Crystals

7 pages, 1400 KiB

Open AccessCommunication

Synthesis of Three-Dimensional Hierarchical Urchinlike Tungsten Trioxide Microspheres for High-Performance Supercapacitor Electrode

by Xu He, Junning Wan, Dong He, Xiaotian Yang, Hui Suo and Chun Zhao

Crystals 2019, 9(9), 485; https://doi.org/10.3390/cryst9090485 - 19 Sep 2019

Cited by 6 | Viewed by 2235

Abstract

In this work, hierarchical three-dimensional (3D) urchinlike WO₃ microspheres with a self-assembled nanorod core, and a connected and quasiconnected nanothorn network shell were synthesized with the hydrothermal method. For the surface or near-surface regions of pseudocapacitive materials that are involved in the [...] Read more.

In this work, hierarchical three-dimensional (3D) urchinlike WO₃ microspheres with a self-assembled nanorod core, and a connected and quasiconnected nanothorn network shell were synthesized with the hydrothermal method. For the surface or near-surface regions of pseudocapacitive materials that are involved in the Faradaic reaction, the urchinlike WO₃ special microstructure provided more effective charge-storage area, exhibiting a high specific capacitance of 488.78 F g⁻¹, low average equivalent-series resistance of 0.966 Ω cm⁻², and excellent cycling stability (84.75% of its initial value after the 10,000 cycles). This performance indicates the urchinlike WO₃ microspheres are promising electrode materials for high-performance supercapacitors. Full article

(This article belongs to the Section Inorganic Crystalline Materials)

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10 pages, 4108 KiB

Open AccessArticle

The Microstructure of Yellow River Ice in the Freezing Period

by Yu Deng, Zongkun Li, Juan Wang and Lukai Xu

Crystals 2019, 9(9), 484; https://doi.org/10.3390/cryst9090484 - 18 Sep 2019

Cited by 5 | Viewed by 2430

Abstract

Accurately determining true ice microstructure and material parameters is a basis for ice disaster theoretical research on the Yellow River. In this work, natural Yellow River ice was collected, and ice crystals parallel and perpendicular to the ice surface were photographed using an [...] Read more.

Accurately determining true ice microstructure and material parameters is a basis for ice disaster theoretical research on the Yellow River. In this work, natural Yellow River ice was collected, and ice crystals parallel and perpendicular to the ice surface were photographed using an orthogonal polarizing mirror. Morphologies of ice microstructure were extracted, and equivalent ice grain sizes were calculated. The results show that Yellow River ice mainly consists of granular ice and columnar ice and vary greatly in different time and space ranges. The ice crystal shape is irregular, and the ice crystal size is larger span, and mainly between 1 mm and 10 mm. Ice crystal initial defects come from bubbles, sediment particles, impurities, and microcracks; among them, bubbles are the most common and have a relatively large impact. In addition, a calculation model of the Yellow River ice microstructure was constructed according to the ice crystal test results. Based on the experimental data and numerical model, the obtained Yellow River ice parameters provide help for analyzing ice disaster mechanisms along the Yellow River. Full article

(This article belongs to the Section Crystalline Materials)

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8 pages, 4419 KiB

Open AccessArticle

The Microalloying Effect of Ce on the Mechanical Properties of Medium Entropy Bulk Metallic Glass Composites

by Yanchun Zhao, Pengbiao Zhao, Wensheng Li, Shengzhong Kou, Jianlong Jiang, Xuejing Mao and Zhuang Yang

Crystals 2019, 9(9), 483; https://doi.org/10.3390/cryst9090483 - 15 Sep 2019

Cited by 8 | Viewed by 2330

Abstract

Novel ultra-strong medium entropy bulk metallic glasses composites (BMGCs) Fe_65.4−xCe_xMn_14.3Si_9.4Cr₁₀C_0.9 and Ti_40−xCe_xNi₄₀Cu₂₀ (x = 0, 1.0), through the martensite transformation induced plasticity (TRIP effect) to [...] Read more.

Novel ultra-strong medium entropy bulk metallic glasses composites (BMGCs) Fe_65.4−xCe_xMn_14.3Si_9.4Cr₁₀C_0.9 and Ti_40−xCe_xNi₄₀Cu₂₀ (x = 0, 1.0), through the martensite transformation induced plasticity (TRIP effect) to enhance both the ductility and work-hardening capability, were fabricated using magnetic levitation melting and copper mold suction via high frequency induction heating. Furthermore, the Ce microalloying effects on microstructure and mechanical behaviors were studied. The Fe-based BMGCs consisted of face-centered cubic (fcc) γ-Fe and body-centered cubic (bcc) α-Fe phase, as well as Ti-based BMGCs containing supercooled B2-Ti (Ni, Cu) and a thermally induced martensite phase B19’-Ti (Ni, Cu). As loading, the TRIP BMGCs exhibited work-hardening behavior, a high fracture strength, and large plasticity, which was attributed to the stress-induced transformation of ε-Fe martensite and B19’-Ti (Ni, Cu) martensite. Ce addition further improved the strengthening and toughening effects of TRIP BMGCs. Adding elemental Ce enhanced the mixing entropy ΔS_mix and atomic size difference δ, while reducing the mixing enthalpy ΔH_mix, thus improving the glass forming ability and delaying the phase transition process, and hence prolonging the work-hardening period before fracturing. The fracture strength σ_f and plastic stress ε_p of Ti₃₉CeNi₄₀Cu₂₀ and Fe_64.4CeMn_14.3Si_9.4Cr₁₀C_0.9 alloys were up to 2635 MPa and 13.8%, and 2905 MPa and 30.1%, respectively. Full article

(This article belongs to the Special Issue Advanced High Temperature Shape Memory Alloys)

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28 pages, 19617 KiB

Open AccessArticle

Aperiodic Photonics of Elliptic Curves

by Luca Dal Negro, Yuyao Chen and Fabrizio Sgrignuoli

Crystals 2019, 9(9), 482; https://doi.org/10.3390/cryst9090482 - 14 Sep 2019

Cited by 8 | Viewed by 3890

Abstract

In this paper we propose a novel approach to aperiodic order in optical science and technology that leverages the intrinsic structural complexity of certain non-polynomial (hard) problems in number theory and cryptography for the engineering of optical media with novel transport and wave [...] Read more.

In this paper we propose a novel approach to aperiodic order in optical science and technology that leverages the intrinsic structural complexity of certain non-polynomial (hard) problems in number theory and cryptography for the engineering of optical media with novel transport and wave localization properties. In particular, we address structure-property relationships in a large number (900) of light scattering systems that physically manifest the distinctive aperiodic order of elliptic curves and the associated discrete logarithm problem over finite fields. Besides defining an extremely rich subject with profound connections to diverse mathematical areas, elliptic curves offer unprecedented opportunities to engineer light scattering phenomena in aperiodic environments beyond the limitations of traditional random media. Our theoretical analysis combines the interdisciplinary methods of point patterns spatial statistics with the rigorous Green’s matrix solution of the multiple wave scattering problem for electric and magnetic dipoles and provides access to the spectral and light scattering properties of novel deterministic aperiodic structures with enhanced light-matter coupling for nanophotonics and metamaterials applications to imaging and spectroscopy. Full article

(This article belongs to the Special Issue Structure and Properties of Quasicrystals)

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13 pages, 3401 KiB

Open AccessArticle

Space Charge Characteristics and Electrical Properties of Micro-Nano ZnO/LDPE Composites

by Jun-Guo Gao, Xia Li, Wen-Hua Yang and Xiao-Hong Zhang

Crystals 2019, 9(9), 481; https://doi.org/10.3390/cryst9090481 - 14 Sep 2019

Cited by 8 | Viewed by 2196

Abstract

The synergistic effects of zinc oxide (ZnO) Micro/Nano particles simultaneously filled in low-density polyethylene (LDPE) on the space charge characteristics and electrical properties has been investigated by melt blending micro-scale and nanoscale ZnO additive particles into LDPE matrix to prepare Micro-ZnO, Nano-ZnO, and [...] Read more.

The synergistic effects of zinc oxide (ZnO) Micro/Nano particles simultaneously filled in low-density polyethylene (LDPE) on the space charge characteristics and electrical properties has been investigated by melt blending micro-scale and nanoscale ZnO additive particles into LDPE matrix to prepare Micro-ZnO, Nano-ZnO, and Micro-Nano ZnO/LDPE composites. The morphological structures of composite samples are characterized by Polarizing Light Microscopy (PLM), and the space charge accumulations and insulation performances are correlated in the analyses with Pulse Electronic Acoustic (PEA), DC breakdown field strength, and conductance tests. It is indicated that both the micro and nano ZnO fillers can introduce plenty of heterogeneous nuclei into the LDPE matrix so as to impede the LDPE spherocrystal growth and regularize the crystalline grains in neatly-arranged morphology. By filling microparticles together with nanoparticles of ZnO additives, the space charge accumulations are significantly inhibited under an applied DC voltage and the minimum initial residual charges with the slowest charge decaying rate have been achieved after an electrode short connection. While the micro-nano ZnO/LDPE composites acquire the lowest conductivity, the breakdown strengths of the ZnO/LDPE nanocomposite and micro-nano composite are, respectively, 13.7% and 3.4% higher than that of the neat LDPE material. Full article

(This article belongs to the Section Inorganic Crystalline Materials)

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17 pages, 1366 KiB

Open AccessEditor’s ChoiceArticle

Critical Review of Scintillating Crystals for Neutron Detection

by Michał J. Cieślak, Kelum A. A. Gamage and Robert Glover

Crystals 2019, 9(9), 480; https://doi.org/10.3390/cryst9090480 - 13 Sep 2019

Cited by 56 | Viewed by 9218

Abstract

There exists an ongoing need to develop and improve methods of detecting radioactive materials. As each radioactive isotope leaves a unique mark in a form of the particles it emits, new materials capable of detecting and measuring these particles are constantly sought. Neutrons [...] Read more.

There exists an ongoing need to develop and improve methods of detecting radioactive materials. As each radioactive isotope leaves a unique mark in a form of the particles it emits, new materials capable of detecting and measuring these particles are constantly sought. Neutrons and their detectors play a significant role in areas such as nuclear power generation, nuclear decommissioning and decontamination, border security, nuclear proliferation and nuclear medicine. Owing to the complexity of their detection, as well as scarcity of ³He, which has historically been the preferred choice for neutron detection in many application fields, new sensitive materials are sought. Organic and inorganic scintillating crystals have been recognised as particularly good alternatives, and as such systems that utilise them are increasingly common. As they allow investigation of the neutron energy spectra, greater information about the radioactive source can be inferred. Therefore, in this article, an extensive review of scintillating crystals used for neutron detection is presented. By describing the history of scintillating crystals and discussing changes that occurred in their use and development of methods for radiation detection, the authors present a comprehensive overview of the current situation. Supported by a practical example, possible future directions of the research area are also presented. Full article

(This article belongs to the Special Issue Scintillator Crystals: Structure, Characterization and Models for Better Performances)

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13 pages, 2836 KiB

Open AccessArticle

Application of GISAXS in the Investigation of Three-Dimensional Lattices of Nanostructures

by Lovro Basioli, Krešimir Salamon, Marija Tkalčević, Igor Mekterović, Sigrid Bernstorff and Maja Mičetić

Crystals 2019, 9(9), 479; https://doi.org/10.3390/cryst9090479 - 13 Sep 2019

Cited by 14 | Viewed by 3602

Abstract

The application of the grazing-incidence small-angle X-ray scattering (GISAXS) technique for the investigation of three-dimensional lattices of nanostructures is demonstrated. A successful analysis of three-dimensionally ordered nanostructures requires applying a suitable model for the description of the nanostructure ordering. Otherwise, it is possible [...] Read more.

The application of the grazing-incidence small-angle X-ray scattering (GISAXS) technique for the investigation of three-dimensional lattices of nanostructures is demonstrated. A successful analysis of three-dimensionally ordered nanostructures requires applying a suitable model for the description of the nanostructure ordering. Otherwise, it is possible to get a good agreement between the experimental and the simulated data, but the parameters obtained by fitting may be completely incorrect. In this paper, we theoretically examine systems having different types of nanostructure ordering, and we show how the choice of the correct model for the description of ordering influences the analysis results. Several theoretical models are compared in order to show how to use GISAXS in the investigation of self-assembled arrays of nanoparticles, and also in arrays of nanostructures obtained by ion-beam treatment of thin films or surfaces. All models are supported by experimental data, and the possibilities and limitations of GISAXS for the determination of material structure are discussed. Full article

(This article belongs to the Special Issue Investigation of Nanostructures with X-ray Scattering Techniques)

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40 pages, 4947 KiB

Open AccessReview

Intermolecular Interactions in Functional Crystalline Materials: From Data to Knowledge

by Anna V. Vologzhanina

Crystals 2019, 9(9), 478; https://doi.org/10.3390/cryst9090478 - 13 Sep 2019

Cited by 42 | Viewed by 7889

Abstract

Intermolecular interactions of organic, inorganic, and organometallic compounds are the key to many composition–structure and structure–property networks. In this review, some of these relations and the tools developed by the Cambridge Crystallographic Data Center (CCDC) to analyze them and design solid forms with [...] Read more.

Intermolecular interactions of organic, inorganic, and organometallic compounds are the key to many composition–structure and structure–property networks. In this review, some of these relations and the tools developed by the Cambridge Crystallographic Data Center (CCDC) to analyze them and design solid forms with desired properties are described. The potential of studies supported by the Cambridge Structural Database (CSD)-Materials tools for investigation of dynamic processes in crystals, for analysis of biologically active, high energy, optical, (electro)conductive, and other functional crystalline materials, and for the prediction of novel solid forms (polymorphs, co-crystals, solvates) are discussed. Besides, some unusual applications, the potential for further development and limitations of the CCDC software are reported. Full article

(This article belongs to the Special Issue Chemical Bonding in Crystals and Their Properties)

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Graphical abstract

9 pages, 3124 KiB

Open AccessArticle

Two Tetranuclear Butterfly-Shaped Co(II) Complexes: Structure, Mass Spectrometric, and Magnetism

by Qian-Jun Deng, Min Chen, Dong-Chu Chen and Chang-Ai Chen

Crystals 2019, 9(9), 477; https://doi.org/10.3390/cryst9090477 - 13 Sep 2019

Viewed by 1997

Abstract

The organic ligand (1-methyl-1H-benzo[d]imidazol-2-yl)methanol (HL) was used to react with CoX₂·6H₂O (X = Cl and Br) under solvothermal conditions to obtain the complex [Co₄(L)₆(X)₂] (1, X = Cl; 2, [...] Read more.

The organic ligand (1-methyl-1H-benzo[d]imidazol-2-yl)methanol (HL) was used to react with CoX₂·6H₂O (X = Cl and Br) under solvothermal conditions to obtain the complex [Co₄(L)₆(X)₂] (1, X = Cl; 2, X = Br). The butterfly-shaped structure of complex 1 and 2 suggest that Co(II) ions have two different coordinated modes, which are five coordination with O₃NX environment and six coordination with O₄N₂ environment. In addition, the electrospray ionization mass spectrometry (ESI-MS) analysis indicated that the ion molecular fragment of highest intensity was [Co₄(L)₆]²⁺, and there existed a high nuclear fragment peak of [Co₇(L)₁₂]²⁺. Interestingly, it was basically completely transformed into [Co₇(L)₁₂]²⁺ two days later, so those two complexes were relatively stable in CH₃OH. Magnetic characterization exhibited that complex 1 and 2 display field-induced single-molecule magnetic behavior, of which the energy hills U_eff/k_B were 28 and 20 K under direct-current field of 0.1 T, respectively. Full article

(This article belongs to the Section Crystal Engineering)

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19 pages, 7084 KiB

Open AccessArticle

Nanodefects in YAG:Ce-Based Phosphor Microcrystals

by Victor Lisitsyn, Ludmila Lisitsyna, Aida Tulegenova, Yangyang Ju, Elena Polisadova, Evgeniy Lipatov and Vitaliy Vaganov

Crystals 2019, 9(9), 476; https://doi.org/10.3390/cryst9090476 - 11 Sep 2019

Cited by 22 | Viewed by 3706

Abstract

The present paper focused on the study of spectral–kinetic characteristics of luminescence in two batches of yttrium aluminum garnet (YAG):Ce-based phosphors synthesized in different years by two manufacturers: NPO “Platan” in Russia and “GrandLux” in the People’s Republic of China (PRC). Upon studying [...] Read more.

The present paper focused on the study of spectral–kinetic characteristics of luminescence in two batches of yttrium aluminum garnet (YAG):Ce-based phosphors synthesized in different years by two manufacturers: NPO “Platan” in Russia and “GrandLux” in the People’s Republic of China (PRC). Upon studying the structural characteristics of the phosphors—elemental composition, morphology, and X-ray diffraction (XRD) patterns—it was concluded that both types of YAG:Ce phosphors are highly imperfect. The presence of heterogeneities of different nature was accompanied by the introduction—to compensate for charges and elastic stresses—of intrinsic lattice defects during synthesis. There is a high probability of creating complex defects during phosphor synthesis. Luminescence properties (full width at half maximum (FWHM), spectral position of the emission peaks, excitation spectra of emission, emission decay time) are affected by the nearest environment of the luminescence center; whereas the degree of correlation of defects (distance between the components of the donor–acceptor pair) does not depend on the concentration of impurities, intrinsic defects, and their ratio. The results do not fit into the framework of existing ideas regarding the processes in phosphors as systems with widely distributed luminescence centers. The patterns obtained in the paper are discussed based on a hypothesis according to which a nanodefect phosphorus crystal phase is formed during the synthesis. Full article

(This article belongs to the Special Issue Non-Classical Crystal Growth)

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16 pages, 2566 KiB

Open AccessFeature PaperReview

Impact of Dispersion of Nanoscale Particles on the Properties of Nematic Liquid Crystals

by Shri Singh

Crystals 2019, 9(9), 475; https://doi.org/10.3390/cryst9090475 - 11 Sep 2019

Cited by 24 | Viewed by 3904

Abstract

This work reviews the recent progress made in last decade in understanding the role of dispersion of nanoparticles and quantum dots into host nematic liquid crystals. There are two important ingredients of this work: Even a minute concentration of these non-mesogenic materials in [...] Read more.

This work reviews the recent progress made in last decade in understanding the role of dispersion of nanoparticles and quantum dots into host nematic liquid crystals. There are two important ingredients of this work: Even a minute concentration of these non-mesogenic materials in host matrix can have reflective impact on the dielectric, electro-optical, and spectroscopic properties of host nematics and the nematic-nanoparticles composite systems become suitable for the use in nematic based display and other devices. Full article

(This article belongs to the Special Issue Liquid Crystal Nanocomposites and Their Photonics Applications)

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9 pages, 2544 KiB

Open AccessArticle

CuZnSn(S_xSe_1-x)₄ Solar Cell Prepared by the Sol-Gel Method Following a Modified Three-Step Selenization Process

by Xunan Shen, Chengchun Tang, Chao Zhang, Guanda Li, Yue Zhao, Wei Li, Guifeng Chen and Tie Yang

Crystals 2019, 9(9), 474; https://doi.org/10.3390/cryst9090474 - 11 Sep 2019

Cited by 3 | Viewed by 2703

Abstract

In current work, Cu₂ZnSn(S,Se)₄ thin films have been prepared by the sol-gel method based on dimethyl sulfoxide solution followed by a modified three-step selenization process. The key process of this method is to divide the Se evaporation and annealing into [...] Read more.

In current work, Cu₂ZnSn(S,Se)₄ thin films have been prepared by the sol-gel method based on dimethyl sulfoxide solution followed by a modified three-step selenization process. The key process of this method is to divide the Se evaporation and annealing into two different stages: employ a thermal cracking Se source in the Se evaporation stage and an above-atmospheric pressure in the annealing process. The morphological, structural, elemental distributional, and photovoltaic properties of Cu₂ZnSn(S,Se)₄ thin films prepared with the three-step selenization process were systematically investigated. It was found that through this modified selenization process, the formations of secondary phases (ZnSe, CuSnSe₃) and a fine-grain bottom layer, which usually exists in the traditional one-step selenization process, were effectively suppressed. These improvements could further reduce the carrier recombination and improve the solar cell performance. The best solar cell is obtained with a short-circuit current density of 28.16 mA/cm², open-circuit voltage of 404.91 mV, fill factor of 62.91%, and a power conversion efficiency of 7.17% under air mass 1.5 (100 mW/cm²) illumination. Full article

(This article belongs to the Special Issue Advances in Thin Film Solar Cells)

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13 pages, 2567 KiB

Open AccessArticle

Dielectric Properties of Chiral Ferroelectric Liquid Crystalline Compounds with Three Aromatic Rings Connected by Ester Groups

by Malay Kumar Das, Barnali Barman, Banani Das, Věra Hamplová and Alexey Bubnov

Crystals 2019, 9(9), 473; https://doi.org/10.3390/cryst9090473 - 10 Sep 2019

Cited by 9 | Viewed by 3212

Abstract

The tilted ferroelectric SmC* phase of three structurally different series having three aromatic rings in the core structure connected by ester groups with different end alkyl chain lengths, all of which are derived from lactic acid, have been observed by broadband dielectric spectroscopy. [...] Read more.

The tilted ferroelectric SmC* phase of three structurally different series having three aromatic rings in the core structure connected by ester groups with different end alkyl chain lengths, all of which are derived from lactic acid, have been observed by broadband dielectric spectroscopy. Introduction of structural variations within the liquid crystalline compounds has led to the formation of chiral nematic N*, or the paraelectric orthogonal SmA* phase at higher temperatures. The dielectric spectra strongly depend both on the temperature as well as the specific molecular structure of the self-assembling compounds possessing the ferroelectric polar order. The results reveal a strong Goldstone mode in the ferroelectric SmC* phase with ~kHz relaxation frequency. In the SmC* phase, the real and imaginary parts of the complex permittivity increase up to certain temperature near the SmC*-N*/SmA* transition and then decrease with increasing temperature, perhaps due to the disruption of the molecular domains at the onset of the SmA*/N* phase transition. The dielectric strength attains a maximum value in the SmC* phase and then decreases near the SmA*/N* phase transition. The dielectric strength is also influenced by the lengths of the alkyl chain and the nature of the connecting unit of the constituent molecules. The relaxation time and the relaxation frequency are found to vary with the molecular structure of the studied ferroelectric compounds. Full article

(This article belongs to the Special Issue Ferroelectric and Ferromagnetic Liquid Crystals)

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Graphical abstract

13 pages, 3419 KiB

Open AccessArticle

Comparison of Candida Albicans Fatty Acid Amide Hydrolase Structure with Homologous Amidase Signature Family Enzymes

by Cho-Ah Min, Ji-Sook Yun, Eun Hwa Choi, Ui Wook Hwang, Dong-Hyung Cho, Je-Hyun Yoon and Jeong Ho Chang

Crystals 2019, 9(9), 472; https://doi.org/10.3390/cryst9090472 - 10 Sep 2019

Cited by 3 | Viewed by 3067

Abstract

Fatty acid amide hydrolase (FAAH) is a well-characterized member of the amidase signature (AS) family of serine hydrolases. The membrane-bound FAAH protein is responsible for the catabolism of neuromodulatory fatty acid amides, including anandamide and oleamide, that regulate a wide range of mammalian [...] Read more.

Fatty acid amide hydrolase (FAAH) is a well-characterized member of the amidase signature (AS) family of serine hydrolases. The membrane-bound FAAH protein is responsible for the catabolism of neuromodulatory fatty acid amides, including anandamide and oleamide, that regulate a wide range of mammalian behaviors, including pain perception, inflammation, sleep, and cognitive/emotional state. To date, limited crystal structures of FAAH and non-mammalian AS family proteins have been determined and used for structure-based inhibitor design. In order to provide broader structural information, the crystal structure of FAAH from the pathogenic fungus Candida albicans was determined at a resolution of 2.2 Å. A structural comparison with a brown rat Rattus norvegicus FAAH as well as with other bacterial AS family members, MAE2 and PAM, showed overall similarities but there were several discriminative regions found: the transmembrane domain and the hydrophobic cap of the brown rat FAAH were completely absent in the fungal FAAH structure. Along with these results, a phylogenetic analysis of 19 species within the AS family showed that fungal FAAHs diverged from a common ancestor before the separation of eukarya and prokarya. Taken together, this study provides insights into developing more potent inhibitors of FAAH as well as expanding our knowledge of the relationships between AS family members. Full article

(This article belongs to the Special Issue Crystallographic Studies of Enzymes)

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13 pages, 2237 KiB

Open AccessArticle

Crystal Structure of NADPH-Dependent Methylglyoxal Reductase Gre2 from Candida Albicans

by Giang Thu Nguyen, Shinae Kim, Hyeonseok Jin, Dong-Hyung Cho, Hang-Suk Chun, Woo-Keun Kim and Jeong Ho Chang

Crystals 2019, 9(9), 471; https://doi.org/10.3390/cryst9090471 - 10 Sep 2019

Cited by 3 | Viewed by 3385

Abstract

Gre2 is a key enzyme in the methylglyoxal detoxification pathway; it uses NADPH or NADH as an electron donor to reduce the cytotoxic methylglyoxal to lactaldehyde. This enzyme is a member of the short-chain dehydrogenase/reductase (SDR) superfamily whose members catalyze this type of [...] Read more.

Gre2 is a key enzyme in the methylglyoxal detoxification pathway; it uses NADPH or NADH as an electron donor to reduce the cytotoxic methylglyoxal to lactaldehyde. This enzyme is a member of the short-chain dehydrogenase/reductase (SDR) superfamily whose members catalyze this type of reaction with a broad range of substrates. To elucidate the structural features, we determined the crystal structures of the NADPH-dependent methylglyoxal reductase Gre2 from Candida albicans (CaGre2) for both the apo-form and NADPH-complexed form at resolutions of 2.8 and 3.02 Å, respectively. The CaGre2 structure is composed of two distinct domains: the N-terminal cofactor-binding domain and the C-terminal substrate-binding domain. Extensive comparison of CaGre2 with its homologous structures reveals conformational changes in α12 and β3′ of the NADPH-complex forms. This study may provide insights into the structural and functional variation of SDR family proteins. Full article

(This article belongs to the Special Issue Crystallographic Studies of Enzymes)

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21 pages, 10074 KiB

Open AccessReview

Ferroelectric Liquid Crystals: Physics and Applications

by Qi Guo, Kexin Yan, Vladimir Chigrinov, Huijie Zhao and Michael Tribelsky

Crystals 2019, 9(9), 470; https://doi.org/10.3390/cryst9090470 - 09 Sep 2019

Cited by 54 | Viewed by 9930

Abstract

Electrooptic modes with fast response and high contrast ratio are highly desirable in modern photonics and displays. Ferroelectric liquid crystals (FLCs) are especially promising for fulfilling these demands by employing photoalignment technology in FLC cells. Three electrooptic modes including surface stabilized FLC (SSFLC), [...] Read more.

Electrooptic modes with fast response and high contrast ratio are highly desirable in modern photonics and displays. Ferroelectric liquid crystals (FLCs) are especially promising for fulfilling these demands by employing photoalignment technology in FLC cells. Three electrooptic modes including surface stabilized FLC (SSFLC), deformed helix ferroelectric (DHF) mode, and electrically suppressed helix (ESH) mode are reviewed with the corresponding electrooptic effects like bi- and multi-stable switching, continuous modulation of grayscale or phase, and high contrast switching. The general operation principles FLC electrooptic modes are described, and then the characteristics of each modes for potential applications are summarized. With the advantages of controllable anchoring energy, the photoalignment provides FLC samples with uniform alignment and high contrast ratio. The fast FLCs with a high resolution and high contrast can be used in the next generation display including field sequential color FLC microdisplays, as well as switchable 2D/3D televisions. Full article

(This article belongs to the Special Issue Liquid Crystal Optics and Physics: Recent Advances and Prospects)

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13 pages, 2312 KiB

Open AccessArticle

The Field-Induced Stop-Bands and Lasing Modes in CLC Layers with Deformed Lying Helix

by Serguei P. Palto

Crystals 2019, 9(9), 469; https://doi.org/10.3390/cryst9090469 - 08 Sep 2019

Cited by 7 | Viewed by 2256

Abstract

Waveguide optical properties of a cholesteric liquid crystal (CLC) layer with a deformed lying helix (DLH) have been studied by numerical simulations using the finite difference time domain method. The DLH structure, when the helix’s axis is oriented in plane of a CLC [...] Read more.

Waveguide optical properties of a cholesteric liquid crystal (CLC) layer with a deformed lying helix (DLH) have been studied by numerical simulations using the finite difference time domain method. The DLH structure, when the helix’s axis is oriented in plane of a CLC layer, is induced by an electric field in a virtual CLC cell with periodic (planar/homeotropic) boundary conditions at one of the alignment surfaces. This in-plane helical structure is stable only in a permanently applied electric field providing the helix deformation. In this work the polarized light reflectance spectra have been studied at different electric fields and light impingement into a waveguide formed by the DLH layer. It is found that for light propagating along the helix axis the reflectance spectrum has multiple stop-bands centred at wavelengths

λ_{j} = \frac{2 p ⟨ n ⟩}{j}

, which is different from set of bands located at

λ_{j} = \frac{p ⟨ n ⟩}{j}

, and characteristic of CLC spectra for the Grandjean-plane textures subjected to distortion by an electric or magnetic field perpendicular to the helix axis, where j is a natural number, p is the helix pitch and

⟨ n ⟩

is the average refractive index. Each of the higher order (j > 1) bands consists of three polarization-dependent sub-bands. In the case of an amplifying CLC DLH layer, depending on an extent of the helix deformation, the lasing modes can be excited at different edges of the sub-bands. While at the strongest deformation the lasing is preferable at the edges of the central sub-band; a lower extent of deformation makes favourable conditions for the lasing at edges of the two other sub-bands. Full article

(This article belongs to the Special Issue Localized Optical Modes in Liquid Crystals)

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9 pages, 4680 KiB

Open AccessArticle

High Magnetic Field ESR in S = 1 Skew Chain Antiferromagnet Ni₂V₂O₇ Single Crystal

by Lei Yin, Zhongwen Ouyang, Xiaoyu Yue, Zhenxing Wang and Zhengcai Xia

Crystals 2019, 9(9), 468; https://doi.org/10.3390/cryst9090468 - 07 Sep 2019

Cited by 2 | Viewed by 3135

Abstract

We report electron spin resonance (ESR) in S = 1 skew chain antiferromagnet Ni₂V₂O₇, which exhibits a spin-flop transition and a well-defined 1/2 magnetization plateau. The antiferromagnetic (AFM) ordering at T_N = 7 K can be [...] Read more.

We report electron spin resonance (ESR) in S = 1 skew chain antiferromagnet Ni₂V₂O₇, which exhibits a spin-flop transition and a well-defined 1/2 magnetization plateau. The antiferromagnetic (AFM) ordering at T_N = 7 K can be reflected by the temperature-dependent ESR spectra at low frequency for the easy axis. At 2 K, at the spin-flop transition fields along the easy a and b axes, anomalies are observed from the frequency‒field relationship. However, these modes cannot be understood by the conventional two-sublattice AFM resonance theory with uniaxial anisotropy. For the easy b axis, an unusual resonance mode is observed and its resonance field increases with decreasing frequency. This ESR mode becomes softening at ~8 T, corresponding to the onset of the 1/2 magnetization plateau. Full article

(This article belongs to the Special Issue Magnetic Field-induced Phase Transition)

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16 pages, 13663 KiB

Open AccessArticle

Site Selectivity of Halogen Oxygen Bonding in 5- and 6-Haloderivatives of Uracil

by Gustavo Portalone

Crystals 2019, 9(9), 467; https://doi.org/10.3390/cryst9090467 - 06 Sep 2019

Cited by 5 | Viewed by 2645

Abstract

Seven 5-and 6-halogenated derivatives of uracil or 1-methyluracil (halogen = Cl, Br, I) were studied by single crystal X-ray diffraction. In contrast with pure 5-halouracils, where the presence of N-H⋯O and C-H⋯O hydrogen bonds prevents the formation of other intermolecular interactions, the general [...] Read more.

Seven 5-and 6-halogenated derivatives of uracil or 1-methyluracil (halogen = Cl, Br, I) were studied by single crystal X-ray diffraction. In contrast with pure 5-halouracils, where the presence of N-H⋯O and C-H⋯O hydrogen bonds prevents the formation of other intermolecular interactions, the general ability of pyrimidine nucleobases to provide electron donating groups to halogen bonding was confirmed in three crystals and cocrystals containing uracil with the halogen atom at the C6 position. In the latter compounds, among the two nucleophilic oxygen atoms in the C=O moiety, only the urea carbonyl oxygen O1 can act as halogen bond acceptor, being not saturated by conventional hydrogen bonds. The halogen bonds in pure 6-halouracils are all rather weak, as supported by Hirshfeld surface analysis. The strongest interaction was found in the structure of 6-iodouracil, which displayed the largest (13%) reduction of the sum of van der Waals (vdW) radii for the contact atoms. Despite this, halogen bonding plays a role in determining the crystal packing of 6-halouracils, acting alongside conventional hydrogen bonds. Full article

(This article belongs to the Special Issue Characterisation and Study of Compounds by Single Crystal X-Ray Diffraction)

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10 pages, 2667 KiB

Open AccessArticle

Synthesis and Characterization of a New Aluminum-Doped Bismuth Subcarbonate

by Loisangela Álvarez, Blanca Rojas de Gascue, Rolando J. Tremont, Edgar Márquez and Euclides J. Velazco

Crystals 2019, 9(9), 466; https://doi.org/10.3390/cryst9090466 - 06 Sep 2019

Cited by 3 | Viewed by 2526

Abstract

A new compound, Bi₂O₂CO₃:Al, was synthesized by the coprecipitation method. The characterization was done by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), electronic scanning microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). [...] Read more.

A new compound, Bi₂O₂CO₃:Al, was synthesized by the coprecipitation method. The characterization was done by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), electronic scanning microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). The characterization methods allowed to identify the Bi₂O₂CO₃:Al compound, such as the Al-doped Bi₂O₂CO₃ by XRD, the anionic part (CO₃²⁻) by FTIR, and the presence of aluminum in the compound by XPS and EDX. It was confirmed to have a nanostructure like a nanosheet and a microstructure that resembles a type sponge by SEM. Full article

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10 pages, 2896 KiB

Open AccessArticle

Sensing Characteristics of Side-Polished Fiber Based on the Alterations in Helical Structure of Thermo-Sensitive Cholesteric Liquid Crystals

by Yuqi Han, Yan Jiang and Wei Guo

Crystals 2019, 9(9), 465; https://doi.org/10.3390/cryst9090465 - 05 Sep 2019

Cited by 4 | Viewed by 2553

Abstract

Cholesteric liquid crystals (CLCs) are sensitive to environmental temperature changes, and have been employed as a specific intermediary for biosensors. Considering the temperature-dependent structural changes of CLCs, this study aimed to determine the sensing properties of side-polished fibers (SPFs) after coating with CLCs. [...] Read more.

Cholesteric liquid crystals (CLCs) are sensitive to environmental temperature changes, and have been employed as a specific intermediary for biosensors. Considering the temperature-dependent structural changes of CLCs, this study aimed to determine the sensing properties of side-polished fibers (SPFs) after coating with CLCs. The experimental results demonstrated that, with regard to the transmitted spectrum, the loss peak of CLC-coated SPFs exhibited a positive linear relationship with temperature changes over a range of 20 to 50 °C. The linear correlation coefficient achieved 97.8% when the temperature increased by 10 °C, and the loss peak drifted by 12.72 nm. The reflectance spectrum of CLCs coated on the polished surface were obtained using optical fiber sensors. The feasibility of measuring the helical structure of CLCs was further verified using SPF transmission spectroscopy. The findings indicated that the transmitted spectrum of SPFs could be adopted to characterize the helical structure of CLCs, which lays a solid foundation for further study on SPF-based biosensors. Full article

(This article belongs to the Special Issue Advances in Cholesteric Liquid Crystals)

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11 pages, 1515 KiB

Open AccessArticle

Synthesis, Characterization, and Crystal Structure Determination of a New Lithium Zinc Iodate Polymorph LiZn(IO₃)₃

by Zoulikha Hebboul, Christine Galez, Djamal Benbertal, Sandrine Beauquis, Yannick Mugnier, Abdelnour Benmakhlouf, Mohamed Bouchenafa and Daniel Errandonea

Crystals 2019, 9(9), 464; https://doi.org/10.3390/cryst9090464 - 04 Sep 2019

Cited by 12 | Viewed by 3855

Abstract

Synthesis and characterization of anhydrous LiZn(IO₃)₃ powders prepared from an aqueous solution are reported. Morphological and compositional analyses were carried out by using scanning electron microscopy and energy-dispersive X-ray measurements. The synthesized powders exhibited a needle-like morphology after annealing at [...] Read more.

Synthesis and characterization of anhydrous LiZn(IO₃)₃ powders prepared from an aqueous solution are reported. Morphological and compositional analyses were carried out by using scanning electron microscopy and energy-dispersive X-ray measurements. The synthesized powders exhibited a needle-like morphology after annealing at 400 °C. A crystal structure for the synthesized compound was proposed from powder X-ray diffraction and density-functional theory calculations. Rietveld refinements led to a monoclinic structure, which can be described with space group P2₁, number 4, and unit-cell parameters a = 21.874(9) Å, b = 5.171(2) Å, c = 5.433(2) Å, and β = 120.93(4)°. Density-functional theory calculations supported the same crystal structure. Infrared spectra were also collected, and the vibrations associated with the different modes were discussed. The non-centrosymmetric space group determined for this new polymorph of LiZn(IO₃)₃, the characteristics of its infrared absorption spectrum, and the observed second-harmonic generation suggest it is a promising infrared non-linear optical material. Full article

(This article belongs to the Special Issue Polymorphism in Crystal)

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3 pages, 177 KiB

Open AccessEditorial

First-Principles Prediction of Structures and Properties in Crystals

by Andreas Hermann and Dominik Kurzydłowski

Crystals 2019, 9(9), 463; https://doi.org/10.3390/cryst9090463 - 04 Sep 2019

Cited by 2 | Viewed by 2370

Abstract

The term “first-principles calculations” is a synonym for the numerical determination of the electronic structure of atoms, molecules, clusters, or materials from ‘first principles’, i [...] Full article

(This article belongs to the Special Issue First-Principles Prediction of Structures and Properties in Crystals)

8 pages, 1147 KiB

Open AccessFeature PaperArticle

Analysis of Glulisine Crystallisation Utilising Phase Diagrams and Nucleants

by Yanmin Li, Lata Govada, Hodaya V. Solomon, Richard B. Gillis, Gary G. Adams and Naomi E. Chayen

Crystals 2019, 9(9), 462; https://doi.org/10.3390/cryst9090462 - 03 Sep 2019

Cited by 3 | Viewed by 3357

Abstract

Glulisine is a US Food and Drug Administration (FDA) approved insulin analogue, used for controlling hyperglycaemia in patients with diabetes mellitus (DM). It is fast acting which better approximates physiological insulin secretion, improving patient outcome. Crystallisation of Glulisine was analysed by its crystallisation [...] Read more.

Glulisine is a US Food and Drug Administration (FDA) approved insulin analogue, used for controlling hyperglycaemia in patients with diabetes mellitus (DM). It is fast acting which better approximates physiological insulin secretion, improving patient outcome. Crystallisation of Glulisine was analysed by its crystallisation phase diagram and nucleation-inducing materials. Both the hanging drop vapour diffusion and microbatch-under-oil methods were used and compared. We have shown that the same protein can have different solubility behaviours depending on the nature of the salt in the precipitating agent. In the case of Glulisine with magnesium formate, lowering the precipitant concentration drove the system further into supersaturation resulting in the formation of crystals and precipitation. This was the opposite effect to the usual scenario where raising the precipitant concentration leads to supersaturation. Glulisine with sodium potassium tartrate tetrahydrate (NaKT) followed the expected trend of forming crystals or precipitate at higher concentrations and clear drops at lower concentrations of the precipitant. The outcomes of crystallisation using the different crystallisation methods is also described. Glulisine was successfully crystallised and the crystals diffracted up to a resolution limit of 1.4 Å. Full article

(This article belongs to the Special Issue Advanced Methods to Monitor and Control the Crystallisation Environment)

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10 pages, 3281 KiB

Open AccessArticle

All-Optical Ultra-Fast Graphene-Photonic Crystal Switch

by Mohammad Reza Jalali Azizpour, Mohammad Soroosh, Narges Dalvand and Yousef Seifi-Kavian

Crystals 2019, 9(9), 461; https://doi.org/10.3390/cryst9090461 - 03 Sep 2019

Cited by 34 | Viewed by 4265

Abstract

In this paper, an all-optical photonic crystal-based switch containing a graphene resonant ring has been presented. The structure has been composed of 15 × 15 silicon rods for a fundamental lattice. Then, a resonant ring including 9 thick silicon rods and 24 graphene-SiO [...] Read more.

In this paper, an all-optical photonic crystal-based switch containing a graphene resonant ring has been presented. The structure has been composed of 15 × 15 silicon rods for a fundamental lattice. Then, a resonant ring including 9 thick silicon rods and 24 graphene-SiO₂ rods was placed between two waveguides. The thick rods with a radius of 0.41a in the form of a 3 × 3 lattice were placed at the center of the ring. Graphene-SiO₂ rods with a radius of 0.2a were assumed around the thick rods. These rods were made of the graphene monolayers which were separated by SiO₂ disks. The size of the structure was about 70 µm² that was more compact than other works. Furthermore, the rise and fall times were obtained by 0.3 ps and 0.4 ps, respectively, which were less than other reports. Besides, the amount of the contrast ratio (the difference between the margin values for logics 1 and 0) for the proposed structure was calculated by about 82%. The correct switching operation, compactness, and ultra-fast response, as well as the high contrast ratio, make the presented switch for optical integrated circuits. Full article

(This article belongs to the Special Issue Sonic and Photonic Crystals)

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8 pages, 1223 KiB

Open AccessArticle

Low-Temperature Polymorphic Transformation of β-Lactam Antibiotics

by Hongyuan Luo, Jinyun Liu, Xiao He and Jinjin Li

Crystals 2019, 9(9), 460; https://doi.org/10.3390/cryst9090460 - 02 Sep 2019

Cited by 4 | Viewed by 2878

Abstract

Abstract: Polymorphic screening and transformation of molecular crystals are presently popular research areas in pharmaceutical studies. In this study, we developed an ab initio method to examine the structures, spectra, and stabilities of β-lactam (trans-13-azabicyclo[10.2.0]tetradecan-14-one), an important component of antibiotics. Based on [...] Read more.

Abstract: Polymorphic screening and transformation of molecular crystals are presently popular research areas in pharmaceutical studies. In this study, we developed an ab initio method to examine the structures, spectra, and stabilities of β-lactam (trans-13-azabicyclo[10.2.0]tetradecan-14-one), an important component of antibiotics. Based on the density functional theory (DFT) and second-order Møller-Plesset perturbation (MP2) methods, the present work demonstrated that forms I and II have isomorphic structures but can be distinguished by their Gibbs free energies and vibrational spectra. Forms I and II show a low-temperature polymorphic transformation at 308 K, where form I is stable below 308 K and form II is stable above 308 K. The proposed method suggests that the theoretical calculation can be used as a tool to effectively distinguish the isomorphic structures, and temperature-induced polymorphic transformation has far-reaching significance for drug storage and design. Full article

(This article belongs to the Special Issue Crystallography of Structural Phase Transformations)

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11 pages, 3995 KiB

Open AccessArticle

An Integrated Photonic Electric-Field Sensor Utilizing a 1 × 2 YBB Mach-Zehnder Interferometric Modulator with a Titanium-Diffused Lithium Niobate Waveguide and a Dipole Patch Antenna

by Hongsik Jung

Crystals 2019, 9(9), 459; https://doi.org/10.3390/cryst9090459 - 02 Sep 2019

Cited by 14 | Viewed by 3885

Abstract

We studied photonic electric-field sensors using a 1 × 2 YBB-MZI modulator composed of two complementary outputs and a 3 dB directional coupler based on the electro-optic effect and titanium diffused lithium–niobate optical waveguides. The measured DC switching voltage and extinction ratio at [...] Read more.

We studied photonic electric-field sensors using a 1 × 2 YBB-MZI modulator composed of two complementary outputs and a 3 dB directional coupler based on the electro-optic effect and titanium diffused lithium–niobate optical waveguides. The measured DC switching voltage and extinction ratio at the wavelength 1.3 μm were ~16.6 V and ~14.7 dB, respectively. The minimum detectable fields were ~1.12 V/m and ~3.3 V/m, corresponding to the ~22 dB and ~18 dB dynamic ranges of ~10 MHz and 50 MHz, respectively, for an rf power of 20 dBm. The sensor shows an almost linear response to the applied electric-field strength within the range of 0.29 V/m to 29.8 V/m. Full article

(This article belongs to the Special Issue Recent Progress in Lithium Niobate)

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29 pages, 3902 KiB

Open AccessArticle

Autowave Physics of Material Plasticity

by Lev B. Zuev and Svetlana A. Barannikova

Crystals 2019, 9(9), 458; https://doi.org/10.3390/cryst9090458 - 02 Sep 2019

Cited by 35 | Viewed by 2965

Abstract

The notions of plastic flow localization are outlined in the paper. It is shown that each type of localized plasticity pattern corresponds to a definite stage of deformation hardening. In the course of plastic flow development, a changeover in the types of localization [...] Read more.

The notions of plastic flow localization are outlined in the paper. It is shown that each type of localized plasticity pattern corresponds to a definite stage of deformation hardening. In the course of plastic flow development, a changeover in the types of localization patterns occurs. The types of localization patterns are limited in number: four pattern types are all that can be expected. A correspondence was set up between the emergent localization pattern and the respective flow stage. It is found that the localization patterns are manifestations of the autowave nature of plastic flow localization process, with each pattern type corresponding to a definite mode of autowave. In the course of plastic flow development, the following modes of autowaves will form in the following sequence: switching autowave → phase autowave → stationary dissipative structure → collapse of the autowave. Of particular interest are the phase autowave and the respective pattern observed. Propagation velocity, dispersion, and grain size dependence of wavelength were determined experimentally for the phase autowave. An elastic-plastic strain invariant was also introduced to relate the elastic and plastic properties of the deforming medium. It is found that the autowave characteristics follow directly from this invariant. Full article

(This article belongs to the Special Issue Elasticity and Micro- and Macro- Plasticity of Crystals)

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11 pages, 1926 KiB

Open AccessArticle

Bubbly Water as a Natural Metamaterial of Negative Bulk-Modulus

by Pi-Gang Luan

Crystals 2019, 9(9), 457; https://doi.org/10.3390/cryst9090457 - 01 Sep 2019

Cited by 4 | Viewed by 4514

Abstract

In this study, an oscillator model of bubble-in-water is proposed to analyze the effective modulus of low-concentration bubbly water. We show that in a wide range of wave frequency the bubbly water acquires a negative effective modulus, while the effective density of the [...] Read more.

In this study, an oscillator model of bubble-in-water is proposed to analyze the effective modulus of low-concentration bubbly water. We show that in a wide range of wave frequency the bubbly water acquires a negative effective modulus, while the effective density of the medium is still positive. These two properties imply the existence of a wide acoustic gap in which the propagation of acoustic waves in this medium is prohibited. The dispersion relation for the acoustic modes in this medium follows Lorentz type dispersion, which is of the same form as that of the phonon-polariton in an ionic crystal. Numerical results of the gap edge frequencies and the dispersion relation in the long-wavelength regime based on this effective theory are consistent with the sonic band results calculated with the plane-wave expansion method (PWEM). Our theory provides a simple mechanism for explaining the long-wavelength behavior of the bubbly water medium. Therefore, phenomena such as the high attenuation rate of sound or acoustic Anderson localization in bubbly water can be understood more intuitively. The effects of damping are also briefly discussed. This effective modulus theory may be generalized and applied to other bubble-in-soft-medium type sonic systems. Full article

(This article belongs to the Special Issue Sonic and Photonic Crystals)

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15 pages, 3721 KiB

Open AccessArticle

Development of a Stainless Austenitic Nitrogen-Alloyed CrMnNiMo Spring Steel

by Christina Schröder, Marco Wendler, Thilo Kreschel, Olena Volkova and Andreas Weiß

Crystals 2019, 9(9), 456; https://doi.org/10.3390/cryst9090456 - 31 Aug 2019

Cited by 9 | Viewed by 3875

Abstract

The generation of a nickel-reduced, stainless spring steel strip with a thickness of 0.2 mm, producible under industrial conditions, is the aim of a transfer project together with the Institute of Metal Forming/TU BAF and the Auerhammer Metallwerk GmbH within the DFG Collaborative [...] Read more.

The generation of a nickel-reduced, stainless spring steel strip with a thickness of 0.2 mm, producible under industrial conditions, is the aim of a transfer project together with the Institute of Metal Forming/TU BAF and the Auerhammer Metallwerk GmbH within the DFG Collaborative Research Centre (CRC) 799. The spring steel strip should exhibit a tensile strength of ≥1700 MPa in work-hardened and partitioned state. The mechanical and corrosive properties of the steel strip should be equal or better than those given for 1.4310 steel (AISI 301). The article presents the results of laboratory alloys focused on the design of steel strips, which meet the requirements for a cost-effective production. The results presented relate to steel design, microstructure formation, temperature-dependent mechanical properties, and corrosion resistance. Four alloys of the type X5CrMnNiMoN16-x-4 with manganese contents of approximately 2 to 6 wt.-percent were investigated. The austenitic steel X5CrMnNiMoN16-4-4 with TRIP/TWIP effect was selected for deformation and partitioning treatments. Its deformation-induced α’-martensite formation significantly contributes to the work hardening of the steel. A short-time annealing treatment (partitioning) further increases the strength properties. Full article

(This article belongs to the Special Issue Mechanical Behaviour of Austenitic Stainless Steels)

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