Journal of Applied Crystallography最新文献_第9页

A science-driven approach to optimize the design for a biological small-angle neutron scattering instrument 以科学为导向的生物小角中子散射仪器优化设计方法

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-31 DOI: 10.1107/S1600576724004254

Christoph U. Wildgruber, Shuo Qian, Serena H. Chen, Kenneth W. Herwig, Volker S. Urban, Hugh O'Neill

{"title":"A science-driven approach to optimize the design for a biological small-angle neutron scattering instrument","authors":"Christoph U. Wildgruber, Shuo Qian, Serena H. Chen, Kenneth W. Herwig, Volker S. Urban, Hugh O'Neill","doi":"10.1107/S1600576724004254","DOIUrl":"https://doi.org/10.1107/S1600576724004254","url":null,"abstract":"Biological small-angle neutron scattering (SANS) instruments facilitate critical analysis of the structure and dynamics of complex biological systems. However, with the growth of experimental demands and the advances in optical systems design, a new neutron optical concept is necessary to overcome the limitations of current instruments. This work presents an approach to include experimental objectives (i.e. the science to be supported by a specific neutron scattering instrument) in the optimization of the neutron optical concept. The approach for a proposed SANS instrument at the Second Target Station of the Spallation Neutron Source at Oak Ridge National Laboratory, USA, is presented here. The instrument is simulated with the McStas software package. The optimization process is driven by an evolutionary algorithm using McStas output data, which are processed to calculate an objective function designed to quantify the expected performance of the simulated neutron optical configuration for the intended purpose. Each McStas simulation covers the complete instrument, from source to detector, including realistic sample scattering functions. This approach effectively navigates a high-dimensional parameter space that is otherwise intractable; it allows the design of next-generation SANS instruments to address specific scientific cases and has the potential to increase instrument performance compared with traditional design approaches.","PeriodicalId":48737,"journal":{"name":"Journal of Applied Crystallography","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141251525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Polar orientation and extension in a novel crystallographic model for PbTiO3-based perovskites explaining the experimental ferroelectric thermal anomalies 解释实验铁电热异常的基于 PbTiO3 的包晶的新型晶体学模型中的极性取向和延伸

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-31 DOI: 10.1107/S1600576724003686

Flávia Regina Estrada, Ariel Moreno-Gobbi, Dragan Damjanovic, Ducinei Garcia

{"title":"Polar orientation and extension in a novel crystallographic model for PbTiO3-based perovskites explaining the experimental ferroelectric thermal anomalies","authors":"Flávia Regina Estrada, Ariel Moreno-Gobbi, Dragan Damjanovic, Ducinei Garcia","doi":"10.1107/S1600576724003686","DOIUrl":"https://doi.org/10.1107/S1600576724003686","url":null,"abstract":"PbTiO3-based ferroelectric solid-solution ceramics have been widely used for electromechanical devices. However, it is still challenging to separate and control the contributions to the electromechanical functionalities, mainly as a function of temperature, where thermal anomalies and phase transitions can be observed. This study investigates the ultrasonic velocity and attenuation and the dielectric, ferroelectric and structural features of Pb0.55Ca0.45TiO3 ceramics from low temperatures (10 or 115 K) up to room temperature as an example of A-site isovalent substitution in PbTiO3. Such a combination of information makes possible the phenomenological deconvolution of the effects of ferroelectric domain wall pinning and structural features on spontaneous electric polarization. The room-temperature symmetry was determined as Pna21. The results show that this model refined by the Rietveld method for synchrotron X-ray diffraction patterns from 115 K to room temperature can explain the polarization extension features of these materials during heating. This study shows a correlation between structural thermal anomalies and low-temperature electric polarization in PbTiO3-based ferroelectric ceramics.","PeriodicalId":48737,"journal":{"name":"Journal of Applied Crystallography","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141251437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Denoising an X-ray image by exploring the power of its physical symmetry 通过探索物理对称性的力量对 X 射线图像去噪

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-24 DOI: 10.1107/S1600576724002899

Zhongzheng Zhou, Chun Li, Longlong Fan, Zheng Dong, Wenhui Wang, Chen Liu, Bingbing Zhang, Xiaoyan Liu, Kai Zhang, Ling Wang, Yi Zhang, Yuhui Dong

{"title":"Denoising an X-ray image by exploring the power of its physical symmetry","authors":"Zhongzheng Zhou, Chun Li, Longlong Fan, Zheng Dong, Wenhui Wang, Chen Liu, Bingbing Zhang, Xiaoyan Liu, Kai Zhang, Ling Wang, Yi Zhang, Yuhui Dong","doi":"10.1107/S1600576724002899","DOIUrl":"10.1107/S1600576724002899","url":null,"abstract":"Next-generation light source facilities offer extreme spatial and temporal resolving power, enabling multiscale, ultra-fast and dynamic characterizations. However, a trade-off between acquisition efficiency and data quality needs to be made to fully unleash the resolving potential, for which purpose powerful denoising algorithms to improve the signal-to-noise ratio of the acquired X-ray images are desirable. Yet, existing models based on machine learning mostly require massive and diverse labeled training data. Here we introduce a self-supervised pre-training algorithm with blind denoising capability by exploring the intrinsic physical symmetry of X-ray patterns without requiring high signal-to-noise ratio reference data. The algorithm is more efficient and effective than algorithms without symmetry involved, including an supervised algorithm. It allows us to recover physical information from spatially and temporally resolved data acquired in X-ray diffraction/scattering and pair distribution function experiments, where pattern symmetry is often well preserved. This study facilitates photon-hungry experiments as well as in situ experiments with dynamic loading.","PeriodicalId":48737,"journal":{"name":"Journal of Applied Crystallography","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141098604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-24

引用次数: 0

The master key: structural science in unlocking functional materials advancements 万能钥匙：开启功能材料进步的结构科学

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-24 DOI: 10.1107/S1600576724003674

Sebastian A. Suarez

引用次数: 0

Effects of polyvinylpyrrolidone on the crystallization of amorphous griseofulvin: fracture and molecular mobility 聚乙烯吡咯烷酮对无定形格列齐芬结晶的影响：断裂和分子流动性

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-24 DOI: 10.1107/S1600576724003844

Yanan Wang, Chai-Yee Chin, Naveen Kumar Hawala Shivashekaregowda, Qin Shi

{"title":"Effects of polyvinylpyrrolidone on the crystallization of amorphous griseofulvin: fracture and molecular mobility","authors":"Yanan Wang, Chai-Yee Chin, Naveen Kumar Hawala Shivashekaregowda, Qin Shi","doi":"10.1107/S1600576724003844","DOIUrl":"10.1107/S1600576724003844","url":null,"abstract":"This study aims to investigate the fracture, molecular mobility and crystallization behaviors of amorphous griseofulvin (GSF) in the presence of polyvinylpyrrolidone (PVP). In the presence of 10%(w/w) PVP K90, the fracture resistance of griseofulvin was greatly improved. Compared with the pure GSF system, the average fracture temperature of the griseofulvin–PVP K90 system was decreased to approximately −6.1°C. More importantly, a statistical study revealed that the direct connection between fracture and nucleation of griseofulvin was weakened in the presence of PVP K90. This study also explored the effects of PVP K90 on the molecular dynamics and crystallization behaviors of amorphous GSF. In the presence of PVP K90, the crystal growth kinetics and molecular dynamics were both slowed down. Interestingly, needle-like crystal growth was observed, exhibiting approximately the same rates as the bubble-induced process. These findings are important for understanding the complex mechanisms of physical stability of polymer-based amorphous solid dispersions.","PeriodicalId":48737,"journal":{"name":"Journal of Applied Crystallography","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141099396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Structural and electronic properties of Mo-decorated graphene, reduced graphene and reduced graphene oxide: a DFT calculation 钼装饰石墨烯、还原石墨烯和还原氧化石墨烯的结构和电子特性：DFT 计算

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-24 DOI: 10.1107/S1600576724002061

Nazanin Mohseninia, Hamid Rezagholipour Dizaji, Nafiseh Memarian, Hossein Hajiabadi

{"title":"Structural and electronic properties of Mo-decorated graphene, reduced graphene and reduced graphene oxide: a DFT calculation","authors":"Nazanin Mohseninia, Hamid Rezagholipour Dizaji, Nafiseh Memarian, Hossein Hajiabadi","doi":"10.1107/S1600576724002061","DOIUrl":"https://doi.org/10.1107/S1600576724002061","url":null,"abstract":"The structural and electronic properties of pure graphene, graphene with a vacancy, graphene with two vacancies and molybdenum-doped graphene were investigated. In addition, the adsorption of Mo atoms on graphene (G), reduced graphene (rG) and reduced graphene oxide (rGO) was examined. The possible energies of different active adsorption sites of nanostructured Mo-decorated G, rG and rGO have been calculated using density functional theory (DFT). Mo atoms are predicted to create bonds with six C atoms in G, three C atoms in rG, and both C and O atoms in rGO sheets after geometry optimizations. The study focused on changing the electronic structure of G, including opening the zero band gap and controlling the band structure, which was done by creating defects and adding impurities. The present study revealed a significant correlation between the adsorption of the Mo atom and the characteristics exhibited by frontier orbitals. The results indicated that the adsorption characteristics of Mo atoms in pure G, rG and rGO are different, despite chemisorption being the common mechanism. Specifically, Mo-decorated rG exhibited higher adsorption energy, while Mo-decorated G demonstrated a lower adsorption energy. According to these findings, it is reasonable to anticipate that Mo-decorated rG could be applied as a novel adsorbent for the removal of pollutants.","PeriodicalId":48737,"journal":{"name":"Journal of Applied Crystallography","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141251260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-17

引用次数: 0

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-17

引用次数: 0

IF 6.1 3区材料科学

Journal of Applied Crystallography Pub Date : 2024-05-17

引用次数: 0