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SmartMat 2023年第3期4卷 120-132页

作者： Feifan Chen Yadong Zhang Lijun Hu Lifang Zheng Feiyue Ge Changsheng Feng Dan Xu Chen‐Lei Tao Xue‐Jun Wu State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjingChina

The crystal phases are essential to the physicochemical properties and functionalities of materials.Copper selenide has emerged as an important and appealing semiconductor,which can exist in a variety of polymorphic phases.However,the richness of polymorphs also makes it a challenge to the direct preparation of copper selenide nanocrystals with tunable phases.Herein,two polymorphs,that is,quasitetragonal Cu2−xSe nanocubes and metastable wurtzite Cu2Se nanodisks,are successfully synthesized by using a single precursor,copper(I)selenocyanate(CuSeCN),as the Cu and Se sources.The key to phase modulation is the optimal choice of the ligand in the synthesis.The as‐prepared nanocrystals possess different morphologies and compositions,giving rise to distinct optical properties and electrical conductivities.Interestingly,the copper selenide nanocrystals can provide a platform for the rational construction of two types of amorphous hollow Au─Cu─Se nanostructures by reaction with Au(I)precursor,in which their final shapes are well kept as that of the original nanocrystal templates.This work provides an easy strategy for the phase‐controlled synthesis of copper selenide nanocrystals and enables the design of new materials for broad applications.

关键词： amorphous copper selenides hollow nanostructures metastable polymorphs

Recent advances in photofunctional polymorphs of molecular materials

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Chinese Chemical Letters 2019年第11期30卷 1908-1922页

作者： Bo Lu Shuya Liu Dongpeng Yan Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal University

Recently,molecule-based luminescent materials have been drawing extensive attention due to their desirable properties and promising applications in the fields of sensors,lighting display and cell imaging.Crystalline polymorph is an intriguing phenomenon that the presence of multiple packing and aggregate architectures of the same molecular system.The studies on polymorphs for molecule-based fluorophores provide the opportunities to adjust the mode of molecular packing and photophysical properties,which will help to illustrate the structure-property relationship.In this review,we focus on the recent progress in various feasible methods of molecule-based crystalline polymorphism growth and their adjustable photofunctional properties,which will open up possibilities of variant optical applications.Firstly,several effective ways to prepare and screen polymorphs are sorted out.And then,we discuss the discrepant properties and multifunctional applications(such as sensors,laser and OFET).Finally,the development trends and future prospects of these polymorphs are also briefly introduced.

关键词： polymorphs Organic molecular materials Luminescence Crystalline Preparation Optical applications Structure-property relationship

Investigation of physicochemical properties and in-vitro in-vivo evaluation of agomelatine polymorphs

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Asian Journal of Pharmaceutical Sciences 2013年第3期8卷 181-190页

作者： Wei Du Yuefang Zhou Yafei Gong Chunshun Zhao Sun Yat-sen University Guangzhou 510006China

In the present study,Form I,Form II and Form III of agomelatine were prepared to investigate the variability of polymorphs,then the in-vitro in-vivo correlation were established.The presence of three polymorphs of agomelatine was corroborated through studies by XRPD,TGA and DSC.All the forms obtained were then subjected to the powder and intrinsic dissolution tests.The IDR ranked in the order of Form III>Form I>Form II.Form I and Form III both underwent solvent-mediated phase transformation(SMPT)to Form II during dissolution and the transition points were 62 and 45 min,respectively.Pharmacokinetic profiles were acquired after oral administration of tablets,showing that the ka and AUC0e12 h of Form I,Form II,Form III were 0.580.11,0.340.05,0.740.07 h1 and 296.2549.39,186.0545.93,331.1654.74 ng*h/ml,respectively.Good linearities between IDR and ka,IDR and AUC were established,suggesting that the agomelatine polymorphic forms with faster dissolution rates in-vitro would increase the rate and extent of oral absorption in-vivo.These results demonstrated that IDR was predictive in estimating the relative bioavailability of agomelatine polymorphic forms.

关键词： Agomelatine polymorphs Intrinsic dissolution rate Pharmacokinetics IVIVC

界面工程用于提高CoP-Co_(2)P多晶型物在全pH值析氢反应和碱性全解水反应中的电催化性能

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Science China Materials 2022年第9期65卷 2433-2444页

作者：陈蕾任金涛袁忠勇 Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) National Institute for Advanced MaterialsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China

开发具有丰富活性位点和高本征活性的磷化钴催化剂,用于高效且稳定的析氢反应(HER)和析氧反应(OER)具有重要意义.本工作通过精准地控制球形膦酸钴的热还原温度合理地构建了新型的碳包裹的CoP-Co_(2)P多晶型物.独特的多级孔结构和CoP-Co_... 详细信息

开发具有丰富活性位点和高本征活性的磷化钴催化剂,用于高效且稳定的析氢反应(HER)和析氧反应(OER)具有重要意义.本工作通过精准地控制球形膦酸钴的热还原温度合理地构建了新型的碳包裹的CoP-Co_(2)P多晶型物.独特的多级孔结构和CoP-Co_(2)P之间的异质界面不仅提高了活性位点的数量,而且还保证了优异的内在催化活性.所制备的催化剂展现出优异的电催化活性和稳定性(对于全pH值HER(0.5 mol L^(-1) H_(2)SO_(4):81 mV@10 mA cm^(-2);1.0 mol L^(-1) KOH:109 mV@10 mA cm^(-2);1.0 mol L^(-1) PBS:227 mV@10 mA cm^(-2))和碱性OER(1.0 mol L^(-1) KOH:1.53 V@10 mA cm^(-2))).在作为双电极电解槽中全解水反应的双功能电催化剂时,该材料可以在1.60 V的低电压下,1.0 mol L^(-1) KOH电解液中提供10 mA cm^(-2)的电流密度.本文还详细研究了CoP-Co_(2)P多晶型物在催化反应过程中的结构析出.本工作为用于各种电化学技术中的高效且价格合理的金属磷化物的设计和制备提供了一种新的方法.

关键词： cobalt phosphides polymorphs heterointerface hydrogen evolution oxygen evolution

Physics, chemistry, and Hirshfeld surface analyses of gamma-irradiated thalidomide to evaluate behavior under sterilization doses

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Journal of Pharmaceutical Analysis 2018年第3期8卷 194-201页

作者： Valner A.F.S.N.Mussel Max R Ferreira Maria B.E Marques Maria I.Yoshida Mariana R.Almeida Bernardo L.Rodrigues Wagner N.Mussel Departamento de Quimica ICExUniversidade Federal de Minas Gerais-UFMGAv.Antonio Carlos 662731270-901 Belo HorizonteMGBrazil CNEN-CDTN Comissao Nacional de Energia Nuclear-Centro de Desenvolvimento da Tecnologia NuclearAv.Antonio Carlos6627 Belo HorizonteMGBrazil

Thalidomide was indicated as a sedative and antiemetic and prescribed for pregnant women. Its tragic teratogenic effects culminated in withdrawal from the market. Since the discovery of its anti-angiogenic and anti-inflammatory actions, thalidomide has been used in the treatment of leprosy and multiple myeloma, which justify studies of its stability. We investigated the effects of irradiation of thalidomide up to 100 kGy （fourfold the usual sterilizing dose for pharmaceutics）. The polymorph of thalidomide was obtained in an isothermal experiment at 270℃. All samples underwent gamma irradiation for specific times. At different doses, decomposition of the pharmaceutical was not observed up to 100 kGy. The observed effect was angle turning between the phthalimide and glutarimide rings modulated by repulsion towards the carbonyl group, leading to a stable energetic configuration, as measured by the equilibrium in the torsion angle after irradiation. The thalidomide molecule has a center of symmetry, so a full turn starting from 57.3° will lead to an identical molecule. Further irradiation will start the process again. Samples irradiated at 30 and 100 kGy have more compact unit cells and a lower volume, which leads to an increase in the intermolecular hydrogen interaction within the unit cell, resulting in higher thermal stability for polymorph α.

关键词： Thalidomide Thermal stability polymorphs Gamma irradiation Hirshfeld

Texture Induced by Molecular Weight Dispersity: Polymorphism within Poly(L-lactic acid) Spherulites

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Chinese Journal of Polymer Science 2020年第12期38卷 1365-1373页

作者： Da-Peng Hu Min Chen Yu-Hui Yang Han-Ying Li Ministry of Education Key Laboratory of Macromolecular Synthesis and Funtinalizatin Department of Polymer Science and EngineeringZhejing UniversityHangzhou 310027 China

Poly(L-lactic acid)(PLLA)has drawn much attention due to its excellent medical and pharmaceutical applications for decades.As a semi-crystalline polymer,morphology and crystal structure of PLLA greatly determine its properties.Here,w e demonstrate,for PLLA films,a nonconventional texture featuring two types of spherulites emerging in pairs to form a distinct nested structure where a small spherulite(〜10μm)is embedded in a large one(100μm to 300μm).In addition to the size,the molecular weight and polymorph are different in the large and small spherulites.Crystallographic a-form and relatively low molecular weight are identified in the large spherulites,while meta-stable a'-form and relatively high molecular weight in the small ones.These differences suggest that the polydisperse PLLA polymers fractionate during film formation and the high-molecular-weight fraction crystallizes into the small spherulites with meta-stable structure because of its complicated polymer entanglement and high viscosity.In contrast,the rest of polymers crystallize into the large spherulites with the thermodynamically stable polymorph.Furthermore,this texture exhibits accelerated PLLA degradation initiated from the small spherulites,which is distinct from the typical PLLA spherulites.Insights provided by this work may lead to new texture-properties relationship associated with polydispersity of molecular weight.

关键词： PLLA Spherulite polymorphs Molecular weight

Manipulation of successive crystalline transformations to control electron transfer and switchable functions

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National Science Review 2018年第4期5卷 507-515页

作者： Cheng-Qi Jiao Wen-Jing Jiang Yin-Shan Meng Wen Wen Liang Zhao Jun-Li Wang Ji-Xiang Hu Gagik G.Gurzadyan Chun-Ying Duan Tao Liu State Key Laboratory of Fine Chemicals Dalian University of Technology Institute of Artificial Photosynthesis State Key Laboratory of Fine Chemicals Dalian University of Technology

Electron transfer in solid is crucial to switchable magnetic,electrical,optical and mechanical properties.However,it is a formidable challenge to control electron-transfer behaviors via manipulation of crystalline phases,especially through dynamic crystalline transformation.Herein,three crystalline phases of an{Fe2Co2}compound were obtained via enhancement of intermolecularπ···πinteractions inducingsuccessive single-crystal-to-single-crystal transformations,from solvated 1·2CH3OH·4H2O,to desolvated1 and its polymorph 1a accompanying electron transfer.1·2CH3OH·4H2O showed thermally inducedreversible intermetallic electron transfer in mother liquor.No electron-transfer behavior was observed in 1.1a showed reversible intermetallic electron transfer upon thermal treatment or alternative irradiation with808-and 532-nm lasers at cryogenic temperatures.The electron-transfer behaviors significantly change the magnetic and optical properties,providing a strategy to realize different electron-transfer behaviors andswitchable functions viaπ···πinteractions manipulated dynamic crystalline transformation.

关键词： electron-transfer dynamic structural transformation successive crystalline transformations reversible polymorphs

Taxonomic Analysis and Ecological Features of the Algal Flora of the Water Bodies of the West Zarafshan Range

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American Journal of Plant Sciences 2023年第5期14卷 542-551页

作者： Beknazar Sayfullayevich Dustov Yigitali Shavkatillayevich Tashpulatov Samarkand State University Samarkand Uzbekistan Samarkand Branch of Tashkent State Agrarian University Samarkand Uzbekistan

There are a number of reservoirs in the West Zarafshan Range, which have their own water-saturated, hydrographic, soil and ecological features. In this regard, their algoflora is also formed in its own way. As a result of research in this area, 217 species of algae were identified, belonging to 5 divisions, 11 classes, 37 orders, 57 families and 97 genera. The development and distribution of organisms in water is influenced by a number of external factors, such as: temperature, light, mineral and organic substances, active-reactive water environment, gas regime (oxygen, carbon dioxide, hydrogen sulfide), flow rate, change in water volume, degree transparency and wave formation.

关键词： Western Zarafshan Reservoirs Algal Flora Taxa Eurytherms Stenotherms polymorphs

Formation of Calcium Carbonate polymorphs Induced by Living Microalgae

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Journal of Biomaterials and Nanobiotechnology 2012年第4期3卷 413-420页

作者： Giulia Santomauro Johannes Baier Wanjing Huang Stefan Pezold Joachim Bill Institute for Materials Science University of Stuttgart Stuttgart Germany

Calcium carbonate (CaCO3) occurs in the three polymorphs calcite, aragonite and vaterite. The formation of these crystals in inorganic solutions is influenced by parameters like pH, temperature or impurities. Living freshwater microalgae can also induce the formation of CaCO3 when they live in a suitable environment containing saturated amounts of Ca2+. Through this biologically induced biomineralization only the formation of the polymorph calcite has been reported yet. We investigated the precipitates which have been formed in solutions containing the freshwater microalgae Scenedesmus obliquus and different zinc amounts (0, 3.27 and 6.53 mg Zn2+/l) by XRD and SEM. As references precipitates from the same solutions but without algae were investigated. We could show that the presence of living microalgae has a great influence on the precipitation of calcium carbonate crystals. In algae-containing media without or with a low zinc amount always calcite and aragonite are formed. In the corresponding medium with 6.53 mg Zn2+/l pure aragonite crystals were built. In contrast, in the inorganic, algae-free solutions without zinc, pure calcite is precipitated. Both inorganic solutions with zinc show major calcite precipitation and weak aragonite precipitation. Thus the algae cells advance significantly the formation of aragonite, which is enhanced by the presence of zinc cations in the media. Possible mechanisms are discussed.

关键词： CaCO3 polymorphs Biomineralization Zinc Microalgae XRD

A practical guide to pharmaceutical polymorph screening & selection

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Asian Journal of Pharmaceutical Sciences 2014年第4期9卷 163-175页

作者： Eun Hee Lee College of Pharmacy Korea University2511 Sejong-roSejong 339-700Republic of Korea

Prevalence and importance of polymorphism occurring in pharmaceutical compounds are well recognized.It is of great importance to prepare and select the right form from the beginning during drug discovery and development.This review introduces the basic concepts of“What is polymorphism?”,addresses a fundamental question of“Why do polymorphs form?”,and provides practical guidelines of“How to prepare polymorphs?”“How to evaluate the relative thermodynamic stability between polymorphs?”,and“How to analyze polymorphs?”.Moreover,case studies of pharmaceutically important polymorphs are provided.

关键词： polymorphs Polymorph screening Polymorph selection Polymorph preparation