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A universal hydrochloric acid-assistant powder-to-powder strategy for quick and mass preparation of lead-free perovskite microcrystals

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Light(Science & Applications) 2023年第4期12卷 613-624页

作者： Huanxin Yang Xiangxiang Chen Yiyue Chu Changjiu Sun Haolin Lu Mingjian Yuan Yuhai Zhang Guankui Long Libing Zhang Xiyan Li Institute of Photoelectronic Thin Film Devices and Technology Solar Energy Conversion CenterNankai UniversityTianjin 300350China Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Nankai UniversityTianjin 300350China Engineering Research Center of Thin Film Photoelectronic Technology of Ministry of Education Nankai UniversityTianjin 300350China Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong Institute for Advanced Interdisciplinary Research(IAIR)University of JinanJinan 250022 ShandongChina Tianjin Key Laboratory of Molecular Optoelectronic Department of ChemistryTianjin UniversityTianjin 300354China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage Center(RECAST)College of ChemistryNankai UniversityTianjin 300071China Schoolof Materials Science and Engineering Nankai UniversityTianjin 300350China

Lead-free halide perovskite materials possess low toxicity,broadband luminescence and robust stability compared with conventional lead-based perovskites,thus holding great promise for eyes-friendly white light LEDs.However,the traditionally used preparation methods with a long period and limited product yield have curtailed the commercialization of these materials.Here we introduce a universal hydrochloric acid-assistant powder-to-powder strategy which can accomplish the goals of thermal-,pressure-free,eco-friendliness,short time,low cost and high product yield,simultaneously.The obtained Cs_(2)Na_(0.9)Ag_(0.1)In_(0.95)Bi_(0.05)Cl_(6)microcrystals exhibit bright self-trapped excitons emission with quantum yield of(98.3±3.8)%,which could retain(90.5±1.3)%and(96.8±0.8)%after continuous heating or ultraviolet-irradiation for 1000 h,respectively.The phosphor converted-LED exhibited near-unity conversion efficiency from ultraviolet chip to self-trapped excitons emission at~200 mA.Various ions doping(such as Cs_(2)Na_(0.9)Ag_(0.1)InCl_(6):Ln^(3+))and other derived lead-free perovskite materials(such as Cs_(2)ZrCl_(6)and Cs_(4)MnBi_(2)Cl_(12))with high luminous performance are all realized by our proposed strategy,which has shown excellent availability towards commercialization.

关键词： perovskite preparation hydrochloric

preparation process of bio-oil and bio-asphalt,their performance,and the application of bio-asphalt:A comprehensive review

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第2期7卷 137-151页

作者： Hainian Wang Ziye Ma Xi Chen Mohd Rosli Mohd Hasan School of Highway Chang'an UniversityXi'an 710064China School of Civil Engineering Universiti Sains MalaysiaNibong Tebal 14300Pulau PinangMalaysia

The objective of this paper is to establish the state of knowledge on fast pyrolysis of bio-oil and bio-asphalt binder and to facilitate efforts in improving the overall perform ance of bioasphalt and maximizing its road application.On the basis of reviewing the relevant literature recently,the fast pyrolysis(FasP) preparation process of bio-oil and its main properties,the preparation process of bio-asphalt and its performance and the application of bio-asphalt have been summarized.Due to the variations in raw materials,the adopted methods of FasP to prepare bio-oil could be different,and the properties of bio-oil from different sources are also different.At present,the plant-based bio-oil(mainly derived from wood waste and sawdust) has been widely used to prepare the bio-asphalt.Research on the low-temperature flexibility,high-temperature rheology,workability and other performance of biological asphalt showed that the workability and high-temperature performance of most asphalt are improved after adding bio-oil.However,the low-temperature performance is found to relatively reduce.Also,with regards to its application as a rejuvenator,bio-oil can considerably rejuvenate the aged asphalt’s mixture performance.By far,most of research on bio-asphalt is still focused on the performance of bio-asphalt binder in the laboratory;its application in practical road engineering is still to be examined.This review also provides an outlook for the future,for example,establishing an integrated preparation process from bio-oil to bio-asphalt,and evaluating the properties of bioasphalt by new standards.

关键词： Road engineering Bio-oil Bio-asphalt preparation process Performance Application of bio-asphalt

preparation and Molecular Structure of (SCZ)(TNPG)·2H_2O

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Chinese Journal of Structural Chemistry 2005年第8期24卷 973-979页

作者： CHEN Hong-Yan ZHANG Tong-Lai ZHANG Jian-Guo State Key Laboratory of Prevention and Control of Explosion Disasters and School of Science Beijing Institute of Technology Beijing 100081 China

The （SCZ）（TNPG）.2H2O prepared by mixing semicarbazide （SCZ） and trinitrophloroglucinol （TNPG） was characterized by elemental analysis and IR measurement, and its crystal structure was determined by X-ray single-crystal diffraction analysis. The crystal belongs to triclinic,space group P1, （NH2CONHNH3）^＋（C6H2N3O9）^-·2H2O, Mr = 372.23, a = 0.68853（14）, b =0.93966（19）, c = 1.1925（2） nm, α = 67.48（3）, β = 77.56（3）, γ = 78.93（3）°, V = 0.6908（2） nm^3, Z = 2,Dc = 1.789 g/cm^3, Mr = 373.23, F（000） = 384, S = 0.999 and μ（MoKa） = 0.172 mm^-1. The final R and wR are 0.0394 and 0.1057 for 1724 observed reflections with I 〉 2σ（I）. It is concluded that （SCZ）（TNPG） 2H2O is an ionic compound composed of a cation SCZ^＋, an anion TNPG- and two water molecules. The TNPG anion and SCZ^＋ cation are bonded together by electrostatic attraction and hydrogen bonds, and the compound structure is stable. The thermal decomposition of （SCZ）（TNPG） 2H2O was studied by using TG-DTG and DSC techniques with a heating rate of 10 ℃/min, showing the compound contains one endothermic process of dehydrating stage and two intensive exothermic decomposition stages. The enthalpy of exothermic decomposition reaction is 452.31 kJ/mol.

关键词： semicarbazide trinitrophloroglucinol preparation crystal structure

preparation OF A SINGLE PHASE R_(3)(Fe,Mo)_(29)(R=Ce,Nd,Sm,Gd,Tb,Dy AND Y)

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中国有色金属学会会刊：英文版 1998年第3期8卷 37-41页

作者： Pan Hongge Chen Weixiang Chen Yun Chen Changpin Department of Materials Science and Engineering Zhejiang UniversityHangzhou 310027P.R.China

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１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｒｅｃｅｎｔｙｅａｒｓ，ｒｅｓｅａｒｃｈｅｒｓｉｎｔｈｅｆｉｅｌｄｏｆｐｅｒｍａｎｅｎｔｍａｇｎｅｔｉｃｍａｔｅｒｉａｌｓｈａｖｅｐａｉｄｍｏｒｅａｔｔｅｎｔｉｏｎｔｏｔｈｅｎｅｗｔｙｐｅｏｆｒａｒｅｅａｒｔｈｉｒｏｎ...

关键词： 3:29 compounds preparation a single phase

preparation of SO_4^(2-)/TiO_2-WO_3 solid superacid and its catalytic activity in acetalation and ketaltion

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Rare Metals 2005年第1期24卷 22-27页

作者： YANGShuijin YUXieqing BAIAiming SUNJutang DepartmentofChemistryandEnvironmentalEngineering HubeiNormalUniversityHuangshi435002China／／CollegeofChemistryandMolecularSciencesWuhanUniversityWuhan430072China DepartmentofChemistryandEnvironmentalEngineering HubeiNormalUniversityHuangshi435002China CollegeofChemistryandMolecularSciences WuhanUniversityWuhan430072China

SO_4^(2-)/TiO_2-WO_3 was prepared and its catalytic activity under differentsynthetic conditions was discussed with esterification of n-butanoic acid and n-butyl alcohol asprobing reaction. The optimum conditions are found that the mass fraction of H_2WO_4 used in thecompound is 12.5 percent, the calcination temperature is 580 deg C, the calcination time is 3 h, andthe soaked consistency of H_2SO_4 is 1.0 mol centre dot L^(-1). Then SO_4^(2-)/TiO_2-WO_3 wasapplied as the catalyst in the catalytic synthesis of eight similar important ketals and acetalsunder the optimum conditions and revealed high catalytic activity. On condition that the molar ratioof aldehyde/ketone to glycol is 1:1.5, the mass fraction of the catalyst used in the reactants is0.5 percent, and the reaction time is 1.0 h, the yields of ketals and acetals can reach 64.2percent-95.1 percent. Moreover, it can be easily recovered and reused.

关键词： solid superacid preparation catalytic activity acetalation katalation

preparation and Microstructural Characterization of Activated Carbon-Metal Oxide Hybrid Catalysts:New Insights into Reaction Paths

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Journal of Materials Science & Technology 2015年第8期31卷 806-814页

作者： A.Barroso-Bogeat M.Alexandre-Franco C.Fernndez-Gonzlez V.Gómez-Serrano Department of Organic and Inorganic Chemistry Faculty of SciencesUniversity of Extremadura

In catalysis processes, activated carbon （AC） and metal oxides （MOs） are widely used either as catalysts or as catalyst supports because of their unique properties. A combination of AC and MO nanoparticles in a single hybrid material usually entails both chemical and microstructural changes, which may largely influence the potential catalytic suitability and performance of the resulting product. Here, the prepa- ration of a wide series of AC-MO hybrid catalysts is studied. Three series of such catalysts are prepared by support first of MO （Al2O3, Fe2O3, SnO2, TiO2, WO3, and ZnO） precursors on a granular AC by wet impregnation and oven-drying at 120 ℃, and by subsequent heat treatment at 200 or 850℃ in inert atmosphere. Both the chemical composition and microstructure are mainly investigated by powder X-ray diffraction. Yield and ash content are often strongly dependent on the MO precursor and heat treatment temperature, in particular for the Sn catalysts. With the temperature rise, trends are towards the transformation of metal hydroxides into metal oxides, crystallinity improvement, and occurrence of drastic composition changes, ultimately leading to the formation of metals in elemental state and even metal carbides. Reaction paths during the preparation are explored for various hybrid catalysts and new insights into them are provided.

关键词： Activated carbon Metal oxides Hybrid catalysts preparation Microstructural characterization X-ray diffraction

Streamlined and on-demand preparation of mRNA products on a universal integrated platform

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Microsystems & Nanoengineering 2023年第4期9卷 119-128页

作者： Hongjuan Wei Zhen Rong Liyan Liu Ye Sang Jing Yang Shengqi Wang Bioinformatics Center of AMMS Beijing 100850P.R.China

Vaccines are used to protect human beings from various diseases.mRNA vaccines simplify the development process and reduce the production cost of conventional vaccines,making it possible to respond rapidly to acute and severe diseases,such as coronavirus disease 2019.In this study,a universal integrated platform for the streamlined and ondemand preparation of mRNA products directly from DNA templates was established.Target DNA templates were amplified in vitro by a polymerase chain reaction module and transcribed into mRNA sequences,which were magnetically purified and encapsulated in lipid nanoparticles.As an initial example,enhanced green fluorescent protein(eGFP)was used to test the platform.The expression capacity and efficiency of the products were evaluated by transfecting them into HEK-293T cells.The batch production rate was estimated to be 200–300μg of eGFP mRNA in 8 h.Furthermore,an mRNA vaccine encoding the receptor-binding domain(RBD)of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)spike protein was produced by this platform.The proposed integrated platform shows advantages for the universal and on-demand preparation of mRNA products,offering the potential to facilitate broad access to mRNA technology and enable the development of mRNA products,including the rapid supply of new mRNA-based vaccines in pandemic situations and personalized mRNA-based therapies for oncology and chronic infectious diseases,such as viral hepatitis and acquired immune deficiency syndrome.

关键词： preparation template offering

preparation and Properties of PBXs Based on FOX-7 in Controlled Fragmentation Warhead Application

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含能材料 2018年第10期26卷 843-849页

作者： Karim K Elsharkawy Lin Guo Ahmed M Enew School of Chemistry and Environment Beijing University of Aeronautics and Astronautics Chemical Department Faculty of EngineeringCairo University

Polymer bonded explosive(PBX)formulations were successfully prepared in the laboratory scale containing 1,1-diamino-2,2-dinitroethene(FOX-7)and hexogen(RDX)as brisant high explosives and different binder types of polyurethane(PU)based on glycidyl azide polymer(GAP) and hydroxyl-terminated polybutadiene(HTPB) as an energetic and inert polymeric binder respectively.Casting technique was used for the preparation of different PBX formulations based on FOX-7/RDX and PU(GAP/HTPB)with 14% binder.The sensitivity to different initial impulses and performance characteristics of the explosive and lethal zone of the tested controlled fragmentation warhead by the fragmentation warhead assessment test(arena test)were studied,in which the arena test was carried out with a controlled fragmentation warhead made from Ck45 steel,with dimensions(100 mm length,30 mm outer diameter and 3 mm thickness).Results show that PBXGF4 has lower sensitivity to impact and heat than those of PBXGR4 by 188.4% and 3.2% respectively.Its friction sensitivity is the same as that of PBXGR4.It has better performance,in which detonation velocity increases by 2.1% and brisance increases by 0.5% when compared with those of PBXGR4.It was concluded that PBXGF4 which based on FOX-7 bonded with PU/GAP matrix has good characteristics as PBX,specially in the sensitivity to impact and can be applied for replacing PBXs based on RDX in the advanced PBXs for low sensitive fragmentation warheads.

关键词： polymer bonded explosive(PBX) controlled fragmentation warhead 1,1-diamino-2,2-dinitroethene(FOX-7) hexo-gen(RDX) preparation sensitivity performance characterization arena test

preparation of scandia stabilized zirconia powder using microwave-hydrothermal method

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Journal of Rare Earths 2015年第7期33卷 746-751页

作者：敖红敏刘向生张赫周静黄小卫冯宗玉徐宏 Grirem Advanced Materials Co. Ltd. National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals

Scandia stabilized zirconia powder （ScSZ） was first synthesized by a microwave-hydrothermal method. The crystalline and aggregated particle sizes were investigated by means of X-ray diffraction （XRD）, Raman, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Weakly agglomerated and well crystallized ScSZ powder was prepared by microwave-heating to 150 ℃ and 2.5 h. The structure of the ScSZ powder changed from a tetragonal to a cubic phase, and accordingly, the powder conductivity was increased from 90.55 to 120.56 ms/cm by the introduction of the mineralizer solutions （KOH＋K2CO3） during the microwave-hydrothermal processing.

关键词： scandia stabilized zirconia preparation microwave-hydrothermal mineralizer rare earths