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Chinese Physics B 2022年第3期31卷 299-305页

作者：赵壮壮荀孟潘冠中孙昀周静涛吴德馨 Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China

The 808-nm vertical cavity surface emitting laser(VCSEL) with strained In_(0.13)Ga_(0.75)Al_(0.12)As/Al_(0.3)Ga_(0.7)As quantum wells is designed and fabricated. Compared with the VCSELs with Al_(0.05)Ga_(0.95)As/Al_(0.3)Ga_(0.7)As quantum wells, the VCSEL with strained In_(0.13)Ga_(0.75)Al_(0.12)As/Al_(0.3)Ga_(0.7)As quantum wells is demonstrated to possess higher power conversion efficiency(PCE) and better temperature stability. The maximum PCE of 43.8% for 10-μm VCSEL is achieved at an ambient temperature of 30°C. The size-dependent thermal characteristics are also analyzed by characterizing the spectral power and output power. It demonstrates that small oxide-aperture VCSELs are advantageous for temperature-stable performance.

关键词： 808-nm VCSEL InGaAlAs/AlGaAs quantum wells thermal property

Synthesis, Crystal Structure and thermal property of a Manganese(II) 4-Carboxyphenoxyacetate Complex

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Chinese Journal of Structural Chemistry 2005年第3期24卷 334-338页

作者：霍丽华高山刘继伟谷长生赵辉赵经贵 SchoolofChemistryandMaterialsScience HeilongjiangUniversityHarbin150080China

The manganese(II) complex, [Mn(phen)2(4-CPOA)(H2O)]?5H2O (4-CPOAH2 = 4- carboxyphenoxyacetic acid) has been synthesized and characterized by elemental analyses, IR, TG and single-crystal X-ray diffraction. The crystal is of monoclinic, space group C2/c, with a = 27.471(3), b = 18.490(4), c = 14.507(3) ?, β = 115.13(3)o, V = 6671(3) ?3, Z = 8, Mr = 717.58, Dc= 1.429 g/cm3, μ = 0.462 mm–1, F(000) = 2984, the final R = 0.0535 and wR = 0.1200 for 5413 observed reflections with I > 2σ(I). The Mn(II) atom is coordinated by one O atom of 4-carboxy- phenoxyacetate, four N atoms of two 1,10-phenanthroline and one water molecule, residing in a distorted octahedral environment. A supramolecular network structure is formed by hydrogen bonds and π-π stacking interactions.

关键词： manganese (II) carboxylate complex crystal structure thermal property

An Explosive Organic/Inorganic Hybrid: Synthesis and thermal property of Octa(2,4-dinitrophenyl)silsesquioxane

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Chemical Research in Chinese Universities 2004年第1期20卷 42-45页

作者： CHENHong-Ji DepartmentofChemistry JinanUniversityGuangzhou510632P.R.China

Octaphenylsilsesquioxane(OPhS) was prepared by a modifying method and a new core-shell nanocomposite, octa(2,4-dinitrophenyl)silsesquioxane, [(R_2PhSiO_ 1.5)_8, R=—NO_2, ODNPhS], was synthesized by nitration of OPhS in a mixed acid solution of nitric and sulfuric acids at about 60 ℃. Their molecular structures were determined by DRIFTS, 1H NMR, 13C NMR spectra analysis. The thermal analysis shows that ODNPhS is an explosive that detonates at about 420 ℃.

关键词： Core-shell nanocomposite Organic/inorganic hybrid Octa(2,4-dinitrophenyl)silsquioxane thermal property

Design and experimental performance verification of a thermal property test-bed for lunar drilling exploration

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Chinese Journal of Aeronautics 2016年第5期29卷 1455-1468页

作者： Zhang Tao Zhao Zeng Liu Shuting Li Jinglin Ding Xilun Yin Shen Wang Guoxin Lai Xiaoming School of Mechanical Engineering and Automation Beihang University Beijing 100083 China China Academy of Space Technology Beijing 100094 China

Chinese Chang＇e lunar exploration project aims to collect and return subsurface lunar soil samples at a minimum penetration depth of 2 m in 2017. However, in contrast to those on the Earth, automated drilling and sampling missions on the Moon raise the risk of burning bits. Test-beds are required for testing the thermal properties of drill tools in a lunar environment. In this paper, a novel temperature measuring method based on thermocouples and a slip ring was proposed. Furthermore, a data acquisition system for a drilling process was designed. A vacuous, cryogenic, and anhydrous soil environment simulating the lunar surface was established. A drilling test-bed that can reach a depth of 2.2 m was developed. A control strategy based on online monitoring signals was proposed to improve the drilling performance. Vacuum and non-vacuum experiments were performed to test the temperature rising effect on drill tools. When compared with the non-vacuum experiment, the vacuum temperature rise resulted in a 12 ℃ increase. These experimental results provide significant support for Chinese lunar exploration missions.

关键词： Drilling test bed Lunar drill Lunar environment simulator Temperature measurement thermal property

Synthesis,Crystal Structure and thermal property of a 2D Brick Wall Framework Constructed from a New Mononuclear Complex

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Chinese Journal of Structural Chemistry 2010年第9期29卷 1321-1326页

作者：张云张士真李建定党娟陶偌偈 Institute of Molecular & Crystal Engineering Chemistry and Chemical Engineering CollegeHenan University Shangqiu Technician College

One new coordination polymer with the chemical formula [CoCu2L2·K2·1.5C2H5OH]n（H4L = 2-hydroxy-3-[（E）-（{3-[（2-hydroxybenzoyl）amino]propyl}imino）methyl] benzoic acid） has been synthesized based on the slow diffusion method,and characterized by IR spectroscopy,thermalgravimetric and X-ray diffraction analysis.It crystallizes in the monoclinic system,space group P21/n with a = 11.98860（10）,b = 24.4279（3）,c = 14.9008（2） ,β = 104.7490（10）°,V = 4220.01（8） 3,Z = 2,Mr = 1009.94,Dc = 1.590 g/cm3,F（000） = 2056,μ（MoKα） = 1.649 mm-1,the final R = 0.0411 and wR = 0.1178 for 5920 observed reflections with I 2σ（I）.The compound possesses a 2D brick wall structure constructed from trinuclear units.

关键词： coordination polymer crystal structure brick wall thermal property

Synthesis, Crystal Structure and thermal property of Dimethyl Phenanthrene-9,10-dicarboxylate

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Chinese Journal of Structural Chemistry 2020年第5期39卷 908-912页

作者：罗再刚刘倩男李蕊徐雪梅 College of Chemical Engineering Anhui University of Science and TechnologyHuainan 232001China

The target compound(C18H14O4)was synthesized and structurally determined by single-crystal X-ray diffraction.The crystal is of monoclinic system,space group P21/n with a=7.9383(6),b=19.5083(13),c=9.4189(7)?,β=98.981(2)°,C18H14O4,Mr=294.29,Dc=1.357 g/cm^3,V=1440.75(18)?3,Z=4,F(000)=616,μ(MoKa)=0.096 mm-1,T=293(2)K,3320 independent reflections with 1845 observed ones(I>2σ(I)),R=0.0529 and wR=0.1082 with GOF=1.015(R=0.1202 and wR=0.1278 for all data).The phenanthrene skeleton is coplanar.The overall crystal packing revealed that it has reverse staggered parallel and stratified arrangement.And a one-dimensional interaction model was formed by two kinds ofπ-πinteractions between the two adjacent molecules at upper and lower levels.The decomposition mechanism of compound 3 is complex.

关键词： phenanthrene synthesis crystal structure thermal property

Crystal Structure and thermal property of 4-(3-Chlorophenyl)-3-isopropyl-1-methyl-3,4-dihydroquinolin-2(1H)-one

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Chinese Journal of Structural Chemistry 2020年第5期39卷 913-917页

作者：李慧娟罗再刚王秀秀 Department of Pharmaceutical Engineering Bengbu Medical CollegeBengbu 233030China College of Chemical Engineering Anhui University of Science and TechnologyHuainan 232001China

The target compound(C19H20ClNO)was structurally determined by single-crystal X-ray diffraction.The crystal is in monoclinic system,space group P21/n with a=9.2365(2),b=12.1241(3),c=14.9960(4)?,β=106.589(3)°,C19H20ClNO,Mr=313.81,Dc=1.295 g/cm^3,V=1609.42(7)?3,Z=4,F(000)=664,μ(MoKa)=2.097 mm-1,T=200(10)K,2813 independent reflections with 2533 observed ones(I>2σ(I)),R=0.0389 and wR=0.1057 with GOF=1.043(R=0.0423 and wR=0.1083 for all data).The 3,4-dihydroquinolin-2(1 H)-one moiety maintains thermodynamically stable trans configuration.The decomposition mechanism of compound 3 is complex by thermal analysis.

关键词： 3 4-dihydroquinolin-2(1H)-one crystal structure thermal property

thermal property, MISCIBILITY AND CRYSTALLIZATION BEHAVIOR OF POLY(3-HYDROXYBUTYRATE-co-3-YDROXYHEXANOATE) AND POLY(BUTYLENE SUCCINATE-ADIPATE) (PHBHHX/PBSA) BLENDS

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Chinese Journal of Reactive Polymers 2005年第Z1期 1-7页

作者： WANG Shufang1 GUO Tianying1 TAO Jian2 ZHENG Chenggang2 ZHANG Banghua1 SONG Cunjiang2** 1 Key Laboratory of Functional Polymer Materials for Ministry of Education Institute of Polymer Chemistry, Nankai University, Tianjin 300071, China 2 Key Laboratory of Bioactive Materials for Ministry of Education, Department of Microbiology, Life Science College, Nankai University, Tianjin 300071, China

Blends of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and poly(butylene succinate-adipate) (PBSA), both biodegradable semicrystalline polyesters, were prepared with the ratio of PHBHHx/PBSA ranging from 80/20 to 20/80 by melt mixing method. Differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), dynamic mechanical thermal analysis (DMA), polarizing optical microscopy (POM) and wide angle X-ray diffractometer (WAXD) were used to study the miscibility and crystallization behavior of PHBHHx/PBSA blends. Experimental results indicate that PHBHHx is immiscible with PBSA as shown by the almost unchanged glass transition temperature and the biphasic melt.

关键词： Poly(3-hydroxybutyrate-co-hydroxyhexanoate)/poly(butylenes succinate-adipate) blends thermal property Miscibility Crystallization.

Preparation and thermal Properties of a Novel Modified Ammonium Alum/Expanded Graphite Composite Phase Change Material

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Journal of thermal Science 2023年第6期32卷 2093-2103页

作者： YIN Shaowu HAN Jiawei ZHANG Chao KANG Peng TONG Lige WANG Li School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Energy Saving and Emission Reduction University of Science and Technology BeijingBeijing100083China

thermal energy storage(TES)using phase change materials(PCMs)is a powerful solution to the improvement of energy efficiency.The application of Ammonium alum(A-alum,NH4Al(SO_(4))_(2)·12H_(2)O)in the latent thermal energy storage(LTES)systems is hampered due to its high supercooling and low thermal conductivity.In this work,modified A-alum(M-PCM)containing different nucleating agents was prepared and further adsorbed in expanded graphite(EG)to obtain composite phase change material(CPCM)to overcome the disadvantages of A-alum.thermal properties,thermal cycle stability,microstructure and chemical compatibility of CPCM were characterized by differential scanning calorimetry,thermal constant analysis,scanning electron microscopy,X-ray diffraction and Fourier transform infrared spectroscopy.The cold rewarming phenomenon of CPCM was established and explained.Results showed that the latent heat and melting point of CPCM were 187.22 J/g and 91.54℃,respectively.The supercooling of CPCM decreased by 9.61℃,and thermal conductivity increased by 27 times compared with pure A-alum.Heat storage and release tests indicated that 2 wt%calcium chloride dihydrate(CCD,CaCl_(2)·2H_(2)O)was the optimum nucleating agent for A-alum.The result of TG and 30 thermal cycles revealed that CPCM exhibited favorable thermal stability and reliability during the operating temperature.The prepared modified A-alum/EG CPCM has a promising application prospect for LTES.

关键词： composite phase change material thermal property ammonium alum expanded graphite supercooling thermal conductivity

High-entropy rare-earth diborodicarbide:A novel class of high-entropy(Y_(0.25)Yb_(0.25)Dy_(0.25)Er_(0.25))B_(2)C_(2)ceramics

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Journal of Advanced Ceramics 2023年第7期12卷 1430-1440页

作者： Huidong Xu Longfei Jiang Ke Chen Qing Huang Xiaobing Zhou Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China

A novel class of high-entropy rare-earth metal diborodicarbide(Y_(0.2)5 Yb_(0.25)Dy_(0.25)Er_(0.25))B_(2)C_(2)(HE-REB_(2)C_(2))ceramics was successfully fabricated using the in-situ reactive spark plasma sintering(SPS)technology for the first time.Single solid solution with a typical tetragonal structure was formed,having a homogeneous distribution of four rare-earth elements,such as Y,Yb,Dy,and Er.Coefficients of thermal expansion(CTEs)along the a and c directions(aa and ac)were determined to be 4.18 and 16.06μK^(-1),respectively.thermal expansion anisotropy of the as-obtained HE-REB_(2)C_(2)was attributed to anisotropy of the crystal structure of HE-REB_(2)C_(2).The thermal conductivity(k)of HE-REB_(2)C_(2)was 9.2±0.09 W·m^(-1)·K^(-1),which was lower than that of YB_(2)C_(2)(19.2±0.07 W·m^(-1)·K^(-1)),DyB_(2)C_(2)(11.90.06 W·m^(-1)·K^(-1)),and ErB_(2)C_(2)(12.10.03 W·m^(-1)·K^(-1)),due to high-entropy effect and sluggish diffusion effect of high-entropy ceramics(HECs).Furthermore,Vickers hardness of HE-REB_(2)C_(2)was slightly higher than that of REB_(2)C_(2)owing to the solid solution hardening mechanism of HECs.Typical nano-laminated fracture morphologies,such as kink boundaries,delamination,and slipping were observed at the tip of Vickers indents,suggesting ductile behavior of HE-REB_(2)C_(2).This newly investigated class of ductile HE-REB_(2)C_(2)ceramics expanded the family of HECs to diboridcarbide compounds,which can lead to more research works on high-entropy rare-earth diboridcarbides in the near future.

关键词： high-entropy rare-earth diboridcarbide (Y_(0.25)Yb_(0.25)Dy_(0.25)Er_(0.25))B_(2)C_(2)(REB_(2)C_(2)) high-entropy ceramics(HECs) thermal property damage tolerance