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Synthesis and thermal properties of poly(styrene-co-acrylonitrile)-graft-polyethylene glycol copolymers as novel solid–solid phase change materials for thermal energy storage

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Chinese Chemical Letters 2015年第11期26卷 1364-1366页

作者： si-yang Mu Jing Guo Yu-Mei Gong Sen Zhang Yue Yu School of Textile and Material Engineering Dalian Polytechnic University Liaoning Engineering Technology Research Centre of Function Fiber and Its Composites

A novel poly（styrene-co-acrylonitrile）-graft-polyethylene glycol （SAN-g-PEG） copolymer was synthesized as new solid-solid phase change materials （SSPCMs） by grafting PEG to the main chain of poly（styrene-co-acrylonitrile）. The chemical structure of the SAN-g-PEG was confirmed by the Fourier transform infrared （FT-IR） and proton nuclear magnetic resonance （1H NMR） spectroscopy techniques. The thermal energy storage properties and the storage durability of the SAN-g-PEG were investigated by differential scanning calorimetry （DSC）. The SAN-g-PEG was endowed with the solid- solid phase transition temperatures within the range of 23-36 ℃ and the latent heat enthalpy ranged from 66.8 kJ/kg to 68.3 kJ/kg. Thermal cycling tests revealed that the SAN-g-PEG kept great heat storage durability after 1000 thermal cycles. The thermal stability was evaluated by a thermal gravity analysis （TGA）, and the initial decomposition temperature （Td） of SAN-g-PEG is 350 ℃, which proves that the SAN-g-PEG possessed good thermal stabilitv.

关键词： Phase change materialEnergy storage and conversionThermal propertiesPolyethylene glycol

Smart Interfacing between Co-Fe Layered Double Hydroxide and Graphitic Carbon Nitride for High-efficiency Electrocatalytic Nitrogen Reduction

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Energy & Environmental Materials 2023年第2期6卷 62-69页

作者： Xiaohui Wu Lu Tang yang si Chunlan Ma Peng Zhang Jianyong Yu Yitao Liu Bin Ding Key Laboratory of High Performance Fibers&Products(Ministry of Education) College of TextilesDonghua UniversityShanghai 201620China Innovation Center for Textile Science and Technology Donghua UniversityShanghai 200051China Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and TechnologySuzhou University of Science and TechnologySuzhou 215009China State Center for International Cooperation on Designer Low-carbon&Environmental Materials(CDLCEM) School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China

Bimetallic compounds such as hydrotalcite-type layered double hydroxides(LDHs)are promising electrocatalysts owing to their unique electronic ***,their abilities toward nitrogen adsorption and reduction are undermined since the surface-mantled,electronegative-OH groups hinder the charge transfer between transition metal atoms and nitrogen ***,a smart interfacing strategy is proposed to construct a coupled heterointerface between LDH and 2D g-C_(3)N_(4),which is proven by density functional theory(DFT)investigations to be favorable for nitrogen adsorption and ammonia desorption compared with neat LDH *** interfaced LDH and g-C_(3)N_(4) is further hybridized with a self-standing TiO_(2) nanofibrous membrane(NM)to maximize the interfacial effect owing to its high porosity and large surface *** from the synergistic superiorities of the three components,the LDH@C_(3)N_(4)@TiO_(2) NM delivers superior ammonia yield(2.07×10^(−9) mol s^(−1) cm^(−2))and Faradaic efficiency(25.3%),making it a high-efficiency,noble-metal-free catalyst system toward electrocatalytic nitrogen reduction.

关键词： density functional theory electrocatalytic nitrogen reduction graphitic carbon nitride interface engineering layered double hydroxide

Semileptonic and nonleptonic decays of B_(u,d,s)^(*) in the covariant light-front approach

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Chinese Physics C 2024年第12期48卷 20-36页

作者： si-yang Wang You-Ya yang Zhi-Jie Sun Hao yang Peng Li Zhi-Qing Zhang Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Institute of Theoretical Physics School of SciencesHenan University of TechnologyZhengzhou 450001China Institute for Complexity Science Henan University of TechnologyZhengzhou 450001China

The semileptonic and nonleptonic decays of the b-flavor vector mesons B_(u,d,s)^(*) and B_(c)^(*) are investigated within the covariant light-front quark model(CLFQM).By calculating the form factors of the transitions B_(u,d,s)^(*)→P under the CLFQM,with P denoting a pseudoscalar meson,i.e.,π,K,η_(c)(1S,2S),D_((s)),B_((s)),we predict and discuss several physical observables,including the branching ratios,polarization fractions f_(L),f_(∥),and forward-backward asymmetries A_(FB).The total widths of the single-photon radiative decay channels for these b-flavor vector mesons are estimated using their partial *** these considered decays,one can find that the semileptonic decays B_(s)_(*0)→D_(s)^(-)l′+ν_(l′)and B_(c)^(*+)→B_(s)^(0)l′+ν_(l′),η_(c)l′+ν_(l′),with l′being e orτ,and the nonleptonic channels B*+c→B0sπ+,B0sρ+have the largest branching ratios,which can reach up to the 10^(-7) order,and are most likely to be accessible at the future high-luminosity LHCb and Belle-II experiments.

关键词： b-flavor vector mesons B^(*) covariant light-front quark model branchig ratio

Microstructure and magnetic properties of Nd-Fe-B sintered magnets with P addition

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Rare Metals 2019年第8期38卷 770-775页

作者： Fang yang Guang-Le Dong Yan-Li Sui si-yang Ye Ping Li Cun-Guang Chen Xue-Xu Gao Zhi-Meng Guo Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083 China Tianjian Sanhuan Lucky New Materials Inc. Tianjin 300457China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083 China

In this paper,the effects of P doping on magnetic properties and microstructure were studied in Nd-Fe-B sintered *** P doping,the grain size gets refined and the distribution of the main phase is optimized due to the reduction of the liquidus *** liquidus temperature for the 0.05 wt% P-doped magnets is 1022 K,while that for the P-free magnets is 1038 *** P content increases,the liquidus temperature significantly *** and continuous grain boundary phases are formed in the P-containing magnets with smaller grain *** optimized microstructure with average grain size of 8.43 μm is obtained in the 0.05 wt% P-doped magnets,which is approximately 0.69 μm smaller than that of P-free sintered magnets (9.12 μm).Though P is usually thought to be an impurity element,it might be beneficial in Nd-Fe-B sintered magnets with proper *** coercivity of the 0.05 wt% P-doped magnets could be increased to 1283 kA·m-1,with slight changes of the remanence and the maximum magnetic energy ***4 phases in the grain boundary are of hexagonal structure,while those at the triple junctions have monoclinic *** sintering is achieved by doping proper P element in the Nd-Fe-B sintered magnets.

关键词： Nd-Fe-B sintered magnets P Microstructure Magnetic properties Activated sintering

The preliminary processing and analysis of LPR Channel-2B data from Chang'E-3

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Science China(Physics,Mechanics & Astronomy) 2014年第12期57卷 2346-2353页

作者： ZHAO Na ZHU Pei Min yang Ke si YUAN Yue Feng GUO Shi Li Institute of Geophysics and Geomatics China University of Geosciences Hubei Subsurface Multi-scale Imaging Lab China University of Geosciences College of Resources and Environmental Sciences Henan Institute of Engineering

The Lunar Penetrating Radar(LPR)carried by Chang’E-3 has imaged the shallow subsurface of the landing site at the northern Mare *** antenna B of the Channel-2 onboard the LPR(LPR Channel-2B)has collected more than 2000 traces of usable raw *** of the low resolution and noise of the raw data,only a few shallow geological structures are *** improve the resolution and the signal-to-noise ratio of the LPR data,we processed the LPR data including amplitude compensation,filtering,and deconvolution *** processing results reveal that the data processing in this study not only improves the signal-to-noise ratio of the LPR Channel-2B data but also makes the geological structures *** processing results will lay the foundation for the subsequent geological interpretation and physical property inversion of lunar materials.

关键词： data processing Lunar Penetrating Radar Chang'E-3 lunar subsurface Moon

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战国楚漆奁的造物范式及文化意蕴探赜

艺术百家 2023年第6期39卷 145-155页

作者：杨先艺杨四宝武汉理工大学艺术与设计学院湖北武汉430070

在数千年中国漆工艺传统文化的演化历程中,文化与器物的互渗现象尤为突出。绚丽多彩的战国漆器是我国悠久的漆器工艺史上的一朵奇葩。楚漆奁作为战国时期日用梳妆器具的承载器物,其形制、纹饰及铭文积淀着深刻的文化内涵。论文寻绎战国... 详细信息

在数千年中国漆工艺传统文化的演化历程中,文化与器物的互渗现象尤为突出。绚丽多彩的战国漆器是我国悠久的漆器工艺史上的一朵奇葩。楚漆奁作为战国时期日用梳妆器具的承载器物,其形制、纹饰及铭文积淀着深刻的文化内涵。论文寻绎战国楚漆奁日用器具的历史,探讨楚漆奁的发生与演化、形态与特征;分析楚式妆奁这一典型的“有意味的造物形式”的造物艺术所反映的文化现象;主要从设计之用、设计之理、设计之法三个层面探索楚漆奁造物艺术的功能之境、审美之境、伦理之境。论文首先采用量化分析法解读楚漆奁形态,获得对楚漆奁相对客观、可靠、科学的数理依据。其次,运用二重证据法研读楚漆奁实物材料与文本,探寻楚漆奁设计之理,即巧循自然资源与法则、巧顺楚人审美情感。最后,从图像学的角度揭示楚漆奁图式的情感表征与生命意识。楚漆奁造物艺术不仅蕴含着大量的风俗与信仰,还展现了楚人特有的巫之玄想、道之壮阔的文化特质和深刻精神内涵。

关键词：楚漆奁造物范式生命符号审美意识自由精神

Structure of a histone hexamer bound by the chaperone domains of SPT16 and MCM2

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Science China(Life Sciences) 2024年第6期67卷 1305-1307页

作者： Songlin Gan Wen-si yang Liting Wei Zhiguo Zhang Rui-Ming Xu Key Laboratory of Epigenetic Regulation and Intervention Institute of BiophysicsChinese Academy of SciencesBeijing 100101China School of Life Sciences University of Chinese Academy of SciencesBeijing 100049China Institute for Cancer Genetics Department of Pediatrics and Department of Genetics and DevelopmentColumbia University Irving Medical CenterNew York 10032USA School of Life Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Dear Editor,The passage of DNA replication forks during eukaryotic cell division disrupts the nucleosomes they encounter,and de novo assembly of nucleosomes onto replicated DNA must take place to restore chromatin ***... 详细信息

关键词： structure nucleosome passage

Optimization of ultrasound-assisted extraction of camptothecin from Camptotheca acuminata seeds

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Journal of Forestry Research 2011年第2期22卷 239-242页

作者： JING Li-jia LI si-yang CHANG Zui WANG yang YAN Xiu-feng Key Laboratory of Saline-alkali Vegetation Ecology Restoration in OilField Ministry of Education Northeast Forestry University 26 Hexingroad Harbin City 150040 Heilongjiang Province P.R. China.

Naturally occurring camptothecin（CPT） is an important source of chemotherapeutic *** extraction from Camptotheca acuminata is still the main approach to obtain CPT compared with total *** the present study,ultrasound-assisted extractions（UAE） of CPT from *** seeds with alkaline solutions were investigated and CPT yield were determined by High Performance Liquid *** conditions of alkaline species and concentrations,extraction time,extraction temperature and ultrasonic power were *** show that both Na3PO4 and Na2CO3 solutions gain good extraction yields,whereas Na3PO4 solution has stronger basicity and need higher concentration than Na2CO3 solution does,thus aqueous Na2CO3 is more beneficial for the *** optimal condition was ultrasonically extracted with 0.5% aqueous Na2CO3 at 50°C and ultrasonic power of 400 W for 60 *** with UAE with ethanol,the extraction with 0.5% Na2CO3 solution achieves higher ***,aqueous Na2CO3 as a solvent has various advantages including non-toxicity,inflammable,non-corrosive and low cost,which ensure this UAE method is a superior method with high utilizing prospect.

关键词： camptothecin Camptotheca acuminata ultrasound-assistant extraction

Regulation of morphology and visible light-driven photocatalysis of WO_(3)nanostructures by changing pH

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Rare Metals 2021年第7期40卷 1738-1745页

作者： You-Shu Fan Xiao-Li Xi yang-si Liu Zuo-Ren Nie Lin-Yan Zhao Qing-Hua Zhang College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China National Engineering Laboratory for Industrial Big-data Application Technology Beijing University of TechnologyBeijing 100124China

The controlled preparation of hexagonal tungsten trioxide(h-WO_(3))nanostructures was achieved by adjusting the pH of the precursor *** effect of the pH on the morphology,elemental composition,and photocatalytic performance of the samples was characterized via X-ray diffraction(XRD),scanning electron microscopy,energy dispersive X-ray spectroscopy,and Raman ***-visible(UV-Vis)spectra were used to evaluate the absorbance and the photocatalytic performance of methylene ***(PL),electrochemical impedance spectroscopy,photocurrent response and Brunauer-Emmett-Teller(BET)were used to study the optical properties,electrical performance,and specific surface area of the WO_(3)-nanostructures,*** results indicate that the WO_(3) nanorods prepared at pH=1.0 exhibit the highest photocatalytic performance(87.4%in 1 h),whereas the WO_(3) nanoblocks prepared at p H=3.0 show the *** photocatalytic performance of the one dimensional(1 D)-nanorods can be attributed to their high specific surface area and charge transfer *** h-WO_(3) nanostructures were synthesized via a simple method and without a capping *** show an excellent photocatalytic performance,which is promising for their application in environment purification.

关键词： h-WO_(3) Morphology pH Photocatalysis Charge transfer Optoelectrical properties