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Journal of Integrative Plant Biology 2010年第9期52卷 782-792页

作者： Yue-yang Xin An-jun deng Guan-Hua Du Jin-Lan Zhang Hai-Lin Qin Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education & Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

The 1H nuclear magnetic resonance （1H NMR） fingerprints of fractionated non-polar and polar extracts （control substance for plant drug [CSPD] A and B） from the roots of 12 specimens of Saposhnikovia divaricata （Turcz.） Schischk were achieved with Fourier Transform （FT）-NMR spectrometer and assigned by comparison to each other and to the 1H NMR spectra of the isolated individual compounds. These fingerprints were found to be uniform in terms of the specificity for the implication of all 12 specimens being systematically of the same origin. The uniformity was further affirmed by high performance liquid chromatography （HPLC）, which also revealed exactly identical specificity for the identified S. divaricata species with the 1H NMR appearances of corresponding CSPD on the part of the composition of characteristic constituents when comparing to corresponding individual compounds. This investigation unambiguously shows that the specific signals from the chemotaxonomically significant compounds of chromones and coumarins in S. divaricata are exhibited distinctively in the composite features of both 1H NMR fingerprints and HPLC profiles. The 1H NMR and HPLC profiles established can successfully be used as reference for the authentication of the origin of S. divaricata species as well as for chemotaxonomic studies.

关键词： Polarity Optical properties individual Provenance Species Hplc

αDecay in extreme laser fields within a deformed Gamow-like model

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Nuclear Science and Techniques 2024年第2期35卷 131-144页

作者： Qiong Xiao jun-Hao Cheng yang-yang Xu You-Tian Zou jun-Gang deng Tong-Pu Yu Department of Physics National University of Defense TechnologyChangsha 410073China College of Science China Three Gorges UniversityYichang 443002China

In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was *** the deformed Gamow-like model, we found that state-of-the-art lasers can cause a slight change in the α decay penetration probability of most nuclei. In addition, we studied the correlation between the rate of change of the α decay penetration probability and angle between the directions of the laser electric field and α particle emission for different nuclei. Based on this correlation, the average effect of extreme laser fields on the half-life of many nuclei with arbitrary α particle emission angles was calculated. The calculations show that the laser suppression and promotion effects on the α decay penetration probability of the nuclei population with completely random α particle-emission directions are not completely *** remainder led to a change in the average penetration probability of the nuclei. Furthermore, the possibility of achieving a higher average rate of change by altering the spatial shape of the laser is explored. We conclude that circularly polarized lasers may be helpful in future experiments to achieve a more significant average rate of change of the α decay half-life of the nuclei population.

关键词： αDecay Deformed Gamow-like model Half-lives Extreme laser field Penetration probability

Metal-Free Synthesis of 2-Aminobenzothiazoles via I2-Catalyzed Tandem Cyclization Reaction of Amines and Carbon Disulfide

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Chinese Journal of Chemistry 2024年第8期42卷 846-852页

作者： Ting Chen Wei Feng Ruitong yang Shanping Chen Guo-jun deng Key Laboratory for Green Organic Synthesis and Application of Hunan Province Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of EducationCollege of ChemistryXiangtan UniversityXiangtanHunan411105 China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHunan453007 China

Comprehensive Summary,A convenient approach for the construction of 2-aminobenzothiazoles via I2-catalyzed tandem cyclization reaction of amines and carbon disulfide has been *** present approach starts from simple and readily available starting materials,affording a series of 2-aminobenzothiazoles in up to 89%yields under metal-free *** this work,C—H/N—H functionalization was achieved and multiple C-hetero bonds were successfully constructed in one pot.

关键词： Sulfur heterocycles C-H functionalization Cyclization Tandem reaction Transition-metal-free Amines lodine N-Heterocycles

Carbon Fiber Breakage Mechanism in Aluminum(Al)/Carbon Fibers(CFs) Composite Sheet during Accumulative Roll Bonding(ARB) Process

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 167-173页

作者：胡淑芬 SUN Zhenzhong SHEN Fanghua deng jun 杨卫平杨浩坤 School of Engineering Jiangxi Agricultural UniversityNanchang 330045China School of Mechanical Engineering Dongguan University of TechnologyDongguan 510730China Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology Dongguan 510730China Smart Manufacturing Division Hong Kong Productivity Council78 Tat Chee AvenueHong Kong 5999075China

We put forward a method of fabricating Aluminum(Al)/carbon fibers(CFs) composite sheets by the accumulative roll bonding(ARB) method. The finished Al/CFs composite sheet has CFs and pure Al sheets as sandwich and surface layers. After cross-section observation of the Al/CFs composite sheet, we found that the CFs discretely distributed within the sandwich layer. Besides, the tensile test showed that the contribution of the sandwich CFs layer to tensile strength was less than 11% compared with annealed pure Al sheet. With ex-situ observation of the CFs breakage evolution with-16%,-32%, and-45% rolling reduction during the ARB process, the plastic instability of the Al layer was found to bring shear damages to the CFs. At last, the bridging strengthening mechanism introduced by CFs was sacrificed. We provide new insight into and instruction on Al/CFs composite sheet preparation method and processing parameters.

关键词： Al/CFs composite sheet accumulative roll bonding tensile strength plastic instability carbon fiber breakage

Lath-like phases formed at an extremely high temperature in a Mg-RE(RE=rare earth)-Al alloy

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Rare Metals 2024年第8期43卷 3937-3945页

作者： Bo deng Shu-Hui Lv Qiang yang Dong-Yue Zhao jun-Yuan Fan Xin Qiu School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Chongqing Research Institute Changchun University of Science and TechnologyChongqing 401135China

Thermal stable intermetallic particles are important for the heat resistance of magnesium(Mg)*** this work,many lath-like particles formed in α-Mg grains of a Mg-8Gd-3Sm-0.7Al casting alloy when heat-treated at 873 ***-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM) characterizations indicate that most of them are Mg-containing Al_(2)(Gd,Sm),with the atomic ratio of Mg:Al:(Gd,Sm) being ~1:1:1;a small part of them with relatively wider thickness are long-period stacking ordered(LPSO) phases simultaneously containing both 14H and 18R *** followed common orientation relationships with Mg matrix as those reported in previous *** addition,many Mg laths were observed in the primary blocky Al_(2)(Gd,Sm) phase at grain boundaries,where the atomic ratio of Al:(Gd,Sm) in the Al_(2)(Gd,Sm) matrix was 2:***,density functional theory(DFT) calculations illustrated the detail structure of the re-constructed Mg/Al_(2)RE interface and simultaneously deduced the underlying reason for the re-dissolution of the newly formed Mg-containing Al_(2)(Gd,Sm) plates in α-Mg matrix.

关键词： Magnesium alloy HAADF-STEM Microstructures Intermetallic particles Orientation relationships Interfaces

Independent control of circularly polarized light with exceptional topological phase coding metasurfaces

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Photonics Research 2024年第6期12卷 534-542页

作者： YICHENG LI SHICHENG WAN SHAOXUAN deng ZHENGWEI deng BO LV CHUNYING GUAN jun yang ANDREY BOGDANOV PAVEL BELOV JINHUI SHI Key Laboratory of Photonic Materials and Devices Physics for Oceanic Applications Ministry of Industry and Information TechnologyCollege of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001China Key Laboratory of In-Fiber Integrated Optics of Ministry of Education College of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001China School of Physics and Engineering ITMO UniversitySt.Petersburg 197101Russia School of Information Engineering Guangdong University of TechnologyGuangzhou 510008China Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China

Exceptional points,as degenerate points of non-Hermitian parity-time symmetric systems,have many unique physical *** to its flexible control of electromagnetic waves,a metasurface is frequently used in the field of *** this work,we developed a parity-time symmetric metasurface and implemented the 2πtopological phase surrounding an exceptional *** with Pancharatnam-Berry phase,the topological phase around an exceptional point can achieve independent regulation of several circular polarization *** combined the Pancharatnam-Berry phase with the exceptional topological phase and proposed a composite coding metasurface to achieve reflection decoupling of different circular *** work provides a design idea for polarimetric coding metasurfaces in the future.

关键词： properties. exceptional topological

Study and application on fire extinguishing and preventing with light-paste material for coalmine

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Journal of Coal Science & Engineering(China) 2011年第3期17卷 340-344页

作者： XIAO yang deng jun LI Shu-gang LIU Xin WU Hui-ping Key Laboratory of Western Mine Exploitation and Hazard Prevention Ministry of Education College of Energy Science ＆ Engineering Xi＇an University of Science and Technology Xi＇an 710054 China

For preventing and extinguishing the spontaneous combustion of coal seam, based on the importance for sealing air leakage channels in roadway, developed a material of light-paste for coalmine, and research its ingredient, proportion and performance. The result indicates that the component ratio of the material is which PB exciting agent is 20%, complex reinforcing agent is 2%, complex expansion agent is 1%, and A-material is 77%. The performances of compressive strength, swelling ratio and expansion time are optimum. The light-paste material can effectively seal air leakage channels for preventing and extinguishing the spontaneous combustion of coal seam in coalmine.

关键词： light-paste exciting agent reinforcing agent swelling ratio expansion time

Effect of nano-graphite on mechanical properties and oxidation resistance of ZrB_(2)-SiC-graphite electrode ceramics

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Journal of Iron and Steel Research International 2024年第6期31卷 1502-1513页

作者： Bo-lin yang Chang-liu Kuang Zheng-long Liu Chao Yu Cheng-ji deng jun Ding The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrB_(2)-based ceramic composites were prepared by spark plasma sintering using ZrB_(2) powder prepared by molten salt method as raw material and SiC and nano-graphite as *** effects of nano-graphite addition on the physical properties and oxidation resistance of ZrB_(2)-based ceramic samples were *** results show that the addition of an appropriate amount of nano-graphite can effectively improve the density of ZrB_(2)-based ceramic composites and improve the physical properties of the *** flexural strength of the ceramic sample with 8 vol.%nano-graphite reached 418.54 MPa,which was 53.14% higher than that of ZrB_(2)-SiC ceramic material(273.31 MPa),and its oxidation resistance was also significantly *** demonstrats that the addition of an appropriate amount of nano-graphite can effectively improve the physical properties and oxidation resistance of ZrB_(2)-SiC ceramic *** prolonging its service life in application and promoting the development of ZrB_(2)-based ceramic composites,it is of great significance for clean steel smelting.

关键词： ZrB_(2)-SiC-graphite electrode ceramic ZrB_(2)-based ceramic composite Nano-graphite Physical property Oxidation resistance

Superhydrophobic Surface-Assisted Preparation of Microspheres and Supraparticles and Their Applications

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Nano-Micro Letters 2024年第4期16卷 110-138页

作者： Mengyao Pan Huijuan Shao Yue Fan Jinlong yang Jiaxin Liu Zhongqian deng Zhenda Liu Zhidi Chen jun Zhang Kangfeng Yi Yucai Su Dehui Wang Xu deng Fei deng Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 611731People’s Republic of China School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275People’s Republic of China Shenzhen Institute for Advanced Study University of Electronic Science and Technology of ChinaShenzhen 518110People’s Republic of China Pharmaceutical Glass Co.Ltd Zibo 256100People’s Republic of China Department of Nephropathy School of MedicineSichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduPeople’s Republic of China Department of Nephrology Sichuan Provincial People’s Hospital Jinniu HospitalChengdu Jinniu District People’s HospitalChengduPeople’s Republic of China

Superhydrophobic surface(SHS) has been well developed, as SHS renders the property of minimizing the water/solid contact interface. Water droplets deposited onto SHS with contact angles exceeding 150°, allow them to retain spherical shapes, and the low adhesion of SHS facilitates easy droplet collection when tilting the substrate. These characteristics make SHS suitable for a wide range of applications. One particularly promising application is the fabrication of microsphere and supraparticle materials. SHS offers a distinct advantage as a universal platform capable of providing customized services for a variety of microspheres and supraparticles. In this review, an overview of the strategies for fabricating microspheres and supraparticles with the aid of SHS, including cross-linking process, polymer melting,and droplet template evaporation methods, is first presented. Then, the applications of microspheres and supraparticles formed onto SHS are discussed in detail, for example, fabricating photonic devices with controllable structures and tunable structural colors, acting as catalysts with emerging or synergetic properties, being integrated into the biomedical field to construct the devices with different medicinal purposes, being utilized for inducing protein crystallization and detecting trace amounts of analytes. Finally,the perspective on future developments involved with this research field is given, along with some obstacles and opportunities.

关键词： Superhydrophobic surface Microspheres and supraparticles Photonic devices Catalysts Biomedical and trace detections

A New Heat Transfer Model for Multi-Gradient Drilling with Hollow Sphere Injection

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Fluid Dynamics & Materials Processing 2024年第3期20卷 537-546页

作者： Jiangshuai Wang Chuchu Cai Pan Fu jun Li Hongwei yang Song deng School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhouChina CNPC Research Institute of Engineering Technology Co. Ltd.BeijingChina National Engineering Research Center for Oil&Gas Drilling and Completion Technology BeijingChina College of Petroleum Engineering China University of Petroleum(Beijing)BeijingChina College of Petroleum Karamay CampusChina University of Petroleum(Beijing)BeijingChina

Multi-gradient drilling is a new offshore drilling *** accurate calculation of the related wellbore temperature is of great significance for the prediction of the gas hydrate formation area and the precise control of the wellbore *** this study,a new heat transfer model is proposed by which the variable mass flow is properly taken into *** this model,the effects of the main factors influencing the wellbore temperature are *** results indicate that at the position where the separation injection device is installed,the temperature increase of the fluid in the drill pipe is mitigated due to the inflow/outflow of hollow spheres,and the temperature drop of the fluid in the annulus also *** addition,a lower separation efficiency of the device,a shallower installation depth and a smaller circulating displacement tend to increase the temperature near the bottom of the annulus,thereby helping to reduce the hydrate generation area and playing a positive role in the prevention and control of hydrates in deepwater drilling.

关键词： Multi-gradient drilling wellbore temperature hydrate separate injection device variable mass