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CSS J075415.6+191052 and NW Leo: Two Contact Binaries at Different Evolutionary Stages

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Research in Astronomy and Astrophysics 2022年第2期22卷 118-127页

作者： Xu-Dong Zhang Sheng-Bang Qian Er-Gang Zhao Qi-jun Zhi ai-jun Dong Bin Zhang School of Physics and Electronic Science Guizhou Normal University550025 GuiyangChina Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025 GuiyangChina Yunnan Observatories Chinese Academy of Sciences(CAS)650216 KunmingChina University of Chinese Academy of Sciences(UCAS) 100049 BeijingChina

Multi-color light curves of CSS J075415.6+191052 and NW Leo are presented and the photometric solutions suggest that CSS J075415.6+191052 is an A-subtype contact binary with low mass ratio(q = 0.178) while NW Leo has a high mass ratio(q = 0.707). For CSS J075415.6+191052, the RI light curves show weakening around the left shoulder of the secondary minimum, which indicates that there may be a dark spot on the secondary component. However, the light curves of BV bands are totally symmetric. It is unreasonable if the dark spot is caused by magnetic activity or mass transfer between the two components. Therefore, weakening of the light curves in this contact binary is caused by something else. A possible explanation is mass transferring from the primary component to the common convective envelope through the inner Lagrangian point, and this part of the mass, for some reason, weakens the RI bands of light from the secondary component. O-C analysis of NW Leo reveals a cyclic period change with a modulation period of 4.7 yr, which may be caused by the light travel time effect of a third body. The positions of CSS J075415.6+191052 and NW Leo in the P–J′_(orb)diagram indicate that CSS J075415.6+191052 mainly abides by the angular momentum loss theory while NW Leo is dominated by the thermal relaxation oscillation theory.

关键词： (stars:)binaries:eclipsing stars:evolution stars:individual(CSS J075415.6+191052 NW Leo)

Promoting electrocatalytic nitrogen reduction to ammonia via dopant boron on two-dimensional materials

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Rare Metals 2024年第10期43卷 5117-5125页

作者： Ya-Hui Cui Wen-Cheng Ouyang ai-jun Gao Chang-Yuan Yu Li-Peng Zhang State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China College of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China

Electrocatalytic nitrogen reduction reaction(NRR)is a key process for producing energy efficient and environment friendly ***-doped two-dimensional materials are highly promising as NRR ***,the interaction between doped boron and matrix materials on NRR catalytic performance is still unclear,which is limiting the development of catalysts containing boron for ***,NRR on different boron-doped twodimensional(2D)materials was explored by first principle *** is found that adsorption energy of intermediate*NNH(E*NNH)can be used as a descriptor to characterize the catalytic activity for ***-adsorbed black phosphorus(B-BP)is demonstrated showing excellent NRR catalytic activity and suppressing hydrogen evolution *** is disclosed that the excellent catalytic performance of boron-doped structures comes from a proper quantitatively electron transfer(0.8e)between nitrogen in*NNH and the active site boron *** work not only established a descriptor for NRR catalytic activity on B-doped 2D materials,but also screened out a potential NRR *** importantly,the intrinsic reason and mechanism of high catalytic activity of boron-doped structures were *** work provides a design principle for exploring high-performance NRR electrocatalysts containing boron.

关键词： Electrocatalytic nitrogen reduction reaction Boron-doped two-dimensional materials Descriptor Density functional theory

Chemical characterization of smoke from the production process of wood-plastic composites

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Forestry Studies in China 2007年第1期9卷 57-62页

作者： Wang Shi-fa Zhang ai-jun College of Chemical Engineering Nanjing Forestry University Nanjing 210037 P. R. China Department of Entomology Virginia Polytechnic Institute and State University Blacksburg VA 24061 USA Chemicals Affecting Insect Behavior Laboratory Beltsville Agriculture Research Center-West USDA Agriculture Research Services Beltsville MD 20705 USA

The chemical composition of unpleasant smell, emitted from the production process of wood-plastic composites using Manchurian ash sawdust （Fraxinus mandschurica Rupr.） and polypropylene powder as the raw material, was investigated. Wood sawdust and polypropylene powder were subjected to heat treatment to 290℃ during 8 min （the conditions were similar to those employed on an industrial scale）. The emitted compounds were collected and analyzed by gas chromatography-mass spectrometry （GC-MS）. The analytical results showed that the unpleasant smell was emitted from the pyrogenation of wood sawdust rather than from the polypropylene powder. Nine types of compounds （hydrocarbons, ethers, phenols, aldehydes, ketones, alcohols, acids and their derivatives, furan and its derivatives, and nitrogen-containing compounds） were collected in the gas phase during heating. Among those 126 components detected by GC-MS, 112 compounds were identified.

关键词： wood-plastic composite unpleasant smell pyrogenation Manchurian ash sawdust polypropylene powder

Progress in ion detection and clinical diagnosis based on G-quadruplex combined with fluorescence properties

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Advanced Sensor and Energy Materials

Advanced Sensor and Energy Materials 2024年第3期3卷 61-70页

作者： Ping Lu Gerile Aodeng jun ai College of Chemistry and Environmental Science Inner Mongolia Key Laboratory of Environmental ChemistryInner Mongolia Normal UniversityHohhot 010022China

G-quadruplex is a high-level structure composed of folded DNA or RNA rich in tandem repeats of guanine(G).In recent years,G-quadruplex is widely used in various fields due to its unique structural *** article briefly introduces the structural properties of G-quadruplex,and provides a brief introduction to the research on DNA and RNA G-quadruplex in various detection and medical *** is hoped that this can provide some help to readers who want to understand G-quadruplex.

关键词： G-quadruplex DNA G-quadruplex RNA G-quadruplex Detection Medical

Spray-coated SnO_(2) electron transport layer with high uniformity for planar perovskite solar cells

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 180-186页

作者： Yaqin Wang Lin Yang Chunxiang Dall’Agnese Gang Chen ai-jun Li Xiao-Feng Wang Key Laboratory of Physics and Technology for Advanced Batteries(Ministry of Education) College of PhysicsJilin UniversityChangchun 130012China College of Physics Jilin UniversityChangchun 130012China

SnO_(2) has been proven to be an effective electron transport layer(ETL)material for perovskite solar cells(PSCs)owing to its excellent electrical and optical ***,we introduce a viable spray coating method for the preparation of SnO2 ***,we employ a SnO_(2) film prepared using the spray coating method as an ETL for *** PSC based on the spray-coated SnO_(2) ETL achieves a power conversion efficiency of 17.78%,which is comparable to that of PSCs based on conventional spin-coated SnO_(2) *** large-area SnO_(2) films prepared by spray coating exhibit good repeatability for device *** study shows that SnO_(2) films prepared by spray coating can be applied as ETLs for stable and high-efficiency *** the proposed method involves low material consumption,it enables the low-cost and large-scale production of PSCs.

关键词： spray coating SnO_(2)film ETL PSCs

Al-modified yolk-shell silica particle-supported NiMo catalysts for ultradeep hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene:Efficient accessibility of active sites and suitable acidity

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Petroleum Science 2024年第1期21卷 654-666页

作者： Ke Yu Wei-Min Kong Zhen Zhao ai-jun Duan Lian Kong Xi-Long Wang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034LiaoningChina

Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective ***-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proportion)were prepared and dibenzothiophene(DBT)and 4,6-dimethyl-dibenzothiophene(4,6-DMDBT)were employed as the probes to evaluate the hydrodesulfurization(HDS)catalytic *** as-prepared AYP-x carriers and corresponding catalysts were characterized by some advanced characterizations to obtain deeper correlations between physicochemical properties and the HDS *** average pore sizes of series AYP-x supports are above 6.0 nm,which favors the mass transfer of organic *** cavity between the yolk and the shell is beneficial for the enrichment of S-containing compounds and the accessibility between reactants and active *** embedded into the silica framework could facilitate the formation of Lewis(L)and Brønsted(B)acid sites and adjust the metal-support interaction(MSI).Among all the as-synthesized catalysts,NiMo/AYP-20 catalyst shows the highest HDS *** improved HDS activity of NiMo/AYP-20 catalyst is attributed to the perfect combination of excellent structural properties of the yolk-shell mesoporous silica,enhanced acidity,moderate MSI,and good accessibility/dispersion of active components.

关键词： Al-containing yolk-shell silica particles Accessibility Acidity Metal-support interaction Hydrodesulfurization

Perovskite fluoride NaNiF_(3) with hollow micron sphere structure as anode for Li-ion hybrid capacitors

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Rare Metals 2022年第10期41卷 3370-3380页

作者： ai-jun Jiao Jian-Fei Gao Zheng-Hua He Jing-Feng Hou Ling-Bin Kong State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of TechnologyLanzhou730050China

Lithium-ion hybrid capacitors(LIHCs) are gaining more attention and applications because they break the performance limitations of supercapacitors(SCs) and lithium-ion batteries(LIBs).However,the difference of energy storage mechanism between anode and cathode is a problem that must be faced by Li-ion hybrid *** selection of suitable anode and cathode materials is one of the effective ways to solve this ***,we synthesized hollow spherical perovskite fluoride NaNiF3 by a simple and safe *** specific capacity of NaNiF3 is 142 mAh·g^(-1) at 0.1 A·g^(-1) for 1000 *** mechanism in the cycling of NaNiF3 electrodes was investigated using ex situ X-ray photoelectron spectroscopy(XPS),which is typical of the conversion ***,the NaNiF_(3)//activated carbon(AC) Li-ion hybrid capacitor assembled and showed better energy density(69 Wh·kg^(-1)) and power density(5699 W·kg^(-1)).Its capacity retention after long cycling was 79%.The use of NaNiF3 expands the choice of electrode materials for LIHCs and extends their practical applications.

关键词： Perovskite fluoride Anode Conversion mechanism Li-ion hybrid capacitor

Bulk Metallic Glasses: MRI Compatibility and Its Correlation with Magnetic Susceptibility

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Journal of Materials Science & Technology 2016年第6期32卷 496-504页

作者： Da-Bo Zhou Shao-Ping Wang Shao-Gang Wang Hong-jun ai Jian Xu School of Stomatology China Medical University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

Several bulk metallic glasses （BMGs） were selected to in vitro assess their magnetic resonance imaging （MRI） compatibility with agarose gel as a phantom, in terms of the extent of susceptibility artifacts in magnetic resonance image. The investigated metals include the ***2.3Cu26.9Si16.3, Zr61Ti2Cu2sA112, Cu50.4Nis.0Ti31Zr13 and Ti47Cu38Zr7.5Fe2.5Sn2Si1Ag2, together with pure titanium （CP-Ti） and Co-28Cr-6Mo alloy （ASTM-F799） for comparison. The artifact extent in MR images was quantitatively characterized according to the total volume in reconstructed 3D images with a series of slices under acquisition by fast spin echo （FSE） sequence and gradient echo （GRE） sequence. As indicated, artifact severity of the BMGs is much less than that of the CoCrMo alloy. The AuAgPdCuSi BMG manifested the smallest arti- fact among the four BMGs, while the TiCuZrFeSnSiAg BMG is comparative to the CP-Ti. The MRI compatibility of BMGs is ranked as a sequence of the Au-, Zr-, Cu- and Ti-based alloys. Dependence of material mag- netic susceptibility on artifact extent is also the case of the BMGs, even though it does not follow a simple linear relationship within a range of △χv = 30-180 ppm. These findings are of interest to reveal that the BMGs are potentially applied in the fields associated with an interventional MRI for MRI-guided surgeries.

关键词： Metallic glass MRI compatibility Magnetic susceptibility Metal-induced artifacts Biomaterials

质量管理小组标准化活动在电力标签发行质量提升中的应用

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中国标准化 2025年第1期 199-204,210页

作者：夏立佳平爱军许振华北京智芯微电子科技有限公司

以电力柔性RFID电子标签发行质量提升为例,充分发挥质量管理小组的作用,在成立质量管理小组后,依据质量管理小组创新型活动程序,通过选择课题、设定目标及目标可行性论证、提出方案并确定最佳方案、制定对策、对策实施、效果检查、标准... 详细信息

以电力柔性RFID电子标签发行质量提升为例,充分发挥质量管理小组的作用,在成立质量管理小组后,依据质量管理小组创新型活动程序,通过选择课题、设定目标及目标可行性论证、提出方案并确定最佳方案、制定对策、对策实施、效果检查、标准化、总结和下一步打算共计八个步骤,对项目需求进行系统研究论证,在项目执行过程中进行应用,达到了产品质量提升的目的。本文采用的标准化活动流程,对其他项目的研究、论证、实施具有重要的指导作用,可以采用质量管理小组标准化活动的方式对重要技术研发和实施难点开展攻克。

关键词：质量管理小组标准化活动电力标签发行质量提升

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