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Preparation and Properties of Pyrotechnic Binder Encapsulated α-AlH3 Composites by Solvent/Anti-solvent Method

CHEMNANOMAT 2023年第5期9卷

作者： Shi, Zhe Lu, Taojie Hu, Yinghui Xu, Yidong Wang, xuwen wu, Zhuo Zheng, Jian Zhang, Jian Zhu, Zhaoyang Lin, Kaifeng Yang, Yulin Harbin Inst Technol Sch Chem & Chem Engn MIIT Key Lab Crit Mat Technol New Energy Convers & Harbin 150001 Peoples R China Hubei Inst Aerosp Chemotechnol Sci & Technol Aerosp Chem Power Lab Xiangyang 441003 Hubei Peoples R China China Aerosp Sci & Technol Corp 16 Fucheng Rd Beijing 100048 Peoples R China

Alpha-aluminum hydride (a-AlH3) is an ideal energetic combustion agent, but its poor stability and safety limit its application. Therefore, we prepare different composites by using the solvent/anti-solvent method to coat different pyrotechnic binders on the surface of a-AlH3. The vacuum stability test show that the minimum outgassing of Shellac-coated a-AlH3 composite is only 1.2 mL/g at 50 ? for 6 days. Due to the good electrical insulation properties of Viton, Viton-coated a-AlH3 composite have the highest E-50 value of electrostatic sensitivity. In addition, the pyrotechnic binders coating not only protects the activity of the a-AlH3 but also effectively increases its burning rate. Viton-coated a-AlH3 composite have more gaseous products and maximum flame area during combustion. This study illustrates that a-AlH3 coated with pyrotechnic binders is a means to address its stability and safety, laying the foundation for its application in solid propellants.

关键词： Pyrotechnic binder alpha-AlH3 Stability Safety Solid propellant

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利用粗糙集和支持向量机的银行借贷风险预测模型

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成都理工大学学报（自然科学版） 2022年第2期49卷 249-256页

作者：吴尚智王旭文王志宁任艺璇西北师范大学计算机科学与工程学院兰州730070

将粗糙集和支持向量机相结合,提出利用粗糙集和支持向量机的银行借贷风险预测模型,提高银行个人借贷风险预测精度,为银行判断是否同意借贷提供参考和依据。该模型首先将银行样本数据形成初始决策表,对其进行数据预处理;然后用属性相似... 详细信息

将粗糙集和支持向量机相结合,提出利用粗糙集和支持向量机的银行借贷风险预测模型,提高银行个人借贷风险预测精度,为银行判断是否同意借贷提供参考和依据。该模型首先将银行样本数据形成初始决策表,对其进行数据预处理;然后用属性相似度的属性约简算法对决策表进行属性约简,去除冗余属性,获得高效的决策规则;最后将约简后的最小属性作为4种不同核函数的支持向量机学习样本,构建预测模型且进行预测评价对比分析。实验结果表明,使用相同训练样本,高斯核函数的支持向量机预测模型的准确率最高且为93%,说明该预测模型具有较高的精度。通过实验分析,构建预测模型有效地预测了银行借贷风险,且为银行借贷管理提供辅助决策。

关键词：粗糙集属性约简支持向量机核函数预测模型

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应用于石墨烯MEMS高温压力传感器的气密封装研究

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电子元件与材料 2022年第5期41卷 508-513页

作者：陈绪文王俊强吴天金中北大学仪器与电子学院山西太原030051 中北大学前沿交叉学科研究院山西太原030051

针对石墨烯MEMS高温压力传感器的高气密要求,设计了一种压膜结构压力传感器,并利用Au-Au键合完成压力传感器的封装。键合前,样品表面采用Ar等离子体预处理,随后在N_(2)氛围下,利用倒装焊机在1.6 kN压力、300℃温度下键合30 min完成键合... 详细信息

针对石墨烯MEMS高温压力传感器的高气密要求,设计了一种压膜结构压力传感器,并利用Au-Au键合完成压力传感器的封装。键合前,样品表面采用Ar等离子体预处理,随后在N_(2)氛围下,利用倒装焊机在1.6 kN压力、300℃温度下键合30 min完成键合工艺。对键合指标进行表征测试,发现器件的最小剪切强度为10.87 MPa,最大泄漏率为9.88×10^(-4) Pa·cm^(3)/s,均满足GJB 548B-2005的要求。在300℃下高温存储(HTS)10 h后,器件的平均剪切强度和泄漏率变化不大,通过传感器压力静态测试发现石墨烯器件在0~60 MPa压力量程内具备高重复性,证明石墨烯在键合过程和高温存储实验后没有变性。实验结果表明Au-Au键合可以完成石墨烯MEMS高温压力传感器高气密封装。

关键词：石墨烯 Au-Au键合高气密封装 MEMS高温压力传感器

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THE DERIVATION OF THE COMPRESSIBLE EULER EQUATION FROM QUANTUM MANY-BODY DYNAMICS

arXiv

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arXiv 2021年

作者： Chen, xuwen Shen, Shunlin wu, Jiahao Zhang, Zhifei Department of Mathematics University of Rochester RochesterNY14627 United States School of Mathematical Sciences Peking University Beijing100871 China

We study the three dimensional many-particle quantum dynamics in mean-field setting. We forge together the hierarchy method and the modulated energy method. We prove rigorously that the compressible Euler equation is the limit as the particle number tends to infinity and the Planck's constant tends to zero. We establish strong and quantitative microscopic to macroscopic convergence of mass and momentum densities up to the 1st blow up time of the limiting Euler equation. We justify that the macroscopic pressure emerges from the space-time averages of microscopic interactions, which are in fact, Strichartz-type bounds. We have hence found a physical meaning for Strichartz type bounds which were first raised by Klainerman and Machedon in this context. Copyright © 2021, The Authors. All rights reserved.

关键词： Euler equations

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Efficient advanced treatment of coking wastewater using O3/H2O2/Fe-shavings process

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JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING 2022年第2期10卷

作者： Yuan, Run Xia, Yu wu, Xu He, Can Qin, Yihe He, Changjun Zhang, Xuewei Li, Na He, xuwen China Univ Min & Technol Beijing Dept Chem & Environm Engn Beijing 100083 Peoples R China Beijing Acad Sci & Technol Inst Resources & Environm Beijing 100089 Peoples R China

Catalytic oxidation is widely used in the treatment of refractory wastewater. However, catalytic oxidation has some problems such as high cost and limited production of radicals. To improve these, in this study, a new process of O-3/H2O2/Fe-shavings which coupled catalytic ozonation and Fenton-like oxidation with Fe-shaving wastes reused, was used in the treatment of coking wastewater secondary biochemical effluent (CWSBE). The effects of the environmental conditions on the degradation of CWSBE were studied and the response surface method was used to optimise the parameters. The performances in organic pollutant removal from CWSBE were systematically analysed by a couple of methods such as gas chromatography mass spectrometry and threedimensional fluorescence. The results showed that macromolecular organics were degraded into small molecules pollutants after treatment by the O-3/H2O2/Fe-shavings process. At an ozone concentration of 27.5 mg/L, with the hydrogen peroxide concentration being 10.7 mmol/L, the reaction time 60 min, the initial pH value 3.6, and the pump speed 150 rpm, the COD removal degradation efficiency was 77.5%, and the effluent COD met relevant wastewater discharge standards in China (GB 16171-2012). The mechanism research showed *** plays an important role in the degradation of organic pollutants.

关键词： Advanced oxidation Coking wastewater Response surface method Water quality analysis Degradation mechanism

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Combining ¹H-NMR-based metabonomics and network pharmacology to dissect the mechanism of antidepression effect of Milletia speciosa Champ on mouse with chronic unpredictable mild stress-induced depression

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JOURNAL OF PHARMACY AND PHARMACOLOGY 2021年第7期73卷 881-892页

作者： Su, Zhiheng Ruan, Junxiang Liu, Xi Zheng, Hua Ruan, Jingzhou Lu, Yuying Cheng, Bang wu, Fang wu, Jinxia Liu, xuwen Song, Fangming Chen, Zhaoni Song, Hui Liang, Yonghong Guo, Hongwei Guangxi Med Univ Pharmaceut Coll Nanning 530021 Peoples R China Guangxi Yuhualing Technol Dev Co LTD Nanning Peoples R China Guangxi Med Univ Life Sci Inst Nanning Peoples R China Peoples Hosp Guangxi Zhuang Autonomous Reg Dept Pharm Nanning Peoples R China

Objectives Milletia speciosa Champ (MS), a traditional Chinese medicine, has the abilities of antistress, antifatigue, anti-oxidation and so on. In our previous study, MS was found to antidepression while the underlying mechanism of which needs further elucidation. Methods Here, a proton nuclear magnetic resonance (H-1-NMR)-based metabonomics combined network pharmacology research approach was performed to investigate the antidepressive mechanism of MS act on mouse with chronic unpredictable mild stress-induced depression. Key findings Results showed that MS could alleviate the ethology of depression (including sucrose preference degree, crossing lattice numbers and stand-up times) and disordered biochemical parameters (5-hydroxytryptamine, norepinephrine and brain-derived neurotrophic factor). Metabonomics study and network pharmacology analysis showed that MS might improve depression through synergistically regulating five targets including Maoa, Maob, Ache, Ido1 and Comt, and three metabolic pathways such as tryptophan metabolism, synthesis of neurotransmitter and phospholipid metabolism. Conclusions This study for the first time preliminary clarified the potential antidepressive mechanism of MS and provided theoretical basis for developing MS into novel effective antidepressant.

关键词： metabonomics H-1-NMR network pharmacology depression chronic unpredictable mild stress Milletia speciosa Champ

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Chemical compositions of mussels and clams from the Tangyin and Yonaguni Knoll IV hydrothermal fields in the southwestern Okinawa Trough

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ORE GEOLOGY REVIEWS 2017年 87卷 172-191页

作者： Zeng, Zhigang Chen, Shuai Ma, Yao Yin, Xuebo Wang, Xiaoyuan Zhang, Suping Zhang, Junlong wu, xuwen Li, Yang Dong, Dong Xiao, Ning Chinese Acad Sci Inst Oceanol Key Lab Marine Geol & Environm Seafloor Hydrothermal Act Lab 7 Nanhai Rd Qingdao 266071 Peoples R China Qingdao Natl Lab Marine Sci & Technol Lab Marine Mineral Resources Qingdao 266071 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Qingdao Collaborat Innovat Ctr Marine Sci & Techn Qingdao 266061 Peoples R China Chinese Acad Sci Inst Oceanol Marine Biol Museum Qingdao 266071 Peoples R China

Studies of the chemical characteristics of mussels and clams in seafloor hydrothermal fields are important for understanding mass fluxes and elemental partitioning from hydrothermal vents into the biosphere, metal bioaccumulation of seafloor hydrothermal ecosystems, and the sources and sinks of biogeochemical and fluid cycles. We are the first to measure the mineral, major, trace and rare earth element, and carbon and oxygen isotope compositions of mussels (Bathymodiolus platifrons) and clams (Conchocele bisecta) from the Tangyin and Yonaguni Knoll IV hydrothermal fields in the southwestern Okinawa Trough. Mineralogical analysis shows that the carbonate shells of the mussel and clam samples are mainly composed of calcite and aragonite. Metal elements exhibit linear correlations in the shells (e.g., V and U) and tissues (e.g., Li and Rb) of the mussels and clams, suggesting that not all positive correlations of elements in tissues are inherited by the shells. V/As, Ca/Sr, and Fe/Cr ratios in the mussels and clams are close to those in the seawater, indicating that element ratios of seawater might be inherited by the mussels and clams. In addition, the Fe/Cr ratio of the shells of both mussels and clams can be used to trace the local seawater composition. The total LREE concentrations of mussel and clam tissue samples are higher than those of the mussel and clam shell samples, are similar to the hydrothermal fluids, exhibit LREE enrichment (La-CN/Nd-CN ratios = 1.86-32.1), and no or only slightly negative Eu anomalies, indicating that benthic animals are a sink of LREEs from hydrothermal fluids, and that the Eu/Eu* ratios of fluids change when fluids are incorporated into the tissues of the mussels and clams. In addition, the delta C-13 values of mussel shell samples are heavier than those of the clam shell samples in the hydrothermal field, indicating that more than one carbon source may be involved in defining the delta C-13 compositions of the shells. The majority

关键词： Mussel Clam C hemical composition Tangyin and Yonaguni Knoll IV hydrothermal fields

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Biochemical and structural characterization of the first-discovered metazoan DNA cytosine-N4 methyltransferase from the bdelloid rotifer Adineta vaga

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JOURNAL OF BIOLOGICAL CHEMISTRY 2023年第8期299卷 105017页

作者： Zhou, Jujun Horton, John R. Kaur, Gundeep Chen, Qin Li, xuwen Mendoza, Fabian wu, Tao Blumenthal, Robert M. Zhang, Xing Cheng, Xiaodong Univ Texas MD Anderson Canc Ctr Dept Epigenet & Mol Carcinogenesis Houston TX 77030 USA Baylor Coll Med Dept Mol & Human Genet Houston TX USA Univ Toledo Coll Med & Life Sci Dept Med Microbiol & Immunol Program Bioinformat Toledo OH 43614 USA

Much is known about the generation, removal, and roles of 5-methylcytosine (5mC) in eukaryote DNA, and there is a growing body of evidence regarding N6-methyladenine, but very little is known about N4-methylcytosine (4mC) in the DNA of eukaryotes. The gene for the first metazoan DNA methyltransferase generating 4mC (N4CMT) was reported and characterized recently by others, in tiny freshwater invertebrates called bdelloid rotifers. Bdelloid rotifers are ancient, apparently asexual animals, and lack canonical 5mC DNA methyltransferases. Here, we characterize the kinetic properties and structural features of the catalytic domain of the N4CMT protein from the bdelloid rotifer Adineta vaga. We find that N4CMT generates high-level methylation at preferred sites, (A/C)CG(T/C/A), and low-level methylation at disfavored sites, exemplified by ACGG. Like the mammalian de novo 5mC DNA methyltransferase 3A/3B (DNMT3A/3B), N4CMT methylates CpG dinucleotides on both DNA strands, generating hemimethylated intermediates and eventually fully methylated CpG sites, particularly in the context of favored symmetric sites. In addition, like DNMT3A/3B, N4CMT methylates non-CpG sites, mainly CpA/TpG, though at a lower rate. Both N4CMT and DNMT3A/3B even prefer similar CpGflanking sequences. Structurally, the catalytic domain of N4CMT closely resembles the Caulobacter crescentus cell cycle-regulated DNA methyltransferase. The symmetric methylation of CpG, and similarity to a cell cycle-regulated DNA methyltransferase, together suggest that N4CMT might also carry out DNA synthesis-dependent methylation following DNA replication.

关键词： DNA methylation N4-methylcytosine metazoan cytosine-N4 DNA methyltransferase bdelloid rotifer Adineta vaga

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焦化废水深度处理新技术及其相互耦合特征研究

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煤炭科学技术 2021年第1期49卷 175-182页

作者：何绪文员润吴姁夏瑜何灿中国矿业大学(北京)化学与环境工程学院北京100083 北京水梦源水务科技有限公司北京100019

焦化废水具有水量大、难降解、水质复杂和处理成本高等特点,且随着"两山论"、"零排放"和GB 16171—2012《炼焦化学工业污染物排放标准》等新理念、新标准的提出,传统深度处理技术已难以使焦化废水处理达标;为了使... 详细信息

焦化废水具有水量大、难降解、水质复杂和处理成本高等特点,且随着"两山论"、"零排放"和GB 16171—2012《炼焦化学工业污染物排放标准》等新理念、新标准的提出,传统深度处理技术已难以使焦化废水处理达标;为了使焦化废水稳定达标排放,探讨了以非均相臭氧催化氧化技术、磁混凝技术和聚瓷膜分离技术为核心的单元深度处理新技术及其相互耦合深度处理新技术;分析了新型臭氧催化剂和新型臭氧反应设备、新型重介质、新型膜材料和新型膜结构分别作为非均相臭氧催化氧化技术、磁混凝技术和聚瓷膜分离技术的重要特征;介绍了3种单元新型深度处理技术及其分别耦合技术的应用现状,并指出耦合新型处理技术可以使焦化废水处理后稳定达到废水排放标准或废水回用标准,总结了不同技术的绿色环保、处理成本低、矿化程度高、处理效果好、短流程和运行稳定等技术优势。根据单元深度处理新技术及其分别耦合新技术的特点,形成了完善和成熟的集成技术工艺包,这将是今后焦化废水深度处理新技术发展的新趋势。

关键词：焦化废水深度处理臭氧催化磁混凝聚瓷膜

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掘进机循环负压降尘装置参数优化研究

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矿业科学学报 2025年第2期10卷 271-284页

作者：邢旭文何少杰田园肖鹏武琨琪张英华张金宝滕胜杰庆阳新庄煤业有限公司新庄煤矿甘肃庆阳745000 北京科技大学资源与安全工程学院北京100083

有效开展掘进巷道工作面粉尘治理是确保井下作业安全的重要前提之一。针对高浓度粉尘环境中传统的喷雾降尘方式效率相对低下的问题,根据负压卷吸与喷雾降尘协同增效的理念研发一种应用于掘进机上的循环负压降尘装置。通过建立仿真模型... 详细信息

有效开展掘进巷道工作面粉尘治理是确保井下作业安全的重要前提之一。针对高浓度粉尘环境中传统的喷雾降尘方式效率相对低下的问题,根据负压卷吸与喷雾降尘协同增效的理念研发一种应用于掘进机上的循环负压降尘装置。通过建立仿真模型对射流卷吸机制的影响因素开展数值模拟,基于装置内外循环负压流场变化规律优化引射管形状、叶轮设置、文丘里管数量等参数,并采用相似实验的方式验证优化后装置的降尘效率。结果表明:在假设喷雾条件不变的情况下,当装置的引射管形状采用圆锥形、叶轮片数量为8片、叶轮转速为2400 r/min、文丘里管数量为10个、叶轮安装位置距引射管入口300 mm时,循环负压性能最为理想,其相似模型的降尘效率可达87.4%。

关键词：粉尘防治循环负压射流卷吸机制参数优化

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