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Catalytic properties of Cu/Co/Zn/Zr oxides prepared by various methods

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Journal of Natural Gas Chemistry 2008年第4期17卷 397-402页

作者： Limin Shi Wei Chu siyu Deng Huiyuan xu School of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China

The new Cu-Co based （Cu/Co/Zn/Zr） catalysts for higher-alcohol synthesis were prepared using coprecipitation method, plasma enhanced method and reverse coprecipitation method under ultrasound irradiation. The catalysts were investigated by the means of BET, SEM, XRD, H2-TPR and XPS. Catalytic properties of the catalysts prepared by various methods were examined using CO hydrogenation reaction. It was found that plasma enhanced method and reverse coprecipitation method under ultrasound irradiation were both effective in enhancing the catalytic properties of Cu/Co/Zn/Zr mixed oxides. The small particle size, high dispersion of active components, the improvement of specific surface area and surface contents of active phases could account for the excellent performance of the experimental Cu/Co/Zn/Zr catalysts.

关键词： higher alcohols reverse coprecipitation plasma catalytic activity

Synthesis and Thermal Behavior of 1,8-Dihydroxy- 4,5-dinitroanthraquinone Manganese Salt

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Chemical Research in Chinese Universities 2014年第3期30卷 468-471页

作者： WANG Yinglei ZHAO Fengqi JI Yueping YI Jianhua WANG Wei xu siyu AN Ting PEI Qing Science and Technology on Combusition and Explosion Laboratory Xi 'an Modern Chemistry Research Institute Xi 'an 710065 P. R. China

A novel energetic combustion catalyst, 1,8-dihydroxy-4,5-dinitroanthraquinone manganese salt （DHDNEMn）, was synthesized by virtue of the metathesis reaction in a yield of 91%, and its structure was characterized by IR, element analysis and differential scanning calorimetry（DSC）. The thermal decomposition reaction kinetics was studied by means of different heating rate DSC. The results show that the apparent activation energy and pre-exponential factor of the exothermic decomposition reaction of DHDNEMn obtained by Kissinger＇s method are 162.3 kJ/mol and 1011.8 s^-1, respectively. The kinetic equation of major exothermic decomposition reaction of DHDNEMn is dα/dT= 10^118/β 2/5（1-α）[-ln（1-α）[-ln（1-α）]^3/5 exp（-1.623×10^5/RT）. The entropy of activation（△S^≠）, enthalpy of activation（△H^≠） and free energy of activation（A△G^≠） of the first thermal decomposition are -24.49 J·mol^-1·K^-1, 185.20 kJ/mol and 199.29 kJ/mol（T=575.5 K）, respectively. The self-accelerating decomposition temperature（TSADT） and critical temperature of thermal explosion（Tb） are 562.9 and 580.0 K, respectively. The above-mentioned information on the thermal behavior is quite useful for analyzing and evaluating the stability and thermal safety of DHDNEMn.

关键词： Manganese salt of 1,8-dihydroxy-4,5-dinitroanthraquinone Thermal behavior Energetic combustion catalyst

Optical fiber FBG linear sensing systems for the on-line monitoring of airborne high temperature air duct leakage

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Chinese Physics B 2022年第8期31卷 410-417页

作者： Qinyu Wang Xinglin Tong Cui Zhang Chengwei Deng siyu xu Jingchuang Wei School of Information Engineering Wuhan University of TechnologyWuhan 430070China National Engineering Laboratory for Fiber Optic Sensing Technology Wuhan University of TechnologyWuhan 430070China

Electrical sensing systems, such as those involving eutectic salt, are mostly used in connection to leakage from existing airborne high-temperature air-conducting pipelines. Such complex structured systems are susceptible to external interferences and, thus, cannot meet the increasingly strict monitoring needs of a complex air-conducting pipeline system of an aircraft. In view of this point, this paper studies an alternative sensor system based on a dense array fiber grating. To obtain a compact and light-weight airborne signal processing system, a field programmable gate array is used as the main control core that controls the output of the light source. The functions of pulse modulation, analog-to-digital conversion,data buffering and transmission are integrated into a single system, while the linear sensing monitoring is obtained by detecting the time-division and wavelength-division wavelength drift signals of the fiber Bragg grating array. Our experiments show that the spatial resolution of the linear sensing system approaches 5 cm, the temperature measurement accuracy reaches 2 ℃, the temperature measurement range is between 0–250 ℃, and the response time is within 4 s. Compared with the existing electrical monitoring systems, various monitoring indicators have been greatly improved and have broad application prospects.

关键词： gating array quasi-distributed measurement temperature monitoring prague grating miniaturization

Thermochemical properties and thermokinetic behavior of energetic triazole ionic salts

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Science China Chemistry 2011年第3期54卷 461-474页

作者： ZHAO FengQi xuE Liang XING XiaoLing HU RongZu ZHOU ZhiMing GAO Hongxu YI JianHua xu siyu PEI Qing National Key Lab of Science and Technology on Combustion and Explosion Xi'an Modern Chemistry Research Institute Xi'an 710065 China School of Chemistry and Materials Science Shaanxi Normal University Xi'an 710062. China School of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

The properties of dissolution in different solvents,the specific heat capacity and thermal decomposition process under the non-isothermal conditions for energetic triazole ionic salts 1,2,4-triazolium nitrate(1a),1,2,3-triazolium nitrate(1b),3,4,5triamino-1,2,4-triazolium nitrate(2a),3,4,5-triamino-1,2,4-triazolium dinitramide(2b)were precisely measured using a Calvet *** thermochemical equation,differential enthalpies of dissolution(△difH m ),standard molar enthalpies of dissolution(△difH m ),apparent activation energy(E),pre-exponential constant(A),kinetic equation,linear relationship of specific heat capacity with temperature over the temperature range from 283 to 353 K,standard molar heat capacity(C p,m)and enthalpy,entropy and Gibbs free energy at 283–353 K,taking 298.15 K as the benchmark for 1a,1b,2a and 2b were obtained with treating experimental data and theoretical calculation *** kinetic and thermodynamic parameters of thermal decomposition reaction,critical temperature of thermal explosion(Tb),self-accelerating decomposition temperature(TSADT)and adiabatic time-to-explosion(t)of 1a,1b,2a and 2b were *** heat-resistance abilities were *** was obtained on the relation between molecular structures and properties of 1a,1b,2a and 2b.

关键词： energetic triazole ionic salts thermochemical properties thermokinetic behavior thermal safety

Researches on Thermal Decomposition Kinetics of Composite Modified Double-base Propellants

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Chinese Journal of Chemistry 2011年第3期29卷 411-414页

作者： Tang, Zhan Ren, Yan Yang, Li Zhang, Tonglai Qiao, Xiaojing Zhang, Jianguo Zhou, Zunning Zhao, Fengqi Dang, Yongzhan xu, siyu Yi, Jianhua State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China National Key Laboratory of Science and Technology on Combustion and Explosion Xi'an Modern Chemistry Research Institute Xi' an Shaanxi 710065 China

The thermal decomposition kinetics of composite modified double-base （CMDB） propellants with a series of contents of hexogeon （RDX） was investigated by using parameters of Tco, Ti, Tp, Tf, Tb, Ta, E, lg A and AH, which were obtained from using a CDR-4P differential scanning calorimeter （DSC） and Perkin-Elmer Pyris l thermogravimetric analyzer （TG） analyses with heating rates of 5, 10, 15 and 20 K/min. Reliable activation energy was calculated using Flynn-Wall-Ozawa method before analyzing the thermal decomposition mechanism. TG-DTG curves were treated with Malek method in order to obtain the reaction mechanisms. The obtained results show that the thermal decomposition mechanisms with the conversion from 0.2 to 0.4 was f（a）= 1/2a, and with the conversion from 0.5 to 0.7 was f（a）=（1/4）（1--a）[--1n（1 --a）]-3.

关键词： thermal stability decomposition machenism DSC TG Malek method

基于双核模型研究大质量转移反应中结团发射机制

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核技术 2023年第3期46卷 67-75页

作者：徐思宇冯兆庆华南理工大学、物理与光电学院广州510641

本文借助双核模型,进行了对多核子转移反应中前平衡结团发射机制进行了系统研究。以反应系统^(12)C+^(209)Bi、^(40)Ca+^(208)Pb和^(48)Ca+^(238)U为例,重点分析了库仑位垒附近重离子碰撞产生前平衡轻粒子,如中子、质子、氘核、氚核、^(... 详细信息

本文借助双核模型,进行了对多核子转移反应中前平衡结团发射机制进行了系统研究。以反应系统^(12)C+^(209)Bi、^(40)Ca+^(208)Pb和^(48)Ca+^(238)U为例,重点分析了库仑位垒附近重离子碰撞产生前平衡轻粒子,如中子、质子、氘核、氚核、^(3)He、^(4)He、^(6)Li、^(7)Li、^(8)Be和^(9)Be时间演化、动能分布和角分布。研究结果表明:结团发射呈现出一定核结构效应,^(4)He发射概率与质子相当并远大于^(3)He。前平衡结团主要分布在“类弹”和“类靶”角度区域发射,其动能分布呈现出玻尔兹曼分布形式。考虑结团预形成因子后该方法可以拓展用于不稳定原子核引起的结团发射机制研究。

关键词：结团发射前平衡过程转移反应双核模型

Metagenetics of fairy rings reveals complex and variable soil fungal communities

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Pedosphere 2023年第4期33卷 567-578页

作者： siyu xu Ke DONG Sangseob LEE Matthew Chidozie OGWU Sainbileg UNDRAKHBOLD Dharmesh SINGH Dagvatseren ARIUNZAYA Orsoo ENKHMANDAL Laura A.SPENCE Anarmaa SHARKHUU Brenda B.CASPER Jonathan M.ADAMS Bazartseren BOLDGIV College of Biotechnology Dalian Polytechnic UniversityDalian 116034(China) School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210008(China) Department of Life Sciences Kyonggi UniversitySuwon 443-760(Korea) School of Bioscience and Veterinary Medicine University of CamerinoCamerino 62032Marche-Floristic Research Center of the ApenninesGran Sasso and Monti della Laga National ParkSan ColomboBariscianoL'Aquila 67021(Italy) Laboratory of Ecological and Evolutionary Synthesis Department of BiologySchool of Arts and SciencesNational University of MongoliaUlaanbaatar 14201(Mongolia) School of Biological Sciences Seoul National University1 Gwanak-roGwanak-guSeoul 08826(Korea) Sterling College Sterling DriveCraftsbury Common VT 05827(USA) Department of Biology University of PennsylvaniaPhiladelphia PA 19104(USA)

Although fairy rings are widely observed,little is known about the community processes associated with ***,we studied fairy rings in a natural grassland in northern Mongolia by sampling soils outside(future stage),directly under(present stage),and within(past stage)the rings,to represent different time stages during the expansion of fairy *** DNA was extracted for amplicon sequencing of the fungal ITS1 *** present stage had reduced fungal diversity and different fungal communities toward the other *** strikingly,there was an increase in the pathogenic fungus Gibberella baccata in the present stage of most rings and the saprotrophic fairy ring fungus Lepista luscina in ***,no mushrooms of Lepista had been recorded from any of these rings during several years of *** fairy ring fungi were not found in the present stage of every ring,even in some known rings to have previously displayed mushrooms of such *** is possible that these fungi occurred or were more abundant at the unsampled leading edge of the *** increase in *** is intriguing,but its importance,if any,is *** is also unclear whether consortia of fungi or other microbes might be present in these *** absence or low abundance of the previously reported fairy ring fungal species suggests that their presence is transient,with rapid replacement by other *** differences in soil parameters were found between the fairy ring stages,except for *** is a need for broader sampling,including analysis of non-fungal biota,to understand the functional diversity of fairy ring fungi and the consequences for plant communities.

关键词： community process functional guilds Gibberella baccata grassland ITS1 region network analysis soil fungus

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新型冠状病毒疫苗及抗体药物研发进展

生物医学工程学杂志 2022年第5期39卷 1059-1064页

作者：徐偲瑜(综述) 唐丹(审校) 四川大学华西第二医院运营管理部成都610065 四川大学华西医院泌尿外科研究所成都610065

新型冠状病毒肺炎(COVID-19)疫情在全球的肆虐,不仅对公众的健康造成了重大威胁,也对全球卫生医疗系统和社会经济发展带来了巨大冲击。因此,加快疫苗和抗体药物的研发,为人们提供有效的保护和治疗措施,成为广大科学研究人员和医疗机构... 详细信息

新型冠状病毒肺炎(COVID-19)疫情在全球的肆虐,不仅对公众的健康造成了重大威胁,也对全球卫生医疗系统和社会经济发展带来了巨大冲击。因此,加快疫苗和抗体药物的研发,为人们提供有效的保护和治疗措施,成为广大科学研究人员和医疗机构的首要任务。目前全球已有多款新冠疫苗和抗体药物进入临床研究或获批上市,本文对多款利用基因工程技术研发的基于S蛋白的新冠疫苗和抗体(包括亚单位疫苗、病毒载体疫苗、DNA疫苗、mRNA疫苗以及一些中和抗体药物)进行了简要阐述,同时也对疫苗和抗体药物的未来发展进行了探讨。

关键词：新型冠状病毒疫苗抗体基因工程刺突蛋白

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数字经济对城市相对贫困的影响

工业技术经济 2022年第8期41卷 12-18页

作者：徐思雨辽宁大学经济学院沈阳110036

本文在理论分析数字经济如何缓解城市贫困的基础上,使用中国31个省(区、市)的面板数据,进一步实证检验了数字经济对城市相对贫困的影响,主要结论包括:数字经济可显著缓解城市贫困,进行稳健性检验及考虑内生性后,结论仍然成立;相比之下,... 详细信息

本文在理论分析数字经济如何缓解城市贫困的基础上,使用中国31个省(区、市)的面板数据,进一步实证检验了数字经济对城市相对贫困的影响,主要结论包括:数字经济可显著缓解城市贫困,进行稳健性检验及考虑内生性后,结论仍然成立;相比之下,西部地区数字经济减贫效果较大,东部地区较小;数字经济减贫存在单门槛效应,超过门槛值后,减贫效应明显提升;贫困程度高的地区,数字经济的减贫效应更明显;数字经济缓解贫困的机制为增加就业和激发创业热情;为发挥数字经济的减贫效应,本文从推进数字基础设施建设、提升公共服务数字化水平、建立长效扶贫机制等方面给出了对策建议。

关键词：数字经济城市相对贫困就业创业熵权法减贫效应