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Gelfand-Kirillov Dimension and Reducibility of Scalar Generalized Verma Modules for Classical Lie Algebras

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Acta Mathematica Sinica,English Series 2024年第3期40卷 658-706页

作者： Zhan qiang BAI Jing jiang School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China E-mail:zqbai@*** jjsd6514@***

Let g be a classical complex simple Lie algebra and q be a parabolic *** M be a generalized Verma module induced from a one dimensional representation of *** M is called a scalar generalized Verma *** this paper,we will determine the reducibility of scalar generalized Verma modules associated to maximal parabolic subalgebras by computing explicitly the Gelfand-Kirillov dimension of the corresponding highest weight modules.

关键词： Generalized Verma module Gelfand-Kirillov dimension Young tableau

Study on UV Shielding TiO_2 Thin Film Prepared by Sol-Gel Method

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稀有金属材料与工程 2006年第A3期35卷 508-510页

作者： Shihai Zhao Xiaohui Wang Shaobo Xin qiang jiang Xiaoping Liang School of Mechanical and Electronic Engineering Tianjin Polytechnic University Tianjin 300160 China School of Material Science and Chemical Engineering Tianjin Polytechnic University Tianjin 300160 China

Titanium dioxide (TiO_2) thin films were prepared on microscopes slides by sol-gel and dip-coating processes from specially formulated *** results show that there exists anatase and rutile structure of TiO_2 when heat treatment temperature is 450℃,and at 800℃,TiO_2 particle size is of below 100 nm and rutile structure is *** the range of 360 nm～400 nm the transmittance of TiO_2 sol increases with the increasing of the concentration of Ti(OC_4H_9)_4 in ethanol solution. The transmittance of TiO_2 films with various number of the layer is measured to be 0% below 320 nm,and the three-layer TiO_2 film is of the best UV resistance in the range of 320 nm～400 nm.

关键词： TiO2 thin film sol-gel UV absorption

Gradient nanostructured tungsten and the thermal shock response

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Tungsten 2023年第4期5卷 548-557页

作者： Yan jiang Ping Huang Zhi-qiang jiang Jing Hou Zhong Xu En-Hui Wu Jun Li Vanadium and Titanium Resource Comprehensive Utilization Key Laboratory of Sichuan Province Panzhihua UniversityPanzhihua617000China

In fusion reactor or spallation neutron source environment,damage of tungsten components begins at the *** enhance the surface toughness,strength,and hardness of tungsten,a nano-to-micro sc ale lamellar gradient surface layer(thickness up to~50μm)was produced on as-rolled pure tungsten using a dry-sliding surface *** dry-sliding temperature and time were established by observing the grain-size evolution from room temperature to 750℃and the coefficient of friction on the surface layer after sliding from 10 to 50 *** grains changed into a slender fibrous structure at 250℃,which is higher than the ductile-brittle transition temperature but lower than the dynamic recrystallization temperature(750℃).The coefficient of friction of the surface layer decreased with sliding time and stabilized at approximately 50 min,indicating near-s aturation of the surface *** repetitive thermal loads of 10,20,and 30 MW·m^(-2)on the gradient modified layer,it exhibited mainly recrystallization and grain *** proportion of low-angle grain boundaries(<10°)reached50.6,42.2,and 17.3%,respectively,and the hardness decreased to 602,582,and 488HV.A heat load of 30 MW·m^(-2)was the threshold for the fast grain *** with unmodified tungsten,the recrystallization and grain growth are relatively ***,the gradient layer could suppress the formation of pits and protrusions in the as-rolled tungsten sample.

关键词： Gradient layer Tungsten Dry sliding Coefficient of friction

全内镜下椎板开窗术治疗单节段脊髓型颈椎病的临床疗效

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中国内镜杂志 2024年第4期30卷 7-13页

作者：卢正操蒋强付本升曹蕊丁宇锦州医科大学辽宁锦州121000 解放军总医院第六医学中心中医骨伤科北京100048

目的观察全内镜下椎板开窗术(Endo-LOVE)治疗单节段脊髓型颈椎病(CSM)的临床疗效。方法回顾性分析2021年1月-2021年12月接受Endo-LOVE的26例单节段CSM患者的临床资料。观察术前、术后3 d、术后6个月和术后1年随访时的颈椎功能障碍指数(N... 详细信息

目的观察全内镜下椎板开窗术(Endo-LOVE)治疗单节段脊髓型颈椎病(CSM)的临床疗效。方法回顾性分析2021年1月-2021年12月接受Endo-LOVE的26例单节段CSM患者的临床资料。观察术前、术后3 d、术后6个月和术后1年随访时的颈椎功能障碍指数(NDI)和日本骨科学会(JOA)评分;术后1年,根据脊髓功能改善率评价临床疗效,并行颈椎动力位X线检查,评价手术节段的稳定性。结果26例患者手术均顺利完成,无严重并发症发生,术后症状均明显改善;术后均随访12~18个月,术后各时间点JOA评分和NDI与术前比较,差异均有统计学意义(P<0.05),术后1年行颈椎动力位X线检查,未见手术节段失稳病例,术后1年评价疗效,优16例,良7例,可3例,优良率为88.46%。结论Endo-LOVE治疗单节段CSM安全、有效、微创,短期随访疗效满意,具有一定的临床实用价值。

关键词：脊髓型颈椎病(CSM) 微创手术全内镜下椎板开窗术(Endo-LOVE) 临床疗效全脊柱内镜

近零能耗技术在公共建筑中的应用——以运河湾水运集散中心项目为例

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浙江建筑 2024年第2期41卷 34-37页

作者：江强陆明祥唐兆彦缙云县住房和城乡建设局浙江丽水321400 浙江新广发置业有限公司浙江杭州310015 浙江省建筑设计研究院有限公司浙江杭州310006

以运河湾水运集散中心项目为例,介绍了近零能耗技术在公共建筑项目中的实践,探索适宜夏热冬冷地区公共建筑节能的关键技术,并深入探讨能耗和碳排放,还进行了经济效益分析,以期为低碳建筑建设提供参考。

关键词：近零能耗低碳技术光电建筑一体化夏热冬冷地区公共建筑

Diels-Alder Addition of Dicyclopentadiene with Cyclopentadiene in Polar Solvents

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Chemical Research in Chinese Universities 2008年第2期24卷 175-179页

作者： ZHANG Xiang-wen jiang qiang XIONG Zhong-qiang ZOU Ji-jun WANG Li MI Zhen-tao Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P. R. China

Diels-Alder addition of dicyclopentadiene and cyclopentadiene in polar solvents has been studied to produce tricyclopentadiene（TCPD） that is a potential high-density fuel precursor. GC and MS analysis shows that the adducts contain two isomers, namely exo- and endo-TCPD. Theoretical simulation shows that although the transition state of endo-TCPD has a lower activation energy, exo-TCPD is thermodynamically preferred. Polar solvents can accelerate the reaction rate and improve the exo/endo ratio of TCPD because the transition state of exo-TCPD has a higher polarity than that of endo-TCPD. The solvent effect follows the order of polarity： benzyl methanol〉cyclohexanone〉toluene. The conversion rises when the temperature ranges from 120 to 150 ℃, but the selectivity of TCPD slightly decreases. Increasing the pressure can improve the conversion but the exo/endo ratio of TCPD is unchanged. The apparent kinetics in different solvents was determined via nonlinear regression. The activation energies are 99.47, 101.15, and 107.32 kJ/mol for benzyl methanol, cyclohexanone, and toluene, respectively. The optimal reaction conditions are as follows： benzyl methanol as solvent, temperature 150 ℃, and pressure 900 kPa. After an 11-hour reaction, a conversion of 58.0%, a TCPD selectivity of 95.7%, and an exo/endo ratio of 1/5.3 has been obtained.

关键词： High density fuel Dicyclopentadiene Cyclopentadiene Diels-Alder addition Solvent effect

Novel endo-to exo-isomerization of dicyclopentadiene

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Chinese Chemical Letters 2007年第6期18卷 673-676页

作者： Xiang Wen Zhang[a] Kai jiang[a] qiang jiang[a] Ji Jun Zou[a]&Email:jj_zouchem@*** Li Wang[a] Zhen Tao Mi[a] [a]Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

Endo-dicyclopentadiene was isomerized to exo-isomer by thermal treatment at evaluated temperature and pressure. The reaction temperature and pressure are key factors for this novel isomerization. This result may have ... 详细信息

关键词： Endo-dicyclopentadiene Exo-dicyclopentadiene Isomerization

Low Carbon Technology Development Roadmap for China

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Advances in Climate Change Research 2011年第2期2卷 67-74页

作者： qiang Liu Kejun jiang Xiulian Hu Energy Research Institute National Development and Reform Commission Beijing 100038 China

It is essential that China follows a low carbon pathway, in which technology plays a key role in the future economy and social development. Based on the Integrated Policy Assessment Model for China, this paper analyzes a technology development roadmap for China to achieve a low carbon scenario. The results show that there are plenty of potential and opportunities for China to move towards a low carbon society when given enhanced and accelerated applications and expansions of key low carbon technologies. Strong policy and measure supports from all sectors in China are needed to achieve this goal.

关键词： climate change scenario low carbon technology roadmap

Sintering behavior of aluminum nitride powder prepared by self-propagating high-temperature synthesis method

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Rare Metals 2018年第12期37卷 1091-1095页

作者： Liang Qiao Shu-Wen Chen Li-qiang jiang Kazuo Shinozaki Sheng-Lei Che Research Center of Magnetic and Electronic Materials College of Materials Science and Engineering Zhejiang University of Technology Department of Metallurgy and Ceramics Science Tokyo Institute of Technology

Fully dense aluminum nitride(AIN) ceramics were synthesized by self-propagating high-temperature synthesis(SHS) method using AIN powder as raw material with Y2O3additive. The sintering behavior was studied at different sintering temperatures and additive contents. The change of phase compositions, secondary phase distributions and grain morphologies during sintering process were investigated. It is shown that fully dense ceramics using AIN powder prepared by SHS method can be obtained when the sintering temperature is above 1830 ℃. Both Y2O3content and sintering temperature have an important influence on the formation of Y-Al-O phase and grain shape. When Y2O3content is identified, the grain morphology converts from polyhedron into sphere-like shape with the rise of sintering temperature. At a certain sintering temperature,the grain size decreases with the increase in Y2O3content. The influencing mechanisms of different YAl-O secondary phases and sintering temperatures on the grain size and morphology were also discussed based on the experimental results.

关键词： Self-propagating high-temperature synthesis AlN Secondary phase Liquid-phase sintering