检索结果-南通市图书馆

CCS Chemistry 2024年第4期6卷 1060-1070页

作者： Sifan Li hai-wu Du Paul W.Davies Wei Shu Department of Chemistry Shenzhen Grubbs InstituteSouthern University of Science and TechnologyShenzhen 518055Guangdong School of Chemistry University of BirminghamEdgbastonBirmingham B152TT

Sterically congestedα-tertiary primary amines are ubiquitous substructures in pharmaceutical and agrochemical agents yet are challenging to ***,straightforward photoredox-catalyzed access to structurally diverseα,α,α-trisubstituted primary amines from denitrogenative alkylarylation or dialkylation of vinyl azides with N-hydroxyphthalimide(NHPI)esters and cyanoarenes or aryl aldehydes has been *** use of vinyl azide as a precursor to a primary aminewas enabled by the dual role of the Hantzsch ester to form an electron donor-acceptor complex and serve as a sacrificial *** strategy provides a modular synthesis ofα-tertiary primary amines,including unprotected 1,2-amino alcohols,from simple materials with excellent functional group *** synthetic applicability of this method was demonstrated by streamlined access to 2,2-disubstituted *** investigations support two parallel reductive photocatalytic cycles allowing for the denitrogenative alkylarylation or dialkylation of vinyl azides via decarboxylative radical addition followed by heteroradical cross-coupling betweenα-amino radicals and aryl anion radicals or ketyl anion radicals.

关键词： photocatalysis α-tertiary primary amines 1 2-amino alcohols vinyl azide electron donor-acceptor complex

Effects of projectile parameters on the momentum transfer and projectile melting during hypervelocity impact

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第2期32卷 89-103页

作者： Wenjin Liu Qingming Zhang Renrong long Zizheng Gong Ren Jiankang Xin Hu Siyuan Ren Qiang wu Guangming Song State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Spacecraft Environment Engineering China Academy of Space TechnologyBeijing100094China

The effects of projectile/target impedance matching and projectile shape on energy,momentum transfer and projectile melting during collisions are investigated by numerical *** comparing the computation results with the experimental results,the correctness of the calculation and the statistical method of momentum transfer coefficient is *** shapes of aluminum,copper and heavy tungsten alloy projectiles striking aluminum,basalt,and pumice target for impacts up to 10 km/s are *** influence mechanism of the shape of the projectile and projectile/target density on the momentum transfer was *** an increase in projectile density and length-diameter ratio,the energy transfer time between the projectile and targets is *** projectile decelerates slowly,resulting in a larger cratering *** energy consumed by the projectile in the excavation stage increased,resulting in lower mass-velocity of ejecta and momentum transfer *** numerical simulation results demonstrated that for different projectile/target combinations,the higher the wave impedance of the projectile,the higher the initial phase transition velocity and the smaller the mass of phase *** results can provide theoretical guidance for kinetic impactor design and material selection.

关键词： Hypervelocity impact Energy partitioning Impact melting Momentum transfer

在线全文

学校读者我要写书评

暂无评论

基于故障检测的某涡扇发动机维修决策方法

航空动力学报 2017年第1期32卷 82-88页

作者：张莹松吴灿唐海龙林军郝明北京航空航天大学能源与动力工程学院北京100191 中国人民解放军第5713工厂技术与培训中心湖北襄阳441000

为有效解决某涡扇发动机过度维修造成发动机性能衰减、维修周期长、维修成本高的难题,以某涡扇发动机大修手册和维修工艺为依据,研究了基于故障检测的发动机维修流程和修理模式,建立专家诊断系统和基于BP(back propagation)神经网络的... 详细信息

为有效解决某涡扇发动机过度维修造成发动机性能衰减、维修周期长、维修成本高的难题,以某涡扇发动机大修手册和维修工艺为依据,研究了基于故障检测的发动机维修流程和修理模式,建立专家诊断系统和基于BP(back propagation)神经网络的故障诊断模型,并用数台涡扇发动机真实性能数据验证故障诊断模型的可靠性,其诊断准确率高达95%,综合两者的诊断信息,制定可靠的维修方案,优化维修流程,提出了一种基于故障检测的维修决策方法.通过某涡扇真实排气温度高发动机应用验证表明:所提出的维修决策方法,有效排除故障,提高发动机的修理质量,降低维修成本,具有良好的工程应用价值.

关键词：涡扇发动机 BP神经网络专家系统故障检测维修决策

交替三线性分解算法结合高效液相色谱法同时测定水杨酸与龙胆酸

在线全文

学校读者我要写书评

暂无评论

分析测试学报 2007年第5期26卷 686-689,693页

作者：孙剑奇吴海龙九江学院化学化工学院应用化学研究所江西九江332005 湖南大学化学化工学院化学生物传感与计量学国家重点实验室湖南长沙410082

利用交替三线性分解算法（ATLD）与高效液相色谱法相结合,在色谱保留时间为0.662 8～0.949 5min（间隔1/150 min）、紫外吸收波长为268～332 nm（间隔2 nm）且在未知干扰物2,3-二羟基苯甲酸存在下,同时测定了水溶液中光谱及色谱严重重... 详细信息

利用交替三线性分解算法（ATLD）与高效液相色谱法相结合,在色谱保留时间为0.662 8～0.949 5min（间隔1/150 min）、紫外吸收波长为268～332 nm（间隔2 nm）且在未知干扰物2,3-二羟基苯甲酸存在下,同时测定了水溶液中光谱及色谱严重重叠的水杨酸（SA）和龙胆酸（GA）的含量,回收率分别为（102.2±6.7）%,（102.1±4.1）%,分辨结果与实际结果一致。研究结果表明：该方法定量快速准确、实验操作步骤简单,说明ATLD算法收敛快速稳定,对复杂体系中组分数估计不敏感,能有效解决色谱中的二阶校正问题。

关键词：水杨酸龙胆酸 2,3-二羟基苯甲酸交替三线性分解二阶校正高效液相色谱

Two-dimensional conjugated coordination polymer monolayer as anode material for lithium-ion batteries:A DFT study

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第6期35卷 180-184页

作者： Xin-Tong Zhao Jin-Zhi Guo Wen-Liang Li Jing-Ping Zhang Xing-long wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China Faculty of Chemistry Northeast Normal UniversityChangchun 130024China Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal UniversityGanzhou 341000China

Nowadays,lithium-ion batteries(LIBs)play a crucial role in modern society in the aspect of portable electronic devices and large-scale smart ***,the current performance of lithium-ion batteries has been unable to meet the growing expectations of society and scientific ***,we have synthetically investigated availability of 2D Ni-TABQ monolayer as anode based on DFT for LIBs *** findings have demonstrated that 2D Ni-TABQ monolayer is a semiconductor with a small band gap of 0.2 eV,which suggest that the electronic property of 2D Ni-TABQ monolayer would take place an evident shift from semiconductor property to metallic property after Li ***,we checked the stability of 2D Ni-TABQ monolayer and investigated the viability of exfoliation from bulk multilayer Ni-TABQ to form 2D Ni-TABQ monolayer in the light of exfoliation energy and binding *** continuously studied electrochemical properties of 2D Ni-TABQ monolayer with respect of theoretical specific capacity,Li-ion diffusion barriers and open-circuit *** the charging process,2D Ni-TABQ monolayer can achieve a high specific capacity of 722 m Ah/g with an open-circuit voltage range from 1.12 V to 0.22 *** aforementioned results make the 2D Ni-TABQ monolayer a promising anode for LIBs.

关键词： The first principles Density functional theory Lithium-ion battery Anode material Two-dimensional material

基于逆向Shear-Warp和边缘体素的快速重建算法

在线全文

学校读者我要写书评

暂无评论

计算机工程与应用 2009年第1期45卷 238-241页

作者：赵亮周荷琴吴龙海中国科学技术大学自动化系合肥230027

医学图像表面重建是协助医生对人体内部病变做出准确诊断的重要手段,而重建的速度直接影响医生的工作效率。为加快重建的速度,提出一种基于逆向Shear-Warp和边缘体素的快速重建算法。采取逆向Shear-Warp方法,减少了不必要的数据处理;通... 详细信息

医学图像表面重建是协助医生对人体内部病变做出准确诊断的重要手段,而重建的速度直接影响医生的工作效率。为加快重建的速度,提出一种基于逆向Shear-Warp和边缘体素的快速重建算法。采取逆向Shear-Warp方法,减少了不必要的数据处理;通过在完全相反的两个方向上提取边缘体数据,得到全部的表面体素,重复利用这些体数据,而不必每次重新遍历整个数据场,提高了边缘体素的利用效率,达到了快速重建的目的。

关键词：快速重建逆向Shear-Warp 边缘体素

Preparation and properties of ZrO_(2)-strengthened porous mullite insulation materials using Y_(2)O_(3) additive

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第6期31卷 1514-1521页

作者： Wang-zhi Yu Yi-hong Shi Ping Liu Yong-wan wu Cheng-hao Song Xian-gong Deng Xiang Ding Song-lin Ran Yi Zhang hai-jun Zhang hai-liang Deng Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMa'anshan 243002AnhuiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrO_(2)-strengthened porous mullite insulation materials were prepared by foaming technology utilizing ZrSiO_(4) and Al_(2)O_(3) as primary materials and Y_(2)O_(3) as an *** effects of Y_(2)O_(3) contents on the phase composition,microstructure,mechanical properties,and heat conductivity of the porous mullite insulation materials were investigated.A suitable Y_(2)O_(3) content could promote phase transition of monoclinic ZrO_(2)(m-ZrO_(2))to tetragonal ZrO_(2)(t-ZrO_(2)),reduce pore size,and improve the strengths of as-prepared *** cold crushing strength and bending strength of as-prepared specimens with a 119µm spherical pore size using 6 wt.%Y_(2)O_(3) were 35.2 and 13.0 MPa,respectively,with a heat conductivity being only 0.248 W/(m K).

关键词： Porous mullite insulation material Zirconium oxide Y_(2)O_(3) Mechanical property Heat conductivity

Hybrid bimetallic cluster ZrO2/Rh@N,S co-doped porous carbon nanosheets for efficient hydrogen evolution in acid electrolytes

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tungsten 2024年第4期6卷 657-662页

作者： Xin-Yi Zhang Igor V.Zatovsky Jun-Ming Cao Xing-long wu Faculty of Chemistry Northeast Normal University F.D.Ovcharenko Institute of Biocolloidal Chemistry NAS Ukraine MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal University

Acid hydrogen evolution reaction (HER) is a critical energy conversion process,which is significantly important in hydrogen energy manufacturing and storage [1].Although the performance of noble metal platinum (Pt)-based catalysts in acidic HER is well known,the challenges are high cost,limited reserves,poor stability,and susceptibility to toxic substances [2].Therefore,it is urgent to design and manufacture acidic HER catalysts with high reactivity,high stability,and low cost.

关键词：

Radiation Spectral Analysis of 3D Dust Molecular Clusters(PAHs)and Peptoids under Ionization and Electric Field in ISM

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第1期24卷 70-77页

作者： Ruiqing wu Chunhua Zhu Guoliang Lü Xiaojiao Zhang Xizhen Lu Jinlong Yu wujin Chen Mengqiu long School of Physics and Electronics Central South UniversityChangsha 410083China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China School of Microelectronics and Physics Hunan University of Technology and BusinessChangsha 410205China College of Mechanical and Electronic Engineering Tarim UniversityAlar 843300China School of Medicine Xinjiang Medical UniversityUrumqi 830011China

Polycyclic aromatic hydrocarbons(PAHs),PANHs,and peptoids dust spectral calculations from the interstellar medium(ISM)are important for dust observations and *** goal is to calculate the radiation spectrum of spherical PAHs dust clusters in a vacuum containing ionized and applied in the presence of an electric *** propose a new simple computational model to calculate the size of three-dimensional spherical dust clusters formed by different initial dust *** the Vienna Ab-initio Simulation Package code,the density functional theory with the generalized approximation was used to calculate the electron density gradient and obtain the radiation spectrum of *** the radius of spherical dust clusters is~[0.009-0.042]μm,the dust radiation spectrum agrees well with the Z=0.02 mMMP stellar spectra,and the PAHs radiation spectrum of NGC 4676 at wavelengths of(0-5]μm and(5-10]μm,*** the ionized state,the N-PAH,C_(10)H_(9)N,2(C_(4)H_(4))^(1+),and peptoids 4(CHON),(C_(8)H_(10)N_(2)O_(5))^(1+)dust clusters at 3.3μm,while the 2(C_(22)H_(21)N_(3)O_(2))^(1+),4(CHON)dust clusters at 5.2μm have obvious *** is a characteristic of part of PAHs and peptoids clusters radiation at the nearinfrared wavelength of 2μ***,especially after applying an electric field to the dust,the emission spectrum of the dust increases significantly in the radiation wavelength range[3-10]μ***,the dust clusters of PAHs,PANHs,and peptoids of the radius size~[0.009-0.042]μm are likely to exist in the ISM.

关键词： ISM:structure ISM:molecules radiation mechanisms:general (ISM:)dust extinction

在线全文

学校读者我要写书评

暂无评论

新型矩形垂直筛板的研究

现代化工 2005年第9期25卷 57-59页

作者：吴海龙李群生王爱军北京化工大学化学工程学院北京100029

研究开发了一种矩形垂直筛板.该塔板上设置数个由板孔、升气筒、矩型罩、底隙所构成的矩形帽罩单元,在单元内气、液呈喷射状态接触,实现两相传热传质.流体力学性能和传质性能实验结果证明:矩形垂直筛板具有较低的压降和较小的漏液比,可... 详细信息

研究开发了一种矩形垂直筛板.该塔板上设置数个由板孔、升气筒、矩型罩、底隙所构成的矩形帽罩单元,在单元内气、液呈喷射状态接触,实现两相传热传质.流体力学性能和传质性能实验结果证明:矩形垂直筛板具有较低的压降和较小的漏液比,可以在空塔动能因子1.3～3.0kg1/2/(m1/2·s)、液流强度2.7～21.6m3/(m·h)范围内正常操作,具有较大的生产处理能力和较宽的稳定操作范围.

关键词：矩形垂直筛板塔板结构塔板压降雾沫夹带漏液量