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EFFECT OF N,N,N＇N＇-TETRAALKYL TEREPHTHALAMIDE ON NONISOTHERMAL CRYSTALLIZATION KINETICS OF POLYPROPYLENE

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Chinese Journal of Polymer Science 2006年第4期24卷 345-351页

作者：申屠宝卿 State Key Laboratory of Polymer Reaction Engineering Department of Chemical Engineering Zhejiang University Hangzhou 310027 China

The effect of N,N,N＇,N＇-tetraalkyl terephthalamide （TATA） on the non-isothermal crystallization and melting characteristics ofpolypropylene （PP） was studied. The addition of TATA can lead to the formation ofβ-crystal PP. With the increase in TATA concentration the degree of crystallinity for β-crystal PP increased significantly, and that for a-crystal PP decreased, which indicated that TATA effectively induced the formation of β-crystal PP. WAXD also revealed the existence of β-crystal PP after the introduction of TATA into PP. PP containing TATA crystallized at a temperature range of 5-10℃ higher than that of pure PP, and the half-crystallization time （t1/2） and Avrami exponent （n） of PP at the same cooling rate were decreased by the addition of TATA, indicating that TATA influenced the crystallization rate and crystallization growth mode of PP. The rate constant of crystallization of PP containing TATA （Zc） was larger than that of pure PP, which further indicated that the crystallization of PP was accelerated by the addition of TATA.

关键词： Polypropylene N,N,N',N'-tetraalkyl terephthalamide Non-isothermal crystallization kinetics β-crystal.

NUMERICAL SIMULATION OF 3-D TURBULENT FLOWS IN A CUT-OFF VALVE AND ANALYSIS OF FLOW CHARACTERISTICS IN PIPE

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Journal of Hydrodynamics 2003年第4期15卷 86-91页

作者： HeZhi-guo MaoGen-hai YuanXing-ming DepartmentofCivilEngineering ZhejiangUniversityHangzhou310027China DepartmentofHydraulicEngineering YangzhouUniversityYangzhou225009China

The 3-D turbulent flows in a valve pipe were described by the incompressibleReynolds-averaged Navier-Stokes equations with an RNG k-ε turbulence model. With the finite volumemethod and a body-fitted coordinate system, the discretised equations were solved by the SIMPLESTalgorithm. The numerical result of a cut-off valve with curved inlet shows the flow characteristicsand the main cause of energy loss when fluid flows through a valve. And then, the boundaries ofvalve were modified in order to reduce the energy loss. The computational results of modified valveshow that the numerical value of turbulent kinetic energy is lower, and that the modified design ofthe 3-D valve boundaries is much better. The analysis of the result also shows that RNG k-εturbulence model can successfully be used to predict the 3-D turbulent separated flows and thesecondary flow inside valve pipes.

关键词： RNG k-ε turbulence model navier-stokes equations body-fitted coordinates finite volume method SIMPLEST valve pipe secondary flow

Revealing structure correlation between ionic liquid and metal-organic framework matrix

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Magnetic Resonance Letters 2024年第2期4卷 65-72页

作者： Ligang Xu Wenda Zhang Chenjie Lou Chenxu Geng Yuxiu Sun Jie Liu Yongchao Shi Huajie Luo Jipeng Fu Haiyan Zheng Mingxue Tang Center for High Pressure Science and Technology Advanced Research Beijing100193China College of Materials Science and Engineering Guilin University of TechnologyGuilin541004China State Key Laboratory of Separation Membranes and Membrane Processes School of Material Science and EngineeringTiangong UniversityTianjin300387China University of Science and Technology Beijing Beijing100083China Key Laboratory of Rare Earth Optoelectronic Materials and Devices of Zhejiang Province Institute of Optoelectronic Materials and DevicesChina Jiliang UniversityHangzhou310018China

Solid-state batteries are rising rapidly in response to the fast-increasing energy ***-organic framework(MOF) loaded with ionic liquids has brought new opportunities for solid-state batteries owing to its good interfacial compatibility and high ionic conductivity. MOF-808 is selected to be filled with Li-contained ionic liquid for structure and ion dynamics investigation using nuclear magnetic resonance(NMR) and X-ray *** study finds that the introduced ionic liquid would partially soften the matrix of MOF-808 and thus yield amorphous phase. By selective isotope replacement under cycling symmetric ^(6)Li metal cell, Li^(+)ion is observed to mainly go cross ionic liquid in the open channel of matrix under potential polarization.

关键词： Nuclear magnetic resonance Solid-state batteries MOF-808 Ionic liquid Local structure

Using Greedy algorithm: DBSCAN revisited II

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Journal of Zhejiang University Science 2004年第11期5卷 1405-1412页

作者：岳士弘李平郭继东周水庚 InstituteofIndustrialProcessControl ZhejiangUniversityHangzhou310027China YiliTeacher＇sCollege Yining835000China

The density-based clustering algorithm presented is different from the classical Density-Based Spatial Clustering of Applications with Noise (DBSCAN) (Ester et al., 1996), and has the following advantages: first, Greedy algorithm substitutes for R*-tree (Bechmann et al., 1990) in DBSCAN to index the clustering space so that the clustering time cost is decreased to great extent and I/O memory load is reduced as well; second, the merging condition to approach to arbitrary-shaped clusters is designed carefully so that a single threshold can distinguish correctly all clusters in a large spatial dataset though some density-skewed clusters live in it. Finally, authors investigate a robotic navigation and test two artificial datasets by the proposed algorithm to verify its effectiveness and efficiency.

关键词： DBSCAN algorithm Greedy algorithm Density-skewed cluster

面向工业电热综合能源系统的蒸汽管存效应研究

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浙江电力 2024年第3期43卷 114-121页

作者：杨立勇李广山李刚姜楠董帅蔡浩飞林小杰华能伊敏煤电有限责任公司内蒙古呼伦贝尔021130 中国华能集团清洁能源技术研究院有限公司北京102209 浙江大学能源工程学院杭州310027

为研究蒸汽系统的热惯性从而解决工业园区低碳能源系统调度难题,提出了反映蒸汽时空传输特性的蒸汽系统动态分析模型,建立包括5个存储关键参数和3个指标的蒸汽储能虚拟模型,用于量化热惯量。对163节点城市规模蒸汽系统运行过程中的热惯... 详细信息

为研究蒸汽系统的热惯性从而解决工业园区低碳能源系统调度难题,提出了反映蒸汽时空传输特性的蒸汽系统动态分析模型,建立包括5个存储关键参数和3个指标的蒸汽储能虚拟模型,用于量化热惯量。对163节点城市规模蒸汽系统运行过程中的热惯量进行了量化,其中该蒸汽网络在0.5 h调度周期下的净储热量可达7 440.3 kg,放能能力达到了10.16 t,平均放能利用率达到了14.59%,为工业园区蒸汽系统分析和运行优化提供了定量依据。

关键词：蒸汽系统动态水力建模储能虚拟模型管存特性评估

基于MLP和多头自注意力特征融合的双模态情感计算模型

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计算机应用 2024年第S1期44卷 39-43页

作者：吴俊洁王佳阳朱萍肖强浙江大学图书馆杭州310027 杭州电子科技大学电子信息学院杭州310018 浙江方圆检测集团股份有限公司杭州310018

针对情感计算中传统的单模态情感分析通常存在分类准确率不高和不同语言环境间泛化能力较差的问题,提出一种双模态情感计算模型,以同时使用包含中英文两种语言、两种不同模态的情感数据。首先,利用多层感知机(MLP)网络和双向长短时记忆(... 详细信息

针对情感计算中传统的单模态情感分析通常存在分类准确率不高和不同语言环境间泛化能力较差的问题,提出一种双模态情感计算模型,以同时使用包含中英文两种语言、两种不同模态的情感数据。首先,利用多层感知机(MLP)网络和双向长短时记忆(BiLSTM)网络对数据进行特征提取;其次,基于MLP和自注意力机制分别对提取的特征进行特征融合,得到多模态分析模型;最后,使用该模型在构建的包含中英文两种语言数据的数据集上进行二分类情感计算预测。实验结果表明,所提模型相较于次优的BiLSTM模型,精度提高了1.22%;相较于单模态情感计算模型,精度提高了6.21%~14.00%。

关键词：情感计算多语言泛化多层感知机自注意力机制双模态

Impacts of cloud radiative processes on the convective and stratiform rainfall associated with Typhoon Fitow(2013)

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Frontiers of Earth Science 2022年第4期16卷 1052-1060页

作者： Huiyan XU Dengrong ZHANG Zhejiang Provincial Key Laboratory of Urban Wetlands and Regional Change Hangzhou Normal UniversityHangzhou 311121China

The three-dimensional Weather Research and Forecasting(WRF)model was used to conduct sensitivity experiments during the landfall of Typhoon Fitow(2013)to examine the impacts of cloud radiative processes on thermal *** vertical profiles of heat budgets,vertical velocity,and stability were analyzed to examine the physical processes responsible for cloud radiative effects on surface rainfall for Typhoon Fitow(2013).The inclusion of clouds reduced radiative cooling in ice and liquid cloud layers by reducing outgoing *** suppressed radiative cooling reduced from the ice cloud layers to liquid cloud *** was conducive to reducing *** decreased instability was associated with the reduced upward *** reduced upward motion led to a decreased vertical mass ***,heat divergence was weakened to warm the *** with suppressed radiative cooling,these effects jointly suppressed net condensation and ***,the reduced rainfall due to the cloud radiative effects were mainly associated with the reduced convective and stratiform *** reduced convective rainfall was associated with the reduced net condensation,while the reduced stratiform rainfall was related to the constraint of hydrometeor convergence.

关键词： heat budget radiative cooling heat divergence latent heat release typhoon

Effects of ethanol on the in situ synthesized Cu/SiO_2 catalyst:Texture,structure,and the catalytic performance in hydrogenation dimethyl oxalate to ethylene glycol

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Chinese Chemical Letters 2011年第3期22卷 362-365页

作者： Shu Rong Wang Ling Jun Zhu Ying Ying Zhu Xiao Lan Ge Xin Bao Li State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

The Cu/SiO_2 catalysts were in situ synthesized by the hydrolysis of tetraethyl orthosilicate（TEOS） in one phase solution using ethanol as co-solvent or TEOS/H_2O two phases solution,followed by the precipitation of copper on SiO_2 by ammonia evaporation. In the hydrogenation of dimethyl oxalate,the catalyst prepared by one phase hydrolysis exhibited higher activity and ethylene glycol（EG） selectivity at lower temperature than that of two phases due to its larger BET surface area and multimodal pore *** 488-503 K,the catalyst prepared in one phase solution with water/ethanol（W/E） volume ratio of 3：1 exhibited 90- 95%EG selectivity,while catalyst prepared by two phase hydrolysis reached 90%EG selectivity only at 498-503 K.

关键词： Ethanol Cu/SiO2 TEOS Hydrogenation Dimethyl oxalate Ethylene glycol

RAPID EXACT CONTROLLABILITY OF THE WAVE EQUATION BY CONTROLS DISTRIBUTED ON A TIME-VARIANT SUBDOMAIN

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Chinese Annals of Mathematics,Series B 1999年第1期20卷 65-76页

作者： LIUKANGSHENG YONGJIONGMIN DepartmentofAppliedMathematics ZhejiangUniversityHangzhou310027China LaboratoryofMathematicsforNonlinearSciencesandDepartmentofMathematics FudanUniversityShanghai200433China

Consider the wave equation with distributed controls supported on a subdomain, calledcontrol subdomain, which is allowed to be variant in time. For any prescribed time duration,the authors work out a scheme for changing the control subdomain such that the wave equationis exactly controllable on this time duration, where the control subdomain at any time is allowedto have arbitrarily small measure and relatively simple shape.

关键词： Rapid exact controllability Wave equation Control subdomain Unique continuation