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Effect of surfactant structure on catalysis of microemulsion for photoisomerization of trans-stilbene

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Chinese Chemical Letters 2007年第10期18卷 1265-1268页

作者： xia guo Ling Lin Rong guo School of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225002 China

In this study, the photoisomerization of trans-stilbene was carded out in water in oil （W/O） microemulsions by using sodium dodecyl sulfate （SDS）, dodecyl trimethyl ammonium bromide （DTAB） and cetyl trimethyl ammonium bromide （CTAB） as surfactant, respectively. The catalytic effect of microemulsion on this reaction is closely related to the structure of surfactant. When there is no photosensitizer 9,10-dicyanoanthracene （DCA）, the surfactant with shorter hydrophobic chain is preferred, while in the presence of DCA, the surfactant with anionic polar group is preferred.

关键词： Microemulsion Photoisomerization trans-Sfilbcne

Vesicle formation between single-chained cationic surfactants and ribo-oligonucleotides

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Chinese Chemical Letters 2013年第1期24卷 82-84页

作者： Hua Li xia guo School of Chemistry and Chemical Engineering Yangzhou University

Recently, we reported that deoxyribo-oligonucleotides could induce single chained cationic surfactant aggregation to form vesicles. In this paper, we will present that ribo-oligonucleotides can also induce vesicle for... 详细信息

关键词： Surfactant Oligonulleotide RNA DNA

老年冠心病患者心脏康复治疗中运动心肺功能测试系统对心肺功能的评估效果及辅助治疗作用

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中国医疗器械信息 2024年第17期30卷 128-130,168页

作者：李辉夏国军知心健(南京)科技有限公司江苏南京211300

目的:观察分析老年冠心病患者心脏康复治疗中运动心肺功能测试系统对心肺功能的评估效果及辅助治疗作用。方法:将2022年1月~8月收治的92例冠心病患者采用随机数表法分为两组,对照组(46例)采用常规心脏康复治疗,观察组(46例)采用运动心... 详细信息

目的:观察分析老年冠心病患者心脏康复治疗中运动心肺功能测试系统对心肺功能的评估效果及辅助治疗作用。方法:将2022年1月~8月收治的92例冠心病患者采用随机数表法分为两组,对照组(46例)采用常规心脏康复治疗,观察组(46例)采用运动心肺功能测试系统辅助的心脏康复治疗,比较两组心肺功能指标、运动耐力指标及健康状况。结果:干预后观察组左室舒张末期内径小于对照组,左室射血分数、用力肺活量、一秒率、峰值氧脉搏、峰值摄氧量、6min步行距离、简明健康调查量表评分均高于对照组(P<0.05)。结论:运动心肺功能测试系统辅助的心脏康复治疗能够有效改善患者心肺功能,提高其运动耐力与健康水平。

关键词：冠心病心脏康复治疗运动心肺功能测试系统心肺运动试验心肺功能

Study of the Reconstruction of Fractal Structure of Closed-cell Aluminum Foam and its Thermal Conductivity

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Journal of Thermal Science 2012年第1期21卷 77-81页

作者： Dehong xia Shanshan guo Ling Ren Department of Thermal Engineering University of Science and Technology Beijing Beijing 100083 China

Based on the characteristics of the internal structure of closed-cell aluminum foam, this paper attempts to illus- trate the process of reconstructing the internal structures of closed-cell aluminum foam in Monte-Carlo method and the fractal characteristics of the reconstructed model. Furthermore, Binary Array Method is proposed by analyzing the reconstructed model and the thermal conductivity model of closed-cell aluminum foam is established. At the same time, the thermal conductivity of the foam materials with different porosity is calculated by Binary Array Method, and the calculated value coincides with the experimental results in the reference, which proves the correctness of these methods.

关键词： fractal closed-cell aluminum foam reconstruction Binary Array Method thermal conductivity

Soil erosion calculation in the hydro-fluctuation belt by adding water erosivity factor in the USLE model

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Journal of Mountain Science 2020年第9期17卷 2123-2135页

作者： XIN Zhi-yuan xia Jian-guo College of Resources Sichuan Agricultural UniversityChengdu 611130China

Soils in the hydro-fluctuation belts of the reservoirs are most highly influenced by the special hydro-conditions and reservoir operation,leading to unique soil erosion process and largely accelerate soil erosion *** present study aimed to estimate soil erosion rate in the hydro-fluctuation belt of the Pubugou Reservoir,Southwest China,based on the framework of Universal Soil Loss Equation(USLE).An attempt has been made to modify the original USLE by including the reservoir water erosivity(W),a new factor into the *** erosion rate from different land use types were quantitatively estimated,using the USLE and the modified USLE *** observation showed that soil erosion rate in dry farmland,bare land and grassland was 4700,44600 and 5050 t/km2,*** erosion rate assessed by the modified USLE was closely related to that recorded from the field monitoring *** findings of this study clearly highlight the importance of inclusion of the W factor to the original USLE model while assessing soil erosion in the reservoir hydro-fluctuation belt.

关键词： Modified USLE Water erosivity Soil erosion Hydro-fluctuation belt Reservoir

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钨极高压微电弧温度模型的建立与验证

中国机械工程 2024年第7期35卷 1188-1193,1204页

作者：李瑞君赵亮姚攀王勇俊杨晓婷夏果程真英合肥工业大学仪器科学与光电工程学院合肥230009

为提高一体式微球形钨探针的制备成功率,对制备过程中高压微电弧进行了研究。建立了钨极高压微电弧的多物理场耦合仿真模型以计算电极间距在0.5~2.0 mm、电压在1~12 kV时的电弧温度分布;然后对仿真结果进行最小二乘拟合,进而得到了电弧... 详细信息

为提高一体式微球形钨探针的制备成功率,对制备过程中高压微电弧进行了研究。建立了钨极高压微电弧的多物理场耦合仿真模型以计算电极间距在0.5~2.0 mm、电压在1~12 kV时的电弧温度分布;然后对仿真结果进行最小二乘拟合,进而得到了电弧温度与放电参数之间的数学模型;最后,基于Boltzmann作图法搭建了光谱测温系统,并对数学模型进行了验证。研究结果表明:电弧呈椭球形分布,近阳极区存在高温屏障,阳极温度远低于阴极温度;电弧温度与电压、电极间距之间均为类抛物线性关系;模型计算结果与实验结果的平均相对误差为3.3%。该模型可用于计算电弧温度,从而实现钨探针的可控制备。

关键词：电弧温度磁流体动力学 Boltzmann作图法微球形钨探针

维普期刊数据库博看期刊

Combined Molecular Dynamics Simulation and Rouse Model Analysis of Static and Dynamic Properties of Unentangled Polymer Melts with Different Chain Architectures

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Chinese Journal of Polymer Science 2021年第4期39卷 512-524,I0008页

作者： Pu Yao Lu-Kun Feng Hong-xia guo Beijing National Laboratory for Molecular Sciences Joint Laboratory of Polymer Sciences and MaterialsState Key Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Chain architecture effect on static and dynamic properties of unentangled polymers is explored by molecular dynamics simulation and Rouse mode analysis based on graph *** open chains,although they generally obey ideal scaling in chain dimensions,local structure exhibits nonideal behavior due to the incomplete excluded volume(EV)screening,the reduced mean square internal distance(MSID)can be well described by Wittmer'theory for linear chains and the resulting chain swelling is architecture dependent,i.e.,the more branches a bit stronger *** rings,unlike open chains they are compact in term of global *** to EV effect and nonconcatenated constraints their local structure exhibits a quite different non-Gaussian behavior from open chains,i.e.,reduced MSID curves do not collapse to a single master curve and fail to converge to a chain-length-independent constant,which makes the direct application of Wittmer's theory to rings quite *** from ideality is further evidenced by limited applicability of Rouse prediction to mode amplitude and relaxation time at high modes as well as the non-constant and mode-dependent scaled Rouse mode amplitudes,while the latter is architecture-dependent and even molecular weight dependent for *** chain relaxation time is architecture-dependent,but the same scaling dependence on chain dimensions does hold for all studied *** mode orthogonality at static state,the role of cross-correlation in orientation relaxation increases with time and the time-dependent coupling parameter rises faster for rings than open chains even at short time scales it is lower for rings.

关键词： Rouse model Unentangled chains Architecture Excluded volume effects

Fe-Mo-B Enhanced Sintering of P/M 316L Stainless Steel

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Journal of Iron and Steel Research International 2008年第1期15卷 10-14页

作者： YANG xia guo Shi-ju Institute of Powder Metallurgy University of Science and Technology Beijing Beijing 100083 China

Liquid-phase enhanced sintering of powder metallurgy（P/M）316L stainless steel by addition of sintering aids was studied.2%-8% of pre-alloyed Fe-Mo-B powder with two different particle sizes was added as sintering aids,and the specimens were sintered in vacuum at 1 200-1 350 ℃.The results show that the fine Fe-Mo-B powder（5-10 μm）has stronger activated *** sintered density increases with the increase in sintering aid content or sintering *** compaction has a better effect on the control of dimensional precision of *** prealloyed Fe-Mo-B powder deviated from Mo2FeB2 component can also be sintering aid of P/M 316L stainless steel.

关键词： P/M 316L stainless steel liquid-phase sintering activated sintering Fe-Mo-B sintering aid

A Note on the Existence of Positive Solutions for a Fourth-Order Semilinear Elliptic System

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Acta Mathematica Sinica,English Series 2010年第7期26卷 1263-1276页

作者： Yu xia guo Guang Zhong CHEN Department of Mathematics Tsinghua University Beijing 100084 P. R. China

In this note, we prove the existence of positive solutions to a class of biharmonical systems. Our main ingredients are proving a Liouville type result for biharmonical system in R＋^N via the method of moving plane combined with integral inequality, and establishing a prior estimates for positive solutions of the system via the blowing-up method.

关键词： topological degree theory a prior estimate fourth-order system Liouville theorem