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New Sorbent for Bilirubin Removal from Human Plasma: Albumin Immobilized Microporous Membranous PTFE Capillaries

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Chinese Chemical Letters 2005年第11期16卷 1495-1498页

作者： lei zhang Gu JIN Department of Chemistry University of Science and Technology of China Hefei 230026

In this study, we developed a tailored capillary sorbent for bilirubin removal. For immobilized bioligand, capillaries were grafted with epoxy groups using RIGP. The HSA immobilized capillaries has a high affinity ads... 详细信息

关键词： Bilirubin removal radiation grafting PTFE capillaries human serum albumin.

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山地地形下中江南塔地震响应特征试验

地震研究 2025年第1期48卷 159-169页

作者：姜治军钟荣强张磊李胜才张锋魏春明扬州大学建筑科学与工程学院江苏扬州225100 江苏省华建建设股份有限公司江苏扬州225000 北京工业大学城市与工程安全减灾教育部重点实验室北京100124

为研究山地地形对砖石古塔地震响应的影响,以位于四川中江县铜鱼山顶的中江南塔作为原型,选取了汶川地震发生时自贡台阵的加速度记录为基底输入,通过小型振动台试验研究了山底、山顶古塔自振频率随地震动幅值的变化趋势,分析了地形效应... 详细信息

为研究山地地形对砖石古塔地震响应的影响,以位于四川中江县铜鱼山顶的中江南塔作为原型,选取了汶川地震发生时自贡台阵的加速度记录为基底输入,通过小型振动台试验研究了山底、山顶古塔自振频率随地震动幅值的变化趋势,分析了地形效应对古塔地震响应的影响及古塔破坏特征。结果表明:在低幅值地震动作用下古塔自振频率不变,当自由地表地震动峰值分别达到100 Gal和150 Gal时,山顶和山底古塔发生破坏;在古塔自振特性、输入地震动的频谱特征以及结构构造特点影响下,古塔发生了“上轻下重”的破坏特征;与山底古塔相较,山顶古塔地震反应明显更大,相同工况下山顶古塔各楼层峰值加速度、最大相对位移、最大层间位移角分别为山底古塔的2~3倍、1.5~4.5倍、1.5~4.5倍,其中最大相对位移和最大层间位移角的放大倍数与地震动幅值相关,因此需重视山顶古塔的地震安全性。

关键词：山地地形中江南塔地震响应振动台试验

Analysis of Key Technologies and Equipments Development of Largescale Melted Extrusion Manufacturing Systems

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Journal of Materials Science & Technology 2003年第z1期19卷 215-217页

作者： lei zhang Sheng CHEN Yongnian YAN Renji zhang Center for Laser Rapid Forming Dept. of Mechanical Engineer Tsinghua University Beijing 100084 China Center for Laser Rapid Forming Dept. of Mechanical Engineer Tsinghua University Beijing 100084 China Center for Laser Rapid Forming Dept. of Mechanical Engineer Tsinghua University Beijing 100084 China Center for Laser Rapid Forming Dept. of Mechanical Engineer Tsinghua University Beijing 100084 China

To develop large-scale RP systems used to producing functional parts and large-sized models has become an urgentcall now. In this paper, a large-scale RP system, MEM600-l, based on the melted extrusion manufacturing (MEM)process has been developed successfully. And the key issues to develop such a system are discussed. Based on theactual forming experiment, it is concluded that the MEM600-l works reliably and the forming efficiency is muchhigher than its parallel equipments.

关键词： Melted extrusion manufacturing, Large-scale RP systems, Forming efficiency

Magnetic and magnetotransport properties of single-crystalline R2PdGe6（R = Pr, Gd and Tb）

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Journal of Materials Science & Technology 2019年第5期35卷 764-768页

作者： lei zhang Weijun Ren Xiaohua Luo Zhidong zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100039 China Jiangxi Key Laboratory for Rare Earth Magnetic Materials and Devices/lnstitute for Rare Earth Magnetic Materials and Devices Jiangxi University of Science and Technology Ganzhou 341000 China

Single crystals of R2PdGe6 (R=Pr, Gd and Tb) compounds were grown by the Bi-flux method. Pr2PdGe6 is an antiferromagnetic compound with Neel temperature Tn=15K, in which a field-induced magnetic transition (spin flip) occurs when a magnetic field is applied along either a or b axis;a small magnetization and hysteresis loop were observed when a field is applied along c axis. Gd2PdGe6 is a colli near antiferromagnetic compound with Tn=37K along b axis. Tb2PdGe6 is an antiferromagnetic compound with Tn =48 K and its hard magnetization direction is along b axis. The temperature dependences of the resista nee of the entire three compounds prese nt inflection points at the respective Tn-A large resista nee (as well as magnetoresistance) change can be found at the spin flip transition of Pr2 PdGe6, but the change is not obvious at the spin flop transition of Gd2PdGe6.

关键词： R2PdGe6 Single crystal Magnetic properties

Molecular dynamics study of the infiltration of lipid-wrapping C60 and polyhydroxylated single-walled nanotubes into lipid bilayers

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Frontiers of physics 2015年第2期10卷 57-66页

作者： Quan-Xing Guo lei zhang Yong zhang School of Physics and Engineering Sun Yat-Sen University Guangzhou 510275 China

Because of the many potential medical applications of nanoparticles, considerable research has been conducted on the interactions between nanoparticles and biomembranes. We employed coarse- grained molecular dynamics simulations to study the infiltration of lipid-wrapping C60 and polyhy- droxylated single-walled nanotubes. Diffusion coefficients and scaling factors are adopted to quantify the diffusivity of the biomembranes, and the rupture tension is used to measure the lateral strength of the lipid bilayer. According to our simulations, all wrapped nanoparticles, except those wrapped by dipalmitoyl-glycero-phosphoglycerol, can be inserted into the bilayers. Our simulations also re- veal that the bilayers remain in free diffusion after the nanoparticle insertions while their diffusion coefficient can be altered significantly. The polyhydroxylated single-walled nanotubes lead to signif- icant changes to the lateral strength of biomembranes and this effect depends on the quantity of the inserted nanoparticles. The simulations demonstrate the feasibility of using these methods to deliver nanopartieles while some suggestions are given for choosing the appropriate lipids for wrappiug. The results also suggest that the functionalized nanopartieles could be applied in strengthening or weakening the lateral strength of biomembranes for specific purposes.

关键词： lipid bilayer carbon nanoparticle molecular dynamics

Synthesis of Enriched 10B Boric Acid of Nuclear Grade

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Transactions of Tianjin University 2014年第6期20卷 458-462页

作者： zhang lei School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Chemical Engineering Research Center Tianjin UniversityTianjin 300072China

An economic and effective method of preparing enriched 10B boric acid was established by chemical reactionof enriched 10BF3 and CaCO3. A process of boron trifluoride reacting with water was investigated under certainconditions. Calcium carbonate was selected to counteract hydrofluoric acid followed on. Some key operation factorswere investigated, such as temperature, reaction time and the ratio of CaCO3 to 10BF3. The results showed that the yieldof enriched 10B boric acid could reach 97. 2% and the purity was up to 94. 1% under the following conditions： the temperaturewas 50-60,℃, the reaction time was 28 h and the ratio of CaCO3 to 10BF3 was 4. In addition, after recrystallizationand titration analysis, the purity of the product could reach over 99. 2% from 94.1%.

关键词： enriched 10B boric acid boron trifluoride calcium carbonate fluoboric acid hydrogen fluoride

Analysis of Mechanical Characteristics of Fly Ash Cenospheres Reinforced Epoxy Composites

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Journal of Wuhan University of Technology(Materials Science) 2018年第1期33卷 139-145页

作者：陈平 LI Jianchao zhang lei School of Mechanical Engineering University of Science and Technology Beijing Department of Mechanical Engineering University of Alaska Fairbanks

Fly ash cenospheres（FACs） as a recycling material of industrial waste has become a competitor for other inorganic particle fillers. Epoxy resin（EP） composites reinforced with different content of FACs as well as different size grading ratio were prepared. The surface modification of FACs particles was conducted before incorporating into EP matrix. The impact and flexural strengths and the flexural modulus were investigated, and the fracture surfaces of the testing samples were analyzed using SEM. Results showed that FACs had an obvious effect on the mechanical characteristics of the FACs/EP composites. With increasing weight fraction of FACs, the impact and flexural strengths and the flexural modulus of EP composite samples increased, and reached the highest values when the weight fraction of FACs reached 15 wt%. The mechanical characteristics of the FACs/EP composites however deteriorated with further increasing of FACs content. For the EP composites reinforced with different size grading ratio of FACs, the larger proportion of small FACs particles, the better mechanical properties of the EP composites. The results were analyzed from the aspect of the plastic deformation, new surface formation and fracture absorption energy. The synergistic effect of the size grading ratio of FACs was not obvious, which would be further investigated.

关键词： fly ash cenospheres epoxy resin mechanical characteristics surface modification

Largest H-eigenvalue of uniform s-hypertrees

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Frontiers of Mathematics in China 2018年第2期13卷 301-312页

作者： Yuan HOU An CHANG lei zhang Center for Discrete Mathematics and Theoretical Computer Science Fuzhou University Puzhou 350000 China Department of Computer Engineering Fuzhou University Zhicheng College Fuzhou 350000 China

The k-uniform s-hypertree G = （V, E） is an s-hypergraph, where 1 ≤ s ≤ k - 1, and there exists a host tree T with vertex set V such that each edge of G induces a connected subtree of T. In this paper, some properties of uniform s-hypertrees are establised, as well as the upper and lower bounds on the largest H-eigenvalue of the adjacency tensor of k-uniform s-hypertrees in terms of the maximal degree A. Moreover, we also show that the gap between the maximum and the minimum values of the largest H-eigenvalue of k-uniform s-hypertrees is just （△S/k）.

关键词： Largest H-eigenvalue spectral radius adjacency tensor hypertree

Testing heteroscedasticity in nonparametric regression models based on residual analysis

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Applied Mathematics(A Journal of Chinese Universities) 2008年第3期23卷 265-272页

作者： zhang lei MEI Chang-lin School of Science Xi＇an Jiaotong University Xi＇an 710049 China Xinhua News Agency Beijing100803 China School of Science Xi＇an Jiaotong University Xi＇an 710049 China

The importance of detecting heteroscedasticity in regression analysis is widely recognized because efficient inference for the regression function requires that heteroscedasticity should be taken into account. In this paper, a simple test for heteroscedasticity is proposed in nonparametric regression based on residual analysis. Furthermore, some simulations with a comparison with Dette and Munk＇s method are conducted to evaluate the performance of the proposed test. The results demonstrate that the method in this paper performs quite satisfactorily and is much more powerful than Dette and Munk＇s method in some cases.

关键词： heteroscedasticity nonparametric regression residual analysis