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连续排水边界条件下饱和软土一维大变形固结解析解

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中南大学学报（自然科学版） 2020年第5期51卷 1289-1298页

作者：江文豪詹良通杨策浙江大学岩土工程研究所浙江杭州310058 浙江大学软弱土与环境土工教育部重点实验室浙江杭州310058 杭州绿农环境工程有限公司浙江杭州310000

基于XIE等提出的饱和软土一维大变形固结的假设,通过引入连续排水边界条件研究瞬时荷载下饱和软土的一维大变形固结问题。利用变量代换、分离变量法和Laplace变换得到连续排水边界条件下饱和软土一维大变形固结解析解,通过退化解析解和... 详细信息

基于XIE等提出的饱和软土一维大变形固结的假设,通过引入连续排水边界条件研究瞬时荷载下饱和软土的一维大变形固结问题。利用变量代换、分离变量法和Laplace变换得到连续排水边界条件下饱和软土一维大变形固结解析解,通过退化解析解和有限差分数值解对比分析,对该解析解的正确性进行验证。基于所得解析解,分析土体的界面参数及荷载参数对土体一维大变形固结性状的影响。研究结果表明:界面参数α和β越大,土体的透水性越好,超孔隙水压力消散越快,地基的固结速度越快;当界面参数增大到一定程度后,连续排水边界可退化为完全排水边界;连续排水边界下以孔压定义的固结度Up随荷载参数λq的增大而减小,以沉降定义的固结度Us则随荷载参数λq的增大而增大;对比土体的界面参数和荷载参数对土体大变形固结的影响可知,界面参数对土体固结的影响更大。

关键词：连续排水边界大变形固结界面参数荷载参数解析解

Electrodeposited Sulfur and CoxS Electrocatalyst on Buckypaper as High-Performance Cathode for Li-S Batteries

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Nano-Micro Letters 2020年第10期12卷 263-275页

作者： Yi zhan.Andrea Buffa Linghui Yu Zhichuan JXu Daniel Mandler School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Institute of Chemistry The Hebrew University of Jerusalem9190401 JerusalemIsrael Campus for Research Excellence and Technological Enterprise(CREATE) Singapore-HUJ Alliance for Research and Enterprise(SHARE)Singapore 138602Singapore

Lithium-sulfur batteries(LSBs)are considered as the next generation of advanced rechargeable batteries because of their high energy *** this study,sulfur and CoxS electrocatalyst are deposited on carbon nanotube buckypaper(S/CoxS/BP)by a facile electrodeposition method and are used as a binder-free high-performance cathode for *** sulfur is deposited on buckypaper by electrooxidation of a polysulfide solution(-S6^2-).This approach substantially increased the current and time efficiency of sulfur electrochemical deposition on conductive material for LSBs.S/CoxS/BP cathode could deliver an initial discharge capacity as high as 1650 mAh g^-1 at 0.1 C,which is close to the theoretical capacity of *** current rate of 0.5 C,the S/CoxS/BP has a capacity of 1420 mAh g^-1 at the first cycle and 715 mAh g^-1 after 500 cycles with a fading rate of 0.099%per *** high capacity of S/CoxS/BP is attributed to both the homogeneous dispersion of nanosized sulfur within BP and the presence of CoxS *** sodium dodecyl sulfate(SDS)pretreatment of BP renders it polarity to bind polysulfides and thus facilitates the good dispersibility of nanosized sulfur within *** catalyst accelerates the kinetics of polysulfide conversion and reduces the presence of polysulfide in the cathode,which suppresses the polysulfide diffusion to anode,i.e.,the shuttle *** mitigation of the active material loss improves not only the capacity but also the cyclability of S/CoxS/BP.

关键词： Electrodeposition Lithium sulfur batteries Buckypaper Electrocatalysts

Effect of hydration on the surface basicity and catalytic activity of Mg-rare earth mixed oxides for aldol condensation

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Journal of Rare Earths 2018年第4期36卷 359-366页

作者： Zheng Wang Pascal Fongarland Guanzhong Lu Wangcheng zhan.Nadine Essayem Key Laboratory for Advanced Materials and REsearch Institute of Industrial Catalysis School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Institut de REcherches sur la Catalyse et l'Environnement de Lyon(IRceLYON) CNRS-Universite Lyon 12 Avenue Albert Einstein69626 Villeurbanne CedexFrance

Magnesium and rare earth mixed oxides（Mg3 REOx（RE=La, Y. ce）） were prepared and characterized by Xray diffraction（XRD）, N_2 adsorption-desorption, infrared spectra and microcalorimetry of CO_2. The results reveal that the Mg_3 ceO_x catalyst is present in the form of Mg-ce-O solid solution,while the Mg3 LaOx and Mg_3 YO_x catalysts are probably rare earth oxides dispersed on MgO surface. As a result, among the calcined Mg_3 REO_x catalysts, the Mg_3 ceO_x catalyst presents the highest rate constant for acetone aldolization, which is well correlated to its more homogeneous distribution of basic sites. In contrary, the Mg_3 YO_x catalyst exhibit the lowest catalytic activity for acetone aldolization. Upon hydration pre-treatment, the basic properties on the surface of the Mg_3 REO_x catalysts were changed markedly. The Mg_3 YO_x catalyst after hydration treatment shows the highest amount of basic sites on catalyst surface, and then exhibits the highest activity among the hydrated Mg_3 REO_x catalysts. These results make it possible to fine-tune basic sites for acetone aldolization.

关键词： Mg-rare earth mixed oxide Hydration treatment Water tolerance Aldol condensation Solid base catalyst Rare earths

基于毛细管连通率和水力迂曲度的碳酸盐岩渗透率分形模型

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工程科学与技术 2024年第2期56卷 236-245页

作者：魏源盛金昌郑惠峰詹美礼黄泰仁王惠民刘星星罗玉龙黄河勘测规划设计研究院有限公司博士后科研工作站河南郑州450003 水利部黄河流域水治理与水安全重点实验室(筹) 河南郑州450003 河海大学水利水电学院江苏南京210098 中国电建集团华东勘测设计研究院有限公司浙江杭州311122

碳酸盐岩非匀质性强,孔隙结构呈现出连通率低、迂曲度高的典型特征。而以往的渗透率分形模型假设岩石孔隙由相互不干扰的毛细管束组成,忽略了复杂成岩过程中胶结作用导致的毛细管连通性降低和迂曲度增大的情况,难以准确评估低渗碳酸盐... 详细信息

碳酸盐岩非匀质性强,孔隙结构呈现出连通率低、迂曲度高的典型特征。而以往的渗透率分形模型假设岩石孔隙由相互不干扰的毛细管束组成,忽略了复杂成岩过程中胶结作用导致的毛细管连通性降低和迂曲度增大的情况,难以准确评估低渗碳酸盐岩的渗透特性。针对渗透率被高估的研究现状,利用满足阿波罗填充的等径颗粒致密堆积分形毛细管束模型,提出了毛细管连通率表征进出口毛细管过流面积损失,并在流体渗透路径几何迂曲度与孔隙度关系的基础上,引入曲折度指数来反映岩石的实际水力迂曲度,最终建立基于连通率、水力迂曲度的碳酸盐岩渗透率分形模型。考虑曲折度指数的水力迂曲度计算值与试验压汞法测定值更为一致;基于毛细管连通率、实际水力迂曲度的碳酸盐岩渗透率分形模型计算结果与细观测定及渗透试验数据吻合较好,表明提出的碳酸盐岩渗透率分形模型能够更好地预测碳酸盐岩真实渗透率。参数敏感性分析发现,孔隙度相同,粒径不同的碳酸盐岩,渗透率均随着孔径增加而增加;同时相同粒径岩石,渗透率随着孔隙度的增大而增大,但由于孔隙面积最小/最大值、孔隙面积分形维数均与孔隙度相关,渗透率与孔隙度的关系不是单纯的线性关系,渗透率随着孔隙度增大的增幅逐渐减小、敏感性逐渐降低。

关键词：阿波罗填充水力迂曲度毛细管连通率渗透率分形

富含半胱氨酸和甘氨酸蛋白2在神经母细胞瘤恶性进展中的功能和机制

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北京大学学报（医学版） 2024年第3期56卷 495-504页

作者：张瑶郭金鑫战世佳洪恩宇杨慧贾安娜常艳郭永丽张璇国家儿童医学中心首都医科大学附属北京儿童医院儿科重大疾病研究教育部重点实验室北京市儿科研究所儿童耳鼻咽喉头颈外科疾病北京市重点实验室北京100045

目的:探究富含半胱氨酸和甘氨酸蛋白2(cysteine and glycine-rich protein 2,CSRP2)在神经母细胞瘤(neuroblastoma,NB)恶性进展中的功能和作用机制。方法:利用R2数据库分析NB临床样本中CSRP2基因的mRNA水平与NB患儿临床预后的相关性;在N... 详细信息

目的:探究富含半胱氨酸和甘氨酸蛋白2(cysteine and glycine-rich protein 2,CSRP2)在神经母细胞瘤(neuroblastoma,NB)恶性进展中的功能和作用机制。方法:利用R2数据库分析NB临床样本中CSRP2基因的mRNA水平与NB患儿临床预后的相关性;在NB细胞系SK-N-BE(2)和SH-SY5Y中利用靶向小干扰RNA(small interfering RNA,siRNA)干扰CSRP2的表达或利用质粒转染过表达CSRP2;通过结晶紫染色和实时无标记动态细胞分析技术观察NB细胞的增殖情况;采用克隆形成方法观察NB细胞长时间的克隆形成能力;利用免疫荧光实验检测细胞增殖标记物Ki-67的水平;利用碘化丙啶(propidium iodide,PI)染色流式细胞术分析细胞周期比例,Annexin V/7AAD染色分析细胞凋亡比例;采用划痕实验观察细胞的迁移能力;利用Western blot或实时荧光定量PCR(quantitative real-time PCR,RT-qPCR)检测NB原发肿瘤组织和细胞系中蛋白和基因的表达水平。结果:NB临床数据库中,国际神经母细胞瘤分期(international neuroblastoma staging system,INSS)为高危险度3/4期的NB组织中CSRP2的mRNA水平显著高于低危险度的1/2期,且高表达水平组NB患儿的生存期显著低于低表达组;Western blot结果显示,CSRP2在3/4期NB组织中的蛋白水平显著高于1/2期。NB细胞中敲低CSRP2,细胞的活力减弱、增殖能力降低;NB细胞中过表达CSRP2促进细胞增殖;敲低CSRP2后,sub-G1、G0/G1和S期细胞的比例增加,Annexin V阳性细胞的比例增多;敲低CSRP2的NB细胞的划痕愈合率显著小于对照组。机制研究发现,敲低CSRP2后细胞增殖标记分子Ki-67和细胞外信号调节激酶1/2(extracellular signal-regulated kinases 1/2,ERK1/2)磷酸化水平显著低于对照组。结论:CSRP2在高危险度3/4期NB组织中高表达,表达水平与NB患儿生存期呈负相关;CSRP2通过促进ERK1/2活化,促进NB细胞的增殖和迁移,抑制细胞凋亡,表明CSRP2通过激活ERK1/2促进NB进展,为高危NB的靶向治疗提供了潜在的靶点。

关键词：富含半胱氨酸和甘氨酸蛋白2 神经母细胞瘤细胞增殖细胞迁移细胞外信号调节激酶1/2

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Effects of elevated ozone on growth and yield of field-grown rice in Yangtze River Delta,China

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Journal of Environmental Sciences 2008年第3期20卷 320-325页

作者： CHEN zhan.WANG Xiaoke FENG Zhaozhong ZHENG Feixiang DUAN Xiaonan YANG Wenrui Research center for Eco-Environmental Sciences Chinese Academy of Scienees Beijing 100085 China

With rapid industrialization and urbanization in the Yangtze Delta, China, the tropospheric ozone concentration has increased to levels that induce crop yield loss. Rice, a widely grown crop in China, was investigated in field-established, open-top chambers. Four treatments were used： charcoal-filtered air （CF）, non-charcoal-filtered air （NF）, and charcoal-filtered air with two levels of additional ozone （O3-1 and O3-2）. The AOT40s （accumulated hourly mean ozone concentration above 40 ppbv） were 0, 0.91, 23.24, and 39.28 ppmv.h for treatment of ce NF, O3-1, and O3-2, respectively. The rice height and biomass were reduced in the elevated ozone concentration. Less organic matter partitioning to roots under the elevated ozone significantly decreased rice root activity. The yield loss was 14.3% and 20.2% under O3-1 and O3-2 exposure, respectively. This was largely caused by a reduction in grain weight per panicle.

关键词： ozone rice growth yield Yangtze Delta

Effects of synthesis methods on the performance of Pt + Rh/ce_(0.6)Zr_(0.4)O_2 three-way catalysts

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Journal of Environmental Sciences 2014年第3期26卷 683-693页

作者： Zongcheng zhan.Liyun Song Xiaojun Liu Jiao Jiao Jinzhou Li Hong He Laboratory of Catalysis Chemistry and Nano-Science Department of Chemistry and Chemical Engineering College of Environmental and Energy Engineering Beijing University of Technology

The 0.7 wt% Pt ＋ 0.3 wt% Rh/ce0.6Zr0.4O2 catalysts were fabricated via different methods, including ultrasonic-assisted membrane reduction （UAMR） co-precipitation, UAMR separation precipitation, co-impregnation, and sequential impregnation. The catalysts were physico-chemically characterized by N2 adsorption, XRD, TEM, and Hz-TPR techniques, and evaluated for three-way catalytic activities with simulated automobile exhaust. UAMR co-precipitation- and UAMR separation precipitation- prepared catalysts exhibited a high surface area and metal dispersion, wide λ window and excellent conversion for NOx reduction under lean conditions. Both fresh and aged catalysts from UAMR- precipitation showed the high surface areas of ca. 60-67 m^2/g and 18-22 m^2/g, respectively, high metal dispersion of 41%-55%, and small active particle diameters of 2.1-2.7 nm. When these catalysts were aged, the catalysts prepared by the UAMR method exhibited a wider working window （△λ = 0.284--0.287） than impregnated ones （△λ = 0.065-0.115） as well as excellent three-way catalytic performance, and showed lower/so （169℃） and T90 （195℃） for NO reduction than the aged catalysts from impregnation processes, which were at 265 and 309℃, respectively. This implied that the UAMR-separation precipitation has important potential for industrial applications to improve catalytic performance and thermal stability. The fresh and aged 0.7 wt% Pt ＋ 0.3 wt% Rh/ce0.6Zr0.4O2 catalysts prepared by the UAMR-separation precipitation method exhibited better catalytic performance than the corresponding catalysts prepared by conventional impregnation routes.

关键词： UAMRthree way catalyst Pt and Rh nanoparticles precipitation thermal stability

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基于以太网技术的光电信号检测系统

化工自动化及仪表 2024年第4期51卷 671-680页

作者：于波沈佳怡战强吕秀丽东北石油大学物理与电子工程学院

针对光信号检测传输速率低、传输距离短及检测成本高等问题,结合EP4ce115F29C7N型芯片,设计基于以太网的光电信号检测系统。该系统将光电信号采集模块采集到的信号通过AD7606采样并进行预处理后存储到片外SDRAM,同时在UDP/IP协议基础上... 详细信息

针对光信号检测传输速率低、传输距离短及检测成本高等问题,结合EP4ce115F29C7N型芯片,设计基于以太网的光电信号检测系统。该系统将光电信号采集模块采集到的信号通过AD7606采样并进行预处理后存储到片外SDRAM,同时在UDP/IP协议基础上设计以太网通信模块,将数据通过数据包的方式发送到上位机,并基于LabVIEW设计光信号采集监控系统,实现对上传数据的滤波和实时检测。通过对比输入信号和LabVIEW监控系统显示信号的一致性,验证了系统的正确性。实验结果表明:该系统可以减少光检测信号远距离传输的数据损耗,提高光电信号的检测效率,有较好的实时性和可读性,且程序移植灵活,节约并缩短了光电检测成本和系统开发时间。

关键词：光电检测 FPGA 以太网 UDP/IP LabVIEW

Bionic microchannels for step lifting transpiration

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International Journal of Extreme Manufacturing 2023年第2期5卷 244-252页

作者： Zhaolong Wang Qiu Yin Ziheng zhan.Wenhao Li Mingzhu Xie Huigao Duan Ping Cheng ce zhan. Yongping Chen Zhichao Dong Interdisciplinary Research center of Low-carbon Technology and Equipment College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082People’s Republic of China MOE Key Laboratory for Power Machinery and Engineering School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Qian Xuesen Laboratory of Space Technology China Academy of Space Technology(CAST)Beijing 100094People’s Republic of China Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Environmental Science and EngineeringSuzhou University of Science and TechnologySuzhouJiangsu 215009People’s Republic of China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096People’s Republic of China Chinese Academy of Sciences Key Laboratory of Bio-inspired Materials and Interface Sciences Technical Institute of Physics and ChemistryChinese Academy of Sciences100190 BeijingPeople’s Republic of China

Those various cross-sectional vessels in trees transfer water to as high as 100 meters,but the traditional fabrication methods limit the manufacturing of those vessels,resulting in the non-availability of those bionic ***,we fabricate those bionic microchannels with various cross-sections by employing projection micro-stereolithography(PμSL)based 3D printing *** circumradius of bionic microchannels(pentagonal,square,triangle,and five-pointed star)can be as small as 100μm with precisely fabricated sharp ***'s more,those bionic microchannels demonstrate marvelous microfluidic performance with strong precursor effects enabled by their sharp *** significantly,those special properties of our bionic microchannels enable them outstanding step lifting performance to transport water to tens of millimeters,though the water can only be transported to at most 20 mm for a single bionic *** mimicked transpiration based on the step lifting of water from bionic microchannels is also *** precisely fabricated,low-cost,various cross-sectional bionic microchannels promise applications as microfluidic chips,long-distance unpowered water transportation,step lifting,mimicked transpiration,and so on.

关键词： bionic microchannel microfluidics water transportation step lifting 3D printing