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Modification of YSZ fiber composites by Al_(2)TiO_(5) fibers for high thermal shock resistance

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Journal of Advanced Ceramics 2022年第6期11卷 922-934页

作者： Wei LIU Yongshuai XIE Zhezhe DENG Ying PENG Jianhong DONG Ze ZHU Dehua MA Luyi ZHU guanghui zhang Xinqiang WANG State Key Laboratory of Crystal Materials School of Crystal MaterialsShandong UniversityJinan 250100China

Yttria-stabilized zirconia(YSZ)fiber composites are highly efficient thermal insulating materials;however,the poor thermal shock resistance limits their versatile *** the present study,YSZ fiber was mixed directly with Al_(2)TiO_(5)fiber,which had an extremely low thermal expansion coefficient,to prepare YSZ–Al_(2)TiO_(5)(ZAT)fiber composites by compression molding and heat *** minimum thermal expansion coefficient of the prepared ZAT fiber composites was measured to be 7.74×10^(−6)K^(−1),which was 26%lower than that of the YSZ fiber composites(10.42×10^(−6)K^(−1)).It was shown that the prepared ZAT fiber composites maintain the integrity after undergoing 51 thermal shock cycles between 1100℃and room ***,YSZ fiber composites burst immediately after only one thermal shock cycle under the same *** addition,the ZAT fiber composites also exhibit considerable mechanical and thermal insulating performance.

关键词： Al_(2)TiO_(5)fibers YSZ-Al_(2)TiO_(5)fiber composites thermal expansion thermal shock resistance thermal insulating

距今4000年前后黄土高原西北边缘的生业经济:稳定同位素的证据

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文物季刊 2024年第2期 131-144页

作者：侯亮亮杨柳红王彬馨贾尧张光辉山西大学考古文博学院山西省古建筑与彩塑壁画保护研究院山西省考古研究院

为揭示距今4000年前后黄土高原西北边缘传统粟黍农业与牛羊饲喂等新生产力要素间的关系,本文以碧村遗址3例人骨和53例动物骨骼为研究对象,运用碳氮稳定同位素分析的方法,还原了他们的食谱及家畜饲养方式。结果显示,部分先民(-7.3‰,8.8... 详细信息

为揭示距今4000年前后黄土高原西北边缘传统粟黍农业与牛羊饲喂等新生产力要素间的关系,本文以碧村遗址3例人骨和53例动物骨骼为研究对象,运用碳氮稳定同位素分析的方法,还原了他们的食谱及家畜饲养方式。结果显示,部分先民(-7.3‰,8.8‰,n=1)、家猪(-7.9‰±1.7‰,5.9‰±0.7‰,n=15)和家犬(-7.8‰±0.3‰,7.5‰±0.4‰,n=2)主要以粟黍类食物为生;其余人(-13.4‰±0.2‰,6.7‰±1.0‰,n=2)、牛(-13.9‰±1.3‰,5.6‰±0.6‰,n=11)和羊(-16.0‰±1.1‰,5.3‰±0.7‰,n=15)则以C3/C4类混合食物为生。研究显示,牛和羊既在野生系统中生存,又食用一定量粟黍类食物。当地众多深沟大壑并不适合粟黍农业发展,但却适宜放牧牛羊,这无疑能增加物资产出。同时,外来牛和羊没有侵占传统家猪的饲喂规模,反而优化了粟黍资源的利用。

关键词：碧村遗址距今4000年前后碳氮稳定同位素粟黍农业牛羊饲喂

Anti-windup design for the controllers of integrating processes with long delay

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Journal of Systems Engineering and Electronics 2007年第2期18卷 297-303页

作者： zhang guanghui Shao Huihe Inst. of Automation Shanghai Jiaotong Univ. Shanghai 200030 P. R. China

For several superior controllers of the first-order integrating processes with long delay, the windup problems are analyzed in detail when the control signal saturates. The results show that these controllers have similar characteristics about the process input limitation. And then, a simple and effective anti-windup scheme, without an additional parameter, is designed for these controllers. Simulations run with three main controllers, and the results illustrate that the proposed method may achieve good performance under the nominal and model uncertainty cases.

关键词： Anti-windup Integrating processes Smith predictor Time-delay system.

Designing unimolecular photoinitiator by installing NHPI esters along the TX backbone for acrylate photopolymerization and their applications in coatings and 3D printing

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Chinese Chemical Letters 2024年第7期35卷 417-421页

作者： Yi Zhu Jingyan zhang Yuchao zhang Ying Chen guanghui An Ren Liu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China International Research Center for Photoresponsive Molecules and Materials Jiangnan UniversityWuxi 214122China School of Chemistry and Materials Science Heilongjiang UniversityHarbin 150080China Scientific Experiment Center Hangzhou Institute of Medicine(HIM)Chinese Academy of SciencesHangzhou 310022China

Developing efficient and long wavelength sensitive unimolecular photoinitiators(PIs)is still facing a great *** this work,a series of thioxanthone-based N-hydroxyphthalimide esters(TX-NHPIEs)were synthesized by installing NHPIEs along the TX backbone and *** investigated TX-NHPIEs have a 60 nm redshift and demonstrate sterling initiating efficiency for free radical photopolymerization(FRP)under LED@450 nm light irradiation compared with the commercialized isopropylthioxanthone(ITX).Real-time1Hnuclear magnetic resonance(1H NMR),electron spin resonance(ESR),decarboxylation and gas chromatograph-mass spectrometer(GC–MS)experiments and density functional theory(DFT)reveal that TX-NHPIEs can generate one alkyl radical and one N-centered iminyl radical,which can initiate FRP directly and indirectly,*** other words,TX-NHPIEs absorb one photon and can generate two active radicals,which break through the limitations of common ***-NHPIE-Cpe demonstrates the highest initiating efficiency,and its application in coatings and 3D printing was also studied,indicating TX-NHPIEs have broad potential applications in photopolymerization processes.

关键词： Photopolymerization Photoinitiator Energy transfer Thioxanthone N-Hydroxyphthalimide ester

Mass transfer enhancement and hydrodynamic performance with wire mesh coupling solid particles in bubble column reactor

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Chinese Journal of Chemical Engineering 2024年第3期67卷 195-205页

作者： Chuanjun Di Jipeng Dong Fei Gao guanghui Chen Pan zhang Jianlong Li Key Laboratory of Multiphase Flow Reaction and Separation Engineering of Shandong Province College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266043China

It is of vital significance to investigate mass transfer enhancements for chemical engineering *** work focuses on investigating the coupling influence of embedding wire mesh and adding solid particles on bubble motion and gas-liquid mass transfer process in a bubble *** image velocimetry(PIV)technology was employed to analyze the flow field and bubble motion behavior,and dynamic oxygen absorption technology was used to measure the gas-liquid volumetric mass transfer coefficient(kLa).The effect of embedding wire mesh,adding solid particles,and wire mesh coupling solid particles on the flow characteristic and kLa were analyzed and *** results show that the gas-liquid interface area increases by 33%-72%when using the wire mesh coupling solid particles strategy compared to the gas-liquid two-phase flow,which is superior to the other two strengthening *** with the system without reinforcement,kLa in the bubble column increased by 0.5-1.8 times with wire mesh coupling solid particles method,which is higher than the sum of kLa increases with inserting wire mesh and adding particles,and the coupling reinforcement mechanism for affecting gas-liquid mass transfer process was discussed to provide a new idea for enhancing gas-liquid mass transfer.

关键词： Fluid mechanics Bubble Mass transfer Wire mesh coupling solid particles Particle image velocimetry Hydrodynamics

不同频度和强度的干湿循环对花岗岩红壤固结强度的影响

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中国水土保持科学 2024年第3期22卷 28-35页

作者：任秋菊孙艺函魏玉杰陈新王佳鑫刘凌志张光辉蔡崇法华中农业大学资源与环境学院武汉430070 中国电建集团华东勘测设计研究院有限公司杭州311100

南方频繁干湿交替环境是影响土体结构强度演化的重要因素。为系统探究干湿循环频度和强度对赣州花岗岩红壤固结强度的影响,本研究通过进行不同强度和频度干湿循环条件下的快速固结试验,确定干湿循环效应对固结强度变化的影响机制。结果... 详细信息

南方频繁干湿交替环境是影响土体结构强度演化的重要因素。为系统探究干湿循环频度和强度对赣州花岗岩红壤固结强度的影响,本研究通过进行不同强度和频度干湿循环条件下的快速固结试验,确定干湿循环效应对固结强度变化的影响机制。结果表明:1)孔隙比随着荷载压力的增大呈现先快速减小后趋于平稳趋势,干湿循环加剧花岗岩红壤的压缩变形;2)土壤瞬时沉降量和主固结沉降量均随着干湿循环频度和强度作用增强而逐渐增加;3)花岗岩红壤干湿循环后的压缩系数在0.8~1.0之间,呈现高压缩性,且随着频度的增加压缩系数逐渐增大,7次循环后缓慢增加并趋于稳定;干湿循环频度和强度增加条件下固结系数均呈现连续下降趋势,使土体强度降低;4)干湿循环频度对固结系数和压缩系数变化作用最为显著(F=4102.71,P<0.001;F=508.40,P<0.001)。研究结果说明季节性降雨干旱引发的干湿循环效应显著影响土体的固结强度,加剧岩土体失稳崩塌的风险。

关键词：花岗岩红壤干湿循环频度干湿循环强度固结特性土壤侵蚀

Durable natural killer cell response after three doses of SARS-CoV-2 inactivated vaccine in HIV-infected individuals

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Chinese Medical Journal 2023年第24期136卷 2948-2959页

作者： Xiaodong Yang Xiuwen Wang Xin zhang Haifeng Ding Hu Wang Tao Huang guanghui zhang Junyi Duan Wei Xia Bin Su Cong Jin Hao Wu Tong zhang Beijing Key Laboratory for HIV/AIDS Research Sino-French Joint Laboratory for Research on Humoral Immune Response to HIV InfectionClinical and Research Center for Infectious DiseasesBeijing Youan HospitalCapital Medical UniversityBeijing 100069China National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Tian Yuan Studio Beijing Youan HospitalCapital Medical UniversityBeijing 100069China

Background:Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)vaccine can induce a potent cellular and humoral immune response to protect against SARS-CoV-2 ***,it was unknown whether SARS-CoV-2 vaccination can induce effective natural killer(NK)cell response in people living with human immunodeficiency virus(PLWH)and healthy ***:Forty-seven PLWH and thirty healthy controls(HCs)inoculated with SARS-CoV-2 inactivated vaccine were enrolled from Beijing Youan Hospital in this *** effect of SARS-CoV-2 vaccine on NK cell frequency,phenotype,and function in PLWH and HCs was evaluated by flow cytometry,and the response of NK cells to SARS-CoV-2 Omicron Spike(SARS-2-OS)protein stimulation was also ***:SARS-CoV-2 vaccine inoculation elicited activation and degranulation of NK cells in PLWH,which peaked at 2 weeks and then decreased to a minimum at 12 weeks after the third dose of ***,in vitro stimulation of the corresponding peripheral blood monocular cells from PLWH with SARS-2-OS protein did not upregulate the expression of the aforementioned ***,the frequencies of NK cells expressing the activation markers CD25 and CD69 in PLWH were significantly lower than those in HCs at 0,4 and 12 weeks,but the percentage of CD16^(+)NK cells in PLWH was significantly higher than that in HCs at 2,4 and 12 weeks after the third dose of ***,the frequency of CD16^(+)NK cells was significantly negatively correlated with the proportion of CD107a^(+)NK cells in PLWH at each time point after the third ***,this phenomenon was also observed in HCs at 0,2,and 4 weeks after the third ***,regardless of whether NK cells were stimulated with SARS-2-OS or not,we did not observe any differences in the expression of NK cell degranulation markers between PLWH and ***:SARS-CoV-2 vaccine elicited activation and degranulation of NK cells,indicating that the inoculation of

关键词： HIV SARS-CoV-2 inactivated vaccine COVID-19 Omicron variant NK cell response Immunologic memory

A comprehensive review on coupled processes and mechanisms of soil-vegetation-hydrology, and recent research advances

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Science China Earth Sciences 2022年第11期65卷 2083-2114页

作者： Zhongkai LI Xiaoyan LI Sha ZHOU Xiaofan YANG Yongshuo FU Chiyuan MIAO Shuai WANG guanghui zhang Xiuchen WU Chao YANG Yuanhong DENG State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Natural Resources Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXining 810016China School of Geographical Sciences Qinghai Normal UniversityXining 810016China College of Water Sciences Beijing Normal UniversityBeijing 100875China

Research on the coupling of soil,vegetation,and hydrological processes is not only a research hotspot in disciplines such as pedology,ecohydrology and Earth system science but also important for achieving sustainable ***,scientists from different disciplines usually study the coupling mechanism of soil-vegetation-hydrological processes at very different space and time scales,and the mechanistic connections between different scales are quite *** article reviewed research advances in coupled soil-vegetation-hydrological processes at different spatial scales—from leaf stomata to watershed and regional scales—and summarized the spatial upscaling methods and modeling approaches of coupled soil-vegetationhydrological *** identify and summarize the following coupling processes:(1)carbon-water exchange in leaf stomata and root-soil interface;(2)changes in soil aggregates and profile hydraulic properties caused by plant roots and water movement;(3)precipitation and soil moisture redistribution by plant canopy and root;(4)interactions between vegetation patches and local hydrological process;(5)links between plant community succession and soil development;and(6)links between watershed/regional water budget and vegetation phenology and ***,the limitations and knowledge gaps in the observations,mechanisms,scaling methods,and modeling approaches of coupled soil-vegetation-hydrological processes were *** achieve a deep integration of various coupling processes across different spatiotemporal scales,future work should strengthen multiscale,multifactor and multiprocess soil-vegetation-hydrology coupling observations and mechanism studies,develop new scaling methods,identify different feedback pathways,and take time-variable plant behavior and soil hydraulic properties into account during modeling.

关键词： Ecohydrological process Soil process Plant-soil feedback Modeling approaches Scaling method

Numerical Investigation of Aluminum Foam Shield Based on Fractal Theory and Node-separation FEM

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Chinese Journal of Aeronautics 2011年第6期24卷 734-740页

作者： zhang Xiaotian JIA guanghui HUANG Hai School of Astronautics Beihang University Beijing 100191 China

Fractal feature of aluminum foam （Al-foam） section is analyzed with digital image processing technique, and fractal dimension of Al-foam is evaluated with logarithmic linear regression method. Sierpinski carpet can be used to model Al-foam section. Al-foam with different fractal dimensions and relative density can be obtained by adjusting iteration times and division parameters. Sierpinski sponge is extended from Sierpinski carpet and used to model 3D Al-foam bumper. Node-separation Lagrangian finite element method （FEM） is introduced to simulate the hypervelocity impact （HVI） process. The modeling and simulation method is calibrated by the comparison of numerical results and experimental data. Ballistic limit curves of Al-foam and aluminum alloy bumper with the same areal density are obtained by simulations. The results show that the protection pertbrmance of Al-foam bumner is much better than aluminum alloy bumper. Al-foam is well suited for spacecraft shield application.

关键词： aluminum foam simulation fractal hypervelocity impact FEM