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Tracking Performance of Electric Power Steering System Based on the Mixed H_2/H_∞ Strategy 被引量:10
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作者 ZHAO Wanzhong SHI Guobiao +1 位作者 LIN Yi NIE Hong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第4期584-590,共7页
The tracking performance of motor current is an important factor that affects the assistance torque of electric power steering (EPS) system. Bad tracking performance will cause assistant torque delay, and make road ... The tracking performance of motor current is an important factor that affects the assistance torque of electric power steering (EPS) system. Bad tracking performance will cause assistant torque delay, and make road feeling bad, and is influenced by the input steering torque and system measuring noise. However the existing methods have some shortages on system's robust dynamic performance and robust stability. The mixed H2/H∞ strategy for recirculating ball-type EPS system in a pure electric bus is proposed, and vehicle dynamic model of the system is established. Due to the existence of system model uncertainty, disturbance signals, sensor noises and the demand of system dynamic performance, the indexes of robust performance and road feeling for drivers are defined as the appraisal control objectives. The H∞ method is introduced to design the H∞ controller, and the H2 method is applied to optimize the H∞ controller, thus the mixed H2/H∞ controller is designed. The response of EPS system to the motor current command with amplitude of 20 A, the road disturbance with amplitude of 500 N and the sensor random noise with the amplitude of 1 A is simulated. The simulation results show that the recirculating ball-type EPS system with the mixed H2/H∞ controller can attenuate the random noises and disturbances and track the boost curve well, so the mixed H2/H∞ controller can improve the system's robust performance and dynamic performance. For the purpose of verifying the performance of the designed control strategy, the motor current tracking performance ground tests are conducted with step response input of the steering wheel, double-lane steering test and lemniscate steering test, respectively. The tests show that the mixed H2/H∞ controller for the recirculating ball-type EPS system of pure electric bus is feasible. The designed controller can solve the robust performance and robust stability of the system, thus improve the tracking performance of the EPS system and provide satisfied road feeling for the drivers. 展开更多
关键词 recirculating ball-type electrical power steering (EPS) system tracking performance mixed h2/h∞
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Reliable Controller Design with Mixed H_2/H_∞ Performance for Descriptor Systems 被引量:3
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作者 陈跃鹏 张庆灵 翟丁 《自动化学报》 EI CSCD 北大核心 2005年第2期262-266,共5页
The design problem of a reliable observer-based controller with mixed H2/H∞ performance for descriptor systems is discussed using linear matrix inequality (LMI) approach. First, the design problems of H2 and Ho contr... The design problem of a reliable observer-based controller with mixed H2/H∞ performance for descriptor systems is discussed using linear matrix inequality (LMI) approach. First, the design problems of H2 and Ho controllers are discussed, respectively. Secondly, when there are partial actuator faults for the descriptor system, controllers with H2 and H∞ performance are designed, respectively. Finally, a numerical example is given to illustrate the design procedures and their effectiveness. 展开更多
关键词 广义系统 混合h2/h∞性能 可靠控制器 描述符系统 线性矩阵不等式
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Parameters Optimization and Performance Evaluation of the Tuned Inerter Damper for the Seismic Protection of Adjacent Building Structures
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作者 Xiaofang Kang Jian Wu +1 位作者 Xinqi Wang Shancheng Lei 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期551-593,共43页
In order to improve the seismic performance of adjacent buildings,two types of tuned inerter damper(TID)damping systems for adjacent buildings are proposed,which are composed of springs,inerter devices and dampers in ... In order to improve the seismic performance of adjacent buildings,two types of tuned inerter damper(TID)damping systems for adjacent buildings are proposed,which are composed of springs,inerter devices and dampers in serial or in parallel.The dynamic equations of TID adjacent building damping systems were derived,and the H2 norm criterion was used to optimize and adjust them,so that the system had the optimum damping performance under white noise random excitation.Taking TID frequency ratio and damping ratio as optimization parameters,the optimum analytical solutions of the displacement frequency response of the undamped structure under white noise excitation were obtained.The results showed that compared with the classic TMD,TID could obtain a better damping effect in the adjacent buildings.Comparing the TIDs composed of serial or parallel,it was found that the parallel TIDs had more significant advantages in controlling the peak displacement frequency response,while the H2 norm of the displacement frequency response of the damping system under the coupling of serial TID was smaller.Taking the adjacent building composed of two ten-story frame structures as an example,the displacement and energy collection time history analysis of the adjacent building coupled with the optimum design parameter TIDs were carried out.It was found that TID had a better damping effect in the full-time range compared with the classic TMD.This paper also studied the potential power of TID in adjacent buildings,which can be converted into available power resources during earthquakes. 展开更多
关键词 Adjacent buildings tuned inerter damper(TID) h2 norm optimization vibration control energy harvesting
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宽负荷下切圆燃煤锅炉H_(2)S分布特性的数值模拟 被引量:1
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作者 邓磊 袁茂博 +3 位作者 杨家辉 韩磊 姜家豪 车得福 《煤炭学报》 EI CAS CSCD 北大核心 2024年第6期2887-2895,共9页
锅炉采用空气分级燃烧降低NO_(x)排放的同时也提高了主燃区H_(2)S体积分数。炉墙壁面过高的H_(2)S体积分数是加剧水冷壁高温腐蚀的重要因素。为保障新能源并网发电,大型燃煤机组灵活调峰的需求增加,不同负荷下的水冷壁近壁面H_(2)S分布... 锅炉采用空气分级燃烧降低NO_(x)排放的同时也提高了主燃区H_(2)S体积分数。炉墙壁面过高的H_(2)S体积分数是加剧水冷壁高温腐蚀的重要因素。为保障新能源并网发电,大型燃煤机组灵活调峰的需求增加,不同负荷下的水冷壁近壁面H_(2)S分布特性值得关注。通过正交试验分析了切圆燃煤锅炉运行参数对水冷壁近壁面H_(2)S体积分数分布的影响。选取一台超临界600 MW切圆燃煤锅炉建立数值模型,设计L_(16)(4^(5))正交工况,覆盖100%BMCR、75%THA,50%THA以及35%BMCR四种负荷。建立了自定义SO_(x)生成模型以确定燃料硫的析出和转化路径,模型包含多表面反应子模型以描述焦炭与O_(2)/CO_(2)/H_(2)O等3种气体的异相反应,并确定焦炭气化反应消耗量占总消耗量的比例,进而对炉膛H_(2)S空间分布进行了模拟计算。研究表明,近壁面高体积分数H_(2)S区域主要位于投运燃烧器层中最下层燃烧器以下以及最上层燃烧器以上至SOFA层之间,烟气切圆沿炉膛高度增加逐渐增大是造成后一区域H_(2)S体积分数较高的重要原因。35%BMCR负荷下水冷壁重点区域的H_(2)S平均体积分数为364μL/L,明显低于其他负荷。锅炉运行参数对重点区域H_(2)S体积分数影响程度的排序为:锅炉负荷>一次风率>主燃区空气过量系数>假想切圆直径>燃烧器竖直摆角。 展开更多
关键词 切圆燃煤锅炉 宽负荷 h2S分布 正交分析 数值模拟
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基于化学发光酶免疫分析法检测花生过敏原Ara h 2
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作者 王耀 郭开通 +7 位作者 王成宾 宋乾召 李才云 葛梦鋆 蔡文锦 孙亚宁 邢云瑞 胡骁飞 《食品与发酵工业》 CAS CSCD 北大核心 2024年第20期266-272,共7页
Ara h 2是花生主要过敏原之一,为开发食物中Ara h 2过敏原成分的快速检测方法,减少因误食导致花生过敏事件的发生,该研究采用鼠源单克隆抗体作为捕获抗体、兔源多克隆抗体作为检测抗体,通过棋盘法优化抗体工作浓度,建立了一种检测花生... Ara h 2是花生主要过敏原之一,为开发食物中Ara h 2过敏原成分的快速检测方法,减少因误食导致花生过敏事件的发生,该研究采用鼠源单克隆抗体作为捕获抗体、兔源多克隆抗体作为检测抗体,通过棋盘法优化抗体工作浓度,建立了一种检测花生过敏原Ara h 2的间接双抗夹心化学发光酶免疫分析法,并对该方法的灵敏度、准确度、精密度和特异性进行评价。该方法的检出限为1.085 ng/mL,线性范围为3.12~200 ng/mL,添加回收率为78.30%~94.39%,批内和批间变异系数均小于10%,且特异性良好,与其他常见食物过敏原无交叉反应。该方法与相同抗体所建立的间接双抗夹心酶联免疫吸附测定(enzyme-linked immunosorbent assay, ELISA)方法相比,在灵敏度上表现出一定优势。该研究开发的化学发光酶免疫分析法可对花生食品生产过程中和消费前的Ara h 2过敏原成分检测提供可靠的技术支持。 展开更多
关键词 化学发光酶免疫分析 花生过敏原 Ara h 2 检测
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Sulfur-mediated photodeposition synthesis of NiS cocatalyst for boosting H2-evolution performance of g-C3N4 photocatalyst 被引量:8
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作者 Min Wang Jingjing Cheng +3 位作者 Xuefei Wang Xuekun Hong Jiajie Fan Huogen Yu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期37-45,共9页
Modification of nickel sulfide cocatalysts is considered to be a promising approach for efficient enhancement of the photocatalytic hydrogen production performance of g-C3N4.Providing more NiS cocatalyst to function a... Modification of nickel sulfide cocatalysts is considered to be a promising approach for efficient enhancement of the photocatalytic hydrogen production performance of g-C3N4.Providing more NiS cocatalyst to function as active sites of g-C3N4 is still highly desirable.To realize this goal,in this work,a facile sulfur-mediated photodeposition approach was developed.Specifically,photogenerated electrons excited by visible light reduce the S molecules absorbed on g-C3N4 surface to S^2‒,and subsequently NiS cocatalyst is formed in situ on the g-C3N4 surface by a combination of Ni2+and S2‒due to their small solubility product constant(Ksp=3.2×10^‒19).This approach has several advantages.The NiS cocatalyst is clearly in situ deposited on the photogenerated electron transfer sites of g-C3N4,and thus provides more active sites for H2 production.In addition,this method utilizes solar energy with mild reaction conditions at room temperature.Consequently,the synthesized NiS/g-C3N4 photocatalyst achieves excellent hydrogen generation performance with the performance of the optimal sample(244μmol h^‒1 g^‒1)close to that of 1 wt%Pt/g-C3N4(316μmol h^‒1 g^‒1,a well-known excellent photocatalyst).More importantly,the present sulfur-mediated photodeposition route is versatile and facile and can be used to deposit various metal sulfides such as CoSx,CuSx and AgSx on the g-C3N4 surface,and all the resulting metal sulfide-modified g-C3N4 photocatalysts exhibit improved H2-production performance.Our study offers a novel insight for the synthesis of high-efficiency photocatalysts. 展开更多
关键词 g-C3N4 NIS Co-catalyst Sulfur-mediated photodeposition h2 Photocatalysis
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Hydrothermal Synthesis of H_3PW_(12)O_(40)/TiO_2 Nanometer Photocatalyst and Its Catalytic Performance for Methyl Orange 被引量:4
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作者 FENG Chang-gen SHANG Hai-ru 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第3期366-370,共5页
H3PW12O40/TiO2 nanometer photocatalyst was prepared by one step hydrothermal synthesis from H3PW12O40·nH20 and Ti(OBu)4, simultaneously realizing the load and modification of H3PW12O40. The catalyst was charact... H3PW12O40/TiO2 nanometer photocatalyst was prepared by one step hydrothermal synthesis from H3PW12O40·nH20 and Ti(OBu)4, simultaneously realizing the load and modification of H3PW12O40. The catalyst was characterized by Fourier transform infrared spectroscopy(FTIR), powder X-ray diffraction(XRD), nitrogen adsorp- tion-desorption analysis and scanning electron microscopy(SEM). The results show that the catalyst is Keggin struc- ture and crystallized in anatase structure, the diameter and specific area of the prepared catalyst are 3.8 nm and 177.9 m^2/g, respectively, and its dispersity is better. The photocatalytic properties were compared for TiO2H3PW12O40/TiO2 prepared by impregnation and H3PW12O40/TiO2 prepared by hydrothermal method with methyl orange as a probe. The effects of H3PW12O40 loadings, crystallization method, initial pH and concentration of dye solution on the degradation of methyl orange were investigated. 展开更多
关键词 h3PWt2O40/TiO2 hydrothermal synthesis Photocatalytic performance DEGRADATION Methyl orange
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2022-2023年江苏省H3N2流感病毒分子特征及耐药性分析
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作者 邓斐 王慎骄 +3 位作者 余慧燕 祁贤 朱立国 戴启刚 《中国人兽共患病学报》 CAS CSCD 北大核心 2024年第9期848-854,共7页
目的根据2022-2023年江苏省监测年度流感病毒实验室检测结果,对H3N2流感病毒的基因特征和耐药性进行深度分析,评估疫苗和药物的有效性。方法对全省流感网络实验室分离的29株H3N2分离株进行全基因组扩增与测序,构建HA和NA基因进化树。分... 目的根据2022-2023年江苏省监测年度流感病毒实验室检测结果,对H3N2流感病毒的基因特征和耐药性进行深度分析,评估疫苗和药物的有效性。方法对全省流感网络实验室分离的29株H3N2分离株进行全基因组扩增与测序,构建HA和NA基因进化树。分析抗原表位、糖基化位点以及耐药位点的突变特性,并采用荧光发光法对流感病毒神经氨酸酶进行检测。结果江苏省29株H3N2分离株的同源性较高,与国内参考株和2021-2022年度疫苗株位于同一进化分支,与国外参考株和2022-2023年度疫苗株则处于不同进化分支。与2021-2022年度疫苗株A/Cambodia/e0826360/2020相比,江苏省2022-2023年度分离的H3N2流感病毒HA蛋白发生了4个氨基酸位点的替换,NA蛋白发生了2个氨基酸位点的替换,糖基化位点、受体结合位点以及氨基酸残基保守区域未发生改变。IC_(50)结果表明,29株H3N2分离株对奥司他韦和扎那米韦两种抗病毒药物均未产生耐药。结论江苏省2022-2023年监测年度的流感病毒主要为甲型H3N2流感病毒。通过对流感病毒的HA和NA基因变异位点以及耐药性监测,及时了解病毒基因的变异情况,为选择有效的疫苗株提供科学依据,从而有助于预防和控制流感病毒的暴发和流行。 展开更多
关键词 h3N2流感病毒 疫苗 药物 基因特征 进化分析
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Ni nanoparticles as electron-transfer mediators and NiS_x as interfacial active sites for coordinative enhancement of H_2-evolution performance of TiO_2 被引量:7
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作者 Ping Wang Shunqiu Xu +1 位作者 Feng Chen Huogen Yu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第3期343-351,共9页
The development of efficient photocatalytic H2-evolution materials requires both rapid electron transfer and an effective interfacial catalysis reaction for H2 production. In addition to the well-known noble metals, l... The development of efficient photocatalytic H2-evolution materials requires both rapid electron transfer and an effective interfacial catalysis reaction for H2 production. In addition to the well-known noble metals, low-cost and earth-abundant non-noble metals can also act as electron- transfer mediators to modify photocatalysts. However, as almost all non-noble metals lack the interfacial catalytic active sites required for the H2-evolution reaction, the enhancement of the photocatalytic performance is limited. Therefore, the development of new interfacial active sites on metal-modified photocatalysts is of considerable importance. In this study, to enhance the photocatalytic evolution of H2 by Ni-modified TiO2, the formation of NiSx as interfacial active sites was promoted on the surface of Ni nanoparticles. Specifically, the co-modified TiO2/Ni-NiSx photocatalysts were prepared via a two-step process involving the photoinduced deposition of Ni on the TiO2 surface and the subsequent formation of NiSx on the Ni surface by a hydrothermal reaction method. It was found that the TiO2/Ni-NiSx photocatalysts exhibited enhanced photocatalytic H2-evolution activity. In particular, TiO2/Ni-NiSx(30%) showed the highest photocatalytic rate (223.74 μmol h.1), which was greater than those of TiO2, TiO2/Ni, and TiO2/NiSx by factors of 22.2, 8.0, and 2.2, respectively. The improved H2-evolution performance of TiO2/Ni-NiSx could be attributed to the excellent synergistic effect of Ni and NiSx, where Ni nanoparticles function as effective mediators to transfer electrons from the TiO2 surface and NiSx serves as interfacial active sites to capture H+ ions from solution and promote the interfacial H2-evolution reaction. The synergistic effect of the non-noble metal cocatalyst and the interfacial active sites may provide new insights for the design of highly efficient photocatalytic materials. 展开更多
关键词 Titania Electron-transfer mediator Interfacial active site Synergistic effect Photocatalyic h2 evolution
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2-Ethyl-9,10-anthraquinone assisted sol–gel synthesis of Pd/γ-Al2O3 nanorods with enhanced catalytic performance in 2-ethyl-9,10-anthraquinone hydrogenation 被引量:4
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作者 Weiquan Cai Junlin Zhuo +1 位作者 Jimin Fang Zhichao Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1863-1869,共7页
A series of nanorod-like porous Pd/γ-Al2 O3 catalysts with controllable textural properties and enhanced catalytic performance in 2-ethyl-9,10-anthraquinone(eAQ) hydrogenation for H2 O2 preparation were successfully ... A series of nanorod-like porous Pd/γ-Al2 O3 catalysts with controllable textural properties and enhanced catalytic performance in 2-ethyl-9,10-anthraquinone(eAQ) hydrogenation for H2 O2 preparation were successfully prepared via a facile sol-gel method using aluminum isopropoxide as aluminum precursor and eAQ as structure directing agent,sequential calcination and impregnation process with Na2 PdCl4 solution.The physicochemical properties of the catalysts obtained with different addition amounts of eAQ.were comparatively characterized by XRD,TG-DSC,BET,TEM,CO-TPR,H2-TPR and H2-O2 titration.The results show that addition of eAQ can not only effectively control the textural properties(surface area,pore volume and average pore size) of the catalysts,but also lower their reduction temperature of active metal.Importantly,the catalyst obtained with an addition amount of 4 wt% eAQ shows the highest hydrogenation efficiency of 10.28 g·L^-1,which is 37.3% higher than 7.49 g·L^-1 of the catalyst obtained without eAQ. 展开更多
关键词 Catalyst hYDROGENATION Alumina 2-Ethyl-9 10-anthraquinone Structure directing agent h2O2
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Effect of H_2S Flow Rate and Concentration on Performance of H_2S/Air Solid Oxide Fuel Cell 被引量:4
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作者 钟理 张腾云 +3 位作者 陈建军 WEI Guolin LUO Jingli K.Chung 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期306-309,共4页
A solid state H2S/air electrochemical cell having the configuration of H2S, (MoS2+NiS+Ag)/YSZ/Pt, air has been examined with different H2S flow rates and concentrations at atmospheric pressure and 750-850 ℃. Performa... A solid state H2S/air electrochemical cell having the configuration of H2S, (MoS2+NiS+Ag)/YSZ/Pt, air has been examined with different H2S flow rates and concentrations at atmospheric pressure and 750-850 ℃. Performance of the fuel cell was dependent on anode compartment H2S flow rate and concentration. The cell open-circuit voltage increased with increasing H2S flow rate. It was found that increasing both H2S flow rate and H2S concentration improved current-voltage and power density performance. This is resulted from improved gas diffusion in anode and increased concentration of anodic electroactive species. Operation at elevated H2S concentration improved the cell performance at a given gas flow rate. However, as low as 5% H2S in gas mixture can also be utilized as fuel feed to cells. Highest current and power densities, 17500mA·cm-2 and 200mW·cm-2, are obtained with pure H2S flow rate of 50ml·min-1 and air flow rate of 100ml·min-1 at 850℃. 展开更多
关键词 fuel cell performance h2S/air fuel cell solid oxide fuel cell (SOFC)
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ZnxCd1–xS quantum dot with enhanced photocatalytic H2-production performance 被引量:6
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作者 Rongrong Gao Bei Cheng +2 位作者 Jiajie Fan Jiaguo Yu Wingkei Ho 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期15-24,共10页
H2 is an important energy carrier for replacing fossil fuel in the future due to its high energy density and environmental friendliness.As a sustainable H2-generation method,photocatalytic H2 production by water split... H2 is an important energy carrier for replacing fossil fuel in the future due to its high energy density and environmental friendliness.As a sustainable H2-generation method,photocatalytic H2 production by water splitting has attracted much interest.Here,oil-soluble ZnxCd1-xS quantum dot(ZCS QD)with a uniform particle size distribution were prepared by a hot-injection method.However,no photocatalytic H2-production activity was observed for the oil-soluble ZCS QD due to its hydrophobicity.Thus,the oil-soluble ZCS QD was converted into a water-soluble ZCS QD by a ligand-exchange method.The water-soluble ZCS QD exhibited excellent photocatalytic H2-production performance in the presence of glycerin and Ni^2+,with an apparent quantum efficiency of 15.9%under irradiation of 420 nm light.Further,the photocatalytic H2-generation activity of the ZCS QD was~10.7 times higher than that of the ZnxCd1-xS relative samples prepared by the conventional co-precipitation method.This work will inspire the design and fabrication of other semiconductor QD photocatalysts because QD exhibits excellent separation efficiency for photogenerated electron-hole pairs due to its small crystallite size. 展开更多
关键词 ZnxCd1-xS Solid-solution photocatalyst Photocatalytic h2 production Oil-soluble quantum dot Water-oil soluble quantum dot
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广西H9N2亚型禽流感病毒疫苗候选株的筛选
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作者 李孟 谢芝勋 +7 位作者 李丹 徐倩 罗思思 张民秀 谢丽基 黄超 沈前程 黄娇玲 《南方农业学报》 CAS CSCD 北大核心 2024年第1期243-252,共10页
【目的】筛选出免疫原性更优的H9N2亚型禽流感病毒(AIV)疫苗候选株用于新型疫苗研发,为加强对H9N2亚型AIV的防控提供技术支持。【方法】以2000—2020年广西地区分离获得的36株H9N2亚型AIV分离株为试验材料,依据HA基因遗传进化分析选择1... 【目的】筛选出免疫原性更优的H9N2亚型禽流感病毒(AIV)疫苗候选株用于新型疫苗研发,为加强对H9N2亚型AIV的防控提供技术支持。【方法】以2000—2020年广西地区分离获得的36株H9N2亚型AIV分离株为试验材料,依据HA基因遗传进化分析选择12株不同年份、不同地域及不同宿主来源的H9N2亚型AIV代表株,与目前使用的商品化H9亚型AIV疫苗株(SS株)进行交叉血凝抑制试验(HI)及抗原性分析,根据抗原分析结果选择其中具有不同抗原差异的代表株制备油乳剂灭活疫苗,并分别与商品化H9亚型AIV疫苗(SS株)进行交叉免疫保护试验。【结果】在36株H9N2亚型AIV广西分离株中有31株属于Y280-Like(9.4.1),其中26株属于分支I、5株属于分支II,另外5株属于G1-Like(h9.4.1),与我国常用疫苗株分属于不同进化分支。12株H9N2亚型AIV广西代表性分离株灭活后的HA效价≥7 log2,病毒灭活效果良好,可用于制备油乳剂灭活疫苗,且制备的油乳剂灭活疫苗稳定性和安全性良好。根据交互HI抗体滴度计算出各毒株间的抗原相关值(R),结果发现A/chicken/Guangxi/C227/2015(H9N2)株(简称C227株)与其他毒株的抗原性无明显差异,对应的R在0.72~0.93间波动;疫苗交叉保护试验结果也表明,C227株制备的油乳剂灭活疫苗对不同毒株的免疫保护率均高于80%,且免疫保护效果优于A/chicken/Guangxi/CX/2013(H9N2)株(简称CX13株),说明C227株更适合作为H9N2亚型AIV灭活疫苗的候选株。【结论】基于抗原性分析和免疫原性测定筛选出的A/chicken/Guangxi/C227/2015(H9N2)株对广西地区绝大部分H9N2亚型AIV流行株的免疫保护效果良好,可作为疫苗候选株用于研制新型H9N2亚型AIV疫苗。 展开更多
关键词 禽流感病毒(AIV) h9N2亚型 油乳灭活疫苗 抗原相关性 疫苗交叉保护
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Preparation and phase change performance of Na_2HPO_4·12H_2O@poly(lactic acid) capsules for thermal energy storage 被引量:4
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作者 Na Fan Lang Chen +3 位作者 Guoyong Xie Donghong Yin Chak-Tong Au Shuangfeng Yin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第3期695-700,共6页
Micro-encapsulated phase-change materials(micro PCMs) with Na_2 HPO_4·12 H_2 O encapsulated in poly(lactic acid)(PLA) shell were prepared by a solvent evaporation–precipitation method that involves the use of a ... Micro-encapsulated phase-change materials(micro PCMs) with Na_2 HPO_4·12 H_2 O encapsulated in poly(lactic acid)(PLA) shell were prepared by a solvent evaporation–precipitation method that involves the use of a coaxial needle. The effects of PLA concentration, stirring speed, injection rate of core and shell solutions, and polyvinyl alcohol(PVA) concentration on phase change properties were investigated. The thermal properties of microP CMs were characterized by differential scanning calorimetry(DSC). The capsules prepared under the optimal conditions are about 2 mm in diameter and show a latent heat of up to 122.2 J·g^(-1). 展开更多
关键词 Micro-encapsulated PhASE-ChANGE materials Na2hPO4·12h2O Coaxial needle Poly(lactic acid) Thermal energy storage CAPSULE
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长臂猿感染H9N2亚型禽流感病毒病例报告
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作者 冯华娟 吴俊仪 +10 位作者 曹佳媛 尤宗耀 杨露 阙腾程 黄宁 廖小英 农汝 黄泽琳 陆兵兵 李宁莉 莫亚生 《野生动物学报》 北大核心 2024年第4期873-880,共8页
2022年1月,某动物园同一馆舍内饲养的6只长臂猿(Nomascus spp.)先后出现流清涕、咳嗽的症状。采集患病长臂猿鼻拭子共6份,利用高通量测序法对样本进行病原筛查,结果显示:2份样本呈AIV阳性,序列组装结果与H9N2亚型禽流感病毒的相似性最高... 2022年1月,某动物园同一馆舍内饲养的6只长臂猿(Nomascus spp.)先后出现流清涕、咳嗽的症状。采集患病长臂猿鼻拭子共6份,利用高通量测序法对样本进行病原筛查,结果显示:2份样本呈AIV阳性,序列组装结果与H9N2亚型禽流感病毒的相似性最高;采用qPCR法对2份阳性样本进行H1~H16基因和N1~N9基因检测验证,发现5号样本H9 Ct值为31.35、N2 Ct值为36.16,6号样本H9 Ct值为27.46、N2 Ct值为29.57,均为阳性。给予患病长臂猿化痰止咳、消炎和控制继发感染等综合治疗,同时加强饲养环境消毒,患病长臂猿很快康复。 展开更多
关键词 长臂猿 h9N2 禽流感病毒 高通量测序 qPCR
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Fischer-Tropsch Performance of an SiO2-Supported Co-Based Catalyst Prepared by Hydrogen Dielectric-Barrier Discharge Plasma 被引量:3
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作者 付廷俊 黄承都 +1 位作者 吕静 李振花 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第3期232-238,共7页
A silica-supported cobalt catalyst was prepared by hydrogen dielectric-barrier dis- charge (H2-DBD) plasma. Compared to thermal hydrogen reduction, H2-DBD plasma treatment can not only fully decompose the cobalt pre... A silica-supported cobalt catalyst was prepared by hydrogen dielectric-barrier dis- charge (H2-DBD) plasma. Compared to thermal hydrogen reduction, H2-DBD plasma treatment can not only fully decompose the cobalt precursor but also partially reduce the cobalt oxides at lower temperature and with less time. The effect of the discharge atmosphere on the property of the plasma-prepared catalyst and the Fischer-Tropsch synthesis activity was studied. The re- sults indicate that H2-DBD plasma treatment is a promising alternative for preparing Co/SiO2 catalysts from the viewpoint of energy savings and efficiency. 展开更多
关键词 Fischer-Tropsch synthesis COBALT SILICA h2 dielectric-barrier discharge plasma
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H9N2 AIV灭活疫苗免疫SPF鸡攻毒后肺组织免疫相关基因表达变化研究
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作者 李丽 蒋作仪 +4 位作者 李茵婧 常丽凤 辛震东 平继辉 苏娟 《南京农业大学学报》 CAS CSCD 北大核心 2024年第1期18-27,共10页
[目的]本试验旨在探究H9N2亚型禽流感病毒攻击对H9灭活疫苗免疫SPF鸡呼吸系统的影响。[方法]选用36只3周龄SPF鸡,随机分为对照组(Con)、攻毒组(Flu)、免疫后攻毒组(Vac+Flu)。以每只0.4 mL剂量免疫接种H9灭活疫苗,3周后以10~6 EID_(50)... [目的]本试验旨在探究H9N2亚型禽流感病毒攻击对H9灭活疫苗免疫SPF鸡呼吸系统的影响。[方法]选用36只3周龄SPF鸡,随机分为对照组(Con)、攻毒组(Flu)、免疫后攻毒组(Vac+Flu)。以每只0.4 mL剂量免疫接种H9灭活疫苗,3周后以10~6 EID_(50)的病毒量进行攻毒,采集拭子、血清、气管、肺组织等样品,通过血凝抑制(HI)试验、RT-PCR、荧光定量PCR(qPCR)等方法检测血清中HI抗体滴度、肺脏流感病毒M基因拷贝数以及免疫相关基因CD4、CD8、GATA3、T-bet、IL-4、IL-13、TNF-α、IFN-γ、Perforin、Granzyme、FasL、Fas等的表达量;并利用HE染色、免疫组织化学的方法观察气管、肺脏的病理变化及病毒特异性抗原NP蛋白的分布特征。[结果]HI试验结果显示,SPF鸡疫苗免疫后可产生较高的H9N2 AIV抗体效价。免疫保护试验和RT-PCR结果显示,SPF鸡疫苗免疫后攻毒仍能检测到机体排毒和流感病毒M基因在肺脏组织中的表达。HE染色和免疫组化结果显示,接种H9N2 AIV灭活疫苗后能够明显减轻SPF鸡气管和肺脏的病理损伤,降低气管、肺脏中的病毒载量。荧光定量PCR结果显示,接种H9N2 AIV灭活疫苗后能够提高SPF鸡肺脏中Th1、Th2细胞因子分泌水平,促进穿孔素/颗粒酶途径相关基因表达进而增强肺脏中细胞毒性反应。[结论]H9N2疫苗免疫鸡感染H9病毒后虽然仍存在排毒现象,但其抗病毒免疫系统活跃、其主要器官病毒载量降低,建议按照流感疫苗免疫程序进行免疫接种,提高对流感的防控水平。 展开更多
关键词 SPF鸡 h9N2亚型禽流感病毒 灭活疫苗 免疫相关基因
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Comprehensive understanding of the superior performance of Sm-modified Fe_(2)O_(3)catalysts with regard to NO conversion and H_(2)O/SO_(2)resistance in the NH_(3)-SCR reaction 被引量:7
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作者 Chuanzhi Sun Wei Chen +4 位作者 Xuanxuan Jia Annai Liu Fei Gao Shuai Feng Lin Dong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第3期417-430,共14页
Sm-doped Fe_(2)O_(3)catalysts,with a homogeneous distribution of Sm in Fe_(2)O_(3)nanoparticles,were synthesized using a citric acid-assisted sol-gel method.Kinetic studies show that the reaction rate for NO_(x)reduct... Sm-doped Fe_(2)O_(3)catalysts,with a homogeneous distribution of Sm in Fe_(2)O_(3)nanoparticles,were synthesized using a citric acid-assisted sol-gel method.Kinetic studies show that the reaction rate for NO_(x)reduction using the optimal catalyst(0.06 mol%doping of Sm in Fe_(2)O_(3))was nearly 11 times higher than that for pure Fe_(2)O_(3),when calculated based on specific surface area.Furthermore,the Fe_(0.94)Sm_(0.06)O_(x)catalyst maintains>83%NO_(x)conversion for 168 h at a high space velocity in the presence of SO_(2)and H_(2)O at 250℃.A substantial amount of surface-adsorbed oxygen was generated on the surface of Fe_(0.94)Sm_(0.06)O_(x),which promoted NO oxidation and the subsequent fast reaction between NO_(x)and NH_(3).The adsorption and activation of NH_(3)was also enhanced by Sm doping.In addition,Sm doping facilitated the decomposition of NH_(4)HSO_(4)on the surface of Fe_(0.94)Sm_(0.06)O_(x),resulting in its high activity and stability in the presence of SO_(2)+H_(2)O. 展开更多
关键词 Nh_(3)-SCR NO_(x)conversion Sm-doped Fe_(2)O_(3) SO_(2)and h_(2)O tolerance 168 h test
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Photocatalytic performance of TiO_2 catalysts modified by H_3PW_(12)O_(40), ZrO_2 and CeO_2 被引量:2
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作者 CAI Tiejun LIAO Yuchao +3 位作者 PENG Zhenshan LONG Yunfei WEI Zongyuan DENG Qian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第7期997-1004,共8页
The binary composite photo-catalysts CeO2/ZiO2, ZrO2/ZiO2 and the ternary composite photo-catalysts H3PW12040-CeO2/TiO2, H3PW12O40-ZrO2/TiO2 were prepared by sol-gel method. The catalysts were characterized by thermog... The binary composite photo-catalysts CeO2/ZiO2, ZrO2/ZiO2 and the ternary composite photo-catalysts H3PW12040-CeO2/TiO2, H3PW12O40-ZrO2/TiO2 were prepared by sol-gel method. The catalysts were characterized by thermogravimetric-differential thermal analysis (TG-DTA), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The photocatalytic elimination of methanol was used as model reaction to evaluate the photocatalytic activity of the composite catalysts under ultraviolet light irradiation. The effects of doped content, activation temperature, time, initial concentration of methanol and gas flow rate on the catalytic activity were investigated. The results showed that after doping a certain amount of CeO2 and ZrO2, crystallization process of TiO2 was restrained, particles of catalysts are smaller and more uniform. Doping ZrO2 not only significantly improved the catalytic activity, but also increased thermal stability. Doping H3PW12O40 alSO enhanced the catalytic activity. The catalytic activities of binary and ternary composite photocatalysts were significantly higher than un-doped TiO2. The dynamics law of photocatalytic reaction over the binary CeO2/TiO2 and ZrO2/TiO2 catalysts has been studied. The activation energy 15.627 and 15.631 kJ/mol and pre-exponential factors 0.5176 and 0.9899 s^-1 over each corresponding catalyst were obtained. This reaction accords to the first order dynamics law. 展开更多
关键词 TIO2 h3PW12O40 ZRO2 CEO2 photocatalytic elimination of methanol
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W2H2结合改良PBL教学法在《推拿治疗学》教学中的价值
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作者 公维志 李同军 +2 位作者 王永亮 戴缙 史文强 《继续医学教育》 2024年第7期34-37,共4页
目的分析在《推拿治疗学》课程教学中选择W2H2思维教学模式结合改良以问题为基础的教学法(problembased learning,PBL)的具体应用价值。方法选取2022年12月至2023年10月黑龙江中医药大学2020级针灸推拿学专业本科学生227名作为研究对象... 目的分析在《推拿治疗学》课程教学中选择W2H2思维教学模式结合改良以问题为基础的教学法(problembased learning,PBL)的具体应用价值。方法选取2022年12月至2023年10月黑龙江中医药大学2020级针灸推拿学专业本科学生227名作为研究对象,其中一班116名学生接受常规教学(对照组),二班111名学生接受W2H2思维教学模式结合改良PBL教学法(观察组),对比2组考核成绩优良率、学习能力、评教情况、教学能力。结果观察组考核成绩优良率(94.59%)高于对照组(82.76%),差异有统计学意义(P<0.05);观察组学习能力高于对照组,差异有统计学意义(P<0.001);观察组评教情况高于对照组,差异有统计学意义(P<0.001);观察组教学能力评分高于对照组,差异有统计学意义(P<0.001)。结论在《推拿治疗学》课程教学中选择W2H2思维教学模式结合改良PBL教学法能够提升学生学习能力及考核成绩,改善学生评教情况,教学应用效果良好。 展开更多
关键词 W2h2思维教学模式 改良PBL教学法 推拿治疗学 学习能力 教学能力 评教情况
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