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加州鲈肠道芽孢杆菌的筛选及其功能研究

华中农业大学学报 2024年第5期43卷 213-223页

作者：朱静静张永安涂加钢华中农业大学水产学院/农业微生物资源发掘与利用全国重点实验室武汉430070

为筛选对加州鲈(Micropterus salmoides)有益生效果的芽孢杆菌,从加州鲈肠道分离芽孢杆菌,检测其溶血性、产酶能力、生物被膜形成能力、对多种常见抗生素的敏感性、耐受人工胃肠液及体外拮抗诺卡氏菌的能力等,并将菌株拌料饲喂加州鲈后... 详细信息

为筛选对加州鲈(Micropterus salmoides)有益生效果的芽孢杆菌,从加州鲈肠道分离芽孢杆菌,检测其溶血性、产酶能力、生物被膜形成能力、对多种常见抗生素的敏感性、耐受人工胃肠液及体外拮抗诺卡氏菌的能力等,并将菌株拌料饲喂加州鲈后测定加州鲈体质量增长和炎症因子的表达。结果显示,从鉴定到的94株芽孢杆菌中筛选出无溶血性且产酶能力广的4株枯草芽孢杆菌K-3、K-12、K-13、K-22,4株菌均是强生物被膜形成株,对多种常见抗生素敏感,其中K-3、K-13菌株能在体外拮抗诺卡氏菌。4株菌在人工胃液(pH 4)和人工肠液中2 h的存活率达到80%以上。K-13试验组的体质量增长率显著高于对照组,K-12、K-13试验组肠道蛋白酶、脂肪酶活性显著高于对照组。此外,与对照组相比,K-13试验组头肾、脾、后肠中的促炎因子表达水平下调,抑炎因子表达水平上调,表明K-13菌株具有减轻加州鲈肠道炎症发生的潜力。综合分析,本研究分离筛选的枯草芽孢杆菌K-13株具有安全性高、产酶能力强、拮抗诺卡氏菌、促进加州鲈生长的特性,可作为加州鲈饲料添加的益生菌制剂。

关键词：加州鲈芽孢杆菌溶血特性产酶性能诺卡氏菌

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Reduced-order Kalman filtering for state constrained linear systems

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Journal of Systems Engineering and Electronics 2013年第4期24卷 674-682页

作者： Chaoyang Jiang yongan zhang Center for Control Theory and Guidance Technology Harbin Institute of Technology

This paper aims at solving the state filtering problem for linear systems with state constraints. Three classes of typical state constraints, i.e., linear equality, quadratic equality and inequality, are discussed. By using the linear relationships among different state variables, a reduced-order Kalman filter is derived for the system with linear equality constraints. Afterwards, such a solution is applied to the cases of the quadratic equality constraint and inequality constraints and the two constrained state filtering problems are transformed into two relative constrained optimization problems. Then they are solved by the Lagrangian multiplier and linear matrix inequality techniques, respectively. Finally, two simple tracking examples are provided to illustrate the effectiveness of the reduced-order filters.

关键词： state constraint state filtering reduced-order Kalman filter linear matrix inequality (LMI).

Robust Near-Hovering Flight Controller for Model-Scale Helicopters Via Parametric Approach

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Journal of Harbin Institute of Technology(New Series) 2015年第5期22卷 69-77页

作者： Zhigang Zhou yongan zhang Center for Control Theory and Guidance Technology Harbin Institute of Technology

This paper aims to provide a parametric design for robust flight controller of the model-scale helicopter. The main contributions lie in two aspects. Firstly,under near-hovering condition,a procedure is presented for simplification of the highly nonlinear and under-actuated model of the model-scale helicopter. This nonlinear system is linearized around the trim values of the chosen flight mode,followed by decomposing this high-order linear model into three lower-order subsystems according to the coupling properties among *** decomposition,the three subsystems are obtained which include the coupling subsystem between the roll( pitch) motion and the lateral( longitudinal) motion,the subsystem of the yaw motion and the subsystem of the vertical motion. Secondly,by using eigenstructure assignment,the problem of flight controller design can be converted into solving two optimization problems and the linear robust controllers of these subsystems are designed through solving these optimization problems. Besides, this paper contrasts and analyzed the performances of the LQR controller and the parametric controller. The results demonstrate the effectiveness and the robustness against the parametric perturbations of the parametric controller.

关键词： model-scale helicopter near-hovering robust flight controller robust eigenstructure assignment

Structural evolution of spray-formed Al-70wt.%Si alloys during iso-thermal holding in the semi-solid state

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Rare Metals 2005年第4期24卷 317-324页

作者： zhang Di CUI Hua WEI Yanguang zhang Jishan zhang yongan XIONG Baiqing The State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China General Research Institute for Nonferrous Metals Beijing 100088 China

The grain growth behavior of spray-formed Al-70wt.%Si alloys was studied in the semi-solid state. The specimens were isothermally heat-treated at various temperatures between the solidus and liquidus of Al-Si alloys and then quenched in water. The microstructure of reheated specimens was characterized using optical and scanning electron microscopies. The isothermal holding experiment was carried out to investigate grain growth behavior as a function of holding time and temperature in the semi-solid state. The coarsening mechanism and the effect of porosity on microstructure were also studied.

关键词： materials science grain growth behavior spray forming Al-70wt.%Si alloys semi-solid processing

小保当二号煤矿超长综采工作面初次来压规律分析

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陕西煤炭 2024年第3期43卷 41-47页

作者：张罗迅王鹏飞张永安陕西小保当矿业有限公司陕西榆林719000

为探究小保当二号煤矿132202智能超长综采工作面初采阶段的压力显现规律,采用在线应力监测设备实时监测综采工作面各液压支架的应力数据。结果显示,在超长工作面来压前工作面局部发生一次小规模压力显现;超长工作面开始初次来压具有分... 详细信息

为探究小保当二号煤矿132202智能超长综采工作面初采阶段的压力显现规律,采用在线应力监测设备实时监测综采工作面各液压支架的应力数据。结果显示,在超长工作面来压前工作面局部发生一次小规模压力显现;超长工作面开始初次来压具有分区来压的特点,机尾侧率先来压,之后工作面机头侧和中部陆续来压,且工作面机尾侧来压强度整体高于机头侧。超长工作面初次来压总持续时间约29 h,其中整个工作面强烈来压持续时间约7.0 h;工作面机头侧初次来压步距约79.6 m,工作面中部初次来压步距75.6~82.6 m,平均78 m,机尾侧初次来压步距约74.7 m。

关键词：超长工作面初次来压在线应力监测分区来压

Residual stress with asymmetric spray quenching for thick aluminum alloy plates

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International Journal of Minerals,Metallurgy and Materials 2023年第11期30卷 2200-2211页

作者： Ning Fan Zhihui Li Yanan Li Xiwu Li yongan zhang Baiqing Xiong State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.Ltd.Beijing 100088China GRIMAT Engineering Institute Co. Ltd.Beijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China

Solution and quenching heat treatments are generally carried out in a roller hearth furnace for large-scale thick aluminum alloy ***,the asymmetric or uneven spray water flow rate is inevitable under industrial production conditions,which leads to an asymmetric residual stress *** spray quenching treatment was conducted on self-designed spray equipment,and the residual stress along the thickness direction was measured by a layer removal method based on *** the asymmetric spray quenching condition,the subsurface stress of the high-flow rate surface was lower than that of the low-flow rate surface,and the difference between the two subsurface stresses increased with the increase in the difference in water flow *** subsurface stress underneath the surface with a water flow rate of 0.60 m^(3)/h was 15.38 MPa less than that of 0.15 m^(3)/*** simulated residual stress by finite element(FE)method of the high heat transfer coefficient(HTC)surface was less than that of the low HTC surface,which is consistent with the experimental *** FE model can be used to analyze the strain and stress evolution and predict the quenched stress magnitude and distribution.

关键词： aluminum alloy spray quenching residual stress layer removal method finite element method

Age-hardening characteristic of an Al-Zn-Mg-Cu alloy produced by spray deposition

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Rare Metals 2007年第2期26卷 163-168页

作者： WANG Feng XIONG Baiqing zhang yongan ZHU Baohong LIU Hongwei zhang Zhihui WANG Zixing State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

Al-10.8Zn-2.8Mg-1.9Cu alloy was synthesized by spray atomization and deposition technique. GP zones and age-hardening process in the alloy were investigated using high-resolution electron microscopy （HREM）, selected area diffraction （SAD）, and differential scanning calorimetry （DSC） analysis. The results indicated that spray deposition process accelerated the aging kinetics of the alloy at an aging temperature of 120℃, thereby reducing the peak aging time to 16 h. GPⅠ and GPⅡ are the two types of zones that are major precipitates for the alloy under peak-aged condition. The precipitation sequence for the alloy is also discussed.

关键词： aluminium alloy precipitation GP zone spray deposition

Temperature-regulated typeⅡgrass carp reovirus establishes latent infection in Ctenopharyngodon idella brain

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Virologica Sinica 2023年第3期38卷 440-447页

作者： Rui Jiang Jie zhang Zhiwei Liao Wentao Zhu Hang Su yongan zhang Jianguo Su College of Fisheries Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan430070China Laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and TechnologyQingdao266237China

Grass carp reovirus(GCRV)causes extensive infection and death in grass carp and black carp fingerlings,with a highly seasonal *** studies suggested that GCRV can become latent after primary *** this study,we investigated type II GCRV(GCRV-II)latency in asymptomatic grass carp with GCRV infection or exposure *** found that during latent infection,GCRV-II was detectable only in the brain of grass carp,unlike the multi-tissue distribution observed in natural ***-II only caused damage to the brain during latent infection,while in natural infection,brain,heart,and eye tissues had relatively higher viral *** also discovered viral inclusion bodies in infected fish ***,GCRV-II distribution in grass carp was notably affected by ambient temperature,with the virus targeting the brain only during low temperatures and multi-tissue distribution during high *** study provides insights into the mechanisms of GCRV-II latent infection and reactivation and contributes to the prevention and control of GCRV pandemics.

关键词： Grass carp Grass carp reovirus(GCRV) Latent infection Brain

双喷嘴下铝合金喷淋淬火冷却行为与残余应力研究

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稀有金属 2024年第8期48卷 1073-1084页

作者：范宁熊柏青李志辉李亚楠李锡武张永安中国有研科技集团有限公司有色金属材料制备加工国家重点实验室有研工程技术研究院有限公司北京有色金属研究总院

结合大规格板材喷淋淬火实际工况，测定双喷嘴喷淋条件下试样不同位置的淬火冷却曲线，并采用X射线衍射法测试淬火后试样表面残余应力分布，分析喷嘴间距和喷淋流量比对试样淬火冷却行为和残余应力的影响。结果表明，在双喷嘴水流量相... 详细信息

结合大规格板材喷淋淬火实际工况，测定双喷嘴喷淋条件下试样不同位置的淬火冷却曲线，并采用X射线衍射法测试淬火后试样表面残余应力分布，分析喷嘴间距和喷淋流量比对试样淬火冷却行为和残余应力的影响。结果表明，在双喷嘴水流量相同情况下，当两个喷嘴的射流重叠较多时，重叠区的冷却能力强于其他射流区；当两个喷嘴间距为100～120 mm时，试样不同位置的冷却行为基本一致；当两股射流相离较远时，未喷淋区的冷却能力弱于射流区；喷嘴间距在80～140 mm范围内，试样表面残余应力水平和分布基本一致。当双喷嘴喷淋水流量不同时，试样在低喷淋流量侧的冷却能力较低，随着双喷嘴喷淋水流量差异增大，试样冷却行为不均匀性增大。当喷淋流量比等于或大于1∶0.50时，高喷淋流量侧的残余应力与单喷嘴喷淋下的基本一致，而低喷淋流量侧的应力水平在过渡区明显降低后达到均匀分布。

关键词：铝合金喷淋淬火换热能力热通量残余应力