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化学工程师 2024年第2期38卷 83-86,91页

作者：邱崇粤林世明江毅唐琳中海油能源发展股份有限公司工程技术湛江分公司广东湛江524057 中海油常州涂料化工研究院有限公司上海海铠防腐工程技术分公司广东深圳518052 中海油服油田化学事业部湛江作业公司广东湛江524057 中海油服钻井事业部湛江作业公司广东湛江524057

传统石棉型钻机刹车块在高温工作条件下易脱落,且产生有毒致癌分解物。本文以环保纤维型材料制备的盘式钻机刹车块作为实验,各项性能实验结果,表明纤维型钻机刹车块的密度、冲击强度、摩擦系数、磨损率性能与石棉型钻机刹车块基本相似,... 详细信息

传统石棉型钻机刹车块在高温工作条件下易脱落,且产生有毒致癌分解物。本文以环保纤维型材料制备的盘式钻机刹车块作为实验,各项性能实验结果,表明纤维型钻机刹车块的密度、冲击强度、摩擦系数、磨损率性能与石棉型钻机刹车块基本相似,符合行业标准要求,且制动导热温度比石棉型钻机刹车块低,因此,纤维型钻机刹车块性能稳定,使用寿命较长,利于作业人员健康及设备工作效率。

关键词：钻机刹车块冲击强度摩擦性能玻璃纤维石棉

Analysis and research on Maximum Power Point Tracking of Photovoltaic Array with Fuzzy Logic Control and Three-point Weight Comparison Method

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Science China(Technological Sciences) 2010年第8期53卷 2183-2189页

作者： lin Kuang-jang lin Chii-Ruey Department of Energy and Refrigerating Air-Conditioning Engineering NTUTTaipeiChina Department of Mechanical Engineering NTUTTaipeiChina

The Photovoltaic Array has a best optimal operating point where the array operating can obtain the maximum ***, the optimal operating point can be compromised by the strength of solar radiation,angle,and by the change of environment and *** to the constant changes in these conditions,it has become very difficult to locate the optimal operating point by following a mathematical ***,this study will focus mostly on the application of Fuzzy Logic Control theory and Three-point Weight Comparison Method in effort to locate the optimal operating point of solar panel and achieve maximum efficiency in power generation. The Three-point Weight Comparison Method is the comparison between the characteristic curves of the voltage of photovoltaic array and output power;it is a rather simple way to track the maximum *** Fuzzy Logic Control,on the other hand,can be used to solve problems that cannot be effectively dealt with by calculation rules,such as concepts,contemplation, deductive reasoning,and ***,this paper uses these two kinds of methods to make simulation successively. The simulation results show that,the Three-point Comparison Method is more effective under the environment with more frequent change of solar radiation;however,the Fuzzy Logic Control has better tacking efficiency under the environment with violent change of solar radiation.

关键词： Photovoltaic Array Maximum Power Point Tracking(MPPT) Fuzzy Logic Control Three-point Weight Comparison Method

Two-Dimensional Fin Efficiency of Plate Fin-Tube Heat Exchangers Under Partially and Fully Wet Conditions

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Journal of Thermal Science 2002年第3期11卷 249-254页

作者： Jiin-Yuh jang Chien-Nan lin Natl Cheng Kung Univ Dept Mech Engn Tainan 70101 Taiwan

This paper presents the two-dimensional analysis for the efficiency of continuous plate fin-tube heat exchangers in staggered and in-lined arrangements under the dry, partially wet, and fully wet conditions for different heat transfer coefficient (h = 20 W/m2K to h = 80 W/m2K) and air relative humidity over the full range from φ= 0 % to φ= 100%. It is shown that the fin efficiencies of the staggered arrangement are higher than those for the in-lined arrangement, and the fully wet fin efficiency is 10~20% lower than that for a dry fin. The conventional 1-D sector method underestimates the fin efficiency up to 4 % as compared to the 2-D analysis.

关键词： fin efficiency plate fin-tube partially and fully wet.

聚磷酸盐在灰漠土和砖红壤中吸附-解吸附特性研究

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中国土壤与肥料 2024年第7期 101-107页

作者：张静雯迟海龙吴胜彪马林江席亮危常州张新疆石河子大学农学院新疆石河子832003

通过研究不同聚合度聚磷酸盐在两种不同类型土壤中的磷吸附-解吸特性,为聚磷酸磷肥肥效差异的解析和农业磷肥的应用提供理论依据。以北方灰漠土和南方砖红壤为供试土壤,以常规水溶磷肥(DAP)为对照,探究不同聚合度聚磷酸盐(APP1、APP2、A... 详细信息

通过研究不同聚合度聚磷酸盐在两种不同类型土壤中的磷吸附-解吸特性,为聚磷酸磷肥肥效差异的解析和农业磷肥的应用提供理论依据。以北方灰漠土和南方砖红壤为供试土壤,以常规水溶磷肥(DAP)为对照,探究不同聚合度聚磷酸盐(APP1、APP2、APP3、KTPP)在两种土壤中磷的吸附和解吸附特性,并进一步探究不同类型土壤理化性质与土壤磷吸附-解吸附量之间的相互关系。结果表明:在酸性土壤中,各处理土壤磷吸附能力表现为APP2>APP3>KTPP>APP1>DAP,土壤中磷解吸附能力为APP1>KTPP>DAP>APP3>APP2;在灰漠土中,各处理土壤磷吸附能力表现为APP2>APP1>APP3>DAP>KTPP,土壤中磷解吸附能力为KTPP>APP1>DAP>APP3>APP2。土壤各理化性质参数中土壤黏粒、铁铝氧化物含量与土壤磷最大吸附量(Q_(m))呈正相关关系。土壤pH、有机质和碳酸钙含量与Q_(m)呈负相关关系。综上所述,较高聚合度的聚磷酸盐(KTPP)在灰漠土中磷吸附能力弱,土壤磷有效性高,而较低聚合度的聚磷酸盐(APP1)在酸性土壤中的磷吸附能力弱,能保持较好的土壤磷平衡和供磷能力。土壤pH、有机质和碳酸钙含量越高,土壤黏粒和铁铝氧化物含量越低,则土壤对磷的吸附能力越低,磷的解吸越高,土壤磷有效性越高。

关键词：聚磷酸铵吸附解吸附

维普期刊数据库博看期刊

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单边螺栓连接中心支撑钢框架抗震性能分析

河南理工大学学报（自然科学版） 2024年第2期43卷 166-176页

作者：蔺新艳杨新宇王新武孙海粟刘欢欢 jang Il Young 河南理工大学土木工程学院河南焦作454000 洛阳理工学院河南省新型土木工程结构国际联合实验室河南洛阳471023 武汉理工大学理学院湖北武汉430070 金乌国立工科大学土木工程学院韩国龟尾39177

目的为研究支撑-半刚接钢框架结构体系的抗震性能,方法设计了一榀由嵌套式单边螺栓与T型钢构成的半刚性梁柱节点的中心支撑钢框架,并进行了拟静力试验与有限元数值模拟,通过观测整个试验现象,分析了其滞回、承载力、刚度退化、耗能等抗... 详细信息

目的为研究支撑-半刚接钢框架结构体系的抗震性能,方法设计了一榀由嵌套式单边螺栓与T型钢构成的半刚性梁柱节点的中心支撑钢框架,并进行了拟静力试验与有限元数值模拟,通过观测整个试验现象,分析了其滞回、承载力、刚度退化、耗能等抗震指标。结果结果表明:试件破坏过程明显经历了弹性段、塑性段、破坏段三个阶段,试件破坏模式主要为支撑受压失稳破坏,塑性变形主要累积在支撑体系上,整体呈现延性破坏特征;支撑断裂后,梁柱及T型钢节点无明显塑性变形,钢框架仍具有较高的安全储备,符合“强节点、弱构件”设计原则,表明了结构具有两道抗震防线;结论支撑与半刚接钢框架协同工作使得试件具有较高的抗侧刚度抵抗水平变形,且承载力较高、滞回性能稳定、耗能能力优良;单边螺栓在试验过程中的受力性能较普通高强螺栓并无较大差别,未出现严重的预紧力松弛现象,并能高效的保持螺栓预紧力。通过有限元数值模拟分析可知,减小支撑长细比,虽能有效提高结构的抗震性能,但长细比较小会导致支撑刚度增大,加速其余构件的损坏。故应以考虑结构的延性为前提,降低支撑的长细比,才能有效提高结构的抗震性能。

关键词：中心支撑单边螺栓 T型钢半刚性连接抗震性能

Effect of temperature on the effective thermal conductivity of n-tetradecane-based nanofluids containing copper nanoparticles

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Particuology 2015年第5期13卷 95-99页

作者： Haifeng Jiang Qianghui Xu Chao Huang lin Shi Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Thermal Engineering Tsinghua University

Nanofluids were prepared by dispersing Cu nanoparticles （-20nm） in n-tetradecane by a two-step method. The effective thermal conductivity was measured for various nanoparticle volume fractions （0.0001-0.02） and temperatures （306.22-452.66 K）. The experimental data compares well with the jang and Choi model, The thermal conductivity enhancement was lower above 391.06 K than for that between 306,22 and 360,77 K, The interfacial thermal resistance increased with increasing temperature, The effective thermal conductivity enhancement was greater than that obtained with a more viscous fluid as the base media at 452,66 K because of nanoconvection induced by nanoparticle Brownian motion at high temoerature.

关键词： Nanofluid Thermal conductivity High temperature Brownian motion

沉默PrxⅡ基因促进巨噬细胞对肝癌细胞的杀伤作用

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黑龙江八一农垦大学学报 2024年第2期36卷 77-83页

作者：冯琳孙率洋姜鹏吕树旗韩英浩黑龙江八一农垦大学生命科学技术学院大庆163319

为探究PrxⅡ对RAW264.7(小鼠单核巨噬细胞系)细胞杀伤HepG2(人肝癌细胞系)细胞的影响,阐明PrxⅡ基因调控RAW264.7细胞分泌细胞因子杀伤HepG2细胞的作用,利用慢病毒干扰技术制备PrxⅡ基因沉默的RAW264.7细胞系、MTT assay测定HepG2细胞... 详细信息

为探究PrxⅡ对RAW264.7(小鼠单核巨噬细胞系)细胞杀伤HepG2(人肝癌细胞系)细胞的影响,阐明PrxⅡ基因调控RAW264.7细胞分泌细胞因子杀伤HepG2细胞的作用,利用慢病毒干扰技术制备PrxⅡ基因沉默的RAW264.7细胞系、MTT assay测定HepG2细胞存活情况、ELISA法测定RAW264.7细胞分泌炎性因子情况、蛋白质免疫印迹法检测NF-κB信号通路相关蛋白质表达水平。结果表明:已成功制备PrxⅡ基因沉默的RAW264.7细胞系;MTT检测发现RAW264.7细胞上清液处理HepG2细胞后,shPrxⅡ组HepG2细胞存活率明显低于mock组,且呈时间依赖性;ELISA结果表明shPrxⅡ组RAW264.7细胞分泌的TNF-α含量明显高于mock组,IL-6和IL-1β含量明显低于mock组;蛋白质免疫印迹结果与mock组相比,PrxⅡ基因沉默的RAW264.7细胞中NF-κB信号通路明显被激活。由此得出结论,PrxⅡ基因能调控RAW264.7细胞分泌细胞因子,杀伤HepG2细胞,导致HepG2细胞死亡水平上升,研究结果可为以巨噬细胞为靶点的免疫疗法提供理论基础,为肝癌患者的免疫治疗提供新思路。

关键词： RAW264.7细胞系 HepG2细胞系 PrxⅡ NF-κB 炎性因子

Pseudomonas simiae MHR6产胞外多糖条件优化及抗氧化活性

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草原与草坪 2024年第4期44卷 189-196页

作者：刘晓婷张琛韩江茹李晓林姚拓甘肃农业大学草业学院草业生态系统教育部重点实验室甘肃省草业工程实验室中‐美草地畜牧业可持续发展研究中心甘肃兰州730070 金昌市金川区农业技术推广服务中心甘肃金昌737100

【目的】研究培养条件对Pseudomonas simiae MHR6生长及胞外多糖(EPS)产量的影响,并探究其抗氧化活性,为新型农业生物制剂的开发利用提供可靠的理论依据。【方法】以EPS产量为指标,通过单因素试验对菌株MHR6产EPS条件进行优化,并对EPS... 详细信息

【目的】研究培养条件对Pseudomonas simiae MHR6生长及胞外多糖(EPS)产量的影响,并探究其抗氧化活性,为新型农业生物制剂的开发利用提供可靠的理论依据。【方法】以EPS产量为指标,通过单因素试验对菌株MHR6产EPS条件进行优化,并对EPS的羟基自由基(OH^(-))、超氧阴离子(O_(2)^(·-))和过氧化氢(H_(2)O_(2))的清除作用进行了研究。【结果】经优化后,MHR6产EPS的最佳培养条件是:培养时间5 d、温度28℃、初始pH值8、接种量3%。当EPS质量浓度为1.0 mg/mL时,其OH^(-)、O_(2)^(·-)和H_(2)O_(2)的清除率分别为56.94%、64.08%和31.69%。【结论】最佳培养条件下EPS产量达到最大值,为6.16 mg/mL,比优化前提高了24.9%。抗氧化实验结果表明MHR6所产的EPS具有良好的抗氧化活性。

关键词：胞外多糖培养条件优化自由基清除抗氧化活性

The Arabidopsis bZIP1 Transcription Factor Is Involved in Sugar Signaling, Protein Networking, and DNA Binding

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Molecular Plant 2010年第2期3卷 361-373页

作者： Shin Gene Kang John Price Pei-Chi lin Jong Chan Hong Jyan-Chyun jang Department of Horticulture and Crop Science The Ohio State University Columbus OH 43210 USA Plant Biotechnology Center The Ohio State University Columbus OH 43210 USA Department of Plant Cellular and Molecular Biology The Ohio State University Columbus OH 43210 USA Department of Biochemistry Gyeongsang National University Jinju Gyeongnam 660-701 Korea

Sugar signaling is a mechanism that plants use to integrate various internal and external cues to achieve nutrient homeostasis, mediate developmental programs, and articulate stress responses. Many bZlP transcription factors are known to be involved in nutrient and/or stress signaling. An Arabidopsis Sl-group bZlP gene, AtbZIP1, was identified as a sugar-sensitive gene in a previous gene expression profiling study （Plant Cell. 16, 2128-2150）. In this report, we show that the expression of AtbZIP1 is repressed by sugars in a fast, sensitive, and reversible way. The sugar repression of Atb- ZIP1 is affected by a conserved sugar signaling component, hexokinase. Besides being a sugar-regulated gene, AtbZIP1 can mediate sugar signaling and affect gene expression, plant growth, and development. When carbon nutrients are limited, gain or loss of function of AtbZlP1 causes changes in the rates of early seedling establishment. Results of phenotypic analyses indicate that AtbZlP1 acts as a negative regulator of early seedling growth. Using gain- and loss-of-function plants in a microarray analysis, two sets of putative AtbZIP1-regulated genes have been identified. Among them, sugar-responsive genes are highly over-represented, implicating a role of AtbZlP1 in sugar-mediated gene expression. Using yeast two-hybrid （Y-2-H） screens and bimolecular fluorescence complementation （BiFC） analyses, we are able to recapitulate extensive C/S1 AtbZlP protein interacting network in living cells. Finally, we show that AtbZIP1 can bind ACGT-based motifs in vitro and that the binding characteristics appear to be affected by the heterodimerization between AtbZlP1 and the C-group AtbZIPs, including AtbZlP10 and AtbZlP63.

关键词： bZIP transcription factors sugar response protein dimerization microarray analysis BiFC EMSA ACGT motif.