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Search Results: 1 - 10 of 120719 matches for " 平新亮 "
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纳米管阵列表面流动沸腾传热特性的实验研究
,杨文刚,史晓,陶金,邢晓康
化工进展 , 2013,
Abstract: 利用阳极氧化法在钛换热管内表面制备出了一层管阵列结构纳米薄膜。以该纳米管阵列表面管为传热元件,蒸馏水为工质,采用管外电加热竖管强制循环工艺,在恒质量流速下考察了纳米管阵列表面管的流动沸腾传热性能。在实验的基础上,得出了纳米管阵列表面管流动沸腾传热系数关联式。实验结果表明,与光滑表面管相比,流动沸腾传热温差降低了30%~55%,在没有增加阻力的情况下,沸腾传热系数提高了1.5~2.2倍。
肌苷菌核酸代谢关键酶缺失和形成选育腺苷菌的研究*
柏建,朱晓宏,张一,王红连,邓崇
微生物学通报 , 2003,
Abstract: 以肌苷产生菌BacillusSubtilis JSIM 1 0 1 9为出发菌株 ,根据B. subtilis核酸代谢理论设计不同筛选模型 ,用物理、化学诱变剂对亲株进行诱变处理 ,先后有序地获得不同关键酶的缺失或回复即特殊的营养缺陷型以及抗某些代谢类似物的突变株 ,解除终产物对代谢物的抑制和阻遏 ,获得了几株黄嘌呤营养缺陷型并对 8氮鸟嘌呤具有抗性的突变株X 1 3等 ,获得的突变株经单菌分离后得到X 1 3 4 ,36℃培养 72h在培养基中最高积累 1 2 4 3g/L腺
Henosepilachna vigintioctopunctata susceptibility to Ttripterygium wilfordii and Datura stramonium extracts
茄二十八星瓢虫对雷公藤和曼陀罗提取物的敏感性

李保同,闫 超,,汤丽梅
中国生态农业学报 , 2012,
Abstract: The influence of host plants on the larvae were investigated using the dipping and biochemical methods to determine the susceptibility of Henosepilachna vigintioctopunctata larvae that feed on eggplants, potatoes, tomatoes and nightshades to Ttripterygium wilfordii and Datura stramonium extracts and the activities of the corresponding acetylcholinesterase (AChE) and detoxification enzymes. The results indicated that LC50 values of T. wilfordii extract for larvae fed on eggplants, potatoes, tomatoes and nightshades were 1.407 9 mg·L-1, 1.595 8 mg·L-1, 1.464 7 mg·L-1 and 1.109 7 mg·L-1 and the relative toxicities were 78.82, 69.54, 75.76 and 100, respectively. LC50 values of D. stramonium extract for larvae fed on eggplants, potatoes, tomatoes and nightshades were 0.641 7 mg·L-1, 0.610 3 mg·L-1, 0.758 0 mg·L-1 and 0.488 3 mg·L-1 and the relative toxicities were 76.09, 80.01, 64.42 and 100, respectively. Compared with the susceptibility of larvae fed on eggplants, potatoes and tomatoes, the susceptibility of larvae fed on nightshades to T. wilfordii and D. stramonium extracts were significantly enhanced. The activities of AChE, glutathion-S-transferase (GST), carboxyl esterase (CarE) and mixed function oxidase (MFO) were highest for larvae fed on eggplants, followed by those fed on potatoes, tomatoes and then nightshades. Compared with AChE and GST activities of larvae fed on eggplants and potatoes, AChE and GST activities of larvae fed on tomatoes and nightshades were significantly suppressed. Also compared with CarE activity of larvae fed on eggplants, CarE activities of larvae fed on potatoes, tomatoes and nightshades were significantly suppressed. There were significant differences in MFO activity of larvae fed on the four host plants. T. wilfordii and D. stramonium extracts restrained AChE and GST, CarE and MFO activities of larvae fed on eggplants, potatoes, tomatoes and nightshades. AChE activity of larvae fed on potatoes was most significantly suppressed by T. wilfordii and D. stramonium extracts, that of AChE of larvae fed on eggplants and tomatoes was obviously suppressed and yet that of AChE activity of larvae fed on nightshades was relatively suppressed. CarE activity of larvae fed on nightshades, that of MFO of larvae fed on potatoes were significantly restrained by T. wilfordii and D. stramonium extracts. The induction or restraint of detoxification enzymes by allelochemicals in host plants were the main possible reasons for the differences in pesticide susceptibilities of H. vigintioctopunctata larvae.
神农架巴山冷杉天然林凋落量及养分特征
春敏莉, 谢宗强, 赵常明, 樊大勇,,
植物生态学报 植物生态学报 , 2009, DOI: 10.3773/j.issn.1005-264x.2009.03.008
Abstract: ?研究了湖北神农架巴山冷杉(Abiesfargesii)天然林凋落物量、凋落物N、P、K、Ca、Mg的含量及其归还量。结果表明:巴山冷杉天然林的年凋落量为5702.99kg·hm–2;巴山冷杉林的凋落物组成比较丰富,主要有落叶、落枝、球花、球果和其他5部分,其中以落叶为多,占总凋落量的46.00%;凋落量的月变化模式呈双峰型,分别在2006年10~11月和2007年4~5月达到峰值;凋落物养分含量的大小顺序为:N>K>Ca>P>Mg;N、P、K、Ca、Mg的年归还量分别为:39.1063、4.5346、13.4367、5.4965和0.0911kg·hm–2;就凋落物各组分的养分年归还量而言,落叶的养分归还量远远大于其余组分的养分归还量,占总归还量的52.65%。因此,不论凋落量还是养分归还量,巴山冷杉林凋落物中的落叶都占绝对优势。
辐照对落叶松八齿小蠹发育和繁殖的影响
詹国,周景清,,王跃进,,李柏树
核农学报 , 2011,
Abstract: 在室内采用华北落叶松新鲜木段饲养落叶松八齿小蠹(IpssubelongatusMots.),木段中的幼虫、蛹采用60Coγ射线,成虫采用9MeVX射线进行辐照处理。辐照后在华北落叶松木段上发育和繁殖的结果表明,幼虫经20~60Gyγ射线辐照后,能发育为成虫并繁殖F1代幼虫,80~120Gy处理后能发育为成虫,但成虫无侵染力和繁殖力;蛹经20~100Gy辐照后,能发育为成虫并繁殖F1代幼虫,120~140Gy处理后可发育为成虫,但无F1代幼虫出现。成虫经过4次X射线辐照试验的结果表明,40~120Gy处理后能繁殖F1代幼虫或成虫,140Gy以上剂量处理后无F1代幼虫出现。因此,以辐照导致小蠹不能繁殖子代幼虫作为检疫处理的标准,则落叶松八齿小蠹的幼虫、蛹、成虫的检疫处理剂量分别为80、120和140Gy。
基于地质雷达的隧道综合超前预报技术
,刘永权,*,*杨忠,涂义
岩石工程学报 , 2015,
Abstract: 以地质雷达为超前预报的主要手段,结合tgp206地震反射波法和工程地质调查法,针对某特长隧道开展综合超前地质预报。通过时域有限差分(fdtd)法,得到了掌子面前方典型不良地质体正演模拟合成图,以此作为地质雷达实际探测图像解译的基础;采用tgp206超前地质预报系统对掌子面前方100m范围内进行长距离预报,在接近不良地质体时,用地质雷达对掌子面前方20~30m范围进行更精确的短距离预报;将该法应用于实际工程断层破碎带和富水带的预报中,预报结果较为准确,有效指导了隧道的安全施工,该综合超前地质预报方法可为同类工程提供借鉴。
茄二十八星瓢虫对雷公藤和曼陀罗提取物的敏感性
李保同,闫 超,,汤丽梅
中国生态农业学报 , 2012,
Abstract: 为研究寄主植物对茄二十八星瓢虫药剂敏感性及体内酶活力的影响,采用浸渍法分别测定了取食茄子、马铃薯、番茄和龙葵的茄二十八星瓢虫幼虫(以下简称幼虫)对雷公藤和曼陀罗提取物的敏感性,用生化方法测定了雷公藤和曼陀罗提取物对幼虫体内乙酰胆碱酯酶(AChE)和主要解毒酶活性的影响。结果表明,雷公藤提取物对取食茄子、马铃薯、番茄和龙葵的幼虫LC50值分别为1.4079mg·L-1、1.5958mg·L-1、1.4647mg·L-1和1.1097mg·L-1,相对毒力指数为78.82、69.54、75.76和100;曼陀罗提取物对取食茄子、马铃薯、番茄和龙葵的幼虫LC50值分别为0.6417mg·L-1、0.6103mg·L-1、0.7580mg·L-1和0.4883mg·L-1,相对毒力指数为76.09、80.01、64.42和100;取食龙葵的幼虫对2种植物提取物的敏感性显著高于取食茄子、马铃薯和番茄的幼虫。取食4种寄主植物的幼虫体内靶标酶AChE和主要解毒酶谷胱甘肽-S-转移酶(GST)、羧酸酯酶(CarE)、多功能氧化酶(MFO)活力顺序均为茄子>马铃薯>番茄>龙葵。其中,取食番茄和龙葵的幼虫体内AChE和GST活力显著低于取食茄子和马铃薯的幼虫,取食马铃薯、番茄和龙葵的幼虫CarE活力显著低于取食茄子的幼虫,取食4种寄主植物的幼虫MFO活力差异达极显著水平。雷公藤和曼陀罗提取物对幼虫体内AChE和GST、CarE和MFO活性均有抑制作用。其中,对取食马铃薯幼虫的AChE活力抑制作用最强,其次为取食茄子和番茄的幼虫,对取食龙葵的幼虫抑制作用最低。雷公藤和曼陀罗提取物对取食龙葵幼虫CarE活力的抑制作用最强,而对取食马铃薯的幼虫MFO活力的抑制作用最强。寄主植物中的次生物质对解毒酶的诱导或抑制可能是引起药剂敏感性差异的主要原因。
南阳HNR热电厂工程单节和两节DX挤扩灌注桩的试验研究
沈保汉,王衍,刘振,贺德,耿瑜
工业建筑 , 2009, DOI: 10.13204/j.gyjz200902004
Abstract: 通过现场静荷载试验,在膨胀土地基中对桩身穿越大气影响深度并以硬塑黏土为承力盘和桩端持力层的单节DX挤扩灌注桩及以硬塑黏土为上承力盘持力层和以硬塑—坚硬黏土为下承力盘和桩端持力层的两节DX挤扩灌注桩的极限承载力进行判定,分析其荷载传递机理,并对两类桩的侧阻力、盘端阻力和桩端阻力的分配及其发展规律进行研究。
影响DX挤扩灌注桩竖向抗压承载力的因素
沈保汉,贺德,孙君,刘振,田忠生
工业建筑 , 2008, DOI: 10.13204/j.gyjz200805007
Abstract: 对影响DX挤扩灌注桩竖向抗压承载力的诸多因素桩身、承力盘(岔)的直径大小,承力盘(岔)的数量、间距和位置,承力盘(岔)端部土层的特性,盘腔的首次挤扩压力值及成孔成桩的施工工艺和施工质量等予以介绍。
DX多节挤扩桩的产生及特点
沈保汉,贺德,刘振,郭桂霞,孙君
工业建筑 , 2004, DOI: 10.13204/j.gyjz200403001
Abstract: 介绍了一种挤孔式变截面桩———DX多节挤扩桩及DX挤扩装置,详细地比较了DX挤扩装置与YZJ型支盘挤扩机的技术性能,此外还介绍了DX桩的特点。
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