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51.
Xie Shangfen Shen Hui 《保鲜与加工》1991,(4):93-96
The electrochromism of polyaniline films, which is prepared by electropolymer-ization from aniline in acidic aqueous solution onto platinum,is investigated in 330-700nm through in-situ ellipsometric technique. The results indicate that the ellipsometric peak of the reduced state(-0. 2V) of the film appears at 390-400nm and the oxidized state(0. 55V) at 500-530nm. The elec-trochromic reaction from the reduced "yellow" state to the oxidized "green" state is suggested via intermediate state whose ellipsometric peak appears at 466-470nm. 相似文献
52.
With the strengthening of constitutional protection that legal private property is not to be encroached upon and the land usufructs paid regime are further clear, the regime of urban housing dismantling and moving is facing a vigorous test. This paper analyzes three problems: the justice of the withdrawal of land use right, the legality of the alteration of the land use right and the rationality of the compensation of the land use right during the urban housing dismantling and moving. Finally, this paper tries to find some effective measures to solve the chain problems. 相似文献
53.
简介了全分布式控制网络构成的水电厂微机监测系统的结构、功能和故障诊断系统。它不仅能实时监测机组运行参数,且可对事故做出快速反应,大大提高了水电厂安全运行水平。由于网络采用总线拓扑结构和真正的全分布方式,因而在老电厂的技术改造中,不仅运行可靠、抗干扰能力强,且布置安装简便,投资省。 相似文献
54.
基于框架理论的变电站操作票自动生成系统 总被引:3,自引:0,他引:3
介绍了一种基于框架理论的变电站操作票自动生成系统。该系统用框架知识表示法来描述电力系统的设备参数,建构了一个直观的、层次分明的数据结构。通过融合框架理论于面向对象的语言VC 中,开发出了一个集通用、实用、智能于一体的操作票专家系统。 相似文献
55.
Fusheng Ma Shaozhong Kang Fusheng Li Jianhua Zhang Taisheng Du Xiaotao Hu Mixia Wang 《Agricultural Water Management》2007,90(3):190-196
The effects of water deficit in different fruit growth stages on the variation of stem sap flux of 6-year old greenhouse-grown pear-jujube trees were investigated. Treatments included sufficient water supply during the whole fruit-growing period (T1), mild water deficit during the flowering–fruit setting stage (T2), moderate water deficit during the fruit rapid growth stage (T3) and severe water deficit during the fruit maturing stage (T4). Results showed that significant compensation effect on stem sap flux after re-watering was observed in T2, but not in T3 and T4 stages. At the end of rapid growth stage, the diurnal variation of stomatal conductance generally had a similar trend as that of stem sap flux, but with a distinct midday depression from 12:00 to 14:00 p.m. In addition, a linear relationship between the relative available soil water content (RAWC) and the ratio of daily stem sap flux to that of sufficient water treatment was observed (R2 = 0.4489). 相似文献
56.
浅谈入世对我国节水灌溉设备发展的影响与应对措施 总被引:2,自引:0,他引:2
入世对我国节水灌溉设备的发展而言是风险与利益并存,挑战与机遇同在。本文分析了目前我国节水灌溉设备的现状,闸述了加入WTO对我国节水灌溉设备发展的影响,并提出应对措施。 相似文献
57.
依据1992年和1993年4-5月收集的标本,分析保安湖乌鳢渔获体系结构和生长特征。年龄由Ⅰ-Ⅶ龄构成,Ⅰ-Ⅺ龄分别占渔获总尾数的12.37%,24.74%、41.24%和17.53%。Ⅴ-Ⅶ龄极少公占4.12%。优势体长为31-42cm;优势体重为350-950g。体长与体重关系为W=0.007991L^3.1602。VonBertalanffty生长方程为Lt=77.3(1-e^-0.1988 相似文献
58.
Butyrolactone I (BTL-I) is a butanolide isolated from the deep-sea-derived fungus, Aspergillus sp. It provides a potential new target for the prevention and treatment of food allergies. This study aimed to investigate the metabolic and pharmacokinetic profile of BTL-I in rats. The metabolic profiles were obtained by UHPLC–Q-TOF-MS. As a result, eleven metabolites were structurally identified, and the proposed metabolic pathways of BTL-I were characterized. The main metabolites were the oxidative and glucuronidative metabolites. In addition, a sensitive UHPLC–MS/MS method was established for the quantitation of BTL-I in rat plasma (LOQ = 2 ng/mL). The method was fully validated and successfully applied to the pharmacokinetic study of BTL-I in rats after oral administration or intravenous administration. The oral bioavailability was calculated as 6.29%, and the maximum plasma concentrations were 9.85 ± 1.54 ng/mL and 17.97 ± 1.36 ng/mL for intravenous and intragastric dosing groups, respectively. 相似文献
59.
采用盆栽试验,在香蕉假植大苗培育过程中分别喷施浓度均为20 mg/L的赤霉素、复硝酚钠、胺鲜酯、α-萘乙酸钠等植物生长促进剂,以喷施清水为对照,通过不同处理假植大苗生长、物质累积及生理指标的分析,明确不同植物生长促进剂在香蕉假植大苗调控的作用。结果表明,本试验采用的4种植物生长促进剂对香蕉假植大苗培育的调控作用不同。与对照相比,叶面分别喷施20mg/L赤霉素、复硝酚钠均能有利于香蕉假植大苗假茎高及叶面积增加,提高叶绿素含量及叶绿素a、b含量,且以上两种植物生长促进剂平均提高叶绿素含量26.46%;喷施20mg/Lα-萘乙酸钠能提高假植苗假茎粗,提高干物质累积量16.11%积及吸氮量9.95%,促进氮磷钾养分吸收。叶面喷施赤霉素、复硝酚钠、α-萘乙酸钠和胺鲜酯均能显著提高香蕉假植大苗抗性,平均降低丙二醛含量14.64%、提高脯氨酸含量64.36%和SOD含量16.74%,且赤霉素还能显著提高POD含量82.13%。 相似文献
60.
高校国有资产保值增值存在的问题及对策 总被引:3,自引:0,他引:3
概述高校国有资产的表现形式,分析高校国有资产管理的现状及存在问题,提出高校国有资产保值增值的对策。 相似文献