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1.
独立学院制药工程专业化工原理实验教学内容改革研究   总被引:1,自引:0,他引:1  
提出独立学院制药工程专业化工原理实验课程的教学目的和确定其内容的原则,并对化工原理实验的教学内容和建设创新型化工原理实验室进行了探讨。  相似文献   

2.
浅析高校化学实验室废弃物的综合处理   总被引:1,自引:0,他引:1  
化学实验室的环境污染问题不容忽视,必须防患于未然。实验过程中产生各种废气、废水和固体废物等污染物,对人体的危害极大。本文分析了目前我国高校化学实验室"三废"污染的现状,简单阐明了造成化学实验室环境污染的主要原因,同时提出了实验室污染的防治措施。  相似文献   

3.
关于化学实验室废液处理的探讨   总被引:20,自引:0,他引:20  
王家祺 《化学教育》1998,19(3):30-31
化学实验室所产生的废液其特点是:数量少、种类多、组成经常变化,排放这些废液,如不加处理将直接污染环境,危害人们的健康,其后果十分严重。  相似文献   

4.
化工实验室是帮助学生巩固理论知识,掌握化工实验操作技能,培养理论联系实际,综合分析问题和解决问题能力的重要基地。本文主要介绍化工原理实验室建设中的一些新举措。  相似文献   

5.
科技部不久前再次发布公告称,批准建设宁夏回族自治区人民政府省部共建煤炭高效利用与绿色化工国家重点实验室.宁夏回族自治区人民政府将每年为实验室提供不低于 1000 万元的实验室建设、日常运行、开放课题设立和人才引进培养专项经费.  相似文献   

6.
将基础实验室含铜废液的处理、回收及检测创新性地设计为大型综合性实验课题,增加了学生理论与实际相结合的能力,培养了学生的环保意识;同时进行教学反思,对如何减少实验室废液提出了可行性建议,以期加强高校化学实验室的废液污染控制;借此推动化学实验课程的教学改革,保护环境.  相似文献   

7.
前言     
正化工资源有效利用国家重点实验室前身为2000年8月成立的可控化学反应科学与技术教育部重点实验室.2006年6月27日,由中华人民共和国科学技术部批准筹建国家重点实验室,2009年1月正式通过验收.实验室首届学术委员会主任由中国科学院院士周其凤教授担任,首届实验室主任由中国科学院院士段雪教授担任.现任学术委员会主任周其凤教授,常务副主任段雪教授,实验室主任何静教授.  相似文献   

8.
正化工资源有效利用国家重点实验室(北京化工大学)前身为2000年8月成立的可控化学反应科学与技术教育部重点实验室,2006年6月27日由中华人民共和国科学技术部批准筹建国家重点实验室,2009年1月4日正式通过验收.实验室首届学术委员会主任由中国科学院院士周其凤教授担任,首届实验室主任由中国科学院院士段雪教授担任.现任学术委员会主任为周其凤教授,常务副主任为段雪教授,实验室主任为何静教授.  相似文献   

9.
实验室常见废弃物的处置   总被引:4,自引:0,他引:4  
实验室废弃物中许多是有毒有害物质,有些还是剧毒物质和强致癌物质如果不进行处理随意排放,将会污染空气和水源,造成环境污染,危害人体健康.目前我国仅有少数实验室有“三废”处理设施.随着人们环境意识的增强,实验室也必须加强对废弃物的处理.以下汇集一些实验室常见废弃物的处  相似文献   

10.
正密度或黏度较大的天然石油或常规石油中的重质组分在石油工业界通常被称为"重质油".重质油是未来世界石油能源的主要来源之一,也是非常重要的化工资源,高效利用重质油是国家石油资源发展战略的重要方向.重质油国家重点实验室是一个以重质油加工利用为主要研究内容的国家重点实验室.实验室建设在中  相似文献   

11.
12.
PHOTOLYSIS AND RADIOLYSIS OF NITROMETHANE AND NITROETHANE   总被引:1,自引:0,他引:1  
Abstract— Prolonged photolysis of nitromethane and nitroethane in liquid and vapour phases, with simultaneous photolysis of the nitrogen dioxide formed, was studied in the absence and presence of cupric oxide. A high-pressure quartz immersion lamp providing the full range of visible and u.v. spectrum, with a high output of radiation at 366 and 313 mμ, was employed as source of light. The products of photolysis were detected by microanalytical methods, infrared-absorption spectrum analysis and gas chromatography. Photolysis of liquid nitro-alkanes resulted in formation of many compounds; saturated hydrocarbons, and in the case of nitroethane, ethylene, were submitted to detailed examination. Photolysis in the vapour phase was carried out in a specially designed glass apparatus. The main products were nitrogen dioxide, aldehydes and polyaldehydes; hydrocarbons were not estimated.
Liquid nitromethane and nitroethane were also irradiated with γ-rays from a 60Co source. The radiolysis products were similiar to those obtained on photolysis. The mechanism of photolytic decomposition of nitroalkanes is proposed and discussed.  相似文献   

13.
Abstract

2-(Thiocyanatoacetyl)thiophene 2 and its selenium analog 3 couple with diazotized anilines and yield 3-aryl-2-imino-5-(2-thenoyl)-2,3-dihydro-1,3,4-thiadiazoles 6 and 3-aryl-2-imino-5-(2-thenoyl)-2,3-dihydro-1,3,4-selenadiazoles 7 respectively. The reactions of both 6 and 7 with nitrous acid, acetic anhydride and benzoyl chloride are described. Azo coupling of 2-amino-4-(2-thienyl)thiazole 17 and its selenazole analog 18 with diazotized anilines yielded the arylazo derivatives 19 and 20 respectively. Reaction of the hydrazidoyl bromide 16 with potassium thiocyanate, potassium selenocyanate, thiourea and selenourea yields 6, 7, 19, and 20 respectively.  相似文献   

14.
9-氨基壬酸系从癸二酸经单酯化、氨化和Hofmann重排制得。该单体以10克规模在玻璃管中和以4公斤量在15升聚合釜中,于260℃聚合成聚壬酰胺。聚合物在288℃纺丝,120℃牵伸,得到尼龙-9纤维。测定了聚合物和纤维的结构和多种性能。  相似文献   

15.
用顺丁烯二酸酐 (MAH)对具有分子包结能力的 β 环糊精 (β CD)进行化学改性 ,合成出了丁烯二酸单酯化 β CD单体 (MAH β CD) .通过氧化还原自由基引发MAH β CD与N 异丙基丙烯酰胺 (NIPA)聚合 ,合成出含 β CD结构单元的新型水凝胶 .用核磁共振、红外光谱及元素分析对MAH β CD单体及共聚物的结构和组成进行了表征 .溶胀研究结果表明 ,该水凝胶具有较好的pH、温度及离子强度敏感性 ;并且水凝胶在较高羧基(—COOH)含量和弱碱环境中 ,仍能表现出明显的温敏性  相似文献   

16.
生物质热解、加氢热解及其与煤共热解的热重研究   总被引:36,自引:3,他引:36  
在加压热天平上用非等温热重法进行生物质(锯末、稻壳)在N2气氛下的热解和加氢热解研究。考察了升温速率(5~25℃/min)和压力(0.1~7MPa)的影响,求取了热解动力学参数,并研究了生物质与煤在常压N2气下的共热解过程。研究结果表明:生物质在400℃左右即完成热解反应,总失重率大于70%(W%,daf.),热解时仅一个峰位于300℃左右;与煤热解行为相同,随升温速率及压力的升高,转化率下降,DTG峰移向高温,但由于热解反应在较低温度下进行,氧气的存在对生物质热解TG和DTG的影响远小于煤热解。证明生物质热解以其内部氢对自由基的饱和及分子重排反应为主。生物质热解可用一级反应动力学处理,主要热解阶段及表现活化能分别为:锯末,267~314℃,69.66kJ/mol;稻壳,283~310℃,53.45kJ/mol;生物质由于与煤的热分解温度相差很大,因而在其共热解过程中无协同作用。  相似文献   

17.
Abstract— The spectra of absorption, fluorescence and excitation of monolayers and thin films containing chlorophyll a together with a carotenoid (cis-β-carotene, trans-β-carotene, fucoxanthin, or zeaxanthin), were measured at — 196°C. The concentration ratios used, (Chl)/(Car), were 6:1, 4:1, 3:1, 2:1, 1:1 and 1:3, and the area densities, 3·70, 2·55, 1·76, 0·71, 0·37 and 0·17 nm2/pigment molecule. In dilute monolayers, (3·70 nm2/molecule), with a constant concentration ratio (Chl)/(Car) = 3:1, evidence of three β-carotene forms, with absorption bands at 460, 500 and 520 nm (C460, C500 and C520), and of a chlorophyll a form with an absorption band at 669–672 (Chl669–672) was found. On increasing the density to 0·2–0·3 nm2/molecule, a conversion of C460 and C520 into C500, was observed, and several more additional (probably more strongly aggregated) chlorophyll a forms appeared, with absorption bands at 672–733 nm. With excess carotene [(Chi)/(Car) = 1:3] the forms C460, C500, C520 and Chl669–672 were present even in the most dense films (0·2–0·3 nm2/molecule). The same was found with other carotenoids: if one of the pigments was in excess, aggregated forms of the other tended to disappear. In the transfer of energy from carotenoids to chlorophyll a, C500 was found to be the main donor. In layers with a concentration ratio (Chl)/(Car) = 3:1, the efficiency of transfer was less than 10 per cent at the lowest density used (3·70 nm2/molecule); it increased to 50 per cent, as the density was increased to 0·20 nm2/molecule. When the relative concentration of the carotenoid was increased to (Chl)/(Car) = 1:1, the efficiency of energy transfer dropped to 25 per cent even at 0·20 nm2/molecule. It seems that the efficiency of energy transfer between carotene molecules (prior to its transfer to chlorophyll a) is low, and effective transfer occurs only between β-carotene and immediately adjacent chlorophyll a molecules.  相似文献   

18.
The attractive Interactions between typically hydrophobic molecules such as hexane or CCl4, and the repulsive Interactions between extremely hydrophilic molecules such as poly(ethylene oxide) (PEO), when immersed in water, as well as the interactions between these molecules and water, have been examined from a surface thermodynamic viewpoint, taking the changes in surface free energy into account, as a function of temperature. It was found that attractive hydrophobic Interactions are not, as vas generally believed up to now, invariably entropic. Hydrophobic Interactions can be mainly enthalpic or mainly entropic, or more or less equal mixtures of both, depending on each individual case; however, all hydrophobic interactions are polar (in the sense of Lewis acid-base) in nature. Repulsive hydrophilic interactions are enthalpic, and also polar in nature. The interaction between hydrophobic solutes and water is mainly enthalpic, and is apolar in nature.  相似文献   

19.
Conchostracans, with a laterally compressed body enclosed between two symmetric valves, live swimming in fresh or brackish water. The carapace valve has a number of growth bands with various sculptures. The general trend of sculptural evolution is from smooth to punctate-minute polygon-medium reticulation-large reticulation, while these punctate, polygonal and various reticulate patterns may separately develop into various radial ridges. The development of sculpture can be well explained by mechanical principle. Functional morphology of carapace is discussed in the light of mechanics in this paper.  相似文献   

20.
Abstract— As models for novel fluorescent probes, we have synthesized three isomeric hydroxystilbazole systems (4′-hydroxy-substituted 2-, 3-, and 4-stiIbazoles), examined their photocyclization-oxi-dation to four hydroxyazaphenanthrene systems, and made a preliminary study of their absorption and fluorescence spectra. All three stilbazoles can be prepared easily by addition of the isomeric picoline anions to 4-methoxybenzaldehyde, followed by dehydration and deprotection. Photocyclization proceeds efficiently, furnishing a single product isomer from each of the 2- and 4-stilbazole systems, and two isomeric azaphenanthrenes from the 3-stilbazole. The stilbazoles all have intense UV absorbance bands whose maxima depend upon solvent and pH; all three isomers have relatively similar spectra under neutral conditions and all three show a large red shift in base; in acid, however, the 2-and 4-stilbazole isomers show a greater red shift than the 3-stilbazole. The fluorescence of the stilbazoles is also solvent dependent, shifting to the red in more polar medium; red shifts are also observed in acid and base, but in acid, the 3-stilbazole shows a larger shift. The azaphenanthrene photocyclization products show absorbance spectra typical for quinolines and isoquinolines; their absorptivities are less than the stilbazoles, but their fluorescence is more intense. In general, the benzoquinolines have longer wavelength but weaker fluorescence than the benzoisoquinolines. Also, those isomers in which the resonance effects of the hydroxy and nitrogen groups can reinforce one another show longer wavelength emissions of greater intensity. All seven systems show dual fluorescence in water under neutral conditions, suggesting the emission from both non-ionized and ionized species in the excited state. In one case, the benzoisoquinoline system derived from 4′-hydroxy-4-stilbazole, an emission at 640 nm, observed in water over a wide pH range, is ascribed to a zwitterionic phototautomer. These stilbazoles, benzoquinolines and benzoisoquinolines may prove to be useful spectroscopic probes.  相似文献   

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