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1.
王美文 《化学教育》2003,24(3):27-29
以2003年高考《考试说明》(理综 )在能力要求、考试范围、考试形式与试卷结构和题型示例中的变化为依据,参照2002年、2003年(春季)高考理科综合试卷评价,分析2003年夏季高考理科综合试卷的命题指导思想及试卷特点。对2003年(3+X)高考理科综合及化学单科的后期复习提出注重基础、加强学科内综合能力;突出能力,加强学科内、学科间知识透移能力;体现理论联系实际、渗透研究性学习意识的复习建议。  相似文献   

2.
高考命题如何对中学化学教学发挥正面导向作用,中学化学教育如何适应高考命题改革和实现素质教育目标。笔者认真总结了2008年理科综合能力测试全国卷Ⅰ化学部分的特点,并结合考生答题情况对高考化学复习作了深刻的反思,同时也对高考试题存在的问题提出了商榷。  相似文献   

3.
高考命题如何对中学化学教学发挥正面导向作用,中学化学教育如何适应高考命题改革和实现素质教育目标.笔者认真总结了2008年理科综合能力测试全国卷Ⅰ化学部分的特点,并结合考生答题情况对高考化学复习作了深刻的反思,同时也对高考试题存在的问题提出了商榷.  相似文献   

4.
期刊热点启示——源于《化学教育》期刊的高考题评析   总被引:1,自引:0,他引:1  
陈世华 《化学教育》2005,26(10):39-41
研究2005年高考化学试题,发现其命题特点之一是关注社会热点,注重化学社会价值的开发与利用.以2005年高考热点——苏丹红为例,浅谈高考试题对中学化学教育的启示.  相似文献   

5.
张世仑 《化学教育》1989,10(2):9-11,39
自1978年恢复全国统一高考11年来,全国高考化学命题经过四个阶段的发展、变迁,已基本实现了两个重大转变:即试题的内容从考查知识为主逐步过渡到以考查能力为主:题型从主观题型为主逐步过渡到以客观题型为主。整个命题的设计、题型选择、分数常模等逐步走向科学化、标准化的道路。本文根据历届高考化学试题的统计分析,对各阶段试题的特点和变迁做了分析和总结性阐述。  相似文献   

6.
王美文 《化学教育》1999,20(12):11-15
1999年高考化学试题的特点是:考查素质、联系实际、重视实验、体现创新。为适应2000年高考命题在内容与形式上的进一步改革,在总复习中必须以知识为依托,立足于能力,扩大视野深化知识,做到读书求甚解,做题善多思。  相似文献   

7.
从近年广东高考看2010年广东理科综合化学考纲   总被引:1,自引:0,他引:1  
夏时君 《化学教育》2010,31(4):43-45,66
2010年广东课改实验区高考模式由"3+1+X"变为"3+理科综合/文科综合",如何更好地适应新形势下高考备考要求?从近年广东高考的命题模式、考试模式、解释模式、试题特点等方面进行分析,对新考纲的外延及内涵进行研读。  相似文献   

8.
王军翔 《化学教育》2006,27(10):32-33,36
每年的高考命题备受广大教育工作者的关注,高考一结束,研究高考试题的文章就络绎不绝地见诸于各类报刊上。为了使广大教育工作者科学地研究高考命题,更好地理解高考命题的实质,把握高考命题的趋势,改进学科教学,积极推进课改,也为了使其更好地搞好高考复习工作,我认为研究高考命题应坚持以下正确的认知取向。  相似文献   

9.
金伯明 《化学教育》2005,26(12):23-25
按照新课程的评价理念,通过命题实例,以命题涉及的范围为视角,探索了初中化学“紧扣基础,灵活多变;重视过程,考查方法;渗透人文,强化教育;源于生活,注重联系;模仿探究,体验活动;开放创新,张扬个性;运用史料,验证假设;提供事实,分析综合”的8项命题策略。  相似文献   

10.
鲁芹  颜桂炀  郑柳萍 《化学教育》2019,40(17):38-43
基于“SEC”一致性分析模式,对福州、厦门、泉州的中考化学实验试题与《义务教育化学课程标准(2011年版)》中实验内容主题和认知水平要求进行一致性编码分析,总结实验题的命题特点,提出实验教学应有所侧重,命制实验题应紧扣课程标准要求。  相似文献   

11.
利用手持技术改进测定乙醇分子结构实验   总被引:1,自引:0,他引:1  
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。  相似文献   

12.
13.
由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。  相似文献   

14.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

15.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

16.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

17.
实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。  相似文献   

18.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.  相似文献   

19.
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.  相似文献   

20.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

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