我国中学化学课程中情感态度与价值观目标内涵的历史演变

情感态度与价值观目标在本次新课程改革中得到前所未有的重视。通过对我国历次化学课程标准或教学大纲中情感态度与价值观目标的历史梳理,分析出其变化的特征,以便帮助教师正确认识情感态度与价值观目标的内涵。     

化学教学设计中三维目标设计与叙写的问题与对策

针对化学教学设计中三维教学目标的设计与叙写的突出问题,从理论与实践层面进行了分析,并提出了解决问题的对策：（1）过程与方法是学生学习的过程和方法,不能设计成教师教学的过程与方法;过程与方法既是实现教学目标的手段,又是学生学习的目标,是相互关联的,不能割裂,陈述时要选择适宜的动词和恰当的行为结果。（2）情感态度是心理倾向,价值观是情感发展的结果,情感态度与价值观是生命发展的心理需求。在教学设计中教师要注重发掘教学内容中情感态度价值观素材,并明确目标达成方式。（3）三维目标是一个整体,不能割裂;整合目标,才能从整体上把握三维目标;自觉践行,才能逐步提高设计能力。     

"情感态度与价值观"目标在中学化学教学中落实的建议

"情感态度与价值观"教学目标是新课程提出的三维教学目标之一.分析了目前中学化学教学中对"情感态度与价值观"目标实施所存在的一些问题,提出了"情感态度与价值观"目标落实策略的建议.     

重视主体体验落实情感态度与价值观目标——以“富集在海水中的元素——氯”的导课为例

从三维目标中情感态度与价值观目标的落实问题出发,以2个具有代表性的导课案例,从学生“主体体验”的角度探讨了如何在化学课堂中有效地实现情感态度与价值观目标:从理念上重视,在教学设计中体现,在教学过程中落实.     

中学化学情感态度价值观教学目标实施的影响因素分析

情感态度价值观教学目标是新课程提出的三维教学目标之一。本文通过质的研究方法,分析出影响中学化学教学中情感态度价值观教学目标实施的因素,并提出一些促进中学化学情感态度价值观教学目标有效落实的策略。     

体验新课程人教版化学必修模块中开放性作业

开放性作业能实现新课程"自主、探究、合作"积极学习方式的目标,培养学生信息处理、观察、探究、创新、交流合作等能力,达到知识与技能、过程与方法、情感态度与价值观和谐发展.主要介绍人教版化学必修模块开放性作业形式,实施情况,目前遇到困难及采取的策略.     

化学史融入课堂教学的价值和策略

化学史本身具有知识广阔性、学科交叉性、可探究性及开放性等特点。将化学史融入课堂教学, 有利于从历史的角度把握化学本质, 也有利于课程标准提出的"知识与技能""过程与方法""情感态度与价值观"三维目标的实现。在化学教学中融入化学史可以采用常用的HPS教学模式或重构的多元教学模式。     

中学化学教学中达成情感态度与价值观目标的途径

诠释了中学化学学科中情感态度与价值观目标,提出了创设智慧的课堂教学、开展丰富的课后拓展和实施多元的学业评价是中学化学教学中达成情感态度与价值观目标的重要途径。     

科学渗透情感态度与价值观目标

正确理解初中化学教学中的“情感态度与价值观”目标,必须把握其内容、特点以及与学科德育目标的联系和区别;全面达成情感态度与价值观目标,必须优化教学过程并准确设计、科学渗透课时情感态度与价值观目标。     

校园环境质量监测实践课程的实施与体会

校园环境质量监测实践课程是一门实践性很强的综合性实践课程。课程目标既有知识与技能目标,又有过程与方法目标,还有情感、态度和价值观目标。为了较好地达成课程目标,既要制定合理的实施方案,又要执行严格的实施过程。指导教师要做好集体备课、课前动员、分组指导、成绩评定和课后总结的每一个环节。     

Interpretation of inorganic arsenic metabolism in humans in the light of observations made in vitro and in vivo in the rat

The toxicity of inorganic trivalent arsenic for living organisms is reduced by in vivo methylation of the element. In man, this biotransformation leads to the synthesis of monomethylarsonic (MMA) and dimethylarsinic (DMA) acids, which are efficiently eliminated in urine along with the unchanged form (As_i). In order to document the methylation process in humans, the kinetics of As_i, MMA and DMA elimination were studied in volunteers given a single dose of one of these three arsenicals or repeated doses of As_i. The arsenic methylation efficiency was also assessed in subjects acutely intoxicated with arsenic trioxide (As₂O₃) and in patients with liver diseases. Several observations in humans can be explained by the properties of the enzymic systems involved in the methylation process which we have characterized in vitro and in vivo in rats as follows: (1) production of As_i metabolites is catalyzed by an enzymic system whose activity is highest in liver cytosol; (2) different enzymic activities, using the same methyl group donor (S-adenosylmethionine), lead to the production of mono- and di-methylated derivatives which are excreted in urine as MMA and DMA; (3) dimethylating activity is highly sensitive to inhibition by excess of inorganic arsenic; (4) reduced glutathione concentration in liver moderates the arsenic methylation process through several mechanisms, e.g. stimulation of the first methylation reaction leading to MMA, facilitation of As_i uptake by hepatocytes, stimulation of the biliary excretion of the element, reduction of pentavalent forms before methylation, and protection of a reducing environment in the cells necessary to maintain the activity of the enzymic systems.     

茶叶中高氯酸盐检测方法研究进展

茶叶中新型污染物高氯酸盐在近年来受到越来越多的关注,相应的检测技术也在不断加强.参考国内外文献,综述了茶叶中高氯酸盐的检测方法.目前,茶叶中高氯酸盐的检测方法主要有离子色谱法（IC）、离子色谱-质谱法（IC-MS）和高效液相色谱-串联质谱法（LC-MS-MS）.比较了不同检测方法的局限性和优越性,重点比较了高效液相色谱-串联质谱法不同前处理方法、净化小柱和检测条件的优劣,对茶叶高氯酸盐检测技术的发展和研究进行了展望,为检测茶叶中高氯酸盐的新材料研发和检测新标准的建立提供理论依据.     

成都西部金马地区土壤微量元素特征研究

对成都平原西部金马镇深层土壤取样分析,研究了具有指示意义的几种微量元素富集情况,揭示了土壤原生地球化学环境质量;通过异常信息的筛选,分析了各元素异常反映的地球化学及地质信息.     

Production of radicals in the ozonolysis of propene in air

Radical production in the ozonolysis of propene in air was monitored directly by a peroxy radical chemical amplification (PERCA) instrument at room temperature (298±2 K) and atmospheric pressure (1×105 Pa). The ozonolysis reactions were conducted in a flow tube under pseudo-first-order conditions for ozone. The decay in ozone was calculated based on reaction time tr and effective rate constant keff (keff = k1[C3H6]0)) for the ozone-propene reaction. The total radical yields relative to consumed ozone were d...     

超临界流体萃取技术在提取中药挥发油中的应用

用超监介CO2流体萃取技术对多种中药挥发油的提取进行了综述,并将其与传统的水蒸馏法进行比较。结果表明,用超临界流体法不仅挥发油的收率高,而且提取时间也大大缩短。     

Formation of disperse ferromagnetic nanoparticles in zeolites in the course of thermal activation in oxygen

Samples of synthetic high-silica zeolites after high-temperature activation in oxygen are studied by ferromagnetic resonance. Observation of the fine structure of ferromagnetic resonance (FMR FS) indicates the formation of magnetic iron oxide nanoparticles in the course of thermal treatment of zeolites in oxygen. Features of the formation of a dispersed ferromagnetic phase in zeolites, geometric and magnetic characteristics of constituent nanoparticles are discussed.     

ICP-AES测定铀污染土壤植物中铀的研究

采用电感耦合等离子体发射光谱(ICP-AES)对铀污染土壤植物中铀的测定方法进行了研究.在λU385.958 nm处,选择了仪器的最佳工作条件,考察了酸度和常见共存元素对测定的干扰情况,并且对比了干灰化消解和湿式消解对测定的影响.研究发现2%硝酸溶液为最佳介质,干扰离子对测定没有显著影响,干灰化消解比湿式消解得彻底.在选定条件下,方法检出限为0.18 mg·L-1,测定下限为0.61 mg·L-1,5.0000 mg·L-1的铀标准溶液的相对标准偏差RSD(n=10)为0.81%,方法回收率为96.2%～106.2%.该方法操作简单,快速.结果表明,用ICP-AES测定铀污染土壤植物样品中的铀是可行的.     

测定血清中Na 含量不确定度的评定

对血清中Na离子含量的测量不确定度进行评定。不确定度的来源主要包括Na离子标准工作液的配制过程、血清样品的定容消化制备、标准曲线拟合、钠离子各分量不确定度的合成等引入的不确定度计算出各分量的不确定度,通过合成得到测量结果的合成不确定度、扩展不确定度及测试结果的报告形式。     

Photoisomerisation in single molecules of nitroprusside embedded in mesopores of xerogels

Photoswitchable hybrid materials are successfully prepared by embedding guanidinium nitroprussides (GuNP, (CN₃H₆)₂[Fe(CN)₅NO]) into mesopores of transparent xerogel monoliths. The such prepared hybrid materials exhibit a higher photostability than the corresponding GuNP solutions, whereby the chemical stability of the [Fe(CN)₅NO]²⁻-anion in titania gel is nearly infinite. By irradiation with light in the blue-green spectral range one nitrosyl isomer is formed by a 180° rotation of the NO ligand changing the Fe–NO into a Fe–ON coordination (SI), which is detected by the shift of the ν(NO) stretching vibration from 1945 cm⁻¹ (Fe–NO) to 1820  cm⁻¹ (Fe–ON). Consequently there is enough space around the NO-ligand for such movement in xerogel mesopores. The embedding in silica xerogels increases the achievable population of the isomeric nitrosyl configuration to about 15% with respect to a single crystalline powder where only 9% are reached.     

鸡肉中兽药残留检测技术研究进展

鸡肉中兽药残留检测是食品安全检测关注的热点,作为目前普遍发展的样品前处理技术,超临界流体萃取、加速溶剂萃取、毛细管固相微萃取及其与色谱质谱联用检测兽药残留受到广泛关注。以鸡肉为主要检测基质对这些新技术的基本原理、特点及在兽药残留分析中的应用进行了综述,同时对兽药残留分析的研究方向进行了展望。