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1.
为适应山东省初中化学教学改革的需要1989年山东省教学研究室以国家教委颁发的《九年制义务教育全日制中学化学教学大纲(初审稿)》为依据,组织人员编写了一套面向山东省大多数地区的义务教育化学试验教材。几年来,在教材的编写、试验和修订过程中,我们深深地感到初中化学教材的编写如何适应义务教育的新形势、新任务和新要求,是值得认真研究和探讨的问题。下面结合山东省义务教育化学试验教材的编写,就义务教育化学教材编写中的几个问题谈谈我们的看法。  相似文献   

2.
国内外初中化学教材编写的比较研究   总被引:5,自引:2,他引:3  
钱扬义  王祖浩 《化学教育》2003,24(3):8-11,48
选取国内外有代表性的初中化学教材作为范例,从教材设计的背景中对教材编写理念、教材内容选取、教材内容组织方式、教材栏目和版面设计以及化学实验和习题设计等方面进行比较,并从5个维度得出现行国内外初中化学教材编写的共同特点。  相似文献   

3.
原子是初中化学课程的重要知识内容,是初中学生学习的重点和难点之一,不同的教材内容和编排对学生的学习有着不同的效果。本文从内容体系、编写思路、呈现方式3个方面对中国和德国的4种初中化学教材中“原子”的编写进行比较。  相似文献   

4.
江家发  葛秋霖 《化学教育》2018,39(23):19-24
通过对俄罗斯现行初中化学教材的分析,总结该教材在处理综合性内容与化学学科内容的关系,自然科学知识与社会科学知识的内在联系,以及化学与社会等相关问题上的设计方法和可取经验,并由此对我国初中化学教材的编写提出建议。  相似文献   

5.
殷志忠  倪娟  陈强 《化学教育》2013,34(12):6-9
金属与金属矿物是初中化学重要的学习内容。本文就这部分内容对德国教材与国内上教版义务教育教科书《化学》进行比较,并提出德国教材给我们的启示,以期为我国的教材编写提供借鉴,也为一线教师的教学提供建议。  相似文献   

6.
我校接受国家教委的委托,承担了“五·四”学制教育试验和编写“五·四”学制初中化学教材的任务。从1985年以来,我们一面进行学制试验,一面根据九年制义务教育的要求,对化学教材的编写作出构想,并把我们的初步构想放到教育试验中去检验。目前初中化学教材第一册(包括与之配套的化学实验教材、习题册)已经出版,第二册(包括与之配套的教材)也将于今年6月出版,并同时出版第一册和第二册的教学参考书。下面对这套教材作一简单的介绍。  相似文献   

7.
我国大陆和台湾的化学(科学)教材在化学启蒙方面的内容编写有着各自的特点和优势,因此以我国大陆人教版初中《化学》与我国台湾康轩文教版《自然与生活科技》为例,通过问卷调查法与对比分析法,研究化学启蒙阶段的学生对待化学的态度以及海峡两岸教材中“实验”“插图”“科普知识”等3部分内容的设置差异。结果表明:(1)化学实验是启蒙阶段学生对化学感兴趣的起始点,也是初接触时的难点,其中以我国台湾《自然与生活科技》教材中化学实验的探究性及层次性更深;(2)化学启蒙阶段教材中插图的科学性、清晰度以及精美程度对学生学习化学的兴趣和态度有较大影响;(3)化学教材中的模型图实物化有助于学生拨云见日,了解化学的真实模样。  相似文献   

8.
初中化学基本概念学法指点   总被引:1,自引:0,他引:1  
艾银寿 《化学教育》1995,16(7):23-24
化学基本概念是初中化学教学内容的重要组成部分。因此,学生必须扎实地掌握化学基本概念,才能真正学好化学。考虑到许多化学概念在教材中集中出现,对于刚接触化学的初中生来说,学习时往往感到困惑。  相似文献   

9.
傅丰昌 《化学教育》1992,13(2):9-10
初中化学教学是化学教育的启蒙阶段,着眼于提高全民族的素质,以社会主义公民在劳动、学习和生活中所必需的化学基础知识教育学生,培养基本技能和能力,为学生参加社会主义建一设和进一步学习现代科学技术打好初步基础。  相似文献   

10.
通过对人教版义务教育教科书《化学》和俄罗斯现行Габриелян(加布里耶利亚)版本初中化学教材的金属相关知识进行内容结构、知识构成、实验与探究活动等方面的比较,对我国的教材编写提出反思与建议。  相似文献   

11.
The reactions of N-substituted hydroxylamines with alkenals serve as a method for the synthesis of the corresponding 2-substituted 3(5)-hydroxyisoxazolidines. The reaction pathway is determined by the nature of the substituent attached to the nitrogen atom. Ring-chain isomerism has been detected in these newly obtained compoundsTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1270–1276, September, 1987.  相似文献   

12.
Triazenide [M(eta2-1,3-ArNNNAr)P4]BPh4 [M = Ru, Os; Ar = Ph, p-tolyl; P = P(OMe)3, P(OEt)3, PPh(OEt)2] complexes were prepared by allowing triflate [M(kappa2-OTf)P4]OTf species to react first with 1,3-ArN=NN(H)Ar triazene and then with an excess of triethylamine. Alternatively, ruthenium triazenide [Ru(eta2-1,3-ArNNNAr)P4]BPh4 derivatives were obtained by reacting hydride [RuH(eta2-H2)P4]+ and RuH(kappa1-OTf)P4 compounds with 1,3-diaryltriazene. The complexes were characterized by spectroscopy and X-ray crystallography of the [Ru(eta2-1,3-PhNNNPh){P(OEt)3}4]BPh4 derivative. Hydride triazene [OsH(eta1-1,3-ArN=NN(H)Ar)P4]BPh4 [P = P(OEt)3, PPh(OEt)2; Ar = Ph, p-tolyl] and [RuH{eta1-1,3-p-tolyl-N=NN(H)-p-tolyl}{PPh(OEt)2}4]BPh4 derivatives were prepared by allowing kappa1-triflate MH(kappa1-OTf)P4 to react with 1,3-diaryltriazene. The [Os(kappa1-OTf){eta1-1,3-PhN=NN(H)Ph}{P(OEt)3}4]BPh4 intermediate was also obtained. Variable-temperature NMR studies were carried out using 15N-labeled triazene complexes prepared from the 1,3-Ph15N=N15N(H)Ph ligand. Osmium dihydrogen [OsH(eta2-H2)P4]BPh4 complexes [P = P(OEt)3, PPh(OEt)2] react with 1,3-ArN=NN(H)Ar triazene to give the hydride-diazene [OsH(ArN=NH)P4]BPh4 derivatives. The X-ray crystal structure determination of the [OsH(PhN=NH){PPh(OEt)2}4]BPh4 complex is reported. A reaction path to explain the formation of the diazene complexes is also reported.  相似文献   

13.
14.
Conclusions The mass and NMR spectra of haplophyllidine, perforine, and their derivatives have been studied. The influence of the open and cyclic forms of the molecular ion on the nature of the fragmentation has been discussed. The main routes of fragmentation of the compounds considered are due to the presence of substituents at C8 and C4.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 4, pp. 273–279, 1969  相似文献   

15.
The values of activation parameters in uncured and cured epoxy resins, rubbers, and blends thereof are investigated. The dependences of activation energy and adhesion strength of epoxy-rubber compositions on rubber content are determined. The correlation of adhesion and activation energy values for polyurethane rubber and epoxy-rubber compositions is shown.  相似文献   

16.
Aroyl- and acetylhydrazones of acet- (I) and benzaldehydes (IV) and benzoylhydrazones of acet- (II) and benzaldehydes (III) were studied by x-ray structural and quantum-chemical methods in order to establish their structures. Compund (I) was the EEZ structure in the crystal. Calculations and spectral data showed that the EEE form occurs in nonpolar solvents and in the gas phase. According to crystallographic data molecules (I)–(IV) are the E-isomers (relative to the N-N bond) and the hydrazone fragments are planar. Intermolecular N-H...O H-bonds from in the crystals. The data obtained suggest that the majority of acylhydrazones are conformationally rigid on dissolution although exceptions do occur. Apparently the reasons for the difference of acetyl- and benzoylhydrazones in electrocarboxylation reactions are electronic and not steric factors.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 75–81, January, 1991.  相似文献   

17.
Reaction of the proligand Ph2PN(SiMe3)2 (L1) with WCl6 gives the oligomeric phosphazene complex [WCl4(NPPh2)]n, 1 and subsequent reaction with PMe2Ph or NBu4Cl gives [WCl4(NPPh2)(PMe2Ph)] (2) or [WCl5(NPPh2)][NBu4] (3), respectively. DF calculations on [WCl5(NPPh2)][NBu4] show a W=N double bond (1.756 A) and a P-N bond distance of 1.701 A, which combined with the geometry about the P atom suggests, there is no P-N multiple bonding. Reaction of L1 with [ReOX3(PPh3)2] in MeCN (X = Cl or Br) gives [ReX2(NC(CH3)P(O)Ph2)(MeCN)(PPh3)](X = Cl, 4, X = Br, 5) which contains the new phosphorylketimido ligand. It is bound to the rhenium centre with a virtually linear Re-N-C arrangement (Re-N-C angle = 176.6 degrees, when X = Cl) and there is multiple bonding between Re and N (Re-N = 1.809(7) A when X = Cl). The proligand Ph2PNHNMe2(L2H) reacts with [(C5H5)TiCl3] to give [(C5H5)TiCl2(Me2NNPPh2)] (6). An X-ray crystal structure of the complex shows the ligand (L2) is bound by both nitrogen atoms. Reaction of the proligands Ph2PNHNR2[R2 = Me2 (L2H), -(CH2CH2)2NCH3 (L3H), (CH2CH2)2CH2 (L4H)] with [{RuCl(mu-Cl)(eta6-p-MeC6H4iPr)}2] gave [RuCl2(eta6-p-MeC6H4iPr)L] {L = L2H (7), L3H (8), L4H (9)}. The X-ray crystal structures of 7-9 confirmed that the phosphinohydrazine ligand is neutral and bound via the phosphorus only. Reaction of complexes 7-9 with AgBF4 resulted in chloride ion abstraction and the formation of the cationic species [RuCl(6-p-MeC6H4iPr)(L)]+ BF4- {(L = L2H (10), L3H (11), L4H (12)}. Finally, reaction of complex 6 with [{RuCl(mu-Cl)(eta6-p-MeC6H4iPr)}2] gave the binuclear species [(eta6-p-MeC6H4iPr)Cl2Ru(mu2,eta3-Ph2PNNMe2)TiCl2(C5H5)], 13.  相似文献   

18.
朱劲波  马立群  梁飞  苗迎春  王立民 《应用化学》2015,32(11):1221-1230
Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB5型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。  相似文献   

19.
20.
Chlorine dioxide oxidation of cysteine (CSH) is investigated under pseudo-first-order conditions (with excess CSH) in buffered aqueous solutions, p[H+] 2.7-9.5 at 25.0 degrees C. The rates of chlorine dioxide decay are first order in both ClO2 and CSH concentrations and increase rapidly as the pH increases. The proposed mechanism is an electron transfer from CS- to ClO2 (1.03 x 10(8) M(-1) s(-1)) with a subsequent rapid reaction of the CS* radical and a second ClO2 to form a cysteinyl-ClO2 adduct (CSOClO). This highly reactive adduct decays via two pathways. In acidic solutions, it hydrolyzes to give CSO(2)H (sulfinic acid) and HOCl, which in turn rapidly react to form CSO3H (cysteic acid) and Cl-. As the pH increases, the (CSOClO) adduct reacts with CS- by a second pathway to form cystine (CSSC) and chlorite ion (ClO2-). The reaction stoichiometry changes from 6 ClO2:5 CSH at low pH to 2 ClO2:10 CSH at high pH. The ClO2 oxidation of glutathione anion (GS-) is also rapid with a second-order rate constant of 1.40 x 10(8) M(-1) s(-1). The reaction of ClO2 with CSSC is 7 orders of magnitude slower than the corresponding reaction with cysteinyl anion (CS-) at pH 6.7. Chlorite ion reacts with CSH; however, at p[H+] 6.7, the observed rate of this reaction is slower than the ClO2/CSH reaction by 6 orders of magnitude. Chlorite ion oxidizes CSH while being reduced to HOCl, which in turn reacts rapidly with CSH to form Cl-. The reaction products are CSSC and CSO3H with a pH-dependent distribution similar to the ClO2/CSH system.  相似文献   

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