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1.
1)THERMODYNAMICS,KINETICS,AND STRUCTURAL CHEMISTRY(chemical equilibrium and thermodynamic parameters,calorimetry,nonequilibrium thermodynamics and dissipative structure,statistical thermodynamics,macrokinetics,molecular dynamics,ultrafast dynamics,excited states,solution chemistry,complex fluids,solution structure,atmospheric chemistry,dynamic structure,molecular structure,bulk structure,clusters,spectroscopy)2)THEORETICAL AND COMPUTATIONAL CHEMISTRY(quantum chemistry,statistical mechanics.simulation methods and application,computational chemistry,chemical informatics)  相似文献   

2.
蒙古蒿精油化学成份的研究I.   总被引:1,自引:0,他引:1  
The chemical constituents of the essential oil from the leaves of artemisia mongolica Fisch. were separated by gas chromatography employing glass capillary eolumns and identified by GC-MS-COM. 30 components have been separated and identified, i.e. 2-methyl-2-butene, methylene cyclopentane, 7,7-dimethyl-3-methylen-bicyclo-(3, 1, 1) heptane, α-thujene, α-pinene, camphene, 1-octen-3-o1, β-thujene, β-pinene, α-phellandrene, bornylene, p-cymene, terpinen-1-o1, artemisia ketone, γ-terpinene, β-terpineol, 3,7,7-trimethyl-bicyclo-(3, 1,1)-2-heptanol, α-terpinolene, verbenone, linalool iso-thujone, thujone, camphor, isopulegone, isoborneol, terpinen-4-o1, α-terpineol, myrtenol, trans- carveol, cis-carveol.  相似文献   

3.
Multivalent metal-sulfur(M-S,where M=Mg,Al,Ca,Zn,Fe,etc.)batteries offer unique opportunities to achieve high specific capacity,elemental abundancy and cost-effectiveness beyond lithium-ion batteries(LIBs).However,the slow diffusion of multivalent-metal ions and the shuttle of soluble polysulfide result in impoverished reversible capacity and limited cycle performance of M-S(Mg-S,Al-S,Ca-S,Zn-S,Fe-S,etc.)batteries.It is a necessity to optimize the electrochemical performance,while deepening the understanding of the unique electrochemical reaction mechanism,such as the intrinsic multi-electron reaction process,polysulfides dissoluti on and the in stability of metal an odes.To solve these problems,we have summarized the state-of-the-art progress of current M-S batteries,and sorted out the existing challen ges for different multivalent M-S batteries according to sulfur cathode,electrolytes,metallic an ode and current collectors/separators,respectively.In this literature,we have surveyed and exemplified the strategies developed for better M-S batteries to strengthen the application of green,cost-effective and high energy density M-S batteries.  相似文献   

4.
第二、培養基的條件培養基的功用,一方面是供给菌種生长的需要,另一方面是供给菌種综合产品的原料。其成分可分为两類:第一類为炭水化物,如糖飴,玉黍粉,麥粉,馬鈴薯,紙漿废液,葡萄糖等。這些是酒精,丙酮戊醇,构椽酸,酵母等工業的重要原料。其功用是供给微生物生长的能(Energy)。第二類成分是蛋白性的材料如酪素,玉黍浆(Corn steep)粟米,蛋清,鱼肉,肉膏,蛋白脒,  相似文献   

5.
采用ICP—AES法同时测定黑豆和红小豆中Na,Sn,Ca,Zn,Cu,Mg,Al,Fe,P,K,Si,Se,Ba,Mn,M015种元素含量,并对各元素进行了加标回收实验,黑豆和红小豆中各元素的平均回收率在93.11%~102.15%,相对标准偏(RSD)在0.83%0~2.8%,检出限介于0.11~14.09Fg/L。建立了简便、快速、准确和稳定的测定黑豆和红小豆中元素的测定方法。结果显示在黑豆和红小豆中K,Ca,P,Mg,Mn,Fe,Zn等常量元素和微量元素含量较高。红小豆中Ca,Mg,Fe,Zn等营养元素的含量较黑豆中的高。  相似文献   

6.
分析研究了不同粒径分布的石油焦成浆性及制备水焦浆的流变性和稳定性。结果表明,石油焦的成浆性较好,成浆浓度近70%,浆体的表观黏度均随浓度的增大而增大。粒径分布越宽,越有利于堆积,堆积效率越高,可制浆浓度越高,制备水焦浆的最佳药剂量越低,采用萘系分散剂制备的水焦浆呈胀塑性流型,粒径分布越宽,胀塑性越弱,利用静置观察法与Turbiscan Lab稳定性分析仪测定相结合评价水焦浆的稳定性,水焦浆的稳定性差,且粒径越大,析水率越低,沉降区的焦粉颗粒越易发生聚结,底部越易产生硬沉淀,稳定性越差。颗粒聚结是水焦浆稳定性的主要影响因素。  相似文献   

7.
报道三种不同类型的气相色谱用氦直流等离子体离子化检测器。以氦气为载气和工作气体, 白金电极为放电电极, 通过测量检测器的工作参数, 考察了检测器对H2, O2, Ar, N2, CH4, CO, CO2等永久气体的响应特性及分析性能, 并应用于实际样品分析。对检测器的离子化机理进行了研究和探讨。  相似文献   

8.
《化学研究》2012,(5):F0002-F0002
河南大学化学化工学院是河南大学成立较早、规模较大的院系之一,始建于1923年,重建于1959年,时称化学系,Ig85年设立工科,1989年改称化学化工系,1995年更名为化学化工学院。学院现有教职工111人,其中国务院特殊津贴获得者1名,省优秀专家2名,校特聘教授4名,博士生导师6名,硕士生导师71名,教授、副教授67名,具有博士学位教师48G。  相似文献   

9.
A series of novel phenylpyrazole carboxylic acid derivatives containing fluorine moiety,i.e.,diamides 11,simple aryl-bearing amides 12 and acylthioureas 14 were successfully synthesized based on the key fluo ro-containing phe nylpyrazole acid intermediate.The new compounds were identified and confirmed by melting point,1H NMR,13C NMR and elemental analysis or HRMS.The bioassay results indicated that some of the compounds possessed excellent insecticidal activities towards oriental armyworm,diamondback moth and corn borer at low concentrations.For examples,compounds 11a,11e-g and 14b exhibited remarkable larvicidal activities with LC50 values of 0.13-0.39 mg/L and 0.0002-0.0014 mg/L against oriental armyworm and diamondback moth,respectively,were comparable with those of the control chlorantraniliprole.Particularly,lie were found superior to chlorantraniliprole in oriental armyworm tests(LC50:0.23 mg/L vs.0.26 mg/L);11a,lie,11f and 14c in diamondback moth tests with LC50 values of 0.0002 mg/L,0.0002 mg/L,0.0008 mg/L and 0.0005 mg/L,respectively,we re more effective than that of chlorantraniliprole.In addition,12 a also showed a promising insecticidal potential and development/optimization advantage.Compounds 11a,lle-g,12a,14b and 14c could be considered as possible new leading structures for further study.The SAR investigation indicated that the compounds with fluorine motif(e.g.,-F,-CF2H,-CF3)held apparently favorable insecticidal potentials,which provided useful guidance for further design/development of new phenylpyrazole-containing agrochemicals.  相似文献   

10.
An aminophenol ligand, N,N,N'-tri(2-hydroxy-5-methylbenzyl)-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffract...  相似文献   

11.
高等师范化学专科素质教育研究   总被引:4,自引:0,他引:4  
高等师范化学专科教育是较高层次的素质教育,必须转变思想,更新观念,深化改革,确立以培养创新能力为核心的素质教育目标,将目标纳入课程,构建新课程体系,课程内容素质教育化,教学方法和手段现代化。采取有力措施,优化结构,建设一支高素质的教师队伍是实施素质教育的基本保证。要为素质教育创造良好宽松的外部和内部环境条件。  相似文献   

12.
2012年将迎来中国化学会80华诞。1932年,化学界的前辈们怀着拳拳爱国之心,抱着科学救国之志,自愿组成了这个学术团体。他们以民族大业为己任,对发展我国的化学化工和化学教育,做出了卓绝的贡献。在其后不到两年,本刊就作为中国化学会主办的学术刊物正式问世。忆往昔,岁月峥嵘,看今朝,前景辉煌。  相似文献   

13.
刘敬华  何志民 《化学教育》2007,28(10):49-49
“铁丝在氧气中燃烧”是初中化学教材中证明氧气化学性质的一个演示实验,该实验证明了氧气比较活泼,在一定条件下可以和金属发生剧烈反应。但是与木炭在氧气中燃烧、硫在氧气中燃烧、蜡烛在氧气中燃烧的演示实验相比,铁丝在氧气中燃烧的实验存在着一些不足的地方,针对这些不足,对铁丝在氧气中燃烧的实验进行了改进。1实验存在的问题按照教材要求,铁丝在氧气中燃烧的实验,须将铁丝绕成螺旋状,并在铁丝的末端绑上一根火柴杆,实验时先将火柴杆点燃,待火柴杆将燃尽时,迅速伸入盛满氧气的集气瓶中。这样的操作存在2个问题:第一,火柴燃烧的程度不…  相似文献   

14.
若缺铁,生贫血,减智力,得痴呆,肝脾肿,无神色,诸细胞,易能缺,一缺乏,肤变白,早治疗,速收效,食疗法,是先决.其一法:取生铁,一百克,先净后,加大枣,放二两,入水煮,去生铁,喝完汤,将大奉,随身装,时时吃,日一剂,二月愈.  相似文献   

15.
Over the past decade,structural DNA nanotechnology has been well developed to be a promising and powerful technique to generate various nanostructures with programmability,spatial organization and biocompatibi-lity.With the advent of computer-aided tools,framework nucleic acids have been employed in a series of biomedical applications,ranging from biosensing,bioimaging,diagnosis,to therapeutics.In this review,we summarized recent advances in the construction of precisely assembled DNA nanostructures,and DNA-engineered biomimetics.We also outlined the challenges and opportunities for the translational applications of framework nucleic acids.  相似文献   

16.
在水热条件下(120 ℃),将醋酸锰、4,4'-联吡啶(4,4'-bpy)与9-蒽酸(9-HAC)反应,得到了配位聚合物[Mn(9-AC)2(4,4'-bpy)(H2O)2]n,通过元素分析、红外光谱、X射线单晶衍射对其进行了表征,并用TGA研究了该配位聚合物的热稳定性.结构解析结果表明,该晶体属于正交晶系,Fdd2空间群,a=1.66772(12) nm,b=3.36471(16) nm,c=1.1687(4) nm,V=6.558(2) nm3,Z=8,M -r=689.60,Dc=1.397 Mg/m3,R=0.0356,wR2 = 0.0604.在该配位聚合物中,中心锰原子采取略微变形的八面体构型,与两种配体共同构筑了一维直线形链结构,链与链之间通过氢键相互作用构筑成三维超分子网络.  相似文献   

17.
以哈密热解焦油重质馏分悬浮床加氢裂化后的轻质油为原料,对其性质进行了分析,轻质油保留了煤的基本单元结构特点,富含芳烃类和环烷烃类化合物,氮含量较高;采用200 mL固定床精制-裂化串联装置,对轻质油原料进行了加氢裂化制取石脑油的研究;反应压力15 MPa下,考察了不同温度对加氢裂化反应的影响。结果表明,适宜的裂化段温度为390℃,此温度下,180℃馏分转化率为53.69%,氢耗5.13%,180℃石脑油收率56.8%,裂化后石脑油主要以C_(6-9)类烃类物质为主,其中,环烷烃含量为71.99%,芳烃含量3.13%,芳潜值70.1;以最佳工艺条件下产出裂化石脑油为原料,进行了催化重整制取BTXE的研究,采用石油系中间基石脑油作为对比,裂化石脑油重整后BTXE类物质总产率为55.85%,较石油基石脑油生成量高25.53%,彰显了煤基油的优势和特点,验证了煤热解重油裂化石脑油是制取BTXE类物质良好的原料。  相似文献   

18.
本文应用加压原位(in-situ)核磁共振技术, 在反应温度70-75℃, 压力1.0-2.0MPa, 氘代苯为溶剂, 偶氮二异丁腈(AIBN)为引发剂的条件下探索了磷化氢与丙烯腈, 4-乙烯基吡啶, 烯丙基胺, 丙烯酰胺, 氨基吡啉和N-乙烯基咔唑的自由基加成反应, 结果表明除氨基吡啉之外的其它五种含氮化合物均能与磷化氢发生反应, 从而找到合成含氮有机膦的良好路线。  相似文献   

19.
洪琳  杨克 《化学学报》1987,45(12):1207-1210
二乙基膦酰乙酸乙酯阴离子与对硝基苄基衍生物的反应中发生烷基化和烷氧基化.结果表明,离去基团的离去性能降低,SN2烷基化或烷氧基化受抑制,而是有利于SRN 1途径,使烷基化容易发生.在对硝基苄基氯化物与阴离子反应时,得到P,P'-二硝基苯代乙烯,当不存在电子转移抑制剂或只存在间二硝基苯时,二苯代乙烯通过SRN 1机理形成,在对二硝基苯时,以SN 2消除反应机理.  相似文献   

20.
铜在氯气中燃烧的实验改进   总被引:2,自引:0,他引:2  
李铜  罗世翠 《化学教育》2011,32(10):83-83
本实验按课本要求进行,具有操作简便、现象明显、成功率高等优点。但不足之处是:若同年级平行班级多,在课前要制备大量Cl2,耗时长又不易保存。此外,实验时难免将集气瓶中的Cl2飘逸到室内,污染教室环境,不利于师生健康。为此,笔者经反复探索,将该实验进行了如下改进。实验操作简单、现象更明显,缩短了实验时间,效果很好,克服了以上不足之处。  相似文献   

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