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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.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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