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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.
若缺铜,人早衰,细胞损,骨质败,既愚蠢,又笨傻,男变疯,女变呆,多贫血,多畸形,冠心病,又多患,易病危,易得癌,常见病,白癜风,胆固醇,速高升,应早治,不徘徊,食疗法,喜开怀.  相似文献   

6.
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   

7.
专利     
《化学分析计量》2012,(2):65+74
一种不锈钢样品全元素分析方法公开号:CN102359972A公开日:2012.02.22申请人:山西太钢不锈钢股份有限公司一种不锈钢样品全元素分析方法,属于冶金分析领域,它分别用直读光谱法和X射线荧光法分析C,Si,Mn,P,S,Cu,Al,Mo,V,Ti,Co,As,Sn,Pb元素,将直读光谱法分析结果与X射线荧光法分析结果进行相关性处理,在X射线荧光分析仪中添加C,Si,Mn,P,S,Cu,Al,Mo,V,Ti,  相似文献   

8.
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   

9.
Most of the current analytical methods depend largely on laboratory-based analytical techniques that require expensive and bullky equipment,potentially incur costly testing,and involve lengthy detection processes.With increasing requirements for point-of-care testing(POCT),more attention has been paid to miniaturized analytical devices.Miniaturized electrochemical(MEC)sensors,including different material-based MEC sensors(such as DNA-,paper-,and screen electrode-based),have been in strong demand in analytical science due to their easy operation,portability,high sensitivity,as well as their short analysis time.They have been applied for the detection of trace amounts of target through measuring changes in electrochemical signal,such as current,voltage,potential,or impedance,due to the oxidation/reduction of chemical/biological molecules with the help of electrodes and electrochemical units.MEC sensors present great potential for the detection of targets including small organic molecules,metal ions,and biomolecules.In recent years,MEC sensors have been broadly applied to POCT in various fields,including health care,food safety,and environmental monitoring,owing to the excellent advantages of electrochemical(EC)technologies.This review summarized the state-of-the-art advancements on various types of MEC sensors and their applications in POCT.Furthermore,the future perspectives,opportunities,and challenges in this field are also discussed.  相似文献   

10.
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   

11.
Many current food and health trends demand the use of more ecological, sustainable, and environmentally friendly techniques for the extraction of bioactive compounds, including antioxidants. However, extraction yields and final antioxidant activities vary between sources and are highly influenced by the given extraction method and nature and ratio of the employed solvent, especially for total polyphenols, flavonoids, and anthocyanins, which are well recognized as natural antioxidants with food applications. This review focused on the most common extraction techniques and potential antioxidant activity in the food industry for various natural antioxidant sources, such as green tea, rosemary, clove, and oregano. Green extraction techniques have been proven to be far more efficient, environmentally friendly, and economical. In general, these techniques include the use of microwaves, ultrasound, high hydrostatic pressure, pulsed electric fields, enzymes, and deep eutectic solvents, among others. These extraction methods are described here, including their advantages, disadvantages, and applications.  相似文献   

12.
The past three decades have witnessed an exponential increase in the structural diversity and applications of dendrimers, spanning across drug delivery and diagnostics, protein, and enzyme mimicry, solubility enhancement, coatings, light harvesting, and catalysis. The dendrimer community has recently focused on internally functionalized dendrimers (IFDs) owing to their advanced design and functionality. The synthesis of IFDs relies on advanced orthogonal chemistries and/or (de)protection schemes, as well as careful purification to minimize polydispersity of composition and molecular weight. The studies published on IFDs, however, lay scattered across the chemical literature, and a comprehensive presentation of structural rationale, synthetic procedures, and technologically relevant applications is missing. To address this need, this review presents a comprehensive collection and discussion of all available studies on IFDs, detailing their methods of synthesis and their structure–function correlations. The wide variety of internal functionalities, including hydroxyl, amine, carboxylic acid, allyl, alkyne, and imidazole groups, enables myriad applications in biochemistry, chemical and biomedical engineering, and material science. Particular focus is given to IFDs that are amenable to modular synthetic strategies, which promote higher synthetic yield and scalability, and therefore possess stronger translational and commercial potential. As such, this review guides research groups pursuing the difficult task of IFD rational design and synthesis providing them a concise roadmap to their mission.  相似文献   

13.
The paper-based sensing devices have drawn a broad interest in analytical chemistry for colorimetric and fluorescent-based analysis of biological, environmental, clinical, and food samples. It is due to the simple, rapid, biodegradable, user-friendly, less expensive, and low waste generation into the environment. Here, the recent development of paper-based sensors fabricated with different noble metal nanoparticles (NPs) and semiconductor and carbon quantum dots (QDs) is demonstrated to analyze several chemical substances from various samples. User-friendly and portable recording devices such as digital cameras, smartphones, scanners, etc. along with color detecting softwares are employed to measure the color intensity of nanomaterials fabricated paper devices after the deposition of a sample solution containing various chemical substances. The advantages and disadvantages of incorporating nanomaterials in the paper substrate (direct deposition, inkjet printing, screen printing and wax printing) are illustrated. The mechanism for colorimetric, fluorescence, phosphorescence, and chemiluminescence sensing using noble metal NPs (Ag, Cu, and Au), semiconductors, and carbon QDs for the determination of metal ions, anions, pesticides, biomolecules, and other toxic chemical substances are discussed. Thus, this review article would be highly useful for scientists and researchers to design colorimetric sensors to monitor chemical toxicants in clinical, environment, foods, and many other related samples.  相似文献   

14.
生物光化学   总被引:2,自引:0,他引:2  
蒋丽金 《有机化学》1983,3(2):83-91
生物光化学研究光在动植物体内所引起的生化现象。例如:经过各种不同波长的光辐照后的生命现象,生长规律,某些生理和病理过程,疾病的产生和治疗机理,细胞的辐射损伤和自然防御,以及光合色素在生物进化中的作用等。本文就光引起的现象:视觉、生物钟(光周期性)、植物的光合作用、辐射损伤及其修复、牛皮癣的治疗、新生儿黄疸病的治疗机理,以及光合色素——藻胆蛋白等七种现象,做了综述性的介绍。  相似文献   

15.
三唑类化合物作为药物广泛应用于临床,是目前药物研究开发的重点领域之一.越来越多的高活性、低毒性、不良反应少、多药耐药性小、生物利用率高、药代动力学性质好、药物靶向性强、给药方式多样化、广谱、高疗效的三唑类化合物作为候选药物或药物用于临床医治多种疾病,显示出了三唑类化合物在医药领域的巨大开发价值和潜在的宽广应用.本文结合自己的工作,参考国内外近五年文献系统地综述了三唑类化合物作为药物在整个医药领域的研究与开发近况,包括抗真菌、抗细菌、抗结核、抗癌、抗病毒、抗炎镇痛、抗惊厥等,并展望其发展趋势与前景.希望该评论有助于为高活性低毒性三唑类医药合理设计提供新思路.  相似文献   

16.
PP/clay composites with different dispersions, namely, exfoliated dispersion, intercalated dispersion and agglomerates and particle-like dispersion, were prepared by direct melt intercalation or compounding. The effect of clay dispersion on the crystallization and morphology of PP was investigated via PLM, SAXS and DSC. Experimental results show that exfoliated clay layers are much more efficient than intercalated clay and agglomerates of clay in serving as nucleation agent due to the nano-scale dispersion of clay, resulting in a dramatic decrease in crystal size (lamellar thickness and spherulites) and an increase of crystallization temperature and crystallization rate. On the other hand, a decrease of melting temperature and crystallinity was also observed in PP/clay composites with exfoliated dispersion, due to the strong interaction between PP and clay. Compared with exfoliated clay layers, the intercalated clay layers have a less important effect on the crystallization and crystal morphology. No effect is seen for samples with agglomerates and particle-like dispersion, in regard to melting temperature, crystallization temperature, crystal thickness and crystallinity.  相似文献   

17.
Purification and properties of three cellobiases from Aspergillus niger A20   总被引:1,自引:0,他引:1  
Three cellobiases, here called cellobiase A, B, and C, from the culture filtrate of Aspergillus niger A20, were purified by precipitation with ammonium sulphate, gel filtration through Sephadex G-75, and column chromatography of DEAE-cellulose. The purified enzymes were homogeneous on polyacrylamide disk electrophoresis. The mol wt of the purified enzymes were estimated by SDS-gelelectrophoresis to be 88,000, 80,000, and 71,000 for cellobiases A, B, and C, respectively. The enzymes were active at pH 4.5 and 55–60°C. The pattern of their aminoacid compositions showed high contents of aspartic acid, glutamic acid, threonine, serine, and glycine. The apparent Km values for cellobiose were 0.9, 1.63, and 1.0 mM for cellobiases A, B, and C, respectively. Calcium ions stimulated cellobiases B and C, and Co2+ and Mg2+ ions stimulated cell obiase A. The purified enzymes hydrolyzed cellobiose and aryl-β-d-glucosides, but they had no action on sucrose, maltose, and cellulose. The three cellobiases catalyzed transglycosylate reaction, and the major product formed from cellobiose was tetramer of glucose.  相似文献   

18.
石墨烯纤维是一种由石墨烯片层紧密有序排列而成的一维宏观组装材料。通过合理的结构设计和可控制备,石墨烯纤维能够将石墨烯在微观尺度的优异性能有效传递至宏观尺度,展现出优异的力学、电学、热学等性能,从而应用于功能织物、传感、能源等领域。目前,石墨烯纤维主要通过湿法纺丝、限域水热组装等方法制备得到,其性能可以通过对材料体系和制备工艺的优化而进一步提升。本文首先介绍了石墨烯纤维的制备方法,然后详细阐述了石墨烯纤维的性能,讨论了其性能提升策略,并总结了石墨烯纤维的应用,最后对石墨烯纤维的未来发展、挑战和前景进行了展望。  相似文献   

19.
Natural 1,5-di-, 1,4,5-tri-, and 1,4,5,8-tetrahydroxyanthraquinones and their anions and metal complexes were shown to be equilibrium mixtures of tautomers and conformers using quantum-chemical and correlation analysis of elecronic absorption spectra. Solvent effects, ionization, complexation, and the introduction and substitution of substituents were accompanied by shifts of tautomeric and conformational equilibria that determine the color of the compounds. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 224–229, May–June, 2006.  相似文献   

20.
在合成气(CO+H2)与复合溶剂(水+有机溶剂)液化系统下研究了气氛、温度、催化剂类型对宝日希勒褐煤转化率、油气水产率和CO转化率等液化特征的影响,从而探讨其液化性能。结果表明,在高含水复合溶剂系统中,合成气气氛、反应温度430-450℃适宜宝日希勒褐煤液化转化,转化率可达到81.15%,油气水产率达到71.53%。该液化系统下,含铁、碱和硫复合型催化剂能有效地提高液化转化率和油气水产率,在430℃催化液化下褐煤转化率达92.27%,油气水产率达79.39%。该催化剂有效促进了煤中大分子的裂解和系统中水煤气变换反应进程,沥青质减少,油含量增多。液化油中多环芳烃衍生物在催化液化过程中向单环芳烃衍生物和烷烯烃转化,分子量降低,提高了油品质量。  相似文献   

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