碳

The invention concerns a process for preparing heterocyclic carbenes of general formula in which R1, R2, R3 and R4 are identical or different and mean saturated or unsaturated, straight-chain, branched or cyclic, unsubstituted or substituted C1-C10 alkyl, C2-C5 alkylidene, C2-C5 alkylidine, C7-C19 aralkyl or C6-C14 alkyl groups, R3 and R4 can also stand for hydrogen or form jointly anellated, substituted or unsubstituted groups with between 3 and 7 carbon atoms and X stands for carbon or nitrogen, R3 being dropped if X is nitrogen.

本发明涉及一种制备通式Ⅰ的杂环碳烯的方法，其中在通式Ⅰ中，R1、R2、R3和R4是相同的或不同的，并且是饱和的或不饱和的，直链、支链或环状的，未取代或取代的C1－C10－烷基、C2－C5－亚烷基、C2－C5－次烷基、C7－C19－芳烷基或C6－C14－芳基基团，R3和R4可以是氢或它们一起形成具有3－7个碳原子的稠合的、取代或未取代的基团，X是碳或氮，并且当X是氮时，不存在R3。

Controlled direct current power supply is gradually applied between anode anode aluminum oxide of aligned carbon nanotubes film and cathode, the experimental data are measured through detecting circuit, which consists of HITACHI oscilloscope and amperemeter.

介绍了一种基于定向纳米碳管的气敏传感器，以生长定向纳米碳管的氧化铝模板作为阳极，铝板作为阴极，利用纳米碳管的尖端发射效应，在较低的电压下使气体产生放电现象。

Because there are many complex factors resulting in concrete cardonated,the experimences of other peoples must be used in line with local conditions and materials other than simply when study on carbonation speed and evaluation of proof carbonification.

由于影响混凝土碳化的因素复杂多变，在研究碳化速度，评价其抗碳化性能优劣时，应因地、因材制宜，不能生套别人的经验。

The results show that isobutene oligomerization is fast liquid-solid reaction. Under the temperature of 80 ℃～120 ℃ and pressure of 2.0 MPa, the products of oligomerization are mainly dimers and trimers of isobutene. The yield of trimers is higher than that of dimers and the mass fraction of trimers decreases with reaction temperature increasing. The yield of tetramers is much lower than that of dimmers and trimers. The tetramers are formed by reaction of isooctenes and C8 carbonium ion.

结果表明，异丁烯齐聚反应为快速液固相催化反应，在80 ℃～120 ℃，2.0 MPa的实验条件下，反应产物主要是异丁烯的二聚物和三聚物，且三聚物的收率远高于二聚物，两者的浓度比值随反应温度的升高而下降；少量四聚物的生成主要源于碳八烯烃与碳八正碳离子的反应。

According to Wurtz reaction, if we can control solvothermal reactive condition to make the four C-Cl bonds in the carbon tetrachloride broken incompletely, according to the mechanism of Wurtz reaction, some kinds of free radicals or carbonium ions will be produced in solvothermal condition.

那么，如果控制反应条件，使四氯化碳等小分子碳氯化合物中的氯原子不完全脱掉，根据Wurtz反应机理，反应体系中将产生大量的碳氯自由基或碳正离子，它们在溶剂热条件下按照一定的生长规律进行组合，必将生成大量的多氯代多环芳香化合物。

By comparative analysis of applicability, we concluded that the microcapsule from sodium alginate used in carbonless copy paper had the same advantages as domestic and foreign抯 in the characteristic of use, stableness and the speed of color development and so on.

证明了以海藻酸钠为壁材单凝聚法制备的无碳复写纸用微囊具有较高的包埋率、不渗透性、稳定性及一定强度；通过应用性的对比分析，认为以海藻酸钠为壁材自制的无碳复写纸用微囊在使用性能、稳定性、显色速度等方面均可达到国内外无碳复写纸的水平。

Based on the discussion of the effect of the refractories on clean steel making, it is concluded that alkali refractories can reduce oxygen and sulfur contents, carbonless or low carbon refractories can suppress carbon pick up of steel; The antihydration property of magnesia calcium system can be improved by surface treatment.

通过耐火材料对纯净钢冶炼影响的讨论，得出发展碱性耐火材料可以脱硫和脱氧、无碳和低碳耐火材料可以抑制增碳、用表面处理的方法可以改善镁钙系耐火材料的抗水化性和合理使用耐火材料可以有效地减少钢中的氢含量的结论

This paper reviews the development of synthetic technology of carbon nanotube by catalytic py-rolysis of carbonous compound and compares the advantages and disadvantages of moving support method and floating catalysis method.

介绍了催化热分解含碳化合物合成碳纳米管的技术，比较了基板法和流动催化法的优缺点以及它们的发展前景，并简单地介绍了碳纳米管的应用领域。

The formation of SEI is related to the structure and BET surface of the carbonous materials. This causes the main irreversible capacity of carbonous electrode at the first charge and discharge cycle. It will play an active ...

初始的充放电循环中在碳材料的表面会形成SEI膜，其形成与碳材料的结构和比表面积有关，并造成碳电极在首次充放电循环时的不可逆容量；稳定的SEI膜一旦形成，在随后的充放电循环中将对电极的循环稳定性产生积极作用。

The SEI film on the surface of three kinds of carbonous materials: Mesocarbon Microbead; Porous Carbon and Synthetic Graphite, which can electrochemically insert and extract lithium reversibly, was investigated in the appointed electrolyte.

在指定组成的有机电解液中，选择三类可电化学嵌脱锂的碳材料：中间相碳微球、多孔碳和人造石墨，研究其表面形成的固体电解质中间相膜的电化学性能。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。