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双语推荐：环化

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环糊精由于其优异的结构特征和物理化学性质,已成为构筑各种功能材料的优良结构单元.本综述以β-环糊精的共价固载为主,详细综述了目前β-环糊精的固载及其应用最新研究进展,主要包括固载化β-环糊精在环境污染物吸附、药物分子的负载和缓释、分析检测、手性分离、催化、织物整理和表面功能化等领域的应用.上述各部分,根据载体或应用方式的不同,系统介绍了β-环糊精的固载及固载化β-环糊精的性能.指出固载化β-环糊精在催化和表面功能化领域的应用虽然目前还处于起步阶段,却极具研究价值,对固载化β-环糊精进一步的功能化是今后基于β-环糊精构筑超分子仿生催化体系的主要研究方向.
Cyclodextrin has become an excellent unit in the construction of various functional materials due to its unique structural characteristics and physical-chemical properties. Herein, the immobilization ofβ-cyclodextrin and their application at present have been reviewed in detail focusing on the covalent immobilization, especially including the application of the immobilized β-cyclodextrin in the environmental pollutants adsorption, drug loading and releasing, analysis and detection, chiral separation, catalysis, textile finishing, surface functionalization and so on. In the application mentioned above, the im-mobilization ofβ-cyclodextrin and their performance were presented systematically according to the supporter or application modes. It is pointed out that the applications of the immobilizedβ-cyclodextrin in catalysis and surface functionalization are just in their infancy, but having promising prospect. The further functionalization of the immobilizedβ-cyclodextrin w

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出现壅塞空化现象时,壅塞管内流场会发生剧烈变化。利用计算流体力学软件Fluent,采用标准模型k-和多相流空化模型,在不同入口速度和背压条件下对具有壅塞环的空化器进行数值模拟,分析空化器壅塞环在不同位置时,空化区域内静压力和空隙率的分布情况。试验结果表明：壅塞环可以增加壅塞截面下游的恢复压力,且壅塞环离环形喷嘴出口越远,作用越明显;壅塞环可以增大产生壅塞空化的最佳背压范围,且壅塞环离环形喷嘴越近,产生壅塞空化流动的背压范围越大。
Cavitating flow in choking pipe changes violently under chocking cavitation. Using the computational fluid dynamics software of Fluent, the standard k- model and multiphase flow cavitation model, mode numerical simulation on the cavitator with choking ring under different inlet velocity and back pressure conditions, analyzed the distributions of static pressure and void ratio in cavitation area when the choking ring at different position. The results show that choking ring can prompt the back pressure of the down stream of choking cross, and the farther choking ring from the annular nozzle exit is, the more obvious the effect is. The choking ring can increase the range of optimum back-pressure generating choking cavitation, and the closer choke ring from the annular nozzle is, the pressure range of cavitating flow bigger is.

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利用实验的方法研究了涂层对绕水翼空化流动特性的影响。分别针对喷涂环氧涂层和氟碳涂层的 Clark-Y 型水翼，采用高速摄像装置观察了不同空化阶段的空化流动形态。研究结果表明：（1）在初生空化阶段，当σ=1.82时，沿环氧涂层水翼表面展向排列着初生空泡，而氟碳涂层水翼还处于无空化状态，说明相对于环氧涂层，氟碳涂层对空化现象的产生有一定的抑制作用，氟碳涂层水翼初生空化数为1.50；（2）在片状附着型阶段，当σ小于1.63时，绕环氧涂层水翼的空化先于氟碳涂层水翼发展至片状空化，绕水翼空化流动产生大量分散空泡，沿水翼表面向后运动过程中逐渐长大，在高压区溃灭后形成小空泡并以马蹄涡形式继续运动。同一空化数下，绕环氧涂层水翼空化流动的空泡长度大于氟碳涂层水翼。但随空化数降低，两者空泡长度逐渐接近，说明环氧涂层在片状空化阶段对空化的抑制作用逐渐增强；（3）σ=0.87时空化发展至云状空化阶段，空化流动伴随周期性的云状空泡的脱落，绕环氧涂层水翼的空化流动周期及无量纲空化面积均小于氟碳涂层水翼，说明涂层对空化的非定常变化也有一定的抑制作用，且环氧涂层强于氟碳涂层。
Influence of surface coatings on cavitating flow around hydrofoils is studied experimentally. Hy-drofoils are painted with epoxy coating and fluorocarbon coating, respectively. High speed visualization sys-tem is used to observe the cavitation flow patterns in different stage. The results show three main phenome-na. Firstly, in stage of incipient cavitation, obvious cavities occur in form of bubbles dispersal along spanwise direction on the suction side of hydrofoil coated by epoxy when σ=1.82, while no cavitation occurs around fluorocarbon hydrofoil. So the fluorocarbon coating is helpful in restrict on the occurrence of cavitation. The incipient cavitation number for fluorocarbon hydrofoil is 1.50. Secondly, in stage of attached sheet cavita-tion, cavitating flow around fluorocarbon hydrofoil develops into sheet cavitation when σ small than 1.63, which is earlier than that of epoxy foil. The cavitating flow consists of clusters of dispersive bubbles and cavi-ties become l

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文章综述了通过烯烃的氮杂环丙化和 C-H 键的酰胺化制得有机胺类化合物的研究进展,包括烯烃的氮杂环丙化反应、苄基 C-H 键的胺化、醛 C-H 键的酰胺化、醚的胺化.
In the paper, the organic amine compounds is prepared through aziridination of alkenes and amination of hydrocarbons. It includes aziridination of alkenes, amination of benzylic C-H bond, amidation of aldehydes via C-H activation as well as amidation of ethers.

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根据环糊精衍生物分子结构与形态的不同，分类综述了环糊精衍生物（以β-环糊精衍生物为主）的形态及其构筑策略研究进展，包括单取代环糊精衍生物、双取代环糊精衍生物、多取代环糊精衍生物、二聚体环糊精衍生物、多聚体环糊精衍生物和环糊精聚合物（包括固载化环糊精）。指出环糊精衍生物的构筑是基于环糊精构筑各种功能材料的基础与关键，是环糊精母体应用的进一步拓展。基于环糊精构筑各种超分子仿酶，不仅可以充分发挥环糊精结构上的先天优势，也可以实现有机合成反应从有机相到水相的顺利过渡，并提高反应的选择性，对有机合成化学的“绿色化”具有重要的意义，对其他功能材料的构筑也具有重要的参考价值和指导意义。
The molecular morphology of cyclodextrin derivatives and their construction strategy (mainly theβ-cyclodextrin derivatives) were reviewed comprehensively according to the difference in molecular structure and morphology,including mono-substituted cyclodextrin derivatives, bis-substituted cyclodextrin derivatives,multi-substituted cyclodextrin derivatives,dimer cyclodextrin derivatives,multimer cyclodextrin derivatives and cyclodextrin polymers (including immobilized cyclodextrins). It was pointed out that the construction of cyclodextrin derivatives was the foundation and key step in the building of various functional materials,could be further expanded in the application of parent cyclodextrin. To construct various supramolecular artificial enzymes based on cyclodextrin,not only can make full use of the inherent advantages of cyclodextrin structure,but also can realize the smooth transition of organic synthesis reactions from organic phase to aqueous phase with enhanced sel

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研究了Ce3+对大白鼠肝脏质膜腺苷酸环化酶的影响及Ce3+对培养原代肝细胞内cAMP含量的影响.结果表明,低浓度的Ce3+抑制质膜腺苷酸环化酶的活性,高浓度的Ce3+能使质膜腺苷酸环化酶的活性恢复;在培养基中加入Ce3+能使肝细胞内cAMP含量增加,茶碱能强化Ce3+的作用,表明Ce3+能激活腺苷酸环化酶.结果提示Ce3+对环腺苷酸信号系统的影响可能是稀土元素对生物的作用机制之一.
s In this paper, the effect of cerium(Ⅲ) on adenylate cyclase in rat liver was studied. The results showed that cerium(Ⅲ) could inhibit the AC activity of rat liver plasma membrane in low dose and recover it in high dose. Cerium(Ⅲ) also could enhance the concentration of cAMP in primary hepatocyte by adding theophylline in medium. These results suggested that the cerium(Ⅲ) might affect the cAMP signal system. The influence of cerium(Ⅲ) on cAMP signal system might be one of the mechanisms by which rare earth elements affect living things.

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本文中研究聚合物对煤沥青中多环芳烃的脱除效果,着重从聚合物、催化剂添加量,反应时间和温度等因素对多环芳烃脱除率的影响,同时研究采用复合改性剂对煤沥青中多环芳烃的脱除效果.通过红外光谱分析,初步了解聚乙二醇与多环芳烃反应属于O-烷基化反应,三聚甲醛与多环芳烃反应属于C-烷基化反应.
This paper studied the removal effect of polymer on polycyclic aromatic hydrocarbons in coal tar pitch ,focusing from polymer ,catalyst amount ,reaction time and reaction temperature on effect of polycyclic aromatic hydrocarbon removal rate , and discussed the effect of removal of polycyclic aromatic hydrocarbons in coal tar pitch with the mixture of polyethylene glycol and s-Trioxane .Through the analysis of infrared spectrum ,speculated that the polyethylene glycol and PAHs reaction belonged to O-alkylation reaction , s-Trioxane and PAHs reaction belonged to C-alkylation reaction .

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以油酸和二乙烯三胺为主要原料,二甲苯为携水剂,合成了油酸咪唑啉中间体。通过正交实验,考察了原料配比、酰胺化时间、酰胺化温度以及环化温度对合成产物缓蚀性能的影响。确定最佳的反应合成条件为:油酸与二乙烯三胺的摩尔比为1∶1.2,酰胺化温度为160℃,酰胺化时间为3 h,环化温度为220℃,环化时间为4 h。合成的油酸咪唑啉缓蚀率达到86.64%。
Oleic acid and diethylene triamine as the main raw material , xylene as carrying agent , oleic imidazoline intermediates was synthesized.By orthogonal experiment , the effects of material ratio, amidation time, temperature and cyclic amide temperature on corrosion properties of the synthesized product were investigated .The optimal reaction conditions were that the molar ratio of oleic acid and diethylene triamine was 1:1.2, amidation temperature was 160℃, amidation time was 3 h, cyclization temperature was 220 ℃, and cyclization time was 4 h.Inhibition rate of the imidazoline oleic acid synthesis reached 86.64%.

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采用直接共聚法合成表面含有乙烯基的具有立方相Ia3d结构的介孔硅分子筛（V-ClMS），然后对乙烯基团进行环氧化制备得到表面环氧基功能化的介孔硅分子筛（E-CIMS），采用X射线衍射、N2吸附-脱附、透射电镜、热重分析和13C固体核磁共振对制备的介孔硅分子筛进行了表征。结果表明，表面含有乙烯基的V-ClMS介孔硅分子筛能被一步成功合成，并易于发生环氧化而获得表面环氧基功能化的E-CIMS介孔硅分子筛。将E-CIMS介孔硅分子筛作为载体用于固定化青霉素G酰化酶（PGA），研究了表面环氧基团对固定化PGA初活性和操作稳定性的影响。结果表明，随着表面环氧基团数量的增加，介孔硅分子筛孔径减小，表面疏水性增加，导致载酶量和初活性减小。但介孔硅分子筛表面适量的环氧基团能增强E-CIMS介孔硅分子筛与PGA之间的相互作用，从而提高固定化PGA的操作稳定性。
Epoxy functionalized cubic Ia3d mesoporous silica (CIMS) was successfully synthesized by epox-idizing vinyl groups prepared on the CIMS by a co-condensation method. The synthesized material was characterized by X-ray diffraction, nitrogen sorption, transmission electron microscopy, ther-mogravimetric analysis, and solid state 13C NMR. The vinyl groups were found to be easily epox-idized to yield epoxy functionalized CIMS. The epoxy functionalized CIMS was used as a support for the immobilization of penicillin G acylase (PGA), and the effects of the epoxy group on the initial activity and the operational stability of the immobilized PGA were studied. The results showed that the enzyme loading and initial activity of the immobilized PGA decreased with increasing amounts of epoxy groups. These observations were due to a decrease in the pore size of the mesoporous silica as well as an increase in the hydrophobicity of the silica surface. However, an appropriate amount of epoxy gr

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以 Ni-Mo-W 复合氧化物为活性组分前躯物，采用干混法、湿混法和共胶法分别制得3种不同的非负载型加氢催化剂，以四氢萘为模型化合物对其选择性开环脱芳烃性能进行评价。结果表明：四氢萘的加氢开环过程是由加氢脱氢、异构化、开环作用、脱烷基及烷基转移等反应组成的复杂反应；共胶法催化剂具有较高的加氢活性，四氢萘转化率较高，并且其异构化和开环能力显著高于其它两种催化剂；湿混法催化剂具有较高的加氢选择性，四氢萘转化率较高，但其异构化和开环选择性较低；干混法催化剂作用下的四氢萘转化率、异构化选择性、开环选择性及加氢选择性均较低。采用共胶法和湿混法催化剂时四氢萘加氢开环主要遵循单分子机理，生成重组分的量较少。
Tetralin hydroconversion process is a complex reaction consisting of the hydrogenation, dehydrogenation, isomerization, ring-opening, alkyl and transalkylation. Unsupported Ni-Mo-W hydroupgrading catalysts were prepared by three different preparation methods (dry mixing,wet mix-ing,co-gelling),and tetralin was selected as a model compound to evaluate the hydrogenation and selec-tive ring-opening performance of the catalysts. The results show that the catalyst prepared by co-gelling shows higher hydrogenation conversion of tetralin as well as higher selective ring opening and isomeriza-tion performance than the other two catalysts. The wet mixing catalyst has a high hydrogenation selec-tivity and tetralin conversion rate,but lower in isomerization and ring-opening selectivity. The tetralin conversion rate,the isomerization selectivity and the hydrogenation selectivity are low for the dry mix-ing catalyst. The single molecule mechanism is mainly followed for tetralin hydrogenation and ri

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