大环

• New developments of polycarboxylic acid derivative catalysts , ion exchange resin catalysts , macrocyclic chelating compound catalysts , quaternary phosphonium salt catalysts , heterogeneous hydrotalcite - type catalysts and other catalysts which to be used in ethylene oxide catalytic hydration , and the catalysts of synthesis method of ethylene glycol via preparation and reaction of ethylene carbonate are expounded
  阐述了用于环氧乙烷催化水合反应中的多羧酸衍生物催化体系、离子交换树脂催化体系、大环螯合物催化体系、季?盐催化体系、多相水滑石型催化体系及其他催化体系近年来的研究进展；同时阐述了用于碳酸亚乙酯法合成乙二醇反应中的催化体系的新进展。
• The high island water system had a transport network that included numerous underground tunnels , in total 25 miles long , with diameters of 10 to 13 ft . the main water tunnel was 74 , 000 ft . long ( 14 miles ) , beginning at pak tam chung , near high island , and going through the sai kung peninsula and tai wan to reach the sha tin treatment works
  万宜水库的输水网络包括了多条直径10至13尺、共长约25哩的输水隧道，隧道主线长74 , 000尺（ 14哩） ，由万宜水库北潭涌起，横越整个西贡半岛，经西贡大环至沙田滤水厂。
• Content : avermectins are a class of drugs which have been found wide usage against a board spectrum of nematodes and arthropods , many of which are important endoparasites and ectoparasites of animals . avermectin bi is a common agriculture pesticide produced by the actinomycete streptomyces avermitilis and registered for worldwide use
  正文：阿维菌素类药物( avermectins ， avms )属大环内酯类抗生素，由于其优异的驱虫活性和较高的安全性，被视为目前最为优良、应用最广泛的兽用驱虫药。
• Testing parameters include aminoglycosides , - lactams , macrolides , polypeptides , quinolones , sulfonamides , tetracyclines , lincomycin , spectinomycin , trimethoprim and chloramphenicol . in august 2004 , the hong kong accreditation services made a re - assessment visit to the man kam to food laboratory . the laboratory succeeded in re - affirming its accreditation status and extending its accreditation scope to cover the testing of vegetables and milk for more pesticide residues and veterinary drug residues respectively , under the hong kong laboratory accreditation scheme hoklas
  Ii测试未经加工的奶类所含残馀兽药，包括是否含有氨基糖类类药物-内胺类药物大环内脂类药物多类药物诺酮类药物磺胺类药物四环素类药物林可霉素大观霉素甲氧苄氨嘧啶和氯霉素。
• Cyclic pressing is a new kind of densification processing , which is introduced to densify as - deposited ring of al - 20 % si / sicp . this paper includes the densification result and rule of this technics . the research shows that this technics can be successfully used to densify spray - forming porous material and can be availably adopted to improve mechanical performance and microstructure . this technics is characterized by simple equipment 、 small expense and flexible process , and these characters will make it come true to producing spray - deposited rings less costly
  本文采用一种新型致密化工艺?楔压工艺?对喷射沉积al - 20 % si / sicp大环进行了致密化加工,采用密度硬度分布、抗拉强度变化和检测显微组织变化的实验研究方法对其致密化效果及该工艺规律进行了研究,通过研究表明了楔压工艺可以成功地用来致密化喷射沉积多孔材料,该工艺有效地提高了喷射沉积大环件的致密度和抗拉强度并改善了组织。
• A great deal of research is being devoted to the understanding of systems , biomimetic and otherwise , that self - assemble into organized structures . liquid crystals represent one of the best known classes of self - organizing materials , exhibiting properties that range from surfactants that can form micelles , monolayers , and membranes , to the rodlike molecules used in liquid crystal displays , to the recently discovered disc - like liquid crystals
  卟啉液晶分子是一种共轭大环化合物，其周边有十二个活性部位可与不同的柔性侧链相连接，且分子的长径比与直径厚度比等均可以调整，因此，可以通过分子设计在卟啉的周边引入柔性侧链合成出新型具有期望性质的卟啉液晶材料。
• Ftir and xps proved that ptcda and tcpc were attached on the surface of silicon by covalent ; afm and uv - vis showed ptcda and tcpc arranged orderly on surface of silicon ; through raman spectrum , we found that macrocycle molecules stand on surface of silicon , while macrocycle molecules in film by vacuum deposition parallel to silicon surface
  红外光谱和光电子能谱证明了?和酞菁成功的化学键合到单晶硅表面， afm和uv - vis吸收光谱表明了?和酞菁单层膜在硅基上呈有序排列。拉曼光谱的研究发现?酐分子大环以一定的角度立于硅基表面，而不是平行于基体表面，与蒸镀手段得到的?酐膜的堆积形态完全不同。