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11.
三氟醋酸钆的晶体结构   总被引:2,自引:0,他引:2  
测定了[Gd(CFCOO)_3·3H_2O]_2的晶体结构属单斜晶系,空间群为P2_1/c.Z=2.晶胞参数a=9.192(3),b=18.890(1),c=9.785(3);β=113.84(2)°.[Eu_(0.1)Gd_(0.9)(CF_3COO))3·3H_2O]_2的光谱构分析表明稀土离子周围的局部对称性可能是C_2(C_s)和C_2h。  相似文献   
12.
双胍辛醋酸盐杀菌剂及其两种中间体的合成与生物活性   总被引:5,自引:0,他引:5  
O-methylisourea acetate was synthesized by two procedures from the main raw materials including carbamide, dimethyl sulfate, acetic acid and concentrated sulfuric acid. Its content reaches 98 % and the total yield attains to 70%. 1, 17-Diamino-9-azaheptadecane was first synthesized by two procedures using sebcic acid, 1,8-octanediamine, sodium azide and concentrated sulfuric acid as the main raw materials. Its content reaches 98% and the total yield is 65%. The structure of both were confirmed by FT-IR, ^1H NMR and their available analysis method was established. Fungicide bis-(8-guanidino-octyl )amine acetate was synthesized from these two intermediates and its structure was confirmed by FT-IR and ^1HNMR. Fungicidal activity test showed that it is a kind of broad-spectrum fungicide with notably effect.  相似文献   
13.
利用不同溶剂合成并测定了希土三氯醋酸盐与α,α'-联吡啶(bipy)不同比例的配合物(Ⅰ)La:bipy=1:1,[La(CCl3COO)3(bipy)·H2O]2和(Ⅱ)Tb:bipy=1:2,Tb(CCl3COO)3(bipy)2·H2O,结构测定表明配合物(Ⅰ)与(Ⅱ)均为三斜晶系,中心离子La(或Tb)具有配位数为8的畸变四方反棱柱多面体;但是配合物(Ⅰ)形成具有对称中心的二聚体.  相似文献   
14.
Thirteen new ethyl 2-(N-substituted-arylsulfonamido)-2-oxoacetates(3a-3m), based on the structure of Ketol-acid reductoisomerase(KARI) inhibitor IpOHA, were designed and synthesized. Their structures were established on the basis of ^1H NMR, IR, MS, and elemental analyses. The bioassay result reveals that the structural changes from hydroxyl group on the N atom of IpOHA to arylsulfonyl groups does not enhance the inhibitory activity of the compounds to KARI in vitro. Compounds 3c, 3h, 3k, and 3m are more effective than IpOHA against the monocotyledonous bamygrass at 100 ug/mL in herbicidal tests.  相似文献   
15.
The viability and biological activity of Absidia coerulea in compressed or supercritical CO2 and C2H4 were studied. The specific activity ofAbsidia coerulea in 7.5MPa CO2 and C2H4 at 306K can reach to 23% and 75% respectively, leading to the feasibility of using supercritical C2H4 as an alternative to the organic solvent in the hydroxylation of Reichsterin‘s substance acetate.  相似文献   
16.
蔡清海  王虹  金超  路嫔  吴锋  单永奎 《中国化学》2005,23(8):990-992
Two novel ionic liquids, N,N'-disalicylideneethylenediaminium acetate and N,N'-disalicylideneethylenediaminium trifluoroacetate, were prepared and characterized by IR, ^1H NMR, DTA-TG and elemental analysis. The experimental results indicate that the new ionic liquids possess lower melting point and higher electrical conductivity. It is noteworthy that the ionic liquids reported herein are the first member of the ionic liquid family with the Schiff base functional group in the cation.  相似文献   
17.
王月红林海  林华宽 《中国化学》2007,25(10):1430-1433
A colorimetric anion receptor was synthesized by a simple method where the phenylhydrazone moiety was need as binding sites. The anion recognition via hydrogen-bonding interactions can be easily monitored by anion complexation induced changes in UV-vis absorption spectra. Moreover, the hydrogen bond formation between the phenylhydrazone N-H and acetate or fluoride anion was described on the basis of ^1H NMR experiments.  相似文献   
18.
制备了离子液体1-甲基咪唑醋酸盐([Mim]Ac),1,3-二甲基咪唑醋酸盐([Mmim]Ac)和1-乙基-3-甲基咪唑醋酸盐([Emim]Ac),分别测定了它们在293.15-338.14 K间的密度、电导率和绝对粘度,计算了相应的摩尔电导率和运动粘度.用最小二乘法分别拟合建立了密度、电导率、摩尔电导率、绝对粘度和运动粘度与温度的函数关系.讨论了咪唑环3位氮原子上烷基链长对以上咪唑醋酸盐五种物理化学性质的影响.在293.15 K测定了[Mim]Ac{或[Mmim]Ac,[Emim]Ac}(1)-H2O(或EtOH)(2)二元溶液在全浓度范围内的电导导率,计算了对应的咪唑醋酸盐的摩尔电导率.发现无论是水溶液还是乙醇溶液,溶液的电导率和咪唑醋酸盐的摩尔电导率都随着浓度的增加先增大而后减小.同一浓度下,咪唑环3位氮原子上烷基链长增加,相应的溶液电导率和摩尔电导率下降.且水溶液的电导率和摩尔电导率远大于乙醇溶液的.  相似文献   
19.
pacc:7855K Materialsexhibitingthermallyinducedther mothickeningorgellingpropertiesinaqueousso lutions,i.e.presentingasubstantialviscosityin creaseuponheatingareratherexceptional,as mostfluidsarecharacterizedbythewell-known Arrheniusthermothinningbehavi…  相似文献   
20.
张静筠  张思远 《发光学报》1989,10(3):237-242
本文合成了系列稀土三氟醋酸盐晶体[Re(CF3COO)3·3H2O](Re=Eu,Gd,Tb,Dy)和[TbxY1-x(CF3COO)3·3H2O]2(x=0.05,0.10,0.15,0.20,0.25mol),测定其晶体结构属单斜晶系,空间群为P21/c;较详细地讨论了Eu3+,Gd3+,Tb3+,Dy3+在这些化学计量化合物中的光谱特性,以及在[TbxY1-x(CF5COO)3·3H2O]中Tb3+的发光强度随其浓度的变化规律。  相似文献   
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