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121.
祝钱莉  唐强  李颖  尹述凡 《有机化学》2006,26(9):1264-1267
以豆腐果苷为原料, 通过Mannich反应与取代苯胺和脂肪酮共合成了七个豆腐果苷衍生物, 均未见文献报道. 其结构经1H NMR, IR, MS和HRMS确认, 并进行了药理活性筛选. 结果表明, 部分化合物均具有良好的镇静活性. 其中, 化合物2a (200 mg/kg), 2b (200 or 100 mg/kg)和2e (200 mg/kg)与豆腐果苷相比较, 具有更强的疗效.  相似文献   
122.
在氩气氛中,合成了SrMgF4:xEu,yTb复合组化物磷光体.该体系中Eu3 和Eu2 共存.随共掺入Tb浓度的增加,Eu3 的荧光发射强度降低,Eu2 的发光增强;并且Eu2 的ESR信号增强.认为Eu3 和Tb3 之间存在电荷迁移.即Eu3 +Tb3 →Eu2 +Tb4 .通过半定量手段研究了这一电荷迁移反应的平衡常数  相似文献   
123.
The effects of three uncoupled metabolic systems (conventional activated sludge process with the addition of 3,3′,4′,5-tetrachlorosalicylanilide [TCS], oxic-settling-anaerobic [OSA] process modified by insertion of a sludge-holding tank in the sludge return line, and TCS and OSA combined process) on reducing excess sludge production were studied. Compared with the control conventional activated sludge process, the most effective system was the combined process, which could reduce excess sludge production by 46.90%. The 180-d operation results confirmed that TCS is an effective chemical uncoupler in reducing the sludge yield but that it had an adverse effect on substrate removal capability, effluent nitrogen concentration, and sludge settleability. The OSA process decreased excess sludge production by only 26% but had less adverse effect on effluent quality and could improve sludge settleability. The effluent total phosphorous concentration of the three systems was slightly lower than of the control unit. Microbial populations were monitored by both microscopic and molecular biologic analysis method (polymerase chain reaction [PCR]-denaturing gradient gel electrophoresis [DGGE]). The presence of TCS caused metazoans to disappear and decreased the number and activity of protozoa. PCR amplification of 16S rRNA and sequent DGGE analysis found a shift in the diversity of the predominant species. The results imply that OSA combined with the chemical uncoupler process may effectively reduce excess sludge yield and not affect process performance significantly.  相似文献   
124.
Zein films plasticized with oleic acid were formed by solution casting, by the stretching of moldable resins, and by blown film extrusion. The effects of the forming process on film structure were investigated by X-ray diffraction. Wide-angle X-ray scattering (WAXS) patterns showed d-spacings at 4.5 and 10 A, which were attributed to the zein alpha-helix backbone and inter-helix packing, respectively. The 4.5 A d-spacing remained stable under processing while the 10 A d-spacing varied with processing treatment. Small-angle X-ray scattering (SAXS) detected a long-range periodicity for the formed films but not for unprocessed zein, which suggests that the forming process-promoted film structure development is possibly aided by oleic acid. The SAXS d-spacing varied among the samples (130-238 A) according to zein origin and film-forming method. X-ray scattering data suggest that the zein molecular structure resists processing but the zein supramolecular arrangements in the formed films are dependent on processing methods. Structural model for a zein molecular aggregate (based on Matsushima et al.10). Rectangular prisms of individual zein molecules are hexagonally aligned parallel to each other.  相似文献   
125.
The recent progress of wide bandgap (WBG) donor polymers for non-fullerene polymer solar cells (NF-PSCs) were reviewed in detail, which was classified by D-type and D-A type molecular backbones to discuss the related structure-property correlations and put forward an outlook for future innovations.  相似文献   
126.
研究了新显色剂5-(对羧基苯偶氮)-8-羟基喹啉(p-CPHQ)与U(Ⅵ)的显色反应条件,在阳离子表面活性剂CTMAB存在下,pH 4.0~6.0缓冲介质中,形成稳定的红色络合物,最大吸收波长为470nm,ε=4.39×10~4,含U(Ⅵ)量在0~55μg/25ml范围内符合比耳定律,结合TBP萃淋树脂分离富集,并以CyDTA、KF联合掩蔽,方法适用于岩石矿物中痕量铀的测定。  相似文献   
127.
Silver halide (AgX) microcrystal was used as template to synthesize hollow polyelectrolyte capsules. These hollow capsules were characterized by laser light scattering (LLS) used to measure the size of the capsules in solution. The ratio of hydrodynamic radius (Rh) from dynamic LLS to the radius of gyration (Rg) from static LLS is almost unity, revealing that the entities are hollow in solution. The results suggest that the LLS method can be regarded as a good complement to the confocal laser scanning microscopy (CLSM) method for the characterization of small hollow capsules, and it possesses the advantage of not needing fluorescence labeling.  相似文献   
128.
A benzophenone derivative photoinitiator, HBP-TDI-HQ-TDI-HBP (HTCTH), was synthesized based on 4-hydroxy benzophenone (HBP), toluene-2,4-diisocyanate (TDI) and hydroquinone (HQ). HTCTH was a more effective photoinitiator which had longer wavelength absorption in the UV-vis absorption spectra than the low molecular counterpart benzophenone (BP). It showed that both rate of polymerization (Rp) and final conversion (P) increased with increase of amine and HTCTH concentration in photopolymerization.  相似文献   
129.
A new nickel(Ⅱ)-dicyanamide compound, [Ni(dca)2(en)]n (1) (dca=dicyanamide anion, [N(CN)2]-); en=ethylene diamine), has been synthesized and its structure has been determined by single crystal X-ray diffraction analysis. The crystal is monoclinic, space group P21/n with unit cell dimensions: a=0.694 3(1) nm, b=1.041 5(2) nm, c=1.4132(2) nm, and β=90.381°, Z=4, V=1.011 0(3) nm3. In this compound, the adjacent nickel atoms are connected by dca all in μ1,5-bridging mode to form ladder-like units, which are linked with double dca bridges to generate a regular infinite stair-like structure. Temperature-dependent magnetic susceptibility was also characterized for this compound. CCDC: 208276.  相似文献   
130.
新型卤代羟基三苯醚的合成与抑菌活性研究   总被引:2,自引:0,他引:2  
设计合成了对(间、邻)苯二酚二(4-氯-2-羟基苯基)醚(4a~4c)及对(间、邻)苯二酚二(4-氯-5-溴-2-羟基苯基)醚(5a~5c)共6个卤代羟基三苯醚类化合物,其结构均经1H NMR,IR,MS和元素分析证实,并且对其抑菌活性进行了初步测试.结果表明:此类化合物大多在低浓度下对大肠杆菌、金黄色葡萄球菌、白色念珠菌、白色葡萄球菌、变形杆菌、卡他双球菌、青枯假单胞菌等具有良好的抗菌活性.  相似文献   
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