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991.
The complexing process proceeding in the NiII–thiocarbohydrazide (H2N–H–NC(=S)–NH–NH2)–propanone triple system in EtOH solution and nickel(II)hexacyanoferrate(II) gelatin-immobilized matrix has been studied. It has been found that in the first case, template synthesis leading, as a minimum, to formation of three coordination compounds of NiII with (N,N,S,S)-donor tetradentate ligands having NiL1, NiL2 and NiL3compositions where L1 is 4,6,6-trimethyl-2,3,7,8-tetraazanonen-3-di(thiohydrazide)-1,9, L2 is 4,6,6,12-tetrametyl-1,9-dithio-2,3,7,8,10,11-hexaazatridekadien-3,11-hydrazide-1 and L3 is 2,8,10,10,16-pentamethyl-5,13-dithio-3,4,6,7,11,12,14,15-octaazaheptadekatrien-2,7,15 is observed, whereas in the gelatin-immobilized matrix, a complexing process in the system considered does not occur.  相似文献   
992.
描述了以镍单核配合物NiCp2和簇合物Ni3Cp3N-t-C4H9为前体的SiO2载镍催化剂的制备,通过元素分析、TRR、TPDE、XPS,CO吸附和苯加氢反应对以镍配合物和簇合物为前体制备的催化剂的性能及其制备过程了研究和表征。结果表明,镍与合物和簇合物在担载过程中同载体SiO2表面发生了相互作用,其化学组成发生了变化,在苯加氢反应中,此催化剂的活性比以Ni(NO3)2为前体制备的催化剂高得多,  相似文献   
993.
Alternate adsorption of positively charged colloid-Au nanoparticles (nano-Au⊕) and negatively charged hemoglobin (Hb) on L-cysteine (L-cys) modified gold electrode resulted in the assembly of {Hb/nano-Au⊕}n layer-by-layer films/L-cys modified gold electrode. The nano-Au⊕ was characterized by transmission electron micrograph (TEM) and microelectrophoresis. The modified electrode interface morphology was characterized by electrochemical impedance spectroscopy (EIS), atomic force mi- croscopy (AFM), cyclic voltammograms (CV) and chronoamperometry. Direct electron transfer between hemoglobin and gold electrodes was studied, and the apparent Michaelis-Menten constant ( km app) of the modified electrode was evaluated to be 0.10 mmol·L?1. Moreover, the higher activity of proteins in the nano-Au⊕ films could be retained compared with the electropolymerization membrane, since the pro- teins in nano-Au⊕ films retained their near-native structure. Direct electron transfer between hemoglo- bin and electrode and electrochemically catalyzed reduction of hydrogen peroxide on a modified elec- trode was studied, and the linear range was from 2.1×10-8 to 1.2 ×10?3 mol·L-1 (r = 0.994) with a detection limit of 1.1×10-8 mol·L-1 H2O2.  相似文献   
994.
This study investigated the flavonoid constituents of a traditional Chinese medical plant Ziziphora clinopodioides Lam. by using ultra-performance liquid chromatography coupled with quadruple time-of-flight mass spectrometry and screened the active components in regulating autophagy.Normal rat kidney (NRK) cells transfected with green fluorescent protein- microtubule-associated protein 1 light Chain 3(GFP-LC3) were treated with Z. clinopodioides flavonoids and its chemical compositions. After 4 h of treatment, the auto-phagy spot aggregation in NRK cells was photographed and observed by laser scanning confocal microscopy. The following 10 flavonoid components of Z. clinopodioides were identified: baicalein(1), quercetin(2), hyperoside(3), quercetin3-O-β-d-glucopyranoside(4), apigenin(5), kaempferol(6), chrysin(7), diosimin(8), linarin(9) and rutin(10). Among these flavonoids, chrysin, apigenin and quercetin were identified as the active principles in activating autophagy. This research may provide a reference for further developing and utilizing Z. clinopodioides.  相似文献   
995.
 A GLP study can be performed at more than one site. This is called a multi-site study. Although, the study is performed at different sites, it is still one study and must completely comply with the GLP principles. The fact that different activities are conducted at different sites implies that the planning, the organization and the communication are crucial for the success of the study. This means that all the staff involved should know their responsibilities and should have the knowledge and skills to realize all the phases of the study according to the GLP principles. To achieve a well managed multi-site study, several strategies for setting up such a study can be followed. This paper focuses on the responsibilities, communication, and collaboration of the personnel, which are involved in a multi-site study. Several case studies are highlighted, and we concluded that the basic communication triangle in a single-site GLP study between test facility management, study director, and the quality assurance unit should be extended to the communication among test facility and test site management, study director, principle investigator(s), and the quality assurance units at the test sites. Introduction Received: 14 August 2002 Accepted: 26 November 2002  相似文献   
996.
The bridged tri-imidazoliums 3.3X^--5.3X^-(X^-=PF6^-,Br^-,I^-)and bis-imidazoliums 6.2PF6^- were synthesized by N-quaternization of imidazole derivative 1 in acetonitrile under reflux.UV spectroscopic titration experiments showed that the halide salts and hexafluorophosphate salts of these imidazoliums exhibited good recognition toward anions in water and in acetonitrile,respectively.  相似文献   
997.
In search for a cheaper anode catalyst for the oxidation of ethanol for development of direct alcohol fuel cells, Pd has been considered here as an interesting substitute for Pt in Pt Ru binary electrodeposite. The binary catalyst when co-deposited on nickel support has been found to increase the current density and decrease the anodic overvoltage significantly with respect to pure Pt, Pd and Ni. Its electrocatalytic capability is also comparable with that of the Pt-Ru binary electrocatalyst on Ni-support, when studied in 1 M EtOH containing 1 M NaOH solution. The effect of loading of Pd Ru electrocatalyst on Ni support has also been tested. The electrocatalytic activity of the electrodes for oxidation of ethanol has been explained by studies of cyclic voltammetry, chronopotentiometry, steady-state polarization, and conjugated scanning electron microscopy–energy dispersion X-ray spectroscopy. It has been found that electrode containing the higher amount of deposit are less affected by carbonaceous poisons.  相似文献   
998.
The microwave-mediated reaction of 4-aryl-4-oxobutanoic acids with benzylamines furnished 1-arylmethyl-3-[(E)-1-arylmethylidene]-5-phenyl-2,3-dihydro-1H-pyrrolones. This result is in contract to the earlier report on this reaction conducted under neat conditions. Structures for the products were assigned on the basis of spectral data and confirmed by independent synthesis. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 368–373, March, 2007.  相似文献   
999.
人血清与头发中铜,锌,铁,钙,镁,锰含量的相关分析   总被引:3,自引:0,他引:3  
平行测定了54例(男31例,女23例)成人血清和头发中铜,锌,铁,钙,镁和锰的含量,相关分析结果表明,血清与头发中6种元素的不相关两类样品比较,血清测定方法简便,误差小,但在检测人体内元素含量水平时,头发的测量结果比血清更灵敏。  相似文献   
1000.
The volatile chemical constituents of Artemisia capillaries (an important traditional Chinese medicine) were determined by gas chromatography-mass spectrometry (GC-MS) and sub-window factor analysis (SFA). Seventy-five components were separated and 43 of them were qualitatively and quantitatively determined, which represented about 89.03% of the total content. This profile was then used to identify and assess the consistency of the herb by using an orthogonal projection method. Four different sources of A. capillaries were analyzed and compared with each other. Among the components determined, there were 51 components coexisting in all samples although the relative peak areas of a few showed variations. It is the first time to apply orthogonal projection method to the comparison of different samples, and it reduces the burden of qualitative analysis as well as the subjectivity. The results showed a fair consistency in their GC-MS fingerprint. A. capillaris was distinguished from Artemisia sacrorum L., a possible substitute in traditional Chinese medicine by comparing the fingerprints with each other.  相似文献   
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