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1.
以简单酸铵盐为原料,采用不同的磷钼锑比,在控制反应温度70~80℃、溶液酸度2.5~3.0N的条件下,进行分步反应的方法,首次合成了以锑原子取代的钼锑磷杂多酸铵。通过元素分析,确定了它们的组成;用pH滴定曲线、电子吸收光谱和X射线等方法研究了它们的性质。  相似文献   

2.
Synthesis and Characterization of ZnO Nanowires   总被引:1,自引:0,他引:1  
Zinc oxide is a wide bandgap (3.37 eV) semiconductor with a hexagonal wurtzite crystal structure. ZnO prepared in nanowire form may be used as a nanosized ultraviolet light-emitting source. In this study, ZnO nanowires were prepared by vapor-phase transport of Zn vapor onto gold-coated silicon substrates in a tube furnace heated to 900 ?C. Gold serves as a catalyst to capture Zn vapor during nanowire growth. Size control of ZnO nanowires has been achieved by varying the gold film thickness…  相似文献   

3.
A new diamine, disodium 4, 4‘-di(4-aminophenoxy)-3, 3‘-disulfonate-1, 1‘-diphenylketone, was prepared from the nucleophilic substitution of disodium 4, 4‘-difluoro-3, Y-disulfonate-1, l‘-diphenylketone and p-aminophenol. Polymerization of this diamine and 4,4‘-diamino-1, 1‘-diphenyl ether with 3, 3‘, 4, 4‘-tetracarboxyl dianhydride-1, 1‘- diphenyl ketone gave ion-exchange copolyimide. The new diamine and its polyimide were characterized with ^1H-NMR and FT-IR.  相似文献   

4.
Preparation and Characterization of Molybdotungstoniobogermanic Acid   总被引:1,自引:0,他引:1  
Recently,thepreparationandpropertiesofheteropolycomplexeshaveincreasinglyattractedattentioninvariousfieldsofchendstIy,especiallyincatalysicapplicationsfortheiruniqueproperties'.Sincel988,thestudiesoffour-baseheteropolycomplexeswiththeKegginstructurehavebeenreported.Asthespecialbifunctionalcatalyticand.-lantisepsispropertyoftheheteropolycomplexescontainingniobium',andsofarthemolybdotungstoniobogermanicheteropolycomplexesinwhichthecentralatomisgermanium,havenotbeenreportedyet,ennea-tungsto-bi-mo…  相似文献   

5.
Porous carrier MgO which was aggregated by nano-particles has been firstly prepared byusing a normal technology route. The MgO was rod-shaped and had large surface area. Thefactors which affect grain size and microstructure of MgO were explored.  相似文献   

6.
A new series of ferrocenesulfonyl benzimidazle has been synthesized and characterized by 1H NMR, FT-IR and elemental analysis. They are expected to have special bio-activity.  相似文献   

7.
Composite microspheres composed of monodispersed poly(St-co-MAA) latices with diameter about 260 nm as core and Ag nanocrystals as shell were prepared by an in situ reduction method. The shell thickness could be controlled in the range of 15--45 nm by this coating process. The structure and the composition of the core-shell microspheres were characterized by transmission electron microscopy (TEM), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TG). The formation of the composite microspheres is explained by the nucleation of silver on the surface of the latices followed by growth of the silver shell.  相似文献   

8.
SynthesisandCharacterizationofChiralLiquidCrystalCMPPCDPTIANYan-qing,ZHAOYing-ying,SUFeng-yuandTANGXin-yi(DepartmentofChemist...  相似文献   

9.
Lithium 2-picolylselenolate/tellurolate is obtained by reacting lithiated 2-picoline with elemental selenium/tellurium which upon aerial oxidation gives 2,2'-dipicolyl diselenide in case of selenium while 1,2-bis(2-pyridyl)ethane in case of tellurium. Condensation of 2-picolylselenolate anion with a variety of electrophiles provides a facile synthesis of 2-picolylalkyl selenides in good to excellent yields. Quenching of lithiated 2-picoline with 2,2'-dipyridyl diselenide gives mixed 2-picolylseleno pyridine in low yield. All the compounds prepared are new and have been characterized by elemental analysis, 1 H NMR, 13 C NMR and mass spectral studies.  相似文献   

10.
Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interracial polycondensation reaction. The products were characterized by means of Fourier transform infrared spectrometry, ^13C NMR spectrometry and ^31p NMR spectrometry. The morphology, the particle size and the particle size distribution, and the thermal properties were also evaluated. The prepared microcapsules exhibit clear and smooth surfaces and have a mean diameter of 28. 13 μm. These microcapsules also have a good thermal stability for long-term use, and have potential applications in minimizing the toxicity of chlorpyrifos through controlled release.  相似文献   

11.
12.
A new type of ionic liquids containing cation of diacetone acrylamide [or N-(1,1-bismethyl-3-oxo-butyl)acrylamide]and anions such as CH3COO^-(Ac),CF3COO^-(TF),BF4^-(BF),PF6^-(PF),HSO4^-(SO) and Cl^-(Cl) were prepared by normal neutralization.The obtained ionic liquids were identified by FT-IR and ^1H NMR spectroscopy.However,their properties such as meliting point,conductivity,viscosity etc,were determined.  相似文献   

13.
The preparation of ZnAlLa-hydrotalcite-like compounds [ZnAlLa-HTLcs] was studied.ZnAlLa-HTLcs were synthesized by a method of variable pH with the raw materials of Zn(NO3)2.Al(NO3)3, La(NO3)3, and NaOH. The effects of some factors (i.e. pH values, the mole ratio of Al^3- to La^3-.temperature and the period of hydrothermal treatment) on the preparation of HTLcs were discussed systematically. XRD. TG-DTA. FT-IR spectroscopy, and ICP were performed to characterize ZnAlLa-HTLcs samples, and the thermal stability of HTLcs was also discussed. It was shown that unique ZnAlLa-HTLcs with high crystallinity can be prepared, under the conditions of pH=5.5-6.5. n(Zn^2 )/n(Al^3 La^3 )=2 and the atomic ratio of La^3 to Al^3 ranging from 0.07 to 2. hydrothermal treatment at 120℃ for 5 h. When the calcination of the HTLcs is performed at temperatures above 200℃. ZnO phase is detected with Al2O3 and La2O3 spreading on its top. The complex metal oxides derived from ZnAlLa-HTLcs at 500℃ have higher catalytic activity and selectivity than those from ZnAl-HTLcs for the esterification of acetic acid with n-butanol under the same reaction conditions.  相似文献   

14.
Synthesis and Characterization of Phosphated Konjac Glucomannan Hydrogels   总被引:11,自引:0,他引:11  
Konjac glucomannan (KGM) was crosslinked with sodium tripolyphosphate (STPP) to synthesize hydrogels. The crosslinking reaction was confirmed by FT-IR. The results of degradation test show that the hydrogels retain the enzymatic degradation character of KGM and can be degraded for 74.45% in 5 days by cellulase E0240.  相似文献   

15.
α-Bromo chalcones containing 2-thiene ring were prepared in good yields by the condensation of 1-(thien-3-yl)ethanone with aromatic aldehydes, followed by bromination with bromine and selective dehydrobromination with triethyl amine at room temperature.  相似文献   

16.
Conjugated Linolenic Acid (CLN) has recently been shown to have a more strong cytotoxic effect on various human tumor cell lines than CLA. In CLN, all the three double bonds are conjugated, whereas they are methylene-interrupted in LN. Some seed oil, such as tung oil and pomegranate seed oil,principally consist of CLN, accounting for 76.5% and 75.5%, respectively. CLN can be characterized using the combination of gas chromatography (GC), high - performance liquid chromatography (HPLC…  相似文献   

17.
Xian  Zhi  DONG  Hui  Bi  Xu 《中国化学快报》2003,14(1):54-57
A novel antimicrobial polypeptide was isoated and characterized from loach,misgurnus anguillicaudatus.The polypeptide,named MAPP,is a single-chain polypeptide with Mw adout 9,800 Dalton and pI about 4.78:the N-tag of MAPP was CFGWN.MAPP showed good inhibition against various bacteria including Bacillus subtilis.Escherichia coli and Staphylococcus aureus.MAPP could be used as a lead compound in antibiotics drug discovery.  相似文献   

18.
It is a new interest to explore novel organic two-photon absorption (TPA) chromophores with large TPA cross section for their potential applications in various fields, such as three-dimensional optical data storage, micro- and nano-fabrication, biological imaging and optical limiting, and so on. As far as asymmetrical D-π-A type chromophores were concerned, larger TPA cross section can be obtained with the enhancement of electron-donation/electron-acception ability.[1] Recently, we have synthesized a series of new D-π-A type compounds. In these chromophores, stilbene or phenyl cyclo-bridged hexatriene is served as π-bridge, which terminated with a number of amino groups and dicyanomethylene unit (Scheme 1). All the chromophores can be obtained by the condensation reaction of aldehydes and active methyl or methenyl groups in good yields (72%~81%). The chromophores have been characterized by 1H NMR,IR, UV-vis, PL and EA. All these five chromophores in dilute solutions show strong red fluorescence (Table 1). The studies on the TPA properties are in progress.  相似文献   

19.
4-(2-Ferrocenylethenyl)-phenyl-POSS Fc-CH=CH-C6H6-(C5H9)7Si8O12 (FEPS, Fc: ferrocene), containing metal and C=C double bond, was firstly synthesized as a mixture of E/Z isomers by the Wittig reaction. The chemical structure of FEPS was characterized by FTIR, 1H-, 13Cand 29Si-NMR.  相似文献   

20.
Mammalian hepatocytes (parenchymal cells) exclusively possess large number ofasialoglycoprotein receptors (ASGPr), which can recognize terminal D-galactose orN-acetylgalactosamine residues. Lactobionic acid 1, bearing a galactosyl group, isusually used as…  相似文献   

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