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111.
甲酰胺对有序介孔二氧化硅形貌的影响   总被引:2,自引:0,他引:2  
At room temperature and in acidic solution, ordered mesoporous silicas with particular morphology were synthesized using cetylpyridinium chloride as the template and formamide as the cosolvent. Scanning electron microscope (SEM), small angle X-ray diffraction (SXRD), and nitrogen adsorption techniques were used to characterize the as-synthesized and calcined samples. Results showed that the samples had hexagonal mesostructure analogous to MCM-41 and relatively narrow pore-size distributions (BJH). Besides, BET surface areas of the samples were in the range of 1 000~1 250 m2·g-1 and high total pore volumes were up to 1.367 cm3·g-1. Addition of formamide affected obviously mesostructures and the morphology of the mesoporous silica. Furthermore, with the increase of the concentration of formamide, the unit-cell constant decreased and particle shape changed from gyroids to fibers.  相似文献   
112.
A new sesquiterpene lactone, Ainsliaolide A, was isolated from Ainsliaea bonatii. The structure was determined on the basis of spectral data.  相似文献   
113.
纳米氧化铜的制备及常温脱硫效能研究   总被引:3,自引:0,他引:3  
闫波  王新  邵纯红  李芬  姜安玺 《无机化学学报》2007,23(11):1869-1874
采用硝酸铜为原料、氢氧化钠溶液为沉淀剂、使用体积比为1∶1的乙醇-水溶液为分散剂的直接沉淀法制备,通过改变工艺条件得到了三种纳米氧化铜产品,平均粒径分别为25.63,10.74和7.57 nm。采用TG-DTA、FIR、XRD和TEM等对纳米氧化铜进行表征。对产品的常温脱硫活性进行了穿透试验,并与已开发的其他常温精脱硫产品进行了比较,结果表明纳米氧化铜应用于H2S脱硫,可在常温条件下具有优异的脱硫活性,对H2S的脱除精度可以达到0.05 mg·m-3以下。经过优选,产品在3 000 h-1空速下穿透硫容达到25.3%,高于同类型的其他脱硫剂产品。  相似文献   
114.
a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] and iron(III) chloride hexahydrate can be quantitatively recovered and be reused effectively for many times. Compared with the known methods, this novel process has the advantage of being an envkonmentally benign process together with good yields and mild reaction conditions.  相似文献   
115.
微乳液法制备超细K2Ln2Ti3O10及其光催化活性研究   总被引:1,自引:4,他引:1  
以钛酸四丁酯、氢氧化钾和镧系金属氧化物为原料。采用微乳液法制备了系列超细K2Ln2Ti3O10(Ln=La.Ce,Pr.Nd,Sm,Eu,Gd)光催化剂。并考察了其光催化活性。通过X射线衍射(XRD)、透射电镜(TEM)和紫外可见吸收光谱(UV—Vis)对其进行了表征。结果表明:用微乳液法制备催化剂可以在较低的温度下(900℃),用较短的烧结时间(3h)合成结晶度高、粒径较小(200Mm)的K2Ln2Ti3O10钙钛矿型层状结构化合物。催化剂在紫外光和可见光条件下均具有光催化降解甲基橙的活性。紫外光条件下可以明显提高光催化降解活性,降解率达到60%。  相似文献   
116.
This work describes a study of the underpotential deposition (UPD) of Sn2+ on a polycrystalline gold disc electrode using cyclic voltammetry (CV) and chronocoulometry (CC). Sn2+ ions showed well-defined peaks from UPD and UPD stripping (UPD-S) in 1 mol/L HCl solutions, while bulk deposition (BD) and BD stripping (BD-S) of the ions were also observed. The measured UPD shifts, EUPD, between the UPD-S and the BD-S peaks were more than 200 mV. The UPD charge and the surface coverage of tin were measured by CC. A new method for determining Sn2+ was therefore developed, based on the excellent electrochemical properties of the Au/Sn UPD system. A plot of the UPD-DPASV (differential pulse anodic stripping voltammetry) signal versus the Sn(II) concentration was obtained for [Sn(II)] of 1.98×10–7 to 3.64×10–5 M. The method developed here has been applied to determine the tin in a tin plate sample.  相似文献   
117.
Solvent-free organic reactions have been attracting great interest of chemists due to the elimination of the usage of harmful organic solvents,low costs,and simplicity in the procedure1.Solvent-free mechanochemical reactions of fullerenes were explored and are significant for the reactions of fullerenes because the low solubility of fullerenes in common organic solvents requires large quantity of organic solvents and some novel fullerene reactions could only occur in the solid-state reaction2.…  相似文献   
118.
The interactions of serum albumins such as human serum albumin (HSA) and bovine serum albumin (BSA) with emodin, rhein, aloe-emodin and aloin were assessed employing fluorescence quenching and absorption spectroscopic techniques. The results obtained revealed that there are relatively strong binding affinity for the four anthraquinones with HSA and BSA and the binding constants for the interactions of anthraquinones with HSA or BSA at 20 degrees C were obtained. Anthraquinone-albumin interactions were studied at different temperatures and in the presence of some metal ions. And the competition binding of anthraquinones with serum albumins was also discussed. The Stern-Volmer curves suggested that the quenching occurring in the reactions was the static quenching process. The binding distances and transfer efficiencies for each binding reactions were calculated according to the F?ster theory of non-radiation energy transfer. Using thermodynamic equations, the main action forces of these reactions were also obtained. The reasons of the different binding affinities for different anthraquinone-albumin reactions were probed from the point of view of molecular structures.  相似文献   
119.
硫代钼酸盐和硫代钨酸盐的合成性质和取代反应的研究   总被引:2,自引:0,他引:2  
本文提出了在水或水/醇溶液中[NH_4]_2[MO_nS_(4-n)](M=Mo、W,n=0-2)进行取代反应的方法。用该方法合成出[X]_2[MO_nS_(4-n)](X=(n-Bu)_4N、Ph_4P、py—C_(16)H_(33)共18个化合物,其中11个为新化合物,并采用元素分析、红外光谱、电子光谱和X-粉末衍射等方法对这些化合物进行了表征。  相似文献   
120.
<正> 以金属钠作催化剂合成的聚砜-尼龙6嵌段共聚物对尼龙6的吸水性有一定的改善,而且可以作为聚砜与尼龙共混物的相容剂,但共聚物中聚砜组分的含量都不超过25%。这可能与共聚物的结构有关。近年来的工作表明:反相气相色谱法(IGC)是高聚物结构分析的有用的工具之一。我们试图用反相气相色谱法,通过观察嵌段共聚物  相似文献   
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