Fluoride and lead adsorption on carbon nanotubes

The properties and applications of CNT have been studied extensively since Iijima discovered them in 1991[1,2]. They have exceptional mechanical properties and unique electrical property, highly chemical stability and large specific surface area. Thus far, they have widely potential applications in many fields. They can be used as reinforcing materials in composites[3], field emissions[4], hydrogen storage[5], nanoelectronic components[6], catalyst supports[7], adsorption material and so on.…     

Uniform Rice-like CdS Particles Prepared from Water-in-oil Microemulsions

IntroductionNano-sized semiconductors are of great interestdue to their special optical and electronic proper-ties[1,2].As one of the mostimportantⅡ—Ⅵsemicon-ductors,CdS has importantapplications in many fields,such as the solar cell field,non linear o…     

Co-C bond dissociation energy and reaction volume change of 2',5'-dideoxyadenosylcobalamin studied by laser-induced time-resolved photoacoustic calorimetry

Time resolved photoacoustic calorimetry (PAC) was applied to a study of the photolysis of a coenzyme B(12) analog 2',5'-dideoxyadenosylcobalamin, which lacks an -OH group at the 2' position of ribofuranose ring. In aqueous solution, we report for the first time the quantum yield Phi(d) (0.25+/-0.02), Co-C bond dissociation energy (BDE; 31.8+/-2.5 kcal mol(-1)) and reaction volume change deltaV(R) (6.5+/-0.5 ml mol(-1)) due to conformation changes of the corrin ring and its side chains accompanying the cleavage of the Co-C bond. These values for the analog are very similar to those for the natural cofactor. Based our results and previous studies, a possible explanation for the similarity in their structure and properties versus the large difference in their enzymatic activity is discussed.     

Chemical Constituents and Antibacterial and Antifungal Activities of Two Aglaia Species

In the course of searching bioactive natural products from the plant genus Aglaia, we selected two species, A. cordata and A. testicularis, for further chemical study. Totally twenty natural compounds were obtained and structurally elucidated with which eleven of them were discovered for the first time. Among these compounds, lignans, rocaglamides,aglains and bisamides were the main constituents of the two plant species. The results from a bioactive screening indicated that some of the lignans possess potent antibacterial and antifungal activity.     

Preparation and Characteristics of Porous Silica Films by a Modified Base-Catalyzed Sol-Gel Process Containing PVA: II. Film Preparation

Porous SiO₂ films were successfully deposited on silicon substrates by a modified base-catalyzed Sol-Gel process (MBCP) containing polyvinyl alcohol (PVA). The process conditions, such as the gelation time, the synthesis temperature, the stabilizing agent of the precursor solution and the spin coating speed, the heat-treatment, the annealing temperature of the film on the microstructure and porosity of porous SiO₂ films were systematically investigated by SEM, XRD and ellipsometry techniques. This study provides a novel preparation technique for the porous SiO₂ film. Using this process, the resultant film can reach a thickness of 3.6 m for one layer, a porosity of 25–50%, a low thermal conductivity of 0.11 W/m·K. This film will be used as a low dielectric layer, an thermal-insulating layer and a low refractive index layer.     

Ni的掺入对复合氧化物LaFeO3的结构及性质的影响

合成子Ｎｉ替代铁酸稀土复合氧化物ＬａＦ３１－ｘＮｉｘＯ３（ｘ＝０．１－０．６），对样品进行了ＸＲＤ、ＩＲ及Ｍｏｓｓｂａｕｅｒ谱测试，结果表明：ｘ＝０＼１，０＼２，０＼３的样品为正交相，ｘ＝０．５，０．６的样品为菱方相；伴随相结构从正交向菱方结构的转变，ＩＲ谱上Ｆｅ（Ｎｉ）－Ｏ键伸振动谱带向高频移动近２０ｃｍ＾－１，Ｍｏｓｓｂａｕｅｒ谱测试表明Ｆｅ均处于＋３自旋态，Ｎｉ离子以＋３价进入晶格。     

Relationship between Structure and SHG Effect of Substituted Thienyl Chalcone

1INTRODUCTIONRecentlyorganicnonlinearoptical(NLO)materialsarebeingdevelopedforfre-quencyconversionoflaserinopto-electrics-Especiallybluelightisrequiredforopti-calmemoryofhighdensityrecording.Becauseadiodelaserisusedasalightsource,thenonlinearmaterialswhichhaveextremelyhighvalueofNLOcoefficientsandthetransmissionofblueregionarenecessary.Sincethesecond-orderNLOpropertyoforganiccompoundisderivedfromconjugateddelocalizedrrelectrons,thecompoundswhichhavebeenreportedhavefocusedonthenitroanil…     

An Efficient Method for the Synthesis of Acyl-diazenes Using NaNO_2/NaHSO_4·H_2O

Azo compounds are widely utilized as analytic reagents and dyes1, they can also be used in material of non-linear optics, material of optics information storing in laser disks, and dyes with oil solubility in photochromy in modern technology2. Recently, many noteworthy studies have shown that some azo compounds possess excellent optical memory and photoelectric properties3,4. For example, polymer scaffolds bearing azobenzene-potential are useful for optical information storage, azo-dye doped…