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161.
Carbon nanotube (CNT) is a novel carbon material discovered by Iijima1. It had beenfound to have the ability to promote electron transfer reactions when it was used tofabricate electrodes for the oxidation of biomolecules2-4. Just recently, the interest indemonstrating CNT for biosensing applications is now emerging5-10. However, most ofthese biosensors were based on CNT paste electrode or CNT modified glassy carbonelectrode by casting technology. Here, we reported another assembly…  相似文献   
162.
由单糖(如果糖、葡萄糖和甘露醇)和H8-2,2'-联萘二酚出发设计和合成了的六个手性单齿亚磷酸酯配体,研究了其铑配合物催化α-脱氢氨基酸甲酯的不对称氢化反应,在1%mol催化剂量和0.12MPaH2下,产物的对映选择性最高达到90.6%e.e.  相似文献   
163.
A new type of aromatic tetraamine containing biphenyl moiety in the side chain was synthesized via a modified Chichibabin's reaction.3-Nitro-4-acetamidoacetophenone was reacted with 4-phenyl benzaldehyde in the presence of ammonium acetate to obtain 2,6-bis(3',4'-diaminophenyl)-4-biphenyl pyridine(DPPA).A series of polypyrrolones(PPys) were prepared using tetraamine and various aromatic dianhydrides via a two-step cyclization procedure.All the PPys show excellent high temperature stabilities with the initial decomposition temperatures of 530-549℃ and residual weight ratio of 49%-80% at 750℃ in nitrogen.The polymers exhibit no apparent glass transition temperatures(T_gs)except PPy-1 (T_g=327℃),which is derived from tetraamine DPPA and 2,2-bis[4-(3',4'-dicarboxyphenoxy)-phenyl]propane dianhydride (BPADA).In addition,the polymers have acceptable mechanical properties with the tensile strength of 65-94 MPa.The PPy films show excellent hydrolysis-resistance in alkaline aqueous medium and could maintain most of the properties even after boiling in 10% aqueous sodium hydroxide solution for a week.  相似文献   
164.
Three New Diarylpropanes from Dioscorea composita   总被引:1,自引:0,他引:1  
Three new diarylpropanes were isolated from the dried rhizomes of Dioscorea composita Hemsl., and their structures were determined as 1, 3-bis-(2-hydroxy-4-methoxyphenyl) propane (1), 1, 3-bis-(2, 4-dihydroxyphenyl)propane (2), 1-(2′-hydroxy-4′-O-β-D- glucopymnosy-phenyl)-3-(2“, 4“-dihydroxyphenyl)propane (3), by spectroscopic analysis, respectively.  相似文献   
165.
A three-way catalyst comprised novel oxygen storage components for emission control in natural gas powered engines was prepared. The addition of novel oxygen storage components to the Pd/γ-Al2O3 catalysts resulted in improved activities of the fresh and aged catalyst by lowering the light-off temperature for methane in natural gas engines exhaust.  相似文献   
166.
A novel liquid crystal compound with a carboxyl group at one end, cholest-5-en-3-ol-(3β) hydrogen decanedioate (1) was successfuly prepared by the reaction of cholesterol with sebacoxl chloride. Its chemical structure and liquid crystalline properties were characterized by FTIR.CNMR,HNMR,POM and DSC. The compound with an active carboxyl group shows themortropic liquid crystalline behaviour.  相似文献   
167.
Polypropylene microporous membranes were treated with plasma in a mixture of N2 and H2 (1:2 in volume). Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and ultra-violet (UV) spectra demonstrated the success of grafting amino groups. The density of the polar amino groups on the membrane surface is about 0.59 μmol/cm^2. The as-treated membranes were successively applied to the in situ synthesis of oligonucleotides and an average coupling yield was more than 98%. The surface feature of the treated membrane is suggested to be responsible for its advantage over a glass slide.  相似文献   
168.
Two new compounds, namely 7α, 10α-dimethyl-3β-isopropene-1, 2-ene-octahydro-naphthalene (1) and ethyl 5Z,8Z, 11Z, 14Z-nonadecatetraenoate (2) were isolated from the soft coralNephthea hainansis. Compound 1 was a pseutosesquiterpene and 2 was a polyunsaturated fattyacid ethylate. Their structures were established on the basis of spectroscopic methods.  相似文献   
169.
This study concentrated on the production of molecularly imprinted polymers (MIPs) as highly selective sorbents for felodipine (FLD), a representive dihydropyridine calcium antagonists. Demonstrated chromatographically through a selection factor, these MIPs showed high selectivity for the template molecule among a group of structurally similar compounds. The recognition was found to correlate with structural similarity to the template compound.  相似文献   
170.
Among the reactions in which C-C bonds are formed, the Baylis-Hillman coupling of aldehydes with α, β-unsaturated carbonylic compounds is currently attracting much interest due to the atom economy, the mild conditions and the generation of functional groups1,2. Furthermore, compared to the Heck, Suzuki and other palladium catalyzed C-C bond forming reaction3, the Baylis-Hillman reaction can be promoted by using organic bases in the complete absence of any metal4. However, almost all the …  相似文献   
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