bluuebunny/crossref_metadata_2025_split huggingface dataset:
High‐Speed Analyzing PCR Products of M. tuberculosis Genome Stained by Ethidium Bromide on Microchip Gel Electrophoresis
Authors: Jin Qing‐Hui , Chen Ji‐Feng , Jing Feng‐Xiang , Zhao Jian‐Long , Xu Yuan‐Sen 
Published: September 2010

AbstractThe technique of microchip gel electrophoresis (MCGE) was used to analyze the polymerase chain reaction (PCR) products of M. tuberculosis Genome stained by ethidium bromide. The electrophoretic process was completed within 3–4 min and the results show that the technique of microchip electrophoresis is a high‐speed and high‐sensitivity analyzing method.
Effects of Template Contents on the Physicochemical Sorption Properties of Zr‐Incorporated Mesoporous Titania Materials
Authors: Zheng Jin‐Yu , Qiu Kun‐Yuan , Wei Yen 
Published: September 2010

AbstractZr‐Incorporated mesoporous titania materials were prepared via nonsurfactant templated sol‐gel process of zirconium (IV) butoxide (ZBT) and titanium (IV) butoxide (TOT) in the presence of urea molecules as template or pore forming agent. The effects of template contents on the pore parameters of the materials synthesized with fixed Zr incorporation contents were investigated by nitrogen adsorption‐desorption measurements, powder X‐ray diffraction (XRD) study and transmission electron microscopy (TEM). The changes of template contents play significant roles on the pore parameters at low incorporation content of Zr. The pore diameters display a dear increase tendency with the increase of template contents. When high Zr incorporation content is used, the template contents have less effect on the pore diameters that almost keep unchanged with the increase of template contents. All the materials possess type IV isotherms with H2 hysteresis loops suggesting the formation of mesophase. The materials with low Zr incorporation content have anatase structures; however, it can not be found in the materials with high Zr incorporation content. TEM images show that some accumulated inter‐particulate pores and well‐distributed worm‐like pores are present in the Zr‐incorporated materials.
Internal Reorganization Energy Contributed by Torsional Motion in Electron Transfer Reaction between Biphenyl and Biphenyl Anion Radical
Authors: Min Wei , Sun Lin 
Published: September 2010

AbstractConcerning the theoretical estimation of internal reorganization energy contributed by the tortional motion between biphenyl and biphenyl anion radical, direct calculation of self‐exchange electron transfer reaction was investigated. With the introduction of a proper average bond length and angle parameters (bond Bp), a multiple step relaxation Nelson method was developed to deal with the torsional reorganization energy. Based on the above model, an estimation of pure torsional reorganization energy λt.p with an approximation of λt.1 was achieved. The results of 0.140 and 0.125 eV of torsional reorganization energy for a cross‐reaction at the levels of 4‐31G and HP/DZP, respectively, are in good agreement with the value of 0.13 eV obtained by Miller et al. from the rate measurements. This implies the efficiency and validity of our method to estimate the reorganization energy contributed by pure torsional motion of Bp.
Hyperspherical Harmonic Expansions of Potential 1/rjt of Molecular Systems
Authors: Wu Ai‐Ling , Liu Cheng‐Bu , Zhao Xian , Bian Xiu‐Fang 
Published: September 2010

AbstractThe expansion coefficient CD|L| of Coulomb potential 1/rjt of molecular systems in hyperspherical harmonics is derived in detail, and the explicit expression is given.
Theoretical Study on Electron Transfer Matrix Element in Oxidation of α ‐ Amino Carbon‐Centered Radical by O2
Authors: Liu Ji‐Feng , Zhu Quan , Li Xiang‐Yuan , Yang Sheng‐Yong 
Published: September 2010

AbstractAs a successive work of our previous paper,1 the electron transfer matrix element (Vrp) in the oxidation of the simplified model molecule of α‐amino carbon‐centered radical by O2 has been investigated with ab initio calculation at the level of UHF/6‐31 + + G*. Based on the optimized geometries of the reactant and the ion‐pair complex obtained previously, the reaction heat and the inner reorganization energy have been obtained by constructing the potential energy curves of reactant and product states considering the solvent effect with the conductor‐like screening model (COSMO). The solvent reorganization energy has been estimated using Lippert‐Mataga relationship. The calculated results show that the value of Vrp, is several times larger than that of RT, which means that the model reaction is an adiabatic one. Theoretical investigation indicates that the solvent effect on the direct electron transfer (ET) process of oxidation of α‐amino carbon‐centered radical by oxygen is remarkable.
Determination of Ascorbic Acid Using a New Oscillating Chemical System of Lactic Acid‐Acetone‐BrO3−‐Mn2+‐H2SO4
Authors: Yang Shu‐Tao , Lin Zhi‐Xin , Cai Ru‐Xiu , Gan Nan‐Qin 
Published: September 2010

AbstractAnalyte pulse perturbation (APP) technique was applied to the study of the perturbation of ascorbic add (AA) on the lactic add‐acetone‐BrO3−‐Mn2+‐H2SO4 oscillating reaction, and AA was determined using this new oscillating chemical system. Influence of experimental variables was investigated. The linear range lies between 5.0 × 10−7‐5.5 × 10−s mol/L, and the precision and throughput were quite good (2.43% as RSD, and 8–10 samples/h, respectively). This method was applied to the determination of real samples and the results were satisfactory. Some aspects of the potential mechanism of action of AA on the oscillating systems are discussed.
Detection of Tumor Necrosis Factor Gene by Piezoelectric Nucleic Acid Sensor
Authors: Hu Yi , Zhou Xtao‐Dong , Liu Li‐Jia , Hu Min , Pei Ren‐Jun , Hu Ji‐Ming 
Published: September 2010

AbstractA piezoelectric nucleic acid sensor was constructed for detection of tumor necrosis factor gene. Two methods were employed for immobilization of nucleic add probe on gold electrode of piezoelectric crystal. The results show that polyethyleneimine adhesion and glutaraldehyde cross‐linking method has higher sensitivity, stability and selectivity than protein A method. The solid‐phase nucleic acid hybridization of oligo nucleotides and tumor necrosis factor target gene sequence were monitored using this sensor. Tumor necrosis factor gene sequence (580 bp) was detected by mis nucleic acid sensor for the first time.
Simultaneous Laser Thermal Lens Spectrometric Determination of Trace Platinum and Palladium in an Aqueous Solution
Authors: Zhang Xiao‐Ling , Yan Hong‐Tao 
Published: September 2010

AbstractA selective and sensitive method for determination of platinum and palladium (II) in an aqueous solution simultaneously by laser thermal lens spectrometry, based on the complex reaction of 2‐(3,5‐dichlopyridylazo)‐5‐dimethylaminoamiline (3,5‐di‐O‐PADMA) with platinum and palladium, has been developed. It is shown that the palladium complex can be formed at room temperature, while the platinum complex can be only formed after being heated in a boiling water bath. By using this difference of reaction temperature and the characteristic of the complexes mentioned above, the method for simultaneous determination of platinum and palladium was established in an aqueous solution without a pre‐separation. The results show that the dynamic linear ranges of determination for platinum and palladium are 0.005–0.04 μg/mL and 0.005–0.25 μg/mL respectively, and that the detection limits are both 0.002 μg/mL. The method has been applied to the determination of platinum and palladium simultaneously in alloy and catalyst samples with satisfactory results.
Synthesis of New Spiropyrans With a Polyaromatic or Heteroaromatic Pendant and Their Photochromic Behaviors
Authors: Pang Mei‐Li , Nie Yun‐Tong , Wang Yong‐Mei , Meng Ji‐Ben , Wang Ji‐Tao 
Published: September 2010

AbstractA series of spiropyrans with a polyaromatic or heteroaromatic pendant was synthesized conveniently. Their photochromic behaviors were investigated with the aid of absorption spectral measurements. The results indicated that the compounds with the same parent spiropyran but different aromatic pendant show significantly different photochromic properties. This may be due to the π‐π orbital interaction between the polyaromatic pendant and the open photomerocyanine form of spiropyran. The results obtained are very useful in the molecule design area.
Negative Feedback Effect of Microwave Irradiation in the Microwave‐assisted Hydrothermal Synthesis of Bi2S3 Nanorods
Authors: Tao Xiu‐Cheng , Shao Ming‐Wang 
Published: September 2010

AbstractThe microwave‐assisted hydrothermal synthesis of Bi2S3 nanorods was reported. The result showed that microwave irradiation can help to produce Bi2S3 nanorods in very short time. There is a negative feedback effect which increases the degree of crystallinity in the reaction.
Synthesis and Crystal Structure of a Novel Hydrogen‐Bonded Three‐Dimensional Polymer [Zn (1,4‐benzenedicarboxylate) ‐(pyridine)·H2O]n
Authors: Wang Rui‐Hu , Hong Mao‐Chun , Weng Jia‐Bao , Cao Rong , Luo Jun‐Hua 
Published: September 2010

AbstractA zinc(II) complex [Zn(bdc)(py)·H2O]a (bdc=1,4‐benzenedicarboxylate, py=pyridine) has been prepared and characterized. Single crystal X‐ray diffraction analysis reveals that the complex crystallizes in the monoclinic space group P21/n with a = 0.84823(3), b = 0.91440(3), c = 1.65141(2) ran, β = 91.243(2)°, V= 1.28057(6) nm3, Z = 4. The coordination geometry at each Zn(II) center is a distorted tetrahedron. Two independent bdc ligands in a herringbone pattern link alternatively four‐coordinated Zn(II) centers into a one‐dimensional polymeric chain. Hydrogen bonds among coordinated water molecules and uncoordinated oxygen atoms of two independent bdc ligands from different polymeric chains extend one‐dimensional polymeric chains into a three‐dimensional structure.
A Versatile Approach for the Asymmetric Synthesis of 3‐Alkyl‐isoindolin‐1‐ones
Authors: Chen Ming‐De , He Ming‐Zhu , Huang Li‐Qiang , Ruan Yuan‐Ping , Huang Pei‐Qiang 
Published: September 2010

AbstractA flexible approach to (R)‐3‐alkyl‐isoindolin‐1‐ones and (R)‐3‐aryl‐isoindolin‐l‐ones via a diastereoselective reductive‐alkylation is described. Present method is versatile in scope, allowing the easy introduction of various C‐3 substituents by Grignard addition to phthalimide derived from (R)‐phenylglycinol. 3‐Alkyl‐3‐hydroxy‐isoindolin‐1‐ones can also be obtained in the first step of the present method.
Multifunctional Molecular Material Combining Photocurrent Generation and Second‐Order Optical Nonlinearity in LB Monolayer Films†
Authors: Li Fu‐You , Huang Yan‐Yi , Huang Chun‐Hui , Jin Lin‐Pei , Zhao Xin‐Sheng , Liu Ting‐Ting 
Published: September 2010

AbstractA novel amphiphilic stilbazolium dye, (E)‐N‐methyl‐4‐[2‐(4‐N‐methyl‐N‐hexadecylaminophenyl) ethenyl]‐2‐isoquinolinium iodide (MHIQ), was synthesized. The dye was successfully transferred onto ITO electrode or quartz by the Langmuir‐Blodgett (LB) technique. The second harmonic generation (SHG) and photocurrent generation properties of the LB film transferred under 35 mN/m of surface pressure were investigated. The broad absorption maximum of the LB monolayer of MHIQ at 434 nm is far away from the wavelength (532 nm) of resonant enhancement effect, and its second harmonic susceptibility x(2) is 167 pm/V, which means that the isoquinolinium is a good electron‐accepting group. The photocurrent generation experiment shows that the photocurrent generation properties are dependent on the experimental conditions including bias voltage, redox couples and light intensity. By a light irradiation at 440 nm, the photocurrent generation quantum yields of the dye LB monolayer are 0.50% in 0.5 mol/L KG electrolyte solution and 17.5% in 0.1 mol/L KI electrolyte solution with 0.01 mol/L I2, respectively, indicating that the dye MHIQ is a good photoelectric conversion material.
Kekulé‐based Valence Bond Model. I. The Ground‐state Properties of Conjugated 7ü‐Systems
Authors: Li Shu‐Hua , Ma Jing , Jiang Yuan‐Sheng 
Published: September 2010

AbstractThe Kekulé‐based valence bond (VB) method, in which the VB model is solved using covalent Kekulé structures as basis functions, is justified in the present work. This method is demonstrated to provide satisfactory descriptions for resonance energies and bond lengths of benzenoid hydrocarbons, being in good agreement with SCF‐MO and experimental results. In addition, an alternative way of discussing characters of localized substructures within a polycyclic benzenoid system is suggested based upon such simplified VB calculations. Finally, the symmetries of VB ground states for nonalternant conjugated systems are also illustrated to be obtainable through these calculations, presenting very useful information for understanding the chemical behaviors of some nonalternant conjugated molecules.
Kekulé‐based Valence Bond Model. II. Diels‐Alder Reactivity of Polycyclic Aromatic Hydrocarbons
Authors: Ma Jing , Li Shu‐Hua , Jiang Yuan‐Sheng 
Published: September 2010

AbstractThe Kekulé‐based valence bond (VB) method was employed to study the ground state properties of 52 polycyclic aromatic hydrocarbons. The reactivity indices defined upon our VB calculations were demonstrated to be capable of quantitatively interpreting the second order rate constants of the Diels‐Alder reactions. The qualitative trends of the reactivities of many homologous series can be also explained based on the local aromaticity index defined in this work.
Characterization and Dehydrogenation Activity of SBA‐15 and HMS Supported Chromia Catalysts†
Authors: Yue Hong‐Yong , Zheng Bo , Yue Ying‐Hong , Zhang Xue‐Zheng , Hua Wei‐Ming , Gao Zi 
Published: September 2010

AbstractSBA‐15 and HMS supported chromia catalysts were prepared and characterized. Chromia is highly dispersed on the mesoporous supports when its loading is 7 wt%. The supported catalysts display high activity, selectivity and stability for dehydrogenation of ethylbenzene and propane. ESR measurement of the catalysts before and after reaction shows that the active species for dehydrogenation reaction might be Cr3+ species on the catalyst surface, and the activity of the catalyst is probably correlated with the dispersion of Cr3+ species.
Synthesis and Characterization of a Series of New Functional Poly(ferrocenylenesilanes) for Nonlinear Optics
Authors: Liu Yun‐Yang , Zhang Xuan , Tang Hong‐Ding , Wang Ting‐Juan , Qin Jin‐Gui , Liu Dao‐Yu , Li Shao‐Jnn , Ye Cheng 
Published: September 2010

AbstractA series of new poly (ferrocenylenesilanes) containing carbazole as charge transporting agent and Dispersed Red 1 (DR‐1) as second‐order nonlinear optical (NLO) chromophore was synthesized. The resulting polymers represent the first example of NLO polymer with ferrocenyl groups in the backbone. This series of polymers was characterized with 1H NMR, LTV‐vis, IR spectroscopies, differential scanning calorimeter (DSC) and gel permeation chromatography (GPC). A preliminary measurement on NLO property of the polymers was carried out with in‐situ second‐harmonic generation (SHG) measurement.
Studies on the Intramolecular Inclusion Complexes of Functionalized Calix[4]arenes with CH3X (X = CN, NO2)
Authors: Zhou Zhi‐Xian , Shi Ya‐Lin , Du Chen‐Xia , Xing Yan‐Jun , Wu Yang‐Jie 
Published: September 2010

AbstractTwo functionalized calix[4]arenes in cone conformation L2–3 have been synthesized and their intramolecular inclusion complexes (1:1) with organic neutral molecules CH3CN and CH3NO2 have been prepared and characterized, respectively. The X‐ray crystallographic analysis shows that L2 in L2·CH3CN. C2H5OH has C4 symmestry and L3 in L3.CH3NO2 exhibits C2 symmestry. The CH‐π aromatic interactions between the CH group of the guest and the phenyl rings of the calix backbond have been proved to be able to stabilize the intramolecular inclusion complexes formed. The interaction is directional, but it is independent of the acidity of the guest. To gain information on CH‐s interactions, suitable geometrical parameters have been calculated from the crystal data of intramolecular inclusion complexes. The results show that L3.CH3NO2 with L3 in C2 symmestry can also be bound stably in the intramolecular inclusion complex, being consistent with the thermal analysis. The geometrical parameters and the results of the thermal analysis of L1.CH3CN and L1.CH3NO2 were also given and discussed.
Proline‐40 is Essential to Maintaining Cytochrome b5′ s Stability and Its Electron Transfer with Cytochrome c
Authors: Wang Zhi‐Qian , Wu Jian , Wang Yun‐Hua , Qian Wen , Xie Yi , Xia Zong‐Xiang , Huang Zhong‐Xian 
Published: September 2010

AbstractIn order to illustrate the roles played by Pro40 in the structure, properties and functions of Cytochrome b5, three mutated genes, P40V, P40Y, P40G were constructed in this work. Only the P40V gene was successfully expressed into holoprotein in E. coli JM83. According to the results of X‐ray crystallographic analysis and various kinds of spectroscopy studies, it is evident that substituting valine for Pro40 does not result in significant alterations in the protein′s overall structure; however, local conformational perturbations in the proximity of the heme do occur. The redox potential of the P40V mutant is 40 mV lower than that of the wild type protein. Its stability towards heat, urea, acid and ethanol were significantly decreased. The mutation leads to a decrease in the hydrophobicity of the heme pocket, which is probably the major factor contributing to the above changes. Binding constants and electron transfer rates between cytochrome bs and cytochrome c were determined using UV‐visible spectroscopy and stopped‐flow techniques for both the wild type and the mutant. The results showed that the substitution of Pro40 by valine does not influence the binding constant of cytochrome b5 to cytochrome c; however, the electron transfer rate between them decreased significantly. This indicates that proline‐40 is essential to maintaining cytochrome bss stability and its electron transfer with cytochrome c. These studies also provided a good example that property and functional changes of a protein do not necessarily require large overall structural alterations; in most cases, only perturbations on the local conformations are sufficient to induce significant changes in protein′s properties and functions.
Synthesis of Optically Active β ‐ Alkyl ‐ α ‐ methylene ‐ δ ‐ butyro ‐lactones from Enantioselective Biotransformation of Nitriles, an Unusual Inversion of Enantioselectivity†
Authors: Zhao Sheng‐Min , Wang Mei‐Xiang 
Published: September 2010

AbstractA new approach to optically active β‐alkyl‐α‐methylene‐δ‐butyrolactone derivatives was reported from the Rhodococcus sp. AJ270‐catalyzed hydrolysis of appropriate nitriles. The inversion of enantioselectivity of the amidase has been observed when a methyl protection was introduced into the hydroxy group of the parent substrate.
Axially Dissymmetric Chiral (R)‐N, W‐Bis(2‐hydroxy‐3,5‐ditert‐butyl‐arylmethyl)‐1, 1′‐binaphthalene‐2,2′‐diamine as Chiral Ligands in the Reaction of Diethylzinc to Aldehydes†
Authors: Shi Min , Duan Wei‐Liang , Rong Guo‐Bin 
Published: September 2010

AbstractChiral ligand (A)‐N,N′‐Bis(2‐hydroxy‐3,5‐di‐tert‐butyl‐arylmethyl)‐1,1′‐binaphthalene‐2,2′‐diamine derived from the reduction of Schiff base (R)‐2,2′‐bis (3,5‐di‐tert‐butyl‐2‐hydroxybenzylideneamino)‐1, 1′‐binaphthyl with LiAlH4, is fairly effective in the asymmetric addition reaction of diethylzinc to aldehydes by which good yields (46%‐94%) of the corresponding sec‐alcohols can be obtained in moderate ee (51%‐79%) with R configuration for a variety of aldehydes.
A Convenient Synthesis of 2‐Aryl‐3‐per(poly) fluoroacylindoles
Authors: Liu Jin‐Tao , Liu He‐Jun 
Published: September 2010

Abstract2‐Aryl‐3‐per(poly) fluoroacylindoles were synthesized in good yields by the 1,3‐dipolar cycloaddition reaction of C‐aryl‐N‐phenylnitrones with fluorine‐containing olefins and the subsequent rearrangement of the adducts. An ionic mechanism was proposed for the formation of the titled compounds.
Catalytic Cyclotrimerization of Arylnitriles Using the Novel Samarium (II) Complexes as Catalysts
Authors: Xu Fan , Zhu Xue‐Hua , Shen Qi , Lu Jun , Li Jiu‐Qin 
Published: September 2010

AbstractSamarium(II) complexes or Samarium(II) complexes/n‐hexylamine systems were found to be efficient catalysts for cyclotrimerization of arylnitriles. A variety of nitrites can be converted into the corresponding substituted‐s‐triazines under mild conditions in good to high yields by using samarium (II) complexes/n‐hexylamine as catalysts. The same reaction catalyzed by samarium(II) complexes alone gives s‐triazines in moderate yields.
A Concise Approach to the Synthesis of L‐ and Z)‐Deoxyribose
Authors: Hu Shou‐Gang , Wu Yi‐Kang , Wu Yu‐Lin 
Published: September 2010

AbstractD‐Deoxyribose, the basic structure unit of DNA, and its antipode L‐deoxyribose were concisely synthesized from easily available D‐ and L‐glyceralaldehydes using a known convenient diastereoselective propargylation as the key step.
Homo‐ and Copolymerization of ε‐Caprolactone and 2,2‐Dimethyltrimethylene Carbonate by Rare Earth Initiators
Authors: Shen Zhi‐Quan , Zhu Gui‐Xiang , Ling Jun 
Published: September 2010

AbstractRare earth tris(2,6‐di‐tert‐butyl‐4‐methylphenolate) [Ln‐(OAr)3, Ln = La, Nd, Dy, Y] alone has been developed to initiate polymerization of e‐caprolactone (CL) and random copolymerization of CL with 2, 2‐dimethyltrimethylene carbonate (DTC). The structures of polymers were analyzed by GPC, ER and NMR methods. Their crystal and thermal properties were discussed in terms of DSC. The initiating efficiencies were mainly affected by the size of rare earth metal in the sequence of La(OAr)3 > Nd(OAr)3 ∼ Y(OAr)3 > Dy(OAr)3. La‐(OAr)3 exhibited rather high activity to prepare PCL with a molecular weight of 2.15 × 105 and Ma/Ma of 2.27. The composition of random copolymer can be quantitatively controlled either by reaction time or by feed ratio of monomer.
Reaction of Grignard Reagents with Diethyl Perfluoroacyl (1‐Cyanoethyl) phosphonates. Synthesis of Perfluoroalkylated α, β‐Unsaturated Nitriles with Predominant Z‐Selectivity
Authors: Shen Yan‐Chang , Jiang Guo‐Fang 
Published: September 2010

AbstractDiethyl (1‐cyanoethyl) phosphorate 1 was reacted with n‐butyl‐lithium in tetrahydrofuran (THF) at ‐ 78 °C and the resulting carbanion 2 reacted with perfluoroalkanoic add anhydride to afford perfluoroacylated phosphorate 3. Without isolation 3 was attacked by Grignard reagents giving perfluoroalkylated α, β‐unsaturated nitriles in 46%‐88% yields with high Z‐stereoselectivity (Z: E = 89–62:11–38).
Studies on Synthesis and Intramolecular Catalyzed Hydrolysis of Thiophosphoramidate Derivatives of Nucleoside
Authors: Miao Zhi‐Wei , Fu Hua , Feng Yu‐Ping , Han Bo , Tu Guang‐Zhong , Zhao Yu‐Fen 
Published: September 2010

AbstractNovel thiophosphoramidate derivatives of nucleoside analogue as membrane‐soluble prodrugs of the bioactive free nucleotides have been prepared by thiophosphorylation reaction. 2′,3′‐O,O′‐Isopropylidene uridine‐5′‐ylN‐thiophosphoryl serine and threonine methyl esters underwent the intramolecular catalyzed hydrolysis reaction.