正极材料Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti，Al；x=0，0.02)电化学行为的比较研究

0IntroductionMany efforts have been made to develop newmaterials as an alternative to LiCoO2due to the rela-tively high cost and toxicity of Co.Much attention hasbeen paid to layered structure cathode materials suchas LiMnO2and LiNiO2due to their lower co…     

Aqueous Media Oxidation of Alcohols with Ammonium Persulfate

Oxidation of series of various primary and secondary alcohols to corresponding carbonyl compounds with ammonium persulfate in aqueous media was described. No over oxidation of primary alcohols to carboxylic acids and secondary alcohols to esters was observed. Under such conditions benzoin was converted to benzoic acid.     

Using factor analysis scales of generalized amino acid information for prediction and characteristic analysis of β-turns in proteins based on a support vector machine model

This paper offers a new combined approach to predict and characterize β-turns in proteins.The approach includes two key steps,i.e.,how to represent the features of β-turns and how to develop a predictor.The first step is to use factor analysis scales of generalized amino acid information(FASGAI),involving hydrophobicity,alpha and turn propensities,bulky properties,compositional characteristics,local flexibility and electronic properties,to represent the features of β-turns in proteins.The second step is to ...     

SmI_2-Mediated Addition Reaction of α-Halomethylsulfones to Carbonyl Compounds.A Convenient Synthesis of β-Hydroxysulfones

Due to the chemoselective dehalogenation by SmI_2, the additionof α-halomethylsulfones to carbonyl compounds afforded β-hy-droxysulfones. Those reactions with α-bromomethylsulfonesgave the products in moderate to good yields. The SmI_2-mediat-ed addition of gem-dihalomethylsulfones to ketones also afford-ed α-halo-β-hydroxysulfones in moderate yields.     

Impact Factor of Chinese Journal of Catalysis increases from 1.171 to 1.304—congratulations and thanks to the authors of our most cited articles

According to the Thomson Reuter report on 20 June 2013, the 2012 Impact Factor of Chinese Journal of Catalysis has improved from 1.171 to 1.304. Chinese Journal of Catalysis would like to express our congratulation and appreciation to all the authors who have been part of this success by publishing their good contribution in the Journal.     

Novel Chiral Ferrocenyl Aziridino Alcohol Catalysts Promoting Asymmetric Addition of Diethylzinc to Aldehydes

Optically active aziridino alcohols containing ferrocenyl groups were prepared from commercially available L-threonine in excellent yields and used as catalysts to promote the asymmetric addition of diethylzinc to aryaldehydes to afford 1-arylpropanol in up to 84% enantiomeric excesses with moderate to good yields.     

Non-fullerene acceptor pre-aggregates enable high efficiency pseudo-bulk heterojunction organic solar cells

Pseudo-bulk heterojunction(BHJ)fabricated by sequential casting of donor and acceptor layers has been recently demonstrated as a superior structure to prepare organic solar cells(OSCs)with enhanced efficiency compared to the conventional BHJ OSCs cast from a common solution of donors and acceptors.However,molecular diffusion and aggregation within the pseudo-BHJ layer bring great challenges to fully realize the advantage of pseudo-BHJ structure.Herein,a solution-incubated pre-aggregation strategy is employed to tune the nanoscale aggregates of non-fullerene acceptor(NFA)BTP-e C11 and N3 to substantially enhance device power-conversion efficiency(PCE).NFA pre-aggregates are incubated in solutions via aging or adding antisolvent,and then sequentially cast onto D18 fibrillar network,which then penetrate to form a pseudo-BHJ structure with appropriate domain sizes to ensure superior charge mobilities.While the conventional pseudo-BHJ OSCs obtain inferior PCEs below 17%compared with normal BHJ OSCs,NFA pre-aggregates help to achieve remarkable PCEs of 17.7%and 17.5%for D18/BTP-e C11 and D18/N3 pseudo-BHJ OSCs.This work demonstrates that the solution-incubated nanoscale pre-aggregation is an efficient approach to regulate molecular diffusion and aggregation to guarantee high performance pseudo-BHJ OSCs.     

Effect of Pd or Ir on the catalytic performance of Mo/H-ZSM-5 during the non-oxidative conversion of natural gas to petrochemicals

Natural gas conversion to petrochemicals, principally, benzene, naphthalene, toluene, as well as ethylene under non-oxidative conditions was examined in a fixed bed flow reactor at 700 ℃ and gaseous hourly space velocity （GHSV） of 1500 ml·g ^-1·h^-1 at time-on-stream ranging from 5 rain to 4 h using catalysts containing 6.0%Mo/H-ZSM-5 promoted with Pd or Ir metal. The catalysts were characterized by XRD, TPD, and TGA. The addition of Pd or Ir to 6%Mo/H-ZSM-5 catalyst promoted ethylene production but inhibited the cyclization reaction to aromatics owing to the strong interaction between these noble metals and the framework Al species, which were attached to the acid sites during the impregnation process. Coke deposition on the catalysts was found to decrease upon addition of 0.5wt% of Pd or Ir to 6%Mo/H-ZSM-5 catalyst owing to the hydrogenating activity of these metals.     

Journal of Natural Gas Chemistry begins to come off the press bimonthly in 2010

Natural gas occupies an increasingly important position in the structure of global energy resources.In order to adapt to the fast developments in natural gas chemistry and hydrogen energy, and to accelerate     

Synthesis and Crystal Structure of a New Mononuclear Cadmium（Ⅱ） Cryptate Derived from the Condensation of Tri（2-aminoethyl）amine with Glyoxal

1 INTRODUCTION In recent years many efforts have been devoted to the preparation and characterization of pendant- arm macrocyclic complexes due to the fact that the ligating groups attached to the macrocyclic skeleton can offer additional donor groups to maintain the coordination sphere of metals in the macrocycles[1～7]. In this way, functionalized pendant arm macrocyc- lic complexes have been designed and prepared so as to mimic the structures and properties of certain metalloenzymes and…     

Metal-free reduction of tertiary phosphine oxides with Hantzsch ester简

The （COCl）2/Hantzsch ester is found to be an effective system for the metal-free reduction of tertiary phosphine oxides. The reaction proceeds under mild conditions, and is applicable to triarylphosphine oxides and alkyldiarylphosphine oxides to produce the corresponding tertiary phosphines in good to excellent yields. This new finding provides a practical, convenient and metal-free method for the reduction of tertiary phosphine oxides to tertiary phosphines, and shows potential application in organic synthesis.     

Polypeptide Brushes Grown via Surface-initiated Ring-opening Polymerization of α-Amino Acid N-Carboxyanhydrides

Polypeptide brushes are attractive platforms to generate functional and responsive interfaces that are of potential interest due to their possible biodegradability, biocompatibility and tunable secondary structures. Surface-initiated ringopening polymerization(SI-ROP) of α-amino acid N-carboxyanhydrides represents a powerful and versatile strategy to generate polypeptide brushes. This review is an attempt to capture the state-of-the-art in this field and highlights the latest developments in several selected areas. In addition to presenting an overview of the synthetic methods that have been used to generate polypeptide brushes via SI-ROP, this article will discuss the preparation of patterned polypeptide brushes, the conformational properties of surface-tethered polypeptides, ways to control chain orientation at surfaces as well as properties and applications of these thin polymer films.     

Correlation of SiO x layer thickness and properties of BOPP/SiO x composite films with spin coating process parameters

The effects of the spin coating process parameters on the thickness of the SiOx layer of the BOPP/SiOx composite film were investigated. When the concentration of tetraethoxysilane (TEOS) increased from 12.5 vol% to 55% vol%, the SiOx thickness increased from about 80 nm to 470 nm. In the sol time range of 1.5 h to 5 h the SiOx layer thickness reached a maximum at about 4 h and the change of the thickness roughly matched the change of the silica colloidal sphere sizes in sol. When the spin-coating speed of the dispensing stage increased from 450 r/min to 500 r/min, the SiOx layer thickness drastically decreased from about 1.67 μm to 400 nm. While the spin-coating speed of the thinning and drying stage went up to 1200 r/min, the SiOx layer thickness was in the range of 330 nm to 390 nm. It was also found that the SiOx layer thickness was almost increased linearly from about 500 nm to 1.02 μm with the ratio of the commercial silica colloidal to the TEOS from 0.2 to 1.0. The water contact angles decreased to about 23.0° for the BOPP/Si-Sol composite film with 1.67 μm SiOx layer and about 4.0° for the BOPP/mixing Si-Sol composite film with 1.02 μm SiOx layer. Compared to BOPP, the light transparency of the BOPP/Si-Sol composite films decreased by about 5.5% with the SiOx layer from about 80 nm to 1.67 μm and by 7.0% for the BOPP/mixing Si-Sol composite film with the SiOx layer from about 350 nm to 1.02 μm respectively.     

Topography guiding the accelerated and persistently directional cell migration induced by vaccinia virus

The rapid transmission of vaccinia virus(VACV)in vivo is thought to be closely related to the cell migration induced by it.Cell migration involved in dynamic changes of cell-substrate adhesion and actin cytoskeleton organization,which can influence by the micro/nano-scale topographic structures that cells are naturally exposed to via contact guidance.However,migration behaviors of VACV-infected cells exposed to topographic cues are still unknown.Herein,we designed an open chip with microgrooved poly(dimethyl siloxane)(PDMS)substrate to explore the topography roles in VACV-induced cell migration.Differed from the random cell migration observed in traditional scratch assay on planar substrate,VACV-infected cells had a tendency to persistently migrate along the axis parallel to microgroove with increased velocity.Moreover,infected cells exhibited a dominant elongated protrusion aligned to the micro-grating axis compare to the shorter lamella extended in any direction on smooth substrate.Interestingly,the Golgi complex preferred to relocate behind the nucleus confined within the micro-grating axis in majority of infected migratory cells.The directional polarization of cells embodied in protrusion formation and Golgi reorientation was responsible for the directionally persistent migration behaviors induced by VACV on microgrooved substrate.Infected cells response to substrate topography,causing the actin-filled stretched protrusion containing numerous virions and accelerated movement is likely to facilitate direct and rapid spread of VACV.This work opens a window for us to understand the migration behaviors of infected cells in vivo,and also provides a cue for revealing the relationship between virus-induced cell migration and virus rapid spread.     

POLYMER—SUPPORTED RHODIUM CATALYSTS FOR CARBONYLATION OF METHYL ACETATE TO ACETIC ANHYDRIDE

Two kinds of rhodium catalysts supported on cross-linked styrene-divinylbenzene copolymers containing bipyridine or o-phenylene diamine have been prepared and found to display high activity for methyl acetate carbonylation to form acetic anhydride,the activities are even higher than their homogeneous counterparts. XPS analysis was used to characterize the synthetic catalysts.The apparent activation parameters were determined to be Eα=73.3KJ/mol,ΔH^≠=66.3KJ/mol,ΔS^≠=-28.6eu.These parameters are very close to those in methanol carbonylation and imply to have analogous mechanism in both cases.     

Study on Nucleophilic Additions to endo-tricyclo[5.2.1.0~(2,6)]deca-2(6),8-dien-3-one and an Unusual Payne Rearrangement of α,β-Epoxy Tricyclodecenone

The facial selectivity of nucelophilic additions to endo-tricyclo [5.2.1.02,6] deca-2(6),8-dien-3-one 1 demonstrates a high preference for exo-facial attack to the enone moiety1. We were interested in whether it would be possible to accomplish three-ring annulation to tricyclodecenone 1 by cyclopropanation or epoxidation. Three-ring annulation would lead to an increase in total ring strain as compared with the starting enone, not as previous nucleophilic addition reactions which release strain…     

In-situ Reduction Synthesis of Bi/BiOI Heterostructure Films with High Photoelectrochemical Activity

The Bi/BiOI heterostructure films grew perpendicular to the FTO substrates were synthesized in-situ tlirough an electrochemical deposition and hydrogen reduction metliod. The metallic Bi nanoparticles were decorated onto the surface of BiOI nanosheets via an in-situ reduction, induced 6.3 times improvement of photocurrent density, compared to the pristine BiOI at 1.23 V vs. reversible hydrogen electrode(RHE).The enhancement of photoelectrochemical perfomiance was attributed not only to the efficient separation of charge resulted from surface plasmon resonance efleet, but also to the fast charge transfer at the interface due to the in-situ reduction of the films. This work provided a simple and facile strategy to in-situ construct heterostnicture films, and showed an effective metliod to improve the photoelectrochemical activity of Bi-based semiconductors.     

WO3/ZrO2 Strong Acid as a Catalyst for the Decomposition of Chlorofluorocarbon (CFC-12)

IntroductionChlorofluorocarbons(CFCs) diffusing to the stratosphere isa major reason forozone de-pletion[1 ] .Also CFCshasbeen claimed to be notoriousforitsgreenhouseeffect[2 ] .So,recent-ly it has become very important to eliminate CFCs as far as protecting the ozone layer sur-rounding the earth is concerned.Among various kinds of approaches to do destruction toCFCs,the catalytic decomposition seems to be the most practical and energetically favorableone,especially for treating small amo…     

Journal of Natural Gas Chemistry thanks the authors of our most cited articles

According to the Thomson Reuter report on 20 June 2013,the 2012 Impact Factor of Journal of Natural Gas Chemistry,renamed as Journal of Energy Chemistry in 2013,is 1.405,which ranks first among chemistry journals in China.We would like to express our appreciation to all the authors who have contributed their good work to the Journal.The following is the list of the articles published in 2010 and 2011which received the most citations and thus contributed the most to the new impact factor.     

Surfactant-assisted fabrication of graphene frameworks endowing epoxy composites with superior thermal conductivity

With the rapid growth in electronic device performance,there has been an increasing demand for thermally conductive polymer composites to handle the thermal management issue,thus contributing to the great importance to develop the graphene framework,which is evaluated as the most promising reinforcements for enhancing the thermal conductivity of polymer.Vacuum filtration is a common method to fabricate graphene framework,whereas,it is available to prepare a framework with centimeter-scale thickness by filtrating the graphene-water dispersion,due to the fact of sample cracking caused by the mismatch of surface tension between graphene and water.In this work,a surfactantassisted strategy was proposed by adjusting the surface tension of the water close to that of graphene first,then performing a conventional filtration process,to fabricate graphene framework.As a result,a thick graphene framework(thickness:3 cm)was successfully prepared,and after embedding into epoxy,the framework endows the composite(13.6 wt%)with a high in-plane thermal conductivities of12.4 W/mK,which is equivalent to≈64 times higher than that of neat epoxy.Our method is simple and compatible with the conventional filtration process,suggesting great potential for the mass-production of graphene framework to meet the practical application requirements.