Table of Content

10 October 2011, Volume 32 Issue 10

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Contents

Cover and Content of Chemical Journal of Chinese Universities Vol.32 No.10(2011)

2011, 32(10):  1. 

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Review

Research Progress of Nacre and Biomimetic Synthesis of Nacre-like Materials

SUN Na, WU Jun-Tao*, JIANG Lei*

2011, 32(10):  2231-2239. 

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Biomimetic design principles provide new methods and approaches to create new materials. Learning from nature will give us important inspiration to develop new methods to construct artificial advanced materials. Nacre is a kind of natural organic / inorganic hybrid hierarchical biological composite material. Its unique "bricks - mortar" assembly structure in a hierarchical fashion gives it extraordinary mechanical properties. Inspired by the nacre, many domestic and foreign research groups have synthesized a series of nacre-like or related composites using different methods, which have great potential application in the fields of aeronautics and astronautics, military, civil engineering and machinery etc. This paper reviews the structure and the toughening mechanisms of nacre, the imitation of nacre-like materials of different preparation methods in recent years, and some opinions and ideas are put forward.



Letter

Direct Synthesis of H2O2 Using Methane-oxygen Plasma

ZHOU Jun-Cheng*, YIN Yan-Hua, ZHENG Han-Yong, ZHOU Xu, XU Yue, GONG Jun-Song, ZHANG Long-Long, SONG Guang-Tao

2011, 32(10):  2240-2242. 

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A non-thermal atmospheric pressure plasma by dielectric barrier discharge was used to study the direct oxidation of methane to hydrogen peroxide. The effects of the structure of plasma reactors, as well as the ratio of CH4 to O2, were investigated. It is observed that, at room temperature and atmospheric pressure, methane and oxygen can be directly converted into hydrogen peroxide with high yield. When a double dielectric barrier discharge (DDBD) plasma reactor is fed with a CH4/O2 mixture containing 50 vol% at a total flow rate of 50ml min-1 (CH4+O2), it generates H2O2 with 29.2% yield and the H2O2 formation efficiency is estimated to be 221.6 g per m3 CH4/O2 mixture. The high H2O2 yield obtained by CH4/O2 plasma method may be attributed to the nonequilibrium property of non-thermal plasma that the electron energy inside the conductive filament corresponds to a few eV, while the gas temperature stays close the temperature of the background gas. As a result, the energetic electrons in the plasma region collide with molecules and atoms of the CH4/O2 mixture and generate excited species, atoms, as well as other molecular fragments that initiate the ensuing chemical reactions and produce H2O2, while the thermal decomposition of H2O2 is neglectable because of low gas temperature.



Synthesis of New pH-responsive Glycopolymers by Atom Transfer Radical Polymerization

LI Fan, PEI DanFeng, SHI Tong-Fei*, ZHANG Guo*

2011, 32(10):  2243-2245. 

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New pH-responsive glycopolymers has been designed and successfully synthesized by atom transfer radical polymerization. The architectures of the glycopolymers were confirmed by 1H-NMR and GPC. DLS and DSA tests were also performed to investigate the solution properties of the glycopolymer. This new glycopolymer contains a polyelectrolyte block and exhibits tunable pH-responsibility in water.



Preface

Synthesis of Organosilyl-substituted Aluminophosphate Molecular Sieves VPI-5

LIU Zhi, LI Yang-Xue, LIU Yun-Ling, HUO Qi-Sheng*

2011, 32(10):  2246-2249. 

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Using 1,2-bis(triethoxysilyl)ethane(BTESE), 1,2-bis(triethoxysilyl)ethylene(BTESEE), and phenyltriethoxysilane(PTES)   as silicon sources, organosilica functionalized Si-VPI-5 molecular sieves were synthesized under hydrothermal conditions and the effects of reaction conditions were investigated. Structural characterizations show that the Si atoms with organic groups are introduced into the molecular sieve frameworks. The introduction of organic groups increases the hydrophobicity of the molecular sieves, and the introduction of different organic groups leads to different increase degrees of the hydrophobicity  on the  molecular sieves.



Preparation and Characterization of X-type Zeolite Membrane Supported by Stainless Steel Net

WANG Zheng-Yang, YIN Xiao-Ju, YUE Nai-Lin, SUN Fu-Xing, ZHU Guang-Shan*

2011, 32(10):  2250-2255. 

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The synthesis of X-type zeolite membrane was studied in the hydrothermal conditions. A secondary growth method with the pre-seed step was used by choosing the stainless steel net as the support. Different reaction conditions were adjusted for the preparation of X-type zeolite membrane, such as the quantity of water, alkalinity, Si/Al ratio and the reaction time. Scanning electron microscopy technique was employed to observe the morphology of X-type zeolite membranes. Finally, the best synthesis conditions were found after the comparison and analysis of these results, better morphology without obvious defects X-type zeolite membranes were then synthesized.



Surface Modified Organic-inorganic Hybrid Microporous Silica Membranes for Hydrogen Separation

DUAN Xiao-Yong, WEI Qi*, HE Jun, YAN Jian-Ping, LI Qun-Yan, NIE Zuo-Ren

2011, 32(10):  2256-2261. 

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Organic-inorganic hybrid silica membranes were prepared by sol-gel method with bridged silsesquioxane[1,2-bis(triethoxysilyl)ethane, BTESE] and phenyltriethoxysilane(PTES) as precursors. The pore structure and hydrophobic property of the hybrid silica membranes were characterized by N2 adsorption, contact angle meter, TG and FTIR. The hydrogen permeation and separation performance was also investigated. The results show that the modified hybrid silica membranes possess a desirable microporous structure with a pore width centered at 0.4—0.6 nm. Such a pore structure can be retained after aging for 30 d  under a temperature of 40 ℃ and a relative humidity of 70%—80%.  The hybrid silica membranes become hydrophobic after modification, with a water contact angle of (125±0.4)°  at a PTES/BTESE molar ratio of 0.6. The transportation of hydrogen in the hybrid silica membranes complies with the activated diffusion mechanism, with a permeance of 8.71×10-7mol·m-2·Pa-1·s-1 and a H2/CO2 permselectivity of 5.53.



Electrospinning Fabrication and Photocatalytic Properties of LaCrO4 and LaCrO3 Nanobelts

SUN Xia, DONG Xiang-Ting*, WANG Jin-Xian, LIU Gui-Xia

2011, 32(10):  2262-2267. 

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PVP/[La(NO3)3-Cr(NO3)3] composite nanobelts were fabricated via the combination of sol-gel method with electrospinning.  LaCrO4 nanobelts and LaCrO3 nanobelts were obtained by calcination of the relevant composite nanobelts at different temperature for 8 h.  The samples were characterized by thermogravimetric-differential thermal analysis(TG-DTA),  X-ray diffractometry(XRD),  scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS).  It was found that the surface of the composite nanobelts was smooth,  and the width and thickness were (9.1±1.9) μm and 385 nm,  respectively.  Monoclinic monazite LaCrO4 nanobelts were prepared when the composite nanobelts were calcined at 600  ℃.  The width of LaCrO4 nanobelts was (2.5±0.5) μm,  and the thickness was ca. 100 nm.  Orthorhombic LaCrO3 porous nanobelts with space group Pbnm were formed by calcination of PVP/[La(NO3)3-Cr(NO3)3] composite nanobelts at 650—800  ℃.  The width and thickness of LaCrO3 nanobelts obtained by calcination of composite nanobelts at 650  ℃ were (2.4±0.5) μm and 90 nm,  respectively.  Some of LaCrO3 nanobelts was broken into LaCrO.3 nanoparticles at 800  ℃.  The width of LaCrO3 nanobelts was (1.3±0.4) μm,  and the thickness was about 90 nm,  while the mean diameter of LaCrO3 nanoparticles was ca. 80 nm.  The photocatalytic activities of LaCrO4 nanobelts and LaCrO3 nanobelts were studied using rhodamine B as degradation agent.  In the presence of LaCrO3 nanobelts obtained at 800  ℃,  the best degradation result of rhodamine B was achieved by illumination of ultraviolet ray,  and the degradation rate of rhodamine B reached  94.6% after the reactive mixture was illuminated for 200 min.



Preparation of Three-dimensionally Ordered Macroporous Spinel Li1.6Mn1.6O4 and Adsorption Characteristics of Lithium Ion-sieve

LU Hong-Yan, YANG Li-Xin*, WU Sai-Xiang, ZHANG Ling-Jun, ZHOU Li, LIU Xiao-Li

2011, 32(10):  2268-2273. 

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Three-dimensionally ordered macroporous spinel lithium manganese oxide Li1.6Mn1.6O4 was fabricated directly by polymethyl methacrylate colloidal crystal template filled with the LiNO3,  Mn(Ac)2•4H2O and citric acid mixed solution and oxidation roasting in the air atmosphere.  After the precursor was delithiated by 0.1 mol/L hydrochloric acid, three-dimensionally ordered macroporous lithium ion-sieve was obtained,  whose macroporous diameter and pore wall thickness were about 240 and 50 nm,  respectively.  The X-ray diffraction results show that Li1.6Mn1.6O4,  lithium ion-sieve and the lithium-adsorbed samples all keep spinel structure. The three-dimensionally ordered macroporous(3DOM) materials present the channel space connecting each other,  which shortens the adsorption equilibrium time of Li+. The delithiation rate of precursor gets 95% at 80 ℃, while the solution loss rates of manganese are less than 2.5% below 60 ℃.  Solution temperature has great influence on the exchange ability of Li+, raising temperature leads to the increase of Li+ and H+ reversible exchange degree, the Li+ maximum adsorption capacity is 56.7 mg/g, but the hydrogens  in the manganese 16d octahedral defect position are difficult to be exchanged. The analyses of pH titration and distribution coefficient Kd indicate that the solid acid has a high selectivity of Li+ in the coexisting solution of Li+, Na+ and K+.



Detection of E. coli O157∶H7 by Fluorescent Silica Nanoparticles and SYBR Green Ⅰ Based Two\|color Microscopic Imaging Technique

ZHOU Li-Xia, HE Ding-Geng, HE Xiao-Xiao*, SHI Hui, WANG Ke-Min*, CAO Jie

2011, 32(10):  2274-2279. 

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A novel two-color immunofluorescent microscopic imaging technique for the rapid and sensitive detection of E. coli O157∶H7 was developed by fluorescent silica nanoparticles and SYBR Green Ⅰ. Based on antigen-antibody interaction, the anti-E. coli O157∶H7 antibody conjugated RuBpy-doped silica nanoparticles were used to recognize E. coli O157∶H7 specifically. The bacteria sample was then stained with a nucleic acid dye SYBR Green I and imaged with confocal microscope. The separation-free detection of E. coli O157∶H7 was successfully carried out in buffer and bacterial mixture, respectively. The whole detection process could be finished within 3 h, and the detection limit for E. coli O157∶H7 was 2.6×103Cell/mL. Considering the antibodies for various bacteria, this proposed method might be promising for rapid and sensitive detection of other bacteria.



Metabolic Profiles of Nonylphenol in Rat Urine

WANG Wei-Hua, LIU Chun-Hong, SUN Yuan-Ming*, LIN Feng*, ZHANG Ming-Ming, WANG Zhao-Bin, ZHANG Min-Yi

2011, 32(10):  2280-2285. 

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The metabonomics method was applied to investigate the effects of nonylphenol(NP) on urine metabolism in Sprague Dawley rat. The profiles of urine samples were obtained with high performance liquid chromatography coupled with time-of-flight mass spectrometry(HPLC/TOF-MS). The data were analyzed with the principle components analysis(PCA) to distinguish the differences of profiles between the NP groups and the control group. The potential biomarkers and effective biomarkers were screened out according to the t-test, and identified with Metlin Scripps Center for mass spectrometry database. The results indicated that the contents of phenyl glucuronide, homocystein, 3-nitropropionic acid, creatinine and 5-hydroxytryptamine changed obviously in urine after exposure to NP, which constituted the metabolic profiles in rat urine of NP, and might injury reproductive system, immune system, nervous system and lipometabolism in metabolism process. This study provides the basis for toxicology studies on NP to organisms from the standpoint of metabolism.



Simutaneous Determination of 17 Components in Oxidative Hair Dyes by Gas Chromatography-Mass Spectrometry

LAI Ying*, CHEN He-Xiu, LIN Rui, WANG Hong-Hui, DONG Qing-Mu, HUANG Zong-Ping

2011, 32(10):  2286-2292. 

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A reliable Gas Chromatography-Mass Spectrometry(GC-MS) method was developed for the simultaneous determination of 17 dye intermediates, including benzenediamines, aminophenols, benzenediols, naphthalenediol and diaminopyridine, in oxidative hair dyes. Samples were extracted with 50% ethanol by adding sodium dithionite to prevent oxidation. A DB-WAX capillary column was selected for the separation of both water soluble and alcohol soluble hair dye intermediates. The results showed that 17 dye intermediates were well separated within 25 min. The detection limits of these compounds were in the range of 2-380 mg/kg. The recoveries of the target compounds in hair dyes ranged from 81.1% to 103.7% with four addition levels. The method described was validated by 5 different laboratories and successfully applied to the analysis of commercial oxidative hair dyes.



Electrochemistry and Electrocatalysis of Hemoglobin with SiO2 Gel Film Layer-by-layer Assembled on Carbon Nanotubes-Au Nanoparticles Modified Electrode

XU Ying, ZHANG Xiao-Yan, YANG Jing*, HE Pin-Gang*, FANG Yu-Zhi

2011, 32(10):  2293-2300. 

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Protein direct electrochemistry study and its electro\|catalysis analysis were introduced,  involving layer-by-layer alternate assembly of hemoglobin(Hb)and SiO2 gel film onto electrode surface. The electrode was firstly modified with the nano-compound of multi-walled carbon nanotubes and Au nanoparticles, i.e., MWNTs-Au/GC electrode. Then Hb and SiO2 gel film were alternately spread onto the electrode surface to stabilize the protein and its amount and bioactivity, thus resulting {SiO2/Hb}n/MWNTs-Au/GC electrode. Under the optimized n=2, the Hb on the {SiO2/Hb}2/MWNTs-Au/GC electrode displayed its intrinsic bioactivity well, transferring electrodes with electrode and catalyzing H2O2 reduction as one peroxidaze enzyme.



Synthesis and Properties of Novel Photochromic Dyads Based on Spiropyrans and Schiff Base

YIN De-Fei, CHENG Hong-Bo, HUO Xiao-Lian, LI Hai-Ning, PANG Mei-Li*

2011, 32(10):  2301-2305. 

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A series of novel photochromic compounds(4a—4n) based on spiropyrans and Schiff base were synthesized.  Their structures were characterized by 1H NMR, IR, and HRMS.  The compounds were proved by UV measurement to have excellent photochromic properties both in organic solutions and in PMMA polymer films. The thermal decay process of the representative compound 4a in methanol, and  compounds   4a, 4f in  PMMA polymer films  were also studied.  The color of compound 4e differed  from other compounds.  Its   merocyanine  form exhibited rare green color. The representative compound 4a show good fluorescence properties in dichloromethane solution.  The results showed that the novel photochromic compounds based on spiropyrans and Schiff base have excellent photochromic properties in methanol, dichloromethane, cyclohexane solution, and PMMA polymer films.  These properties are great helpful for their potential application in the field of multi-function material.



Studies of 1-Acetyl-3-(2-hydroxyl-4,6-dimethoxylphenyl)- 5-aryl-2-pyrazoline as Fluorescent Sensors for Cu2+

YANG An-Bo, WU Jing, XU Zhu-Xiong, WANG Bing-Xiang*

2011, 32(10):  2306-2310. 

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Copper plays an important role in various physiologic processes. The design and synthesis of chemosensors for copper ions has become a very active area of research. The synthetic Cu2+ selective fluoroionophores so far reported suffer from low sensitivity and, in general, higher concentrations of interfering metal ions disturb the selectivity towards Cu2+. We report here the synthesis of six 1-acetyl-3-(2-hydroxyl-4,6-dimethoxylphenyl)-5-aryl-2-pyrazoline (4) and the studies of them as fluorescent sensors for Cu2+ ion. The structures of all the products were determined by IR, MS, 1H NMR and elemental analysis. Their UV and fluorescence spectra were measured. The influences of eight metal ions such as Cu2+, Zn2+, Ni2+, Co2+, Na+, Al3+, Cd2+, Ca2+, Mn2+on their fluorescence properties were studied. Spectroscopic studies revealed that the compounds 4a～4f had rather strong affinity toward Cu2+, The specificity of the probes 4f toward Cu2+ were determined. Nearly no fluorescence intensity changes were observed in emission spectra with Zn2+, Ni2+, Co2+, Na+, Al3+, Cd2+, Ca2+, Mn2+. However, under identical conditions, the studies were showed fluorescence quenching with Cu2+. So we have developed an new fluorescent sensor 4f. It showed high sensitivity and selectivity toward Cu2+ in DMSO.



Articles

Synthesis and Catalytic Application of Co(Ⅱ)-3,8-diethyl Deuteroporphyrin Dimethyl Ester to the Oxidation of Cyclohexane

CUI Qiao-Li, XU Shi-Chao, SUN Cheng-Guo, HU Bing-Cheng*

2011, 32(10):  2311-2315. 

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The oxidation of alkane, alkene and carbonyl catalyzed by metallo-deuteroporphyrin derivatives were reviewed. Because of their closer relationship to monooxygenase P-450, metallo-deuteroporphyrin derivatives have higher catalytic activities than other metallo\|porphyrin derivates. The Co(Ⅱ)-3,8-diethyl deuteroporphyrin dimethyl ester was prepared from hemin by a four-steps reaction including demetalation, esterification, hydrogenation and complex reactions. Without the additional of organic solven and any coreductant, Co(Ⅱ)-3,8-diethyl deuteroporphyrin dimethyl ester was used as catalyst for cyclohexane oxidation using air as oxidant. The catalytic mechanism of this reaction was preliminary studied by UV-Vis spectra. The results indicated that the Co(Ⅱ)-3,8-diethyl deuteroporphyrin dimethyl ester which overcame the shortage of instabili\| ties of 3,8-divinyl of cobalt(Ⅱ) protoporphyrin IX dimethyl ester had satisfying catalytic activity in the oxidation of cyclohexane and the total yield of cyclohexanol and cyclohexanone was 16.9%.



Synthesis and Properties of Two Photochromic Diarylethenes Containing 1,3,4-Oxadiazoles

ZHAI Shu-Rong, ZHU Xue-Feng, ZENG He-Ping*

2011, 32(10):  2316-2320. 

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Two novel photochromic dithienylethenes compounds, (E)-3-(5-phenyl-1,3,4-oxadiazol-2-yl)-2,3-bis(2,4,5-trimethylthiophen-3-yl)acrylonitrile(3) and (Z)-3-[5-(4-{5-[(E)-2-cyano-1,2-bis(2,4,5-trimethylthiophen-3-yl)vinyl]-1,3,4-oxadiazol-2-yl}phenyl)-1,3,4-oxadiazol-2-yl]-2,3-bis(2,4,5-trimethylthiophen-3-yl)acrylonitrile(4) containing 1,3,4-oxadiazoles, were synthesized. Their structures were confirmed by IR, NMR, MS and elemental analysis.  Moreover, their UV-Vis absorption properties, fluorescent properties, photochromic dynamics character and fatigue resistance were studied.  The results indicated that they processed good photochromic behavior, and their cyclization and cycloreversion reactions were zeroth and first order reaction, respectively.



Preface

Selective Oxidation of Sulfides with Hydrogen Peroxide Catalyzed by Supported Ionic Liquid Brush / Peroxophosphotungstate

SHI Xian-Ying, MA Wen-Juan, HAN Xiao-Yan, ZHANG Wen, Lü Ai-Feng, WEI Jun-Fa*

2011, 32(10):  2321-2326. 

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A heterogeneous catalyst composed of peroxotungstates immobilized on bis-layered ionic liquid brush-modified silica has been synthesized and characterized by elemental analysis, IR and SEM-EDAX. The catalytic property of the system was examined for the oxidation of sulfides to sulfoxides or sulfones with 30% hydrogen peroxide at room temperature. The results showed that this recoverable catalyst exhibited both high catalytic activity and excellent selectivity. The sulfides were selectively oxidized to sulfoxides with traces of sulfones using 1.1 times of H2O2. Changing the amount of H2O2 to 2.5 times, sulfones were given as the main products. It is noteworthy that the catalyst afforded high chemoselectivity towards sulfur groups with unsaturated double bonds even though excess hydrogen peroxide was used. There was no apparent loss of catalytic efficiency through seven cycles.



Synthesis and Properties of Two Novel Azobenzene Chromophores

WANG Yang, TANG Xian-Zhong*, TANG Xiang, WANG Yun-Long, ZHAO Shuai

2011, 32(10):  2327-2330. 

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Organic second-order nonlinear optical(NLO) materials have been intensively studied over the past two decades for their potential applications in photonic and electro-optic devices.  In order to exhibit second-order NLO properties, these materials must have push-pull structrue containing both electron-acceptor and electron-donor groups connected by an electron-transmitting bridge.  In this paper, two novel organic NLO chromophores MFNC and EFNC were designed with tricyanofuran as electron acceptors, azobenzene as conjugate bridges and electron donors were dimethylamin and diethylamin. They were synthesized by azo coupling reaction and aldol condensation reaction, and were characterized by FTIR, 1H NMR and elemental analysis, respectively. TGA and DSC results revealed that the Td of EFNC was up to 266  ℃ and lightly better than MFNC.  By measuring the UV-Vis spectra of two materials in chloroform, acetone, DMSO separately, we got the μgβ value of EFNC with solvatochromism method led to as large as 59706×10-48 esu at 1064 nm.  Both thermal and NLO properties indicate that they have great potential in application of highly integrated optical devices.



Asymmetric Transfer  Hydrogenation of β-Amino Ketone Catalyzed by (S,S)-TsDPEN-Ru Complex and Its Application in the Synthesis of Duloxetine

ZHAO Jin-Feng, DOU Hai-Jian, ZHOU Yu-Han, QU Jing-Ping*

2011, 32(10):  2331-2334. 

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(S)-γ-aminoalcohol is a key intermediate for the preparation of Duloxetine. In this paper, we describe an effective method to obtain (S)-γ-aminoalcohol through asymmetric transfer hydrogenation with an easy accessible (S,S)-TsDPEN-Ru complex as catalyst in HCOOH/Et3N system. A variety of β-amino ketones were examined. β-Amino ketones with donating groups(3a~3c) decomposed to give 1-(2-thienyl)-1-propanone during the reaction. On the other hand, (S)-γ-aminoalcohols with withdrawing groups(4e,4f) were obtained in high e.e. values(>95% e.e.) and good yields under optimal reaction conditions. This novel procedure was applied in the asymmetric total synthesis of Duloxetine as a key step. Starting from acetyl thiophene, Duloxetine was obtained in 69% yield and 91.7% e.e..



Synthesis, Crystal Structure and Herbicidal Activity of Aurone Derivatives

LIU Bin, ZHANG Min, XIE Long-Guan, LI Yong-Hong, XU Xiao-Hua*

2011, 32(10):  2335-2340. 

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Pesticides based on natural products are attracting more and more attentions. They are low-toxic, readily degradable and low drug-resistant. This is an important field for developing new pesticides. Previous effords were mainly focused on developing new insecticides and bactericides. So there are few commercial herbicides originated from natural products. Aurones are natual product existing in fruits and flowers of certain plants. It was found that some of them showed certain herbicidal activity. Herein, seventeen aurones derivatives were synthesized. X-ray single crystal diffraction showed that the conformation of its double bond was Z. And these compounds were assayed for their inhibiting activity against Echinochloa crusgalli and B rassica cam pestris. Results indicated that they displayed modest inhabitation toward B rassica cam pestris, but bad toward Echinochloa crusgalli. Under 100 μg/mL, inhibiting rate of compoud 15 on B rassica cam pestris was up to 88.5%, and it reached to 81.3% given by subsequent rescreening at 10 μg/mL. Electronic property on ring A and LogP value of the whole molecular play a important role in maintainning its activiy. Compound 15 is a good leading structure for further optimization.



Influence of Electronic Effects of 3,5-Polyoxo-stilbene Substrates in the Fructose-derived Chiral Ketone System

ZHANG Cheng-Lu*, SHAO Yi, ZOU Li-Wei, ZHOU Long, XU De-Qing, GAO Li-Na, QU Rui-Feng

2011, 32(10):  2341-2348. 

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The electronic effect of catalysis and substrates plays an important role in the enantioselectivity of asymmetric catalytic reactions. The stilbenes, especially resveratrol which have a large conjugated system, have satisfactory bioactivities and can take place many reactions. Thus it is valuable to study the structure modification and structure activity relationship. Ten  stilbenes were designed based on the structure of resveratrol, and synthesized through Wittig-Horner reaction in the work. The electron cloud distribution was regulated through changing the type and the position of the substances on benzene ring. The optimized configuration was obtained through calculation under FH/3-21g level.  And the rational mechanism was put forward.  The electronic effect of the substances on the selectivity of catalytic reaction was studied.  In the system, frucase-derived chiral ketone was used to study either the asymmetric epoxidation or oxidation reaction.  As a result, the applied scope of the chiral ketone was determined, the reaction position in the big conjugated system was found when polyoxo-substances exist, the rational analysis of the electronic effect of the substrates was also put forward.



Template Directed Selective Deposition of Organic Luminescent Molecules

LIN Li, WEI Shi-Gang, LI Hui, HAO Juan-Yuan, Lü Nan*

2011, 32(10):  2349-2352. 

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Micro- and nano-scale fluorescent patterns over large area were fabricated by template directed selective deposition of organic luminescent molecules. The template was fabricated by combination of Nanoimprint Lithography(NIL) and metal evaporation and the following “lift-off” process. In the template, the organic molecules have larger binding energies on the patterned area in comparison to the substrate, so the site-selective deposition of organic molecules can be obtained by choosing proper template. It is a fast means to fabricate large-area fluorescent pattern, which provides the possibility to increase the extraction efficiency of organic light emitting diodes(OLEDs).



Catalysis of Water-soluble Porphyrins for Oxidation of 1,5-Dihydroxynaphthalene

HOU Zong-Sheng, REN Qi-Zhi*, WANG Ying, ZHANG Hong

2011, 32(10):  2353-2359. 

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A series of water-soluble free base porphyrins(H2TPPS, H2TCPP and H2TMPyP) and their metal complexes(FeTPPS, ZnTPPS, CoTPPS) were efficiently synthesized and characterized. As photosensitizers, these porphyrins were used to catalyze the oxidation of 1,5-dihydroxynaphthalene under visible light irradiation. The main product were identified as 1,5-dihydroxynaphthalene. The catalytic process was monitored by UV-Vis method and the optical catalytic conditions were established. The water phase system and water-dichloromethane double phase system were explored. The effects of various factors such as substituent groups, central metal ions were investigated. The catalytic results show that anionic porphyrins have efficient catalytic activity; At the beginning of the reaction, high catalytic acitivity can be obtained for iron porphyrin, while it decreases greatly because of catalyst photolysis; The sodium sulfonic porphyrin is the most stable catalyst in the reaction system and has the best catalytic activity.



Effects of Doping La, Mn on the Properties of CeO2-ZrO2-Al2O3

ZHANG Xue-Qiao, XIN Xin, LIU Jian-Ying, LIU Sheng-Yu, ZHAO Ming*, CHEN Yao-Qiang*

2011, 32(10):  2360-2366. 

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A series of materials CeO2-ZrO2-A12O3(CZA) were prepared by the co-precipitation method and characterized by specific surface area measurements (BET), X-ray diffraction (XRD), H2-temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectroscopy (XPS). The results showed that these successfully-prepared CZA solid solutions had an optimum textural performance after calcinations at 600℃ for 3h and the support sample of doping La and Mn together still possessed the high thermal stability. According to the H2-TPR, the modified sample by La and Mn showed a best property of reducibility in low temperature. XPS results indicated that by doping La, the transfer of Mn from the bulk to the surface in calcinations was restrained and the concentration of adsorbed oxygen was retained．



Influence of B on the Structures and Electrochemical Properties of Sn-Co Alloy

SHEN Ding, YANG Shao-Bin*, WU Xiao-Guang, MI Han

2011, 32(10):  2367-2370. 

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The Sn-Co/B composites were synthesized using solid\|state sintering and the influence of B element on the structures and electrochemical properties was analyzed. XRD results illustrate that Sn-Co alloy consists of CoSn phase. Adding B results in the refinement of grain size and the formation of CoSn2 phase. Constant-current cyclic testing show that adding B improves the cycle performance of Sn-Co alloy, but reduce its discharge capacity. The initial discharge capacity of Sn-Co/B(4%, mass fraction) is 216 mA•h/g and the capacity retention is 82.9% after 30 cycles, showing the composite has good structural stability.



Electrochemical Impedance Spectroscopy Studies on Oxygen Reduction Reaction Catalysed by Macrocyclic  Metal Phthalocyanine Compounds

MA Jin-Fu*, LIU Yong-Ning

2011, 32(10):  2371-2375. 

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The oxygen reduction reaction(ORR) catalyzed by metal phthalocyanine macrocycles(FePc, CoPc, FeCoPc2) in alkaline solution was investigated by line sweep voltammograms(LSV) and electrochemical impedance spectroscopy(EIS). The results of these two methods have the same trend.  The characteristic of two semi-circles and an arc on the gas diffusion electrodes were presented on the EIS Nyquist plot, and the EIS curves at the potential -02 V(vs. Hg/HgO) were fitted by the equivalent circuit with analytical software Z simpwin. The result show that ORR on MPcs is an 2-electron transfer process with an intermediate product of HO-2.  The simulated kinetics data of the equivalent circuit was also analyzed.  Fitting results of equivalent circuit show that the FeCoPc2/C as ORR catalyst for reducing has higher catalytic activity because of lower Rc+Rct than that of FePc/C, CoPc/C.



Effects of Cationic and Zwitterionic Surfactants on Wetting of Quartz Surfaces

LI Zhen-Quan, WANG Zeng-Lin, ZHANG Lei, XU Zhi-Cheng, ZHANG Lu*, ZHAO Sui

2011, 32(10):  2376-2381. 

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The wetting behavior of quartz surface by aqueous solutions of cationic surfactant hexadecyl glycidyl ether ammonium chloride(C16PC) and zwitterionic surfactant hexadecyl glycidyl ether glycine betaine(C16PB) were investigated by the sessile drop analysis.  The influence of surfactant type and concentration on contact angle were expounded and the change in adhesional tension and adhesion work were discussed.  From obtained results it was appeared that an increase in quartz-water interface free emerge(γsl) due to the adsorption of both surfactants at the high-energy quartz interface.  For C16PB, its adsorption at quartz surface can occur by weak interactions, which can be expected approximately equal ability of an increase in γsl  and reduction of the surface tension of the liquid(γ1g).  As a result, there was little change of the contact angle with increasing bulk concentration.  However, in the case of C16PC, the surfactant molecules can form a monolayer with alignment structure on the quartz surface through electrostatic interaction, as the bulk concentration increases, and then the bilayer formed when the concentration is near to critical micelle concentration(cmc).  The contact angle can be divided into four regions and passed through a maximum with increasing concentration.



A Al-H2O2 semi fuel cell using Ni foam supported NiCo2O4 nanowire arrays as cathode

TIAN Yong-Mei, LEI Ting, WANG Gui-Ling*, CAO Dian-Xue

2011, 32(10):  2382-2386. 

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A Al-H2O2 semi-fuel cell using Ni foam supported NiCo2O4  nanowire arrays as cathode was reported.  Ni foam supported-NiCo2O4 nanowire arrays were prepared by a template-free growth method, and demonstrated that NiCo2O4 nanowires grow almost vertically from the surface of foamed Ni substrate by scanning electron microscopy(SEM). The effects of concentrations of H2O2, flow rate of electrolyte as well as operation temperature on the cell performance were investigated. The cell exhibited an open circuit voltage of about 1.40 V; peak power densities of 79 and 120 mW/cm2 at current densities of 98  and 172 mA/cm2 and a cell voltage of 0.80 V and 0.70 V operating at room temperature and 320 K, respectively, using aluminium sheet as anode fuel and 0.6 mol/L H2O2 as oxidant. The current density at 0.7 V and voltage 75 mA/cm2 remained nearly constant within a 5000 s  test period, the Ni foam supported NiCo2O4  nanowire arrays electrode exhibits superior activity, stability, and mass transport property for H2O2 electroreduction.



Fabrication of the Ag Dendrites for Surface-enhanced Raman Scattering

ZHAO Hong, FU Hong-Gang*, TIAN Chun-Gui, REN Zhi-Yu, YUANG Ming-Ming

2011, 32(10):  2387-2390. 

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Ag dendrites were obtained on cleaned Cu plate via a simple galvanic displacement process between AgNO3 and Cu at room temperature, using sodiun dodecylsulfate(SDS) as surfactant. By the control of the concentration of precursor(AgNO3), Ag dendrites with different density were obtained. The performance of the Ag dendrites as surface enhanced Raman scattering(SERS) active substrate was evaluated by 4-aminothiophenol(4-ATP), adenine and Rhodamine G6 as the probe molecules. Compared with Ag nano particles(AgNPs) film, the SERS signal on Ag dendrites was obviously improved than on the AgNPs film. It is concluded that the Ag dendrites on Cu plate will be powerful SERS substrate for organic molecule and biological molecular detection.



Branched Ag-TiO2 Composite Obtained by Electrospinning and Degradation of Its Application for Photocatalytic Organic Pollution

HU Song, LIU Yang, LI Jing-Hong*

2011, 32(10):  2391-2395. 

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TiO2 nanofibers were synthesized by electrospinning technique and used as the template to fabricate branched Ag-TiO2 composite.  The as-prepared Ag-TiO2 composites were characterized by X-ray diffraction and electron microscopy analysis techniques.  The photocatalytic activities of as-prepared branched Ag-TiO2 composite were measured with the degradation of active methylene blue(MB).  Results show that the as-prepared branched Ag-TiO2 composite exhibited higher photocatalytic activity in comparison with TiO2 nanofibers and commercial TiO2 P25.



Catalytic Performance Comparison of the Novel Catalyst La2CuMnO6 and LaMnO3 for Methane Combustion

CHEN Jie, HU Rui-Sheng*, HU Jia-Nan, LU Tian-Zhu

2011, 32(10):  2396-2401. 

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A novel rare-earth double perovskite-type catalyst La2CuMnO6 was prepared  by the sol-gel method using citric acid as a complex agent. The catalytic activity of the sample toward methane combustion was evaluated. The catalyst was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, magnetic properties, H2-temperature-programmed reduction, Scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that La2CuMnO6 forms a single-phase double perovskite-type oxide by the sol-gel method at 1100 ℃ under air atmosphere for 3 h. The La2CuMnO6  reveals good catalytic activity for methane combustion. It shows light off temperature T10 of 437.5 ℃ and T90 of 649.2 ℃. Compared with the single perovskite-type oxide LaMnO3 which always was made for methane combustion catalyst, the lower light-off temperature T10 decreases 53.1 ℃ and total conversion T90 decreases 116.5 ℃, respectively. The results of FTIR show that the synthesized oxides all possess perovskite-type structures. The results of H2-TPR indicate that an increasing in the oxygen mobility existe in La2CuMnO6.  Furthermore, the SEM, TEM and the magnetic properties results also testified that, the two catalysts have different surface feature and magnetic property, In addition, XPS shows that La2CuMnO6 have more oxygen vacancies than LaMnO3. These results are in the accord with methane catalytic combustion.



3D-QSAR Study and Molecular Design of Benzimidazole Derivatives as Corrosion Inhibitors

HU Song-Qing*, MI Si-Qi, JIA Xiao-Lin, GUO Ai-Ling, CHEN Sheng-Hui, ZHANG Jun, LIU Xin-Yong

2011, 32(10):  2402-2409. 

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The Three-dimensional quantitative stucture-activity relationship(3D-QSAR) of benzimidazole derivatives as corrosion inhibitors in hydrochloric acid was studied using Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices Analysis (CoMSIA) methods, and the stability and predictive ability of the 3D-QSAR model were examined by “leave- one- out” (LOO) cross- validation method. The results indicated that steric, electrostatic and hydrogen-bond donor fields were main factors to inhibition performance. CoMFA (q2=0.541，R2=0.996) and CoMSIA (q2=0.581，R2=0.987) models had better statistical stability and predictive ability. New benzimidazole molecules with excellent corrosion inhibition properties were designed by 3D-QSAR contour maps. These results suggested that it was available to introduce 3D-QSAR methods into the field of corrosion inhibitor, and the method provided a new train of thought for the research and development of corrosion inhibitor in the oil and gas field.



Dissipative Particle Dynamics Simulation of Association Reaction in Telechelic Polymers

LI Hui, ZHANG Jing, LIU Hong*, SUN Chia-Chung

2011, 32(10):  2410-2414. 

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The process of association reaction in telechelic polymer solution was investigated by dissipative particle dynamics(DPD)simulation method. We studied the effect of some master factors such as the reaction degree, the length of telechelic polymers and the concentration of telechelic polymers on the product morphology. With a further investigation, we also studied the energy of association and the number of characteristic structures in steady state. The primary factors in association reaction include the reaction degree which controls the microstructure of this system, and the length of telechelic polymers which controls the connectivity of this system, and the length of telechelic polymers which controls the connectivity of the product. Besides, we find there is a linear dependence of the number of characteristic loop chains on the concentration of telechelic polymers, as well as on the length of telechelic polymers.



QSAR and Molecular Design of Some Quinoline Derivatives as Antimicrobial

XIA Shu-Wei*, MAO Ya-Pin, XUE Qian-Qian, YU Liang-Min

2011, 32(10):  2415-2420. 

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The relationship between structures and antibacterial activities of 15 quinoline derivatives were studied by using both density functional theory (DFT) at the B3LYP/6-31G (d, p) basis set and stepwise multiple linear regression analysis (SMLR) method. The main independent factors which affected the activity of the compounds were determined by stepwise regression analysis, then a QSAR model was established. The stability and predictive ability of the model were examined by “leave-one-out”(LOO) cross-validation method. The result suggested that the nucleophilic frontier electron density of C(5) atom ( ), the bond order of C(9)-N(1) ( ) were the predominant factors affecting antibacterial activity against S. aureus. The fitting correlation coefficient (R2) and the cross-validation coefficient (q2) values were 0.814 and 0.734 respectively, showing this model with a good predictability. Based on this QSAR study, 4 new compounds with high antibacterial activity had been theoretically designed.



Multibody Dissipative Particle Dynamics Study of the Composition Effect on the Morphology of Block Copolymer Thin Film

LI Yan-Chun, LIU Hong, HUANG Xu-Ri*, SUN Chia-Chung

2011, 32(10):  2421-2426. 

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We use multibody dissipative particle dynamics method to investigate the thin film formed by self-assembly of block copolymer on attractive surface under evaporation condition. We consider the composition effect on the morphology of diblock and triblock copolymer thin film. We obtain disorder and lamellar morpho-logy and give the time evolution of the order parameter and the film thickness. The results reveal that the composition of block copolymer effects on the order parameter rather than the film thickness. If one of the compositions is shorter, it is easily to form disorder morphology with lower order parameter. On the other hand, it is easily to form lamellar morphology with higher order parameter.



Shear Effects on Crystallization Behavior of iPP/PEcO Blends

WEN Hui-Ying*, XIAO Sheng-Ling, LI Hong-Fei*, JIANG Shi-Chun, AN Li-Jia

2011, 32(10):  2427-2431. 

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Crystallization behavior of sheared iPP/PEcO blends were investigated via SAXS, WAXS and POM. The results indicate that the morphology of sphere crystal obviously changes with PEcO content in the blend. Shear not only increases the density of spherulite but also induces the formation of fiber-like crystal. The lamellar orientation and crystallite orientation have been affected by shear, especially the orientation of lamellae is more obvious than that of crystallites. The degree of lamellar orientation enhances with the increasing amount of elastomer, whereas the degree of crystallite orientation decreases with the increasing of elastomer. In situ synchrotron SAXS data shows that the long period of lamellae decreases at the early period of crystallization and afterwards remains fixed; high shear intensity decreases the induction time for crystallization and obviously accelerates the process of crystallization kinetics. The evolvement of crystalline structure and the degree of orientation differences between crystallite and lamellae of the blend crystallization under shear may support the mesomorphic phase concept of flexible polymer crystallization process proposed by Strobl. Based on all the analyses a relatively stable mesomorphic structure is thought to have formed before shear is composed and the shear-induced initial states of polymer play an important role in affecting the crystallization behaviors.



Structure Simulation, Synthesis and Properties of Fluorenyl Cardo Poly(imino ketone)s

MIAO Lu-Bin, XU Zhen, CHANG Guan-Jun, LUO Xuan, ZHANG Lin*, LIN Run-Xiong*

2011, 32(10):  2432-2436. 

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Fluorenyl cardo poly(imino ketone)s (PIKF) were designed and synthesized by reacting 1,4-bis-(4-bromobenzoyl)-benzene and 9,9-bis(3-R-4-aminophenyl)fluorene (R: H, CH3 or F). The structures of the resulting polymers were simulated by Materials Studio(MS) and characterized by FT-IR, 1H NMR spectroscopy and elemental analysis. The thermo and optical properties of PIKF were evaluated. High glass transition temperatures (Tg> 215 ℃) and decomposition temperatures (T5%> 400 ℃) were observed by DSC and TGA, respectively. The UV-vis absorption spectra of polymers exhibited two absorption peaks around 271 nm and 369 nm; The maximum emissive wavelength were 501nm in both PIKF-1 and PIKF-2, and 492nm in PIKF-3. PIKF were amorphous at room temperature. Good solubility of PIKF in ordinary organic solvents such as THF and chloroform was confirmed. These properties of the polymers were related to the cardo structure of the fluorene moiety placed on the main chain.



Preparation of Polyvinyl Alcohol Hydrogel Microspheres with High Strength

GAO Su-Zhao, CHEN Ji-Da*, QI Qian-Qian, SHU Rong-De, QIU Zhi-Ping, REN Jing-Zheng

2011, 32(10):  2437-2440. 

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Physical cross-linked polyvinyl alcohol(PVA) hydrogel microspheres with high strength were prepared by a modified high-voltage electrostatic technique. The hydrogel microspheres were solidified and suspended in coagulation liquid composed of chloroform and acetone, then the microspheres in coagulation liquid were frozen and thawed to get PVA cross\|linked. The influence factors of PVA microspheres' diameter and morphology, such as, coagulation liquid, PVA solution concentration and flow rate, temperature and humidity and electrostatic field strength of high-voltage electrostatic system, the number of froze and thaw cycle of PVA were investigated. The results showed that high-voltage electrostatic system modified with atmospheric steam to control temperature and humidity  of PVA microsphere formation area was an effective method to overcome microfilament formation while PVA solution was in higher concentration, the optimized condition for prepare PVA hydrogel microspheres with high strength and controlled diameter was coagulation liquid of chloroform/acetone(2∶1, volume ratio), frozen at -20 ℃ and thawed at room temperature for five cycles, PVA solution concentration of 12% in weight, flow rate of 2 mL/h, electrostatic field strength of 12-15 kV, electrode distance of 3 cm, and the PVA hydrogel microsphere has a widely potential use in the field of tissue engineering.



Multiphoton Pumped Green Fluorescence in a Hyperbranched Triphenylamine-oxadiazole Conjugated Polymer

QIAN Ying*, Lü Xin-Ming, ZHOU Zhi-Qiang, CUI Yi-Ping

2011, 32(10):  2441-2446. 

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A novel hyperbranched triphenylamine-oxadiazole fluorescence polymer PI was synthesized by Pd-catalyzed Heck reaction. Three-photon and two-photon upconversion fluorescence spectra of PI were measured using a femtosecond Ti:sapphire that was pumped by a femtosecond laser at the near-infrared region of 800 ~ 1350 nm. Its three-photon and two-photon absorption coefficient was determined by mearuring the nonlinear transmissivity at a known input intensity level. The three-photon excited fluorescence have been observed with the central wavelength at 525 nm in THF , at 534 nm in CH2Cl2 and at 578 nm in DMF, respectively. The maximum peaks of two-photon excited fluorescence were at 527 nm in THF , at 532 nm in CH2Cl2 and at 573 nm in DMF, respectively. Increased solvent polarity were found to induced a marked red-shift of the emission band of multiphoton pumped fluorescence in polymer PI. The hyperbranched triphenylamine-oxadiazole conjugated polymer displayed large multi-photon absorption and strong upconversion fluorescence properties.



Preparation of Melamine-formaldehyde Microspheres and Microcapsules Based on Poly(glutamic acid) by Template Method

ZHANG Ying, YAN Shi-Feng, RAO Shui-Qin, ZHENG Yan-Zhen, YIN Jing-Bo*, CHEN Xue-Si*

2011, 32(10):  2447-2452. 

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Melamine-formaldehyde (MF) microspheres were prepared by dispersion polymerization. The influences of pH value and reaction time on partical size, surface potential and solubility of MF microspheres were studied. Using MF microspheres as templates, hollow PGA/CS microcapsules were fabricated by layer-by-layer technique. The templates and microcapsules were characterized by polarization microscope, nano-granularity and potential analyzer, IR and TEM. The results show that the partical size and surface potential of MF microspheres decrease with the reducing of pH and its solubility in hydrochloric acid becomes worse as the time grows. The main driving force is electrostatic force between PGA and CS, which is supported by alternating ζ-potentials. The hollow microcapsules with uniform size and good dispersity shows successful loading of model drug rhodamine, which is expected to find application in excellent carriers of water-soluble drugs.



Effect of Composition on Physical\|chemical Properties and Biological Properties of Hydroxyapatite/Aliphatic Polyurethane Scaffolds for Bone Tissue Engineering

WANG Li, ZUO Yi*, ZOU Qin, LI Yu-Bao

2011, 32(10):  2453-2459. 

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Aliphatic polyurethane (PU) and hydroxyapatite (HA) composite scaffolds were prepared by in-situ polymerization and gas self-foaming process. The morphologies and properties of the scaffolds were studied by varying the content of HA, foaming agent (water) and soft/hard segment ratio and characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and mechanical test. The results showed that the compressive strength of the scaffolds increased with both the HA content and the hard segment content. The scaffold porous structure was affected by HA content and foaming agent. The scaffold porosity increased with HA content and decreased with the hard segment content. The average pore size of the scaffold also increased with the content of foaming agent. MTT results and SEM observation of cells showed that the porous structure of HA/PU scaffold provided a good microenvironment for cell adherence, growth and proliferation. After implantation in rat muscle, the scaffold was well tolerated by host tissues. The porous HA/PU scaffold provides a good perspective for designable tissue-engineering scaffolds.



Relationship Between Structure and Solubility of Silk Fibroin and Glycerol in Blend Film

LUO Min-Qing, LU Shen-Zhou*

2011, 32(10):  2460-2464. 

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The change of crystal structure and crystallinity of silk fibroin(SF) in the process of becoming insoluble by adding glycerol was studied. The blend silk fibroin films were casted by silk fibroin solutions mixing with glycerol at a series of ratios at room temperature. The water-content, solubility, structure, and mechanical properties of the blend films were measured. The results show that with the content of glycerol increasing, the solubility decreases. The blend films became insoluble when the mass ratios of glycerol/SF are more than 10%. When the content of glycerol is low, there is a little of Silk Ⅱ structure and almost no Silk Ⅰ structure in blend film. With glycerol increasing, the crystallinity of Silk Ⅰ  increases while that of Silk Ⅱ decrease in blend film. When the content of glycerol exceeding 10%, in which content that silk fibroin become insoluble, the crystalline structure of SF is mostly changed into Silk Ⅰ and there is almost no Silk Ⅱ structure. Mechanical properties indicated that glycerol could significantly improved the flexibility of silk films. In summary, the crystal structure is changed to Silk Ⅰ and the crystallinity of silk fibroin is increased so that the solubility of silk fibroin is significantly reduced by adding glycerol when casting film.