bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Characterization of Multi-Functional Substituted POSS
Authors: Zhang Li Ying , Zhao Xiao Jing , Chen Ping , Fan Sheng Di
Published: July 2012

Five different multifunctional nitro octaphenyl silsesquioxane (NPS) were Synthesised and reduction was carried out to obtain amino octaphenyl silsesquioxane(APS). These compounds were characterized with elementary analysis, fourier transform infrared(FTIR), nuclear magnetic resonance (NMR, 29Si), wide-angle X-ray diffraction(XRD) and thermogravimetry (TG). Experiental results showed that the longer the nitration time, the more nitro connected to the OPS, but not positively, nitro number remained unchanged after five hours. NPS has good thermal stability than corresponding APS under 450°C, and the thermal stability of APS are decrease with the increase of amino number.
Synthesis and Crystal Structure of a New Copper(II) Coordination Polymer [CuC16 H18 N4O4S]n*
Authors: Li Jia Gui , Zhu Wan Ren , Ding Shu Hong , Chen Yuan , Zhu Yu Lin , Huang Zhao Yu
Published: July 2012

A new one-dimensional [CuC16H18N4O4S]n(1) was synthesized by the self-assembly of a ligand 2,5-thiophenediformates, 3,5-dimethylpyrazole and copper(II), and characterized by elemental analysis, IR and single-crystal X-ray diffraction. 1 crystallizes in monoclinic, space group C2/c with unit cell parameters, a=18.6156(4), b=5.96110(10), c= 18.1598(4)Å, =115.467(2)°, Z=4, V=1819.37(7)Å3, Mr = 425.94, Dc = 1.555g/cm3, μ=1.345mm-1, and F(000)= 876. The final R and wR are 0.0328 and 0.0816 for 7611 observed reflections with I>2σ(I). 1 shows an infinite 1-D polymeric chain structure based on the repeated basic units Cu(II)(3,5-dimethylpyrazole)2(2,5-thiophene diformate). The Cu(II)center acts as the joint of the unit, and is coordinated in a slightly distorted octahedral geometry comprised of four O atoms from two different 2,5-thiophenediformate ligands and two N atoms of two trans 3,5-dimethylpyrazole ligands.
Phenolic Resin Based Supramolecular Aggregates-Novel In-Depth Profile Modifier for Oil Reservoir
Authors: Gao Guo Qiang , Sun Li Mei , Wang Lu Shan , Tian Zhong Qiang , Tang Hong Tao , Wang Jian
Published: July 2012

The aggregates size, plugging and propagation properties for supramolecular aggregates based on phenol-formaldehyde resin have been investigated by measurement of hydrodynamic diameter, filtration with nuclear pore film and plugging test with sand-pack core. The results show at the condition tested, supramolecular aggreates have an average hydrodynamic diameter of about 450 nm, and can sufficiently plug 1.2 μm-nuclear pore film. The aggregates can plug, propagate, replug and repropagate in porous media, which is an obligatory property of an in-depth profile modifier for oil reservoir.
Intramolecular Nucleophilic Substitution in the Hydrolysis of Bis(4-Nitrophenyl) Phosphate Ester Catalyzed by the Metallomicelle
Authors: Wang Min , Xu Li Qin , Li Ci , Jiang Bing Ying , Xie Jia Qing
Published: July 2012

A macro-cyclic Schiff base ligand and the corresponding Cu (II) and Ni (II) complexes were synthesized and characterized. And the catalytic efficiency of the metallomicelles made of these complexes and noninonic micelle Brij35, as mimetic hydrolytic metalloenzyme, was investigated in the catalytic hydrolysis of bis(p-nitrophenyl) phosphate (BNPP) in this paper. The results show that the rate of the BNPP hydrolysis in the metallomicelles is about 106 -fold faster than that of the BNPP spontaneous hydrolysis in aqueous solution at the same conditions. The analysis of the characteristic absorption spectra of the hydrolytic reaction systems indicates that the key intermediate, composing of BNPP and Ni(II) or Cu(II) complexes, has been formed and the catalytic hydrolysis of BNPP is an intramolecular nucleophilic substitution reaction. Based on the results of characteristic absorption spectra, the mechanism of BNPP catalytic hydrolysis has been proposed and also the corresponding kinetic mathematical model has been established.
Electrochemical Performance Research of Mg Ion Doped LiMnPO4/C
Authors: Wei Zeng Fu , Su Wei , Liu Shi Nian
Published: July 2012

LiMn1-xMgxPO4/C(x=0, 0.01, 0.04, 0.05, 0.1) were synthesized by using wet-ballmilling and solid-state calcining with phenolic resin as the carbon source. All samples are single phase with a similar morphology, but the cation substitution results in a crystal lattice shrink because of the smaller ionic radii of Mg2+, the particles are small and homogeneous. CV, EIS and charge/discharge measurement shows that the Mg substitution leads to a significantly increased reversible capacity due to the enhanced electrochemical kinetics. LiMn0.96Mg0.04PO4/C calcined at 600°C has a discharge capacity of 144mAh/g at 0.05C. When charging-discharging by CC-CV-CC mode at high rates, LiMn0.96Mg0.04PO4/C composite exhibits a good cycle and rate performance.
Highly Selective Caffeine Coated-Wire Electrode Based on the Molecularly Imprinted Polymer
Authors: Guo Xiao Jun , Wei Shou Lian , Liu Yong
Published: July 2012

The molecular imprinted polymer (MIP) was synthesized by precipitation polymerization with caffeine as template, methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linker. A selective electrode for the potentiometric determination of caffeine in the aqueous medium was developed using the MIP-modified coated-wire electrode. The electrode shows response for caffeine in a concentration range of 1.0×10-8 to 1.0×10-5 M with a lower detection limit of 5.0×10-9 M. The electrode can be used for more than 100 times. The response time is 15 s and the signal is constant in the pH range 6.4 to 9.0. The electrode can be successfully applied for the monitoring of caffeine in syrup sample.
Electrochemical Properties of Natural and Modified Pyrite
Authors: Wang Da Gang , Fan Li Ren , Fan Chou
Published: July 2012

Pyrite utrafine powder was yielded through processing natural pyrite, including gravity separation, flotation and airflow grinding, which the contents of Fe and S are 45.30wt% and 50.95wt% respectively and the mean grain size is 13μm. Pyrite powder modified by fatty acid salt A was investigated by TG/DSC, XPS and XRD. The results indicate that the phase of powder is mostly pyrite FeS2 coating with organic modifier, and S exists in the form of [S2]2- principally on modified pyrite surface. Furthermore, electrochemical impedance spectroscopy, cyclic voltammetry measurement and galvanotactic current charge and discharge methods were applied to exhibit the electrochemical performance of pyrite sample. The results show that modified pyrite has lower charge transfer resistance and higher conductivity than that of natural pyrite, and the specific discharge capacity is as high as 850mAh/g under 0.354A current at room temperature and the cutoff of 0.5V closing to the theoretical specific capacity of pyrite (890mA•h/g), and the voltage plateau is 1.44V.
Preparation and Characterization of High-Density Li0.99W0.01FePO4/C Composite Cathodes
Authors: Zhong Mei E
Published: July 2012

High tap-density Li0.99W0.01FePO4/C composite have been synthesized via a simple and low-cost solid state-carbothermal reduction method, using Fe2O3and citrate ferric as the Fe3+precursors and citric radical containing in citrate ferric as both carbon source and reducing agent. The structure, morphology, and physicochemical properties of Li0.99W0.01FePO4/C composite were characterized by XRD, SEM, laser diffraction and scattering measurement, and tap-density testing. It is observed the particle distribution of the Li0.99W0.01FePO4/C composite is bimodal distribution. Because of the smaller particles filling in the space between the larger particles, the Li0.99W0.01FePO4/C composite exhibits less vacancy, which resulted in a high tap density of 1.50 g•cm-3. The Li0.99W0.01FePO4/C composite also shows good rate capability and cycle performance. At current densities of 0.2, 0.5, 1.0 and 1.5 C, the composite material has initial discharge specific capacity of 141, 133, 130 and 125 mAh•g-1, respectively.
Stability and Transport Conductivity of Perovskite Type BaZrxCe0.8-xNd0.2O3-δ
Authors: Zhan Shi Jing , Zhu Xue Feng , Wang Wei Ping , Yang Wei Shen
Published: July 2012

Solid oxide components such as electrolyte for solid oxide fuel cell require chemical stability and high conductivity. Substituting Zr for Ce in BaCe0.8Nd0.2O3-δ improves the chemical stability but reduces conductivity. The objective of this work was to study the optimization of conductivity and chemical stability by changing the ratio of Ce to Zr in BZCN. Perovskite type BaZrxCe0.8-xNd0.2O3-δ (BZCN) powders were prepared by an EDTA–citric acid (EC) process. BaZrxCe0.8-xNd0.2O3-δ (x≥0.4) oxides show good chemical stability against carbon dioxide. The conductivities of sintered samples increased with the temperature and decrease with their Zr content. The good chemical stability and conductivity of BaZr0.4Ce0.4Nd0.2O3-δ is potential to be practically used with both high conductivity and good stability
The Relationship between Gel Content and Drying Shrinkage
Authors: Sun Jia Li , Sun Dao Sheng , Wang Ai Guo , Deng Min , Liang Zuo Qiao
Published: July 2012

In this paper, the relationship between gel content and drying shrinkage has been investigated. The drying shrinkage for different specimens was tested by comparator. Modified Water Absorption Method was used in the semi-quantitative analysis of gel content. Found that (1) The sample, which is high in activity, produces more gel, so does the drying shrinkage. (2) The drying shrinkage is linear correlation with gel content. (3) Sample with higher gel content has thinner pore structure.
Hydrothermal Synthesis and Growth Mechanism of Mesoporous ZnO Microtubes
Authors: Li Yan , Zou Yun Ling , Zhou Qing Jun
Published: July 2012

Porous ZnO microtubes have been synthesized via a facile hydrothermal method based on nanoparticle splicing growth and the preferential etching strategy in the hydrothermal reaction system with high supersaturation. The ZnO tubes have hexangular wurtzite structure with a dimension of about 6 to 12 m in length, 4 m in diameter and about 40 nm in wall thickness, which is made of numerous mesopores with diameter ranging from 40 nm to 200 nm.
Hydrothermal Synthesis of Rare-Earth Doped NH4Y3F10 Sub-Microcrystals with Down-Converting Luminescence
Authors: Xu De Kang , Yang Sheng Hong , Zhang Yue Li
Published: July 2012

A series of NH4Y3F10 sub-microcrystals had been prepared by a one-step hydrothermal route. The morphological and structural properties of the sub-microcrystals were studied by scanning electron microscopy (SEM) and powder X-ray diffraction (XRD). The results of SEM and XRD suggested that NH4Y3F10 sub-microcrystals have irregular shapes with their sizes varying from 100nm to 500nm and the structures of obtained NH4Y3F10 sub-microcrystals are cubic phase. Additionally, the down-converting(DC) phenomenon have been observed under UV excitation in (Yb3+, Nd3+) co-doped NH4Y3F10. It is found that luminescent efficiency of 10%Yb, 1%Nd co-doped NH4Y3F10 sub-microcrystals is stronger than that of 10%Yb, 5%Nd co-doped NH4Y3F10 sub-microcrystals. The energy transfer mechanism of the emission spectra of (Yb3+, Nd3+) co-doped NH4Y3F10 is discussed.
Synthesis of MoO3 Nanostructures by a Solution Method
Authors: Du Kai , Wei Rong Hui , Bai Ya Nan , Gu Yadi , Li Li Ben
Published: July 2012

Synthesis and characterization of microsheets, microrods, microflowers and microspheres of orthorhombic phase molybdenum oxide (MoO3) were reported. The reaction between ammonium molybdate and hydrochloric acid was used to prepare MoO3microstructures and followed by annealing in air at 400oCfor 2h. The combined techniques of X-ray powder diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and Raman spectroscopy were used to investigate the effect of pH and additives on the as-prepared samples. Results indicated that they were of microsize. With alcohol as an additive, the sample was plate-like MoO3at pH=2.5, and it was a mixture of MoO3and MoO3•0.55H2O of irradiative corolla at pH=1. The sample obtained by hydrothermal was MoO3flowers. Meanwhile, when silane coupling agent was introduced as the additive, the sample was MoO3spheres.
Preliminary Study of Refined Naphthalene Production with Fractional Crystallization
Authors: Xu Gui Ying , Gao Zhan Xian , Zhang Jian , Bai Jin Feng
Published: July 2012

In order to obtain optimized operating condition for industry naphthalene purification using fractional crystallizing method, the influence of heating rate, crystallizing times, holding time and cooling rate on the yield and purity of industrial naphthalene were studied. The industrial naphthalene from AISC Chemical General tar workshop was used as starting material in the study. The results show that the yield and purity of refined naphthalene can achieve 94.2％ and 99.30％ respectively, when the heating rate is 1.2°C/h, the cooling rate is 3°C/h, holding time is 5 hours and the crystallizing times is 3. The result of present study provides a theoretical foundation for the actual production and technology improvement of naphthalene purification.
Separation Copper Ions from Aqueous Solution by Emulsion Liquid Membrane Using Novel PAMAMG4-1,2-Octenoxid Dendrimer as Carrier
Authors: Zhang Chang Hua
Published: July 2012

PAMAMG4-1,2-octenoxid dendrimer was prepared and used as carrier in ELM to extract copper ions. The membrane was prepared by dissolving PAMAMG4-1,2-octenoxid dendrimer and Span 80 in chloroform. The internal phase is aqueous solution of hydrochloric acid. Effects of operating parameters such as carrier concentration, surfactant concentration, hydrochloric acid concentration in the internal phase, emulsification time and emulsification speed on the membrane stability were studied. In addition, the effect of carrier concentration, surfactant concentration and hydrochloric acid concentration in the internal phase on the extraction efficiency was also investigated. The results showed that PAMAMG4-1,2-octenoxid dendrimer is a suitable carrier for copper ions in ELM system.
Preparation of Composite Particles Containing Nano-CuO and Micron Flake Graphite
Authors: Liu Cheng Gong , Yuan Zhi Gang , Ba Shu Hong
Published: July 2012

Nano-CuO particles are prepared by using Cu(NO3)2 and NH4HCO3 as the starting materials and pure water as the solvent. And use high-energy ball milling method to make nano-CuO particles embeded in the crystalloid surface of graphite to form composite particles. The products of nano-CuO and composite particles are characterized by using techniques such as X-ray powder diffraction, FTIR-spectroscopy, scanning electron microscopy, and separator-size analyzer. The results show that the average size of CuO particles is 11.2nm, the Median diameter of composite particles is 8.43μm. After the graphite is rapidly ball milled and loaded nano-CuO particles. The lamellar and pore structure of graphite are well maintained, And nano-CuO particles are loaded on the top of the hole and the hole wall.
Effect of Carbon Source Content on the Carbothermal Synthesis of AlN Powders Using a Combustion Synthesis Precursor
Authors: Chu Ai Min , Qin Ming Li , Jia Bao Rui , Lu Hui Feng
Published: July 2012

AlN powders were synthesized by carbothermal reduction method using a combustion synthesis precursor derived from aluminum nitrate (oxidizer), glucose (carbon source), and urea (fuel) mixed solution. Effects of carbon source content on the combustion temperature of solutions, the particle size and morphology of the precursors and the synthesized AlN were studied in detail. The results indicated that a regular variation in the particle size and morphology of precursors had been observed with the increasing molar ratio of glucose to aluminum nitrate (C/Al). The products prepared with (C/Al=8–12), calcined at 1500 oC for 2 h, could have completed the nitridation reaction, while the nitridation products prepared with (C/Al=4 and 16) are opposite. The nitridation products prepared with (C/Al=8–12), calcined at 1500 oC for 2 h, are comprised of well-distributed spherical particles of AlN with the average size ranging from 50 to 80 nm.
Comparison between Conventional and Microwave-Assisted Synthesis of Cu-Containing Layered Double Hydroxides
Authors: Chen Chun Xia , Zhang Kun , Li Bin
Published: July 2012

Cu-containing Layered Double Hydroxides (Cu-LDHs) prepared in a microwave field (Cu-LDHs-b) differs drastically according to the appearance, chemical component and the catalytic activity when compared with conventionally prepared sample (Cu-LDHs-a). From the TEM images, it is obvious that the particle size range of Cu-LDHs-b with 30～90 nm is narrower than that of Cu-LDHs-a with 30～120 nm, and the dispersibility of Cu-LDHs-b is better than that of Cu-LDHs-a. ICP-AES characterization shows that raw material utilization ratio of Cu-LDHs-b is higher than that of Cu-LDHs-a. Furthermore, Cu-LDHs-b exhibites higher catalytic activity than Cu-LDHs-a in the phenol hydroxylation with H2O2. Therefore, the microwave-assisted synthesis is an ideal method for synthesis of nano-Cu-LDHs.
Study on Pressure-Cyanide Dissolution of Metal Platinum Powder
Authors: Yan L. , Zhao J.S.
Published: July 2012

A research study has been undertaken to develop the fundamentals of a method for the direct dissolution of Metal Platinum. At room temperature and pressures, the reaction between sodium cyanide and platinum group metals (PGMs) does not occur because of poor kinetics. However, at elevated temperatures between 20°C and 180°C, PGMs can be dissolved by sodium cyanide like the reaction of gold. In this work, the dissolution of Platinum was measured in pressure clear cyanide solution. The data at different cyanide concentrations, different temperature and different oxygen pressure are obtained. With increasing cyanide concentration and oxygen pressure, the dissolution first increased to a maximum value and then decreased. With increasing temperature the dissolution is increased. The dissolution was found to have a relation of the cyanide and oxygen level. The dissolution was independent of rotation speed for oxygen-saturated solutions and cyanide concentrations above 5 mol.m-3 and was well below chemical reaction-limited for cyanide and oxygen.
Theoretical and Experimental Study on Pneumatic Classification of Fine-Metal-Powder
Authors: Ma Rui Xin , Chang Jia Ning , Shi Chang Sheng , Zhang Xin Xi
Published: July 2012

With the development of powder metallurgy industry, the fine-metal-powder classification becomes one of the vital techniques in powder technology. A pneumatic classifier without screen and mechanical moving parts is designed and developed. Theoretical analysis and experiments of Pneumatic-Classification was conducted. The oversize ratio in fine powder can be reduced to less than 5% and the undersize ratio in coarse powder less than 15% when the air flow is suitable. The classification effect is satisfactory for the customers.
CuS Nanotubes:Microwave-Solvothermal Synthesis and Photocatalytic Property
Authors: Liu Xiao Lin , Zhu Ying Jie , Yang Bin , Zhang Qian , Li Zhi Feng
Published: July 2012

Copper sulfide (CuS) nanotubes assembled by nanoparticles were successfully synthesized by reaction thiourea with Cu(OH)2nanowire precursor which was obtained using CuCl2and NaOH as raw materials in the solvent ethylene glycol at 80 °C by a facile microwave-assisted solvothermal method. The forming influencing factors of CuS nanotubes were investigated. One of the advantages of this method is that the preparation of CuS nanotubes can well duplicate the shape of the nanowire precursor, thus the simplicity and low cost can be achieved. The products are characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The photocatalytic property of the CuS samples was also investigated.
Controlled Synthesis of Mono-Dispersed Cerium Oxide Nano Powders via a Mixed Solvothermal Route
Authors: Ma Zhen Xiong , Zhang Xing Kai , Zhang Qi Tao , Jiang Yan , Liu Ping , Ye Jia Mei , Liu Jun Liang , Zhang Ming
Published: July 2012

In this paper, mono-dispersed cerium oxide nano powders have been synthesized via a mixed solvothermal route. The influences of solvents’ compositions and solvothermal temperatures on the crystallization of cerium oxide have been investigated. The results indicated that the formation temperature decreased when the mixed solvent was used and the existences of alcohols played as the reducing agents and delayed the crystallization of cerium oxide, which had great influences on both yield ratios and morphologies of the synthesized nano powders.
Effect of Mo and Ce Additives on Redox Behavior for Hydrogen Storage and Release of Iron Oxide Mediums
Authors: Kim Young Ho , Kang Eun Jee , Lee Su Gyung , Kim Hyo Sub , Park Chu Sik
Published: July 2012

The hydrogen reduction and water-splitting oxidation for hydrogen storage and release on the iron oxide mediums with Ce, Mo or Ce-Mo additives were carried out using a fixed bed reactor at atmospheric pressure. A sole Ce additive was an outstanding material for the improvement of the reactivity in the reduction and oxidation of iron oxide medium, even though the medium with Ce was easily deactivated during repeated cyclic reactions due to sintering. A sole Mo additive was a good material for the improvement for the durability. In the mediums with the Ce-Mo additives, therefore, the degree of deactivation and the reactivity of the mediums were gradually decreased with the increase of the amount of Mo. Among the iron oxide mediums with Ce-Mo additives, a FeCeMo-5 medium exhibited the good durability while the maintaining the considerable reactivity during the cyclic reactions.
Preparation and Characterization of Graphene by the Oxidation Reduction Method
Authors: Long Yin , Wang Jian Fang , Lv Ya Nan , Tao Cheng An , Xia Lin , Zhu Hui
Published: July 2012

We prepared graphite oxide (GO) from natural graphite by the modified Hummers method. Then graphene was prepared by ultrasonically dispersing GO in the presence of hydrazine hydrate. The samples were characterized by FTIR, Raman, Scanning electron microscope (SEM) and Transmission electron microscope (TEM). The results suggest that the graphite is oxidized to covalent bond-type graphite intercalation compounds with various oxygen functional groups (C=O, C-OH, -COOH and C-O-C). Results show that the functional groups on graphite oxide surface are mostly removed by hydrazine hydrate and graphene presents translucent slide with curly edge.
Study on Preparation of Titanium Dioxide from Low Iron and Rich Titanium Slag with Acid Hydrolysis Technical
Authors: Hu Zhi Yong
Published: July 2012

Titanium dioxide is an important inorganic chemical product, and low iron and rich titanium slag can be made into titanium dioxide. In this paper, process parameters for preparing titanium dioxide were investigated. The results show that with the increase of sulfuric acid concentration, curing time and curing temperature, the rate of sulfuric acid hydrolysis rate will be improved, as well as charging temperature. According to the orthogonal test, the optimum process parameters condition of sulfuric acid is 95% sulfuric acid, 180°C reaction temperature, and 120min curing time.
Valence Electron Structure Analysis of Intrinsic Hardness for Diamond and c-BN
Authors: Zhang Xiao Jun , Gao Bin , Cheng Peng Fei
Published: July 2012

Based on the Pauling’s nature of chemical bond, the valence electron structures of diamond and c-BN crystals have been constructed. Then the relationship between covalent bond and glide plane system is analyzed. The results show that the hardness of diamond and c-BN is correlated to the covalent electron structure and the slip system of crystals. The hardness for diamond and c-BN so large is explained satisfactory form valence electron structures.
Liquid-Liquid Structure Transition and its Effects on Solidification Behavior of Binary Alloys
Authors: Xi Yun , Li Xian Fen , Zu Fang Qiu
Published: July 2012

In our work, some anomalous changes, namely the temperature-induced liquid-liquid structure transitions, were observed at the temperature hundreds degrees above the corresponding liquidus in some binary alloys. Based on the results of liquid structure transitions, corresponding solidification experiments have been carried out on the alloys melted and held at the temperature above or under the liquid-liquid structure transition (L-LST), respectively. It is found that L-LST has a significant effect on solidification behavior and microstructure. There is a general rule that the super-cooling degree increases and the microstructure becomes finer cast from the liquid experienced L-LST.
Wear Mechanism and Self Lubrication of Engineering Ceramics at Elevated Temperatures
Authors: Liu Hao , Cai Ye Bin
Published: July 2012

Friction and wear tests of Al2O3 and SiC were conducted from room temperature to 1200 °C both in air and in vacuum. Results show that the wear mechanism of Al2O3 is dominated by micro fracture, debris abrasive and delamination at temperatures below 600 °C, while is controlled by plastic deformation and recrystallization among 600~1200 °C, resulting in an obvious decrease of wear loss. The wear rate and surface microstructure of SiC are closely depending on the testing temperature, atmosphere and contact pressure. Oxidation of SiC at elevated temperatures plays important role on the wear rate. Self lubrication of both Al2O3 and SiC at high temperatures was observed, which is mainly depending on the formation of a specific surface layer composed of nano-particles or very thin glassy film.
Synthesis of CoO and Co3O4 Nanoparticles by Salt-Assisted Combustion Method
Authors: Ji Ming Wei , Ma Zhen Ye , Xu Juan , Zhang Li Xiong , Zhao Feng Qi
Published: July 2012

In the present study, CoO, which is hard to synthesize because of the chemical activity of cobalt metal, and the popular Co3O4 have been successfully controlled produced by a salt-assisted combustion method (SACM), in which Co(NO3)2•6H2O, polyethylene glycol (PEG2000) were chosen as oxidant and fuel respectively. The CoO and Co3O4 nanoparticles were investigated by high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), x-ray diffraction (XRD), simultaneous thermogravimetric and differential thermal analysis (TG-DTA) and N2 adsorption. It is found that the pure CoO were obtained whatever adjusting the weight ratio of Co(NO3)2•6H2O and PEG2000 in the absence of inert salt. While, well-dispersed Co3O4 nanoparticles with a high specific surface area were successfully obtained with the introduction of NaCl or KCl in the system, which results from the fact that the introduction of inert inorganic salt as a agglomeration inhibitor into the redox mixture precursor led to the breakup of fractal nanocrystallite agglomerates. A mechanism was proposed to illustrate the possible formation processes and the role of the inert inorganic salt.
Solid-State Photocycloaddition Reactions of Tri-2-Pyrones with Benzophenone
Authors: Wang Wei Dong , Shimo Tetsuro
Published: July 2012

Solid-state photocycloaddition reactions between tri-2-pyrones (1a,1b) with benzophenone (2) gave the corresponding oxetane derivatives (3a:3a′=1:1 and 3b:3b′=1:1, 1:2 adducts) with high site- and regioselectivity across the C5-C6 , C5′-C6′ and C5′′-C6′′ double bonds in 1 via the triplet excited state of 2. The site- and regioselectivities were explained by MO calculations. The hydrogen-bonding interaction between 2 and 1a, 1b and the triplet reaction mechanism were also explained by the IR analyses and the quenching experiments, respectively.
Synthesis and Phase Behavior of Chiral Liquid Crystal Elastomers Containing Cholesteryl Group
Authors: Jia Ying Gang , Song Kun Ming , Zhang Bao Yan
Published: July 2012

The synthesis of new side chain cholesteric liquid crystalline elastomers (ChLCEs) containing the cholesteric monomer M and the flexible non-mesogenic crosslinking agent C, is described. The selective reflection of light for M was characterized with UV/Visible/NIR. The phase behavior and mesomorphism were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and X-ray diffraction (XRD). The effect of the content of crosslinking units on the phase behavior and mesomorphism of elastomers P1– P8is discussed. The ChLCEs exhibit elasticity, reversible phase transitions, and cholesteric Grandjean texture. The experimental results demonstrate that the glass transition temperature and isotropic temperature of ChLCEs decrease with increasing the content of crosslinking unit, but the cholesteric phase is not disturbed.
Synthesis and Mesophases Study on 2,3,6,7,10,11-Hexaheptylcarboxyltriphenylene
Authors: Wang Yi Fei , Zhang Ming Xia , Zhang Chun Xiu , Wu Hao , Pu Jia Ling
Published: July 2012

A triphenylene-based discotic compound 2,3,6,7,10,11-hexaheptylcar-boxyltriphenylene was synthesized. The structure of the compound was determined by1HNMR and FT-IR spectrum and its mesomorphism was clarified by DSC and POM methods. The carrier mobility was measured using time-of-flight method and has a value of 1.2 × 10-1cm2V-1s-1.
Chiral Separation of Non-Natural Amide Amino Acid by Capillary Electrophoresis with CD Derivations as Chiral Selective Material
Authors: Li Bao Hui
Published: July 2012

A capillary electrophoresis (CE) method for the separation of four kinds of enantiomers of non-natural carboxylic amino acid was built while hydroxypropyl-β- cyclodextrin (HP-β-CD) derivations as chiral selective material. Several different β-CD derivatives were tested for the chiral separation of non-natural carboxylic amino acid, and it was proved that HP-β-CD could show better chiral selectivity. The separation of enantiomers of amino acid was obtained by CE in a 50-μm i.d.×60 cm (effective length 45 cm) fused-silica capillary at 18 kV voltage, while 10 mM phosphate acted as running buffer and HP-β-CD served as selective material. The detective wavelength was set at 254 nm.
Synthesis and Properties of Novel Triphenylamine Derivatives Containing Bipyridine Units
Authors: Lv Hai Jun , Li Xiang Gao , Wang Shi Rong , Gao Wen Zheng
Published: July 2012

Compounds (S1-S3) containing triphenylamine donors, bipyridine acceptors and olefinic linkers were synthesized and characterized. Three compounds have excellent solubility in common solvents and tend to form solid films. The peaks of emission of S1-S3 are in the range of 476nm-504nm on solid films, corresponding to blue light emission. S1-S3 have fluorescence lifetime exceeding 2.05ns and absolute fluorescence quantum yield above 22% in dilute chloroform solutions. Three compounds possess glass-transition temperatures superior to 63°C. The HOMO levels are in the range of -5.17eV - -5.13eV to facilitate hole injection. The properties of S1-S3 indicate that these compounds are promising candidates as hole-transporting materials or blue light-emitting materials in organic light-emitting devices.
Synthesis of O-Nitrophenylacetaldehyde
Authors: Zhang Zhen Ming , Li Shu An , Li Run Lai , Zhu Kai , Wang Guang Jie
Published: July 2012

O-nitrotoluene is condensed with N, N-dimethylformamide dimethyl acetals in the presence of piperidine and DMF to yield trans-β-dimethylamino-2-nitrostyrene which undergoes hydrolysis in the 18% HCl aqueous solution to obtain o-nitrophenylacetaldehyde with yield of 83% and purity of 98.1% respectively.
Synthesis of Spinel Li2MnO3 and its Ion-Exchange Property for Li+
Authors: Jiang Jin He
Published: July 2012

Compound [Li2MnO3], a spinel-type metal compound, was prepared by a solid state reaction crystallization method. The results showed that the Li+ extraction/insertion be progressed mainly by an ion-exchange mechanism. Results of column test indicated, that the exchange capacity obtained from tests for Li+ in 0.1mol/L HNO3 solution is 7.0 mmol•g-1.It had a memorial ion-sieve property for Li+
The Screening of Optimal Ganoderma lucidum and the Effect of Medium Substrate on Bioactive Metabolite in Submerged Culture
Authors: Cui Mei Lin , He Guo Qing
Published: July 2012

To determine an optimal G. lucidum strain, we made the production of mycelia biomass, EPS, IPS, IT, ET as indicators, among the five tested strains, the American G. lucidum was screened, and the production of mycelia biomass, EPS, IPS, IT, ET could reach 2.013g/100 ml, 11.2988 mg/100ml, 23.7800 mg/10ml, 45.5412 mg/100ml, 11.1417 mg/100ml, respectively. On the other hand, according to the screening of carbon and nitrogen sources as well as their concentration, the suitable carbon and nitrogen was 3% malt powder, 1.5% yeast extract. So we can use the fermentation culture for the following research, which was as follows：3% malt powder, 1.5%yeast extract, 0.3% KH2PO4, 0.15% MgSO4, 0.005% VB1.
Synthesis of 1,2,13,14-Four Carboxyl-24-Crown-8
Authors: Wang Feng Jie
Published: July 2012

The corresponding salt of 1,2,13,14-four carboxyl-24-crown-8 was synthesized using the triethylene glycol and the sodium-potassium tartrate as mainly raw materials, then the goal product:1,2,13,14-four carboxyl-24-crown-8 was taken through the hydrochloric acid acidification.The idea synthesis technological conditions are :potash as catalyst,tetrahydrofuran as solvent, Triethylene glycol added using drops method, the mole ratio of reaction ( triethylene glycol : potassium tartrate sodium) is 2:1, the highest response temperature is 170 °C, for 20 hours, acidified for 4 hours, crystallized temperature at 0°C.
Improved Water-Solubility of Phytosterol by Hydroxypropyl-β-Cyclodextrin
Authors: Zhang Xiao Yan , Peng Yong , He Guo Qing
Published: July 2012

Phytosterol has been shown to lower the serum cholesterol concentrations, but its low solubility in water restricts its application. In this study, hydroxypropyl-β-cyclodextrin was used to improve the water-solubility of phytosterol. Phase solubility study pointed out the formation of 1:1 inclusion complexes between phytosterol and hydroxypropyl-β-cyclodextrin. The initial dissolution rate was remarkedly improved in the first two minutes. The suitable solvent and temperature for complex formation was n-butanol and 40°C.
Synthesis, Characterization and Neurotoxicity Screening of Schiff Base Ligands and their Complexes
Authors: Abu Bakar Ahmad Fauzi , Bahron Hadariah , Kassim Karimah
Published: July 2012

Two ligands and four complexes are successfully synthesized by reacting 1,8-diaminonapthelene with aldehyde/ketone derivatives in ratio amine:aldehyde/ketone (1:2) for ligands formation and 1:1 ratio (ligand:metals) for complexes formation. The compounds were characterized through CHNS elemental analysis, IR spectroscopy, 1H NMR spectroscopy, melting point determination, and magnetic susceptibility determination. The neurotoxicity screening of compounds was screened using neuroblastoma SH-SY5Y cell lines and it was indicate the cells were non-toxic either for ligands and complexes after 24 hours exposure.
The Extraction of β-Carotene from Red Yeast Cells by Supercritical Carbon Dioxide Technique
Authors: Wang Sui Lou , Liu Wei , Wang Hai Xiang , Lv Chun Hui
Published: July 2012

The extraction of β-carotene from red yeast cells by supercritical carbon dioxide (SC-CO2) was studied. The determined conditions from the orthogonal designed experiments were as follows: extraction pressure of 30 MPa, temperature at 40 °C, CO2 volume of 20 Kg/h and extraction time for 90 min. Using SC-CO2 technique to extract β-carotene from the yeast cells is possible, but some factors that affect the extraction result should be further investigated.
Manufacture and Nutritional Analysis of Chinese Yam Jam
Authors: Hu Guo , Hu Shang Qin
Published: July 2012

As a means of developing and utilizing Chinese yam, the tuburous roots, as the primary ingredient, underwent processing. They were first peeled, cleaned and boiled, then mashed into a jam-like substance along with additional materials. The process was complete after bottling and sterilization. Chemical and instrumentation tests were conducted on the jam to identify the nutritional components. The results showed that the jam was a bright gold color with delicious taste and many nutrients. Protein content was 4.21%, and there were 17 types of amino acids and 8 types of amino acid essential to humans. Fat was measured at 1.82% and numerous vitamins and minerals were identified. Chinese yam jam is a condiment rich in nutrients and taste and suitable for old and young alike. This article provides a scientific basis for the manufacture and usage of the Chinese yam.
Effect of Different Processing on Corn Starch and Protein
Authors: Zou Jian , Gao Hai Yan , Zeng Jie
Published: July 2012

Scanning electron microscopy of samples showed that corn flour granules by fermented and wet-milling were angular, pentagonal or elliptical similar to native starches while samples with extruding and cooking were irregularly fibrous and large granules. Protein of samples with wet-milling exhibited an obvious DSC endotherm, To 85.81°C, Tp 92.95°C, Tc 101.73°C and ΔH 1.614J/g.While the fermented and extruded samples had no endotherm. Ultra-violet absorption spectrometry showed that absorbance of fermented and extruded samples increased and the λmax were slightly red shift. The λmax were 294nm, 297nm and 310nm for wet-milling , fermented and extruded flour, respectively. SDS-PAGE patterns of wet-milling flour contained four bands, fermented samples only three bands while extruded samples had same bands with dry-milling.
Preparation of Cellulose-Graft Water Retaining Agent: Effect of Reaction Temperature and Initiator
Authors: Miao Zong Cheng , Wang Fang , Deng Deng , Zhang Yong Ming , Wang Lei , Li Zhong Jin
Published: July 2012

Grafting vinyl monomers onto natural cellulose become a preferred method to derive water retaining agent because it afforded unique environmental and commercial advantages. In current work, a series of water retaining agent were prepared by radical solution polymerization of cellulose, partially neutralized acrylic acid and acrylamide using grafted agents as an initiator and N, N-methylenebisacryl- amide as a crosslinker. Fourier transform infrared spectroscopy spectra proved that acrylic acid and acrylamide were grafted onto cellulose backbone and N, N-methylenebisacryl- amide participated in polymerization. The effects of reaction conditions of reaction temperature and initiator amount to water retaining agent were studied using water absorbencies as evaluation standard, the optimum preparation technology was decided.
Synthesis of Starch-Graft-Polyacrylamide by Salt Solution Media Polymerization
Authors: Li Wen Bing , Huang Ting Ting , Wang Guang Hua
Published: July 2012

Starch-graft-polyacrylamide (St-g-PAM) was prepared using a salt media polymerization technique, and characterized by FITR. The type of starch and the synthesis method of different system were studied through the mass of product, the percentage of grafting (PG) and the monomer conversion (MC), and the difference polymerization system. The results showed that the pretreated starch and the salt solution system, respectively, were more advantageous than the raw starch and the aqueous solution system. The intrinsic viscosity, transmittance, product loss, penetration and apparent viscosity of St-g-PAM by salt solution polymerization were 12.49 dL•g-1, 18.6%, 0.56%, 53.96, 18.40 Pa•S, respectively. The method could get bigger branched-chain molecular than the others with high yield, high monomer conversion, high the percentage of grafting, low product losses and easy post-processing
The Interlaminar Tensile Strength of Mesophase Pitch-Unidirectional Carbon/Carbon Composites Adding Natural Flake Graphite
Authors: Hu Nai Qiang , Liu Xiu Jun , Feng Zhi Hai , Fan Zhen , Li Tong Qi
Published: July 2012

In this work, carbon/carbon composites were prepared by a hot-pressing technique at a relatively low temperature. The effect of Graphite content on the mechanical properties of mesophase pitch-unidirectional carbon/carbon composites was investigated by tensile testing, and the fracture surfaces of carbon/carbon composites are observed by scanning electron microscopy (SEM). Results showed that the interlaminar tensile strength of the carbon/carbon Composites was improved as content of natural flake graphite in raw material increased from 5% to 10%. However, a decrease of interlaminar tensile strength was observed when content of natural flake graphite was higher than 10%. Even the interlaminar tensile strength is lower than that of composites which is not added Graphite.
Photocatalytic Removal of Cu(II) Ions from Water Using TiO2-Modified Bamboo Charcoal
Authors: Xia Chang Bin , Liu Chun Hua , Wu Dao Xin
Published: July 2012

The photocatalytic reduction of Cu(II) under UV irradiation in presence of citric acid (CA) as acrificial agent has been investigated using TiO2-modified bamboo charcoal as photocatalysts prepared with Sol-Gel method. The influence of the catalyst dosage, Cu(II) of the initial quality concentration, photocatalytic time, catalyst roasting temperature and the solution acidity to Cu(II) removal rate has been explored. The best conditions of Cu(II)-containing waste water treatment were determined.The results show that the effect is the optimum when the pH is 7.0, the photocatalytic reaction time is more than 60min, the usage amount of catalyst is 8 g/L and the photocatalyst is calcinated for 2h at 500°C.The degradation rate of Cu(II) ion can be improved using appropriate extension reaction time method.
Rheological Properties of PAN and Silk Fibroin in Aqueous NaSCN Solutions
Authors: Wang Jian
Published: July 2012

The rheological properties of polyacrylonitrile (PAN) and silk ﬁbroin (SF) in the aqueous NaSCN Solutions were investigated in this study. The results show that the solutions possessed slightly pseudo-plastic solution properties. Their apparent viscosity increased with the increasing total polymer concentration, whereas all of these decreased with the increasing temperature. The viscosity of PAN/SF blend solutions decreased with the increase of the SF component.
Research Progress of Adsorption Characteristics of Polycarboxylate Superplasticizers and Effect on Cement Dispersion, Hydration
Authors: Bi Yao , Lei Jia Heng , Du Xiao Di
Published: July 2012

Polycarboxylate superplasticizers(PCs) were important admixtures in modern concrete preparation, and working mechanism research was paid close attention since its invention. The international research progress of adsorption characteristics of Polycarboxylate superplasticizers and effect on cement paste dispersion, hydration was introduced, appropriate analysis and discussion were made focusing on existing problems in relational researches in purpose of providing ideas for further research of cement- PCs interactions.
Transient Absorption Properties of 1, 8, 15, 22-Tetra-N-Pentyloxy Metallophthalocyanines and Metal Free Phthalocyanine
Authors: Wei Xi Ran , He Chun Ying , Chen Zhi Min , Song Wei Na , Zhang Jun , Yang Yi Xiao , Wu Yi Qun , Wang Bin
Published: July 2012

In this paper, the triplet properties of a series of 1, 8, 15, 22-tetra-n-pentyloxy metallophthalocyanines [α-MPc(OC5H11)4), M=Fe, Ni, Cu, Zn] and metal free phthalocyanine [H2Pc((OC5H11)4)] were investigated using flash photolysis technique in solutions at the concentration of 10-5mol/L. The triplet absorption curves and triplet lifetimes were acquired. ZnPc(OC5H11)4 exhibits a strong triplet absorption and has long triplet lifetime due to the d-electron and charge transfer effect.
Wet Blending of Pregelatinized Starch and Poly(butylene succinate)
Authors: Ni Hong Kai , Yang Biao , Sun Hui , Xu Guo Zhi
Published: July 2012

The biodegradable films of the blend of pregelatinized starch and poly(butylene succinate) were prepared by using mixture of water and glycerin as plasticizing agent. The mechanical properties, thermal performance of the films and molecular weight of PBS were investigated. Gel permeation chromatography (GPC) results indicate that the molecular weight of PBS has no obvious change in spite of the presence of water. Starch can be well plasticized and uniformly dispersed in PBS matrix without obvious particles and agglomeration observed. When starch content was 10 wt% of total resin, the mechanical properties of the blend film is similar to that of pure PBS. With the further increase in the starch content, the mechanical properties were reduced; the crystallization temperature of the blend increased and the crystallization time is shortened. The thermogravimetric analysis found that pregelatinized starch and PBS decomposed in their respective temperature, the thermal stability of materials decreased.
Lead(II) Adsorption by Raw and Acid-Activated Vermiculite
Authors: Xiang Wen Jun
Published: July 2012

Acid-activated vermiculite (AAV) was prepared by treating raw vermiculite (RV) at 80°C with HCl solution. The surface properties and Pb(II) adsorption characteristics of RV and AAV were studied. The specific surface area (SSA), cation exchange capacity (CEC), pH at zero point of charge (pHZPC), and surface charge at pH 5.8 of AAV were 287.62 m2/g, 24.85 cmol/kg, pH 3.06, and -0.361 mmol/g, respectively. Compared to RV, the SSA, CEC and surface charge of AAV increased, but the value of pHZPC decreased. At pH 5.8, the maximum adsorption capacities (qmax) for Pb(II) of RV and AAV were 10.72 and 18.53 mg/g, respectively. The adsorption data for Pb(II) by RV and AAV could be well fitted using Langmuir isotherm (R2 =0.990 and 0.995, respectively)
Mechanical Properties of Oxidized Zr-1Nb-0.7Sn-0.1Fe Alloy Nuclear Cladding Tubes at High Temperatures
Authors: Lee Eun Kyu , Hong Sun Ig
Published: July 2012

The ductility loss and the failure of cladding tubes due to oxidation are considered as a threat to the safety of the nuclear. In this study, oxidation behaviors and the effect of oxide layer on the mechanical properties of Zr-1Nb-0.7Sn-0.1Fe alloy cladding tubes with a lower tin content (<1 wt. %) were investigated. The drastic increase of the oxidation rate at 700oC suggests the change in the nature of the oxide layer with increase of temperature. The acceleration of the oxidation rate for Zr-1Nb-0.7Sn-0.1Fe alloy tubes at 700oC suggests the increased volume fraction of less protective porous oxide, supported by the presence of oxide cracks even before mechanical testing. The ductility increased after oxidation at 600oC, suggesting softening due to recovery and recrystallization is predominant over the ductility loss caused by oxidation. The ductility began to decrease significantly after oxidation at 700oC and cladding tubes exhibited the brittle fracture.
Thermal Properties of SMA-g-PEG as Novel Form-Stable PCMs for Thermal Energy Storage
Authors: Tang Bing Tao , Yang Zhenyu , Zhang Shu Fen
Published: July 2012

Novel polymeric form-stable phase change material (SMA-g-PEG) was synthesized by the reaction of styrene-maleic anhydride copolymer (SMA) with polyethylene glycol (PEG). The phase transition behaviors and crystalline morphology were investigated by DSC and WAXD, and thermal stability was analyzed by TGA. The results indicated that the SMA-g-PEG has suitable transition temperature, high transition enthalpy and good thermal stability. The heat storage mechanism of SMA-g-PEG is the transfer between crystalline and amorphous states of the hanging segment PEG. And SMA, serving as ‘polymeric bone’, restricts the molecular chain of the hanging segment’s free movement at high temperature, so, SMA-g-PEG can keep its solid state in the transition processing.
Hydrothermal Synthesis of Lithium Titanate as Anode Materials for Lithium-Ion Batteries and its Performance at Different Charging and Discharging Mode
Authors: Cheng Chong Ling , Wang Jie , Liu Hong Jiang , Zhang Deng Song , Shi Li Yi
Published: July 2012

Li4Ti5O12 nanoparticles were synthesized through hydrothermal method. The structure and morphology characteristics of the composite were investigated by XRD, SEM. Meanwhile, electrochemical properties were analyzed through charging-discharging test. The prepared Li4Ti5O12 nanoparticles had good rate performance and cycling performance. It exhibited discharging capacity of 136.0 mAh/g at a high rate of 10 C. It also had good performance when it charging at low rate and discharging at high rate.