Jorunal of Functional Materials

Select

Preparation, Microstructure Control and Thermoelectric Properties of One dimension Bi2Te3 Based Nano-Materials

FAN Xi-an;HONG Xiao-jie;WU Zhao-yang;ZHU Cheng-yi;LI Guang-qiang;HOU Yan-hui

. 2013, 44(03): 305-312.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Microstructure engineering of thermoelectric materials can resolve the conflicts of electrical and thermal transports. Especially, one dimension (1D) Bi2Te3 based thermoelectric nanomaterials have obvious crystal anisotropy and strong quantum confinement effect to improve the thermoelectric figure of merit and converision efficiency. As the most important low-temperature thermoelectric materials, Bi2Te3 materials have broad commercial applications in thermoelectric power generation and cooling. In this paper, the microstructure controlling methods about the morphology parameters (including diameter and length) and crystal plane preferred orientation, growth mechanism and the effect of microstructure on thermoelectric properties are. reviewed in detail in terms of the preparation technology of 1D Bi2Te3 thermoelectric nanomaterials. As a consequence, the future research in 1D Bi2Te3 based thermoelectric nanomaterials should be focused on the exploration of new 1D microstructure controlling methods, perferred orientation and assembly technology, the intrinsical relation between thermoelectric properties and microstructure, and the actual application in the thermal power generation and cooling., Microstructure engineering of thermoelectric materials can resolve the conflicts of electrical and thermal transports. Especially, one dimension (1D) Bi2Te3 based thermoelectric nanomaterials have obvious crystal anisotropy and strong quantum confinement effect to improve the thermoelectric figure of merit and converision efficiency. As the most important low-temperature thermoelectric materials, Bi2Te3 materials have broad commercial applications in thermoelectric power generation and cooling. In this paper, the microstructure controlling methods about the morphology parameters (including diameter and length) and crystal plane preferred orientation, growth mechanism and the effect of microstructure on thermoelectric properties are. reviewed in detail in terms of the preparation technology of 1D Bi2Te3 thermoelectric nanomaterials. As a consequence, the future research in 1D Bi2Te3 based thermoelectric nanomaterials should be focused on the exploration of new 1D microstructure controlling methods, perferred orientation and assembly technology, the intrinsical relation between thermoelectric properties and microstructure, and the actual application in the thermal power generation and cooling.

Select

Preparation and properties of epoxy/SiO2 nanocomposite materials by cationic photopolymerization and sol–gel process

LI Zhen-jiang;LIANG Wei;ZHANG Lin

. 2013, 44(03): 313-316.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Abstract: UV-curable epoxy/SiO2 nanocomposite materials were prepared by using tetraethyl orthosilicate (TEOS) as inorganic precursor,3-methacryloxypropyltrimethoxysilane (GPTS) as coupling agent, 1,6-hexanediol diglycidyl ether（HDGE）as polymerizable monomer and triphenylsulfonium hexafluorophosphate salt ( PI -432) as photo initiator through a dual-cure process involving cationic photopolymerization of epoxy groups and subsequent condensation of alkoxysilane groups . The structures ,thermal and optical properties of nanocomposite materials were characterized by XRD,XPS,DSC,TGA and UV/Visible spectral spectrometer. The results showed that in-situ generated nano-SiO2 dispersed uniformly in the polymer matrix and the nanocomposite materials' glass transition temperature and thermal decomposition temperature improved a lot compared with pure HDGE, on the other hand, the nanocomposite materials' optical properties is also very good.

Select

Synthesis of CuS flower-like nanospheres by simple chemical water bath method and their optical properties

LI Yuan;LI Qing;WU Hui-jie;ZHANG Jin;LIN Hua;ZHANG Yu

. 2013, 44(03): 317-321.

Abstract ( )

Download PDF ( )

Knowledge map

Save

CuS flower-like nanospheres were obtained via a simple chemical water bath method under the assistance of SDBS at 100 ℃ for 4 h. The as-prepared samples were characterized by XRD, EDX, FESEM, UV-vis and PL techniques. The results showed that the products were well crystalline and the particle size was uniform with the average diameter of 350 nm. PL spectrum indicated that the product had a strong fluorescence emission peak at 486 nm in visible light area excited by 370 nm light and exhibited a dramatic blue-shift. The surfactant SDBS plays a crucial role on the morphology and size of the products. The effects of experimental parameters on the formation of the flower-like nanospheres were explored, and a plausible three-stem mechanism was proposed to explain the formation of CuS flower-like nanospheres.

Select

Research on the drug release behaviors and mechanisms of Fe3O4/(PNIPAAm-co-Am) composite microspheres

AI Fan-rong;ZHANG Shuo

. 2013, 44(03): 322-325.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Fe3O4/P(NIPAAm-co-Am) magnetic thermosensitive composite microspheres were prepared by emulsifier free polymerization. Measurement of DLS was carried to investigate the thermosensitive properties. The drug release behaviors were investigated at different temperature or under alternating magnetic field. Results show the LCST of the composite microspheres is about about 40℃. Furthermore, the controlled drug release behaviors of the composite particles show an intermittent alternating magnetic can improve the accumulate drug release, indicating the composite particles posses a potential application on hyperthermia combined with the chemotherapy treatment of cancer.

Select

Research and Application on PP/SEBS Elastomer with high Gloss

Yang Fan-wen CHEN Xiao-ming;XU Ke-mou

. 2013, 44(03): 326-328.

Abstract ( )

Download PDF ( )

Knowledge map

Save

The effect of YY-503 modifier content on properties of PP/SEBS elastomer was studied. With increase of YY-503 content, the tensile strength, elongation at break, MI and gloss increased, which showed that the YY-503 could improve properties of PP/SEBS elastomer. At YY-503 low content, tear strength increased with increase of YY-503 content. However, it decreased when YY-503 content was more than 2% because lubricating effect had bad effect on tear strength when it exceeded saturated limit content for surface modification of filler. YY-503 had good effect on melt flow index (MI) and surface gloss. When the YY-503 content was 2%, the MI increased about 1 times and surface gloss increased by about 40% to 60.5, which could meet the high gloss appearance requirements of plastic parts for medical devices.

Select

Study of the Synthesis of Anatase TiO2 Sol via Microwave Treatment and its Photocatalytic Performance

ZHOU Jian-ping;JING Meng-meng;YANG Yi;LIU Zhi-lei

. 2013, 44(03): 329-332.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Titania sol was prepared firstly by using Ti(OC4H9)4 as the precursor , then anatase TiO2 sol was synthesized via microwave processing. The as-prepared sol was characterized by XPS、XRD and UV-vis and its photocatalytic performance was investigated. The results show that after treating by microwave for 4 hours, the dried sol exhibits obvious anatase characteristic peak in XRD spectrum; XPS analysis indicates that titanium atoms exist in form of +4 and O element exists in two forms, one is O-H the other is O-Ti; The sol has strong photocatalytic ability toward methyl orange under UV illumination. Decoloring efficiency could be up to 94.7% with only 15 min of UV source lighting. The fluorine carbon coating was modified by the TiO2 sol ，the contact angle with water was reduced from 82°to 13°in the ultraviolet radiation for 24h .Such a sol exhibits immense application potential in self-cleaning coatings.

Select

Preparation of SiC whisker with rice straw

LI Sheng-jie;LIU Guo-jun;CHEN Hua;JIA Su-qiu

. 2013, 44(03): 333-336.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Abstract：SiC whiskers were prepared with waste rice straw between 1300℃ and 1400℃ at Ar atmosphere. The effect of temperature, time and catalyst on SiC whiskers formation was measured. The results show that formation of SiC whiskers was at 1350℃. The heating method was first heating higher than the keeping temperature and quickly dropping to the keeping time and keeping for 2 hours. SiC whiskers mainly consisted of β-SiC and a little α-SiC also was prepared. SiC whiskers were bamboo-like and their diameters were among 10 to 200nm and their length diameter ratio was larger than 10. Much SiC whiskers were formed with NaF and H3BO3 as catalysts. Vapor-Liquid-Solid (VLS) mechanism was discussed. Preparation of SiC whiskers with waste rice straw was a new method for application of waste rice straw．

Select

Study on the SMC molding technology and absorbing properties of new-type absorbing composite

LI Xiao-min;ZHU Zheng-hou;ZHENG Xia-lian;LIU Ji-lei;HUO Jia

. 2013, 44(03): 337-339.

Abstract ( )

Download PDF ( )

Knowledge map

Save

In the paper, the absorbing composite panels with excellent properties were prepared successfully using E-51 epoxy resin as matrix and Fe78Si13B9 amorphous powder as absorbing agent. In addition, the molding technology and performance index were studied systematically. The results show that the absorbing composite panel presents regular layer structures and the content of absorbing agent in every layer is distributed evenly. Meanwhile, the composite has good mechanical properties with the tensile strength 128.03MPa and bending strength 253.04MPa. Furthermore, the absorbing properties with different mass ratios of absorbing agent and epoxy resin were measured by vector network analyzer. It is shown that the reflection peaks shift gradually towards the low frequency. When the mass ratio of absorbing agent and epoxy resin is 6:1, the absorbing properties demonstrate excellent in a large wide frequency range from 2.7GHz to 18GHz with the reflection values less than -4dB, which provides a valuable reference for the next absorbing compositions design.

Select

Microstructures and mechanical properties of in situ TiB2/7055 composites synthesized by pulsed magnetic field

ZHONG Long-hua;ZHAO Yu-tao;ZHANG Song-li;CHEN Shuai;WU Jiang-jing;JIAO Lei

. 2013, 44(03): 340-344.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Under the pulsed magnetic field, in situ TiB2/7055 composites are successfully synthesized by direct melt reaction from 7055-(Al-3%B)-Ti system. The phase compositions and the microstructures of the composites are investigated by XRD, OM and SEM, and the tensile properties are tested by electronic tensile testing machine. The results indicate that the reaction process is faster and fully with pulsed magnetic field assistance, and the distributions of particles are uniform. The morphologies of the TiB2 particles are mainly with hexagonal-shape or nearly polygon, and the size is about 600 nm. The average grain sizes of α-Al are decreased to 10~20 μm, and the array of the second phases are changed from continuous net-shape to discontinuous shape. The tensile strengths of the composites are enhanced from 310 MPa to 330 MPa, and the elongations are increased from 7.5 % to 8.0 %.

Select

Zinc Doped Cobalt Ferrite: Hard Magnetic → Soft Magnetic

LI Shi-rong;REN Yong;WANG Gai-hua;LV Shi-ya;DAI Bo

. 2013, 44(03): 345-348.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Co1-xZnxFe2O4 doped with different amount of zinc were prepared by the chemical co-precipitation method, and the influences of doped zinc on structure and magnetic properties of cobalt ferrite were studied. The average grain size of Co0.7Zn0.3Fe2O4 was 8.566 nm at the 400 ℃ for 2 h, which was calculated from X-ray diffraction data according to Scherrer’s formula. Static magnetism of Co1-xZnxFe2O4 was investigated by vibrating sample magnetometer. Great changes have been found in magnetic properties with the degree of zinc substitution: the value of saturation magnetization increased with increasing of Zn2+ ion contents, while the coercive force decreased. When x=0.3, the coercive force is only 17 Oe and the saturation magnetization is 42 emu/g, which realized transition of CoFe2O4 from hard magnetic to soft magnetic, so it can be considered as potential soft magnetic materials at high frequency.

Select

The Relationship Between Aramid Paper Honeycomb Mechanical Properties and Paper Performance

WANG Hou-lin;WANG Yi;YAO Yun-zhen;HU Jian;YANG Jin

. 2013, 44(03): 349-352.

Abstract ( )

Download PDF ( )

Knowledge map

Save

In this paper, the relationship between the modulus of aramid paper honeycomb core and the performance of cell wall material was studied, and the mechanical models put forward by Kelsey were verified. The results show that the product of Young’s Modulus and thickness of the cell wall is the key performance parameter that effect the stabilized compressive modulus of aramid paper honeycomb, increased with phenolic resin content, E is also increased with phenolic resin content .And the product of shear modulus and thickness of the cell wall is the key performance parameter that effect the shear modulus of aramid paper honeycomb, increased with phenolic resin content, G also increased with phenolic resin content.

Select

Hole Doping Effects on the Transport Properties of Sr2FeMoO6

HU Yan-chun;YANG Ju-bao;HU Hua-jie;CHEN Chen;ZHANG Ke-lei;YANG Hai-gang;MA heng

. 2013, 44(03): 353-356.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Polycrystalline samples of Sr2-xKxFeMoO6 (x=0.00, 0.01, 0.02, 0.03, 0.04) were prepared by standard solid-state reaction. By measuring the electrical resistivity, we were able to identify the semiconductor–metal transition temperature, which was found to decrease from 170K to 72K with increasing x. The scanning electron microscope (SEM) result showed that the hole doping remarkably decreased the grain size, enhancing the degree of crystallinity. All these observations can be understood based on the interplay among size change in grain boundary, the anti-site defect concentration and the hole doping.

Select

Further Research on The Humidity Sensing Properties of ZnCr2O4-V2O5-Li2O-ZnO

XU Tian-hua;ZHAO Yue;SUN bin;FU Heng-lei;SONG Wei

. 2013, 44(03): 357-359.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Select

Study on gas-sensing properties of Ni-LaFeO3 prepared by microwave chemical synthesis process

ZHANG Ji;FAN Wei-tao;ZHU Zhong-qi;LIU Qing-ju

. 2013, 44(03): 360-362.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Abstract: Ni-LaFeO3 powder was prepared by the method of microwave chemical synthesis. The crystal structure and morphologies of Ni-LaFeO3 were characterized. The results show that the Ni-LaFeO3 was pure perovskite structure, the dispersive of Ni-LaFeO3 particle is uniform and the particle size is about 187nm. The sensitivity and selectivity of LaFe0.9Ni0.1O3 for 500ppm formaldehyde are good, the response and recovery time are about 20s and 30s, respectively.

Select

Effects of film thickness on the tunneling electroresistance of PZT/STO ferroelectric capacitors

WANG Ying-long;LIU Lin;ZHANG Peng-cheng;LIANG Wei-hua;DING Xue-cheng;CHU Li-zhi;DENG Ze-chao

. 2013, 44(03): 363-366.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Combining Landau-Devonshire free energy theory and lattice model, the effects of the thickness of PZT and STO in the PbZr1-xTixO3 (PZT)/SrTiO3 (STO) composite films on the intensity of polarization, conductance and tunneling electroresistance in the ferroelectric tunnel junction have been discussed. The results show that as the number of layers increases, the intensity of polarization increases. And average polarization strength increases with the increasing PZT thickness, but it decreases with increasing STO thickness. Conductance decrease and tunneling electroresistance increases with the increasing PZT and STO thickness. When the change of film thickness is the same, PZT cause a bigger change of conductance, yet a less change of tunneling electroresistance. Considering the effects of film area, intensity of polarization, conductance and tunneling electroresistance decrease when the film area changes from infinity into finite.

Select

Study on co-firing behavior of cordierite ceramic with Bi2O3 addition

WANG Shao-hong;ZHOU Dan;HOU Chao-xia;WANG Mei-han;HU Xiao-dan;NIU Chang-lei

. 2013, 44(03): 367-370.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Select

Effect of (NH4)2HPO4 impregnation on the structure and performance of carbon cloth

LI Ya-dong;ZHANG Xue-jun;TIAN Yan-hong;WANG Su-qing;LI Chen;SHEN Zeng-min

. 2013, 44(03): 371-375.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Abstract：Man-made cotton cloth was used as raw material to prepare flexible carbon cloth. After impregnation in (NH4)2HPO4 solution, cotton cloth was carbonized and then graphitized. The influence of impregnation solution on the carbonization of cotton cloth was investigated. The change pattern of yield, electrical resistivity, tensile strength and elongation at break was studied. It was found that after impregnation in (NH4)2HPO4, the yield of carbon cloth was raised from 11.3% to 31.3%. The electrical resistivity dropped remarkably, which was 0.068Ω?cm after graphitization. The elongation at break was 14.7%. The prepared carbon cloth at the same time had relatively good permeability and strength, which was appealing for application in gas diffusion layer materials of fuel cell.

Select

Adsorption of metyl orange from aqueous solutions onto protonated cross-linked chitosan

YANG Bing-chao;LIU Qian;HUO Jie;HUANG Rui-hua

. 2013, 44(03): 376-379.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Select

Study on the activation characteristics and hydriding/dehydriding kinetics properties of La0.67Mg0.33Ni3 alloy

LIU Jing;LI Qian

. 2013, 44(03): 380-383.

Abstract ( )

Download PDF ( )

Knowledge map

Save

By taking the La0.67Mg0.33Ni3 alloys prepared assisted by a high magnetic field as the research object, the phase structure, micro-morphology, activation characteristics and hydriding/dehydriding kinetics properties were investigated through XRD, SEM and constant volume method. The results show that the main phase of alloys produced by MASS is PuNi3 type (La, Mg)Ni3. The alloy particle exhibits a rough and porous surface. The sample prepared under 1 T magnetic field can be activated after three hydriding/dehydriding cycles and the maximum hydriding capacity is 1.47 wt.%. The kinetic analysis indicates that the optimal sample which prepared under 1 T magnetic field can absorb hydrogen saturatedly at room temperature within 50 s under 1.0 MPa H2 and finished hydrogen desorption at 333 K within 400 s under 0.001 MPa H2. However, the reversible hydrogen desorption amount is relatively low.

Select

Effect of Ag on properties of Sn-0.7Cu-0.2Ni alloy solder

CHENG Yan-kui;LI Liang-feng;XU Guang-liang

. 2013, 44(03): 384-387.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Adding a small of Ag in Sn-0.7Cu-0.2Ni solder alloy, the melting temperature, thermal expansion coefficient, wetting properties and the corrosion resistant of Sn-0.7Cu-0.2Ni -xAg were measured. The results show that the trace amount of Ag can decrease the melting point of Sn-0.7Cu-0.2Ni alloy solder,but the melting range rasies as Ag was added. When the content of Ag is 0.3wt%, the melting point of Sn-Cu-Ni alloy solder is 224.07℃ and the melting range is 6.1℃. The coefficient of thermal expansion(CTE) increases with the content of Ag increasing. CTE of Sn-0.7Cu-0.2Ni-0.3Ag is 18.4×10-6/℃ from room temperature to 100℃ . Meanwhile, the addition content of Ag can improve corrosion resistance of solder in HCl solution and effectively increase the spreading area of solder on the Cu substrate.

Select

Study on heavy metal ion Zn2+ mineralized by Phosphate ore implication of bacteria

WANG Ming-ming;QIAN Chun-xiang

. 2013, 44(03): 393-395.

Abstract ( )

Download PDF ( )

Knowledge map

Save

The selected strain called strain A, and it is a kind of phosphate ore implication of bacteria. The heavy metal ions ( Zn2+ for example) were mineralized as stable cacium phosphate precipitation by the PO43- decompounded by the enzyme effect of strain A induced by the substrate. Qualitative analysis shows the mineralization product in neutral condition by SEM and XRD. Quantitative analysis proves the mineralization products in different pH, combined with XRD analysis. Through the experiment can be found that strain A’s application in mineralizing metal ions is good in effect, environmental friendly, simple in process, and is in prospect of actual pollution repair.

Select

Research on synthesis and thermal properties of hexakis (4-formacylphenoxy) cyclotriphosphazene

Bao Dong-mei;LIU Ji-ping

. 2013, 44(03): 396-400.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Hexakis (4-formacylphenoxy) cyclotriphosphazene(HAPCP) is an important efficient halogen free flame retardant and fine chemical intermediate and it has attracted significant attention because of its excellent heat-resistance and flame-resistance. In the study, HAPCP was prepared via the reaction of hexachlorocyclotriphosphazene(HCCP) and 4-hydroxybenzaldehyde, and characterized by means of infrared spectrometer (IR), nuclear magnetic resonance (NMR), elemental analysis, differential scanning calorimetry(DSC) and thermogravimetry(TG). The influences of the reactive solvent, type and particle size of deacid reagent, molar ratio of p-hydroxybenzaldehyde to HCCP, reaction time(t) and reaction temperature(T) on the yield were investigated. The results showed when n(p-hydroxybenzaldehyde):n(HCCP)=7.2:1,T= 65℃, t= 24 h, tetrahydrofuran as solvent and anhydrous sodium carbonate as deacid reagent, the yield of HAPCP was the highest and amounted up to 92.5%.Thermal analysis results showed that the onset decomposition temperature of HAPCP was 270℃, and the carbon yield at 800℃ was still up to 78.5%.Therefore, HAPCP is an inorganic-organic heterocyclic compound with perfect heat-resistance and thermal stability, and it is a promising candidate applied in insulating materials and flame retardant materials.

Select

Hydrophobic properties of Wooden-base photochromic functional materials

LI Guo-liang;JIA Zhen;LI Jian

. 2013, 44(03): 401-404.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Wooden-base photochromic functional materials expanded the application fields and development directions of wood materials. The photochromic Polyvinyl alcohol（PVC）film overlapped on the wood surface was easy to hydrolysis, so the research on its hydrophobic properties was imminent. This paper discussed these effects of the toluene diisocyanate (TDI) content, polyols kinds and content, modified temperatures and modified time on hydrophobic properties of the sample surface. It was concluded that contact angle of the sample surface by the two footwork modified was 133°。The hydrophobic properties of Wooden-base photochromic functional materials were increased, which expanded the scope of application of Wooden-base photochromic functional materials surface.

Select

The multisale model of the failure in SiC/IMI834 composites

YUAN Mei-ni;YANG Yan-qing;HUANG Bin;LI Mao-hua

. 2013, 44(03): 405-409.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Green’s function and finite element methods were used to model the tensile test of metal matrix composites，and research the micro-stress distribution, macro-mechanical properties, and fiber failure in metal matrix composites. Finite element method was used to calculate the micro-stress field and stress transfer concentration factor for Green’s function. Green’s function was used to simulate the macroscopic failure process and mechanical properties in metal matrix composites. The results are shown that the stress recovery length in failure fiber depends on material properties, but is independent of the applied load. The axial stress in fiber along the failure surface diminishes as the distance from the failure fiber increases. However, the axial stress in matrix along the failure surface decreases as the distance from the failure fiber decreases. The macroscopic failure strain in SiC/IMI834 composites increases with the increasing of fiber volume fraction. However, the initial failure fiber in SiC/IMI834 composites has nothing to do with the fiber volume fraction.

Select

Synthesis and characterization of MgAlCe layered double hydroxide

SHEN Gen-li;ZHANG Dang-wen;WANG Qi;WANG Zhen;CHEN Yun-fa

. 2013, 44(03): 410-412.

Abstract ( )

Download PDF ( )

Knowledge map

Save

MgAlCe layered double hydroxide was synthesized by co-precipitation and hydrothermal method. The effects of the ratio of Al/Ce, reaction temperature, pH were studied. The products were characterized by XRD, TG/DTG, SEM and TEM. The results showed that the best ratio of Al/Ce was 16:1 and the best pH was 8.1 for co-precipitation. After a 140 ℃，10 h hydrothermal treating, MgAlCe layered double hydroxide with good crystal structure was prepared. According to TG/DTG, it had good thermal stability. Hydroxyl and nitrate Ion in layers were lost between 300 oC and 500 oC. It had good potential of fire retardance.

Select

Effect of manufacture conditions and electrochemical properties of conductive sulfonate silicone polyether

LENG Cui-ting;LI Xiao-rui;FEI Gui-qiang;WANG Hai-hua;HU Su-juan

. 2013, 44(03): 413-416.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Select

Nano Black High Near-infrared Reflectance Ceramic Pigments Synthesized by Sol-gel Method

ZHANG Xiao-yu;ZHANG Yu-jun;GONG Hong-yu;WANG Cui-ling;ZHAO Xin-qiao;ZHU Hong-li;XIONG Tian-nong

. 2013, 44(03): 417-420.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Nano black high near-infrared (NIR) reflectance ceramic pigments were prepared with ferric nitrate, chromium nitrate, citric acid, and ethylene glycol by sol-gel method. The effects of different molar ratio of Fe and Cr, hydrolysis temperature, the pH of the solution, concentration of metal ions and calcination temperature were investigated. The results show that the crystalline phase of the as-prepared pigments is Cr1.3Fe0.7O3 with average NIR reflectance about 77.58% in 700nm~2500nm wavelength range when Fe/Cr molar ratio is 0.50, hydrolysis temperature is 70℃, pH value is 3~4, metal ion concentration is 2.5mol/L~3.5mol/L, calcination temperature is 900℃.

Select

Preparation and the performance of electromagnetic parameters of needle-shaped zinc oxide whiskers

LU Hui-fang;ZHU Zheng-hou

. 2013, 44(03): 421-423.

Abstract ( )

Download PDF ( )

Knowledge map

Save

ZnO whiskers were prepared by heated in a muffle furnace in gradient with mixture of zinc and carbon powders.The phase structure, morphology and size of ZnO whiskers were characterized by X-ray diffraction and scanning electron microscopy. Also analyzed the absorbing properties of the obtained ZnO whiskers. The results show that the zinc oxide whisker is of high purity and high crystallinity. ZnO whiskers arranged in dense, and a needle structure. The diameter of ZnO whiskers is 20~50 μm, length of it is more than 700 μm, and its length-diameter ratio is greater than 14, in line with whiskers standards. With the quality of ultra-fine iron powder and ZnO whiskers ratio of 4 and 1, the composite electromagnetic loss is similar to each other. It shows that by adding the change of ZnO whiskers has no greater impact on the microwave absorbing properties.

Select

Preparation of High Dispersion Nano Magnesium Hydroxide by Changing Temperature Method

FAN Tian-bo;NAN He;YAO Jian-ping;LI Xue;ZHANG Li;LIU Yun-yi

. 2013, 44(03): 424-427.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Abstract: High dispersion nano magnesium hydroxide were prepared via controlling the supersaturation of reaction system by changing reaction temperature using refined magnesium chloride solution obtained by the reaction of light calcined powder with ammonium chloride as raw material and gaseous ammonia as precipitant. The products were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and laser particle analyzer. The morphology and particle size of magnesium hydroxide products prepared by isothermal method were compared with the products prepared by changing temperature method, and based on the variation process of the OH- concentration with reaction temperature, the mechanism of the preparation process of high dispersion nano magnesium hydroxide via changing temperature method was analyzed and discussed.

Select

Synthetize anionic polyurethane/acrylate microemulsion prepared by in-situ surfactant-free emulsion polymerization and its waterproof for paper

ZOU Jing;SHEN Yi-ding;WANG Hai-hua;FEI Gui-qiang

. 2013, 44(03): 428-431.

Abstract ( )

Download PDF ( )

Knowledge map

Save

A facile route to prepare polyurethane/polyacrlate microemulsion (PUA) by in-situ surfactant-free emulsion polymerization was proposed, and PUA were synthesized by reacting isophorone diamine (IPDI), polycaprolactonediols (PCL) , dimenthylol butanoic acid(DMBA), hydroxyethyl acrylate(HEA), styrene(St) and butyl acryolate(BA). The factors affecting its synthetic condition were discussed, and the synthetic process was optimized. The results show that the microemulsions owns excellent sizing property when w（DMBA）=8%，w（HEA）=4%, n（NCO）/n（OH）=1.6, w（PU）/w（PA）=1:1 and with 7% polymer microemulsion addition. The waterproof properties of paper with treatment increased by 73%. Finally , the polymer was characterized with Fourier transform infrared spectra(FT-IR) , thermogravimetry(TGA) , scanning electron microscope (SEM) , and dynamic contact angle . FT- IR and TGA demonstrated the PUA was obtained, and PUA has good thermal stability. SEM photographs further certified that the cracks and defects on the fibers were apparently reduced. Dynamic contact angle measurement confirmed the water contact angle was 118°and the angle almost keep unchanged within 300 s.

Select

Preparation and analysis of high color rendering index white LED

HU Chang-qi;ZHANG Fang-hui

. 2013, 44(03): 432-434.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Abstract: The spectrum of white LED was studied and the color rendering index was improved respectively. Here, the MPPV was coated to the LED chips, then the YAG phosphor on top of MPPV. The weight ratio of MPVV was 0%、1%、4%、6% relative to YAG respectively. From the results of ratio increasing, we found that the peak increased significant in the region of red light. The red region appeared radiation peak obviously and the color rendering index reached 88 when the ratio was 4%. Moreover, we studied and analyzed why MPPV can improve the CRI of White LED significantly based on the standard calculation method of CRI, by contrasting to the eight standard test color and the corresponding special color rendering index.

Select

Preparation and drug release performance of thermosensitive SPPCL-PNIPAAm copolymeric micelles used as anti-cancer drug carrier

WANG Hao;ZHOU Zhi-ping;DAI Xiao-hui

. 2013, 44(03): 435-441.

Abstract ( )

Download PDF ( )

Knowledge map

Save

The thermosensitive copolymer poly(e-caprolactone)-b-poly(N-isopropylacrylamide) was synthesized by reversible addition-fragmentation chain transfer polymerization (RAFT) using a tetra-hydroxyethyl terminated porphyrin as a core initiator. The copolymer was characterized by fourier-transform infrared spectroscopy, 1H NMR, gel permeation chromatography, transmission electron microscopy, molecule fluorescence, UV–vis measurement, size distribution measurement. With Paclitaxel as model drug, the drug release behavior of the copolymeric micelles was studied. It was found that the sizes of copolymeric micelles are around 100 nm after self-assembly. The Paclitaxel loaded micelles are stable, in the release medium of 38℃ the release of Paclitaxel was much quicker than that at 15℃. Therefore, the release of Paclitaxel from the copolymeric micelles could be controlled by changing temperature. The SPPCL-PNIPAAm copolymeric micelles has a potential application in drug release.

Select

Effect of annealing on characteristics of amorphous InGaZnO thin film transistors fabricated by sol-gel technical

LI Qian;LI Xi-feng;ZHANG Jian-hua

. 2013, 44(03): 442-445.

Abstract ( )

Download PDF ( )

Knowledge map

Save

The amorphous InGaZnO (a-IGZO) thin films were fabricated by sol-gel technology. The IGZO sol-gel was prepared by dissolving indium nitrate hydrate, zinc acetate dehydrate and gallium nitrate with a molar ratio of 1:1:2 in methanol at room temperature. The concentration of the metal ions was maintained at 0.3 mol/L. The mixed sol was then stirred continuously at 70 oC for 1h using a water bath until a clear and transparent homogeneous sol was formed. The a-IGZO thin film was spinning coated on the chip with a speed of 2000 rmp/min. Then the film was hearted on hot plate at 150 oC for 15 min and annealed at 350 oC for 1 hour in air and vacuum atmosphere. As a result, air annealing improved the transmittance of the a-IGZO thin film, while the vacuum atmosphere decreased the transmittance. The optical transmittance of the a-IGZO thin films annealed in air can reach to average 80%. All the thin films had smooth surface and the roughness RMS is less than 0.6nm. The a-IGZO films annealed in vacuum atmosphere’s roughness is bigger than that in air. The TFT’s transfer characteristic is improved in vacuum atmosphere. The off current of the a-IGZO TFT annealed in vacuum atmosphere was 10-11A, and the Ion/Ioff is 104.

Select

Preparation and Characterization of Functional Humidity-Controlling Materials

ZHANG Nan;FANG Shu-ying;XIA Wei;ZHANG Yu-long;LI Jia-chang;ZHANG Wen-qing

. 2013, 44(03): 446-450.

Abstract ( )

Download PDF ( )

Knowledge map

Save

Humidity-controlling material was prepared with mineral salt, pore-forming agent (NH4HCO3) and sodium carboxymethyl cellulose (CMC) as the matrix material. Factors influencing performance of humidity-controlling material have been investigated. The structure and performance of the materials were characterized by means of analytical methods, such as FT-IR and SEM. The results indicated that the humidity-controlling material had great hygroscopicity and moisture capacity. Hygroscopic capacity of the humidity-controlling material could reach 132%、55%、30% under different humidity (80%、60%、40% RH) respectively when the material was prepared with CMC, LiCl and NH4HCO3 in the ratio of 6:3:4 in mass. Its also had great moisture capacity.

Select

Influence of Wall Texture on Slip Effect of Magnetorheological Fluids

CHEN Fei;HOU You-fu;TIAN Zu-zhi

. 2013, 44(03): 451-454.

Abstract ( )

Download PDF ( )

Knowledge map

Save

To obtain the wall slip effect of magnetorheological fluids, the magnetorheological transmission properties test-bed was established, the influence rules of groove shapes, groove densities, groove depths, texture types of wall were researched respectively, the results indicate that wall slip intensity has relationship with surface textures of disk, of which the influence of groove shape of disk is indistinctive, and the triangular section shape is slightly better than rectangular; the increase of groove density can improve the capacity of torque transmitted, and the groove depth has a optimized value range from 0~0.5mm, the wall texture slip intensity range from small to big is radialized wall, potholed wall, smooth wall and annular wall, the appearance of wall texture can improve the wall slip intensity about 10%.

Please choose a citation manager

Content to export

15 February 2013, Volume 44 Issue 03