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A new way to synthesize ZnS nanoparticles

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Chinese Chemical Letters 2007年第4期18卷 483-486页

作者： Heng Zhi Zeng ke qiang qiu Yuan Yuan Du Wen Zhang Li College of Chemistry and Chemical Engineering Central South University Changsha 410083 China

ZnS nanoparticles were prepared with normal ZnO and Na2S by solid-liquid chemical reaction under ultrasonic condition and characterized by XRD, TEM, SEM, IR and TG-DTG. The results showed that these particles were good crystal cubic zinc blended with average size of 50 nm, possess good IR transmittance in the range of 400-4000 cm and good thermal stability.

关键词： . Solid-liquid chemical reaction Nano-ZnS Crystal

Formation and thermal stability of connected hard skeleton structure in ATX525 cast alloys

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China Foundry 2015年第6期12卷 412-417页

作者： ke-qiang qiu Hui-han Zhang Yan Re Ying-lei Ren Rong-de Li School of Materials Science and Engineering Shenyang University of Technology

The formation and the thermal stability of a connected hard skeleton structure(CHSS) in the matrix of Mg-5Al-2Sn-5Ca(ATX525) alloy were investigated by using X-ray diffractometer, scanning electron microscopy, differential scanning calorimeter, creep tester and isothermal treatment method. The results indicated that the CHSS composed of Mg2(Al,Ca) and Al2 Ca intermetallics was formed into a typical eutectic structure and no obvious change occurred when the samples were isothermally treated at 250 °C for 96 h and 350 °C for 72 h, respectively. It became a chained structure when isothermally treated at 450 °C for 48 h. The dissolution and reconstruction processes, however, were observed for the CHSS when the processing temperature was up to 550 °C. The creep life at the stress-temperature condition of 50MPa/200°C for the alloy treated at 450 °C for 48 h was as high as 510 h, and the strain at creep time of 100 h was as low as 0.03%, which indicated that the present alloy has not only a good thermal stability, but also a better heat resistance.

关键词： Mg cast alloy connected hard skeleton structure isothermal treatment thermal stability heat resistance

Effect of infiltrating time on interfacial reaction and properties of tungsten particles reinforced Zr-based bulk metallic glass composites

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China Foundry 2020年第4期17卷 253-259页

作者： Qing-chun Xiang Zhi-bo Feng Wei Zhang Hong-ding Wang Ying-lei Ren ke-qiang qiu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

The tungsten particles reinforced Zr41.2Ti13.8Cu12.5Ni10Be22.5 (Vit 1 alloy) bulk metallic glass composites (BMGCs) were prepared by the melt infiltrating casting method with the infiltrating time of 1, 5 and 10 min, respectively. The changes of interfacial reaction and compression properties of the bulk metallic glass composites with different infiltrating times were studied. Results show that with the increase of infiltrating time, tiny nanocrystals are generated at the interfacial boundary of tungsten particles and the amorphous matrix, and the size of tiny crystals increases with the infiltrating time. When the infiltrating time is 10 min, polygonal crystals with a larger size are also generated within the amorphous matrix. The compressive strength of the composites also increases with the infiltrating time. When the infiltrating time is 10 min, the compressive strength of the composite reaches 2,030 MPa and the compression strain is 44%. The fracture morphology of the composite materials is in a vein-like pattern and the melting phenomenon is found on the fracture surface. In addition, the density of the shear bands during the compressive tests of the composite materials increases with the infiltrating time.

关键词： Zr-based metallic glass infiltrating time interfacial reaction shear bands compressive strength

Effect of melt cooling rate on glass transition kinetics and structural relaxation of Vit1 metallic glass

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China Foundry 2021年第2期18卷 118-123页

作者： Wei Zhang Qing-chun Xiang Ying-dong Qu Qing-feng Li Ying-lei Ren ke-qiang qiu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

The thin ribbons and the bulk cylindrical rods with diameters of 2 mm and 10 mm of the Vit1 metallic glass(MG)were prepared by the single roller melt spinning method and the copper mold injection casting method,*** cooling rates of the samples during melt solidification were *** glass transition behaviors of three groups of MG samples with different solidification cooling rates were studied by differential scanning calorimetry(DSC)at different heating *** effects of melt cooling rate on the glass transition kinetic parameters such as apparent activation energy(E)and fragility parameter(m)of the Vit1 MG were studied using the Kissinger and the Vogel-Fulcher-Tammann(VFT)***,the structural relaxation enthalpy(ΔHrel)of three groups of MG samples was quantitatively analyzed by DSC through multi-step temperature rise and fall *** show that the melt cooling rate(R)has a significant effect on the glass transition kinetics and the structural relaxation of the Vit1 *** R decreases in the order of magnitude,the glass transition temperature(Tg),E,m,andΔHrel of the Vit1 MG gradually ***,in the range of the experimental cooling rates,E,m,andΔHrel all have an approximately linear relationship with lgR.

关键词： glass transition structural relaxation apparent activation energy fragility parameter cooling rate Vit1 metallic glass

Glass formation in Fe-Cr-Zr-B-Mo alloys by tuning Nb addition

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China Foundry 2021年第5期18卷 450-456页

作者： Cong-ran Fu Wei Zhang Qing-chun Xiang Ying-dong Qu Ying-lei Ren Bo Yu ke-qiang qiu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Shenyang Research Institute of Foundry Co.Ltd. Shenyang 110022China

Fe-based bulk metallic glasses(BMGs)with high boron content have potential application as a coating material used in the framework for storing spent nuclear fuels to support their safe long-term *** high glass forming ability(GFA)and large supercooled liquid region are therefore required for such Fe-based BMGs in either the glassy powder fabrication or the subsequent coating *** order to meet these requirements,the influence of Nb content on the GFA of Fe_(57)Cr_(10)Zr_(8)B_(18)Mo_(7-x)Nb_(x)(x=1-5,at.%)alloys was investigated,as Nb has positive roles in GFA and thermal stability of *** results indicate that a fully amorphous phase in the as-cast samples with 3 mm in diameter is obtained for both the Fe_(57)Cr_(10)Zr_(8)B_(18)Mo_(5)Nb_(2) and Fe_(57)Cr_(10)Zr_(8)B_(18)Mo_(4)Nb_(3) *** corresponding supercooled liquid regions of the two BMGs are 78 K and 71 K,*** mechanism for improving their GFA was analyzed based on the principle of metal solidification,the parameters for glass formation and thermal properties of the *** compression strength and Vicker’s hardness of the two BMGs are 1,950 MPa and 1,310 HV,2,062 MPa and 1,180 HV,*** developed BMGs with high B content,good GFA,and very high hardness can be used as coating materials to the framework for spent nuclear fuels.

关键词： amorphous microstructure Nb glass-forming ability coating material

Fabrication of large UV transmission blazed gratings for slitless spectral sky survey

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Research in Astronomy and Astrophysics 2021年第12期21卷 396-404页

作者： Zhi-Wen Chen Mao-Qi Cai ke-qiang qiu Ya-Nan Wang Huo-Yao Chen Zheng-Kun Liu Ying Liu Yi-Lin Hong Hai-Jiao Jiang Zhong-Wen Hu National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China key Laboratory of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China

Slitless spectral sky survey is a critical direction of international astronomical *** with ground-based sky survey,space-based sky survey can achieve full-band observation,and its imaging quality and resolution capability are restricted by the efficiency and size of dispersive *** blazed gratings are often used as the dispersive elements in the UV *** interference lithography produces the photoresist mask of a grating,and the ion beam etching vertically transfers the pattern to the substrate to form the SiO_2 mask of a *** reduce the effect of ion beam divergence on the uniformity of the groove shape,the grating mask is etched tilted by the ion beam passing through a narrow slit to obtain a blazed grating with consistent structural ***,twodimensional scanning of the sample stage enables the etching of large-size samples.A UV transmission blazed grating with a linear density of 333 lines mm^(-1),a blazing angle of 11.8°,and a dimension of 99.2 mm×60.0 mm×6.0 mm was successfully fabricated with an average diffraction efficiency of 66%,a PV diffraction wavefront of 0.169λ(λ=632.8 nm)and low stray light.

关键词： instrumentation:spectrographs methods:data analysis techniques:interferometric

Degradation efficiency of Mg_(65)Cu_(25-x)Ag_(x)Y_(10) nanoporous dealloyed ribbons on pesticide wastewater

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Transactions of Nonferrous Metals Society of China 2022年第5期32卷 1472-1484页

作者： Qing XIA Shi-yao HE Wei ZHANG Qing-chun XIANG Ying-dong QU Ying-lei REN ke-qiang qiu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

Dealloyed ribbons with a layer of networked nanoporous structure of different pore sizes were fabricated by dealloying the as-spun Mg_(65)Cu_(25-x)Ag_(x)Y_(10)(x=0,5,10,at.%)ribbons in dilute H_(2)SO_(4) solution in order to enhance the degradation efficiency of pesticide *** to the as-spun ribbons,it is found that the dealloyed ribbons with the networked nanoporous structure exhibit higher degradation efficiency due to their large specific surface areas and enough active sites for the degradation *** the average pore sizes of the nanoporous structure and the degradation efficiency of the pesticide wastewater increase with the increase of Ag addition in the dealloyed *** maximum degradation efficiency up to 95.8%is obtained for the Mg_(65)Cu_(15)Ag_(10)Y_(10)dealloyed ribbon under the optimal conditions of pH being 3,the initial cis-cypermethrin concentration being 500 mg/L,and the dosage of dealloyed ribbon being 1.33 g/L.

关键词： networked nanoporous structure MgCu-based amorphous ribbon dealloying cis-cypermethrin wastewater degradation efficiency

Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 246-257页

作者： ZHANG Jian NIE Wei HUANG Jin ZHU ke LIU Ruxia ZHANG Ruizhi LUO Guoqiang SHEN qiang State key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys

Effects of Ti and Be addition on microstructure and mechanical properties of Mg_(58.5)Cu_(30.5)Y_(11) bulk metallic glass

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Transactions of Nonferrous Metals Society of China 2015年第2期25卷 477-482页

作者：邱克强王琳任英磊李荣德沈阳工业大学材料科学与工程学院沈阳110870

Based on the Mg58.5Cu30.5Y11 alloy, 10% Ti, 10% Be and 10% Ti70Be30 （mole fraction） were respectively added to the alloy and samples with a diameter of 3 mm were fabricated by conventional Cu-mold casting method. The phase constituent, thermal stability and microstructure of the alloys were investigated by using X-ray diffraction, differential scanning calorimetry and scanning electron microscopy, respectively. The effects of alloying elements Ti and Be on the microstructure and mechanical properties of *** alloy were discussed. The results show that CuTi phase is distributed in （Mg0.585Cu0.305Y0.11）90Ti10 and （Mg58.5Cu30.5Y11）90（Ti0.7Be0.3）10 alloys, while CuYBe glassy phase containing CuY crystals is embedded in the matrix of （Mg58.5Cu30.5Y11）90Be10 alloy. Under uniaxial compressive loading, the largest compressive fracture strengths for （Mg58.5Cu30.5Y11）90Ti10, （Mg58.5Cu30.5Y11）90Be10 and （Mg58.5Cu30.5Y11）90（Ti0.7Be0.3）10 alloys are 797.6, 952.6 and 1007.8 MPa, respectively, and the strengths are increased by about 17%, 40% and 48% compared with Mg58.5Cu30.5Y11 alloy. The strength reliability for the three alloys is much improved according to the strength distribution region of 10 samples of each alloy.

关键词： Mg-based alloy alloying element Ti Be microstructure strength reliability