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Chinese Chemical Letters 2006年第8期17卷 1061-1064页

作者： wen long ZHANG yan Mei WANG Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026

Quasi-interpenetrating network formed by polyacrylamide and poly （N-hydroxymethylacrylamide） was designed, synthesized, and tested for DNA sequencing by capillary electrophoresis. The performance of quasi-IPN on DNA... 详细信息

关键词： Capillary electrophoresis DNA sequencing quasi-interpenetrating network.

Preparation and properties of hot-deformed magnets processed from nanocrystalline/amorphous Nd-Fe-B powders

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Rare Metals 2021年第8期40卷 2033-2039页

作者： Peng Zhao yang Luo Dun-Bo Yu Hai-Jun Peng wen-long yan Zi-long Wang Xin-Yuan Bai National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsBeijing100088China Grirem Advanced Materials Co. LtdBeijing100088China

The hot-deformed magnets processed from nanocrystalline/amorphous Nd-Fe-B powders were preparedunderdifferenthot-pressingtemperatures(600-750℃,at intervals of 25℃)by the self-made hotpressing *** microstructure and magnetic properties of hot-deformed magnets prepared at different temperatures were also *** the temperature is above 650℃,the density of magnet reaches 7.5 g·cm^(-3).The optimum magnetic properties of magnetic induction intensity of B_(r)=1.3 T,optimum energy product of(BH)_(max)=282.5 kJ·m^(-3),intrinsiccoercivityof H_(cj)=1130.0 kA·m-1 of hot-deformed magnets are obtained at hot-pressing temperature of 650℃.X-ray diffractometer pattern shows that the(00 L)texture has been *** the microstructural characteristic,on the one hand,the good magnetic performance is attributed to the fine platelet-like grains with an average length of 410-440 nm at the hot-pressing temperature range from625 to 675℃.On the other hand,the unaligned coarse grains are observed in all the *** the areal fraction of those is gradually increasing with the rise of the hot-pressing temperature,which tends to deteriorate the magnetic *** composition map shows the accumulation of Nd/Pr-rich phase in the coarse grains’region.

关键词： Nanocrystalline/amorphous powders Hotpressing temperature Hot-deformed Magnets Magnetic properties Microstructure

Crystal structure and magnetic properties of SmFe_(9-x)Co_x alloys

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Rare Metals 2014年第1期33卷 54-57页

作者： yang Luo Dun-Bo Yu Hong-Wei Li Wei-Dong Zhuang Kuo-She Li wen-long yan National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co. Ltd

The crystal structure and magnetic properties of SmFeg_xCox （x = 0, 1, 3, 5） alloys were studied by X-ray powder diffraction （XRD） and magnetic measurements. The Th2Znl7-type structure of the as-cast state is changed to TbCu7-type structure after quenching to a rotating molybdenum roll under certain velocity （12, 20, and 32 m.s-l）. The （002） XRD peak appears and ^-Fe phase disappears when the Co is added up to x = 5. Saturation magnetization of SmFe9 under different temperature shows 9 % change （112-102 A.m2.g-1） when the temperature is higher than 200 K. The saturation magnetization is 115 A.m2.g-1 and coercivity is 0.304 T at 5 K for SmFe9 alloys. Increased saturation magnetization and decreased coercivity can be obtained for Co added up to x = 5 at 5 K.

关键词： TbCu7-type Crystal structure SmFe Magnetic properties

Structure and magnetic properties of melt-spun Sm-Fe-Nb ribbons and their nitrides

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Rare Metals 2018年第3期37卷 232-236页

作者： wen-long yan yang Luo Dun-Bo Yu Gui-Yong Wu Ning-Tao Quan Yuan-Fei yang Hai-Jun Peng Zi-long Wang National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsGrirem Advanced Materials Co. Ltd.

SmFe（10-x）Nbx（x = 0, 0.1, 0.2, 0.3） ribbons and their nitrides were prepared by melt-spinning, followed by annealing and subsequent nitriding. The structure and magnetic properties were investigated by means of X-ray diffraction（XRD） using the Rietveld method, vibrating sample magnetometer（VSM）, transmission electron microscope（TEM） and Mossbauer spectroscopy. XRD analysis shows that the addition of Nb can impede the precipitation of Sm2 Fe（17） and a-Fe phases and the Nb atoms occupy 2 e site in the alloys. At 300 K, the mean hyperfine fields of 2 e site are 29.58 T with Nb doping at x = 0.1 and the corresponding Curie temperature is 552 K. The optimal properties of remanence of Br = 0.9 T, intrinsic coercivity of H（cj）= 741.5 kA·m^-1, and maximum magnetic energy product of（BH）（max）= 124.2 kJ·m-（-3） are gained at x = 0.10 in the nitrides.

关键词： Melt-spinning SmFe10-xNbx powders Magnetic properties XRD Rietveld Mssbauer spectroscopy

Actin and Myosin Co-Localize in Plasmodesmata and Ectodesmata-Like Structure

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Agricultural Sciences in China 2011年第6期10卷 845-849页

作者： DONG Yu LIU Na LIU Gang LI wen-long yan Ai-hua WANG Dong-mei College of Life Science Agricultural University of Hebei Baoding 071001 P.R. China

Actin and myosin were found to be associated with the cytoplasmic sleeve of plasmodesmata. As cytoskeletal proteins, actin and myosin are believed to regulate the conductivity of plasmodesmata （PDs） in higher plants. Using immunocytochemical methods, we found the two proteins to be co-localized - and closely linked to each other - in plasmodesmata and ectodesmata-like structure in ageing parenchymatous cells of Allium sativum L. We suggest that intercellular communication is affected by the interaction between actin and myosin.

关键词： actin myosin plasmodesmata ectodesmata-like structure Allium sativum L.

Structure,nitridation efficiency and magnetic properties of SmFe powders and its nitrides

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Rare Metals 2023年第6期42卷 1983-1988页

作者： Xiao-Xia Chen yang Luo Zhou Hu wen-long yan Ning-Tao Quan Shuo Lu Dun-Bo Yu Jia-Jun Xie National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.Beijing100088China

The effect of annealing temperature(TA) at600-900℃ on structure and magnetic properties of the melt-spun Sm_(8.6)Fe_(85.9)Co_(4.3)Zr_(1.2) alloys and its nitrides was *** show that the melt-spun powder is TbCu7-type SmFe_(9) single phase.X-ray diffractometer(XRD) Rietveld refinement shows that the lattice parameter a increases,c and c/a decrease with the increase in T_(A) at600-700℃.This is due to the tendency of nitrogen entering into the 3f site(1/2,0,0) during the nitridation process,which is good for the magnetic *** phase transforms from TbCu7-type SmFe_(9) to Th_(2)Zn_(17)-type Sm_(2)Fe_(17) at above 800 *** electron microscopy(SEM) images show that the amount of surface defects of melt-spun powder which are harmful for magnetic properties decreases at first and then increases as TA *** coercivity(H_(cj)) and maximum magnetic energy product((BH)_(max)) of its nitrides increase first and then decrease as a function of *** the remanence(B_(r))always shows a *** optimal magnetic properties of H_(cj)=748 kA·m^(-1),B_(r)=0.92 T,(BH)_(max)=118 kJ·m^(-3) are obtained by annealing at 675℃ for 2 h and then nitriding at 460℃ for 10 h.

关键词： Melt-spun alloy Annealing temperature Magnetic property XRD Rietveld refinement

Structural properties and crystal orientation of polycrystalline Gd films

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Rare Metals 2023年第4期42卷 1414-1419页

作者： Yu-Zhou Zhang Shi-Rong Zhang Dun-Bo Yu yang Luo Ning-Tao Quan wen-long yan Kuo-She Li National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsBeijing100088China Grirem Advanced Materials Co.Ltd. Beijing100088China

To get a systematic understanding about dependence of deposition conditions on properties of Gd films,a series of Gd films were prepared under different Ar gas pressures:0.5,0.7,1.0,and 1.5 Pa,and another series of Gd films were prepared under different substrate temperatures:25,100,200,350,and 500℃.The effects of the deposition time,Ar pressure,and substrate temperature on microstructures and crystal orientation were investigated by grazingincidence X-ray diffraction(GIXRD)and transmission electron microscopy(TEM).The experimental results show that low Ar pressure and plenty deposition time will contribute to the formation of Gd hcp phase,which has better magnetic properties such as higher Curie temperature and bigger magnetic moment,and high substrate temperature can diminish the inner stress in Gd films and promote lattice parameters closer to those of the ideal Gd hcp-structure.

关键词： Thin film Size effects Grain orientation Heavy rare earth Nanocrystal Microstructure

The Effect of Blending Ratio on the Structure and Properties of the PPR/PS In situ Fiber Reinforced System Prepared by Multi-Flow Vibration Injection Molding

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Chinese Journal of Polymer Science 2024年第6期42卷 851-863页

作者： yan-Jiang Li Meng-long Hu Jun-wen Zhang Qiang Fu Jie Zhang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

To enhance the mechanical properties of polypropylene random copolymer(PPR),polystyrene(PS)with four different contents were added to the PPR matrix through melt ***,using the Multi-Flow Vibration Injection Molding(MFVIM)technology,PPR/PS in situ microfiber composites(MFC)with different blending ratios were *** results indicated that blending ratio had a great impact on the phase morphology and crystal structure of MFVIM samples,which was different from those of conventional injection molding(CIM)*** ultrafine fibers could be formed under the shear field and could absorb the PPR molecular chains to form hybrid shish-kebab ***,the PPR matrix could also form shish-kebab structures under the effect of strong *** the PS content reached 20%,under the combined action of PS in situ microfibers and highly oriented crystal structure,the tensile strength and Young’s modulus of the sample were obviously improved and the impact strength remained at a relatively high *** a strong and tough balanced PPR based material was *** results provide valuable insights for expanding the industrial and daily-life applications of PPR and show promising development prospects.

关键词： PPR MFVIM In situ microfibers Shearfield Hybrid shish-kebab structures

Structure and magnetic properties of TbCu_7-type melt-spun Sm–Fe–B alloys

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Rare Metals 2019年第2期38卷 151-156页

作者： Chuan-Jiang Zheng yang Luo Dun-Bo Yu wen-long yan Hong-Wei Li Yong-Jun Mao Shuo Lu Ning-Tao Quan National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co. Ltd.

The melt-spun SmFe_(12)B_x(x = 0, 0.50, 0.75,1.00, 1.25 and 1.50) ribbons were prepared at 40 m·s^(-1),and their structure and magnetic properties were studied by powder X-ray diffraction(XRD), vibrating sample magnetometer(VSM) and transmission electron microscopy(TEM). XRD results indicate that SmFe_(12)B_x alloys with 0.50 ≤ x ≤ 1.00 are composed of single-phase TbCu_7-type structure. Moreover, it is found that the boron addition can inhibit the emergence of soft magnetic phase a-Fe and result in the increase in the axial ratio c/a. After annealing at 650 ℃ for 0.5 h, the metastable phase TbCu_7 initially decomposes into the stable phase Sm_2Fe_(14)B(Nd_2Fe_(14)B-type) and a-Fe. The value of magnetic moment per Fe atom increases slightly from 1.75 uB for boron-free sample to 1.80 uB for the x = 0.75 sample and then decreases *** addition, the best magnetic properties of maximum energy product [(BH)_(max)] of 14.56 kJ·m^(-3), coercivity(H_(cj))of 172.6 kA·m^(-1) and remanence(B_r) of 0.45 T are obtained for the SmFe_(12)B_(1.00) alloy. Based on transmission electron microscopy(TEM) results, the average size of grains is around 197 nm for B-free sample and decreases to 95 nm for x = 1.00 sample, indicating that the addition of boron can refine grains.

关键词： TbCu7-type structure Sm-Fe-B ribbons Phase formation Magnetic moment Microstructure

Structural transformation and magnetic properties of Sm-Fe alloys with V doping

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Rare Metals 2022年第7期41卷 2349-2352页

作者： Yong-Jun Mao Jin-Ling Jin Jia-Jun Xie yang Luo Kuo-She Li wen-long yan Dun-Bo Yu Hong-Wei Li National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsBeijing 100088China Grirem Advanced Materials Co.Ltd. Beijing 100088China

A systematical investigation was carried out on structure and magnetic properties in SmFe_(9-x)V_(x)(x=0.4,0.8,1.2)compounds prepared by a single-roller quenching *** high cool-down rate leads to metastable TbCu_(7) phase in the parent compound,which gradually transforms into equilibrium ThMn_(12) structure with V-doping content *** Curie temperature increases from 470 to 590 K with V doping,which is consistent with the phase ***,simultaneous increase in both coercivity and remanence is resulted by V doping,reaching the highest value of 685 kA·m^(-1)and 44.8×10^(-3)A·m^(2)·g^(-1)in x=1.2 compound,*** phenomenon can be explained by the combination of phase transformation and intergranular exchange coupling throughδM-H plots.

关键词： Phase transformation Magnetic properties Exchange coupling Element doping ThMn12-type phase