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| 1 | Thermal Growth and Nanomagnetism of the Quasi-one Dimensional Iron Oxide显示文摘Quasi-one dimensional iron oxide nanowires with flat needle shape were synthesized on the iron powders by a rather simple catalyst-free thermal oxidation process in ambient atmosphere. The characterization by field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman and high-resolution transmission electron microscopy (HRTEM) revealed that these nanostructures are single crystalline α-Fe2O3. The various dimensions with 40-170 nm in width and 1-8 μm in length were obtained by tuning the growth temperature from 280 to 480℃. A surface diffusion mechanism was proposed to account for the growth of quasi-one dimensional nanostructure. The typical α-Fe2O3 nanowires synthesized at 430℃ had a reduced Morin temperature TM of 131 K in comparison with their bulk counterpart. The coercivitis Hc of these nanowires are 321 and 65 Oe at 5 and 300 K, respectively. The temperature of synthesis also has important effects on the magnetic properties of these nanowires. | Minglong Zhong Zhongwu Liu Xichun Zhong Hongya Yu Dechang Zeng | 2011 | Journal of Materials Science & Technology2011，27，11： | 5 |
| 2 | Magnetic properties and magnetocaloric effects in amorphous and crystalline Gd_(55)Co_(35)Ni_(10) ribbons显示文摘The magnetic properties and magnetocaloric effects of amorphous and crystalline Gd55Co35Ni10 ribbons are investigated.A main phase with a Ho 12 Co 7-type monoclinic structure(space group P21/c) and a minor phase with a Ho4Co3-type hexagonal structure(space group P63/m) are obtained for crystalline ribbon after annealing.The amorphous ribbons order ferromagnetically and undergo a second-order transition at 192 K.For crystalline Gd55Co35Ni10 ribbons,two magnetic phase transitions occur at 158 and 214 K,respectively.The peak value of-△SM under a field change of 0-5 T is 6.5 J/kg K at 192 K for amorphous Gd55Co35Ni10 ribbons.A relatively large magnetic entropy change(~5.0 J/kg K) under a field change of 0-5 T for the crystalline Gd55Co35Ni10 ribbons is obtained in the temperature interval range of 154-214 K.The large platform of magnetic entropy change and the negligible thermal/magnetic hysteresis loss mean the crystalline Gd55Co35Ni10 compound can satisfy the requirement of the Ericsson-type refrigerator working in the temperature range from 154K to 214K. | ZHONG XiChun TANG PengFei GAO BeiBei MIN JiXiong LIU ZhongWu ZHENG ZhiGang ZENG DeChang YU HongYa QIU WanQi | 2013 | Science China(Physics,Mechanics & Astronomy)2013，56，6： | 3 |
| 3 | Structure and magneto-electrical properties of Fe-C films prepared by magnetron sputtering显示文摘Fe-doped amorphous Fe x C 1 x granular films were prepared on n-Si(100) substrates by d.c.magnetron sputtering.The structural properties of Fe x C 1 x films were investigated by X-ray diffraction(XRD),atomic force microscope(AFM) and Raman spectroscopy.The results show that the iron and carbon of as-deposited films are in amorphous state,and the Fe x C 1 x films are diamond-like carbon(DLC) films.After doping iron into the DLC films,a smooth surface morphology of the Fe x C 1 x films has been obtained with the surface roughness Ra of about 0.231 nm for x=18at%.The Fe x C 1 x films have good soft magnetic properties with the coercivity of approximately 20 Oe.A high positive magnetoresistance(MR) up to 93% with x=1at% was observed in a Fe x C 1 x granular film at 300 K.The resistance characteristic of Fe-C films is changed at about 230 K and the positive MR effect can be understood by the p-n heterojunction theory. | MA Lei LIU ZhongWu ZENG DeChang YU HongYa ZHONG XiaPing ZHANG XiaoZhong | 2012 | Science China(Physics,Mechanics & Astronomy)2012，55，9： | 3 |
| 4 | Microstructure of pre-sintered permanent magnetic strontium ferrite powder显示文摘The microstructure and characteristics of pre-sintered strontium ferrite powder were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The present study shows that the pre-sintered strontium ferrite powder is provided with a certain particle size distribution, which results in high-density magnets. The strontium ferrite particle has a laminar hexagonal structure with a size similar to ferrite single domain. Ferric oxide phase due to an incomplete solid phase reaction in the first sintering is discovered, which will deteriorate the magnetic properties of ferrite magnet. In addition, the waste ferrite magnets with needle shape arranging along C axis in good order into the powders are found, which have no negative effects on finished product quality. | YU Hongya LIU Zhengyi ZENG Dechang | 2006 | Rare Metals2006，25，z1： | 2 |
| 5 | Solution of the problem of determination of the density of heat flow due to high-pressure gas quenching by the finite-element method显示文摘 | Huang Peng Wie Xingzhao Zhang Weiwen Zeng Dechang | 2006 | Metal Science and Heat Treatment (-)2006，，5： | 1 |
| 6 | TEM observation of sintered permanent magnetic strontium ferrite显示文摘Sintered permanent magnetic strontium ferrites were studied using transmission electron microscopy to investigate the microstructure morphology and its correlation with the magnetic properties. The present study shows that the microstructure of sintered permanent magnetic strontium ferrites is an important parameter in determining their magnetic properties. The microstructure morphology in low-performance ferrite magnet is obviously different from high-performance one. The magnetic properties of sintered permanent strontium ferrite depend strongly on the orientation degree of strong magnetic crystals. The presence of ferric oxide phase in ferrite magnet can deteriorate the magnetic properties. Moreover, proper quantities of crystal defects are beneficial to high coercive force due to the fixing of magnetic domain. | YU Hongya LIU Zhengyi ZENG Dechang | 2006 | Rare Metals2006，25，z1： | 1 |
| 7 | Effect of Wuda granule on gastrointestinal function recovery after laparoscopic intestinal resection:a randomized–controlled trial显示文摘Background Previous studies have suggested that the Wuda granule(WDG)could promote the recovery of gastrointestinal(GI)function after gynecologic abdominal surgery.This trial aimed to investigate the efficacy and safety of WDG in the rapid recovery of GI function in patients after laparoscopic intestinal resection in the setting of enhanced recovery after surgery(ERAS)-based perioperative care.Methods We performed a randomized,double-blind,placebo-controlled pilot trial.Thirty patients who met the inclusion criteria were randomly assigned to either the WDG group or the placebo group in a 1:1 ratio.The patients received WDG or placebo twice a day in addition to ERAS-based perioperative care,starting on post-operative Day 1 until Day 3.The primary outcomes were time to first bowel movement and time to first tolerance of solid food.The secondary outcomes were time to first flatus,length of hospital stay(LOS),and post-operative ileus-related morbidity.Adverse events were also recorded.Results There were no statistically significant differences in baseline characteristics between the two groups.The median time to first bowel movement was significantly decreased in the WDG group compared with the control group(27.6 vs 50.1 h;P<0.001),but the median times to first flatus(22.9 vs 25.1 h;P>0.05)and LOS(5.0 vs 5.0 days;P>0.05)were not statistically different.The occurrence rates of post-operative nausea,vomiting,abdominal distension,and abdominal pain were similar in the two groups.No adverse events occurred in any patients.Conclusions The addition of WDG to ERAS post-operative care after laparoscopic intestinal resection can safely promote the rapid recovery of GI function. | Haiping Zeng Wei Wang Lixing Cao Yuyan Wu Wenwei Ouyang Dechang Diao Jin Wan Qicheng Chen Zhiqiang Chen | 2022 | Gastroenterology Report2022，10，1： | 1 |
| 8 | Magnetic properties and magnetoresistance of Co_xC_(1-x) granular films prepared by magnetron sputtering显示文摘Amorphous CoxC1-x granular films were prepared on n-Si(100) substrate by dc magnetron sputtering.The effects of Co concentration,film thickness and annealing temperature on the magnetic properties and magnetoresistance(MR) were investigated.After annealing at 500°C for 0.5 hour,the Co(002) peak of the CoxC1-x(x>2.5 at.%) films was observed,but cracks appeared in the films.Saturation magnetization Ms increased steadily with the increase of Co concentration from 2.5 at.% to 50 at.% and also increased with annealing temperature from room temperature to 400°C.The coercivity of CoxC1-x films was less than 180 Oe.The as-deposited Co2.5C97.5 granular films with 80 nm thickness showed a highly positive MR,up to 15.5% at a magnetic field of 0.8 T,observed at T=300 K when the external magnetic field was perpendicular to the film surface.With increasing film thickness and annealing temperature,the value of MR was found to decrease gradually and changed from positive to negative.The MR effect of the CoxC1-x granular films can be explained by p-n heterojunction theory and interface scattering effect. | MA Lei LIU ZhongWu ZENG DeChang ZHONG XiaPing ZHANG XiaoZhong | 2011 | Science China(Physics,Mechanics & Astronomy)2011，54，7： | 1 |
| 9 | Nucleation barrier height in undercooled metallic melts显示文摘The phase-field model of a liquid-to-solid transition was constructed where the model parameters were linked quantitatively to the interfacial properties,and the variation of nucleation barrier height in undercooled metallic melts with respect to undercooling was studied respectively based on two kinds of forms of local free energy density.The calculation results show that,with the increase of undercooling,the critical nucleus does not show bulk properties,and the nucleation barrier height decreases gradually and deviates more and more from that predicted by the classical nucleation theory in both cases.The physical spinodal occurs for a specific form of the local free energy density,where the nucleation barrier height vanishes when the undercooling reaches a critical value and the reduced nucleation barrier height can be expressed by a function of the ratio of undercooling to critical undercooling. | Gang WANG Dechang ZENG Zhongwu LIU | 2012 | Acta Metallurgica Sinica(English Letters)2012，25，4： | 0 |
| 10 | Study on structure and magnetic entropy changes of Ce_(2-x)Pr_xFe_(16.5)Co_(0.5) alloys显示文摘A series of Ce2-xPrxFe16.5Co0.5 alloys were prepared by arc melting under purified argon atmosphere. The structure and magnetic entropy changes in Ce2-xPrxFe16.5Co0.5 alloys were investigated by means of X-ray diffraction pattern and MPMS XL-7 magnetometer. The experimental results show that the crystal structure of Ce2-xPrxFe16.5Co0.5 alloys keeps in Th2Zn17-type rhombohedral, and the Curie temperature of Ce2-xPrxFe16.5Co0.5 alloys can be shifted to room temperature around by a composition adjustment. The magnetic entropy changes (-ΔSM) in Ce2-xPrxFe16.5Co0.5 alloys are relatively large, and a platform of magnetic entropy changes appears near the temperature TC. Ce2-xPrxFe16.5Co0.5 alloys are the potential working media for magnetic refrigeration with their stable chemical properties and especially low price. | ZHONG Xichun ZENG Dechang LUO Zhijian | 2006 | Rare Metals2006，25，z1： | 0 |
| 11 | Microstructure and sliding wear behavior of pseudo-alloy PS45/CuAl8 composite coating sprayed by HVAA technique显示文摘A pseudo-alloy PS45/CuAl8 composite coating was sprayed on steel substrate by high-velocity activated arc spraying (HVAA) process. Its sliding wear behavior at room temperature was evaluated by M-2000 wear tester. For comparison, a single CuAl8 coating was also prepared and tested under the same conditions. It is found that the pseudo-alloy composite coating consists of α-Cu and γ-Ni metallic matrix phases together with homogenously distributed minor Al 2 O 3 , Cr 2 O 3 oxide phases. Moreover, pseudo-alloy coating possesses much better sliding wear resistance than CuAl8 coating due to the enhanced hardness and microstructural homogenization. Fatigue wear and abrasive wear are responsible for the wear-down mechanism of the pseudo-alloy coating. | WU Yaosha a , ZENG Dechang a , LIU Zhongwu a , QIU Wanqi a , YU Hongya a , ZHONG Xichun a , LI Shangzhou a , and MA Yuexin b a School of Materials Science & Engineering, South China University of Technology, Guangzhou 510640, China b Optoelectronic Engineering Department, Zhongshan Torch Polytechnic, Zhongshan 528436, China | 2012 | Rare Metals2012，31，2： | 0 |
| 12 | Structure,magnetic properties and magnetocaloric effects of Fe_(50)Mn_(15-x)Co_xNi_(35) alloys显示文摘Fe50Mn15-xCoxNi35(x=0,1,3,5,7)alloys were prepared by arc melting under purified argon atmosphere.The ingots were homogenized at 930°C for 90h followed by water quenching.The crystal structure,magnetic properties and magnetocaloric effects of the alloys were studied by X-ray diffraction(XRD)and MPMS-7-type SQUID.The results show that all samples still maintained a single-(Fe,Ni)-type phase structure.With the increase of the content of Co,the Curie temperatures of these alloys increased and exhibited a second-order magnetic transition from ferromagnetic(FM)to paramagnetic(PM)state near Curie temperature.The maximum magnetic entropy change and the relative cooling power of Fe50Mn10Co5Ni35alloy was 2.55 J/kg·K and 181 J/kg,respectively,for an external field change of 5T.Compared with rare earth metal Gd,Fe50Mn15-xCoxNi35 series of alloys have obvious advantage in resource price;their Curie temperatures can be tuned to near room temperature,maintain a relatively large magnetic entropy change at the same time and they are a type of potential magnetic refrigeration materials near room temperature. | ZHONG XiChun TIAN HuaCun TANG PengFei LIU ZhongWu ZHENG ZhiGang ZENG DeChang | 2014 | Science China(Physics,Mechanics & Astronomy)2014，57，3： | 0 |
| 13 | INFLUENCE OF NANOMETER GRAIN SIZE OF Bi-2212 PHASE ON SUPERCONDUCTIVITY显示文摘INFLUENCEOFNANOMETERGRAINSIZEOFBi-2212PHASEONSUPERCONDUCTIVITY￥ZHANGCheng;WANGYongzhong;JIANGMing;ZENGDechang;TANGHong;LIZhon... | ZHANG Cheng WANG Yongzhong JIANG Ming ZENG Dechang TANG Hong LI Zhongrun QIAO Guiwen CHUANG Yuzhi(Institute of Metal Research,Chinese Academy of Sciences,Shenyang,China) | 1995 | Acta Metallurgica Sinica(English Letters)1995，8，2： | 0 |
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