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Pharmacological intervention for chronic phase of spinal cord injury
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作者 Chihiro Tohda 《Neural Regeneration Research》 SCIE CAS 2025年第5期1377-1389,共13页
Spinal cord injury is an intractable traumatic injury. The most common hurdles faced during spinal cord injury are failure of axonal regrowth and reconnection to target sites. These also tend to be the most challengin... Spinal cord injury is an intractable traumatic injury. The most common hurdles faced during spinal cord injury are failure of axonal regrowth and reconnection to target sites. These also tend to be the most challenging issues in spinal cord injury. As spinal cord injury progresses to the chronic phase, lost motor and sensory functions are not recovered. Several reasons may be attributed to the failure of recovery from chronic spinal cord injury. These include factors that inhibit axonal growth such as activated astrocytes, chondroitin sulfate proteoglycan, myelin-associated proteins, inflammatory microglia, and fibroblasts that accumulate at lesion sites. Skeletal muscle atrophy due to denervation is another chronic and detrimental spinal cord injury–specific condition. Although several intervention strategies based on multiple outlooks have been attempted for treating spinal cord injury, few approaches have been successful. To treat chronic spinal cord injury, neural cells or tissue substitutes may need to be supplied in the cavity area to enable possible axonal growth. Additionally, stimulating axonal growth activity by extrinsic factors is extremely important and essential for maintaining the remaining host neurons and transplanted neurons. This review focuses on pharmacotherapeutic approaches using small compounds and proteins to enable axonal growth in chronic spinal cord injury. This review presents some of these candidates that have shown promising outcomes in basic research(in vivo animal studies) and clinical trials: AA-NgR(310)ecto-Fc(AXER-204), fasudil, phosphatase and tensin homolog protein antagonist peptide 4, chondroitinase ABC, intracellular sigma peptide,(-)-epigallocatechin gallate, matrine, acteoside, pyrvate kinase M2, diosgenin, granulocyte-colony stimulating factor, and fampridine-sustained release. Although the current situation suggests that drug-based therapies to recover function in chronic spinal cord injury are limited, potential candidates have been identified through basic research, and these candidates may be subjects of clinical studies in the future. Moreover, cocktail therapy comprising drugs with varied underlying mechanisms may be effective in treating the refractory status of chronic spinal cord injury. 展开更多
关键词 axonal growth chronic phase clinical study PHARMACOTHERAPY spinal cord injury
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Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption
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作者 Zizhuang He Lingzi Shi +6 位作者 Ran Sun Lianfei Ding Mukun He Jiaming Li Hua Guo Tiande Gao Panbo Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期191-204,共14页
Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significan... Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase evolution.Herein,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation process.The results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial polarization.Moreover,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic diffraction.Specifically,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon matrix.This design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption. 展开更多
关键词 Magnetic heterointerfaces phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption
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As-cast microstructure and Sr-containing phases of AZ31 magnesium alloys with high Sr contents 被引量:5
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作者 吴璐 潘复生 +2 位作者 杨明波 吴菊英 刘婷婷 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期784-789,共6页
The as-cast microstructure and Sr-containing phases in the AZ31 magnesium alloys with different Sr contents (0%, 0.3%, 2.5% and 5.0%, mass fraction) were investigated. The results indicate that after adding Sr to th... The as-cast microstructure and Sr-containing phases in the AZ31 magnesium alloys with different Sr contents (0%, 0.3%, 2.5% and 5.0%, mass fraction) were investigated. The results indicate that after adding Sr to the AZ31 magnesium alloy, the dendrite/grain size is decreased, and with the Sr content increasing from 0 to 5.0%, the dendrite becomes finer, the dendrite morphology becomes more passive and the distribution of alloying phases at dendrite/grain boundary is dispersed. Furthermore, the morphology of the β-Mg 17 Al 12 phase in the alloy with addition of 0.3%Sr changes from continuously irregular strip-like shape to discontinuously irregular strip-like shape and/or fine granule-like shape. At the same time, some lamella-like eutectic phases are found in the alloys with additions of 2.5% Sr and 5.0% Sr, and the lamella spacing in the alloy with addition of 5.0% Sr is finer. Adding high Sr content to the AZ31 alloy can bring the new ternary eutectic and/or divorced eutectic phase of Mg 11 Al 5 Zn 4 in the alloy, and the Mg 17 Sr 2 and Mg 2 Sr phases are formed in the alloys with additions of 2.5% Sr and 5.0% Sr. 展开更多
关键词 magnesium alloy AZ31 magnesium alloy Sr-containing phase SR
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EFFECT OF Mn CONTENT ON KINETIC PARAMETER DURING PHASE TRANSFORMATION IN CuZnAlMnNi SHAPE MEMORY ALLOYS 被引量:2
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作者 Geng, GL Bai, YJ 《中国有色金属学会会刊:英文版》 CSCD 1996年第3期150-152,共3页
EFFECTOFMnCONTENTONKINETICPARAMETERDURINGPHASETRANSFORMATIONINCuZnAlMnNiSHAPEMEMORYALLOYS¥GengGuili(Institut... EFFECTOFMnCONTENTONKINETICPARAMETERDURINGPHASETRANSFORMATIONINCuZnAlMnNiSHAPEMEMORYALLOYS¥GengGuili(InstituteforMaterialsEngi... 展开更多
关键词 Mn content CuZnAlMnNi SHAPE MEMORY alloy phase TRANSFORMATION KINETIC PARAMETER
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基于CTA颅内动脉瘤形态联合PHASES评分对破裂出血预测研究
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作者 王金泉 黄吉淮 谢颖 《影像研究与医学应用》 2024年第4期31-34,共4页
目的:分析头颈部计算机断层扫描血管成像(CTA)联合PHASES评分对颅内动脉瘤(IA)破裂出血的预测价值。方法:回顾性分析2021年10月—2023年9月东莞市长安医院诊治的IA患者临床资料,根据IA破裂出血与否分为IA破裂组(n=46)和IA未破裂组(n=44)... 目的:分析头颈部计算机断层扫描血管成像(CTA)联合PHASES评分对颅内动脉瘤(IA)破裂出血的预测价值。方法:回顾性分析2021年10月—2023年9月东莞市长安医院诊治的IA患者临床资料,根据IA破裂出血与否分为IA破裂组(n=46)和IA未破裂组(n=44),收集两组临床资料,对比两组患者CTA影像瘤体特征参数和PHASES评分结果。采用受试者工作特征(ROC)曲线分析两者联合预测动脉瘤破裂的效能。结果:IA破裂组高血压、糖尿病发生率及PHASES评分均高于IA未破裂组,差异有统计学意义(P <0.05)。两组病灶位置以颈内动脉(ICA)和大脑中动脉(MCA)为主,但IA破裂组病灶位置在MCA的占比为41.30%,高于IA未破裂组的20.45%,瘤体>7 mm的最多(瘤体7~9.9 mm占65.22%),瘤体形态不规则占58.7%,未破裂组病灶位置在ICA最多(68.18%),瘤体<7 mm的居多(75.00%),瘤体形态规则囊状动脉瘤占93.18%,差异有统计学意义(P <0.05)。CTA瘤体特征参数比较,IA破裂组患者瘤颈宽度、瘤体高度、瘤体长度、动脉瘤最大直径、入射夹角、动脉瘤体颈比等参数均高于IA未破裂组,差异有统计学意义(P <0.05)。CTA瘤体特征参数+PHASES评分联合预测曲线下面积为0.916,高于CTA瘤体特征参数(0.901)和PHASES评分(0.731)。结论:CTA瘤体特征参数+PHASES评分联合预测IA患者破裂出血效能最佳。 展开更多
关键词 颅内动脉瘤 破裂出血 CTA phaseS评分
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Effect of Cr content and cooling rate on the primary phase of Al-2.5Mn alloy 被引量:1
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作者 Hang-qi Feng Zhi-bo Yang +2 位作者 Ye-tong Bai Li Zhang Yu-lin Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第12期1551-1558,共8页
The effect of Cr content and cooling rate on the microstructure of Al-Mn alloy was studied using well resistance furnace melting,and the alloy was analyzed using scanning electron microscopy(SEM)and X-ray diffraction(... The effect of Cr content and cooling rate on the microstructure of Al-Mn alloy was studied using well resistance furnace melting,and the alloy was analyzed using scanning electron microscopy(SEM)and X-ray diffraction(XRD).The experimental results showed that adding Cr could significantly improve the morphology of the primary phase in the Al-2.5Mn alloy.Without Cr,the primary phase in the alloy was thick,needle-like,and strip-like structure.After adding 0.2wt%-0.5wt%Cr,the primary phase in the upper part of the alloy was gradually fined and reached the best effect at 0.35wt%Cr.When the content of Cr was 0.5wt%,the microstructure of the primary phase in the upper part began to coarsen.The bottom of the alloy was a large bulk phase,but still much finer than that without adding Cr.XRD and SEM analysis showed that the precipitation phase at the bottom was mainly Al85Mn7Cr8,while the fine microstructure at the top was Al6Mn and Al3Mn.The results of the cooling rate experiments showed that the primary phase of Al-2.5Mn-0.35Cr was further refined,and the eutectic microstructure was partly achieved,under air-cooling condition.And when the cooling method was iron die-cooling,the microstructure of the Al-2.5Mn-0.35Cr alloy was changed into a eutectic microstructure. 展开更多
关键词 Al-2.5Mn ALLOY Cr content PRIMARY phase COOLING rate
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CRYSTALLISATION KINETICS AND PHASE TRANSFORMATION BEHAVIOUR OF ELECTROLESS NICKEL-PHOSPHORUS DEPOSIT WITH 6-9wt% PHOSPHORUS CONTENT 被引量:4
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作者 K.G. Keong, W. Sha and S. Malinov (School of Civil Engineering, The Queen’s University of Belfast, Belfast BT7 1NN, UK) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2001年第6期419-424,共6页
Crystallisation kinetic and phase transformation behaviour of the electroless nickel-phosphorus deposit with 6-9wt% phosphorus content were studied. The deposit was heated in the differential scanning calorimetry (DSC... Crystallisation kinetic and phase transformation behaviour of the electroless nickel-phosphorus deposit with 6-9wt% phosphorus content were studied. The deposit was heated in the differential scanning calorimetry (DSC) apparatus to 300℃-800℃ at 20℃/min, followed by the X-ray diffraction (XRD) analysis. The sequence of crystallisation process was: mixture of amorphous and microcrystalline nickel phases → intermediate metastable, f. c. c. nickel and stable N13P phases → f. c. c. nickel and stable Ni3P phases. Preferred orientation of nickel {200} plane was developed after the heating processes. Activation energy of crystallisation process was determined from the DSC analyses at 5-50℃/min. Crystallisation temperatures were found increased with increasing heating rate. 展开更多
关键词 coating CRYSTALLIZATION NICKEL phase transitions PHOSPHORUS X-ray diffraction
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Effects of glutamine supplementation on gut barrier,glutathione content and acute phase response in malnourished rats during inflammatory shock 被引量:6
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作者 Liliana Belmonte Mose Co■ffier +8 位作者 Florence Le Pessot Olga Miralles-Barrachina Martine Hiron Antony Leplingard Jean-Franois Lemeland Bernadette Hecketsweiler Maryvonne Daveau Philippe Ducrotté Pierre Déchelotte 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第20期2833-2840,共8页
AIM: To evaluate the effect of glutamine on intestinal mucosa integrity,glutathione stores and acute phase response in protein-depleted rats during an inflammatory shock. METHODS: Plasma acute phase proteins (APP),jej... AIM: To evaluate the effect of glutamine on intestinal mucosa integrity,glutathione stores and acute phase response in protein-depleted rats during an inflammatory shock. METHODS: Plasma acute phase proteins (APP),jejunal APP mRNA levels,liver and jejunal glutathione concentrations were measured before and one,three and seven days after turpentine injection in 4 groups of control,protein-restricted,protein-restricted rats supplemented with glutamine or protein powder. Bacterial translocation in mesenteric lymph nodes and intestinal morphology were also assessed. RESULTS: Protein deprivation and turpentine injection significantly reduced jejunal villus height,and crypt depths. Mucosal glutathione concentration significantly decreased in protein-restricted rats. Before turpentine oil,glutamine supplementation restored villus heights and glutathione concentration (3.24 ± 1.05 vs 1.72 ± 0.46 μmol/g tissue,P < 0.05) in the jejunum,whereas in the liver glutathione remained low. Glutamine markedly increased jejunal α1-acid glycoprotein mRNA level after turpentine oil but did not affect its plasma concentration. Bacterial translocation in protein-restricted rats was not prevented by glutamine or protein powder supplementation. CONCLUSION: Glutamine restored gut glutathione stores and villus heights in malnourished rats but had no preventive effect on bacterial translocation in our model. 展开更多
关键词 Acute phase response GLUTAMINE GLUTATHIONE INTESTINE MALNUTRITION
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Anomalous pattern of ocean heat content during different phases of the solar cycle in the tropical Pacific 被引量:6
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作者 HUO Wen-Juan XIAO Zi-Niu 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第1期9-16,共8页
Solar radiation is a forcing of the climate system with a quasi-11-year period.As a quasi-period forcing,the influence of the phase of the solar cycle on the ocean system is an interesting topic of study.In this paper... Solar radiation is a forcing of the climate system with a quasi-11-year period.As a quasi-period forcing,the influence of the phase of the solar cycle on the ocean system is an interesting topic of study.In this paper,the authors investigate a particular feature,the ocean heat content(OHC)anomaly,in different phases of the total solar irradiance(TSI) cycle.The results show that almost opposite spatial patterns appear in the tropical Pacific during the ascending and declining phases of the TSI cycle.Further analysis reveals the presence of the quasi-decadal(11-year) solar signal in the SST,OHC and surface zonal wind anomaly field over the tropical Pacific with a high level of statistical confidence(95%).It is noted that the maximum centers of the ocean temperature anomaly are trapped in the upper ocean above the main pycnocline,in which the variations of OHC are related closely with zonal wind and ocean currents. 展开更多
关键词 Ocean heat content anomaly total solar irradiance solar cycle tropical Pacific
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Effect of Al content on the phase structure and the hydrogenation characteristic of La(Mg_(1-x)Al_x) alloys 被引量:1
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作者 HOU Qingyu ZHANG Qing'an 《Rare Metals》 SCIE EI CAS CSCD 2006年第6期654-658,共5页
La(Mg1-xAlx) (x=0.2, 0.4, 0.6, 0.8) alloys have been prepared using induction melting followed by annealing. It is found that partial substitution of Mg by Al does not lead to a change in crystal structure, and th... La(Mg1-xAlx) (x=0.2, 0.4, 0.6, 0.8) alloys have been prepared using induction melting followed by annealing. It is found that partial substitution of Mg by Al does not lead to a change in crystal structure, and the alloys have a single LaMg phase when x 〈 0.4. The lattice parameter of the LaMg phase decreases obviously after the partial substitution of Mg by Al. However, further substitution of Mg by Al leads to the coexistence of multiple phases when x ≥ 0.6. The alloys consist of the LaMg, LaAl, LaAl2, and La5Al4 phases. The LaMg phase decreases, whereas the La5Al4 phase increases with the increase in x. The Al-substituted La(Mgo.6Al0.4) alloy can be hydrogenated into the tetragonal LaH3, cubic LaH3, MgH2, and LaPd under 5 MPa at 473 K for 5 d. 展开更多
关键词 intermetallic compound phase structure hydrogenation characteristic X-ray diffraction
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Effect of Rhizobium Inoculation and Supplementation with Phosphorus and Potassium on Growth and Total Leaf Chlorophyll (Chl) Content of Bush Bean <i>Phaseolus vulgaris</i>, L. 被引量:2
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作者 Abdulkadir Mfilinge Kelvin Mtei Patrick Ndakidemi 《Agricultural Sciences》 2014年第14期1413-1426,共14页
The study was conducted to investigate the effect of Rhizobium inoculation and supplementation of phosphorus and potassium on growth and total leaf chlorophyll content to the three released bush bean varieties in nort... The study was conducted to investigate the effect of Rhizobium inoculation and supplementation of phosphorus and potassium on growth and total leaf chlorophyll content to the three released bush bean varieties in northern Tanzania. To achieve this aim, the glasshouse experiment was conducted at Nelson Mandela African Institution of Science and Technology while field experiment were carried out at Tanzania Coffee Research Institute, in Kilimanjaro, Tanzania between April-July 2014. The experiment was laid out in factorial arrangement. Factor I comprised of three bush bean varieties. Factor II involved two inoculation treatments viz 1) inoculation with Rhizobium spp. and 2) without inoculation. Factor III included four fertilizer levels (0 Kg·ha-1 20 Kg K ha-1, 30 Kg P ha-1 and 20 kg·K + 30 Kg P ha-1). Both screen house and field experiments were replicated four times. Plant growth parameters (plant height (cm), number leaves per plant, stem girth (mm)) were measured at 2, 4 and 6 weaks after planting (WAP). The chlorophyll was extracted by using Dimethylsulphoxide (DMSO) and absorbance was determined at 645 and 663nm using UV/Visible spectrophotometer. Results showed that Rhizobium application significantly improved the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content. Furthermore, compared with the zero treatment control, potassium fertilization significantly increased the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content of the three varieties. In general, these parameters were significantly increased with phosphorus supplied at 30 kg/ha. The combination of these supplies at different levels resulted in significant interactions in some parameters and thus indicating need for these inputs in the study area. 展开更多
关键词 Legumes Total LEAF CHLOROPHYLL content Photosynthesis Plant Height RHIZOBIA Stem Girth
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Efects of thermal aging temperature and Cr content on phase separ-ation kinetics in Fe-Cr alloys simulated by the phase feld method 被引量:1
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作者 Shu-xiao Li Hai-long Zhang +3 位作者 Shi-lei Li Yan-li Wang Fei Xue Xi-tao Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第11期1067-1075,共9页
Phase field simulations of phase separation in Fe-Cr binary alloys were performed by using the Cahn-Hilliard diffusion function. A new mobility model in relation to aging temperature and Cr content was used in the sim... Phase field simulations of phase separation in Fe-Cr binary alloys were performed by using the Cahn-Hilliard diffusion function. A new mobility model in relation to aging temperature and Cr content was used in the simulations. Two alloys of Fe-30at%Cr and Fe-35at%Cr were investigated at two different aging temperatures of 573 and 673 K. The phase separation kinetics was found to consist of three stages: wavelength modulation, amplitude increase, and coarsening of Cr-enriched regions. A higher thermal aging temperature accelerated the phase separation and increased the wavelength of concentration fluctuation. While the effect of Cr content on the phase separation kinetics was slight, Fe-Cr alloys with a higher Cr content were found to generate a larger number and a finer size of Cr-enriched regions. The simulation results provide consultation for design and safe operation of duplex stainless steel pipes in nuclear power plants. 展开更多
关键词 stainless steel duplex steel phase separation KINETICS nuclear power plants
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Observations and Modeling of Ice Water Content in a Mixed-Phase Cloud System 被引量:2
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作者 HOU Tuan-Jie LEI Heng-Chi +1 位作者 HU Zhao-Xia FENG Qiu-Juan 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第4期210-215,共6页
The ice water content(IWC) distribution in a mixed-phase cloud system was investigated using Cloud-Sat data,aircraft measurements,and the Weather Research and Forecasting(WRF) model.Simulated precipitation and IWC wer... The ice water content(IWC) distribution in a mixed-phase cloud system was investigated using Cloud-Sat data,aircraft measurements,and the Weather Research and Forecasting(WRF) model.Simulated precipitation and IWC were in general agreement with rain gauge,sat-ellite,and aircraft observations.The cloud case was char-acterized by a predominant cold layer and high IWC throughout the cloud-development and precipitation stages.The CloudSat-retrieved products suggested that the IWC was distributed from 4.0 to 8.0 km,with the maximum values(up to 0.5 g m-3) at 5.0-6.0 km at the earlymature stage of cloud development.High IWC(up to 0.8 g m-3) was also detected by airborne probes at 4.2 and 3.6 km at the late-mature stage.The WRF model simulation re-vealed that the predominant riming facilitated rapid ac-cumulation of high IWC at 3.0-6.0 km. 展开更多
关键词 aircraft observation ice water content WRF
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Hot deformation of Mg-Y-Zn alloy with a low content of the LPSO phase studied by in-situ synchrotron radiation diffraction 被引量:5
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作者 Klaudia Horváth Fekete Daria Drozdenko +5 位作者 Jan Capek Kristián Máthis Domonkos Tolnai Andreas Stark Gerardo Garcés Patrik Dobron 《Journal of Magnesium and Alloys》 SCIE 2020年第1期199-209,共11页
The compressive deformation behavior of the extruded WZ42(Mg98.5Y1Zn0.5 in at.%)magnesium alloy containing a low amount of long-period stacking ordered(LPSO)phase was studied by in-situ synchrotron radiation diffracti... The compressive deformation behavior of the extruded WZ42(Mg98.5Y1Zn0.5 in at.%)magnesium alloy containing a low amount of long-period stacking ordered(LPSO)phase was studied by in-situ synchrotron radiation diffraction technique.Tests were conducted at temperatures between room temperature and 350℃.Detailed microstructure investigation was provided by scanning electron microscopy,particularly the backscattered electron imaging and electron backscatter diffraction technique.The results show that twinning lost its dominance and kinking of the LPSO phase became more pronounced with increasing deformation temperature.No cracks of the LPSO phase and no debonding r at the interface between the LPSO phase and the Mg matrix were observed at temperatures above 200℃.At 350℃,the LPSO phase lost its strengthening effect and the deformation of the alloy was mainly realized by the dynamic recrystallization of the Mg matrix. 展开更多
关键词 Magnesium alloy LPSO phase KINKING High temperature Synchrotron radiation diffraction
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Effects of Ru content on phase transformation and compression property of cast TiAl alloys 被引量:3
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作者 Jie-ren Yang Zi-xiang Jiao +3 位作者 Dong-dong Zhu Yu-lun Wu Zi-tong Gao Rui Hu 《China Foundry》 SCIE CAS 2020年第6期393-401,共9页
Ruthenium(Ru)is a promising element to heighten the comprehensive mechanical properties of TiAl alloys.In the present study,the phase transformation during the cooling of Ti-47Al-2Cr-2Nb-xRu(x=0,0.1,0.5,1.0,at.%)alloy... Ruthenium(Ru)is a promising element to heighten the comprehensive mechanical properties of TiAl alloys.In the present study,the phase transformation during the cooling of Ti-47Al-2Cr-2Nb-xRu(x=0,0.1,0.5,1.0,at.%)alloys was investigated.The results show that Ru tends to segregate in the interdendritic region during solidification,and therefore,refines the as-cast microstructure of the alloys.As aβ-stabilizer,Ru does not induce a novel solidification reaction but maintains the peritectic reaction of L+β→α.An excessive Ru content would cause the formation of(γ+τ1+B2)and(α+γ+τ1+B2)phase regions below 1,250°C.The precipitation ofτ1-containing mixture is attributed to the Ru-segregation,which inhibits the reaction ofα→γand facilitates the formation of B2 phase.The discontinuous coarsening ofγphase and blockτ1 phase formed alternately in a manner of analogous eutectoid decomposition within B2 phase.In addition,the effect of Ru content on compression property of the alloys was studied.The yield strength increases up to 427 MPa at 800°C with the addition of 1.0at.%Ru,which is mainly due to the solution strengthening effect of Ru. 展开更多
关键词 TiAl alloy solidification path MICROSTRUCTURE phase transformation yield strength
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High performance RE–Fe–B sintered magnets with high-content misch metal by double main phase process 被引量:2
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作者 Yan-Li Liu Qiang Ma +5 位作者 Xin Wang Jian-Jun Zhou Tong-Yun Zhao Feng-Xia Hu Ji-Rong Sun Bao-Gen Shen 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期494-500,共7页
Double main phase process is applied to fabricate [(Pr, Nd)1 – xMMx]13.8FebalM1.5B5.9 (x = 0.5 and 0.7;M = Cu, Al, Co, and Nb) sintered magnets with high misch metal (MM) content. In comparison to the magnets by sing... Double main phase process is applied to fabricate [(Pr, Nd)1 – xMMx]13.8FebalM1.5B5.9 (x = 0.5 and 0.7;M = Cu, Al, Co, and Nb) sintered magnets with high misch metal (MM) content. In comparison to the magnets by single main phase process, the enhanced magnetic properties have been achieved. For magnets of x = 0.7, Hcj increases to 371.9 kA/m by 60.5%, and (BH)max is significantly enhanced to 253.3 kJ/m3 by 56.9%, compared with those of the single main phase magnets of the same nominal composition. In combination with minor loops and magnetic recoil curves, the property improvement of magnets with double main phase method is well explained. As a result, it is demonstrated that double main phase technology is an effective approach to improve the permanent magnetic properties of MM based sintered magnets. 展开更多
关键词 misch maetal double main phase process magnetic properties COERCIVITY
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Effects of magnesium content on phase constituents of Al-Mg-Si-Cu alloys 被引量:11
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作者 刘宏 赵刚 +1 位作者 刘春明 左良 《中国有色金属学会会刊:英文版》 EI CSCD 2006年第2期376-381,共6页
By means of scanning electron microscopy(SEM), energy dispersive spectrum(EDS), X-ray diffractometry(XRD) and metallographic analysis, the effects of variation of magnesium content on phase constituents of Al-Mg-Si-Cu... By means of scanning electron microscopy(SEM), energy dispersive spectrum(EDS), X-ray diffractometry(XRD) and metallographic analysis, the effects of variation of magnesium content on phase constituents of Al-Mg-Si-Cu alloys were investigated. The results indicate that the constituents formed during casting alloys are main Al1.9CuMg4.1Si3.3,Al4(MnFe)3Si2 and Mg2Si, while pure Si is only present in the alloy containing lower magnesium content. Increasing Mg content leads to increasing the amount of Mg2Si, but decreasing the amount of Al1.9CuMg4.1Si3.3 and Al4(MnFe)3Si2. During the following homogenization process, Al1.9CuMg4.1Si3.3 is completely dissolved, Al4(MnFe)3Si2 and pure Si remain unchanged. After rolling and final heat treatment, the constituents in the alloys change no longer. 展开更多
关键词 Al1.9CuMg4.1Si3.3 Al4(MnFe)3Si2 MG2SI 铝合金
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Effect of Y_2BaCuO_5 Phase Content on Magnetic Property in Bulk Melt-textured YBCO
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作者 付雪奎 肖玲 任洪涛 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第2期137-139,共3页
Bulk YBCO samples were prepared by PMP method. The nominal composition was Y123+xwt% Y211+10 wt% Ag2O (x= 0,15,25,40).The result of magnetic measurements indicated the sample with x= 1 5 at 77 K exhibited a J0 of 3. 9... Bulk YBCO samples were prepared by PMP method. The nominal composition was Y123+xwt% Y211+10 wt% Ag2O (x= 0,15,25,40).The result of magnetic measurements indicated the sample with x= 1 5 at 77 K exhibited a J0 of 3. 9 ×104 A/cm2 at 0.1 T and 2. 4 ×104A/cm2 at 1.0 T.The morphology of samples suggested that fine dispersed Y2BaCuO5 phase acts as effective pinning centers. 展开更多
关键词 Oxide superconductor Y_2BaCuO_5 phase content Magnetic property YTTRIUM
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Water Content Effect on Oxides Yield in Gas and Liquid Phase Using DBD Arrays in Mist Spray 被引量:1
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作者 陈秉岩 朱昌平 +7 位作者 费峻涛 何湘 殷澄 王媛 蒋永锋 陈龙威 高远 韩庆邦 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第1期41-50,共10页
Electric discharge in and in contact with water can accompany ultraviolet(UV)radiation and electron impact, which can generate a large number of active species such as hydroxyl radicals(OH), oxygen radical(O), o... Electric discharge in and in contact with water can accompany ultraviolet(UV)radiation and electron impact, which can generate a large number of active species such as hydroxyl radicals(OH), oxygen radical(O), ozone(O_3) and hydrogen peroxide(H_2O_2). In this paper, a nonthermal plasma processing system was established by means of dielectric barrier discharge(DBD)arrays in water mist spray. The relationship between droplet size and water content was examined,and the effects of the concentrations of oxides in both treated water and gas were investigated under different water content and discharge time. The relative intensity of UV spectra from DBD in water mist was a function of water content. The concentrations of both O_3 and nitrogen dioxide(NO_2) in DBD room decreased with increasing water content. Moreover, the concentrations of H_2O_2, O_3 and nitrogen oxides(NOx) in treated water decreased with increasing water content,and all the ones enhanced after discharge. The experimental results were further analyzed by chemical reaction equations and commented by physical principles as much as possible. At last,the water containing phenol was tested in this system for the concentration from 100 mg/L to9.8 mg/L in a period of 35 min. 展开更多
关键词 dielectric barrier discharge(DBD) water mist spray water content hydrogen peroxide ozone nitrogen oxides
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Electric properties and phase transition behavior in lead lanthanum zirconate stannate titanate ceramics with low zirconate content
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作者 曾涛 漏琦伟 +3 位作者 陈学锋 张红玲 董显林 王根水 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期497-501,共5页
The phase transitions, dielectric properties, and polarization versus electric field (P-E) hysteresis loops of Pbo.97Lao.02(Zr0.42Sn0.58-xTix)O3 (0.13≤ x ≤0.18) (PLZST) bulk ceramics were systematically inve... The phase transitions, dielectric properties, and polarization versus electric field (P-E) hysteresis loops of Pbo.97Lao.02(Zr0.42Sn0.58-xTix)O3 (0.13≤ x ≤0.18) (PLZST) bulk ceramics were systematically investigated. This study exhibited a sequence of phase transitions by analyzing the change of the P-E hysteresis loops with increasing temperature. The anfiferroelectric (AFE) to ferroelectric (FE) phase boundary of PLZST with the Zr content of 0.42 was found to locate at the Ti content between 0.14 and 0.15. This work is aimed to improve the ternary phase diagram of lanthanum-doped PZST with the Zr content of 0.42 and will be a good reference for seeking high energy storage density in the PLZST system with low-Zr content. 展开更多
关键词 PLZST ceramics FERROELECTRICITY ANTIFERROELECTRICITY phase transition
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