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镁及镁合金行业标准体系不断完善相关标准研制井喷可期 预览
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作者 席欢 《世界有色金属》 2019年第2期161-165,共5页
镁及镁合金广泛应用于汽车、3C产品、轨道交通、城市建设、医疗和军工等行业。SAC/TC243经过2018年12月对镁及镁合金行业2个月的研究工作,准备在镁及镁合金领域制定更多的系列标准,使镁及镁合金领域的标准体系能够完善和适应行业需要。
关键词 镁合金 标准 国际标准
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固态和液态镁及镁锂合金的密度 预览
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作者 R.N.ABDULLAEV R.A.KHAIRULIN +2 位作者 Yu.M.KOZLOVSKII A.Sh.AGAZHANOV S.V.STANKUS 《中国有色金属学报:英文版》 SCIE EI CAS CSCD 2019年第3期507-514,共8页
给出关于固体和液态的镁以及含23.03at.%和30.02at.%Li的超轻镁锂合金的密度和热膨胀率的新实验数据。采用膨胀计法和伽马射线衰减技术进行测量,测量的温度范围对于镁为145~1244K,对于镁锂合金为293~1000K。直接测量Mg和Mg70Li30合金在... 给出关于固体和液态的镁以及含23.03at.%和30.02at.%Li的超轻镁锂合金的密度和热膨胀率的新实验数据。采用膨胀计法和伽马射线衰减技术进行测量,测量的温度范围对于镁为145~1244K,对于镁锂合金为293~1000K。直接测量Mg和Mg70Li30合金在固.液相变时的密度变化,建立体积性质与温度的关系和参考表。将所得结果与文献数据进行比较,结果表明,镁锂体系中的共晶成分不是23at.%Li。研究发现,在0~30at.%Li范围内,液态镁锂体系的摩尔体积与浓度几乎呈线性关系,和理想混合物的明显不同。 展开更多
关键词 密度 熔体 固体 镁锂合金 热膨胀 互扩散
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EDTA络合滴定法快速测定矿石中钙、镁 预览
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作者 韩晓 《中国无机分析化学》 CAS 2019年第2期54-57,共4页
试样用盐酸、硝酸、氢氟酸、高氯酸分解,在pH值为6~9时,经六次甲基四胺-铜试剂分离铁、铝、镍、钴、铅、锌、铜、镉、锰等干扰元素后,在pH=10的氨水和氯化铵缓冲溶液中,以酸性铬蓝K-萘酚绿B为指示剂,用EDTA络合滴定法测定钙镁合量;另在... 试样用盐酸、硝酸、氢氟酸、高氯酸分解,在pH值为6~9时,经六次甲基四胺-铜试剂分离铁、铝、镍、钴、铅、锌、铜、镉、锰等干扰元素后,在pH=10的氨水和氯化铵缓冲溶液中,以酸性铬蓝K-萘酚绿B为指示剂,用EDTA络合滴定法测定钙镁合量;另在氢氧化钾溶液中,用钙试剂为指示剂,以EDTA络合滴定法测定钙量,从而计算镁的含量。当样品钙高镁低或者镁高钙低时,低含量的镁量或钙量(<5%)可用电感耦合等离子体原子发射光谱(ICP-AES)法准确测定,使结果更准确。实验中对三个标准样品中的钙和镁进行多次测定,结果与认定值相符,相对标准偏差在0.69%~1.3%(n=7),加标回收率在99%~102%。方法实用性强,已经成功应用于各类矿石中钙镁的检测。 展开更多
关键词 容量法 ICP-AES 矿石
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A High-Ductility Mg–Zn–Ca Magnesium Alloy
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作者 Teng Tu Xian-Hua Chen +2 位作者 Jiao Chen Chao-Yue Zhao Fu-Sheng Pan 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第1期23-30,共8页
A new kind of Mg–2 Zn–0.6 Ca(wt%) alloy was fabricated by casting and hot extrusion as a high-ductility structural material. The extruded alloy exhibits a superior elongation of ~30%, yield strength of 130 MPa and u... A new kind of Mg–2 Zn–0.6 Ca(wt%) alloy was fabricated by casting and hot extrusion as a high-ductility structural material. The extruded alloy exhibits a superior elongation of ~30%, yield strength of 130 MPa and ultimate tensile strength of 280 MPa along the extrusion direction at room temperature. Microstructure, texture and tensile properties of the extruded alloy were investigated in details. The remarkable improvement of ductility is ascribed to the weakened basal texture, refined grains and a small number of second phase in the alloy. 展开更多
关键词 Magnesium alloy Mg–Zn–Ca High DUCTILITY EXTRUSION TEXTURE
Strength and Wear Behavior of Mg Alloy AE42 Reinforced with Carbon Short Fibers
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作者 Sabbah Ataya Naser A.Alsaleh Mohamed M.El-Sayed Seleman 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第1期31-40,共10页
In addition to the advantage of the lightweight of magnesium alloys, magnesium composites have moderate strength and elastic modulus. The proposed application of magnesium composites as diesel truck pistons makes it n... In addition to the advantage of the lightweight of magnesium alloys, magnesium composites have moderate strength and elastic modulus. The proposed application of magnesium composites as diesel truck pistons makes it necessary to assess their wear performance. Little research data have been discussed on wear behavior of Mg alloy AE42 matrix and its composites. Thus, this paper reports wear behavior of magnesium alloy AE42(Mg–Al–Mn—RE;rare earth) and its composite AE42-C, which contains 23 vol% of randomly oriented carbon short fibers. Materials characterization, including density measurements, hardness testing, microstructures investigation, and compression testing at temperatures of 25, 150,and 300 °C, were conducted. Wear tests were performed under various loads and sliding distances. Wear mechanisms were also proposed based on the examination of worn surfaces using optical microscopy and scanning electron microscopy equipped with EDX(energy-dispersive X-ray spectrometry) analysis system. The hardness of AE42-23 vol% C composite is twice the hardness of the Mg matrix alloy AE42. Significant improvements to yield stress and compressive strength at temperatures of 25, 150, and 300 °C of the composite versus the AE42 alloy are achieved. Wear resistance of the composite is improved considerably versus that of the Mg alloy AE42 at the various sliding distances. Smearing of graphite on the worn surface produces a lubricating film that delays change from mild to severe wear of the composite, especially at high loads. EDX analysis of the worn surface shows oxidation of the matrix alloy at higher wear loads, and this mechanism decreases in the presence of carbon fibers under the same loads. Abrasive wear, oxidation, and plastic deformation are the dominant wear mechanisms for the alloy matrix AE42, whereas mainly abrasive wear is the wear mechanism of AE42-23 vol% C composite under the proposed testing conditions. 展开更多
关键词 Magnesium composites CARBON short fibers COMPRESSIVE STRENGTH WEAR resistance WEAR mechanisms
Feasibility of aluminum recovery and MgAl2O4 spinel synthesis from secondary aluminum dross 预览
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作者 Yong Zhang Zhao-hui Guo +2 位作者 Zi-yu Han Xi-yuan Xiao Chi Peng 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第3期309-318,共10页
The feasibility of aluminum recovery from secondary aluminum dross by extraction with NaOH solution and the subsequent synthesis of MgAl2O4 spinel by sintering the extracted slag were studied. The extraction percentag... The feasibility of aluminum recovery from secondary aluminum dross by extraction with NaOH solution and the subsequent synthesis of MgAl2O4 spinel by sintering the extracted slag were studied. The extraction percentage of soluble aluminum from the dross reached 80% at a temperature of 353 K, liquid-to-solid ratio of 12 mL·g^-1, stirring speed of 300 r·min^-1, and an extraction time of 15 min;the hydrolysis percentage of AlN reached 40% with an extraction time of 30 min. The activation energies of the soluble aluminum and AlN extracted from the dross were 7.15 and 8.98 kJ·mol^-1, respectively, indicating that their kinetics were controlled by outer diffusion without a product layer. The extracted slag was sintered in the temperature range 1373–1773 K;MgAl2O4 spinel with a compressive strength as high as 69.4 MPa was produced in the sample sintered at 1673 K for 3 h. This value exceeds the threshold (40 MPa) prescribed by the National Standard for the Magnesia and Magnesia-alumina Refractory Bricks of China (GB/T 2275?2007). These results establish the effectiveness of aluminum recovery from secondary aluminum dross and subsequent MgAl2O4 spinel synthesis. 展开更多
关键词 SECONDARY ALUMINUM DROSS reuse extraction sintering magnesium ALUMINATE SPINEL
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锂、钠、钾、镁、钙、氯复合电解质冰冻人血清国家标准品的研制和性能评价 预览
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作者 于婷 沈敏 +1 位作者 曲守方 黄杰 《检验医学》 CAS 2019年第5期457-462,共6页
目的研制锂、钠、钾、镁、钙、氯复合电解质冰冻人血清国家标准品,并评价其性能,促进锂、钠、钾、镁、钙、氯电解质测定的标准化。方法收集含不同浓度锂、钠、钾、镁、钙、氯离子的无溶血、脂血和黄疸血清,经多重过滤、除菌后分装,制备... 目的研制锂、钠、钾、镁、钙、氯复合电解质冰冻人血清国家标准品,并评价其性能,促进锂、钠、钾、镁、钙、氯电解质测定的标准化。方法收集含不同浓度锂、钠、钾、镁、钙、氯离子的无溶血、脂血和黄疸血清,经多重过滤、除菌后分装,制备成3个水平的候选品,-70℃保存。以钾离子作为均匀性评价的特性量,采用单因素方差分析评价候选品的均匀性。以钾、钠、氯离子作为稳定性评价的特性量,采用线性回归分析评价候选品的稳定性。采用参考方法或经验证的方法定值,并计算不确定度。评估候选品、新鲜血清样本在参考方法或经验证的方法与4个常规检测系统间的互通性。结果3个水平侯选品中,钾离子的均匀性检验F值分别为1.6301、1.4986和1.0208,均<F0.05;钾、钠、氯离子在2~8℃、20~25℃和-20℃条件下,均至少可稳定30d。3个水平侯选品中,锂离子定值结果分别为(0.649±0.022)、(1.195±0.032)、(1.334±0.008)mmol/L(k=2),钠离子定值结果分别为(120.057±2.206)、(142.030±1.521)、(158.228±1.293)mmol/L(k=2),钾离子定值结果分别为(5.042±0.143)、(5.739±0.106)、(6.158±0.094)mmol/L(k=2),镁离子定值结果分别为(0.732±0.021)、(0.857±0.026)、(1.144±0.026)mmol/L(k=2),钙离子定值结果分别为(2.014±0.078)、(2.348±0.056)、(3.070±0.024)mmol/L(k=2),氯离子定值结果分别为(90.814±2.005)、(108.875±0.908)、(128.156±1.453)mmol/L(k=2)。钠、钾、镁、钙和氯离子3个水平侯选品浓度均在新鲜血清样本的95%可信区间内,互通性良好。结论制备的锂、钠、钾、镁、钙、氯复合电解质冰冻人血清国家标准品候选品均匀性、稳定性好,钠、钾、镁、钙和氯离子侯选品互通性良好,定值准确可靠,可作为国家标准品使用。 展开更多
关键词 冰冻人血清 国家标准品
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Self-lubricate and anisotropic wear behavior of AZ91D magnesium alloy reinforced with ternary Ti2AlC MAX phases
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作者 Wenbo Yu Deqiang Chen +2 位作者 Liang Tian Hongbin Zhao Xiaojun Wang 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第3期275-284,共10页
The dry sliding wear behavior of Ti2AlC reinforced AZ91 magnesium composites was investigated at sliding velocity of 0.5 m/s under loads of 10, 20, 40 and 80 N using pin-on-disk configuration against a Cr15 steel disc... The dry sliding wear behavior of Ti2AlC reinforced AZ91 magnesium composites was investigated at sliding velocity of 0.5 m/s under loads of 10, 20, 40 and 80 N using pin-on-disk configuration against a Cr15 steel disc. Wear rates and friction coefficients were registered during wear tests. Worn tracks and wear debris were examined by scanning electron microscopy, energy dispersive X-ray spectrometry and transmission electron microscopy in order to obtain the wear mechanisms of the studied materials. The main mechanisms were characterized as the magnesium matrix oxidation and self-lubrication of Ti2AlC MAX phase. In all conditions, the composites exhibit superior wear resistance and self-lubricated ability than the AZ91 Mg alloy. In addition, the anisotropic mechanisms in tribological properties of textured Ti2AlC-Mg composites were confirmed and discussed. 展开更多
关键词 TI2ALC Dry SLIDING wear Magnesium alloy Self-lubricate ability
The relative changes of a sea surface temperature in the South China Sea since the Pliocene 预览
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作者 Dongjie Bi Daojun Zhang +4 位作者 Shikui Zhai Xinyu Liu Chun Xiu Xiaofeng Liu Aibin Zhang 《海洋学报:英文版》 SCIE CAS CSCD 2019年第3期78-92,共15页
The reconstruction of sea surface temperature(SST) is a key issue in research on paleoceanography. The recently related studies are mainly concentrated on the Quaternary. The skeletons of a typical species of benthoni... The reconstruction of sea surface temperature(SST) is a key issue in research on paleoceanography. The recently related studies are mainly concentrated on the Quaternary. The skeletons of a typical species of benthonic foraminifer(Amphistegina radiata) in the top 0–375.30 m interval of Well 'Xike-1' reef core, Shidao Island, the Xisha Islands, are uniformly selected. The ratios of magnesium to calcium concentrations and other indicators are analyzed by an electron microprobe analysis(EMPA) with the purpose of estimating the paleo-SSTs since the Pliocene and further investigating the periodic change law of paleoclimate in the South China Sea(SCS).Meanwhile, the geologic significance of paleoclimatic events in the SCS is discussed with global perspectives. The results indicate that the paleo-SSTs reconstructed by the ratios of magnesium to calcium concentrations in the SCS show a general periodic trend of 'high–low–high–low' in values changes since the Pliocene. By comparison,the fluctuations of reconstructed paleo-SSTs are much stronger in the Quaternary. Moreover, the variations of the ratios of magnesium to calcium concentrations in the A. radiata skeletons have recorded a series of major paleoclimatic events since the Pliocene, of which the Quaternary glaciation events and the Arctic ice cap forming events during the late Pliocene are more significant. Thus, using the changes of the ratios of magnesium to calcium concentrations in the A. radiata skeletons from Well 'Xike-1' reef core to reflect the relative changes of paleo-SSTs is a relatively feasible and reliable way in the SCS, which is also proved by the correlation of drilling cores characteristics in this area. 展开更多
关键词 the ratios of magnesium to calcium CONCENTRATIONS benthonic FORAMINIFERA sea surface temperature PALEOCLIMATIC events
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镁硼配施对红壤烤烟镁、硼含量及经济性状的影响 预览
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作者 孙兴权 顾毓敏 +3 位作者 夏贤仁 卢晓华 王瑞宝 王全贞 《江西农业学报》 CAS 2019年第5期65-69,共5页
采用双因素随机区组试验,以红壤为对象,研究了不同水平镁、硼肥配施对烟叶镁、硼含量和经济性状的影响。结果表明,对烟叶镁含量的影响主要是镁的独立效应,烟叶硼含量除受硼独立效应的影响外,还与镁有显著的交互作用,镁-硼的交互作用在... 采用双因素随机区组试验,以红壤为对象,研究了不同水平镁、硼肥配施对烟叶镁、硼含量和经济性状的影响。结果表明,对烟叶镁含量的影响主要是镁的独立效应,烟叶硼含量除受硼独立效应的影响外,还与镁有显著的交互作用,镁-硼的交互作用在镁肥水平为180kg/hm^2时效应最大;镁对烤烟产量、产值和中上等烟比例有极显著的影响效应,硼对产值和中上等烟比例有显著的影响效应,镁、硼肥配施对烤烟产值的交互作用有显著的影响效应,其交互作用在硼肥水平为30kg/hm^2时效应最大。在供试条件下,宣威红壤烟区镁、硼肥的最佳用量和施用方法为:180kg/hm^2镁肥配施30kg/hm^2硼肥,其中,50%镁肥和100%硼肥作为基肥塘施,剩余50%镁肥于移栽后30d兑水浇施。 展开更多
关键词 烤烟 镁-硼互作 红壤 经济性状
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尿样保存温度和时间对尿中钙、镁检测的影响
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作者 李丽丽 陈振玲 +2 位作者 刘铁兵 刘永锁 徐先发 《中国职业医学》 CAS 北大核心 2019年第2期221-224,共4页
目的探讨尿样采集后保存温度和时间对尿中钙、镁检测结果的影响。方法采集5名健康志愿者尿液,分装密封后分别在室温、4℃和-20℃条件下保存不同时间,采用原子吸收火焰光谱法测定尿中钙和镁的质量浓度。结果尿样室温保存8 h时,钙、镁质... 目的探讨尿样采集后保存温度和时间对尿中钙、镁检测结果的影响。方法采集5名健康志愿者尿液,分装密封后分别在室温、4℃和-20℃条件下保存不同时间,采用原子吸收火焰光谱法测定尿中钙和镁的质量浓度。结果尿样室温保存8 h时,钙、镁质量浓度变异率<2.00%;4℃保存15 d时,钙、镁质量浓度变异率<6.00%;-20℃保存60 d时,钙、镁质量浓度变异率<5.00%。结论尿样采样后的保存温度和保存时间可影响钙、镁检测结果;尿样采样后尽快分装低温保存有利于保证检测结果的准确性。 展开更多
关键词 尿液 保存温度 保存时间 浓度
Effects of trace Cr on as-cast microstructure and microstructural evolution of semi-solid isothermal heat treatment ZC61 magnesium alloy
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作者 Xiao-feng Huang Ya-jie Ma +2 位作者 Qiao-qiao Zhang Lang-lang Wei Jian-qiao Yang 《中国铸造:英文版》 SCIE 2019年第1期53-62,共10页
The content and kind of trace elements in magnesium alloys have important effects on their ascast and semi-solid microstructures. In this research work, effects of trace Cr on as-cast and semi-solid microstructures of... The content and kind of trace elements in magnesium alloys have important effects on their ascast and semi-solid microstructures. In this research work, effects of trace Cr on as-cast and semi-solid microstructures of ZC61 magnesium alloy were investigated by metal mold casting and semi-solid isothermal heat treatment. The results show that the addition of Cr can refine the α-Mg phase without generating a new phase, noticeably change the eutectic phase, and decrease the average size of solid particles at the same isothermal heat treatment conditions. Non-dendritic microstructures of all alloys are constituted of α1-Mg phases, α2-Mg phases and eutectic phases after water quenching. With isothermal temperature increased or holding time prolonged, the eutectic microstructure(α-Mg+MgZn2+CuMgZn) at the grain boundaries in as-cast alloy is melted preferentially and then turned into semi-solid non-dendritic microstructure by processes of initial coarsening, microstructure separation, spheroidizing and final coarsening. Especially when the ZC61-0.1 Cr alloy was treated at 585 ℃ for 30 min, the ideal non-dendritic microstructure can be obtained, and the corresponding solid particle size and shape factor were 37.5 μm and 1.33, respectively. The coarsening process of solid α-Mg phase at higher temperature or longer time, which is affected by both combining growth and Ostwald ripening mechanism, is refrained when Cr is added to the ZC61 alloy. 展开更多
关键词 ZC61 magnesium alloy CR content SEMI-SOLID isothermal heat treatment NON-DENDRITIC microstructure MICROSTRUCTURAL evolution
Effect of alloying elements on magnesium alloy damping capacities at room temperature 预览
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作者 Di-qing Wan Ying-lin Hu +3 位作者 Shu-ting Ye Zhu-min Li Li-li Li Yi Huang 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第6期760-765,共6页
Alloying is a good approach to increasing its strength but leads to a reduction of damping to pure magnesium.Classifying the alloying characteristics of various alloying elements in magnesium alloys and their combined... Alloying is a good approach to increasing its strength but leads to a reduction of damping to pure magnesium.Classifying the alloying characteristics of various alloying elements in magnesium alloys and their combined effects on the damping and mechanical properties of magnesium alloys is important.In this paper,the properties of the Mg-0.6wt%X binary alloys were analyzed through strength measurements and dynamic mechanical analysis.The effects of foreign atoms on solid-solution strengthening and dislocation damping were studied comprehensively.The effect of solid solubility on damping capacity can be considered from two perspectives:the effect of single solid-solution atoms on the damping capacities of the alloy,and the effect of solubility on the damping capacities of the alloy.The results provide significant information that is useful in developing high-strength,high-damping magnesium alloys.This study will provide scientific guidance regarding the development of new types of damping magnesium alloys. 展开更多
关键词 magnesium alloys high-damping HIGH-STRENGTH ALLOYING
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Friction stir welding of pure magnesium and polypropylene in a lap-joint configuration:Microstructure and mechanical properties 预览
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作者 Amirhossein Moghanian Moslem Paidar +1 位作者 Seyyed Salman Seyedafghahi Olatunji Oladimeji Ojo 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第6期766-774,共9页
A hybrid joint with a satisfactory mixture of pure magnesium and polypropylene(PP)was achieved via friction stir joining(FSW)in a lap-joint configuration.The tool rotational and travel speeds used in this work were 50... A hybrid joint with a satisfactory mixture of pure magnesium and polypropylene(PP)was achieved via friction stir joining(FSW)in a lap-joint configuration.The tool rotational and travel speeds used in this work were 500–700 r/min and 50–100 mm/min,respectively.The mechanical properties and microstructural analysis of the resultant hybrid Mg/PP joint were examined.The results show that the maximum tensile shear strength(22.5 MPa)of the joint was attained at 700 r/min and 75 mm/min due to the optimum percentage fraction of mechanical interlocking(48%)and the presence of magnesium oxide.The interfacial joint center exhibits the maximum microhardness values because of the presence of refined and intertwined Mg fragments and density dislocations in the matrix of the PP.The joint failed via two different modes:interfacial line and weld zone fractures,respectively. 展开更多
关键词 welding microstructure PURE MAGNESIUM POLYPROPYLENE ROTATIONAL speed
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Mg-O2和Mg-CO2预混气燃烧特性及热声振荡的数值模拟研究
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作者 杨亚晶 谢伟 魏衍举 《推进技术》 EI CAS CSCD 北大核心 2019年第2期363-375,共13页
基于金属镁在高超声速飞行器及火星探测器上的应用,为探讨金属燃料在不同氧化剂环境中的燃烧特性及热声不稳定性机理,开展了数值模拟研究。考虑镁蒸气与O2和CO2两种氧化剂的剧烈反应区,构建了预混燃烧的二维燃烧室模型,详细探讨了预混... 基于金属镁在高超声速飞行器及火星探测器上的应用,为探讨金属燃料在不同氧化剂环境中的燃烧特性及热声不稳定性机理,开展了数值模拟研究。考虑镁蒸气与O2和CO2两种氧化剂的剧烈反应区,构建了预混燃烧的二维燃烧室模型,详细探讨了预混气当量比、预混气初温及入口速度等对燃烧特性及热声振荡特性的影响规律,并与CHEMKIN计算结果进行了比较分析。结果表明,较高的当量比下燃烧室的燃烧速率更快,燃烧平衡温度更高,此外增加预混气初温能加快燃烧室燃烧速率,而更高的入口速度会使燃烧室的压力振荡从低频高振幅振荡向高频低振幅振荡转化。燃烧室的压力振荡同时存在轴向振荡和径向振荡,振荡曲线为高频振荡和低频振荡的不同组合。入口速度对燃烧室压力振荡有较大影响,入口速度越快,振荡频率越高,而声压级越低。此外,预混气当量比和预混气初温对燃烧室的压力振荡也有一定影响。 展开更多
关键词 金属燃料 燃烧机理 热声振荡
饲料镁和鲈鱼幼鱼的生长及鱼体镁含量相关性研究 预览
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作者 张崇英 刘伟 宋金秋 《中国饲料》 北大核心 2019年第2期63-67,共5页
为研究饲料中不同镁含量对鲈鱼(Lateolabrax japonicus)的影响,试验在基础饲料中分别添加0、500、1250、3750、5250、8750mg/kgMgSO4,配制镁含量分别为167、284、491、959、1327、1759mg/kg的6种试验饲料,饲养初始体重为(12.31±0.0... 为研究饲料中不同镁含量对鲈鱼(Lateolabrax japonicus)的影响,试验在基础饲料中分别添加0、500、1250、3750、5250、8750mg/kgMgSO4,配制镁含量分别为167、284、491、959、1327、1759mg/kg的6种试验饲料,饲养初始体重为(12.31±0.02)g的鲈鱼56d。结果显示:日粮中适当添加镁显著影响鲈鱼的增重率、特定生长率和饲料效率(P<0.05),其中D4组(镁含量959mg/kg)鲈鱼的增长率和特定生长率均显著大于其他各组(P<0.05)。饲料镁含量显著影响鲈鱼全鱼水分(P<0.05)。随着饲料镁含量增加,肝脏中天冬氨酸转氨酶(GOT)和丙氨酸转氨酶(GPT)呈下降趋势,GOT与GPT比值和肝脏谷氨酸脱氢酶(GDH)也出现显著变化(P<0.05)。通过回归分析增重率得出,本试验中鲈鱼生长的最适饲料镁含量为846mg/kg。 展开更多
关键词 鲈鱼 生长性能 鱼体成分 肝功能
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镁对原位晶化催化剂抗镍性能的影响 预览
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作者 黄蕾 张莉 《石油炼制与化工》 CAS CSCD 北大核心 2019年第3期63-67,共5页
在原位晶化催化裂化催化剂的制备过程中,采用浸渍法引入具备抗镍功能的镁对其进行改性,再对其进行重金属镍污染;借助N2吸附-脱附等温线、红外光谱、X射线衍射等手段对镁改性后催化剂样品进行表征;在固定流化床装置考察镁对原位晶化催化... 在原位晶化催化裂化催化剂的制备过程中,采用浸渍法引入具备抗镍功能的镁对其进行改性,再对其进行重金属镍污染;借助N2吸附-脱附等温线、红外光谱、X射线衍射等手段对镁改性后催化剂样品进行表征;在固定流化床装置考察镁对原位晶化催化剂抗镍性能的影响。结果表明,在镍污染条件下,当催化剂上镁负载量(w)为1.0%时,与未负载镁时相比,微反活性下降19百分点,干气和焦炭产率分别降低0.81百分点和4.36百分点,重油转化率和C5+汽油收率变化不大,说明将适量的镁负载于原位晶化催化剂上能够在一定程度上提高催化剂抗镍性能。 展开更多
关键词 原位晶化催化剂 抗镍
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Recent Research on the Deformation Behavior of Particle Reinforced Magnesium Matrix Composite: A Review
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作者 Kun-Kun Deng Cui-Ju Wang +1 位作者 Kai-Bo Nie Xiao-Jun Wang 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第4期413-425,共13页
Particle reinforced magnesium matrix composite(PMMC) possesses the merits of high specific strength, high specific modulus, better dimensional stability, good wear resistance and lower production cost, which is though... Particle reinforced magnesium matrix composite(PMMC) possesses the merits of high specific strength, high specific modulus, better dimensional stability, good wear resistance and lower production cost, which is thought as a promising material in the field of aerospace, automobile, electronic communication, etc. To eliminate the casting defect, the PMMC is usually experienced hot deformation process. The present paper mainly focuses on the deformation behavior of PMMCs. First, the development of PMMCs based on particle size is introduced. Then, the hot deformation technology and deformation mechanism of PMMCs at elevated temperature are given and analyzed, respectively. After reviewing the dynamic recrystallization and texture of PMMCs, its future development is suggested based on the current research progress. 展开更多
关键词 MAGNESIUM matrix composite PARTICLE Hot DEFORMATION DEFORMATION mechanism RECRYSTALLIZATION
Effect of Different Scale Precipitates on Corrosion Behavior of Mg–10Gd–3Y–0.4Zr Alloy
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作者 Shuang Yu Rui-Ling Jia +3 位作者 Tao Zhang Fu-Hui Wang Jian Hou Hui-Xia Zhang 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第4期433-442,共10页
A large amount of directional and willow-like β’ phase was precipitated in Mg-10 Gd-3 Y-0.4 Zr(GW103 K) alloy after solution treatment and subsequently aged treatment(T6). In order to explore the effect of the preci... A large amount of directional and willow-like β’ phase was precipitated in Mg-10 Gd-3 Y-0.4 Zr(GW103 K) alloy after solution treatment and subsequently aged treatment(T6). In order to explore the effect of the precipitates on the corrosion behavior of the GW103 K alloy, the alloy was subjected to solution treatment(T4) at 773 K for 4 h at first, subsequently aged at 498 K for 193 h(T6). The microstructure evolution of the GW103 K alloy after this treatment was investigated by scanning electron microscopy and transmission electron microscopy. The high-angle annular detector dark-field scanning transmission electron microscopy was used to observe the typical corrosion morphologies of the nanoscale precipitation phases(β’) in the T6-treated alloy. The corrosion rate was measured by potentiodynamic polarization test. Combining with the potential measurement results by scanning Kelvin probe force microscopy, the effects of the skeleton-like Mg24(Gd,Y)5 andf precipitates on the corrosion behavior of GW103 K alloy were explored. The results showed that the corrosion rate of the GW103 K alloy in different conditions was ranked as: as-cast alloy> T4-treated alloy> T6-treated alloy,attributing to the fact that the relative potential differences of skeleton-like Mg24(Gd,Y)5 were lower than those of the matrix, therefore Mg24(Gd, Y)5 phase formed micro-galvanic coupling with the matrix and corrosion dissolution occurred.The nanoscale β’ precipitates in T6-treated alloy can retard the cathodic process. 展开更多
关键词 MAGNESIUM ALLOY AGING PRECIPITATES Corrosion Potential difference Transmission electron microscopy(TEM)
Catalytic effect of SrTiO3 on the hydrogen storage behaviour of MgH2 预览
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作者 M.S.Yahya M.Ismail 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第1期46-53,共8页
The effects of Sr TiO3 on the hydrogen storage properties of MgH2 have been studied for the first time.The onset dehydrogenation temperature of the MgH2-10 wt% SrTiO3 is found to be 275℃, which is 55℃ lower as compa... The effects of Sr TiO3 on the hydrogen storage properties of MgH2 have been studied for the first time.The onset dehydrogenation temperature of the MgH2-10 wt% SrTiO3 is found to be 275℃, which is 55℃ lower as compared to the as-milled MgH2. The composite is able to absorb 4.3 wt% of hydrogen in 60 min instead of 1.1 wt% for the as-milled Mg H2. Meanwhile, the composite is able to release 5.3 wt% of hydrogen in 17 min compared to 1.9 wt% by the as-milled Mg H2 at 320℃. The calculated Eaof the Mg H2-10 wt% SrTiO3 is 109 k J/mol, which is 26.3 kJ/mol lower than the calculated Eaof the as-milled MgH2. The Sr TiO3 is not decomposed during the ball milling and the re/dehydrogenation processes. The catalytic effect shown by the SrTiO3 is owing to its ability to change the physical structure of the MgH2 particles during the ball milling process. 展开更多
关键词 Hydrogen storage MAGNESIUM HYDRIDE CATALYTIC effect SORPTION properties
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