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Evolution Behavior of γ-Al_(3.5)FeSi in Mg Melt and a Separation Method of Fe from Al–Si–Fe Alloys

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Acta Metallurgica Sinica(English Letters) 2018年第1期31卷 48-54页

作者： Tong Gao Zeng-Qiang Li Yao-xian Zhang xiang-fa Liu Key Laboratory for Liquid–Solid Structural Evolution and Processing of Materials Ministry of Education Shandong University

The recycling of high Fe-content Al-Si alloys is a green industry. Eliminating the harmful effect of Fe, achieving the separation of Al and Fe is one of the key problems. Different from traditional methods for iron removal, a novel method using magnesium melt to separate Al and Fe is proposed. By introducing Al-14Si-5Fe alloy into Mg melt, it was found that the γ-Al3.5FeSi phase evolves to Al3SiFe3.5 and Al5Fe2 through the melting and solidification process. Compared with the primary Al-rich γ-Al3.5FeSi phase, the formation of Fe-rich A13SiFe3.5 is quite beneficial for the separation of Al and Fe. Mg-Si-Al and Mg-Si-Fe alloys can be obtained at the top and bottom of the cooled ingot, respectively. The results in this study provide meaningful suggestions for recycling scrap Al-Si-Fe materials.

关键词： Al-Si-Fe Mg melt Fe-rich phase evolution Separation

Medical Image Compression by Applying 3D DWT in PACS

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Wuhan University Journal of Natural Sciences 1999年第3期4卷 313-318页

作者： wang Si-xian Li Fei-peng Zeng fa-long Liao Meng-yang Li Hui Wuhan Univ Wuhan China

The process of image compression in a practical Picture Archiving and Communication System (PACS) was discussed with detail. To fully reduce the inter-slice correlation existing in the volumetric image sets generated by CT and MR, 3D Discrete Wavelet Transformation (DWT) was introduced in our application. Instead of using a fixed quantizer of lossless low frequency and distinct loss of high frequency, an adaptive quantizer was devised taking MSE as the performance index. In the low frequency subband, DPCM was replaced withS+P transform to facilitate coding computation. Compared with JPEG or 2D DWT, our method is 20%–50% more efficient. Furthermore, preliminary tests showed that 33 dB may be the maximal distortion threshold for CT images.

关键词： PACS 3D DWT S+P transformation optimal bit allocation maximal distortion threshold

Carbon nanotube enhanced water-based drilling fluid for high temperature and high salinity deep resource development

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Petroleum Science 2022年第2期19卷 916-926页

作者： Jing-Ping Liu xian-fa Zhang Wen-Chao Zhang Kai-He Lv Yin-Rui Bai Jin-Tang wang xian-Bin Huang Jia-Feng Jin Jin-Sheng Sun College of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China CNPC Engineering Technology R&D Company Limited Beijing 102206China

Drilling fluids face failure during drilling deep reservoir with high temperature and high *** experimental results show that high temperature and salinity reduce the negative charge on the surface of bentonite in the drilling fluid and cause the coalescence of bentonite *** a result,the particles coalesce,the grid structure is destroyed,and the rheological properties,rock-carrying capacity and filtration properties are *** resolve the foregoing,in this study,0.05-wt%carbon nanotubes are introduced into a 4%bentonite drilling fluid under conditions where the temperature and concentration of added Na Cl reach 180°C and 10 wt%,*** carbon nanotubes adsorb on the bentonite surface and increase the space among bentonite *** steric hindrance prevents the coalescence of bentonite in high temperature and high salt *** bentonite maintains the small size distribution of bentonite and supports the bentonite grid structure in the drilling *** a result,the rock-carrying capacity of the drilling fluid increases by 85.1%.Moreover,the mud cake formed by the accumulation of small-sized bentonite particles is dense;consequently,the filtration of bentonite drilling fluid reduced by 30.2%.

关键词： High temperature Water-based drilling fluid High salinity Carbon nanotube Deep resources

Biodegradable Polymers,History Tells Polymer Science's Fortune

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Chinese Journal of Polymer Science 2022年第5期40卷 431-432页

作者： xian-Hong wang Changchun Institute of Applied Chemistry CAS

Origin and Overview Biodegradable polymer,according to the International Union of Pure and Applied Chemistry(IUPAC),is defined as“polymer susceptible to degradation by biological activity,with the degradation accompanied by a lowering of its molar mass”.More specifically,biodegradable polymer should ultimately degrade into CO_(2) and water.

关键词： polymer IUPAC molar

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

Soil properties and corn(Zea mays L.)production under manure application combined with deep tillage management in solonetzic soils of Songnen Plain,Northeast China

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Journal of Integrative Agriculture 2016年第4期15卷 879-890页

作者： MENG Qing-feng LI Da-wei ZHANG Juan ZHOU Lian-ren MA xian-fa wang Hong-yan wang Guang-cheng School of Resources and Environment Northeast Agricultural UniversityHarbin 150030P.R.China Center of Zhaozhou County on Popularization of Agricultural Technology zhaozhou 166400P.R.China

Poor soil structure and nutrients, excessive exchangeable Na＋, high pH as well as low enzyme activities are common in the solonetz, and significantly restrict corn （Zea mays L.） production. Cattle manure application combined with deep tillage is an important management practice that can affect soil physico-chemical properties and enzyme activities as well as corn yield in the solonetz. Field experiments were carried out in a randomized complete block design comprising four treatments： Corn with conventional tillage was used as a control, and corn with manure application combined with deep tillage as well as film mulching and aluminium sulfate were used as the experimental treatments, respectively. The relationship between corn yield and measured soil properties was determined using stepwise regression analysis. Manure application combined with deep tillage management was more effective than conventional tillage for increasing corn yield and for improving soil properties in the solonetz. The highest corn yield was obtained in the treatments with manure application＋deep tillage＋plastic film mulching （11 472 and 12 228 kg ha-l）, and increased by 38 and 43% comparing with the control treatment （8 343 and 8 552 kg ha-1） both in the 2013 and 2014 experiments, respectively. Using factor analysis, three factors were obtained, which represented soil fertility status, soil saline-alkaline properties and soil structural properties both in the 2013 and 2014 experiments, respectively. Manure and deep tillage management resulted in two distinct groups of soil properties：（1） soils with manure application combined with deep tillage and （2） soils with conventional tillage. Stepwise regression analysis showed that corn yield was significantly and positively correlated to urease and available P, as well as negatively correlated to pH, electrical conductivity （EC）, exchange sodium percentage （ESP）, and bulk density （Pb）. We concluded that Pb was dominant factor for corn yield on the b

关键词： cattle manure deep tillage corn yield solonetz

Tensile properties and fracture reliability of a glass-coated Co-based amorphous microwire

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International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 583-588页

作者： Xiao-dong wang Huan wang Hong-xian Shen fa-xiang Qin Da-wei Xing Jing-shun Liu Dong-ming Chen Jian-fei Sun School of Materials Science and Engineering Harbin Institute of Technology 1D Nanomaterials Group National Institute for Material Science

Co68.15Fe4.35Si12.25B15.25 （at%） amorphous microwires with a smooth surface and a circular cross-section were fabricated by the glass-coated melt spinning method. Their mechanical properties were evaluated through tensile tests of the glass-coated amorphous mi-crowires, and their fracture reliability was estimated using two-and three-parameter Weibull analysis. X-ray diffraction and transmission electron microscopy results showed that these glass-coated Co-based microwires were mostly amorphous. The coated Co-based microwires exhibit a tensile strength of 1145 to 2457 MPa, with a mean value of 1727 MPa and a variance of 445 MPa. Weibull statistical analysis showed that the tensile two-parameter Weibull modulus of the amorphous microwires is 4.16 and the three-parameter Weibull modulus is 1.61 with a threshold value as high as 942 MPa. These results indicate that the fabricated microwires exhibit good tensile properties and fracture reliability, and thus appear to be good candidates for electronics reliability engineering applications.

关键词： cobalt alloys amorphous alloys glass fracture tensile testing

Effects of Mineral Composition and Microstructure on Crack Resistance of Sintered Ore

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Journal of Iron and Steel Research International 2006年第4期13卷 9-12页

作者： YING Zi-wei JIANG Mao-fa XU Li-xian School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China

Vickers indentation test was used to study the effects of mineral composition and microstructure on crack resistance of sintered ore, and the initiation and propagation of cracks in different minerals contained in sintered ore were examined. The results indicate that the microstructure of calcium ferrites is a major factor influencing crack resistance of sintered ore. Finer grain size of calcium ferrite will lead to higher cracking threshold and better crack resistance of sintered ore. The formation of calcium ferrite with fine grain size during sintering process is favorable for crack resistance of sintered ore.

关键词： calcium ferrite crack fracture toughness cracking threshold

Etching oxide overlayers of NiFe phosphide to facilitate surface reconstruction for oxygen evolution reaction

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Green Energy & Environment 2022年第3期7卷 365-371页

作者： Tehua wang xian-Zhu Fu Shuangyin wang College of Materials Science and Engineering Shenzhen UniversityShenzhen518055China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen518060China State Key Laboratory of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082China

Transition-metal phosphides have been of concern as efficient electrocatalysts for oxygen evolution reaction(OER)due to its high conductivity and earth-abundance ***,oxide overlayers formed on their surface by spontaneously atmospheric oxidation are usually neglected,thus confusing the establishment of structure–performance ***,we successfully etched the oxide overlayers of NiFe phosphide(NiFeP)by a dielectric barrier discharge(DBD)plasma technique,aiming to reveal the influence of the oxide overlayers on its electrocatalytic performance for *** is found that etching the oxide overlayers can accelerate the surface reconstruction process of NiFeP and facilitate the formation of metal hydroxides,which are key intermediate phases for ***,the etched NiFeP-DBD material shows remarkably enhanced OER activity with an overpotential of 265 mV at a current density of 10 mA cm^(-2).The finding of this work probably brings a significant impact to understand the structure–performance relationship of metal phosphide in electrooxidation reaction.

关键词： surface oxide evolution