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Determination of Ge in Au alloys using sodium hypophosphite and potassium iodate potentiometric titration method

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Rare Metals 2020年第12期39卷 1492-1496页

作者： Shou-Li Han Xiao-Tang He Jun-Mei Guo Zhao-Ying Ren Li-Ya Zhu Liang-Wei Chen qing-nan shi Jia-Hong Yi School of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals Sino-Platinum Metals Resources(Yimen)Co.Ltd.Yimen651100China

This paper presents a new method of determining Ge in AuGe alloys by potassium iodate(KIO3)potentiometric titration when Ge(Ⅱ)and Au(0)are simultaneously reduced from Ge(Ⅳ)and Au(Ⅲ)by sodium hypophosphite rather than by distillation *** influences of such conditions as the reduction acidity,the dosage of sodium hypophosphite and the reduction time on the determination of Ge were *** in AuGe alloys such as AuGe_(12),AuGeNi_(12-2),AuAgGe_(18.8-12.5),and AuAgGeNi_(43.8-6-0.2)was measured with the relative standard deviation(RSD)of 0.10%-0.31%and the recoveries of added standard Ge in sample of 99.40%-100.40%under the conditions of 0.40-0.80 mol·L^(-1)HCl,3.3 mol·L^(-1)H^(3)PO^(4),15 g sodium hypophosphite,and reduction time of40 *** new method presented is of high accuracy in results,good stability and sensibility in end-point,and easy operation and strong selectivity of determination.

关键词： Ge determination AuGe alloy Sodium hypophosphite Potassium iodate Potentiometric titration

Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang qing shi Guofan Zhang Yuxuan Zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

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倾斜空区顶板三铰拱轴曲线结构自稳分析

东北大学学报（自然科学版） 2015年第11期36卷 1629-1632,1642页

作者：翟会超任凤玉南世卿东北大学资源与土木工程学院辽宁沈阳110819 河北钢铁集团矿山设计有限公司河北唐山063000

研究发现动采应力再分布使空区顶板在失稳前两拐角处形成塑性铰区,承载机构转为充分自稳的三铰拱形.针对这一特点,提出将空区顶板近似为半跨的三铰拱轴曲线结构,并建立以空区跨度L、拱失f、顶板岩层载荷q(x)为变量的力学模型,推导冒落... 详细信息

研究发现动采应力再分布使空区顶板在失稳前两拐角处形成塑性铰区,承载机构转为充分自稳的三铰拱形.针对这一特点,提出将空区顶板近似为半跨的三铰拱轴曲线结构,并建立以空区跨度L、拱失f、顶板岩层载荷q(x)为变量的力学模型,推导冒落线方程y(x)和拱轴压力N(x)方程,分析空区顶板的稳定性和冒落线形式,并计算空区的临界跨度和临界暴露面积.以排山楼金矿空区为例,利用模型得出活动延深方向临界跨度70 m,走向140 m,临界暴露面积7 693 m2.提出禁止间柱回采,及时充填空区的治理方法,保障井下安全.

关键词：倾斜空区顶板三铰拱轴稳定性分析临界跨度空区治理

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急倾斜厚大矿体矿房阶段爆破技术

东北大学学报（自然科学版） 2017年第10期38卷 1486-1490页

作者：翟会超任凤玉南世卿东北大学资源与土木工程学院辽宁沈阳110819 河北钢铁集团矿山设计有限公司河北唐山063000

针对司家营南区大规模落矿的安全性问题,提出阶段凿岩侧向爆破方案.该方案包括利用上向扇形炮孔爆破形成堑沟,下向垂直深孔爆破侧向崩矿,具有工程量小、机械化程度高、管理简单等优点.利用FLAC3D研究阶段爆破技术,对塑性区、监测点振速... 详细信息

针对司家营南区大规模落矿的安全性问题,提出阶段凿岩侧向爆破方案.该方案包括利用上向扇形炮孔爆破形成堑沟,下向垂直深孔爆破侧向崩矿,具有工程量小、机械化程度高、管理简单等优点.利用FLAC3D研究阶段爆破技术,对塑性区、监测点振速和应力场的动态模拟计算验证了大规模爆破起爆顺序的合理性和减震性,以及爆破对围岩或充填体的非破坏性.同时,研究VCR法开掘切割天井技术,采取中心与交错正菱形布设炮孔,孔间分5段起爆,保证了阶段爆破自由空间的形成.

关键词：急倾斜厚大矿体垂直深孔爆破数值模拟 FLAC3D VCR法

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田兴铁矿1#主井工作面注浆治水技术研究

矿冶工程 2014年第3期34卷 26-28页

作者：翟会超南世卿河北钢铁集团矿山设计有限公司河北唐山063000

针对田兴铁矿1#主井水文地质实际条件,采用止浆垫注浆技术进行工作面治水。通过对注浆参数的合理计算与设计,以及对注浆施工的有效管理,使该技术在1#主井注浆治水过程中得到成功应用,掘进工作面出水量降到10.39 m3/h,为掘砌作业提供了... 详细信息

针对田兴铁矿1#主井水文地质实际条件,采用止浆垫注浆技术进行工作面治水。通过对注浆参数的合理计算与设计,以及对注浆施工的有效管理,使该技术在1#主井注浆治水过程中得到成功应用,掘进工作面出水量降到10.39 m3/h,为掘砌作业提供了安全保障。

关键词：止浆垫注浆治水

Separation of the ionospheric and thermospheric contributions in the data from the Triple Ionosophere Photo Meter onboard the Feng-Yun 3E satellite

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Science China Earth Sciences 2025年第1期68卷 172-184页

作者： Fang JIANG Tian MAO Jin-Song WANG Xiu-qing HU Xiao-Xin ZHANG Liping FU nan JIA Tianfang WANG National Space Science Center Chinese Academy of Sciences Beijing Key Laboratory of Space Environment Exploration Key Laboratory of Environmental Space Situation Awareness Technology National Satellite Meteorological Center China Meteorological Administration

The Triple Ionosphere Photo Meter （TRIPM） is a far ultraviolet nadir-view photometer that is onboard the secondgeneration,polar-orbiting Chinese meteorological satellite Feng-Yun 3E （FY-3E）,which was launched on July 5,*** has three channels,and each is used to measure different types of emissions:（1） 135.6 nm airglow produced by the recombination of the O+ions and electrons in the absence of sunlight （nighttime channel）;（2） 135.6 nm airglow from the OI when sunlight is present （daytime/dusk-dawn 135.6 nm channel）;and （3） Airglow in the N2LBH of the TRIPM （daytime/dusk-dawn N2LBH channel）.FY-3E is a satellite operating in the early morning ***,the data are mostly distributed on the dawndusk side or at times when the solar zenith angle is relatively *** this study,combined with simulation calculations,the data are *** further explore the application value of the data products,a model is used to separate the ionospheric radiative recombination contribution from the thermosphere photoelectron impact excitation contribution in the data from the daytime/dusk-dawn 135.6 nm *** approach not only improves the accuracy of O/N2derived from the 135.6 nm channel and N2LBH channel but also provides the ionospheric 135.6 nm radiance at the same time as the *** results show that the 135.6 nm radiance originating from the combination of O+and electrons extracted from the measurement data exhibits similar equatorial anomaly peak structure characteristics and seasonal variations as the corresponding GPS total electron content （TEC） *** the other hand,the separated 135.6 nm radiance generated from the thermosphere photoelectron collision excitation does not contain radiative recombination contributions;thus,the ionosphere influence is greatly avoided when the O/N2is obtained.

关键词： Far ultraviolet 135.6 nm emission intensity Photoelectron impact excitation Radiative recombination excitation

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Rheological characteristics of injection molded titanium alloys powder

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Transactions of Nonferrous Metals Society of China 2013年第9期23卷 2605-2610页

作者：王家惠史庆南吴承玲席健昆明理工大学城市学院昆明650051 昆明理工大学材料科学与工程学院昆明650093

Ti-6Al-4V alloy powder was taken as raw material. 60%（mass fraction） paraffin, 35%low density polyethylene and 5%stearic acid were employed as binders to prepare injection feedstocks. Capillary rheometer was adopted to determine the rheological parameters and to analyze the rheological properties of the feedstocks at different milling time, powder loading and temperature. It is indicated through the results that the viscosity increases and the value of n decreases with the increase of milling time. The more the powder loading is, the higher the viscosity is. The empirical formula on the relationship between the viscosity and the powder loading is： ηr=η/ηb=A（1-Ф/Фmax）/^- m . The value m is calculated as 0.33. The flow activation energy Ea decreases with the increase of shear rate.

关键词： injection molding titanium alloy feedstock rheological properties

Tailor-made high elasticity and low-hysteresis hydrogels based on asymmetric H-bonding crosslinking for wearable applications

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Science China Chemistry 2025年

作者： Xiaofang shi nan shi Miaomiao Dang Chengyu Ji Yingjie Li Peiyi Wu Zhiguo Hu Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals Henan Engineering Laboratory of Chemical Pharmaceutical and Biomedical Materials School of Chemistry and Chemical Engineering Henan Normal University State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Chemistry Chemical Engineering and Biotechnology & Center for Advanced Low-dimension Materials Donghua University

The conventional method of fabricating hydrogels constantly confronts the conflict between elasticity and toughness, limiting their repetitive application. Achieving the desired elasticity through a simple and low-cost approach is a significant challenge for hydrogels, particularly through rational molecular design. Here, low-hysteresis and high-toughness hydrogels are developed from the design of a new feature monomer, N-acryloylethylsemicarbazide (NACE). Based on a concept of “asymmetric Hbonding design”, the unique double and triple H-bonding of NACE can result in a novel asymmetric crosslinking polymer with alternating strong and weak H-bonding regions. The NACE is copolymerized with acrylamide (AM) to regulate the mechanical properties of hydrogel via H-bonding density. The P(NACE-AM) ionic hydrogels are obtained simply and rapidly via one-step photopolymerization without a chemical cross-linking agent. The P(NACE-AM) hydrogels combine superb mechanical elasticity and toughness, and excellent ionic conductivity, showing great potential as durable ionic conductive devices for wearable utilization.

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充填采矿新型胶结材料流变特性研究

中国矿业 2013年第1期22卷 108-111页

作者：夏德胜高谦南世卿河北钢铁集团矿业有限公司河北唐山063000 北京科技大学北京100083

充填料浆的流变特性成为充填采矿中管路输送能力和输送过程中安全和可靠性的关键环节,与胶结材料性质密切相关。本研究对石人沟铁矿尾砂进行水泥与新型胶结材料流变特性的试验对比分析,揭示不同浓度条件下砂浆流变特性随胶砂比的变化规... 详细信息

充填料浆的流变特性成为充填采矿中管路输送能力和输送过程中安全和可靠性的关键环节,与胶结材料性质密切相关。本研究对石人沟铁矿尾砂进行水泥与新型胶结材料流变特性的试验对比分析,揭示不同浓度条件下砂浆流变特性随胶砂比的变化规律,总结新型胶结材料流变参数对胶砂比的敏感度来反映料浆的流动性和稳定性,并对料浆浓度的不同变化范围进行统计分析和参数评价,缩小料浆浓度控制范围,实现减阻输送,确保高浓度料浆的安全、大流量和经济输送。

关键词：充填采矿新型胶结材料管路输送流变特性试验研究