烧结铁矿中FeO含量对其在富氢高炉中还原行为的影响

Japan started the national project “COURSE 50” for CO₂ reduction in the 2000s. This project aimed to establish novel technologies to reduce CO₂ emissions with partially utilization of hydrogen in blast furnace-based ironmaking by 30% by around 2030 and use it for practical applications by 2050. The idea is that instead of coke, hydrogen is used as the reducing agent, leading to lower fossil fuel consumption in the process. It has been reported that the reduction behavior of hematite, magnetite, calcium ferrite, and slag in the sinter is different, and it is also considerably influenced by the sinter morphology. This study aimed to investigate the reduction behavior of sinters in hydrogen enriched blast furnace with different mineral morphologies in CO–CO₂–H₂ mixed gas. As an experimental sample, two sinter samples with significantly different hematite and magnetite ratios were prepared to compare their reduction behaviors. The reduction of wustite to iron was carried out at 1000, 900, and 800°C in a CO–CO₂–H₂ atmosphere for the mineral morphology-controlled sinter, and the following findings were obtained. The reduction rate of smaller amount of FeO led to faster increase of the reduction rate curve at the initial stage of reduction. Macro-observations of reduced samples showed that the reaction proceeded from the outer periphery of the sample toward the inside, and a reaction interface was observed where reduced iron and wustite coexisted. Micro-observations revealed three layers, namely, wustite single phase in the center zone of the sample, iron single phase in the outer periphery zone of the sample, and iron oxide-derived wustite FeO and iron, or calcium ferrite-derived wustite 'FeO' and iron in the reaction interface zone. A two-interface unreacted core model was successfully applied for the kinetic analysis of the reduction reaction, and obtained temperature dependent expressions of the chemical reaction coefficients from each mineral phases.     

Mg和La对Ca–Ti 处理钢中夹杂物演变和组织的影响

The evolution of inclusions and the formation of acicular ferrite (AF) in Ca–Ti treated steel was systematically investigated after Mg and La addition. The inclusions in the molten steel were Ca–Al–O, Ca–Al–Mg–O, and La–Mg–Ca–Al–O after Ca, Mg, and La addition, respectively. The type of oxide inclusion in the final quenched samples was the same as that in the molten steel. However, unlike those in molten steel, the inclusions were Ca–Al–Ti–O + MnS, Ca–Mg–Al–Ti–O + MnS, and La–Ca–Mg–Al–Ti–O + MnS in Mg-free, Mg-containing, and La-containing samples, respectively. The inclusions distributed dispersedly in the La-containing sample. In addition, the average size of the inclusions in the La-containing sample was the smallest, while the number density of inclusions was the highest. The size of effective inclusions (nucleus of AF formation) was mainly in the range of 1–3 μm. In addition, the content of ferrite side plates (FSP) decreased, while the percentage of AF increased by 16.2% due to the increase in the number of effective inclusions in the La-containing sample in this study.     

摩擦焊接碳钢（EN24）和镍基高温合金（IN718）的显微组织和力学性能

Continuous-drive rotary friction welding was performed to join cylindrical specimens of carbon steel (EN24) and nickel-based superalloy (IN718), and the microstructures of three distinct weld zones—the weld interface (WI)/thermo-mechanically affected zone (TMAZ), the heat-affected zone (HAZ), and the base metal—were examined. The joint was observed to be free of defects but featured uneven flash formation. Electron backscatter diffraction (EBSD) analysis showed substantial changes in high-angle grain boundaries, low-angle grain boundaries, and twin boundaries in the TMAZ and HAZ. Moreover, significant refinement in grain size (2–5 μm) was observed at the WI/TMAZ with reference to the base metal. The possible causes of these are discussed. The microhardness profile across the welded joint shows variation in hardness. The changes in hardness are ascribed to grain refinement, phase transformation, and the dissolution of strengthening precipitates. The tensile test results reveal that a joint efficiency of 100% can be achieved using this method.     

汽车暴露面板带有表面条状缺陷的夹杂物分布特征分析:一种定量电解方法

The specific distribution characteristics of inclusions along with the sliver defect were analyzed in detail to explain the formation mechanism of the sliver defect on the automobile exposed panel surface. A quantitative electrolysis method was used to compare and evaluate the three-dimensional morphology, size, composition, quantity, and distribution of inclusions in the defect and non-defect zone of automobile exposed panel. The Al₂O₃ inclusions were observed to be aggregated or chain-like shape along with the sliver defect of about 3–10 μm. The aggregation sections of the Al₂O₃ inclusions are distributed discretely along the rolling direction, with a spacing of 3–7 mm, a length of 6–7 mm, and a width of about 3 mm. The inclusion area part is 0.04%–0.16% with an average value of 0.08%, the inclusion number density is 40 mm?2 and the inclusion average spacing is 25.13 μm. The inclusion spacing is approximately 40–160 μm, with an average value of 68.76 μm in chain-like inclusion parts. The average area fraction and number density of inclusions in the non-defect region were reduced to about 0.002% and 1–2 mm?2, respectively, with the inclusion spacing of 400 μm and the size of Al₂O₃ being 1–3 μm.     

在酸性溶液中加压氧化三价砷离子和二价铁离子

The co-oxidation of As(III) and Fe(II) in acidic solutions by pressured oxygen was studied under an oxygen pressure between 0.5 and 2.0 MPa at a temperature of 150°C. It was confirmed that without Fe(II) ions, As(III) ions in the solutions are virtually non-oxidizable by pressured oxygen even at a temperature as high as 200°C and an oxygen pressure up to 2.0 MPa. Fe(II) ions in the solutions did have a catalysis effect on the oxidation of As(III), possibly attributable to the production of such strong oxidants as hydroxyl free radicals (OH·) and Fe(IV) in the oxidation process of Fe(II). The effects of such factors as the initial molar ratio of Fe(II)/As(III), initial pH value of the solution, oxygen pressure, and the addition of radical scavengers on the oxidation efficiencies of As(III) and Fe(II) were studied. It was found that the oxidation of As(III) was limited in the co-oxidation process due to the accumulation of the As(III) oxidation product, As(V), in the solutions.     

人工闪锌矿氧压酸浸过程中Cu2+的催化机理研究

The potential autoclave was used to study the catalytic mechanism of Cu2+ during the oxygen pressure leaching process of artificial sphalerite. By studying the potential change of the system at different temperatures and the SEM–EDS difference of the leaching residues, it was found that in the temperature range of 363–423 K, the internal Cu2+ formed a CuS deposit on the surface of sphalerite, which hindered the leaching reaction, resulting in a zinc leaching rate of only 51.04%. When the temperature exceeds 463 K, the system potential increases steadily. The increase in temperature leads to the dissolution of the CuS, which is beneficial to the circulation catalysis of Cu2+. At this time, the leaching rate of Zn exceeds 95%. In addition, the leaching kinetics equations at 363–423 and 423–483 K were established. The activation energy of zinc leaching at 363–423 and 423–483 K is 38.66 and 36.25 kJ/mol, respectively, and the leaching process is controlled by surface chemical reactions.     

超声振动辅助钨极惰性气体焊接异种金属 316L 和 L415

Ultrasonic vibration assisted tungsten inert gas welding was applied to joining stainless steel 316L and low alloy high strength steel L415. The effect of ultrasonic vibration on the microstructure and mechanical properties of a dissimilar metal welded joint of 316L and L415 was systematically investigated. The microstructures of both heat affected zones of L415 and weld metal were substantially refined, and the clusters of δ ferrite in traditional tungsten inert gas (TIG) weld were changed to a dispersive distribution via the ultrasonic vibration. The ultrasonic vibration promoted the uniform distribution of elements and decreased the micro-segregation tendency in the weld. With the application of ultrasonic vibration, the average tensile strength and elongation of the joint was improved from 613 to 650 MPa and from 16.15% to 31.54%, respectively. The content of Σ3 grain boundaries around the fusion line zone is higher and the distribution is more uniform in the ultrasonic vibration assisted welded joint compared with the traditional one, indicating an excellent weld metal crack resistance.     

活化天然矿石选择性还原二氧化碳为无定形碳

Natural magnetite formed by the isomorphism substitutions of transition metals, including Fe, Ti, Co, etc., was activated by mechanical grinding followed by H₂ reduction. The temperature-programmed reduction of hydrogen (H₂-TPR) and temperature-programmed surface reaction of carbon dioxide (CO₂-TPSR) were carried out to investigate the processes of oxygen loss and CO₂ reduction. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDS). The results showed that the stability of spinel phases and oxygen-deficient degree significantly increased after natural magnetite was mechanically milled and reduced in H₂ atmosphere. Meanwhile, the activity and selectivity of CO₂ reduction into carbon were enhanced. The deposited carbon on the activated natural magnetite was confirmed as amorphous. The amount of carbon after CO₂ reduction at 300°C for 90 min over the activated natural magnetite was 2.87wt% higher than that over the natural magnetite.     

企业Intranet网络建设探析

企业Intranet网络建设发展迅速,但建设过程中企业往往缺乏科学的总体规划.本文对建设企业Intranet网络提出了有参考价值的建设思路,供企业领导和技术人员参考.     

具有智能端子的通用型数据采集系统

提出一种小型通用型数据采集系统的结构，输入端子可接任何形式的信号，如模拟量、开关量和脉冲量，输出信号采用分时传送方式输出，适用于各种生产过程的参量采集。     

甲醇生产过程的模拟和优化PC脱碳过程的模拟和简化模型(Ⅰ)

对甲醇生产PC脱碳过程进行了模拟,研究了吸收塔出口气体CO2和CH4浓度随吸收塔入口气体压力之间的变化;吸收塔出塔气体浓度随入塔流量之间的变化;油田气组成变动时吸收塔出入口之间的组成关系;出塔组成与气液比之间的关系;压缩功以及建立了吸收子系统的简化模型;并获得了相应的结论.     

强反应电解质形成的移动化学反应界面：实验分析

将移动化学反应界面的实验（引自Ｊ．Ｐｈｙｓ．Ｃｈｅｍ．１９７０，７４：１１２２．Ａｎａｌ Ｃｈｅｍ１９０；４２：３２１和Ｊ．Ｃｈｒｏｍａｔｏｇｒ．１９９３，６８３：１７９）与移动化学反应界面理论的预测作了对比性研究。结果表明：实验结果与理论的预测吻合．因此，实验验证了理论的有效性。     

柳枝中药用成分的研究

采用溶剂萃取和层析的方法，从柳枝中分离得到一组酚类葡萄糖苷，其中包括水杨苷等．气相色谱分析结果显示，样品中酚类葡萄糖苷的含量在45%～55%之间，实验表明，丙酮的萃取效果优于乙醇．     

智能复合材料的增韧机理与能量释放率

基于细观力学方法分析了智能复合材料中的微裂纹与夹杂的相互作用，导出了裂纹扩展的能量释放率，分析了形状记忆合金的多机理联合增韧作用．研究表明，智能复合材料具有相变和异性夹杂的双重增韧机理，而且其韧度可由外部条件控制，因而有可能使这种复合材料展示出超级力学性能     

大鼠染色体的非组蛋白、核糖核蛋白(RNP)与银染蛋白三者关系的研究

本文应用ＴＥＭ技术、电镜细胞化学、胶体金标记和银染技术结合研究了大鼠骨髓细胞染色体现有架。超薄切片结合ＲＮＰ优先染色法在染色体原位显示ＲＮＰ，同时又结合银染电镜扭亏为盈主ＲＮａｓｅ－胶体金定位显示ＲＮＡ，结果显示金颗粒与银颗粒在染色体中分布的位置与ＲＮＰ所在部位恰好一致。说明ＲＮＰ中的蛋白质含有角染的酸性蛋白，即所观察到的染色体骨架非组蛋白、ＲＮＰ中的蛋白部分，银染蛋白三者是一致的。     

ApSimon的造币厂问题

给出了在艾波西蒙造币厂问题上若干新的研究成果：（１）给出了ｎ＝６,７时的更好的上界：ｍｉｎ（Ｐ６）≤３２,ｍｉｎ（ｐ７）≤６４,当ｎ＝６时,ａｉ,ｂｉ依次取为（８,６,６,０,４,１）,（０,３,６,５,５,２）,当ｎ＝７时,ａｉ,ｂｉ依次取为（１１,１１,１０,３,８,８,０）,（０,２,２,９,９,８,６）．（２）给出了一种解决艾波西蒙问题的计算机搜索算法,对于给定的ｎ,按此算法可找出较好的ｐｎ．     

用VB制作“肽链的延长及终止阶段”CAI课件

运用计算机多媒体CAI课件进行课堂辅助教学,是提高教学质量的一种重要手段,本介绍了用VB制作《生物化学》课中“肽链的延长及终止阶段”CAI课件的方法及其应用,并指出CAI课件在教学过程中主要起教学辅助作用。     

由Co^2＋和OH^—形成的移动化学反应界面实验的报道

进行了由Ｃｏ＾２＋和ＯＨ＾－形成的“移动化学反应界面”的实验。实验中，观察了界面移动速度（μｔｈｅ＾αβ）对比。通过改变Ｃｏ＾２＋和ＯＨ＾－的浓度和反应管中电场强度等参数，总共完成了２６次实验。统计分析表明：μｏｂｓ＾αβ和μｔｈｅ＾αβ的相关系数是０．９９７，μｔｈｅ＾αβ和μｏｂｓ＾αβ之间的线性回归方程是μｔｈｅ＾αβ＝１．０４４μｏｂｓ＾αβ＋０．１３６。结果显示：实验观察的界面移动速度（