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.     

具有良好可再生性的新型二氧化硅磁性氧化石墨烯纳米复合材料

Graphene oxide (GO) wrapped Fe₃O₄ nanoparticles (NPs) were prepared by coating the Fe₃O₄ NPs with a SiO₂ layer, and then modifying by amino groups, which interact with the GO nanosheets to form covalent bonding. The SiO₂ coating layer plays a key role in integrating the magnetic nanoparticles with the GO nanosheets. The effect of the amount of SiO₂ on the morphology, structure, adsorption, and regenerability of the composites was studied in detail. An appropriate SiO₂ layer can effectively induce the GO nanosheets to completely wrap the Fe₃O₄ NPs, forming a core-shell Fe₃O₄@SiO₂@GO composite where Fe₃O₄@SiO₂ NPs are firmly encapsulated by GO nanosheets. The optimized Fe₃O₄@SiO₂@GO sample exhibits a high saturated adsorption capacity of 253 mg·g?1 Pb(II) cations from wastewater, and the adsorption process is well fitted by Langmuir adsorption model. Notably, the composite displays excellent regeneration, maintaining a ~90% adsorption capacity for five cycles, while other samples decrease their adsorption capacity rapidly. This work provides a theoretical guidance to improve the regeneration of the GO-based adsorbents.     

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.     

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.     

含钛高炉炉渣微波合成碳化钛及其介电性能测定

The preparation of functional material titanium carbide by the carbothermal reduction of Ti-bearing blast furnace slag with microwave heating is an effective method for valuable metals recovery; it can alleviate the environmental pressure caused by slag stocking. The dynamic dielectric parameters of Ti-bearing blast furnace slag/pulverized coal mixture under high-temperature heating are measured by the cylindrical resonant cavity perturbation method. Combining the transient dipole and large π bond delocalization polarization phenomena, the interaction mechanism of the microwave macroscopic non-thermal effect on the titanium carbide synthesis reaction was revealed. The material thickness range during microwave heating was optimized by the joint analysis of penetration depth and reflection loss, which is of great significance to the design of the microwave reactor for the carbothermal reduction of Ti-bearing blast furnace slag.     

“质明”正解

"质明"的"质"训为"端始","质明"训为"黎明的开始"的观点不甚允当。"质"应当训为正,"质明"就是天正亮。"质明"不是"黎明的开始",而恰恰是黎明的"结束"。     

词义札记二则

前贤对古文的注释多有商榷之处。本文围绕古文“更取器用”之“更”和“众不见信”之“众”、“见”的训释进行讨论和辨析,提出释“更”为“取”,“众”不作“终”训,“见”当属指代用法．     

腾冲“罗古城”、“罗密城”的历史渊源及其语义考证

腾冲的“罗古城”、“罗密城”是白族的先民在宋“大理国”时期所建。它们以白语命名,“罗古城”是“虎踞的关口之城”,“罗密城”是“老虎的生命之城”。它们不是后人传说的“哥哥”城、“妹妹”城的意思。     

非匀强电场对颗粒污垢的抑垢特性

目前,电场抑垢研究兴趣集中于电场对碳酸钙晶体形貌的改变,电场对已成垢的颗粒是否有抑垢作用鲜有研究。针对电场颗粒污垢抑垢机理不明的问题,提出非匀强电场颗粒物污垢抑垢模型,解释了电场对流体管道内污垢颗粒存在抑垢作用。电场60V至180V、频率50Hz、颗粒质量100条件下研究结果表明:匀强电场并不会使颗粒产生抑垢作用,颗粒污垢在非匀强电场受到介电泳力（）,改变原本运动轨迹,达到抑垢的效果。随着电场强度升高,碳酸钙颗粒受到的从,升至。硫酸钙受到的从升至。碳酸镁颗粒受到的升至。电场强度对多种污垢颗粒产生的,是影响抑垢效果的关键因素。     

"象"的境界与"数"的真理--作为中西古典美学意义之发端的老子"象论" 与毕达哥拉斯学派的"数论"

老子“象论”与毕达哥拉斯学派“数论”分别构成了中西古典美学的意义之发端。两在思想路向上存在着巨大的差异。老子“象论”及其人生论的思想路向启发了中国古典美学中的“意象”本体论和以“境界”为最高审美理想的思想;毕达哥拉斯学派“数论”及其知识论的思想路向启发了西方古典美学中的“形式”本体论和以“真理”为最高审美理想的思想。     

《论语》"当仁"章释义考辨

考《论语》“当仁,不让于师”一章注释,或以“谦让”释“让”,以“老师”“先生”释“师”,或以“谦让”释“让”,以“众”释“师”。笔者认为二说俱有偏误,从语言文字、孔子思想、社会实情三点辨正。     

日本优质粳稻引种试验研究初报

对17个日本优质粳稻品种进行试种表明,各品种在本地气候条件下均能正常结实。生长期最长175天,最短仅为143天。其中以“快出”、“秋”两品种综合性状表现最好,其次是“一见钟情”、“中生新千本”、“笹锦”、“日本晴”、“广光”、“越光”、“法令”、“明星”、“山彦”和“小金胜”。“秋田小町”、“日光”等5个品种表现较差。     

<诗经>释义四题

结合语词产生的环境和具体运用情况,对“雨雪”、“窈窕”、“采采”、“愿言”、“薄言”等词语的意义作出较合理的解释。     

清代两位诗话家对诗趣的集中论评与阐说

清代袁枚、朱庭珍对诗趣予以了集中论评与阐说。袁枚评诗推尚偏于由才性而催生出的"趣"的审美形态,他以"趣"为审美标的,以性灵为根本,以天才、真、自然为支点,建构出一个有别于他人的诗趣论系统。朱庭珍评诗反对"恶趣"、"魔趣",推尚意趣充蕴之作;他强调作诗要"培之以理趣之府",提出了"意趣活泼"的审美要求,在诗趣的生成创造上,则论及到由"情"而"趣"、由"思"而"趣",对诗中之趣语的运用也予以了界划。他们为古典诗趣论的最终深化和完善做出了突出的贡献。     

“玉山雅集”与“北郭诗社”的差异性研究

"玉山雅集"与"北郭诗社",以张士诚入吴为标志,先后繁荣于吴中地区。同为吴中文人团体,二者有巨大的差异,表现在三个层面:在雅集方式上,呈现出从"娱乐化"向"文艺化"的转变;在文人心态上,表现为从"纵欲"到"闲适"、从"庆幸"到"无奈"的转变;在诗学思想上,诗人对诗歌功能的理解、诗法与诗体的选择及诗歌的审美风貌都不同。这三个层面相辅相成,既体现了易代之际吴中文人内部的差异性,也反映了吴中文人的整体风貌。