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.     

英汉句法差异及其转换翻译浅议

语言是思维的外壳，思维是语言的脊梁。英汉两民族思维习惯的不同，造就了英汉两种语言句法上的根本差异。这些差异具体表现为形态语和无形态语、树型结构与线型结构、形合与意合、有主句和无主句、人称主语句式与非人称主语句式以及句首重心与句尾重心之间的差异。充分认识这些差异，并在翻译过程中进行相应转换和调整，才能使译自如圆润。     

炼油企业生产经营规划决策模型

企业综合发展规划是一个综合考虑企业内、外各种影响因素,并对企业重大生产经营活动及其各种资源从时间上和空间上作出具体统筹安排的综合发展纲要,它既是企业经营战略(战略方针、战略目标和战略措施等)的具体落实,又是企业各种生产经营活动的行动纲领和基本依据。所以,科学、合理的综合规划,对企业保持长期持续稳定的发展,提高企业的总体经济效益具有重要的作用和意义。文章把系统动力学方法与线性规划方法相结合,探讨了炼油企业的规划与决策问题,建立了炼油企业生产经营规划决策模型,并设计出相应的软件,其成果进行了实际应用。     

刘禹锡对贬谪文学传统的超越

刘禹锡是中国文学史上一位重要的贬谪诗人,贬谪使刘禹锡备尝忧患磨难,但也正是贬谪激发了他借文学创作抒发郁愤并与忧患抗争的动力和勇气。他不仅以巴山楚水二十三年的时间,刷新了中国文人遭贬期限的最高记录,而且以豪迈乐观的精神创造了贬谪文学豪健雄奇、冷峻犀利的崭新风貌,打破了贬谪文学沉湎于忧怨、孤愤的套数,开辟了贬谪文学写作的新路径。从他的作品中可以领悟到一种傲视忧患、独立不移的气概和迎接苦难、超越苦难的情怀,一种坚毅高洁的人格内蕴。     

写在《实验动物管理条例》发布实施三十周年

《实验动物管理条例》（以下简称条例）是我国第一部关于实验动物管理工作的行政法规）《条例》实施30年来,在实验动物工作规范化、法制化管理,保障实验动物和动物实验的质量,推动我国科技发展和民生保障等方面发挥了重要作用。但随着科技进步、社会经济发展和立法工作的深入,实验动物科学研究和管理工作中出现了诸多新情况和新问题,《条例》在实验动物管理工作中的作用已不能完全适应科技创新、经济与社会发展的需要。因此,修订《条例》并将其上升到法律层面,对规范实验动物管理工作,保证实验动物质量,保障实验动物福利,维护公共卫生安全,支撑科技创新,以及促进国际科技合作与交流具有非常重要的意义。     

从汉英对比看对比语言学问题

世界各民族语言存在着一致性和相异性。从汉英对比可以看出，一致性表现在概念的一致性，思维的一致性和句子结构一致性等。相异性表现在化和宗教信仰、地理环境、气候不同形成不同表达方式、对句子成分不同认识导致句子结构差异、思维反应现实要素顺序不同导致词序差异、思维模式的不同导致篇章语义结构模式的不同等等。对一致性和相异性共时研究是对比语言学的根本任务。它对外语学习、外语教学和翻译有着重要的指导意义。     

整流装置故障检测与诊断报警系统的设计

本文具体论述了以PLC为控制核心的硬件系统设计,脉冲的产生、整流装置的实时监控、诊断和报警均由PLC完成,数据采集单元由电流传感器、数/模转换器、电气元件等组成。论述了实现实时监控、诊断和报警的控制系统的软件设计。     

《兰亭集序》汉译英转换中的中西文化对比

在《兰亭集序》汉译英转换过程中,中西方文化在思维方式、句式结构、语法演绎转换、文化典故运用和语言结构形式等方面,均表现出巨大差异.译者只有深入领会和理解源语和目的语在社会、历史和文化上的差异,才能实现准确巧妙的翻译转换目的.     

Authorware中数据库的开发和应用

随着社会信息容量的日益膨胀,多媒体教学软件中需要处理的数据越来越多,多媒体制作工具软件与数据库技术的结合越来越密切.详细地论述了在多媒体制作软件Authorware中数据库开发和应用的准备知识和关键步骤,并通过实例介绍了在Authorware中数据库的开发和应用的设计方法和开发过程.     

真菌和昆虫的互作关系及协同进化

真菌与昆虫是自然界存在的两个最大生物类群.两者在漫长的进化过程中逐渐形成了复杂而密切关系,无论在昆虫的体表还是昆虫的体内,都存在着丰富的真菌类群.许多昆虫都与真菌间形成了互惠的共生关系,因而才得以更好的利用资源、适应环境和占领新的生境.研究真菌和昆虫的互作和协同进化对于我们认识生物多样性的形成、物种的分化、生物地理分布等有着重要意义.