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.     

回归与奉献——兼论俄狄浦斯王的心理受挫与渴望

因犯了杀父娶母大罪而被迫弄瞎双眼流放而死以解除百姓于灾难之中的俄狄浦斯王,一直作为一个罪人而承受了因果报应式惩罚。但是,随着现代心理学理论在文学批评理论领域的应用,人们才有可能从他受挫的心理出发去研究这一情节的必然性,并因此而对他的人品重新作出评价。在他的三次冒险中,始终贯穿着他强烈追求母爱的潜意识渴望,贯穿着他对人民的兴旺与幸福的无私奉献。因此,他暂时脱离母爱而流放致死只不过是一个楔子——把剧情推向高潮以更加充分地歌颂他的光辉和伟大。     

余光中散文词语赏析

余光中的散文是作者学识、智慧、才情、文采的自然流露。余光中把汉语中相对稳固的词语大胆地加以剖析、重组,用他那非同一般的妙言趣语,描绘出一种美轮美奂的景致,以其超拔的才情和独特的幽默显示了自身卓越的文化品位。     

从诗歌文本看戴望舒心路历程

戴望舒的诗作以典型的个人话语书写内心情感历程.少数关注现实的诗作并未影响他前期的基本取向;他咏叹情爱,但更多遭遇苦恋,未曾获得幸福;他咏写对精神家园的追寻,逼仄的现实前却无由逃遁;抗战中的罹难,最终转变了诗人的心路走向,诗人由此实现对现实的复归,并完成了其不朽之杰作.     

童年,海明威心头永远的痛

男扮女装的童年经历导致了海明威终身的痛苦.它对他人格的形成至少具有精神分析学方面的三种意义:第一,导致他对女性既依赖又忽略的双向情感以及对名誉地位的终身焦虑;第二,导致了他强迫性的竞争意识及较强的攻击性;第三,导致了他的自卑以及由此而产生的自我憎恨.     

预言的深刻--兼论鲁迅的怀疑精神

与同时代的思想家比较，鲁迅的思想具有超越时空的穿透性，显现出预言般的深邃。他对民主与科学的质疑，对革命及革命者的怀疑，对革命胜利后的预测，对自己死后被利用的猜测，都已经程度不同地被史实所印证。这得力于鲁迅彻底的怀疑精神，使他能够以“于浩歌狂热之际中寒；于天上看见深渊”的独特视角，去审视人类自身及其社会环境，对过去、现在、未来作出正确的判断和准确的预测。     

晚唐诗人李贺的生死观——兼论唐代诗人对生与死的理解与诠释

诗人李贺在短暂的生命旅途中,病痛和政途失意造成心理的阴霾在其诗歌中有多方面的表现。诗风的急剧转变也是畏惧死亡的某种心理折射;生命意义的追寻与构建,在美好的仙境中寄托超脱凡世的追求,体现了李贺自我超越的生命态度。儒家中庸生死观在唐人思想中有表现,唐朝诗人追求精神超越,说明李贺也不是独立存在的个体。品读李贺的诗歌,既能深刻地体悟到李贺本人的生死观,又能进而理解唐人对生死的各种诠释。     

博尔赫斯的图书馆情结

博尔赫斯一生与书籍和图书馆结下了不解之缘,主要源于小时候父母亲和家庭藏书的影响,以及他对书籍的钟情,对文学创作的热爱,对图书馆职业的选择和毕生从事图书馆工作。《通天塔图书馆》梦幻般的描述,集中体现了他的图书馆情结。     

舒曼艺术歌曲的音乐特色

本文主要从音乐风格、歌曲构建特点和情感表现等方面分析了舒曼艺术歌曲的音乐特色。指出其艺术歌曲的主要音乐特色表现为:借助于诗歌的明确语义,充满浪漫主义的音乐风格;歌曲旋律与钢琴伴奏结合完美,音乐形象鲜明;情感丰富,重视音乐与生活的联系。并通过其作品,透视出舒曼热情真挚的性格思想和充满浪漫主义色彩的音乐人生。     

个人与社会关系的互动性--对<论个人在历史上的作用>的思考

我们以前只看到社会关系对人的决定性,片面强调人是社会关系的产物,忽视人的主体创造性.事实上,人与社会关系具有互动性,社会关系的存在制约着人的活动及其才能的发挥;人的实践活动又在不断改变着社会关系的状况.社会关系的改变和人的自我改变的一致只能在人的实践活动中才能得到合理的理解.     

抗争:解读海明威的另一主题

文学评论一直把海明威小说创作的主题归结为勇气和死亡,这一归结使得海明威的小说创作显得单薄、苍白,不足以说明海明威对世界文学所作的贡献。通过对海明威作品的整体分析,可把海明威一生的创作主题归结为抗争。如此不仅能统摄海明威所有的作品,而且其主人翁的“硬汉”形象也清晰地显现出一条由单薄到丰富、而至完满的脉络,从而丰富了海明威创作的内涵。从人与自然的抗争、人与人的抗争、与自身的抗争三个方面进行了阐述。