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.     

采用超声组装与滚压工艺制备铝–碳纳米管复合材料

This study introduced a novel fabrication of aluminum–carbon nanotube (CNT) composites by employing bulk acoustic waves and accumulative roll bonding (ARB). In this method, CNT particles were aligned using ultrasonic standing wave in an aqueous media, and the arrayed particles were precipitated on the aluminum plate substrate. Then, the plates rolled on each other through the ARB process with four passes. Optical and scanning electron micrographs demonstrated the effective aligning of CNTs on the aluminum substrate with a negligible deviation of arrayed CNTs through the ARB process. The X-ray diffraction pattern of the developed composites showed no peaks for carbon and aluminum carbide. In addition, tensile tests showed that the longitudinal strength of the specimens processed with aligned CNTs was significantly greater than that of the specimens with common randomly dispersed particles. The proposed technique is beneficial for the fabrication of Al–CNT composites with directional mechanical strength.     

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.     

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.     

网页设计中的视觉构成分析

网页设计是一门新兴的设计类和网络的交叉学科.它作为现代艺术设计中的综合门类,其艺术表现形式远远超出了平面设计的概念,因此,既要把设计艺术中的平面构成因素整合到网页设计艺术中,又要集艺术创作与多媒体技术于一体.本文通过对网页设计中版面的构成要素和文字、图片、颜色的视觉构成进行分析,结合人们在浏览信息时的视觉习惯,探讨了网页视觉信息如何更有效、更为合理地表现与传达.     

从风景写生走向设计--艺术设计专业风景写生教学改革思考

学生设计思维的培养应该是循序渐进的过程,设计专业的风景写生训练在教学观念、方法及手段等方面都要突出设计的内涵,注重设计意识的训练,使客观状态下的自然景观具有设计意味,从而为学生走向设计领域打好基础。     

构建工科学生“实践-科研-企业”平台

认为基础的专业实验能够培养学生的动手能力,设计性实验能够培养学生的动脑能力。设计性实验重点在培养学生设计实验的能力和数据处理及模拟分析方面。应该根据学生的能力和特点采取灵活有效的方式。     

用MATLAB语言开发CACSD应用软件的一种方法

本文采用目前较流行的ＭＡＴＬＡＢ语言,开发出一个基于典型单闭环及串级控制系统的计算机辅助设计与仿真分析的Ｗｉｎｄｏｗｓ应用软件,本软件充分利用ＭＡＴＬＡＢ语言提供的Ｗｉｎｄｏｗｓ图形用户界面设计及其仿真工具ＳＩＭＵＬＩＮＫ的强大功能。     

艺术设计的创新教育研究

随着市场经济不断发展，竞争日趋激烈，对艺术设计人才的综合素质提出了全新的要求。在当前形势下，全面推进素质教育，培养高素质的创新人才是高校艺术设计教育的重要使命。艺术设计教育应该在注重历史文化传承和实际应用的同时，特别注重设计意识和创新能力的培养，将科掌人文知识作为艺术设计教育中的重要组成部分，立足当代教育与设计实践，建构科掌可行的我国艺术设计教育体系以及与之相适应的艺术设计人才培养机制。     

CI战略中的服装设计师

服装企业Cl品牌战略是个系统工程,服装设计师在这个系统工程中的地位和作用应该正确确定。结合国内外服装业实际情况,对当前国内服装业不重视设计和设计师的情况提出一些看法,认为某些服装企业急功近利的做法时企业本身和中国的服装设计事业都是有害的,如不形成科学的客观的认识,将后患无穷。本文提出的设计文化概念是服装企业品牌战略的重要环节,指出:对服装设计师设计声誉的作用视而不见或剥夺抵制,是毫无远见的、落后的非理智行为——尽管这种行为普遍存在于中国的服装企业中。因此,尽快认识服装Cl战略中的设计文化,认识设计文化中的服装设计师,对一个具有现代企业概念的真正的服装企业家来说是至关重要的,并且对企业制定和落实Cl战略具有积极的现实意义和指导意义。     

单片机应用系统的可靠性设计

可靠性设计是单片机应用系统设计必不可少的设计内容。本文从现代电子系统的可靠性出发,详细论述了单片机应用系统的可靠性特点,提出了芯片选择、电源设计、PCB制作、噪声失敏控制、程序失控回复等集合硬件系统的可靠性设计技术和软件系统的可靠性设计技术的解决方法,可供单片机应用系统的开发人员借鉴与参考。     

设计价值论

设计价值是体现在设计成果里的社会劳动，其构成元素的个性化特征具体表现为有形价值和无形价值。评价设计的好坏程度，有效地提高设计水平，都完全基于设计价值表现的五大基点：基本构成、创造性、表现性、适时性、时代性。面对设计的发展，已不是限于设计表象而评价设计，全面、深刻地理解和把握这五个大基点，能从设计价值的构成本质上正确把握设计内涵和提升设计水平，这是今后发展的首要问题。     

J2EE平台WebGIS设计技术探讨

针对传统WebGIs设计方法的局限性，利用Java平台无关性的优点，为拓展GIS在电子政务中的应用，提出了基于J2EE平台的Browser／server模式的分布式解决方案，并以一个城市电子地图为例，着重探讨了J2EE平台上采用中间件（MapXtrerne）设计和架构应用于电子政务的WebGIS的思想，主要包括客户端的选择、功能考虑以及服务器端的结构设计等，并据此提供了一个原型．该原型的建立及其设计的思想方法对于其他更为复杂的WebGIS的开发具有借鉴意义．     

医院管理系统

介绍了利用POWER BUILDER7.0开发的一套医院管理系统，给出了该系统的先进的管理功能以及该系统的设计思想和特点，同时说明了设计该系统的技术背景。