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.     

山地垂直自然带的土地结构与演替理论

土地结构与演替是经过对土地类型的深入研究后提出的重要理论问题之一．本文以陕西秦巴山区为例，运用遥感技术、数理分析和计算机新技术，通过由ＧＩＳ支持的土地结构系统动力学仿真模拟与模型建立，在土地分类的基础上，从山地自然地理特点出发，对秦岭南、北坡和大巴山北坡的不同垂直带层的土地结构格局与演替模式做了理论研究．认为土地结构是土地所有属性的结合形式、联系方式与对比关系，他包括空间和功能有序两个方面；土地演替是土地结构与功能的自组织，这种自组织过程靠一定的地理过程来维持，是土地内部物流与能流转化迁移的结果，土地演替分为自然演替和人为演替两种过程．从而拓宽和纵深了土地研究的内容     

秦巴山区黑木耳害虫食丝谷蛾的生物学研究及药物防治试验

记述了秦巴山区黑木耳的重要害虫食丝谷蛾的危害、形态特征、生活史、习性及发生规律,并采用多种给药方式测定了不同杀虫剂的杀虫效果。在此基础上提出了切实可行的防治措施。     

陕西省红豆杉资源保护利用现状及对策

陕西省分布的红豆杉包括中国红豆杉(Taxsus.wallichiana Var.chinesis)和南方红豆杉(T.wallichiana Var.mairei)两种,主要分布在秦岭、巴山和关山林区,资源量约有4 500万株,生物量3.8万t.1992年,紫杉醇作为治癌药物上市以后,陕西省红豆杉种植和紫杉醇加工产业发展迅速,全省共有种植企业8家,种植红豆杉514.6 hm2,1 400万株,紫杉醇加工企业8家年加工紫杉醇精品能力170 kg.医药市场对紫杉醇需求的增长,在推动红豆杉人工种植和加工产业发展的同时,给红豆杉资源及其保护带来威胁.必须完善相关法律制度,严格红豆杉采集、培植、经营加工、运输等环节管理,有效保护野生资源.同时要制定产业扶持政策,重点支持红豆杉培植基地发展,逐步实现利用野生资源到利用人工资源的转变.     

防治西洋参立枯病木霉菌株的筛选鉴定及其小区防治效果

摘要：利用平板对峙实验及小区试验,筛选高效防治西洋参立枯病的木霉菌株,并采用ITS（internal transcribed spacer)序列分析与形态学特征相结合的方法进行种类鉴定。结果表明,供试木霉菌株在PDA平板上对立枯丝核菌(R. solani)均有抑制作用,菌株HB20111效果最好,抑制率达99.33%;菌株HB20111对西洋参立枯病的小区效果显著,与其他处理间存在显著性差异(P<0.05);第1年拌种处理对西洋参立枯病的防治效果、单株参增重率及总参增重率分别达71.81%、33.54%和92.75%;第2年蘸根处理对西洋参立枯病的防治效果、单株参增重率及总参增重率分别达91.04%、158.06%和1 369.34%;菌株HB20111的分生孢子梗为典型的单侧分枝,其他形态学特征同深绿木霉(T. atroviride)一致,ITS序列与T. atroviride同源性达100.0%,将菌株HB20111鉴定为T. atroviride。HB20111生长速度快,产孢能力强,生防效果高,有望替代化学杀菌剂应用于西洋参种植中。     

西洋参悬浮细胞培养条件的研究

通过试验论述了不同愈伤组织年龄和接种量对细胞悬浮培养的影响，从而得出最佳接种年龄及其最佳接种量；分析了培养方式和转达对细胞悬浮培养影响的原因，确定了有利于细胞生长的培养方式及转速；阐述了在美国ＶｉｒＴｉｓ公司生产的ＯＭＮＩ－ＣＵＬＴＵＲＥＢＥＮＣＨ－ＴＯＰ－２Ｌ发酵罐中，进行西洋参细胞发酵培养的结果。描述了西洋参细胞在发酵罐中的生长曲线、培养液中Ｄｏ变化曲线和培养过程中ｐＨ的变化曲线，为西洋参细胞发酵培养条件最佳化的研究提供了有关数据。     

2种新型叶面处理剂对西洋参生长的影响

以3 a生西洋参为试验材料,清水(CK1)和磷酸二氢钾(CK2)为对照,采用盆栽控制试验研究全营养酵素(T1)和澳西(T2)叶面处理剂对西洋参生长的影响.结果表明:喷施2种新型叶面处理剂对西洋参生长均有一定的促进作用.其中,T1对提高西洋参叶长、叶面积、叶绿素含量及POD,SOD酶活性的效果明显优于T2;CK2对提高叶片中可溶性糖含量的效果显著;T2明显提高了西洋参叶片中可溶性蛋白质含量.综合分析可知:在本次试验条件下,全营养酵素可作为西洋参盆栽的首选叶面处理剂.     

西洋参悬浮细胞的超低温保存研究

对西洋参悬浮细胞的超低温保存进行了初步的研究,结果表明,首先将西洋参悬浮细胞在含8％蔗糖昀西洋参液体培养基中预培养2天,然后经过10％DMSO＋8％萄葡糖的冷冻保护剂处理,以4℃（60min）、0℃（30min）、-20℃（2h）、-70℃（30min）的降温程序处理,最后投入液氯中,西洋参悬浮细胞可以生长为愈伤组织,且愈伤细织长势旺盛。     

西洋参细胞培养的研究进展

利用西洋参悬浮细胞培养技术生产人参皂甙,在理论和生产上,都具有重要意义.概述了国内外在西洋参愈伤组织培养、细胞悬浮培养和发酵培养方面的研究进展情况.     

巴山市望王山南坡边坡稳定性分析与评价

通过对巴山市望王山南坡的滑坡稳定性计算,得出了滑坡治理的主要控制参数,提出了滑坡防治方案。同时,通过节理玫瑰图、边坡稳定性分析的赤平投影图进行边坡稳定分析,提出边坡防治措施。     

山里与山外——《等他》简论

《等他》是新世纪巴山作家群的新锐作家周嘉新近出版的长篇小说.从小说题目"等他"的语言分析入手,揭示出这一语言所具有的象征性意义;在和山里与山外的比较中,指出两种文化的差异,从而使小说具有深刻的批判价值.