Novel blast furnace operation process involving charging with low-titanium vanadium–titanium magnetite carbon composite hot briquette

An innovative process of blast furnace (BF) operation involving charging with low-titanium vanadium–titanium magnetite carbon composite hot briquette (LVTM-CCB) was proposed for utilizing LVTM and conserving energy. In this study, the effect of LVTM-CCB charging ratio on the softening, melting, and dripping behaviors of the mixed burden was explored systemically, and the migration of valuable elements V and Cr was extensively investigated. The results show that with increasing LVTM-CCB charging ratio, the softening interval T₄₀-T₄ increases from 146.1℃ to 266.1℃, and the melting interval T_D-T_S first decreases from 137.2℃ to 129.5℃ and then increases from 129.5℃ to 133.2℃. Moreover, the cohesive zone becomes narrower and then wider, and its location shifts slightly downward. In addition, the recovery ratios of V and Cr in dripped iron first increase and then decrease, reaching maximum values of 14.552% and 28.163%, respectively, when the charging ratio is 25%. A proper LVTM-CCB charging ratio would improve the softening–melting behavior of the mixed burden; however, Ti(C,N) would be generated rapidly in slag when the charging ratio exceeds 25%, which is not favorable for BF operation. When considering the comprehensive softening–melting behavior of the mixed burden and the recovery ratios of V and Cr, the recommended LVTM-CCB charging ratio is 20%.     

A susceptibility locus for lung cancer maps to nicotinic acetylcholine receptor subunit genes on 15q25

Lung cancer is the most common cause of cancer death worldwide, with over one million cases annually. To identify genetic factors that modify disease risk, we conducted a genome-wide association study by analysing 317,139 single-nucleotide polymorphisms in 1,989 lung cancer cases and 2,625 controls from six central European countries. We identified a locus in chromosome region 15q25 that was strongly associated with lung cancer (P = 9 x 10(-10)). This locus was replicated in five separate lung cancer studies comprising an additional 2,513 lung cancer cases and 4,752 controls (P = 5 x 10(-20) overall), and it was found to account for 14% (attributable risk) of lung cancer cases. Statistically similar risks were observed irrespective of smoking status or propensity to smoke tobacco. The association region contains several genes, including three that encode nicotinic acetylcholine receptor subunits (CHRNA5, CHRNA3 and CHRNB4). Such subunits are expressed in neurons and other tissues, in particular alveolar epithelial cells, pulmonary neuroendocrine cells and lung cancer cell lines, and they bind to N'-nitrosonornicotine and potential lung carcinogens. A non-synonymous variant of CHRNA5 that induces an amino acid substitution (D398N) at a highly conserved site in the second intracellular loop of the protein is among the markers with the strongest disease associations. Our results provide compelling evidence of a locus at 15q25 predisposing to lung cancer, and reinforce interest in nicotinic acetylcholine receptors as potential disease candidates and chemopreventative targets.     

高潮滩盐沼前缘沉积物—水界面NH_4~+-N浓度的潮周期变化

基于高精度测量仪器Vectrino小威龙点式流速仪,对崇明东滩高潮滩盐沼前缘进行为期7d的连续观测和采样.采用纳氏试剂光度法对样品进行分析,分析结果表明:NH4+-N浓度分布在0～1.1652 mg·L-1,平均为0.3830 mg·L-1;涨潮时潮滩沉积物成为NH4+-N的源,落潮时潮滩沉积物表现为NH4+-N的汇;沉积物一水界面NH4+-N垂直分布存在复杂的变化特征;近底层10cm处潮汐流速对NH4+-N浓度的影响机制十分复杂.     

多变量离散系统的鲁棒自适应极点配置算法

对带有外部扰动和未建模动态的多变量系统提出了一种自适应极点配置算法．证明了当外部扰动的上界和未建模动态的相对界满足一定约束时,只要将闭环极点配置到原点的适当小邻域内,得到的闭环自适应控制系统具有鲁棒稳定性．     

不同食料对野生蚕蛹营养成份的影响

随机选取采食七种树叶的野生蚕蛹,分别测定粗蛋白,脂肪和氨基酸,结果发现:蚕蛹的粗蛋白、脂肪,十七种氨基酸随采食的树叶不同其含量也有差异,这一结果提示我们:不同食料对野生蚕蛹的蛋白质,脂肪和氨基酸的含量有明显的影响,通过不同的食料,可以改变野生蚕蛹中主要营养成份的含量。     

火炮零部件设计计算绘图一体化研究

分析了火炮ＣＡＤ发展现状,探讨了在火炮设计过程中,通过在Ｉ－ＤＥＡＳ软件上进行了二次开发,建立零部件的三维对数化模型,根据设计计算程序的输出自动实现零部件不同结构类型三维实体的输出的问题,提出了火炮零部件设计,计算,绘图一体化方案,详细介绍了方案中各组成部分的功能及实现方法,结合身管设计实例介绍了整个方案的设计思想,该方案的提出将进步一提高火炮设计的效率和质量,为实现火炮总体结构的参数化,系列化和     

基于构造的布局启发方法

布局问题属于ＮＰ完全问题已知被研究多年,关于它的求解方法多为启发式方法,本文在分析了布局问题特性的基础上,提出了一种基于构造的布局启发方法,该方法既考虑到布局总问题的不干涉的约束及又考虑了其它的布局约束,从而更加全面,准确地指导布局求解的进行,本文还首次提出了“虚容器”的概念,从而使定序函数和定位函数的计算易于进行。     

Ultrastructural localization of microfibrillar fibulin-1 and fibulin-2 during heart development indicates a switch in molecular associations

The microfibrillar proteins fibulin-1 and fibulin-2 were previously identified as prominent components of the endocardial cushion tissue (ECT) during heart development and shown to persist in adult valves and septa. Immunogold staining has now been used to compare their localization in embryonic (days 9–11) and adult mouse heart with that of fibronectin and the chondroitin sulphate proteoglycan versican. All four proteins were deposited in the ECT, which consists of a hyaluronan-rich, mainly unstructured matrix, but were barely detectable in myocardial basement membranes or within endocardial cells. Digestion with hyaluronate lyase selectively released the fibulins and versican but not fibronectin from the ECT. Yet neither of the two fibulins bound to hyluronan in solid-phase assays, in contrast to versican. In the adult heart valve, all four proteins could be detected close to cross-striated collagen fibrils or microfibrils, but only versican was lost upon exposure to hyaluronate lyase. The data indicate that fibulins are associated with the hyaluronan-matrix of ECT through a bridge of versican, but that this association changes upon valve development to another supramolecular, presumably microfibrillar organization based on fibronectin and/or fibrillins. Received 3 April 1998; accepted 8 April 1998     

ASD、VSD和MS患者SOD活力的研究

目的：检测房间隔缺损（ＡＳＤ）、室间隔缺损（ＶＳＤ）和二尖瓣狭窄（ＭＳ）的患者红细胞中ＳＯＤ活力,分析术后ＳＯＤ活力的变化。方法：应用四氮唑蓝法（ＮＢＴ法）。结果：ＡＳＤ、ＶＳＤ和ＭＳ患者红细胞中ＳＯＤ活力明显低于正常人,术后可见ＳＯＤ活力逐步提高,患者年龄愈小,ＳＯＤ活力增加幅度愈大。结论：ＡＳＤ、ＶＳＤ和ＭＳ患者术后可使ＳＯＤ活力增加,有利于保护心脏正常功能。