某铬矿热成型机配料站的优化设计

针对某钢厂矿热炉生产线配套工段铬矿热成型机配料站圆盘给料机故障率高,无法满足原有生产线和新建生产线使用问题,对圆盘给料机进行了技术改造,设计了一种新型螺旋状蜗壳圆盘给料机套筒。改造后的圆盘给料机,在不增加电机功率的情况下,降低了圆盘给料机故障率,满足了生产要求。     

新型圆盘给料机

新型圆盘给料机鞍山矿山机械厂研制出ＰＺＷ２０００型圆盘给料机。该产品是一种轻型、高效的物料输送设备，首次采用零度渐开线包络螺杆螺轮副传动新技术，整机原理新颖、传动效率高、承载能力大，系国内首创，最近通过鉴定。新型圆盘给料机...     

圆盘给料机故障分析及处理

本文简要地介绍了混匀配料工艺对圆盘给料机的工作要求、圆盘给料机在使用过程中发生的和原因分析，并提出了改进的意见和处理方法。     

座式圆盘给料机的设计与计算

本文介绍了座式圆盘给料机的特点和工作原理,详细论述了座式圆盘给料机产量和功率的计算方法,有关计算公式中各系数的选择和确定,论证了国内外座式圆盘给料机驱动电机功率设计计算公式的实际应用与计算结果。     

增加摩擦系数 改善出料能力

型钢供混车间PDX型圆盘给料机受安装偏差影响，出料能力达不到工艺要求，通过焊接φ=18mm螺纹钢，适当增加盘面摩擦系数，大大增加了物料运行中的盘面摩擦力，进而成功地改善了圆盘给料机的出料能力。     

烧结两己料系统宽带给料机的研制与应用

烧结配料用圆盘给料机在实际的生产过程中存在着下料不稳、给料能力有限、维修费用高等缺点。随着生产的扩大和烧结机产能的增加，圆盘给料机已不适应生产的需要，因此研制一种新型给料机一宽带给料机来满足生产的需要。宽带给料机具有下料量稳定、结构简单、给料量大、易于维护等优点，从现场使用情况证明，它完全满足烧结机的正常运行，产量提升明显。     

烧结配料系统宽带给料机的研制与应用

针对烧结配料用圆盘给料机存在着下料不稳、给料能力有限、维修费用高等缺陷，为适应生产的需要，研制了一种新型给料机——宽带给料机。经现场使用证明，宽带路料机具有下料量稳定、结构简单、给料量大、易于维护等优点，完全满足了烧结机正常运行的需要，产量提升明显。     

分料圆盘给料机传动系统的改造

介绍了韶钢烧结厂分料圆盘给料机传动系统改造前存在的问题，以及相应的改造措施和取得效果。     

炼铁厂圆盘给料机改造及应用

分析了2号2000m^3高炉改造期间，新上圆盘给料机的缺点，并对其进行了相应的改造。     

φ2500定量圆盘给料机的分析与改进

本文主要介绍φ2500圆盘给料机在使用与维护过程中的不足之处，并对其进行分析与改进。     

圆盘给料机传动装置的改造

针对韶钢烧结厂圆盘给料机传动系统频繁出现轮齿折断故障的原因进行了分析，并实施了相应的改造。改后两年多来，效果良好。     

马钢第一炼铁总厂烧结圆筒混合机给料圆盘改造

针对马钢一铁烧结分厂二次混合机给料圆盘故障频繁,严重影响生产的问题进行了分析,在此基础上提出了相应的改造方案,并予以实施。改造后运行至今,除日常点检、维护外,从未因故障影响烧结机作业,变频器频率为35 Hz时,给料量可达到420 t/h,完全满足生产需求。     

beta-cell-specific inactivation of the mouse Ipf1/Pdx1 gene results in loss of the beta-cell phenotype and maturity onset diabetes

To study the late beta-cell-specific function of the homeodomain protein IPF1/PDX1 we have generated mice in which the Ipf1/Pdx1 gene has been disrupted specifically in beta cells. These mice develop diabetes with age, and we show that IPF1/PDX1 is required for maintaining the beta cell identity by positively regulating insulin and islet amyloid polypeptide expression and by repressing glucagon expression. We also provide evidence that IPF1/PDX1 regulates the expression of Glut2 in a dosage-dependent manner suggesting that lowered IPF1/PDX1 activity may contribute to the development of type II diabetes by causing impaired expression of both Glut2 and insulin.     

Secreted phospholipase A2-induced neurotoxicity and epileptic seizures after intracerebral administration: an unexplained heterogeneity as emphasized with paradoxin and crotoxin

After intracerebral injection, some toxic secreted phospholipases A2 (sPLA2) can induce epileptic seizures which bases are currently ill known. We undertook the detailed study of the central neurotoxicity of paradoxin (PDX), an analog of taipoxin, in rodents. Since literature strongly suggests a high variability in the sPLA2 epileptogenic properties, we compared, in an acute model, PDX with crotoxin (CTX), known to induce seizures and that may bind to similar neuronal receptors. Related toxic enzymes (ammodytoxin A, ATX A, and CTX subunit CB) and the non neurotoxic sPLA2 from pancreas and PLA2 analog ammodytin L (AML) were also tested. Despite being highly neurotoxic, PDX did not induce either convulsions or long-lasting seizure fits. The results obtained with the other enzymes showed that toxic sPLA2s can effectively be differentiated based on two criteria: the presence of cortically recorded epileptic paroxysmal discharges (E) and convulsions (C). We thus propose to classify the toxic sPLA2s into different groups depending on their epileptogenic properties: E-C-(PDX), E+C+ (CTX, CB), and E-C+ (ATX A). The non toxic AML and pancreatic enzyme were E-C-. Moreover, the results obtained with AML, and preliminarily with chemically inhibited CB, suggested that phospholipid hydrolysis is important to trigger seizures and convulsions. However, PDX and CTX that possess highly different epileptogenic properties exerted comparable, although slightly different, catalytic activities. Similarly, histological evaluations of the brain of PDX and CTX-treated rats (H&E staining, GFAP immunodetection, hsp70 and c-fos mRNA detection) did not provide satisfactory clues to explain these large differences. Further studies are strongly required.     

Mutations in PDX1, the human lipoyl-containing component X of the pyruvate dehydrogenase-complex gene on chromosome 11p1, in congenital lactic acidosis

We have identified and sequenced a cDNA that encodes an apparent human orthologue of a yeast protein-X component (ScPDX1) of pyruvate dehydrogenase multienzyme complexes. The new human cDNA that has been referred to as "HsPDX1" cDNA was cloned by use of the "database cloning" strategy and had a 1,506-bp open reading frame. The amino acid sequence of the protein encoded by the cDNA was 20% identical with that encoded by the yeast PDX1 gene and 40% identical with that encoded by the lipoate acetyltransferase component of the pyruvate dehydrogenase and included a lipoyl-bearing domain that is conserved in some dehydrogenase enzyme complexes. Northern blot analysis demonstrated that the major HsPDX1 mRNA was 2.5 kb in length and was expressed mainly in human skeletal and cardiac muscles but was also present, at low levels, in other tissues. FISH analysis performed with a P1-derived artificial chromosome (PAC)-containing HsPDX1 gene sublocalized the gene to 11p1.3. Molecular investigation of PDX1 deficiency in four patients with neonatal lactic acidemias revealed mutations 78del85 and 965del59 in a homozygous state, and one other patient had no PDX1 mRNA expression.     

烧结机扇形给料料门的结构特点

分析了老式主、辅料门的缺点，为解决此问题，我们开发出了一种新型的扇形给料料门，本文介绍了该新型料门的结构及其优点。     

包钢624m~2大型带式球团焙烧机设计创新与应用

包钢新建成一条国内最大的624m~2大型带式焙烧机球团生产线,年产氧化球团500万t。在设计过程中,对风流系统进行了优化设计,自主设计开发了多项新型设备,如大型球团干燥窑、往复式布料机、回转支撑造球机和稳流给料斗等,并集成应用了立式强力混合机和高压辊磨机等多项国内外大型装备。设计过程中充分考虑了节能环保因素,生产能耗低,粉尘排放、噪音污染均维持在较低水平,除尘灰二次利用,无固体废弃物外排。自2015年底投产以来,设备运行稳定,生产指标良好,球团的TFe质量分数达到65%以上,抗压强度不低于3 100N,工序能耗为17.05kg/t,达到国际先进水平,实现了良好的经济社会效益。