感应加热弯管热处理前后热影响区组织和性能的变化

对X70及X80中频感应加热弯管热影响区冲击韧性的变化做了深入的探讨。首先通过生产数据统计做趋势分析;然后采用热模拟试验对各细分区域进行热模拟与力学性能试验,与趋势相验证;最后对热影响区从原始态到调质态过程中各阶段的金相组织变化做了充分的分析,从组织形态的角度阐述了性能变化机理。试验结果表明,感应加热弯管热影响区的粗晶区、细晶区和重叠区在调质过程前后,其性能与金相组织均发生了显著的变化。针对此现象,笔者也对弯管相关标准的具体条款提出了自己的建议和观点。     

深海管线用高钢级厚壁直缝埋弧焊管研制

对深海管线用钢管的研制背景及技术目标进行了详细阐述。通过采用低C高Mn-Nb-Ti合金化的成分设计和合理的TMCP工艺控制,开发出具有高强度、低屈强比和优异低温韧性良好匹配的X70级36.5 mm厚壁管线钢。采用JCOE制管工艺试制的X70级准914 mm×36.5 mm直缝埋弧焊管,其管体及焊接接头的拉伸性能、断裂韧性及硬度等指标全部满足DNV-OS-F101标准要求,主要性能指标达到了研制技术目标要求。     

Renzo Piano: Poet of Technology

The architecture of the Renzo Piano Building Workshop (RPBW) is renowned internationally for the formal refinement of its components and detailing as well as for its sensitive responses to context, both in terms of its physical surroundings and local construction traditions. But, as architectural author and Piano specialist Peter Buchanan reminds us, the central concern of the practice remains focused on the original core impetus of expandingthe bounds of what technology and materials can achieve.     

Complex of HIV-1 Integrase with Cellular Ku Protein: Interaction Interface and Search for Inhibitors

The interaction of HIV-1 integrase and the cellular Ku70 protein is necessary for HIV replication due to its positive effect on post-integration DNA repair. We have previously described in detail the Ku70 binding site within integrase. However, the integrase binding site in Ku70 remained poorly characterized. Here, using a peptide fishing assay and site-directed mutagenesis, we have identified residues I72, S73, and I76 of Ku70 as key for integrase binding. The molecular dynamics studies have revealed a possible way for IN to bind to Ku70, which is consistent with experimental data. According to this model, residues I72 and I76 of Ku70 form a “leucine zipper” with integrase residues, and, therefore, their concealment by low-molecular-weight compounds should impede the Ku70 interaction with integrase. We have identified such compounds by molecular docking and have confirmed their capacity to inhibit the formation of the integrase complex with Ku70. Our data demonstrate that the site of IN binding within Ku70 identified in the present work may be used for further search for inhibitors of the integrase binding to Ku70.     

羟基磷灰石纳米颗粒诱导巨噬细胞凋亡及其与HSP70相互关系的研究

研究羟基磷灰石纳米颗粒(HAp nanoparticles)引起巨噬细胞凋亡,及其与热休克蛋白Hsp70的相关性.THP-1单核细胞株经PMA诱导成为巨噬细胞,分别加入0、20、100μg/ml HAp纳米颗粒,培养24h后经PI和AnexinV染色,在荧光显微镜下观察,用流式细胞仪检测细胞的凋亡情况,应用western blot 方法检测Hsp70蛋白分子表达的改变.显微镜观察显示THP-1单核细胞株能被诱导成巨噬细胞.荧光显微镜显示20、100μg/ml HAp纳米颗粒组凋亡的阳性信号明显强于0μg/ml对照组;流式细胞仪检测结果也证实HAp纳米颗粒组比对照组凋亡率明显增高(P1＜0.0001,P2＜0.0001),且凋亡的程度呈浓度依赖性(P3=0.025).Western Blot 检测显示20、100μg/ml HAp纳米颗粒组较对照组Hsp70蛋白表达增加,并且随颗粒浓度增高而表达增加.     

管线钢焊接局部脆化区的M-A组元

采用焊接热模拟、金相分析及透射电镜研究了X70管线钢焊接局部脆化区M-A组元的形态、数量、分布及在透射电镜下的精细结构、形貌特征.结果表明,粗晶区M-A组元以块状为主,有少量呈长条状.再热临界粗晶区的M-A组元数量急剧增多,基本都是狭长的长条状,分布比较密集,M-A组元相邻间距较小,平均弦长较大,为4.21 μm.透射电镜下条状M-A组元一般分布于贝氏体铁素体的板条界面处,块状M-A组元有的呈不规则形状,有的呈三角形.M-A组元中马氏体的精细结构为孪晶亚结构.     

X70钢级热轧无缝管线钢热处理工艺研究

分析了X70钢级热轧调质无缝管线钢热处理工艺及性能和组织的变化,该管线钢的性能能达到美国API 5 L标准.试验结果表明:该钢在920℃保温38 min水冷,550℃回火78 min后有较高的强度和韧性.     

聚-DL/L-丙交酯(30DL/70L)纳米纤维的电纺研究

对生物可吸收聚-DL/L-丙交酯(30DL/70L)体系进行了静电纺丝.研究了聚-DL/L-丙交酯(30DL/70L)的浓度,加料速度,电压,喷头与接收体之间的距离等因素对纤维形态的影响,制备出纳米纤维膜,并用扫描电镜(SEM)等对纤维膜进行表征.结果表明,电纺溶液浓度和溶剂对纤维直径影响比较明显,减小电纺溶液浓度和采用复合溶剂CHCl3/DMF可得到更细的纳米纤维;一定范围内适当的增加电压、减小距离和减小加料速度有利于减小纤维直径.在聚-DL/L-丙交酯(30DL/70L)浓度为5g/100mL溶剂、加料速度1mL/h、喷头与接收体之间的距离6cm、电压15kV电纺条件下,可制备直径50nm左右的聚-DL/L-丙交酯(30DL/70L)纳米纤维膜.     

Logix5000及Powerflex70在自动配煤控制系统上的应用

介绍了Logix5000及Powerflex70在济南钢铁股份有限公司焦化厂自动配煤中的应用,重点介绍了36台Powerflex70,Logix5000、Powerflex70通讯采用了双冗余的ControlNet可靠通讯方式.