Grain-boundary diffusion and precipitate trapping of hydrogen in ultrafine-grained austenitic stainless steels processed by high-pressure torsion

This study was conducted to clarify the effects of grain boundaries and precipitates on room-temperature hydrogen transport in two types of austenitic stainless steels with ultrafine-grained structures produced by high-pressure torsion (HPT) and subsequent annealing. The grains in the Fe-25Ni-15Cr (in mass%) alloy containing Ti and the Fe-25Cr-20Ni alloy were refined by the HPT-processing to ∼150 and ∼85 nm, respectively. The high-temperature annealing after the HPT processing led to the precipitation of η-Ni₃Ti for the former and σ-FeCr for the latter. In the HPT-processed specimens, hydrogen diffusivity was enhanced through short-circuit diffusion because of the increased population of grain boundaries in comparison with the increased opportunity of hydrogen trapping on dislocations. As for the post-HPT-annealed specimens having the precipitates, the hydrogen diffusion was hindered by the hydrogen trapping on η-Ni₃Ti precipitates, but was not affected by σ-FeCr precipitation. This depends on the affinity between hydrogen and constituting elements.     

Functional cooperation of cyclin C and c-Myc in mediating homotypic cell adhesion via very late antigen-4 activation and vascular cell adhesion molecule-1 induction

Very late antigen-4 (VLA-4)/vascular cell adhesion molecule-1 (VCAM-1) are a pair of adhesion molecules mediating cell-cell interaction. The binding activity of each depends on its surface expression, yet integrin activity can also be modulated through inside-out signaling. However, the specific intracellular molecules involved in modulating integrin VLA-4 activation via inside-out signaling or in regulating VCAM-1 expression are poorly understood. We show here that constitutive coexpression of cyclin C and c-Myc in hematopoietic BAF-B03 cells induces homotypic cell adhesion, which results from enhanced VLA-4 ligand-binding activity and induced expression of VCAM-1. Furthermore, regulation of cell adhesion appears to be a feature unique to cyclin C, but not other G1 cyclins, E and D3, and its regulatory function is independent of CDK8 kinase activity. Our results provide a novel role for cyclin C and c-Myc in the regulation of cell adhesion through distinct mechanisms.     

激光在金属壳雷管编码中的应用

提出激光在金属壳雷管外表进行13位阿拉伯数字编码,应用计算机软件、硬件、激光、精密机械、自动控制于一体,生产效率高,稳定可靠,无污染.     

东乡铜矿的环保综合治理

介绍东乡铜矿井下水的治理和综合利用、井下废石的处理以及选矿尾砂的综合应用 ,井下高温毒气的治理、尾矿坝的复土植被并继续为生产服务等环保综合治理情况。     

水相析晶点对乳化炸药稳定性的影响

文章采用对乳化炸药水相析晶点的测定方法，研究了制备乳化炸药的几种水相析晶点对其稳定性的影响t最后得出了相应的结论。结果表明乳化炸药水相析晶点越低，乳化炸药越稳定，基质水溶值也越小；经16次高低温循环，乳化炸药的殉爆距离仍达到20mm。     

提高选铜回收率的流程改造

在矿石性质和粒级分析的基础上 ,利用现有设施 ,进行流程改造 ,提高选铜回收率 ,为企业资源利用提供有利的依据     

永平铜矿网络工程的设计与实现

本文简略地介绍了企业局域网的设计与实现 ,以及网络系统的安全管理 ,并结合实际制定了具体的数据备份措施及恢复方案     

Analysis of the stabilization of hen lysozyme by helix macrodipole and charged side chain interaction

In the N-terminal region of the alpha-helix of the c-type lysozymes, two Asx residues exist at the 18th and 27th positions. Hen lysozyme has Asp18/Asn27 (18D/27N), and we prepared three mutant lysozymes, Asn18/Asn27 (18N/27N), Asn18/Asp27 (18N/27D), and Asp18/Asp27 (18D/27D). The stability of the wild-type (18D/27N) lysozyme supported the existence of a hydrogen bond between the side chain of Asp18 and the amide group at the N1 position in the alpha-helix, while the stability of the 18N/27D lysozyme supported the presence of the capping box between the Ser24 (N-cap) and Asp27 residues. Although electrostatic repulsion was observed between Asp18 and Asp27 residues in 18D/27D lysozyme, the dissociation of each residue contributed to stabilizing the B-helix in 18D/27D lysozyme through hydrogen bonding and charge-helix macrodipole interaction. This is the first evidence that two neighboring negative charges at the N-terminus of the helix both increased the stability of the protein.     

精制盐代替原盐生产煤矿许用铵梯炸药

文中以精制盐加工工艺理论为指导，进行了精制盐代原盐，取消原盐焙烧制造煤矿许用铵梯炸药的尝试。精制盐替代原盐具有降低材料成本，概治环境污染，简化工艺过程，提高炸药组分初检合格率等优点。     

回路阻抗变化影响电能计量准确性

文章从理论上分析讨论测量回路阻抗变化对三相三线电度表电能计量准确性的影响 ,指出了在实际运行中只有平时加强维护管理 ,尽量保持测量回路的阻抗值对称与稳定 ,使电流互感器二次侧的相位角与一次侧的相位角保持一致 ,才能有效保证电能计量的准确性