旧沥青混合料再生技术在修补路面坑槽中的应用

介绍了旧沥青混合料再生技术的先进性、施工工艺的简便性、经济实用性和发展前景。     

EFFECT OF LOW SELENIUM ON CHONDROCYTE DIFFERENTIATION AND DIFFERENTIAL EXPRESSION OF COLLAGEN TYPES Ⅰ , Ⅱ AND X IN ARTICULAR CARTILAGE FROM MINI-PIGS

Objective According to the distribution of low selenium areas, low nutrition state of the residents and the affecting cartilage growth and articular cartilage of Kashin-Beck Disease(KBD),the chondrocyte differentia- tion and differential expression of collagen types Ⅰ , Ⅱ and Ⅹ in articular cartilage from Chinese mini-pigs treated with low selenium were investigated in order to gain insight into the effects of these conditions on chondrocyte differ- entiation in KBD cartilage. Mothods Eleven male juvenile mini-pigs, aged from 4 weeks to 6 weeks after birth, were divided into 3 groups. The Se content in the diet of the “low Se” group was 0. 035mg/kg diet, and 0. 175 mg/kg diet in the control. For Se-supplemented group 0. 390mg /kg diet was added. The content of Se in blood was assayed at the beginning and at the end of each experiment. Samples of articular cartilage were taken from the right femur condylus, and collagen types Ⅰ , Ⅱ and Ⅹ in articular cartilage were analyzed by immunohistochemistry and in situ hybridization. Results ①All cartilage samples from juvenile mini-pigs fed with low selenium diet revealed a re- duction in type Ⅹ collagen mRNA expression in the hypertrophic chondrocytes as shown by in situ hybridization, and reduced type Ⅹ collagen deposition in the lower hypertrophic zone as shown by immunohistochemistry. ②Addition of selenium to the diet restored the type Ⅹ collagen to normal level. ③Type Ⅱ collagen was evenly distributed over the entire articular cartilage in all experimental and control groups. Type Ⅱ collagen mRNA signals were most prominent in the upper articular layer as well as in the hypertrophic zone in all groups. Type Ⅱ collagen expression was restrict- ed to the zone of endochondral ossification in all experimental groups and the control. Conclusion Low selenium has an down-regulatory role on the synthesis and deposition of collagen type Ⅹ in hypertrophic chondrocytes in articular cartilage of mini-pigs. Supplement of the low Se diet with additional Se restored the signals of collagen type Ⅹ to nor- mal levels. These findings indicate that selenium deficiency may disturb chondrocyte differentiation to hypertrophic cells in the growth plate,and worthy to be investigated further.     

公路桥梁战时安全基本措施研究

公路桥梁是交通基础设施的重要组成部分,其战时安全备受关注。在分析公路桥梁战时安全内涵的基础上,针对战时公路桥梁的破坏特点,从提高抗打击能力和加强快速修复能力两个方面提出公路桥梁的战时安全措施,有助于保障公路桥梁的战时安全。     

基于C/S结构的机车中修检修管理信息系统的设计

介绍了三层C/S结构的机车中修检修管理信息系统,阐述其系统的设计方案、结构、功能、主要特点和系统的运行效果.该系统实现了对机车检修作业过程的监控与管理,实现了检修作业过程中检修数据、检修信息的记录与分析,极大的规范了机车检修过程、提高了机车检修质量.该系统的运用是铁道部建设数字化机务段的重要组成部分.     

市域铁路灵昆修造基地工艺设计创新与实践

依托温州市域铁路线网的唯一高级修基地——灵昆修造基地项目,深入研究市域车辆新造和检修工艺,在修造基地总体规划阶段创新地提出"修造合一"的定期检修工艺布局.不同于国铁修整列架车检修的模式,基于新造和检修的工艺流程,提出车辆解编、分体检修的流水修总体工艺方案,可实现包括总装、涂装和单车试验调试三大工艺板块的新造和检修资源共...     

沥青路面坑槽修补工艺研究

根据沥青混凝土路面坑槽破坏的机理,为达到实现沥青路面坑槽修补的最终目的,结合对高速公路日常养护中坑槽修补的各种材料和相关工艺的应用研究,提出获得理想维修效果的具体要求,以期对坑槽修补材料和修补工艺的应用提供一定的指导.     

蔷薇河大桥的维修与加固

根据蔷薇河大桥病害情况,针对不同的病害成因进行分析,制定维修加固方案,并介绍维修加固施工工艺,可为类似工程提供借鉴。     

混凝土外观质量的分析和修复办法

结合施工经验,对砼的表面缺陷,如表面裂缝、表面破损、表面颜色不均匀、表面漏筋的内因进行分析,并提出有针对性的预防措施及对既有缺陷的修复处理办法,可为提高混凝土的外观质量提供参考和依据。     

超深搅拌桩在盾构常压换刀中的应用

南水北调中线穿黄工程中要进行盾构刀盘常压下修复的工作,须在盾构机周边进行防渗墙和地基加固的施工。该文阐述了采用超深搅拌桩方案进行盾构常压换刀的方案选择过程,并介绍了其施工工艺及主要设计参数。文章最后总结了施工中存在的问题及其改进措施。     

沥青路面坑槽修补研究

该文通过对沥青路面坑槽破损形式及成因的研究,将坑槽分成表面层产生坑槽、表面层和中面层同时产生坑槽、底面层和基层间产生坑槽以及刚性组合式路面上产生坑槽四种,并对目前的坑槽修补技术进行了全面介绍和分析,包括挖补法、填料法、喷补法、热再生法四种修补技术。最后对坑槽修补时的步骤及工艺进行了详细阐述。