基于层次分析价值工程法的数字营区改造方案优选

针对数字营区改造中因改造项目多、杂而造成的改造方案难以选择的现状,引入层次分析和价值工程结合的方法,确定改造方案的功能系数,达到以最低的改造成本,获得最好的改造效益的目的。     

CT引导下经皮肺穿刺活检术诊断肺癌准确性的回顾性分析

【摘要】 目的 探讨CT引导下经皮肺穿刺活检术（PTNB）诊断非小细胞肺癌（NSCLC）准确率及其影响因素。方法 回顾性分析2010年1月1日至2016年11月1日有手术病理结果的NSCLC患者203例，所有患者在术前均行CT引导下PTNB取得组织标本病理。计算穿刺活检诊断准确率，并分析影响穿刺活检诊断准确率的因素。结果 ①CT引导下PTNB取得的小标本与手术大标本的病理结果符合率为92.6%（188/203）；鳞癌和腺癌类型的符合率最高，分别为100%、97.5%，大细胞癌类型的符合率20%。大、小标本对肺腺癌、鳞癌的分型诊断差异无统计学意义（k＝0.872、P＝0.250）。②χ2检验结果显示观察因素中只有病灶大小是穿刺活检诊断准确率的影响因素（P=0.008）。结论 CT引导下PTNB与手术大标本在NSCLC的诊断方面有较高的符合率，值得在临床推广；病灶大小是穿刺活检诊断准确率的重要影响因素之一。
     

Research progress on chemical modification of silk fibroin and its applications北大核心CSCD

Mulberry silk is composed of the two major parts of two triangle-like silk fibroin fibers and sericin covering the fibers and a few lipids. After removing the sericin on the raw silk what is left is the silk fibroin fiber. Silk fibroin is the main part of silk accounting for about 75% of the total weight. Silk fibroin contains 18 natural amino acids such as glycine Gly alanine Ala serine Ser serine aspartic acid Asp and tyrosine Tyr . The secondary structure of silk fibroin has three main conformations α-helix β-fold and random coil. Under certain conditions the three conformations can transform into each other and change the mechanical properties of the silk fibroin material. Silk fibroin extracted from silk fiber is a natural polymer with biocompatibility and biodegradability. It can be further processed into different forms of materials nanoparticles films hydrogels sponges etc. It has been applied in many fields such as biomedicine and cosmetics. In order to meet the needs of different fields researchers have conducted further chemical modification treatment based on the original excellent properties of silk fibroin. Meanwhile the active groups on various amino acid residues in silk fibroin also provide chemical reaction sites for the chemical modification of silk fibroin. The chemical modification methods of silk fibroin mainly include amino acid residue modification macromolecular grafting modification and crosslinking reaction modification. Among them amino acid residue modification can modify protein amino acid residues by chemical reagents and some groups can be introduced into the side chains of silk fibroin macromolecules. Grafting modification of silk fibroin macromolecules is one of the main means to bind functional compounds to silk fibroin macromolecular chains. The properties of grafted silk fibroin are affected by the type and grafting rate of the grafts. The chemical crosslinking reaction modification of silk fibroin macromolecules is to make the macromolecular chains connected by covalent bonds and form a network structure by means of crosslinking agents enzymes or ultraviolet irradiation. The cross-linking reaction can not only form covalent bonds within and between the molecular chains of silk fibroin thus changing its structural properties and improving its stability but be used to form covalent bonds with other polymers. At present the chemical modification of silk fibroin is mainly applied in the fields of silk textiles biomedicine and environmental science. In the field of silk textiles graft copolymerization modification of vinyl and other monomers crosslinking agent modification and other methods are used to overcome the shortcomings of silk like being easy to wrinkle. The graft modified monomers mainly include ethylene methacrylate and methylacrylamide. The active groups on crosslinking agents such as polycarboxylic acid / anhydride and epoxide are covalently combined with carboxyl hydroxyl and amino groups on macromolecules of silk fibroin to improve the wrinkle resistance of silk fabrics. In the field of biomedicine silk fibroin materials with appropriate chemical modification have better biological activity drug delivery ability antimicrobial properties and mechanical properties. The optimization of these properties enables silk fibroin materials to show great potential in drug control delivery tissue regeneration and wound repair. The applied research in the field of environmental science mainly focuses on the adsorption separation and catalysis of impurities in water. Therefore the modification of amino acid residues grafting and cross-linking of protein macromolecules can change some important properties of silk fibroin and meet the requirements of various applications and functionalization of silk fibroin. In many fields of chemical modification and application of silk fibroin protein fruitful results have been achieved which has laid a good foundation for the further development of related fields and also shows that the chemical modification of silk fibroin material has great potential and application prospects. However there are still some problems that need to be overcome and further improved in the current chemical modification methods such as mild modification conditions and accurate adjustment of the degree of modification which will be the research direction of related fields in the future. © 2022 Authors. All rights reserved.     

加气混凝土水化产物组成及其形貌研究

本文通过采用XRD衍射方法和SEM扫描电镜方法对加气混凝土水化产物的种类、结构和形貌进行研究.结果发现：经蒸压后水化产物以托勃莫来石、硅酸钙和水化石榴子石为主,内部由连通状和封闭状的“蜂窝状”椭圆形小孔构成,孔壁中有许多的“褶皱状”的产物,尺寸在200～600um之间,孔壁的厚道在20um左右.在气孔内壁,产物多为一簇簇的柳叶状托勃莫来石及少量的水化石榴子石,托勃莫来石长约2～3μ m,宽约1 μ m,水化产物密集丛生,相互交插连接,形成致密的网络状微观结构.     

对大型建筑设计院转型经营的探讨(下)——转型后总承包模式选择的建议

最近几十年,随着我国加入世贸组织和经济全球化进程的加快,我国建筑行业呈现出快速发展的态势,同时也为了加入WTO以后,国际工程市场的变化,满足我国建筑企业走向国际市场的需要,建筑设计企业向总承包转型的推进势在必行。本文结合自己工作实践和对相关政策法规的学习,提出设计企业向工程总承包转型模式的选择建议,供同行参考。     

西昌钢钒A高炉炉况失常的治理

西昌钢钒A高炉发生风管烧穿事故紧急休风后,发生炉况失常。究其原因,主要是紧急休风后恢复操作不当,且炉况反复,导致顺行变差,风量萎缩,长期慢风又造成炉缸堆积。通过提高鼓风动能、发展两道气流、提高炉温、配加锰矿及萤石洗炉、持续改善焦炭质量等措施,使炉况逐步恢复正常。认为冶炼钒钛磁铁矿高炉炉况失常的治理,应加强风速及鼓风动能的监控,确保初始煤气流分布合理。     

海洋生物副产品中胆固醇提取工艺的研究

为解决胆固醇提取原料的来源限制,开发新工艺,采用钙盐络合胆固醇,先皂化预处理,成钙盐、渗滤、浓缩、溶解结晶和重结晶,得到高含量胆固醇。以胆固醇的收得率为参考指标,优化了氢氧化钠的最佳添加量为20%、氯化钙的最佳添加量为25%、丙酮的最佳添加量为钙盐质量的10倍,胆固醇的收得率为15%,所得产品指标达到147℃胆固醇的质量要求。