我国内螺纹铜管的生产技术与发展方向

本文论述了我国内螺纹铜管业生产、工艺、产品技术条件、齿型及市场现状 ,提出了内螺纹铜管的研发方向。     

碳,氮对氧化锆相结构稳定性的作用

利用热处理研究了碳、氮对氧化锆相结构和相变的影响。实验结果表明：碳、氢原子在高温下可以渗入到氧化锆中去，阻止了氧化锆高温相（四方相和立方相）在冷却过程中向低温相（单斜相）的转变。     

Identification of Bioactivity,Volatile and Fatty Acid Profile in Supercritical Fluid Extracts of Mexican arnica

Supercritical fluid extraction (SFE) is a sustainable technique used for the extraction of lipophilic metabolites such as pigments and fatty acids. Arnica plant is considered a potential candidate material with high antioxidant and antimicrobial activities. Therefore, in this study, a locally available Heterotheca inuloides, also known as Mexican arnica, was analyzed for the extraction of high-value compounds. Based on different pressure (P), temperature (T), and co-solvent (CoS), four treatments (T) were prepared. A maximum 7.13% yield was recovered from T2 (T = 60 °C, P = 10 MPa, CoS = 8 g/min), followed by 6.69% from T4 (T = 60 °C, P = 30 MPa, CoS = 4 g/min). Some bioactive sesquiterpenoids such as 7-hydroxycadalene, caryophyllene and δ-cadinene were identified in the extracts by GC/MS. The fatty acid profile revealed that the main components were palmitic acid (C16:0), followed by linoleic acid (C18:2ω6c), α-linolenic acid (C18:3ω3) and stearic acid (C18:0) differing in percent yield per treatment. Antibacterial activities were determined by the agar diffusion method, indicating that all the treatments exerted strong antibacterial activity against S. aureus, C. albicans, and E. coli strains. The antioxidant capacity of the extracts was also measured by three in vitro assays, DPPH, TEAC and FRAP, using Trolox as a standard. Results showed high antioxidant capacity enabling pharmaceutical applications of Mexican arnica.     

社会能转化与劳动价值

用自然科学与社会科学相结合的方法，通过对传统经济理论的分析，引入社会能概念，把复杂的社会经济问题投影到能量空间进行研究，讨论社会能测度的劳动及价值，并用社会能描述社会生产过程。     

电力变压器铁芯磁场和损耗分布的三维数值方法与实施(第三部分:铁芯搭迭区)

在第一和第二部分的基础上,本文着重讨论铁芯搭迭区局部磁场的分析模型和数值方法,并根据计算结果探讨各种搭迭形式及相关因素对磁场和损耗的影响,由此得出一些有利于铁芯搭迭设计的合理化建议。     

紫金山铜金矿黄铁矿环带结构特征

主要通过对紫金山铜金矿成矿期环带状黄铁矿的特征研究,来探讨成矿期地质环境及成矿作用。利用电子探针对不同深度矿化带中具环带结构黄铁矿的内核和环带中的微区进行化学成分分析,发现环带黄铁矿属于亏铁富硫型。Ni-Co(-As)图解显示环带状黄铁矿为火山—热液成因;环带是主要载金部位,金以纳米级自然金颗粒形式存在。结合本矿矿区地质、矿相学、岩石地球化学特征,认为本矿成矿期环带黄铁矿的形成与本区燕山晚期的火山—岩浆侵入活动密切相关,体现紫金山铜金矿的成矿流体是燕山晚期富含Cu、Au、Pb、Zn等成矿元素的火山热液叠加在燕山早期具有W、Sn、Mo、Bi等矿化的紫金山复式花岗岩岩体上。