硫化铜精矿制备硫酸铜的试验研究

本文介绍了用内蒙古炭窑口硫铁矿的硫化铜精矿经硫酸化焙烧，硫酸浸出制备硫酸铜的工艺研究，着重阐述了酸浸过程中影响铜浸出率的多种因素。     

骨髓基质干细胞复合PLGA支架修复兔关节软骨缺损

目的探讨骨髓基质干细胞复合PLGA支架对兔关节软骨损伤的修复作用。方法以聚乳酸/聚羟基乙酸共聚物、磷酸三钙制备支架。取新西兰乳兔骨髓分离BMSCs,传代后接种于支架。54只新西兰大白兔,建立膝关节软骨缺损模型,随机分为模型对照组、支架组和支架+BMSCs组。结果光镜示BMSCs在支架内生长良好;膝关节活动度和移植组织的平均厚度与周边正常软骨平均厚度百分比显著高于模型对照组(P<0·01)。结论 PLGA支架复合BMSCs提高了兔关节软骨缺损的修复效果。     

紫外光照射磷钨酸制备金纳米颗粒

以Keggin结构的磷钨酸H3PW12O40为光催化还原剂,以异丙醇为电子牺牲剂,用紫外可见光照射磷钨酸和氯金酸的混合溶液,制备金纳米粒子。采用透射电子显微镜(TEM)、紫外可见吸收光谱(UV-vis)和X射线光电子能谱(XPS)等手段对制备的金纳米颗粒的形貌、粒径大小和结构进行了表征。UV-vis结果表明,随着反应时间的延长,Au的特征吸收峰逐渐红移。制备的Au纳米颗粒有球形、柱形和不规则的多边形,并随着反应时间的延长,粒径逐渐增加,生成的纳米Au为立方面心晶格。     

Folate/folic acid knowledge,intake, and self-efficacy of college-aged women: impact of text messaging and availability of a folic acid–containing supplement

ABSTRACT

Objective: To evaluate the impact of educational text messages (TMs) on folate/folic acid knowledge and consumption among college-aged women, and to evaluate the impact of providing folic acid supplements on folate/folic acid intake among college-aged women. Participants: A total of 162 women (18–24 years) recruited from a university. Methods: The protocol included 3 study visits and a 6-week intervention for 4 groups: control; TM only; supplement only; and TM+supplement. Supplement groups received folic acid–containing supplements. TM groups received 18 folate-related TMs. Participants completed knowledge quizzes, supplement intake questions, a self-efficacy scale, and dietary recalls. Results: Despite receiving the same folic acid education, intake of folic acid and total folate was greater in the supplement groups compared with the non-supplement groups at mid- and post-study. TMs had no impact on any study measure. Conclusion: Provision of a folic acid–containing supplement enhanced short-term folic acid intake, supporting the provision of supplements to this population group.     

泡沫酸性能影响因素及其应用

针对应用常规酸化技术对低渗油层进行改造时,由于返排不彻底对其造成二次污染,故建议使用泡沫酸。并对其一些性能及其影响因素做了详细的介绍,列举了一些在现场的成功经验,以便进一步说明泡沫酸液的优越性能。     

腐植酸盐对吉林稠油乳化作用研究

以乳状液稳定性为指标,在室内评价了腐植酸盐对吉林稠油的乳化作用。结果表明：腐植酸盐可以作为稠油乳化剂使用,具有一定的乳化降黏作用,但因原料、生产工艺不同,乳化性能存在差异。腐植酸盐与氢氧化钠复配使用可大大提高乳化性能。腐植酸盐可有效提高表面活性剂对稠油的乳化效果,其中对非离子表面活性剂的效果最好,对阴、阳离子表面活性剂作用相当。     

试用基团电负性计算结果解释有机酸强度规律

本文用逐级均分法计算了一些基因的电负性，并用此结果解释了以往只定性描述的一些有机酸的强度规律。之后提出了计算方法的一点修正意见．     

Comparison of genomic sequences using the Hamming distance

The paper considers the problem of homogeneity among groups by comparison of genomic sequences. Some alternative procedures that attach less emphasis on the likelihood approach, and more on alternative measures that deal with similar homogeneity problems are considered here. On this approach, a one-sided hypothesis test is considered and the classical ANOVA decomposition can be directly adapted to sample measures based on the Hamming distance, without necessarily going through their second moments. Some results of U-statistics theory will be useful for the decomposition of the test statistic and to find its asymptotic distribution. An application of this test with real data is shown and the p-value of the test statistic is found via bootstrap resampling.     

己二酸实验室制法中高锰酸钾的最佳用量

本试验通过用不同量的高锰酸钾，在弱碱性条件下氧化等量的环已酮制备已二酸，获得不同产率，从而得出高锰酸钾的最佳用量．     

糠醛作原料合成富马酸二甲酯的研究

本文报道了以糠醛为起始原料,先以氯酸钾作氧化剂制得富马酸,再用甲醇进行酯化制富马酸二甲酯的合成工艺,并对影响产率的因素进行了讨论。