果蓬类原料致密成型特征及其机制炭质量分析

以山核桃、油茶和板栗3类果蓬为原料,研究了此类原料与杉木、松木屑在不同配比条件下对果蓬类致密成型特征及其机制炭质量的影响。证实了果蓬类原料因纤维素含量、木质素含量与杉木、松木存在差异,且因较高的灰分含量限制,需与杉木或松木屑等原料在一定配比条件下才可实现良好的致密成型。而配比选择试验结果则表明,果蓬原料与杉木、松木屑混合原料以3:7比例配料为宜;在此条件下,制备的机制炭外形平直无裂缝,得率为 33.85%~36.73%,固定碳含量 79.80%~86.20%,热值28.96~31.92 MJ/kg。     

Glyceride isomerizations in lipid chemistry

Isomerization of isopropylidene glycerol ketals and benzylidene glycerol acetals was studied, and isoraerization equilibria were established. Reaction of benzaldehyde with glycerol gave four benzylidene glycerol isomers, which were separated by column chromatography and characterized by NMR spectroscopy and other methods. Isomerization of 1- and 2-monoglycerides and of 1,2- and 1,3-diglycerides, and their separation by column chromatography, are described. Mechanisms of isomerization in mono- and diglycerides and factors which affect them are discussed. Isomerization of 1- and 2-glycerophosphates and of cyclic glycerophosphates by acid and base was also studied. Hydrolysis products of L-3-glycerylphosphorylcholine and 2-glycerylphosphorylcholine were separated by column chromatography and characterized by periodic acid oxidation, optical rotation, and NMR spectroscopy. No isomerization of unhydrolyzed L-3-glycerylphosphorylcholine and 2-glycerylphosphorylcholine was observed. Evidence indicated that acid-catalyzed hydrolyses of phosphoglycerides are under thermodynamic control whereas most base-catalyzed hydrolyses are under kinetic control.     

纳米阻燃抑烟PVC的研究进展

PVC是一种应用广泛的高分子材料,但因其具有热稳定性差、易燃烧、发烟量大的缺点而限制了发展,因此PVC的阻燃与抑烟成为阻燃科学研究领域的关键问题之一。纳米型阻燃抑烟剂克服了传统型阻燃抑烟剂添加量大、阻燃抑烟效果不明显的缺点,为研究和解决PVC阻燃抑烟提供了一个新途径。本文介绍了PVC纳米阻燃抑烟剂的制备方法、表征手段及其在PVC中的应用以及PVC降解、阻燃与抑烟的表征,最后简要论述PVC阻燃抑烟的发展趋势。     

On Porosity of Carbon Aerogels from Sol-Gel Polymerization of Phenolic Novolak and Furfural

Carbon aerogels were prepared by sol-gel polymerization of phenolic novolak and furfural followed by supercritical drying and pyrolysis. The porosity and morphologies of carbon aerogels were characterized by nitrogen adsorption, apparent density, He- pycnometer method, and transmission electronic microscopy (TEM). Effect of ratios of phenolic novolak to furfural (Ra) and total concentration of reactants (C) in sol-gel step on porosity and morphologies of carbon aerogels was investigated. The carbon aerogels synthesized are rich in meso- and macropores. The Ra determines the cross-linking density of polymers, thereby the compatibility of the polymers, and ultimately the shrinkage of gels in the drying and pyrolysis. The network sizes and the porosity of organic and carbon aerogels are mainly determined by Ra. The C has no effect on volume shrinkage of gels in drying and pyrolysis and has only dilute effect in determining bulk density of organic and carbon aerogels, and ultimately the porosity of carbon aerogels. Conversion of mesopores to micro- and macropores is observed, which is related to combination of C and Ra, and determines the partition of micro-, meso- and macropores.     

Price evolution of foods and nutriments in Mexico from 1973 to 2004

The aim of this study was to know the price changes of foods and nutriments in México during the last three decades. To this end, two sets of data were analyzed: the National Consumer Prices Index for 1973 to 2003, and quotations of food prices for 1990, 1995, 2000 and 2004. Cost estimates were calculated for 100 kcal, 10 g of saturated fat, 100 mg of cholesterol, 10 g of fiber and 1 mg of iron. Regression models were used to analyze the association between nutrient and energy's costs and energetic and nutrimental densities. Our results lead to infer that that in M6xico, the structure of foods prices differed between the eighties and the nineties decades. In the former, vegetables and corn and wheat derived foods had the lowest price increment, whereas their price had the largest increment in the following decade. On the other hand, the prices of fresh meat of cattle and pig, and of fish and seafood rose during the eighties but became cheaper during the nineties. The differences in prices of the meat are inversely related to their energy density and nutrimental value: lean meat became more expensive that those with more fat (i.e., more energy and cholesterol). Canned fish (tuna and sardine), eggs and poultry became cheaper at the turn of the eighties. The prices of the majority of oils and fats have increased less than the inflation of the group of food. Processed and industrialized foods became cheaper than the fresh ones. The energy density of the foods is negatively correlated to their cost. The implications of our results are discussed in terms of public policies.     

流行性腮腺炎病毒疫苗株WM84六代次基因序列分析

目的分析6个代次流行性腮腺炎病毒疫苗株WM84融合蛋白(F)、血凝素神经氨酸酶蛋白(HN)和疏水蛋白(SH)的基因序列,并与Jery-Lynn(JL)株和ME株进行比较。方法WM84株病毒在原代鸡胚成纤维细胞(CEF)上连续传代至12代,观察各代病毒的培养特性,测定2、7、9、10、11、12代主要结构蛋白基因及高变区SH基因序列,与GenBank中参考毒株JL2、JL5和ME株进行比对,分析其核苷酸序列及相应氨基酸序列的差异,并构建系统进化树。结果WM84株病毒在CEF上连续传代至12代,其培养特性及病毒滴度基本稳定。与WM84株2代相比,其各代在主要蛋白基因区域有散在的核苷酸变化。7～12代病毒HN、F和SH基因与2代相比,核苷酸同源性分别为97.0%～100%、97.0%～100%及94.0%～100%;氨基酸同源性分别为98.3%～100%、97.2%～100%及94.1%～100%。2～7代病毒,HN、F和SH基因氨基酸与JL2株同源性为98.8%～99.5%,与JL5株同源性为94.1%～98.3%,传至11、12代,与JL5株同源性达99.8%～100%。结论WM84株2～7代病毒蛋白基因与JL2株十分相似,但在后续传代过程中出现了JL2株向JL5株转化的倾向。WM84株病毒在传代过程中HN及F基因结构基本稳定。     

海水海砂混凝土力学性能与耐久性研究综述

远海工程建设面临钢筋混凝土易腐蚀、河砂和淡水匮乏等难题。国内外学者选择资源丰富的海水海砂代替淡水河砂制备混凝土,并研究其工作性能、力学性能及耐久性能。海水海砂中高含量的氯盐会加快水泥水化和凝结,导致早凝和早期强度提高,但后期增长变缓,最终强度与淡水河砂混凝土相近。海砂中少量的贝壳对混凝土工作性能和力学性能影响不大。海水海砂混凝土中的氯离子传输及结合方式更为复杂,其不同于内掺型氯离子,由此导致海水海砂混凝土中的钢筋锈蚀机理改变。辅助胶凝材料、复合型阻锈剂及纤维增强复合筋等为海水海砂混凝土结构应用提供了保障。     

颗粒介质用机械密封热力耦合变形及摩擦磨损研究

在含有颗粒介质的工作环境中下,硬质材料配对机械密封环的热力耦合变形和摩擦磨损对机械密封的泄漏和使用寿命起着至关重要的作用。考虑动静环和颗粒介质的摩擦,试验测定了摩擦系数,建立了动静环热力耦合的有限元计算模型,研究了WC-Co硬质合金和无压烧结碳化硅（SSiC）陶瓷两种硬质材料密封的温度场和端面变形规律,分析了不同工况下的密封间隙变化规律。试验测试分析了密封环温度、磨损前后的泄漏及表面粗糙度,讨论了端面的磨损机理,验证了计算模型的准确性。结果表明：考虑动环磨粒摩擦热的有限元模型能准确地预测密封的温度和端面变形;耦合作用下动静环端面呈现外径脱离、内径贴合的变形,且变形差异程度随压差和转速的增大而加剧;变形导致端面磨痕分布不均匀,内径磨痕较严重。WC-Co硬质合金配对密封环的端面变形小、泄漏量小,高硬度WC颗粒对Co基体能产生很好的“阴影效应”,具有良好的耐磨粒磨损性能。SSiC陶瓷材料韧性差,易产生片状磨屑,形成过渡型磨粒磨损,材料耐磨性较差,泄漏量增加明显。在磨粒工况下,WC-Co硬质合金机械密封具有泄漏小、耐磨性强的特点。研究结果为颗粒介质中机械密封的材料应用及设计优化提供了参考。     

高频电磁场抑垢效果的实验研究

用高频电磁法进行换热设备的抑垢处理,具有应用方便、投资小、无污染等优点,是一种极具发展前景的应用技术。但有效评价高频电磁场在线抑垢效果的策略及手段还很欠缺。基于污垢热阻值的在线监测技术,通过自主研发的在线监测评价实验系统采集和处理模拟换热器中研究管段的流体出入口温度、流速和壁温,得到加磁处理与未加磁处理的污垢热阻变化趋势以及加磁处理的抑垢率。同时测量和分析了溶液电导率的变化,完成了高频电磁场的抑垢效果的客观评价,并取得了良好的预期结果。     

Lipide content of rice bran

Summary The examination of rough rice of eight varieties grown in three locations each showed variations in milling yields and lipide contents of bran and of the true pericarp and bran fraction which are attributable to the influence of variety and environment of growth. The average values found on the moisture-free basis were 6.0% bran and 5.4% true pericarp and germ fraction for the rough rice and 19.5 and 21.8% lipides in the bran and the true pericarp and germ fraction, respectively. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

The use of liposomes in the modification of polycaprolactone fibers

Polycaprolactone is fully bioresorbable and biocompatible material. Liposomes containing nanocopper, nanosilver, and nanogold are known to have antifungal and antibacterial properties and to further aid in the synthesis of collagen and elastin in the skin. It is possible to combine the properties of polycaprolactone fibers and liposomes in new approaches to deliver active substances through cosmetics and medicines. The aim of the research was to examine the possibility of simple modification of PCL fibers with use of nanocopper, nanogold, and nanosilver incorporated liposomes. The size and the type of the liposomes were examined using optical microscopy and DLS techniques. The fibres modified with liposomes were investigated using SEM and FTIR techniques. Additionally the contact angle measurements were performed. The study shows an innovative method of modifying polycaprolactone nonwoven textiles. This combination of PCL fibers and liposomes allows easy and efficient preparation and delivery of active substances to a particular location. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43299.     

有机氯农药、有机磷农药的EIMS、NCIMS和PCIMS质谱

阐述31种农药在3种电离方式：电子轰击质谱(EIMS)、正化学电离质谱(PCIMS)和负化学电离质谱(NCIMS)下的质谱特征和裂解规律，为农药残留的筛选和结构确证奠定基础。分别测定18种有机氯农药、13种有机磷农药的电子轰击质谱(EIMS)，正化学电离质谱(PCIMS)和负化学电离质谱(NCIMS)。在EIMS中，有机氯农药主要产生[M—Cl]^ 、[M—HCl]^ 离子，有机磷农药主要产生磷酸基和磷酸酯基离子；在NCIMS中，[Cl]^-或[HCl2]^-离子是有机氯农药的基峰，有机磷农药主要产生磷酸酯基负离子，某些芳香硫代磷酸酯还可产生重排离子；而在PCIMS中．大多数农药的灵敏度较低．没有观察到质谱。     

世界油气主产国油气资源管理的基本经验及启示

油气是重要的战略资源,关系国计民生。随着工业化和城镇化的加速推进以及汽车进入普及期,我国油气供需形势日趋严峻。解决我国油气供应不足的问题。应首先立足于开发利用国内的油气资源,不断提高自给水平,然而却存在管理体制和政策的掣肘。世界油气主产国都不断改善其油气资源开发利用的管理体制与政策,促进更加有效与合理地开发利用和保护油气资源。本文总结了该领域的国际经验,从加强油气资源法律法规体系建设、促进油气资源管理体制改革、完善油气资源矿业管理等方面提出了对我国的启示和改革建议。     

催化裂化（FCC）油浆作煤直接液化溶剂的研究进展

煤制油工艺等煤炭清洁高效转化技术是能源化工领域的研究热点,溶解性好、提供/传递氢能力强且热稳定性高,其溶剂选择、使用是影响煤制油工艺经济运行的关键。本文以煤液化溶剂作用为基础,通过对液化自身产物、废塑料及FCC油浆等煤直接液化溶剂的组成、性质及作用效果的综合评述,指出煤、溶剂、氢气间的混合并非理想混合,与煤H/C适宜、极性相近的溶剂在共处理过程表现出良好的协同作用,液化过程的转化率、轻质产物选择性明显提高。分析表明,协同作用的大小取决于煤、溶剂的组成、性质匹配。煤-重质烃共处理工艺利用富芳烃油浆溶解性好、提供/传递氢能力强的特点强化了煤热解加氢反应的进行,同时煤加氢液化产生的多孔残煤具有吸附性强的特点,有助于重质烃改质,使共处理转化率显著提高、轻质产物选择性增大。最后指出,煤-重质烃共处理的协同作用为改善煤、中质/重质芳烃的综合利用提供了可能。     

民用工业中复合材料桁架的应用和发展

本文叙述了复合材料桁架的构造、分类和计算方法,突出了复合材料桁架的优越性能和在民用工业中的应用前景;在分析大量文献资料的基础上阐述复合材料桁架杆件的多种加工工艺,并比较不同截面形式对杆件性能的影响;探讨复合材料杆件的破坏机理和分析方法,介绍节点的类型和各自的特点,提出节点及连接部位存在的关键问题;根据国内外复合材料桁架的研究和应用现状,阐述了复合材料桁架的性能和不同的设计方法,总结归纳影响复合材料桁架性能的关键因素和设计中存在的一些问题,并提出改进杆件设计、节点设计和优化复合材料桁架的建议。     

从化学组成上区分宋代汝瓷与民窑钧瓷

应用质子激发Ｘ荧光分析技术测定了一组宋代汝瓷和一组宋代民窑钧瓷瓷片的化学组成及浓度，对汝瓷与民窑钧瓷的主量，次量化学组成和痕量化学组成进行了比较，应用模式识别方法加以研究，得到了区分宋代汝瓷和民窑钧瓷的可视分类图和数学判据。     

Barriers and facilitators to increase consumption of fruits and vegetables in six countries in Latin America

Low intake of fruits and vegetables is among the risk factors for cardiovascular disease and some cancers. The countries have implemented policies to promote food consumption. Identifying the barriers perceived by people to consume it helps to recognize the resources that would be willing to exchange for benefits. The objectives of this study are to determine what factors are facilitators and barriers to increasing consumption of fruits and vegetables in six countries in Latin America, and a possible relationship between the 5 a day program and the food based dietary guidelines. This is a qualitative and field study. Techniques used were group interviews with health professionals and the media, and interviews with experts in food policy. The outstanding facilitators were television advertising campaigns promoting their use, and the existence of fruits and vegetables markets in the neighborhoods. Highlighted those obstacles were lack of public policies of advertising regulations and trade hooks of food, of self-sustainability, of funding for related programs, and of sociological research of the topic. The main barrier to the consumption of fruits and vegetables in these countries was the lack of policy support and related public policy, being a good advertising campaign vital to the success of programs that encourage consumption. The main relationship between the Dietary Guidelines and the 5 A Day Program is to both promote the consumption of vegetables and fruits.     

Physicochemical Nature and Structural Dependence of the Unique Properties of Polyester Fibres

The structure and properties of PET and PET fibres are examined on three structural levels — molecular, supermolecular, and micromolecular. It was shown that the unique properties of the fibres are determined by the aliphatic-aromatic structure of PET and the chemically regular molecular structure. The structural dependence of the fundamental physicomechanical and physicochemical properties of PET and PET fibres was analyzed. It was shown that the high glass transition temperature of PET and PET fibres is determined more by molecular rigidity than by intermolecular interactions and varies little under the effect of moisture. This causes high stability of the structure in mechanical effects and exposure to heat and moisture, high reversibility of deformation, and insignificant creep under mechanical stresses. The structure and fundamental properties of PET and PET fibres are compared with the characteristics of other kinds of large-tonnage fibre-forming polymers and fibres and other aliphatic-aromatic polyesters and fibres. The advantages of using polyester fibres for fabrication of household and industrial articles are substantiated and summarized based on an examination of the properties of these fibres.     

武器信息化条件下火炸药发展策略分析

分析了火炸药与武器信息化的关联性;论述了火炸药在武器装备发展中的综合地位与作用;提出作为武器信息化条件下火炸药发展策略和基本点的六项技术,即火炸药相关信息量的整合与准确表达、高能量与高安全性的统一、能量释放的可控制性、洁净燃烧与爆炸技术、燃烧爆炸的物理与化学作用延伸、非致命武器与化学战剂等.     

Heterogeneity in fecundability studies: issues and modelling

Modelization of fecundability stepped recently from demography and population-based contexts to reproductive biology and treatment of infertility. This created a strong call for flexibility and robustness. Indeed, explained and unexplained heterogeneities are non-negligible sources of bias that result in false conclusions as to the determinants of fertility or to the success rates of reproductive techniques, among other examples. There are two main sources of heterogeneity: biological heterogeneity and heterogeneity of sexual behaviour. A uniform presentation of time-to-pregnancy and Barrett-Marshall models is proposed to enlighten their similarities and differences in modelling heterogeneity of fecundability. Mixed models for fecundability studies are presented as tools to allow for unexplained heterogeneity and to quantify heterogeneity of the effect of observed factors and variability of size of this unexplained heterogeneity between subpopulations. Some criteria for the modelling strategy in fecundability studies are suggested with emphasis on the unit-treatment additivity criterion. The strong and complex selection process resulting from heterogeneity is described as well as the selection and cross-selection processes of observed and unobserved fecundability factors. Consequences regarding data collection and statistical inference are discussed. In the current context, a consensus setting general rules for data collection and statistical analysis would be useful to compare the results and increase the reliability of these results in medical practice.