Biological and nutritional role of taurine and its derivatives on cellular and organic physiology]

Several aspects about the biological role of taurine and its derivatives has been described in this work, especially in relation to humans. Some aspects related to the structure and function of the molecule in respect to its capacity as an osmoregulator and as an antioxidant are also analyzed. Moreover, the distribution changes on the biosynthesis phenomenon in some development stages as well as changes at the transport level, especially in some tissues where the concentration is increased several times with respect to plasmatic concentrations, are discussed. Some evidences exist as to the possibilities that taurine may be considered as a conditionally essential nutrient, particularly in some cases where it has been demonstrated that taurine and its derivatives have certain clinical and nutritional implications.     

羟基和氨基苯类化合物的生物氧化与代谢

引言 芳香类污染物是自然界分布广泛的一类化合物,主要来源于石油工业、造纸业、塑料加工、纤维制造以及农药生产等[1].其中大多数酚(羟基苯)和芳香胺(氨基苯)具有很强的毒性和致癌性,因此被很多国家列为首要污染物[2-3].由于物理处理法和化学处理法成本高且可能引入其他有害物质[4],人们日益关注成本低廉而处理彻底的生物法[3].     

Medium chain length fatty acid esters and their medical and nutritional applications

Caprylic and capric acid esters and their applications in medical, nutritional and dietetic uses are described. Medium chain triglycer-ides (MCT) as a tool in the control of obesity, control in the choles-terol deposition in the tissues as well as a means of lowering serum cholesterol are cited as unique characteristics of such lipids. MCT as a source of quick energy and high energy is suggested as an alterna-tive to the conventional fats and oils (LCT). Dietetic and nutritional application utilizing the unique characteristics of caprylic and capric acid esters is indicated as alternatives to conventional fats and oils. The mono-diglycerides of caprylic and capric acid as cholesterol dis-solving agents in treating of patients having cholesterol gallstones is described to illustrate the unique solvency properties of such mono esters in medical applications. The possibility of such mono esters of di- and polyhydric alcohols to act as co-solvents for oil and water systems is suggested which can be applied in medical, pharmaceuti-cal and allied fields. Structured lipids with a predominance of capry-lic and capric acid to modify the properties of triglycerides is described for hyperalimentation uses as well as the special nutri-tional and dietetic needs.     

耐热耐迁移绿色环保聚酯增塑剂的合成及其对PVC增塑性能的研究

以1,4环己烷二甲醇、戊二酸和2丙基庚醇为原料,采用酯化缩聚法,以钛酸四正丁酯为催化剂、环己烷为带水剂,合成了新型的聚戊二酸1,4环己烷二甲醇酯增塑剂。目标分子结构中含有六元脂环、线性碳链及酯基的多官能团组成,通过傅里叶变换红外光谱仪、核磁共振谱仪和高效液相色谱仪等对聚酯的结构、相对分子质量进行表征。结果表明,制备的聚酯作为增塑剂混合到聚氯乙烯（PVC）中,PVC/聚酯复合材料的断裂伸长率为677.15 %,而PVC/邻苯二甲酸二辛酯（DOP）复合材料的断裂伸长率在相同测试条件下为693.82 %,聚酯与DOP在加入到PVC中的拉伸性能相差不大,但是,PVC/聚酯复合材料耐热性相对于PVC/DOP复合材料来说提高了158 ℃,并且在活性炭中的迁移性降低了16 %;PVC/聚酯复合材料相对于PVC/DOP具有较好的耐热性和耐迁移性。     

Ash properties and environmental impact of various biomass and coal fuels and their blends

Aiming at investigating the influence of minerals in co-firing applications in existing and developing systems, as well as their environmental impact upon recycling to soils, we used a combination of techniques such as X-ray fluorescence spectroscopy, ultraviolet and visible spectroscopy, inductive coupled plasma spectroscopy, X-ray diffractometry, differential thermal analysis and fusibility analysis to characterize various biomass and coal ashes and their blends, with biomass proportions up to 20%. Slagging and fouling propensities were predicted.The results showed that biomass ashes were richer in calcium, silicon and alkali minerals and micronutrients such as Zn, Cu and Mn, in comparison to coal ashes. Some could be useful for soil amendment or the cement industry. Slagging/fouling problems should be expected in boilers operating above 1000 °C, especially those firing cotton residue, vine shoots and bituminous coal without pre-treatment. However, the environmental impact of either biomass or coal ashes upon their disposal is expected to be very low, as leaching tests have shown. For coal/biomass blends, the composition and the fusibility of the ashes varied between those of the individual components. Thus co-firing processes using the alternative fuels studied up to 20% would not entail significant limitations in the system operation or the management strategies of ashes.     

Nanobioelectrocatalysis and Its Applications in Biosensors, Biofuel Cells and Bioprocessing

This review details the use of nanomaterials to improve bioelectrocatalysis for biosensor and biological fuel cell applications. Different types of bioelectrocatalysts are described as well as different types of nanomaterials for improving the rate of bioelectrocatalysis, as well as the active surface area of the electrodes.     

Osmo-Convective Drying of Fruits and Vegetables: Technology and Application

With reference to typical food preservation processes which consist of changing the water binding to material, the technology and application of osmotic dehydration were discussed as an initial treatment before convection drying of fruit and vegetables. Particular attention was paid to the possibilities to produce more shelf-stable food while keeping the high quality of final product. The course of osmotic dehydration of plant tissue as well as its influence on convection drying and on the properties of preserved fruit and vegetables were presented.     

Complexity, bifurcation and chaos in natural and man-made lumped and distributed systems

Complexity is a very diversified and branched subject and, ironically, is itself quite complex. In this paper, although we present the different aspects and definitions of complexity, we concentrate on its chemical/biological engineering relevance, especially for reaction/diffusion and hydrodynamic processes. System theory is used as the common language to unify concepts, and emphasis is given to bifurcation, chaos as the basis of behavioral complexity and the configuration of processes as the basis for structural complexity. Natural processes are grouped under biocomplexity, while man-made processes are treated as complexity alone. We restrict our attention in this paper to systems that do not change their structure during the process, so that self-organizational criticality is explained, but not utilized. Computational complexity is intrinsically inherent in all the processes we consider, but it is not given much attention in this paper. Despite these severe limitations on the scope of our paper, the subject is still quite complex and branched, and this paper tries to bring it to the attention and interest of a wider spectrum of chemical/biological engineers in both academia and industry.     

Cobalt on and in zeolites and silica–alumina: Spectroscopic characterization and reactivity

The adsorption of CO at 130 K has been studied on Co-H-FER, Co-H-MFI and Co-H-MOR, as well as on Co-silica–alumina and on Co-containing mesoporous materials. Over Co-H-MFI also the adsorption of NO and of ammonia and the coadsorption of ortho-toluonitrile and CO have been investigated. The data show that on all samples Lewis acidic isolated Co²⁺ species are predominant. However, small amounts of oxidizing sites, possibly Co³⁺ and/or cobalt oxide particles also exist. This is shown by the oxidation of part of CO to CO₂ and of NO to NO⁺ at very low temperature as well as by the formation of Co³⁺ mononitrosyls upon adsorption of NO. These sites, although difficult to be evidenced by direct spectroscopic measurements, are likley the active sites for CH₄-SCR, where NO is activated as an adsorbed N_xO_y species able to react selectively with methane.     

纳米微粒作为润滑油脂添加剂的现状与发展趋势

通过对目前润滑油脂添加剂研究成果的综合分析,提出了当前研究中存在的一些问题以及今后应关注的研究方向,特别强调应重点加强特殊环境,如高温、重载、磨损表面的修复、环境友好等条件下的纳米润滑添加剂的研制,纳米微粒润滑机理与其特殊的摩擦学性能之间的关系,以及表面修饰纳米微粒的工业化研究。     

产磷脂酶菌株的筛选鉴定及其应用

采用磷脂平板初筛和摇瓶复筛,从富油土样中筛选得到一株产磷脂酶菌株BIT-18。经菌株形态特征、生理生化特征及16S rRNA序列分析,鉴定其为荧光假单胞菌（Pseudomonas fluorescens）。以磷脂标准品（1-棕榈酰-2-油酰-Sn-甘油-3-磷脂酰胆碱）为底物,通过气相色谱分析反应产物的脂肪酸成分,定性鉴定P.fluorescens BIT-18表达的磷脂酶为B型磷脂酶。该酶为低温酶,最适温度和pH值分别为25℃和6.5,低浓度的金属离子有利于其酶促反应进行。以磷脂酶B为催化剂在自制间歇式反应器中对大豆油进行酶法脱胶,在加酶量500 U·kg^-1,加水量2%,温度40℃,pH 4.7的条件下反应6 h,脱胶油磷含量由90.1 mg·kg^-1降至4.6 mg·kg^-1,脱胶率高达94.9%,显示出良好的应用前景。     

Glyco-functionalised quantum dots and their progress in cancer diagnosis and treatment

Despite all major breakthroughs in recent years of research, we are still unsuccessful to effectively diagnose and treat cancer that has express and metastasizes. Thus, the development of a novel approach for cancer detection and treatment is crucial. Recent progress in Glyconanotechnology has allowed the use of glycans and lectins as bio-functional molecules for many biological and biomedical applications. With the known advantages of quantum dots (QDs) and versatility of carbohydrates and lectins, Glyco-functionalised QD is a new prospect in constructing biomedical imaging platform for cancer behaviour study as well as treatment. In this review, we aim to describe the current utilisation of Glyco-functionalised QDs as well as their future prospective to interpret and confront cancer.     

官能化乙丙橡胶的制备和表征

用２,５－二甲基－２,５－二叔丁基过氧基己烷为引发剂,甲基丙烯酸环氧丙酯（ＧＭＡ）、马来酸酐（ＭＡＨ）和丙烯酸（ＡＡ）为接枝单体,对三元乙丙橡胶（ＥＰＤＭ）和二元乙丙橡胶（ＥＰＲ）进行熔融接枝,接枝产物用ＦＴＩＲ、１３Ｃ－ＮＭＲ等进行了表征,并用化学滴定方法对接枝率进行了测定。实验结果表明,影响接枝率和凝胶质量分数的主要因素为乙丙橡胶的化学结构、引发剂和单体的用量、反应时间及温度等。接枝单体反应活性大小依次为ＧＭＡ,ＡＡ,ＭＡＨ。     

Power issues in the manufacturing and characterization of polymers and composite materials

Dynamic Mechanical Analysis (DMA), although utilized for more than three decades, has been restricted so far to material characterization rather than processing. Recently the importance of power for describing viscoelasticity in prepreg process operations has been demonstrated. This present work views DMA as an integral part of the power analysis of processes. In this study, four types of prepreg were produced under the same power of impregnation utilizing epoxy resins with various PEI contents. Prepregs were tested for compressive and toughness power as well as loss power. Laminates were developed and analyzed by DMA. DMA data was treated according to the established power methodology and compared with the tack power of the original prepreg. Specific compressive power was generally found to increase with increasing storage DMA power, while specific toughness power was found to show the opposite trend. The inverse of power, defined as tolerance, was also investigated. The out-of-phase DMA tolerance was found to correlate to loss prepreg power, bringing a deeper understanding to the fundamentals of viscoelasticity formation. This analytical methodology can be applied beneficially to many topics to provide a better understanding of polymers and composites, as well as smart materials.     

Processing,structure, and properties of gel spun PAN and PAN/CNT fibers and gel spun PAN based carbon fibers

Polyacrylonitrile (PAN) and PAN/carbon nanotube (PAN/CNT) fibers were manufactured through dry‐jet wet spinning and gel spinning. Fiber coagulation occurred in a solvent‐free or solvent/nonsolvent coagulation bath mixture with temperatures ranging from ?50 to 25°C. The effect of fiber processing conditions was studied to understand their effect on the as‐spun fiber cross‐sectional shape, as well as the as‐spun fiber morphology. Increased coagulation bath temperature and a higher concentration of solvent in the coagulation bath medium resulted in more circular fibers and smoother fiber surface. as‐spun fibers were then drawn to investigate the relationship between as‐spun fiber processing conditions and the drawn precursor fiber structure and mechanical properties. PAN precursor fiber tows were then stabilized and carbonized in a continuous process for the manufacture of PAN based carbon fibers. Carbon fibers with tensile strengths as high as 5.8 GPa and tensile modulus as high as 375 GPa were produced. The highest strength PAN based carbon fibers were manufactured from as‐spun fibers with an irregular cross‐sectional shape produced using a ?50°C methanol coagulation bath, and exhibited a 61% increase in carbon fiber tensile strength as compared to the carbon fibers manufactured with a circular cross‐section. POLYM. ENG. SCI., 55:2603–2614, 2015. © 2015 Society of Plastics Engineers     

废旧干电池的回收利用

本文介绍了废旧干电池可能给环境带来的危害，回收的意义，以及再生利用的途径，并提出了干电池回收中应注意的几个问题。     

Comparison of the anthropometric and biochemical variables between children and their parents

The objective of this study was to compare the anthropometry, body composition and biochemical profile between eutrophic and obese children, as well as to relate the children's nutritional state and body composition to those of their respective parents. A control-case study was carried out with 50 eutrophic and 50 obese children paired according to gender, age, socioeconomic condition, and selected from the nutritional evaluation of 2 074 children aged 6 to 8 years, attending public and private urban schools in Vi?osa, Minas Gerais, Brazil. The measurements evaluated were weight, height, circumferences (waist and hip) and thickness skinfolds (triceps and subscapular). The serum levels of glucose, total-cholesterol, HDL, LDL, triglycerides and hemoglobin in the children were evaluated. The obese children presented a larger body size and higher percentage for total body fat as well as its accumulation in the central region, and higher serum levels for triglycerides (p < 0.05). For all biochemical parameters, except for hemoglobin and HDL, there occurred a positive correlation with the located fat in the central region as well as with the total body fat in children (p < 0.05). The obese mothers showing high percentage of body fat and its accumulation in the central region rather tend to have children with these characteristics (p < 0.05). The highest number of the close relatives who are obese and present dyslipidemia is highlighted in the obese children (p < 0.05). This study evidences the differences concerning to the distribution of the body fat and lipid profile among eutrophic and obese children, as well as the strong influence of the maternal obesity upon child's obesity.     

Nickel and Fischer-Tropsch Synthesis

Nickel has been reviewed as a catalyst and promoter in the Fischer-Tropsch synthesis (FTS). The main obstacle to its industrial application is the formation of volatile carbonyls, causing deactivation and loss of active phase, as well as a somewhat lighter product than from Co or Fe catalysts. Presented are both experimental and theoretical work pointing to suitable techniques for catalyst preparation, its composition and activation, as well as operating conditions where Ni is capable of producing long chain hydrocarbons in the FTS. Some important perspectives are also provided based on thermodynamic calculations and suggestions for further work are included.     

混联式冷凝器的可视化及传热实验分析

在分析混联式冷凝器中强化凝结传热机理的基础上,选用相同尺寸的平行流冷凝器为基准对比样件,通过高速摄影可视化实验及冷凝器性能测试方法, 对分流孔径为2.5、4.5 mm的两种混联式冷凝器进行可视化分析表明,类似于蒸气喷射流的过热蒸气与气液两相流在集流管中强烈扰动混合,改善了进入下一冷却流道的两相流质量分布的均匀性,扩展了两相流传热区域在混联式冷凝器中的相对占有面积,这使其传热性能比平行流冷凝器可提高9.6%; 同时,制冷系统中的制冷剂质量流量则提高13.43%,为设计更紧凑的空调冷凝器提供了一种新的途径。     

镁及镁合金电镀与化学镀

介绍了镁及镁合金电镀与化学镀工艺流程、浸锌及直接化学镀镍等前处理工艺,以及已应用于镁及镁合金上的各种镀层.同时,对电镀及化学镀在镁及镁合金上的应用和发展状况作了简要评述.