Toxikologische Prüfung eines Geschirrspülmittels

Toxicological Examination of a Dish-Washing Agent The acute toxicity, emetic action and tolerance of a commercial dish-washing agent were investigated in mice, rats and dogs, whereby the animals were subjected to repeated ingestion of this substance. Furthermore, the toxic actions on embryo and the effect on fertility were tested. The preparation showed a very low acute toxicity and it caused nausea in dogs given moderate doses. Repeated intake of high doses was tolerated by rats. No signs of intolerance were shown by dogs which received subemetic doses. No effect of the preparation on fertility and embryo-development could be detected. It can be concluded from these results that the application of the preparation as dish-washing agent does not involve any risk to the health.     

透明防污涂料的研制

研制出一种透明防污涂料用树脂和一种透明防污涂料,通过浅海浸泡试验、现场试验对防污性能进行了评价。结果表明:该透明涂料对海洋环境友好,不影响透光性;施工方便,可涂装于特殊底材表面。     

Solid-state structure of melt blended incompatible polymeric mixtures involving poly(vinyl chloride)

Poly(vinyl chlorides) having different melt viscosities were melt blended with several different incompatible polymers using a two-roll mill and a Brabender Plasticorder. The properties of the mixtures can be easily reproduced from batch to batch only if the viscosity of the components does not change during the mixing process. Within this limitation, the order of addition of the components during the mixture preparation does not have a significant influence on the mixture properties. The shear storage modulus of the incompatible mixtures in the temperature range between the Tg's of the components varies with the difference in component viscosities at the temperature of mixing. The moduli of these mixtures are compared to moduli calculated using Kerner's equations. Based on this comparison it is concluded that in any incompatible mixture the component having the lower melt viscosity at the temperature of processing tends to form a continuous phase in the mixture. The greater is the viscosity difference, the greater is this tendency. The viscosity of one component relative to the other can be changed by changing the molecular weight of the components and/or the temperature of mixing.     

Coating of carbon-fiber surface by silicon carbide via sol-gel mixtures of tetraethyl orthosilicate and phenolic resin

The preparation of a SiC coating on a carbon fiber surface using a sol-gel mixture of tetraethyl orthosilicat (TEOS) and phenolic resin was studied. FTIR and SEM investigations indicated that the SiC coating can be formed by carbothermal reduction of the sol-gel mixture at 1420°C for 15–20 min in an argon atmosphere. TGA of the coated fiber was also performed, showing that the SiC coating improves the thermooxidative stability of the carbon fiber. With the thickness of the obtained coating of 0.47 μm using a C/Si ratio of 4, this treatment does not affect the carbon fiber strength.     

Molecular design of supported niobium oxide catalysts

The current investigation demonstrates that it is possible to molecularly design supported niobium oxide catalysts with the assistance of molecular characterization methods such as Raman spectroscopy. The formation and location of the surface niobium oxide species are controlled by the surface hydroxyl chemistry, and the surface niobium oxide species are located in the outermost layer of the catalysts as an overlayer. The catalyst composition is a critical parameter since it affects the presence of different niobium oxide species (several different surface species and crystalline phases), and the reactivity also varies somewhat with surface niobium oxide coverage. The preparation method is not a critical parameter since it does not appear to influence the structure or reactivity of the surface niobium oxide species. However, for silica supported niobium oxide catalysts the preparation method does affect the amount of niobium oxide that can be dispersed as a two-dimensional overlayer. Calcination temperature is an important parameter that controls the activation and deactivation of the supported niobium oxide catalysts, but calcination temperature is not critical if moderate temperatures, 400–500°C, are used. The specific oxide support is a critical parameter since it dramatically affects the reactivity of the surface niobium oxide species and determines if the surface niobium oxide site is active for redox or acid catalysis. Thus, the critical parameters that affect the catalytic properties of the supported niobium oxide catalysts are the specific oxide support and catalyst composition.     

Effect of Hot Pressing on the Performance of Direct Methanol Fuel Cells

The effects of hot pressing of electrodes onto Nafion^® membranes in the preparation of membrane and electrode assemblies for direct methanol fuel cells have been investigated. Hot pressing does not significantly influence the cell resistance or methanol crossover, but it can decrease cell performance by restricting mass transport in the anode catalyst layer. It also increases the time required for the cell to reach optimum performance. Best performances were obtained with membrane and electrode assemblies that had not been pressed. It was also found that membranes that had not been subjected to hot pressing could easily be re-used, making recycling of membranes and catalysts more feasible.     

A facile synthesis method of nickel nanotubes assisted by polyethylene glycol

Using an easy and general way, magnetic metal nickel nanotubes are successfully fabricated by adding polyethylene glycol (PEG200, PEG2000, and PEG20000) in the common electrolyte solution combined with electrodeposition technique. This method is very easy, effective, and facile. Especially, the pore wall of the template need not be modified, and their wall thickness can be effectively controlled by adjusting the experimental parameters, such as the electric current density, the concentration of polyethylene glycol, and the electrodeposition time. The possible formation mechanism is proposed. The magnetic measurement of Ni nanotubes indicates that the difference of the polymers used in the preparation does not have a notable effect on their magnetic properties. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers     

Preparation of high molecular weight monodisperse polystyrene latexes by concentrated emulsion polymerization

The preparation of high molecular weight monodisperse polystyrene (PS) latexes by the concentrated emulsion polymerization is investigated. The PS latexes thus obtained have diameters in the range of 0.1–0.3 μm. The average size and the dispersity of the latexes are dependent on the concentration of surfactant (SDS), the monomer volume fraction, and the amount of monpolymerizable additive (decane). The ionic strength does not seem to affect the size but affect the dispersity of the latexes. Under proper conditions, monodisperse particles can be prepared with a quite small standard deviation. © 1993 John Wiley & Sons, Inc.     

含竹叶黄酮化妆品的研制

竹叶提取物是中国新开发的一种植物类黄酮制剂,具有优良的抗自由基、抗氧化、抗衰老、抗菌、抗病毒及保护心脑血管,能清除人体内活性氧化自由基防止生物膜脂质被超氧自由基和羟基自由基氧化,而且不含任何有害成分和抗营养因子,对人体无毒、副作用,具有极大的安全性,结构稳定,不易被降解。竹叶黄酮可用于清洁皮肤,帮助抗老化,是天然的抗氧化剂,可作为新型护肤因子,添加至美白、祛斑、抗皱等高端护肤品中,具有极大的市场潜力。对提取竹叶黄酮常用的三种方法：冷浸提取法、索氏提取法和超声波提取法各自的特点进行了分析;对分离纯化的四种方法进行实验,并以芦丁作为标样,绘制工作曲线方程,测定竹叶黄酮含量。其中,采用索氏提取法提取率达1．08％。制备了含有竹叶黄酮的无纺布面膜和凝胶面膜,经使用比较发现,无纺布面膜使用后美白、抗衰老的效果比凝胶面膜好,具有一定的市场应用价值。     

Conditions of utilization of coal mining and processing sludges as slurry fuel

The results of this study have shown that coal sludge can be used as slurry fuel (like coal-water fuel (CWF)) providing that its ash content does not exceed 30% and the amount in the fuel is at least 55%. The conventional CWF preparation technologies are inapplicable to the fabrication of water-sludge fuel; therefore, special technologies with allowance for the ash content, the particle size, and the water content of coal sludge are demanded.     

Modulators of Wnt Signaling Pathway Implied in Dentin Pulp Complex Engineering: A Literature Review

The main goal of vital pulp therapy (VPT) is to preserve the vitality of the pulp tissue, even when it is exposed due to bacterial invasion, iatrogenic mechanical preparation, or trauma. The type of new dentin formed as a result of VPT can differ in its cellular origin, its microstructure, and its barrier function. It is generally agreed that the new dentin produced by odontoblasts (reactionary dentin) has a tubular structure, while the dentin produced by pulp cells (reparative dentin) does not or has less. Thus, even VPT aims to maintain the vitality of the pulp. It does not regenerate the dentin pulp complex integrity. Therefore, many studies have sought to identify new therapeutic strategies to successfully regenerate the dentin pulp complex. Among them is a Wnt protein-based strategy based on the fact that Wnt proteins seem to be powerful stem cell factors that allow control of the self-renewal and proliferation of multiple adult stem cell populations, suitable for homeostasis maintenance, tissue healing, and regeneration promotion. Thus, this review outlines the different agents targeting the Wnt signaling that could be applied in a tooth environment, and could be a potential therapy for dentin pulp complex and bone regeneration.     

无中心支撑熟料库顶钢结构形式选型

熟料库顶钢结构主要有网架结构和实腹梁式结构。网架结构不需要临时钢支架,可以采用自承式安装,常用吊装机具即可完成,施工周期相对更短;实腹梁式结构需要提前准备库内临时钢支架,需要借助大型吊装机具才能进行安装,施工难度和安全风险也更高;以国内、外两个10 000 t储料库项目为例,从结构形式、施工方法、施工成本方面对比分析网架结构和实腹式钢梁结构的技术经济特点。     

A Reappraisal of Silver Fulminate as a detonant

The preparation and properties of silver fulminate have been examined to assess its potential for use as a primary explosive. It is an extremely effective detonant but does not appear promising as a stab-sensitive material. It is concluded that its extreme sensitiveness and the hazards and difficulties associated with its preparation render it unsuitable for military applications. It does find commercial use in the manufacture of toys and crackers when it is normally handled exclusively in small quantities and in the wet state.     

Experimental and statistical study of three adherence tests for an epoxy-amine/aluminum alloy system: Pull-Off,Single Lap Joint and Three-Point Bending tests

The mechanical resistance of a bonded joint depends on the adhesive interaction onto the substrate and the mechanical properties of the adhesive itself. Many existing tests can be useful for measuring the adherence or evaluating mechanical adhesive response. All these tests do not provide the same information: in particular, adherence measurements can be split into initiation tests and propagation ones. In this paper, three adherence tests have been considered for the evaluation of the fracture initiation between a poly-epoxide adhesive (a mixture of pure epoxy and amine) and an aluminum surface (AA 2024-T3), namely the Pull-Off, Single Lap Joint (SLJ) and Three-Point Bending tests. Various surface preparation protocols before bonding have been tested and optimized for aluminum substrates, including mechanical and chemical surface treatments, followed by the application of an appropriate primer before bonding. This study paves the way for the future development of adhesive systems as it provides reliable surface preparation protocols for aluminum surfaces and gives an insight into the choice of an adequate adherence test dedicated to high-performance adhesives. The load at break (F_Max), the experimental error, the failure mode and statistical studies according to the Weibull model and Principal Component Analysis (PCA) were studied on each surface preparation configuration. It has been shown that the application of a primer, especially a sol-gel product increases the load at break and provides more reliable results. Then, this paper shows that the two tests can quantify the failure initiation and distinguish the different surface preparation efficiency, are the Single Lap Joint test (mode II or mode I + II) and the Three-Point Bending test (mode I), with an increase of the results reliability with the latter one. The Pull-Off test (mode I) is useful as a routine checking, and particularly interesting because its response does not depend on the substrate thickness, even though it cannot highlight the difference between all surface preparations.     

Organic coatings for marginally prepared steel surfaces

The present study, carried out in the frame of a common research programme between the Institute of Chemistry, Faculty of Engineering at the University of Genoa and AGIP CORM Department about alternative surface preparation methods, is a preliminary contribution to the development of a series of rust-prevention coatings that can be applied directly in order to protect steel structures exposed to aggressive environments. The use of ‘rust converters’ may be considered a tool for alternative surface preparation but it is necessary to control the amount of loose rust layers and to ensure their complete removal. The poor adhesion level of converted layers is a problem not yet solved and it does not allow for a subsequent coating and/or finishing step. The application of the ‘surface tolerant’ coating systems seems to be a more useful way to protect steel structures without sandblasting and all its related economic and environmental disadvantages. The application of these systems on marginally prepared steel surfaces shows promising reliability both for the intrinsic protective power and for the adhesion to the metallic substrata. Their use during repainting maintenance is a reliable proposition and a profitable way to overcome not only technical problems but also subsequent environmental pollution and related constraints.     

A simple and fast method to disperse long single-walled carbon nanotubes introducing few defects

A simple and fast dispersion method that incorporates heating is used to disperse long (more than 10 μm) single-walled carbon nanotubes (SWCNTs) with minimal defects. The method enables a dispersed solution of SWCNTs to be produced in less than 10 min in only three steps: (1) addition of the dispersant, (2) heating, and (3) grinding. The dispersion method does not require sonication, which shortens the SWCNTs and can generate surface defects. SWCNT films were prepared from the dispersed solution, and the films exhibited a resistance of 380 Ω/sq at a transparency of 64.8%. This dispersion method can be easily scaled up, making it useful for the preparation of dispersed SWCNTs for commercial and industrial applications.     

KOH/ZrO2催化制备生物柴油新工艺

采用浸渍法,将KOH负载在新型载体氧化锆上,通过高温煅烧得到了固体碱催化剂。探讨了制备条件对催化剂催化酯交换反应活性的影响,获得了催化剂的最佳制备条件,以大豆油和甲醇为原料研究并优化了催化酯交换反应制备生物柴油的工艺条件。结果表明,固体碱催化剂KOH/ZrO₂的最佳制备条件为：KOH负载量20%,煅烧温度600℃,煅烧时间2 h。固体碱催化剂催化酯交换反应的最优反应条件为：醇油比9：1,反应温度75℃,反应时间3 h,催化剂用量4.0%。各因素对产率影响的大小为：醇油摩尔比 > 反应温度 > 反应时间 > 催化剂用量。     

Extraction of shape information from particle size measurements

Abstract

It is shown how a quantitative interpretation of the well known difference of particle size measurements (sedimentation and low angle laser light scattering) can be used to yield information on particle shape. Three kaolin types with different granulometry and composition were investigated. The concept of a median shape factor is introduced and a simple approximative equation is given to calculate it from results of routine size measurements. This median shape factor may be advantageously used as an index for the routine characterisation of powders with anisometric particles. For the kaolins investigated the value of the shape factor is shown to correlate well with the content of (more isometric) quartz grains. In contrast to the statistical method of shape determination by optical image analysis the ensemble method proposed here is less time consuming, does not require sophisticated sample preparation or specialised operators, and can be easily automated.     

低烟低毒天然橡胶用半聚脲阻燃涂料的制备与性能研究

介绍了天然橡胶用低烟低毒半聚脲阻燃涂料的原材料、基本配方、制备工艺和施工方法,其特点是涂料具有和基材相近的弹性和良好的附着力,所研制的涂料附着力1级,防腐蚀性能优异,氧指数大于30,烟密度小于200,烟毒性小于0．035,涂层可涂覆天然橡胶器件,不影响器件的减隔振效果同时起到一定的阻燃效果,在轨道交通等领域具有较好的应用前景     

Cellulosates of group ia metals—their preparation and reactivity with β-chloroethyldiethylamine

Mercerized cotton printcloth converted to a cellulosate of lithium, sodium, potassium, rubidium, or cesium by reaction with metal methoxide is a good substrate for the preparation of diethylaminoethyl (DEAE) cotton at low temperatures in nonaqueous media. The pretreatment to form the cellulosate of the alkali metal does not adversely affect mechanical properties of the cotton fabric. There is no advantage to using a cellulosate other than sodium cellulosate in reactions with β-chloroethyldiethylamine to form DEAE cotton. The reaction occurs in organic solvents of low and high dielectric constants. The hydrochloride of the amine rather than the free amine can be used to prepare DEAE cotton, provided the ratio of reactants is within specific limits. Consideration has been given to the mechanism of the reaction.