Biocomposites Made from Short Abaca Fiber and Biodegradable Polyesters

Natural fiber‐reinforced biodegradable polyester composites were prepared from biodegradable polyesters and surface‐untreated or ‐treated abaca fibers (length ca. 5 mm) by melt mixing and subsequent injection molding. Poly(butylene succinate)(PBS), polyestercarbonate (PEC)/poly(lactic acid)(PLA) blend, and PLA were used as biodegradable polyesters. Esterifications using acetic anhydride and butyric anhydride, alkali treatment, and cyanoethylation were performed as surface treatments on the fiber. The flexural moduli of all the fiber‐reinforced composites increased with fiber content. The effect of the surface treatment on the flexural modulus of the fiber‐reinforced composites was not so pronounced. The flexural strength of PBS composites increased with fiber content, and esterification of the fiber by butyric anhydride gave the best result. For the PEC/PLA composites, flexural strength increased slightly with increased fiber content (0–20 wt.‐%) in the case of using untreated fiber, while it increased considerably in the case of using the fiber esterified by butyric anhydride. For the PLA composite, flexural strength did not increase with the fiber reinforcement. The result of soil‐burial tests showed that the composites using untreated fiber have a higher weight loss than both the neat resin and the composites made using acetylated fiber.

Flexural modulus of PBS composites as a function of fiber content.     

Magnetic properties of metal layer deposited by reduction of metal ions contained in polymer with applying magnetic field

Metal layer was deposited by the reduction of NiCl₂ and CoCl₂ in polyacrylonitrile film after applying an external magnetic field in directions parallel and perpendicular to the surface of the film; the magnetic properties of the metal-deposited film were investigated. When the parallel magnetic field was applied, the values of coercivity (H_c), remanent flux density (B_r) and maximum flux density (B_s) increased regardless of the composition of the metal ions, compared with the case without the application of the magnetic field. From the scanning electron micrographs and X-ray diffraction analyses, it was shown that the growth of crystalline orientation in the deposited metals was enhanced by applying a parallel magnetic field.     

Formation mechanism for hexagonal-structured self-assemblies of nanocrystalline titania templated by cetyltrimethylammonium bromide

Hexagonal-structured self-assemblies of nanocrystalline (anatase) titania templated by cetyltrimethylammonium bromide (C(16)H(33)N(CH(3))(3)Br; CTAB) (Hex-ncTiO(2)/CTAB Nanoskeleton) were formed after mixing of aqueous solutions containing CTAB spherical micelles and titanium oxysulfate acid hydrate (TiOSO(4).xH(2)SO(4).xH(2)O) as a titania precursor in the absence of any other additives. Formation mechanism of the Hex-ncTiO(2)/CTAB Nanoskeleton was examined in terms of the reaction temperature, titania precursor/CTAB mixing ratio, surfactant type, electrostatic interaction, micelle formation and molecular component. We found that crystal growth of crystalline (anatase) titania (polymorphic crystallization) was promoted with higher temperature and lower titania precursor content in aqueous solutions. In addition, we revealed that the crystalline (anatase) titania was formed in polycation, poly(allylamine hydrochloride ([CH(2)CH(CH(2)NH(2))HCl](n); PAH), and formamide (HCONH(2)) solutions. On the other hand, no titania formation was observed in anionic systems such as sodium dodecyl sulfate (CH(3)(CH(2))(11)OSO(3)Na; SDS) and poly(sodium 4-styrenesulfonate ([C(8)H(7)SO(3)Na](n); PSSS). This indicates that hydrolysis reaction of the titania precursor is initiated by not only cations but also nitrogen atoms in molecules and polymers. Hexagonally structure was formed in only cationic surfactant micellar solutions but not in polycation solutions and formamide.     

Purification and separation of carbon nanocapsules as a magnetic carrier for drug delivery systems

Nanoparticles of iron carbides wrapped in multilayered graphitic sheets (carbon nanocapsules) were synthesized by electric plasma discharge in an ultrasonic cavitation field in liquid ethanol. The as-prepared material contained carbon nanocapsules but also included impurities such as amorphous carbon, graphite balls and flakes. These impurities must be removed to allow the development of applications for the carbon nanocapsules and, it is necessary to develop a suitable purification method to obtain samples of monodispersed carbon nanocapsules. Two purification methods were used. The first used a hydrogen peroxide solution and acid etching to remove the amorphous carbon and iron particles. These impurities were easily oxidized and dissolved in the solution and the graphite layers of the carbon nanocapsules were not damaged. The second used magnetic separation using permanent magnets to remove the graphite balls and flakes. Here, centrifugation was applied to separate the purified carbon nanocapsules around 100–200 nm in size.     

Stabilization of flavylium dye by incorporation into the pore of protonated zeolites

Flavylium dye, a model compound of natural anthocyanin, has a defect that its color stability is very poor. We have complexed the flavylium dye with protonated zeolites and succeeded to enhance both the thermal and chemical stability of the dye. The aqueous dispersion of the flavylium/zeolite complex maintains its color even at 353 K or at pH 9, under which conditions the aqueous solution of the flavylium loses its color immediately. The stability is enhanced when the dye is incorporated into the pore of the zeolites, and a large stabilization effect is obtained by a tight adsorption with a narrow pore, as long as the dye is incorporated into the pore. Because of its enhanced color stability, the flavylium dye incorporated in the zeolite pore can be a candidate for an environmentally friendly coloring material.     

Enabling Electrocatalytic Fischer–Tropsch Synthesis from Carbon Dioxide Over Copper-based Electrodes

We report on the discovery that paraffins and olefins up to C₆ hydrocarbons can be obtained in CO₂ electroreduction at room temperature and atmospheric pressure by application of a commercially available Cu-electrode (Eurofysica), provided pretreatment by electropolishing is avoided. The product distribution follows the Schultz–Flory distribution and, depending on the applied potential, the chain growth probability (α) ranges from 0.23 to 0.31, values lower than those obtained in Fischer–Tropsch synthesis over heterogeneous Co- or Fe-based catalysts.     

Changes of an Outer β-NiAl and Inner α-Cr Coating on Ni–40 at% Cr Alloy during Oxidation at 1373K in Air

Formation mechanisms of a coating with a duplex layer, outer β-NiAl(Cr) and inner α-Cr(Ni) layer structure on a Ni–40.2 at% Cr alloy were proposed and change in the coating structure was investigated during high temperature oxidation. The Ni–40.2 at% Cr alloy was electro-plated with about 12μm Ni followed by a high Al activity pack cementation at 1073K to form a coated layer with an outer δ-Ni₂Al₃ and an inner layer containing Al more than 70at% which grew with an inward diffusion of Al. The coated Ni–40.2at% Cr alloy was oxidized at 1373K in air for up to 2592ks. It was found that at the initial stage of oxidation the as-coated layer structure changed to a two-layer, outer β-NiAl(Cr) and inner α-Cr(Ni), structure. Al contents in the α-Cr(Ni) layer was less than 0.3at%. With long term oxidation an intermediate γ-Ni(Cr, Al) layer formed between the outer and inner layers, whereas the inner α-Cr(Ni) layer became thinner and then disappeared after the 2592ks oxidation at 1373K. Coating processes and changes in the coating structure during high temperature oxidation were discussed based on diffusion and composition paths plotted on a Ni–Cr–Al phase diagram     

Computational cavitation flows at inception and light stages on an axial-flow pump blade and in a cage-guided control valve

Cavitation flows induced around an axial-flow pump blade and inside a high pressure cage-type valve are simu-lated by a two-dimensional unsteady Navier-Stokes analysis with the simplest treatment of bubble dynamics.Thefluid is assumed as a continuum of homogeneous dispersed mixture of water and vapor nuclei.The analysis isaimed to capture transient stages with high amplitude pressure change during the birth and collapse of the bubbleespecially at the stage of cavitation inception.By the pump blade analysis,in which the field pressure is moderate,cavitation number of the inception and locations of developed cavitation are found to agree with experimental re-suits in a wide flow range between high incidence and negative incidence.In the valve flow analysis,in which thewater pressure of 5MPa is reduced to 2MPa,pressure change responding to the bubble collapse between the vaporpressure lower than 1 KPa and the extreme pressure of higher than 10~4 KPa is captured through a stable computa-tion.Location of the inception bubble and pressure force to the valve plug is found agree well with the respectiveexperimental features.     

地理信息系统辅助划分储层流动单元

根据地理信息软件Super Map二次开发的控件,采用VB语言开发了预测储层流动单元平面分布的应用软件。该软件利用Super Map中的矢量数据集保存孔隙度、渗透率、砂体厚度等参数的等值线图,利用栅格数据集保存沉积微相分布图,利用开发的叠加分析模块快捷地综合分析用于划分流动单元的多项参数。该软件利用地理信息系统(GIS)软件强大的数据管理、空间分析和图形可视化功能,提高了储层流动单元划分的效率,增加了划分结果的真实性与客观性。利用该软件对涠洲油田沉积微相、孔隙度和渗透率进行了综合判别在此基础上,划分储层流动单元。对该软件只要修改判别标准和改变数据集内容,可以应用到其他油田。     

陆相含油气盆地沉积体系再思考:来自分支河流体系的启示

通过分析分支河流体系的基本特征,对分支河流体系在陆相含油气沉积盆地沉积体系研究和油气勘探中的意义进行分析和讨论。分支河流体系是指河流从某一顶点开始进入盆地并呈放射状展布的沉积体系,包括最大规模的巨型扇、中等规模的河流扇以及小规模的冲积扇。分支河流体系广泛发育在拉张、挤压、走滑和克拉通盆地中,占据了沉积盆地大部分地区;河道呈分支状分布,但不一定同时都在活动;河道规模向下游逐渐减小,泛滥平原和河道所占面积之比不断增加,沉积物粒度逐渐变细。分支河流体系的沉积模式与冲积扇模式外形相似,但内容相差很大。河流流域盆地梯度和流域面积与分支河流体系的表面坡降和面积具有正相关性。分支河流体系是随着现代地球信息技术发展而提出的,也是冲积扇沉积学、河流沉积学和陆相沉积体系研究不断深入的结果,是陆相盆地沉积学与现代计算机和地理信息技术融合发展的结果。分支河流体系的研究促进了扇状沉积体系分类描述的系统化,促进了沉积微相和沉积模式的多样化,促进了沉积过程响应解释的精细化,促进了源汇体系分析的定量化。分支河流体系启发了对陆相盆地沉积体系展布模式、陆相沉积体系中河流沉积作用、陆相盆地岩相古地理格局以及陆相盆地油气勘探...