The Effect of Composite Patches on the Failure of Adhesively-Bonded Joints Under Bending Moment

In this study, it was aimed to compare mechanical behavior of double-strap joints with aluminum (AA2024-T3) or 16-ply laminate of carbon/epoxy composite (T300/934) patches of different orientation angles at their overlap area subjected to bending moment. For this purpose, AA2024-T3 aluminum was used as adherend, while the adhesive was a two-part paste (DP 460). Six different types of joint samples were subjected to bending moment. The effect of patch material on failure load and stress distribution was examined experimentally and numerically. In the numerical analysis, the composite patches were assumed to behave linearly elastic, while adherend and adhesive layers were assumed to be nonlinear. It was found that the data obtained from 3-D finite element analysis were coherent with experimental results. Meanwhile, experiments showed that fiber orientation angles of the patches markedly affected the failure load of joints, failure mode and stress distributions appeared in adhesive and composite.     

Immobilization of albumin on magnetite nanoparticles

The magnetite (Fe₃O₄) nanoparticles were prepared by the co-precipitation of ferrous and ferric salts with NH₄OH, and then modified with 3-aminopropyltriethoxysilane (APTES) by silanization reaction and subsequent reaction with glutaraldehyde (GA) to obtain functional groups on their surface. The influence of different terminated groups on protein binding was studied with bare and modified magnetite nanoparticles. Amine terminated magnetite nanoparticles were shown the highest binding ability for immobilization process compared to Fe₃O₄ NPs and GA bonded NPs. This binding ability was shown by using sodium dodecyl polyacrylamide gel electrophoresis technique (SDS-PAGE). Albumin attached magnetite nanoparticles were also examined by Scanning Electron Microscopy (SEM).     

A SURVEY OF MICROBIOLOGICAL ASPECTS OF CIDER MAKING

Among the lactic microflora of ciders it was found that the species Leuconostoc oenos was predominant at the end of the alcoholic fermentation as well as at the end of the malo-lactic conversion. Among yeasts, the genera Saccharomyces was predominant at the end of fermentation. However, in the case of one juice characterised by a low initial level of bacteria, a high amount of phenolic compounds and a small quantity of total nitrogen, the whole lactic flora was no longer detected after a fortnight.     

High birefringence photonic crystal fiber with a complex unit cell of asymmetric elliptical air hole cladding

High birefringence induced by elliptical air hole photonic crystal fibers (EHPCFs) is analyzed numerically using the finite-element method. Statistical correlations between the birefringence and the various parameters are obtained. We found that the complex elliptical air hole is better than that of a circular one to obtain high birefringence in photonic crystal fibers. Our suggested structures can considerably enhance the birefringence in EHPCFs and show that the birefringence can be as high as 1.1294 x 10(-2), which is higher than the birefringence obtained from conventional step-index fiber (5 x 10(-4)), circular air holes PCF (3.7 x 10(-3)), and elliptical hollow PCF (2.35 x 10(-3)).     

半导体长波长异质结构材料光压谱测试探讨

本文介绍了ＩｎＰ、ＩｎＧａＡｓ、ＩｎＧａＰ、ＩｎＧａＡｓＰ等的光压港（ＰＶＳ）。并把ＩｎＧａＡｓＰ（在特定组份下）的ＰＶＳ与ＦＦＴ—ＰＬ谱进行了比较；分析和讨论了ＰＶＳ测试的局限性和复杂性；指出了对多层异质结构材料，只有把器件结构、外延工艺、ＥＣＶ测试等结合起来，才可能正确地理解ＰＶＳ给出的测试结果。     

The kinetics of bioaccumulation of zinc, copper, lead and cadmium by oysters (Crassostrea iredalei and C. belcheri) under tropical field conditions

Cyanobacterial neurotoxins have been implicated in animal deaths resulting from drinking contaminated water. Anatoxin-a (AN) and homoanatoxin-a (HMAN) have previously been analysed using high-performance liquid chromatography (HPLC) with UV detection, but this procedure is insufficiently sensitive and is subject to interferences. A sensitive fluorimetric (FL) method for determining AN was recently developed using derivatisation with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) and this has been applied to the simultaneous determination of AN, HMAN and their epoxy and dihydro degradation products. Microscale syntheses were used to prepare the dihydro and epoxy derivatives from AN and HMAN. These compounds were produced in high yields, as confirmed by electrospray MS and HPLC-FL of their benzoxadiazole derivatives. All six NBD derivatives were readily separated using isocratic reversed-phase HPLC. The recoveries of these compounds from spiked water samples, using weak cation-exchange (WCX) solid-phase extraction (SPE), were 83.2-84.9% at concentrations of 10 micrograms/l. The R.S.D. values were 1.7-3.9% (n = 8) and the limits of detection were better than 10 ng/l for all six compounds, illustrating the high sensitivity of the method. This methodology was successfully applied to the analysis toxin degradation products in natural samples. Dihydroanatoxin-a (0.8 mg/g) was isolated from a benthic Oscillatoria bloom from Caragh Lake, Ireland, and was found to contain two isomers but their ratio was different from that found in the synthetic material.     

Ferrimagnetic resonance and low temperature transition in Ni- and Co-substituted powder magnetite

The effects of nickel and cobalt substitution on ferrimagnetic resonance in high-purity magnetite powder have been investigated. The low-temperature transition temperature and damping parameter, , are found to decrease with increasing solute additions. The linewidth, H, varies in proportion to the anisotropy field of the ferrites, narrowing with increasing nickel content but broadening with increasing cobalt content. Theg factor increases with the dopant concentration, passing through a maximum around room temperature. Decreasing the deviation from stoichiometry by appropriate annealing decreases the transition temperature shift but slightly increases H, g and .     

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哈伯特储量发现模型是以勘探历史为背景的统计学模型，该模型不仅考虑了以往的发现率，而且考虑了当前的发现率，估算的最终或剩余储量更为准确，可靠，应用此模型对川南Ｐ１最终地质储量估算结果表明，在这个区带天然气最终可探明数百亿立方米，目前还有近七分之一的剩余地质储量尚待发现。