CHARACTERIZATION OF Si_(1-x-y)Ge_xC_y FILMS GROWN BY ION IMPLANTATION AND SUBSEQUENT SOLID PHASE EPITAXY

Si1-x-yGexCy ternary alloy films were grown on monocrystalline silicon substrates by C ion implantation and subsequent solid phase epitaxy (SPE). Two-step anneal-ing technique was employed in the SPE. The structure and electrical properties of the alloy films were determined using Fourier transform infrared spectroscopy and van der Pauw Hall measurements, respectively. With the optimization of two-step anneal-ing technique for the implanted Si1-x-yGexCy layers, a certain amount of C atoms occupied substitutional sites and no SiC was formed.     

A critical evaluation of several alcohol screening instruments using the CIDI-SAM as a criterion measure

Four alcohol screening instruments (the AUDIT, CAGE, MAST, and Svanum's scale) were administered to a sample of 306 undergraduate students at a Midwestern university and were compared with regard to several test characteristics, using the alcohol section of the CIDI-SAM (DSM-IV version) as the criterion measure. The performance of these instruments was evaluated using two subsets of subjects: (1) students who currently met diagnostic criteria for alcohol dependence (n = 35); and (2) students who met diagnostic criteria for alcohol dependence in the past and/or at present (i.e., lifetime diagnosis; n = 50). The AUDIT performed significantly better than the other three instruments in identifying students who were currently alcohol dependent, providing a moderate degree of clinical utility with this group. The four instruments did not differ significantly in their ability to identify students with a lifetime diagnosis; each measure provided only a modest degree of clinical utility with this group.     

松潘-甘孜褶皱带的深部地壳构造特征及油气前景

四川松潘-甘孜褶皱带一直是地球科学家关注的一个焦点。近年来，石油地质学家也对它表现出了很大的兴趣。根据地震测深、重、磁、电等的探查，发现该褶皱带深部有一低速高导层，而对大火成岩省一峨眉玄武岩喷溢-地幔柱的认识深化均表明，四川松潘-甘孜褶皱带是可望获得油气勘探突破的靶区，重要的是断裂构造、圈闭、储集层的耦合与优化。     

Grafting modification of Kevlar fiber using horseradish peroxidase

Summary Horseradish peroxidase catalyzed grafting of acrylamide (AM) onto Kevlar fibers in mixed solvents of dioxane and water was studied. The factors affecting the grafting reaction, such as solvents composition, reaction time, temperature, pH of reaction media, concentration of acrylamide and hydrogen peroxide were examined. The modified fiber was characterized with IR, scanning electron microscopy (SEM), elemental analysis, XPS, contact angle measurement and the grafting yield. The O/C ratio and N/C ratio on the surface increased after treatment and the surface of the Kevlar fiber became rougher. The contact angle decreased from 80 to 45 after grafting, indicating the wettability of the fiber increased after modification. All the results suggested that AM have been grafted onto the Kevlar surface through HRP-mediated radical initiated grafting reaction. And the probably mechanism of HRP catalyzed grafting of AM onto Kevlar surface was proposed.     

Water resistance of bone-cements reinforced with bioceramics

The water absorption behavior of bone-cements of PMMA reinforced with 1.5 wt.%, 2.5 wt.%, and 3.5 wt.% silane-treated powders of hydroxyapatite (synthetic, or derived from bovine bones, or teeth enamel), β-tricalcium phosphate (TCP), bioactive glass (45S5), and zirconia, was investigated. The experimental results showed that addition of calcium phosphate in the polymeric matrix favors water absorption except in the case of enamel hydroxyapatite. Water uptake is also suppressed when 45S5-bioglass or zirconia is added. The solubility is not affected by addition of hydroxyapatite or 45S5-bioglass but it increases when β-TCP or zirconia is added. A superior behavior of bone-cements reinforced with bioglass-45S5 and enamel hydroxyapatite can be suggested.     

Preparation and adsorption behavior of a cellulose‐based,mixed‐mode adsorbent with a benzylamine ligand for expanded bed applications

A novel mixed‐mode expanded bed adsorbent with anion‐exchange properties was explored with benzylamine as the functional ligand. The cellulose composite matrix, densified with stainless steel powder, was prepared with the method of water‐in‐oil suspension thermal regeneration. High activation levels of the cellulose matrix were obtained with allyl bromide because of the relative inertness of the allyl group under the conditions of the activation reaction. After the formation of the bromohydrin with N‐bromosuccinimide and coupling with benzylamine, the activated matrix was derived to function as a mixed‐mode adsorbent containing both hydrophobic and ionic groups. The protein adsorption capacity was investigated with bovine serum albumin as a model protein. The results indicated that the prepared adsorbent could bind bovine serum albumin with a high adsorption capacity, and it showed salt tolerance. Effective desorption was achieved by a pH adjustment across the isoelectric point of the protein. The interactions between the cell and adsorbent were studied, and the bioadhesion was shielded by the adjustment of the salt concentration above 0.1M. Stable fluidization in the expanded bed was obtained even in a 2% (dry weight) yeast suspension. The direct capture of target proteins from a biomass‐containing feedstock without extra dilution steps could be expected with the mixed‐mode adsorbent prepared in this work, and this would be especially appropriate for expanded bed adsorption applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Thermoelastic evaluation of composite laminates using digital imaging processing

The study of the variation of the curvature of non-symmetric composite laminates with temperature provides a measure of the magnitude of the thermal stresses and the mechanical behavior of the material with temperature. In the present work, an experimental method based on the pioneer use of a digital camera and image processing method is proposed to perform such measurements. Taking advantage of the method and by comparing experimental and CLT, extended-CLT and FEM simulation results, an evaluation of the residual stresses is described and an approach providing more precise determination of the residual thermal stresses in non-symmetric laminates is proposed.     

Synthesis,structure and near-infrared (NIR) luminescence of three solvent-induced pseudo-polymorphic complexes from a bimetallic Zn–Nd Schiff-base molecular unit

Three solvent-induced pseudo-polymorphic bimetallic Zn–Nd complexes [ZnNdL(OAc)(NO₃)₂(DMF)] · solvate (solvate: MeCN (1), THF (2), EtOH (3); H₂L = N,N′-bis(3-methoxy-salicylidene)phenylene-1,2-diamine) were obtained, and their solid NIR luminescence related to the packing structure from the intermolecular π–π interactions was discussed.