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1.
The oxidation/sulphidation behaviour of a Ti‐46.7Al‐1.9W‐0.5Si alloy with a TiAl3 diffusion coating was studied in an environment of H2/H2S/H2O at 850oC. The kinetic results demonstrate that the TiAl3 coating significantly increased the high temperature corrosion resistance of Ti‐46.7Al‐1.9W‐0.5Si. The SEM, EDX, XRD and TEM analysis reveals that the formation of an Al2O3 scale on the surface of the TiAl3‐coated sample was responsible for the enhancement of the corroison resistance. The Ti‐46.7Al‐1.9W‐0.5Si alloy was also modified by Nb ion implantation. The Nb ion implanted and as received sampels were subjected to cyclic oxidation in an open air at 800oC. The Nb ion implantation not only increased the oxidation resistance but also substantially improved the adhesion of scale to the substrate.  相似文献   
2.
A review of Distributed Infrastructure Support for Electronic Commerce Applications by Hans-Arno Jacobsen.  相似文献   
3.
Samples of {4-(dimethylamino) stilben Z & E 4'-yl} dimesityl borane (BNS) were synthesised and investigated for their non-linear optical properties. The results show that the quadratic hyperpolarisability of the Z-isomer is smaller than that of the E-isomer, the beta value found for the latter being as high as 60 × 10?30 esu.  相似文献   
4.
DriedMusa paradiciaca (banana) stem and veins of the leaves, which were hitherto discarded as a waste, were collected and used as starting material for the preparation of cellulose and cellulose acetate. This cellulose acetate was mixed with polystyrene to form blend of cellulose acetate-polystyrene in order to provide enhanced stability and extended utility to the end products. The films of these composites or their individual partners were made separately and studied for their mechanical properties, chemical modification and morphological changes. We report here that banana stem is good source of cellulose and that cellulose completely undergoes modification upon esterification.  相似文献   
5.
Intact and ovariectomized oxytocin (OT)-deficient (OT-/-) and wild-type (OT+/+) mice were tested for consumption of 0.5 M NaCl solution or tap water in a 2-bottle choice test. During 3 days of acclimation, voluntary ingestion of NaCl was equal between genotypes. After overnight fluid deprivation, intact OT-/- mice ingested 2 times more NaCl solution than OT+/+ mice in the 6th hr, but not the 1 st hr, after reintroduction of fluid. Ovariectomized mice consumed less than intact mice after overnight fluid deprivation. When a 0.2 M NaCl solution was administered for 6 days in ovariectomized mice, OT-/- mice voluntarily consumed greater amounts than OT+/+ mice. After overnight fluid deprivation, consumption by OT-/- mice was 3 times that of OT+/+ mice at 1 hr and 2-fold greater after 6 hr. Enhanced intake of NaCl-containing solutions in female OT-/- mice suggests that central OT may be an important inhibitor of sodium consumption. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Patterns of smoking cessation using 6- and 12-mo follow-up data are reported for 1,261 primary care patients randomized to 3 physician-delivered smoking interventions: advice only (AO), counseling (CI), and counseling plus availability of nicotine-containing gum (CI?+?NCG). One-week point-prevalence cessation rates at 12 mo did not differ among the interventions: AO (15.2%), CI (12.9%) and CI?+?NCG (16.7%). However, maintained cessation rates (abstinent at both 6 and 12 mo) increased with intervention intensity: AO (6.0%), CI (7.8%), and CI?+?NCG (10.0%): Test of trend χ–2?=?5.06, p?=?.02. CI?+?NCG was significantly higher than AO (p?=?.02). The findings support the following conclusions: Brief physician delivered intervention with availability of nicotine-containing gum can have a beneficial long-term effect on smoking cessation, and cohort data as well as point-prevalence rates are important when assessing the long-term impact of lifestyle interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We conducted a retrospective study of 516 cardiac recipients who underwent transplantation between April 1983 and April 1992, 19 of whom had development of post-transplantation lymphoproliferative disorders (PTLDs). These 19 patients presented with involvement of lung (5), gastrointestinal tract (5), disseminated disease (6), and adenoids and lymph nodes (3). B-cell proliferations ranging from an atypical hyperplasia to malignant lymphoma developed in 18 patients, and mixed cellularity Hodgkin's disease developed in 1 patient. The 19 patients with PTLD displayed a predominance of both women and cardiomyopathy as the indication for transplantation when compared with two separate control populations. No correlation was found between demographic criteria analyzed and (1) early versus late diagnosis of PTLD after transplantation, (2) the site of PTLD involvement, or (3) the histopathologic category of the PTLD lesion. Patients with gastrointestinal tract and lung PTLD involvement enjoyed an improved survival after both transplantation and PTLD diagnosis when compared with patients with PTLD involvement of all other extranodal sites. We report a high incidence of PTLD involving the lung and gastrointestinal tract in our cohort study. These sites of involvement responded better to a reduction in immunosuppression than did the other extranodal sites of involvement.  相似文献   
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