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991.
992.
Several 35CrMo4 and 38MnV7 steels with different additions of Ti and V were manufactured by electroslag remelting. The influence of the alloying and microalloying elements on phase transformation at different cooling rates was studied and the continuous cooling transformation diagrams were plotted. In order to optimize the heat treatment and improve the mechanical properties, the range of cooling rates leading to a fully bainitic microstructure （without ferrite, pearlite and especially without martensite） was determined. Bainite and martensite transformation start temperatures （Bs, Ms） were also established and compared with the values predicted by empirical equations. The important role of precipitates （especially V carbonitride particles） on final microstructure and mechanical properties was assessed. 相似文献
993.
Csaderova L Martines E Seunarine K Gadegaard N Wilkinson CD Riehle MO 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(23):2755-2761
A biodegradable substrate with a regular array of nanopillars fabricated by electron-beam lithography and hot embossing is used to address the mechanisms of nanotopographical control of cell behavior. Two different cell lines cultured on the nanopillars show striking differences in cell coverage. These changes are topography- and cell-dependent, and are not mediated by air bubbles trapped on the nanopattern. For the first time, a strong cell-selective effect of the same nanotopography has been clearly demonstrated on a large area; while fibroblast proliferation is inhibited, endothelial cell spreading is visibly enhanced. The reduced fibroblast proliferation indicates that a reduction of available surface area induced by nanotopography might be the main factor affecting cell growth on nanopatterns. The results presented herein pave the way towards the development of permanent vascular replacements, where non-adhesive, inert, surfaces will induce rapid in situ endothelialization to reduce thrombosis and occlusion. 相似文献
994.
Joo Yeon Kim Chiara Ingrosso Vahid Fakhfouri Marinella Striccoli Angela Agostiano M. Lucia Curri Jurgen Brugger 《Small (Weinheim an der Bergstrasse, Germany)》2009,5(9):1051-1057
Inkjet technology is a compelling method for the flexible and cost‐effective printing of functional inks. We show that nanocomposite solutions based on polystyrene and differently sized core/shell‐type nanocrystals (NCs) formed by a CdSe core coated with a shell of ZnS (CdSe@ZnS) in a single solvent, chloroform, can be reliably dispensed into luminescent, multicolor pixel arrays. This study demonstrates the relevance of parameters like polymer concentration and nozzle diameter, highlighting how the optimal conditions to print NCs embedded in 5 wt% polystyrene nanocomposite are given by a 70‐µm‐diameter nozzle. The obtained structures show that the bright size‐dependent emission of the NCs in the nanocomposite is retained in the printed pixels. 相似文献
995.
996.
Grüter L González MT Huber R Calame M Schönenberger C 《Small (Weinheim an der Bergstrasse, Germany)》2005,1(11):1067-1070
997.
M Tumbarello E Tacconelli MB Lucia R Cauda L Ortona 《Canadian Metallurgical Quarterly》1996,90(9):531-537
This study is based on a retrospective logistic regression analysis of all human immunodeficiency virus (HIV)-infected patients with Staphylococcus aureus pneumonia (SAP) admitted to the Department of Infectious Diseases, Catholic University, Rome, Italy between January 1986 and December 1994. Nineteen patients with 24 episodes of SAP were enrolled in the study. A control group of 38 HIV-infected patients without pneumonia was included. The attack rate of SAP was 8.31/1000 HIV-related hospital admissions and the frequency, out of the total number of bacterial pneumonia observed in the study period, was 16% (24 of 154 patients). The large majority of SAP was community acquired. On the univariate analysis, intravenous drug abuse (IVDA) (P = 0.02), history of previous Pneumocystis carinii pneumonia (PCP) (P = 0.03) and cirrhosis (P = 0.03) were significant risk factors for SAP. In addition, IVDA and previous PCP were independent risk factors on multivariate analysis. All patients presented with fever associated with cough (74%), chest pain (26%) or shortness of breath (37%). Chest X-ray documented lobar pneumonia (78%), predominantly in the lower lobes, consolidation with cavitation (11%), and interstitial-nodular infiltrates (11%). Pleural effusion was present in 31% of patients. The response to therapy was favourable in 79% of patients. Recurrence occurred in 26% and death occurred in 21% of patients. Death was significantly associated with the low level (< 50 mm-3) of circulating T CD4+ cells (P = 0.03) and the recurrence of pneumonia (P = 0.03). In conclusion, the present study indicates that S. aureus is an important aetiologic agent of bacterial pneumonia in HIV-infected patients, especially if they are drug abusers with previous PCP. 相似文献
998.
999.
The thermoelastic response to deformation of carbon-fibre/epoxy-resin composite laminates has been considered theoretically, and compared with experimental results. It is found that the surface temperature is strongly dependent on the near-surface lay-up. The total thermal response to tensile testing to failure is also reported. The results indicate that a simple, but accurate, estimation of the yield strength in composites is possible by measuring the thermoelastic limit strength, and that microstructural ‘events’ are detectable by measuring the surface temperature with sufficiently high resolution. 相似文献
1000.
A case of ectopic ureter without urinary incontinence despite its ureteral orifice in the vestibulum is reported. A 2-year-and-9-month-old female was referred to our hospital with the pain of external genitalia, pollakisuria and macroscopic hematuria. Examination revealed a complete double system of the left upper tract with vestibular opening from the upper moiety. She did not show any signs of ureteric incontinence after the establishment of voiding habits. Because radioisotope (RI) scintigram showed apparent uptake in the upper half of the left kidney we performed left ureterocystoneostomy with psoas hitch procedure. We postulate that the incontinence mechanism is maintained when the running course of the ectopic ureter is through some portion of the urethral sphincter musculature. This is the 10th case reported in Japan. 相似文献
