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11.
Hamza El Marouazi Benoit van der Schueren Damien Favier Anaëlle Bolley Samuel Dagorne Thierry Dintzer Izabela Janowska 《应用聚合物科学杂志》2021,138(44):51300
Four series of polylactide (PLA) based composite films containing horizontally aligned few layer graphene (FLG) flakes of high aspect ratio and adsorbed albumin are prepared. The mechanical and thermal properties varies with percentage, dispersion degree and size of FLG flakes. Great improvement up to 290% and 360% of tensile modulus and strength respectively were obtained for the composite containing high lateral size of FLG at 0.17% wt, and up to 60% and 80% for the composite with very well dispersed 0.02% wt FLG. The composites of PLA and PEG-PLLA containing very well dispersed FLG flakes at 0.07% wt are ductile showing enhancement of elongation at break up to respectively 80% and 88%. Relatively high electrical conductivity, 5 × 10−3 S/cm, is measured for PLA film charged with 3% of FLG. 相似文献
12.
Medico-demographic processes and socio-hygienic characteristics of the population of a large city, both at an individual and familial levels, as well as territorial characteristics of residence, should be taken into consideration when developing measures for medicosocial care of the population. Analysis of the attitude of 380 city families to the activities, personality, and professional skills of local therapists and pediatricians and to the idea of primary health care rendered by a physician of a general profile demonstrated an increased activity of the families in the "physician-patient" system and confirmed the necessity of improving medicosocial care of a city family, expansion of prophylactic work with the population with due consideration for factors which have an impact on population health. 相似文献
13.
Using the consumer-oriented approach of social and commercial marketers, this article presents a process for crafting messages designed to improve people's health behaviors. The process, termed consumer-based health communications (CHC), transforms scientific recommendations into message strategies that are relevant to the consumer. The core of CHC is consumer research conducted to understand the consumer's reality, and thereby allowing six strategic questions to be answered. The immediate result of the CHC process is a strategy statement--a few pages that lay out who the target consumer is, what action should be taken, what to promise and how to make the promise credible, how and when to reach him or her, and what image to convey. The strategy statement then guides the execution of all communication efforts, be they public relations, mass media, direct marketing, media advocacy, or interpersonal influence. It identifies the most important "levers" for contact with the consumer. Everyone from creative specialists through management and program personnel can use the strategy statement as a touchstone to guide and judge the effectiveness of their efforts. The article provides a step by step illustration of the CHC process using the 5 A Day campaign as an example. 相似文献
14.
A new controller for linear multivariable ordinary systems is suggested in which distributed delays are included in the feedback loop. A general design approach to obtain this type of controller is suggested. It is shown that the resulting closed-loop system is asymptotically stable under some sufficient conditions. Sufficient conditions are derived under which the disturbance attenuation, the robustness against parameter variations, and the time-delay stability margins are improved by the proposed controller. The state feedback tracking controller and the dual-state observer are obtained by modification of the proposed controller. 相似文献
15.
Adriana Neag Véronique Favier Régis Bigot Mariana Pop 《Journal of Materials Processing Technology》2012,212(7):1472-1480
The microstructure and flow behaviour during thixo backward extrusion of 7075 aluminium alloy were investigated. Reheating the steel die and the aluminium billet placed into the die at the same time using an induction furnace provides rapidly a very homogeneous microstructure suitable for thixoforming. During thixoextrusion, despite the high solid fraction, the solid globules are weakly connected and slide over each other without any plastic deformation. The flow remains quasi homogeneous resulting in homogeneous induced microstructure of the component. 相似文献
16.
J. Girardot P. Lorong L. Illoul N. Ranc M. Schneider V. Favier 《International Journal of Material Forming》2017,10(2):205-219
The laser drilling process is the main process used in machining procedures on aeronautic engines, especially in the cooling parts. The industrial problematic is to reduce geometrical deviations of the holes and defects during manufacturing. The interaction between a laser beam and an absorbent metallic matter in the laser drilling regime involves thermal and hydrodynamical phenomenon. Their role on the drilling is not yet completely understood and a realistic simulation of the process could contribute to a better understanding of these phenomenon. The simulation of such process induces strong numerical difficulties. This work presents a physical model combined with the use of the original Constraint Natural Element Method to simulate the laser drilling. The physical model includes solid/liquid and liquid/vapor phase transformations, the liquid ejection and the convective and conductive thermal exchanges. It is the first time that all these phenomena are included in a modelling and numerically solved in a 2D axisymmmetric problem. Simulations results predict most of measurements (hole geometry, velocity of the liquid ejection and laser drilling velocity) without adjusting any parameters. 相似文献
17.
对马来酸酐改性制成的长焰煤加合物的阳离子交换性进行研究,并同氧化煤和工业吸附剂作了对比,表明其亲质子基团的解离范围宽(pK3.6~6.5)。从水溶液中吸附多价金属阳离子的能力取决于阳离子交换剂的表面性质:该加合物对Cr、Fe、Pb的吸附活性高于КБ-4阳离子树脂。 相似文献
18.
19.
IG Nikitin SL Kuznetsov GI Storozhakov OD Liuliaeva 《Canadian Metallurgical Quarterly》1998,76(6):41-44
AIM: This study of trimetasidine effects on plasmic hemostasis and blood biochemistry in patients with chronic heart failure (CCF) of NYHA functional class II-III. MATERIALS AND METHODS: This study enrolled 30 patients (24 males and 6 females) aged 40-72 years with class II-III CCF, postinfarction cardiosclerosis and ejection fraction under 40%. Previously the patients received perindopril (the inhibitor of angiotensin converting enzyme) in daily dose 2-4 mg, on-demand digoxin and diuretics. Trimetasidine was given in a daily dose 60 mg for 6 months. Before and after the treatment the patients' blood was examined for: levels of factors VII and X of antithrombin III coagulation, soluble fibrinomonomeric complexes (SFMC), fibrinogen, glucose, uric acid, creatinines, total cholesterol, high density lipoprotein, triglycerides, AST, ALT, LDH, acid phosphotase, gamma-GT, sodium, potassium, activated partial thrombin time. RESULTS: Initially, the patients had a 23.9% increase in the levels of factors VII and X, a 14.3% decrease of antithrombin III, 29.8 and 227.6% rise in concentrations of fibrinogen and SFMC, respectively, compared to controls. Aftertreatment values of fibrinogen, factors VII and X, SFMC fell by 21.1, 17 and 35.5%, respectively. The thrombin time arose by 17.9% (p > 0.05). Insignificant inhibition was registered in the activity of acid phosphotase and gamma-GT. Glucose, AST, ALT, LDH levels remained unchanged. Plasma creatinine tended to lowering. Total cholesterol insignificantly increased at high levels of HDL cholesterol (p > 0.05) and reduced levels of triglycerides (p > 0.05). CONCLUSIONS: Trimetasidine therapy, given after conventional treatment with diuretics, digoxin, inhibitor of angiotensin-converting enzyme, aspirin has a beneficial effect in patients with circulatory deficiency through improving hemostatic and biochemical parameters. 相似文献
20.
We reviewed the use of a low radiation portable fluoroscopy unit in 100 patients. The most common indication was closed reduction of distal radial fractures. Fracture and joint stability were assessed on the real-time monitor and stored on videotape. Static images were stored on thermographic paper. Fluoroscopically guided joint injections and localization of implants, foreign bodies and bone tumours were performed. Fluoroscopy is a useful adjunct to arthroscopic assisted fracture reduction and other arthroscopic procedures such as distal ulnar resection. These new generation units produce superior resolution images, are easy to manoeuvre and do not require a radiographer. 相似文献