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1.
Tolmachev A. M. Kuznetsova T. A. Fomenkov P. E. 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(3):433-436
Protection of Metals and Physical Chemistry of Surfaces - The conditions for carrying out molecular dynamics calculations of adsorption isotherms of gases and vapors in micropores of active carbons... 相似文献
2.
Cellulose diacetate and triacetate films 6–55 µm thick with a total porosity of 0.8–2% were prepared by pouring a solution on an immobile surface and by calendering. Sorption of H2S and CO2 gases and acetone vapors on these films was investigated in static and dynamic conditions. It was shown that films 6–10 µm thick prepared by calendering should be used for purification of air from H2S and CO2 and films 15–20 µm thick prepared by pouring should be used for removal of acetone vapors.Engels Institute of Technology, Saratov State University. Translated from Khimicheskie Volokna, No. 6, pp. 44–46, November–December, 1995. 相似文献
3.
TV Perneger P Chopard FP Sarasin JM Gaspoz C Lovis PF Unger AF Junod FA Waldvogel 《Canadian Metallurgical Quarterly》1997,157(13):1495-1500
OBJECTIVE: To identify patient- and admission-related risk factors for a medically inappropriate admission to a department of internal medicine. METHODS: Cross-sectional study of a systematic sample of 500 admissions to the department of internal medicine of an urban teaching hospital. The appropriateness of each admission and reasons for inappropriate admissions were assessed using the Appropriateness Evaluation Protocol. Risk factors included the time (day of week and holidays) and manner (through emergency department or direct admission) of admission, patient age and sex, health status of patient and spouse, living arrangements, formal home care services, and informal support from family or friends. RESULTS: Overall, 76 (15.2%) hospital admissions were rated as medically inappropriate by the Appropriateness Evaluation Protocol. In multivariate analysis, the likelihood of an inappropriate admission was increased by better physical functioning of the patient (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.1-2.1 [for 1 SD in Physical Functioning scores]), lower mental health status of the patient's spouse (OR, 2.6; 95% CI, 1.3-5.6), receipt of informal help from family or friends (OR, 3.3; 95% CI, 1.5-7.2), and hospitalization by one's physician (OR, 3.6; 95% CI, 1.7-7.5). Receiving formal adult home care was not associated with inappropriateness of hospitalization. CONCLUSIONS: Inappropriate admissions to internal medicine wards are determined by a mix of factors, including the patient's health and social environment. In addition, the private practitioners' discretionary ability to hospitalize their patients directly may also favor medically inappropriate admissions. 相似文献
4.
Felix Rivkin Irina Kuznetsova Nadezhda Ivanova Sergey Suhodolsky 《Soil Mechanics and Foundation Engineering》2002,39(1):42-43
Soil Mechanics and Foundation Engineering - 相似文献
5.
OBJECTIVE: Treatment with metformin is occasionally associated with the development of severe lactic acidosis. However, this is usually observed in patients with major contraindications to the drug. In this study, we aimed to determine the prevalence of conditions currently regarded as either contraindications or cautions to the use of metformin in patients with NIDDM. RESEARCH DESIGN AND METHODS: The case notes of metformin-treated NIDDM patients (mean age 62 years) attending a United Kingdom university hospital diabetes clinic over a 3-month period were reviewed according to criteria reflecting a pragmatic view of current prescribing recommendations. RESULTS: Of 89 consecutive patients whose notes could be evaluated in detail, only 41 (46%) had no contraindications or cautions to metformin whatsoever. Concomitant chronic disorders associated with a potentially increased risk of hyperlactatemia were renal impairment (n = 2; plasma creatinine concentrations 1.7 and 2.3 mg/dl, respectively), cardiac failure (n = 2), and chronic liver disease (n = 2). Other potentially relevant disorders included ischemic heart disease (n = 20), clinical proteinuria (n = 14), peripheral vascular disease (n = 22), and pulmonary disease (n = 7). Multiple conditions (i.e., two, three, or four) were present in eight, five, and one patient(s), respectively. CONCLUSIONS: More than half the patients in our series had concomitant conditions or complications conventionally regarded as cautions or contraindications to metformin; approximately 10% had a multiplicity of such conditions. Regular surveillance is necessary to detect the development of complications such as renal impairment. Vigilance is also required in view of the increased risk of major intercurrent illnesses, which may independently disturb lactate metabolism in patients with NIDDM. Metformin should be withdrawn promptly under such circumstances. 相似文献
6.
NG Darenskaia AO Korotkevich SS Kuznetsova TA Nasonova 《Canadian Metallurgical Quarterly》1997,37(3):423-430
Radiation sickness manifestations have been studied in dogs exposed to electrons (electron energy 25 MeV) and gamma-neutron radiation (neutron energies of 0.37 and 1.2 MeV) in a wide dose range. Dose-response relationships have been calculated for mortality and some clinical manifestations of the intestinal and cerebral forms of radiation sickness. With regard to mortality, the highest effect has been observed for gamma-neutron radiation with a neutron energy of 1.2 MeV. For equal physical doses and for those equally effective in relation to mortality, clinical manifestations of damage are more prominent following exposure to electrons. 相似文献
7.
From 1986 through to 1990 a total of 483 in situ bypass procedures were performed in 444 patients. Preoperative risk-factors were equally distributed among diabetic (DM) and non-diabetic (NDM) patients, except for smoking habits (DM:48%, NDM:64%, p = 0.002) and cardiac disease (DM:45%, NDM:29%, p = 0.005). Critical limb-ischaemia was more often present in diabetic than non-diabetic patients (DM:57%, NDM:36%, p = 0.0002). Diabetic patients had a significantly lower distal anastomosis than non-diabetic patients (p = 0.00001). There were no differences among diabetic and non-diabetic patients regarding three years primary and secondary patency (58% and 64% respectively), and regarding major amputations. However, the rate of minor amputations was higher in insulin-dependent compared with non-insulin-dependent diabetics, who in turn had a higher rate than non-diabetics (p < 0.00001). A markedly decreased survival rate was found in diabetics (p < 0.00005). We found the in situ bypass technique very useful in the treatment of critical ischaemia of the lower limb in diabetic patients. The overall results in diabetic patients, whether insulin-dependent or not, were equal to those in non-diabetic patients. 相似文献
8.
Borodina I. A. Zaitsev B. D. Kuznetsova I. E. Teplykh A. A. Shurygin V. V. 《Technical Physics Letters》2003,29(9):781-783
The conditions for hybridization of the zero-order and high-order acoustic waves propagating in a piezoelectric crystal plate have been studied. The dependence of the phase velocity of the hybrid waves on the parameter hf (h is the plate thickness and f is the wave frequency) is established for the potassium niobate and lithium niobate plates possessing various crystallographic orientations and conductivities. It is found that hybridization takes place when the conductivity of a thin surface layer exceeds a certain critical value, which can vary within broad limits depending on the plate material and orientation. The degree of dispersive repulsion of the coupled modes grows with increasing electromechanical coupling coefficient. 相似文献
9.
P. A. Storozhenko G. I. Shcherbakova A. M. Tsirlin A. S. Murkina M. S. Varfolomeev M. G. Kuznetsova M. V. Polyakova O. P. Trokhachenkova 《Inorganic Materials》2007,43(3):320-328
Chelated alkoxyalumoxane oligomers have been synthesized through consecutive hydrolysis and alcoholysis of organoaluminum compounds stabilized by compounds capable of keto-enol tautomerism. The chelated alkoxyalumoxanes were used to prepare a silica-free binder for the fabrication of heat-resistant (up to 2050°C), chemically inert corundum ceramic composites. The likely structures of the synthesized preceramic alumoxane oligomers were inferred from physicochemical characterization results (1H, 13C, and 27Al NMR, IR spectroscopy, mass spectrometry, gel-permeation chromatography, thermal analysis, and elemental analysis). 相似文献
10.
It is shown that technetium can be extracted from acidic media by the fibrous complexing sorbent POLIORGS 35, containing hydrazidine groups, and from neutral and nitric-acid solutions with a complex salt composition (with nitrate-ion concentration not exceeding 10 g/liter) by strongly basic anionite POLIORGS AV-17 with quaternary ammonium bases. The effect of the pH of the solutions on the sorption of technetium is studied. It is shown that the sorption depends on the nature and concentration of the salt background of the solutions. The kinetics and mechanism of sorption of technetium by fibrous sorbents and the possibility of their desorption and reuse in sorption–desorption cycles are investigated. It is shown that the fibrous sorbents POLIORGS 35 and POLIORGDS AV-17 are promising for extracting technetium from waters with a high mineral content (up to 20 g/liter). 相似文献