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101.
The phenomenon of hybridization of the backward acoustic waves propagating in a piezoelectric crystal plate has been studied. In an electrically free plate (in particular, of potassium niobate) with a crystal orientation for which a sagittal plane is the symmetry plane, the dispersion curves of backward acoustic waves exhibit points of intersection and hybridization is absent. However, for a small change in the direction of wave propagation, the dispersion curves exhibit “repulsion” and the waves become coupled. The degree of hybridization is quantitatively evaluated in terms of the hybridization coefficient, which is defined as the ratio of the total mutual energy density and the total energy density of the interacting waves. It is demonstrated that the extent of repulsion of the dispersion curves for the interacting waves is determined by the dependence of the hybridization coefficient on the product of the plate thickness and the wave frequency.  相似文献   
102.
The aim of this work was to formulate and optimize the washing performance of an alkylpolyglucoside-based dishwashing detergent. The liquid detergent was formulated with five ingredients of commercial origin: anionic (linear sodium alkylbenzenesulfonate and sodium laurylethersulfate), nonionic (C12–C14 alkylpolyglucoside) and zwitterionic (a fatty acid amide derivative with a betaine structure) surfactants, and NaCl for viscosity control. In addition to the plate test, other properties were investigated including “cloud point”, viscosity, and emulsion stability. Statistical analysis software was used to generate a central composite experimental design. Then, a second order design and analysis of experiments approach, known as the Response Surface Methodology, was set up to investigate the effects of the five components of the formulation on the studied properties in the region covering plausible component ranges. The method proved to be efficient for locating the domains of concentrations where the desired properties were met.
J. P. CanselierEmail:
  相似文献   
103.
The effect of fish treated with gamma-beams on the animal body on the whole and on some organs and tissues was studied in chronic experiments on 4 generations of Wistar rats of both sexes. The animals' status was evaluated according to the rats' appearance, behavior, and the time-course of changes in the body weight. In rats of the basic generation, the rate of tumor occurrence and tumor sites were also examined. Morphological and biochemical investigations were carried out over time, namely after 4, 8, 12 and 17 months. The measurements were taken of blood serum and liver proteins, blood sulfhydryl groups and hemoglobin, ascorbic acid in the liver and adrenals, as well as of the activity of AST, ALT and cholinesterase in the blood serum and in the liver. In the majority of cases, the findings obtained in experimental animals did not differ from those in controls.  相似文献   
104.
Under steady state conditions in 66 athletes involved in weightlifting, bodybuilding, judo and taekwondo have studied features of the metabolic status. Data on matter-of-fact nutrition, body weight content within the inter-competition period, energy exchange, clinical and biochemical indices and physical acceptability indices were analyzed. As a result, the decrease indexes of metabolism at all the sportsmen and high-level caloric value at sportsmen who are engaged in weightlifting, which corresponds their energy expenditures, was revealed.  相似文献   
105.
1 INTRODUCTIONBioleaching the complex,low grade minerals ,submarginal ore and tailings has the advantages ofshort process and low cost , which can make fulluse of resources and i mprove environment . Butbioleaching also has some li mitation such as slowspeed and low rate of leaching due to slow breedvelocity andlowactivity resultingfrombad growthcondition[1 3]. However oxygen under supplying isalso the restriction of leaching reaction.In cyaniding,oxygen supplyis veryi mportantfor leachin…  相似文献   
106.
Catamnestic data concerning 109 patients, inhabitants of Warsaw-Praga, hospitalized for the first time in the years 1978-79 with schizophrenia (92 persons) or paranoid psychosis-ICD IX number 297.9 (17 persons), were collected in 1993-94. Smaller number and shorter duration of hospitalisations has been observed during 15 years, in comparison with other Polish data. Twenty persons died during the period of observation. In the group of 85 investigated persons-69% were not working at all-15% were fully and 18% partially unable to meet their basic needs on their own-29% were temporarily or permanently unable to function adequately in their marital and/or parental roles, 31% were single and childless. Taking into account the mortality among 109 observed persons (18.7% during 15 years); good prognosis according to social functioning has been found in 48.6% of the group observed at first hospitalisation.  相似文献   
107.
BACKGROUND: To analyze the response to eradicative therapy and prognostic factors in 52 patients with primary gastrointestinal lymphoma (PGIL) diagnosed at a single institution in a 13 year period. PATIENTS AND METHODS: The main clinical, biological and evolutive data were recorded. Pathologic diagnosis of PGIL was made according to the Working Formulation. Clinical stage was determined by the Ann Arbor system modified by Mushoff. The results of therapy as well as the influence of such characteristics on complete remission (CR), disease-free survival (DFS) and overall survival (OS) were studied. RESULTS: Mean age of the series was 53 years (SD 15). Thirty patients were males. HIV infection preceded PGIL diagnosis in 10 cases. Seventeen had bad performance status (ECOG 2-4) and 30 B symptoms. The PGIL localization was gastric in 31 cases and 29 had a low grade malignant lymphoma. B phenotype was demonstrated in 98% and 22 patients presented advanced stages (IIE2-IV). Treatment was radical surgery followed by intensive chemotherapy in 32 cases, intensive chemotherapy alone in 17, and surgical resection in 3. CR was obtained in 34 patients and 6 of them relapsed. The projected DFS from CR at 9 years was 72% and OS was 26%. CR and survival were not influenced by PGIL localization and treatment type. The main unfavourable prognostic factors were advanced stage (CR and OS), B symptoms (DFS and OS) and advanced ECOG score (CR, DFS and OS). Previous HIV infection had an independent prognostic influence on both CR and OS. CONCLUSIONS: In patients with PGIL, the achievement of CR, DFS and survival have been independent of the type of eradicative treatment used. Performance status, B symptoms and clinical stage have been the main prognostic factors. HIV infection carried an independent prognostic significance.  相似文献   
108.
109.
The paper is focused on prediction of loss of consciousness and grey-out during short (up to 5 s) impulses of longitudinal head-to-tail accelerations with high buildup gradients (more than 50 m/s3). This is a poorly explored region of exposure on the borderline between impulsive and maneuvering accelerations of the modern aircraft. On the basis of comparing the prediction with available experimental data, prognostic potentials of various modifications of criterion which includes the maximum allowable values of velocity in this range of exposure are demonstrated.  相似文献   
110.
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