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991.
Using a viscometer that operates up to a maximum pressure of 29.4 MPa and a maximum temperature of 550 °C, the viscosity of coal paste and its changes with temperature were investigated, and also some effects of: type of vehicle oil, coal to vehicle oil ratio, coal particle size, atmosphere, pressure, catalyst and coal rank. In the viscosity-temperature curve for the paste from high rank bituminous coals, a peak was observed near 300 °C, which is considered to be due to the extractive disintegration of the coal by the vehicle oil. Under hydrogenation with high pressure hydrogen and hydrogenation catalyst, the extractive disintegration of coal was promoted, and the viscosity was higher than that in nitrogen atmosphere. The viscosity behaviour of the coal paste from low rank coals was the same as that of the vehicle oil alone.  相似文献   
992.
The dynamic tensile deformation mechanism of spherulitic poly-alpha-olefins, high-density polyethylene, isotactic polypropylene, and isotactic polybutene-1, was investigated by dynamic X-ray diffraction at various temperatures and frequencies in order to assign the α and β mechanical dispersions explicitly. The uniaxial orientation distribution function qjj, 0) of the j-th crystal plane and its dynamic response Δqj′(ζj, 0) in-phase with dynamic strain were observed for several crystal planes, and then the orientation distribution function ω(§, 0, η) of crystallites (crystal grains) and its dynamic response Δω′(§, 0, η), also in-phase with the dynamic strain, were determined by a mathematical transformation procedure proposed by Roe and Krigbaum on the basis of the Legendre addition theorem. The temperature and frequency dependences of Δω′(§, 0, η) were analyzed in terms of a spherulite deformation model combining affine orientation of crystal lamellae with several types of preferential reorientation of the crystal grains within the orienting lamellae. The following assignments are made: (1) the a mechanical dispersion must be assigned to the dynamic orientation dispersions of crystal grains within lamellae involving two types of preferential rotations of the grains associated with lamellar detwisting mostly in the equatorial zone of uniaxially deformed spherulites and with lamellar tilting mostly in the polar zone of the spherulites. Both processes are intralamellar grain-boundary phenomena, and the former process of lamellar detwisting is hardly activated for polypropylene and polybutene-1 spherulites in contrast to polyethylene spherulites. (2) The β mechanical dispersion must be assigned to the dynamic orientation dispersion of the crystal lamellae behaving as rigid bodies unaccompanied by reorientation of crystal grains within the orienting lamellae. This process is an interlamellar grain-boundary phenomenon.  相似文献   
993.
Chronic, nonproductive cough and cough associated with the use of angiotensin converting enzyme inhibitors, are more frequently observed in females as compared to males. To examine the influence of sex, age, height, weight and pulmonary function on airway cough sensitivity, cough threshold to inhaled capsaicin, an index of the airway cough sensitivity, was measured in 160 nonsmoking, nonatopic healthy subjects. Forty young males (aged 24 +/- 2 yrs) 40 young females (aged 22 +/- 2 yrs) 40 middle-aged males (aged 48 +/- 5 yrs) and 40 middle-aged females (aged 50 +/- 7 yrs) were studied. The cough threshold was defined as the lowest concentration of inhaled capsaicin causing five or more coughs. The cough threshold was 3-5 fold lower in females than in males both in young (p<0.001) and middle-aged (p<0.005) subjects. Cough threshold was weakly but significantly correlated to height, weight, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) when all subjects were considered together but not when each group was considered separately. Multiple regression analysis revealed that sex difference was the significant predictive factor for the cough threshold in either age group. These results confirm that cough sensitivity is heightened in females and suggest that influence of height and pulmonary function on the cough threshold may have resulted from sex difference.  相似文献   
994.
PURPOSE/OBJECTIVES: To discuss the causes, clinical manifestations, and consequences of diarrhea in the patient with cancer; to describe the oncology nurse's role in the assessment, management, and treatment of cancer-related diarrhea. DATA SOURCES: Synthesis of published peer-reviewed data, professional experience. DATA SYNTHESIS: The many causes of cancer-related diarrhea include specific types of cancer and specific anticancer treatment regimens (e.g., chemotherapy, radiotherapy). Poorly controlled diarrhea may result in a range of physiologic and psychological effects that extend beyond the patient to significant others and caregivers. Comprehensive assessment of diarrhea is the foundation for the appropriate use of pharmacologic and supportive therapies. CONCLUSIONS: Diarrhea, much like fatigue, is a symptom that only recently has become a focus of oncology nursing research and focused intervention. IMPLICATIONS FOR NURSING PRACTICE: Oncology nurses can significantly influence the quality of care given to patients who develop diarrhea as a symptom of cancer or as a sequela of cancer therapy. As such, oncology nurses are challenged to maintain current knowledge of the causes and available treatment strategies for cancer-related diarrhea. Nurses need to rely on their experiential skill and a working knowledge of published research to identify patients at risk. They also must communicate effectively with patients and caregivers in every practice setting about the nature of diarrhea and its causes, as well as develop appropriate interventions for each individual.  相似文献   
995.
Molecular simulations in the virtual material laboratory   总被引:2,自引:0,他引:2  
A virtual reality system for atomic behavior in materials testing is developed. The system is called the virtual material laboratory (VML). VML aims to help scientists make discoveries by improving their perception of data describing the atomic world and of predictions of computer simulation in atomic scale. This paper describes the VML system under developing which consists of a force display, a visual display, and simulator. Each component of VML is connected with network and exchanged data such as atomic positions from each other. We have developed a control algorithm between each component to make a real-time simulation. A molecular dynamics (MD) simulation was carried out as an example to investigate atomic behaviors and to prove the feasibility of the VML constructed.  相似文献   
996.
997.
MOS LSI process evaluation techniques based on electrical measurements are presented. Important processing parameters, such as gate length, gate oxide thickness, junction depth and channel doping which determine major device characteristics, e.g. threshold voltage and gain factor, are evaluated by electrical measurements, and compared with those measured by optical or in-process monitoring methods. Good agreement between these results indicates the effectiveness of this electrical evaluation technique. According to the analysis, threshold voltage variations across the wafer are primarily due to variations in gate oxide thickness, while anomalous threshold voltage reduction in the short channel region is attributed to MOSFET punch-through.  相似文献   
998.
The volatile flavour components of Allium grayi Regal have been investigated by a combination of chromatographic and spectroscopic methods. Among the more than 90 component peaks observed by capillary gas chromatography of the oil obtained by ether extraction of the steam distillate, 47 compounds were positively identified. They included 11 sulphur compounds, 5 alcohols, 7 aldehydes, 3 ketones, 2 furanones and 19 miscellaneous compounds.  相似文献   
999.
Four mid-lactation Holstein dairy cows (mean milk yield on day of experiments 26.1 kg/d) were used in a series of experiments to establish the contribution of non-insulin-mediated glucose uptake to total glucose uptake at basal insulin concentrations. A secondary objective was to determine whether somatostatin affects the action of infused insulin. In part I of the experiment a primed continuous infusion [6,6-2H]glucose (45.2 micrograms/kg per min) was begun at time 0 and continued for 5 h. After 3 h of [6,6-2H]glucose infusion (basal period) a primed continuous infusion of insulin (0.001 i.u./kg per min) was administered for 2 h. Coincidental with the insulin infusion, normal glucose was also infused in order to maintain the plasma glucose concentration at euglycaemia. Part II of the experiment was the same as part I except that somatostatin was infused for 2 h (0.333 micrograms/kg per min) instead of insulin. In part III of the experiment both insulin and somatostatin were infused for the final 2 h. Plasma insulin levels were increased by insulin infusion (to 0.1476 to 0.1290 i.u./l for parts I and III respectively) and were reduced by somatostatin infusion in part II (to 0.006 i.u./l) relative to the basal periods (mean 0.021 i.u./l). Glucose uptake during somatostatin infusion (2.50 mg/kg per min; part II) was 92.0% of that observed in the respective basal period (2.72 mg/kg per min). Circulating insulin levels were much lower than the dose of insulin that causes a half maximal effect on glucose uptake (0.06-0.10 i.u./l for ruminants); consequently insulin-mediated glucose uptake was probably absent in part II. Secondly, glucose uptake following insulin only infusion (4.05 mg/kg per min) was significantly lower than that observed when insulin plus somatostatin was infused (4.69 mg/kg per min), indicating that somatostatin either directly or indirectly enhanced the action of insulin on glucose uptake.  相似文献   
1000.
We report on three cases in which shunt devices (Sophy programmable pressure valve) broke while implanted in the hypochondriac region. None of these patients had an apparent history of trauma related to the shunt valve. The outlet connector was broken at the same site in each case. The dissociation between the movement of the thorax and that of the abdomen may have caused the formation of a crack in the outlet connector.  相似文献   
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