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Ideal-gas thermodynamic properties for natural-gas applications   总被引:2,自引:0,他引:2  
Calculating caloric properties from a thermal equation of state requires information such as isobaric heat capacities in the ideal-gas state as a function of temperature. In this work, values for the parameters of thec p 0 correlation proposed by Aly and Lee were newly determined for 21 pure gases which are compounds of natural gas mixtures. The values of the parameters were adjusted to selectedc p 0 data calculated from spectroscopic data for temperatures ranging from 10 to 1000 K. The data sources used are discussed and compared with literature data deduced from theoretic models and caloric measurements. The parameters presented will be applied in a current GERG project for evaluating equations of state (e.g., the AGA 8 equation) for their suitability for calculating caloric properties.  相似文献   
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Hemispheric involvement in reasoning abilities has been debated for some time, and it remains unclear whether the right hemisphere's involvement in problem solving is modality specific or dependent on the type of spatial reasoning required. In the current study, 2 types of nonverbal reasoning abilities were examined, spatial reasoning and proportional reasoning, in 109 patients with cerebrovascular disease that was confined to either the right or the left hemisphere or was diffuse in nature. Results indicated that no lateralizing effects were present based on type of spatial reasoning. Findings are consistent with the suggestion that higher order cognitive processes involved in nonverbal abstraction and problem solving are not strongly lateralized to the right hemisphere but rather are more generally distributed throughout the cortex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
The influence of heat transfer processes in arc discharges on the development of thermal instability is considered. A substantial dependence of the process of destabilization on the plasma properties is shown by the example of argon and helium arcs. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 70, No. 1, pp. 93–98, January–February, 1997.  相似文献   
998.
Anti-CEA-scintigraphy turned out very reliable in detecting primary and recurrent colorectal cancer, its overall accuracy being more than 90 p.c. The intraoperative application of this technology should provide similar results when focussing at extrahepatic tumor deposits, for example in lymph nodes, thus allowing accurate staging of the underlying disease. To test this hypothesis we lauched the following feasibility-study the results of which are compared to those reported in the recent literature. We investigated 20 patients-six with rectum-, 14 with colon cancer, 24 hours before surgery they were intravenously given 1 ml of an fab-fragment-antibody to CEA, labeled with 25mCi of 99mTc (CEA-Scan). During surgery the radioactivity in lymph glands regionary for the tumors was measured and compared to the-much lower-activity in healthy nodes. For this we used a scintillation-probe (C-Trak). All lymph nodes of interest were-then excised and submitted to frozen section pathology. In 7/20 cases scintimetry led to an up-staging of the disease. In addition we found metastatic spread to lymph nodes that were basically not regionary for the primary tumor. Our results are confirmed by those of other investigators. Scintimetry can precisely identify even very small tumor deposits. So it leads to accurate staging when surgery is still on-going. In a next step the concept of sentinel-node-diagnosis, which is right now being clinically evaluated, may be applied is colorectal surgical oncology.  相似文献   
999.
The surgical management of intractable epistaxis by external carotid artery ligation may become complicated if there is a high bifurcation of the common carotid artery. Occlusion of the bleeding vessels by catheter embolization is described in a patient in whom exploration of the neck had failed to locate the external carotid artery.  相似文献   
1000.
PURPOSE: To examine vascular associations with pseudoexfoliation syndrome in view of the wide-spread elastosis now demonstrated in this disorder that affects many tissues, including vessel walls. METHODS: The Blue Mountains Eye Study is a population-based study of eye disease in an area west of Sydney, Australia. Of 4433 eligible persons aged 49 years or older, 3,654 (82.4%) participated. Signs of pseudoexfoliation were graded clinically, after excluding 108 people who had bilateral cataract surgery. RESULTS: Pseudoexfoliation was present in 81 (2.3%) of 3546 participants aged 49 years or older. The prevalence of pseudoexfoliation increased with age and was higher in women and in people with glaucoma. Pseudoexfoliation was statistically significantly associated with a history of angina or hypertension or a combined history of angina, acute myocardial infarction, or stroke. CONCLUSION: Slit-lamp signs of pseudoexfoliation may identify individuals with an increased vascular risk.  相似文献   
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