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11.
Mathematical models for liquid-liquid extraction processes are not widely available. The correlation of liquid-liquid equilibrium for such a model is often difficult. One correlation, based upon the Redlich-Kister expansion for the molar excess Gibb's free energy, has been shown to accurately represent ternary liquid-liquid equilibrium systems used in liquid-liquid extraction operations.
The use of this correlation in an extraction model was investigated and found to be suitable for a ternary liquid-liquid extraction model with only minor limitations. A successful ternary liquid-liquid extraction model was developed using this equilibrium correlation. 相似文献
The use of this correlation in an extraction model was investigated and found to be suitable for a ternary liquid-liquid extraction model with only minor limitations. A successful ternary liquid-liquid extraction model was developed using this equilibrium correlation. 相似文献
12.
The supply and return piping of passive solar domestic hot water systems (SDHWS) is typically exposed to ambient weather conditions, and damaging pipe freeze is a major concern. This paper presents a pipe-freeze model that accounts for hot water draws and uses 30 years of actual weather data. The simulation results are cast in terms of pipe-freeze probabilities. Using contour maps of the continental United States, the pipe-freeze probabilities for residential, commercial, and seasonal passive SDHWS are presented for various pipe and insulation geometries. 相似文献
13.
Provision of Quality‐of‐Service (QoS) guarantees is an important and challenging issue in the design of integrated‐services
packet networks. Call admission control is an integral part of the challenge and is closely related to other aspects of networks
such as service models, scheduling disciplines, traffic characterization and QoS specification. In this paper we provide a
theoretical framework within which call admission control schemes with multiple statistical QoS guarantees can be constructed
for the Generalized Processor Sharing (GPS) scheduling discipline. Using this framework, we present several admission control
schemes for both session‐based and class‐based service models. The theoretical framework is based on recent results in the
statistical analysis of the GPS scheduling discipline and the theory of effective bandwidths. Both optimal schemes and suboptimal
schemes requiring less computational effort are studied under these service models. The QoS metric considered is loss probability.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
J Moreno Sierra ML Maestro de las Casas J Chicharro Almarza MD Ortega Heredia J López García-Asenjo C Merino Sánchez E Blanco Jiménez A Silmi Moyano L Rsesel Estévez 《Canadian Metallurgical Quarterly》1997,50(8):855-866
OBJECTIVE: The clinical course of transitional cell carcinoma of the bladder can be difficult to predict due to its potential to invade the muscle layer and/or develop to a high grade lesion. Bladder carcinoma can arise from genetic changes that may activate the oncogenes (-c-erbB2, c-erbB1, c-myc, ras, etc.) and/or inactivate the suppressor genes (p53, Rb). The aim of the present study is to continue a study protocol on the molecular biology of bladder tumors. METHODS/RESULTS: From January, 1993 to January, 1995, 85 patients were studied. These patients were divided into two groups: the first group comprised 14 controls of urothelial tissue and the second comprised 65 cases of transitional cell carcinoma of the bladder. p53 expression was determined by an immunohistochemical method (NCL-p53-DO7 monoclonal antibody). Quantification of the p8 oncoprotein in cytosol and EGFR (epidermal growth factor receptor) in membrane was performed by ELISA (Oncogene Science) and RIA (Vienna Lab), respectively. A statistically significant relationship between the expression of p53 and EGFR with tumor stage and grade was found. Quantification of p185 and EGFR showed higher values in the tumor tissue than in the control samples, but a worse survival could not be determined. CONCLUSIONS: The present study shows that p53 expression can be considered to be a prognostic factor. It provides useful information on the aggressive behaviour of the tumor and has a direct relation with the survival rates. 相似文献
15.
Rosenfarb Irwin S.; Goldstein Michael J.; Mintz Jim; Nuechterlein Keith H. 《Canadian Metallurgical Quarterly》1995,104(2):259
The authors examined whether young, recently discharged schizophrenic patients from high (n?=?34) and low (n?=?14) expressed emotion (EE) families differ in their level of subclinical symptomatology during a direct interaction task. Compared with patients from low-EE homes, patients from high-EE homes showed significantly more odd and disruptive behavior with family members. High-EE relatives were more likely than low-EE relatives to respond with criticism to the first unusual thought verbalized by the patient; when this occurred, the probability of a second unusual thought was augmented. Results suggest that high-EE family members may display negative attitudes toward patients in part because they are exposed to higher levels of unusual or disruptive behavior than low-EE relatives. The data also support a bidirectional, transactional model of the relationship between relatives' EE and patient psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
16.
17.
Summary The Polymer Section of the Santa Barbara Workshop on Modeling of Materials is briefly reviewed. Motivation and need for modeling in polymer-based materials are outlined and the recommendations resulting from the workshop reported. 相似文献
18.
We present a new post processing method of simulating depth of field based on accurate calculations of circles of confusion. Compared to previous work, our method derives actual scene depth information directly from the existing depth buffer, requires no specialized rendering passes, and allows easy integration into existing rendering applications. Our implementation uses an adaptive, two‐pass filter, producing a high quality depth of field effect that can be executed entirely on the GPU, taking advantage of the parallelism of modern graphics cards and permitting real time performance when applied to large numbers of pixels. 相似文献
19.
PURPOSE: To evaluate the effectiveness, predictability, and safety of clear lens extraction to correct extreme myopia. SETTING: Clinica de Nuestra Se?ora de la Concepción, Fundación Jiménez Díaz, Madrid, Spain. METHODS: This retrospective study comprised 26 eyes of 17 highly myopic patients who had clear lens extraction and implantation of a negative-power posterior chamber intraocular lens (IOL). The IOL power was calculated using the SRK/T formula. Analyzed were visual and refractive results and intraoperative and postoperative complications. Follow-up was at least 12 months in all cases. RESULTS: Uncorrected visual acuity improved in all cases, with 80.77% of eyes achieving 20/100 or better and 42.30%, 20/40 or better. Best spectacle-corrected visual acuity (BSCVA) improved in 23 eyes (88.46%). The percentage of eyes achieving a BSCVA of 20/100 or better increased from 73.07% preoperatively to 92.30% postoperatively and the percentage achieving 20/40 or better, from 23.07 to 73.07%. Of the 26 eyes, 76.91% were within 1.00 diopter (D) of refractive error and 96.16% were within 2.00 D. No intraoperative complications occurred. Although postoperatively 3 eyes (11.53%) developed choroidal detachment and 5 (19.23%) had an intraocular pressure greater than 25 mm Hg, all had a favorable outcome. Four eyes (15.38%) developed posterior capsule opacification and had a neodymium:YAG laser posterior capsulotomy 6 months postoperatively. No retinal detachments were observed. CONCLUSION: Clear lens extraction with negative-power IOL implantation using the SRK/T formula had good effectiveness, acceptable predictability, and a low morbidity in eyes with extreme myopia over a short follow-up. A longer follow-up with more cases is needed to assess the safety of the procedure. 相似文献
20.
Kleinke Chris L.; Peterson Thomas R.; Rutledge Thomas R. 《Canadian Metallurgical Quarterly》1998,74(1):272
Two experiments were conducted in which participants looked at photographs (Experiment 1, n?=?129) or slides (Experiment 2, n?=?90) of people engaging in positive or negative facial expressions. Participants attempted to communicate these facial expressions as accurately as they could to a video camera while viewing themselves in a mirror or without viewing themselves in a mirror. Participants in a control group maintained neutral facial expressions. Participants experienced increased positive moods when they engaged in positive facial expressions and decreased positive moods when they engaged in negative facial expressions. These effects were enhanced when participants viewed themselves in a mirror. The effects of facial expressions on positive affect were stronger for participants with high private self-consciousness. Results were integrated with research identifying individuals who are responsive to self-produced versus situational cues and with theory and research on self-awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献