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141.
SOLIDS TRANSPORTATION MODEL OF AN INDUSTRIAL ROTARY DRYER 总被引:1,自引:0,他引:1
A complete simulation model has been developed for an industrial rotary dryer to account for the heat and mass exchange between the solids and the gas. This simulator is mainly composed of three models: solids transportation model, furnace model, and gas model. The solids transportation model is the modified Cholette-Cloutier model It consists of a series of interactive reservoirs which are subdivided into an active and a dead compartments to account for the characteristic extended tail of the residence time distribution (RTD) curves observed in industrial dryers.
To expand the validity of the model, experiments have been performed in an industrial rotary dryer to obtain RTD curves under different mineral concentrate and gas flow rates. This paper describes these experiments and presents the variation of the average residence time and model parameters as function of solids and gas flow rates. 相似文献
To expand the validity of the model, experiments have been performed in an industrial rotary dryer to obtain RTD curves under different mineral concentrate and gas flow rates. This paper describes these experiments and presents the variation of the average residence time and model parameters as function of solids and gas flow rates. 相似文献
142.
The Data Encryption Standard (DES) is a cipher that is still used in a broad range of applications, from smartcards, where it is often implemented as a tamper-resistant embedded co-processor, to PCs, where it is implemented in software (for instance, to compute crypt(3) on UNIX platforms). To the authors’ knowledge, implementations of DES published so far are based on the straightforward application of the NIST standard. This article describes an innovative architecture that features a speed increase for both hardware and software implementations, compared to the state of the art. For example, the proposed architecture, at constant size, is about twice as fast as the state of the art for 3DES-CBC. The first contribution of this article is an hardware architecture that minimizes the computation time overhead caused by key and message loading. The second contribution is an optimal chaining of computations, typically required when “operation modes” are used. The optimization is made possible by a novel computation paradigm, called “IP representation”. 相似文献
143.
Errol M Thomson Andrew Williams Carole L Yauk Renaud Vincent 《Particle and fibre toxicology》2009,6(1):6-18
Background
Individuals with chronic lung disease are at increased risk of adverse health effects from airborne particulate matter. Characterization of underlying pollutant-phenotype interactions may require comprehensive strategies. Here, a toxicogenomic approach was used to investigate how inflammation modifies the pulmonary response to urban particulate matter. 相似文献144.
145.
Oechsner R. Pfeffer M. Frickinger J. Schellenberger M. Roeder G. Pfitzner L. Ryssel H. Fritzsche M. Kaushik V. Renaud D. Danel A. Claeys C. Bearda T. Lering M. Graef M. Murphy B. Walther H. Hury S. 《Semiconductor Manufacturing, IEEE Transactions on》2007,20(3):215-221
This paper describes the objectives and results of a joint European project named FLYING WAFER. The goal of the project was to provide a methodology for interlinking European R&D centers in micro and nano technologies to a distributed 300-mm CMOS R&D line. The project was carried out as a feasibility study. Therefore, the results provide a model and concept which has the potential of guaranteeing a safe and fast exchange of wafers and data between European R&D nodes to allow multisite processing. An implementation phase is planned as a second step. 相似文献
146.
D.R. Wood R.M. Blome L.C. Ribeiro A.J. Keunen B.W. Keunen G.W. Smith D.L. Renaud 《Journal of dairy science》2021,104(1):957-962
Calf diarrhea can commonly lead to dehydration and metabolic acidosis due to the loss of fluid and electrolytes. The objective of this randomized clinical trial was to examine differences between treating male dairy calves experiencing diarrhea with either a basic bicarbonate electrolyte powder (BBP) composed of sodium bicarbonate (50.7 mmol/L); a mixed buffer powder (MBP) including sodium bicarbonate (33.8 mmol/L), sodium citrate (8.4 mmol/L), sodium acetate (6.3 mmol/L), and potassium citrate (1.9 mmol/L); or a liquid electrolyte (HAL) composed of sodium acetate (50.1 mmol/L). All 3 electrolyte solutions were standardized to provide 50 mmol/L blood buffers and a similarly strong ion difference (74.4, 74.9, and 82.6 mEq/L for BBP, MBP, and HAL, respectively). Holstein male calves (n = 80) were sourced from auction barns or local farms and delivered in 1 batch to the research facility. Calves were housed in individual pens and fed a 24% crude protein and 17% fat calf milk replacer (CMR) twice daily. Starter grain and water were offered ad libitum. Calves were randomly enrolled in 1 of the 3 treatments when experiencing either 2 consecutive days of a fecal score of 2 (runny, spreads easily) or 1 d with a fecal score of 3 (liquid devoid of solid material). Calves were blocked by the different enrollment criteria. The respective electrolyte solution was administered via esophageal tube 1 h after feeding CMR until the fecal score returned to 0 (normal consistency) or 1 (semiformed or pasty). Blood gas measurements were taken at 1, 8, and 24 h post the initial electrolyte feeding, and weight was measured at 1, 2, 7, 14, and 28 d postenrollment. Mixed repeated measure linear regression models were built to assess the effect that the electrolyte solutions had on the blood gas measurements and body weight. A total of 45 calves were enrolled in the trial with 14, 16, and 15 calves randomly assigned to the MBP, HAL, and BBP groups, respectively. As compared with BBP, MBP increased blood CO2 at 8 and 24 h, increased bicarbonate at 24 h, increased base excess at 8 and 24 h, and increased anion gap at 24 h. Calves in the BBP and HAL groups noted more severe eye recession when compared with the MBP group. Average daily gain did not differ between treatments at any time point. Although a severe dehydration challenge was not present, which should be considered a limitation of the study, MBP improved the acid-base status of calves compared with BBP, whereas HAL performed similarly to MBP. 相似文献
147.
H.M. Goetz D.F. Kelton J.H.C. Costa C.B. Winder D.L. Renaud 《Journal of dairy science》2021,104(1):874-885
There is a strong need for management strategies that help reduce the incidence of disease and subsequent antimicrobial use in the veal industry. Biomarkers could serve as useful tools that allow producers to take preventative measures before clinical problems occur. The objective of this prospective cohort study was to identify biomarkers measured upon arrival associated with morbidity, mortality, and average daily gain (ADG) in grain-fed veal calves. Upon arrival at a grain-fed veal facility in Ontario, Canada, calves were weighed and health-scored using a standardized health-scoring system. Several metabolites were measured including creatine kinase (CK), cholesterol, haptoglobin, manganese, serum total protein, iron, cobalt, zinc, selenium, molybdenum, and IgG. Farm personnel treated calves according to their farm protocol and weighed them at 78 d after arrival. Performance, treatment, and mortality records from the facility were used for analysis. Multivariable Cox proportional hazard models were created to evaluate metabolic biomarkers associated with morbidity and mortality. A mixed linear regression model was created to determine biomarkers associated with ADG. A total of 992 male dairy calves were evaluated at arrival from January to December 2017. Of the calves evaluated, 74 calves (7.5%) died and 877 (88.4%) were treated for illness over the 11-wk period under observation. Higher levels of haptoglobin and molybdenum were associated with a greater hazard of morbidity, whereas higher weight upon arrival and higher levels of both CK and IgG were associated with a reduced hazard of morbidity. For mortality, higher weight upon arrival and higher levels of cholesterol and IgG were associated with a lower hazard of mortality occurring over the 78-d period of observation. Higher weight, cholesterol, copper, CK, iron, and IgG were associated with increased ADG, whereas increased zinc and haptoglobin were negatively associated with ADG. These results demonstrate that certain biomarkers could be used to identify high-risk calves when measured upon arrival at a veal facility. Future research should focus on determining the utility of these biomarkers to selectively target intervention strategies to improve ADG and reduce morbidity and mortality. 相似文献
148.
Jourdan A. Chiaroni D. Dotaro E. Eilenberger G.J. Masetti F. Renaud M. 《Communications Magazine, IEEE》2001,39(3):136-141
This article analyses the rationale and technical solutions for the use of optical packet switching techniques for both backbone and metropolitan applications. It also provides information on state-of-the-art technologies available for medium-term product development 相似文献
149.
150.
The solids mean residence time in a rotary dryer is influenced by several variables such as dryer dimensions and solids characteristics. One of these characteristics, usually not taken into account in correlations proposed to estimate the mean residence time, is the solids feed moisture content. Although it is well known that the solids moisture content has a major impact on the ability of the solids to move along the rotary dryer, it does not enter as a parameter in available correlations. In this investigation, numerous experiments were performed in a pilot-scale rotary dryer to study the influence of solids moisture content and drying gas temperature on the mean residence time. Sand employed in cement makeup was used to perform these experiments. Results show that the mean residence time for a moisture content in the range of 8% to 12% is four times higher than for dry solids. The moisture content and the drying gas temperature influence significantly the shape of the residence time distribution curve. 相似文献