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Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m~2) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 3...
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Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m~2) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 31, 2005, at a small natural wetland located in the alluvium of the Canadian River near Norman, Oklahoma, at the U.S. Geological Survey Norman Landfill Toxic Substances Hydrology Research Site. Floating pan evaporation rates were compared with evaporation rates from a nearby standard Class A evaporation pan on land. Floating pan evaporation rates were significantly less than land pan evaporation rates for the entire period and on a monthly basis. Results indicated that the use of a floating evaporation pan in a small free-water surface better simulates actual physical conditions on the water surface that control evaporation. Floating pan to land pan ratios were 0.82 for March, 0.87 for April, 0.85 for May, 0.85 for June, 0.79 for July, and 0.69 for August.
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Several overseas cane sugar industries are implementing steam efficient practices in factory processing in order to achieve greater economic value from bagasse, e.g. from cogenerated export power, paper pulp, particle board and (m...
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Several overseas cane sugar industries are implementing steam efficient practices in factory processing in order to achieve greater economic value from bagasse, e.g. from cogenerated export power, paper pulp, particle board and (maybe soon) second generation biofuels and chemicals. Many of these factories have installed falling film evaporators as part of the drive to steam efficiency. More recently, strong interest is developing in using vertical continuous vacuum pans (CVPs) with mechanical agitation to undertake evaporative crystallisation on low pressure vapour (e.g. using vapour 3 or vapour 4 bled from the evaporators). The cane sugar industry to now has mostly used horizontal CVPs as the horizontal layout provides several advantages over the vertical orientation. However, besides the suitability to readily incorporate mechanical agitation, vertical CVPs provide other benefits such as ease of bypassing a module for cleaning. This paper examines the advantages and disadvantages of the two continuous pan layouts. Aspects that are considered are the implications for steam efficiency, relative crystallisation rates, quality of the size distribution in the product massecuites and operator friendliness. A flowscheme is proposed for Australian factories to utilise horizontal and vertical CVPs for the production of A and B massecuites using vapour 3 (or vapour 4). The use of the SRI magma preparation system would provide for fully continuous operation of plant for the high grade massecuite production.
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The sugar factory of Sucrerie de Bois Rouge in Reunion had experienced problems with the performance and quality of sugar from their 120 m~3, 1200 m~2 heating surface horizontal steam tube A continuous pan. The problems included: ...
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The sugar factory of Sucrerie de Bois Rouge in Reunion had experienced problems with the performance and quality of sugar from their 120 m~3, 1200 m~2 heating surface horizontal steam tube A continuous pan. The problems included: rapid incrustation after boil-outs leading to poor average heat transfer rates (HTCs); poor crystal quality; high entrainment rates, especially immediately following boil-outs; 'dark specks' in the product sugar; and low massecuite brix and poor exhaustions. Management was concerned that these problems would be more severe when they planned to boil higher purity A massecuites in future. It was therefore decided to convert the pan to a vertical massecuite tube configuration by installing a new calandria and massecuite baffling, all within the existing pan body. Bosch Projects undertook the design, incorporating the key features of their own standard CVPs. The conversion required reducing the pan volume to 100 m~3 with a 1024 m~2 heating surface, but the designers were confident that the performance of the modified pan would meet the factory's requirements. The pan entered service in its new form in July 2012. This paper describes the conversion project and reports comparative performances of the pan between the original horizontal tube configuration and its converted vertical tube configuration. With the modified pan, intervals between cleaning are three times longer, HTCs are 50％ greater, brixes are three units higher and pan exhaustions 5-6 units better. The conversion provides a viable solution for others experiencing similar difficulties.
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As an important constituent of hydrological cycle, estimation of Reference Evapotranspiration (ETo) is essential for planning of projects related to water resources. This article compares the results obtained from the available pa...
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As an important constituent of hydrological cycle, estimation of Reference Evapotranspiration (ETo) is essential for planning of projects related to water resources. This article compares the results obtained from the available pan evaporation based equations to estimate ETo from pan evaporation (E-p) and proposes a new simplified methodology for estimation of ETo, which needs only the data of relative humidity (H). The resulting model is based upon the collected meteorological data of a selected study area i.e. Nagpur District in Maharashtra State, which lies in western plateau and hills region of India. In the proposed methodology, E-p rates are adjusted to the values expected for 50 % relative humidity. Then, the relationship between ETo and the adjusted E-p is established. The validation of the proposed new model has been carried out by comparing its results with the results obtained by the pan evaporation method, for the study area as well as for the data set of another area. This new model is found to be reasonably accurate for estimation of reference evapotranspiration for the study area and as such, is expected to be applicable to the river basins located in the regions having climatic conditions similar to that of the study area. Although, if the conditions are different then another site specific model can be developed by adopting the methodology proposed in this article.
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This paper addresses the theory and recommended control logic for an online cleaning procedure of a vertical continuous vacuum pan. The online cleaning procedure increases the massecuite temperature in the pan by increasing the he...
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This paper addresses the theory and recommended control logic for an online cleaning procedure of a vertical continuous vacuum pan. The online cleaning procedure increases the massecuite temperature in the pan by increasing the head space pressure, which results in the release of sugar build-up and re-establishes pan circulation. An International Society of Sugar Cane Technologists (ISSCT) Process Workshop held in South Africa in 2014 reported the use of an online cleaning program for continuous vacuum pans in South African mills. Wilmar Sugar conducted trials of this procedure during the 2015 crushing season on a vertical continuous high grade seed pan at Victoria Mill. The main objective of the project was to increase the period between continuous pan water boils that were regularly required to remove sugar crystal build-up inside the pan. The outcome from the project showed an improvement in this period from 7 to 14 days for the continuous high grade seed pan. No adverse impacts were noted and an improvement in product sugar quality was evident. The major benefit from the implementation of this cleaning procedure was the reduction in the number of pan water boils that had to be undertaken during the season.
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The most precise equation in order to estimate the evapotranspiration (ET) of crops is the Penman-Monteith (PM). However, the PM equation needs specific data that, in the majority of Mexico's irrigation districts, it is not availa...
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The most precise equation in order to estimate the evapotranspiration (ET) of crops is the Penman-Monteith (PM). However, the PM equation needs specific data that, in the majority of Mexico's irrigation districts, it is not available because there are few automated weather stations. For this reason, it is convenient to develop simple methods that allow to precise estimation of ET. A reliable way to estimate ET is by using the pan evaporation that, according to the revised literature, continues to be used nowadays. Investigators like to include its use in irrigation water management projects in various parts of the world. However, this method uses Kp from the FAO that is not calibrated in Mexico. The use of FAO Kp affects the precision of the results, since some variables like radiation, wind, temperature and relative humidity vary from place to place; therefore ET is under estimated or overestimated. This paper presents an original contribution across method to estimate "Kp pan evaporation and ETo monthly maps", using information from 60 weather observatories included in The Climate Normals (1941-1970) from Mexico, based on the PM method and the class A pan evaporation. Once the Kp values were obtained from each weather observatory, the Kringing method was used. This way, by interpolating data of the triad "latitude, longitude and Kp" and "latitude, longitude and ET", monthly normalized maps of Kp and ET were established for Mexico, except the upland areas (Sierra Madre Occidental and Sierra Madre Oriental), as well as other highland zones above 2700 meters over sea level, for the highest observatory is located in Toluca, State of Mexico (key 14-0039), at 2680 m over sea level.
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Motivation: We present the Pangenome Analysis Toolkit (PATO) designed to simultaneously analyze thousands of genomes using a desktop computer. The tool performs common tasks of pangenome analysis such as core-genome definition and...
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Motivation: We present the Pangenome Analysis Toolkit (PATO) designed to simultaneously analyze thousands of genomes using a desktop computer. The tool performs common tasks of pangenome analysis such as core-genome definition and accessory genome properties and includes new features that help characterize population structure, annotate pathogenic features and create gene sharedness networks. PATO has been developed in R to integrate with the large set of tools available for genetic, phylogenetic and statistical analysis in this environment. Results: PATO can perform the most demanding bioinformatic analyses in minutes with an accuracy comparable to state-of-the-art software but 20-30x times faster. PATO also integrates all the necessary functions for the complete analysis of the most common objectives in microbiology studies. Finally, PATO includes the necessary tools for visualizing the results and can be integrated with other analytical packages available in R.
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In this study daily evaporation rate from class A pan and reduced pan installed inside the glasshouse with a class A pan installed outside were compared. The results showed that the mean weekly ET_(0) value estimated by the class ...
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In this study daily evaporation rate from class A pan and reduced pan installed inside the glasshouse with a class A pan installed outside were compared. The results showed that the mean weekly ET_(0) value estimated by the class A pan installed outside and inside the glasshouse were 27.6 mm and 17.6 mm respectively, and 20.3 mm for the reduced pan. The ET_(0) in the glasshouse was found to be 64% of outdoor ET_(0). With regard to the comparisons between the weekly ET_(0) values estimated by the class A pan and reduced pan, both inside the glasshouse, coefficient of correlation was obtained 0.95 for the reduced pan method and with comparing between the weekly ET_(0) values estimated by the class A pan outside the glasshouse and those estimated by the different methods inside, coefficient of correlation was obtained 0.71 for the class A pan and 0.68 by the reduced pan.
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Estimates of the amount of genetic differentiation in humans among major geographic regions (e.g., Eastern Asia vs. Europe) from quantitative-genetic analyses of cranial measurements closely match those from classical- and molecul...
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Estimates of the amount of genetic differentiation in humans among major geographic regions (e.g., Eastern Asia vs. Europe) from quantitative-genetic analyses of cranial measurements closely match those from classical- and molecular-genetic markers. Typically, among-region differences account for ~10% of the total variation. This correspondence is generally interpreted as evidence for the importance of neutral evolutionary processes (e.g., genetic drift) in generating among-region differences in human cranial form, but it was initially surprising because human cranial diversity was frequently assumed to show a strong signature of natural selection. Is the human degree of similarity of cranial and DNA-sequence estimates of among-region genetic differentiation unusual? How do comparisons with other taxa illuminate the evolutionary processes underlying cranial diversification? Chimpanzees provide a useful starting point for placing the human results in a broader comparative context, because common chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) are the extant species most closely related to humans. To address these questions, I used 27 cranial measurements collected on a sample of 861 humans and 263 chimpanzees to estimate the amount of genetic differentiation between pairs of groups (between regions for humans and between species or subspecies for chimpanzees). Consistent with previous results, the human cranial estimates are quite similar to published DNA-sequence estimates. In contrast, the chimpanzee cranial estimates are much smaller than published DNA-sequence estimates. It appears that cranial differentiation has been limited in chimpanzees relative to humans.
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