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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Aquamati

Dávila Valle, Melissa Paola, Rondon Medina, Eduardo Francisco, Navarro Tillit, Daniela Paola, Cachay Purizaga, Mario Andre, Chura Ovalle, Luis Alberto 03 July 2019 (has links)
En este proyecto se desarrolla un nuevo producto que se lanzará al mercado de aguas Premium. En este abstracto se podrá observar el procedimiento que se desarrolló para poder analizar correctamente si el proyecto es rentable o no. Nuestro proyecto tiene como finalidad introducir al mercado un producto innovador, el cual es Aquamati; un agua ozonizada, la cual tiene diferentes beneficios con respecto a las aguas que comúnmente encontramos en el mercado. Este es un producto eco amigable, debido a que su presentación es en botella de vidrio reutilizable, y beneficioso para la salud, ya que el ozono es un purificador natural. En este trabajo podrán observar todas las etapas en las que desarrollamos ideas, entrevistamos a posibles consumidores, establecimos hipótesis de mercado, hicimos focus group en el que se evaluó el sabor y la imagen del producto y finalmente establecimos estrategias para poder insertar nuestro producto y hacerlo competitivo. Nuestra agua va dirigida a personas de nivel socioeconómico A y B entre 18 a 50 años que viven en Lima, con tendencia de compra de productos que incentiven la vida saludable y un perfil sofisticado. Finalmente, en el trabajo se visualiza toda de planeamiento de actividades como las de Recursos Humanos, Marketing, Responsabilidad Social, la parte del financiamiento y la parte contable de nuestro proyecto en el cual se ve la viabilidad del negocio. / This project entails the development of a new product that will be launched to the bottled water market. In this abstract, We'll show the process developed to correctly analyze if the project was profitable or not. Our project's goal is to introduce to the market a novel product, Aquamati is ozonized water, which has several benefits that regular bottled water in the market do not, It's an eco-friendly product, being possible to reuse its glass bottle, and ozone being a natural purifier, it offers several health benefits. In this document, you will see all the phases in which we developed the core ideas, interviewed potential consumers, established market hypothesis, ran focus groups in which the product's flavor and image were evaluated, and finally designed strategies to insert our product in a way that makes it competitive. Our water is targeted towards consumers from socioeconomic status A and B, and between ages of 18 and 50 years old, that reside in Lima and have a tendency to buy products that incentivize a healthy life and a sophisticated life style. Finally, in the document you'll be able to see the planning of activities such as: human resources, marketing, social responsibility, finances, and accounting, which show the viability of the business. / Trabajo de investigación
82

Optimization of reverse osmosis membrane networks

Maskan, Fazilet, Chemical Engineering & Industrial Chemistry, UNSW January 2000 (has links)
The optimization of a reverse osmosis (RO) system includes optimization of the design of the individual membrane modules, the system structure and the operating conditions of the system. Most previous studies considered either the optimal design of individual modules only or optimization of system structure and operating conditions for fixed module dimensions. This thesis developed a method to simultaneously optimize the module dimensions, system structure and operating conditions. The method comprised rules for generating a general superstructure for an RO system given the number of modules along with rules for generating technically and mathematically feasible sub-structures. The superstructure was based on maximum connectivity between unit operations. A connectivity matrix was used to represent the superstructure. The matrix was useful for checking sub-structure's feasibility and deriving a model for the sub-structure's optimization, comprising the minimum number of variables and constraints which minimized computational time and increased accuracy. For optimization, a nonlinear objective function of the annualized profit of the RO system was formulated, consisting of the revenue obtained from permeate sales, capital costs of the unit operations and operating costs for the system. It was found that RO system optimization is a nonconvex optimization problem. The most effective optimization procedure involved a combination of evolutionary computation, which was good for locating the global optimum, and a gradient-based method, which was superior in finding the exact optimum. Small population size, adaptive mutation rate and steady state replacement were the most efficient parameter settings for the evolutionary computation. Optimal design of two-stage RO systems with and without energy recovery, bypass and recycle streams was studied. Dimensions of predicted optimal modules approached those of current commercial modules but with much shorter feed channels. The mathematical optimum also had higher operating pressures. The optimum system structure was a series arrangement with different module dimensions in each stage. A sensitivity analysis showed that trends in the optimal design were similar when unit costs changed. An investigation of the scalability of the method for a three-stage RO system revealed several weaknesses. These are probably surmountable with the addition of more RO system specific knowledge.
83

Membrane filtration : fouling and cleaning in forward osmosis, reverse osmosis, and ultrafiltration membranes

Siddiqui, Farrukh Arsalan January 2017 (has links)
A comparison of fouling in osmotically driven processes with that in pressure driven processes is the main focus of the thesis. Forward osmosis (FO) and reverse osmosis (RO) have received considerable attention for water treatment and seawater desalination. This research compared the nature of fouling in FO mode with that in RO starting with the same initial flux in connection with cleaning effects and then comparing to those in ultrafiltration membranes. In all cases, with cleaning as an integral part, the extent of fouling reversibility, and the question whether a critical flux could be determined were examined. The work during the first phase (undertaken at Oxford) quantified the removal of reversible fouling through rinsing by cold and hot water for a range of concentrations using the foulants dextran and carboxymethyl cellulose. The flux-TMP relationship was conventionally compared to that of the clean water flux. The later phase (at Singapore) compared the fouling in FO and RO by alginate in terms of multiple parameters using cellulose tri acetate (CTA) and thin film composite (TFC) membranes. Silica and alginate were selected as model foulants. Whilst experimental water flux profiles in the present study did not exhibit significant differences in trend between FO and RO fouling, foulant resistance for FO was found to be increasingly greater than for RO with the progression of the fouling tests. This was further corroborated by membrane autopsies post fouling tests; both foulant mass deposition density and specific foulant resistance for FO were greater than for RO. The analysis clearly revealed that FO is essentially more prone to fouling than RO which was presumably due to less flux decline in FO (or greater average flux) as compared to that in RO in result of ICP-self compensation effect which is opposite to the prevailing claim in the literature. Additionally, the present study did not find evidence that hydraulic pressure in RO has a role in foulant layer compaction. FO membrane fouling by real waters was the focus of the final phase of the research at SMTC. Pilot scale FO experiments were conducted on spiral wound CTA membrane with treated waste water obtained from a NEWater factory (Singapore) as the feed. In the second stage, experiments were repeated at bench scale with membrane coupons taken from the spiral wound membranes used earlier. The key finding was that the mass transfer coefficients in the Spiral-Wound module were around 50% lower than the corresponding values in the flat sheet unit and this severely limited the fluxes. The reason could be attributed to strong internal concentration polarisation in the former, where tightly wound spacers act to increase the structural parameter.
84

Vasopressin production in the salt loaded rat

Lawson, L. J. January 1988 (has links)
No description available.
85

Aspects of osmoregulation in an intertidal shore crab, Hemigrapsus nudus (Dana)

Alspach, George Samuel Jr 12 May 1967 (has links)
Graduation date: 1967
86

New development of theory and application in capillary electrophoresis : extended dissociation model for predicting electroosmotic mobility, correction of electrokinetic sampling bias and enantiomeric separations /

Zhou, Marilyn Xiaohong. January 2004 (has links)
Thesis (Ph. D.)--Drexel University, 2004. / Includes abstract and vita. Includes bibliographical references (leaves 198-202).
87

Dehumidification effect by coupling an electroosmotic material with a desiccant interface

Mina, Ehab Mouris. January 2004 (has links)
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2004. / Adviser: Ty A. Newell. Includes bibliographical references.
88

The use of reverse osmosis and ultrafiltration in the food industry

Fenton-May, Roualeyn Iain, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1971. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
89

[en] THE STUDY OF ELECTRO-OSMOSIS IN RESIDUAL SOILS: DEVELOPMENT OF TEST EQUIPMENT AND METHODOLOGY / [pt] ESTUDO DA ELETRO-OSMOSE EM SOLOS RESIDUAIS DESENVOLVIMENTO DE EQUIPAMENTO E METODOLOGIA DE ENSAIO

BIDKAR MANUEL MONTERROSO RIVAS 09 September 2002 (has links)
[pt] A presente dissertação apresenta o estudo da eletro- osmose em um solo residual gnaissico em ambiente laboratorial. O foco do trabalho foi direcionado ao desenvolvimento de equipamento e metodologia de ensaio. Duas células foram desenvolvidas, uma para amostras indeformadas e outra para amostras reconstituídas em laboratório.Os resultados do programa experimental não contrastaram muito com os disponíveis na literatura técnica. Observou-se que o fluxo eletro-osmótico é proporcional ao gradiente elétrico aplicado e que apresentava um comportamento errático durante o decorrer do ensaio,possivelmente devido às reações causadas pela eletrocinese. A variação no teor de umidade através dos corpos de provas foram ínfimas. Um fato curioso foi a indepedência dos parâmetros que avaliam a eficiência eletro-osmótica em relação ao gradiente elétrico aplicado.Em relação ao consumo energético, verificou-se que o mesmo é maior durante os instantes iniciais do ensaio e tende a se estabilizar com o passar do tempo. Observou-se ainda, uma relação direta com o gradiente elétrico aplicado. Para fins de projeto, o consumo enérgético pode ser estimado como US$ 0,30 por kW.h/m3. / [en] The present dissertation presents a laboratory study of electro-osmosis in a residual soil from gneiss. The objective of this study was to develop test equipment and methodology. Two different cells were constructed,one for natural and the other for reconstituted material. The experimental results are consistent with technical literature values. It was observed that the electro-osmotic flow is proportional to the magnitude of the eletrical potential gradient and shoewd a some what erratic behaviour during the test, which could be due to the physical- chemical reactions through the soil caused by electrolysis. The variation of water content in the specimens was minimal. One curious fact was that the electroosmotic efficiency coefficient, which evaluates the electroosmotic efficiency , turned out to be independent from the eletrical potential gradient. The power expenditure was greater during the initial stages of the tests and tended to stabilise over the remaining time.It was observed a direct relation between the power expenditure and the eletrical potential gradient. For design purposes, the current cost of energy expenditure could be assumed as U21730 0,30 per KW.h/m³. There is a little variation in the temperature of electrolytes during tests. It was also observed that eletroosmotic flow can be improved by acidification of the solution.
90

Osmotic and ionic regulation in embryos, alevins and fry of the five species of Pacific salmon

Weisbart, Melvin January 1967 (has links)
The major purpose of this study was to examine the physiological basis of the differences in the early life histories of pink Oncorhynchus gorbuscha, chum O. keta, coho O. kisutch, chinook O. tshawytscha and sockeye O. nerka. To this end, the following working hypotheses were tested: (i) the embryo, alevin and fry of pink and chum salmon are euryhaline, whereas the same life stages of coho, chinook and sockeye are stenohaline and (ii) the euryhalinity of pink and chum is due not to high tissue tolerance but to their ability to regulate the osmotic and ionic concentrations in their blood, whereas the stenohalinity of coho, chinook and sockeye stems from their inability to osmoregulate and ion regulate. The results did not completely support these hypotheses. The LD₅₀ values and the osmoregulatory data obtained from embryos indicated that pink and chum are not euryhaline as hypothesized but like coho, chinook and sockeye embryos are stenohaline. However, pink and chum embryos showed significantly greater salinity resistance and osmoregulatory ability than embryos of the other species. The data obtained from alevins also did not support the working hypothesis for alevins of all five species were found to be stenohaline. But, as in the case for embryos, pink and chum alevins showed greater salinity resistance and osmoregulatory abilities than coho and sockeye alevins. This ability of pink and chum was correlated with better ionic regulation of sodium and chloride. Although chinook alevins survived considerably longer in 31.8 °/oo sea water than coho and sockeye alevins , their ability to osmoregulate and ion regulatewas not very different from that of coho and sockeye alevins. It was concluded, therefore, that the greater salinity resistance of chinook alevins was due to high tissue tolerance. Contrary to the results with embryos and alevins, the data obtained from fry supported the working hypotheses. The results showed that pink and chum were euryhaline and that this condition was due to their ability to osmoregulate and control the levels of sodium and chloride in the blood. Coho, chinook and sockeye fry were found to be stenohaline and were unable to regulate the osmotic and ionic concentrations in their blood. As in the case of alevins, chinook fry, due to higher tissue tolerance, manifested greater salinity resistance than coho and sockeye. When the data for all species of embryos and fry were grouped and compared to the alevins taken as a group, the LD₅₀ values of embryos and fry were found to be significantly greater than those of the alevins . The blood osmotic concentrations of embryos and fry exposed for the same duration in 31.8 °/oo sea water were significantly lower than the blood osmotic concentrations for alevins. It was included, therefore, that embryos and fry have greater salinity resistance than alevins because of the greater osmoregulatory ability of embryos and fry. On the basis of these results as well as information obtained from the literature, speculations were made on the phylogenetic relations within the genus Oncorhynchus. / Science, Faculty of / Zoology, Department of / Graduate

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