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1.
Article Dans Chinois | WPRIM | ID: wpr-1024996

Résumé

【Objective】 To compare the desalination effects of five desalination methods and their effects on the components for human coagulation factor Ⅷ(FⅧ), and provide reference for selection of protein desalination methods. 【Methods】 Sephadex G-25 Medium gel, Fractogel EMD BioSEC gel, ultrafiltration, room temperature dialysis and 4℃ dialysis were used to desalt human FⅧ. The desalination effect was evaluated by the removal rate of Na +, citrate ion and glycine. FⅧ protein recovery, FⅧ activity (FⅧ∶C), VWF antigen (VWF∶Ag), VWF activity(VWF∶Ac), VWF polymers and SDS-PAGE analysis before and after desalination were compared to evaluate the effect of desalination on FⅧ components. 【Results】 In terms of desalination effect, the removal rate of Na+ was the lowest in ultrafiltration desalination, while that of Fractogel EMD BioSEC gel was the highest [(97.90±0.06) % vs (99.82±0.07) %]. Except that there was no statistical significance between Sephadex G-25 Medium gel desalination and Fractogel EMD BioSEC gel desalination (P=0.90), the removal rates of the other four methods were statistically significant. The removal rate of glycine was the lowest in ultrafiltration desalination, wihle that of Fractogel EMD BioSEC gel desalination was the highest [(95.78±0.42) % vs (99.81±0.08) %]. Significant difference in glycine removal was noticed in ultrafiltration desalination, but not among the other four desalination methods. There was no significant difference in the removal rate of citrate ions among the five methods (P=0.85). For the effect of FⅧ components, FⅧ∶C, VWF∶Ag, VWF∶Ac and protein recovery rates of ultrafiltration desalination were the highest, with (18.34±1.99) IU/mL, (11.81±0.33) IU/mL, (12.26±0.58) IU/mL and (97.13±1.37) %, respectively. There was no significant change in VWF∶Ac/VWF∶Ag before and after desalination by the five methods. SDS-PAGE and VWF polymer analysis showed that different desalination methods had no significant impact on protein composition. 【Conclusion】 Although different desalination methods had no significant effect on the composition of FⅧ protein, the desalination effect was different. Moreover, different desalination methods had significant effects on protein recovery, FⅧ∶C, VWF∶Ag and VWF∶Ac. The selection of desalination methods should be more considered during protein processing,

2.
Eng. sanit. ambient ; 25(1): 107-114, jan.-fev. 2020. tab, graf
Article Dans Portugais | LILACS-Express | LILACS | ID: biblio-1090122

Résumé

RESUMO Com a escassez da disponibilidade de água doce e o aumento da demanda de água no mundo e no Brasil, uma das alternativas são os sistemas de dessalinização de água, que removem os sais das águas salobra ou salgada. Este estudo teve como objetivo avaliar a eficiência de um sistema piloto de dessalinização de água salobra a qual foi obtida a partir da mistura de águas do mar e de rio até atingir concentração de sólidos dissolvidos totais (SDT) de 1.500 mg.L-1. O sistema piloto de dessalinização, com capacidade de 1,0 m3.h-1, é composto de ultrafiltração (UF) e abrandamento como pré-tratamento à osmose reversa (OR). Foram realizadas análises de qualidade da água na entrada e saída das unidades de tratamento relativas a SDT, condutividade elétrica, turbidez, pH, cor aparente, alcalinidade, dureza total, cálcio, magnésio, cloreto, sulfato e temperatura. Foram avaliadas a pressão osmótica, o fluxo de filtração e a taxa de recuperação de água no sistema de OR. Com os resultados obtidos, conclui-se que a eficiência de remoção de SDT e condutividade foi de 99%. A UF foi eficiente na remoção de turbidez, enquanto a OR apresentou maiores eficiências de remoção de sais. O sistema piloto de tratamento foi capaz de remover todos os parâmetros estudados. A taxa de recuperação na OR foi de 74,64%.


ABSTRACT Considering the shortage of fresh water availability and an increased demand for water in the world, including Brazil, one of the alternatives for water supply are water desalination systems, which remove salts from brackish or seawater. The objective of this study was to evaluate the efficiency of pilot water desalination system treating brackish water which was obtained mixing fresh water and seawater up to reach 1,500 mg L-1 of total dissolved solids (TDS) concentration. The pilot desalination plant with production capacity of 1.0 m3 h-1 is composed of ultrafiltration (UF) and softener working as a pre-treatment to reverse osmosis (RO). Experiments were performed to analyze some water quality parameters as TDS, electrical conductivity, turbidity, pH, apparent color, alkalinity, total hardness, calcium, magnesium, chlorides, sulfates, and temperature. Osmotic pressure, filtration flow and water recovery rate were also measured for the RO. Analyzing the result obtained, it can be concluded that the efficiency of TDS removal and conductivity were 99%. UF was efficient in removing turbidity, whereas RO reached higher salt removal efficiencies. The pilot plant system could remove all water quality parameters studied. Recovery rate in RO was 74.64%.

3.
Eng. sanit. ambient ; 24(5): 861-873, set.-out. 2019. graf
Article Dans Portugais | LILACS-Express | LILACS | ID: biblio-1056090

Résumé

RESUMO A falta de água é um problema que afeta muitas regiões do nosso planeta, especialmente ilhas e locais de clima muito seco. Especialistas dizem que essa situação irá se agravar e que, em 2025, cerca de 1,8 bilhão de pessoas sofrerão com essa escassez. Embora métodos tradicionais de dessalinização sejam alternativas bem conhecidas e implantadas para obtenção de água potável, eles não são sustentáveis ambientalmente, porque são geralmente supridos por combustíveis não renováveis, cuja queima intensifica o efeito estufa, trazendo desequilíbrios ao meio ambiente. Outra opção que vem sendo desenvolvida ao longo dos anos é a dessalinização por energia solar. Como se trata de uma forma de energia limpa, abundante e renovável, esse método já é muito indicado em regiões isoladas, de baixa e média demanda. Algumas técnicas são apresentadas neste trabalho, que foca o método de dessalinização por umidificação e desumidificação (DSUD). Essa técnica tem se mostrado a mais eficiente, devido ao seu reaproveitamento de energia. Há ainda muito o que melhorar para viabilizar a sua implantação em grande escala, principalmente em termos de produção de água, energia específica requerida e custo específico de produção de água. Entretanto, a DSUD já se mostrou uma técnica sustentável, promissora, de custo razoável e funcionamento simples. Dessa forma, os autores incentivam maiores investimentos em pesquisas no Brasil na área de dessalinização solar e aproveitamento dos rejeitos do processo, visando à produção de água purificada nas regiões brasileiras que têm deficiência em água potável.


ABSTRACT The lack of water is a problem that affects many regions in our planet, specially in very dry places and isles. Experts say that this situation will worsen, and that by 2025 about 1.8 billion people will suffer with water scarcity. Although traditional desalination methods are well-known and implemented alternatives to obtain fresh drinking water, they are not environmentally sustainable, because they are generally supplied by non-renewable fuels, whose combustion intensifies the greenhouse effect, causing disequilibrium to the environment. Another option that has been developed along the years is the desalination by solar energy. Since it is a clean, abundant and renewable type of energy, it is already a good option to isolated regions, whose demand is low or medium. Some technics are shown in this work, which focuses on the humidification-dehumidification desalination method. This technique has shown to be the most efficient one, due to its energy reuse. There is still a long way to go in order to make it viable in large scale, especially in terms of water production, specific energy requirement and specific cost of water production. However, solar desalination by humidification-dehumidification has proven to be a sustainable, promising technic which is reasonably costly and simple to operate. Therefore, the authors encourage more investments in researches in Brazil in the area of solar desalination and use of its rejects, aiming at the production of fresh water in Brazilian regions lacking it.

4.
Article Dans Anglais | WPRIM | ID: wpr-773409

Résumé

OBJECTIVE@#To explore the possible long-term health effects of the defoamer used in seawater desalination by sub-chronic toxicity testing.@*METHODS@#Blood analysis, internal organ assessment, and histopathological examination were carried out in rats exposed to low, medium, and high (0.5, 1.0, and 2.0 g/kg BW, respectively) doses of defoamer for 90 days through oral administration.@*RESULTS@#The high dose group showed decreased blood alanine aminotransferase and aspartate aminotransferase (P < 0.05). All doses resulted in a significant increase in albumin and decrease in globulin (P < 0.05). The direct bilirubin and indirect bilirubin were decreased in the medium and high dose groups (P < 0.05). All dose groups showed significant induction of alkaline phosphatase (P < 0.05). Pathological examination revealed a case of liver mononuclear cell infiltration in the medium dose group and three cases of liver congestion, steatosis of hepatic cells around the central vein, and punctate necrosis with multiple focal mononuclear cell infiltration in male rats administered the high dose. The No Observed Adverse Effect Level was 0.5 g/kg BW in rats, with albumin and total bilirubin as health effect indices.@*CONCLUSION@#Long-term defoamer exposure may cause liver injury but has no significant impact on renal function in rats. The effect on blood cells in female rats was more prominent than that in male rats.


Sujets)
Animaux , Femelle , Mâle , Administration par voie orale , Antimoussants , Toxicité , Analyse chimique du sang , Poids , Consommation alimentaire , Rat Wistar , Tests de toxicité subchronique
5.
Article Dans Anglais | IMSEAR | ID: sea-158116

Résumé

A systematic study has been carried out to explore the water quality index of ground water of various locations of Gulbarga city. Ten water samples from tube wells, open wells and hand pumps at various locations were collected using standard procedural methods and analyzed for pH, nitrate, turbidity, total hardness, alkalinity, fluoride, sulphate, sulphide, COD and DO. Biological examinations were extensively carried out on each sample using known standard methods. In this study overall water quality of Gulbarga city is very poor and unsuitable for drinking purposes. Present study recommends that the top priority should be given to water quality monitoring and indigenous technologies should be adopted to make water fit for drinking after treatment such as desalination and defluoridation.

6.
Braz. j. med. biol. res ; 43(3): 230-233, Mar. 2010. tab, mapas, graf
Article Dans Anglais | LILACS | ID: lil-539725

Résumé

Climatic changes threaten the planet. Most articles related to the subject present estimates of the disasters expected to occur, but few have proposed ways to deal with the impending menaces. One such threat is the global warming caused by the continuous increase in CO2 emissions leading to rising ocean levels due to the increasing temperatures of the polar regions. This threat is assumed to eventually cause the death of hundreds of millions of people. We propose to desalinize ocean water as a means to reduce the rise of ocean levels and to use this water for populations that need good quality potable water, precisely in the poorest regions of the planet. Technology is available in many countries to provide desalinated water at a justifiable cost considering the lives threatened both in coastal and desertified areas.


Sujets)
Humains , Polluants atmosphériques/toxicité , Dioxyde de carbone/toxicité , Catastrophes/prévention et contrôle , Surveillance de l'environnement , Réchauffement de la planète/prévention et contrôle , Alimentation en eau , Océans et mers , Mouvements de l'eau
7.
Article Dans Anglais | WPRIM | ID: wpr-96412

Résumé

When the concentration of sodium (Na+) in arterial plasma (P(Na)) declines sufficiently to inhibit the release of vasopressin, water will be excreted promptly when the vast majority of aquaporin 2 water channels (AQP2) have been removed from luminal membranes of late distal nephron segments. In this setting, the volume of filtrate delivered distally sets the upper limit on the magnitude of the water diuresis. Since there is an unknown volume of water reabsorbed in the late distal nephron, our objective was to provide a quantitative assessment of this parameter. Accordingly, rats were given a large oral water load, while minimizing non-osmotic stimuli for the release of vasopressin. The composition of plasma and urine were measured. The renal papilla was excised during the water diuresis to assess the osmotic driving force for water reabsorption in the inner medullary collecting duct. During water diuresis, the concentration of creatinine in the urine was 13-fold higher than in plasma, which implies that ~8% of filtered water was excreted. The papillary interstitial osmolality was 600 mOsm/L > the urine osmolality. Since 17% of filtered water is delivered to the earliest distal convoluted tubule micropuncture site, we conclude that half of the water delivered to the late distal nephron is reabsorbed downstream during water diuresis. The enormous osmotic driving force for the reabsorption of water in the inner medullary collecting duct may play a role in this reabsorption of water. Possible clinical implications are illustrated in the discussion of a case example.


Sujets)
Animaux , Rats , Aquaporine-2 , Aquaporines , Créatinine , Diurèse , Membranes , Néphrons , Concentration osmolaire , Perméabilité , Phénobarbital , Plasma sanguin , Polyurie , Ponctions , Sodium , Vasopressines , Eau
8.
Article Dans Chinois | WPRIM | ID: wpr-676854

Résumé

The process mechanism and current application status of boron removal in reverse osmosis(RO)desalination were introduced.The characteristic and proper application range of eachboron removal process was summarized.Also,the running conditions of two practical desalination cases were analyzed and compared.Eventually,the future of application and the research direction of boron removal process in RO desalination were prospected.

9.
China Pharmacy ; (12)2007.
Article Dans Chinois | WPRIM | ID: wpr-531624

Résumé

OBJECTIVE:To study the extracting and purifying process of Achyranthes bidentata polysaccharides(ABP). METHODS:Crude polysaccharide was obtained by extracting ABP raw material by water decocting method.The Crude polysaccharide was purified(deproteinization,desalination and alcohol precipitation) to obtain ABP.The content of total polysaccharide was taken as an evaluation index to optimize the optimum conditions of extracting and purifying.RESULTS: The optimum water decoction conditions were as follows:ABP raw material was extracted three times (2 h/time) by adding 10 times amount of water.As for the deproteinization process,TCA(trichloracetic acid) method was superior to Sevage method and tannic acid method;Desalination by molecular sieve was superior to that by dialysis method; and alcohol precipitation was performed with 80% alcohol.CONCLUSION:ABP can be prepared by water decoction,deproteinization,desalination and alcohol precipitation of its raw material.

10.
Article Dans Chinois | WPRIM | ID: wpr-592948

Résumé

Objective To develop a water station that can be loaded to a ship and supply freshwater. Methods The water station comprises the reverse osmosis seawater desalination device, pressure water tank, high pressure water pump, etc, with 40-feet international standard containers as the carrier. Results The water station can produce 80 t freshwater daily, and the quality of produced water conforms to the standards of the state and army for drinking water quality. Conclusion The water station, which has highly-compaction, strong-mobility, excellent-adaptability and high-automaticity, fits for a ship.

11.
Article Dans Chinois | WPRIM | ID: wpr-536259

Résumé

Objective To assess the sanitary quality of finished water produced by seawater desalination plant.Methods Using reverse osmosis for seawater desalination,the microbiological indexes,the levels of chloride and the pH values of finished water after seawater desalination were determined and then were assessed based on the National Method for Determination of Drinking Water(GB 5750-1985).Results After seawater desalination,the level of fluoride in finished water was 426 mg/L,the total count of bacteria of 3 finished water samples among 9 samples exceeded the standedard(350,300,4016/L),the pH valuer were qualified on the whole,except one lower value of 5.74 and a higher value of 8.94.Conclusicn After the treatment by seawater desalination system,the level of residual chloride in finished water was higher which approached the related highest limit ruled by National Sanitary Standard for Drinking Water,the microbiological indexes and pH values of finished water were unstable.

12.
Article Dans Chinois | WPRIM | ID: wpr-594403

Résumé

Objective To study the operating parameters of the field seawater desalination reverse osmosis device by RO process and analyze quality of the product water.Methods In pressure of 4.90~6.37 MPa,the influence of operating pressure on salt rejection and water flux is researched to determine the best parameter.Except some conventional item test,the water quality analysis also includes BOD,COD,TOC,fluorescence spectra,ultraviolet spectra and chromatography of ions analysis.Results Operating pressure of 5.88 ~6.37 MPa,the water flux reaches 18 ~22 L/h and the ratio of desalinization exceeds 97.4%.The device has an organic contaminant elimination ratio higher than 95% and ion desalination ratio also more than 96%.The fundamental index is consistent with drinking water sanitary standard.Conclusion The field seawater desalination reverse osmosis device by RO process can effectively wipe off bacteria and contaminant of water and also can reduce salt salinity in untreated water to produce pure water for drinking.

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