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1.
J Water Health ; 13(2): 489-99, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26042980

RESUMO

In view of green developments in water treatment, plant-based flocculants have become the focus due to their safety, degradation and renewable properties. In addition, cost and energy-saving processes are preferable. In this study, malva nut gum (MNG), a new plant-based flocculant, and its composite with Fe in water treatment using single mode mixing are demonstrated. The result presents a simplified extraction of the MNG process. MNG has a high molecular weight of 2.3 × 105 kDa and a high negative charge of -58.7 mV. From the results, it is a strong anionic flocculant. Moreover, it is observed to have a branch-like surface structure. Therefore, it conforms to the surface of particles well and exhibits good performance in water treatment. In water treatment, the Fe-MNG composite treats water at pH 3.01 and requires a low concentration of Fe and MNG of 0.08 and 0.06 mg/L, respectively, when added to the system. It is concluded that for a single-stage flocculation process, physico-chemical properties such as molecular weight, charge of polymer, surface morphology, pH, concentration of cation and concentration of biopolymeric flocculant affect the flocculating performance.


Assuntos
Malvaceae/química , Resinas Vegetais/química , Sementes/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Floculação , Ferro/química , Nefelometria e Turbidimetria , Reprodutibilidade dos Testes
2.
J Environ Manage ; 122: 121-9, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23570974

RESUMO

The ability of aluminum coagulant extracted from red earth to treat Terasil Red R (disperse) and Cibacron Red R (reactive) synthetic dye wastewater was studied. The effects of extractant concentration, soil-to-volume of extractant ratio, and the types of extracting agents (NaOH vs. KCl) on the concentration of aluminum extracted were also investigated. In addition, the efficiency of extracted aluminum was compared with aluminum sulfate, in terms of its capability to reduce the chemical oxygen demand (COD) and to remove synthetic color. Factorial design was applied to determine the effect of selected factors on the amount of aluminum extracted from red earth (i.e., pH, dose of coagulant, type of coagulant on COD reduction, and color removal). It was found that only selected factors exhibited a significant effect on the amount of aluminum extracted from red earth. It was also determined that all factors and their interactions exhibited a significant effect on COD reduction and color removal when applying the extracted aluminum in a standard coagulation process. The results were also compared to aluminum sulfate. Furthermore, NaOH was found to be a better extractant of aluminum in red earth than KCl. Therefore, the best extracting conditions for both extractants were as follows: 2 M NaOH and in a 1:5 (soil/volume of extractant) ratio; 1 M KCl and 1:5 ratio. In treating synthetic dye wastewater, the extracted coagulant showed comparable treatment efficiency to the commercial coagulant. The extracted coagulant was able to reduce the COD of the dispersed dye by 85% and to remove 99% of the color of the dispersed dye, whereas the commercial coagulant reduced 90% of the COD and removed 99% of the color of the dispersed dye. Additionally, the extracted coagulant was able to reduce the COD of the reactive dye by 73% and to remove 99% of the color of the reactive dye. However, the commercial coagulant managed to reduce the COD of the reactive dye by 94% and to remove 96% of the color for the reactive dye.


Assuntos
Alumínio/química , Corantes/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
3.
Theor Appl Climatol ; 152(1-2): 801-812, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37016660

RESUMO

Different health management strategies may need to be implemented in different regions to cope with diseases. The current work aims to evaluate the relationship between air quality parameters and the number of new COVID-19 cases in two different geographical locations, namely Western Anatolia and Western Black Sea in Turkey. Principal component analysis (PCA) and regression model were utilized to describe the effect of environmental parameters (air quality and meteorological parameters) on the number of new COVID-19 cases. A big difference in the mean values for all air quality parameters has appeared between the two areas. Two regression models were developed and showed a significant relationship between the number of new cases and the selected environmental parameters. The results showed that wind speed, SO2, CO, NOX, and O3 are not influential variable and does not affect the number of new cases of COVID-19 in the Western Black Sea area, while only wind speed, SO2, CO, NOX, and O3 are influential parameters on the number of new cases in Western Anatolia. Although the environmental parameters behave differently in each region, these results revealed that the relationship between the air quality parameters and the number of new cases is significant.

4.
Int J Food Sci Nutr ; 62(4): 410-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21306189

RESUMO

Yellow alkaline noodles (YAN) prepared by partial substitution of wheat flour with soy protein isolate and treated with microbial transglutaminase (MTG) and ribose were investigated during cooking. Cooking caused an increase in lightness but a decrease in redness and yellowness, pH, tensile strength and elasticity values of noodles. The extents of these changes were influenced by formulation and cross-linking treatments. The pH and lightness for YAN-ribose were lowest but the yellowness and redness were the highest whilst the tensile strength and elasticity values remained moderate. For YAN-MTG, the color and pH values were moderate, but tensile strength and elasticity values were the highest. YAN prepared with both cross-linking agents had physical values between YAN-ribose and YAN-MTG. Although certain sensory parameters showed differences in score, the overall acceptability of all 10-min-cooked YAN was similar. It is possible to employ cross-linking agents to improve physical properties of cooked YAN.


Assuntos
Culinária , Proteínas Alimentares , Farinha , Análise de Alimentos , Glycine max/química , Proteínas de Soja , Triticum , Cor , Reagentes de Ligações Cruzadas , Elasticidade , Manipulação de Alimentos/métodos , Humanos , Concentração de Íons de Hidrogênio , Ribose , Proteínas de Soja/isolamento & purificação , Resistência à Tração , Transglutaminases
5.
Data Brief ; 34: 106685, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33409347

RESUMO

This article provides data regarding the performance of zinc sulphate as a coagulant for treating rubber industry wastewater. The effect of four factors on removal efficiency of nine parameters is investigated, namely: pH, mixing speed, dosage of coagulant (zinc sulphate) and retention time. Response surface methodology was used to investigate the effect of selected variables. The data obtained from face centered composite design (FCCD) were analyzed by using analysis of variance (ANOVA) and regression model to find the optimum operating conditions for the selected factors.

6.
Polymers (Basel) ; 13(18)2021 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-34578081

RESUMO

In this study, acrylonitrile butadiene styrene (ABS)/talc/graphene oxide/SEBS-g-MAH (ABS/Talc/GO/SEBS-g-MAH) and acrylonitrile butadiene styrene/graphene oxide/SEBS-g-MAH (ABS/GO/SEBS-g-MAH) composites were isolated with varying graphene oxide (0.5 to 2.0 phr) as a filler and SEBS-g-MAH as a compatibilizer (4 to 8 phr), with an ABS:talc ratio of 90:10 by percentage. The influences of graphene oxide and SEBS-g-MAH loading in ABS/talc composites were determined on the mechanical and thermal properties of the composites. It was found that the incorporation of talc reduces the stiffness of composites. The analyses of mechanical and thermal properties of composites revealed that the inclusion of graphene oxide as a filler and SEBS-g-MAH as a compatibilizer in the ABS polymer matrix significantly improved the mechanical and thermal properties. ABS/talc was prepared through melt mixing to study the fusion characteristic. The mechanical properties showed an increase of 30%, 15%, and 90% in tensile strength (TS), flexural strength (FS), and flexural modulus (FM), respectively. The impact strength (IS) resulted in comparable properties to ABS, and it was better than the ABS/talc composite due to the influence of talc in the composite that stiffens and reduces the extensibility of plastic. The incorporation of GO and SEBS-g-MA also shows a relatively higher thermal stability in both composites with and without talc. The finding of the present study reveals that the graphene oxide and SEBS-g-MAH could be utilized as a filler and a compatibilizer in ABS/talc composites to enhance the thermo-mechanical stability because of the superior interfacial adhesion between the matrix and filler.

7.
Data Brief ; 30: 105414, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32258278

RESUMO

Data on the mineral composition and content of one heavy metal measured in three different fruit flours prepared from ripe and unripe fruits (pulp and peel) are presented. The mineral composition (sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), zinc (Zn), copper (Cu), iron (Fe) and manganese (Mn)) and content of one heavy metal (lead (Pb)) of the flours were analyzed by atomic absorption spectrophotometry. The analysis showed that the data can be used for differentiation between different fruits and stages of ripeness, as revealed by discriminant analysis and cluster analysis. The data provided can be used by researchers and scientists in the differentiation of fruits based on major and minor mineral elements.

8.
Int J Food Sci Nutr ; 60 Suppl 4: 116-25, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19115121

RESUMO

Major (sodium, potassium, calcium, magnesium) and minor elements (iron, copper, zinc, manganese) and one heavy metal (lead) of Cavendish banana flour and Dream banana flour were determined, and data were analyzed using multivariate statistical techniques of factor analysis and discriminant analysis. Factor analysis yielded four factors explaining more than 81% of the total variance: the first factor explained 28.73%, comprising magnesium, sodium, and iron; the second factor explained 21.47%, comprising only manganese and copper; the third factor explained 15.66%, comprising zinc and lead; while the fourth factor explained 15.50%, comprising potassium. Discriminant analysis showed that magnesium and sodium exhibited a strong contribution in discriminating the two types of banana flour, affording 100% correct assignation. This study presents the usefulness of multivariate statistical techniques for analysis and interpretation of complex mineral content data from banana flour of different varieties.


Assuntos
Manipulação de Alimentos , Frutas/química , Minerais/análise , Musa/química , Cálcio da Dieta/análise , Cobre/análise , Ferro da Dieta/análise , Chumbo/análise , Magnésio/análise , Manganês/análise , Análise Multivariada , Potássio na Dieta/análise , Sódio na Dieta/análise , Especificidade da Espécie , Estatística como Assunto , Zinco/análise
9.
Int J Food Sci Nutr ; 60 Suppl 4: 317-25, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19757247

RESUMO

Flour prepared from green and ripe Cavendish and Dream banana fruits were assessed for total starch, digestible starch, resistant starch, total dietary fiber, soluble dietary fiber and insoluble dietary fiber. Principle component analysis identified only one component responsible for explaining 83.83% of the total variance in the starch and dietary fiber components data to indicate that ripe banana flour had different characteristics from the green. Cluster analysis applied on similar data obtained two statistically significant clusters of green and ripe banana to indicate difference in behaviors according to the stages of ripeness. In conclusion, starch and dietary fiber components could be used to discriminate between flour prepared from fruits of different stage of ripeness. Results are also suggestive of the potential of green as well as the ripe banana flour as functional ingredients in food.


Assuntos
Fibras na Dieta/análise , Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Frutas/química , Frutas/crescimento & desenvolvimento , Musa/química , Amido/análise , Análise por Conglomerados , Carboidratos da Dieta/análise , Gorduras na Dieta/análise , Proteínas Alimentares/análise , Alimento Funcional/análise , Especificidade de Órgãos , Análise de Componente Principal , Solubilidade , Especificidade da Espécie , Amido/metabolismo , Água/análise
10.
Int J Food Sci Nutr ; 60 Suppl 4: 326-40, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19757248

RESUMO

The present study describes the utilization of banana--Cavendish (Musa acuminata L., cv cavendshii) and Dream (Musa acuminata colla. AAA, cv 'Berangan')--pulp and peel flours as functional ingredients in yellow alkaline noodles. Noodles were prepared by partial substitution of wheat flour with ripe banana pulp or peel flours. In most cases, the starch hydrolysis index, predicted glycaemic index (pGI) and physicochemical properties of cooked noodles were affected by banana flour addition. In general, the pGI values of cooked noodles were in the order; banana peel noodles < banana pulp noodles < control noodles. Since the peel flour was higher in total dietary fibre but lower in resistant starch contents than the pulp flour, the low pGI of banana peel noodles was mainly due to its high dietary fibre content. In conclusion, banana pulp and peel flour could be useful for controlling starch hydrolysis of yellow noodles, even though some physicochemical properties of the noodles were altered.


Assuntos
Digestão , Frutas/química , Alimento Funcional/análise , Musa/química , Amido/análise , Amido/metabolismo , Fenômenos Químicos , Cor , Culinária/métodos , Fibras na Dieta/análise , Manipulação de Alimentos , Frutas/crescimento & desenvolvimento , Glucose/metabolismo , Índice Glicêmico , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Mastigação , Fenômenos Mecânicos , Especificidade de Órgãos , alfa-Amilases Pancreáticas/metabolismo , Pepsina A/metabolismo , Solubilidade , Especificidade da Espécie , Fatores de Tempo
11.
Water Sci Technol ; 60(3): 771-81, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19657173

RESUMO

The performance of pectin in turbidity reduction and the optimum condition were determined using Response Surface Methodology (RSM). The effect of pH, cation's concentration, and pectin's dosage on flocculating activity and turbidity reduction was investigated at three levels and optimized by using Box-Behnken Design (BBD). Coagulation and flocculation process were assessed with a standard jar test procedure with rapid and slow mixing of a kaolin suspension (aluminium silicate), at 150 rpm and 30 rpm, respectively, in which a cation e.g. Al(3+), acts as coagulant, and pectin acts as the flocculant. In this research, all factors exhibited significant effect on flocculating activity and turbidity reduction. The experimental data and model predictions well agreed. From the 3D response surface graph, maximum flocculating activity and turbidity reduction are in the region of pH greater than 3, cation concentration greater than 0.5 mM, and pectin dosage greater than 20 mg/L, using synthetic turbid wastewater within the range. The flocculating activity for pectin and turbidity reduction in wastewater is at 99%.


Assuntos
Biopolímeros/química , Caulim/química , Pectinas/química , Purificação da Água/métodos , Análise de Variância , Biodegradação Ambiental , Cátions/química , Floculação , Concentração de Íons de Hidrogênio , Modelos Teóricos , Nefelometria e Turbidimetria , Oxirredução , Reprodutibilidade dos Testes , Propriedades de Superfície , Viscosidade
12.
Environ Monit Assess ; 153(1-4): 179-85, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18504644

RESUMO

Statistical analysis of heavy metal concentrations in sediment was studied to understand the interrelationship between different parameters and also to identify probable source component in order to explain the pollution status of selected estuaries. Concentrations of heavy metals (Cu, Zn, Cd, Fe, Pb, Cr, Hg and Mn) were analyzed in sediments from Juru and Jejawi Estuaries in Malaysia with ten sampling points of each estuary. The results of multivariate statistical techniques showed that the two regions have different characteristics in terms of heavy metals selected and indicates that each region receives pollution from different sources. The results also showed that Fe, Mn, Cd, Hg, and Cu are responsible for large spatial variations explaining 51.15% of the total variance, whilst Zn and Pb explain only 18.93 of the total variance. This study illustrates the usefulness of multivariate statistical techniques for evaluation and interpretation of large complex data sets to get better information about the heavy metal concentrations and design of monitoring network.


Assuntos
Poluentes Ambientais/análise , Sedimentos Geológicos/análise , Metais Pesados/análise , Cádmio/análise , Cromo/análise , Cobre/análise , Ferro/análise , Malásia , Manganês/análise , Mercúrio/análise , Zinco/análise
13.
Artigo em Inglês | MEDLINE | ID: mdl-31200470

RESUMO

The present study reports mathematical modelling of palm oil mill effluent and palm-pressed fiber mixtures (0% to 100%) during vermicomposting process. The effects of different mixtures with respect to pH, C:N ratio and earthworms have been optimized using the modelling parameters. The results of analysis of variance have established effect of different mixtures of palm oil mill effluent plus palm press fiber and time, under selected physicochemical responses (pH, C:N ratio and earthworm numbers). Among all mixtures, 60% mixture was achieved optimal growth at pH 7.1 using 16.29 C:N ratio in 15 days of vermicomposting. The relationship between responses, time and different palm oil mill waste mixtures have been summarized in terms of regression models. The obtained results of mathematical modeling suggest that these findings have potential to serve a platform for further studies in terms of kinetic behavior and degradation of the biowastes via vermicomposting.


Assuntos
Compostagem , Resíduos Industriais , Modelos Teóricos , Oligoquetos/metabolismo , Óleo de Palmeira , Animais , Biomassa
14.
Data Brief ; 24: 103894, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31011604

RESUMO

This article presents data relating to the changes in absorbance of glucose during the acid hydrolysis of sugarcane bagasse using sulphuric acid. This dataset also contains the moisture content, volatile matter, and fixed carbon of the sugarcane bagasse. The results of the analysis of variance (ANOVA) and the interaction plots between reaction time, temperature, and ratio are also presented. The data revealed that absorbance of glucose is increasing by increasing the temperature and time. Moreover, the best ratio for the highest absorbance of glucose was achieved at 1:20.

15.
Polymers (Basel) ; 11(8)2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31416151

RESUMO

In this study, tannin-based natural coagulant was used to treat stabilized landfill leachate. Tannin modified with amino group was utilized for the treatment process. Central composite design (CCD) was used to investigate and optimize the effect of tannin dosage and pH on four responses. The treatment efficiency was evaluated based on the removal of four selected (responses) parameters; namely, chemical oxygen demand (COD), color, NH3-N and total suspended solids (TSS). The optimum removal efficiency for COD, TSS, NH3-N and color was obtained using a tannin dosage of 0.73 g at a pH of 6. Moreover, the removal efficiency for selected heavy metals from leachate; namely, iron (Fe2+), zinc (Zn2+), copper (Cu2+), chromium (Cr2+), cadmium (Cd2+), lead (Pb2+), arsenic (As3+), and cobalt (Co2+) was also investigated. The results for removal efficiency for COD, TSS, NH3-N, and color were 53.50%, 60.26%, and 91.39%, respectively. The removal of selected heavy metals from leachate for Fe2+, Zn2+, Cu2+, Cr2+, Cd2+, Pb2+, As3+ and cobalt Co2+ were 89.76%, 94.61%, 94.15%, 89.94%, 17.26%, 93.78%, 86.43% and 84.19%, respectively. The results demonstrate that tannin-based natural coagulant could effectively remove organic compounds and heavy metals from stabilized landfill leachate.

16.
Heliyon ; 5(8): e02368, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31485542

RESUMO

Understanding the tanker driver hazard awareness on chemical exposure is important to ensure that they are fortified with the appropriate information regarding the risk of their occupation. This present study was conducted to determine the awareness of the petrol tanker driver on the chemical exposure during transportation petroleum product. The assessment on hazardous awareness of the petrol tank driver was conducted through questionnaire survey. Wherein, the questionnaire was designed with considering the variables of age of the driver, working experience, working hours in a day and knowledge on chemical hazard presence in the petroleum oil. A reliability test of Cronbach's Alpha was performed to validate the questionnaire and the Chi-Square test was conducted to determine the correlation among the studied variables. The findings of the present study revealed that the drivers who are frequently come into direct contact with petrol cannot identify the spillage had occurred during working. The study identified that there is an urgency to conduct training on safe handling of petroleum oil in order to eliminate the risk of chemical hazards exposure to the tanker driver.

17.
Data Brief ; 21: 13-17, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30310834

RESUMO

Data on the micrometeorological parameters and Energy Fluxes at an intertidal zone of a Tropical Coastal Ocean was carried out on an installed eddy covariance instruments at a Muka head station in the north-western end of the Pinang Island (5°28'06''N, 100°12'01''E), Peninsula Malaysia. The vast source of the supply of energy and heat to the hydrologic and earth׳s energy cycles principally come from the oceans. The exchange of energies via air-sea interactions is crucial to the understanding of climate variability, energy, and water budget. The turbulent energy fluxes are primary mechanisms through which the ocean releases the heat absorbed from the solar radiations to the environment. The eddy covariance (EC) system is the direct technique of measuring the micrometeorological parameters which allow the measurement of these turbulent fluxes in the time scale of half-hourly basis at 20 Hz over a long period. The data being presented is the comparison of the two-year seasonality patterns of monsoons variability on the measured microclimate variables in the southern South China Sea coastal area.

18.
MethodsX ; 5: 448-453, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30090703

RESUMO

The southern South China coastal oceans within the South East Asian region are much lacking in the perception of the surface energy budget and evaporation over the ocean waters in response to climatic changes. The eddy covariance method was used to measure the energy fluxes, microclimate variables, and surface water temperature from November 2015 to October 2017 at the Straits of Malacca, South China Sea; Pulau Pinang, Malaysia, situated at latitude 5°28'06″N, and longitude 100°12'01″E. This work focused on the methodological approach to the air-sea energy fluxes data collection and analysis. In this regard, the method applied for the direct measurements and analysis of energy fluxes and other meteorological parameters in the site is considered and reported. •The paper summarizes the analysis of energy fluxes, microclimate variables, and surface water temperature data in a tropical coastal ocean station using the eddy covariance method.•The methodological approach illustrates the method of analysis applied in this study which can be compared and used for similar studies in other places.•The reproducible data analysis technique matches similar comparative methods such as Matlab and Python.

19.
Data Brief ; 19: 1477-1481, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30229020

RESUMO

Air-sea flux exchanges influence the climate condition and the global carbon-moisture cycle. It is imperative to understand the fundamentals of the natural systems at the tropical coastal ocean and how the transformation takes place over the time. Hence, latent and sensible heat fluxes, microclimate variables, and surface water temperature data were collected using eddy covariance instruments mounted on a platform at a tropical coastal ocean station from November 2015 to October 2017. The research data is to gain the needful knowledge of the energy exchanges in the tropical climatic environment to further improve predictive algorithms or models. Therefore, it is intended that this data report will offer appropriate information for the Monsoonal, and diurnal patterns of latent (LE) and sensible (H) heats and hence, establish the relationship between microclimate variables on the energy fluxes at the peninsular Malaysian tropical coastal ocean.

20.
Data Brief ; 19: 951-958, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29900392

RESUMO

Although landfilling is still the most suitable method for solid waste disposal, generation of large quantity of leachate is still considered as one of the main environmental problem. Efficient treatment of leachate is required prior to final discharge. Persulfate (S2O82-) recently used for leachate oxidation, the oxidation potential of persulfate can be improved by activate and initiate sulfate radical. The current data aimed to evaluate the performance of utilizing Al2SO4 reagent for activation of persulfate to treat landfill leachate. The data on chemical oxygen demand (COD), color, and NH3-H removals at different setting of the persulfate, Al2SO4 dosages, pH, and reaction time were collected using a central composite design (CCD) were measured to identify the optimum operating conditions. A total of 30 experiments were performed, the optimum conditions for S2O82-/Al2SO4 oxidation process was obtained. Quadratic models for chemical oxygen demand (COD), color, and NH3-H removals were significant with p-value < 0.0001. The experimental results were in agreement with the optimum results for COD and NH3-N removal rates to be 67%, 81%, and 48%, respectively). The results obtained in leachate treatment were compared with those from other treatment processes, such as S2O82- only and Al2SO4 only, to evaluate its effectiveness. The combined method (i.e., /S2O82-/Al2SO4) showed higher removal efficiency for COD, color, and NH3-N compared with other studied applications.

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