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71.
Wan Saime Wan Ngah Noorul Farhana Md Ariff Megat Ahmad Kamal Megat Hanafiah 《Water, air, and soil pollution》2010,206(1-4):225-236
The preparation, characterization, and environmental application of crosslinked chitosan-coated bentonite (CCB) beads for tartrazine adsorption have been investigated. CCB beads were characterized by using Fourier transform infrared spectrophotometer (FTIR), scanning electron microscope (SEM), and Brunauer–Emmett–Teller (BET) surface area and Barrett–Joyner–Halenda (BJH) pore size distribution analyses were also determined. The values of pH of the aqueous slurry and pH of zero point charge (pHZPC) were almost equal. The adsorption at equilibrium of tartrazine was found to be a function of pH of the solution, stirring rate, contact time, and tartrazine concentration. The optimum conditions for tartrazine adsorption were pH 2.5, stirring rate of 400 rpm and contact time of 80 min. Pseudo-first-order and pseudo-second-order models were used to analyze the kinetics of adsorption with the latter found to agree well with the kinetics data, suggesting that the rate determining step may be chemisorption. The two most common isotherm models, Langmuir and Freundlich, were used to describe the adsorption equilibrium data. On the basis of Langmuir isotherm model, the maximum adsorption capacities were determined to be 250.0, 277.8, and 294.1 mg g?1 at 300, 310, and 320 K, respectively. Desorption studies were carried out at different concentrations of EDTA, H2SO4, and NaOH. All desorbing solutions showed poor recovery of tartrazine. 相似文献
72.
Aneela Zameer Durrani Sagar M. Goyal Nadeem Kamal 《Journal of Equine Veterinary Science》2011,31(8):427-429
To determine the seroprevalence of Borrelia burgdorferi antibodies in horses in Minnesota, the database of the Veterinary Diagnostic Laboratory, University of Minnesota, was searched over a 10-year period (May 2001 to May 2010). A total of 1,260 equine serum samples submitted by 112 veterinary clinics were tested using an indirect fluorescent antibody test. Samples with titers of ≥1:320 were considered positive. The average rate of seroprevalence was 58.7%, indicating high exposure of horses to B burgdorferi in Minnesota. Our results indicate that borreliosis should be considered as a differential in cases of horses with undiagnosed musculoskeletal or neurologic disease. 相似文献
73.
Acacia senegal, the gum arabic producing tree, is the most important tree species for the livelihood of the people in South Kordofan State, Sudan. The objective of this study was to determine the optimum tapping date for gum arabic production in the study area. A randomized complete block design experiment with three replications was conducted at (Meari) area for two continuous growing seasons 2008/2009 - 2009/2010. The treatments comprised six tapping dates (1 Oct, 15 Oct, 1 Nov, 15 Nov, 1 Dec, and 15 Dec). Results showed highly significant differences (p < 0.001) in gum arabic yield (g\tree) in all pickings and in the total gum yield between the tapping dates. The results also showed that tapping of trees on 15 October and 1 November gave a higher yield compared to the other dates. The highest gum yield of 1086.6 and 661.2 g/tree was recorded on 15 October and 15 November, while the lowest gum yield of 297.9 g/tree was recorded when the trees were tapped on 1 October. The two highest-yield dates of tapping (15 Oct and 1 Nov) are recommended as the best time for tapping for gum arabic production in South Kordofan State. These results can be used to increase gum arabic production and farmer income in South Kordofan State. 相似文献
74.
Frederick T. Short Beth Polidoro Suzanne R. Livingstone Kent E. Carpenter Salomão Bandeira Japar Sidik Bujang Hilconida P. Calumpong Tim J.B. Carruthers Robert G. Coles William C. Dennison Paul L.A. Erftemeijer Miguel D. Fortes Aaren S. Freeman T.G. Jagtap Abu Hena M. Kamal Gary A. Kendrick W. Judson Kenworthy Yayu A. La Nafie Ichwan M. Nasution Robert J. Orth Anchana Prathep Jonnell C. Sanciangco Brigitta van Tussenbroek Sheila G. Vergara Michelle Waycott Joseph C. Zieman 《Biological conservation》2011,(7):1961-1971
Seagrasses, a functional group of marine flowering plants rooted in the world’s coastal oceans, support marine food webs and provide essential habitat for many coastal species, playing a critical role in the equilibrium of coastal ecosystems and human livelihoods. For the first time, the probability of extinction is determined for the world’s seagrass species under the Categories and Criteria of the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. Several studies have indicated that seagrass habitat is declining worldwide. Our focus is to determine the risk of extinction for individual seagrass species, a 4-year process involving seagrass experts internationally, compilation of data on species’ status, populations, and distribution, and review of the biology and ecology of each of the world’s seagrass species. Ten seagrass species are at elevated risk of extinction (14% of all seagrass species), with three species qualifying as Endangered. Seagrass species loss and degradation of seagrass biodiversity will have serious repercussions for marine biodiversity and the human populations that depend upon the resources and ecosystem services that seagrasses provide. 相似文献
75.
Jain N Dhawan K Malhotra S Singh R 《Plant foods for human nutrition (Dordrecht, Netherlands)》2003,58(4):309-315
Changes in chemical composition and the activities of hydrolytic enzymes during four different stages of maturity, viz. mature green (MG), color turning (CT), ripe (R), and overripe (OR), have been studied in guava fruits cv. Banarsi Surkha. Chlorophyll content decreased while carotenoid content increased during ripening. Starch content decreased with concomitant increase in alcohol-soluble sugars. Cellulose, hemicellulose, and lignin also decreased up to ripe stage, while pectin continued to decrease up to OR stage. PG (polygalacturonase) and cellulase exhibited progressive increase in activity throughout ripening, whereas pectin methyl esterase (PME) activity increased up to CT stage and decreased at R stage. The activities of alpha-amylase and beta-amylase decreased significantly with ripening. The most notable metabolic changes occurred between MG and CT stage, implying that for improved postharvest handling, guava fruits may be harvested at CT stage. 相似文献
76.
Preeti Rawat Mohammad F. Khan Manmeet Kumar Akhilesh K. Tamarkar Arvind K. Srivastava Kamal R. Arya Rakesh Maurya 《Fitoterapia》2010
Two new phenolic glycosides (1, 2), along with fourteen known compounds (3–16) have been isolated from the fruit of Cupressus sempervirens. The structures of these compounds were determined by spectroscopic analysis and were evaluated for their inhibitory activity against glycogen phosphorylase and glucose-6-phosphatase enzymes. Compounds 14 showed a moderate inhibition against glucose-6-phosphatase and 15 against glycogen phosphorylase enzymes. 相似文献
77.
Kamal Sarma K. Prabakaran P. Krishnan G. Grinson A. Anand Kumar 《Aquaculture International》2013,21(1):183-196
The study was conducted to assess the effects of salinity on growth and biochemical composition of freshwater catfish, Clarias batrachus. A static nonrenewable acute toxicity bioassay test was conducted and LC50 of salinity for 96-h exposure to the fingerling (14.5 cm) was 12.52 ‰. Based on these results, two sublethal salinity levels, viz. 4 and 8 ‰ were selected to study the long-term effects of salinity on C. batrachus for a period of 90 days. From the study, it was found that growth and survival rate were less in saline water (4 and 8 ‰). Maximum growth and survival were recorded in freshwater (0 ‰ salinity) and subsequently at 4 and 8 ‰. To assess the biochemical alteration, few important biomarkers were estimated. At the end of 90 days rearing period, glucose level in the brain and blood of C. batrachus was found to decrease with salinity. The level of liver and muscle glycogen in the fish reared at 4 ‰ was lower than that of control. Ascorbic acid in all organs under study was found to decrease with increasing salinity, which was attributed to stress mitigation effect of vitamin C. Acetylcholine esterase (AchE) activity recorded a gradual decrease with increasing salinity. Metabolic enzymes, alkaline phosphatase (ALP) activity and adenosine triphosphosphtase (ATPase) activity also reduced both in liver and muscle tissues with increasing salinity. From the present investigation, it can be concluded that exposure to higher salinity significantly (P < 0.01) affects the growth and physiological response of Clarias batrachus. 相似文献
78.
The effect of knot density, pile height, number of ply in pile yarn and pile yarn twist on abrasion resistance of Persian handmade wool carpets has been studied. The interaction between the process variables has been analyzed by using response surface methodology based on the Box-Behnken design of experiment. Knot density, pile height, interactions between knot density and pile height; pile height and pile yarn twist; as well as squares of the knot density, pile height and number of ply in pile yarn are significant process variables. The minimum abrasion loss occurs at the combination(s) of medium values of knot density (six knots per inch) and number of ply in pile yarn (three ply) as well as lower values of pile height (ten mm) and pile yarn twist (three and a half twists per inch). 相似文献
79.
A correlation between heterozygosity of genotypes and survival (fitness) was studied in eight natural populations of Pinus roxburghii through isozyme analysis using horizontal starch gel electrophoresis. Under each population, 20 mother trees of different
ages (30 to more than 100 years) were selected which were at least 50 m apart. From each tree, eight seeds were assayed for
eleven enzyme systems viz., Aconitase, Aspertate aminotransferase, Glutamate dehydrogenase, Isocitrate dehydrogenase, Leucine-amino
peptidase, Malate dehydrogenase, Menadione reductase, Phosphoglucose isomerase, Phosphoglucomutase, 6-Phosphogluconate dehydrogenase
and Shikimic acid dehdrogenase which were found to be encoded by 18 polymorphic loci. Genetic constitution of the mother trees
was determined by analysing endosperms and embryos separately. The number of alleles in the progeny (embryos) and the mother
trees varied from 38 to 42 and 34 to 37, respectively, in all the populations. Distribution of degree of heterozygosity and
fixation index for the progeny and the mother trees were calculated. The mother trees showed a substantial shift towards higher
degree of heterozygosity as compared to the progeny. Fixation index values were significantly higher and negative for the
mother trees as compared to the progeny, which revealed that heterozygosity was positively correlated with survival in P. roxburghii.
Application: Heterozygous geneotypes in tree species are shown to have better survival over homozygotes under diverse environmental
conditions. Every year, millions of Pinus roxburghii saplings are planted in India. However, the fact that survival is very low might possibly be due to inbred/homozygous plants
that suffer from fitness disadvantage. Our study indicates that heterozygotes have a better chance of survival under environmental
conditions. The use of heterozygotes should lead to effective establishments of Pinus roxburghii plantations. 相似文献
80.
Do socio-psychological factors matter in agroforestry planning? Lessons from smallholder traditional agroforestry systems 总被引:1,自引:0,他引:1
Most of the well planned rural development forestry programs of the 1970s, and agroforestry in particular, were either not
adopted by the intended beneficiaries or failed to meet the needs and aspirations of the rural people, particularly in the
developing countries. The reasons for non-adoption in some cases appear to be technical, bio-physical, social and economic
(termed as rational reasons by the planners), but in other situations the reasons are not so easily recognisable and comprehended
(termed irrational reasons). These irrational reasons are the perceptions and attitude of the farmer towards farm practices,
and their role in agroforestry planning has remained almost completely neglected. The present study is based on a household
survey of the farmers in traditional agroforestry systems of Western Himalaya and investigates the importance of perceptional
and attitudinal aspects of the farmers with regard to agroforestry adoption and extension. In the present study, farmers’
perceptions of restrictions on felling of trees from their own land and attitudes towards agroforestry were the most important
sociopsychological factors which influenced tree growing. This study implies a need to take into account the socio-psychological
factors of the farmers for planning socially acceptable agroforestry programs. The importance of study of various de jure rules and regulations controlling the use of on-farm tree resources and related exemptions and their association with farmers’
perceptions and tree growing is highlighted to develop policies to encourage tree growing in agroforestry. 相似文献