نتایج جستجو برای: شاخص cr
تعداد نتایج: 119928 فیلتر نتایج به سال:
An ETAAS method was validated to quantify total Cr and Cr(VI) in mushrooms and the underlying soils. The method includes a sample pretreatment for total Cr dissolution using a wet acid digestion procedure and a selective alkaline extraction for Cr(VI). The limits of detection were, expressed in microg/L, 0.15 and 0.17 for total Cr and Cr(VI), respectively. The linearity ranges under the optimiz...
سد باطله معدن مس سرچشمه حاوی فلزات سنگین زیادی است. به این منظور، رسوبات مجتمع مس سرچشمه، برای تعیین غلظت فلزات سنگین و شدت آلودگی، آنالیز شیمیایی شدند. در واقع، هدف این پژوهش، ارزیابی میزان آلودگی فلزات سنگین (Co، Cu، Mo، Zn، Cr، Mn، Ni، Pb، Ti و Fe) در رسوبات معدن مس سرچشمه منتهی به سد باطله است. در این پژوهش، شاخصهای آلودگی نظیر ضریب آلودگی، شاخص بار آلودگی، فاکتور غنیشدگی و شاخص زمینانب...
سازندهای رازک و میشان (میوسن پیشین تا میوسن میانی) در مناطق پل کوار و زنجیران در جنوب و جنوب غرب فارس و در کمربند چین خورده ی زاگرس بررسی شدند. کانیهای اصلی عبارتند از ایلیت- موسکویت، کلریت، کلسیت، کوارتز و کانیهای فرعی آلبیت و پالی گورسکیت. از نظر ژئوشیمی مقادیر mgo و cao بالاتر و مقادیر sio2، al2o3، fe2o3، na2o وk2o کمتر از نمونههای استاندارد nasc، paas وuc را نشان میدهد. الگوی ree بهنجا...
Over the past 60 years, dose-response patch test studies by various methods have been conducted in an attempt to identify the minimum elicitation threshold (MET) concentration of hexavalent chromium (Cr(VI)) that produces an allergic response in Cr(VI) sensitive subjects. These data are not adequate, however, to provide an accurate estimate of the MET because of the variability in the patch tes...
to evaluatethe effects of supplementing diets of growing japanese quails (n=450; 7 days old) with chromium (cr) yeast and / or mannan oligosaccharides (mos) on productive performance, carcass traits and the immune system are reported. diets were a basal diet (control) or the basal diet supplemented with 600 mg cr-yeast/kg (cr 1), 1200 mg cr-yeast/kg (cr 2), 1.0 g mos/kg, cr 1 + mos or cr 2 + mo...
Reduction of chromium toxicity by applying various soil amendments in artificially contaminated soil
Six soil amendments including municipal solid waste compost (MSWC), coal fly ash (CFA), rice husk biochar prepared at 300°C (B300) and 600°C (B600), zerovalent iron (Fe0), and zerovalent manganese (Mn0) were evaluated to determine their ability to reduce mobility of chromium (Cr) in a Cr-spiked soil. The Cr-spiked soil samples were separately incubated with selected amendments at 2 and 5% [weig...
In this study, the concentrations of Zn and Cr in downstream waters from Uzunçayır Dam (Tunceli, Turkey) were monitored during spring (March, April, May) and summer (June, July, August) season. Zinc and Cr concentrations in surface water samples were detected using the ICP-MS device. According to the data obtained the lowest Zn and Cr concentrations in the spring season were 65.43±3.2 μg/L in M...
In this study, the concentrations of Zn and Cr in downstream waters from Uzunçayır Dam (Tunceli, Turkey) were monitored during spring (March, April, May) and summer (June, July, August) season. Zinc and Cr concentrations in surface water samples were detected using the ICP-MS device. According to the data obtained the lowest Zn and Cr concentrations in the spring season were 65.43±3.2 μg/L in M...
Naturally occurring Cr(VI) has recently been reported in ground and surface waters. Rock strata rich in Cr(III)-bearing minerals, in particular chromite, are universally found in these areas that occur near convergent plate margins. Here we report experiments demonstrating accelerated dissolution of chromite and subsequent oxidation of Cr(III) to aqueous Cr(VI) in the presence of birnessite, a ...
This article first briefly reviews the basic concepts about cognitive radio (CR) technology and CRenabled cognitive wireless communications, and then discusses the differentiating features of CR and the fundamental theories or principles behind CR, especially from the artificial intelligence and machine learning perspective. As a CR testbed plays an important role in the transition of CR techno...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید