نتایج جستجو برای: chromium vi extraction

تعداد نتایج: 228606  

2013
Damaris L. Arévalo-Rangel Juan F. Cárdenas-González Víctor M. Martínez-Juárez Ismael Acosta-Rodríguez

A chromium-resistant fungus isolated from contaminated air with industrial vapors can be used for reducing toxic Cr(VI) to Cr(III). This study analyzes in vitro reduction of hexavalent chromium using cell free extract(s) of the fungus that was characterized based on optimal temperature, pH, use of electron donors, metal ions and initial Cr(VI) concentration in the reaction mixture. This showed ...

2013
E. KAPRARA K. SIMEONIDIS A. I. ZOUBOULIS M. MITRAKAS

EXTENDED ABSTRACT Hexavalent chromium [Cr(VI)] has long been recognized as a potential carcinogen, via the inhalation route while nowadays, there is an increasing concern that Cr(VI) is also carcinogenic by the oral route of exposure. According to this, governments apply more stringent regulations for chromium species. There are several discussions and intentions to lower the current maximum pe...

2013
Jigisha Panda Priyabrata Sarkar

Carcinogenic heavy metal chromium, in its hexavalent form (Cr(VI)), is spuriously used in various industrial operations because of its hardness and stability and is found in industrial effluents in concentrations much above WHO’s prescribed limit (50 mg/L). Conventional methods for removing toxic chromium ion (by chemical reduction followed by precipitation, ionexchange and adsorption on activa...

Journal: :Analytical sciences : the international journal of the Japan Society for Analytical Chemistry 2004
Leyu Wang Lun Wang Tingting Xia Ling Dong Guirong Bian Hongqi Chen

Under ultrasonic irradiation, organic fluorescence nanoparticles have been prepared by a reprecipitation method. Compared with single organic fluorophores, these nanoparticles are brighter, more stable against photobleaching and more water-soluble. They also have high room-temperature fluorescence quantum yields (approximately 20%) and a long fluorescence lifetime (approximately 0.2 micros). Ba...

Journal: :Biotechnology and bioengineering 2003
Sarah S Middleton Rizlan Bencheikh Latmani Mason R Mackey Mark H Ellisman Bradley M Tebo Craig S Criddle

Microbial reduction is a promising strategy for chromium remediation, but the effects of competing electron acceptors are still poorly understood. We investigated chromate (Cr(VI)) reduction in batch cultures of Shewanella oneidensis MR-1 under aerobic and denitrifying conditions and in the absence of an additional electron acceptor. Growth and Cr(VI) removal patterns suggested a cometabolic re...

2013
J. A. S. Ting L. M. D. Rosario A. M. Ulano H. V. Lee H. J. Ramos R. B. Tumlos

This study deals with the enhancement of chromium (VI) removal by vacuum drying and plasma pre-treatments of cocolumber (Cocos nucifera) sawdust. For fixed adsorbent dose and pH, the effects of important parameters such as initial adsorbate concentration and contact time are determined. Results show that both pre-treatments increased the adsorption efficiency of the sawdust. The adsorption data...

2017
Priyanka Saha Omkar Shinde Supriya Sarkar

The wastewater at Sukinda chromite mines (SCM) area of Orissa (India) showed high levels of toxic hexavalent chromium (Cr VI). Wastewater from chromium-contaminated mines exhibit potential threats for biotic community in the vicinity. The aim of the present investigation is to develop a suitable phytoremediation technology for the effective removal of toxic hexavalent chromium from mines wastew...

2012
Anna Długosz Krzysztof P. Rembacz Anna Pruss Marta Durlak Jadwiga Lembas-Bogaczyk

Hexavalent chromium (VI) compounds are widely used in industry, while trivalent chromium (III) is used as a nutritional supplement. CrVI is generally considered more toxic and carcinogenic than its trivalent form and the toxicity of this metal is associated with free radical processes generating reactive oxygen species (ROS). The detailed mechanism of ROS formation by chromium and its compounds...

Journal: :مجله علمی دانشگاه علوم پزشکی رفسنجان 0
اطهر انتظاری a. entezari south khorasan- birhand إهدانشجوی کارشناسی مهندسی بهداشت محیط، عضو کمیته تحقیقات دانشجویی، دانشکده بهداشت، دانشگاه علوم پزشکی بیرجند، بیرجند، ایراسازمان اصلی تایید شده: دانشگاه علوم پزشکی بیرجند (birjand university of medical sciences) رسول خسروی r. khosravi south khorasan- birhand إه(نویسنده مسئول) مربی، عضو مرکز تحقیقات عوامل اجتماعی مؤثر بر سلامت، گروه مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوسازمان اصلی تایید شده: دانشگاه علوم پزشکی بیرجند (birjand university of medical sciences) فاطمه السادات ارغوان f.s. arghavan south khorasan- birhand إهدانشجوی کارشناسی مهندسی بهداشت محیط، عضو کمیته تحقیقات دانشجویی، دانشکده بهداشت، دانشگاه علوم پزشکی بیرجند، بیرجند، ایراسازمان اصلی تایید شده: دانشگاه علوم پزشکی بیرجند (birjand university of medical sciences) علی اکبر تقی زاده a. a. taghizadeh south khorasan- birhand إهکارشناس مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی بیرجند، بیرجند، ایرانسازمان اصلی تایید شده: دانشگاه علوم پزشکی بیرجند (birjand university of medical sciences) مریم خدادادی m. khodadadi south khorasan- birhand إهمربی، گروه مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی بیرجند، بیرجند، ایرانسازمان اصلی تایید شده: دانشگاه علوم پزشکی بیرجند (birjand university of medical sciences) هادی اسلامی h. eslami yazd, shahid sadoughi university of medical sciencesدانشجوی دکتری مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی و خدمات بهداشتی درمانی یزد، یزد، ایرانسازمان اصلی تایید شده: دانشگاه علوم پزشکی شهید صدوقی یزد (shahid sadooghi university of medical sciences)

background and objectives: because of toxical and hazardous properties of hexavalent chromium (cr(vi)), its removal by an economical and efficient method is necessary. the use of activated carbon, as an adsorbent, is a common and effective method for hexavalent chromium removal. thus the aim of this study was to produce granular and powdered activated carbon form peganum harmala and compare the...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید