Novel Method for Producing Chromic Oxide without Hexavalent Chromium Pollution by Acid Leaching

2021 ◽  
Vol 62 (4) ◽  
pp. 458-465
Author(s):  
Jijun Liu ◽  
Hongmei Lin ◽  
Guorong Hu ◽  
Zhongdong Peng
Keyword(s):  
Hexavalent Chromium ◽  
Acid Leaching ◽  
Chromic Oxide ◽  
Novel Method

A novel method for desulfurization and purification of fluorite concentrate using acid leaching and reverse flotation of sulfide

2019 ◽  
Vol 209 ◽  
pp. 1006-1015 ◽  
Author(s):  
Hang Liu ◽  
Sultan Ahmed Khoso ◽  
Wei Sun ◽  
Yangge Zhu ◽  
Haisheng Han ◽  
...  
Keyword(s):  
Acid Leaching ◽  
Reverse Flotation ◽  
Novel Method

scholarly journals Absorption of inorganic, trivalent and hexavalent chromium following oral and intrajejunal doses in rats

2001 ◽  
Vol 49 (2) ◽  
pp. 203-209 ◽  
Author(s):  
Hedvig Fébel ◽  
B. Szegedi ◽  
Szilvia Huszár
Keyword(s):  
Intestinal Absorption ◽  
Hexavalent Chromium ◽  
Absorption Rate ◽  
Water Soluble ◽  
Chromic Oxide ◽  
Sodium Chromate ◽  
Rat Intestine ◽  
Indicator Method ◽  
Lower Blood ◽  
Chromium Compounds

The intestinal absorption of trivalent and hexavalent chromium (Cr) given orally (experiment I) or infused in the intestine (experiment II) was investigated in rats. The nonabsorbable form of chromium (51Cr2O3) and water-soluble and more absorbable Na251CrO4 (the hexavalent form of Cr) were compared. Total retention of chromium given orally ranged around 15 percent of the dose, regardless of the chromium compounds applied. The absorption rate of chromic oxide, which is considered a nonabsorbable compound, was 14.4 as a percentage of chromium intake. This result indicates that some loss of chromium has to be taken into account in metabolic trials made by the indicator method. In isolated rat intestine, from the injected Cr 2.5% of chromic oxide and 43.2% of sodium chromate were absorbed during an hour (experiment II). The absorbed chromium was transferred to the liver where the liver tissue retained 10.9% of chromic oxide and 51.1% of sodium chromate. Radioactivity of v. cava caudalis following intestinal injection of Na2CrO4 was thirtyfold greater than after Na2CrO4 dosing. This phenomenon can be explained by the lower blood clearance of chromate. Different absorption rate of chromate depending on the route of administration could be due to the fact that the hexavalent form given orally was reduced to Cr3+ in the acidic environment of the stomach. When Na2CrO4 was infused directly in the intestine of rats, such reduction could not occur. This means that the acidic gastric juice might play a role in inhibiting the intestinal absorption of Na2CrO4 when this compound is given orally.

Novel Method for Comprehensive Processing of Low-Grade Copper Concentrate

2018 ◽  
Vol 284 ◽  
pp. 856-862
Author(s):  
Andrey A. Shoppert ◽  
L.M. Karimova ◽  
D.V. Zakharyan
Keyword(s):  
Acid Leaching ◽  
Low Grade ◽  
X Ray Diffraction ◽  
Concentrate Mass ◽  
Copper Concentrate ◽  
Alkali Fusion ◽  
Novel Method ◽  
Copper Aluminum ◽  
Promising Source ◽  
Comprehensive Processing

Low grade copper concentrate, composed mainly of plagioclase, quartz, pyrite, chlorite, chalcopyrite, glauconite, is a promising source for the future recovery of copper and other valuable components which processing by existing methods is not economical. An alkali fusion-leaching method followed by acid leaching for extraction of copper, aluminum, silica, iron and silver from such low-grade copper concentrate was explored in this research. The samples were characterized by using wet chemical analysis and X-ray diffraction. An alkali-fusing-leaching method for processing of low-grade copper concentrate allows to extract in a solution of 62% Si, 70% Fe, 95% Ag, 97% Al and 98% of Cu with the following optimal parameters: NaOH/concentrate mass ratio = 175%, fusion temperature = 375 °C, the fusion time = 90 min. The proposed method is suitable for the comprehensive processing of the low-grade copper concentrate.

scholarly journals A novel method of three-dimensional hetero-spectral correlation analysis for the fingerprint identification of humic acid functional groups for hexavalent chromium retention

RSC Advances ◽  
2018 ◽  
Vol 8 (7) ◽  
pp. 3522-3529 ◽  
Author(s):  
Jia Zhang ◽  
Huilin Yin ◽  
Barnie Samuel ◽  
Fei Liu ◽  
Honghan Chen
Keyword(s):  
Humic Acid ◽  
Correlation Analysis ◽  
Functional Groups ◽  
Hexavalent Chromium ◽  
Three Dimensional ◽  
Fingerprint Identification ◽  
Spectral Correlation ◽  
Novel Method

A method of three-dimensional hetero-spectral correlation analysis was developed for fingerprint identification of humic acid functional groups for Cr(vi) retention.

The removal and morphology of intact biofilms from implanted venous access devices

1995 ◽  
Vol 53 ◽  
pp. 1020-1021
Author(s):  
M.A. Gregory ◽  
G.P. Hadley
Keyword(s):  
Patient Selection ◽  
Surgical Oncology ◽  
Venous Access ◽  
Common Procedure ◽  
Indwelling Catheters ◽  
Careful Patient ◽  
Novel Method ◽  
The Subject ◽  
Vascular Catheters ◽  
Venous Access Devices

The insertion of implanted venous access systems for children undergoing prolonged courses of chemotherapy has become a common procedure in pediatric surgical oncology. While not permanently implanted, the devices are expected to remain functional until cure of the primary disease is assured. Despite careful patient selection and standardised insertion and access techniques, some devices fail. The most commonly encountered problems are colonisation of the device with bacteria and catheter occlusion. Both of these difficulties relate to the development of a biofilm within the port and catheter. The morphology and evolution of biofilms in indwelling vascular catheters is the subject of ongoing investigation. To date, however, such investigations have been confined to the examination of fragments of biofilm scraped or sonicated from sections of catheter. This report describes a novel method for the extraction of intact biofilms from indwelling catheters.15 children with Wilm’s tumour and who had received venous implants were studied. Catheters were removed because of infection (n=6) or electively at the end of chemotherapy.

Longitudinal Changes in Individual BrainAGE in Healthy Aging, Mild Cognitive Impairment, and Alzheimer’s Disease

GeroPsych ◽  
2012 ◽  
Vol 25 (4) ◽  
pp. 235-245 ◽  
Author(s):  
Katja Franke ◽  
Christian Gaser
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Healthy Aging ◽  
Brain Aging ◽  
Elderly Subjects ◽  
Additional Increase ◽  
Longitudinal Changes ◽  
Novel Method ◽  
The Brain

We recently proposed a novel method that aggregates the multidimensional aging pattern across the brain to a single value. This method proved to provide stable and reliable estimates of brain aging – even across different scanners. While investigating longitudinal changes in BrainAGE in about 400 elderly subjects, we discovered that patients with Alzheimer’s disease and subjects who had converted to AD within 3 years showed accelerated brain atrophy by +6 years at baseline. An additional increase in BrainAGE accumulated to a score of about +9 years during follow-up. Accelerated brain aging was related to prospective cognitive decline and disease severity. In conclusion, the BrainAGE framework indicates discrepancies in brain aging and could thus serve as an indicator for cognitive functioning in the future.

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