This research was conducted in the Qassim region, Kingdom of Saudi Arabia. The goal of this research is to determine the percentage of silicon in the Rub al-Khali desert. Samples were collected from four cities locate...This research was conducted in the Qassim region, Kingdom of Saudi Arabia. The goal of this research is to determine the percentage of silicon in the Rub al-Khali desert. Samples were collected from four cities located in the Al-Qassim Region of Saudi Arabia (Uyun Al-Jawa, Al-Fuwailiq, Al-Sulaibiya, and Al-Qawara), from three distinct depths (the earth’s surface, 50 cm, and 100 cm). The percentages of silicon in these places vary between the highest value for silicon dioxide, which is 74.47 m/m%, and 34.8 m/m% for silicon in Al-Qawara city at a depth of 100 cm. We used an x-ray fluorescence (XRF) instrument to evaluate the samples. There are high percentage of both silica and silicon in the Nafud desert. Studies have shown that these ratios can help investors benefit from an element of Silicon and silicon dioxide, so the sands of the Nafud desert is sufficient for extracting Silicon and silica in huge quantities. This may transform the Kingdom into a leading country in the global computer technology industry that depends on silicon extracted from the desert sands, the most important of which are microcomputer data processing devices.展开更多
Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, ...Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, concentrations average in mg/L of metals such Fe (0.731), Mn (0.345), Cr (0.070), Cu (0.014) and concentrations of nutrients known to be pollutants and toxic for living or-ganisms. These heavy metals are dangerous to the lives, the local inhabitants and also a threat to aquatic life since this water is essential for the economical town, Abidjan. According to the Manganese concentration average (0.345 mg) values that higher than WHO (0.05 mg) value, the main likely source of pollu-tants is anthropogenic, industrial and agricultural. This study also shows the use of materials and lubricants near the lagoon that pollute this water.展开更多
Double-layer organic electroluminescent devices have been constructed. A new fluorescent dye, 9,10-bis(phenylethynyl)anthracence, was chosen as the dopant which was molecularly dispersed in the polymer film, and green...Double-layer organic electroluminescent devices have been constructed. A new fluorescent dye, 9,10-bis(phenylethynyl)anthracence, was chosen as the dopant which was molecularly dispersed in the polymer film, and green light was observed from the device with luminance of 130cd/m(2) at 17V.展开更多
Objective:The aim of this study was to clarify the differences between the prostatic levels of chemical elements in patients with benign prostatic hyperplasia(BPH)and healthy male.Methods:We evaluated the prostatic le...Objective:The aim of this study was to clarify the differences between the prostatic levels of chemical elements in patients with benign prostatic hyperplasia(BPH)and healthy male.Methods:We evaluated the prostatic level of 66 chemical elements in 43 patients with BPH and 37 healthy males.Measurements were performed using five instrumental analytical methods.Results:In the hyperplastic prostates,we have observed a significant increase in the mean level of Bi,Cr,Hg,K,Sb,and Se accompanied a significant decrease in the mean level of Al,Ce,Cs,Dy,Er,Gd,Ho,La,Mo,Nd,Pb,Pr,Sm,Sn,Tb,Tm,U,and Y.No differences were found in the mean prostatic level of other chemical elements including Ag,Al,Au,B,Ba,Be,Br,Ca,Cd,Co,Cu,Fe,Li,Mg,Mn,Na,Nb,Ni,P,Rb,S,Sc,Si,Th,Ti,Tl,Yb,Zn,and Zr between BPH patients and healthy males.Conclusions:The finding of chemical element contents and correlation between pairs of chemical element mass fractions indicates that there is a great disturbance of prostatic chemical element metabolism in BPH gland.Trace elements Bi,Cr,Hg,K,Sb,and Se may be regarded as the possible tissue biomarkers of hyperplastic transformation of prostate gland.Obtained data did not confirm a critical role of Cd and Pb accumulation in the pathogenesis of BPH.A potential age-related Zn,Fe,and Se deficiency in the prostate tissue has not been found as being involved in the etiology of BPH.展开更多
Soil erosion and associated sediment redistribution are key environmental problems in Central Argentina.Specific land uses and management practices,such as intensive grazing and crop cultivation,are considered to be s...Soil erosion and associated sediment redistribution are key environmental problems in Central Argentina.Specific land uses and management practices,such as intensive grazing and crop cultivation,are considered to be significantly driving and accelerating these processes.This research focuses on the identification of suitable soil tracers from hot spots of land degradation and sediment fate in an agricultural catchment of central Argentina with erodible loess soils.Using Energy Dispersive X-Ray Fluorescence(EDXRF),elemental concentrations were determined and later used as soil tracers for geochemical characterization.The best set of tracers were identified using two artificial mixtures composed of known proportions of soil sources collected from different lands having contrasting soil uses.Barium,calcium,iron,phosphorus,and titanium were identified for obtaining the best suitable reconstruction of source proportions in the laboratory-prepared artificial mixtures.Then,these elements,as well as the total organic carbon,were applied for pinpointing critical hot spots of erosion within the studied catchment.Feedlots were identified to be the main source of sediments,river banks and dirt roads together are the second most important source.This investigation provides key information for optimizing soil conservation strategies and selecting land management practices and land uses which do not generate great contribution of sediment,preventing pollution of the waterways of the region.展开更多
文摘This research was conducted in the Qassim region, Kingdom of Saudi Arabia. The goal of this research is to determine the percentage of silicon in the Rub al-Khali desert. Samples were collected from four cities located in the Al-Qassim Region of Saudi Arabia (Uyun Al-Jawa, Al-Fuwailiq, Al-Sulaibiya, and Al-Qawara), from three distinct depths (the earth’s surface, 50 cm, and 100 cm). The percentages of silicon in these places vary between the highest value for silicon dioxide, which is 74.47 m/m%, and 34.8 m/m% for silicon in Al-Qawara city at a depth of 100 cm. We used an x-ray fluorescence (XRF) instrument to evaluate the samples. There are high percentage of both silica and silicon in the Nafud desert. Studies have shown that these ratios can help investors benefit from an element of Silicon and silicon dioxide, so the sands of the Nafud desert is sufficient for extracting Silicon and silica in huge quantities. This may transform the Kingdom into a leading country in the global computer technology industry that depends on silicon extracted from the desert sands, the most important of which are microcomputer data processing devices.
文摘Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, concentrations average in mg/L of metals such Fe (0.731), Mn (0.345), Cr (0.070), Cu (0.014) and concentrations of nutrients known to be pollutants and toxic for living or-ganisms. These heavy metals are dangerous to the lives, the local inhabitants and also a threat to aquatic life since this water is essential for the economical town, Abidjan. According to the Manganese concentration average (0.345 mg) values that higher than WHO (0.05 mg) value, the main likely source of pollu-tants is anthropogenic, industrial and agricultural. This study also shows the use of materials and lubricants near the lagoon that pollute this water.
文摘Double-layer organic electroluminescent devices have been constructed. A new fluorescent dye, 9,10-bis(phenylethynyl)anthracence, was chosen as the dopant which was molecularly dispersed in the polymer film, and green light was observed from the device with luminance of 130cd/m(2) at 17V.
文摘Objective:The aim of this study was to clarify the differences between the prostatic levels of chemical elements in patients with benign prostatic hyperplasia(BPH)and healthy male.Methods:We evaluated the prostatic level of 66 chemical elements in 43 patients with BPH and 37 healthy males.Measurements were performed using five instrumental analytical methods.Results:In the hyperplastic prostates,we have observed a significant increase in the mean level of Bi,Cr,Hg,K,Sb,and Se accompanied a significant decrease in the mean level of Al,Ce,Cs,Dy,Er,Gd,Ho,La,Mo,Nd,Pb,Pr,Sm,Sn,Tb,Tm,U,and Y.No differences were found in the mean prostatic level of other chemical elements including Ag,Al,Au,B,Ba,Be,Br,Ca,Cd,Co,Cu,Fe,Li,Mg,Mn,Na,Nb,Ni,P,Rb,S,Sc,Si,Th,Ti,Tl,Yb,Zn,and Zr between BPH patients and healthy males.Conclusions:The finding of chemical element contents and correlation between pairs of chemical element mass fractions indicates that there is a great disturbance of prostatic chemical element metabolism in BPH gland.Trace elements Bi,Cr,Hg,K,Sb,and Se may be regarded as the possible tissue biomarkers of hyperplastic transformation of prostate gland.Obtained data did not confirm a critical role of Cd and Pb accumulation in the pathogenesis of BPH.A potential age-related Zn,Fe,and Se deficiency in the prostate tissue has not been found as being involved in the etiology of BPH.
基金CONICET,Argentina PROICO 22/F41 PIP 11220150100334Universidad Nacional de San Luis,Argentina RLA 5076 ARCAL RLA 5064 and ARCAI
文摘Soil erosion and associated sediment redistribution are key environmental problems in Central Argentina.Specific land uses and management practices,such as intensive grazing and crop cultivation,are considered to be significantly driving and accelerating these processes.This research focuses on the identification of suitable soil tracers from hot spots of land degradation and sediment fate in an agricultural catchment of central Argentina with erodible loess soils.Using Energy Dispersive X-Ray Fluorescence(EDXRF),elemental concentrations were determined and later used as soil tracers for geochemical characterization.The best set of tracers were identified using two artificial mixtures composed of known proportions of soil sources collected from different lands having contrasting soil uses.Barium,calcium,iron,phosphorus,and titanium were identified for obtaining the best suitable reconstruction of source proportions in the laboratory-prepared artificial mixtures.Then,these elements,as well as the total organic carbon,were applied for pinpointing critical hot spots of erosion within the studied catchment.Feedlots were identified to be the main source of sediments,river banks and dirt roads together are the second most important source.This investigation provides key information for optimizing soil conservation strategies and selecting land management practices and land uses which do not generate great contribution of sediment,preventing pollution of the waterways of the region.