The volcano-sedimentary succession around Wadi Zaghra in Sinai, at the northernmost segment of the Arabian Nubian Shield, comprises volcanic rocks interbedded with rather immature sediments. The succession is dominate...The volcano-sedimentary succession around Wadi Zaghra in Sinai, at the northernmost segment of the Arabian Nubian Shield, comprises volcanic rocks interbedded with rather immature sediments. The succession is dominated by intermediate to silicic volcanics of medium-to high-K calc-alkaline affinity. It is divided into two units, the lower unit includes intermediate rocks and dacites interbedded with graywackes, semi-pelites and pelites and topped by polymict conglomerates. This unit is subjected to folding and regional metamorphism(up to garnet zone) and is intruded by quartz diorite-granodiorite inducing, locally, low-pressure contact thermal metamorphism. The unmetamorphosed upper unit encompasses acid volcanics intercalated with litharenite, sublitharenite and minor arenite. The rhyolites of this unit pertain to the highly fractionated granites and are characterized by an agpaitic index(NK/A) ranging from 0.87 to 0.96. They may reflect either extensive interaction of subduction-related magmas with the continental crust or a change in the tectonic regime. The present lithological and geochemical characteristics of the studied sediments together with available zircon ages indicate rather distal provenance of their detritus. This detritus comprises fluvial-alluvial sediments accumulated in the intermontane basins, which are half-grabens or tilted fault blocks. The tectonic setting of the depositional basins is active continental margin and continental island arcs. Geochemical patterns of the Zaghra volcano-sedimentary succession indicate their correlation with the Dokhan Volcanics-Hammamat Clastics sequence of the Eastern Desert of Egypt. Also, the Zaghra volcanics display geochemical similarities with those exposed in Sinai, at the Rutig, Ferani and Iqna Shar'a areas. The Zaghra succession is dated as Ediacaran but is not related either to the ensimatic island arc assemblage or to the rift-related assemblage formed during the early stages of the break-up of Rodinia as previously thought.展开更多
Objective: To investigate the possible protective and/or therapeutic potentials of Dunaliella salina(D. salina) biomass, its carotenoid and polar fractions on cardiac dysfunction associated with D-galactose(D-GAL) ind...Objective: To investigate the possible protective and/or therapeutic potentials of Dunaliella salina(D. salina) biomass, its carotenoid and polar fractions on cardiac dysfunction associated with D-galactose(D-GAL) induced aging in rats. Methods: Aging associated cardiac dysfunction was induced in rats by injection of D-GAL(200 mg/kg; i.p) for 8 weeks. D-GAL injected rats were treated with two regimens; protective regimen where D. salina biomass(250 mg/kg), its carotenoid(250 μg/kg) and polar(250 μg/kg) fractions were given orally for two weeks concurrently with D-GAL injection as well as treatment regimen where the three treatments were given orally for 28 consecutive days after D-GAL injection. Results: D-GAL injection for 8 weeks was accompanied with dramatic electrocardiographic changes as well as profound elevation in serum levels of homocysteine, creatinine kinase isoenzyme and lactate dehydrogenase in addition to the reduction of the cardiac content of glucose trasporter 4. D-GAL also induced reduction in cardiac superoxide dismutase activity and elevation of inducible nitric oxide synthetase and interleukin-6. On the other hand, oral administration of D. salina carotenoid fraction as well as the total biomass significantly attenuated the D-GAL-induced disturbances in the above mentioned parameters where the protective regimen appeared more successful in controlling the manifestations of cardiac dysfunction. The histopathological examination further emphasized the promising results. Besides, the HPLC analysis of the carotenoid fraction of D. salina revealed the presence of 2.31%. salina carotenoid fraction as well as the total biomass amelior β-carotene. Conclusions: Date D-GAL-induced aging associated cardiac dysfunction which is attributed to the potent antioxidant activity of β-carotene.展开更多
The Sa'al Metamorphic Complex(SMC;southern Sinai)encompasses the oldest arc rocks in the Arabian–Nubian Shield,comprising two non-consanguineous metavolcanic successions(the Agramiya Group and the Post-Ra'aya...The Sa'al Metamorphic Complex(SMC;southern Sinai)encompasses the oldest arc rocks in the Arabian–Nubian Shield,comprising two non-consanguineous metavolcanic successions(the Agramiya Group and the Post-Ra'ayan Formation)separated by the metasediments of the Ra'ayan Formation.It experienced three distinct deformational events(D_(1)–D_(3))and two low-medium grade regional metamorphic events(M_1–M_(2)).The Agramiya Group and the Ra'ayan Formation experienced all tectonometamorphic events(D_1–D_(3)and M_(1)–M_(2)),whereas the Post-Ra'ayan volcanic rocks were only affected by the D_(3)and M_(2)events.D_(1)is an extensional event and is connected to the late Rodinia break-up(~Tonian;900–870 Ma).The M_(1)metamorphism variably affected the older Agramiya Group,the rhyolitic tuffs experiencing lower to upper greenschist facies conditions and the basic and intermediate volcanic rocks undergoing amphibolite facies metamorphism.The Ra'ayan Formation metasediments experienced upper greenschist to amphibolite facies metamorphism.The upper greenschist facies M_(2)affected the youngest Post-Ra'ayan volcanic rocks and other stratigraphic successions.The compressive D_(2)and D_(3)events were coeval with the accretion of dismembered terranes in the assembly of Gondwana.D_(2)can be linked to the Tonian–Cryogenian arc-arc assembly(~880–760 Ma;in Elat and Sinai),whereas D_(3)and the accompanying M_(2)is constrained to 622–600 Ma(Ediacaran).展开更多
Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)method.The temperature was increased to avoid the bubbles and cracks ...Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)method.The temperature was increased to avoid the bubbles and cracks which may be formed during the preparation of the ingot material.We have started with the flux higher than the normal to avoid the bubbles and make good treatment for the solid-liquid interface.The structures of both Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)were studied by using x-ray diffraction(XRD).Optical properties for C12A7 and Y-C12A7 single crystals have been studied in order to determine the optical parameters such as optical energy gap(Eg),refractive index n,oscillating energy(Eo),dispersion energy(Ed),volume energy loss function(VELF),and surface energy loss function(SELF).Finally,a new result for these samples is that the third-order nonlinear optical susceptibility(χ(3))was determined.The results have been discussed with effect of Y-doping on the C12A7 single crystals for optical and industrial applications.展开更多
Zinc (Zn (II) HEDTA) was used to determine their effect on salt-induced damages in maize plants. The aim of this study was to investigate the antioxidant capacity and the levels of enhanced total phenolic (TPC), total...Zinc (Zn (II) HEDTA) was used to determine their effect on salt-induced damages in maize plants. The aim of this study was to investigate the antioxidant capacity and the levels of enhanced total phenolic (TPC), total flavonoid (TFC) contents and their antioxidant activity in leaves of two maize cultivars Single cross 10 (SC10) and Single cross 162 (SC162) grown in two levels of salinity 0.00 and 100 mmol in response to 20 μmol Zn (II) HEDTA foliar spray treatments. Significant differences (P ≤ 0.05) in amounts of TPC ranged from (2.55 to 4.62 mg/gdw as Gallic) in Single cross 10 (SC10) and from (2.53 to 4.38 mg/gdw as Gallic) in Single cross 162 (SC162), TFC (ranged 1.53 to 2.41 mg/gdw as qurestien) in Single cross 10 (SC10) and from (1.28 to 2.41 mg/gdw as qurestien) in Single cross 162 (SC162) among all treated plants were observed. The levels of their compounds increase related to foliar spraying of Zn (II) HEDTA. A significant positive correlation between TPC, TFC and DPPH scavenging activity and iron chelating activity was observed which shows that phenolic compounds were involved in the mechanism of salt tolerance of the two cultivars by showing enhanced antioxidant activity which resulted in reduced membrane damage and hence improved growth. According to the results obtained, the adverse effects of salt stress on maize plants can partly be alleviated with application of Zn (II)-HEDTA chelates. It is concluded that the application of Zn (II) HEDTA to maize plants grown in salt conditions leads to the increase of antioxidant compounds and maize tolerance.展开更多
BiFe1-xCoxO3 (x = 0, 0.03, 0.05 and 0.1) symbolic as (BFO, BF3CO, BF5CO and BF10CO) in powder form has been prepared by sol-gel technique using ethylenediamine tetraacetic acid (EDTA) as a chelating agent. X-ray diffr...BiFe1-xCoxO3 (x = 0, 0.03, 0.05 and 0.1) symbolic as (BFO, BF3CO, BF5CO and BF10CO) in powder form has been prepared by sol-gel technique using ethylenediamine tetraacetic acid (EDTA) as a chelating agent. X-ray diffraction (XRD) and FTIR analysis showed rhombohedra distorted BiFeO3 structure with compressive lattice distortion induced by the Co substitution at Fe sites. The transmission electron microscope (TEM) shows irregular particles. The additive of cobalt oxide has led to grains refining giving the following crystallite sizes of 18 nm for BF5Co. The scanning electron microscope (SEM) study reveals that the samples morphology shows relatively uniform grain size distribution. The dielectric properties of BiFeO3 nano-particles in the frequency range of 1 up to 5 MHz at RT revealed that the A.C. conductivity of the prepared samples reaches its maximum value in BF5CO. By decreasing BiFeO3 particle size as a result of doping with different Co ion concentrations, an enhancement in magnetization and a simultaneous suppression in current leakage occurred. The remnant magnetization Mr of BiFe1-xCoxO3 (x = 0, 0.03, 0.05, 0.1) ceramics significantly enhanced, which provides potential applications in information storage.展开更多
Wurtzite hexagonal ZnO semiconductor nano-rods (NRs) thin films were grown on silicon substrates and silver wire with diameter equal 68 nm. Sol gel (SG) and aqueous chemical growth (ACG) methods by two steps of prepar...Wurtzite hexagonal ZnO semiconductor nano-rods (NRs) thin films were grown on silicon substrates and silver wire with diameter equal 68 nm. Sol gel (SG) and aqueous chemical growth (ACG) methods by two steps of preparation (seed layers and nano-rod growth) are used for samples preparation. The structural and morphological properties are evaluated using X-ray diffraction (XRD) and scanning electron microscope (SEM). The proposed iron ion sensor has shown good linearity for a wide concentration range from 0.078 M/L to 0.26 M/L of iron ions. The results show that the electrode is highly sensitive to iron ions with a slope around 47.8 mV/decade with a regression coefficient R2 = 0.96.展开更多
The structural, dielectric and magnetic properties of pure and Fe-Co co-doped Ba0.9Sr0.1TiO3, (Ba(1-x)SrxTiO3, where (x = 0.10) and (Ba0.9Sr0.1Ti(1-x-y)FexCoyO3), where (x = 0.1, y = 0) and (x = 0 and y = 0.10) and (x...The structural, dielectric and magnetic properties of pure and Fe-Co co-doped Ba0.9Sr0.1TiO3, (Ba(1-x)SrxTiO3, where (x = 0.10) and (Ba0.9Sr0.1Ti(1-x-y)FexCoyO3), where (x = 0.1, y = 0) and (x = 0 and y = 0.10) and (x = 0.5, y = 0.5) in powder form, abbreviated as (BST) and (BST10FO), (BST10CO) and (BST5F5CO), respectively were prepared by a modified sol gel technique. Crystallization, surface morphology and electrical behavior of BST are improved by Fe3+ and Co2+ ions with optimized grain size. Phase identification by using X-ray diffraction and surface morphology will be studied by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM). Phase identification by using X-ray diffraction and surface morphology evaluation by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM) will be studied. The nano-scale presence and the formation of the tetragonal perovskite phase as well as the crystallinity were detected using the mentioned techniques. The dielectric properties of the prepared samples have been investigated as a function of temperature and frequency. The dielectric measurements are carried out in the frequency range of 42 Hz - 1 MHz, at temperature ranging between 25°C and 250°C. The results showed an abrupt decrease in the dielectric permittivity by increasing the frequency range. The magnetic hysteresis loop confirmed enhancement in the magnetization properties by co-doping with Fe3+-Co2+ ions. An increase in the saturation of the magnetization at room temperature was detected by decreasing the crystallite sizes of the prepared samples.展开更多
The present work aims at studying the effect of Ultra-Violet/Ozone (UV/O3) irradiation of cotton fabrics on their interaction with chitosan/citric acid based formulation and, the onset of this on the ability of treate...The present work aims at studying the effect of Ultra-Violet/Ozone (UV/O3) irradiation of cotton fabrics on their interaction with chitosan/citric acid based formulation and, the onset of this on the ability of treated fabrics to remove heavy metal ions from their aqueous solutions. To achieve the goal, the cotton fabrics were preirradiated for 90 minutes using UV/O3 as radiation source. The irradiated and the unirrdadiated cotton fabrics were submitted to finishing formulation consisting essentially of chitosan as a finishing agent and citric acid as crosslinking agent in combination with sodium hypophosphite (SHP) as a catalyst. Finishing formulation containing different concentrations of chitosan (0 - 4) along with citric acid (8 g/l) and SHP (4 g/l) were used and the interaction of chitosan with the cotton fabric was assessed through nitrogen measurement. The preirradiated and chemically finished fabrics vis-à-vis the unirrdadiated fabrics were examined for metal ion removal. Results conclude that the preirradiated cotton fabrics exhibit higher nitrogen content than the unirrdadiated fabrics. The same holds true for heavy metal removal, exemplified by Zn2+ and Cd2+ ions from their aqueous solutions. That is, preirradiated fabrics containing chitosan display higher percent heavy metal removal than their unirrdadiated mates.展开更多
In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount significance.In the curre...In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount significance.In the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on SEM images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm MB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher charge carriers' separation(Cu^(2+)+ e-→ Cu^(+), La^(3+)+ e-→ La^(2+)), oxygen vacancies, full anatase phase structure as well as the wide range of visible light absorption.展开更多
Background:Growth abnormalities are uniquely associated with autism spectrum disorders(ASD);however,the extent to which growth abnormalities are present has hardly been investigated.The current study aims to compare t...Background:Growth abnormalities are uniquely associated with autism spectrum disorders(ASD);however,the extent to which growth abnormalities are present has hardly been investigated.The current study aims to compare the differences in anthropometric parameters in a group of autistic Egyptian children and the healthy normal population.Methods:We recruited 100 children with ASD from the Outpatient Clinic for"Autistic Children"at the Medical Research Hospital of Excellence,National Research Centre in Cairo,Egypt.They were diagnosed by DSM-IV criteria of the American Psychiatric Association,Autism Diagnostic Interview-Revised,and Childhood Autism Rating Scale.Of these children at age of 3-10 years,71 were males and 29 females.Eight anthropometric parameters were assessed in view of data of the healthy Egyptians of pertinent sex and age.Results:Weight and body mass index increased because of a signifi cant increase in subcutaneous fat thickness.This tendency with a probable decrease in muscle mass was more evident in male or in older children,likely resulting from sedentary life style and food selectivity.Conclusions:The Z head circumference score and its variance signifi cantly increased especially in males or older children,suggesting the relative overgrowth of the brain in a substantial percentage of Egyptian children with autism.We concluded that increased fat composition in Egyptian autistic children with decreased muscle mass necessitates tailoring a specially designed food supplementation program to ameliorate the severity of autism symptoms.展开更多
文摘The volcano-sedimentary succession around Wadi Zaghra in Sinai, at the northernmost segment of the Arabian Nubian Shield, comprises volcanic rocks interbedded with rather immature sediments. The succession is dominated by intermediate to silicic volcanics of medium-to high-K calc-alkaline affinity. It is divided into two units, the lower unit includes intermediate rocks and dacites interbedded with graywackes, semi-pelites and pelites and topped by polymict conglomerates. This unit is subjected to folding and regional metamorphism(up to garnet zone) and is intruded by quartz diorite-granodiorite inducing, locally, low-pressure contact thermal metamorphism. The unmetamorphosed upper unit encompasses acid volcanics intercalated with litharenite, sublitharenite and minor arenite. The rhyolites of this unit pertain to the highly fractionated granites and are characterized by an agpaitic index(NK/A) ranging from 0.87 to 0.96. They may reflect either extensive interaction of subduction-related magmas with the continental crust or a change in the tectonic regime. The present lithological and geochemical characteristics of the studied sediments together with available zircon ages indicate rather distal provenance of their detritus. This detritus comprises fluvial-alluvial sediments accumulated in the intermontane basins, which are half-grabens or tilted fault blocks. The tectonic setting of the depositional basins is active continental margin and continental island arcs. Geochemical patterns of the Zaghra volcano-sedimentary succession indicate their correlation with the Dokhan Volcanics-Hammamat Clastics sequence of the Eastern Desert of Egypt. Also, the Zaghra volcanics display geochemical similarities with those exposed in Sinai, at the Rutig, Ferani and Iqna Shar'a areas. The Zaghra succession is dated as Ediacaran but is not related either to the ensimatic island arc assemblage or to the rift-related assemblage formed during the early stages of the break-up of Rodinia as previously thought.
文摘Objective: To investigate the possible protective and/or therapeutic potentials of Dunaliella salina(D. salina) biomass, its carotenoid and polar fractions on cardiac dysfunction associated with D-galactose(D-GAL) induced aging in rats. Methods: Aging associated cardiac dysfunction was induced in rats by injection of D-GAL(200 mg/kg; i.p) for 8 weeks. D-GAL injected rats were treated with two regimens; protective regimen where D. salina biomass(250 mg/kg), its carotenoid(250 μg/kg) and polar(250 μg/kg) fractions were given orally for two weeks concurrently with D-GAL injection as well as treatment regimen where the three treatments were given orally for 28 consecutive days after D-GAL injection. Results: D-GAL injection for 8 weeks was accompanied with dramatic electrocardiographic changes as well as profound elevation in serum levels of homocysteine, creatinine kinase isoenzyme and lactate dehydrogenase in addition to the reduction of the cardiac content of glucose trasporter 4. D-GAL also induced reduction in cardiac superoxide dismutase activity and elevation of inducible nitric oxide synthetase and interleukin-6. On the other hand, oral administration of D. salina carotenoid fraction as well as the total biomass significantly attenuated the D-GAL-induced disturbances in the above mentioned parameters where the protective regimen appeared more successful in controlling the manifestations of cardiac dysfunction. The histopathological examination further emphasized the promising results. Besides, the HPLC analysis of the carotenoid fraction of D. salina revealed the presence of 2.31%. salina carotenoid fraction as well as the total biomass amelior β-carotene. Conclusions: Date D-GAL-induced aging associated cardiac dysfunction which is attributed to the potent antioxidant activity of β-carotene.
基金the financial support of the Science and Engineering Research Board for the EPMA national facility(IRPHA Grant No.IR/S4/ESF-16/2009 and core research Grant No.CRG/2019/000812)at the Department of Earth Sciences,IIT Bombay(India)。
文摘The Sa'al Metamorphic Complex(SMC;southern Sinai)encompasses the oldest arc rocks in the Arabian–Nubian Shield,comprising two non-consanguineous metavolcanic successions(the Agramiya Group and the Post-Ra'ayan Formation)separated by the metasediments of the Ra'ayan Formation.It experienced three distinct deformational events(D_(1)–D_(3))and two low-medium grade regional metamorphic events(M_1–M_(2)).The Agramiya Group and the Ra'ayan Formation experienced all tectonometamorphic events(D_1–D_(3)and M_(1)–M_(2)),whereas the Post-Ra'ayan volcanic rocks were only affected by the D_(3)and M_(2)events.D_(1)is an extensional event and is connected to the late Rodinia break-up(~Tonian;900–870 Ma).The M_(1)metamorphism variably affected the older Agramiya Group,the rhyolitic tuffs experiencing lower to upper greenschist facies conditions and the basic and intermediate volcanic rocks undergoing amphibolite facies metamorphism.The Ra'ayan Formation metasediments experienced upper greenschist to amphibolite facies metamorphism.The upper greenschist facies M_(2)affected the youngest Post-Ra'ayan volcanic rocks and other stratigraphic successions.The compressive D_(2)and D_(3)events were coeval with the accretion of dismembered terranes in the assembly of Gondwana.D_(2)can be linked to the Tonian–Cryogenian arc-arc assembly(~880–760 Ma;in Elat and Sinai),whereas D_(3)and the accompanying M_(2)is constrained to 622–600 Ma(Ediacaran).
文摘Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)method.The temperature was increased to avoid the bubbles and cracks which may be formed during the preparation of the ingot material.We have started with the flux higher than the normal to avoid the bubbles and make good treatment for the solid-liquid interface.The structures of both Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)were studied by using x-ray diffraction(XRD).Optical properties for C12A7 and Y-C12A7 single crystals have been studied in order to determine the optical parameters such as optical energy gap(Eg),refractive index n,oscillating energy(Eo),dispersion energy(Ed),volume energy loss function(VELF),and surface energy loss function(SELF).Finally,a new result for these samples is that the third-order nonlinear optical susceptibility(χ(3))was determined.The results have been discussed with effect of Y-doping on the C12A7 single crystals for optical and industrial applications.
文摘Zinc (Zn (II) HEDTA) was used to determine their effect on salt-induced damages in maize plants. The aim of this study was to investigate the antioxidant capacity and the levels of enhanced total phenolic (TPC), total flavonoid (TFC) contents and their antioxidant activity in leaves of two maize cultivars Single cross 10 (SC10) and Single cross 162 (SC162) grown in two levels of salinity 0.00 and 100 mmol in response to 20 μmol Zn (II) HEDTA foliar spray treatments. Significant differences (P ≤ 0.05) in amounts of TPC ranged from (2.55 to 4.62 mg/gdw as Gallic) in Single cross 10 (SC10) and from (2.53 to 4.38 mg/gdw as Gallic) in Single cross 162 (SC162), TFC (ranged 1.53 to 2.41 mg/gdw as qurestien) in Single cross 10 (SC10) and from (1.28 to 2.41 mg/gdw as qurestien) in Single cross 162 (SC162) among all treated plants were observed. The levels of their compounds increase related to foliar spraying of Zn (II) HEDTA. A significant positive correlation between TPC, TFC and DPPH scavenging activity and iron chelating activity was observed which shows that phenolic compounds were involved in the mechanism of salt tolerance of the two cultivars by showing enhanced antioxidant activity which resulted in reduced membrane damage and hence improved growth. According to the results obtained, the adverse effects of salt stress on maize plants can partly be alleviated with application of Zn (II)-HEDTA chelates. It is concluded that the application of Zn (II) HEDTA to maize plants grown in salt conditions leads to the increase of antioxidant compounds and maize tolerance.
文摘BiFe1-xCoxO3 (x = 0, 0.03, 0.05 and 0.1) symbolic as (BFO, BF3CO, BF5CO and BF10CO) in powder form has been prepared by sol-gel technique using ethylenediamine tetraacetic acid (EDTA) as a chelating agent. X-ray diffraction (XRD) and FTIR analysis showed rhombohedra distorted BiFeO3 structure with compressive lattice distortion induced by the Co substitution at Fe sites. The transmission electron microscope (TEM) shows irregular particles. The additive of cobalt oxide has led to grains refining giving the following crystallite sizes of 18 nm for BF5Co. The scanning electron microscope (SEM) study reveals that the samples morphology shows relatively uniform grain size distribution. The dielectric properties of BiFeO3 nano-particles in the frequency range of 1 up to 5 MHz at RT revealed that the A.C. conductivity of the prepared samples reaches its maximum value in BF5CO. By decreasing BiFeO3 particle size as a result of doping with different Co ion concentrations, an enhancement in magnetization and a simultaneous suppression in current leakage occurred. The remnant magnetization Mr of BiFe1-xCoxO3 (x = 0, 0.03, 0.05, 0.1) ceramics significantly enhanced, which provides potential applications in information storage.
文摘Wurtzite hexagonal ZnO semiconductor nano-rods (NRs) thin films were grown on silicon substrates and silver wire with diameter equal 68 nm. Sol gel (SG) and aqueous chemical growth (ACG) methods by two steps of preparation (seed layers and nano-rod growth) are used for samples preparation. The structural and morphological properties are evaluated using X-ray diffraction (XRD) and scanning electron microscope (SEM). The proposed iron ion sensor has shown good linearity for a wide concentration range from 0.078 M/L to 0.26 M/L of iron ions. The results show that the electrode is highly sensitive to iron ions with a slope around 47.8 mV/decade with a regression coefficient R2 = 0.96.
文摘The structural, dielectric and magnetic properties of pure and Fe-Co co-doped Ba0.9Sr0.1TiO3, (Ba(1-x)SrxTiO3, where (x = 0.10) and (Ba0.9Sr0.1Ti(1-x-y)FexCoyO3), where (x = 0.1, y = 0) and (x = 0 and y = 0.10) and (x = 0.5, y = 0.5) in powder form, abbreviated as (BST) and (BST10FO), (BST10CO) and (BST5F5CO), respectively were prepared by a modified sol gel technique. Crystallization, surface morphology and electrical behavior of BST are improved by Fe3+ and Co2+ ions with optimized grain size. Phase identification by using X-ray diffraction and surface morphology will be studied by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM). Phase identification by using X-ray diffraction and surface morphology evaluation by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM) will be studied. The nano-scale presence and the formation of the tetragonal perovskite phase as well as the crystallinity were detected using the mentioned techniques. The dielectric properties of the prepared samples have been investigated as a function of temperature and frequency. The dielectric measurements are carried out in the frequency range of 42 Hz - 1 MHz, at temperature ranging between 25°C and 250°C. The results showed an abrupt decrease in the dielectric permittivity by increasing the frequency range. The magnetic hysteresis loop confirmed enhancement in the magnetization properties by co-doping with Fe3+-Co2+ ions. An increase in the saturation of the magnetization at room temperature was detected by decreasing the crystallite sizes of the prepared samples.
文摘The present work aims at studying the effect of Ultra-Violet/Ozone (UV/O3) irradiation of cotton fabrics on their interaction with chitosan/citric acid based formulation and, the onset of this on the ability of treated fabrics to remove heavy metal ions from their aqueous solutions. To achieve the goal, the cotton fabrics were preirradiated for 90 minutes using UV/O3 as radiation source. The irradiated and the unirrdadiated cotton fabrics were submitted to finishing formulation consisting essentially of chitosan as a finishing agent and citric acid as crosslinking agent in combination with sodium hypophosphite (SHP) as a catalyst. Finishing formulation containing different concentrations of chitosan (0 - 4) along with citric acid (8 g/l) and SHP (4 g/l) were used and the interaction of chitosan with the cotton fabric was assessed through nitrogen measurement. The preirradiated and chemically finished fabrics vis-à-vis the unirrdadiated fabrics were examined for metal ion removal. Results conclude that the preirradiated cotton fabrics exhibit higher nitrogen content than the unirrdadiated fabrics. The same holds true for heavy metal removal, exemplified by Zn2+ and Cd2+ ions from their aqueous solutions. That is, preirradiated fabrics containing chitosan display higher percent heavy metal removal than their unirrdadiated mates.
文摘In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount significance.In the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on SEM images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm MB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher charge carriers' separation(Cu^(2+)+ e-→ Cu^(+), La^(3+)+ e-→ La^(2+)), oxygen vacancies, full anatase phase structure as well as the wide range of visible light absorption.
文摘Background:Growth abnormalities are uniquely associated with autism spectrum disorders(ASD);however,the extent to which growth abnormalities are present has hardly been investigated.The current study aims to compare the differences in anthropometric parameters in a group of autistic Egyptian children and the healthy normal population.Methods:We recruited 100 children with ASD from the Outpatient Clinic for"Autistic Children"at the Medical Research Hospital of Excellence,National Research Centre in Cairo,Egypt.They were diagnosed by DSM-IV criteria of the American Psychiatric Association,Autism Diagnostic Interview-Revised,and Childhood Autism Rating Scale.Of these children at age of 3-10 years,71 were males and 29 females.Eight anthropometric parameters were assessed in view of data of the healthy Egyptians of pertinent sex and age.Results:Weight and body mass index increased because of a signifi cant increase in subcutaneous fat thickness.This tendency with a probable decrease in muscle mass was more evident in male or in older children,likely resulting from sedentary life style and food selectivity.Conclusions:The Z head circumference score and its variance signifi cantly increased especially in males or older children,suggesting the relative overgrowth of the brain in a substantial percentage of Egyptian children with autism.We concluded that increased fat composition in Egyptian autistic children with decreased muscle mass necessitates tailoring a specially designed food supplementation program to ameliorate the severity of autism symptoms.