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1.
Appl Radiat Isot ; 208: 111281, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38554688

ABSTRACT

In the present study, a facile nano-sized gamma alumina was synthesized and then examined for immobilization of cobalt and cesium ions individually from aqueous solutions. The comprehensive analysis of functional groups, phase composition, surface morphology and sorption characteristics of the synthesized nano-sized ϒ alumina was executed. It was deduced that acquired material was low-crystalline with a high elimination efficacy towards the concerned cations under slightly alkali and acidic conditions. Time-transient elimination scrutiny was executed and cobalt elimination rate was found relatively faster than cesium cations. Equilibrium sorption examinations confirmed that the sorption is proceeding via two diverse sites on the scavenger surface. Cobalt and cesium elimination is a spontaneous endothermic reaction of increased chaos. The attained results proved the high proficiency of the synthesized scavenger in the cations immobilization.

2.
Sci Rep ; 13(1): 21570, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38062090

ABSTRACT

Herein, barium tungstate BaWO4 nanocrystals were chemically prepared and then estimated as inorganic sorbent material to eliminate the radioactive cobalt and europium from the waste stream. The characterization of BaWO4 nanocrystals is completed over several analytical techniques. TEM and SEM images show the formation of sphere-shaped BaWO4 structures in the nanoscale range. Also, XRD and FTIR revealed the successful preparation of BaWO4. Optimum factors affected by the sorption process are determined using batch mode. Sorption equilibrium was achieved after 60 min with the initial concentration of metal ion at 100 mg/L and at optimum pH five for both radionuclides, respectively. The different kinetic models are applied. The obtained data shows that the sorption process followed a pseudo-second order. The sorption capacity for 60Co at pH of 5 and 25 °C is 310.6 mg g-1, and 152+154Eu is 409.9 mg g-1. The thermodynamic studies illustrated that the sorption process was spontaneous and endothermic.

3.
BMC Chem ; 17(1): 149, 2023 Nov 04.
Article in English | MEDLINE | ID: mdl-37925482

ABSTRACT

Carbon-coated ZrO2/Mn-Mg-Zn ferrites nanostructures (CZ-FN) have been prepared as a new inorganic sorbent to remove Cs (I) and Sr (II) from a waste stream. Adsorption of Cs (I) and Sr (II) has been implemented considering different noteworthy parameters, for example, shaking time and the optimum time achieved high adsorption capacity of both ions [103 and 41 mg/g for Sr (II) and Cs (I)] was found 30 min. Also, the impact of pH values was studied; the best pH value for the adsorption process is pH 6. The adsorption saturation capacity of CZ-FN is 420.22 and 250.45 mg/g for strontium and cesium, respectively. The solubility percentage of CZ-FN was calculated utilizing diverse molarities from HNO3, HCl, and NaOH as eluents, the obtained data reveals an increase in the solubility percentage with more increase in the molarity of the eluents. The elevation in the solubility percentage follows the following order; HNO3 < HCl < NaOH. The kinetic studies were applied using the nanolinear form of different kinetic models; it was found that the adsorption process obeys the nonlinear pseudo-second-order. According to equilibrium studies, the Langmuir model has been more accurate than the Freundlich model for adsorption in the case of binary systems. The values of Di for the strontium and cesium are 10-10 m2/s, which displays the chemisorption nature of this process. The greatest values of the desorption process for the strontium and cesium are 96.87% and 94.43 by 0.3 M of HNO3. This indicated that the carbon-coated ZrO2/Mn-Mg-Zn ferrites could be regenerated and recycled to remove strontium and cesium ions from waste streams.

4.
Sci Rep ; 13(1): 5856, 2023 Apr 11.
Article in English | MEDLINE | ID: mdl-37041256

ABSTRACT

Reclaimable adsorbents have an essential role in removing radionuclides from waste streams. Herein, zinc ferrite-humic acid ZFO/HA nanocomposite was synthesized for effective cesium and barium adsorption. The prepared ZFO/HA nanocomposite was analyzed using analytical techniques including XRD, FTIR, EDX, and SEM. From kinetic studies, the mechanism adsorption process follows the second model. The isotherm studies clarified that the Langmuir model fit the adsorption of both ions onto the prepared sample, and the monolayer capacities are equal to 63.33 mg/g and 42.55 mg/g for Ba(II) and Cs(I), respectively. The temperature parameter was also studied, and the adsorption reaction was spontaneous and endothermic. The maximum separation between two ions was achieved at pH 5 (αCs/Ba = 3.3).

5.
J Colloid Interface Sci ; 607(Pt 1): 111-124, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34492348

ABSTRACT

Herein, a novel adsorbent based on carbon-modified zirconia/spinel ferrite (C@ ZrO2/Mn0.5Mg0.25Zn0.25Fe2O4) nanostructures were chemically prepared to remove 60Co and 152+154Eu radionuclides from liquid media using batch experiments. The XRD pattern confirms the successful preparation of the C@ZrO2/MnMgZnFe2O4 composite. Also, SEM and TEM images confirmed that the composite owns a heterogeneous morphology in the nanoscale range. The optical band gap value of Mn0.5Mg0.25Zn0.25Fe2O4, ZrO2, and the composite samples was 1.45, 2.38, and 1.54 eV, respectively. Many parameters have been studied as the effect of time, solution pH, and initial ion concentration. The kinetics models for the removal process of 152+154Eu and 60Co radionuclides were studied. The second-order kinetic equation could describe the sorption kinetics for both radionuclides. The Langmuir monolayer capacity for 60Co was 82.51 mg/g and for 152+154Eu was 136.98 mg/g. The thermodynamic parameters such as free energy ΔGo, the enthalpy ΔHo, and the entropy ΔSo were calculated. The results indicated that the sorption process has endothermic nature for both two radionuclides onto C@ZrO2/MnMgZnFe2O4 composite.


Subject(s)
Nanostructures , Water Pollutants, Chemical , Adsorption , Aluminum Oxide , Carbon , Cobalt , Europium , Ferric Compounds , Hydrogen-Ion Concentration , Kinetics , Magnesium Oxide , Solutions , Temperature , Thermodynamics , Water Pollutants, Chemical/analysis , Zirconium
7.
Appl Radiat Isot ; 164: 109278, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32819509

ABSTRACT

Adsorption of radioactive europium from aqueous solution was achieved using activated carbon - epoxy composite. The preparation of activated carbon - epoxy composite was reported using gamma radiation. The ratio of the activated carbon: epoxy was 50:50 Wt %. Irradiation of the mixture by the dose 20 KGy in gamma cell was performed. The physicochemical properties of the prepared composite were investigated by using different analytical techniques. The obtained results were analyzed using different kinetic models. The sorption kinetic process fitted with the pseudo-second-order model preferably than the pseudo-first-order model. The sorption mechanism was achieved by multi-diffusion steps comprising both film and intra-particle diffusion. The monolayer capacity of the composite was 297.62 mg/g. The thermodynamic parameters were studied. The negative value of ΔG0 and the positive value of ΔH0 revealed the spontaneous and endothermic nature of the sorption process.

8.
Ecotoxicol Environ Saf ; 189: 110013, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31812822

ABSTRACT

This study targeted to investigate the efficacy of a novel nano 2-naphtyl amine6:6-azulene sodium methanesulfonate di sulphonic acid-impregnated zeolite scavenger for simultaneous elimination of Cs+ and Sr2+ ions from binary aqueous systems. Fractal analysis is introduced to assign a fractal dimension and other fractal characteristics necessary for the surface characterization in terms of fractal dimension (Ds) and pre-exponential coefficient (C), which, in theory, are independent tool and sole for each surface. It is found that the Ds value of nano 2-naphtyl amine6:6-azulene sodium methanesulfonate di sulphonic acid-impregnated zeolite of type Y (NAASMS-ZY) is higher than that of nano 2-naphtyl amine6:6-azulene sodium methanesulfonate di sulphonic acid-impregnated zeolite of type X (NAASMS-ZX) and nano 2-naphtyl amine6:6-azulene sodium methanesulfonate di sulphonic acid-impregnated zeolite of type A (NAASMS-ZA) which accordingly, suggests the irregularity of NAASMS-ZY surface and thus demonstrates a large surface area. To increase the scavenge efficacy, effecting parameters on scavenge process were investigated and optimized via the use of adopting Taguchi L16 design of experiments approach. It is found that, the initial metal ions concentration is the most powerful variable, and its value of contribution percentage is up to 33% and 31% for Cs+ and Sr2+, respectively. The kinetic curves and sorption isotherms at 298, 303 and 313 K were obtained, which well fitted to hyperbolic and Langmuir equations, respectively. Thermodynamic parameters demonstrated that the scavenge process was endothermic for both the concerned ions. Our results showed that the novel synthesized NAASMS-ZY is an effective nano-scavenger for cesium and strontium decontamination.


Subject(s)
Cesium/isolation & purification , Strontium/isolation & purification , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Zeolites/chemistry , Cesium/chemistry , Kinetics , Models, Theoretical , Strontium/chemistry , Sulfonic Acids/chemistry , Surface Properties , Thermodynamics , Water Pollutants, Chemical/chemistry , Zeolites/chemical synthesis
9.
Appl Radiat Isot ; 147: 40-47, 2019 May.
Article in English | MEDLINE | ID: mdl-30798204

ABSTRACT

Increasing in the use of various radioactive elements in many applications over the past few decades has accompanied with an increase radioactive waste. Therefore, preparation of Al2O3ZrO2CeO2 nanocomposite material by sol-gel polymeric method is carried out. The nanocomposite material was characterized by some analytical techniques such as Fourier transform infrared (FTIR), Thermograviemtric & differential thermal analysis (TGA & DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Separation of 134Cs and 90Sr/90Y as a fission product present in radioactive waste effluents using the prepared nanocomposite was investigated. The result showed that removal of 94%, 44% and 8.5% for 134Cs, 90Sr and 90Y, respectively. The experimental results are fitted with pseudo-second-order kinetic model. Isotherm models of sorption process are calculated and it can be concluded that the Langmuir model more fitted than Freundlich model. The calculated thermodynamic functions exhibited that sorption behavior of 134Cs and 90Sr ions are spontaneous in nature and the positive value of ΔHo value indicates that the sorption is endothermic. The results demonstrated that the % sorption of 134Cs(I) and 90Sr(II) is sharply decreased in the presence of coexisting ions (Na, Mg and Cr) using nanoparticles of Al2O3 ZrO2CeO2.

10.
Appl Radiat Isot ; 146: 40-47, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30753983

ABSTRACT

Poly (acrylamido-sulfonic acid) polymers have been synthesized using the technique of radical chain polymerization utilizing acrylamide and ammonium persulphate. The polymerization was triggered and controlled using radiation from 1.1 µCi radium source. The polymer sheet was characterized using FTIR, DTA, TG, XRD and SEM. The sorption behavior of the prepared polymer was investigated for 137Cs radionuclide from acid medium (nitric acid). Different parameters such as shaking time and concentrations of HNO3 have been investigated. The removal of 137Cs obeys the pseudo-second-order mechanism. The maximum monolayer capacity of polymer was 139.7 mg/g at room temperature. The thermodynamic parameters such as ΔG°, ΔH° and ΔS° were calculated.

11.
Trop Biomed ; 35(1): 1-9, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-33601771

ABSTRACT

The lifestyles of the indigenous people (Orang Asli) of Peninsular Malaysia who traditionally live close to the forest, put them at higher risk of exposure to zoonotic diseases. Leptospirosis has recently emerged as one of the most important diseases of public health concern. Here, we aimed to obtain a baseline data on the level of Leptospira exposure among the 107 Orang Asli volunteers using a recombinant antigen-based ELISA, previously shown to have sensitivity of ~90.0% in comparison to the microscopic agglutination test (MAT). Among the Orang Asli volunteers in this study, 60.7% had IgM against Leptospira and 57.9% were antiLeptospira IgG positive. Of these seropositive individuals, 29.9% had both anti-Leptospira IgM and IgG antibodies. Age was found to be a significant predictor for exposure to Leptospira (P < 0.05) with the younger Orang Asli population more likely to be tested positive for antiLeptospira IgM. The finding of high Leptospira exposure among the Orang Asli volunteers could be due to their socio-economic practices and dependency on the forest for their livelihood. The rapid and sensitive recombinant antigen-based ELISA used in the study, could possibly complement MAT for the epidemiological surveillance of leptospirosis, especially among the underserved populations.

12.
J Viral Hepat ; 22(8): 665-70, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25496114

ABSTRACT

Little is known about how hepatitis C (HCV) infection affects cognitive function in children. The aim of the study was to assess the impact of HCV infection on cognitive function of children with normal liver functions and their relationships to endogenous IFN-α, IL-6 and TNF-α. IFN-α, IL-6 and TNF-α were measured and the Arabic version of the Stanford-Binet test used to assess cognitive functions in 35 children with HCV infection and 23 controls. Serum levels of IL-6 and IFN-α were significantly higher in patients compared to controls. There was a significant effect on vocabulary, comprehension, and abstract visual reasoning, quantitative reasoning and bead memory tests, as well as total short-term memory and intelligence quotient in patients compared to controls. There was a significant positive correlation between IFN-α and IL-6. Also there were significant negative correlations between IFN-α and Abstract visual reasoning test, Quantitative reasoning test, Bead memory test, Total short-term memory and Intelligence quotient; and between IL-6 and Abstract visual reasoning test, Quantitative reasoning test and Intelligence quotient. There was no significant correlation between TNF-α and any of the cognitive functions. Cytokine levels were not related to demographic characteristics of the patients or viral load (PCR). Children with chronic hepatitis C infection in its early stages showed signs of cognitive impairment, with the memory tasks being mostly affected. There was a significant correlation between endogenous cytokines and cognitive impairment in these children. Further studies are needed to define the effect of successful antiviral treatment.


Subject(s)
Cognition Disorders/epidemiology , Cognition , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/pathology , Interferon-alpha/blood , Interleukin-6/blood , Tumor Necrosis Factor-alpha/blood , Adolescent , Case-Control Studies , Child , Child, Preschool , Cognition Disorders/pathology , Female , Humans , Male
13.
Article in English | MEDLINE | ID: mdl-23983342

ABSTRACT

Crude saponin extracts of five medicinal plants used in the treatment of inflammatory diseases like rheumatoid arthritis, gout and haemorrhoids were screened for anti-inflammatory activity using carrageenan-induced rat paw oedema test. These plants were the whole plant of Schwenkia americana Linn (WSA), the rhizomes of Asparagus africanus Lam (RAA), the leaves of Dichrostachys cinerea Linn (LDC), the stem bark of Ficus iteophylla Miq (BFI) and the leaves of Indigofera pulchra Willd (LIP). A modify traditional method of crude saponins extraction was used to give the following percentage yields: WSA-2.74%, RAA-3.59%, LDC-1.62%, BFI-0.81% and LIP-1.57% respectively. Thin-layer chromatography was used to identify the type of saponins present in the extracts. The acute toxicity study of the crude saponin extracts in mice gave the following intraperitoneal LD50: WSA-471.2mg/kg, RAA- 1264.9mg/kg, LDC-1264.9 mg/kg, BFI-118.3mg/kg and LIP-1264.9 mg/kg respectively. The anti-inflammatory study of the extracts showed statistically significant (P<0.05) decreases in the rat paw-oedema as compared to the control. The percentage inhibitions of the extracts after four hours were as follow: WSA-61%, RAA-55%, LDC-72%, BFI-66% and LIP-40% respectively. These values were found to be comparable to that of ketoprofen-63%. The study showed that the anti-inflammatory properties attributable to these plants may be due to their saponins contents.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Asparagus Plant/chemistry , Fabaceae/chemistry , Ficus/chemistry , Indigofera/chemistry , Phytotherapy , Saponins/therapeutic use , Animals , Anti-Inflammatory Agents/pharmacology , Carrageenan , Edema/chemically induced , Edema/drug therapy , Ketoprofen/pharmacology , Ketoprofen/therapeutic use , Mice , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Plant Structures , Rats , Saponins/pharmacology
14.
Afr J Tradit Complement Altern Med ; 4(3): 257-60, 2007 Feb 16.
Article in English | MEDLINE | ID: mdl-20161886

ABSTRACT

The bioactive ethyl acetate and N-butanol soluble parts of an ethanolic extract of Byrsocarpus coccineus leaves was subjected to column chromatography over silica gel G (60-120 microns) and repeated purification of the flavonoid rich fraction over sephadex LH-20 eluted with methanol led to the isolation of three flavonoid glycosides identified as quercetin 3-O-alpha-arabinoside (I), quercetin (II) and quercetin 3-beta-D-glucoside. Their structures were elucidated by (1)H and (13)C-NMR data and are reported here for the first time in this plant.

15.
Article in English | AIM (Africa) | ID: biblio-1256190

ABSTRACT

The methanolic extract of the roots of Asparagus africanus Lam (Liliaceae) which contains mainly saponins and carbohydrate showed significant analgesic and anti-inflammatory activities (P0.05) in the tail-flick/hot-plate test and egg albumen-induced rat paw oedema tests that were comparable to the test drugs (morphine 20mg/kg and indomethacin 50mg/kg respectively). These results indicate that the extract possesses analgesic and anti-inflammatory properties


Subject(s)
Analgesics , Anti-Inflammatory Agents , Asparagus Plant , Plant Roots
16.
Am J Surg ; 180(5): 343-4, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11137684

ABSTRACT

BACKGROUND: Tremendous technological advances have occurred in pediatric airway management within the past century. Pediatric surgeons have been involved in the technological progress and have also evolved as concerned care-givers. METHODS: A short history reveals a few outstanding physicians who not only contributed to the technological triumphs but also to promoting "high touch." CONCLUSION: Pediatric surgeons must be involved in the rapidly progressing technologies but must not allow high technology to outpace high touch.


Subject(s)
Bronchoscopy , Pediatrics , Specialties, Surgical , Adult , Bronchoscopy/history , Child , Esophagoscopy/history , Fiber Optic Technology , Foreign Bodies/surgery , History, 19th Century , History, 20th Century , Humans , Pediatrics/history , Specialties, Surgical/history , United States
17.
Am J Trop Med Hyg ; 63(5-6): 259-63, 2000.
Article in English | MEDLINE | ID: mdl-11421374

ABSTRACT

Antimicrobial sensitivity tests were performed on four-hundred and ninety-seven bacterial isolates from Sudanese patients with diarrhea or urinary tract infections. Shigella dysenteriae type I and enteropathogenic Escherichia coli showed high resistance rates (percentage of isolates showing antibiotic resistance) against the commonly-used antimicrobial agents: ampicillin, amoxicillin, chloramphenicol, tetracycline, cotrimoxazole, nalidixic acid, sulfonamide, and neomycin, and were completely sensitive to ciprofloxacin. Eighteen resistance patterns against nine antimicrobial agents tested were observed in enteric pathogens. Resistance to ampicillin, amoxicillin, tetracycline, cotrimoxazole, and sulfonamide was the most frequent pattern. The common urinary pathogens, E. coli, Klebsiella pneumoniae, and Proteus mirabilis showed high rates of resistance to ampicillin, amoxicillin, cotrimoxazole, tetracycline, sulfonamide, trimethoprim, streptomycin, and carbenicillin. We recommend that physicians seek updated knowledge of the common antibiotic-sensitivity patterns when starting empirical antibiotic therapy in Sudanese patients with diarrhea or urinary tract infection.


Subject(s)
Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacteria/drug effects , Bacterial Infections/drug therapy , Diarrhea/microbiology , Urinary Tract Infections/microbiology , Bacteria/isolation & purification , Bacterial Infections/epidemiology , Bacterial Infections/microbiology , Ciprofloxacin/pharmacology , Ciprofloxacin/therapeutic use , Drug Resistance, Microbial , Escherichia coli/drug effects , Humans , Microbial Sensitivity Tests , Shigella/drug effects , Sudan/epidemiology
19.
East Afr Med J ; 71(11): 745-6, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7859660

ABSTRACT

Diarrhoea caused by the protozoan parasite Cryptosporidium has been shown in several tropical countries to be an important health problem, particularly in children. Although infection is often associated with contact with animals, it may also occur through person to person transmission and via contaminated water or food. We have undertaken a cross sectional study to determine the prevalence of Cryptosporidium in children with diarrhoea and in their family contacts, and also investigated its occurrence in adult food handlers. Sixteen of 100 children with diarrhoea and none of the controls, were positive for Cryptosporidium. In addition, seven children had one or more sibs with diarrhoea who also excreted Cryptosporidium. None of the food handlers or asymptomatic children were positive. The results confirm earlier findings that Cryptosporidium is an important cause of diarrhoea in children in Sudan, and suggest that intrafamilial spread occurs.


Subject(s)
Carrier State/epidemiology , Cryptosporidiosis/epidemiology , Diarrhea/parasitology , Carrier State/transmission , Case-Control Studies , Child, Preschool , Cross-Sectional Studies , Cryptosporidiosis/transmission , Family , Food Parasitology , Humans , Infant , Population Surveillance , Prevalence , Sudan/epidemiology , Urban Health
20.
Plast Reconstr Surg ; 77(1): 17-28, 1986 Jan.
Article in English | MEDLINE | ID: mdl-3941846

ABSTRACT

In 15 fresh cadavers (30 sides), we studied the two layers of fascia in the temporal region, with particular regard to their blood supply and to their usefulness--together or separately--as microvascular free-tissue autografts. The superficial temporal fascia (temporoparietal fascia, epicranial aponeurosis) lies immediately deep to the hair follicles. It is part of the subcutaneous musculoaponeurotic system and is continuous in all directions with other structures belonging to that layer--including the galea above and the SMAS layer of the face below. The deep temporal fascia (temporalis fascia, investing fascia of temporalis) is separated from the superficial fascia by an avascular plane of loose areolar tissue. It completely invests the superficial aspect of the temporalis muscle down to (but not beyond) the zygomatic arch. It is firmly attached to periosteum all around the margin of the muscles. Below it is attached to the upper border of the zygomatic arch. We found the deep temporal fascia to be supplied solely by the middle temporal artery, a constant branch of the superficial temporal. The middle temporal artery arises 1 to 3 cm below the upper border of the zygomatic arch, runs always superficial to the arch, and enters the deep temporal fascia immediately above that layer's attachment to the zygomatic arch. If the middle temporal vessels are protected, the two layers of temporal fascia can be raised together as a fully vascularized tissue island. This island can be fashioned as a bilobed or a double-layered flap, depending on the manner of dissection. The potential surgical usefulness of these findings is discussed.


Subject(s)
Fascia/anatomy & histology , Head/anatomy & histology , Temporal Arteries/anatomy & histology , Adult , Child , Fascia/blood supply , Fasciotomy , Female , Humans , Surgical Flaps , Temporal Muscle/anatomy & histology , Zygoma/anatomy & histology
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