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Synthesis of M–Nd doped Fe3O4 nanoparticles (M = Co, Ce, Cr, Ni) with tunable magnetic properties
M. Yousefi, P. Alimard
Bulletin of the Chemical Society of Ethiopia , 2013,
Abstract: Magnetic nanoparticles were prepared by the aqueous co-precipitation method. The magnetic nanoparticles obtained were characterized systematically through the use of an X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR) and a vibrating sampling magnetometer (VSM). The results revealed that the magnetic nanoparticles were spherical shaped with inverse spinel structure. The size of Fe3O4 and Nd-Co doped Fe3O4 magnetic nanoparticles were approximately 15 nm. Magnetic measurement revealed that the nanoparticles were super paramagnetic at room temperature. It was found that the magnetic response of the Fe3O4 increased when it was doped with Nd3+ and Co2+. However, the magnetic response of the Fe3O4 decreased when it was doped with Nd3+ or Ce3+ or Cr3+or Ni2+. KEYWORDS: Fe3O4, Magnetic nanoparticles, Superparamagnetic, Magnetite, Fe3O4 doped Bull. Chem. Soc. Ethiop. 2013, 27(1), 49-56. DOI: http://dx.doi.org/10.4314/bcse.v27i1.5
THE EFFICIENCY OF ELECTROCOAGULATION PROCESS USING ALUMINUM ELECTRODES IN REMOVAL OF HARDNESS FROM WATER
M. Malakootian ? N. Yousefi
Iranian Journal of Environmental Health Science & Engineering , 2009,
Abstract: There are various techniques for removal of water hardness each with its own special advantages and disadvantages. Electrochemical or electrocoagulation method due to its simplicity has gained a great attention and is used for removal of various ions and organic matters. The aim of the present study was to investigate the efficiency of this technique in removal of water hardness under different conditions. This experimental study was performed using a pilot plant. The applied pilot was comprised of a reservoir containing aluminum sheet electrodes. The electrodes were connected as monopolar and a power supply was used for supplying direct electrical current. Drinking water of Kerman (southeast of Iran) was used in the experiments. The efficiency of the system in three different pH, voltages and time intervals were determined. Results showed the efficiency of 95.6% for electrocoagulation technique in hardness removal. pH and electrical potential had direct effect on hardness removal in a way that the highest efficiency rate was obtained in pH=10.1, potential difference of 20 volt and detention time of 60 minutes. Considering the obtained efficiency in the present study, electrocoagulation technique may be suggested as an effective alternative technique in hardness removal.
Effect of Probiotic Thepax and Saccharomyces cerevisiae Supplementation on Performance and Egg Quality of Laying Hens
M. Yousefi,K. Karkoodi
International Journal of Poultry Science , 2007,
Abstract: An experiment was conducted to evaluate the effects of different levels of probiotic Thepax (0.05, 0.1 and 0.15 %) and yeast (Saccharomyces cerevisiae) (0.05, 0.1 and 0.15 %) on performance and egg quality of laying hens. Two hundred and ten 63 wk of age Hy-line W-36 hens were used. The birds were assigned seven treatment groups in a randomized complete block design, with three replicates each with ten hens. The hens performance and egg parameters were evaluated on the three 28-d periods. The results of body weight changes, feed intake, feed conversion ratio, egg production, egg weight, shell percent and albumin weight did not indicate any treatment effect (P>0.05). Shell weight, shell thickness, yolk weight and yolk cholesterol were significantly (P=0.05) different among treatment groups. Yolk cholesterol was lower for 3, 5, 6 and 7th treatments compared to the control. The use of probiotic and Saccharomyces cerevisiae were not affected by production. But, egg quality did improved from 63 to 75 weeks of age.
Synthesis of M–Nd doped Fe3O4 nanoparticles (M = Co, Ce, Cr, Ni) with tunable magnetic properties
M. Yousefi,P. Alimard
Bulletin of the Chemical Society of Ethiopia , 2013,
Abstract: Magnetic nanoparticles were prepared by the aqueous co-precipitation method. The magnetic nanoparticles obtained were characterized systematically through the use of an X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR) and a vibrating sampling magnetometer (VSM). The results revealed that the magnetic nanoparticles were spherical shaped with inverse spinel structure. The size of Fe3O4 and Nd-Co doped Fe3O4 magnetic nanoparticles were approximately 15 nm. Magnetic measurement revealed that the nanoparticles were super paramagnetic at room temperature. It was found that the magnetic response of the Fe3O4 increased when it was doped with Nd3+ and Co2+. However, the magnetic response of the Fe3O4 decreased when it was doped with Nd3+ or Ce3+ or Cr3+or Ni2+.DOI: http://dx.doi.org/10.4314/bcse.v27i1.5
Study of Efficacy of Disinfecting Effects of the Deconex 50 AF And Glutaraldehyd on Bacteria Isolated From Surgical Room Of Hospitals of Hamadan
R Yousefi Mashouf,M Nazari
Iranian Journal of Public Health , 2007,
Abstract: Background: Nosocomial infection is one of the most important and problematic difficult in the educational hospital. There are different points of view about applying of disinfectant material in surgical rooms. According to the both side effect and health care financial, selecting the best material to disinfections is important. Therefore this study has been done to determine of effects of two material including Cidex (glutaraldehyd) and Deconex 50 AF (ammonium quaternary compounds). Methods: In this study 460 samples were collected randomizing from surgical rooms of Mobasher Kashany and Imam Khomeini hospitals of Hamadan. The samples were taken from surfaces and surgical instrument. The first group was the samples that were taken before and after applying Glutaraldehyd. In this group there were 110 samples befor and 110 after doing disinfections. The second group was the samples that were taken before and after applying Deconex 50 AF. The numbers of samples were 120 before and 120 after doing disinfections. There were five days interval between each stage of sampling in this period, the surgical room was active after selecting and the samples were cultured on the specific media and transferred to lab. Then the data were analyzed and compared by SPSS program by computer. Results: The most important bacteria isolated were as follow: Bacillus subtilis, Staphylococcus epidermidis, Enterobacter aeroginosa, Corynebacterium diphteroides and E. coli. This study also indicated that the efficacy of the two solution were significantly different (P= 0.04) before and after disinfections. The disinfections effect of Deconex 50 AF was 73% and Glutaraldehyde was 59%. Acording to the ranking of efficacy, the first is Deconex 50 AF and the second is Glutaraldehyde. Conclusion: Our results showed that Deconex 50 AF was relatively more effective than Glutaradlehyde and also it has less side effect rather than Glutaradlehyde.
Influence of Closure & Non-Closure of the Visceral and Parietal Peritoneum on Post Cesarean Morbidity
Tabasi Z.,Abedzadeh M.,Yousefi M.
Qom University of Medical Sciences Journal , 2010,
Abstract: Background and Objectives: One of the most important issues in promoting mother and child health is reducing the morbidity rate after cesarean section. The aim of this study was to investigate the influence of closure and non-closure of the visceral and parietal peritoneum on post cesarean morbidity in women attending Shabihkhani Maternity Hospital in Kashan, Iran.Methods: This study was conducted with a single blind randomized clinical trial method on 100 parturient women that underwent emergency or elective cesarean section. Patients with previous cesarean section and or abdominal surgery, diseases such as hypertension, diabetes mellitus and premature rupture of membrane and pre operative bleeding, were excluded from this study. Then, the participants were randomly divided into two groups: in one group both peritoneal layers were closed while in the other group, they were not closed. Post operative morbidity including fever, bleeding, post operative pain, analgesic consumption and time of operation were assessed. Data were analyzed with t-tests, and χ2 and a P<0.05 were considered significant.Results: In this study, there were no significant differences between the two groups with respect to age, gestational age, the reason for caesarean section and gravidity, nor were there any differences with respect to the incidence of fever or bleeding and was similar between the two groups, but there was a significant difference between the two groups regarding to feeling of severe pain (P=0.0003), analgesic consumption (P=0.0003) and time of operation (P=0.004). In the non-closure group, dose of analgesic drugs, pain severity and time of operation were less than those of the other group.Conclusion: The Findings showed that non-closure of peritoneal layers as a shorter and simpler procedure has no influence on increasing post cesarean morbidity. Therefore, due to maternal health promotion and early neonatal breastfeeding, non closure of peritoneal layers is recommended.Keywords: Caesarean Section; Pain; Hemorrhage; Bleeding; Peritoneal Clousure.
Pyrolytic carbon film deposit as an electrochemical interface.
M. Hadi,A. Rouhollahi,M. Yousefi
Carbon : Science and Technology , 2009,
Abstract: A pyrolytic carbon (PC) film was grown on planar substrate (graphite rods) by chemical vapor deposition from gaseous feed of methane using a vertical hot-wall deposition reactor. Scanning electron microscopy was used to study the surface structure. The PC film was also characterized by cyclic voltammetry technique to evaluate the background current, stability and the electrochemical response using ascorbic acid, Co(phen)32+/3+ and Fe(CN)6 3-/4- redox couplesand compared to glassy carbon (GC) electrode. High degree of electrochemical activity and the enhanced signal to background (S/B) ratio demonstrated that the PC film might be an attractive electrode material for electroanalytical measurements.
Broadband Experimental Characterization of Artificial Magnetic Materials Based on a Microstrip Line Method
Leila Yousefi;Hussein Attia;Omar M. Ramahi
PIER , 2009, DOI: 10.2528/PIER08121904
Abstract: A broadband method is introduced to measure the effective constitutive parameters of artificial magnetic materials. The method is based on the microstrip line topology, thus making it easy to retrieve the constitutive parameters over a wide band of frequencies. To demonstrate the effectiveness of this method, artificial magnetic materials with Fractal Hilbert inclusions are fabricated and characterized. Good agreement between the experimental and numerical simulation results verifies the accuracy of the proposed method.
The Role of Hemolysis in Inducing Jaundice in the Newborns with G6PD Deficiency
J Yousefi,M Mirzadeh,A Malek
Iranian Journal of Pediatrics , 2006,
Abstract: Background: Jaundice is a common disorder in neonates and G6PD deficiency is one of its known etiologic factors that could result in kernicterus. This study was done to determine (1) incidence of this enzyme deficiency in icteric newborns and (2) the role of hemolysis in inducing jaundice in G6PD deficient neonates. Methods: This is a 3-year cross-sectional study performed on 505 icteric newborn infants admitted to 22e Bahman hospital in Mashad. G6PD activity was measured qualitatively in the patients. The case group consisted of 34 newborns with G6PD deficiency and the control group included also 34 neonates without this enzyme-defect. In addition to routine laboratory tests, hemolysis indicators were also evaluated in both groups and data were analyzed statistically with SPSS. Findings: The incidence of G6PD deficiency was 6.7% (85% male and 15% female). Mean level of total bilirubin was significantly higher in case group (22.73mg/dl vs 19.25mg/dl in control group with pv<0.05). In each group hemolysis was proved to exist in only 2 neonates and Coombs test was negative in all of the patients. There were no significant differences in the mean level of hematocrit and reticulocyte counts between the two groups (pv<0.05). Conclusions: With respect to the high incidence of G6PD deficiency in this study (6.7%) and significant incidence in females, measurement of G6PD activity should be recommended in all newborns with jaundice regardless of sex. Hemolysis plays a minor role in inducing jaundice in these newborns and most of them have nonhemolytic jaundice, so that exchange transfusion should be done according to the same indications of other nonhemolytic icterus cases. Because of higher level of serum bilirubin in G6PD deficient neonates, phototherapy must be started early and with lower levels of serum bilirubin.
Effect of Waste Water on Heavy Metal Accumulation in Hamedan Province Vegetables
M. Cheraghi,B. Lorestani,N. Yousefi
International Journal of Botany , 2009,
Abstract: The objective of this research was to elucidate the effect of waste water on heavy metal concentration in vegetables. To this purpose a region fertilized with waste water (Najafi Boolvar, Hamedan, Iran) was chosen as a polluted area and a region without any waste water pollution (Heydareh, Hamedan, Iran) as a control area. Eight kinds of vegetables were collected from both areas, separately and after preparing, Pb, Zn, Cu and Mn concentrations of them, were measured by using the atomic absorption spectrophotometer. Present results showed that concentration of some heavy metals in vegetables grown in Najafi Boolvar was several times as high as that in Heydareh. According to the results of present study, waste water have special problems for vegetables and thus for human health, because of ability of accumulating heavy metals in soil and biological accumulation of these elements in food chain.
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