Table of content

Baghdad Science Journal

مجلة بغداد للعلوم

ISSN: 20788665 24117986
Publisher: Baghdad University
Faculty: Science for Women
Language: Arabic and English

This journal is Open Access

About

A Scientific and Evaluated Journal Published by the College of Science for Women, University of Baghdad
Date of First issue(2004)
No.of Issue per year(4)
No.of papers per issue (25)
No. Of issue published between 2004-2016(50) issue
This Journal publish paper in Arabic and English in area of Biology, Chemistry, Physics, Mathematics and Computer.

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Contact info

Phone Number:07800709148
E-mail: bsj@csw.uobaghdad.edu.iq
E-mail: baghdadscij@csw.uobaghdad.edu.iq
E-mail:bjs.csw@gmail.com

Table of content: 2009 volume:6 issue:4

Article
Effect of salinity on survival, development and growth of Artemia sp.
تأثير الملوحة على بقاء وتطور ونمو الجنس Artemia1

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Abstract

This study aimed to determine the possibility of culturing genus Artemia in under laboratory conditions for locally culturing and producing. Different salinity concentrations were used, ranging from 5-40g/l . the results showed that the concentration 30g/l is the best for hatching. This concentration recorded hatching efficiency of 68800 nauplii/g cysts and hatching percentage of 45.86%, while the concentration 5g/l recorded less hatching efficiency and hatching percentage of 20266 nauplii/g and 13.5% respectively . Investigating the effect of salinity on individuals survival and growth using saline concentrations ranging from 30to 100g/l, revealed that the best percentage was 75.00% in the first week with 70g/l, whilst the best rates of survival percentage with concentration 80g/l during the second, third and forth week were 58.33,54.61 and 39.58% respectively. The individuals, as a whole, suffered from mortality in the concentration 90 and 100g/l in the forth and third week respectively. The results of salinity effect on growth showed that the best length rate was recorded with the concentration 80g/l for four weeks reaching 9.43mm in the forth week, while the lowest length rate was recorded as 7.03mm in the forth week with concentration 30g/l.


Article
Effect of Different Conditions on Viability and Antagonistic Activity of Saccharomyces boulardii on Enteric Pathogenic Bacteria
تأثير الظروف المختلفة في عيوشية الخلايا والفعالية التثبيطية لخميرة Saccharomyces boulardii ضد البكتريا المعوية المرضية

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In this part of programme , different bacterial isolates mainly Salmonella spp, Shigella spp and Escherichia coli were used for antagonism with Saccharomyces boulardii under different conditions . S.boulardii was grown under aerobic conditions and antagonized with young overnight nutrient broth cultures of test bacterial isolates and other kept in refrigerator for a week after full growth . Young cultures were more susceptible to antagonistic effect of yeast compared to old cultures and on isolates grown on solid medium for 24 hr. S.boulardii grown under aerobic and microaerobic conditions and antagonized with overnight broth cultures of test bacterial isolates , The results revealed that aerobic cultures of yeast had more inhibitory effect on test isolates .Concentration of yeast cells from liquid media GS( prepared from soluble fraction of gluten and mixed with equal volume of corn steep water and GS2%) was found not to be exceeded 109 yeast cell/ ml of suspension due to the large size of yeast cells .Effect of freezing on viability of yeast cells grown in GS and GS2% was negligible and there was no significant differences since the difference was less then half log cycle


Article
Purification and Characterization of protease from Zahdi dates plam seeds (Phoenix dactylifera L.)
تنقية وتوصيف انزيم البروتييز من نوى تمر الزهدي Phoenix dactylifera L.

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Proteinases (E.C.3.4.21) family are widely distributed in the nature; it was present in animals tissues , plants and microbial cell . Protease was purified from Zahdi seed (Phoenix dactylifera L.) by several steps included ammonium sulphite ppt (75%) saturation and dialyzed against the 80mM sodium phosphate buffer at pH 7.5 . The enzyme specific activity was 407.62 unit/mg protein. The obtained extract was purified by DEAE-Cellulose column followed by gel filtration through Sephacyl S-200 column .The enzyme specific activity ,yield and purification fold were 1873.49 unit/mg protein, 22.99 and 58.42% respectively. The results of protease characterization showed that the molecular weight was 25118 daltons as determined by gel filtration. The optimum temperature of the enzyme activity 35 C for 15 minutes and that for stability was 45 C for 15 minutes, using sodium phosphate buffer at pH 7.5, The optimum pH for the enzyme stability and activity were 8.5 for 15 minute and 7.5 respectively.


Article
Urinary tract infection incidence in college students
معدل حدوث التهاب المجاري البولية في طلبة الكليات

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Result of studying (61) urine samples collected from students department of Biology in the College of Education-Tikrit University and the people who hold signs and symptoms of urinary tract infections with those who do not have any signs or symptoms through a questionnaire has been with the collection of samples, and the total cases were infected (39 ) cases, a rate (63.9%) distributed (28) cases a female (68.2%) and male (11) cases event rate (55%), while the distribution of positive cases among age groups have emerged group (20-22 years) is the highest rate (56%) females. The results of urine cultures accompany the presence of different types of bacteria sick and E.coli bacteria is the highest ratios positive also it is the most common causative agents of urinary tract infections ,it is the predominant organism to be isolated. Less frequent causative Staphylococcus aureus . Susceptibility of isolates to various antimicrobial drugs was also studied. The result demonstrates the frequent incidence of resistant bacteria to commonly used drugs especially Ampicilline, Tetracyclin.


Article
Effect of Hardening to drought tolerance on the moisture contents of sunflower plant. II moisture percentage in leaves and heads
تأثير عمليات ألتطويع لتحمل ألجفاف في ألمحتوى ألرطوبي لنبات زهرة ألشمس (Helianthus annuus L.). II .نسبة ألرطوبة في ألأوراق وألأقراص

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Abstract

The objective of this work was to study the changes in the moisture content of the leaves and heads of sunflower plant during growth stages under hardening conditions to drought tolerance . Field experiment was carried out during the spring season of 2000 and 2001. Asplit-split plots design was used with three replications. The main plots included irrigation treatments:irrigation to 100%(full irrigation), 75and50%of available water.The sub plots were the cultivars Euroflor and Flame.The sub-sub plots represented four seed soaking treatments :Control (unsoaked), soaking in water ,Paclobutrazol solution(250ppm),and Pix solution (500ppm). The soaking continued for 24 hours then seeds were dried at room temperature until they regained their original weight. Amount of water for each irrigation were calculated to satisfy water depletion in soil using a neutron meter. Results indicated that moisture content of the leaves was not affected by irrigation treatments .While full irrigation and stress 600 Kp increased moisture content of heads by 1.69 and 2.44%, respectively than stress 800Kp after 58 days from planting in the season 2001.Full irrigation was superior over stress 600 and 800 Kp by 3.66and 1.52% after 72 days from planting as a mean of seasons. Euroflor was superior over Flame in the moisture content of its leaves after86 days from planting by 5.34% in the season of 2001 and by 2.76% as a mean of seasons , and superior in moisture content of its heads by 2.79% in the season of 2001. Soaking in water , paclobutrazol and pix solutions increased moisture content of sunflower leaves by 3.73,2.65 and 4.13% after 58 days from planting as a mean of seasons, and increased moisture content of sunflower heads by 4.05, 5.12 and 5.44% after 58 days from planting in the season 2000 , and by 2.80, 3.09 and 2.86% in the seasons of 2001 compared with unsoaked treatment. In conclusion , soaking the seeds presowing in water or plant growth regulators could improve water relations of the leaves and heads of sunflower plants , which lead to increase flowering, setting and filling of seeds during drought periods.


Article
Biological & Immunological Effect of Ozonated Water on Certain Skin Pathogenic Bacteria In vivo
التأثير الحيوي والمناعي للاوزون المذاب في الماء ضد بعض المسببات المرضية الجلدية البكتيرية داخل الجسم الحي

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Abstract

This in vivo study was conducted to investigate the effect of different concentrations of ozonated water on experimentally skin infection with some of bacterial isolates (Pseudomonas aeruginosa and Staphylococcus aureus ) which Showed dermal infection in experimental animals after 48 hours of exposure to these Microorganisms. Results revealed that ozone has the power to accelerated the healing process depending on the perfect concentration of ozonated water used and the severity of infection & nature of causative agent , in which the recovering period was 7 days for the infection caused by P. aeruginosa and 5 day for S.aureus by using the concentration 60 µg/ml . Results also indicated in this study the stimulated effect of Ozonated water on the immune system For the healthy mice at the concentration 20µg/ml through increasing in Phagocytic index ,Arthus and Delayed Type- Hypersensitivity reaction in addition to the inhibited effect of this material on this immunological Markers when the animals treated with Ozonated water at the concentration 60µg/ml . Different respond appear with the immune system For injured and infected mice when treated with ozonated water depending on the Kind of causing agent and the severity of infection .


Article
Pathological Study of Aspergillus fumigatus in Wild & Laboratory Rabbits in Baghdad City
دراسة مرضية لعفن Aspergillus fumigatus في الأرانب البرية والمختبريةفي مدينة بغداد

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This study was designed to be isolate and identify the fungi Aspergillus fumigatus in wild male rabbits in Baghdad city from (Al Kezel and New Baghdad Markets ) . (50) Male wild rabbits were included in this study , the rabbits were randomly selected kept into animals house in college of vet. medicine in Baghdad University . Eight sample were taken from each wild rabbits for fungal examination included (blood , liver , kidney , spleen , lung, intestine , skin scraping and cotton swabs (from mouth & rectum ) the results revealed that 40% of Aspergillus fumigatus isolated from blood and 20%from skin scraping. In experimental design ,30 white swiss male rabbits were used in this study for (60) days ,they were divided into (3) equal groups 1st group (10) rabbits were 1/P inoculated with common isolated mould in wild rats Aspergillus fumigatus 0.2 ml (1×105 cell/m). 2nd group (10) rabbits were given 0.2 ml 1/P PBs.3rd group (10) rabbits was act as control group. Clinical manifestation of the 1st group characterized by dyspnea , tacchycardia ,alopecia & sudden death with diarrhea . Histopathology observation showed in organs (liver , lung , spleen , intestine ) the presence of hemorrhage , necrosis in spleen and intestine with multifocal areas of granulomatous lesion in liver and lung..


Article
THE EFFECT OF RAMADI SEWAGE TREATMENT PLANT ON THE PHYTOPLANKTON AND SOME PHYSICO – CHEMICAL CHARACTERS IN EUPHRATES RIVER , IRAQ
تأثير محطة معالجة مياه فضلات الرمادي في الهائمات النباتية وبعض الصفاتالفيزيائية والكيميائية لنهر الفرات ، العراق

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Four localities were selected in Euphrates River and Ramadi sewage treatment plant to collect water samples monthly during the period between October 2001 to July 2002 . Total cell count of phytoplankton and its physico- chemical concentrations were determined . The study aimed to demonstrate the effect of Ramadi sewage treatment plant on Euhprates River . It is concluded that the sewage had an dilution effect for the total hardness , total alkalinity , electrical conductivity and salinity of Euphrates River , but it is also caused in the presence of a contaminated area . This was cleared from the depletion of dissolved oxygen and high values of biological oxygen demand with lower valuse of pH in this area . The water of Euphrates River may classified as a hard water with high concentration of Ca and Mg. Bacillariophyceae(Diatoms) was dominated followed by chlorophyceae and cyanophyceae. The other classes were very spare and did not affect the total cell counts .


Article
Effect the combination of antibiotics on clinical isolates of Staphylococcus aureus
تأثير الجمع بين مضادات الحياة على بكتريا Staphylococcus aureus المعزولة سريريأ

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Atotal of 75 different clinical samples were collected from different hospitals in Baghdad Biochemical and morphological characterization tests showed that forty isolates were identified as Staphylococcus aureus Antibiotic susceptibility tests of all isolates towards ten antibiotics were carried out and results showed that many isolates (97.5 %) were resistant to β-lactam antibiotic , 70 % were resistant to Tetracyclinee , 62.5% were resistant to co-trimoxazole , 60 % were resistant to ciprofloxacin , 55% were resistant both of chloramphenicol and erythromycin , 52.5% were resistant to gentamicin , 35% were resistant to rifampicin , 10% were resistant to vancomycin . According to the above results the S.aureus I1 which is isolated from patients with osteomyelitis showed resistant to all ten antibiotics therefore was used in the followed experiments. The minimum inhibitory concentration (MIC) of S.aureus I1 vancomycin, cefotaxim , penicillin G, amoxicillin , ciprofloxacin , co-trimoxazole ,gentamicin, rifampicin was checked.The results showed that isolates had MIC between (390-12500) μg/ml. The combination of different antibiotics with vancomycin showed synergistic effect based on the Fractional inhibitory concentration index (FIC).


Article
Study of properties of electrical conductivity of Tin dioxide thin films treated with Xenon impulse radiation used as Gas sensors
دراسة خواص التوصيلية الكهربائية لأغشية ثاني اوكسيد القصدير الرقيقة المعالجة بواسطة أشعة الزينون النبضية المستخدمة كعناصر تحسس للغازات .

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Abstract

During of Experimental result of this work , we found that the change of electrical conductivity proprieties of tin dioxide with the change of gas concentration at temperatures 260oC and 360oC after treatment by photons rays have similar character after treatment isothermally. We found that intensive short duration impulse annealing during the fractions of a second leads to crystallization of the films and to the high values of its gas sensitivity.


Article
Study of Stability of Personal Dosimeter
دراسة استقرارية افلام قياس مستوى التعرض كسجل دائم للجرع

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Abstract

The study is carried out by using personal dosimeters (film badge). The films are irradiated to absorbed dose of range (0.01-10000 rad). The calibration curves are drawn by using the ordinary method taking into account the filtration effects in three regions (D (Pb/Sn),D(Du),D(300). The calibration films are stored in ambient condition. It is found that the optical density increases, which is attributed to the photodegradation of the films may induce localized states in the energy gap causing increasing in optical absorption, but optical density decreases, which attributed to the photodegradation of the films may cause some cracks at the film surface during the first month, whereas at the rest months we see clear stability in optical density for the irradiated films. Before irradiation, there is increasing in optical density during the second month, and decreasing in optical density during the rest months. It is concluded that aging effects must be considered for personal dosimeter before and after irradiation to know its use ability as a permanent record.


Article
Best estimation for the Reliability of 2-parameter Weibull Distribution
افضل تقدير لمعولية توزيع ويبل ذي المعلمتين

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This Research Tries To Investigate The Problem Of Estimating The Reliability Of Two Parameter Weibull Distribution,By Using Maximum Likelihood Method, And White Method. The Comparison Is done Through Simulation Process Depending On Three Choices Of Models (α=0.8 , ß=0.9) , (α=1.2 , ß=1.5) and (α=2.5 , ß=2). And Sample Size n=10 , 70, 150 We Use the Statistical Criterion Based On the Mean Square Error (MSE) For Comparison Amongst The Methods.


Article
Seasonal Changes of Nutrient Concentrations in Water of Some Locations in Southern Iraqi Marshes, After Restoration.
التغيرات الموسمية لتركيز المغذيات في مياه بعض مناطق اهوار جنوب العراق، بعد اعادة التأهيل

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After restoration of Iraqi marshes during 2003, three locations were chosen, one in each main marsh (Um Al-Naaj site in Al-Hwaizeh marsh; Al-Nagarah site in Al-Hammar marsh and Al-Baghdadia site in Al-Chebaysh marsh) to determine the concentrations of nutrients (Nitrate, Nitrite, Phosphate and Silicate) in water seasonally for the period winter, spring, summer, and autumn at 2007. Five water replicates were collected from each site, seasonally. In the Lab., the samples were analyzed by colorimetric methods; the results showed that Um-Al-Naaj site has the highest nutrients level, while Al-Nagarah site has the lowest level. The statistical program t-test was applied at the significant levels (P-value < 0.01) and (P-value < 0.05) to know the significant differences in the nutrients concentration among the sites, as well as among the seasons. Statistically, the results showed that NO3, NO2, and PO4 concentrations have significant differences among the sites, as well as among the seasons. While, SiO2 concentrations have no significant differences among the sites, but they differed significantly among the seasons.


Article
Antimicrobial activity of grape fruit seed crude extract on microbial growth
الفعالية المضادة للجراثيم لمستخلص بذور نبات الكريب فروت(Citrus paradise) على نمو الجراثيم

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Antimicrobial and antiyeast activity of ethanolic and aqueous extract of grape fruit seed (Citrus paradise ; Rutaceaa) was examined against 10 bacterial and 2 yeast strains. The level of the antimicrobial effects was established using an in vitro agar assay and minimum inhibitory concentration (MIC). In general ethanolic extract were more effective on gram positive bacteria than gram negative bacteria and strongest antimicrobial effect against Streptococcus pyogenes and Salmonella entritidis. Other tested bacteria and yeasts were sensitive to extract ranging from 4 to 16 mg/ml and more.


Article
Determination of glutathione peroxidase (GSH-Pex) activity in sera & RBCs of Iraqi Women With Breast Tumors
تقدير فعالية الكلوتاثايون بيروكسيديز في امصال وكريات الدم الحمراء لنساء عراقيات مصابات باورام الثدي

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Breast tumor patients generally have more oxidative stress than normal females. This was clear from non significant decrease in RBCs and serum of GSH-Pex activity in all groups of patients. The study had found that free radicals in malignant breast tumors were higher than benign tumors; therefore the GSH- Pex might be used as markers for prognosis of the disease.


Article
Study of the Porosity of Certain pharmaceutical Tablets using Mercury Intrusion Porosimeter
دراسة مسامية بعض حبات الدواء بأستخدام مقياس المسامية الزئبقي

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Porosity and pore structure are important characteristics of pharmaceutical tablets, since they influence the physical properties, such as mechanical strength, density and disintegration time. This paper is an attempt to investigate the pore structure of four different paracetamol tablets based on mercury porosimetry. The intrusion volumes of mercury were used to calculate the pore diameter, pore volume and pore size distribution. The result obtained indicate that the variation of the pore volume in the tablets followed the sequence:- S.D.I. Iraq Pharmacare,Dubai-U.A.E. Bron and Burk(UK) LondonLark Laboratories(India), while the variation of surface area followed the sequence:- S.D.I. Iraq Lark Laboratories(India) Pharmacare,Dubai-U.A.E.  Bron and Burk(UK) London


Article
Synthesis of new poly diimides from reaction of poly acryloyl chloride and diamides.
تحضير بولي ثنائي ايمايدات جديدة من تفاعل بولي كلوريد الاكريلويل مع مركبات ثنائي اميد

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Five N-substituted poly diimides were prepared by two steps. First step was included the preparation of five N-substituted diamides by reaction of adipoyl chloride with different amines .The second step was involved reaction of diamides with poly acryloyl chloride to obtain five new poly diimides having different physical properties which may used in different applications.


Article
Synthesis and Characterization of (Fe(II),Co(II),Ni(II) and Cu(II)) Complexes with Schiff Base derived from [benzoyl hydrazine] with [benzyl mono oxime]
تحضير وتشخيص معقدات ثلاثي المنح نوع N2O من تفاعل الليكاندBenzoic acid (2-hydroxy imino – 1,2-di Phyneyl ethylidene) – hydrazide مع ايونات العناصر(Fe (п), Co (п), Ni (п), and Cu (п))

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The reaction of [Benzoyl hydrazine] with [Diphenyl mono oxime] and Glacial acetic acid was carried out in methanol gave a new tridentate ligand [Benzoic acid (2-hydroxyimino- 1, 2-diphyneylethylidene) - hydrazide]. This ligand was reacted with some metal ions (Fe(II), Co(II), Ni(II), and Cu(II)) in methanol with (1:1) metal : ligand ratio to give a series of new complexes of the general formula [M(L)Cl2.H2O], where M= Fe(11), Co(11), Ni(11) and Cu(11). All compounds were characterized by spectroscopic methods (I.R, UV-Vis), elemental microanalysis (C.H.N), atomic absorption, magnetic susceptibility, and conductivity measurements. From the obtained data the proposed molecular structures were suggested for the complexes of Fe (II), Co (II), Ni (II) and Cu (II) are of geometric octahedral.


Article
Study of Molecular Interactions of Water- Soluble Polymer at Several Temperatures in Solution
دراسة التآثرات الجزيئية لبوليمر ذو قابلية الذوبان في الماء على مدى عدة درجات حرارية في المحلول

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Molecular interactions between 2-isopropenylnaphthalene-methacrylic acid (IPNMA) block copolymer( as a model for water- soluble polymer) and methanol at several temperatures were studied using fluorescence techniques , Fluorescence spectrum for (IPNMA) exhibits two emission bands at around 342 nm and 387 nm corresponding to the monomer and the excimer bands , respectively .The fluorescence spectra of dilute solution of (IPNMA) in methanol were recorded in temperature range of 8- 45˚C . Plot of the excimer to monomer intensity ratio Ie/Im versus temperature was obtained, which shows double lines with positive slopes crossing at 25˚C , the increasing of slope value above this temperature is small which indicates that there is stronger solvation of methanol molecules to polymer coil at temperature below 25˚ C arising from hydrogen bond formation between the polymer and the solvent .


Article
Carbonization and Treatment the High Temperature Distortion of Thoriated Tungsten Cathode for High Power Electronic Tubes
كربنة ومعالجة تشوه كاثود التنكستن المطعم بالثوريا عند درجات الحرارة العالية للصمامات الالكترونية العالية القدرة

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A metal mandrel was designed for manufacturing the cathodes of high power electron tube ( Tetrode ) used in broadcasting transmitting tubes type TH558 and CQS200.The cathodes were manufactured in the present work from thoriated tungsten wires ( 2٪ ThO2- W) with different diameters .These cathodes were carbonized in sequences of processes to determine the carbonization parameters (temperature, pressure, time, current and voltage).Then the carbonized cathodes dimension were accurately measured to determine the deviation due to the high temperature distortion effect at about 1800°C .the distorted cathodes due to the carbonization process was treated when it was subjected inside the vacuum chamber and heat treated again .The carbonized cathode distortions as a function of temperature were measured in the range of (1500°C-1800°C).The temperature was determined using an optical pyrometer and also calculated using Stephan's-Boltzmann relation.


Article
Titania Effect on Sintering behavior of Alumina
التأثير التيتاني على سلوكية تلبيد الألومينا

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The sintering behavior of Alumina was investigated by adding TiO2. The addition of TiO2 lowered the sintering temperature of the Alumina compared with those of pure Alumina. The result suggests that TiO2 acts as an activator for sintering of Alumina. Water absorption, apparent porosity and density were examined for both pure and TiO2 added to Alumina samples. The variations of sintering behavior were discussed in terms of shrinkage, porosity, water absorption and density. Thermal shock resistance was also examined. In term of this work, the way of improving the thermal shock resistance in oxide- based materials by adding reactive Titania powder to the Alumina samples. The laboratory results showed an improvement in thermal shock resistance property of the products which open the horizon of development of the final products.


Article
Preparation of Electrical Conducting Polymer CompositesFrom Polyvinylchloride (PVC) Resin and StudyingSome its Electrical Properties
تحضير متراكبات بوليمرية من راتنج البولي كلوريد الفانييل (PVC)موصلة كهربائياً ودراسة بعض خصائصها الكهربائية

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The D.C electrical and thermoelectrically properties of randomly mixed isolator – electrolyte system as (Al/ PVC – LiF/Al) junction consisting of polyvinyl chloride (PVC)resin reinforced with Lithium Fluoride (LiF) powder were studied. A comparison is made the properties of (PVC) material with varying percentage of (LiF) powder (0%, 30%, 50%, 80%)to find out the effect of reinforcement of isolator material. The composites dissolving in 10ml form tettraHaedroflourn (THF) and Solution were the castled in Petri dish and Laved it dry in the air, The out coming Sample were disc - Like shape of a diameter of about 3cm and thickness reneged between (0.01- 0.018) cm . The composites dissolving in 10ml form tettraHaedroflourn (THF) and Solution were the castled in Petri dish and Laved it dry in the air, The out coming Sample were disc - Like shape of a diameter of about 3cm and thickness reneged between (0.01- 0.018) cm . The experimental results show that current and the conductivity of (PVC - LiF) composites increase by three orders of magnitude when the volume fraction (LiF Vol.%) increase and so dose with temperature. The activation energy of the thermal rate - process of the electrical conductivity is determined and found to decrease with increasing the LiF vol. % content. We find that this composite has good conductivity, light weight and easily manufactured. These very good ideal characteristics can make the composite very suitable to be used commercially


Article
Mean-field Solution of the mixed spin-1 and spin-5/2Ising system with different single-ion anisotropies
دراسة الحالة الطورية لنظام فيري مغناطيسي خليط من نوعين من المواد باستخدام نموذج أيزنك

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The mixed-spin ferrimagnetic Ising system consists of two-dimensional sublattices A and B with spin values and respectively .By used the mean-field approximation MFA of Ising model to find magnetism( ).In order to determined the best stabile magnetism , Gibbs free energy employ a variational method based on the Bogoliubov inequality .The ground-state (Phase diagram) structure of our system can easily be determined at , we find six phases with different spins values depend on the effect of a single-ion anisotropies .these lead to determined the second , first orders transition ,and the tricritical points as well as the compensation phenomenon .


Article
The influence of He-Ne Laser (632.8 nm) on Candida albicans isolated from complete upper dentures: In vitro study
تأثير ليزر الهليوم نيون بالطول الموجي (632.8) على خميرة المبيضات المعزولة من طقم الأسنان العلوي الكامل: دراسة مختبرية في الزجاج

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The main objective of this study is to determine whether the use of He-Ne Laser (632.8 nm wavelength and power 0.5 mW) is an eligible and effective tool to kill or reduce the cell viability of Candida albicans isolated from complete upper dentures. Twenty one swabs were taken from the complete upper dentures. Only six swabs showed positive cultures for C. albicans. The isolate was divided into two groups, group I was not irradiated (control), and group II was irradiated by He-Ne Laser for different periods (10, 15, 20, and 30) min. After irradiation, the results showed a significant reduction in the viable cell count and colonies diameters especially at exposure periods 10 and 15 min. Although the low power He-Ne Laser was not eradicating the cell itself, but it affected on the viable cell count and colonies diameters comparing with the control.


Article
Study the effect of position on the time of astronomical twilight
دراسة تأثير ارتفاع الموقع على مدة الشفق الفلكي

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Twilight is that light appear on the horizon before sunrise and after sunset, Astronomically it is known that sunrise and sunset are effected by high above sea level, but the effect of high above sea level on the time of astronomical twilight still not decided and controversy among astronomers, in This research we studies the effect of high above sea level on the time of astronomical twilight, through adding the equation correct high above sea level to equation computation of twilight and then calculate of changing in the time of twilight for different highest (0-10000) meters above sea level , and the ratio of increase for time with high between (15.45-20.5) minutes. It was found that there was an increase in the time of the twilight along the year when increasing high above sea level and that surely effected time of astronomical twilight with high above sea level, but this effect is strong for high to 2000 meters and then high effect will be less to increasing the time of twilight.


Article
Speaker Authentication Using Vector Quantization
التحقق من هوية المتكلم باستخدام التكميم الاتجاهي

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In this paper, the role of the vector quantization in the speaker authentication system was studied. Vector quantization based speaker authentication system was considered in two phases; training and testing. The training phase concerned with enrolling the speaker models to build the codebook. The codebook generated from a set of feature vectors belong to each sample of speaker's voice. The testing phase includes matching the unknown input speaker with the models. The matching is performed by evaluating the similarity measure between the unknown speech sample and the models in the speaker database to authenticate the input speaker. A weighted similarity measure was introduced; it takes into regard the correlations between the known models in the database. Larger weights are assigned to vectors that have high discriminating power between the speakers and vice versa. The proposed system gave an encourage results; the authentication rate was about 86.6% during a time 4 s.


Article
Decoding Reed- Muller Codes by Using Hadamard Matrices
كشف شفرات ريد-مولر(Reed-Mulle) باستخدام مصفوفات هادمارد(Hadamard)

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Abstract

This paper discusses the problem of decoding codeword in Reed- Muller Codes. We will use the Hadamard matrices as a method to decode codeword in Reed- Muller codes.In addition Reed- Muller Codes are defined and encoding matrices are discussed. Finally, a method of decoding is explained and an example is given to clarify this method, as well as, this method is compared with the classical method which is called Hamming distance.


Article
Some Results of Feebly Open and Feebly Closed Mappings
بعض النتائج حول التطبيقات الضئيلة المفتوحة و الضئيلة المغلقة

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Abstract

The main purpose of this paper is to study feebly open and feebly closed mappings and we proved several results about that by using some concepts of topological feebly open and feebly closed sets , semi open (- closed ) set , gs-(sg-) closed set and composition of mappings.


Article
Automatic Block Selection for Synthesizing Texture Images using Genetic Algorithms
اختيار القطع بشكل آلي في تركيب الصور النسيجية باستخدام الخوارزميات الجينية

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Abstract

Texture synthesis using genetic algorithms is one way; proposed in the previous research, to synthesis texture in a fast and easy way. In genetic texture synthesis algorithms ,the chromosome consist of random blocks selected manually by the user .However ,this method of selection is highly dependent on the experience of user .Hence, wrong selection of blocks will greatly affect the synthesized texture result. In this paper a new method is suggested for selecting the blocks automatically without the participation of user .The results show that this method of selection eliminates some blending caused from the previous manual method of selection.

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