research centers


Search results: Found 13

Listing 1 - 10 of 13 << page
of 2
>>
Sort by

Article
22- RESIDUAL DISTRIBUTION OF LEAD, CHROMIUM AND COBALT IN DAIRY PRODUCTS AND THEIR BY-PRODUCTS MANUFACTURED FROM MILK SPIKED WITH THESE METALS

Author: Hiba S. Al-Naemi
Journal: Basrah Journal of Veterinary Research. مجلة البصرة للابحاث البيطرية ISSN: Print:18138497 E; 24108456 Year: 2018 Volume: 17 Issue: 1 Pages: 257-276
Publisher: Basrah University جامعة البصرة

Loading...
Loading...
Abstract

The research study the distribution patterns and residues behavior of Pb, Cr and Cobetween dairy products [yoghurt, cheese and fatty dairy products ( kishfa, Gaymer andcream)] and their by-products (whey and skim milk) manufactured fromexperimentally polluted raw ewe̓ s, buffalo̓ s and cow̓ s milk were investigated usingAtomic Absorption Spectrophotometer (AAS). The studied metals (Pb, Cr and Co)were concentrated in both cheese and fatty dairy products (kishfa, gaymer and cream)as they recorded concentration factors in cheese produced from raw ewe̓ s, buffalo̓ sand cow̓ s milk of 3.849, 3.466 and 2.452, 3.804, 2.938 and 2.342 and 2.995, 2.682and 2.336 folds, respectively and 3.693, 3.164 and 2.339, 3.347, 2.773 and 2.242 and2.601, 2.156 and 2.14 folds, respectively in kishfa, gaymer and cream produced fromraw ewe̓ s, buffalo̓ s and cow̓ s milk compared with metals concentrations reported inraw milk used for preparing these products, whereas the by-products of cheese andfatty dairy products processing (whey and skim milk, respectively) contained Pb, Crand Co concentrations lower than these present in raw milk as they recorded reductionlevels of 71.6, 58 and 31.7, 63.7, 39.5 and 27 and 31.4, 20 and 9.5%, respectively inwhey and 37.3, 29.9 and 12.1, 41.7, 27 and 19.3 and 21.3, 7.8 and 5.2%, respectivelyin skim milk. Yoghurt processed from the raw ewe̓ s, buffalo̓ s and cow̓ s milkcontained Pb, Cr and Co metals at mean concentration levels similar to and slightlyless than those found in raw milk as the reduction levels amounted 0, 0.6 and 1, 0.1,0.7 and 1.4 and 0.6, 0.8 and 1.9%, respectively. Generally, metals exhibited significantdifferences (p˂0.05) in their distribution and residues behavior in dairy products andtheir by-products and comparable to raw milk used in processing as they arranged as follows: cheese> fatty dairy products (kishfa, Gaymer and cream)> raw milk>yoghurt> skim milk> whey, except yoghurt and raw milk which difference was notsignificant (p˂0.05). Also, metals found in studying dairy products in the order of Pb >Cr > Co, in contrast to their by-products as they arranged reversibly. Finally, metalsconcentrated in cheese and kishfa produced from raw ewe̓ s milk, in addition to cheeseand gaymer produced from raw buffalo̓ s milk at levels significantly higher (p˂0.05)than those present in cheese and cream produced from raw cow̓ s milk.

Keywords

Lead --- Chromium --- Cobalt --- Dairy products.


Article
Environmental Risk Assessment of Industrial Soil Polluted with Chromium

Authors: Rawnaq S. Mahdi --- Athmar A. Al-Mashhady
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 1 Part (C) Pages: 49-53
Publisher: University of Technology الجامعة التكنولوجية

Loading...
Loading...
Abstract

Thirty-five soil samples were collected from the Tanning FactoryIndustrial District within Baghdad city to investigate the soil pollution occurthrough four directions of the tanning plant. The soil samples exhibited highconcentrations of Cr than the reported values of worldwide mean of unpollutedsoils. The geoaccumulation index showed that the soil samples were moderatelypolluted by Cr at the north of the factory while the soil sample showed extremelypolluted at the south and east of the factory. Moreover, the soil samplescollected from west of the factory were strongly polluted. The result of thecalculated enrichment factor (64.52-1075.22) showed to extremely highenriched and suggesting a significant role of anthropogenic pollution because ofvarious industrial activities by the Tanning Factory


Article
Fabrication and Characterization of Chromium Nanotube Using (AAO) Template

Authors: Rana Afif Anaee --- Ahmed Rajih Hassan
Journal: Journal of University of Babylon مجلة جامعة بابل ISSN: 19920652 23128135 Year: 2018 Volume: 26 Issue: 2 Pages: 152-159
Publisher: Babylon University جامعة بابل

Loading...
Loading...
Abstract

In the current research, the fabricating of Cr nanotubes was done by electrochemical deposition in anodic aluminum oxide (AAO) as template. Characterization of fabricated Cr nanotubes were a achieved by XRD, SEM/EDS and TEM. These techniques indicated that the deposited chromium nanotubes have high purity within experimental conditions, the peaks in XRD was good agreement with JCPDS cards, SEM images showed the growth of ordered nanotubes in one plane perpendicular to the template (AAO). The purity of fabricating nanotubes was confirmed by EDS analysis, while the produced single walled nanotubes was shown from TEM images with open ends of tubes. 60 nm as diameter was obtained for fabricating Cr nanotubes.The fabrication of Cr nanotubes suggests producing quintuple bonds (Cr ≡ Cr) to form tubes without any chance to deposit chromium as particles.

في البحث الحالي تم تصنيع Cr Nanotube بعملية الترسيب الكهروكيميائي وذلك بترسيبها على أساس من الألمنيوم المؤنود AAO كذلك تم تشخيص الأنابيب الكروم النانوية بواسطة XRD, SEM/EDS and TEM . وقد تبين من خلال هذه التقنيات إن الأنابيب الكروم النانوية كانت تمتلك نقاوة عالية جدا , ومن خلال تقنية SEM لوحظ نمو منتظم للأنابيب النانوية على مستوى عمودي للـ AAO. وكذلك يتضح ذلك من خلال تقنية TEM والتي يظهر فيها الأنابيب ذات جدار منفرد single wall بقطر مقارب إلى 60nm.


Article
CONSTRUCTION OF SLURRY JET EROSION TESTER AND THE EFFECT OF PARTICLE SIZE ON SLURRY EROSION

Authors: Israa F. Yousif --- Ali H. Ataiwi
Journal: KUFA JOURNAL OF ENGINEERING مجلة الكوفة الهندسية ISSN: 25230018 Year: 2018 Volume: 9 Issue: 3 Pages: 17-25
Publisher: University of Kufa جامعة الكوفة

Loading...
Loading...
Abstract

A Jet erosion tester is designed and used to study the relative erosion behavior of high chromium white cast iron (ASTM 532A) at specific concentration of silica sand as an abrasive material, 45° impact angle and two size of abrasive particles. A slurry pot was used which contains two propellers rotated at the speed required for uniform distribution. The test specimens are mounted on test fixture which is fixed and has a provision to move in different angular position to find out the wear for different angles. Two different experiments are conducted preliminarily by using silica sand as abrasive with particle size of 400-600 µm and 600-800 µm. Impact angle of 45° and solid abrasives of 20% wt. concentration are used as fixed parameters for 10 hours. It was found that the erosion resistance decreases with increasing the abrasive particle size.


Article
Evaluation of antioxidants and reactive oxygen species (ROS) levels after combination exposure to chromium (III) and atrazine on liver in Wister Albion male rats

Author: Sabah H. Enayah
Journal: Iraqi Journal of Biotechnology المجلة العراقية للتقانات الحياتية ISSN: 18154794 Year: 2018 Volume: 17 Issue: 1 Pages: 67-77
Publisher: Baghdad University جامعة بغداد

Loading...
Loading...
Abstract

Atrazine (ATZ)is remaining as one of the most widely broad spectrum pesticide used to control on annual grasses and broadleaf weeds. While Chromium Cr (III) it has been used currently as food supplemented. The current study was designed to determine impact of Cr at 7,30 and 300ppm on liver was in absence or in the present of (25 and 50mg/kg) of ATZ for 6 weeks in rats. Results indicated that deficiency or supplementation with Cr did not cause measurable toxicity and has no obvious effect on oxidative stress or anti-oxidant enzymes and lipid metabolism. Furthermore, the results showed that the mixture increased level of Aryl Hydrocarbon Receptor (AhR), Reactive Oxygen Species (ROS). Moreover, the mixture had effects on antioxidants such as super oxide dismutase (SOD), Catalase (CAT), Reduced glutathione (GSH), activity where demonstrated more sever in liver tissue compared to Cr alone, especially as dose of ATZ increased. Moreover, as dose of Cr in the mixture was increased, the ROS, AhR, CAT, GSH activity was increased compared to low Cr values. However, SOD activity showed reduction in elevation of mixture concentrations. The results of this study suggest that there is synergic impact of co-exposure to ATZ and Cr on the parameters used as markers for liver toxicity in the current study. Further studies are warranted to investigate the interact of Cr and ATZ toxicity in more detail and to avoid having the Cr supplement where ATZ exposure is identified.


Article
Adsorption study of some inorganic elements on the surface of activated charcoal prepared from ceratonia siliqua
دراسة امتزاز بعض العناصر اللاعضوية على سطح الفحم المنشط المحضر من الخرنوب

Authors: Sarhan A Salman سرحان علي سلمان --- , Faiz M Hameed فائز محسن حامد --- , Wesam F Ahmed وسام فارس احمد
Journal: Tikrit Journal of Pure Science مجلة تكريت للعلوم الصرفة ISSN: 18131662 Year: 2018 Volume: 23 Issue: 9 Pages: 61-66
Publisher: Tikrit University جامعة تكريت

Loading...
Loading...
Abstract

This study included the process of adsorption of some inorganic elements known as environmental risk (Cd, Cr, Cb, Pb) of its water solutions on the surface of activated charcool to ceratonia siliqua . The percentage of adsorption and isothermal adsorption curves were calculated according to equation, as well as the effect of temperature , pH and particle size of adsorbent on the adsorption of these elements. The study included the comparative study of the adsorption with natural ceratonia siliqua powder. The results showed an optimum conditions at PH=5 and the partical size of adsorbent was 500 μm, while the percentage of adsorption ranged from 81% to 93% .

تضمنت الدراسة عملية االامتزاز لبعض العناصر اللاعضوية المعروفة بخطرها البيئي (Cd،Cr،Cb ،Pb) من محاليلها المائية على سطح الفحم المنشط للخرنوب، والنسبة المئوية للامتزاز الايزوثيرمي. وكذلك تاثير درجة الحرارة والأس الهيدروجيني وحجم الدقائق على امتزاز العناصر، وكذلك دراسة مقارنة للأمتزاز باستخدام مسحوق الخرنوب الطبيعي وبينت النتائج الظروف المثلى باستخدام pH=5 وحجم الدقائق للمادة المازة كان 500 μm, وان النسبة المئوية للأمتزاز كانت 81% الى 93%

Keywords

ceratonia siliqua --- adsorption --- cadmium --- chromium --- copper --- lead --- balance


Article
EFFECT THE COATED LAYER OF HARD CHROMIUM ON FATIGUE BEHAVIOR FOR AISI 1039 MEDIUM CARBON STEEL

Authors: Zeyad Dushan Kadhim --- Mohammed Abdulraoof Abdulrazzaq --- Zahraa Naseef Jassim
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2018 Volume: 22 Issue: 2 (Part-3) Pages: 72-85
Publisher: Al-Mustansyriah University الجامعة المستنصرية

Loading...
Loading...
Abstract

In this paper, study the effect of fatigue behavior on AISI 1039 medium carbon steel electroplated with hard chromium in which the electro deposition method was carried out within a period of 10, 15, 20, 25, 30 minutes plating time, As shot peening were used in this work as a type of surface treatment in which peening was carried out with steel balls for a period of 10 minutes. It was found that the highest fatigue limit was 300 MPa in case of 10 minutes chromium plated shot peened steel , also it was observed there is reduction in fatigue limit with increasing in time of electroplating. Coating thickness increases as coating time increasing and this leading to lower the fatigue limit, where the highest coating thickness value was 33µm with 30 minutes coating time and fatigue limit is reduced till 250 MPa. Also it was found that the coating thickness causes an increase in surface hardness of the alloy. While as coating thickness increased the surface roughness decreased.


Article
Effect of Process Variables, Adsorption Kinetics and Equilibrium Studies of Hexavalent Chromium Removal from Aqueous Solution by Date Seeds and its Activated Carbon by ZnCl2

Author: Samar K. Theydan
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2018 Volume: 19 Issue: 1 Pages: 1-12
Publisher: Baghdad University جامعة بغداد

Loading...
Loading...
Abstract

The adsorption of hexavalent chromium by preparing activated carbon from date seeds with zinc chloride as chemical activator and granular date seeds was studied in a batch system. The characteristics of date seeds and prepared activated carbon (ZAC) were determined and found to have a surface area 500.01 m2/g and 1050.01 m2/g , respectively and iodine number of 485.78 mg/g and 1012.91 mg/g, respectively. The effects of PH value (2-12), initial sorbate concentration(50-450mg/L), adsorbent weight (0.004-0.036g) and contact time (30-150 min) on the adsorption process were studied . For Cr(VI) adsorption on ZAC, at 120 min time contact, pH solution 2 and 0.02 adsorbent weight will achieve an amount of 35.6 mg/g adsorbed . While when use date seeds as adsorbent , conditions of 3 solution pH, 0.02 absorbent weight , and 120 contact time gave 26.49 mg/g adsorbed amount. Using both Langmuir, Freundlich and Sips models were explain the dsorption isotherms. It declare that the Sips model fits well with the experimental data with a maximum Cr( VI) adsorption capacity for (ZAC) and granular date stone 233.493 and 208.055 mg/g, respectively . The kinetics data which obtained at different initial Cr(VI) concentrations were examined by using pseudo-first-order, pseudo-second-order, and intra-particle diffusion models . The result gained showed that the second-order model was only describing well the empirical kinetics data of both (ZAC) and granular date seeds. It was noticed that the granular date seeds has adsorption performance lower than the (ZAC).

يهدف البحث إلى ازالة ايون الكروميوم باستخدام نوى التمر المطحون و الكاربون المنشط المحضر من نوى التمر بطريقه التنشيط الكيميائي وباستعمال كلوريد الزنك كعامل منشط. ايضا بينت النتائج الكاربون المنشط الناتج باستخدام كلوريد الزنك كعامل منشط كان ذو مسحه سطحيه (1050,01 متر2 /غرام) ونسبه امتزاز لليود ( 1012,91 ملغرام / غرام). بينما تم تحديد المساحة السطحية و نسبة امتزاز اليود500,03 متر2 /غرام و485,78 ملغرام / غرام . تم دراسة تأثير قيمة pH (2-12) , التركيز الاولي ل ايون الكروميوم (50 -450) ملغرام/ لتر , وكمية المادة المازة (0,004-0,036غرام ) و زمن امتزاز (30-150 دقيقة) . تم الحصول سعه امتزاز لأيون الكروميوم عند استخدام الكاربون المنشط بالزنك كلورايد (35,6 ملغم/غرام) عند الظروف التشغيليه : pH(2), وزن المادة المازه الى( 0,02غرام) , وزمن امتزاز (120 دقيقه). في حين عند استخدام نوى التمر كمادة مازة , تم الحصول على سعه امتزاز (26,49 ملغم/غرام) عند الظروف التشغيليه : pH (3 ), وزن ماده مازه (0,02 غرتم) , وزمن امتزاز ( 120دقيقه). تم استخدام معادله سيبس بشكل ناجح لتمثيل نتائج امتزاز ايون الكروميوم على الكاربون المحضر ونوى التمر , حيث اعطى اعلى سعه امتزاز لايون الكروميوم على الكاربون المحضر ونوى التمر (233,493ملغم/غرام) و (208,055 ملغم/غرام) على التوالي.ايضا تم دراسة حركية عملية الامتزاز و بينت النتائج ان معادلة الدرجة الثانية مثلت النتائج التجريبية لعملية الامتزاز بشكل جيد ل ايون الكروميوم على الكربون المحضر ونوى التمر .


Article
DESTABILIZATION HEAT TREATMENT EFFECT ON EROSIVE WEAR CHARACTERISTICS OF HIGH CHROMIUM WHITE CAST IRON

Authors: Ali H. Ataiwi --- Israa F. Yousif
Journal: KUFA JOURNAL OF ENGINEERING مجلة الكوفة الهندسية ISSN: 25230018 Year: 2018 Volume: 9 Issue: 2 Pages: 45-56
Publisher: University of Kufa جامعة الكوفة

Loading...
Loading...
Abstract

In the present investigation, erosive wear property of high chromium white cast irons (HCWI) is reported. HCWI were destabilized at two different temperatures of 955oC and 1100°C, air cooling followed by tempering heat treatment at 400°C and 700°C at each destabilized temperature. Erosion damage was evaluated by the removed material mass at impact angle 45° and time of 10 Hours. The surface metal flow was observed. Surface morphology of each specimen was characterized with scanning electron microscopy (SEM). The effect of heat treatment on differences in wear features of specimens is discussed. Experiment showed that the erosion rate of specimen destabilized at 1100°C, air cooled followed by tempering at 400°C air cooling is the best than other treatments. The hardness of test surface by this treatment increased from the initial 57 to 58 HRC after 10 hour. It showed that austenite in the surface structure has been transformed to martensite , which hardened the surface. Similarly, work- hardening effect also occurred on specimen destabilized at 955°C, air cooled followed by tempering at 400oC, air cooling to make its surface hardness increased to 59 HRC. It was shown that HCWI series heat treated at 955°C and 1100°C and tempered at 400°C have a very good erosive wear resistance and they are expected to find wide application as wear-resistant materials.


Article
Effect of Laser Surface Melting on Chromium Carbide of 304 Stainless Steels

Authors: Sami I. Jafar --- Mohammad J. Kadhim --- Sameer K. Faayadh
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 3 Part (A) Engineering Pages: 344-349
Publisher: University of Technology الجامعة التكنولوجية

Loading...
Loading...
Abstract

In the present study, the effects of laser surface melting (LSM) on chromium carbide of heat treated (AISI 304) austenitic stainless steels (ASS) was studied with the aim to suppress sensitization of 304SS. Austenitic stainless steels were heated (aging) up to (800) ºC at constant holding time for two hours. LSM was conducted by using a (600 W) Yb-YAG laser. The microstructure was characterized by using optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Results shows, refined and homogeneous microstructure which contains austenite (γ) as basically phase and delta ferrite (δ) as the secondary phase, however, chromium carbide (Cr23C6) phase are fully dissolved. Desensitization of heat treated ASS has been successfully achieved by LSM which reduced Cr depletion at the grain boundaries.

Listing 1 - 10 of 13 << page
of 2
>>
Sort by
Narrow your search

Resource type

article (13)


Language

English (12)


Year
From To Submit

2018 (13)