73 research outputs found

    Numerical Investigation of Heat Transfer Enhancement in a Circular Tube with Rectangular Opened Rings

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    Turbulent forced convection of coolant air flow (10 m/s velocity) in a steel tube of 50 cm long having outside diameter of 60 mm and inside diameter of 30 mm with constant outside surface temperature of 1000, 1200 and 1400 Ko is numerically analyzed. The renormalization group k-Īµ model is used to simulate turbulence in ANSYS - FLUENT 14.5. An opened ring of rectangular cross section (5x7 mm) is fitted in the tube and separated by 8cm pitch. Results of temperature and velocity distribution along the tube center line for the case of tube with internal ribsĀ  were compared with that of plain tubeĀ  , these results show that the use of internal ribs enhance the heat transfer rate and found to possess the highest performance factors for turbulent flow

    NUMERICAL INVESTIGATION OF HEAT TRANSFER ENHANCEMENT IN A CIRCULAR TUBE USING RIBS OF SEPARATED PORTS ASSEMBLY

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    The paper deals with numerical investigation for the influence of separated ports assembly ribs on heat transfer ina steel tube of 50 cm long , outside diameter of 60 mm and inside diameter of 30 mm with constant outside surface temperature of 1000, 1200 and 1400 Ko.The renormalization group k-Īµ model is used to simulate turbulence in ANSYS - FLUENT 14.5. The ribs assembly (5x5 mm triangle passage) were fitted in the tube and separated by 8cm pitch. Results of temperature and velocity distribution along the tube center line for the case of tube with internal ribs were compared with that of plain tube , these results show that the use of internal ribs enhance the heat transfer rate and found to possess the highest performance factors for turbulent flow

    Preparation of (Pomegranate Peel- Polystyrene) Composites and Study their Optical Properties

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    In this work, samples of pure polystyrene and polystyrene (PS) doped with (pomegranate peel)Ā  were prepared using casting method .The effect of addition of pomegranate peel (PP) concentration on optical properties of poly styrene have been studied in the wavelength range (200-800)nm. The absorption coefficient, energy gap, refractive index and extinction coefficient have been determined. The results show that the optical constants change with increase of PP concentration. Key words: polymer , Polystyrene, pomegranate peel, Optical properties, absorbance

    Optical Properties of (PVA-CoCl2) Composites

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    Polymers are used in a wide range of manufacture applications for their low cost, light weight, mechanical and optical properties. In this paper, study effect of addition cobalt chloride onĀ  opticalĀ  properties of poly-vinyl alcohol(PVA). The cobalt chloride was add to poly-vinyl alcohol with weight percentages are (0,1,2,4) wt.%. The absorption and transmissionĀ  spectra has been recorded in the wavelength range (200-800) nm. The experimental results showed that the absorption coefficient, optical energy gap, extinction coefficient, refractive index andĀ  real and imaginary dielectric constant effected by addition different weight percentages from cobalt chloride. Keyword: polymer, optical constants, absorption, cobalt chloride

    Employing Neural Style Transfer for Generating Deep Dream Images

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    In recent years, deep dream and neural style transfer emerged as hot topics in deep learning. Hence, mixing those two techniques support the art and enhance the images that simulate hallucinations among psychiatric patients and drug addicts. In this study, our model combines deep dream and neural style transfer (NST) to produce a new image that combines the two technologies. VGG-19 and Inception v3 pre-trained networks are used for NST and deep dream, respectively. Gram matrix is a vital process for style transfer. The loss is minimized in style transfer while maximized in a deep dream using gradient descent for the first case and gradient ascent for the second. We found that different image produces different loss values depending on the degree of clarity of that images. Distorted images have higher loss values in NST and lower loss values with deep dreams. The opposite happened for the clear images that did not contain mixed lines, circles, colors, or other shapes

    Effects of Metformin and diet on hemoglobin, cholesterol and triglyceride levels of Type 2 diabetic Patients

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    Metformin is recommend as the first line oral agent to be used patients with non-insulin-dependent diabetes mellitus(Type 2 Diabetic).The study was prospectively performed in diabetic and endocrine center of Nassiriyah city .The present study aimed to shed light on metforminĀ  andĀ  hemoglobin(Hb) and lipid profile in type II diabetic patients with diet and without diet . Our study included 60Ā  patients treated with metforminĀ  for Twelve-week . The subjects were divided into three groups. Group I as control, group IIĀ  patients received Metformin- (1000/2 mg/day) with diet andĀ  group IIIĀ  patients received the Metformin-(1000/2 mg/day) without dietĀ  all these patient had been selected from those patients visit . The Hb concentration and lipid profile were been examine after 3 months of treatment.In present study we found the hemoglobin concentration reduced in group II with diet patient compare with the group III and control group also reduced in the group III without diet patient compare with control group, as same time This study showed that the treatment with metformineĀ  led to, reductions observed in the cholesterol concentrations of the group II diabetic patients with diet compared with the group III administered MET respective withoutĀ  dietĀ  diabetic and compared with control, Also we found the triglyceride concentrations of diabetic patients in group administered MET respective with diet were significantly (p<0.05) reduced compared with that of without dietĀ  diabetic andĀ  control therefore it was considered predisposing factor to reduced damage diabetes. For this reason; continuous taking of metaformin should be important in medicine and general healthy, and they must be not used unless consult of specialists.

    Wounding rapidly alters transcription factor expression, hormonal signaling, and phenolic compound metabolism in harvested sugarbeet roots

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    Injuries sustained by sugarbeet (Beta vulgaris L.) roots during harvest and postharvest operations seriously reduce the yield of white sugar produced from stored roots. Although wound healing is critically important to reduce losses, knowledge of these processes is limited for this crop as well as for roots in other species. To better understand the metabolic signals and changes that occur in wounded roots, dynamic changes in gene expression were determined by RNA sequencing and the activity of products from key genes identified in this analysis were determined in the 0.25 to 24Ā h following injury. Nearly five thousand differentially expressed genes that contribute to a wide range of cellular and molecular functions were identified in wounded roots. Highly upregulated genes included transcription factor genes, as well as genes involved in ethylene and jasmonic acid (JA) biosynthesis and signaling and phenolic compound biosynthesis and polymerization. Enzyme activities for key genes in ethylene and phenolic compound biosynthesis and polymerization also increased due to wounding. Results indicate that wounding causes a major reallocation of metabolism in sugarbeet taproots. Although both ethylene and JA are likely involved in triggering wound responses, the greater and more sustained upregulation of ethylene biosynthesis and signaling genes relative to those of JA, suggest a preeminence of ethylene signaling in wounded sugarbeet roots. Changes in gene expression and enzymes involved in phenolic compound metabolism additionally indicate that barriers synthesized to seal off wounds, such as suberin or lignin, are initiated within the first 24Ā h after injury

    Constructing public health policies in post crisis countries: lessons to learn from the associations between free-sugars consumption and diabetes, obesity and dental caries before, during and after sanctions in Iraq.

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    BACKGROUND: This article aims to provide evidence for an informed public health policy on free-sugar consumption in post-crisis countries. METHODS: Iraq was selected as a case study. A systematic search for published data on the prevalence/incidence of type-2 diabetes, overweight/obesity, dental caries and free-sugar consumption levels in Iraq was conducted using MEDLINE, the Iraqi Academic Scientific journals and relevant international organisations' websites. Comparable data before (1980-1990), during (1991-2002) and after (2003-2015) the United Nations sanctions (UNS) were included. RESULTS: Ten studies were included. Quality scores ranged between 3 and 7/8. Free-sugar consumption decreased dramatically during the UNS (from 50 to 16.3Ā kg/person/year) and started increasing afterwards (24.1Ā kg/person/year). Changes in type-2 diabetes, overweight/obesity and caries levels mirrored those of free-sugar consumption. Caries declined markedly during UNS and started increasing afterwards. Comparable data on diabetes and overweight/obesity were only available for the periods during and after the UNS. Both of these conditions started increasing with increased free-sugar consumption after lifting the UNS. CONCLUSIONS: There is a need to develop a public health policy in post-crisis countries to maintain the reduction in free-sugar consumption, and hence promote both general and dental health, by integrating the common risk factor approach into the social determinant framework
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