In this paper thermo-hydrodynamic characteristics were investigated experimentally for a new type shell-helical coiled tube heat exchanger used as a storage tank of closed loop solar water heater system. Triple concentric helical coils were made of copper tubes of (12.5mm OD and 10mm ID) with coils diameter of (207, 152.2, 97mm) for outer, middle and inner coils respectively. The experiments were carried out during a clear sky days of (March and April 2012). The parameters studied in this work are: history of average temperature of shell side of the storage tank, collector heat gain, heat rejected from coils to shell side of the storage tank, collector efficiency, thermal effectiveness of the heat exchanger (storage tank), and pressure d

Thermal properties of soils are important in buried structures contact problems. Although laboratory is distinctly advantageous in measuring the thermal conductivity of soil under ideal condition, given the ability to simulate relatively large-scale in place of soil bed, the field thermal conductivity of soil is not yet commonly used in many types of research. The use of only a laboratory experiment to estimate thermal conductivity may be the key reason for overestimation or underestimation it. In this paper, an intensive site investigation including field thermal conductivity tests for six different subsoil strata were performed using a thermal probe method (TLS-100) to systematically understanding the effects of field dry density, water c

In this study, the radon gas concentration as well as the annual effective dose in leaves of the Malvasylvestris (Khabbaz) plant used in the traditional treatment and as food in Iraq, for this, it is necessary to evaluate the concentrations radon gas, which were measured using solid state nuclear track detectors (SSNTDs) CR-39 technique.  The  concentration and annual effective dose in samples were collected from Baghdad city ranged from minimum to maximum value 15.815 , 0.498 , 54.445 , 1.717  respectively, while the values of  concentration and annual effective dose in a sample collected from Karbala are 15.297 ,0.482 . These values of  concentration and annual effective dose less were compared with th

           Biosynthesis of nanoparticles has received considerable attention due to the growing need to develop environmentally benign nanoparticle synthesis processes that do not use toxic chemicals. Therefore, biosynthetic methods employing both biological agents such as bacteria and fungus or plant extracts have emerged as a simple and a viable alternative to chemical synthetic and physical method .It is well known that many microbes produce an organic material either intracellular or extracellular which is playing important role in the remediation of toxic metals through reduction of metal ions and acting as interesting Nano factories. As a result, in the present study Ag NPs were syn

The chemical composition of wastes of pressed grapes and found that the main components of wastes of pressed grapes, represented by the percentage of moisture was 6.47%, and the proportions are 3.71%. Either carbohydrates amounted to 85.77 %, either in fat models using petroleum ether Petroleum ether) was the increase of 0.27%. estimated the percentage of ash in the sampls was 3.78%, either fiber reached 69.47 %,, in addition to the test extracts towards the growth of seven types of bacteria, which included Bacillus subtilis, Bacillus cereus, Bacillus stearothermophilus, Escherishia coli, Staphylococcus aureus, Salmonella typhimurium and Pseudomonas fluorescens and yeast Candida albicans and Kluyveromyces marxianus, ( diffusion method ).

Experimental tests were conducted to investigate the thermal performance (cooling effect) of water mist system consisting of 5μm volume median diameter droplets in reducing the heat gain entering a room through the roof and the west wall by reducing the outside surface temperature due to the evaporative cooling effect during the hot dry summer of Baghdad/Iraq. The test period
was Fifty one days during the months May, June, and July 2012. The single test day consists of 16 test hours starting from 8:00 am to 12:00 pm. The results showed a reduction range of 1.71 to 15.5℃ of the roof outside surface temperature and 21.3 to 76.6% reduction in the daily heat flux entering the room through the roof compared with the case of not using w

Background: Mini implant stability is primarily related to local bone density; no studies have evaluated bone density related to mini implant placement for orthodontic anchorage between different age groups in the maxilla and the mandible. The present research aims to evaluate side, gender, age, and regional differences in bone density of the alveolar bone at various orthodontic implant sites. Materials and method: Fifty three individuals who were divided into two groups according to their age into: group I (ages 16-20 years) and group II (ages 21-29 years) had subjected to clinical examination, then 64-multislice computed tomography scan data were evaluated and bone density was measured in Hounsfield unit at 102 points (51 in the maxilla

Background: Disinfection and shaping of the canal with a combination of chem¬ical agents and endodontic instruments play an important role in the success of endodontic therapy. Eliminating the microorganisms within the pulp space is a critical and important objective in treating a tooth with apical periodontitis. This study was conducted to evaluate the antibacterial properties of herbal alternatives (Green tea and siwak extracts) as possible irrigants during endodontic treatment compared with the conventional irrigation solutions. Materials and methods: Salvadora Persica (siwak) and Green Tea solutions were prepared.An agar diffusion test was performed on Mueller-Hinton agar using the well diffusion method. The tested solutions (5.25% N

Specific microorganisms can produce bacterial nanocellulose (BNC), with acetic acid bacteria (AAB) being the most active producer. The family Acetobacteraceae includes the obligate aerobic, motile acetic acid bacteria. The BNC has attracted a lot of interest across a wide range of industries, including pharmaceuticals, due to its flexible characteristics, properties, and advantages. The present study was conducted to purify and characterize BNC produced from AAB isolated from apple vinegar. Bacterial nanocellulose was synthesized using a natural date palm liquid medium at pH 6 at 30°C for 8–10 days. The bacterial cellulose produced was then purified using a technique involving 0.1 M sodium hydroxide. To ascertain the surface mor