In this study, pebble bed as an absorber and storage material was placed in a south facing, flat plate air-type solar collector at fixed tilt angle of (45°). The effect of this material and differ- ent parameters on collector efficiency has been investigated experimentally and
theoretically. Two operation modes were employed to study the performance of the solar air heater. An inte- grated mode of continuous operation of the system during the period of (11:00 am – 3:00 pm) and non-integrated mode in which the system stored the solar energy through the day then used the stored energy during the period of (3:00 pm – 8:00 pm). The results of parametric study in case of continuous operating showed that the maximum average temperature difference of air between inlet and outlet sections observed on (0.018 kg/s) air mass flow rate were exceeded (17°C) and the maximum outlet temperature that got was exceeded (34°C) for the three months (December, January and February) of experiments. Average efficiency was ranged from 53% to 65%. In the case of storage and then operating, the maximum outlet air temperature was ranged from (27°C) up to (31°C) then
decreased with spend of energy to reach (13°C) to (18°C) and the maximum storage energy was (165.14 W) for the porosity of (0.29) , height of (20 cm) and (0.01 kg/s) mass flow rate. The results also, showed that the solar air collector supplied a solar heating fraction (SHF) with an average of (0.65) for a meeting room (3 * 4 * 7 m) located in Baghdad as a case study.
study the effect of radiation microwave (MW) in inhibition the growth of some types of bacteria in a minced meat and barker were exposed to MW for different times included (0, 10, 20, 30 and 40) sec.The results showed a high inhibition rate for 40 sec, reached to 100%. It is the other side studied the effect of microwave radiation against four types of bacteria included (Staphylococcus aureus, Escherichia coli, Proteus mirabilis and Klebsiella spp), when were exposed to for (0, 5, 10, 20, 30 and 40) sec the inhibition ratio reached to 100% in each of the Proteus mirabilis and Klebsiella spp at 30 sec and Staphylococcus aureus and Escherichia coli at 40sec. using MW in the sterilization media, such as Nutrient agar, Macconkey agar and Man
... Show MoreThe Research aims to determine role of The Intellectual capital in the performance of small and medium enterprises , to achieve this goal through a researcher from the theoretical literature and studies related to the construction of the scheme shows the hypothetical relationship between the variables, which was adopted by the independent variable intellectual capital, distributed four variable are:( human capital, structure capital ,customer capital, innovation capital) as well as four variable (the financial perspective, the customer perspective, process perspective ,the learning & growth perspective) The study were getting to many results as bellow :the intellectual capital in the small and intermediate p
... Show MoreAbstract
The curriculum is the major effective tool in achieving the goals of
education and society.
Many countries that want to reach the forefront of developed countries
through their curriculum have realized this fact. School text book, the
application assessment for knowing the rang of success or fail of this text
book in achieving the general aims. therefore this study aims at assessing the
principals and techniques of geography text book for fourth secondary class of
literary studying from the teachers point of view according to the fields of the
book, style of material, technical arrangement of the material, ethnical
arrangement the language of the book, style of the material, technical
arrang
Cupressus sempervirens L., Cupressaceae, that is known as evergreen cypress, Mediterranean cypress and in Arabic called “al -Sarw. It is an evergreen, medium sized, longevity, and wide distributed over all the world. The plant represents an important member of conifer plants which characterized with aromatic leaves and cones. Cupressus sempervirens have been ethnobotanical uses as an antiseptic, relief of cough, astringent, antispasmodic, wound healing and anti-inflammatory. Aims of this work are phytochemical analysis, isolation and structural identification of Quercitroside (quercitrin) and essential oil in Iraqi C. sempervirens. Isolation of quercitrin was
... Show MoreAbstract: This article is a comparative analysis of the concept and types of homonyms in Russian and Arabic. Homonyms are lexical units that have the same sound but different meanings. The study of homonymy in different languages can help reveal the features of the semantic structure and syntactic rules of each language. The article discusses the main aspects of homonymy in Russian and Arabic, as well as a comparative analysis of the types of homonyms that exist in both languages. The study includes an analysis of the semantic meanings of homonyms, their use in context, and possible differences in syntactic features that may affect their interpretation and perception by native speakers of these languages. The purpose of the article is to id
... Show MoreThe main objectives of this study were investigating the effects of the maximum size of coarse Attapulgite aggregate and micro steel fiber content on fresh and some mechanical properties of steel fibers reinforced lightweight self-compacting concrete (SFLWSCC). Two series of mixes were used depending on maximum aggregate size (12.5 and 19) mm, for each series three different steel fibers content were used (0.5 %, 1%, and 1.5%). To evaluate the fresh properties, tests of slump flow, T500 mm, V funnel time, and J ring were carried out. Tests of compressive strength, splitting tensile strength, flexural tensile strength, and calculated equilibrium density were done to evaluate mechanical properties. For reference mixes, the
... Show MoreThe research aims to develop physical exercises with auxiliary training tools that work to develop the explosive power of the arms and legs, and then find out their effect on the accuracy of shooting from free throw and correction from jumping of advanced basketball players, as the researchers found a problem that these players have weakness in the skill of throwing Free throwing and shooting by jumping calculated with two points as a result of adopting unhealthy physical and technical positions, which led to a lack of focus and accuracy, and thus negatively affected the performance technique of free throw and jump shot, as most teams use traditional exercises without the use of auxiliary training tools, and this topic gave researchers the
... Show MoreThe research includes the synthesis and identification of the mixed ligands complexes of M 2 Ions in general composition ,[M(Leu) 2 (SMX)] Where L leucine (C 6 H 13 NO 2 )symbolized (LeuH) as a primary ligand and Sulfamethoxazole C 10 H 11 N 3 O 3 S) symbolized (SMX)) as a secondary ligand . The ligands and the metal chlorides were brought in to reaction at room temperature in(v/v) ethanol /water as solvent containing NaOH. The reaction required the following [(metal: 2(Na Leu --): (SMX )] molar ratios with M(II) ions, Were M ( Mn ( II),Co (II),Ni(II),Cu( II),Zn (II),Cd(II)and Hg( The UV Vis and magnetic moment data revealed an octahedral geometry around M(II), The conductivity data show a non electrolytic nature of the complexes . The
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