The varied thermal conductivity (insulation) of silica aerogel with heating for different pH has been investigated, it has been depended on ambient pressure drying method in the preparing silica aerogel samples, also six different pH of samples (1, 2, 3, 7, 8 and 9) were treated under five degree of heating with (50,100,150,200 and 250) ᴼC. This technique is important to test the carry-outs hydrophobic silica to temperature without high-quality material changes in the basic characteristics. The hot-wire technique is used in this work to examine the thermal conductivity, Fourier Transform Infrared Spectroscopy (FTIR) depended to characterize the bonds and their artificial by heating. Results show that the samples affected by heating through decreasing the density leading to obtaining more insulation metal, moreover varied pH is an important role in thermal conductivity. The average thermal conductivity of all aerogel samples in this work is (0.01- 0.0061 mW m-10 C-1) this means that it is still below thermal conductivity for air equals to (0.02257) mW m-10 C-1 . Meanwhile, we concluded that the insulation property of silica aerogel is affected by heat treatment and gives it more thermal insulation property.
The auditor has a role in allocating joint costs in the gas industry, and the auditor's procedures are considered as systematic critical examination, analysis and evaluation of everything related to costs in general and joint costs in the gas industry in particular, with the aim of controlling the joint costs of gas industry products, and knowing the share of the cost of each product from the total industry costs Gas products reflect the reality of the company's performance by discovering weaknesses, defects and any errors, to ensure increased effectiveness and efficiency of the parties concerned with auditing them and imposing control and control over the company's resources, as well as
... Show Moreتحتل التنمية الزراعية في معظم بلدان العالم مكانة مهمة ومتميزة لما لها من دور مهم في الحياة الاقتصادية والاجتماعية .ففي البلدان المتقدمة كان هناك دعم كبير مالي وفني وعلمي وتكنولوجي من قبل الحكومات الى القطاع الزراعي على الرغم من الامكانيات المالية والفنية والادارية والتكنولوجية التي يمتلكها القطاع الخاص الزراعي.لذا فمن الضروري قيام الحكومات في البلدان الناميه بشكل عام والعراق بشكل خاص بتقديم كل اشكال
... Show Moreقال احد المربين ( أعطوني طفولة سعيدة ممتلئة وخذوا شباباً ناضجاً سليماً) ويعني بالطفولة السعيدة تلك الطفولة المشبعة بالحب والحنان وتلبية الحاجات المهمة للطفل حيث يتعلم الطفل من احضان العائلة بعض النواهي والاوامر حتى اذا اتسعت دائرة معارفه شملت الرفقة والعصبة حيث يبدأ الطفل بالتحرر شيئاً فشيئأ من الضوابط العائلية وينتقل مركز ولائه واخلاصه من العائلة الى العصبية وكلما تتوسع علاقات الطفل تزداد خبراته وت
... Show MoreAbstract
The relationship between population and development is one of the most interrelated relations in contemporary societies. Therefore it is important focus on the demographic aspects of the population and its integration with developmental aspects, because the population is the makers of development and responsible for its success. The population composition and their qualitative composition are important factors in development. This change in age rate is because of demographic operations which lasted for long time. The change we are talking about is happing currently in Arab cou
... Show MoreThe thesis discusses the concept of the new international regionalism that emerged after the growing effects and repercussions of globalization with its economic, political and security dimensions after the end of the Cold War and the crystallization of a different international system dominated by the United States of America, so that the major countries and actors in the international system realize the danger of globalization and move towards adopting regional arrangements to contain the negative effects of globalization. The Asia-Pacific model was chosen as a model for the study.
السياسة الخارجية الاسرائيلية تجاه افريقيا بعد انتهاء الحرب الباردة (دراسة حالة اثيوبيا)
The current study aims to examine the level of problems faced by university students in distance learning, in addition to identify the differences in these problems in terms of the availability of internet services, gender, college, GPA, interactions, academic cohort, and family economic status. The study sample consisted of (3172) students (57.3% females). The researchers developed a questionnaire with (32) items to measure distance learning problems in four areas: Psychological (9 items), academic (10 items), technological (7 items), and study environment (6 items). The responses are scored on a (5) point Likert Scale ranging from 1 (strongly disagree) to 5 (strongly agree). Means, standard deviations, and Multivariate Analysis of Vari
... Show MoreStumpff functions are an infinite series that depends on the value of z. This value results from multiplying the reciprocal semi-major axis with a universal anomaly. The purpose from those functions is to calculate the variation of the universal parameter (variable) using Kepler's equation for different orbits. In this paper, each range for the reciprocal of the semi-major axis, universal anomaly, and z is calculated in order to study the behavior of Stumpff functions C(z) and S(z). The results showed that when z grew, Stumpff functions for hyperbola, parabola, and elliptical orbits were also growing. They intersected and had a tendency towards zero for both hyperbola and parabola orbits, but for elliptical orbits, Stumpff functions
... Show MoreTannin acyl hydrolase as the common name of tannase is an inducible extracellular enzyme that causes the hydrolysis of galloyl ester and depside bonds in tannins, yielding gallic acid and glucose. The main objective of this study is to find a novel gallic acid and tannase produced by