Kombucha(Khubdat Humza) is composed of yeast and acetic acid bacteria especially, Acetobacter xylinum which forms a cellulose pellicle on tea broth. Kombucha(Khubdat Humza) produces bacterial cellulose pellicles, with unique purity and fine structure. It can be used in many forms, such as an emulsifier, stabilizer, dispersing agent, thickener and gelling agent but these are generally subsidiary to its most important use of holding on to water. Recently, bacterial cellulose is used in many special applications such as a scaffold for tissue engineering of cartilages and blood vessels, also for artificial skin for temporary covering of wounds, as well as its used in the clothing industry. The yield of cellulose produced were investigated in this study, the tea broth was fermented naturally over a period of up to 20 days in the presence of different amounts of black tea and sucrose as nitrogen and carbon sources. 10g/L black tea produced highest weight of bacterial cellulose (55.46g/L) and 100g/L sucrose also exhibited high amount of pellicle (63.58g/L). Temperature was essential factor on growth, where the pellicle was formed at range (20°C - 50°C) and higher temperature over 50°C depressed the bacterial cellulose formation. The bacterial cellulose production increased with the increase of surface area and depth of the broth. Findings from this study suggest that the yield of cellulose depends on many factors that need to be optimized to achieve maximum yield.
This study sought to give a general picture of the organizations and formations of the ground forces of the Abbasid army in its first era, in preparation and armament and continuous development of the mechanisms to help maintain the moral and spiritual morale in the fighting.
Therefore, the caliphs' interest in building the army, organizing it, arming it, choosing competent leaders, and providing them with various weapons in terms of production and storage, as well as taking care of fortifying the cities and gaps in determination and determination, and embarked on construction and restoration, where amazing speed and acted according to the circumstances. During the first Abbasid era, there were significant developments in the military
Water one of the most important sources Which is no doubt essential for life surviving, water is vital in many sectors of life e.g. ( agriculture, industrial, power and so many things can’t be restricted on the mentioned items, water has become major problem facing the world today. Competition over water resources between nations has made it as a vital commodity and a justification for waging wars against its neighbor’s countries, there are currently 263 rivers that either cross or demarcate international political boundaries. Geographically, Europe has the largest number of international basins (69), followed by Africa (59), Asia (57), North America (40), and South America (38).The absolute numbers of international basins, as well as t
... Show MoreThe impacts of harvested cropland in the double cropping region (DCR) of the northern China plains (NCP) on the regional climate are examined using surface meteorological data and the satellite-derived normalized difference vegetation index (NDVI) and land surface temperature (LST). The NDVI data are used to distinguish the DCR from the single cropping region (SCR) in the NCP. Notable increases in LST in the period May–June are found in the area identified as the DCR on the basis of the NDVI data. The difference between the mean daily maximum temperature averaged over the DCR and SCR stations peaks at 1.27°C in June. The specific humidity in the DCR is significantly smaller than in
This study examines the impact of adopting International Financial Reporting Standards (IFRS) on the value of economic units. Given the global push toward standardization of financial reporting to enhance financial statement transparency, comparability, and reliability, this research seeks to understand the implications of these standards for economic valuation within a region characterized by its unique economic and regulatory challenges. A questionnaire was distributed to 86 Iraqi academics specializing in economics, accounting, and finance to collect their views on the impact of adopting international financial reporting standards. Through careful statistical analysis, the study concluded that applying international financial reporting s
... Show MoreIn this research, we sought to identify the nature of the relationship between the exchange rate of the Chinese yuan and the value of Chinese exports, through the formulation of a standard model based on the model of common integration, and based on the data of the study and using the test "Angel-Granger" It reflects the relationship between the two research variables, through which the relationship between the RMB exchange rate and the value of Chinese exports was estimated during the period 1978-2017.
Thin films of (Cu2S)100-x( SnS2 )x at X=[ 30,40, &50)]% with thickness (0.9±0.03)µm , had been prepared by chemical spray pyrolysis method on glass substrates at 573 K. These films were then annealed under low pressure of(10-2) mbar ,373)423&473)K for one hour . This research includes , studying the the optical properties of (Cu2S)100-x-(SnS2)x at X=[ 30,40, &50)]% .Moreover studying the effect of annealing on their optical properties , in order to fabricate films with high stability and transmittance that can be used in solar cells. The transmittance and absorbance spectra had been recorded in the wavelength range (310 - 1100) nm in order to study the optical properties . It was found that these films had direct optical band
... Show MoreBackground:The demand for esthetic orthodontic appliances is increasing so that the esthetic orthodontic archwires were introduced. This in vitro study was designed to evaluate the surface roughness offiber-reinforced polymer composite (FRPC) archwires compared to coated nickel-titanium (NiTi) archwires immersed in artificial saliva. Materials and Methods:Three types of esthetic orthodontic archwires were used: FRPC (Dentaurum), Teflon coated NiTi (Dentaurum) and epoxy coated NiTi (Orthotechnology). They were round (0.018 inch) in cross section and cut into pieces of 15 mm in length.Forty pieces from each type were divided into four groups; one group was left at a dry condition and the other three groups were immersed in artificial saliva (
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