Search

Using a chemical spray technique, an n-type WO3 polycrystalline thin film was prepared with optimizing parameters (molarity concentration of 80 mM and a substrate temperature of 350 °C). Study the physical properties of WO3 thin film via UV-Visible spectroscopy, XRD, Field Emission-Scanning Electron Microscope, Energy Dispersive X-ray Spectroscopy, Atomic Force Microscopy, and current-voltage. Tungsten oxide was deposited on glass surfaces at different molarities ranging from 50–90mM. In the UV-Visible spectrum of the WO3 thin film, it was found that the transmittance, reflectivity, and energy gap decreased (78%–53%), (9.63%–5.02%), and (3.40eV–2.63 eV), respectively. The X-ray diffraction of the WO3 film at the optimized was poly-crystalline and had a monoclinic phase, and the preferred orientation (hkl) was 200 at 2 = 24.19. From the image FESEM and EDX, it was found that it has a multi-fibrous network. The average diameter of the fiber is 266 nm, and the ratio of tungsten to oxygen (W/O) is 2.6, with a stoichiometric of 68.6% at the 80 mM concentration. The Atomic Force Microscopy shows that the WO3 thin layer has a nanostructure. The average surface roughness was 5.3 nm, and the Root Mean Square was 8.6 nm. The WO3 film had the lowest resistivity value of 2.393 × 108W cm, and the activation energy was 0.298 eV, among the parameter of the current voltage at substrate temperature and concentration optimum.

One of the most affordable and readily available energy sources is solar energy. Humanity is in danger due to the lack of freshwater. Finding novel approaches to these issues that make use of solar energy has grown in popularity as a research area. The previous work presented was made to cool solar cells to increase their performance. The reverse-osmosis system is then fed by the cooling water. This study investigated the ideal conditions for cooling water fed into a reverse-osmosis system. Two identical solar cells were used for the current experiments. Water was used to cool one of the two cells. Measurements were made of the cell surface temperature, output voltage, current, and power. It was calculated to find the electrical efficiency of both cooled and uncooled cells. The cooled cell produced a maximum power of 6.75 W, according to the results. At 1:00 p.m., the gain power reached its maximum. The greatest efficiency gain, 50.2%, was observed at 4:00 p.m. Throughout the work that was presented, there was an 8% decrease in cell surface temperature. The water application value engine (WAVE) was used to simulate a reverse-osmosis system. The program's findings demonstrated that energy consumption dropped as feed water temperature rose. The findings of a case study conducted in a real water-desalination plant were confirmed. [ABSTRACT FROM AUTHOR]

The current study involved measuring the physical and chemical characteristics of the water of the Tigris River in Tikrit and its suburbs at five different sites for a period of six months. The results indicated significant variations across the study sites: turbidity ranged from 8,437 to 16,301NTU; conductivity from 191,833 to 202.38µS/cm; TDS from 382.77 to 412,944mg/L, and pH from 6.040 to 6.493. Dissolved oxygen levels ranged between 9.300 and 11.53mg/L, while biological oxygen demand varied from 2,922 to 4,016mg/L, and total alkalinity ranged from 56,888 to 62,444mg/L. Total hardness of the water at the sites ranged from 80,167 to 91,056mg/L, calcium hardness from 59,222 to 64,778mg/L, and magnesium hardness from 17,611 to 30,722mg/L. Furthermore, phosphate concentrations ranged from 3,339 to 3,449µg of phosphate atom/L, and silica concentrations from 3.40 to 4.58µg/L. While nitrite values ranged from 0.467 to 0.477µg of nitrogen atom/L. The results for monthly changes showed that the turbidity values were 4,278 to 24,644NUT, and the pH values were 5,469 to 7,250, while the dissolved oxygen values were 8.86 to 11.24mg/L, and the biological oxygen demand value was 3,500 to 3,826mg/L. Moreover, the results showed that the total hardness values ranged from 71,733 to 113,200mg/L, and phosphate values ranged from 2,998 to 4,808µg of phosphate atom/L, while nitrite values ranged from 0.454 to 0.532µg of nitrogen atom/L. [ABSTRACT FROM AUTHOR]

To prevent or reduce the drawback effect and prolong the life of PVC and preserve its composition and efficiency, compounds are incorporated with PVC. In this work, three highly aromatic anti-cancer Schiff base compounds in symbol (C2, C3 and C5) were applied to photostabilize of PVC against photodegradation, by added it to the polymer in the form of Schiff bases, to increase the stability of polymer when irradiated with ultraviolet (UV) light, (λmax = 365 nm) at 30 ºC, with the intensity of the light wavelength at 1920 lux for a long duration. The PVC was blended with Schiff's base in concentration (0.5 %wt.), with thickness films (40 μm) were made from the blended materials. Several methods were used, including infrared spectroscopy, surface examination of irradiated films to know the effect of additives on PVC photostabilization and conductivity of films were measured by LCR meter. The results showed that the additives significantly reduced the photodegradation of PVC. C2 compound as additive, stabilize PVC more than other additives, it can absorb harmful radiation, deactivate hydrogen chloride, and scavenge high-energy species such as peroxides. Several mechanisms of photostabilization for C2 compound have been suggested. Therefore it is acting as stabilizers for PVC. [ABSTRACT FROM AUTHOR]

The microbial polymeric biofilm matrix belongs to a single microbial species or multiple microbial species that are directly or indirectly responsible for over 80% of all microbial infections. A six-month laboratory study was conducted to extract the biofilms from Klebsiella pneumoniae and Candida albicans isolates to study their properties and their toxic effects on blood lymph. The results showed that treating 20 samples of K. pneumoniae and 100 samples of C. albicans biofilms with gentamicin and fluconazole antibiotics led to the inhibition of biofilm production for all the studied isolates by 74.9% and 64.32%, respectively. The results of screening electron microscopy (SEM) showed that the diameters of some K. pneumoniae cells ranged from 0.18-0.47 µm, while the diameters of C. albicans cells ranged from 121.82-133.89 nm. Fourier-Transform Infrared Spectroscopy (FTIR) of biofilmrevealed the presence of compounds in the matrix of the biofilm of K. pneumoniae, such as mannans and carboxylate (C=O), indicating the presence of sugar acids, proteins, and hydrocarbons. The results of the analysis of the biofilm produced by C. albicans showed a high percentage of sugars, as well as carboxyl and 2' acetyl. The Biofilm produced by K. pneumoniae inhibited the lymphocytes by 34.8% from the 150 μL sample. The lymphocytes showed higher inhibitory activity against C. albicans alone and against the combined biofilm of C. albicans and K. pneumoniae, where the highest percentage of inhibition reached 74.82% and 69.5% for the two treatments, respectively, at a sample volume of 100 µL. This leads to the conclusion that the biofilms of K. pneumoniae and C. albicans are responsible for over 80% of microbial infections. The use of antibiotics such as gentamicin and fluconazole led to the inhibition of biofilm production by up to 74.9% and 64.32% respectively, indicating the effectiveness of antibiotics in controlling biofilm growth. [ABSTRACT FROM AUTHOR]

The study sought to examine the impact of financial structure on the market value added of Iraqi tourism companies. The study adopted a quantitative approach by analyzing the financial data of a sample of Iraqi tourism companies for the period from 2004 to 2018. To measure the financial structure, three variables were used: Leverage Ratio, Equity to Total Assets Ratio and Short - Term Financing to Total Equity Ratio. The paper found that tourism companies differ in their reliance on debt in relation to property rights. It also found that there is a limited dependence of most of the study sample companies on fixed-cost loans in finance, in particular longterm loans. In addition, any improvement in the market value of the entity in relation to it carrying value will lead to an increase in the market value added. This study provides a better understanding of the relationship between financial structure in tourism companies and their market value added for researchers, practitioners and managers in the sector. Moreover, the results of this study are a working guide for financial managers in tourism companies and for the general investors in the tourism sector in determining the structure of financing or when making decisions to borrow or invest, because such decisions will directly affect the market value added of the company and the price of its shares in the financial markets. This study is one of the first studies that discuss the relationship of financial structure to market value added in the tourism sector in Iraq and is thus the starting point in exploring the determinants of financial structure in this important sector.