Heterocyclic compounds are employed in many applications, and numerous researchers have created liquid crystals by adding heterocyclic to the structures of these molecules. This work includes the synthesis and characterization of new compounds that contain 5H-thiazolo [4,3-b][1,3,4] thiadiazol united in multiple steps, starting with the synthesis of the aldehyde compound [I] by reaction chloro ethyl acetate with 4-hydroxybenzaldehyde in the presence of ethanol and potassium carbonate, followed by reactions with thiosemicarbazide, mercapto acetic acid in sulphuric acid to produce compound [II] then reflux compound [II] with hydrazine hydrate to product compound [III], after that reaction the later compound with nalkoxybenzaldehyde [IV]n and a few drops of piperidine in THF as a solvent to produce new Schiff᾽s-bases compounds contain 5H-thiazolo [4,3-b] [1,3,4] thiadiazol unite [V]n, FTIR and 1HNMR spectroscopy were used to analyze the compounds, a polarized optical microscope (POM) and differential scanning calorimetry (DSC) were used to examine the characteristics of the liquid crystals. In the Smectic A (SmA) and nematic phases, liquid crystal characteristics are present in all compounds [V]n. In addition to the nematic phase, all compounds [V]n showed enantiotropic dimorphism in the SmA phase. It was revealed that compounds [V]n with 5H- thiazole [4,3-b] [1,3,4]thiadiazol unit, the rigid-rod core of Schiff bases, and the formation of a supramolecular hydrogen bond between the derivatives [V]n had liquid crystallinity, depending on the chain length of the alkoxy group as a terminal substituent.
This study delves into the realm of advanced cooling techniques by examining the performance of a two-stage parallel flow indirect evaporative cooling system enhanced with aspen pads in the challenging climate of Baghdad. The objective was to achieve average air dry bulb temperatures (43 oC) below the ambient wet bulb temperatures (24.95 oC) with an average relative humidity of 23%, aiming for unparalleled cooling efficiency. The research experiment was carried out in the urban environment of Baghdad, characterized by high temperature conditions. The investigation focused on the potential of the two-stage parallel flow setup, combined with the cooling capability of aspen pads, to surpass the limitat
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Breast cancer (BC) is first of the top 10 malignancies in Iraq. Dose‐volume histograms (DVHs) are most commonly used as a plan evaluation tool. This study aimed to assess DVH statistics using three‐dimensional conformal radiotherapies in BC in an adjuvant setting.
A retrospective study of 70 histologically confirmed women diagnosed with BC was reviewed. The study was conducted between November 2020 and May 2021, planning for treatment with adjuvant three‐dimensional conformal radiotherapies. The treatment plan used for each woman was based on an analysis of the volumetric dose, inclu
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The expansion of building blocks at the expense of agricultural land is one of the main problems causing climate change within the urban area of a city. The research came to determine these indicators, as a study was conducted on the expansion of the building blocks in three municipalities in the city of Baghdad for a period of four decades extended in the form of time cycles for the period (1981-2021) and using ArcMap GIS 10.7 technology. Then, the impact of this expansion on temperature rates was evaluated, as they are the most important climatic elements due to their significant effect on the rest of the elements. The results showed a clear, direct relationship between the increase in urban expansion rates and the corresponding r
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The integration of nanomaterials in asphalt modification has emerged as a promising approach to enhance the performance of asphalt pavements, particularly under high-temperature conditions. Nanomaterials, due to their unique properties such as high surface area, exceptional mechanical strength, and thermal stability, offer significant improvements in the rheological properties, durability, and resistance to deformation of asphalt binders. This research reviewed the application of various nanomaterials, including nano silica, nano alumina, nano titanium, nano zinc, and carbon nanotubes in asphalt modification. The incorporation of these nanomaterials into asphalt mixtures has shown potential to increase the stiffness and high-tempera
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Gundelia, a genus of flowering plants native to the Mediterranean region, particularly in Iraq, holds promise as a sustainable adsorbent for the treatment of dye-polluted water. This study explores the potential of Gundelia seeds (GS) waste as a biobased adsorbent for removing methylene blue dye from synthesized wastewater. Utilizing various analytical techniques, including scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction analysis (XRD), we assessed GS as an active adsorbent with performance comparable to fabricated and expensive composites. Key parameters such as pH (3-11), pH at the point of zero charge, temperature (298-328 K), dose (0.02-0.1 g), dye concentration (10-50 ppm), and
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The educational sector is one of the important sectors in the world, and it is considered one of the means of community development. In addition, it is one of the means of making the country’s renaissance and devel-opment because it represents the factory of thinking minds that make change. There is no doubt that this sector is the same as any other sector. The deficit in the studied scientific planning has been prolonged, which led to its deterioration, and the problems of education remain diverse and inherited from previous time periods, where the hierarchical cluster analysis was used on postgraduate students in universities in Iraq, except for Kurdistan region, and the number of universities that were included in the study was
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The study of the validity and probability of failure in solids and structures is highly considered as one of the most incredibly-highlighted study fields in many science and engineering applications, the design analysts must therefore seek to investigate the points where the failing strains may be occurred, the probabilities of which these strains can cause the existing cracks to propagate through the fractured medium considered, and thereafter the solutions by which the analysts can adopt the approachable techniques to reduce/arrest these propagating cracks.In the present study a theoretical investigation upon simply-supported thin plates having surface cracks within their structure is to be accomplished, and the applied impact load to the
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