Both traditional and novel techniques were employed in this work for magnetic shielding evaluation to shed new light on the magnetic and aromaticity properties of benzene and 12 [n]paracyclophanes with n = 3–14. Density functional theory (DFT) with the B3LYP functional and all-electron Jorge-ATZP and x2c-TZVPPall-s basis sets was utilized for geometry optimization and magnetic shielding calculations, respectively. Additionally, the 6-311+G(d,p) basis set was incorporated for the purpose of comparing the magnetic shielding results. In addition to traditional evaluations such as NICS/NICSzz-Scan, and 2D-3D σiso(r)/σzz(r) maps, two new techniques were implemented: bendable grids (BGs) and cylindrical grids (CGs) of ghost atoms (Bqs). BGs allow for the recording of magnetic shielding from the bent ring levels of [n]pCPs, while CGs provide tubular magnetic shielding scan (TMSS) maps detailing the magnetic shielding from a cylindrical region above and below the ring frame. Our findings suggest that smaller [n]pCPs with n < 6 exhibit deviations in the magnetic shielding above and below the ring, indicating a broken electron delocalization under the ring. In contrast, larger [n]pCPs tend to behave similarly to benzene in terms of magnetic shielding. Moreover, we found that shorter polymethylene chains of [n]pCPs exhibit significantly higher magnetic shielding interactions with the ring. Both of the above techniques offer new and promising tools for characterizing nonplanar aromatic compounds, thereby contributing to a deeper understanding of their magnetic and electronic properties.
In this research, a group of gray texture images of the Brodatz database was studied by building the features database of the images using the gray level co-occurrence matrix (GLCM), where the distance between the pixels was one unit and for four angles (0, 45, 90, 135). The k-means classifier was used to classify the images into a group of classes, starting from two to eight classes, and for all angles used in the co-occurrence matrix. The distribution of the images on the classes was compared by comparing every two methods (projection of one class onto another where the distribution of images was uneven, with one category being the dominant one. The classification results were studied for all cases using the confusion matrix between every
... Show MoreThe international business environment faces many challenges, including the intensity of competition, the speed of expansion, and control of the market. This leads to its shadow on the local business environment, which prompted many economic units to adopt modern strategies, including mergers and acquisitions, for expansion and prosperity. The research was conducted to verify the role of internal audit in the governance of strategy operations (Mergers and acquisitions) and its reflection on management decisions and making them efficient and effective. Internal auditing is the independent variable related to the other variable, the governance of strategic operations and its impact on management decisions for strategic operations as a depende
... Show MoreEleven hymenopterous species: two braconids, seven eulophids and two pteromalids
parasitized the larvae of Phytomyza horticola Goureau. The activity of the parasites began at
the end of April and evidently increased during May. The female of the parasites fed and
parasitized mostly on the second and third larval instars of P. horticola . Diglyphus iseae
Walker and Cirrospilus vittatus Walker were dominant larval parasites. Chrysocharis
pentheus Walker and Pediobius acantha Walker were main pupal parasites.
Abstract:
The hotel sector is one of the most vital sectors exposed to risks, and the authorities concerned with control must take their active and influential role in putting the hotel sector on the right track and compatible with the internationally approved approaches, and the importance of auditing the performance of the hotel sector in light of the (Covid-19) pandemic is embodied in the fact that it gives a clear and realistic picture to the management and regulatory bodies about the performance and activities of this sector and the shortcomings and deviations that must be addressed, and also helps government decision makers to ob
... Show MoreBackground: Radiation therapy has the ability to destroy healthy cells in addition to cancer cells in the area being treated. However, when radiation combines with doxorubicin, it becomes more effective on breast cancer treatment. Objective: This study aims to clarify the effect of X-ray from LINAC combined with amygdalin and doxorubicin on breast cancer treatment, and the possibility of using amygdalin with X-ray instead of doxorubicin for the breast cancer treatment. Method: Two cell lines were used in this study, the first one was MCF-7 cell line and second one was WRL- 68 normal cell line. These cells were preserved in liquid nitrogen, prepared, developed and tested in the (place). The effect of three x-ray doses combined with a
... Show MoreThe competitive environment influences the increase in exercise intensity and hence adds to the growth of training and practice. The study objective.to identify the effect of competitive speed exercises on the effectiveness of skill performance and speed of counterattack for junior boxers, as well as to know the rate of development for these variables.Materials and methods. The research sample consisted of twelve up-and-coming Al-Najda Sports Club players who participated in the national tournament and were selected with care. They were placed into two groups, control and experimental, with six boxers each in the control and experimental groups. The two groups were assigned identical weights on purpose, and their ages range from 15 to 16 ye
... Show MoreAlO-doped ZnO nanocrystalline thin films from with nano crystallite size in the range (19-15 nm) were fabricated by pulsed laser deposition technique. The reduction of crystallite size by increasing of doping ratio shift the bandgap to IR region the optical band gap decreases in a consistent manner, from 3.21to 2.1 eV by increasing AlO doping ratio from 0 to 7wt% but then returns to grow up to 3.21 eV by a further increase the doping ratio. The bandgap increment obtained for 9% AlO dopant concentration can be clarified in terms of the Burstein–Moss effect whereas the aluminum donor atom increased the carrier's concentration which in turn shifts the Fermi level and widened the bandgap (blue-shift). The engineering of the bandgap by low
... Show MoreThis study aimed to statement jet stream and its impact in the anti-cyclone affecting the climate of Iraq. Through the use of simple correlation coefficient ( Pearson ) that there is a very strong relationship between high- Siberian and both of the jet stream especially during the winter or over the stations of North . Therefore we, observe the relationship be significant in most of the winter months , spring and autumn . Statistically significant , but are different between station and another station , while the study come to another Anti-ciyclon have a real ,significant and statistically relationship corrclation . But this relationship is less than which found in are much less it with the Siberian high , it depends on the type of stat
... Show MoreThe research aims to identify the bedroom furniture designs for children who are in ages range between (4-6) years and the rate of employing them in developing their aesthetic sense. To achieve this objective, the researchers developed the two research tools represented by a analysis-description form of bedroom furniture designs included a number of domains that were represented in the shapes, colors, and sizes of the furniture, as well as the availability of the safety factor, ease of use, cleaning and movement. As for the aesthetic sense scale included (30) paragraphs and alternatives (always, sometimes, never), they were distributed among a representative sample of (170) mothers of children were chosen randomly from (17) kindergartens
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