The crystal structures of a new polymorph and seven new derivatives of 2-(1-phenyl-1H-1,2,3-triazol-4-yl)pyridine have been characterized and examined along with three structures from the literature to identify trends in their intermolecular contact patterns and packing arrangements in order to develop an insight into the crystallization behaviour of this class of compound. Seven unique C-H...X contacts were identified in the structures and three of these are present in four or more structures, indicating that these are reliable supramolecular synthons. Analysis of the packing arrangements of the molecules using XPac identified two closely related supramolecular constructs that are present in eight of the 11 structures; in all cases, the structures feature at least one of the three most common intermolecular contacts, suggesting a clear relationship between the intermolecular contacts and the packing arrangements of the structures. Both the intermolecular contacts and packing arrangements appear to be remarkably consistent between structures featuring different functional groups, with the expected exception of the carboxylic acid derivative 4-(4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl) benzoic acid (L11), where the introduction of a strong hydrogen-bonding group results in a markedly different supramolecular structure being adopted. The occurrence of these structural features has been compared with the packing efficiency of the structures and their melting points in order to assess the relative favourability of the supramolecular structural features in stabilizing the crystal structures.
Abstract
These experiments seek to investigate the effects of the fixed variations to the basic box plot on subjects' judgments of the box lengths. The study consists of two experiments, were constructed as an extension to the experiments carried out previously by Hussin, M.M. (1989, 2006). Subjects were asked to judge what percentage the shorter represented of the longer length in pairs of box lengths and give an estimate of percentage, one being a standard plot and the other being of a different box length and also varying with respect to other elements such as, box width or whisker length. When he (1989) suggested in the future research points (1, 2), the changing length of the st
... Show MoreIn this paper, the deterministic and the stochastic models are proposed to study the interaction of the Coronavirus (COVID-19) with host cells inside the human body. In the deterministic model, the value of the basic reproduction number determines the persistence or extinction of the COVID-19. If , one infected cell will transmit the virus to less than one cell, as a result, the person carrying the Coronavirus will get rid of the disease .If the infected cell will be able to infect all cells that contain ACE receptors. The stochastic model proves that if are sufficiently large then maybe give us ultimate disease extinction although , and this facts also proved by computer simulation.
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
... Show MoreBackground: Multiple sclerosis is a chronic autoimmune inflammatory demyelinating disease of the central nervous system of unknown etiology. Different techniques and magnetic resonance image sequences are widely used and compared to each other to improve the detection of multiple sclerosis lesions in the spinal cord. Objective: To evaluate the ability of MRI short tau inversion recovery sequences in improvementof multiple sclerosis spinal cord lesion detection when compared to T2 weighted image sequences. Type of the study: A retrospective study. Methods: this study conducted from 15thAugust 2013 to 30thJune 2014 at Baghdad teaching hospital. 22 clinically definite MS patients with clinical features suggestive of spinal cord involvement,
... Show MoreWater pollution is widely regarded as one of the most pressing global challenges, exacerbated by human progress in industrial, agricultural, and technological sectors. Wastewater often contains non-biodegradable heavy metals that accumulate in living organisms. This accumulation poses significant risks to both environmental ecosystems and human health. The structures and surface morphology were characterized by FTIR, UV-vis measurements, XRD, SEM, and AFM. TiO2 nanoparticles could remove heavy metal ions (Pb2+, Cd2+, and Cr3+) from two samples (laboratory samples and real samples from Babylon battery factory in Al-Waziriya, Baghdad/Iraq) and measured by AAS. The results indicated that the removal percentages of heavy metal ions by T
... Show MoreThis research aims to study the methods of reduction of dimensions that overcome the problem curse of dimensionality when traditional methods fail to provide a good estimation of the parameters So this problem must be dealt with directly . Two methods were used to solve the problem of high dimensional data, The first method is the non-classical method Slice inverse regression ( SIR ) method and the proposed weight standard Sir (WSIR) method and principal components (PCA) which is the general method used in reducing dimensions, (SIR ) and (PCA) is based on the work of linear combinations of a subset of the original explanatory variables, which may suffer from the problem of heterogeneity and the problem of linear
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In this research provide theoretical aspects of one of the most important statistical distributions which it is Lomax, which has many applications in several areas, set of estimation methods was used(MLE,LSE,GWPM) and compare with (RRE) estimation method ,in order to find out best estimation method set of simulation experiment (36) with many replications in order to get mean square error and used it to make compare , simulation experiment contrast with (estimation method, sample size ,value of location and shape parameter) results show that estimation method effected by simulation experiment factors and ability of using other estimation methods such as(Shrinkage, jackknif
... Show MoreWeibull distribution is considered as one of the most widely distribution applied in real life, Its similar to normal distribution in the way of applications, it's also considered as one of the distributions that can applied in many fields such as industrial engineering to represent replaced and manufacturing time ,weather forecasting, and other scientific uses in reliability studies and survival function in medical and communication engineering fields.
In this paper, The scale parameter has been estimated for weibull distribution using Bayesian method based on Jeffery prior information as a first method , then enhanced by improving Jeffery prior information and then used as a se
... Show MoreBackground: Due to the variations in tooth anatomy and size among different populations, this study aimed to compare the mesiodistal width of primary second molars in Iraqi children with the mesiodistal width of stainless-steel crowns from different companies. Materials and Methods: This cross-sectional study was conducted on 220 intact maxillary and mandibular primary second molars selected from boys and girls’ Iraqi children aged 8-9 years collected from different primary schools in Baghdad city. The mesiodistal dimensions of the selected teeth and the available maxillary and mandibular stainless-steel crowns from three different companies were measured by using a 3-D scanner, and then the whole measurements were calculated usin
... Show MoreThe existing investigation explains the consequence of irradiation of violet laser on the structure properties of MawsoniteCu6Fe2SnS8 [CFTS] thin films. The film was equipped by the utilization of semi-computerized spray pyrolysis technique (SCSPT), it is the first time that this technique is used in the preparation and irradiation using a laser. when the received films were processed by continuous red laser (700 nm) with power (>1000mW) for different laser irradiation time using different number of times a laser scan (0, 6, 9, 12, 15 and 18 times) with total irradiation time (0,30,45,60,75,90 min) respectively at room temperature.. The XRD diffraction gave polycrysta
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