PURKH (E-Journals)
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Ransomware: A New Era of Digital Terrorism
Get PDFThis work entails the study of ten nasty ransomwares to reveal out the analytical similarities and differences among them, which will help in understanding the mindset of cyber crooks crawling over the dark net. It also reviews the traps used by ransomware for its distribution and side by side examining the new possibilities of its dispersal. It conclude by divulging inter-relationship between various distribution approaches adopted by ransomwares and some attentive measures to hinder the ransomware and supporting alertness as ultimate tool of defense at user’s hand
Annual Reviewer Acknowledgement
No full textComputer Reviews Journal (2018).
The Editorial team of the would like to thank the following reviewers for their work in refereeing manuscripts during 2018
An Ensemble Model of Machine Learning Algorithms for the Severity of Sickle Cell Disease (Scd) Among Paediatrics Patients
Get PDFThis study was motivated at developing an ensemble of 3 supervised machine learning algorithms for the assessment of the severity of sickle cell disease (SCD) among paediatric patients. The study collected data from a tertiary hospital in south-western Nigeria following the identification of variables required for assessing the severity of SCD. The study also adopted the use of 3 supervised machine learning algorithms namely: naïve Bayes (NB), C4.5 decision trees (DT) and support vector machines (SVM) for creating the ensemble model using a 10-fold cross validation technique. The models were created by adopting the algorithms in isolation and in combination of 2 and 3 which were compared. The developed models were evaluated in order to present the model with the best performance. The results of the study showed that using an ensemble of DT and NB alone provided the best performance. The study has implications in presenting a model for improving the assessment of the severity of SCD among paediatric patients in Nigeria
Some Physical Properties of Cubic System Miscellaneous Compounds
Get PDFThe norm of elastic constant tensor and the norms of the irreducible parts of the elastic constants of different types of cubic system miscellaneous compounds are calculated. The relation of the scalar parts norm and the other parts norms and the anisotropy of these compounds are characterized. The norm ratios are used to study anisotropy of these compounds
Annual Reviewer Acknowledgement
No full textThe Editorial team of the would like to thank the following reviewers for their work in refereeing manuscripts during 2018
Progress on Modified Polyurethane for Preservation of Paper Cultural Relic
Get PDFPaper cultural relics have extremely high value in research and collection. However, as the time goes on and the environment changes, there will be unfavorable conditions on paper relics, like yellowing, moulding, chalking, aging and embrittlement to some extent. Nowadays, the protection and repair of paper cultural relics are the research emphasis in the field of relics protection. The modified Polyurethane (PU) is an effective material for protecting paper cultural relics and overcome the disadvantages of traditional PU material, including poor polar-solvent resistance and poor heat resistance. Therefore, in this article, the synthesis, properties, applications of modified PU material were summarized and prospects for the research development in the future were look forward
Structural and vibrational properties of three species of anti-histaminic diphenhydramine by using DFT calculations and the SQM approach: Structural and vibrational properties of anti-histaminic diphenhydramine agent
No full textIn the present work, the free base, cationic and hydrochloride species of the anti-histaminic diphenhydramine drug were theoretically studied by using the hybrid B3LYP/6-311++G** calculations in the gas phase and the experimental available infrared and Raman spectra for the hydrochloride form in the solid phase. Here, the 114, 117 and 120 vibration normal modes expected for the free base, cationic and hydrochloride species of DPH, respectively were reported together with their corresponding force fields at the same level of theory. The atomic NPA and Mulliken charges, molecular electrostatic potentials, bond orders, main delocalization energies and topological properties were studied for those three species of DPH. The results show that the cationic species presents the higher dipole moment value, as expected because this species is charged while the presence of Cl atom justifies the higher volume observed for the hydrochloride species. Very good correlations were found between the theoretical and experimental available geometrical parameters for the hydrochloride species of DPH. The NBO and AIM analyses show the high stability of the hydrochloride species due to the presence of one H bond and two halogen bonds different from only one H bond observed in other two species of DPH. The evaluations of the frontier orbitals show that the hydrochloride form is the most reactive due to its low gap value while the cationic form is the less reactive. The comparisons of the gap values for the three species of DPH with other similar species containing the N-CH3 groups, such as the tropane, cocaine and morphine alkaloids, have showed that the three species of DPH have practically the same reactivities while in the three forms of those alkaloids the values are very different among them, presenting the three forms of tropane the lowest reactivities. Hence, the three species of DPH, with two N-CH3 groups, have apparently the same reactivities than the cationic form of cocaine. Finally, the vibrational analyses for the three species of DPH evidence that the presence of two halogen bonds and one H bond in the hydrochloride species of DPH, due to the Cl atom, produce a shifting of deformation bR1(A1) ring mode of a ring with respect to the other bR1(A2) while in the free base and cationic the deformation rings modes of both rings are predicted at the same wavenumbers
Structural Effects of Silicon Substitution on Hydroxyapatite Structure with High Substitution Ratio By Rietveld’s Analysis
Get PDFThe silicon-substituted hydroxyapatite (Si-HA) with three different Si-substitution levels were synthesized via aaqueous precipitation method, in the absence of any surfactants and organic solvents. The composition of the Si-substituted HA phases and effect of silicon substitution on the crystal structurewere investigated by Rietveld refinements from powder X-ray diffraction data. The results show that the final compounds are oxy-hydroxyapatites, a chemical formula for the Si-substituted HA phases with indication of the incorporated silicate amount is proposed
Synthesis And Characterization Of Methacrylate Based Polymeric Additives For Crude Petroleum Oil
Get PDF Wax deposition in crude oil especially at low temperature causes serious problem during its storage and transportation since this deposited wax gradually immobilizes the oil. Thus, waxy crude oils have high pour point resulting lots of handling problems. To solve this problem, a number of flow improvers (FI) or pour point depressants (PPD) have been prepared. But still it is a challenging aspect of this research area to find out the perfect chemistry with an improved efficiency and cost effective additives over the conventional one. In this context and in continuation of our effort for the development of additive systems for lube and crude oils, homo polymer of decyl methacrylate and its copolymers with styrene and vinyl acetate at different percentage composition in the presence of benzoyl peroxide (BPO) as initiator have been prepared. All the prepared polymers are characterised by FT-IR, NMR and Gel Permeation Chromatography (GPC). The prepared additives showed excellent performance as flow improver (FI) or pour point depressant (PPD) in crude oil
The Emergence and Development of Sino-Nigeria Economic Relations: An Analysis
Get PDFThe paper examines the emergence and development of bilateral trade and investment between Nigeria and china, and analyses the level and volumes of imports and exports between the two states. By adopting the secondary methodology of library research, findings show that, the volume of trade has virtually increased between the two partners and albeit, it is lopsided, the two benefit from the bilateral relations. The paper concludes that, Nigeria’s imports from china are more diversified than the exports as a result of monoculturalism and lack of industrialization. The paper recommends establishing a joint bilateral commission for the two states and monitoring of the importation and exportation of fake and substandard goods