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81.
A. F. M. Suaib Akhter Tawsif Zaman Arnob Ekra Binta Noor Selman Hizal Al-Sakib Khan Pathan 《Entropy (Basel, Switzerland)》2022,24(11)
The popularity of electric vehicles (EVs) is constantly increasing, as they use relatively greener, sustainable energy. However, it is a fact that the charging stations for EVs are yet to meet the demand. It could be a great solution if a peer-to-peer (P2P) charging system could be initiated by anyone who wants to make their garage’s charge points publicly available for commercial purposes, named a home charging station (HCS). In this work, our idea is to bring interested charging stations under a network of nodes and a blockchain-based management system, where the blockchain is responsible for ensuring the authenticity of both the charging stations and charge receiver. A cryptocurrency-based payment system has also been proposed to ensure transactions’ security, integrity, transparency, and immutability. A reputation management system is applied to maintain the quality of service. Miners with high processing power are used to alleviate lagging during block creation, supported by edge servers. The proposed system has been implemented by using virtual machines. A theoretical analysis is presented to assess the compatibility and possible cost requirements to implement the system in a real-world scenario. 相似文献
82.
Muhammad Zaman Muhammad Hammad Butt Waqar Siddique Muhammad Omer Iqbal Naveed Nisar Asma Mumtaz Hafiza Yusra Nazeer Abdulrahman Alshammari Muhammad Shahid Riaz 《Molecules (Basel, Switzerland)》2022,27(23)
Tenofovir alafenamide (TAF) is an antiretroviral (ARV) drug that is used for the management and prevention of human immunodeficiency virus (HIV). The clinical availability of ARV delivery systems that provide long-lasting protection against HIV transmission is lacking. There is a dire need to formulate nanocarrier systems that can help in revolutionizing the way to fight against HIV/AIDS. Here, we aimed to synthesize a polymer using chitosan and polyethylene glycol (PEG) by the PEGylation of chitosan at the hydroxyl group. After successful modification and confirmation by FTIR, XRD, and SEM, TAF-loaded PEGylated chitosan nanoparticles were prepared and analyzed for their particle size, zeta potential, morphology, crystallinity, chemical interactions, entrapment efficacy, drug loading, in vitro drug release, and release kinetic modeling. The fabricated nanoparticles were found to be in a nanosized range (219.6 nm), with ~90% entrapment efficacy, ~14% drug loading, and a spherical uniform distribution. The FTIR analysis confirmed the successful synthesis of PEGylated chitosan and nanoparticles. The in vitro analysis showed ~60% of the drug was released from the PEGylated polymeric reservoir system within 48 h at pH 7.4. The drug release kinetics were depicted by the Korsmeyer–Peppas release model with thermodynamically nonspontaneous drug release. Conclusively, PEGylated chitosan has the potential to deliver TAF from a nanocarrier system, and in the future, cytotoxicity and in vivo studies can be performed to further authenticate the synthesized polymer. 相似文献
83.
Shahida Sadiqi Muhammad Hamza Farooq Ali Sadia Alam Qismat Shakeela Shehzad Ahmed Asma Ayaz Sajid Ali Saddam Saqib Fazal Ullah Wajid Zaman 《Molecules (Basel, Switzerland)》2022,27(19)
Some soil microbes, with their diverse inhabitance, biologically active metabolites, and endospore formation, gave them characteristic predominance and recognition among other microbial communities. The present study collected ten soil samples from green land, agricultural and marshy soil sites of Khyber Pakhtunkhwa, Pakistan. After culturing on described media, the bacterial isolates were identified through phenotypic, biochemical and phylogenetic analysis. Our phylogenetic analysis revealed three bacterial isolates, A6S7, A1S6, and A1S10, showing 99% nucleotides sequence similarity with Brevibacillus formosus, Bacillus Subtilis and Paenibacillus dendritiformis. The crude extract was prepared from bacterial isolates to assess the anti-bacterial potential against various targeted multidrug-resistant strains (MDRS), including Acinetobacter baumannii (ATCC 19606), Methicillin-resistant Staphylococcus aureus (MRSA) (BAA-1683), Klebsiella pneumoniae (ATCC 13883), Pseudomonas aeruginosa (BAA-2108), Staphylococcus aureus (ATCC 292013), Escherichia coli (ATCC25922) and Salmonella typhi (ATCC 14028). Our analysis revealed that all bacterial extracts possess activity against Gram-negative and Gram-positive bacteria at a concentration of 5 mg/mL, efficiently restricting the growth of E. coli compared with positive control ciprofloxacin. The study concluded that the identified species have the potential to produce antimicrobial compounds which can be used to control different microbial infections, especially MDRS. Moreover, the analysis of the bacterial extracts through GC-MS indicated the presence of different antimicrobial compounds such as propanoic acid, oxalic acid, phenol and hexadecanoic acid. 相似文献
84.
85.
Binnatov K. G. Masharov S. I. Rybalko A. F. Safarov D. A. 《Russian Physics Journal》1993,36(12):1130-1134
The pattern of atomic ordering in ternary alloys A-B-(C) with an fcc lattice and L12 superstructure, in which the atoms of the component C occupy octahedral interstices, was investigated. The possible ordering diagrams of these systems were determined.Ural Polytechnical Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 42–46, December, 1993. 相似文献
86.
Summary We study the diffraction of SH-type elastic waves propagating along the plane interface between two dissimilar elastic half-spaces.
It is assumed that the contact between the half-spaces is perfect except for a part of semi-infinite extension where the contact
is loosely coupled. We use the Wiener-Hopf technique to obtain the diffracted field in a closed form. 相似文献
87.
A simple and sensitive stability indicating high performance liquid chromatography method was developed for quantification of Daclatasvir hydrochloride in bulk and tablet dosage forms. The analysis was performed on water symmetry analytical column (150 mm?×?3.9 mm, 5 µm), packing octyl silica (Si-[CH2]7-CH3) C8. Mobile phase containing potassium phosphate buffer (pH 2.0) and acetonitrile (38: 62) v/v was used at flow rate 0.7 mL min?1 for isocratic elution. Detection was performed on 304 nm using UV detector. The method was validated appropriately according to the requirements of United State Pharmacopeia and International Conference on Harmonization guideline Q2 (R1). Recovery, precision, linearity and specificity of the method were assured. The correlation coefficient for linearity ranged from 2 to 24 µg mL?1 was (r?>?0.9999). The limits of detection and quantification of Daclatasvir were 0.08 and 0.28 µg mL?1, respectively. Stability studies of Daclatasvir were performed under various stressed conditions, i.e., hydrolytic (acidic, basic and neutral), oxidation, photolytic and thermal conditions, according to International Conference on Harmonization Q1A (R2) and QIB Guidelines. The degradation products were resolved using proposed method and further characterized by MS, NMR and IR spectroscopic analyses. The proposed method was successfully applied to assay determination of bulk drugs and tablet dosage forms. 相似文献
88.
R. F. Talipov R. R. Muslukhov I. M. Safarov F. A. Yamantaev M. G. Safarov 《Chemistry of Heterocyclic Compounds》1995,31(5):530-533
Mixtures of 3-trif uoroacetoxy- and 3-chloro-4-alkyltetraliydrofurans were synthesized by the reaction of a series of-olefins with formaldehyde in trifuoroacetic acid and trimethylchlorosilane.The characteristics of the mixtures of cis and trans isomers are given, and the nD
20 values are given for the trans isomers.Bashkir State University, Institute of Fine Organic Synthesis. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 605–608, May, 1995. Original article submitted November 4, 1994; revision submitted May 10, 1995. 相似文献
89.
Guangfu Wang Lixia Yan Shahid Zaman Minjie Zhang 《International journal of quantum chemistry》2020,120(18):e26334
The connective eccentricity index (CEI) of a graph G is defined as , where εG(.) denotes the eccentricity of the corresponding vertex. The CEI obligates an influential ability, which is due to its estimating pharmaceutical properties. In this paper, we first characterize the extremal graphs with respect to the CEI among k-connected graphs (k-connected bipartite graphs) with a given diameter. Then, the sharp upper bound on the CEI of graphs with given connectivity and minimum degree (independence number) is determined. Finally, we calculate the CEI of two sets of molecular graphs: octane isomers and benzenoid hydrocarbons. We compare their CEI with some other distance-based topological indices through their correlations with the chemical properties. The linear model for the CEI is better than or as good as the models corresponding to the other distance-based indices. 相似文献
90.
A coordination polymer with a novel structural motif consisting of stacks of infinite ladders interpenetrated by bundles of infinite chains is described; geometrical arguments are made for the requirements that can lead to such interpenetration as a function of ligand dimensions. 相似文献