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181.
Ameer Fawad Zahoor Muhammad Yousaf Rabia Siddique Sajjad Ahmad Syed Ali Raza Naqvi Sayyad Muhammad Ali Rizvi 《合成通讯》2017,47(11):1021-1039
Enoxacin, levofloxacin, and gatifloxacin represent one of the most important prerogative scaffolds in drug development. They possess broad spectrum antimicrobial and anti-inflammatory activities. They inhibit bacterial growth by blocking their topoisomerase enzyme which is necessary for the proper functioning of bacterial DNA. In this article, we have reviewed the synthetic approaches involved in the synthesis of derivatives of enoxacin, levofloxacin, and gatifloxacin. 相似文献
182.
Abdul Jabbar Khan Muhammad Sajjad Shaukat Khan Muhammad Khan Abdul Mateen Syed Shaheen Shah Numan Arshid Liang He Zeyu Ma Ling Gao Guowei Zhao 《Chemical record (New York, N.Y.)》2024,24(1):e202300302
As supercapacitor (SC) technology continues to evolve, there is a growing need for electrode materials with high energy/power densities and cycling stability. However, research and development of electrode materials with such characteristics is essential for commercialization the SC. To meet this demand, the development of superior electrode materials has become an increasingly critical step. The electrochemical performance of SCs is greatly influenced by various factors such as the reaction mechanism, crystal structure, and kinetics of electron/ion transfer in the electrodes, which have been challenging to address using previously investigated electrode materials like carbon and metal oxides/sulfides. Recently, tellurium and telluride-based materials have garnered increasing interest in energy storage technology owing to their high electronic conductivity, favorable crystal structure, and excellent volumetric capacity. This review provides a comprehensive understanding of the fundamental properties and energy storage performance of tellurium- and Te-based materials by introducing their physicochemical properties. First, we elaborate on the significance of tellurides. Next, the charge storage mechanism of functional telluride materials and important synthesis strategies are summarized. Then, research advancements in metal and carbon-based telluride materials, as well as the effectiveness of tellurides for SCs, were analyzed by emphasizing their essential properties and extensive advantages. Finally, the remaining challenges and prospects for improving the telluride-based supercapacitive performance are outlined. 相似文献
183.
Inverted polymer solar cells with employing of electrochemical-anodizing synthesized TiO_2 nanotubes
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An inverted structure of polymer solar cells based on Poly(3-hexylthiophene)(P3HT):[6-6] Phenyl-(6) butyric acid methyl ester(PCBM) with using thin films of TiO_2 nanotubes and nanoparticles as an efficient cathode buffer layer is developed. A total of three cells employing TiO_2 thin films with different thickness values are fabricated. Two cells use layers of TiO_2 nanotubes prepared via self-organized electrochemical-anodizing leading to thickness values of 203 and 423.7 nm, while the other cell uses only a simple sol–gel synthesized TiO_2 thin film of nanoparticles with a thickness of 100 nm as electron transport layer. Experimental results demonstrate that TiO_2 nanotubes with these thickness values are inefficient as the power conversion efficiency of the cell using 100-nm TiO_2 thin film is 1.55%, which is more than the best power conversion efficiency of other cells. This can be a result of the weakness of the electrochemical anodizing method to grow nanotubes with lower thickness values. In fact as the TiO_2 nanotubes grow in length the series resistance(Rs) between the active polymer layer and electron transport layer increases, meanwhile the fill factor of cells falls dramatically which finally downgrades the power conversion efficiency of the cells as the fill factor falls. 相似文献
184.
A bi-disperse granular gas in an asymmetrical two-compartment system is studied experimentally. The presence of asymmetry within the range of our experimental parameters results in a directed segregated state and a directed clustering state. This deterministic system does not depend on the initial conditions. A modified flux model based on Lohse's flux model for bi-disperse granular gases is derived. The modified flux model explains qualitatively the experimental results. 相似文献
185.
Noelia M. Sanchez-Ballester Flavien Sciortino Sajjad Husain Mir Gaulthier Rydzek 《Molecules (Basel, Switzerland)》2022,27(10)
The ionization degree, charge density, and conformation of weak polyelectrolytes can be adjusted through adjusting the pH and ionic strength stimuli. Such polymers thus offer a range of reversible interactions, including electrostatic complexation, H-bonding, and hydrophobic interactions, which position weak polyelectrolytes as key nano-units for the design of dynamic systems with precise structures, compositions, and responses to stimuli. The purpose of this review article is to discuss recent examples of nanoarchitectonic systems and applications that use weak polyelectrolytes as smart components. Surface platforms (electrodeposited films, brushes), multilayers (coatings and capsules), processed polyelectrolyte complexes (gels and membranes), and pharmaceutical vectors from both synthetic or natural-type weak polyelectrolytes are discussed. Finally, the increasing significance of block copolymers with weak polyion blocks is discussed with respect to the design of nanovectors by micellization and film/membrane nanopatterning via phase separation. 相似文献
186.
A new magnetic nanocatalyst (Fe3O4@KCC-1-npr-NH2) was synthesized directly through the reaction of Fe3O4@KCC-1 with (3-aminopropyl) triethoxysilane (APTES) using a hydrothermal protocol. Prepared nanocomposite was used as a magnetically reusable nanocatalyst for an efficient synthesis of a broad range of sulfonamide derivatives in water as a green solvent at room temperature and the products are collected by filtration with excellent yields (85–97%). The nanocatalyst could be remarkably recovered and reused after ten times without any significant decrease in activity. This mild and simple synthesis method offers some advantages including short reaction time, high yield and simple work-up procedure. 相似文献
187.
Dr. Hamidreza Arandiyan Dr. Sajjad S. Mofarah Dr. Yuan Wang Dr. Claudio Cazorla Dr. Deshetti Jampaiah Dr. Magnus Garbrecht Prof. Karen Wilson Prof. Adam F. Lee Prof. Chuan Zhao Prof. Thomas Maschmeyer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(58):14418-14426
Perovskite oxides are regarded as promising electrocatalysts for water splitting due to their cost-effectiveness, high efficiency and durability in the oxygen evolution reaction (OER). Despite these advantages, a fundamental understanding of how critical structural parameters of perovskite electrocatalysts influence their activity and stability is lacking. Here, we investigate the impact of structural defects on OER performance for representative LaNiO3 perovskite electrocatalysts. Hydrogen reduction of 700 °C calcined LaNiO3 induces a high density of surface oxygen vacancies, and confers significantly enhanced OER activity and stability compared to unreduced LaNiO3; the former exhibit a low onset overpotential of 380 mV at 10 mA cm−2 and a small Tafel slope of 70.8 mV dec−1. Oxygen vacancy formation is accompanied by mixed Ni2+/Ni3+ valence states, which quantum-chemical DFT calculations reveal modify the perovskite electronic structure. Further, it reveals that the formation of oxygen vacancies is thermodynamically more favourable on the surface than in the bulk; it increases the electronic conductivity of reduced LaNiO3 in accordance with the enhanced OER activity that is observed. 相似文献
188.
Batool Saima Nawaz M. Saif Rai Sajjad Rana Shafia 《Journal of Thermal Analysis and Calorimetry》2021,146(3):1323-1333
Journal of Thermal Analysis and Calorimetry - The inclusion of solid nano-structures in the liquid changes its rheology and hence its thermal performance. This article considers the impact of... 相似文献
189.
Ahangar Zonouzi Sajjad Khodabandeh Rahmatollah Safarzadeh Habibollah Aminfar Habib Mohammadpourfard Mousa Ghanbarpour Morteza 《Journal of Thermal Analysis and Calorimetry》2020,140(6):2805-2816
Journal of Thermal Analysis and Calorimetry - In this study, the subcooled boiling heat transfer of a Fe3O4/water magnetic nanofluid flowing through a vertical tube has been investigated... 相似文献
190.
Design and synthesis of novel thiourea metal complexes with controllable antibacterial properties
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A new bidentate O,S donor thiourea ligand (L1), namely N‐(2‐hydroxyethyl)‐N′‐2‐chlorobenzoylthiourea, and its oxazolidine derivative (L2) were synthesized. Derivative L2 was used for the preparation of Ni(L2)2 and Cu(L2)2 complexes. The compounds were investigated using X‐ray crystallography and Fourier transform infrared, 1H NMR and UV–visible spectroscopies. Single‐crystal X‐ray analysis showed strong hydrogen bonding interactions between carbonyl oxygen and N(10) ─ H in the L1 ligand. In addition, the antibacterial activities of these compounds were evaluated against Gram‐positive and Gram‐negative bacteria, measured using the colony count method. The Cu(L2)2 complex exhibited a significant antibacterial activity while the activity of the other compounds was much lower. Finally, the relationship between the structure and antibacterial properties of these compounds was investigated using highest occupied and lowest unoccupied molecular orbital energies calculated by density functional theory method based on the 6‐31G*/LANL2DZ basis set. 相似文献