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11.
Khalid Mohammed Khan Muhammad Taha Fazal Rahim Waqas Jamil Shahnaz Perveen Muhammad Iqbal Choudhary 《Journal of the Iranian Chemical Society》2012,9(1):81-83
Treatment of indole with substituted aldehyde in the presence of equimolar amount of sodium bromate and sodium hydrogen sulfite mixture in water yielded corresponding substituted bis(indolyl)methanes in good yields. This provides a facile and environmentally friendly method towards the synthesis of an important class of organic compounds. 相似文献
12.
Uzma Yasmeen Fazal Haq Mehwish Kiran Arshad Farid Naveed Ullah Tariq Aziz Muhammad Haroon Sahid Mehmood Muhammad Muzammal Shakira Ghazanfar Majid Alhomrani Abdulhakeem S. Alamri Syed Mohammed Basheeruddin Asdaq Saleh A. Alghamdi Irfan Ullah 《Molecules (Basel, Switzerland)》2022,27(18)
In this research, a new biodegradable and eco-friendly adsorbent, starch-grafted polymethyl methacrylate (St-g-PMMA) was synthesized. The St-g-PMMA was synthesized by a free radical polymerization reaction in which methyl methacrylate (MMA) was grafted onto a starch polymer chain. The reaction was performed in water in the presence of a potassium persulfate (KPS) initiator. The structure and different properties of the St-g-PMMA was explored by FT-IR, 1H NMR, TGA, SEM and XRD. After characterization, the St-g-PMMA was used for the removal of MB dye. Different adsorption parameters, such as effect of adsorbent dose, effect of pH, effect of initial concentration of dye solution, effect of contact time and comparative adsorption study were investigated. The St-g-PMMA showed a maximum removal percentage (R%) of 97% towards MB. The other parameters, such as the isothermal and kinetic models, were fitted to the experimental data. The results showed that the Langmuir adsorption and pseudo second order kinetic models were best fitted to experimental data with a regression coefficient of R2 = 0.93 and 0.99, respectively. 相似文献
13.
Sundas Mumtaz Shahid Iqbal Mazloom Shah Rafaqat Hussain Fazal Rahim Wajid Rehman Shoaib Khan Obaid-ur-Rahman Abid Liaqat Rasheed Ayed A. Dera Hanan A. Al-ghulikah Sana Kehili Eslam B. Elkaeed Hamad Alrbyawi Mohammed Issa Alahmdi 《Molecules (Basel, Switzerland)》2022,27(19)
Twenty-four analogs based on triazinoindole bearing benzimidazole/benzoxazole moieties (1–25) were synthesized. Utilizing a variety of spectroscopic methods, including 1H-, 13C-NMR, and HREI-MS, the newly afforded compounds (1–25) were analyzed. The synthesized analogs were tested against urease enzyme (in vitro) as compared to the standard thiourea drug. All triazinoindole-based benzimidazole/benzoxazole analogs (1–25) exhibited moderate to excellent inhibition profiles, having IC50 values of 0.20 ± 0.01 to 36.20 ± 0.70 μM when evaluated under the positive control of thiourea as a standard drug. To better understand the structure–activity relationship, the synthesized compounds were split into two groups, “A” and “B.” Among category “A” analogs, analogs 8 (bearing tri-hydroxy substitutions at the 2,4,6-position of aryl ring C) and 5 (bearing di-hydroxy substitutions at the 3,4-position of aryl ring C) emerged as the most potent inhibitors of urease enzyme and displayed many times more potency than a standard thiourea drug. Besides that, analog 22 (which holds di-hydroxy substitutions at the 2,3-position of the aryl ring) and analog 23 (bearing ortho-fluoro substitution) showed ten-fold-enhanced inhibitory potential compared to standard thiourea among category “B” analogs. Molecular docking studies on the active analogs of each category were performed; the results obtained revealed that the presence of hydroxy and fluoro-substitutions on different positions of aryl ring C play a pivotal role in binding interactions with the active site of the targeted urease enzyme. 相似文献
14.
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
15.
Pyrolysis has the potential of transforming used tyres into useful recyclable products. Pyrolytic carbon black is one of the most important products of tyre pyrolysis. Waste tyres were pyrolysed at 450 °C in a batch reactor under atmospheric pressure. The recovered pyrolytic carbon black residues were studied to investigate their characteristics for use as a possible adsorbent. EDX elemental analysis and surface area determinations were used to investigate the distinctive features of pyrolytic carbon black. Due to various inorganic additives of the original tyre that contaminated the carbon black obtained, it was treated with acid for demineralization. The demineralized carbon black was activated at 900 °C in a furnace. It was observed that acid treatment and activation increased the surface areas and decreased the concentration of contaminants. Furthermore, adsorption characteristics of methylene blue on acid‐treated and activated carbon black (prepared via acid treatment) were compared with those of commercial activated carbon in liquid phase adsorption. It was found that adsorption capacity of methylene blue on acid‐treated activated carbon black was greater. 相似文献
16.
17.
Kh.S.Karimov Muhammad Tariq Saeed Chani Fazal Ahmad Khalid Adam Khan Rahim Khan 《中国物理 B》2012,(1):329-333
In this paper,we present the design,the fabrication,and the experimental results of carbon nanotube (CNT) and Cu 2 O composite based pressure sensors.The pressed tablets of the CNT-Cu 2 O composite are fabricated at a pressure of 353 MPa.The diameters of the multiwalled nanotubes (MWNTs) are between 10 nm and 30 nm.The sizes of the Cu 2 O micro particles are in the range of 3-4 μm.The average diameter and the average thickness of the pressed tablets are 10 mm and 4.0 mm,respectively.In order to make low resistance electric contacts,the two sides of the pressed tablet are covered by silver pastes.The direct current resistance of the pressure sensor decreases by 3.3 times as the pressure increases up to 37 kN/m 2.The simulation result of the resistance-pressure relationship is in good agreement with the experimental result within a variation of ±2%. 相似文献
18.
Ikram Hussain Atif Fazal Khurshid Alam Anwar Hossaen 《Polymer Degradation and Stability》2010,95(12):2289-2299
Catalyst creates new grades of polyethylenes while their degradation phenomena determine the resulting application profiles. The resins and the end-products eventually contain residual catalysts. Therefore, the effects of the following two residual catalysts—one Ziegler-Natta [PQ Silica/Bu2Mg/tBuCl/TiCl4], and the other metallocene [PQ Silica/MAO/(nBuCp)2ZrCl2]—on the UV-induced degradation of the resulting unstabilized ethylene homopolymer films were studied. The MetCat HomoPE film was found to be more susceptible to UV-induced degradation degradation than the Z-N HomoPE one despite the residual Zr level was 1/15th of the Ti content. Therefore, the zirconocene residual catalyst better (i) facilitated the UV-initiated reaction, and (ii) decreased the activation energy required for the decomposition of the resulting hydroperoxide. These findings were explained from the differences in (i) electronic configuration and atomic radius, and (ii) surface chemistry and solid-state electronic environment of these catalyst systems. In both films, Tpm and Tpc did not significantly vary with the exposure time. The change of % crystallinity showed to be irregular and disturbed. As a function of carbonyl index, Tpm and Tpc,varied in a similar fashion in the MetCat HomoPE film. However, they significantly differed for the Z-N HomoPE film. Here, Tpm did not appreciably change whereas Tpc initially increased very mildly; then it did not essentially differ. 相似文献
19.
Khasan Sanginovich Karimov Muhammad Tariq Saeed Chani Fazal Ahmad KhalidAdam Khan 《Physica E: Low-dimensional Systems and Nanostructures》2012,44(4):778-781
This paper presents the design, fabrication and experimental results of carbon nanotubes-cuprous oxide (CNTs-Cu2O) composite based strain sensors. The press-tablets were fabricated from the blend of CNTs (25 wt%) and Cu2O (75 wt%) at a pressure of 353 MPa. The diameter of multiwalled carbon nanotubes (MWCNTs) varied between 10 and 30 nm. The sizes of Cu2O micro-particles were in the range of 3-4 μm. The thickness of the press-tablets was 1 mm. The samples were installed on the polymer elastic beam by glue. The electric contacts to the samples were made by silver paste. The inter-electrodes distance (length) and diameter of the surface-type samples were in the range of 6-8 mm and 10 mm, respectively. The DC resistance of the strain sensors increases under tension and decreases under compression, while the average strain sensitivities are in the range of 44-46 and 24-28 for tension and compression, respectively. The simulation is in good agreement with the experimental results. 相似文献
20.
Gábor Blaskó Natesan Murugesan S.Fazal Hussain Robert D. Minard Maurice Shamma Bilge Şener Mekin Tanker 《Tetrahedron letters》1981,22(33):3135-3138
Fumarofine is not a spirobenzylisoquinoline. Rather, it is the first know reduced indenobensazepine alkaloid, and possesses the cis B/C fused structure . Rearrangement of synthetic spirobensylisoquinoline using methanesulfonyl chloride furnished indenobensazepine . Osmium tetroxide oxidation of gave cis-glysol . O-Methylfumarofine () was then obtained through pyridinium chlorochromate oxidation of . 相似文献