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A facile synthesis of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl) acetamidines

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Chinese Chemical Letters 2010年第8期21卷 905-910页

作者： Rasool Khan mohammad Arfan Javeed mahmood Shazia Anjum m.iqbal Choudhary Department of Chemistry Abdul Wali Khan UniversityMardan-23200NWFPPakistan Institute of Chemical Sciences University of PeshawarPeshawar-25120Pakistan University of Saskatchewan Department of ChemistrySaskatoon S7N5C9Canada HEJRIC International Center for Chemical and Biological SciencesUniversity of KarachiKarachi-75270Pakistan

A series of novel unsymmetrical N-（4-oxo-2-phenyl-3（4H）-quinazolinoyl）-N-（aryl） acetamidines was synthesized by reacting ethyl（1H）-N-（4-oxo-2-phenylquinazolin-3（4H）-y1）ethanimidoate（2） and suitable reactive aromatic ***＇ determination of the synthesized compounds was carried out using spectroscopic techniques including IR,~1H NmR,and mass spectrometry. Structural effects on reactivity were also studied.

关键词： 3-Amino-2-phenyl-4(3H)-quinazolinone Triethylorthoacetate Unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl) acetamidines

FIXED POINT THEOREmS AND BEST APPROXImATION IN CONVEX mETRIC SPACES

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Analysis in Theory and Applications 1992年第4期8卷 97-105页

作者： I.Beg N.Shahzad m.iqbal Quaid-i-Azam University Pakistan

Results regarding best approximation and best Simultaneous approximation on convex metric spaces are *** of fixed points for an ultimately nonexpansive semigroup of mappings is also shown.

关键词： CIG FIXED POINT THEOREmS AND BEST APPROXImATION IN CONVEX mETRIC SPACES

Defensive Role of Plant Hormones in Advancing Abiotic Stress-Resistant Rice Plants

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Rice science 2023年第1期30卷 15-35页

作者： m.iqbal R.KHAN Sarika KUmARI Faroza NAZIR Risheek Rahul KHANNA Ravi GUPTA Himanshu CHHILLAR Department of Botany Jamia HamdardNew Delhi 110062India College of General Education Kookmin UniversitySeoul 136702South Korea

Consistent climatic perturbations have increased global environmental concerns, especially the impacts of abiotic stresses on crop productivity. Rice is a staple food crop for the majority of the world’s population. Abiotic stresses, including salt, drought, heat, cold and heavy metals, are potential inhibitors of rice growth and yield. Abiotic stresses elicit various acclimation responses that facilitate in stress mitigation. Plant hormones play an important role in mediating the growth and development of rice plants under optimal and stressful environments by activating a multitude of signalling cascades to elicit the rice plant’s adaptive responses. The current review describes the role of plant hormone-mediated abiotic stress tolerance in rice, potential crosstalk between plant hormones involved in rice abiotic stress tolerance and significant advancements in biotechnological initiatives including genetic engineering approach to provide a step forward in making rice resistance to abiotic stress.

关键词： abiotic stress genetic engineering plant hormone rice transcription factor tolerance

New antiglycation and enzyme inhibitors from Parmotrema cooperi

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Science China Chemistry 2011年第12期54卷 1926-1931页

作者： m.iqbal CHOUDHARY meher ALI Atia-tul-WAHAB Ajmal KHAN Saima RASHEED Sajan Lal SHYAULA(Shrestha) Atta-ur-RAHmAN H.E.J.Research Institute of Chemistry International Center for Chemical and Biological SciencesUniversity of Karachi Dr.Panjwani Center for molecular medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of Karachi Department of Chemistry College of ScienceKing Saud University Nepal Academy of Science and Technology

Lichens are unique individuals which have been widely used in traditional medicines. This study was focused on the bioassayguided phytochemical investigation, and bioactivity evaluation on a lichens species, Parmotrema cooperi. This first bioassaydirected chemical study on P. cooperi has led to the isolation of ethyl heamatomate （1）, atraric acid （2）, ethyl orsellinate （3）, orsellinic acid （4）, lecanoric acid （5）, gyrophoric acid （6）, and licanorin （7）. The structures of 1-7 were mainly elucidated from spectroscopic methods including 1D, and 2D NmR spectroscopy, and mass spectrometry. These compounds were evaluated for their antiglycation, urease, a-chymotrypsin, and β-glucoronidase inhibitory activities. Few of the phenolic compounds showed significant, while most of them showed good inhibition of protein glycation, and urease activities.

关键词： lichen Parmotrema cooped ethyl heamatomate atraric acid urease inhibition antiglycation

Ageing Effect on Hardness and microstructure of Al-Zn-mg Alloys

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Journal of materials Science & Technology 2000年第3期16卷 319-322页

作者： m.iqbal, m.A.Shaikh, m.Ahmad and K.A.Shoaib (Nuclear Physics Division, Pakistan Institute of Nuclear Science and Technology P.O.Nilore, Islamabad, Pakistan) Nuclear Physics Division Pakistan Institute of Nuclear Science and Technology Islamabad P.O.Nilore Pakistan

Experimental results of the investigation on the hardness of two Al-Zn-mg alloys [Al-10.0 Zn-4.0 mg and Al-8.5 Zn-3.0 mg (wt pct)] aged in the temperature range 60～310℃ for different intervals of time from 1/4 h to 168 h are presented. Both the alloys were found to show identical behaviour of hardness with ageing time. Alloy with higher Zn and mg content had higher hardness than the alloy with lower solute content. There were three ranges of temperature in which different types of precipitates formed and affected the hardness. Some of the grain boundaries were found to migrate and precipitate free zone has been observed.

关键词： Zn Ageing Effect on Hardness and microstructure of Al-Zn-mg Alloys Al

Anthelmintic, antimicrobial, antioxidant and cytotoxic activity of Caltha palustris var. alba Kashmir, India

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Chinese Journal of Natural medicines 2014年第8期12卷 567-572页

作者： Sofi mubashir mohd Yousuf Dar Bashir A.Lone m.iqbal Zargar Wajaht A.Shah Department of Chemistry University of Kashmir Centre of Research for Development University of Kashmir Department of Pharmaceutical Sciences University of Kashmir

The methanolic extract obtained from the root portion of Caltha palustris var. alba was evaluated for its anthelmintic efficacy against gastrointestinal nematodes of sheep under both in vitro and in vivo conditions using worm motility inhibition(WmI) assay and fecal egg count reduction(FECR) assay, respectively. The extract was subjected to antimicrobial activity using agar-well diffusion method against different bacterial strains. In addition the extract was evaluated for cytotoxic and antioxidant activity against cultured THP-1(Leukemia), A-549(Lung), HCT-15(Colon), Cervix(HeLa) and PC-3(Prostrate) cell lines by SRB and DPPH radical scavenging assays. The extract used resulted in mean %WmI of 94.44%, as observed when the worms were put in lukewarm buffer for 30 min after exposure to different treatments. The mean mortality index of the sample was 0.95. The lethal concentration(LC50) was 0.11 mg·mL-1. Cell lines were exposed to concentration of 100 μg·mL-1 of extract for 48 h, which reduced the viability of these cell lines. The same plant extract also showed 55.58% DPPH radical scavenging activity.

关键词： Caltha palustris var.alba Anthelmintic activity(in vivo and in vitro) Antimicrobial activity Cytotoxic activity Radical scavenging activity

Parmotrema cooperi中的新型抗醣化物质和酶抑制剂

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中国科学：化学 2012年第1期42卷 97-98页

作者： m.iqbal CHOUDHARY meher ALI Atia-tul-WAHAB Ajmal KHAN Saima Rasheed Sajan Lal SHYAULA(Shrestha) Atta-ur-RAHmAN 陈洁 H.E.J.Research Institute of Chemistry International Center for Chemical and Biological SciencesUniversity of Karachi Panjwani Center for molecular medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of Karachi Department of Chemistry College of ScienceKing Saud University Nepal Academy of Science and Technology 厦门大学化学化工学院

地衣是被广泛用于传统药物中的独特个体.本文对一类地衣,Parmotrema cooperi,进行了生物测定引导的植物化学研究和生物活性评价.对该类地衣的首次生物测定引导的化学研究分离出了化合物ethyl heamatomate(1),atraric acid(2),ethyl orse... 详细信息

地衣是被广泛用于传统药物中的独特个体.本文对一类地衣,Parmotrema cooperi,进行了生物测定引导的植物化学研究和生物活性评价.对该类地衣的首次生物测定引导的化学研究分离出了化合物ethyl heamatomate(1),atraric acid(2),ethyl orsellinate(3),orsellinic acid(4),lecanoric acid(5),gyrophoric acid(6)以及licanorin(7).化合物1～7的结构主要通过一维、二维核磁共振谱和质谱等谱学方法判定.对这些化合物还进行了抗醣化活性以及尿素酶、α-胰凝乳蛋白酶、β-葡萄糖醛酸苷酶抑制活性的评价.这些苯酚化合物没有显示特别好的活性,但其中大部分对蛋白质醣化和尿素酶活性具有较好的抑制作用.

关键词：地衣 Parmotrema cooperi 尿素酶抑制作用抗醣化作用

Failure pattern in ceramic metallic target under ballistic impact

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Defence Technology（防务技术） 2024年第10期40卷 173-190页

作者： m.A.iqbal m.K.Khan Department of Civil Engineering Indian Institute of Technology RoorkeeRoorkee 247667India Department of Civil Engineering Aligarh Muslim UniversityAligarh202002India

The ballistic resistance and failure pattern of a bi-layer alumina 99.5%-aluminium alloy 1100-H12 target against steel 4340 ogival nosed projectile has been explored in the present experimental cum numerical *** the experimental investigation,damage induced in the ceramic layer has been quantified in terms of number of cracks developed and failure zone *** resultant damage in the backing layer has been studied with variation in the bulge and perforation hole in the backing layer with the varying incidence *** discussion of the experimental results has been further followed by three dimensional finite element computations using ABAQUS/Explicit finite code to investigate the behaviour of different types of bi-layer targets under multi-hit projectile *** JH-2 constitutive model has been used to reproduce the behaviour of alumina 99.5%and JC constitutive model has been used for steel 4340 and aluminium alloy *** total energy dissipation has been noted to be of lesser magnitude in case of sub-sequential impact in comparison to simultaneous impact of two *** distance between the impact points of two projectiles also effected the ballistic resistance of bi-layer *** ballistic resistance of single tile ceramic front layer and four tile ceramic of equivalent area found to be dependent upon the boundary conditions provided to the target.

关键词： Ballistic resistance Bi-layer target Ceramic metal armour multi-hit impact Finite element modelling

Soliton formation in electron-temperature-gradient-driven magnetoplasma

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Plasma Science and Technology 2018年第2期20卷 82-86页

作者： m Yaqub KHAN Javed iqbal Department of mathematics Riphah International University

Electron-temperature-gradient（ETG）-driven solitons are studied in a *** derive the linear dispersion relation and an admitted solitary wave solution Korteweg–de Vries-typeequation（Kd V）for the ETG mode in the nonlinear regime by using the Braginskii model and a *** is found that the ETG mode supports only rarefactive *** is also observed that the ratio of electron-to-ion temperature t=T T,e ithe ratio of gradient scale lengths h=L L,（en） Tand the magnetic field B affect both the amplitude and width of a *** is found that the soliton profile changes with variation in these *** apply the homotopy perturbation method to the derived Kd V *** is found this method is computationally attractive and the results are very *** work may be useful to study the low electrostatic modes in inhomogeneous electron–ion plasma with density and *** illustration,the model has been applied to tokamak plasma.

关键词： ETG mode KdV equation HPm