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材料科学与工程（中英文版） 2011年第4期5卷 363-377页

作者： zakir m.o. rzayev A. Emur Soylemez Burhan Davarcioglu Emir B. Denktas Institute of Science ＆ Engineering Division of Nanoscienee and Nanomedieine Hacettepe University Beytepe Ankara 06800Turkey Department of Physics Faculty of Science ＆ Art Aksaray University Aksaray 68100 Turkey

Functional copolymer/organo-silicate [octadecyl amine (oDA) surface modified montmorillonite (mmT)] layered nanocom.o.ites have been synthesized by interlamellar complex-radical copolymerization of preintercalated complexes of maleic anhydride (mA)... oDA-mmT and itaconic acid (IA)... oDA-mmT as ‘nano-reactors’ with n-butyl methacrylate (BmA) as an internal plasticization comonomer in the presence of radical initiator. It was demonstrated that intercalation and exfoliation in situ processes are accompatied by physical (H-bonding) and chemical (amidization/imidization) interfacial interactions of monomers with oDA-mmT which are responsible for the formation of nanostructural hybrid architectures. The synthesized copolymers and their nanocom.o.ites were investigated by X-ray diffraction, TGA-DSC, SEm and TEm methods. It was found that nanocom.o.ites’ crystallinity, thermal properties and morphology strongly depended on the force of interfacial monomer... oDA-mmT complex-formation and the amount of flexible n-butyl ester linkages. An increase in both of these parameters leads to enhanced intercalation and exfoliation in situ processes of copolymer chains and the formation of hybrid nanocom.o.ites.

关键词：纳米复合材料有机蒙脱土十八烷基胺共聚合成共聚物衣康酸马来酰胺甲基丙烯酸丁酯

Tribological properties of Al-GNP com.o.ites at elevated temperature

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Friction 2024年第5期12卷 1028-1041页

作者： Sunil PoUDEL Rizwan BAJWA Yongde XIA zakir KHAN Yi ZHANG Yanqiu ZHU College of Engineering Mathematics and Physical SciencesUniversity of ExeterExeterEX44QFUK European Technical Centre Daido Metal Co.Ltd.Iliminster SomersetTA199PHUK

Lighter and more powerful next generation vehicles and other rotary machinery demand bearings to operate in harsher conditions for higher efficiency,and the continuous development of advanced low-wear and friction materials is thus becoming even more im.o.tant to meet these *** aluminium com.o.ites reinforced with high performance lubricate phases such as graphene nanoplatelets(GNPs)are very promising and have been vigorously *** maintaining a low coefficient of friction(CoF)and offering great strength against wear due to their self-lubricating capability,the solid lubricant like GNPs protect the bearing surface from wear damage and prevent change in metallurgical properties during temperature *** paper first studies the high-temperature tribological performance of aluminium matrix com.o.ites reinforced with GNP,consolidated via powder metallurgy,then elucidates their tribological *** report that the best tribological performance is achieved by the com.o.ite containing 2.0 wt%GNP,with an extraordinarily low CoF of 0.09 and a specific wear rate of 3.5×10^(−2)mm^(3)·N^(−1)·m^(−1),which represent 75%and 40%reduction respectively,against the plain aluminium consolidated under identical *** in-track and out-of-track Raman analysis have confirmed the role of GNPs in creating a tribofilm.o. the counterpart surface which contributed to the excellent performance.

关键词： nanocom.o.ite graphene nanoplatelet(GNP) tribology powder metallurgy

microalgae cultivation in photobioreactors: sustainable solutions for a greener future

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Green Chemical Engineering 2024年第4期5卷 418-439页

作者： Shaikh Abdur Razzak Khairul Bahar K.m.o.jedul Islam Abdul Khaleel Haniffa mohammed omar Faruque S.m.zakir Hossain mohammad m.Hossain Chemical Engineering Department King Fahd University of Petroleum and Minerals Center for Refining and Advanced Chemicals King Fahd University of Petroleum & Minerals Department of Chemical Engineering University of Bahrain

microalgae cultivation in photobioreactors（PBRs） has emerged as a promising and sustainable approach to address various environmental and energy challenges, offering a multitude of benefits across diverse *** developments in microalgae cultivation in photobioreactors have contributed substantially to the development and optimization of sustainable bioprocesses. This review presents a comprehensive analysis of recent innovations and breakthroughs in the field of microalgae cultivation, with a specific focus on their application in photobioreactors, aimed at paving the way for a greener future. This study in-depth examines the advantages of microalgae cultivation in photobioreactors, concentrating on its effectiveness in wastewater treatment, Co2bioremediation, and the production of biofuels and high-value products. The review evaluates the effects of light,solar irradiation, temperature, nitrogen and phosphorus concentrations in culture media, Co2concentrations, and pH on microalgae growth performance, including specific growth and biomass productivity. The study also examines open systems like unstirred ponds, raceway ponds, and circular ponds and closed systems like horizontal tubular, vertical bubble-column, airlift, flat panel, and plastic-bag photobioreactors, comparing their pros and cons. To optimize microalgae cultivation, key factors in photobioreactor design, including photosynthetic efficiencies, light/dark（L/D） cycles, Co2concentrations, mass transfer, hydrodynamics behavior, and p H, are extensively investigated. In addition, the review outlines recent developments in large-scale photobioreactors and highlights the challenges and opportunities associated with photobioreactor scale-up and design parameter optimization, including genetic engineering and economic feasibility. This article is a vital resource for researchers, engineers, and industry professionals seeking sustainable bioprocesses and the application of microalgae-based technol

关键词： microalgae biomass Co 2 biofixation Wastewater treatment Biofuel Photobioreactors

Predicting the Stitch Density of Finished Fabrics Using Weft Blended Grey Knit Fabrics

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Journal of Textile Science and Technology 2024年第3期10卷 51-63页

作者： Kazi md. Elias mohammad obaidur Rahman H. m. zakir Hossain Department of Physics Jahangirnagar University Savar Bangladesh Jute Textile Wing Bangladesh Jute Research Institute Dhaka Bangladesh

Stitch density is one of the critical quality parameters of knit fabrics. This parameter is closely related to other physical quality parameters like fabric weight, fabric tightness factor, fiber types, blend ratio, yarn diameter and linear density, and fabric structure. Selecting stitch density (wales per inch, course per inch) is essential to getting the appropriate fabric weight and desired quality. Usually, no rules or assumptions exist to get the desired stitch density in the finished fabric stage. Fifteen types of blended knit fabrics were prepared to conduct the study. The varying percentages of cotton, polyester, and elastane are incorporated in the blends. Regression analysis and regression ANoVA tests were done to predict the stitch density of finished fabrics. A suitable regression equation is established to get the desired results. The study also found that the stitch density value in the finished stage fabric decreases by approximately 15% compared to the stitch density in the grey fabric stage. This study will help the fabric manufacturers get the finished fabric stitch density in advance by utilizing the grey fabric stitch density data set. The author expects this research to benefit the knitting and dyeing industry, new researchers, and advanced researchers.

关键词： Wales per Inch Course per Inch Stitch Density Blended Knit Fabric

Functional Copolymer/organo-mmT ***,morphology and Thermal Behavior of Poly(maleic anhydride-alt-acrylamide)-organo-mmT Clays Nanohybrids

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Engineering（科研） 2011年第1期3卷 73-82页

作者： zakir m.o.rzayev Burcu Senol Ernur A.Soylemez Department of Chemical Engineering Faculty of EngineeringDivision of Nanoscience&Nanomedicine Hacettepe UniversityAnkaraTurkey

Functional copolymer–clay hybrids were synthesized by radical-initiated intercalative copolymerization of maleic acid (mA) and acrylamide (AAm) with 2,2’-azobis (2-methylpropionamidine) dihydrochloride as a water-soluble ionizable radical initiator in the presence of reactive (octadecyl amine (oDA)-mmT) and non-reactive (dimethyldodecyl am.o.ium (DmDA)-mmT) organoclays at 50oC in aqueous medium under nitrogen atmosphere. The monomers was dissolved in aqueous medium, as well as both used clay particles were easily dissolved and dispersed with partially swollen in deionized water, respectively. Structure, thermal behavior and morphology of the synthesized nanocom.o.ites were investigated by FTIR, XRD, DSC-TGA, SEm and TEm analysis methods, respectively. It was demonstrated that intercalative copolymerization proceed via ion exchange between organoclays and carboxylic groups of monomers/polymers which essentially improved interfacial interaction of polymer matrix and clay layers through strong H-bonding. In case of intercalative copolymerization in the presence of oDA-mmT clay, similar improvement was provided by in situ hydrogen-bonding and amidolysis of carboxylic/anhydride groups from copolymer chains with primary amine group of oDA-mmT. The nanocom.o.ites exhibit higher intercalation/exfoliation degree of copolymer chains, improved thermal properties and fine dispersed morphology.

关键词： Functional Copolymer organoclays Nanohybrid Com.o.ites Thermal Behavior morphology

Local site effects evaluation by surface wave and H/V survey methods in Senirkent(Isparta)region,southwestern Turkey

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 321-333页

作者： mehmet zakir Kanbur Ali Silahtar Gokhan Aktan Suleyman Demirel University Engineering FacultyDepartment of Geophysical EngineeringIspartaTurkey

This study aimed to investigate the site characterization of the Senirkent Basin(Isparta)by using the microtremor(H/V)and surface wave analysis(Remi)*** district,which is located on the foothill of the Kap?mountain,are prone to seismic and landslide *** the last landslip disaster(1995),the city has continued to develop on the alluvial *** microtremor data collected at 41 stations were *** predominant frequency and the amplification of the soil were found to be in the range of 1.8–6.6 Hz and 0.8–6.8,*** are 4.0-6.8 Hz and 1-2.5 around the slope of the Kap?mountain and 0.8-3.6 Hz and 3.0-6.6 at alluvium deposits of the *** Remi data collected along 41 profiles were analyzed to obtain a Vs30 *** soil classifications were done by using Vs30 values according to NEHRP soil classification *** results showed that the southern area of the study had better soil conditions with Vs30 between 360-1160 m/s and soil class between C and *** alluvium deposits on the north are relatively low with Vs30 in the range of 260-360 m/s and soil class D.

关键词： site characterization microtremor surface waves Vs30 Z1.0

Bioengineering functional copolymers. XII. Interaction of boron-containing and PEo branched derivatives of poly(mA-alt-mVE) with HeLa cells

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Health 2010年第1期2卷 51-61页

作者： mustafa Türk zakir m. o. rzayev Gülcihan Kurucu 不详

Novel boron-containing bioengineering copoly- mer and its α-hydoxy-ω-methoxy-poly(ethy- lene oxide (PEo) macrobranched derivatives were synthesized by (1) partially amidolysis of poly(maleic anhydride-alt-methyl vinyl ether) w?th ethanolamine ester of diphenylboronic acid and (2) esterification of synthesized B-con- taining copolymers with PEo. They had a com- bination of hydrophilic/hydrophobic linkages, free carboxylic groups, positive charges and an ionized organoboron linkage as antitumor sites, along with an ability to interact with HeLa cells. The structure, com.o.ition and properties (cy- totoxicity and antitumor activity) of synthe- sized copolymers were investigated. In vitro cytotoxicity results, obtained by the fluore scence microscopy measurements indicate that unlike the virgin copolymer, boron-containing and PEo macrobranched derivatives exhibit higher antitumor activity. It was found that organoboron copolymer exhibits the most apo- ptotic and necrotic effects against HeLa cells whereas a minor effect relative to cancer cells was observed on L929 Fibroblast cells.

关键词： Synthesis organoboron Copolymers Structure-Property Relations Cytotoxicity Antitumor Activity Apoptotic Effect

Bioengineering Functional Copolymers. XVII. Interaction of organoboron Amide-Ester Branched Derivatives of Poly(Acrylic Acid) with Cancer Cells

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Journal of Cancer Therapy 2011年第2期2卷 266-275页

作者： mustafa Türk Gülten Kahraman Sevda A. Khalilova zakir m. o. rzayev Serpil oguztüzün Institute of Science & Engineering Division of Nanoscience and Nanomedicine Hacettepe University Ankara Turkey.

Novel bioengineering functional organoboron polymers were synthesized by 1) amidolysis of poly(acrcylic acid) (PAA) with 2-aminoethyldiphenyl borinate (2-AEPB), 2) esterification of organoboron PAA polymer (PAA-B) with a-hydroxy-methoxypoly(ethylene oxide) (PEo) as a compatibilizer and 3) conjugation of organoboron PEo branches (PAA-B-PEo) with folic acid (FA) as a targeting agent. Structure and com.o.ition of the synthesized polymers were characterized by FTIR-ATR and 1H (13C) NmR spectroscopy, chemical and physical analysis methods. Anti-tumor activity of organoboron functional polymer and its complex with FA (PAA-B-PEo-F) against cancer and normal cells were evaluated by using different biochemical methods such as cytotoxicity, statistical, apoptotic and necrotic cell indexes, double staining and caspase-3 immune staining, light and fluorescence inverted microscope analyses. It was found that citotoxicity and apoptotic/necrotic effects of polymers significantly depend on the structure and com.o.ition of studied polymers, and increase the following raw: PAA o o-F. Among them, PAA-B-PEo-F complex at 400 mg mL–1 concentration as a therapeutic drug exhibits minimal toxicity toward the nor-mal cells, but influential for HeLa cancer cells.

关键词： Synthesis Amidolysis organoboron Polymers Conjugation Citotoxicity Apoptotic and Necrotic Effects

A decline in snow cover area of Passu and Ghulkin valleys between 1995 and 2022

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Journal of mountain Science 2023年第12期20卷 3542-3551页

作者： Imran HUSSAIN mumtaz ALI Sher mUHAmmAD Wajid HASSAN Salar ALI zakir HUSSAIN Syed Hammad ALI Shaukat ALI muhammad Younis KHAN Department of Environmental Sciences University of BaltistanSkardu 16100Pakistan micromaps IT and GIS Consultancy LLC 26135UAE International Centers for Integrated mountain Development(ICImoD) G.P.O.Box 3226KathmanduNepal Institute of mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Glacier monitoring Research Centre(GmRC) Water and Power Development Authority(WAPDA)Lahore 54000Pakistan SickKids Centre for Global Child Health The Hospital for Sick ChildrenTorontoOntario M5G 2L3Canada Global Change Impact Studies Center(GCISC) Islamabad 44000Pakistan Departments of Earth Sciences College of ScienceSultan Qaboos UniversityMuscat 123Oman National Centers of Excellence in Geology(NCEG) University of PeshawarPeshawar 25130Pakistan

The global cryosphere is experiencing accelerated melting due to climate ***,the Karakoram anomaly is under discussion with a debate about the possibility that the anomaly may have recently *** study aims to evaluate the up-to-date changes in snow cover in the western Karakoram *** observed the snow cover changes in Passu and Ghulkin valleys in the Hunza River basin(HRB)of the Karakoram through multitem.o.al Landsat satellite data between 1995 and *** found a significant reduction in snow cover in these valleys,with an average reduction rate of 0.42 km~2/yr,resulting in a total reduction of~11.46 km~2 between 1995 and *** reduction in snow cover is consistent with the mass loss of glaciers in the Karakoram region in recent *** decline in snow cover in these valleys is also consistent with the meteorological *** temperature in summer(June)has significantly increased whereas the precipitation in the accumulation season(march)has *** rapid changes suggest that it is crucially im.o.tant to monitor the snow cover on a regular basis to support downstream management of snowmelt *** addition,there is a need of planning for mitigation and adaptation strategies for snow-related hazards.

关键词： Cryosphere Snow covers area Climate change Karakoram

Estimation of Vitamins B-Complex (B2, B3, B5and B6) of Some Leafy Vegetables Indigenous to Bangladesh by HPLC method

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Journal of Analytical Sciences, methods and Instrumentation 2013年第3期3卷 24-29页

作者： md. Nazmul Hasan m. Akhtaruzzaman md. zakir Sultan Centre for Advanced Research in Sciences Uni- versity of Dhaka Dhaka Bangladesh Institute of Nutrition and Food Science University of Dhaka Dhaka Bangladesh

The current experiment was conducted for the simultaneous determination of several water-soluble vitamins like ribo- flavin (vitamin B2), niacin (vitamin B3), pantothenic acid (vitamin B5) and pyridoxine (vitamin B6) in five highly con- sumed local leafy vegetables named as bottle gourd leaves (Lagenaria vulgaris) (local name Lau shak), green amaranth leaves (Amaranthus viridis) (local name Data shak), red amaranth leaves (Amaranthus gangeticuss) (local name Lal shak), Indian spinach (Basella alba) (local name Pui shak) and bitter gourd leaves (momordica charantia) (local name Korola shak). The analyses were performed by HPLC using an analytical reversed phase C-18 (oDS column, 250 × 4.6 mm, 5 μm, Phenomenex, Inc.) column with the mobile phase consisting of a mixture of buffer (hexane sulphonic acid sodium, potassium dihydrogen phosphate and triethylamine, pH 3.0) and methanol in the ratio of 96:4 (v/v) at a flow rate of 1 mL/min with UV detection at 210 nm. The retention times for the vitamins were obtained as 3.61 min, 6.37 min, 9.51 min and 11.51 min for Vitamins B2, B3, B5 and B6, respectively. These obtained values of the vitamins were compared with the values available in published literatures of Deshio Khaddar Pustiman (DKPm), Indian food value (IFV) and United States Department of Agriculture (USDA).

关键词： HPLC Analysis Vitamin B2 Vitamin B3 Vitamin B5 Vitamin B6 Leafy Vegetables