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Petrogenesis and Tectonic Implications of Peralkaline A-Type Granites and Syenites from the Suizhou-Zaoyang Region,Central China

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Journal of Earth Science 2018年第5期29卷 1181-1202页

作者： Hafizullah Abba Ahmed Changqian Ma Lianxun Wang Ladislav A.Palinkas Musa Bala Girei Yuxiang Zhu mukhtar Habib State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China Department of Geology Modibbo Adama University of TechnologyYola P.M.B.2076Nigeria Institute of Mineralogy and Petrology Faculty of SciencesUniversity of ZagrebZagreb HR-10000Croatia Department of Geology Faculty of Earth and Environmental SciencesBayero UniversityKanoNigeria Department of Mineral and Petroleum Resources Engineering Kaduna PolytechnicKadunaNigeria

In this study, we present systematic petrological, geochemical, LA-ICP-MS zircon U-Pb ages and Nd isotopic data for the A-type granites and syenites from Suizhou-Zaoyang region. The results show that the peralkaline A-type granites and syenites were episodically emplaced in Suizhou-Zaoyang region between 450±3 and 441±7 Ma which corresponds to Late Ordovician and Early Silurian periods, respectively. Petrologically, the syenite-peralkaline granite association comprises of nephefine normative-syenite and alkaline granite in Guanzishan and quartz normative syenite and alkafine granite in Huangyangshan. The syenite-granite associations are ferroan to alkali in composition. They depict characteristics of typical OIB （oceanic island basalts） derived A-type granites in multi-elements primitive normalized diagram and Ybffa vs. Y/Nb as well as Ce/Nb vs. Y/Nb binary plots. Significant depletion in Ba, Sr, P, Ti and Eu indicates fractionation of feldspars, biotite, amphiboles and Ti-rich augite. The values of eNd（t） in Guanzishan nepheline syenite and alkaline granite are ＋1.81 and ＋2.26, respectively and the calculated two-stage model age for these rocks are 1 040 and 1 003 Ma, respectively. On the other hand, the Huangyangshan alkaline granite has eNd（t） values ranging from ＋2.61 to ＋3.46 and a relatively younger two-stage Nd model age values ranging from 906 to 975 Ma, respectively. Based on these data, we inferred that the Guanzishan nepheline syenites and granites were formed from fractional crystallization of OIB-like basic magmas derived from upweliing of metasomatized lithospheric mantle. The Huangyangshan quartz syenite and granite on the other hand, were formed from similar magmas through fractional crystallization with low input from the ancient crustal rocks. Typically, the rocks exhibit Al-type granite affinity and classified as within plate granites associated with the Ordovician crustal extension and the Silurian rifting.

关键词： Huangyangshan Guanzishan OIB derived A-type granites nepheline syenite alkaline granite South Qinling Suizhou-Zaoyang region.

New Method for Diagnostics of Ion Implantation Induced Charge Carrier Traps in Micro- and Nanoelectronic Devices

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World Journal of Nuclear Science and Technology 2012年第4期2卷 174-180页

作者： mukhtar Ahmed Rana Physics Department International Islamic University Kashmir Highways Islamabad Pakistan

An important problem of defect charging in electron-hole plasma in a semiconductor electronic device is investigated using the analogy of dust charging in dusty plasmas. This investigation yielded physical picture of the problem along with the mathematical model. Charging and discharging mechanism of charge carrier traps in a semiconductor elec-tronic device is also given. Potential applications of the study in semiconductor device technology are discussed. It would be interesting to find out how dust acoustic waves in electron-hole plasma in micro and nanoelectronic devices can be useful in finding out charge carrier trap properties of impurities or defects which serve as dust particles in elec-tron-hole (e-h) plasma. A new method based on an established technique “deep level transient spectroscopy” (DLTS) is described here suggesting the determination of properties of charge carrier traps in present and future semiconductor devices by measuring the frequency of dust acoustic waves (DAW). Relationship between frequency of DAW and properties of traps is described mathematically proposing the basis of a technique, called here, dust mode frequency deep level transient spectroscopy (DMF-DLTS).

关键词： Semiconductors Ion Implantation Defects Dust Acoustic Waves Deep Level Transient Spectroscopy Electron-Hole Plasma Nanoelectronics

Metabolite profiling and antidiabetic attributes of ultrasonicated leaf extracts of Conocarpus lancifolius

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Asian Pacific Journal of Tropical Biomedicine 2020年第8期10卷 353-360页

作者： Syed Ali Raza Ayoub Rashid Chaudhary Muhammad Waseem Mumtaz Ahmad Adnan Hamid mukhtar Muhammad Tayyab Akhtar Department of Chemistry Government College UniversityLahore54000 Pakistan Department of Chemistry University of GujratGujrat Pakistan Institute of Industrial Biotechnology Government College UniversityLahore54000 Pakistan

Objective:To profile the secondary metabolites and to evaluate the antidiabetic potential of hydroethanolic leaf extracts of Conocarpus ***:The various hydroethanolic extracts of Conocarpus lancifolius leaf were prepared by ultrasonication assisted *** phenolic contents,flavonoid contents,antioxidant activity,α-glucosidase andα-amylase inhibitions of leaf extracts were *** metabolite profiling was accomplished by UHPLC-Q-TOF-MS/MS *** antidiabetic assessment of the most potent extract was carried out by measuring the hypoglycemic and hypolipidemic effect in the high fat diet-fed diabetic albino *** blood glucose level,haemoglobin,total cholesterol,high-density lipoproteins(HDL)and low-density lipoproteins(LDL)were ***:The 60%ethanolic extract exhibited the highest phenolic and flavonoid contents of(349.39±2.13)mg GAE/g dry extract and(116.95±2.34)mg RE/g dry extracts,respectively,and the highest DPPH scavenging activity with an IC50 value of(32.87±1.11)μg/*** IC50 values forα-glucosidase andα-amylase inhibitions were(38.64±0.93)μg/mL and(44.80±1.57)μg/mL,***-Q-TOF-MS/MS analysis confirmed the presence of gallic acid,ellagic acid,corilagin,kaempherol-3-O-rutinoside,caffeic acid derivative,isorhamnetin and galloyl derivatives in the 60%ethanolic *** extract at a dose of 450 mg/kg body weight reduced blood glucose level,total cholesterol,LDL and HDL,and increased haemoglobin in alloxan-induced diabetic mice,Conclusions:Conocarpus lancifolius leaves are proved as a good source of biologically functional metabolites and possess antidiabetic activity which may be further explored to treat diabetes.

关键词： Antioxidant Antidiabetic Conocarpus lancifolius Metabolite profiling Diabetic mice model

The Maghrebian Scholarship and the Development of Muslim Intelligentsias in Sub-Saharan Africa： A Case Study of the Central Bilad al-Sudan

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History Research 2013年第5期3卷 342-352页

作者： mukhtar Umar Bunza Usmanu Danfodiyo University Sokoto Nigeria

Central Bilad al-Sudan refers to the areas of the ancient Hausa states, and the domains of the ancient Kanem Bornu. As a result of the aged long commercial, cultural, and religious linkages between North Africa and the Central Sudan, one finds so many things in common among the two regions in dress, diets, cultural traits, as well as educational and religious practices. The extent of influence of the North African region on the individual and communal lives of the central Sudan has been extraordinarily great. The central Sudan is one of the most Islamized areas of West Africa, and Arabic language is second language to the Muslim communities in domestic and public spheres. And as a result of the entrenchment of Islam among the people due to the activities of North African scholars and traders the area became the hub of Islamic scholarship. The intellectual history of the Central Bilad al-Sudan cannot be complete without the mention of an Algerian scholar, Muhammad ibn Abd-A1-Kareem al-Maghili who in addition to his scholarly influence took appointment as Special Adviser in Kano in the 1460s. The same could be said of an Egyptian prolific writer, Jalal al-Deen al-Suyuti, who settled in Katsina and Gobir and also took the appointment of Grand Qadi in Katsina in the 15th century. Similarly, books of Sanhaja scholars, Shinqit Ulama＇a, as well as Spanish-Andalusian scholars via Morocco were made available and widely studied in this part of Muslim world. The combination of the activities of such scholars, literature, and learning tradition were responsible lbr the growth and development of Muslim intelligentsia in the central Bilad al-Sudan since the earliest time, and the influence continues to date. Thus this paper aims at examining the phenomenon, primarily by assessing the influence of scholars, literature, and educational institutions from the Maghreb on the intellectual development and the emergence of native scholars and intelligentsia and on the general scholarly t

关键词： the Maghreb scholarship central Sudan Northern Nigeria indigenous intelligentsia

Research and applications of nuclear tracks: Developments in Pakistan and global comparison

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Natural Science 2012年第11期4卷 950-967页

作者： mukhtar Ahmed Rana Instrument Development and Maintenance (IDM) Physics Division Pakistan Institute of Nuclear Science and Technology (PINSTECH) Islamabad Pakistan

The present paper describes the development and applications of nuclear track detection technique in Pakistan. Pakistan entered in the field of nuclear tracks in early 1970s when it was still quite new. Highlights of successes of different Pakistani laboratories, working on nuclear tracks, achieved on their own or in collaboration with similar centers in the world are described briefly. The robust features of this investigation are the comprehensive investigation of the addressed research, analysis and review of results, and discussions with the perspectives of applications and new research directions. Further analysis of the published results by the present author and some new results are also presented. This paper portrays a comprehensive picture of the nuclear track detection research and technology in Pakistan and can be useful for a similar development in any country around the globe.

关键词： Nuclear Tracks Latent Tracks Annealing Chemical Etching Radionuclides Nanotechnology Formatting

In Vitro Synthetic Seed Production of Potato under Different Fungicide Levels and Storage Intervals

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Phyton-International Journal of Experimental Botany 2023年第8期92卷 2429-2450页

作者： Tahira Kalsoom Touqeer Ahmed Muhammad Azam Khan Mirza Hasanuzzaman mukhtar Ahmed Stefaan P.O.Werbrouck Department of Horticulture PMAS-Arid Agriculture UniversityRawalpindi46300Pakistan Department of Agronomy Sher-e-Bangla Agricultural UniversityDhaka1207Bangladesh Department of Agronomy PMAS-Arid Agriculture UniversityRawalpindi46300Pakistan Department of Plants and Crops Ghent UniversityGhent9000Belgium

Potato propagation through tubers and seed is an inefﬁcient way of propagation thus we propose an alternative method in this study which is in vitro *** were raised from True Potato Seeds(TPS)in test tubes containing 10 mL of Murashige Skoog(MS)*** was done after every 21 days and after four subsequent subculturing,when there was an adequate quantity of stock material,uninodal cuttings of about 3-4 mm in length were prepared from in vitro proliferated potato plants by excising leaves of 1-2 mm on each side of the *** uninodal cuttings were cultured on 1/2 strength MS medium for root primordia *** selected uninodal cuttings with root primordia were encapsulated with sodium alginate solution(3.5%(w/v)),mixed with 1.25%charcoal and different concentration of fungicide(thiophanate methyl,sigma)to enhance the viability percentage of synthetic ***,these encapsulated uninodal cuttings were subjected to different storage intervals to check maximum *** showed that optimum dose for fungicide is 150 mg/L as it resulted in good viability percentage,shoot number,shoot length,rooting percentage,root number,root length and ideal for bead formation with sodium ***,results revealed that encapsulated uninodal cuttings can be stored at a temperature of 4℃ up to 45 days with a survival rate of 63.33%.Encapsulated uninodal cutting stored for 60 days showed a poor viability percentage of about 43.03%.It can be concluded that optimum dose of 150 mg/L with storage time of 45 days should be used to get a better outcome for synthetic potato seed production.

关键词： Synthetic seeds potato storage charcoal sodium alginate fungicide

Mining the Chatbot Brain to Improve COVID-19 Bot Response Accuracy

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Computers, Materials & Continua 2022年第2期70卷 2619-2638页

作者： mukhtar Ghaleb Yahya Almurtadha Fahad Algarni Monir Abdullah Emad Felemban Ali M.Alsharafi Mohamed Othman Khaled Ghilan Department of Information Systems College of Sciences and ArtsUniversity of BishaAl Namas67392Saudi Arabia Department of Computer Science College of Computing and Information TechnologyUniversity of TabukTabuk71491Saudi Arabia Department of Computer Science College of Computing and Information TechnologyUniversity of BishaBisha61922Saudi Arabia Computer Engineering Department Umm Al-Qura UniversityMakkah21955Saudi Arabia Department of Communication Technology and Network Universiti Putra MalaysiaSelangor43400Malaysia Faculty of Public Health and Tropical Medicine Jazan UniversityJazan45142Saudi Arabia

People often communicate with auto-answering tools such as conversational agents due to their 24/7 availability and unbiased ***,chatbots are normally designed for specific purposes and areas of experience and cannot answer questions outside their *** employ Natural Language Understanding(NLU)to infer their *** is a need for a chatbot that can learn from inquiries and expand its area of experience with *** chatbot must be able to build profiles representing intended topics in a similar way to the human brain for fast *** study proposes a methodology to enhance a chatbot’s brain functionality by clustering available knowledge bases on sets of related themes and building representative *** used a COVID-19 information dataset to evaluate the proposed *** pandemic has been accompanied by an“infodemic”of fake *** chatbot was evaluated by a medical doctor and a public trial of 308 real *** obtained and statistically analyzed tomeasure effectiveness,efficiency,and satisfaction as described by the ISO9214 *** proposed COVID-19 chatbot system relieves doctors from answering *** provide an example of the use of technology to handle an infodemic.

关键词： Machine learning text classification e-health chatbot COVID-19 awareness natural language understanding

Dosimetric Performance of A-Si Electronic Portal Imaging Devices

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2016年第2期5卷 162-175页

作者： mukhtar Alshanqity Andrew Nisbet Medical Physics Department Comprehensive Cancer Centre King Fahad Medical City Riyadh Saudi Arabia Centre for Nuclear and Radiation Physics Physics Department University of Surrey Guildford UK

The majority of EPID dosimetry literature discusses response linearity and the so-called image lag and ghosting effects despite the lack of a common definition of these quantities. However, the results of these studies are generally not consistent, and it is often difficult to compare the results from different studies. We present here a detailed study of the acquisition and readout characteristics of a-Si EPID and its dosimetric performance. EPID response was assessed over the range of 1 - 500 MU using different dose rates and integration times. In addition, a computer model was designed to simulate the EPID image formation with different dose, dose rate, and integration time combinations. All aspects of image processing and readout simulation were carried out using custom written MatLab codes. Two distinct signal profiles were observed depending on the delivered dose, dose rate and integration time combination. Total integrated signal (ST) is linear with the delivered dose. For dosimetry, image lag and ghosting effects mainly result in the residual signal (SR) that appears as delayed signal after the end of irradiation. At its maximum, SR is less than 2.5% of ST. The readout technique is such that it is impossible to measure SR accurately. SR is definable only when readout equilibrium occurs. Signal profiles provide a through and reliable description of the EPID response incorporating the dose, dose rate, integration time, and the residual signal. The definition of EPID signals based on this method shall provide an accurate universal EPID dosimetry framework.

关键词： EPID Portal Dosimetry Radiotherapy QA

Channeling in Bent Crystallites: A New Method to Enhance the Radiation Shielding Efficiency

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Modern Instrumentation 2018年第3期7卷 35-41页

作者： mukhtar Ahmed Rana Medical Equipment Research and Development Division (MERADD) ICCC Lahore Pakistan

A new method is proposed here aiming at designing a shielding wall with the efficiency significantly higher than that of traditional designs. This new design arises from the idea of using channeling in multilayered shielding wall structure, each layer composed of bent crystallites distributed in a way that each layer covers a small section of 2π angular range of which wall is exposed. Part of the incident charged particles will get channeled in bent crystallites in each layer. Bending of channeled particles in bent crystallites will change their directions in the wall increasing their path lengths in the wall which would enhance its shielding efficiency for charged particle radiations. Proposed design is useful for radiation shielding in fission power plants, future fusion reactors and air travel.

关键词： Radiation Shielding Bent Crystals Channeling Nuclear and Thermonuclear Reactors Cosmic Rays