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Plasma Science and Technology 2021年第2期23卷 17-29页

作者： Hafiz Imran Ahmad QAZI Muhammad ajmal khan Jianjun HUANG SZU-CASIPP Joint Laboratory for Applied Plasma College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060People's Republic of China Department of Engineering Physics Tsinghua UniversityBeijing 100084People's Republic of China

A discharge ignited by an AC power source in contact with deionized water as one of the electrodes is *** after initiation,the discharge exhibits a unique phenomenon:the gas-phase discharge is extended into the ***,a cone-like structure is observed at the liquid *** monitoring of current–voltage characteristics and liquid properties versus time suggests that the discharge shapes are functions of the liquid *** spatio-temporal profiles indicate the potential effects of water,ambient air impurities,and metastable argon on the discharge *** becomes more obvious near the liquid surface due to increasing production of various transient reactive species such as centerdot OH and NO ***,it is revealed that thermalization of the rotational population distributions of the rotational states(N′⩽6,J′⩽13/2)in the Q1 branch of the OH(A2Σ+,υ′=0→X2Π3/2,υ′′=0)band ro-vibrational system is influenced by the humid environment near the liquid *** addition,the transient behaviors of instantaneous concentrations of long-lived reactive species(LRS)such as H2O2,NO−2,and NO−3 are observed with lengthening the discharge *** production of multiple transient and LRS proposes AC excited gas–liquid argon discharge as a potential applicant in industrial wastewater cleaning,clinical medicine,and agriculture.

关键词： gas–liquid interface discharge emission patterns rotational temperature plasma chemistry

Petroleum hydrocarbon distribution in continental shelf region of southeast coast of India

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International Journal of Sediment Research 2012年第1期27卷 73-83页

作者： Somasundaran LYLA Seerangan MANOKARAN ajmal khan Centre of Advanced Study in Marine Biology Annamalai UniversityParangipettaiTamilNadu-608 502India Assoc.Prof. Centre of Advanced Study in Marine Biology Annamalai UniversityParangipettai -608 502Tamil NaduIndia Researcher Centre of Advanced Study in Marine Biology Annamalai UniversityParangipettai -608 502Tamil NaduIndia Prof.Emeritus

In the surface sediment samples collected from 7 transects in the continental shelf region off Karaikkal,Parangipettai,Cuddalore-SIPCOT,Cheyyur,Chennai,Tammenapatanam and Singarayakonda in the southeast coast of India at the depths of 30m,50m,75m,100m,150m and 200m,the petroleum hydrocarbon(PHC) varied from 1.582μg/g(Karaikkal 150m) to 4.065 ug/g (Cheyyur 75m).The correlation between PHC and organic carbon content was not significant. However PHC and mean particle diameter showed significant negative correlation(P<0.01).In Singarayakonda transect,the nature of the sediment was silty at all the depths(except 30m - coarse sand) and consequently the average concentrations of PHC and total organic carbon(TOC)(2.844μg/g and 2.864 mg/g) were *** is attributed to the influence of rivers Krishna,Gundlakamma, Polleru and Uppuino which discharge more sediment besides agricultural runoff and urban sewage. The average concentration of PHC in Cheyyur,Cuddalore - SIPCOT and Parangipettai transects was 2.818,2.332 and 2.324μg/g *** is attributed to the influence of rivers in these areas(Palar, Gaddillam,Uppanar,Vellar and Coleroon) besides Kalpakkam Atomic Power Station and industrial discharges from *** the Canonical Analysis of Principal Coordinates(CAP) plot,the first axis explained about 51.84%of the variability and the second 18.67%(totally the first two axes explained 70.51%of the variability).The canonical correlation values of first 2 axes were 0.7497 and 0.5865 *** PHC level observed in the present study was found to be lower than the levels reported from other *** the coastal region in the study area continues to grow in all the dimensions economically,continuous monitoring of PHC is quite essential especially the three fractions pyrolytic,petrogenic and biogeneic fractions of PHC.

关键词： Petroleum hydrocarbons Continental shelf Canonical analysis of principals coordinates Bay of Bengal

Regio-and enantioselective formation of tetrazole-bearing quaternary stereocenters via palladium-catalyzed allylic amination

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Organic Chemistry Frontiers 2022年第2期9卷 456-461页

作者： Shahid khan Yu Wang Mei-Na Zhang Shahida Perveen Junjie Zhang ajmal khan Department of Chemistry School of ChemistryXi’an Key Laboratory of Sustainable Energy Materials Chemistry and MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed MatterXi’an Jiao Tong UniversityXi’an 710049P.R.China

Based on palladium-catalyzed allylic amination reaction,the first general example of enantioselective formation of a tetrazole-bearing quaternary stereocenter has been *** protocol uses ambivalent tetrazole and vinyl cyclic carbonates as easily available coupling *** operationally simple methodology is further characterized by its wide substrate scope,high enantioselectivity and excellent branched to linear regioselectivity,thus unlocking a new platform that permits the synthesis of elusive quaternary N2-allylic tetrazoles,even in the context of late-stage functionalization.

关键词： quaternary palladium catalyzed

Assessment of Genetic Variation Within Indian Mustard (Brassica juncea) Germplasm Using Random Amplified Polymorphic DNA Markers

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Journal of Integrative Plant Biology 2008年第4期50卷 385-392页

作者： Muhammad Ayub khan Malik Ashiq Rabbani Muhammad Munir Saifullah khan ajmal Muhammad Azim Malik Oilseed Research Program National Agricultural Research Center Park Road Islamabad 45500 Pakistan Institute of Agri-Biotechnology & Genetic Resources National Agricultural Research Center Park Road Islamabad 45500 Pakistan University of Arid Agriculture Rawalpindi Pakistan

Genetic diversity among 45 Indian mustard （Brassica juncea L.） genotypes comprising 37 germplasm collections, five advance breeding lines and three improved cultivars was investigated at the DNA level using the random amplified polymorphic DNA （RAPD） technique. Fifteen primers used generated a total of 92 RAPD fragments, of which 81 （88%） were polymorphic. Of these, 13 were unique to accession ‘Pak85559＇. Each primer produced four to nine amplified products with an average of 6.13 bands per primer. Based on pairwise comparisons of RAPD amplification products, Nei and Li＇s similarity coefficients were calculated to evaluate the relationships among the accessions. Pairwise similarity indices were higher among the oilseed accessions and cultivars showing narrow ranges of 0.77-0.99. An unweighted pair-group method with arithmetic averages cluster analysis based on these genetic similarities placed most of the collections and oilseed cultivars close to each other, showing a low level of polymorphism between the accessions used. However, the clusters formed by oilseed collections and cultivars were comparatively distinct from that of advanced breeding lines. Genetically, all of the accessions were classified into a few major groups and a number of individual accessions. Advanced breeding lines were relatively divergent from the rest of the accessions and formed independent clusters. Clustering of the accessions did not show any pattern of association between the RAPD markers and the collection sites. A low level of genetic variability of oilseed mustard was attributed to the selection for similar traits and horticultural uses. Perhaps close parentage of these accessions further contributed towards their little diversity. The study demonstrated that RAPD is a simple and fast technique to compare the genetic relationship and pattern of variation among the gene pool of this crop.

关键词： Brassica juncea genetic diversity germplasm oilseed mustard Pakistan random amplified polymorphic DNA.

Sedative and antinociceptive activities of two new sesquiterpenes isolated from Ricinus communis

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Chinese Journal of Natural Medicines 2018年第3期16卷 225-230页

作者： Umar Farooq ajmal khan Sadia Naz Abdur Rauf Haroon khan Afsar khan Irfan Ullah Syed Majid Bukhari Department of Chemistry COMSATS Institute of Information Technology UoN Chair of Oman's Medicinal Plants and Marine Natural Products University of Nizwa Department of Geology University of Swabi Anbar Department of Pharmacy Abdul Wali Khan University Department of Pharmacy Abasyn University

Two new sesquiterpenes, trivially named ricinusoids A(1) and ricinusoids B(2), were isolated from ethyl acetate fraction of Ricinus communis. The structures of new compounds were elucidated by detailed spectroscopic techniques, including 1 D-and 2 D-NMR, UV, IR spectroscopy, and mass spectrometry. The compounds(1-2) were also assessed for in-vivo sedative and analgesic like effects in open field and acetic acid induced writhing tests respectively at 5, 10, and 20 mg·kg^(–1) i.p. Pretreatment of both test compounds caused significant(P ≤ 0.05) reduction in locomotive activity like sedative agents and abdominal constrictions like analgesics. Both compounds(1-2) possessed marked sedative and antinociceptive effects in animal models.

关键词： Ricinus communis Sesquiterpenoids Euphorbiaceae Spectroscopic techniques Antinociceptive activity

EA-RDSP: Energy Aware Rapidly Deployable Wireless Ad hoc System for Post Disaster Management

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Computers, Materials & Continua 2021年第11期69卷 1725-1746页

作者： ajmal khan Mubashir Mukhtar Farman Ullah Muhammad Bilal Kyung-Sup Kwak Department of Electrical and Computer Engineering COMSATS University IslamabadAttock43600Pakistan Division of Computer and Electronics Systems Engineering Hankuk University of Foreign StudiesYongin-si17035Korea Department of Information and Communication Engineering Inha UniversityIncheon22212Korea

In post disaster scenarios such as war zones floods and earthquakes,the cellular communication infrastructure can be lost or severely *** such emergency situations,remaining in contact with other rescue response teams in order to provide inputs for both headquarters and disaster survivors becomes very ***,in this research work,a design,implementation and evaluation of energy aware rapidly deployable system named EA-RDSP is *** proposed research work assists the early rescue workers and victims to transmit their location information towards the remotely located *** EA-RDSP,two algorithms are proposed i.e.,Hop count Assignment(HCA)algorithm and Maximum Neighbor Selection(MNS)*** EA-RDSP contains three types of nodes;the client node sends information about casualty in the disaster area to the server,the relay nodes transmit this information from client node to server nodes via multi-hop transmission,the server node receives messages sent by client node to alert rescue *** EAM-RDSP contains three types of nodes;the client node sends information about casualty in the disaster area to the server,the relay nodes transmit this information from client node to server nodes via multi-hop transmission,the server node receives messages sent by client node to alert rescue *** proposed EA-RDSP scheme is simulated using NS2 simulator and its performance is compared with existing scheme in terms of end-to-end delay,message delivery ratio,network overhead and energy consumption.

关键词： Disaster management neighbor selection device-to-device communication multi-hop relaying energy efficiency

Distribution and generic composition of culturable marine actinomycetes from the sediments of Indian continental slope of Bay of Bengal

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Chinese Journal of Oceanology and Limnology 2008年第2期26卷 166-177页

作者： Surajit DAS P. S. LYLA S. ajmal khan Centre of Advanced Study in Marine Biology Annamalai University Parangipettai-608 502 Tamil Nadu India

Actinomycetes population from continental slope sediment of the Bay of Bengal was studied. Samples were collected during two voyages of FORV Sagar Sampada in 2004 （May-June） and 2005 （July） respectively from 11 transects （each transect had ca. 200 m, 500 m, and 1 000 m depth stations）. The physicochemical parameters of overlying water, and sediment samples were also recorded. The actinomycete population ranged from 5.17 to 51.94 CFU/g dry sediment weight and 9.38 to 45.22 CFU/g dry sediment weight during the two cruises respectively. No actinomycete colony was isolated from stations in 1 000 m depth. Two-way analysis of variance showed significant variation among stations （ANOVA two-way, P〈0.05）, but no significance was found between the two cruises （ANOVA two-way, P〈0.05）. Populations in stations in 500 m depth in both cruises were higher than that of 200 m depth stations with statistically insignificant difference （ANOVA two-way, P〉0.05）. Three actinomycetes genera were identified. Streptomyces was found to be the dominating one in both the cruises, followed by Micromonospora, and Actinomyces. The spore of Streptomyces isolates showed the abundance in spiral spore chain. Spore surface was smooth. Multiple regression analysis revealed that the influencing physico-chemical factors were sediment pH, sediment temperature, TOC, porosity, salinity, and pressure. The media used in the present study was prepared with seawater. Thus, they may represent an autochthonous marine flora and deny the theory of land runoff carriage into the sea for adaptation to the salinity of the seawater and sediments.

关键词： marine actinomycetes generic composition physico-chemical parameters continental slope Bay of Bengal

Impact of a biochar or a biochar-compost mixture on water relation, nutrient uptake and photosynthesis of Phragmites karka

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Pedosphere 2020年第4期30卷 466-477页

作者： Zainul ABIDEEN Hans-Werner KOYRO Bernhard HUCHZERMEYER Bilquees GUL M.ajmal khan Institute of Sustainable Halophyte Utilization University of KarachiKarachi 75270(Pakistan) Institute of Plant Ecology Justus Liebig University GiessenGiessen D-35392(Germany) Institute of Botany Gottfried Wilhelm Leibniz UniversityHannover D-30419(Germany)

Soil water and nutrient status are both of major importance for plant appearance and growth *** objective of this study was to understand the effect of biochar(1.5%)and a biochar-compost mixture(1.5%biochar+1.5%compost)on the performance of Phragmites karka plants grown on a synthetic nutrient-poor sandy clay soil(50% sand,30% clay,and 20% gravel).Indicators of plant performance,such as growth,lignocellulosic biomass,water status(leaf water potential,osmotic potential,and turgor potential),mineral nutrition status,leaf gas exchange,and chlorophyll fluorescence,and soil respiration(carbon dioxide(CO2)flux)were assessed under greenhouse ***-treated plants had higher growth rates and lignocellulosic biomass production than control plants with no biochar and no *** was also a significant increase in soil respiration in the treatments with biochar,which stimulated microbial *** increase in soil water-holding capacity after biochar amendment caused significant improvements in plant water status and plant ion(K^+,Mg^2+,and Ca^2+)contents,leading to an increase in net photosynthesis and a higher energy-use efficiency of photosystem ***-treated plants had lower oxidative stress,increased water-use efficiency,and decreased soil respiration,and the biochar-compost mixture resulted in even greater improvements in growth,leaf turgor potential,photosynthesis,nutrient content,and soil gas *** results suggest that biochar and compost promote plant growth with respect to nutrient uptake,water balance,and photosynthetic system *** summary,both the soil amendments studied could increase opportunities for *** to sequester CO2 and produce more fodder bio-active compounds and biomass for bio-energy on nutrient-poor degraded soils.

关键词： bio-energy crop chlorophyll fluorescence degraded soil plant eco-physiology plant growth photochemical efficiency water status

Bioassay-guided isolation of novel and selective urease inhibitors from Diospyros lotus

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Chinese Journal of Natural Medicines 2017年第11期15卷 865-870页

作者： Abdur Rauf Ghias Uddin Bina S. Siddiqui ajmal khan Umar Farooq Farhan A. khan Syed Majid Bukhari Sher Bahadar khan Department of Chemistry University ofSwabi Anbar-23561 Khyber Pakhtunkhwa Pakistan Institute of Chemical Sciences University ofPeshawar Peshawar-25120 Pakistan H.E.J. Research Institute of Chemistry International Center for Chemical and Biological Sciences University ofKarachL Ka- rachi- 75270 Pakistan Department of Chemistry COMSAT Institute of Information Technology Abbottabad-22060 Pakistan UoN Chair of Oman 's Medicinal Plants and Marine Natural Products University ofNizwa Birkat Al-Mouz Nizwa-616 Oman Center of Excellence for Advanced Materials Research (CEAMR) Department of Chemistry Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia Kingdom

Two new dimeric naphthoquinones, 5′,8′-dihydroxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraone(1; Di-naphthodiospyrol D) and 5′,8′-dihydroxy-5,8-dimethoxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraone(2; Di-naphthodiospyrol E), along with known naphthoquinones diospyrin(3) and 8-hydroxy diospyrin(4) were isolated from the chloroform fraction of extract of Diospyros lotus roots. Their structures were elucidated by advanced spectroscopic analyses, including HSQC, HMBC, NOESY, and J-resolved NMR experiments. The fractions and compounds 1-4 were evaluated for urease activity and phosphodiesterase-Ⅰ, carbonic anhydrase-Ⅱ and α-chymotrypsin enzyme inhibitory activities. Compounds 1 and 2 and their corresponding fractions showed significant and selective inhibitory effects on urease activities. The IC_(50) values of 1 and 2 were 260.4 ± 6.37 and 381.4 ± 4.80 μmol·L-1, respectively, using thiourea(IC_(50) = 21 ± 0.11 μmol·L^(-1)) as the standard inhibitor. This was the first report demonstrating that the naphthoquinones class showed urease inhibition.

关键词： Diospyros lotus Naphthoquinones Phosphodiesterase-Ⅰ Carbonic anhydrase-Ⅱ α-Chymotrypsin Urease inhibitory activities

Physicochemical properties of the AC- excited helium discharges using a water electrode

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Plasma Science and Technology 2018年第7期20卷 112-120页

作者： Hafiz Imran Ahmad QAZI Yiying XIN Muhammad ajmal khan Heping LI Lu ZHOU Chengyu BAO Department of Engineering Physics Tsinghua University Beijing 100084 People's Republic of China School of Environment Tsinghua University Beijing 100084 People's Republic of China

In this paper, the AC-excited helium discharges generated between the powered needle electrode enclosed in a conical quartz tube and the grounded de-ionized water electrode are investigated. The current and voltage waveforms exhibit a transition from the glow-like to streamer-like mode discharges, which forms a stable cone-shaped structure at the gas-liquid interface. In this region, the air and water vapor diffusion initiate various physical-chemical processes leading to substantial changes of the primary species emission intensities （e.g., OH, N2, NO, and O） and the rotational temperatures. The experimentally measured rotational temperature at the gas-liquid interface is 870 K from the Nz（C-B） band with a power input of 26 W. With the prolongation of the discharge time, significant changes in the discharge voltage and current, discharge emission patterns, instantaneous concentrations of the secondary species （e.g., H202, NO2, and NO3） in the liquid phase, pH values and electrical conductivities of the liquids are observed experimentally. The present study is helpful for deepening the understandings to the basic physical-chemical processes in the discharges in contact with liquids, especially to those occurring in the vicinity of the gas-liquid interface, and also for promoting existing and potential applications of such type of discharges in the fields of environmental protection, biomedicine, agriculture, and so on.

关键词： solution plasma gas-liquid interface wastewater treatment biomedical science and agriculture applications