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Degradation of ^(14)C-glyphosate and aminomethylphosphonic acid (AMPA) in three agricultural soils

Journal of Environmental Sciences 2010年第9期22卷 1374-1380页

作者： abdul jabbar al-rajab Michel Schiavon Laboratory of Soil and Environmental Sciences 54505 Vandoeuvre-lès-Nancy Cedex France Agriculture and Agri-Food Canada London Ontario N5V 4T3 Canada

Glyphosate （N-phosphonomethyl glycine） is the most used herbicide worldwide. The degradation of ^14C-labeled glyphosate was studied under controlled laboratory conditions in three different agricultural soils： a silt clay loam, a clay loam and a sandy loam soil. The kinetic and intensity of glyphosate degradation varied considerably over time within the same soil and among different types of soil. Our results demonstrated that the mineralization rate of glyphosate was high at the beginning of incubation and then decreased with time until the end of the experiment. The same kinetic was observed for the water extractable residues. The degradation of glyphosate was rapid in the soil with low adsorption capacity （clay loam soil） with a short half-life of 4 days. However, the persistence of glyphosate in high adsorption capacity soils increased, with half-live of 19 days for silt clay loam soil and 14.5 days for sandy loam soil. HPLC analyses showed that the main metabolite of glyphosate, arninomethylphosphonic acid （AMPA） was detected after three days of incubation in the extracts of all three soils. Our results suggested that the possibility of contamination of groundwater by glyphosate was high on a long-term period in soils with high adsorption capacity and low degrading activities and/or acid similar to sandy loam soil. This risk might be faster but less sustainable in soil with low adsorption capacity and high degrading activity like the clay loam soil. However, the release of non-extractable residues may increase the risk of contamination of groundwater regardless of the type of soil.

关键词： glyphosate aminomethylphosphonic acid (AMPA) mineralization degradation soil

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Chemical composition, antibacterial and antifungal activities of Saudi Arabian Mentha longifolia L. essential oil

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Journal of Coastal Life Medicine 2017年第10期5卷 441-446页

作者： Nagarjuna Reddy Desam abdul jabbar al-rajab Mukul Sharma Mary Moses Mylabathula Ramachandra Reddy Gowkanapalli albratty Mohammed Center for Environmental Research and Studies Jazan UniversityJazanSaudi Arabia Department of Biotechnology College of ScienceKrishna UniversityMachilipatnamA.P.India Department of Polymer science and Technology College of ScienceAnatapuramA.P.India Department of Pharmaceutical Chemistry Faculty of PharmacyJazan UniversityJazanSaudi Arabia

Objective: To investigate the chemical composition, in vitro antibacterial and antifungal activity of Mentha longifolia L. essential oils using aqueous extract. Methods: Mentha longifolia L. essential oils were extracted using hydrodistillation with Clevenger apparatus for 3 h and the yield of the essential oil was calculated. Essential oils were qualitatively and quantitatively analyzed with gas chromatography and gas chromatography-mass spectrometer. For these essential oils, antibacterial and antifungal activity against human pathogens were evaluated. Results: Nineteen chemical constituents representing 99.72% of the essential oil were found, comprising menthone (39.55%), isopulegone (30.49%), eucalyptol (10.38%), and α-terpineol (3.15%);these were major components, and others were minor components. The essential oil showed strong antibacterial activity against Staphylococcus aureus [(35.24 ± 0.13) mm], Enterococcus faecalis [(32.12 ± 0.12) mm] and Bacillus cereus [(30.06 ± 0.04) mm], as well as antifungal activity against Aspergillus flavus [(38.02 ± 0.06) mm], alternaria alternaria [(35.26 ± 0.12) mm], and Penicillum spp ((34.14 ± 0.02) mm)Conclusions: It seems that the essential oils derived from the Mentha longifolia L. species could be used as a natural source of antimicrobial agents.

关键词： Chemical composition Essential oil Antibacterial Antifungal Mentha longifolia L. Menthone Isopulegone Eucalyptol

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Electric-field induced fluctuations in laser generated plasma plume

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Plasma Science and Technology 2021年第4期23卷 83-89页

作者： Rizwan AHMED abdul jabbar Zeshan Adeel UMAR Muhammad Aslam BAIG National Centre for Physics Quaid-i-Azam University Campus45320 IslamabadPakistan

The effect of an external electric field on laser-generated plasma has been *** is observed that the laser-generated plasma can be used for the ignition of a spark in the presence of a low voltage external electric *** eight-fold emission intensity enhancement in Cu I spectral lines are measured as compared to the signal intensity in the absence of an external electric *** plasma parameters remain the same initially,up to a few microseconds after the generation of plasma,and this feature makes it more interesting for the quantitative analysis of any sample using laser induced breakdown spectroscopy(LIBS).In the presence of an external electric field,fluctuations(contraction and expansion)in the laser-generated plasma are observed which increase the plasma decay time and consequently result in enhanced signal intensity.

关键词： LIBS laser produced plasma effect of external electric plasma parameters

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Radioactive contents and background doses from northern alluvial sediment plains between rivers Ravi and Chenab,Pakistan

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Nuclear Science and Techniques 2016年第4期27卷 127-134页

作者： abdul jabbar Khalid Khan Tania jabbar Muhammad Rafique S.U.Rehman Waheed Arshed Muhammad Dilband Health Physics Division Pakistan Institute of Nuclear Science and Technology (PINSTECH) Department of Physics University of Azad Jammu and Kashmir Muzaffarbad Department of Medical Physics Nuclear Medicine Oncology and Radiotherapy Institute (NORI)

Radiometric analysis of soil samples, collected from northern alluvial sediment plains between rivers Ravi and Chenab, has been carried out. Activity concentrations of^(226) Ra,^(232)Th,^(40) K and the artificial radionuclide^(137) Cs were estimated by using high-purity germanium detector. Subsequent values of activity concentrations were used to find terrestrial absorbed dose rate and annual effective doses received by resident of area. The mean radioactivity levels of^(226) Ra,^(232)Th,^(40) K and^(137)Cs were found to be 45.0 ± 1.3,59.6 ± 2.8, 613.8 ± 20.0 and 4.0 ± 0.2 Bq kg^(-1), respectively. Terrestrial absorbed dose rate and annual effective dose received by public were found to be 85.1 n Gy h^(-1)and0.5 m Sv, respectively. The activity concentrations of^(226) Ra,^(232)Th,^(40) K and^(137)Cs and resulting doses obtained for the current study were compared with data available in the literature and with international standards.

关键词：年有效剂量冲积平原平原河流放射性含量巴基斯坦泥沙 137Cs 226Ra

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Antihypertensive efficacy of extract of Hedera helix in high salt-induced hypertensive Sprague-Dawley rats

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Asian Pacific Journal of Tropical Medicine 2018年第8期11卷 473-479页

作者： Umme Salma Taous Khan abdul jabbar Shah Cardiovascular Research Group Department of Pharmacy COMSATS University IslamabadAbbottabad campus

Objective: To explore the antihypertensive effect of extracts from the leaves of Hedera helix(H. helix) on normotensive and hypertensive rats in-vivo followed by vasodilatory studies ***: The crude methanolic extract was prepared and the activity directed fractionation was carried out. Spectrophotometric analysis of total phenolic and flavonoid content was also done. HPLC analysis was performed for the detection of hederacoside C. In-vivo blood pressure study was carried out in normotensive and high salt-induced hypertensive SpragueDawley rats. Isolated aortic tissues from rat and rabbit were used for in-vitro studies. The effects were recorded and analyzed through PowerL ab data acquisition system. Results: Crude extract of H. helix(1-30 mg/kg) decreased blood pressure to greater extent in high salt-induced hypertensive rats in-vivo compared to the normotensive [Max. fall(58.59±0.02) mm Hg vs.(67.53±3.07) mmH g]. The n-hexane, chloroform, ethyl acetate and aqueous fractions were also checked. These fractions were more effective in hypertensive rats. Aqueous fraction was more potent and n-hexane the least. In isolated rat aortic rings precontracted with phenylephrine, crude extract induced endothelium-dependent effect. The endothelium-dependent component of vasodilatory effect was ablated with L-NAME, and denudation of endothelium. The aqueous fraction was most potent vasodilator. In aortic rings from hypertensive rats, extract and fractions produced partial endothelium-independent effect which was not affected by pretreatment with L-NAME, indicating endothelium dysfunction in the hypertensive rats and suggesting additional vasodilatory mechanisms. In rabbit aorta, the extract and fractions also inhibited phenylephrine and high K^+-induced precontractions, and shifted Ca^(++) concentration–response curves. Conclusions: Our findings indicate that extract and fractions of H. helix are antihypertensive remedies, which is the outcome of vasodilatory effect.

关键词： Hedera helix Antihypertensive Vasorelaxant Endothelium-dependent Nitric oxide Calcium channel blocker

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Leveraging the Role of Dynamic Reconfigurable Antennas in Viewpoint of Industry 4.0 and Beyond

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Research 2023年第3期6卷 35-56页

作者： abdul jabbar Muhammad ali Jamshed Qammer Abbasi Muhammad ali Imran Masood Ur-Rehman James Watt School of Engineering University of GlasgowGlasgowUK

Industry 4.0 is a digital paradigm that refers to the integration of cutting-edge computing and digital technologies into global industries because of which the state of manufacturing,communication,and control of smart industries has changed *** 4.0 has been profoundly influenced by some major disruptive technologies such as the Internet of Things(IoT),smart sensors,machine learning and artificial intelligence,cloud computing,big data analytics,advanced robotics,augmented reality,3D printing,and smart adaptive *** this review paper,we discuss physical layer-based solutions with a focus on high reliability and seamless connectivity for Industry 4.0 and beyond ***,we present a harmonized review of the industrial revolution journey,industrial communication infrastructure,key performance requirements,and potential sub-6-GHz frequency ***,based on that,we present a comprehensive review of intelligent tunable dynamic antenna systems at sub-6 GHz as key enablers for next-generation smart industrial ***-of-the-art smart antenna techniques such as agile pattern reconfigurability using electrical components,machine learning-and artificial intelligence-based agile beam-scanning antennas,and beam-steerable dynamic metasurface antennas are thoroughly reviewed and *** unfolded the exciting prospects of reconfigurable dynamic antennas for intelligent and reliable connectivity in application scenarios of Industry 4.0 and beyond such as Industrial IoT and smart manufacturing.

关键词： antenna IoT smart

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Microwave-assisted catalytic oxidative desulfurization of gasoil fuel using synthesized CuO-ZnO nanocomposites

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燃料化学学报 2019年第9期47卷 1075-1082页

作者： Mustafa H.Fadhil Saad H.Ammar Marwa F.abdul jabbar Chemical Engineering Department Al-Nahrain University

Recently, organosulfur removal from liquid petroleum fuels is very significant aspect of environment protecting and fuel cell requests. Therefore, improved approaches to remove sulfur are still essential. In the present work, a simple catalytic oxidative desulfurization (CODS) system for Iraqi gasoil fraction has been successfully developed using CuO-ZnO nanocomposites as catalysts, and H 2O 2 as oxidant under microwave irradiation. The main reaction parameters influencing sulfur conversion including microwave power, irradiation time, catalyst dosage and H 2O 2 to gasoil volume ratio have been investigated. The CuO-ZnO nanocomposites was synthesized with different weight ratios and characterized by XRD, FE-SEM, AFM and BET surface area methods. The results reveal that, high sulfur conversion (93%) has been achieved under suitable conditions of microwave CODS as follows: microwave power of 540 W, irradiation time of 15 min, catalyst dosage of 8 g/L (0.4 g), and H 2O 2 ∶gasoil volume ratio of 0.3. The catalyst reusability shows that the synthesized catalyst can be reused five times without an important loss in its activity.

关键词： microwave oxidative desulfurization nanocomposites catalyst gasoil

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Synthesis and superconductivity of（Ag）x/CuTl-1223 composites

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Progress in Natural Science:Materials International 2015年第3期25卷 204-208页

作者： abdul jabbar Irfan Qasim M.Mumtaz K.Nadeem Materials Research Laboratory Department of PhysicsFaculty of Basic and Applied Sciences(FBAS)International Islamic University(IIU)

Series of(Ag)x/(Cu0.5Tl0.5Ba2Ca2Cu3O10-δ) {(Ag)x/Cu Tl-1223} nano-superconductor composites were synthesized with different concentrations(i.e. x ? 0 4.0 wt%) of silver(Ag) nanoparticles. Low anisotropic Cu Tl-1223 superconducting matrix was prepared by solid-state reaction and Ag nanoparticles were prepared by a sol–gel method separately. The required(Ag)x/Cu Tl-1223 composition was obtained by the inclusion of Ag nanoparticles in Cu Tl-1223 superconducting matrix. Structural, morphological, compositional and superconducting transport properties of these composites were investigated in detail by x-ray diffraction(XRD), scanning electron microscopy(SEM), energy dispersive x-rays(EDX)spectroscopy and four-point probe electrical resistivity(ρ) measurements. The inclusion of Ag nanoparticles enhanced the superconducting properties without affecting the tetragonal structure of the host Cu Tl-1223 matrix. The improvement in superconducting properties of(Ag)x/Cu Tl-1223 composites is most likely due to enhanced inter-grains coupling and increased superconducting volume fraction after the addition of metallic Ag nanoparticles at the inter-crystallite sites in the samples. The presence of Ag nanoparticles at the grain-boundaries may increase the number of flux pinning centers, which were present in the form of weak-links in the pure Cu Tl-1223 superconducting matrix.

关键词： (Ag)x/CuTl-1223 composites Ag nanoparticles weak-links superconducting properties

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Radionuclide concentrations in sand samples from riverbanks of Muzaffarabad,Azad Kashmir

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Nuclear Science and Techniques 2018年第7期29卷 103-115页

作者： abdul Razzaq Khan Muhammad Rafique abdul jabbar Saeed Ur Rahman Muhammad Ikram Shahzad Muhammad Ejaiz Khan Mulaika Yasin Department of Physics University of Azad Jammu andKashmir MuzaffarbadAzad Kashmir 13100Pakistan Health Physics Division Pakistan Institute of NuclearScience and Engineering(PINSTECH)NiloreIslamabad 45650Pakistan Department of Medical Physics Nuclear MedicineOncologyand Radiotherapy InstituteIslamabadPakistan Physics Division Directorate of SciencePINSTECHP.O.NiloreIslamabad 45650Pakistan

This paper presents the results of a radiological risk assessment arising from the presence of naturally occurring radionuclides in sand samples from three riverbanks in *** mean values obtained for 232 Th,226 Ra,and 40 K were found to be 44.58 ± 3.34,48.25 ± 1.77,and 239.92 ± 22.73 Bq kg^(-1),*** assess the uniformity of exposure,the radium equivalent activity(Raeq) was calculated and was found to be130.47 ± 8.29 Bqkg^(-1).The current reported value for Raeqis lower than the maximum permissible value,that is,370 Bq kg^(-1),and equivalent to a gamma dose of1.5 m Svy^(-1).To investigate the possible contribution to health risks of alpha particle exposure,the radon exhalation rate(RER) from the sand samples was *** mean RER for all the samples was found to be335 m Bq m-^(2) h^(-1).About 43% of the samples were found to have an indoor excess lifetime cancer risk value slightly higher than recommended safety limit of 1,as proposed by the ICRP.A normalized parameter,the equivalent multiplicative factor,was defined and used to compare the current results with the findings of studies performed in other *** findings are relevant to both human health and future environmental radiation monitoring.

关键词：放射性核种样品克什米尔河岸风险评价调查结果 226Ra gamma

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Propagation Characteristics of Acoustic Field in the Borehole Surrounded by Unconsolidated Sands

Propagation Characteristics of Acoustic Field in the Borehol...

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作者： Sonia Mohammed abdul-jabbar Mahmood（索尼娅）长安大学

学位级别：硕士

在地球物理勘探中,未固结砂岩在浅海沉积岩中比较常见。研究声波在未固结砂岩中的声波传播特征对获取未固结砂岩储层的性质具有重要意义。由于未固结砂岩与胶结好的砂岩介质不同,其颗粒之间呈弱胶结状态,其弹性模量的计算与固结砂岩不... 详细信息

在地球物理勘探中,未固结砂岩在浅海沉积岩中比较常见。研究声波在未固结砂岩中的声波传播特征对获取未固结砂岩储层的性质具有重要意义。由于未固结砂岩与胶结好的砂岩介质不同,其颗粒之间呈弱胶结状态,其弹性模量的计算与固结砂岩不同。本文对未固结砂岩的有效介质模型和理论进行了简要回顾,简要介绍了描述未固结砂岩的几种常见声场模型。针对未固结砂岩弹性模量,本文介绍了以Hertz-Mindlin模型为基础的计算未固结砂岩弹性模量的计算方法;针对未固结砂岩中的声场传播,本文介绍了以Biot-Stoll方程为基础的BICSQS模型,另外还介绍了基于颗粒介质传播频散关系的Grain-shearing(GS)理论。与此同时,本文根据Biot-Stoll方程计算了颗粒介质传播时纵横波频散曲线,并通过解析法获得了井孔声场的解析解,计算出了井中接收到的声波波形,通过数值模拟获得颗粒的弛豫性质对井孔声场传播的影响。此外,本文利用了Hertz-Mindlin模型,对井内外声场进行了数值模拟,获得不同颗粒特征对井孔声场的传播影响。

关键词：井孔声场传播 Biot-Stoll模型颗粒接触未固结砂岩

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