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

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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

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

Morphological and electrical properties of SrTiO3/TiO2/SrTiO3 sandwich structures prepared by plasma sputtering

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Chinese Physics B 2017年第1期26卷 156-159页

作者： Saqib jabbar Riaz Ahmad Paul K Chu Government College University Lahore 54000 Pakistan Department of Physics and Materials Science City University of Hong Kong Kowloon Hong Kong China

SrTiO3（STO） and TiO2 are insulating materials with large dielectric constants and opposite signs of the quadratic coefficient of voltage（α）. Insertion of a TiO2 thin film between STO layers increases the linearity of the capacitance in response to an applied voltage, to meet the increasing demand of large-capacitance-density dynamic random access memory capacitors. Both STO and TiO2 suffer from the problem of high leakage current owing to their almost equivalent and low bandgap energies. To overcome this, the thickness of the thin TiO2 film sandwiched between the STO films was varied. A magnetron sputtering system equipped with radio frequency and direct current power supply was employed for depositing the thin films. Ti N was deposited as the top and bottom metal electrodes to form a metal–insulator metal（MIM） structure,which exhibited a very large linear capacitance density of 21 fF/um-2 that decreased by increasing the thickness of the TiO2 film. The leakage current decreased with an increase in the thickness of TiO2, and for a 27-nm-thick film, the measured leakage current was 2.0 × 10^-10 A. X-ray diffraction and Raman spectroscopy revealed that Ti N, STO, and TiO2 films are crystalline and TiO2 has a dominant anatese phase structure.

关键词： strontium titanate Raman spectroscopy plasma deposition MIM capacitor

Assessment of Soil Salinity Risk on the Agricultural Area in Basrah Province,Iraq:Using Remote Sensing and GIS Techniques

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Journal of Earth Science 2012年第6期23卷 881-891页

作者： Mushtak T jabbar 周敬宣 School of Environmental Science&Engineering Huazhong University of Science&Technology Department of Soil and Water College of AgricultureUniversity of Basrah

This study presents an integrated study of expansion process of salinized land in Basrah Province, a typical salt-affected area in southern parts of Iraq, by using geo-information techniques. Satellite images （Landsat TM 1990） and thematic maps （ETM 2003） were used to provide comprehen- sive views of surface conditions such as vegetation cover and salinization detection. With ERDAS soft- ware, the normalized differential salinity index （NDSI） and salinity index （SI） were computed and then evaluated for soil degradation by salinization. ARC/INFO software was used along with field observa- tion data （global positioning system） for analysis. During the past 13 years, the salinized land in study area increased by 6 579.1 km2 and in 2003 covered 34.5% of the total area; in the meantime, vegetation cover has decreased by 4 595.9 km2 and in 2003 covers only 24.1% of the study area. Environmental changes show that, between 1990 and 2003, 37.5% of vegetation cover and 45.9% of marshlands were transformed into salty meadow and wet salty crust, respectively. In addition, there was 16.6% of sand lands converted into dry puffy salty crust. Results using spatial analysis methods showed that 7 894.9 km2 （41.4%） of land had no risk of environment degradation by soil salinity, 4 595.9 km2 （24.1%） bad slight risk, 4 042.8 km2 （21.2%） had moderate risk, and 2 536.3 km2 （13.3%） of the total land area was at a high risk of environment degradation by soil salinity. In conclusion, the study area was ex- posed to a high risk of soil salinity.

关键词： environmental degradation soilsalinity risk remote sensing GIS Iraq.

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

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

Remote Sensing and GIS Application in the Detection of Environmental Degradation Indicators

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Geo-Spatial Information Science 2011年第1期14卷 39-47页

作者： HadeelA S Mushtak T jabbar CHEN Xiaoling State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University 129 Luoyu Road Wuhan 430079. China Department of Soil and Water College of Agriculture University of Basrah (Iraq) Key Laboratory of Poyang Lake Wetland and Watershed Research Ministry of Education Jiangxi Normal UniversityNanchang 330022. China

The main aim of this research is to highlight the environment change indicators during the last 20 years in a representative area of the southern part of Iraq （Basrah Province was taken as a case） to understand the main causes which led to widespread environment degradation phenomena using a 1：250000 mapping scale. Remote sensing and GIS＇s software were used to classify Landsat TM in 1990 and Landsat ETM＋ in 2003 imagery into five land use and land cover （LULC） classes： vegetation land, sand land, urban area, unused land, and water bodies. Supervised classification and Normalized Difference Vegetation Index （NDVI）, Normalized Difference Build-up Index （NDBI）, Normalized Difference Water Index （NDWI）, Normalized Difference Salinity Index （NDSI）, and Topsoil Grain Size Index （GSI） were adopted in this research and used respectively to retrieve its class boundary. The results showed a clear deterioration in vegetative cover （514.9 km2） and an increase of sand dune accumulations （438.6 km2）, accounting for 10.1, and 10.6 percent, respectively, of the total study area. In addition, a decrease in the water bodies＇ area was detected （228.9 kin2）. Sand area accumulations had increased in the total study area, with an annual increasing expansion rate of （33.7 km2 · yr^-1） during the thirteen years covered by the study. It is therefore imperative that Iraqi government undertake a series of prudent actions now that will enable to be in the best possible position when the current environmental crisis ultimately passes.

关键词： environment degradation LULC RS GIS classification indices

Application of GIS to Estimate Soil Erosion Using RUSLE

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Geo-Spatial Information Science 2003年第1期6卷 34-37页

作者： Mushtak Talib jabbar Institue of Mathe matical Geology & RemoteSensing

This paper describes the use of the Arc/Info and ArcView GIS tools to estimate soil erosion with Universal Soil Loss Equation (USLE).Calculations are be done by using capabilities *** study start with a digital elevation model (DEM) of Shaanxi,which was created by digitizing contour and spot heights from the topographic map on 1∶250 000 scale and grid themes for the USLE K and C *** is note worthy that USLE K can be obtained by adding the K factor as an attribute to a soil theme’s *** C can be obtained from tables or using the information about land use and management given by USLE program.A land use theme can be used to add the C factors as an attribute *** purpose of this study is to establish spatial information of soil erosion using USLE and GIS and discuss the analysis of the soil erosion and slope failures in GIS and formulate the possible framework.

关键词： soil erosion USLE DEM GIS

Using Remote Sensing and GIS Techniques to Study Soil Degradation Processes in North Shaanxi Province,China

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Journal of China University of Geosciences 2003年第4期14卷 356-362页

作者： Mushtak Talib jabbar Faculty of Earth Resources China University of Geosciences

Satellite image data and thematic map data were used to provide comprehensive views of surface-bound conditions such as soil and vegetation degradation. The current work applies a computerized parametric methodology, developed by FAO, UNEP and UNESCO to assess and evaluate soil degradation at 1∶250 000 mapping scale. The study area is located in the arid and semi-arid zone of the northern part of Shaanxi Province in China, a region with considerable agricultural potential; Landsat TM images were utilized to provide recent data on land cover and use of the area. ARC/INFO and ArcView softwares were used to manage and manipulate thematic data, to process satellite images, and tabular data source. ER mapper software is utilized to derive the normalized difference vegetation index (ND VI) values while field data to estimate soil erodibility ( SE ) factor. A system is established for rating soil parameters, slope, climate factor and human factor activity. The rating values serve as inputs into a modified universal soil loss equation (USLE) to calculate the present state and risk for soil degradation processes, namely soil wind erosion. The produced maps and tabular data show the risk and the present status of different soil degradation processes. The study area, in general, is exposed to high risk of wind erosion and high hazards of water erosion. Several desertification maps were produced, which reflect the desertification types persisting in the study area. Wind erosion, water erosion, vegetation degradation, physical degradation and salinization are the basic desertification maps, and others are combinations of these basic maps. In terms of statistic analysis, 33.75 % of the total land area (120.330 0 ha) is considered as sand or sand dune, and not included in our analysis of desertification. About 29.41 % of the total land area has slight or moderate desertification and 37.465 % is facing severe desertification.

关键词： soil degradation desertification GIS remote sensing China.