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Impact of urbanization on groundwater recharge and urban water balance for the city of Hyderabad, India

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International Soil and Water Conservation Research 2018年第1期6卷 51-62页

作者： Hemant Balwant Wakode Klaus Baier Ramakar Jha Rafig azzam Department of Engineering Geology and Hydrogeology RWTH Aachen UniversityLochnerstr.4-2052064 AachenGermany Department of Civil Engineering National Institute of Technology(NIT)PatnaPatnaBihar 800005India

Groundwater recharge processes in an urban area are different than in non-urban areas. There are various new components that must be considered in the case of urban groundwater recharge in addition to the natural recharge from precipitation. These various components are estimated in this study based on the water balance equation for the Hyderabad city of India. Initially, urban recharge components including leakages from water supply network and sewage networks were calculated. To estimate the natural recharge from precipitation, actual evapotranspiration and surface runoff were estimated using remote sensing and GIS techniques. Results indicated that the urban recharge component of groundwater was more than ten times greater than the natural recharge. The net urban recharge component of groundwater was estimated to be approximately 568 mm yr-1 and the natural recharge component was observed to be 53 mm yr-1. Water inflow and outflow components were also estimated to provide the complete scenario of the total urban water balance of Hyderabad. This analysis has provided the information regarding the extent and intensity of percolation of urban contaminants into the aquifer.

关键词： Groundwater recharge Urban water balance SCS Curve Number (CN) Urban recharge from leakage Hyderabad

Highly sensitive and stable SERS probes of alternately deposited Ag and Au layers on 3D SiO2 nanogrids for detection of trace mercury ions

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Chinese Physics B 2018年第7期27卷 497-506页

作者：田毅王汉夫闫兰琴张先锋 Attia falak 陈佩佩董凤良孙连峰禇卫国 CAS Key Laboratory for Nanosystems and Hierachical Fabrication Nanofabrication Laboratory CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

The hazard of Hg ion pollution triggers the motivation to explore a fast, sensitive, and reliable detection method. Here, we design and fabricate novel 36-nm-thick Ag-Au composite layers alternately deposited on three-dimensional （3D） periodic SiO2 nanogrids as surface-enhanced Raman scattering （SERS） probes. The SERS effects of the probes depend mainly on the positions and intensities of their localized surface plasmon resonance （LSPR） peaks, which is confirmed by the absorption spectra from finite-difference time-domain （FDTD） calculations. By optimizing the structure and material to maximize the intrinsic electric field enhancement based on the design method of 3D periodic SERS probes proposed, high performance of the Ag-Au/SiO2 nanogrid probes is achieved with the stability further enhanced by annealing. The optimized probes show the outstanding stability with only 4.0% SERS intensity change during 10-day storage, the excellent detection uniformity of 5.78% （RSD）, the detection limit of 5.0 × 10-12 M （1 ppt）, and superior selectivity for Hg ions. The present study renders it possible to realize the rapid and reliable detection of trace heavy metal ions by developing high- performance 3D periodic structure SERS probes by designing novel 3D structure and optimizing plasmonic material.

关键词： surface-enhanced Raman scattering Ag-Au composite layer nanostructure design trace Hg ions detection

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Imidacloprid-induced transference effect on some elements in rice plants and the brown planthopper Nilaparvata lugens （Hemiptera： Delphacidae）

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Insect Science 2011年第3期18卷 289-297页

作者： Samer azzam Fan Yang Jin-Cai Wu Jin Geng Guo-Qing Yang School of Plant Protection Yangzhou University Yangzhou Jiangsu Province China

The widespread use ofimidacloprid against insect pests has not only increased the rate of the development of target pest resistance but has also resulted in various negative effects on rice plants and Nilaparvata lugens resurgence. However, the effect of imidacloprid on elements in rice plants and the transference of these element changes between rice and N. lugens are currently poorly understood. The present study investigated changes ofCu, Fe, Mn, Zn, Ca, K, Mg and Na contents in rice plants following imidacloprid foliar sprays in the adult female ofN./ugens that develops from nymphs that feed on treated plants and honeydew produced by females. The results indicated that imidacloprid foliar spray significantly increased Fe and K contents in leaf sheaths. Generally, Fe, Mn, K and Na contents in leaf blades were noticeably decreased, but Ca contents in leaf blades for ! 0 and 30 mg/kg imidacloprid treatments were significantly increased. The contents of most elements except K and Mg in the adult females and honeydew were significantly elevated. Multivariate statistical analysis showed that Fe, Mn and Na in leaf blades and Fe and Mn in leaf sheaths could be proportionally transferred to N. lugens. The relationship between most elements in adult female bodies and in the honeydew showed a positive correlation coefficient. There were significant differences in the contents of some elements in rice plants and N. lugens from different regions.

关键词： elements imidacloprid Nilaparvata lugens rice plant transference effect

The E_iso-L_iso Plane for Gamma-Ray Bursts

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Journal of Applied Mathematics and Physics 2022年第4期10卷 1083-1088页

作者： Walid J. azzam Fatima S. Jaber Ghufran M. Ahmed Department of Physics College of Science University of Bahrain Sakhir Bahrain

Gamma-ray bursts (GRBs) are the most intense and powerful explosions in the universe. Based on their observed duration, they are traditionally divided into long bursts whose observed duration equals or exceeds 2 s, and short bursts whose observed duration is less than 2 s. Several GRB energy and luminosity correlations have been discovered for long gamma-ray bursts. Two important correlations are the Amati relation and the Yonetoku relation. The Amati relation is a correlation between the intrinsic peak energy, Ep,i, obtained from the νFν spectrum and the equivalent isotropic energy, Eiso, while the Yonetoku relation is a correlation between Ep,i and the peak isotropic luminosity, Liso. In this paper, we use a recent data sample that includes both long and short GRBs to compare these two correlations for the two groups of bursts. We also compare the Eiso-Liso plane for these two types of bursts. Our results indicate that both long and short bursts adhere to these two correlations but with different normalizations. We also find that the Eiso-Liso plane is similar for both types of GRBs but is shifted to lower values of Eiso for short GRBs.

关键词： Gamma-Ray Bursts Peak Energy Correlations Energy Indicators Luminosity Indicators

基于LiDAR技术的节理岩质边坡有限元分析

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岩石力学与工程学报 2013年第S2期32卷 3972-3978页

作者：宋杰胡辉 RAFIG azzam 德国亚琛工业大学工程地质研究所德国亚琛52064

岩质边坡的稳定性主要受其优势结构面组控制。基于地面LiDAR扫描技术和模糊聚类分析对边坡岩体出露的结构面进行自动识别和统计分组,从而获得岩体主要结构面组的几何空间信息和空间位置信息。随后通过赤平投影方法能够较好地反映出各主... 详细信息

岩质边坡的稳定性主要受其优势结构面组控制。基于地面LiDAR扫描技术和模糊聚类分析对边坡岩体出露的结构面进行自动识别和统计分组,从而获得岩体主要结构面组的几何空间信息和空间位置信息。随后通过赤平投影方法能够较好地反映出各主要结构面组与边坡的空间位置关系,确定主控边坡稳定性的优势结构面组,为数值模型的构建提供依据。最后采用有限元强度折减法求得潜在滑裂面位置和相应的安全系数。分析结果表明,岩质边坡滑裂破坏主要沿着优势结构面方向扩展,边坡下部以沿结构面的剪切破坏为主,上部以拉伸破坏为主。

关键词：边坡工程节理岩质边坡三维激光扫描模糊聚类方法赤平投影分析有限元强度折减法

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岩石黏弹塑性损伤蠕变模型及全过程研究

应用力学学报 2023年

作者：陈有亮肖鹏杜曦王苏然 Rafig azzam 上海理工大学环境与建筑学院土木工程系亚琛工业大学工程地质与水文地质系新南威尔士大学土木与环境工程学院同济大学地下建筑与工程系

准确描述岩石蠕变行为的各阶段特征对岩石力学与岩体工程的研究具有重要的意义。由于经典元件组合模型不能较好地描述岩石蠕变过程中的非线性特征，基于损伤力学理论及Kachanov蠕变损伤演化规律，将弹性体、非线性Kelvin体、线性Kelvin... 详细信息

准确描述岩石蠕变行为的各阶段特征对岩石力学与岩体工程的研究具有重要的意义。由于经典元件组合模型不能较好地描述岩石蠕变过程中的非线性特征，基于损伤力学理论及Kachanov蠕变损伤演化规律，将弹性体、非线性Kelvin体、线性Kelvin体、损伤黏弹塑性体进行串联，建立能够同时描述岩石瞬时弹性应变、非线性黏弹性应变、黏性应变和非线性黏塑性应变的非线性黏弹塑性损伤蠕变模型，采用Origin软件的Levenberg-Marquardt算法对模型参数进行了辨识，最后通过用不同应力水平下的砂岩单、三轴压缩蠕变试验对该模型的合理性进行了验证。结果表明：试验曲线和理论曲线的吻合度较高，所建模型不仅能够准确地描述岩石的瞬时弹性应变阶段、等速蠕变阶段的蠕变曲线特征，而且能够较好地描述衰减蠕变阶段和加速蠕变阶段蠕变曲线的非线性特征，验证了该模型的合理性与准确性。

关键词：岩石力学损伤非线性加速蠕变黏弹塑性蠕变模型

Single-electron pumping in a ZnO single-nanobelt quantum dot transistor

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Science China(Physics,Mechanics & Astronomy) 2020年第6期63卷 97-104页

作者： Hassan Ali Jing Tang Kai Peng SiBai Sun Attia falak FeiLong Song ShiYao Wu ChenJiang Qian Meng Wang XiTian Zhang Muhammad Aftab Rafiq XiuLai Xu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Laboratory of Quantum Engineering and Quantum Metrology School of Physics and AstronomySun Yat-Sen University(Zhuhai Campus)Zhuhai 519082China National Center for Nanoscience and Technology Chinese Academy of SciencesBeijing 100190China Department of Physics University of the PunjabQuaid-e-Azam CampusLahore 54000Pakistan Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025China Department of Physics and Applied Mathematics Pakistan Institute of Engineering and Applied SciencesIslambad 45650Pakistan CAS Center for Excellence in Topological Quantum Computation School of Physical SciencesUniversity of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

Diluted magnetic semiconductors(DMSs)have traditionally been employed to implement spin-based quantum computing and quantum information ***,their low Curie temperature is a major hurdle in their use in this field,which creates the necessity for wide bandgap DMSs operating at room *** view of this,a single-electron transistor(SET)with a global back-gate was built using a wide bandgap ZnO nanobelt(NB).Clear Coulomb oscillations were observed at 4.2 *** periodicity of the Coulomb diamonds indicates that the Coulomb oscillations arise from single quantum dots of uniform size,whereas quasi-periodic Coulomb diamonds correspond to the contribution of multi-dots present in the ZnO *** applying an AC signal to the global back-gate across a Coulomb peak with varying frequencies,single-electron pumping was observed;the increase in current was equal to the production of electron charge and *** current accuracy of about 1%for both single-and double-electron pumping was achieved at a high frequency of 25 *** accurate single-electron pumping makes the ZnO NB SET suitable for single-spin injection and detection,which has great potential for applications in quantum information technology.

关键词： ZnO nanobelt Coulomb blockade quantum dot transistor single-electron pumping

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Shear Failure Criterion and Constant Volume Ring Shear Testing Method for Clayey Soil

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Engineering（科研） 2016年第8期8卷 545-560页

作者： Rafig azzam RWTH Achen University Aachen Germany

This paper discusses the shortcomings of the traditional Coulomb shear criterion and the direct shear-box testing method used for clayey soil and presents a modified shear criterion that considers the elasto-plastic behavior of cohesive soil. This modified approach involves direct shear testing under constant volume, a method that has been developed by the author. A modified ring shear apparatus and the theory behind the shear criterion and its implication for slope stability analysis are then discussed and the results of investigated tuffitic clayey sediments are presented. The results show that the presented new shear criterion does not consider the cohesion as material constant, but rather it depends on the void ratio. In this case, the stress state and the consolidation status and thus the elasto-plastic behavior of the clayey soil are considered.

关键词： Shear Criterion Shear Testing Procedure Shear Parameter Ring Shear Testing Slope Stability Analysis

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Open Journal of Pediatrics 2022年第5期12卷 802-814页

作者： Mona Jawish Alaa Şeyhibrahim Shadia Ahmed Elsharif Bazie azzam Alabdulqader Mohammed Al Awad Yara Al Goraini Pediatric Emergency Medicine Security Forces Hospital Riyadh Saudi Arabia Collage of Medicine Alfaisal University Riyadh Saudi Arabia Pediatric Medicne King Faisal Specialist Hospital and Research Center Riyadh Saudi Arabia College of Medicine King Saud Bin Abdul-Aziz University for Health and Sciences Riyadh Saudi Arabia Pediatric Emergency Medicine King Fahad Medical City Riyadh Saudi Arabia

Introduction: We report an eight-case series of coronavirus disease 2019 (COVID-19)-related multisystem inflammatory syndrome in children (MIS-C). Methods: Children who tested positive for COVID-19, met the MIS-C criteria of the World Health Organization (WHO), and were hospitalized at a tertiary hospital in Riyadh from September to December 2021 were identified and their clinical data reviewed. Results: The age at diagnosis is between 4 to 13 years old. Fever, decreased oral intake, gastroenteritis, and abdominal pain were the most common symptoms. All cases showed hyperinflammation with high C-reactive protein, erythrocyte sedimentation rate, ferritin levels, and deranged coagulation profiles. Most of the cases had elevated B-type natriuretic peptide (75%) and troponin (100%) levels. However, two cases had cardiovascular involvement. Two patients presented with acute respiratory distress syndrome and required mechanical ventilation. The mean hospital stay was 13.1 days, with seven patients initially requiring intensive care management for ionotropic support. Most cases required broad-spectrum antibiotics, intravenous steroids, intravenous immunoglobulin, and aspirin. All patients recovered and were discharged from the hospital in good clinical condition. Conclusion: Children with COVID-19 are at risk of developing MIS-C. Practitioners must have a high index of suspicion for its diagnosis and should start treatment as soon as possible to prevent unfavorable outcomes.

关键词： COVID-19 MIS-C SARS-Cov2 Pediatric Emergency