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American Journal of Plant Sciences 2015年第9期6卷 1361-1369页

作者： muhammad Mahran aslam muhammad Zeeshan Ayesha Irum muhammad Umair Hassan Saif Ali Rashid Hussain Pia muhammad Adnan Ramzani muhammad Farhan Rashid Department of Plant Breeding and Genetics University of Agriculture Faisalabad Pakistan Department of Agronomy University of Agriculture Faisalabad Pakistan Institute of Soil and Environmental Science University of Agriculture Faisalabad Pakistan Institute of Horticultural Sciences University of Agriculture Faisalabad Pakistan

Rice is an important crop and the food security of the world is strongly associated with it as it is the staple food of half of the world’s population. Among various agro-management practices seedling age and nitrogen rates significantly affected its growth, development and yield components. Rice cultivars performed differently when transplanted in field at varying seedling ages depending upon their genetic makeup and adoptability to certain environmental conditions. Seedling age plays an important role in yield contributing parameters like number of productive tillers, panicle length, filled grains panicle-1 and 1000-kernel weight leading to higher paddy yield in different rice cultivars and hybrids. Nitrogen is required in huge quantity in rice production as it is an important constituent of plant parts and processes. Paddy yield increases significantly with the increase in nitrogen rate but after a certain limit yield starts decreasing. Keeping in view the significance of seedling age and nitrogen rates in different rice cultivars and hybrids, an effort has been made to review some research work already conducted and will be helpful to the researchers and scientists to plan future strategies.

关键词： Hybrid Rice Seedling Age Nitrogen Rates Paddy Yield

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软弱泥质砂岩地层中输水隧洞稳定性研究

岩土力学 2022年第S2期43卷 626-639页

作者： muhammad usman Azhar 周辉杨凡杰高阳朱勇路新景房后国耿轶君中国科学院武汉岩土力学研究所岩土力学和工程国家重点实验室湖北武汉430071 中国科学院大学北京100049 黄河工程咨询有限公司河南郑州450003

泥质砂岩属于黏土岩,具有典型的遇水软化特征。在泥质砂岩富水地层中进行隧道开挖是地下工程的一个挑战性问题。研究了围岩软化与未软化条件下泥质砂岩地层中输水隧洞的稳定性和支护时间。首先,介绍了泥质砂岩遇水软化的力学试验结果;然... 详细信息

泥质砂岩属于黏土岩,具有典型的遇水软化特征。在泥质砂岩富水地层中进行隧道开挖是地下工程的一个挑战性问题。研究了围岩软化与未软化条件下泥质砂岩地层中输水隧洞的稳定性和支护时间。首先,介绍了泥质砂岩遇水软化的力学试验结果;然后,采用基于Hoek-Brown强度准则的岩体参数评价方法,评估泥质砂岩在围岩软化与未软化条件下的力学参数;再后,以兰州水源地引水隧洞为依托工程,采用数值模拟方法对泥质砂岩隧洞软化与未软化工况的围岩稳定性进行了计算分析,得出泥质砂岩遇水软化对隧洞安全性存在显著影响;最后,采用位移收敛法,研究了泥质砂岩软化与未软化工况中,保障隧洞施工安全的合理支护时机。研究表明,泥质砂岩未软化工况中,可考虑隧道围岩初期支护在距掌子面4~5m位置实施;而在泥质砂岩遇水软化工况中,初期支护建议在掌子面开挖后立刻支护。研究成果可为泥质砂岩地层隧洞的安全施工提供依据。

关键词：泥质砂岩遇水软化隧洞稳定性数值分析收敛约束法支护时机

Role of Canal Lining on Groundwater Fluctuations: A Modeling Simulation Approach for Jaalwala Distributary, Bahawalnagar

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Open Journal of Applied Sciences 2017年第5期7卷 213-232页

作者： muhammad Hammad Atique Khan muhammad usman Saleem Sajid Rashid Ahmad Nasir Ahmad Shahid Jamil Sameeni muhammad Akram muhammad Farooq Institute of Geology University of the Punjab Lahore Pakistan Collage of Earth and Environmental Sciences University of the Punjab Lahore Pakistan Irrigation Department Government of Pakistan Lahore Pakistan

Jaalwala Distributary was selected to see the consequences of concrete lining on the underlying saline groundwater table. Its middle and tail portions were concrete lined whereas the head portion was still unlined. Visual MODFLOW 2011.1 was used to simulate the effects of concrete lining on saline groundwater in two-dimensional format. Simulation results showed a gradual rise of electrical conductivity (EC) up to 7000 μS/cm and decline in water table depth to nine feet (2.74 m). It observed negligible inflows from the distributary through its western boundary due to formation of a permanent barrier in the way of seepage of any kind. Results have further predicted that freshwater layer available beneath the Jaalwala Distributary (before its lining) will finish ultimately and the below present saline water also move upward to take this vacated place. Hence it was concluded to line the canals of saline water areas from their sides which will not only protect them from erosion but canal water theft as well.

关键词： Water Balance Jaalwala Distributary Saline Water Intrusion Hydrostatic Pressure and Interface

Study on the synthesis of spin labeled poly(styrene-co-maleic acid)s and their segmental motion

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Magnetic Resonance Letters 2022年第2期2卷 80-90,I0002页

作者： Kaleem-Ur-Rahman Naveed Li Wang Haojie Yu Qian Zhang Wei Xiong Raja Summe Ullah Ahsan Nazir muhammad usman Shah Fahad Amin Khan Md Alim Uddin Di Shen State Key Laboratory of Chemical Engineering College of Chemical&Biological EngineeringZhejiang UniversityHangzhou310027China The First Affiliated Hospital College of MedicineZhejiang UniversityHangzhou310003China

Study of the segmental mobility of polymer chains is important when the polymer is used as drag reduction agents of crude *** spin resonance(ESR)spectroscopy can provide important information about segmental dynamics of polymer chains,which is related to their *** this article,we employed an amphiphilic polymer to study the effect of hydrophilic/hydrophobic balance of the polymers on the segmental motion of polymer ***(styrene-co-maleic acid)(PSMA)was spin labeled with 4-amino TEMPO radicals by increasing the concentration of radical moiety on the polymer *** PSMA and spin labeled-PSMAs(SL-PSMAs)were characterized by nuclear magnetic resonance(NMR),Fourier transform infrared(FT-IR)spectroscopy,Cyclic voltammetry(CV)and ESR ***-polymer complexes(IPCs)of SL-PSMA-2 were prepared by employing polyethylene glycols(PEGs)of varying molecular *** results showed that the increased hydrophobic interactions of nitroxide radicals on the SLPSMAs’chains reduced the rotational mobility of spin labels and the random coil-toglobular transition of polymer chains occurred at higher pH value for SL-PSMAs,which showed a slow motion component in the ESR spectra of ***,by increasing the molecular weight of PEGs in IPCs the complexation was increased,which also reduced the rotational motion of spin labels due to interpolymer hydrogen bonding causing a slow motion component in the ESR spectra.©2021 The Authors.

关键词： Electron spin resonance(ESR) Spin labeling Nitroxide radicals poly(styrene-co-maleic acid)s Segmental motion

Bifunctional catalysts of Co3O4@GCN tubular nanostructured （TNS） hybrids for oxygen and hydrogen evolution reactions

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Nano Research 2015年第11期8卷 3725-3736页

作者： muhammad Tahir Nasir Mahmood Xiaoxue Zhang Tariq Mahmood Faheem. K. Butt Imran aslam M.Tanveer Faryal Idrees Syed Khalid Imran Shakir Yiming Yan Jijun Zou Chuanbao Cao Yanglong Hou Research Centre of Materials Science Beijing Institute of Technology Beijing 100081 China Department of Materials Science and Engineering Peldng University Beijing 100081 China Beijing Key Laboratory for Chemical Power Source and Green Catalyst School of Chemical Engineering and Environment Beijing Institution of Technology Beijing 100081 China Sustainable Energy Technologies (SET) center building No 3 Room 1c23 College of Engineering King Saud University PO BOX 800 Riyadh 11421 Kingdom of Saudi Arabia Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and Technology Tianjin University Collaborative Innovative Center of Chemical Science and Engineering (Tianjin) Tianjin 300072 China

Catalysts for oxygen and hydrogen evolution reactions （OER/HER） are at the heart of renewable green energy sources such as water splitting. Although incredible efforts have been made to develop efficient catalysts for OER and HER, great challenges still remain in the development of bifunctional catalysts. Here, we report a novel hybrid of Co3O4 embedded in tubular nanostructures of graphitic carbon nitride （GCN） and synthesized through a facile, large-scale chemical method at low temperature. Strong synergistic effects between Co3O4 and GCN resulted in excellent performance as a bifunctional catalyst for OER and HER. The high surface area, unique tubular nanostructure, and composition of the hybrid made all redox sites easily available for catalysis and provided faster ionic and electronic conduction. The Co3O4@GCN tubular nanostructured （TNS） hybrid exhibited the lowest overpotential （0.12 V） and excellent current density （147 mA/cm^2） in OER, better than benchmarks IrO2 and RuO2, and with superior durability in alkaline media. Furthermore, the Co3O4@GCN TNS hybrid demonstrated excellent performance in HER, with a much lower onset and overpotential, and a stable current density. It is expected that the Co3O4@GCN TNS hybrid developed in this study will be an attractive alternative to noble metals catalysts in large scale water splitting and fuel cells.

关键词： carbon nitride cobalt oxide bifunctional catalyst oxygen evolution reaction hydrogen evolution reaction

Accurate Imputation for Relative Humidity over Pakistan Gathered from AQUA Satellite

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Open Journal of Geology 2018年第10期8卷 987-1001页

作者： usman Saleem Mian Sohail Akram muhammad Fahad Ullah Faisal Rehman Institute of Geology University of the Punjab Lahore Pakistan Departments of Earth Sciences University of Sargodha Sargodha Pakistan

The relative humidity in the atmosphere captured by AQUA satellite contains missing matrices. In order to fill such missing values four very popular imputation techniques: Bilinear, Inverse Distance Weighting, Natural Neighbor and Nearest Interpolations were tested. Mean Absolute Error (MAE), Root Mean Square Error (RMSE), Coefficient of Determination (R2) and Correlation Coefficient (Corr), were used to check the accuracy of these interpolations. It was found that the Inverse Distance Weighting and Nearest Interpolation were proved not to be suited. Natural interpolation gave accurate results than the aforementioned two interpolations. Missing values of relative humidity were accurately refilled with Bilinear Interpolation. This interpolation produced RMSE of ±0.543 for relative humidity over 100, 150, 200, 250, 300, 400, 500 hPa while for 600, 700, 850 and 925 hPa RMSE remainnear to 1. A perfect fit to the surface and very strong correlation (value near to 0.99) was found between actual and imputed relative humidity data through Bilinear Interpolation. Therefore it was concluded that the Bilinear Interpolation is the most accurate and best imputation for missing values of relative humidity form 100 to 1000 hPa levels.

关键词： Imputation Humidity Aqua Satellite Pakistan

Evaluation and comparison of CMIP6 models and MERRA-2 reanalysis AOD against Satellite observations from 2000 to 2014 over China

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Geoscience Frontiers 2022年第2期13卷 165-185页

作者： Md.Arfan Ali muhammad Bilal Yu Wang Zhongfeng Qiu Janet E.Nichol Gerrit de Leeuw Song Ke Alaa M.hawish Mansour Almazroui usman Mazhar Birhanu Asmerom Habtemicheal M.Nazrul Islam Lab of Environmental Remote Sensing(LERS) School of Marine SciencesNanjing University of Information Science and TechnologyNanjing 210044China Department of Geography School of Global StudiesUniversity of SussexBrighton BN19RHUK Royal Netherlands Meteorological Institute(KNMI) R&D Satellite Observations3730AE De BiltThe Netherlands School of Atmospheric Physics Nanjing University of Information Science and TechnologyNanjing 210044China Aerospace Information Research Institute Chinese Academy of Sciences(AirCAS)No.20 Datun RoadChaoyang DistrictBeijing 100101China School of Environment Science and Spatial Informatics University of Mining and TechnologyXuzhouJiangsu 221116China Geological Survey of Jiangsu Province Nanjing 210018China Center of Excellence for Climate Change Research/Department of Meteorology King Abdulaziz UniversityJeddah 21589Saudi Arabia Climatic Research Unit School of Environmental SciencesUniversity of East AngliaNorwichUK School of Remote Sensing and Geomatics Engineering Nanjing University of Information Science and TechnologyNanjing 210044China Department of Physics Wollo UniversityDessie P.O.Box 1145Ethiopia

Rapid industrialization and urbanization along with a growing population are contributing significantly to air pollution in *** of long-term aerosol optical depth(AOD)data from models and reanalysis,can greatly promote understanding of spatiotemporal variations in air pollution in *** do this,AOD(550 nm)values from 2000 to 2014 were obtained from the Coupled Model Intercomparison Project(CIMP6),the second version of Modern-Era Retrospective analysis for Research,and Applications(MERRA-2),and the Moderate Resolution Imaging Spectroradiometer(MODIS;flying on the Terra satellite)combined Dark Target and Deep Blue(DTB)aerosol *** used the TerraMODIS DTB AOD(hereafter MODIS DTB AOD)as a standard to evaluate CMIP6 Ensemble AOD(hereafter CMIP6 AOD)and MERRA-2 reanalysis AOD(hereafter MERRA-2 AOD).Results show better correlations and smaller errors between MERRA-2 and MODIS DTB AOD,than between CMIP6 and MODIS DTB AOD,in most regions of China,at both annual and seasonal ***,significant under-and over-estimations in the MERRA-2 and CMIP6 AOD were also observed relative to MODIS DTB *** long-term(2000-2014)MODIS DTB AOD distributions show the highest AOD over the North China Plain(0.71)followed by Central China(0.69),Yangtse River Delta(0.67),Sichuan Basin(0.64),and Pearl River Delta(0.54)*** lowest AOD values were recorded over the Tibetan Plateau(0.13±0.01)followed by Qinghai(0.19±0.03)and the Gobi Desert(0.21±0.03).Large amounts of sand and dust particles emitted from natural sources(the Taklamakan and Gobi Deserts)may result in higher AOD in spring compared to summer,autumn,and *** were also calculated for 2000-2005,for2006-2010(when China introduced strict air pollution control policies during the 11 th Five Year Plan or FYP),and for 2011-2014(during the 12 th FYP).An increasing trend in MODIS DTB AOD was observed throughout the country during *** uncontrolled industrialization,urbanization,and rapid eco

关键词： Aerosol Optical Depth Air pollution MERRA-2 MODIS Air quality

Weed Control Practices and Varying Sowing Dates Effects on Seed Production of Pearl Millet (<i>Pennisetum americanum</i>L.) under Semi-Arid Environment

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American Journal of Plant Sciences 2018年第9期9卷 1974-1986页

作者： Naveed Arslan usman Zulfiqar muhammad Ishfaq muhammad Ahmad muhammad Nabeel Anwar Azeem Ullah Iqra Nazar Asif Iqbal muhammad Zohaib Anjum Department of Agronomy University of Agriculture Faisalabad Pakistan Department of Botany University of Agriculture Faisalabad Pakistan Department of Forestry and Range Management University of Agriculture Faisalabad Pakistan

Peral millet being drought tolerant has substantial potential to contribute in food security ensuring the food, fodder and nutritional value in different Asian and African countries. Susceptibility to abiotic and biotic factors and low productivity are the main reasons for decreasing productivity and area of millets. In this context, evaluation of the effect of weed control practices and varying sowing dates on grain yield of kharif season grown pearl millet (Pennisetum americanum L.) was demonstrated at post graduate agriculture research station, University of Agriculture, Faisalabad during 2015. Forage pearl millet was sown at three different sowing dates i.e. mid-June, end of June and mid-July and four weed control practices viz. weedy check (no weeding), twice hoeing at 15 and 30 days after sowing (DAS), weed control using herbicides i.e. application of Atrazine (Awax 38 SC) @330 g a.i. ha-1 at 15 DAS, and twice foliar applications of 10% Sorghum water extract (Sorgaab) (at 15 and 30 DAS). The experiment was laid out in randomized complete block design (RCBD) under split plot arrangement, comprising of three replications. The treatments with varying sowing dates were randomized in main plots and weed control practices were in subplots. Results showed that the highest plant height (279.51 cm), leaf area (2777.80 cm2), fresh weight of leaves per plant (155.57 g), maximum number of grains per head (3162.0) and grain yield (3419.7 kg·ha-1) were obtained in the treatment combination of 30th June sowing × twice weed hoeing (at 15 and 30 DAS) while, maximum 1000-grain weight (8.45 g) was observed in treatments where weeds were controlled by hoeing (at 15 and 30 DAS). Moreover, cultural weed control practices reduce significantly weed density, fresh and dry Wight of weeds. In sum, it is concluded that to reduce the weed-crop competition and to gain higher productivity of pearl millet, field should be weed free 20 - 45 days after sowing.

关键词： Sowing Dates Weed Control Methods Herbicide Grain Yield Pearl Millet

Fournier's Gangrene: Experience with Management of 46 Cases in a Tertiary Institution

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Open Journal of Urology 2012年第3期2卷 109-112页

作者： Sani Ali Aji Sani usman Alhassan Musa muhammad Ujudud Urology Unit Department of Surgery Aminu Kano Teaching Hospital Kano Nigeria

Background: Fournier's gangrene is a rapidly spreading necrotizing gangrene affecting the perineum, Perianal and genital regions but remarkably sparing the testicles, bladder and rectum due to their separate blood supply which is directly from the aorta. The aim of this study is to share our experience with the management of 46 cases. Patients and method: We retrospectively analysed the medical records of 46 patients admitted with Fournier's gangrene between April 2005 and December 2011 in the urology unit of Aminu Kano Teaching Hospital. Data extracted from these include age, sex, hospital stay, premorbid diseases, mobility, mortality, laboratory investigations and treatments carried out. Results: Fourty six patients were admitted and managed for Fournier's gangrene during the study period. All the patients were male and mean age was 50 years (range 20 - 80 years). Five patients died (10.90%) mortality, 41 (89.10%) patients survived. The shortest hospital stay was 13 days and longest was 120 days. 45.7% of the patients had urethral stricture with watering can perineum as predisposing factor, 16 (34.80%) had diabetes mellitus, 7 (15.2%) had perineal injuries as the predisposing factors while 5 (10.90%) patients had uraemia and one patient (2.20%) each had bladder tumour and scrotal abscess as their predisposing factors, in 3 patients (6.50%) it was idiopathic. Only 34 (73.90%) patients had wound swab microscopy culture and sensitivity on admission. The culture grew Klebsiella spp. in 9 (26.50%), Staph aureus and E. coli in 5 (10.90%) of cases each, while Gram positive rod and Gram negative Cocci with 4 (11.80%) and 6 (17.60%) respectively. Conclusion: Fournier's gangrene which is a rapidly progressive, fulminant polymicrobial synergistic infection of the perineum and genitals, is now changing pattern. Extensive surgical debridement and broad spectrum intravenous antibiotics remain the mainstay of treatment.

关键词： Fournier's Gangrene Management Changing Pattern