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Synthesis of yttrium and cerium doped ZnO nanoparticles as highly inexpensive and stable photocatalysts for hydrogen evolution

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Journal of Rare Earths 2021年第4期39卷 440-445页

作者： Irshad Ahmad m.ham.ad shoaib Akhtar mian Faisal manzoor m.ham.ad Wajid m.ham.ad Noman Ejaz Ahmed mukhtar Ahmad Waheed Qamar Khan Anwar m.Rana Department of Physics.Bahauddin Zakariya University Multan60800Pakistan School of Computer and Communication Lanzhou University of Technology.Lanzhou730050China Department of Physics University of Agriculture Faisalabad38040Pakistan Institute of advanced materials Bahauddin Zakariya UniversityMultan6800Pakistan

Yttrium and cerium co-doped ZnO nanoparticles were synthesized by combustion route and characterized using X-ray diffraction(XRD),scanning electron microscopy(SEm),Brunauer-Emmett-Teller(BET),energy dispersive spectroscopy(EDS),X-ray photoelectron spectroscopy(XPS),UV-visible diffuse reflectance spectroscopy(UV-vis DRS),photoluminescence(PL)and electrochemical impedance spectroscopy(EIS)*** introduction of yttrium ions has efficiently increased the relative percentage of Ce^(3+)ions in *** and cerium co-doped ZnO shows efficient photo activity for hydrogen evolution(10.61 mmol/((g·h))higher than previously reported optimal value for rare earth codoped ZnO *** remarkably increased hydrogen evolution can be ascribed to the synergy between electronic anchoring effect of Y^(3+)/Y^(2+)and Ce^(4+)/Ce^(3+)redox *** report presents new idea for the synthesis of efficient photocatalyst using economical route and ion anchoring *** hydrogen evolution was also tested using Na_(2)S and Na_(2)SO_(3)as electron donors under visible light *** synthesized photocatalysts also exhibit high stability.

关键词： ZnO H_(2)evolution Na_(2)SO_(3) PL Stability Rare earths

Exploring Crowdsourced Hard—Acceleration and Braking Event Data for Evaluating Safety Performance of Low-Volume Rural Highways in Iowa

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Journal of Transportation Technologies 2023年第2期13卷 282-300页

作者： shoaib mahmud Christopher m. Day Department of Civil Construction and Environmental Engineering Iowa State University Ames USA

There are over four million miles of two-lane roadways across the United States, of which a substantial portion is low-volume roads (LVR). Traditionally, most traffic safety efforts and countermeasures focus on high-volume high-crash urban locations. This is because LVRs cover an extensive area, and the rarity of crashes makes it challenging to use crash data to monitor the safety performance of LVRs regularly. In addition, obtaining up-to-date roadway information, such as pavement or shoulder conditions of an extensive LVR network, can be exceptionally difficult. In recent times, crowdsourced hard-acceleration and braking event data have become commercially available, which can provide precise geolocation information and can be readily acquired from different vendors. The present paper examines the potential use of this data to identify opportunities to monitor the safety of LVRs. This research examined approximately 12 million hard-acceleration and hard-braking events over a 3-months period and 26,743 crashes, including 9373 fatal injuries over the past 5-year period. The study found a moderate correlation between hard acceleration/hard-braking events with historical crash events. This study conducted a hot spot analysis using hard-acceleration/hard-braking and crash datasets. Hotspot analysis detected spatial clusters of high-risk crash locations and detected 848 common high-risk sites. Finally, this paper proposes a combined ranking scheme that simultaneously considers historical crash events and hard-acceleration/hard-braking events. The research concludes by suggesting that agencies can potentially use the hard-acceleration and hard-braking event dataset along with the historical crash dataset to effectively supervise the safety performance of the vast network of LVRs more frequently.

关键词： Connected Vehicle Low Volume Highway High-Risk Crash Sites Hard Acceleration and Braking Events Geographic Information System

Comparative study of Sm^(3+) ions doped phosphate based oxide and oxy-fluoride glasses for solid state lighting applications

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Journal of Rare Earths 2019年第4期37卷 374-382页

作者： m.shoaib G.Rooh R.Rajaramakrishna N.Chanthima N.Kiwsakunkran H.J.Kim J.Kaewkhao S.Tuscharoen Department of Physics Abdul Wali Khan University Center of Excellence in Class Technology and materials Science (CEGm) Nakhon Pathom Rajabhat University Physics Program Faculty of Science and TechnologyNakhon Pathom Rajabhat University Department of Physics Kyungpook National University

The physical and luminescent properties of Sm^(3+)-doped oxide and oxy-fluoride phosphate glasses were investigated. The glass samples with chemical composition of 69 P_2 O_5-10 BaO-10 ZnO-10 Gd_2 O_3-1 Sm_2 O_3 and 69 P_2 O_5-10 BaO-10 ZnO-10 GdF_3-1 Sm_2 O_3 were prepared by conventional melt quenching technique. The prepared glass samples were characterized with density, molar volume, refractive index,FTIR, UV-Vis-NIR, photo luminesce nce, radio luminescence, decay time profile and CIE diagram. The density and refractive index of the oxide glass have higher values as compared to the oxy-fluoride *** FTIR spectra show the reduction of O-H group in oxy-fluoride glass. The characteristic peaks of Sm^(3+)are observed at 360,372,402,438,419,473,944,1077,1227,1373,1474,1529 and 1585 nm in UV-VIS-NIR spectra. These peaks are related respectively to the transitions from ground state ~6 H_(5/2) to ~4 D_(3/2), ~6 P_(7/2),6 P3/2, ~4 I_(11/2), ~6 F_(11/2), ~6 F_(9/2), ~6 F_(7/2),~6 F_(5/2),~6 F_(3/2), ~6 H_(15/2) and ~6 F_(1/2) excited states. From photoluminescence and radio-luminesce nce it is observed that the oxy-fluoride glass samples show better emission intensity than the oxide glass. The Judd-Ofelt theory(J-0 theory) was used to find J-O intensity Ω_λ(λ = 2,4 and 6)parameters and radiative properties such as transition probability, stimulated emission cross section and branching ratios for titled glasses. The trend observed in the J-O parameters is Ω_4 >Ω_2 >Ω_6. The transition probability,emission cross section and branching ratio have the highest values for the ~4 G_(5/2)→~6 H_(7/2)transition. The CIE coordinates of the prepared glass samples are positioned in the orange region and the CCT value is 3776.105 for oxide and oxyfluoride glass. The oxy-fluoride glass has shorter decay time as compared to the oxide glass and it is recorded to be 1.62 and 1.32 ms for oxide and oxy-fluoride respectively. According to the results obtained in this work, it is obvious t

关键词： Oxy-fluoride glass Photoluminescence Judd-Ofelt theory CIE coordinates Rare earths

Evaluation of Arterial Signal Coordination with Commercial Connected Vehicle Data: Empirical Traffic Flow Visualization and Performance measurement

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Journal of Transportation Technologies 2023年第3期13卷 327-352页

作者： shoaib mahmud Christopher m. Day Department of Civil Construction and Environmental Engineering Iowa State University Ames USA

Emerging connected vehicle (CV) data sets have recently become commercially available, enabling analysts to develop a variety of powerful performance measures without deploying any field infrastructure. This paper presents several tools using CV data to evaluate traffic progression quality along a signalized corridor. These include both performance measures for high-level analysis as well as visualizations to examine details of the coordinated operation. With the use of CV data, it is possible to assess not only the movement of traffic on the corridor but also to consider its origin-destination (O-D) path through the corridor. Results for the real-world operation of an eight-intersection signalized arterial are presented. A series of high-level performance measures are used to evaluate overall performance by time of day, with differing results by metric. Next, the details of the operation are examined with the use of two visualization tools: a cyclic time-space diagram (TSD) and an empirical platoon progression diagram (PPD). Comparing flow visualizations developed with different included O-D paths reveals several features, such as the presence of secondary and tertiary platoons on certain sections that cannot be seen when only end-to-end journeys are included. In addition, speed heat maps are generated, providing both speed performance along the corridor and locations and the extent of the queue. The proposed visualization tools portray the corridor’s performance holistically instead of combining individual signal performance metrics. The techniques exhibited in this study are compelling for identifying locations where engineering solutions such as access management or timing plan change are required. The recent progress in infrastructure-free sensing technology has significantly increased the scope of CV data-based traffic management systems, enhancing the significance of this study. The study demonstrates the utility of CV trajectory data for obtaining high-level

关键词： Traffic Signal Performance measures Vehicle Trajectory Data Connected Vehicle Data

A Novel Inherited modeling Structure of Automatic Brain Tumor Segmentation from mRI

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Computers, materials & Continua 2022年第11期73卷 3983-4002页

作者： Abdullah AAsiri Tariq Ali Ahmad Shaf m.ham.ad Aamir m.ham.ad shoaib m.ham.ad Irfan Hassan A.Alshamrani Fawaz F.Alqahtani Osama m.Alshehri Radiological Sciences Department College of Applied Medical SciencesNajran UniversityNajran61441Saudi Arabia Department of Computer Science COMSATS University IslamabadSahiwal CampusSahiwal57000Pakistan Department of Informatics and Systems University of Management and TechnologyLahore54000Pakistan Electrical Engineering Department College of EngineeringNajran UniversityNajran61441Saudi Arabia Department of Clinical Laboratory Sciences Collage of Applied Medical ScienceNajran UniversityNajranSaudi Arabia

Brain tumor is one of the most dreadful worldwide types of cancer and affects people leading to *** resonance imaging methods capture skull images that contain healthy and affected *** checked the affected tissue in the slice-by-slice manner,which was timeconsuming and hectic ***,auto segmentation of the affected part is needed to facilitate ***,we have considered a hybrid model that inherits the convolutional neural network(CNN)properties to the support vector machine(SVm)for the auto-segmented brain tumor *** CNN model is initially used to detect brain tumors,while SVm is integrated to segment the tumor region *** proposed method was evaluated on a publicly available BraTS2020 *** statistical parameters used in this work for the mathematical measures are precision,accuracy,specificity,sensitivity,and dice ***,our method achieved an accuracy value of 0.98,which is most prominent than existing ***,the proposed approach is more suitable for medical experts to diagnose the early stages of the brain tumor.

关键词： Brain tumor support vector machine convolutional neural network BraTS classification

基于风机主动控制的风电场低电压穿越能力深度挖掘研究

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中国电机工程学报 2017年第15期37卷 4388-4398页

作者：林湘宁卓毅鑫李正天童宁徐铝洋张伟 m.shoaib Khalid 强电磁与新技术国家重点实验室(华中科技大学) 湖北省武汉市430074

该文基于具备低电压穿越能力的风机在部分电压扰动场景下仍无法成功穿越的场景分析,研究提出风电场内双馈风机可用无功与异步风机无功负荷的协调控制策略。该策略通过列写各风机的电压约束方程并在二维平面上求解可行域,得出最小脱网台... 详细信息

该文基于具备低电压穿越能力的风机在部分电压扰动场景下仍无法成功穿越的场景分析,研究提出风电场内双馈风机可用无功与异步风机无功负荷的协调控制策略。该策略通过列写各风机的电压约束方程并在二维平面上求解可行域,得出最小脱网台数下的无功增发与切机策略,实现多场景电压扰动下风电场低电压穿越能力的进一步挖掘提升,通过对实际风电场的仿真分析,验证了所提策略的有效性。

关键词：风电场低电压穿越能力风机主动控制无功协调减载切机

Discrete element method simulation of disc type furrow openers in paddy soil

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International Journal of Agricultural and Biological Engineering 2020年第4期13卷 103-110页

作者： Fiaz Ahmad Baijing Qiu Qishuo Ding Weimin Ding Zahid mahmood Khan m.ham.ad shoaib Farman Ali Chandio Abdur Rehim Abdul Khaliq School of Agricultural Equipment Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina College of Engineering Nanjing Agricultural UniversityNanjing 210031China Department of Agricultural Engineering Bahauddin Zakariya University 60800MultanPakistan Department of Farm Power and machinery Sindh Agricultural UniversityTandojam 70060Pakistan Department of Soil Science Bahauddin Zakariya University 60800MultanPakistan Department of Irrigation and Drainage University of AgricultureFaisalabad 38000Pakistan

For granular materials,discrete element modeling is one of the best computer tools to simulate their behavior and interactions.A field experiment was carried out to evaluate the performance of disc furrow openers in paddy *** element simulation was done to develop a 3D DEm model for notched,toothed and double disc furrow openers using EDEm *** mindlin contact model with bonding was applied for simulation to fulfill the obligations of the soil moisture and bonding between the cohesive *** and field experimental data were compared to determine the applicability in the different working *** results of the simulation validated the applicability of the Hertz-mindlin contact model with bonding to simulate the no till paddy soil using an extremely narrow tillage *** calibrated value of normal and shear stiffness was 5×10^(7)N/m,and the calibrated value of bond normal and shear strength was 3×10^(7)*** relative error(-1.7%to 20.6%)for the double disc furrow opener was lower as compared with that notch typed(29.2%to 44.4%)and toothed type(31.5%to 45.9%)furrow openers.

关键词： soil tillage discrete element method discrete element modeling furrow opener paddy soil

氮肥和种植密度对晚播棉花根系生长和氮代谢的影响

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氮肥和种植密度对晚播棉花根系生长和氮代谢的影响

作者： shoaib Ahmad 华中农业大学

学位级别：硕士

棉花是世界范围内主要纤维作物。在过去的三十年里,中国是世界上最重要的棉花生产国与消费国,而长江流域棉区是中国棉花主产区之一。成本投入,尤其是化肥投入过高成为棉花种植的主要限制因素。以晚播、增密、减氮和一次施肥为特点的棉... 详细信息

棉花是世界范围内主要纤维作物。在过去的三十年里,中国是世界上最重要的棉花生产国与消费国,而长江流域棉区是中国棉花主产区之一。成本投入,尤其是化肥投入过高成为棉花种植的主要限制因素。以晚播、增密、减氮和一次施肥为特点的棉花新型种植模式,已逐渐取代传统棉花生产模式,且种植效益较高。为进一步明确这种新型种植模式下,密度和施氮量的互补关系,在华中农业大学试验农场进行了2年(2018-2019)大田试验。采用裂区试验设计,以密度为主区(D=6株m,D=8株m,施氮量为副区(N=150 kg ha,N=180 kg ha,N=210 kg ha,同时施用54 kg haPO、1.5 kg haB和180 kg hakO。棉花品种Huamian-3097(Gossypium Hirsutum L.)均于5月24日播种。主要考查了棉花根系、叶片形态,棉花氮代谢、逆境生理及棉花产量等,结果如下:1.D处理的平均籽棉产量高于D,而施氮量的增加也提高了棉花籽棉产量。施氮量的增加提高了两种密度的籽棉产量。D时,DN处理的籽棉产量最高;D时,DN籽棉产量最高,但DN与DN无差异。随着施氮量的增加,根系形态指标量逐渐增加,并于N达最高值。单位面积根干重、鲜重、体积、表面积和长度等,均在DN最大。2.D氮代谢酶活性高于D处理,而增加施氮量也使氮代谢酶活性提高。总的来说,与D相比,N、N显著提高了D的氮代谢酶活性,如GOT(谷草酰乙酸转氨酶)、GPT(谷丙转氨酶)、GOGAT(谷氨酸合酶)、GS(谷氨酰胺合成酶)、Ni R(亚硝酸盐还原酶)和NR(硝酸还原酶)。此外相较于N处理,N和N的游离氨基酸和叶绿素含量更稳定。3.D抗氧化酶活性高于D,同时随施氮量的增加而下降。抗氧化酶(POD、CAT和SOD)活性,高施氮量(N和N)时保持较好水平;因此,N丙二醛(mDA)含量增加,表明N供应不足。结果表明,获得最高籽棉产量的组合是DN或DN,二者具有良好的互补关系。较高密度和较低氮肥或较低密度和较高氮肥提高氮代谢活性,维持较好抗氧化代谢平衡,从而提高作物产量。因此,在长江流域新型棉花种植模式下,密度6株m、氮肥210 kg ha或密度8株m、氮肥180 kg ha是棉花生产最经济的选择。

关键词：棉花根系生长氮代谢氮肥种植密度

Hepatic manifestations of coronavirus disease 2019 infection:Clinical and laboratory perspective

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World Journal of Virology 2022年第6期11卷 453-466页

作者： Farina m Hanif Zain majid shoaib Ahmed Nasir H Luck muhammed mubarak Department of Hepatogastroenterology Sindh Institute of Urology and TransplantationKarachi 74200SindhPakistan Department of Pathology Sindh Institute of Urology and TransplantationKarachi 74200SindhPakistan

The novel coronavirus disease 2019(COVID-19)pandemic,caused by severe acute respiratory syndrome coronavirus 2,has become a global challenge of unprecedented nature since December *** most patients with COVID-19 exhibit mild clinical manifestations and upper respiratory tract involvement,in approximately 5%-10%of patients,the disease is severe and involves multiple organs,leading to multi-organ dysfunction and *** liver and gastrointestinal tract are also frequently involved in *** the context of liver involvement in patients with COVID-19,many key aspects need to be addressed in both native and transplanted *** review focuses on the clinical presentations and laboratory abnormalities of liver function tests in patients with COVID-19 with no prior liver disease,patients with pre-existing liver diseases and liver transplant recipients.A brief overview of the history of COVID-19 and etiopathogenesis of the liver injury will also be described as a prelude to better understanding the above aspects.

关键词： COVID-19 Liver injury SARS-CoV-2 Clinical manifestations Liver function tests Cirrhosis