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Gamma irradiation-induced effects on the properties of TiO_2 on fluorine-doped tin oxide prepared by atomic layer deposition

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Nuclear Science and Techniques 2018年第7期29卷 191-197页

作者： Syed Mansoor Ali M.S.Algarawi Turki S.ALKhuraiji S.S.Alghamdi Muhammad hammad Aziz M.Isa Department of Physics and Astronomy College of ScienceKing Saud University National Center for Irradiation Technology King Abdulaziz City for Science and Technology Department of Physics COMSATS Institute of Information and Technology Department of Physics Faculty of ScienceUniversity of GujratHafiz Hayat Campus

The effect of gamma irradiation with different doses(25–75 kGy) on TiO_2 thin films deposited by atomic layer deposition has been studied and characterized by X-ray diffraction(XRD),photoluminescence measurements,ultraviolet–visible(UV–Vis) spectroscopy,and impedance *** XRD results for the TiO_2 films indicate an enhancement of crystallization after irradiation,which can be clearly observed from the increase in the peak intensities upon increasing the gamma irradiation *** UV–Vis spectra demonstrate a decrease in transmittance,and the band gap of the TiO_2 thin films decreases with an increase in the gamma irradiation *** Nyquist plots reveal that the overall charge-transfer resistance increases upon increasing the gamma irradiation *** equivalent circuit,series resistance,contact resistance,and interface capacitance are measured by simulation using Z-view *** present work demonstrates that gamma irradiation-induced defects play a major role in the modification of thestructural,electrical,and optical properties of the TiO_2 thin films.

关键词： TiO2 原子层 Gamma 性质氧化物 gamma Nyquist 光致发光

印刷电路板和微管换热器的热工水力特性数值研究

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印刷电路板和微管换热器的热工水力特性数值研究

作者： hammad Aslam Bhatti 华北电力大学(北京)

学位级别：硕士

同传统的管壳式换热器相比,以超临界二氧化碳为工质的紧凑型换热器能够有效提高热力循环效率,降低各部件尺寸,对小型堆的设计有着重要意义。紧凑式换热器主要分为两种类型,分别是印刷式换热器和微通道换热器。为了分析紧凑型换热器的热... 详细信息

同传统的管壳式换热器相比,以超临界二氧化碳为工质的紧凑型换热器能够有效提高热力循环效率,降低各部件尺寸,对小型堆的设计有着重要意义。紧凑式换热器主要分为两种类型,分别是印刷式换热器和微通道换热器。为了分析紧凑型换热器的热工水力性能,本文基于超临界二氧化碳工质的热工水力特性,分析了印刷式换热器和微通道换热器的主要优势,设计了三种印刷式换热器模型和三种微通道换热器模型,引入几何无量纲数和雷诺数作为变量,采用计算流体动力学方法(CFD)进行了数值模拟。印刷式换热器通道模型分别为具有15°角的锯齿形通道、波状通道和翼型鳍通道。结果表明,锯齿形通道具有比波状通道和AFF通道更好的传热性能。在压力损失的情况下,翼型鳍片通道表现出更好的性能,其次是波纹通道和锯齿形通道,应进一步研究具有不同翅片类型的直槽。对于微通道换热器,研究了三种不同的微通道直径模型,其微通道外径均为2mm,内径分别为0.8mm、1mm、1.2mm。结果表明,增加微通道直径可以提高换热效率,随着微通道直径的增加,摩擦系数增加,同时压力损失也会增加。同时考虑换热效率和压力损失的影响,引入面积优化因子作为衡量指标,结果表明外径为2mm,内径为0.8mm的微通道换热器综合性能最好。本文对超临界二氧化碳在紧凑式换热器中的热工水力特性进行了深入研究,对今后的进一步的弯曲通道模拟计算,高雷诺数情况下的研究以及实验设计提供了参考依据和研究基础。

关键词： CFD PCHE 微管 S-CO2 热工水力

Daylight Quality in Healthcare Design, Daylight Measurements Results and Discussion, Case Study： Jordan University Hospital

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Journal of Energy and Power Engineering 2017年第3期11卷 141-149页

作者： Sahar Diab Bayan Abu Qadourah Riziq hammad Department of Architecture Jordan University Amman 11942 Jordan

This study＇s purpose is to evaluate and analyse the indoor daylight quality in Pediatrics Ward in JUH （Jordan University Hospital）. It conducts an investigative analysis associated with an evaluative approach for the daylight situation in patient rooms in the children section. A multi-method approach used including on-site measurements, and building model to develop a framework for lighting design in Paediatrics Ward, in order to determine whether the current quality meets the recommended values for patient rooms by CIBSE or not. The study considered the following variables： the differences in daylight environments （illuminance, luminance level, daylight factor）, and the physical environment properties of patient rooms in the hospital. The study found that the indoor daylight performance in terms of illuminance, luminance level, and daylight factor in east patient rooms are higher than the recommended values by CIBSE in the area nearest to glass window at the morning and less than the recommended values in the depth of the room at afternoon. Therefore, solar reflective technologies and shading system must be provided for enhanced day lighting control, avoid excessive glare and to guarantee a good level of visual comfort for patients and staff while reducing artificial lighting demand.

关键词： JUH indoor daylight health care CIBSE control system of day lighting energy consumption.

基于激光干涉仪的对角线和步进对角线测量方法的实验误差分析

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基于激光干涉仪的对角线和步进对角线测量方法的实验误差分析

作者： Hafiz hammad Younis 广东海洋大学

学位级别：硕士

分别使用对角线和步进对角线两种测量方法,通过测量机床工作台不同直线的定位误差来确定三轴数控加工中心的空间误差。到目前为止,空间误差测量方法的相关研究已经日渐成熟,但缺少针对对角线和步进对角线测量方法所得平均空间误差的研... 详细信息

分别使用对角线和步进对角线两种测量方法,通过测量机床工作台不同直线的定位误差来确定三轴数控加工中心的空间误差。到目前为止,空间误差测量方法的相关研究已经日渐成熟,但缺少针对对角线和步进对角线测量方法所得平均空间误差的研究分析。本文基于对角线和步进对角线测量方法提出一种实验误差分析方法;采用步进对角线测量方法,通过英国Renishaw公司的XL-80型激光干涉仪,分别测量六种不同路径的定位误差,再利用实验误差分析方法得出不同路径相应的空间误差。对角线和步进对角线测量方法的起点和终点相同,并且分别给出了详细的测量方法。为了对比测量结果,本文建立了一个数学模型;通过实验测量得出对角线测量方法的平均空间误差小于步进对角线测量方法,直线测量误差随机床工作台测量点位置和高度的变化而变化;结果表明,对角线测量方法优于步进对角线测量方法。实验结果的目的是为了更好的了解和广泛应用两种空间误差测量方法对应的平均空间误差分析方法。

关键词：直线轴直线测量空间误差测量方法对角线和步进对角线

Predictions of future hydrological conditions and contribution of snow and ice melt in total discharge of Shigar River Basin in Central Karakoram,Pakistan

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Research in Cold and Arid Regions 2017年第6期9卷 599-612页

作者： Javed Hassan Rijan Bhakta Kayastha Ahuti Shrestha Iram Bano Sayed hammad Ali Haleem Zaman Magsi Himalayan Cryosphere Climate and Disaster Research CenterDepartment of Environmental Science and EngineeringSchool of ScienceKathmandu UniversityNepal Department of Earth Sciences Karakoram International University Gilgit-Baltistan 15100Pakistan

The high mountains of Hindu-Kush Karakoram and Himalaya(HKKH) contain a large volume of snow and ice, which are the primary sources of water for the entire mountainous population of HKKH. Thus, knowledge of these available resources is very important in relation to their sustainable use. A Modified Positive Degree Day Model was used to simulate daily discharge with the contribution of snow and ice melt from the Shigar River Basin, Central Karakoram, Pakistan. The basin covers an area of 6,921 km2 with an elevation range of 2,204 to 8,611 m a.s.l.. Forty percent of the total area is glaciated among which 20% is covered by debris and remaining 80% by clean ice and permanent snow. To simulate daily discharge, the entire basin was divided into 26 altitude belts. Remotely sensed land cover types are derived by classifying Landsat images of 2009. Daily temperature and precipitation from Skardu meteorological station is used to calibrate the glacio-hydrological model as an input variable after correlating data with the Shigar station data(r=0.88). Local temperature lapse rate of 0.0075 °C/m is used. 2 °C critical temperature is used to separate rain and snow from precipitation. The model is calibrated for 1988~1991 and validated for 1992~1997. The model shows a good Nash-Sutcliffe efficiency and volume difference in calibration(0.86% and 0.90%) and validation(0.78% and 6.85%). Contribution of snow and ice melt in discharge is 32.37% in calibration period and 33.01% is validation period. The model is also used to predict future hydrological regime up to 2099 by using CORDEX South Asia RCM considering RCP4.5 and RCP8.5 climate *** future snow and ice melt contributions in both RCP4.5 and RCP8.5 are 36% and 37%, respectively. Temperature seems to be more sensitive as compared to other input variables, which is why the contribution of snow and ice in discharge varies significantly throughout the whole century.

关键词： positive degree day factor simulated discharge daily meteorological variables debris covered ice clean ice

Rationally optimized generation of integrated Escherichia coli with stable and high yield lycopene biosynthesis from heterologous mevalonate(MVA)and lycopene expression pathways

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Synthetic and Systems Biotechnology 2021年第2期6卷 85-94页

作者： Muhammad hammad Hussain Qi Hong Waqas Qamar Zaman Ali Mohsin Yanlong Wei Ning Zhang Hongqing Fang Zejian Wang Haifeng Hang Yingping Zhuang Meijin Guo State Key Laboratory of Bioreactor Engineering East China University of Science and Technology 130 Meilong RoadShanghai200237PR China Institute of Environmental Sciences and Engineering School of Civil and Environmental Engineering National University of Sciences and Technology(NUST)Sector H-12Islamabad44000Pakistan Beijing Institute of Biotechnology 20 Dongda StreetBeijing100071PR China

The stability and high productivity of heterogeneous terpenoid production in Escherichia coli expression system is one of the most key issues for its large scale *** the current study on taking lycopene biosynthesis as an example,an integrated Escherichia coli system has been generated successfully,which resulted into stable and high lycopene *** this process,two modules of mevalonate(MVA)pathway and one module of lycopene expression pathway were completely integrated in the ***,the copy number and integrated position of three modules of heterologous pathways were rationally ***,a strain DH416 equipped with heterogeneous expression pathways through chromosomal integration was efficiently derived from parental strain *** evolving DH416 strain efficiently produced the lycopene level of 1.22 g/L(49.9 mg/g DCW)in a 5 L fermenter with mean productivity of 61.0 mg/L/***,the integrated strain showed more genetic stability than the plasmid systems after successive 21st passage.

关键词： Escherichia coli Lycopene biosynthesis Rational model of expression pathways Integrated MVA pathway Fermentation

Endoscopic assessment and management of early esophageal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2014年第8期6卷 275-288页

作者： Ghassan M Hammoud Hazem hammad Jamal A Ibdah Division of Gastroenterology and Hepatology University of Mis-souri Columbia MO 65212 United States

Esophageal carcinoma affects more than 450000people worldwide and the incidence is rapidly *** the United States and Europe,esophageal adenocarcinoma has superseded esophageal squamous cell carcinoma in its *** cancer has a high mortality rates secondary to the late presentation of most patients at advanced *** screening is recommended for patients with multiple risk factors for cancer in Barrett’s *** risk factors include chronic gastroesophageal reflux disease,hiatal hernia,advanced age,male sex,white race,cigarette smoking,and *** annual risk of esophageal cancer is approximately 0.25%for patients without dysplasia and 6%for patients with high-grade *** percent of all esophageal adenocarcinoma in the United States is early stage with disease confined to the mucosa or *** significant morbidity and mortality of esophagectomy make endoscopic treatment an attractive *** American Gastroenterological Association recommends endoscopic eradication therapy for patients with high-grade *** modalities for treatment of early esophageal adenocarcinoma include endoscopic resection techniques and endoscopic ablative techniques such as radiofrequency ablation,photodynamic therapy and *** therapy should be precluded to patients with no evidence of lymphovascular *** tumor recurrence is low after endoscopic therapy and is predicted by poor differentiation of tumor,positive lymph node and submucosal *** resection should be offered to patients with deep submucosal invasion.

关键词： Esophageal adenocarcinoma High grade dysplasia,endoscopic ultrasound Gastroesophageal reflux Barrett’s esophagus Chromoendoscopy Narrow band imaging Endoscopic mucosal resection Radiofrequency ablation

Assessment of Incidentally Detected Simple Renal Cyst in Pediatric Patient Based on the Modified Bosniak Classification —Incidentally Detected Simple Renal Cyst in Pediatric

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Open Journal of Pediatrics 2020年第2期10卷 356-362页

作者： Amna Kashgari Eman Ajlan Abdullah Al hammad Syed Jamil King Saud Bin Abdulaziz University for Health Sciences Riyadh Saudi Arabia Medical Imaging Department King Abdullah Specialized Children Hospital/King Saud Bin Abdulaziz University for Health Sci-ence Riyadh Saudi Arabia Pediatric Department King Abdullah Specialized Children Hospital/King Saud Bin Abdulaziz University for Health Science Ri-yadh Saudi Arabia

Renal cysts in pediatric patients are uncommon lesion. A modified Bosniak classification system for renal cysts based on US has been developed to evaluate pediatric renal cysts to identify the simple cyst or cystic tumour. Nevertheless, it is not widely used. In this retrospective study, all incidentally detected renal cysts by ultrasound performed in children and the reproducibility of modified Bosniak classification to guide the radiological and clinical follow up.

关键词： Renal Cyst Ultrasound Pediatric Modified Bosniak Classification

A Novel Island Detection Methodology for the Realization of Smart Grid

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Smart Grid and Renewable Energy 2011年第4期2卷 330-337页

作者： hammad Khan Anastasia Tjandra Herbert Iu Victor Sreeram 不详

Responding to the problem of increased load demand, progress has been made to develop a new smarter infrastructure, which employs a decentralised approach. This smart decentralised system, termed smart grid, is composed of micro grids which utilise a combination of distributed energy resources (DER). The DERs can either be operated in parallel with the grid or in autonomous condition (intentional-islanding). Operating the DER under intentional islanding condition is seen as the next stage in smart grid’s future development which requires intelligent control implementation. In order to utilise this intelligent control, immediate detection of islanding is essential. This paper proposes a new smarter islanding detection method, which implements the forecast capability of smart grid by detecting the fluctuations before islanding occurs. The proposed method has been tested in simulation and compared against the current islanding detection methods. The simulation results have successfully proven the benefits of the new proposed method over the current methodologies in island detection.

关键词： Distributed Generation (DG) Islanding Non-Detection Zone (NDZ) Circuit Breaker Contact Parting Time