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Fabrication of Polyoxometalate Nanofiber Materials and Their Catalytic Activity in Oxidation Transformation

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Fabrication of Polyoxometalate Nanofiber Materials and Their...

作者： Ayman Abdallah ahmed ismail 东北师范大学

学位级别：硕士

多金属氧酸盐(polyoxometalates,POMs)的Br(?)nsted酸性和自身的氧化还原性,尤其本身强的多电子转移能力可以应用于光电材料和催化氧化领域中。在POMs催化研究领域POMs易溶于水和有机溶剂,导致催化反应难以回收,并且POMs的比表面积小,... 详细信息

多金属氧酸盐(polyoxometalates,POMs)的Br(?)nsted酸性和自身的氧化还原性,尤其本身强的多电子转移能力可以应用于光电材料和催化氧化领域中。在POMs催化研究领域POMs易溶于水和有机溶剂,导致催化反应难以回收,并且POMs的比表面积小,极大的限制了其在催化领域的应用。因此,如何提高POMs的循环使用性并制备长效稳定的POMs材料一直是POMs催化领域的研究热点。而开发新的固体POMs合成策略,实现POMs高效、稳定的固载是人们追求的目标。静电纺丝技术是构建一维纳米材料常用的方式,也是将POMs固载化的有效手段。本论文以静电纺丝技术为基础,围绕POMs一维纳米复合材料的合成、表征及催化氧化性能展开研究。具体内容如下:利用静电纺丝技术合成了[AlO/Polymethylmethacrylate]/[HPMo10VO/Polymethylmethacrylate]([AlO/PMMA]/[HPMoV/PMMA])“Janus”双功能纳米纤维催化剂。“Janus”纳米纤维催化剂的形貌通过IR、31P NMR、SEM等手段证明。在氧化淀粉和HMF过程中发现,催化剂的催化效果与HPMoVO固载量有关,当固载量为20%时,得到最佳的催化氧化效果。在氧气氧化淀粉反应中,最佳反应条件为:1.0 g淀粉,5 mg催化剂,70 C,10h,得到的氧化淀粉羧基含量为0.55 mol/100 g。HMF氧气氧化的最佳条件:63 mg HMF,40 mg催化剂,100℃,6 h,得到82.6%HMF的转化率和54.8%DFF的产率。并且催化剂具有良好的稳定性。

关键词：多金属氧酸盐淀粉氧化 HMF氧化静电纺丝技术纳米纤维

Handling Big Data in Relational Database Management Systems

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Computers, Materials & Continua 2022年第9期72卷 5149-5164页

作者： Kamal ElDahshan Eman Selim ahmed ismail Ebada Mohamed Abouhawwash Yunyoung Nam Gamal Behery Faculty of Science Al-Azhar UniversityCairoEgypt Faculty of Computer and Artificial Intelligence Damietta UniversityEgypt Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast LansingMI48824USA Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea

Currently, relational database management systems (RDBMSs)face different challenges in application development due to the massive growthof unstructured and semi-structured data. This introduced new DBMS categories, known as not only structured query language (NoSQL) DBMSs, whichdo not adhere to the relational model. The migration from relational databasesto NoSQL databases is challenging due to the data complexity. This study aimsto enhance the storage performance of RDBMSs in handling a variety of *** paper presents two approaches. The first approach proposes a convenientrepresentation of unstructured data storage. Several extensive experimentswere implemented to assess the efficiency of this approach that could resultin substantial improvements in the RDBMSs storage. The second approachproposes using the JavaScript Object Notation (JSON) format to representmultivalued attributes and many to many (M:N) relationships in relationaldatabases to create a flexible schema and store semi-structured data. Theresults indicate that the proposed approaches outperform similar approachesand improve data storage performance, which helps preserve software stabilityin huge organizations by improving existing software packages whose replacement may be highly costly.

关键词： Big data RDBMS NoSQL DBMSs MongoDB MySQL unstructured data semi-structured data

Functional activity of the rectum:A conduit organ or a storage organ or both?

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World Journal of Gastroenterology 2006年第28期12卷 4549-4552页

作者： ahmed Shafik Randa M Mostafa ismail Shafik Olfat EI-Sibai Ali A Shafik Department of Surgery and Experimental Research Faculty of MedicineCairo UniversityCairoEgypt Department of Physiology Faculty of MedicineSharkia UniversityBanha-ZagazigEgypt Department of Surgery Faculty of MedicineMenoufia UniversityShebin El-KomEgypt

AIM： To investigate whether the degree of rectal distension could define the rectum functions as a conduit METHODS： Response of the rectal and anal pressure to 2 types of rectal balloon distension, rapid voluminous and slow gradual distention, was recorded in 21 healthy volunteers （12 men, 9 women, age 41.7 ± 10.6 years）. The test was repeated with sphincteric squeeze on urgent sensation. RESULTS： Rapid voluminous rectal distension resulted in a significant rectal pressure increase （P 〈 0.001）, an anal pressure decline （P 〈 0.05） and balloon expulsion. The subjects felt urgent sensation but did not feel the 1^st rectal sensation. On urgent sensation, anal squeeze caused a significant rectal pressure decrease （P 〈 0.001） and urgency disappearance. Slow incremental rectal filling drew a rectometrogram with a ＂tone＂ limb representing a gradual rectal pressure increase during rectal filling, and an ＂evacuation limb＂ representing a sharp pressure increase during balloon expulsion. The curve recorded both the ist rectal sensation and the urgent sensation. CONCLUSION： The rectum has apparently two functions： transportation （conduit） and storage, both depending on the degree of rectal filling. If the fecal material received by the rectum is small, it is stored in the rectum until a big volume is reached that can affect a degree of rectal distension sufficient to initiate the defecation reflex. Large volume rectal distension evokes directly the rectoanal inhibitory reflex with a resulting defecation.

关键词： Anal pressure Rectal pressure Rectometry First rectal sensation

Syntheses of Some 3-[1′(1′H)-Substituent-pyrazol-5′-yl] benzo[5,6]coumarins

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Chinese Journal of Chemistry 2002年第7期20卷 670-675页

作者： E-LDEEN Ibrahim Mohey AL-WAKEEL El-Sayed ismail El-MAWLA ahmed Gad Faculty of Education Suez Canal University Port-said Egypt Faculty of Science Suez Canal University Ismailia Egypt

3-[1′ (1′ H)-Substituent-pyrazol-5′-yl] benzo[5, 6] coumarins and3-(1′,2′-oxazol-5′-yl)benzo[5,6]coumarin were prepared via condensation of3-(2′-formyl-1′-chlorovinyl) benzo [5, 6] coumarin with hydrazine derivatives or *** of 3-[1′(1′ H)-pyrazol-5′-yl] benzo[5, 6] coumarin with alkyl halidcs, olefiniccompounds or acid chlorides are described.

关键词： heterocycle synthesis pyrazol-5′-ylbenzo [5, 6] coumarin alkylation atpyrazole nitrogen

A New Generative Mathematical Model for Coverless Steganography System Based on Image Generation

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Computers, Materials & Continua 2023年第3期74卷 5087-5103页

作者： Al-Hussien Seddik Mohammed Salah Gamal Behery ahmed El-harby ahmed ismail Ebada Sokea Teng Yunyoung Nam Mohamed Abouhawwash Department of Computer Science Faculty of ScienceMinia UniversityMiniaEgypt Department of Computer Science Faculty of Computers and Artificial IntelligenceDamietta UniversityNew DamiettaEgypt Department of ICT Convergence Soonchunhyang UniversityAsan31538Korea Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast Lansing48824MIUSA

The ability of any steganography system to correctly retrieve the secret message is the primary criterion for measuring its ***,researchers have tried to generate a new natural image driven from only the secret message bits rather than using a cover to embed the secret message within it;this is called the stego *** paper proposes a new secured coverless steganography system using a generative mathematical model based on semi Quick Response(QR)code and maze game image *** system consists of two *** first component contains two processes,encryption process,and hiding *** encryption process encrypts secret message bits in the form of a semi-QR code image whereas the hiding process conceals the pregenerated semi-QR code in the generated maze game *** the other hand,the second component contains two processes,extraction and decryption,which are responsible for extracting the semi-QR code from the maze game image and then retrieving the original secret message from the extracted semi-QR code image,*** results were obtained using the bit error rate(BER)*** results confirmed that the system achieved high hiding capacity,good performance,and a high level of robustness against attackers compared with other coverless steganography methods.

关键词： Coverless steganography data hiding information security QR code maze game

Telehealth utilization among Egyptian population and health institutional readiness:An exploratory study

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中西医结合护理杂志(英文) 2023年第3期5卷 188-196页

作者： Basma Mohamed OSMAN Maaly Zayed MOHAMED Shaimaa Ali Mohamed ismail lamiaa Saad Abd ALLAH Marwa Mamdouh SHABAN Department of Community Health Nursing Faculty of NursingCairo UniversityCairoEgypt Department of Nursing Administration Faculty of NursingCairo UniversityCairoEgypt

Objective:This study aimed to assess the public’s perspectives and the health institutions’readiness for telehealth utilization in ***:A cross-sectional study design was employed,and data were collected from a convenient sample of 800 Egyptian citizens and 26 nursing administrators and information technology personnel from 16 governmental hospitals and 10 private hospitals between January and March *** Egyptian community utilization of telehealth questionnaire and the telemedicine hospital readiness assessment were used to collect the ***:The results revealed that 35.1%of the general Egyptian population used telehealth services and 43%expressed willingness to use them in *** perceived by the general Egyptian population,the most prevalent barriers to telehealth utilization were communication barriers(97.6%),lack of confidence in health professionals(77.6%),technological limitations(72.5%),the need for physical examination(25%),and privacy concerns(10%).Regarding hospital readiness,42%of governmental hospitals were not taking any initiative to implement telehealth services,and 15.4%were at the beginner level,meaning that some steps had been ***,the hospital was still far from being able to implement telehealth *** contrast,private hospitals were either at the beginner or advanced ***:Although the use of telehealth services in Egypt has increased,there is a need to address the barriers to public utilization and improve hospitals’readiness to implement telehealth services to enhance public usage.

关键词： Attitude barriers hospital readiness public use telehealth nursing practice nursing administration

Amination of biochar surface from watermelon peel for toxic chromium removal enhancement

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Chinese Journal of Chemical Engineering 2021年第8期34卷 199-222页

作者： Mohamed A.El-Nemr Ibrahim M.A.ismail Nabil M.Abdelmonem ahmed El Nemr Safaa Ragab Department of Chemical Engineering Faculty of EngineeringCairo UniversityGizaEgypt Renewable Energy Program Zewail City of Science and TechnologyEgypt Environmental Division National Institute of Oceanography and FisheriesKayet BeyEl-AnfoushyAlexandriaEgypt

Watermelon peel residues were used to produce a new biochar by dehydration *** new biochar has undergone two methods of chemical modification and the effect of this chemical modification on its ability to adsorb Cr(VI)ions from aqueous solution has been *** biochars,Melon-B,Melon-BO-NH_(2) and Melon-BO-TETA,were made from watermelon peel via dehydration with 50%sulfuric acid to give Melon-B followed by oxidation with ozone and amination using ammonium hydroxide to give Melon-BO-NH_(2) or Triethylenetetramine(TETA)to give *** prepared biochars were characterized by BET,BJH,SEM,FT-IR,TGA,DSC and EDAX *** highest removal percentage of Cr(VI)ions was 69%for Melon-B,98%for Melon-BO-NH_(2) and 99%for Melon-BO-TETA biochars of 100 mg·L^(−1) Cr(VI)ions initial concentration and 1.0 g·L^(−1) adsorbents *** unmodified biochar(Melon-B)and modified biochars(Melon-BO-NH_(2) and Melon-BO-TETA)had maximum adsorption capacities(Q_(m))of 72.46,123.46,and 333.33 mg·g^(−1),*** amination of biochar reduced the pore size of modified biochar,whereas the surface area was *** obtained data of isotherm models were tested using different error function *** Freundlich,Tempkin and Langmuir isotherm models were best fitted to the experimental data of Melon-B,Melon-BO-NH_(2) and Melon-BO-TETA,*** adsorption rate was primarily controlled by pseudo-second–order rate ***,the functional groups interactions are important for adsorption mechanisms and expected to control the adsorption *** adsorption for the Melon-B,Melon-BO-NH_(2) and Melon-BO-TETA could be explained for acid–base interaction and hydrogen bonding interaction.

关键词： Waste treatment Powder technology Citrullus lanatus Hexavalent chromium Biochar amination Adsorption

Joint Optimal Power Source Sizing and Data Collection Trip Planning for Advanced Metering Infrastructure Enabled by Unmanned Aerial Vehicles

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Journal of Modern Power Systems and Clean Energy 2022年第5期10卷 1337-1348页

作者： Haiam Shahin Mostafa F.Shaaban Mahmoud H.ismail Hebat-Allah M.Mourad ahmed Khattab Department of Electronics and Communications Engineering Facultyof EngineeringCairo UniversityGiza 12613Egypt IEEE Department of Electrical Engineering American University of SharjahPOBox 26666SharjahThe United Arab Emirates

The use of unmanned aerial vehicles(UAVs) in the collection of data from wireless devices, sensor nodes, and the Internet of Things(IoT) devices has recently received significant attention. In this paper, we investigate the data collection process from a set of smart meters in advanced metering infrastructure(AMI) enabled by UAVs. The objective is to minimize the total annual cost of the electric utility by jointly optimizing the number of UAVs, their power source sizing, the charging locations as well as the data collection trip planning. This is achieved while considering the energy budgets of batteries of UAVs and the required amount of collected data. The problem is formulated as a mixed-integer nonlinear programming(MINLP), which is decoupled into two sub-problems where a candidate UAV and a number of buildings are first grouped into trips via genetic algorithms(GAs), and then the optimum trip path is found using a traveling salesman problem(TSP) branch and bound algorithm. Simulation results show that the battery capacity or the number of UAVs increases as the coverage area or the density increases.

关键词： Advanced metering infrastructure unmanned aerial vehicle power source sizing trip planning genetic algorithm

Study on Rotation-Invariant in Aerial Object Detection using Rotatable Bounding Boxes

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Study on Rotation-Invariant in Aerial Object Detection using...

作者： AL-SOSWA,MOHAMMED ismail ahmed 南京理工大学

学位级别：硕士

目前,神经网络和深度学习的理论与方法广泛应用于计算机视觉和目标检测的研究,其研究成果已广泛用于自动驾驶、航空出行、安防等领域。传统的目标检测方法依靠绘制在目标上的矩形,通过水平和垂直边界框来确定目标位置。航空图像中的物... 详细信息

目前,神经网络和深度学习的理论与方法广泛应用于计算机视觉和目标检测的研究,其研究成果已广泛用于自动驾驶、航空出行、安防等领域。传统的目标检测方法依靠绘制在目标上的矩形,通过水平和垂直边界框来确定目标位置。航空图像中的物体方向随机,密集且周围复杂,因此对传统的物体检测模型构成了挑战。传统的矩形框会忽略物体的方向,从而导致物体定位减少,并且在目标密集情况下重叠的框会限制进一步的处理,例如目标的理解和检测。为了克服这些局限性,本文对目标检测方法进行改进,实现更高效,更精确的检测。首先,修改目标检测边界框的定义,包括旋转,高度,宽度和框的中心点,有效的定位目标并减少背景像素的干扰;其次,应用金字塔特征网络学习多层特征生以检测小面积目标;然后,对边界框的常规编码方案进行了修改以适合提出的可旋转边界框,以便更好地估计目标的方向和位置;最后,为了克服负样本和正样本之间的不平衡问题,将难负样挖掘（Hard Negative Mining,HNM）和焦点损失（focal loss,FL）结合起来使用,从而解决正负样本不平衡的问题。通过分析模型在四个数据集上的目标检测结果,并与（Single Shot Detector,SSD）和Faster R-CNN进行比较,表明本文提出的模型超越了传统的边界框模型,尤其是旋转和密集目标。

关键词：旋转不变性卷积神经网络特征金字塔网络焦点损失可旋转边框目标检测