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磁性Zn-BTC@SiO_2@Fe_3O_4催化剂及其对甲苯与对甲基苯甲酰氯酰基化反应的催化性能

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石油学报（石油加工） 2014年第1期30卷 126-133页

作者：李庆远 muhammad ammar 季生福王景艳刘想北京化工大学化工资源有效利用国家重点实验室北京100029

以磁性SiO2@Fe3O4颗粒为核,在其表面原位合成了金属-有机骨架材料Zn-BTC,制备了一系列新型的Zn-BTC@SiO2@Fe3O4磁性催化剂。采用SEM、TEM、XRD、IR、NH3-TPD和VSM等技术对磁性催化剂的结构和性质进行了表征,并且评价了Zn-BTC@SiO2@Fe3O... 详细信息

以磁性SiO2@Fe3O4颗粒为核,在其表面原位合成了金属-有机骨架材料Zn-BTC,制备了一系列新型的Zn-BTC@SiO2@Fe3O4磁性催化剂。采用SEM、TEM、XRD、IR、NH3-TPD和VSM等技术对磁性催化剂的结构和性质进行了表征,并且评价了Zn-BTC@SiO2@Fe3O4磁性催化剂对甲苯和对甲基苯甲酰氯酰基化反应的催化性能。结果表明,一定Zn-BTC含量范围的磁性Zn-BTC@SiO2@Fe3O4催化剂具有好的超顺磁性和酸性;在甲苯和对甲基苯甲酰氯酰基化反应中表现出良好的催化活性,且随着催化剂中Zn-BTC含量的增加,该反应的甲苯转化率逐渐提高;其中Zn-BTC质量分数为36.7%的Zn-BTC@SiO2@Fe3O4催化剂的催化性能最佳,在120℃下,该反应的甲苯转化率可达52.6%;反应后的催化剂经外磁场回收重复使用5次,甲苯的转化率没有明显下降。新型Zn-BTC@SiO2@Fe3O4磁性催化剂在多相催化酰基化反应中具有很好的应用前景。

关键词：金属-有机骨架 Zn-BTC 磁性催化剂酰基化

BLOWING UP AND MULTIPLICITY OF SOLUTIONS FOR A FOURTH-ORDER EQUATION WITH CRITICAL NONLINEARITY

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Acta Mathematica Scientia 2015年第6期35卷 1511-1546页

作者： Siwar ammar Mokhles HAMMAMI Department of mathematics University of Monastir Department of mathematics Faculty of Sciences of sfax University of Sfax

In this paper, we consider the following nonlinear elliptic problem ： △2u =｜u｜n-4^-u＋u｜u｜q-1u,in Ω,△u=u=0 on ЭΩ,where Ω is a bounded and smooth domain in R^n,n∈{5,6,7},u is a parameter and q∈]4/（n-4）,（12-n）/（n-4）].We study the solutions which concentrate around two points of Ω. We prove that the concentration speeOs are the same order and the distances of the concentration points from each other and from the boundary are bounded. For Ω=（Ωa）a a smooth ringshaped open set, we establish the existence of positive solutions which concentrate at two points of Ω. Finally, we show that for u〉0, large enough, the problem has at least many positive solutions as the Ljusternik-Schnirelman category of Ω.

关键词： fourth order elliptic equations critical Sobolev exponent blow up solution

GaitDONet: Gait Recognition Using Deep Features Optimization and Neural Network

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Computers, Materials & Continua 2023年第6期75卷 5087-5103页

作者： muhammad Attique Khan Awais Khan Majed Alhaisoni Abdullah Alqahtani ammar Armghan Sara A.Althubiti Fayadh Alenezi Senghour Mey Yunyoung Nam Department of Computer Science HITEC UniversityTaxilaPakistan Computer Sciences Department College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia College of Computer Engineering and Sciences Prince Sattam bin Abdulaziz UniversityAl-KharjSaudi Arabia Department of Electrical Engineering College of EngineeringJouf UniversitySakaka 72388Saudi Arabia Department of Computer Science College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia Department of ICT Convergence Soonchunhyang UniversityKorea

Human gait recognition(HGR)is the process of identifying a sub-ject(human)based on their walking *** subject is a unique walking pattern and cannot be simulated by other ***,gait recognition is not easy and makes the system difficult if any object is carried by a subject,such as a bag or *** article proposes an automated architecture based on deep features optimization for *** our knowledge,it is the first architecture in which features are fused using multiset canonical correlation analysis(MCCA).In the proposed method,original video frames are processed for all 11 selected angles of the CASIA B dataset and utilized to train two fine-tuned deep learning models such as Squeezenet and *** transfer learning was used to train both fine-tuned models on selected angles,yielding two new targeted models that were later used for feature *** are extracted from the deep layer of both fine-tuned models and fused into one vector using *** improved manta ray foraging optimization algorithm is also proposed to select the best features from the fused feature matrix and classified using a narrow neural network *** experimental process was conducted on all 11 angles of the large multi-view gait dataset(CASIA B)dataset and obtained improved accuracy than the state-of-the-art ***,a detailed confidence interval based analysis also shows the effectiveness of the proposed architecture for HGR.

关键词： Human gait recognition biometric deep learning features fusion optimization neural network

EXISTENCE OF POSITIVE SOLUTIONS FOR A CLASS OF PARABOLIC EQUATIONS WITH NATURAL GROWTH TERMS AND L^1 DATA

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Acta Mathematica Scientia 2014年第4期34卷 1127-1144页

作者： Kaouther ammar Hicham REDWANE Department of Mathematics Faculty of sciencesTaibah UniversityP.O. Box 344 Al MadinahSaudi Arabia Facult'e des Sciences Juridiques Economiques et SocialesUniversit'e Hassan 1B.P. 784SettatMorocco

We study a class of nonlinear parabolic equations of the type：δb（u）/δt-div（a（x,t,u）△u）＋y（u）｜△u｜^2=f,where the right hand side belongs to L^1（Q）, b is a strictly increasing C^1-function and -div（a（x, t, u）△u） is a Leray-Lions operator. The function g is just assumed to be continuous on R and to satisfy a sign condition. Without any additional growth assumption on u, we prove the existence of a renormalized solution.

关键词： renormalized solutions natural growth terms L^1 data

Fake News Detection Using Machine Learning and Deep Learning Methods

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Computers, Materials & Continua 2023年第11期77卷 2079-2096页

作者： ammar Saeed Eesa Al Solami Department of Computer Science Comsats University IslamabadWah Cantt47010Pakistan Department of Cybersecurity College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia

The evolution of the internet and its accessibility in the twenty-first century has resulted in a tremendous increase in the use of social media *** social media sources contribute to the propagation of fake news that has no real validity,but they accumulate over time and begin to appear in the feed of every consumer producing even more *** sustain the value of social media,such stories must be distinguished from the true *** a result,an automated system is required to save time and *** classification of fake news and misinformation from social media data corpora is the subject of this *** preprocessing and data improvement procedures are used to gather and preprocess two fake news *** text features are extracted using word embedding models Word2vec and Global Vectors for Word representation while textual features are extracted using n-gram approaches named Term Frequency-Inverse Document Frequency and Bag of Words from both datasets *** Encoder Representations from Transformers(BERT)is also employed to derive embedded representations from the input ***,three Machine Learning(ML)and two Deep Learning(DL)algorithms are utilized for fake news *** also carries out the classification of embedded outcomes generated by it in parallel with the ML and DL *** terms of overall performance,the DL-based Convolutional Neural Network stands out in the case of the first while BERT performs better in the case of the second dataset.

关键词： Machine learning deep learning fake news feature extraction

A comprehensive simulator for assessing the reliability of a photovoltaic panel peak power tracking system

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Frontiers in Energy 2015年第2期9卷 170-179页

作者： Nabil KAHOUL Mourad HOUABES ammar NECAIBIA Laboratoire d' Electrotechnique d' Annaba Badji Mokhtar-AnnabaUniversity Annaba 23000 Algeria Research Unit of Renewable Energy in Saharan Middle (URER/MS) Adrar 01000 Algeria

When designing a maximum power point tracking （MPPT） algorithm, it is often difficult to correctly predict, before field testing, the behavior of this MPPT under varying solar irradiation on photovoltaic （PV） panels. A solution to this problem is to design a maximum power point trackers simulator of a PV system used to test MPPT algorithms. This simulator must have the same role as the MPPT card of the PV panel and thus will fully emulate the response of a real MPPT card of the PV panel. Therefore, it is a good substitute to help to test the peak power trackers of the PV system in the laboratory. This paper describes a simple peak power trackers simulator of the PV system which has a short response time thus, can be used to test MPPT algorithms under very rapid variation condition. The obtained results and the theoretical operation confirm the reliability and the superior perfor- mance of the proposed model.

关键词： photovoltaicdesign maximum powermicroprocessormodule DC-DC converter,point tracking (MPPT) card,

Interactive effects of deficit irrigation and vermicompost on yield,quality,and irrigation water use efficiency of greenhouse cucumber

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Journal of Arid Land 2022年第11期14卷 1274-1292页

作者： Halimeh PIRI Amir NASERIN ammar A ALBALASMEH Department of Water Engineering Faculty of College of Water and SoilUniversity of ZabolZabol ***Iran Department of Water Engineering Agricultural Sciences and Natural Resources University of KhuzestanMollasani ***Iran Department of Natural Resources and the Environment Faculty of AgricultureJordan University of Science and TechnologyIrbid 22110Jordan

Water scarcity is the most significant barrier to agricultural development in arid and semi-arid *** irrigation is an effective solution for managing agricultural water in these *** use of additives such as vermicompost(VC)to improve soil characteristics and increase yield is a popular *** this,there is still a lack of understanding of the interaction between irrigation water and VC on various *** study aimed to investigate the interaction effect of irrigation water and VC on greenhouse cucumber yield,yield components,quality,and irrigation water use efficiency(IWUE).The trials were done in a split-plot design in three replicates in a semi-arid region of southeastern Iran in 2018 and *** levels of VC in the experiments,i.e.,10(V_(1)),15(V_(2)),and 20 t/hm^(2)(V_(3)),and three levels of irrigation water,i.e.,50%(I_(1)),75%(I_(2)),and 100%(I_(3))of crop water requirement were *** results showed that the amount of irrigation water,VC,and their interaction significantly affected cucumber yield,yield components,quality,and IWUE in both *** the amount of irrigation water and VC application rates reduced the weight,diameter,length,and cucumber *** maximum yield(175 t/hm^(2))was recorded in full irrigation using 20 t/hm^(2)of VC,while the minimum yield(98 t/hm^(2))was found in I_(1)V_(1)*** maximum and minimum values of IWUE were recorded for I_(1)V_(3)and I_(3)V_(1)treatments as 36.07 and 19.93 kg/(m^(3)•hm^(2)),***,reducing irrigation amount decreased chlorophyll a and b,but increased vitamin ***,the maximum carbohydrate and protein contents were obtained in mild water-stressed conditions(I_(2)).Although adding VC positively influenced the value of quality traits,no significant difference was observed between V_(2)and V_(3)*** on the results,adding VC under full irrigation conditions leads to enhanced yield and ***,in the case of applying deficit ir

关键词： irrigation water use efficiency greenhouse size and weight of fruit soil amendment semi-arid region

User activities and the heteroseneity of urban space:The case of Dahiyat Al Hussein park

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Frontiers of Architectural Research 2020年第4期9卷 837-857页

作者： Ahlam ammar Sharif Department of Architecture Philadelphia UniversityAmman 19392Jordan

Urban researchers have maintained a constant interest in the complexity and continuity of urban space *** have applied actor-network theory(ANT)to investigate the heterogeneity of spaces and present them through the networks of their users'***,these accounts are predominantly limited in examining the extent to which these spaces may be heterogeneous when exploring such *** paper draws on recent ANT scholarship,which employs an ethnographic research conducted in a main park in a housing project at Dahiyat Al Hussein in Amman,*** findings describe the complex and unpredictable negotiations that occur with in spaces by documenting the varieties and in terrelations among user activity networks within this common and shared urban *** research reveals the extent to which spaces,parks in this case,may be heterogeneous by unpacking their *** conclusions and in sights assert then ecessity of paying attention to design detail and creating designs that are responsive to evolving user activities.

关键词： Actor-network theory User activity networks Space heterogeneity Spatial translations Relational patterns

Users as co-designers:Visual-spatial experiences at Whitworth Art Gallery

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Frontiers of Architectural Research 2020年第1期9卷 106-118页

作者： Ahlam ammar Sharif Department of Architecture Philadelphia UniversityAmmanJordan

The importance of building users in the architectural field has been increasingly acknowledged in architectural *** studies have applied actor-network theory(ANT)to highlight the ways through which users are embedded in relation to the built ***,many of these studies are limited in recognizing the diverse ways users manipulate these relations as they experience the same built environment *** study draws on a recent ANT scholarship by summarizing the ethnographic research of Whitworth Art Gallery in Manchester,United *** show that users see and react to the same built environment in different ways that are not limited to their alignment or misalignment with the *** extend to include diverse interpretations and reactions(destructing,ignoring,noticing,attending,and interacting).The different user experiences explored in this research demonstrate three main themes,namely,entanglements,continuity,and transformation,which suggest new ways of recognizing the need for increasingly adaptable and inviting designs that address different user preferences and desires.

关键词： Actor-network theory Architectural design Design process Design technology User behavior