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A coupled catalyst composed of CoFe_(2)O_(4) magnetic nanoparticle and[HMIM]Br-FeCl_(3) to intensify the oxidative desulfurization of FCC diesel

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Green Chemical Engineering 2021年第4期2卷 441-449页

作者： Yanlin Zhang Xinyu Zhang Guangren Yu Xiaochun Chen ahmed a.abdeltawab Hany El-Hamshary Beijing Key Laboratory of Membrane Science and Technology&College of Chemical Engineering Beijing University of Chemical TechnologyBeijing100029China Department of Chemistry College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

Ionic liquids have been extensively studied as solvents or catalysts for oxidative desulfurization(ODS)of diesel fuel,but it is still a challenge to reduce the desulfurization time and *** this work,a new highly efficient desulfurization system composed of CoFe_(2)O_(4) magnetic nanoparticle,[HMIM]Br-FeCl_(3) and H_(2)O_(2) was developed for the ODS of FCC diesel *** desulfurization performances were investigated including desulfurization time,temperature,volume ratio of IL/oil,O/S molar ratio,dosage of CoFe_(2)O_(4),FeCl_(3) content in ILs,regeneration,and reuse of catalyst and *** to the coupled catalytic roles of CoFe_(2)O_(4) magnetic nanoparticle and[HMIM]Br-FeCl_(3),where Co2t and Fe3t interact with H_(2)O_(2) to produce ·OH radical that converts S-compounds into sulfone and sulfoxide compounds,such a desulfurization system is highly effective in removing S-compound in diesel *** S-content in FCC diesel fuel was reduced from the original 272.8 ppm to 0.5 ppm with 99.82%S-removal efficiency after one step within 8 minunder the optimal conditions of 25℃,8 min,V(IL/oil)=1:10,O/S=20,5 wt%CoFe_(2)O_(4) dosage and n([HMIM]Br)/n(FeCl_(3))=1:1;the desulfurization performance is much better in desulfurization time and steps than other desulfurization systems reported *** desulfurization system can be regenerated and reused without remarkable loss of desulfurization activity.A desulfurization mechanism was proposed.

关键词： CoFe_(2)O_(4)magnetic nanoparticle Ferric chloride ionic liquids Oxidative desulfurization

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Synthesis of polymeric ionic liquids material and application in CO2 adsorption

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Journal of Energy Chemistry 2017年第5期26卷 909-918页

作者： Haiying Ran Jiexin Wang ahmed a.abdeltawab Xiaochun Chen Guangren Yu Yinghao Yu Beijing Key Laboratory of Membrane Science and Technology&College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640GuangdongChina

We synthesized one quaternary ammonium polymeric ionic liquids（PILs）P[VBTHEA]Cl and three imidazolium PILs of P[VEIm]Br, P[VEIm]BF, P[VEIm]PFby free-radical polymerization in solution. These PILs were characterized by FT-IR,H-NMR,C-NMR, TGA, XRD and SEM. Their COadsorption capacities were measured under different pressures and temperatures by constant-volume technique. It was observed that quaternary ammonium PILs of P[VBTHEA]Cl have higher adsorption capacity for COthan those imidazolium PILs, following P[VBTHEA]Cl > P[VEIm]PF> P[VEIm]BF> P[VEIm]Br, which may be ascribed to higher positive charge density on ammonium cation than that on imidazolium cation and thus stronger interaction with CO, consistent with the results from dual-mode adsorption model that ammonium PILs have much higher CObulk absorption than imidazolium PILs. COadsorption capacity of P[VBTHEA]Cl is 9.02 mg/g under 295 K and 1 bar, which is comparable to that of some other PILs, and is much higher than that of the corresponding ILs monomer. These PILs have good adsorption selectivity for COover Nand regeneration efficiency.

关键词： Polymeric ionic liquids CO2 Adsorption

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Nanosecond pulse and dual-wavelength Q-switched 1.5 μm fiber laser using MAX phase Cr2TiAlC2 saturable absorber

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Optoelectronics Letters 2025年第1期21卷 7-12页

作者： ahmed Shakir AL-HITI Hiba HASSAN Department of Electrical Engineering Faculty of Engineering University of Anbar Department of Laser and Optoelectronics Engineering University of Technology-Iraq

We demonstrated a new type of MAX phase material, chromium titanium aluminum carbide（Cr2TiAlC2） polymer film, to generate a passively Q-switched erbium-doped fiber laser（EDFL）. The film thickness was measured to be around 45 μm, which was fabricated using the embedding method with polyvinyl alcohol（PVA） polymer as hoster. The saturable absorber（SA） film demonstrates a dual-wavelength passively Q-switched EDFL which operates at 1 531 nm and 1 560.19 nm, respectively. The Q-switching pulse duration could be varied from 2.46 μs to 770 ns, while the repetition rate varied from 92.76 kHz to 106.6 kHz with an increasing input pumping range from 154 mW to 300 mW. The maximum output power and pulse energy of 15.05 mW and 141.18 nJ were obtained at the maximum input power of 300 mW, respectively.

关键词： Saturable absorbers

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Vascular endothelial growth factor:a double-edged sword in the development of white matter lesions

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Neural Regeneration Research 2025年第1期20卷 191-192页

作者： Narek Manukjan Daniel Fulton Zubair ahmed WMatthijs Blankesteijn Sébastien Foulquier Department of Pharmacology and Toxicology Maastricht UniversityMaastrichtThe Netherlands CARIM-School for Cardiovascular Diseases Maastricht UniversityMaastrichtThe Netherlands Neuroscience and Ophthalmology Institute of Inflammation and AgeingUniversity of BirminghamEdgbastonBirminghamUK Centre for Trauma Sciences Research University of BirminghamEdgbastonBirminghamUK MHeNs-School for Mental Health and Neuroscience Maastricht UniversityMaastrichtThe Netherlands Department of Neurology Maastricht University Medical CenterMaastrichtThe Netherlands

As the population ages,the burden of age-related diseases becomes ***,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common ***,it is becoming clearer that underlying vascular pathology such as cerebral small vessel disease(cSVD)may be a more detrimental cause for dementia(Cuadrado-Godia et al.,2018).It is estimated that 10%-30%of the elderly population and 35%-90%of all dementia patients exhibit signs of *** term cSVD refers to pathology affecting the small vessels of the brain,which can lead to lacunar cerebral infarcts,enlarged perivascular spaces,and cortical hemorrhages(Cuadrado-Godia et al.,2018).CSVD is often associated with cognitive decline,gait problems,and dementia(Cuadrado-Godia et al.,2018).

关键词： pathology becoming white

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N-methyl-2-pyrrolidonium-based Br?nsted-Lewis acidic ionic liquids as catalysts for the hydrolysis of cellulose

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Science China Chemistry 2016年第5期59卷 564-570页

作者： Zheng Zhao Na Li Abdul Waheed Bhutto ahmed A. abdeltawab Salem S. Al-Deyab Guangqing Liu Xiaochun Chen Guangren Yu Beijing Key Laboratory of Membrane Science and Technology College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Department of Chemical Engineering Mehran University of Engineering and TechnologyJamshoro 76062Pakistan Petrochemicals Research Chair College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

We experimentally studied the catalytic performances of a series of Brrnsted-Lewis acidic N-methyl-2-pyrrolidonium metal chlorides （[Hnmp]Cl/MClx, where M=Fe, Zn, A1, or Cu） for the hydrolysis of microcrystalline cellulose （MCC） and cotton to produce reducing sugar. A variety of factors, such as temperature, time, ionic liquid （IL） species, IL dosage, and the concentra- tion of the metal chloride were investigated. [Hnmp]Cl/FeCl3 presented the best hydrolysis performance, affording a 98.8% yield of total reducing sugar from MCC （1 h, 100 ℃, 0.1 g MCC, 0.2 g acidic IL, 2.0 g [Bmim]Cl as solvent）, which is better than or comparable to results previously obtained with other -SO3H functionalized acidic ILs. The hydrolysis performances of [Hnmp]Cl/MClx were rationalized using density functional theory calculations, which indicated that interactions between the metal chlorides and the cellulose, including charge-transfer interactions are important in the hydrolysis of cellulose and degra- dation of glucose. This work shows that Bronsted-Lewis acidic ILs are potential catalysts for the hydrolysis of cellulose to produce sugar.

关键词： cellulose hydrolysis ionic liquid density functional theory

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Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems

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Structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： Sabrina Meddah Sid ahmed Tadjer Abdelhakim Idir Kong Fah Tee Mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

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Influence of biomass density and food to microorganisms ratio on the mixed culture type I methanotrophs enriched from activated sludge

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Journal of Environmental Sciences 2018年第8期30卷 87-96页

作者： ahmed AlSayed ahmed Fergala ahmed Eldyasti Department of Civil Engineering Lassonde School of Engineering York University

Methanotrophic based process can be the remedy to offset the wastewater treatment facilities increasing energy requirements due to methanotroph＇s unique ability to integrate methane assimilation with multiple biotechnological applications like biological nitrogen removal and methanol production. Regardless of the methanotrophic process end product, the challenge to maintain stable microbial growth in the methanotrophs cultivation bioreactor at higher cell densities is one of the major obstacles facing the process upscaling. Therefore, a series of consecutive batch tests were performed to attentively investigate the biomass density influence on type I methanotrophs bacterial growth. In addition, food to microorganisms（F/M）, carbon to nitrogen（C/N） and nitrogen to microorganisms（N/M） ratio effect on the microbial activity was studied for the first time. It was clarified that the F/M ratio is the most influencing factor on the microbial growth at higher biomass densities rather than the biomass density increase, whereas C/N and N/M ratio change, while using nitrate as the nitrogen source,does not influence methanotrophs microbial growth. These study results would facilitate the scaling up of methanotrophic based biotechnology by identifying that F/M ratio as the key parameter that influences methanotrophs cultivation at high biomass densities.

关键词： Methanotrophs Wastewater treatment Food to microorganisms ratio Biomass density

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Colorectal cancer in Arab world:A systematic review

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World Journal of Gastrointestinal Oncology 2021年第11期13卷 1791-1798页

作者： Nahed A Makhlouf Muhammad Abdel-Gawad Aya M Mahros Sameh A Lashen Mariam Zaghloul ahmed Eliwa Eman E Elshemy Zainab Ali-Eldin Doaa.abdeltawab Fathiya El-Raey Dalia Omran Marwa Khalaf Nancy Fanous ahmed Shawkat Abdelmohsen ahmed Abu-Elfatth Mohamed Abdelghani Mahmoud Farouk Mohamed Abdelaziz Mohamed Alboraie Department of Tropical Medicine and Gastroenterology Faculty of MedicineAssiut UniversityAssiut 71515Egypt Department of Hepatology Gastroenterologyand Infectious DiseasesAl-Azhar UniversityAssiut 71631Egypt Department of Hepatology Gastroenterology and Infectious DiseasesKafrelsheikh UniversityKafrelsheikh 33656Egypt Department of Internal Medicine Alexandria UniversityAlexandria 21521Egypt Department of Internal Medicine Al-Azhar UniversityCairo 11884Egypt Department of Hepatogastroenterology and Infectious Diseases Al-Azhar UniversityCairo 11651Egypt Department of Internal Medicine Ain Shams UniversityCairo 11646Egypt Department of Hepatogastroenterology and Infectious diseases Faculty of MedicineAl-Azhar UniversityDamietta 34511CairoEgypt Department of Endemic Medicine Cairo UniversityCairo 12613Egypt Department of Tropical Medicine and Gastroenterology Assiut Liver CenterAssiut 71511Egypt Department of Gastroenterology Hepatology and EndoscopyPolice Authority HospitalCairo 12654Egypt Department of Clinical Oncology and Nuclear Medicine Al-Azhar UniversityCairo 11824Egypt

BACKGROUND The incidence of colorectal cancer(CRC)is increasing among young individuals in the Arab world as well as in other regions of the *** To explore the incidence and prevalence of CRC in the Arab *** The PubMed,Scopus,Web of Science,EBSCO and Wiley databases were searched to retrieve relevant articles irrespective of the language or the publication *** search terms were("colon OR rectum OR sigmoid OR rectal OR colonic OR colorectal")AND("cancer OR malignancy OR malignant OR neoplasm")AND("Jordan"OR"United Arab Emirates"OR"Bahrain"OR"Tunisia"OR"Algeria"OR"Djibouti"OR"Saudi Arabia"OR"Sudan"OR"Syria"OR"Somalia"OR"Iraq"OR"Oman"OR"Palestine"OR"Qatar"OR"Comoros"OR"Kuwait"OR"Lebanon"OR"Libya"OR"Egypt"OR"Morocco"OR"Mauritania"OR"Yemen").Reviews,metaanalyses,and articles containing nonoriginal data were *** articles were screened,and relevant data were *** statistics were used for data *** Nine studies were *** of the studies provided information regarding the prevalence of *** prevalence of CRC was 0.72% in Saudi Arabia and 0.78% in the United Arab Emirate,while in Egypt,it ranged from 0.4% to 14%.Four studies showed information regarding the *** annual incidence rate of CRC in Qatar was 7.5/100000/*** Egypt,the crude incidence rate(CIR)in males was 3.1 for colon cancer and 1 for rectal cancer,while in females,it was 2.3 for colon cancer and 0.8 for rectal *** age-standardized rate for CRC incidence in 2003 was 36.90 for males,26.50 for females,and 30.49 for both sexes in Saudi *** 2016,the CIRs in Saudi Arabia were 3.6 and 2.1 in females for colon cancer and rectal cancer,respectively,while in males,it was 3.3 and 2.8 for colon cancer and rectal cancer,*** study in Egypt revealed that 25% of CRC cases occurred among individuals younger than 40 years *** There is a considerable prevalence of CRC in some Arab *** studies are n

关键词： Colorectal cancer Incidence Prevalence Arab world

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On Learning Adaptive Service Compositions

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Journal of Systems Science and Systems Engineering 2021年第4期30卷 465-481页

作者： ahmed Moustafa Department of Computer Science Nagoya Institute of TechnologyGokiso-choShowa-kuNagoyaAichi466-8555Japan Faculty of Informatics Zagazig UniversityZagazigEgypt

Service composition is an important and effective technique that enables atomic services to be combined together to forma more powerful service,i.e.,a composite *** the pervasiveness of the Internet and the proliferation of interconnected computing devices,it is essential that service composition embraces an adaptive service provisioning *** learning has emerged as a powerful tool to compose and adapt Web services in open and dynamic ***,the most common applications of reinforcement learning algorithms are relatively inefficient in their use of the interaction experience data,whichmay affect the stability of the learning process when deployed to cloud *** particular,they make just one learning update for each interaction *** paper introduces a novel approach that aims to achieve greater data efficiency by saving the experience data and using it in aggregate to make updates to the learned *** proposed approach devises an offline learning scheme for cloud service composition where the online learning task is transformed into a series of supervised learning tasks.A set of algorithms is proposed under this scheme in order to facilitate and empower efficient service composition in the cloud under various policies and different *** results of our experiments show the effectiveness of the proposed approach for composing and adapting cloud services,especially under dynamic environment settings,compared to their online learning counterparts.

关键词： Service composition reinforcement learning cloud services offline learning

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CTAB-assisted fabrication of hierarchical flower-like magnesium oxide adsorbent for enhanced removal performance towards phosphate

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Journal of Magnesium and Alloys 2023年第9期11卷 3231-3240页

作者： Saeed ahmed State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Department of Chemistry The University of LahoreLahore 54590Pakistan Department of Chemistry University of ChakwalPakistan

In this work, a series of hierarchical flower-like magnesium oxide(MgO) adsorbents were successfully fabricated in a cetyltrimethylammonium bromide(CTAB) assisted solvothermal route using hexamethylenetetramine(HMTA) as a precipitating agent. Effects of CTAB feeding amount on the structure, morphology, pore structure, and corresponding adsorption behavior were investigated. The hierarchical gardenias flower-like MgO demonstrated a surface area of 336.54 m^(2)·g^(-1) at a minimum ratio of the CTAB/Mg^(2+)was 0.02 in the reaction system. The hierarchical MgO phosphate removal capacity was 348.32 mg·g^(-1), which followed the pseudo-second-order and Freundlich isotherm model obtained from the large surface area and appropriate pore size. The value of n also suggests the feasible nature of phosphate adsorption under the examined conditions. Indeed, this CTAB assisted solvothermal method can provide a new understanding to tune the desired properties of a material by merely adjusting the reaction parameters of MgO.

关键词： Adsorption CTAB-assisted Magnesium oxide Phosphate removal Solvothermal

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