检索结果-南通市图书馆

Methane Steam Reforming on Supported Nickel Based Catalysts. Effect of Oxide ZrO2, La2O3and Nickel Composition

在线全文

学校读者我要写书评

暂无评论

Open Journal of Physical chemistry 2013年第2期3卷 89-96页

作者： Akila Belhadi Mohamed Trari chérifa rabia Ouiza cherifi Laboratory of chemistry of Natural Gas Faculty of Chemistry (USTHB) Algiers Algeria

The catalytic properties of Ni (4 and 10 wt%) supported on both La2O3 and ZrO2 were investigated for the methane steam reforming reaction between 475℃ and 700℃ at atmospheric pressure. The catalysts were prepared by the impregnation method and characterized by several techniques (atomic absorption, BET method, X-ray diffraction and TG-TPO). The catalytic activity of Ni/support systems strongly depends on both of the nature and physico-chemical properties of the support. No deactivation was observed in catalytic systems, whatever the reaction temperature indicating high stability of the catalyst.

关键词： Methane Steam Reforming Nickel Coke Supported Catalysts

Catalytic Reduction of Benzaldehyde Under Hydrogen Flow over Nickel-Containing Mesoporous Silica Catalysts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Physical chemistry 2012年第1期2卷 73-80页

作者： Adel Saadi Kahina Lanasri Khaldoun Bachari Djamila Halliche chérifa rabia Laboratoire de chimie du Gaz Naturel Faculty of Chemistry University of Sciences and Technology Houari Boumediene Algiers Algeria

The hydrogenation of benzaldehyde over a series of nickel-containing mesoporous silicas with different nickel contents was studied at atmospheric pressure in the range temperature of 393 - 513 K under H2 ?ow. These materials (noted Nin-HMS with n = Si/Ni = 50, 25, 15) have been prepared at room temperature using a route based on hydrogen bonding and self-assembly between neutral primary amine micelles (S0) and neutral inorganic precursors (I0). They were characterized by their chemical analysis, BET surface area, XRD, FT-IR, and SEM microscopy. The obtained products were benzylalcohol, toluene, benzene with yields depending on the nickel content (Si/Ni ratio) and reaction temperature. The products of benzaldehyde hydrogenation (benzylalcohol, and toluene) and hydrogenolysis (benzene) were preferentially formed at low/middle and high reaction temperature respectively. The mesoporous Ni-containing materials were very active hydrogenation catalysts with almost 90% selectivity to benzylalcohol product and showed excellent stability. A mechanism in which the reaction could be initiated by a benzaldehyde reduction over Nin-HMS materials under hydrogen flow with formation of reaction products is proposed.

关键词： Nickel HMS Benzaldehyde Reduction Mesoporous Materials

Dehydrocyclization of n-Hexane over Heteropolyoxometalates Catalysts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in chemical Engineering and Science 2013年第1期3卷 82-92页

作者： Abdellah Eid Ouarda Benlounes Hikmat S. Hilal chérifa rabia Smain Hocine Laboratoire de chimie Appliquée et de Genie chimique Universite Mouloud Mammeri Tizi-Ouzou Algeria Laboratoire de chimie du Gaz Naturel Institut de Chimie USTHB Alger Algeria Laboratory of Semiconductor and Solar Energy Research Chemistry Department An-Najah N. University Nablus Palestine

The catalytic dehydrocyclization of n-hexane was studied here for the first time using a number of compounds based on H3PMo12O40. The described catalysts were prepared by either replacing the acidic proton with counter-ions such as ammonium or transition metal cations (NH4+, Fe3+, K+), or by replacing Mo6+ with (Ni3+, Co3+, Mn3+) in the polyoxometalate framework, as reported earlier. For comparison purposes, the known (TBA)7PW11O39 catalyst system was used. All reactions were conducted at different temperatures in the range 200 - 450. The Keggin structure of these heteropolycompounds was ascertained by XRD, UV and IR measurements. 31P NMR measurements and thermal behaviour of the prepared catalysts were also studied. These modified polyoxometalates exhibited heterogeneous superacidic catalytic activities in dehydrocyclization of n-hexane into benzene, cyclohexane, cyclohexene and cyclohexadiene. The catalysts obtained by substituting the acidic proton or coordination atom exhibited higher selectivity and stability than the parent compound H3PMo12O40. Catalytic activity and selectivity were heavily dependent on the composition of the catalyst and on the reaction conditions. At higher temperatures, the catalyst exhibited higher conversion efficiency at the expense of selectivity. Using higher temperatures (>400) in the presence of hydrogen carrier gas, selectivity towards dehydrocyclization ceased and methane dominated. To explain the results, a plausible mechanism is presented, based on super-acidic nature of the catalyst systems.

关键词： Dehydrocyclization Heteropolyacid Catalyst n-Hexane Keggin Ion

Adaptation of Federated Explainable Artificial Intelligence for Efficient and Secure E-Healthcare Systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第3期78卷 3413-3429页

作者： rabia Abid Muhammad Rizwan Abdulatif Alabdulatif Abdullah Alnajim Meznah Alamro Mourade Azrour Department of Computer Science Kinnaird College for WomenLahorePakistan College of Science and Engineering University of DerbyDerbyDE221GBUK Department of Computer Science College of ComputerQassim UniversityBuraydah51452Saudi Arabia Department of Information Technology College of ComputerQassim UniversityBuraydah51452Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh84428Saudi Arabia STI Laboratory IDMS TeamFaculty of Sciences and TechniquesMoulay Ismail University of MeknèsMeknesMorocco

Explainable Artificial Intelligence(XAI)has an advanced feature to enhance the decision-making feature and improve the rule-based technique by using more advanced Machine Learning(ML)and Deep Learning(DL)based *** this paper,we chose e-healthcare systems for efficient decision-making and data classification,especially in data security,data handling,diagnostics,laboratories,and *** Machine Learning(FML)is a new and advanced technology that helps to maintain privacy for Personal Health Records(PHR)and handle a large amount of medical data *** this context,XAI,along with FML,increases efficiency and improves the security of e-healthcare *** experiments show efficient system performance by implementing a federated averaging algorithm on an open-source Federated Learning(FL)*** experimental evaluation demonstrates the accuracy rate by taking epochs size 5,batch size 16,and the number of clients 5,which shows a higher accuracy rate(19,104).We conclude the paper by discussing the existing gaps and future work in an e-healthcare system.

关键词： Artificial intelligence data privacy federated machine learning healthcare system security

Capparis spinosa L waste activated carbon as an efficient adsorbent for crystal violet toxic dye removal: Modeling, optimization by experimental design, and ecological analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

chinese Journal of chemical Engineering 2024年第7期71卷 283-302页

作者： Mohammed Benjelloun Youssef Miyah Salma Ssouni Soulaiman Iaich Mohamed El-habacha Salek Lagdali Khadija Saka El Mustafa Iboustaten Abdelaziz Ait Addi Sanae Lairini rabia Bouslamti Laboratory of Materials ProcessesCatalysisand EnvironmentHigher School of TechnologySidi Mohamed Ben Abdellah UniversityFez 30070Morocco Ministry of Health and Social Protection Higher Institute of Nursing Professions and Health TechniquesFez/Meknes 30070Morocco Laboratory of Biochemistry Faculty of MedicinePharmacy and DentistrySidi Mohamed Ben Abdellah UniversityFez 30070Morocco Laboratory of Applied chemistry and Environment Faculty of SciencesIbnou Zohr UniversityAgadir 80322Morocco Research Team of Energy and Sustainable Development Higher School of TechnologyIbnou Zohr UniversityGuelmim 81000Morocco Organic chemistry and Physical chemistry Laboratory Faculty of SciencesIbnou Zohr UniversityAgadir 80322Morocco

Textile dyes are dramatic sources of pollution and non-aesthetic disturbance of aquatic life and therefore represent a potential risk of bioaccumulation that can affect living *** is imperative to reduce or eliminate these dyes from liquid effluents with innovative biomaterials and ***,this research aims to highlight the performance of Capparis spinosa L waste-activated carbon(CSLW-AC)adsorbent to remove crystal violet(CV)from an aqueous *** mechanism of CV adsorption on CSLW-AC was evaluated based on the coupling of experimental data and different characterization *** efficiency of the CSLW-AC material reflected by the equilibrium adsorption capacity of CV could reach more than 195.671 mg·g^(–1) when 0.5 g·L^(–1) of CSLW-AC(Particle size≤250μm)is introduced into the CV of initial concentration of 100 mg·L^(–1) at pH 6 and temperature 65℃ and in the presence of potassium ions after 60 min of contact time according to the one parameter at a time *** adsorption behavior of CV on CSLW-AC was found to be consistent with the pseudo-second-order kinetic model and Frumkin's linear isothermal *** thermodynamic aspects indicate that the process is physical,spontaneous,and *** optimization of the process by the Box Behnken design of experiments resulted in an adsorption capacity approaching 183.544 mg·g^(–1)([CV]=100 mg·L^(–1) and[CSLW-AC]=0.5 g·L^(–1) at 35 min).The results of the Lactuca sativa seeds germination in treated CV(70%),adsorbent solvent and thermal regeneration(more than 5 cycles),and process cost analysis(1.0484 USD·L^(–1))tests are encouraging and promising for future exploitations of the CSLW-AC material in different industrial fields.

关键词： Box Behnken Capparis spinosa L waste-activated carbon Cost analysis Isotherm Kinetic Regeneration

Adult neurogenesis:a real hope or a delusion?

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第1期19卷 6-15页

作者： Ghulam Hussain rabia Akram Haseeb Anwar Faiqa Sajid Tehreem Iman Hyung Soo Han chand Raza Jose-Luis Gonzalez De Aguilar Neurochemicalbiology and Genetics Laboratory(NGL) Department of PhysiologyFaculty of Life SciencesGovernment College UniversityFaisalabadPunjabPakistan Department of Physiology School of MedicineClinical Omics InstituteKyungpook National UniversityDaeguKorea Department of Zoology Faculty of Chemistry and Life SciencesGovernment College UniversityLahorePakistan INSERM U1118Mécanismes Centraux et Péripheriques de la NeurodégénérescenceStrasbourgFranceUniversitéde StrasbourgStrasbourgFrance

Adult neurogenesis,the process of creating new neurons,involves the coordinated division,migration,and differentiation of neural stem *** process is restricted to neurogenic niches located in two distinct areas of the brain:the subgranular zone of the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle,where new neurons are generated and then migrate to the olfactory *** has been thought to occur only during the embryonic and early postnatal stages and to decline with age due to a continuous depletion of neural stem ***,recent years have seen tremendous progress in our understanding of adult brain neurogenesis,bridging the knowledge gap between embryonic and adult ***,we discuss the current status of adult brain neurogenesis in light of what we know about neural stem *** this notion,we talk about the importance of intra cellular signaling molecules in mobilizing endogenous neural stem cell prolife *** on the current understanding,we can declare that these molecules play a role in targeting neurogenesis in the mature ***,to achieve this goal,we need to avoid the undesired proliferation of neural stem cells by controlling the necessary checkpoints,which can lead to tumorigenesis and prove to be a curse instead of a blessing or hope.

关键词： adult neurogenesis aging brain-derived neurotrophic factor dentate gyrus hippocampus neural stem cells neurotrophic factors Notch oxidative stress stem cells subgranular zone

Automated screening of primary cell-based aptamers for targeting and therapy of pancreatic cancer

在线全文

学校读者我要写书评

暂无评论

chinese chemical Letters 2024年第2期35卷 300-304页

作者： Zhukang Guo Baijiang Jin Yile Fang Lian Jin Song Li Yan Deng Zhu chen Hui chen Yuanying Zhang rabia Usman Nongyue He State Key Laboratory of Digital Medical Engineering School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Hunan Key Laboratory of Biomedical Nanomaterials and Devices Hunan University of TechnologyZhuzhou 412007China Department of Molecular Biology Jiangsu Cancer HospitalNanjing 210009China

Although it has been developed for many years, nucleic acid aptamer screening technology still fails to be widely used, a considerable part of it is due to the variability of tumor cell morphology, which leads to the use of immortalized cell lines in the laboratory to screen nucleic acid aptamers for recognition ability of tumor cells in the diseased *** address this, primary cells that can be stably passaged were isolated and extracted from spontaneous tumors of genetically engineered pancreatic ductal adenocarcinoma model mice in this ***, an automated screening instrument for nucleic acid aptamers developed autonomously by our group was used to perform efficient aptamer screening using a limited number of cells, and the obtained nucleic acid aptamers were affinity verified at the cellular ***, to answer the question of the cell growth environment difference on the recognition ability of nucleic acid aptamers, we verified its targeting ability to tumors in vivo on a nude mice xenograft tumor model, and further used a common antitumor drug doxorubicin combined with nucleic acid aptamers to verify the drug loading ability of this aptamer combined with the targeting therapeutic ability.

关键词： Aptamer Cell-SELEX Automatic instrument Combination therapy Pancreatic cancer

Dynamics of holographic images of scalar-tensor-vector gravity-AdS black holes

在线全文

学校读者我要写书评

暂无评论

chinese Physics C 2024年第09期 278-294页

作者：胡馨匀 M.Israr Aslam rabia Saleem 曾晓雄 College of Economic and Management Chongqing Jiaotong University Department of Mathematics COMSATS University Islamabad Lahore-Campus State Key Laboratory of Mountain Bridge and Tunnel Engineering Chongqing Jiaotong University Department of Mechanics Chongqing Jiaotong University

Using AdS/CFT correspondence,we analyze the holographic Einstein images via the response function of the complex scalar field as a probe wave on an AdS Schwarzschild scalar-tensor-vector gravity（STVG） black hole（BH）.We find that the amplitude of the response function || decreases with increasing values of coupling parameter a and increases with decreasing temperature *** frequency ω of the wave source also plays a significant role in wave periods;as we increase the values of ω,the periods of waves decrease,indicating that the total response function closely depends on the wave ***,we investigate the optical appearance of the holographic images of the BH in *** found that the holographic ring always appears with surrounding concentric stripes when the observer is located at the north pole,and an extremely bright ring appears when the observer is at the position of the photon sphere of the *** ring changes into a luminosity-deformed ring or a bright light spot as the observational angle *** corresponding brightness profiles show that the luminosity of the ring decreases and the shadow radius increases with increasing values of *** relation between temperature T and the inverse of the horizonheis discussed;T is small at the beginning of the horizon he and then increases as the horizon radius *** effect can be used to distinguish the STVG BH solution from other BH ***,these significant features are also reflected in the Einstein ring and corresponding brightness *** addition,we compare the results obtained by wave optics and geometric optics,which align well,implying that the holographic scheme adopted in this study is valid.

关键词：

Catalytic Reduction of Benzaldehyde under Hydrogen Flow over Nickel-Containing Mesoporous Silica Catalysts

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论