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Effect of diluent and reaction parameter on selective oxidation of propane over MoVTeNb catalyst using nanoflow catalytic reactor

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Journal of Natural Gas Chemistry 2008年第2期17卷 130-134页

作者： Restu Kartiko Widi Sharifah Bee Abdul Hamid robert schlgl Department of Mathematic and Natural Science University of SurabayaTG 6th floor Raya Kalirungkut 60293SurabayaIndonesia Combinatorial Technology and Catalysis Research Centre University of Malaya50603Kuala LumpurMalaysia combinatorial Technology and Catalysis Research Centre University of Malaya50603Kuala LumpurMalaysia: Fritz-Haber-Institute der Max-Planck-Gesellschaft Faradayweg 4-614195 BerlinGermany

The selective oxidation of propane to acrylic acid over an MoVTeNb mixed oxide catalyst, dried and calcined before reaction has been studied using high-throughput instrumentation, which is called nanoflow catalytic reactor. The effects of catalyst dilution on the catalytic performance of the MoVTeNb mixed oxide catalyst in selective oxidation of propane to acrylic acid were also investigated. The effects of some reaction parameters, such as gas hourly space velocity （GHSV） and reaction temperature, for selective oxidation of propane to acrylic acid over diluted MoVTeNb catalyst have also been studied. The configuration of the nanoflow is shown to be suitable for screen catalytic performance, and its operating conditions were mimicked closely to conventional laboratory as well as to industrial conditions. The results obtained provided very good reproducibility and it showed that preparation methods as well as reaction parameters can play significant roles in catalytic performance of these catalysts.

关键词： selective oxidation propane acrylic acid MoVTeNb mixed oxide catalyst

ChemSuChem-a memorial to Dangsheng Su

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Journal of Energy Chemistry 2021年第10期30卷 250-252,I0008页

作者： robert schlögl Bingsen Zhang Qiang Zhang Xinhe Bao Department of Inorganic Chemistry Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4-614195 BerlinGermany Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of Catalysis CAS Center for Excellence in NanoscienceDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Whoever met Dangsheng Su(D.S.)will remember this encounter with a personality that brought together the *** Chinese Austrian got to know and estimate the fine details of the small German-speaking culture within the We... 详细信息

关键词： remember details Eastern

Probing the intrinsic catalytic activity of carbon nanotubes for the metal-free oxidation of aromatic thiophene compounds in ionic liquids

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Journal of Energy Chemistry 2019年第5期28卷 131-137页

作者： Qingqing Gu Yuxiao Ding Zigeng Liu Yangming Lin robert schlogl Saskia Heumann Dangsheng Su Shenyang National Laboratory for Material Science Institute of Metal ResearchChinese Academy of SciencesWenhua Road 72Shenyang 110016LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-3645470 Millheim a.d.RuhrGermany Fritz Haber Institute of the Max Planck Society Faradayweg 4-614195 BerlinGermany

A metal-free catalytic system combining oxidized carbon nanotubes (oCNTs) and ionic liquids (ILs) is presented for the oxidation of aromatic thiophene compounds with H2O2 as an oxidant. The oCNTs exhibit impressively high activity and stability in the system, which show an even better performance than those of some reported metal catalysts. The ILs are proved to have indispensable influence on the enhanced catalytic performance of the oCNTs. Detailed characterization by TG-MS and XPS demonstrates that the carbonyl groups are the active sites for the oxidation process, which is further supported by the deactivation and the model catalysts experiments. The quantitative analysis of different oxygen groups in oCNTs could be achieved by an isothermal temperature programmed TG-MS method. The concentration of carbonyl groups is 1.46 mmol per 1 g oCNTs and the tuiriover frequency of oCNTs could also be obtained (10.7 h^-1 in the presence of OmimPF6). H2O2 decomposition experiments combined with the EPR results reveal that the presence of OmimPF6 can avoid the intermediate HO· to form O2 and then improve the catalytic performance of oCNTs for the oxidation of dibenzothiophene.

关键词： Carbon nanotubes Metal-free catalysis Oxidative desulfurization Ionic liquids

Visualizing the importance of oxide-metal phase transitions in the production of synthesis gas over Ni catalysts

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Journal of Energy Chemistry 2020年第11期29卷 178-186页

作者： Luis Sandoval-Diaz Milivoj Plodinec Danail Ivanov Stephane Poitel Adnan Hammud Hannah C.Nerl robert schldgl Thomas Lunkenbein Department of Inorganic Chemistry Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4-614195 BerlinGermany Electron Spectrometry and Microscopy Laboratory School of Basic SciencesEcole Polytechnique Federale de Lausanne1015 LausanneSwitzerland Max Planck Institute for Chemical Energy Conversion StiftstraJSe 34-3645470 Miihlheim a.d.RuhrGermany

Synthesis gas, composed of H2 and CO, is an important fuel which serves as feedstock for industrially relevant processes, such as methanol or ammonia synthesis. The efficiency of these reactions depends on the H2: CO ratio, which can be controlled by a careful choice of reactants and catalyst surface ***, using a combination of environmental scanning electron microscopy(ESEM) and online mass spectrometry, direct visualization of the surface chemistry of a Ni catalyst during the production of synthesis gas was achieved for the first time. The insertion of a homebuilt quartz tube reactor in the modified ESEM chamber was key to success of the setup. The nature of chemical dynamics was revealed in the form of reversible oxide-metal phase transitions and surface transformations which occurred on the performing catalyst. The oxide-metal phase transitions were found to control the production of synthesis gas in the temperature regime between 700 and 900 ℃ in an atmosphere relevant for dry reforming of methane(DRM, CO2: CH4=0.75). This was confirmed using high resolution transmission electron microscopy imaging, electron energy loss spectroscopy, thermal analysis, and C18O2 labelled *** dedicated operando approach of simultaneously studying the surface processes of a catalyst and its activity allowed to uncover how phase transitions can steer catalytic reactions.

关键词： Dry reforming of methane Partial oxidation of methane Environmental scanning electron microscopy Synthesis gas Operando

Dynamic carbon surface chemistry: Revealing the role of carbon in electrolytic water oxidation

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Journal of Energy Chemistry 2020年第8期29卷 155-159,I0006页

作者： Yuxiao Ding Qingqing Gu Alexander Klyushin Xing Huang Sakeb H.Choudhury Ioannis Spanos Feihong Song Rik Mom Pascal Dungen Anna K.Mechler robert schlogl Saskia Heumann Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-36Mtilheim an der Ruhr 45470Germany Fritz-Haber-Institut der Max-Planck Gesellschaft Faradayweg 4-6Berlin 14195Germany Research Group Catalysis for Energy Helmholtz-Zentrum Berlin fur Materialien und Energie GmbHAlbert-Einstein-Strasse 1512489 BerlinGermany

Carbon materials have been widely used as electrodes, but the mechanistic roles are still not clear due to the complexity of the carbon surface chemistry. Herein we clarify that intrinsic material properties of carbon have to be activated by extrinsic factors. Pure carbon has no catalytic activity when used as electrode for electrocatalytic water oxidation. The evolution of oxygen functional groups on the carbon surface with increasing potential and the subsequent formation of real active sites with iron impurities from the electrolyte have been confirmed. These in-situ formed active sites protect the carbon from deep oxidation. This unprecedented finding not only provides insight into the dynamic evolution of carbon electrode surface chemistry and raises awareness of the need for detailed surface analysis under operando conditions, but also suggests a direction for the development of scalable and high-performance carbonbased electrode systems for various electrochemical applications.

关键词： Carbon chemistry Carbon catalysis Carbon electrode Water splitting Iron impurity

Multi-Scale Dilated Convolution Network for SPECT-MPI Cardiovascular Disease Classification with Adaptive Denoising and Attenuation Correction

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 299-327页

作者： A.robert Singh Suganya Athisayamani Gyanendra Prasad Joshi Bhanu Shrestha Department of Computational Intelligence SRM Institute of Science and TechnologyKattankulathur603203Tamil NaduIndia School of Computing Sastra Deemed to be UniversityThanjavur613401Tamil NaduIndia Department of Artificial Intelligence&Software Kangwon National UniversitySamcheok25913Republic of Korea Department of Information Convergence System Graduate School of Smart ConvergenceKwangwoon UniversitySeoul01897Republic of Korea

Myocardial perfusion imaging(MPI),which uses single-photon emission computed tomography(SPECT),is a well-known estimating tool for medical diagnosis,employing the classification of images to show situations in coronary artery disease(CAD).The automatic classification of SPECT images for different techniques has achieved near-optimal accuracy when using convolutional neural networks(CNNs).This paper uses a SPECT classification framework with three steps:1)Image denoising,2)Attenuation correction,and 3)Image *** denoising is done by a U-Net architecture that ensures effective image *** correction is implemented by a convolution neural network model that can remove the attenuation that affects the feature extraction process of ***,a novel multi-scale diluted convolution(MSDC)network is *** merges the features extracted in different scales and makes the model learn the features more *** scales of filters with size 3×3 are used to extract *** three steps are compared with state-of-the-art *** proposed denoising architecture ensures a high-quality image with the highest peak signal-to-noise ratio(PSNR)value of *** proposed classification method is compared with the five different CNN models,and the proposed method ensures better classification with an accuracy of 96%,precision of 87%,sensitivity of 87%,specificity of 89%,and F1-score of 87%.To demonstrate the importance of preprocessing,the classification model was analyzed without denoising and attenuation correction.

关键词： SPECT-MPI CAD MSDC denoising attenuation correction classification

Three-Stage Transfer Learning with AlexNet50 for MRI Image Multi-Class Classification with Optimal Learning Rate

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 155-183页

作者： Suganya Athisayamani A.robert Singh Gyanendra Prasad Joshi Woong Cho School of Computing Sastra Deemed to be UniversityThanjavur613401India Department of Computational Intelligence SRM Institute of Science and TechnologyKattankulathur603203India Department of AI and Software Engineering Kangwon National UniversitySamcheok25913Republic of Korea Department of Electronics Information and Communication EngineeringKangwon National UniversitySamcheok25913Republic of Korea

In radiology,magnetic resonance imaging(MRI)is an essential diagnostic tool that provides detailed images of a patient’s anatomical and physiological *** is particularly effective for detecting soft tissue ***,radiologists manually interpret these images,which can be labor-intensive and time-consuming due to the vast amount of *** address this challenge,machine learning,and deep learning approaches can be utilized to improve the accuracy and efficiency of anomaly detection in MRI *** manuscript presents the use of the Deep AlexNet50 model for MRI classification with discriminative learning *** are three stages for learning;in the first stage,the whole dataset is used to learn the *** the second stage,some layers of AlexNet50 are frozen with an augmented dataset,and in the third stage,AlexNet50 with an augmented dataset with the augmented *** method used three publicly available MRI classification datasets:Harvard whole brain atlas(HWBA-dataset),the School of Biomedical Engineering of Southern Medical University(SMU-dataset),and The National Institute of Neuroscience and Hospitals brain MRI dataset(NINS-dataset)for *** hyperparameter optimizers like Adam,stochastic gradient descent(SGD),Root mean square propagation(RMS prop),Adamax,and AdamW have been used to compare the performance of the learning ***-dataset registers maximum classification *** evaluated the performance of the proposed classification model using several quantitative metrics,achieving an average accuracy of 98%.

关键词： MRI tumors classification AlexNet50 transfer learning hyperparameter tuning optimizer

Climate Change:No Going Back

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China Today 2025年第1期74卷 42-44页

作者： robert WALKER Beijing Normal University Royal Society of Arts Academy of Social Sciences in the U.K

With a commitment to reduce emissions,and its investment in green technology bringing down global costs,China is emerging as the leader in fighting climate *** knows that our world is getting *** also know *** out po... 详细信息

关键词： investment bringing fighting

Human endogenous retrovirus type-W and multiple sclerosis–related smoldering neuroinflammation

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Neural Regeneration Research 2025年第3期20卷 813-814页

作者： Joel Gruchot Laura Reiche Andrew Chan robert Hoepner Patrick Küry Department of Neurology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neurology InselspitalBern University Hospital and University of BernBernSwitzerland

Introduction to human endogenous retrovirus type-W(HERV-W): Genomic inheritance from the past includes retroviral sequences that have been stably incorporated into our genomes and account for up to 8% of human DNA.

关键词： endogenous inflammation Human