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Phosphine-Catalyzed [4+3] Annulation Reaction of Indole Derivatives with MBH Carbonates:A Facile Access to Indole-1,2-fused 1,4-Diazepinones and Azepines

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Chinese Journal of Chemistry 2024年第3期42卷 271-275页

作者： Yannan Zhu Haoran Jiang Yi-Ning Wang faculty of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYanchengJiangsu224051 China

A phosphine-catalyzed [4+3] annulation between dinucleophilic indole derivatives and Morita−Baylis−Hillman (MBH) carbonates was discovered by using the N1 and N4′/C4′ nucleophilicities of the indole precursors,in which indoles act as four atom synthons. This protocol provides an efficient and facile access to indole-1,2-fused 1,4-diazepinones and azepines in good to high yields in one step,which illustrates potential synthetic utilities in drug discovery.

关键词： Phosphine catalysis [4+3]Annulation Indole derivatives Nitrogen heterocycles Organocatalysis

A short review of antibacterial Cu-bearing stainless steel:antibacterial mechanisms,corrosion resistance,and novel preparation techniques

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Journal of Iron and Steel Research International 2024年第1期31卷 24-45页

作者： Shuai Liu Han-jie Guo School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology BeijingBeijing100083China

Cu-bearing stainless steel is widely used in the fields of food,medical and household sanitary equipment because of its surface finish and corrosion ***,the growth of bacteria on stainless steel leads to the formation of biofilms,which causes ***,the antibacterial property of stainless steel is a worthy research *** of breakthroughs in the field of corrosion resistance and antimicrobial properties are still ***,due to the scarcity of publications on the antibacterial mechanisms and processing methods of antibacterial Cu-bearing stainless steel,we review the current state of relevant research and *** toxicity of Cu,corrosion resistance mechanism of stainless steel,and antibacterial mechanism and preparation method of antibacterial stainless steel are *** addition,alloying,surface modification and other methods are found to have limitations in balancing the toxicity and antibacterial properties of copper and the relationship between the antibacterial properties and corrosion resistance of Cu-bearing stainless steel.A new preparation method of antibacterial stainless steel associated with selective laser melting(SLM)is *** is becoming a powerful additive manufacturing technology that can be used to manufacture customized and complex *** research status of SLM applied in antibacterial stainless steel preparation is ***,the future research direction of Cu-bearing antibacterial stainless steel is discussed.

关键词： Cu-bearing stainless steel Antibacterial Processing Additive manufacturing Corrosion resistance

Integrated transcriptomics and metabolomics analysis reveal the molecular mechanism of unsaponifiable matter in delaying aging

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Food Science and Human Wellness 2024年

作者： Dan Hong Aijin Ma Xiao Xiao Mengge Ma Zhou Chen Siting Li Yingmin Jia School of Food and Health， Beijing technology and business University

Aging is one of the causes of cognitive dysfunction， which seriously affects people's quality of life. Unsaponifiable matter (USM) has antioxidant potential， but the molecular mechanisms that ameliorate aging and cognitive dysfunction are unknown. In this study， we used a galactose-induced brain aging mouse model and systematically analyzed the mechanism of USM in delaying aging in mice by detecting changes in serum and brain by metabolomics and *** was compared with the model group， and non-targeted metabolomics identified 68 (15 up- regulated，53down-regulated) differentially metabolites，andtranscriptomics identified 303 differentially expressed genes (228 up-regulated， 75 down-regulated). Combined multi-omics analyses showed that USM maintains normal brain function by regulating glycolytic processes， the tricarboxylic acid cycle (TCA)， tryptophan metabolism， pyrimidine metabolism， the alanine， aspartate， and glutamate metabolism， and P38MAPK pathway. Meanwhile， USM increased neurotransmitter release from GABAergic synapses and cholinergic synapses by regulating synaptic vesicle cycling. In summary， USM increased energy metabolism and enhanced brain nerve signaling in the mouse brain， thereby delaying brain aging. This investigation offers novel perspectives into the molecular mechanism of USM to mitigate brain aging.

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Zonal activation of molecular carbon dioxide and hydrogen over dual sites Ni-Co-MgO catalyst for CO_(2) methanation:Synergistic catalysis of Ni and Co species

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Journal of Energy Chemistry 2024年第4期91卷 213-225页

作者： Zonglin Li Jianjun Chen Yu Xie Junjie Wen Huiling Weng Mingxue Wang Jingyi Zhang Jinyan Cao Guocai Tian Qiulin Zhang Ping Ning faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500YunnanChina National-Regional Engineering Center for Recovery of Waste Gases from Metallurgical and Chemical Industries Kunming University of Science and TechnologyKunming 650500YunnanChina faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina

An in-depth mechanism in zonal activation of CO_(2)and H2molecular over dual-active sites has not been revealed ***,Ni-Co-MgO was rationally constructed to elucidate the CO_(2)methanation *** abundant surface nickel and cobalt components as active sites led to strong Ni-Co interaction with charge transfer from nickel to ***,electron-enriched Coδ-species participated in efficient chemisorption and activation of CO_(2)to generate monodentate ***,plentiful available Ni0sites facilitated H2dissociation,thus CO_(2)and H2were smoothly activated at zones of Coδ-species and Ni0,*** in situ DRIFTS,quasi situ XPS,TPSR,and DFT calculations substantiated a new formate evolution mechanism via monodentate carbonate instead of traditional bidentate carbonate based on synergistic catalysis of Coδ-species and *** zonal activation of CO_(2)and H2by tuning electron behaviors of double-center catalysts can boost heterogeneous catalytic hydrogenation performance.

关键词： Zonal activation CO_(2) methanation Dual active sites Synergistic effect

Food-derived protein hydrolysates and peptides:anxiolytic and antidepressant activities,characteristics,and mechanisms

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Food Science and Human Wellness 2024年第3期13卷 1168-1185页

作者： Wenhui Li Yu Xi Junru Wang Yinxiao Zhang He Li Xinqi Liu Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Engineering and Technology Research Center of Food AdditivesNational Soybean Processing Industry Technology Innovation CenterBeijing Technology and Business UniversityBeijing 100048China

Globally,the prevalence of anxiety and depression has reached epidemic ***-derived protein hydrolysates and peptides delivered through dietary supplementation can avoid the negative risks associated with traditional pharmaceuticals while delivering superior anxiolytic and antidepressant *** review summarizes current research on food-derived anxiolytic and antidepressant protein hydrolysates and peptides,and subsequently analyses their physicochemical characteristics and elaborates on their *** aim of this work is to contribute to the in-depth study and provide a theoretical foundation for the development of related products to better serve patients with anxiety and depression.

关键词： Anxiolytic Antidepressant Peptides Protein hydrolysates Neurotransmitter

Innovations in metallurgical and materials processes:advancing liquid theory and honoring ***-jie Guo's contributions to physical chemistry in metallurgy

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Journal of Iron and Steel Research International 2024年第1期31卷 1-2页

作者： Shuai Liu Jing Guo Han-jie Guo School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China

Spanning three decades,***-jie Guo's research group has dedicated itself to exploring the fundamental theories and practical applications of physical chemistry within the realm of *** under the assumption that molecul... 详细信息

关键词： chemistry liquid complexes

Adaptive Optimal Discrete-Time Output-Feedback Using an Internal Model Principle and Adaptive Dynamic Programming

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 131-140页

作者： Zhongyang Wang Youqing Wang Zdzisław Kowalczuk the College of Information Science and technology Beijing University of Chemical TechnologyBeijing 100029China IEEE the Department of Robotics and Decision Systems Faculty of ElectronicsTelecommunications and InformaticsGdańsk University of TechnologyGdansk 80-233Poland

In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed method, termed as IMP-ADP, does not require complete state feedback-merely the measurement of input and output data. More specifically, based on the IMP, the output control problem can first be converted into a stabilization problem. We then design an observer to reproduce the full state of the system by measuring the inputs and outputs. Moreover, this technique includes both a policy iteration algorithm and a value iteration algorithm to determine the optimal feedback gain without using a dynamic system model. It is important that with this concept one does not need to solve the regulator equation. Finally, this control method was tested on an inverter system of grid-connected LCLs to demonstrate that the proposed method provides the desired performance in terms of both tracking and disturbance rejection.

关键词： Adaptive dynamic programming(ADP) internal model principle(IMP) output feedback problem policy iteration(PI) value iteration(VI)

Intelligent Machine Learning Based Brain Tumor Segmentation through Multi-Layer Hybrid U-Net with CNN Feature Integration

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Computers, Materials & Continua 2024年第4期79卷 1301-1317页

作者： Sharaf J.Malebary Department of Information technology Faculty of Computing and Information TechnologyKing Abdulaziz UniversityP.O.Box 344Rabigh21911Saudia Arabia

Brain tumors are a pressing public health concern, characterized by their high mortality and morbidity ***, the manual segmentation of brain tumors remains a laborious and error-prone task, necessitatingthe development of more precise and efficient methodologies. To address this formidable challenge, we proposean advanced approach for segmenting brain tumorMagnetic Resonance Imaging (MRI) images that harnesses theformidable capabilities of deep learning and convolutional neural networks (CNNs). While CNN-based methodshave displayed promise in the realm of brain tumor segmentation, the intricate nature of these tumors, markedby irregular shapes, varying sizes, uneven distribution, and limited available data, poses substantial obstacles toachieving accurate semantic segmentation. In our study, we introduce a pioneering Hybrid U-Net framework thatseamlessly integrates the U-Net and CNN architectures to surmount these challenges. Our proposed approachencompasses preprocessing steps that enhance image visualization, a customized layered U-Net model tailoredfor precise segmentation, and the inclusion of dropout layers to mitigate overfitting during the training ***, we leverage the CNN mechanism to exploit contextual information within brain tumorMRI images,resulting in a substantial enhancement in segmentation *** experimental results attest to the exceptionalperformance of our framework, with accuracy rates surpassing 97% across diverse datasets, showcasing therobustness and effectiveness of our approach. Furthermore, we conduct a comprehensive assessment of ourmethod’s capabilities by evaluating various performance measures, including the sensitivity, Jaccard-index, andspecificity. Our proposed model achieved 99% accuracy. The implications of our findings are profound. Theproposed Hybrid U-Net model emerges as a highly promising diagnostic tool, poised to revolutionize brain tumorimage segmentation for radiologists and clinician

关键词： Brain tumor Hybrid U-Net CLAHE transfer learning MRI images

Characterization and Selection of Microcrystalline Cellulose from Oil Palm Empty Fruit Bunches for Strengthening Hydrogel Films

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Journal of Renewable Materials 2024年第3期12卷 513-537页

作者： Susi Susi Makhmudun Ainuri Wagiman Wagiman Mohammad Affan Fajar Falah Department of Agroindustrial technology Faculty of AgricultureUniversitas Lambung MangkuratJl A Yani Km 36BanjarbaruSouth Kalimantan70714Indonesia Doctoral Programme of Agroindustrial technology Faculty of Agricultural TechnologyUniversitas Gadjah MadaJl Flora No.1BulaksumurYogyakarta55281Indonesia Department of Agroindustrial technology Faculty of Agricultural TechnologyUniversitas Gadjah MadaJl Flora No.1BulaksumurYogyakarta55281Indonesia

Microcrystalline cellulose(MCC)is one of the cellulose derivatives produced as a result of the depolymerization of a part of cellulose to achieve high *** implemented in other polymers,high crystallinity correlates with greater strength and stiffnes,but it can reduce the water-holding *** acid concentration and hydrolysis time will affect the acquisition of crystallinity and water absorption capacity,both of which have significance as properties of hydrogel *** study aimed to evaluate the properties and select the MCC generated from varying the proportion of hydrochloric acid(HCl)and the appropriate hydrolysis time as a filler for film *** was produced by hydrolyzing cellulose of oil palm empty fruit bunches(OPEFB)with the HCl solution at varied concentrations and *** results show that the longer hydrolysis times and higher HCl concentrations increase crystallinity and density while lowering yield and water *** extensive acid hydrolysis reduces the amorphous area significantly,allowing the depolymerization to occur and extend the crystalline *** morphological properties of the MCC,which are smaller but compact,indicate the presence of disintegrating and diminishing structures.A 2.5 N HCl concentration and a 45-min hydrolysis time succeed in sufficient crystallinity as well as maintaining good water absorption *** treatment produced MCC with absorption capacity of 4.03±0.26 g/g,swelling capacity of 5.03±0.26 g/g,loss on drying of 1.44%±0.36,bulk and tapped density of 0.27±0.031 g/cm^(3) and 0.3±0.006 g/cm^(3),respectively,with a crystallinity index of 88.89%±4.76 and a crystallite size of 4.23±0.70 *** MCC generated could potentially be utilized as a hydrogel film filler,since a given proportion will be able to maintain the strength of the hydrogel,not readily dissolve but absorb water significantly.

关键词： Acid hydrolysis hydrogel OPEFB microcrystalline cellulose water absorption