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Catalytic behavior of Mo-Bi-Fe-Co-K-M-O(M=Ce,Gd,CeGd)catalysts for selective oxidation of isobutene

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Journal of Rare Earths 2024年第1期42卷 84-93,I0003页

作者： Qinghui li Huahua {1. Jian Yang Jun {1. liang Yan Huanling Song lingjun Chou State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China University of chinese academy of sciences Beijing100049China

The further improvement of methacrolein(MAL)selectivity from isobutene(IB)oxidation is crucial and *** this study,based on the typical Mo-Bi-Fe-Co-K-O mixed metal oxide,the rare earth element Gd-doped,Ce-doped and CeGd co-doped catalysts were prepared by co-precipitation strategy to increase the selectivity of MAL from 47.9%to 49.8%,64.2. and 68.6%,*** order to elucidate in-depth the promoting effect of Ce and/or Gd,various characterizations were utilized including X-ray diffraction patterns(XRD),Raman,X-ray fluorescence spectrometry(XRF),X-ray photoelectron spectroscopy(XPS),O_(2.-temperature programmed desorption(O_(2.-TPD),H2.temperature programmed reduction(H2.TPR),CO_(2.-temperature programmed desorption(CO_(2.-TPD),IB-temperature programmed desorption(i-C4-TPD)and in-situ IB-Fourier transform infrared spectroscopy(IB-FTIR).Both Ce and Gd finely regulate the bulk and surface structure of the catalyst,thus altering the redox ability,oxygen mobility and storage ability and *** with Ce,Gd addition slightly regulates the variation of Co^(2.)/Co^(3.)redox couples,greatly enhances the interaction among the components on the catalyst,thus only increases the content of surface oxygen species and has little effect on their *** Cecontaining catalyst performs stronger oxygen storage and migration ability,thus leading to the overproduction of surface Odefectspecies,which are proposed to be the active sites for the production of MAL and *** CeGd co-doped catalyst possesses the proper content of surface Odefectspecies,thus exhibits much higher MAL ***,the promoting mechanism of Ce and/or Gd over IB oxidation is ***,this work is helpful for understanding the influence of rare earth elements on the structure of mixed metal oxides and the olefin selective oxidation reaction.

关键词： Mixed metal oxide catalyst Rare earth element Isobutene Selective oxidation Methacrolein

Enhanced stability of nitrogen-doped carbon-supported palladium catalyst for oxidative carbonylation of phenol

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chinese Journal of Chemical Engineering 2024年第1期65卷 19-28页

作者： Xiaojing liu Ruohan {1. Hao {1. Zhimiao Wang Fang li Wei Xue Yanji Wang Hebei Provincial Key Laboratory of Green Chemical Technology and High Efficient Energy Saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Tianjin Key Laboratory of Chemical Process Safety Tianjin 300130China Hebei Industrial Technology Research institute of Green Chemical Industry Huanghua 061100China

Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and ***,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticles(NPs)on nitrogen-doped carbon;synthesized by using F1.7 as a stabilizer,as well as chitosan as a carbon and nitrogen *** Pd/NCF catalyst was efficient and recyclable for oxidative carbonylation of phenol to diphenyl carbonate,exhibiting higher stability than Pd/NC prepared without F1.7 *** hydrogen bond between chitosan(CTS)and F1.7 was enhanced by F1.7,which anchored the N in the free amino group,increasing the N content of the carbon material and ensuring that the support could provide sufficient N sites for the deposition of Pd *** process helped to improve metal *** increased metal-support interaction,which limits the leaching and coarsening of Pd NPs,improves the stability of the Pd/NCF ***,density functional theory calculations indicated that pyridine N stabilized the Pd^(2.)species,significantly inhibiting the loss of Pd^(2.)in Pd/NCF during the reaction *** work provides a promising avenue towards enhancing the stability of nitrogen-doped carbon-supported metal catalysts.

关键词： Supported Pd catalyst N-doped carbon Amphiphilic triblock copolymer Pyridinic nitrogen Stability

Combining cisplatin and a STING agonist into one molecule for metalloimmunotherapy of cancer

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National Science Review 2024年第1期11卷 107-119页

作者： Shuren Zhang Dongfan Song Wenhao Yu Ji li Xiaoyu Wang Yachao li Zihan {2. Qi Xue Jing {2. Jie P.li Zijian Guo State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringChemistry and Biomedicine Innovation Center (ChemBIC) Nanjing University Department of Urology Afflliated Drum Tower HospitalMedical SchoolNanjing University Nanchuang (Jiangsu)institute of Chemistry and Health

Mounting evidence suggests that strategies combining DNA-damaging agents and stimulator of interferon genes(STING) agonists are promising cancer therapeutic regimens because they can amplify STING activation and remodel the immunosuppressive tumor microenvironment. However, a single molecular entity comprising both agents has not yet been developed. Herein, we designed two PtIV-MSA-2.conjugates(Ⅰand Ⅱ) containing the DNA-damaging chemotherapeutic drug cisplatin and the innate immuneactivating STING agonist MSA-2. these conjugates showed great potential as multispecific small-molecule drugs against pancreatic cancer. Mechanistic studies revealed that conjugate Ⅰ upregulated the expression of transcripts associated with innate immunity and metabolism in cancer cells, significantly differing from cisplatin and MSA-2. An analysis of the tumor microenvironment demonstrated that conjugate I could enhance the infiltration of natural killer(NK) cells into tumors and promote the activation of T cells, NK cells and dendritic cells in tumor tissues. These findings indicated that conjugate I, which was created by incorporating a Pt chemotherapeutic drug and STING agonist into one molecule, is a promising and potent anticancer drug candidate, opening new avenues for small-molecule-based cancer metalloimmunotherapy.

关键词： platinum drug STING agonist single-molecule multitarget metalloimmunology

Sorption of Eu^(3.) onto nano-size silica-water interfaces

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Science China Earth sciences 2005年第11期48卷 1942-1948页

作者： HU Ping1.2. YIN Xiulan3., zhao {1.nghu1.& {1. Dien4 1. Department of Earth sciences, China University of Geosciences, Wuhan 43.074, China 2. Northeastern Il{1.nois University, Chicago, IL 6062., USA 3. China {3. of Geo-Environmental Monitoring, Beijing 1.0081. China 4. Division of Chemistry, Los Alamos National Laboratory, Los Alamos, NM 87544, USA 1. Department of Earth sciences China University of Geosciences 430074 Wuhan China 2. Northeastern Illinois University 60625 Chicago IL USA 3. China institute of Geo-Environmental Monitoring 100081 Beijing China 4. Division of Chemistry Los Alamos National Laboratory 87544 Los Alamos NM USA

The sorption of Eu species onto nano-size silica-water interfaces is investigated at pH range of 1.8.5 and the initial Eu concentrations (CEu) of 2.× 1.?5, 2.× 1.?4 and 2.× 1.?3.M using fluorescence spectroscopy. The sorption rate of Eu is initially low, but significantly in-creases at pH > 4. For the initial CEu of 2.× 1.?5, 2.× 1.?4 and 2.× 1.?3.M, the dissolved Eu spe-cies are completely sorbed onto silica-water interfaces at pH = 4.75, ~5.8 and 6.6, respectively, with the respective sorption densities of ~1.58 × 1.?8, 1.58 × 1.?7 and 1.58 × 1.?6 mol/m2. The sorbed Eu species at pH 3., which is sorbed onto silica-water interfaces as an outer-sphere complex at pH 2. to ~6 at pH = 6. At pH = 6 – 8, Eu(OH)2., Eu(CO3.+ and Eu(CO3.2. form in the solutions, and Eu(CO3.+ is dominant at pH = ~7.5. These ions may be sorbed onto silica-water interfaces as inner-sphere bidentate complexes or multi-nuclear pre-cipitates.

关键词： surface sorption, Eu3. species, nano-size silica, fluorescence spectroscopy, immobilization of toxic metals

Security and Privacy in Solar Insecticidal Lamps Internet of Things:Requirements and Challenges

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 58-73页

作者： Qingsong zhao Lei Shu Kai{1.ang {1. Mohamed Amine Ferrag Ximeng {1.u Yanbin {1. the College of Artificial Intelligence Nanjing Agricultural UniversityNanjing 210031 the State Key Laboratory for Novel software Technology Nanjing UniversityNanjing 210023 the State Key Laboratory of Cryptology Beijing 100878China IEEE the School of Engineering University of LincolnLincoln LN67TSUK the Artificial Intelligence and Digital Science Research Center Technology Innovation InstituteMasdar City 9639UAE the College of Computer and Data Science Fuzhou UniversityFuzhou 350108China

Solar insecticidal lamps(SIL) can effectively control pests and reduce the use of pesticides. Combining SIL and Internet of Things(IoT) has formed a new type of agricultural IoT,known as SIL-IoT, which can improve the effectiveness of migratory phototropic pest control. However, since the SIL is connected to the Internet, it is vulnerable to various security *** issues can lead to serious consequences, such as tampering with the parameters of SIL, illegally starting and stopping SIL,etc. In this paper, we describe the overall security requirements of SIL-IoT and present an extensive survey of security and privacy solutions for SIL-IoT. We investigate the background and logical architecture of SIL-IoT, discuss SIL-IoT security scenarios, and analyze potential attacks. Starting from the security requirements of SIL-IoT we divide them into six categories, namely privacy, authentication, confidentiality, access control, availability,and integrity. Next, we describe the SIL-IoT privacy and security solutions, as well as the blockchain-based solutions. Based on the current survey, we finally discuss the challenges and future research directions of SIL-IoT.

关键词： Challenges Internet of Things(IoT) privacy and security security requirements solar insecticidal lamps(SIL)

Advanced System-Level Model Reduction Method for Multi-Converter DC Power Systems

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1550-1562页

作者： lin Zhu Xueshen {1. Xialin li li Guo Bo {1. Zhanfeng Deng Hao Lu Chengshan Wang the Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072China the Research institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310014China the State Grid Global Energy Interconnection Research institute Beijing 102209China

For dynamic stability analysis and instability mechanism understanding of multi-converter medium voltage DC power systems with droop-based double-loop control,an advanced system-level model reduction method is *** this method,mathematical relationships of control parameters(e.g.,current and voltage control parameters)between the system and its equivalent reduced-order model are ***,open-loop and closed-loop equivalent reduced-order models of current control loop considering dynamic interaction among converters are *** instability mechanism(e.g.,unreasonable current control parameters)of the system can be revealed *** guidance for adjustment of current control parameters can also be ***,considering dynamic interaction of current control among converters,open-loop and closed-loop equivalent reduced-order models of voltage control loop are *** frequency and damping factor of DC bus voltage in a wide oscillation frequency range(e.g.,{3.–50 Hz)can be evaluated *** importantly,accuracy of advanced system-level model reduction method is not compromised,even for MVDC power systems with inconsistent control parameters and different number of ***,experiments in RT-BOX hardware-in-the-loop experimental platform are conducted to validate the advanced system-level model reduction method.

关键词： Closed-loop reduced-order model instability mechanism open-loop reduced-order model stability analysis system-level model reduction method

All-dielectric terahertz metasurface governed by bound states in the continuum with high-Q factor

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 44-54页

作者： li Kun {1. Xu Wang Meng Jia Xingning {1. Ruiqi Lu Guizhen School of Integrated Circuit Science and Engineering Tianjin University of TechnologyTianjin 300384China School of Electronic and Electrical Engineering Ningxia UniversityYinchuan 750021China QILU Aerospace Information Research institute Chinese Academy of Sciences(CAS)Jinan 250101China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing 100024China

The method of terahertz(THz)resonance with a high-quality(high-Q)factor offers a vital physical mechanism for metasurface sensors and other high-Q factor ***,it is challenging to excite the resonance with a high-Q factor in metasurfaces with proper sensitivity as well as figure of merit(FOM)***,an all-dielectric metasurface composed of two asymmetrical rectangular blocks is *** and silicon are the materials applied for the substrate and cuboids *** distinct resonance governed by bound states in the continuum(BIC)is excited by forming an asymmetric cluster by a novel hybrid method of cutting and moving the *** investigation focuses on analyzing the transmission spectra of the metasurface under different variations in structural parameters and the loss of silicon refractive *** the proposed defective metasurface serves as a transmittance sensor,it shows a Q factor of 1.08×1.^(4)and achieves an FOM up to 4.8×1.^(6),which is obtained under the asymmetric parameter equalling 1.***,the proposed defective metasurface is sensitive to small changes in refractive *** the thickness of the analyte is 1.0μm,the sensitivity reaches a maximum value of 578 GHz/***,the proposed defective metasurface exhibits an extensive number of possible applications in the filters,biomedical diagnosis,security screening,and so on.

关键词： terahertz(THz)metasurface high-quality(high-Q)factor bound states in the continuum figure of merit(FOM)

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： li Guoxia1. {1. Weijuan1. li Rongwu2. SUN Hongwei1. GUO Min1. WANG Yanfang1. liU Hui1. {1. Qingyun3. SUN Xinmin3. {1. Wenjun3.& CHENG Huansheng4 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 450052. China 2. Department of Physics, Beijing Normal University, Beijing 1.0875, China 3. {3. of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, China 4. {3. of Modern Physics, Fudan University, Shanghai 2.043., China Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of Physics Beijing Normal University Beijing 100875 China institute of Cultural Re{1.c Archaeology of Henan Province Zhengzhou 450000 China institute of Modern Physics Fudan University Shanghai 200433 China

3. samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

Global hydraulic stability analysis for dynamic regulation in multi-zone variable air volume air-conditioning system

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Energy and Built Environment 2024年第4期5卷 592-606页

作者： Tianyi zhao Zhe {1. Xiuming {1. Hong{1.an Peng institute of Building Energy School of Civil EngineeringFaculty of Infrastructure EngineeringDalian University of TechnologyDalian 116024China Anhui Province Key Laboratory of Intelligent Building&Building Energy Saving Anhui Jianzhu UniversityHefei 230022China School of Metallurgy Northeastern UniversityShenyang 110819China School of Architecture Harbin Institute of TechnologyHarbin150006China

Variable air volume air-conditioning system(VAV system)has multiple control loops that interfered with each other,which has serious impacts on its actual operation *** solve this problem,the index of global hydraulic stability,which takes the physical quantity of the pipe network pressure and the air flow rate as reference,is proposed based on Graph theory,and a pipe network model for the hydraulic calculation is ***,the simulation study based on the actual operation data is carried out in *** distribution of the pressure and the air flow in the pipe network is obtained,and the action interferences among adjacent terminal boxes are analyzed based on global hydraulic stability under damper position regulation strategy(DP strategy)and fan frequency regulation strategy(FF strategy).Results indicate that the FF strategy can decrease the total change distance of the damper position compared with the DP strategy,and then the fluctuation of the pressure and the air flow can be *** contribution of this study is to provide an evaluation index of global hydraulic stability,which can also be used in other air-conditioning systems with multiple terminals and multiple control loops.

关键词： VAV system Global hydraulic stability Adjustment strategy VAV box damper position