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Peracetic acid catalytic activation using Co3O4 nanocluster decorated graphitic carbon nitride for cefapirin degradation in water

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Science China Technological Sciences 2024年第10期67卷 3103-3115页

作者： YIN ShiMei GAO YiXuan CHEN Long LI Fan liu XiaoNa QI Fei liu wen Beijing Key Lab for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry University Key Laboratory of Water and Sediment Sciences (Ministry of Education) College of Environmental Sciences and EngineeringPeking University School of Environmental Science and Engineering Taiyuan University of Technology State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems Peking University Beijing National Laboratory for Molecular Sciences Peking University

This study innovated cobalt-based catalytic nanocomposites（CCNs） for the heterogeneous activation of peracetic acid（PAA）,a green and efficient advanced oxidation process for removing antibiotics from *** Co3O4catalysts exhibit limited activity due to stable electronic *** overcome this,CCNs were synthesized using a one-step condensation method,incorporating a size control strategy that anchors Co3O4nanoclusters within 4-5 nm onto six-fold cavity of g-C3N4,simultaneously modifying the coordination environment of *** alteration significantly enhances the adsorption energy of PAA and catalytic activity compared to commercial *** improved performance of CCN2,in particular,is attributed to a shift in the cobalt d band center towards the Fermi level,facilitating electron delocalization and transfer,enhancing Co-O bonding,and accelerating PAA ***2's superior activity,with a cefapirin（CFP） degradation kinetic rate constant(k1=0.760 min-1)～11 times that of PAA direct oxidation(k1=0.070 min-1) and～5 times that of commercial Co3O4/PAA system(k1=0.164 min-1),is due to its ability to generate dominant reactive species for antibiotic degradation,including alkoxy radicals(CH3C（=O）OO·),high valence metal(CoⅣ（=O）2+),and singlet oxygen（1O2）,with the latter two being crucial for the degradation *** degradation of CFP involved three mechanisms,including direct oxidation by PAA,decarboxylation,and open-ring reactions at nitrogen *** research provides insights into developing high-activity catalysts for efficient PAA activation and antibiotic removal,leveraging the strategy of shifting the transition metal d band center.

关键词： peracetic acid Co3O4 nanocluster high valence metal singlet oxygen cefapirin

QBIoT:A Quantum Blockchain Framework for IoT with an Improved Proof-of-Authority Consensus Algorithm and a Public-Key Quantum Signature

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Computers, Materials & Continua 2024年第7期80卷 1727-1751页

作者： Ang liu Qing Zhang Shengwei Xu Huamin Feng Xiu-bo Chen wen liu Network and Information Management Division Beijing Electronic Science and Technology InstituteBeijing100070China Department of Cyberspace Security Beijing Electronic Science and Technology InstituteBeijing100070China Information Security Institute Beijing Electronic Science and Technology InstituteBeijing100070China General Office Beijing Electronic Science and Technology InstituteBeijing100070China Information Security Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China

The Internet of Things(IoT)is a network system that connects physical devices through the Internet,allowing them to ***,IoT has become an integral part of our lives,offering convenience and smart ***,the growing number of IoT devices has brought about a corresponding increase in cybersecurity threats,such as device vulnerabilities,data privacy concerns,and network *** blockchain technology with IoT has proven to be a promising approach to enhance IoT ***,the emergence of quantum computing poses a significant challenge to the security of traditional classical cryptography used in blockchain,potentially exposing it to quantum *** support the growth of the IoT industry,mitigate quantum threats,and safeguard IoT data,this study proposes a robust blockchain solution for IoT that incorporates both classical and post-quantum security ***,we present the Quantum-Enhanced Blockchain Architecture for IoT(QBIoT)to ensure secure data sharing and integrity ***,we propose an improved Proof of Authority consensus algorithm called“Proof of Authority with Random Election”(PoARE),implemented within QBIoT for leader selection and new block ***,we develop a publickey quantum signature protocol for transaction verification in the ***,a comprehensive security analysis of QBIoT demonstrates its resilience against cyber threats from both classical and quantum *** summary,this research introduces an innovative quantum-enhanced blockchain solution to address quantum security concernswithin the realmof *** proposedQBIoT framework contributes to the ongoing development of quantum blockchain technology and offers valuable insights for future research on IoT security.

关键词： IoT quantum blockchain public-key quantum signature quantum hash function

A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

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China Ocean Engineering 2024年第2期38卷 233-246页

作者： DING Xin-dong WANG Shu-qing liu wen-cheng YE Xiao-han College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Department of Marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water *** investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are *** the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary *** for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with *** has been observed that the cross-section of the middle part collapses when it reaches the maximum *** collapse pressure obtained from the numerical simulations agrees well with that in the ***,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also *** has a relatively greater difference because of the ignorance of the progressive failure of *** the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality

Divergent defluorocarboxylation of α-CF_(3) alkenes with formate via photocatalyzed selective mono-or triple C-F bond cleavage

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Science China Chemistry 2024年第1期67卷 368-373页

作者： Xing-Yu Wang Pei Xu wen-wen liu Hao-Qiang Jiang Song-Lei Zhu Dong Guo Xu Zhu Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy School of PharmacyXuzhou Medical UniversityXuzhou 22100China

Unprecedented divergent synthesis of gem-difluorovinylacetic acid and glutaric acid derivatives fromα-CF_(3)alkenes with formate as the carbonyl source was *** reaction can undergo selective mono-or triple C-F bond cleavage by simply switching the photocatalyst and hydrogen atom transfer(HAT)catalyst under visible-light-induced conditions at room *** acts as both the C1 source and the reductant through the generation of CO_(2)^(·-)species,which underwent Giese radical addition to electron-deficient alkenes to trigger the consecutive C-F bond cleavage and carboxylation process.

关键词： C-F bond activation defluorocarboxylation carbon dioxide radical anion visible light

The centrosymmetric to non-centrosymmetric transformation induced by alkaline-earth cations producing infrared nonlinear optical AeMn_(6)Ga_(6)S_(16)(Ae=Ca,Sr)

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Science China Chemistry 2024年第9期67卷 2941-2948页

作者： Yang-Ping Zhang Shao-Min Pei wen-Fa Chen Bin-wen liu Xiao-Ming Jiang Guo-Cong Guo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China

Non-centrosymmetric(NCS)structure is an indispensable prerequisite for second-order nonlinear optical(NLO)***,the mainstream approach for designing new NCS structures still relies on chemical substitution,necessitating an urgent infusion of fresh *** this work,two isomorphic sulfides AeMn_(6)Ga_(6)S_(16)(Ae=Ca,1;Sr,2)are afforded by modifying the skeleton of centrosymmetric(CS)Mn_(2)Ga_(2)S_(5) via introducing strong electropositive alkaline-earth ***,the incorporation of Ca^(2+)/Sr^(2+)cations allows the elementary[MnGaS_(9)]_(∞)chains to reconfigure into bumpy[MnS_(6)]-[GaS_(4)]layers in a new engagement manner,thus enabling the conversion from CS to NCS *** modifications cause not only strong second-harmonic generation(SHG)responses(~1.5×benchmark AgGaS_(2)@1,700 nm),but also significantly feasible bandgaps(2.60-2.64 e V)compared to the sulfide Mn_(2)Ga_(2)S_(5)(1.36 e V),which ultimately facilitate ultrahigh laser-induced damage thresholds(4.4-6.6×AgGaS_(2)@1,064 nm for compounds 1 and 2).The present study offers an ingenious approach for the transformation of CS to NCS structure.

关键词： second-harmonic generation non-centrosymmetrical structure NLO functional motif solid-state method

Bioinspired zinc-mediated umpolung thiolation of alkyl electrophiles: reaction development, scope and mechanism

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Science China Chemistry 2024年第3期67卷 898-907页

作者： Yuenian Xu Yan Zhang Yong liu wen-Wu Sun Jie Huang Hui He Yingjie Wu wen liu Shao-Fei Ni Xu-Qiong Xiao Xinxin Shao College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China School of Pharmaceutical Sciences South-Central Minzu UniversityWuhan 430074China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province Shantou UniversityShantou 515063China

Zinc-promoted umpolung thiolation of alkyl electrophiles with masked sulfur transfer reagents in the absence of nickel or copper catalysis is described. This protocol proceeds via a SET process of Zn to electrophilic sulfur reagent followed by insertion of Zn into disulfide and nucleophilic thiolation, providing straightforward access to a wide range of alkyl sulfides with broad substrate scope. A neutral TMEDA-ligated four-coordinated zinc thiolate with tetrahedra geometry was synthesized, isolated and fully characterized by NMR, IR and X-ray analysis. More importantly, the chemical reactivity of this active intermediate has been investigated, enabling the construction of C-Se, C-Te, Sb-S and Bi-S bonds to prepare valuable sulfur-containing molecules and beyond.

关键词： umpolung thiolation C(sp^(3))-S bond formation masked sulfur reagents reductive coupling

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An Approximation Algorithm for the Parallel-Machine Customer Order Scheduling with Delivery Time and Submodular Rejection Penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 495-504页

作者： Hong-Ye Zheng Suo-Gang Gao wen liu Bo Hou School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024HebeiChina

In this paper,we consider the parallel-machine customer order scheduling with delivery time and submodular rejection *** this problem,we are given m dedicated machines in parallel and n customer *** order has a delivery time and consists of m product types and each product type should be manufactured on a dedicated *** order is either rejected,in which case a rejection penalty has to be paid,or accepted and manufactured on the m dedicated *** objective is to find a solution to minimize the sum of the maximum delivery completion time of the accepted orders and the penalty of the rejected orders which is determined by a submodular *** design an LP rounding algorithm with approximation ratio of n+1 for this problem.

关键词： Order scheduling Delivery time Submodular rejection penalty Approximation algorithm

Exploiting blockchain for dependable services in zero-trust vehicular networks

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Frontiers of Computer Science 2024年第2期18卷 157-166页

作者： Min HAO Beihai TAN Siming WANG Rong YU Ryan wen liu Lisu YU School of Automation Guangdong University of TechnologyGuangzhou 510006China School of Integrated Circuits Guangdong University of TechnologyGuangzhou 510006China School of Navigation Wuhan University of TechnologyWuhan 430063China School of Information Engineering Nanchang UniversityNanchang 330031China

The sixth-generation(6G)wireless communication system is envisioned be cable of providing highly dependable services by integrating with native reliable and trustworthy ***-trust vehicular networks is one of the typical scenarios for 6G dependable *** the technical framework of vehicle-and-roadside collaboration,more and more on-board devices and roadside infrastructures will communicate for information *** reliability and security of the vehicle-and-roadside collaboration will directly affect the transportation *** a zero-trust vehicular environment,to prevent malicious vehicles from uploading false or invalid information,we propose a malicious vehicle identity disclosure approach based on the Shamir secret sharing ***,a two-layer consortium blockchain architecture and smart contracts are designed to protect the identity and privacy of benign vehicles as well as the security of their private *** that,in order to improve the efficiency of vehicle identity disclosure,we present an inspection policy based on zero-sum game theory and a roadside unit incentive mechanism jointly using contract theory and subjective logic *** verify the performance of the entire zero-trust solution through extensive simulation *** the premise of protecting the vehicle privacy,our solution is demonstrated to significantly improve the reliability and security of 6G vehicular networks.

关键词： sixth-generation(6G) zero-trust block-chain vehicular networks privacy preservation

A Composite Elastomer with Photo-responsive Shape Memory and Programmable Hygroscopic Actuation Functionalities

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Chinese Journal of Polymer Science 2024年第10期42卷 1470-1478,I0009页

作者： Xiang-Xi Cui Li Shang Zhong-wen liu Zhao-Tie liu Jin-Qiang Jiang Guo Li Key Laboratory of Syngas Conversion of Shaanxi Province School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an710062China

Developing hydroscopic actuators with simultaneous high elasticity,shape programmability and tunable actuating behaviors are highly desired but still *** this study,we propose an orthogonal composite design to develop such a *** developed composite elastomer comprises carboxyl group-grafted polystyrene-block-poly(ethylene-co-butylene)-block-polystyrene(SEBS-g-COOH)as the elastic substrate,and a synthesized azobenzene derivative as the functional filler(Azo12).By surface treatment using acidic and base solutions,the carboxyl groups on the surface can reversibly transform into carboxylate groups,which render the composite tunable hygroscopic actuating *** another aspect,the added filler undergoes trans-to-cis isomerization when exposed to UV light irradiation,leading to liquefaction of the crystalline aggregates formed by Azo12 *** liquefied Azo12 molecules can autonomously resotre their trans form and reform the crystalline *** reversible change in crystralline structure is utilized to realize the shape memory property,and 5 wt%of Azo12addition is adequate for the composite to exhibit photo-responsive shape memory behavior without compromising much of the *** regualtion of external geometry by shape memory effect is effective in altering the actuating *** proposed method can be extend to designing different composites with the demonstrated functionalities.

关键词： Actuator Shape memory Photo-responsive Hygroscopic responsive Azobenzene