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Different coalescence sources of light nucleus production in Au-Au collisions at √sNN=3 GeV

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Chinese Physics C 2024年第5期48卷 160-179页

作者：王瑞芹吕济鹏李彦豪宋军邵凤兰 school of Physics and physical engineering Qufu Normal UniversityQufu 273165China school of physical science and Intelligent engineering Jining UniversityJining 273155China

We study the production of light nuclei in the coalescence mechanism of Au-Au collisions at midrapidity at √sNN=3GeV.We derive analytic formulas of the momentum distributions of two bodies,three bodies,and four nucleons coalescing into light nuclei and naturally explain the transverse momentum spectra of the deuteron(d),triton(t),helium-3(3He),and helium-4(4He).We reproduce data on the yield rapidity densities,yield ratios,and averaged transverse momenta of d,t,3He,and 4He and provide the proportions of contributions from different coalescence sources for t,3He,and 4He in their production.We find that besides nucleon coalescence,nucleon+nucleus coalescence and nucleus+nucleus coalescence may play requisite roles in light nucleus production in Au-Au collisions at √sNN=3 GeV.

关键词： light nucleus production the coalescence model relativistic heavy ion collision

Conductive catalysis by subsurface transition metals

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National science Review 2024年第1期11卷 86-93页

作者： Xin Deng Caiyan Zheng Yangsheng Li Zeyu Zhou Jiamin Wang Yihua Ran Zhenpeng Hu Fan Yang Landong Li Frontiers science Center for New Organic Matter College of ChemistryNankai University school of Physics Nankai University school of physical science and Technology Shanghai Tech University school of Materials science and engineering Nankai University Haihe Laboratory of Sustainable Chemical Transformations

The nature of catalysis has been hotly pursued for over a century, and current research is focused on understanding active centers and their electronic structures. Herein, the concept of conductive catalysis is proposed and verified by theoretical simulations and experimental observations. Metallic systems containing buried catalytically active transitional metals and exposed catalytically inert main group metals are constructed, and the electronic interaction between them via metallic bonding is disclosed. Through the electronic interaction, the catalytic properties of subsurface transitional metals(Pd or Rh) can be transferred to outermost main group metals(Al or Mg) for several important transformations like semi-hydrogenation,Suzuki-coupling and hydroformylation. The catalytic force is conductive, in analogy with the magnetic force and electrostatic force. The traditional definition of active centers is challenged by the concept of conductive catalysis and the electronic nature of catalysis is more easily understood. It might provide new opportunities for shielding traditional active centers against poisoning or leaching and allow for precise regulation of their catalytic properties by the conductive layer.

关键词： electronic interaction conductive catalysis subsurface transition metal

Steric hindrance modulation of hexaazatribenzanthraquinone isomers for high-capacity and wide-temperature-range aqueous proton battery

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National science Review 2024年第4期11卷 271-282页

作者： Mingsheng Yang Yuxin Hao Bei Wang Yan Wang Liping Zheng Rui Li Huige Ma Xinyu Wang Xiaoming Jing Hongwei Li Mengxiao Li Zhihui Wang Yujie Dai Guangcun Shan Mingjun Hu Jun Luo Jun Yang school of Materials science and engineering Beihang University Beijing Institute of Nanoenergy &Nanosystems Chinese Academy of Sciences Center on Nanoenergy Research School of Physical Science & TechnologyGuangxi University school of Chemistry and Chemical engineering Center on Nanoenergy Research Guangxi University school of Instrumentation science and Opto-electronics engineering Beihang University ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of China

Organic materials with rich active sites are good candidates of high-capacity anodes in aqueous batteries,but commonly low utilization of active sites limits their capacity.Herein,two isomers,symmetric and asymmetric hexaazatribenzanthraquinone（s-HATBAQ and a-HATBAQ）,with rich active sites have been synthesized in a controllable manner.It has been revealed for the first time that a sulfuric acid catalyst can facilitate the stereoselective formation of s-HATBAQ.Attributed to the reduced steric hindrance in favor of proton insertion as well as the amorphous structure conducive to electrochemical dynamics,s-HATBAQ exhibits 1.5 times larger specific capacity than a-HATBAQ.Consequently,the electrode of s-HATBAQ with50% reduced graphene oxide（s-HATBAQ-50%rGO） delivers a record high specific capacity of405 mAh g-1in H2SO4electrolyte.Moreover,the assembled MnO2//s-HATBAQ-50%rGO aqueous proton full batteries show an exceptional cycling stability at 25℃ and can maintain ～92% capacity after1000 cycles at 0.5 A g-1at-80℃.This work demonstrates the controllable synthesis of isomers,showcases a wide-temperature-range prototype proton battery and highlights the significance of precise mole cular structure modulation in organic energy storage.

关键词： stereoisomers steric effect aqueous battery super cycling stability ultra-low temperature proton battery

(Parallel) kinetic resolution of 3,3-disubstituted indolines via organocatalyzed reactions with azodicarboxylates

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science China Chemistry 2024年第3期67卷 973-980页

作者： Qianwen Jiang Dekun Zhang Mengyao Tang Hua Liu Xiaoyu Yang school of physical science and Technology ShanghaiTech UniversityShanghai 201210China

A novel kinetic resolution(KR) method has been developed for 3,3-disubstituted indolines, whose catalytic asymmetric synthesis remains a significant challenge in organic synthesis. The key to the success of this KR protocol lies in the utilization of chiral phosphoric acid-catalyzed triazane formation reaction with azodicarboxylates, which enables the enantioselective synthesis of various substituted indolines bearing C3-quaternary stereocenters with good to high enantioselectivities(with sfactors up to 70). Moreover, an intriguing parallel kinetic resolution(PKR) has been developed by combining triazane formation and dehydrogenation reactions using different azodicarboxylates. Experimental studies have provided insight into the mechanism of this PKR reaction, demonstrating stereoselectivity in both triazane formation and dehydrogenation steps, favoring the opposite enantiomers. The large-scale synthesis and diverse derivatizations of the products, particularly the imine groupcontaining 3H-indoles, demonstrate the value of these(P)KR methods.

关键词： asymmetric organocatalysis kinetic resolution 3 3-disubstituted indolines azodicarboxylate triazanes

High-sensitivity photonic crystal fiber sensor based on surface plasmon resonance

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Optoelectronics Letters 2024年第7期20卷 393-399页

作者： FENG Huanting GAO Jiachen MING Xianbing school of physical science and Technology Tiangong University

In this paper, we propose a photonic crystal fiber(PCF) sensor based on the surface plasmonic resonance(SPR) effect for simultaneous temperature and refractive index(RI) measurement. The coupling characteristics and sensing performance of the sensor are analyzed using the full vector finite element method(FEM). The sensor provides two channels for independent measurement of RI and temperature. When operating independently, channel I supports y-polarized light with a sensitivity of up to 7 000 nm/RIU for detecting RI, while channel II supports x-polarized light with a sensitivity of up to 16 nm/°C for detecting temperature. Additionally, we investigate the influence of gold layer thickness on the sensing performance to optimize the sensor.

关键词： A

MCWOA Scheduler:Modified Chimp-Whale Optimization Algorithm for Task Scheduling in Cloud Computing

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Computers, Materials & Continua 2024年第2期78卷 2593-2616页

作者： Chirag Chandrashekar Pradeep Krishnadoss Vijayakumar Kedalu Poornachary Balasundaram Ananthakrishnan school of Computer science and engineering Vellore Institute of TechnologyChennai600127India Center for Cyber physical Systems School of Computer Science and EngineeringVellore Institute of TechnologyChennai600127India

Cloud computing provides a diverse and adaptable resource pool over the internet,allowing users to tap into various resources as needed.It has been seen as a robust solution to relevant challenges.A significant delay can hamper the performance of IoT-enabled cloud platforms.However,efficient task scheduling can lower the cloud infrastructure’s energy consumption,thus maximizing the service provider’s revenue by decreasing user job processing times.The proposed Modified Chimp-Whale Optimization Algorithm called Modified Chimp-Whale Optimization Algorithm(MCWOA),combines elements of the Chimp Optimization Algorithm(COA)and the Whale Optimization Algorithm(WOA).To enhance MCWOA’s identification precision,the Sobol sequence is used in the population initialization phase,ensuring an even distribution of the population across the solution space.Moreover,the traditional MCWOA’s local search capabilities are augmented by incorporating the whale optimization algorithm’s bubble-net hunting and random search mechanisms into MCWOA’s position-updating process.This study demonstrates the effectiveness of the proposed approach using a two-story rigid frame and a simply supported beam model.Simulated outcomes reveal that the new method outperforms the original MCWOA,especially in multi-damage detection scenarios.MCWOA excels in avoiding false positives and enhancing computational speed,making it an optimal choice for structural damage detection.The efficiency of the proposed MCWOA is assessed against metrics such as energy usage,computational expense,task duration,and delay.The simulated data indicates that the new MCWOA outpaces other methods across all metrics.The study also references the Whale Optimization Algorithm(WOA),Chimp Algorithm(CA),Ant Lion Optimizer(ALO),Genetic Algorithm(GA)and Grey Wolf Optimizer(GWO).

关键词： Cloud computing scheduling chimp optimization algorithm whale optimization algorithm

MDCN:Modified Dense Convolution Network Based Disease Classification in Mango Leaves

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Computers, Materials & Continua 2024年第2期78卷 2511-2533页

作者： Chirag Chandrashekar K.P.Vijayakumar K.Pradeep A.Balasundaram school of Computer science and engineering Vellore Institute of Technology(VIT)ChennaiIndia Center for Cyber physical Systems School of Computer Science and EngineeringVellore Institute of Technology(VIT)ChennaiIndia

The most widely farmed fruit in the world is mango.Both the production and quality of the mangoes are hampered by many diseases.These diseases need to be effectively controlled and mitigated.Therefore,a quick and accurate diagnosis of the disorders is essential.Deep convolutional neural networks,renowned for their independence in feature extraction,have established their value in numerous detection and classification tasks.However,it requires large training datasets and several parameters that need careful adjustment.The proposed Modified Dense Convolutional Network(MDCN)provides a successful classification scheme for plant diseases affecting mango leaves.This model employs the strength of pre-trained networks and modifies them for the particular context of mango leaf diseases by incorporating transfer learning techniques.The data loader also builds mini-batches for training the models to reduce training time.Finally,optimization approaches help increase the overall model’s efficiency and lower computing *** employed on the MangoLeafBD Dataset consists of a total of 4,000 images.Following the experimental results,the proposed system is compared with existing techniques and it is clear that the proposed algorithm surpasses the existing algorithms by achieving high performance and overall throughput.

关键词： Leaf disease detection deep convolutional neural networks transfer learning optimization MangoLeafBD Dataset

Rapid chemical recycling of waste polyester plastics catalyzed by recyclable catalyst

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Green Chemical engineering 2024年第2期5卷 257-265页

作者： Yu-Ji Luo Jia-Yin Sun Zhi Li school of physical science and Technology ShanghaiTech UniversityShanghai201210China

Waste plastics are serious environmental threats due to their low degradability and low recycling rate.Rapid and efficient waste plastics recycling technologies are urgently demanded for a sustainable future.Herein,we report a rapid,closed-loop,and streamlined process to convert polyesters such as poly(ethylene terephthalate)(PET)back to its purified monomers.Using trifluoromethanesulfonic acid or metal triflates as the recyclable catalyst,polyesters such as PET can be completely depolymerized by simple carboxylic acids within 1 h.By coupling this acidolysis with a subsequent hydrogenolysis process,the consumed carboxylic acid was recovered and the closed-loop of PET depolymerization could be established.All catalysts and depolymerization agents are fully recycled while only PET and hydrogen are consumed.

关键词： Chemical recycling Waste polyester plastics Acidolysis Recyclable catalyst

Higher-dimensional Chen-Lee-Liu equation and asymmetric peakon soliton

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Chinese Physics B 2024年第4期33卷 224-229页

作者：韩巧红贾曼 school of physical science and Technology Ningbo UniversityNingbo 315211China

Integrable systems play a crucial role in physics and mathematics.In particular,the traditional(1+1)-dimensional and(2+1)-dimensional integrable systems have received significant attention due to the rarity of integrable systems in higher dimensions.Recent studies have shown that abundant higher-dimensional integrable systems can be constructed from(1+1)-dimensional integrable systems by using a deformation algorithm.Here we establish a new(2+1)-dimensional Chen-Lee-Liu(C-L-L)equation using the deformation algorithm from the(1+1)-dimensional C-L-L equation.The new system is integrable with its Lax pair obtained by applying the deformation algorithm to that of the(1+1)-dimension.It is challenging to obtain the exact solutions for the new integrable system because the new system combines both the original C-L-L equation and its reciprocal transformation.The traveling wave solutions are derived in implicit function expression,and some asymmetry peakon solutions are found.

关键词： higher dimensional Chen-Lee-Liu equation Lax integrable system deformation algorithm implicit traveling wave solutions