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Wideband chaos generation using a VCSEL with intensity modulation optical injection for random number generation

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Science China(Information Sciences) 2024年第6期67卷 457-458页

作者： Yu HUANG Shuangquan GU Yuhang FENG Yigong YANG Shuiying XIANG Pei ZHOU Nianqiang LI School of Optoelectronic Science and Engineering & Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University State key laboratory of Integrated Service Networks Xidian University key lab of Advanced Optical Manufacturing Technologies of Jiangsu Province & key lab of Modern Optical Technologies of Education Ministry of China Soochow University

Physical random numbers have been widely used in modern network society,such as the generation of cryptographic keys for classical and quantum cryptography systems[1].Among the many sources of physical entropy,chaotic semiconductor lasers have attracted wide attention due to their desired characteristics including larger bandwidth,low cost,and monolithic integration[2].

关键词： Optical signal processing

Cooperative User-Scheduling and Resource Allocation Optimization for Intelligent Reflecting Surface Enhanced LEO Satellite Communication

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China Communications 2024年第2期21卷 227-244页

作者： Meng Meng Bo Hu Shanzhi Chen Jianyin Zhang State key lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China State key lab of Wireless Mobile Communication China Academy of Telecommunication TechnologyBeijing 100191China Research Institute of China Mobile Beijing 100053China

Lower Earth Orbit(LEO) satellite becomes an important part of complementing terrestrial communication due to its lower orbital altitude and smaller propagation delay than Geostationary satellite. However, the LEO satellite communication system cannot meet the requirements of users when the satellite-terrestrial link is blocked by obstacles. To solve this problem, we introduce Intelligent reflect surface(IRS) for improving the achievable rate of terrestrial users in LEO satellite communication. We investigated joint IRS scheduling, user scheduling, power and bandwidth allocation(JIRPB) optimization algorithm for improving LEO satellite system *** optimization problem of joint user scheduling and resource allocation is formulated as a non-convex optimization problem. To cope with this problem, the nonconvex optimization problem is divided into resource allocation optimization sub-problem and scheduling optimization sub-problem firstly. Second, we optimize the resource allocation sub-problem via alternating direction multiplier method(ADMM) and scheduling sub-problem via Lagrangian dual method ***, we prove that the proposed resource allocation algorithm based ADMM approaches sublinear convergence theoretically. Finally, we demonstrate that the proposed JIRPB optimization algorithm improves the LEO satellite communication system throughput.

关键词： convex optimization intelligent reflecting surface LEO satellite communication OFDM

Adaptive strategies of high and low nucleic acid prokaryotes in response to declining resource availability and selective grazing by protozoa

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Science China Earth Sciences 2024年第6期67卷 1872-1884页

作者： Chen HU Liuqian YU Xiaowei CHEN Jihua LIU Yao ZHANG John BATT Xilin XIAO Qiang SHI Rui ZHANG Tingwei LUO Nianzhi JIAO Dapeng XU College of the Environment and Ecology Xiamen UniversityXiamen 361102China State key laboratory of marine Environmental Science College of Ocean and Earth SciencesFujian Key Laboratory of Marine Carbon SequestrationXiamen UniversityXiamen 361102China Joint lab for Ocean Research and Education(LORE)of Dalhousie University Canadaand Shandong University and Xiamen UniversityXiamen 361102China Earth Ocean and Atmospheric Sciences ThrustThe Hong Kong University of Science and Technology(Guangzhou)Guangzhou 510000China Institute of marine Science and Technology Shandong UniversityQingdao 266237China Department of Oceanography Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada Institute for Advanced Study Shenzhen UniversityShenzhen 518060China Carbon Neutral Innovation Research Center Xiamen UniversityXiamen 361102China

Prokaryotes play a fundamental role in global ocean biogeochemical ***,how the abundance and metabolic activity of ecologically distinct subgroups(i.e.,high nucleic acid(HNA)and low nucleic acid(LNA)cells),and their regulating factors,change in response to changing marine environmental conditions remains poorly ***,we delved into the time-evolving dynamic responses of the HNA and LNA prokaryotic subgroups to declining resource availability and selective grazing by protozoa by conducting a 73-day incubation experiment in a large-volume(117,000 L)macrocosm that facilitates community-level *** found that the metabolic activity of the HNA subgroup was higher than that of the LNA subgroup when the macrocosm was resource replete but that the HNA subgroup declined more rapidly than the LNA subgroup as the resources became increasingly scarce,leading to a steadily increasing contribution of LNA cells to prokaryotic ***,as resources in the macrocosm became limited,protozoan grazing preference shifted from the HNA to the LNA subgroup and the contributions of the LNA subgroup to the carbon flow within the macrocosm *** findings highlight the resilience of LNA cells in resource-limited environments,illuminate the critical role of selective grazing by protozoa in balancing distinct prokaryotic subgroups under changing resource conditions,and demonstrate the complex and adaptive interactions between protozoa and prokaryotes across diverse environmental contexts.

关键词： Microbial loop Macrocosm experiment Prokaryote Top-down and bottom-up controls Carbon flow

Evaluation of the Shallow Gas Hydrate Production Based on the Radial Drilling-Heat Injection-Back Fill Method

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Journal of Ocean University of China 2024年第1期23卷 119-128页

作者： CHEN Qiang WAN Yizhao WU Nengyou SUN Jianye WANG Jian LIU Changling LI Yanlong LI Chengfeng HU Gaowei key laboratory of Gas Hydrate Ministry of Natural ResourcesQingdao 266071China laboratory for marine Mineral Resources Laoshan LaboratoryQingdao 266071China CNPC Offshore Engineering Company Limited Beijing 100028China Technology Innovation Center for marine Methane Monitoring Ministry of Natural ResourcesQingdao 266071China

It has been evidenced that shallow gas hydrate resources are abundant in deep oceans *** geological back-ground,occurrence,and other characteristics differ significantly from deep-seated *** of the high risk of well construction and low production efficiency,they are difficult to be recovered by using conventional oil production *** a result,this paper proposes an alternative design based on a combination of radial drilling,heat injection,and backfilling ***-branch holes are used to penetrate shallow gas hydrate reservoirs to expand the depressurization area,and heat injection is utilized as a supplement to improve gas *** information collected from an investigation site close to the offshore production well in the South China Sea is used to assess the essential components of this plan,including well construction stability and gas production *** demonstrates that the hydraulic fracturing of the 60mbsf overburden layer can be prevented by regulating the drilling fluid ***,the traditional well structure is unstable,and the suction anchor is advised for better mechanical *** gas produc-tion rate can be significantly increased by combining hot water injection and depressurization ***,the suitable produc-tion equipment already in use is discussed.

关键词： shallow gas hydrate trail production radial drilling-heat injection-back fill method experimental and numerical simulation

experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

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Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： Xue-qin Ji Xiao-song Zhang Chen-jun Yang Xiao-qian Dong State key laboratory of Ocean Engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise *** blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance *** the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence *** measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip *** strong fluctuations of duct-surface pressures are caused by intensive tip separation *** duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces

New Benthic Fossils from the Late Ediacaran Strata of Southwestern China

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 311-323页

作者： LIU Junping LI Ming TANG Feng ZHAO Jiangtai SONG Sicun ZHOU Ying SONG Xiaohan REN Liudong School of Earth Science and Resources China University of GeosciencesBeijing 10083China Yunnan Institute of Geological Survey Kunming 650216China Chinese Academy of Geological Sciences Beijing 10037China key laboratory for Stratigraphy and Paleontology MNRCBeijing 10037China School of Earth Science and Engineering Nanjing UniversityNanjing 210093China Department of Earth Sciences University College LondonLondon WC1E 6BTU.K. CAS and Shandong Province key laboratory of experimental marine biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdaoShandong 266071China Institute of Geology Chinese Academy of Geological SciencesBeijing 10037China

The Jiangchuan Biota from the Jiucheng Member(Mb.)of the Dengying Formation(Fm.),discovered in Jiangchuan,eastern Yunnan,China,is marked by copious macrofossils at the apex of the Ediacaran *** fauna features benthic algae with varied holdfasts and other fossils of indeterminate taxonomic affinity and is compositionally unique compared to the Shibantan and Gaojiashan biotas of the Dengying *** the Miaohe and Wenghui biotas of the Doushantuo Fm.,elsewhere in *** novel benthic saccular macroalgal fossil,named here Houjiashania yuxiensis *** ***.,from the Jiangchuan Biota is based on fossils that are sausage-shaped,elongate,tubular,ranging from 0.3 to 4 cm in length,and up to 0.8 cm in *** terminus is blunt and rounded to an obtuse angle,the other is bent with a spread-out surface resembling a holdfast,suggesting a three-dimensional ***,stipe-shaped outgrowths,likely vestiges of sessile saccular life forms,are prevalent in macroalgal fossils of analogous size and shape,as well as present brown algae Scytosiphonaceae,such as Colpomenia and *** new findings augment the diversity of benthic algae,such as those known from the Early Neoproterozoic Longfengshan Biota in North *** benthic algal macrofossils in the Jiucheng *** to knowledge of Late Ediacaran metaphyte diversification and offer more clues about the evolutionary positioning of primitive *** co-occurrence of numerous planktonic and benthic multicellular algae and planktonic microbes might have facilitated ecologically the more extensive later Cambrian explosion evidenced by the Chengjiang Biota in Yunnan.

关键词： paleophytology benthic saccular algae algal evolution Neoproterozoic Jiucheng Member Jiangchuan Biota Yunnan Province

Reversing free-electron transfer of sulfide cocatalyst for exceptional photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第4期171卷 147-149页

作者： Yanfeng Zhang Zhenyi Zhang National experimental Chemistry Teaching Center Hebei Key Laboratory of Inorganic Nano-materialsCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China key laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S ***,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and *** anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.

关键词： Photocatalysis Cocatalyst Electron reversal Antibonding-orbital occupancy S–H bonds

Heterostructural NiFeW disulfide and hydroxide dual‐trimetallic core‐shell nanosheets for synergistically effective water oxidatio

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Carbon Energy 2024年第8期6卷 192-204页

作者： Peng‐Fei Guo Yang Yang Bing Zhu Qian‐Nan Yang Yan Jia Wei‐Tao Wang Zhao‐Tie Liu Shi‐Qiang Zhao Xun Cui key laboratory of Chemical Additives for China National Light Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and TechnologyXi'anChina School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi'anChina key laboratory of Carbon Materials of Zhejiang Province Wenzhou Key Lab of Advanced Energy Storage and ConversionZhejiang Province Key Lab of Leather EngineeringCollege of Chemistry and Materials EngineeringWenzhou UniversityWenzhouChina State key laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhanChina

A stable and highly active core‐shell heterostructure electrocatalyst is essential for catalyzing oxygen evolution reaction(OER).Here,a dual‐trimetallic core‐shell heterostructure OER electrocatalyst that consists of a NiFeWS_(2)inner core and an amorphous NiFeW(OH)_(z)outer shell is designed and synthesized using in situ electrochemical *** electrochemical measurements of different as‐synthesized catalysts with a similar mass loading suggest that the core‐shell Ni_(0.66)Fe_(0.17)W_(0.17)S_(2)@amorphous NiFeW(OH)_(z)nanosheets exhibit the highest overall performance compared with that of other bimetallic reference catalysts for the ***,the nanosheet arrays were in situ grown on hydrophilic‐treated carbon paper to fabricate an integrated three‐dimensional electrode that affords a current density of 10 mA cm^(−2)at a small overpotential of 182 mV and a low Tafel slope of 35 mV decade^(−1)in basic *** Faradaic efficiency of core‐shell Ni_(0.66)Fe_(0.17)W_(0.17)S_(2)@amorphous NiFeW(OH)_(z)is as high as 99.5%for *** scanning electron microscope,transmission electron microscope,and X‐ray photoelectron spectroscopy analyses confirm that this electrode has excellent stability in morphology and elementary composition after long‐term electrochemical ***,density functional theory calculations further indicate that the core‐shell heterojunction increased the conductivity of the catalyst,optimized the adsorption energy of the OER intermediates,and improved the OER *** study provides a universal strategy for designing more active core‐shell structure electrocatalysts based on the rule of coordinated regulation between electronic transport and active sites.

关键词： amorphous NiFeW hydroxide core‐shell heterojunction in situ electrochemical tuning NiFeW disulfide oxygen evolution reaction

Combining genome-wide association study and transcriptome analysis to identify molecular markers and genetic basis of population-asynchronous ovarian development in Coilia nasus

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Zoological Research 2024年第3期45卷 491-505页

作者： Yue Yu Shi-Ming Wan Cheng-You Huang Shuang-Meng Zhang Ai-Li Sun Jun-Qi Liu Shun-Yao Li Yong-Fu Zhu Shu-Xin Gu Ze-Xia Gao College of Fisheries Hubei Hongshan Laboratory/Key Lab of Freshwater Animal BreedingMinistry of Agriculture and Rural Affairs/Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic BeltMinistry of EducationHuazhong Agricultural UniversityWuhanHubei 430070China laboratory for marine biology and Biotechnology Qingdao Marine Science and Technology CenterQingdaoShandong 266237China Wuhan Hengyuxin Technology Breeding Professional Cooperative WuhanHubei 430117China Hubei Provincial Aquatic Science Research Institute WuhanHubei 430208China Zhenjiang Jiangzhiyuan Fishery Technology Co. Ltd.ZhenjiangJiangsu 212213China

Coilia nasus,a migratory fish species found in the middle and lower reaches of the Yangtze River and along offshore areas of China,possesses considerable aquacultural and economic ***,the species faces challenges due to significant variation in the gonadal development rate among females,resulting in inconsistent ovarian maturation times at the population level,an extended reproductive period,and limitations on fish growth rate due to ovarian *** the present study,we combined genome-wide association study(GWAS)and comparative transcriptome analysis to investigate the potential single nucleotide polymorphisms(SNPs)and candidate genes associated with population-asynchronous ovarian development in *** of the female population based on whole-genome resequencing yielded 2120695 high-quality SNPs,39 of which were suggestively associated with ovarian *** note,a significant SNP peak on LG21 containing 30 suggestively associated SNPs was identified,with cpne5a determined as the causal gene of the ***,single-marker and haplotype association analyses were performed on cpne5a,revealing four genetic markers(P0.9)significantly associated with the *** transcriptome analysis of precociously and normally maturing individuals screened out 29 and 426 overlapping differentially expressed genes in the brain and ovary,respectively,between individuals of different body *** the GWAS and transcriptome analysis results,this study identified genes and pathways related to hypothalamic-pituitary-gonadal axis hormone secretion,extracellular matrix,angiogenesis,and gap junctions involved in population-asynchronous ovarian *** insights gained from this study provide a basis for a deeper understanding of the molecular mechanisms underlying ovarian development in fish and may facilitate the genetic breeding of *** strains exhibiting population-synchronous ovarian

关键词： Coilia nasus GWAS Transcriptome Ovarian development SNP