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Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 43-50页

作者： Xiao-Bin liang bo li Shao-Ming Fei School of Mathematics and Computer Science Shangrao Normal UniversityShangrao 334001China Quantum Information Research Center Shangrao Normal UniversityShangrao 334001China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical ***,we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement *** any quantum state,we establish optimal sets of three observables for both product and summation forms of uncertainty relations,and analytically derive the corresponding tightest uncertainty *** demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation ***,the existence of the tightest constants excludes the validity of standard real quantum mechanics,underscoring the essential role of complex numbers in this ***,our findings resolve the conjecture posed in[***.118,180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties.

关键词： uncertainty relation the tightest uncertainty constants optimal observable sets

(+)/(-)-Mycosphatide A,a pair of highly oxidized polyketides with lipid-lowering activity from the mangrove endophytic fungus Mycosphaerella ***-DZG01

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Chinese Chemical Letters 2024年第9期35卷 210-213页

作者： Qi Tan run-Zhu Fan Wencong Yang Ge Zou Tao Chen Jianying Wu bo Wang Sheng Yin Zhigang She School of Chemistry Sun Yat-sen UniversityGuangzhou 510006China School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006China

(±)-Mycosphatide A(1a/1b),a pair of highly oxidized enantiomeric polyketides featuring a unique5/5/6/5-fused tetracyclic ring system,were isolated from the mangrove endophytic fungus Mycosphaerella *** structures were established by extensive spectroscopic analyses,single crystal Xray diffraction,and experimental electronic circular dichroism(ECD)spectra *** plausible biosynthetic pathway of 1 was proposed,which involved the generation of a key spiro[4.5]decane ***(+)-1a and(-)-1b exhibited significant lipid-lowering activity in 3T3-L1 adipocytes model,with EC50values of 7.85±1.56 and 8.87±0.80μmol/L,respectively.

关键词： Mangrove endophytic fungus Mycosphaerella sp. Polyketide Highly oxidized lipid-lowering activity

Microplastics in sediment of the Three Gorges Reservoir:abundance and characteristics under different environmental conditions

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Journal of Oceanology and limnology 2024年第1期42卷 101-112页

作者： Wang li bo ZU Yiwei liU Juncheng GUO Jiawen li College of River and Ocean Engineering Chongqing Jiaotong UniversityChongqing 400074China Chongqing Research Academy of Ecology and Environmental Sciences Chongqing 401147China

Freshwater microplastic pollution is an urgent issue of global concern,and research on the distribution in reservoirs is *** investigated the microplastic pollution levels in wet sediments collected from the Three Gorges Reservoir,the largest reservoir of *** show that microplastics were ubiquitous in the sediments of the Three Gorges Reservoir,and their abundance ranged from 59 to 276 pp/kg(plastic particles per kg,dry weight).Economic development and total population were important factors affecting the spatial heterogeneity of microplastic abundance,and the contribution of large cities along the reservoir to microplastic pollution should be paid with more *** microplastics were the most abundant type of microplastic particles in reservoir sediments,whereas polystyrene,polypropylene,and polyamide were the main types of *** apparent spatial heterogeneity in morphology and color of microplastics is attributed to different anthropogenic or landbased pollution ***,the accumulation of microplastics near the inlet of tributaries reflects the role of potential contributors of *** importantly,multiple bisphenols(BPs)and heavy metals detected at the microplastic surfaces indicate that microplastics can act as carriers of these pollutants in the environment in the same way as sediments did,which may alter the environmental fate and toxicity of these ***,we conclude that the Three Gorges Reservoir had been contaminated with microplastics,which posed a stress risk for organisms who ingest them along with their associated pollutants(BPs,heavy metals).

关键词： microplastics Three Gorges Reservoir sediment bisphenol heavy metal

A Multi-Token Sector Antenna Neighbor Discovery Protocol for Directional Ad Hoc Networks

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China Communications 2024年第7期21卷 149-168页

作者： Zhang Hang li bo Yan Zhongjiang Yang Mao li Xinru School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China The 54th Research Institute of CETC Shijiazhuang 050081China

In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc *** central concept of our work involves maintaining multiple tokens across the *** prevent mutual interference among multi-token holders,we introduce the time and space non-interference ***,we propose a master-slave strategy between *** the master token holder(MTH)performs the neighbor discovery,it decides which 1-hop neighbor is the next MTH and which 2-hop neighbors can be the new slave token holders(STHs).Using this approach,the MTH and multiple STHs can simultaneously discover their neighbors without causing interference with each *** on this foundation,we provide a comprehensive procedure for the M-SAND *** also conduct theoretical analyses on the maximum number of STHs and the lower bound of multi-token generation ***,simulation results demonstrate the time efficiency of the M-SAND *** compared to the QSAND protocol,which uses only one token,the total neighbor discovery time is reduced by 28% when 6beams and 112 nodes are employed.

关键词： multi-token neighbor discovery SAND protocol sector antenna ad hoc network

Rapid Simultaneous Determination of Four Ganoderic Acids in Ganoderma(Chinese Name:lingzhi)by Direct Infusion-Multiple Reaction Monitoring Cubed

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Journal of Analysis and Testing 2024年第1期8卷 52-62页

作者： Nian Wu bo Peng Ting li Pengfei Tu Shengpeng Wang bo li Wenjing liu Yuelin Song Modern Research Center for Traditional Chinese Medicine Beijing Research Institute of Chinese MedicineBeijing University of Chinese MedicineBeijing 100029China Amway(China)botanical Research Center Wuxi 214011China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipa 999078China Amway(Shanghai)Innovation&Science Co. LtdShanghai 201508China School of Pharmacy Henan University of Chinese MedicineZhengzhou 450046China

Attributing to the rapid demand expansion for the edible medicinal materials in the market,the limited throughput of highperformance liquid chromatography-multiple reaction monitoring(HPLC-MRM)cannot fully address the measurement workload for a huge number of testing ***,it is urgent to pursue more efficient approaches for the quality *** of the greater selectivity of MRM cubed(MRM^(3))over MRM,there might be a chance to omit the time-intensive LC *** current study,we attempted to develop a direct infusion(DI)-MRM^(3) program,and the applicability was thereafter assessed through simultaneous determination of four ganoderic acids(GAs)in one of the most famous tonic herbal medicines namely Ganoderma(Chinese name:lingzhi).Primary parameters such as Q1>Q3>QliT ion transitions,collision energy(CE),and excitation energy were optimized by programming online energy-resolved mass spectrometry with authentic compounds.A single DI-MRM measurement merely costed four minutes,and in spite of the wide occurrences of isomers,satisfactory selectivity was *** validation assays demonstrated the method to be sensitive,precise,accurate,and *** quantitative results from DI-MRM^(3) were also justified by conducting LC-MRM measurements in *** differences occurred for the content patterns between the two original sources namely Ganoderma lucidum and ***,and,moreover,either cultivar or harvest time showed dramatical influence on the quantitative features of the four targeted *** importantly,DI-MRM3 is a meaningful analytical option for rapid quantitative analysis of herbal medicines,because of the comparable reliability,nonetheless,less consumptions of both measurement time and solvent,compared with LC-MRM.

关键词： Direct infusion Multiple reaction monitoring cubed High-throughput quantitative analysis Ganoderic acids Ganoderma

Consistency of Tropospheric Water Vapor between Reanalyses and Himawari-8/AHI Measurements over East Asia

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Advances in Atmospheric Sciences 2024年第1期41卷 19-38页

作者： Di DI Jun li Yunheng XUE Min MIN bo li Zhenglong li Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Key Laboratory for Aerosol-Cloud-Precipitation China Meteorological AdministrationSchool of Atmospheric PhysicsNanjing University of Information Science and TechnologyNanjing 210044China FYSIC National Satellite Meteorological CenterChina Meteorological AdministrationBeijing 100081China Chengdu University of Information Science and Technology Chengdu 610225China School of Atmospheric Sciences and Guangdong Province Key laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen University and Southern Laboratory of Ocean Science and EngineeringZhuhai 519082China Cooperative Institute for Meteorological Satellite Studies University of Wisconsin–MadisonMadison WI 53706WisconsinUSA Wuxi University Wuxi 214105China

High spatiotemporal resolution radiances from the advanced imagers onboard the new generation of geostationary weather satellites provide a unique opportunity to evaluate the abilities of various reanalysis datasets to depict multilayer tropospheric water vapor(WV),thereby enhancing our understanding of the deficiencies of WV in reanalysis *** on daily measurements from the Advanced Himawari Imager(AHI)onboard the Himawari-8 satellite in 2016,the bias features of multilayer WV from six reanalysis datasets over East Asia are thoroughly *** assessments show that wet biases exist in the upper troposphere in all six reanalysis datasets;in particular,these biases are much larger in ***,we find better depictions of WV in the middle troposphere than in the upper *** accuracy of WV in the ERA5 dataset is the highest,in terms of the bias magnitude,dispersion,and pattern *** characteristics of the WV bias over the Tibetan Plateau are significantly different from those over other parts of East *** addition,the reanalysis datasets all capture the shift of the subtropical high very well,with ERA5 performing better overall.

关键词： AHI reanalysis dataset multilayer water vapor assessment radiative transfer model

A Fast Startup Crystal Oscillator with Digital SAR-AFC Based Two-Step Injection

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Chinese Journal of Electronics 2024年第5期33卷 1147-1153页

作者： bo ZHOU Yifan li Zuhang WANG School of Integrated Circuits and Electronics Beijing Institute of Technology

Crystal oscillators（XOs） provide a high-precision reference frequency but have a long startup time,which severely increases the average power consumption in duty-cycled *** paper proposes a fully-digital low-cost two-step injection technique,by using a successive approximation register（SAR） based auto frequency control（AFC） loop,to speed up the startup behavior of XOs.A theoretical analysis is carried out to determine the optimum injection time and design low-power *** in a 65 nm CMOS process,the proposed 12 MHz fast startup XO occupies an active area of 0.02 mm2and achieves a startup time less than 35 μ*** XO power consumption in the steady state is 40 μW from a 1.0-V supply,with a startup energy of 17.2 nJ.

关键词： Time-frequency analysis Power demand Power measurement Crystals Time measurement Steady-state Registers Crystal oscillator Two-step injection Successive approximation register Auto frequency control Fully-digital Fast startup ENERGY

Core-shell heterostructure engineering of CoP nanowires coupled NiFe LDH nanosheets for highly efficient water/seawater oxidation

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Chinese Chemical Letters 2024年第8期35卷 549-553页

作者： Guo-Hong Gao run-Ze Zhao Ya-Jun Wang Xiao Ma Yan li Jian Zhang Ji-Sen li School of Chemistry Chemical Engineering and MaterialsJining UniversityQufu 273155China Institute of Physical Education Jining UniversityQufu 273155China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

Searching for efficient nonprecious metal-based catalysts toward oxygen evolution reaction(OER)are of significance for seawater ***,a core-shell-structured hybrid of cobalt phosphide nanowires@NiFe layered double hydroxide nanosheets grown on conductive nickel foam(CoP@NiFe LDH/NF)is prepared by a feasible approach at low *** charming structure can provide numerous phosphide/hydroxide heterogenous interfaces,expose abundant active sites,and boost elec-tron/mass transfer,synergistically enhancing catalytic OER *** employed as an electrocatalyst toward the OER,the resultant CoP@NiFe LDH/NF only requires a small overpotential of 287 mV to pro-vide 300 mA/cm^(2)current density as well as long-time durability in 1.0 mol/L KOH *** regula-tion of electronic states and surface reconstruction synergistically contribute to highly efficient seawater *** work provides an opportunity to construct efficient and inexpensive electrocatalysts for hydrogen production.

关键词： Cobalt phosphide NiFe layered double hydroxide Interfacial engineering Oxygen evolution reaction Seawater oxidation

Strong and tough chitin hydrogel constructed by dehydration and rehydration strategy

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Nano Research 2024年第9期17卷 8192-8199页

作者： Rui-Rui liu li-bo Mao Shu-Hong Yu Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials and ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

As a renewable,biocompatible,biodegradable soft material,chitin hydrogels have better advantages in stability,antibacterial activity,antifouling,cost,immunogenicity,and so on than most polymer ***,compared with other widely used polymer hydrogels with high strength and toughness,the practical applications of chitin-based hydrogels have been limited by their weak mechanical properties,such as cartilage repair and meniscus ***,we present the design and fabrication of chitin hydrogels with excellent mechanical strength and toughness by a dehydration and rehydration *** sequential dehydration and rehydration processes,the crystalline domains in the chitin hydrogels can be properly *** optimized crystallinity,the elastic modulus of the chitin hydrogels exceeds all previously reported values,and the fracture toughness is even comparable to some synthetic polymer hydrogels,while maintaining a high-water-content of about 80 wt.%.At the same water content,the mechanical properties of the chitin hydrogels are positively correlated with the hydrogel crystallinity,which proves that the change of mechanical properties of hydrogels is not simply dependent on weight *** hydrogels can be further strengthened by incorporating other biopolymers that are intrinsically weak,which makes the hydrogels promising for applications in fields such as cartilage repair and meniscus ***,the hydrogels enable loading and release of water-soluble and poorly water-soluble *** highly extendable strengthening and toughening strategy of chitin and chitin-based biopolymer hydrogels paves the way for their widely applications.

关键词： chitin hydrogel crystallinity rehydration chemical transformation strong and tough