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Science China Earth Sciences 2022年第12期65卷 2219-2236页

作者： chen he Ding he Chunmao chen Quan SHI State Key Laboratory of heavy Oil Processing China University of PetroleumBeijing 102249China Department of Ocean Science and Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) The Hong Kong University of Science and TechnologyHong Kong 999077China

Dissolved organic matter(DOM)plays an important role in the global carbon cycle,and an in-depth analysis of its chemical composition is fundamental to the study of its environmental and biogeochemical behavior and *** is a complex mixture of organic substances,and determining its molecular composition is a long-standing challenge in the field of analytical *** development and application of Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)has enabled the identification of the chemical composition of DOM at the molecular *** paper summarizes progress made in the molecular characterization of DOM based on the FT-ICR MS technique,including DOM sample pretreatment methods,mass spectrometry ionization techniques,data acquisition,data processing and presentation,and molecular structure *** on the work done by the instrument at the State Key Laboratory of heavy Oil Processing in the China University of Petroleum,Beijing,we introduce applications of FT-ICR MS in the fields of earth science,environmental science and engineering,and look ahead to further research directions in the future.

关键词： Dissolved organic matter FT-ICR MS Molecular composition Recalcitrant dissolved organic matter High resolution mass spectrometry

A 3-D Multiuser HAP-MIMO Channel Model Based on Dynamic Evolution of LOS Components

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Chinese Journal of Electronics 2019年第3期28卷 645-650页

作者： LIAN Zhuxian JIANG Lingge he chen he Di Department of Electronic Engineering Shanghai Jiaotong University National Mobile Communications Research Laboratory Southeast University

A theoretical Three dimensional(3-D) multiuser High altitude platform(HAP) Multipleinput multiple-output(MIMO) channel model based on dynamic evolution of the Line-of-sight(LOS) components is proposed. In this paper, we consider that the LOS components could re-appear after they have vanished,and a two-state Continuous-time Markov chain(CTMC)is used to model the dynamic evolution of the LOS components. The survival probabilities of the LOS components are derived by using Chapman-Kolmogorov(C-K) equations, and the closed-form expressions are derived in this paper. Using the survival probabilities, the spatial correlation functions are derived. Measurements show that a two-state CTMC is indispensable to investigate the dynamic properties of the LOS components.

关键词： High altitude platform(HAP) Twostate Continuous-time Markov chain(CTMC) ChapmanKolmogorov(C-K) equations

New Name for Aulacus erythrogaster he and chen(Hymenoptera:Evanioidea,Aulacidae)

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Entomotaxonomia 2007年第1期29卷 66-66页

作者：何俊华陈学新浙江大学农业与生物技术学院昆虫科学研究所浙江杭州310029

Because Aulacus erythrogaster he et chen 2002 is preoccupied by Aulacus erythrogaster Kieffer 1904, authors propose a new name Aulacus sinensis he and chen as replacement name for A. erythrogaster he et chen.

关键词： Hymenopter Evanioidea Aulacidae Aulacus replacement name

Degradation of multiphoton signal and resolution when focusing through a planar interface with index mismatch:Analytical approximation and numerical investigation

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Journal of Innovative Optical health Sciences 2018年第4期11卷 72-80页

作者： Ping Qiu chen he College of Physics and Energy Shenzhen University ShenzhenGuangdong 518060P.R.China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Optoelectronic Engineering Shenzhen University ShenzhenGuangdong 518060P.R.China

Multiphoton microscopy(MPM)is an invaluable tool for visualizing subelllar structures in biomedical and life ***-numerical-aperture(NA)immersion objective lenses are used to deliver excitation light to focus inside the biological *** refractive index of tissue is commonly different from that of the immersion medium,which introduces spherical aberration,leading to signal and resolution degradation as imaging depth ***,the explicit dependence of this index mismatch induced aberration on the involved physical parameters is not dlear,espeially its dependence on index ***,from the vectorial equations for fo-cusing through a planar interface bet ween materials of mismatched refractive indices,we derive an approximate analytical expression for the spherical *** analytical expression explicitly reveals the dependence of spherical aberration on index mismatch,imaging depth and excitation wavelength,from which we can expect the following qualitative behaviors:(1)Mul-tiphoton sigmal and resolution degradation is less for longer excitation wavelength,(2)a longer wavelength tolerates a higher index mismatch,(3)a longer wavelength tolerates a larger imaging depth and(4)both signal and resohution degradations show the same dependence om imaging depth,regardless of NA or immersion on the condition that the integration angle is the *** numerical simulation results agree quite well with the above expectations based on the analytical *** theoretical results suggest the use of long excitation wavelength to better suppress index *** sigmal and resolution degradation in deep-tssue MPM.

关键词： Biomedical optical imaging nonlinear optics optical microscopy

Fixed Point Theorems for φ-Probabilistic Contraction in Hausdorff Fuzzy Metric Spaces

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Wuhan University Journal of Natural Sciences 2021年第3期26卷 243-248页

作者： chen he School of Mathematics and Statistics Wuhan UniversityWuhan 430072HubeiChina

In this paper,we discuss the common fixed point with respect to several self-mappings on fuzzy metric *** many authors put forward some relevant common fixed point theorems,and their theorems require that these mappings have some assumptions such as commutativity or ***,our results do not need these assumptions but only these mappings areφ-probabilistic *** defining a new mapping on the space which formed by compact sets,we can obtain these mappings’common fixed ***,we give some examples to justify our results.

关键词： fuzzy metric space φ-probabilistic contraction Hausdorff fuzzy metric common fixed point

Molecular transformation of dissolved organic matter in refinery wastewaters: Characterized by FT-ICR MS coupled with electrospray ionization and atmospheric pressure photoionization

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Petroleum Science 2023年第1期20卷 590-599页

作者： chen he Wei-Ming chen Chun-Mao chen Quan Shi State Key Laboratory of heavy Oil Processing Beijing Key Laboratory of Oil and Gas Pollution ControlChina University of PetroleumBeijing 102249China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduSichuan 611756China

Dissolved organic matter(DOM)in refinery wastewater is an extremely complex mixture of various organic *** mass spectrometry,it is impossible to characterize all of the DOM molecules with only one ionization *** this study,negative-ion,electrospray ionization(ESI),positive-ion ESI,and positive-ion atmospheric pressure photoionization(APPI)were coupled with Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)to analyze the molecular composition of DOM in a refinery wastewater stream during the treatment *** were obvious differences in the heteroatom composition,number of DOM constituents,and chemical properties in refinery wastewater under the three ionization *** CHO and CHOS compounds detected by(+)ESI,basic CHN and CHON compounds detected by(þ)ESI,and hydrocarbons detected by(+)APPI were analyzed to determine the molecular transformations that occurred during *** an anaerobic biological treatment process,acidic CHO and CHOS compounds with a high oxygen content were preferentially removed,and acidic CHO and CHOS compounds with a low oxygen content were *** an aerobic biological process,acidic CHO and CHOS compounds with a low oxygen content were preferentially removed,and acidic CHO and CHOS compounds with a high oxygen content were *** whole biological treatment process has a poor removal efficiency for CHN and CHON compounds,and *** activated carbon(AC)adsorption process removed different heteroatom compounds mainly with a low oxygen content for acidic and basic *** transformation mechanism of CHO and CHOS compounds in the biological treatment process was analyzed by the Kendrick mass defect(KMD)theory and a mass difference network *** the anaerobic process,large amounts of oxygenated CHO and CHOS compounds were degraded by decarboxylation,deoxydation,demethoxylation,and dehydration reactions,and converted to lower oxygen content *** the aerobic

关键词： Refinery wastewater DOM Molecular transformation ESI APPI FT-ICR MS

Modular Precoding Based on Zero Forcing in Large Scale Antenna Systems with Imperfect Channel State Information

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Chinese Journal of Electronics 2017年第2期26卷 424-429页

作者： XI Qi he chen JIANG Lingge Department of Electronic Engineering Shanghai Jiaotong University National Mobile Communications Research Laboratory Southeast University

In Large scale antenna systems(LSAS),the user number is usually much less than the number of base station *** leveraging this characteristic,Modular precoding based on zero forcing(MZF) is proposed to achieve higher spectrum efficiency than Maximum ratio combining(MRC),while preserve the advantage of distributive *** achievable rates of the MZF,MRC and Zero forcing(ZF) are derived under the generalized model of imperfect Channel state information(CSI).The imperfect CSI model includes the channel estimation delay,the noise in the pilot channel,and the pilot *** analytical achievable rates match the simulations even with a small number of base station *** the antenna number approaches to infinity,the analytical achievable rates of MZF converge to the analytical achievable rates of ZF.

关键词： Modular precoding based on zero forcing Capacity analysis Imperfect CSI Large scale antenna systems

Dynamic Decode-and-Forward Relaying with Partial CSIT and Optimal Time Allocation

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Chinese Journal of Electronics 2015年第1期24卷 193-198页

作者： SU Yinjie JIANG Lingge he chen Department of Electronic Engineering Shanghai Jiaotong University Department of Electronic Engineering Jiangsu University of Science and Technology

A Dynamic decode-and-forward(DDF)relaying protocol with partial Channel state information at the transmitter(CSIT) for a three-node half-duplex single-antenna network, which consists of a single sourcedestination pair and a relay, is proposed. A Diversity multiplexing tradeoff(DMT) analysis is presented, in which the DMT of the proposed protocol is derived in a closedform and an adaptive time allocation strategy is also developed to achieve the optimal performance. It is shown that time allocation with partial CSIT significantly improves the achievable DMT for DDF relaying. Moreover, unlike the existing DDF protocol with CSIT, which is performed with the assumption of long-term power constraint, the proposed protocol can be generalized to the practical scenarios where a strict short-term power constraint is often imposed on, due to the environmental safety and interference prevention.

关键词： Dynamic decode-and-forward(DDF) Diversity multiplexing tradeoff(DMT) Adaptive time allocation.

Cooperative spectrum sensing based on stochastic resonance in cognitive radio networks

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Science China(Information Sciences) 2014年第2期57卷 58-67页

作者： LIN YingPei he chen JIANG LingGe he Di Department of Electronic Engineering Shanghai Jiao Tong University

A new censoring cooperative spectrum sensing scheme based on stochastic resonance(SR)technique in cognitive radio(CR)network is proposed in this *** observations of the cooperative secondary users(SUs)whose statistics fall into the censoring interval are processed by SR system in the proposed *** hard fusion and the soft fusion for the censoring cooperative spectrum sensing scheme are analyzed *** analyses and simulation results show that the proposed censoring cooperative spectrum sensing scheme has the same detection performance as and lower computational complexity than the method that each cooperative SU performs spectrum sensing using SR-based energy detection,and its detection performance is superior to that of the conventional method that all the cooperative SUs perform spectrum sensing using energy detection in hard *** soft fusion,the proposed censoring cooperative spectrum sensing based on equal gain combination can achieve the optimal sensing performance approximately.

关键词： cognitive radio cooperative spectrum sensing stochastic resonance information fusion

A novel word length optimization method for radix-2k fixed-point FFT

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Science China(Information Sciences) 2018年第2期61卷 278-282页

作者： chen YANG Yizhuang XIE he chen Beijing Key Laboratory of Embedded Real-time Information Processing Technology Beijing Institute of Technology

Dear editor,Fast Fourier transform(FFT)is one of the most fundamental algorithms used in digital signal *** applications such as orthogonal frequency division multiplexing(OFDM),long term

关键词： A novel word length optimization method for radix-2~k fixed-point FFT length