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Chinese Geographical Science 2022年第1期32卷 49-63页

作者： MA Li KANG lei tian Huazheng XU Die Institute of Geographic Sciences and Nature Resources Research Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of SciencesBeijing 100101.China College of Resources ancl Environment University of Chinese Academy of SciencesBeijing 100049China

Although the development of energy and mineral resources strongly supports China’s rapid industrialization and urbanization,it has led to a series of ecological and environmental *** the spatial regulation considering the ecological and environmental protection on energy and mineral resource development areas is an important aspect of realizing China’s sustainable *** this study,we mapped,categorized,and analyzed the ecological cumulative effects of the Chinese 134 prefectural mining units based on the pressure-state-response model,which is demonstrated as impact of mining activities on ecological environment,ecological environmental fragility,and ecological *** investigation developed a stress zoning typology of the mining units based on scores of three dimensions of the ecological cumulative effects and classified 134 prefectural mining units into eight types of stress zones.A series of regulation and policy suggestions have been proposed to different types of zones from three aspects:space control,intensity control,and development mode *** application of this evaluation and spatial zoning system will contribute to the refined spatial management of China’s mining areas.

关键词： ecological cumulative effects quantitative evaluation pressure-state-response model zoning

Design of sextuple-mode triple-ring HTS UWB filter using two-round interpolation

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Chinese Physics B 2021年第5期30卷 701-707页

作者： ming-En tian Zhi-He Long You Lan lei-lei He tian-Liang Zhang School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China Department of Mechanical Engineering City University of Hong KongKowloonHong Kong SARChina

A single-stage ring resonator capable of introducing six modes within the ultra-wideband(UWB)passband is *** sextuple-mode resonator consists of three rings and three sets of stepped-impedance open *** on this sextuple-mode resonator,a UWB filter fed by the interdigital-coupling line(ICL)is *** we propose a two-round interpolation method to obtain the filter's initial *** designed filter is fabricated on a double-sided YBCO/MgO/YBCO high-temperature superconducting(HTS)thin film for *** experimental results show that this UWB filter produces eight resonances in the passband eventually,which effectively improves the in-band reflection and the band-edge ***,the upper stopband performance is enhanced due to the transmission zeros(TZs)generated by the stepped-impedance open stubs and the ICL *** measured good performance verifies the practicability of the two-round interpolation approach,which can also be extended to other odd-even-mode filter designs.

关键词： HTS filter ring resonator sextuple-mode two-round interpolation ultra-wideband(UWB)

Elevated CO_(2) increases shoot growth but not root growth and C:N:P stoichiometry of Suaeda aralocaspica plants

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Journal of Arid Land 2021年第11期13卷 1155-1162页

作者： WANG lei FAN Lianlian JIANG Li tian Changyan State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China

The purpose of the current study was to investigate the eco-physiological responses,in terms of growth and C:N:P stoichiometry of plants cultured from dimorphic seeds of a single-cell C4 annual Suaeda aralocaspica(Bunge)Freitag and Schütze under elevated CO_(2).A climatic chamber experiment was conducted to examine the effects of ambient(720μg/L)and CO_(2)-enriched(1440μg/L)treatments on these responses in *** at vegetative and reproductive stages in *** showed that elevated CO_(2) significantly increased shoot dry weight,but decreased N:P ratio at both growth *** grown from dimorphic seeds did not exhibit significant differences in growth and C:N:P stoichiometric *** transition from vegetation to reproductive stage significantly increased shoot:root ratio,N and P contents,but decreased C:N,C:P and N:P ratios,and did not affect shoot dry ***,our results indicate that the changes in N:P and C:N ratios between ambient and elevated CO_(2) are mainly caused by the decrease of N content under elevated CO_(2).These results provide an insight into nutritional metabolism of single-cell C4 plants under climate change.

关键词： biomass CO_(2)elevation C:N:P stoichiometry seed heteromorphism Suaeda aralocaspica

Tracy-Widom distribution, Airy2 process and its sample path properties

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Applied Mathematics(A Journal of Chinese Universities) 2021年第1期36卷 128-158页

作者： SU Zhong-gen lei Yu-huan SHEN tian School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China

Tracy-Widom distribution was rst discovered in the study of largest eigenvalues of high dimensional Gaussian unitary ensembles(GUE),and since then it has appeared in a number of apparently distinct research *** is believed that Tracy-Widom distribution have a universal feature like classic normal ***2 process is de ned through nite dimensional distributions with Tracy-Widom distribution as its marginal *** this introductory survey,we will briey review some basic notions,intuitive background and fundamental properties concerning Tracy-Widom distribution and Airy2 *** sake of reading,the paper starts with some simple and well-known facts about normal distributions,Gaussian processes and their sample path properties.

关键词： Airy2 process Dyson Brownian motion Tracy-Widom distribution sample path property.

Separation and determination of acetyl-glutamine enantiomers by HPLC–MS and its application in pharmacokinetic study

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Journal of Pharmaceutical Analysis 2017年第5期7卷 303-308页

作者： Xiaoxiao Zhang lei Gao Zunjian Zhang Yuan tian Key Laboratory of Drug Quality Control & Pharmacovigilance (China Pharmaceutical University) Ministry of Education State Key Laboratory of Natural Medicine China Pharmaceutical University

A high-performance liquid chromatography coupled with mass spectrometry(HPLC–MS) method was established for the separation and determination of acetyl-glutamine enantiomers(acetylL-glutamine and acetylD-glutamine) simultaneously. Baseline separation was achieved on Chiralpak AD-H column(250 mm ×4.6 mm, 5 μm). n-Hexane(containing 0.1% acetic acid) and ethanol(75:25, v/v) were used as mobile phase at a flow rate of 0.6 m L/min. The detection was operated in the negative ion mode with an ESI source. [M-H]-m/z187.0540 for enantiomers and [M-H]-m/z 179.0240 for aspirin(IS) were selected as detecting ions. The linear range of the calibration curve for each enantiomer was 0.05–40 μg/m L. The precision of this method at concentrations of 0.5–20 μg/m L was within 7.23%, and the accuracy was 99.81%–107.81%. The precision at LOQ(0.05 μg/m L) was between 16.28% and 17.56%, which was poor than that at QC levels. The average extraction recovery was higher than 85% for both enantiomers at QC levels. The pharmacokinetics of enantiomers was found to be stereoselective. There was not chiral inversion in vivo or in vitro between enantiomers.

关键词： HPLC–MS Acetyl-glutamine Enantiomers separation Pharmacokinetics Chiral inversion

Subspace-Based Blind Channel Estimation Method for MIMO-OFDM Systems

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Wuhan University Journal of Natural Sciences 2005年第2期10卷 413-416页

作者： HOUYong-min RONGMeng-tian DepartmentofElectronicEngineering ShanghaiJiaotongUniversityShanghai200030China

A subspace-based blind channel estination algo rithm for MIMO-OFDM systems is proposed. This algorithm exploits the cyclostationarity introduced by cyclic prefix of OFDM to estimate the channel parameters. The proposed new algorithm is found to be outperforming the other algorithm with respect to convergence rate and achievable mean square error and robustness to channel order over determination.

关键词： MIMO OFDM blind channel estimation subspace method

Associative Tasks Computing Offloading Scheme in Internet of Medical Things with Deep Reinforcement Learning

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China Communications 2024年第4期21卷 38-52页

作者： Jiang Fan Qin Junwei Liu lei tian Hui School of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

The Internet of Medical Things(Io MT) is regarded as a critical technology for intelligent healthcare in the foreseeable 6G era. Nevertheless, due to the limited computing power capability of edge devices and task-related coupling relationships, Io MT faces unprecedented challenges. Considering the associative connections among tasks, this paper proposes a computing offloading policy for multiple-user devices(UDs) considering device-to-device(D2D) communication and a multi-access edge computing(MEC)technique under the scenario of Io MT. Specifically,to minimize the total delay and energy consumption concerning the requirement of Io MT, we first analyze and model the detailed local execution, MEC execution, D2D execution, and associated tasks offloading exchange model. Consequently, the associated tasks’ offloading scheme of multi-UDs is formulated as a mixed-integer nonconvex optimization problem. Considering the advantages of deep reinforcement learning(DRL) in processing tasks related to coupling relationships, a Double DQN based associative tasks computing offloading(DDATO) algorithm is then proposed to obtain the optimal solution, which can make the best offloading decision under the condition that tasks of UDs are associative. Furthermore, to reduce the complexity of the DDATO algorithm, the cacheaided procedure is intentionally introduced before the data training process. This avoids redundant offloading and computing procedures concerning tasks that previously have already been cached by other UDs. In addition, we use a dynamic ε-greedy strategy in the action selection section of the algorithm, thus preventing the algorithm from falling into a locally optimal solution. Simulation results demonstrate that compared with other existing methods for associative task models concerning different structures in the Io MT network, the proposed algorithm can lower the total cost more effectively and efficiently while also providing a tradeoff between delay and energy co

关键词： associative tasks cache-aided procedure double deep Q-network Internet of Medical Things(IoMT) multi-access edge computing(MEC)

A zebrafish gene trap line expresses GFP recapturing expression pattern of foxj1b

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Journal of Genetics and Genomics 2009年第10期36卷 581-589页

作者： tian tian Long Zhao Xinyi Zhao min Zhang Anming Meng Protein Science Laboratory of ministry of Education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China State Key Laboratory of Biomembrane and Membrane Engineering Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Foxj1 has been found to play an important role in cilia formation and function in vertebrates. The zebrafish or Xenopus genome expresses two Foxjl genes, foxjlalFoxJ1 and foxjlb/FoxJ1.2. In this study, we have generated a zebrafish transgenic line T2BGSZIO by Tol2 transposon-based gene trapping approach. T2BGSZ10 transgenic fish carry an insertion of the transposon genome into the first intron of thefoxj1b locus. This insertion results in GFP expression in the forebrain, otic vesicles, floorplate, pronephric ducts and other domains during embryogenesis, which recaptures the expression pattern offoxj1b. Although normal expression offoxj1b is dramatically reduced, T2BGSZ10 homozygous embryos develop normally and grow to adulthood without detectable defects, which may be due to the incomplete interruption of foxjlb expression. Nevertheless, this transgenic line may serve as a useful model for dynamic observation of GFP-labeled tissues and organs and for isolation of GFP-labeled cells.

关键词： zebrafish transposon embryo transgenic foxj1

Quaternary Intrusions from the Zhongjiannan Basin,South China Sea:Their Relationship with the Hainan Mantle Plume and Influence on Hydrocarbon Reservoirs

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Acta Geologica Sinica(English Edition) 2023年第1期97卷 376-392页

作者： HE Yanxin LIU Jianping WANG lei tian Wei Key Laboratory of Orogenic Belts and Crustal Evolution MOESchool of Earth and Space SciencesPeking UniversityBeijing 100871China School of Petroleum Engineering Chongqing University of Science and TechnologyChongqing 401331China Guangzhou Marine Geological Survey Ministry of Natural ResourcesGuangzhou 510760China School of Marine Sciences Sun Yat-sen UniversityZhuhai 519000China

The transportation of magma in sedimentary basins often occurs through extensive dyke-sill *** role of sills on the plumbing system in rifted margins and the impact of sills on hydrocarbon reservoirs of prospective sedimentary basins has long been an area of great industrial interest and scientific *** on 2D seismic reflection,we present data on how the sills emplaced to form a magmatic plumbing system of the volcanic system for the Zhongjiannan Basin(ZJNB).The results show that sixty-nine sills and fourteen forced folds have been *** distribution and geometry of the sills suggest that magma flowed from west to east and then ascended to near the *** onlap relationship of the forced folds indicates that the timing of magmatic activities can be constrained at ca.0.2 *** spatial and temporal occurrences of intrusions imply that the strong post-rift magmatism in ZJNB was associated with the Hainan mantle plume arising from the core-mantle ***,these forced folds could produce several types of hydrocarbon traps,due to accommodation through bending and uplift of the overlying rock and free surface,but it is critical to evaluate the effect of such emplacement when setting exploration targets.

关键词： sill intrusions forced fold petroleum traps Hainan mantle plume Zhongjiannan basin

Polycyclic aromatic hydrocarbons in the centralized wastewater treatment plant of a chemical industry zone:Removal,mass balance and source analysis

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Science China Chemistry 2012年第3期55卷 416-425页

作者： YAO min ZHANG XingWang lei LeCheng Industrial Ecology and Environment Research Institute Department of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China

Increased attention has been given to the fate of pollutants such as polycyclic aromatic hydrocarbons (PAHs) introduced to the wastewater treatment *** and adsorbed PAHs were detected in the centralized wastewater treatment plant of a chemical industry zone in Zhejiang Province,*** most abundant PAHs were the low molecular weight PAHs (e.g.,Acy,Ace,Flu and Phe),accounting for more than 80% of the total 16 PAHs in each treatment *** partitioning suggested that the removal of PAHs in every treatment stage was influenced greater by the sorption of particles or *** removal efficiencies of individual PAHs ranged between 4% and 87% in the primary sedimentation stage,between 1% and 42% in anaerobic hydrolysis stage,between <1% and 70% in aerobic bio-process stage,between 1.5% and 80% in high-density clarifier stage,and between 44% and 97% in the whole treatment *** balance calculations in primary stage showed significant losses for low molecular weight PAHs and relatively good agreements for high molecular weight PAHs as well as in anaerobic hydrolysis,high-density clarifier stage and sludge stream for most *** gains of 60%-150% were obtained for high molecular weight PAHs in aerobic bio-process stage due to biosorption and *** investigations found that PAHs entering the wastewater treatment plant (WWTP) could be derived from the dyeing chemical processes as the byproducts,and the contribution supported by the largest dyeing chemical group was up to 48%.

关键词： polycyclic aromatic hydrocarbons removal efficiency mass balance source analysis centralized wastewater treatment plant