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Soil Respiration of Biologically-Crusted Soils in Response to Simulated Precipitation Pulses in the Tengger Desert, Northern China

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Pedosphere 2018年第1期28卷 103-113页

作者： LI Xiaojun ZHAO yang yang haotian ZHANG Peng GAO Yongping Shapotou Desert Research and Experiment Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Soil respiration(SR) is a major process of carbon loss from dryland soils, and it is closely linked to precipitation which often occurs as a discrete episodic event. However, knowledge on the dynamic patterns of SR of biologically-crusted soils in response to precipitation pulses remains limited. In this study, we investigated CO_2 emissions from a moss-crusted soil(MCS) and a cyanobacterialichen-crusted soil(CLCS) after 2, 4, 8, 16, and 32 mm precipitation during the dry season in the Tengger Desert, northern *** showed that 2 h after precipitation, the SR rates of both MCS and CLCS increased up to 18-fold compared with those before rewetting, and then gradually declined to background levels; the decrease was faster at lower precipitation amount and slower at higher precipitation amount. The peak and average SR rates over the first 2 h in MCS increased with increasing precipitation amount, but did not vary in CLCS. Total CO_2 emission during the experiment(72 h) ranged from 1.35 to 5.67 g C m-2 in MCS, and from 1.11 to3.19 g Cm^(-2) in CLCS. Peak and average SR rates, as well as total carbon loss, were greater in MCS than in CLCS. Soil respiration rates of both MCS and CLCS were logarithmically correlated with gravimetric soil water content. Comparisons of SR among different precipitation events, together with the analysis of long-term precipitation data, suggest that small-size precipitation events have the potential for large short-term carbon losses, and that biological soil crusts might significantly contribute to soil CO_2 emission in the water-limited desert ecosystem.

关键词： biological soil crusts C cycling CO2 emission desert ecosystem precipitation amount soil water content

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Design and modification of metal sulfide-based catalysts for lithiumsulfur batteries

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Particuology 2024年第3期86卷 86-100页

作者： Yufei Zhao Chuannan Geng Li Wang haotian yang Wei Lv Quan-Hong yang Nanoyang Group State Key Laboratory of Chemical EngineeringSchool of Chemical Engineering and TechnologyNational Industry-Education Integration Platform of Energy Storageand Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin UniversityTianjin300072China Shenzhen Geim Graphene Center Engineering Laboratory for Functionalized Carbon MaterialsTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen518055China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou350207China

Metal sulfide(MS)have good conductivity,strong adsorption ability,and excellent catalytic activity for the conversion of sulfur species,and thus,show great promise as the catalysts in LieS ***,the relationship between their properties and electrochemical performance is still ***,further in-depth discussions are required to improve their design in Li-S *** review systematically summarizes the basic structural and electrochemical properties of MSs and highlights the advantages that guarantee them as high-performance catalysts in Li-S ***,various modification strategies for MSs to enhance the catalytic activity,efficiency,and stability are also *** last,future opportunities for MS catalysts in Li-S batteries are proposed.

关键词： Lithium-sulfur battery Metal sulfide Catalysis

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Accurate attitude estimation of HB2 standard model based on QNCF in hypersonic wind tunnel test

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Chinese Journal of Aeronautics 2020年第1期33卷 64-72页

作者： haotian yang Bin ZHOU Qi WEI Xiong WANG Xiaobin XU Rong ZHANG Department of Precision Instrument Tsinghua UniversityBeijing 100084China Xi’an Research Institute of High Technology Xi’an 710025China Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China

The accuracy of the HB2 standard model attitude measurement has an important impact on the hypersonic wind tunnel data *** limited size of the model and the existence of external vibrations make it challenging to obtain real-time reliable attitude *** reduce the influence of attitude errors on test results,this paper proposes a Quaternion Nonlinear Complementary Filter(QNCF)attitude determination algorithm based on Microelectromechanical Inertial Measurement Unit(MEMS-IMU).Firstly,the threshold-based PI control strategy is adopted to eliminate noise effect according to the Acceleration Magnitude Detector(AMD).Then,the flexible quaternion method is updated to carry out attitude estimation which is operational and easy to be embedded in the Field Programmable Gate Array(FPGA).Finally,a high-precision three-axis turntable test and a hypersonic wind tunnel test are *** results show that the pitchroll attitude errors are within 0.05°and 0.08°in the high-precision three-axis turntable test in a calculation time of 100 s respectively,and the attitude error is within 0.3°after the elastic angle correction in the hypersonic wind tunnel *** proposed method can provide accurate real-time attitude reference for the analysis of the actual movement of the model,exhibiting certain engineering application value with robustness and simplicity.

关键词： Attitude determination MEMS Nonlinear complementary filter Quaternion Wind tunnel test

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Electro-optomechanical cooperative cooling of nanomechanical oscillator beyond resolved sideband regime

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Science China(Physics,Mechanics & Astronomy) 2020年第3期63卷 25-32页

作者： ZhongHui Yuan Dongyang Wang ChengHua Bai haotian yang HongFu Wang AiDong Zhu Department of Physics College of ScienceYanbian UniversityYanji 133002China Department of Physics Harbin Institute of TechnologyHarbin 150001China

We propose a ground-state cooling scheme for a nanomechanical oscillator(NMO)that interacts with an optical cavity via radiation pressure at one side and with a superconducting microwave cavity via a capacitor at the other *** driving these two cavities on their respective red sidebands with extra laser and microwave fields,the NMO’s dual cooling channel is created through electro-optomechanical *** from the conventional optomechanical system with a single optical cavity wherein ground-state cooling is limited in the resolved sideband,the proposed scheme allows the optical cavity to function in an unresolved sideband regime under the cooperation of a microwave cavity with a high quality factor,or vice *** a weak coupling regime we demonstrate that the NMO can be cooled to near its ground-state from a finite temperature with a cooling rate that is significantly faster than that of the single-cavity optomechanical *** heating process can be completely suppressed by the cooperation of the dual cooling channel by appropriately selecting the system’s *** a decreasing thermal phonon number,the numerical results of final mechanical occupancy gradually approach the analytical cooling limit.

关键词： electro-optomechanics superconducting microwave cavity ground-state cooling dual cooling channel

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Petrogenesis and Tectonic Implications of Jurassic Granites in the Xingcheng Area,Northeastern North China Craton

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1483-1492页

作者： MU Maosong yang Debin XU Wenliang QUAN Yikang HAO Leran yang haotian WANG Anqi College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural ResourcesChangchun 130061China

New integrated geochemical studies are reported for Jurassic granites of the Xingcheng area in the northeastern North China Craton.U-Pb zircon data indicate that the Huashan and Taili monzogranites were emplaced during the Early(189±2 Ma)and Late(155±1 Ma)Jurassic,*** are typical of high-K calc-alkaline series rocks and I-type granites,according to our whole-rock geochemical *** Early and Late Jurassic monzogranites show adakitic rock characteristics because of their high Sr contents(221-347 ppm)and Sr/Y ratios(28.7-37.5),and low Y contents(7.83-14.7 ppm).The Early Jurassic monzogranite samples have an(^(87)Sr/^(86)Sr)i ratio of 0.7046,ε_(Nd)(t)values of -11.62 to -11.51,and ε_(Hf)(t)values of -13.6 to-6.4,whereas the Late Jurassic monzogranites have higher(87Sr/86Sr)i ratios of 0.7069-0.7071and lower ε_(Nd)(t)(-20.65 to-20.46)and ε_(Hf)(t)(-27.6 to-20.0)*** suggest that the Early Jurassic adakitic rocks were derived from partial melting of thickened lower crust contaminated with mantle-derived materials,related to subduction of the Paleo-Pacific *** Late Jurassic adakitic rocks were derived from partial melting of thickened lower crust in an extensional tectonic setting associated with an active continental margin.

关键词： geochemistry petrology monzogranite adakite North China Craton

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Detrital zircon geochronology and provenance of sediments within the Mesozoic basins:New insights into tectonic evolution of the Qinling Orogen

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Geoscience Frontiers 2021年第3期12卷 343-357页

作者： Anqi Wang Debin yang haotian yang Maosong Mu Yikang Quan Leran Hao Wenliang Xu College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural ResourcesChangchun 130061China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

Mesozoic sedimentary units within the Nanzhao and Mashiping basins record the paleogeographic and tectonic evolution of the Qinling Orogen(QO).This study uses new detrital zircon U-Pb ages and Hf isotopic data to constrain the timing of deposition and provenance of the Taishanmiao,Taizishan,Nanzhao,and Mashiping formations of the North Qinling Orogen(NQO).The detrital zircons can be split by age peaks into five major groups,including Early Cretaceous,Late Triassic,Early Paleozoic,Neoproterozoic and Paleoproterozoic age *** the basis of the youngest zircon ages and age-diagnostic fossils,we conclude that the Taishanmiao(youngest age of 234 Ma)and Taizishan(216 Ma)formations were deposited during the Late Triassic,whereas the Nanzhao Formation(110 Ma)was deposited during the Early Cretaceous rather than the Late Jurassic as previously *** Mashiping Formation(110 Ma)was also deposited during the Early *** with zircon Hf isotopic compositions,zircons from Late Triassic units were generally derived from the NQO,South Qinling Orogen(SQO),and North China Craton(NCC),with minor amounts derived from the Xing-Meng Orogenic *** sediments within the Nanzhao Formation were mainly derived from the QO,with a minor contribution from the *** Early Cretaceous conglomerates of the Mashiping Formation were generally derived from recycled earlier *** implies that Late Triassic deposition was related to the final closure of the Mianlue Ocean,whereas Early Cretaceous deposition was correlated to the continued intercontinental subduction of the yangtze Craton beneath the *** change in provenance within these Mesozoic sediments suggests the QO underwent two periods of significant uplift,which was a process generated sediments that were deposited in a series of basins of this area.

关键词： Detrital zircons U-Pb dating Hf isotopes Mesozoic Qinling Orogen

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Recharge processes limit the resource elements of Qarhan Salt Lake in western China and analogues in the evaporite basins

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Journal of Oceanology and Limnology 2023年第4期41卷 1226-1242页

作者： Hualing SONG Qishun FAN Qingkuan LI Tianyuan CHEN haotian yang Chunmei HAN Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Xining 810008China University of Chinese Academy of Sciences Beijing 100049China

The Qarhan Salt Lake(QSL)in western China is K-Sr-Li-B-Br-Rb multi-resource coexisting Quaternary brine *** research efforts have been directed to the origin of K-Li resources and evolutionary history of the ***,the study on the different sources,recharge processes,and differential distribution patterns for these resource elements in brine deposits is still ***,we measured Li-B concentrations and H-O-Sr-B isotopic compositions of different waters(river,spring,and brine)from the QSL,combined with the reported K-Sr contents and multiple isotopes of waters,to discuss the recharge,source of K-Sr-Li-B and their spatial distributions,by analogy with other evaporite basins in the *** results show that:(1)the K-Li-B-Sr elemental concentrations of brines and their spatial distribution in the QSL are diverse;(2)high K and Sr values are distributed in Dabuxun and Qarhan sections,respectively,which are controlled by Ca-Cl springs in the northern QSL;on the contrary,Li and B values are enriched in the Bieletan section and are charged by thermal springs in the Kunlun Mountains;(3)the formation and evolution of Ca-Cl and thermal springs constrain fundamentally on the recharge processes of K-Sr and Li-B elements in the terminal salt lakes of the Qaidam Basin(QB);(4)some analogues of recharge processes limit the resource elements of the QSL and other salt lakes(Da Qaidam,Lop Nur,Zhabuye,Atacama,and Guayatayoc)in the world provides a reference for the resource exploration in deep formation waters in the evaporite basins.

关键词： K-Sr-Li-B elements differential distribution recharge process Qarhan Salt Lake(QSL) analogue

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Influencing mechanism and hydrogeological implications of water level fluctuation of lakes in the northern Qaidam Basin,Qinghai-Tibet Plateau

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Journal of Oceanology and Limnology 2023年第4期41卷 1243-1257页

作者： Yaping CHENG Qishun FAN Tianyuan CHEN haotian yang Qingkuan LI Chunmei HAN Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Xining 810008China University of Chinese Academy of Sciences Beijing 100049China

The Qaidam Basin(QB)is a concentrated distribution area and chemical industrial bases of salt lakes in *** in the QB have been expanding during the past 20 *** lake expansion resulted in some considerable scientific issues on the protection of salt lake resources and infrastructure,and monitoring of hydrological processes at the lake-basin *** the spatial-temporal trends of lake changes on the Qinghai-Tibet Plateau(QTP)have been well documented,the underlying influencing mechanism and hydrogeological implications of rapid lake changes in the QB are not well *** lakes in the northern QB were selected to investigate lake water level fluctuations on different time scales based on extensive in-situ monitoring and satellite *** influencing mechanism and hydrogeological implications of rapid changes of terminal lakes were discussed in combination with the reported increasing precipitation rate and mass balance of glaciers in the northern *** reveal the following:(1)the fluctuation pattern of Sugan Lake was asynchronous and out of phase with that of Xiao Qaidam and Toson lakes during the monitoring period;(2)Sugan Lake water rose gradually,and the rise interval was from late April to early *** contrast,Xiao Qaidam and Toson lakes took on a rapid and steep rise,and the rise intervalwas from late July to September;(3)the influencing mechanisms for rapid lake fluctuations are controlled by different factors:glacier and snow melting with increasing temperature for Sugan Lake and increasing precipitation for Xiao Qaidam and Toson lakes;(4)in accordance with different intervals and influencing mechanisms of rapid lake expansions in the QB,hydrological risk precaution of lakes and corresponding river catchments was conducted in different parts of the *** study provided an important scientific basis for assessing the hydrological process and hydrological risk precaution,and protection of salt lake resources al

关键词： lake level fluctuation influencing mechanism hydrogeological implication northern Qaidam Basin in-situ monitoring

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Soil water repellency and influencing factors of Nitraria tangutorun nebkhas at different succession stages

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Journal of Arid Land 2014年第3期6卷 300-310页

作者： haotian yang XinRong LI LiChao LIU YanHong GAO Gang LI RongLiang JIA Shapotou Desert Research and Experiment Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Abstract： Soil water repellency （WR） is an important physical characteristic of soil surface. It is capable of largely influencing the hydrological and geomorphological processes of soil, as well as affecting the ecological processes of plants, such as growth and seed germination, and has thus been a hot topic in recent research around the world. In this paper, the capillary rise method was used to study the soil WR characteristics of Nitraria tangutorun nebkhas. Soil water repellencies at different succession stages of Nitraria tangutorun were investigated, and the relationships between soil WR and soil organic matter, total N, and total P, soil texture, pH, and concentrations of CO32, HCO3-, CI, SO42-, Na~, K~, Ca2~ and Mg2＋ were discussed. Soil WR may be demonstrated at the following nebkhas dune evolvement stages： extremely degraded〉degraded〉stabilized〉well developed〉newly developed〉quick sand. Apart from some soil at the bottom, the WR of other soils （crest and slope of dune） was found to be largest at the topsoil, and decreased as the soil depth increased. The results showed that multiple factors affected soil WR characteristics e.g. WR increased significantly as the contents of soil organic matter and total N increased, but did not change as the total P content increased. Soil texture was a key factor affecting soil WR; soil WR increased significantly as clay content increased, and decreased significantly as sand content increased. Low pH was shown to be more suitable for the occurrence of soil WR. Four cations （Ca2＋, Mg2＋, K＋ and Na＋） and two anions （CI and SO42） enhanced soil WR, while CO32-decreased it. HCO3- did not show any observable effect. Finally, we established a best-fit general linear model （GLM） between soil-air-water contact angle （CA） and influencing factors （CA=5.606 sand＋6.496 （clay and silt）-2.353 pH＋470.089 CQ2＋11.346 Na＋-407.707 Cl--14.245 SO42-＋0.734 total N-519.521 ）. It was concluded that all soils contain subcritical WR （0°〈CA〈90°）. Th

关键词： hydrophobicity soil-air-water contact angle capillary rise method Nitraria tangutorun nebkhas vegetation succession stage

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Effects of fertilization on population density and productivity of herbaceous plants in desert steppe

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Research in Cold and Arid Regions 2014年第3期6卷 219-225页

作者： JieQiong Su XinRong Li haotian yang Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences

In order to investigate the impacts of fertilization on population density and productivity on herbaceous plants in desert steppe, nitrogen （N）, phosphorus （P）, and N-P addition experiments were performed. Each fertilizer treatment included four addition levels, i.e., 0, 5, 10, and 20 g/m2. The results indicated that population density decreased as fertilization levels increased regardless of the sort of fertilizer. More specifically, total density as well as density ofArtemisia capillaris, Allium polyrhizum, and Enneapogon brachystachyus decreased significantly in 20 g/m2 treated plots, as compared with the control plots. Fertilization effects on aboveground and root biomasses were extremely similar to that found in population density; that is, both total aboveground biomass and aboveground biomasses for A. capillaris, A. polyrhizum, and E. brachystachyus were negatively correlated with increasing fertilization levels, with all determination coefficients （R2） greater than 0.80. Therefore, in the case of desert regions （annual precipitation 〈180 mm）, fertilization would inhibit population density and productivity of herbaceous plants.

关键词： desert steppe herbaceous vegetation nitrogen fertilizer phosphorus fertilizer biomass

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