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14.1 W continuous-wave dual-end diode-pumped Er:Lu_(2)O_(3)laser at 2.85μm

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Chinese Optics Letters 2024年第1期22卷 84-89页

作者：梁洋洋李涛张百涛何京良 Sascha Kalusniak 赵显 Christian Kränkel Key Laboratory of Laser&Infrared System Ministry of EducationShandong UniversityQingdao 266237China School of Information Science and Engineering Shandong Provincial Key Laboratory of Laser Technology and ApplicationShandong UniversityQingdao 266237China institute of Novel Semiconductors State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Leibniz-Institut für Kristallzüchtung(IKZ) Berlin 12489Germany

We present our efforts towards power scaling of Er:Lu_(2)O_(3)lasers at 2.85μ*** applying a dual-end diode-pumped resonator scheme,we achieve an output power of 14.1 W at an absorbed pump power of 59.7 W with a slope efficiency of 26%.In a single-end pumped resonator scheme,an output power of 10.1 W is reached under 41.9 W of absorbed pump *** the best of our knowledge,this is the first single crystalline mid-infrared rare-earth-based solid-state laser with an output power exceeding 10 W at room temperature.

关键词： high-power continuous-wave laser mid-infrared laser dual-end pump scheme

Wood anatomy chronologies of Scots pine in the foothills of the Western Sayan(Siberia)

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Journal of Forestry Research 2024年第3期35卷 13-27页

作者： Elena A.Babushkina Dmitry R.Dergunov Mikhail S.Zharkov Liliana V.Belokopytova Dina F.Zhirnova Bao Yang Jingjing Liu Xiaomei Peng Eugene A.Vaganov Khakass Technical institute Siberian Federal UniversityAbakan 655017Russia institute of Ecology and Geography Siberian Federal UniversityKrasnoyarsk 660036Russia Mathematical Methods and IT Department Siberian Federal UniversityKrasnoyarsk 660036Russia Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093People's Republic of China Department of Dendroecology V.N.Sukachev Institute of ForestSiberian Branch of the Russian Academy of ScienceKrasnoyarsk 660036Russia

Recent methodological advances in quantitative wood anatomy have provided new insights into the climatic responses of radial growth at the scale of cell structure of tree rings. This study considered long-term chronologies of tracheid measurements, indexed by a novel approach to separate their specific climatic responses from signal recorded in cell production(closely reflected in tree-ring width). To fill gaps in understanding the impact of climate on conifer xylem structure, Scots pine(Pinus sylvestris L.)trees > 200 years old were selected within the forest-steppe zone in southern Siberia. Such habitats undergo mild moisture deficits and the resulting climatic regulation of growth processes. Mean and maximum values of cell radial diameter and cell wall thickness were recorded for each tree *** a low level of climatogenic stress, components of cell chronologies independent of cambial activity were separated to obtain significant climatic signals revealing the timing of the specific stages of tracheid differentiation. Cell expansion lasted from mid-April to July and was impacted similarly to tree-ring width(stimulated by precipitation and stressed by heat), maximum cell size formed late June. A switch in the climatic responses of mean anatomical traits indicated transition to latewood in mid-July. Secondary wall deposition lasted until mid-September, suppressed by end of season temperatures. Generally, anatomical climatic responses were modulated by a less dry May and September compared with summer months.

关键词： Quantitative wood anatomy Cell radial size Cell wall thickness Pinus sylvestris Climatic response

Two thin middle-crust low-velocity zones imaged in the Chuan-Dian region of southeastern Tibetan Plateau and their tectonic implications

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Science China Earth Sciences 2024年第5期67卷 1675-1686页

作者： Long LI Xin WANG Guangbing HOU Yuan LING Yinshuang AI Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China

Intracrustal low-velocity zones(LVZs)indicate a mechanically weak crust and are widely observed in the southeast margin of the Tibetan ***,their spatial distributions and formation mechanisms remain *** investigate their distribution and detailed morphology of the LVZs in the southeastern Tibetan Plateau,here we used teleseismic events and continuous waveform data recorded by 40 broadband seismic stations newly deployed in the Sichuan-Yunnan region from December 2018 to October 2020.A total of 12,924 high-quality P-wave receiver functions and 5–40 s fundamental Rayleigh surface wave phase velocity dispersion curves from ambient noise cross-correlation functions were *** Swave velocity model at a depth interval of 0–100 km in the study area was inverted by using the trans-dimensional Markov chain Monte Carlo strategy to jointly invert the complementary data of the receiver function waveform and Rayleigh surface wave phase velocity *** results show that there are two separate LVZs(~3.5 km/s)surrounding the rigid Daliangshan subblock at crustal depths of approximately 30–40 km,providing new constraints on the geometry of the LVZs in our study *** two LVZs obtained in this study may represent the middle crustal flow channels,through which the material in the center of the Tibetan Plateau extrudes to its southeast *** by the rigid Sichuan Basin and the spindle-like Daliangshan subblock,the material continues to flow southward through the mechanically weak middle crustal channels surrounding the Daliangshan *** addition,the existence of thin LVZs in the middle crust plays an important role in understanding the decoupling between the upper and lower crust in the study *** also provides new constraint on the complex tectonic deformation process of the southeastern margin of the Tibetan Plateau caused by the collision and compression of the Indian and the Eurasian plates.

关键词： Southeastern Tibetan Plateau Joint inversion Intracrustal low-velocity zone mid-crustal channel flow

High-resolution mid-infrared single-photon upconversion ranging

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Photonics Research 2024年第6期12卷 1294-1302页

作者： SHUHONG JIANG KUN HUANG TINGTING YU JIANAN FANG BEN SUN YAN LIANG QIANG HAO E.WU MING YAN HEPING ZENG State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401121China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China School of Optical Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Research Center for Quantum Sciences Shanghai 201315China Guangyang Bay Laboratory Chongqing Institute for Brain and IntelligenceChongqing 400064China

Single-photon laser ranging has widespread applications in remote sensing and target ***,highly sensitive light detection and ranging(lidar)has long been restricted in the visible or near-infrared *** appealing quest is to extend the operation wavelength into the mid-infrared(MIR)region,which calls for an infrared photon-counting system at high detection sensitivity and precise temporal ***,we devise and demonstrate an MIR upconversion lidar based on nonlinear asynchronous optical ***,the infrared probe is interrogated in a nonlinear crystal by a train of pump pulses at a slightly different repetition rate,which favors temporal optical scanning at a picosecond timing resolution and a kilohertz refreshing rate ***,the cross-correlation upconversion trace is temporally stretched by a factor of 2×10^(4),which can thus be recorded by a low-bandwidth silicon *** combination with the time-correlated photon-counting technique,the achieved effective resolution is about two orders of magnitude better than the timing jitter of the detector itself,which facilitates a ranging precision of 4μm under a low detected flux of 8×10^(−5) photons per *** presented MIR time-of-flight range finder is featured with single-photon sensitivity and high positioning resolution,which would be particularly useful in infrared sensing and imaging in photon-starved scenarios.

关键词： resolution lidar repetition

The mid-domain effect in flowering phenology

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Plant Diversity 2024年第4期46卷 502-509页

作者： Yanjun Du Rongchen Zhang Xinran Tang Xinyang Wang Lingfeng Mao Guoke Chen Jiangshan Lai Keping Ma School of Tropical Agriculture and Forestry(School of Agricultural and Rural Affairs School of Rural Revitalization)Hainan UniversityHaikou 570228China HNU-ASU Joint International Tourism College Hainan UniversityHaikou 570228China School of Ecological and Environmental Sciences East China Normal UniversityShanghai 200062China College of Ecology and Environment Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

The timing of flowering is an important driver of species distribution and community assembly ***,we still have much to learn about the factors that shape flowering diversity(i.e.,number of species flowering per period) in plant *** potential explanation of flowering diversity is the mid-domain effect,which states that geometric constraints on species ranges within a bounded domain(space or time) will yield a mid-domain peak in diversity regardless of ecological ***,we determine whether the mid-domain effect explains peak flowering time(i.e.,when most species of communities are flowering) across *** used phenological data of 16,267 herbaceous and woody species from the provincial Flora in China and species distribution data from the Chinese Vascular Plant Distribution Database to determine relationships between the observed number of species flowering and the number of species flowering as predicted by the mid-domain effect model,as well as between three climatic variables(mean minimum monthly temperature,mean monthly precipitation,and mean monthly sunshine duration).We found that the mid-domain effect explained a significant proportion of the temporal variation in flowering diversity across all species in ***,the mid-domain effect explained a greater proportion of variance in flowering diversity at higher latitudes than at lower *** patterns of flowering diversity for both herbaceous and woody species were related to both the mid-domain effect and environmental *** findings indicate that including geometric constraints in conjunction with abiotic and biotic predictors will improve predictions of flowering diversity patterns.

关键词： Flowering diversity Functional biogeography Latitudinal gradient Macroecology Macrophenology Null model

Spectral Selectivity of CdTe Cells with Substrate Configuration for Photovoltaic/Thermal Applications

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Journal of Thermal Science 2024年第4期33卷 1542-1553页

作者： CHEN Ken HU Kongfu ZHAO Bin CHEN Tao HAO Yong PEI Gang Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei230027China Key Laboratory of Solar Thermal Conversion of Anhui Province Hefei230027China Hefei National Laboratory for Physical Sciences at Microscale Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei230026China institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

Existing photovoltaic cells with high infrared emissivity generate huge radiative heat loss in photovoltaic/thermal applications and degrade the photothermal *** purpose of this work is to evaluate the full spectral absorptivity of CdTe cells to find a spectrally selective photovoltaic cell for photovoltaic/thermal *** this end,the solar absorptivity and mid-infrared thermal emissivity of CdTe cells were tested by ellipsometry,UV-Vis-NIR spectrophotometer,and Fourier transform infrared *** experimental results show that the AM 1.5 solar spectrum weighted absorptivity of the substrate configuration CdTe cell reaches 0.91,and the mid-infrared emissivity is only 0.29,while the superstrate configuration cell emissivity is as high as *** research shows that substrate configuration with a transparent conductive layer on top can be flexibly grown on metal foils and has spectral selectivity with high solar absorptivity and low mid-infrared emissivity should be considered in the future for photovoltaic/thermal applications.

关键词： photovoltaic/thermal spectral selectivity substrate configuration CdTe cell ITO

The unimodal latitudinal pattern of K,Ca and Mg concentration and its potential drivers in forest foliage in eastern China

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Forest Ecosystems 2024年第3期11卷 318-328页

作者： Zhijuan Shi Sining Liu Yahan Chen Dongdong Ding Wenxuan Han Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing100193China Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province&National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River College of ForestrySichuan Agricultural UniversityChengdu611130China institute of Botany Chinese Academy of SciencesBeijing100093China

Potassium(K),calcium(Ca),and magnesium(Mg)are essential elements with important physiological functions in *** studies showed that leaf K,Ca,and Mg concentrations generally increase with increasing ***,recent meta-analyses suggested the possibility of a unimodal pattern in the concentrations of these elements along latitudinal *** authenticity of this unimodal latitudinal pattern,however,requires validation through large-scale field experimental data,and exploration of the underlying mechanisms if the pattern is ***,we collected leaves of common species of woody plants from 19 montane forests in the north-south transect of eastern China,including 322 species from 160 genera,67 families;and then determined leaf K,Ca,and Mg concentrations to explore their latitudinal patterns and driving *** results support unimodal latitudinal patterns for all three elements in woody plants across eastern China,with peak values at latitude 36.5±1.0°*** shift of plant-functional-type compositions from evergreen broadleaves to deciduous broadleaves and to conifers along this latitudinal span was the key factor contributing to these *** factors,mainly temperature,and to a lesser extent solar radiation and precipitation,were the main environmental *** factors,by altering the composition of plant communities and regulating plant physiological activities,influence the latitudinal patterns of plant nutrient *** findings also suggest that high leaf K,Ca,and Mg concentrations may represent an adaptive strategy for plants to withstand water stress,which might be used to predict plant nutrient responses to climate changes at large scales,and broaden the understanding of biogeochemical cycling of K,Ca,and Mg.

关键词： Potassium Calcium Magnesium mid-latitudes Latitudinal pattern Plant functional type Water stress Woody plant

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Elevation of basal lacustrine sediments along the mid-lower reaches of the Yangtze River and its implications for the reconstruction of Holocene water levels

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Science China Earth Sciences 2024年第9期67卷 2924-2936页

作者： Shuchun YAO Chunhai LI Bin XUE Nanjing institute of Geography and Limnology Chinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The middle and lower reaches of the Yangtze River,a primary region for freshwater lakes in China,have undergone significant transformations throughout the *** changes,driven by factors such as sea-level rise,climate change,and human activities,have led to the progressive elevation of water levels in this *** a result,a floodplain has emerged,characterized by the formation of numerous shallow lakes along the river ***,the pattern of water-level changes in the main channel of the Yangtze River during the Holocene remains *** gap in knowledge poses challenges for understanding sediment transport dynamics,the interactions between the river and its adjacent lakes,and the prevention and control of flood disasters in the Yangtze River *** shed light on these issues,our study compiled data on the surface elevation and water depth of 81 lakes in the mid-lower reaches of the Yangtze River ***,we analyzed historical water-level records from the 1900s to the 1970s at eight gauging stations from Shashi to Jiangyin along the river’s main *** findings reveal that,particularly along the Jingjiang section,the basal elevation of most lakes is lower than the Yangtze River’s water level during the dry ***,the water level of the main stream exceeds that of both the floodplain and the lakes enclosed by the Jingjiang *** the tidal reach,especially within the Taihu Lake basin,the basal elevation of lakes typically falls below sea ***,lakes located along the section from Chenglingji to Wuhu exhibit basal elevations that correspond with the Yangtze River’s annual average and dry season water *** the widespread presence of lakes along the middle and lower reaches of the Yangtze River,our study introduces a new proxy for reconstructing the mean water level of the mid-lower Yangtze River in the *** analyzing sediments from Nanyi Lake and Chenyao Lake in the lower Yangtze River,we a

关键词： middle and lower Yangtze River Holocene Water level Floodplain lakes Basal sediment elevation

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Projected changes in Köppen-Trewartha climate zones under 1.5-4℃global warming targets over mid-high latitudes of Northern Asia using an ensemble of RegCM4 simulations

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Advances in Climate Change Research 2024年第2期15卷 185-196页

作者： Jie WU Xue-Jie GAO Xian-Bing TANG Filippo GIORGI School of Geography and Environmental Engineering Gannan Normal UniversityGanzhou 341000China Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100049China The Abdus Salam International Centre for Theoretical Physics Trieste 34100Italy

mid-high latitude Northern Asia is one of the most vulnerable and sensitive areas to global warming,but relatively less studied *** used an ensemble of a regional climate model(RegCM4)projections to assess future changes in surface air temperature,precipitation and Köppen-Trewartha(K-T)climate types in Northern Asia under the 1.5-4℃global warming ***4 is driven by five CMIP5 global models over an East Asia domain at a grid spacing of 25 *** of the present day(1986-2005)simulations shows that the ensembles of RegCM4(ensR)and driving GCMs(ensG)reproduce the major characters of the observed temperature,precipitation and K-T climate zones reasonably *** and more realistic spatial detail is found in RegCM4 compared to the driving GCMs.A general warming and overall increases in precipitation are projected over the region,with these changes being more pronounced at higher warming *** projected warming by ensR shows different spatial patterns,and is in general lower,compared to ensG in most months of the year,while the percentage increases of precipitation are maximum during the cold *** future changes in K-T climate zones are characterized by a substantial expansion of Dc(temperature oceanic)and retreat of Ec(sub-arctic continental)over the region,reaching∼20%under the 4℃warming *** most notable change in climate types in ensR is found over Japan(∼60%),followed by Southern Siberia,Mongolia,and the Korean Peninsula(∼40%).The largest change in the K-T climate types is found when increasing from 2 to 3℃.The results will help to better assess the impacts of climate change and in implementation of appropriate adaptation measures over the region.

关键词： mid-high latitudes of Northern Asia Köppen climate zones Global warming targets Regional climate model