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1Energy balance closure at ChinaFLUX sites显示文摘Network of eddy covariance observation is measuring long-term carbon and water fluxes in contrasting ecosystems and climates. As one important reference of independently evaluating scalar flux estimates from eddy covariance, energy balance closure is used widely in study of carbon and water fluxes. Energy balance closure in ChinaFLUX was evaluated by statistical regression of turbulent energy fluxes (sensible and latent heat) against available energy (net radiation, soil heat flux, canopy heat storage) and the energy balance ratio (EBR) and the frequency distribution of relative errors of energy balance (δ). The trends of diurnal and seasonal variation of energy balance in ChinaFLUX were analyzed. The results indicated that the imbalance was prevalent in all observation sites, but there were little differences among sites because of the properties variation of sites. The imbalance was greater during nocturnal periods than daytime and closure was improved with friction velocity intensifying. Generally the results suggested that estimates of the scalar turbulent fluxes of sensible and latent heat were underestimated and/or that available energy was overestimated. Finally, we discussed certain factors that are contributed to the imbalance of energy, such as systematic errors associated with the sampling mismatch, systematic instrument bias, neglected energy sinks, low and high frequency loss of turbulent fluxes and advection of heat and water vapor.LI Zhengquan, YU Guirui, WEN Xuefa, ZHANG Leiming, REN Chuanyou & FU Yuling Chinese Ecosystem Research Network Synthesis Research Center, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 2005Science China Earth Sciences2005,48,z1:50
2Altered trends in carbon uptake in China’s terrestrial ecosystems under the enhanced summer monsoon and warming hiatus显示文摘The carbon budgets in terrestrial ecosystems in China are strongly coupled with climate changes.Over the past decade,China has experienced dramatic climate changes characterized by enhanced summer monsoon and decelerated warming.However,the changes in the trends of terrestrial net ecosystem production(NEP)in China under climate changes are not well documented.Here,we used three ecosystem models to simulate the spatiotemporal variations in China's NEP during 1982–2010 and quantify the contribution of the strengthened summer monsoon and warming hiatus to the NEP variations in four distinct climatic regions of the country.Our results revealed a decadal-scale shift in NEP from a downtrend of–5.95 Tg C/yr^2(reduced sink)during 1982–2000 to an uptrend of 14.22 Tg C/yr^2(enhanced sink)during 2000–10.This shift was essentially induced by the strengthened summer monsoon,which stimulated carbon uptake,and the warming hiatus,which lessened the decrease in the NEP trend.Compared to the contribution of 56.3%by the climate effect,atmospheric CO2 concentration and nitrogen deposition had relatively small contributions(8.6 and 11.3%,respectively)to the shift.In conclusion,within the context of the global-warming hiatus,the strengthening of the summer monsoon is a critical climate factor that enhances carbon uptake in China due to the asymmetric response of photosynthesis and respiration.Our study not only revealed the shift in ecosystem carbon sequestration in China in recent decades,but also provides some insight for understanding ecosystem carbon dynamics in other monsoonal areas.Honglin He Shaoqiang Wang Li Zhang Junbang Wang Xiaoli Ren Lei Zhou Shilong Piao Hao Yan Weimin Ju Fengxue Gu Shiyong Yu Yuanhe Yang Miaomiao Wang Zhongen Niu Rcmg Ge Huimin Yan Mei Huang Guoyi Zhou Yongfei Bai Zongqiang Xie Zhiyao Tang Bingfang Wu Leiming Zhang Nianpeng He Qiufeng Wang Guirui Yu 2019National Science Review2019,6,3:24
3Advances in carbon flux observation and research in Asia显示文摘As an important component of FLUXNET, Asia is increasingly becoming the hotspot in global carbon research for its vast territory, complex climate type and vegetation diversity. The present three regional flux observation networks in Asia (i.e. AsiaFlux, KoFlux and ChinaFLUX)have 54 flux observation sites altogether, covering tropic rainforest, evergreen broad-leaved forest, broad-leaved and coniferous mixed forest, shrubland, grassland, alpine meadow and cropland ecosystems with a latitudinal distribution from 2°N to 63°N. Long-term and continuous fluxes of carbon dioxide, water vapor and energy between the biosphere and atmosphere are mainly measured with eddy covariance technique to (1) quantify and compare the carbon, water and energy budgets across diverse ecosystems; (2) quantify the environmental and biotic controlling mechanism on ecosystem carbon, water and energy fluxes; (3) validate the soil-vegetation-atmosphere model; and (4) serve the integrated study of terrestrial ecosystem carbon and water cycle. Over the last decades, great advancements have been made in the theory and technology of flux measurement, ecosystem flux patterns, simulation and scale conversion by Asian flux community. The establishment of ChinaFLUX has greatly filled the gap of flux observation and research in Eurasia. To further promote the flux measurement and research,accelerate data sharing and improve the data quality, it is necessary to present a methodological system of flux estimation and evaluation over complex terrain and to develop the integrated research that combines the flux measurement, stable isotope measurement, remote sensing observation and GIS technique. It also requires the establishment of the Joint Committee of Asian Flux Network in the Asia-Pacific region in order to promote the cooperation and communication of ideas and data by supporting project scientists, workshops and visiting scientists.YU Guirui, ZHANG Leiming, SUN Xiaomin, FU Yuling & LI Zhengquan Synthesis Center of Chinese Ecosystem Research Network (CERN), Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 2005Science China Earth Sciences2005,48,z1:16
4Observation and analysis of near-surface atmospheric aerosol optical properties in urban Beijing显示文摘Year-round measurements of the mass concentration and optical properties of fine aerosols(PM_(2.5)) from June 2009 to May 2010 at an urban site in Beijing were analyzed.The annual mean values of the PM_(2.5) mass concentration,absorption coefficient(Ab),scattering coefficient(Sc) and single scattering albedo(SSA)at 525 nm were 67±66μg/m^3,64 ±62 Mm^(-1),360 ±405 Mm^(-1) and 0.82 ±0.09,respectively.The bulk mass absorption efficiency and scattering efficiency of the PM_(2.5) at 525 nm were 0.78 m^2/g and 5.55 m^2/g,respectively.The Ab and Sc showed a similar diurnal variation with a maximum at night and a minimum in the afternoon,whereas SSA displayed an opposite diurnal pattern.Significant increases in the Ab and Sc were observed in pollution episodes caused by the accumulation of pollutants from both local and regional sources under unfavorable weather conditions.Aerosol loadings in dust events increased by several times in the spring,which had limited effects on the Ab and Sc due to the low absorption and scattering efficiency of dust particles.The frequency of haze days was the highest in autumn because of the high aerosol absorption and scattering under unfavorable weather conditions.The daily PM_(2.5)concentration should be controlled to a level lower than 64 μg/m^3 to prevent the occurrence of haze days according to its exponentially decreased relationship with visibility.Junshan Jing Yunfei Wu Jun Tao Huizheng Che Xiangao Xia Xiaochun Zhang Peng Yan Deming Zhao Leiming Zhang 2015Particuology2015,13,1:16
5A comprehensive review on proppant technologies显示文摘The main function of traditional proppants is to provide and maintain conductive fractures during well production where proppants should meet closure stress requirement and show resistance to diagenesis under downhole conditions.Many different proppants have been developed in the oil&gas industry,with various types,sizes,shapes,and applications.While most proppants are simply made of silica or ceramics,advanced proppants like ultra-lightweight proppant is also desirable since it reduces proppant settling and requires low viscosity fluids to transport.Additionally,multifunctional proppants may be used as a crude way to detect hydraulic fracture geometry or as matrices to slowly release downhole chemical additives,besides their basic function of maintaining conductive hydraulic fractures.Different from the conventional approach where proppant is pumped downhole in frac fluids,a revolutionary way to generate in-situ spherical proppants has been reported recently.This paper presents a comprehensive review of over 100 papers published in the past several decades on the subject.The objectives of this review study are to provide an overview of current proppant technologies,including different types,compositions,and shapes of proppants,new technologies to pump and organize proppants downhole such as channel fracturing,and also in-situ proppant generation.Finally,the paper sheds light on the current challenges and emphasizes needs for new proppant development for unconventional resources.Feng Liang Mohammed Sayed Ghaithan A.Al-Muntasheri Frank F.Chang Leiming Li 2016Petroleum2016,2,1:15
6Seasonal patterns and environmental control of ecosystem respiration in subtropical and temperate forests in China显示文摘Continuous measurement of carbon dioxide exchange using the eddy covariance (EC) technique was made at two ChinaFLUX forest sites including the young subtropical Pinus plantation (Qianyanzhou) and old temperate broad-leaved Korean pine mixed forest (Changbai Mountains) as part of the ChinaFLUX network. Seasonal patterns and environmental control of ecosystem respiration in the subtropical and temperate forests were evaluated by the often-used multiplicative model and Q10 model as a function of temperature and soil water content. The resuits suggested that ( i ) temperature was found to be a dominant factor in the ecosystem respiration, and most of the temporal variability of ecosystem respiration was explained by temperature. However, in the drought-stressed ecosystem, soil water content controlled the temporal variability of ecosystem respiration other than temperature effects, and soil water content became a dominat factor when severe drought affected the ecosystem respiration; (ii) the regression models analysis revealed that in the drier soil, ecosystem respiration was more sensitive to soil moisture than was expressed by the often-used multiplicative model. It was possible to accurately estimate the seasonal variation of ecosystem respiration based on the Q10 model; and (iii)annual ecosystem respiration derived from the often-used multiplicative model was 1209 g C m-2and 1303 g C m-2, and was consistently a little higher than the Q10 model estimates of 1197 g C m-2 and 1268 g C m-2 for Qianyanzhou and Changbai Mountains, respectively.YU Guirui, WEN Xuefa, LI Qingkang, ZHANG Leiming, REN Chuanyou, LIU Yunfen & GUAN Dexin Chinese Ecosystem Research Network Synthesis Research Center, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 2005Science China Earth Sciences2005,48,z1:13
7New data regarding acritarch biostratigraphy from the Early-Middle Cambrian Kaili Formation in Chuandong,Guizhou Province,China显示文摘Previous studies had evaluated acritarchs from the Balang and Pingzhai sections of the Early-Middle Cambrian Kaili Formation in east Guizhou,China.The results of these studies suggest that the acritarchs in these sections have potential biostratigraphic significance.More recently,34 samples collected from 83 m lower part of the Lower-Middle Cambrian Kaili Formation in the Jianshan section of Chuandong,Guizhou Province were prepared for palynological analysis.Analysis of these samples revealed a distinct change in the acritarch assemblages at the bed,which was approximately 46 m above the bottom of the Kaili Formation.These findings suggest a boundary represented by an important alteration of the ecological environment.In addition,the position of the acritarch biostratigraphic change is somewhat higher than the boundary between Cambrian Series 2 and Series 3 based on trilobites found in the same section.This indicates that the distinct change in acritarch assemblages is similar to the change in trilobite assemblages that occurs around the boundary between Cambrian Series 2 and Series 3.Therefore,acritarch biostratigraphy can provide data that can be used to define the base of Cambrian Series 3 in this region,and possibly worldwide.Leiming Yin Ruidong Yang Jin Peng Fanfan Kong 2009Progress in Natural Science:Materials International2009,19,1:9
8New observations on spicule-like structures from Dou-shantuo phosphorites at Weng'an,Guizhou Province显示文摘Doushantuo phosphorites at Weng’an, Guizhou Province, provide a unique opportunity for the study of early evolution of multicellular organisms, including metazoans. Our light microscope and SEM observations, however, do not substantiate a sponge spicule interpretation of spicular structures. No convincing axial canals have been seen in the observed spicule population. Instead, the coexistence of some monaxonal spicules with clearly diagenetic crystal fascicles and dumbbells suggest that these monaxons may also be diagenetic in origin. Our preliminary EDS analyses detect no significant silicon in spicule-containing intraclasts (including abiotic clasts and fragments of sphaeromorphic acritarchs and algal thalli), that contain abundant monaxonal spicular structures. We, therefore, believe that the evidence for a sponge spicule interpretation of the Doushantuo spicular structures are at best ambiguous at present; these alleged sponge spicules are indistinguishable from coexistent diagenetic crystals.Leiming Yin Shuhai Xiao Xunlai Yuan 2001Chinese Science Bulletin2001,46,21:8
9中国地区大气汞沉降速度研究显示文摘借助箱模式对汞的干沉降过程进行敏感性分析,并利用区域大气环境模式系统Reg AEMS计算中国地区汞干沉降速度的时空分布特征。结果表明,森林下垫面下三类汞(气态零价汞、活性气态汞和颗粒态汞)的干沉降速度较大(0.13、4.5和0.45 cm·s-1),水体表面上的相对较小(0.0012,0.5和0.11 cm·s-1)。敏感性分析发现,三类汞的干沉降速度随着近地层风速增加;降水或者地表湿度降低会导致零价汞和活性气态汞干沉降速度增加;雪盖厚度会减小气态零价汞的干沉降速度而增加活性气态汞的干沉降速度。三类汞的干沉降速度在区域上分布类似,东北以及南部地区最高,华东地区最小。季节变化上,气态零价汞、活性气态汞的干沉降速度在多数下垫面都夏季最大,冬季最小;颗粒态汞季节变化不明显。朱佳雷 王体健 王婷婷 Leiming Zhang Zhang 2014生态毒理学报2014,9,5:7
10GPS short-delay multipath estimation and mitigation based on least square method显示文摘The GPS multipath signal model is presented,which indicates that the coherent DLL outputs in multipath environment are the convolution between the ideal DLL outputs and the channel responses.So the channel responses can be estimated by a least square method using the observed curve of the DLL discriminator.In terms of the estimated multipath channels,two multipath mitigation methods are discussed,which are equalization filtering and multipath subtracting,respectively.It is shown,by computer simulation,that the least square method has a good performance in channels estimation and the multipath errors can be mitigated almost completely by either of the methods.However,the multipath subtracting method has relative small remnant errors than equalization filtering.Zhang Shengkang~(1,2),Wang Hongbo~(1,2),Yang Jun~(1,2) & He Leiming~(1,2) 1.Beijing Inst.of Radio Metrology and Measurement,Beijing 100854,P.R.China 2.National Key Laboratory of Metrology and Calibration Technology,Beijing 100854,P.R.China 2009Journal of Systems Engineering and Electronics2009,20,5:6
11一种电力电缆的随机电热退化模型(英文)显示文摘In this paper a methodology is proposed to model the stochastic electro-thermal degradation accumulation in cables.The cable life and the reliability are predicted by estimating the accumulated electro-thermal degradation during seasonal load cycles.The degradation is considered,in a novel approach,as stochastic in nature due to variations in the manufacturing process of insulation raw material and in operational and environmental conditions.The methodology is based on estimation of life by using combined electro-thermal life model,simulation of degradation accumulation process under electro-thermal stress in each season of the year based on Miner’s cumulative damage theory and reliability prediction from a probabilistic point of view.A case study is demonstrated on 10 k V XLPE cables which are directly buried in the UK and China.Results show that,the electro-thermal life of the cable is 56 and 69 years in China and the UK,respectively at 50%failure probability,or the life of the cable in the UK would be 13 years longer than in China,when other stresses such as mechanical and environmental are also considered and assumed to be the same.Swati Sachan Rui Wen Yong Xiang Leiming Yao Chengke Zhou 2015高电压技术2015,41,4:6
12Hic74,a novel alanine and glycine rich matrix protein related to nacreous layer formation in the mollusc Hyriopsis cumingii显示文摘Organic matrix proteins play an important role in the biomineralization of mollusc shells.We have identified and characterized a novel matrix protein,namely hic74,isolated from the mantle of the freshwater mussel Hyriopsis cumingii.The hic74 gene encodes a 850 amino acid protein that is rich in alanine(ala,30.8%),glycine(gly,25.8%)and serine(ser,10.6%),with ala mainly existing in poly-ala forms within the ala/gly-rich regions.Quantitative PCR expression analysis demonstrated that hic74 was specifically amplified from the mantle and in situ hybridization showed a strong signal in the epithelial cells in the pallial region of the mantle.Lower levels of expression were detected during the early stages of pearl sac formation but increased and remained constant during nacreous layer formation suggesting that hic74 might be involved in this process.Xiaojun Liu Can Jin Leiming Wu Shaojian Dong Shimei Zeng Jiale Li 2017Aquaculture and Fisheries2017,2,3:6
13Litter mixing significantly affects decomposition in the Hulun Buir meadow steppe of Inner Mongolia, China显示文摘Aims We explored the decomposition rates of single-and mixed-species litter,the litter-mixing effect and the effect of component litters in a mixture on decomposition.Methods In a litter bag experiment,shoot litters from two dominant grasses(Leymus chinensis and Stipa baicalensis)and one legume(Melissitus ruthenica)were decomposed separately and as a mixture from May 2010 to September 2011 in the Hulun Buir meadow steppe of Inner Mongolia,China.We separated the litter mixture into its individual component litters(i.e.the different single-species litters)and analyzed the changes in litter mass remaining and litter nitrogen(N)remaining during single-and mixed-species litter decomposition.Important Findings(i)Litter mixing had significant positive effects on litter decomposition.The litter-mixing effect was strongest for the mixture of S.baicalensis and L.chinensis litters,followed by the mixture of S.baicalensis and M.ruthenica litters.(ii)Single-species component litters decomposed faster in the mixtures than separately(positive effect),but these effects were not significant for legume species M.ruthenica litter.Relative to single-species litter decomposition,the decomposition rates of the two grass(S.baicalensis and L.chinensis)litters significantly increased when they were mixed with each other or with M.ruthenica litter.(iii)For each species litter type,the percentage of litter N remaining during decomposition(NR)differed between the single-species litter and mixed litter treatments.The NR of S.baicalensis litter was higher when it was decomposed in the mixture than in isolation.However,the NR of L.chinensis litter was lowest in its mixture with M.ruthenica among the treatments.Regardless of its decomposition in the mixture or in isolation,the NR of M.ruthenica litter varied little among treatments.There was a significant positive relationship between the NR and percentage of initial litter mass remaining in both the single litter and mixed litter treatments.These results suggest that N transfer may happen among component litters in mixture and further affect the decomposition.Caihong Zhang Shenggong Li Leiming Zhang Xiaoping Xin Xingren Liu 2014Journal of Plant Ecology2014,7,1:6
14Reaction kinetics of CaC2 formation from powder and compressed feeds显示文摘Renxing Wang Zhenyu Liu Leiming Ji Xiaojin Guo Xi Lin Junfei Wu Qingya Liu 2016Frontiers of Chemical Science and Engineering2016,10,4:6
15Mating patterns and pollen dispersal in a Japanese larch(Larix kaempferi) clonal seed orchard: a case study显示文摘Pollination dynamics highly determines the genetic quality of seed orchard crops. However, there is less research about the effect of mating patterns on seed productivity of orchard crops. So far, clonal seed orchards have been producing genetically improved seedlings used for most Japanese larch(Larix kaempferi(Lamb.) Carr.) plantations in China. In the present study, a total of 17 highly variable simple sequence repeat(SSR) markers were used for genotyping a progeny trial population consisting of 647 open-pollinated progenies germinated from seeds which were collected from 63 maternal clones with 140 potential paternal clones in a Japanese larch clonal seed orchard in China. Paternity analysis was used in the present case study in order to evaluate the level of paternal gametic contribution, estimate pollen contamination and selfing rates, and investigate pollination patterns,pollen dispersal patterns and the impact of mating patterns on seed productivity of orchard crops. We observed 93.7% of the success rate of the parental assignment, unequal paternal gametic contribution(0–12.4%) with 6.3% of the progenies derived from pollen contamination or unsampled pollen donors, and absence of evidence for selfing. We also found that pollination rate highly depended on the distance between pollen donors and maternal parents, the majority of the identified crossing(65.7%)occurred between clones within a 150-m radius, and large variations in growth performance existed among the paternal halfsiblings. Progeny growth performance(diameter at breast(DBH) and height(HGT)) was measured at Age-20 in order to investigate the impact of mating patterns on timber production of orchard crops. As either the paternal or maternal, two clones(i.e., clones Z38 and Z62) were identified to have produced progenies with higher average stem volume breeding values than that of all of the progenies. Specifically, the genetic gains for volume were 3.53% for the two clones as paternal parents, and 8.26% as the maternal parents at Age-20. Thus, both elite clones were ideal candidates for the construction of next-generation clonal seed orchards due to their synchronous reproductive phenology with greater crossing rate and higher genetic gain. These results improved the pedigree information to provide solid evidence of mating patterns for future design and effective management of seed orchards and for the development of viable long-term breeding strategies for other coniferous species.Xingbin Chen Xiaomei Sun Leiming Dong Shougong Zhang 2018Science China(Life Sciences)2018,61,9:5
16Expression of Wnt and NCX1 and its correlation with cardiomyocyte apoptosis in mouse with myocardial hypertrophy显示文摘Objective:To study the correlation between expression of Wnt and NCXl and cardiomyocyte apoptosis in mouse with myocardial hypertrophy.Methods:C57B/16 male mice were given the subcutaneous injection of 1 mg/kg isoprenaline to build the myocardial hypertrophy model.After 14 d of model building,mice were executed by cervical vertebra luxation.The ratio of heart weight/body weight(HW/BW) and heart weight/tibia length(HW/TL) was observed and proved using HE staining mat detected the size of eaidiomyocytes.40 male C57B/16 mice were randomly divided into the sham group(normal saline) and model group(isoprenaline),with 20 mice in each group.The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling was applied to detect the cardiomyocyte apoptosis;while Western blot and immunohistochemistry were employed to detect the expression of Wnt and NCX1.Meanwhile,the correlation between these two proteins and cardiomyocyte apoptosis was explored.Results:Compared with the sham group,the ratio of HW/BW and HW/TL was increased in the model group,as well as the bigger and hypertrophied cardiomyocytes,decreased number and increased apoptosis of eaidiomyocytes,and increased positive expression of Wnt3 a,WntSa and NCXl in the cardiac muscle tissue.Besides,there was positive correlation between the expression of Wnt and NCXl and the cardiomyocyte apoptosis.Conclusions:The expression of Wnt3 a,Wnt5a and NCXl in mouse with myocardial hypertrophy is increased and positively correlated with the cardiomyocyte apoptosis.Jing He Yi Cai Leiming Luo Rong Wang 2015Asian Pacific Journal of Tropical Medicine2015,8,11:5
17Simulated NH_4^+-N Deposition Inhibits CH_4 Uptake and Promotes N_2O Emission in the Meadow Steppe of Inner Mongolia, China显示文摘Few studies are conducted to quantify the effects of enhanced N deposition on soil nitrous oxide(N_2O) emission and methane(CH_4) uptake in the meadow steppe of Inner Mongolia, China. A two-year field experiment was conducted to assess the effects of nitrogen(N) deposition rates(0, 10, and 20 kg N ha^(-1)year^(-1) as(NH_4)2SO_4) on soil N_2O and CH_4 fluxes. The seasonal and diurnal variations of soil N_2O and CH_4 fluxes were determined using the static chamber-gas chromatography method during the two growing seasons of 2008 and 2009. Soil temperature, moisture and mineral N(NH_4^+-N and NO-3-N) concentration were simultaneously measured. Results showed that low level of(NH_4)2SO_4(10 kg N ha-1year-1) did not significantly affect soil CH_4 and N_2O fluxes and other variables. High level of(NH_4)_2SO_4(20 kg N ha^(-1)year) significantly increased soil NO-3-N concentration by 24.1% to35.6%, decreased soil CH_4 uptake by an average of 20.1%, and significantly promoted soil N_2O emission by an average of 98.2%.Soil N_2O emission responded more strongly to the added N compared to CH_4 uptake. However, soil CH_4 fluxes were mainly driven by soil moisture, followed by soil NO-3-N concentration. Soil N_2O fluxes were mainly driven by soil temperature, followed by soil moisture. Soil inorganic N availability was a key integrator of soil CH_4 uptake and N_2O emission. These results suggest that the changes of availability of inorganic N induced by the increased N deposition in soil may affect the CH_4 and N_2O fluxes in the cold semi-arid meadow steppe over the short term.LIU Xingren ZHANG Qingwen LI Shenggong ZHANG Leiming REN Jianqiang 2017Pedosphere2017,27,2:4
18Discovery of branched tubular algae and microscopic tubes with annular-helical thickening from the Mesoproterozoic Ruyang Group of Shanxi,North China显示文摘Most previously reported Mesoproterozoic (1600-1000 Ma) fossils are from silicified carbonates, and they are commonly small in size (15-20 μm, ranging from coccoids to fila- ments in morphology. Many of them can be interpreted as cyanobacteria. Carbonaceous shales represent another source of palaeontological information of the Mesoproterozoic biosphere. Sphaeromorphic and acanthomorphic acritarchs, as well as filamentous fossils, are common in many Mesoproterozoic shales. Here we report an unusual assemblage of tubular fossils from the Meosproterozoic Ruyang Group in Shanxi, North China. Some of these tubes are branched. Others bear annular-helical thickening that might be represented by one extinct algae to adapt to a desiccating environment.YIN Leiming BIAN Lizeng YUAN Xunlai 2004Science China Earth Sciences2004,47,10:4
19Comparison between cryptospores from the Cambrian Log Cabin Member,Pioche Shale,Nevada,USA and similar specimens from the Cambrian Kaili Formation,Guizhou,China显示文摘Abundant cryptospore-like microfossils have been collected from a sample of the'Middle'Cambrian Log Cabin Member of the Pioche Shale in eastern Nevada,USA.Compared with organic-walled microfossils obtained from the Cambrian Kaili Formation in eastern Guizhou Province,China,some specimens of leiosphers may be inferred to be similar cryptospore-like microfossils.The new fossil record would be the oldest known specimens of cryptospore-like microfossils during the Cambrian Period.YIN LeiMing ZHAO YuanLong BIAN LiZeng PENG Jin 2013Science China Earth Sciences2013,56,5:4
20Ultrasensitive biosensors based on long-range surface plasmon polariton and dielectric waveguide modes显示文摘An ultrasensitive biosensor based on hybrid structure and composed of long-range surface plasmon polariton(LRSPP) and dielectric planar waveguide(PWG) modes is proposed. Both PWG and LRSPP modes have strong resonances to form strong coupling between the two modes, and the two modes can couple to enhance sensitivity of sensors. In the hybrid structure, PWG is composed of cytop–Si–cytop multilayers and the LRSPP configuration is composed of cytop–metal–sensing medium multilayer slabs. The highest imaging sensitivities of 2264 and3619 RIU-1were realized in the proposed sensors based on Au and Al-monolayer graphene, respectively, which are nearly 1.2 and 1.9 times larger than the 1910 RIU-1sensitivity of the conventional LRSPR sensor(LRSPP sensor). Moreover, it is demonstrated that the PWG-coupled LRSPP biosensor is applicable to the sensing medium,with refractive index in the vicinity of 1.34.Leiming Wu Jun Guo Hailin Xu Xiaoyu Dai Yuanjiang Xiang 2016Photonics Research2016,4,6:4
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