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Evaluation of surface temperature and pressure derived from MERRA-2 and ERA5 reanalysis datasets and their applications in hourly GNSS precipitable water vapor retrieval over China

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Geodesy and Geodynamics 2023年第2期14卷 111-120页

作者： Liangke Huang Xiaoyang Fang Tengxu Zhang Haoyu Wang Lei Cui Lilong Liu college of Geomatics and Geoinformation Guilin University of TechnologyGuilin 541006China School of resources and Environmental science and Engineering Hubei University of Science and TechnologyXianning 437100China

Temperature and pressure play key roles in Global Navigation Satellite System(GNSS) precipitable water vapor(PWV) retrieval. The National Aeronautics and Space Administration(NASA) and European Center for Medium-Range Weather Forecasts(ECMWF) have released their latest reanalysis product: the modern-era retrospective analysis for research and applications, version 2(MERRA-2) and the fifthgeneration ECMWF reanalysis(ERA5), respectively. Based on the reanalysis data, we evaluate and analyze the accuracy of the surface temperature and pressure products in China using the the measured temperature and pressure data from 609 ground meteorological stations in 2017 as reference values.Then the accuracy of the two datasets and their performances in estimating GNSS PWV are analyzed. The PWV derived from the pressure and temperature products of ERA5 and MERRA-2 has high accuracy. The annual average biases of pressure and temperature for ERA5 are-0.07 hPa and 0.45 K, with the root mean square error(RMSE) of 0.95 hPa and 2.04 K, respectively. The annual average biases of pressure and temperature for MERRA-2 are-0.01 hPa and 0.38 K, with the RMSE of 1.08 h Pa and 2.66 K, respectively.The accuracy of ERA5 is slightly higher than that of MERRA-2. The two reanalysis data show negative biases in most regions of China, with the highest to lowest accuracy in the following order: the south,north, northwest, and Tibet Plateau. Comparing the GNSS PWV calculated using MERRA-2(GNSS MERRA-2 PWV) and ERA5(GNSS ERA5 PWV) with the radiosonde-derived PWV from 48 co-located GNSS stations and the measured PWV of the co-location radiosonde stations, it is found that the accuracy of GNSS ERA5 PWV is better than that of GNSS MERRA-2 PWV. These results show the different applicability of surface temperature and pressure products from MERRA-2 and ERA5 data, indicating that both have important applications in meteorological research and GNSS water vapor monitoring in China.

关键词： Temperature and pressure Global navigation satellite system Precipitable water vapor MERRA-2 ERA5

Effects of hydrothermal carbonization temperature on carbon retention,stability,and properties of animal manure-derived hydrochar

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International Journal of Agricultural and Biological Engineering 2022年第1期15卷 124-131页

作者： Feiyue Li Zelun Jiang Wenchao Ji Yihan Chen Jiran Ma Xiangyang Gui Jianrong Zhao Chunhuo Zhou college of resources and Environment science Anhui Science and Technology UniversityFengyang 233100AnhuiChina School of resources and Environmental Engineering Hefei University of TechnologyHefei 230009China college of Land resources and Environment Jiangxi Agricultural UniversityNanchang 330045China

Hydrothermal carbonization of animal manure is being increasingly recognized as a green process for hydrochar production.Temperature obviously affects the properties of hydrochar especially with respect to carbon retention and stability.These properties determine the carbon sequestration potential of hydrochar but related researches are limited.In this study,chicken,dairy,and swine manures were collected and hydrothermal carbonized under different temperature conditions,aiming to study the fuel characteristics,carbon retention,and stability of hydrochar influenced by temperature.Results show that high temperature led to low yield and declined H/C,O/C,and volatile matter of hydrochar.While high temperature caused high fixed carbon,fuel ratio,and heating value of hydrochar,indicating that animal manure hydrochar can be adopted as an alternative of fuel.After hydrothermal carbonization,less than half of carbon from animal manure was retained in hydrochar:22.70%-46.71%for chicken manure,39.36%-49.72%for dairy manure,and 36.24%-64.21%for swine manure.The carbon retention decreased with the increase of temperature.Conversely,high temperature improved the aromatic and strengthened the resistance to thermal oxidation of hydrochar,which was evidenced by FTIR and TGA analysis.Moreover,the carbon sequestration capacity of animal manure hydrochar was less than a third of total carbon(originated from animal manure)and relatively low temperature(no more than 250℃)was beneficial to produce hydrochar for carbon sequestration.

关键词： livestock manure carbon sequestration hydrochar hydrothermal temperature

Characteristics of sea ice kinematics from the marginal ice zone to the packed ice zone observed by buoys deployed during the 9th Chinese Arctic Expedition

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Acta Oceanologica Sinica 2022年第7期41卷 113-127页

作者： Xiaomin Chang Longchun Ye Guangyu Zuo Jingyue Li Keyu Wei Yinke Dou college of Water resources science and Engineering Taiyuan University of TechnologyTaiyuan030024China college of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan030024China

Sea ice growth and consolidation play a significant role in heat and momentum exchange between the atmosphere and the ocean.However,few in situ observations of sea ice kinematics have been reported owing to difficulties of deployment of buoys in the marginal ice zone(MIZ).To investigate the characteristics of sea ice kinematics from MIZ to packed ice zone(PIZ),eight drifting buoys designed by Taiyuan University of technology were deployed in the open water at the ice edge of the Canadian Basin.Sea ice near the buoy constantly increased as the buoy drifted,and the kinematics of the buoy changed as the buoy was frozen into the ice.This process can be determined using sea ice concentration,sea skin temperature,and drift speed of buoy together.Sea ice concentration data showed that buoys entered the PIZ in mid-October as the ice grew and consolidated around the buoys,with high amplitude,high frequency buoy motions almost ceasing.Our results confirmed that good correlation coefficient in monthly scale between buoy drift and the wind only happened in the ice zone.The correlation coefficient between buoys and wind was below 0.3 while the buoys were in open water.As buoys entered the ice zone,the buoy speed was normally distributed at wind speeds above 6 m/s.The buoy drifted mainly to the right of the wind within 45°at wind speeds above 8 m/s.During further consolidation of the ice in MIZ,the direct forcing on the ice through winds will be lessened.The correlation coefficient value increased to 0.9 in November,and gradually decreased to 0.7 in April.

关键词： sea ice kinematics buoy observations remote sensing marginal ice zone

Zircon SHRIMP U–Pb geochronology,geochemistry,and geological significance of dacite in the Zhesang gold district,southeast Yunnan Province,China

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Acta Geochimica 2023年第2期42卷 290-308页

作者： Bo Wang Jiasheng Wang Jinlong Li Hao Fu Yuehua Ma Bin Ye Earth science Department of Land resources college Kunming University of Science and TechnologyKunming 650093China Yunnan Bureau of Coalfield Geology Kunming 650034China

The Late Paleozoic and Mesozoic tectonic framework of the Nanpanjiang Basin has much been disputed.Herein,the middle-acid volcanic rock,dacite,exposed to the Zhesang gold district,southeast Yunnan Province,has been analyzed.The results show that the dacite belongs to a calc-alkaline series,SiO_(2)contents range from 62.79 to 76.66 wt%.Zircon SHRIMP U–Pb dating of dacite demonstrates that they were formed in the Early Triassic(247.8±1.7 Ma,MSWD=1.2).All samples exhibit enrichment in LILE(e.g.Rb,K,Th,and U),and depletion in HFSE(e.g.Nb,Ta,and Ti),which has the geochemical affinity of I-type granite.La–La/Sm and La–La/Yb discrimination diagrams show that the partial melting,mainly of the mafic lower crust,of rocks,plays a major role in the formation process.The dacite has low initial ^(87)Sr/^(86)Sr ratios(0.706954 to 0.708589)and negative ε_(Nd)(t)values(-11.77 to-10.88).Zircons in dacite have ε_(Hf)(t)values of-16.2 to-8.3,and the two-stage Hf model ages are 1799–2301 Ma,mostly concentrated between 1800 and 1900 Ma,indicating that the magma source area is the reconstructed ancient lower crust mixed with some mantle materials,and crystal fractionation process underwent in the late stage of magma migration.This study reveals that the arc-volcanic rocks of the Early Triassic in the southern margin of the Nanpanjiang Basin were formed by the subduction of the Late Paleozoic ocean basin within the border region between China and Vietnam.

关键词： Dacite Zircon SHRIMP U–Pb geochronology Sr–Nd–Hf isotope Geochemistry Arcvolcanic rock Late Paleozoic ocean basin

Seasonal dependency of controlling factors on the phytoplankton production in Taihu Lake, China

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Journal of Environmental sciences 2019年第2期31卷 278-288页

作者： Qiaohua Zhao Jing Wang Jianjian Wang Julian X.L.Wang college of Hydrometeorology Nanjing University of Information Science and Technology Air resources Laboratory National Oceanic and Atmospheric AdministrationCollege Park

In this study, 44 profiles of gross primary productivity(GPP) and sunlight, along with water temperature, Chlorophyll-a(Chla) and nutrients, were observed in Meiliang Bay of Taihu Lake, China, in the spring, summer, and fall seasons. Effects of water temperature, light,and nutrient concentration were examined in relation to the GPP-unit-Chla(GPP of algae per Chla). The results showed that the optimum temperature for the GPP of phytoplankton was 27.9°C, the optimal PNA-unit-Chla(photon number absorbed by phytoplankton per Chla) was 0.25(mol), and the HSCN-unit-Chla and HSCP-unit-Chla(half-saturation constants of nitrogen and phosphorus of algae per Chla) were 0.005(mg/L) and 0.0004(mg/L), respectively. The seasonal dependency of the effect of different factors on the GPP was analyzed. Compared with temperature and nutrients, light was found to be the most important factor affecting the GPP during the three seasons. The effect of temperature and nutrients on the GPP of phytoplankton has obvious seasonal change. In spring, temperature was the secondary factor affecting the GPP of phytoplankton, and the effect of nutrients may be negligible in the eutrophic lake on account of temperature limit, which showed that the GPP of algae was only affected by the physical process. In summer and fall, temperature didn't affect the GPP of algae, and the presence of nutrients was the secondary factor affecting the GPP of phytoplankton. From summer to fall, effect of phosphorus was weakened and effect of nitrogen was enhanced.

关键词： Temperature limited effect Gross primary productivity Eutrophication Light limit Optimum temperature Half-saturation constants

Response mechanism of Chlamydomonas reinhardtii to nanoscale bismuth oxyiodide(nano-BiOI):Integrating analysis of mineral nutrient metabolism and metabolomics

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Journal of Environmental sciences 2022年第11期34卷 13-24页

作者： Yan Huang Jinlong Lai Yang Huang Xuegang Luo Xu Yang Zewei Liu Yue Duan Chen Li School of Life sciences Southwest University of Science and TechnologyMianyang 621010China college of Environment and resources Southwest University of Science and TechnologyMianyang 621010China Laboratory of Solid Waste Treatment and Resource Recycle Ministry of EducationMianyang 621010China college of Chemical and Environment science Shaanxi University of TechnologyHanzhong 723000China

Nanoscale bismuth oxyiodide(nano-BiOI) is widely studied and applied in environmental applications and biomedical fields, with the consequence that it may be deposited into aquatic environments. However, the impact of nano-Bi OI on aquatic ecosystems, especially freshwater microalga, remains limited. Herein, the nano-Bi OI was synthesized and its response mechanism towards microalga Chlamydomonas reinhardtii was evaluated. Results showed that a low concentration of nano-Bi OI(5 mg/L) could stimulate algal growth at the early stage of stress. With the increase in concentration, the growth rate of algal cells was inhibited and showed a dose effect. Intracellular reactive oxygen species(ROS) were significantly induced and accompanied by enhanced lipid peroxidation, decreased nonspecific esterase activity, and significantly upregulated glutathione S-transferase activity(GST) activity. Mineral nutrient metabolism analysis showed that nano-Bi OI significantly interfered with the mineral nutrients of the algae. Non-targeted metabolomics identified 35 different metabolites(DEMs, 22 upregulated, and 13 downregulated) under 100 mg/L Bi OI stress.Metabolic pathway analysis demonstrated that a high concentration of nano-Bi OI significantly induced metabolic pathways related to amino acid biosynthesis, lipid biosynthesis,and glutathione biosynthesis, and significantly inhibited the sterol biosynthesis pathway.This finding will contribute to understanding the toxicological mechanisms of nano-Bi OI on C. reinhardtii.

关键词： Chlamydomonas reinhardtii Nano-BiOI Mineral nutrient Metabolomics

Mining the key regulatory genes of chicken inosine 5'-monophosphate metabolism based on time series microarray data

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Journal of Animal science and Biotechnology 2015年第3期6卷 280-290页

作者： Teng Ma Lu Xu Hongzhi Wang Jing Chen Lu Liu Guobin Chang Guohong Chen Animal Genetic resources Laboratory College of Animal Science and TechnologyYangzhou University

IMP （inosine 5＇-monophosphate） is a compound that enhances the flavor of poultry meat. IMP has become a new breeding trait to improve poultry meat quality. We tried to identify several potential regulatory genes, and construct their predicted regulatory relationships. Time series gene expression profiles of thigh muscle tissues of Rugao chicken, a famous indigenous breed in China, were performed for analysis of genes that are co-expressed or correlated with the concentration of IMP. We found 15 crucial co-expression genes, which are Hspa2, Pten, Gabpa, Bpi, Mkll, Srf,, Cd34, Hspa4, EtvS, Bmpr2, Gdel, IgfbpS, Cd28, Pecam1 and Gja1, that may directly or indirectly regulate IMP metabolism. Eventually, we computed the correlation coefficient between 19 IMP Genes and 15 CGs （15 co-expression genes）, and we identified and constructed a predicted regulation network. In conclusion, variation of IMP concentration was primarily connected with the muscle development process. During this process, 15 CGs were identified that may have significant influence on IMP metabolism. In particular, Bmpr2, Pten and co-expression genes correlated with Entpd8 might play important roles in regulating IMP de novo synthesis, decomposition and salvage synthesis.

关键词： Co-expression Hub genes IMP metabolism Regulation network

Mechanisms of aid-leaching reagent calcium fluoride in the extracting vanadium processes from stone coal

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Rare Metals 2013年第1期32卷 57-62页

作者： Fei Wang Yi-Min Zhang Jing Huang Tao Liu Yi Wang Xiao Yang Jie Zhao college of resources and Environmental Engineering Wuhan University of Science and Technology

The mechanisms of aid-leaching reagent calcium fluoride in the extracting vanadium processes were researched by comparing the blank extraction with the extraction with calcium fluoride as aid-leaching reagent. The leaching experiments were carried out under the conditions of 95 ~C, 6 h, 1.5 ml.g-1, 15 vol % H2SO4, and 5 % calcium fluoride （mass ratio of CaF2 to stone coal）. The concentrations of hydrogen ion were adjusted from initial 1.82 and 4.79 mol.L-1 to the pH of 1.80 4- 0.05 by 200 g.L-1 lime milk, respectively. The solvent extraction experiments were carded out under the organic phase using 15 vol% D2EHPA, 5 vol% TBP, and 80 vol% sulfonated kerosene and O/A phase ratio of 1/4. The leaching rate of vanadium and six-stage countercurrent solvent extraction rate of vanadium can be remarkably improved from 66.71 to 92.97 % and 81.15 to 98.81%, respectively, when calcium fluoride was added as aid-leaching reagent. In the leaching process, fluorine can enhance the breakage of the structure of vanadium-bearing minerals. Meanwhile, fluoride ion can combine with iron ion to generate acid-insoluble iron fluoride hydrate （Fe2Fs.7H20） and consume all ferric ions and a portion of ferrous ions. In adjusting pH value process, the massive impurities are decreased to form KA1SO4 and FeA1Fs. In solvent extraction process, fluorine can prevent the formation of ferric hydroxide colloids and eliminate the formed unstable ferric hydroxide colloids and the silicon-containing colloids to promote the sufficient contact between the aqueous phase and the organic phase and the sufficient reaction.

关键词： Vanadium Stone coal Aid-leaching reagent Calcium fluoride Mechanisms

Application of Hausdorff fractal derivative to the determination of the vertical sediment concentration distribution

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International Journal of Sediment Research 2023年第1期38卷 12-23页

作者： Hongguang Sun Shiqian Nie Aaron I.Packman Yong Zhang Dong Chen Chengpeng Lu Chunmiao Zheng State Key Laboratory of Hydrology-Water resources and Hydraulic Engineering Hohai University college of Mechanics and Materials Hohai University college of Mathematics and Systems science Shandong University of Science and Technology Department of Civil and Environmental Engineering Northwestern University Department of Geological sciences University of Alabama Institute of Geographic sciences and Natural resources Research Chinese Academy of sciences college of Hydrology and Water resources Hohai University School of Environmental science and Engineering Southern University of Science and Technology

The Rouse formula and its variants have been widely used to calculate the steady-state vertical concentration distribution for suspended sediment in steady sediment-laden flows, where the diffusive flux is assumed to be Fickian. Turbulent flow, however, exhibits fractal properties, leading to non-Fickian diffusive flux for sediment particles. To characterize non-Fickian dynamics of suspended sediment, the current study proposes a Hausdorff fractal derivative based advection-dispersion equation(HADE)model, where the Fickian diffusive flux in the Rouse model is replaced by a fractal derivative re-scaled using a constant diffusivity. The order of the Hausdorff fractal derivative is designed to characterize the influence of the multi-fractal turbulence structure on sediment diffusion. Applications show that the HADE model, with the analytical solution expressed using a stretched exponential function, can accurately describe the observed vertical concentration profiles for suspended sediment with different sizes.This improvement well captures the non-exponential decay of the vertical sediment concentration in turbulent flow. Further analyses of measured sediment concentration profiles reveal that the Hausdorff fractal order decreases with the Rouse parameter, which describes the stronger impact of turbulent flow and a more uniform sediment concentration profile for smaller particles. Model comparisons also show that the HADE model provides better performance in describing the sediment concentration profiles than the improved Rouse formula and the standard fractional derivative advection-dispersion equation(FADE), which either under-or over-estimates vertical displacement of sediment particles, likely due to coherent turbulent structures.

关键词： Anomalous diffusion Hausdorff fractal derivative Vertical concentration distribution Suspended sediment Metric transform