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Assessment of Greenland surface melt algorithms based on DMSP and SMOS data

Advances in Polar Science 2023年第3期34卷 177-189页

作者： LI Qian WANG che ZHANG Tong cheNG wei DING Minghu State Key Laboratory of Urban Environmental Processes and Digital Simulation Capital Normal UniversityBeijing 100048China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Beijing Institute of Applied Meteorology Beijing 100029China

Satellite-borne microwave radiometers provide essential measurements to study the surface melt state of ice sheets. Therefore, selecting suitable microwave radiometer data is critical to characterize the spatial distribution of surface melt. In this study, we investigated the Greenland Ice Sheet and evaluated the usefulness, as climate indicators, of data acquired by microwave radiometers onboard the F17 satellite of the United States of America Defense Meteorological Satellite Program(DMSP) and the Soil Moisture and Ocean Salinity(SMOS) satellite of the European Space Agency. First, surface melt was simulated using the DMSP dataset as input for a brightness temperature threshold algorithm, the Microwave Emission Model of Layered Snowpacks(MEMLS2), and the SMOS dataset as input for the L-band Specific MEMLS(LS-MEMLS). For accuracy evaluation, the simulation results were then compared with surface melt estimates derived from air temperature measurements at Automatic Weather Stations and from ice surface temperature measurements from the Moderate Resolution Imaging Spectroradiometer(MODIS) satellite-borne instrument. Our results show that global(over Greenland) MEMLS2 simulation performance(overall accuracy 83%) was higher than that of LS-MEMLS(overall accuracy 78%). However, in southeastern Greenland, MEMLS2 omission error was markedly higher than that of LS-MEMLS, whereas LS-MEMLS could detect longer-lasting surface melt than MEMLS2. This analysis showed that DMSP-based surface melt simulations are more accurate than SMOS-based simulations, thereby providing a data selection reference for surface melt studies of the Greenland Ice Sheet.

关键词： Greenland Ice Sheet surface melt microwave radiometer MEMLS2 LS-MEMLS

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Investigation on plasma structure evolution and discharge characteristics of a single-stage planar-pulsed-inductive accelerator under ambient fill condition

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Chinese Physics B 2020年第11期29卷 398-405页

作者： Xiao-Kang Li Bi-Xuan che Mou-Sen cheng Da-wei Guo Mo-Ge Wang Yun-Tian yang College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

The physical process of a single-stage planar-pulsed-inductive accelerator is *** include the waveforms of circuit current,capacitor voltage,plasma radiation intensity,and temporal plasma structure photos captured by a high-speed *** are conducted under static ambient fill condition using argon as *** values of capacitor voltage and gas pressure are *** discussions quantify the EM interaction between circuit and plasma,as well as their energy deposition and current sheet *** on the results of experiments,physical mechanisms of the initial ionization phase and the following acceleration phase are analyzed theoretically.

关键词： electric propulsion pulsed-inductive thruster discharge characteristics plasma structure

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Engineering optimization approach of nonaqueous electrolyte for sodium ion battery with long cycle life and safety

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Green Energy & Environment 2021年第2期6卷 212-219页

作者： Haiying che Xinrong yang Yan Yu Chaoliang Pan hong Wang Yonghong Deng Linsen Li Zi-Feng Ma Shanghai Electrochemical Energy Devices Research Center Depurment of Chemical EngineeringShanghai Jiao Tong UniversitygShanghai200240China Zhejiang NaTRIUM Energy Co.Ltd. Shaoxing 312000China Shanghai Zjian chemical Technology Co.Ltd Shanghai200241China Shenzhen CAPcheM Technology Co.Ltd Shenzhen518027China

Electrolyte design strategies are closely related to the capacities, cycle life and safety of sodium–ion batteries. In this study, we aimed to optimize electrolyte with the focus on engineering aspects. The basic physicochemical properties including ionic conductivity, viscosity,wettability and thermochemical stability of the electrolytes using Na PF6 as the solute and the mixed solvent with different components of EMC,DMC or DEC in PC or EC were systematically measured. Ah pouch cell with NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)/hard carbon electrodes was used to evaluate the performance of the prepared electrolytes. By using the Inductive Coupled Plasma Emission Spectrometer(ICP), X-ray photoelectron spectroscopy(XPS), Thermogravimetric-differential scanning calorimetry(TG-DSC) and Accelerating Rate Calorimeter(ARC), we show that an optimized electrolyte can effectively promote the formation of a protective interfacial layer on two electrodes, which not only retards parasitic reactions between the electrodes and electrolyte but also suppresses dissolution of metal ions from the cathode. With an optimized electrolyte, a NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)/hard carbon cell can attain 56.16% capacity retention under the low temperature of -40℃, and can be able to retain 80%capacity retention after more than 2500 cycles while presenting excellent thermal safety.

关键词： Sodium–ion battery NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2) Nonaqueous electrolyte Safety Engineering optimization

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Heterogeneous sea-level rises along coastal zones and small islands

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Science Bulletin 2019年第11期64卷 748-755页

作者： Guoshuai Li Xin Li Tandong Yao Tao che hong yang Mingguo Ma Haipeng Zhao Xiaoduo Pan Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Dapartment of Geography and Environmental Science University of ReadingWhiteknightsReading RC6 6ABUK Research Base of Karst Eco-environments at Nanchuan in Chongqing Ministry of Natural ResourcesSchool of Geographical SciencesSouthwest UniversityChongqing 400715China Department of Earth and Environmental Systems Indiana State UniversityTerre HauteIN 47809USA

Coastal zones and many small islands are highly susceptible to sea-level rise(SLR). Coastal zones have a large exposed population and integrated high-value assets, and islands provide diverse ecosystem services to millions of people worldwide. The coastal zones and small islands affected by SLR are likely to suffer from submergence, flooding and erosion in the future. However, very few studies have addressed the heterogeneity in SLR changes and the potential risk to coastal zones and small islands. Here we used the mean sea level(MSL) derived from satellite altimetry data to analyse the trends and accelerations of SLRs along global coastal zones and small islands. We found that except for the Antarctic coastal zone, the annual MSL within 50 km of the coasts presented an increasing trend of 3.09 ± 0.13 mm a^-1 but a decreasing acceleration of -0.02 ± 0.02 mm a^-2 from 1993 to 2017. The highest coastal MSL trend of3.85 ± 0.60 mm a^-1 appeared in Oceania, and the lowest trend of 2.32 ± 0.37 mm a^-1 occured in North America. Africa, North America and South America showed acceleration trends, and Eurasia, Australia and Oceania had deceleration trends. Further, MSLs around global small islands reflected an increasing trend with a rate of 3.01 ± 0.16 mm a^-1 but a negative acceleration of -0.02 ± 0.02 mm a^-2. Regional heterogeneity in the trends and accelerations of MSLs along the coasts and small islands suggests that stakeholders should take discriminating precautions to cope with future disadvantageous impacts of the SLR.

关键词： Sea-level rise Coastal zones Small islands Heterogeneity

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UV/VUV switch-driven color-reversal effect for Tb-activated phosphors

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Light(Science & Applications) 2016年第1期5卷 842-847页

作者： Chun che Lin wei-Ting chen cheng-I Chu Kuan-wei Huang Chiao-Wen Yeh Bing-Ming cheng Ru-Shi Liu Department of chemistry Taiwan UniversityTaipei Synchrotron Radiation Research Hsinchu Department of Mechanical Engineering and Graduate Institute of Manufacturing Technology Taipei University of TechnologyTaipei

The remarkable narrow-band emission of trivalent lanthanide-doped phosphors excited by the vacuum ultraviolet(VUV)radiation lines of Xe atoms/Xe_(2) molecules at 147/172 nm are extensively investigated in the development of plasma display panels and Hg-free fluorescent lamps,which are frequently used in our daily *** solid materials,particularly Tb^(3+)-doped oxides,such as silicates,phosphates and borates,are efficient green/blue sources with color-tunable *** excitation wavelength and rare earth concentration are usually varied to optimize efficiency and the luminescent ***,some underlying mechanisms for the shift in the emission colors remain *** present study shows that a UV/VUV switch systematically controls the change in the phosphor(Ba_(3)Si_(6)O_(12)N_(2):Tb)photoluminescence from green to blue,resulting in a green emission when the system is excited with UV ***,a blue color is observed when the radiation wavelength shifts to the VUV ***,a configurational coordinate model is proposed for the color-reversal *** this model,the dominant radiative decay results in a green emission under low-energy UV excitation from the ^(5)D_(4) state of the f–f inner-shell transition in the Tb ***,under high-energy VUV excitation,the state switches into the ^(5)D_(3) state,which exhibits a blue *** mechanism is expected to be generally applicable to Tb-doped phosphors and useful in adjusting the optical properties against well-known cross-relaxation processes by varying the ratio of the green/blue contributions.

关键词： color-reversal cross-relaxation phosphor terbium UV/VUV

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Analysis of Nutrition of Total Mixed Ration for Dairy Cows on a Large-scale Ranch of Heilongjiang Reclamation Area

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Journal of Northeast Agricultural University(English Edition) 2022年第3期29卷 66-76页

作者： che Han-yang Liu Da-sen wei wei College of Animal Sciences and Technology Northeast Agricultural UniversityHarbin 150030China College of Science Northeast Agricultural UniversityHarbin 150030China

With the rapid development of China's dairy industry,the yield and scale of dairy cows have gradually increased,and the total mixed ration(TMR)technology has been widely applied in *** seven large-scale pastures in the Heilongjiang reclamation area were *** area was divided into high milk yield pastures(A,E,F and G)and low milk yield pastures(B,C and D).The nutritional contents of TMR of the seven pastures were compared with NRC(2001)*** results showed that in the high milk yield pastures,the crude protein(CP)contents were closer to NRC recommendations(2001)than those of the low milk yield pastures,and the contents of ether extract(EE)were significantly higher(P<0.05).The contents of acid detergent fiber(ADF)in TMR of all the scale pastures were close to those recommended by NRC(2001),where as the contents of neutral detergent fiber(NDF)were significantly higher than the NRC(2001)*** measuring the dry matter(DM)rumen degradation rates,CP,NDF and ADF of TMR of dairy cows on the ranch were assessed using the nylon bag method,CP contents of the high milk yield pastures were significantly higher(P<0.05)compared with those of the low milk yield pastures,and the rumen degradable protein(RDP)to rumen undegradable protein(RUP)ratio was more *** diets in the high milk yield pastures had significantly higher NDF contents and degradation rates than those in the low milk yield pastures,except pasture D(P<0.05).The diets in pastures E and G(with higher milk yields)had higher ADF degradation rates than pastures B,C and D,which had lower milk yields(P<0.05).Additionally,the type and digestibility of roughage were also related to dairy cows'*** summary,dairy cow performance was positively correlated with the nutrition of *** exploring the quality of TMR from the aspects of TMR's nutritional contents,rumen degradation rates and feed ingredients,this study provided a reference for the evaluation of TMR nutrition.

关键词： total mixed ration(TMR) rumen degradation nutrient level

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Corrosion assessment for spent nuclear fuel disposal in crystalline rock,using variant cases of hydrogeological modeling

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Nuclear Science and Techniques 2020年第12期31卷 20-31页

作者： Chi-che Hung Fraser King Yun-chen Yu Chi-Jen chen Yuan-Chieh Wu wei-Ting Lin 机构不详

This paper presents a corrosion assessment of copper spent nuclear fuel disposal canisters in crystalline rock,using hydrogeological modeling.A simplified approach is considered,to avoid complex and time-consuming computer *** simplified case is presented as a base case,with changes in the hydrogeological parameters presented as variant *** results show that in Taiwan’s base case,decreasing the hydraulic conductivity of the rock or decreasing the hydraulic conductivity of dikes results in a shorter transport path for sulfide and an increase in corrosion ***,the estimated canister failure time is still over one million years in the variant cases.

关键词： Spent nuclear fuel disposal Corrosion assessment Hydrogeological modeling

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Mg-doped CaCO_(3)nanoarchitectures assembled by(441)high-index facets for efficient trace removal of Pb(Ⅱ)

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Rare Metals 2023年第2期42卷 525-535页

作者： Yu Yan Yu-Bo Cui Qing-Yan Wang Zhong-Xuan che Tong Liu An-Ran Li wei Zhou School of chemistry Beijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing100191China

Removal of trace heavy metal ions puts high demands on designing adsorbents with favorable ***-plane engineering can provide controllable adsorption energy between surficial planes and ***,we have creatively synthesized Mg-doped CaCO_(3)nanoarchitectures assembled by layered sheets(Mg-CaCO_(3)LSs)with high-index facets of(441)through a facile wet chemical *** tests reveal that the layer-bylayer assembled sample exhibits a maximum Pb(II)adsorption capacity of 1961.9 mg·g^(-1),agreeing with the monolayer-adsorption Langmuir *** an initial Pb(II)ion concentration of 20 mg·L^(-1),the adsorption can achieve a high removal rate near 99.0%within 1 min,and the adsorption kinetics follows a chemisorption pseudo-second-order ***,the Mg-CaCO_(3)LSs show much-improved adsorption properties towards low-concentration Pb(II)ions,which could reduce the concentration from 1 mg·L^(-1)to~2.9μg·L^(-1)in 3 h(within 30 min decrease to less than 10μg·L^(-1),meeting drinking water standard from WHO).For comparison,the commercial CaCO_(3)and collected CaCO_(3)scale show much lower adsorption values with Pb(Ⅱ)ion residual concentration of~935.0 and~944.9μg·L^(-1)in 3 h,*** diffraction(XRD),energy dispersive spectroscopy(EDS),and inductively coupled plasma(ICP)characterizations on the Mg-CaCO_(3)LSs before and after adsorbing Pb(Ⅱ)confirm that the high removal performance could be ascribed to fast metal ion exchange and excellent physical adsorption contributed by high-index *** density functional theory(DFT)calculations also confirm that the much-enhanced adsorption kinetics benefits from the optimal adsorption of the(441)*** work will provide a feasible route to design highefficient low-cost adsorbents through crystal-plane engineering.

关键词： High-index plane Calcium carbonate High adsorption energy Trace Pb(Ⅱ)removal

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Risk of cholangiocarcinoma in patients undergoing therapeutic endoscopic retrograde cholangiopancre-atography or cholecystectomy: A population based study

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World Journal of Gastrointestinal Oncology 2019年第3期11卷 238-249页

作者： Chi-Chih Wang Ming-Chang Tsai Wen-wei Sung Tzu-wei yang Hsuan-Yi chen Yao-Tung Wang Chang-cheng Su Ming-Hseng Tseng Chun-che Lin Institute of Medicine Chung Shan Medical University School of Medicine Chung Shan Medical University Division of Gastroenterology and Hepatology Department of Internal Medicine Chung Shan Medical University Hospital Department of Urology Chung Shan Medical University Hospital Institute and Department of Biological Science and Technology National Chiao Tung University Division of Pulmonary Medicine Department of Internal Medicine Chung Shan Medical University Hospital Department of Medical Informatics Chung Shan Medical University Information Technology Office Chung Shan Medical University Hospital

BACKGROUND Cholangiocarcinoma is a highly lethal disease that had been underestimated in the past two decades. Many risk factors are well documented for in cholangiocarcinoma, but the impacts of advanced biliary interventions, like endoscopic sphincterotomy(ES), endoscopic papillary balloon dilatation(EPBD),and cholecystectomy, are inconsistent in the previous *** To clarify the risks of cholangiocarcinoma after ES/EPBD, cholecystectomy or no intervention for cholelithiasis using the National Health Insurance Research Database(NHIRD).METHODS From data of NHIRD 2004-2011 in Taiwan, we selected 7938 cholelithiasis cases as well as 23814 control group cases(matched by sex and age in a 1:3 ratio). We compared the previous risk factors of cholangiocarcinoma and cholangiocarcinoma rate in the cholelithiasis and control groups. The incidences of total and subsequent cholangiocarcinoma were calculated in ES/EPBD patients, cholecystectomy patients, cholelithiasis patients without intervention,and groups from the normal *** In total, 537 cases underwent ES/EPBD, 1743 cases underwent cholecystectomy,and 5658 cholelithiasis cases had no intervention. Eleven(2.05%), 37(0.65%), and7(0.40%) subsequent cholangiocarcinoma cases were diagnosed in the ES/EPBD,no intervention, and cholecystectomy groups, respectively, and the odds ratio for subsequent cholangiocarcinoma was 3.13 in the ES/EPBD group and 0.61 in the cholecystectomy group when compared with the no intervention *** In conclusion, symptomatic cholelithiasis patients who undergo cholecystectomy can reduce the incidence of subsequent cholangiocarcinoma, while cholelithiasis patients who undergo ES/EPBD are at a great risk of subsequent cholangiocarcinoma according to our findings.

关键词： Cholangiocarcinoma Endoscopic sphincterotomy Endoscopic papillary balloon dilatation Cholecystectomy

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The Contribution of Opal-Associated Phosphorus to Bioavailable Phosphorus in Surface and Core Sediments in the East China Sea

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Journal of Ocean University of China 2018年第3期17卷 571-580页

作者： LI Huanxin HE Huijun yang Shifeng LIU Yanli che hong LI Mujian ZHANG Jing Key Laboratory of Marine chemistry Theory and Technology Ministry of Education Ocean University of China Earth and Environmental System Graduate School of Science and Engineering University of Toyama

To improve the burial flux calculations of bioavailable phosphorus （P） and study opal-associated P （Opal-P） in the East China Sea （ECS）, surface and core sediments were collected in the Changjiang Estuary （CE） and the south of the cheju Island. In this study, sedimentary P was operationally divided into seven different forms using modified sedimentary extraction （SEDEX） technique： LSor-P （exchangeable or loosely sorbed P）, Fe-P （easily reducible or reactive ferric Fe-bound P）, CFA-P （authigenic carbonate fluorapatite and biogenic apatite and CaCO3-bound P）, Detr-P （detrital apatite）, Org-P （organic P）, Opal-P and Ref-P （refractory P）. The data revealed that the concentrations of the seven different P forms rank as Detr-P 〉 CFA-P 〉 Org-P 〉 Ref-P 〉 Opal-P 〉 Fe-P 〉 LSor-P in surface sediments and CFA-P 〉 Detr-P 〉 Org-P 〉 Ref-P 〉 Fe-P 〉 Opal-P 〉 LSor-P in core sediments. The distributions of the total phosphorus （TP）, TIP, CFA-P, Detr-P are similar and decrease from the CE to the south of the cheju Island. Meanwhile, Org-P and Opal-P exhibit different distribution trends; this may be affected by the grain size and TOM. The concentrations of potentially bioavailable P are 9.6-13.0 μmol g^-1 and 10.0-13.6 μmol g^-1, representing 61%-70% and 41%？64% of the TP in surface and core sediments, respectively. The concentrations of Opal-P are 0.6-2.3 μmol g^-1 and 0.6-1.4 μmol g^-1 in surface and core sediments, ac-counting for 5.3%？19.8% and 4.2%？10.6% of bioavailable P, respectively. The total burial fluxes of Opal-P and bioavailable P are 1.4×10^9 mol y^-1 and 1.1×10^10 mol yr^-1 in the ECS, respectively. Opal-P represents about 12.7% of potentially bioavailable P, which should be recognized when studying P cycling in marine ecosystems.

关键词： phosphorus speciation opal-associated P burial flux sediments East China Sea

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