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In situ xRD and electrochemical investigation on a new intercalation-type anode for high-rate lithium ion capacitor

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journal of Energy Chemistry 2021年第6期30卷 109-117,I0004页

作者： Bobo Zou Ting Wang Shengyuan Li Rong kang Guochun Li Sherif AEl-Khodary Dickon HLng xianhu Liu j.ngxia Qiu Yan Zhao jiabiao Lian Huaming Li Institute for Energy Research Jiangsu UniversityZhenjiang 212013JiangsuChina Nanyang Environment and Water Research Institute(NEWRI) Interdisciplinary Graduate School(IGS)Nanyang Technological University50 Nanyang Avenue639798Singapore Department of Physics The Chinese University of Hong KongShatinHong KongChina Key Laboratory of Materials Processing&Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002HenanChina

A new intercalation-type anode material is reported herein to improve the lithium storage kinetics for high-rate lithium ion *** crystal structure of orthorhombic NaNbO3 indicates two possible tunnels for lithium ions insertion into NaNbO3 host along theand***,in situ xRD is conducted to investigate the lithium storage mechanism and structural evolution of the NaNb O_(3) anode,demonstrating its intercalation behavior through(101)and(141)***,the rGO nanosheets are introduced to facilitate the charge transfer,which also effectively prevent the aggregation of NaNbO3 *** expected,the NaNbO_(3)/rGO nanocomposites possess remarkable reversible capacity(465 mA h g^(-1) at 0.1 A g^(-1)),superior rate capability(325 mA h g^(-1) at 1.0 A g^(-1))and cycling stability,attributed to their synergistic effect and high Li+diffusion coefficient DLi[D(NaNbO_(3)/rGO)/D(NaNbO_(3))≈31.54].Remarkably,the NaNbO3/rGO-based LIC delivers a high energy density of 166.7 W h kg^(-1) at 112.4 W kg^(-1) and remains 24.1 W h kg^(-1) at an ultrahigh power density of26621.2 W kg^(-1),with an outstanding cycling durability(90%retention over 3000 cycles at 1.0 A g^(-1)).This study provides new insights on novel intercalation-type anode material to enrich the materials system of LICs.

关键词： Lithium ion capacitor Intercalation-type anode NaNbO3 nanocubes In situ xRD High energy/power densities

Upgradation of Heavy Crude Oil Via Hydrodynamic Cavitation Through Variations in Asphaltenes

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China Petroleum Processing & Petrochemical Technology 2022年第2期24卷 23-33页

作者： Li kang Han Haibo Lei jie Wang Youhe Li Dekun Mark j.Rood Fazle Subhan Yan Zifeng State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao 266580China Luoyang R&D Center of Technology of Sinopec Engineering(Group)Co.Ltd. Luoyang 471003China Shandong Oil Refining Association Jinan 250013China Department of Civil and Environmental Engineering University of IllinoisIL 61801USA Department of Chemistry Abdul Wali Khan University MardanMardanKPPakistan

In this work,Saudi heavy crude oil(SHCO)was upgraded by the hydrodynamic cavitation *** collapse of cavitation bubbles instantly produces extreme conditions such as high temperature,pressure,and jet flow and strong shear forces,which can play a significant role in the upgradation *** results revealed that the viscosity and Conradson carbon residue of SHCO decreased from 13.61 to 7.22 mm^(2)/s and from 7.16%to 6.48%,*** boiling point distillation findings showed that the vacuum residue(VR)decreased by 1%.Atmospheric-pressure photoionization Fourier-transform ion cyclotron resonance mass spectrometry,x-ray diffraction,dynamic light scattering,Fourier-transform infrared spectroscopy,and scanning electron microscopy were employed to characterize the molecular composition,crystalline structure,asphaltene aggregate particle size distribution,functional groups,and morphology,respectively,to understand the effects of hydrodynamic cavitation on *** obtained results demonstrate that hydrodynamic cavitation upgradation reduced the interaction forces between the asphaltene molecules,weakening the crystalline structure of the asphaltene aggregates,reducing the degree of association of the aromatic compounds in SHCO and asphaltenes,and decreasing the average particle *** delayed coking properties of the VR were further investigated,and the cavitation treatment was found to decrease the coke yield by 1.85%and increase the liquid and gas yields by 1.52%and 0.33%,***,hydrodynamic cavitation can effectively enhance the processing performance of crude oil by improving the properties and structural characteristics of asphaltenes.

关键词： hydrodynamic cavitation heavy oil upgradation asphaltene crystalline structure particle size distribution agglomeration force

A study on low emittance injector and undulator for PAL-xFEL

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High Power Laser Science and Engineering 2015年第3期3卷 41-49页

作者： j.Hong j.-H.Han S.j.Park Y.G.j.ng D.E.Kim H.-S.kang j.Pflueger Pohang Accelerator Laboratory European xFEL

For the success of PAL-xFEL, two critical systems, namely a low emittance injector and a variable gap out-vacuum undulator, are under development. In order to realize the target emittance of the PAL-xFEL injector we carried out an optimization study of various parameters, such as the laser beam transverse profile, the laser pulse length, the laser phase,and the gun energy. The transverse emittance measured at the Injector Test Facility(ITF) is εx=0.48±0.01 mm *** undulator prototype based on the EU-xFEL design and modified for PAL-xFEL was built and tested. A local-K pole tuning procedure was developed and tested. A significant reduction(90%) of the local-K fluctuation was observed. The requirement of undulator field reproducibility better than 2×10-4and the undulator gap setting accuracy below 1 μm were achieved for the prototype. The optical phase jitter after the pole height tuning at the tuning gap was calculated to be 2.6? rms, which satisfies the requirement of 5.0?.

关键词： emittance free-electron lasers(FELs) photocathode RF-gun undulator

Significant influence of doping effect on photovoltaic performance of efficient fullerene-free polymer solar cells

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journal of Energy Chemistry 2020年第4期29卷 40-46页

作者： Qian kang Qi Wang Cunbin An Chang He Bowei xu jianhui Hou State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

The modification mechanism of the water/alcohol cathode interlayer is one of the most complicated problems in the field of organic photovoltaics,which has not been clearly elucidated yet;this greatly restricts the further enhancement of the PCE for polymer solar ***,we clarified the different effects of PFN and its derivatives,namely,poly[(9,9-bis(3’-((N,N-dimethyl)-N-ethylammonium)-propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)](PFN-Br) in modifying fullerene-free *** is found for the first time that doping on IT-4F by the amino group of PFN leads to the unfavorable charge accumulation,and hence,forms a dense layer of electronegative molecule due to the poor electron transport capacity of the non-fullerene acceptor *** electronegative molecular layer can block the electron transfer from the active layer to the interlayer and cause serious charge recombination at the active layer/cathode *** mechanism could be verified by the ESR measurement and electron-only *** replacing PFN with PFN-Br,the excessive doping effect between the cathode interlayer and IT-4F is eliminated,by which the charge transport and collection can be greatly *** a result,a high PCE of 13.5%was achieved in the fullerene-free PSCs.

关键词： Cathode interlayer Doping effect Electron transport Power conversion efficiency Electron-only device

Estimating canopy closure density and above-ground tree biomass using partial least square methods in Chinese boreal forests

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journal of Forestry Research 2012年第2期23卷 191-196页

作者： LEI Cheng-liang jU Cun-yong CAI Ti-jiu j.ng xia WEI xiao-hua DI xue-ying School of Forestry Northeast Forestry UniversityHarbin 150040P.R.China College of Geomatics Xi'an University of Science and TechnologyXi'an 710054P.R.China Department of Earth and Environmental Science University of BritishColumbia(Okanagan)3333 University wayKelownaBritish Colum-biaCanadaV1V 1V7.

Boreal forests play an important role in global environment systems. Understanding boreal forest ecosystem structure and function requires accurate monitoring and estimating of forest canopy and biomass. We used partial least square regression （PLSR） models to relate forest parameters, i.e. canopy closure density and above ground tree biomass, to Landsat ETM＋ data. The established models were optimized according to the variable importance for projection （VIP） criterion and the bootstrap method, and their performance was compared using several statistical indices. All variables selected by the VIP criterion passed the bootstrap test （p〈0.05）. The simplified models without insignificant variables （VIP 〈1） performed as well as the full model but with less computation time. The relative root mean square error （RMSE%） was 29% for canopy closure density, and 58% for above ground tree biomass. We conclude that PLSR can be an effective method for estimating canopy closure density and above ground biomass.

关键词： above-ground tree biomass bootstrap method canopy clo- sure density partial least square regression (PLSR) VIP criterion

Petrography and chronology of lunar meteorite Northwest Africa 6950

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Science China(Information Sciences) 2020年第4期63卷 182-194页

作者： Zemin BAO Yuruo SHI j.Lawford ANDERSON Allen KENNEDY Zuokai KE xiangping GU Peizhi WAng xiaochao CHE Yuelan kang Huiyi SUN Chen WAng Beij.ng SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences john de Laeter Centre Curtin University Department of Earth and Environment Boston University School of Geosciences and Infophysics Central South University

Northwest Africa(NWA) 6950 is an olivine-gabbro lunar meteorite that has a distinctly different petrographic texture from other lunar basalts. In this contribution, we report the petrography, mineralogy,and U-Pb geochronology of baddeleyite and phosphate in this lunar meteorite and make a comparison with other NWA 773 paired meteorites. NWA 6950 consists mainly of coarse-grained olivine, pyroxene,and plagioclase, with minor ilmenite, chromite, troilite, baddeleyite, taenite, and apatite. The abundant rounded to euhedral olivine has a limited Fo ranging from 68 to 69. Pyroxenes include both augite and pigeonite, with a narrow range of Mg#=71–80, and composition, respectively, EnFsWoand EnFsWo. Plagioclase is mainly anhedral, conforming to the crystal margins of olivine and pyroxene. The plagioclase grains are elongated and several hundreds of microns in length. Raman spectra shows that plagioclase has been transformed into maskelynite, which is very calcic(An87-95) with low sodium and very low potassium(Ab4-9 Or 0.6-3.7). The weighted mean207 Pb/206 Pb ages of baddeleyite and phosphate measured using a sensitive high resolution ion micro probe(SHRIMP II) are 3119 ± 16 Ma(n = 9, MSWD= 2.5)(mean squared weighted deviates, MSWD) and 3119 ± 18 Ma(n = 15, MSWD = 2.1), respectively,giving the crystallization age of the meteorite. NWA 6950 has similar mineral compositions, geochemical characteristics, and an almost identical age of crystallization to the magnesian gabbro of the NWA 773 *** conclude that NWA 6950 and NWA 773 are paired meteorites, which crystallize at ca. 3119 Ma, and represent magmatic activities in the KREEP(potassium(K), rare earth elements(REE) and phosphorus(P) rich lunar material) region of the Moon.

关键词： Northwest Africa 6950 lunar meteorite U-Pb chronology baddeleyite phosphate

Do microRNA 96, 145 and 221 expressions really aid in Lhe prognosis of prostate carcinoma？

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Asian journal of Andrology 2012年第5期14卷 752-757页

作者： Sung Gu kang Young Ran Ha Seo jin Kim Seok Ho kang Hong Seok Park jeong Gu Lee jun Cheon Department of Urology Korea University College of Medicine Seou1136-705 Republic of Korea and 2Department of Pathology Korea University College of Medicine Seoul 136 705 Republic of Korea Department of Pathology Korea University College of Medicine Seoul 136705 Republic of Korea

MicroRNAs （miRs） are small noncoding RNAs that have been reported to be premising diagnostic tools. We used quantitative real-time reverse transcription PCR （RT-qPCR） to analyze differentially expressed miRNAs in prostate tumor samples to determine its prognostic value. From 2007 to 2009, tumor tissues were obtained from 73 radical prostatectomy specimens. Differentially expressed miR-96, -145 and -221 were validated by TaqMan RT-qPCR using all 73 tissues. The prognostic value was assessed in terms of biochemical recurrence using Kaplan-Meier and Cox regression analyses. For our patient cohort, the mean age was 64.7 years （50-76 years） and the mean prostate-specific antigen （PSA） was 7.5 ng m1-1. During the follow-up period （mean, 19.4 months）, 14 of 73 （19.2%） patients developed biochemical recurrence. Expression of miR-96, -145 and -221 correlated strongly with each other, but there were no correlations between miRNA expression and clinicopathologic parameters. Kaplan-Meier survival curves using the log-rank test showed a decreased biochemical recurrence-free interval with pathologic stage （P〈O.O01）. In addition, patients with Gleason scores over 8, compared with those with a Gleason score of 6, showed a decreased biochemical recurrence-free interval in Kaplan-Meier analysis （P=O.O01）. However, expression of miR-96, -145 and -221 did not correlate with the biochemical recurrence interval in Kaplan-Meier survival curves or by multivariate analysis using the Cox proportional hazard regression model, either. In conclusion, we did not observe a significant correlation between the expression of miR-96, -145 and -221 and clinicopathologic parameters. To utilize miRNA as a diagnostic tool in clinical practice, more research is needed to understand miRNA mechanisms, identify miRNA targets, and further characterize miRNA function.

关键词： microRNA prognosis prostate cancer recurrence

The predictability of T3 disease in staging MRI following prostate biopsy decreases in patients with high initial PSA and Gleason score

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Asian journal of Andrology 2011年第3期13卷 487-493,515页

作者： Young Hwii Ko Deuk jae Sung Sung Gu kang Seok Ho kang jeong Gu Lee je j.ng Kim jun Cheon Department of Urology Korea University School of Medicine Seoul Korea Department of Radiology Korea University School of Medicine Seoul Korea

To obtain improved accuracy in predicting extracapsular extension （ECE） and seminal vesicle invasion （SVI）, we evaluated the variables affecting the predictability of staging magnetic resonance imaging （MRI, phased-array coil） and estimated their impact on accuracy between preoperative MRI staging and histological outcome. A total of 121 patients with localized or locally advanced prostate cancer who underwent robotic radical prostatectomy （RALP） were included. Following transrectal biopsy, all enrolled patients had undergone MRI for staging work-up. After RALP, only 43.8% （53/121） of the patients were matched with the MRI predicted stage. Compared to the matched group in the prediction of ECE, the unmatched group had significantly higher initial prostate-specific antigen （PSA, 12.8 ng m1-1 versus 8.1 ng m1-1, P=0.048）. In the prediction of SVI, initial PSA （8.1 ng ml- 1 versus 17.3 ng ml- 1, P=0.009） and biopsy Gleason score （6.5 versus 7.6, P=0.035） were significantly higher in the unmatched group. When applying clinical cutoffs of initial PSA of 10 and 20 ng ml-1, the accuracy of MRI in the prediction of ECE was decreased in the group with PSA over 20 ng ml- 1 （75.6, 64.5 and 37.5%, P=0.01）, and this group had significantly decreased accuracy of MRI in the prediction of SVI （91.5, 77.4 and 37.5%, P〈0.01）. Applying the clinical cutoff of a Gleason score of 7, the accuracy of MRI in the prediction of SVI was decreased in the higher G leason score group （93.9, 82.1 and 62.9%, P= 0.01）. Thus, for these patient groups, to obtain margin negativity during radical prostatectomy, operative findings, rather than post-biopsy MRI images, may provide substantial information, implying a clinical advantage in conducting MRI before prostate biopsy.

关键词： magnetic resonance imaging neoplasm staging prostatic neoplasms

Homogenous charge distribution by free-standing porous structure for dendrite-free Li metal anode

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journal of Energy Chemistry 2020年第5期29卷 68-72页

作者： Danmiao kang Kun Tang joonho Koh Wenbin Liang john PLemmon Present address:Shangshang Road 87.Liyang JiangsuChina.a National Institute of Clean-and-Low-Carbon EnergyFuture Science&Technology CityChangping DistrictBeijing 102209China NICE America Research 2091 Stierlin CtMountain ViewCA 94043United States

Lithium metal has a high theoretical capacity of 3860 mAh g^-1 and a low electrochemical potential(-3.04 V vs.H2/H^+).Hence,using a lithium anode significantly improves the energy density of a secondary ***,the lithium dendrites generated on the lithium anode during the platingdissolution process significantly reduce its cycling life and ***,we provide a simple method for lithium anode protection,by applying a free-standing porous carbon film with a high specific surface area to reduce the local current density and obtain a homogenous ion *** protected lithium anode has a long cycle life over 1000 h when cycled at 3 mA cm^-2 with a lithium capacity of 2.5 mAh cm^-***,the deposited lithium has a smoother surface than Li anode without carbon *** study will promote the wide application of Li-metal-based batteries with high safety levels.

关键词： Li-metal Carbon interlayer Dendrite Charge distribution