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Rare Metals 2022年第7期41卷 2517-2526页

作者： lin Gao Lu-Lu Zhang xue-lin Yang College of Electrical Engineering&New Energy Hubei Collaborative Innovation Center for Microgrid of New EnergyThree Gorges UniversityYichang 443002China

The practical applications of carbon anode for lithium-ion batteries(LIBs)are largely obstructed by their moderate rate capability and cyclic ***,we report a N,S-codoped porous carbon nanosheet(NSC)decorated with Fe_(3)C nanoparticles(Fe_(3)C/NSC)by a one-pot pyrolysis *** high surface area and abundant defects of NSC can not only promote electrons and ions transfer,but also induce high pseudocapacitive *** importantly,the synergistic catalysis effect of Fe-Nx and Fe_(3)C can catalyze the reversible conversion of some solid electrolyte interface(SEI)components to offer excess capacity during *** expected,the Fe_(3)C-NSC anode delivers a discharge capacity of750 mAh·g^(-1)under a current density of 0.5 A·g^(-1)through 500 cycles and retains a dis-charge capacity of 366 mAh·g^(-1)at 4 A·g^(-1)after 1600 cycles,*** importantly,the lithium-ion capacitors based on Fe_(3)C/NSC anode demonstrate a high energy density of 249.5 Wh·kg^(-1)at 560 W·kg^(-1).

关键词： Fe_(3)C/NSC Lithium-ion batteries Pseudocapacitive behavior Lithium-ion capacitors

Research on assessment method of intrasystem and intersystem of the global navigation satellite system

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Science China(Technological Sciences) 2015年第10期58卷 1672-1681页

作者： ZHANG JianJun xue ming XIE Jun China Academy of Space Technology Qian xuesen Laboratory of Space Technology

The global navigation satellite system(GNSS) has become an important space infrastructure. Following GPS and GLONASS, Europe and China have been building their own global navigation satellite system, respectively, GALILEO and Compass. In order to consolidate the leadership of GPS in the globe, United States is gradually upgrading the traditional GPS. Simultaneously, Russia is also intensively restoring full performance of GLONASS. With the advancement of international satellite navigation system, satellite navigation frequency resources are already in short supply, and the design and use of the navigation signals are more sophisticated and complex due to commercial, disaster relief and other reasons. Since there may be many navigation signals in the same basic bandwidth, the coexistence of multiple systems and the combined application make intersystem mutual interference become the focus research. Under this background, the satellite navigation system mutual interference evaluation system needs to be established urgently to meet and support the compatibility and interoperability of the GNSS system. In the paper, through the performance analysis of the GNSS signal acquisition, carrier tracking, data demodulation and code tracking, the equivalent carrier to noise ratio model based on spectrum isolation coefficient is established, and the theoretical system of the GNSS signal mutual interference is proposed according to the mechanism, and the mutual interference of GPS, GALILEO and Compass system is analyzed and assessed.

关键词： GNSS intrasystem interference intersystem interference equivalent carrier to noise ratio

Influence of gut bacteria on type 2 diabetes:Mechanisms and therapeutic strategy

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World Journal of Diabetes 2025年第1期16卷 27-33页

作者： xue Wen Lu-ming Qi Kui Zhao College of Health and Rehabilitation Chengdu University of Traditional Chinese MedicineChengdu 610000Sichuan ProvinceChina College of Materials and Chemical Engineering Southwest Forestry UniversityKunming 650224Yunnan ProvinceChina

The onset and progression of type 2 diabetes mellitus(T2DM)are strongly associated with imbalances in gut bacteria,making the gut microbiome a new potential therapeutic *** commentary examines the recent publication in World Journal of *** article explores the association between T2DM and gut microbiota,with a focus on the pathophysiological changes related to *** proposes innovative microbiome-targeted therapeutic strategies and evaluates the challenges and future directions of such *** editorial summarizes the key points of their discussion of the role of the gut microbiome in T2DM and elaborates on the influence of specific gut microbial species on the disease through the host–microbiota metabolic *** provides new insights for future research on gut-microbiota-based interventions for T2DM.

关键词： Type 2 diabetes Intestinal microbiome Intestinal axis Biological pathways Treatment Short-chain fatty acids

The Impact of Satellite Radiance Data Assimilation within a Frequently Updated Regional Forecast System Using a GSI-based Ensemble Kalman Filter

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Advances in Atmospheric Sciences 2019年第12期36卷 1308-1326页

作者： Kefeng ZHU ming xue Yujie PAN ming HU Stanley G. BENJAMIN Stephen S. WEYGANDT Haidao lin Key Laboratory of Mesoscale Severe Weather/Ministry of Education and School of Atmospheric Sciences Nanjing UniversityNanjing 210023China Center for Analysis and Prediction of Storms University of OklahomaNorman Oklahoma 73072USA Nanjing University of Information Science and Technology Nanjing 210094China NOAA Earth System Research Laboratory BoulderCO 80305USA Cooperative Institute for Research in Environmental Sciences University of Colorado BoulderCO 80309USA

A regional ensemble Kalman filter (EnKF) data assimilation (DA) and forecast system was recently established based on the Gridpoint Statistical Interpolation (GSI) analysis system. The EnKF DA system was tested with continuous threehourly updated cycles followed by 18-h deterministic forecasts from every three-hourly ensemble mean analysis. Initial tests showed negative to neutral impacts of assimilating satellite radiance data due to the improper bias correction procedure. In this study, two bias correction schemes within the established EnKF DA system are investigated and the impact of assimilating additional polar-orbiting satellite radiance is also investigated. Two group experiments are conducted. The purpose of the first group is to evaluate the bias correction procedure. Two online bias correction methods based on GSI 3DVar and EnKF algorithms are used to assimilate AMSU-A radiance data. Results show that both variational and EnKF-based bias correction procedures effectively reduce the observation and background radiance differences, achieving positive impacts on forecasts. With proper bias correction, we assimilate full radiance observations including AMSU-A, AMSU-B, AIRS, HIRS3/4, and MHS in the second group. The relative percentage improvements (RPIs) for all forecast variables compared to those without radiance data assimilation are mostly positive, with the RPI of upper-air relative humidity being the largest. Additionally, precipitation forecasts on a downscaled 13-km grid from 40-km EnKF analyses are also improved by radiance assimilation for almost all forecast hours.

关键词： satellite radiance assimilation EnKF bias correction

Effect of six-stitch pancreaticojejunostomy on pancreatic fistula:A propensity score-matched comparative cohort study

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Hepatobiliary & Pancreatic Diseases International 2020年第3期19卷 277-283页

作者： Zhao-lin Zeng Yan Sun Da xue Pi-Li Liu Wang-ming Chen Lei Zhang Department of General Surgery the Second Affiliated Hospital of Harbin Medical UniversityHarbin 150086China

Background:Clinically relevant postoperative pancreatic fistula(CR-POPF)is the most common and severe complication after pancreaticoduodenectomy(PD).Despite the development of numerous anastomotic surgical techniques to minimize CR-POPF,more than 30%of patients who undergo PD develop ***,we propose a novel pancreaticojejunostomy(PJ)technique and evaluate its efficacy and safety compared to traditional ***:This retrospective study enrolled 164 consecutive patients who underwent PJ after PD between January 2012 and June *** them,78(47.6%)underwent traditional PJ and 86(52.4%)underwent sixstitch *** primary outcome was CR-POPF at 1-month follow-up defined according to the revised 2016 International Study Group on Pancreatic Fistula *** adjust for baseline differences and selection bias,patients were matched by propensity scores,which left 63 patients with traditional PJ and 63 with six-stitch ***:Compared to patients who underwent traditional PJ(mean age 56.2±9.4 years),patients who underwent six-stitch PJ(mean age 57.4±11.4 years)had a lower CR-POPF *** risk of CR-POPF among patients who underwent six-stitch PJ was decreased by 81.7%after adjustment for age,sex,body mass index,and disease severity compared to patients who underwent traditional ***,the surgery time was reduced from 29 min for traditional PJ to 15 min for six-stitch PJ(P<0.001).Adverse effects such as abdominal fluid collection,abdominal bleeding,and wound infection were similar between two ***:Six-stitch PJ may be an effective and efficient PJ technique for patients who undergo PD surgery.

关键词： Duct-to-mucosa Pancreaticoduodenectomy Pancreaticojejunostomy Clinically relevant postoperative pancreatic fistula

Performance analysis of 3G systems in presence of UWB interference

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The Journal of China Universities of Posts and Telecommunications 2011年第2期18卷 120-124页

作者： SUN xue-bin GAO ming-liang ZHOU Zheng ZHAO Cheng-lin LIU Wei School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China China Mobile Research Institute (China) Beijing 100053 China

In this paper,the impact of the interference from multiple ultra wideband（UWB） transmitters to a 3rd-generation（3G） terminal is evaluated under UWB emission power limit regulations of federal communications commission（FCC）,european telecommunications standards institute（ETSI） and Japan respectively.A three-dimensional interference model is presented where a discrete spatial distribution of UWB transmitters is *** is assumed that a mobile terminal and a large number of UWB devices exist in one room simultaneously.A parameter which characterizes the link budget degradation at the victim receiver is defined to measure the UWB interference to 3G *** maximum acceptable density of UWB transmitters and the minimum acceptable distance between UWB transmitters and the 3G terminal are analyzed under different link budget *** simulation results demonstrate that the performance of time division-synchronous code division multiple access（TD-SCDMA） is the best,the one of code division multiple access 2000（CDMA2000） is the worst and the one of wideband code division multiple access（WCDMA） lies between them in presence of UWB interference.

关键词： UWB TD-SCDMA CDMA2000 WCDMA interference

Substituent Effect on Infrared Spectra and Thermodynamic Properties of Polynitroamino Substituted Cyclopentane and Cyclohexane

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Chinese Journal of Chemical Physics 2008年第6期21卷 526-534页

作者： ling Qiu xue-dong Gong He-ming Xiao Institute for Computation in Molecular and Material Science School of Chemical Engineering Nanfing University of Science and Technology Nanjing 210094 China Key Laboratory of Nuclear Medicine Ministry of Health Jiangsu Institute of Nuclear Medicine Wuxi 214063 China

Density functional theory method was employed to study the effect of the nitroamino group as a substituent in cyclopentane and cyclohexane, which usually construct polycyclic or caged nitramines. Based on the optimized molecular structures of two groups of monocyclic nitramines at the B3LYP/6-31G^＊＊ level, the infrared （IR） spectra were obtained and assigned by harmonic vibrational analysis. The calculated results agree reasonably with the available experimental data. According to the principles of statistic thermodynamics, thermodynamic properties were derived from the IR spectra, which were linearly correlated with the number of nitroamino groups as well as the temperature. The contributions of nitroamino groups to thermodynamic properties are in accord with the group additivity.

关键词： Density functional theory Substituent effect Monocyclic nitramine Infrared spectrum Thermodynamic property

A Study on a Snowband Associated with a Coastal Front and Cold-Air Damming Event of 3-4 February 1998 along the Eastern Coast of the Korean Peninsula

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Advances in Atmospheric Sciences 2013年第2期30卷 263-279页

作者： Jae-Gyoo LEE ming xue Department of Atmospheric Environmental Sciences Kangnung National University Center for Analysis and Prediction of Storms Norman OKUSA School of Meteorology University of OklahomaNorman OKUSA

A 24-h simulation with the Advanced Regional Prediction System （ARPS） nonhydrostatic model is performed for the heavy snowfall event of 3-4 February 1998 along the eastern coast of Korean Peninsula; the results are used to understand the snowfall process, including why the precipitation maxima formed along the Yeongdong coastal region rather than over the mountain slope and ridge top during. The numerical simulation with a 4-kin horizontal grid spacing and 43 levels reproduces very well the narrow snowband located off the eastern Korean coast, away from, instead of over, the Yeongdong coastal mountain range. The general evolution of the snowband agrees quite well with radar observations, while the water-equivalent precipitation amount agrees reasonably well with radar precipitation estimate. The simulation results clearly show that the snow band developed due to the lifting by a coastal front that developed because of the damming of cold air against the eastern slope of the coastal mountain range. The damming was enhanced by the advection of cold air by a tow-level mountain-parallel jet from the north, formed due to geostrophic adjustment as the on-shore upslope air was decelerated by the mountain blocking. As the onshore flow weakened later due to synoptic-scale flow pattern change, the cold front propagated off shore and the precipitation dissipated.

关键词： coastal snowfall cold air damming orographic precipitation

The Vignetting Effect of a LAMOST-Type Schmidt Telescope

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Chinese Journal of Astronomy and Astrophysics 2008年第5期8卷 580-590页

作者： Yuan xue Huo-ming Shi National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Optical vignetting of a Schmidt reflector is caused mainly by the spherical primary mirror not being big enough and by the effective light-collecting area of the corrector, which depends on the direction of the star light. Calculations of the vignetting of LAMOST, a special reflecting Schmidt telescope, are made by ray-tracing methods. The results show various features due to LAMOST＇s structure and observing modes. The un-vignetted field is small compared with its field of view. In the outmost portions of the field vignetting in- creases rapidly with the distance to the field center. The vignetting at a general position within the field of view is a function of both its distance to the field center and its position angle. Vignetting varies when the telescope points at different declinations and during observations. There is difference in vignetting between direct imaging and multi-fiber spectroscopy. Vignetting distorts the relative intensity of celestial objects at different positions in a field and also affects accurate sky-estimation and sky-subtraction. The determined vignetting functions may be used to correct the vignetting effect; alternatively flat-fielding may be adopted for the calibration. The effective apertures, which affect the signal-to-noise ratio of the observations, depend on the different declinations the telescope is pointing at and also different positions within a field due to vignetting.

关键词： telescope - methods miscellaneous

Global Analysis of Expression Profiles of Rice Receptor-Like Kinase Genes

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Molecular Plant 2012年第1期5卷 143-153页

作者： lin-lin Gao Hong-Wei xue National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and EcologyShanghai Institutes for Biological Science(SIBS)ChineseAcademy of Sciences300 Fenglin Road20032 ShanghaiChina

The receptor-like kinases （RLKs） play critical roles in plant development and response to stress stimuli. By perceiving or sensing the extracellular signals, RLK activates the downstream signaling pathway through phosphorylating the specific targets. Up to now, only a few RLKs have been functionally identified, which are even fewer in rice （Oryza sativa L.）. We here report the systemic analysis of the expression profiles of rice RLK coding genes in different tissues, with the emphasis on seed development and in response to both abiotic stress and plant hormones. The results showed that most rice RLK genes are expressed in two or more tissues, of which the RLCK-RLKs have a higher, while WAK- and SD-RLKs have a lower, expression level in the vegetative tissues than other subfamily members. Interestingly, the constitutively highly expressed RLKs in rice and Arabidopsis are conserved, which is consistent with the previous hypothesis that RLKs existed before the differentiation of monocotyledon and dicotyledon plants. Nearly one-third of the detected rice RLKs are expressed during seed development, and the RLCK-RLK members possess a higher percentage during the endosperm de- velopment, suggesting a novel function of RLCK-RLK members in endosperm development. Further analysis revealed that many RLK genes expressed during seed development are also regulated by abiotic stresses （cold, salt, or drought） or hor- mones, indicating that RLKs may take part in the stress-related signaling pathways such as dehydration of endosperm. These results provide informative insights into the RLK studies and will be helpful to reveal the global regulatory network controlling rice seed development.

关键词： Receptor-like kinase rice profiling seed development stress ABA.