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Science China Earth Sciences 2017年第10期60卷 1854-1865页

作者： JIN ChenXi ZHOU TianJun CHEN XiaoLong wu bo LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Beijing Meteorological Service Center Beijing 100089 China University of Chinese Academy of Sciences Beijing 100049 China

We applied a season-reliant empirical orthogonal function(S-EOF) analysis based on the results of the Community Earth System Model, version 1-Biogeochemistry, to seasonal mean air-sea CO_2 flux over the western North Pacific(WNP)(0°–35°N, 110°E–150°E). The first leading mode accounts for 29% of the total interannual variance, corresponding to the evolution of the El Ni-Southern Oscillation(ENSO) from its developing to decaying phases. During the ENSO developing phase in the summer and fall, the contribution of surface seawater CO_2 partial pressure anomalies is greater than that of gas transfer/solubility anomalies, which contribute to increasing oceanic CO_2 uptake over the WNP. During the ENSO mature phase in the winter, the anomalous southwesterly northwest of the western North Pacific anticyclone(WNPAC) reduces the surface wind speed in the China marginal sea and thus decreases oceanic CO_2 uptake by reducing the gas transfer coefficient. In the subsequent spring, the WNPAC maintains with an eastward shift in position. The anomalous southwesterly warms sea surface temperatures in the China marginal sea by reducing evaporation and thus decreases oceanic CO_2 uptake by enhancing surface seawater CO_2 partial pressure. This process, rather than the effect of decreasing gas transfer coefficient, dominates CO_2 flux anomalies in the spring.

关键词： Air-sea CO2 flux Western North Pacific Interannual variability ENSO

Photo-assisted Cl doping of SnO_(2) electron transport layer for hysteresis-less perovskite solar cells with enhanced efficiency

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Rare Metals 2022年第2期41卷 361-367页

作者： Jin-bo wu Chao Zhen Gang Liu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Developing efficient electron transport layers(ETLs)along with proper interface engineering is crucial to achieve high-performance perovskite solar cells(PSCs).Herein,a photo-assisted doping strategy was developed to modify SnO_(2)ETLs with Cl^(-)for efficient *** Cl^(-)modified SnO2(Cl^(-)SnO_(2))with passivated surface defects as ETL material favors the formation of high phase-purity perovskite films and promotes the electron collection across the SnO_(2)/perovskite ***,the efficiency of PSC is improved from 16.35%without Cl modification to 18.94%with the Cl modification,with little hysteresis and high stability.

关键词： stability perovskite transport

Construction of One-Gray Weight Codes and Two-Gray Weight Codes over Z4+uZ4

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Journal of Systems Science & Complexity 2016年第5期29卷 1472-1484页

作者： SHI Minjia WANG Dandan GAO Jian wu bo Key Laboratory of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei 230039 China National Mobile Communications Research Laboratory Southeast University Nanjing 210096China School of Mathematical Sciences Anhui University Hefei 230601 China. School of Science Shandong University of Technology Zibo 255091 China State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences Bcijing 100093 China

This paper firstly gives some necessary conditions on one-Gray weight linear codes. And then we use these results to construct several classes of one-Gray weight linear codes over Z_4 +uZ_4(u^2=u) with type 16^(k_1)8^(k_2)8^(k_3)4^(k_4)4^(k_5)4^(k_6)2^(k_7)2^(k_8) based on a distance-preserving Gray map from(Z4 + u Z4)n to Z2n4. Secondly, the authors use the similar approach to do works on two-Gray(projective) weight linear codes. Finally, some examples are given to illustrate the construction methods.

关键词： Generator matrix Gray map linear code one-Gray weight code two-Gray weight code

Developing stages and causes of desertification in the Mu Us sandland

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Chinese Science Bulletin 1999年第9期44卷 845-849页

作者： bo wu Longjun Ci Chinese Acad Forestry Chinese Res & Dev Ctr Combating Desertificat Beijing 100091 Peoples R China

Based on historical aerial photography of three periods and together with field investigation, the status of desertification development after the 1950s in the Mu Us sandland was analyzed, the difference of the desertification developing speed at two stages was compared, and its possible causes were explored. The results show that the developing speed of desertification from the late 1970s to the early 1990s is apparently slowed down, compared with that from the late 1950s to the late 1970s and there exists an obvious recovery trend at the second stage. The difference between the two stages accounts for severely over-reclaiming, over-grazing and unrestricted cutting during the first stage, which are the main causes of desertification development in the semi-arid steppe and arid desert steppe areas.

关键词： Mu Us sandland desertification developing stage over-reclaiming over-grazing unrestricted cutting.

Experimental and CFD investigations of choked cavitation characteristics of the gap flow in the valve lintel of navigation locks

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Journal of Hydrodynamics 2020年第5期32卷 997-1008页

作者： bo wu Ya-an Hu Xin Wang Xiu-jun Yan Key Laboratory of Transport Technology in Navigation Building Construction Nanjing Hydraulic Research InstituteNanjing 210029China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210029China School of Water Resources and Hydropower Engineering Wuhan UniversityWuhan 430072China

The cavitation is ubiquitous in the water delivery system of high hydraulic head navigation *** paper studies the choked cavitation characteristics of the gap flows in the valve lintel of the navigation locks and analyzes the critical self-aeration *** cavitation gap flow in the valve lintel is experimentally and numerically investigated.A visualized 1:1 full-scale slicing model is designed,with a high-speed camera,the details of the cavitation flow is captured without the reduced scale ***,the numerical simulations are conducted to reveal the flow structures in the *** experimental results show that the flow pattern of the gap flow in the valve lintel could be separated into four models,namely,the incipient(1)the developing,(2),the intensive,(3),and the choked(4)cavitation *** numerical simulation results are consistent with the experimental *** choked cavitation conditions are crucial to the gap flow in the valve *** the choked cavitation occurs,the gap is entirely occupied by two cavitation cloud *** gap pressure then decreases sharply to the saturated water vapor pressure at the operating *** water vapor pressure is the ultimate negative pressure in the gap that remains unchanged with the continuous decrease of the downstream *** volumetric flow rate reaches a peak,then remains constant,with the further decrease of the pressure ratio or the cavitation *** the choking point,the volumetric flow rate is proportional to the root mean square of the difference between the upstream pressure(absolute pressure)and the saturated pressure of the ***,the pressure ratio is linearly correlated with the downstream cavitation number with a slope of(1+ζc).

关键词： Cavitation cavitation control by aeration self-aerated flows critical self-aerated conditions choked cavitation

Bis‐Lactam Peptide [i, i + 4]‐Stapling

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Chinese Journal of Chemistry 2019年第3期37卷 244-248页

作者： Xiao Hu bo wu Weiping Zheng School of Pharmacy Jiangsu University301 Xuefu RoadZhenjiangJiangsu 212013China

Summary of main observation and conclusion Even though the bis‐lactam peptide stapling with the [i, i + 7] and the [i, i + 11] systems has been known to be able to afford %α‐helicity values up to 100%(25°C), the performance of the bis‐lactam peptide stapling with the [i, i + 4] system in current literature has been mediocre (%α‐helicity ≦40%, 25℃). In the current study, we found that high %α‐helicity is also obtainable with the bis‐lactam [i, i + 4]‐stapling by demonstrating with our model peptide sequence that the bis‐lactam [i, i + 4]‐stapling with Nε‐para‐phenylenediacetyl‐lysine was able to afford a %α‐helicity value of ~64.1%(25℃). Therefore, the bis‐lactam [i, i + 4]‐stapling could also be an efficacious peptide stapling mode that can be employed for biomedical applications.

关键词： Bis bis has be our was can

Stability Criteria of Nonlinear Impulsive Differential Equations with Infinite Delays

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Acta Mathematicae Applicatae Sinica 2015年第4期31卷 921-934页

作者： Yang LIU bo wu Xiu-shan CAI Department of Mathematics Southeast University College of Mathematics Physics and Information EngineeringZhejiang Normal UniversityJinhua 321004China Graduate School Zhejiang Normal University

In this paper, we consider the uniform stability and uniformly asymptotical stability of nonlinear impulsive infinite delay differential equations. Instead of putting all components of the state variable x in one Lyapunov function, several Lyapunov-Razumikhin functions of partial components of the state variable x are used so that the conditions ensuring that stability are simpler and less restrictive; moreover, examples are discussed to illustrate the advantage of the results obtained.

关键词： uniformly asymptotical stability impulsive differential equation infinite delay

Seasonal Prediction of the Record-Breaking Northward Shift of the Western Pacific Subtropical High in July 2021

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Advances in Atmospheric Sciences 2023年第3期40卷 410-427页

作者： Shuai HU Tianjun ZHOU bo wu Xiaolong CHEN State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of the Chinese Academy of Sciences Beijing 100049China

The unprecedented Zhengzhou heavy rainfall in July 2021 occurred under the background of a northward shift of the western Pacific subtropical high(WPSH).Although the occurrence of this extreme event could not be captured by seasonal predictions,a skillful prediction of the WPSH variation might have warned us of the increased probability of extreme weather events in Central and Northern ***,the mechanism for the WPSH variation in July 2021 and its seasonal predictability are still ***,the observed northward shift of the WPSH in July 2021 is shown to correspond to a meridional dipole pattern of the 850-hPa geopotential height to the east of China,the amplitude of which became the strongest since *** meridional dipole pattern is two nodes of the Pacific–Japan *** investigate the predictability of the WPSH variation,a 21-member ensemble of seasonal predictions initiated from the end of June 2021 was *** predictable and unpredictable components of the meridional dipole pattern were identified from the ensemble *** predictable component is driven by positive precipitation anomalies over the tropical western *** positive precipitation anomalies are caused by positive horizonal advection of the mean moist enthalpy by southwesterly anomalies to the northwestern flank of anticyclonic anomalies excited by the existing La Niña,which is skillfully predicted by the *** leading mode of the unpredictable component is associated with the atmospheric internal intraseasonal oscillations,which are not initialized in the *** relative contributions of the predictable and unpredictable components to the observed northward shift of the WPSH at 850 hPa are 28.0%and 72.0%,respectively.

关键词： western pacific subtropical high seasonal prediction seasonal predictability La Niña Pacific-Japan pattern

Morphological characteristics and dynamic changes of seif dunes in the eastern margin of the Kumtagh Desert,China

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Journal of Arid Land 2020年第5期12卷 887-902页

作者： PANG Yingjun wu bo LI Yonghua XIE Shengbo Institute of Desertification Studies Chinese Academy of ForestryBeijing 100091China Key Laboratory of Desert Ecosystem and Global Change State Administration of Forestry and GrasslandBeijing 100091China Kumtagh Desert Ecosystem Research Station State Administration of Forestry and GrasslandDunhuang 736200China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The seif dune field over the gravel desert surface in the eastern margin of the Kumtagh Desert is a valuable experimental site for the observation of dune formation and *** used high-resolution remote sensing and station observation approaches,combined with wind and grain size data,to study the characteristics of the aeolian environment and the morphologies of and dynamic changes in seif *** observed the ratio of the resultant drift potential(RDP)to the drift potential(DP),which was 0.37,associated with an obtuse bimodal wind *** drift potentials in the west-northwest(WNW)and east-northeast(ENE)directions were dominant,and the angle between the two primary DP directions was 135.00°.The dune orientations ranged from 168.75°-213.75°,which were parallel to the resultant drift direction(186.15°).The dune lengths ranged from 51.68 to 1932.1 m with a mean value of 344.91 *** spacings of the dunes ranged from 32.34 to 319.77 m with a mean value of 93.39 *** mean grain size of the sediments became finer,and the sorting became better from upwind tail to downwind tip,which indicated that the sediment of the seif dunes in the study region may be transported from northward to *** rate of increase in the length,the mean longitudinal migration rate of the dune tail,and the mean longitudinal extension rate of the dune tip(also called elongation rate)were 4.93,4.63,and 9.55 m/a,*** mean lateral migration vector of the seif dunes was approximately 0.11 m/a towards the west(-0.11 m/a),while the mean amplitude of lateral migration was 0.53 m/a,ignoring the direction of lateral *** found that the seif dune field formed first beside seasonal rivers,which can provide sediment,and then expanded downwind.

关键词： seif dune Kumtagh Desert elongation migration drift potential

Spatiotemporal changes in terrestrial water storage in the Beijing-Tianjin Sandstorm Source Region from GRACE satellites

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International Soil and Water Conservation Research 2020年第3期8卷 295-307页

作者： Yingjun Pang bo wu Yanping Cao Xiaohong Jia Institute of Desertification Studies Chinese Academy of ForestryBeijing100091China Key Laboratory of Desert Ecosystem and Global Change State Administration of Forestry and GrasslandBeijing100091China The College of Environment and Planning of Henan University Kaifeng475004HenanChina

The Sandstorm Source Control Project in and around the Beijing-Tianjin region was one of the most important ecological projects in *** water storage(TWS)has important impacts on the ecological construction,agriculture,industry,and resident's *** on the Gravity Recovery and Climate Experiment(GRACE)data,meteorological and Moderate Resolution Imaging Spectroradiometer(MODIS)data,etc.,this paper analyzed spatiotemporal characteristics of TWS,groundwater storage,and precipitation,and explored the influencing factors of regional TWS combined with land use and land cover(LULC),social and economic *** most important results were as follows:(1)From 2003 to 2016,TWS in the Beijing-Tianjin Sandstorm Source Region showed a decreasing trend with a rate of 3.14 mm yr-1.(2)The TWS decline was caused mainly by groundwater overexploitation,but not pre-cipitation variation.(3)Spatiotemporal variations of TWS were related to *** area with the most serious decrease of TWS was mainly located in the southwestern part of the region,where farmland percentage and population density were greater.(4)Reducing the percent of farmland and tree planting,and adding the shrub and grass planting,could be a viable choice for the Beijing-Tianjin Sandstorm Source Control *** results provide a scientific basis for regional water resource and ecological management.

关键词： Terrestrial water storage Beijing-Tianjin Sandstorm Source Region Groundwater LULC