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| 1 | Re-examination of the effect of ownership structure on financial reporting: Evidence from share pledges in China显示文摘In this paper, we present evidence that firms with concentrated ownership manage earnings when their large shareholders have an incentive to do so.The large shareholders of Chinese public firms often pledge their shares for loans. Before the split share reform in 2006, loan terms were based on the book value of the firm. Since then, the share price has become critical for share pledged loans. We postulate that the reform triggered large shareholders' incentive to influence financial reports. Using a sample of non-state-owned enterprises, we test the effect of share pledges on earnings smoothing and how this effect changes after the reform. Our results suggest that share pledging firms smooth their earnings more than other firms, but these results are only found after the split share reform. Accordingly, our results provide more direct evidence on the effect of ownership concentration on financial reporting. | Zhizhong Huang Qingmei Xue | 2016 | China Journal of Accounting Research2016,,2: | 58 |
| 2 | TRANSPORT OF THE SUSPENDED SEDIMENT IN THE CHANGJIANG ESTUARY显示文摘The Changjiang River is characterized by the enormous volume of runoff and the great amount of sediment load with remarkable seasonal variation. The annual runoff sometimes is respondent to the amount of sediment load, and sometimes not. The amount of monthly sediment load after the month of the maximum runoff is larger than those before the month. The sediment concentration and net quantity of sediment transport in the vicinity of the river mouth varies greatly in time between the ebb and flood, spring and neap, and dry seasons and flood seasons. The three bifurcations also have differences in concentration and net quantity in space. Even in the same bifurcation they have differences in and out of the sand bar. At present, the North Channel is the main passage for water and sediment load emptying into the sea from the Changjiang River. More than 50 percent of the sediments from the river basin are deposited nearby the South Branch entrance and the main depositional area is situated in subaqueous delta off the South Channel. Between 122°30’E and 123°E is an important boundary for eastward sediment dispersion from which the suspended sediment are dispersed towards the east by south. | SHEN Huanting Institute of Esturaine and Coastal Research, East China Normal University, Shanghai, China LI Jiufa Institute of Esturaine and Coastal Research, East China Normal University, Shanghai, China ZHU Huifang Institute of Esturaine and Coastal Research, East China Normal University, Shanghai, China HAN Mingbao Institute of Esturaine and Coastal Research, East China Normal University, Shanghai, China ZHOU Fugen Department of Marine Geology, Tongji Univcrsity, Shanghai, China | 1992 | International Journal of Sediment Research1992,7,3: | 37 |
| 3 | Effects of sunspot cycle length and CO_2 on air temperature along Qinghai-Xizang railway and air temperature's trend prediction显示文摘There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temperature series along the Qinghai-Xizang railway (Trw) from 1935 to 2000 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 15-year lagged concentration of atmospheric carbon dioxide (CO2), and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2), respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93a, 108a, 205a and 275a. The result shows that the SCL would be becoming longer in the first half of the 21st century, and then it could be becoming shorter in the second half of the 21st century. Based on the natural change of SCL and the effect of double CO2 concentration, Trw in the 21st century is forecasted. It could warm up about 0.50℃ in the first half of the 21st century compared with the last decade of last century. The mean maximum air temperature could be likely about 0.20℃ in July and from 0.40℃ to 1.10℃ in January. The annual air temperature difference would likely reduce 0.3-1.00℃. The probability of above predictions ranges from 0.64 to 0.73. | LI Dongliang, QUO Hui, WANG Wen & WEI LiCold & Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Science, Lanzhou 730000, China Department of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China | 2004 | Science China Earth Sciences2004,47,z1: | 28 |
| 4 | The characteristics of atmospheric CO_2 concentration variation of four national background stations in China显示文摘Atmospheric carbon dioxide is an important kind of greenhouse gas which influences global temperature. Its concentration variation could indicate the distribution of human and natural activities in various regions. Through the non-dispersive infrared method, flask sampling of atmospheric CO2 concen- tration was measured weekly at four national background stations including Waliguan, Shangdianzi, Lin’an, and Longfengshan. Based on the data collected from September 2006 to August 2007, along with the Waliguan station’s experience on in situ observational data processing, the selection methods for sampling data through the atmospheric background CO2 concentration analysis were preliminarily discussed. On the basis of this result, the variation features of the four typical regions’ atmospheric background CO2 concentration was analyzed for the first time. The results show that the atmospheric CO2 concentration at Waliguan, Shangdianzi, Lin’an, and Longfengshan is 383.5, 385.9, 387.8, and 384.3 ppm, respectively. During the research period, CO2 concentration at the Waliguan station changed slightly. However, the CO2 concentration changed sharply at the Shangdianzi and the Lin’an stations due to the great influence of human activities in the Jingjinji and the Changjiang Delta economic zones, and changed regularly with seasons at Longfengshan station under dual influences of human activities and plant photosynthesis. The results from this study can lay the foundation for more profound studies on atmospheric CO2 concentration level of different areas in China, and could be used to improve the understanding of carbon source and sink distribution. | LIU LiXin, ZHOU LingXi, ZHANG XiaoChun, WEN Min, ZHANG Fang, YAO Bo & FANG ShuangXi Key Laboratory for Atmospheric Chemistry, Centre for Atmosphere Watch and Services (CAWAS), Chinese Academy of Meteoro- logical Sciences (CAMS), China Meteorological Administration (CMA), Beijing 100081, China | 2009 | Science China Earth Sciences2009,52,11: | 26 |
| 5 | 卫星遥感监测近地表细颗粒物多元回归方法研究显示文摘对地基监测PM2.5和气象数据、MODISAOD卫星数据与NCEP FNL数据进行了处理分析,在与一元简单线性模型(模型1)进行对比的基础上,建立了适应于北京及其附近地区遥感监测近地面颗粒物(PM2.5)浓度的多元线性(模型2)和非线性(模型3)回归模型,并对模型进行了评价验证和遥感监测初步应用.结果表明:模型1,2,3分别能够解释PM2.5 32.5%,56.1%,62.7%的变异.反演的PM2.5浓度与站点监测值相关性分别为0.5488(R2=0.3012),0.7449(R2=0.5549),0.7431(R2=0.5523).对于站点监测PM2.5浓度63.1652μg/m3的均值,反演均方根误差RMSE分别为43.5562,35.3321,36.8450μg/m3.模型2和3中气象因子分别能够解释PM2.5 23.6%和12.6%的变异,说明了气象因子影响北京地区春季PM2.5-AOD关系的显著性.3种模型整体上都不同程度地存在着低值高估和高值低估的现象. | 贾松林 苏林 陶金花 王子峰 陈良富 尚华哲 | 2014 | 中国环境科学2014,34,3: | 21 |
| 6 | Effect of different concentrations of surfactant on the wettability of coal by molecular dynamics simulation显示文摘Anionic surfactant sodium dodecyl benzene sulfonate(SDBS)at varying concentrations was selected to investigate the influence on the wettability of Zhaozhuang Coal by molecular dynamics simulation.Six groups of water/surfactant/coal systems with different concentrations were constructed.The influence of surfactant with different concentrations on the wettability of coal was concluded by analyzing various properties from the energetic behaviors to the dynamic characteristics.The results show that the interfacial tension decreases sharply and then rises slowly with the increase of SDBS surfactant concentration,obtaining that surfactants can obviously reduce the interfacial tension.The surfactant molecules could be detected at the water/coal interface through analyzing the system’s relative concentration distribution.In addition,the difference in the wettability of surfactants on coal surfaces is caused by the spatial distribution differences of alkyl chains and the benzene ring of the surfactant molecules.And the negative interaction energy between SDBS and the coal surface indicates that adsorption process is spontaneous.Furthermore,it is of great practical significance for improving the dust reduction effect and reducing the disaster of coal dust by exploring the effects of surfactant molecules on the wettability of coal. | Junqing Meng Feifei Yin Shichao Li Ruquan Zhong Zeyuan Sheng Baisheng Nie | 2019 | International Journal of Mining Science and Technology2019,29,4: | 20 |
| 7 | 大气CO_2浓度和温度升高对超级稻生长发育的影响显示文摘利用稻田FACE(Free Air gas Concentration Enrichment)系统,设置对照(Ambient, 环境空气)、CO2浓度增高(EC,比Ambient增200 μmol·mol-1)、温度增高(ET,比Ambient增2 ℃)和CO2浓度与温度同步增高(EC+ET)4个处理,研究其对超级杂交籼稻Ⅱ优084生长发育的影响。结果表明:与Ambient相比,EC或EC+ET使水稻抽穗和成熟期推迟1~3 d,但ET对生育期没有影响;EC、EC+ET使水稻成熟期单茎干重分别增加49%、40%,均达显著水平,但ET则呈相反趋势;与Ambient相比,EC使成熟期叶片、茎鞘、稻穗及地上部干重分别增加40%、69%、30%和39%,均达极显著水平;ET使对应部位干重分别减少11%、21%、31%和26%,除茎鞘外均达显著或极显著水平;EC+ET使对应部位干重分别增加40%、47%、10%和18%,除稻穗外均达显著水平;抽穗期和抽穗后20 d各器官干重及地上部总重对各处理的响应趋势一致,但幅度明显小于成熟期;与生物量不同,各处理对结实期物质分配比例影响较小;EC、EC+ET使水稻成熟期茎鞘非结构性碳水化合物浓度和含量显著增加,但ET表现出相反趋势。综上所述,大气CO2浓度和温度同时升高情形下,超级稻Ⅱ优084收获期茎鞘同化物浓度和含量、各器官干重以及地上部生长总量均明显增加,但增幅略小于单独CO2浓度升高环境下生长的水稻。 | 赖上坤 庄时腾 吴艳珍 王云霞 朱建国 杨连新 王余龙 | 2015 | 生态学杂志2015,34,5: | 20 |
| 8 | Methane and nitrous oxide concentration and emission flux of Yangtze Delta plain river net显示文摘Methane (CH4) and nitrous oxide (N2O) saturation concentration and gas-water interface emission flux in surface water of the Yangtze Delta plain river net were investigated in summer at representative sites including the upper reaches of the Huangpu River and the rivers in the Chongming Island. The results show that the CH4 concentration in river water ranged from 0.30±0.03 to 6.66±0.14 μmol.L-1, and N2O concentration ranged from 13.8±2.33 to 435±116 nmol.L-1. River surface water had a very high satura- tion level of CH4 (from 468±49.0% to 11560±235%) and that of N2O (from 175±29.5% to 4914±1304%). Dissolved oxygen (DO) was the primary factor controlling the CH4 concentration in water. N2O concentration had significant negative correlation with salinity and a significant positive correlation with nitrate (NO3-), nitrite (NO2-), chemical oxygen demand (CODcr) concentration and pH of river water. CH4 and N2O of river water were brought about mainly by methanogenesis and denitrification in river bottom sediment that diffused through sediment-water interface into the water body and then into atmosphere through the gas-water interface. The emission flux of CH4 and N2O at river gas-water interface reached 778±59.8 and 236±63.6 μmol.m-2.h-1, respectively in summer. The river net was a potential source of atmospheric CH4 and N2O because of eutrophication of the water body. | WANG DongQi CHEN ZhenLou SUN WeiWei HU BeiBei XU ShiYuan | 2009 | Science China Chemistry2009,52,5: | 19 |
| 9 | Three-dimensional Finite Element Analysis of the Mechanical Properties of Helical Thread Connection显示文摘Conventional analytical and numerical methods for the mechanical properties of helical threads are relied on many assumptions and approximations and thus hardly yield satisfied results. A parameterized 3D finite element model of bolted joints with real helical thread geometry is established and meshed with refined hexahedral elements. The Von Mises plasticity criterion, kinematic hardening rule of materials and interfacial contacts are employed to make it possible for the suggested model be able to approach real assembly conditions. Then, the mechanical properties of bolted joints with different thread pitches, thread numbers and modular ratios are investigated, including the contact pressure distribution at joint interfaces, the axial load distribution and stress concentration in screw threads during the loading and unloading process. Simulation results indicate that the load distribution in screw threads produced by the suggested model agrees well the results from CHEN's photoelastic tests. In addition, an interesting phenomenon is found that tightening the bolt with a large preload first and then adjusting the clamping force by unloading can make the load distribution more uniform and reduce the maximum residual equivalent stress in thread roots by up to 40%. This research provides a simple and practical approach to constructing the 3D finite element model and predicting the mechanical properties of helical thread connection. | YANG Guoqing HONG Jun ZHU Linbo LI Baotong XIONG Meihua WANG Fei | 2013 | Chinese Journal of Mechanical Engineering2013,26,3: | 19 |
| 10 | Deep-seated structure and metallogenic dynamics of the Ailaoshan polymetallic mineralization concentration area, Yunnan Province, China显示文摘The Ailaoshan poly-metallic mineralization concentrated area (MCA) consists of the well known Ailaoshan metallogenic belt and adjacent mineral districts and/or deposits. Located in an area of several complex and intersecting tectonic units, the Ailaoshan poly-metallic MCA is controlled by deep crustal and mantle tectonism. Through interpretation of remote sensing images, we identified a large ring structure system that surrounds the MCA. This ring structure encloses regional deep-crustal faults, ductile shear zones, geothermal anomalies, magmatic rocks, and the major mineral deposits, all of which are the reflections of deep tectonic geodynamics that have been long active in this area. Geophysical data indicate that the crust is comprised of relatively stable two or three layers, with some irregular lower-velocity belts. The Moho in the ring sutures occurs as an area of local uplift. There exists an obvious transitional zone between the crust and mantle boundaries. Asthenopheric mantle shows multi-layer upwelling, which indicates multiple events during different geological epochs. It is believed that these mantle events or pulses were responsible for the formation of the regional shear zones, magmatic rocks, and polymetallic orebodies. Furthermore, an integrated metallogenic dynamics model related to the asthenopheric upwelling pulses in the MCA is established, defining events as old as Late Paleozoic. | GE LiangSheng DENG Jun GUO XiaoDong ZOU YiLin LIU YinChun | 2009 | Science China Earth Sciences2009,52,10: | 16 |
| 11 | SCATTERING OF FLEXURAL WAVES AND DYNAMIC STRESS CONCENTRATIONS IN MINDLIN'S THICK PLATES WITH A CUTOUT显示文摘Using the complex variable method and conformal mapping,scat-tering of flexural waves and dynamic stress concentrations in Mindlin’s thick plateswith a cutout have been studied.The general solution of the stress problem of thethick plate satisfying the boundary conditions on the contour of cutouts is obtained.Applying the orthogonal function expansion technique,the dynamic stress problemcan be reduced into the solution of a set of infinite algebraic equations.As examples,numerical results for the dynamic stress concentration factor in Mindlin’s plates witha circular,elliptic cutout are graphically presented in sequence. | 刘殿魁 胡超 | 1996 | Acta Mechanica Sinica1996,12,2: | 16 |
| 12 | Al_(80)Ni_6Y_8Co_4Cu_2 GLASS ALLOYS CONTAINING NANOSCALEPARTICLES BY ISOTHERMAL ANNEALING OR QUENCHING显示文摘Al80Ni6 Y8 Co4 Cu2 amorphous ribbons were isothermally annealed and a mixed structure consisting of α-Al particle with a size of less than 15nm and Al3Ni compound with a size of about 30nm was obtained. The crystallization kinetics of Al80Ni6 Y8 Co4 Cu2 amorphous alloy shows that the precipitation of α-Al particles is the growth process controlled by diffusion of the solute elements rejected from the growing crystals. By quenching at different cooling rates, a mixed structure consisting of nanoscale α-Al particles and the remaining glass matrix or structure consisting of nanoscale particle (Al phase or Al3Ni compound) with a size of about 100nm was formed. The addition of Co elements and Cu elements to Al-Ni-Y alloy systems increases the glass formation ability of the alloy and the thermal stability of the supercooled liquid region against crystallization, which results from significant difference of atomic size, strong bonding nature among constituent elements and the low diffisivity of the solute elements due to the concentration gradient in the growing front of crystals. | Z. Bian, G. He and G.L. Chen (State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China) J. Lu, D.J. Chen, G.C. Tu, G.J. Chen and X.J. Hu (Shougang Metallurgical Research Institute, Beijing | 2000 | Acta Metallurgica Sinica(English Letters)2000,13,5: | 16 |
| 13 | CAVITATED BIFURCATION FOR COMPOSED COMPRESSIBLE HYPER-ELASTIC MATERIALS显示文摘The cavitated bifurcation problem in a solid sphere composed of two compressible hyper-elas-tic materials is examined.The bifurcation solution for the composed sphere under a uniform radial tensileboundary dead-load is obtained.The bifurcation curves and the stress contributions subsequent to the cavita-tion are given.The right and left bifurcation as well as the catastrophe and concentration of stresses are ana-lyzed.The stability of solutions is discussed through an energy comparison. | Ren Jiusheng Cheng Changjun | 2002 | Acta Mechanica Solida Sinica2002,15,3: | 16 |
| 14 | On the physical model of earthquake precursor fields and the mechanism of precursors'timespace distribution──origin and evidences of the strong body earthquake──generating model显示文摘Onthephysicalmodelofearthquakeprecursorfieldsandthemechanismofprecursors'timespacedistribution──originandevidencesof thestron... | 梅世蓉 | 1995 | Acta Seismologica Sinica(English Edition)1995,8,3: | 16 |
| 15 | 自由空气中臭氧浓度升高对大豆的影响显示文摘人类活动导致的大气和气候变化将极大地改变作物未来的生长环境,其中一个显著的变化就是近地层空气污染物臭氧浓度的迅速上升:从工业革命前低于10nL/L上升到现在的50nL/L(夏季每天8h平均),最新预测这一浓度将在2015-2050年增加20%-25%,本世纪末将增加40%-60%。目前大气背景臭氧浓度已经超过敏感植物的伤害阀值(即40nL/L),广泛地造成农作物减产,而未来臭氧浓度增加将使这种影响变得更为严重。与封闭式和开顶式试验相比,FACE(free-air gas concentration enrichment)研究使用标准的作物管理技术,在完全开放的农田条件下运行,代表了人类对未来大气环境的最好模拟。作为人类食物蛋白的重要来源,大豆是世界上种植面积最大的双子叶植物,也是1年生C3作物的模式作物,同时也被认为对臭氧污染最为敏感的作物之一。美国伊利诺伊大学的大豆FACE(SoyFACE)是世界上第1个利用FACE技术开展农作物对高浓度臭氧(模拟本世纪中叶近地层臭氧浓度)响应和适应的多学科合作研究。在阐述气室研究的局限性和介绍SoyFACE运行特点的基础上,首次综述了FACE情形下高浓度臭氧对大豆光合特性、冠层结构、物质生产与分配、产量及其构成因素以及虫害等方面的影响,并比较了FACE与气室研究结果的异同点。SoyFACE研究清楚地表明臭氧对未来粮食安全的影响必须作为一个重要的全球变化因子来加以考虑。利用FACE技术深入开展臭氧及其与其它全球变化因子的互作对世界主要粮食作物的影响、机制和调控的系统研究,是该领域未来优先考虑的方向。 | 杨连新 王云霞 赵秩鹏 朱建国 J.D.Sun 王余龙 | 2010 | 生态学报2010,30,23: | 16 |
| 16 | A Short Text Classification Method Based on N-Gram and CNN显示文摘Text classification is a fundamental task in Nature language process(NLP) application. Most existing research work relied on either explicate or implicit text representation to settle this kind of problems, while these techniques work well for sentence and can not simply apply to short text because of its shortness and sparseness feature. Given these facts that obtaining the simple word vector feature and ignoring the important feature by utilizing the traditional multi-size filter Convolution neural network(CNN) during the course of text classification task, we offer a kind of short text classification model by CNN, which can obtain the abundant text feature by adopting none linear sliding method and N-gram language model, and picks out the key features by using the concentration mechanism, in addition employing the pooling operation can preserve the text features at the most certain as far as possible. The experiment shows that this method we offered, comparing the traditional machine learning algorithm and convolutional neural network, can markedly improve the classification result during the short text classification. | WANG Haitao HE Jie ZHANG Xiaohong LIU Shufen | 2020 | Chinese Journal of Electronics2020,29,2: | 15 |
| 17 | Seasonal,neap-spring variation of sediment concentration in the joint area between Yangtze Estuary and Hangzhou Bay显示文摘An analysis of variations in suspended sediment concentration (SSC) over one year is presented for the joint area between the Yangtze Estuary and the Hangzhou Bay. Results suggest that daily SSC presents periodic variations, which correspond with seasonal and neap-spring tidal cycle. SSCs are higher during the winter season and during spring tides when compared with summer and neap-tide conditions. Furthermore, data indicate that wave and tidal currents are the two dominant factors affecting SSC. Although the Yangtze River discharges abundant sediments to the study area, it does not directly affect concentration variations. But the changing path of the Yangtze River plume plays a certain role in the seasonal variations of SSC. Finally, the calculation of bottom stresses suggests that SSC is a function of both wave and tide-induced resuspension. | 陈沈良 | 2001 | Science China Chemistry2001,44,S1: | 15 |
| 18 | Scattering of SH-wave by multiple circular cavities in half space显示文摘In this paper, an analytic method is developed to address steady SH-wave scattering and perform dynamic analysisof multiple circular cavities in half space. The scattered wave function used for scattering of SH-waves by multiple circularcavities, which automatically satisfies the stress-free condition at the horizontal surface, is constructed by applying thesymmetry of the SH-wave scattering and the method of multi-polar coordinates system. Applying this scattered wave functionand method of moving coordinates, the original problem can be transformed to the problem of SH-wave scattering by multiplecircular cavities in the full space. Finally, the solution of the problem can be reduced to a series of algebraic equations andsolved numerically by truncating the infinite algebraic equations to the finite ones. Numerical examples are provided for casewith two cavities to show the effect of wave number, and the distances between the centers of the cavities and from the centersto the ground surface on the dynamic stress concentration around the cavity impacted by incident steady SH-wave. | 王国庆 刘殿魁 | 2002 | Earthquake Engineering and Engineering Vibration2002,1,1: | 14 |
| 19 | 铅镉复合污染对水稻生长及产量的影响(摘要)(英文)显示文摘[目的]探讨铅镉复合污染对水稻生长、产量及品质的伤害及机理。采用盆栽试验,研究了不同程度的铅镉复合污染对水稻生长发育及产量品质的影响。[结果]铅镉低浓度胁迫能够促进水稻生长,高浓度抑制水稻的株高;铅镉胁迫显著降低了水稻的分蘖数,随着胁迫浓度增加,分蘖数下降幅度增大;铅镉胁迫显著降低了水稻每盆穗数、结实率、千粒重和产量,低浓度胁迫下每穗总粒数显著增加,高浓度胁迫下每穗总粒数显著降低;铅镉低浓度胁迫下糙米率和精米率显著增加,高浓度胁迫下糙米率和精米率显著降低,整精米率随处理浓度的增加而显著下降;水稻籽粒中铅镉含量与土壤中铅镉浓度成显著正相关,土壤铅镉含量达到中高浓度时,水稻籽粒铅镉含量严重超标,铅镉最高超标达333%和122%。[结论]该研究为污染地区水稻栽培技术体系的建立提供依据。 | 王永强 肖立中 李诗殷 郭杨 蔡信德 | 2010 | Agricultural Science & Technology2010,11,5: | 14 |
| 20 | Simulation of rainfall-runoff and watershed convergence process in the upper reaches of Heihe River Basin,July 2002显示文摘The watershed flow concentration scheme in the distributed hydrology-soil- vegetation model (DHSVM) is coupled with the mesoscale atmospheric model MM5 version 3.5, in which the Oregen States University land surface model (OSULSM) was involved. The flood event which happened in July 2002 in the upper reaches of Heihe river basin is simulated and the surface flow convergence process is shown with this coupled model. It has been concluded that times water head reaches each place of the basin are different. Water amount at each point is split-flow proportionally as the drops in elevation between it and neighbor points. Large part of the water amount pass away in greater slope direction and small part pass away in smaller slope one.Adding of the slope convergence makes the atmospheric model redistributes the surface water laterally. | GAO Yanhong L(U) Shihua CHENG Guodong | 2004 | Science China Earth Sciences2004,47,z1: | 13 |