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不同教育法律规定下的“流生”问题分析——教育法规的博弈分析尝试
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作者 罗建河 孙绵涛 《当代教育论坛(宏观教育研究)》 2004年第6期26-28,共3页
本文针对我国当前现实存在的流生问题,试图运用博弈论的基本原理分析不同教育法律规定在解决流生问题中的作用,借以指出现行相关教育法令法规及政策中存在的不足之处,进而指出现行教育法规中普遍存在的弊病。
关键词 教育法律 “流生”问题 博弈论 教育政策 教育观念
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一个都不能少——浅谈初中班级管理中的“流生”问题
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作者 徐艳 《教育艺术》 2017年第5期43-43,共1页
学生和班级是教育的基础构成,在流生问题已经引起广泛关注的情况下,如何解决流生问题也成为班级管理的重点。笔者结合多年教学经验,就初中班级管理中如何解决流生问题进行了探讨、分析。那么,如何控制流生,做好班级管理呢?笔者认为,要... 学生和班级是教育的基础构成,在流生问题已经引起广泛关注的情况下,如何解决流生问题也成为班级管理的重点。笔者结合多年教学经验,就初中班级管理中如何解决流生问题进行了探讨、分析。那么,如何控制流生,做好班级管理呢?笔者认为,要从以下几点做起: 展开更多
关键词 “流生” 班级管理 初中 教学经验 教育
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关于农村初中“流生”现象的原因分析与策略研究
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作者 孙成广 《基础教育研究》 2014年第18期6-7,10,共3页
目前我国义务教育已实行不收学费和杂费的政策,但是在农村初中,"流生"现象依然广泛存在,严重阻碍了我国义务教育向更高、更远的目标迈进。分析"流生"现象出现的缘由,并提出有针对性的意见,迫在眉睫。
关键词 农村初中 “流生”现象 原因与策略
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初中“流生”问题探源及对策
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作者 鲁传扣 《运城高等专科学校学报》 2002年第6期41-41,共1页
关键词 初中 “流生” 中国 失常 原因 对策
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浅谈“流生”的心理成因及其对策
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作者 程冰 《成才之路》 2010年第33期67-68,共2页
长期以来,"流生"问题成了困绕农村中学的一大难题。尽管有《义务教育法》《未成年人保护法》的明文规定;尽管有上级主管部门一年一度的"普九年审",可学校依然是"铁打的营盘流水的兵"。讲道理,谁不能说出一大套?谈措施,哪个学... 长期以来,"流生"问题成了困绕农村中学的一大难题。尽管有《义务教育法》《未成年人保护法》的明文规定;尽管有上级主管部门一年一度的"普九年审",可学校依然是"铁打的营盘流水的兵"。讲道理,谁不能说出一大套?谈措施,哪个学校不是。量化考核,奖惩挂钩”?可与高达20%的辍学率相比,这些显得是那么苍白无力。 展开更多
关键词 “流生” 心理成因 《未成年人保护法》 《义务教育法》 上级主管部门 农村中学 量化考核 辍学率
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职业学校“流生”因素分析及教育管理对策
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作者 吴松阳 颜琴书 +3 位作者 俞浩圣 胡璀 陈清 朱业标 《卫生职业教育》 2010年第4期46-48,共3页
现分析职业学校的“流生”现象及其因素,并针对其因素提出教育管理对策。笔者认为,只有提高认识,想学生所想,改革教育管理模式,落实管理措施,才能稳定学生思想,使其树立学习信心,才能减少“流生”现象。
关键词 “流生”现象 职业学校 因素分析 教育管理
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有效控制“流生”之我见
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作者 朱业标 《卫生职业教育》 2004年第13期41-42,共2页
人们习惯于把没有完成学业,中途辍学的学生称为"流生".据报载,历代人才荟萃的苏南某市,近2年来城乡"流生"达1万余人,这是个惊人的数字.这些本来应该坐在明亮教室里学习文化知识的莘莘学子,却"流"出校门,... 人们习惯于把没有完成学业,中途辍学的学生称为"流生".据报载,历代人才荟萃的苏南某市,近2年来城乡"流生"达1万余人,这是个惊人的数字.这些本来应该坐在明亮教室里学习文化知识的莘莘学子,却"流"出校门,弃"文"就"钱"了.虽然教育行政部门和学校都在大力控流保学,提高适龄学生的入学率、在校学生的巩固率和学生教育的完成率等方面做了大量细致工作,也取得了显著成效.但是流生现象仍然存在,一些偏僻、落后的贫困地区尤为严重,暴露了当前教育中潜伏的问题和危机. 展开更多
关键词 “流生” 控制 措施
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以人文关怀减少流生
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作者 汤成军 《江苏教育(职业教育)》 2009年第1期38-38,共1页
在职业教育蓬勃发展的今天,有一种现象成为职业教育乐章中的不和谐音符,那就是“流生”现象。在控流工作上。我校不仅从教师队伍素质提高、专业课程设置优化、教学质量提升、实验实训设备完备等方面下工夫,还充分发挥我校原师范教育... 在职业教育蓬勃发展的今天,有一种现象成为职业教育乐章中的不和谐音符,那就是“流生”现象。在控流工作上。我校不仅从教师队伍素质提高、专业课程设置优化、教学质量提升、实验实训设备完备等方面下工夫,还充分发挥我校原师范教育的人文优势,努力营造人文校园.坚持以人文留生。 展开更多
关键词 人文关怀 “流生” 教师队伍素质 专业课程设置 职业教育 质量提升 实训设备 人文优势
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中等职校流生现象透析及对策 被引量:2
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作者 魏家禹 《职教通讯(江苏技术师范学院学报)》 2006年第10期20-22,共3页
在职业教育蓬勃发展、渐趋壮大的背后,受内外部环境等多重因素的影响,“流生”现象也越来越凸显,成为当前职教发展中一个不容忽视的问题。对职校的“流生”现象进行透析,找出其原因并提出合理化的建议及对策。
关键词 中等职业学校 透析 对策 “流生”现象 负面影响 办学条件 教学管理
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Rate Law for Photoelectrochemical Water Splitting Over CuO
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作者 Bo-Yuan Gao Wen-HuaLeng 《电化学(中英文)》 CAS 北大核心 2024年第8期17-27,共11页
Photocatalytic splitting of water over p-type semiconductors is a promising strategy for production of hydrogen.However,the determination of rate law is rarely reported.To this purpose,copper oxide(CuO)is selected as ... Photocatalytic splitting of water over p-type semiconductors is a promising strategy for production of hydrogen.However,the determination of rate law is rarely reported.To this purpose,copper oxide(CuO)is selected as a model photocathode in this study,and the photogenerated surface charge density,interfacial charge transfer rate constant and their relation to the water reduction rate(in terms of photocurrent)were investigated by a combination of(photo)electrochemical techniques.The results showed that the charge transfer rate constant is exponential-dependent on the surface charge density,and that the photocurrent equals to the product of the charge transfer rate constant and surface charge density.The reaction is first-order in terms of surface charge density.Such an unconventional rate law contrasts with the reports in literature.The charge density-dependent rate constant results from the Fermi level pinning(i.e.,Galvani potential is the main driving force for the reaction)due to accumulation of charge in the surface states and/or Frumkin behavior(i.e.,chemical potential is the main driving force).This study,therefore,may be helpful for further investigation on the mechanism of hydrogen evolution over a CuO photocathode and for designing more efficient CuO-based photocatalysts. 展开更多
关键词 CUO Photoelectrochemical water splitting Electrochemical impedance spectroscopy Rate law Kinetics of photogenerated carriers
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中等职业学校“留生问题”与班级经营密切相关
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作者 金兰兰 《中国校外教育》 2013年第8期127-128,共2页
从对中职学校班级经营的角度来关注"留生"问题,进而寻求"流生"问题的解决策略。着重从纵向三个层次和横向两个层次把中职学校班级根据学生的具体情况进行细分的基础上,再有针对性地对一些班级经营事务加以说明和探... 从对中职学校班级经营的角度来关注"留生"问题,进而寻求"流生"问题的解决策略。着重从纵向三个层次和横向两个层次把中职学校班级根据学生的具体情况进行细分的基础上,再有针对性地对一些班级经营事务加以说明和探讨,在一切为了解决好"留生"的所有问题的原则下,控制"流生",减少"流生"。 展开更多
关键词 班级经营“留生”“流生”
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Investigating the charge transfer mechanism of ZnSe QD/COF S-scheme photocatalyst for H_(2)O_(2)production by using femtosecond transient absorption spectroscopy
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作者 Yanyan Zhao Chunyan Yang +4 位作者 Shumin Zhang Guotai Sun Bicheng Zhu Linxi Wang Jianjun Zhang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期258-269,共12页
Hydrogen peroxide(H_(2)O_(2))has gained widespread attention as a versatile oxidant and a mild disin-fectant.Here,an electrostatic self-assembly method is applied to couple ZnSe quantum dots(QDs)with a flower-like cov... Hydrogen peroxide(H_(2)O_(2))has gained widespread attention as a versatile oxidant and a mild disin-fectant.Here,an electrostatic self-assembly method is applied to couple ZnSe quantum dots(QDs)with a flower-like covalent organic framework(COF)to form a step-scheme(S-scheme)photocata-lyst for H_(2)O_(2)production.The as-prepared S-scheme photocatalyst exhibits a broad light absorption range with an edge at 810 nm owing to the synergistic effect between the ZnSe QDs and COF.The S-scheme charge-carrier transfer mechanism is validated by performing Fermi level calculations and in-situ X-ray photoelectron and femtosecond transient absorption spectroscopies.Photolumi-nescence,time-resolved photoluminescence,photocurrent response,electrochemical impedance spectroscopy,and electron paramagnetic resonance results show that the S-scheme heterojunction not only promotes charge carrier separation but also boosts the redox ability,resulting in enhanced photocatalytic performance.Remarkably,a 10%-ZnSe QD/COF has excellent photocatalytic H_(2)O_(2)-production activity,and the optimal S-scheme composite with ethanol as the hole scavenger yields a H_(2)O_(2)-production rate of 1895 mol g^(-1)h-1.This study presents an example of a high-performance organic/inorganic S-scheme photocatalyst for H_(2)O_(2)production. 展开更多
关键词 ZnSe quantum dot Covalent organic framework S-scheme heterojunction Carrier migration and separation H_(2)O_(2)production
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Biomass, litterfall and the nutrient fluxes in Chinese fir stands of different age in subtropical China 被引量:18
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作者 马祥庆 刘春江 +2 位作者 Ilvesniemi Hannu Carl J.Westman 刘爱琴 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期165-170,250,共6页
Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), a fast-growing, ever-green conifer tree with high yield and excellent quality, is the most important tree species of timber plantations in subtropical China. We inv... Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), a fast-growing, ever-green conifer tree with high yield and excellent quality, is the most important tree species of timber plantations in subtropical China. We investigated the characteristics of biomass, litterfall and nutrient fluxes in the 8, 14 and 24 year-old stands, representing the young, middle-aged and mature stands. The results showed that Chinese fir plantations in central Fujian province had high productivity, and the proportion of stem mass in total biomass was between 50%-70%. Chinese fir was low nutrient-return tree species with litterfall. Nutrient withdrawal from senescing needles was a strong age-dependence for nitrogen, phosphorous and potassium in Chinese fir. With a management system of such short-rotation and continuously pure-crop planting, harvesting timber can lead to great nutrient loss, which may be one of the causes for site degradation. 展开更多
关键词 Chinese fir BIOMASS PRODUCTIVITY Litter fall Nutrient flux
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Phase-field simulations of forced flow effect on dendritic growth perpendicular to flow 被引量:4
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作者 王智平 王军伟 +2 位作者 朱昌盛 冯力 肖荣振 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期612-617,共6页
The effect of supercooled melt forced laminar flow at low Reynolds Number on dendritic growth perpendicular to melt flow direction was investigated with the phase-field method by incorporating melt convection and ther... The effect of supercooled melt forced laminar flow at low Reynolds Number on dendritic growth perpendicular to melt flow direction was investigated with the phase-field method by incorporating melt convection and thermal noise under non-isothermal condition. By taking the dendritic growth of high pure succinonitrile (SCN) supercooled melt as an example, side-branching shape difference of melts with flow and without flow was analyzed. Relationships among supercooled melt inflow velocity, deflexion angle of dendritic arm and dendritic tip growth velocity were studied. Results show that the melt inflow velocity has few effects on the dendritic tip growth velocity. A formula of relationship between the velocity of the melt in front of primary dendritic tip and the dendritic growth time was deduced, and the calculated result was in quantitative agreement with the simulation result. 展开更多
关键词 phase-field method laminar flow dendritic growth computer simulation SOLIDIFICATION flow velocity
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Study on Eco-restoration of Polluted Rivers 被引量:1
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作者 万玉山 邹涛 +1 位作者 邵敏 李定龙 《Agricultural Science & Technology》 CAS 2016年第10期2386-2389,2409,共5页
[Objective] This study was conducted to find a restoration method suitable for urban polluted rivers. [Method] A segment of a representative river in the old part of a certain city in south Jiangsu was selected as a r... [Objective] This study was conducted to find a restoration method suitable for urban polluted rivers. [Method] A segment of a representative river in the old part of a certain city in south Jiangsu was selected as a research area through previous investigation, and the polluted river was cleaned and restored by 3 methods, i.e. artificial wetland, floating island type wetland and purification floating island. [Resuit] Floating plants (Hydrocotyle verticillata and Myriophyllum spicatum) showed better restoration effects than emergent aquatic plants (Iris wilsonii, Arundo donax, reed, water-cultured Ilex chinensis and Lythrum salicaria). The two types of plants showed the removal rates of total nitrogen of 37.9% and 34.1%, respectively, the removal rates of total phosphorous of 80.1% and 73.5%, respectively, the removal rates of COD of 81.1% and 74.8%, respectively, the removal rates of ammonia nitrogen of 80.6% and 85.9%, respectively, and the removal rates of SS of 59.1% and 77.3%, respectively. Among the purification floating island, the artificial wetland and the floating island type wetland, the purification floating land restoration technique exhibited the best removal effect, with the removal rates of 87.6%, 71.3%, 87.6%, 97.5% and 81.8% for total nitrogen, total phosphorous, ammonia nitrogen COD and SS, respectively. The nitrification and denitdfication rates of bottom mud and water samples in the engineering segment were remarkably higher than those in the reference segment, by 15.4% and 21.1%, respectively. The nitrification and denitrification rates of bottom mud in the engineering segment and the non-engineering segment were higher than those of water samples by 26.9% and 31.8%, respectively. Restoration plants showed better removal effects of total phosphorous, total nitrogen, COD and SS under aeration condition than noeration condition. [Conclusion] The purification floating island has a significant restoration effect on urban polluted river. 展开更多
关键词 Polluted Rivers Eco-restoration AERATION
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Review of forest ecology studies in China 被引量:3
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作者 王庆礼 邓红兵 +1 位作者 王绍先 李杨 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期231-234,252,共4页
As the most important type or component in the terrestrial ecosystems, forest ecosystem makes its role obviously prominent and important on environment and human being. It possesses non-substitutable functions in the ... As the most important type or component in the terrestrial ecosystems, forest ecosystem makes its role obviously prominent and important on environment and human being. It possesses non-substitutable functions in the process of sustainable development. However, due to the complexity of the forest ecosystem and the relatively delay or lack of the related research technology, the science is still in the case of immature and questions. This paper summarized and reviewed briefly the development and the present case of the forest ecology, then pointed out the existing problems in the forest ecosystem researches. In the end, we discussed several fields that need to pay more attention to in future researches. 展开更多
关键词 FOREST ECOSYSTEM Forest ecology Structure and function MANAGEMENT HEALTH WATERSHED
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Study on Purification Efficiency of Vertical Flow Wetlands on Domestic Wastewater 被引量:7
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作者 仝昭昭 王延华 顾中铸 《Agricultural Science & Technology》 CAS 2011年第3期461-465,共5页
The combination method of intermittent influent and vertical flow wetlands (VFW) was used in the test to treat the domestic wastewater. Four artificial wetlands including Typha latifolia wetland,Phragmites australis... The combination method of intermittent influent and vertical flow wetlands (VFW) was used in the test to treat the domestic wastewater. Four artificial wetlands including Typha latifolia wetland,Phragmites australis (P.H.) wetland,polyculture wetlands (Typha latifolia and Phragmites australis) and non-vegetation wetland were established in the test. The effects of hydraulic retention time (HRT) and plant species on pollutants removal efficiencies were studied. The results showed that when HRT=7,the treatment efficiencies of wetlands with plants for the removal of TN and NH+4-N were up to 99.65% and 99.58%,respectively. For the control wetland,TN removal efficiency was up to 87.9% when HRT were 6 days,and NH+4-N removal efficiency was up to 91.8% when HRT were 5 days. TP removal efficiencies of four wetlands were higher than 93% when HRT was 6 days. Through the studies on different plants,it was found that vegetation wetlands had better nitrogen removal efficiency than non-vegetation wetland. The treatment efficacy of Phragmites australis wetland and polyculture wetland was better than Typha latifolia wetland. 展开更多
关键词 Vertical flow wetlands Domestic wastewater Removal of nitrogen and phosphorus Hydraulic retention time
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Phase-field simulation of forced flow effect on random preferred growth direction of multiple grains 被引量:1
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作者 王军伟 朱昌盛 +2 位作者 王智平 冯力 肖荣振 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1620-1626,共7页
The random distribution problem of dendrite preferred growth direction was settled by random grid method.This method was used to study the influence of forced laminar flow effect on multiple grains during solidificati... The random distribution problem of dendrite preferred growth direction was settled by random grid method.This method was used to study the influence of forced laminar flow effect on multiple grains during solidification.Taking high pure succinonitrile (SCN) undercooled melt as an example,the forced laminar flow effect on multiple grains was studied by phase-field model of single grain which coupled with flow equations at non-isothermal condition.The simulation results show that the random grid method can reasonably settle the problem of random distribution and is more effective.When the solid fraction is relatively low,melt particles flow around the downstream side of dendrite,and the flow velocity between two dendrite arms becomes high.At the stage of solidification time less than 1800Δt,every dendrite grows freely;the upstream dendrites are stronger than the downstream ones.The higher the melt flow rate,the higher the solid fraction.However,when the solid fraction is relatively high,the dendrite arm intertwins and only a little residual melt which is not encapsulated can flow;the solid fraction will gradually tend to equal to solid fraction of melt without flow. 展开更多
关键词 phase-field method multiple grains laminar flow preferred growth direction computer simulation SOLIDIFICATION flow velocity
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Effect of High-Gate-Voltage Stress on the Reverse Gated-Diode Current in LDD nMOSFET’s 被引量:2
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作者 陈海峰 郝跃 马晓华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第5期875-878,共4页
The reverse generation current under high-gate-voltage stress condition in LDD nMOSFET's is studied. We find that the generation current peak decreases as the stress time increases. We ascribe this finding to the dom... The reverse generation current under high-gate-voltage stress condition in LDD nMOSFET's is studied. We find that the generation current peak decreases as the stress time increases. We ascribe this finding to the dominating oxide trapped electrons that reduce the effective drain bias, lowering the maximal generation rate. The density of the effective trapped electrons affecting the effective drain bias is calculated with our model. 展开更多
关键词 generation current high gate voltage stress trapped electron
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Non-premixed Combustion Model of Fluidized Bed Biomass Gasifier for Hydrogen-Rich Gas 被引量:1
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作者 周密 闫立峰 +1 位作者 郭庆祥 朱清时 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期131-136,共6页
Fluidized bed biomass gasifiers can be employed to produce hydrogen-rich gas. A non-premixed combustion model is used for biomass air-steam gasification in the gasifier, and the simulations were carried out by using t... Fluidized bed biomass gasifiers can be employed to produce hydrogen-rich gas. A non-premixed combustion model is used for biomass air-steam gasification in the gasifier, and the simulations were carried out by using the FLUENT 6.0 software. The simulation results are compared with the experimental data. The effects of the steam to biomass ratio (S/B), the equivalence ratio (ER), and the size of biomass particles on the hydrogen yield were studied. Meanwhile, the distributions of hydrogen inside the gasifier at different conditions are also described. 展开更多
关键词 CFD BIOMASS GASIFICATION HYDROGEN
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