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Cross-Linguistic Evidence for Distinguishing between Effected and Affected Objects
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作者 邵光庆 《海外英语》 2013年第20期295-296,共2页
In today's academic field, the motivation for distinguishing between the effected and the affected objects has received scant attention. This article attempts to probe into this question by citing the related cros... In today's academic field, the motivation for distinguishing between the effected and the affected objects has received scant attention. This article attempts to probe into this question by citing the related cross-linguistic evidence to justify such a distinction. It concludes that some grammatical constructions or linguistic phenomena across languages cannot be well interpreted without the framework of effected-/affected-object dichotomy. Both types of objects show prototypical properties of direct objects, and they are complementary in the realization of direct-objecthood. 展开更多
关键词 cross-LINGUISTIC EVIDENCE effected OBJECTS Affecte
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The effect of dynamical screening on helium(e,2e) fully differential cross-sections
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作者 孙世艳 贾祥富 +4 位作者 苗向阳 张均锋 谢祎 李雄伟 师文强 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2744-2748,共5页
This paper presents the fully differential cross sections (FDCS) for 102eV electron impact single ionization of helium for both the coplanar and perpendicular plane asymmetric geometries within the framework of dyna... This paper presents the fully differential cross sections (FDCS) for 102eV electron impact single ionization of helium for both the coplanar and perpendicular plane asymmetric geometries within the framework of dynamically screened three-Coulomb-wave theory. Comparisons are made with the experimental data and those of the three-Coulomb wave function model and second-order distorted-wave Born method. The angular distribution and relative heights of the present FDCS is found to be in very good agreement with the experimental data in the perpendicular plane geometry. It is shown that dynamical screening effects are significant in this geometry. Three-body coupling is expected to be weak in the coplanar geometry, although the precise absolute value of the cross section is still sensitive to the interaction details. 展开更多
关键词 fully differential cross sections screening effects perpendicular plane geometry
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Nucleus-Nucleus Effects in Fully Differential Cross Sections for Energetic C6++He Collisions with Small Momentum Transfer
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作者 陆晨文 安文芳 +1 位作者 孙世艳 贾祥富 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期35-38,共4页
The modified Coulomb-Born approximation with and without the internuclear interaction (MCB-NN and MCB) is used to calculate the fully differential cross sections (FDCS) for the single ionization of helium by lOO M... The modified Coulomb-Born approximation with and without the internuclear interaction (MCB-NN and MCB) is used to calculate the fully differential cross sections (FDCS) for the single ionization of helium by lOO MeV/amu C6+ impact. The effects of the internuclear interaction on the FDCS are examined in geometries. The results are compared with experimental data and theoretical predictions from a three-body distorted-wave (3DW) model and a time-dependent close-coupling model. It is shown that the present MCB-NN results are in good agreement with the experiments in the scattering plane and the MCB results qualitatively reproduce the experimental structure outside the scattering plane. In particular, the MCB theory predicts the 'double-peak' structure in the perpendicular plane. 展开更多
关键词 MCB NN Nucleus-Nucleus effects in Fully Differential cross Sections for Energetic C He Collisions with Small Momentum Transfer
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Effects of walk-off on cross-phase modulation induced modulation instability in an optical fibre with high-order dispersion 被引量:1
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作者 钟先琼 向安平 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第6期1683-1688,共6页
This paper investigates the effects of walk-off among optical pulses on cross-phase modulation induced modulation instability in the normal dispersion region of an optical fibre with high-order dispersion. The results... This paper investigates the effects of walk-off among optical pulses on cross-phase modulation induced modulation instability in the normal dispersion region of an optical fibre with high-order dispersion. The results indicate that, in the case of high-order dispersion, the walk-off effect takes on new characteristics and will influence considerably the shape, position and especially the number of the spectral regions of the gain spectra of modulation instability. Not only the group-velocity mismatch, but also the difference of the third-order dispersion of two optical waves will alter the gain spectra of modulation instability but in different ways. Depending on the values of the walk-off parameters, the number of the spectral regions may increase from two to at most four, and the spectral shape and position may change too. 展开更多
关键词 modulation instability cross-phase modulation walk-off effect the difference ofthe third-order dispersion
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Interference effects on the photoionization cross sections between two neighbouring atoms:nitrogen as an example
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作者 吴建华 袁建民 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第12期5283-5290,共8页
Interference effects on the photoionization cross sections between two neighbouring atoms are considered based on the coherent scattering of the ionized electrons by the two nuclei when their separation is less than o... Interference effects on the photoionization cross sections between two neighbouring atoms are considered based on the coherent scattering of the ionized electrons by the two nuclei when their separation is less than or comparable to the de Broglie wave length of the ionized electrons. As an example, the single atomic nitrogen ionization cross section and the total cross sections of two nitrogen atoms with coherently added photoionization amplitudes are calculated from the threshold to about А (1 А=0.1 nm) of the photon energy. The photoionization cross sections of atomic nitrogen are obtained by using the close-coupling R-matrix method. In the calculation 19 states are included. The ionization energy of the atomic nitrogen and the photoionization cross sections agree well with the experimental results. Based on the R-matrix results of atomic nitrogen, the interference effects between two neighbouring nitrogen atoms are obtained. It is shown that the interference effects are considerable when electrons are ionized just above the threshold, even for the separations between the two atoms are larger than two times of the bond length of N2 molecules. Therefore, in hot and dense samples, effects caused by the coherent interference between the neighbours are expected to be observable for the total photoionization cross sections. 展开更多
关键词 interference effect photoionization cross section nitrogen atom
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EFFECTS OF SLOPING BOTTOM ON THE DEEPCROSS-EQUATORIAL BOUNDARY CURRENT
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作者 吴德星 吕红民 +1 位作者 郭群 卢镇 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1997年第1期65-69,共5页
This paper reports study focusing on the effects of sloping bottom on the deep cross-equatorial boundary current, and discusses model and laboratory experiment results showing that the southward that the southward int... This paper reports study focusing on the effects of sloping bottom on the deep cross-equatorial boundary current, and discusses model and laboratory experiment results showing that the southward that the southward intrusion distance and flow speed of the western boundary current depend on the bottom slope variation rate,the difference between and and are the current thickness at eastward edge and westward edge, respectively), and the net mass transport. 展开更多
关键词 deep cross-equatorial BOUNDARY current effectS of sloping BOTTOM laboratory TURNTABLE experiment
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Photoemission cross section:A critical parameter in the impurity photovoltaic effect
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作者 Jiren Yuan Haibin Huang +4 位作者 Xinhua Deng Zhihao Yue Yuping He Naigen Zhou Lang Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期552-556,共5页
A numerical study has been conducted to explore the role of photoemission cross sections in the impurity photovoltaic(IPV) effect for silicon solar cells doped with indium. The photovoltaic parameters(short-circuit... A numerical study has been conducted to explore the role of photoemission cross sections in the impurity photovoltaic(IPV) effect for silicon solar cells doped with indium. The photovoltaic parameters(short-circuit current density, opencircuit voltage, and conversion efficiency) of the IPV solar cell were calculated as functions of variable electron and hole photoemission cross sections. The presented results show that the electron and hole photoemission cross sections play critical roles in the IPV effect. When the electron photoemission cross section is 10^-20cm^2, the conversion efficiencyη of the IPV cell always has a negative gain(△η 0) if the IPV impurity is introduced. A large hole photoemission cross section can adversely impact IPV solar cell performance. The combination of a small hole photoemission cross section and a large electron photoemission cross section can achieve higher conversion efficiency for the IPV solar cell since a large electron photoemission cross section can enhance the necessary electron transition from the impurity level to the conduction band and a small hole photoemission cross section can reduce the needless sub-bandgap absorption. It is concluded that those impurities with small(large) hole photoemission cross section and large(small) electron photoemission cross section,whose energy levels are near the valence(or conduction) band edge, may be suitable for use in IPV solar cells. These results may help in judging whether or not an impurity is appropriate for use in IPV solar cells according to its electron and hole photoemission cross sections. 展开更多
关键词 solar cell impurity photovoltaic effect photoemission cross section conversion efficiency
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Changes in brain activation patterns according to cross-training effect in serial reaction time task An functional MRI study
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作者 Yong Hyun Kwon Jung Won Kwon Ji Won Park 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第7期639-646,共8页
Cross-training is a phenomenon related to motor learning, where motor performance of the untrained limb shows improvement in strength and skill execution following unilateral training of the homologous contralateral l... Cross-training is a phenomenon related to motor learning, where motor performance of the untrained limb shows improvement in strength and skill execution following unilateral training of the homologous contralateral limb. We used functional MRI to investigate whether motor performance of the untrained limb could be improved using a serial reaction time task according to motor sequential learning of the trained limb, and whether these skill acquisitions led to changes in brain activation patterns. We recruited 20 right-handed healthy subjects, who were randomly allocated into training and control groups. The training group was trained in performance of a serial reaction time task using their non-dominant left hand, 40 minutes per day, for 10 days, over a period of 2 weeks. The control group did not receive training. Measurements of response time and percentile of response accuracy were performed twice during pre- and post-training, while brain functional MRI was scanned during performance of the serial reaction time task using the untrained right hand. In the training group, prominent changes in response time and percentile of response accuracy were observed in both the untrained right hand and the trained left hand between pre- and post-training. The control group showed no significant changes in the untrained hand between pre- and post-training. In the training group, the activated volume of the cortical areas related to motor function (i.e., primary motor cortex, premotor area, posterior parietal cortex) showed a gradual decrease, and enhanced cerebellar activation of the vermis and the newly activated ipsilateral dentate nucleus were observed during performance of the serial reaction time task using the untrained right hand, accompanied by the cross-motor learning effect. However, no significant changes were observed in the control group. Our findings indicate that motor skills learned over the 2-week training using the trained limb were transferred to the opposite homologous limb, and motor skill acquisition of the untrained limb led to changes in brain activation patterns in the cerebral cortex and cerebellum. 展开更多
关键词 neural regeneration neuroimaging cross-training effects motor skill learning cortical activation cerebellar activation serial reaction time task functional MRI response time response accuracy primary motor cortex dentate nucleus VERMIS grants-supported paper photographs-containingpaper NEUROREGENERATION
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A Facile Photo-cross-linking Method for Polymer Gate Dielectrics and Their Applications in Fully Solution Processed Low Voltage Organic Field-effect Transistors on Plastic Substrate 被引量:1
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作者 Ying Liu Jia-Qing Zhao +4 位作者 Wen-Jian Sun Yu-Kun Huang Su-Jie Chen Xiao-Jun Guo Qing Zhang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第8期918-924,共7页
A simple and effective photochemical method was developed for cross-linking of polymer gate dielectrics. Laborious synthetic processes for functionalizing polymer dielectrics with photo-cross-linkable groups were avoi... A simple and effective photochemical method was developed for cross-linking of polymer gate dielectrics. Laborious synthetic processes for functionalizing polymer dielectrics with photo-cross-linkable groups were avoided. The photo-cross-linker, BBP-4, was added into host polymers by simple solution blending process, which was capable of abstracting hydrogen atoms from polymers containing active C--H groups upon exposure to ultraviolet (UV) radiation. The cross-linking can be completed with a relatively long wavelength UV light (365 nm). The approach has been applied to methacrylate and styrenic polymers such as commercial poly(methylmethacrylate) (PMMA), poly(iso-butylmethacrylate) (PiBMA) and poly(4-methylstyrene) (PMS). The cross-linked networks enhanced dielectric properties and solvent resistance of the thin films. The bottom-gate organic field-effect transistors (OFETs) through all solution processes on plastic substrate were fabricated. The OFET devices showed low voltage operation and steep subthreshold swing at relatively small gate dielectric capacitance. 展开更多
关键词 Organic field-effect transistors Solution processed Polymer dielectric cross-linking PHOTOCHEMISTRY
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Nonlinear spectral cleaning effect in cross-polarized wave generation
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作者 Linpeng Yu Yi Xu +5 位作者 Fenxiang Wu Xiaojun Yang Zongxin Zhang Yuanfeng Wu Yuxin Leng Zhizhan Xu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期281-286,共6页
The underlying mechanism of the spectral cleaning effect of the cross-polarized wave(XPW) generation process was theoretically investigated. This study shows that the spectral noise of an input spectrum can be remov... The underlying mechanism of the spectral cleaning effect of the cross-polarized wave(XPW) generation process was theoretically investigated. This study shows that the spectral noise of an input spectrum can be removed in the XPW generation process and that the spectral cleaning effect depends on the characteristics of the input pulses, such as the chirp and Fourier-transform-limited duration of the initial pulse, and the modulation amplitude and frequency of the spectral noise. Though these factors codetermine the output spectrum of the XPW generation process, the spectral cleaning effect is mainly affected by the initial pulse chirp. The smoothing of the spectrum in the XPW generation process leads to a significant enhancement of the coherent contrast. 展开更多
关键词 nonlinear optics cross-polarized wave generation spectral cleaning effect
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双边市场网约车平台聚合策略选择研究 被引量:2
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作者 曹裕 李想 李青松 《中国管理科学》 北大核心 2025年第4期142-153,共12页
以网约车双边市场为背景,结合双边市场理论以及Hotelling模型构建双寡头平台竞争模型,分析一个由聚合平台中的小平台集合(A)与一个大平台(B)的竞争均衡,研究不同网络外部性强度与用户旅行成本的大平台聚合策略选择问题。理论推导了不聚... 以网约车双边市场为背景,结合双边市场理论以及Hotelling模型构建双寡头平台竞争模型,分析一个由聚合平台中的小平台集合(A)与一个大平台(B)的竞争均衡,研究不同网络外部性强度与用户旅行成本的大平台聚合策略选择问题。理论推导了不聚合策略(N)、跟随策略(F)与开放策略(O)下的双边市场规模决策、定价决策以及定价对用户转移的影响。进一步,通过数值模拟比较不同聚合策略下的大平台利润,发现交叉网络外部性与用户旅行成本是影响大平台聚合策略选择的重要因素。当用户端和司机端交叉网络外部性均低时,大平台不参与聚合,随着外部性上升,其选择会从跟随策略转变为开放策略,其中用户端网络外部性对跟随策略、司机端网络外部性对开放策略作用更为显著;当用户旅行成本低于阈值时,大平台采取跟随策略,否则不参与聚合。有趣的是,司机旅行成本和聚合平台抽成比例均不会影响大平台聚合策略选择,可为现实中聚合平台前期的免抽成策略做出解释。 展开更多
关键词 双边市场 网约车平台 聚合策略 交叉网络外部性
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基于改进前馈自抗扰的SIDO Boost变换器复合控制 被引量:1
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作者 皇金锋 李聪林 陈旭 《华中科技大学学报(自然科学版)》 北大核心 2025年第1期48-55,共8页
为提升SIDO Boost变换器的暂态性能和稳定性,提出了一种基于改进前馈自抗扰控制器的复合控制策略.首先,针对该变换器存在非最小相位影响,结合该变换器可降压的特性,利用输出重定义法,设计了a支路双环控制降压输出,b支路单环控制升压输... 为提升SIDO Boost变换器的暂态性能和稳定性,提出了一种基于改进前馈自抗扰控制器的复合控制策略.首先,针对该变换器存在非最小相位影响,结合该变换器可降压的特性,利用输出重定义法,设计了a支路双环控制降压输出,b支路单环控制升压输出的总体控制策略;然后,针对交叉耦合影响和扰动问题提出了改进前馈自抗扰控制器,引入了负载前馈误差信号,增加系统抗扰性,加快响应速度;同时设计了改进扩张状态观测器,来提高观测精度和响应速度,并改进自适应超螺旋滑模反馈控制律的不连续函数来进一步抑制系统抖振;接着,利用李雅普洛夫理论证明了反馈控制律的稳定性;最后,利用实验平台进行了实验,实验结果验证了所提控制策略的有效性和优越性. 展开更多
关键词 SIDO Boost变换器 非最小相位特性 交叉耦合影响 前馈自抗扰控制 李雅普洛夫理论
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中国个人所得税收入调节分组效应研究
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作者 胡华 李冬妍 《经济科学》 北大核心 2025年第3期71-90,共20页
已有研究将MT指数分解为各边际税率与税前扣除的分效应,本文将上述分效应再次分解为组内、组间与跨组效应。2019年我国进行个人所得税方面的税制改革,相对于旧税制,新税制有六项新内容:税级距变更、免征额提升、增设七项专项附加扣除、... 已有研究将MT指数分解为各边际税率与税前扣除的分效应,本文将上述分效应再次分解为组内、组间与跨组效应。2019年我国进行个人所得税方面的税制改革,相对于旧税制,新税制有六项新内容:税级距变更、免征额提升、增设七项专项附加扣除、计税周期变更、2018年的年终奖个人所得税征收改革、2028年的年终奖个人所得税征收改革。本文发现,前四项内容会削弱个人所得税的收入调节效应,后两项内容则会增强个人所得税的收入调节效应。基于十种人口异质性,本文将家庭样本数据分组,计算各边际税率与税前扣除的组内、组间与跨组效应,发现各类要素的组内效应占总效应的比重多处于50%-150%。这表明:人口异质性对个人所得税收入调节功能产生了“隔离效应”,将此功能限制在了组内样本中。 展开更多
关键词 个人所得税 组内效应 组间效应 跨组效应
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Adaptive Random Effects/Coefficients Modeling
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作者 George J. Knafl 《Open Journal of Statistics》 2024年第2期179-206,共28页
Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using general... Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using generalized linear models in fixed effects/coefficients. Correlations are modeled using random effects/coefficients. Nonlinearity is addressed using power transforms of primary (untransformed) predictors. Parameter estimation is based on extended linear mixed modeling generalizing both generalized estimating equations and linear mixed modeling. Models are evaluated using likelihood cross-validation (LCV) scores and are generated adaptively using a heuristic search controlled by LCV scores. Cases covered include linear, Poisson, logistic, exponential, and discrete regression of correlated continuous, count/rate, dichotomous, positive continuous, and discrete numeric outcomes treated as normally, Poisson, Bernoulli, exponentially, and discrete numerically distributed, respectively. Example analyses are also generated for these five cases to compare adaptive random effects/coefficients modeling of correlated outcomes to previously developed adaptive modeling based on directly specified covariance structures. Adaptive random effects/coefficients modeling substantially outperforms direct covariance modeling in the linear, exponential, and discrete regression example analyses. It generates equivalent results in the logistic regression example analyses and it is substantially outperformed in the Poisson regression case. Random effects/coefficients modeling of correlated outcomes can provide substantial improvements in model selection compared to directly specified covariance modeling. However, directly specified covariance modeling can generate competitive or substantially better results in some cases while usually requiring less computation time. 展开更多
关键词 Adaptive Regression Correlated Outcomes Extended Linear Mixed Modeling Fractional Polynomials Likelihood cross-Validation Random effects/Coefficients
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Selection Effects of Soil Fertility on the Progenies of Soybean Crosses
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作者 Zou Jijun, Yang Qingkai, Wang Jiming(Northeast Agricultural University, Harbin 150030, PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1996年第2期88-93,共6页
The F2, F3, families and F4 lines of six soybean crosses, were selected successively under high-and low - fertility sites with the relection objective of high yield and the method of pedigree was used. Two best F4 - d... The F2, F3, families and F4 lines of six soybean crosses, were selected successively under high-and low - fertility sites with the relection objective of high yield and the method of pedigree was used. Two best F4 - derived lines were chosen from each of the six crosses under both high-and low-fertility for use in this study. In 1995, the total 24 lines were tested in high, medium and low fertility sites with the same experimental design (CRB) to study the selcctoin effects of high and low - fertility. The results suggested that high- and low-fertility had different selection effects. High fertility was more effective for selecting lines, which had higher yield under high-fertility and lower yield under low-fertility; low-fertility was better for selecting lines, which had higher yield under low-fertility and lower yield under low-fertility, and high fertility was somewhat better than low fertility for selecting lines, which had higher yield under both high and low-fertility. It revealed that the lines selected from high-fertility had superior yield potential. The lines selected from high-fertility had shorter plant height, more nodes on main stem, fewer branches, higher seed-stem ratio. The reverse was true for the lines selected from low-fertility . The lodging-resistance of the lines selected from highfertility was greater than that of the lines from low-fertility. The soil fertility level of breeding nursery should be chosen according to the breeding objective. 展开更多
关键词 progenics or soybean crosses soil fertility selection effects
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Dynamic nuclear polarization and chemically induced hyperpolarization:Progress,mechanisms,and opportunities
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作者 Danhua Dai Yangping Liu +1 位作者 Xiao He Jiafei Mao 《Magnetic Resonance Letters》 2025年第3期23-49,共27页
Nuclear magnetic resonance(NMR)spectroscopy is a powerful and broadly used spectroscopic technique for characterizing molecular structures and dynamics.Yet the power of NMR is restricted by its inherently low sensitiv... Nuclear magnetic resonance(NMR)spectroscopy is a powerful and broadly used spectroscopic technique for characterizing molecular structures and dynamics.Yet the power of NMR is restricted by its inherently low sensitivity due to the weak polarization of nuclear spins under conventional experiment conditions.Dynamic nuclear polarization(DNP)and chemically induced dynamic nuclear polarization(CIDNP)have been emerging as powerful in-situ hyperpolarization methods to boost NMR sensitivity.This review provides a brief overview of DNP mechanisms in the context of both solid-state and liquidstate.We delve into the molecular features of different polarizing agents and their impacts on DNP applications,which are now steadily progressing towards modern NMR magnetic field strengths and ambient temperatures.Furthermore,the progress of CIDNP,particularly photo-CIDNP as a potential alternative hyperpolarization technique of DNP,in studying protein dynamics and chemical reaction mechanisms,will be covered.This review also highlights the chemical diversity and experimental strategies crucial for these hyperpolarization techniques,showcasing their transformative role in NMR spectroscopy. 展开更多
关键词 Dynamic nuclear polarization(DNP) NMR spectroscopy Chemically induced dynamic nuclear polarization(CIDNP) RADICAL cross effect Solid effect Overhauser effect
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花下刺:中国网络文学跨文化传播效果研究——基于Reddit评论区文本的分析 被引量:1
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作者 田丽 满运玖 《出版科学》 北大核心 2025年第3期96-107,共12页
采用定性与定量相结合的研究方法深入分析中国网络文学跨文化传播的效果。研究发现,翻译困扰和认知层次是影响海外读者接受中国网络文学的重要影响因素,海外读者往往被网文中的外在文化符号吸引但对其中大众文化的草根特性深刻拒斥,对... 采用定性与定量相结合的研究方法深入分析中国网络文学跨文化传播的效果。研究发现,翻译困扰和认知层次是影响海外读者接受中国网络文学的重要影响因素,海外读者往往被网文中的外在文化符号吸引但对其中大众文化的草根特性深刻拒斥,对深层文化价值则视而不见,即中国网络文学在跨文化传播中存在“形”与“质”的割裂。建议提升网络文学翻译的质量,注重文化适应性,提升创作者的跨文化传播自觉性,展现中国文化的多元面貌。 展开更多
关键词 数字出版 网络文学 跨文化传播 出海 传播效果
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数字金融对环境污染治理的影响及空间溢出效应研究
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作者 胡宗义 刘俊娇 李毅 《生态经济》 北大核心 2025年第11期180-189,共10页
数字金融打破了传统金融服务的空间限制,为解决环境污染跨区域问题提供了新思路。论文以2011—2022年中国284个地级及以上城市为研究样本对数字金融的环境治理效应进行了实证检验。研究发现,数字金融发展能够显著抑制环境污染,并且存在... 数字金融打破了传统金融服务的空间限制,为解决环境污染跨区域问题提供了新思路。论文以2011—2022年中国284个地级及以上城市为研究样本对数字金融的环境治理效应进行了实证检验。研究发现,数字金融发展能够显著抑制环境污染,并且存在显著的空间溢出效应。通过对比不同空间权重矩阵下的实证结果可以发现,数字金融的空间溢出效应更多得益于现代经济发展而非传统地理因素的作用,经济关联成为实现环境污染跨区治理的关键因素;机制检验表明,数字金融发展能够通过推动城市产业结构升级和区域绿色技术创新缓解城市环境污染问题,并且数字金融的发展带动了金融资源跨区流动以及绿色技术扩散,推动了周边地区环境状况的改善;异质性结果表明,数字金融对环境污染的空间溢出效应在经济发展水平较低、国家级大数据综合试验区以及资源型城市中表现更为显著,数据要素成为跨区环境污染协同治理的关键驱动。 展开更多
关键词 数字金融 环境污染 空间溢出效应 资源跨区流动 绿色技术扩散
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绩效敞视与跨界协同:数字平台治理的监管逻辑 被引量:1
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作者 杨宏山 杨哲盈 《江苏行政学院学报》 北大核心 2025年第3期110-119,共10页
现代政府治理通过构建数字平台,在多方主体之间增进互动,以问题为触发机制而快速启动处置流程,促使公共部门提升回应性。本研究从行动网络的视角,提出“绩效敞视—跨界协同”分析框架,解释数字平台治理的监管逻辑。数字平台宛若政府运... 现代政府治理通过构建数字平台,在多方主体之间增进互动,以问题为触发机制而快速启动处置流程,促使公共部门提升回应性。本研究从行动网络的视角,提出“绩效敞视—跨界协同”分析框架,解释数字平台治理的监管逻辑。数字平台宛若政府运行的神经中枢,它依靠技术赋能发展出一套灵活的组织体系,在多元主体之间增进互动,通过汇聚平台数据进行部门绩效评价,进而产生绩效敞视效应。运用绩效信息进行跨界监管,有利于促进跨层级、跨部门、跨系统协同。北京市“接诉即办”平台的运作实践,证明了绩效敞视增强了公职人员的成就动机和责任心,促进了跨界协同。基于数字平台的跨界监管也可能产生“内卷化”现象而增加基层负担,为此,需要通过反馈学习改进机制设计。 展开更多
关键词 数字平台治理 跨界监管 权威整合 绩效敞视效应
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Water equivalence of some 3D dosimeters:a theoretical study based on the effective atomic number and effective fast neutron removal cross section
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作者 A.M.El-Khayatt 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第12期170-181,共12页
Effective atomic numbers for photon energy absorption(ZPEA_(eff)) and their corresponding electron numbers (NPEA_(eff)), and effective macroscopic removal cross sections of fast neutrons(RR) were calculated for 27 dif... Effective atomic numbers for photon energy absorption(ZPEA_(eff)) and their corresponding electron numbers (NPEA_(eff)), and effective macroscopic removal cross sections of fast neutrons(RR) were calculated for 27 different types of three-dimensional dosimeters, four types of phantom materials, and water. The values of ZPEA_(eff) and NPEA_(eff) were obtained using the direct method for energies ranging from 10 keV to 20 MeV. Results are presented relative to water, for direct comparison over the range of examined energies. The effect of monomers that are used in polymer gel dosimeters on the water equivalence is discussed. The relation between Σ_R and hydrogen content was studied. Micelle gel dosimeters are highly promising because our results demonstrate perfect matching between the effective atomic number, electron density number, and fast neutron attenuation coefficient of water. 展开更多
关键词 3D DOSIMETERS WATER EQUIVALENCE effectIVE atomic number Photon energy absorption REMOVAL cross section Fast neutrons
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