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1.
为研究新疆地区税制结构以及非税收入对经济增长的影响,建立了包含税收结构与非税收入的内生增长理论模型,并依据新疆1994~2018年度政府税收收入、非税收入以及地区生产总值(GDP)的数据构建了向量自回归模型(VAR),通过脉冲响应分析和方差分解分析研究了各变量的显著性和动态效应.研究结果表明:新疆地区资本税总体上有利于经济增长,劳动税对经济增长有抑制作用,消费税有略微负向影响,非税收入长期内不利于经济增长.因此新疆地方政府应该加强所得税相关政策实施监管,注重制造业发展困境,并加大非税收入的管理公开度. 相似文献
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For this study, we synthesized Aurivillius Bi5Ti3FeO15 ceramic using the generic solid-state reaction route and then performed room-temperature X-ray diffraction to confirm that the compound had a single phase with no impurities. The surface morphology of the prepared sample was observed to contain microstructural grains approximately 0.2–2 μm in size. The dielectric properties of the sample were determ-ined as a function of frequency in a range of approximately 100 Hz to 1 MHz at various temperatures (303 K ≤ T ≤ 773 K). Nyquist plots of the impedance data were found to exhibit a semi-circular arc in the high-temperature region, which is explained by the equivalent electrical circuit (R1C1)(R2QC2), where R1 and R2 represent the resistances associated with the grains and grain boundaries, respectively, C1 and C2 are the re-spective capacitances, and Q is the constant phase element (CPE), which accounts for non-Debye type of behavior. Our results indicate that both the resistance and capacitance of the grain boundaries are more prominent than those of the grains. The alternating current (ac) conductiv-ity data were analyzed based on the Jonscher universal power law, which indicated that the conduction process is dominated by the hopping mechanism. The calculated activation energies of the relaxation and conduction processes were very similar (0.32 to 0.53 eV), from which we conclude that the same type of charge carriers are involved in both processes. 相似文献
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Cobalt (Co)-modified brownmillerite KBiFe2O5 (KBFO; [KBiFe2(1?x)Co2xO5 (x = 0, 0.05)]) polycrystalline is synthesized following the solid-state reaction route. Rietveld refinement of X-ray diffraction data confirmed the phase purity of KBFO and KBiFe1.9Co0.1O5 (KBFCO). The optical bandgap energy (Eg) of KBFO decreased from 1.59 to 1.51 eV because of Co substitution. The decrease in bandgap can be attributed to the tilting of the Fe–O tetrahedral structure of KBFCO. The observed room-temperature Raman peaks of KBFCO shifted by 3 cm?1 toward a lower wavenumber than that of KBFO. The shift in Raman active modes can be attributed to the change in the bond angles and bond lengths of the Fe–O tetrahedral structure and modification in response to oxygen deficiency in KBFO because of Co doping. Compared with that of KBFO, the frequency-dependent dielectric constant and dielectric loss of KBFCO decrease at room temperature, which is a con-sequence of the reduction in oxygen migration and modification in response to vibrational modes present in the sample. 相似文献
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The effect of cold rolling and post-rolling heat treatment on the microstructural and electrochemical properties of the 316L stainless steel was investigated.Two-pass and four-pass cold-rolled stainless steel specimens were heat-treated by annealing at 900℃followed by quenching in water.During the cold rolling,the microstructure of the as-received specimen transformed from austenite to strain-inducedα′-martensite due to significant plastic deformation that also resulted in significant grain elongation(i.e.,~33%and 223%increases in the grain elongation after two and four rolling passes,respectively).The hardness of the heat-treated as-received specimen decreased from HV 190 to 146 due to the recovery and recrystallization of the austenite grain structure.The cyclic polarization scans of the as-rolled and heat-treated specimens were obtained in 0.9wt%NaCl solution.The pitting potential of the four-pass rolled specimen was significantly increased from 322.3 to 930.5 mV after post-rolling heat treatment.The beneficial effect of the heat treatment process was evident from~10-times-lower corrosion current density and two-orders-of-magnitude-lower passive current density of the heat-treated specimens compared with those of the as-rolled specimens.Similarly,appreciably lower corrosion rate(3.302×10?4mm/a)and higher pitting resistance(1115.5 mV)were exhibited by the postrolled heat-treated specimens compared with the as-rolled 316L stainless steel specimens. 相似文献
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正这本书将成为霍金的宣言。它乐观、富有远见,认为科学和对科学的理解对人类未来至关重要。出版商通常迫切希望他们的新书得到评论,一旦标题推出,他们就会用不请自来的出版样本去轰炸报纸、网站和杂志,以获得更多的报道。看看《物理世界》的档案柜:里面满是我们不想要的书,都是由渴望得到宣传的出版商寄来的。然而,对史蒂芬·霍金的最新一本、也是最后一本著作来说,却发生了一些非常不同的事情。《大问题简答》今日发布,为了先一睹为快,《物理世界》 相似文献
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新型的知识载体和交流平台日新月异,对多样化成果评价方式的需求迫在眉睫。Altmetrics为测量研究成果影响力提供了新的视角,拓展了人们对学术影响力的认知广度和深度,是传统计量学的深度发展。该研究通过文献调研与内容分析法,对Altmetrics的国内外发展趋势、研究内容与创新应用进行了综述分析。结果表明:Altmetrics为科研成果影响力评价提供了新的方法、指标和工具集,其应用越来越广泛,引起了学术界的高度关注;图书馆作为科学交流的重要组成部分,必将卷入革新的浪潮。 相似文献
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为了快速有效地提取视频中含有维吾尔文字幕的关键帧提出一种新方法.该方法首先运用多尺度Harris角点检测,结合维吾尔文字笔画特点,完成字幕关键帧的初步提取;然后利用最小二乘法拟合直线,根据两条拟合直线的角度偏离情况对初步提取的结果作去冗余处理,得到最终字幕关键帧.实验结果表明:该方法快速简单,提取结果的准确率达到93%,具有很好的适应性. 相似文献
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