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增值税抵扣权与发票制度:形式课税原则之改进
Get PDF抵扣权是增值税设计及立法的核心,欧盟及主要国家法院强调抵扣权在价值上优先于发票控税,且不能以发票限制这一基本权利。通过分析主要国家的司法判例及其立场转变,本文建议我国增值税立法应引入\"抵扣权\"概念,并从确立权利行使的实质重于形式原则、引入扩大化的\"发票\"概念、立法建构类型化的特殊抵扣制度、推动整体税制及征管制度的改革四个方面促进增值税抵扣权行使的制度改进
二战之后国际经济秩序公正性之评判——基本逻辑、实力兴衰及收益变化
Get PDF对于二战之后建立的自由主义国际经济秩序之公正性问题的研究,围绕\"实力界定收益\"基本逻辑这一主线,以往中国学界实际上作出的多为静态的分析。应该说,这样的分析是不完整的。唯有在此之上增添动态的视角——以各国实力兴衰与收益变化及二者之间的联动关系为基准,才能判定从往至今发展中国家对自由主义国际经济秩序以及现今特朗普执政下的美国对其中自由主义国际贸易体制之公正性问题认知的真伪。2009年教育部哲学社会科学研究重大课题攻关项目“全球金融危机后国际经济秩序重构与中国的法律对策研究”(项目批准号:09JZD0021
石墨烯改性PDC-SiCNO陶瓷的制备及其介电性能
No full text以聚乙烯基硅氮烷(PVSZ)为原料,氧化石墨烯(GO)为碳源,无水乙醇(ETOH)为分散剂,制备石墨烯球增强SiCNO陶瓷(SiCNO-GO)。利用拉曼光谱(Raman)、电子自旋共振(EPR)和扫描电子显微镜(SEM)等表征手段,研究SiCNO-GO陶瓷结构对其介电性能的影响。结果表明:SiCNO-GO陶瓷的微球密度和粒径的大小与GO的含量有关;随着SiCNO-GO陶瓷中GO含量的增加,SiCNO-GO陶瓷的介电常数和介电损耗也随之增大,在GO含量为0.1%(质量分数)时达到最大值,而当GO质量分数为0.3%时,SiCNO-GO陶瓷的介电常数和介电损耗降低。国家自然科学基金项目(51675452);;装备预研基金项目(6140923020301);;反应堆燃料及材料重点实验室基金(6142A0604030817
A nickel pyridine-selenolate complex for the photocatalytic evolution of hydrogen from aqueous solutions
Get PDFAbstract(#br)A nickel pyridine-selenolate complex, [Ni(4,4′-dmbpy)(2-pySe) 2 ] ( 1 , where 4,4′-dmbpy = 4,4′-dimethyl-2,2′-bipyridine, and 2-pySe = pyridine-2-selenolate), has been synthesized, and investigated for photocatalytic production of H 2 from aqueous solution. Electrochemical studies show that the nickel complex 1 can efficiently electrocatalyze H 2 evolution from weakly acidic solutions. Under visible-light irradiation (λ > 420 nm), the complex 1 displays impressive H 2 evolution activity with a TON of 1340 (based on a catalyst) in a noble-metal-free system, which contains fluorescein (Fl) as photosensitizer and triethylamine (TEA) as sacrificial electron donor in acetonitrile-water solution. It should be noted that complex 1 is the rare example of nickel pyridine-selenolate complex as molecular photocatalyst for water reduction
磷掺杂中空碳球的制备及其电容性能研究
Get PDF以酚醛预聚体和苯乙烯为原料通过水热法一步合成中空聚合物球HPS，再以三氯化磷为反应剂通过傅-克反应对HPS处理得到含磷交联聚合物，经高温碳化和KOH活化制备了磷掺杂中空碳球AP-HCS。采用FT-IR、TG、SEM、TEM、Raman、BET、XPS等手段对含磷聚合物和碳材料的组成、结构与形貌进行表征，测试了碳材料在1mol/L H2SO4介质中的电容性能。结果表明，AP-HCS的比表面积可达2177m2/g，在1A/ g电流密度下，比电容为288F/g，5A/g电流密度下经循环充放电5000次后比电容值仍能保持88.9%，具备良好的电容性能。国家自然科学基金项目(51673161,51773172)福建省重大科技创新平台(2014H2006
Ultra-High Performance of Hyper-Crosslinked Phosphate-Based Polymer for Uranium and Rare Earth Element Adsorption in Aqueous Solution.
Get PDFIn this work, a new type of hyper-crosslinked phosphate-based polymer (HCPP) polymerized by bis(2-methacryloxyethyl)phosphate has been developed for uranium and rare earth element (REE) extraction in an aqueous solution. The influence of the pH value, contact time, initial concentration, temperature, and competing ions on uranium adsorption of HCPP is investigated in detail. HCPP exhibits a maximum uranium adsorption capacity of up to 800 mg g-1 at pH = 6.0 and excellent selectivity toward uranium adsorption over coexisting ions, because of the high affinity between HCPP and uranium ions and dense phosphate groups on the backbone. It also demonstrates high adsorption performance in both simulated seawater with a high salt concentration and a real nuclear industrial effluent. Besides, the crosslinked network structure of HCPP endows this polymer with high chemical stability and reusability. Furthermore, the adsorption mechanism is probed by energy-dispersive spectroscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared measurements. It is confirmed that the adsorption of uranium on the adsorbent originates from the interaction between phosphate groups and uranium ions. Meanwhile, HCPP also displays high REE adsorption capacities. This work indicates that the phosphate-based HCPP could be utilized as a promising adsorbent for the effective removal of uranium and REEs from aqueous solution
Synergistic photoelectrochemical performance of La-doped RuO 2 -TiO 2 /Ti electrodes
Get PDFAbstract(#br)RuO 2 -TiO 2 /Ti electrodes with low-content La-doping are prepared by thermal decomposition method. The effect of La doping on their electrochemical performance upon UV illumination are investigated. The doped electrodes show higher density of cracks and rugosity in microscale on the surface than the undoped ones. They also have a negative shift of the onset potential of oxygen evolution from 1.1 V to 1.0 V and higher current intensity under UV irradiation as well. Electrochemical impedence spectroscopy analysis demonstrates a better electrical conductivity of the doped film. Electron paramagnetic resonance results show that the obtained La-doped TiO 2 surface provides a higher density of oxygen vacancies. This anode also has 7.5% higher degradation rate of the methylene blue than La-undoped ones under UV irradiation. This is probably due to the increased surface rugosity and better electric conductivity, higher density of oxygen vacancies under UV irradiation by the doping of La ions
Design and Fabrication of High Activity Retention Al-Based Composite Powders for Mild Hydrogen Generation.
Get PDFAl-Bi-Sn-Cu composite powders for hydrogen generation were designed from the calculated phase diagram and prepared by the gas atomization process. The morphologies and structures of the composite powders were investigated using X-ray diffraction (XRD) and a scanning electron microscope (SEM) equipped with energy-dispersive X-ray (EDX) spectroscopy, and the results indicate that the Cu additive enhanced the phase separation between the Al-rich phase and the (Bi, Sn)-rich phase. The hydrogen generation performances were investigated by reacting the materials with distilled water. The Al-Bi-Sn-Cu powders reveal a stable hydrogen generation rate, and the Al-10Bi-7Sn-3Cu (wt%) powder exhibits the best hydrogen generation performance in 50 °C distilled water which reaches 856 mL/g in 800 min. In addition, the antioxidation properties of the powders were also studied. The Al-10Bi-7Sn-3Cu (wt%) powder has a good resistance to oxidation and moisture, which shows great potential for being the hydrogen source for fuel cell applications
Ultrasensitive label-free detection of circulating tumor cells using conductivity matching of two-dimensional semiconductor with cancer cell
Get PDFAbstract(#br)The excellent conductivity matching of two-dimensional (2D) semiconductor nanomaterials (e.g. MoS 2 ) with cancer cell plays an important role in ultrasensitive label-free impedimetric detection of circulating tumor cells (CTC) (<1 cell/mL). Firstly, 2D semiconductor materials (e.g. 2D MoS 2 ) exfoliated by folic acid (FA) is used to construct MoS 2 /FA-modified gold electrode (AuE/MoS 2 /FA). Then, the fabricated electrode is applied for HeLa cell detection in a linear range from 1 to 10 5 cell/mL with a detection limit of 0.43 cell/mL (S/N = 3). The detection mechanism of high sensitivity might be owing to the electric conductivity matching of MoS 2 (0.14 S/m) to cancer cell (0.13–0.23 S/m). A negligible conductivity change induced by cancer cell will produce a large impedance change of semiconductor electrode. Furthermore, HeLa cells dispersed in healthy blood samples are detected by suggested cytosensor in a linear range from 50 to 10 5 cell/mL with a detection limit of 52.24 cell/mL (S/N = 2). Finally, we demonstrate that the cytosensor is capable of differentiating patients of cervical and liver cancers by the real CTC analysis from healthy control
具有光热性能的碳龙配合物材料（英文）
No full text金属有机化合物很少作为光热材料.报道一系列碳龙配合物的合成及其光热性能,将OsCl2（PPh3）3与有机多炔碳链反应获得金属杂戊搭炔,再与末端炔烃发生[2+2]环加成反应得到此类碳龙配合物--锇杂戊搭烯并环丁二烯.这些共轭的金属杂环化合物在紫外-可见区具有宽吸收并表现出优异的光热性能,有望成为一类新型的光热材料.Project supported by the National Natural Science Foundation of China(Nos.21302158,U1705254,21490573)~