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Influence of light on the chroma of low pressure hydrogenation aviation kerosene was studied using different lights (ultraviolet light, infrared light, sunlight and no light) in the same environment full of oxygen. UV light with short wavelength has the largest influence. Coloring substances were isolated by adsorption on neutral alumina followed by ether extraction and identified by using infrared spectrum, elemental analysis and two-dimensional GC-MS. Oxygen-containing compounds are main coloring substances. Light can provide the required energy to convert unsaturated hydrocarbons and heteroatom compounds to phenols, quinones and ketones. [ABSTRACT FROM AUTHOR]

This article focuses on the two sample test of the survival function of the failure time under the current status data and introduces three types of the non-parametric two sample test of the survival function. This paper constructs the empirical likelihood ratio test with a weighted approach for the two sample comparison based on MLE, SMLE, and MSLE. A bootstrap method is given for constructing the null hypothesis distribution and determining p-value. In simulation studies, we examine the finite-sample performance of the proposed approach and compare it with an existing method. [ABSTRACT FROM AUTHOR]

Two new 3-D lanthanide coordination polymers, [CeK(btec)(H2O)2] n (1), [Ho(btec)0.5(ad)0.5(H2O)] n (2) (H4btec = 1,2,4,5-benzenetetracarboxylic acid, H2ad = adipic acid), have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. Structural analyses reveal that both complexes crystallized in monoclinic space group P21/c and possessed 3-D net-structures. In 1, btec adopts two types of coordination modes: µ12–η2:η2:η2:η1:η2:η2:η2:η1 bridging mode linking six Ce(III) ions and six K+ ions and the other µ8–η1:η2:η2:η1:η1:η2:η2:η1 bridging mode connecting four Ce(III) ions and four K+ ions. In 2, btec adopts a µ6-bridging with each carboxylate group of btec ligand in a µ2–η1–η2 mode, the adipate is µ4-bridging with each carboxylate µ2–η1–η1-monodentate. The topological analysis shows that 1 can be simplified to a 3-nodal net with the Schläfli symbol {32,48,53,62}4{34,412,512}{438,626,82} and 2 can be simplified to a 3-nodal network with the Schläfli symbol {42,84}{46,66,83}{47,63}2. The thermogravimetric analyses and the X-ray powder diffraction of 1 and 2 are discussed. [ABSTRACT FROM AUTHOR]

The Photovoltaic industry promotes the transformation of China's energy structure to green and low-carbon, which is of great significance to achieve the goal of "Carbon Peaking and Carbon Neutrality." At present, the industry is mainly faced with problems such as the drastic reduction of government subsidies and the difficulty of financing. From the perspective of independent auditing, our paper takes 54 A-share listed photovoltaic companies in China from 2011 to 2020 as the research object to study the impact of audit quality on financing efficiency, and the role of agency costs in the relationship between audit quality and financing efficiency.The results show that audit quality is positively related to financing efficiency. For every 1% increase in audit quality, the financing efficiency will increase by 13%. In addition, agency cost plays an intermediary role between audit quality and financing efficiency. For every 1% increase in audit quality, agency cost can be reduced by 34% and financing efficiency can be increased by 25%. [ABSTRACT FROM AUTHOR]

Voluminous Neoproterozoic granitoid sheets of the Imorona–Itsindro Suite are important components of exposed basement in west-central Madagascar. Here, we report precise new zircon U–Pb ages and whole-rock geochemistry for granitoids within the Maevatanana area of Madagascar. The new laser ablation inductively coupled plasma mass spectrometry zircon U–Pb dating undertaken during this study indicates that Antanimbary granitoid and Antasakoamamy granitoid were emplaced at 747 ± 9 Ma and 729 ± 9–727 ± 8 Ma, respectively. Geochemically, the Antanimbary granitoids show poor Nb, Ta anomalies, pronounced positive Zr anomalies, and are K-rich (K2O/Na2O > 1), but the Antasakoamamy granitoids are relatively depleted in Nb, Ta, show slightly negative Zr anomalies, and are Na-rich (Na2O/K2O > 1). Both suites contain zircons with strongly negativeεHf(t), indicating participation of much older (Palaeoproterozoic and Archaean) crust. Their geochemical characteristics, along with the use of various discrimination diagrams, reveals that crustal delamination and asthenospheric upwelling resulted in crustal extension of the region before ~747 Ma, with subsequent lithospheric subduction and arc magmatism after 729–727 Ma. [ABSTRACT FROM AUTHOR]