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[Display omitted] The merging of transition metal catalysis with electrochemistry has become a powerful tool for organic synthesis because catalysts can govern the reactivity and selectivity. However, coupling catalysts with alkyl radical species generated by anodic oxidation remains challenging because of electrode passivation, dimerization, and overoxidation. In this study, we developed convergent paired electrolysis for the coupling of nickel catalysts with alkyl radicals derived from photoinduced ligand-to-metal charge-transfer of cyclic alcohols and iron catalysts, providing a practical method for site-specific and remote arylation of ketones. The synergistic use of photocatalysis with convergent paired electrolysis can provide alternative avenues for metal-catalyzed radical coupling reactions. [ABSTRACT FROM AUTHOR]

As CO 2 emissions are quantified by allowances and traded in markets, wise trading strategies will bring emitting companies higher profits or lower costs. Based on the big data of Community Independent Transaction Log (CITL), this article hereby presents a micro study on the emitting companies' efforts in increasing profits and saving costs during the allowances trading in the first two phases of the European Union Emission Trading Scheme (EU ETS). The efforts are measured by an after-action factor of trading performance, which is built on a series of behaviour and monetary variables. By comparison, demanders of the emitting companies are more inclined to reach a higher trading performance, while that inclination is heterogeneous among the suppliers. In addition, emitting companies with lower emission levels had a better trading performance. With a higher proportion of low-emitting companies, the manufacturing sector had a better trading performance than the energy sector. The effect of the trading requirement on trading performance are investigated via a quantile regression mode. Results suggest that: (1) the selling requirement of suppliers has a positive effect on their trading performance, while the effect becomes weaker when the selling requirement increases; (2) the buying requirement has a positive effect on the demanders' trading performance only when the requirement is high, and the effect becomes stronger as the requirement increases; and (3) when the buying requirement is at a lower level, demanders' trading performance becomes worse as the requirement grows. The conclusion is that the emission level, industrial sector and trading requirement do have influences on the trading performance of emitting companies in emission trading. [ABSTRACT FROM AUTHOR]

Herein, we have developed a simple, sensitive and paper-based colorimetric sensor for the selective detection of Chromium (Ⅵ) ions (Cr (VI)). Silanization-titanium dioxide modified filter paper (STCP) was used to trap bovine serum albumin capped gold nanoparticles (BSA-Au NPs), leading to the fabrication of BSA-Au NPs decorated membrane (BSA-Au NPs/STCP). The BSA-Au NPs/STCP operated on the principle that BSA-Au NPs anchored on the STCP were gradually etched by Cr (VI) as the leaching process of gold in the presence of hydrobromic acid (HBr) and hence induced a visible color change. Under optimum conditions, the paper-based colorimetric sensor showed clear color change after reaction with Cr (VI) as well as with favorable selectivity to a variety of possible interfering counterparts. The amount-dependent colorimetric response was linearly correlated with the Cr (VI) concentrations ranging from 0.5 µM to 50.0 µM with a detection limit down to 280 nM. Moreover, the developed cost-effective colorimetric sensor has been successfully applied to real environmental samples which demonstrated the potential for field applications. [ABSTRACT FROM AUTHOR]

Human behaviour on the Internet has become a synchro-projection of real society. In this paper, we introduce the public concern derived from query volumes on the Web to empirically analyse the influence of information on commodity markets (e.g., crude oil, heating oil, corn and gold) using multivariate GARCH models based on dynamic conditional correlations. The analysis found that the changes of public concern on the Internet can well depict the changes of market prices, as the former has significant Granger causality effects on market prices. The findings indicate that the information of external shocks to commodity markets could be transmitted quickly, and commodity markets easily absorb the public concern of the information-sensitive traders. Finally, the conditional correlation among commodity prices varies dramatically over time. [ABSTRACT FROM AUTHOR]

Oil-related events have increased the uncertainty and complexity of the worldwide oil market. This paper investigates the effects of four types of oil-related events on world oil prices, using an event study methodology and an AR-GARCH model. The Internet information concerning these events, which is derived from search query volumes in Google, is introduced in an analytical framework to identify the magnitude and significance of the market response to oil-related events. The results indicate that world oil prices responding to different oil-related events display obvious differentiation. The cumulative abnormal returns, which reflect the influence of the global financial crisis, tend to drop first and then reverse and rise, while the cumulative abnormal returns induced by other oil-related events present a stronger persistent effect. The impact of the global financial crisis on oil price returns is significantly negative, while the impact of the Libyan war and hurricanes is significantly positive. However, the reactions of oil price returns to different OPEC production announcements are inconsistent. [ABSTRACT FROM AUTHOR]

As a typical semiconductor, ZnO is considered as a favorable photocatalyst due to its excellent photoelectrochemical properties. However, low response of visible light and the recombination of photoinduced carriers limits its application in photocatalysis. Herein, a novel, robust and recyclable heterogeneous photocatalyst based on flower-like Co doped ZnO microspheres was presented without changing the hierarchical morphology. The crystal structure, light absorption, and electrochemical performance were systematically investigated, and the response of Co doped ZnO to visible light significantly enhanced with the gap band reduced from 3.20 eV to 2.54 eV. Due to the transformation of Co2+ to Co3+, more oxygen vacancies were produced, with more photoinduced electrons transferring to Co3+ which would greatly inhibit the recombination of photoinduced electrons and holes and improve photocatalytic activity. 2-Mercaptobenzothiazole (MBT) which is considered as a long half-life intermediate of antibiotic medicine is chosen as a target. As a result, the 7% Co-ZnO photocatalyst exhibited excellent photocatalytic activity for the degradation of MBT with the rate constant of 0.1498 min−1 and removing ratio of 97.3% in 50 min. The formation of excess oxygen vacancies and the conversion between Co2+ to Co3+ were further identified by XPS analysis. This work provides new sights for doping transition metal with different chemical valence in semiconductors for producing oxygen vacancy and improving the photocatalytic efficiency. [Display omitted] • A novel and recyclable heterogeneous flower-like Co doped ZnO microspheres is prepared via simple procedure. • Doping of Co species effectively reduces the band gap energy of ZnO with the formation of abundant oxygen vacancies. • Electrons are trapped due to the transformation of Co2+ and Co3+ which hinders the recombination of photo-induced carriers. • The formation of oxygen vacancies and the conversion between Co2+ to Co3+ are further identified by XPS analysis. • The prepared photocatalyst exhibits excellent photocatalytic activity for degradation of 2-mercaptobenzothiazole. [ABSTRACT FROM AUTHOR]

Highlights: [•] The impact of market concern derived from the Web on oil volatility is analysed. [•] It has an equilibrium relationship between oil prices and long-run market concern. [•] The short-run market concerns have an asymmetric influence on oil price volatility. [•] The Internet can exaggerate the impact of information shocks on oil price. [ABSTRACT FROM AUTHOR]

The DFT-B3LYP/6-311++G(3df,2p) and MP2(full)/6-311++G(3df,2p) calculations were carried out on the binary complex formed by HM (M = Li, Na, K) and HF or the π-electron donor (CH, CH, CH), as well as the ternary system FH∙∙∙HM∙∙∙CH/CH/CH. The cooperativity effect between the dihydrogen-bonding and H-M∙∙∙π interactions was investigated. The result shows that the equilibrium distances R and R in the ternary complex decrease and both the H∙∙∙H and H-M∙∙∙π interactions are strengthened when compared to the corresponding binary complex. The cooperativity effect of the dihydrogen bond on the H-M∙∙∙π interaction is more pronounced than that of the M∙∙∙π bond on the H∙∙∙H interaction. Furthermore, the values of cooperativity effect follow the order of FH∙∙∙HNa∙∙∙π > FH∙∙∙HLi∙∙∙π > FH∙∙∙HK∙∙∙π and FH∙∙∙HM∙∙∙CH > FH∙∙∙HM∙∙∙CH > FH∙∙∙HM∙∙∙CH. The nature of the cooperativity effect was revealed by the analyses of the charge of the hydrogen atoms in H∙∙∙H moiety, atom in molecule (AIM) and electron density shifts methods. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: A new plasmonic photocatalyst of Ag–AgCl@TiO2 was prepared by deposition–precipitation and photoreduction. This photocatalyst exhibited efficient photocatalytic activity for the degradation of 4-chlorophenol and photoreduction of Cr(VI) ion under visible light irradiation. Its high photocatalytic activity can be attributed to the surface plasmon resonance effect of Ag nanoparticles, which were highly dispersed on the surface of Ag–AgCl@TiO2. N2 adsorption and desorption isotherm spectra, X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy were used to determine the correlation between the micro-structure and the catalytic properties of the as-prepared photocatalysts. [Copyright &y& Elsevier]

Abstract: A new plasmonic photocatalyst of Ag–AgI/Fe3O4@SiO2 was prepared by deposition–precipitation and photoreduction method. The catalyst exhibited efficient photocatalytic activity for the degradation of rhodamine B dye and 4-chlorophenol under visible light irradiation. The degradation rate of rhodamine B and 4-chlorophenol over Ag–AgI/Fe3O4@SiO2 was about 10 times and 4.1 times faster than that of N–TiO2, respectively. The catalyst could be easily recovered due to its paramagnetic property. X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscope were used to characterize the catalyst. The specified photocatalytic reaction and the study of electron paramagnetic resonance verified that both the O2 − glyph name="rad" />OH radicals were the main active species in this reaction. [ABSTRACT FROM AUTHOR]

As a well-known numerical approximation method, the least squares fitting method is widely applied in surveying engineering. The most important and difficult problem in this method is to determine the type of base function to be used, and polynomial is the most frequently used type. But if the degree of polynomial is too high (>=7), the normal equations are usually ill-conditioned. When we choose the uniform B-spline as the basis, there are two problems: (1) if we require the known data points to be an equidistant grid, it can only be applied in limited field; and (2) if the known data points are scattered, it is very difficult to obtain satisfactory results by using the uniform B-spline method. The purpose of this paper is to present the least squares fitting method based on a bivariate nonuniform B-spline. The principles and algorithms of this least squares fitting method are developed. Based on this method, two numerical simulations and one application in regional gravity field approximation are discussed. [ABSTRACT FROM AUTHOR]

In China, energy use from passenger vehicles is increasing rapidly due to urbanization and income growth, but the contributions of transport service structure shift and energy efficiency improvement, especially future energy-saving directions are controversial and unclear because of the differences in the choices of traffic modes, which may greatly affect the analysis results and their interpretations. This study investigates the growth sources of energy use in the passenger transport sector during 1979–2017 and future energy-saving potentials by 2030 by re-examining statistical data. Results show that the transport service increase and transport structure shift led to the increase in energy use by 665.25% and 337.22%, but approximately 14% of the increased energy use was offset by energy efficiency improvements, and its effect is limited in public transportation sector, compared with private passenger vehicle sector. In public passenger transport sector, adjusting the service or volume structure may be a desirable option while in private passenger vehicle sector the policy focus is more on improving fuel efficiency and reducing average annual kilometers traveled per capita. Overall, there is still at least 28.3% of energy reduction potential by energy efficiency improvement before 2030 compared to 2017 baseline level. Potential evaluation showed that the current potential of transport service structure adjustment based on industrial planning is limited, which highlights the necessity of reform, involving promoting the sharing transportation, railway, subway and buses. • Energy growth sources of passenger transport energy use are completely examined. • Transport structure shift caused energy consumption to increase by 337.22%. • Impact of energy efficiency improvement is limited in public transport sector. • There are distinct policy directions for public and private transport sectors. • There are huge energy-saving potentials in Chinese passenger transport sector. [ABSTRACT FROM AUTHOR]

While prior studies of consumer preferences on electric vehicles (EVs) utilized stated preference (SP) or revealed preference (RP) data, this study examined consumer preferences for EVs through their online behaviour. Using big data and text mining technologies to explore large quantities of Chinese consumers' online behaviour pertaining to EV selection, comparison, purchase inquiry, and comments, we found that EV prices, car classification and powertrain types were the most important factors influencing consumer response. In addition to general interests, we also noted application specific interests. For instance, we observed a preference for small battery electric vehicle (BEV) models with fast-charging batteries, which are well-suited to work commutes and daily life. By contrast, when examining plug-in hybrid electric vehicles (PHEVs), we noticed that consumers expressed a preference for sport utility vehicle (SUV) models. Finally, we found that in addition to price and technical specifications, EV aesthetics play a significant role in consumer choice. These conclusions are valuable for government agencies and EV manufacturers looking to promote EVs and address environmental pollution by appealing to consume interests. [ABSTRACT FROM AUTHOR]

Sodium praseodymium orthophosphate Na 3 Pr(PO 4 ) 2 was prepared using high temperature molten salt method and structurally characterized by single-crystal X-ray diffraction (SC-XRD) analysis. Its structure can be modeled as a four-dimensional (4D) commensurately modulated structure with orthorhombic superspace group Pca 2 1 (0 1/3 0)000 or as a conventional 3D superstructure description. The structure contains PrO 8 , NaO 6 , NaO 7 and PO 4 polyhedra, which are in six types of linear array along the a -axis. Furthermore, the excitation and emission spectra, decay time and Commission International de l’Éclairage (CIE) chromaticity index of Na 3 Pr(PO 4 ) 2 were studied. Under blue light excitation (468 nm), the powdered Na 3 Pr(PO 4 ) 2 calcined at 1200 °C shows the strongest red emission at around 610 nm, which originates from the 3 P 0 → 3 H 6 and 1 D 2 → 3 H 4 transformations of Pr 3+ ion. [ABSTRACT FROM AUTHOR]

Summary Objectives The aims of this study were to determine the mechanism of an outbreak of measles in adults and to provide scientific measures for putting forward a measles elimination program. Methods We performed a cross-sectional investigation during the measles outbreak to identify a possible communication link. Results From November 1, 2011 to January 26, 2012, the town reported 11 cases of measles in total. The case study identified an obvious propagation chain, which showed ordered and intimate exposure between cases. Conclusions Hospital exposure 1–2 weeks before infection with measles was the main cause of the measles outbreak. We must be fully aware of the possibility of nosocomial infection in an outbreak of measles; controlling nosocomial infections is a vital step in the prevention and control of the propagation of measles. [ABSTRACT FROM AUTHOR]

BACKGROUND: Accumulated studies have suggested that single nucleotide polymorphisms (SNPs) in microRNAs are associated with risk of colorectal cancer (CRC). OBJECTIVE: We tested our hypothesis that rs11014002 in hsa-miR-603 may be associated with CRC risk with a crosstalk of life-related factors. METHODS: We conducted a case-control study which included 102 CRC patients and 204 matched cancer-free controls in Xiaoshan County. RESULTS: We observed that subjects with rs11014002 CT/TT genotype had an increased susceptibility for CRC (CT vs. CC: odds ratio (OR)=2.352, 95% confidence interval (CI): 1.142-4.840, P=0.020; CT+TT vs. CC: OR=2.031, 95% CI: 1.063-3.883, P=0.032). After stratification by lifestyle-related factors, similar results were found among nonsmokers (CT vs. CC: OR=2.753, 95% CI: 1.085-6.983, P=0.033; CT+TT vs. CC: OR=2.971, 95% CI: 1.188-7.435, P=0.020) and non-alcohol drinkers (CT+TT vs. CC: OR=3.279, 95% CI: 1.071-10.033, P=0.037). CONCLUSIONS: Our data suggest that hsa-miR-603 may be involved in colorectal tumorigenesis, and the genetic polymorphism in hsa-miR-603 is associated with CRC susceptibility. [ABSTRACT FROM AUTHOR]

Abstract: By combing 4π liquid scintillation (LS) and γ spectrometry, we proposed a new approach, which is based on the linearity of the energy and the efficiency of coaxial HPGe detectors in logarithmic coordinates, to determine the radioactivities of nuclides with 200–2000 keV γ ray(s). In this approach, the multi-gamma-ray nuclide 152Eu has been applied to obtain the slope of energy-efficiency line. Meanwhile, the intercept of the energy-efficiency line is obtained by determining the 661.657 keV γ ray radiation of 137Cs whose radioactivity is determined by 4π LS. For the fixed source-detector geometry of this study, the energy-efficiency line is: lgɛγ  = −0.9503lgEγ  + 0.5224. This simple approach is promising to be used to determine the radioactivities of all the nuclides which emit γ ray(s) with the energy (energies) between 200 and 2000 keV in the absence of efficiency calibration standard. The relative standard deviation of the approach is about 5.7%. [Copyright &y& Elsevier]