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BixOyBrz photocatalysts exhibit great potential in the application of organic pharmaceutical wastewater treatment and air purification. However, the catalysis activity and application of photocatalyst is greatly limited by its intrinsic high recombination rate of photo-generated charge carriers. In this work, a novel Bi3O4 Br / Bi12O17 Br2 composite photocatalyst was prepared via a facile in-situ hydrolysis-calcination route and its photocatalytic performance was evaluated by the sulfamethoxazole (SMX) degradation efficiency via simulated solar light irradiation. The structure and property were analyzed by X-ray diffraction ( XRD), X-ray photoelectron spectroscopy ( XPS), scanning electron microscopy ( SEM), nitrogen adsorption and desorption, UV-Vis diffuse reflectance spectra ( UV-Vis DRS), electrochemical impedance spectroscopy (EIS), Steady photoluminescence and Mott-Schottky curves. Results reveal that Bi3O4Br/Bi12O17 Br2 composite photocatalyst display the optimum photocatalytic performance, and its removal efficiency of SMX reaches 87% under 30 min simulated solar light irradiation, which is improved approximately 30% and 24% than that of pure Bi3O4Br and pure Bi12O17Br2, respectively. Based on characterization analysis, the superior performance is attributed to higher electron-hole separation rate and lower charge transfer resistance. Finally, the underlying photocatalytic mechanism was elucidated based on the band structure and radical scavenging experiments. This findings provide novel ideas and methods of the construction of the composite photocatalysts system for strong organics pharmaceutical wastewater treatment. [ABSTRACT FROM AUTHOR]

Shanghan Lun is based on "exogenous cold disease," the change rules of a series of diseases such as superficies tightened by wind-cold and yang deficiency and internal cold, and the rules of treatment based on syndrome differentiation have had a profound impact on traditional Chinese medicine in later generations. Formulae with the name of "Sini" and its variations have the effect of treating deadly cold limbs in Shanghan Lun, for example, Sini Decoction, Tongmai Sini Decoction, Baitong Decoction, Fuling Sini Decoction, Sini Renshen Decoction, Danggui Sini Decoction, and Sini Powder, etc. Their corresponding constitution characteristics, etiology and pathogenesis, changes in disease status, and clinical manifestations have certain commonalities. This paper discusses and analyzes the modifications of the "Sini" formulae, the rules of the formulae, and the principles of application based on the characteristics of yang deficiency constitution, their susceptibility to disease, and the evolutionary pattern of yin excessiveness due to yang deficiency pathogenesis. Our aim is to deepen the knowledge and understanding of the application of the "Sini" formulae from the perspective of yang deficiency constitution and to provide research ideas for the comprehensive study of "constitution-disease-syndrome differentiation". [ABSTRACT FROM AUTHOR]

Urban sprawl has become a widespread trend for developing countries. Road networks are an extremely important factor driving the expansion of urban land and are thus subject to special attention from academia. For the purpose of studying the relationship between road networks and urban sprawl based on multi-period remote sensing images and vector data of urban road networks, we took Beijing, New York, London and Chicago as the study areas, and firstly attained urban land use vector data through image interpretation with the aid of a remote sensing and GIS platform; and then utilized overlay analysis to extract the information on urban sprawl. A map of road network density was further generated and manufactured using the density analysis tool of ArcGIS. Finally, we conducted a spatial statistical analysis between road networks and urban sprawl and then systematically analyzed their distribution features. In addition, the Urban sprawl-road network density model was established by regression analysis used for fitting the relationship. The results proved that 1) in the last 3 decades, there had been a consistency in terms of urban land expansion features of the 4 cities. The area of urban land expansion was gradually reducing from the center outward, while the distribution of road network density overall was gradually thinner from the city center outward. There was a close association between urban land expansion and spatial density of road network. Due to different locations, there were some differences in spatial distribution for urban expansion. 2) The urban sprawl thresholds of Beijing, New York, London and Chicago were 1.89×104, 3.78×104, 5.70×104 and 6.47×104 km/km2, respectively, and urban expansion had an inverted U-shaped curve relationship with road networks when the road network density did not exceed the threshold. 3) The turning points for urban sprawl for Beijing, New York, London and Chicago were 3.3×103, 11.84×103, 16.86×103 and 21.40×103 km/km2, respectively, which indicated that urban expansion initially accelerated with the increasing of the density of road networks; however, after the turning point was reached, the expansion rate of urban decreased; and when the road density exceeded the threshold, urban areas would no longer expand. 4) The road network played a driving role for urban expansion, inducing urban land expansion. Thus, the construction process of urban transport systems required strict proof, and we should give a scientific definition to the capacity of transportation, the amount of road networks and the road network layout. The correlation between urban sprawl and road network features had an important reference for the future development of global developing cities. Understanding road network density offered some predictive effects for urban land expansion, allowed the avoidance of irregular expansion, and provided new ideas for addressing the inefficient utilization of land and other issues. The tendency for urban expansion varied with the degree of road network development in different locations, and exerting the law was conducive to scientific planning and rational use of the land in city and to the improvemente of land use efficiency. In short, the quantitative relationship between road networks and urban sprawl presented an inverted U-shaped pattern. A reasonable grasp of the turning point for urban expansion was worth pondering for other cities in the stage of rapid development in order to promote sustainable development and achieve smart growth in the future. Therefore, we should pay attention to the role of urban road network planning and promote urban's "smart growth" in order to achieve mutual promotion and coordinated development of urban land use and road network construction. [ABSTRACT FROM AUTHOR]