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Chlorinated paraffins (CPs) are hazardous to humans, and dietary intake acts as the primary pathway for human exposure to CPs. Takeout food is popular worldwide, but the presence of CPs in takeout food and its packaging is unclear. In this study, the concentrations and distributions of short- and median-chain CPs (SCCPs and MCCPs, respectively) were measured in 97 samples of four categories of takeout food and 33 samples of three types of takeout packaging. The SCCP and MCCP median concentrations for the takeout food samples were 248 and 339, 77.2 and 98.2, 118 and 258, 42.9 and 64.4 ng/g wet weight in meat, starch, half meat/half starch, and vegetables, respectively. Takeout food contained higher concentrations of SCCPs than MCCPs. The dominant SCCP and MCCP congener groups in takeout food were C 10 Cl 6–7 and C 14 Cl 7–8 , respectively. The CP concentrations in takeout food were lower than those in packaging. The SCCP and MCCP median concentrations, respectively, in packaging were 9750 and 245 ng/g in polypropylene, 2830 and 135 ng/g in paper, and 2060 and 119 ng/g in aluminum foil. The concentrations of SCCPs and MCCPs were comparable in aluminum foil, whereas the concentrations of SCCPs were higher than those of MCCPs in polypropylene and paper. Correlations between CP concentrations in the takeout food and packaging indicated that CPs in packaging were potentially an important source of CPs in the takeout food. A dietary exposure risk assessment showed the takeout food posed a low risk for human exposure to CPs; however, high-frequency consumption may pose a health risk. This study clarified the current contamination situation in takeout food in Beijing, China. The resulting data could be used to prevent human exposure to CPs through dietary intake and to facilitate the market's control over the quality of takeout food. • Chlorinated paraffin (CP) concentrations are highest in animal-origin takeout food. • CP concentrations are highest in polypropylene and lowest in aluminum foil. • Shorter carbon chain and lower chlorination CPs are dominant in food and packaging. • CPs in packaging are a potential source for CPs in takeout food. • The human exposure risk to CPs through takeout food intake is low. [ABSTRACT FROM AUTHOR]

Abstract With the wide application of big data technology and the continuous innovation of the financial industry, the development of Internet finance has become irreversible. The new financial model has improved the efficiency of financial services and formed new ways of payment and transaction. The traditional credit information system has been unable to meet the needs of the development of the financial industry. The research methods adopted in this paper mainly include literature research, case analysis and comparative analysis. The development process, current situation and characteristics of China's personal credit system, as well as the development process and current situation of China's personal credit system under Internet finance are analyzed. It also points out the main problems faced by China's personal credit reporting system under the Internet finance. Then, aiming at the specific problems faced by China's personal credit reporting system under Internet finance, this paper makes case studies of representative market-oriented credit reporting institutions such as Beijing, Tianjin and Hebei, and uses convolutional neural network to analyze the specific practices of these individual credit reporting institutions and achieves results. At the same time, it compares how different credit agencies make up for the shortcomings of personal credit reporting system. Finally, it draws the conclusion of perfecting the personal credit system of our country under the Internet finance, points out the new problems that may be brought by the superposition of various solutions, and puts forward the countermeasures and suggestions of perfecting the personal credit system of our country under the Internet finance. [ABSTRACT FROM AUTHOR]

Unit pricing for domestic waste, or pay-as-you-throw (PAYT), affords a promising policy option for waste classification and reduction at source. As an emerging economy, China intends to adopt the sophisticated instrument of unit pricing. The public attitude to this policy is of high relevance for its actual implementation. For the first time in China, this paper quantitatively examined the acceptability of the policy among urban residents by randomly delivering 632 questionnaires by taking Beijing, a megacity expected to introduce the practice, as an example. Based on the ordered logit model, determinants of acceptability were empirically tested including intrinsic, external and demographic factors. The results show that the acceptability rate of PAYT in Beijing is less than half, with the proportion of firm support reaching only 42.6%. The respectively low acceptability rate indicates substantial compliance costs, due to intensive resistance to policy implementation and more resources to be invested to promote acceptability. Empirical analysis further indicates that (1) regarding demographic features, aged or less educated residents tend to accept unit pricing, (2) as for intrinsic factors, a friendly environmental attitude, deeper understanding of charging policy and better social perception can significantly improve the public acceptability of the policy, and (3) in terms of external factors, better property services and transparent funding mechanisms play significant roles in enhancing public acceptability. These findings are further confirmed by replacing the dependent variable with either the willingness to pay for household waste disposal or the acceptability of the operated sewage treatment fee. The status of residents' preference for specific pricing methods is further investigated with underlying reasons being revealed. For developing regions with an urgent demand for waste reduction, it is proposed to install unit pricing in time to avoid possible growing social acceptability costs. Specific measures are proposed including changes in intrinsic factors, paying attention to focus groups, and building social consensus for unit pricing. [Display omitted] • Public acceptability of unit pricing policy is quantitatively examined in Beijing. • A random face-to-face survey is designed and conducted by covering 632 households. • The acceptability rate is only 42.6%, indicating high policy compliance costs. • Demographic, intrinsic and external factors play roles in improving acceptability. • Specific suggestions are proposed for regions like Beijing to introduce the policy. [ABSTRACT FROM AUTHOR]

China has begun a rapid move towards Sponge City implementation, which will include widespread installation of various Low Impact Development (LID) stormwater infrastructure. Ambitious goals have been set for all Sponge Cities, including a target capture rate of 80–85% of annual precipitation in Beijing. However, there has so far been limited investigation into whether these goals are obtainable at the catchment scale given the physical restrictions of the existing urban landscape. This paper demonstrates the use of long-term continuous hydrologic modelling to evaluate the potential of meeting rainfall capture goals over a long time period for a case study area in Beijing. Detailed land cover classification derived from satellite imagery aided in the parameterization of a SWMM (Stormwater Management Model) model representing a 133 km2 urban study area. The calibrated and validated model demonstrated satisfactory agreement between computed and observed runoff for a variety of precipitation events ranging from 10 to 207 mm. A synthetic high resolution rainfall time series was generated from historic daily observations then used as input to run the model continuously for a 35 year period. Feasible LID model scenarios based on varying degrees of implementation of rain gardens, permeable pavements and green roofs were compared in terms of their potential volume capture of annual rainfall. Modelling results demonstrated that the conversion of 30% of roof area to green roof, 10% of green areas to rain gardens and 35% of paved areas to permeable pavement could increase the baseline volume capture ratio from 59.9% to 82.2%, indicating that Sponge City goals can be met within the case study area with realistic levels of LID implementation. This study provides a decision-making basis for future planning in the study area. • Satellite imagery based hydrologic model shows good agreement with observed flows. • Continuous modelling approach suggested for evaluation of Volume Capture Ratio. • >80% of annual rainfall captured with moderate catchment wide implementation of LID. [ABSTRACT FROM AUTHOR]

Abstract The residential building sector consumes a large amount of energy and is recognized as a high potential area where urban energy consumption and carbon emission can be reduced. To reduce the residential energy consumption, relevant policies and measures have been formulated in different places. However, due to the lack of adequate information in the process of policy formulation, the effectiveness of most energy-saving policies for residential buildings seems to be unsatisfactory. Although previous studies have analyzed the energy consumption for a single building or for the whole construction industry at the national level, few of them investigated the life-cycle energy consumption of residential buildings at the city level. Since municipal governments are the key implementers for the reduction of urban energy consumption, a city-level analysis on the energy consumption of residential buildings is highly needed for the policy making. To fill the research gap, this paper develops a life-cycle dynamic simulation model to fully reveal the characteristics of energy consumption of residential buildings at the city level. This easy-to-use model is validated by a case study of Beijing, which demonstrates its applicability and capability to help analyze multiple indicators of residential energy consumption and the dynamic trends of these indicators for municipal governments. Furthermore, the model can be used under the condition of limited input data, and can provide the situation analysis and simulation results of energy consumption of urban residential buildings for facilitating the policy making by municipal governments. Graphical abstract Image 1 Highlights • The proposed model can analyze city-level energy consumption of residential buildings. • The model can be used with relatively limited amounts of input data. • Operation stage accounts for 67% of total residential energy consumption in Beijing. • Heating is the most energy-intensive activity of operation stage in Beijing. • Policy implications for residential energy saving are provided based on the model. [ABSTRACT FROM AUTHOR]

Currently, air pollution is primarily characterized by PM 2.5 and O 3. Therefore, the co-control of PM 2.5 and O 3 has become an important task of atmosphere pollution prevention and control in China. However, few studies have been conducted on the emissions from vapor recovery and processes, which is an important source of VOCs. This paper analyzed the VOC emissions of three vapor process technologies in service stations and first proposed key pollutants for priority control based on the coordinated reactivity of O 3 and SOA. The concentration of VOCs emitted from the vapor processor was 3.14–9.95 g m−3, compared to 631.2–717.8 g m−3 for uncontrolled vapor. Alkanes, alkenes, and halocarbons accounted for a high proportion of the vapor both before and after control. Among the emissions, i -pentane, n -butane, and i -butane were the most abundant species. Then, the species of OFP and SOAP were calculated through the maximum incremental reactivity (MIR) and fractional aerosol coefficient (FAC). The average source reactivity (SR) value of the VOC emissions from three service stations was 1.9 g g−1, while the OFP ranged from 8.2 to 13.9 g m−3 and SOAP ranged from 0.18 to 0.36 g m−3. By considering the coordinated chemical reactivity of O 3 and SOA, a comprehensive control index (CCI) was proposed for the control of key pollutant species that have multiplier effects on environment. For adsorption, trans -2-butene and p -xylene were the key co-control pollutants, while toluene and trans -2-butene were the most important for membrane and condensation + membrane control. A 50% emission reduction of the top two key species that emission account for 4.3% averagely will reduce O 3 by 18.4% and SOA by 17.9%. [Display omitted] • The organized emissions of VOCs from three vapor processors were studied in service stations. • The species composition of VOCs before and after control were analyzed. • The OFP and SOAP were calculated to evaluate the secondary pollution. • The co-control of key pollutants based on SOA and O 3 has great environmental benefits. [ABSTRACT FROM AUTHOR]

Economic development, accompanying with environmental damage and energy depletion, becomes essential nowadays. There is a complicated and comprehensive interaction between economics, environment and energy. Understanding the operating mechanism of Energy-Environment-Economy model (3E) and its key factors is the inherent part in dealing with the issue. In this paper, we combine System Dynamics model and Geographic Information System to analyze the energy-environment-economy (3E) system both temporally and spatially, which explicitly explore the interaction of economics, energy, and environment and effects of the key influencing factors. Beijing is selected as a case study to verify our SD-GIS model. Alternative scenarios, e.g., current, technology, energy and environment scenarios are explored and compared. Simulation results shows that, current scenario is not sustainable; technology scenario is applicable to economic growth; environment scenario maintains a balanced path of development for long term stability. Policy-making insights are given based on our results and analysis. [ABSTRACT FROM AUTHOR]

This paper developed internationally compatible methods for delineating boundaries of urban areas in China. By integrating emission source data with existing official statistics as well as using rescaling methodology of data mapping for 1 km grid, the authors constructed high resolution emission gridded data in Beijing-Tianjin-Hebei (Jing-Jin-Ji) region in China for 2012. Comparisons between urban and non-urban areas of carbon emissions from industry, agriculture, household and transport exhibited regional disparities as well as sectoral differences. Except for the Hebei province, per capita total direct carbon emissions from urban extents in Beijing and Tianjin were both lower than provincial averages, indicating the climate benefit of urbanization, comparable to results from developed countries. Urban extents in the Hebei province were mainly industrial centers while those in Beijing and Tianjin were more service oriented. Further decomposition analysis revealed population to be a common major driver for increased carbon emissions but climate implications of urban design, economic productivity of land use, and carbon intensity of GDP were both cluster- and sector-specific. This study disapproves the one-size-fits-all solution for carbon mitigation but calls for down-scaled analysis of carbon emissions and formulation of localized carbon reduction strategies in the Jing-Jin-Ji as well as other regions in China. [ABSTRACT FROM AUTHOR]

The green growth of Beijing-Tianjin-Hebei (BTH) urban agglomeration plays a leading and exemplary role in overcoming internal resource restrictions, addressing climate change, and supporting China's high-quality growth. From the standpoint of pollution reduction and carbon reduction, this paper first conducts a comprehensive evaluation of the environmental impact based on combined weighting technique. The Logarithmic Mean Divisia Index (LMDI) model is used to decompose the environmental impact drivers in distinct areas. A decoupling effort index is further constructed to measure the effect of various efforts on the decoupling of economic growth and environmental impact, the improved grey Markov model is applied to predict the future trend of regional decoupling efforts. The results of empirical analysis based on data of the BTH region during 2011–2018 show that: 1) the environmental impact index of Beijing is the lowest followed by Tianjin and Hebei; 2) environmental regulation exerts the most significant impact on reducing environmental pressure in Beijing while technology progress and energy intensity have the most significant effect on easing environmental pressure in Tianjin; 3) strong decoupling efforts have been found in Beijing, Tianjin and Hebei, however, such effect is more significant in Beijing; 4) Beijing's decoupling state is mostly driven by regulatory effect, intensity effect, and scale effect, while Tianjin and Hebei's decoupling states are primarily driven by improvements in environmental regulation and energy intensity; 5) according to the forecast outcome of the improved grey Markov technique, a state of strong decoupling effort will be maintained in the BTH area by 2025, and the decoupling effort index in Beijing will remain the highest while the index in Hebei will remain the lowest. • A comprehensive evaluation of the environmental impact of BTH based on combined weighting method is estimated. • Determinants of environmental impact is decomposed as regulatory, technological, intensity, growth and scale effects. • LMDI model is constructed to estimate the five determinants of regional environmental impact. • Decoupling effort approach and improved grey Markov model are used to analyze and predict the status of various decoupling efforts. • Various suggestions are proposed from the perspective of regional heterogeneity. [ABSTRACT FROM AUTHOR]

One year-long criteria air pollutants data collected in Beijing were analyzed in this paper, which can support the research on formation, transport and human health effects of air pollutants. This is the first time to study the spatial and temporal variations of criteria pollutants in Beijing using hourly observational data from 12 sites between June 2014 and May 2015 released by the Ministry of Environmental Protection (MEP) of China. Beijing is facing tremendous air pollution as the daily averaged PM 2.5 (particulate matter with aerodynamic diameter less than 2.5 µm) concentrations in all sites exceeding the Chinese Ambient Air Quality Standards (CAAQS) Grade I & II standards (15 and 35 µg/m 3 ). Slightly differences in PM 2.5 and ozone (O 3 ) were observed between sites at the urban and rural areas. Pearson correlation coefficients show that most pollutants are temporally correlated in Beijing except for O 3 . The coefficients of divergence (COD) indicate that PM 2.5 is associated at most sites with only one rural site (Dingling) having observable difference and one site may be insufficient for monitoring surrounding area. The 8 h peak O 3 (O 3 -8 h) also correlates at different sites but with one urban site (Haidianquwanliu) different from others. In addition, an extreme PM 2.5 event (hourly average concentration exceeding 300 μg/m 3 for ~40 h) was examined with the consideration of meteorological conditions. Southerly wind with low speed and high relative humidity allow the accumulation of pollutants while northerly wind with high speed and low relative humidity result in good air quality. [ABSTRACT FROM AUTHOR]

While numerous studies have shown that rail transit investment increases property value close to stations, not much has been said on the transit-induced indirect changes in neighborhood amenities and their role in property market's response to transit investment. The rapid expansion of Beijing's subway system over the last decade provides a precious opportunity to research the transit—retail amenities—property value connection. This paper enhances our knowledge by studying how local consumer amenities react to urban rail transit development and subsequently reflect in consumers’ willingness to pay. Using multiyear subway construction history, station neighborhoods’ restaurant activities and rental housing transactions in Beijing, we find a new subway station positively contributes to the number of new openings and the diversity of nearby restaurants. The changes in neighborhood restaurant activities capture 20–40% of the home value appreciation following the construction of a subway station. Our findings support the “multiplier effect” of neighborhood retail amenities in rail transit's impact on local home value. The public investment in transit and the private market responses complement each other and together contribute toward urban quality of life, as revealed by the appreciation in local property values. [ABSTRACT FROM AUTHOR]

Traffic phenomena are associated with a complex dynamic behavior of spatiotemporal traffic patterns. It is possible to understand the features of real traffic by a spatiotemporal analysis approach for real measured traffic data. In this paper, a space-time visualization analysis method is designed and carried out for taxi spatiotemporal dataset from Beijing floating car data acquisition system and Beijing GIS data. Through this method, large-amount taxi GPS data is processed and the spatial–temporal trajectory is analyzed. And then taxi daily operation time, operating range and residence location of individual driver, vehicle operation and rest periods and other indicators are calculated, which are important characteristic parameters of Beijing Taxi Operations. In sum, continuous, comprehensive, and dynamic analysis information for monitoring taxi operation status can be acquired through the method. These information can provide the decision basis for city taxi operation management, and help to improve the city taxi operation management level. [ABSTRACT FROM AUTHOR]

In 2010, the WHO guidance document for the evaluation of cell substrates for producing biologicals was replaced with updated recommendations and in May 2013 an implementation workshop on the new recommendations was held in Beijing, China. As part of this workshop, a survey of the use and evaluation of cell substrates for producing biologicals was undertaken and the information obtained was updated in June 2014. The purpose of survey was to capture the status of national requirements related to cell substrates in various countries with particular emphasis on whether or not the updated WHO recommendations had been, or were to be, incorporated into national requirements. This paper reports the outcome of the survey and is based on information provided by regulators in eleven countries. Since the publication of the updated WHO recommendations, several activities such as the implementation workshop and publications have been undertaken by the WHO. The aim of these activities, including the publication of this article, is to contribute to the implementation of WHO recommendations so as to reduce regulatory gaps between national requirements and globally agreed expectations. [ABSTRACT FROM AUTHOR]

Land-use suitability analyses are of considerable use in the planning of mega-cities. An Urban Development Land-use Suitability Mapping (UDLSM) approach has been constructed, based on opportunity and constraint criteria. Two Multi-criteria Evaluation (MCE) methods, the Ideal Point Method (IPM) and Ordered Weighted Averaging (OWA), were used to generate the opportunity map. The protection map was obtained by means of constraint criteria, utilizing the Boolean union operator. A suitability map was then generated by overlaying the opportunity and protection maps. By applying the UDLSM approach to Beijing, its urban development land-use suitability was mapped, and a sensitivity analysis undertaken to examine the robustness of the proposed approach. Indirect validation was achieved by mutual comparisons of suitability maps resulting from the two MCE methods, where the overall agreement of 91% and kappa coefficient of 0.78 indicated that both methods provide very similar spatial land-use suitability distributions. The suitability level decreases from central Beijing to its periphery, and the area classed as suitable amounts to 28% of the total area. Leading attributes of each opportunity factor for suitability were revealed, with 2256 km 2 , i.e. 70%, of existing development land being overlaid by suitable areas in Beijing. Conflicting parcels of land were identified by overlaying the resultant map with two previous development blueprints for Beijing. The paper includes several recommendations aimed at improving the long-term urban development plans for Beijing. [ABSTRACT FROM AUTHOR]

• A hybrid technique is presented to predict underground train induced vibration. • This prediction is based on transfer function experiments in a borehole or tunnel. • A vehicle-track model is used to obtain excitation forces acting on tunnel invert. • More accurate prediction can be expected compared to other approaches. The accurate prediction of ground-borne vibration induced by underground trains is needed to assess the effects of vibration. However, there are inaccuracy and uncertainty for current empirical and numerical approaches due to theoretical assumptions, simplifying modeling and uncertainty of parameters. To reduce the inaccuracy and uncertainty, this paper presents a prediction strategy based on the transfer function experiment in a borehole or tunnel. The frequency-domain dynamic response in the ground can be determined from the excitation forces applied on the tunnel invert and the transfer functions in the experiment. A vehicle-track model is established to obtain the excitation forces, and the transfer functions are measured in the hammer impact experiments in a borehole or tunnel. Validation of this approach is provided by comparison to the measured response on a metro line in Beijing. It is shown that more accurate prediction can be expected by this approach as the actual transfer characteristics of vibration in the ground are measured. [ABSTRACT FROM AUTHOR]

This paper explores the differences between public perceptions and existing monitoring indicators in environmental quality in Beijing. The results reveal, existing indicators do not accurately reflect public perceptions of the environment. Some environmental problems, such as fluffy catkins, are not reflected in the existing indicators, yet have a relatively large influence on public perception. The policymakers and public's variegated understanding of the environment, the lag period of public perceptions of environmental quality change, and lack of standards and monitoring for emerging problems are the three main reasons that resulted in a deviation of monitoring indicators from the public perceptions. Resultantly, to improve the level of environmental governance, it is necessary to take relevant measures that reduce the difference between public perceptions and monitoring indicators. Residents should be surveyed regularly to obtain their public perceptions, and the selection of indicators should not be limited to environmental pollution. In particular, some indicators based on public perception should be developed to complement the existing environmental monitoring protocol. In addition, due to the emerging environmental problems, quality standards and monitoring systems should be updated regularly. • Existing environmental monitoring indicators do not reflect public perceptions. • The selection of indicators should not be limited to environmental pollution. • Some indicators should be developed based on subjective perceptions. [ABSTRACT FROM AUTHOR]

The extreme high temperature weather event caused by global warming has increased the risk of urban electric power supply. Critical risk determination method is useful to the system risk prevention and adaptive strategy formulation. Based on analyzing the failure mechanism of power supply under heat wave impact, the paper put forward the method framework of energy-flow network on electric power system risk evaluation. There are three parts in the framework including energy-flow chart analysis of power supply and consumption, establishment and network analysis of Gephi visualization network, and matrix diagram evaluation of node importance. The visualized network of power system with different years and electricity input from external area were established and compared in the case study of Beijing in China. The analysis results showed that the network structure stability of the power system decreased slightly, which was due to the node energy flow becoming high imbalance such as power input from external area, local power generation and energy consumption. For risk prevention, power infrastructures should focus on the high-voltage transmission and distribution facilities and 500 kV hub substations. Meanwhile, to electric power generation and supply, natural gas supply and power supply from Inner Mongolia Autonomous Region played the key roles. And power consumption should focus on the tertiary industry and living consumption. • Energy-flow chart of power system was transformed into network by Gephi. • Node importance was evaluate by matrix diagram with node degree and edge weight. • Electric power system of Beijing was analyzed and discussed. • Energy-flow imbalance of system components reduced network system stability. [ABSTRACT FROM AUTHOR]

The housing affordability issue in mega-cities creates a significant job-housing mismatch and undermines productive new business creation. This paper focuses on Beijing and investigates whether improved accessibility via the subway network helps new firms benefit from agglomeration economies and, at the same time, provides workers with easy access the low-cost rental housing. Using commercial rental housing transaction records and dynamic bilateral subway travel time from 2010-2015, we build the measure of the accessibility to business clusters and low-cost rental housing through the subway network at a high spatial resolution. Taking advantage of exogenous shocks from the network reconfiguration due to the rapid subway expansion in Beijing, we employ a matched difference-in-differences estimation in multiple periods to identify the causal elasticity estimate of the new firm formation with respect to the accessibility to business clusters and low-cost rental housing. We demonstrate that the subway network is more conducive to firm establishments. The effects are more salient for firms in skill-intensive sectors. New skill-intensive firms increase by 0.44% given a 1% increase in the accessibility to business clusters. The elasticity of new skill-intensive firms with respect to the accessibility to low-cost rental housing is about 0.74. Our findings that transit-oriented development leads to a higher concentration of new skill-intensive businesses, pointing to the importance of an efficient public transit system capable of serving the dispersed workforce and improving the efficiency of firm location choice. [ABSTRACT FROM AUTHOR]