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The optimal preventive maintenance timing of traditional asphalt pavement is based on the maximum benefit-cost ratio. For cost evaluation indicators, mainly agency cost and user cost, use life cycle cost analysis (LCCA) to determine. The environmental impact of pavement preventive maintenance activities is often overlooked. For the benefit evaluation index, only the new area under the performance curve is used to express the maintenance benefit, and the benefit evaluation index is single. This study proposes an integrated approach combining life cycle assessment (LCA) and LCCA to model preventive maintenance timing decisions considering economic, social, and environmental factors. In this paper, LCA is used to quantitatively analyze the energy consumption and emissions in the pavement operation and maintenance process, and the environmental costs are also included in the accounting scope of the costs. The costs that constitute pavement use are analyzed from three aspects: the agency cost, the user cost, and the environmental cost. At the same time, in the process of constructing the cost model, the costs caused by the maintenance construction process to users and the environment are also taken into consideration. Aiming at the benefit index and comprehensively considering the economic benefits, social benefits, and environmental benefits brought by maintenance, a comprehensive evaluation model of maintenance benefits was constructed based on the analytic hierarchy process (AHP). On the basis of accurately calculating the cost and benefit of maintenance in the life cycle, the model of the optimal preventive maintenance timing of asphalt pavement is constructed so as to calculate the optimal timing of preventive maintenance and provide certain information for the formulation of expressway pavement preventive maintenance programs. For reference. Taking a highway project in China as an example to verify the applicability of the model [ABSTRACT FROM AUTHOR]

The aim of this article was to analyze the monitoring status of nitrite in meat products consumed from 2000 to 2011 in 24 provinces, autonomous regions or direct-controlled municipalities in China. Statistical analyses were performed on the monitoring status including number, proportion, and distribution of 13,316 samples, of which 11,320 (85%) contained up to 2808.2 mg/kg nitrite and 1996 (15%) contained no nitrite. A total of 10,299 samples (77%) qualified for GB/T 5009.33-2003, 2003; however, 3017 samples (23%) contained nitrite at levels higher than the national standard. The districts with high percentage of samples with no nitrite were Shanghai (49%), Beijing (47%), and Liaoning (30%). While the districts with high percentage of meat products containing nitrite at levels exceeding the national standard were Jiangxi (49%), Jiangsu (33%), Shandong (29%) and Sichuan (29%). Therefore, the status of residue nitrite in meat products is of concern. [ABSTRACT FROM AUTHOR]

• Based on the 2017 I-O table, we developed an environmental CGE model. • The effects of changes in the policy for promoting EV were evaluated. • The subsidy brings positive impacts on the economy but increases the overall emissions. • The substitution ratio between EV and ICEV was evaluated. Environmental issues as pollutant emissions and resource depletion urge people to seek a replacement for the internal combustion engine vehicle (ICEV). Electric vehicles (EV) are considered as the preferred alternative to address these problems by means of reducing the use of fossil energy. After implementing many years of the incentive policy, the market share of electric vehicles has experienced great growth in China. Recently, the government considers the phase-out of the subsidy within 3 years. In this study, based on the 2017 social accounting matrix (SAM), we build a computable general equilibrium (CGE) model. And five scenarios are developed to evaluate the environmental and economic impacts of the policy changes, specifically, the decreasing subsidy and the sustained technological progress requirements. The results reveal that both the subsidy and technological progress can contribute to the economic growth, and a 30% cutback of subsidy does weaken the economic benefit by 23.5%-33.3%. And the subsidy increases the overall emissions greatly while technological progress contributes to emission reductions. Another finding is that the substitution ratio between ICEV and EV is roughly 1:3 under the effect of the subsidy. However, technological progress provides a ratio of 1:1.3, close to the perfect 1:1 substitution commonly assumed in life cycle assessment (LCA) studies. Our study suggests that compared with the subsidy, encouraging technological progress is a more sustainable option for policy-making. [ABSTRACT FROM AUTHOR]

A comprehensive assessment of the environmental performance of products in heavy industries is indispensable in unraveling the environmental pollution and resource shortage in the manufacturing industry of China. To quantify the environmental emissions and resource consumption in the holistic life cycle and identify the hotspots, this study applies the life cycle assessment to an 18.4 MW class domestic large-scale centrifugal compressor and compares the environmental impacts of the overall milled impeller and the welded impeller. Six environmental indicators—, namely, primary energy demand (PED), global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), ozone layer depletion potential (ODP), and photochemical ozone creation potential (POCP) are considered in this case study. Usage, raw material production, and manufacture are the top three contributors to the entire emissions and resource utilization. The environmental impacts comparison of impellers reveals that welded impeller is more environmentally favorable in terms of PED, GWP, AP, EP and ODP. Results of this study can provide a scientific basis for compressor manufacturers to minimize the environmental burdens from the life cycle perspective. [ABSTRACT FROM AUTHOR]

Seroprevalence of Toxoplasma gondii infection was determined in sera of 632 dogs (551 pets, 81 strays) from Shandong, Henan, and Heilongjiang Provinces, and in the Xinjiang Uygur Autonomous Region, People's Republic of China (PRC), using the indirect hemagglutination assay (cutoff titer 1:64 or higher); 11.1% were seropositive. The seroprevalence in stray dogs and in ≥3-yr-old dogs was significantly higher (P < 0.05) than that in household dogs and in <3-yr-old dogs. There were no significant differences in terms of gender, breed, or locality (P ≥ 0.05). The results indicate that T. gondii infections are common in dogs in PRC.