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Thermal insulation coating (TIC) is beneficial for reducing building energy consumption. In this work, a joint optimization and analysis approach for multi-parameters of TIC was proposed to determine its optimization trend, importance order of parameter and available parameter combinations. Its radiation characteristics and thermal resistance were comprehensively considered. Based on the approach, TIC was evaluated from energy saving rate of cooling (ESR cool), heating (ESR heat), and total energy consumption (ESR total) in two climates: hot summer cold winter (Shanghai), and hot summer warm winter (Guangzhou). Results indicated that constantly positive ESR cool was only achieved by optimizing solar absorptivity, while constantly positive ESR heat can be obtained by optimizing different parameters. To guarantee positive ESR total , thermal resistance should exceed 0.11 m2·K·W−1 or solar absorptivity should be between 0.2 and 0.6 in Shanghai, while solar absorptivity should be between 0.1 and 0.3 in Guangzhou. For these two cities, the most important parameter was thermal resistance or solar absorptivity. The optimal TIC for Shanghai was "high thermal resistance + low solar absorptivity + low emissivity", while high emissivity was suitable for Guangzhou. By utilizing the approach and results, energy-saving effect of TIC can be optimized during material design, and influence of material aging can be predicted. • A joint optimization and analysis approach for multi-parameters of TIC is proposed. • Optimization and deterioration impact of TIC multiple parameters is evaluated. • Parameter combination law for positive or negative energy saving rate is obtained. • Importance order of parameter is used for optimization design and material aging. • Effect of energy consumption caused by material aging consequences is predicted. [ABSTRACT FROM AUTHOR]

Nowadays, thermal conductivity as a key parameter affecting the thermal performance of PCM has attracted much attention. However, the thermal performance evaluation of ultra-high thermal conductivity PCM is scarce, especially in field of building energy conservation. Therefore, we traversed the range of thermal conductivity that can be prepared at present and within the expected time frame, which is 0.08–49.28 W ⋅ m − 1 K − 1 . In addition, a novel index, Utilization Rate of Latent Heat (URLH), was proposed to evaluate matching degree between PCM and a certain application background in buildings, so as to explore the reason of poor energy-saving effect of PCM under some application backgrounds. We found that the thermal conductivity of PCM is not the higher the better in buildings, in other words, a turning point appears. The optimal thermal conductivity is about 0.6 W ⋅ m − 1 K − 1 and when the value is lower than 0.3 W ⋅ m − 1 K − 1 , URLH is equal to 0 in the cases of Shanghai. Therefore, we recommend PCM researchers to evaluate the URLH before using PCM to avoid the ineffective use of materials. Through the analysis of URLH, researchers can know the specific parameters that affect the thermal performance of PCM and obtain the way to optimize them. [ABSTRACT FROM AUTHOR]

Air quality inside transportation carriages has become a public concern. A comprehensive measurement campaign was conducted to examine the commuters’ exposure to PM 2.5 (d p ⩽ 2.5 μm) and CO 2 in Shanghai metro system under different conditions. The PM 2.5 and CO 2 concentrations inside all the measured metro lines were observed at 84 ± 42 μg/m 3 and 1253.1 ± 449.1 ppm, respectively. The factors that determine the in-carriage PM 2.5 and CO 2 concentrations were quantitatively investigated. The metro in-carriage PM 2.5 concentrations were significantly affected by the ventilation systems, out-carriage PM 2.5 concentrations and the passenger numbers. The largest in-carriage PM 2.5 and CO 2 concentrations were observed at 132 μg/m 3 and 1855.0 ppm inside the carriages equipped with the oldest ventilation systems. The average PM 2.5 and CO 2 concentrations increased by 24.14% and 9.93% as the metro was driven from underground to overground. The average in-carriage PM 2.5 concentrations increased by 17.19% and CO 2 concentration decreased by 16.97% as the metro was driven from urban to the suburban area. It was found that PM 2.5 concentration is proportional to the on-board passenger number at a ratio of 0.4 μg/m 3 ·passenger. A mass-balance model was developed to estimate the in-carriage PM 2.5 concentration under different driving conditions. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the characteristics of dissolved organic nitrogen (DON) in raw water from the Huangpu River and also in water undergoing treatment in the full-scale Yangshupu drinking water treatment plant (YDWTP) in Shanghai, China. The average DON concentration of the raw water was 0.34mg/L, which comprised a relatively small portion (~5%) of the mass of total dissolved nitrogen (TDN). The molecular weight (MW) distribution of dissolved organic matter (DOM) was divided into five groups: >30, 10–30, 3–10, 1–3 and <1kDa using a series of ultrafiltration membranes. Dissolved organic carbon (DOC), UV absorbance at wavelength of 254nm (UV254) and DON of each MW fraction were analyzed. DON showed a similar fraction distribution as DOC and UV254. The <1kDa fraction dominated the composition of DON, DOC and UV254 as well as the major N-nitrosodimethylamine formation potential (NDMAFP) in the raw water. However, this DON fraction cannot be effectively removed in the treatment line at the YDWTP including pre-ozonation, clarification and sand filtration processes. The results from linear regression analysis showed that DON is moderately correlated to DOC, UV254 and trihalomethane formation potential (FP), and strongly correlated to haloacetic acids FP and NDMAFP. Therefore, DON could serve as a surrogate parameter to evaluate the reactivity of DOM and disinfection by-products FP. [ABSTRACT FROM AUTHOR]

• Public health professionals in China evaluated the roll-out of the hepatitis E vaccine. • Participants provided feedback on different institutions and feasible goals. • Medical doctors and the government had limited knowledge of hepatitis E. • The public sector was a trusted source of information. • Recommendations for promotion of the vaccine in the future are provided. A hepatitis E (HepE) vaccine was developed and released in China in 2011. Uptake is currently very limited. The aims of this study were to characterize what public health professionals thought about promoting the HepE vaccine in Shanghai, China, and to develop realistic goals for the HepE vaccine based on this information. Public health professionals from Shanghai and other jurisdictions of China were contacted to participate in in-depth qualitative interviews between October 2017 and August 2018. Participants were asked about their perception of the HepE vaccine roll-out. Codes were initially based on the structure of the questionnaire. Subsequently, similar ideas were further developed into themes based on what was present in the transcript data. Thirty-five individuals participated. Major topics of discussion included (1) clarifying the roles and responsibilities of private and public institutions in promoting and marketing the HepE vaccine, (2) identifying what methods of promotion were most efficient, and, (3) endeavoring to formulate a reasonable and realistic goal, if any, for HepE prevention and control in China. Participants emphasized that public sector sources can be trusted sources of information (although the private vaccination company can also be useful in disseminating information) and social media such as WeChat can be good ways to disseminate articles (although netizens may be worried about the spread of fake news). Vaccine promotion is restrained given limited levels of knowledge in the government, hospitals, and public health vaccination centers. Successful promotion and use of this vaccine in China, even in limited settings (for instance, certain workplaces, or certain groups) could provide additional information on long-term safety and could promote its adoption in other regions of the world where HepE has high morbidity among pregnant women and other populations. [ABSTRACT FROM AUTHOR]

Conventional wisdom advises keeping windows and doors closed in air-conditioned or mechanically-ventilated space. However, this guideline often proves challenging in high-occupancy offices, where the constant influx and egress of individuals, coupled with a strong inclination toward open windows, trigger occupant-induced ventilation (OV) that can affect indoor air quality (IAQ) and energy consumption. To address this, we explored using portable air cleaners (PACs) as a cost-effective ventilation strategy to replace mechanical ventilation (MV) while maintaining IAQ and respecting occupant freedom. We conducted a single-blind trial in a 100 m2 office in Shanghai from December 2020 to March 2021, measuring 857 h of indoor and outdoor temperatures, CO 2 and PM 2.5 concentrations, and occupant behaviors. We obtained 618 valid subjective responses and conducted a 14-day test to measure possible by-products, such as O 3 , formaldehyde, and VOCs, during the operation of PACs. The results showed that, first, although MV achieved 2–3 times higher air change rates than PACs, indoor CO 2 concentrations remained below 1000 ppm, the commonly accepted threshold, using PACs in the presence of OV. Second, PACs effectively reduced PM 2.5 levels during outdoor PM 2.5 peaks. Third, occupants' perceived IAQ did not differ between the use of PACs and MV (p >0.05), although individuals with PACs in the afternoon reported slightly increased sleepiness (p <0.05). Fourth, in the presence of OV, PACs demonstrated significant energy-saving potential in improving IAQ. Our study showed PACs can be a cost-effective method to replace MV while maintaining IAQ and preserving occupant freedom. • Deploy portable air cleaners (PACs), enabling window and door opening by occupants. • A randomized, single-blind trial was conducted for two winters in an open office. • PACs can control indoor PM 2.5 in the presence of occupant-induced ventilation (OV). • Indoor CO 2 concentrations remained below 1000 ppm using PACs due to OV. • Measurements confirmed low risks associated with by-products of PACs. [ABSTRACT FROM AUTHOR]

Air pollution in transportation cabins has recently become a public concern. However, few studies assessed the exposure levels of suspected air pollutants including Volatile Organic Compounds (VOCs). This paper studied the exposure levels of in-carriage VOCs (benzene, toluene, ethylbenzene, xylene, styrene, formaldehyde, acetaldehyde, acetone and acrolein) in Shanghai, China and estimated the health risk in different conditions. The results indicated that VOCs concentrations in metro carriages varied from different train models, due to the difference in carriage size and ventilation system. The concentrations of aromatic VOCs in old metro carriage were 1–2 times higher than the new ones, as better paintings were used in new trains. Poor air circulation and ventilation in the underground track was likely to be the cause of higher VOCs levels (~ 10%) than the above-ground track. Lower aromatic compounds levels and higher carbonyls levels were observed in metro carriages at suburban areas than those at urban areas, likely due to less aromatic emission sources and more carbonyls emission sources in suburban areas. Acetone and acrolein were found to increase from 7.71 to 26.28 μg/m 3 with number of commuters increasing from 40 to 200 in the carriages. According to the acceptable level proposed by the World Health Organization (1 × 10 − 6 –1 × 10 − 5 ), the life carcinogenic risk of commuters by subway (8.5 × 10 − 6 -4.8 × 10 − 5 ) was little above the acceptable level in Shanghai. Further application of our findings is possible to act as a reference in facilitating regulations for metro systems in other cities around world, so that in-carriage air quality might be improved. [ABSTRACT FROM AUTHOR]