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As a fullerene derivative, IC70BA is widely used in the ternary organic solar cells (TOSCs) to increase the open circuit voltage (Voc) of the devices. Unfortunately, most of the literature shows that IC70BA will lead to a reduction in the short-circuit current density (Jsc) and fill factor (FF). In this work, IC70BA is added to the PTB7:PC70BM binary system to form the ternary system, which is composed of one donor and two fullerene acceptors. Surprisingly, the addition of IC70BA does not immediately lead to a decrease in Jsc and FF. In fact, the appropriate weight ratio of IC70BA in fullerenes can simultaneously increase the Voc, Jsc, and FF of the TOSCs. The synergistic optimization of the surface and bulk morphology of the ternary active layer suppresses the attenuation of Jsc and FF. The smooth surface and suitable phase separation size effectively guarantee the separation, transport and extraction of the charge. Moreover, the addition of IC70BA can significantly improve the hole transport capacity of the active layer, and the optimal hole mobility is 5.13 – 10”4 cm2V–1S–1. Finally, the TOSCs with 10% weight ratio of IC70BA gives the optimal PCE of 9.24% and ideality factor of 2.3.

In this work, UV light activated multi-cycle photoelectric properties of TiO2 and CdS/TiO2 films in formaldehyde were researched. TiO2 film was prepared by screen printing, CdS/TiO2 compounded film was synthesized by SILAR method. XRD and FE-SEM was used to characterize the TiO2 and CdS/TiO2 samples. Multi-cycle photoelectric properties of TiO2 and CdS/TiO2 with uv light on and off were evaluated by testing the photocurrent. On one hand, under the same bias voltage, CdS/TiO 2showed a higher photocurrent than that by TiO2. The reason for this result should be ascribed to the compounded structure in CdS/TiO2, with which the separation and transfer of photogenerated electron-hole pairs could be improved. On the other hand, with the testing cycle number increased, the photocurrent amplitudes of TiO2 and CdS/TiO2 increased. These results suggested that the time to reach a stable photocurrent value for TiO2 and CdS/TiO2 is much longer than one cycle time (300 S). To illustrate the increased photocurrent amplitude value cycle by cycle, the photocurrent of CdS/TiO2 to a much longer time (more than 4000 seconds) was also tested. To explain these results, corresponding possible illustrations were presented.

The performances of the organic solar cells (OSCs) largely depends on the selection and preparation of the electron transport layer (ETL). In this paper, the uniform and compact Ge nanoparticles (NPs) film was fabricated by using the plasma enhanced chemical vapor deposition (PECVD) method at room temperature. The Ge NPs film is formed by close packing of amorphous Ge particles with an average diameter of 6.05 nm, and the film shows a fairly smooth surface with a root-mean-square (RMS) roughness of 0.6419 nm. The results shows that Ge NPs film exhibits n-type characteristics, and the longitudinal conductivity of the film is 1.90 × 10−5 S/cm, which is better than that of the ZnO NPs film. The excellent longitudinal charge transport characteristics is attributed to the existence of the columnar structures in the Ge NPs. In addition, the Ge NPs film shows a visible light transmittance comparable to that of the ZnO NPs film. More importantly, the energy levels of the Ge NPs film meets the requirements of the PTB7:PC70BM OSCs for the ETL, and the devices with the Ge NPs ETL shows the power conversion efficiency (PCE) of 7.38%. The characteristic of room temperature preparation make the Ge NPs ETL may become a reliable choice for the flexible devices in the near future.

Free-standing films based on MnO2@multi-walled carbon nanotubes (MWCNTs)@Polypyrrole (PPy) have been fabricated for aqueous zinc-ion batteries. A simple hydrothermal method was adopted to synthesize ß-MnO2 nanowires. PPy coated the ß-MnO2 nanowires@MWCNTs composite by an in-situ polymerization process. Free-standing films of ß-MnO2@MWCNTs@PPy composite were prepared by a convenient vacuum-assisted filtration. A zinc-ion battery is fabricated with a zinc foil anode and a ß-MnO2@MWCNTs@PPy composite cathode. The Zn//ß-MnO2@ MWCNTs@PPy system in ZnSO4@MnSO4 aqueous electrolyte exhibits high electrochemical performances, such as an initial capacity of 258.5 mAh g-1 at 0.2 A g-1, and about 74.6% retention after 100 cycles with near 100% Coulombic efficiency. The strategy of conductive polymer coating makes the technology of rechargeable zinc-ion batteries (ZIBs) very promising and provides opportunities of organic-inorganic composite materials for energy storage applications.

UV light driven photoelectric properties of ZnO film to humidity were researched. ZnO film was prepared through the method of screen printing sustained on Al2O3 substrate. ZnO was characterized by XRD, FE-SEM and EDX. The time-dependent UV light driven photoelectric properties of ZnO were investigated by exposing it to different bias voltages and different relative humidity (20% RH, 40% RH, 60% RH and 80% RH). On one hand, the photoelectric properties of ZnO increased with the augmenting of bias voltage, which shows that a higher bias causes more separation of carriers. On the other hand, the photocurrent decreased with the increase in relative humidity, which shows that bigger humidity results in smaller photoelectric property. To discuss these results, corresponding possible illustrations for the photoelectric properties under different conditions were proposed.

Associations of household airborne fungi with allergies in childhood were inconsistent in the epidemiologic studies. During 2013–2014, we conducted a case-control study (phase two), which was nested in a cross-sectional study (phase one) during 2011–2012 in Shanghai, China. We inspected indoor air quality of 454 residences for 5–10 years old children. We defined cases as those children who were reported illnesses in the questionnaire of phase one or phase two and defined controls as those children who were not reported illnesses in both phases. A total of 436 living rooms and 445 bedrooms had valid data of household airborne fungi, and their mean concentrations were 301 cfu/m3 and 310 cfu/m3, respectively. In the multiple logistic regression analyses with adjusting for potential confounders, most associations of 16 studied illnesses with airborne fungi concentration were not statistically significant. Taking children in the 1st quartile that was stratified according to airborne fungi concentration in the living room as reference, only children in the 3rd quartile were significantly associated with a higher odd of lifetime-ever ear infections (adjusted OR, 95% CI 3.05, 1.29–7.21), and children in the 4th quartile were significantly associated with a higher odd of lifetime-ever wheeze (2.72, 1.28–5.75); but children in the 3rd quartile (0.33, 0.17–0.68) and in the 4th quartile (0.47, 0.23–0.97) were significantly associated with a lower odd of rhinitis in the past 12 months prior to the home inspection. Our results indicate that exposures to indoor airborne fungi in low concentrations seemingly have no significant impacts on the risks of most allergic and airway illnesses in childhood. Since families with sick participants might pay more attention to improve indoor air quality, effects of “avoidance behavior” on associations between indoor pollutants and childhood health should be considered in the data analysis and design of the nested case-control study.

During 2010-2012, we surveyed 40,010 3- to 6-year-old children in seven Chinese cities (Beijing, Taiyuan, Urumqi, Shanghai, Nanjing, Changsha, and Chongqing). Their parents reported information on household renovation, including the timing of renovation and the choice of materials for walls and floors in the child's room, and the incidence of their child's rhinitis. Multivariate and two-level (city-child) logistic regression analyses yielding adjusted odds ratios (AOR) with 95% confidence intervals were performed. Sensitivity analyses stratifying data for location and economic level were also performed. About 48.0% of the children had ever had allergic rhinitis, 41.2% had current allergic rhinitis, and 9.0% had had doctor-diagnosed rhinitis. Exposure to household renovation during early lifetime (birth to 1-year-old) had an AOR of 1.43 (1.04-1.9) for allergic rhinitis. The incidence of allergic rhinitis was significantly different in children exposed to different floor and wall covering materials. Floor or wall covering material composed of organic materials significantly increased the risk of childhood allergic rhinitis compared with tile flooring or lime wall covering. Oil paint had an AOR of 1.66 (1.28-2.14) for diagnosed rhinitis compared with lime wall covering. Adding new furniture the year before pregnancy was associated with an AOR of 1.18 (1.10-1.27) and 1.18 (1.11-1.25) for lifetime and current rhinitis. Solid wood or tiles/ceramic as floor materials, and using wallpaper, oil paint, or emulsion panels as wall materials were risk factors for doctor-diagnosed rhinitis. Sensitivity analyses showed that children living in southern or higher economic level China cities were more likely to have allergic rhinitis with household renovation.

The use of occupant-exhaled CO2 as the tracer gas enables the actual indoor infiltration rate to be measured, but the number and location of measuring points have a great impact on the accuracy of the results. This paper compares the experimental results from two tracer gas measurement techniques, decay with SF6 and constant injection with CO2 (exhaled by occupant). The results show a deviation of –9.0 to 7.4% between these two methods. This paper compares the result of this study with previous ones, and it confirmed that the CO2 method is an effective technique to calculate the infiltration rate in a room with a certain air volume when one measuring point is provided, and this is more accurate with good mixing of the indoor air. The impact of the measurement duration and distribution of indoor air on the measurement accuracy are also analysed. It is found that an extended monitoring period can reduce the impact of indoor air distribution. In actual measurements in residential building, it is recommended to select the data after occupants have been in the room for half an hour and to take measurements over 1 h after that. Practical application: Accurate air change per hour (ACH) is beneficial to the study of building energy consumption and indoor air quality. This paper explores the effectiveness of CO2 method, which provides useful reference for the large sample measurements of infiltration rates in residential buildings.

Ternary blend polymer solar cells (TPSCs) comprising one donor and two fullerene acceptors is efficient method for improving the power conversion efficiency (PCE). In this paper, the PTB7-Th-based TPSCs which is incorporating PC70BM and PC60BM as mixed acceptors are fabricated and investigated. Impressively, the remarkable self-assembled nano-ridged (SANR) structures are discovered in the active layer with the weight ratio of 50% PC60BM in fullerenes. Thanks to the enlarged interface area, enhanced light absorption and balanced carrier transport, the PTB7-Th:PC70BM:PC60BM TPSCs with the SANR active layer gives an optimal PCE of 9.68%. In addition, it is worth emphasizing that by combining the textured-ZnO with the SANR active layer, a double ridge superimposed system (DRSS) with broad spectrum light trapping characteristic is constructed, which can further enhance the light absorption of the devices. Finally, benefiting from the further increase in short circuit current density (Jsc), the PTB7-Th:PC70BM:PC60BM TPSCs with the DRSS gives an optimal PCE of 10.68%. This work provides a feasible ternary strategy to increase the devices performances and is proved be a simple and efficient strategy for fabricating PTB7-Th:PC70BM:PC60BM TPSCs with SANR active layer.

China's profoundly rapid modernization in the past two decades has resulted in dramatic changes in indoor environmental exposures. Among these changes, exposure to phthalates has attracted increasing attention. We aimed to characterize indoor phthalate exposure and to estimate the disease burden attributable to indoor phthalate pollution from 2000 to 2017 in China. We integrated the national exposure level of indoor phthalates from literature through systematic review and Monte Carlo simulation. Dose-response relationships between phthalate exposure and health outcomes were obtained by systematic review and meta-analysis. Based on existing models for assessing probabilities of causation and a comprehensive review of available data, we calculated the disability-adjusted life years (DALYs) among the general Chinese population resulting from exposure to indoor phthalate pollution. We found that DnBP, DiBP, and DEHP were the most abundant phthalates in indoor environments of residences, offices, and schools with medians of national dust phase concentration from 74.5 µg/g to 96.3 µg/g, 39.6 µg/g to 162.5 µg/g, 634.2 µg/g to 1,394.7 µg/g, respectively. The national equivalent exposure for children to phthalates in settled dust was higher than that of adults except for DiBP and DnOP. Dose-response relationships associated with DEP, DiBP, DnBP, BBzP, and DEHP exposures were established. Between 2000 and 2017, indoor phthalate exposure in China has led to 3.32 million DALYs per year, accounting for 0.90% of total DALYs across China. The annual DALY associated with indoor phthalate pollution in China was over 2000 people per million, which is about 2~3 times of the DALY loss due to secondhand smoke (SHS) in six European countries or the sum of the DALY loss caused by indoor radon and formaldehyde in American homes. Our study indicates a considerable socioeconomic impact of indoor phthalate exposure for a modernizing human society. This suggest the need for relevant national standard and actions to reduce indoor phthalate exposure.

In this work, to research the photoelectric responses to humidity using a semiconductor film, an ultraviolet (UV) light induced device has been investigated on SnO₂ film at room temperature. Screen printing method was used to prepare SnO₂ film on the Al₂O₃ substrate. The crystalline structure and morphology of SnO₂ was characterized with XRD and FE-SEM. The UV light induced photoelectric responses of SnO₂ to a constant humidity (20% RH) were evaluated firstly under four different bias voltages. At 2 V bias voltage, the photocurrent amplitude reaches 4.58

During the process of the low-temperature solution fabrication, it always leads to high defects density at the grain boundaries and the interfaces, which are great barriers toward excellent solar cells. Different polar molecules of solvents are brought in to modify the surface composition by tuning the nucleation densities to obtain perovskite films with high crystallization quality. In this work, with efficiently exchanging intramolecular mechanism, high-quality MAPbI3-based perovskite films had been conveniently fabricated. Two kinds of polar molecules of dimethyl sulfoxide (DMSO) and N-methyl-2-pyrrolidone (NMP) were added to the dimethylformamide (DMF) solvent to result in perovskite films with high quality. As a result, the device with NMP solvent treatment outputs improved efficiency of 18.5% at the short-circuit current (Jsc) of 23.3 mA cm–2, with an open-circuit voltage (Voc) of 1.075 V and a fill factor of 77.1% under standard AM 1.5 solar illumination. This method of solvent engineering might provide a convenient way for the application of perovskite-based photovoltaic devices.

We surveyed 40 010 three- to six-year-old children in seven Chinese cities (Beijing, Taiyuan, Urumqi, Shanghai, Nanjing, Changsha, and Chongqing) during 2010-2012 so as to investigate possible links between home renovation and childhood eczema. Their parents responded to questions on home renovation and childhood eczema. Multivariate and two-level (city-child) logistic regression analyses yielding odds ratios with 95% confidence intervals were performed. Sensitivity analyses stratifying data for region, climate, and income level were also performed. The prevalences of childhood eczema in children with different floor and wall covering materials were significantly different and were significantly higher with home renovation during early lifetime. Exposure to synthetic materials significantly increased the risk of childhood eczema by 20%-25%. The risks (AOR, 95% CI) of current eczema among children in families with solid wood flooring and oil paint wall covering were 1.25 (1.04-1.49) and 1.35 (1.14-1.60), respectively. Home renovation during pregnancy was related to children's lifetime and current eczema.

In 2013–2014, we carried out a case-control study in Shanghai, China and collected dust samples from 453 children's beddings (pillow and mattress). Here we investigated associations of bed dust mites (Der p 1 and Der f 1) with childhood health outcomes. These dust mites were analyzed by enzyme-linked immune-sorbent assay (ELISA). The child's health outcomes were reported by parents. Der f 1 concentration among cases were significantly higher than controls for current rhinitis and eczema, but Der p 1 concentration among cases were significantly lower than controls for lifetime-ever croup and asthma. In the multivariate logistic regression analyses, Der p 1 (increment: 0.98 μg/g) and Der f 1 (0.28 μg/g) were associated with the increased odds of dry cough (Der p 1: adjusted odds ratio (AOR), 95% confidence interval (CI): 1.48, 1.01–2.17, p-value: 0.047; Der f 1: 1.52, 1.09–2.12, 0.013) and rhinitis (Der p 1: 1.44, 1.05–1.97, 0.025; Der f 1: 1.25, 0.98–1.60, 0.078). Der f 1 (increment: 0.28 μg/g) had significant associations with the decreased odd of lifetime-ever asthma (OR, 95%CI: 0.75, 0.58–0.97). Significantly higher proportions of families with habits for frequently bed-cleaning were found among cases than among controls according to the most studied illnesses. Our results indicate that exposure to bed dust Der p 1 and Der f 1 could be risk factors for childhood allergic symptoms. Avoidance behaviors with respect to household dust mites among families with case children perhaps mask the real associations of these dust mites with childhood health outcomes in the retrospective case-control study.

The presence of self-assembled nano-ridged (SANR) structures in PTB7-Th:PC70BM:PC60BM ternary organic blend film with the specific component ratio was experimentally clarified, and the light-trapping effect of the SANR structures was demonstrated. On this basis, the light-trapping characteristics of the PTB7-Th:PC70BM:PC60BM ternary blend film with the SANR structures were investigated by using the finite-difference time-domain (FDTD) algorithm. The results showed that the SANR structures have a light-trapping effect, which can effectively reduce the transmittance and reflectance of the incident photons at the specific wavelengths and thus exhibit stronger photon absorption, especially for the photons in the wavelength range of 550–650 nm. The light-trapping effect of the SANR structures does not depend on the direction of photon incidence, and the active layer traps the photons incident from both its top and bottom. The dimensional variation of the SANR has a significant effect on the light-trapping characteristics of the active layer, and the effect caused by the height variation is overwhelmingly superior compared with that of the width variation. In addition, the higher the density of the SANR, the more significant the light-trapping effect of the active layer. This work provides a theoretical basis for the further experimental enhancement of the photon absorption capacity of the PTB7-Th:PC70BM:PC60BM active layer with SANR structures.

In this work, UV light activated multi-cycle photoelectric properties of TiO₂ and CdS/TiO₂ films in formaldehyde were researched. TiO₂ film was prepared by screen printing, CdS/TiO₂ compounded film was synthesized by SILAR method. XRD and FE-SEM was used to characterize the TiO₂ and CdS/TiO₂ samples. Multi-cycle photoelectric properties of TiO₂ and CdS/TiO₂ with uv light on and off were evaluated by testing the photocurrent. On one hand, under the same bias voltage, CdS/TiO ₂showed a higher photocurrent than that by TiO₂. The reason for this result should be ascribed to the compounded structure in CdS/TiO₂, with which the separation and transfer of photogenerated electron-hole pairs could be improved. On the other hand, with the testing cycle number increased, the photocurrent amplitudes of TiO₂ and CdS/TiO₂ increased. These results suggested that the time to reach a stable photocurrent value for TiO₂ and CdS/TiO₂ is much longer than one cycle time (300 S). To illustrate the increased photocurrent amplitude value cycle by cycle, the photocurrent of CdS/TiO₂ to a much longer time (more than 4000 seconds) was also tested. To explain these results, corresponding possible illustrations were presented.

As a fullerene derivative, IC

A building-integrated photovoltaic-thermal (BIPVT) system integrates building envelope and photovoltaic-thermal collectors to produce electricity and heat. In this paper, the electrical and thermal performance of roof-based BIPVT systems developed in the recent two decades and their effects on heating and cooling load of the building are reviewed. According to the use of thermal energy from the photovoltaic (PV) panels, the roof-based BIPVT are classified into three classes: cooling of PV, air heating, and water heating. Each class is further divided into several types according to the designs of the integrated PV roofs. Compared with BIPV systems, the total efficiency of most BIPVT systems is significantly improved. However, the decrease in electricity output and adverse impact on the indoor environment is also found for some designs of BIPVT systems in some climates. The advantages and disadvantages of various designs are discussed. Issues to be further studied in the future are also provided in this review.

It’s inconsistent about associations of early exposures to outdoor air pollutants with allergies and airway diseases in childhood. Here, we investigated associations of prenatal and postnatal exposures to outdoor nitrogen dioxide (NO2), sulphur dioxide (SO2), and PM10 (particulate matter with an aerodynamic diameter ≤ 10 μm) with asthma, wheeze, hay fever, rhinitis, pneumonia, and eczema in childhood. We surveyed 3,177 preschoolers who never change residences since birth in Shanghai, China. Parents reported information regarding children’s health status. Daily-averaged concentrations of these pollutants in the children’s gestation and in the first year of lifetime for district where children lived were collected by Shanghai Environmental Monitoring Center. After adjusting for covariates, exposures to higher level of NO2 during different trimesters of gestation and of the first year of lifetime had significant associations with the increased odds of asthma, hay fever, rhinitis, pneumonia, and eczema in childhood. Associations of NO2 exposures in the early trimesters of gestation and of the first year of lifetime with pneumonia were stronger than in the later trimesters, whereas associations of NO2 exposures in the early trimesters with hay fever and eczema were weaker than in the later trimesters. Our results indicated that prenatal and postnatal exposures to outdoor NO2 could be risk factors for allergies and airway diseases in childhood. Both dose and duration were related with the influence degree of early NO2 exposure on childhood allergies and airway diseases.

Numerous research reports have demonstrated that the supply air volumes of cleanrooms areusuallyover-designed to satisfy air cleanliness classes, which may lead to enormous energy waste. In this study, five well-recognised international mathematical models for calculating cleanroom particle concentration were analysed, which are all based on uniform particle distribution in the cleanroom, indoor particle conservation, and mass airflow balance, and an improved and more general model has been established for calculating the minimum air change rates according to the expected air cleanliness class. Following the introduction of non-dimensional concentration correction factors, based on the least-squares method, the average relative error between the model-predicted and measured particle concentration is approximately 13.5%. Based on the improved model with correction factor, the test results demonstrate that the particle concentration depends mainly on the air change rate, particle emission rate and return airflow patterns, among others. When the air change rate per hour and ratio of particle concentrations between the return airflow and room average were varied from 40 h−1 to 120 h−1 and 0.7–1.3, respectively, the concentration consequently decreased by approximately 65% and 46%. The particle deposition caused by gravity can be neglected for small particles.

In order to investigate the relationship between outdoor air pollution and sick building syndrome (SBS) symptoms, the CCHH (China, Children, Home, Health) group in Shanghai conducted a cross-sectional survey on the current incidence of SBS symptoms among residents in five districts of Shanghai during April 2011–April 2012. It also collected the related outdoor air pollutants data from Shanghai environmental monitoring center (SEMC), including nitrogen dioxide (NO2), sulfur dioxide (SO2) and particles with aerodynamic diameter less than 10 µm (PM10). The logistic regression models were used in this paper to study the associations between air pollutants and SBS symptoms. Results were found that the daily mean concentrations of NO2 and SO2 met standard requirement, but that of PM10 exceeded the limit values of the standard in China during this survey. The significant differences were found between the pollutants concentration in urban and suburban area. In addition, the incidences of three categories of SBS symptoms among residents were 79.1% for general symptoms (GS), 65.2% for mucous membrane symptoms (MS) and 35.7% for skin symptoms (SS), respectively. Multiple logistic regression analysis by two case studies illustrated that three outdoor air pollutants, both their concentration quartiles and equal increment, were all associated to and taken as the risk factors for SBS symptoms, for GS ORNO2 = 1.62 (1.18–2.22), MS OR NO2 = 1.58 (1.21–2.06) and SS OR PM10 = 1.21 (1.09–1.35). Furthermore, the new pollutants expressed as the mixtures of their combination were also significantly associated with part of the SBS symptoms. The synthetic air quality indexes of all surveyed residents were calculated as III-level, which represented mild pollution. Therefore, it would be an effective way to decrease the incidence of SBS symptoms in residence to reduce the outdoor air pollution and control the penetration from outdoor to indoor environment.

Stratified air-conditioning (STRAC) has been deployed in large space buildings to achieve vertical thermal stratification with significant energy-saving potential. This research focuses on two typical STRAC systems: floor-level sidewall air-supply system (FSAS) and nozzle sidewall air-supply system (NSAS). By employing experiment and CFD methods, airflow pattern and heat transfer between the unoccupied and occupied zone under the two air supply systems are investigated in a reduced-scale laboratory. The geometric models of the prototype building, with a geometrical scaling factor of 4:1, are established according to similarity principles and studied by CFD simulation. The results demonstrate that the two scales have similar indoor thermal performances. The numerical simulation results of the prototype building provide and compare commonly used inter-zonal heat transfer coefficients of actual large space buildings with the two typical STRAC systems. For FSAS, heat conduction caused by temperature gradient dominates the inter-zonal heat transfer. In NSAS, both heat conduction due to temperature gradient and heat convection due to airflow contributes equally to this heat transfer. The inter-zonal heat transfer coefficient Cb is affected by the airflow pattern and zonal division, and closely associated with local turbulence intensity.

Exposure of phthalate has adverse effects on child health. Currently, the field measurement on PAEs concentration in children’s bedrooms were limited, and the test of PAEs is laborious. Based on the data of home detection in 454 residences from March 2013 to December 2014 in Shanghai, the association of PAEs in children's bedroom and building characteristics, residents’ lifestyle and indoor environment characterization were built by Spearman correlation. According to the Spearman correlation coefficient method, the concentration of PAEs, such as residential area was significantly correlated with DMP, BBP and DiBP in children’s bedroom (sig 0), and the use of chemicals was significantly associated with DEP and DiBP in children’s bedroom (sig 0). Then a gradient-boosting decision tree model with higher prediction accuracy is established. The influencing factors of the studied PAEs were determined by comprehensive consideration of the current study and literature review. 11 influencing factors of PAEs concentrations from three aspects were finally established in this study. The training model of GBDT has a reasonable accuracy( R2>0.9). This paper provides a reference for the prediction of PAEs concentration in the residential bedroom and the influence degree of influencing factors.

Few studies pay attention to the possible associations between indoor VOCs and childhood asthma in Shanghai considering the effect of household ventilation. From March 2013 to December 2014, we collected air samples from 358 children's bedrooms in Shanghai, China. Information on childhood asthma, environmental exposures, and lifestyle behaviors was collected. Two-sample of Mann-Whitney U test, bivariate logistic regressions, and multiple logistic regression were used to obtain the association between VOCs and childhood asthma. Association analysis stratified by frequency of window opening during night was conducted to explore its possible effect on the target association. High concentrations of toluene and dodecane were significantly associated with childhood wheeze, and a high concentration of toluene was significantly associated with diagnosed asthma. In the bedrooms with low frequency of window opening during night, high concentrations of toluene, dodecane, and TVOC were significantly associated with childhood wheeze, and a high concentration of toluene was significantly associated with diagnosed asthma. Our results indicate that exposure to VOCs may be a risk factor for childhood asthma, especially in the bedrooms with poor ventilation during night. Family avoidance behaviors of household ventilation should be considered in the study of associations of household VOCs with childhood asthmatic symptoms.

Household dust mites (HDMs) are the important allergens causing allergic diseases in children. A predictive model can help us understand the concentration of HDMs in different areas of China to better prevent and control this kind of allergen. This study used 454 household inspection samples in childrens’ room obtained from China, Children, Homes, Health (CCHH) phase 2 study, conducted during 2013-2014. Spearman correlation and multiple logistic regression were used to explore the influencing factors of HDMs concentrations, by comprehensively considering residents’ lifestyle, building characteristics, environmental exposure, especially dampness-related exposures. This study used the Gradient Boosting Decision Tree(GBDT) algorithm to build the prediction model. The data from CCHH were used to established the prediction model. It was found that there were some differences in the influencing factors between two types of HDMs. The concentration of HDMs were found a significant correlation (p2>0. 9). This paper provides a reference for predicting the HDMs concentrations in children's bedrooms and the influence of the influencing factors.

In this paper, the CO2 (carbon dioxide) exhaled by indoor occupants was used as the tracer gas, and the variation of indoor CO2 concentration in the whole day was observed. Among the 454 samples, 114 and 345 valid samples were screened out which can be used to calculate the daytime and night ventilation rate by the tracer gas method through the sectioning method. The results indicated that seasonal differences in daytime average ventilation are greater than night average ventilation. The highest daytime- average ventilation was found in autumn, next was summer, there was the lowest ventilation in winter. According to the necessary fresh air rate when sleeping at night, night average ventilation rate of 30.1% of samples met the standard. The ventilation rates of different building characteristics were analyzed, residential location, construction age, living floor, room size, window structure, indoor dampness, and window opening habits were all included. The results revealed that the window opening habits was the most significant factor for natural ventilation. Both daytime and night average ventilation rate are basically in the ratio of 2:1 when the windows are opened and closed. moreover, there was higher impact of outdoor climate on daytime average ventilation when window was closed. Significant impact of window structure and indoor dampness on night average ventilation was observed when window was opened. Present study proposed the measurement and determination methods of ventilation when daytime activities of occupants were happened

With the improvement of people's requirements for living environment, the effect of indoor radon radioactivity on health has been widely concerned. In this paper, taking a university in Shanghai as an example, indoor radon concentration and its related environmental parameters were measured in some of its rooms to understand the level of indoor radon concentration on its campus. The results showed that the average concentrations of student dormitory, office buildings, and academic buildings were 14.79±9.15 Bq/m3,22.67±5.72 Bq/m3, and 12.55±6.71 Bq/m3 respectively. Indoor radon was positively correlated with indoor temperature and humidity, and ventilation was also an effective method to reduce indoor radon.

Dampness-related exposures have been widely discovered in household, which are associated with childhood health. This study employed the Back-Propagation (BP) neural network to develop prediction models of overall dampness evaluation based on the on-site dampness inspection in 454 families. The trained models were then used to predict the overall dampness exposure in 15,266 families with five parent-reported dampness-related indicators. Two indices, including the overall-dampness- exposure-based (ODEB) score and combination-of parent-reported- based (CPRB) score, were introduced to reflect the household dampness exposure in Shanghai, and were used to build the relationship with different childhood respiratory diseases and allergies. The results indicated that the trained model of BP neural network had a reasonable accuracy with the coefficient of determination R2 greater than 0.5, and the standard deviation ratios were approaching 1.0. Both the ODEB score predicted by trained model and CPRB score were developed based on parent reported dampness indicators in the cross-sectional survey, and were significantly associated with childhood respiratory diseases after adjusting the confounders (AOR >1.3, p 0). Exposure-response relationships were also found between the dampness exposure indices and health outcomes. A continuous dampness evaluation index with a reasonable accuracy was proposed based on BP neural network prediction of on-site dampness scoring, which was consistent with the CPRB score, showing an exposure-response relationship with childhood diseases. These findings provide us an approach to predict the household dampness and its related adverse health outcomes.

Several studies have reported that certain aspects of the household environments are associated with adverse birth outcomes, but associations have been inconsistent. Few of these studies have been conducted in China. During 2011-2012, we conducted a retrospective cross-sectional study and collected 13,335 parents-reported questionnaires for 4-6-year-olds children in Shanghai, China. We investigated associations of household environmental factors (environmental tobacco smoke (ETS), cooking fuel, dampness, pet-keeping, and home renovation) during gestation with preterm birth (PTB, gestational age

The urbanization and industrialization in China is accompanied by bad air quality, and the prevalence of asthma in Chinese children has been increasing in recent years. To investigate the associations between ambient PM2.5 levels and asthmatic and allergic diseases or symptoms in preschool children in China, we assigned PM2.5 exposure data from the Global Burden of Disease (GBD) project to 205 kindergartens at a spatial resolution of 0.1° × 0.1° in six cities in China (Shanghai, Nanjing, Chongqing, Changsha, Urumqi, and Taiyuan). A hierarchical multiple logistical regression model was applied to analyze the associations between kindergarten-level PM2.5 exposure and individual-level outcomes of asthmatic and allergic symptoms. The individual-level variables, including gender, age, family history of asthma and allergic diseases, breastfeeding, parental smoking, indoor dampness, interior decoration pollution, household annual income, and city-level variable-annual temperature were adjusted. A total of 30,759 children (average age 4.6 years, 51.7% boys) were enrolled in this study. Apart from family history, indoor dampness, and decoration as predominant risk factors, we found that an increase of 10 μg/m3 of the annual PM2.5 was positively associated with the prevalence of allergic rhinitis by an odds ratio (OR) of 1.20 (95% confidence interval [CI] 1.11, 1.29) and diagnosed asthma by OR of 1.10 (95% CI 1.03, 1.18). Those who lived in non-urban (vs. urban) areas were exposed to more severe indoor air pollution arising from biomass combustion and had significantly higher ORs between PM2.5 and allergic rhinitis and current rhinitis. Our study suggested that long-term exposure to PM2.5 might increase the risks of asthmatic and allergic diseases or symptoms in preschool children in China. Compared to those living in urban areas, children living in suburban or rural areas had a higher risk of PM2.5 exposure.

During March 2013–December 2014, we conducted a field study in Shanghai, China. A total of 409 children's bedrooms had valid data for formaldehyde which was continuously measured for 24 h. The daily 24 h-averaged and night 6 h-averaged (00:00–06:00) concentrations were 21.5 μg/m3 and 22.2 μg/m3, respectively. Bedrooms with mechanical ventilation had lower formaldehyde concentrations than those with natural ventilation. In the multiple logistic regression analyses, compared to children in the first quartile of 24 h-averaged formaldehyde, children in fourth quartile had significantly lower odds of lifetime-ever food allergy (adjusted odds ratio (OR), 95% confidence interval (CI): 0.39, 0.16–0.97) and current rhinitis (0.39, 0.18–0.86), but children in the third quartile had significantly higher odd of current common cold (≥3 times) (2.42, 1.02–5.77). Among autumn-inspected children, formaldehyde exposure had significant associations with current common cold (≥3 times) (adjusted OR, 95%CI for 24 h-averaged: 4.88, 1.18–20.21 in increment of 11.7 μg/m3; for 6 h-averaged: 4.41, 1.07–18.19 in increment of 15.7 μg/m3). Significantly more families with case children used household mechanical ventilation and air cleaner than families with control children. Our results indicate that household formaldehyde exposure may increase the risk of childhood common cold. Since it is impossible that formaldehyde exposure in higher concentrations could decrease the risk of current rhinitis and other illnesses, we infer that those “negative” associations could be confounded by the potential behaviour changes for avoidance of household formaldehyde exposure among families with case children.

Few studies have estimated the effects of dampness-related exposures and its interaction effects with poor household ventilation on common colds of preschool children. During April 2011–April 2012, we conducted a cross-sectional survey on home environment and childhood health and collected 13,335 parents-reported questionnaires of 4–6 year-old children in Shanghai, China. In this paper, we investigated associations between the incidence and duration of common colds among these children during the past 12 months before the survey and frequency of opening windows, as well as household dampness-related exposures (indicated by six dampness indicators). Significantly higher incidence (≥3 times) and longer duration (≥2 weeks) of common cold were found among children with than without these dampness exposures (p-value, Highlights • The effects of home dampness and natural ventilation on childhood common cold is lacking and unclear. • Exposure to environment with any dampness indicator is a risk factor for common cold of preschool children. • The risk of common cold is higher in the environments with more dampness-related indicators. • Home dampness and household ventilation have both multiplication and addictive interaction effects on common cold. • Household ventilation can modify the negative effect of home dampness exposure on common cold.

In this work, photoelectric responses of nanocrystalline WO3 film to humidity under UV light irradiation were investigated. Nanocrystalline WO3 film with porous structure was prepared on Al2O3 substrate by the technology of screen printing and the subsequent heat treatment. The as-prepared nanocrystalline WO3 film was characterized with X-ray diffraction (XRD) and field-emission gun scanning electron microscopy (FE-SEM). The time-dependent photoelectric responses of nanocrystalline WO3 film were studied by exposing it to a wide humidity range of 20–80% relative humidity (RH) at room temperature under UV light irradiation. High performance photoelectric responses of nanocrystalline WO3 film to humidity were observed. To illustrate it, a possible explanation for the photoelectric responses to humidity was proposed. On the basis of the results, the high performance photoelectric responses of WO3 to humidity will provides a new insight into the design and fabrication of advanced photo-activated humidity sensors.

A series of calcium copper titanate (CaCu3Ti4O12, CCTO) samples are prepared by a citric acid sol–gel method and the effect of sintering conditions on microstructure, dielectric and nonlinear electrical properties are investigated in detail. Systematical characterizations by both X-ray diffraction and Raman spectra identify the component phases of sintered products, verifying the formation of single phased CCTO if suitable sintering temperature and durations are selected. Well crystallized grains with the size of several microns are attained for the samples sintered at 1020 °C for 5 h, will make a contribution to giant dielectric behavior, evidenced by the highest value of dielectric constant (e′ > 2.5 × 104) in the frequency range of 102 to 5 × 105 Hz. Dielectric spectroscopy measurements show similar dielectric dispersion for all the samples, which can be well interpreted by the interface polarization from grain boundaries and the bulk effect. Meanwhile, nonlinear electrical behaviors are observed for all the samples, attributing to the Schottky-like electrostatic barriers at the grain boundaries.