Studies show that user behaviours have not necessarily changed, despite the prevalence of water-efficient products in the market. One reason is because the technical emphasis for delivering the water use efficiency of products has focused on reducing the flow rate. Therefore, this study was undertaken to examine the physical parameters that define the technical efficiency of showerheads against the experiential performance (and therefore the satisfaction with the showerheads). These parameters were measured in a controlled laboratory environment and the findings were triangulated against user feedback from in-home trials. Synergies between the laboratory data and user feedback were found. Notably, it was found that water spray intensity, distribution, and temperature loss all impact the quality of showering experience. These factors also influence shower duration—and thus the volume of water used in the shower. Significantly, these technical metrics affected the overall experiential performance of such products from the users’ perspective. Therefore, the design of water-efficient showerheads, in addition to delivering water discharge savings, should avoid poor spray distribution, intensity, and heat retention. The implications of the findings are that water efficiency labelling and product standards should extend beyond the emphasis on limiting the flow rates—typically to 9 l per min for showerheads. This study shows good merit for including the spray intensity (pressure), distribution, and degree of heat loss, in addition to the discharge rate, as part of the performance and efficiency considerations of showerheads.

The GIS-based water quantity and water quality model is widely used to provide decision-making supports for water resource and water quality management. However, the existing integration patterns of GIS and model system mainly depend on data communication between themselves which may lead to low operating efficiency and time-consuming model setup. In this paper, a generalized data structure (dual object structure (DOS)) which can store the data of GIS objects and model objects together is proposed and realized for the first time, avoiding frequent data communication during the period of numerical simulation and result expression, realizing the fusion of GIS objects and model objects at the data structure level, improving the operating efficiency of the system. Finally, the water quantity and water quality modeling software (digital basin simulation system (DBSS)) based on DOS was developed by using C++ language. The software has been applied successfully in large-scale river basins of China, and one of the cases was demonstrated to show the application process and the outstanding results.

Environmental lead (Pb) exposure can induce dysbacteriosis, impair oral health, and is associated with the development of dental caries. However, the mechanism is unclear. The aim of this study was to explore the effects of Pb toxicity on oral antimicrobial activity in children in an e-waste area. Results showed higher blood Pb levels in e-waste-exposed group children, accompanied by decreased saliva SAG (salivary agglutinin) concentrations, increased peripheral WBC (white blood cell) counts and monocyte counts, and elevated peripheral monocyte percentage. LnPb (natural logarithmic transformation of blood Pb level) was negatively correlated with saliva SAG concentration, while positively correlated with peripheral monocyte percentage. Saliva SAG concentration played a complete mediating role in the correlation of LnPb to peripheral monocyte percentage. To our knowledge, this is the first study on the relationship of environmental Pb exposure and oral antimicrobial activity in children, showing that environmental Pb exposure may weaken oral antimicrobial activity through reducing saliva SAG concentration, which may raise the risk of oral dysbacteriosis and ultimately pathogen infection.

Net primary productivity (NPP) of terrestrial ecosystems is an important metric of ecosystem functioning; however, the understanding of response mechanism of NPP to influencing factors and driving mechanisms are still limited. In this study, taking Anhui province as an example, spatio-temporal changes of NPP and its response to influencing factors were investigated for evaluating the effects of climate change and land use and land cover change (LUCC) on regional NPP. The Carnegie–Ames–Stanford Approach (CASA) model was employed for NPP simulation by using the MODIS normalized difference vegetation index (NDVI) data and meteorological data over 2001–2016. Combined domestic LUCC, the spatiotemporal distribution pattern and dynamic change characteristics of NPP under a long time series and its response to climate factors and human activities were analyzed in the Anhui province. The results indicated that from 2001 to 2016, total NPP had a fluctuated and decreased trend with the variation range between 30.52 and 38.07 TgC in Anhui province. The multi-year average of total NPP was about 34.62 TgC. The highest value was in 2008 and the lowest value was in 2011. Among them, amount of forestland NPP was the most. The spatial distribution of NPP shows that the high value area was mainly distributed in southern Anhui mountain areas and western Anhui Dabie mountain areas; the lower value was distributed in the middle in the study area. The area of which the NPP showed a slight decrease and essentially unchanged accounted for 59.35% and 31.82%, respectively. In general, the correlation between vegetation NPP and temperature was greater than that between precipitation. The vegetations NPP of eight land use types were all positively correlated with temperature. However, the other seven types of land use were negatively correlated with precipitation except cultivated land. In the past 16 years, the decrease of cultivated land areas and the increase of urban and construction land areas contributed a lot to the decrease of vegetation NPP in Anhui province. The NPP changes of different land use types were closely related to climatic factors, land cover area, and vegetation types.

Based on the 1.5 °C temperature control target of the Paris Agreement, the two scenarios in this paper which are 1.5 degree scenario (1.5DS) and 2 degree scenario (2DS) aim to analyze the CO₂ emission space and power transition path constrains of the power sector in China. This paper then discusses the possible scenarios of 1.5DS and 2DS power planning schemes in 2050. The conclusions are as follows: (1) China’s electricity consumption saturation period will occur during the period of 2030–2040; (2) Driven by technology learning, the levelized cost of electricity (LCOE) of wind power will have obvious competitive advantages in 2020 and so does solar power in 2030. However, due to the impact of additional grid connection costs of new energy power, economic advantages can only be obtained in the power market after at least 10 years; (3) The installed capacity of coal power in 1.5DS and 2DS will peak in 2020, and CO₂ emissions will also peak in 2020, then it shows a trend of decreasing year by year. However, it should be noted that 1.5DS is with possibilities, but with enormous challenges as the same time; (4) Accelerating the green and low carbon transition of power sector must be gradually improving the power market and electricity price mechanism, providing a good transition environment for the power sector, developing emerging power technology, and promoting multi-energy complementary systems.

A low-cost Cr(III)-incorporated Zr(IV) bimetallic oxide (CZ) was synthesized by simple chemical precipitation method for removal of fluoride from contaminated water. The physicochemical properties of CZ before and after fluoride removal were established with several instrumental techniques such as TEM with elemental mapping, SEM with EDX, XRD, IR, XPS, zeta potential measurement, etc. Batch adsorption technique were carried out to understand the factors affecting fluoride adsorption, such as effects of initial pH, adsorbent dose, co-occurring ions, contact time, and temperature. The maximum adsorption capacity observed at pH between 5 and 7. The fluoride adsorption processes on CZ obeyed the pseudo-second-order rate equations and both Freundlich and DR isotherm models. The maximum adsorption capacity of 90.67 mg g⁻¹ was obtained. The thermodynamic parameters ΔH⁰ (positive), ΔS⁰ (positive), and ΔG⁰ (negative) indicating the fluoride sorption system was endothermic, spontaneous, and feasible. The CZ also successfully used as fluoride adsorbent for real field contaminated water collected from the Machatora district, Bankura, West Bengal, India. Graphical abstract Schematic representation of CZ synthesis and its application for lab as well as field water purification purpose.

The original publication of this paper contains a mistake.

Although Chinese government has implemented a series of laws, regulations, and policies to deal with air pollutants, air pollution is still one of the biggest concerns in China. Most of the cities in China suffered from extremely high air pollution levels and cannot meet the national air quality standards. In this study, we attempt to measure individuals’ average marginal willingness to pay (MWTP) in Beijing with the hedonic price model. We combine an extensive housing transaction dataset with emission data of six air pollutants from 2013 to 2016 in Beijing, China. When estimating the hedonic price function, we apply both ordinary least squares (OLS) and panel model with various fixed effects to better control for unobservables. The empirical results reveal that the concentrations of CO, NO₂, PM₂.₅, and PM₁₀ are significantly negatively correlated with housing prices. However, we found an insignificant relationship with the concentration of SO₂ and the concentration of O₃ appears to positively increase the housing values. Policy implications based on these results were also discussed.

The photodegradation and mineralization of the nitenpyrum [(E)-N-(6-chloro-3-pyridylmethyl)-N-ethyl-N′-methyl-2-nitrovinylidenediamine], which is one of the most popular neonicotinoid insecticides, were conducted in the presence of ZnO photocatalyst under solar irradiation. An initial nitenpyrum concentration of 10 ppm was completely degraded in the presence of ZnO after 30 min irradiation, while only 70% degradation was observed in the absence of ZnO. The effect of different parameters, for example, amount of ZnO, initial pH, light intensity, reaction temperature, and irradiation time, on the photocatalytic degradation of nitenpyrum was also evaluated. The drop of total organic carbon (TOC) as a consequence of mineralization of nitenpyrum was observed during the photocatalytic process. The kinetics of photocatalytic degradation followed a pseudo-first order law according to Langmuir-Hinshelwood model, and the rate constant is 0.140 min⁻¹. CO₂, chloride, and nitrate ions were observed as the end-products after completing degradation of nitenpyrum. The four kinds of intermediate products were identified by GC-MS during the decomposition of nitenpyrum. In order to investigate the degradation pathway of nitenpyrum, the point charge and frontier electron density at each atom on the molecule were determined using molecular orbital (MO) stimulation. The degradation mechanism was proposed, based on the identified intermediates. The solar photocatalytic degradation method can become an effective technique for the treatment of nitenpyrum-polluted water.

Metal accumulation by Spirulina platensis from synthetic effluents with the following chemical composition: Cr/Fe, Cr/Fe/Ni, Cr/Fe/Ni/Zn, and Cr/Fe/Ni/Zn/Cu during repeated cultivation cycle was investigated. Metal ions in different concentrations were added to the culture medium at the exponential and stationary phases of biomass growth and their uptake by biomass was traced using neutron activation analysis. The effect of metal ions on biomass and main biochemical components (proteins, carbohydrates, lipids, phycobilins, and β-carotene) was monitored. S. platensis keeps high metal accumulation capacity during 2–3 cultivation cycles, while the metal ions were added in the stationary phase of its growth. By adding metals in the exponential phase of growth in the following concentrations: 10 mg/L of chromium (VI), 5 mg/L of iron, 2 mg/L of zinc, nickel, and copper, Spirulina platensis acted as renewable accumulator only in Cr/Fe system. It maintained the accumulation capacity during three cultivation cycles when exposed to lower concentrations of metal ions. Its ability to accumulate metal ions during several cultivation cycles was ensured by the maintenance of the optimal level of proteins and lipid in biomass.