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The pervasive use of digital technologies in different scenarios has led to an increasing number of empirical studies on digital translanguaging. Following the emergence of the global pandemic and its huge impact on the education sector, attention to translanguaging among teachers and students in the digital context has reached a new height. This systematic review provides scholars with a current overview of research on digital translanguaging among teachers and students by analysing research backgrounds, the methodologies used, and the research themes of interest, supported by the software CiteSpace , to visualise the structure of existing research. A search of five databases identified 32 empirical studies on digital translanguaging among teachers and students, published from 2015 to 2022. The findings reveal that research on digital translanguaging for teachers and students is characterised by two distinct directions: one focused on teaching and learning, and the other on social purposes. More specifically, the former direction encompasses three subthemes: digital translanguaging pedagogy, the effects of digital translanguaging practices on English language writing, and translanguaging practices in digital multimodal composing. The implications of these findings for future research directions and pedagogical practice are discussed. [ABSTRACT FROM AUTHOR]

SnO 2 is recognized as an excellent electron transport layer. However, it does not possess the optimal morphology required by perovskite photovoltaic devices, and the conduction band of SnO 2 cannot match well with perovskite conduction bands. In the present study, we introduced graphene quantum dots (GQDs) into SnO 2. The results show that the introduction of graphene quantum dots effectively improved the morphology of the SnO 2 film, reduced the roughness of the surface, and increased the ohmic contact between the SnO 2 and perovskite layer. In addition, the conductivity of the SnO 2 film was improved, thereby facilitating the transfer of electrons. The optimized SnO 2 : GQDs layer reduced the density of defect state, suppressed the pinholes appearance to a certain extent, and facilitated the extraction of electrons, thereby ultimately improving the FF, and increasing the efficiency of the perovskite photovoltaic device. [ABSTRACT FROM AUTHOR]

• We developed a fully distributed water quality model for tile-drained catchments. • In-field management and catchment features control daily flows of water and NO 3 -N. • Subsurface flows, especially tile flow, dominate the water and NO 3 -N loads. • Roles of the model improvements in enhancing prediction accuracy were quantified. It is essential to identify the dominant flow paths, hot spots and hot periods of hydrological nitrate-nitrogen (NO 3 -N) losses for developing nitrogen loads reduction strategies in agricultural watersheds. Coupled biogeochemical transformations and hydrological connectivity regulate the spatiotemporal dynamics of water and NO 3 -N export along surface and subsurface flows. However, modeling performance is usually limited by the oversimplification of natural and human-managed processes and insufficient representation of spatiotemporally varied hydrological and biogeochemical cycles in agricultural watersheds. In this study, we improved a spatially distributed process-based hydro-ecological model (DLEM-catchment) and applied the model to four tile-drained catchments with mixed agricultural management and diverse landscape in Iowa, Midwestern US. The quantitative statistics show that the improved model well reproduced the daily and monthly water discharge, NO 3 -N concentration and loading measured from 2015 to 2019 in all four catchments. The model estimation shows that subsurface flow (tile flow + lateral flow) dominates the discharge (70–75%) and NO 3 -N loading (77–82%) over the years. However, the contributions of tile drainage and lateral flow vary remarkably among catchments due to different tile-drained area percentages and the presence of farmed potholes (former depressional wetlands that have been drained for agricultural production). Furthermore, we found that agricultural management (e.g. tillage and fertilizer management) and catchment characteristics (e.g. soil properties, farmed potholes, and tile drainage) play important roles in predicting the spatial distributions of NO 3 -N leaching and loading. The simulated results reveal that the model improvements in representing water retention capacity (snow processes, soil roughness, and farmed potholes) and tile drainage improved model performance in estimating discharge and NO 3 -N export at a daily time step, while improvement of agricultural management mainly impacts NO 3 -N export prediction. This study underlines the necessity of characterizing catchment properties, agricultural management practices, flow-specific NO 3 -N movement, and spatial heterogeneity of NO 3 -N fluxes for accurately simulating water quality dynamics and predicting the impacts of agricultural conservation nutrient reduction strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Heavy metal ions are common pollutants in the water environment, which have caused severe damage to the water environment, so it is necessary to monitor them. In this work, an electrochemical sensor based on aminated Zn (Ⅱ) metal-organic framework (ZIF-8-NH 2) enhanced by carbon nanotubes (CNTs) and bismuth (Bi) film was prepared for simultaneous detection of lead ions (Pb2+) and cadmium ions (Cd2+) in water samples. The ZIF-8-NH 2 /CNTs was prepared by electrostatic assembly with ultrasonic assistance. The results show that the combination of ZIF-8-NH 2 and CNTs not only can promote the three-dimensional distribution of CNTs, but also compensated for the poor electrical conductivity of ZIF-8-NH 2. Furthermore, the deposition of Bi film in situ promoted the enrichment of Pb2+ and Cd2+ in the detection process, further enhancing the electrochemical signal. Based on this, the prepared sensor displayed good linear ranges of 0.050–1.000 μM (Pb2+) and 0.100–0.700 μM (Cd2+), lower detection limits of 8.00 nM (Pb2+) and 12.0 nM (Cd2+) under optimal experiment condition. At last, this sensor was successfully applied to simultaneously detect Pb2+ and Cd2+ in paddy water and lake water with recovery rates of 97.88 ∼ 104.06% and relative standard deviation (RSD) lower than 6.24%. Most importantly, there is no significant difference between the developed electrochemical method and certified method (P < 0.05). This work provides a new idea for the simultaneous detection of heavy metal ions in the water environment. [Display omitted] • The support of ZIF-8-NH 2 realized the three-dimensional arrangement of CNTs. • The introduction of CNTs improved the poor conductivity of ZIF-8-NH 2. • Bismuth film prepared in situ further enhances the response signal. • The synergies of Bi, ZIF-8-NH 2 , and CNTs increase the detection performance. [ABSTRACT FROM AUTHOR]

Heavy metal ions are common industrial pollutants widely existing in the ecosystem, which can damage the environment and threaten human health. It is necessary to develop an accurate detection technology for the quantification of heavy metal ions in water environment. In this work, the electrochemical sensor based on bismuth/UiO-66-NH 2 @carbon nanohorns (Bi/UiO-66-NH 2 @CNHs) was developed for the simultaneous detection of lead ions (Pb2+) and cadmium ions (Cd2+). The results showed that the synergies of Bi/UiO-66-NH 2 @CNHs provided larger electrochemical active surface area and higher electron transfer ability than those of single materials. Furthermore, the high binding ability of bismuth film with heavy metal ions enhanced the enrichment of Pb2+ and Cd2+ during the electrochemical detection, thus further improving the response current. Based on this, the fabricated sensor displayed good linear relationships of 0.20 μM ∼ 0.80 μM of Pb2+ and Cd2+, with lower detection limits of 6.65 nM (Pb2+) and 10.56 nM (Cd2+). In the actual samples testing, the recovery rates of Pb2+ and Cd2+ were 97.10∼98.76% and 97.51∼103.32%, respectively, and the relative standard deviations of Pb2+ and Cd2+ were less than 4.10% and 4.02%, respectively. Moreover, there was no statistical significance difference between the developed sensor and the certified method. This work provides a new idea for the quantification of heavy metal ions in water environment. [Display omitted] • The synergies of Bi, UiO-66-NH 2 , and CNHs increase the electron transfer rate. • Bismuth further improves the ability to enrich heavy metal ions. • The method can detect Pb2+ and Cd2+ simultaneously. • The method proposed in this work has a low detection limit. [ABSTRACT FROM AUTHOR]

A wide variety of studies have revealed a substantial increase in nitrogen (N) deposition in China, but the lack of spatially-explicit time-series N deposition data set has long hindered us from assessing the impacts of atmospheric N input on ecosystem services. In this study, we combined site-level monitoring, gridded precipitation data and atmospheric transport modeling results to generate annual N bulk deposition data in China with a spatial resolution of 10 km × 10 km and a time span from 1961 to 2008. It shows that national average N deposition rate had large interannual variation, and it increased by 59%, from 12.64 kg N ha −1 yr −1 in the 1960s to 20.07 kg N ha −1 yr −1 in the recent decade, with the most rapid increase centered in the southeastern China that is already N-enriched. Large spatial variation as well as dry deposition input has to be taken into account when estimating the amount of N deposited onto land surface of China. The spatial and temporal information on N deposition derived from this study could be used by ecosystem, hydrological, and climate modeling as well as by policy makers for assessing the impacts of nitrogen enrichment on regional climate, water resources, and biogeochemical cycles. [ABSTRACT FROM AUTHOR]

Using a process-based Dynamic Land Ecosystem Model, we assessed carbon dynamics of urbanized/developed lands in the Southern United States during 1945–2007. The results indicated that approximately 1.72 (1.69–1.77) Pg (1P = 1015) carbon was stored in urban/developed lands, comparable to the storage of shrubland or cropland in the region. Urbanization resulted in a release of 0.21 Pg carbon to the atmosphere during 1945–2007. Pre-urbanization vegetation type and time since land conversion were two primary factors determining the extent of urbanization impacts on carbon dynamics. After a rapid decline of carbon storage during land conversion, an urban ecosystem gradually accumulates carbon and may compensate for the initial carbon loss in 70–100 years. The carbon sequestration rate of urban ecosystem diminishes with time, nearly disappearing in two centuries after land conversion. This study implied that it is important to take urbanization effect into account for assessing regional carbon balance. [Copyright &y& Elsevier]

Abstract: The effects of global change on ecosystem productivity and water resources in the southern United States (SUS), a traditionally ‘water-rich’ region and the ‘timber basket’ of the country, are not well quantified. We carried out several simulation experiments to quantify ecosystem net primary productivity (NPP), evapotranspiration (ET) and water use efficiency (WUE) (i.e., NPP/ET) in the SUS by employing an integrated process-based ecosystem model (Dynamic Land Ecosystem Model, DLEM). The results indicated that the average ET in the SUS was 710mm during 1895–2007. As a whole, the annual ET increased and decreased slightly during the first and second half of the study period, respectively. The mean regional total NPP was 1.18PgC/yr (525.2gC/m2/yr) during 1895–2007. NPP increased consistently from 1895 to 2007 with a rate of 2.5TgC/yr or 1.10gC/m2/yr, representing a 27% increase. The average WUE was about 0.71gC/kgH2O and increased about 25% from 1895 to 2007. The rather stable ET might explain the resulting increase in WUE. The average WUE of different biomes followed an order of: forest (0.93gC/kgH2O)>wetland (0.75gC/kgH2O)>grassland (0.58gC/kgH2O)>cropland (0.54gC/kgH2O)>shrubland (0.45gC/kgH2O). WUE of cropland increased the fastest (by 30%), followed by shrubland (17%) and grassland (9%), while WUE of forest and wetland changed little from the period of 1895–1950 to the period of 1951–2007. NPP, ET and WUE showed substantial inter-annual and spatial variability, which was induced by the non-uniform distribution patterns and change rates of environmental factors across the SUS. We concluded that an accurate projection of the regional impact of climate change on carbon and water resources must consider the spatial variability of ecosystem water use efficiency across biomes as well as the interactions among all stresses, especially land-use and land-cover change and climate. [Copyright &y& Elsevier]

[Display omitted] • A high-sensitivity and stable β-GICNT/rGO sensor was fabricated. • PEI was used to be an ideal modifier for the composite of rGO and c-CNTs. • PEI-CNTs and rGO form a three-dimensional stacking structure. • β-GICNT/rGO achieves highly sensitive detection of capsaicinoids. Rapid quantification of the content of capsaicinoids helps in classifying the degree of spiciness, standardized production, and quality control of leisure meat products. To rapidly quantify the content of capsaicinoids in soy sauce and pot-roast meat products, we developed an electrochemical sensor based on reduced graphene oxide (rGO)/polyethylene imine (PEI) - carbon nanotubes (CNTs)/β-cyclodextrin (β-CD) to detect the content of capsaicinoids in leisure meat products. Our findings showed that the electrochemical sensor presented highly sensitive performance toward capsaicinoids with a relatively wide linear range (0.01–100 µmol/L), a lower limit of detection (0.01 µmol/L), and an acceptable recovery rate (94.80–112.20%). The sensor performed well and was effective mainly because of the three-dimensional stacking structure and synergistic catalysis of rGO with cCNTs and also due to the improved dispersion of the composite material by β-CD. The sensor detected trace contents of capsaicinoids in leisure meat products, and thus, it might be considered for practical applications. [ABSTRACT FROM AUTHOR]

The introduction of nanostructures is an effective method to boost the photovoltaic performance of hybridized organic-inorganic halide perovskite-film solar cells. Taking into account their excellent light-scattering in the ultraviolet–visible range and their chemical inertness, silicon (Si) nanorods can be incorporated into the perovskite-film solar cells to enhance the light harvesting of the devices. By depositing Si nanorods between the prepared film and the substrate, the light scattering induced by the Si nanorods significantly promoted light absorption of the films. Moreover, resulting from the incorporation of Si nanorods, the enlarged grain size and compact structure of the films prolonged the lifetime of the carriers, which promoted the photoelectric properties of the perovskite films. By the appropriate incorporation of Si nanorods, the photovoltaic conversion efficiency of the CH 3 NH 3 Pb(Br 0.25 I 0.75) 3 -film-based solar cell was increased from 12.6% to 14.9% and the relative stability of the devices under dark humidity was improved. This strategy of employing low-cost and easily prepared Si nanorods to enhance the light harvesting of perovskite photovoltaic devices could be applied to photovoltaic devices based on perovskite films with other compositions. [ABSTRACT FROM AUTHOR]

A wide range of estimates on global wetland methane (CH 4 ) fluxes has been reported during the recent two decades. This gives rise to urgent needs to clarify and identify the uncertainty sources, and conclude a reconciled estimate for global CH 4 fluxes from wetlands. Most estimates by using bottom-up approach rely on wetland data sets, but these data sets show largely inconsistent in terms of both wetland extent and spatiotemporal distribution. A quantitative assessment of uncertainties associated with these discrepancies among wetland data sets has not been well investigated yet. By comparing the five widely used global wetland data sets (GISS, GLWD, Kaplan, GIEMS and SWAMPS-GLWD), it this study, we found large differences in the wetland extent, ranging from 5.3 to 10.2 million km 2 , as well as their spatial and temporal distributions among the five data sets. These discrepancies in wetland data sets resulted in large bias in model-estimated global wetland CH 4 emissions as simulated by using the Dynamic Land Ecosystem Model (DLEM). The model simulations indicated that the mean global wetland CH 4 emissions during 2000–2007 were 177.2 ± 49.7 Tg CH 4 yr −1 , based on the five different data sets. The tropical regions contributed the largest portion of estimated CH 4 emissions from global wetlands, but also had the largest discrepancy. Among six continents, the largest uncertainty was found in South America. Thus, the improved estimates of wetland extent and CH 4 emissions in the tropical regions and South America would be a critical step toward an accurate estimate of global CH 4 emissions. This uncertainty analysis also reveals an important need for our scientific community to generate a global scale wetland data set with higher spatial resolution and shorter time interval, by integrating multiple sources of field and satellite data with modeling approaches, for cross-scale extrapolation. [ABSTRACT FROM AUTHOR]

It is highly uncertain on how human and natural environmental factors have altered methane (CH 4 ) emissions from terrestrial ecosystems in India. Using a process-based, Dynamic Land Ecosystem Model (DLEM) driven by climate, land cover and land use change (LCLUC), atmospheric nitrogen deposition (NDEP), atmospheric carbon dioxide (CO 2 ) concentration, and tropospheric ozone (O 3 ) pollution, we examined CH 4 flux from terrestrial in India during 1901–2010. The DLEM simulations have shown that total CH 4 flux over the country ranged from 2.9 Tg C year −1 to 6.5 Tg C year −1 with significant inter-annual variations driven by climate during 1901–2010. Contemporary CH 4 emissions have primarily occurred from rice fields (3.9 ± 0.9 Tg C year −1 ) while wetlands contributed to 2.1 ± 0.6 Tg C year −1 in the 2000s. During 1901–2010, total CH 4 emission from the terrestrial biosphere has increased by ∼2.1 Tg C year −1 . LCLUC has increased CH 4 emissions by 2.3 Tg C year −1 primarily due to increase in the rice-based cropping systems as well as irrigation expansion during the study period. Elevated CO 2 concentration stimulated plant biomass production in both rice fields and wetlands that increased CH 4 emissions by 0.7 Tg C year −1 . On the contrary, climate change decreased net CH 4 emissions by ∼1.2 Tg C year −1 due to negative effects of extreme high temperature as well as occurrences of extreme drought events on plant growth. Our study suggests that LCLUC and elevated CO 2 concentration have significantly increased CH 4 emissions from terrestrial ecosystems in India. [ABSTRACT FROM AUTHOR]

Abstract: Natural wetland ecosystem plays an important role in global climate change due to its large amounts of stored carbon and nitrogen. The Sanjiang Plain, Northeast China, encompasses large area of natural freshwater marshy wetlands. However, the magnitude and temporal patterns of major greenhouse gases (GHGs: CO2, CH4 and N2O) in this region remain far from certain. Here we used a process-based ecosystem model to examine GHGs fluxes and their underlying mechanisms in the marshland across the Sanjiang Plain over the period 1949–2008. Simulation results indicated that during the past 60 years, the Sanjiang Plain''s marshland acted as a net CO2 sink of 4.20 ± 0.44 Tg C yr−1, while approximately 0.46 ± 0.02 Tg C yr−1 for CH4 and 0.02 ± 0.00 Tg N yr−1 for N2O were released to the atmosphere. Land cover and land use change (LCLUC) was the primary driver for GHGs changes. Climate change and tropospheric ozone (O3) pollution decreased CO2 uptakes, yet elevated CO2 concentration and nitrogen deposition increased CO2 uptake. Tropospheric O3 pollution and nitrogen deposition decreased CH4 emission by 7.94 Gg C and 0.41 Gg C, respectively, while elevated CO2 concentration increased the CH4 emission by 133.81 Gg C. Accumulatively, tropospheric O3 pollution and climate change contributed approximately 5.37% and 4.89% to the increased N2O emission, respectively, while elevated CO2 concentration reduced 2.81% of the N2O emission. The global warming potential (GWP) ranged from −1.81 Tg CO2eq yr−1 in the 1970s to 29.15 Tg CO2eq yr−1 in the 2000s. The decadal GWP by CO2 fluxes shifted from negative values between the 1950s and the 1990s to positive values in the 2000s, while CH4 and N2O emissions enhanced GWP from the 1950s to the 2000s. The total GWP decreased from the 1950s to the 1970s, but increased from the 1980s to the 2000s. This suggested that the reduced GWP by decreased CH4 emissions was gradually offset by the increased GWP by increased N2O emissions and decreased CO2 sink from the 1980s to the 2000s, implying that a full accounting of the greenhouse gas balance is essential in assessing global change impacts. [Copyright &y& Elsevier]

The fabrication process for perovskite films is critical for their microstructure and photo-electrical properties. In this study, a pre-preparation step for perovskite crystal particles with a conventional two step spin-coating method was introduced for improving the quality of the prepared perovskite films. By adding CH 3 NH 3 I into the PbI 2 precursor solution and performing anti-solvent extraction during the preparation process, a small amount of perovskite crystal particles was produced in the PbI 2 layers. We demonstrated that the pre-preparation of perovskite crystal particles enhanced the grain size and coverage of the perovskite films due to modification of the surface morphology and crystallisation of the PbI 2 layers. Furthermore, after optimisation, the crystal size in the perovskite films reached almost 3 μm, which tremendously enhanced the generation and transportation of photo-generated carriers in photo-voltaic devices. Under illumination, the fill factor (FF) and short circuit current density (J sc) of the corresponding devices increased, and the photoelectric conversion efficiency (PCE) was enhanced from 11.7% to 17.5%. Further, the stability of the devices in dark humid air was improved. Our results demonstrate that pre-preparing the perovskite crystal particles is useful for the fabrication of high-quality perovskite films. This approach can also be applied to devices based on perovskite films with other compositions. • Sequential deposition method has been improved for the preparation of perovskite films. • The high quality perovskite films were prepared by the pre-crystallisation. • The crystal size in the perovskite films reached almost 3 μm. • The PCE of perovskite solar cells have been greatly improved. [ABSTRACT FROM AUTHOR]