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Physical, chemical, and biological techniques can be used to manage eutrophication, a global environmental hazard that might worsen. Biomanipulation is an eco-friendly, cost-effective, and potentially profitable technology for ecological restoration. This review contrasts nonclassical biomanipulation, which uses planktivorous fish to reduce algal blooms, with classical biomanipulation, which employs piscivorous fish to indirectly increase zooplankton populations to manage eutrophication. Owing to certain challenges associated with classical biomanipulation, including the elimination of planktivorous fish, the increase in the number of macrophytes, and the decrease in phosphorus (internal as well as external), preference is given to nonclassical biomanipulation. In tropical lakes with high productivity, where reducing the concentration of nutrients is nearly impossible, nonclassical biomanipulation can also be utilized to control algal blooms. In both lakes and confined water bodies, nonclassical biomanipulation altered the phytoplankton composition at the beginning of the experiment. Using nonclassical biomanipulation, 63% of the 30 studies we reviewed revealed that phytoplankton were successfully controlled. In Lakes Donghu and Qiandaohu, two planktivorous fish, Hypophthalmichthys molitrix and Hypophthalmichthys nobilis nobilis, effectively suppressed Microcystis blooms. However, H. molitrix and H. nobilis are useful for controlling eutrophic environments that do not contain enough macrozooplankton. When large herbivorous zooplankton are unable to effectively suppress nuisance algal blooms, nonclassical biomanipulation has been proven to be an effective strategy; however, it is useless when nanophytoplankton species are blooming organisms. Furthermore, experiments are needed to fully understand the effectiveness of this technique, as environmental parameters such as region and season strongly impact the behavior of water bodies.

Abstract The pursuit of designing superconductors with high Tc has been a long‐standing endeavor. However, the widespread incorporation of doping in high Tc superconductors significantly impacts electronic structure, intricately influencing Tc. The complex interplay between the structural composition and material performance presents a formidable challenge in superconductor design. Based on a novel generative model, diffusion model, and doping adaptive representation: three‐channel matrix, we have designed a high Tc superconductors inverse design model called Supercon‐Diffusion. It has achieved remarkable success in accurately generating chemical formulas for doped high Tc superconductors. Supercon‐Diffusion is capable of generating superconductors that exhibit high Tc and excels at identifying the optimal doping ratios that yield the peak Tc. The doping effectiveness (55%) and electrical neutrality (55%) of the generated doped superconductors exceed those of traditional GAN models by more than tenfold. Density of state calculations on the structures further confirm the validity of the generated superconductors. Additionally, we have proposed 200 potential high Tc superconductors that have not been documented yet. This groundbreaking contribution effectively reduces the search space for high Tc superconductors. Moreover, it successfully establishes a bridge between the interrelated aspects of composition, structure, and property in superconductors, providing a novel solution for designing other doped materials.

Tidal creeks play a crucial role in lateral transport of carbon and nutrients from tidal salt marshes. However, the specific impact of tidal creek development on carbon and nutrient distribution within the marsh remains poorly understood. The objective of this study is to assess the influence of lateral tidal flooding through the tidal creeks on the spatial distribution of carbon and nitrogen fractions in the soils of a Chinese temperate salt marsh. We conducted a comprehensive analysis of the relative variations in different carbon and nitrogen fractions, along with soil physicochemical and microbial indicators, between the bank soil of the tidal creek and its lateral inland soils across high, middle, and low flats. Our findings highlight that tidal creek development significantly affects the middle flat, leading to substantial variations in organic carbon and total nitrogen. The low flat mainly experiences changes in dissolved inorganic carbon levels. Furthermore, a lateral increase in microbial biomass is observed in the middle flat, indicating that the significantly lower SOC in the middle flat might be ascribed to enhanced microbial decomposition. The lateral enrichment of dissolved inorganic carbon in the low flat is possibly related to the nearshore location and/or abiotic adsorption in inorganic carbon sequestration. Overall, this study demonstrates the critical role of tidal creek development in shaping the distribution patterns of carbon and nitrogen fractions in tidal salt marshes.

In arid agriculture, the effective allocation of scarce water resources and the assessment of irrigation shortage risks are critical water management practices. However, these practices are faced with inherent and unignorable uncertainties affecting multiple variables. This study aims to model the typical uncertainties in these practices and understand how they impact the allocation of scarce water resources. We advocate for a nuanced consideration of variable characteristics and data availability, variation, and distribution when choosing uncertainty representation methods. We proposed a comprehensive framework that integrates the cloud model to delineate scenarios marked by subjective vagueness, such as “high” or “low” prices. Simultaneously, the stochastic method was used for modeling meteorological and hydrological variables, notably precipitation and crop evapotranspiration. Additionally, to navigate subjectivity and imprecise judgment in standards classification, this framework contains a cloud-model-based assessment method tailored for evaluating irrigation shortage risks. The proposed framework was applied to a real-world agricultural water management problem in Liangzhou County, northwest China. The results underscored the efficacy of the cloud model in representing subjective vagueness, both in the optimization process and the subsequent assessment. Notably, our findings revealed that price predominantly influences net benefits, and that precipitation and crop evapotranspiration emerge as decisive factors in determining optimal irrigation schemes. Moreover, the identification of high water storage risks for maize in the Yongchang and Jinyang districts serves as a reminder for local water managers of the need to prioritize these areas. By adeptly modeling multiple uncertainties, our framework equips water managers with tools to discern sensitive variables. We suggest that enhanced precipitation and evapotranspiration forecasts could be a promising way to narrow the uncertainties.

The invasion of Spartina alterniflora has threatened and damaged coastal wetlands in China, therefore, control and removal of this severe invasive plant are urgently needed. Green chemical control is an effective and low-cost method that can be used for large-scale removal of invasive specie. To study the control effect of imazapyr on S. alterniflora and evaluate its impact on other species and the wetland environment, a control experiment was set up in the Yellow River Delta Reserve in Shandong Province in May 2021. A total of 9 treatments were set up in the experiment: 25 % (W) imazapyr water (main agent), three treatments with dose gradients of 3.0, 6.0, and 9.0 L/acre, and the main agent at a dose of 6.0 L/acre with six treatments of AGE 809 (adjuvant A) and AGE 852 (adjuvant B) with dose gradients of 1.3, 2.6, and 5.2 L/acre, respectively. The results showed that after 60 days of application, the control efficiency of Spartina alterniflora was over 90 %, and the residual amount was small in the plots with the main agent additive

Smooth cordgrass (Spartina alterniflora) introduced to China in 1970 s for coastline stabilization threatening the habitat range of native Phragmites australis and even become more adaptive than P. australis. Thus, we used electronic universal testing machine and Van Soest method to compare the morphological and biomechanical responses of these two species to wave interference in the Yellow River Delta, east China. Our study showed that the morphological response of P. australis was more sensitive to waves with shorter individuals in wave zones but larger stem diameter and higher biomass than those in none-wave zones, while S. alterniflora did not exhibit such variations. In wave zones, S. alterniflora invaded P. australis’ habitat regardless higher stem-bending resistance of P. australis with excessive energy allocated in stem growth while decreasing reproduction and fitness. Compared with the none-wave zones, S. alterniflora allocated excessive energy in the stem to resist wind interference, and they are less fitted than P. australis. Thus, economic energy allocation to wave mechanical interference contributed to the successful invasion of S. alterniflora to landward in estuaries. S. alterniflora continued to expand landward in a semi-saline area but the community pattern may maintain the status quo for areas with low salinity and high wave interference.

Staphylococcus aureus is a common pathogen that causes various infections. Therefore, it is crucial to develop a fast and easy detection method for diagnosing and preventing S. aureus infections. In this study, MIRA assay was developed and validated (specificity; 100%) for the detection of S. aureus with nuc as the target gene. The reaction temperature and reaction time were then optimized, and the best reaction was at 40°C, 20 min. The assay could detect S. aureus in only 25 min. Additionally, the limit of detection of MIRA was 5 × 102 CFU/ml, 10-fold lower than that of the traditional PCR. Furthermore, this assay efficiently detected 219 S. aureus of 335 strains obtained from different bacterial samples (detection accuracy; 99.40%). In conclusion, this study provides a rapid and easy-to-operate method for the detection of S. aureus, and thus can be used for the timely diagnosis and prevention of S. aureus infection.

The leaf surfaces of plants are important organs for retaining particulate matter (PM). They can be renewed via washout processes (e.g., rainfall), thereby restoring the ability to retain new PM. Most of the current studies have focused on the mechanisms of rainfall characteristics on the renewal of PM on plant leaf surfaces and interspecific differences, while the effects of different leaf heights on PM renewal within the same plant canopy have been less studied. In addition, the dynamics of PM during rainfall, especially the water-soluble ions (WSII) component, are often neglected. This research used Salix matsudana, a tree species with a significant natural height difference between the upper and lower leaves of its canopy, as its study object. Using artificially simulated rainfall, the rainfall intensity was quantified as low, medium, and high (i.e., 30 mm/h, 45 mm/h, and 60 mm/h), and the rainfall process was divided into three sub-stages: pre (0–20 min), mid (20–40 min), and post (40–60 min). The experimental setup was divided into upper (2 m) and lower leaves (1 m) according to the height of the canopy. The concentration and distribution of water-insoluble PM (WIPM) were obtained using the elution weighing method, whereas WSII were obtained using ion chromatography. The dynamics of WIPM and WSII during the removal of PM from the leaf surface by rainfall were studied at different canopy heights, and the results showed that the composition and proportions of WIPM and WSII varied at different stages of the rainfall process and that the concentrations of WIPM and WSII removed from the upper leaves differed slightly from those of the lower leaves. In particular, the concentrations of WIPM and WSII removed from the lower leaves were greater than those from the upper leaves at high rainfall intensity (60 mm/h), showing consistency between rainfall removal of PM from the leaf surface at different heights within the plant canopy and deposition of PM, while at low (30 mm/h) and medium (45 mm/h) rainfall intensities the performance was slightly different.

Considering the safety of ammunition, safety and arming (S&A) devices are usually designed in pyrotechnics to control energy transfer through a movable barrier mechanism. To achieve both intelligence and miniaturization, electrothermal actuators are used in MEMS S&A devices, which can drive the barrier to an arming position actively. However, only when the actuators’ energy input is continuous can the barrier be stably kept in the arming position to wait for ignition. Here, we propose the design and characterization of a double-layer electrothermal MEMS S&A Device with a bistable mechanism. The S&A device has a double-layer structure and four groups of bistable mechanisms. Each bistable mechanism consists of two V-shape electrothermal actuators to drive a semi-circular barrier and a pawl, respectively, and control their engagement according to a specific operation sequence. Then, the barrier can be kept in the safety or the arming position without energy input. To improve the device’s reliability, the four groups of bistable mechanisms are axisymmetrically placed in two layers to constitute a double-layer barrier structure. The test results show that the S&A device can use constant-voltage driving or the capacitor–discharge driving to drive the double-layer barrier to the safety or the arming position and keep it on the position passively by the bistable mechanism.

The main factors controlling plant litter decomposition rates are litter quality and environmental factors. We investigated how different salinity and inundation conditions influence the decomposition rate and how litter quality affects dynamic change during the decomposition process in the Yellow River Delta wetland in northeastern China. To do this, we designed a field experiment using the litter bag method to study two selected dominant halophyte species (Phragmites australis and Suaeda salsa). We found litter decomposed faster when inundated across a range of salinities. Both the water chemical oxygen demand and NH3-N concentration were inversely correlated with salinity. The ratio of nitrogen to phosphorous showed an upward trend during the process of decomposition. The decomposition rate increased during the later stage of the process. Under inundation conditions, the decomposition rate of only S. salsa showed a positive correlation with salinity. The study results suggest that moderately higher salinity would increase anaerobic decomposition owing to the combined effect of salinity and inundation. The implications of our findings may be used to further assess the impact of environmental parameters and litter quality on the decomposition rate in estuarine wetland and can help determine a strategy for wetland reparation and remediation.

To increase our knowledge of PM2.5 concentrations near the surface in a forest park in Beijing, an observational study measured the concentration and composition of PM2.5 in Beijing Olympic Forest Park from 2014 to 2015. This study analyzed the meteorological factors and removal efficiency at 1.5 m above the ground (human breathing height) over the day in the forest. The results showed that the average concentrations of PM2.5 near the surface peaked at 07:00–09:30 and reached their lowest at 12:00–15:00. Besides, the results showed that the annual concentration of PM2.5 in the forest was highest during winter, followed by spring and fall, and was lowest during summer. The main chemical components of PM2.5 near the surface in the forest were SO42− and NO3−, which accounted for 68.72% of all water-soluble ions that we observed. The concentration of PM2.5 in the forest had a significant positive correlation with relative humidity and a significant negative correlation with temperature. The removal efficiency near the surface showed no significant variation through the day or year. In the forest, the highest removal efficiency occurred between 07:00 and 09:30 in summer, while the lowest occurred between 09:30 and 12:00 in winter.

With the rapid development of industry, studies on lead pollution in total suspended particulate matter (TSP) have received extensive attention. This paper analyzed the concentration and pollution sources of lead in the Cuihu Wetland in Beijing during the period of 2016–2017. The results show that the lead contents in TSP in the Cuihu Wetland were approximately equal in summer and spring, greater in winter, and greatest in autumn. The corresponding lead concentrations were 0.052, 0.053, 0.101, and 0.115 ng/m3, respectively. We compared the 206Pb/207Pb data with other materials to further understand the potential sources of atmospheric lead. The mean values of 206Pb/207Pb from spring to winter were 1.082, 1.098, 1.092, and 1.078, respectively. We found that the lead sources may be associated with coal burning, brake and tire wear, and vehicle exhaust emissions. We also calculated the enrichment factor values for the four seasons, and the values were all much greater than 10, indicating that the lead pollution is closely related to human activities.

Urban forests have been shown to be efficient for reducing air pollutants especially for particulate matters (PMs). This study aims to reveal the PM blocking capacity of two common artificial landscape species, Sabina chinensis and Liriodendron chinense and to investigate spatial-temporal heterogeneities by estimating the vegetation collection velocity of coarse (PM10) and fine particles (PM2.5) during different seasons and heights. PM concentration and meteorological data were collected on both leeward and windward sides of trees during the daytime in both summers and winters from 2013 to 2015. Concentration and meteorological monitors were installed at three heights, bottom (1.5 m), middle (3.5 m), and top (5.5 m) of the canopy. The results showed: During daytime, the collection velocity changed and PM2.5 collection velocity was much higher than that of PM10. Furthermore, the maximum collection velocities of L. chinense and S. chinensis occurred at 14:00-16:00 both in summer and winter. Moreover, the collection velocity had a positive correlation with wind speed and temperature. The blocking capacities of L. chinense and S. chinensis varied from season to season, and the concentrations of particulate matter indicate the middle canopy of both species as the most effective part for TSP blocking. Furthermore, these two species are more effective blocking in PM2.5 than PM10. The blocking capacity of S. chinensis is generally better. The vegetation collection is the major process of PM removal near the ground and sedimentation was not taken into consideration near the ground.

Atmospheric particulate matter (PM) deposition which involves both dry and wet processes is an important means of controlling air pollution. To investigate the characteristics of dry and wet deposition in wetlands, PM concentrations and meteorological conditions were monitored during summer at heights of 1.5 m, 6 m and 10 m above ground level at Cuihu Wetland (Beijing, China) in order to assess the efficiency of PM2.5 (particles with an aerodynamic size of 6 m (0.007 ± 0.003 μg·m-2·s-1) > 1.5 m (0.005 ± 0.002 μg·m-2·s-1). And the following deposition fluxes for PM10 were recorded: 10 m (2.163 ± 2.941 μg·m-2·s-1) > 1.5 m (1.565 ± 0.872 μg·m-2·s-1) > 6 m (0.987 ± 0.595 μg·m-2·s-1). In the case of wet deposition, the relative deposition fluxes for PM2.5 and PM10 were 1.5 m > 10 m > 6 m, i.e. there was very little difference between the fluxes for PM2.5 (0.688 ± 0.069 μg·m-2·s-1) and for PM10 (0.904 ± 0.103 μg·m-2·s-1). It was also noted that rainfall intensity and PM diameter influenced wet deposition efficiency. Dry deposition (63%) was more tilted towards removing PM10 than was the case for wet deposition (37%). In terms of PM2.5 removal, wet deposition (92%) was found to be more efficient.

In recent years, the rapid development of industrialization and urbanization has caused serious environmental pollution, especially particulate pollution. As the "Earth's kidneys," wetland plays a significant role in improving the environmental quality and adjusting the climate. To study how wetlands work in this aspect, from the early autumn of 2014 to 2015, we implemented a study to measure the PM concentration and chemical composition at three heights (1.5, 6, and 10 m) during different periods (dry, normal water, and wet periods) in the Cuihu wetland park in Beijing for analyzing the dry deposition flux and the effect of meteorological factors on the concentration. Results indicated that (1) the diurnal variations of the PM2.5 and PM10 concentrations at the three heights were similar in that the highest concentration occurred at night and the lowest occurred at noon, and the daytime concentration was lower than that at night; (2) the PM2.5 and PM10 concentrations also varied between different periods that wet period > normal water period > wet period, and the concentration at different heights during different periods varied. In general, the lowest concentration occurred at 10 m during the dry and normal water periods, and the highest concentration occurred at 1.5 m during the wet period. (3) SO42-, NO3-, and Cl- are the dominant constituents of PM2.5, accounting for 42.22, 12.6, and 21.56%, respectively; (4) the dry depositions of PM2.5 and PM10 at 10 m were higher than those at 6 m, and the deposition during the dry period was higher than those during the wet and normal water periods. In addition, the deposition during the night-time was higher than that during the daytime. Moreover, meteorological factors affected the deposition, the temperature and wind speed being negatively correlated with the deposition flux and the humidity being positively correlated. (5) The PM10 and PM2.5 concentrations were influenced by meteorological factors. The PM2.5 and PM10 concentrations were negatively correlated with temperature and wind speed but positively correlated with relative humidity.

In bulk heterojunction photovoltaic systems both the open-circuit voltage as well as the short-circuit current, and hence the power conversion efficiency, are dependent on the optical bandgap of the electron-donor material. While first-principles methods are computationally intensive, simpler model Hamiltonian approaches typically suffer from one or more flaws: inability to optimize the geometries for their own input; absence of general, transferable parameters; and poor performance for non-planar systems. We introduce a set of new and revised parameters for the adapted Su-Schrieffer-Heeger (aSSH) Hamiltonian, which is capable of optimizing geometries, along with rules for applying them to any [Formula: see text]-conjugated system containing C, N, O, or S, including non-planar systems. The predicted optical bandgaps show excellent agreement to UV-vis spectroscopy data points from literature, with a coefficient of determination [Formula: see text], a mean error of -0.05 eV, and a mean absolute deviation of 0.16 eV. We use the model to gain insights from PEDOT, fused thiophene polymers, poly-isothianaphthene, copolymers, and pentacene as sources of design rules in the search for low bandgap materials. Using the model as an in-silico design tool, a copolymer of benzodithiophenes along with a small-molecule derivative of pentacene are proposed as optimal donor materials for organic photovoltaics.