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Pure sulfide-based Cu 2 ZnSnS 4 (CZTS) stands as a competitive photovoltaic material, composted of earth-abundant, low-cost, and stable constituent elements. The stacked electrodeposition process has garnered attention owing to its facile regulation of elemental composition, and its non-vacuum, room-temperature, water-based solvent operating conditions. However, the limitation based on the stacked electrodeposition-processed CZTS primarily stems from the numerous defects and detrimental interfaces induced by the deficient intermetallic diffusion. Herein, a Se nanoparticle layer at the back interface is introduced to enhance the intermetallic diffusion, optimize the precursor morphology, and subsequently accelerate the grain growth. Comprehensive characterizations reveal Se, acting as the hetero-nucleation seeds, catalyzes Cu deposition and promotes a highly porous structure with a homogeneous elemental distribution. Consequently, high-quality CZTS with enhanced crystallinity and passivated defects is achieved, thereby promoting carrier transport and suppressing non-radiative recombination. These sequential positive effects result in a substantial improvement in short current density (J sc) and fill factor (FF), attaining an improved efficiency. Our findings offer a promising strategy to overcome the issues of the stacked electrodeposition-processed films and highly contribute to the development of high-quality CZTS-based solar cells. [Display omitted] • A novel strategy is proposed to address the issue of stacked electrodeposited CZTS solar cells. • Se-nanoparticles layer at CZTS/Mo interface is introduced to reinforce the intermetallic diffusion. • Se-nanoparticles layer acts as hetero-nucleation seeds to mediate the Cu deposition and optimize the precursor morphology. • The grain growth is accelerated and defects are inhibited, leading to an improved CZTS efficiency. [ABSTRACT FROM AUTHOR]

• B-MMI and three indices are built to assess benthic macroinvertebrate integrity. • The shared effects of hydromorphology and physico-chemistry are analyzed. • The main environmental factors contributed to B-MMI, D/A, S/T and FFGs for substrate types are recognized. Hydrology, water quality and biological pressures can influence structure and function of stream and river ecosystems. However, in practice, identifying the shared effects of factors on communities instead of isolated effects is a challenging task. Benthic macroinvertebrate community can reflect bottom conditions of streams and is less disturbed by river flows and human activities. Therefore, it is suitable to analyze the shared effects of hydromorphological and physico-chemical parameters. Benthic macroinvertebrate based Multi-Metric Index (B-MMI) was built to evaluate overall status and the effects on three biological traits were calculated, including diversity and abundance (D/A), sensitivity and tolerance to pollutions (S/T) and functional feeding groups (FFGs). Redundancy Analysis (RDA) was performed to evaluate the percentage of explained variance of 18 hydromorphological and physico-chemical parameters on invertebrate community. Our analysis showed that the two facets of the environment have high shared explained variances (28.2%–44.5%). Relatively, physico-chemical parameters have higher contributions on B-MMI than hydromorphological parameters. Seasonal analysis showed the shared effects are higher in dry season than wet season. S/T characteristics are most sensitive to seasonal shared effects, which in wet season can best show the isolated effects of the two facets of the environment. At the catchment-scale, middle stretches had higher B-MMI values since stony substrate and less disturbed land use types. And reach studies showed channel morphology contributed more in stony reaches while bottom conditions contributed more in silty and sandy reaches. Our findings consequently give rise to concern to the integrity index of benthic invertebrate community, which allows to show large shared effects of hydromorphological and physico-chemical factors. Besides catchment scale, reach scale also help add the perspective of substrate diversity and heterogeneity in habitat restoration and conservation. [ABSTRACT FROM AUTHOR]

The rapid development of digital economy challenges the innovation theory under the traditional economic background. The consequences of digital economy on breakthrough innovations remain unknown, especially in emerging markets. Using patent data of 1728 listed companies in China from 2010 to 2020, we study the impact of digital economy on firms' breakthrough innovations. The results show that digital economy can significantly promote breakthrough innovations in Chinese firms in the short and long term. In contrast to existing research documenting a tension between breakthrough and incremental innovations, we find that the promoting effect on breakthrough innovations does not come at the expense of incremental innovations. Further analysis reveals that digital economy provides resources and motivations for firms to develop breakthrough innovations by easing financing constraints, promoting talent aggregation, and increasing uncertainty in the competitive landscape. Additionally, digital economy can promote breakthrough innovations in non-state-owned, growing and aging firms more than in state-owned and mature firms; and its positive impact is more significant in high-tech firms than in non-high-tech firms. • The digital economy can promote firms to develop breakthrough innovations. • The digital economy promotes breakthrough innovation not at the expense of incremental innovation. • The mediating mechanisms are easing financing constraints, promoting talent pools and increasing environmental uncertainty. • The impact of the digital economy on breakthrough innovation is heterogeneous across firms, industries, and life cycles. [ABSTRACT FROM AUTHOR]

The composition, abundance and age structure of groundwater-dependent vegetation (GDV) are tightly coupled with groundwater level variation. Modeling the space–time dynamics of GDV is valuable for ecosystem conservation and recovery. But there are few modeling frameworks on GDV space–time dynamics. In this study, we propose a stochastic process-based theoretical framework, and develop a Species-specific Theoretical Evolution Model (STEM) to analyze and simulate GDV dynamics. In the model, the groundwater level variation is described as stochastic processes. Based on this method, the temporal dimension of vegetation dynamics is involved. The model focuses on the life cycle of same-aged population and divides this life cycle into two evolution phases. Each phase is formulated with a stochastic differential equation respectively. The solution processes interpret the probability distributions of GDV, and the plot-wised model application in a certain geomorphology area derives different typical distribution patterns for the population abundance and lifespan. The results also reveal the positive effects of water regulations on vegetation restoration. This framework describes the spatial–temporal dynamics of GDV rather than providing a stationary solution. It can adapt to the non-stationarity of groundwater level variations and distinctive sensitivity during the plants life cycle because of the Markov property of stochastic equations. The model can also help to predict vegetation responses under the groundwater level variations. [ABSTRACT FROM AUTHOR]

AQUATOX, coupled water quality and estuarine hydrodynamic model based on food web, was implemented to simulate the temporal variations of gross primary production (GPP) and ecosystem respiration (R e ) in Haihe estuary of North China, also, the parameter sensitivity was calculated and the main factors of GPP and R e were analyzed. Results showed that GPP ranged from 16 to 1789 mg O 2  m −2  d −1 and R e from 56 to 1083 mg O 2  m −2  d −1 , respectively. GPP and R e exhibited significant temporal variation and both reached the highest level in June, however, GPP and R e reduced in July and August, which could be explained by the increase of turbidity caused by high freshwater inflow discharge in rainy season. Maximum photosynthetic rate of blue-greens was the most sensitive parameter to GPP. Re was strongly related to temperature, the most sensitive parameter was average epilimnetic temperature. A significant negative correlation was found between GPP, R e and freshwater inflow. Furthermore, significant direct and indirect effects of tidal height on GPP were observed by path analysis, increased turbidity induced by tidal action might explain the influence on GPP. [ABSTRACT FROM AUTHOR]

Considering relationships between environmental factors and aquatic ecosystems, obtaining a clear understanding of river habitat integrity plays a key role in addressing habitats’ disturbances. Since benthic macroinvertebrate assembly can reflect the benthic stream conditions, we assessed the river habitat integrity based on benthic macroinvertebrate multi-metric model. The development and application of Benthic macroinvertebrate multi-metric index (B-MMI) was based on samples collected from October to November 2014 at representative sites from upper to lower reaches in Luanhe River, Haihe River Basin, China. Hydromorphology, water quality and land use patterns were considered to define reference sites and metrics related to macroinvertebrate community composition, structure, function and tolerance to pollution were selected as candidate metrics. Then, Range, sensitivity and redundancy tests were used to select candidate metrics based on their ability to distinguish the reference and impaired sites. As the result, four core indicators were selected to build the B-MMI: EPT%, Tubificidae%, BI (Biotic Index), Collect-Gatherers%. The values of B-MMI ranged from 0.21 to 3.75 in 17 sites. Based on B-MMI values, the habitat integrity of 29% sites were in very poor status and 6% were in excellent status. The upper reaches were influenced by animal husbandry and tourism, while the lower reaches were influenced by urbanization and dams. More good habitats were located in middle reaches under less human disturbances. Overall, this B-MMI shows promise for developing biomonitoring tools to assess the habitat integrity of streams, to provide appropriate restoration strategies and policies. [ABSTRACT FROM AUTHOR]

The distribution, seasonal variations and ecological risk assessment of polycyclic aromatic hydrocarbons (PAHs) in water from three estuaries in Hai River Basin of China, which has been suffering from different anthropogenic pressures, were investigated. In three estuaries, the average concentration of ΣPAHs was the lowest in Luan River estuary, followed by Hai River estuary, and the highest in Zhangweixin River estuary. There were significant seasonal variations in ΣPAHs, the concentrations of ΣPAHs were higher in November than in May and August. The composition profiles of PAHs in different sites were significantly different, and illustrated seasonal variations. Generally, 2-ring (Nap) and 3-ring PAHs (Acp, Fl and Phe) were the most abundant components at most sampling sites in three estuaries. The PAHs in three estuaries were mainly originated from pyrogenic sources. A method based on toxic equivalency factors (TEFs) and risk quotient (RQ) was proposed to assess the ecological risk of ΣPAHs, with the ecological risk of individual PAHs being considered separately. The results showed that the ecological risks caused by ΣPAHs were high in Hai River estuary and Zhangweixin River estuary, and moderate in Luan River estuary. The mean values of ecological risk in August were lower than those in November. The contributions of individual PAHs to ecological risk were different in May, August and November. 3-ring and 4-ring PAHs accounted for much more ecological risk than 2-ring, 5-ring and 6-ring, although the contributions of 5-ring and 6-ring to ecological risk were higher than these to PAHs concentrations. [ABSTRACT FROM AUTHOR]

The composition, structure, and dynamics of riparian vegetation are under great pressure from natural and anthropogenic disturbances. Regarding the riparian vegetation system, how to assess the effects of disturbances on system, analyze schemes of coupled disturbances and vegetation, and identify the significant effects are fundamental basis of corresponding management. This paper reviews the statistical, empirical, and analytical vegetation models, of which the assumptions, logic, and typical applicability are examined aiming at selecting the most appropriate model for a given case. This study suggests the current challenges of riparian vegetation modeling are as follows: (1) How to integrate multiple anthropogenic disturbances in riparian vegetation modeling for management decision support and (2) How to develop models that are suitable for multi-scale vegetation system that can reflect both long- and short-term effects under various disturbances. [ABSTRACT FROM AUTHOR]

The AQUATOX model considers the direct toxic effects of chemicals and their indirect effects through foodwebs. For this study, the AQUATOX model was applied to evaluating the ecological risk of Polybrominated diphenyl ethers (PBDEs) in a highly anthropogenically disturbed lake-Baiyangdian Lake. Calibration and validation results indicated that the model can adequately describe the dynamics of 18 biological populations. Sensitivity analysis results suggested that the model is highly sensitive to temperature limitation. PBDEs risk estimate results demonstrate that estimated risk for natural ecosystems cannot be fully explained by single species toxicity data alone. The AQUATOX model could provide a good basis in ascertaining ecological protection levels of “chemicals of concern” for aquatic ecosystems. Therefore, AQUATOX can potentially be used to provide necessary information corresponding to early warning and rapid forecasting of pollutant transport and fate in the management of chemicals that put aquatic ecosystems at risk. [Copyright &y& Elsevier]

Highlights: [•] Determined the potential ecological risk index of Cu, Ni, Pb, Zn, Hg, Cd, and Cr. [•] Analyzed the spatial–temporal variation of structural and functional metrics for benthic communities. [•] Developed and compared the correlation relationship between benthic communities metrics and risk index. [Copyright &y& Elsevier]

Highlights: [•] A conceptual model for the plain river ecosystem function in semiarid area and interfered by intensive human activities was developed. [•] The gray system model was improved. [•] Main functions of plain river ecosystem and the corresponding factors that determine the plain river ecosystem function were proposed. [Copyright &y& Elsevier]

Highlights: [•] The application of the AQUATOX model was based on the pelagic and benthic foodweb. [•] Calibration, sensitivity analysis and ecological risk assessment were carried out. [•] The model can determine ecological protection levels of “chemicals of concern”. [Copyright &y& Elsevier]

Abstract: We report the synthesis of MoV2O8 nanowires of high quality using spin coating followed by the thermal annealing process. Transmission electron microscopy (TEM) reveals the average diameter of synthesized nanowire about 100 nm, and average length ranges from 1 to 5 μm. The TEM analysis further confirms the <001> growth direction of MoV2O8 nanowires. The electrochemical properties of synthesized nanowires using cyclic voltammetry show the specific capacitance 56 Fg−1 at the scan rate of 5 mV s−1 that remains 24 Fg−1 at 100 mV s−1. The electrochemical measurements suggest that the MoV2O8 nanowires can be used as a material for the future electrochemical capacitors (energy storage devices). [Copyright &y& Elsevier]

Abstract: Ultrathin nanoflakes of Ni(OH)2 were synthesized onto multi-walled carbon nanotubes (MWCNTs) by simple low cost chemically precipitation method for high performance electrochemical supercapacitor applications. The synthesized ultrathin Ni(OH)2 exhibit high specific capacitance of 1735Fg−1 at a scan rate of 5mVs−1 with excellent rate capability. This high performance of Ni(OH)2 nanoflakes was attributed to its complete accessibility to the electrolyte and maximum utilization of metal hydroxides. Findings of this work suggest that synthesized electrodes offer low-cost and scalable solution for high-performance energy storage devices. [Copyright &y& Elsevier]

Abstract: Ecological risk assessment for water environment is significant to water resource management of basin. Effective environmental management and systems restoration such as the Haihe River Basin require holistic understanding of the relative importance of various stressor-related impacts throughout the basin. As an effective technical tool for evaluating the ecological risk, relative risk model (RRM) was applied in regional scale successfully. In this study, the risk transfer from upstream of basin was considered and the RRM was developed through introducing the source–stressor–habitat exposure filter (SSH), the endpoint–habitat exposure filter (EH) and the stressor–endpoint effect filter (SE) to reflect the meaning of exposure and effect more explicit. Water environment which includes water quality, water quantity and aquatic ecosystems was selected as the assessment endpoints. We created a conceptual model which depicting potential and effect pathways from source to stressor to habitat to endpoint. The Haihe River Basin estuary (HRBE) was selected as the model case. The results showed that there were two low risk regions, one medium risk region and two high risk regions in the HRBE. The results also indicated that urbanization was the biggest source, the second was shipping and the third was industry, their risk scores are 5.65, 4.71 and 3.68 respectively. Furthermore, habitat destruction was the largest stressor with the risk scores (2.66), the second was oxygen consuming organic pollutants (1.75) and the third was pathogens (1.75). So these three stressors were the main influencing factors of the ecological pressure in the study area. For habitats, open waters (9.59) and intertidal mudflat were enduring the bigger pressure and should be taken considerable attention. Ecological service values damaged (30.54) and biodiversity decreased were facing the biggest risk pressure. [Copyright &y& Elsevier]

Abstract: This paper compares water resource management policies between China and Denmark at the planning level. It takes two vulnerable freshwater bodies as a case study: Baiyangdian wetland in China and Mariager fjord in Denmark. It explores the commons and differences between the two ecosystems from the characteristics of the ecosystems, historical and cultural background of the society, the technologies affect the way the common is used, how the common is seen at different times, the existence of property rights through time and their development process. It also compares the environmental regulations and its impact on both water bodies. The analysis shows that both in Denmark and in China it can be expected that goals, once they are decided, will be implemented. But in reality it seems to be much easier to accomplish in Denmark than in China, probably due to the complicated administrative structure in China and clearer goals and better resources in Denmark. Denmark has also accomplished a large degree of environmental policy integration (EPI). But China has opened up the gate to the whole world and shows a positive attitude to participating in international affairs and environmental protection as well as sustainability. [ABSTRACT FROM AUTHOR]

Due to the growing energy demands, it is highly desirable to concurrently improve the thermal conductivity and dielectric breakdown strength of dielectric film capacitors. Polyvinylidene fluoride (PVDF) is hitherto regarded as a most satisfactory alternative for dielectric capacitors but with relatively low thermal conductivity and dielectric breakdown strength. Herein, a major contribution is made to the concurrent enhancement of PVDF-based thermal conductivity and dielectric properties. It can be readily achieved through the incorporation of as-prepared high-quality few-layered boron nitride nanosheets (BNNSs) with a minimized loading (defined as PVDF-BNNSs). BNNSs dispersion with intact structure and a large aspect ratio is prepared by a unique mild mechanical stirring process assisted by dimethyformamide/1-butanol (DMF/1-butanol) solvent and a low power ultrasonic. Encouragingly, the characteristic breakdown strength with a maximum value of 334 MV/m reaches for PVDF-BNNSs composite only with 3 vol% BNNS loading, to be 1.6 times of pure PVDF. It also presents a high discharged energy density up to 9.9 J cm-3, along with an efficiency of 68.3%. Synchronously, the thermal conductivity accomplishes a high value of 1.12 W/m·K with only 8 vol% BNNS loading. A further theoretical analysis reveals that high-quality appropriate BNNSs loading could be preferentially arranged in parallel with PVDF surface. It indicates that BNNSs have good interface compatibility with PVDF, thus to improve its associated performances concurrently. Image 1 [ABSTRACT FROM AUTHOR]

Per - and polyfluoroalkyl substances (PFASs) are emerging global environmental contaminants. Exploring the occurrence and environmental behavior of PFASs in the aquatic environment is a key step in solving global fluorine chemical pollution problems. In this study, surface water, pore water, and sediment were collected from the main tributary and the middle and lower reaches of the Daling River, adjacent to the Fuxin fluorochemical manufacturing facilities in Liaoning Province in China, to elucidate the occurrence and partition behavior of PFASs. The total concentrations of PFASs ranged from 48.4 to 4578 ng/L in the overlying water, from 173 to 9952 ng/L in the pore water, and from 2.16 to 40.3 ng/g dw in the sediment fraction. Generally, perfluorobutanoic acid (PFBA) and perfluorobutane sulfonate (PFBS) were the predominant congeners in the samples, with the mean relative content fractions being almost consistently >40% in the dissolved phase and >25% in the sediment. Hexafluoropropylene oxide dimer acid (HFPO-DA) and chlorinated polyfluorinated ether sulfonic acid (6:2 Cl-PFESA) were detected, albeit at low levels. In addition, the detection frequency and the contribution of legacy long-chain PFASs in sediment were higher than those in the overlying water and pore water. Except for perfluorohexane sulfonate (PFHxS), the concentrations of the alternative PFASs in the pore water were higher than in the overlying water. The organic carbon fraction was a more important controlling factor for PFAS sediment levels than cations content. As with legacy long-chain PFASs, HFPO-DA and 6:2 Cl-PFESA tended to partition into the solid phase, whereas short-chain PFASs were readily distributed in the aqueous phase. Such research results will be helpful in modeling the transport and fate of PFASs released by point sources into coastal waters through rivers and in developing effective risk assessment and management strategies for the control of PFAS pollution. Unlabelled Image • PFBS and PFBA were predominant in the overlying water, pore water and sediment in the Xi River-Daling River. • Alternatives were observed at higher concentrations in the pore water than in the overlying water. • Cations content had a lower impact on PFAS sediment levels when the organic carbon fraction was high enough. • As with PFOA and PFOS, HFPO-DA and 6:2 Cl-PFESA were prone to transfer from the aqueous phase to the solid phase. [ABSTRACT FROM AUTHOR]

• Assessed suitable water level for vegetation in different hydrological statues (DHS). • Considered vegetation response, resulted in vegetation dynamics model. • Above, linked to DHS, simulated alteration of vegetation patterns. • Considered vegetation pattern dynamics to assess partition of evapotranspiration. Hydrological regimes play a vital role in regulating wetland structure and function, regarded as fundamental for wetland protection and restoration. This study explored vegetation response to water-level dynamics, simulated vegetation patterns, and the estimated evapotranspiration (ET) pertaining to different hydrological statuses. We used the vegetation dynamics simulation model and topography- and vegetation-based surface energy partitioning algorithms (TVET model) designed to estimate potential evaporation (PE) and potential transpiration (PT). Results indicated that: (i) Vegetation cover and water levels of different hydrological statuses can be used to deduce suitable water levels during flood, normal, and drought statuses (which were 1.23, 0.99, and 0.81 m, respectively, in the Ertou wetland). (ii) Dynamic vegetation simulations combined with optimal ecological water levels for Phragmites australis and Bolboschoenus planiculmis sustenance can be used to simulate vegetation pattern dynamics. Both P. australis and B. planiculmis expanded during droughts along with a reduction in open water, providing a potential increase in food availability for Siberian crane (Grus leucogeranus). (iii) Changes in vegetation patterns and characteristics (e.g., plant height and leaf area index (LAI)) that varied with water-level fluctuations inevitably altered potential evapotranspiration (PET) partitioning into PE and PT. These results indicate that subtle water-level fluctuations can dramatically alter vegetation patterns, characteristics, and ecological processes, subsequently affecting shallow wetland habitats. Further investigations are necessary to clarify wetland coupling mechanisms between hydrology, vegetation, and habitat. This will help address extreme drought and flooding events while also helping to assess wetland protection and restoration. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag-alloyed CIGS absorbers fabricated by magnetron sputtering. • Different Ag thin layer incorporation locations. • A conversion efficiency of 10.2% is achieved for the ACIGS device with Ag at the bottom. • A highest power conversion efficiency of 13.01% is achieved after optimization. A sequential route for low-cost fabrication of high quality Ag-alloyed CIGS absorbers is reported. Ag-alloying is introduced into the CuInGa precursor to widen the band gap and improve the crystallinity of the ACIGS absorbers. The morphological, compositional, and structural characteristics of the ACIGS absorber are also systematically investigated. Different Ag thin layer incorporation locations at the bottom, in the middle and on the top of CuInGa precursors are schemed for deep understanding the band gap energy and crystallinity regulation mechanism of Ag alloying. A conversion efficiency of 10.2% is achieved for the ACIGS device with Ag at the bottom. The notable V oc improvement can be obtained due to the widened band gap and the band gap gradient in the absorber created by the Ag and Ga elements grading. Finally, the ACIGS absorbers are further sulfurized and a highest power conversion efficiency of 13.01% is obtained. Our results indicate that the sequential magnetron sputtering is a promising way for the fabrication of CIGS thin film solar cells. [ABSTRACT FROM AUTHOR]

Abstract: Sustainability is receiving increasing amounts of attention in higher education in terms of how it can best be integrated with university curricula. Sustainability is closely related to complexity, innovation, and interdisciplinarity; therefore, it requires alternative approaches rather than traditional, lecture-based pedagogy. This paper reports an educational initiative and research project based on collaboration between Beijing Normal University, China and Aalborg University, Denmark: developing a sustainability curriculum using the methodology of Problem and Project Based Learning (PBL) in a Chinese context. A theoretical framework is established to understand and analyze the culture's change toward a sustainability curriculum that employs PBL methodology. Empirical work is drawn upon first year results from the implementation of this methodology in an engineering and science curriculum. Data generation is based on multiple collection methods, such as survey of students' feedbacks, interviews with students, and analysis of students' project reports and reflection essays. This paper summarizes that a sustainability curriculum as proposed in this research can attract students' interests in not only mastering relevant knowledge, but also in developing necessary skills and competencies. PBL as a teaching and learning method can successfully facilitate participative learning, critical reflection, systemic thinking, creativity, and cultural awareness, which are the core values of sustainability. However, implementing a new curriculum with new teaching and learning methods can be more complex than expected. Many issues impact the implementation process and are therefore remain challenges to further development; for example, how to change the existing grading system, how to provide both teaching staff and students' with prior knowledge about the new PBL methods, how to gain institutional support, and how to change the broader societal and cultural values. [Copyright &y& Elsevier]

• Selenium-rich Sb 2 Se 3 amphous Sb 2 Se 3 film can be fabricated by sputtering selenium-rich Sb 2 Se 3 target at room temperture. • Amphous Sb 2 Se 3 Se-free annealing process was firstly used in Sb 2 Se 3 solar cell fabrication. • In this paper an open circuit voltage of 454 mV in substrate cofiguration structure Sb 2 Se 3 solar cell mV was obtained. Thin film solar cells of Sb 2 Se 3 undergo a significant carrier recombination loss, which impedes the further improvement of their efficiency. This is due to the intrinsic defects caused by selenium deficiency, such as the selenium vacancy and Sb Se antisite. Therefore, the selenium-enriched precursor film is effective in preventing the formation of this profound defect and improve the performance of the Sb 2 Se 3 thin film solar cells. However, there are only a very few reports that incorporate the use of a precursor to deposit Sb 2 Se 3 films. Herein, we initially prepared selenium-rich Sb 2 Se 3 films by sputtering selenium-rich Sb 2 Se 3 targets, and subsequently prepared the same films by simple annealing. It was observed that the substrate structure of the Sb 2 Se 3 thin film solar cell which was constructed by annealing at 400 °C had the best performance with an efficiency of 4.22% and an open circuit voltage (V oc) of 454 mV; this was a high V oc level for a Sb 2 Se 3 solar cell. The significant improvement of V oc represents a remarkable potential to improve the power conversion efficiency of Sb 2 Se 3 solar cells. [ABSTRACT FROM AUTHOR]

Dams are universally constructed to change hydrodynamic forces and impound water in urban rivers, but few efforts have been made to expound the impact of dams on the transport of antibiotics in rivers. In this study, the main object and focus was to elucidate the intercept effect of rubber dam and the gate dam on the sediment-water phase redistribution of eight typical antibiotics along an urban river with the water replenished from wastewater treatment plants (WWTPs). The results show that the eight antibiotics were widely detected in the whole river segment, and the WWTPs were found to be the main sources. Among the eight antibiotics, fluoroquinolones had the highest concentrations in the surface water, while tetracyclines constituted the dominant composition in the sediments. Due to the retention effect, the rubber dam encouraged the enrichment and degradation of the antibiotics in the river. However, the role of gate dams depended mainly on the opening and closing of the sluice gate. For all eight antibiotics, each dam or WWTP exhibited a generally consistent impact on the changes (e.g., an increase or decrease) of the sediment-water partitioning coefficients, although obvious differences existed between effect degree. Moreover, the changes in the coefficients caused by the rubber dam were completely opposite to those affected by gate dams. Contrary to the other six antibiotics, the two sulfonamides showed significant relationships with the dissolved organic matter in the surface water but had no significant relationships with the organic matter in the sediments. [ABSTRACT FROM AUTHOR]

A novel idea was presented by using patterned honeycomb-like ZnO cavities to enhance the light harvesting of Cu(In,Ga)Se 2 (CIGS) thin film solar cells in a broadband wavelength range. Large-scale patterned honeycomb-like ZnO cavities were fabricated through the versatile colloidal lithograhpy technique combined with the subsquent hydrothermal growth reaction. The growth mechanism was proposed based on the structural evolution of the patterned ZnO cavities. By introducing the patterned honeycomb-like ZnO cavities into CIGS solar cells, the performances of the device can be remarkabley improved due to the enhanced light harvesting. Photovoltaic device with a standard soda lime glass (SLG)/Mo/CIGS/CdS/i-ZnO/AZO/ZnO cavities/Ag grid structure exhibited a maximum power conversion efficiency of 11.4% under the standard AM 1.5 global illumination with a light intensity of 100 mW/cm 2 . An improvement of over 9.0% in the short-circuit photocurrent density and a 10.6% enhancement in the energy conversion efficiency were achieved compared with the standard reference device without ZnO cavities. More importantly, the device with patterned ZnO cavities exhibited omnidirectional behavior within a wide incident angle range. The enhancement of light harvesting is originating from the novel “negative” configuration of patterned ZnO cavities, which can realize high-efficient light trapping by multiple scattering and light coupling. [ABSTRACT FROM AUTHOR]

It is important to improve antibacterial properties and maintain desirable humidity of wound dressings. Herein, novel antibacterial wound dressings were prepared. Sulfonated SA, quaternized SA, and chlorogenic acid composited SA hydrogels were used and coated on Eucommia ulmoides rubber (EUR) films. These hydrogels were characterized by FTIR, SEM, zeta potential, swelling behavior and rheology. Moreover, the biocompatibility of the hydrogels was studied by fibroblast cells (L929). Then, the mechanical property and water vapor permeability of wound dressings were tested. Meanwhile, the drug release behavior of the wound dressings was determined by the Korsmeyer-Peppas model and their antibacterial effects on E. coli and S. aureus were studied. Finally, wound healing performance was evaluated by mouse full-thickness wounds model. After 11 days, the wound healing rates in the treatment groups can reach more than 90%, in particular, CGA-SA/EUR group had the highest healing rate of 98%. The results from histopathological observation and immunohistochemical staining showed these wound dressings could effectively promote the wound regeneration and repairing, indicating the wound dressings can be potentially used for accelerating wound healing. [Display omitted] • SSA, QSA and CGA-SA/EUR wound dressings were developed and characterized. • Drug release behavior was determined by the Korsmeyer-Peppas model. • Wound healing performance was evaluated by a mouse full-thickness wounds model. • It showed a high wound healing rate that can reach more than 90% after 11 days. [ABSTRACT FROM AUTHOR]

Abstract: There are a large number of interactions at molecular and cellular levels between the plant polysaccharides and immune system . Plant polysaccharides present an interesting effects as immunomodulators, particularly in the induction of the cells both in innate and adaptive immune systems . Activation of DCs could improve antitumoral responses usually diminished in cancer patients, and natural adjuvants provide a possibility of inducing this activation. ABP is a purified polysaccharide isolated from Achyranthes bidentata, a traditional Chinese medicine (TCM) . The aim of this study is to investigate modulation of phenotypic and functional maturation of murine DCs by ABP. Both phenotypic and functional activities were assessed with use of conventional scanning electronic microscopy (SEM) for the morphology of the DC, transmitted electron microscopy (TEM) for intracellular lysosomes inside the DC, cellular immunohistochemistry for phagocytosis by the DCs, flow cytometry (FCM) for the changes in key surface molecules, bio-assay for the activity of acidic phosphatases (ACP), and ELISA for the production of pro-inflammatory cytokine IL-12. In fact, we found that purified ABP induced phenotypic maturation revealed by increased expression of CD86, CD40, and MHC II. Functional experiments showed the down-regulation of ACP inside DCs (which occurs when phagocytosis of DCs is decreased, and antigen presentation increased with maturation). Finally, ABP increased the production of IL-12. These data reveal that ABP promotes effective activation of murine DCs. This adjuvant-like activity may have therapeutic applications in clinical settings where immune responses need boosting. It is therefore concluded that ABP can exert positive modulation to murine DCs. [Copyright &y& Elsevier]

Self-designed selenium thermal-cracking system is used to produce selenium vapor with high activity for sufficient selenization of CZTSSe absorber. CZTS precursor film prepared by magnetron sputtering of CZTS quaternary target. By adjusting the heating temperature of selenium source to 600 °C, macromolecular Se n can be cracked to small molecule Se n with high reaction activity, which is helpful to form densely packed large grains in the CZTSSe absorber due to the reduction of selenium vacancies and the enhancement of surface migration. The crystallization quality of CZTSSe absorber is further improved by the optimization of selenium source heating rate. A peak performance of solar cells achieved exhibiting a power conversion efficiency of 7.9%, with V oc of 410 mV, J sc of 35.25 mA/cm2 and FF of 54.98%. J-V characterization, electrochemical impedance spectra and capacitance-voltage tests are also employed to analysis the device performance enhancement mechanism. • Selenium vapor with high activity for sufficient selenization. • Macromolecular Se n (n ≥ 5) can be cracked to small molecule Se n with high reaction activity. • Higher suppression ability for carrier recombination. • Inherent performance enhancement mechanism. [ABSTRACT FROM AUTHOR]