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The waste electrical and electronic equipment (WEEE) recycling industry in China has been booming since the beginning of the millennium and plays a critical role in pollution control and resource efficiency. And the fast growth of the WEEE recycling industry reflects the development of China's circular economy. This paper gives an outline of China's circular economy with respect to law-making actions and promotional measures, including the implementation of clean production and the building-up of recycling and remanufacturing parks. In addition, it reviews the roadmap of China's WEEE recycling industry as an example of circular economy development. Furthermore, the current status of China's WEEE recycling industry is introduced and its social-economic impacts are discussed. Finally, trends and challenges surrounding WEEE recycling and the circular economy in China are presented. [ABSTRACT FROM AUTHOR]

This study investigates the optimization of taxi-pooling operations using the M/M/1/m queuing model, aiming to enhance efficiency and revenue for taxi service platforms. Traditional taxi operations face challenges during peak periods, including inefficiency and increased operational costs. Taxi-pooling, by accommodating multiple passengers with similar travel demands, offers a solution that reduces travel costs, operational expenses, and urban congestion. The study develops an optimization model to balance operational costs and passenger waiting times, identifying the utilization rate of taxis as a critical factor in platform revenue. By modeling the taxi-pooling service as a queuing system, we derive mathematical expressions for passenger waiting times and platform revenue under varying conditions. Our findings highlight the importance of optimal vehicle investment strategies and pricing decisions to maximize revenue. The study provides theoretical support for improving taxi-pooling platforms' efficiency and competitiveness, contributing to better urban transportation solutions. [ABSTRACT FROM AUTHOR]

The capacity of carbon sinks varies among the different types of ecosystems, and whether national parks, as an important type of nature reserve, have a high carbon sink capacity (CSC) and whether eco-tourism in national parks affects their CSC are the main scientific issues discussed. Using MODIS Net Primary Production (NPP) product data, this study analysed the spatiotemporal variation in carbon sources and sinks (CSSs) in the ecosystem of Huangshan National Park from 2000 to 2020, as well as the impact of tourism on these carbon sources and sinks. The findings indicate that, while the ecosystems of national parks generally have a strong CSC, they may not always function as carbon sinks, and during the study period, Huangshan National Park served as a carbon source for four years. Temporally, the CSSs in the ecosystem of the national park exhibit a cyclical pattern of change with a four-year cycle and strong seasonality, with spring and autumn functioning as carbon sinks, and summer and winter as carbon sources. Spatially, the CSSs of the national park ecosystem exhibited a vertical band spectrum of spatial distribution, and the CSC showed a trend of gradual enhancement from low altitude to high altitude. Tourism is a major factor that has an impact on the CSC of national park ecosystems. [ABSTRACT FROM AUTHOR]

Bifacial photovoltaic sunshade (BiPVS) is an innovative building-integrated photovoltaic (BIPV) technology. Vertically mounted BiPVS is capable of converting part of the incident solar radiation into electricity, regulating the indoor heat gain from solar penetration and improving daylighting. An excellent BiPVS design should comprehensively consider its impact on building performance and economic viability. This study aims to address this issue by proposing a parametric design-based multi-objective optimization (MOO) framework to maximize indoor useful daylight illuminance, minimize air-conditioning energy consumption, and shorten the payback period by optimizing BiPVS design parameters. The framework utilizes the Ladybug, Honeybee, and Wallacei plugins on the Rhino-Grasshopper simulation platform. It validates the optimization potential of BiPVS in a typical office located in a hot summer and warm winter zone. The results indicate that BiPVS has significant energy-saving and daylighting potential. Compared to the baseline model without BiPVS, useful daylight illuminance is increased by 39.44%, air-conditioning energy consumption is reduced by 12.61%, and the economically satisfactory payback period is 4.80 years. This study provides a practical solution for the competing objectives of daylighting and energy saving in buildings with significant renewable energy utilization. The developed framework is highly efficient and versatile and can be applied to other BIPV designs, which benefits the realization of carbon-neutral goals in the building sector. [ABSTRACT FROM AUTHOR]

The development of e-commerce and the green economy has prompted suppliers of green products to introduce internet channels by which products are directly sold to consumers. However, the emergence of "price wars" and "free riding" between the two channels after the introduction of online channels may affect the stability of the green supply chain. This paper uses optimization theory to investigate the impact of service spillover effects and different channel structures on the optimal decision of supply chain members in a Stackelberg game. By comparing the equilibrium outcomes of the single-channel and dual-channel supply chain in a setting with and without retail services, we observe that the supplier prefers to encroach on the market when services that retail locations provide largely spillover to and benefit the direct sales channel. Contrary to popular belief, a higher degree of service spillovers is beneficial for the retailer to achieve more returns under the dual-channel structure, whereas supplier encroachment will lead to a decline in the service level if the spillover degree is relatively low. In addition, the emission reduction level of products under supplier encroachment is always higher than that employed in the single-channel structure if consumers have both low-carbon preference and a high degree of service sensitivity. Finally, we expand our discussion by introducing the carbon cap-and-trade (CCT) mechanism to compare the conditions for achieving Pareto improvement under supplier encroachment. These results can provide helpful insights for decision-makers in supply chain management to implement effective channel selection and achieve sustainable development. [ABSTRACT FROM AUTHOR]

This article proposes an improved wavelet threshold denoising for laser self-mixing interference signals. The improved wavelet threshold function exhibits smoothness and continuity near the threshold. By replacing hard or soft wavelet threshold with the improved wavelet threshold, it can eliminate the generation of fake self-mixing interference peaks due to local oscillation induced by hard wavelet threshold, as well as the loss of self-mixing interference peaks due to over-smoothness induced by the soft wavelet threshold. Compared with hard and soft wavelet threshold denoising, theoretical simulations and experimental results demonstrate that the displacement of vibrations are well reconstructed based on the improved wavelet threshold denoising. [ABSTRACT FROM AUTHOR]

Dismantling the waste printed circuit boards (WPCBs) of obsolete mobile phones is essential for resource recycling and environmental protection. An automated WPCB disassembly equipment based on the hot-vibration process was designed and applied, with optimized process conditions of a heating temperature of 250 °C and an equipment amplitude of >3.66 mm. The dismantling rate for electronic components and metal shields was 98%, but disassembly of components with underfill was less effective. Both simulation and actual measurement results of the equipment's thermal field showed that the temperature inside the disassembly bin was uniform, with a maximum temperature difference of 6–8 °C. The area of the low-temperature region accounted for approximately 5% of the total area. The acceleration ranged from 2.11 to 8.28 g when using the disassembly force model. This equipment and process can be applied to disassemble large quantities of WPCBs. [ABSTRACT FROM AUTHOR]

This article described the implementation of rotational Bloch boundary conditions in photonic devices using the finite element method (FEM). For the electromagnetic analysis of periodic structures, FEM and Bloch boundary conditions are now widely used. The vast majority of recent research, however, focused on applying Bloch boundary conditions to periodic optical systems with translational symmetry. Our research focused on a flexible numerical method that may be applied to the mode analysis of any photonic device with discrete rotational symmetry. By including the Bloch rotational boundary conditions into FEM, we were able to limit the computational domain to the original one periodic unit, thus enhancing computational speed and decreasing memory consumption. When combined with the finite-element method, rotational Bloch boundary conditions will give a potent tool for the mode analysis of photonic devices with complicated structures and rotational symmetry. In the meantime, the degenerated modes we calculated were consistent with group theory. Overall, this study expands the numerical tools of studying rotational photonic devices, and has useful applications in the study and design of optical fibers, sensors, and other photonic devices. [ABSTRACT FROM AUTHOR]

As a novel reaction mode of oxidative dehydrogenation of ethane to ethylene, the chemical looping oxidative dehydrogenation (CL-ODH) of ethane to ethylene has attracted much attention. Instead of using gaseous oxygen, CL-ODH uses lattice oxygen in an oxygen carrier or redox catalyst to facilitate the ODH reaction. In this paper, a perovskite type redox catalyst LaMnO3+δ was used as a substrate, Ce3+ with different proportions was introduced into its A site, and its CL-ODH reaction performance for ethane was studied. The results showed that the ratio of Mn4+/Mn3+ on the surface of Ce-modified samples decreased significantly, and the lattice oxygen species in the bulk phase increased; these were the main reasons for improving ethylene selectivity. La0.7Ce0.3MnO3 showed the best performance during the ODH reaction and showed good stability in twenty redox cycle tests. [ABSTRACT FROM AUTHOR]

The unbalanced nature of passenger demand and the uncertainty of delay at intersections are considered critical factors in the efficiency of public transportation operations. Considering the controllable characteristics of the bus rapid transit system (BRT), an integrated optimization model that includes multi-mode transit scheduling and signal timing is proposed. The robust optimization model copes with the fluctuations in passenger demand and bus operation. A non-linear programming is developed to minimize the total passenger travel time and optimize the transit departure time, dwelling strategies at stations, and signal timings at intersections. The constraints on the signal control, degree of saturation, transit scheduling, and passenger waiting time at stations are intended to reflect real traffic conditions. A case study and extensive sensitivity analyses were conducted to evaluate the performance of the proposed model. The results show that the proposed integrated model can adjust the BRT dwelling strategies based on different passenger demands and coordinate transit departure time and signal timing adjustment to mitigate the passenger delay. Furthermore, experimental results demonstrate improvements of 5.3% and 8.1% in the mean and maximum values of passenger travel time, respectively, using the proposed model, compared to those obtained using the conventional operation strategy. [ABSTRACT FROM AUTHOR]

Since the Anthropocene, drastic changes in the relationship between humans and the earth have prompted human beings to pay more attention to the living environment. As a metaphor to reveal the state of humanity and nature, ecosystem health has gradually become an important issue closely related to global sustainable development ever since it was widely discussed in the 1990s. This study reviewed 4354 publications about ecosystem health from the Web of Science Core Collection by using CiteSpace software. In addition, 135 empirical papers were selected to further analyze the evaluation methods and characteristics of ecosystem health. This study was able to answer four questions: (1) What are the definitions, research content, and characteristics of ecosystem health? (2) Are there any features during the different periods of the development of the ecosystem health? Are there geographical differences in the research? (3) What are the methods and cases selected for studying ecosystem health, and under what kind of conditions do they apply? Are there any patterns or characteristics in the use of these methods? (4) What are the gaps and deficiencies in ecosystem health research, and where should we set our focus on in the future? In general, this study combined bibliometric analysis with a systematic review method, aiming to summarize the current status of ecosystem health research, make up for the deficiencies in the current review, and put forward new insights regarding the concept cognition, evaluation, and future outlook of ecosystem health research. [ABSTRACT FROM AUTHOR]

Urban vegetation coverage is a core index in urban planning, which has been confirmed to be an effective indicator for the urban thermal environment. Through the urban thermal environment, this study aims to further quantify the impact of vegetation coverage on urban energy consumption. Chenzhou, a typical hilly city, was selected as the study object for its diversified vegetation coverages. Remote sensing technology and correlation and regression models were employed in this study. Firstly, the data of land surface temperature and vegetation coverage were calculated with remote sensing technology, followed by data analysis with the correlation and regression models. Then, employing the "λ-T" model, a statistical model corresponding to urban temperature and energy, this study clarified the impact of temperature on urban energy consumption. Finally, through urban temperature, this study analyzed the impact of urban greening coverage on urban energy consumption. This study shows that when the temperature ranges from 22 °C to 28.9 °C, every 10% of additional vegetation coverage will reduce the air conditioning energy demands by 5.5%, and when the temperature is between 28.9 °C and 37 °C, every 10% of additional vegetation coverage will reduce the mean air conditioning energy demands by 2.4%. [ABSTRACT FROM AUTHOR]

Label Propagation Algorithm (LPA) is a fast community detection algorithm. However, since each node is randomly assigned a different label at first, there is serious randomness in the label updating process of LPA, resulting in great instability of detection results. This paper proposes a modularity-based incremental LPA (MILPA) to address this problem. Unlike LPA, MILPA first assigns all nodes the same label, and then repeatedly uses divide strategy to split locally dense connected nodes into a community and give them a new label. After that, MILPA uses modularity gain as the optimization function to fine-tune the label of nodes so as to obtain an optimal partition. The proposed MILPA has been compared with LPA and other known methods. Experimental results show that MILPA has the best and most stable performance in LFR benchmark networks and is comparable to the best algorithm in many real networks. [ABSTRACT FROM AUTHOR]

This study aimed to expound the changes in soil water flow, heat transport, and tomato production under micro-sprinkler irrigation and plastic film (MSPF) conditions. The effects of different irrigation amounts (I1:0.7 Epan; I2:1.0 Epan; and I3:1.2 Epan (Epan is the cumulative evaporation from a 20 cm diameter standard pan, mm)) on soil water, soil temperature, and tomato yield were studied. A completely randomized trial design was used; meanwhile, the drip irrigation under plastic film (CK1) and micro-sprinkler irrigation without mulch film (CK2) were used as controls. The results showed that the shape of soil moisture was banded under MSPF; the soil wetting range was larger than that of CK1 and CK2 in the profile of MSPF. The change range of 5 cm soil temperature of MSPF 1–5 days after irrigation was 4.05 °C. The change range of 5 cm soil temperature of MSPF was lower than that of CK1 from 1 to 5 days after irrigation. During the growth period of spring and autumn tomato, the average soil moisture content of 0–40 cm with CK1 was 1.97% and 3.83% (spring and autumn, respectively) higher than that of MSPF, and the average soil temperature of 5–25 cm was 2.36% and 1.66% (spring and autumn, respectively) lower than that of MSPF. Compared with CK2, the average soil moisture content of 0–40 cm under MSPF increased by 8.30% and 3.83% (spring and autumn, respectively), and the average soil temperature of 5–25 cm under MSPF increased by 5.85% and 1.68% (spring and autumn, respectively). The spring and autumn tomato yield of MSPF was significantly higher than that of CK1 by 19.39% and 4.54%, respectively. The spring and autumn tomato yield of MSPF were higher than that of CK2 by about 20.46% and 49.22%, respectively. With an increase in the irrigation amount of MSPF, the soil moisture and yield of spring and autumn tomato increase; the soil temperature and water use efficiency of spring and autumn tomato decrease. Considered comprehensively, the MSPF can be used as one of the methods of greenhouse tomato micro-irrigation, and 1.0 Epan is recommended for irrigation parameters in northwest China facility agriculture. [ABSTRACT FROM AUTHOR]

Agriculture is a major source of global greenhouse gas emissions. Approximately 1/3 of vegetables in China are produced in greenhouses. However, the effects of different irrigation strategies and plastic film (PF) mulching combinations on N2O emissions and tomato fruit yields in greenhouses are unclear. The aims of this study were to explore the effects of micro-sprinkler irrigation under plastic film (MSPF), drip irrigation under plastic film (DIPF) and micro-sprinkler irrigation (MSI) on the soil nutrients, enzyme activity, nirS-type denitrifying bacterial community, N2O emissions and fruit yields of tomato. The results showed that MSPF could improve the uniformity of soil water distribution and surface (0–40 cm) soil water content. Film mulching could increase soil temperature at depths of 5–25 cm. Both MSPF and DIPF increased microbial nitrogen, promoted the activity of rhizosphere soil urease and leucine aminopeptidase, changed the community of denitrifying bacteria, accelerated the turnover of soil nutrients and improved yield and water use efficiency. PF mulching had a greater impact on the nirS-type denitrifying bacterial community when compared to irrigation strategy. We conclude that MSPF can be used to configure commercially available installation and operation. The comprehensive benefit of MSPF treatment is that it is more profitable than that of DIPF. [ABSTRACT FROM AUTHOR]

Soil aeration and plastic film mulching have been reported to accelerate plant growth and increase fruit yield by improving the rhizosphere soil–air environment. The aim of this study was to investigate plant growth, fruit yield, irrigation water-use efficiency (IWUE) and fruit quality in response to a micro/nano-bubble aeration (MNBA) system and a subsurface artificial air layer aeration system (SAALA) under different treatments. The results indicated that both MNBA and SAALA positively influenced the plant dry weight, fruit yield, IWUE and fruit quality. In comparison with the no aeration treatment, the MNBA treatment increased the dry matter accumulation, fruit yield, IWUE, lycopene content and soluble protein content by 7.1%, 9.0%, 7.1%, 6.2% and 16.2%, respectively. Plastic film mulching (PFM) significantly improved the total dry weight, fruit yield and IWUE during both seasons. The increased yield in response to soil aeration during autumn was significantly greater than that during spring, and the yield increase in response to PFM was significantly greater in spring than in autumn. Moreover, the nutrition indices in response to both soil aeration and PFM were more significant during spring than autumn. Taking into account costs, efficiency and benefits, the optimal treatment was the MNBA and full (F) PFM combination. [ABSTRACT FROM AUTHOR]

The paper describes one promising method and approach for the recycling, reuse, and co-resource treatment of waste photovoltaic silicon and lithium battery anode graphite. Specifically, this work considers the preparation of nano/micron silicon carbide (SiC) from waste resources. Using activated carbon as a microwave susceptor over a very short timeframe, this research paper shows that nano/micron β-SiC can be successfully synthesized using microwave sintering technology. The used sintering temperature is significantly faster and more energy-efficient than traditional processes. The research results show that the β-SiC particle growth morphology greatly affected by the microwave sintering time. In a short microwave sintering time, the morphology of the β-SiC product is in the form of nano/micron clusters. The clusters tended to be regenerated into β-SiC nanorods after appropriately extending the microwave sintering time. In the context of heat conversion and resource saving, the comprehensive CO2 emission reduction is significantly higher than that of the traditional SiC production method. [ABSTRACT FROM AUTHOR]

Tomato is an important economic crop that is widely consumed worldwide. Tomato production is mainly limited by the use of nitrogen fertilizer, sunlight, soil and water conditions. Biochar is one of the soil amendments, and it is recognized as a promising practice for improving crop production in agriculture. The effect of biochar on the photosynthetic traits and tomato yield under reduced nitrogen fertilizer application is still not well understood. The objective of this research is to investigate the influence of biochar application on the photosynthesis and yield of tomato under reduced nitrogen fertilizer application from the perspectives of the nutrient uptake of plants (nitrogen and phosphorus), leaf photosynthetic pigment and leaf gas exchange parameters. Two-year greenhouse experiments containing six biochar levels (0, 10, 30, 50, 70, and 90 t ha−1) and two nitrogen fertilizer application rates (190 and 250 kg ha−1) were conducted. Compared with C0, C50 significantly improved the nitrogen uptake (74–80%) and phosphorus uptake (76–95%) by tomato plants and further enhanced the photosynthetic traits of tomato leaves (net photosynthetic rate (Pn), stomatal conductance (gs), transpiration rate (Tr) and chlorophyll (2–60%), which lead to the highest gains in tomato yield (more than 50%) even when the applied nitrogen fertilizer was significantly reduced (from 250 kg ha−1 to 190 kg ha−1). The photosynthesis rate had a linear correlation with the total nitrogen and phosphorus accumulation and tomato yield. The results will enhance our understandings about the effect of biochar on the photosynthesis and yield of tomato and be of importance for practical agricultural management. [ABSTRACT FROM AUTHOR]

Ultrafiltration is widely employed in treating high-salinity organic wastewater for the purpose of retaining particulates, microbes and macromolecules etc. In general, high-salinity wastewater contains diverse types of saline ions at fairly high concentration, which may significantly change foulant properties and subsequent fouling propensity during ultrafiltration. This study filled a knowledge gap by investigating polysaccharide fouling formation affected by various high saline environments, where 2 mol/L Na+ and 0.5–1.0 mol/L Ca2+/Al3+ were employed and the synergistic influences of Na+-Ca2+ and Na+-Al3+ were further unveiled. The results demonstrated that the synergistic influence of Na+-Ca2+ strikingly enlarged the alginate size due to the bridging effects of Ca2+ via binding with carboxyl groups in alginate chains. As compared with pure alginate, the involvement of Na+ aggravated alginate fouling formation, while the subsequent addition of Ca2+ or Al3+ on the basis of Na+ mitigated fouling development. The coexistence of Na+-Ca2+ led to alginate fouling formed mostly in a loose and reversible pattern, accompanied by significant cracks appearing on the cake layer. In contrast, the fouling layer formed by alginate-Na+-Al3+ seemed to be much denser, leading to severer irreversible fouling formation. Notably, the membrane rejection under various high salinity conditions was seriously weakened. Consequently, the current study offered in-depth insights into the development of polysaccharide-associated fouling during ultrafiltration of high-salinity organic wastewater. [ABSTRACT FROM AUTHOR]

The tomato is an important economic crop that is a main ingredient of some prepared food as well as a focus of the agricultural industry. Optimizing nitrogen (N) fertilizers is essential for sustainable agricultural development, while the excessive use of N fertilizers leads to environmental and food production problems. As a soil amendment, biochar has been widely used to improve soil quality and crop yield. However, little information is available on the effects of biochar and N fertilizer reduction on tomato plant, soil characteristics in tomato cultivation and tomato production. In this study, a greenhouse experiment was carried out in Yangling, Shaanxi province, China, including four biochar levels (0, 30, 50, and 70 t ha−1) under drip irrigation and four N application rates (170, 190, 210, and 250 kg ha−1). The results showed that adding too much biochar (e.g., 70 t ha−1) and reducing N fertilizer too far (e.g., by 32%) will not lead to satisfactory results in terms of tomato growth, tomato yield and quality, and economic benefits. Biochar addition could significantly enhance microbial abundance, enzyme activity, and tomato growth compared with non‒biochar treatments when reducing the amount of applied N fertilizer by 16% or 24% (N2 and N3). From the perspectives of tomato yield, tomato quality (sugar‒acid ratio and vitamin C (VC) content), and economic benefits, optimal application rate of biochar and N fertilizer based on the silty clay loam soil of northwest China under drip irrigation is proposed, respectively. The proposal is based on both multidimensional nonlinear regression models and a comparison with experimental treatments. For example, biochar addition at 50 t ha−1 and reducing N fertilizer by 24% achieved the greatest tomato yield. Compared with non-biochar treatment under the corresponding N fertilizer level, soil enzyme activity (urease, phosphatase, and catalase), microbial abundance (bacteria, fungi, and actinomycetes), leaf gas exchange parameters (gs, Pn, and Tr), and biomass increased on average by 88.76%, 7.49%, 43.23%, and 39.67%, respectively. Based on a comprehensive consideration of tomato yield, VC content, sugar‒acid ratio, and economic benefits, 35 t ha−1 biochar and 200 kg ha−1 N fertilizer is the recommended combination of biochar and nitrogen fertilizer for local farmers. [ABSTRACT FROM AUTHOR]

Baseline drift spectra are used for quantitative and qualitative analysis, which can easily lead to inaccurate or even wrong results. Although there are several baseline correction methods based on penalized least squares, they all have one or more parameters that must be optimized by users. For this purpose, an automatic baseline correction method based on penalized least squares is proposed in this paper. The algorithm first linearly expands the ends of the spectrum signal, and a Gaussian peak is added to the expanded range. Then, the whole spectrum is corrected by the adaptive smoothness parameter penalized least squares (asPLS) method, that is, by turning the smoothing parameter λ of asPLS to obtain a different root-mean-square error (RMSE) in the extended range, the optimal λ is selected with minimal RMSE. Finally, the baseline of the original signal is well estimated by asPLS with the optimal λ. The paper concludes with the experimental results on the simulated spectra and measured infrared spectra, demonstrating that the proposed method can automatically deal with different types of baseline drift. [ABSTRACT FROM AUTHOR]

The objective of this study was to reveal the regulatory mechanisms underlying the soil bacterial community of subsurface drip irrigation (SDI). The effect of different buried depths of drip tape (0, 10, 20, 30 cm) on the soil bacterial community in a tomato root-zone was investigated using high-throughput technology. Furthermore, the mutual effects of root growth, tomato yield and soil bacterial community were also analyzed to explore the response of root-soil interaction to the buried depth of drip tape. The results indicated that SDI (i.e., 10, 20 and 30 cm buried depths of drip tape) changed the soil bacterial community structure compared to surface drip irrigation (a 0 cm buried depth of drip tape). SDI with a 10 cm buried depth of drip tape significantly reduced the relative abundances of Proteobacteria, Chloroflexi, Gemmatimonadetes, Acidobacteria, Firmicutes and Planctomycetes, but significantly increased the relative abundances of Actinobacteria, Candidate_division_TM7 and Bacteroidetes. SDI of 20 and 30 cm buried depth significantly decreased the relative abundances of Roteobacteri, Actinobacteria and Planctomycetes, however, increased the relative abundances of Chloroflexi, Gemmatimonadetes, Acidobacteria, Firmicutes, Candidate_division_TM7 and especially some trace bacteria (for example Nitrospirae). Furthermore, under 20 cm or 30 cm of buried depth, the abundances of nitrogen metabolism and phosphonate and phosphinate metabolism based on the PICRUSt (Reconstruction of Unobserved States) method were significantly improved as well as soil porosity and root forks at 0-10 cm. These changes strengthened root-soil interaction and improved tomato yield per plant by 22.47% and 19.38% under 20 cm and 30 cm of buried depth, respectively, compared to surface drip irrigation. Therefore, the responses of bacterial community and root-soil interaction to drip tape buried depth of 20 cm and 30 cm are proven to be beneficial for the increasing of tomato production. [ABSTRACT FROM AUTHOR]

Alternate drip irrigation (ADI) is a useful irrigation method for water conservation and the regulation of soil quality; however, knowledge about the underlying mechanism of soil-root-bacterium interactions is limited. To determine the mechanism by which ADI transforms soil nutrients and thereby promotes plant growth and to provide a basis for the reasonable selection of drip irrigation methodology, the present study investigated the effects of ADI on the composition and potential function of the bacterial community in tomato rhizosphere soils under greenhouse conditions and analyzed the soil-root-bacterium interactions under ADI. The results revealed that, compared with the soils of the plots treated with surface drip irrigation with plastic film mulching (DI-PFM), the soils of the plots treated with ADI presented an optimized bacterial community structure and optimized soil nitrogen (N) and phosphorus (P) metabolism. The soil available N contents under ADI with lower irrigation limits of 50%, 60%, and 70% of field capacity (A50, A60, and A70 treatments, respectively) were 1.48, 2.19, and 1.91 times greater than those under DI-PFM, respectively; similarly, the soil available P contents were 1.49, 1.65, and 2.91 times greater; the total phosphorus (TP) contents in the tomato roots were 1.06, 1.94, and 1.59 times greater, respectively; and the TP contents in the tomato plants were 1.03, 1.75, and 2.84 times greater, respectively. In addition, the total nitrogen (TN) contents in the tomato roots under ADI with lower irrigation limits of 60% and 70% of field capacity were 1.07 and 1.14 times greater than those under DI-PFM, and the TN contents in the tomato stems were 1.21 and 1.12 times greater than those under DI-PFM. However, compared with DI-PFM, ADI improved tomato yields by 24.23% under only 70% of field capacity. Therefore, ADI significantly enhanced soil-root interactions and stimulated the activation of soil N and P, but only a proper low soil moisture content (SMC) led to significantly increased tomato yields. [ABSTRACT FROM AUTHOR]

An experiment was conducted in China to develop guidelines for the mulching drip irrigation of commercial muskmelon crops. Three sets of factors were laid out in rows to give a three × three factorial design. First, plastic covers were placed over the entire growing area (rows and inter-rows, or full), over the rows (half), or no plastic applied (none). Second, there was one irrigation pipe per row (T1), three pipes for four rows (T3/4), or one pipe for two rows (T1/2). Finally, the plants were irrigated when the soil water content fell to 60%, 70%, or 80% of field water capacity (FC). Information was collected on net CO2 assimilation (Pn), plant growth, and yield. Overall, maximum Pn occurred with half plastic covering, one irrigation pipe for two rows, and irrigation at 80% FC. Plant fresh weight was higher with half plastic covering, one irrigation pipe per row, and irrigation at 70% or 80% FC. Yield was higher with half plastic covering, and irrigation at 70% or 80% FC. There were only small differences in the yield across numbers of irrigation pipes. These results suggest that overall productivity was better with plastic covers over the rows and irrigation at 70% or 80% FC. Differences in productivity with different numbers of irrigation lines per row were small. [ABSTRACT FROM AUTHOR]

Biomass thermochemical conversion with in situ CO2 capture is a promising technology in the production of high-quality gas. The adsorption competition mechanism of gas molecules (H2O, CO2, CO, CH4, and H2) on CaO-based catalyst surfaces was studied using density functional theory (DFT) and experimental methods. The adsorption characteristics of CO2 on CaO and 10 wt % Ni/CaO (100) surfaces were investigated in a temperature range of 550–700 °C. The adsorption energies were increased and then weakened, reaching their maximum at 650 °C. The simulation results were verified by CO2 temperature-programmed desorption (CO2-TPD) experiments. By the density of states and Mulliken population analysis, CaO doped with Ni caused a change in the electronic structure of the Osurf atom and decreased the C–O bond stability. The molecular competition mechanism on the CaO-based catalyst surface was identified by DFT simulation. As a result, the adsorption energies decreased in the following order: H2O > CO2 > CO > CH4 > H2. The increase of CO2 adsorption energy on the 10 wt % Ni/CaO surface, compared with the CaO surface, was the largest among those of the studied molecules, and its value increased from 1.45 eV to 1.81 eV. Therefore, the 10 wt % Ni/CaO catalyst is conducive to in situ CO2 capture in biomass pyrolysis. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) is an important advanced additive manufacturing technology. The existing SLM products cannot fully meet the requirements of high-precision and strength of the mechanical component because of their defects. The TiAlN/TiN multilayer coating can improve the surface property of SLM products. The present work aims to explore the influences of different process parameters of SLM on the property of TiAlN/TiN multilayer coating plating on the 361L specimen and the mechanism of these influences. Taking laser power, scanning speed, and scanning space as factors, an orthogonal experiment was designed. The TiAlN/TiN multilayer coating specimens can be obtained by plating on the 361L specimen, fabricated by the process parameters of SLM on the orthogonal experiment. The surface topographies and properties of TiAlN/TiN multilayer coating were tested, the influences of SLM process parameters on TiAlN/TiN multilayer coating were analyzed, and the optimal process parameter was obtained. The electron microscope images revealed that the surface morphology of TiAlN/TiN multilayer coating plating on the SLM specimen was relatively flat, and there were some macro-particles in different sizes and pin holes dispersed on it. The thickness of the TiAlN/TiN multilayer coating was 2.77–3.29 μm. The microhardness value of coating SLM specimen was more than four times that of the uncoated SLM specimen and the wear rates of the uncoated specimen were 2–4 times that of the corresponding coating specimen. The comprehensive analysis shows that the laser power had the greatest influence on the comprehensive property of the coating. The primary cause of the influence of SLM process parameters on the properties of the TiAlN/TiN multilayer coating was preliminarily discussed. When the laser power was 170 W, the scanning speed was 1,100 mm/s, and the scanning space was 0.08mm, the TiAlN/TiN multilayer coating plating on the SLM specimen had the best comprehensive property. [ABSTRACT FROM AUTHOR]

With 1-methyl-2-pyrrolidinone (NMP) as the solvent, the biodegradable gel polymer electrolyte films are prepared based on poly(vinyl alcohol) (PVA), lithium bis(trifluoromethane)sulfonimide (LiTFSI), and 1-ethyl-3 methylimidazoliumbis(trifluoromethylsulfonyl)imide (EMITFSI) by means of solution casting. The films are characterized to evaluate their structural and electrochemical performance. The 60PVA-40LiTFSI + 10 wt.% EMITFSI system exhibits excellent mechanical properties and a high ionic transference number (0.995), indicating primary ionic conduction in the film. In addition, because of the flexibility of polymer chain segments, its relaxation time is as low as 5.30 × 10−7 s. Accordingly, a high ionic conductivity (3.6 × 10−3 S cm−1) and a wide electrochemical stability window (~5 V) are obtained. The electric double-layer capacitor (EDLC) based on this electrolyte system shows a specific capacitance of 101 F g−1 and an energy density of 10.3 W h kg−1, even after 1000 charge-discharge cycles at a current density of 0.4 A g−1 under a charging voltage of 2 V. All these excellent properties imply that the NMP-soluble 60PVA-40LiTFSI + 10 wt.% EMITFSI gel polymer electrolyte could be a promising electrolyte candidate for electrochemical device applications. [ABSTRACT FROM AUTHOR]