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The effect of the combined application of nano-hydroxyapatite (NHAP) or nano-carbon black (NCB) on the phytoextraction of Pb by ryegrass was investigated as an enhanced remediation technique for soils by field-scale experiment. After the addition of 0.2% NHAP or NCB to the soil, temporal variation of the uptake of Pb in aboveground parts and roots were observed. Ryegrass shoot concentrations of Pb were lower with nano-materials application than without nano-materials for the first month. However, the shoot concentrations of Pb were significantly increased with nano-materials application, in particular NHAP groups. The ryegrass root concentrations of Pb were lower with nano-materials application for the first month. These results indicated that nano-materials had significant effects on stabilization of lead, especially at the beginning of the experiment. Along with the experimental proceeding, phytotoxicity was alleviated after the incorporation of nano-materials. The ryegrass biomass was significantly higher with nano-materials application. Consequently, the Pb phytoextraction potential of ryegrass significantly increased with nano-materials application compared to the gounps without nano-materials application. The total removal rates of soil Pb were higher after combined application of NHAP than NCB. NHAP is more suitable than NCB for in-situ remediation of Pb-contaminated soils. The ryegrass translocation factor exhibited a marked increase with time. It was thought that the major role of NHP and NBA might be to alleviate the Pb phytotoxicity and increase biomass of plants.

Crop cultivation in greenhouses under semi-arid climatic conditions is subject to various stresses, in particular during the winter season at night, when the interior air is poorly controlled, leading to prolonged periods of low temperature. The aim is then to evaluate and control the heat exchanges of the enclosure in order to prevent low indoor air temperatures and reduce the thermal load of the greenhouse. The objectives of this study are to investigate the convective and radiative heat exchanges at the cover in order to establish new correlations for the convective heat transfer coefficients in semi arid regions. The climatic parameters were measured inside and outside a closed empty glasshouse without crop, for three different nights during the winter season in the semi-arid land of Algeria. A physical model for analysing the convective heat transfers was implemented, and new correlations were established, parameterised, calibrated and validated thoroughly. A significant difference was observed between the correlations obtained by this study and the models obtained for other greenhouse designs under different climatic conditions. Results show that the convection mode along the inside wall of the cover is free turbulent. Conversely, the convection mode along the outside greenhouse cover remains forced turbulent. A consistent performance of the correlations was observed, both in the calibration and validation stages.

Abstract Egg yolk-derived P and N dual doped nano carbon capsules (PNCCs) have been synthesized and used as lithium ion battery anodes. The application of egg yolk as the carbon source is a new and environmental-friendly approach for biomass recycling. The reversible capacity of half cells made of PNCCs is as high as ~770 mA h g−1 at a current density of 0.5 A g−1 with considerable rate capacity and cycling stability. PNCCs show a capsule-like structure, which provide extra edges and active sites for lithium intercalation. The heteroatom doping also introduce defects and disorder, which increases the electrochemical activity and creates more active sites for lithium insertion.

This study aims to introduce, conceptualize, and design a novel biomass/gasification-driven hybrid energy configuration. The proposed hybrid configuration has four subsystems: reformer solid oxide fuel cell (RSOFC), biomass/gasification, homogeneous charge compression ignition engine (HCCIE) plus waste heat recovery system (WHRS). RSOFC and HCCIE systems are embedded to generate electric energy. The syngas required for these two subsystems is captured from the biomass/gasification subsystem. In addition to generating electrical energy, fuel cell is responsible for providing combustible fuel to the HCCIE subsystem. The embedded engine in the system can improve the proposed configuration efficiency by increasing the rate of electrical energy production. In addition, the dissipated heat of fuel cell and engine subsystems is recovered by WHRS. The proposed energy configuration is evaluated and discussed from energetically, exergetically and exergoeconomic and environmental aspects to obtain a comprehensive feasibility study of the plant. The offered hybrid design has new component's structure and relationships that have not been reported in the publications. The analysis indicated that the proposed hybrid configuration is capable of generating approximately 1100 kW and 366.3 W of electric and thermal power, respectively, with the overall energetic and exergetic efficiencies of 69.4% and 52.1%. Exergoeconomic analysis results revealed that the specific fuel cost of the total proposed configuration was approximately 1.96 USD per GJ. In addition, compared to a coal and petroleum oil-based power generation plants, the proposed hybrid configuration can have approximately 2.75-fold and 97.7% lower CO2 emissions, sequentially. Besides, the proposed system can rival other similar biomass-driven designs.

Ni3Mo3C was prepared by a modified organic colloid method and explored as anode catalyst for high-performance microbial fuel cell (MFC) based on Klebsiella pneumoniae (K. pneumoniae). The prepared sample was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET). The activity of the sample as anode catalyst for MFC based on K. pneumoniae was investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and polarization curve measurement. The results show that the adding of nickel in Mo2C increases the BET surface area of Mo2C and improves the electrocatalytic activity of Mo2C towards the oxidation of microbial fermentation products. The power density of MFC with 3 mg cm(-2) Ni3Mo3C anode is far higher than that of the MFC with carbon felt as anode without any catalyst, which is 19 % higher than that of Mo2C anode and produced 62 % as much as that of Pt anode, indicating that Ni3Mo3C is comparative to noble metal platinum as anode electrocatalyst for MFCs by increasing the loading.

Abstract Market-based instruments, particularly carbon tax, have recently drawn the attention of Chinese government by their cost-effective contribution to the achievement of China's climate targets. Most of the recent policy proposals have focused on its long-term impact. However, particularly for policy makers, both long term and short term effects of carbon tax would be necessary when determining tax rates. We provided a detailed analysis of short-term impacts of carbon tax on sectoral competitiveness in this paper. We divided China's economy into 36 sectors, based on its 2007 input–output table, in order to examine the ratio of carbon tax added costs to sector GDP. We were thus able to determine the impact level of a carbon tax on each sector. We then divided the sectoral trade impact into domestic competitiveness with regards to foreign imported products and international competitiveness external to the Chinese domestic market. We found that a high tax level (100 yuan/t CO2) may necessitate compensatory measures to certain highly affected industries, and that a low tax rate (10 yuan/t CO2) would generate few competitiveness problems for all industries and may therefore be considered as an appropriate starting point.

Moss-associated N2 fixation by epiphytic microbes is a key biogeochemical process in nutrient-limited high-latitude ecosystems. Abiotic drivers, such as temperature and moisture, and the identity of host mosses are critical sources of variation in N2 fixation rates. An understanding of the potential interaction between these factors is essential for predicting N inputs as moss communities change with the climate. To further understand the drivers and results of N2 fixation rate variation, we obtained natural abundance values of C and N isotopes and an associated rate of N2 fixation with 15N2 gas incubations in 34 moss species collected in three regions across Alaska, USA. We hypothesized that δ15N values would increase toward 0‰ with higher N2 fixation to reflect the increasing contribution of fixed N2 in moss biomass. Second, we hypothesized that δ13C and N2 fixation would be positively related, as enriched δ13C signatures reflect abiotic conditions favorable to N2 fixation. We expected that the magnitude of these relationships would vary among types of host mosses, reflecting differences in anatomy and habitat. We found little support for our first hypothesis, with only a modest positive relationship between N2 fixation rates and δ15N in a structural equation model. We found a significant positive relationship between δ13C and N2 fixation only in Hypnales, where the probability of N2 fixation activity reached 95% when δ13C values exceeded - 30.4‰. We conclude that moisture and temperature interact strongly with host moss identity in determining the extent to which abiotic conditions impact associated N2 fixation rates.

This study examined the effects of climate change on rice production in 30 Chinese provinces spanning 1998–2017. The study used the pooled mean group technique to capture the long-run and short-run effects of changing climatic conditions on rice production. It further employed the Dumitrescu–Hurlin panel causality test to examine the path of causality between the key variables and rice production. The study found that, in the long run, average temperature negatively influenced rice production, but average rainfall had a positive effect on rice production. The results indicated that the cultivated area and fertilizer usage were positively related to rice production in the long run. The short-run results accentuated that average temperature favourably influenced nationwide rice production, whereas average rainfall had no substantial effect on national rice production. The cultivated area had a significant positive short-term relationship with rice production, although the impact of fertilizer usage on rice production was negligible in the short run. Besides, the results established a bidirectional causality between rice output and the cultivated area, but there was a one-way causality running from fertilizer usage to rice output. Finally, the results indicated that, except for rainfall, a unidirectional causality exists between temperature and rice production. The study, therefore, recommends that in the case of crop failure due to weather conditions, policymakers could implement a new pricing policy to mitigate the deterioration of the farmers’ income. The government must also develop and implement an insurance scheme that compensates farmers for catastrophes induced by rainfall deficiency.