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Cadmium uptake reduction in paddy rice with a combination of water management, soil application of calcium magnesium phosphate and foliar spraying of Si/Se 全文
2021
Cai, Yanming | Wang, Xiaomeng | Beesley, Luke | Zhang, Zulin | Zhi, Suli | Ding, Yongzhen
A field experiment with 24 different treatments was carried out to study the effects of a combination of water management (WM), soil application of calcium magnesium phosphate (CMP), and foliar spraying of Si/Se on Cd uptake by paddy rice (Teyou 524). The water management modes included W₁ (conventional water management) and W₂ (flooding during the whole growth period). The application of CMP included P₁ (1800 kg·hm⁻²) and P₂ (3000 kg·hm⁻²). The leaf spraying regulations included LS (2.0 mmol·L⁻¹ Na₂SiO₃), LX (25 μmol·L⁻¹ Na₂SeO₃), and LSX (1.0 mmol·L⁻¹ Na₂SiO₃ and 12.5 μmol·L⁻¹ Na₂SeO₃). The results indicated that, compared to the control (W₁), flooding and CMP reduced soil exchangeable Cd by 10.3, 21.5, 32.2, 27.6 and 36.9% under conditions of W₂, P₁, P₂, W₂P₁ and W₂P₂, respectively; but the grain yield was reduced under W₂ condition. Some individual treatments, including W₂, P₁, P₂, LS, LX, and LSX, could reduce Cd concentration in the grain by 23.1–60.3%; but the combined regulations could reduce grain Cd concentrations up to 79.5%. Only the combined mode of CMP and leaf spraying of Si/Se could control grain Cd concentration below the Chinese National Food Safety Standard (0.2 mg·kg⁻¹). Combined modes of fertilizer application (W₂ and CMP) and foliar spraying (Si/Se), including W₂P₂LS, W₂P₂LX, W₂P₂LSX, were the most effective in reducing the Cd transport coefficients of both root-to-straw (RS) and straw-to-seed (SS). Considering Cd concentration in grain, treatments W₂P₂LS and W₂P₂LSX were the most effective ones, which could reduce Cd concentrations to 0.090 mg·kg⁻¹ and 0.089 mg·kg⁻¹ in grain, respectively. These results demonstrated that combined manipulation of the root zone (W₂ and CMP) and foliar spraying (Si/Se) can effectively reduce grain Cd concentrations in rice.
显示更多 [+] 显示较少 [-]The evolution characteristics and influence factors of carbon productivity in China’s industrial sector: from the perspective of embodied carbon emissions 全文
2021
Guo, Feng | Meng, Siqi | Sun, Renjin
In the context of low-carbon economic development, carbon productivity has effectively integrated the two major objectives of carbon reduction and economic growth, and increasing carbon productivity has become the main approach to address global climate change. Using data from China’s input–output table for 2002–2017, this study measures the evolutionary characteristics and influencing factors of carbon productivity from the perspective of embodied carbon emission in China’s industrial sector. The results indicate that, first, China’s industrial sectors’ carbon productivity shows an increasing trend from 25.22 to 65.3 million yuan/10,000 tons of CO₂ in 2002–2017, but the overall level is low. The energy efficiency factor is a major element affecting improvement in carbon productivity. Second, the carbon productivity of the 28 industrial sectors shows an increasing trend. There is a significant gap in the carbon productivity between different industrial sectors. The energy efficiency factor in all industrial sectors is positive, indicating that energy efficiency is a positive factor in increasing carbon productivity. Third, from largest to smallest in the carbon productivity are the primary, tertiary, and secondary industries. Finally, this paper recommends several approaches to improve carbon productivity from the perspectives of technology, differentiated policies of carbon emission reduction, and industrial structure adjustment.
显示更多 [+] 显示较少 [-]Electrophoretic banding patterns of protein induced by pinoxaden, tribenuron-methyl, and pyroxsulam herbicides in wheat leaves (Triticum aestivum L.) 全文
2021
Abdel-Wahab, Sarah I. Z. | Aioub, Ali A. A. | Salem, Rehab E. M. E. | El-Sobki, Ahmed E. A.
Herbicides are the most effective tool against weed flora in cereal crops that help to maintain and increase crop yields. This investigation was conducted in the winter season of 2018 to study the stress effect of three post-emergence herbicides including pinoxaden, tribenuron-methyl, and pyroxsulam on the biochemical changes at the molecular cell level of wheat. These herbicides were applied either lonely with a rate of 0.45 L.ha⁻¹, 22.5 gm.ha⁻¹, and 0.16 Ib a.i/A, respectively, or in combinations together on three Egyptian varieties of bread wheat known as Misr 1, Giza17 1, and Gemmiza 11. Firstly, the abovementioned herbicides were used at the recommended and half recommended doses with their combinations for these varieties to investigate DNA-protein linkage as a signal effect of herbicides at the molecular cell level.Our data showed that the treatment of wheat varieties with the tested herbicides induced new bands with low and high molecular weights of 37.49, 40.08, 146.55, and 147.23 KDa with relative mobility of 0.1574, 0.1603, 0.2166, and 0.2168, respectively. These bands were not presented in the control treatment, suggesting that it might be used as a biochemical marker for plant defense genes. Meanwhile, the control treatment exhibited only five or six bands in the three varieties. However, the tested varieties showed that the same number of bands, the molecular weights of bands, and their relative mobility were significantly varied between the single and the combinations treatment of herbicides. The best treatment was achieved by the combination between pinoxaden and tribenuron-methyl at a recommended dose which induced a large number of protein bands compared to the control treatment on the wheat variety cv. Misr 1, which gave one band with low molecular weight 71.44 KDa at Rf 0.1854 and other with the highest molecular weight 147.23 KDa at Rf 0.2168, compared to the control treatment.
显示更多 [+] 显示较少 [-]Zig-zag technology adoption behavior among brick kiln owners in Pakistan 全文
2021
Hussain, Bilal | Naqvi, Syed Asif Ali | Anwar, Sofia | Shah, Syed Ale Raza | Hassan, Rai Hasis ul | Shah, Ashfaq Ahmad
This study uses the theory of planned behavior to examine the individual’s intentions and zig-zag kiln technology adoption attitude in responding to carbon emissions in Pakistan. This study is based on cross-sectional data and a representative sample of 335 brick kilns owners from 11 districts of Punjab province of Pakistan is collected. Partial least squares structural equation modeling technique was used for the analysis. Results depicted that environmental concern and self-efficacy have a significant influence on attitude toward sustainable technology while subjective norms have a significant effect on intentions toward zig-zag kiln technology. A 1% increase in environmental concern and self-efficacy increases sustainable environmental technology by 24% and 58%, respectively. Furthermore, perceived behavioral control and intentions also significantly impact adoption attitude, and a 1% increase in perceived behavioral control and intentions increase the zig-zag kiln adoption attitude by 68% and 30%, respectively. Results depicted that adoption attitude is significantly determined by these explanatory variables. The study’s findings provided new evidence for the government to place more emphasis on enhancing kiln owners’ attitudes, social norms, and perceived behavioral control, which would lead towards the adoption of this new technique.
显示更多 [+] 显示较少 [-]Green standard model using machine learning: identifying threats and opportunities facing the implementation of green building in Iran 全文
2021
Rajabi, Mohamad | Sardroud, Javad Majrouhi | Kheyroddin, Ali
Residential buildings consume a major portion of energy resources and hence are seriously involved in environmental pollution. In Iran, fossil fuel consumption is growing, such that it increased by more than 400% from 1990 to 2018. One of the fundamental solutions for reducing fossil fuel consumption and creating a healthy environment inside and outside buildings is implementing and developing green buildings. This study seeks to examine the barriers to and opportunities for developing green buildings and proposes a localized green standard appropriate for the conditions of Iran. To this end, the required parameters were identified using the opinions of experts and the Delphi method. The opinions of 81 building experts, including the employers, consultants, and contractors, were obtained using a three-part questionnaire. Based on the results from the machine learning method, the score of the localized green building in five dimensions, namely, site, water, energy, materials, and quality of the indoor environment was calculated to be 77.2, while the energy dimension was determined to be the most important green standard dimension with a significance coefficient of 0.548. In the ranking analysis of all parameters using the Friedman test, the parameters of energy consumption management, renewable energy usage, and thermal zoning received the highest scores among other factors. Furthermore, a lack of awareness on green buildings (77%) and a high potential for renewable energy production (81%) were respectively identified as the biggest barrier to and opportunity for the implementation of green buildings in Iran.
显示更多 [+] 显示较少 [-]Exposure to BTEX concentration and the related health risk assessment in printing and copying centers 全文
2021
Rostami, Roohollah | Fazlzadeh, Mehdi | Babaei-Pouya, Amin | Abazari, Malek | Rastgho, Leila | Ghasemi, Roohollah | Saranjam, Behzad
This study was derived to investigation of BTEX (benzene, toluene, ethylbenzene, xylenes) concentrations in printing and copying centers (PCCs) in Ardabil city of Iran. Fifty-three PCCs were randomly selected from all the 136 number of PCCs and BTEX was sampled form their indoor air. The results showed that the concentration of BTEX in the indoor air PCCs is lower than the OELs (occupational exposure limit) in all cases. The obtained mean concentrations of benzene, toluene, ethylbenzene, and xylene were 93.6±63.2, 150.6±99.2, 34.3±16.8, and 29.5±15.2 μg/m³ respectively. Type of printer, number of printing and copying device, and type of ventilation system had significant influence on the BTEX concentration. The mean inhalation lifetime cancer risk (LTCR) value for benzene and ethylbenzene in the indoor air of the PCCs with LaserJet and inkjet printers was 44.4 × 10⁻⁶ and 153.3 × 10⁻⁶, and 23.4×10⁻⁶ and 54.2× 10⁻⁶, respectively, which were higher than EPA (Environmental Protection Agency) and World Health Organization (WHO) recommended limits. The hazard quotient (HQ) of benzene in the indoor air of the PCCs with inkjet printers was >1, which indicates that the non-carcinogenic risks associated with exposure to these compounds are considerable.
显示更多 [+] 显示较少 [-]Immobilization of heavy metal(loid)s in acid paddy soil by soil replacement-biochar amendment technology under normal wet condition 全文
2021
Jiang, Shaojun | Duan, Lianxin | Dai, Guangling | Shu, Yuehong
The remediation of agricultural soil contaminated by acid mine drainages (AMD) with extreme acidity and elevated concentrations of metal(loid)s still remains to be solved. In the present study, the combination of soil replacement-biochar (BC) amendment was adopted in 270-day incubation experiments to evaluate the effect on the metal(loids) (As, Pb, Cu, Cd, and Zn) immobilization and soil properties (pH, dissolved organic carbon (DOC), redox potential (Eh), and soil water holding capacity (SWC)). The incubation study showed that soil replacement-biochar amendment improved soil health by changing soil properties, which in turn exhibited significant effects on CaCl₂-extracted metal(loid)s. The combination of soil replacement and biochar amendment exhibited positive effect on the immobilization of Pb, Cu, Cd, and Zn, while, the risk of As and Cd mobility induced by biochar in the ageing process should be paid attention. Further laboratory seed germination study suggested that soil replacement-biochar amendment could effectively alleviate the stress of metal(loid)s, with the treatment of S50BC achieving the best remediation results. The results of this study suggested that soil replacement-biochar amendment was a promising remediation technology for agricultural soil contaminated by AMD. Graphical abstract
显示更多 [+] 显示较少 [-]The spatial network and its driving factors for sustainable total-factor ecology efficiency: the case of China 全文
2021
Shen, Yongchang | Sun, Xiaoling | Fu, Yunyun
The interaction of regional ecological efficiency is important for promoting ecological efficiency. Using a gravity model and social network analysis, this study investigated the spatial network characteristics of the sustainable total-factor ecology efficiency (STFEcE) in 30 provinces of China from 2005 to 2016 for the first time. The quadratic assignment procedure (QAP) was also used to analyze the factors affecting the network. The results are as follows. (1) The STFEcE between regions exhibited a spatial network relationship. (2) Jiangsu, Guangdong, Shandong, Ningxia, and other provinces were in the center of the network, whereas Guangxi, Anhui, and other provinces were on the edge. (3) The 30 provinces were divided into four plates, and the connections in the network were primarily based on the relationship between plates. (4) The difference between urban population, energy structure, and technical advancement negatively impacted the network relationship. The provinces should fully understand the value of the STFEcE network and implement appropriate measures to achieve collaborative improvement of regional ecological efficiency according to their roles in the network.
显示更多 [+] 显示较少 [-]Synthesis and characterization of CuxO/Bi2O3 oxides for removal of HCHO under visible light irradiation 全文
2021
Lin, Zhihao | Meng, Mianwu | Ding, Hua | Zhang, Qi | Duan, Chaomin | Chen, Chaoshu | Huang, Siyu | Zhou, Zhenming
CuₓO/Bi₂O₃ oxides grown on nickel foam were synthesized via an electrodeposition method to degrade indoor HCHO under visible light irradiation and fully characterized by XRD, SEM, FT-IR, and UV-Vis technologies. The characterization results showed that the CuₓO/Bi₂O₃ oxides were successfully loaded on nickel foam and the visible light response spectrum was expanded to 740 nm. Plackett–Burman design combined with central composite design has been used to optimize factors that affect HCHO removal performance. The results demonstrated that bismuth nitrate content, polyethylene glycol 600 content, sintering time, and lactic acid concentration were the four most important factors affecting the HCHO removal performance over CuₓO/Bi₂O₃ sample. The optimum CuₓO/Bi₂O₃ sample could degrade 88.796% of HCHO in 300 min at the conditions of 4.28 mol/L lactic acid, 4.86% polyethylene glycol 600, 194.03 min sintering time, and 45.83 g bismuth nitrate, and the HCHO removal rate remained 82.3% after five cycles. A plausible mechanism for the degradation of HCHO under visible light irradiation was proposed. This work provides a feasible solution for removing indoor formaldehyde in the field of photocatalysis.
显示更多 [+] 显示较少 [-]Kinetics and Monte Carlo simulation of UV disinfection of B. subtilis spores and SARS-CoV-2 in dried saliva droplets 全文
2021
Gibson, John | Farnood, Ramin | Barbeau, Benoit
Surfaces can be contaminated by droplets produced through coughing or sneezing. In this exploratory work, the UV disinfection results of Bacillus subtilis spores in dried saliva droplets were fitted to a three-parameter kinetic model (R² ≥ 0.97). This model has a disinfection rate constant for single organisms and a smaller one for aggregates found in droplets. The fraction of organisms found in aggregates (β) could account for the effects of different-sized droplets in the experimental work. Since a wide spectrum of droplet sizes can be produced, and some of the rate constants were uncertain, Monte Carlo simulation was used to estimate the UV inactivation performance in dried saliva droplets in a variety of conditions. Using conservative distribution for β, the model was applied to the UV disinfection of SARS-CoV-2 in dried saliva droplets. It was shown that a one-log reduction of SARS-CoV-2 was very likely (p>99.9%) and a two-log reduction was probable (p=75%) at a dose of 60 mJ/cm². Aggregates tend to be variable and limit the log reductions that can be achieved at high UV doses.
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