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2.
Huan Jing Ke Xue ; 43(11): 5294-5304, 2022 Nov 08.
Article in Chinese | MEDLINE | ID: mdl-36437101

ABSTRACT

The top 23 countries with energy consumption accounting for 80% of the worldwide total in 2020 were selected as the research objects for this study. The energy consumption structure of these countries has been compared and studied from the proportion of clean energy in primary energy, the clean utilization rate of fossil energy, and the proportion of electric energy in terminal energy consumption, and the characteristics of energy consumption intensity were also analyzed based on the energy consumption per unit GDP, capital, and unit land area. The energy consumption patterns of various countries in social-economic operation, production, and life were also discussed, combined with the characteristics of industrial structure and subsector energy consumption. The concept of natural carbon sink load ratio of energy consumption was put forward, and the advantages and challenges of energy consumption mode transformation under carbon peak and carbon neutralization goals in China were identified and analyzed. The results showed that:the proportion of clean energy in primary energy, the proportion of energy consumption for power generation, the clean utilization rate of fossil energy, and the proportion of electric energy in terminal energy consumption in China were 15.90%, 53.48%, 37.51%, and 26.54%,respectively,all of which were in the forefront among the major energy-consuming countries in the world. China has built a favorable structural foundation for energy-intensive and clean utilization and formed a green and low-carbon energy consumption model; the proportion of non-industrial and agricultural energy consumption, especially that of transportation energy consumption, were both the lowest among major energy-consuming countries, and there is still much room for improvement in overall energy productivity based on the optimization of industrial structure. However, the relatively short carbon peak and neutralization target period poses a great challenge to the development speed and scale of clean energy to China, and the international situation under the constraint of carbon emission also increases the difficulty for China to achieve the carbon reduction goal by optimizing and adjusting the industrial structure.


Subject(s)
Carbon , Industry , Carbon/analysis , Carbon Dioxide/analysis , Electricity , China
3.
Int J Biol Macromol ; 157: 641-647, 2020 Aug 15.
Article in English | MEDLINE | ID: mdl-31786299

ABSTRACT

The objective of this work was to fabricate and characterize food-grade pea protein isolate (PPI) and carbohydrate polymer pullulan (PUL) nanofiber films by using green electrospinning technology. The effect of the blend ratios on the PPI/PUL solution properties (e.g. viscosity, surface tension and electrical conductivity) and morphology of the resulting electrospun nanofibers was investigated. The presence of PUL in the blends resulted in decreased apparent viscosity (P < 0.05), stable surface tension (42.09-46.26 mN/m) (P < 0.05) and lower conductivity of the solutions (P < 0.05), which were due to a better chain entanglement and decrease in the polyelectrolyte protein character, respectively, both factors were needed for uniform nanofiber (around 203 nm) formation. Rheological evaluation indicated a pseudoplastic behavior for all formulations. The Fourier transform infrared spectral changes and XRD patterns indicated that the protein and polysaccharide were well tangled in nanofibers. The results of the differential scanning calorimetry (DSC) indicate that thermal stability of the electrospun nanofiber films were improved in comparison to pure PUL. Finally, in order to expand the application range of the electrospun nanofiber films in future, thermal crosslinking method was conducted and water contact angles (WCAs) of the thermal treated nanofiber films exhibited better hydrophobic properties compared to the un-crosslinking samples.


Subject(s)
Glucans/chemistry , Nanofibers/chemistry , Pea Proteins/chemistry , Calorimetry, Differential Scanning , Glucans/isolation & purification , Hydrophobic and Hydrophilic Interactions , Pea Proteins/isolation & purification , Spectroscopy, Fourier Transform Infrared , Surface Tension
4.
Huan Jing Ke Xue ; 40(10): 4725-4732, 2019 Oct 08.
Article in Chinese | MEDLINE | ID: mdl-31854844

ABSTRACT

An eddy-covariance system combined with a semi-mechanistic model was used to analyze variations in gross primary productivity (GPP) and to simulate the impact of ozone (O3) on GPP under different levels O3 concentrations over a winter wheat field in Nanjing. The results showed that GPP was higher during the middle of the growth period and low during the early and late growth periods, reaching a maximum of 40 µmol·(m2·s)-1. Using high and low ozone sensitivity settings,O3-damage in 150, 100, 50 nL·L-1 and control treatment (CK) reduced GPP by -72%, -36%, -6%, and -10%, and by -13%, -6%, -1%, and -2%, respectively. These results provide a scientific basis for formulating defense strategies for O3 damage to crops.


Subject(s)
Ozone , Triticum , Crops, Agricultural , Seasons , Triticum/physiology
5.
Huan Jing Ke Xue ; 38(12): 5315-5325, 2017 Dec 08.
Article in Chinese | MEDLINE | ID: mdl-29964596

ABSTRACT

Surface ozone pollution and its negative effects on crops and food safety have attracted the attention of many people. In this study, ozone concentration and meteorological parameters in a winter wheat field were measured from 2014 to 2016. We analyzed the variations in ozone concentration and AOT40 during the growing season for winter wheat. According to the revised stomatal model, the leaf stomatal conductance of winter wheat was simulated and verified by comparing with measured results. Based on the flux model, the leaf stomatal fluxes of winter wheat were calculated. In addition, we estimated the effects of ozone concentration on winter wheat dry matter and yield by using exposure-response relationships and flux-response relationships. The results suggested that the concentration of ozone gradually increased during the growing season for winter wheat and showed a distinct unimodal pattern of diurnal variation. The mean concentrations of ozone were 36.2, 37.7, and 33.6 nL·L-1, respectively, and the ozone AOT40 values were 17.08, 17.90, and 11.84 µL·(L·h)-1, respectively, during the growing seasons for winter wheat from 2014 to 2016. The Jarvis-type factorial model of stomatal conductance could be used to simulate the stomatal conductance of winter wheat in the region, and approximately 81% of the variation of measured stomatal conductance could be accounted for by the model. The leaf stomatal ozone fluxes of winter wheat were 9.36, 9.32, and 8.65 mmol·m-2, respectively, from 2014 to 2016. Winter wheat yield decreased about 18.03%, and its dry matter decreased about 19.31% under ozone stress during these three years.


Subject(s)
Air Pollutants/analysis , Ozone/analysis , Triticum/growth & development , Plant Leaves
6.
Huan Jing Ke Xue ; 38(1): 412-422, 2017 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-29965074

ABSTRACT

As one of the main atmospheric pollutants over surface layer,researches on the increasing surface ozone concentration and its impact on main crops have become the focus of every government and the public.In this paper,based on the observations in Nanjing using the main local cultivars in China's major winter wheat producing areas,it was expected to obtain the data including ozone concentration,meteorological data and stomatal conductance by continuous observation.Stomatal conductance model was used and parameterized,combined with flux model,we analyzed the characteristics of stomatal flux in winter wheat under ozone pollution.At the same time,the stomatal conductance and stomatal ozone absorption flux of winter wheat were simulated in Jiangsu Province.The main results were as follows:Elevated ozone concentration could reduce stomatal conductance of winter wheat leaf and stomatal conductance decreased with the increase of ozone concentration.According to the observational data through the experiment,based on the boundary line technology,stomatal conductance model was parameterized to simulate stomatal conductance of wheat leaves from environmental factors.Approximately 90%,77% and 83% variation of measured stomatal conductance could be explained by the stomatal conductance model.In the experiment,the total ozone absorption flux in ozone concentration of CK (53.67 nL·L-1),100nL·L-1,150nL·L-1 was 6.42 mmol·m-2,12.27 mmol·m-2,13.90 mmol·m-2 respectively.The ozone concentration gradually increased from early period to late period during the period of winter wheat growth in Jiangsu area.The average stomatal conductance followed the order of the middle stage >the later stage >the early stage.Winter wheat ozone cumulative absorption flux was the highest during the middle stage.


Subject(s)
Air Pollutants/analysis , Ozone/analysis , Plant Leaves/physiology , Triticum/physiology , China , Spatio-Temporal Analysis
7.
Huan Jing Ke Xue ; 38(10): 4427-4437, 2017 Oct 08.
Article in Chinese | MEDLINE | ID: mdl-29965230

ABSTRACT

To better understand the ozone deposition and risk assessment over agroecosystems based on the ozone flux indices, an eddy-covariance system was used for measuring the ozone deposition continuously and dynamically in a winter wheat field. We analyzed the variations in ozone concentration, total ozone flux, and stomatal and non-stomatal flux. The relationships between stomatal/non-stomatal ozone deposition velocity and the main meteorological factors were investigated. Finally, the yield losses of winter wheat based on the ozone-dose index (AOT40) and ozone flux index (DFs06) were calculated. Results showed that average daily ozone concentration (cO3) was 32.9 nL·L-1. The daytime (08:00-18:00) and nighttime total ozone flux (FO3) were -7.6 nmol·(m2·s)-1 and -3.1 nmol·(m2·s)-1, respectively, and the mean diurnal FO3 was -5.1 nmol·(m2·s)-1. The mean daily stomatal ozone flux (Fs) and non-stomatal ozone flux (Fns) ranged from 0 to -5.1 nmol·(m2·s)-1 and from -1.43 to -10.31 nmol·(m2·s)-1, respectively. The mean diurnal Fs and Fns were -1.43 nmol·(m2·s)-1 and -3.66 nmol·(m2·s)-1. High solar radiation (SR), high temperature (T), and moderate humidity were used to analyze stomatal ozone deposition; high SR, moderate T, and high humidity were suitable to analyze non-stomatal ozone deposition. The cumulative total ozone flux (DFO3), cumulative stomatal ozone flux (DFs), and cumulative non-stomatal ozone flux (DFns) were 31.58, 9.99, and 21.59 mmol·m-2 during the entire experimental period, and DFs and DFns accounted for 32% and 68% of DFO3. The ranges of yield loss in winter wheat were estimated at 11.58%-20.37% and 20%-23.56% using different assessment models based on the ozone dose index AOT40 and ozone flux index DFs06, respectively.


Subject(s)
Air Pollutants/metabolism , Ozone/metabolism , Plant Stomata/metabolism , Triticum/metabolism , Environmental Monitoring , Risk Assessment
8.
Ying Yong Sheng Tai Xue Bao ; 27(10): 3196-3204, 2016 Oct.
Article in Chinese | MEDLINE | ID: mdl-29726145

ABSTRACT

In this study, the concentration of O3 and its deposition flux over a bare soil in Nanjing in autumn were observed by using an eddy covariance system with rapid ozone analyzer. We analyzed the correlation of ozone concentration, deposition flux, and meteorological conditions in order to explore the characteristics of the variations in ozone deposition flux and deposition velocity. We also compared flux and velocity by using modeled soil resistance with observations. The results showed that the diurnal variation of ozone concentration exhibited a single peak distribution, and it increased due to radiation enhancement from September 25th to October 28th, 2015. Ozone deposition flux over a bare soil in autumn was mainly affected by its concentration, with diurnal average values varying from -31.4 to -156.8 ng·s-1·m-2(the negative sign indicated that the deposition direction was toward the ground). As a result of non-vegetation over a bare soil, the ozone deposition flux was significantly influenced by environmental factors. Diurnal average of deposition velocities varied in the range of 0.09-0.30 cm·s-1. The turbulence exchange played a major role in the atmosphere transportation of ozone, and underlying surface condition was particularly important to O3 dry deposition over the bare soil. Soil resistance (Rs) increased exponentially with air relative humidity (RH), and the equation was Rs=89.981e0.0246RH. The parameterized ozone deposition velocities and fluxes were in good agreement with the measured values.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring , Ozone/analysis , Soil/chemistry , Atmosphere , Models, Theoretical
9.
Ying Yong Sheng Tai Xue Bao ; 27(6): 1811-1819, 2016 Jun.
Article in Chinese | MEDLINE | ID: mdl-29737687

ABSTRACT

Ozone is one of the main atmospheric pollutants over surface layer, and its increasing surface ozone concentration and its impact on main crops have become the focus of the public. In order to explore ozone deposition law and environmental factors influencing ozone deposition process, this study used the micrometeorological methods and carried out the experiment under natural conditions. The results showed that during the observational period (the vigorously growing season of wheat), the mean value of ozone flux was -0.35 µg·m-2·s-1(the negative sign indicated that the deposition direction was toward the ground). The mean rate of ozone deposition was 0.55 cm·s-1. The mean value of aerodynamic resistance was 30 s·m-1, the mean value of sub-layer resistance was 257 s·m-1, and that of the canopy layer stomatic resistance was 163 s·m-1. All the test parameters presented distinct diurnal fluctuation. The ozone deposition resistance was influenced by friction velocity, solar radiation velocity, temperature, relative humidity and other factors.


Subject(s)
Air Pollutants/analysis , Ozone/analysis , Triticum , Climate , Crops, Agricultural , Environmental Monitoring
10.
BMC Complement Altern Med ; 15: 315, 2015 Sep 07.
Article in English | MEDLINE | ID: mdl-26346982

ABSTRACT

BACKGROUND: Dysfunction of vascular endothelium is implicated in many pathological situations. Cytoskeleton plays an importance role in vascular endothelial permeability barrier and inflammatory response. Many Chinese herbs have the endothelial protective effect, of which, "Astragalus membranaceus" is a highly valued herb for treatment of cardiovascular and renal diseases in traditional Chinese medicine, In this study, we tested whether calycosin-7-O-ß-D-glucoside (Calycosin), a main effective monomer component of "Astragalus membranaceus", could protect endothelial cells from bacterial endotoxin (LPS)-induced cell injury. METHODS: Endothelial cell injury was induced by exposing human umbilical vein endothelial cells (HUVECs) to LPS. The effects of calycosin on LPS-induced changes in cell viability, apoptosis rate, cell migration, nitric oxide synthase (NOS), generationof intracellular reactive oxygen species (ROS) and cytoskeleton organization were determined. Microarray assay was employed to screen the possible gene expression change. Based on the results of microarray assay, the expression profile of genes involved in Rho/ROCK pathway and AKT pathway were further evaluated with quantitative real-time RT-PCR or western blot methods. RESULTS: Calycosin improved cell viability, suppressed apoptosis and protected the cells from LPS-induced reduction in cell migration and generation of ROS, protein level of NOS at a comparable magnitude to that of Y27632 and valsartan. Similar to Y27632 and valsartan, Calycosin, also neutralized LPS-induced actomyosin contraction and vinculin protein aggregation. Microarray assay, real-time PCR and western blot results revealed that LPS induced expression of FN, ITG A5, RhoA, PI3K (or PIP2 in western blotting), FAK, VEGF and VEGF R2, and inhibited expression of MLCP. We believed multiple pathways involved in the regulation of calycosin on HUVECs. Calycosin are considered to be able to activate MLCP through promoting the generation of NO, decreasing PMLC, suppressing the cytoskeleton remodeling caused by activation of Rho/ROCK pathway and inhibiting AKT pathway by decreasing VEGF, VEGF R2 and PI3K level. CONCLUSION: Calycosin protected HUVEC from LPS-induced endothelial injury, possibly through suppression of Rho/ROCK pathway and regulation of AKT pathway.


Subject(s)
Cytoskeleton/metabolism , Glucosides/metabolism , Isoflavones/metabolism , Oxidative Stress/physiology , Protein Serine-Threonine Kinases/metabolism , Signal Transduction/physiology , Cells, Cultured , Human Umbilical Vein Endothelial Cells , Humans
11.
Ying Yong Sheng Tai Xue Bao ; 22(6): 1457-64, 2011 Jun.
Article in Chinese | MEDLINE | ID: mdl-21941745

ABSTRACT

Taking winter wheat Triticum aestivum L. (cv. Yangmai 13) as test material, a field experiment was conducted in Nanjing City to study the effects of simulated reduced solar radiation on the diurnal variation of winter wheat flag leaf photosynthetic rate and the main affecting factors. Five treatments were installed, i. e., 15% (T15), 20% (T20) , 40% (T40), 60% (T60), and 100% (CK) of total incident solar radiation. Reduced solar irradiance increased the chlorophyll and lutein contents significantly, but decreased the net photosynthetic rate (Pn). Under different solar irradiance, the diurnal variation of Pn had greater difference, and the daily maximum Pn was in the order of CK > T60 > T40 > T 20 > T15. In CK, the Pn exhibited a double peak diurnal curve; while in the other four treatments, the Pn showed a single peak curve, and the peak was lagged behind that of CK. Correlation analysis showed that reduced solar irradiance was the main factor affecting the diurnal variation of Pn, but the physiological parameters also played important roles in determining the diurnal variation of Pn. In treatments T60 and T40, the photosynthesis active radiation (PAR), leaf temperature (T1) , stomatal conductance (Gs) , and transpiration rate (Tr) were significantly positively correlated with Pn, suggesting their positive effects on Pn. The intercellular CO2 concentration (Ci) and stomatal limitation (Ls) had significant negative correlations with Pn in treatments T60 and T40 but significant positive correlations with Pn in treatments T20 and T15, implying that the Ci and Ls had negative (or positive) effects on Pn when the solar irradiance was higher (or lower) than 40% of incident solar irradiance.


Subject(s)
Photosynthesis/physiology , Sunlight , Triticum/physiology , Computer Simulation , Ecosystem , Photosynthesis/radiation effects , Plant Leaves/physiology , Plant Leaves/radiation effects , Seasons , Triticum/radiation effects
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