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Haze has become an important topic for discussion in relation to global atmospheric pollution prevention and control due to its environmental and health effects. In order to explore the change in the space-time pattern of haze in the Yangtze River Delta of China and the associated human health losses, this paper uses MODIS Level 2 aerosol products of 2000-14 as well as applying the Kriging interpolation method to analyze the characteristics of changes of aerosol optical depth (AOD). The human capital method is then applied to evaluate the health losses caused by haze pollution in 2004-13. The research proves that in the latest 15 years, the AOD in the Yangtze River Delta has fluctuately risen from 0.5645 in 2000 to 0.5841 in 2014, with the spatial distribution pattern higher in the north and lower in the south. The northern cities of Shanghai, the southern part of Jiangsu Province, and the Hangzhou Bay region have always registered highest values. This analysis also shows that elevated concentration has gradually spread toward the southern areas. Meanwhile, the health losses in the whole region and each city have tended to be aggravated; the health losses in southern cities are far lower than those in northern cities. For example, the southern cities of Zhoushan and Taizhou see the lowest health losses ($0.039 billion and $0.035 billion, respectively). Conversely, the highest health losses are located in the northern cities of Shanghai, at $13.60 billion. However, the growth rate of health losses in southern cities is obviously higher than that in northern cities as a result of pollution transfer at the average rates of 249.18% and 99.94%.
With the rapid development of photovoltaic power generation technology, photovoltaic power generation system has gradually become an important component of the integrated energy system of marine. High precision short-term photovoltaic power generation forecasting is becoming one of the key technologies in ship energy saving and ship energy efficiency improving. Aiming at the characteristics of marine photovoltaic power generation system, we designed a highprecision power forecasting model (WT+ESN) for marine photovoltaic power generation system with anti-marine environmental interference. In this model, the information mining of the photovoltaic system in marine environment is carried out based on wavelet theory, then the forecasting model basing on echo state network is construct ed. Lastly, three kinds of error metrics are compared with the three traditional models by Matlab, the result shows that the model has high forecasting accuracy and strong robustness to marine environmental factors, which is of great significance to save fuel for ships, improve the energy utilization rate and assist the power dispatching and fuel dispatching of the marine power generation system
This paper attempts to give a microeconomic explanation of the environmental Kuznets curve (EKC) hypothesis according to marginal cost and marginal revenue. The interpretation about the shape and inflection point of EKC is based on the comparison between marginal cost and marginal revenue. The emissions of carbon dioxide (CO₂), nitrous oxide (N₂O) and methane are used as the environmental indicators and GDP per person is used as the economic indicator. Through the analysis of U.S. data from 1960 to 2010, we investigated the EKC hypothesis using the co-integration and correlation methods. The curve of CO₂ versus GDP per person in the U.S. is a wave shape in a different time scale. The relationship between N₂O and GDP per person showed the same trend with CO₂. The EKC curve between the methane and the GDP per person from 1990 to 2009 is a U-shape. Thus, we analyzed the relationship according to the microeconomic explanation of the EKC.
In order to accurately estimate soil organic carbon storage (SOCS), 2,755 soil profiles and 23,536 soil samples were acquired by grid method, followed by a study on the SOCS, soil bulk density (SBD), gravel content (GC), and distribution characteristics of rock coverage (RC) in a small karst watershed (SKC). Then on the basis of soil profile summation, an investigation was done on the applicability of RC/GC-based soil type method, land utilization type method, and aspect method to the estimation of SOCS in SKC at different depths. As shown by the results, the average soil organic carbon content (SOC) in the soil samples ranged from 5.25 to 24.87 g.kg⁻¹, and decreased with the soil depth increasing; the average SBD ranged from 1.17 to 1.41 g.cm⁻³, which first increased with the soil depth increasing and then tended to be steady; the average GC ranged from 0 to 20.15%, which decreased gradually with the soil depth increasing and finally to zero; the RC ranged from 0 to 86.32% at different sample points. RC and GC greatly affected the estimation of SOCS, so after correction based on RC and GC, the soil type method was adopted for estimation, concluding that SOCS at depths of 0-20 cm, 0-30 cm, and 0-100 cm was 341.82×10⁶ kg, 449.29×10⁶ kg, and 738.351×06 kg, respectively; RC and GC affected white sandy soil the most, as shown by the following SOCS estimated by the land utilization type method: 319.56×10⁶ kg, 416.04×10⁶ kg, and 607.02×10⁶ kg, respectively, at depths of 0-20 cm, 0-30 cm, and 0-100 cm; RC and GC affected wasteland the most, as shown by the following SOCS estimated by the aspect method: 318.64×10⁶ kg, 411.63×10⁶ kg, and 628.46×10⁶ kg, respectively, at depths of 0-20 cm, 0-30 cm, and 0-100 cm; RC and GC affected the SOCS in the south slope the most; in terms of catchment scale, the “vertical stratification + horizontal classification” pattern was expanded to the “land utilization type method” and “aspect method.” For estimating the SOCS in topsoil, the aspect method achieved the best result, while the land utilization type method achieved the best result at a depth of 100 cm.
In this paper, we report on abundant fossils of Platybelodon from the Middle Miocene of the Linxia Basin, China. Most of the fossils were discovered at two localities (Laogou and Zengjia) in the upper Middle Miocene Hujialiang Formation, and possess derived characters for the genus, including a relatively slender upper incisor, the development of a transverse ledge on the narrowest part of the mandibular symphysis, narrow, elongate and hypsodont third molars, the development of fourth loph(id)s on the second molars, and the development of small enamel conules and cementum in the interloph(id)s. Following comparisons with other Eurasian platybelodonts, we assign these remains to Platybelodon grangeri, and demonstrate that they are morphologically intermediate between P. grangeri from the Tunggurian localities of Tarim Nor and Platybelodon Quarry in Inner Mongolia. We suggest that the locality of Laogou may be younger than that of Zengjia, based on the occurrence of platybelodonts showing a suite of more derived characters. In addition, we assign two further specimens of Platybelodon from the lower Middle Miocene Dongxiang Formation of the Linxia Basin to Platybelodon danovi, owing to their retention of plesiomorphic characters distinguishing them from other Linxia Platybelodon fossils. Based on a cladistic analysis, we propose an evolutionary sequence of platybelodonts in Eurasia, and discuss potential functional adaptations.
Tartary buckwheat (Fagopyrum tataricum) seeds were irradiated with microwaves at various power levels of 200, 400, 600 and 800 W for 10 or 30 s. The irradiated grains were germinated for 3, 5, and 7 days and harvested. The germination rate of the tartary buckwheat seeds and contents of some compounds in the sprouts were investigated. The results showed that the exposure to 600 W microwaves for 10 s resulted in the highest fi nal germination rate after 7 days of germination, which was 2 times that of the control. The exposure of seeds to 800 W for 30 s showed the lowest germination rate (approximately 10%), which decreased by 87% compared with the control (p<0.05). The exposure at 600 W for 30 s stimulated the total flavones content, reduced the sugar and soluble protein contents, and increased the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The highest free amino acid content (11 mg/g) was observed in 5-day sprouts exposed to 800 W for 10 s. Moreover, the microwave treatment had a positive effect on the catalase (CAT) and superoxide dismutase (SOD) activity.
This study analyzes the effects of cold air on catecholamine (CA) levels. The CA levels of patients with cardio-cerebrovascular diseases, healthy people, Wistar rats, and spontaneously hypertensive (SHR) rats were determined before, during, and after cold air activity. The levels of dopamine (DA), norepinephrine (NE), and adrenaline (AD in humans and experimental animals changed in all three periods of cold air activity. The change in DA levels was statistically significant (P<0.05). The DA, NE, and AD levels in the controls and the Wistar rats increased during cold air activity and decreased after cold air activity. The variation in CA levels was not exactly the same between the SHR rats and the cardio-cerebrovascular disease patients. The special meteorological conditions caused by cold air affects CA secretion, which induces the occurrence, development, and outcome of cardio-cerebrovascular diseases. Moreover, the results of the animal experiments could not be directly extrapolated to humans.
A 3-D thermal discharge numerical model based on the Navier-Stokes equation, the k–ε turbulence model, and the temperature diffusion-controlled equation was developed to simulate the 3-D distribution of thermal discharge along a river-type reservoir under different discharge conditions, hydrological conditions and reservoir water levels. Results showed that the thermal discharge from the power plant would have a smaller effect on a deep-water reservoir. Neither 1ºC, 2ºC nor 3ºC isotherm appear in any scenario conditions. For dam water depths of 155 m and 175 m, a small envelope area of 0.05ºC isothermal line was predicted. The isothermal lines of 0.05ºC and 0.1ºC covered a small area in all scenario conditions. The temperature increase 500 m downstream of the discharge point was predicted to be less than 0.05ºC during dry seasons. The predicted stability time of the temperature increase in each layer was 20 days. It evidences the thermal impact intensity and the extent is different under three scenario conditions. The predicted space–time distribution of the cooling water and the temperature increase provide scientific bases for designing water intake and water management. In the future, the influence of thermal discharge on water quality and aquatic organisms of the reservoir will be discussed based on the simulation results of this study, that is, the variation law of water temperature caused by thermal discharge.
Focusing on the influence of wind and surface currents on local path planning in the marine environment, a multi-layered potential field (MPF) method is proposed to minimize the energy consumption of a water-jet propelled unmanned surface vehicle (USV). A synthetic environment framework that can incorporate the information of the base potential field layer and the environment layer is constructed first. This framework provides a base for minimizing the energy consumption of the water-jet propelled USV through proper force weighting. For the purpose of USV path planning, the traditional potential field method is extended by including the velocity information of the USV and the approached obstacles to avoid collisions with dynamic obstacles. The proposed method integrates kinematic control to prevent considering the vehicle as a point mass or rigid body. Finally, simulation and comparison experiments are performed to demonstrate the energy-saving efficiency of the proposed local path planning approach for the water-jet propelled USV
The anti-impact ability of shafting affects stability and security of the ship power transmission directly. Moreover, it also cannot be ignored that the rub-impact loads have influence on the torsion vibration of ship shafting. In order to solve the problem of engineering application of reliability assessment under rub-impact loads, a test rig with rubbing generator is established. By carrying out the integrative analysis, the torsional vibration characteristics, such as vibration amplitude and orbit of axle center under the rub impact load are studied. According to the rub-impact conditions obtained through numerical simulation, the experimental verification is carried out on the test rig with rubbing generator. The results show that it is not obvious the influence of rub-impact loads upon the shafting torsion vibration except in special working conditions, that can be simulated by the rubbing generator. The maximum amplitude of torsional vibration is influenced by the radial rigidity as well as the friction coefficient of rubbing body, and the degree of influence is difference under conditions of continuous rubbing and serious rubbing. By adjusting the rigidity of stern bearing, the influence of rub-impact upon shafting can be weaken, which provides a theoretical reference for the safety evaluation of ship shafting
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Brain endocasts are rare in the fossil record because they are only preserved under exceptional conditions. An equid brain endocast from the early Pleistocene of Wanrong County, Shanxi Province, China, is reported in this paper. Measuring approximately 140 × 95.2 × 83 mm, the new specimen represents a relatively advanced adult horse brain. Comparisons indicate that it is more derived than those of Hyracotherium and Mesohippus in having an expanded neocortex, and more than those of Pliohippus and Hipparion in having an enlarged network of branching sulci; in most characters involving these sulci, the Shanxi brain conforms to the extant species Equus caballus. The sulcus diagonalis of the Equus brain appears to have evolved conservatively during the early Pleistocene, whereas the sulcus suprasylvius seems to have evolved rapidly. The specimen demonstrates that the development of a high degree of complexity predates the enlargement of the brain in the horse, which increased in length, breadth, and especially height during the late Cenozoic.
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