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Accurate short-term power load forecasting is becoming more and more important for the stable operation and improved economic benefits of electric power systems. However, when affected by various factors the power load shows non-linear and non-stationary characteristics. In order to forecast power load precisely, we propose an extreme learning machine (ELM) combined with variational mode decomposition (VMD), as a new hybrid time series forecasting model. In the first stage, since decomposed modes and hidden layer nodes have great influence on prediction accuracy, a three-dimensional relationship has been established to determine them in advance. In the second stage, using VMD, the time series of power load is decomposed into predetermined modes that are then used to construct training parts and forecast outputs. Then every individual mode is taken as an input data to the ELM. Eventually, in the third stage, the final forecasted power load data is obtained by aggregating the forecasting results of all the modes. To testify the forecasting performance of the proposed model, a five-minute power load data in Hebei of China is used for simulation, and comprehensive evaluation criteria is proposed for quantitative error evaluation. Simulation results demonstrate that the proposed model performs better than some previous methods.
The issues of energy shortage and environmental pollution caused by energy subsidies are more serious in a massive energy-consuming country like China. Since the Group of 20 summit meeting on September 4, 2016, government leaders have confirmed that they will phase out inefficient fossil fuel subsidies. In this paper, we construct a computable general equilibrium model to analyze the impact of different de-subsidization policies based on possible reduction targets, mitigation routes, and reform periods. The results show that a nonlinear tendency in gross domestic product will emerge with the increasing intensity of de-subsidization targets. Moreover, there is a general macroeconomic recession both in output and consumption, where the prices have generally increased. The results also show that various mitigation routes of de-subsidization policy are slightly significant economically. However, the total removal of energy subsidy in one year will obtain an opposite conclusion with better social welfare and gross domestic product, but more carbon emissions and energy consumption. Overall, a medium target (50-90%) with an average reduction during 2010-2030 could be more suitable for China.
Cellulose-degrading strains play an important role in cellulose degradation at low temperatures. In this study, three cellulose-degrading strains with high carboxymethyl cellulase (CMCase) activity were isolated from the soil in a low temperature environment of 10ºC. ZS-7 was Cladosporium sp, ZS-8 was Alternaria porri, and ZS-10 was Trichoderma harzianum, based on 16s rDNA gene sequence analysis. They were mixed, marked as ZS-M, and used for corn straw degradation at 15ºC in order to determine their application properties. ZS-7, ZS-8, ZS-10, and ZS-M efficiently degraded corn straw by 45.98%, 47.96%, 34.215%, and 33.56%, respectively, after 30 days of stationary culture. The dynamics of CMC, β-Glucosidase, and FPA during corn straw degradation were determined. The CMCase activity of ZS-7 and ZS-8 was 31.732 U/ml and 31.111 U/ml, respectively, but the enzyme activities and degradation of ZS-M were lower than the single strain because of metabolic effects that influenced the degradation process. The pH values of ZS-7, ZS-10, and ZS-M were particularly stable, changing from 7.08 to 7.77 during the full degradation cycle. ZS-7, ZS-8, and ZS-10 could be applied more broadly to degrade corn straw in cold regions.
Bloom-Cyanobacteria can release phosphorus (P) into overlying water during their decline period, thus inevitably providing available P for the next round of bloom. In order to quantitatively evaluate the contribution of cyanobacterial bloom decline to P amounts in Caohai, a typical cyanobacteria-dominated sub-lake in northern Dianchi Lake, the P concentrations in algae during the peak and bottom of cyanobacterial bloom were measured and calculated. Remote sensing monitoring analysis and monthly monitoring data showed that the cyanobacterial bloom in Caohai developed from June, reached its peak in July to August and then declined to its bottom from December to February. The concentrations of different phosphorus forms contained in algal cells were different between the peak and bottom of the cyanobacterial bloom. Total phosphorus (TP) concentration in algae (TP-A) were higher in summer than in winter, while the TP content per unit Chl-a in winter was much larger than in summer. The annual released TP was approximately 24.12 tons in 2016, and its potential contribution to TP and Ortho-P in water body of Caohai was around 0.958 and 0.647 mg⋅L⁻¹, respectively. The P release amount was 303.30 and 20.57 tons in 2011 and 2014, respectively. For Caohai of Dianchi Lake, the P released from bloom-cyanobacteria could provide adequate P for the next year’s bloom recovery.
The effects of six emergent macrophytes (Typha orientalis, Acorus calamus, Oenanthe javanica, Scirpus validus, Sagittaria sagittifolia, and Pontederia cordata) on the growth of two strain Microcystis aeruginosa were studied under co-culture conditions. And the sensitivities of unicellular and colonial Microcystis strains to six emergent macrophytes were compared using an exudation experiment. Based on laboratory experiments, T. orientalis, A. calamus, O. javanica, S. validus, S. sagittifolia, and P. cordata had strong inhibitory effects on growth of unicellular M. aeruginosa, while only A. calamus and P. cordata show obvious growth inhibition on colonial M. aeruginosa. When the biomass density was 20 g FW·L⁻¹, the growth inhibition rate of unicellular M. aeruginosa can exceed 90% for all of the six emergent macrophytes. When macrophytes coexisted with the colonial M. aeruginosa, only A. calamus, P. cordata, and S. sagittifolia showed the growth inhibition of algae. Maximal inhibition of Chl a growth was 75% (p<0.05) for A. calamus, 69% (p<0.05) for P. cordata, and 40% for S. sagittifolia at 45 g FW·L⁻¹ on day 15. The results of the exudation experiment indicated that there were no significant differences between control and treatment of Chl a concentrations of colonial M. aeruginosa for all of the six macrophyte exudations on days 6 and 12. While after 6 d incubation in 100% and 50% macrophyte exudations (40 g FW·L⁻¹), the cell densities of unicellular M. aeruginosa in control were obviously higher than all those in treatment (p < 0.05). The maximal algal growth inhibition (89.62%) of unicellular M. aeruginosa was achieved in 100% exudation of A. calamus on day 6 (p < 0.05). So according to the results of exudation experiments, the unicellular M. aeruginosa was more sensitive than the colonial strain to six emergent macrophytes. And this different sensitivity between Microcystis species probably correlated positively with colony size.
The oofamily Dendroolithidae is a distinct group of dinosaur eggs reported from China and Mongolia, which is characterized by branched eggshell units and irregular pore canals. The ootaxonomic inferences, however, were rarely discussed until now. A colonial nesting site was recently uncovered from the Qinglongshan region, Yunxian, Hubei Province, China. More than 30 dendroolithid egg clutches outcrop on the Tumiaoling Hill, including an extremely gigantic clutch containing 77 eggs. All clutches were exposed in the Upper Cretaceous fluvial-deposited Gaogou For mation. In this study, we emend the diagnosis of the oogenus Placoolithus and assign all dendroolithid eggs from the Tumiaoling Hill to a newly emended oospecies Placoolithus tumiaolingensis that shows greatly variable eggshell microstructure. Moreover, our study also disentangles the previous vexing classification of dendroolithid eggs. We conclude that Dendroolithus tumiaolingensis, D. hongzhaiziensis, and Paradendroolithus qinglongshanensis, all of which were previously reported from Yunxian, should be assigned to the newly emended oospecies Placoolithus tumiaolingensis.
Two species of Kalicephalus Molin, 1861 were collected from the intestine of Varanus salvator (Laurenti, 1768) from Guangdong Wildlife Rescue Centre, Guangzhou, Guangdong Province, China. Kalicephalus (Kalicephalus) guangdongensis sp. nov. is similar to K. (K.) schadi Ogden, 1966 and K. (K.) schadi fotedari Kalia et Nayital, 1989 in having extremely long spicules, but differs from the latter in the relative length of spicules (spicules longer than the total body length instead of spicules almost three quarters of the total body length). Kalicephalus (Kalicephalus) schadi fotedari Kalia et Nayital, 1989 is reported for the first time in China, and Varanus salvator is a new host record.
Background. Though fishes grow indeterminately, very little is known of the effects of age on the morphometric indices (length, weight, and condition) in fishes as it is often difficult to cover the entire lifespan of a species in laboratory or nature. The presently reported study was thus conducted to elucidate the effects of age (and sex) on the growth indices using the annual fish and a laboratory model of aging. Materials and Methods. Experimental fish—the redtail notho, Nothobranchius guentheri (Pfeffer, 1893), were obtained by hatching the diapause eggs of the same parental lineage and reared over their entire lifespan. Length–weight measurements were recorded from 3–12 months and various indices (length–weight relation, Fulton’s condition factor, and relative condition factor) were computed and compared statistically. Results. Mean lengths, weights, length–weight relations (LWRs), Fulton’s condition factor (K) and relative condition factor (Kn) varied significantly leading to differential indices based on age and sex. Age influenced all indices positively, which is indicative of the indeterminate growth typical of fishes. Conclusion. Age was not seen to suppress the growth indices in the annual fish, which is suggestive of a healthy and delayed senescence in the annual fish N. guentheri. Whether other short- and long-lived finfish follow the same pattern needs further investigation.
In the Three Gorges Reservoir (TGR), sedimentation of the riparian zone has occurred over the past 10 years. However, the sediment and related environmental effects have not been explored well. In the present study, sediment and soil in situ were collected in three sites of the riparian zone in the TGR. Samples were analyzed for water content, bulk density, pH, organic matter, total nitrogen, total phosphorus, and heavy metals (As, Cr, Cu, Ni, Pb, Zn). Results revealed that, compared with soil, water content, organic matter, and total phosphorus of sediment were high while bulk density was low. Heavy metal concentrations (As, Cu, Pb, Zn) in sediment were significantly higher than those in soil. Sediment was moderately polluted by Cu and Pb, and soil was unpolluted-moderately polluted by As and Cu. Moreover, the individual and comprehensive potential ecological risk of heavy metals from both sediment and soil showed a low degree. Enrichment of nutrients and heavy metals in sediment of the riparian zone are probably of formation regime and anthropogenic activities, and could pose risks to the environment and human health. Therefore, enhanced efforts of soil and water conservation and pollution treatment in the upper stream of the Yangtze River and the TGR area should be recommended.
For this study we constructed an integrated evaluation model of water quantity and quality that couples the supply-demand balance system, water consumption balance system, and a simulation model of water quality. In order to realize the dual water supply, the constraint equation of dual water supply has been added in the supply-demand balance system. The water pollution-induced water shortage quantitative identification approach and the evaluation index of the proportion between social economic water consumption and ecological water use has been put forward to evaluate the satisfaction degree of ecological water use and water quality based on simulations of water quantity and quality. This study utilizes an application of the water quantity and quality evaluation model in the main stream of the Huangshui River (Qinghai, China). The evaluation results provide support for future water resource development and management as follows: (1) the water quality-index water shortage rate of the entire area was 3.7% and in some local areas reached 25.7% (2) the proportion of ecological water use of each water resource partition were all more than 80% (3) although the ecological water demand in the rivers could be satisfied, the standard-reaching rate of water quality was very low due to the total pollutants not having been controlled.
The Haloxylon ammodendron natural desert forest is an important vegetation formation and has a large distribution area in Junggar Basin, Xinjiang Province, China. In this paper, H. ammodendron populations were mapped, characterized and the spatial distribution patterns and spatial associations of H. ammodendron among different life stages (seedlings – S, juveniles – J, mature – M, overmature – O) were analyzed using O-ring univariate O11(r) and bivariate O12(r) statistics. We found that: (1) H. ammodendron was a regenerating population. (2) H. ammodendron (S), H. ammodendron (J), and H. ammodendron (M) showed significant aggregations at scale 0-8 m, 0-27 m, and 0-35 m, respectively, whereas H. ammodendron (O) tended to have random distributions at almost all scales. (3) The spatial associations between different life stages of H. ammodendron tended to turn from positive to negative if their size differences are enlarged increasingly. Strongly positive associations were found at small scales for only two pairs: H. ammodendron (S)-H. ammodendron (J), H. ammodendron (J)-H. ammodendron (M).
Arabidopsis noa1 mutant has a small stature and is more resistant to water deficit than wild-type Col-0. To investigate whether the size of noa1 plays a role in drought tolerance, Col-0, noa1 as well as gsnor1-3 and a transgenic line over-expressing a DnaJ domain Hsp40 from soybean (GmHSP40ox), all of which have smaller statures than Col-0, were subjected to drought treatment. Our results showed that the genotypes with smaller statures survived longer than Col-0 under drought conditions when grown in separate containers, which is correlated with the reduced net water losses of plants and the higher water content in the soil during the drought stress treatment. However, when randomly grown in the same containers, the plants of the four genotypes dried out almost at the same time, indicating that the reduced transpirations due to the smaller sizes of the mutant plants might account for the prolonged surviving under drought in separate containers. In the same-container experiment, the accelerated water loss caused by the transpiration of Col-0 plants most likely contributed to the earlier dry-out of the three genotypes with smaller statures because a certain amount of the transpired water through Col-0 could have been used by noa1 gsnor1-3 or GmHSP40ox if grown in separate pots. Interestingly, noa1 had less stomata densities and the stomatal closures of both noa1 and gsnor1-3 were more sensitive to ABA. In addition, noa1 was more resistant to osmotic stress than both Col-0 and gsnor1-3. To our surprise, the water loss rates of detached leaves of both noa1 and gsnor1-3 were greater than that of Col-0, suggesting that the water loss rates of detached leaves may not represent that of in planta leaves. Together, our results suggest that (1) plant sizes of different genotypes must be taken into consideration in evaluating drought trait, and multiple approaches and criteria are needed to ensure the accurate evaluation of drought tolerance; (2) when investigated genotypes have big differences in statures, both the samecontainer and the separate-container experiments are necessary for screening the resistant or tolerant genotypes; when the investigated genotypes have comparable statures, the separate-container experiment is more relevant; (3) the increased drought tolerance of noa1 is resulted from combined effects of the smaller stature, the increased sensitivity of stomata closure to ABA and the enhanced resistance to osmotic stress; and (4) water loss rate of detached leaves is not a good indicator in evaluating drought tolerance.
Falcaustra sinensis sp. nov. collected from the feces of Indotestudo elongata (Blyth) is described and illustrated. The new species can be distinguished from the congeners by the arrangement of caudal papillae of the male (6 pairs precloacal, 4 pairs postcloacal, 1 median), length of spicules (3.84–4.74 mm) and the presence of pseudosucker.
A total of 53 strains of chromium-resistant bacteria were isolated from Meiliang Bay of Taihu Lake, China and were tested for Cr(VI) resistance. The strain THKCS311 with the maximum growth value under Cr(VI) stress was regarded as the optimal strain for further study. The partial sequences were amplified from the strain and the BLAST query revealed that it was closely related to Bacillus sp., and it had 98% homologous to Bacillus mycoides strain 273 and Bacillus anthracis strain ATCC 14578. Batch experiments were conducted to remove Cr(VI) using THKCS311, and the effects of the initial Cr(VI) concentration, pH, and temperature condition on Cr(VI) removal efficiency were investigated. The results showed that Bacillus sp. can mediate reduction of Cr(VI)-Cr(III), and the removal efficiency decreased with the increase of initial Cr(VI) concentration. The removal efficiency of Cr(VI) was highest at pH 6.5 and 35ºC, and removal efficiencies were 59.2% and 60.7%, respectively. SEM micrographs indicated that THKCS311 cells were irregular and cracked with the appearance of wrinkles on the surface after Cr(VI) stress.
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