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For more efficient utilization of agricultural organic waste composts, this research formulates the demand of agricultural organic waste composts and the supply of compost converted from agricultural organic waste in the region, and models the demand-supply balance of agricultural organic waste compost in some regions. Objects of study include 6 urban districts, 5 county-level cities, and 21 counties in northern Henan Province, China. The crops’ latent demand for compost and the latent supply of compost converted from agricultural organic wastes (straw and livestock manure) in each region is computed for an analysis of demand-supply balance. According to the findings, there is a large deviation in both the ratio of the supply of livestock manure composts to that of straw composts and the demand-supply ratio of composts in the studied regions. To be specific, the overall demand-supply ratio in the studied regions is about 1.21, showing that demand is greater than supply. Theoretically, all agricultural organic wastes can be used for agricultural production in these regions. In addition, actual demand ratio (actual demand/ latent demand) is found in the utilization of composts. Supposing the actual demand ratio is 50%, research again analyzes the demand-supply balance, revealing that all livestock manure composts can be utilized, but that straw compost is surplus in large amounts in the studied regions.
Novel pollutant control equipment, which were called integrated pollutant control equipment, consisted of bag filters and activated carbon (AC) absorbers. The AC absorbers were put forward to absorb the additional pollutants between the old and new emission standards to satisfy Chinese emission standards. The absorbers could be fixed (mobile) bed, annular column, or fluidized bed. The numerical method was employed to simulate the inner flow fields in the integrated equipment. The results show that annular column absorbers can make the flow field more uniform than the others, but its absorption duration has to be discussed. The mobile bed and the annular column absorbers are recommended. The fluidized bed absorber can be applied only if strong heat and mass transfer during absorbtion are needed.
The hybrid structures show excellent performance on vibration reduction for ship, aircraft and spacecraft designs. Meanwhile, the topology optimization is widely used for structure vibration reduction and weight control. The design of hybrid structures considering simultaneous materials selection and topology optimization are big challenges in theoretical study and engineering applications. In this paper, according to the proposed laminate component method (LCM) and solid isotropic microstructure with penalty (SIMP) method, the mathematical formulations are presented for concurrent materials selection and topology optimizations of hybrid structures. Thickness distributions of the plies in laminate components are defined as materials selection design variables by LCM method. Relative densities of elements in the components are defined as topology design variables by SIMP method. Design examples of hybrid 3-bar truss structures and hybrid floating raft with vibration reduction requirements verified the effectiveness of the presented optimization models
A comprehensive analysis of normalized difference vegetation index (NDVI), land-use type, and digital elevation model (DEM) data by using the geographic information system (GIS) showed that the index had increased over time in 84 prefectures that were part of the Grain for Green Project. SPOT Vegetation (Satellite Pour l’Observation de la Terre Vegetation, or satellite observation of the earth’s vegetation) data and the NDVI showed that compared to 2000, in 2015 2.05% of the arable land in the study area was no longer cultivated and that 25% of the farmland with slopes steeper than 35° and 2.68% of the moderately sloped farmland (2-35°) had been turned into forests. The arable land had been converted mainly to woodland and grassland. The interpretation of thematic mapper (TM) images showed that forest cover had increased significantly (by nearly 22%); that vegetation cover was less than 10% over 95.27% of the area; and that the area with high vegetation cover had increased significantly. Superposition analysis of TM images and DEM data showed that the intensity of soil erosion had generally decreased, with the areas under mild and pole-strength soil erosion decreasing by more than 10%. However, the Grain for Green Project has failed to check severe soil erosion so far. At present, although 60% of the study area is covered by forests, the extent of change in the degree of vegetation cover varied over time, and the spatial distribution was uneven, being higher in the east than in the west. It is therefore important to continue to strengthen governance through such projects.
The main aim of this study was to describe the adsorption behaviours of acetaminophen (APAP) onto colloid and solid particle in sediment in terms of their impact on the factors of the processes (e.g., contact time, temperature, kinetic, thermodynamic characteristics) that were analyzed systematically. Sediment was collected from a typical tributary in the mid-Weihe River and a separation device was employed to separate sediment into colloid and solid particle. Results show that the adsorption of APAP onto colloid and solid particle reached equilibrium after about 12 hours and 48 hours, respectively. The adsorption capacity of APAP onto colloid was at least 28-fold larger than that onto solid particle with an initial APAP concentration of 10.0 mg·L⁻¹ at 25ºC. The Langmuir isotherm model was more suitable for describing the adsorption behaviours of APAP onto both colloid and solid particle in sediment. The adsorption processes were feasible, spontaneous, entropyincreasing, and endothermic in nature, the adsorption capacity increased with increasing temperature. The mechanisms controlling APAP adsorption onto colloid and solid particle were mainly physisorption, but physisorption less on APAP adsorption onto colloid. The obtained results provide a theoretical basis for the effective prevention of APAP pollution to the groundwater system in the Weihe River basin.
We applied decoupling relationship analysis in this study to explore the relationship between agricultural carbon emissions and agricultural economic growth using data from Hotan prefecture in 1999-2013. The results demonstrated: 1. During 1999-2013 the decoupling index between agricultural carbon emissions and agricultural economic growth showed a “decoupling, hooking, and decoupling” three-state process. This was in the relative decoupling stage between 1999 and 2004, the relative hook state between 2005 and 2009, and the relative decoupling stage between 2010 and 2013. According to the elastic index, the relationship was in a strong decoupling state between 2000 and 2002, a weak decoupling state between 2003 and 2004, an expansive negative decoupling state between 2005 and 2009, and a weak decoupling state between 2010 and 2013. 2. Hotan is an area whose carbon emissions intensity is higher than that of the China and Xinjiang regions, is a serious lag on the decoupling stage to the nation and the region, and cannot achieve its agricultural carbon emission reduction targets by 2030. Therefore, a low carbon agriculture economy is the best strategic choice to develop its economy and address global climate change in Hotan. Thus, we have proposed policy recommendations including the establishment of a low carbon sense, the change of agricultural development way, the development of agricultural S&T, and the establishment of an incentive mechanism.
The nuclear receptor RXRα (retinoid X receptor-α) is a transcription factor that regulates the expression of multiple genes. Its non-genomic function is largely related to its structure, polymeric forms and modification. Previous research revealed that some non-genomic activity of RXRα occurs via formation of heterodimers with Nur77. RXRα–Nur77 heterodimers translocate from the nucleus to the mitochondria in response to certain apoptotic stimuli and this activity correlates with cell apoptosis. More recent studies revealed a significant role for truncated RXRα (tRXRα), which interacts with the p85α subunit of the PI3K/AKT signaling pathway, leading to enhanced activation of AKT and promoting cell growth in vitro and in animals. We recently reported on a series of NSAID sulindac analogs that can bind to tRXRα through a unique binding mechanism. We also identified one analog, K-80003, which can inhibit cancer cell growth by inducing tRXRα to form a tetramer, thus disrupting p85α–tRXRα interaction. This review analyzes the non-genomic effects of RXRα in normal and tumor cells, and discusses the functional differences based on RXRα protein structure (structure source: the RCSB Protein Data Bank).
To assess the impact of human activity on the nitrogen (N) cycle and evaluate the sources of N in surface water, the N budget for Laoguanhe River Watershed (LRW), a typical agricultural watershed and one of the upstream tributaries of Danjiangkou Reservoir in China, was developed by using measurement data on N fluxes and literature data on other parameters. Over the whole watershed, fertilizers, human and livestock excreta, atmospheric deposition, biotic fixation, N from crop residue used as fertilizer, and imported animal feeds contributed 65.7%, 20.7%, 6.1%, 5.6%, 1.7%, and 0.3%, respectively, to total N input (40,816.6 kg N km⁻² year⁻¹). N transported to water bodies, denitrification, harvesting crops, and ammonia volatilization contributed 32.0%, 25.2%, 23.0%, and 19.8% of total N output (21291.2 kg N km⁻² year⁻¹), respectively. The N budget for the LRW suggested that more than 50% of the N input was lost to the environment, and about 17% was discharged as riverine N, which indicated that agricultural and human activities in the watershed substantially impacted water quality, and so altered the N biogeochemistry process.
Controlling carbon emissions without impairing urbanization and economic development highlights the necessity of researching energy-related carbon emissions. Urban areas have become the main source of energy consumption and carbon emissions. This paper has developed a modified version of the Kaya identity, which incorporates urbanization and resident consumption, to analyze urbanization effect on carbon emissions in Jiangsu Province. Then, the Kuznets curve theory was introduced to estimate the inflection point of the marginal urbanization effect. The results indicated that the urbanization effect was still an important factor that influences total carbon emissions. The marginal urbanization effect will still increase until the urbanization rate reaches 78.94%. Therefore, Jiangsu should also pay attention to the urbanization effect even though it may increase slowly or decrease, and the results of this paper on marginal urbanization effect make it clear that controlling the carbon emissions without the expense of urbanization growth and economic development is still a big challenge for Jiangsu Province. We have proposed some policy recommendations, which include paying attention to the quality of development of urbanization, adjusting the industrial structure, making changes to lifestyles, and so on.
In coal mine fire rescues, if the abnormal increase of gas concentration occurs, it is the primary thing to analyze the reasons and identify sources of the abnormal forming, which is also the basis of judge the combustion state of fire area and formulate proper fire reliefs. Nowadays, related researches have recognized the methane explosion as the source of high concentration of H2 formation, but there are few studies about the conditions and reaction mechanism of gas explosion generating high concentration of H2.Therefore, this paper uses the chemical kinetic calculation software, ChemKin, and the 20L spherical explosion experimental device to simulate the generating process and formation conditions of H2 in gas explosion. The experimental results show that: the decomposition of water vapor is the main base element reaction (R84) which leads to the generation of H2.The free radical H is the key factor to influence the formation of H2 generated from gas explosion. With the gradual increase of gas explosion concentration, the explosive reaction becomes more incomplete, and then the generating quantity of H2 increases gradually. Experimental results of 20L spherical explosion are consistent with the change trend about simulation results, which verifies the accuracy of simulation analysis. The results of explosion experiments show that when gas concentration is higher than 9%, the incomplete reaction of methane explosion increases which leads to the gradual increase of H2 formation
The primary goals of this study were to quantify the composition and size of bud banks and to evaluate the roles of bud banks of main dominant species Leymus chinensis (Trin.) Tzvel. and Carex duriuscula C.A. Mey. in population maintenance over a 2-year period. The four experimental plots were in early, early-mid, middle and late seral stages of a flooded restoration succession after they had approximately 12, 10, 8, and 6 months’ flood durations in the Songnen meadow, China. Five quadrats (each 0.25 ´ 0.25 m in area and 30 cm deep) were each sampled in four seral spots. The differences of L. chinensis and similarity of C. duriuscula in bud bank characteristics persisted in the studied seral stages from year to year. In each seral stage, rhizome buds comprised most of the L. chinensis bud banks in 2003; in 2004, juvenile tillers predominated. Rhizome buds consisted of the majority of C. duriuscula bud banks throughout the study period. The bud densities of L. chinensis and C. duriuscula experienced a significant linear increase with the increase of tiller density at different seral stages each year, but the slopes of these relationships in L. chinensis were higher than those in C. duriuscula. The total bud densities of C. duriuscula showed a significant linear decrease corresponding to the increase of those of L. chinensis from the early to the late seral stage in 2003 and 2004. Bud banks are vital for population maintenance and the number of bud banks is a good predictor of population dynamics.
It is important to evaluate the deformation and failure of sandstone in the foundation engineering of coast, river bank and lake shore. While the deformation and failure of sandstone is a comprehensive result of energy release and dissipation, and energy release is the internal reason which leads to global failure of the sandstone. The experimental analysis is conducted on the character of energy revolution of the sandstone specimen by rating loading and unloading, and the catastrophe model is followed in analyzing elastic strain energy accumulation and release in rock deformation and failure. The index based on elastic energy release is proposed to assess the rock brittleness. It is found that increasing water content is to relieve energy release and catastrophe failure of the rock specimen, and weakening the capacity of elastic energy storage. The peak and residual values of elastic energy are raised as the confining pressure increases, and the post-peak released energy decreases progressively. The confining pressure strengthens energy storage and inhibits energy release of the rock specimen, and saturation of rock will weaken this inhibit effect. The brittleness index decreases with increasing confining pressure as the rock specimen transforming from brittle to ductile
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