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Pharmaceutical wastewaters are generated through complex manufacturing processes that contain a variety of organic and inorganic constituents, and are usually characterized by a high concentration of chemical oxygen demand (COD), suspended solids, dissolved solids (salts), toxicity, and refractory compounds. In this paper, wet peroxide oxidation (WPO) was adopted to treat pharmaceutical wastewater. Central composite design, an experimental design for response surface methodology (RSM), was used to create a set of 30 experimental runs needed for optimizing operating conditions. The experimental results show that WPO could effectively reduce COD by 97.5% at optimum conditions: temperature is 260ºC, H₂O₂ excess (HE) is 0, the initial concentration of pharmaceutical wastewater is 45,000 mg/L, and reaction time is 10 min. WPO process is possibly suitable for a primary treatment for pharmaceutical wastewater. Response surface methodology (RSM) could be effectively adopted to optimize the operating multifactors in a complex WPO process.
Soil erosion tends to occur with rainfall runoff, thus leading to grave soil and water loss. An increase of water content in soil caused by rain makes the loss of matrix suction and the decrease of shear strength obvious, and will promote soil erosion. The soil-water characteristic curve (SWCC) can be used to describe the relationship between the water content and the matrix suction in unsaturated soil. For this paper we studied the SWCCs of the granite residual soils in a collapsing erosion area in Jiangxi Province, China. A GEO-Experts pressure plate extractor was used to measure SWCCs for soils with different dry density, grain size, drying and wetting cycles, and lime content. The initial dry density has a significant impact on SWCC. With increasing dry density, the suction was decreased for the same water content. The larger the grain size, the greater the suction value for the same volumetric water content. Under the same suction, the volumetric water content decreases as the lime percentage increases and water stability improves. SWCCs of the drying and wetting cycle demonstrate the hysteresis phenomenon. The area of the hysteresis loop decreased with the increase of the dry density and drying and wetting cycle number. It also became small when the soils were mixed with lime. In this paper, the Van Genuchten model, the Fredlund and Xing model, and the Gardner model were used to fit the experimental data of SWCCs. The presented fitting parameters show that the residual sum of squares is less than 0.002. All the experimental data fit well to three models for SWCC. The results indicated that the simulated value of the Gardner model does provide best agreement with the measured value. These results will provide an important basis for the further study of the soil collapsing erosion process and soil cover design.
Recent studies suggest that horizontal gene transfer (HGT) played a significant role in the evolution of eukaryotic lineages. We here review the mechanisms of HGT in plants and the importance of HGT in land plant evolution. In particular, we discuss the role of HGT in plant colonization of land, phototropic response, C4 photosynthesis, and mitochondrial genome evolution.
The amount of eco-water resources reflects the land surface water conservation capability, and the underlying surface condition in the hydrologic cycle. In the upper Minjiang River Basin, the amounts of eco-water resources were retrieved from remotely sensed data during 1992 to 2005. Through regression analysis between the retrieved eco-water data and the climate hydrological data mainly including the temperature, the precipitation, and the runoff in the same period, the model of eco-water driving force affecting the evolvement of runoff was established. The accuracy analysis indicates that the model can well describe the relationship between dry season runoff and its driven factors, the measured data validation proves that the model has high precision and good practicability. The eco-water remote sensing inversion provides a valid method to quantify the land surface water conservation capability, and suggests an interesting approach for the driving function quantitative researches of underlying surface factor in the hydrologic cycle
Rapid and extensive economic development in China has resulted in a dramatic increase in the consumption of energy and resources with negative ecological effects. This study sought to define the concept of social-ecological systems (SES) resilience to determine whether a given system can effectively withstand these adverse effects per its quantitative level of resilience. The information entropy method and set pair analysis were adopted to determine SES resilience indicators, including the vulnerability and response capacity of social, economic, and ecological subsystems. Thirty-one provincial regions in mainland China were taken as examples and their respective SES resilience levels were empirically measured. The driving mechanisms of resilience were identified based on the correlations of vulnerability and response capacity with resilience. Provinces with higher resilience were identified along the eastern coast of China, whereas provinces with lower resilience were located in the western and central parts of the country. The direction and rate of the factors differed and were uncertain, but a quadratic linear relationship between a driving factor and resilience was clearly identified. The results also confirmed that the set pair analysis method is suitable for SES resilience measurement.
The length–weight relations (LWR) were estimated for 20 fish species from the Pearl River, South China. A total of 3610 specimens representing 10 families were used to estimate the relation parameters. The b values in the LWR (W = aLb) ranged from 2.068 for Odontamblyopus lacepedii (Temminck et Schlegel, 1845) to 3.423 for Pseudogobius javanicus (Bleeker, 1856). The LWR with high coefficient of determination (r2) is significant for all the species. The r2 value ranged from 0.919 to 0.993. This study presents the first reference on length–weight relations for 7 species and new records of maximum total length for 6 species. The results may be helpful in future fisheries studies in this area.
Microcystis aeruginosa is one of the most common blue-green algae species that forms harmful water bloom, which frequently causes serious ecological pollution and poses a health hazard to animals and humans. To understand the progression of algal blooms and to provide a theoretical basis for predicting and preventing the occurrence of algal blooms and reducing the harm of algal bloom to environment, we investigated the diurnal variation of photosynthesis, ATP content and cell division in M. aeruginosa PCC7820. The results showed that the photosynthesis and ATP content of M. aeruginosa PCC7820 exhibited clear circadian rhythm with a period of approximately 24 h and that the periodic rhythms continued for at least three cycles under continuous light conditions. Furthermore, the period length showed that a temperature compensation effect and changes in light cycle or temperature could reset the phase of circadian rhythm. These results indicate that the circadian rhythms of physiological process in M. aeruginosa PCC7820 are controlled by the endogenous circadian clock. Examinations of the number, size and cytokinin content of cells also reveal that the cell division of M. aeruginosa PCC7820 with the generation time of 38.4 h exhibits robust circadian rhythms with a period close to 24 h. The circadian rhythms of cell division may be generated by a biological clock through regulation of the cell division phase of M. aeruginosa PCC7820 via a gating mechanism. The phases in which cell division slows or stop recur with a circadian periodicity of about 24 h.
A new genus and species Multiramificans ovalis gen. and sp. nov. of the family Siphlonuridae s.Z., is described from the Middle Jurassic Jiulongshan Formation of the Daohugou, Inner Mongolia in China. Detailed description and illustration of the specimen along with a brief review of fossil Siphlonuridae s.l. are given. The problems of association between nymphs and adults, and palaoenvironment are briefly discussed.
Excessive trafficking of leukocytes can lead to serious tissue injury. Here, four regioselectively sulfated chitosans were assessed as inhibitors of HL-60 leukocyte binding to P-selectin, by investigating their effect on leukocyte adhesion to CHO cells expressing human P-selectin under static and flow conditions. The results show that the sulfochitosans exhibit inhibitory activity in this general order: heparin > N-sulfated/6-O-sulfated chitosan ≥ 3-O,6-O-sulfated chitosan > 6-O-sulfated chitosan ≫ N-sulfated chitosan. This suggests that the sulfation of the double site in chitosan is essential for efficient inhibition of P-selectin-mediated HL-60 leukocyte adhesion and that such sulfochitosans may have potential as therapeutic agents against inflammatory disease.
This study focused on the function of hnRNP-R in the regulation of c-fos expression. We demonstrated that hnRNP-R accelerated the rise and decline phases of c-fos mRNAs and Fos proteins, allowing PMA to induce an augmented pulse response of c-fos expression. Then, we examined the role of the c-fos-derived AU-rich element (ARE) in hnRNP-R-regulated mRNA degradation. Studies with the ARE-GFP reporter gene showed that hnRNP-R significantly reduced the expression of GFP with an inserted ARE. Moreover, immunoprecipitation-RT-PCR analysis demonstrated that in R28 cells and rat retinal tissues, the c-fos mRNA was co-immunoprecipitated with hnRNP-R. These findings indicate that hnRNP-R regulates the c-fos expression in retinal cells, and that the ARE of c-fos mRNAs contributes to this regulation.
With the liquid crystal displays (LCDs) being widely used in televisions, notebooks, and mobile phones, etc., large quantities of LCDs are entering into their end-of-life stage for treatment. If not treated properly, a loss of resources and undesirable impacts on the environment and human health can occur. In order to treat the waste LCDs in an efficient and environmentally friendly way, a combined process of physical methods was proposed to separate and recover materials from waste LCDs in the present study. On the basis of primary disassembly, two key processes (including liquid crystals removal and the recovery of polarizer and glass) were studied. Liquid crystals were removed from the panel glass by dissolving in isopropyl alcohol solution (16.7 vol.%) assisted with ultrasound. Recovery of polarizer and glass was achieved through mechanical crushing and gravity concentration. Results show that approximately 100 wt.% of liquid crystals were removed after dissolving for 45 min at 60ºC. Up to 79.7 wt.% of polarizer was separated from glass and its average content in the recovered product was 90.3 wt.%.
Changes in precipitation patterns and the deposition of atmospheric nitrogen (N) increase the possibility of altering soil carbon (C):N:phosphorus (P) stoichiometry through their effects on soil C and nutrient dynamics, especially in water- and N-limited ecosystems. We conducted separate 2-year watering and N addition experiments, and examined soil C:N:P stoichiometry, relative growth rate, and leaf N resorption traits of Glycyrrhiza uralensis Fisch in a desert steppe of northwestern China. Our objectives were to determine how soil C:N:P stoichiometry responded to climate change, and its indications for plant growth and N resorption. The results showed that additional water increased N loss and thus decreased N availability, resulting in high N resorption from senescing leaves of G. uralensis. N addition increased N availability, consequently reducing plant N dependence on leaf resorption. High relative growth rates occurred with intermediate N:P and C:N ratios, while high N resorption occurred with a low N:P ratio but a high C:N ratio. Our results indicate that soil C:N:P stoichiometry also could be a good indicator of N limitation for desert steppe species. Altered soil C:N:P stoichiometry affects the N strategy of plants, and will be expected to further influence the structure and function of the desert steppe community in the near future.
Based on specimen examination and previous records, we provide a checklist including 146 species from 51 genera and 10 tribes of the weevil subfamily Ceutorhynchinae in China. Of these species, the following 18 are reported in China for the first time: Amalus scortillum (Herbst, 1795), Ceutorhynchus filiae Dalla Torre, 1922, Dieckmannius ingensColonnelli, 1993, Dieckmannius sexnotatus (A. Schultze, 1899), Nedyus quadrimaculatus (Linnaeus, 1758), Zacladus stierlini (A. Schultze, 1902), Auleutes epilobii (Paykull, 1800), Hypurus bertrandi (Perris, 1852), Hypurus portulacae (Marshall, 1916), Neoplatygaster venusta (Faust, 1885), Belonnotus tenuirostris (Marshall, 1917), Mecysmoderes fulvus (Roelofs, 1875), Xenysmoderes stylicornis (Marshall, 1934), Mononychus ireos (Pallas, 1773), Rhinoncus jakovlevi Faust, 1893, Rutidosoma globulus (Herbst, 1795), Rutidosoma graminosum (Gistel, 1857) and Rutidosoma koreanumKorotyaev & Hong, 2004.
While simultaneous processing of heavy metal-rich waste and municipal sewage sludge (MSS) in cement kilns may be a useful measure for protecting the environment, simultaneous co-disposal of these two types of wastes has seldom been reported in detail. In this study, we examined how MSS influenced the fixation of heavy metals during clinkerization and determined the main controlling mechanisms through analyzing the polymorphism of tricalcium silicate (C₃S), mineral composition of MSS, and element distribution in the clinker. The results showed that MSS had negative effects on the fixation of heavy metals, with reductions of 12.9%, 8.7%, 3.2%, and 1.2% in the amounts of Cu, Ni, Cr, and Zn fixed, respectively. These changes were mainly attributed to the presence of trace elements – in particular phosphorus from the MSS, which caused the polymorphism of C₃S to change in the order: rhombohed ral→monoclinic→triclinic. As well as occurring as C₂S-C₃P, phosphorus also occurred in new phases of K₂NiP₂O₇, K₂Cu(PO₃)₄, and Cu₄O(PO₄)₂ in cement clinker. In general, trace elements from the MSS, especially phosphorus, decreased the solubility of heavy metals in cement clinker through changing the polymorphism of C₃S, and resulting in a decrease in the fixation ratios of heavy metals.
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