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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.
Coal, as one of the most important sources of energy around the world due to the intensity of its exploiting and utilization, causes increasingly serious ecological problems, especially air pollution. Large amounts of pollutants are emitted during coal combustion, with NOx and SO₂ being the principal compositions. Therefore, desulfurization and denitrification are extremely urgent. Many technologies have been developed and applied. Our paper introduces mature and new flue gas denitration and desulfurization technologies along with their processing principles, industrial status, merits, and demerits. The combination of SNCR and SCR technology avoids their respective shortcomings and improves denitrification efficiency and economy. Based on the present situation, future trends are put forward. Synergetic, effective, and cheap desulfurization and denitration technologies will be our focus.
The heating mode of a regenerative electric boiler in China’s rural area includes many problems such as the increase of heating cost, the high expense of government subsidies and tr investment cost, etc. Consequently, this paper proposes a new heating method that combines a regenerative electric boiler with distributed photo-voltaic power generation. The photovoltaic software PVsyst was used to simulate generating capacity, and a system-wide economic efficiency calculation model was established. Taking a family in Gaobeidian City as an example, a comparative analysis of the method before and after optimization was conducted. The results showed that the new heating method has good economics, environmental benefits and promotional value. This new rural household heating method is of great significance for realizing the rural household energy cleanness in the Beijing-Tianjin-Hebei metropolitan region, promoting the green and low-carbon development of rural energy, and realizing beautiful rural construction.
In order to study the impact of Pb, Cd, Zn, and Cu released by Pb-Zn tailings on soil enzymes and soil properties involving soil carbon and nitrogen cycle processes, 32 soil samples were collected from 2 different types of agricultural fields (one for growing corn and one for growing rice) contaminated by Pb-Zn tailings close to Sidi village in southwestern China. The results revealed that the paddy fields were seriously contaminated by Pb-Zn tailings compared with cornfields. Under the Pb-Zn tailings contamination, the population of fungi and actinomycetes as well as the activities of the soil enzymes (urease, invertase, and cellulase) in cornfields were significantly higher than those in the paddy fields. In addition, the results from path analysis showed that urease, invertase, and acid phosphatase were negatively correlated with DTPA-extractable Cd, Pb, and Zn (the direct path coefficients were -0.336, -0.314, and -0.591, respectively). Soil microorganisms and enzyme activities involving soil organic carbon and nitrogen decomposition and stabilization were decreased due to the toxic Pb-Zn tailings. Therefore, soil organic carbon and total nitrogen accumulate and an “elusive” carbon and nitrogen pool forms in the paddy fields compared with cornfields in the Pb-Zn tailings-contaminated karst area.
A two-stage vertical-flow constructed wetland (VFCW) was built to advanced treatment of secondary effluent containing organic and inorganic nutrients (nitrogen and phosphorus) from a municipal sewage treatment plant in Beijing, China. The results showed that the VFCW effluent achieved 66-83% and 81-90% removal for COD and TP, respectively. Meanwhile, NH₄⁺-N and TN were almost completely removed during stable operation of the wetland system. The VFCW effluent concentrations of COD, TN, and TP were less than 30 mg·L⁻¹, 1.5 mg·L⁻¹, and 0.3 mg·L⁻¹, respectively, which can meet the environmental quality standards for surface water in China. Because of the special design, the better performance of the VFCW was that it allowed the treatment of wastewater under multiple aerobic, anoxic, and anaerobic conditions sequentially in different heights of the CW unit. New media materials, rice husks, and steel slag were the key to the efficient removal of TN and TP. This technology could be adopted to improve the secondary effluent quality.
Based on the energy consumption data of power industry in the Beijing-Tianjin-Hebei region from 1995 to 2014, our paper first estimated CO₂ emissions using the IPCC carbon accounting methods. Then, starting from the perspective of the power industry chain – including power generation, transmission, and final consumption – we established the hierarchical LMDI decomposition model; decomposed driving factors of CO₂ emissions into effects of fuel mix; the coal consumption rate; power generation structure; the ratio of power generation to consumption, transmission, and distribution losses; production sectors’ electricity intensity; industrial structure; household electricity intensity; economic scale; and population size. Results show that: 1. During 1995-2014, CO₂ emissions of power industry in the Beijing-Tianjin-Hebei region developed in fluctuation and showed a rising trend in general, with annual average growth rate of 5.93%. 2. The factors that drive the growth of CO₂ emissions from the power industry in the Beijing-Tianjin-Hebei region are, in order, economic scale, population size, transmission and distribution losses, and industrial structure, with a contribution rate of 150.70%, 20.80%, 8.86%, and 8.83%. The factors that drive CO₂ emissions reduction are production sectors’ electricity intensity, the coal consumption rate, the ratio of electricity generation and consumption, household electricity intensity, power generation structure, and fuel mix, with a contribution rate of -45.97%, -22.38%, -19.41%, -0.62%, -0.49%, and -0.32%, respectively
Based on the significant differences in the resistance to Sclerotinia sclerotiorum between two Brassica napus cultivars, ZhongR888 and Zhongyou821, near isogenic lines (NILs) were established. The resistance differences between Zhongyou821 and BC₅ progeny (the fifth generation from a cross between Zhongyou821 and ZhongR888 with Zhongyou821 as successive backcross parent) was displayed by cDNA-AFLP and differential transcripts-derived fragments (TDFs). The full-length cDNA of 1,707 bp with 1,323 bp open reading frame (ORF, open box), named Rsk was identified by RT-RACE from the resistance related fragment 40-2 in Zhongyou821. It encoded a protein of 440 amino acid residues, which contained a putative extracellular domain, a transmembrane domain, and an intracellular domain. Analysis of the deduced amino acid sequence of Rsk revealed that it had high homology to Arabidopsis thaliana kinase involved in protein binding, and had a conserved region of LRR-RI, indicating it might be a member of leucine-rich repeats, ribonuclease inhibitor-like subfamily. DNA sequences of 1,685 bp and 1,703 bp without an intron were also identified from Zhongyou821 and BC₅, respectively. Expression analysis showed that Rsk might play a role in disease resistance pathways.
Typical tripod foundations are designed using deterministic computational models according to relevant standards and codes. However, for more cost-safety balanced design, uncertainties in significant parameters should be considered in preliminary design to ensure meeting a specific probabilistic safety target in the context of the complex configuration of a tripod structure. In this article, uncertainties associated with design parameters and modelling errors are considered using Monte Carlo simulations, in order to determine the key structural design parameters, and to determine the optimal balance between design parameters and design requirements. A Spearman rank-order correlation based analysis is carried out to understand the effects of design variables on maximum deformation, total weight, and natural frequency, and to have insight about important design parameters for improvement of a preliminary design. It is found that the tower diameter has the most significant effect on the maximum displacement on the hub as validated through engineering case studies. In addition, a statistical framework, which identifies influential design parameters and provides reliability evaluation, is proposed for the structural design of a tripod OWT system. The design cases considered in this study indicate that a simple deterministic design check cannot guarantee the required reliability level of the structure, and the cost-safety balance can be achieved by a reliability analysis with the consideration of the uncertainties in the structure
The aim of this study was to assess the effect of sodium alginate-immobilized bacteria and ultrasonic assistance on the biodegradation of oestrogens in soil. The studied oestrogens were oestrone (E1), oestradiol (E2), oestriol (E3), 17α-ethinylestradiol (EE2), and bisphenol-A (BPA). A central composite design was developed to determine the optimal conditions of the three variables (ultrasound time, sodium alginate concentration, and amount of sodium alginate beads) for the removal of oestrogens. Moreover, the experiment utilized a quantitative structure-biodegradation relationship (QSBR) to analyze the effect of the estrogenic physicochemical properties on the enhancement of the biological degradation mechanism. The results indicated that the optimal conditions are an ultrasound time of three min, a sodium alginate concentration of 3%, and 4 g of sodium alginate beads. These conditions resulted in removal rates of 100%, 100%, 93%, 96.47, and 51.87% for E1, E2, EE2, BPA, and E3, respectively, after seven days. These rates were 1.7, 1.4, 1.3, 1.2, and 2.1 times the microbial degradation rate of the suspended state, respectively. Based on a Pearson correlation analysis, the oestrogen molecule polar surface area (PSA) and hydrophobicity (represented by logKow) were significantly related to the effect of biodegradation. An analysis of the OSBR model (with the oestrogen biodegradation rates as a dependent variable and PSA and logKow as independent variables) indicated the following: PSA negatively correlated and logKow positively correlated with oestrogen removal, and these effects were synergistic. Therefore, sodium alginate/ultrasound assistance can significantly improve the biodegradation rates of oestrogens in soil, while simultaneously adjusting other environmental conditions would influence and control the biodegradation processes of oestrogens.
An analysis is made on the past and future trends of wastewater treatment in Beijing. Over the past several decades, great efforts have been made by Beijing to improve the urban wastewater treatment technology, reclaim municipal wastewater, and promote water reclamation and reuse. Until now, the utilization volume of reclaimed water has been increasing continuously. Generally, there are four categories of wastewater treatment plants (WWTPs) in Beijing. And the most mainstream wastewater treatment method in Beijing is aerobic biological process, thereinto the advanced treatment methods of WWTPs, including membrane bioreactor (MBR), biological aerated filter (BAF), and chemical oxidation. However, both the existing conventional and advanced treatment processes mainly aim at the remediation of COD, ammonia nitrogen, total nitrogen, total phosphorus, and other conventional organic pollutants. Micro pollutants such as persistent organic pollutants (POPs) are not considered in the design of WWTPs. The treatment and disposal issues of sludge have become an important agenda item for Beijing’s municipal government. In the future, the priority technologies for wastewater treatment in Beijing should have the features of high efficiency and stability, and lower energy consumption, and operational cost. Suitable small-scale technologies are necessary for rural areas. The existing wastewater treatment facilities must be strengthened and improved to reduce the micro-pollutants in wastewater.
Medicago sativa L. cv. Longzhong is a nutritious forage plant in dryland regions of the Loess Plateau with strong drought tolerance and broad adaptability. To understand the adaptation mechanism of alfalfa (M. sativa L. cv. Longzhong) to drought stress, growth, and physiological parameters including levels of chlorophyll content, osmotic adjustment, reactive oxygen species (ROS), and antioxidant enzymes and antioxidants were measured under simulated levels of drought (− 0.40, − 0.80, − 1.20, − 1.60, and − 2.00 MPa). The changes in M. sativa L. cv. Longzhong were compared with those of plants of M. sativa L. cv. Longdong control (Variety I) suited to moderate rainfall areas and M. sativa L. cv. Gannong No. 3 (Variety II) suited to irrigated areas. The results showed that root–shoot ratio, the chlorophyll (a + b) and osmolytes contents, the degree of lipid peroxidation and ROS production, and the levels of antioxidative enzymes and antioxidants increased significantly with increasing drought stress, whereas plant height, aboveground biomass, chlorophyll a/b ratio, leaf water potential (Ψ₁), and relative water content (RWC) decreased in response to drought. The Longzhong variety responded early to beginning drought stress (between 0 and − 0.4 MPa) compared with the controls. Under drought stress (between − 0.4 and − 2.0 MPa), the Longzhong variety had significantly higher belowground biomass, root–shoot ratio, Ψ₁, RWC, catalase (CAT) activity and reduced glutathione content than those of Varieties I and II, but hydrogen peroxide and hydroxyl free radical (OH·) contents were significantly lower. Step regression analysis showed that OH·, CAT, malondialdehyde, superoxide anion-free radical (O₂˙⁻ ), and superoxide dismutase of Longzhong had the most marked response to drought stress. In conclusion, the stronger drought tolerance of the Longzhong variety might be due to its higher water-holding capacity, root–shoot ratio, and ability to coordinate enzymatic and non-enzymatic antioxidant systems, which coordinate the peroxidation and oxidative systems.
The study on antagonistic mechanism of biocontrol strains gives the premise and basis for efficient and stable biological control. This study aimes to overcome of biocontrol agent in aspects of complicated and diversified mode of action, short-lasting and unstable efficacy in the production processes. This study elucidated the antagonistic mechanism of Bacillus cereus strain B-02 on Botrytis cinerea by detecting changes in morphology, ultrastructure and physiology in affected hyphae of Botrytis cinerea. Which provided certain theoretical and practical significance for biological control of gray mould caused by B. cinerea. B. cereus strain B-02 isolated from tomato rhizosphere mightily suppressed gray mold in tomato caused by B. cinerea. Spore germination and hyphal growth of B. cinerea were inhibited by B. cereus strain B-02. Changes of cell morphology such as distortion, shrinking and swelling were observed by SEM. TEM observation further indicated the ultrastructural alterations of hyphae, including mitochondrion reduction, un-membranous inclusion in cytoplasm, considerable thickening of cell walls, and electronic density enhancement. LSCM observation revealed the fluorescence intensity of nucleus DNA, mitochondrion DNA and reactive oxygen radical in treated hyphae were all stronger than control and the difference was significant (P < 0.01). These results indicated that the antagonistic effects of B. cereus strain B-02 on B. cinerea were likely due to a combination of abnormal synthesis of nucleus DNA and mitochondrion DNA and multifarious ultrastructural alterations in hyphal cell.
Port shoreline resources are the basis of port and shipping development, and its assessment method has become one of the hot issues in port research. On the basis of constructing a reasonable index evaluation system, this paper constructs the fuzzy evaluation matrix based on the triangular fuzzy analytic hierarchy process and constructs the fuzzy evaluation matrix by using the fuzzy comprehensive evaluation method, and obtains the maximum membership degree of the port shoreline resources. Compared with the traditional port shoreline Resource evaluation methods, the new one got more advantages in objective and quantitative. Finally, Combined with the Nanjing section of the Yangtze River as a case for verification, the results show that the model can accurately solve the problem of resource evaluation of port shoreline
Discovering how to best protect one of the most endangered animals in the world, giant pandas, has always been an important project in ecological studies. Moreover, researching the living environments of giant pandas and how to recover them is one of the most important elements to these studies. In order to more effectively protect the giant pandas and their habitats, we studied the changing of Xiaohegou nature reserve landscape for 20 years, from 1994 to 2014, based on the landscape ecology theory and “3S” techniques (geographic information systems, GIS; remote sensing, RS; global navigation satellite system, GNSS). Specifically, this paper analyzes factors such as landscape fragmentation, connectivity, disturbance degree, landscape diversity, etc. Accordingly, the research presented divides giant panda habitat into nine landscape types that include: evergreen deciduous broad-leaved mixed forest, secondary broadleaved forest, mixed coniferous and deciduous broad-leaved forests, and coniferous forest, et al. The results show that: 1) before establishing the Xiaohegou Nature Reserve in 1993, deforestation was a serious problem, as the results from the 1994 landscape fragmentation suggest. 2) Logging was rampant before the implementation of the national natural forest protection project that began in 1998. Severe damage was observed on the coniferous forest in giant panda habitat. Yet, from the high level of fragmentation that was observed in the connectivity of giant panda habitat, the results suggest 1994 was the worst. After more than ten years of recovery, from 2001 to 2014, the situation of regarding the habitat’s connectivity appears better than previous years. 3) The habitat has been impacted heavily by human disturbance from 1994 to 2001, although it has shown a slight decrease in this tendency from 2001 to 2014. 4) In the past 20 years, both the diversity and evenness indexes are showing a slow drop tendency. 5) This paper analyzes the changing situation regarding the land category evolution of giant panda habitats. Coniferous forests, the main habitat of giant pandas, decreased 6.37 hm² during these 5 years, with a rate of decrease at 1.27 hm² per annum from 1994 to 1998. In the years that followed, however, the coniferous forest recovered 4.21 hm² over the course of 15 years at the rate of 0.28 hm² per annum from 1999 to 2014, providing a reference for further nature reserve policy development.
The occurrence of 22 antibiotics, including eight quinolones, nine sulfonamides and five macrolides in water and sediment from Zizhuyuan Lake has been investigated in Beijing, China. Sediment samples were extracted by pressurized liquid extraction (PLE). Aqueous extracts from PLE and water samples were concentrated by solid-phase extraction (SPE) and detected by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI MS/MS). Antibiotics were detected in concentrations of up to 20 ng/L in water samples and 52.1 μg/kg in sediments. Quinolones were the most prevalent contaminants in water body, accounting for 63.4%, while quinolones and macrolides were prominent in sediments, accounting for 55.1% and 41.7%, respectively. The environmental risk assessment revealed that some antibiotics, in particular Ofloxacin (OFL) and Sulfamethoxazole (SMX), could cause high damage to algae and plants in the aquatic ecosystem.
Phalaenopsis is one of the world’s most popular and important epiphytic monopodial orchids. The extraordinary floral diversity of Phalaenopsis is a reflection of its evolutionary success. As a consequence of this diversity, and of the complexity of flower color development in Phalaenopsis, this species is a valuable research material for developmental biology studies. Nevertheless, research on the molecular mechanisms underlying flower color and floral organ formation in Phalaenopsis is still in the early phases. In this study, we generated large amounts of data from Phalaenopsis flowers by combining Illumina sequencing with differentially expressed gene (DEG) analysis. We obtained 37 723 and 34 020 unigenes from petals and labella, respectively. A total of 2736 DEGs were identified, and the functions of many DEGs were annotated by BLAST-searching against several public databases. We mapped 837 up-regulated DEGs (432 from petals and 405 from labella) to 102 Kyoto Encyclopedia of Genes and Genomes pathways. Almost all pathways were represented in both petals (102 pathways) and labella (99 pathways). DEGs involved in energy metabolism were significantly differentially distributed between labella and petals, and various DEGs related to flower color and floral differentiation were found in the two organs. Interestingly, we also identified genes encoding several key enzymes involved in carotenoid synthesis. These genes were differentially expressed between petals and labella, suggesting that carotenoids may influence Phalaenopsis flower color. We thus conclude that a combination of anthocyanins and/or carotenoids determine flower color formation in Phalaenopsis. These results broaden our understanding of the mechanisms controlling flower color and floral organ differentiation in Phalaenopsis and other orchids.
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