facing the problem of VOCs pollution, VOCs concentrations in urban Tianjin have been measured to identify their possible sources. Using positive matrix factorization, seven VOC sources are identified in urban Tianjin ...
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Energy consumption data of 66 iron and steel firms in China were used to analyze the temporal variation of energy intensity in China's iron and steel industry and to characterize energy consumption differences amo...
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Graphene-embedded carbon fiber (GFC) film has been fabricated by using filamentous fungus ( Aspergillus niger ) as carbonizable fibers to drive the graphene nanosheets to embed in the hyphae network system and then ca...
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Graphene-embedded carbon fiber (GFC) film has been fabricated by using filamentous fungus ( Aspergillus niger ) as carbonizable fibers to drive the graphene nanosheets to embed in the hyphae network system and then carbonizing at 700 °C. The molecular structure of the GFC film is primarily composed of aromatic components, and the film is doped by N (8.62%) and O (8.12%) elements. The conductivity of the final product reaches as high as 0.71 S cm −1 . The GFC film serves as the conductive interlayer to greatly improve the performance of Li–S batteries including capacity retention and rate capability. By inserting the GFC film, the battery can deliver a capacity of ~700 mAh g −1 after 300 cycles at 1 C. Even performed at 5 C, it is able to deliver a reversible capacity of more than 650 mAh g −1 . This research presents a facile and effective method for the fabrication of superior macroscopic carbon monolith, which holds great potential in other forms of electrochemical energy storage.
Particles have become an important factor in environmental quality of heritage preservation. Aiming to explore the air quality of the museum, this study conducted a series experiment in a museum in Shanghai, China. Th...
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Particles have become an important factor in environmental quality of heritage preservation. Aiming to explore the air quality of the museum, this study conducted a series experiment in a museum in Shanghai, China. The result showed that the mass concentrations indoors of coarse particles, fine particles and ultrafine particles were about 20.50∼24.38μg/m, 23.39∼24.08μg/m and 16.02∼17.48μg/m, respectively. Over 97 % of particles were belonged to PM1 (diameter 42-, NO3-, NH4+ peaked at the particle size ranged from 0.32 to 0.56μm;Na+, Cldistributed uniformly;K+ appeared bi-modals with peaks in the size ranges of 0.32∼0.56μm and 3.2∼5.6μm, respectively. Mg+ concentrated in size range of 3.2∼5.6μm, and Ca+ in the particles with size range of 1.8∼3.2μm. Total organic acids distributed uniformly, acetate ion mass concentration was 1.238μg/m which was higher than formate ion and oxalate ion.
A population of rice brown planthopper (BPH) Nilaparvata lugens collected from a paddy field in Hangzhou was successively reared on susceptible rice Taichung Native 1 (TN1) in a laboratory free from insecticides f...
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A population of rice brown planthopper (BPH) Nilaparvata lugens collected from a paddy field in Hangzhou was successively reared on susceptible rice Taichung Native 1 (TN1) in a laboratory free from insecticides for more than 14 generations. The changes in susceptibility to insecticides and ecological fitness on different resistant rice varieties were monitored in each generation. The resistance ratio to imidacloprid sharply declined with the succession of rearing generations without insecticides from 359.94-fold at F1 to 6.50-fold at F14 compared with the susceptible strain, and the resistance ratio to chlorpyrifos was from 9.90-fold at F1 to 5.94-fold at F14. Nymphal duration and weights of newly hatched female adults were significantly affected by rice variety, generation and their interactions, but nymphal survival was significantly affected by the generation only. The ratio of brachypterous adults in males was affected by the generation and generation × variety interaction, whereas no difference was found in females. Nymphal duration extended with increasing generations, and the female nymphal duration was shorter in the susceptible variety TN1 than those in the resistant varieties IR26 and IR36. In addition, the female adult weight in TN1 was higher than those in IR26 and IR36. These results indicated that the resistance of field BPH population to insecticides was reversed after several generations of no-exposure to insecticides, and the ecological fitness in TN1 was higher than those in IR26 and IR36. These findings suggested the rational and reduced use of insecticides in combination with the manipulation of resistant rice varieties would be effective for BPH management.
In imaging measurements on the fluid flow, the quality of particle image is essential to the outcomes of the velocity field. The method to eliminate the problems of refraction and reflection is to match the refractive...
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In imaging measurements on the fluid flow, the quality of particle image is essential to the outcomes of the velocity field. The method to eliminate the problems of refraction and reflection is to match the refractive indices of the working fluid and the surrounding solid wall. In this article, a comprehensive summary of the refractive index matching method was presented. Three fluid materials, two organic and one non-organic was used to conduct index matching and their effect were compared. Results show the perfect index matching is effective to improve the measurement accuracy of imaging measurements.
The three dimensional three component(3D3C) flow field inside hydrocyclone was investigated using Volumetric 3-component Velocimetry(V3V). To improve the spatial resolution of the measurement, a refractive index match...
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The three dimensional three component(3D3C) flow field inside hydrocyclone was investigated using Volumetric 3-component Velocimetry(V3V). To improve the spatial resolution of the measurement, a refractive index matching method is used in the experiment. The three components of the velocity in the hydrocyclonic flow is measured, and the measurement produced huge amount of data, which enabled detailed analysis of the hydrocyclonic flow field. The tangential and axial is quasi-symmetric while the radial velocity is non-axisymmetric. The radial velocity is one order smaller in value than the other two component. Results show V3 V with index matching is a robust method to the measurement of hydrocyclone flow field.
The pyrolysis characteristics of kitchen waste were studied and the optimal pyrolysis condition was obtained by analyzing the thermogravimetric curves(TG/DTG). Then a pyrolysis experiment was carried out using externa...
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ISBN:
(纸本)9783038353201
The pyrolysis characteristics of kitchen waste were studied and the optimal pyrolysis condition was obtained by analyzing the thermogravimetric curves(TG/DTG). Then a pyrolysis experiment was carried out using external heated rotary furnace with the throughput at 5kg/h and the heating rate ranging from 50°C/min to 200°C/min. In this experiment, the 3-phase products were collected separately and the distribution was tested. The composition and thermal value of the products were also analyzed.
Reduction of noncrop habitats, intensive use of pesticides and high levels of disturbance associated with intensive crop production simplify the farming landscape and bring about a sharp decline of biodiversity. This,...
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Reduction of noncrop habitats, intensive use of pesticides and high levels of disturbance associated with intensive crop production simplify the farming landscape and bring about a sharp decline of biodiversity. This, in turn, weakens the biological control ecosystem service provided by arthropod natural enemies. Strategic use of flowering plants to enhance plant biodiversity in a well-targeted manner can provide natural enemies with food sources and shelter to improve biological control and reduce dependence on chemical pesticides. This article reviews the nutritional value of various types of plant-derived food for natural enemies, possible adverse effects on pest management, and the practical application of flowering plants in orchards, vegetables and field crops, agricultural systems where most research has taken place. Prospects for more effective use of flowering plants to maximize biological control of insect pests in agroecosystem are good but depend up on selection of optimal plant species based on information on the ecological mechanisms by which natural enemies are selectively favored over pest species.
Rice black-streaked dwarf virus(RBSDV),a member of genus Fijivirus within the family Reoviridae,can cause a significant reduction in cereal crops *** has 10 genomic segments of double stranded RNA,and the genome is en...
Rice black-streaked dwarf virus(RBSDV),a member of genus Fijivirus within the family Reoviridae,can cause a significant reduction in cereal crops *** has 10 genomic segments of double stranded RNA,and the genome is encapsidated by two protein shells,one outer capsid and one
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