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A new functional porous carbons (PC-WF) is prepared by activation-pyrolysis method use waste cotton fabrics (WF) as an abundant, cheap and available precursor for removal of Brilliant Crocein (BC-GR) and Cationic Red 2GL (CR-GL) from aqueous phase. The PC-WF was characterized by BET, FTIR, SEM, and XRD techniques, the surface area, total pore volume, average pore diameter was found as 1463.5 m2 g-1, 0.783 cm3 g-1 and 2.14 nm, respectively. The influences on BC-GR and CR-GL adsorption of various experimental factors such as initial concentration and temperature were investigated. Adsorption kinetics was found to be best represented by the pseudo-second order model. The adsorption capacity was 319.8 mg g-1 for BC-GR and 842.5 mg g-1 for CR-GL at 30 °C, respectively. The results indicate that for waste cotton fabrics in particular, the practical application of this process to the production of porous carbon would be possible. 相似文献
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Mingshi Li Chengquan Huang Wenjuan Shen Xinyu Ren Yingying Lv Jingrui Wang Zhiliang Zhu 《林业研究》2016,27(6):1329-1341
Forest losses or gains have long been recognized as critical processes modulating the carbon flux between the biosphere and the atmosphere. Timely, accurate and spatially explicit information on forest disturbance and recovery history is required for assessing the effectiveness of existing forest management. The major objectives of our research focused on testing the mapping efficacy of the vegetation change tracker (VCT) model over a forested area in China. We used a new version of VCT algorithm built upon the Landsat time series stacks (LTSS). The LTSS consisted of yearly image acquisitions to map forest disturbance history from 1987 to 2011 over the Ning-Zhen Mountains, Jiangsu Province of east China. The LTSS consisted of TM and ETM+ scenes with different projections due to distinct data sources (Beijing remote sensing ground station and the USGS EROS Center). The validation results of the disturbance year maps showed that most spatial agreement measures ranged from 70 to 86 %, comparable with the VCT accuracies reported for many places in USA. Very low accuracies were identified in 1995 (38.3 %) and 1992 (56.2 %) in the current analysis. These resulted from the insensitivity of the VCT algorithm to detect low intensity disturbances and also from the mis-registration errors of the image pairs. Major forest disturbance types existing in our study area were identified as agricultural expansion (39.8 %), urbanization (24.9 %), forest management practice (19.3 %), and mining (12.8 %). In general, there was a gradual decreasing trend in forest cover throughout this region, caused principally by China’s economic, demographic, environmental and political policies and decisions, as well as some weather events. While VCT has largely been used to assess long term changes and trends in the USA, it has great potential for assessing landscape level change elsewhere throughout the world. 相似文献
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The effects of ammonia and nitrite on vigour, survival rate, moulting rate of zoea of blue swimming crab, Portunus pelagicus, were studied. A total of five nitrite-N treatments (26.67, 53.34, 106.68, 213.36, 426.72 mg/l) and a control (no nitrite-N added) were
set up for the acute nitrite-N toxicity experiment; a total of five ammonia-N treatments (8.43, 16.86, 33.72, 67.44, 134.88 mg/l)
and a control (no ammonia-N added) were set up for the acute ammonia-N toxicity experiment. The results showed that the vigour,
survival rate and moulting rate of zoea of the blue swimming crabs exposed to over 53.34 mg/l were significantly different
(P < 0.05) from the control group. The zoea LC50 values (mg/l) of nitrite-N were 179.47, 76.56, 66.70, 37.49, 25.01, 25.35, 25.34 mg/l for 24, 36, 48, 60, 72, 84, 96 h, respectively.
The vigour, survival rate and moulting rate of zoea of the blue swimming crabs exposed to over 16.86 mg/l were significantly
different (P < 0.05) from the control group. The zoea LC50 values (mg/l) of ammonia-N were 51.04, 39.62, 38.72, 24.43, 16.90, 13.42, 11.16 mg/l for 24, 36, 48, 60, 72, 84, 96 h, respectively.
The zoeae are highly sensitive to ammonia and nitrite, and the toxicity of ammonia and nitrite on Portunus pelagicus decrease with development of this crab. 相似文献
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Kelsey T. Young Kevin K. Lahmers Holly S. Sellers David E. Stallknecht Rebecca L. Poulson Jerry T. Saliki Stephen Mark Tompkins Ian Padykula Chris Siepker Elizabeth W. Howerth Michelle Todd James B. Stanton 《Journal of veterinary diagnostic investigation》2021,33(2):202
RNA viruses rapidly mutate, which can result in increased virulence, increased escape from vaccine protection, and false-negative detection results. Targeted detection methods have a limited ability to detect unknown viruses and often provide insufficient data to detect coinfections or identify antigenic variants. Random, deep sequencing is a method that can more fully detect and characterize RNA viruses and is often coupled with molecular techniques or culture methods for viral enrichment. We tested viral culture coupled with third-generation sequencing for the ability to detect and characterize RNA viruses. Cultures of bovine viral diarrhea virus, canine distemper virus (CDV), epizootic hemorrhagic disease virus, infectious bronchitis virus, 2 influenza A viruses, and porcine respiratory and reproductive syndrome virus were sequenced on the MinION platform using a random, reverse primer in a strand-switching reaction, coupled with PCR-based barcoding. Reads were taxonomically classified and used for reference-based sequence building using a stock personal computer. This method accurately detected and identified complete coding sequence genomes with a minimum of 20× coverage depth for all 7 viruses, including a sample containing 2 viruses. Each lineage-typing region had at least 26× coverage depth for all viruses. Furthermore, analyzing the CDV sample through a pipeline devoid of CDV reference sequences modeled the ability of this protocol to detect unknown viruses. Our results show the ability of this technique to detect and characterize dsRNA, negative- and positive-sense ssRNA, and nonsegmented and segmented RNA viruses. 相似文献