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  • Wolf posted an update 8 months, 1 week ago

    A post low strength acid extraction after anaerobic fermentation is recommended to facilitate phosphorous release and improve the total recovery rate.Global carbon cycle is closely related to the earth’s energy budget, because CO2 plays an active role in the global climate change. The higher CO2 partial pressure (pCO2) in inland water in comparison with atmosphere, causing a CO2 evasion from water to the air. However, the relationship between CO2 evasion, riverine carbon export, and hydrochemistry in watershed has remained largely unknown. This study collected 84 river water samples in Jiulongjiang River, to further address this subject on a small watershed scale. Water temperature fluctuation, riverine photosynthesis, and acidic matter input could not account for the seasonal variation of pCO2 in Jiulongjiang River. The spatial shifts of pCO2 were derived from the mixing process between headwater and soil influx. The soil influx with high pCO2 compensated the CO2 lost from evasion and caused pCO2 in Jiulongjiang River higher than the atmospheric level. The seasonal variation of pCO2 was caused by the precipitation difference between the wet season and dry season. The addition of rainwater significantly decreased the riverine pCO2 and HCO3- concentration in the wet season. The CO2 evasion rate in Jiulongjiang River was clearly higher than that in most worldwide large rivers. The annual CO2 evasion flux in Jiulongjiang River Basin was estimated about 2.48 × 105 T C/year, which was higher than the riverine total carbon export. The CO2 evasion rate exhibited significantly positive relationship with water surface area, indicating that the global CO2 evasion flux may be roughly estimated based on the observed regression relationship. Overall, our study indicated that it still requires collaborative effects to investigate the carbon dynamics in river water, more estimations of CO2 outgassing flux from river water under different hydrologic and geologic conditions are necessary.Plastic polyethylene mulch has been widely used in crop production, but also causes environmental pollution if plastic residues accumulate in soil. Biodegradable plastic mulches (BDM) are a potential solution to problems caused by polyethylene mulches, as BDMs are designed be tilled into the soil after the growing season and then biodegrade. However, the agronomic performance of BDMs still needs to be tested for comparison to polyethylene mulch. We carried out a two-year field experiment in 2018 and 2019 in a typical humid continental climate in Northeast China. Maize was planted in a ridge-furrow pattern, with mulching treatments consisting of no mulch (control), clear BDM, black BDM, clear polyethylene, and black polyethylene. Clear mulches increased soil temperature when compared to no mulch control treatments, while black mulches decreased or did not change soil temperature during the early growing season. Soil temperature and root morphology were similar between BDM and polyethylene mulches for a given type of plastic color. Maize yield did not differ across all the treatments. Maize protein, fat, N and P contents were generally higher for black BDM than other treatments, suggesting that maize quality benefited especially from black BDM. Overall, these results show that, in a humid continental climate, the agronomic performance of clear and black BDMs was equivalent to, or better than, that of polyethylene plastic mulches for maize production.Climate change is and will continue to have significant implications for agricultural systems. While adaptation to climate change should be the priority for smallholder production systems, adoption of cost-effective mitigation options in agriculture not only contributes to food security but also reduces the extent of climate change and future adaptation needs. Utilizing management data from 16,413 and 12,548 crop and livestock farmers and associated soil and climatic data, we estimated GHG emissions generated from crop and livestock production using crop and livestock models, respectively. Mitigation measures in crop and livestock production, their mitigation potential and cost/benefit of adoption were then obtained from literature review, stakeholder consultations and expert opinion. We applied the identified mitigation measures to a realistic scale of adoption scenario in the short- (2030) and long-term (2050). Our results were then validated through stakeholders consultations. Here, we present identified mes. Therefore, government should focus on facilitating uptake of these options through appropriate policy interventions, incentive mechanisms and strengthening agricultural extension programs.The occurrence of six anticancer drugs was evaluated in wastewater effluents. Several grab samples from wastewater effluent were collected throughout a year. TTNPB datasheet Capecitabine, cyclophosphamide and ifosfamide were detected at concentrations ranging from 8 to 46 ng·L-1. Capecitabine was detected in all the sampling events whereas cyclophosphamide and ifosfamide were detected less frequently. Additionally, the suitability of using pharmaceutical-polar organic chemical integrative samplers (POCIS) to monitor the target drugs in wastewater effluents was assessed. Capecitabine, ifosfamide and cyclophosphamide were detected with POCIS and showed a linear uptake over 15 days. The sampling rates, determined in situ, were used to estimate time-weighted average concentrations. A good correlation was found between the concentration of capecitabine detected with POCIS deployed during five days (32 ± 1 ng·L-1) and the average concentrations obtained in grab samples. The use of passive samplers has advantages over grab samples easier analysis, less time and costs associated with the analytical method. Passive samplers also provide a time-weighted information about the concentration of pollutants in the aquatic environment. However, information may be lost when the concentration of the target compounds in wastewater effluents is low and the passive samplers are deployed for a short time.Recently, charged aerosol detection (CAD), a universal detection technique in liquid chromatography, has been introduced into monographs of the European Pharmacopoeia (Ph. Eur.), which now employs HPLC-UV-CAD for assessing the impurities of the drug vigabatrin. The separation of vigabatrin and its impurities is facilitated by ion pair chromatography (IPC) in the compendial method using tridecafluoroheptanoic acid (TDFHA) as ion-pairing reagent. However, the subsequent detection of the impurities by UV-CAD is considerably impaired due to the substantial amount of ion-pairing reagent applied in the method generating high levels of background noise. In this study, the influence of the mobile phase composition on the background noise of the CAD was evaluated applying response surface methodology. The model’s results indicated that the chain length of the ion-pairing reagent is a predominant factor for noise generation. Thus, an alternative method for the impurity analysis of vigabatrin using mixed-mode chromatography (MMC) instead of IPC was developed.

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