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951.
拖网及深海摄像站位位置与水深的初步校正   总被引:1,自引:0,他引:1  
对在海山富钴结壳调查中拖网取样和深海摄像调查的站位位置和水深的校正方法进行了研究,对其钢缆角度(θ角)等关键参数的选取以及水深校正可靠性的评估进行了分析和讨论,同时还利用MM3海山站位的数据进行了拖网和摄像站位的位置和水深校正,并对其可靠性进行了评估.结果表明:对于拖网站位,对应I至Ⅲ级海况,钢缆θ角分别被确定为15°、20°和25°时,其站位位置和水深校正误差最小,个别存在着较大误差的站位,需通过虚拟水深的验证进行手动校正,以保证校正后数据的可信性;对于摄像站位,当钢缆θ角被确定为25°左右时,虚拟水深和实际校正水深间在±50 m的允许误差范围(此为多波束的允许误差)内时,测站的站位位置和水深校正的效果较好,有超过50%的摄像测站的校正水深在误差允许的范围内.可见该校正方法具有较高的可信度,可基本满足富钴结壳的资源量评估和矿床圈定工作的需要.  相似文献   
952.
方士鑫  李宪璀 《海洋科学》2020,44(3):138-145
高吸水性树脂(Superabsorbent polymers,SAPs)是一种具有优良吸水能力和保水能力的功能高分子材料,因其良好的性能被应用于止血材料、个人卫生产品、干旱地区的农业及林业保水剂、污水处理剂以及生物材料等方面。以天然多糖原料制备新型高吸水性树脂是目前的研究热点之一。本文综述了近年来以海洋生物多糖-壳聚糖为原料制备高吸水性树脂的方法,以及壳聚糖基高吸水性树脂在应用方面的研究进展,并对壳聚糖基高吸水性树脂未来的发展趋势进行了展望。  相似文献   
953.
The integrated steel industry is considered as one of the important industrial sectors, and its outputs are inputs for other sectors including construction, engineering, medical and scientific equipment, and defence. Massive production, consumption, and export of steel signify a country's economic index. This review outlines the World's steel production quantities, the processes involved, and wastewater generation from the industry and its treatment. Wastewater generated from steel plants is highly complex and requires intensive treatment before discharge into natural water bodies. Technologies adopted for treating wastewater generated from steel industries are deliberated, focusing on coking wastewater treatment. Microbial mediated processes provide an effective means of degrading the contaminants, but the toxicity of certain compounds during higher pollutant load inhibits its further treatment. However, these processes can be integrated with either electrochemical technologies or advanced oxidation processes (AOPs), which can reduce the toxicity level. Hence, when a highly concentrated and complex mixture of contaminants is considered, an integrated approach is a resourceful option in terms of cost-effectiveness and treatment efficiency.  相似文献   
954.
A single bioaugmentation reactor and a side-stream gaslift membrane bioreactor combined with bioaugmentation are conducted to treat real wastewater from a centralized piggery slaughterhouse in Vietnam. The bioaugmented reactor is inoculated with heterotrophic microorganisms (Bacillus sp.) isolated from piggery slaughterhouse wastewater. The results of a single bioaugmentation experiment show high removal efficiency of chemical oxygen demand (COD) (84.8%–97.5%) and total nitrogen (TN) (69.9%–87.2%) at loading rates of 1.28–3.89 and 0.14–0.37 kg m−3 d−1, respectively. The combined system demonstrates a significantly higher TN removal efficiency (89.0%–96.1%) (p < 0.001), more stable flux (36.0–38.4 L m−2 h−1), and transmembrane pressure (0.95–1.05 bar), and better capacity of separation of solid–liquid phases compared to the single bioaugmentation. High COD and TN removal efficiency is possibly due to assimilation and simultaneous nitrification and denitrification processes. The results of this study also indicate the feasibility and propitious efficiency of the bioaugmented gaslift membrane bioreactor for piggery slaughterhouse wastewater treatment.  相似文献   
955.
The presence of trace antibiotics in domestic and industrial effluents poses a risk of toxicity to fauna and flora. The application of floating treatment wetlands (FTWs) is a low-cost and sustainable approach to remediate wastewater. In this study, the performance of different macrophytes vegetated in FTWs for the remediation of ciprofloxacin (CIP)-contaminated water is investigated. Six macrophytes, Brachia mutica, Typha domingensis, Phragmites australis, Canna indica, Cyperus laevigatus, and Leptochloa fusca, are vegetated in FTWs for the removal of CIP (50 mg L−1) from water. The FTWs show the potential to remove 30–43.58 mg L−1 CIP from water in 28 days. They also reduce the chemical oxygen demand (118–138 mg L−1) and biochemical oxygen demand (35–45 mg L−1) of water. Among the macrophytes, C. indica removes maximum (43.58 mg L−1) and T. domingensis minimum (30 mg L−1) CIP. Canna indica and T. domingensis exhibit the maximum and minimum increase (30% and 12% of dry biomass) in growth, respectively. This study reveals that the FTWs vegetated with different plant species exhibit varying performances in removing CIP from water. This investigation is a step forward toward sustainable bioremediation of water contaminated with antibiotics.  相似文献   
956.
Wastewater from industries causes major environmental pollution problems. The urban development and commercialization in developing countries cause deterioration of surface water resources. Hence, for its improvement, it is essential to develop highly sensitive devices with quick response for monitoring of wastewater contamination. In this respect, biotechnological processes such as biosensors can be promising and a robust option for detection of toxic pollutants. Biosensors can be applied in order to acquire real-time quantitative data. Nowadays, the enzymes or whole cell bio-reporters-based biosensors have promising potential due to the possibility of miniaturization and opportunity for development of in situ biosensors. The growing need of convenient, rapid, and efficient biosensing devices explains the current advancement of biosensors with new transduction materials for multiplexed contaminant detection. Considering the extensive range of sensing strategies including immunochemical-based, enzymatic and nonenzymatic signals, different kinds of biosensors can be classified as electrochemical, optical, thermal, etc. For the past few years, more attention has been paid to nanomaterial-based biosensors which exhibit monitoring on the basis of chemical reactions and biological phenomena. Overall, this review focuses on principle and operation (transduction mechanism) of biosensors based on bio-recognition elements, for the early detection of organic and inorganic contaminants existing in wastewater.  相似文献   
957.
南京煦园太平湖富营养化及其防治   总被引:23,自引:0,他引:23  
公园小水体的富营养化严重影响了观赏价值,这在国内是普遍存在的问题,为改变这种状态,作者于1994年对南京煦园内太平湖的水质进行了理化和生物指标的监测,并采取了水培经济植物的生态工程的治理措施,收到了较好效果。  相似文献   
958.
太湖上游流域经济发展对废水排放及入湖总磷的影响   总被引:5,自引:3,他引:2  
吴攀  秦伯强  于革  周健  周莉 《湖泊科学》2015,27(6):1107-1114
为探索太湖流域水环境质量随经济发展的变化趋势,利用环境库兹涅茨曲线模型模拟1978-2012年太湖上游流域人均GDP与废水排放量、入湖总磷负荷的关系.结果表明:以1978年为计算基期,太湖上游流域人均GDP年均增速为10.3%~11.8%;1990-2012年,太湖上游流域年均工业废水排放量和废水排放总量分别为64799×104、93707×104t,与人均GDP均呈倒U型关系,从2006-2007年、2008-2009年呈下降趋势;入湖总磷负荷与太湖上游流域废水排放总量呈显著正相关,且与人均GDP呈倒U型关系,从2007-2008年呈下降趋势,在1990s以前为850~1200 t/a,1990s以后为1300~2000 t/a.该研究为从经济学角度评估太湖上游流域废水排放、入湖总磷负荷及其变化趋势提供科学依据.  相似文献   
959.
960.
Constructed wetlands are often used for advanced treatment of the secondary effluent of municipal wastewater treatment plants (WWTPs). Through assessing wetlands based on economic, technical, environmental, and social impacts, an optimal process is selected. In this study, a set of assessment methods for wetland treatment technology is established: The analytic hierarchy process (AHP) is used to establish the evaluation index system; the entropy weight method is employed to calculate the index weights; and the preference ranking organization method for enrichment evaluation (PROMETHEE) is utilized for ranking of the selected treatment technologies. Then four processes applied in Taihu Lake basin, China are evaluated. The results show the following ranking: Vertical‐flow wetland–ecological pond–surface‐flow wetland–horizontal‐flow wetland, vertical‐flow wetland–horizontal‐flow wetland, ecological pond–horizontal‐flow wetland–surface‐flow wetland, and ecological ditch–ecological pond. The wetland exhibits certain universality and space portability with regard to treatment of municipal WWTP effluent. From the view of comprehensive benefits, the ranking of the treatment technology based on the vertical‐flow wetland is high (Φ values between 0.0224 and 0.0349), whereas that based on the ecological pond is low (Φ values between ?0.2086 and ?0.2652), owing to the mechanism of the process itself and the role of microorganisms in the system. Moreover, for organic matter removal, a vertical‐flow wetland process is recommended (48%), whereas for the removal of N contamination, an integrated‐flow wetland process is suggested (31.2% for NH3‐N, 32.4% for TN removals).  相似文献   
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