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DISTRIBUTIONS OF TOTAL, INORGANIC AND ORGANIC PHOSPHORUS IN THE SEDIMENTS NEAR THE HUANGHE RIVER ESTUARY 被引量:1
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作者 林荣根 吴景阳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1992年第3期204-214,共11页
For some hundred surface sediment samples from five cores taken in two cruises near the Huanghe River Estuary, total phosphorus (TP (.inorganic phosphorus (IP (and organic phosphorus (OP)were determined.On the average... For some hundred surface sediment samples from five cores taken in two cruises near the Huanghe River Estuary, total phosphorus (TP (.inorganic phosphorus (IP (and organic phosphorus (OP)were determined.On the average, 527×10-6, 455×10~6 and 72×10-6 were found for TP,IP and OP for the surface sediments taken in the two cruises. The distribution of OP and IP was controlled by the sample particle size: OP content increased with the decreasing of the sample particle size, while the maximal value of IP was found in the silt fraction due to the existence of apatite in our samples. Vertical distributions reflected well the channel change of the Huanghe River. Results from the multiple regressions between the three forms of phosphorus and the percentages of different particle size agreed well with the analytical data. 展开更多
关键词 distribution total phosphorus- INORGANIC phosphorus ORGANIC phosphorus SEDIMENTS
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Continuous flow analysis of dissolved total phosphorus in seawater by UVK_(2)S_(2)O_(8) online digestion method 被引量:1
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作者 YUZhigang RAABEThomas +1 位作者 HEMKENGitta BROCKMANNUwe 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第4期637-645,共9页
Several methods for analysis of dissolved total phosphorus in seawater were reviewed. Discussions were focused on UVirradiation and persulphate oxidation methods which are the most popular dissolved organic phosphorus... Several methods for analysis of dissolved total phosphorus in seawater were reviewed. Discussions were focused on UVirradiation and persulphate oxidation methods which are the most popular dissolved organic phosphorus determinationmethods presently. The compounds used for the phosphorus recovery test were categorized into three groups accordingto their chemical structure. It was found that low power UV irradiation can decompose POC or PC bonds efficientlybut may be inefficient for POP bonds. Heating-bath in acid condition is useful for decomposing POP bonds. Usingthe continuous flow analysis system (Auto-analyzer II), UV digestion and heating-bath, series experiments were carriedout based on the above analysis. Eleven model compounds were employed for the phosphorus recovery test and thefactors influencing the decomposition efficiency of dissolved compounds containing phosphorus were clarified. Finally,the optimal design for determination of dissolved total phosphorus in seawater based on the routine continuous flowanalysis system was presented. For the organic mono-phosphate, the recovery is more than 90% and a recovery of33%~51% was obtained for inorganic or organic polyphosphates. Up to now, this is the highest decompositionefficiency for dissolved phosphorus based on the continuous flow analysis system. 展开更多
关键词 dissolved total phosphorus organic phosphorus ultraviolt persulfate potassium continuous flow analysis
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Establishment of a diatom-total phosphorus transfer function for lakes on the Songnen Plain in northeast China 被引量:1
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作者 SUI Fengyang ZANG Shuying +2 位作者 FAN Yawen LU Xinxin HUI Hongkuan 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第6期1771-1786,共16页
To understand the relationship between planktonic diatoms and environmental variables in the lakes on the Songnen Plain,northeast(NE)China,we investigated water quality and planktonic diatoms from 71 sampling points i... To understand the relationship between planktonic diatoms and environmental variables in the lakes on the Songnen Plain,northeast(NE)China,we investigated water quality and planktonic diatoms from 71 sampling points in 27 lakes,based on which Canonical Correspondence Analysis(CCA)was conducted.The result show that planktonic diatoms displayed certain responses to environment gradients,and the total phosphorus(TP)explained the maximum variation of planktonic diatom species among the 15 environmental variables,suggesting that TP was the most important and significant environmental parameter affecting the distribution of diatom species.In addition,we established a diatom-total phosphorus transfer(DTPT)function,of which component 5 of the weighted averaging partial least squares regression(WAPLS)was chosen to and compared with a series of weighted average regression(WA)models and WA-PLS models.According to the jackknifing statistical test,the component 5 of WA-PLS models provided a lower root-mean-square error prediction(RMSEP=0.202)and a higher correlation coefficient between observation and prediction(R^2_Jack=0.759).After deletion of three outliers,the root-mean-square error prediction of the DTPT function was reduced(RMSEP=0.169)while the correlation coefficient between observation and prediction was increased(R^2_Jack=0.823).Therefore,this DTPT function performed better than other regional TP models in the world.However,it remains demanding for expanding the background dataset to improve the prediction ability of the model. 展开更多
关键词 Songnen Plain DIATOM total phosphorus transfer function
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Optical anisotropy of black phosphorus by total internal reflection 被引量:1
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作者 Wei Xin Hao Bo Jiang +7 位作者 Teng Qian Sun Xiao Guang Gao Shao Nan Chen Bo Zhao Jian Jun Yang Zhi Bo Liu Jian Guo Tian Chun Lei Guo 《Nano Materials Science》 CAS 2019年第4期304-309,共6页
Although abundant research on the anisotropy of van der Waals(vd W)materials has been published,we undertake an in-depth study of their optical properties as they have an important guiding role for light control in tw... Although abundant research on the anisotropy of van der Waals(vd W)materials has been published,we undertake an in-depth study of their optical properties as they have an important guiding role for light control in two-dimensional(2D)nanospace.As an example,we study the reflectance of few-layered black phosphorus(BP)in the total internal reflection(TIR)mode in detail.We demonstrate that its optical anisotropy can be changed on a large scale by varying the incident angles,polarization states,and the in-plane rotation angles of the BP samples.Theoretical analysis indicates that the phenomena observed are common to all the atom-thick biaxial crystals,so these conclusions can be widely applied to other anisotropic 2D materials.This research furthers the current understanding of the properties of BP more comprehensively,and provides guidance for developing new optoelectronic applications,especially when BP and other atom-thick biaxial crystals are integrated with TIR devices. 展开更多
关键词 Black phosphorus Optical anisotropy total internal reflection Biaxial crystal
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Effects of Conservation Methods of Water Samples on Determination of Total Phosphorus
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作者 Zhang Yan Wang Dong +4 位作者 Xu Min Xie Yangcun Luo Yueping Tian Yun Luo Fang 《Meteorological and Environmental Research》 CAS 2014年第1期1-3,11,共4页
Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temper... Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temperature and time. The results showed that SS concentration in water and natural sedimentation time had the greatest impact on the determination of total phosphorus, while the influence of methods of adding conserving agent, conservation temperature and time was relatively smaller. TP concentration in water samples conserved irregularly was higher than the standard value due to the existence of SS and microorganisms in water, and the deviation became larger with the increase of SS concentration in water. In addition, quality control measures and matters needing attention during the conservation process of water samples were put forward to improve the accuracy of TP concentration. 展开更多
关键词 Water samples total phosphorus CONSERVATION Quality control China
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Effects of Sediment on the Test of Total Phosphorus in Water
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作者 Yonghong SHUI Yujun WEI +1 位作者 Hongmei MAO Ting LI 《Meteorological and Environmental Research》 CAS 2021年第3期77-80,共4页
Based on previous studies,the effects of the type,content,particle size and state of sediment on the determination of total phosphorus in water are analyzed.The results show that the type of sediment has a certain inf... Based on previous studies,the effects of the type,content,particle size and state of sediment on the determination of total phosphorus in water are analyzed.The results show that the type of sediment has a certain influence on the determination result of total phosphorus,and the influence cannot be ignored.The degree of influence depends on the specific type.Sediment content is negatively correlated with the determination result of total phosphorus in water.That is,the higher the sediment content is,the lower the determination result is.The particle size of sediment is positively correlated with the determination result of total phosphorus in water.That is,the larger the particle size of sediment is,the higher the determination result is.Among the static,semi-suspended and completely suspended states,the sediment in the static state has the least impact on the determination of total phosphorus,and it has the greatest impact on the determination of total phosphorus when it is fully suspended.Therefore,in the analysis and testing process of total phosphorus,attention should be paid to the impact of sediment to improve the authenticity of the test results. 展开更多
关键词 SEDIMENT total phosphorus Influencing factors
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浅水湖泊TP分布的迎风有限元数值模型研究 被引量:3
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作者 马生伟 蔡启铭 《环境科学研究》 EI CAS CSCD 北大核心 1999年第5期56-59,共4页
从控制方程出发,以Galerkin有限元法为基础,结合有限元法的较新改进,推导、建立了一个适合于浅水湖泊TP浓度分布计算的二维迎风有限元的数值模型,并将其应用于太湖。
关键词 总磷 数值模拟 迎风有限元法 太湖 湖泊污染
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LAS对人工快滤系统去除TP的影响
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作者 郭伟 李培军 +1 位作者 李建东 赵天宏 《环境科学与技术》 CAS CSCD 北大核心 2009年第8期31-33,共3页
文章运用人工土柱模拟的方法来研究LAS对人工快滤系统去除TP的影响。研究结果表明,随着污水中LAS浓度(≤100mg/L)的增加,人工快滤系统对TP的去除率表现为逐渐下降。TP的去除率大小为处理Ⅰ>处理Ⅱ>处理Ⅲ>处理Ⅳ。在延长干化... 文章运用人工土柱模拟的方法来研究LAS对人工快滤系统去除TP的影响。研究结果表明,随着污水中LAS浓度(≤100mg/L)的增加,人工快滤系统对TP的去除率表现为逐渐下降。TP的去除率大小为处理Ⅰ>处理Ⅱ>处理Ⅲ>处理Ⅳ。在延长干化时间条件下,TP的去除率增大,并且LAS浓度越大效果越明显。LAS对人工快滤系统中TP的去除有着显著的影响;但合理地控制工艺参数能够实现LAS和TP的有效去除。 展开更多
关键词 人工快速渗滤系统 直链烷基苯磺酸盐 总磷
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TPS based on trilateration for the feed measurement of FAST 被引量:1
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作者 袁卉 Zhu Lichun 《High Technology Letters》 EI CAS 2018年第1期90-94,共5页
Five-hundred-meter Aperture Spherical radio Telescope( FAST) is the largest sensitive single dish radio telescope in the world,in which the control and measurement of the feed is one crucial section of the FAST contro... Five-hundred-meter Aperture Spherical radio Telescope( FAST) is the largest sensitive single dish radio telescope in the world,in which the control and measurement of the feed is one crucial section of the FAST control system. Trilateration is presented to obtain three-dimensional coordinate for tracking feed focus cabin. Every three total stations chase prism movement to be attached on feed focus cabin and the prism position is determined from the measured distances based on the principle of trilateration. Therefore,feed position is determined from three prisms on the focus cabin. This study is to assess the accuracy and reliability of trilateration calculation on tracking focus cabin of FAST. Different arrangement of total stations on trilateration is theoretically studied. Through experiment,the proposed method shows that the accuracy is better than that of the polar coordinate measurement. The average root mean square error is lower than 0. 6 mm,which is found to have high accuracy and reliability. 展开更多
关键词 Five-hundred-meter Aperture Spherical radio Telescope (FAST) TRILATERATION FEED measurement total STATION prism system(tpS) arrangement of total STATION
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Identifying Nonpoint Sources of Phosphorus and Nitrogen: A Case Study of Pollution That Enters a Freshwater Wetland (Laguna Cartagena, Puerto Rico) 被引量:1
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作者 Yashira Marie Sánchez-Colón Fred Charles Schaffner 《Journal of Water Resource and Protection》 2021年第8期588-604,共17页
Point and nonpoint sources of phosphorus (P) and nitrogen (N) can cause reductions in water quality, including eutrophication. Nonpoint pollution represents a special challenge because of dispersed not easily identifi... Point and nonpoint sources of phosphorus (P) and nitrogen (N) can cause reductions in water quality, including eutrophication. Nonpoint pollution represents a special challenge because of dispersed not easily identifiable sources such as the runoff from soil, nutrients, and other chemicals from agricultural fields and residential areas. Laguna Cartagena is a tropical freshwater wetland, situated in southwestern Puerto Rico. It is a eutrophic ecosystem, and its eutrophication is caused by both external nutrient loading and internal, mainly by phosphorus. This wetland has been affected by phosphorus loading from inorganic agricultural fertilizer in this historically oligotrophic wetland system until the end of subsidized fertilizer use and sugar cane cultivation in the late 1990s. This study identifies: 1) nonpoint sources of phosphorus (SRP, Soluble Reactive Phosphorus and TP, Total Phosphorus) and nitrogen (nitrate, nitrite, and ammonia) that enter Laguna Cartagena;and 2) the role of precipitation events on the contributions of phosphorus and nitrogen loading to ecosystems. Herein we assess water samples from five channelized external sources of P and N that enter Laguna Cartagena at two-week intervals from October 2013 through November 2014. Rainfall data were obtained weekly from a rain gauge. Standard methods were used for all chemical analyses. Results showed that the channelized waterways that carry water to the lagoon can be classified as hypereutrophic (>100 μg/L) for TP concentrations and oligotrophic (<200 μg/L) for nitrogen concentrations. Currently agriculture (rice and cattle) is the predominant land use at the nearby University of Puerto Rico (UPR) Lajas Agricultural Experiment Substation, the predominant nonpoint source of nutrient pollution (SRP, TP and ammonia) in the principal channelized water sources to the lagoon. Current nutrient loads are likely derived from fertilizers applied to the Substation’s rice fields, and a high density livestock. The second important cause of external surface water degradation (SRP, TP and ammonia) is the discharge from rural households in the drainage basin that discharge greywater directly to the environment, as indicated by the results from Cerro Alto hills immediately to the north of the lagoon. Precipitation also was associated with SRP, TP and ammonia loads. 展开更多
关键词 Nonpoint Sources Soluble Reactive phosphorus total phosphorus Nitrogen Depleted EUTROPHICATION
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Effects of Phosphorus Concentration on the Treatment of Domestic Wastewater by a Combination of Hydrolytic Acidification and Biological Aerated Filter Filled with Mussel Shells 被引量:1
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作者 Sun Huiling Liu Mei +3 位作者 Chen Qingguo Rong Zhenying Jiang Yu Sun Jingya 《Meteorological and Environmental Research》 CAS 2016年第1期55-58,共4页
The combination of hydrolytic acidification and biological aerated filter (BAF) filled with mussel shells was used to treat domestic wastewater, and the removal rates of chemical oxygen demand (COD), ammonia nitro... The combination of hydrolytic acidification and biological aerated filter (BAF) filled with mussel shells was used to treat domestic wastewater, and the removal rates of chemical oxygen demand (COD), ammonia nitrogen (NH3-N) and total phosphorus (TP) by the system were analyzed under different TP concentrations. When TP concentration ranged from 12.39 to 14.69 mg/L, the removal rate of COD was the best, over 90.92% ; as TP concentration varied from 2.26 to 2.61 mg/L, the removal rates of NH3-N and TP were the best, up to 100.00% and 76.38% respectively. The results show that it is feasible to use mussel shells as the media of BAF, and TP concentration has certain influence on the performance of the system dealing with domestic wastewater. 展开更多
关键词 Mussel shell Biological aerated filter (BAF) Domestic wastewater total phosphorus China
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Effects of Long-term Located Fertilization on Evolution of Available Phosphorus and Phosphorus Pool in Shandong Fluvo-aquic Soil 被引量:1
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作者 yingpeng zhang gang duan +6 位作者 cuiping sun ziwen zhong ming sun yongping jing jiafa luo luji bo yan li 《Agricultural Biotechnology》 CAS 2018年第2期74-80,共7页
This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus( OlsenP),the evolution of soil total phosphorus( TP) and the ratio... This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus( OlsenP),the evolution of soil total phosphorus( TP) and the ratio change of Olsen-P to TP( PAC) by 33-year fertilization experiments in winter wheat-summer maize rotation system in Shandong fluvo-aquic soil. Eight treatments were designed as no fertilization( CK),nitrogen fertilizer( N),nitrogen and phosphate fertilizer( NP),nitrogen and potassium fertilizer( NK),phosphate and potassium fertilizer( PK),nitrogen-phosphate-potassium fertilizer( NPK),reduced NPK fertilizer( N(15) PK),and increased NPK fertilizer( N(25) PK). Meanwhile,eight organic fertilizer-added treatments were designed based on the application of inorganic fertilizer the same as the above ones. The results showed that TP,Olsen-P and PAC of treatments added with organic fertilizer were higher than those without organic fertilizer,and those of the treatments applied with phosphate fertilizer were higher than those of no phosphate fertilizer. With the increase of years,soil P pool decreased due to crop absorption,nutrient loss and morphological transformation and other causes under the treatments of without and only phosphate fertilizer,while remained stable under the treatments added with organic fertilizer. The PAC values were generally lower in fluvo-aquic soil,and it could be improved by the application of organic fertilizer. On the whole,the application of chemical phosphate fertilizer combined with organic fertilizer could improve the phosphorus content in soil and ensure the supply of phosphorus nutrition. This study would provide scientific basis for fertilization management and soil fertility in fluvo-aquic soil. 展开更多
关键词 Long-term located fertilization Fluvo-aquic soil total phosphorus Available phosphorus phosphorus pool Activity coefficientHome
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冠状动脉侧支循环及PCI治疗对CTO患者Tp-e间期、Tp-e/QT比值的影响 被引量:1
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作者 罗进 王延博 +1 位作者 刘鹏 贺琳 《岭南心血管病杂志》 CAS 2022年第5期397-402,共6页
目的探讨冠状动脉侧支循环(coronary collateral circulation,CCC)对冠状动脉慢性完全闭塞病变(chronic total coronary occlusion,CTO)患者Tp-e间期、Tp-e/QT比值的影响,以及经皮冠状动脉介入(percutane⁃ous coronary intervention,PCI... 目的探讨冠状动脉侧支循环(coronary collateral circulation,CCC)对冠状动脉慢性完全闭塞病变(chronic total coronary occlusion,CTO)患者Tp-e间期、Tp-e/QT比值的影响,以及经皮冠状动脉介入(percutane⁃ous coronary intervention,PCI)治疗对CTO患者Tp-e间期、Tp-e/QT比值的影响及临床意义。方法本研究选取邵阳市中心医院心内科2018年7月至2020年12月期间CTO患者共150例。CCC采用Rentrop评分进行分级,将入选患者分为CCC不良组(Rentrop 0级、1级组),CCC良好组(Rentrop 2级、3级组)。测量各组患者心电图中Tp-e间期、Tp-e/QT比值。另从以上研究对象中按是否成功行PCI治疗分为PCI治疗成功组及PCI治疗失败组。观察两组患者PCI治疗前及治疗后心电图中Tp-e间期、Tp-e/QT比值的情况。结果CCC良好组患者Tp-e间期、Tp-e/QT比值低于CCC不良组,差异有统计学意义(P<0.05)。PCI治疗成功组与PCI治疗失败组患者术前临床资料及Tp-e间期、Tp-e/QT比值比较,差异有统计学意义(P<0.05)。PCI治疗成功组患者术后Tp-e间期、Tp-e/QT比值较术前下降,差异有统计学意义(P<0.05)。PCI治疗成功组患者术后Tp-e间期、Tp-e/QT比值低于PCI治疗失败组,差异有统计学意义(P<0.05)。结论CTO患者中,良好的侧支循环形成有利于降低心室跨壁复极离散度指标Tp-e间期、Tp-e/QT比值,更好地恢复CTO患者心肌细胞电生理稳定性;成功的PCI治疗可以减少CTO患者心室复极离散度指标Tp-e间期、Tp-e/QT比值,从而降低室性心律失常发生的风险。 展开更多
关键词 冠状动脉侧支循环 冠状动脉慢性完全闭塞病变 经皮冠状动脉介入治疗 tp-E间期 tp-e/QT比值
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Measuring Quality of Economic Growth Incorporating Environment and Social Welfare:a Total Productivity Approach with an Application on China
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作者 孙燕燕 RAHMAN Sanzidur DAI Changjun 《Journal of Donghua University(English Edition)》 EI CAS 2018年第5期411-417,共7页
By extending the traditional productivity theory,a new concept total productivity( TP) is introduced. Using a directional distance function approach,the concept is applied to measuring economic growth of 8 economic re... By extending the traditional productivity theory,a new concept total productivity( TP) is introduced. Using a directional distance function approach,the concept is applied to measuring economic growth of 8 economic regions of China covering an 18 years period( 1997—2014) and test its convergence. Results showed that TP grew at an average rate of 6. 6% per year led mainly by technical change( 6. 5%). When environmental undesirable outputs are included,the Middle Yellow River,Northwest and Southwest regions of China witnessed higher productivity changes. Results of the convergence analysis revealed that China had made progress in reducing regional imbalance in growth. Inclusion of undesirable output showed that the energy-saving emission reduction policies had speed up the convergence rate of TP and environment oriented productivity. However,China's welfare oriented productivity is still very low. 展开更多
关键词 undesirable OUtpUT directional DISTANCE function total productivity(tp) Malmquist-Luenberger PRODUCTIVITY index quality of ECONOMIC growth
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Salt effect on MUCT system performance of nitrogen and phosphorus removal
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作者 Huining Zhang Zhuowei Zhang +4 位作者 Kewei Jiang Zhili Li Kefeng Zhang Jianqing Ma Yongxing Qian 《Green Energy & Environment》 SCIE CSCD 2021年第5期670-677,共8页
The effect of salinity on biological nitrogen and denitrifying phosphorus removal was investigated in a Modified University of Cape Town(MUCT)system.Removal rates of COD,NH_(4)^(+)-N,NO_(3)^(-)-N,NO_(2)^(-)-N,phosphor... The effect of salinity on biological nitrogen and denitrifying phosphorus removal was investigated in a Modified University of Cape Town(MUCT)system.Removal rates of COD,NH_(4)^(+)-N,NO_(3)^(-)-N,NO_(2)^(-)-N,phosphorus and the sludge characteristics at salt concentrations(0.0,3.2,6.4,11.2 and 16.0 g L^(-1))were analyzed.With the salt concentration increasing,all the COD,NH_(4)^(+)-N,TN and TP removal rates exhibited a trend of decline,and exhibited an initial reduction and subsequent increase at every stage of salt concentration.NH_(4)^(+)-N,TN and TP removal rates were 92.7%,51.5%and 67.2%in 16 g L^(-1) salt concentration,respectively.And they were outperformed the literature reported and acceptable in practical applications.When the salinity of wastewater changed from 0.0 to 16.0 g L^(-1),the biomass yield coefficients increased from 0.0794 to 0.126 g VSS/g COD.Increased salinity had a detrimental effect on phosphorus-accumulating organisms(PAOs)and denitrifying PAOs(DPAOs)(especially DPAOs).Therefore,phosphorus removal gradually depended on PAO.The simultaneous nitrification and denitrification(SND)rate and nitrogen removal rate(including nitrification rate,denitrification rate,and total nitrogen removal rate)gradually decreased with the increased salinity. 展开更多
关键词 Aquaculture wastewater Denitrifying phosphorus removal MUCT process tp SND rate
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NIRS Prediction of SOM,TN and TP in a Meadow in the Sanjiang Plain,China
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作者 Zhao Yi-hang Jiang Jing-wen +5 位作者 Yang Yu-peng Zhang Xiao-meng Meng Ling-dong Ma Ze-wang Hu Yao Yin Xiu-jie 《Journal of Northeast Agricultural University(English Edition)》 CAS 2021年第4期46-55,共10页
The aim of this study was to establish the applicability of near-infrared reflectance spectroscopy(NIRS)as a rapid method for the accurate estimation of nutrient components in agricultural soils.Focusing on the soil o... The aim of this study was to establish the applicability of near-infrared reflectance spectroscopy(NIRS)as a rapid method for the accurate estimation of nutrient components in agricultural soils.Focusing on the soil of the Sanjiang Plain,NIRS was used to predict soil organic matter(SOM),the total nitrogen(TN)and the total phosphorus(TP).A total of 540 samples were collected from the three different depths(180 samples from each depth:0-10,10-20 and 20-30 cm),from 2015 to 2017,from the Sanjiang Plain in Heilongjiang Province,China.From every depth,120 samples were used to construct the calibration set.Other 60 samples were used to check the efficiency of the model.Combining the first-order differentiation with the partial least square(PLS)method,a prediction model was obtained to measure SOM,TN and TP.The correlation coefficient of SOM from 0 to 10 cm was R2=0.9567,from 10 to 20 cm was R2=0.9416,and from 20 to 30 cm was R2=0.9402.The corresponding ratio(standard deviation[SD]/root mean square error of prediction[RMSEP])was>2.96.R2 of TN with the three depths was 0.9154,0.9028 and 0.9024,respectively,all with SD/RMSEP>2.89.Meanwhile,R2 of TP with the three depths was 0.8974,0.8624 and 0.7804,respectively,all with SD/RMSEP>2.50.These results demonstrated that NIRS based on the first-order differentiation and PLS could efficiently predict SOM,TN and TP from different soil depths. 展开更多
关键词 near-infrared reflectance spectroscopy(NIRS) organic matter total nitrogen total phosphorus
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TPS控制系统在三聚氰胺装置的使用要领及安全策略
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作者 郑广增 武喜英 《化肥设计》 CAS 2007年第5期43-45,共3页
介绍了高压法工艺生产三聚氰胺装置的DCS集散控制系统基本结构和TPS系统的特点、构成、配置;分析了TPS系统网络接口模件在生产中出现的问题;提出了TPS系统单个软件安装时系统的安全策略。
关键词 DCS集散控制系统 tpS(total PLANT Solution)系统 构成 安全策略
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Storm phosphorus concentrations and fluxes in artificially drained landscapes of the US Midwest
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作者 Philippe Vidon Hilary Hubbard +1 位作者 Pilar Cuadra Matthew Hennessy 《Agricultural Sciences》 2012年第4期474-485,共12页
This study investigates phosphorus (P) concentrations and fluxes in tile drains, overland flow, and streamflow at a high temporal resolution during 7 spring storms in anagricultural watershed in Indiana, USA. Research... This study investigates phosphorus (P) concentrations and fluxes in tile drains, overland flow, and streamflow at a high temporal resolution during 7 spring storms in anagricultural watershed in Indiana, USA. Research goals include a better understanding of 1) how bulk precipitation and antecedent moisture conditions affect P concentrations and fluxes at the watershed scale;2) how P concentrations and fluxes measured in tile drains translate to the whole watershed scale;3) whether P losses to the stream are significantly affected by overland flow. Results indicate that bulk precipitation and antecedent moisture conditions are not good predictors of SRP or TP losses (either concentration or flux) to the stream. However, along with previously published storm data in this watershed, results indicate a threshold-based behavior whereby SRP and TP fluxes significantly increase with precipitation when bulk precipitation exceeds 4 cm. Although total SRP and TP fluxes are very much driven by flow, SRP and TP fluxes are somewhat limited by the amount of P available for leaching for most storms. On average, SRP fluxes in tile drains are 13% greater than in the stream, and stream SRP fluxes account for 45% of TP fluxes at the watershed scale. Our results indicate that when P is the primary concern, best management practices aimed at reducing P losses via tile drains are likely to have the most effect on P exports at the watershed scale. 展开更多
关键词 total phosphorus Dissolved Reactive phosphorus Scale Precipitation Sub-Surface Drainage EXPORT Rate
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鄱阳湖水位对沉积物磷释放的影响及总磷考核建议 被引量:5
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作者 张洪 薛雪 +3 位作者 郁达伟 魏源送 桂双林 魏志华 《人民长江》 北大核心 2023年第1期46-52,共7页
为探讨干湿交替对湖泊沉积物内源磷释放的影响,结合基础资料和模拟试验,研究了鄱阳湖水位波动及其驱动下沉积物中磷的释放过程,并对湖区总磷(TP)考核提出建议。结果表明:2020~2022年鄱阳湖星子站水位高幅波动,最高水位差分别为15.01,11.... 为探讨干湿交替对湖泊沉积物内源磷释放的影响,结合基础资料和模拟试验,研究了鄱阳湖水位波动及其驱动下沉积物中磷的释放过程,并对湖区总磷(TP)考核提出建议。结果表明:2020~2022年鄱阳湖星子站水位高幅波动,最高水位差分别为15.01,11.42 m和12.69 m,导致水面面积也呈现高度动态性,最低水位时的裸露面积分别达到3433.92,3442.40 km^(2)和3618.36 km^(2),大面积沉积物会经历干湿交替过程;沉积物磷释放模拟试验结果显示,南矶山和青岚湖断面沉积物经历裸露-暴晒-淹水后,淹水初期沉积物TP的平均释放通量分别高达16.67 mg/(m^(2)·d)和13.23 mg/(m^(2)·d);综合考虑鄱阳湖水体中TP组成特征和水位波动的影响,建议湖区国控断面以活性磷酸盐(SRP)或者溶解性总磷(TDP)替代TP作为磷考核指标,并动态调整磷考核标准的阈值,当星子站水位低于11.00 m时以河流标准考核。 展开更多
关键词 沉积物磷释放 总磷考核 水位变化 鄱阳湖
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Regional Distribution of Soil Phosphorus Across Congregation-Grazing Zones of Forage-Based Pastures with Cow-Calf Operations in Florida
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作者 Gilbert C. Sigua Robert O. Myer +4 位作者 Samuel W. Coleman Cheryl Mackowiak Martin Adjei Chad C. Chase Joseph Albano 《Journal of Environmental Protection》 2011年第4期408-417,共10页
The arrangement of supplemental feed, water, shelter, and their concurrent interactions with topographic features may influence the distribution of animals and their simultaneous use of pasture’s resources. The effec... The arrangement of supplemental feed, water, shelter, and their concurrent interactions with topographic features may influence the distribution of animals and their simultaneous use of pasture’s resources. The effects of grazing and/or congregation management that control phosphorus cycling and distribution have not been sufficiently evaluated. The objectives of this study were: 1) to determine whether cattle congregation sites typical on most Florida ranches, repre-sented by water troughs and shaded areas, are more phosphorus-rich and may contribute more soluble phosphorus to surface water run-off and groundwater than other pasture locations;and 2) to assess the regional distribution of Mehlich-1 extractable soil phosphorus (MP) across congregation-grazing zones of forage-based pastures with cow-calf operations in Florida. Soil samples were collected at increasing distance from congregations structures (water troughs and shades) in established (>10 yr), grazed beef cattle pastures located in three Florida regions. Samples were col-lected in the fall and spring of 2005, 2006, and 2007, respectively;following a radial (every 90 degrees) sampling pat-terns away from the center of the congregation structures. Averaged across years, MP and soil phosphorus saturation in the congregation zones were comparable (p ≤ 0.05) with MP values and soil phosphorus saturation in the grazing zones at all three Florida regions. Average MP at all three pasture locations did not exceed the crop requirement threshold of 50 mg P kg–1 and the water quality protection threshold of 150 mg P kg–1, suggesting that congregation zones in beef cattle pastures at all three regions of Florida are not phosphorus-rich. 展开更多
关键词 Beef Cattle CONGREGATION Structures CONGREGATION ZONE GRAZING ZONE total phosphorus phosphorus Saturation Nutrient Management
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