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Advanced Phosphorus Removal and Needs for Recovery by Enhanced Filtration of Municipal Wastewater 预览
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作者 Stig Morling Mattias Feldthusen 《水资源与保护(英文)》 2019年第5期626-637,共12页
The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous fro... The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous from municipal wastewater. This is already an established demand in many countries. However, as P is a limited raw material, this need for a reuse of P will become an example of what now is labelled “cyclic economy”. For instance, a national demand from the German state is already put in force. In this perspective the advanced filtration techniques will play an interesting role, and most possibly a crucial role. Examples are presented from several municipal WWTPs already in operation with a final polishing treatment step based on chemical precipitation and separation of phosphorus. Typical stable discharge P levels are found at these plants at levels < 0.05 to 0.10 ppm. The new demands on phosphorus recovery will also call for modified process concepts for the WWTP;for instance, a refined biological phosphorus removal (EBP) attains more attention and he needed very low discharge levels of P, where the enhanced P-removal will include different smart filtration techniques. 展开更多
关键词 PHOSPHORUS Advanced REMOVAL Chemical PRECIPITATION FILTRATION Techniques REUSE of Purified Water
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Swedish Experience and Excellence in Wastewater Treatment Demonstrated Especially in Phosphorus Removal 预览
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作者 Stig Morling 《水资源与保护(英文)》 2019年第3期333-347,共15页
Water quality protection in Sweden has a more than 80-year history. The needed knowledge has by large been imported. Now, to some extent the development of phosphorus removal technology may be Swedish contribution to ... Water quality protection in Sweden has a more than 80-year history. The needed knowledge has by large been imported. Now, to some extent the development of phosphorus removal technology may be Swedish contribution to advanced knowledge. This paper presents the development in Sweden, mainly a close to 50-year period. Starting in the late 1960s, a standard of <0.5 mg P/l was the normally raised effluent criteria, regardless of the magnitude of the discharge flow. The successive sharpening of the discharge levels has today resulted in a level of 0.2 to 0.3 mg P/l typically. As a matter of fact, even levels of 0.1 to 0.15 mg P/l have been discussed. The period should a large extent demonstrated both improved technologies and a far better efficiency with respect to the use of chemicals and energy. Some important points in this development may be the understanding of the Oxygen Consumption Potential, as well as the identified needs for an improved nitrogen removal. Lately the problems of complex pollution agents and predominantly the remains of pharmaceutical agents have been identified. To illustrate the development during the 50-year period, two examples are presented from the Swedish context. The main conclusion in this paper is that the Swedish history on phosphorus removal illustrates how empirical science in practice sometimes works, including a never-ending need for an open mind and a readiness to take revised and improved knowledge on board. 展开更多
关键词 WASTE Water Treatment PHOSPHORUS Separation Techniques Oxygen CONSUMPTION Potential NITROGEN
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Effect of high Na2O addition on distribution of phosphorus in lowbasicity converter slag
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作者 Chang Su Ning-ning Lv +3 位作者 Jin-xing Yang Liu-shun Wu Hai-chuan Wang Yuan-chi Dong 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第1期42-51,共10页
In order to improve the dephosphorization efficiency of low-basicity converter slag and decrease the consumption of solid CaO,the effect of high Na2O addition(0-15 mass%)on the distribution of P2O5 between solid solut... In order to improve the dephosphorization efficiency of low-basicity converter slag and decrease the consumption of solid CaO,the effect of high Na2O addition(0-15 mass%)on the distribution of P2O5 between solid solution and matrix phase was investigated.The thermodynamic properties of slag samples were calculated by FactSage 7.0 software.Then,the dissolution behavior of phosphorus element from slag was studied.The results show that the mass fraction of 2CaO*SiO2-2CaO*Na2O*P2O5 solid solution increases when the Na2O content is increased in slag.However,the amount of formed solid solution changes little when the Na2O addition is more than 10 mass%.Moreover,the content of Na2O in solid solution would reach saturation when adding 15 mass%Na2O into the slag.With the increase in Na2O content in slag,the distribution ratio of P2O5 between solid solution and matrix phase increases.The values are evidently higher than the results reported in the literature.Meanwhile,the activity of P2O5 in matrix phase and the activity coefficient of P2O5 in solid solution are decreased with increasing the Na2O content in slag.Furthermore,the dissolution ratio of phosphorus in citric acid solution could be improved by adding Na2O into slag,but the increment of dissolution ratio would decrease when the Na2O content exceeds 10 mass%in slag. 展开更多
关键词 NA2O addition-Low-basicity converter slag PHOSPHORUS DISTRIBUTION ratio Thermodynamic property PHOSPHORUS DISSOLUTION behavior
Response of Chinese fir seedlings to low phosphorus stress and analysis of gene expression differences 预览
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作者 Jianhui Li Dingwei Luo +5 位作者 Guifang Ma Licui Jia Jinliang Xu Huahong Huang Zaikang Tong Yong-Quan Lu 《林业研究:英文版》 CAS CSCD 2019年第1期183-192,共10页
Chinese fir(Cunninghamia lanceolata)is an excellent fast-growing timber species occurring in southern China and has significant value in the forestry industry.In order to enhance the phosphorus utilization efficiency ... Chinese fir(Cunninghamia lanceolata)is an excellent fast-growing timber species occurring in southern China and has significant value in the forestry industry.In order to enhance the phosphorus utilization efficiency in Chinese fir,four clones named X6,S3,S39 and FK were used,and low phosphorus(LP)stress experiments were performed to analyze the response of different clones to phosphorus deficiency.According to the results on seedling height,maximum root length,leaf blade aspect ratio,root ratio,malondialdehyde content,acid phosphates activity,proline content,soluble protein level,and chlorophyll a and b levels of the tested clones,compared to the control groups(CK),the phosphorus high efficiency clone X6 was screen out for transcriptome sequencing experiments.De novo RNA-seq was then used to sequence the root transcriptomes of X6 under LP stress and CK,and we then compared the gene expression differences under the two conditions.A total of 3416 SDEGs were obtained by comparing the LP and CK groups,among which 1742 were up-regulated and 1682 were down-regulated.All SDEGs obtained from the LP and CK treated samples were subjected to KEGG annotation and classification.Through classification statistical analysis using WEGO software,607 SDEGs obtained KEGG pathway annotations,which were related to 206 metabolic pathways.In Chinese fir subjected to LP stress,53 SDEGs related with phosphorus metabolism,and phosphate uptake and transport were obtained from our transcriptome data.Based on the phosphorus metabolism pathway obtained by KEGG classification,combined with previously report on gene annotation related with phosphorus metabolism,the enzymes encoded by SDEG related with phosphorus metabolism and their expression pattern were mapped onto phosphorus metabolism pathway. 展开更多
关键词 Chinese FIR Low PHOSPHORUS stress Root TRANSCRIPTOMES SDEG PHOSPHORUS METABOLISM
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磷素非点源污染水质的毒性负荷模型研究 预览
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作者 冯东 《环境科学与管理》 CAS 2019年第8期56-61,共6页
非点源污染已经成为目前中国水质污染的主要污染源。采用AnnAGNPS5.1模型进行磷素非点源污染水质的毒性负荷研究,为水质污染治理和保护提供可靠分析依据。该模型先通过数据输入与编辑模块将磷素非点源污染水质和气象等信息,反馈到污染... 非点源污染已经成为目前中国水质污染的主要污染源。采用AnnAGNPS5.1模型进行磷素非点源污染水质的毒性负荷研究,为水质污染治理和保护提供可靠分析依据。该模型先通过数据输入与编辑模块将磷素非点源污染水质和气象等信息,反馈到污染负荷计算模块中,再依据水文子模型与土壤侵蚀子模型的地表径流量、蒸发量以及土壤侵蚀量等相关参数,建立磷素毒性负荷子模型,采用该模型运算溶解态磷素负荷与颗粒态磷素负荷,通过两种磷素负荷确定非点源水质中的最终磷素毒性负荷,将该负荷结果反馈到数据输出与显示模块中进行结果展示。实验结果表明,该模型可有效检测出非点源污染水质中的磷素浓度,检测十个湖口样本与八个河道样本误差均低于0.04mg·L-1,并且检测用时和能耗低。 展开更多
关键词 磷素 非点源污染 水质 毒性 溶解态磷素
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中国东海陆架海域柱状沉积物对磷的吸附行为
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作者 王贺 路敏 +2 位作者 李苓 刘晓月 曹晓燕 《海洋湖沼通报》 CSCD 北大核心 2019年第4期72-80,共9页
通过研究磷在海洋柱状沉积物上的吸附动力学曲线和吸附等温线,并结合沉积物表面电荷性质以及磷形态分析,考察了我国东部陆架海域沉积物对磷的吸附特征。结果表明,所研究海域沉积物对磷的吸附过程明显分为快慢两段,48h后吸附可达到平衡;... 通过研究磷在海洋柱状沉积物上的吸附动力学曲线和吸附等温线,并结合沉积物表面电荷性质以及磷形态分析,考察了我国东部陆架海域沉积物对磷的吸附特征。结果表明,所研究海域沉积物对磷的吸附过程明显分为快慢两段,48h后吸附可达到平衡;吸附后的磷主要为可交换态磷,吸附过程以物理作用为主;吸附等温线可用Langmuir交叉型模式描述,在磷初始浓度较低时,沉积物对磷存在解吸现象;沉积物对磷吸附参数的垂直分布较为复杂,受自身性质影响较大;盐度增大,沉积物对磷的吸附能力呈下降趋势。 展开更多
关键词 沉积物 吸附 表面电荷 磷形态 盐度
The lithium and sodium storage performances of phosphorus and its hierarchical structure
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作者 Dan Zhao Lihui Zhang +2 位作者 Chengcheng Fu Jinying Zhang Chunming Niu 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第1期1-17,共17页
Recent preparation of black phosphorene and subsequent discovery of its excellent optical and electronic properties have attracted great attenti on,and ren ewed interest to phosphorus.Rece nt researches have indicated... Recent preparation of black phosphorene and subsequent discovery of its excellent optical and electronic properties have attracted great attenti on,and ren ewed interest to phosphorus.Rece nt researches have indicated that phosphorus structures are promisi ng an odes for lithium-ion and sodium-ion batteries.A high theoretical capacity of 2,596 mAh·g^-1 was predicted for phosphorus according to the reaction of 3Li/Na+P→Li3P/Na3P.However,fast capacity degradation is accompanying with most phosphorus structures due to the low electronic conductivity and structural pulverization induced by large volume change in charging and discharging proceses.The electrochemical performances are significantly affected by the hierarchical structural design of phosphorus.A few reviews of phosphorus structures have been reported recent?However,no review about the electrochemical performances of phosphorus structures according to their hierarchical structures has been reported.First of all,phosphrus allotropes along with their structure and fundamental properties are briefly reviewed in this work.Secondly,the studies on lithiation/sodiation mechanism of red/black phosphorus are presented.Thirdly,a summary about the electrochemical performances of red/black phosphorus composites with different hierarchical structures is presented.Furthermore,the,development challenges and future perspectives of phosphorus structures as anodes for LIBs and SIBs are discussed. 展开更多
关键词 LITHIUM ION BATTERIES SODIUM ION BATTERIES PHOSPHORUS COMPOSITES PHOSPHORUS structures review
Current Fertilization Practice and Phosphorus Loading from Soils near Alpine Lakes of Yunnan Province, China 预览
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作者 Ling Zou Kim Falinski +6 位作者 Peifei Zhao Shenchong Li Lin Lu Min Dai Yiping Zhang Russell Yost Jihua Wang 《农业科学(英文)》 2019年第1期1-16,共16页
Phosphorus loss from fertilization is a significant source of pollution to freshwater lakes worldwide. Production of flowers, vegetables, staple food and vineyard in regions surrounding Dianchi, Erhai, Fuxian and Xing... Phosphorus loss from fertilization is a significant source of pollution to freshwater lakes worldwide. Production of flowers, vegetables, staple food and vineyard in regions surrounding Dianchi, Erhai, Fuxian and Xingyun lakes in Yunnan Province is large-scale. Previous studies have shown that annual fertilizer application rates (AFARs) were excessive in these regions. Significant amount of arable land near lakes has been used to build recreational parks with plants that receive less fertilization to reduce P loading. To answer whether rAFARs were associated with specific crops, AFARs of specific land uses were investigated through interviews. To estimate P loading, NaHCO3-P and NaOH-P concentrations were measured in 753 soil samples of selected layers (0 - 5, 5 - 20, 20 - 40 cm) in regions surrounding these lakes. Soil texture, pH, and cation exchange capacity (CEC) were analyzed to characterize soils. P loading was high ranging from 999 to 2094 mg P/kg as measured by NaOH-P, and levels of NaHCO3-P from 18.6 to 92.2 mg P/kg. AFARs to flower (4745 kg/ha), and vegetable (2967 kg/ha) were higher than those applied to staple food (945 kg/ha), and plants in recreation parks (200 kg/ha). The highest NaHCO3-P and NaOH-P concentrations in selected layers were associated with production of flowers, vegetables, and grapes. Although all layers of soils that were used for recreation parks in regions near Dianchi lake contained lower NaHCO3-P, NaOH-P was almost as high as with soils cultivated with flowers probably reflecting historical additions or differences in soil type. Here we show for the first time in local regions that the production of flowers, grapes and vegetables was a critical source contributing to the buildup of both readily available (NaHCO3-P) and reversibly available P (NaOH-P). Build-up of recreational parks with plants that receive less fertilization would be a long-term remediation to reduce P loading of soils in regions near Dianchi lake. 展开更多
关键词 FERTILIZATION PHOSPHORUS CROP LAKE
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Predictability of Ecological Changes in Lake Kinneret 预览
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作者 Gophen Moshe 《生态学期刊(英文)》 2019年第6期183-199,共17页
Several ecological key factors were indicated in the Lake Kinneret ecosystem during 1969-2000: Elevation of the biomass of non-pyrrhophyte-phytoplankton, chlorophyta, cyanobacteria, and diatoms;decline of Peridinium m... Several ecological key factors were indicated in the Lake Kinneret ecosystem during 1969-2000: Elevation of the biomass of non-pyrrhophyte-phytoplankton, chlorophyta, cyanobacteria, and diatoms;decline of Peridinium maximal from 215 - 240 to 175 - 200 ranges (g/m2);decline of zooplankton (herbivore and predator) relative to phytoplankton biomass (g/m2);lower loads of Nitrogen and slightly also phosphorus in the river Jordan discharge;decline of precipitations and lake water level;significant decline of epilimnetic nitrogen and minor changes of phosphorus concentrations initiated decline of N/P mass ratio to the establishment of a significant change of the ecosystem to be modified from P to N limitation. What could be other than essential outcome of future prediction that results of 20 years (1969-2000) of routine and comprehensive monitor carried out in Lake Kinneret initiated? The Lake Kinneret ecosystem dynamics after 2000 justified retroactive post-factum earlier conclusion of appropriate predictability. 展开更多
关键词 Kinneret NITROGEN PHOSPHORUS CYANOBACTERIA ECOSYSTEM STRUCTURE
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饮食磷摄入量与慢性肾脏病患者营养状况和钙磷代谢的相关性
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作者 张家瑛 刘景芳 陈靖 《中华肾脏病杂志》 CAS CSCD 北大核心 2019年第11期801-808,共8页
目的 评估3~5期慢性肾脏病(CKD)非透析患者饮食磷摄入情况,探讨饮食磷摄入量与营养状况、钙磷代谢的相关性.方法 本研究为横断面研究,选取复旦大学附属华山医院慢性肾脏病门诊3~5期CKD非透析患者为研究对象,采集患者3 d饮食日记、人体... 目的 评估3~5期慢性肾脏病(CKD)非透析患者饮食磷摄入情况,探讨饮食磷摄入量与营养状况、钙磷代谢的相关性.方法 本研究为横断面研究,选取复旦大学附属华山医院慢性肾脏病门诊3~5期CKD非透析患者为研究对象,采集患者3 d饮食日记、人体测量学指标、全面主观评定(SGA)量表评分、血生化指标和24 h尿液生化指标.按照饮食磷摄入量中位数(873 mg/d)将患者分为高磷摄入组(≥873 mg/d)和低磷摄入组(<873 mg/d).比较两组患者一般资料、人体测量学指标、SGA量表评分和血尿生化指标的差异.多因素线性回归法分析患者饮食磷摄入量与不同种类食物摄入量的相关性.结果 共纳入118例患者为研究对象,每日能量摄入为(25.48±4.45)kcal/kg,蛋白质摄入量为(0.88±0.22)g/kg,饮食磷摄入量为(862.85±233.02)mg/d.高磷摄入组与低磷摄入组患者在体重指数和SGA评分项目上的差异无统计学意义.男性高磷摄入组患者的腰围、臀围、腰臀比和小腿围明显高于低磷摄入组(均P<0.05);女性患者两组在人体测量学指标上的差异均无统计学意义.高磷摄入组的血全段甲状旁腺素(iPTH)、血钠、血三酰甘油、血RBC计数、血丙氨酸转氨酶、24 h尿尿素氮、24 h尿肌酐、24 h尿磷水平均高于低磷摄入组(均P<0.05).多因素线性回归分析结果显示,禽畜类对饮食磷摄入量的贡献最大,其次为水产类和奶类.结论 3~5期CKD非透析患者每日磷摄入量稍高于推荐摄入量,饮食磷摄入量的增多可能会导致血iPTH和血钠水平的增高,适量控制饮食磷摄入量并不会损害CKD患者的营养状况. 展开更多
关键词 肾功能不全 慢性 营养状况 钙磷代谢
中国市政污泥中磷的含量与形态分布 被引量:1
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作者 王超 刘清伟 +4 位作者 职音 程柳 王宁 李彩丹 毛宇翔 《环境科学》 EI CAS CSCD 北大核心 2019年第4期1922-1930,共9页
于2016年采集了全国46个城市的市政污泥样品,运用SMT法测定了污泥中不同形态磷的含量.结果表明,我国市政污泥中总磷(TP)、无机磷(IP)、非磷灰石态无机磷(NAIP)、磷灰石态无机磷(AP)、有机磷(OP)和生物有效磷(NAIP+OP)的平均含量分别为(1... 于2016年采集了全国46个城市的市政污泥样品,运用SMT法测定了污泥中不同形态磷的含量.结果表明,我国市政污泥中总磷(TP)、无机磷(IP)、非磷灰石态无机磷(NAIP)、磷灰石态无机磷(AP)、有机磷(OP)和生物有效磷(NAIP+OP)的平均含量分别为(17.32±5.13)、(11.71±4.01)、(9.18±3.44)、(3.03±2.74)、(4.54±4.23)和(13.72±4.36)g·kg^-1.其中IP是污泥中磷的主要存在形态,占TP含量的60%以上;NAIP是主要的无机磷形态,占IP含量的66%以上.污泥中生物有效磷占TP含量的比例介于66.8%~96.1%之间,二者呈现极显著正相关关系(r=0.942,P<0.01).市政污泥磷含量和排放量总体上呈现东高西低的空间分布规律.2016年随污泥处置排放入环境的磷达到了1.04×10^5t,其中1.95×10^4t随污泥农用进入土壤,4.69×10^4t进入填埋场,1.47×10^4t进入建筑材料中,2.34×10^4t经垃圾焚烧进入焚烧灰,4.50t被直接倾倒丢弃.与历史数据对比发现,我国市政污泥中总磷的含量呈现先升高、后降低的变化趋势. 展开更多
关键词 市政污泥 形态分布 生物有效磷 污泥处置
Phosphorus migration mechanism between iron and high phosphorus gangue phase at high temperatures
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作者 Lei Guo Jin-tao Gao +1 位作者 Sheng-ping Zhong Zhan-cheng Guo 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第2期113-122,共10页
The phosphorus migration mechanism during melting separation of non-carbon-reduced high phosphorus iron ore was investigated.Firstly,the equilibrium compositions of hydrogen-reduced high phosphorus iron ore at differe... The phosphorus migration mechanism during melting separation of non-carbon-reduced high phosphorus iron ore was investigated.Firstly,the equilibrium compositions of hydrogen-reduced high phosphorus iron ore at different temperatures were simulated by the use of equilibrium composition module of HSC Chemistry software.Then,thermodynamic calculation was verified by the real heat treatment of simulated hydrogen-reduced high phosphorus iron ore with several pure reagents including self-made pure fluorapatite.The iron particles in the simulated samples gathered and grew up during heat treatment.Meanwhile,the hypoeutectic structure of Fe-P with grid shape of high phosphorus phase and circular shape of low phosphorus phase emerged within those iron particles.With the penetration of phosphorus from the periphery into the iron particles,the grid structure became denser and denser.It proves that the elemenlal phosphorus can be reduced from the gangue phase by metallic iron without solid carbon at high temperatures. 展开更多
关键词 MELTING separation FLUORAPATITE THERMODYNAMICS PHOSPHORUS migration High PHOSPHORUS IRON ore
Effect of Turbulence on Phosphorus Release from Estuarine Sediment 预览
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作者 Jinbo Zhao Mengyuan Liu +1 位作者 Li Xu Yingjun Xu 《环境保护(英文)》 2019年第1期39-47,共9页
Phosphorus (P) is an essential element for growth in aquatic ecosystems but the dynamics of phosphorus cycling within catchments is poorly constrained. The aim of this study was therefore to develop analytical tools t... Phosphorus (P) is an essential element for growth in aquatic ecosystems but the dynamics of phosphorus cycling within catchments is poorly constrained. The aim of this study was therefore to develop analytical tools to investigate the release of inorganic and organic phosphorus species in rivers and estuaries during resuspension events such as storm, wind and tidal induced turbulence. To achieve this aim, laboratory simulations using a mini-annular flume coupled with segmented flow analyser detection were performed. To collect SPM (suspended particulate matter), a specially designed specimen box was deployed in the River Tamar (Devon, UK). Inorganic and total phosphorus were determined using segmented flow analyser methods adapted for use with acidified persulfate digests. The segmented flow analyser had a detection limit (3 s.d.) of 0.53 μg P L-1 for inorganic P and 1.5 μg P L-1 for total P. The mini-annular flume provides a suitable method for laboratory simulations, e.g. we managed to get low blanks and good experimental reproducibility, and are also able to see changes in P species within analytical precision. Results showed that increase of shear stress (or SPM) caused release of inorganic P from sediment. This could be used as a fact to build a model to study P dynamics during resuspension events in the river and estuaries environment. 展开更多
关键词 PHOSPHORUS Sediment-Water INTERFACE TRANSFORMATION
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三峡消落带落羽杉人工幼林叶片分解及磷释放特征 预览
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作者 宋虹 袁中勋 +3 位作者 任庆水 杨文航 王朝英 李昌晓 《生态学报》 CAS CSCD 北大核心 2019年第21期8100-8110,共11页
为探究三峡消落带人工重建植被落羽杉(Taxodium distichum)幼林叶片在不同水文条件下的分解特征及其对土壤⁃水体磷的贡献潜力,本实验在控制条件下,模拟三峡库区消落带土壤水分变化设置了常规生长水分条件(CK)、轻度干旱水分胁迫(T1)、潮... 为探究三峡消落带人工重建植被落羽杉(Taxodium distichum)幼林叶片在不同水文条件下的分解特征及其对土壤⁃水体磷的贡献潜力,本实验在控制条件下,模拟三峡库区消落带土壤水分变化设置了常规生长水分条件(CK)、轻度干旱水分胁迫(T1)、潮湿(T2)、2 cm水淹(T3)、10 cm水淹(T4)5个不同处理,研究落羽杉叶片分解及磷释放特征。研究结果表明:(1)在整个试验期间(90 d),T3、T4两个水淹处理的叶片失重率分别达51%(T3)和55%(T4),显著高于CK、T1、T2三个未水淹处理;(2)未分解残留叶片中的全磷含量在CK、T1、T2三个未水淹的处理组呈现增加趋势,而水淹处理(T3、T4)呈减少趋势;(3)土壤全磷含量在试验过程中呈现波动性变化特征,但至试验结束时,各处理中土壤全磷含量与CK相比均无显著差异;(4)T3、T4处理中叶片添加显著增加了上覆水体中总磷含量,试验过程中呈现出在分解初期迅速上升,在分解10 d时达到峰值,之后逐渐降低并趋于稳定,但试验结束时仍显著较高,分别是对应无叶片组的17.15倍(T3)和5.81倍(T4)。这些结果说明水淹通过促进落羽杉叶片的分解从而增加上覆水体中磷的含量,因此有必要在水淹前对消落带的落羽杉幼林叶片进行适时采收,以尽可能减少其对库区水体的磷负荷。 展开更多
关键词 消落带 土壤水分变化 落羽杉叶片 三峡库区
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畜禽粪便中磷素特征及在农田生态系统中的转化利用 预览
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作者 王春雪 王昭 +3 位作者 陈建军 李博 祖艳群 李元 《楚雄师范学院学报》 2019年第3期91-100,共10页
畜禽粪便中含有大量的植物所需的营养元素,其中的磷素含量及组分存在极大差异,因此,了解不同畜禽粪便中的磷素特征,在资源化利用畜禽粪便中的磷素、提高其植物利用率、有效控制其流失中具有重要意义。本文重点综述了我国不同种类的畜禽... 畜禽粪便中含有大量的植物所需的营养元素,其中的磷素含量及组分存在极大差异,因此,了解不同畜禽粪便中的磷素特征,在资源化利用畜禽粪便中的磷素、提高其植物利用率、有效控制其流失中具有重要意义。本文重点综述了我国不同种类的畜禽粪便磷素组成不同,同时概述了磷素在农田系统中的循环路径,分析了土壤酶活性、微生物种类、作物类群等因素对农田土壤中磷素转化利用的影响,并提出了利用畜禽粪便要从其还田入手,综合考虑不同畜禽粪便的养分含量,利用合适的土壤磷素活化剂,以达到农业、生态、环境各方面平衡的利用效果。尤其是土壤酶及解磷微生物,利用微生物群落的互作来全面提升畜禽粪便中P素的利用效率,使畜禽粪便中的P真正进入到农田系统中进行循环,是今后的研究方向。 展开更多
关键词 畜禽粪便 生态效应 转化 利用 作物-土壤系统
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太湖蓝藻水华暴发机制与控制对策 预览 被引量:2
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作者 杨柳燕 杨欣妍 +2 位作者 任丽曼 钱新 肖琳 《湖泊科学》 EI CAS CSCD 北大核心 2019年第1期18-27,共10页
湖泊蓝藻水华暴发由于引发水生态系统的灾害和饮用水安全风险而成为国内外研究的热点之一.太湖蓝藻水华暴发原因多样,其中蓝藻自身的特性是水华暴发的内因,太湖的地理、水文和气象特征为蓝藻水华暴发提供了合适的温度和水动力条件,是蓝... 湖泊蓝藻水华暴发由于引发水生态系统的灾害和饮用水安全风险而成为国内外研究的热点之一.太湖蓝藻水华暴发原因多样,其中蓝藻自身的特性是水华暴发的内因,太湖的地理、水文和气象特征为蓝藻水华暴发提供了合适的温度和水动力条件,是蓝藻水华暴发的外因,湖泊草-藻型生态系统的转变以及氮、磷营养盐的高负荷输入更利于蓝藻生长,湖泊氮、磷营养盐四重循环是蓝藻水华不断暴发的维持机制,蓝藻水华暴发与氮、磷营养盐浓度之间存在交互作用关系.太湖蓝藻水华的控制应以陆源控源截污为基础,增加湖泊营养盐输出为重点,实现疏堵有机结合,其中恢复水生植被,重建草-藻结合型水生态系统是太湖湖泊生态修复的关键所在. 展开更多
关键词 太湖 蓝藻水华 暴发机制
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磷元素对汽车内饰用模具硅橡胶硫化行为的影响 预览
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作者 潘鸽 王晓伟 +8 位作者 李双双 付志磊 刘芳 马蕊 许东华 姚卫国 窦艳丽 管东波 石彤非 《有机硅材料》 CAS 2019年第6期435-440,共6页
针对汽车内饰用模具硅橡胶出现的硫化不充分问题,通过向双组分室温硫化(RTV-2)加成型液体硅橡胶中加入一定量的三(2,4-二叔丁基苯基)亚磷酸酯与磷酸三苯酯,研究了不同价态磷(P)元素对硅橡胶硫化行为的影响以及引起铂催化剂中毒的临界P... 针对汽车内饰用模具硅橡胶出现的硫化不充分问题,通过向双组分室温硫化(RTV-2)加成型液体硅橡胶中加入一定量的三(2,4-二叔丁基苯基)亚磷酸酯与磷酸三苯酯,研究了不同价态磷(P)元素对硅橡胶硫化行为的影响以及引起铂催化剂中毒的临界P元素含量.结果表明,聚氯乙烯(PVC)表皮中引起硅橡胶不完全硫化的主要因素为不饱和态的P元素.不饱和态P元素轨道上的共享电子对会与铂结合,发生不可逆反应,引起铂催化剂中毒,从而导致RTV-2硅橡胶无法完全硫化.在实际生产中,需保证PVC表皮中不饱和P元素含量小于导致铂催化剂中铂元素中毒的临界值,RTV-2硅橡胶方可完全硫化,复制出清晰的PVC表皮花纹. 展开更多
关键词 磷元素 加成型硅橡胶 铂催化剂 流变 花纹
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云南省文山州新鲜三七中钾、磷含量分布调查
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作者 宋妮泽 徐丹先 《食品安全质量检测学报》 CAS 2019年第20期6991-6996,共6页
目的调查云南省文山州新鲜三丂花、根、茎、叶中钾和磷含量皀分布情况。方法按照GB 5009.268-2016《食品安全国家标准食品中多元素皀测定》中电感耦合等离子体发射光谱法对随机采集皀文山州出产新鲜三丂花、根、茎和叶各40仹样品中皀钾... 目的调查云南省文山州新鲜三丂花、根、茎、叶中钾和磷含量皀分布情况。方法按照GB 5009.268-2016《食品安全国家标准食品中多元素皀测定》中电感耦合等离子体发射光谱法对随机采集皀文山州出产新鲜三丂花、根、茎和叶各40仹样品中皀钾、磷含量进行测定,使用SPSS软件对数据进行分析。结果 160件样品中钾含量范围为64.98~2307.84mg/100g,其中花、根、茎、叶中钾含量分别为948.05mg/100 g、282.65 mg/100 g、334.51 mg/100 g、517.42 mg/100 g;磷含量范围为21.05~951.70 mg/100 g,其中花、根、茎、叶中磷含量分别为355.17 mg/100 g、94.33 mg/100 g、61.86 mg/100 g、74.47 mg/100 g。结论云南省文山州新鲜三丂中钾含量由高到低依次为花、叶、茎、根,磷含量由高到低依次为花、根、叶、茎,三丂花皀钾含量和磷含量都远高于其他部位,在文山州8个地区中,马关县产三丂中钾含量和磷含量较高,广南县产三丂中钾含量和磷含量较低。 展开更多
关键词 三七 电感耦合等离子体发射光谱法
腾冲红花油茶营养器官主要矿质元素含量年内变化分析 预览
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作者 谢胤 曹永庆 +5 位作者 余祖华 尹必期 王自洪 徐志映 寸明辉 任华东 《西部林业科学》 CAS 北大核心 2019年第3期97-103,共7页
以腾冲红花油茶实生40a纯林为对象,研究腾冲红花油茶叶片、枝干和根系中的氮、磷、钾、镁元素含量的年内变化规律。结果表明,腾冲红花油茶营养器官的氮、磷、钾、镁元素含量比例约为9︰1︰4︰1,各元素在叶片中的含量较高,根系中的含量... 以腾冲红花油茶实生40a纯林为对象,研究腾冲红花油茶叶片、枝干和根系中的氮、磷、钾、镁元素含量的年内变化规律。结果表明,腾冲红花油茶营养器官的氮、磷、钾、镁元素含量比例约为9︰1︰4︰1,各元素在叶片中的含量较高,根系中的含量较低。此外,各营养器官的氮、磷、钾、镁元素含量的年内变化规律不同,叶片和枝干中氮、磷、钾、镁元素含量总体上表现出'下降-上升-下降'的变化趋势,而根系中的氮、磷、镁元素含量则表现出'上升-下降-上升'的变化趋势。从1月份至3、4月份,叶片和枝干中氮、磷、钾、镁元素的含量逐渐下降,5月份各元素的含量显著升高。与叶片和枝干不同,根系中磷和镁元素在1-4月表现出明显上升趋势,而氮和钾元素含量变化不明显,5-8月,各元素表现出下降趋势。由此可知,腾冲红花油茶冬季施肥应注重磷、镁元素的施用,4月份春季追施复合肥,氮、磷、钾元素比例宜控制在9︰1︰4。 展开更多
关键词 腾冲红花油茶 营养器官
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不同年限温室土壤磷素变化分析
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作者 张敬敏 赵娜 +2 位作者 魏珉 赵利华 隋申利 《土壤通报》 CAS CSCD 北大核心 2019年第3期597-601,共5页
温室大量施肥引起土壤磷素水平极高,为明确温室土壤磷素变化特点,以露地土壤为CK,选择种植模式相近、种植年限不同的温室土壤,通过相关分析和通径分析,阐明各形态磷素变化特点及其与有效磷的关系。结果表明:土壤各形态磷素均随种植年限... 温室大量施肥引起土壤磷素水平极高,为明确温室土壤磷素变化特点,以露地土壤为CK,选择种植模式相近、种植年限不同的温室土壤,通过相关分析和通径分析,阐明各形态磷素变化特点及其与有效磷的关系。结果表明:土壤各形态磷素均随种植年限的延长而增加,以Ca8-P和Ca10-P的含量最高。各年限温室土壤Ca2-P、Ca8-P和Al-P均显著高于露地CK,第10年和第14年无显著差异;温室土壤Ca10-P和O-P只在第14年时与CK有显著差异。同年限温室间的极差随年限延长而逐渐加大。温室土壤有效磷、全磷和无机磷总量均显著高于CK,有效磷第10年最高达420.00 mg kg^-1,无机磷占全磷的百分比保持相对稳定。相关分析和通径分析表明,Ca2-P和Ca8-P对土壤有效磷的直接影响和综合影响均呈正相关,而A1-P和Fe-P对有效磷综合影响呈正相关,但直接影响为负相关,这可能与温室土壤pH降低使Fe和Al大量溶解而和磷发生沉淀反应有关。 展开更多
关键词 温室土壤 磷素 相关分析 通径分析
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