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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
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
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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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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太湖蓝藻水华暴发机制与控制对策 预览 被引量:1
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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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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
Spatial Distribution Characteristics of Nitrogen and Phosphorus in Sediments of Coastal Wetlands 预览
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作者 Huanqiang ZHENG Kun RONG 《亚洲农业研究:英文版》 2019年第1期42-46,共5页
Taking the typical coastal wetlands in the Yellow River Delta as the research object,(i)three parallel strips A1,A2 and A3 were set up along the vertical coastline in the newborn wetland at 60 km south of the Dongwenl... Taking the typical coastal wetlands in the Yellow River Delta as the research object,(i)three parallel strips A1,A2 and A3 were set up along the vertical coastline in the newborn wetland at 60 km south of the Dongwenliu Management Station in the Yellow River Delta Nature Reserve.(ii)Sample plots B(Phragmites communis area),C(Suaeda glauca area),and D(Tamarix chinensis area)were set up near the field ecological station of the coastal wetlands.Through collecting sediment samples and measuring nitrogen and phosphorus contents,the spatial distribution characteristics of nitrogen and phosphorus in sediments of coastal wetlands were studied.Following results were obtained.(i)The concentration of TN in the 0-20 cm surface sediments of the coastal wetlands in the Yellow River Delta was in the range of 130-695 mg/kg,the concentration of TP was in the range of 589-778 mg/kg,and the average content of TN and TP was 372.18 and 660.82 mg/kg respectively.(ii)From the remote coastal area of the Yellow River to the near coastal area,the horizontal distribution of TN in the sediments was different at each level,and the TN content in the surface sediments gradually decreased;the content of TP generally increased.(iii)At the profile level,the content of TN and TP generally showed a trend of decreasing gradually from the surface layer and tending to be stable,and the peak appeared at the outermost layer.(iv)In the sediments under different vegetation cover,TN was more evenly distributed on each profile,and the distribution of TP on each profile was different.TN showed the largest distribution in the 0-20 cm surface sediments in the T.chinensis area,while TP had the largest distribution in the 80-100 cm bottom sediments in the T.chinensis area. 展开更多
关键词 COASTAL WETLAND SEDIMENT NITROGEN PHOSPHORUS Spatial distribution
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Q235B棒材的加工质量问题及控制措施 预览
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作者 邓再兴 《天津冶金》 CAS 2019年第A01期21-24,共4页
在用户使用Q235B棒材过程中,出现了不同的加工质量问题。采用金相显微镜对金相组织和夹杂物进行分析,并检测了试样的化学成分。结果表明,产生加工质量问题的原因主要是目前生产的钢中B类夹杂物超标、P元素含量波动范围大并超出要求上限... 在用户使用Q235B棒材过程中,出现了不同的加工质量问题。采用金相显微镜对金相组织和夹杂物进行分析,并检测了试样的化学成分。结果表明,产生加工质量问题的原因主要是目前生产的钢中B类夹杂物超标、P元素含量波动范围大并超出要求上限、连铸过程中脱方等现象。对此提出了相应的控制措施,为提高产品质量提供了指导。 展开更多
关键词 棒材 加工 质量 夹杂物 P元素 脱方
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Family-level leaf nitrogen and phosphorus stoichiometry of global terrestrial plants
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作者 Di Tian Zhengbing Yan +11 位作者 Suhui Ma Yuehong Ding Yongkai Luo Yahan Chen Enzai Du Wenxuan Han Emoke Dalma Kovacs Haihua Shen Huifeng Hu Jens Kattge Bernhard Schmid Jingyun Fang 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第8期1047-1057,共11页
Leaf nitrogen(N) and phosphorus(P) concentrations are critical for photosynthesis, growth, reproduction and other ecological processes of plants. Previous studies on large-scale biogeographic patterns of leaf N and P ... Leaf nitrogen(N) and phosphorus(P) concentrations are critical for photosynthesis, growth, reproduction and other ecological processes of plants. Previous studies on large-scale biogeographic patterns of leaf N and P stoichiometric relationships were mostly conducted using data pooled across taxa, while family/genus-level analyses are rarely reported. Here, we examined global patterns of family-specific leaf N and P stoichiometry using a global data set of 12,716 paired leaf N and P records which includes 204 families, 1,305 genera, and 3,420 species. After determining the minimum size of samples(i.e., 35 records), we analyzed leaf N and P concentrations, N:P ratios and N~P scaling relationships of plants for 62 families with 11,440 records. The numeric values of leaf N and P stoichiometry varied significantly across families and showed diverse trends along gradients of mean annual temperature(MAT) and mean annual precipitation(MAP). The leaf N and P concentrations and N:P ratios of 62 families ranged from 6.11 to 30.30 mg g–1, 0.27 to 2.17 mg g–1, and 10.20 to 35.40, respectively. Approximately 1/3–1/2 of the families(22–35 of 62) showed a decrease in leaf N and P concentrations and N:P ratios with increasing MAT or MAP, while the remainder either did not show a significant trend or presented the opposite pattern. Family-specific leaf N~P scaling exponents did not converge to a certain empirical value, with a range of 0.307–0.991 for 54 out of 62 families which indicated a significant N~P scaling relationship. Our results for the first time revealed large variation in the family-level leaf N and P stoichiometry of global terrestrial plants and that the stoichiometric relationships for at least one-third of the families were not consistent with the global trends reported previously. The numeric values of the family-specific leaf N and P stoichiometry documented in the current study provide critical synthetic parameters for biogeographic modeling and for further studies on the physiological and ecologica 展开更多
关键词 LEAF nitrogen (N) LEAF phosphorus (P) plant STOICHIOMETRY FAMILY N:P ratios N~P SCALING relationship climate
镧改性介孔材料对砷、磷的吸附
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作者 张海婷 张永敏 +1 位作者 王天慧 王萍 《环境工程学报》 CAS CSCD 北大核心 2019年第8期1791-1799,共9页
为探究在复合污染条件下介孔吸附材料对砷、磷的去除效果,通过水热合成法制备镧金属改性介孔吸附材料(La-MCM-41),采用X-射线衍射(XRD)、比表面积测定(BET)、扫描电镜(SEM)等分析方法对改性前后的介孔吸附剂进行了表征;研究了介孔吸附... 为探究在复合污染条件下介孔吸附材料对砷、磷的去除效果,通过水热合成法制备镧金属改性介孔吸附材料(La-MCM-41),采用X-射线衍射(XRD)、比表面积测定(BET)、扫描电镜(SEM)等分析方法对改性前后的介孔吸附剂进行了表征;研究了介孔吸附剂在不同吸附体系中对砷、磷的降解效果、等温线及动力学。结果表明:La-MCM-41仍具有长程有序的六方相介孔结构,BET比表面积、总孔容均减小,平均孔径有所增加;介孔吸附剂在单独吸附体系下对砷、磷的吸附量大于同步吸附体系,且均符合二级反应动力学。通过分析可知,在2种体系下,改性后的介孔吸附剂极大地提高了对砷、磷的吸附量,是一种经济高效的吸附材料。 展开更多
关键词 介孔材料 同步吸附
不同钾水平下厚皮甜瓜生育后期氮磷钾吸收及利用特征 预览
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作者 王小娟 陈健晓 +5 位作者 伍壮生 李雪峤 张文 吴月燕 廖道龙 高芳华 《热带作物学报》 CSCD 北大核心 2019年第6期1046-1054,共9页
以‘翠甜’厚皮甜瓜为试材,采用盆栽砂培试验,设6个钾水平,即K1~K6(0、3、6、9、12、15mmol/L),研究其对厚皮甜瓜生育后期氮、磷、钾养分吸收与利用的影响。结果表明:施钾能够降低厚皮甜瓜各器官氮含量及成熟期根、茎叶氮累积量,显著增... 以‘翠甜’厚皮甜瓜为试材,采用盆栽砂培试验,设6个钾水平,即K1~K6(0、3、6、9、12、15mmol/L),研究其对厚皮甜瓜生育后期氮、磷、钾养分吸收与利用的影响。结果表明:施钾能够降低厚皮甜瓜各器官氮含量及成熟期根、茎叶氮累积量,显著增加果实氮累积量;增加根、果实磷含量及各器官磷累积量,显著增加果实、单株磷累积量;增加各器官钾含量及钾累积量,显著增加茎叶、果实以及单株钾累积量;显著增加氮生理利用效率和磷收获指数,增加氮收获指数,显著降低钾收获指数和磷、钾生理利用效率;单果鲜重以K2、K3和K4处理较高,且处理间差异不显著。钾处理与其厚皮甜瓜各器官氮、磷、钾含量存在的显著相关关系与器官部位及生育期有关,但与氮含量均呈显著负相关,与钾含量均呈显著正相关;各器官氮磷钾含量与氮收获指数没有显著相关性,但茎叶氮累积量与氮收获指数呈显著负相关;茎叶氮累积量与磷收获指数呈极显著负相关,果实磷、钾含量及累积量均与磷收获指数呈显著或极显著正相关;根、果实氮含量与钾收获指数呈极显著正相关,根磷含量与钾收获指数呈显著负相关,茎叶及果实钾含量和累积量均与钾收获指数呈极显著负相关。通过比较拟合优度(决定系数R2),发现钾水平与成熟期茎叶磷含量采用二次多项式拟合最佳,钾水平与成熟期根钾含量采用线性拟合最佳,钾水平与其他各器官养分含量采用三参数指数或者五参数双指数拟合最佳。比较三者养分吸收及利用情况可知,钾水平为9 mmol/L(K4)时,氮磷钾生理利用效率较好,较有利于氮磷钾养分吸收利用,实现经济效益最大化。 展开更多
关键词 厚皮甜瓜 吸收与利用
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缓释氧复合材料对上覆水中污染物去除和碱度硬度的影响 预览
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作者 黄荣才 梁艺丰 +4 位作者 丁国良 吴通 刘虹 郑莹莹 刘文莉 《台州学院学报》 2019年第3期42-47,共6页
采用过氧化钙、膨润土、水泥和河砂制备了球形复合缓释氧材料(oxygen slow-releasing bead,简称OSRB),并用于地表黑臭水体中氮磷等污染物的去除。实验室研究结果表明:按每平米底泥表面积投加75 gOSRB后,显著提高了上覆水中CODCr、NH4^+-... 采用过氧化钙、膨润土、水泥和河砂制备了球形复合缓释氧材料(oxygen slow-releasing bead,简称OSRB),并用于地表黑臭水体中氮磷等污染物的去除。实验室研究结果表明:按每平米底泥表面积投加75 gOSRB后,显著提高了上覆水中CODCr、NH4^+-N和总磷(TP)的去除效率,去除率分别为46%、45%和61%(p<0.05)。但NO3^--N和总氮(TN)浓度与对照相比反而有所增加。同时研究发现,投加OSRB后上覆水中的总碱度(TA)和总硬度(TH)略有上升,和不加OSRB处理的对照组没有显著性差别(p>0.05)。研究结论有助于更好地了解OSRB处理对水生生态系统恢复的影响。 展开更多
关键词 缓释氧复合材料 化学需氧量 总碱度 总硬度
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Distribution, residence time, autotrophic production, and heterotrophic removal of DOP in the Mirs Bay, northern South China Sea 预览
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作者 Huaming Shi Yu Ma +2 位作者 Xulu Li Xiaoyong Shi Junxiao Zhang 《海洋学报:英文版》 SCIE CAS CSCD 2019年第8期17-26,共10页
The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeoche... The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeochemistry of DOP is in its infancy. In the present study, monthly data between 2000 and 2014 were used to analyze the temporal and spatial distributions of DOP in the Mir Bay, the northern South China Sea. The DOP residence time(TDOP) was also investigated using a simple regression analysis in combination with chlorophyll a(Chl a) measurements while excess DOP(ΔDOP), produced by the biogeochemical processes of autotrophic production and heterotrophic removal, was determined using a two-component mixing mass-balance model in combination with salinity measurements. The results showed that the DOP concentration was(0.017±0.010) mg/L higher in the surface-water compared with the bottom-water and higher in the inner Tolo Harbour and waters adjacent to Shatoujiao compared with the main zone of the bay. Although seasonal changes and annual variability in the DOP were small, the surface DOP concentration was higher in the wet season(April–September)than in the dry season(October–March) due to the impacts of seaward discharges and atmospheric deposition into the bay. Measurement and regression results showed that the DOP release rate from phytoplankton production was about 1.83(gP)/(gChl a) and the TDOP was about 7 d, which implied that the DOP cycle in the bay was rapid. The ΔDOP was calculated from the model to be about 0.000 mg/L in the main zone of the bay and about 0.002 mg/L in the inner Tolo Harbour and waters adjacent to Shaotoujiao, suggesting that the autotrophic production of DOP was almost balanced by the heterotrophic removal in the main zone of the bay and dominated in the inner Tolo Harbour and waters adjacent to Shaotoujiao. In conclusion, the Mirs Bay is very productive and fairly heterotrophic. 展开更多
关键词 dissolved organic phosphorus temporal and spatial distributions residence time AUTOTROPHIC PRODUCTION HETEROTROPHIC REMOVAL MIRS BAY northern South China Sea
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磷素营养诊断技术的发展及其在马铃薯生产中的应用前景 预览
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作者 孔硕 樊明寿 +3 位作者 秦永林 贾立国 陈杨 于静 《中国马铃薯》 2019年第5期309-313,共5页
利用磷素营养诊断技术,科学地指导作物生产中的磷肥施用,可大幅度提高磷肥利用效率,减少肥料浪费与降低环境风险。从植株外观诊断、土壤分析诊断、无损测试法、植物组织分析诊断、生理生化分析诊断等方面综述了磷素营养诊断技术的原理... 利用磷素营养诊断技术,科学地指导作物生产中的磷肥施用,可大幅度提高磷肥利用效率,减少肥料浪费与降低环境风险。从植株外观诊断、土壤分析诊断、无损测试法、植物组织分析诊断、生理生化分析诊断等方面综述了磷素营养诊断技术的原理、优缺点及其应用,并在分析马铃薯生产中开展磷素营养诊断意义的基础上,提出了磷素营养诊断亟待解决的问题,为马铃薯磷肥高效管理提供参考。 展开更多
关键词 磷素 诊断技术 马铃薯
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给水厂污泥吸附磷前后孔隙结构及表面积变化分析
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作者 仇付国 李林彬 +2 位作者 付昆明 许俊挺 王娟丽 《离子交换与吸附》 CAS 北大核心 2019年第1期60-70,共11页
给水厂污泥含有铝铁化合物而具有良好的吸磷潜力,同时其吸附能力与本身的孔隙结构及比表面积均直接相关。确定污泥吸磷前后孔隙结构变化,对研究给水厂污泥吸磷机理及性能评价具有重要的意义。本文采用低温氮气吸附法,对给水厂污泥吸附... 给水厂污泥含有铝铁化合物而具有良好的吸磷潜力,同时其吸附能力与本身的孔隙结构及比表面积均直接相关。确定污泥吸磷前后孔隙结构变化,对研究给水厂污泥吸磷机理及性能评价具有重要的意义。本文采用低温氮气吸附法,对给水厂污泥吸附磷前后的孔隙结构和比表面积进行了分析,绘制吸附-脱附等温曲线和孔径分布图,计算累积孔内表面积和累积孔体积,定量分析污泥吸磷前后孔隙结构的变化。通过吸附-脱附曲线可判断给水厂污泥主体孔径为介孔,污泥基本孔隙类型为'狭缝型'孔隙。BJH模型得到的孔径分布表明,给水厂污泥中孔径为1.0~16nm的孔隙对表面积贡献最大,对其吸附磷发挥关键作用,污泥吸磷后孔内体积减少14.5%。BET方法分析表明,污泥样品吸附磷前后比表面积分别为62.46m2/g和32.35m2/g,吸磷后比表面积减少了48.2%。同时确立了根据吸附前后污泥孔体积的减少量计算污泥对磷的理论吸附量的方法。 展开更多
关键词 给水厂污泥 吸附脱附曲线 BJH模型 BET模型 孔径分布
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