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Electro-assisted photocatalytic reduction of CO_(2) in ambient air using Ag/TNTAs at the gas-solid interface
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作者 Feng Yue Zhaoya Fan +7 位作者 Cong Li Yang Meng Shuo Zhang Mengke Shi Minghua Wang Mario Berrettoni Jun Li Hongzhong Zhang 《Materials Reports(Energy)》 EI 2024年第2期71-82,共12页
The direct conversion of atmospheric CO_(2) into fuel via photocatalysis exhibits significant practical application value in advancing the carbon cycle.In this study,we established an electro-assisted photocatalytic s... The direct conversion of atmospheric CO_(2) into fuel via photocatalysis exhibits significant practical application value in advancing the carbon cycle.In this study,we established an electro-assisted photocatalytic system with dual compartments and interfaces,and coated Ag nanoparticles on the titanium nanotube arrays(TNTAs)by polydopamine modification.In the absence of sacrificial agent and alkali absorption liquid conditions,the stable,efficient and highly selective conversion of CO_(2) to CO at the gas-solid interface in ambient air was realized by photoelectric synergy.Specifically,with the assistance of potential,the CO formation rates reached 194.9μmol h^(−1) m^(−2) and 103.9μmol h^(−1) m^(−2) under ultraviolet and visible light irradiation,respectively;the corresponding CO_(2) conversion rates in ambient air were 30%and 16%,respectively.The excellent catalytic effect is mainly attributed to the formation of P–N heterojunction during the catalytic process and the surface plasmon resonance effect.Additionally,the introduction of solid agar electrolytes effectively inhibits the hydrogen evolution reaction and improves the electron utilization rate.This system promotes the development of photocatalytic technology for practical applications and provides new insights and support for the carbon cycle. 展开更多
关键词 Electro-assisted photocatalytic Gas-solid interface Ambient air pn heterojunction practical applications
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Fertilization Affects Biomass Production of Suaeda salsa and Soil Organic Carbon Pool in East Coastal Region of China 被引量:5
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作者 MENG Qing-feng YANG Jing-song +2 位作者 YAO Rong-jiang LIU Guang-ming YU Shi-peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第9期1659-1672,共14页
Land use practice significantly affects soil properties. Soil is a major sink for atmospheric carbon, and soil organic carbon (SOC) is considered as an essential indicator of soil quality. The objective of this stud... Land use practice significantly affects soil properties. Soil is a major sink for atmospheric carbon, and soil organic carbon (SOC) is considered as an essential indicator of soil quality. The objective of this study was to assess the effects of N and P applied to Suaeda salsa on biomass production, SOC concentration, labile organic carbon (LOC) concentration, SOC pool and carbon management index (CMI) as well as the effect of the land use practice on soil quality of coastal tidal lands in east coastal region of China. The study provided relevant references for coastal exploitation, tidal land management and related study in other countries and regions. The field experiment was laid out in a randomized complete block design, consisting of four N-fertilization rates (0 (NO), 60 (N1), 120 (N2) and 180 kg ha-1 (N3)), three P-fertilization rates (0 (P0), 70 (P1) and 105 kg ha-~ (P2)) and bare land without vegetation. N and P applied to S. salsa on coastal tidal lands significantly affected biomass production (above-ground biomass and roots), bulk density (Pb), available N and P, SOC, LOC, SOC pool and CMI. Using statistical analysis, significantly interactions in N and P were observed for biomass production and the dominant factor for S. salsa production was N in continuous 2-yr experiments. There were no significant interactions between N and P for SOC concentration, LOC concentration and SOC pool. However, significant interaction was obtained for CMI at the 0-20 cm depth and N played a dominant role in the variation of CMI. There were significant improvements for soil measured attributes and parameters, which suggested that increasing the rates of N and P significantly decreased Pb at the 0-20 cm depth and increased available N and P, SOC, LOC, SOC pool as well as CMI at both the 0-20 and 20-40 cm depth, respectively. By correlation analysis, there were significantly positive correlations between biomass (above- ground biomass and roots) and SOC as well as LOC in 2010 and 2011 across all soil depth, respectively. The treatment with N at 180 kg ha-~ and P at 105 kg ha-1 was superior to the other treatments. The results from the 2-yr continuous experiments indicated that, in short-term, there were a few accumulation of SOC and LOC concentrations by means of N and P application to S. salsa, whereas in the long run, S. salsa with N and P application was recommended for coastal tidal lands because of its great potential of carbon sequestration, improvements of soil nutrition status and promotion of soil quality. 展开更多
关键词 Suaeda salsa production coastal tidal lands n and p application soil organic carbon labile organic carbon carbon management index
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Synthesis of Poly (3-acetylpyrrolyl methine) with Azobenzene Side Groups and Study on Its Third-order Nonlinear Optical Property 被引量:4
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作者 Zhigang ZHANG Hongcai WU +1 位作者 Lingjie MENG Wenhui YI 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第5期715-718,共4页
A novel soluble π-conjugated polymer, poly [(3-acetylpyrrole-2, 5-diyl) p-(N, N-dimethylamino) azobenzylidene] (PAPDMAABE), was synthesized by condensation of 3-acetylpyrrole with 4-aldehyde-4'-dimethylaminoaz... A novel soluble π-conjugated polymer, poly [(3-acetylpyrrole-2, 5-diyl) p-(N, N-dimethylamino) azobenzylidene] (PAPDMAABE), was synthesized by condensation of 3-acetylpyrrole with 4-aldehyde-4'-dimethylaminoazobenzene (ADMAA). The chemical structure of PAPDMAABE was characterized by Fourier transform infrared spectroscopy (FTIR), ^1H-NMR, and UV-Vis-NIR spectra. Transmission electron microscope (TEM) analysis for PAPDMAABE indicates that part of PAPDMAABE is in crystal state, due to the short-range order of the polymer. Thermogravimetric analysis (TGA) curve shows that the polymer has good thermal stability and its decomposition temperature is 248℃. The optical band gap of PAPDMAABE obtained from the optical absorption spectrum is about 1.73 eV. The resonant third-order nonlinear optical property of PAPDMAABE at 532 nm was studied using degenerate four-wave mixing (DFWM) technique. The resonant third-order nonlinear optical susceptibility of the polymer is about 7.48×10^-8 esu. 展开更多
关键词 poly [(3-acetylpyrrole-2 5-diyl) p-(n n-dimethylamino) azobenzylidene] Small optical band gap Degenerate four-wave mixing Third-order nonlinear property
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Synthesis of Poly[(3-octanoylpyrrole-2,5-diyl)-p-(N,N-dimethylamino)benzylidene] and Its Properties by Nitrogen Ion Implantation 被引量:1
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作者 ZHANGZhi-gang WUHong-cai +1 位作者 LIUXiao-zeng YIWen-hui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第2期166-168,共3页
A novel soluble π-conjugated polymer, poly[(3-octanoylpyrrole-2,5-diyl)-p-(N,N-dimethylamino)benzylidene](POPDMABE), was synthesized firstly by the condensation of 3-octanoylpyrrole with para-dimethylaminobenzaldehyd... A novel soluble π-conjugated polymer, poly[(3-octanoylpyrrole-2,5-diyl)-p-(N,N-dimethylamino)benzylidene](POPDMABE), was synthesized firstly by the condensation of 3-octanoylpyrrole with para-dimethylaminobenzaldehyde. The chemical structure of the polymer was characterized by FTIR and 1H NMR spectrometries. The polymer is a potential nonlinear optical(NLO) material. According to the function of optical forbidden band gap(E_g) and photon energy(hν), the optical forbidden band gaps of the polymer before and after ion implantation were calculated. The resonant third-order nonlinear optical properties of POPDMABE before and after ion implantation were also studied by using the degenerate four-wave mixing(DFWM) technique at 532 nm. When the energy is 25 keV and the dose is 2.2×10 17 ions/cm 2, the {polymer′s} optical forbidden band gap is about 1.63 eV which is smaller than that of the non-implanted sample(1.98 eV) and the resonant third-order NLO susceptibility of POPDMABE is about 4.3×10 -7 esu, 1 order of magnitude higher than that of the non-implanted sample(4.1×10 -8 esu). The results show that nitrogen ion implantation is an effective method to improve the resonant third-order NLO property of the polymer. 展开更多
关键词 poly[(3-octanoylpyrrole-2 5-diyl)-p-(n n-dimethylamino)benzylidene] Ion implantation Optical forbidden band gap Resonant third-order nonlinear optical property Degenerate four-wave mixing technique
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Relationship between Leaf Micro- and Macro-Nutrients in Top Canopy Trees in a Mixed Forest in the Upper Rio Negro in the Amazon Region
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作者 M. A. Sobrado 《American Journal of Plant Sciences》 2014年第10期1423-1431,共9页
The mixed forests of the upper Rio Negro at the northern of the Amazon basin grow in oxisol soils that are extremely infertile. These areas exhibit deficiencies in several macro-nutrients, and may also be characterize... The mixed forests of the upper Rio Negro at the northern of the Amazon basin grow in oxisol soils that are extremely infertile. These areas exhibit deficiencies in several macro-nutrients, and may also be characterized by the shortage or toxic excess of some micronutrients. The overall goal of this research is to collect more comprehensive information regarding the micronutrient composition of the upper Rio Negro forests as well as discern the relationship between leaf micro- and macro-nutrients that may contribute to the homeostasis and balance of the ionome. Firstly, the nutrient composition within the oxisol soil and leaf tissues of two top canopy tree species from the mixed forests was determined. We then analyzed the relationship between leaf micronutrient composition with N and P levels of the two species and that of species inhabiting the Amazon caatinga. Extractable soil Zn, B, Mn and Cu were very low in the mixed forest. In contrast, Fe and Al levels were potentially toxic. The analysis of leaf N/P ratios revealed for the first time the co-limitation of N and P in the mixed forest. This contrasts with species from the adjacent Amazon caatinga toposequence that are characterized by strong N limitation. All micronutrients within leaves of species inhabiting the mixed forest were also found to have low concentrations. Moreover, Fe and Al were detected at concentrations well below those reported for accumulator species. This suggested that leaf ion homeostasis was maintained under potentially toxic soil Fe and Al conditions. Leaf micronutrient (Fe, Zn and B) contents mirrored that of leaf N and P contents, and comparable Fe/N, Fe/P, Zn/N, Zn/P, B/N as well as B/P ratios were found across species and forest types. Therefore, forest species exhibited the capability to maintain leaf nutrient balances under soil conditions with deficient or toxic levels of micronutrients. 展开更多
关键词 AMAZOn Forests AMAZOn Caatinga LEAF Ionome Homeostasis LEAF n-p and MICROnUTRIEnTS Micro-nutrient Deficiency MICROnUTRIEnTS Toxicity mixed Forest n-p Co-Limitation plant nUTRIEnT Balance Oxisol pODZOL
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Ground Application System Design for Future Q/V-band Very High-Throughput Satellite
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作者 LI Xinhua LI Jinlin +1 位作者 WANG Xinrong ZHANG Lei 《Aerospace China》 2019年第2期12-23,共12页
Over the next decade,Very High-Throughput Satellite (VHTS) will bring enough capacity to serve high speed internet and in-flight connectivity markets at scale,offering fiber-like services both in terms of price and sp... Over the next decade,Very High-Throughput Satellite (VHTS) will bring enough capacity to serve high speed internet and in-flight connectivity markets at scale,offering fiber-like services both in terms of price and speed.In this context,a generic VHTS mission utilizing Q/V-band feeder links and Ka-band user links is described.However,the rain attenuation on the feeder links becomes a limiting issue because of the higher frequencies.Toward this,an exploitation of multiple gateways (GWs) as a transmit diversity measure for overcoming severe propagation effects are being considered.Ground Application System (GAS) design of VHTS is illustrated including N+P GWs (N active and P redundant GWs) diversity,frequency plan,link budget and system capacity. 展开更多
关键词 ground application system Q/V-band VHTS GATEWAY DIVERSITY n%pLUS%p scheme
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固氮树种在混交林中的作用研究Ⅱ.固氮树木叶部N、P养分动态特征 被引量:9
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作者 何兴元 张成刚 +4 位作者 杨思河 陈玮 张粤 刘惠昌 苏道岩 《应用生态学报》 CAS CSCD 1997年第3期235-239,共5页
研究了 2 3种固氮与非固氮树种叶部N、P含量的季节变化、输出率以及叶片衰老过程中N、P的输出过程 .结果表明 ,供试树种叶部N、P含量均存在着明显的季节变化 ,平均变化率为 2 1~ 2 3% ,最大变化率出现在叶片衰老期 .在衰老期内不同树... 研究了 2 3种固氮与非固氮树种叶部N、P含量的季节变化、输出率以及叶片衰老过程中N、P的输出过程 .结果表明 ,供试树种叶部N、P含量均存在着明显的季节变化 ,平均变化率为 2 1~ 2 3% ,最大变化率出现在叶片衰老期 .在衰老期内不同树种表现出不同的N、P动态特征 .固氮树种表现出低输出率 ,落叶中N含量是非固氮树种的 1 .6~ 3.7倍 .固氮树种生长季叶部N含量在 2 .5%左右 . 展开更多
关键词 森林生态学 固氮树种 养分动态 混交林
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新试剂N-间甲苯基-N′-(氨基对苯磺酸钠)硫脲(MMPT)的合成及其在分析化学中的应用 被引量:10
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作者 马东兰 马狂飚 +1 位作者 李建平 王玉炉 《分析试验室》 CAS CSCD 1997年第4期17-20,共4页
本文合成新试剂N-间甲苯基-N′-(氨基对苯磺酸钠)硫脲(MMPT),经红外、紫外、核磁、元素分析等测试,确定其结构。研究测定了试剂与40多种离子的反应及其配合物的表观摩尔吸光系数,它可作为Cu2+(m=0.015μ... 本文合成新试剂N-间甲苯基-N′-(氨基对苯磺酸钠)硫脲(MMPT),经红外、紫外、核磁、元素分析等测试,确定其结构。研究测定了试剂与40多种离子的反应及其配合物的表观摩尔吸光系数,它可作为Cu2+(m=0.015μg,c=0.5μg/mL)、Ag+(m=0.1μg,c=3.3μg/mL)的新鉴定试剂和光度法测定Pd2+(ε309.7=6.32×104L·mol-1·cm-1)、Pt(Ⅳ)(ε754.4=8.58×104L·mol-1·cm-1)等的显色剂,方法灵敏度高、选择性好,用于阳极泥、人发、矿石及催化剂中上述元素的鉴定或测定,均获满意结果。 展开更多
关键词 硫脲衍生物 显色剂 MMpT
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N,P,K对不同土壤肥力土壤辣椒产量的影响 被引量:5
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作者 张昕 葛晓光 +2 位作者 王晓雪 候利军 杨日东 《沈阳农业大学学报》 CAS CSCD 1996年第2期144-147,共4页
以不同肥力水平的壤质草旬土为基质,进行N,P、K完全设计盆栽试验。结果表明:不同肥力土壤配施N,P,K,辣椒增产效果不同.土壤肥力高的土壤,辣椒对土壤肥力的依存率为76.93%,中肥力土壤为67.33%,低肥力土壤为... 以不同肥力水平的壤质草旬土为基质,进行N,P、K完全设计盆栽试验。结果表明:不同肥力土壤配施N,P,K,辣椒增产效果不同.土壤肥力高的土壤,辣椒对土壤肥力的依存率为76.93%,中肥力土壤为67.33%,低肥力土壤为62.25%,而肥效则以低肥力土壤为最高。 展开更多
关键词 辣椒 肥效 盆栽试验 氮肥 磷肥 钾肥
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NMP-DMAC溶剂体系中制备PPTA的研究 被引量:3
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作者 张跃 谢瑞刚 +2 位作者 严生虎 刘建武 沈介发 《化工新型材料》 CAS CSCD 北大核心 2010年第12期71-74,共4页
以对苯二胺和对苯二甲酰氯为单体,三正丁胺为酸性气体吸收剂,在N-甲基吡咯烷酮和N,N-二甲基乙酰胺的氯化钙的混合溶液体系中,采用低温溶液缩聚法制备了聚对苯二甲酰对苯二胺聚合物。研究了TPC过量值、单体PPD摩尔浓度、溶剂配比、CaCl2... 以对苯二胺和对苯二甲酰氯为单体,三正丁胺为酸性气体吸收剂,在N-甲基吡咯烷酮和N,N-二甲基乙酰胺的氯化钙的混合溶液体系中,采用低温溶液缩聚法制备了聚对苯二甲酰对苯二胺聚合物。研究了TPC过量值、单体PPD摩尔浓度、溶剂配比、CaCl2用量、TBA用量等因素对聚合物性能的影响。结果表明:当TPC过量值为8‰~9‰、PPD摩尔浓度为0.4 mol/L、溶剂配比为3∶1、CaCl2用量为6%、TBA投加量为PPD摩尔数的2倍时,可以获得性能较佳的PPTA聚合物。与现有的专利技术相比,该合成工艺的混合溶剂体系及酸吸收剂具有新颖性。 展开更多
关键词 ppTA 低温溶液缩聚 混合溶剂体系 三正丁胺
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p-n异质结光催化剂的制备及性能的研究进展 被引量:6
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作者 郑先君 黄娟 +2 位作者 魏丽芳 魏明宝 魏永杰 《河南化工》 CAS 2011年第5期21-23,共3页
p-n异质结光催化剂材料因其具有特殊的能带结构和载流子输送特性,在光催化领域得到重视。本文重点介绍各种类型的p-n异质结光催化剂的研究现状,并对未来的研究方向进行了展望。
关键词 p-n异质结 光催化剂 应用
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高效液相色谱法测定NEPE推进剂中的安定剂 被引量:4
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作者 吴婉娥 付潇 +3 位作者 任雷涛 裴海潮 王广 强洪夫 《化学推进剂与高分子材料》 CAS 2015年第6期87-90,共4页
建立了一种安定剂含量的高效液相色谱测定方法,该方法可同时测定NEPE(硝酸酯增塑聚醚)推进剂中的MNA(N–甲基对硝基苯胺)和2–NDPA(2–硝基二苯胺),通过实验获得了最佳色谱测定条件;绘制了2种安定剂的标准曲线,相关系数均大于0.9... 建立了一种安定剂含量的高效液相色谱测定方法,该方法可同时测定NEPE(硝酸酯增塑聚醚)推进剂中的MNA(N–甲基对硝基苯胺)和2–NDPA(2–硝基二苯胺),通过实验获得了最佳色谱测定条件;绘制了2种安定剂的标准曲线,相关系数均大于0.99。在最佳色谱条件下对推进剂样品的测试结果显示,该方法的相对标准偏差≤0.76%,相对误差≤7%,加标回收率为89%~111%,证明所建立的方法准确可靠。 展开更多
关键词 液相色谱 混合安定剂 2–硝基二苯胺 n–甲基对硝基苯胺
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扬花期叶面施锌对寒地水稻Zn、N、P、K吸收和积累的影响 被引量:3
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作者 刘春梅 张明聪 +2 位作者 王孟雪 张兴梅 何淑平 《安徽农学通报》 2020年第13期87-91,共5页
为探讨水稻施用外源锌对氮、磷、钾吸收和积累的规律,采用盆栽模拟试验方法,研究了不同锌浓度对水稻植株和子粒氮、磷、钾吸收、积累的影响。结果表明,水稻各器官锌含量的顺序为:植株>颖壳>精米,随着外源锌浓度的增加,锌含量显著... 为探讨水稻施用外源锌对氮、磷、钾吸收和积累的规律,采用盆栽模拟试验方法,研究了不同锌浓度对水稻植株和子粒氮、磷、钾吸收、积累的影响。结果表明,水稻各器官锌含量的顺序为:植株>颖壳>精米,随着外源锌浓度的增加,锌含量显著增加,Zn2(5g/kg)处理精米锌含量为39.40mg/kg,是对照的1.9倍,能保证人们每日膳食锌的摄入。随着锌浓度的增加,植株和颖壳锌分配比例增加,而籽粒分配比例则下降。植株中锌向精米运转率增加,Zn2处理比对照增加12.73个百分点。随着外源锌浓度增加,水稻植株、颖壳和精米的氮、钾含量均增加,而磷含量下降,Zn2处理(5g/kg)精米氮含量和钾含量增加10.01%、1.16%,磷含量下降了12.26%。植株Zn含量与植株、精米和颖壳中氮含量、钾含量极显著正相关,与精米和颖壳中磷含量极显著负相关。随着锌浓度的增加,各器官氮、钾积累量均增加,磷积累量下降。因此,对于寒地水稻品种垦粳7号,扬花期喷施5g/kg锌,能显著提高精米锌含量,并且有利于水稻对氮、钾的吸收和利用。 展开更多
关键词 叶面喷锌 寒地水稻 Znnp、K吸收和积累
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P·Zn组合对小麦生长·产量和籽粒含氮量的影响
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作者 尹恩 武际 郭熙盛 《安徽农业科学》 CAS 北大核心 2009年第15期6920-6922,共3页
[目的]探讨P、Zn组合对小麦生长的影响机理。[方法]采用盆栽试验,研究砂姜黑土中P、Zn配施对小麦生长期产量以及籽粒氮素含量的影响。[结果]结果表明,小麦苗期和抽穗期P、Zn呈协同关系,成熟期明显出现P、Zn拮抗。适当的P、Zn配比有利于... [目的]探讨P、Zn组合对小麦生长的影响机理。[方法]采用盆栽试验,研究砂姜黑土中P、Zn配施对小麦生长期产量以及籽粒氮素含量的影响。[结果]结果表明,小麦苗期和抽穗期P、Zn呈协同关系,成熟期明显出现P、Zn拮抗。适当的P、Zn配比有利于小麦籽粒产量的提高和经济效益的增加。P0.3Zn0.2处理的产量最高,与其他处理间在0.05水平有差异,P0.3Zn0.4、P0.9Zn0.2、P0.9Zn0.4间的产量在0.05水平无差异,Zn0处理的产量最低。[结论]低P背景下,施Zn肥能促进小麦根系的生长;高P背景下,施适量Zn肥能促进小麦根系生长,但高Zn时出现P、Zn拮抗。 展开更多
关键词 小麦 p、Zn配施 产量 氮素吸收
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NP配施对平茬后云南松苗木N、P、K化学计量比的影响 被引量:2
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作者 陆庄跃 杨振欣 +3 位作者 郑超凡 罗茜 蔡年辉 许玉兰 《植物研究》 CAS CSCD 北大核心 2023年第2期218-230,共13页
为了解NP配施对平茬后云南松(Pinus yunnanensis)苗木各器官N、P、K化学计量比的影响,分析云南松苗木不同器官(根、茎、叶、萌条)的ω(N)∶ω(P)、ω(N)∶ω(K)、ω(P)∶ω(K)化学计量比的季节变化特征,探讨各器官间N、P、K化学计量比... 为了解NP配施对平茬后云南松(Pinus yunnanensis)苗木各器官N、P、K化学计量比的影响,分析云南松苗木不同器官(根、茎、叶、萌条)的ω(N)∶ω(P)、ω(N)∶ω(K)、ω(P)∶ω(K)化学计量比的季节变化特征,探讨各器官间N、P、K化学计量比的相关性及其变异来源。采用N、P二因素三水平的3×3回归设计开展不同施肥试验,并对苗木采样测定,研究NP配施对平茬后云南松根、叶、茎及其萌条N、P、K化学计量特征的影响。结果表明:平茬后云南松苗木不同器官的营养元素分配没有统一的规律,展现出丰富的变异。随着施肥季节的变化,ω(N)∶ω(P)在根、茎和萌条中逐渐下降,在叶中先下降后上升,但总体差异不大。单施N肥、P肥和NP配施均对云南松苗木生长的影响产生一定差异,总体来看NP配施更有利于促进苗木的生长,且以处理5(N_(1)P_(1))表现为极显著(P<0.01)。云南松苗木各器官N、P、K化学计量比主要受N×P交互作用的影响,其次是N,影响最小的是P。除在根和叶中ω(N)∶ω(P)与ω(N)∶ω(K)之间相关性发生改变之外,其余两两间的正负相关性均保持不变,而ω(N)∶ω(P)与ω(P)∶ω(K)、ω(N)∶ω(K)与ω(P)∶ω(K)的相关性均随着施肥季节的变化相关性发生改变,且相关系数降低,分别受P和K的调控。平茬改变植株体内的营养元素含量,不同施肥处理促使云南松各器官中N、P、K化学计量特征差异极显著(P<0.01)。NP配施可以有效缓解单施N肥、P肥对植株的限制作用,使养分处于一个平衡状态,从而满足植株对生长的需要。 展开更多
关键词 云南松 np配施 施肥季节 化学计量比
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NPK用量对露地西兰花产量、养分累积及肥料效率的影响 被引量:6
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作者 白建忠 陈泽 +3 位作者 丁永锋 张珞 黄萍 赵营 《中国农学通报》 2018年第31期112-118,共7页
为了探讨露地西兰花的NPK合理施用量,提出科学的施肥配比。在宁夏引黄灌区通过田间试验研究了不同NPK供应水平对露地西兰花产量和地上部NPK吸收累积的影响,并评价了其肥料效率。结果表明:施用N、P肥对西兰花有显著增产作用,而施K处理间... 为了探讨露地西兰花的NPK合理施用量,提出科学的施肥配比。在宁夏引黄灌区通过田间试验研究了不同NPK供应水平对露地西兰花产量和地上部NPK吸收累积的影响,并评价了其肥料效率。结果表明:施用N、P肥对西兰花有显著增产作用,而施K处理间无显著差异。相对于N0和P0处理,增施N、P肥可分别提高23.6%~36.2%和7.6%~11.5%的经济产量。适当增施NPK肥能显著提高西兰花的地上部NPK养分累积。西兰花的肥料利用率、农学效率和偏生产力都随施肥量增加而降低。每施用1 kg N、1 kg P_2O_5、1 kg K2O分别可生产50.9~184.7、89.3~369.1、53.9~220.2 kg西兰花经济产量,其随施肥量增加呈显著降低趋势。西兰花经济产量与施N量(R2=0.886)、施P量(R2=0.906)和施K量(R2=0.794)都呈二次曲线关系。综合考虑蔬菜产量、养分累积和肥料效率,建议宁夏引黄灌区露地西兰花的施肥量分别为N 189.8~200.0 kg/hm^2、P_2O_579.8~86.8 kg/hm^2和K2O 80.2~112.5 kg/hm^2,其施肥配比为1:0.42~0.43:0.42~0.56。 展开更多
关键词 npK用量 露地西兰花 产量 地上部n p K 肥料利用率 肥料农学效率 肥料偏生产力
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NPK配施对皖草2号产量及品质的影响 被引量:1
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作者 杨勇 杨安中 《安徽农业科学》 CAS 2004年第4期707-707,709,共2页
研究了NPK配合施用对皖草 2号产量及品质的影响。结果表明 :NPK肥配合施用可提高皖草 2号产量 ,改善品质 ,其中NPK配合施用较只施N肥增产 11.7% ,比不施肥增产 5 5 .9% ;NPK肥配合施用较不施肥处理粗蛋白、粗脂肪含量分别增加 9.5 8、1... 研究了NPK配合施用对皖草 2号产量及品质的影响。结果表明 :NPK肥配合施用可提高皖草 2号产量 ,改善品质 ,其中NPK配合施用较只施N肥增产 11.7% ,比不施肥增产 5 5 .9% ;NPK肥配合施用较不施肥处理粗蛋白、粗脂肪含量分别增加 9.5 8、1.45个百分点 ,而粗纤维含量降低 5 .5 9个百分点。 展开更多
关键词 nKp 皖草2号 产量 品质
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基于A/O工艺含油掺混污水C/S/N/P去除效能研究
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作者 胡蓓 魏利 +1 位作者 李春颖 魏东 《哈尔滨商业大学学报(自然科学版)》 CAS 2018年第5期541-544,共4页
油田含油污水的达标外排以及深度处理是油田含油污水处理的难点.研究将油田含油污水与生活污水掺混,生活污水为整个反应系统提供磷元素,采用A/O工艺,通过分别投加SO_4^(2-)、NO_3^-作为电子受体,分析C/S/N/P同步去除情况.结果表明,SO_4^... 油田含油污水的达标外排以及深度处理是油田含油污水处理的难点.研究将油田含油污水与生活污水掺混,生活污水为整个反应系统提供磷元素,采用A/O工艺,通过分别投加SO_4^(2-)、NO_3^-作为电子受体,分析C/S/N/P同步去除情况.结果表明,SO_4^(2-)去除率为95%,NO_3^--N去除率为96%,PO_4^(3-)去除率为35. 71%,COD≤100 mg/L,含油量≤1 mg/L,该研究为含油污水生物处理外排工业化推广提供理论和技术的支持. 展开更多
关键词 含油掺混废水 A/O工艺 电子受体 C/S/n/p同步去除 效能
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高溶解度活性黑P-MN印制性能研究
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作者 王小红 陈晶晶 徐华良 《染整技术》 CAS 北大核心 2016年第12期39-41,51,共4页
介绍了一种新结构黑色活性印花染料P-MN的应用性能。与科华素黑P-N相对照,新活性黑P-MN的溶解度达到250 g/L,比科华素黑P-N有大幅提升。在其他应用性能上,活性新黑P-MN与科华素黑P-N相当或略有改善。新型活性印花黑P-MN的应用更为稳定可... 介绍了一种新结构黑色活性印花染料P-MN的应用性能。与科华素黑P-N相对照,新活性黑P-MN的溶解度达到250 g/L,比科华素黑P-N有大幅提升。在其他应用性能上,活性新黑P-MN与科华素黑P-N相当或略有改善。新型活性印花黑P-MN的应用更为稳定可靠,是科华素黑P-N的理想升级替代品。 展开更多
关键词 活性黑p-Mn 科华素黑p-n 溶解度 应用性能
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N-对甲苯基N’-(氨基对苯磺酸钠)硫脲的合成及其分析应用 被引量:11
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作者 黄运瑞 马东兰 +2 位作者 张雷 孙瑞霞 李建平 《冶金分析》 CAS CSCD 北大核心 2001年第1期7-9,共3页
合成了新试剂N 对甲苯基 N’ (氨基对苯磺酸钠 )硫脲 (PMPT) ,经红外、紫外、核磁和元素分析等测试 ,确定了其组成和结构。并研究测定了试剂与 40多种常见离子的反应及其络合物的表观摩尔吸光系数 ,表明它可作为Cu2 + (m =0 0 15 μg ... 合成了新试剂N 对甲苯基 N’ (氨基对苯磺酸钠 )硫脲 (PMPT) ,经红外、紫外、核磁和元素分析等测试 ,确定了其组成和结构。并研究测定了试剂与 40多种常见离子的反应及其络合物的表观摩尔吸光系数 ,表明它可作为Cu2 + (m =0 0 15 μg ,c =0 5 0 μg/mL) ,Ag+ (m =0 10 μg ,c =3 3μg/mL)的新鉴定试剂和光度法测定Cu2 + (ε36 5 5 =8 36× 10 4)的新显色剂。 展开更多
关键词 硫脲 合成 pMpT 分析 显色剂 光度法
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