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Characteristics and distribution of phosphorus in surface sediments of a shallow lake

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Journal of Environmental Sciences 2023年第2期124卷 50-60页

作者： Ziwei Long Zehua Ji Yuansheng pei State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China The Key Laboratory of Water and Sediment Sciences Ministry of EducationSchool of EnvironmentBeijing Normal UniversityBeijing 100875China

phosphorus(p)in sediments plays an important role in shallow lake ecosystems and has a major effect on the lake environment.The mobility and bioavailability of p primarily depend on the contents of different p forms,which in turn depend on the sedimentary environment.Here,sediment samples from Baiyangdian(BYD)lake were collected and measured by the Standards,Measurements,and Testing procedure and phosphorus-31 nuclear magnetic resonance spectroscopy(31p nmr)to characterize different p forms and their relationships with sediment physicochemical properties.The p content in the sediments varied in different areas and had characteristics indicative of exogenous river input.Inorganic p(334–916 mg/kg)was the dominant form of p.The 31p nmr results demonstrated that orthophosphate monoesters(16–110 mg/kg),which may be a source of p when redox conditions change,was the dominant form of organic p(20–305 mg/kg).The distribution of p forms in each region varied greatly because of the effects of anthropogenic activities,and the regions affected by exogenous river input had a higher content of p and a higher risk of p release.principal component analysis indicated that p bound to Fe,Al,and Mn oxides and hydroxides(NaOH-p)and organic p were mainly derived from industrial and agricultural pollution,respectively.Redundancy analysis indicated that increases in pH lead to the release of NaOH-p.Organic matter plays an important role in the organic p biogeochemical cycle,as it acts as a sink and source of organic p.

关键词： Sediment phosphorus forms SMT 31p nmr

Crystal Structure of a Novel palladium (Ⅰ)-Rhodium (Ⅱ) Heterodinuclear Complex and Its 31p nmr Study

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progress in Natural Science:Materials International 1993年第2期 165-168页

作者：吕士杰韦凤萍汪汉卿黄梁仁 Academia Sinica Fujian Institute of Research on the Structure of Matter.Academia Sinica.Fuzhou 350002 Fuzhou Laboratory of Structure Chemistry Fuzhou 350002 Lanzhou 730000 pRC State Key Labonatory of Oxo Synthesis and Selective Oxidation.Lanzhou Institute of Chemical physics

1 IntroductionHeterodinuclear complexes are very attractive because of their novel structural andreactive features and their potential application to catalysis.In these complexes,two dif-ferent metal atoms or ions in the same molecule may cooperate to facilitate some reaction,which could not be handled by a single metal center,leading to new types of reactionsand affording new opportunites.Four pd-Ag heterodinuclear complexes bridged withdppm were prepared and characterized.Their31p-{~1H}nmr spectra were analyzed.The molecular structure of trans(NC)2pd(dppm)2Ag(NO2)was reported.Now our interestis extended to a series of pd-Rh complexes.In this note the molecular structure of aheterodinuclear complex,trans(NC)2[p(CH3O)3] Rh(μ-dppm)2pdC1(1),and its formation pro-cesses,such as ligands migration,intermetallic redox and metal-metal bonding arepresented.

关键词： ■ p■ 31p nmr

31p nmr应用于磷酰化氨基酸手性选择的研究

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31P NMR应用于磷酰化氨基酸手性选择的研究

作者：张兴华厦门大学

学位级别：硕士

磷是生命的中心元素,所有的生命活动过程都直接或间接有磷的参与。磷做为遗传物质DNA基本骨架存在于磷酸二酯键中;磷酸双酯(DNA和RNA)、三磷腺酐(ATp)调控着整个生命过程,它们参与物质的代谢、能量的转化、遗传的表达等几乎所有的生化过... 详细信息

磷是生命的中心元素,所有的生命活动过程都直接或间接有磷的参与。磷做为遗传物质DNA基本骨架存在于磷酸二酯键中;磷酸双酯(DNA和RNA)、三磷腺酐(ATp)调控着整个生命过程,它们参与物质的代谢、能量的转化、遗传的表达等几乎所有的生化过程;绝大多数酶的催化反应是以它们的磷酰化和去磷酰化来调控的。磷在生命活动中起着极为重要的作用,被誉为“生命活动的调控中心”。氨基酸是组成蛋白质的基本单位,蛋白激酶上氨基酸侧链的磷酸化调控着蛋白的结构及功能。因此,N-磷酰化氨基酸可作为研究磷酰基参与下的生物有机化学反应基本规律的模型。首先,本论文从氨基酸角度研究磷化学,合成了一系列模型化合物N-磷酰化氨基酸,利用p nmr技术研究了磷上酯交换反应,发现α-氨基酸对于磷原子存在着手性选择现象,并且这种手性选择的差异随α-氨基酸种类的不同也有所区别。论文中利用HpLC、ESI-MS、ESI-MS/MS以及HpLC-ESI-MS等技术系统的研究了各种条件对氨基酸手性选择的影响,发现了N-磷酰化α-氨基酸的磷上酯交换反应是一个分子内自催化的过程,氨基酸侧链基团的立体化学效应以及杂原子的催化作用是造成氨基酸手性选择的主要因素。其次,从磷化学的角度研究了氨基酸的立体化学对酯交换反应的结构效应,发现了以磷酰基保护的氨基酸以及含磷缩合试剂的方法进行多肽的合成,氨基酸消旋现象很少发生。p nmr跟踪成肽反应,发现了L-构型氨基酸对于L-构型与D-构型氨基酸的化学反应活性存在着一定的差异。

关键词： 31p nmr N-磷酰化氨基酸手性选择

果蔬中多农残19F和31p nmr定量检测方法的研究

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果蔬中多农残19F和31P NMR定量检测方法的研究

作者：严伟北京化工大学

学位级别：硕士

食品安全一直是社会大众关注的热点话题，而食品中农产品的农药残留问题也一直是人们关注的焦点。食品中的农药残留量超标，会影响消费者的人身安全，因此，迫切需要发展快速、准确的检测方法，定量检测食品中的农药残留。传统除草剂... 详细信息

食品安全一直是社会大众关注的热点话题，而食品中农产品的农药残留问题也一直是人们关注的焦点。食品中的农药残留量超标，会影响消费者的人身安全，因此，迫切需要发展快速、准确的检测方法，定量检测食品中的农药残留。传统除草剂、杀虫剂、杀菌剂中，含氟农药种类很多。科技的发展，带动了农药种类的创新。新型农药，尤其是有机氟农药由于其高效、低毒、低残留的特点，使用迅速扩展。有机磷农药在是传统农药中本来就占有很大一部分比例。这些农药残留在水果蔬菜等食品中，对食品安全造成了很大威胁。核磁共振检测本身具有样品制备快速简单、不需将待测组分和其他组分完全分离，不破坏样品、无需高纯度参照、静态检测稳定性高等优点。结合这些优点，我们开发了用F和p nmr分别定量检测水果蔬菜中的多种含氟农药和有机磷类农药的方法，可以在25分钟内同时对三种有机氟或者有机磷农药进行定量分析。我们对方法在线性、组内和组间精密性、回收率等方面进行了考察。本文通过对F和p nmr采样参数和数据处理参数的优化，以及样品前处理的改进，在25分钟内，对黄瓜中的三种有机氟农药残留同时进行了定量分析。三种有机氟农药氟酰胺、高效氯氟氰菊酯、氟硅唑的方法检出限依次为0.42mg/Kg、0.56mg/Kg、1.82mg/Kg，定量限依次为1.40mg/Kg、1.86mg/Kg、6.07mg/Kg，三种有机磷农药乙酰甲胺磷、二嗪磷、丙溴磷的方法检出限依次为13.19mg/Kg、12.82mg/Kg、33.04mg/Kg，定量限依次为43.97mg/Kg、42.75mg/Kg、110.13mg/Kg。所有农药在不同浓度水平的组内相对标准偏差小于10%，组间相对标准偏差小于15%，仪器和方法的精密性良好。六种农药在高、中、低三个浓度水平上的加标回收率都在70%到100%之间，表明所建立的方法可以同时准确快速测定果蔬中的多种有机氟或者有机磷农药。

关键词：农残 19Fnmr 31p nmr 定量快速检测

phosphorus speciation in the sediment profile of Lake Erhai, southwestern China: Fractionation and ^(31)p nmr

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Journal of Environmental Sciences 2013年第6期25卷 1124-1130页

作者： Runyu Zhang Liying Wang Fengchang Wu Baoan Song State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of Sciences State Environmental protection Key Laboratory for Lake pollution Control Chinese Research Academy of Environmental Sciences Key Laboratory of Green pesticide and Agricultural Bioengineering Ministry of Education

The distribution characteristics of phosphorus （p） forms in the sediment profile of Lake Erhai, in southwestern China has been investigated by sequential extraction and 31p nuclear magnetic resonance spectroscopy （nmr） of NaOH extracts to understand p dynamics and its potential contribution to lake eutrophication. Contents of p fractions varied in the order of NH4C1 extracted p （NH4C1- p）〈 bicarbonate-dithionite extracted p （BD-p）〈 HC1-p, Residual-p 〈 NaOH extracted p （NaOH-p）. The highly available NH4C1-p represented less than 1% of total p （Tp）. BD-p and NaOH extracted reactive p （NaOH-rp） averaged 39%, while the ratio of Fe/p was higher than 15, indicating low p release from the sediments under permanent oxic condition. The less bio-available HC1-p, NaOH extracted nonreactive p （NaOH-nrp） and residual-p contributed 61% of Tp. Regression analysis revealed that BD-p, NaOH-rp and HC1-p were positively correlated with the contents of Fe and Mn, A1 and Fe, and Ca, respectively. The investigation of p compound groups in NaOH extracts by 31p nmr showed that ortho-p and monoester-p were the largest two constituents of the p pool, followed by diester-p, phosphonate and pyro-p. A comparison of vertical variations of p groups in the sediment profile suggested that these compounds were involved in the p recycling to different extents in Lake Erhai. In particular, the lake exhibits high potential for labile p release from the surface sediments, which should be taken into consideration even after the outsourced p runoff ceased.

关键词： phosphorus speciation fractionation 31p nmr sediment eutrophication

^(31)p nmr Study on Some phosphorus-Containing Compounds

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Chinese Chemical Letters 2000年第12期11卷 1057-1060页

作者： Zhen XU Ji Liang SHI Xin CHEN Xi Kui JIANG Shanghai Institute of Organic Chemistry Chinese Academy of Sciences354 Fenglin RoadShanghai 200032

31p nmr has become a widely applied spectroscopic probe of the structure of phosphorus-containing compounds. Meanwhile, the application of 31p nmr has been rapidly expanded to biochemistry and medicinal chemistry of phosphorus-containing compounds because the growing importance of the phosphorus compounds is now widely realized. We report here the results of 31p nmr study on some phosphorus-containing compounds, namely, O-alkyl O-4-nitrophenyl methyl phosphonates with different alkyl chain-length (MepO-n), 4-nitrophenyl alkylphenylphosphinates with different alkyl chain-length (php-n), diethyl phosphono- acetonitrile anion and diethyl phosphite anion . Our results indicate that 31p nmr can not only be applied to not only the study of the hydrolytic reactions of MepO-8 and php-8 but also be applied to the study of the presence of the anions of diethylphosphonoacetonitrile and diethyl phosphite in nucleophilic reactions.

关键词： 31p nmr phosphorus-containing compounds nucleophilic reaction.

Quantum Chemistry Studies on the Fe-Cu Interactions and ^(31)p nmr in Fe(CO)_3(ph_2ppy)_2(CuX_n) (X_n=Cl_2^(2-),Cl^-,Br^-)

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Chinese Journal of Structural Chemistry 2008年第11期27卷 1339-1348页

作者：许旋李勤瑜方亮孙世玲苏忠民 School of Chemistry and Environment South China Normal University Institute of Functional Material Chemistry Faculty of ChemistryNortheast Normal University

In order to study the Fe-Cu interactions and their effects on 31p nmr, the structures of mononuclear complex Fe（CO）3fphzppy）a 1 and binuclear complexes Fe（CO）3（phEppy）z（CuXn）（2： Xn = Cl2^2-, 3： Xn = Cl-, 4： Xn = Br-） are calculated by density functional theory （DFT） pBE0 method. For complexes 1, 3 and 4, the 31p nmr chemical shifts calculated by pBE0-GIAO method are in good agreement with experimental results. The 31p chemical shift is 82.10 ppm in the designed complex 2. The Fe-Cu interactions （including Fe→Cu and Fe←Cu charge transfer） mainly exhibit the indirect interactions. Moreover, the Fe-Cu（I） interactions （mostly acting as σFe-p→4Scu and aFe-C→4Scu charge transfer） in complexes 3 and 4 are stronger than Fe-Cu（Ⅱ） interactions （mostly acting as σFe-p→4Scu and σFe-p←4Sc,） in complex 2. In complex 2, the stronger Fe←Cu interac- tions, acting as σFe-p←44SCu charge transfer, increase the electron density on p nucleus, which causes the upfield 31p chemical shift compared with mononuclear complex 1. For 3 and 4, although a little deshielding for p nucleus is derived from the delocalization of σFe-p→4Scu due to the Fe→Cu interactions, the stronger σFe-c→np charge-transfer finally increases the electron density on p nucleus. As a result, an upfield 31p chemical shift is observed compared with 1. The stability follows the order of 2〉3=4, indicating that Fe（CO）3（phzppy）2（CuCl2） is stable and could be synthesized experimentally. The N-Cu（Ⅱ） interaction plays an important role in the stability of 2. Because the delocalization of σFe-p→4SCu and σFe-c→πc-o weakens the a bonds of Fe-C and ~r bonds of CO, it is favorable for increasing the catalytic activity of binuclear complexes. Complexes 3 and 4 are expected to show higher catalytic activity compared to 2.

关键词： DFT （pBE0） GIAO 31p nmr metal-metal interaction

^(31)p nmr Studies on the Ligand Dissociation of Trinuclear Molybdenum Cluster Compounds

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Chinese Journal of Chemistry 2003年第9期21卷 1174-1177页

作者：李兆基覃业燕唐艳红康遥夏继波陈忠吴棱姚元根 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China Department of Chemistry Xiamen University Xiamen Fujian 361005 China

A series of carboxylate-substituted trinuclear molybdenum cluster compounds formulated as Mo 3S 4(DTp) 3(RCO 2)(L), where R=H, CH 3, C 2H 5, CH 2Cl, CCl 3, R 1C 6H 4 (R 1 is the group on the benzene ring of aromatic carboxylate), L=pyridine, CH 3CN, DMF, have been synthesized by the ligand substitution reaction. The dissociation of the loosely-coordinated ligand L from the cluster core was studied by 31p nmr. The dissociation process of L is related to the solvent, temperature, and acidity of carboxylate groups, so as to affect the solution structure and reactive properties of the cluster. The long-distance interaction between ligands RCO 2 and L is transported by Mo 3S 4 core.

关键词： 31p nmr molybdenum cluster ligand dissociation

Na_2BaMg(pO_4 )_2:synthesis, crystal structure and europium photoluminescence properties

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Journal of Rare Earths 2013年第9期31卷 849-856页

作者： Amal Boukhris Mourad Hidouri Benoit Glorieux Mongi Ben Amara UR:Inorganic Materials Faculty of ScienceUniversity of Monastir Institute for Condensed Matter Chemistry of Bordeaux CNRS University of Bordeaux I87Avenue of Dr.A.Schweitzer33608 Pessac-CedexFrance

Na2BaMg（pO4）2 was synthesized and characterized by X-ray diffraction, differential thermal analysis （DTA）, 31p nmr spectroscopy and photoluminescence measurements. This compound crystallized in the p3 ml space group of the trigonal system with the parameters of equivalent hexagonal cell a=0.5305（1） nm and c=0.6986（3） nm. The structure showed a perfect isotipysm with the mineral glaserite KaNa（SO4）2. Thus, it exhibited a lamellar framework which could be described as the stacking along the [001] direc- tion of [Mgp2O84-]∞ layers of comer sharing MgO6 polyhedra and pO4 tetrahedra. The Ba2＋ cations were located within the interlayer space, while the Na＋ ones were found in large cavities bound to the layers. The DTA analysis showed that this compound melt con- gruently at 1385 K. The 31p nmr spectrum was consistent with the presence of a single phosphorus site in the structure. Optical properties were investigated for the 5% doped Eu3＋ and Eu2＋ phases. The trivalent europium was used as a local probe, replacing bar- ium while the divalent europium was used to examine whether this material could be used as an optical applications.

关键词： phosphate 31p nmr crystal structure europium photoluminescence rare earths