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1.
This paper deals with the infrared spectra of “amino acid-clay, calcium carbonate and γ-AlOOH” and “Cu(II)-clay-amino acid”
model systems, and shows that the model of the ternary surface complex is M-OHLCu (L=amino acid) for marine solid particle-Cu
(II)-amino acid. Study of the formation mechanism of the ternary surface complex shows that the specific surface area, and
especially the intrinsic acidity constant, determine whether the ternary surface complex is easily formed, and that factor,F
TSC, quantifies the relationship between the promoting effect of organics on Mt-marine solid particle ion exchange and the intrinsic acidity constant and specific surface area. 相似文献
2.
The results obtained from the Cu(II)%-pH curve of the system in the presence of added amino acid indicated that the added
amino acids of higher concentration can inhibit the Cu(II)-σ-MnO2 ion exchange and that their inhibiting effects decrease in the following sequence when the initial amino acid concentrations
are 20.00 ppm: histidine > cystine > glutamic acid > proline > alanine > glycine. The determination of amino acid in solution
performed with an amino acid analyser showed that added amino acids react chemically on the surface of the σ-MnO2 According to thermodynamic equilibria relations in the system, amino acids can be changed to amines because of their decarboxylation
on the surface of the σ-MnO2. Considering (1) the effect-inhibiting factor of amine FA(β, Ka, pH) representing the complex potential of amine with Cu(II) in solution and (2) the acidic constant of −NH
3
+
group in the amine molecule representing the ability of cation exchange of the amine with σ-MnO2, the inhibiting seqence of added amino acid of 20.00 ppm (Eq.(1)) is reasonable. Thus added amino acids do inhibit Cu(II)-σ-MnO2 ion exchange because (1) the amino acid and/ or amine, which is the decarboxylate of the corresponding amino acid, complex
with Cu(II) in solution and compete with σ-MnO2 for Cu(II); (2) the cation exchange of the amino acid and/or amine reduce the exchange site on the surface of the σ-MnO2. The results obtained from the isotherms indicated that the theory of interfacial stepwise ion exchange can be extended to
the Cu(II) σ-MnO2 ion exchange system in the presence of added amino acid. 相似文献
3.
In seawater, aside from metal elements and suspended particles, organic substances amount to about 500–2,000 ug carbon/l[8], which is not neglegible in comparison with that of minor metal elements. But in the study of the interaction of the three
constituents (metal elements, organics, and suspended particles), the effect of organics in seawater on the surface reaction
of metal element—suspended particles has usually been neglected. Recent theoretical research[1, 11] confirmed the importance of the effect of organics in seawater on the surface reaction of metal element—suspended particles.
Generally, the effect of organics on the reaction of metal ions, especially Cu(II), on a solid surface is either promotive[2] or inhibitive[7, 9]. So far the fact that organics cannot affect the surface reaction of Cu(II) ions on solids has not been reported in literature.
Our experimental results showed that none of the amino acids in seawater affect Cu(II)-goethite ion exchange under certain
experimental condition (such as amino acid of lower concentration and lower pH). It was known that the metal ion-organics
complex in a liquid competing with solids for metal ions may inhibit the surface reaction of metal ions on solids, but the
mechanism of the complex reaction of metal ions competing with solids is not known yet. In fact, the decrease of surface site-exchanging
due to the surface reaction of organics on solids is also inhibitive. It is also explained by the ion exchange isotherm of
the “amino acid-Cu(II)-geothite” system. This result further demonstrates that the theory of interfacial stepwise ion exchange
is applicable to the metal ion exchange isotherm with the presence of organic substances in the system.
Projects supported by the Science Fund of the Chinese Academy of Sciences 相似文献
4.
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5.
中国及其邻区地表气象数据预处理和网格化数值结果分析 总被引：1，自引：0，他引：1
讨论了与距离成反比和Ｋｒｉｇｉｎｇ等不同的２维插值方法在地表气象数据网格化中的应用,介绍了对中国及邻区１２００多个气象台站数据的预处理过程,对网格化后的数值结果进行了必要的可靠性分析。计算结果说明,在离散台站分布密度与网格节点分布密度大致相同的前提下,网格化处理后的区域气象数据能较好反映离散数据性质。 相似文献
6.
IGGGRACE01S模型确定的海面地形和地转流 总被引：3，自引：2，他引：1
用IGGGRACE01S、EIGENGRACE02S和EGM96地球重力场模型的前80阶分别计算出全球大地水准面,再与多颗测高卫星资料得到的平均海面高模型KMS04差分,构制出3种海面地形,并计算出相应的地转流。与Williams绘制的全球主要海流结果相比,不难看出,重力场模型IGGGRACE01S、EIGENGRACE02S的结果能清晰地显示出大尺度海洋地转流,而EGM96模型结果在赤道地带不明显。上述结果不仅显示了GRACE地球重力场模型IGGGRACE01S和EIGENGRACE02S具有较高精度探测地转流的能力,而且也表明了它们的长波精度优于EGM96模型,从应用角度展示了GRACE结果的有效性。 相似文献
7.
讨论了构造块体在球面上运动的两种运动学模型。其一称之为“完全模型”,把构造块体视为刚体,把地球近似为圆球,则块体在地表的运动可用该模型完全描述。其二称之为“平移模型”,当构造块体上的观测点不足时,通过增加约束条件,可用该模型描述块体间的相对运动。阐述了两种模型的适用范围以及确定运动参数的方法,导出了计算公式,并给出了两个算例。 相似文献
8.
This paper proposes a new method for determining the intrinsic acidity constantsK
a1
int
andK
aj
int
. The new method is a great improvement over the modified Langmuir plot method generally adopted in that determination of
these constants is not dependent on the specific surface area
of the marine solid particles. The new method was used to determineK
a1
int
,K
2a
int
and
for the main inorganic components of marine solid particles, including illite, montmorillonite, kaolinite, goethite, γ-AlOOH.
amorphous ferric oxide, δ-MnO2, manganite, SiO2 and calcium carbonate, and can facilitate the study on the effect of solution constituents, solution temperature, ionic strength,
etc. on the value of
. 相似文献
9.
宋子齐 《地球科学与环境学报》1987,(1)
本文使用一种随机模拟方法,把矿藏作为一个特定的封闭系统,以引起矿藏厚度或截面积变化的因果关系作最佳拟合,模拟计算矿藏体积和储量。同时,提供了该方法的数学模型,并编制了计算流程框图和BASlC程序。 相似文献
10.
???ò????????????EGM2008??EGM96???????????????CLS01??DNSC08??WHU2009??CNES_CLS10?????????????????????????μ???????????λ???????????????θ????????λ????????62 636 858.333 3 m 2 s -2 ?? 62 636 858.260 6 m 2 s -2??????????EGM2008??????????????λ???С??1.40 m 2 s -2????????????????????????????????? 相似文献
11.
招掖地区斑状花岗岩,即所谓郭家岭斑状花岗闪长岩的组成部分。自东向西有郭家岭体岩、南围岩体、北截岩体、上庄岩体、三山岛岩体,裸露面积约500平方公里,以岩基、岩株、岩枝等产于玲珑花岗岩的北部。班状花岗岩与金矿关系密切,许多金矿,尤其是玲珑、焦家式大型、特大型金矿直接产于其中或近接触带内。因而受到国内广大地质工作者的关注,先后做了大量的地质工作和研究工作,但长期以来对其成因、时代等认识不一,分歧较大。本文试在前几年工作的基础上并荟萃各方资料予以探讨,不当之处,敬请指正。 相似文献
12.
郭洁冰 《地球科学与环境学报》1992,(4)
曲面拟合在数学地质中应用广泛。本文讨论用多项式函数对离散点观测值进行曲面拟合的优化过程。采用Gram—Schmidt正交化方法计算实矩阵的Moore-penrose型广义逆矩阵;并给出方程组的最短最小二乘解。优化后的曲面拟合方法降低了中间计算结果中坐标值的方次,因而计算出高阶趋势面系数时精度较高,也可以得到较高的多项式趋势面方程。 相似文献
13.
SYNTHESIS AND PROPERTIES OF SULFHYDRYL CHITOSAN 总被引：1，自引：0，他引：1
A new adsorbent for heavy metal ions, sulfhydryl chitosan (S-chitosan), was produced by treatment of chitosan with sulhydryl acetic acid in the presence of sulfuric acid as a catalyst. Its structure was confrrmed by elemental analysis and FI‘-IR spectra analysis. The adsorption properties of sulthydryl chitosan for Cu(Ⅱ ), Cd(Ⅱ ), Pb(Ⅱ), Cr(Ⅲ) and Ni(Ⅱ) were investigated, and the effect of pH value on adsorption, adsorption kinetics, and selective adsorption was examined. It was shown that S-chitosan has good adsorption for Pb(Ⅱ), Cu(Ⅱ) and Cd(Ⅱ) like chitosan, is also insoluble in acid solution; has good adsorption kinetic properties for heavy metal ions; and can be used in acid solution. The adsorption capacities of S-chitosan can be affected by media acidity. The adsorbed Cu(Ⅱ) Cd(Ⅱ) and Pb(Ⅱ) could be eluted by diluted chlorhydric acid. 相似文献
14.
自“七五”以来,小秦岭区在区域地质构造特征,发展演化阶段,区域构造格局,金矿类型的系列性和序列性等诸多方面取得了不少新进展,初步建立起了小秦岭“折离-变质杂岩核”构造体系,从而为金的区域找矿、远景预测及新类型研究提供了一条全新的思路。 相似文献
15.
Niu Jiaohong Sun Chengjun Yang Bo Xie Lei Jiang Fenghua Cao Wei Chen Yan Ding Haibing Huang Yuhuan Gao Xianchi 《中国海洋湖沼学报》2023,41(1):118-137
The composition and concentration of dissolved free amino acid (DFAA) of seawater samples collected in May 2016 from the surface to the hadal zone of the northern region of the Yap Trench were analyzed by pre-column derivatization of o-phthalaldehyde. Results show that the average concentration of DFAA in the study area was 0.47±0.36 µmol/L. In different sampling stations, the concentrations of DFAA with water depth showed complex variation patterns. At the sediment-seawater interface, the concentrations of DFAA in the western side of the trench were obviously higher than that in its eastern side. In the study area, there were no significant correlations between the concentrations of DFAA and the environmental parameters such as concentrations of chlorophyll a (Chl a), dissolved oxygen (DO), pH, and dissolved inorganic nitrogen (DIN), indicating that the concentrations of DFAA in seawater of the trench are affected by many factors, such as photosynthesis, respiration, temperature, pressure, illumination, and circulation. The dominant DFAA are similar in different water layers of sampling stations, including aspartic acid (Asp), glutamic acid (Glu), glycine (Gly), and serine (Ser). The composition of different amino acids, and the relative abundance of acidic, basic, and neutral amino acids might be related to the sources and consumption of various amino acids. Nine pairs of amino acids in the DFAA showed significantly positive relationship by correlation matrix analysis, suggesting that they might share similar biogeochemical processes. The degradation index (DI) of the DFAA in seawater of the Yap Trench could reflect the degradation, source, and freshness of DFAA in the trench to some extents. This is a preliminary study of amino acids from sea surface to hadal zone in the ocean, more works shall be done in different trenches to reveal their biogeochemical characteristics in extreme marine environments.
相似文献16.
本文讨论的沈阳地区地下水化学微量组分动态特征及趋势分析,是采用统计分析的方法进行的。统计分析表明,尽管地下水中绝大部分微量组分在各井点中均能检出,但超背景及超标井点的检出率并不高,且主要分布在老城区。大部分微量组分的检出有明显的不均一性,以及重现性差,检出具有较强规律性的有六价铬、镉等少数项,并与地表排污有关。而地下水中微量组分污染的特征是,绝大部分组分呈现出明显的点源污染。作者根据有机污染的指标化学需氧量采用相关分析方法,探讨它与总有机氮和总有机炭的关系,凡有机污染日趋严重的地段,地下水的化学需氧量就愈高。在动态趋势分析上,采用数字模型方法以六价铬为例,进行了单井的预测分析,并在此基础上,提出了控制污染发展的环境管理目标值。 相似文献
17.
18.
卢万年 《地球科学与环境学报》1992,(2)
本文对李四光先生提出的山字型构造受力模型的选择、面力和解析解的关系等进行了探讨,并研究了另一种受力模型的面力和解析解的变化规律。通过对这两种受力模型合理性的分析,明确指出较为合理的受力模型。 相似文献
19.
JI Zhongqiang JIN Haiyan STEIN Ruediger LI Zhongqiao BAI Youcheng LI Hongliang ZHANG Yang CHEN Jianfang 《中国海洋大学学报(英文版)》2019,(3)
The organic matter(OM) preserved in Arctic Ocean sediments is of great importance to the global carbon budget. However, works that apply multiple proxies to determine the distribution and concentration of organic carbon(OC) in the surface sediments of the northern Bering and Chukchi Seas remain limited. Here a multiproxy approach based on bulk OM parameters and the branched vs. isoprenoid tetraether(BIT) index was used to investigate the distribution and sources of OM in the surface sediments of the northern Bering and Chukchi Seas. Binary and ternary mixing models were applied to trace the contribution of different OC sources to the total OC in the study area. The ?13 C values of the sediments provided by the binary model showed that the proportion of terrestrial OC fell in the range of 27.4%-79.8%(46.2% on average). The BIT index returned the lowest fraction(4.8%-27.3%, 12.0% on average). The ternary mixing model was employed to determine the plant-, soil-, and marine-derived fractions of the total OM. The ternary model showed that 11.5% ? 6.3%, 31.4% ? 9.5%, and 57.1% ? 12.4% of OM in the sediment of the study area was derived from soil, plants, and marine sources, respectively. The differences in OM composition between the west and east sides of the Chukchi Sea were controlled by OM inputs from key water masses(i.e., Anadyr Water and Alaska Coastal Water), river discharge, and the nutrient supply from the Pacific inflow that supports marine productivity. 相似文献
20.
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