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1.
A study on the curves of the exchange ratio E(%)-pH on the liquid-solid interface of the systems Zn(II) with clay minerals (Kaolinite , illite and montmorillonite), Zn(II) with hydrous ferric oxides (amorphous ferric oxide, goethite and hematite). Zn(II) with hydrous manganese oxide (y-MnOOH, manganite and 5-MnO2) etc . in seawater resulted in the discovery of new plateau type exchange ratio ?%)-pH curves not yet reported in literature. The two factors that decide the growth , decline and the change of the " plateau type " curve are : (1) the inherent characteristics of systems , which can be explained by the exchange constants i(i=1 ,2 , 3 . etc .) of interfacial stepwise ion / coordination particle exchange between liquid and solid ; and (2)The theory of interfacial stepwise ion/coordination(the amount of solid exchange reagent)particle exchange in seawater was applied to explain the experimental results of the above study and a general formula was derived for the plateau type exchange ratio E(%)-pH c 相似文献
2.
STUDY ON THE ISOTHERMS OF THE INTERACTION BETWEEN SUSPENDED PARTICLES AND Cu (Ⅱ) IN THE HUANGHE RIVER 总被引：1，自引：0，他引：1
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｖａｒｉｏｕｓｐｈｙｓｉｃａｌａｎｄｃｈｅｍｉｃａｌｒｅａｃｔｉｏｎｓｔｈａｔｏｃｃｕｒｂｅｔｗｅｅｎｔｈｅｓｕｓｐｅｎｄｅｄｐａｒｔｉｃｌｅｓ,ｓｅｄｉｍｅｎｔｓ,ｅｔｃ.ａｎｄｈｅａｖｙｍｅｔａｌｓｉｎａｎａｔｕｒａｌａｑｕａｔｉｃｓｙｓｔｅｍｐｌａｙｅｘｔｒｅｍｅｌｙｉｍｐｏｒｔａｎｔｐａｒｔｓｉｎｃｏｎｔｒｏｌｌｉｎｇｔｈｅｄｉｓｔｒｉｂｕｔｉｏｎｐａｔｔｅｒｎ,ｍｉｇｒａｔｉｏｎａｎｄｔｒａｎｓｆｏｒｍａｔｉｏｎｏｆｈｅａｖｙｍｅｔａｌｓｔｈｅｒｅ.Ｓｉｎｃｅ… 相似文献
3.
The isotherms of the interaction between the suspended particles and Cu2+, and the effects of lysine and asparaginic acid on the isotherms in the Huanghe (Yellow) River were studied by applying the
theory and method of interfacial stepwise ion/coordination particle exchange. We obtained a new stepped river isotherm, formed
by two curves joined together with a “plateau” in the middle. The adsorption equilibrium constantsK
1 andK
2 were calculated by using the isothermal equation of surface stepwise ion exchange. Amino acid in small amount promotes exchange
adsorption of the suspended particles with Cu2+. The degree of promotive action relates to the isoelectric point of amino acid. The promotive effect of lysine is bigger
than that of asparaginic acid.
Project 29361001 supported by NSFC. 相似文献
4.
Kang Xinglun 《中国海洋湖沼学报》1990,8(4):348-353
To make surface seawater flow, the shear stress of the wind blowing on the sea must overcome the work of cohesion of seawaterW
c. Oil film on the sea will drift along the wind direction so long as the shear stress of the wind overcomes the work of adhesion
between the water and the oilW
a or the work of cohesion of oil Wt,o.
Experiments bear out the theory that surface tension of seawater is more than twice that of oils generally, so that the wind
influenced drift velocity of the oil film is over two times that of the wind-driven surface current. The wind factor for surface
current in Jiaozhou Bay is 0.025, while those for the drift velocities of O-diesel oil film and the used light crude oil film
are 0.070 and 0.052 respectively.
Generally the primary factors influencing the movement velocity of oil film on the sea are current, wind, and the physicochemical
properties of the oil. The drift velocity of oil film is determined from analysis of the work of adhesion between seawater
and oil. Experiments and actual observations agree with the theoretical analysis.
Contribution No. 1831 from the Institute of Oceanology, Academia Sinica 相似文献
5.
A preliminary theoretical and experimental study was conducted on internal wave modes and their weak nonlinear resonant interaction
in a nonlinearly stratified fluid. An asymptotical solution of the modes and a dispersion relation of internal waves in a
stratified fluid with density profile
similar to that in our experiment were obtained theoretically. The resonant-interaction mechanism to 2nd order approximation
is also discussed. The resonant interaction of the 3rd and 4th mode internal waves excited by the unstable 1st mode wave is
analyzed on the basis of data obtained by conductivity probes. The resonant-interaction condition, i.e.,
,k
1+k
3+k
4=0, is examined. It is shown that the resonant instability increases with pycnocline thickness and wave maker driving frequency.
This work is supported by the National Natural Science Foundation of China. 相似文献
6.
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
7.
With the application of electronic computers, the extraction of harmonic constants from high and low waters becomes an extremely
simple process as compared with Doods’n’s technique. The phenomenon of aliasing is examined by supposing the samples are taken
at intervals of exactly 6 lunar hours. The constituents with frequencies satisfying the relation
are inseparable and the coefficient determinant of the normal equations will be singular if the heights only are used. When
the values of the first derivatives and the irregularity of the sampling are taken into consideration the condition of the
determinant is improved. Large diurnal tides can cause irregularity of sampling and so we are in favour of the separation
of the aliased constituents. For tidal current data, if the slack times are available, the results of analysis can be much
improved. The results for major constituents derived from the observed high and low waters agree satisfactorily with those
from hourly data.
This paper was published in Chinese inOcean. Limn. Sinica
17(4):318–328, 1986. 相似文献
8.
In this paper, the linear continuously stratified ntxiel of the abyssal circulation proposed by Pedlosky (1992) was emended to include the second order term - (γθm) in the vertical turbulent mixing pararneterization of - (ω‘θ‘）x = kvθxx- θxxx, in which kv is a vertical diffusion coefficient,and γ is the second order coefficient of turbulent mixing (or simply called γ-term and γ＜0 is only allcmed). The influence of the γ-tema on the baroclinic structure of the abyssal circulation driven by up-welling out of the abyss was investigated, It was found that the γ-term has a noticeable influence on thebaroclinic structure of the upwelling driven abyssal circulation. For uniform upwelling, it favors the baroelinic layering of the abyssal circulation in the eastern part of the basin, but prevents the layering in thewest. In addition, this parameter was found to decrease the vertically averaging meridional velocity of theabyssal circulation frcrn the west to the east on the southern boundary. For upwelling localized near theeastern boundary, the γ - term favors baroclinic layering of the abyssal circulation in the whole basin.Especially, on the southern boundary the γ - term could strengthen the vertically averaging meridional ve-loeity in the west, but gready weaken it in the east. The ntntel presented here might be considered as anextension of the Pedlosky baroclinic ntntel of the abyssal circulation. 相似文献
9.
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
10.
IR spectra of Cu (II)-marine solid particle systems show that Cu(II)-marine solid particle ion exchange causes a stepwise
change in the surface H-bonding hydroxyl groups on illite, montmorillonite, CaCO3, γ-AlOOH and goethite, but that this does not affect the surface free hydroxyl groups on illite, montmorillonite and CaCO3, and framework hydroxyl group on goethite and on γ-AlOOH. Over the range of Cu (II) exchange amounts in the present experiment,
four stepwise changes were discovered for the surface H-bonding hydroxyl group on illite, while two stepwise changes were
observed on the other marine solids. The interfacial stepwise ion exchange theory was first demonstrated by the above experimental
evidence. 相似文献
11.
Incubation experiments are carried out to study the exchange rates of dissolved inorganic nutrients including silicate, phosphate, ammonium, nitrite, and nitrate （^vSiO3-Si,^vPO4-P, ^vNH4-N, ^vNO2-N and ^vNO3-N） at the sediment-water interface in the Jiaozhou Bay. Major factors influencing the exchange rates are discussed in detail, which include the dissolved inorganic nutrient concentrations in porewater （Cpw）, water and clay contents, and grain size of the sediments （CH2O, Cclay and GSsed）. The results may provide insight into the dynamics of nutrient transport and the environmental capacity of nutrients in Jiaozhou Bay, and should be beneficial to solving the problems caused by excessive nutrient input this area. 相似文献
12.
This article deals with a new type of isotherm discovered in sea water systems. The characteristics of this type of isotherm
are the non-linear exponential relationship in the low concentration region and the isotherm composed of two or three “S”
curves with one or two plateaus in the middle. This isotherm cannot be expressed by the isotherm equation used in marine chemistry
at present.[7] Besides, there has been no report in literature about this type of isotherm in so far as the reaction of minor elements
on hydrous oxides is concerned. In order to explain theoretically this type of isotherm, this article suggests the use of
the theory of interfacial stepwise ion/coordination particle exchange (for simplicity, ion exchange is used herein-after)
of suspended particles to deduce a corresponding isotherm equation. Proceeding from the isotherm of this article, we made
theoretical analyses of these two characteristics as well as experiments in verification thereof. Twenty-four systems of experiments
on this new type of isotherm and isotherm equation were designed and conducted. Experiment results agree with the theory reported
here.
Project supported by the Science Fund of the Chinese Academy of Sciences. 相似文献
13.
Four kinds of polysaccharides (FA, FB, FC and FD) were extracted and purified from a red alga Furcellaria lumbricalis. Their monosaccharide composition, average molecular mass
and structural feature were determined by gas chromatography (GC), high performance gel permeation chromatography (HPGPC)
and Fourier transform infrared spectroscopy (FTIR), respectively. The results showed that FA and FB were composed of galactose
(Gal), 3,6-anhydro-galactose (AnG) and 4-sulfated-galactose (G4S), which were structurally similar to β-carrageenan and κ-carrageenan.
FC was composed of sulfated galactose and small amount of AnG, indicating that it was a hybrid-sulfated galactan. FD was composed
of α-1,4-glucose and belonged to floridean starch. The respective yields of FA, FB, FC and FD were 4.84%, 33.74%, 8.76% and
13.5%, and the corresponding
were 537 kD, 432 kD, 513 kD and 51 kD respectively. Owning to its high content (>60%) of polysaccharide, F. lumbricalis will be a good source of marine sulfated polysaccharide and shows its potential utilization in food and medicine. 相似文献
14.
Summarized results of studies on the physical and interfacial chemistry of the Huanghe estuary are presented as follows: 1.
The relationship between the exchange ratio (%) and pH for the Cu (II)-Sedi.ments of the Huanghe Estuary and that of the Cu
(II)-illite system were observed to be very similar. 2. A stepwise ion/coordination particle exchange isotherm of trace metal
in Huanghe estuary sediment was derived. 3. The ion/coordination particle exchange between trace metal and Huanghe Estuary
sediment is analogous to the interfacial chemical characteristic of illite. 相似文献
15.
Microstructure profiling measurements taken on a shallow Black Sea shelf and in Lake Banyoles and Boadella reservoir (Both in Spain) are analyzed to investigate the influence of boundary-layer-induced turbulence of various sources on mixing in the water interior. The state of turbulence in shallow waters is examined and details of microstructure data processing and error analysis are discussed. The dependence between averaged activity parameter AG and buoyancy Reynolds number Reb for the shelf turbulence indicates that for Reb < 1 the state of turbulence can be described by the fossil turbulence model, which postulates AG-Reb1/2. For Reb> 1, however, the influence of Reb on AG is weak, signifying that the buoyancy Reynolds number can no longer serve as the governing parameter for active turbulent mixing. The generation of turbulence by a one-minute long wind bursts (the Boadella reservoir) increases the averaged dissipation rate (e) of the surface mixed layer by more than 5 times (up to 3×10-6 W kg-1). The influence of the wind bursts was also traced below the ther-mocline, where turbulent patches with 相似文献
16.
Results of a series of experiments (on the adsorption of divalent metal ions by dried alginic acid, Na and Ca alginates of
different composition and block structure) conducted in this systematic study of the effects of the composition and structure
of alginates on the static adsorption equilibrium of divalent metal ions indicate that the properties of alginate adsorption
to divalent metal ions are highly different, depending not only on the cations used, but also on the form and structure of
the alginates. There is close correlation between the adsorption properties and the structure of the alginates. The selectivity
coefficient of Na alginate for Cd-Sr ion exchange tends to increase with the increase of theM/G ratio in alginate, whereas the adsorption capacity of Ca alginate for Cu2+ ion decrease with the increase of the G-block or the average length of the G-block
and the total adsorption capacity of alginic acid is found to vary in the same order as theF
MM(diad frequency) in alginate in the mixed solution of Sr2+, Ba2+ and Cd2+.
Contribution No. 2166 from the Institute of Oceanology, Chinese Academy of Sciences. 相似文献
17.
The stepwise exchange action and steric hindrance effect of organic phenols on clays in seawater 总被引：4，自引：0，他引：4
The exchange action of six types of organic phenols on clay surfaces in seawater is systematically studied in this work. The following significant conclusions are drawn from the experiments. (1) The interaction of organic phenols with montmorillonite, illite and kaolinite in seawater is monovalent anion exchage.(2) Their isotherms of stepwise exchage on clay surfaces belong to the Langmuir type or stepwise type.(3) The discovery of the"steric hindrance effects of stepwise exchange of organic phenols on clays surfaces", and revelation of an exchange mechanisrn diffeient from that in references are the greatest achieverments in this work. 相似文献
18.
This article deals with the interaction of zinc with δ−MnO2, γ−MnOOH and manganite existing in natural water systems. The mechanism of the reaction has been studied in detail. From
the fact that the “ratio of ion exchange(%)-pH” graph is an “S shaped” curve, it is possible to deduce that the chemical reaction
is of the nature of cation exchange. And since the pH range of ion exchange=4, it is possible to further deduce that the reaction
can be explained by the mechanism of monovalence cation exchange.
The main result of this article is the discovery of a new type of isotherm which has not been mentioned in previous literature
here and abroad. This isotherm cannot be represented by any presently available adsorption isotherm equations in marine chemistry.
The characteristics of this new type of isotherm are as follows: the isotherm has two “knees” and three “plateaus”, the heights
of these three “plateaus” are in the ratio 1:2:3. In order to explain theoretically our new isotherm, this article suggests
the application of the principle of interfacial stepwise ion exchange for liquid-solid distribution of minor elements on suspended
particulate matter. The corresponding isotherm equation was derived from this theory.
The results obtained in this article will be of theoretical guiding significance in the study of the marine geochemistry of
zinc.
Projects supported by the Science Fund of the Chinese Academy of Sciences. 相似文献
19.
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
20.
This paper reports the approprite ranges of Mg^2 ,Ca^2 and their ratio Mg^2 /Ca^2 in mixed seawater for rearing of Penaeus japonicus larvae,The ranges for the above three indices are 1150-1450mg/L,360-440mg/L and 2.8-3.4,respectively,the proper salinity range of mixed seawater is 22.1-33.9 obtained by mixing estuarine water and concentrated seawater. 相似文献