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1.
Radon volatilization mechanism into the gas phase was hypothesized to explain the anomalous decline in groundwater radon precursory to the 2003 M W = 6.8 Chengkung earthquake in Taiwan. We initiated the monitoring of both radon and methane in the groundwater since November 2007 at well D1 in the Antung hot spring. The mechanism of in-situ radon volatilization has been corroborated by the simultaneous anomalous declines in groundwater-dissolved radon and methane precursory to the 2008 M W 5.0 Antung earthquake.  相似文献   

2.
The active Chihshang fault in the southern segment of longitudinal valley of eastern Taiwan is part of the suture boundary between the Eurasia plate and the Philippine Sea plate. Radon anomalies in groundwater were recorded prior to three major earthquakes—(1) 2003 M w = 6.8 Chengkung, (2) 2006 M w = 6.1 Taitung, and (3) 2008 M w = 5.4 Antung. The epicenters were located 24, 52, and 13 km, respectively, from the radon-monitoring well (D1) in the Antung hot spring about 3 km southeast of the Chihshang fault. Prior to the three major earthquakes, radon decreased from background levels of 787 ± 42, 762 ± 57, and 700 ± 57 pCi/L to minima of 326 ± 9, 371 ± 9, and 480 ± 43 pCi/L, respectively. Based on the radon volatilization model and the rock dilatancy model, this paper correlates the observed radon minima with local earthquake magnitude and crust strain. The correlation is a useful means of forecasting local disastrous earthquakes in the southern segment of longitudinal valley of eastern Taiwan.  相似文献   

3.
Some thermal infrared anomalies on the earth’s surface are omens of stronger earthquakes, and have a close relationship with the stress fields. Satellite-based remote sensing is an important means of monitoring and researching this phenomenon. The M S 7.3 Yutian earthquake in Xinjiang on March 20, 2008 and the M S 8.0 Wenchuan earthquake in Sichuan on May 12, 2008 both happened in the Qinghai–Tibet Plateau, China, with epicenters more than 2,000 km apart. The two events, however, were a production of an identical stress field in different developing phases. Prior to the M S 7.3 Yutian earthquake, a large-scale abnormal temperature rise not only covered the epicenter of the forthcoming Yutian earthquake, but also arrived at the epicenter of the farther Wenchuan earthquake. The revolving elliptic stress thermal field reflecting earthquake gestation moved from the west to the east of the Wenchuan epicenter at the time of the Yutian event occurrence. The rotation of the calefactive ellipses and belts prior to the two strong events agreed with the stress field, the focal mechanism, and modality and mechanism property of the ruptures in the crustal surface induced by the events. It should be a reflection of the partial mantle uprush and rotation.  相似文献   

4.
The compressibility at room temperature and the thermal expansion at room pressure of two disordered crystals (space group C2/c) obtained by annealing a natural omphacite sample (space group P2/n) of composition close to Jd56Di44 and Jd55Di45, respectively, have been studied by single-crystal X-ray diffraction. Using a Birch–Murnaghan equation of state truncated at the third order [BM3-EoS], we have obtained the following coefficients: V 0 = 421.04(7) Å3, K T0 = 119(2) GPa, K′ = 5.7(6). A parameterized form of the BM3 EoS was used to determine the axial moduli of a, b and c. The anisotropy scheme is β c  ≤ β a  ≤ β b , with an anisotropy ratio 1.05:1.00:1.07. A fitting of the lattice variation as a function of temperature, allowing for linear dependency of the thermal expansion coefficient on the temperature, yielded αV(1bar,303K) = 2.64(2) × 10−5 K−1 and an axial thermal expansion anisotropy of α b  ≫ α a  > α c . Comparison of our results with available data on compressibility and thermal expansion shows that while a reasonable ideal behaviour can be proposed for the compressibility of clinopyroxenes in the jadeite–diopside binary join [K T0 as a function of Jd molar %: K T0 = 106(1) GPa + 0.28(2) × Jd(mol%)], the available data have not sufficient quality to extract the behaviour of thermal expansion for the same binary join in terms of composition.  相似文献   

5.
Phragmites australis has been invading Spartina-alterniflora-dominated salt marshes throughout the mid-Atlantic. Although, Phragmites has high rates of primary production, it is not known whether this species supports lower trophic levels of a marsh food web in the same manner as Spartina. Using several related photochemical and biological assays, we compared patterns of organic matter flow of plant primary production through a key salt marsh metazoan, the ribbed mussel (Geukensia demissa), using a bacterial intermediate. Dissolved organic matter (DOM) was derived from plants collected from a Delaware Bay salt marsh and grown in the laboratory with 14C-CO2. Bacterial utilization of plant-derived DOM measured as carbon mineralization revealed that both species provided bioavailable DOM to native salt marsh bacteria. Total carbon mineralization after 19 days was higher for Spartina treatments (36% 14CO2 ± 3 SE) compared with Phragmites treatments (29% ±2 SE; Wilcoxon–Kruskal–Wallis rank sums test, P < 0.01). Pre-exposing DOM to natural sunlight only enhanced or decreased bioavailability of the DOM to the bacterioplankton during initial measurements (e.g., 7 days or less) but these differences were not significant over the course of the incubations. Mixtures of 14C-labeled bacterioplankton (and possibly organic flocs) from 14C-DOM treatments were cleared by G. demissa at similar rates between Spartina and Phragmites treatments. Moreover, 14C assimilation efficiencies for material ingested by mussels were high for both plant sources ranging from 74% to 90% and not significantly different between plant sources. Sunlight exposure did not affect the nutritional value of the bacterioplankton DOM assemblage for mussels. There are many possible trophic and habitat differences between Spartina- and Phragmites-dominated marshes that could affect G. demissa but the fate of vascular plant dissolved organic carbon in the DOM to bacterioplankton to mussel trophic pathway appears comparable between these marsh types.  相似文献   

6.
This paper examines how perennial Aster tripolium and annual Salicornia procumbens salt marshes alter the biomass, density, taxon diversity, and community structure of benthic macrofauna, and also examines the role of elevation, sediment grain size, plant cover, and marsh age. Core samples were collected on a fixed grid on an intertidal flat in the Westerschelde estuary (51.4° N, 4.1° E) over 5 years (2004–2008) of salt marsh development. In unvegetated areas, macrobenthic biomass, density, and taxon diversity were highest when elevation was highest, benthic diatoms were most abundant, and sediment median grain size was smallest. In contrast, in salt marsh areas, macrobenthic biomass and taxon diversity increased with median grain size, while the effects of elevation and diatom abundance on macrobenthic biomass, density, and diversity were not significant. In fine sediments, macrofaunal community structure in the salt marsh was particularly affected; common polychaetes such as Nereis diversicolor, Heteromastus filiformis, and Pygospio elegans had low abundance and oligochaetes had high abundance. Marsh age had a negative influence on the density of macrofauna, and A. tripolium stands had lower macrofaunal densities than the younger S. procumbens stands. There were no significant effects of marsh age, plant cover, and vegetation type on macrobenthic biomass, taxon diversity, and community structure. The results highlight that ecosystem engineering effects of salt marsh plants on macrofauna are conditional. Organic enrichment of the sediment and mechanical hindering of macrofaunal activity by plant roots are proposed as plausible mechanisms for the influence of the salt marsh plants on macrofauna.  相似文献   

7.
To test whether invasive Spartina alterniflora marshes were functionally equivalent to native Scirpus mariqueter marshes, the present study used bottomless lift nets (20 m2) during 12 high-tide events from August to October 2008 to compare nekton densities and biomass between the two marsh types in the Dongtan wetland. A total of eight species of fish, two species of shrimp, and three species of crab were collected. So-iny mullet Chelon haematocheilus, keeled mullet Liza carinata, Asian freshwater goby Acanthogobius ommaturus, and ridge-tail prawn Exopalaemon carinicauda dominated samples from the two marsh types and accounted for over 90% of the total catch. There were significantly greater densities and biomass (p < 0.05) of total nekton (all species combined) and two mullets (C. haematocheilus and L. carinata) in S. alterniflora marshes than in S. mariqueter marshes in August 2008, while no significant differences (p > 0.05) between the two marsh types were observed for densities and biomass of any species or total nekton in September and October 2008. Non-metric multidimensional scaling ordination did not show clear separation of samples between the two marsh types (r = 0.071, p = 0.159). Furthermore, there were no habitat-specific differences (p > 0.05) in the size distributions of the three numerically dominant species (C. haematocheilus, L. carinata, and A. ommaturus). We concluded that S. alterniflora marshes were utilized by nekton in a fashion similar to their utilization of native S. mariqueter marshes under similar physical conditions.  相似文献   

8.
The Asian shore crab, Hemigrapsus sanguineus, is a recent and particularly successful introduction to the east coast of the USA. Little research has been done on the utilization of Asian shore crabs for food by native species, a potential form of biocontrol. Over a 4-year period, we examined the gut contents of cogeners, Fundulus heteroclitus and Fundulus majalis, collected from two embayments in western Long Island Sound for the presence of juvenile H. sanguineus. Frequency (percent) of occurrence of food items in the guts of both species varied over year and study site. Asian shore crabs were consumed more often by F. heteroclitus than by F. majalis, but predation pressure by both species was low. Only 13% of F. heteroclitus and 7.7% of F. majalis found with food in their guts had ingested Asian shore crab remains. Of those, 1/3 had consumed whole crabs; the rest had only autotomized appendages in their guts. The mean carapace width of juvenile Asian shore crabs ingested by F. heteroclitus was 3.59 ± 2.22 mm (N = 33). Results of our study on killifish predation support the hypothesis that H. sanguienus abundance is partly explained by reduced impact of native predators (i.e., the “enemy release hypothesis”). Predation pressure of other potential enemies on both planktonic and benthic stages of the Asian shore crab must be investigated, however, to understand the full impact of predation on H. sanguineus population dynamics.  相似文献   

9.
To offer an insight into the toxicity of nanomaterials (NM) on the growth of bacteria, Escherichia coli (E. coli), Bacillus subtilis (B. subtilis) and Agrobacterium tumefaciens (A. tumefaciens) were exposed to nano-Au, nano-Ag, nano-Fe and fullerene (C60) in this study. As an effective bactericide, nano-Ag induced high toxicity on these three bacteria; C60 could inhibit their growth; however, B. subtilis and E. coli could recover as exposure time extended. Nano-Au and nano-Fe had hardly any effect on three bacteria. A. tumefaciens showed the lowest resistance and slowest growth rate during exposure. Images obtained by scanning electron microscope (SEM) revealed that nano-Ag could cause damage to the cell structure of three bacteria at 1 μg/mL. Slight damage on E. coli was found when exposed to C60, whereas no obvious physical damage was found after exposure to nano-Au or nano-Fe. It is assumed that surface activities of NM might be responsible for the different toxic effects on these bacteria.  相似文献   

10.
The thermoelastic behaviour of anthophyllite has been determined for a natural crystal with crystal-chemical formula ANa0.01 B(Mg1.30Mn0.57Ca0.09Na0.04) C(Mg4.95Fe0.02Al0.03) T(Si8.00)O22 W(OH)2 using single-crystal X-ray diffraction to 973 K. The best model for fitting the thermal expansion data is that of Berman (J Petrol 29:445–522, 1988) in which the coefficient of volume thermal expansion varies linearly with T as α V,T  = a 1 + 2a 2 (T − T 0): α298 = a 1 = 3.40(6) × 10−5 K−1, a 2 = 5.1(1.0) × 10−9 K−2. The corresponding axial thermal expansion coefficients for this linear model are: α a ,298 = 1.21(2) × 10−5 K−1, a 2,a  = 5.2(4) × 10−9 K−2; α b ,298 = 9.2(1) × 10−6 K−1, a 2,b  = 7(2) × 10−10 K−2. α c ,298 = 1.26(3) × 10−5 K−1, a 2,c  = 1.3(6) × 10−9 K−2. The thermoelastic behaviour of anthophyllite differs from that of most monoclinic (C2/m) amphiboles: (a) the ε 1 − ε 2 plane of the unit-strain ellipsoid, which is normal to b in anthophyllite but usually at a high angle to c in monoclinic amphiboles; (b) the strain components are ε 1 ≫ ε 2 > ε 3 in anthophyllite, but ε 1 ~ ε 2 ≫ ε 3 in monoclinic amphiboles. The strain behaviour of anthophyllite is similar to that of synthetic C2/m ANa B(LiMg) CMg5 TSi8 O22 W(OH)2, suggesting that high contents of small cations at the B-site may be primarily responsible for the much higher thermal expansion ⊥(100). Refined values for site-scattering at M4 decrease from 31.64 epfu at 298 K to 30.81 epfu at 973 K, which couples with similar increases of those of M1 and M2 sites. These changes in site scattering are interpreted in terms of Mn ↔ Mg exchange involving M1,2 ↔ M4, which was first detected at 673 K.  相似文献   

11.
Electron paramagnetic resonance (EPR) study of single crystals of chromium-doped forsterite grown by the Czochralski method in two different research laboratories has revealed, apart from the known paramagnetic centers Cr3+(M1), Cr3+(M2) and Cr4+, a new center \textCr 3+ (M 1)-V\textMg 2+ (M 2) {\text{Cr}}^{ 3+ } (M 1){-}V_{{{\text{Mg}}^{ 2+ } }} (M 2) formed by a Cr3+ ion substituting for Mg2+ at the M1 structural position with a nearest-neighbor Mg2+ vacancy at the M2 position. For this center, the conventional zero-field splitting parameters D and E and the principal g values and A values of the 53Cr hyperfine splitting have been determined as follows: D = 33.95(3) GHz, E = 8.64(1) GHz, g = [1.9811(2), 1.9787(2), 1.9742(2)], A = [51(3), 52(2), 44(3)] MHz. The center has been identified by comparing EPR spectra with those of the charge-uncompensated ion Cr3+(M1) and the ion pair Cr3+(M1)–Li+(M2) observed in forsterite crystals codoped with chromium and lithium. It has been found that the concentration of the new center decreases to zero, whereas that of the Cr3+(M1) and Cr3+(M1)–Li+(M2) centers increases with an increase of the Li content from 0 up to ~0.03 wt% (at the same Cr content ~0.07 wt%) in the melt. The known low-temperature luminescence data pertinent to the centers under consideration are also discussed.  相似文献   

12.
The Andaman-Sumatra subduction zone is seismically one of the most active and complex subduction zones that produced the 26 December 2004 mega thrust earthquake (Mw 9.3) and large number of aftershocks. About 8,000 earthquakes, including more than 3,000 aftershocks (M ≥ 4.5) of the 2004 earthquake, recorded during the period 1964–2007, are relocated by the EHB method. We have analysed this large data set to map fractal correlation dimension (Dc) and frequency-magnitude relation (b-value) characteristics of the seismogenic structures of this ~3,000-km-long mega thrust subduction zone in south-east Asia. The maps revealed the seismic characteristics of the Andaman-Sumatra-Java trenches, West Andaman fault (WAF), Andaman Sea Ridge (ASR), Sumatra and Java fault systems. Prominent N–S to NW–SE to E–W trending fractal dimension contours all along the subduction zone with Dc between 0.6 and 1.4 indicate that the epicentres mostly follow linear features of the major seismogenic structures. Within these major contours, several pockets of close contours with Dc ~ 0.2 to 0.6 are identified as zones of epicentre clusters and are inferred to the fault intersections as well as asperity zones along the fault systems in the fore arc. A spatial variation in the b-value (1.2–1.5) is also observed along the subduction zone with several pockets of lower b-values (1.2–1.3). The smaller b-value zones are corroborated with lower Dc (0.5–0.9), implying a positive correlation. These zones are identified to be the zones of more stress or asperity where rupture nucleation of intermediate to strong magnitude earthquakes occurred.  相似文献   

13.
We have obtained 26 372 CCD frames in the B, V, and I c filters for 81 RR Lyrae stars in 2008–2010, using the 76-cm telescope of the South African Astronomical Observatory and the 40-cm telescope of the Cerro Armazones Observatory, North Catholic University (Chile) using an SBIG ST-10XME CCD camera. For 12 of these RR Lyrae stars, we also obtained 337 brightness measurements in the B and V bands in 2000–2001 using the 60-cm telescope of the High Altitude Mt. Maidanak Observatory (Republic of Uzbekistan). We present tables of observations, light curves, and improved light-curve elements for all these RR Lyrae stars. The Blazhko effect was detected for SU Hor.  相似文献   

14.
The saltmarsh topminnow (Fundulus jenkinsi) is federally listed as a Species of Concern due to a its rarity, impacts from human activities, and lack of information on its biology and ecology. From 2007 through 2008, we used Breder traps to fish the marsh edge on a falling tide in four regions from Louisiana through the Florida panhandle during winter, spring, and summer periods. Out of 2,108 Breder traps deployed, 661 F. jenkinsi were collected as far east as Escambia Bay, Florida, with Weeks Bay, National Estuarine Research Reserve (NERR), Alabama, yielding the highest F. jenkinsi abundance. Principal component analysis (PCA) was used to ordinate physical–chemical data into two meaningful components: a geomorphic axis (water depth, bank slope, and plant stem density) and a seasonal/spatial axis of species occurrence (water temperature, salinity, and turbidity). PCA showed a higher mean catch-per-unit-effort (CPUE) in environments comprised of low to moderate stem density (<25 stems/0.25 m−2), depth (<25 cm), bank slope (<15°), turbidity (<30 NTU), and salinity (<16) coupled with spring and early summer water temperatures (>15°C). F. jenkinsi CPUE was significantly higher in Spartina cynosuroides marsh edge compared with five other habitat types, even though it was one of the least sampled habitats. This species appears to be collected more frequently and in higher CPUE in small dendritic creeks off of main channels than suggested by our previous work in main channel edge habitat. This suggests that small creeks are important vectors for marsh access and supports the value of the dendritic nature of salt marshes to marsh residents.  相似文献   

15.
The Green Valley Mine in Indiana was abandoned in 1963 after 15 years of coal mining. Reclamation began in 1994 and ended in 1999 with the dense planting of twelve different tree species. By 2006, only green ash (Fraxinus pennsylvanica Marsh.) and black locust (Robinia pseudoacacia L.) had survived in any significant numbers. Given the acid mine drainage found at the site, we sought to determine whether element toxicity originating from mine waste was responsible for the extirpation of the trees. Leaf samples taken from 125 mine trees and 29 control trees were acquired and assayed for 41 element concentrations using inductively coupled plasma mass spectrometry (ICPMS). Except for sodium, there was no compelling evidence to indicate that toxic elemental levels were responsible for the widespread tree deaths. In addition to sodium toxicity, we suspect that micronutrient deficiency was a primary factor explaining the extirpation of trees at the mine.  相似文献   

16.
To investigate environmental variability during the late Holocene in the western Gulf of Maine, USA, we collected a 142-year-old living bivalve (Arctica islandica) in 2004, and three fossil A. islandica shells of the Medieval Warm Period (MWP) and late MWP / Little Ice Age (LIA) period (corrected 14CAMS = 1030 ± 78 ad; 1320 ± 45 ad; 1357 ± 40 ad) in 1996. We compared the growth record of the modern shell with continuous plankton recorder (CPR) time-series (1961–2003) from the Gulf of Maine. A significant correlation (r 2 = 0.55; p < 0.0001) exists between the standardized annual growth index (SGI) of the modern shell and the relative abundance of zooplankton species Calanus finmarchicus. We therefore propose that SGI data from A. islandica is a valid proxy for paleo-productivity of at least one major zooplankton taxa. SGIs from these shells reveal significant periods of 2–6 years (NAO-like) based on wavelet analysis, multitaper method (MTM) analysis and singular spectrum analysis (SSA) during the late Holocene. Based on established physical oceanographic observation in the Gulf of Maine, we suggest that slope water variability coupled with North Atlantic Oscillation (NAO) dynamics is primarily responsible for the observed SGI variability. Special Issue: AGU OS06 special issue “Ocean’s role in climate change—a paleo perspective”.  相似文献   

17.
The M w 7.8 2015 Gorkha earthquake and its aftershocks significantly impacted the lives and economy of Nepal. The consequences of landslides included fatalities, property losses, blockades of river flow, and damage to infrastructural systems. Co-seismic landslides triggered by this earthquake were significantly widespread and pose a major geodisaster. There were tens of thousands of landslides triggered by the earthquake, majority of which were distributed in between the epicenter of the main shock and the M w 7.3 aftershock. Although 14,670 landslides triggered by this earthquake were identified, only approximately 23% of them were of moderate to large scale with areas greater than 100 m2. Of the moderate- to large-scale landslides identified, just over 90% were triggered by the main shock and smaller aftershocks prior to the major (M w 7.3) aftershock, while nearly 10% were triggered by the ground shaking induced by the major aftershock. Moreover, the number of landslides triggered by the 2015 Gorkha earthquake, specifically by the main shock, was slightly more than the expected number of landslides for the recorded maximum peak ground acceleration (PGA) in comparison to the co-seismic landslides triggered by 26 earthquakes. Over 90% of those moderate- to large-scale landslides were concentrated within the estimated fault rupture surface. Majority of these moderate- to large-scale landslides were disrupted failures with over 96% of which were classified as earth falls. However, the majority of small-scale landslides were rock or boulder falls. The most number of moderate- to large-scale landslides were triggered in the slate, shale, siltstone, phyllite, and schist of the Lesser Himalayan formation followed by an equally significant number in both schist, gneiss, etc. of the Higher Himalayan formation and the phyllite, metasandstone, schist, etc. of the Lesser Himalayan formation. The sizes (i.e., areas) of the landslides were lognormally distributed, with a mode area of 322.0 m2. Slope inclinations of the moderate- to large-scale landslides followed a normal distribution with a mean slope inclination of 32.6° and standard deviation of 13.5°. There exists a strong correlation between the number of landslides and the peak ground acceleration within the study area, specific for different geological formations.  相似文献   

18.
Iron and phosphorus limitation and their combined effects on the growth and development of Prorocentrum micans Ehrenberg (Dinophyceae) and Cryptomonas sp. (Cryptophyceae) have been studied. The growth status of these algae at different Fe and P levels is quantitatively analyzed through lab-culture experiments. Results show that Fe starvation can misalign chloroplast lamellas, and metamorphose and twist thylakoid, leading to a retarded growth rate. The combined effects of Fe and P can accelerate their growth, and an optimum culture condition to maintain the maximum growth rate is a combination of 0.05 μM Fe and 50 μM P. Algal uptake of Fe and P are synergistic. Their cellular concentrations bear significant correlations (r = 0.9979 for Cryptomonas sp. and 0.9938 for P. micans; P < 0.01) and correspondingly the molar P:Fe ratios are ∼160:1 and ∼356:1, respectively. These findings will provide novel insights for revealing the crucial factors controlling the occurrence of algal blooms.  相似文献   

19.
The feeding behavior of three species of mussels, the native Ischadium recurvum and the invasives Mytella charruana and Perna viridis, was studied in an invaded ecosystem in Florida (USA). In situ feeding experiments using the biodeposition method were performed along a salinity gradient in four different locations along the St. Johns River. Water characteristics, such as salinity, temperature, dissolved oxygen, and seston loads, were recorded to identify relationships between these variables and the feeding behavior of the mussels. Feeding behavior of the species varied by study site. Clearance, filtration, organic ingestion, and absorption rates of I. recurvum were negatively affected by salinity. For the invasive mussel, M. charruana, rejection was positively related to salinity while total ingestion, organic ingestion, and absorption rates were positively related to the percentage of organic matter in the seston. For P. viridis, total and organic ingestion rates were negatively affected by salinity but positively affected by total particulate matter. Condition indices for P. viridis and M. charruana were 13.16?±?0.64 and 6.63?±?0.43, respectively, compared to 4.82?±?0.41 for the native species I. recurvum, indicating that these mussels are well adapted to the environmental conditions in the area. This study indicates that the three species have different preferred habitats because of their specific responses to water characteristics. Thus, the invasive mussels will not totally occupy the niche of the native mussel in Florida despite overlapping zones. These data may help identify potential invaded areas and understand the extent of the invasion.  相似文献   

20.
Summary The complexation of aluminium(III) and silicon(IV) was studied in a simplified seawater medium (0.6 M Na(Cl)) at 25 °C. The measurements were performed as potentiometric titrations using a hydrogen electrode with OH − ions being generated coulometrically. The total concentrations of Si(IV) and Al(III) respectively [Si tot ] and [Al t ot], and −log[H +] were varied within the limits 0.3 < [Si tot ] < 2.5 mM, 0.5 < [Al tot ] < 2.6 mM, and 2 ≤ -log[H +] ≤ 4.2. Within these ranges of concentration, evidence is given for the formation of an AlSiO(OH) 3 2+ complex with a formation constant log β1,1-1 = −2.75 ± 0.1 defined by the reaction Al 3++Si (OH)4 ↔ AlOSi(OH) 3 2+ +H + An extrapolation of this value to I=0 gives log β1,1-1 = −2.30. The calculated value of log K (Al 3++SiO(OH) 3 − ↔ AlOSi(OH) 3 2+ ) = 6.72 (I=0.6 M) can be compared with corresponding constants for the formation of AlF 2+ and AlOH 2+ , which are equal to 6.16 and 8.20. Obviously, the stability of these Al(III) complexes decreases within the series OH −>SiO(OH) 3 −  > F −  相似文献   

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