用海盐“盐差”发电

科学研究证明,两种含盐量不同的海水在同一容器中,会由于盐类离子的扩散而产生化学电位差能。同时,利用一定的转换方式,可以使这种化学电位差能转换成为电能。近年来迅速发展的海洋盐差发电技术,就是利用这种原理来进行工作。

Calculation of saturation in carbonate reservoirs based on electrical efficiency

We derived an equation for saturation in carbonate reservoirs based on the electrical efficiency model in the case of lacking core data. Owing to the complex pore structure and strong heterogeneity in carbonate reservoirs, the relation between electrical efficiency and water porosity is either complex or linear. We proposed an electrical efficiency equation that accounts for the relation between electrical efficiency and water porosity. We also proposed a power-law relation between electrical efficiency and deep-formation resistivity and analyzed the factors controlling the error in the water saturation computations. We concluded that the calculation accuracy of the electrical efficiency is critical to the application of the saturation equation. The saturation equation was applied to the carbonate reservoirs of three wells in Iraq and Indonesia. For relative rock electrical efficiency error below 0.1, the water saturation absolute error is also below 0.1. Therefore, we infer that the proposed saturation equation generally satisfies the evaluation criteria for carbonate reservoirs.

Response of Two Jerusalem Artichoke (Helianthus tuberosus)Cultivars Differing in Tolerance to Salt Treatment

To explore genetic variability for two Jerusalem artichoke cultivated with 75% seawater irrigation for six years） and N7 （Helianthus tuberosus） cultivars, N1 （the sixth-generation （a general variety）, a experiment was conducted to study the changes in physiological attributes under different concentrations （0%, 10% and 25% of seawater concentration in greenhouse and 0%, 30% and 50% of seawater concentration in the field） of seawater salinity stress. In the greenhouse experiment, decreases of dry growth rate, but increases of dry matter percentage and membrane injury occurred in both the genotypes at 10% and 25% seawater treatments, although lesser cell membrane damage was observed in N1 than N7. N1 accumulated greater contents of Na^＋, Cl^-, soluble sugar and proline in leaves compared with NT. In the field experiment, the yields of shoot, root and tuber, and the contents of total-sugar and inulin in tubers of N1 were higher than those of N7. Lesser degree of salt injury in N1 indicated that the relatively salt-tolerant cultivar had higher K^＋/Na^＋ ratio, lower Na^＋/Ca^2＋ ratio, and the salt-induced enhancement of osmotic adjustment.

Structures of Silk Fibers Grafted with Hexafluorobutyl Methacrylate

The relationship between the graft yield and the effect of hexafiuorobutyl methacrylate graft treatment on the structural changes of the silk fibers was studied on the basis of the results of scanning electron micrograph photographs （SEM）, infrared spectroscopy （IR）, Raman spectrum, wide-angle X-ray diffraction patterns （WAXD）, nuclear magnetic resonance（NMR） and amion acid analysis. The results showed that the crystalline regions of grafted fibers were hardly affected and the fiber fission occurred on the cross sections of grafted fibers. The surface of fibers was covered with a high polymer film. The Raman spectrum showed there was little change in the conformation of grafted fibers which mainly remained β-sheet conformation. The IR of the grafted silk fibers showed new absorption of bands occurred which belonged to the stretching-vibrationabsorption-peak bands of Vo-o and VC-F of aliphatic ester species. The CF3-, -CF2- and -CFH- grafted silk macromodecul were verified in the NMR spectrum. The amion acid analysis indicated fluoride monomers were inclined to graft with TYR, ARG and CLU silk fibers.

A method for correcting regional bias in SMOS global salinity products

Soil Moisture and Ocean Salinity （SMOS） Level 3 （L3） sea surface salinity （SSS） products are provided by the Barcelona Expert Centre （BEC）. Strong biases were observed on the SMOS SSS products, thus the data from the Centre Aval de Traitement des Donnees SMOS （CATDS） were adjusted for biases using a large-scale correction derived from observed differences between the SMOS SSS and World Ocean Atlas （WOA） climatology data. However, this large-scale correction method is not suitable for correcting the large gradient of salinity biases. Here, we present a method for the correction of SSS regional bias of the monthly L3 products. Based on the stable characteristics of the large SSS biases from month to month in some regions, corrected SMOS SSS maps can be obtained from the monthly mean values after removing the regional biases. The accuracy of the SMOS SSS measurements is greatly improved, especially near the coastline, at high latitudes, and in some open ocean regions. The SMOS and ISAS SSS data are also compared with Aquarius SSS to verify the corrected SMOS SSS data. The correction method presented here only corrects annual mean biases. The measurement accuracy of the SSS may be improved by considering the influence of atmospheric and ocean circulation in different seasons and years.

Enhancement of Superoxide Dismutase and Catalase Activities and Salt Tolerance of Euhalophyte Suaeda salsa L. by Mycorrhizal Fungus Glomus mosseae

Arbuscular mycorrhizal （AM）-mediated plant physiological activities could contribute to plant salt tolerance. However, the biochemical mechanism by which AM fungi enhance salt tolerance of halophytie plants is unclear. A pot experiment was conducted to determine whether salt tolerance of the C3 halophyte Suaeda salsa was enhanced by the AM fungus Glomus rnosseae. When 60-day-old S. salsa seedlings were subjected to 400 mmol L-1 NaC1 stress for 35 days, plant height, number of leaves and branches, shoot and root biomass, and root length of G. mosseae-colonized seedlings were significantly greater than those of the nonmycorrizal seedlings. Leaf superoxide dismutase （SOD） activity at all sampling times （weekly for 35 days after salt stress was initiated） and leaf catalase （CAT） activity at 2 and 3 weeks after salt stress was initiated were also significantly enhanced in G. mosseae-colonized S. salsa seedlings, while the content of leaf malondialdehyde （MDA）, a product of membrane lipid peroxidation, was significantly reduced, indicating an alleviation of oxidative damage. The corresponding leaf isoenzymes of SOD （Fe-SOD, Cu/Zn-SOD1, and Cu/Zn-SOD2） and CAT （CAT1 and CAT2） were also significantly increased in the mycorrhizal seedlings after 14 days of 400 mmol L-1 NaC1 stress. Our results suggested that G. rnosseae increased salt tolerance by increasing SOD and CAT activities and forming SOD and CAT isoforms in S. salsa seedlings.

Holocene slip rate and paleoearthquake records of the Salt Lake segment of the Northern Zhongtiaoshan Fault, Shanxi Province

The Northern Zhongtiaoshan Fault is a major deep fault at the southern margin of the Yuncheng Basin. There have been few studies on the fault, and the historical earthquakes are few and weak. However, the intensity of activity on the fault should never be underestimated. Through interpretations of aerial images, topography measurements and excavation of trenches, this paper studied the fault distribution, the surface deformation and the activity of the normal fault south of Salt Lake near the city of Yuncheng. By tracing faults in the three trenches, it was found that there had been at least three large paleoseismic events, at 1–3.5, 3.6–4.4 and 7.4–8.8 ka BP. Employing 14 C dating, we determined the same gravel layers in the uplifted side and downthrown side. Making differential Global Positioning System measurements of the vertical difference and topographic profile, we obtained the mean slip rate of the Northern Zhongtiaoshan Fault since 24.7 ka BP(0.75±0.05 mm/a). Using the results of relevant studies, we calculated the possible vertical fault displacement of one earthquake(2.35 m) and obtained the recurrence interval of characteristic earthquakes as 2940–3360 a after dividing the displacement by the mean slip rate.

Differential expression of salt tolerance related genes in Brassica campestris L. ssp. chinensis (L.) Makino var. communis Tsen et Lee

We examined salt tolerance responsive genes in Pak-choi under salt stress and analyze their potential function. The LRNA differential display was used to screen the transcript derived fragments （TDFs） related to salinity tolerance in tolerant and Loderately tolerant Pak-choi germplasm. Seventy-eight primer combinations generated 101 differential eDNA fragments, which ere divided into 10 expression types. Seven cDNA sequences （GenBank accession Nos. DQ006915-DQ006921） obtained and ,~quenced were highly homologous to some known expression genes or the genes related to the signaling pathways in plants under ifferent abiotic stress.

Phase transitions in two organic salts based on 1,5-naphthalenedisulfonate

Two phase transition compounds,diethylammonium 1,5-naphthalenedisulfonate(1)and cyclohexylammonium 1,5-naphthalenedisulfonate(2),were screened from a series of organic salts based on 1,5-naphthalenedisulfonate.The phase transition behaviors were studied by differential scanning calorimetry,single-crystal X-ray analysis and dielectric measurements.Compounds 1 and 2 undergo phase transitions at about 202 and 148 K,respectively,accompanied by distinct dielectric changes.The origin of the phase transitions was ascribed to motional changes of the cations in the crystal lattices.