125 resultados para Water-soluble ions


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Blends of poly(hydroxyether of phenolphthalein) (PHP) with poly(ether sulphone) (PES) were prepared by casting from a common solvent; they were found to be miscible and show a single, composition-dependent glass transition temperature. All the PHP/PES blends exhibited lower critical solution temperature behaviour, i.e. phase separation occurred at elevated temperatures. A F.T.-i.r. study revealed that a hydrogen-bonding interaction occurs between these polymers but it is weaker than in pure PHP. The observed miscibility is hence proposed to be the result of specific interactions between the polymers.

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Scanning tunneling microscope was used to investigate the in vitro assembly of R-phycoerythrin (R-PE) from the marine red alga Polysiphonia urceolata. The results showed that R-PE molecules assembled together by disc-to-disc while absorbing on HOPG surface, which just looked like the rods in the phycobilisomes. When the water-soluble R-PE was dissolved in 2% ethanol/water spreading solution, they could form monolayer film at the air/water interface. Similar disc-to-disc array of R-PE was constituted in the two-dimensional Langmuir-Blodgett film by the external force. It could be concluded that, apart from the key role of time linker polypeptides, the in vivo assembly of phycobiliproteins into phycobilisomes is also dependent on the endogenous properties of phycobiliprotein themselves.

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R-phycoerythrin (R-PE) is one of important proteins involved in capturing light during photosynthesis in red algae, and it is highly fluorescent, and water-soluble chromophores. In vivo, it can transfer the light energy into photosynthetic center, however, it can deliver the captured light energy captured to the surrounding oxygen in vitro and produce reactive oxygen species such as singlet oxygen, which is toxic to tumor cells. R-PE was added to the culture medium of tumor cells, subsequently with irradiation of 488 nm, Argon laser of 25.6 J/cm(2). The result by MTT assay showed that the survival rate decreased with the increase of R-PE concentration from 1 to 100 mg/L. The result from H-3-TdR incorporation demonstrated that the synthesis of DNA reduced when the concentration of R-PE increased from 0.01 to 0.32 mg/L. Besides, pUC18 DNA showed a conversion from supercoiled into linear conformation. The conclusion comes that R-PE mediated PDT can influence the conformation of DNA, and it may be one of the mechanisms of R-PE mediated photodynamic therapy.

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壳聚糖是一种天然的聚阳离子多糖,可以从甲壳类动物、菌类、昆虫等自然资源中提取得到。壳聚糖具有良好的生物相容性,天然无毒,可生物降解,从而在生物工程、制药、化妆品、纺织品、农业等领域引起了广泛关注。 随着对壳聚糖以及壳聚糖衍生物研究的深入,壳聚糖的抑菌活性由于农业杀菌剂的环境问题和抗药性问题的出现而得到重视。但是,对于壳聚糖抑菌活性的研究大都集中于壳聚糖的分子量和脱乙酰度对其活性的影响,而相应的壳聚糖衍生物很少。本文合成了羧甲基壳聚糖希夫碱,N-取代羧甲基壳聚糖,脲取代羧甲基壳聚糖,壳聚糖季铵盐以及羧甲基壳聚糖季铵盐,并对它们的抑菌活性进行了研究,同时探讨了导入基团与抑菌活性间的构效关系。 羧甲基壳聚糖希夫碱对苹果腐烂病菌、番茄早疫病菌和棉花枯萎病菌的抑制活性研究结果表明2-(2-羟基-5-硝基苯亚胺基)羧甲基壳聚糖和2-(2-羟基-5-氯苯亚胺基)羧甲基壳聚糖的抑菌活性高于壳聚糖、羧甲基壳聚糖和2-(2-羟基苯亚胺基)羧甲基壳聚糖,原因可能是2-羟基-5-硝基苯亚胺基和2-羟基-5-氯苯亚胺基两个活性基团的引入。对番茄早疫病菌和苹果轮纹病菌的抑制效果表明,N-取代羧甲基壳聚糖的抑菌活性低于壳聚糖和羧甲基壳聚糖,脲取代羧甲基壳聚糖的抑菌活性高于羧甲基壳聚糖。 测定了壳聚糖季铵盐对灰葡萄孢以及炭疽病菌的抑制活性,结果表明壳聚糖季铵盐的抑制活性高于壳聚糖。因为壳聚糖分子的正电荷可以和菌体细胞壁的负离子相互结合,从而导致菌体死亡,而壳聚糖季铵盐分子中明显的正电性可以促进这种结合能力,从而更进一步的增强抑菌活性。由于相同的原因,抑菌活性随着正电荷的增强而增强,与此同时,高分子量壳聚糖季铵盐由于其较大的体积而具有比低分子量壳聚糖季铵盐更高的抑菌活性。 为了进一步验证氨基的正电性与抑菌活性的关系,合成了羧甲基壳聚糖季铵盐并对这类衍生物对灰葡萄孢和炭疽病菌的抑制活性进行了测定,结果表明,羧甲基壳聚糖季铵盐的抑菌活性高于羧甲基壳聚糖,且部分羧甲基壳聚糖季铵盐的抑菌活性高于壳聚糖。500μg/mL时,N-(2-羟基-5-硝基苯亚甲基)-N,N-二甲基羧甲基壳聚糖和N-(2-羟基-5-氯苯亚甲基)-N,N-二甲基羧甲基壳聚糖对苹果轮纹病菌的抑制率都达到100%。壳聚糖季铵盐中正电荷在抑菌活性中的作用再一次被证实。

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Polysaccharides from Ulva pertusa were isolated and prepared by extraction in hot water and precipitation by ethanol. The water-soluble polysaccharides were chemically well defined, containing 47.0% total carbohydrate, 23.2% uronic acids, 17.1% sulfate groups, 1.0% N and 29.9% ash. Gas chromatography analysis demonstrated that the neutral sugars were mainly composed of rhamnose, xylose and glucose and smaller amounts of mannose, galactose and arabinose. The FTIR and C-13-NMR spectra indicated that basic repeating units of the polysaccharides were (beta-D-GlcpA-(1->4)-alpha-L-Rhap 3S) and (alpha-L-IdopA-(1->4)-alpha-L-Rhap 3S). Fifty ICR mice were used to study the effect of water-soluble polysaccharides from Ulva pertusa on the level of plasma lipids, with inositol niacinate as positive control. The results indicated that the polysaccharides significantly lowered the contents of plasma total cholesterol, low-density lipoprotein cholesterol, triglyceride and markedly increased the contents of serum high-density lipoprotein cholesterol, compared with the hyperlipidemia control group (p<0.01). Moreover, administration of polysaccharides significantly decreased the atherogenic index. The present results suggest that the polysaccharides from Ulva pertusa have great potential for preventing ischemic cardiovascular and cerebrovascular diseases.

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The chemical species of iodine in seven marine algae Codium fragile, Ulva pertusa, Monostroma nitidum, Gracilaria confervoides, Sargassum Kjellmanianum, Dictyopteris divaricata and Laminaria japonica were studied using neutron activation analysis combined with chemical separation. The contents of total iodine, water-soluble iodine, soluble organic iodine, I- and IO3- were determined. The results indicate that the chemical species and contents of iodine in various algae are remarkably different. The highest iodine content of 734 mg/kg (wet basis) was found in Laminaria japonica, with 99.2% of the total iodine being water soluble. The iodine contents of the other six algae are lower and soluble iodine makes up 16-41% of the total. In the aqueous leachate, iodine is mainly I-, which amounts to 61-93% of total water-soluble iodine; the percentages of organic iodine making up 5.5-37.4%, while the contents of IO3- are the lowest, 1.4-4.5%. This result suggests that the mechanism of iodine enrichment is different for various algae and that its bioavailability varies as well. (C) 1997 Elsevier Science B.V.

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Located in the Paleozoic uplift along the southern margin of Tu-Ha basin in eastern Xinjiang, the newly discovered Hongshan Cu-Au deposit occurs in the superimposed Mesozoic volcanic basin upon the north section of later Paleozoic Dananhu-Tousuquan accretionary arc. Kalatage Cu-Au orebelt is controlled by NWW-trend faults, and includes Hongshan and Meiling Cu-Au deposits. The host rocks of Hongshan ore district are mainly rhyolitic-dacitic ignimbrites, whereas Cu-Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and granitic porphyry. Mineralization styles are dominantly veinlet-disseminated and veinlet, occasionally stockwork. The mineral association is chalcopyrite, pyrite, bornite, chalcocite and sphalerite. The hydrothermal alteration consists of silicfication, sericitization, alunitization, pyrophylitization, illitization, hydromuscovitization, and chloritization. Hongshan Cu-Au deposit, on the edge of the desert, is one of the driest areas in eastrn Tianshan. Moreover, the highest temperature has been up to 60℃, and the average rainfall receives only 34.1mm/y. The light rainfall and rapid evaporation in the vicinity of this deposit have allowed the formation of a great variety of water-soluble sulfates. Oxidization zone of this deposit lies on the upper part of primary sulfide orebodies appearing with a depth of 50-60m, which is dominant in sulfate minerals. 1. Based on the field observation, the volcanic and sub-volcanic rock composition, hydrothermal alteration, ore structure and mineralization characteristics, this paper proposed that the Hongshan Cu-Au deposit belongs to a transitional type from high-sulfide epithermal to porphyry Cu-Au deposit, which corresponds with the typical HS-epithermal deposit such as Zijinshan Au-Cu deposit in Fujian Province, SE-China. 2. The Hongshan copper-gold deposit was controlled by the tectonic, stratum, magma activity and volcanic apparatus, whereas Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and fine grained pyritization in hydrothermal activity, and Cu mineralization is closely related to quartz porphyry and hydrothermal explosive breccia. 3. Oxidation zone of Hongshan Cu-Au deposit lies on the upper part of primary sulfide orebodies deposit. 23 sulfate minerals were identified in this work. The results of samples XRD and chemical analysis were furthermore confirmed through thermal, infrared spectrum and mössbauer spectrum analysis. Among those, nine minerals as Ferricopiapite, Cuprocopiapite, Rhomboclase, Parabutlerite, Krausite, Yavapaiite, Metasideronatrite Kroehnkite and Paracoquimbite were founded in China for the first time. And Paracoquimbite was secondly reported in the world (first case reported at 1938 in Chile). 4. EPMA analysis shows that Al impurity in crystal lattice is important to polytype formation of paracoquimbite and coquimbite besides stack fault. 5. Compared with Meiling Cu-Au deposit in the same Kalatage ore belt from the characteristics of δ34S of barite, lithofacies, hydrothermal alteration and homogeneous temperature, Hongshan Cu-Au deposit belongs to the same metallogenic system of HS-epithermal type as Meiling Cu-Au deposit. But Hongshan Cu-Au deposit has less extensive alteration and shallower denudation. 6. Sulfur isotope analyses show that δ34S values of pyrites vary in the range of +1.86‰~+5.69‰, with an average of 3.70‰, mostly in the range of +1.86‰~+3.20‰, and δ34Scp<δ34Spy. Therefore ore-forming fluid of porphyry comes from mantle and was contaminated by the earth’s crust. Sulfur isotope has reached balance in ore-forming process. 7. Sulfur isotope analyses show that δ34S values of sulfates vary in the range of +2.15‰~+6.73‰, with an average of +3.74‰, mostly equals as δ34S values of primary sulfides in Hongshan Cu-Au deposit. So supergene sulfates inherit sulfur of primary sulfide. δ34S values are mostly same in different sulfates. As well as pyrite and chalcopyrite, volcanic hot spring and associated native sulfur underground also provide water medium and sulfur during the formation process of sulfate. 8. According to the EPMA of sample chalcopyrite and pyrite in Hongshan Cu-Au, the value of Cu/Ni is 0.98-34.72, mostly close to the value of 5, which shows that Hongshan deposit is a typical volcanogenic magmaic hypothermal deposit. Au and Ag, Zn, Te and Bi are positive correlation, Cu and Hg, Se, Sb are positive correlation, indicates Au and Cu don’t locate in the factor of mineralization of same mineralization groups. The reasons of gold concentration in the oxidation zone are: 1). Change of redox potential (Eh) makes gold to deposit from the liquid of mineralization zone; 2). PH is one of the most factors of gold’s deposition; 3). Soluble complex and colloid of gold can be adsorbed easily. 9. The biotite and hornblende K-Ar isotopic ages from the wall rock-quartz diorite, biotite granite and monzonite granite are 231.99±3.45Ma, 237.97±2.36Ma and 296.53±6.69Ma respectively. The ore-bearing rhyolitic breccia lava contains breccia of the biotite granite which indicates the volcanism and related Cu-Au mineralization occurred later than the granite, possibly in Mesozoic. K-Ar ages of granitoids in Sanya, Baishiquan and Hongliugou area and Molybdenite Re-Os age of Baishan Mo deposit all are in Triassic. Besides late Paleozoic magmatism, igneous magmatic event of Mesozoic was widespread in eastern Tianshan. 10. The K-Ar age dating indicates that the K-Ar age of Voltaite occurred below surface 1m is 56.02±3.98Ma, K-Ar age of Ferricopiapite occurred below surface 1.5m is 8.62±1.12Ma, K-Ar age of Yavapaiite occurred below surface 14 m is 4.07±0.39Ma, and K-Ar age of Voltaite occurred below surface 10 m is 14.73±1.73Ma. So the age interval of oxidation zone of Hongshan copper-golden bed is between 60 -3.38Ma. Oxidization occurred at Caenozoic era (from 65Ma), which can be identified through comparing with different deposits oxidation zone in other countries. The coupling between global tectonic event and climatic change event which occur from Caenozoic era has some effect on epigeosphere system, which can act on the surface of bed oxidation zone similarly. It induces that the age mentioned above coincide with collision of India-Asia and multistage uplifting of Qinhai-Tibet Plateau happened subsequently. Bed oxidation zone is the effect and record of collision and uplifting of Tibet Plateau. The strong chemical weathering of surface accumulation to which was leaded by PETM event occurred Paleocene and Eocene is the reason of Voltaite sharply rises. On the contrary, Ferricopiapite formed due to the global cold weather. The predecessor did much research through biota, isotopes, susceptibility, but this paper try to use different sulfate mineral instead of climatic change. So the research of sulfate minerals not only indicates a great deal of oxidized zone feature, but also the intergrowth of sulfate minerals may be used to trace paleoenviroment and paleoclimate of oxidation zone. 11. Analysis of the information of alteration and mineralization features of four bore cores, induced activity polarization well logging and Eh-4 geophysical section, deep mineralization anomaly objects of Hongshan ore districts shows low resistance, middle and high polarization, measurements of Eh-4 consecutive conductance section show the existing of concealed porphyry ore body deeper than 450m, on the top of and around rock body there are low resistance body ranged from 100-300Ω•m, this area may be the ore-bearing part. In a word, Hongshan Cu-Au deposit deposit is a combine of upper HS-style epithermal Au deposit and deeper porphyry mineralization system. It has great potential to find large HS-style epithermal-porphyry Au-Cu deposits. This paper consists of seven chapters and twenty seven sections. The geological character of deposit is basic condition in this work. Constitute of oxidation zone, research of sulfate mineral, relation between oxidation and primary zone, K-Ar ages of potassic sulfate are key parts of thesis. Genesis of ore deposit is the further expansion of this research. Analysis of ore-controlling factors is the penetration above basic. Analysis of potential is application of exploration.

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It is well known that our country is short of water-soluble potassium, but rich in insoluble potassium ores. Based on the work of the formers, using the orthogonal and monofactor experiments, the author optimized the production technology of micro-porous potassium silicon calcium mineral fertilizer by non-stirring hydrothermal chemical reaction when the alkaline earth booster CaO was available. The influences of temperature、time、reactant ratio and water-solid ratio on the dissolution rate of production’s elements were studied by orthogonal experiments, and the production technology was further optimized by monofactor experiments. By XRD、SEM、EDS and dissolving experiments, it was systematically studied that the effects of the reactant ratio、reaction time and reaction temperature on the properties of the production obtained by the hydrothermal reaction between KAlSi3O8 and CaO. The results showed that:when changing of the reaction condition, the reaction productions included tobermorite、 hibschite、α-C2SH and K2Ca(CO3)2; among which, K2Ca(CO3)2 was not the first production containing potassium, but K2Ca(CO3)2 was synthesized by the reaction among KOH、Ca(OH)2 and CO2. Whether the phase was synthesized was related to not only the reaction condition, but also their physicochemical properties; when the reaction condition was changed, the changes of different phases were different. The results of XRD and dissolution rate experiments explained the dissolution characteristic of every element of hydrothermal productions very well, and the relation between the dissolution rate of element and the phase of productions poured a good illumination on the production technology. The results of SEM and EDS showed that: hydrogarnet looked like spherical, and its surface was covered by some productions including K phase and Ca、Si phase; but the morphology of tobermorite was platy or lamellar or needlelike, and parts of Si in the structure of tobermorite were substituted by Al,and some K+ cations were inserted into the Ca interlayer of tobermorite at the same time. It was the first time that the interface between KAlSi3O8 and Ca(OH)2 was observed directly by SEM and EDS after the hydrothermal reaction, and the mechanism of hydrothermal reaction of KAlSi3O8 and Ca(OH)2 was further discussed. These results indicated that: the Ca-KAlSi3O8 intermediate compound was formed at first, and some K was released into the solution and KOH was produced at the same time; the C-S-H phase appeared before hydrogarnet, and then hydrogarnet was synthesized when the chemical reaction was carried on; if the reaction was carried on furthermore, α-C2SH、tobermorite and other C-S-H phases of different atom ratio appeared. The author found that the structure of KAlSi3O8 would be more drastically destroyed if there were some reactants, such as Ca(OH)2 which reacted with KAlSi3O8 and new phases were formed after the hydrothermal reaction between KAlSi3O8 and alkaline solution of equal ionic strength was finished. With the combination of calcination and hydrothermal reaction methods, the dissolution rate of products were greatly improved when the hydrothermal reaction was carried out after KAlSi3O8 and CaCO3 were calcined. Furthermore, the author has tentatively explored how to evaluate the effects of the differences of the activity of lime on the dissolution properties of hydrothermal products.

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The Grove Mountains, including 64 nunataks, is situated on an area about 3200km2 in the inland ice cap of east Antarctica in Princess Elizabeth land (72o20'-73°101S, 73°50'-75o40'E), between Zhongshan station and Dome A, about 450km away from Zhongshan station (69°22'S, 76°22'E). Many workers thought there was no pedogenesis in the areas because of the less precipitation and extreme lower temperature. However, during the austral summer in 1999-2000, the Chinaer 16 Antarctic expedition teams entered the inland East Antarctica and found three soil spots in the Southern Mount Harding, Grove Mountains, East Antarctica. It is the first case that soils are discovered in the inland in East Antarctica. Interestingly, the soils in this area show clay fraction migration, which is different from other cold desert soils. In addition, several moraine banks are discovered around the Mount Harding. The soil properties are discussed as below. Desert pavement commonly occurs on the three soil site surfaces, which is composed of pebbles and fragments formed slowly in typical desert zone. Many pebbles are subround and variegated. These pebbles are formed by abrasion caused by not only wind and wind selective transportation, but also salt weathering and thaw-freezing action on rocks. The wind blows the boulders and bedrocks with snow grains and small sands. This results in rock disintegration, paved on the soil surface, forming desert pavement, which protects the underground soil from wind-blow. The desert pavement is the typical feature in ice free zone in Antarctica. There developed desert varnish and ventifacts in this area. Rubification is a dominant process in cold desert Antarctic soils. In cold desert soils, rubification results in relatively high concentrations of Fed in soil profile. Stained depth increases progressively with time. The content of Fed is increasing up to surface in each profile. The reddish thin film is observed around the margin of mafic minerals such as biotite, hornblende, and magnetite in parent materials with the microscope analyzing on some soil profiles. So the Fed originates from the weathering of mafic minerals in soils. Accumulations of water-soluble salts, either as discrete horizons or dispersed within the soil, occur in the soil profiles, and the salt encrustations accumulate just beneath surface stones in this area. The results of X-ray diffraction analyses show that the crystalline salts consist of pentahydrite (MgSO4-5H2O), hexahydrite (MgSO4-6H2O), hurlbutite (CaBe2(PO4)2), bloedite (Na2Mg(S04)2-4H2O), et al., being mainly sulfate. The dominant cations in 1:5 soil-water extracts are Mg2+ and Na+, as well as Ca2+ and K+, while the dominant anion is SO42-, then NO3-, Cl- and HCO3-. There are white and yellowish sponge materials covered the stone underside surface, of which the main compounds are quartz (SiO2, 40.75%), rozenite (FeSOKkO, 37.39%), guyanaite (Cr2O3-1.5H2O, 9.30%), and starkeyite (MgSO4-4H2O, 12.56%). 4) The distribution of the clay fraction is related to the maximum content of moisture and salts. Clay fraction migration occurs in the soils, which is different from that of other cold desert soils. X-ray diffraction analyses show that the main clay minerals are illite, smectite, then illite-smectite, little kaolinite and veirniculite. Mica was changed to illite, even to vermiculite by hydration. Illite formed in the initial stage of weathering. The appearance of smectite suggests that it enriched in magnesium, but no strong eluviation, which belongs to cold and arid acid environment. 5) Three soil sites have different moisture. The effect moisture is in the form of little ice in site 1. There is no ice in site 2, and ice-cement horizon is 12 cm below the soil surface in site 3. Salt horizon is 5-10 cm up to the surface in Site 1 and Site 2, while about 26cm in site 3. The differentiation of the active layer and the permafrost are not distinct because of arid climate. The depth of active layer is about 10 cm in this area. Soils and Environment: On the basis of the characteristics of surface rocks, soil colors, horizon differentiation, salt in soils and soil depth, the soils age of the Grove Mountains is 0.5-3.5Ma. No remnants of glaciations are found on the soil sites of Mount Harding, which suggests that the Antarctic glaciations have not reached the soil sites since at least 0.5Ma, and the ice cap was not much higher than present, even during the Last Glacial Maximum. The average altitude of the contact line of level of blue ice and outcrop is 2050m, and the altitude of soil area is 2160m. The relative height deviation is about 110m, so the soils have developed and preserved until today. The parental material of the soils originated from alluvial sedimentary of baserocks nearby. Sporepollen were extracted from the soils, arbor pollen grains are dominant by Pinus and Betula, as well as a small amount Quercus, Juglans, Tilia and Artemisia etc. Judging from the shape and colour, the sporepollen group is likely attributed to Neogene or Pliocene in age. This indicates that there had been a warm period during the Neogene in the Grove Mountains, East Antarctica.

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Snow chemistry research helps to found the basis of studying ice cores. Samples of fresh snow and snow pits were collected from East Rongbuk Glacier on the north slope of Mt. Qomolangma during October, 2002. Major soluble ions (Na~+, NH_4~+, K~+, Mg~(2+), Ca~(2+), Cl~-, NO_3~- and SO_4~(2-)) andδ~(18)O were detected for analysis. Source analysis showed that major sources contributing to the snow chemistry in Mt. Qomolangma region are remote Asian dust and salt lake dust, sea-salt aerosols from Indian monsoon, local rock-mineral dust, human activities and natural atmospheric procedures. Principal factor analysis indicated that high-concentration group was dominated by continental dust with little oceanic source, indicating continental or local precipitation, while the low group dominated by oceanic aerosols indicated oceanic precipitation. Local mineral dust was a minor a source characterized mainly by Ca~(2+), Mg~(2+) contribution. Ammonia related mainly with continental dusts and nitrogen-circulation processes in the atmosphere, it also had a peculiar source should be seasonal agriculture activities in the south Asia. Nitrate showed bad correlations with other ions for its special chemical characteristics. δ~(18)O and major soluble ions displayed obvious seasonal variations. The summer precipitation had very low ion loadings and relatively lower heavy oxygen isotope from the Indian Ocean with occasionally ion peaks formed by local evaporation. While the winter and spring precipitation had high ion loadings and δ~(18)O value for the great amount of continental dust and evaporated vapors. Frequent fluctuations of δ~(18)O and ion concentration occur during the transitional period, indicating alternated precipitations by various air mass types. Ion concentration in snow from the Qomolangma region is comparable with from the Antactica, representing relatively pure background of atmospheric environment on earth. While the high concentration is close to the glaciers' located near the major sources of Asian dust. Compared with the snow chemistry of South Slope of Mt. Qomolangma, the North Slope has lower sea-salt ion concentration during summer monsoon and higher concentration of all major ions during pre- and post-monsoon period due to it's special geophysical location.

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Three soil spots were found in Grove Mountains, east Antarctica during 1999-2000, when the Chinare 16th Antarctic expedition teams entered the inland Antarctica. The characteristics of soils in Grove Mountains are desert pavement coating the surface, abundant water soluble salt, negligible organ matter, and severe rubification and salinization, scarces of liquid water, partly with dry permafrost, corresponding with the soils of McMurdo, Transantarctic. The soils age of Grove Mountains is 0.5-3.5Ma. Podzolization and redoximorphism are the main features in coastal Wilks region, in addition, there is strong enrichment of organic matter in many soils of this region. The main soil processes of Fildes Peninsula of King George Island include the intense physical weathering, decalcification and weakly biochemical processes. Peat accumulation is the main processes in Arctic because of humid and cold environment.Based on synthesis of heavy minerals, particle size, quartz grain surface textures, as well as pollen in soils, the soils parent materials of Grove Mountains derived from alluvial sediment of the weathering bedrocks around soils, and formed during the warm period of Pliocene. The detailed information is followed .l)The results of heavy minerals particle size showed the parent minerals derived form the weathering bedrocks around soils. 2)The quartz sand surface textures include glacial crushing and abrasion such as abrasive conchoidal fractures and grain edges, abrasive subparallel linear fractures and angularity, subaqueous environments produce V-shaped and irregular impact pits, polished surface, and chemical textures, such as beehive solution pits, which showed the water is the main force during the sediment of the soil parent minerals. 3)The pollen consist of 40 plant species, of which at least 5 species including Ranunculaceae, Chenopodiaceae, Artemisia, Gramineae, Podocarpus belong to the Neogene vegetation except the species from the old continent. Compared with Neogene vegetation of Transantarctic Mountains, Antarctic, we concluded that they grow in warm Pliocene.

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The first Eu3+ chelate-based phosphorescence probe specific for singlet oxygen has been designed, synthesized and characterized. The probe is highly sensitive, selective and water soluble for time-resolved luminescence detection of singlet oxygen with a detection limit of 2.8 nM.

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Here we used cytokinesis-block micronucleus assay to measure the biological response along the penetrate depth of ions in water in human lymphocytes exposed to 100 MeV/u incident carbon ions in vitro. Polyethylene shielding was used to change the penetration depth of ions in water. A quantitative biological response curve was generated for micronuclei induction. The results showed a marked increase with the penetrate depth of ions in water in the micronuclei formation, which was consistent with a linearenergy- transfer dependent increase in biological effectiveness. The dose–response relationship for MN information was different at different penetrate depth of ions in water, at the 6 and 11.2 mm penetrate depth of ions in water, the dose–response relationships for the micronucleus frequencies induced by carbon ions irradiation were linear; while it was power function at 17.1 mm penetrate depth.

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A new hydrogen-bonded dinuclear copper(II) coordination compound has been synthesized from the Schiff-base ligand 6-(pyridine-2-ylhydrazonomethyl)phenol (Hphp). The molecular structure of [Cu-2(php)(2)(H2O2)(2)(ClO4)](ClO4)- (H2O) (1), determined by single-crystal X-ray diffraction, reveals the presence of two copper(II) centers held together by means of two strong hydrogen bonds, with O center dot O contacts of only 2.60-2.68 angstrom. Temperature-dependent magnetic susceptibility measurements down to 3 K show that the two metal ions are antiferromagnetically coupled (J = -19.8(2) cm(-1)). This exchange is most likely through two hydrogen-bonding pathways, where a coordinated water on the first Cu, donates a H bond to the O atoms of the coordinated php at the other Cu. This strong O center dot H (water) bonding interaction has been clearly evidenced by theoretical calculations. In the relatively few related cases from the literature, this exchange path, mediated by a (neutral) coordinated water molecule, was not recognized.

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In this paper, a calix[4]arene derivative, 5,11,17,23-butyl-25,26,27,28-tetra-(ethanoxycarbonyl)-methoxy-calix[4]arene (L), is investigated as a host to recognize alkali metal ions (Li+, Na+, K+, Rb+ and Cs+) at the interface between two immiscible electrolyte solutions (ITIES). Well-defined cyclic voltammograms are obtained at the micro- and nano-water \ 1,2-dichloroethane (W \ DCE) interfaces supported at micro- and nano-pipets.