61 resultados para Nichiren, 1222-1282.


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A series of solid electrolytes Ce1-xGdxO2-x/2(x=0 similar to0.6) was prepared by sol-gel method. The structure, thermal expansion coefficient and electrical properties of the solid solutions were systematically studied. XRD data showed that a complete cubic fluorite structure was formed at 160 degreesC. The purity of the product prepared by the sol-gel method is higher, the grain size is uniformly smaller. They were easily sintered into highly dense ceramic pellets at 1 300 degreesC. The sintering temperature was significantly lower than that by traditionally high temperature solid phase reaction method. The thermal expansion coefficient of Ce0.8Gd0.2O1.9, determined from high- temperature XRD data, is 8. 125 X 10(-6) K-1. Impedance spectra analyses showed that the grain-boundary resistance of the solid electrolyte prepared by sol-gel method was reduced or even eliminated. The conductivity of Ce0.8Gd0.2O1.9 is 5.26 X 10(-3) S/cm at 600 degreesC. The activation energy (E-a) is 0.82 eV.

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Electroactive self-assembled monolayers (SAMs) with well-defined electrochemical responses were prepared by spontaneous assembly of the inclusion complexes (CD/C8VComegaSH) of viologen-attached alkanethiols (C8VComegaSH) and alpha- and beta-cyclodextrin (CD). They were characterized by X-ray photoelectron spectroscopy and cyclic voltammetry. The results demonstrate that the chemisorption process of CD/C8VComegaSH on gold substrate occurs through S-Au bonds, and that the redox sites in SAMs of CD/C8VComegaSH are in a much more uniform environment than those in SAMs of C8VComegaSH.

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Gas phase ion-molecular reactions of C-60 with the ion system of CS2 have been studied in the ion source of mass spectrometer. It was found for the first time that the sulfuric derivative of C-60-C60S+ was the main ions in the ion source, they did not react with C-60 to form adduct ions due to their highly saturated structures. According to the dynamic analysis, the product ion came from the reaction of C-60 with the fragment ion S+. The adduct ion may have the structure of epsulfide that is advantageous in energy.

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C_(60)硫衍生物──C_(60)S~+的气相合成刘子阳,郝国仑,郭兴华,刘淑莹(中国科学院长春应用化学研究所,长春,130022)关键词C_(60),CS_2,离子-分子反应自实现C(60)的宏观量合成以来[1],通过将C(60)进行化学衍生进而改变?..

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Four new (1-4) and seven known (5-11) benzaldehyde derivatives were characterized from the liquid fermentation cultures of Eurotium rubrum, an endophytic fungus that was isolated from the inner tissue of stems of the mangrove plant Hibiscus tiliaceus. The structures of these compounds were determined by extensive analysis of their spectroscopic data. Among these metabolites, compound 1, which was named as eurotirumin, possesses a new carbon skeleton with a cyclopentabenzopyran ring system.

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C-type lectins are a superfamily of Ca2+ dependent carbohydrate-recognition proteins which play significant diverse roles in nonself-recognition and clearance of invaders. In the present study, a C-type lectin (CfLec-2) from Zhikong scallop Chlamys farreri was selected to investigate its functions in innate immunity. The mRNA expression of CfLec-2 in hemocytes was significantly up-regulated (P < 0.01) after scallops were stimulated by LPS. PGN or beta-glucan, and reached the highest expression level at 12h post-stimulation, which was 72.5-, 23.6- or 43.8-fold compared with blank group, respectively. The recombinant Cflec-2 (designated as rCfLec-2) could bind LPS, PGN, mannan and zymosan in vitro, but it could not bind beta-glucan. Immunofluorescence assay with polyclonal antibody specific for Cflec-2 revealed that CfLec-2 was mainly located in the mantle, kidney and gonad. Furthermore, rCfLec-2 could bind to the surface of scallop hemocytes, and then initiated cellular adhesion and recruited hemocytes to enhance their encapsulation in vitro, and this process could be specifically blocked by anti-rCfLec-2 serum. These results collectively suggested that CfLec-2 from the primitive deuterostome C. farreri could perform two distinct immune functions, pathogen recognition and cellular adhesion synchronously, while these functions were performed by collectins and selectins in vertebrates, respectively. The synchronous functions of pathogen recognition and cellular adhesion performed by CfLec-2 tempted us to suspect that CfLec-2 was an ancient form of C-type lectin, and apparently the differentiation of these two functions mediated by C-type lectins occurred after mollusk in phylogeny. (C) 2010 Elsevier Ltd. All rights reserved.

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An effective nonlinear alternative-current (AC) response to granular nonlinear-composite with spherical inclusions embedded in a host medium under the action of an external AC field is investigated by using a perturbation approach. The local potentials of composite at higher harmonics are derived both in a region of local inclusion particles and in a local host region under the action of a sinusoidal field E-1 sin ω t + E-3 sin 3ω t. An effective nonlinear-response to composite and the relationship between the effective nonlinear-responses at the fundamental frequency and the third harmonics are also studied for the spherical inclusions in a dilute limit.

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大洋环流是海盆尺度上海水的持久流动,是海洋中质量、热量输运的主要通道,对全球气候变化有重要影响。经过二十年来的大量调查研究,对海洋上层的风生大洋环流有了比较充分的认识。然而,近几十年来的大量观测显示,大洋环流的垂直结构并非像传统认识的那样单一,在很多区域存在与之反向的次表层潜流,如北赤道流(NEC)下方的北赤道逆流(NEUC)、棉兰老海流(MC)下方的棉兰老潜流(MUC),吕宋岛附近黑潮(KC)下方的吕宋潜流(LUC),东澳大利亚海流(EAC)下方的大堡礁潜流(GBRUC)和东澳大利亚潜流(EAUC),阿加勒斯海流(AC)下方的阿加勒斯潜流(AUC)等。这些潜流一般分布在西边界,或者在西边界处增强,称为“西边界潜流(WBUC)”。与表层环流相比,对次表层潜流的结构和形成机制认识不足,因此利用不断更新的各种实测数据和高分辨率同化数据,通过理论分析和数值试验,探讨研究次表层潜流的分布特征和形成机制,对于大洋环流动力学理论的进一步发展具有重要的科学意义。 本文利用中国ARGO资料中心提供的ARGO资料、全球简单海洋资料同化分析系统产生的SODA同化资料和日本地球模拟器模拟出来的OFES资料,分析了北太平洋潜流(NEUC、MUC和LUC)、南太平洋潜流(GBRUC和EAUC)和南印度洋潜流(AUC)的时间和空间分布特征,并基于温跃层以下转向的地转判据分析了其形成机制。主要结果如下: (1)在菲律宾以东海域,表层的NEC在12N附近的西边界分叉,形成向北的KC和向南的MC。在400-800米左右棉兰老岛东侧128E-130E处出现与上层海流方向相反的潜流MUC,MUC在9N和12N附近转向东并分成2支,汇入NEC下方的2支并行向东流的NEUC。到了1000米左右,吕宋岛东侧122E-124E处出现LUC,而MUC也有向岸的趋势,限制在127E以西的范围,两者在12N附近相遇,然后转向东汇入NEUC。随着深度的加深,NEUC的北侧分支流轴向北偏移。从SODA资料和OFES资料在8N、18N和138E断面的气候态年平均和月平均温度剖面可以很清晰的看出,温跃层分别呈现东高西低、西高东低和南高北低的趋势,这与各个断面上表层流和次表层逆流之间等值线倾斜方向一致。从月平均的速度剖面可以看出,MC一般位于600db以上,600db以下出现北向次表层潜流MUC,MUC春夏较强,秋冬较弱;KC一般位于500db以上,个别月份深入到2000db,其下方均有南向的LUC出现,LUC春夏较弱,秋冬较强;上层西向NEC的主体一般位于400db以上,其下方均有东向的NEUC出现,NEUC春夏较强,秋冬较弱。 在北太平洋菲律宾以东海域,同时满足两个判据的区域与潜流的发生区域符合情况较好,唯一的不同在于LUC汇入NEUC的区域没有同时满足两个判据。这是由于在吕宋岛和棉兰老岛东侧,海底地形较为陡峭,海流情况较为清晰,沿岸涡较少,而且在此区域内温跃层较浅,这些都为形成温跃层以下的地转流反向提供了充分的条件。 (2)在澳大利亚以东海域,表层的南赤道流(SEC)在澳大利亚东岸15S附近分叉,分为向北的北昆士兰海流(NQC)和向南的东澳大利亚海流(EAC)。500m-1000m,23S附近出现一支北向的次表层海流,沿着澳大利亚陆坡经过大堡礁抵达巴布亚新几内亚沿岸转向东,汇入新几内亚沿岸潜流(NGCUC),这支海流就是大堡礁潜流(GBRUC)。1000m-2000m,SEC下方15S附近出现东向的逆流。在2000m以下,由于地形的影响,海流局限在几个不连续的部分,而且流型较乱。从SODA资料和OFES资料在18S和30S断面的气候态年平均和月平均温度剖面可以很清晰的看出,温跃层均呈现西高东低的趋势。在18S,南向的EAC一般位于400db以上,其下方均有持续的GBRUC出现,一般有两个中心,春夏季较强,秋冬季较弱。在30S断面,EAC一般存在于2000db以上,其下方的次表层流并不规则。从此海域的气候态月平均分布来看,在大多月份没有北向的逆流存在,这说明其下方的次表层逆流并不是一个常年存在的现象。 在南太平洋,同时满足两个判据的区域包括SEC下方逆流的发生区域和澳大利亚东岸的沿岸区域,这些区域部分与潜流的发生区域符合较好,只是在30S左右并没有发生潜流的区域也同时满足判据。这是由于在30S附近,温跃层较深,导致了地转流较深,同时此区域内海底地形变化比较大,虽然在此位置形成了逆向的地转流,但是因为地形的限制,在此区域内不能形成有体系的逆流。 (3)在西南印度洋,SEC在非洲东岸分叉,形成一支源于25S的西南向海流——AC,这支海流平均流速达90cm/s左右,最大速度超过140cm/s。在其下方2000m左右,从35S开始在岸边出现东北向逆流——AUC,速度较小,仅为2cm/s左右。从31S、33S和35S断面的气候态年平均温度断面可以很清晰的看出,温跃层明显呈现西高东低的趋势。从月平均经向流速断面可以看出,在各个月份AC下方均出现不同强度的AUC,AC和AUC之间的等值线倾斜方向与温跃层的倾斜方向一致。 在南印度洋,满足判据的区域包括南非沿岸AUC的发生区域和南非东南的部分海域,南非沿岸的AUC紧靠岸边且深度较深,这是因为此区域内温跃层较深,导致形成的地转流位置较深,而形成的逆流由于与海底的摩擦而大大削弱。南非东南部分海域满足判据,大概是由于此区域海流比较复杂,而且此海域多涡。 表面风应力的强迫以及风生环流的斜压调整,使得潜流所在海域的海平面高度和温跃层倾斜方向相反,热带流涡和副热带流涡西向强化加强了该海域温跃层的倾斜程度,从而导致了次表层地转流反向。因此,大洋中次表层潜流是大洋斜压风生环流不可缺少的重要部分。但是在不同的海域存在不同的地形分布和海流分布,所以此理论只在某些合适的区域得到很好的体现。

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本文构建了长江口外海域三维悬浮泥沙输运数值模型,其中水动力模型中主要考虑了潮汐潮流、出入径流及风浪等作用,输运模型中考虑了粘性泥沙的絮凝、粘性和非粘性泥沙的再悬浮等过程。并与2006年8月份在长江口外海域获得的定点连续站测流资料及悬浮泥沙的观测资料进行了比较。为了进一步提高模式结果的精确性,采用将动力模式与实测资料相结合的趋近同化方法,在连续方程和泥沙输运方程中分别增加一个松弛项,将模拟结果向已有实测调和常数的控制点推算潮高值和悬沙浓度观测值趋近。数值实验证明,将验潮站资料和泥沙观测资料引入到数值模式中去,可以有效的改善模式的模拟结果。将该方法运用到长江口外附近海域的悬浮泥沙数值模拟当中,并泥沙输运水平紊动扩散系数也做了合理的修改,其模拟结果也得到了不错的改进,所得结果适用于计算长江口外海域的水动力和泥沙输运情况。 可以大体得到泥沙在长江口内外分布规律:悬浮泥沙浓度自近岸向外海降低,长江口外123°E以东浓度一般不超过10mg/l,终年悬浮泥沙高值区见于河口区,一般超过300mg/l,以长江口、杭州湾悬浮泥沙浓度最高。悬浮泥沙浓度垂向剖面的计算值与观测数据符合良好。 在潮周期中,悬浮泥沙浓度的变化与

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We used an eddy covariance technique to measure evapotranspiration and carbon flux over two very different growing seasons for a typical steppe on the Inner Mongolia Plateau, China. The rainfall during the 2004 growing season (344.7 mm) was close to the annual average (350.43 mm). In contrast, precipitation during the 2005 growing season was significantly lower than average (only 126 mm). The wet 2004 growing season had a higher peak evapotranspiration (4 mm day(-1)) than did the dry 2005 growing season (3.3 mm day(-1)). In 2004, latent heat flux was mainly a consumption resource for net radiation, accounting for similar to 46% of net radiation. However, sensible heat flux dominated the energy budget over the whole growing season in 2005, accounting for 60% of net radiation. The evaporative rate (LE/R-n) dropped by a factor of four from the non-soil stress to soil water limiting conditions. Maximum half-hourly CO2 uptake was -0.68 mg m(-2) s(-1) and maximum ecosystem exchange was 4.3 g CO2 m(-2) day(-1) in 2004. The 2005 drought growing stage had a maximum CO2 exchange value of only -0.22 mg m(-2) s(-1) and a continuous positive integrated-daily CO2 flux over the entire growing season, i.e. the ecosystem became a net carbon source. Soil respiration was temperature dependent when the soil was under non-limiting soil moisture conditions, but this response declined with soil water stress. Water availability and a high vapor pressure deficit severely limited carbon fixing of this ecosystem; thus, during the growing season, the capacity to fix CO2 was closely related to both timing and frequency of rainfall events. (c) 2007 Published by Elsevier Masson SAS.

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A sensitive method for the determination of long-chain fatty acids (LCFAs) (>C20) using 1-[2-(p-toluenesulfonate)-ethyl]-2-phenylimidazole-[4.5-f]-9,10-phenanthrene (TSPP) as tagging reagent with fluorescence detection and identification with post-column APCI/MS has been developed. The LCFAs in bryophyte plant samples were obtained based on distillation extraction with 1: 1 (v/v) chloroform/methanol as extracting solvent. TSPP could easily and quickly label LCFAs at 90 degrees C in the presence of K2CO3 catalyst in DMF. Eleven free LCFAs from the extracts of bryophyte plants were sensitively determined. Maximal labeling yields close to 100% were observed with a five-fold excess of molar reagent. Separation of the derivatized fatty acids exhibited a good baseline resolution in combination with a gradient elution on a reversed-phase Eclipse XDB-C-8 column. Calculated detection limits from 1.0 pmol injection, at a signal-to-noise ratio of 3, were 26.19-76.67 fmol. Excellent linear responses were observed with coefficients of >0.9996. Good compositional data were obtained from the analysis of the extracted LCFAs containing as little as 0.2 g of bryophyte plant samples. Therefore, the facile TSPP derivatization coupled with HPLC/APCI/MS analysis allowed the development of a highly sensitive method for the quantitation of trace levels of LCFAs from biological and natural environmental samples. (c) 2006 Elsevier B.V. All rights reserved.

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Hydrocarbon migration and accumulation are the important process to form reservoirs in sedimentary basins, and their researches are usually very difficult to be done in petroleum geology. In this paper, the west segment of northern margin of the Qaidam Basin was selected as study area. The concept of fault open coefficient, that combines multi-factors dealing with fault sealing, was applied to estimate semi-quantitatively the sealing characteristics of six faults which were considered controlling the hydrocarbon migration and accumulation. The data from boreholes were investigated to appraise the permeable characteristics of lithology combinations upon and beneath the unconformity surface. The result suggests that the basal conglomerates consist frequently the carriers. The data from boreholes and outcrops were collected to describe the sand carrier system. In order to eliminate the influence of inverse activities of the basin that made the formations be very steep, author adopts the phase method to build the basin models: for the steps before Pliocene the recovered true thickness maps were used to build the basin block; for the steps after Pliocene, the structure maps of today were used to build the basin block. During the modeling process, the results were calibrated by various measured data . the modeled results includes the dynamic evolvement course of trap form phase, vitrinite reflectance mature, the source rock expelled hydrocarbon intensity and fluid potential and petroleum plays. Author integrates the source rock expelled hydrocarbon intensity, fluid potential and carrier system and apply the migration technology based on percolation theory to simulate the oil and gas migration and accumulation course in the main accumulation times. The dominant pathways of oil and gas may show clearly the prospect distribution. Based on the hydrocarbon migration characteristics, the main control factors were synthesized, that including the effective source rock distribution, the match relationship of structural trap forming and hydrocarbon expelling from source rocks, the unconformity of Mesozoic and Cenozoic, the structures and the faults movement at Quaternary Finally, the author figures out the prospect plays in the study area.

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Groundwater basin is important for water supply in northern China. The paper took the Jingsheng Basin in Lingshi County, Shanxi Province as a case to study the basin groundwater system by numerical modeling. The hydrogeological characteristics were analysed basing on the field investigation, and a three-dimensional groundwater flow model was established to describe the groundwater flow system in the Jingsheng groundwater basin. The boundary of the model was determined by using geophysics and GIS data, and the lumped parameter model of runoff was used to depict the transform between the surface water and groundwater, and the groundwater dating data was used to calibrate the model. All these methods were used to improve the model. The Software Visual MODFLOW 2000 was applied to set up the numerical groundwater flow model. The groundwater flow pattern in the average year, the high-water year and the low-water year were simulated respectively by the model. Some new cognition to the groundwater movement in Jingsheng Basin was obtained in the paper. The difficult problems were resolved when using the conventional and theoretical analysis to forecast and appraise the exploitation of the groundwater, and supplies the instructional technology base for the reasonable exploitation and optimization collocation. The numerical model will improve evaluation of the basin groundwater resources.