959 resultados para 1.5 GPA
Resumo:
1,5-二氮杂戊二烯盐(vinamidium salts)与4-硝基苯甲脒盐在碱性物质的存在下发生成环反应得含嘧啶环的硝基化合物;硝基化合物用Pd/C和水合肼还原得到棒状含氮芳杂环二胺——2,5-二(4-氨基苯基)嘧啶.通过1H-NMR,13C-NMR,IR,MS及元素分析确证了含氮芳杂环二胺及其中间产物的结构.这种二胺或加一定量对苯二胺与均苯二酐(PMDA)或联苯二酐(BPDA)通过两步法聚合获得一系列聚酰亚胺,通过红外、动态力学、静态力学、热重分析、广角X射线衍射等实验测试了该类聚合物的结构、热性能、机械性能及结晶性能.
Reaction and formation of crystalline silicon oxynitride in Si-O-N systems under solid high pressure
Resumo:
Oxidized amorphous Si3N4 and SiO2 powders were pressed alone or as a mixture under high pressure (1.0-5.0 GPa) at high temperatures (800-1700 degreesC). Formation of crystalline silicon oxynitride (Si(2ON)2) was observed from amorphous silicon nitride (Si3N4) powders containing 5.8 wt% oxygen at 1.0 GPa and 1400 degreesC, The Si2ON2 coexisted with beta -Si3N4 with a weight fraction of 40 wt%, suggesting that all oxygen in the powders participated in the reaction to form Si2ON2. Pressing a mixture of amorphous Si3N4 of lower oxygen (1.5 wt%) and SiO2 under 1.0-5.0 GPa between 1000 degrees and 1350 degreesC did not give Si2ON2 phase, but yielded a mixture of alpha,beta -Si3N4, quartz, and coesite (a high-pressure form of SiO2). The formation of Si2ON2, from oxidized amorphous Si3N4 seemed to be assisted by formation of a Si-O-N melt in the system that was enhanced under the high pressure.
Resumo:
采用柠檬酸配合法合成了结构呈层状ABO_3的La_4BaCu_5O_(12)复合氧化物,并以它为基体合成了一系列Mn取代Cu的样品(La_4BaCu_(5-x)Mn_xO_(12),x=1~5。)并利用XRD,IR进行了结构表征,结果表明其均为5层的ABO_3结构.利用H_2-TPR考查了掺杂Mn以后样品的氧化还原性能的变化,发现由于Mn的掺杂使Cu明显的容易还原还考查了样品对NO+CO反应的催化活性,结果表明反应的活性中心是Cu离子,但加入适量的Mn离子可以使活性提高.
Resumo:
A novel organotin complex, EtPhSnCl(2) . 2HOC(10)H(6)CH = NC6H1OCH3 was synthesized, and its crystal structure was determined by X-ray diffraction method. The crystal is triclinic, belonging to space group,
with unit cell parameters a = 1.150 8(5) nm, b = 1. 153 1(5) gm, c = 1. 004 6 (3) nm, alpha = 94. 15 (3)degrees, beta = 115.47 (3)degrees, r = 85. 94 (4)degrees, V = 1199 7(1) nm(3), Z=2, D-c=1.68 g/cm(3), mu=13. 20 cm(-1), F(000)=618 for 4 131 reflections tions. R=0. 047, R(w)=0. 047. The ligand coordinates to tin atom via phenolic oxygen atom. The complex has a distored trigonal bipyramidal structure, the phenolic oxygen atom of the ligand and one of two chlorine atoms occupy the axial position. The distance between noncoodinated nitrogen atom with phenolic oxygen atom is 0. 257 4 nm, which indicates that the intramolecular hydrogen bond of Schiff base ligand is retained in the complex.
Resumo:
用循环线性电流扫描计时电位法和循环伏安法研究了双1∶11镝的硅钼杂多酸阴离子在水/硝基苯界面的转移。在pH=1.1~5.3时,转移离子为H9Dy(SiMo11O39)24-.根据循环伏安结果计算得转移离子的标准电位差和Gibbs转移自由能分别为0.102V和-39.5kJ·ml-1,并由循环线性电流扫描计时电位法计算了转移离子的有关动力学参数,H9Dy(SiMo11O39)24-在水/硝基苯界面的转移属准可逆转移.
Resumo:
合成了三茚基稀土配合物(η~5-C_9H_7)_3Ln·OC_4H_8(Ln=Nd、Gd、Er),经元素分析、红外光谱、水解产物核磁共振谱及质谱表征,并测得了(η~5-C_9H_7)_3Nd·OC_4H_8(1)及(η~5-C_9H_7)_3Gd·OC_4H_8(2)的晶体结构。(1)、(2)均属六方晶系,P6_3空间群,Z=2。(1)的晶体学参数为a=b=1.1843(3)nm,c=1.0304(4)nm,V=1.25165(87)nm~3,D_c=1.49g·cm~(-3),最后一致性因子R=0.049;(2)的晶体学参数a=b=1.1805(2)nm,c=1.0236(2)nm,V=1.23536(56)nm~3,D_c=1.54 g·cm~(-3),R=0.023。平均Nd-C=0.2812nm,Gd-C=0.2795nm;Nd-O=0.2557(21)nm,Gd—O=0.2459(13)nm。配合物中四氢呋喃的四个碳原子处于完全无序状态。
Resumo:
本文研究了甲基膦酸二(1-甲庚)酯(简称P350)的正庚烷溶液从盐酸溶液中萃取钪(Ⅲ)、HCl和H_2O的机理。用斜率法确定了萃合物的组成为SoCl_3·3P350和3HCl·2H_2O·3P350。讨论了水相酸度、萃取剂浓度、温度对萃取平衡的影响,计算了反应的浓度平衡常数及热力学函数。研究了萃合物的红外光谱。
Resumo:
1932年鲍林(Pauling)首次提出元素电负性概念,经化学家和物理学家长期运用与研究,其定义、计算方法、应用范围和理论根据等方面都得到了广泛发展与许多成功改进。
There are two 5 '-flanking regions of bkt encoding beta-carotene ketolase in Haematococcus pluvialis
Resumo:
The unicellular green alga Haematococcus pluvialis accumulates a commercially valuable astaxanthin, with levels reaching up to 4% dry weight under environmental stress. In recent years, much effort has been devoted to understanding the molecular mechanisms regulating astaxanthin biosynthetic pathways. Beta-carotene ketolase (bkt), with control being exhibited at the transcription level, plays an important role in astaxanthin biosynthesis by H. pluvialis. Here we demonstrate the presence of two separate 5'-flanking regions [1.5 kilobase (kb) and 2 kb] of bkt (bkt1 and bkt2) that possess regulatory elements similar to those of known stress-responsive genes in plants. Results of 5'-deletion constructs and transient beta-galactosidase expression assays demonstrate that there may be positive regulatory elements governing expression in the shorter promoter at -1060/-900 from the 1.5 kb 5' region, and in the longer promoter at -1838/-1219 and at -1046/ -734 from the 2 kb 5' region relative to each homologous ATG start codon. Furthermore, our present studies reveal that the first intron (+371/+497) downstream from the 1.5 kb 5' untranslated region of bkt1 may function as a negative regulatory element to regulate its own promoter.
Resumo:
A 700-year record (1.0-1.5 a resolution) of the East Asian winter monsoon (EAWM), based on grain-size analysis and AMS(14)C dating of Core EC2005 from the inner-shelf mud wedge of the East China Sea (ECS), was compared with the Dongge stalagmite delta O-18 record during the mid-Holocene. The upper muddy section of Core EC2005 has been formed mainly by suspended sediments derived from the Changjiang (Yangtze) River mouth since 7.3 ka BP. High precipitation and a strengthened EAWM might have played key roles in the high sedimentation rate (1 324-1 986 cm/ka) between 5.9-5.2 ka BP. The EAWM strengthened when the Asian summer monsoon weakened, especially around 5 500 a BP, which corresponded to a worldwide cold event. The EAWM during the mid-Holocene shows statistically significant solar periodicities at 62 and 11 a. The 5 500 a BP cold event might be resulted from orbital forcing and changes in solar activity.
Resumo:
Based on Th-230-U-238 disequilibrium and major element data from mid-ocean ridge basalts (MORBs) and ocean island basalts (OIBs), this study calculates mantle melting parameters, and thereby investigates the origin of Th-230 excess. (Th-230/U-238) in global MORBs shows a positive correlation with Fe-8, P (o), Na-8, and F-melt (Fe-8 and Na-8 are FeO and Na2O contents respectively after correction for crustal fractionation relative to MgO = 8 wt%, P (o)=pressure of initial melting and F (melt)=degree of melt), while Th-230 excess in OIBs has no obvious correlation with either initial mantle melting depth or the average degree of mantle melting. Furthermore, compared with the MORBs, higher (Th-230/U-238) in OIBs actually corresponds to a lower melting degree. This suggests that the Th-230 excess in MORBs is controlled by mantle melting conditions, while the Th-230 excess in OIBs is more likely related to the deep garnet control. The vast majority of calculated initial melting pressures of MORBs with excess Th-230 are between 1.0 and 2.5 GPa, which is consistent with the conclusion from experiments in recent years that D (U)> D (Th) for Al-clinopyroxene at pressures of > 1.0 GPa. The initial melting pressure of OIBs is 2.2-3.5 GPa (around the spinel-garnet transition zone), with their low excess Ra-226 compared to MORBs also suggesting a deeper mantle source. Accordingly, excess Th-230 in MORBs and OIBs may be formed respectively in the spinel and garnet stability field. In addition, there is no obvious correlation of K2O/TiO2 with (Th-230/U-238) and initial melting pressure (P (o)) of MORBs, so it is proposed that the melting depth producing excess Th-230 does not tap the spinel-garnet transition zone. OIBs and MORBs in both (Th-230/U-238) vs. K2O/TiO2 and (Th-230/U-238) vs. P (o) plots fall in two distinct areas, indicating that the mineral phases which dominate their excess Th-230 are different. Ce/Yb-Ce curves of fast and slow ridge MORBs are similar, while, in comparison, the Ce/Yb-Ce curve for OIBs shows more influence from garnet. The mechanisms generating excess Th-230 in MORBs and OIBs are significantly different, with formation of excess Th-230 in the garnet zone only being suitable for OIBs.
Resumo:
SNARE蛋白家族是所有真核细胞胞吐及分泌作用中的关键因子,由其介导的运输囊泡膜与靶膜的锚靠、融合为胞内蛋白的运出提供了一条重要途径。体外试验表明,Syntaxin6-Syntaxin7-Vti1b,SNAP-23-Syntaxin4等SNARE核心蛋白之间精确的相互作用是哺乳动物巨噬细胞肿瘤坏死因子α (TNF-α)运输和分泌的必备条件,在机体非特异性免疫应答反应过程中起重要作用。 本研究受上述启示,旨在揭示SNARE蛋白在海洋鱼类免疫细胞内重要细胞因子白细胞介素1β (IL-1β)的分泌过程中的作用。参照Percoll密度梯度离心技术,从鲈鱼头肾组织分离纯化巨噬细胞进行稳定培养;利用RT-PCR方法克隆出鲈鱼t-SNARE蛋白SNAP-23和Syntaxin3的部分cDNA序列,再结合先前克隆的VAMP2和已知的鲈鱼IL-1β,TNF-α和IL-8的基因序列,设计特异性引物。利用Real-time PCR技术在mRNA水平上精确测定鲈鱼巨噬细胞中上述6种基因在革兰氏阴性菌脂多糖(LPS)分子刺激下的表达变化,发现SNAP-23基因与三种细胞因子基因的表达正相关;通过免疫印迹检测SNAP-23蛋白表达变化,利用酶联免疫吸附试验(ELISA)检测IL-1β的分泌水平,在蛋白水平上验证了SNAP-23表达与IL-1β分泌的正相关性;利用5`RACE和3`RACE技术克隆出鲈鱼SNAP-23全长基因,结合定点突变策略和靶向PCR克隆手段,构建鲈鱼SNAP-23野生型融合质粒pEGFP-SNAP-23wt,Cys缺失突变融合质粒pEGFP-SNAP-23ΔCys和模拟E型肉毒神经毒素(BoNT/E)切割突变融合质粒pEGFP-SNAP-23ΔBoNT/E,以及鲈鱼IL-1β野生型融合表达质粒IL-1β-pEGFP和IL-1β-pEYFP。所有融合蛋白均在鲈鱼巨噬细胞内成功表达,结合ELISA实验结果发现,SNAP-23野生型的表达对IL-1β的分泌有促进作用,而Cys缺失突变体的表达则抑制IL-1β向胞外分泌。首次证实了鱼类巨噬细胞内SNAP-23蛋白在IL-1β分泌过程中的重要作用。此外通过与GFP共表达,定位了IL-1β分子在巨噬细胞内的分布,发现新合成的IL-1β分子很可能像TNFα一样经“内质网-胞质-伪足-胞外” 的分泌路径运出胞外。
Resumo:
南海是西太平洋最大的边缘海之一,位于欧亚板块、印-澳板块以及太平洋板块之间。南海海底扩张停止(15.5Ma, Briais et al., 1993) 后的板内火山作用,影响着中国南部、中南半岛、大洋基底和分裂的微大陆片段的广大地区。对南海新生代玄武岩进行地球化学研究,不仅对于理解南海板内火山作用的深部地幔过程有着重要意义,而且对南海形成演化及含油气盆地形成的深部动力学机制有着深远意义。 南海新生代玄武岩K-Ar/Ar-Ar年龄为3.8-7.9Ma, 表明为晚中新世以来的岩浆活动产物,与周边地区的碱性火山岩在年龄上的一致性。岩石学特征表明,南海新生代玄武岩的矿物组合为橄榄石、单斜辉石、斜长石,与特征的碱性玄武岩的矿物组合一致。由橄榄石所计算的南海底潜在地幔温度(Tp)平均值为1661℃, 暗示南海地区下的地幔可能存在热量异常,为海南地区存在地幔柱的观点提供了证据。单斜辉石富钙、钛,由单斜辉石-熔体平衡温压计计算的岩浆房深度分别为:碱玄岩岩浆房深度约49km(对应压力为1.46~1.48 GPa);粗面玄武岩岩浆房约25km(对应压力为0.76 GPa);玄武岩岩浆房约15km(对应压力为0.44GPa)。由碱玄岩→粗面玄武岩→玄武岩,平衡温度(K)依次降低:从1535~1498→1429→1369。由斜长石微晶所计算的岩浆喷出地表的温度为989℃。 主量元素特征表明,岩石类型主要为碱玄岩,有少量的粗面玄武岩和玄武岩,属于碱性系列。微量元素方面,大离子亲石元素(LILE)以及高场强元素(HFSE)特别是Nb、Ta、Ti、Y等元素均呈现富集现象,Yb、Sc、Sr以及K、U、Th等生热元素相对亏损,微量元素及稀土元素分布岩石类似板内OIB微量元素的全球平均值。同位素地球化学研究表明,源区存在两个混合端员并具Dupal Pb异常:一个为DMM,位于软流圈或岩石圈地幔中;另一个为EM2源区,可能来自位于核-幔边界处的海南地幔柱而非大陆底岩石圈地幔。研究表明,南半球Dupal异常不存在全球范围内的地区专属性,本区存在的Dupal异常与南半球Dupal异常可能不存在联系。在南海新生代玄武岩的成因过程中,海南地幔柱在为岩石圈地幔的部分熔融作用提供所需的热量同时,也在物质上作出了贡献。南海盆新生代碱性玄武岩由不同程度的部分熔融作用,以及岩浆在上升期间或者在高位岩浆房中的橄榄石等矿物分离结晶作用所形成,同时还可能发生了堆晶作用。构造环境判别表明,玄武岩浆在上升到地表过程中几乎未受到地壳混染。 南海新生代玄武岩的地球化学研究表明,在玄武质岩浆的深部地幔演化过程中,海南地幔柱可能起着重要的作用。通过引入海南岛地幔柱这个概念,本文建立了一个新的有关南海形成演化的初步的概念性模型:(1)50-32Ma,印度洋板块-欧亚板块碰撞及其所导致的太平洋板块后退的综合效应为南海地区提供了一个伸展环境,此伸展环境为地幔柱物质的上升提供了通道;(2)32-21Ma,当地幔柱柱头到达软流圈时, 通过侧向物质流开始同扩张中心发生相互作用,促进了南海的扩张,并在26-24Ma期间发生了洋脊重新就位事件,使扩张中心从原来的18°N附近(即现今西北海盆的中心)调整到15.5°N附近(即现今的东部亚盆);(3)21-15.5Ma, 随着地幔柱效应的逐渐增强,热点-洋脊相互作用越来越强烈,在大约21Ma发生了洋脊的再次重新就位事件,诱发了西南海盆的扩张;(4)15.5-现在,由于印澳板块前缘与巽他大陆碰撞,使得南海大约在15.5Ma停止扩张,并沿着南沙海槽及吕宋海沟向菲律宾岛弧及巴拉望地块之下俯冲,而南海热点继续活动,在地表处直到第四纪还有碱性玄武岩喷出。
Resumo:
In order to discover the distribution law of the remaining oil, the paper focuses on the quantitative characterization of the reservoir heterogeneity and the distribution law of the fluid barrier and interbed, based on fine geological study of the reservoir in Liuhuall-1 oil field. The refined quantitative reservoir geological model has been established by means of the study of core analysis, logging evaluation on vertical well and parallel well, and seismic interpretation and prediction. Utilizing a comprehensive technology combining dynamic data with static data, the distribution characteristics, formation condition and controlling factors of remaining oil in Liuhuall-1 oil field have been illustrated. The study plays an important role in the enrichment regions of the remaining oil and gives scientific direction for the next development of the remaining oil. Several achievements have been obtained as follows: l.On the basis of the study of reservoir division and correlation,eight lithohorizons (layer A, B_1, B_2, B_3, C, D, E, and F) from the top to the bottom of the reservoir are discriminated. The reef facies is subdivided into reef-core facies, fore-reef facies and backreef facies. These three subfacies are further subdivided into five microfacies: coral algal limestone, coralgal micrite, coral algal clastic limestone, bioclastic limestone and foraminiferal limestone. In order to illustrate the distribution law of remaining oil in high watercut period, the stratigraphic structure model and sedimentary model are reconstructed. 2.1n order to research intra-layer, inter-layer and plane reservoir heterogeneity, a new method to characterize reservoir heterogeneity by using IRH (Index of Reservoir Heterogeneity) is introduced. The result indicates that reservoir heterogeneity is medium in layer B_1 and B_3, hard in layer A, B_2, C, E, poor in layer D. 3.Based on the study of the distribution law of fluid barrier and interbed, the effect of fluid battier and interbed on fluid seepage is revealed. Fluid barrier and interbed is abundant in layer A, which control the distribution of crude oil in reservoir. Fluid barrier and interbed is abundant relatively in layer B_2,C and E, which control the spill movement of the bottom water. Layer B_1, B_3 and D tend to be waterflooded due to fluid barrier and interbed is poor. 4.Based on the analysis of reservoir heterogeneity, fluid barrier and interbed and the distribution of bottom water, four contributing regions are discovered. The main lies on the north of well LH11-1A. Two minors lie on the east of well LH11-1-3 and between well LH11-1-3 and well LH11-1-5. The last one lies in layer E in which the interbed is discontinuous. 5.The parameters of reservoir and fluid are obtained recurring to core analysis, logging evaluation on vertical well and parallel well, and seismic interpretation and prediction. Theses parameters provide data for the quantitative characterization of the reservoir heterogeneity and the distribution law of the fluid barrier and interbed. 6.1n the paper, an integrated method about the distribution prediction of remaining oil is put forward on basis of refined reservoir geological model and reservoir numerical simulation. The precision in history match and prediction of remaining oil is improved greatly. The integrated study embodies latest trend in this research field. 7.It is shown that the enrichment of the remaining oil with high watercut in Liuhua 11-1 oil field is influenced by reservoir heterogeneity, fluid barrier and interbed, sealing property of fault, driving manner of bottom water and exploitation manner of parallel well. 8.Using microfacies, IRH, reservoir structure, effective thickness, physical property of reservoir, distribution of fluid barrier and interbed, the analysis of oil and water movement and production data, twelve new sidetracked holes are proposed and demonstrated. The result is favorable to instruct oil field development and have gotten a good effect.
Resumo:
在密闭体系中, 400~700℃和1~3 GPa的条件下进行了褐煤加水的模拟实验, 分析了实验产物中芳烃的演化特征, 并讨论了高压高温对有机质的演化的影响. 实验结果表明, 高压抑制了液态烃的裂解, 压力升高有利于有机质降解产物的环化、聚合和芳构化; 温度升高, 芳烃的成熟度增加, 压力增加会抑制或延迟油气的生成和有机质成熟, 并且温度越低, 抑制作用越明显. 高压对有机质热演化的影响是非线性的. 该研究结果不仅加深了对俯冲带地幔有机质稳定性的认 识, 而且对认识深层油气成藏及保存也有启示意义.