997 resultados para Tintoretto, 1518-1594.
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以土垫旱耕人为土为供试土壤,采用大田试验,研究了半湿润农田两种杂草处理方式下(成熟后期清除杂草-A区和苗期开始清除杂草-B区),不同施氮量对夏玉米产量及氮素利用效率的影响。结果表明,当施氮量为0、45、90、1351、80 kg/hm2时,B区玉米子粒产量比A区分别增加了8.7%、12.1%、9.4%、5.0%和12.5%;吸氮量分别增加了1.5、2.9、4.85、.2和4.3 kg/hm2。A区和B区全生育期0—100 cm土层矿质氮(Nmin)累积量变化趋势基本一致,但B区比A区变幅较大。当施氮量为45、90、135和180 kg/hm2时,B区氮肥利用率、氮肥农学利用率、氮肥生理利用率均高于A区。研究还发现,在A区,当施氮量为180 kg/hm2时,杂草干生物量最大,为1518.3 kg/hm2,不施氮时,杂草的生物量最低,为845.7 kg/hm2;杂草的吸氮量随施氮量的增加而增加。可见,清除玉米农田杂草不仅可以提高作物产量和氮肥利用率,而且在减少氮素损失方面具有一定作用。
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为了改进现有防伪数码相机不能处理通过翻拍伪造数码照片的缺陷,提出了一种新的基于安全芯片的防伪数码相机架构。在拍摄时将所拍摄的区域分成多个小单元,并用对焦测距系统测量各个单元到相机的距离。用安全芯片对图像元数据、图像内容及距离信息进行数字签名,并将签名内容及距离信息都保存在图像文件的元数据里。通过验证数字签名有效且距离信息不完全相等来保证图片的真实可信。该防伪数码相机能同时发现照片在拍摄后被篡改和翻拍问题,所拍摄照片真实可信。
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Graphite, inexpensive and available in large quantities, unfortunately does not readily exfoliate to yield individual graphene sheets. Here a mild, one-step electrochemical approach for the preparation of ionic-liquid-functionalized graphite sheets with the assistance of an ionic liquid and water is presented. These ionic-liquid-treated graphite sheets can be exfoliated into functionalized graphene nanosheets that can not only be individuated and homogeneously distributed into polar aprotic solvents, but also need not be further deoxidized. Different types of ionic liquids and different ratios of the ionic liquid to water can influence the properties of the graphene nanosheets. Graphene nanosheet/polystyrene composites synthesized by a liquid-phase blend route exhibit a percolation threshold of 0.1 vol % for room temperature electrical conductivity, and, at only 4.19 vol %, this composite has a conductivity of 13.84 S m(-1), which is 3-15 times that of polystyrene composites filled with single-walled carbon nanotubes.
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It has been found that charge compensated CaMoO4:Eu3+ phosphors show greatly enhanced red emission under 393 and 467 nm-excitation, compared with CaMoO4:Eu3+ without charge compensation. Two approaches to charge compensation, (a) 2Ca(2+) -> EU3+ + M+, where M+ is a monovalent cation like Li+, Na+ and K+ acting as a charge compensator; (b) 3Ca(2+) -> 2EU(3+) + vacancy, are investigated. The influence of sintering temperature and Eu3+ concentration on the luminescent property of phosphor samples is also discussed.
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Catalytic reactions with different oxidation process were investigated and correlated to the electrochemical properties of the catalysts. The activity of suprafacial reaction is closely related to the area of redox peak, while that of the intrafacial one is to the match of redox potentials. Accordingly, it is supposed that cyclic voltammetry (CV) measurement could be a means for predicting the oxidation process in heterogeneous catalysis.
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目的采用共聚的方法改变聚酯的结构,探讨材料结构与生物相容性的关系,为临床选用适宜性质的该类材料提供实验依据。方法将自行合成的聚己内酯(PCL)、聚丙交酯(PLA)、以及它们不同摩尔比的共聚物(PCLA2/1、PCLAI/2)植入兔背部肌肉中24周,观察动物生活和整体情况;组织学和组织计量学方法观察材料周围肌肉的组织学情况,比较不同结构材料的组织相容性。结果材料在整个植入周期所呈现的组织反应是一种无菌性非特异炎症反应;周围纤维包膜厚度依次增厚,肌肉中的炎细胞数量依次增加。结论不同结构材料的生物相容性存在差异。
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Two new sesquiterpenes, 15-hydroxy-T-muurolol (3d) and 11,15-dihydroxy-T-muurolol (3e), along with the plant cadinenes T-muurolol (3f) and 3 alpha-hydroxy-T-muurolol (3g), were isolated from the marine-derived Streptomyces sp. M491. Their absolute configuration was established via NMR spectroscopy and X-ray crystallography of 3-oxo-T-muurolol (3a), which was reisolated from this strain. In addition, the absolute configuration of further sesquiterpenes previously reported from this strain was revised. These products were tested for their cytotoxicity against 37 human tumor cell lines using the MTT method. Only 3d was cytotoxic against a range of human tumor cell lines with a mean IC50 of 6.7 mu g/mL.
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热休克蛋白70是热休克蛋白家族中重要的成员,参与新生蛋白的折叠、转运、重折叠变性蛋白、协助降解变性蛋白和抗逆环境胁迫等功能。海带和裙带菜是浅海潮下带典型的褐藻,孔石莼和浒苔是潮间带典型的绿藻,四种大型海藻均有重要的经济价值和生态价值。随着潮汐变化固着藻类生境理化因素变化剧烈,藻类面临着严重的环境胁迫,因此研究藻类抗逆机理有着重要的意义。 本研究采用同源克隆法配合RACE-PCR,克隆了海带、孔石莼、裙带菜和浒苔HSP70基因的全序列(分别命名为LJHSP70、UPHSP70、QDHSP70和EPHSP70)。利用生物信息学方法分析了四种藻类HSP70结构特征、同源性关系和进化地位。获得的海带HSP70基因全序列长为2918 bp,5’非翻译区为248 bp,3’非翻译区为696 bp,开放阅读框为1974 bp,编码657个氨基酸,预测的分子量为72.03 kDa,等电点为4.97。获得的裙带菜HSP70基因全序列长为3243 bp,5’非翻译区为248 bp,3’非翻译区为1021 bp,开放阅读框为1974 bp,编码657个氨基酸,预测的分子量为72.03 kDa,等电点为4.96。获得的孔石莼HSP70基因全序列长为2283 bp,5’非翻译区为65 bp,3’非翻译区为247 bp,开放阅读框为1971 bp,编码656个氨基酸,预测的分子量为71.13 kDa,等电点为5.04。获得的浒苔HSP70基因全序列长为2265 bp,5’非翻译区为65 bp,3’非翻译区为217 bp,开放阅读框为1983 bp,编码660个氨基酸,预测的分子量为71.39 kDa,等电点为5.03。四种海藻HSP70氨基酸序列均含有四肽重复序列GGMP,具有三个典型的HSP70签名基序。细胞质定位的HSP70 C-末端特征基序为EEID或EEVD,并且N-端氨基酸序列保守性高于C-端。海带和裙带菜HSP70蛋白同源性为98%,孔石莼和浒苔HSP70蛋白同源性为96%,四种海藻HSP70蛋白序列与陆地植物和其他藻类HSP70蛋白序列同源性为70-80%。 利用荧光定量RT-PCR技术对不同胁迫条件处理的海带和孔石莼HSP70 mRNA的表达水平进行定量分析。不同热激温度(5-40 ℃)处理组中,30 ℃处理组的海带HSP70 mRNA表达量最高是10 ℃处理组的海带HSP70 mRNA表达量的3倍,而35 ℃或40 ℃处理组的海带HSP70表达量却低于25 ℃或30 ℃处理组的海带HSP70 mRNA表达量。25 ℃不同热激时间(0-12 h)处理组中,海带HSP70 mRNA表达量呈先上升后下降趋势。热激1 h后海带HSP70 mRNA表达量迅速上升,热激7 h后mRNA表达量达到最大,是对照组表达量的4倍。不同盐度(0‰-45‰)胁迫处理组中,0‰或5‰盐度处理组的海带HSP70 mRNA表达量是30‰盐度处理组海带HSP70 mRNA表达量的3倍。35‰、40‰和45‰盐度处理组之间HSP70 mRNA表达量较低且无显著差异。 不同热激温度(5-40℃)处理组中,20 ℃或25 ℃处理的孔石莼HSP70 mRNA表达量较低,而5 ℃、35 ℃、或40 ℃处理组的孔石莼HSP70 mRNA的表达量是25 ℃处理组孔石莼HSP70 mRNA表达量的2倍以上。30 ℃不同热激时间(0-12 h)处理组中,孔石莼HSP70 mRNA表达量也呈先上升后下降趋势。热激5 h后孔石莼HSP70 mRNA表达量达到最大,是对照组的3.5倍。不同盐度(0‰-45‰)胁迫处理组中,0‰或5‰盐度处理组的孔石莼HSP70 mRNA表达量是30‰盐度处理组孔石莼HSP70表达量的3倍。30‰、40‰和45‰盐度处理组孔石莼HSP70 mRNA表达量较低,且无显著差异。不同紫外线照射时间(0-4.0 h)和不同干燥时间(0-4.0 h)处理组中,孔石莼HSP70 mRNA表达量都在3 h后达到最高值,之后表达量维持在较高水平。 为进一步研究藻类HSP70的生物学功能,将海带HSP70基因的开放阅读框区域克隆到表达载体pEASY-E2中,并转化到大肠杆菌BL21(DE3)pLysS。将阳性重组子培养于含有AMP(100 U/mL)的LB培养基,IPTG诱导表达,SDS-PAGE电泳鉴定。经5 h诱导,其表达量达到平台期,继续培养HSP70表达量并不显著增高。5 mM IPTG诱导海带HSP70蛋白表达量高于1 mM IPTG诱导蛋白表达量。
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Four novel triazole compounds containing thioamide group were designed and synthesized by using triazole, phenyl isothiocyanate and aryl ethyl ketone as raw material. Their structures were conformed by elemental analysis, H-1 NMR, IR and MS spectra. The crystal structure of 1-[1-anilinothiocarbonyl-1-(4-fluorobenzoyl)methyl]-1,2,4-trizole has been determined by X-ray diffraction analysis. The preliminary bioassays have shown that the title compounds exhibit certain antifungal activity.
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在氢氧化锂存在下,脱镁叶绿酸-a甲酯(1a)发生空气氧化和重排反应,经盐酸酸化和重氮甲烷甲基化,得到由紫红素-7三甲酯(2)、紫红素-18甲酯(3)、卟吩-P6三甲酯(4)、地质卟啉衍生物(5)和3-环氧乙基-3-去乙烯基紫红素-18甲酯(6)所组成的混合物.用相同的方法处理焦脱镁叶绿酸-a甲酯(1b),则分离出13^2-氧代焦脱镁叶绿酸-a甲酯(7)、15-甲酰基紫红素-5二甲酯(8)、紫红素-18甲酯(3)和3-环氧乙基-3-去乙烯基紫红素-18甲酯(6)-所得新叶绿素衍生物5,6和8的化学结构均经UV,IR,^1H NMR及元素分析得以证实,并对相应的反应提出可能的反应机理.
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Based on the features of soft soil in Tianjing Coastal New Developing Area, this kind of soil with different content of sand was researched systematically, according to the indoor experiment, about its characteristics of strength and deformation. The main results are summarized in the following: Firstly, on the basis of geological engineering investigation, the systemic experiments about the physical characteristics were conducted. The test soil samples were taken from the gray and gray-yellow silty soft soil which was formatted by near-shore marine sediment and marine-continental interactive sediment. The original condition of the sample soil was in saturation and the basic indexes are: liquid limit36.1%, plastic limit 18.8%, plasticity index. Then, the condensation characteristics of the soft soil were analyzed through high-pressure consolidation tests. The results show that,in various loading serials, the coefficient of compressibility under P=100kPa and 200kPa are all larger than 0.5MPa-1. So the sample soil is a kind of high-compressibility soil. Secondly, triaxial strength of undisturbed soil and remoulded soil was researched by using triaxial test. The types of stress-strain curve of both undisturbed and remoulded soil are the stress stabilization and softening type, which show the specific plastic character. Furthermore, the cohesion and friction angle of undisturbed soil changes, when the ambient pressure is different, instead of a stable value for all time; the cohesion and friction angle of remoulded soil changes with the compactness and sand-carrying capacity which is wholly higher than undisturbed soil. At last, the stress-strain results of both undisturbed and remoulded soil were normalized by using the ambient pressure as the normalization factor. The results show that, there are all some normalization characters in both undisturbed and remoulded soil, however, the feature of normalization of undisturbed soil is worse than the remoulded ones. The main reason is that the undisturbed samples are worse in equality and the unavoidable disturb through the process of sampling and experiments will also make them can not put up good normalization. Therefore, it is feasible to normalize the soil in Tianjing Coastal New Developing Area with the ambient pressure as normalization factor.
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Abstract:Little fundamental work on petroleum exploration and production of Zuunbayan Subbasin, Mongolia has been done before because of the backward economy and petroleum industry techniques in this country, which also results in our little knowledge of reservoir characteristics of this area. This paper focused on the sedimentary system, sedimentary facies, reservoir characteristics and their genesis distribution of Zuunbayan subbasin with various drilling, well logging, seismic, coring and outcrop data, aiming at providing significant guidances for the petroleum exploration and production of Zuunbayan area. Therefore, several conclusions have been achieved as follows: ①In Zuunbayan Subbasin, there are two chief source areas with Tarkhyata and Totoshan Uplifts in the southeast and Saykhandulaan Uplift in the west, respectively, while two subsidiary ones in the northeast and southwest of this subbasin. The sedimentary system of alluvial fan-fan delta is formed in the southeast highland, meanwhile braided river-braided river delta develops in the western ramp region and fan delta in the southern palaeohigh. ②There are middle to high permeability reservoirs in the upper Zuunbayan Formation and the upper member of lower Zuunbayan Formation meanwhile low-porosity and permeability to ultra-low permeability ones in Tsagaan Tsav Formation and the middle and lower members of lower Zuunbayan Formation. Combing with sedimentary facies belt, oil sources conditions and tectonic settings, favorable reservoir belts have been proved to be existing in the fan delta front reservoirs of lower Zuunbayan – Tsagaan Tsav Formation in the central uplift faulted zone as well as the braided river front ones of lower Zuunbayan-Tsagaan Tsav Formation in Zuunbayan nose anticlinal structural belts. ③The reservoir lithologic composition is complex and also related to volcanic activities. Generally, the types of lithologic composition in Zuunbayan Subbasin are chiefly feldspathic litharenites with low compositional maturity and high-middle textural maturity. The rock constituents from upper Cretaceous to lower Zuunbayan Formation are mainly metamorphic rocks including cleaving stone, phyllite, quartzite and schist while volcanic tuffs and acidic extrusive rocks are the secondary; and in the Tsagaan Tsav Formation are mainly volcanic tuffs with subsidiary cleaving stone, phyllite, quartzite and schist. ④In this paper, high-quality reservoirs in the upper member of lower Zuunbayan Formation have been discovered in the drilled high production wells of favorable reservoir facies through sedimentary system and sedimentary facies research, which benefits the prospect and also will bring a new life for petroleum exploration and production of Zuunbayan Subbasin. Key words: sedimentary system, sedimentary facies, superior quality reservoir, Zuunbayan Subbasin, lower Zuunbayan Formation