46 resultados para Tintoretto, 1512-1594.


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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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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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利用电喷雾质谱研究了β-环糊精、七-(2,6-二-O-甲基)-β-环糊精作为手性识别试剂对1,1'-联萘酚对映体的手性识别效应.实验结果表明,在气相中,β-环糊精与七-(2,6-二-O-甲基)-β-环糊精都可以与联萘酚形成非共价复合物.对形成的复合物的串联质谱研究表明,β-环糊精不能识别联萘酚对映体,而七-(2,6-二-O-甲基)-β-环糊精对联萘酚对映体有较强的手性识别效应.进一步研究表明七-(2,6-二-O-甲基)-β-环糊精与联萘酚对映体混合比例以及CID能量对于手性识别并无影响.

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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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β-羧乙基锗倍半氧化物(Ge-132)的无毒广谱抗癌作用以及潜在的治疗艾滋病的功能~[1~3]促进了Ge-132及其衍生物合成及生物活性研究~[4~6],而对锗原子直接与苯环及其衍生物连接的有机锗倍半氧化物的研究则相对较少.我们曾报道了~[7]p-(二甲氨基)苯基锗倍半氧化物的合成、结构及对癌细胞的作用,p-(二乙氨基)苯基锗倍半氧化物的研究尚未见报道.本文采用改进的方法合成了p-(二乙氨基)苯基锗倍半氧化物(Ge-164).通过元素分析、IP、XPS和TG-DTA确定了组成和结构,观察了它对体外培养人乳腺癌细胞有丝分裂的影响.

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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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Penaeid shrimp, as an invertebrate, relies on the innate immunity to oppose the microbial invaders. Antimicrobial peptides (AMP) are an integral component of the innate immune system in most organisms and function as an early first line of defense against pathogens, but the knowledge about the pathways to regulate the shrimp AMP gene expression is still absent up to date. In the current study, a Relish homolog (FcRelish) was cloned from Chinese shrimp Fenneropenaeus chinensis. The full length cDNA of FcRelish consists of 2157 bp, including 1512 bp open reading frame, encoding 504 amino acids. The predicted molecular weight of FcRelish is 57 kDa, and the theoretical PI is 7.00. Spatial expression profiles showed that FcRelish had the highest expression levels in the hemocytes and lymphoid organ. Both Vibrio anguillarium and Micrococcus lysodeikticus stimulation to shrimp can affect the transcription profile of FcRelish. Silencing of FcRelish through DsRNA interference can greatly change the transcription profile of AMP. Therefore, we suggest that FcRelish identified in the present study is closely related to the transcription of AMP, and then we inferred that Imd pathway might exist in shrimp. (C) 2009 Elsevier Ltd. All rights reserved.

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对虾流行病爆发以来,我国乃至世界的对虾产业一直受到各种虾病的困扰,对虾养殖业严重受阻。解决这一问题的关键是加强对虾免疫机制的研究,并在此基础上寻找对虾疾病防治的有效方法。Rel/NF-κB是一类核转录因子,在无脊椎动物的先天性免疫中,起着极为重要的作用。 本论文根据其他无脊椎动物中NF-κB家族基因Relish和Dorsal的保守氨基酸序列分别设计简并引物,从中国明对虾血细胞cDNA中先后克隆到了Relish和Dorsal基因的部分片段,并结合SMART-RACE技术分别获得了中国明对虾Relish基因(FcRelish)和Dorsal基因(FcDorsal)的cDNA 全长。 FcRelish的cDNA 全长为2157个碱基,其中开放阅读框为1512个碱基,编码504个氨基酸;FcRelish蛋白的推导分子量为57373.5 Da,理论等电点为7.00。FcDorsal基因的cDNA 全长为1627个碱基,其中开放阅读框为1071个碱基,编码357个氨基酸;FcDorsal蛋白的推导分子量为39780.7 Da,理论等电点为8.85。 分析了FcRelish基因和FcDorsal基因的在血细胞、淋巴器官、肠和肌肉等12个组织中的表达水平。组织表达结果表明FcRelish和FcDorsal在淋巴器官和血细胞中表达水平明显高于其他组织,而淋巴器官和血细胞是对虾免疫系统中最重要的两个组织,由此可以推测中国明对虾中的Relish和Dorsal可能与免疫关系密切。 本论文还利用实时荧光定量PCR技术,对灭活鳗弧菌刺激,以及WSSV病毒刺激后,对虾血细胞和淋巴器官中FcRelish基因和FcDorsal基因的转录水平进行了研究。FcRelish基因在WSSV病毒刺激后,在血细胞和淋巴器官中都出现了波浪形变化,说明FcRelish对WSSV病毒刺激产生了应答。在灭活鳗弧菌刺激后,FcRelish在血细胞中变化不明显,而在淋巴器官中出现了两次明显的下调上调交替,出现这种现象的具体原因有待探究。在WSSV病毒刺激后,血细胞和淋巴器官中FcDorsal的转录表达呈波浪形变化。而在鳗弧菌刺激后,FcDorsal在血细胞和淋巴器官中的转录均在短时间内出现明显的上调表达,说明FcDorsal对鳗弧菌非常敏感。 作为核转录因子的NF-κB蛋白的转录激活作用需要在细胞质中通过蛋白水解作用来激活,为了进一步阐明NF-κB对病菌感染的应答机制,需要进一步研究这两种转录因子在蛋白水平的变化,以便从分子水平阐明NF-κB在对虾天然免疫中的作用。

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在实验室内建立了Oshima 提出的针对麻痹性贝毒毒素的高效液相色谱分析方法,并根据实验室条件对分析过程进行了完善.同时对另一重要的麻痹性贝毒分析方法-Thielert分析方法进行了改进,在保持原方法对neoSTX, dcSTX 和STX等毒素较高分辩率和检出限的基础上, 提高了原方法中GTX1 和GTX4,GTX3和GTX2的分辩率,使之可以分析已知的大多数麻痹性贝毒毒素.应用建立的高效液相色谱技术对从中国南海海域分离的两株塔玛亚历山大藻ATHK 和ATCI03的毒素含量及组成进行了分析,结果表明两株塔玛亚历山大藻均能产生毒素,但在毒素组成和含量方面存在明显差别。批次培养结果表明每细胞毒素含量在对数生长期初期最高,之后逐渐降低。以两株有毒藻中毒素含量较高的ATHK 作为模型,研究了光照强度、盐度以及营养盐(N,P)对有毒藻生长和毒素产生的影响。结果表明在实验光照强度内(2100lux-4700lux),塔玛亚历山大藻的生长速率随光照强度的增加而增加,对相同细胞密度的藻采样分析结果表明毒素含量在场300Lux最大;而在同一天取样分析的结果表明毒草素含量随光照强度的降低而增加。在实验盐度下相差不大。而毒素含量在职4S相对偏低。一次培养结果表明,在氮、磷营养盐充足的条件下,毒素今是在对数生长初期达到最高,之后逐渐降低,起始时较低的氮浓度对对数生长初期毒素含量影响不大,但对数生长期中后期的细胞内毒素含量明显降低。而起始时较低的磷浓度则使对数期中后期的细胞内毒素含量保持稳定或逐渐增加。培养液中氮、磷的供应情况直接决定细胞骨毒素含量的变化;而培养液起始磷比在决定细胞毒素含量弯化方面也有一定的作用。半连续培养结果表明氮限制恒化培养使每细胞毒素含量降低,而磷限制恒化培养使每细胞毒素含量升高,营养充足的恒浊培养得到的藻细胞毒素今是介于二者之间。通过分析氮、磷限制下半连续恒化培养的塔玛亚历山大藻细胞内毒素含量、精氨酸水平、谷氨酰胺/谷氨酸比值(Gln/Glu)等,研究了营养盐对毒素产生的影响机制。结果表明,细胞内毒素含量与精氨酸水平以及Gln/Glu比值存在明显相关关系。在此基础上提出了氮、磷对毒素产生可能的影响机制。即外界环境中的氮通过影响细胞内精氨酸水平而影响毒素含量;磷则是通过改变细胞的氮代谢途径而影响毒素的合成。磷的缺乏可能导致细胞正常的代谢停滞,为缓解细胞内氮过剩造成的毒性效应,作为氨基酸合成重要中间产物的谷氨酰氨转向合成精氨酸,造成精氨酸累积,累积的精氨酸双进一步生成麻痹性贝毒毒素。缺磷条件下毒素含量的增加很可能是对磷缺乏导致的细胞内氨积累的一种缓解措施.

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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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Geothermal resource is rich in Guanzhong Basin, but as to its cycle characteristic, there has been lack of systematic study so far. Blind exploitations lead to water-temperature reducing, the decrease of spring flow rate and so on. Based on groundwater system and hydrogeological and hydrological geochemical theory, this paper studied the recycling type of geothermal water and analyzed the resources of dissolved inorganic carbon (DIC) and sulfate. The origin of the internal geothermal water is ice and snow in Qinling Mountain and Liupan Mountain above 1400m. The precipitation and surface water entered the deep part of the basin along piedmont faults, heated and water-expansion increased. The karst groundwater comes from meteoric water of the bare carbonate rock area in the North Mountains. Geothermal-water DIC mainly came from the dissolution of carbonate rock in the deep part of Guanzhong Basin, sulfate of Xi’an depression and Lishan salient came from the dissolution of continental evaporate , and sulfate of Gushi depression and Xianli salient came from co-dissolution of continental and marine evaporate. The above results supply science basis for reasonable exploitation and sustainable utilization of the geothermal water in Guanzhong Basin.