26 resultados para DÖ3


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利用142Nd(16O,5n)153Er和147Sm(16O,6n)157Yb反应并藉助与氦喷嘴快速带传输装置和x(γ) γt-符合测量技术首次建立了153Er和157Yb的(EC/β+)衰变能级纲图。 对153Er的(EC/β+)衰变纲图的分析,得到结果有, 1) 辨认了256.7KeV和634.2KeV的二条低位能级分别为d3/2和d5/2的单质子态。因此,153H0的基态 的形状为球形。在同位素链Ho(Z=67)上,随着中子数的增加,奇质量数Ho核的基态核形状由球形过渡到变形发生在中子数86和88之间。 2) 位于1700.1KeV能级为三粒子态,具有[(πh11/2 νh9/2)1+ νf7/2] , , 的结构特征。 经对157Yb的(EC/β+)衰变纲图分析,得到结果有, 1) 发现了建立在157Tm基态上的Kπ= 转动带的带头部分。用可变转动惯量的三轴行变粒子转子模型对157Tm的转动能谱的计算结果表明,157Tm的基态Kπ= 转动带所对应的形变是三轴形变,相应的形变参数为ε2=0.23,ε4=0.01,γ=35°。给出了随着中子数的增加,奇质量数Tm(Z=69)核的基态核形状由球形过渡到非球形发生在中子数86和88之间。 2) 辨认了一条位于激发能为3502KeV的同质异能态,其寿命>40ns。

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利用不同参数和函数,模拟了千烟洲人工林主要树种马尾松、湿地松和杉木的枝条、叶生物量和总生物量及单株各器官生物量,选择最佳函数计算生物量在各树种不同器官中的分配,估算不同林型的地上生物量.结果表明,不同树种的枝条基径(d)和枝条生物量(BW)、叶生物量(LW)之间,当d3为自变量时,相关系数最高,湿地松利用线性函数、马尾松和杉木利用幂函数模拟效果最佳;单木总生物量以利用D2H(胸径2×树高)为自变量的幂函数模拟相关系数最高;3个树种叶和枝生物量各有不同的最佳自变量和函数类型,但同一树种的叶、枝生物量最佳拟合方程的自变量和函数类型一致.马尾松林、湿地松林和杉木林的地上生物量分别为83·6、72·1和59t·hm-2,其中树干生物量所占比重最大,叶生物量最小.根据前人的研究结果推算3种林分地下生物量分别为10·44、9·42和11·48t·hm-2,其固碳量分别为47·94、45·14和37·52t·hm-2.

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以弱碱性苯乙烯系阴离子交换树脂 [D3 92 ,— NH2 ,D3 82 ,— NHCH3,D3 0 1 R,— NH(CH3) 2 ],强碱性苯乙烯系阴离子交换树脂 [2 0 1× 7DVB,— NH+ (CH3) 3]和弱碱性环氧系阴离子交换树脂 (70 1 ,— NH2 )为载体制备了 3种钯 -高分子载体催化剂 .考察了反应条件、高分子载体的种类、钯含量和催化剂用量对糠醛催化加氢生成四氢糠醇反应及催化性能的影响 .在体积分数为 5 0 %的乙醇 -水溶液和水中对糠醛常压液相加氢反应 ,钯 -高分子载体 (阴离子交换树脂 D3 92 ,— NH2 ,D3 82 ,— NHCH3)催化剂均可使糠醛的加氢反应转化率达 1 0 0 % ,生成四氢糠醇的选择性达 98%以上 ,而用金属钯为催化剂的转化率达 70 %以上 ,选择性达97%以上 .同时用 XPS分析了高分子载体催化剂的结构与催化加氢反应性能的关系.

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EuBa2(Cu1-xFex)3O7-y has been investigated by the Fe-57 and Eu-151 Mossbauer effect. The Fe-57 Mossbauer spectra of the EuBa2(Cu1xFex)3O7-y without or with DC electric current (the current strength I = 0.5A) around the superconducting transition temperature have been measured. The results indicate that the isomer shift (IS) and the quadrupole splitting (QS) of the Fe replacing the Cu(2) vary neither with increasing the Fe content nor with the small DC eletric current passing the superconductor and that the IS and the QS of the Fe replacing the Cu(1) vary with the Fe content. Especially, the IS and the QS of the Fe (D3) replacing the Cu(1) are changed when the small electric current passes the superconductor at 80K.

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Retinoid X receptor (RXR)/ultraspiracle (USP) is the heterodimeric partner of ecdysteroid receptor and is required for the molting process of arthropods. To better understand the molecular aspects governing the process of molting in shrimp, the full-length cDNA of two RXRs, named as FcRXR-1 and FcRXR-2 were obtained from Chinese shrimp Fenneropenaeus chinensis which were of 1715 and 1700 bp long, revealed a 1315 and 1300 bp open reading frame (ORF) respectively. Quantitative Real time PCR analysis showed a marked tissue-specific difference in the expression of FcRXR transcript, which revealed that the expression of FcRXR Could be regulated in a tissue-specific manner. Moreover, high expression of FcRXR mRNAs was observed in late pre-molt period (D3) and post molt stages (A-B) of shrimp. Among the two isoforms, FcRXR-2 appeared in a considerably high level in all the stages compared to the FcRXR-1. In addition, we examined the temporal expression of two chitinase genes: FcChitinase (FcChi) and FcChitinase-1 (FcChi-1) during the molt cycle of F chinensis. Both the FcChi and FcChi-1 transcripts were detected in all stages of molting, although considerable fluctuations observed through the molt cycle. Injection of double stranded RXR (dsRXR) into juvenile shrimp resulted in a maximum silencing effect at 48 h post injection. We analyzed the expression levels of FcChi, FcChi-1 and the ecdysone inducible gene E75 (FcE75) in samples of dsRXR injected shrimp. Significant reduction in levels of both FcE75, FcChi and FcChi-1 transcripts Occurred in the silenced shrimp. This correlation suggested that RXR might involve in the downstream regulation of E75 and chitinase gene transcription in the ecdysone signaling pathway of decapod crustaceans. (C) 2009 Published by Elsevier Inc.

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Ecdysone inducible gene. E75 is a primary target of ecdysone receptor (EcR). and is found to play a critical role in the molting process of arthropods In this study, a cDNA encoding the E75 of Chinese shrimp Fenneropenaeus chinensis (FcE75) was cloned using RT-PCR and RACE techniques FcE75 cDNA was 3611 bp in length with an ORF of 2394 bp. The deduced amino acid sequence of FcE75 had the highest sequence identity to E75 from a land crab Gecarcinus lateral's and E75 of the shrimp Metapenaeus crisis Quantitative real-time PCR revealed a prominently high expression of FcE75 mRNA in the whole body RNA extract of late premolt period (D3) juvenile shrimp. The role of E75 in the process of shrimp molting was investigated using the RNA interference technique Long double-stranded RNA corresponding to the FcE75 (dsE75) efficiently silenced the FcE75 transcript levels in juvenile F. chinensis. Further, injection with dsE75 completely arrested the molting process in experimental shrimp which eventually caused death Setogenic analysis of the uropods from molt-arrested shrimp, showed defective epidermal retraction, poor development of setae and new cuticle. These results indicate that E75 might be related to the molting process and is essential for proper molting and survival of shrimp This is the first report demonstrating the use of double stranded RNA to elucidate the possible role of E75 in the molting of decapod crustaceans (C) 2010 Elsevier Inc All rights reserved

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本论文主要研究两种重要的调节蜕皮过程的基因—蜕皮激素效应基因E75和RXR在中国明对虾蜕皮中的作用。利用RT-PCR和RACE技术获得了编码FcE75和FcRXR的全长cDNA序列。FcRXR包含7个内含子,在对虾中存在不同的异形体,命名为RXR-1和RXR-2。应用荧光实时定量PCR分析表明FcE75和FcRXR基因在中国明对虾蜕皮前期(D3)其转录表达量明显上调。另外,FcE75和FcRXR基因在不同组织中的转录表达存在明显的差异。利用FcE75和FcRXR基因的双链RNA注射对虾能有效降低FcE75和FcRXR的表达水平。FcE75和FcRXR的体内沉默完全抑制了对虾的蜕皮过程,并且引起对虾的死亡。对不能正常蜕皮个体进行观察的结果表明,FcE75沉默的对虾,其上皮的收缩、新的刚毛及新表皮的形成均收到限制。在FcE75双链RNA沉默后的对虾中,我们检测了与蜕皮相关的一些效应因子,如chitinase等的转录,发现这些效应因子的转录明显受到抑制,说明FcE75和FcRXR在蜕皮过程中起到非常重要的作用。本论文首次阐明了这些基因在十足目甲壳动物蜕皮过程中的功能。

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1植物名称麻花艽(Gentiana straminea Maxim.),又名麻花秦艽,藏药中称为"解吉嘎保".2材料类别幼嫩叶子.3培养条件愈伤组织诱导培养基:(1)MS+2,4-D3.0 mg•L-1(单位下同);(2)MS+2,4-D 3.0+KT 1.0.继代培养基:(3)MS+2,4-D 1.0+6-BA 0.5+NAA 0.5.分化培养基:(4)MS+NAA 1.0+6-BA 2.0+ZT 3.0.以上培养基均附加CH(水解酪蛋白)300、肌醇200、3%蔗糖、5 g•L-1琼脂粉,pH 5.8.培养温度为(25±1)℃,光源为日光灯,光强为30~60μmol•m-2•s-1,光照时间12 h•d-1.

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从抱茎獐牙菜的胚轴、幼叶及未成熟种子诱导出愈伤组织并再生植株,试验选用MS、B5 和N6 三种培养基,其中以附加2. 4 - D3. 0mg/ L + 6 - BA0. 5mg/ L的MS 培养基诱导率最高;以附加6 - BA0. 5mg/ L + NAA 0. 2mg/ L 的MS 培养基分化苗频率最高;以附加2. 4 - D2. 0mg/ L + 6 - BA0. 5mg/ L 的MS 培养基愈伤组织的生长最好。结果表明,外植体,培养基,激素等对愈伤组织诱导、继代和分化均有明显影响。采用高压液相色谱法(HPLC) 测定抱茎獐牙菜愈伤组织中齐墩果酸含量的结果表明,愈伤组织中齐果墩酸含量因培养基、继代培养时间的不同而有所差异。

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The Baoyintu Group, lies in Wulate-zhongqi, Inner Mongolia, is a set of medium-grade metamorphic rock series which undergoes complex deformations. It consists of pelite schist, greenschist, plagioclase amphibolite quartzite and marble. The pelite schist is the main rock type and contains the classic medium pressure metamorphic minerals. The author divided Baoyintu group into five assemblages, investigated the rock association and plotted geological section of each assemblage in this area. Based on the systemically study of structural geology, petrology, geochemistry and mineralogy, the author reconstructs the protolith, sedimentary environment and tectonic evolution, discusses the mesoscopic and microscopic structure, metamorphism, geochemistry characters and the correlation between porphyroblast growth and deformation-metamorphism. There are three phase deformations in the research area: the earliest one occurred as the Baoyintu group deformed and metamorphosed and the main structure pattern is tight fold within layers during the Dl, large scale reversed fold and two phase faults (Fl fault and F2 fault) during the D2, and superimposed fold and F3 fault during D3. The F3 trancate the Wenduermian group of Silurian. The second and third phase deformation are relate to the orogenic event of late period of early Paleozoic. According to the rock association ,characteristics of the rocks and research of geochemistry, we get some information of the sedimentary environment and tectonic evolution of Baoyintu group. The source rocks are a set of terrigenous deposits-volcanic formation which reflect the history of the tectonic setting: stable- active-restable. And there are two sedimentary cycle from first assemblage to fifth assemblage: from first assemblage to fourth assemblage is a course of progression and the fifth assemblage is a start of regression. We also get the information of the P-T-t path by studying petrographies and calculating temperature and pressure. The path is not similiat to any classic type. And the interpretation is different from the traditional opinion. The P-T-t path reflects the dynamic course of convergence and uplift, magma underplating, back-arc extension and convergence of continental margin. Applying the theory of deformation partitioning to this area, the author discuss the relationship between deformation and porphyroblast growth, and get the conclusion of the sequence of deformation and metamorphism. At the first time we measure the distribution of chemical composition within the porphyroblast by XRF, confirm the theory of deformation partitioning quantitative and get new understanding about growth phase of porphyroblast and growth mode of porphyroblast: porphyroblast grow in the manner as "rose flower", the growth is controlled by the deformation. The elements distribution in porphyroblast reflects the growth manner and indicate history of metamorphism and deformation. So, we can deduce the metmorphism and deformation from the elements distribution in porphyroblast.

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The conceptualization of “depression” as a heterogenous disease has been widely accepted by most researchers. However, controlled experiments are rather sparse. To date, most studies demonstrated that animals with helplessness, a widely recognized behavioral index of “depression” also show varied comobidity expressions of other emotional behaviors, such as hightened or lightened anxiety level compared with controls. This means that distinct subtypes of “depression” may exist, in which different neural mechanisms may play roles. The present study aims to explore the possibility of behaviorally categorizing two depressive subtypes, referred as anxious helplessness and non-anxious helplessness, respectively. Then, by using RT-PCR, the dopamine D1, D2, D3 receptors mRNA expressions in medial prefrontal cortex (mPFC) and nucleus accubems (NAc) were quantified. The main findings are described as belows: 1. Uncontrollable shock could readily induce helpless behavior in shocked animals as a whole but with salient individual differences. Prior inescaoable shock induces subsuquent helplessness in approximately 40% shocked animals, while the other animals showed no sign of helpless expression, and were classified as non-helplessness. 2. Among helpless animals, the “subtype” of anxious helpless and non-anxious helpless could be identified according to the anxiety level evaluated by elevated plus maze. 3. D3 receptors mRNA expressions in the mPFC and NAc were increased in stressed animals after uncontrollable shock treatment. At the meanwhile, significant lower expressions of D2 receptors in the mPFC and NAc, and much lower expressions of D1 receptors in the mPFC were found in rats that did not become helpless after stress. In contrast, no significant difference between helpless and control animals was found in D1/D2 receptors mRNA expressions. 4. Based on above mentioned results, the up-regulation of D3 receptors in the mPFC and NAc may reflect a generalized effect of exposure to uncontrollalbe shock. While the down-regulation of D1\D2 receptors in the mPFC and decreased expression of D2 receptors in the NAc may be associated with adaptive or protective mechnisms which protecting animals from helplessness after uncontrollable shock treatment. 5. Futhermore, a significant negative relationship was found between anxiety level and D1 receptors expressions in the mPFC in helpless animals. Compared to the non-anxious helpless and control rats, the D1 receptors mRNA of anxious helpless rats were down-regulation in the mPFC. The present study indicated that the D1 dopamine receptor gene is associated with co-morbid depression and anxiety.