992 resultados para 194-1197B


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青稞(Hordeum vulgare L.var.nudum Hook.f.),即裸大麦,是兼食用、饲用和酿造于一体的作物,有着重要的利用价值。淀粉是青稞籽粒中含量最多、最重要的碳水化合物,淀粉含量、直支淀粉比将会直接影响淀粉的功能特性,进而影响淀粉的应用领域。我国青藏高原青稞的栽培和食用历史悠久,特色青稞资源极其丰富。目前关于青藏高原青稞淀粉特性的报道还不多见,筛选和培育特色淀粉青稞利于拓展青稞的应用领域, 从而提高其经济价值。 本研究以114份青藏高原青稞品种(系)为实验材料,通过SDS-PAGE对材料的胚乳淀粉颗粒结合蛋白(SGAPs)进行分离,确定各蛋白的分子量大小、组合类型和多态性等。然后按照国标法测试材料的籽粒总淀粉含量和直链淀粉含量,通过微型糊化粘度仪分析相应的淀粉糊化特性,最后使用显微镜观察比较了青稞的淀粉颗粒形态特征。主要结果如下: 1、114种青稞中共分离出20种不同的SGAP条带,条带分子量为35.00~112.39 KDa,分布频率为12.28~97.37%。材料含有的SGAPs条带数从10到14不等,超过一半的材料含11种SGAP条带。20种条带形成16种组合类型,其中西藏地区青稞包含所有16个组合类型,四川地区青稞包含其中12个组合类型。青藏高原青稞籽粒淀粉颗粒结合蛋白的差异很大,遗传多样性丰富。 2、114份青稞的总淀粉含量、直链淀粉含量、直支淀粉比、峰值粘度、糊化温度和峰值温度的变幅分别为51.26~66.70%、14.64~29.74%、0.17~0.42、194~1135BU、58.8~65.2℃和81.4~92.4℃,相应的平均值分别为59.82%、23.60%、0.31、722.30BU、62.1℃和88.8℃。群体在总淀粉含量、直链淀粉含量、直支淀粉比、峰值粘度、糊化温度和峰值温度上的分布具有明显的正态性;所有胚乳淀粉体的淀粉粒都呈复粒结构。对西藏和四川的材料进行了分组比较, 两地区的青稞在直链淀粉含量和直支淀粉比上的差异达到显著水平。 3、筛选出18份具有特殊淀粉特性的青稞品种,其中5份材料的总淀粉含量超过65%,包括NB63-1、NB67、甘孜白六棱、98221-1和NB63;3份材料的直链淀粉含量大于29%,包括藏青85、藏青3号和喜马拉6号;8份材料的直支淀粉比小于0.25,包括99033-6、春青稞、阿坝330、Jan-03、米麦114、396、NB63-1和92013;7份材料的糊化温度低于60℃,同时材料的峰值粘度大于1000BU,并且峰值温度低于90℃,包括足捉春、Jan-03、阿坝330、米麦114、春青稞、20003和阿青5号。 4、各淀粉特性间存在高度相关性。直链淀粉含量和直支淀粉比与糊化温度成极显著正相关,与峰值粘度成极显著负相关,与A型淀粉粒数量和大小呈负相关。不同SGAPs组合的品种之间,淀粉含量和淀粉糊化特性间差异均达显著水平。SGAP2、SGAP5、SGAP6和SGAP7可能对籽粒直链淀粉含量、直支淀粉比和糊化温度有正向效应;SGAP3、SGAP9∼SGAP20可能对峰值粘度有正向效应。 本研究对青藏高原青稞淀粉资源进行了较为全面的评价,对该区青稞淀粉特性有了系统的认识。研究筛选出的特殊青稞品种可作为青稞育种和青稞淀粉工业应用的潜在资源,淀粉特性差异巨大的众多青稞品种也为拓宽青稞应用领域提供了丰富的资源保障。本研究对部分SGAPs在性质上的鉴定和功能上的初步推断为青稞材料的筛选提供了指导,也为品质育种提供了理论参考。 Hulless barley (naked barley, Hordeum vulgare L.) is a short- season, early maturing crop with a wide range of adaptation. It has been attracting more and more attention due to its superior nutrition and extensive industrial applications. Starch is the main ingredient in hulless barley seeds which makes up 65 percent of hulless barley’s dry weight. The ratio of the amylose/amylopectin and the size, shape, distribution of starch granules can affect the physico-chemical and functional properties of starch, which may turn affect its utilizations. The Qinghai-Tibet Plateau, which is located in southwestern China, is a typical area of vertical agricultural ecosystem and one of the barley origin centers with abundant hulless barley resources. There are little reports about hulless barley in Qinghai-Tibet Plateau at present. To screen and cultivate some characteristic hulless barley can improve its value. An improved SDS-PAGE was used to identify SGAPs combination of 114 hulless barley varieties. Starch content (total starch and amylose starch) was determined according to the standard methods GB5006-85 and GB/T 15683 using PerkinElmer M341 Precision Automatic Polarimeter and UV spectrophotometer 755B respectively. The pasting properties were measured by BRABENDER Micrio Visco-Amylo- Graph 803201. The morphology of starch granules were observed and compared with Axioplan 2 Imaging light microscopy. The following were the results obtained: 1. There were 20 major SGAPs presented in 114 varieties, with the molecular weight ranged from 35.00 to 112.39 KDa, and the frequencies ranged from 12.28% to 97.37%. The number of SGAP bands in each accession varied from 10 to 14, more than half of the population had 11 bands. There were 16 distinct SGAP patterns in the 114 varieties, the Tibet hulless barley had all of the 16 types and the Sichuan hulless barley had 12 types. The results indicated the Qinghai-Tibet Plateau hulless barley had a polymorphism of the SGAPs. 2. The ranges of the total starch content, amylose content, Am/Ap, peak viscosity, pasting temperature and peak temperature of the 114 hulless barley were 51.26~66.70%,14.64~29.74%,0.17~0.42,194~1135BU,58.8~65.2 and 81.4℃~92.4, with an average of ℃59.82%, 23.60%, 0.31, 722.30BU, 62.1 and 88.8,℃℃ respectively. The distributions of the total starch content, amylose content, Am/Ap, peak viscosity, pasting temperature and peak temperature were visibly normal school. All of the amyloplasts in endosperm of varieties showed bimodal size distributions.The main starch properties of hulless barley from Tibet and Sichuan were separated and compared, the differences on amylose content and Am/Ap were obvious. 3. Eighteen accessions which had special starch properties were screened out. Five accessions with total starch content beyond 65%, including NB63-1, NB67, Ganzibailiuleng, 98221-1 and NB63; three accessions, Zangqing85, Zangqing3 and Ximala6, with the highest amylose content (>29%); five accessions with Am/Ap less than 0.25, including 99033-6, Chun Qingke, A Ba 330, Jan-03, Mi Mai114, 396, NB63-1 and 92013; seven accessions had a pasting temperature under 60, ℃meanwhile their peak viscosity beyond 1000BU and their peak temperature under 90℃,including Zu Cuochun, Jan-03, A Ba 330, Mi Mai 114, Chun Qingke, 20003 and A Qing 5. 4. There were high correlations between starch properties. Amylose content and Am/Ap were positively correlated to pasting temperature, negatively correlated to peak viscosity, negatively correlated to the number and granule size of A-type granule. Different SGAP combinations caused significant diversities in starch content and pasting properties. SGAP2, SGAP5, SGAP6 and SGAP7 may have positive effect on amylose content, Am/Ap and pasting temperature; SGAP3, SGAP9∼SGAP20 may have positive effect on peak viscosity. Our research made a comprehensive evaluation on the hulless barley starch from the Qinghai-Tibet Plateau, we can get a systemic understanding. Some special accessions were screened out can be used on the hulless barley breeding lines and industries utilization.The combination of the SGAPs may become a criterion to evaluate the hulless barley endosperm starch quality. Consequently, the results will be good information for further studies on the hulless barley.

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Beam matching relationship between the two cyclotrons(SFC and SSC) of HIRFL is briefly discussed, and the frequency band of the new RF cavity is obtained. The new cavity is simulated with the three-dimensional electromagnetic calculation code MAFIA, and the parameters of it such as frequency, Q value, shunt impedance and voltage distribution are worked out and discussed. The simulation results show that the new RF cavity can fully meet the requirements of physics design and space configuration.中文摘要:简要分析了HIRFL SFC与SSC之间的束流匹配关系,给出了新高频腔的频率范围。利用经典三维电磁场数值模拟软件MAFIA对SSC新高频腔体进行了模拟计算,得出了SSC新高频腔体的相关物理参数,并对频率范围、Q值、并联阻抗和电压分布等参数进行了分析。高频腔体的模拟计算结果完全符合SSC回旋加速器改造的物理设计及空间结构要求。

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考虑角动量相关性的情况下计算了超重核259Db的裂变位垒Bf。计算了258Rf,259Db,266Hs和267Mt 4个超重核单中子蒸发的存活概率Wsur及其随角动量分波的变化关系。给出了中子蒸发宽度、裂变宽度和超重核蒸发一个中子的概率对激发能与角动量分波的依赖关系。

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利用能量为 1 6 7— 1 75MeV的35Cl束流 ,通过16 0 Gd(35Cl,5n)熔合蒸发反应研究了190 Tl的高自旋态能级结构 .实验建立了190 Tl基于πh9/2    νi13/2 组态的转动带 .在束测量结果和194 Biα衰变的α γ测量结果确定地指定了190 Tl的πh9/2    νi13/2 转动带的自旋值 .基于自旋指定 ,发现了190 Tl的πh9/2    νi13/2 扁椭球转动带在低自旋时旋称反转 .这是首次在基于πh9/2    νi13/2 组态的扁椭球转动带中观测到旋称反转 .考虑了质子 -中子剩余相互作用的粒子 -转子模型能够解释πh9/2    νi13/2 扁椭球转动带的低自旋旋称反转 .

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中能重离子碰撞(10-100 MeV/u)为研究热核性质提供了有力的工龄。为此我们利用HIRFL提供的46.7 MeV/u ~(12)C束轰击~(159)Tb/~(197)Au/~(209)Bi研究了线动量转移分析、出平面角分布和质量分布,实验结果的分析证实了非完全熔合核的裂变和蒸发。编写了一个Monte-Carlo统计衰变程序(SAGEE)并用于详细比较C+Au、C+Bi的实验数据,C+Tb的质量分布由统计两体发射理论(GEMINI)得到了解释。理论与实验的符合说明:通常类熔合反应方式形成了高激发的复合核,其后以统计两体衰变而退激。实验也统计了与裂变符合的γ能谱、三裂变的相对角度和相对速度分布,没有观察到GDR,对称三裂不是唯一的三裂方式。本文分析了HIRFL上其他小组的实验结果。研究了46.7MeV/u ~(12)C+~(58)Ni反应的复杂粒子发射,也研究了复杂粒子出射对用放射化学方法测量的24MeV/u ~(12)C+~(64)Cu和42MeV/u ~(12)C+~(115)In的质量产额分布的解释。GEMINI计算很好地符合了实验结果,这意味着非完全熔合反应形成的复合核的两体衰变仍是主要的发射过程。本文也简要讨论了多重碎裂过程。基于卡西尼亚卵形体裂变形状,计算了转动核的对称和非对称形变势能,用此模型得到了核的静态裂变位垒、鞍点能并与RLDM和RFRM作了比较。我们考虑了YPE核势对核表面的弥散作用以及弥散核表面对库仑能、转动惯量的影响完善了RCOM,我们的RFCOM比RLDM和RFRM都有明显的改进,可以用于重核裂变性质研究。发展了熔合-裂变过程的宏观模型,计算了形成复合核~(149)Tb、~(194)Hg的熔合过程及其相应的裂变过程。本工作对研究热核的形成及其衰变性无疑是很有用的

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It was explored by density functional calculations that exchanged La or P species exert great influence on the local Al sites as well as on the adjacent exchanged species. In partially exchanged La- or P/H-ZSM-5 zeolite, some of the Al sites will fall off from the zeolite framework even more easily than in H-form ZSM-5, consistent with our XRF experiments. However, when exchanged by both La and P species, Al at either of the two exchanged sites shows better stability compared to H-from. zeolite. La and P species will interact strongly with each other, as evidenced by the charge donation process and the shortening of P-O-1 bond length. It was just the cooperation of La and P species that enabled RSCC catalysts worked normally under severe conditions. (C) 2004 Elsevier B.V. All rights reserved.

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The acid sites in dealuminated HZSM-5 zeolite with crystal sizes down to the nanoscale were firstly characterized by the probe molecule trimethylphosphine (TMP). As evidenced by the combination of P-31 CP/MAS NMR, Al-27 MAS and H-1 --> Al-27 CP/MAS NMR measurements, the Bronsted acid sites of both microsized and nanosized HZSM-5 could be decreased upon the dealumination of zeolitic framework after hydrothermal treatment. At the same time, the appearance of Lewis acid sites was observed. The dealuminated nanosized HZSM-5 is easier to form Lewis acid sites than microsized HZSM-5, and the type of Lewis acid sites in nanosized HSM-5 is more than one. In addition, the origin of Lewis acid sites is mainly associated with the aluminum at ca. 30 ppm, in the Al-27 MAS NMR spectra, and only a part of which in the dealuminated HZSM-5 zeolite acts as Lewis acid sites. (C) 2002 Elsevier Science B.V. All rights reserved.

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