964 resultados para Cs-natrolite


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A new methodology is proposed in this paper to predict the lowest power consumption for a double-tube-socket (DTS) pneumatic conveying system. This methodology is established on both experimental work and numerical simulation. After parametric studies by numerical simulation, the desired conveying cases which have the lowest power consumption were obtained. Finally those cases were carried out in our experimental system. The measured power consumption was close to that predicted. In this paper the experimental work is discussed and the numerical simulation introduced. (c) 2010 Elsevier B.V. All rights reserved.

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A pipeline with a bypass is widely used for the pneumatic conveying of material. The double-tube-socket (DTS (R)) technology, which uses a special inner bypass, represents the current state of the art. Here, a new methodology is proposed based on the use of computational fluid dynamics (CFD) to predict the energy consumption of DTS conveying. The predicted results are in good agreement with those from pilot-scale experiments. (C) 2010 Elsevier Inc. All rights reserved.

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本论文由三章组成。第一章介绍了中药蜘蛛香的化学成分的研究成果,第二章为羧甲基魔芋葡苷聚糖-壳聚糖为细胞膜的天冬酰胺酶人工细胞的研究,第三章综述了人工细胞在生物医学领域的应用。 第一章报道了中药蜘蛛香(Valeriana wallichii)根部乙醇提取物的化学成分,采用正、反相硅胶层析等分离方法和MS、NMR等多种波谱手段,从中共分离鉴定出17个化合物,分别为缬草素(valtrate,1),valechlorine(2),homobadrinal(3),baldrinal(4),乙酰缬草素(acevaltrate 5),valeriotetrate C(6),valeriotetrate B(7),对羟基苯乙酮(4'-hydroxy-acetophenone 8),7-hydroxy valtrate(9),8-methylvalepotriate(10),1,5-dihydroxy-3,8-epoxyvalechlorine A(11),二氢缬草素(didrovaltrate 12),胡萝卜苷(13),橙皮苷 (hesperidin 14),prinsepiol-4-O-β-D-glucopyranoside(15),longiflorone(16),乙基糖苷(17)。其中化合物6、7、10、和11为新化合物,化合物9、15、16为首次从该植物中得到。新化合物11为含有氯原子的刚性骨架环烯醚萜,并且确定了其绝对构型。 第二章报道了以羧甲基魔芋葡苷聚糖(CKGM)和壳聚糖(CS)为膜的固定化L-天冬酰胺酶人工细胞研究成果。利用羧甲基魔芋葡苷聚糖和壳聚糖两种生物相容性很好的天然多糖之间的静电吸引力,在非常温和的条件下制备成具有半透过性膜的人工细胞,将治疗儿童急性成淋巴细胞性白血病(ALL)的药物L-天冬酰胺酶包裹在内。通过考察温度和pH对人工细胞的影响,结果表明以CKGM- CS为膜的L-天冬酰胺酶人工细胞对温度和pH的稳定性和耐受性均高于自由酶,说明CKGM-CS对酶具有保护作用,而且小分子底物和产物可以自由进出膜内外,而包裹在膜内的生物大分子则不能泄露出来。 第三章综述了微囊化人工细胞的研究进展。 This dissertation consists of three parts. In the first part, the chemical constituents from the root of Valeriana wallichii were reported. In the second part, preparation and characteristics of L-Asparaginase Artificial cell were reported. The third part is a review on progress of microcapsule artificial cell. The first chapter is about the isolation and identification of the chemical constituents from the root of V. wallichii. Seventeen compounds were isolated from the ethanol extract of roots of V. wallichii through repeated column chromatography on normal and reversed phase silica gel. By the spectroscopic and chemical evidence, their structures were elucidated as valtrate (1), valechlorine (2), homobadrinal (3), baldrinal (4), acevaltrate (5), valeriotetrate C (6), valeriotetrate B (7), 4'-hydroxy-acetophenone (8), 7-hydroxy valtrate (9), 8-methylvalepotriate (10), 1,5-dihydroxy-3,8-epoxyvalechlorine A (11), didrovaltrate (12), daucosterol (13), hesperidin (14), prinsepiol-4-O-β-D-glucopyranoside (15), longiflorone (16), and ethyl glucoside (17). Among them, 6, 7, 10, and 11 are new compounds. 15, 16 and 9 were isolated from this plant for the first time. The absolute configuration of compound 11, an unusual iridoid bearing a C-10 chlor-group and an oxo-bridge connecting C-3 and C-8 resulting in a rigid skeleton, was confirmed. The second chapter is about the semi-permeable microcapsule of carboxymethyl konjac glucomannan-chitosan for L-asparaginase immobilization. Carboxymethyl konjac glucomannan-chitosan (CKGM-CS) microcapsules, which have good biocompatibility, prepared under very mild conditions via polyelectrostatic complexation, were used for immobilize L-asparaginase-a kind of drug for acute lymphoblastic leukemia (ALL). The activity and stability under different temperature and pH of the enzyme loaded-microcapsules were studied. The results indicated the immobilized enzyme has better stability and activity contrasting to the native enzyme. The study illustrates that the L-asparaginase could be protected in CKGM-CS microcapsules, the substrate and product could pass through the system freely.

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介绍了兰州重离子加速器冷却存储环(HIRFL-CSR)为重离子治癌而改造的控制系统中的数据交互系统,数据交互系统是CSR虚拟加速器的核心。该系统能实现对256个能量级的束流控制,为以后深层重离子治癌做好准备。系统主要采用Java,COM,Oracle,ARM,DSP,FPGA等技术实现了对磁铁电源的实时、同步控制,已达到对束流的控制及束流在不同能量级间的切换控制。该系统已经运行于冷却存储环主环(CS-Rm)的束流慢引出调试中,性能稳定,能满足物理人员的要求。

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用47MeV/nucleon的12C离子轰击133Cs靶,产生许多种不同元素的同位素。利用经典的化学分离方法,从大量的Cs和其它反应产物混合物中分离出I、Ba和Ce等。使用离线γ谱学方法,完成I、Ba、Ce等样品的γ活性测量。根据每种元素不同同位素的特征γ射线峰的强度和丰度,对I、Ba和Ce等样品中杂质的含量进行分析。结果显示该流程对杂质元素去污的效果是满意的。

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对中国科学院近代物理研究所自行生长的铊激活碘化铯闪烁晶体CsI(T1)光输出及Hamamtsu公司生产的S8664-1010型雪崩光二极管(APD)增益对温度的依赖关系做了系统研究.结果表明,CsI(T1)晶体光产额在室温范围内随着温度的增加而增加,在-2℃—8℃温度范围内的平均温度系数为0.67%/℃,在8℃—25℃温度范围内的平均温度系数为0.33%/℃.而对所使用的APD,其增益在室温范围内的温度系数为-3.68%/℃(工作电压400V).APD结合CsI(T1)晶体在室温下对~(137)Cs的662keYγ射线的能量分辨可达5.1%.

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介绍了 4 π多探测器阵列上的第一次中能重离子实验的电子学与数据获取系统。4 π多探测器为快慢塑料探测器和快塑料闪烁体 + Cs I的 Phoswich探测器组成 ,通过电荷数字转换 (QDC)分别记录探测器快慢信号 ,实现粒子的鉴别。在逻辑电路中 ,对前后角探测器分别给出 Trigger信号、QDC的清零信号和快慢公共门信号等。结果表明 ,前角探测器从质子、氘、氚、3 He、4He一直到 S、P等均可分辨

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利用 HIRFL (兰州重离子研究装置 )产生的 5 5 Me V/ u的4 0 Ar17+ 离子束 ,用由 Cs I(Tl) +快塑料闪烁探测器组成的 Phoswich探测器 ,以 1.5 mm有机玻璃为等效生物组织材料 ,探索了研究等效生物组织中核碎片测量的方法。对实验中可能出现的问题及解决方法进行了探讨。结果表明探测器对 Z可分辨到 16。元素分辨率为 Z/ ΔZ约为 4 0。

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描述了一个 5× 5阵列带电粒子 PHOSWICH闪烁探测器望远镜结构。它的每一个单元由 1片厚度为 1mm,面积为 2 4 mm× 2 4 mm快塑料闪烁体 NE10 2 A和 1个前表面为 2 4 mm× 2 4 mm,后表面为 37mm×37mm,厚度为 4 0 mm的 Cs I( Tl)晶体组成的。在兰州放射性离子次级束流线 ( RIBL L )上测试到 Z/ΔZ =2 0

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The excited states in 22Mg have been investigated by the resonant elastic scattering of 21Na + p. A 4.0 MeV/nucleon 21Na beam was separated by the Center for Nuclear Study (CNS) radioactive ion beam separator (CRIB) and then used to bombard a thick (CH2)n target. The energy spectra of recoiled protons were measured at scattering angles of θc.m. ≈ 172◦ , 146◦, and 134◦, respectively. A wide energy-range of excitation function in 22Mg (up to Ex ∼ 8.9 MeV) was obtained simultaneously with a thick-target method, and a state at 7.06 MeV was newly observed. The resonant parameters were deduced from an R-matrix analysis of the center-of-mass (c.m.) differential cross-section data with a SAMMY-M6-BETA code. The astrophysical resonant reaction rate for the 18Ne(α,p)21Na reactionwas recalculated based on the present parameters. Generally speaking, the present rates are much smaller than the previous ones.

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The temperature dependences of the light output of CsI(Tl) crystal grown at IMP and of the gain of the Hamamatsu S8664-1010 avalanche photodiode (APD) have been investigated systematically. The light output of the CsI(Tl) crystal increases with temperature by 0.67%/degrees C in the region from -2 degrees C to 8 degrees C, and by 0.33%/degrees C in the region from 8 degrees C to 25 degrees C, while the gain of the tested APD decreases by -3.68%/degrees C (working voltage 400V) on average in the room temperature range. The best energy resolution 5.1% of the CsI(Tl) with APD was obtained for the 662keV gamma ray from Cs-137 radiation source.

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Within an extended chiral constituent quark model, the three- and five-quark structure of the S-01 resonance Lambda(1405) is investigated. Helicity amplitudes for electromagnetic decays [Lambda(1405)->Lambda(1116)gamma, Sigma(1194)gamma] and transition amplitudes for strong decays [Lambda(1405)->Sigma(1194)pi, K- p] are derived, as well as the relevant decay widths. The experimental value for the strong decay width, Gamma(Lambda(1405)->(Sigma pi)degrees) = 50 +/- 2MeV, is well reproduced with about 50% of a five-quark admixture in the Lambda(1405). Important effects owing to the configuration mixing among Lambda P-2(1)A, Lambda P-2(8)M, and Lambda P-4(8)M are found. In addition, transitions between the three- and the five-quark components in the baryons turn out to be significant in both radiative and strong decays of the Lambda(1405) resonance.

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The axial charges of the proton and N(1440) are studied in the framework of an extended constituent quark model (CQM) including qqqq (q) over bar components. The cancellation between the contributions of qqq components and qqqq (q) over bar components gives a natural explanation to the experimental value of the proton axial charge, which can not be well reproduced in the traditional CQM even after the SU (6) circle times O(3) symmetry breaking is taken into account. The experimental value of axial charge pins down the proportion of the qqqq (q) over bar component in the proton to about 20%, which is consistent with the ones given by the strong decay widths and helicity amplitudes. Besides, an axial charge for N(1440) about 1 is predicted with 30% qqqq (q) over bar component, which is obtained by the strong and electromagnetic decays.