排序方式: 共有39条查询结果,搜索用时 31 毫秒
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研究了用酸分解试样后不需分离基体直接用电感耦合等离子体原子发射光谱(ICP-AES)法测定铅锭中银、铜、铋、砷、锑、锡、锌、铁、镉、镍、铊11种杂质元素的方法。优化了样品前处理条件及仪器检测条件。方法的检出限为0.0012~0.0168μg/mL,回收率为89%~110%,RSD为2.3%~5.0%。方法简便快速,检出限低,精密度和准确度能满足铅锭中杂质元素的检测要求,具有较强的实用性和可操作性,可用于铅锭中杂质元素的测定。 相似文献
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We report on a novel technique which exploitsradiative recombination transitions for a direct experimental determination of the two-electron contributions to the ground state energy in heliumlike high-Z ions. Results are presented of a first experiment which was conducted at an electron beam ion trap for various elements ranging from Z=32 to 83. The comparison with theoretical predictions demonstrates that the achieved precision already provides a sensitive test of second order many-body contributions and approaches the size of the two-electron (screened) Lamb shift. The potential of the new technique will be outlined and the capability of the ESR storage ring for future investigations will be emphasized. 相似文献
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Gamma-ray decays of the 12.71 and 16.11 MeV states of 12C are investigated in a coincidence study of the 10B(τ, pγ) reaction, and using the 163 keV 11B(p, γ) resonance. This information together with existing data on M1 transitions and stripping and pickup spectroscopic factors is used to determine the isospin mixing between the 12.71 and 15.11 MeV levels. A charge dependent mixing matrix element of 110 ± 30 keV is deduced. 相似文献
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RE Tribble A Azhari HL Clark CA Gagliardi Y-W Lui AM Mukhamedzhanov A Sattaroy X Tang L Trache V Burjan J Cejpek V Kroha S Piskor J Vincour F Carstoiu 《Pramana》1999,53(3):585-594
S-factors for direct capture reactions can be found at astrophysical energies from asymptotic normalization coefficients which
provide the normalization of the tail of the overlap function. For example the overlap for 8B → 7Be+p defines the S-factor for 7Be (p, γ)8B. Peripheral transfer reactions offer a technique to determine these asymptotic normalization coefficients. As a test of
the technique, the 16O(3He, d)17F reaction has been used to determine asymptotic normalization coefficients for transitions to the ground and first excited
states of 17F. The S-factors for 16O(p, γ)17F calculated from these 17F → 16O+p asymptotic normalization coefficients are found to be in very good agreement with recent measurements. Following the same
technique, the 10B(7Be, 8B)9Be and 14N(7Be, 8B)13C reactions have been used to measure the asymptotic normalization coefficient for 7Be(p, γ)8B. This result provides an indirect determination of S
17(0). 相似文献
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为改善壳聚糖对细胞的特异性吸附,采用水溶性碳二亚胺将生物活性短肽精氨酸-甘氨酸-天冬氨酸-丝氨酸(RGDS)固定到壳聚糖膜的表面,采用X射线光电子能谱检测固定多肽前后的壳聚糖膜表面,发现反应后壳聚糖膜表面氮元素含量增大,Nls和Cls曲线拟合谱中酰胺键增多,表明RGDS短肽已固定到壳聚糖膜的表面;人角膜缘上皮细胞体外培养实验表明,固定RGDS后壳聚糖膜的细胞黏附率有了明显提高,固定RGDS后的壳聚糖膜在角膜组织工程支架等方面有更好的应用潜力。 相似文献
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Shan Yang Sanjay Adhikari Manoj Dobbala Sasidhar Adusumilli Joseph D. Rowley Feruz Ganikhanov Lingquin Zhang Glen Marrs Robert Wysolmerski George Spirou 《Applied physics. B, Lasers and optics》2013,111(4):617-625
We report on design of a multi-color laser set up that allows for high spectral, time and spatial resolution imaging based on second- and third-order optical nonlinearities in soft condensed matter. Two femtosecond optical parametric oscillators (OPOs) are pumped simultaneously to provide intrinsically synchronized pulses at more than a dozen tunable colors across visible and infrared wavelengths. We demonstrate the use of independently tunable OPOs in a variety of imaging modalities. In one useful application, we explore brain tissue in a two-photon absorption fluorescence imaging experiment with near infrared optical pulses (λ ~ 1,070 nm). We also demonstrate second and sum-frequency generation microscopies in different tissues. Results from application of time-resolved, three-color coherent anti-stokes Raman scattering in tissue are presented to demonstrate feasibility of quantitative spectroscopic imaging. 相似文献
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