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研究了微波等离子体炬原子发射光谱(MPT-AES)法测定高温合金中非金属元素(As、B、P、Si)的分析方法,考察此方法对高温合金行业非金属检测需求的适应性。对镍基高温合金样品进行酸溶解处理,选择适用的微波等离子体炬分析谱线,进行检出限、精密度测定。4种非金属元素的检出限在0.03~0.12μg/mL,10次数据的相对标准偏差(RSD,n=10)为0.88%~1.9%,此方法可用于高温合金中非金属元素的测定。 相似文献
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This paper is a continuation to our work (Xu et al. in Ann Henri Poincaré 18(1):53–83, 2017) concerning the persistence of lower-dimensional tori on resonant surfaces of a multi-scale, nearly integrable Hamiltonian system. This type of systems, being properly degenerate, arise naturally in planar and spatial lunar problems of celestial mechanics for which the persistence problem ties closely to the stability of the systems. For such a system, under certain non-degenerate conditions of Rüssmann type, the majority persistence of non-resonant tori and the existence of a nearly full measure set of Poincaré non-degenerate, lower-dimensional, quasi-periodic invariant tori on a resonant surface corresponding to the highest order of scale is proved in Han et al. (Ann Henri Poincaré 10(8):1419–1436, 2010) and Xu et al. (2017), respectively. In this work, we consider a resonant surface corresponding to any intermediate order of scale and show the existence of a nearly full measure set of Poincaré non-degenerate, lower-dimensional, quasi-periodic invariant tori on the resonant surface. The proof is based on a normal form reduction which consists of a finite step of KAM iterations in pushing the non-integrable perturbation to a sufficiently high order and the splitting of resonant tori on the resonant surface according to the Poincaré–Treshchev mechanism. 相似文献
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To determine the geometries of the most stable hept-C(62)X(2) (X = F, Cl, and Br) isomers, all 967 possible hept-C(62)F(2) isomers have been orderly optimized using AM1, HF/STO-3G, B3LYP/3-21G, and B3LYP/6-31G* methods, and chlorofullerenes and bromofullerenes, which are isostructural with five most stable hept-C(62)F(2) isomers, were regarded as candidates of the most stable isomer, and optimized at the B3LYP/6-31G* level. The results reveal that 2,9- and 9,62-hept-C(62)X(2) (X = F, Cl, and Br) are the two most stable isomers with slight energy difference. The halogenation releases strain energy of hept-C(62), and all halogenated fullerenes are more chemically stable than hept-C(62) with lower E(HOMO) and higher E(LUMO). All five most stable hept-C(62)X(2) (X = F, Cl, and Br) isomers are energetically favorable, and their thermodynamic stability decreases along with the increase of sizes of addends. Only hept-C(62)F(2) isomers show high thermodynamic stability, and they are potentially synthesized in experiments. 59,62-squ-C(62)X(2) (X = F, Cl, and Br) were computed for comparison, and they are found to be more stable than their heptagon-containing isomers. 相似文献
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Yingfei Zhou Yongqing Huang Xiaofeng Duan Xinye Fan Xiaomin Ren 《Optics & Laser Technology》2012,44(1):285-289
Flat-top and steep-edge spectral response of photodetectors is important for dense wavelength-division-multiplexed system. Realization of the flat-top and steep-edge response is very challenging. In the last two decades many methods have been proposed, but the spectral response linewidth is not acceptable to wavelength-division-multiplexes system. In this paper a novel RCE photodetector with flat-top and steep-edge spectral response is presented. Using the step shaped structure, designing multiple-step-type p-type In0.67Ga0.33As0.7P0.3 contact layer and adjusting the thickness of the absorption layer, a design with good flat-top performance is demonstrated such that the quantum efficiency is 51.161% in the flat-top passband, 0.5 and 3 dB bandwidths are 0.26 and 0.4 nm, respectively. 相似文献
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The effects of hindered amines, such as TMP, TMPM, TUV-770, on MMA and St homopoly-merization have been studied. It was found that in the MMA polymerization initiated with BPO orAIBN, the presence of TMPM, TUV-770 prolonged the induction period and a little change on R_p wasobserved. However, in the presence of TMP R_p increased slightly. The activation energy of poly-merization and polymerization rate equation were determined. 相似文献
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Yingfei Wang Wei Chen Zhong Wang Yu Zhu Hongxia Zhao Kun Wu Jie Wu Prof. Weihua Zhang Dr. Qing Zhang Prof. Hongqian Guo Prof. Huangxian Ju Prof. Ying Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(3):e202212866
Nanomotors are appealing drug carriers, and the strength of the propelling force is important for their motion capability. Though high motion efficiency has been achieved with 808 nm light driven Janus-structured noble metal nanomotors, the NIR-I light penetration depth and material biocompatibility limit their broad application. Herein, we develop a 1064 nm NIR-II light driven asymmetric hydrogel nanomotor (AHNM) with high motion capability and load it with doxorubicin for enhanced immunochemotherapy. Magnetic field assisted photopolymerization generates an asymmetric distribution of Fe3O4@Cu9S8 nanoparticles in the AHNM, producing self-thermophoresis as driving force under NIR-II irradiation. The AHNM is also functionalized with dopamine for the capture and retention of tumor-associated antigens to boost immune activation. The as-obtained NIR-II light driven AHNM has a high tumor tissue penetration capability and enhances immunochemotherapy, providing a promising strategy for cancer therapy. 相似文献