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991.
《Journal of separation science》2018,41(11):2453-2460
A method for the determination of 16 polycyclic aromatic hydrocarbons in water has been developed. First, we made a solid‐phase extraction column. After this, the parameters affecting the efficacy of the experimental method were optimized, including appropriate selection of a solid‐phase extraction column and cleanup conditions on columns. The separation was achieved by gas chromatography and detection with triple quadrupole tandem mass spectrometry. The method showed satisfactory linearity (R2 > 0.999) over the range assayed (0.01–1 μg/mL), and limits of quantification ranging from 0.0011 to 0.0199 μg/L. The recoveries ranged from 83 to 113%. The relative standard deviation is in the range 0.86–3.1%. The results indicated that this method had high selectivity and precision that was suitable for the simultaneous determination of 16 polycyclic aromatic hydrocarbons in water. 相似文献
992.
采用阶变缓冲层技术 (step-graded) 外延生长了具有更优带隙组合的倒装GaInP/GaAs/In0.3Ga0.7As(1.0 eV) 三结太阳电池材料, TEM和HRXRD测试表明晶格失配度为2%的In0.3Ga0.7As 底电池具有较低的穿透位错密度和较高的晶体质量, 达到太阳电池的制备要求. 通过键合、剥离等工艺制备了太阳电池芯片. 面积为 10.922 cm2 的太阳电池芯片在空间光谱条件下转换效率达到32.64% (AM0, 25 ℃), 比传统晶格匹配的 GaInP/GaAs/Ge(0.67 eV) 三结太阳电池的转换效率提高3个百分点.
关键词:
太阳电池
三结
倒装结构 相似文献
993.
994.
In terms of the operator Nambu 3-bracket and the Lax pair (L, Bn) of the KP hierarchy, we propose the generalized Lax equation with respect to the Lax triple (L, Bn, Bm). The intriguing results are that we derive the KP equation and another integrable equation in the KP hierarchy from the generalized Lax equation with the different Lax triples (L, Bn, Bm). Furthermore we derive some no integrable evolution equations and present their single soliton solutions. 相似文献
995.
The tunneling dynamics of superfluid Fermi gas in a triple-well potential in the unitarity regime is investigated in the present paper. The fixed points of the (0, 0) mode and the (∏, ∏) mode are given. We find that the interaction parameter U and the coupling strength k could have an extreme effect on the quantum tunneling dynamics. We also find that, in the zero mode, only Josophson oscillation appears. However, for the ∏ mode, the trapping phenomena take place. An irregular oscillation of the particle number in each well could appear by adjusting the scanning period T* . It is noted that if the scanning period is less than a critical point T , the particle number will come back to the fixed point with small oscillation, while if T T* the particle number cannot come back to the fixed point, but with irregular oscillations. The dependence of the critical point T* on the system parameter of coupling strength k is numerically given. 相似文献
996.
Yukio Imanishi Naoki Kawazoe Kensuke Ichizawa 《Journal of polymer science. Part A, Polymer chemistry》2003,41(22):3632-3639
In expectation of the formation of a thermally stable, dielectric supramolecular assembly of a polypeptide with an amino acid sequence similar to that of type-2 collagen, a sequential polypeptide consisting of the repetition of the Pro-Pro-Gly tripeptide was synthesized by solid-phase synthesis. Column chromatography of an ethanol solution of (Pro-Pro-Gly)10 NH2 showed the presence of a double helix or triple helix of the polypeptide. The pattern of a circular dichroism (CD) spectrum of an ethanol solution of (Pro-Pro-Gly)10 NH2 was very similar to that of an aqueous solution of (Pro-Pro-Gly)10 OH, strongly suggesting the presence of a triple helix of the polypeptide in ethanol. An oriented monolayer assembly of (Pro-Pro-Gly)10 NH2 was formed on a thin gold film. The distribution of surface unevenness and the surface potential were investigated with Kelvin force microscopy. The rising spots carried an electric potential from room temperature to 150 °C. The correspondence showed the usefulness of the oriented monolayer of the sequential polypeptide materials for thermally stable, dielectric nanodevices. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3632–3639, 2003 相似文献
997.
We prove that the strengthened Hanna Neumann conjecture, on the rank of the inter-section of finitely generated subgroups of a free group, holds for a large class of groups characterized by geometric properties. One particular case of our result implies that the conjecture holds for all positively finitely generated subgroups of the free group F(A) (over the basis A), that is, for subgroups which admit a finite set of generators taken in the free monoid over A. 相似文献
998.
G. L. Silver 《Journal of solution chemistry》2003,32(7):637-643
The oxidation number and the pH are used to construct a predominance-region diagram for soluble plutonium. Features of the diagram can be verified by means of rearrangement equations for plutonium. 相似文献
999.
The new silver(I) triple salt 2Ag2C2·AgF·9AgNO3·H2O was prepared by dissolving Ag2C2 in an aqueous solution of AgNO3 and AgBF4. Its crystal structure contains two kinds of monocapped trigonal prismatic C2@Ag7 cages, with the capping atom occurring on one triangular face or one rectangular face. 相似文献
1000.
We define the notion of Connes-von Neumann spectral triple and consider the associated index problem. We compute the analytic Chern-Connes character of such a generalized spectral triple and prove the corresponding local formula for its Hochschild class. This formula involves the Dixmier trace for II∞ von Neumann algebras. In the case of foliations, we identify this Dixmier trace with the corresponding measured Wodzicki residue. 相似文献