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101.
In this paper, the authors discuss a generalization of Lappan’s theorem to higher dimensional complex projective space and get the following result: Let f be a holomorphic mapping of ? into Pn(C), and let H1, · · · , Hq be hyperplanes in general position in Pn(C).Assume that sup {(1 ? |z|2)f?(z) : z ∈ q[ j=1 f?1(Hj )o < ∞,if q ≥ 2n2 + 3, then f is normal.  相似文献   
102.
A reasonable prediction of photofission observables plays a paramount role in understanding the photofission process and guiding various photofission-induced applications, such as short-lived isotope production, nuclear waste disposal, and nuclear safeguards. However, the available experimental data for photofission observables are limited, and the existing models and programs have mainly been developed for neutron-induced fission processes. In this study, a general framework is proposed for characterizing the photofission observables of actinides, including the mass yield distributions (MYD) and isobaric charge distributions (ICD) of fission fragments and the multiplicity and energy distributions of prompt neutrons (np) and prompt γ rays (γp). The framework encompasses various systematic neutron models and empirical models considering the Bohr hypothesis and does not rely on the experimental data as input. These models are then validated individually against experimental data at an average excitation energy below 30 MeV, which shows the reliability and robustness of the general framework. Finally, we employ this framework to predict the characteristics of photofission fragments and the emissions of prompt particles for typical actinides including 232Th, 235, 238U and 240Pu. It is found that the 238U(γ, f) reaction is more suitable for producing neutron-rich nuclei compared to the 232Th(γ, f) reaction. In addition, the average multiplicity number of both np and γp increases with the average excitation energy.  相似文献   
103.
104.
One important prerequisite for the fabrication of molecular functional device strongly relies on the understanding the conducting behaviors of the metal-molecule-metal junction that can respond to an external stimulus. The model Lewis basic molecule 4,4′-(pyridine-3,5-diyl)dibenzonitrile (DBP), which can react with Lewis acid and protic acid, was synthesized. Then, the molecular conducting behavior of DBP, DBP-B(C6F5)3, and DBP-TfOH (DBP-B(C6F5)3, and DBP-TfOH were produced by Lewis acid and protonic acid treatment of DBP) was researched and compared. Given that their identical physical paths for DBP, DBP-B(C6F5)3, and DBP-TfOH to sustain charge transport, our results indicate that modifying the molecular electronic structure, even not directly changing the conductive physical backbone, can tune the charge transporting ability by nearly one order of magnitude. Furthermore, the addition of another Lewis base triethylamine (of stronger alkaline than DBP), to Lewis acid-base pair reverts the electrical properties back to that of a single DBP junction, that is constructive to propose a useful but simple strategy for the design and construction of reversible and controllable molecular device based on pyridine derived molecule.  相似文献   
105.
Xu  Yifan  Zhang  Hehe  Ding  Tangjing  Tian  Ruiqi  Sun  Dongmei  Wang  Ming-Sheng  Zhou  Xiaosi 《中国科学:化学(英文版)》2022,65(9):1807-1816
Science China Chemistry - Due to their enormous potential for large-scale energy storage, rechargeable potassium-ion batteries have been widely researched and developed. However, the drastic volume...  相似文献   
106.
The N–N bond is present in many important organic compounds, such as hydrazines, pyrazoles, azos, etc. Many methods based on transition metal catalyzed N–N coupling or functionalization of hydrazine have been reported for the synthesis of N–N containing organic compounds. In recent years, electrochemical dehydrogenative N–H/N–H coupling has become a powerful tool for the construction of N–N bearing organic compounds. The electrochemical methods employ electrons as traceless redox reagents instead of chemicals and produce hydrogen as the only byproduct. In this review, we summarize the recent advances in the electrochemical dehydrogenative N–H/N–H coupling reactions with focus on the mechanistic insights and synthetic applications of these transformations.  相似文献   
107.
Li  Zh.  Zhang  Y.  Wang  R.  Jiang  D. 《Journal of Applied Spectroscopy》2022,89(2):371-380
Journal of Applied Spectroscopy - The concentration of heavy metals in drinking water is an important standard for water quality evaluation and water pipeline corrosion detection. This research...  相似文献   
108.
Acta Mathematica Sinica, English Series - We are interested in the existence and asymptotic behavior for the least energy solutions of the following fractional eigenvalue problem $$\left({\rm{P}}...  相似文献   
109.
Chen  Renhong  Mei  Jie  Xu  Jin  Xu  Wanjie  Wang  Laisen  Chen  Yuanzhi  Peng  Dong-Liang 《Journal of Solid State Electrochemistry》2022,26(6):1359-1368
Journal of Solid State Electrochemistry - High-voltage LiNi0.5Mn1.5O4 with a spinel structure is considered as important cathode materials for high-energy density Li-ion batteries (LIBs). In this...  相似文献   
110.
Let L be an additive map between (real or complex) matrix algebras sending n×n Hermitian idempotent matrices to m×m Hermitian idempotent matrices. We show that there are nonnegative integers p,q with n(p+q)=rm and an m×m unitary matrix U such thatL(A)=U[(Ip?A)(Iq?At)0m?r]U?,for any n×n Hermitian A with rational trace. We also extend this result to the (complex) von Neumann algebra setting, and provide a supplement to the Dye-Bunce-Wright Theorem asserting that every additive map of Hermitian idempotents extends to a Jordan ?-homomorphism.  相似文献   
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