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51.
Propagation of phase-locked partially coherent flattened beam array in turbulent atmosphere 总被引:2,自引:0,他引:2
Analytical formulae for phase-locked partially coherent flattened beam array propagating in a turbulent atmosphere are derived based on the extended Huygens–Fresnel principle. Beam propagation factor (BPF) is introduced to evaluate the beam quality at the receiving plane. The influence of beam order, transverse coherence width length and the intensity of turbulence is discussed in detail. 相似文献
52.
Laburnine’s dissolution behaviors in glucose and saline solution were studied by a micro-calorimetry method. The measured
integral and differential heats of solution were utilized to build equations of the solute and the heat, so that dissolution
thermodynamic equations and half-time periods, Δsol
H
m, Δsol
G
m, and Δsol
S
m were obtained. The results show that this study does not only provide a simple method for the determination of the half-life
period for a drug but also offer a theoretical reference for the clinical application of laburnine. 相似文献
53.
Two new guaianolide-type sesquiterpenoids,4β,9β-dihydroxy-1α,5α-H-guaia-6,10(14)-dien(1) and 4β,9β,10α-trihydroxy-1α,5α-H-guaia-6-en(2),along with four known sesquiterpenoids(3a,3b,4 and 5),were isolated from Kadsura interior.Their structures and configurations were elucidated by spectroscopic methods including 2D-NMR and HR-MS techniques.Compounds 3a and 3b were obtained as a pair of enantiomers,and their structure and absolute configuration were established from their extensive NMR spectra and by single-crystal X-ray analysis. 相似文献
54.
Attapulgite grafted with polystyrene via a simultaneous reverse and normal initiation atom transfer radical polymerization
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Haicun Yang Hongting Pu Fanghong Gong 《Journal of polymer science. Part A, Polymer chemistry》2016,54(11):1508-1516
The surface grafting of attapulgite (ATP) with polystyrene (PS) was established via a simultaneous reverse and normal initiation atom transfer radical polymerization (SR&NIATRP). 4‐(chloromethyl)phenyltrimethoxysilane (CMPTMS) chemical bounded on the surface of ATP (ATP‐Cl, Cl‐I) was prepared via one‐step self‐assembly. SR&NI ATRP of styrene was conducted using CuCl2 complex tris(2‐(dimethylamino)ethyl)amine (Me6‐TREN) as the catalytic system, initiated by 2,2‐azobis(isobutyronitrile) (AIBN) and ATP‐Cl. FT‐IR, XRD, XPS, TGA and TEM data were consistent with the grafting of benzyl chloride groups and PS chains on ATP surface. The controllability of polymerization was investigated by the kinetics behavior under different molar ratio of AIBN and CuCl2. The obtained polymer possessed a uniform distribution of molecular weights with a lower polydispersity index of 1.2~1.4. The relationship between polymerization on the surface of ATP and in solution was discussed in detail based on TGA data of hybrid particles and GPC trace of free polymer in solution. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1508–1516 相似文献
55.
Condruz Mihaela Raluca Matache Gheorghe Paraschiv Alexandru Pușcașu Cristian 《Journal of Thermal Analysis and Calorimetry》2018,133(1):443-452
Journal of Thermal Analysis and Calorimetry - Two new zinc(II) coordination compounds have been synthesized by the reaction of diazine-ring containing Schiff bases di(2-pyridyl) ketone... 相似文献
56.
Simulation of near-infrared photodiode detectors based on β-FeSi_2/4H-SiC heterojunctions 总被引:1,自引:0,他引:1
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In this paper,we propose a near-infrared p-type β-FeSi2/n-type 4H-SiC heterojunction photodetector with semiconducting silicide(β-FeSi2) as the active region for the first time.The optoelectronic characteristics of the photodetector are simulated using a commercial simulator at room temperature.The results show that the photodetector has a good rectifying character and a good response to near-infrared light.Interface states should be minimized to obtain a lower reverse leakage current.The response spectrum of the β-FeSi2/4H-SiC detector,which consists of a p-type β-FeSi2 absorption layer with a doping concentration of 1×1015cm-3 and a thickness of 2.5 μm,has a peak of 755 mA/W at 1.42 μm.The illumination of the SiC side obtains a higher responsivity than that of the β-FeSi2 side.The results illustrate that the β-FeSi2/4H-SiC heterojunction can be used as a near-infrared photodetector compatible with near-infrared optically-activated SiC-based power switching devices. 相似文献
57.
In this paper, we study the system of strong vector quasi-equilibrium problems without assuming that the dual of the ordering cone has a weak* compact base. We show the existence and essential components of solution set for system of strong vector quasi-equilibrium problems by defining the best-reply mapping. 相似文献
58.
Prof. Hisahiro Sasabe Prof. Yuki Kato Dr. Yuichiro Watanabe Tatsuya Ohsawa Dr. Naoya Aizawa Prof. Wataru Fujiwara Dr. Yong-Jin Pu Prof. Hiroshi Katagiri Prof. Junji Kido 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(71):16294-16300
Exploration of pure metal-free organic molecules that exhibit strong room-temperature phosphorescence (RTP) is an emerging research topic. In this regard, unveiling the design principles for an efficient RTP molecule is an essential, but challenging, task. A small molecule is an ideal platform to precisely understand the fundamental role of each functional component because the parent molecule can be easily derivatized. Here, the RTP behaviors of a series of 3-pyridylcarbazole derivatives are presented. Experimental studies in combination with theoretical calculations reveal the crucial role of the n orbital on the central pyridine ring in the dramatic enhancement of the intersystem crossing between the charge-transfer-excited singlet state and the locally excited triplet states. Single-crystal X-ray crystallographic studies apparently indicate that both the pyridine ring and fluorine atom contribute to the enhancement of the RTP because of the restricted motion owing to weak C−H⋅⋅⋅N and H⋅⋅⋅F hydrogen-bonding interactions. The single crystal of the fluorine-substituted derivative shows an ultra-long phosphorescent lifetime (τP) of 1.1 s and a phosphorescence quantum yield (ΦP) of 1.2 %, whereas the bromine-substituted derivative exhibits τP of 0.15 s with a ΦP of 7.9 %. We believe that this work provides a fundamental and universal guideline for the generation of pure organic molecules exhibiting strong RTP. 相似文献
59.
60.
Inorganic polyhedral oligomeric silsesquioxane (POSS) was used as the core for the synthesis of poly(Llysine) peptide dendrimer via copper-catalyzed azide-alkyne click chemistry. The inorganic/organic composite dendrimer was characterized by MS, 1H NMR, FTIR, GPC and DLS. 相似文献