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11.
Measurement of small-signal and large-signal responses of packaged laser modules at high temperature
Ning Hua Zhu Ji Min Wen Hai Peng Song Shang Jian Zhang Liang Xie 《Optical and Quantum Electronics》2006,38(15):1245-1257
In this paper, the pulsed injection method is extended to measure the chip temperature of various packaged laser modules,
such as the DFB laser modules, the FP laser modules, and the EML laser modules. An optimal injection condition is obtained
by investigating the dependence of the lasing wavelength on the width and period of the injection pulse in a relatively wide
temperature range. The small-signal frequency responses and large-signal performances of packaged laser modules at different
chip temperature are measured. The adiabatic small-signal modulation characteristics of packaged LD are first extracted. In
the large-signal measurement, the effects of chip temperature, bias current and driving signal on the performances of the
laser modules are discussed. It has been found that the large-signal performances of the EML modules depend on the different
red-shift speeds of the DFB and EAM sections as chip temperature varying, and the optimal characteristics may be achieved
at higher temperature. 相似文献
12.
13.
以2-(3,4-环己基类二氧-5-异丙基)苯基乙醇(2)和3-异丙氧基-5,5-二甲基-1,3-环己烯酮(4)为原料,利用羰基α-位的烷基化反应和分子内的Friedel-Carfts反应为关键步骤,经9步反应,合成了多氧芳香型三环二萜类天然产物Salvinolone。 相似文献
14.
15.
Jun Fan Wei‐Guang Zhang Min‐Yu Tan Yu Tang Wei‐Sheng Liu Ning Tang Kai‐Bei Yu 《中国化学》2004,22(6):508-511
The La(III) complex with a new amide‐type tripodal ligand,2,2′.2″‐nitrilotris{[(2′‐benzylaminofomyl)‐phenoxylethyl)amine (L), was synthesized and characterized by X‐ray crystallographic analysis. Crystal data: C48H55.50LaN7O18.75, Mr=1169.40, monoclinic. space group, P21/n, a= 1.0644(3) nm. b=2.3889(5) nm, c= 2.1917(5) nm, β=90.65°, V=5.573(2) nm3, Z=1, Dc=1.394 g°cm?3, R1=0.0487, wR [1>2s?(I)]=0.1266. The results reveal that each La(III) ion binds to 9 oxygen atoms, three of which belong to carbonyl groups from three tripodal ligands and six to three bidentate nitrate groups and a two‐dimensional sheet of 4.82 networks is assembled by metal‐ligand coordination interaction. L, a heptadentate compound, merely acts as a tridentate bridging spacer due to its steric hindrance and links the La(III) ions as three‐connected nodes. 相似文献
16.
Zhang YL Qin WW Liu WS Tan MY Tang N 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(10):2153-2157
An amide-based open-chain crown ether ligand and its complexes with europium and terbium were synthesized. The complexes were characterized by elemental analysis, infrared spectra and conductivity. The europium and terbium ions were found to coordinate to the C=O oxygen atoms and pyridine nitrogen atoms. The fluorescence properties of these complexes in DMF and CH3OH/CHCl3 were studied. Under the excitation of UV light, these complexes exhibit characteristic fluorescence of europium and terbium ions. The solvent factors influencing the fluorescent intensity are discussed. 相似文献
17.
Ning Li Chunhui Deng Ning Yao Xizhong Shen Xiangmin Zhang 《Analytica chimica acta》2005,540(2):317-323
In the study, we developed a simple, rapid, sensitive, and inexpensive method for determination of the disease biomarkers of acetone, hexanal and heptanal in human blood. For the first time, derivatization of carbonyls with O-2,3,4,5,6-(pentafluorobenzyl)hydroxylamine (PFBHA) was combined with headspace single-drop microextractin (HS-SDME) and gas chromatography-mass spectrometry (GC–MS) and applied to the analysis of acetone, hexanal, and heptanal in human blood. At first, acetone, hexanal and heptanal in blood were derivatized with PFBHA and formed oximes in several seconds. Sequentially, the oximes were headspace extracted and concentrated by a microdrop solvent. Finally, the extracted oximes were analyzed by GC–MS. HS-SDME conditions and method validations were studied. Due to needing of only 2 μl organic solvent, short extraction time of 8 min, and simple operation, derivatization-HS-SDME was shown to be a rapid, simple, and inexpensive technique for analysis of acetone, hexanal, and heptanal in human blood. Moreover, it had low detection limit values from 0.24 to 0.62 nM, and good reproducibility (R.S.D. less than 12%). 相似文献
18.
Ning Luo J. Brian Hutchison Kristi S. Anseth Christopher N. Bowman 《Journal of polymer science. Part A, Polymer chemistry》2002,40(11):1885-1891
(Methacryloyl ethylenedioxycarbonyl) benzyl N,N‐diethyldithiocarbamate (HEMA‐E‐In) was synthesized and used as a monomer iniferter to develop a novel, photopatternable grafting technology. This molecule functions as both a methacrylic monomer and a photoiniferter (photoinitiator–transfer agent–terminator). The structure of HEMA‐E‐In was characterized by 1H NMR, Fourier transform infrared, and ultraviolet–visible spectroscopies. In the presence of the monomer iniferter, methyl methacrylate was polymerized by exposure to 365‐nm ultraviolet radiation, confirming the initiation capability of HEMA‐E‐In. After the copolymerization of HEMA‐E‐In into a methacrylate‐based polymer, attenuated total reflectance Fourier transform infrared spectra revealed that the photoiniferter functionality was present at the surface of this polymeric substrate. Photografting of poly(ethylene glycol) monomethacrylate monomer from the surface caused a significant change in the hydrophobicity of the surface as demonstrated by contact angle measurements. The novel monomer photoiniferter HEMA‐E‐In initiates the polymerization of bulk monomer and provides a reactive functionality that facilitates further initiation and polymer modification by the polymerization of different monomers. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1885–1891, 2002 相似文献
19.
WU Yan-Qi LOU Ning LI Yu 《有机化学》2003,23(Z1):442-442
From the ethanolic extract of the whole plant of Anaphalis aureo-punctata, a new acylated flavonoid glycoside 3-O-kaempferol-3-O-acetyl-6-O-(p-coumaroyl)-β-D-glucopyranoside (1), and five known phenolic compounds 3-O-kaempferol-6- O- ( p-coumaroyl )-β-D-glucopyranoside ( 2 ), kaempferol-3- O-β-D-glucopyranoside 3,6-(4′-hydroxystyryl)-4-methoxy-2-pyrone (4), 2H-pyran-2-one, 6-[ 2-( 4-(β-D-glucopyranosyloxy ) phenyl ) ethenyl ]-4-methoxy-( E ) (5) and 4-hydroxy-3-methoxycinnamic hexacosyl ester (6) were isolated. Their structures were established by spectral methods (UV, IR, MS, 1D, 2D-NMR). The flavonoid glycosides, 1, 2 and 3 showed markedly inhibited oxidative DNA strand breaks induced by Fenton reaction and NADH/PMS in a concentration-dependent manner. 相似文献
20.