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171.
Kee CH Ariffin A Awang K Noorbatcha I Takeya K Morita H Lim CG Thomas NF 《Molecules (Basel, Switzerland)》2011,16(9):7267-7287
The n-butyramido, isobutyramido, benzamido, and furancarboxamido functions profoundly modulate the electronics of the stilbene olefinic and NH groups and the corresponding radical cations in ways that influence the efficiency of the cyclization due presumably to conformational and stereoelectronic factors. For example, isobutyramido- stilbene undergoes FeCl(3) promoted cyclization to produce only indoline, while n-butyramidostilbene, under the same conditions, produces both indoline and bisindoline. 相似文献
172.
Qureshi AK Mukhtar MR Hirasawa Y Hosoya T Nugroho AE Morita H Shirota O Mohamad K Hadi AH Litaudon M Awang K 《Chemical & pharmaceutical bulletin》2011,59(2):291-293
Two new indole alkaloids, neolamarckines A and B (1, 2) were isolated from the leaves of Neolamarckia cadamba (Rubiaceae). Structural elucidation of 1 and 2 was performed by combination of 2D-NMR and circular dichroism (CD) spectra, and chemical correlations. Neolamarckine A (1) showed inhibition of inducible nitric oxide synthase (iNOS) dose dependently. 相似文献
173.
In this paper, we investigate the local existence and the finite‐time blow‐up of solutions for a semi‐linear parabolic system with a nonlinear memory. Moreover, we give the blow‐up rate of solutions and the necessary conditions for local or global existence. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
174.
175.
Intensity modulated fiber vibrations sensing using Khazani Syed (KS) and Modified Quadratic Congruence Code (MQC) code for quasi distributed vibration measurement have been evaluated. The systems employed Spectral Direct (SD) Decoding for Spectral Amplitude Coding-Optical Code Division Multiple Access (SAC-OCDMA). SAC-OCDMA is adopted because of its enormous impact in dealing with Multiple Access Interference (MAI). The setup was carried out for three sensor points in three consecutive measurements. The performance of the sensing system with the KS and MQC codes were compared at the same weight and number of code sequence. It was observed that the applied vibration frequencies were obtained at the receivers and the signal employing MQC are received at slightly better power than KS code. However, KS code setup employed less number of components and therefore, reduce the cost and complexity of achieving quasi-distributed vibration sensing. 相似文献
176.
Zahraoui Mehdi Mokhtar Adel Adjdir Mehdi Bennabi Farid Khaled Rahmani Djelad Amal Bengueddach Abdelkader Sassi Mohamed 《Research on Chemical Intermediates》2019,45(2):633-644
Research on Chemical Intermediates - In this work, the Al-magadiite is synthesized by the hydrothermal method. It is then used to prepare three copper exchanged materials using copper nitrate,... 相似文献
177.
178.
A multiwavelength Brillouin/erbium fiber laser (BEFL) with low threshold power is realized. A low threshold power of 3 mW and a wide tuning range of 18 nm can be achieved by controlling the reflected power in the nonlinear optical loop mirror (NOLM). Up to 24 lines with a wavelength spacing of 0.086 nm are generated at the Brillouin pump and at the 1 480-nm pump with 0.5 dBm (0.9 mW) and 25 mW of power, respectively. 相似文献
179.
Adel Mokhtar Zohra Aouali Kebir Medjhouda Amal Djelad Abdelkader Boudia Abdelkader Bengueddach Mohamed Sassi 《Chemical Papers》2018,72(1):39-50
In this work, the ion-exchange reaction of the sodium silicate Na-magadiite with cupric ions was studied and the mode of interaction of the intercalated Cu2+ ions with silicate sheet was investigated. To do this, Na-magadiite was first synthesized using a hydrothermal method and characterized. It is then used to prepare Cu-exchanged magadiite materials with different copper contents by an ion-exchange reaction. The solids obtained were characterized by chemical and thermogravimetric analyses, powder X-ray diffraction, UV–Visible diffuse reflectance and Fourier transform spectroscopy, scanning electron microscopy and transmission electron microscopy. The results show that magadiite has a high affinity to copper ions and that the experimental exchange rate can be easily predicted. They show also that the intercalated Cu2+ ions are non-hydrated and are in direct interactions with the terminal interlayer ≡Si–O? groups, to which they are also probably strongly linked. Furthermore, the interlayer copper oxide species phase formed are in form of small particles homogeneously dispersed. Finally, the introduction of Cu2+ ions into the interlayer space does not substantially affect the structure of the Cu-exchanged materials but rather tends to stabilize it by increasing the decomposition temperature of the silanol groups . 相似文献
180.
Ghafour Amouzad Mahdiraji Mohamad Khazani Abdullah Makhfudzah Mokhtar Amin Malekmohammadi Ahmad Fauzi Abas 《Optical Review》2009,16(4):422-425
An improved estimation of bit-error-rate (BER) for electrically multiplexed duty-cycle division multiplexing (E-DCDM), which
is based on the probability of error, is presented. Performance of 3 × 10 Gbit/s E-DCDM is investigated in terms of optical
signal-to-noise ratio (OSNR) and dispersion tolerance. This technique requires 29.4 dB OSNR and can tolerate ±96 ps/nm chromatic
dispersion for the worst user. 相似文献