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61.
Samsuri  S. A. M.  Rahman  M. Y. A.  Umar  A. A.  Salleh  M. M. 《Ionics》2017,23(12):3533-3544
Ionics - TiO2 nanoflower (NF)-ZnO composite films were synthesized by using liquid phase deposition (LPD) and dip coating method. At the lower growth temperature below 50 °C, the...  相似文献   
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This work reports the effectiveness of short polar peptides as asymmetric catalysts in Michael reactions to attain good yields of enantio- and diastereoselective isomers. In a comparison, glutamic acid and histidine produced greater ee and yields when they were applied as the second amino acid in short trimeric peptides. These short polar peptides were found to be efficient organocatalysts for the asymmetric Michael addition reaction in water.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.  相似文献   

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In Southeast Asia, traditional medicine has a longestablished history and plays an important role in the health care system. Various traditional medicinal plants have been used to treat diseases since ancient times and much of this traditional knowledge remains preserved today. Oroxylum indicum (beko plant) is one of the medicinal herb plants that is widely distributed throughout Asia. It is a versatile plant and almost every part of the plant is reported to possess a wide range of pharmacological activities. Many of the important bioactivities of this medicinal plant is related to the most abundant bioactive constituent found in this plant—the baicalein. Nonetheless, there is still no systematic review to report and vindicate the biological activities and therapeutic potential of baicalein extracted from O. indicum to treat human diseases. In this review, we aimed to systematically present in vivo and in vitro studies searched from PubMed, ScienceDirect, Scopus and Google Scholar database up to 31 March 2020 based on keywords “Oroxylum indicum” and “baicalein”. After an initial screening of titles and abstracts, followed by a full-text analysis and validation, 20 articles that fulfilled all the inclusion and exclusion criteria were included in this systematic review. The searched data comprehensively reported the biological activities and therapeutic potential of baicalein originating from the O. indicum plant for anti-cancer, antibacterial, anti-hyperglycemia, neurogenesis, cardioprotective, anti-adipogenesis, anti-inflammatory and wound healing effects. Nonetheless, we noticed that there was a scarcity of evidence on the efficacy of this natural active compound in human clinical studies. In conclusion, this systematic review article provides new insight into O. indicum and its active constituent baicalein as a prospective complementary therapy from the perspective of modern and scientific aspect. We indicate the potential of this natural product to be developed into more conscientious and judicious evidencebased medicine in the future. However, we also recommend more clinical research to confirm the efficacy and safety of baicalein as therapeutic medicine for patients.  相似文献   
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The photovoltaic characteristics of a photoelectrochemical cell of ITO/TiO2/PVC-LiClO4/graphite are reported. This paper is concerned with the influence of light intensity and temperature on short-circuit current density, Jsc and open-circuit voltage, Voc of the device. The photoelectrochemical cell material was a screen-printed layer of titanium dioxide onto an ITO-covered glass substrate, which was used as a working electrode of the cell. The solid electrolyte was polivinylchloride-lithium perchlorate. The graphite film serves as a counter electrode of the cell. The current density–voltage characteristics of the device under an illumination of 20, 40, 60, 80 and 100 mW cm−2 light from a tungsten halogen lamp were recorded at 40 °C as well as under an illumination of 100 mW cm−2 at 30, 35, 40, 45 and 50 °C, respectively. It was found that the short-circuit current density, Jsc of the device increases with both light intensity and temperature. The Jsc obtained at 100 mW cm−2 was 1.0 μAcm−2 and that at 50 °C was 0.7 μAcm−2.  相似文献   
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For studying nanoglobular modification effects in radiation cured polymeric composites, we prepared polymerization active silico-organic nanoparticles. With their polymerization active ligands, these nanoparticles form crosslinks by modifying the viscoelastic properties in radiation cured polymeric nanocomposites. In this process, there was a polymerization activity imparted to the particle surfaces of nanopowders, thus applying the physico-chemical modification scheme of a heterogeneous copolymerization to novel scratch and abrasion resistant coatings. By varying the nanoparticle-monomer formulation and the curing method, additional property can be achieved. In this works, we also investigated the influence of various factors such as addition of photoinitiators and other additives into the formulations. The coating materials were applied to the substrate by using different type of coaters. These materials were cured by ultraviolet light and electron beam irradiation. Properties of coatings were characterized using Universal scratch tester and Taber abrasion tester.  相似文献   
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An electrochemical DNA biosensor was developed that is based on a gold electrode modified with a nanocomposite membrane made from an ionic liquid, ZnO nanoparticles and chitosan. A single-stranded DNA probe was immobilized on this electrode. Acridine orange was used as the hybridization probe for monitoring the hybridization of the target DNA. The biosensor was capable of detecting target DNA in the concentration range from 1.0?×?10?C14 to 1.8?×?10?C4?mol?L-1, with a detection limit of 1.0?×?10?C15?mol?L-1. The approach towards constructing a DNA biosensor allows studies on the hybridization even with crude DNA fragments and also to analyze sample obtained from real samples. The results show that the DNA biosensor has the potential for sensitive detection of a specific sequence of the Trichoderma harzianum gene and provides a quick, sensitive and convenient method for the study of microorganisms.
Figure
Suggested interaction mechanism of modified electrode (IL/ZnO/CHIT/AuE) between immobilization and hybridization  相似文献   
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In this letter, we propose a new architecture of Time Wavelength Division Multiplexing Passive Optical Network (TWDM PON) system to support dynamic multi wavelength allocation (DMWA) in both upstream and downstream directions using an integrated semiconductor optical amplifier (SOA) and arrayed waveguide grating (AWG) with multi wavelength select continuous wave (CW) pump probe signal module. The significance of this architecture is the flexible routing function with the capability of multicasting and broadcasting between multiple optical line terminal (OLT) PON port with multiple optical distribution network (ODN) link using a new wavelength tuning free (WTF) OLT transmitter module to eliminate wavelength tuning delay in downstream signal utilizing multicasting Cross Gain Modulation (XGM) wavelength conversion. The experimental results show that 4λ × 10-Gb/s TWDM PON system can be used to connect 4096 users with the conventional fixed wavelength OLT transceivers with 36 dB link loss.  相似文献   
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