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排序方式: 共有419条查询结果,搜索用时 31 毫秒
331.
An amperometric mediated glucose biosensor has been developed based on a sol–gel derived carbon composite material. Glucose oxidase and the mediator vinylferrocene have been immobilised within the porous, rigid and organically modified silicate network in the composite material. The organic group in the silicate network controls the hydrophobicity of the electrode surface and thus limits the wettability of the electrode surface. Various important fabrication factors controlling the biosensor performance have been investigated systematically. The glucose biosensor can be renewed easily in a reproducible manner by a simple polishing step and it has a long operational lifetime. Applicability of the biosensor has been demonstrated in real samples and the results obtained by this biosensor corroborate well with a classical UV spectrophotometric technique. 相似文献
332.
Lian Ee Khoo Ngoh Khang Goh Lip lin Koh Yan Xu Deborah J Whalen George Eng 《应用有机金属化学》1996,10(6):459-465
Four triphenyltin carboxylates formulated as o- Ph3SnOCOC6H4CH=N–Ar (Ar=C6H5; p -CH3C6H4; o -CH3C6H4; o -HOC6H4) were prepared and spectroscopically characterized. The crystal structure of o -Ph3SnOCOC6 H4CH=NC6H5 indicates that the tin atom, in each of the two molecules comprising the asymmetric unit, exists in a distorted tetrahedral geometry owing to an intramolecular acyl O. . .Sn contact. These new triphenyltin carboxylates display marked toxicity against the fungus Ceratocystis ulmi . 相似文献
333.
Lin Cheng Kun Wang Jianyong Mao Xiao Ming Goh Zhiqin Chu Yanpeng Zhang Lei Zhang 《Annalen der Physik》2019,531(9)
Subwavelength structures can provide a versatile platform for displaying various colors. Here, a reflection‐type approach to structural colors enabled by an extrinsic polarization‐dependent plasmonic resonance using aluminum nanohole arrays is presented theoretically. Usually, nanohole arrays with small hole sizes support whitish structural colors due to the narrow‐band reflection dip and high‐reflection nonresonant background. Interestingly, the lineshape of the resonance can be converted from a reflection dip with a high background to a reflection peak with negligible background using a pair of linear polarizers to select the polarization states of the incident light and the detected signal. Therefore, the resultant colors can be switched between whitish colors and vibrant colors, which are covert and overt under a white lighting condition, respectively. Due to the huge contrast between the two types of colors, this approach provides a novel scheme for the development of security‐related color labels. 相似文献
334.
Faiza Naureen Yasar Shah Sayyed Ibrahim Shah Muhammad Abbas Inayat Ur Rehman Salar Muhammad Hamdullah Khang Wen Goh Fazli Khuda Amjad Khan Siok Yee Chan Mehwish Mushtaq Long Chiau Ming 《Molecules (Basel, Switzerland)》2022,27(13)
Mirtazapine is a tetracyclic anti-depressant with poor water solubility. The aim of this study was to improve the dissolution rate of mirtazapine by delivering the drug as a liquisolid compact. Central composite design (CCD) was employed for the preparation of mirtazapine liquisolid compacts. In this, the impacts of two independent factors, i.e., excipient ratio (carrier:coating) and different drug concentration on the response of liquisolid system were optimized. Liquisolid compacts were prepared using propylene glycol as a solvent, microcrystalline cellulose as a carrier, and silicon dioxide (Aerosil) as the coating material. The crystallinity of the formulated drug and the interactions between the excipients were examined using X-ray powder diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR), respectively. The dissolution study for the liquisolid compact was carried out as per FDA guidelines. The results showed loss of crystallinity of the mirtazapine in the formulation and was completely solubilized in non-volatile solvent and equally dispersed throughout the powder system. Moreover, drug dissolution was found to be higher in liquisolid compacts than the direct compressed conventional tablets (of mirtazapine). The liquisolid technique appears to be a promising approach for improving the dissolution of poorly soluble drugs like mirtazapine. 相似文献
335.
Said Moshawih Rabiatul Nur Amalia Abdullah Juperi Ganesh Sritheran Paneerselvam Long Chiau Ming Kai Bin Liew Bey Hing Goh Yaser Mohammed Al-Worafi Chee-Yan Choo Shobna Thuraisingam Hui Poh Goh Nurolaini Kifli 《Molecules (Basel, Switzerland)》2022,27(6)
Common wheat (Triticum aestivum), one of the world’s most consumed cereal grains, is known for its uses in baking and cooking in addition to its medicinal uses. As this plant’s medical benefits are enormous and scattered, this narrative review was aimed at describing the pharmacological activities, phytochemistry, and the nutritional values of Triticum aestivum. It is a good source of dietary fiber, resistant starch, phenolic acids, alkylresorcinols, lignans, and diverse antioxidant compounds such as carotenoids, tocopherols and tocotrienols. These constituents provide Triticum aestivum with a wide range of pharmacological properties, including anticancer, antimicrobial, antidiabetic, hypolipemic, antioxidant, laxative, and moisturizing effects. This review summarized the established benefits of wheat in human health, the mode of action, and different clinical, in vitro and in vivo studies for different varieties and cultivars. This review also gives an insight for future research into the better use of this plant as a functional food. More clinical trials, in vivo and in vitro studies are warranted to broaden the knowledge about the effect of Triticum aestivum on nutrition-related diseases prevention, and physical and mental well-being sustenance. 相似文献
336.
AbstractRecently, research on solid polymer electrolytes (SPEs) for lithium-ion batteries (LIBs) has been actively carried out as an alternative to conventional liquid electrolytes that present safety issues such as flammability and explosion. However, the SPEs show relatively low ion conductivity, compared to the liquid electrolytes. In this study, a poly(vinylidene difluoride) (PVDF)-based SPE was prepared by introducing two different electrolytes; one is weak-binding lithium bis(trifluoromethane)sulfonimide (LiTFSI) salt mixture with solvating plastic crystal succinonitrile (SN) and the other is lithium bis(fluorosulfonyl)imide (LiFSI) salts. Among the SPEs studied, the PVDF/LiFSI-containing SPE membrane exhibited the highest room temperature ion conductivity of 1 x 10?3 S/cm, characterized by electrochemical impedance spectroscopy (EIS). 相似文献
337.
338.
Jia Ling Tsong Lucky Poh Wah Goh Jualang Azlan Gansau Siew-Eng How 《Molecules (Basel, Switzerland)》2021,26(22)
Nephelium lappaceum (N. lappaceum) and Nephelium ramboutan-ake (N. ramboutan-ake) are tropical fruits that gain popularity worldwide due to their tastiness. Currently, their potential to be used as pharmaceutical agents is underestimated. Chronic diseases such as cancer, diabetes and aging have high incidence rates in the modern world. Furthermore, pharmaceutical agents targeting pathogenic microorganisms have been hampered by the growing of antimicrobial resistance threats. The idea of food therapy leads to extensive nutraceuticals research on the potential of exotic fruits such as N. lappaceum and N. ramboutan-ake to act as supplements. Phytochemicals such as phenolic compounds that present in the fruit act as potent antioxidants that contribute to the protective effects against diseases induced by oxidative stress. Fruit residuals such as the peel and seeds hold greater nutraceutical potential than the edible part. This review highlights the antioxidant and biological activities (anti-neoplastic, anti-microbial, hypoglycemic actions and anti-aging), and chemical contents of different parts of N. lappaceum and N. ramboutan-ake. These fruits contain a diverse and important chemical profile that can alleviate or cure diseases. 相似文献
339.
Synthesis and characterization of high refractive index polyimides derived from 2,5‐Bis(4‐Aminophenylenesulfanyl)‐3,4‐Ethylenedithiothiophene and aromatic dianhydrides
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Hyeonuk Yeo Jiye Lee Munju Goh Bon‐Cheol Ku Honglae Sohn Mitsuru Ueda Nam‐Ho You 《Journal of polymer science. Part A, Polymer chemistry》2015,53(7):944-950
The authors describe the synthesis and characterization of the polyimide (PI) series containing a 2,5‐bis(4‐aminophenylenesulfanyl)‐3,4‐ethylenedithiothiophene (APSEDTT) moiety in their main chain. The APSEDTT monomer with high sulfur content was prepared and polymerized with several aromatic dianhydrides such as 4,4′‐[p‐thio bis(phenylenesulfanyl)]diphthalic anhydride (3SDEA), 4,4′‐biphthalic anhydride (BPDA), and 4,4′‐oxydiphthalic anhydride (ODPA) by the traditional two‐step polycondensation procedure. All PIs exhibited high transparency, higher than 75% at 550 nm for a thickness of about 20 μm and good thermal properties such as thermal decomposition temperatures (T10%) in the range of 409–521 °C. In addition, the PIs have extraordinarily excellent optical properties in refractive index and birefringence as originally designed. In particular, the PI derived from APSEDTT and 3SDEA showed a high refractive index (1.7586), and a low birefringence (0.0087) because of their very high sulfur content (27.7%). © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 944–950 相似文献
340.
Ranya Simons Stefanie Nina Guntari Tor Kit Goh Greg G. Qiao Stuart A. Bateman 《Journal of polymer science. Part A, Polymer chemistry》2012,50(1):89-97
Exfoliated poly(dicyclopentadiene) (pDCPD)—montmorillonite (MMT) nanocomposites were synthesized via intergallery‐surface‐initiated ring opening metathesis polymerization (ROMP). This is the first example of in situ polymerization of pDCPD from clay intergallery surfaces using ROMP. Grubbs catalyst was immobilized on the surface of MMT clay modified with vinylbenzyl dimethyloctadecyl ammonium chloride (VOAC), and DCPD polymerized from the clay surface while simultaneously crosslinking to form a thermoset nanocomposite in a one‐pot reaction. X‐ray diffraction and transmission electron microscopy analysis indicated that the resultant nanocomposites exhibited exfoliated morphologies with heterogeneous clay platelet distribution. Conventional bulk‐initiated nanocomposites containing VOAC modified MMT were also synthesized as a comparison, and these resulted in nanocomposites with intercalated morphologies. The differences between the morphologies demonstrated that growing polymer chains from the initiator sites on the intergallery surface of the clay platelets pushed the platelets apart during the polymerization of the intergallery‐surface‐initiated nanocomposites, aiding in the exfoliation process. Compression testing indicated that the intergallery‐surface‐initiated nanocomposites led to improvements of up to 50% in the compressive Young's Modulus, while the bulk‐initiated nanocomposites at the same clay loadings did not exhibit improved properties. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献