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341.
342.
Y. Wang S. W. Liu X. W. Sun J. L. Zhao G. K. L. Goh Q. V. Vu H. Y. Yu 《Journal of Sol-Gel Science and Technology》2010,55(3):322-327
Highly transparent In-Ga-Zn oxide (IGZO) thin films were fabricated by spin coating using acetate- and chlorate-based precursors,
and thin film transistors (TFTs) were further fabricated employing these IGZO films as the active channel layer. The impact
of the post-annealing temperature on the physical properties of IGZO films and performance of IGZO TFTs were investigated.
Compared to the nitrate-based IGZO precursor, the chlorate-based precursor increases the phase change temperature of IGZO
thin films. The IGZO films changed from amorphous to nanocrystalline phase in an annealing temperature range of 600–700 °C.
The transparency is more than 90% in the visible region for IGZO films annealed with temperatures higher than 600 °C. With
the increase of post-annealing temperature, the carrier concentration of IGZO film decreases, while the sheet resistance increases
firstly and then saturates. The bottom-gate TFT with IGZO channel annealed at 600 °C in oxygen showed the best performance,
which was operated in n-type enhancement mode with a field effect mobility of 1.30 cm2/V s, a threshold voltage of 10 V, and a drain current on/off ratio of 2.5 × 104. 相似文献
343.
Dr. Yong‐Qiang Li Bowen Zhu Dr. Yuangang Li Wan Ru Leow Rubayn Goh Dr. Bing Ma Prof. Eileen Fong Dr. Mark Tang Prof. Xiaodong Chen 《Angewandte Chemie (International ed. in English)》2014,53(23):5837-5841
Despite the advanced detection and sterilization techniques available today, the sensitive diagnosis and complete elimination of bacterial infections remain a significant challenge. A strategy is reported for efficient bacterial capture (ca. 90 %) based on the synergistic effect of the nanotopography and surface chemistry of the substrate on bacterial attachment and adhesion. The outstanding bacterial‐capture capability of the functionalized nanostructured substrate enables rapid and highly sensitive bacterial detection down to trace concentrations of pathogenic bacteria (10 colony‐forming units mL?1). In addition, this synergistic biocapture substrate can be used for efficient bacterial elimination and shows great potential for clinical antibacterial applications. 相似文献
344.
Ilhame Bourais Salma Elmarrkechy Douae Taha Bouabid Badaoui Yassine Mourabit Najoua Salhi Mohammed Merae Alshahrani Ahmed Abdullah Al Awadh Abdelhakim Bouyahya Khang Wen Goh Ching Siang Tan Souad El Hajjaji Nadia Dakka Naima Iba 《Molecules (Basel, Switzerland)》2022,27(24)
Leaves, husk, kernels, and bark methanolic extracts of Juglans regia L. were tested for their in vitro antidiabetic, anti-inflammatory, and antioxidant activities. For these purposes, α-amylase and α-glucosidase were used as the main enzymes to evaluate antidiabetic activities. Moreover, lipoxidase and tyrosinase activities were tested to estimate anti-inflammatory properties. Antioxidant properties of Juglans regia L., extracts were determined using three different assays. Leaves extract has an important radical scavenging activity and a-amylase inhibition. Similarly, husk extracts showed high total phenolic content (306.36 ± 4.74 mg gallic acid equivalent/g dry extract) with an important α-amylase inhibition (IC50 = 75.42 ± 0.99 µg/mL). Kernels exhibit significant tyrosinase (IC50 = 51.38 ± 0.81 µg/mL) correlated with antioxidant activities (p < 0.05). Husk and bark extracts also showed strong anti-lipoxidase activities with IC50 equal to 29.48 ± 0.28 and 28.58 ± 0.35 µg/mL, respectively. HPLC-DAD-ESI-MS/MS analysis highlights the phenolic profile of methanolic extracts of Juglans regia L. plant parts. The identified polyphenols were known for their antioxidant, antidiabetic (dicaffeoyl-quinic acid glycoside in kernels), and anti-inflammatory (3,4-dihydroxybenzoic acid in leaves) activities. Further investigations are needed to determine molecular mechanisms involved in these effects as well as to study the properties of the main identified compounds. 相似文献
345.
Youssef Elouafy Adil El Yadini Hamza El Moudden Hicham Harhar Mohammed Merae Alshahrani Ahmed Abdullah Al Awadh Khang Wen Goh Long Chiau Ming Abdelhakim Bouyahya Mohamed Tabyaoui 《Molecules (Basel, Switzerland)》2022,27(22)
The present study investigated and compared the quality and chemical composition of Moroccan walnut (Juglans regia L.) oil. This study used three extraction techniques: cold pressing (CP), soxhlet extraction (SE), and ultrasonic extraction (UE). The findings showed that soxhlet extraction gave a significantly higher oil yield compared to the other techniques used in this work (65.10% with p < 0.05), while cold pressing and ultrasonic extraction gave similar yields: 54.51% and 56.66%, respectively (p > 0.05). Chemical composition analysis was carried out by GC–MS and allowed 11 compounds to be identified, of which the major compound was linoleic acid (C18:2), with a similar percentage (between 57.08% and 57.84%) for the three extractions (p > 0.05). Regarding the carotenoid pigment, the extraction technique significantly affected its content (p < 0.05) with values between 10.11 mg/kg and 14.83 mg/kg. The chlorophyll pigment presented a similar content in both oils extracted by SE and UE (p > 0.05), 0.20 mg/kg and 0.16 mg/kg, respectively, while the lowest content was recorded in the cold-pressed oil with 0.13 mg/kg. Moreover, the analysis of phytosterols in walnut oil revealed significantly different contents (p < 0.05) for the three extraction techniques (between 1168.55 mg/kg and 1306.03 mg/kg). In addition, the analyses of tocopherol composition revealed that γ-tocopherol represented the main tocopherol isomer in all studied oils and the CP technique provided the highest content of total tocopherol with 857.65 mg/kg, followed by SE and UE with contents of 454.97 mg/kg and 146.31 mg/kg, respectively, which were significantly different (p < 0.05). This study presents essential information for producers of nutritional oils and, in particular, walnut oil; this information helps to select the appropriate method to produce walnut oil with the targeted quality properties and chemical compositions for the desired purpose. It also helps to form a scientific basis for further research on this plant in order to provide a vision for the possibility of exploiting these oils in the pharmaceutical, cosmetic, and food fields. 相似文献
346.
Yik-Ling Chew Mei-Ann Khor Zhao Xu Sue-Kei Lee Jing-Wen Keng Sze-Huey Sang Gabriel Akyirem Akowuah Khang Wen Goh Kai Bin Liew Long Chiau Ming 《Molecules (Basel, Switzerland)》2022,27(17)
Traditional medicine is critical in disease treatment and management. Herbs are gaining popularity for disease management and treatment. Therefore, they can be utilised as complementary and alternative treatment (CAT) ingredients. Atopic dermatitis (AD) is one of the common non-communicable diseases. It is characterised by chronic inflammatory skin disease with intense pruritus and eczematous lesions. AD is associated with oxidative stress, microbial infection, and upregulation of inflammatory cytokines. Both children and adults could be affected by this skin disorder. The prevalence of AD is increasing along with the country’s level of development. This review revisited the literature on four medicinal herbs widely used as complementary medicine to manage AD. These therapeutic herbs are commonly eaten as food and used as spices in Asian cuisine. The four food herbs reviewed are Cassia alata, Coriandrum sativum, Curcuma longa Linn, and Azadirachta indica. Their traditional uses and phytochemical content will be covered. Four relevant pharmacological and biological activities of the plants crucial in AD management have been reviewed and discussed, including anti-inflammatory, anti-microbial, antioxidant, and wound recovery. 相似文献
347.
Jagjit Singh Dhaliwal Said Moshawih Khang Wen Goh Mei Jun Loy Md. Sanower Hossain Andi Hermansyah Vijay Kotra Nurolaini Kifli Hui Poh Goh Sachinjeet Kaur Sodhi Dhaliwal Hayati Yassin Long Chiau Ming 《Molecules (Basel, Switzerland)》2022,27(20)
Chalcones have been well examined in the extant literature and demonstrated antibacterial, antifungal, anti-inflammatory, and anticancer properties. A detailed evaluation of the purported health benefits of chalcone and its derivatives, including molecular mechanisms of pharmacological activities, can be further explored. Therefore, this review aimed to describe the main characteristics of chalcone and its derivatives, including their method synthesis and pharmacotherapeutics applications with molecular mechanisms. The presence of the reactive α,β-unsaturated system in the chalcone’s rings showed different potential pharmacological properties, including inhibitory activity on enzymes, anticancer, anti-inflammatory, antibacterial, antifungal, antimalarial, antiprotozoal, and anti-filarial activity. Changing the structure by adding substituent groups to the aromatic ring can increase potency, reduce toxicity, and broaden pharmacological action. This report also summarized the potential health benefits of chalcone derivatives, particularly antimicrobial activity. We found that several chalcone compounds can inhibit diverse targets of antibiotic-resistance development pathways; therefore, they overcome resistance, and bacteria become susceptible to antibacterial compounds. A few chalcone compounds were more active than conventional antibiotics, like vancomycin and tetracycline. On another note, a series of pyran-fused chalcones and trichalcones can block the NF-B signaling complement system implicated in inflammation, and several compounds demonstrated more potent lipoxygenase inhibition than NSAIDs, such as indomethacin. This report integrated discussion from the domains of medicinal chemistry, organic synthesis, and diverse pharmacological applications, particularly for the development of new anti-infective agents that could be a useful reference for pharmaceutical scientists. 相似文献
348.
An efficient convergent strategy for the construction of a trans-fused 6-6-6-6-membered tetracyclic ether ring system was developed. The key steps involve coupling of two cyclic ethers by esterification, SmI2-promoted intramolecular reductive cyclization of iodo ester to hemiacetal, dehydration to dihydropyran, hydroboration, oxidation, intramolecular acetalization, and Lewis-acid catalyzed silane reduction. 相似文献
349.
Chang Xu Yongxin Li Lai Yoong Goh Sumod A. Pullarkat 《Journal of organometallic chemistry》2012,696(26):4207-4214
The reaction of [Cp1IrCl2]2 (Cp* = η5 ? C5Me5) with the tridentate 3-thiapentane-1,5-dithiolate ligand, S(CH2CH2S?)2 (tpdt), led to the formation of [Cp1Ir(η3 ? tpdt)] (1) in 81% isolated yield. Subsequent reactions of 1 with [Cp1IrCl2]2 in 2:1 and 1:1 molar equiv ratios resulted in the formation of [Cp1Ir(μ ? η2:η3 ? tpdt)Cp1IrCl][PF6] (2) and [Cp1Irμ ? η2:η3 ? tpdt)Cp1IrCl][Cp1IrCl3] (3) in 86 and 79% yields, respectively, based on 1, whereas the reactions of 1 with [(COD)IrCl]2 (COD = 1,5-cyclooctadiene) in 2:1 and 1:1 molar equiv ratios resulted in the formation of the homo-bimetallic derivatives Cp1Ir(μ ? η1:η3 ? tpdt)(COD)IrCl (4) (92% yield) and [Cp1Ir(μ ? η2:η3 ? tpdt)(COD)Ir] [(COD)IrCl2] (5) (82% yield). Reactions between 1 and [(COD)RhCl]2, yielded the hetero-bimetallic derivatives Cp1Ir(μ ? η1:η3 ? tpdt)(COD)RhCl (6) and [Cp1Ir(μ ? η2:η3 ? tpdt)(COD)Rh][(COD)RhCl2] (7), in 92 and 93% yields, respectively. The reaction of 1 with methyl iodide gave mono-methylated derivative [Cp1Ir(η3-C4H8S3Me)]I (8) (93% yield). All these compounds have been comprehensively characterized. 相似文献
350.
A facile and bio-inspired route for the preparation of pure and highly crystalline metastable α-AgVO(3) is presented. Three kinds of proteins (bovine hemoglobin, bovine serum albumin, and lysozyme) were employed as inducer, which had substantial effects on the nucleation and growth of α-AgVO(3). Moreover, the amount of proteins also played a key role over the morphology and crystalline of products. The VO(3)(-)/protein complex acted as a driver to induce the formation of metastable phase, which was confirmed by resonance Rayleigh scattering and UV-vis absorption spectra. The results indicated that tailoring an interaction between protein and inorganic molecules was the key in bio-inspired selective synthesis of metastable phase, which may find applications in the design of other new functional inorganic materials. 相似文献