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991.
《Current Applied Physics》2020,20(11):1281-1287
In this study, the red-emitting phosphor-in-glass (PiG) using the CaAlSiN3: Eu2+ (CASN) phosphor is reported for the first time. The CASN: Eu2+ PiG samples with a maximum luminous flux of 25.1–29.4 for l minute at laser power of 1 W/mm2 was obtained using a low-temperature glass frit and GPS furnace. Despite the increase in the phosphor from 15 to 25 wt%, the PiG produced at low temperature of 380 °C showed robust properties. Finally, the red PiG module designed for rear lamp applications maintains over 90% lumens for a minute at 350 mA and achieves an intense red light having a color temperature of 4589 K. 相似文献
992.
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994.
上海市力学学会成立于1959年9月20日,到今年正好是一个甲子.60个春秋真实写照了上海市力学学会的建立、成长、发展与壮大的过程.60年来,在上海市科协的领导和中国力学学会的指导下,在各团体成员单位的大力支持下,上海市力学学会一代代力学工作者薪火相传、开拓耕耘,历届理事会及下属工作委员会和专业委员会团结奋进、不断创新,广大会员踊跃参与,为上海力学大力发展、力学人才精心培养、力学知识科学普及、力学服务国家发展战略和区域经济建设中做出了重要贡献,学会持续发展壮大.在庆祝力学学会成立六十周年之际,让我们共同抒怀上海力学六十年薪火相传、回顾近10年重要发展,展望上海力学新时代. 相似文献
995.
Maria Michela Salvatore Ilaria Di Lelio Marina DellaGreca Rosario Nicoletti Francesco Salvatore Elia Russo Gennaro Volpe Andrea Becchimanzi Alla Eddine Mahamedi Akila Berraf-Tebbal Anna Andolfi 《Molecules (Basel, Switzerland)》2022,27(7)
An undescribed 5,6-dihydropyran-2-one, namely diplopyrone C, was isolated and characterized from the cultures of an isolate of the fungus Diplodia corticola recovered from Quercus suber in Algeria. The structure and relative stereostructure of (5S,6S,7Z,9S,10S)-5-hydroxy-6-(2-(3-methyloxiran-2-yl)vinyl)-5,6-dihydro-2H-pyran-2-one were assigned essentially based on NMR and MS data. Furthermore, ten known compounds were isolated and identified in the same cultures. The most abundant product, the tetracyclic pimarane diterpene sphaeropsidin A, was tested for insecticidal effects against the model sucking aphid, Acyrthosiphon pisum. Results showed a toxic dose-dependent oral activity of sphaeropsidin A, with an LC50 of 9.64 mM. 相似文献
996.
Considering the potential bioactivities of natural product and natural product-like compounds with highly complex and diverse structures, the screening of collections and small-molecule libraries for high-throughput screening (HTS) and high-content screening (HCS) has emerged as a powerful tool in the development of novel therapeutic agents. Herein, we review the recent advances in divergent synthetic approaches such as complexity-to-diversity (Ctd) and biomimetic strategies for the generation of structurally complex and diverse indole-based natural product and natural product-like small-molecule libraries. 相似文献
997.
阿根廷生物化学家卢伊斯·弗德里科·莱洛伊尔因发现糖核苷酸及其在碳水化合物生物合成中的作用而获1970年诺贝尔化学奖。莱洛伊尔一生不仅致力于科学研究,还积极推动阿根廷的大学和医学教育,建立了致力于科学研究的坎波马尔基金会。本文回顾了莱洛伊尔的科研成果、相关研究背景以及他的科研历程,分析了他能够获得成功的因素;讨论了名师对科研人员学术指导的重要作用、及时调节研究过程中产生的各类情绪的积极意义以及敢于大胆跨界探索对科研人员的重要性。 相似文献
998.
Although conventional medicine, chemical drug synthesis and pharmaceutical research are advancing at a rapid pace, nature remains a major supplier of biological molecules. Natural bioactive compounds are studied closely especially as an alternative to the limitations of conventional therapy in many diseases, melanoma being one of them. Malignant melanoma is a highly aggressive type of cancer, and the current methods of treatment used are cryotherapy, external surgery, radiation therapy, chemotherapy, photodynamic therapy, biological therapy, and targeted drug therapy. Unfortunately, these treatment methods are often inefficient, extremely expensive and cause many side effects, which is why focusing on melanoma chemoprevention and adjuvant therapy with natural herbal phytoconstituents is an emerging strategy to prevent, cure or treat melanoma. This review aims to examine the latest discoveries in terms of potential natural bioactive compounds that possess important activity against the development and spread of murine melanoma cancer. In particular, the use of different phytochemicals such as phenolic acids, flavonoids, anthocyanins, terpenoids, essential oils and carotenoids in vitro and in vivo models will be discussed. These data are helpful in guiding researchers in the direction of studying phytonutrients with important effects in the prevention and treatment of melanoma. 相似文献
999.
Raluca Pele Gabriel Marc Anca Stana Ioana Ionu Cristina Nastas Brîndua Tiperciuc Ilioara Oniga Adrian Pîrnu Laurian Vlase Ovidiu Oniga 《Molecules (Basel, Switzerland)》2022,27(8)
Considering the important damage caused by the reactive oxygen (ROS) and nitrogen (RNS) species in the human organism, the need for new therapeutic agents, with superior efficacy to the known natural and synthetic antioxidants, is crucial. Quinazolin-4-ones are known for their wide range of biological activities, and phenolic compounds display an important antioxidant effect. Linking the two active pharmacophores may lead to an increase of the antioxidant activity. Therefore, we synthesized four series of new hybrid molecules bearing the quinazolin-4-one and phenol scaffolds. Their antioxidant potential was evaluated in vitro, considering different possible mechanisms of action: hydrogen atom transfer, ability to donate electrons and metal ions chelation. Theoretical quantum and thermodynamical calculations were also performed. Some compounds, especially the ortho diphenolic ones, exerted a stronger antioxidant effect than ascorbic acid and Trolox. 相似文献
1000.