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91.
Jiangguo Xiao Wentao Zhang Teshen Wang Jiyong Zhang Haiying Du 《Ceramics International》2021,47(9):12028-12037
A series of Na5Y(MoO4)4-yAy:Dy3+ (A = WO42?, VO43?; y = 0–0.05) phosphors were synthesized by the combustion method. Some of the MoO42? sites were occupied by WO42? and VO43? anions, which enhanced the luminescence property of Dy3+-doped Na5Y(MoO4)4. XRD results show that the crystal structures of the samples were consistent with the standard Na5Y(MoO4)4 phase. Under excitation at 352 nm, the Na5Y(MoO4)4-yAy:Dy3+ phosphors exhibited a characteristic blue emission at 485 nm and a yellow emission at 577 nm, which originated from the 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 transitions of Dy3+ ions, respectively. White light can be achieved by combining these blue and yellow emissions. After replacing MoO42? with WO42? and VO43? anions in Na5Y(MoO4)4:Dy3+, the luminescence intensity of Dy3+ was significantly improved due to the crystal field effect. The results indicate that Na5Y(MoO4)3.97(WO4)0.03:Dy3+ and Na5Y(MoO4)3.97(VO4)0.03:Dy3+ phosphors have good prospects for application in n-UV-excited w-LEDs. 相似文献
92.
Min Zhou Weinan Jiang Jiayang Xie Dr. Wenjing Zhang Zhemin Ji Jingcheng Zou Zihao Cong Ximian Xiao Jiawei Gu Prof. Runhui Liu 《ChemMedChem》2021,16(2):309-315
Poly(2-oxazoline)s have excellent biocompatibility and have been used as FDA-approved indirect food additives. The inert property of the hydrophilic poly(2-oxazoline)s suggests them as promising substitutes for poly(ethylene glycol) (PEG) in various applications such as anti-biofouling agents. It was recently reported that poly(2-oxazoline)s themselves have antimicrobial properties as synthetic mimics of host defense peptides. These studies revealed the bioactive properties of poly(2-oxazoline)s as a new class of functional peptide mimics, by mimicking host defense peptides to display potent and selective antimicrobial activities against methicillin-resistant Staphylococcus aureus both in vitro and in vivo, without concerns about antimicrobial resistance. The high structural diversity, facile synthesis, and potent and tunable antimicrobial properties underscore the great potential of poly(2-oxazoline)s as a class of novel antimicrobial agents in dealing with drug-resistant microbial infections and antimicrobial resistance. 相似文献
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The androgen receptor (AR) plays a crucial role in the occurrence and development of prostate cancer (PCa), and its signaling pathway remains active in castration-resistant prostate cancer (CRPC) patients. The resistance against antiandrogen drugs in current clinical use is a major challenge for the treatment of PCa, and thus the development of new generations of antiandrogens is under high demand. Recently, strategies for downregulating the AR have attracted significant attention, given its potential in the discovery and development of new antiandrogens, including G-quadruplex stabilizers, ROR-γ inhibitors, AR-targeting proteolysis targeting chimeras (PROTACs), and other selective AR degraders (SARDs), which are able to overcome current resistance mechanisms such as acquired AR mutations, the expression of AR variable splices, or overexpression of AR. This review summarizes the various strategies for downregulating the AR protein, at either the mRNA or protein level, thus providing new ideas for the development of promising antiandrogen drugs. 相似文献
96.
Limin Jin Xiaoli Yang Siufung Yu Puran Zheng Xian Chen Shumin Xiao Qinghai Song 《Journal of the American Ceramic Society》2022,105(9):5764-5773
Ultraviolet (UV) lasers with dynamic wavelength-tunability and high monochromaticity are crucial in a multitude of practical applications yet still remarkable challenges. Here, we show wide wavelength-tuning of single-mode UV lasing based on lanthanide-doped upconversion nanoparticles (UCNPs). The rationally designed Yb3+/Er3+/Tm3+/Gd3+/Ce3+ co-doped multilayer UCNPs, which exhibits a broad gain spectrum with the full width of half maximum of around 57 nm in the UV regime, are developed. More importantly, by taking advantages of a diffraction grating as the tuning component, stable single-mode emission can be achieved in the UCNPs-based external-cavity-extended Fabry–Pérot laser at room temperature. Specifically, the lasing threshold is around 137 µJ cm–2, which is two orders of magnitude lower than that in the previously reported articles. Precise wavelength-tuning from 310 to 363 nm can be realized by adjusting the Littrow angle. This achievement highlights a portable alternative to continuously wideband-tunable UV lasers and opens up new opportunities for constructing compact solid-state UV photon sources. 相似文献
97.
Multimedia Tools and Applications - Video-text cross-modal retrieval is significant to computer vision. Most of existing works focus on exploring the global similarity between modalities, but... 相似文献
99.
目的 为比较大豆油体、单甘脂和蔗糖酯三种成分对蛋糕烘焙学特征的影响。方法 本文通过对蛋糕面胚比容、质构,蛋糕面糊比重、黏度和表面气孔特性以及理化指标检测,并对蛋糕进行感官评定进行测试。结果 结果表明,大豆油体最适添加量为4.5%。大豆油体能增加蛋糕的黏度,有助于形成稳定的乳化体系,并且大豆油体蛋糕的酸价、过氧化值和反式脂肪酸检测结果符合国家标准。结论 大豆油体和乳化剂能显著提高豆乳奶油蛋糕的比容,降低硬度,从而改善蛋糕的品质特性。 相似文献
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