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121.
3-(噁唑-5-基)吲哚类天然产物如Pimprinine,Streptochlorin等,广泛存在于海洋微生物中,因其具有多样的生物活性,在医药和农药领域中很有研究潜力.3-(噁唑-5-基)吲哚类天然产物的合成方法有很多研究报道,在吲哚结构上构建噁唑环是合成此类天然产物的关键.总结了已报道的3-(噁唑-5-基)吲哚类天然产物的生物活性,并对构建3-(噁唑-5-基)吲哚骨架的合成方法及部分主要反应机理进行了综述,探讨了3-(噁唑-5-基)吲哚类骨架作为一种优势活性结构在未来的应用前景. 相似文献
122.
Jiajing Wu Dr. Jianyu Tong Dr. Yuan Gao Dr. Aifei Wang Prof. Tao Zhang Prof. Hairen Tan Prof. Shuming Nie Prof. Zhengtao Deng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(20):7812-7816
A novel triphenylphosphine (TPP) treatment strategy was developed to prepare the near-infrared emission CsPbI3 nanocrystal (NC)-polymer composite thin-film luminescent solar concentrators (LSCs) featuring high absolute photoluminescence quantum yield (PLQY), low reabsorption, and high stability. The PL emission of the LSCs is centered at about 700 nm with 99.4±0.4 % PLQY and narrow full width at half maximum (FWHM) of 75 meV (30 nm). Compared with LSCs prepared with classic CsPbI3 NCs, the stability of the LSCs after TPP treatments has been greatly improved, even after long-term (30 days) immersion in water and strong mercury-lamp irradiation (50 mW cm−2). Owing to the presence of lone-pair electrons on the phosphorus atom, TPP is also used as a photoinitiator, with higher efficiency than other common photoinitiators. Large-area (ca. 75 cm2) infrared LSCs were achieved with a high optical conversion efficiency of 3.1 % at a geometric factor of 10. 相似文献
123.
The development of polymeric optical materials with a higher refractive index,transparency in the visible spectrum region and easier processability is increasingly desirable for advanced optical applications such as microlenses,image sensors,and organic light-emitting diodes.Most acrylates have a low refractive index(around 1.50)which does not meet the high perfo rmance requirements of advanced optical materials.In this research,three novel acrylates were synthesized via a facile one-step approach and used to fabricate optical transparent polymers.All of the polymers reveal good optical properties including high transparency(≥90%)in the visible spectrum region and high refractive index values(1.6363)at 550 nm.Moreover,nanostructures of these acrylate polymers with various feature sizes including nanogratings and photonic crystals were successfully fabricated using nanoimprint lithography.These results indicate that these acrylates can be used in a wide range of optical and optoelectronic devices where nanopatterned films with high refractive index and transparency are required. 相似文献
124.
Weidong Nie Guanghao Wu Jinfeng Zhang Li‐Li Huang Jingjing Ding Anqi Jiang Yahui Zhang Yanhong Liu Jingchao Li Kanyi Pu Hai‐Yan Xie 《Angewandte Chemie (International ed. in English)》2020,59(5):2018-2022
Exosomes hold great potential in therapeutic development. However, native exosomes usually induce insufficient effects in vivo and simply act as drug delivery vehicles. Herein, we synthesize responsive exosome nano‐bioconjugates for cancer therapy. Azide‐modified exosomes derived from M1 macrophages are conjugated with dibenzocyclooctyne‐modified antibodies of CD47 and SIRPα (aCD47 and aSIRPα) through pH‐sensitive linkers. After systemic administration, the nano‐bioconjugates can actively target tumors through the specific recognition between aCD47 and CD47 on the tumor cell surface. In the acidic tumor microenvironment, the benzoic‐imine bonds of the nano‐bioconjugates are cleaved to release aSIRPα and aCD47 that can, respectively, block SIRPα on macrophages and CD47, leading to abolished “don't eat me” signaling and improved phagocytosis of macrophages. Meanwhile, the native M1 exosomes effectively reprogram the macrophages from pro‐tumoral M2 to anti‐tumoral M1. 相似文献
125.
Wenhan Xu Michelle M. S. Lee Jing‐Jun Nie Zhihan Zhang Ryan T. K. Kwok Jacky W. Y. Lam Fu‐Jian Xu Dong Wang Ben Zhong Tang 《Angewandte Chemie (International ed. in English)》2020,59(24):9610-9616
Photodynamic therapy (PDT) has long been shown to be a powerful therapeutic modality for cancer. However, PDT is undiversified and has become stereotyped in recent years. Exploration of distinctive PDT methods is thus highly in demand but remains a severe challenge. Herein, an unprecedented 1+1+1>3 synergistic strategy is proposed and validated for the first time. Three homologous luminogens with aggregation‐induced emission (AIE) characteristics were rationally designed based on a simple backbone. Through slight structural tuning, these far‐red/near‐infrared AIE luminogens are capable of specifically anchoring to mitochondria, cell membrane, and lysosome, and effectively generating reactive oxygen species (ROS). Notably, biological studies demonstrated combined usage of three AIE photosensitizers gives multiple ROS sources simultaneously derived from several organelles, which gives superior therapeutic effect than that from a single organelle at the same photosensitizers concentration. This strategy is conceptually and operationally simple, providing an innovative approach and renewed awareness of improving therapeutic effect through three‐pronged PDT. 相似文献
126.
Na Li Honggang Nie Liping Jiang Guihua Ruan Fuyou Du Huwei Liu 《Journal of separation science》2020,43(15):3146-3163
The structural information and spatial distribution of molecules in biological tissues are closely related to the potential molecular mechanisms of disease origin, transfer, and classification. Ambient ionization mass spectrometry imaging is an effective tool that provides molecular images while describing in situ information of biomolecules in complex samples, in which ionization occurs at atmospheric pressure with the samples being analyzed in the native state. Ambient ionization mass spectrometry imaging can directly analyze tissue samples at a fairly high resolution to obtain molecules in situ information on the tissue surface to identify pathological features associated with a disease, resulting in the wide applications in pharmacy, food science, botanical research, and especially clinical research. Herein, novel ambient ionization techniques, such as techniques based on spray and solid‐liquid extraction, techniques based on plasma desorption, techniques based on laser desorption ablation, and techniques based on acoustic desorption were introduced, and the data processing of ambient ionization mass spectrometry imaging was briefly reviewed. Besides, we also highlight recent applications of this imaging technology in clinical researches and discuss the challenges in this imaging technology and the perspectives on the future of the clinical research. 相似文献
127.
Nonlinear Dynamics - Hysteresis is an inherent characteristic of piezoelectric materials that can be determined by not only the historical input but also the input signal frequency. Hysteresis... 相似文献
128.
综合性、设计性实验教学的探讨 总被引:1,自引:0,他引:1
综合性、设计性实验是培养学生的创新意识、创新精神和创新能力的有效措施;本文就开设综合性、设计性实验的意义、内涵、与基础实验的关系以及如何设计项目内容进行了初步的探讨。 相似文献
129.
Feng Wenjie Nie Hui Han Xu 《Acta Mechanica Solida Sinica》2007,20(3):275-282
This paper analyzes the dynamic magnetoelectroelastic behavior induced by a penny- shaped crack in a magnetoelectroelastic layer.The crack surfaces are subjected to only radial shear impact loading.The Laplace and Hankel transform techniques are employed to reduce the prob- lem to solving a Fredholm integral equation.The dynamic stress intensity factor is obtained and numerically calculated for different layer heights.And the corresponding static solution is given by simple analysis.It is seen that the dynamic stress intensity factor for cracks in a magnetoelec- troelastic layer has the same expression as that in a purely elastic material.And the influences of layer height on both the dynamic and static stress intensity factors are insignificant as h/a>2. 相似文献
130.