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51.
Fluorescence switch plays a vital role in bioelectronics and bioimaging.Herein,we presented a new kind of facile electrostatic complex nanoparticles(ECNs)for fluorescence switching in cells and marking of individual cell.The ECNs were prepared by mixing positively charged poly(6-(2-(thiophen-3-yl)ethoxy)hexyl trimethylammonium bromide)(PT)and negatively charged diarylethene sodium salt(DAECOONa).DAE-COONa is a photoswitchable molecule which can be transformed between the ring-closed fo rm and ring-open form under the irradiation of UV or visible light.The closed-form of DAE-COONa can efficie ntly quench the fluorescence of PT through intermolecular energy transfer,while the open form of DAE-COONa does not influence the emission of PT.Thus,the fluorescence of ECNs can be modulated by light irradiation,and the ECNs with good fluorescence switching performance have been employed for fluorescence imaging and individual cell lighting up process successfully.We demonstrate that the electrostatic complex strategy provides a facile method to construct fluorescence switch fo r selective cell marking and imaging applications. 相似文献
52.
The chiral phosphoric acid catalyzed asymmetric[3+2]annulation of substituted 2-vinylindoles with azlactones has been established.This reaction represented a practical approach for the synthesis of structurally diverse pyrrolo[1,2-a]indoles with two vicinal stereocenters including one tetrasubstituted stereocenter in good yields and good stereoselectivities under mild conditions. 相似文献
53.
CAO Mengyao SUN Yueyang XIAO Mingshu LI Li LIU Xiaohui JIN Hong PEI Hao 《高等学校化学研究》2020,36(2):254-260
In spite of great development in nanoparticle-based drug delivery systems(DDSs)for improved therapeutic efficacy,it remains challenging for effective delivery of chemotherapeutic drugs to targeted tumor cells.In this work,we report a triangle DNA origami as targeted DDS for cancer therapy.DNA origami shows excellent biocompatibility and stability in cell culture medium for 24 h.In addition,the DNA origami structures conjugated with multivalent aptamers enable for efficient delivery of anticancer drug doxorubicin(Dox)into targeted cancer cell due to their targeting function,reducing side effects associated with nonspecific distribution.Moreover,we also demonstrated that the multivalent aptamer-modified DNA origami loading Dox exhibits prominent therapeutic efficacy in vitro.Accordingly,this work provides a good paradigm for the development of DNA origami nanostructure-based targeted DDS for cancer therapy. 相似文献
54.
Xiao-Chen Sun Xing-Chi Li Ze-Wei Xie Chen-Yue Yuan De-Jiu Wang Qian Zhang Xiao-Yu Guo Hao Dong Hai-Chao Liu Ya-Wen Zhang 《Journal of Energy Chemistry》2024,(4):475-483
The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported catalysts.Here,we report a synthetic strategy to upgrade Cu-CeO2 interfacial interaction by the pyrolysis of mixed metal-organic framework(MOF) structure.The obtained highly dispersed Cu/CeO2- MOF catalyst via this strategy was used to catalyze water-gas shift reaction(WGSR),which exhibited high activity of 40.5 μmolCO 相似文献
55.
Zhi-Cheng Gong Cheng-Yu Shen Tian-Hua Mao Chang-Pu Sun Yong Li Hao Fu 《中国科学:物理学 力学 天文学(英文版)》2023,(7):59-65
Measurement-based feedback has been adopted as an efficient cooling scheme capable of suppressing the thermal fluctuation of a mechanical resonator to a level limited by measurement imprecision.We present a scheme of squeezed cooling in which the limit of feedback cooling imposed by the measurement imprecision is surpassed by parametrically squeezing the mechanical resonator in a periodically oscillating optical trap.To stabilize the parametrically amplified quadrature and simultaneously optimiz... 相似文献
56.
Hao Wang Shuling Liu Peng Wang Haonan Ge Yue Chen Hailu Wang Tengfei Xu Jiaxiang Guo Yuanchen Zou Wenrui Wei Ruiqi Jiang Fang Wang Piotr Martyniuk Jinshui Miao Weida Hu 《中国科学:物理学 力学 天文学(英文版)》2023,(9):90-97
Black phosphorus(BP) as a narrow-bandgap two-dimensional semiconductor material has been extensively studied. And the allotrope violet phosphorus(VP) exhibits wide bandgap properties extending the application in the visible light band. However,due to the Schottky barrier of metal/semiconductor contacts(M/S), further device application of VP is limited. Here, VP-based photodetectors with van der Waals-assisted contact were demonstrated, achieving quasi-Ohmic M/S contacts. The output characteristi... 相似文献
57.
Changlong Chen Vignyatha Reddy Tatagari Hao Lin Leon Shaw 《Journal of Energy Chemistry》2023,(3):240-245
In the past decade,the surging demand for portable electronics,electric vehicles,and stationary energy storage grids has triggered a noticeable rise in the production of Li-ion batteries(LIBs).However,this swift rise is now hindered by relying on the use of N-methyl-2-pyrrolidone(NMP),a repro-toxic solvent,in the current cathode processing of LIBs.To overcome this challenge,here we have investigated triethyl phosphate(TEP) as a greener alternative to NMP.The compatibility with polyvinylidene flu... 相似文献
58.
Jie Wang Aimin Wu Lei Xing Shuai Ran Wenhua Yu Xufeng Dong Hao Huang 《Journal of Energy Chemistry》2023,(11):217-226
Efficient, stable and economical catalysts play a crucial role in enhancing the kinetics of slow oxygen reduction reactions(ORR) in Aluminum-air batteries. Among the potential next-generation candidates,Ag catalysts are promising due to their high activity and low cost, but weaker oxygen adsorption has hindered industrialization. To address this bottleneck, Ag-alloying has emerged as a principal strategy. In this work, we successfully prepared Ag-Cu nanoparticles(NPs) with a rich eutectic phase ... 相似文献
59.
Jie Ren Hao Lou Nuo Xu Feng Zeng Gang Pei Zhandong Wang 《Journal of Energy Chemistry》2023,(5):182-206
Power-to-methane(P2M) processes, by converting electricity from renewable energy to H2 and then into other high value-added and energy-intense chemicals in the presence of active catalysts, have become an effective solution for energy storage. However, the fluctuating electricity from intermittent renewable energy leads to a dynamic composition of reactants for downstream methanation, which requires an excellent heterogeneous catalyst to withstand the harsh conditions. Based on these ... 相似文献
60.
Overview of finite elements simulation of temperature profile to estimate properties of materials 3D-printed by laser powder-bed fusion
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Habimana Jean Willy 李辛未 Yong Hao Tan 陈哲 Mehmet Cagirici Ramadan Borayek Tun Seng Herng Chun Yee Aaron Ong 李朝将 丁军 《中国物理 B》2020,(4):98-109
Laser powder bed fusion(LPBF),like many other additive manufacturing techniques,offers flexibility in design expected to become a disruption to the manufacturing industry.The current cost of LPBF process does not favor a try-anderror way of research,which makes modelling and simulation a field of superior importance in that area of engineering.In this work,various methods used to overcome challenges in modeling at different levels of approximation of LPBF process are reviewed.Recent efforts made towards a reliable and computationally effective model to simulate LPBF process using finite element(FE)codes are presented.A combination of ray-tracing technique,the solution of the radiation transfer equation and absorption measurements has been used to establish an analytical equation,which gives a more accurate approximation of laser energy deposition in powder-substrate configuration.When this new analytical energy deposition model is used in in FE simulation,with other physics carefully set,it enables us to get reliable cooling curves and melt track morphology that agree well with experimental observations.The use of more computationally effective approximation,without explicit topological changes,allows to simulate wider geometries and longer scanning time leading to many applications in real engineering world.Different applications are herein presented including:prediction of printing quality through the simulated overlapping of consecutive melt tracks,simulation of LPBF of a mixture of materials and estimation of martensite inclusion in printed steel. 相似文献