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991.
Jun-Fan Ding Rui Xu Chong Yan Bo-Quan Li Hong Yuan Jia-Qi Huang 《Journal of Energy Chemistry》2021,(8):306-319
Solid electrolyte interphase (SEI) has been widely recognized as the most important and the least understood component in lithium batteries.Considering the intr... 相似文献
992.
NANO SCIENCE AND ENGINEERING IN SOLID MECHANICS 总被引:3,自引:2,他引:1
Ken P. Chong 《Acta Mechanica Solida Sinica》2008,21(2):95-103
According to National Science Foundation (NSF) Director A. Bement, ‘Transformative research is... research driven by ideas that stand a reasonable chance of radically changing our understanding of an important existing scientific concept or leading to the creation of a new paradigm or field of science is also characterized by its challenge to current understanding or its pathway to new frontiers.' Nanotechnology is one of such frontiers. It is the creation of new materials, devices and systems at the molecular level--phenomena associated with atomic and molecular interactions strongly influence macroscopic material properties with significantly improved mechanical, optical, chemical, electrical... properties. Former NSF Director Rita Colwell in 2002 declared, ‘nanoscale technology will have an impact equal to the Industrial Revolution'. The transcendent technologies include nanotechnology, microelectronics, information technology and biotechnology as well as the enabling and supporting mechanical and civil infrastructure systems and materials. These technologies are the primary drivers of the twenty first century and the new economy. Mechanics is an essential eleraent in all of the transcendent technologies. Research opportunities, education and challenges in mechanics, including experimental, numerical and analytical methods in nanomechanics, carbon nano-tubes, bio-inspired materials, fuel cells, as well as improved engineering and design of materials are presented and discussed in this paper. 相似文献
993.
994.
不同光照下,如何消除或减小反演数据差异,提高检测精度,是目前南疆冬枣户外检测中遇到的一大难题,因此通过用高光谱相机获得的南疆冬枣二向反射分布函数(BRDF)测量值,采用最小二乘法拟合Roujean模型和Ross-Li模型的参数,最后对比Roujean模型和Ross-Li模型反演的结果,提出何种天气何段波长用何种模型反演... 相似文献
995.
Narae Hwang Eunbin Chong Hyeonju Oh Hee Won Cho Ji Won Lee Ki Woong Sung Soo-Youn Lee 《Molecules (Basel, Switzerland)》2021,26(11)
Homovanillic acid (HVA) and vanillylmandelic acid (VMA) are end-stage metabolites of catecholamine and are clinical biomarkers for the diagnosis of neuroblastoma. For the first time in Korea, we implemented and validated a liquid chromatography tandem mass spectrometry (LC–MS/MS) assay to measure urinary concentrations of HVA and VMA according to Clinical and Laboratory Standards Institute guidelines. Our LC–MS/MS assay with minimal sample preparation was validated for linearity, lower limit of detection (LOD), lower limit of quantification (LLOQ), precision, accuracy, extraction recovery, carryover, matrix effect, and method comparison. A total of 1209 measurements was performed to measure HVA and VMA in spot urine between October 2019 and September 2020. The relationship between the two urinary markers, HVA and VMA, was analyzed and exhibited high agreement (89.1% agreement, kappa’s k = 0.6) and a strong correlation (Pearson’s r = 0.73). To our knowledge, this is the first study to utilize LC–MS/MS for simultaneous quantitation of spot urinary HVA and VMA and analyze the clinical application of both markers on a large scale for neuroblastoma patients. 相似文献
996.
Hua Yang Bai Wei Wang Sheng Wu Yunbo Cui Shengtao Sun Zhe Xiao Chong 《中国科学:化学(英文版)》2021,64(11):1970-1975
Science China Chemistry - The two-dimensional (2D) structure often leads to unusual phenomena for the impact of confined mean free path of carrier scattering. As a quasi-2D layered material,... 相似文献
997.
Jianhua Zhu Aik Chong Lua 《Journal of polymer science. Part A, Polymer chemistry》2021,59(20):2295-2308
Interfacial polymerization technology was employed to immobilize silver (Ag) nanoparticles on the surface of commercial polyethersulfone (PES) membrane to develop antibacterial and antifouling ultrafiltration membrane. Ag nanoparticles were prepared from the reduction of silver nitrate (AgNO3) by sodium borohydride in the presence of polyethyleneimine (PEI) as the stabilizer. The encapsulated Ag nanoparticles in the PEI solution were embedded into the PEI membrane when trimesoyl chloride solution was used to crosslink the PEI solution with the PES membrane, forming Ag-polyamide (PA) networks through the interfacial polymerization reaction. Experimental results showed that the membrane prepared with 50 mmol/L of AgNO3 and 20 mmol/L of PEI had the optimized antibacterial effect against Escherichia coli. Bacterial concentration and species were also investigated. Exiguobacterium aestuarii and Staphylococcus aureus which are gram-positive bacteria, needed significantly more time for the Ag-PA/PES membrane to kill the bacteria completely when compared to E.coli and Vibrio coralliilyticus which are gram-negative bacteria. This study showed that Ag nanoparticles impregnated in membrane surfaces were 100% effective in killing various types of marine bacteria and bacteria in the seawater collected off Sentosa Island in Singapore. These membranes exhibit excellent antibacterial and antifouling properties which can be used to kill bacteria in ballast water and seawater. 相似文献
998.
Unraveling Ultrafast Photoinduced Proton Transfer Dynamics in a Fluorescent Protein Biosensor for Ca2+ Imaging
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Longteng Tang Dr. Weimin Liu Yanli Wang Dr. Yongxin Zhao Breland G. Oscar Prof. Dr. Robert E. Campbell Prof. Dr. Chong Fang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6481-6490
Imaging Ca2+ dynamics in living systems holds great potential to advance neuroscience and cellular biology. G‐GECO1.1 is an intensiometric fluorescent protein Ca2+ biosensor with a Thr‐Tyr‐Gly chromophore. The protonated chromophore emits green upon photoexcitation via excited‐state proton transfer (ESPT). Upon Ca2+ binding, a significant population of the chromophores becomes deprotonated. It remains elusive how the chromophore structurally evolves prior to and during ESPT, and how it is affected by Ca2+. We use femtosecond stimulated Raman spectroscopy to dissect ESPT in both the Ca2+‐free and bound states. The protein chromophores exhibit a sub‐200 fs vibrational frequency shift due to coherent small‐scale proton motions. After wavepackets move out of the Franck–Condon region, ESPT gets faster in the Ca2+‐bound protein, indicative of the formation of a more hydrophilic environment. These results reveal the governing structure–function relationship of Ca2+‐sensing protein biosensors. 相似文献
999.
1000.
Jing Nie Xiuyi Yang Qing-Xu Yu Chong Li 《International Journal of Theoretical Physics》2014,53(12):4291-4301
We have studied the non-Markovian decoherence dynamics of the two-level system in a composite environment, which consists of a spin-star environment and a boson reservoir. By use of the measures presented recently, we theoretically study the non-Markovianity of the dynamics of the model. 相似文献