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11.
Mengya Kong Yuyang Gu Yingjie Chai Jiaming Ke Yulai Liu Xincheng Xu Zhanxian Li Wei Feng Fuyou Li 《中国科学:化学(英文版)》2021,(6):974-984
Luminescence nanothermometry makes non-invasive and real-time temperature readings possible in living animals. However,the spectral fluctuation in tissues and fluids, as well as the interaction between fluorophores and environment hinders accuracy of the thermometry. Here, we report a luminescence lifetime-based nanothermometry which specifically addresses this problem. A temporal based calibration(lifetime sensing) in the NIR range, an endogenous thermal response as well as a polymer encapsulation evading environmental factors, altogether help to pinpoint temperature in vivo. Thanks to the highly condensed NdYb ions in a well-protected tiny core-shell nanocrystal(overall 11 nm), a temperature sensitivity about 2.07% K~(-1)(with 5% Yb~(3+) doped nanoparticles) and an accuracy of 0.27 K(with 25% Yb~(3+) doped nanoparticles) in biological fluids are achieved.Hopefully, combining thermally activated energy transfer nanothermometer with anti-interference lifetime thermometry would provide a more accurate temperature measurement for biological and preclinical studies. 相似文献
12.
In this paper, a quantum secure direct communication protocol using ensembles with the same density matrix is proposed. The two communication parties can realize the message transmission using this method through a quantum channel, each bit of information can be transmitted using an ensemble and read out through global measurement.The eavesdropping behavior can be detected through the channel diagnoses. 相似文献
13.
Nemeshwaree Behary Sandy Eap Aurlie Cayla Feng Chai Nadia Benkirane-Jessel Christine Campagne 《Molecules (Basel, Switzerland)》2022,27(12)
Textile scaffolds that are either 2D or 3D with tunable shapes and pore sizes can be made through textile processing (weaving, knitting, braiding, nonwovens) using microfilaments. However, these filaments lack nano-topographical features to improve bone cell adhesion and proliferation. Moreover, the diameter of such filaments should be higher than that used for classical textiles (10–30 µm) to enable adhesion and the efficient spreading of the osteoblast cell (>30 µm diameter). We report, for the first time, the fabrication of biodegradable nanostructured cylindrical PLLA (poly-L-Lactic acid) microfilaments of diameters 100 µm and 230 µm, using a single step melt-spinning process for straightforward integration of nano-scale ridge-like structures oriented in the fiber length direction. Appropriate drawing speed and temperature used during the filament spinning allowed for the creation of instabilities giving rise to nanofibrillar ridges, as observed by AFM (Atomic Force Microscopy). These micro-filaments were hydrophobic, and had reduced crystallinity and mechanical strength, but could still be processed into 2D/3D textile scaffolds of various shapes. Biological tests carried out on the woven scaffolds made from these nano-structured micro filaments showed excellent human bone cell MG 63 adhesion and proliferation, better than on smooth 30 µm- diameter fibers. Elongated filopodia of the osteoblast, intimately anchored to the nano-structured filaments, was observed. The filaments also induced in vitro osteogenic expression, as shown by the expression of osteocalcin and bone sialoprotein after 21 days of culture. This work deals with the fabrication of a new generation of nano-structured micro-filament for use as scaffolds of different shapes suited for bone cell engineering. 相似文献
14.
实验研究了大模面积光子晶体光纤飞秒激光器在近零色散点展宽脉冲锁模的束缚态运转.获得了双脉冲束缚态锁模,以及脉冲间隔不相等的多脉冲束缚态锁模,实验发现束缚态的子脉冲间距具有随机性.通过建立光纤锁模激光器的数值模型,分析了激光器束缚态锁模建立的动力学过程,在一定抽运强度下,激光器存在多个稳态,或者单脉冲运转,或者子脉冲间隔不相等的束缚态运转,这取决于锁模建立阶段半导体可饱和吸收镜(SESAM)对噪声信号的随机提取.并提出了抑制束缚态的方法,模拟得出此项技术可直接获得的最大单脉冲能量为19.6 nJ,考虑到40%左右的压缩损耗,可得到压缩至76 fs的最短脉冲,单脉冲能量为11.8 nJ.数值模拟结果能很好的与实验相符合. 相似文献
15.
Ji-Wu Huang Chuang-Jun Li Jing-Zhi Yang Chuan Li Yu Zhang Ke Liu Yue Yu Jian-Dong Jiang Dong-Ming Zhang 《中国化学》2021,(5):1129-1137
Main observation and conclusion
Eight new polycyclic phloroglucinol meroterpenoids guajamers A-H (1-8),a methylated benzoylphloroglucinol meroterpenoid guajamer... 相似文献
16.
Ren Y Acuña UM Jiménez F García R Mejía M Chai H Gallucci JC Farnsworth NR Soejarto DD Carcache de Blanco EJ Kinghorn AD 《Tetrahedron》2012,68(12):2671-2678
Six new (1-6) and eight known germacranolide-type sesquiterpene lactones, along with several known phenylpropanol coumarates and methylated flavonoids, were isolated from the leaves of Piptocoma rufescens, collected in the Dominican Republic. The new compounds were identified by analysis of their spectroscopic data, with the molecular structure of 3 being established by single-crystal X-ray diffraction. The absolute configurations of the sesquiterpene lactones isolated were determined from their CD and NOESY NMR spectra, together with the analysis of Mosher ester reactions. Bioassay screening results showed the majority of the sesquiterpene lactones isolated (1-13) to be highly cytotoxic toward the HT-29 human colon cancer cell line, with the most potent compound being 15-deoxygoyazensolide (10, IC(50), 0.26 μM). In addition, several of the sesquiterpene lactones exhibited NF-κB (p65) inhibitory activity. 相似文献
17.
18.
Zaizhe Cheng Wenqiang Zhou Guojun Lan Xiucheng Sun Xiaolong Wang Chuan Jiang Ying Li 《Journal of Energy Chemistry》2021,(12):550-557
Methanol steam reforming (MSR) is an attractive approach to produce hydrogen for fuel cells.Due to the limited catalyst loading volume and frequent start-ups an... 相似文献
19.
T. Sandrock T. Danger E. Heumann G. Huber B. H. T. Chai 《Applied physics. B, Lasers and optics》1994,58(2):149-151
We report, to our knowledge for the first time, Continuous Wave (CW) laser emission at room temperature of Pr:LiYF4 (Pr.YLF) at six wavelengths: 522, 545, 607, 639.5, 720 and 907.4 nm. The pump source was an argon-ion laser tuned to a wavelength of = 457.9 nm. The maximum output powers at 522 nm (3Pi 3H5) and 639.5 nm (3P0 3F2) were 144 and 266 mW, respectively. We also observed CW laser action of Pr:GdLiF4 (Pr: GLF) at = 639 nm and of Pr:KYF4 (Pr: KYF) at = 642.5 nm. 相似文献
20.
本文提出了一种新的测定间三联苯和对三联苯的同步扫描-SS-RTP法。固体基质选用慢速定量滤纸,重原子盐为Tl2SO4。以激发单色器和发射单色器的波长差△λ=180nm进行同步扫描,其同步特征峰间三联苯为450nm,对三联苯为490nm(均指发射波长)。间三联苯可直接由该特征峰的高度进行定量测定。对三联苯在490nm处的特征峰略受间三联苯同步拖尾的影响,其峰值信号需加校正。间三联苯和对三联苯的线性范围分别为0.46~92ng/斑点和0.46~46ng/斑点 相似文献