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161.
Ma  Chao  Wan  Minjie  Xu  Yunkai  Ren  Kan  Qian  Weixian  Chen  Qian  Gu  Guohua 《Applied Intelligence》2022,52(3):2785-2800
Applied Intelligence - Infrared target tracking plays an important role in both civil and military fields. The main challenges in designing a robust and high-precision tracker for infrared...  相似文献   
162.
A novel drug-loaded pathogen-mimicking nanocomplex (MSN-DOX-SP-LPS) has been constructed for synergistic chemo-immunotherapy.
  相似文献   
163.
Here we develop a strategy using near infrared (NIR) modulation of telomerase activity based on gold nanocage@smart polymer system. Using this biocompatible design, we can regulate cellular behavior. This system has been used in vivo by taking advantages of NIR. This is the first example for optical modulation of telomerase activity in living cells and tissues.
  相似文献   
164.
165.
Tetragonal BiFeO3 (BFO), which has a giant spontaneous polarization, has attracted a great deal of attention recently. In this paper, we systematically study the structural, magnetic, electronic and optic properties of BFO, BiFe0.75Mn0.25 O 3 (BFMM), and BiFe0.75Ti0.125Mn0.125 O 3 (BFMT). Results show that doping Ti and Mn into the Fe sites increases the c/a ratio and enhances the magnetization of BiFeO3 from 0 to 5 μB. The crystal symmetry changes from orthogonality to tetragonality with half of the Mn atoms being replaced by Ti in BiFe0.75Mn0.25 O 3, which suppresses the energy splitting of the Mn 3d orbitals and thus enlarge the band gap to 1.21 eV for BiFe0.75Ti0.125Mn0.125 O 3. Our calculated Bader charge and charge density difference show that the smallest volume of BiFe0.75Mn0.25 O 3 arises from the strong Mn–O bonds in BiFe0.75Mn0.25 O 3. Further investigations indicate similar optical behaviors for BiFeO3 and BiFe0.75Ti0.125Mn0.125 O 3. However, BiFe0.75Mn0.25 O 3 exhibits strong absorption in the infrared region for the transition from O 2p to Mn \({e_{g}^{2}}\) and \(t_{2g}^{3}\).  相似文献   
166.
The surface energy and surface stability of Ag nanocrystals (NCs) are under debate because the measurable values of the surface energy are very inconsistent, and the indices of the observed thermally stable surfaces are apparently in conflict. To clarify this issue, a transmission electron microscope is used to investigate these problems in situ with elaborately designed carbon‐shell‐capsulated Ag NCs. It is demonstrated that the {111} surfaces are still thermally stable at elevated temperatures, and the victory of the formation of {110} surfaces over {111} surfaces on the Ag NCs during sublimation is due to the special crystal geometry. It is found that the Ag NCs behave as quasiliquids during sublimation, and the cubic NCs represent a featured shape evolution, which is codetermined by both the wetting equilibrium at the Ag–C interface and the relaxation of the system surface energy. Small Ag NCs (≈10 nm) no longer maintain the wetting equilibrium observed in larger Ag NCs, and the crystal orientations of ultrafine Ag NCs (≈6 nm) can rotate to achieve further shape relaxation. Using sublimation kinetics, the mean surface energy of Ag NCs at 1073 K is calculated to be 1.1–1.3 J m?2.  相似文献   
167.
Whelk‐like polypyrrole (PPy) arrays film is successfully prepared by electropolymerization of pyrrole in the presence of low‐surface‐energy tetraethylammonium perfluorooctanesulfonate (TEAPFOS) as dopant. The underwater wettability of PPy whelk‐like arrays can be successfully tuned by electrical doping/dedoping of PFOS ions. Interestingly, CCl4 droplets with microliter‐size as a representative sample are gathered together to form a larger droplet underwater at the potential of +0.8 V (vs Ag/AgCl), because PPy is in its PFOS‐doped states. Note that CCl4 droplet can climb uphill successfully on the inclined whelk‐like arrays PPy film under the applied potential of ?1.0 V (vs Ag/AgCl), which may be attributed to wettability gradient derived from different oxidation states of PPy induced by electrochemical potential. These results may provide a simple strategy for on‐demand manipulation of organic droplets underwater at low voltage.  相似文献   
168.
Ren  Wuyang  Li  Handong  Gao  Lei  Li  Yong  Zhang  Zhongyang  Long  Chengjia  Ji  Haining  Niu  Xiaobin  Lin  Yuan  Wang  Zhiming 《Nano Research》2017,10(1):247-254
Nano Research - Thermal transport in superlattices is governed by various phonon-scattering processes. For extracting the phonon-scattering contribution of hetero-interfaces in chalcogenide...  相似文献   
169.
Zinc oxide nanoparticles (ZnO NPs),as a new type of pH-sensitive drug carrier,have received much attention.ZnO NPs are stable at physiological pH,but can dissolve quickly in the acidic tumor environment (pH < 6) to generate cytotoxic zinc ions and reactive oxygen species (ROS).However,the protein corona usually causes the non-specific degradation of ZnO NPs,which has limited their application considerably.Herein,a new type of pH-sensitive nanoreactor (ZnO-DOX@F-mSiO2-FA),aimed at reducing the non-specific degradation of ZnO NPs,is presented.In the acidic tumor environment (pH < 6),it can release cytotoxic zinc ions,ROS,and anticancer drugs to kill cancer cells effectively.In addition,the fluorescence emitted from fluorescein isothiocyanate (FITC)-labeled mesoporous silica (F-mSiO2) and doxorubicin (DOX) can be used to monitor the release behavior of the anticancer drug.This report provides a new method to avoid the non-specific degradation of ZnO NPs,resulting in synergetic therapy by taking advantage of ZnO NPs-induced oxidative stress and targeted drug release.  相似文献   
170.
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