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1.
New lanthanide dimethyl-N-benzoylamidophosphate (HL) based tetrakis-complexes NEt4[LnL4] (Ln3+=La, Nd, Sm, Eu, Gd, Tb, Dy) are reported. The complexes are characterized by means of NMR, IR, absorption, and luminescent spectroscopy as well as by elemental, X-Ray, and thermal gravimetric analyses. The phenyl groups of the four ligands of the complex anion are directed towards one side, while the methoxy groups are directed in the opposite side, which makes the complexes under consideration structurally similar to calixarenes. The effect of changing the alkali metal counterion to the organic cation NEt4+ on the structure and properties of the tetrakis-complex [LnL4]- is analyzed. The complexes exhibit bright characteristic for respective lanthanides luminescence. Rather high intensity of the band of 5D07F4 transition, observed in the luminescence spectrum of NEt4[EuL4], is discussed based on theoretical calculations.  相似文献   
2.
Circularly polarized luminescence (CPL) has attracted attention as a next-generation light signal because of its carrying more information compared with normal and linearly polarized lights as well as its potential wide application in information fields. Recently, much attention has been paid to small organic molecules-based CPL emitters because of easy synthesis, fine structural modification at molecular level, and tunable wide range emission wavelength. This review highlights the development of small organic molecules-based CPL emitters in the past 5 years (2017–2021). The progress suggests that small organic molecules-based CPL emitters provide a simple and efficient way to generate CPL.  相似文献   
3.
Constructing molecular switches based on supramolecular assembly strategy is a research hotspot. In this work, we constructed an all visible-light-regulated supramolecular photo-switch based on pyridinium-modified diarylethene derivative (DTE-Me) and cucurbit[8]uril (CB[8]). CB[8] not only accelerated the photochromic process under 365 nm ultraviolet light but also shifted the absorption of open formed DTE-Me to the visible region, which led to efficient photocyclization under 450 nm visible light irradiation, while DTE-Me and DTE-Me/CB[7] remained unchanged under the same irradiating condition. Moreover, the complexation with CB[8] could induce the strong thermally activated delayed fluorescence (TADF) of guest molecular at 550 nm, which further shifted to 670 nm through two-step sequential energy transfer with sulforhodamine B (SRB) and Cy5. This energy transfer process could also be regulated with visible light, and the application for information encryption was also demonstrated. This assembly provides a convenient approach to construct all visible light-regulated TADF photo-switch.  相似文献   
4.
Supercapacitors (SCs) with high energy density and power density are a research hotspot. Herein, we report a flexible porous carbon membrane supercapacitor prepared by electrospinning polyacrylonitrile (PAN) with γ-cyclodextrin-MOF (γ-CD-MOF) and then carbonizing at 900 °C. BET results showed that the supercapacitor retained the skeleton of γ-CD, γ-CD-MOF and the pores formed by the spun-fibers, which were 0.73, 1.09 and 23–186 nm, respectively, showing a high specific surface area of 134.7 m2/g. The hierarchically porous structures ensure rapid charge transfer and ion diffusion, resulting in the PAN/γ-CD-MOF carbon electrode with a high capacity of 283.3 F/g. Moreover, the supercapacitor had a high energy density up to 17.5 Wh/kg and power density up to 6 kW/kg. Significantly, it showed excellent cycle stability with a capacitance retention of 97.5% after 6000 cycles. This work provides a supramolecular strategy to construct a flexible porous carbon membrane, which has potential for supercapacitor applications.  相似文献   
5.
6.
Cancer is a global issue and a serious threat to human health, one approach to treatment is starvation therapy. Recently, three-dimensional (3D) bioprinted tumor tissue models have been developed; however, whether 3D bioprinted models are good for in vitro study of starvation therapy is unclear. In this study, we studied the state of cells with serum-free medium in both 3D bioprinted scaffold and 2D cell cultures and found that 3D bioprinted cancer cells (3D cells) were more tolerant to serum starvation than 2D cells in terms of cell viability, cell proliferation, and M2 macrophage polarization. Moreover, the ratio of LC3II/I, an index of autophagy, increased much more in 3D cells, and 3D cells showed more autophagosomes than 2D cells after serum starvation, which indicated that the autophagy levels were higher in 3D cells. These results suggested that 3D cells are more tolerant to serum starvation than 2D cells, and autophagy may play an important role in this process.  相似文献   
7.
Luo  Y.  Hao  Y.-Q. 《JETP Letters》2022,116(5):288-292
JETP Letters - A GaAs/AlOx high index contrast subwavelength grating with TE polarization is presented for the GaAs-based vertical cavity surface emitting laser (VCSEL). The rigorous coupled wave...  相似文献   
8.
Li  Zh.  Zhang  Y.  Wang  R.  Jiang  D. 《Journal of Applied Spectroscopy》2022,89(2):371-380
Journal of Applied Spectroscopy - The concentration of heavy metals in drinking water is an important standard for water quality evaluation and water pipeline corrosion detection. This research...  相似文献   
9.
Bipolar electrode-based (BPE-based) electrochromic devices have garnered increasing attention in the past decade. These BPE-based electrochromic devices have been used for analytical health monitoring, point-of-care (POC) diagnostics, and chemical sensing. In this review, we highlight recent progress made regarding BPE-based electrochromic devices constructed for these analytical applications. Various, available electrochromic materials are summarized in the first section, after which the different device types (e. g., paper-based and self-powered) are discussed. Biological- and chemical-based analytical demonstrations of these devices are then reviewed. Finally, we conclude this review with a perspective on the future developments of BPE-based electrochromic devices in analytical applications.  相似文献   
10.
Adsorptive separation of C2H6 from C2H4 by adsorbents is an energy-efficient and promising method to boost the polymer grades C2H4 production. However, that C2H6 and C2H4 display very similar physical properties, making their separation extremely challenging. In this work, by regulating the pore environment in a family of chitosan-based carbon materials (C-CTS-1, C-CTS-2, C-CTS-4, and C-CTS-6)- we target ultrahigh C2H6 uptake and C2H6/C2H4 separation, which exceeds most benchmark carbon materials. Explicitly, the C2H6 uptake of C-CTS-2 (166 cm3/g at 100 kPa and 298 K) has the second-highest adsorption capacity among all the porous materials. In addition, C-CTS-2 gives C2H6/C2H4 selectivity of 1.75 toward a 1:15 mixture of C2H6/C2H4. Notably, the adsorption enthalpies for C2H6 in C-CTS-2 are low (21.3 kJ/mol), which will facilitate regeneration in mild conditions. Furthermore, C2H6/C2H4 separation performance was confirmed by binary breakthrough experiments. Under different ethane/ethylene ratios, C-CTS-X extracts a low ethane concentration from an ethane/ethylene mixture and produces high-purity C2H4 in one step. Spectroscopic measurement and diffraction analysis provide critical insight into the adsorption/separation mechanism. The nitrogen functional groups on the surface play a vital role in improving C2H6/C2H4 selectivity, and the adsorption capacities depend on the pore size and micropore volume. Moreover, these robust porous materials exhibit outstanding stability (up to 800 °C) and can be easily prepared on a large scale (kg) at a low cost (~$26 per kg), which is very significant for potential industrial applications.  相似文献   
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