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Photoresponsive cholesteric liquid crystals (CLCs) can selectively reflect colors upon exposure. However, achieving simultaneous erasure rewriting and color tuning in CLCs through light exposure remains a formidable challenge. Interestingly, CLCs doped with azobenzene show rapid RGB color shifts when exposed to 365 nm wavelength light within a few seconds. This fully reversible process is also easily attainable under 405 nm wavelength irradiation. Furthermore, intense light induces isomerization in the azobenzene molecules, disrupting the molecular arrangement of the liquid crystals and facilitating the transition from a planar state (P-state) to a focal conic state (FC-state). This transition leads to the complete elimination of reflected colors in CLCs. Alongside mechanical stress and electrical responsiveness, these properties make CLCs doped with azobenzene highly attractive and applicable in diverse areas such as color displays, information encryption, and anti-counterfeiting. [ABSTRACT FROM AUTHOR]

In this paper, we give several generalization and refinement of numerical radius inequalities of bounded linear operators on a complex Hilbert space. It's shown that the bounds obtained here are stronger than the known bounds of numerical radius inequalities. Moreover, we use the properties of operator convex functions to obtain several interpolation inequalities of numerical radius. [ABSTRACT FROM AUTHOR]

In this work, we propose a liquid crystal (LC)-based double-dipole phase shifter. By manipulating the electric field, we change the resonant frequency and phase of the electromagnetic wave by deecting the orientation of LC molecules. We made the LC-based device with a 30x30 array of two parallel unequal dipoles on a Quartz substrate. The substrate has an area and thickness of 4 x 4 cm² and 480 µm, respectively. The experimental results show that the phase shift of 0°-385.4° is achieved at 94 GHz by changing the applied bias voltage on the LC layer from 0V to 8.4 V. The phase shift is greater than 360° in the range 91.75-94.85 GHz. When the LC molecules are most significantly affected by the electric field, the maximum precision of phase shift is 4.08° with a bias voltage of 2 mV. [ABSTRACT FROM AUTHOR]

The performance of organic thin film transistors (OTFTs) is heavily dependent on the interface property between the organic semiconductor and the dielectric substrate. Device fabrication with bottom-gate architecture by depositing the semiconductors with a solution method is highly recommended for cost-effectiveness. Surface modification of the dielectric layer is employed as an effective approach to control film growth. Here, we perform surface modification via a self-assembled monolayer of silanes, a spin-coated polymer layer or UV-ozone cleaning, to prepare surfaces with different surface polarities and morphologies. The semiconductor is inkjet-printed on the surfacetreated substrates as single-line films with overlapping drop assignment. Surface morphologies of the dielectric before film deposition and film morphologies of the inkjet-printed semiconductor are characterized with polarized microscopy and AFM. Electrical properties of the films are studied through organic thin-film transistors with bottom-gate/bottom-contact structure. With reduced surface polarity and nanoscale aggregation of silane molecules on the substrates, semiconductor nucleates from the interior interface between the ink solution and the substrate, which contributes to film growth with higher crystal coverage and better film quality at the interface. Surface treatment with hydrophobic silanes is a promising approach to fabrication of high performance OTFTs with nonpolar conjugated molecules via solution methods. [ABSTRACT FROM AUTHOR]

This study presents the design and experiment of a terahertz reflective phase shifter based on liquid crystal. The proposed voltage-tunable phase shifter takes advantage of the variable permittivity of the liquid crystal, adjusted by an external electric field, providing tunable reflective phase shift of terahertz (THz) waves. We analysed the performance of this phase shifter using a simple isotropic and homogeneous model considering the angle of incidence. The phase variation was achieved in a range greater than 360° and frequencies from 349 to 361 GHz. An array constituted of 900 patch elements was fabricated using the photolithographic process. It provided tunable phase range of 350° over the frequency range of 353.5-359.3 GHz at 40 V, where a maximum phase shift 362.6° was achieved at 357 GHz. The LC dielectric constant was obtained by fitting the computed reflectance spectrum to the measured result. We compared accurate model, considering both inhomogeneity and anisotropy of the liquid crystal, with the simplified model. In addition, the differences were analysed between the measurements, accurate and conventional model. The results show the liquid crystal phase shifter is great for beam scanning antenna array in THz. [ABSTRACT FROM AUTHOR]

Light-emitting liquid crystal displays (LE-LCDs), serving as emissive displays, are considered as promising alternatives to conventional LCDs because of their superior power efficiency. A dichroic fluorescent dye (Z)-2-(4-aminophenyl)-3-(4-(fluorophenyl)acrylonitrile (CN-AFAN) is synthesised, which exhibits strong fluorescence in the solution and solid states. Moreover, an electrically switchable optical switch based on CN-AFAN and a cholesteric liquid crystal is demonstrated, which combines the internal scattering of excitation light and the dichroism of CN-AFAN to improve fluorescence contrast. The photoluminescence and transmittance of the optical switch is modulated by an electric field between the planar state, focal conic state, and homeotropic state. The resultant device is cost-effective and easy to fabricate, thereby demonstrating immense potential for security and display applications. [ABSTRACT FROM AUTHOR]

This paper presents a solid-state volumetric 3-D display system utilizing 20 LC light shutters as a display module, which provides viewers with true depth cues. The electro-optic properties of light shutters based on normal-mode PSCT were investigated. The device shows a field-on transmittance of 86.2%. When applied an operation voltage of 100 V at 28 °C, the response time is 540 μs for switching-on and 180 μs for switching-off, which is suitable for the solid-state volumetric 3-D display. The stability, reliability, and repeatability of the device have also been characterized. [ABSTRACT FROM PUBLISHER]

A bis(2-oxoindolin-3-ylidene)-benzodifuran-dione (BIBDF)-based low band gap polymer (PBIBDF-BT), containing a solubilizing alkyl chain bithiophene unit as a donor, has been synthesized. The polymer with a low-lying LUMO/HOMO energy level (--4.03/--5.55 eV) exhibits efficient ambipolar charge transport. The electron and hole mobilities are as high as 1.08 and 0.30 cm² V-1 s-1 respectively. [ABSTRACT FROM AUTHOR]

To meet the requirements for rapid tumor growth, a complex array of non-neoplastic cells are recruited to the tumor microenvironment. These cells facilitate tumor development by providing matrices, cytokines, growth factors, as well as vascular networks for nutrient and waste exchange, however their precise origins remain unclear. Through multicolored tissue transplant procedures; we have quantitatively determined the contribution of bone marrow-derived and adiposederived cells to stromal populations within syngeneic ovarian and breast murine tumors. Our results indicate that subpopulations of tumor-associated fibroblasts (TAFs) are recruited from two distinct sources. The majority of fibroblast specific protein (FSP) positive and fibroblast activation protein (FAP) positive TAFs originate from mesenchymal stem/ stromal cells (MSC) located in bone marrow sources, whereas most vascular and fibrovascular stroma (pericytes, α-SMA+ myofibroblasts, and endothelial cells) originates from neighboring adipose tissue. These results highlight the capacity for tumors to utilize multiple sources of structural cells in a systematic and discriminative manner. [ABSTRACT FROM AUTHOR]

Analysis of accommodation space variation during deposition of the Cretaceous Qingshankou Formation in the Songliao Basin, NE China, indicates that accommodation space changed both through time and across the basin as a seesaw movement. The mid-upper Qingshankou Formation is divided into three units. In each unit, changes of accommodation space differ in the southern and northern part of the basin. Increasing accommodation in the southern part is accompanied by a decrease in the northern part, and vice versa. Between the northern and southern basin, there was a neutral belt that is like a fulcrum, called the transformation belt here, where the accommodation did not change to any significant degree. We call this response ‘accommodation transformation’, whose characteristics are defined by tectonic subsidence analysis, palaeontological and sedimentary analyses. The accommodation increasing belt, decreasing belt, transformation belt and accommodation transformation boundary together constitute the accommodation transformation system. The recognition of accommodation transformation in the Songliao Basin provides a new insight into sequence stratigraphy and might be widely applicable. [ABSTRACT FROM AUTHOR]

We have shown that the lateral correlation length of dielectric roughness strongly affects the molecular and mesoscale structures and charge transport properties of pentacene. Two series of dielectric surfaces with different lateral characteristics were prepared by a multilayer crosslinking polystyrene (MCPS) method and a plasma etching method. The MCPS surfaces consisted of spike-like structures with dimension of several hundred nanometers, whereas the plasma etched surfaces exhibited bumpy structures with a size about ten times smaller. For both methods, the increase of surface roughness tended to disturb the molecular and mesoscale ordering of pentacene films and reduced their charge carrier mobility. However, the performances of the devices prepared by the plasma etching methods showed a much stronger dependence on the surface roughness than those of the MCPS samples. The average mobilities on the MCPS samples with root mean squar roughness of 3.97 nm were 342 times higher than those on the plasma etching surface with similar roughness values. These results suggested that optimizing the nanostructural surfaces of dielectrics presented an effective approach to improve device performance. [ABSTRACT FROM AUTHOR]