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A new design of a bio-random laser based on a butterfly wing structure and ITO glass is proposed in this article. Firstly, the butterfly wing structure was integrated in a liquid crystal cell made of ITO glass. The integrated liquid crystal cell was injected with liquid crystal and dye to obtain a bio-random laser. A non-biological random laser was obtained with a capillary glass tube, liquid crystal and dye. The excitation spectra and thresholds were recorded to evaluate the performance of the biological and non-biological random lasers. The results show that the excitation performance stability of the bio-random laser is improved and the number of spikes in the spectra is reduced compared with the non-biological random laser. Finally, the equivalent cavity length of the biological and non-biological random lasers was compared and the optical field distribution inside the butterfly wing structure was analyzed. The data show that the improvement of the excitation performance stability of the bio-random laser is related to the localization of the optical field induced by the photonic crystal structure in the butterfly wing.

Perovskite quantum dots are emerging as functional materials for modern optics and optoelectronics due to their superior optical properties and easy integration. In this work, we demonstrated novel...

Continuous-wave (CW) operated laser is a key component for photonic chips. It has been highly desired to develop low-threshold, high-efficiency, long-term operational, low-cost and easily integratable CW laser. As excellent optical gain materials, quantum dots (QDs) have been intensively investigated for on-chip CW lasers owing to their high photoluminescence quantum yields, tunable emission wavelengths and easy integration. Base on the difference of preparation processes, QDs can be classified into epitaxial QDs and solution-processed colloidal QDs (CQDs). In this mini-review, we summarize the research progresses of epitaxial III–V semiconductor QD and solution-processed CQD-based CW lasers. The challenges associated with the realization of CQD CW lasers are discussed in detail. In particular, the emerging perovskite-based CW lasers are highlighted. Finally, a short perspective of QD-based CW lasers is presented.

Room-temperature-operated continuous-wave lasers have been intensively pursed in the field of on-chip photonics. The realization of a continuous-wave laser strongly relies on the development of gain materials. To date, there is still a huge gap between the current gain materials and commercial requirements. In this work, we demonstrate continuous-wave lasers at room temperature using rationally designed in situ fabricated perovskite quantum dots in polyacrylonitrile films on a distributed feedback cavity. The achieved threshold values are 15, 24, and 58 W/cm2 for green, red, and blue lasers, respectively, which are one order lower than the reported values for the conventional CdSe quantum dot-based continuous-wave laser. Except for the high photoluminescence quantum yields, smooth surface, and high thermal conductivity of the resulting films, the key success of an ultralow laser threshold can be explained by the interaction of polyacrylonitrile and perovskite induced “charge spatial separation” effects. This progress opens up a door to achieve on-chip continuous-wave lasers for photonic applications.

As large storage tank has large diameter, the acoustic emission (AE) wave attenuation will increase. The number of location events may be lost. The activity of the defect cannot be understood. Reliability of safety assessment of tank bottom corrosion will be affected. In order to solve the problem, an acoustic source identification method is presented. Based on the AE source location theory of tank bottom, it is put forward that the sensors located on the tank bottom medium are employed together with the sensors arranged on tank outside wall near tank bottom to identify the acoustic source of tank bottom corrosion defects. Experiments of acoustic source location and identification for simulative tank bottom corrosion have been conducted. The results show that the method can help for recognizing acoustic source in arbitrary triangle and area location of tank bottom area; in addition, the sensor inside the tank is more sensitive to the identification of corrosion acoustic source than the external sensor. Therefore, the method can improve the reliability of results for the identification and location of tank bottom acoustic source.

A wideband butterfly antenna based on deep learning parameter optimization algorithm is proposed in this paper. Two neural networks are designed to model the mapping relationship of structure parameters to frequency response and frequency response to structure parameters respectively. The parameter optimization algorithm proposed consists of two stages: training NN1 and optimizing parameters using NN2. A wideband butterfly antenna is designed to verify the algorithm. The experiment shows that the structure parameter optimization algorithm proposed can quickly optimize the structure parameters of antenna with the best preformance and save a lot of manpower and time cost.

Purpose Measurement uncertainty calculation is an important and complicated problem in digitised components inspection. In such inspections, a coordinate measuring machine (CMM) and laser scanner are usually used to get the surface point clouds of the component in different postures. Then, the point clouds are registered to construct fully connected point clouds of the component’s surfaces. However, in most cases, the measurement uncertainty is difficult to estimate after the scanned point cloud has been registered. This paper aims to propose a simplified method for calculating the uncertainty of point cloud measurements based on spatial feature registration. Design/methodology/approach In the proposed method, algorithmic models are used to calculate the point cloud measurement uncertainty based on noncontact measurements of the planes, lines and points of the component and spatial feature registration. Findings The measurement uncertainty based on spatial feature registration is related to the mutual position of registration features and the number of sensor commutation in the scanning process, but not to the spatial distribution of the measured feature. The results of experiments conducted verify the efficacy of the proposed method. Originality/value The proposed method provides an efficient algorithm for calculating the measurement uncertainty of registration point clouds based on part features, and therefore has important theoretical and practical significance in digitised components inspection.

Selenocysteine (Sec), which is a biological selenol incorporated into selenoproteins specifically, plays vital roles in physiological processes and cancer treatment. However, there are limited fluorescent probes for selective detection of Sec and in only one case is a near-infrared (IR) fluorescent probe applied in biological imaging of Sec in living animals. In this work, we have synthesized a new fluorophore, boron-dibenzopyrromethene (B-Bodipy), with an absorption maximum at 650–660 nm, and constructed two deep red fluorescent probes, Sel-p1 and Sel-p2, which are two ethers composed of a 2,4-dinitrobenzenoxy and B-Bodipy moiety. Experiments in solution show that the two probes can react effectively with selenols to release the fluorophore via aromatic nucleophilic substitution (SNAr), with a low limit of detection (16 nM and 9 nM), high selectivity and excellent photostability. The potential application for the detection of Sec in cells has been demonstrated by cell imaging experiments of Sel-p2, including detection of exogenous Sec and selenite-induced Sec in living cells. Furthermore, Sel-p2 as a red fluorescent probe can achieve the detection of Sec in animals by mice imaging experiments.

The aim of the study was to investigate the effects of recombinant human growth hormone on protein malnutrition and insulin-like growth factor-1 (IGF-1) and interleukin-2 (IL-2) gene expressions in chronic nephrotic syndrome. Eighty patients with chronic nephrotic syndrome were admitted to our hospital. The patients were included in the study period from January 2015 to December 2016 and were divided into two groups (40 cases in each group) according to the random number method. All the patients enrolled received symptomatic and supportive treatment. The observation group was injected subcutaneously with recombinant human growth hormone, while the control group was treated with Shenyankangfu tablets. The recovery time of the clinical symptoms, change in serum protein, caloric intake and protein metabolism after intervention were compared between the two groups. Changes in serum cystatin C, IGF-1 and IL-2 before intervention, and at 1 week, 1 month and 3 months after intervention were detected, and the adverse reactions in the two groups were observed during the treatment. After intervention, the improvement time of proteinuria, hypoproteinemia, edema and hyperlipidemia in the observation group was significantly shorter than that in the control group (P

Nitric oxide (NO) is an important signaling molecule involved in many physiological and pathological processes. To understand these NO-mediated processes, it is a key to develop rapid and specific detection methods for NO. In the past 2 decades, numerous excellent fluorescent probes for NO have been designed; however, it still remains limitations such as slow response, low selectivity, and short excitation wavelength (600 nm). In this Article, a two-photon fluorescent probe, NO-QA5, has been developed with 3-dimethylaminophenyl linking at the 6-position of 5-aminoquinoline as both the active site and prefluorophore for detection of NO. The nonfluorescent NO-QA5 can fast react with NO via a diazonium intermediate to generate two azoic regioisomers, one of which exhibits intramolecular charge transfer (ICT) emission, and two-photon absorption behavior (δΦ = 57 GM), giving a turn-on fluorescence rapid response. The sensing reaction is pH-insensitive in the range of 6-11 and highly selective and well sensitive (LOD = 15 nM), possible undergoing the same intermediate diazonium with the reaction under diazotization condition (NaNO

A new series of donor-acceptor-π-linker-acceptor (D–A–π–A) featured organic dyes containing Bodipy derivative as the auxiliary acceptor, furan unit as the π conjugated spacer, and 2-cyanoacrylic acid as the anchor group were synthesized and applied in dye-sensitized solar cells (DSSCs). The incorporated electron-withdrawing unit of Bodipy enhances light harvesting by decreasing the molecular energy gap and red-shifting absorption spectra. For comparison, three different arylamine chromophores namely 3-methoxy-9 H -carbazole ( CBZ-B ), triphenylamine ( TPA-B ) and phenoxazine ( POZ-B ) were separately appended onto the 6-position of Bodipy unit to study the effect of the electron donating groups on device performance. The UV–vis absorption spectra, electrochemical properties, density functional theory calculation, photovoltaic properties and electrochemical impedance measurements of DSSCs with these three dyes were systematically investigated. The Bodipy dyes have broad absorption spectra covering the range of 250–700 nm with the highest molar extinction coefficient up to >55 000 M −1 cm −1 . The molecular energy level tuning can be conveniently accomplished by alternating the donor moiety. The DSSCs based on TPA-B showed the best photovoltaic performance: a maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 70%, a short-circuit photocurrent density ( J sc ) of 13.95 mA cm −2 , an open-circuit photovoltage ( V oc ) of 557 mV, and a fill factor ( ff ) of 0.61, corresponding to an overall conversion efficiency of 4.76% under standard global AM 1.5G solar light conditions. Our research demonstrates that Bodipy based D–A–π–A molecular architecture is a highly promising class for the improvement of the performance of DSSCs in the future.

Development of multi-input fluorescent probes would facilitate the monitoring of multiple biomolecular events leading to a common disease pathology. Here, we reported a two-input fluorescent probe (QME-N3) based on quinoline scaffold with two distinct reactive sites, the α,β-unsaturated carbonyl at 2-site and 6-azido group, which were specific acceptors of RSH and H2S respectively. The turn-on fluorescent probe could react with the two molecules via the Michael addition at the double bond for RSH and the reduction of the azide by H2S without mutual interference, to generate the intensively fluorescent product, which could act as a two-input AND logic gate. Furthermore, QME-N3 has very low cytotoxicity and excellent stability, and the resulting sensing product has a high two-photon absorption cross section. Consequently, detection of intracellular thiols and H2S can be achieved by cell fluorescence imaging under both one- and two-photon excitations.

Titanium nitride (TiN) is a promising plasmonic material with hard and abrasion-resistant specialities. In this study, a gain regime, namely, plasmon-enhanced random laser emission, is demonstrated in the Pyrromethene-597 (PM597) assisted by titanium nitride (TiN) film. For this, photoluminescence and random lasing are measured at different pumping energies from PM597/Silicon and PM597/TiN/Silicon samples. Enhanced lasing efficiency is observed in the PM597/TiN/silicon sample where a plasmon resonance is formed, which increases the energy transfer between TiN and PM597. Furthermore, the multiple scattering mediated by the TiN film also plays an important role for the lasing efficiency. It is worth mentioning that the random laser emission has a strong dependence on pump position. The study of the random laser from PM597/TiN/Silicon sample with film structure is aimed to obtain a good alternative (TiN) to replace noble metals at a lowest cost.