Publications by authors named "Shen Xiong"

Due to intrinsic defects in blue-light-emitting perovskite materials, the charge carriers are prone to being trapped by the trap states. Therefore, the preparation of efficient blue-light-emitting perovskite materials remains a significant challenge. Herein, CsPb(Cl/Br) nanocrystal (NCs)@SiO structures were fabricated through hydrolyzing (3-aminopropyl)-triethoxysilane (APTS).

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Fourier Transform Mid-Infrared Spectroscopy (FT-MIRS) can be used for quantitative detection of milk components. Here, milk samples of 458 Chinese Holstein cows from 11 provinces in China were collected and we established a total of 22 quantitative prediction models in milk fatty acids by FT-MIRS. The coefficient of determination of the validation set ranged from 0.

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CsPbBr/SiO heterostructures were synthesized by the hydrolysis reaction of a mixture of CsPbBr nanocrystals (NCs) and (3-aminopropyl)triethoxysilane (APTS) in air. Compared with CsPbBr NCs, the CsPbBr/SiO heterostructures exhibit stronger photoluminescence (PL) intensity, longer lifetime of PL (∼40.5 ns), and higher PL-quantum yield (PLQY, ∼86%).

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Self-referenced spectral interferometry with extended time excursion (SRSI-ETE) is a powerful method for single-shot characterization of the temporal contrast of a high peak power laser, which has high temporal resolution but a low dynamic range. Here, a temporal contrast reduction method is proposed that uses the cascaded Kerr lens process in two thin glass plates. Combined with the SRSI-ETE method, the measurement dynamic range of the method is increased about two orders of magnitude while having a 20 fs temporal resolution and a 40 ps time window in single shot.

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The roles of oxygen vacancies to enhance the electrochemical performance were not clearly explained in comprehensive research. Herein, the vertically oriented NiCoS/MnO core-shell nanocomposites are in situ grown on the nickel foam (NF) surface and activated by oxygen vacancy engineering via a chemical reduction method. The scanning electron microscope (SEM) and transmission electron microscope (TEM) results show the shell-MnO is well coated on the core-NiCoS.

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With the exponential growth of multi-omics data, its integration and utilization have brought unprecedented opportunities for the interpretation of gene regulation mechanisms and the comprehensive analyses of biological systems. IAnimal (https://ianimal.pro/), a cross-species, multi-omics knowledgebase, was developed to improve the utilization of massive public data and simplify the integration of multi-omics information to mine the genetic mechanisms of objective traits.

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Mesenchymal stromal cells (MSCs) play an important role in the development of human cancer. Meanwhile, exosomes released by MSCs can mediate cell-cell communication by delivering microRNAs (miRNAs/miRs). Hence, this study aimed to explore the role of bone marrow mesenchymal stromal cell (BMSC)-derived exosomal miR-551b-3p in breast cancer.

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The air distribution system in an airliner plays a key role in maintaining a comfortable and healthy environment in the aircraft cabin. To evaluate the performance of a novel displacement ventilation (DV) system and a traditional mixing ventilation (MV) system in an airliner cabin, this study conducted experiments and simulations in a seven-row cabin mockup. This investigation used ultrasonic anemometers and T-thermocouples to measure the air velocity, temperature and distribution of 1 μm and 5 μm particles.

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Spatiotemporal optical vortex (STOV) light is a new type of vortex light with transverse orbital angular momentum (OAM) which is different from conventional spatial vortex light. Understanding the properties of STOV are meaningful before STOV are applied. We present a theoretical study on the generation and propagation of spatiotemporal vortices step by step based on diffraction theory.

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A single-shot fourth-order autocorrelator based on cross-polarized wave generation (XPW) is proposed for the temporal contrast measurement, where the XPW process has the advantages of higher energy conversion efficiency, more compact setup, and less sensitivity to misalignment in comparison to the self-diffraction process. The measurement dynamic of 10 is obtained with only 6 mJ input laser pulse, where the input beam for XPW is focused by a cylindrical lens and XPW signal with the energy of 400 µJ and time duration of 27.2 fs is obtained.

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High-energy tens (10s) to hundreds (100s) petawatt (PW) lasers are key tools for exploring frontier fundamental researches such as strong-field quantum electrodynamics (QED), and the generation of positron-electron pair from vacuum. Recently, pulse compressor became the main obstacle on achieving higher peak power due to the limitation of damage threshold and size of diffraction gratings. Here, we propose a feasible multistep pulse compressor (MPC) to increase the maximum bearable input and output pulse energies through modifying their spatiotemporal properties.

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The indoor environment influences occupants' health. From March 1, 2018, to February 28, 2019, we continuously monitored indoor temperature (T), relative humidity (RH), and CO concentration in bedrooms via an online system in 165 residences that covered all five climate zones of China. Meanwhile, we asked one specific occupant in each home to complete questionnaires about perceived air quality and sick building syndrome (SBS) symptoms at the end of each month.

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One of the most significant bottlenecks in achieving kilojoule-level high-energy petawatt (PW) to hundreds-petawatt (100PW) lasers is the requirement of as large as meter-sized gratings so as to avoid the laser-induced damage in the compressor. High-quality meter-sized gratings have so far been difficult to manufacture. This paper proposes a new in-house (intra-) beam-splitting compressor based on the property that the damage threshold of gratings depends on the pulse duration.

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Novel multicolor concentric annular ultrafast vector beams (MUCAU-VB) are firstly generated simply by using cascaded four-wave mixing (CFWM) in a glass plate pumped by two intense vector femtosecond pulses. A proof-of-principle experiment shows that up to 10 frequency up-conversion concentric annular radially polarized sidebands are obtained simultaneously based on CFWM process, where the spectra range of the first 7 order sidebands extending from 545 nm to 725 nm. The results prove the polarization transfer property from the pump beam to the signal beams even in the CFWM, a third-order optical parametric process.

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As the first step in a 100 petawatt (PW) laser facility, seed pulses with high performance are important to guarantee the quality of the output laser pulse. Here we propose a novel method based on a single-stage four-wave mixing process for the generation of seed pulses with a smooth and broadband spectrum, high energy, and high temporal contrast (TC). As high as 250 μJ pulses at approximately 910 nm central wavelength with a high TC and broader than 200 nm bandwidth are obtained in a piece of transparent medium directly after a commercial Ti:sapphire amplifier.

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The ventilation modalities in most Chinese residences are infiltration and opening windows. We measured infiltration rates and air change rates at night, with no attempt to change occupants' behaviors, of urban residences in five climate zones of China during four seasons. Using the CO decay method, we found the median infiltration rate for 294 residences to be 0.

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A single-shot characterization of the temporal contrast of a petawatt laser pulse with a high dynamic-range, is important not only for improving conditions of the petawatt laser facility itself, but also for various high-intensity laser physics experiments, which is still a difficult problem. In this study, a new idea for improving the dynamic-range of a single-shot temporal contrast measurement using novel temporal contrast reduction techniques is proposed. The proof-of-principle experiments applying single stage of pulse stretching, anti-saturated absorption, or optical Kerr effect successfully reduce the temporal contrast by approximately one order of magnitude.

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We demonstrate the generation of 100-μJ-level multicolored femtosecond pulses based on a single-stage cascaded four-wave mixing (CFWM) process in a thin glass plate by using cylinder lenses. The generated high-energy CFWM signals can shift the central wavelength and have well-enhanced temporal contrast because of the third-order nonlinear process. They are innovatively used as clean sampling pulses of a cross-correlator for single-shot temporal contrast measurement.

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A compact and alignment-free device based on transient grating self-referenced spectral interferometry is proposed to realize the temporal profile measurement of femtosecond laser pulses. The entire optical setup is composed of two lenses and two glass plates on a straight line with tubes, thereby avoiding complicated optical alignment and improving the stability and practicality of the device. Two 51.

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An efficient method for the determination of eight parabens in human breast tumor (n = 102) and peripheral adipose tissue samples (n = 87) was successfully developed. After a precipitation procedure (acetonitrile-water-15% (w/v) zinc sulfate solution) was applied to finely-chopped tissue samples, ultrasound-assisted dispersive liquid-liquid microextraction was conducted on the sample solution. The extracted parabens were determined by gas chromatography-mass spectrometry.

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A simple and sensitive method for the simultaneous determination of eight parabens in human plasma and urine samples was developed. The samples were preconcentrated using dispersive liquid-liquid microextraction based on the solidification of floating organic drops and determined by high-performance liquid chromatography with ultraviolet detection. The influence of variables affecting the extraction efficiency was investigated and optimized using Placket-Burman design and Box-Behnken design.

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The self-referenced spectral interferometry (SRSI) technique, which is usually used for microjoule-level femtosecond pulse characterization, is improved to characterize weak femtosecond pulses with nanojoule based on the transient-grating effect. Both femtosecond pulses from an amplifier with 3 nJ per pulse at 1 kHz repetition rates and femtosecond pulses from an oscillator with less than 0.5 nJ per pulse at 84 MHz repetition rates are successfully characterized.

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Objective: To investigate the feasibility and clinical characteristics of small partial laryngectomy without tracheotomy for T1-2 stage glottic carcinoma.

Method: Forty-five patients with laryngeal squamaous cell carcinoma in T1-2 stage received small partial laryngectomy without tracheotomy.

Result: All patients were primarily healed and were hospitalized for an average of 11.

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The rapid prediction of the low-carbon fatty acids (C < or = 14) content in grease samples was achieved by a mathematical model established by near infrared spectroscopy combined with support vector machine regression (SVR). In the present project, near-infrared spectrometer SupNIR-5700 was used to collect near-infrared spectra of 58 samples; partial least square (PLS) was applied to remove the strange samples, and principal component analysis (PCA) was conducted on the measurements; radial basis function (RBF) kernel function was selected to establish a regression model supporting vector machine, and then detailed analysis and discussions were conducted concerning their spectral preprocessing and parameters optimization methods. Experimental results showed that by applying particle swarm optimization (PSO) the model demonstrated improved performance, stronger generalization ability, better prediction accuracy and robustness.

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