查找使用阿拉丁产品的科研文献

Er-doped titanium dioxide/silicon dioxide fibres with enhanced photodegradation performance

Jidong Wang,Xiaolong An,Yuan Yu,Xiaoqiang Li,Mingqiao Ge

In this work, an erbium-doped titanium dioxide/silicon dioxide (Er@TS) fibrous composite was fabricated by a combination of sol–gel process, electrospinning and calcination. The precursor sol was prepared from one-pot condensation of Er trioxide, tetraethyl orthosilicate and titanium n-butoxide in the mixture of nitric acid solution (pH = 2.0) and ethyl alcohol. After the addition of poly(vinylpyrrolidone), the precursor of fibrous membrane was fabricated by electrospinning, followed by calcination to form the Er@TS composite. The physicochemical properties of fibrous membranes, both of before and after calcination, were characterised. The earth rare element Er is aiming to enhance the overall photodegradation capability of nanofibrous composite. The results of photodegradation tests demonstrated that the Er@TS composite exhibit enhanced photocatalytic activity for degradation of methyl orange.

Syntheses, Structures, Physical Properties, and Electronic Structures of Ba2MLnTe5 (M = Ga and Ln = Sm, Gd, Dy, Er, Y; M = In and Ln = Ce, Nd, Sm, Gd, Dy, Er, Y)

Wenlong Yin,Wendong Wang,Lei Bai,Kai Feng,Youguo Shi,Wenyu Hao,Jiyong Yao,Yicheng Wu

The 12 new rare-earth tellurides Ba2MLnTe5 (M = Ga and Ln = Sm, Gd, Dy, Er, Y; M = In and Ln = Ce, Nd, Sm, Gd, Dy, Er, Y) have been synthesized by solid-state reactions. The two compounds Ba2GaLnTe5 (Ln = Sm, Gd) are isostructural and crystallize in the centrosymmetric space group P1̅, while the other 10 compounds belong to another structure type in the noncentrosymmetric space group Cmc21. In both structure types, there are one-dimensional anionic 1∞[MLnTe5]4– chains built from LnTe6 octahedra and MTe4 (M = Ga, In) tetrahedra, but the connectivity between the LnTe6 octahedra and MTe4 tetrahedra is different for the two structure types. On the basis of the diffuse-reflectance spectra, the band gaps are around 1.1–1.3 eV for these compounds. The Ba2MLnTe5 (M = Ga and Ln = Gd, Dy; M = In and Ln = Gd, Dy, Er) compounds are paramagnetic and obey the Curie–Weiss law, while the magnetic susceptibility of Ba2InSmTe5 deviates from the Curie–Weiss law. In addition, electronic structure calculation on Ba2MYTe5 (M = Ga, In) indicates that they are both direct-gap semiconductors with large nonlinear-optical coefficients.

In vitro and in vivo assay of the ER lipid scramblase TMEM41B

Lingzhi Wu,Lu Liu,Bolin Xu,Dong Huang,Xiao-Wei Chen

Summary Amphipathic phospholipids translocated by scramblases play a central role in facilitating lipid movement across the membrane bilayer, especially at the endoplasmic reticulum (ER) membranes. Here, we present a protocol for assessing the activity of the ER-localized lipid scramblase TMEM41B. We detail an in vitro fluorescent liposome-based phospholipid scrambling assay and in vivo metabolic labeling in living cells using alkyne-choline. The scramblase activity of other VTT (VMP1, TMEM41, and Tvp38) domain-containing proteins, such as TMEM41A and VMP1, can be assayed. For complete details on the use and execution of this protocol, please refer to Huang et al. (2021) .

Nanoplate-Assembled Yb/Er-BiOBr Microspheres for Durable Self-Cleaning Photocatalytic Coatings

Yan Xiangyang,Li Ningning,Li Maoyi,Fan Kaixuan,Xia Huiyun

This study addresses the efficient and safe purification of low-concentration atmospheric NO. A Yb/Er-codoped nanostructured BiOBr was synthesized via a solvothermal method, and a composite superhydrophobic coating (FSBE) was fabricated by a layer-by-layer spraying strategy using epoxy resin, nano-SiO 2 , and perfluoroalkyltrimethoxysilane, achieving integrated high photocatalytic activity and excellent micronano-structured superhydrophobicity. The Yb/Er codoping successfully modulates the original layered BiOBr into spherical hollow microspheres assembled from interconnected nanoplates with an optimal Yb/Er ratio of 10:1. This modification enlarges the specific surface area by approximately 7 times, broadens the light response range, and effectively restrains the recombination of photogenerated carriers. The constructed FSBE coating possesses a micronano rough surface with water and ethylene glycol contact angles above 150 ° , demonstrating superior self-cleaning performance. Under visible light and full-spectrum irradiation, the FSBE coating delivers NO degradation efficiencies of 62.0 and 78.4%, which are 2.85-fold and 1.5-fold higher than those of pure BiOBr, respectively, while efficiently suppressing NO 2 accumulation. The coating maintains a photocatalytic efficiency of 65.8% after five cycling tests and exhibits excellent mechanical abrasion resistance and chemical stability. The synergistic effect between the superhydrophobic self-cleaning structure and nanoscale rare-earth-doping-enhanced photocatalysis accounts for its durable NO purification capability. This work provides an insight into the design of high-performance and long-lived photocatalytic nanocoatings for atmospheric environmental remediation.

ER-tethering directs TREX1 penetration of a BAF-dependent barrier at micronuclei

Yanyang Chen,Roshan Xavier Norman,Eléonore Toufektchan,Xiaohan Luan,Abraham Shim,Hannah Rosenberg,Marton Tibor Kovacs,Ashley Nichols,James Hickling,Paolo Cifani,Alex Kentsis,Wen Zhou,John Maciejowski

Micronuclei are membrane-encapsulated nuclear aberrations that form following chromosome segregation errors. Micronuclear membrane collapse permits access of the pattern recognition receptor cGAS and its antagonist, the TREX1 exonuclease. TREX1 endoplasmic reticulum tethering is essential for invasion into ruptured micronuclei, but the mechanisms underlying this dependency are unknown. Here, we identify BAF as a key regulator of TREX1 activity at micronuclei. BAF accumulates at micronuclei following membrane collapse and augments TREX1 recruitment via interactions with LEM-domain proteins. Despite delayed entry, TREX1 exhibits enhanced micronuclear DNA degradation and independence from ER-tethering in BAF-deficient cells. Recombinant BAF inhibits TREX1-mediated DNA degradation in vitro via DNA-binding. BAF similarly outcompetes cGAS for micronuclear DNA and limits cGAS-dependent immune signaling. These findings reveal a BAF-dependent protective barrier to the diffusive entry of DNA-binding proteins into ruptured micronuclei that explains TREX1 ER-tethering requirements for suppressing innate immune responses in chromosomally unstable cells.

Internal OH− defect-induced upconversion quenching in β-NaLuF4:Yb,Er microcrystals

Yue Wang,Yaomin Lei,Wuqin Chen,Ruian Yang,Xinyang Gu,Gaofeng Pan,Xuesong Zhai,Jinshan Wang

Luminescence quenching effect of lanthanide-doped upconversion materials occurs with high probability even in larger-sized particles, but their main quenching pathway remains controversial. In this work, we investigate the influence of the surfactant and pH value on the luminescence properties of β-NaLuF 4 :Yb,Er microcrystals. A convincing evidence can be provided by the combination of X-ray diffraction (XRD), inductively coupled plasma (ICP) spectrometer, and Eu 3+ structural probe measurements that the major quenching pathway comes from the fast energy migration from the excited lanthanides to nearby OH − defects in the crystal lattice rather than surface quenching effect. Even at OH − -rich reactant condition, the upconversion luminescence intensity becomes more efficient by reduced internal quenching effects. Our findings provide a new and fundamental understanding of severe luminescence quenching effect at microscale, thus guiding the design and preparation of highly efficient upconversion materials.

NiPS3 nanosheets for passive pulse generation in an Er-doped fiber laser

Jin Wang,Tao Wang,Xinyao Shi,Jian Wu,Yijun Xu,Xianguang Ding,Qiang Yu,Kai Zhang,Pu Zhou,Zongfu Jiang

With the rapidly increasing demands of industrial material processing, biomedical sensing, light detection, and high-speed communication, various novel two-dimensional (2D) materials have been synthesized and employed in ultrafast fiber laser generation due to their advantages of easy processing characteristics, desirable structures and excellent nonlinear optical properties. However, finding an efficient 2D material-based saturable absorber (SA) with the capacity of both high stability and excellent working property performance remains a challenge. Herein, high-quality NiPS3 crystals, from the metal phosphorus trichalcogenide (MPT3) family, were synthesized by a modified chemical vapor transport (CVT) method and a few-layer NiPS3 nanosheet SA was easily obtained using a direct liquid-phase exfoliation method. Different from other 2D materials, ultrathin NiPS3 nanosheets display a good stability. Moreover, a passively Q-switched operation and dual-wavelength mode-locked pulse output were proposed based on a NiPS3-SA erbium-doped fiber (EDF) laser. In the passively Q-switched operation, the maximum peak power was 6.40 mW with a maximum pulse energy of 29.66 nJ. It is also worth noting that dual-wavelength pulse output was achieved in passively mode-locked pulse generation. These results not only supply other choices of SAs for pulse generation, but also provide guidance to extend other possible applications of the MPT3 family for nonlinear optics.

Er-doped silicate fiber amplifiers in the L-band with flat gain

Yan Sun,Xin Wang,Qiubai Yang,Yafei Wang,Fan Wang,Lili Hu,Lili Hu,Lili Hu,Chunlei Yu,Chunlei Yu,Meisong Liao,Shubin Chen

Electrospinning preparation and white upconversion luminescence of Y2Ti2O7:Tm/Yb/Er nanotubes

Han Zhanwen,Yu Hongquan,Tian Zhuang,Zhang Jinsu,Sun Jiashi,Li Xiangping,Xu Sai,Chen Baojiu

The lanthanide-based white light-emitting diodes excited by irradiation at a wavelength of 980 nm have attracted increasing attention because of their low photon frequency and ease of implementation. Here, we report on warm, white, Y 2 Ti 2 O 7 :Tm/Yb/Er nanotubes prepared by a simple single-needle electrospinning method. The Y 2 Ti 2 O 7 :Tm/Yb/Er nanotubes have an outer diameter of about 180 nm, and a wall thickness of 36 nm. Their color coordinates and chromaticity were controlled to yellow → red → warm white by adjusting the Tm 3+ concentration from 0.5 to 2.0%. The luminescence properties and upconversion mechanism of Y 2 Ti 2 O 7 :Tm/Yb/Er nanotubes were investigated. The warm white Y 2 Ti 2 O 7 :Tm/Yb/Er nanotubes exhibit a strong correlated color temperature to a household incandescent lamp.

Solvothermal synthesis and upconversion luminescence of ultra-small Sc2O3: Yb, Er nanoparticles

Huilian Qin,Jing Li,Meijuan Yuan,Yaru Peng,Yuxin Huang,Li Chen

Monodisperse sub-10 nm Sc 2 O 3 : Yb, Er upconverting nanoparticles (UCNPs) were firstly synthesized via solvothermal method in three-neck round-bottom flask. The X-ray diffraction (XRD) shows that the prepared UCNPs possess cubic structure. The transmission electron microscopy (TEM) shows that sample has monodisperse spheroid morphology with high crystallinity . The average size of spheroid UCNPs could be controllable manipulated as small as 3 nm. Furthermore, the sample exhibits stronger red and green upconversion luminescence (UCL) than reported Sc 2 O 3 : Yb, Er nanostructure by biphasic solvothermal method. The Fourier-transform infrared (FTIR) spectra and decay curve reveal that ultra-small Sc 2 O 3 : Yb, Er UCNPs exhibit the reduced surface groups and long decay time of Er 3+ ions. The results indicate Sc 2 O 3 : Yb, Er UCNPs is a probable oxide material with small size and intense UCL for biological applications.

Absorption of caffeine in fermented Pu-er tea is inhibited in mice

Ye-wei Huang,Huan-huan Xu,Su-min Wang,Yi Zhao,Yu-min Huang,Run-bo Li,Xuan-jun Wang,Shu-mei Hao,Jun Sheng

Caffeine is present in a number of dietary sources consumed worldwide. Although its pharmacokinetics has been intensively explored, little is known about complexed caffeine (C-CAF) in aqueous extraction of fermented Pu-er tea. The major components of C-CAF are oxidative tea polyphenols (OTP) and caffeine. Furthermore, the C-CAF can be precipitated in low pH solution. After administering the same amount of total caffeine and comparing the peak level of plasma caffeine with the coffee (contains 0.11 ± 0.01% C-CAF) group, the results showed that the caffeine/OTP (contains 66.67 ± 0.02% C-CAF) group and the instant Pu-er tea (contains 23.18 ± 0.02% C-CAF) group were 33.39% and 25.86% lower, respectively. The concentration of the metabolites of caffeine supports the idea that the absorption of the C-CAF was inhibited in mice. Congruent with this result, the amount of caffeine detected in mice excrement showed that more caffeine was eliminated in the caffeine/OTP group and the Pu-er tea group. The locomotor activity tests of mice demonstrated that the stimulating effect of caffeine in caffeine/OTP and Pu-er tea was weaker than in coffee. Our findings demonstrate that caffeine can be combined with OTP and the absorption of C-CAF is inhibited in mice, thus decreasing the irritation effect of caffeine. This may also be developed as a slow release formulation of caffeine.

High Response Gas Sensors for Formaldehyde Based on Er-doped In2O3 Nanotubes

Xuesong Wang,Jinbao Zhang,Lianyuan Wang,Shouchun Li,Li Liu,Chang Su,Lili Liu

Pure and Er-doped In 2 O 3 nanotubes were systematically fabricated by using a single nozzle eletrospinning method followed by calcination . The as-synthesized nanotubes were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectrometry and X-ray powder diffraction (XRD). Compared with pure In 2 O 3 nanotubes, Er-doped In 2 O 3 nanotubes exhibit improved formaldehyde sensing properties at 260 °C. The response of Er-doped In 2 O 3 nanotubes to 20 ppm formaldehyde is about 12, which is 4 times larger than that of pure In 2 O 3 nanotubes. The response and recovery times of Er-doped In 2 O 3 nanotubes to 20 ppm formaldehyde are about 5 and 38 s, respectively. Furthermore, the response of Er-doped In 2 O 3 nanotubes to 100 ppb formaldehyde is 2.19.