High sensitivity detection of trace impurities in the presence of other impurity species: The shallow thermal donors in Cz-Silicon

The combination of the techniques of Fourier transform spectroscopy (FTS) with the highly sensitive method of photothermal ionization spectroscopy (PTIS) opens up new possibilities for the investigation of trace impurities in semiconductors. The interpretation of the PTIS spectra when many donor species contribute to the photoconductivity is discussed with reference to the case of the shallow thermal donors in silicon.     

Pulsed laser induced absorption (one–four) dependence of electron mobility in CdI2 and ZnS crystals

The photoconductivity and electron mobility of CdI₂ and ZnS crystals have been studied using N₂-laser, fundamental and frequency doubled Nd:YAG laser. Low values of the electron mobilities obtained in the present case have been attributed to laser-induced-absorption. It is low in one photon excitation and increases with the order of absorption.     

Covalent Functionalization of Carbon Nanotube by Tetrasubtituted Amino Manganese Phthalocyanine

The multiwall carbon nanotube (MWCNT) bonded to 2, 9, 16, 23-tetraamino manganese phthalocyanine (TAMnPc) was obtained by covalent functionalization, and its chemical structure was characterized by TEM. The photoconductivity of single-layered photoreceptors, where MWCNT bonded by TAMnPc (MWCNT-b-TAMnPc) served as the charge generation material(CGM), was also studied.     

水相中POPs光化学降解研究进展

综述了近年来12种持久性有机污染物(POPs)在水体中光化学降解行为,从水体中POPs的光解途径、光解机理和定量结构-性质关系(QSPR)三个方面探讨了POPs在水体中的光化学行为,展望了水体中POPs光化学行为的研究前景.     

Optical Data Storage and Multicolor Emission Readout on Flexible Films Using Deep‐Trap Persistent Luminescence Materials

The fast‐growing amount of data that is produced every year creates an urgent need for ultracapacity storage media. However, 2D spatial resolution in the conventional optical data storage media has almost reached the limit. Further enlargement of storage capacity may rely on the development of the next‐generation data storage materials containing multiplexed information dimensions. Herein, a series of novel deep‐trap persistent luminescence materials (Sr_1‐xBa_x)Si₂O₂N₂:Eu/Yb,Dy with multicolor emissions in the whole visible region is developed and demonstrated a bit‐by‐bit optical data storage and readout strategy based on photon trapping and detrapping processes in these materials. Optical data can be handily encoded on a flexible film by a commercially available 405 nm laser and decoded by heating or by 980 nm laser scanning. The decoded information contains tunable spectral characteristics, which allows for the emission–intensity–multiplexing or emission–wavelength–multiplexing. The storage and readout strategy not only shows a great promise in the application of multidimensional rewritable optical data storage, but also opens new opportunities for advanced display technology and information security system.     

Cr3＋和Si4＋共掺对LiGa5O8近红外长余辉材料发光性能的影响

高温固相法合成了共掺Si⁴⁺的LiGa₅O ₈:Cr³⁺长余辉材料,采用X射线衍射、荧光光谱、余辉发射光 谱、余辉衰减曲线和热释光对样品分别进行了表征,并分析了Si掺杂对LiGa₅O₈:Cr 3+发光性能的影响。结 果表明,所合成的LiGa₅O₈:Cr³⁺,Si⁴⁺材料能产生近红外长余辉发射,主 发射峰位于717nm,归属于Cr³⁺的²E→⁴A 2 跃迁,共掺Si⁴⁺能显著提高余辉性能。掺杂浓度为0.25时,样 品的初始发光强度提高了3倍,余辉性能最佳, 余辉持续时间超过30 h。热释光曲线表明,共掺Si⁴⁺ 离子可增加有效陷阱数量,从而改善材料的余辉发光性能。     

Sustained Antitumor Immunity Based on Persistent Luminescence Nanoparticles for Cancer Immunotherapy

Immunotherapy holds great promise for cancer treatment. The key to improving the therapeutic effect is to drive the patient's own immune system to produce a strong, effective, and enduring tumor-specific immune response. Engineered nanoplatforms show promising potential in strengthening antitumor immune responses. However, current nanotherapeutic platforms based on exogenous responses stimulate the immune system only in a transitory and limited manner, which translates into insufficient immune activation and a low therapeutic efficacy. A novel targeted nano-immunostimulant (ZGS-Si-Pc@HA) is fabricated by coupling persistent luminescence nanoparticles with a photosensitizer and hyaluronic acid for sustained immune stimulation upon irradiation with biological window (659 nm) light. ZGS-Si-Pc@HA persistently drives reactive oxygen species production to induce immunogenic cell death, causing a durable tumor-specific immune response. Upon intratumoral injection, ZGS-Si-Pc@HA effectively alleviates immune tolerance and promotes T lymphocyte tumor infiltration. Further, ZGS-Si-Pc@HA enhances the therapeutic effect of checkpoint blockade immunotherapy, effectively inhibiting bilateral tumor growth and triggering an immunological memory effect. Nano-immunostimulants not only provide a new way to boost cancer immunotherapy, but also offer a reliable strategy for fighting cancer metastasis and recurrence clinically.     

pH Switchable Nanoplatform for In Vivo Persistent Luminescence Imaging and Precise Photothermal Therapy of Bacterial Infection

Photothermal therapy (PTT) is one of the most promising approaches to combat multidrug‐resistant bacteria with less potential to induce resistance and systemic toxicity. However, uncontrollable distribution of photothermal agents leads to lethal temperatures for normal cells, and failure to offer timely and effective antibacterial stewardship. A pH switchable nanoplatform for persistent luminescence imaging‐guided precise PTT to selectively destroy only pathological cells while protecting nearby normal cells in bacterial infected microenvironment is shown. The PLNP@PANI‐GCS is fabricated by grafting polyaniline (PANI) and glycol chitosan (GCS) onto the surface of persistent luminescence nanoparticles (PLNPs). It takes advantage of the long persistent luminescence of PLNPs to realize autofluorescence‐free imaging, the pH‐dependent light–heat conversion property of PANI to get a stronger photothermal effect at pH 6.5 than pH 7.4, and the pH environment responsive surface charge transition of GCS. Consequently, PLNP@PANI‐GCS enables effective response to bacterial‐infected acid region and electrostatic bonding to bacteria in vivo, ensuring the spatial accuracy of near‐infrared light irradiation and specific heating directly to bacteria. In vivo imaging‐guided PTT to bacterial infection abscess shows effective treatment. PLNP@PANI‐GCS has great potential in treating multidrug‐resistant bacterial infection with low possibility of developing microbial drug resistance and little harm to normal cells.     

A Dual‐Functional Persistently Luminescent Nanocomposite Enables Engineering of Mesenchymal Stem Cells for Homing and Gene Therapy of Glioblastoma

Therapeutically engineered mesenchymal stem cells (MSC) have shown promising capability for glioblastoma (GBM) therapy; however, simultaneous tracking of their migration and long‐term fate is urgently needed for clinical application. This study shows the design and fabrication of a dual‐functional persistent luminescence nanocomposite (LPLNP‐PPT/TRAIL) for effective therapeutic engineering and tracking of MSC in the meantime. LPLNP‐PPT/TRAIL shows low‐toxicity, near‐infrared persistent luminescence emitting without in situ excitation, and superior in vivo deep brain tissue imaging, which can efficiently track the tumortropic migration of the therapeutic engineered MSC. Both in vitro and in vivo findings demonstrate the feasibility of LPLNP‐PPT/TRAIL engineered MSC for inducing apoptosis of glioblastoma cells. This work first establishes an LPLNP‐based dual‐functional platform for cell engineering and provides us implications for GBM‐related diagnosis and therapy.     

Photoconductivity in Mesostructured Thin Films

Mesostructured silica films are widely studied due to their different structures, properties and variety of possible applications. Sodium dodecyl sulfate (SDS)-templated sol-gel silica films possess highly ordered lamellar phase structure. It is expected that molecules and polymer chains line up with these layered structures when incorporated into the films. Mesostructured thin films were doped with Dispersed Red 1 (DR1) and carbazole ((C₆H₄)₂NH)). The films were poled by corona discharge at 120 C. Absorption spectra were recorded as function of the polarization time. Dependence of the absorption coefficient with polarization time was fitted with a Langevin-Debye equation. It shows a saturation level after 60 minutes of polarization. We compare the efficiency of mesostructured thin films with that of amorphous films. The photoconductivity technique was used to determine the charge transport mechanism of these films. From current density versus electrostatic applied field, the parameters for the photovoltaic effect and photoconductivity were determined. Results of the mesostructured thin films are also compared to those of KNbO₃ crystals.