Temperature dependent luminescence of Dy3þ doped BaYF5 nanoparticles for optical thermometry

Zhongmin Cao,Shaoshuai Zhou,Guicheng Jiang,Yonghu Chen,Changkui Duan,Min Yin 한국물리학회 2014 Current Applied Physics Vol.14 No.8

Dy3þ doped BaYF5 nanoparticles with tetragonal structure were synthesized by hydrothermal method and solvothermal method. The structural and the luminescent properties of the samples were characterized by X-ray diffraction pattern, TEM and photoluminescence spectra. Emission of Dy3þ originated from 4I15/2 located at 450 nm and 4F9/2 located at 478 nm, 573 nm and 660 nm were observed under excitation of 355 nm laser. Behavior of fluorescence intensity ratio with temperature increasing from room temperature to approximately 800 K was investigated. And the optimum temperature range for thermometry is obtained to be 550e800 K according to its sensitivity-temperature relation, indicating the potential application of BaYF5:Dy3þ as a luminescent temperature sensor.

One-Step Hydrothermal Synthesis of Bi2S3-TiO2-RGO Composites with Enhanced Visible Light Photocatalytic Activities

Yanan Li,Zhongmin Liu,Yaru Li,Yongchuan Wu,Jitao Chen,Yanjun Liu,Ping Na 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.5

The Bi2S3-TiO2-RGO composites were synthesized by a facile one-step hydrothermal method and applied for the photocatalytic degradation of Rhodamine B (Rh B) under the visible light. The Bi2S3-TiO2-RGO composites were characterized by transmission electron microscopy, X-ray diffraction, Raman and Fourier transform infrared spectrometer. The results indicated that the Bi2S3-TiO2-RGO composites were successfully prepared, and Ti-O-C and S-C bonds were existing among Bi2S3, TiO2 as well as RGO. Furthermore, the photocatalytic ability of Bi2S3-TiO2-RGO composites was excellent under visible light due to its responding to the whole visible light region, low recombination rate of photogenerated electron–hole pairs and relatively negative conduction band. Rh B photocatalytic degradation rate was 99.5% after 50 min and still could reach 98.4% after five cycles. Finally, a formation mechanism as well as a photocatalytic mechanism of Bi2S3-TiO2-RGO composites were proposed based on the experimental results.

The hydrogen storage nanomaterial MgH2 improves irradiation-induced male fertility impairment by suppressing oxidative stress

Jing Ma,Suhe Dong,Hongtao Lu,Zhongmin Chen,Huijie Yu,Xuejun Sun,Renjun Peng,Wei Li,Sinian Wang,Qisheng Jiang,Fengsheng Li,Li Ma 한국생체재료학회 2022 생체재료학회지 Vol.26 No.2

Objective: This study aimed to reveal the protective effect of hydrogen storage nanomaterial MgH2 on radiationinduced male fertility impairment. Methods: The characterization of MgH2 were analyzed by scanning electron microscopy (SEM) and particle size analyzer. The safety of MgH2 were evaluated in vivo and in vitro. The radioprotective effect of MgH2 on the reproductive system were analyzed in mice, including sperm quality, genetic effect, spermatogenesis, and hormone secretion. ESR, flow cytometry and western blotting assay were used to reveal the underlying mechanisms. Results: MgH2 had an irregular spherical morphology and a particle size of approximately 463.2 nm, and the content of Mg reached 71.46%. MgH2 was safe and nontoxic in mice and cells. After irradiation, MgH2 treatment significantly protected testicular structure, increased sperm density, improved sperm motility, reduced deformity rates, and reduced the genetic toxicity. Particularly, the sperm motility were consistent with those in MH mice and human semen samples. Furthermore, MgH2 treatment could maintain hormone secretion and testicular spermatogenesis, especially the generation of Sertoli cells, spermatogonia and round sperm cells. In vitro, MgH2 eliminated the [·OH], suppressed the irradiation-induced increase in ROS production, and effectively alleviated the increase in MDA contents. Moreover, MgH2 significantly ameliorated apoptosis in testes and cells and reversed the G2/M phase cell cycle arrest induced by irradiation. In addition, MgH2 inhibited the activation of radiation-induced inflammation and pyroptosis. Conclusion: MgH2 improved irradiation-induced male fertility impairment by eliminating hydroxyl free radicals.

K-doping effect of the superconductivity in K2xFeTe1-xSx (0.07 ≤ x ≤ 0.3)

Cheng Cheng,Zhenjie Feng,Qing Li,Tao Li,Qiang Hou,Fei Chen,Zhongmin Ou,Jun-Yi Ge,Shixun Cao,Jincang Zhang 한국물리학회 2019 Current Applied Physics Vol.19 No.4

Bulk samples of K doping K2xFeTe1-xSx with x=0.07, 0.1, 0.2, 0.3 are successfully prepared by using easy-to-use stable compound K2S as the reactant. The lattice constant calculated from X-ray diffraction patterns indicate that K ions enter the Fe-Te-S layers. K doping is beneficial enhance the superconductivity transition temperature from the R-T curves. The apparent diamagnetic signal is observed in M-T curves when the content of K is smaller than 0.1. However, differential curves (dM/dT) in K-rich samples appear sharp slope mutations, which means that the Meissner effect signal is covered by the increased excess ferromagnetic ions. The number of excess Fe magnetic ions is proportional to K content, which may play an important role in determining the superconductivity.

Effective transportation of electrons/Li ions in V2O3 nanoparticle/carboncoated stainless steel composite electrodes for lithium-ion storage

Yaxiong Tian,Jianghua Zhang,Tunmise Ayode Otitoju,Honggang Wang,Huaxia Chen,Lin Zhu,Zhongmin Feng,Ting Sun 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.114 No.-

The performance of V2O3 is threatened as a result of relatively sluggish electrons/ion transportation andstructural pulverization in lithium-ion batteries. The rational design of the electrode structure to exhibitgreat lithium storage of V2O3 is crucial. In this work, we report stable composite electrodes by integratingV2O3 nanoparticles with an uneven carbon-coated stainless-steel oxide (V2O3/C/SS) current collector viaan in-situ growth method. They allow fast electrical conductivity through the carbon coating and reductionstrategy. Meanwhile, the small nanoparticle size of V2O3 on V2O3/C/SS as well as the undestroyed 3DV–V skeleton are helpful to Li-ion diffusion. The weak interaction between Li ions and V2O3 achieves fastand high Li storage behavior, which proves by electrochemical kinetics analysis and DFT calculation. Theelectrode delivers high rate capacitive and long cycling stability with 564 mAh g1 and 310 mAh g1 at100 mA g1 and 1 A g1, respectively, and a specific capacity of 118 mAh g1 is achieved after 1000 cyclesat 5 A g1. The excellent electrochemical performance may be ascribed to the unique design for effectiveelectron and Li-ion transportation. This work offers a new prospect for the development of highperformancebinder-free V2O3-based electrodes.

New Insights Into Refractory Chronic Cough and Unexplained Chronic Cough: A 6-Year Ambispective Cohort Study

Zhang Mengru,Morice Alyn H.,Si Fengli,Zhang Li,Chen Qiang,Wang Shengyuan,Zhu Yiqing,Xu Xianghuai,Yu Li,Qiu Zhongmin 대한천식알레르기학회 2023 Allergy, Asthma & Immunology Research Vol.15 No.6

Purpose: Only limited studies have depicted the unique features and management of refractory chronic cough (RCC) and unexplained chronic cough (UCC). These led to the initiation of this study, which reported the demographic characteristics, manifestations, and long-term outcomes on a large series of consecutive RCC/UCC patients, providing a guideline-led real-world clinical experience. Methods: Retrospective baseline information was obtained from Clinical Research Database (January 2016 to May 2021). At least 6 months after the last clinic visit, included subjects were prospectively followed up. Results: Three hundred and sixty-nine RCC and UCC patients (199 females, 53.9%) were analyzed. The median cough duration was 24.0 (12.0–72.0) months. Laryngeal symptoms were reported in 95.9% of the patients. The common triggers for coughing were talking (74.9%), pungent odors (47.3%), eating (45.5%), and cold air (42.8%). RCC was considered in 38.2%, and the remainder of 228 patients had UCC, with an equal sex distribution (P = 0.66). Among the 141 RCCs, 90.8% (128) had refractory reflux cough, which was more responsive to current treatments (P < 0.01). Although most features and test results between RCC and UCC were similar, UCC was more commonly inappropriately treated (P < 0.01). Nineteen (7.7–41.1) months after the final clinic visit, 31.2% still coughed persistently, while 68.8% reported cough improvement or remission. RCC reported more favorable treatment outcomes (including cough improvement, control, and spontaneous remission) than UCC (P < 0.01). Coughs with long duration before the initial cough clinic visit (P < 0.01), frequent urinary incontinence (P < 0.01), and being sensitive to “talking” (P < 0.01) or “cold air” (P < 0.01) were less likely to be solved. Conclusions: The current treatments only improve cough symptoms in two-thirds of patients. Clinical indicators for treatment failure were those coughing for long duration and being sensitive to “talking” or “cold air.”