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1.
Dalton Trans ; 53(35): 14648-14655, 2024 Sep 10.
Article de Anglais | MEDLINE | ID: mdl-39189431

RÉSUMÉ

The efficiency of silicon solar cells is still lower than theoretical values, partly due to their inability to utilize the ultraviolet and infrared portions of the solar spectrum. Herein, a novel method using a KCa2Mg2(VO4)3 phosphor with a down-shift effect to improve the photovoltaic performance of silicon solar cells and enhance the utilization of UV light in standard p-type silicon solar cells is proposed. The synthesized phosphors were mixed with an ethylene vinyl acetate (EVA) copolymer and pressed into a film, which was subsequently encapsulated in monocrystalline silicon solar cells. The results show that the addition of this film notably enhanced the photovoltaic performance of the silicon solar cells; the current density was increased by 2.89% (from 33.20 to 34.16 mA cm-2), and the photovoltaic conversion efficiency was improved by 5.69% (from 15.11% to 15.97%) at the optimal concentration compared to bare cells.

2.
Inorg Chem ; 62(51): 21277-21289, 2023 Dec 25.
Article de Anglais | MEDLINE | ID: mdl-38054289

RÉSUMÉ

The detection of antibiotic residues is of great significance in monitoring their overuse in healthcare, livestock and poultry farming, and agricultural production. Herein, EuCl3 and 4,4'-dicarboxyl-diphenoxyethene (H2DPOE) ionothermally reacted in 1-methyl-3-butylimidazolium chloride to give a europium metal-organic framework (Eu-DPOE). Eu-DPOE shows different fluorescence quenching rates for sensing eight antibiotics under different excitation wavelengths. Eu-DPOE displays a fast response, high selectivity, and sensitivity in antibiotic detection by fluorescence quenching. Eu-DPOE can sensitively detect TCs (tetracyclines), NOR (norfloxacin), NFT (furazolidone), ODZ (ornidazole), SDZ (sulfadiazine), and CHL (chloramphenicol) with limits of detection below 0.5 µmol/L. It provides a convenient and rapid tool for sensing antibiotics in aqueous solution. The detection mechanism is a competition absorption between DPOE2- and antibiotics with the supports from powder X-ray diffraction (PXRD), UV-vis spectra, and fluorescence lifetime. With a composite membrane of poly(vinylidene fluoride) (PVDF) matrix loading Eu-DPOE (Eu-DPOE@PVDF), Eu-DPOE@PVDF exhibits a visual fluorescence response to NOR under a 254 nm UV lamp and NFT and CTC under 365 nm. Eu-DPOE@PVDF is applied in the quantitative detection of CTC, NOR, and NFT in lake water with recovery rates ranging from 88.37 to 113.8%. Totally, fluorescence-quenched Eu-DPOE@PVDF exhibits a fast response, high selectivity, and sensitivity in sensing CTC, NOR, and NFT.


Sujet(s)
Antibactériens , Réseaux organométalliques , Réseaux organométalliques/composition chimique , Europium/composition chimique , Polymères , Lacs , Eau
3.
Inorg Chem ; 62(49): 20364-20371, 2023 Dec 11.
Article de Anglais | MEDLINE | ID: mdl-37991326

RÉSUMÉ

A novel zeolite-like topology oxonitridosilicate La3.6Ba1.7Si5N10O2.1 with the space group Amm2 (no. 38) and lattice parameters a = 9.5193 (3) Å, b = 16.7011 (5) Å, c = 26.0279 (8) Å, and Z = 12 has been synthesized by a high-temperature solid-state reaction. The crystal structure of La3.6Ba1.7Si5N10O2.1 has four different kinds of tiling, and the cages in the structure are filled with La, Ba, and O atoms. The presence of a noncentrosymmetric space group further suggests its potential for nonlinear optical (NLO) applications, and La3.6Ba1.7Si5N10O2.1 demonstrated a stronger second-harmonic generation (SHG) response than that of SiO2.

4.
Chem Commun (Camb) ; 59(71): 10612-10615, 2023 Aug 31.
Article de Anglais | MEDLINE | ID: mdl-37555283

RÉSUMÉ

The exploration of transition metal oxynitrides has garnered significant interest due to their intriguing property diversity. Herein, we present a promising new transition metal oxynitride BaLa5V2O3N7, which features an anti-perovskite structure type. This unique structural configuration endows the material with remarkable conductivity, particularly at low temperatures, paving the way for the material to be used in a wide range of technological applications.

5.
ACS Appl Mater Interfaces ; 15(17): 21040-21048, 2023 May 03.
Article de Anglais | MEDLINE | ID: mdl-37074218

RÉSUMÉ

Lithium-sulfur (Li-S) batteries demonstrate great potential for next-generation electrochemical energy storage systems because of their high specific energy and low-cost materials. However, the shuttling behavior and slow kinetics of intermediate polysulfide (PS) conversion pose a major obstacle to the practical application of Li-S batteries. Herein, CrP within a porous nanopolyhedron architecture derived from a metal-organic framework (CrP@MOF) is developed as a highly efficient nanocatalyst and S host to address these issues. Theoretical and experimental analyses demonstrate that CrP@MOF has a remarkable binding strength to trap soluble PS species. In addition, CrP@MOF shows abundant active sites to catalyze the PS conversion, accelerate Li-ion diffusion, and induce the precipitation/decomposition of Li2S. As a result, the CrP@MOF-containing Li-S batteries demonstrate over 67% capacity retention over 1000 cycles at 1 C, ∼100% Coulombic efficiency, and high rate capability (674.6 mAh g-1 at 4 C). In brief, CrP nanocatalysts accelerate the PS conversion and improve the overall performance of Li-S batteries.

6.
Adv Sci (Weinh) ; 10(9): e2206055, 2023 Mar.
Article de Anglais | MEDLINE | ID: mdl-36658694

RÉSUMÉ

The utilization of lignin, the most abundant aromatic biomass component, is at the forefront of sustainable engineering, energy, and environment research, where its abundance and low-cost features enable widespread application. Constructing lignin into material parts with controlled and desired macro- and microstructures and properties via additive manufacturing has been recognized as a promising technology and paves the way to the practical application of lignin. Considering the rapid development and significant progress recently achieved in this field, a comprehensive and critical review and outlook on three-dimensional (3D) printing of lignin is highly desirable. This article fulfils this demand with an overview on the structure of lignin and presents the state-of-the-art of 3D printing of pristine lignin and lignin-based composites, and highlights the key challenges. It is attempted to deliver better fundamental understanding of the impacts of morphology, microstructure, physical, chemical, and biological modifications, and composition/hybrids on the rheological behavior of lignin/polymer blends, as well as, on the mechanical, physical, and chemical performance of the 3D printed lignin-based materials. The main points toward future developments involve hybrid manufacturing, in situ polymerization, and surface tension or energy driven molecular segregation are also elaborated and discussed to promote the high-value utilization of lignin.

7.
China Tropical Medicine ; (12): 612-2023.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-979775

RÉSUMÉ

@#Abstract: Objective To analyze the epidemiological characteristics of pulmonary tuberculosis (PTB) in Ankang City from 2011 to 2021, so as to provide a scientific basis for the formulation of PTB prevention and control strategy. Methods Descriptive statistics were used to analyze the epidemiological characteristics of PTB in Ankang City from 2011 to 2021, and a time series model was established to quantitatively predict the incidence of pulmonary tuberculosis in 2023. Results The incidence rate in Ankang City showed a significant upward trend from 2011 to 2017, and a more obvious downward trend in 2017-2021 (P<0.05), and the decrease rate in 2021 was 40.36% compared with that in 2017. The proportion of etiological positivity increased from 12.5% in 2014 to over 50.00% after 2019. The incidence season was mainly concentrated in the first quarter, accounting for 28.39% of the annual incidence. High incidence areas were concentrated in the south of Ankang: Langao County, Ziyang County and Zhenping County, with 128.32/100 000, 117.07/100 000 and 110.44/100 000, respectively. Low incidence areas were located in the north of Ankang: Ningshan County, with 60.62/100 000. Farmers and students were the high incidence groups, accounting for 81.80% and 4.97% of the total cases respectively. The incidence of young children was relatively low, but cases were reported every year. The incidence rate of male was 2.39 times that of female. The age of onset increased significantly from 15 years old, and the peak incidence was in the age group of 60-<80 years old, followed by the age group of 45-<60 years old, the average annual incidence was 136.44/100 000 and 104.47/100 000, respectively. The model ARIMA(0,1,1)(0,1,1)12 predicted that the incidence of the disease generally increased from October 2022 to March 2023, then steadily decreased, and increased again in December. Conclusions The incidence of tuberculosis varies in different areas of Ankang City, and males, farmers, students and the elderly are all factors of high incidence of tuberculosis. Therefore, different prevention and control strategies should be adopted according to the characteristics of population in different areas. The number of cases in Ankang City in 2023 showed an overall downward trend, which can provide a reference for the prevention and control of PTB.

8.
RSC Adv ; 12(44): 28414-28421, 2022 Oct 04.
Article de Anglais | MEDLINE | ID: mdl-36320542

RÉSUMÉ

Oxygen-depleted samples [Y2Ti2O7-x ]2x+(2xe-) (0 ≤ x ≤ 1.0) were prepared by reducing Y2TiO7 powders at 500 °C to 650 °C using CaH2 as a reductive agent, where x represents the content of , which was determined by thermogravimetric analysis. Powder X-ray diffraction patterns illustrate that the pure pyrochlore phase is kept for the samples with x ≤ 1.0, whereas the apparent x values surpass 1.0, and the impurity phase Y2O3 appears. The electride [Y2Ti2O7-x ]2x+(2xe-) (x ≈ 1.0) can be obtained under a reductive condition, in which the concentration of VO is 7.75 × 1021 cm-3. The electron paramagnetic resonance measurements gave the concentration of unpaired electrons in the electride as 1.30 × 1021 cm-3, indicating that the degree of the ionization of is less than 10%. Conductivity measurements for a sintered pellet sample (relative density ∼ 70%) indicate that the electride has quite high conductivity (∼1.09 S cm-1 at 300 K). The conduction was interpreted by using the variable range hopping mechanisms.

9.
Inorg Chem ; 61(36): 14322-14332, 2022 Sep 12.
Article de Anglais | MEDLINE | ID: mdl-36026489

RÉSUMÉ

This work presents three series of Eu/Tb metal-organic frameworks (MOFs) containing benzophenone-4,4'-dicarboxylic acid (H2BPNDC), 4,4'-dicarboxydiphenyl ether (H2OBA), and terephthalic acid (H2BDC) as the ligands. Eu/Tb MOFs have the same structural features in that their 3D frameworks are simplified as 2,3,10-connected {42.6}2{46.618.819.102}{4}2 topological networks. The solid-state fluorescence spectra of three Eu/Tb MOF series are attributed to the combined emissions of 5D0 → 7FJ (J = 1-4) transitions in Eu3+ and 5D4 → 7FJ (J = 6-5) transitions in Tb3+. The nEu:nTb of Eu/Tb MOFs is optimized as 1:69 based on the relationships between ITb(545)/IEu(614) and nEu:nTb; that is, Eu0.0143Tb0.9857-L (L = BPNDC2-, OBA2-, and BDC2-) were selected to carry out the following temperature (T)-sensing tests. The fluorescence mechanism of Eu0.0143Tb0.9857-L can be explained by a ligand-to-metal charge transfer combined with an intermetallic Tb3+ → Eu3+ energy transfer. The T-dependent fluorescence indicates linear relationships with sensitivities of 1.85% K-1 for Eu0.0143Tb0.9857-BPNDC, 6.49% K-1 for Eu0.0143Tb0.9857-OBA, and 0.28% K-1 for Eu0.0143Tb0.9857-BDC. The influence of T on the lowest excited triplet energy levels (T1 values) of the ligands reveals that the ligand energy regulation impacts their fluorescence properties, including the sensitivity, fluorescence quenching rate, quantum yield, and fluorescence lifetime. This shows that Eu0.0143Tb0.9857-BPNDC is sufficiently sensitive to T, making it applicable in noncontact T measurements.

10.
Chem Commun (Camb) ; 58(30): 4739-4742, 2022 Apr 12.
Article de Anglais | MEDLINE | ID: mdl-35322832

RÉSUMÉ

Flux synthesis is an effective method to discover large crystals of new compounds. In this paper, a solid-state reaction in Li flux produced a new nitridolithosilicate La4Ba3Li3Si9N19 in the orthorhombic space group Cmcm (No. 63) with lattice parameters of a = 9.7263(1), b = 18.2746(2), c = 11.2929(1) Å, and Z = 4. The La4Ba3Li3Si9N19 exhibits a 3-D framework based on triangular clusters (3-rings) formed by vertex-sharing SiN4 tetrahedra. The rare earth Pr3+-doped La4Ba3Li3Si9N19 emits a narrow-band red emission peaking at approximately 640 nm with a full width at half-maximum of 50 nm when excited under ultraviolet light.

11.
Zhongguo Zhong Yao Za Zhi ; 47(6): 1433-1437, 2022 Mar.
Article de Chinois | MEDLINE | ID: mdl-35347940

RÉSUMÉ

Panacis Quinquefolii Radix is the dry root of Panax quinquefolium, which is a perennial plant of Araliaceae. The plant has a long growth cycle and serious growth barrier problem, which leads to the use of pesticides. As a result, the pesticide residues in Panacis Quinquefolii Radix are arousing great concern. This paper reviews the research findings on the investigation, detection methods, content analysis and risk assessment of pesticide residues in Panacis Quinquefolii Radix since 1993, and compares the pesticide residue limit standards of different countries and regions. The pesticide residues in Panacis Quinquefolii Radix have been changing from organochlorines with high toxicity to triazines and triazoles with low toxicity. The pesticide residues are generally low, while the pollution of pentachloronitrobenzene and other pesticides still exist. The detection method has evolved from chromatography to chromatography-mass spectrometry. There are no reports of health risks caused by pesticide residues of Panacis Quinquefolii Radix. Pesticide residue is a major factor restricting the sound development of Panacis Quinquefolii Radix industry in China. Therefore, we suggest to improve the registration of pesticides applied to the plant, popularize mature ecological planting mode and supporting technology, and strengthen the research on the risk assessment and limit standard of pesticide residue in Panacis Quinquefolii Radix.


Sujet(s)
Médicaments issus de plantes chinoises , Ginsénosides , Panax , Résidus de pesticides , Médicaments issus de plantes chinoises/composition chimique , Ginsénosides/analyse , Spectrométrie de masse , Panax/composition chimique , Résidus de pesticides/analyse
12.
Dalton Trans ; 51(2): 553-561, 2022 Jan 04.
Article de Anglais | MEDLINE | ID: mdl-34901985

RÉSUMÉ

Traditional fluorescent materials used in the anti-counterfeiting field usually exhibit monochromatic luminescence at a single-wavelength excitation, which is easily forged by sophisticated counterfeiters. In this work, Zn2GeO4:Mn,x%Li (x = 0 and 20), Zn2GeO4-NaLiGe4O9:Mn,x%Li (x = 50 and 70) and NaLiGe4O9:Mn micro-phosphors with multi-chromatic and multi-mode luminescence have been successfully synthesized via a hydrothermal approach followed by an annealing treatment. As expected these Li+ doped Zn2GeO4:Mn and Zn2GeO4-NaLiGe4O9:Mn phosphors exhibit a double peak emission including a long green afterglow (∼540 nm) and red photoluminescence (∼668 nm). By tuning Li+ doping concentrations, a gradual colour output and a tuneable afterglow duration are achieved. In particular, the Zn2GeO4:Mn,Li and NaLiGe4O9:Mn phosphors exhibit excellent performance as security inks for printing luminescent numbers and anti-counterfeiting patterns, which show an afterglow time-dependent or excitation wavelength-dependent luminescence colour evolution. This work proves the feasibility of the Li+ doping strategy in emission tuning, which can stimulate further studies on multi-mode luminescent materials for anti-counterfeiting applications.

13.
Obes Surg ; 31(9): 4005-4014, 2021 09.
Article de Anglais | MEDLINE | ID: mdl-34240316

RÉSUMÉ

PURPOSE: This study aims to examine the changes of glucose metabolism, glucose variability (GV), and ghrelin secretion within 1 week following SG in Chinese patients with obesity. MATERIALS AND METHODS: Forty-nine patients with obesity (15 with type 2 diabetes) were enrolled to undergo SG. Within 1 week before and after surgery, liquid meal tests were performed in all subjects, and continuous glucose monitoring (CGM) was performed in diabetic patients. Blood samples were collected at 0, 15, 30, 45, 60, 120, and 180 min for glucose, C-peptide, insulin, and ghrelin analysis in liquid meal test. Mean amplitude of glucose excursions (MAGE), standard deviations (SD), and percent time-in-range (%TIR) determined by CGM were analyzed. RESULTS: Both in diabetic and non-diabetic groups, significant decrease was observed in glucose, insulin, C-peptide, and ghrelin. Homeostasis model assessment-insulin resistance and liver fat content was decreased. In diabetic group, MAGE and SD were decreased significantly, and the percent time-in-range was higher. The decrease in blood glucose was positively correlated with the decrease in ghrelin concentration in non-diabetic group. CONCLUSION: Within 1 week after SG, both glucose metabolism and glucose variability were improved significantly. Suppression of ghrelin secretion postoperatively might be a driver of this early improved glycemia homeostasis.


Sujet(s)
Diabète de type 2 , Obésité morbide , Glycémie , Autosurveillance glycémique , Diabète de type 2/chirurgie , Gastrectomie , Ghréline , Glucose , Humains , Insuline , Obésité morbide/chirurgie
14.
Chem Commun (Camb) ; 57(31): 3761-3764, 2021 Apr 21.
Article de Anglais | MEDLINE | ID: mdl-33729261

RÉSUMÉ

The new oxonitridosilicates Ln4-xSr2+xSi5N12-xOx (Ln = La, Ce) were synthesized by high temperature solid-state reactions. The crystal structures were solved and refined from both single-crystal and powder X-ray diffraction data. These oxonitridosilicate compounds crystallize in the monoclinic space group P21/n (no. 14) and exhibit a double-layer structure made up of corner-sharing Si(O/N)4 tetrahedra. When excited with near-UV and blue light, the Pr3+ doped La2.31Sr3.69Si5N10.31O1.69 phosphor shows a narrow-band red emission peaking at 625 nm with a full width at half-maximum of 40 nm.

15.
ISME J ; 15(8): 2474-2489, 2021 08.
Article de Anglais | MEDLINE | ID: mdl-33712698

RÉSUMÉ

While soil erosion drives land degradation, the impact of erosion on soil microbial communities and multiple soil functions remains unclear. This hinders our ability to assess the true impact of erosion on soil ecosystem services and our ability to restore eroded environments. Here we examined the effect of erosion on microbial communities at two sites with contrasting soil texture and climates. Eroded plots had lower microbial network complexity, fewer microbial taxa, and fewer associations among microbial taxa, relative to non-eroded plots. Soil erosion also shifted microbial community composition, with decreased relative abundances of dominant phyla such as Proteobacteria, Bacteroidetes, and Gemmatimonadetes. In contrast, erosion led to an increase in the relative abundances of some bacterial families involved in N cycling, such as Acetobacteraceae and Beijerinckiaceae. Changes in microbiota characteristics were strongly related with erosion-induced changes in soil multifunctionality. Together, these results demonstrate that soil erosion has a significant negative impact on soil microbial diversity and functionality.


Sujet(s)
Microbiote , Sol , Bactéries/génétique , Humains , Consortiums microbiens , Microbiologie du sol
16.
Chinese Journal of School Health ; (12): 922-924, 2021.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-881437

RÉSUMÉ

Objective@#To investigate risk factors and epidemiological characteristics of bacillary dysentery outbreaks in three schools, and to provide scientific basis for the prevention and control of the epidemic in the future.@*Methods@#Case definition was established. All suspected, possible and confirmed cases of all students and faculty members from 3 schools (A, B, C) were selected for epidemiological investigation. Control group was used for case-control analysis, and relevant samples were collected for laboratory testing.@*Results@#A total of 132 cases were found in 3 schools, all of which were from students, with the incidence rate of 17.74%. The morbidity in kindergarten A was 20.00%, in center primary school B it was 21.74%, and in junior middle school C it was 11.61%. Cohort studies and casecontrol studies suggested that schools are exposed places and that washing hands with raw water in schools was possible risk factor [OR(95%CI) =4.50(1.01-20.11)]. Nine stool samples were tested in laboratory, among which 8 were positive for Shigella(88.99%), and Shigella was detected in the end nodes of school s pipeline network, the water samples from canteen bucket, and the floor drains of sewer pipe.@*Conclusion@#The bacillary dysentery outbreaks in 3 schools was caused by Shigella, which may be due to fecal contamination of domestic water in 3 schools before the start of the school year. It is suggested to strengthen the management of centralized water supply and construction in rural areas, intensify the supervision at all levels, and sanitation and disinfection before school opens at all levels.

17.
Dalton Trans ; 50(1): 143-150, 2021 Jan 07.
Article de Anglais | MEDLINE | ID: mdl-33284932

RÉSUMÉ

The detection of pH and water is of significance in natural and production processes. The ionothermal reactions of 4,4'-oxybisbenzoic acid (H2OBA) with Eu3+ and Tb3+ produced [M(OBA)(H2O)Cl] (M = Eu3+ (1) and Tb3+ (2)) and heteronuclear [Eu0.05Tb0.95(OBA)(H2O)Cl] (3). 3 emits the combined characteristic transitions of Eu3+ and Tb3+. Its energy transition processes can be disturbed by pH and water. The emission colors of 3 follow pH changes. It emits blue light when pH = 1-2, in which OBA2- turns into H2OBA based on the acid-base equilibrium. When pH = 3-11, the emission colors change from green to orange and ITb/IEu exhibits a linearity of ITb/IEu = 6.7482-0.5971·pH; the emissions are quenched at pH = 12-13, due to OH- destroying the delocalized conjugated system of 3. 3 shows a fluorescence response to water with a linearity of ITb/IEu = 0.30353 + 0.15042·VH2O% within 0-0.8% VH2O%. The green (G) and red (R) color intensities of the paper-based MOF sensor of 3 reveal a trinomial fitting equation of G/R = 4.16334 - 1.23014·pH + 0.14036·pH2- 0.00551·pH3 when pH = 3-11. 3 can be used as a ratiometric fluorescent sensor to detect pH and water and the paper-based MOF sensor can also be used in on-site pH detection.


Sujet(s)
Benzoates/composition chimique , Europium/composition chimique , Concentration en ions d'hydrogène , Réseaux organométalliques/composition chimique , Terbium/composition chimique , Eau/analyse , Colorimétrie , Fluorescence , Fluorimétrie
18.
Chem Asian J ; 15(10): 1590-1597, 2020 May 15.
Article de Anglais | MEDLINE | ID: mdl-32227621

RÉSUMÉ

Fabricating highly efficient electrocatalysts for electrochemical hydrogen generation is a top priority to relief the global energy crisis and environmental contamination. Herein, a rational synthetic strategy is developed for constructing well-defined FeP-CoMoP hierarchical nanostructures (HNSs). In general terms, the self-supported Co nanorods (NRs) are grown on conductive carbon cloth and directly serve as a self-sacrificing template. After solvothermal treatment, Co NRs are converted into well-ordered Co-Mo nanotubes (NTs). Subsequently, the small-sized Fe oxyhydroxide nanorods arrays are hydrothermally grown on the surface of Co-Mo NTs to form Fe-Co-Mo HNSs, which are then converted into FeP-CoMoP HNSs through a facile phosphorization treatment. FeP-CoMoP HNSs display high activity for hydrogen evolution reaction (HER) with an ultralow cathodic overpotential of 33 mV at 10 mA cm-2 and a Tafel slope of 51 mV dec-1 . Moreover, FeP-CoMoP HNSs also possess an excellent electrochemical durability in alkaline media. First-principles density functional theory (DFT) calculations demonstrate that the remarkable HER activitiy of FeP-CoMoP HNSs originates from the synergistic effect between FeP and CoMoP.

19.
Inorg Chem ; 58(7): 4412-4419, 2019 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-30888160

RÉSUMÉ

A novel red oxyfluoride phosphor K3TaO2F4:Mn4+ has been prepared by a simple two-step synthesis method. The structure, composition, and luminescence properties of K3TaO2F4:Mn4+ phosphors were investigated and discussed in detail. The real structure of K3TaO2F4 was carefully studied through X-ray powder diffraction data Rietveld refinement. K3TaO2F4 holds a D4 h group symmetry [TaO2F4]3- octahedron with the oxygen occupying the para-position. Under ultraviolet (UV) and blue light excitation, K3TaO2F4:Mn4+ phosphor emits a narrow band red emission peaking at 630 nm. High-performance warm white-light-emitting diodes (WLEDs) were fabricated using a blue LED chip, YAG:Ce3+ yellow phosphor, and K3TaO2F4:Mn4+ red phosphor. This device exhibits high color quality (CCT = 3488 K, Ra = 93.0, R9 = 90.0), which indicates that Mn4+-doped K3TaO2F4 would be a promising red phosphor for WLED applications.

20.
Occup Environ Med ; 76(3): 151-156, 2019 03.
Article de Anglais | MEDLINE | ID: mdl-30661027

RÉSUMÉ

OBJECTIVES: A significant number of researches have evidenced that occupational lead (Pb) exposure increased risks of cardiovascular disease. However, evidences about the potential effects of Pb on the cardiac conduction system are sparse and inconclusive. Besides, ryanodine receptors (RyRs) induced dysfunction of cardiac excitation contraction coupling which is considered to be one of the mechanisms in cardiovascular diseases. Therefore, we examined the association between occupational Pb exposure and ECG conduction abnormalities, as well as RyRs in Pb-induced ECG abnormalities. METHODS: We investigated 529 Pb smelter workers, and measured blood lead (BPb), zinc protoporphyrin (ZPP), ECG outcomes and RyR expression levels. Based on BPb levels, the workers were divided into three groups: the BPb not elevated group, the BPb elevated group and the Pb poisoning group. Descriptive and multivariable analyses were performed. RESULTS: Compared with the BPb not elevated group, the Pb poisoning group had a higher incidence of high QRS voltage, and a lower level of RyR1 gene expression (p<0.05). Further unconditional multivariable logistic regression analyses showed that high QRS voltage was positively related to BPb (OR=1.045, 95% CI 1.014 to 1.078) and inversely associated with RyR1 expression (OR=0.042, 95% CI 0.002 to 0.980) after adjusting for potential confounders. In addition, multiple linear regression analyses showed that the QTc interval was positively associated with ZPP (ß=0.299, 95% CI 0.130 to 0.468) after adjusting for potential confounders. CONCLUSIONS: Our study provided evidences that occupational exposure to Pb may be associated with worse ECG outcomes (high QRS voltage), which might be related to decreased levels of RyR1.


Sujet(s)
Intoxication par le plomb/génétique , Intoxication par le plomb/physiopathologie , Plomb/sang , Exposition professionnelle , Canal de libération du calcium du récepteur à la ryanodine/génétique , Adulte , Études transversales , Électrocardiographie , Système de conduction du coeur/physiopathologie , Humains , Intoxication par le plomb/sang , Modèles linéaires , Modèles logistiques , Syndrome du QT long/induit chimiquement , Syndrome du QT long/diagnostic , Mâle , Analyse multifactorielle , Protoporphyrines/sang , Jeune adulte
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