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1.
J Glob Health ; 13: 04174, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38037705

RESUMO

Background: The burden of inflammatory bowel disease (IBD) among children and adolescents is rising globally, with substantial variation in levels and trends of disease in different countries and regions, while data on the burden and trends were sparse in children and adolescents. We aimed to assess the trends and geographical differences in children and adolescents aged zero to 19 in 204 countries and territories over the past 30 years. Methods: Data on IBD among children and adolescents was collected from the Global Burden of Disease (GBD) 2019 database from 1990 to 2019. We used the GBD data and methodologies to describe the change in the burden of IBD among children and adolescents involving prevalence, incidence, disability-adjusted life years (DALYs), and mortality. Results: Globally, the IBD prevalence cases increased between 1990 and 2019. Annual percentage changes (AAPC) = 0.15; 95% confidence interval (CI) = 0.11-0.19, and incidence cases of IBD increased from 20 897.4 (95% CI = 17 008.6-25 520.2 in 1990 to 25 658.6 (95% CI = 21 268.5-31 075.6) in 2019, representing a 22.78% increase, DALYs cases decreased between 1990 and 2019 (AAPC = -3.02; 95% CI = -3.15 to -2.89), and mortality cases of IBD decreased from 2756.5 (95% CI = 1162.6-4484.9) in 1990 to 1208.0 (95% CI = 802.4-1651.4) in 2019, representing a 56.17% decrease. Decomposition analysis showed that IBD prevalence and incidence increased significantly, and a trend exhibited a decrease in underlying age and population-adjusted IBD DALYs and mortality rates. Correlation analysis showed that countries with high health care quality and access (HAQ) had relatively higher IBD age-standardised prevalence rate (ASPR) and age-standardised incidence rate (ASIR), but lower age-standardised DALYs rate (ASDR) and age-standardised mortality rate (ASMR). Conclusions: Global prevalence and incidence rate of IBD among children and adolescents have been increasing from 1990 to 2019, while the DALYs and mortality have been decreasing. Rising prevalence and rising incidence in areas with historically low rates will have crucial health and economic implications.


Assuntos
Carga Global da Doença , Doenças Inflamatórias Intestinais , Humanos , Criança , Adolescente , Idoso , Anos de Vida Ajustados por Qualidade de Vida , Prevalência , Incidência , China/epidemiologia , Doenças Inflamatórias Intestinais/epidemiologia , Saúde Global
2.
Front Cell Dev Biol ; 9: 650999, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33898446

RESUMO

Bladder cancer has easy recurrence characteristics, but its occurrence and development mechanism are still unclear. Non-coding RNA is a kind of RNA that exists widely and cannot be translated into proteins, which has played a key role in the regulation of biological functions of tumor cells. However, the regulation mechanism of non-coding RNA on bladder tumors is not fully understood. By microarray analysis and database analysis, we found that LINC00511 was significantly highly expressed in bladder cancer. The expressions of LINC00511, miR-143-3p, and PCMT in bladder cancer tissues and cells were detected by quantitative reverse transcription-polymerase chain reaction. The relationship between the expressions of miR-143-3p and PCMT1 and the clinicopathological parameters of the tumor was analyzed. The proliferation and invasion of bladder cancer cells were detected by MTT assay and Transwell assay. The expression levels of E-cadherin and vimentin in bladder cancer cells were detected by Western blot. Cell apoptosis was detected by flow cytometry. In vivo, TCCSUP or SW780 cells were inoculated into BALB/c nude mice to detect tumor volume and weight. Bioinformatics and dual luciferase reporter gene were used to analyze the relationship between LINC00511 and miR-143-3p and its downstream target gene PCMT1. The results showed that LINC00511 could target miR-143-3p/PCMT1 to regulate the proliferation, migration, and apoptosis of bladder cancer TCCSUP or SW780 cells and promote the occurrence and development of bladder cancer.

3.
Alzheimers Res Ther ; 11(1): 106, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847879

RESUMO

BACKGROUND: Brain amyloid deposition is one of the main pathological characteristics of Alzheimer's disease (AD). Soluble oligomers formed during the process that causes ß-amyloid (Aß) to aggregate into plaques are considered to have major neurotoxicity. Currently, drug development for the treatment of Alzheimer's disease has encountered serious difficulties. Our newly proposed solution is to accelerate the aggregation of Aß to reduce the amount of cytotoxic Aß oligomers in brain tissue. This strategy differs from the existing strategy of reducing the total Aß content and the number of amyloid plaques. METHOD: In this study, we screened a small library and found that a flavonoid compound (ZGM1) promoted the aggregation of ß-amyloid (Aß). We further verified the binding of ZGM1 to Aß42 using a microscale thermophoresis (MST) assay. Subsequently, we used dot blotting (DB), transmission electron microscopy (TEM), and thioflavin T fluorescence (ThT) measurements to study the aggregation of Aß under the influence of ZGM1. By using cell experiments, we determined whether ZGM1 can inhibit the cytotoxicity of Aß. Finally, we studied the protective effects of ZGM1 on cognitive function in APPswe/PS1 mice via behavioral experiments and measured the number of plaques in the mouse brain by thioflavin staining. RESULTS: ZGM1 can bind with Aß directly and mediate a new Aß assembly process to form reticular aggregates and reduce the amount of Aß oligomers. Animal experiments showed that ZGM1 can significantly improve cognitive dysfunction and that Aß plaque deposition in the brain tissue of mice in the drug-administered group was significantly increased. CONCLUSION: Our research suggests that promoting Aß aggregation is a promising treatment method for AD and deserves further investigation.


Assuntos
Encéfalo/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Flavonoides/farmacologia , Placa Amiloide/tratamento farmacológico , Agregados Proteicos/efeitos dos fármacos , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Modelos Animais de Doenças , Flavonoides/uso terapêutico , Camundongos , Camundongos Transgênicos , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Presenilina-1/genética , Resultado do Tratamento
5.
PLoS One ; 12(5): e0177621, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542282

RESUMO

Drought is the one of the most important environment stresses that restricts crop yield worldwide. Cassava (Manihot esculenta Crantz) is an important food and energy crop that has many desirable traits such as drought, heat and low nutrients tolerance. However, the mechanisms underlying drought tolerance in cassava are unclear. Ethylene signaling pathway, from the upstream receptors to the downstream transcription factors, plays important roles in environmental stress responses during plant growth and development. In this study, we used bioinformatics approaches to identify and characterize candidate Manihot esculenta ethylene receptor genes and transcription factor genes. Using computational methods, we localized these genes on cassava chromosomes, constructed phylogenetic trees and identified stress-responsive cis-elements within their 5' upstream regions. Additionally, we measured the trehalose and proline contents in cassava fresh leaves after drought, osmotic, and salt stress treatments, and then it was found that the regulation patterns of contents of proline and trehalose in response to various dehydration stresses were differential, or even the opposite, which shows that plant may take different coping strategies to deal with different stresses, when stresses come. Furthermore, expression profiles of these genes in different organs and tissues under non-stress and abiotic stress were investigated through quantitative real-time PCR (qRT-PCR) analyses in cassava. Expression profiles exhibited clear differences among different tissues under non-stress and various dehydration stress conditions. We found that the leaf and tuberous root tissues had the greatest and least responses, respectively, to drought stress through the ethylene signaling pathway in cassava. Moreover, tuber and root tissues had the greatest and least reponses to osmotic and salt stresses through ethylene signaling in cassava, respectively. These results show that these plant tissues had differential expression levels of genes involved in ethylene signaling in response to the stresses tested. Moreover, after several gene duplication events, the spatiotemporally differential expression pattern of homologous genes in response to abiotic and biotic stresses may imply their functional diversity as a mechanism for adapting to the environment. Our data provide a framework for further research on the molecular mechanisms of cassava resistance to drought stress and provide a foundation for breeding drought-resistant new cultivars.


Assuntos
Desidratação/genética , Desidratação/metabolismo , Manihot/genética , Manihot/metabolismo , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia , Simulação por Computador , Etilenos/metabolismo , Perfilação da Expressão Gênica , Filogenia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Prolina/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Fatores de Tempo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Trealose/metabolismo
6.
Acta Neurol Belg ; 115(1): 59-67, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24865592

RESUMO

The effect of dexamethasone on post-dural puncture headache (PDPH) after spinal anesthesia has not been well elucidated. This randomized, double-blind, placebo-controlled trial was carried out in patients undergoing a cesarean at the Qilu Hospital, Shandong University. The subjects were randomly divided into a placebo and a dexamethasone group. The incidences of PDPH on the first, second, third and seventh postoperative day were studied, and the severity of PDPH was assessed using a visual analog scale. Studies in PubMed, Embase and the Cochrane Library database were searched and included in the present meta-analysis. Summary estimates of weighted mean differences and 95 % confidence intervals (CIs) were obtained using random-effects models. We included 307 participants in the dexamethasone group and 309 in the placebo group for analysis. The results indicated that prophylactic administration of 8 mg dexamethasone did not have any protective effect against PDPH (31 vs. 18, P = 0.054) and even increased the incidence of PDPH in the first 24 h in parturient patients (25 vs. 11, P = 0.016). Furthermore, the meta-analysis also showed that dexamethasone did not prevent the incidence of PDPH in the postoperative follow-up days (RR 1.05; 95 % CI 0.46-2.38; P = 0.91) and may even have increased the trend in the first 24 h. Prophylactic administration of 8 mg dexamethasone does not have any protective effect against PDPH and may even increase the incidence of PDPH in the first 24 h in patients with spinal anesthesia.


Assuntos
Anti-Inflamatórios/uso terapêutico , Dexametasona/uso terapêutico , Metanálise como Assunto , Cefaleia Pós-Punção Dural , Adulto , Raquianestesia/efeitos adversos , Bases de Dados Factuais/estatística & dados numéricos , Método Duplo-Cego , Feminino , Humanos , Incidência , Masculino , Cefaleia Pós-Punção Dural/tratamento farmacológico , Cefaleia Pós-Punção Dural/epidemiologia , Cefaleia Pós-Punção Dural/etiologia , Escala Visual Analógica , Adulto Jovem
7.
Nat Commun ; 5: 3297, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24522756

RESUMO

Twinning on the plane is a common mode of plastic deformation for hexagonal-close-packed metals. Here we report, by monitoring the deformation of submicron-sized single-crystal magnesium compressed normal to its prismatic plane with transmission electron microscopy, the reorientation of the parent lattice to a 'twin' lattice, producing an orientational relationship akin to that of the conventional twinning, but without a crystallographic mirror plane, and giving plastic strain that is not simple shear. Aberration-corrected transmission electron microscopy observations reveal that the boundary between the parent lattice and the 'twin' lattice is composed predominantly of semicoherent basal/prismatic interfaces instead of the twinning plane. The migration of this boundary is dominated by the movement of these interfaces undergoing basal/prismatic transformation via local rearrangements of atoms. This newly discovered deformation mode by boundary motion mimics conventional deformation twinning but is distinct from the latter and, as such, broadens the known mechanisms of plasticity.

8.
Ying Yong Sheng Tai Xue Bao ; 24(8): 2281-6, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24380349

RESUMO

Six soil samples including 3 wilt disease-infected samples and 3 disease-free samples were collected from the banana orchards in 3 areas in Lingao County, Hainan Province of South China. The soil physical and chemical properties were determined by conventional methods, and the diversity of soil bacterial community was analyzed by terminal restriction fragment length polymorphism (T-RFLP). Then, the relationships between the soil bacterial community composition and the soil physical and chemical properties were investigated. In the same areas, most of the soil physical and chemical properties were poorer in disease-infected than in disease-free banana orchards, with the most obvious difference in soil available P content and pH. The T-RFLP analysis showed the diversity of soil bacterial community was richer in disease-infected than in disease-free banana orchards. The lengths of the dominant T-RFs in the 3 areas were 144, 147 and 233 bp, respectively. Through the comparison with phylogenetic assignment tool, it was deduced that the dominant species in the 3 areas were Bacillus subtilis, Staphylococcus and Eubacterium ruminantium. The distribution of most T-RFs was related to the soil alkaline hydrolyzable N, available K, available P and water content, and the relative abundance of most T-RFs was richer in disease-infected than in disease-free banana orchards.


Assuntos
Bactérias/classificação , Biodiversidade , Musa/microbiologia , Doenças das Plantas/microbiologia , Microbiologia do Solo , Bactérias/genética , Bactérias/isolamento & purificação , Consórcios Microbianos
9.
Zhonghua Yi Xue Za Zhi ; 92(29): 2038-41, 2012 Aug 07.
Artigo em Chinês | MEDLINE | ID: mdl-23253804

RESUMO

OBJECTIVE: To conduct long-term follow-ups on the efficacies of surgical approaches for intertrochanteric fractures in elder patients. METHODS: The outcomes of intertrochanteric fractures in 402 elder patients undergoing different surgical procedures during 2005 to 2009 were reviewed. The modified classification of Singh index, detailed surgical contraindications and improved functional scoring system specialized for intertrochanteric fracture were included. Among these, type I to IV had 17 cases (4%), 49 cases (12%), 187 cases (72%), 48 cases (12%). The follow-up period was 1 - 5 years. The orthopedic complications, rehabilitation duration and functional scores were reviewed. RESULTS: Most patients achieved self-care at 1 month post-operation. The failure rate of internal fixation was 5% and infection rate 1.9% in hemiarthroplasty. type I to IV had 70.6% and 100.0%, 85.7% and 86.7%, 85.4% and 92.0%, 72.9% and 87.5% cases showed excellent or good outcomes at 3 month and 1 year. During a follow-up period of 5 years, there was no occurrence of prothetic loosening or excessive wear of acetabular. CONCLUSION: A rational selection of surgical approaches may markedly reduce the failure rate of internal post-operative fixation and shorten the rehabilitation period. And the long-term follow-up outcomes are satisfactory.


Assuntos
Artroplastia de Substituição/métodos , Fixação Interna de Fraturas/métodos , Fraturas do Quadril/cirurgia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Resultado do Tratamento
10.
Huan Jing Ke Xue ; 33(1): 135-41, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22452201

RESUMO

Taking surface sediments from the Wuliangsuhai Lake and Daihai Lake as adsorbent, the isothermal adsorption experiments of silicate on sediments were carried out and the adsorption behavior was explained by Langmuir, Freundlich and Temkin crossover-type equations, then the form distribution characters of silicate were studied after adsorption in this work. The results showed that the adsorption behavior of silicate on the two lakes sediments can be linear fitting in the lower concentration dose (< or = 3.00 mg x L(-1)); the sediments from the Wuliangsuhai Lake behaved adsorbing silicate while the sediments from the Daihai Lake behaved releasing silicate under the experimental dose; all of the Langmuir, Freundlich and Temkin crossover-type equations can be used to explain the adsorption behavior of silicate on the two lakes sediments, and the native adsorption silicate (NAS) and equilibrium silicate concentration (ESC(0)) calculated by the three equations could be used to explain the sink and source effects of the sediments from the two lakes; the silicate form distribution in the sediments after adsorption indicated that silicate adsorbed on particles were mainly added on the form of IEF-Si, CF-Si, IMOF-Si and OSF-Si, and the IMOF-Si and OSF-Si had important potential bioavailability.


Assuntos
Água Doce/análise , Sedimentos Geológicos/química , Silicatos/análise , Silicatos/química , Poluentes Químicos da Água/análise , Adsorção , China , Monitoramento Ambiental , Eutrofização
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(11): 3049-52, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23387177

RESUMO

The Sr3B2O6:Eu(2+) yellow phosphor for warm white LED was synthesized by high temperature solid phase method. The influences on the phosphor structure and luminous properties of sintering temperature and holding time were systematically studied. Results indicated that the optimum synthetic temperature and soaking is 1 150 degrees C and 2 hours respectively. The crystalline structure of phosphor is rhombohedral Sr3B2O6. Sintering temperature and holding time has a significant influence on grain development. The excitation spectrum of phosphor composes of a wide-band spectrum main peaking at 398 nm, and the phosphor can be excited by near ultraviolet and blue light. The luminescence spectrum of phosphor is a broad spectrum peaking at 574 nm. Sintering temperature and holding time have a main effect on luminous intensity of phosphor.

12.
Zhonghua Wei Chang Wai Ke Za Zhi ; 14(12): 948-51, 2011 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-22205455

RESUMO

OBJECTIVE: To evaluate the association between metabolic syndrome and colorectal cancer. METHODS: A multicenter case-control study was conducted. A total of 1506 cases of colorectal cancer (936 males and 570 females), whose clinical data were complete and aged from 30 to 75, were collected in the Third, First and Second People's Hospital of Jingdezhen between 2000 and 2009. A total of 3354 controls (1766 males and 1588 females) were subjects admitted to the above 3 hospitals as cases with acute non-malignant non-digestive diseases. Multiple logistic regression models were used to analyze the association between metabolic syndrome and its components and colorectal cancer. RESULTS: Forty-eight cases of colorectal cancer (3.2%) and 59 controls (1.8%) were diagnosed as metabolic syndrome. Colorectal cancer risk was increased in cases with metabolic syndrome (OR=1.64, 95% CI:1.14-2.49, P<0.05) and in men with metabolic syndrome (OR=1.92, 95% CI:1.27-3.78, P<0.05), but not in women (P>0.05). As the number of component of metabolic syndrome increased, the risk of colorectal cancer increased in men (P<0.01), but not in women (P>0.05). CONCLUSION: Association between metabolic syndrome and colorectal cancer exists in men, but not in women.


Assuntos
Neoplasias Colorretais/etiologia , Síndrome Metabólica/complicações , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Risco , Fatores de Risco
13.
Dalton Trans ; (47): 10609-13, 2009 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-20023886

RESUMO

Reactions of Ln(III) acetate (Ln = Pr and Nd) and a polydentate Schiff-base in a mixture of methanol and acetonitrile resulted in the unprecedented assembly of novel Ln(10) aggregates containing two Ln(5) pentagons templated by mu(5)-CO(3)(2-), introduced via spontaneous fixation of atmospheric carbon dioxide. Magnetic analysis using an expression including the ligand field effects and molecular field approximation indicates weak antiferromagnetic coupling between the metal ions. This synthetic approach may represent a promising new route toward the design of new lanthanide clusters and novel multifunctional materials.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(4): 901-3, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19626868

RESUMO

MgxZn(1-x)O has been subjects of intense attention as a novel photo-electronic functional material in recent years. In the present paper, MgxZn(1-x)O powders were prepared by sol-gel method. Effects of Mg contents on MgxZn(1-x)O structure and luminescence properties were studied. The authors observed that MgxZn(1-x)O exhibited two kinds of structures, hexagonal wurtzite and face center cubic while x was in the range of 0 and 1. The MgxZn(1-x)O powders were hexagonal wurtzite structure with x < 0.2, face center cubic structure with x > 0. 2 and their blend structure with x between 0.2 and 0.8. Luminescence spectrum analysis indicated that all MgxZn(1-x)O samples with various composition showed luminescence of ultra-violet and visible light. The ultraviolet emission peak was from 370 nm to 384 nm and the visible emission peak was around at 468 nm. The average size of MgxZn(1-x)O powders was about 100 nm.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(3): 769-72, 2009 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-19455820

RESUMO

In the present paper, SrS : Eu, Sm phosphors for the broad frequency infrared up-conversion were prepared. XRD analysis indicates that the SrS : Eu, Sm samples calcined at 1 100 degrees C for 1 h exhibit good luminescence properties and they are face-center cubic structure of SrS. Excitation spectrum reveals that the samples can be excited by ultra violet and visible light. Fluorescence spectrum of the samples is composed of four emission peaks at 567 nm, 589 nm, 602 nm and 648 nm respectively. Infrared photo-stimulation luminescence spectrum is a broad-band spectrum peaking at about 595 nm. Infrared response range of the samples is mainly between 800 and 1 400 nm.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(12): 2389-92, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18330267

RESUMO

As a typical optical storage material, CaS : Eu, Sm powders were prepared by wet method in a reduced atmosphere. XRD, emission spectrum, excitation spectrum, photostimulated spectrum, thermal spectrum, and decay curve were measured. The XRD indicates that the lattice of CaS : Eu, Sm was formed at 1050 degrees C. Spectra analysis results show that UV can excite the sample as an information input source. When excited by ultraviolet lamp and then stimulated by 980 nm laser, the same luminescence with peaks at 635 nm. The photostimulated emission decayed rapidly at first and then slowly. The trap level is deep and can make electrons stable in the trap. The optical storage mechanism of CaS : Eu, Sm is discussed.

18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(12): 2399-402, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18330270

RESUMO

Broadband IR-to-visible upconversion material CaS : Ce, Sm was synthesized for the first time by the low-temperature combustion synthesis (LCS) method. The effect of the rare earth dopant concentration on the upconversion properties was studied. XRD analysis shows that the sample features the cubic CaS crystal structure. The excitation spectrum of the sample is in the range of 200-500 nm, i. e. ultraviolet light or the visible light can excite the sample effectively to complete the "charged" process, and the excitation effect of the visible light is dominant. The IR sensitivity spectrum of the sample is in the range of 800-1 400 nm, indicating that CaS : Ce, Sm possesses the broadband IR-to-visible upconversion effect. The IR-to-visible upconversion spectrum of the sample is a broadband spectrum in the range of 450-650 nm, with two adjacent emission peaks at 513.4 and 572 nm, resulting from the transitions of Ce3+2T2g(5d)-->2F5/2 (4f) and the transitions of Ce3+2T2g(5d)-->2F7/2 (4f), respectively.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(11): 1756-9, 2005 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-16499036

RESUMO

A luminosilicate glass samples doped with Eu203 and Dy2O3 were prepared under the air and reducing atmosphere respectively. The excitation spectra, emission spectra and thermal luminescence spectra of the samples prepared under different atmosphere were measured. Luminescence mechanism of the afterglow glasses wa s analyzed. The results showed that the sample prepared under an ambient atmosphere has no afterglow. Its excitation and emission spectra showed the typical transitions of (5)Di( i = 0, 1) --> (7)Fj (j = 0-4) from Eu3+ but the sample reheated at a reducing atmosphere has afterglow. The sample doped with Eu2+ shows luminescence peaking at 462 nm. And the sample codoped with Eu2+ and Dy3+ shows luminescence peaking at 457 nm. The afterglowluminescence can last more than 12 h.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(10): 1560-3, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16395882

RESUMO

Long persistent phosphoresceoce CaAl2O4:Eu2+, Nd3+ nanoparticles were synthesized through sol-gel method. The structures and properties of the samples were analyzed by DTA, TGA, XRD, TEM and spectrometer. Results indicated that the CaAl2O4 crystalline phase was formed at 800 degrees C. The particles are spherical in shape and about 20-40 nm in size. The peaks of the excitation, emission and thermoluminescence spectra shift compared with the CaAl2O4: Eu2+,Nd3+ coarse crystals. The luminescence decay includes a initial rapid part and a following slow part. The decay time lasts for about 5 h.

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