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1.
J Cell Biochem ; 120(7): 12002-12009, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30825242

RESUMO

Pristimerin, a triterpenoid isolated from Celastraceae and Hippocrateaceae, is known to induce cytotoxicity in several cancer cell lines. However, whether pristimerin can induce apoptosis in cholangiocarcinoma cells and the underlying mechanism remain unexplored. We assessed the function of human cholangiocarcinoma QBC and RBE cell lines using various experimental methods such as the cell viability assay to elucidate the viability of cells, flow cytometry to detect the death rate of cells, and Western blot analysis to evaluate the expression of cell cycle-related proteins and autophagy-related proteins. Human cholangiocarcinoma QBC cells were transplanted to nude mice to establish an animal model, and the effect of pristimerin on tumor growth in this model was observed. QBC and RBE cell lines treated with pristimerin (0, 5, 10, and 20 µmol/L) demonstrated the induction of apoptosis in a dose-dependent manner. The cell viability assay revealed a reduction in the cell viability with an increase in the pristimerin concentration. Similarly, flow cytometry revealed a gradual increase in the cell death rate with an increase in the pristimerin concentration. In addition, pristimerin significantly lowered the expression of apoptosis-related proteins (Bcl-2, Bcl-xL, and procaspase-3), but increased the Bax expression. Furthermore, pristimerin resulted in the G0/G1 cell-cycle arrest, reducing the expression of cell cycle-related proteins (cyclin E, CDK2, and CDK4), and increased the expression of autophagy-related proteins (LC3) in QBC cell line. Treatment with pristimerin could inhibit tumor growth in the nude mouse model. Overall, this study suggests the potential effect of pristimerin on the cell-cycle arrest and apoptosis in human cholangiocarcinoma cells.

2.
Hepatobiliary Pancreat Dis Int ; 15(4): 428-33, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27498584

RESUMO

BACKGROUND: Severe acute pancreatitis (SAP) remains a clinical challenge with considerable morbidity and mortality. An early identification of infected pancreatic necrosis (IPN), a life-threatening evolution secondary to SAP, is obliged for a more preferable prognosis. Thus, the present study was conducted to identify the risk factors of IPN secondary to SAP. METHODS: The clinical data of patients with SAP were retrospectively analyzed. Univariate and multivariate logistic regression analyses were sequentially performed to assess the associations between the variables and the development of IPN secondary to SAP. A receiver operating characteristic (ROC) curve was created for each of the qualified independent risk factors. RESULTS: Of the 115 eligible patients, 39 (33.9%) progressed to IPN, and the overall in-hospital mortality was 11.3% (13/115). The early enteral nutrition (EEN) (P=0.0092, OR=0.264), maximum intra-abdominal pressure (IAP) (P=0.0398, OR=1.131) and maximum D-dimer level (P=0.0001, OR=1.006) in the first three consecutive days were independent risk factors associated with IPN secondary to SAP. The area under ROC curve (AUC) was 0.774 for the maximum D-dimer level in the first three consecutive days and the sensitivity was 90% and the specificity was 58% at a cut-off value of 933.5 µg/L; the AUC was 0.831 for the maximum IAP in the first three consecutive days and the sensitivity was 95% and specificity was 58% at a cut-off value of 13.5 mmHg. CONCLUSIONS: The present study suggested that the maximum D-dimer level and/or maximum IAP in the first three consecutive days after admission were risk factors of IPN secondary to SAP; an EEN might be helpful to prevent the progression of IPN secondary to SAP.


Assuntos
Infecções Bacterianas/microbiologia , Pancreatite Necrosante Aguda/microbiologia , Adulto , Área Sob a Curva , Infecções Bacterianas/sangue , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/mortalidade , Biomarcadores/sangue , Progressão da Doença , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Nível de Saúde , Indicadores Básicos de Saúde , Mortalidade Hospitalar , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Pancreatite Necrosante Aguda/sangue , Pancreatite Necrosante Aguda/diagnóstico , Pancreatite Necrosante Aguda/mortalidade , Valor Preditivo dos Testes , Pressão , Prognóstico , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo
3.
Zhonghua Wai Ke Za Zhi ; 51(6): 493-8, 2013 Jun 01.
Artigo em Zh | MEDLINE | ID: mdl-24091261

RESUMO

OBJECTIVE: To investigate the feasibility and clinical value of the step-up approach for severe acute pancreatitis (SAP). METHODS: Clinical data of 121 SAP patients admitted between January 2002 and December 2011 were retrospectively analyzed. Fifty-eight patients (37 males and 21 females, aged from 20 to 72 years, mean 47.6 years) in the group of direct open necrosectomy from January 2002 to December 2006 were performed laparotomy through removal of all necrotic tissue. Sixty-three patients (42 males and 21 females, aged from 19 to 78 years, mean 46.2 years) of step-up approach from January 2007 to December 2011 underwent percutaneous catheter drainage through retroperitoneum or omental bursa guided by B-type ultrasonography for the first therapy, and then, according to the pathogenetic condition, if necessary, followed by a small incisional necrosectomy along the drainage tube. The two groups were compared for the rates of postoperative complications, death, transfusion and length of stay, medical costs. RESULTS: The rates of total postoperative complications, organ dysfunction, alimentary tract fistula and incisional hernia in step-up approach group were significantly lower than those of direct open necrosectomy group (31.7% vs. 62.1%, 14.3% vs. 37.5%, 6.3% vs. 19.0%, 9.5% vs. 29.3%; χ(2) = 4.43 to 11.17, P = 0.001 to 0.035). The other complications had no significant differences between the two groups (P > 0.05). Patients in step-up approach group had a lower rates of transfusion (44.4% vs. 70.7%, χ(2) = 8.488, P = 0.004), fewer medical costs of transfusion and hospital stay, compared with those in direct open necrosectomy group ((2525 ± 4573) yuan vs. (4770 ± 6867) yuan, t = 2.131, P = 0.035; (171 213 ± 50 917) yuan vs. (237 874 ± 67 832) yuan, t = 2.496, P = 0.014). There were no significant differences of length of stay and mortality between two groups (P > 0.05). CONCLUSION: Step-up approach for SAP which can reduce the rates of postoperative complications, transfusion and medical costs has significant feasibility and great clinical value.


Assuntos
Pancreatite Necrosante Aguda/cirurgia , Paracentese , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite Necrosante Aguda/economia , Paracentese/economia , Cavidade Peritoneal/cirurgia , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
4.
Hepatobiliary Pancreat Dis Int ; 11(5): 479-88, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23060392

RESUMO

BACKGROUND: Hemosuccus pancreaticus (HP) is defined as upper gastrointestinal (GI) hemorrhage from the papilla of Vater via the pancreatic duct and is a rare cause of digestive bleeding. DATA SOURCE: A PubMed search of relevant articles published from January 1967 to September 2011 was performed to identify current information about HP in terms of its etiology, pathophysiology, clinical presentation, diagnosis and management. RESULTS: A variety of etiological factors, most commonly chronic pancreatitis but also tumors and vascular diseases, can lead to this condition. Appropriate endoscopic or radiologic procedures should be chosen to establish a precise diagnosis for patients, especially those with a known history of pancreatic disorders, who present with abdominal pain, GI hemorrhage and hyperamylasemia. There are two main therapeutic options for this condition: angiographic embolotherapy and surgery. Both treatments can stop bleeding, but angiographic embolotherapy is the treatment of choice for stable patients. Recently, new and less invasive treatments have emerged to treat this condition. CONCLUSIONS: Because of its rarity and broad spectrum of causes, HP is difficult to diagnose accurately. However, appropriate endoscopic and radiologic procedures are extremely helpful for establishing a correct diagnosis. Both angiographic embolotherapy and surgery are reliable treatment options for this condition, and transcatheter intervention is the treatment of choice for clinically stable patients. Additional innovative treatments have emerged, but their effectiveness and safety must be confirmed.


Assuntos
Ampola Hepatopancreática , Doenças do Ducto Colédoco/etiologia , Hemorragia Gastrointestinal/etiologia , Ductos Pancreáticos , Aneurisma/complicações , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/terapia , Humanos , Neoplasias Pancreáticas/complicações , Pancreatite/complicações
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(7): 1729-33, 2010 Jul.
Artigo em Zh | MEDLINE | ID: mdl-20827958

RESUMO

In the present paper the authors firstly measured the absorption spectra of Er3+ in the sample Er3+ : YVO4 (0.5%), then calculated the intensity parameters are calculated by using the Judd-Ofelt theory. After that the authors dealed with some predicted spectroscopic parameters, such as the oscillator strength, spontaneous radiative transition rate, branching ratio and integrated emission cross section. And Er : YVO4 crystal application value has been analyzed with the optical parameters. Especially there are large oscillator strengths and large integrated emission cross sections in the transitions of 4 I1/2 --> 4 I15/2, 2 H11/2 --> 4I15/2, 4S3/2 --> 4 I15/2, and 4F9/2 --> 4 I15/2. So, they are more worth of attention. Moreover, by comparing the Er-doped yttrium vanadate crystal and other Er-doped crystal optical properties, the authors can see the advantages of YVO4 as laser crystal. Finally, the authors discussed the splitting of the energy levels of Er3+ in the crystal YVO4 based on the group theory.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(8): 1730-3, 2008 Aug.
Artigo em Zh | MEDLINE | ID: mdl-18975790

RESUMO

The upconversion luminescence of nanophase oxyfluoride vitroceramics Tm(0.35)Yb(5) : FOV when excited by a 975 nm diode laser was studied in the present paper. Several ultraviolet upconversion luminescence lines positioned at 363.6 nm, (462.6 nm, 477.0 nm), 648.7 nm, (699.7 nm, 680.7 nm) and (777.6 nm, 800.7 nm) were found. They can be attributed to the fluorescence transitions of 1 D2-->3 H6, 1 G4-->3 H6, 1 G4-->3 F4, 3 F3-->3 H6 and 3 H4-->3 H6 of Tm3+ ion. The careful measurement and analysis of the variation of upconversion luminescence intensity F as a function of the 975 nm pumping laser power P has proven that the upconversion luminescence of 1 D2 state is partly a five-photon upconversion luminescence, while the upconversion luminescence of 1 G4 and 3 H4 state is the three-photon and two-photon upconversion luminescence respectively.

7.
J Zhejiang Univ Sci B ; 7(7): 596-602, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16773736

RESUMO

The effects of dietary supplementation with Clostridium butyricum on growth performance and humoral immune response in Miichthys miiuy were evaluated. One hundred and fifty Miichthys miiuy weighing approximately 200-260 g were divided into five groups and reared in 15 tanks with closed circuiting culture system. The animals were fed 5 diets: basal diet only (control) or supplemented of the basal diet with C. butyricum at doses of 10(3) (CB1), 10(5) (CB2), 10(7) (CB3) or 10(9) (CB4) CFU/g. Compared with the control, the serum phenoloxidase activity was significantly increased by the supplementation (P<0.05), acid phosphatases activity was increased significantly (P<0.05) at the doses of 10(9) CFU/g. Serum lysozyme activity peaked at dose of 10(7) CFU/g and in the skin mucus at dose of 10(9) CFU/g. Immunoglobulin M level in the serum and skin mucus was increased except at dose of 10(3) CFU/g (P<0.05). The growth at the dose of 10(9) CFU/g was higher than that of the control (P<0.05). It is concluded that supplementation of C. butyricum can mediate the humoral immune responses and improve the growth performance in Miichthys miiuy.


Assuntos
Ração Animal/microbiologia , Formação de Anticorpos/fisiologia , Clostridium butyricum/imunologia , Suplementos Nutricionais/microbiologia , Peixes/crescimento & desenvolvimento , Peixes/imunologia , Probióticos/administração & dosagem , Animais
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(5): 869-73, 2006 May.
Artigo em Zh | MEDLINE | ID: mdl-16883857

RESUMO

Breast tissue sections were examined by means of confocal Raman spectroscopy with an excitation wavelength of 633 nm. Acquired using a microscopic mapping approach with the sample volume of -2 microm3, these spectra were compared with the ones of the commercially available actin, DNA, collagen (type I), triolein etc. Some spectra were distinguished and identified and characterize the morphological elements like cell cytoplasm, extracellular matrix etc. The cell nucleus spectrum was also obtained by K-means cluster analysis. The correlation analysis showed that the spectrum from a morphological element is highly correlated with that from the corresponding purified chemical. The spectroscopic characterization of these morphological elements was then investigated. This study is helpful to understanding the chemical/morphological basis of the Raman spectrum and designing the Raman microspectroscopic model of human breast tissue.


Assuntos
Neoplasias da Mama/química , Mama/química , Microscopia Confocal/métodos , Análise Espectral Raman/métodos , Mama/anatomia & histologia , Núcleo Celular/química , Colágeno Tipo I/análise , Citoplasma/química , Matriz Extracelular/química , Feminino , Humanos
9.
J Zhejiang Univ Sci B ; 6(8): 798-802, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16052714

RESUMO

Effects of dietary supplementation with fructooligosaccharides on the excretion of nitrogen and phosphorus in Miichthys miiuy fries were investigated. Nine hundred Miichthys miiuy fries were divided into 3 groups, each with triplicates. The basal diet and the basal diet supplemented with carnitine groups were considered as the negative and positive controls respectively. Results showed that the nitrogen concentration in excreted feces decreased significantly in fries fed the diet supplementation with 1000 x 10(-6) fructooligosaccharides and 200 x 10(-6) carnitine (P<0.05). The ammonic-nitrogen concentration decreased significantly in the carnitine group only (P<0.05), indicating the decreasing tendency caused by the supplementation with fructooligosaccharides. Supplementation with both did not have significant effects on the concentration of phosphorus in feces of Miichthys miiuy fries.


Assuntos
Suplementos Nutricionais , Fezes , Peixes/metabolismo , Nitrogênio/metabolismo , Oligossacarídeos/administração & dosagem , Fósforo/metabolismo , Administração Oral , Animais
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(2): 161-5, 2005 Feb.
Artigo em Zh | MEDLINE | ID: mdl-15852845

RESUMO

The saturation phenomenon of the up-conversion luminescence of erbium ytterbium co-doped oxyfluoride vitroceramics (ErYb:FOV), when excited by a 966 nm diode-laser, was investigated comprehensively in the present article. A new kind of "characteristic saturation phenomenon", which results from energy diffusion, was found, i. e. the slope of logI-logP curve, the double logarithmic variation of up-conversion luminescence intensity I upon laser power P, is increased evidently toward regular multi-photon relation with the increase of laser facula. The "typical saturation phenomenon" resulting from ground state population's exhaustion has huge influence as well, which causes these logI-logP curves to bend gradually with the increase in laser power. Interestingly, this "typical saturation phenomenon" can be decreased obviously and even vanishes when the pumping laser power density is decreased enough.


Assuntos
Cerâmica/química , Érbio/química , Flúor/química , Luminescência , Óxidos/química , Itérbio/química , Absorção , Transferência de Energia , Lasers , Medições Luminescentes/métodos , Modelos Químicos , Espectrometria de Fluorescência
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(1): 13-8, 2005 Jan.
Artigo em Zh | MEDLINE | ID: mdl-15852807

RESUMO

The volumetric display technology is one of the important science frontiers of modern society. Multi-photon up-conversion volumetric 3-D display, attractive especially in its self-spatial vision, has the advantages of total-solidification, high reliability and speedy operation so that it has a broad range of applications. The up-conversion luminescence of oxyfluoride glass material Er(0.5): FOG, when excited by 1 520 nm semiconductor laser, was studied. The common-fluorescence spectra were measured also, in order to know up-conversion sufficiently. It was found that there are several up-conversion luminescence lines (407.43, 411.20 nm), (522.51(m), 528.57 nm), (540.53(m), 543.70, 549.00 nm), (654.75(m), 665.50 nm) and 802.10(m) nm, which can be recognized as the fluorescence-transitions of (2G4F2H)9/2 --> 4 I15/2, 4H11/2 --> 4 I15/2, 4S3/2 --> 4 I15/2, 4F9/2 --> 4I15/2 and 4I9/2 --> I15/2 respectively. It is interesting that the slopes of log F-log P curves, the double logarithmic variation of up-conversion luminescence intensity F with the laser power P, are various for these observed up-conversion luminescences, which are valuable for volumetric display. The comprehensive analysis found that the (2G4F2H)9/2 --> 4I15/2 up-conversion luminescence is a four photon up-conversion luminescence, while [2 H11/2 --> 4I15/2, 4S3/2 --> 4I15/2 and 4F9/2 --> 4I15/2] up-conversion luminescence is three-photon up-conversion luminescences, and 4I9/2 --> 4I15/2 up-conversion luminescence is a two-photon up-conversion luminescence. It was found also that the absorption from the ground-state 4I15/2 level to first excited level is very large, resulting in the fact that the sequential energy transfer and step-by-step absorption up-conversion are readily to happen.


Assuntos
Flúor/química , Lasers Semicondutores , Luminescência , Medições Luminescentes/métodos , Óxidos/química , Transferência de Energia , Vidro , Imageamento Tridimensional , Medições Luminescentes/instrumentação , Espectrometria de Fluorescência
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(6): 912-5, 2005 Jun.
Artigo em Zh | MEDLINE | ID: mdl-16201370

RESUMO

The Human Serum Albumin (HSA) can emit fluorescence (lamda(em) = 350 nm) under irradiation of ultraviolet light (lamda(ex) = 296 nm). After the vitamin B6 (B6) was added into HSA solution the fluorescence of HSA was quenched partially. This quenching was static quenching owing to the fact that ro (fluorescence life time (life time of the molecule excitation state) of HSA without B6) equaled to tau(i) (fluorescence life time of HSA with B6). The formation constant K between HSA and B6 was observed from the experiment, and then the binding distance R0 was determined (R0 = 1.872 nm). The CD spectra of samples (HSA, [HSA] = 1 x 10(-5) mol x L(-1), HSA +B6, [B6] = 5 x 10(-8), 1.5 x 10(-7), 2.5 x 10(-7), 3.5x 10(-7), 4.5x 10(-7) mol x L(-1)) were measured, and all CD spectra were almost the same. From [theta] values, the contents (percent content) of four structure(alpha-Helix, beta-Pleated, Beta-corner, and Randon wind) of samples can be calculated, and we find that all samples contain almost the same structure contents.


Assuntos
Fluorescência , Albumina Sérica/química , Vitamina B 6/química , Algoritmos , Sítios de Ligação , Dicroísmo Circular , Humanos , Cinética , Modelos Químicos , Ligação Proteica , Albumina Sérica/metabolismo , Espectrometria de Fluorescência , Vitamina B 6/metabolismo
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(2): 232-4, 2005 Feb.
Artigo em Zh | MEDLINE | ID: mdl-15852863

RESUMO

Fluorescence spectroscopy has achieved great successes in the study on the interaction of drugs and DNA in both quantitative analysis and qualitative analysis. While the fluorescence probe technique can be used to measure the intensity of drugs-DNA interaction, because the injected drugs can change the fluorescence intensity of the probe. In this paper, the authors use berberine as a probe to measure the interaction intensity between some anticancer drugs and DNA, calculate the constant D and determine the effects of those drugs. In addition, the authors point out that this method can not be efficient for certain drug solution.


Assuntos
Antineoplásicos/química , Berberina/química , DNA/química , Espectrometria de Fluorescência/métodos , Fluoruracila/química , Cinética , Mitomicinas/química , Reprodutibilidade dos Testes
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(3): 426-30, 2003 Jun.
Artigo em Zh | MEDLINE | ID: mdl-12953505

RESUMO

The direct sensitization upconversion luminescence phenomenon of Ho(0.5)Yb(5) co-doped oxyfluoride glass was studied. There are two strong upconversion luminescence lines positioned at (544.5 nm, 18,365 cm-1) and (658.5 nm, 15,186 cm-1), which are the transitions of 5S2-->5I8 and 5F5-->5I8. There are others upconversion luminescence lines, which are 5F3-->5I8, 5S2-->5I7 and 5I4-->5I8. An evident characteristic saturation phenomenon is found also. That is all the F-P log-log curves of upconversion fluorescence vs. pumping laser power are rather good straight lines. Its slope will increase with enhancement of pumping laser facula. This is mainly caused by energy diffusion among Yb3+ ions.


Assuntos
Flúor/química , Vidro/química , Hólmio/química , Óxidos/química , Itérbio/química , Luminescência , Fotoquímica , Espectrometria de Fluorescência
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(11): 1359-62, 2004 Nov.
Artigo em Zh | MEDLINE | ID: mdl-15762476

RESUMO

The microscopic Raman spectra from normal and malignant human breast tissues have been measured and investigated. The spectral differences and changes between normal and malignant breast tissue samples mainly involve: (1) the band from the symmetric stretching modes of PO2- group in the DNA shifts from 1082 to 1097 cm(-1) and becomes stronger. The intensity of the symmetric stretching modes of O-P-O at 817 cm(-1) in RNA increases greatly. (2) The bands of Amide I and III at 1657 and 1273 cm(-1) change to 1662 and 1264 cm(-1) respectively with their intensity and band width increasing. The peak of the C-O stretching modes in the amino acids shifts to higher wave number. The tryptophan band at 1368 cm(-1) almost disappears. (3) Fewer characteristic Raman bands from lipids are observed. These spectral changes indicate that nucleic acids increase in contents relatively, while their conformation changes in cancer tissues. The proteins show various conformations and disorder structures with their molecular hydrogen bonds nearly broken. The contents of lipids decrease obviously. This investigation shows that Raman microspectroscopy is useful to biochemical study and vivo diagnosis of human breast cancers.


Assuntos
Amidas/química , Neoplasias da Mama/diagnóstico , DNA/química , Diagnóstico Diferencial , Lipídeos/química , Proteínas de Neoplasias/química , Análise Espectral Raman/métodos , Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Feminino , Humanos , Ligação de Hidrogênio , Lipídeos/análise , Ácidos Nucleicos/química , Conformação Proteica
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(1): 1-5, 2003 Feb.
Artigo em Zh | MEDLINE | ID: mdl-12939953

RESUMO

This paper investigates the direct upconversion sensitization luminescence of the ErYb co-doped oxyfluoride glass (ErYb: FOG), fluoride glass (ErYb: ZBLAN) and pentaphosphate noncrystalline (ErYb: PP) excited by a 966 nm diode laser. The splendid upconversion luminescence phenomenon is found. It is resulted from that the Yb3+ concentration in rather high, the energy transfer among Er(3+)-Yb3+ and Yb(3+)-Yb3+ ions is rather strong. An important fact is found that the direct upconversion sensitization luminescence of ErYb: FOG is about 100-100,000 times greater than that of ErYb: PP. And meanwhile it is interesting that the upconversion luminescence intensity of ErYb: FOG is near to that of ErYb: ZBLAN. It is significant to enhance the comprehensive level of up-conversion luminescence.


Assuntos
Érbio/química , Luminescência , Itérbio/química , Transferência de Energia , Fluorescência , Fluoretos/química , Flúor/química , Vidro/química , Óxidos/química , Fosfatos/química , Fotoquímica/métodos , Semicondutores , Análise Espectral/métodos
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(3): 431-4, 2003 Jun.
Artigo em Zh | MEDLINE | ID: mdl-12953506

RESUMO

This paper investigates one-beam pumping up-conversion three-dimensional volumetric display, which is based on a Er:ZBLAN fluoride glass. The light-length of the facula of one-beam up-conversion luminescence was studied by a 966 nm semiconductor laser. The up-conversion luminescence spectrum was also obtained. It was found that the property of one-beam pumping three-dimensional volumetric display can be improved significantly by 1.52 microns LD laser multi-photon up-conversion, this finding has not been reported.


Assuntos
Apresentação de Dados , Érbio/química , Fluoretos/química , Óxidos/química , Fluorescência , Vidro/química , Fotoquímica/métodos
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 22(4): 529-34, 2002 Aug.
Artigo em Zh | MEDLINE | ID: mdl-12938355

RESUMO

Recently, in virtue of the develop of the semiconductor laser and the doped laser materials with rare-earth ions, the up-conversion laser with resonant pump has became a scientific subject in great demand. The doped oxyfluoride glass ceramic with rare-earth ions is a very excellent material, its optical property and chemical stability are outstanding. So, absorption spectrum of Er3+ in Fluoroxide glass ceramic was measured, and intensity parameters omega lambda were calculated using Judd-Oflet theory. Some predicted spectroscopic parameters of the excited states, like the spontaneous radiative transition rate, branching ratio and integrated emission cross section were given.


Assuntos
Érbio/química , Flúor/química , Óxidos/química , Itérbio/química , Cerâmica/química , Fenômenos Químicos , Físico-Química , Vidro/química , Lasers , Teste de Materiais , Fotoquímica , Espectrometria de Fluorescência , Espectrofotometria/métodos
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(2): 209-12, 2003 Apr.
Artigo em Zh | MEDLINE | ID: mdl-12961850

RESUMO

Spectral characteristics of an organic material in acid with different concentrations were investigated in the solution of a proper acid concentration. The results showed that at 252 nm the transmittance T = 56.5%, but at 290 nm the material had a strong absorption peak (epsilon > 10(4) L. (mol.cm)-1). The absorbance A280-298 nm > 8, i.e. T280-298 nm < 10(-8). The band width was about 16 nm. Therefore, this material has conspicuous characteristics such as high transmittance and deep cutoff in the background in ultraviolet-c band. The transmission peak can be shifted in the range of 251-260 nm by changing the pH value of the solution and selecting solution with a different polarity. By analyzing the spectra of the material in acid we found that the two original absorption peaks disappeared, and a new strong absorption peak appeared at 290 nm. Moreover, it seems to be some relation between the two absorption peak intensity and the new peak, which needs to be further studied. Using this result, we can produce high quality UV-filters of this material with traditional coating and colour glass technology.

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