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1.
Zoolog Sci ; 41(2): 210-215, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38587916

RESUMO

Protocobitis species are typical cave-dwelling fish, exhibiting distinctive morphological adaptations such as colorless body, lack of eyes, and reduced scales and ribs in response to their extreme cave habitats. Distinct from the recorded species, P. anteroventris, P. polylepis, and P. typhlops, a new species, Protocobitis longicostatus sp. nov., is described from Guangxi Zhuang Autonomous Region, China. Protocobitis longicostatus sp. nov. can easily be distinguished from all known congeners by the following characteristics: whole body covered by scales except head, 12 branched caudal fin rays, and long ribs. These species face threats from habitat degradation, hydrological changes, and environmental pollution. Thus, the conservation of cavefish in China has become an urgent issue.


Assuntos
Cipriniformes , Animais , Cipriniformes/anatomia & histologia , China , Cavernas , Olho , Ecossistema
2.
J Minim Access Surg ; 17(3): 287-293, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33047686

RESUMO

AIM: Robotic gastrectomy (RG) is more and more widely used in the treatment of gastric cancer. However, the long-term oncological outcomes of RG have not been well evaluated. The aim of this study was to evaluate the long-term oncological outcomes of RG and laparoscopic gastrectomy (LG) in the treatment of gastric cancer. MATERIALS AND METHODS: PubMed, China National Knowledge Infrastructure, Cochrane Library and EMBASE electronic databases were searched until August 2019. Eligible studies were analysed for comparison of oncological outcomes between RG and LG in patients with gastric cancer. RESULTS: Eleven retrospective comparative studies, which included 1347 (32.52%) patients in the RG group and 2795 (67.48%) patients in the LG group, were selected for the analysis. Meta-analysis of the 11 included studies showed that there was no statistically significant difference in the OS between the RG and LG groups (hazard ratios [HRs] = 0.97, 95% confidence intervals [CIs] = 0.80-1.19, P = 0.80). Six studies evaluated disease-free survival (DFS), and pooled analysis showed that there was no statistically significant difference in DFS between RG group and LG group (HR = 0.94, 95% CIs = 0.72-1.23, P = 0.65). According to the odds ratio (OR) analysis, there was no significant difference in 3-year OS, 5-year OS, 3-year DFS and 5-year DFS between the RG and LG groups. Nine articles reported the recurrence rate, and the meta-analysis showed that there was no statistically significant difference between the RG and LG groups (OR = 0.88, 95% CIs = 0.69-1.12, P = 0.31). CONCLUSIONS: This meta-analysis indicated that the long-term oncological outcomes in the RG group were similar to that in the LG group.

3.
Yao Xue Xue Bao ; 46(4): 395-9, 2011 Apr.
Artigo em Zh | MEDLINE | ID: mdl-21751492

RESUMO

This study is to investigate the protective effects of the SB203580 against radiation induced mortality and intestinal injury of mice. A total of 67 male C57BL/6 mice (20.0-22.0 g) were matched according to body weight and randomly assigned to one of three groups: control, total body irradiation exposure (IR, 7.2 Gy) only, and IR (7.2 Gy) + SB203580 (15 mg x kg(-1)). 30 days survival rate was observed in the experiment. In intestinal injury experiment, the expression levels of caspase-3, Ki67, p53 and p-p38 were assayed in the mice intestine crypts. The results showed that the 30 days survival rate was 100% (control), 0 (IR) and 40% (IR+ SB203580), separately. Compared to the IR groups, the positive cells of caspase-3, p53 and p-p38 in crypt cells decreased 33.00%, 21.78% and 34.63%, respectively. The rate of positive cells of Ki67 increased 37.96%. Significant difference was found between all of them (P < 0.01). SB203580 potently protected against radiation-induced lethal and intestinal injury in mice, and it may be a potential radio protector.


Assuntos
Apoptose/efeitos da radiação , Imidazóis/farmacologia , Intestinos/efeitos dos fármacos , Piridinas/farmacologia , Lesões Experimentais por Radiação , Protetores contra Radiação/farmacologia , Animais , Caspase 3/metabolismo , Inibidores Enzimáticos/farmacologia , Mucosa Intestinal/metabolismo , Intestinos/patologia , Antígeno Ki-67/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/mortalidade , Lesões Experimentais por Radiação/patologia , Distribuição Aleatória , Proteína Supressora de Tumor p53/metabolismo , Irradiação Corporal Total , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
4.
Infect Disord Drug Targets ; 19(1): 17-29, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30101721

RESUMO

The constant Ebola epidemic outbreaks in Africa arisen in waves of panic worldwide. There is a high mortality rate (30-70%) among the Ebola-infected people in virus- stricken areas. Despite these horrors, the medical capabilities against this deadly viral disease were provided by limited therapeutic agents/options. As a result, several patented agents, biotherapies or prophylactic/therapeutic vaccines need to be reviving into the global markets-including patents of small molecular chemicals, short sequences or oligomers of DNA/RNA, linkages of chemicals with bio-molecules, herbal medicine and so on. In addition, the possible mechanisms of action of these therapeutic options are underway. To promote Ebola biomedical study, the multiple characters of Ebola infections-its origin, pathologic progress, genomic changes, therapeutic context and economic considerations are outlined in this review. Finally, a great difference can be expected after these types of efforts.


Assuntos
Antivirais/uso terapêutico , Ebolavirus/patogenicidade , Doença pelo Vírus Ebola/terapia , Vacinas Virais/uso terapêutico , África/epidemiologia , Surtos de Doenças/prevenção & controle , Ebolavirus/efeitos dos fármacos , Ebolavirus/imunologia , Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/virologia , Humanos , Taxa de Sobrevida , Vacinas Virais/imunologia
5.
Cent Nerv Syst Agents Med Chem ; 19(1): 15-23, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30644350

RESUMO

The article entitled "Human Suicide, Modern Diagnosis Assistance and Magic Bullet Discovery", by Da-Yong Lu, Peng- Peng Zhu, Hong-Ying Wu, Nagendra Sastry Yarla, Bin Xu, Jian Ding, Ajit Varki and Ting-Ren Lu, has been retracted on the request of the co-authors, Dr. Ajit Varki, Dr. Nagendra Sastry Yarla and Dr. Jian Ding available at: Cent Nerv Syst Agents Med Chem 2019; 19(1): 15-23. http://www.eurekaselect.com/169003/article.The Corresponding Author Dr. Da-Yong Lu has included the names of the co-authors, Dr. Ajit Varki, Dr. Nagendra Sastry Yarla and Dr. Jian Ding without their consent and the manuscript has been published in the journal, Central Nervous System Agents in Medicinal Chemistry (CNSAMC). Kindly see Bentham Science Policy on Article retraction at the link given below:(https://benthamscience.com/journals/central-nervous-system-agents-in-medicinal-chemistry/author-guidelines/)Submission of a manuscript to the respective journals implies that all authors have read and agreed to the content of the Copyright Letter or the Terms and Conditions. As such, this article represents a severe abuse of the scientific publishing system. Bentham Science Publishers takes a very strong view on this matter and apologizes to the readers of the journal for any inconvenience this may cause.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(12): 2781-4, 2008 Dec.
Artigo em Zh | MEDLINE | ID: mdl-19248482

RESUMO

Using the gel-combustion method the precursors of GaLa(1-x)Al3O7 : xEu3+ (0.05 < or = x < or = 0.8) were prepared. When annealing temperature was below 700 degrees C, the materials were in amorphous state, while as annealing temperature was above 800 degrees C, the high purity CaLa(1-x)Al3O7 : xEu3+ crystalline materials were obtained. The luminescence properties of GaLa(1-x)Al3O7 : xEu3+ both in amorphous and crystalline phases were investigated, and the results of excitation spectrum show a similar charge transition band of Eu3+--O2- between 230 nm and 320 nm and a series of f--f transition of Eu3+ ion. However, the strongest band of amorphous material was at 465 nm corresponding to (7)F0--(5)D2 transition, and those of the crystalline materials were at 394 nm corresponding to (7)F0--(5)L6 transition of Eu3+ ion. In amorphous state materials the emission intensity of excitation wavelength 465 nm was stronger than that of 394 nm, and composition of (5)D0--(7)F0 transition at 578 rim, (5)D0--(7)F1 transition at 587 rim and (5)D0--(7)F2 transition at 615 rim. In crystalline material, the emission intensity of excitation wavelength of 394 run was stronger than that of 465 rim, the (5)D0--(7)F0 transition disappeared, and the (5)D0--(7)F1 transition split into 587 rim and 596 rim. With the increase in temperature, the strongest band at 615 rim increased, and what is more, the (5)D0--(7)F1 transition increased remarkably. In CaLa(1-x)Al3O7 : xEu3+, when x=0.2 for the co-doping Eu3+ ion and the mol proportion of citric acid and metal ion (C/M) was 1.2, the luminescence intensity was the highest.

7.
Infect Disord Drug Targets ; 18(1): 15-22, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28474549

RESUMO

AIDS (acquired immune deficient syndrome) is a deadly human viral infectious disease caused by HIV (human immune-deficient virus) infection. Almost every AIDS patient losses his/her life before mid 1990s. AIDS was once the 1st disease killer in US (1993). After one decade hard work, antiviral drug cocktails-high active anti-retroviral therapy (HAART) have been invented for almost all HIV infection treatments. Due to the invention of HAART, 80-90% HIV/AIDS patients still effectively response to HAART for deadly AIDS episode controls and life saving. Yet, this type of HIV therapeutics is incurable. HIV/AIDS patients need to take HAART medications regularly and even life-long. To counteract this therapeutic drawback, more revolutionary efforts (different angles of therapeutic modes/attempts) are urgently needed. In this article, the major progresses and drawbacks of HIV/AIDS chemotherapy (HAART) to HIV/AIDS patients have been discussed. Future trends (updating pathogenesis study, next generations of drug developments, new drug target discovery, different scientific disciplinary and so on) are highlighted.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade/tendências , Descoberta de Drogas/tendências , Infecções por HIV/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/virologia , Fármacos Anti-HIV/isolamento & purificação , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Química Farmacêutica/métodos , Reservatórios de Doenças/virologia , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Masculino , Farmacogenética/métodos , Farmacogenética/tendências
8.
Cent Nerv Syst Agents Med Chem ; 18(3): 206-212, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30117402

RESUMO

INTRODUCTION: Suicide is still a major event of human mortality worldwide. Yet human suicide prediction, prevention and therapeutic systems at this moment are generally ineffective in the clinic. No diagnostic system is reliable for significantly suicidal prevention and mortality reduction. As a result, human suicide etiopathologic investigation (especially at genetic/molecular levels in the clinical settings) is quite necessary. In order to boost human suicide researches, emerging human suicide diagnostic/treatment study will be transformed from clinical symptom observations into new generations of candidate drug targets and therapeutics. To achieve this goal, associations between suicidal etiopathologic identification, genetic/bioinformatics-based diagnostics and putative drug targets must be exploited than ever before. After all, the interaction and relationships between environmental/ genetic/molecular clues and overall patient's risk prediction (environmental influences and different therapeutic targets/types) should be found out. CONCLUSION: In the future, effective clinical suicide prediction, prevention and therapeutic systems can be established via scientific expeditions and causality discovery.

9.
Recent Pat Antiinfect Drug Discov ; 13(3): 217-227, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30362422

RESUMO

BACKGROUND AND AIMS: AIDS (acquired immune deficient syndrome), a deadly human infectious disease is caused by HIV (human immunodeficiency viruses) infection. Patient's mortality was eventually reduced to one-fourth by combined chemotherapy (usually 3 chemical drugs simultaneously) than earlier HIV/AIDS treatments (single drug or vaccine) in the clinic. RESULTS: Combined treatments against HIV/AIDS are still incurable for all patients despite a high rate of patient's survival. Basic viral pathological study and advancing drug development systems for curable medications are indispensable nowadays and in the future. CONCLUSION: Up to date, therapeutic trinity (combined therapy) against HIV/AIDS is generally among chemical drugs. In this article, several forms of other therapeutic attempts for effectively curing efforts against HIV/AIDS are proposed-including the development of next generation therapeutic HIV vaccines and schedules, new categories of bio-therapy, different pathways of immune-modulation, herbal medicines in general (allopathic, Ayurveda and traditional Chinese medicines), high quality of physical exercises, and especially therapeutic combinations guided by latest medical discovery and principles (new forms of therapeutic trinity against HIV-induced pathogenesis and human mortality).


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Terapia Biológica/métodos , Terapia por Exercício/métodos , Infecções por HIV/terapia , Medicina Tradicional/métodos , Vacinas contra a AIDS/uso terapêutico , Fármacos Anti-HIV/uso terapêutico , Terapia Combinada/métodos , HIV/efeitos dos fármacos , HIV/imunologia , HIV/isolamento & purificação , Infecções por HIV/imunologia , Infecções por HIV/mortalidade , Infecções por HIV/virologia , Humanos , Taxa de Sobrevida , Resultado do Tratamento
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(5): 991-4, 2007 May.
Artigo em Zh | MEDLINE | ID: mdl-17655121

RESUMO

The excitation and emission spectra of seven Tb3+ complexes were measured and investigated, especially by comparing their fluorescence intensities. The effect of different ligands on the fluorescence intensity of Tb3+ was analyzed in terms of ligand structure, energy transfer and energies matching. The result indicates that ligands do not influence the positions of characteristic emission peaks of Tb3+, but the emission intensity. The research shows that the better the conjugative effect and rigidity of the ligand, the stronger the fluorescence intensity of the complex. In addition, binary acid strengthens the fluorescence intensity more efficiently than monoatomic acid. Eventually, the IR and Raman spectra of seven complexes of Tb were discussed.

11.
Rev Recent Clin Trials ; 12(2): 101-110, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28190390

RESUMO

BACKGROUND: Last two to three decades, this world witnesses a rapid progress of biomarkers and bioinformatics technologies. Cancer bioinformatics is one of such important omics branches for experimental/clinical studies and applications. METHODS: Same as other biological techniques or systems, bioinformatics techniques will be widely used. But they are presently not omni-potent. Despite great popularity and improvements, cancer bioinformatics has its own limitations and shortcomings at this stage of technical advancements. RESULTS: This article will offer a panorama of bioinformatics in cancer researches and clinical therapeutic applications-possible advantages and limitations relating to cancer therapeutics. A lot of beneficial capabilities and outcomes have been described. As a result, a successful new era for cancer bioinformatics is waiting for us if we can adhere on scientific studies of cancer bioinformatics in malignant- origin mining, medical verifications and clinical diagnostic applications. CONCLUSION: Cancer bioinformatics gave a great significance in disease diagnosis and therapeutic predictions. Many creative ideas and future perspectives are highlighted.


Assuntos
Antineoplásicos/farmacologia , Biologia Computacional/métodos , Terapia de Alvo Molecular/métodos , Neoplasias/tratamento farmacológico , Medicina de Precisão/métodos , Antineoplásicos/uso terapêutico , Pesquisa Biomédica/métodos , Feminino , Humanos , Masculino , Neoplasias/genética , Sensibilidade e Especificidade
12.
Anticancer Agents Med Chem ; 17(1): 21-28, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27039923

RESUMO

Many clinical cancer therapies are less effective by using one anticancer drug only due to refractory properties of cancer pathogenesis and drug resistance property in advanced cancer patients. A general consensus among clinicians is that anticancer drug cocktail might better control cancer progresses and metastasis than single drug therapeutics in clinical trials. Despite great popularity, the anticancer drug combination dogma has not been established. The complexity of drug combination dogma discovery is more than we can expect now. This article speculates possible routes we can undertake in this matter. The background knowledge of drug combination therapy presently practiced and possible future landscapes and drawbacks of cancer drug combinative therapies are highlighted.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Resistencia a Medicamentos Antineoplásicos , Humanos , Medicina de Precisão/métodos
13.
Rev Recent Clin Trials ; 12(3): 202-211, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28782482

RESUMO

AIM: The modality of anticancer drug combinations needs to be renovated from empirical into technical-supportive systems. METHODS: To challenge past therapeutic routines, the new landscape may be established. Among the different areas of anticancer drug combination study, research in the fields of medical study is the most important one-including disciplinary of therapeutics in different cancer stages, modern genetic/ molecular diagnostics, cancer bioinformatics, traditional Chinese medicine, mathematical data analysis, therapeutic toxicity monitor, personalized cancer medicine and so on. DISCUSSION: This article addresses these types of cancer therapeutic management systems for clinical anticancer drug combination utilities. CONCLUSION: Future cancer drug combinational studies and clinical optimums must be implemented.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , Medicina de Precisão/métodos , Humanos , Estadiamento de Neoplasias , Neoplasias/patologia
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(5): 805-8, 2006 May.
Artigo em Zh | MEDLINE | ID: mdl-16883841

RESUMO

Eu3+ Complexes with benzoic acid and 1,10-phenanthroline incorporated in SiO2, SiO2-B2O3 and SiO2-B2O3-Na2O matrices were prepared via the sol-gel method. Eu-doped SiO2, SiO2-B2O3 and SiO2-B2O3-Na2O luminescence materials were synthesized. The luminescence of Eu3+ was studied with excitation spectra and emission spectra. Different forms of dopants could influence the luminescence properties. The structure of Eu-doped glass was studied by comparing IR, TEM and XRD. The results showed that after the materials were annealed at 1 000 degrees C the structure was very stable because ingredient was already removed totally. The emission spectrum showed that the typical optical spectrum of Eu3+ is 5D0 --> 7Fj (j = 1, 2) at 588 nm and 614 nm. Comparing EuCl3 with Eu3+ complexes with benzoic acid and 1,10-phenanthroline as dopant, the latter has strong luminescence property though it has small mass fraction. The luminescence intensity of Eu(3+)-doped SiO2-B2O3 glass material was weaker than that of Eu(3+)-doped SiO2 glass material, and the former's spectrum showed that there were Si-O-B bonds. The luminescence intensity of Eu3+ was quenched by this kind of structure. The luminescence intensity of Eu(3+)-doped SiO2-B2O3-Na2O glass material was greatly increased, and the infrared spectrum illustrated that there was not vibration absorption of Si-O-B bonds. Probably Na replaced B, and Si-O-Na bonds formed. This kind of structure could enhance luminescence intensity of Eu3+ to some extend.

15.
Rev Recent Clin Trials ; 11(2): 145-51, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26672600

RESUMO

After long defeats-almost no marked breakthrough in HIV vaccination campaign has been observed during the past two decades, and we still have not lost our faiths for the development of highly effective and low risk HIV vaccines. Many effective vaccines have been discovered and will certainly enter into the markets within the next 5 to 10 years. In order to promote HIV vaccine developments and clinical HIV therapeutic improvements, this perspective addresses the good and bad sides of currently available HIV vaccines, discusses many subjects of medical significance and finally provides up-to-date information in the field of HIV studies, in particular regarding vaccine developments and HIV pathogenesis.


Assuntos
Vacinas contra a AIDS , Infecções por HIV/prevenção & controle , Humanos , Vacinação
16.
Rev Recent Clin Trials ; 11(4): 290-296, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27480966

RESUMO

HIV/AIDS was once a highly deadly infective disease that killed the global people of a million annually two decades ago. While we are enjoying the HIV therapeutic advances (mostly important from HAART invention), one obvious drawback is still unresolved-unable to clearance all HIV from infected human bodies. As a result, a series of different therapeutic attempts have been proposed based on present knowledge of different features of HIV-induced pathogenesis and human mortalities. Facing this shortcoming, innovative designs and update of HIV vaccines and other types of HIV therapeutic inventions can be a final solution for completely HIV clearance and infection managements in human beings. Owing to these scientific and medical significances, several experimental and clinical attempts have to be made. Among these attempts, part of them (updating HIV vaccine developments and clinical routines) are quite promising and noteworthy. In this article, we offer the general information of this attempt and discuss it separately, especially on the respects of HIV vaccine strategic innovations.


Assuntos
Vacinas contra a AIDS , Infecções por HIV/prevenção & controle , Humanos
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(3): 428-31, 2005 Mar.
Artigo em Zh | MEDLINE | ID: mdl-16013324

RESUMO

Some novel binary and ternary complexes of rare earth (Tb) with N-phenylanthranilic acid and 1,10-phenanthroline were synthesized and their compositions were characterized by elemental analysis. The compositions of the complexes have been confirmed to be TbL3. 4H2O and TbL3 phen.2H20 (L: N-phenylanthranilic acid, phen: 1;10-phenanthroline). The spectroscopic properties of the complexes were discussed. The result shows that the luminescence intensities of binary and ternary complexes were decreased by N-phenylanthranilic acid and 1,10-phenanthroline. It is indicated that the intensity of Tb depends on the structure of ligands. The structure, energy transfer and energy matching were studied, and it is concluded that the structure of complex affects the luminescence properties of the complexes.


Assuntos
Fenamatos/química , Fluorescência , Compostos Organometálicos/química , Fenantrolinas/química , Térbio/química , Compostos Organometálicos/síntese química , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Análise Espectral Raman
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(7): 799-802, 2004 Jul.
Artigo em Zh | MEDLINE | ID: mdl-15766074

RESUMO

The complexes of europium(II) with camphoric acid and 1,10-phenanthroline have been synthesized and characterized by elemental analysis, (1)H NMR, IR and FT-Raman. The compositions of the complexes have been confirmed to be Eu2 (CA)3.(2)H2O and Eu2 (CA)3 (phen)2 (CA: camphoric acid, phen: 1, 10-phenanthroline). In addition, the camphoric acid and 1, 10-phenanthrolinemixed coordination compounds of Eu3+ -La3+ have been synthesized. Three-dimensional fluorescence spectra showed that the optimum excitation wavelength was 310 nm, and the strongest emission wavelength was 612 nm. When 310 nm light was used as an excitation wavelength, the seven bands due to (5)D0 - (7) F0 (579 nm), (5)D0 - (7)F1 (594 nm), (5)D0 - (7)F2 (612 and 620 nm), (5)D0 - (7)F3 (650 nm) and (5)D0 - (7)F4 (689 and 697 nm) were observed between 550-700 nm, in which (5)D0 - (7)F2 transitions contain two lines (612 and 620 nm), and (5)D0 - (7)F4 transitions also contain two lines (689 and 697 nm). The excitation spectra showed that excitation band was from 240 to 340 nm, and the maximum was at about 310 nm. The fluorescence studies on all of samples showed that the fluorescence intensities of europium ions were sensitized by lanthanum ions, but the peak position of their emission band did not shift obviously.


Assuntos
Cânfora/química , Európio/química , Luz , Fenantrolinas/química , Espectrometria de Fluorescência/métodos , Cânfora/análogos & derivados , Fotoquímica
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(6): 708-12, 2004 Jun.
Artigo em Zh | MEDLINE | ID: mdl-15766189

RESUMO

In this paper, ternary solid complexes of Tb-benzioc acid-1,10-phenanthroline have been synthesized. Compared with binary complexes of Tb-benzioc acid, their properties were investigated. The results showed that the second ligand-phenanthroline enhanced the fluorescence intensities of Tb3+, and shortened its fluorescence lifetime, and it was found that the aggregative state influenced the luminescence properties of ternary complexes. When particulates dispersed to a certain degree, the probability of 5D4-->7F5 transition of Tb3+ was great, so, green fluorescence was observed for the complexes. With the aggregation of particles, the probability of 5D4-->7F5 transition of Tb3+ decreased, while the probability of D4-->7F3 transition increased. Therefore, ternary complexes of Tb-benzoic acid-1,10-phenanthroline exhibited yellow fluorescence. In addition, spectroscopic properties of the complexes were investigated.


Assuntos
Benzoatos/química , Fluorescência , Luz , Fenantrolinas/química , Espectrometria de Fluorescência/métodos , Luminescência , Teste de Materiais , Transição de Fase , Fotoquímica/métodos , Análise Espectral
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 22(6): 935-7, 2002 Dec.
Artigo em Zh | MEDLINE | ID: mdl-12914168

RESUMO

The bonding-type rare earth polymers-polypropenic-acid terbium film was prepared through the bonding way. Three-dimension fluorescence spectra showed that the optimum excitation wavelength was 306 nm, the strongest emission wavelength was 544 nm. The terbium polypropenic-acid film showed the characteristic Tb3+ emission when excited at 306 nm due to 5D4-7FJ transition (J = 6, 5, 4 and 3). The emission maximum at 544 nm was ascribed to 5D4-7F5 transition of Tb3+ and presented strong green emission. The luminescent properties of Tb3+ were not affected by polymerism of propenic-acid and the transparency of polypropenic-acid in visible light region was not affected by the dopping Tb3+. The fluorescence properties and spectroscopic properties of the terbium polypropenic-acid were investigated by excitation spectrum, emission spectrum, IR, far-IR, and Raman spectrum.


Assuntos
Polipropilenos/química , Térbio/química , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
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