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1.
High-fat diet, microbiome-gut-brain axis signaling, and anxiety-like behavior in male rats
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Noronha, Sylvana I. S. Rendeiro de
; Moraes, Lauro Angelo Gonçalves de
; Hassell Jr., James E.
; Stamper, Christopher E.
; Arnold, Mathew R.
; Heinze, Jared D.
; Foxx, Christine L.
; Lieb, Margaret M.
; Cler, Kristin E.
; Karns, Bree L.
; Jaekel, Sophia
; Loupy, Kelsey M.
; Silva, Fernanda C. S.
; Chianca-Jr., Deoclécio Alves
; Lowry, Christopher A.
; Menezes, Rodrigo Cunha de
.
Abstract Obesity, associated with the intake of a high-fat diet (HFD), and anxiety are common among those living in modern urban societies. Recent studies suggest a role of microbiome-gut-brain axis signaling, including a role for brain serotonergic systems in the relationship between HFD and anxiety. Evidence suggests the gut microbiome and the serotonergic brain system together may play an important role in this response. Here we conducted a nine-week HFD protocol in male rats, followed by an analysis of the gut microbiome diversity and community composition, brainstem serotonergic gene expression (tph2, htr1a, and slc6a4), and anxiety-related defensive behavioral responses. We show that HFD intake decreased alpha diversity and altered the community composition of the gut microbiome in association with obesity, increased brainstem tph2, htr1a and slc6a4 mRNA expression, including in the caudal part of the dorsomedial dorsal raphe nucleus (cDRD), a subregion previously associated with stress- and anxiety-related behavioral responses, and, finally, increased anxiety-related defensive behavioral responses. The HFD increased the Firmicutes/Bacteroidetes ratio relative to control diet, as well as higher relative abundances of Blautia, and decreases in Prevotella. We found that tph2, htr1a and slc6a4 mRNA expression were increased in subregions of the dorsal raphe nucleus in the HFD, relative to control diet. Specific bacterial taxa were associated with increased serotonergic gene expression in the cDRD. Thus, we propose that HFD-induced obesity is associated with altered microbiome-gut-serotonergic brain axis signaling, leading to increased anxiety-related defensive behavioral responses in rats.
2.
Characterization of Flavonoids Profiles in Polar Extracts from Croton grewioides Baill. Using Ultra-High Resolution Mass Spectrometry Baill UltraHigh Ultra High
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Nascimento, Pedro E. S. do
; Prado, Vilma M. J.
; Jesus, Raphael A. de
; Silva, Wenes R. da
; Wisniewski Jr., Alberto
; Sá Filho, José C. F.
; Blank, Arie F.
; Souza, Daniel A. de
; Wartha, Elma R. S. A.
; Nogueira, Paulo C. L.
; Moraes, Valéria R. S.
.
Journal of the Brazilian Chemical Society
- Métricas do periódico
Research to identify plant bioactive compounds led to the evolution of extraction methods. This study optimized ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) to extract the flavonoids of Croton grewioides Baill. species contributing to characterize the polar extract profile and understand the antioxidant potential of these plant constituents. The use of experimental design and statistical treatments enabled the determination of the ideal conditions for each technique. The extracts of five accessions of C. grewioides were obtained under the optimized extraction conditions and were analyzed using ultra high-resolution mass spectrometry (FT-Orbitrap MS) operating at negative ionization mode for flavonoids detection. The accurate experimental mass obtained to the main compounds was used to attribute the molecular formula. Chemical structures of the main compounds detected were proposed using structure data bases. Chemometric analysis were performed with two FT-Orbitrap MS spectra samples using the identified metabolites and, the antioxidant activity data, showing that for this species the MAE was most effective in extracting the antioxidant compounds. It was possible to propose the structures for forty compounds in the C. grewioides extracts, demonstrating the excellent performance of the FT-Orbitrap MS in providing information on the chemical profile of polar compounds in plant extracts. methods ultrasoundassisted ultrasound assisted UAE (UAE microwaveassisted microwave (MAE Baill constituents technique C highresolution high resolution FTOrbitrap FT Orbitrap detection formula bases
3.
Silver Tungstate Obtained via Successive Seed Crystal Growth: Structural, Morphological, Optical, and Photocatalytic Properties Growth Structural Morphological Optical
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Santos, Germano P.
; Silva, Francisco C. M.
; Cruz-Filho, João F.
; Luz, Roberto A. S.
; Luz Jr., Geraldo E.
.
Journal of the Brazilian Chemical Society
- Métricas do periódico
Synthesis routes and parameters such as synthesis time, precursor molar ratio, pH, and temperature are critical for generating oxides of various sizes and morphological aspects. However, there is no information on how to prepare silver tungstate (Ag2WO4) crystals of different shapes and sizes under laboratory conditions and without using sulfating agents. In this study, we attempted to fill this gap by preparing α-Ag2WO4 crystals of various sizes and morphologies using the coprecipitation method in a 3 h interval at room temperature and without using sulfating agents. The powder X-ray diffraction analysis confirmed that all crystals had an orthorhombic structure, whereas Fourier-transform infrared spectroscopy revealed the degree of structural disorder in the bonds between the atoms in the materials. Scanning electron microscopy revealed that the α-Ag2WO4 crystals had different sizes (5.37-26.83 µm) and morphologies (tetragonal prism, rod, and cypress leave-like rod), whereas ultraviolet-visible diffuse reflectance spectroscopy analysis indicated the optical band gap energy (2.92-3.05 eV), calculated using the method proposed by Kubelka and Munk. Catalytic tests revealed that the synthesized samples with the smallest crystals (AW1) and a tetragonal prism morphology degraded dye more efficiently (apparent rate constant (k) = 5.86 × 10-3 min-1) than other samples. time ratio pH aspects However Ag2WO4 AgWO Ag WO (Ag2WO4 agents study αAg2WO4 αAgWO α α-Ag2WO Xray X ray structure Fouriertransform Fourier transform materials 5.3726.83 5372683 5.37 26.83 5 37 26 83 (5.37-26.8 µm rod leavelike leave like , rod) ultravioletvisible ultraviolet visible 2.923.05 292305 2.92 3.05 2 92 05 (2.92-3.0 eV, eV eV) Munk AW1 AW (AW1 apparent k (k 586 86 5.8 103 10 10- min1 min 1 min-1 Ag2WO (Ag2WO αAg αAg2WO 3726 5.3726.8 537268 537 5.3 2683 26.8 8 (5.37-26. 923 2.923.0 29230 292 2.9 305 3.0 9 0 (2.92-3. (AW 58 5. min- 372 5.3726. 53726 53 268 26. (5.37-26 2.923. 2923 29 2. 30 3. (2.92-3 5.3726 5372 (5.37-2 2.923 (2.92- 5.372 (5.37- (2.92 (5.37 (2.9 (5.3 (2. (5. (2 (5 (
4.
Non-Ionizing Radiation Analysis in Close Proximity to Antenna Tower: A Case Study in Northeast Brazil
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Diniz, Andre B. de F.
; Sousa Jr., Vicente A. de
; Rodrigues, Marcio E. C.
; Mendonça, Halysson B.
; Silva, Gutembergue Soares da
; Pinheiro, Fred Sizenando Rossiter
.
Journal of Microwaves, Optoelectronics and Electromagnetic Applications
- Métricas do periódico
Abstract While the amount of telecommunications services grows rapidly in the whole world, humans get potentially more exposed to Non-Ionizing Radiation (NIR) from a number of different sources. Measurements of NIR levels are relevant in order to compare the results with national and international standards, aiming at the preservation of human health. Thus, it is of great interest to explore a variety of topics regarding this subject. Based on this need, this paper has a number of goals, including monitoring radiation levels in an everyday situation, an investigation of how national and international regulations organs address NIR levels and a demonstration of scientific production trends regarding this topic. The work also presents a bibliometric study about the main scientific productions and trends related to NIR measurements, with focus on the field of Telecommunications. The analysis is based on the databases of Web of Science (WOS) and Scopus, computing publications in the last 10 and 3 years, showing a trend evaluation. Among the main results from this exploratory investigation, there is an exponential growth in the number of publications about NIR, ranging from research in physics to medicine. The way research contribution in different countries is also shown, in order to support the relevance of the topic in defining new tendencies for new investigations. Furthermore, the NIR exposure limits and measurement criteria are presented both in Brazilian and in international norms, demonstrating how different national regulations can be when compared to international guidelines. Another contribution is a case study in Natal, Brazil, where NIR levels were monitored in four distinct locations over a period of 24 hours each and compared to the current regulations. The result is a quantitative analysis of the amount of radiation that some populations might be exposed to in distinct moments of the day. Measurements were carried out in the proximity of an antenna spot, since it could represent a source of high NIR levels (a worst case of human exposure). This campaign differs from older studies by including a more intense usage of microwaves frequencies due to operating 4G and pre-5G systems in Brazil. Finally, a statistical study involving the measurements is conducted, concluding the analysis of how some population groups might be affected by NIR.
https://doi.org/10.1590/2179-10742021v20i1833
361 downloads
5.
Multifunctionality of βCD/Ofloxacin and HPβCD/Ofloxacin Complexes: Improvement of the Antimicrobial Activity and Apoptosis Induction on Lung Adenocarcinoma A549 Cells
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Amaro, Bolivar R.
; Alves, Caio C. S.
; Ferreira, Gabriella F.
; Carvalho, Paloma E.
; Silva, Jeferson G. da
; Souza, Cleonice A.
; Cardoso Jr., Oswaldo
; Carli, Alessandra P.
; Machado, Fabiana S.
; Denadai, Ângelo M. L.
; Castro, Sandra B. R.
.
Journal of the Brazilian Chemical Society
- Métricas do periódico
The ofloxacin (OFLOX) is a second-generation synthetic antibiotic that can be classified as a multifunctional drug, but is a poorly soluble drug, which influences its efficiency. The inclusion complexes of OFLOX with β-cyclodextrin (βCD) or hydroxypropyl-β-cyclodextrin (HPβCD) can improve the chemical characteristics of the drug; however, studies showing the biological activity of these inclusion complexes are still scarce. The present work aimed to investigate the multifunctionality of the OFLOX and their inclusion complexes. Thus, the 1:1 βCD/OFLOX or HPβCD/OFLOX were prepared and analyzed by Fourier transform infrared spectroscopy (FTIR), thermogravimetric and differential thermal analysis (TGA and DTA), 1H nuclear magnetic resonance (NMR) and isothermal titration calorimetry (ITC). The antitumor and antibacterial effects were assessed. The results confirm the formation of the inclusion complexes, which had lower minimum inhibitory concentration (MIC) values, higher cytotoxicity and promoted the apoptosis. The present study showed, for the first time, the promising effects of the inclusion complexes as antitumor, improving the biological activities of the uncomplexed ofloxacin.
https://doi.org/10.21577/0103-5053.20200145
259 downloads
6.
Fire resistance of ceramic-masonry sealing blocks using intumescent paint protection
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Sales, C. A. S.
; Nascimento, C. F. G.
; Silva, T. M.
; Barreto, L. M.
; Lordsleem Jr., P. C.
; Soares, W. A.
; Castro-Borges, P.
; Monteiro, E. C. B.
.
RESUMO Avaliou-se a eficiência da proteção superficial de estruturas de alvenaria de vedação com tinta intumescente em relação à resistência mecânica e ao isolamento térmico. Foram utilizados 60 blocos cerâmicos de alvenaria de vedação. A temperatura da face diretamente exposta à chama foi em média 25% inferior para o bloco com a proteção passiva. A resistência à compressão dos blocos com proteção passiva foi cerca de 70% superior aos blocos sem proteção, após 60 minutos de exposição direta a chama. Mais de 70% dos blocos sem proteção passiva e que foram expostos a chama tiveram resistência a compressão de 1,35 MPa, enquanto 100% dos blocos com proteção tiveram valores de 2,38 MPa, mesmo após 60 minutos de exposição.
ABSTRACT The efficiency of surface protection of sealing masonry structures with intumescent ink was evaluated in relation to mechanical resistance and thermal insulation. Sixty ceramic sealing masonry blocks were used. The temperature of the face directly exposed to the flame was on average 25% lower for the block with passive protection. The compressive strength of the blocks with passive protection was about 70% higher than the unprotected blocks, after 60 minutes of direct exposure to the flame. More than 70% of the blocks without passive protection and that were exposed to flame had compressive resistance of 1.35 MPa, while 100% of the blocks with protection had values 2.38 MPa, even after 60 minutes of exposure.
RESUMEN Se evaluó la eficiencia de la protección superficial de las estructuras de mampostería de sellado con tinta intumescente en relación con la resistencia mecánica y el aislamiento térmico. Se utilizaron sesenta bloques de mampostería de sellado cerámico. La temperatura de la cara directamente expuesta a la llama fue en promedio un 25% menor para el bloque con protección pasiva. La fuerza de compresión de los bloques con protección pasiva fue aproximadamente 70% mayor que la de los bloques sin protección, después de 60 minutos de exposición directa a la llama. Más del 70% de los bloques sin protección pasiva y expuestos a llamas tenían una resistencia a la compresión de 1,35 MPa, mientras que el 100% de los bloques con protección tenían valores de 2,38 MPa, incluso después de 60 minutos de exposición.
https://doi.org/10.21041/ra.v10i1.417
10 downloads
7.
APCI(+)FT-ICR MS Analysis of Hydrocarbons Using Isooctane as Ionizing Reagent - A Comparison with HTGC-FID, GC×GC-MS and NMR
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Tose, Lilian V.
; Silva, Samantha R. C.
; Barros, Eliane V.
; Souza, Lindamara M.
; Pinto, Fernanda E.
; Palomino, Debora K.
; Freitas, Jair C. C.
; Thompson, Christopher J.
; Vaz, Boniek G.
; Lacerda Jr., Valdemar
; Romão, Wanderson
.
Journal of the Brazilian Chemical Society
- Métricas do periódico
Hydrocarbons present in saturated fractions of crude oils can be assessed by atmospheric pressure chemical ionization (APCI) using small hydrocarbons as ionizing reagents in a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS). In this work, five paraffin standards of different average molar mass distributions (Mw) were easily ionized by APCI(+)FT-ICR MS using isooctane as the reagent gas. Data of Mw, carbon number and double bond equivalent (DBE) distributions corresponding to linear and cyclic hydrocarbons (HCs) were compared to results obtained from analysis of high temperature gas chromatography with a flame ionization detector (HTGC-FID), comprehensive two-dimensional gas chromatography coupled to mass spectrometry (GC×GC-MS) and 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. APCI(+)FT-ICR MS data showed good agreement with those of analytical techniques. Furthermore, the ability of APCI(+) to assess n-paraffin, even in blends with polyaromatic hydrocarbon molecules such as coronene (Mw = 301 Da) at concentrations from 2.5 to 25 µg mL-1, was demonstrated. The typical MS paraffin profile (containing repeating mass units of 14 Da) was clearly confirmed, being totally suppressed when a concentration of 25 µg mL-1 of coronene was used. This phenomenon was also evidenced in one of two saturated fractions produced using saturates, aromatics and polar (SAP) compound fractionation methodology.
https://doi.org/10.21577/0103-5053.20180249
1049 downloads
8.
Passive vibration control using a metaconcrete thin plate
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Abstract We investigated the band structure of flexural waves propagating in a metaconcrete thin plate, consisting of a concrete matrix reinforced by steel inclusions coated by rubber in square and triangular lattices. We considered the classical Kirchhoff-Love thin plate theory. We also studied the influence of inclusion geometry - circular, square and rotated square with a 45° angle of rotation with respect to the x, y axes. Improved plane wave expansion method was used to solve the wave equation considering flexural wave propagation in the xy plane. Flat bands and locally resonant band gaps were observed for all types of inclusion studied regarding square and triangular lattices. The locally resonant band gaps for square and rotated square inclusions in a triangular lattice were slightly shifted to higher frequencies than that given by circular inclusion. We suggest that the metaconcrete thin plate studied should be feasible for flexural vibration control in low frequencies.
https://doi.org/10.1590/0366-6913201965s12597
735 downloads
9.
The use of tire rubber in the production of high-performance concrete
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Silva, F. M.
; Miranda Jr., E. J. P.
; Santos, J. M. C. Dos
; Gachet-Barbosa, L. A.
; Gomes, A. E.
; Lintz, R. C. C.
.
Abstract The advances in concrete technology lead to the search for alternative materials that provide improvements in concrete properties while at the same time collaborating with sustainable practices in construction. In this study, the influence of the incorporation of waste tire rubber on the mechanical properties of high-performance concrete was discussed. The waste rubber from the tire retreading process was used in partial substitution of the fine aggregate (sand) in the percentages of 7.5%, 15% and 30% with respect to the mass of the sand. For the characterization of the concrete, the following tests were carried out: water absorption, void index, specific density, compressive strength, flexural tensile strength, modulus of elasticity and microscopy analysis. The incorporation of rubber as aggregate in high-performance concrete proved to be promising for the production of a structural concrete with special characteristics, besides collaborating with the proper disposal of waste tires.
https://doi.org/10.1590/0366-6913201965s12598
1841 downloads
10.
Chain Elongation Influence in Copolymerization with Different Diesters of Norbornene 2,3-Dicarboxylic Acid Monomers via ROMP under Air Atmosphere
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Braga, Sâmia D.
; Vieira, Vanessa B.
; Silva-Neta, Cristina V.
; Batista, Nouga C.
; Fonseca, Larissa R.
; Lima-Neto, Benedito S.
; Luz Jr., Geraldo E.
; Sá, José Luiz S.
.
Journal of the Brazilian Chemical Society
- Métricas do periódico
Diesters of norbornene 2,3-dicarboxylic acid (NBE-(COOR)2), in which R is an alkyl group, were synthesized from one-pot synthesis method with 5-norbornene-2,3-dicarboxylic acid and methanol and ethanol. The new monomers were, respectively, the dimethyl ester NBE-(COOCH3)2 and diethyl ester NBE-(COOCH2CH3)2. Norbornene was mixed with these monomers at different proportions and copolymerized via ring-opening metathesis polymerization (ROMP) with 1st generation Grubbs' catalyst. All experiments were conducted under air atmosphere to obtain the isolated polymer. Yield results show that elongation of the R group influenced the copolymerization process. At the same co-monomer proportion, the yield decreases as a function of the R group elongation. Thermogravimetric analysis (TGA) was performed and, in all cases, more than one thermal degradation process was observed. The first process was assigned to pendent group degradation, whereas the second process was assigned to main chain degradation. These thermal processes were also influenced by different elongation of the aliphatic group of the pendent chain.
https://doi.org/10.21577/0103-5053.20170233
665 downloads
11.
Brazilian legislation on genetic heritage harms Biodiversity Convention goals and threatens basic biology research and education
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ALVES, RUY JOSÉ V.
; WEKSLER, MARCELO
; OLIVEIRA, JOÃO A.
; BUCKUP, PAULO A.
; POMBAL JR., JOSÉ P.
; SANTANA, HÉLCIO R.G.
; PERACCHI, ADRIANO LÚCIO
; KELLNER, ALEXANDER W.A.
; ALEIXO, ALEXANDRE
; LANGGUTH, ALFREDO
; ALMEIDA, ALZIRA MARIA P. DE
; ALBERNAZ, ANA LUISA
; RIBAS, CAMILA C.
; ZILBERBERG, CARLA
; GRELLE, CARLOS EDUARDO V.
; ROCHA, CARLOS F.D.
; LAMAS, CARLOS JOSÉ E.
; HADDAD, CÉLIO F.B.
; BONVICINO, CIBELE R.
; PRADO, CYNTHIA P.A.
; LIMA, DANIELA O. DE
; ROSSA-FERES, DENISE C.
; SANTOS, FABRÍCIO R. DOS
; SALIMENA, FÁTIMA REGINA G.
; PERINI, FERNANDO A.
; BOCKMANN, FLÁVIO A.
; FRANCO, FRANCISCO LUÍS
; GIUDICE, GISELE M.L. DEL
; COLLI, GUARINO R.
; VIEIRA, IMA CÉLIA G.
; MARINHO-FILHO, JADER
; WERNECK, JANE M.C.F.
; SANTOS, JORGE A.D. DOS
; NASCIMENTO, JORGE LUIZ DO
; NESSIMIAN, JORGE LUIZ
; CORDEIRO, JOSÉ LUIS P.
; CLARO, KLEBER DEL
; SALLES, LEANDRO O.
; CASATTI, LILIAN
; PY-DANIEL, LUCIA HELENA R.
; SILVEIRA, LUÍS FÁBIO
; TOLEDO, LUÍS FELIPE
; OLIVEIRA, LUIZ F. DE
; MALABARBA, LUIZ ROBERTO
; SILVA, MARCELO D. DA
; COURI, MÁRCIA S.
; MARTINS, MÁRCIO
; TAVARES, MARCOS D.S.
; SOBRAL, MARCOS EDUARDO G.
; VIEIRA, MARCUS VINÍCIUS
; OLIVEIRA, MARIA DE LOURDES A.
; PINNA, MÁRIO DE
; HOPKINS, MICHAEL J.G.
; SOLÉ, MIRCO
; MENEZES, NAÉRCIO A.
; PASSOS, PAULO
; D’ANDREA, PAULO SERGIO
; PINTO, PEDRO C.E.A.
; VIANA, PEDRO L.
; TOLEDO, PETER M.
; REIS, ROBERTO E.
; VILELA, ROBERTO
; BASTOS, ROGÉRIO P.
; COLLEVATTI, ROSANE G.
; CERQUEIRA, RUI
; CASTROVIEJO-FISHER, SANTIAGO
; CARAMASCHI, ULISSES
.
Anais da Academia Brasileira de Ciências
- Métricas do periódico
https://doi.org/10.1590/0001-3765201820180460
7311 downloads
12.
Dosimetria externa em minas de caulim na região do Seridó do Nordeste do Brasil
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Spacov, I. C. G.
; Silva, A. N. C. da
; Amaral, R. dos S.
; Santos Jr., J. A. dos
; Bezerra, J. D.
; Araújo, E. E. N. de
; Costa, M. C. A.
.
Resumo A atividade mineradora pode apresentar potenciais riscos radiológicos em decorrência da presença de radionuclídeos primordiais associados aos minérios explorados. No nordeste brasileiro, as mineradoras de caulim estão estabelecidas principalmente na região da Província Pegmatítica Borborema-Seridó localizada entre os estados da Paraíba e do Rio Grande do Norte. O minério da caulinita traz agregado materiais formados por elementos das séries do U-238 e Th-232, além do K-40. A presença desses radioisótopos naturais pode conferir elevados níveis de radiação ionizante associados ao material extraído das minas. A UNSCEAR divulga a dose efetiva média mundial de exposição às fontes naturais de radiação como 2,42 mSv.a-1. Estudos nacionais e internacionais demonstraram que a atividade radioativa do caulim pode exceder os valores médios mundiais. Este estudo objetivou o mapeamento radiométrico das áreas de exploração do caulim na região do Seridó devido à proximidade com jazidas de urânio. Foi utilizado um detector cintilador de NaI (Tl) para realizar as medições de taxa de dose efetiva nas proximidades de quatro minas da região e foram obtidos valores que variaram entre 1,37 a 2,94 mSv.a-1. Os resultados obtidos sugerem a necessidade de uma abordagem mais profunda como a obtenção de amostras de solo e rocha para outras análises.
Abstract The mining activity may have potential radiological hazards due to the presence of primordial radionuclides associated with the exploited ore. In northeastern of Brazil, kaolin mining companies are mainly located in the region of Borborema-Seridó Pegmatitic Province located between the states of Paraíba and Rio Grande do Norte. The kaolinite ore brings aggregate materials formed by elements belonging to the series of U-238 and Th-232, beyond K-40. The presence of these natural radioisotopes can confer high levels of ionizing radiation associated with the material extracted from the mines. The UNSCEAR reports the global average effective dose of exposure to natural sources radiation as 2.42 mSv.y-1. National and international studies have shown that the activity of kaolin may exceed the global averages. This study aimed the radiometric mapping of kaolin exploration areas in the Seridó region due to its proximity to uranium deposits. A scintillator detector of NaI (Tl) was used to perform effective dose rate measurements in the vicinity of four mines in the region, and values that ranged from 1.37 to 2.94 mSv.y-1 were obtained. The results suggest a need for a deeper approach such as obtaining soil and rock samples for more analyzes.
https://doi.org/10.1590/0366-69132018643692201
1570 downloads
13.
Update of the Brazilian floristic list of Algae and Cyanobacteria
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Menezes, Mariângela
; Bicudo, Carlos E. M.
; Moura, Carlos W. N.
; Alves, Aigara M.
; Santos, Alana A.
; Pedrini, Alexandre de G.
; Araújo, Andréa
; Tucci, Andrea
; Fajar, Aurelio
; Malone, Camila
; Kano, Cecília H.
; Sant'Anna, Célia L.
; Branco, Ciro Z.
; Odebrecht, Clarisse
; Peres, Cleto K.
; Neuhaus, Emanuel B.
; Eskinazi-Leça, Enide
; Aquino, Eveline
; Nauer, Fabio
; Santos, Gabriel N.
; Amado Filho, Gilberto M.
; Lyra, Goia M.
; Borges, Gyslaine C.P.
; Costa, Iara O.
; Nogueira, Ina de S.
; Oliveira, Ivania B.
; Paula, Joel. C.de
; Nunes, José M. de C.
; Lima, Jucicleide C.
; Santos, Kleber R.S.
; Ferreira, Leandro C.
; Gestinari, Lísia M.S.
; Cardoso, Luciana S.
; Figueiredo, Marcia A.O.
; Silva, Marcos H.
; Barreto, Maria B.B.B.
; Henriques, Maria C.O.
; Cunha, Maria da G.G.S.
; Bandeira-Pedrosa, Maria E.
; Oliveira-Carvalho, Maria F.
; Széchy, Maria T.M.
; Azevedo, Maria T.P.
; Oliveira, Mariana C. de
; Cabezudo, Mariê M.
; Santiago, Marilene F.
; Bergesh, Marli
; Fujii, Mutuê T.
; Bueno, Norma C.
; Necchi Jr., Orlando
; Jesus, Priscila B.
; Bahia, Ricardo G.
; Khader, Samir
; Alves-da-Silva, Sandra M.
; Guimarães, Silvia M.P.B.
; Pereira, Sonia M.B.
; Caires, Taiara A.
; Meurer, Thamis
; Cassano, Valéria
; Werner, Vera R.
; Gama Jr., Watson A. da
; Silva, Weliton J. da
.
Resumo Apresenta-se uma síntese atualizada de informações sobre algas no Brasil objetivando refinar os dados reunidos até o presente, bem como avaliar os avanços sobre o conhecimento da diversidade de algas no país desde a publicação do Catálogo de Plantas e Fungos do Brasil. Os resultados de 2015 mostraram um acréscimo de 1.250 espécies (35.7%) a um total de 4.747 em relação a 2010. As classes mais diversas em número de espécies foram Bacillariophyceae, Conjugatophyceae, Florideophyceae, Cyanophyceae, Dinophyceae e Euglenophyceae. Bacillariophyceae e Cyanophyceae tiveram o maior acréscimo de espécies no intervalo de cinco anos. A região Sudeste e Sul foram as mais diversas, porém, as regiões Nordeste com os estados do Piauí e Sergipe e Centro-Oeste com os estados de Mato Grosso, Goiás e Distrito Federal destacaram-se no cenário da biodiversidade nacional. Apesar da escassez de taxonomistas e da infraestrutura limitada, os resultados obtidos evidenciaram um avanço significativo no conhecimento da diversidade de algas no país nesse período de cinco anos, iniciando uma mudança quanto as diferenças geográficas regionais.
Abstract An updated synthesis of cyanobacteria and algae information is presented for Brazil aiming to refine the data gathered to date and evaluate the progress of the biodiversity knowledge about these organisms in the country since the publication of the Catálogo de Plantas e Fungos do Brasil. The results of 2015 showed an increase of 1,250 species (35.7%) when compared to 2010, reaching a total of 4,747 species. The most diverse classes in species number were the Bacillariophyceae, Conjugatophyceae, Florideophyceae, Cyanophyceae, Dinophyceae and Euglenophyceae. Bacillariophyceae and Cyanophyceae had the highest increase in species number in the five-year interval. The Southeast and South regions were the most diverse, however, the Northeast, with the states of Piauí and Sergipe, and the Central-west region, with Mato Grosso, Goiás and Distrito Federal, also stood out in the national algal biodiversity scenario. Despite the shortage of taxonomists and limited infrastructure, the results showed a significant improvement in the knowledge regarding the diversity of cyanobacteria and algae in the country during the study period, starting to even out regional geographical differences caused by subsampling.
https://doi.org/10.1590/2175-7860201566408
4865 downloads
14.
Growing knowledge: an overview of Seed Plant diversity in Brazil
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Zappi, Daniela C.
; Filardi, Fabiana L. Ranzato
; Leitman, Paula
; Souza, Vinícius C.
; Walter, Bruno M.T.
; Pirani, José R.
; Morim, Marli P.
; Queiroz, Luciano P.
; Cavalcanti, Taciana B.
; Mansano, Vidal F.
; Forzza, Rafaela C.
; Abreu, Maria C.
; Acevedo-Rodríguez, Pedro
; Agra, Maria F.
; Almeida Jr., Eduardo B.
; Almeida, Gracineide S.S.
; Almeida, Rafael F.
; Alves, Flávio M.
; Alves, Marccus
; Alves-Araujo, Anderson
; Amaral, Maria C.E.
; Amorim, André M.
; Amorim, Bruno
; Andrade, Ivanilza M.
; Andreata, Regina H.P.
; Andrino, Caroline O.
; Anunciação, Elisete A.
; Aona, Lidyanne Y.S.
; Aranguren, Yani
; Aranha Filho, João L.M.
; Araújo, Andrea O.
; Araújo, Ariclenes A.M.
; Araújo, Diogo
; Arbo, María M.
; Assis, Leandro
; Assis, Marta C.
; Assunção, Vivian A.
; Athiê-Souza, Sarah M.
; Azevedo, Cecilia O.
; Baitello, João B.
; Barberena, Felipe F.V.A.
; Barbosa, Maria R.V.
; Barros, Fábio
; Barros, Lucas A.V.
; Barros, Michel J.F.
; Baumgratz, José F.A.
; Bernacci, Luis C.
; Berry, Paul E.
; Bigio, Narcísio C.
; Biral, Leonardo
; Bittrich, Volker
; Borges, Rafael A.X.
; Bortoluzzi, Roseli L.C.
; Bove, Cláudia P.
; Bovini, Massimo G.
; Braga, João M.A.
; Braz, Denise M.
; Bringel Jr., João B.A.
; Bruniera, Carla P.
; Buturi, Camila V.
; Cabral, Elza
; Cabral, Fernanda N.
; Caddah, Mayara K.
; Caires, Claudenir S.
; Calazans, Luana S.B.
; Calió, Maria F.
; Camargo, Rodrigo A.
; Campbell, Lisa
; Canto-Dorow, Thais S.
; Carauta, Jorge P.P.
; Cardiel, José M.
; Cardoso, Domingos B.O.S.
; Cardoso, Leandro J.T.
; Carneiro, Camila R.
; Carneiro, Cláudia E.
; Carneiro-Torres, Daniela S.
; Carrijo, Tatiana T.
; Caruzo, Maria B.R.
; Carvalho, Maria L.S.
; Carvalho-Silva, Micheline
; Castello, Ana C.D.
; Cavalheiro, Larissa
; Cervi, Armando C.
; Chacon, Roberta G.
; Chautems, Alain
; Chiavegatto, Berenice
; Chukr, Nádia S.
; Coelho, Alexa A.O.P.
; Coelho, Marcus A.N.
; Coelho, Rubens L.G.
; Cordeiro, Inês
; Cordula, Elizabeth
; Cornejo, Xavier
; Côrtes, Ana L.A.
; Costa, Andrea F.
; Costa, Fabiane N.
; Costa, Jorge A.S.
; Costa, Leila C.
; Costa-e-Silva, Maria B.
; Costa-Lima, James L.
; Cota, Maria R.C.
; Couto, Ricardo S.
; Daly, Douglas C.
; De Stefano, Rodrigo D.
; De Toni, Karen
; Dematteis, Massimiliano
; Dettke, Greta A.
; Di Maio, Fernando R.
; Dórea, Marcos C.
; Duarte, Marília C.
; Dutilh, Julie H.A.
; Dutra, Valquíria F.
; Echternacht, Lívia
; Eggers, Lilian
; Esteves, Gerleni
; Ezcurra, Cecilia
; Falcão Junior, Marcus J.A.
; Feres, Fabíola
; Fernandes, José M.
; Ferreira, D.M.C.
; Ferreira, Fabrício M.
; Ferreira, Gabriel E.
; Ferreira, Priscila P.A.
; Ferreira, Silvana C.
; Ferrucci, Maria S.
; Fiaschi, Pedro
; Filgueiras, Tarciso S.
; Firens, Marcela
; Flores, Andreia S.
; Forero, Enrique
; Forster, Wellington
; Fortuna-Perez, Ana P.
; Fortunato, Reneé H.
; Fraga, Cléudio N.
; França, Flávio
; Francener, Augusto
; Freitas, Joelcio
; Freitas, Maria F.
; Fritsch, Peter W.
; Furtado, Samyra G.
; Gaglioti, André L.
; Garcia, Flávia C.P.
; Germano Filho, Pedro
; Giacomin, Leandro
; Gil, André S.B.
; Giulietti, Ana M.
; A.P.Godoy, Silvana
; Goldenberg, Renato
; Gomes da Costa, Géssica A.
; Gomes, Mário
; Gomes-Klein, Vera L.
; Gonçalves, Eduardo Gomes
; Graham, Shirley
; Groppo, Milton
; Guedes, Juliana S.
; Guimarães, Leonardo R.S.
; Guimarães, Paulo J.F.
; Guimarães, Elsie F.
; Gutierrez, Raul
; Harley, Raymond
; Hassemer, Gustavo
; Hattori, Eric K.O.
; Hefler, Sonia M.
; Heiden, Gustavo
; Henderson, Andrew
; Hensold, Nancy
; Hiepko, Paul
; Holanda, Ana S.S.
; Iganci, João R.V.
; Imig, Daniela C.
; Indriunas, Alexandre
; Jacques, Eliane L.
; Jardim, Jomar G.
; Kamer, Hiltje M.
; Kameyama, Cíntia
; Kinoshita, Luiza S.
; Kirizawa, Mizué
; Klitgaard, Bente B.
; Koch, Ingrid
; Koschnitzke, Cristiana
; Krauss, Nathália P.
; Kriebel, Ricardo
; Kuntz, Juliana
; Larocca, João
; Leal, Eduardo S.
; Lewis, Gwilym P.
; Lima, Carla T.
; Lima, Haroldo C.
; Lima, Itamar B.
; Lima, Laíce F.G.
; Lima, Laura C.P.
; Lima, Leticia R.
; Lima, Luís F.P.
; Lima, Rita B.
; Lírio, Elton J.
; Liro, Renata M.
; Lleras, Eduardo
; Lobão, Adriana
; Loeuille, Benoit
; Lohmann, Lúcia G.
; Loiola, Maria I.B.
; Lombardi, Julio A.
; Longhi-Wagner, Hilda M.
; Lopes, Rosana C.
; Lorencini, Tiago S.
; Louzada, Rafael B.
; Lovo, Juliana
; Lozano, Eduardo D.
; Lucas, Eve
; Ludtke, Raquel
; Luz, Christian L.
; Maas, Paul
; Machado, Anderson F.P.
; Macias, Leila
; Maciel, Jefferson R.
; Magenta, Mara A.G.
; Mamede, Maria C.H.
; Manoel, Evelin A.
; Marchioretto, Maria S.
; Marques, Juliana S.
; Marquete, Nilda
; Marquete, Ronaldo
; Martinelli, Gustavo
; Martins da Silva, Regina C.V.
; Martins, Ângela B.
; Martins, Erika R.
; Martins, Márcio L.L.
; Martins, Milena V.
; Martins, Renata C.
; Matias, Ligia Q.
; Maya-L., Carlos A.
; Mayo, Simon
; Mazine, Fiorella
; Medeiros, Debora
; Medeiros, Erika S.
; Medeiros, Herison
; Medeiros, João D.
; Meireles, José E.
; Mello-Silva, Renato
; Melo, Aline
; Melo, André L.
; Melo, Efigênia
; Melo, José I.M.
; Menezes, Cristine G.
; Menini Neto, Luiz
; Mentz, Lilian A.
; Mezzonato, A.C.
; Michelangeli, Fabián A.
; Milward-de-Azevedo, Michaele A.
; Miotto, Silvia T.S.
; Miranda, Vitor F.O.
; Mondin, Cláudio A.
; Monge, Marcelo
; Monteiro, Daniele
; Monteiro, Raquel F.
; Moraes, Marta D.
; Moraes, Pedro L.R.
; Mori, Scott A.
; Mota, Aline C.
; Mota, Nara F.O.
; Moura, Tania M.
; Mulgura, Maria
; Nakajima, Jimi N.
; Nardy, Camila
; Nascimento Júnior, José E.
; Noblick, Larry
; Nunes, Teonildes S.
; O'Leary, Nataly
; Oliveira, Arline S.
; Oliveira, Caetano T.
; Oliveira, Juliana A.
; Oliveira, Luciana S.D.
; Oliveira, Maria L.A.A.
; Oliveira, Regina C.
; Oliveira, Renata S.
; Oliveira, Reyjane P.
; Paixão-Souza, Bruno
; Parra, Lara R.
; Pasini, Eduardo
; Pastore, José F.B.
; Pastore, Mayara
; Paula-Souza, Juliana
; Pederneiras, Leandro C.
; Peixoto, Ariane L.
; Pelissari, Gisela
; Pellegrini, Marco O.O.
; Pennington, Toby
; Perdiz, Ricardo O.
; Pereira, Anna C.M.
; Pereira, Maria S.
; Pereira, Rodrigo A.S.
; Pessoa, Clenia
; Pessoa, Edlley M.
; Pessoa, Maria C.R.
; Pinto, Luiz J.S.
; Pinto, Rafael B.
; Pontes, Tiago A.
; Prance, Ghillean T.
; Proença, Carolyn
; Profice, Sheila R.
; Pscheidt, Allan C.
; Queiroz, George A.
; Queiroz, Rubens T.
; Quinet, Alexandre
; Rainer, Heimo
; Ramos, Eliana
; Rando, Juliana G.
; Rapini, Alessandro
; Reginato, Marcelo
; Reis, Ilka P.
; Reis, Priscila A.
; Ribeiro, André R.O.
; Ribeiro, José E.L.S.
; Riina, Ricarda
; Ritter, Mara R.
; Rivadavia, Fernando
; Rocha, Antônio E.S.
; Rocha, Maria J.R.
; Rodrigues, Izabella M.C.
; Rodrigues, Karina F.
; Rodrigues, Rodrigo S.
; Rodrigues, Rodrigo S.
; Rodrigues, Vinícius T.
; Rodrigues, William
; Romaniuc Neto, Sérgio
; Romão, Gerson O.
; Romero, Rosana
; Roque, Nádia
; Rosa, Patrícia
; Rossi, Lúcia
; Sá, Cyl F.C.
; Saavedra, Mariana M.
; Saka, Mariana
; Sakuragui, Cássia M.
; Salas, Roberto M.
; Sales, Margareth F.
; Salimena, Fatima R.G.
; Sampaio, Daniela
; Sancho, Gisela
; Sano, Paulo T.
; Santos, Alessandra
; Santos, Élide P.
; Santos, Juliana S.
; Santos, Marianna R.
; Santos-Gonçalves, Ana P.
; Santos-Silva, Fernanda
; São-Mateus, Wallace
; Saraiva, Deisy P.
; Saridakis, Dennis P.
; Sartori, Ângela L.B.
; Scalon, Viviane R.
; Schneider, Ângelo
; Sebastiani, Renata
; Secco, Ricardo S.
; Senna, Luisa
; Senna-Valle, Luci
; Shirasuna, Regina T.
; Silva Filho, Pedro J.S.
; Silva, Anádria S.
; Silva, Christian
; Silva, Genilson A.R.
; Silva, Gisele O.
; Silva, Márcia C.R.
; Silva, Marcos J.
; Silva, Marcos J.
; Silva, Otávio L.M.
; Silva, Rafaela A.P.
; Silva, Saura R.
; Silva, Tania R.S.
; Silva-Gonçalves, Kelly C.
; Silva-Luz, Cíntia L.
; Simão-Bianchini, Rosângela
; Simões, André O.
; Simpson, Beryl
; Siniscalchi, Carolina M.
; Siqueira Filho, José A.
; Siqueira, Carlos E.
; Siqueira, Josafá C.
; Smith, Nathan P.
; Snak, Cristiane
; Soares Neto, Raimundo L.
; Soares, Kelen P.
; Soares, Marcos V.B.
; Soares, Maria L.
; Soares, Polyana N.
; Sobral, Marcos
; Sodré, Rodolfo C.
; Somner, Genise V.
; Sothers, Cynthia A.
; Sousa, Danilo J.L.
; Souza, Elnatan B.
; Souza, Élvia R.
; Souza, Marcelo
; Souza, Maria L.D.R.
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; Spina, Andréa P.
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; Stefano, Marina V.
; Stehmann, João R.
; Steinmann, Victor
; Takeuchi, Cátia
; Taylor, Charlotte M.
; Taylor, Nigel P.
; Teles, Aristônio M.
; Temponi, Lívia G.
; Terra-Araujo, Mário H.
; Thode, Veronica
; Thomas, W.Wayt
; Tissot-Squalli, Mara L.
; Torke, Benjamin M.
; Torres, Roseli B.
; Tozzi, Ana M.G.A.
; Trad, Rafaela J.
; Trevisan, Rafael
; Trovó, Marcelo
; Valls, José F.M.
; Vaz, Angela M.S.F.
; Versieux, Leonardo
; Viana, Pedro L.
; Vianna Filho, Marcelo D.M.
; Vieira, Ana O.S.
; Vieira, Diego D.
; Vignoli-Silva, Márcia
; Vilar, Thaisa
; Vinhos, Franklin
; Wallnöfer, Bruno
; Wanderley, Maria G.L.
; Wasshausen, Dieter
; Watanabe, Maurício T.C.
; Weigend, Maximilian
; Welker, Cassiano A.D.
; Woodgyer, Elizabeth
; Xifreda, Cecilia C.
; Yamamoto, Kikyo
; Zanin, Ana
; Zenni, Rafael D.
; Zickel, Carmem S
.
Resumo Um levantamento atualizado das plantas com sementes e análises relevantes acerca desta biodiversidade são apresentados. Este trabalho se iniciou em 2010 com a publicação do Catálogo de Plantas e Fungos e, desde então vem sendo atualizado por mais de 430 especialistas trabalhando online. O Brasil abriga atualmente 32.086 espécies nativas de Angiospermas e 23 espécies nativas de Gimnospermas e estes novos dados mostram um aumento de 3% da riqueza em relação a 2010. A Amazônia é o Domínio Fitogeográfico com o maior número de espécies de Gimnospermas, enquanto que a Floresta Atlântica possui a maior riqueza de Angiospermas. Houve um crescimento considerável no número de espécies e nas taxas de endemismo para a maioria dos Domínios (Caatinga, Cerrado, Floresta Atlântica, Pampa e Pantanal), com exceção da Amazônia que apresentou uma diminuição de 2,5% de endemicidade. Entretanto, a maior parte das plantas com sementes que ocorrem no Brasil (57,4%) é endêmica deste território. A proporção de formas de vida varia de acordo com os diferentes Domínios: árvores são mais expressivas na Amazônia e Floresta Atlântica do que nos outros biomas, ervas são dominantes no Pampa e as lianas apresentam riqueza expressiva na Amazônia, Floresta Atlântica e Pantanal. Este trabalho não só quantifica a biodiversidade brasileira, mas também indica as lacunas de conhecimento e o desafio a ser enfrentado para a conservação desta flora.
Abstract An updated inventory of Brazilian seed plants is presented and offers important insights into the country's biodiversity. This work started in 2010, with the publication of the Plants and Fungi Catalogue, and has been updated since by more than 430 specialists working online. Brazil is home to 32,086 native Angiosperms and 23 native Gymnosperms, showing an increase of 3% in its species richness in relation to 2010. The Amazon Rainforest is the richest Brazilian biome for Gymnosperms, while the Atlantic Rainforest is the richest one for Angiosperms. There was a considerable increment in the number of species and endemism rates for biomes, except for the Amazon that showed a decrease of 2.5% of recorded endemics. However, well over half of Brazillian seed plant species (57.4%) is endemic to this territory. The proportion of life-forms varies among different biomes: trees are more expressive in the Amazon and Atlantic Rainforest biomes while herbs predominate in the Pampa, and lianas are more expressive in the Amazon, Atlantic Rainforest, and Pantanal. This compilation serves not only to quantify Brazilian biodiversity, but also to highlight areas where there information is lacking and to provide a framework for the challenge faced in conserving Brazil's unique and diverse flora.
https://doi.org/10.1590/2175-7860201566411
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15.
Energy transfer processes in Tb(III)-dibenzoylmethanate complexes with phosphine oxide ligands
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Silva Jr., Francisco A.
; Nascimento, Helenise A.
; Pereira, Dariston K. S.
; Teotonio, Ercules E. S.
; Brito, Hermi F.
; Felinto, Maria Cláudia F. C.
; Espínola, José Geraldo P.
; Sá, Gilberto F.
; Faustino, Wagner M.
.
Journal of the Brazilian Chemical Society
- Métricas do periódico
Este trabalho relata a síntese, a caracterização e as propriedades luminescentes dos complexos de fórmulas [Tb(DBM)3L], [Tb(DBM)2(NO3)L2)] e [Tb(DBM)(NO3)2(HMPA)2)] (DBM = dibenzoilmetanato; L: TPPO = óxido de trifenilfosfina ou HMPA = óxido de hexametilfosforamida). Os compostos foram caracterizados por análise elementar (CHN), titulação complexométrica com EDTA e espectroscopia no infravermelho com transformada de Fourier (FTIR), e as propriedades de fotoluminescência foram avaliadas. As energias dos estados tripletos do ligante DBM foram determinadas experimentalmente a partir dos espectros de fosforescência resolvidos no tempo dos compostos análogos do íon Gd3+. As energias aumentam em função do número de ânions nitratos que substituem o ligante DBM nos complexos. Ademais, os espectros de luminescência e os tempos de vida dos níveis emissores revelaram que a eficiência de transferência de energia ligante-metal segue a mesma tendência. Ao contrário dos complexos tris-DBM, o bis- e o mono-DBM apresentaram elevada intensidade de luminescência, sendo candidatos promissores para camadas emissoras de luz em dispositivos moleculares conversores de luz (LCMD).
The Tb3+-β-diketonate complexes [Tb(DBM)3L], [Tb(DBM)2(NO3)L2] and [Tb(DBM)(NO3)2(HMPA)2] (DBM = dibenzoylmethanate; L: TPPO = triphenylphosphine oxide or HMPA = hexamethylphosphine oxide) were prepared and characterized by elemental analysis (CHN), complexometric titration with EDTA and Fourier transform infrared (FTIR) spectroscopy, and the photoluminescence properties evaluated. The triplet state energies of the coordinated DBM ligands were determined using time-resolved phosphorescence spectra of analogous Gd3+ complexes. The results show that the energies increase along with the number of coordinated nitrate anions replacing the DBM ligand in the complexes. The luminescence spectra and emission lifetime measurements revealed that the ligand-to-metal energy transfer efficiency follows the same tendency. Unlike the tris-DBM complexes, bis- and mono-DBM presented high luminescence, and may act as promising candidates for preparation of the emitting layer of light converting molecular devices (LCMDs).
https://doi.org/10.5935/0103-5053.20130073
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