An Electroluminescent device with PVK film doped with Eu(TTA) 3 Phen and PBD was fabricated. The device structure of glass substrate/indium tin oxide/PPV/PVK∶ Eu(TTA) 3 Phen∶PBD/Alq 3/Al was employed. A sharply...An Electroluminescent device with PVK film doped with Eu(TTA) 3 Phen and PBD was fabricated. The device structure of glass substrate/indium tin oxide/PPV/PVK∶ Eu(TTA) 3 Phen∶PBD/Alq 3/Al was employed. A sharply red electroluminescence with a maximum luminance of 56.8 cd/m 2 at 48 V was achieved.展开更多
A novel iridium-complex,（BPPBI） 2 Ir（2-TFDBC）[BPPBI=2-（biphenyl-4-yl）-1-phenyl-1H-benzo[d]imidazole,2-TFDBC=1-（9-ethyl-9H-carbazol-2-yl）-4,4,4-trifluorobutane-1,3-dione],was synthesized,and its structure and c...A novel iridium-complex,（BPPBI） 2 Ir（2-TFDBC）[BPPBI=2-（biphenyl-4-yl）-1-phenyl-1H-benzo[d]imidazole,2-TFDBC=1-（9-ethyl-9H-carbazol-2-yl）-4,4,4-trifluorobutane-1,3-dione],was synthesized,and its structure and component were confirmed by 1 H NMR and element analysis,respectively.UV-Vis absorption and photoluminescent（PL） spectra of（BPPBI） 2 Ir（2-TFDBC） in dichloromethane were investigated.The Ir-complex exhibited a long wavelength excitation of 470 nm,i.e.,low-energy excitation.So,it is a promising candidate for phosphorescent probe and PL material.（BPPBI） 2 Ir（2-TFDBC）-based electroluminescent devices,ITO/MoO 3（10 nm）/NPB（80 nm）/CBP：x（BPPBI） 2 Ir（2-TFDBC）（20 nm）/TPBi（45 nm）/LiF/Al,were fabricated,where x（%） was of 4% or 8% doping concentration（mass fraction）;ITO=indium tin oxides;NBP=N,N＇-bis-（1-naphthalenyl）-N,N＇-bis-phenyl-（1,1＇-biphenyl）4,4＇-diamine,CBP=4,4＇-bis（N-carbazolyl）-1,1＇-biphenyl,TPBi=1,3,5-tris（1-phenyl-1H-benzimidazol-2-yl）benzene.The devices showed a red emission of 620 nm.The maximum current efficiency and brightness were 1.7 cd/A and 4063 cd/m 2 for a device of 8%（mass fraction） doping level,respectively.The moderate luminous efficiency was due to the inadequate energy transfer from the host material to the guest material.展开更多
The objective of the present study is to reveal the composition and characteristics of organo-mineral complexes in red soils (red soil, lateritic red soil and latosol) of south China in terms of chemical dissolution a...The objective of the present study is to reveal the composition and characteristics of organo-mineral complexes in red soils (red soil, lateritic red soil and latosol) of south China in terms of chemical dissolution and fractional peptization methods. In the combined humus, most of the extractable humus could dissolve in 0.1 M NaOH extractant and belonged to active humus (H1), and there was only a small amount of humus which could be further dissolved in 0.1 M Na4P2O7 extractant at pH 13 and was stably combined humus (H2). The H1/ H2 ratio ranged from 3.3 to 33.8 in red soils, and the proportions of both H, and total extractable organic carbon (H1+H2) in total soil organic carbon and the ratios of H1 to H2 and H1 to (H1 +H2) were all higher in lateritic red soil and latosol than in red soil. The. differences of combined humus composition in various red soils were directly related to the content of Fe and Al oxides. In organo-mineral complexes, the ratio of Na-dispersed fraction (G1) to Na-ground-dispersed fraction (G2) was generally smaller than 1 for red soils, but there was a higher G1 / G2 ratio in red soil than in lateritic red soil and latosol. G1 fraction had a higher content of fulvic acid (FA), but G2 fraction had a higher content of humic acid (HA). The ratios of H1 to H2 and HA to FA were higher in G2 than in G1. The differences in the composition and activity of humus between G1 and G2 fractions were related to the content of free Fe and Al oxides. The quantities of complex Fe and Al, the Fe/ C and Al/ C atomic ratios were higher in G2 than in G1, and the ratio of Al/ C was much higher than that of Fe/ C. It may be deduced that aluminum plays a more important role than iron in the formation process of organo-mineral complexes in red soils.展开更多
核苷酸结合寡聚化结构域(nucleotide-binding oligomerization domain,NOD)样受体家族含pyrin结构域蛋白3(nod-like receptor family pyrin domain-containing protein 3,NLRP3)炎性小体是一类位于细胞质内的多蛋白复合物,可介导多种炎...核苷酸结合寡聚化结构域(nucleotide-binding oligomerization domain,NOD)样受体家族含pyrin结构域蛋白3(nod-like receptor family pyrin domain-containing protein 3,NLRP3)炎性小体是一类位于细胞质内的多蛋白复合物,可介导多种炎症性疾病。牙周致病菌可通过活化NLRP3炎性小体,调控牙周组织的慢性炎症性反应。本文对慢性牙周炎(chronic periodontitis,CP)常见病原菌活化NLRP3炎性小体的机制进行综述,旨在为深入探索CP的发病机制提供新的思路,指导临床预防和治疗慢性牙周病。展开更多
The formation constants of Co￣(2+), Ni￣(2+), Cu￣(2+) and Zn￣(2+) complexes with humic acid (HA) and fulvicacid (FA) in red soil were determined by the potentiometric titration method. The constants as a functionof...The formation constants of Co￣(2+), Ni￣(2+), Cu￣(2+) and Zn￣(2+) complexes with humic acid (HA) and fulvicacid (FA) in red soil were determined by the potentiometric titration method. The constants as a functionof composition of the complexation solutions were obtained by two graphical approaches respectively Theformation constants decreased with increasing concentration of metal in the solution. The results provideunambiguous evidence for the heterogeneity of the function groups of humic substances. The formationconstants of FA were much smaller than those of HA, and the formation constants of Cu￣(2+) were muchgreater than those of Co￣(2+) , Ni￣(2+) and Zn￣(2+) . The potentiometric titration method for determining formationconstants are also discussed in the article.展开更多
A series of (SrNa)2-xEux(MoO4)3 red phosphors have been synthesized by using the sol-gel method. X-ray diffraction, used to characterize the crystallization process of the phosphor precursors, indicates that the (SrNa...A series of (SrNa)2-xEux(MoO4)3 red phosphors have been synthesized by using the sol-gel method. X-ray diffraction, used to characterize the crystallization process of the phosphor precursors, indicates that the (SrNa)2-xEux(MoO4)3 phosphors had an SrMoO4 structure. The properties of these resulting phosphors have also been characterized by using photoluminescence (PL) spectra. The PL results indicate that all of the (SrNa)2-xEux(MoO4)3 phosphors exhibit intense red emissions under 275, 395, and 465-nm excitation. The two strongest lines at 395 and 465 nm in the excitation spectra of these phosphors match well with the two popular emissions from near-UV and blue GaN-based light-emitting diodes. Some process parameters for Eu3+ concentration, (C6H8O7)·H2O concentration, and solution pH value were also investigated. For (SrNa)2-xEux(MoO4)3 phosphors, there are two maximum emission intensities appearing with x = 0.6 and x = 1.4, respectively. When the molar ratio of citric acid is equal to that of metal cations and the solution pH is almost 4, (SrNa)2-xEux(MoO4)3 shows the strongest emission intensity compared to those under other conditions.展开更多
Purpose: Currently, bacteriological examinations of implant treatments target periodontopathic bacteria such as red complex bacteria, including Porphyromonas gingivalis, and detect them qualitatively or quantitatively...Purpose: Currently, bacteriological examinations of implant treatments target periodontopathic bacteria such as red complex bacteria, including Porphyromonas gingivalis, and detect them qualitatively or quantitatively. However, it seems that those examinations do not reflect the peri-implant tissue conditions precisely, because periodontopathic bacteria are also frequently detected from healthy peri-implant sites. The purpose of the present study was to investigate bacteria species most involved in peri-implantitis using a PCR method. Methods: Polymerase chain reaction (PCR) primers in this study were designed based on partial sequences of 16S rDNA of bacteria species involved in peri-implantitis that were described in numerous previous studies. Peri-implant sulcus fluid (PISF) samples were collected from thirty periodontally healthy patients with implants (HI) and thirty patients with peri-implantitis (PI). Each detection frequency of bacteria species in PISFs of both groups was investigated using a PCR method, and was compared using Fisher’s exact test. Results: In PI group, detection frequencies of Corynebacterium durum, Fretibacterium fastidiosum and Slackia exigua were significantly higher than those of HI group (p P. gingivalis and Tannerella forsythia belonging to red complex were frequently detected in the PISF samples of HI group (p > 0.05). Conclusion: It was suggested that monitoring C. durum and F. fastidiosum levels in PISF samples was useful as a clinical indicator for the evaluation of peri-implant tissue conditions.展开更多
文摘An Electroluminescent device with PVK film doped with Eu(TTA) 3 Phen and PBD was fabricated. The device structure of glass substrate/indium tin oxide/PPV/PVK∶ Eu(TTA) 3 Phen∶PBD/Alq 3/Al was employed. A sharply red electroluminescence with a maximum luminance of 56.8 cd/m 2 at 48 V was achieved.
基金Supported by the Natural Science Foundation of Guangdong Province,China(No.10152404801000017)
文摘A novel iridium-complex,（BPPBI） 2 Ir（2-TFDBC）[BPPBI=2-（biphenyl-4-yl）-1-phenyl-1H-benzo[d]imidazole,2-TFDBC=1-（9-ethyl-9H-carbazol-2-yl）-4,4,4-trifluorobutane-1,3-dione],was synthesized,and its structure and component were confirmed by 1 H NMR and element analysis,respectively.UV-Vis absorption and photoluminescent（PL） spectra of（BPPBI） 2 Ir（2-TFDBC） in dichloromethane were investigated.The Ir-complex exhibited a long wavelength excitation of 470 nm,i.e.,low-energy excitation.So,it is a promising candidate for phosphorescent probe and PL material.（BPPBI） 2 Ir（2-TFDBC）-based electroluminescent devices,ITO/MoO 3（10 nm）/NPB（80 nm）/CBP：x（BPPBI） 2 Ir（2-TFDBC）（20 nm）/TPBi（45 nm）/LiF/Al,were fabricated,where x（%） was of 4% or 8% doping concentration（mass fraction）;ITO=indium tin oxides;NBP=N,N＇-bis-（1-naphthalenyl）-N,N＇-bis-phenyl-（1,1＇-biphenyl）4,4＇-diamine,CBP=4,4＇-bis（N-carbazolyl）-1,1＇-biphenyl,TPBi=1,3,5-tris（1-phenyl-1H-benzimidazol-2-yl）benzene.The devices showed a red emission of 620 nm.The maximum current efficiency and brightness were 1.7 cd/A and 4063 cd/m 2 for a device of 8%（mass fraction） doping level,respectively.The moderate luminous efficiency was due to the inadequate energy transfer from the host material to the guest material.
文摘The objective of the present study is to reveal the composition and characteristics of organo-mineral complexes in red soils (red soil, lateritic red soil and latosol) of south China in terms of chemical dissolution and fractional peptization methods. In the combined humus, most of the extractable humus could dissolve in 0.1 M NaOH extractant and belonged to active humus (H1), and there was only a small amount of humus which could be further dissolved in 0.1 M Na4P2O7 extractant at pH 13 and was stably combined humus (H2). The H1/ H2 ratio ranged from 3.3 to 33.8 in red soils, and the proportions of both H, and total extractable organic carbon (H1+H2) in total soil organic carbon and the ratios of H1 to H2 and H1 to (H1 +H2) were all higher in lateritic red soil and latosol than in red soil. The. differences of combined humus composition in various red soils were directly related to the content of Fe and Al oxides. In organo-mineral complexes, the ratio of Na-dispersed fraction (G1) to Na-ground-dispersed fraction (G2) was generally smaller than 1 for red soils, but there was a higher G1 / G2 ratio in red soil than in lateritic red soil and latosol. G1 fraction had a higher content of fulvic acid (FA), but G2 fraction had a higher content of humic acid (HA). The ratios of H1 to H2 and HA to FA were higher in G2 than in G1. The differences in the composition and activity of humus between G1 and G2 fractions were related to the content of free Fe and Al oxides. The quantities of complex Fe and Al, the Fe/ C and Al/ C atomic ratios were higher in G2 than in G1, and the ratio of Al/ C was much higher than that of Fe/ C. It may be deduced that aluminum plays a more important role than iron in the formation process of organo-mineral complexes in red soils.
文摘核苷酸结合寡聚化结构域(nucleotide-binding oligomerization domain,NOD)样受体家族含pyrin结构域蛋白3(nod-like receptor family pyrin domain-containing protein 3,NLRP3)炎性小体是一类位于细胞质内的多蛋白复合物,可介导多种炎症性疾病。牙周致病菌可通过活化NLRP3炎性小体,调控牙周组织的慢性炎症性反应。本文对慢性牙周炎(chronic periodontitis,CP)常见病原菌活化NLRP3炎性小体的机制进行综述,旨在为深入探索CP的发病机制提供新的思路,指导临床预防和治疗慢性牙周病。
文摘The formation constants of Co￣(2+), Ni￣(2+), Cu￣(2+) and Zn￣(2+) complexes with humic acid (HA) and fulvicacid (FA) in red soil were determined by the potentiometric titration method. The constants as a functionof composition of the complexation solutions were obtained by two graphical approaches respectively Theformation constants decreased with increasing concentration of metal in the solution. The results provideunambiguous evidence for the heterogeneity of the function groups of humic substances. The formationconstants of FA were much smaller than those of HA, and the formation constants of Cu￣(2+) were muchgreater than those of Co￣(2+) , Ni￣(2+) and Zn￣(2+) . The potentiometric titration method for determining formationconstants are also discussed in the article.
文摘A series of (SrNa)2-xEux(MoO4)3 red phosphors have been synthesized by using the sol-gel method. X-ray diffraction, used to characterize the crystallization process of the phosphor precursors, indicates that the (SrNa)2-xEux(MoO4)3 phosphors had an SrMoO4 structure. The properties of these resulting phosphors have also been characterized by using photoluminescence (PL) spectra. The PL results indicate that all of the (SrNa)2-xEux(MoO4)3 phosphors exhibit intense red emissions under 275, 395, and 465-nm excitation. The two strongest lines at 395 and 465 nm in the excitation spectra of these phosphors match well with the two popular emissions from near-UV and blue GaN-based light-emitting diodes. Some process parameters for Eu3+ concentration, (C6H8O7)·H2O concentration, and solution pH value were also investigated. For (SrNa)2-xEux(MoO4)3 phosphors, there are two maximum emission intensities appearing with x = 0.6 and x = 1.4, respectively. When the molar ratio of citric acid is equal to that of metal cations and the solution pH is almost 4, (SrNa)2-xEux(MoO4)3 shows the strongest emission intensity compared to those under other conditions.
文摘Purpose: Currently, bacteriological examinations of implant treatments target periodontopathic bacteria such as red complex bacteria, including Porphyromonas gingivalis, and detect them qualitatively or quantitatively. However, it seems that those examinations do not reflect the peri-implant tissue conditions precisely, because periodontopathic bacteria are also frequently detected from healthy peri-implant sites. The purpose of the present study was to investigate bacteria species most involved in peri-implantitis using a PCR method. Methods: Polymerase chain reaction (PCR) primers in this study were designed based on partial sequences of 16S rDNA of bacteria species involved in peri-implantitis that were described in numerous previous studies. Peri-implant sulcus fluid (PISF) samples were collected from thirty periodontally healthy patients with implants (HI) and thirty patients with peri-implantitis (PI). Each detection frequency of bacteria species in PISFs of both groups was investigated using a PCR method, and was compared using Fisher’s exact test. Results: In PI group, detection frequencies of Corynebacterium durum, Fretibacterium fastidiosum and Slackia exigua were significantly higher than those of HI group (p P. gingivalis and Tannerella forsythia belonging to red complex were frequently detected in the PISF samples of HI group (p > 0.05). Conclusion: It was suggested that monitoring C. durum and F. fastidiosum levels in PISF samples was useful as a clinical indicator for the evaluation of peri-implant tissue conditions.
