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Within Mn-activated phosphors, the oxidation state of Mn dopant strongly depends on the structural features of the host lattice. This paper reported a new polymorph of CsMg(PO3)3 (CMP) with a complicated three-dimensional (3D) framework of [Mg(PO3)3]∞ that is constructed by MgO6 octahedra and 1D infinite [PO3]∞ chains. Then we prepared a series of red phosphors CsMg1-x(PO3)3:xMn2+ (CMP:xMn2+) by high temperature solid state reactions in the open air. Powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) studies revealed the single Mn2+-oxidation. Under 404 nm light exciting, CMP:0.2Mn2+ can emit single-band emission at around 630 nm with full-width at half-maximum (fwhm) of 70 nm. Besides, CMP:0.2Mn2+ possesses excellent thermostability up to 450 K. These features indicate that CMP:0.2Mn2+ is suitable to be used for LED backlight display. Moreover, this work suggests that a host lattice with suitable structure feature can form single Mn2+-oxidation and is rigid enough to protect Mn2+ from being oxidized by O2 at high temperature.
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A new caesium sodium samarium borate phosphate, CsNa2Sm2(BO3)(PO4)2, has been obtained successfully by the high-temperature solution growth (HTSG) method and single-crystal X-ray diffraction analysis reveals that it crystallizes in the orthorhombic space group Cmcm. The structure contains BO3, PO4, NaO7 and SmO7 polyhedra which are interconnected via corner- or edge-sharing O atoms to form a three-dimensional [Na2Sm2(BO3)(PO4)2]∞ network. This network delimits large cavities where large Cs+ cations reside to form the total structure. Under 402â nm light excitation, CsNa2Sm2(BO3)(PO4)2 exhibits three emission bands due to the 4fâ4f transitions of Sm3+. Furthermore, we introduced Gd3+ into Sm3+ sites to optimize the Sm3+ concentration and improve the luminescence intensity. The optimal concentration is Gd/Sm = 98/2. The luminescent lifetime of a series of CsNa2Gd2(1-x)Sm2x(BO3)(PO4)2 phosphors shows a gradual degradation of lifetime from 2.196 to 0.872â ms for x = 0.01-0.10. The Commission Internationale de l'Eclairage (CIE) 1931 calculation reveals that CsNa2Gd1.96Sm0.04(BO3)(PO4)2 can emit orange light under 402â nm excitation.
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For the first time, a new langbeinite-type phosphate, namely potassium terbium tantalum tris(phosphate), K2Tb1.5Ta0.5(PO4)3, has been prepared successfully using a high-temperature flux method and has been structurally characterized by single-crystal X-ray diffraction. The results show that its structure can be described as a three-dimensional open framework of [Tb1.5Ta0.5(PO4)3]∞ interconnected by K+ ions. The TbIII and TaV cations in the structure are disordered and occupy the same crystallographic sites. The IR spectrum, the UV-Vis spectrum, the morphology and the Eu3+-activated photoluminescence spectroscopic properties were studied. A series of Eu3+-doped phosphors, i.e. K2Tb1.5-xTa0.5(PO4)3:xEu3+ (x = 0.01, 0.03, 0.05, 0.07, 0.10), were prepared via a solid-state reaction and the photoluminescence properties were studied. The results show that under near-UV excitation, the luminescence colour can be tuned from green through yellow to red by simply adjusting the Eu3+ concentration from 0 to 0.1, because of the efficient Tb3+âEu3+ energy-transfer mechanism.
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An anhydrous orthophosphate, K3Eu5(PO4)6 (tripotassium pentaeuropium hexaphosphate), has been prepared by a high-temperature solid-state reaction combined with hydrothermal synthesis, and its crystal structure was determined by single-crystal X-ray diffraction analysis (SC-XRD). The results show that the compound crystallizes in the monoclinic space group C2/c and the structure features a three-dimensional framework of [Eu5(PO4)6]∞, with the tunnel filled by K+ ions. The IR spectrum, UV-Vis spectrum and luminescence properties of polycrystalline samples of K3Eu5(PO4)6, annealed at temperatures of 650, 700, 750, 800 and 850â °C, were investigated. Although with a full Eu3+ concentration (9.96 × 1021â ionsâ cm-3), the self-activated phosphor K3Eu5(PO4)6 shows s strong luminescence emission intensity with a quantum yield of 37%. Under near-UV light excitation (393â nm), the series of samples shows the characteristic emissions of Eu3+ ions in the visible region from 575 to 715â nm. The sample sintered at 800â °C gives the strongest emission and its lifetime sintered at 800â °C (1.88â ms) is also the longest of all.
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A new tantalum phosphate, tridecasodium distrontium ditantalum nonaphosphate, Na13Sr2Ta2(PO4)9, was prepared using the high-temperature flux method. The structure can be described as a three-dimensional open framework containing isolated [TaV2(PO4)9]17- units that are interlocked by Na and Sr ions. Band structure studies by the first-principles method revealed that Na13Sr2Ta2(PO4)9 is an insulator with an indirect band gap of 4.78â eV, which makes it suitable as a luminescent host matrix. A series of solid solutions, i.e. Na13Sr2-xTa2(PO4)9:xDy3+ (x = 0.01, 0.02, 0.04, 0.06, 0.08, 0.1, 0.12 and 0.14), were prepared and their photoluminescence properties studied. Under 350â nm light excitation, these emit two typical emissions of the Dy3+ ion, i.e. the 4F9/2â6H15/2 transition centred at 476â nm and the 4F9/2â6H13/2 transition centred at 570â nm.
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In order to explore the association of apolipoprotein E (ApoE) gene polymorphism with cerebral infarction in type 2 diabetic patients of Han nationality in Northeast China , the genotypes of ApoE gene were analyzed by polymerase chain reaction -restriction fragment length polymorphism (PCR-RFLP) in the 208 cases, including 69 cases in control (CON) group and 67 in type 2 diabetes mellitus (T2DM) group as well as 72 in type 2 diabetes mellitus with cerebral infarction (T2DMCI) group. Plasma lipid content in T2DMCI was also detected for 70 cases. The distribution of genotypes in ApoE gene,epsilon(2)epsilon(3),epsilon(3)epsilon(3) as well as epsilon(3)epsilon(4) was no significant difference in three groups (epsilon(2)epsilon(3) : 13.2%,epsilon(3)epsilon(3) : 67.6%,epsilon(3)epsilon(4) : 16.2%in CON group;epsilon(2)epsilon(3) : 19.4%,epsilon(3)epsilon(3): : 70.1%epsilon(3)epsilon(4) : 9%in T2DM group;epsilon(2)epsilon(3) : 15.2%,epsilon(3)epsilon(3) : 75%,epsilon(3)epsilon(4) : 4.2%in T2DMCI group). The allele frequencies of epsilon(2),epsilon(3) and epsilon(4) were not significantly different in the three groups, either(epsilon(2) : 9.6%,epsilon(3) : 82.4%,epsilon(4) : 8.1%in CON group; epsilon(2) :10.5%,epsilon(3) :84.3%,epsilon(4) : 5.2%in T2DM group; epsilon(2) :11.8%,epsilon(3) :84.7%,epsilon(4) : 3.5%in T2DMCI group). The levels of total cholesterol (TC), tryglyceride (TG), high density lipoprotein-cholesterol (HDL-C) and low density lipoprotein-cholesterol (LDL-C) were not significantly different among the different genotypes in T2DMCI group. The study confirmed that the polymorphisms of ApoE gene are neither associated with the T2DMCI, nor with the levels of plasma lipid in T2DMCI.
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Apolipoproteínas E/genética , Infarto Cerebral/genética , Diabetes Mellitus Tipo 2/genética , Polimorfismo de Longitud del Fragmento de Restricción , Infarto Cerebral/sangre , Infarto Cerebral/complicaciones , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Triglicéridos/sangreRESUMEN
By using 15 biallelic markers, 342 male individuals from six populations in China were genotyped with ASPCR (allele specific PCR). The 15 biallelic markers included M1 (YAP), M15 (9 bp insertion), M89 (C-->T), M9 (C-->G), M119 (A-->C), M50 (T-->C), M110 (T-->C), M103 (C-->T), M95 (C-->T), M88 (A-->G), M111 (2-bp deletion), M45 (G-->A), M122 (T-->C), M7 (C-->G) and M134 (1 bp deletion). The distribution of variation frequencies of 15 biallelic markers in six populations showed that with the extremely high frequencies of M9G (96.20% & 96.43%) and Han nationality displayed higher diversity than the four minority populations. It's noteworthy that M95T (82.14%) in Sichuan Han and M45A (18.57%) in Hui gave prominace to the two populations. The six populations displayed 34 (Fujian Han), 21 (Sichuan Han), 14 (Mongol), 26 (Hui), 10 (Xibo) and 8 (Hezhe) haplogroups respectively with 2, 1, 2, 1, 2 and 2 prominent haplogroups among them. Furthermore, the haplogroup analysis revealed that one predominant haplogroup was shared in the four minority populations and even two predominant haplogroups were shared in Mongol, Hezhe and Xibo. Unlike Han populations, the minority populations showed strikingly different haplogroups which were close to the ancestral pattern. However, the two Han populations exhibited divergence between them with the distinct frequencies of M89T and M95T. With the comparison of the number of people sharing the common haplogroups between any two of the four minority populations, relative genetic distance among them was deduced.
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Haplotipos , Cromosoma Y , Alelos , China/etnología , Marcadores Genéticos , Variación Genética , Humanos , Masculino , Reacción en Cadena de la PolimerasaRESUMEN
OBJECTIVE: To analyze the genetic polymorphism of 15 single nucleotide polymorphism (SNP) loci on the nonrecombining portion of the Y chromosome in 6 populations in China. METHODS: Allelic specific polymerase chain reaction and 2% agarose gel electrophoresis and 6% PAGE were used to analyze the genetic polymorphism of 343 unrelated males, representing 6 populations in China, including Fujian Hans, Sichuan Hans, Mongolian, Hezhen, Sibo and Hui from the South, Northeast and Northwest. RESULTS: Thirty haplogroups were observed, and 3 of them (H15, H16, H18) were seen in all of the six populations. Although the heterozygosity levels of the Hezhen, Mongolian, Sibo populations are similar and those of the other 3 populations (Fujian Hans, Sichuan Hans, Hui) are similar, the pairwise differences among haplogroups are significant. Analysis of molecular variance (AMOVA) and principal component (PC) analysis of the haplogroup distributions suggested highly different allele diversity between group I including Hezhen, Mongolian, Sibo and group II including Hui, Fujian Hans, Sichuan Hans. CONCLUSION: The above analyses show more significant variance components in Northeast/South populations and clearly reveal the geographic genetic relationship among the six populations in the Northeast/Northwest/South. These results confirm the complexity of the genetic structure of Chinese populations and make a significant contribution for constructing the contemporary human gene pool and tracing genetic dispersal trail from Chinese populations.
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Cromosomas Humanos Y , Polimorfismo de Nucleótido Simple , Alelos , China/etnología , Variación Genética , Genética de Población , HumanosRESUMEN
The immortal lymphoblastoid cell lines were established by EBV transformation of B cells and addition of cyclosporin A to inhibit the activity of T cells. In the present study,549 immortal cell lines of different ethnic groups of Hazak, Manchu, Korea, Hozhe, Mongolia, Sibe, Hui, Puyi, Han in Fujian and Han in Sichuan were established. Through our research,we found it is harmful for B lymphocytes to transform if excessful leucocytes are inoculated.And it is crisis that cyclosporine A shoud be added the last. Our work is an important part of the research of human genome diversity for the exploration of the origin and evolution of different ethnic groups,and it also provides enough research materials for further studies.Moreover,we have sent 50 cell lines of Hozhe, Mongolia, Sibe, Daur, Oroqen to CEPH. Thus it is possible for us to utilize the genetic resources of CEPH freely.
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Y-chromosome short tandem repeats (STRs) are potentially useful for forensic, anthropological and evolutionary studies. In this study we chose the loci DYS 19, DYS 388, DYS 389 I, DYS 389 II, DYS 390, DYS 391, DYS 392, DYS 393, DYS 425 and DYS 426. Blood samples were taken from 46 unrelated male individuals from Fujian Han and 43 unrelated males from Sichuan Han in China. DNA was extracted by conventional chelex extraction procedure. PCR was carried out in two multiplex reactions. Fragment analysis was conducted on an ABI PRISM 310 Genetic Analyzer. Allele frequency distributions and discrimination indices were calculated, and the two populations were tested for genetic differences by means of analysis of molecular variance (AMOVA). Here we obtained 75 Y-STR haplotypes and the haplotype diversity for the complete haplotype was 0.9884 in Fujian Han and 0.9967 in Sichuan Han. A larger genetic difference became apparent between the two populations that belong to the Sino-Tibetan speaking populations.