bluuebunny/crossref_metadata_2025 huggingface dataset:
Sex‐Specific Genetic Variants are Associated With Coronary Endothelial Dysfunction
Authors: Yoshino Satoshi , Cilluffo Rebecca , Prasad Megha , Best Patricia J. M. , Atkinson Elizabeth J. , Aoki Tatsuo , Cunningham Julie M. , de Andrade Mariza , Lerman Lilach O. , Lerman Amir
Published: April 2016

Background

Endothelial dysfunction is an early stage of atherosclerosis. Single‐nucleotide polymorphisms (
SNP
s) have been associated with vascular dysfunction, cardiac events, and coronary artery remodeling. We aimed to detect
SNP
s associated with endothelial dysfunction and determine whether these associations are sex specific.

Methods and Results

Six hundred forty‐three subjects without significant obstructive coronary artery disease underwent invasive coronary endothelial function assessment. We collected data from 1536
SNP
s that had previously been associated with vasoreactivity, angiogenesis, inflammation, artery calcification, atherosclerotic risk factors, insulin resistance, hormone levels, blood coagulability, or with coronary heart disease. Coronary vascular reactivity was assessed by the percent change in coronary artery diameter ≤ −20% after an intracoronary bolus injection of acetylcholine on invasive coronary physiology study.
SNP
s significantly associated with coronary epicardial endothelial dysfunction were

ADORA
1

,

KCNQ
1

, and

DNAJC
4

in the whole cohort,

LPA
,
MYBPH
,
ADORA
3

, and

PON
1

in women and

KIF
6

and

NFKB
1

in men (
P
<0.01).

Conclusions

We have identified several significant
SNP
s that are associated with an increased risk of coronary endothelial dysfunction. These associations appear to be sex specific and may explain gender‐related differences in development of atherosclerosis.
Development of Human‐Like Advanced Coronary Plaques in Low‐Density Lipoprotein Receptor Knockout Pigs and Justification for Statin Treatment Before Formation of Atherosclerotic Plaques
Authors: Li Yuxin , Fuchimoto Daiichiro , Sudo Mitsumasa , Haruta Hironori , Lin Qing‐Fei , Takayama Tadateru , Morita Shotaro , Nochi Tomonori , Suzuki Shunichi , Sembon Shoichiro , Nakai Michiko , Kojima Misaki , Iwamoto Masaki , Hashimoto Michiko , Yoda Shunichi , Kunimoto Satoshi , Hiro Takafumi , Matsumoto Taro , Mitsumata Masako , Sugitani Masahiko , Saito Satoshi , Hirayama Atsushi , Onishi Akira
Published: April 2016

Background

Although clinical trials have proved that statin can be used prophylactically against cardiovascular events, the direct effects of statin on plaque development are not well understood. We generated low‐density lipoprotein receptor knockout (
LDLR
−/−
) pigs to study the effects of early statin administration on development of atherosclerotic plaques, especially advanced plaques.

Methods and Results

LDLR
−/−
pigs were generated by targeted deletion of exon 4 of the

LDLR

gene. Given a standard chow diet,
LDLR
−/−
pigs showed atherosclerotic lesions starting at 6 months of age. When 3‐month‐old
LDLR
−/−
pigs were fed a high‐cholesterol, high‐fat (
HCHF
) diet for 4 months (
HCHF
group), human‐like advanced coronary plaques developed. We also fed 3‐month‐old
LDLR
−/−
pigs an
HCHF
diet with pitavastatin for 4 months (Statin Prophylaxis Group). Although serum cholesterol concentrations did not differ significantly between the 2 groups, intravascular ultrasound revealed 52% reduced plaque volume in statin‐treated pigs. Pathological examination revealed most lesions (87%) in the statin prophylaxis group were early‐stage lesions, versus 45% in the
HCHF
diet group (
P
<0.01). Thin‐cap fibroatheroma characterized 40% of the plaques in the
HCHF
diet group versus 8% in the statin prophylaxis group (
P
<0.01), intraplaque hemorrhage characterized 11% versus 1% (
P
<0.01), and calcification characterized 22% versus 1% (
P
<0.01).

Conclusions

Results of our large animal experiment support statin prophylaxis before the occurrence of atherosclerosis. Early statin treatment appears to retard development of coronary artery atherosclerosis and ensure lesion stability. In addition, the
LDLR
−/−
pigs we developed represent a large animal model of human‐like advanced coronary plaque suitable for translational research.
Turkey’s Relations with Greece in the 1920s: The Pangalos Factor
Authors: Emen Gözde
Published: April 2016

Based mainly on Turkish archival material and newspapers, this article argues that the short dictatorship of General Pangalos (1925–1926) in Greece not only stalled the solution of problems remaining from the Lausanne negotiations, but also heightened Turkish concerns over Greek expansionist ambitions towards Turkey in a way unlike any other period in early Turkish-Greek relations. Despite the General’s popularity among the migrants from Anatolia, the Turkish press and authorities were aware of the lack of general popular support behind Pangalos. Pangalos’s attempts to create alliances particularly with Britain and Italy and the increasing possibility of such a coalition against Turkey led the Turkish authorities and the press to watch developments in Greece very closely.
Hymenophyllum senterreanum Dubuisson & Deblauwe, sp. nov. (Hymenophyllaceae) and its relatives in western Central Africa
Authors: Dubuisson Jean-Yves , Hennequin Sabine , Droissart Vincent , Deblauwe Vincent
Published: April 2016

The fern genus Hymenophyllum (Hymenophyllaceae) so far encompassed not more than five species in western Central Africa. New investigations into BRLU and P collections on Hymenophyllaceae specimens collected in western Central Africa allowed us to identify a new species for the area. The species Hymenophyllum senterreanum sp. nov. displays indusia with an original and particular campanulate-like shape, usually observed in the distinct trichomanoid lineage. It seems endemic to sub-montane rainforests of coastal west-south Cameroon and Equatorial Guinea, and is currently known only from four localities. The novelty is considered as Endangered according to IUCN Categories and Criteria. An updated key is proposed for the genus Hymenophyllum for the region.
Synthesis of Cationic Amphiphilic Block Copolymers Poly(4-vinylbenzyltriethylammonium chloride)-b-Poly(styrene) and Their Self-Assembly in Aqueous Solution
Authors: Dong Zhijiao , Yang Bingbing , Fu Zhifeng , Shi Yan
Published: April 2016

Well defined two kinds of cationic amphiphilic block copolymers Poly(4-vinylbenzyltriethylammonium chloride)-b-Poly(styrene) are synthesized by combining reversible addition fragmentation chain transfer polymerizations and post-polymerization quaternization. Block copolymers
are characterized by GPC and 1HNMR. The self-assembly behaviors of the block copolymers are studied, which are characterized by TEM. For Poly(4-vinylbenzyltriethylammonium chloride)13-b-Poly(styrene)136, crew-cut spherical micelles are obtained by using
DMF as the initial common solvent, and the majority of the pearl series aggregates and a small amount of rod-like aggregates are all observed by using the mixture of DMF and THF as the initial common solvent. The formation process of rod-like aggregates is proposed in three steps: the micellization
of copolymer chains, the formation of pearl series aggregates from the collision and fusion of individual initial spherical micelles, and the transformation from pearl series aggregates to rod-like aggregates. For Poly(4- vinylbenzyltriethylammonium chloride)18-b-Poly(styrene)370,
large compound micelles and complicated spherical aggregates and small vesicles are all obtained. The formation process of small vesicles is also proposed in three steps: the formation of initial spherical micelles with some hydrophilic block Poly(4-vinylbenzyltriethylammonium chloride) embedded
in the core, the removing of the outer layer common solvent, and solvent nucleation in the center. It should be noted that solvent nucleation is critical, because of the hydrophilic block Poly(4-vinylbenzyltriethylammonium chloride) and the common solvent and water embedded in the core of
the initial spherical micelles.
Adsorption of Methyl Blue on Mesoporous Materials Using Rice Husk Ash as Silica Source
Authors: Nguyen Nhat Thien , Chen Shiao-Shing , Nguyen Nguyen Cong , Nguyen Hau Thi , Tsai Hsiao Hsin , Chang Chang Tang
Published: April 2016

It is recognized that recycling and reuse of waste can result in significant savings in materials and energy. In this research, the adsorption of methyl blue (MB) using waste rice husk ash (Rha) and mesoporous silica materials made from Rha (R-MCM) were analyzed. Mesoporous silica materials
were synthesized using cetyltrimethyl ammonium bromide (CTAB) as a cationic surfactant and Rha as the silica source. The prepared samples were characterized by Brunnaur-Emmet-Teller (BET) adsorption isotherm analyzer and transmission electron microscope (TEM) analysis. The results showed the
surface area of R-MCM materials was 1347 m2g−1 and the pore volume was 0.906 cm3g−1. TEM analysis showed that the mesoporous materials generally exhibited ordered hexagonal arrays of mesopores with a uniform pore size. The effects on
adsorption performance under different initial dye concentrations, different pH values and different dosages of adsorbent were also studied. Both Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms. The results show that the maximum removal efficiency
of MB more than 99%.
Hierarchically Assembled Nanofibers Created by a Layer-by-Layer Self-Assembly
Authors: Han Tae-Hwan , Lee Eun-Sook , Ko Tae-Hoon , Seo Min-Kang , Kim Hak-Yong , Kim Hyo Jung , Kim Byoung-Suhk
Published: April 2016

We report the hierarchically assembled nanofibers created by LbL self-assembly depending on the PSS-PAA fraction in the blend solutions and pH during bulid-up of the PAH/(PSS-PAA) multilayer films. The multilayer [(PEI/blend)/(PAH/blend)4] films with ρPAA
(PSS-PAA fraction in the blend solutions) = 0.0 in the blend solution exhibited surface morphologies of randomly isolated globular clusters, while at ρPAA = 0.75, worm-like morphologies were observed. Interestingly, the multilayer [(PEI/blend)/(PAH/blend)4]
films with ρPAA = 0.9 exhibited unique fibrous morphologies with the diameter of about 50 nm at narrower pH range from 3.5 to 4.2, but also the fiber diameter distribution was narrower. Based on the thickness from the X-ray reflectivity, the thickness of the one bilayer
multilayer film seemed to be 8.6 nm. The 3 bilayers multilayer film seemed to be formed as islands with very large roughness. The crystal sizes of the 3 bilayers and 5 bilayers multilayer films were about 71 nm and 123 nm, respectively. The resultant films were characterized using atomic force
microscopy (AFM) and real-time in situ X-ray scattering measurements.
Mn-Doping in NiO Nanoparticles: Defects-Modifications and Associated Effects Investigated Through Positron Annihilation Spectroscopy
Authors: Das Anjan , Mandal Atis Chandra , Roy Soma , Nambissan P. M. G
Published: April 2016

Manganese-doped nickel oxide (Ni1−xMnxO) nanoparticulate samples with x in the range 0 (undoped sample) to 0.35 were synthesized by sol–gel method involving chemical reactions between the solutions of nickel nitrate hexahydrate
and manganese acetate tetrahydrate. The nanocrystallites obtained after annealing of the precipitates for different durations were characterized by X-ray diffraction and high resolution transmission electron microscopy. The samples showed high degree of purity with no secondary phase up to
35 at.% (x = 0.35) of Mn-doping. At the initial doping concentrations, the crystallite sizes increased due to vacancy type defects being recombined with some of the doped Mn2+ ions. However, substitution-induced strain soon overtook the crystallite dynamics and the sizes
rapidly started reducing again as an indirect consequence of the necessity to accommodate majority of the doped cations on the surfaces of the nanocrystallites. There was conspicuous changes in the lattice parameter too which could again be attributed to the strain and charge effects. The
average sizes of the crystallites were obtained in the range 5.5 nm to 13.1 nm for the different samples. UV-Vis absorption studies indicated the formation of excitonic states in NiO on Mn-doping. The band gap energy (Eg) derived from the optical absorption spectra showed
a continuous increase with increase of Mn-doping of the samples. Positron lifetime and Doppler broadening spectroscopic studies were carried out on those samples to characterize the vacancy type defects and defect clusters/complexes. There were also indications to suggest positron annihilation
at the crystallite surfaces owing to their sizes of nanometer order. Positron lifetimes decreased upon increase of Mn-doping. The coincidence Doppler broadened ratio curves indicated definite shifts of the prominent oxygen-electron-annihilation peak and the variation of the lineshape parameter
S also indicated clearly the effects of Mn-doping.
Synthesis and Photoluminescence of Single-Crystalline Fe(III)-Doped CdS Nanobelts
Authors: Kamran Muhammad Arshad , Zou Bingsuo , Majid A , Alharbi Thamer , Saeed M. A , Abdullah Ali , Javed Qurat-ul-ain
Published: April 2016

In this paper, we report the synthesis and optical properties of Fe(III) doped CdS nanobelts (NBs) via simple Chemical Vapor Deposition (CVD) technique to explore their potential in nano-optics. The energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) analysis manifested
the presence of Fe(III) ions in the NBs subsequently confirmed by the peak shifting to lower phonon energies as recorded by Raman spectra and shorter lifetime in ns. Photoluminescence (PL) spectrum investigations of the single Fe(III)-doped CdS NBs depicted an additional PL peak centered at
573 nm (orange emission) in addition to the bandedge(BE) emission. The redshift and decrease in the BE intensity of the PL peaks, as compared to the bulk CdS, confirmed the quenching of spectra upon Fe doping. The synthesis and orange emission for Fe-doped CdS NBs have been observed for the
first time and point out their potential in nanoscale devices.
Hierarchical NiO Nanoflake Arrays on Nickel Foam as a Supercapacitor Electrode with High Capacitance and High Rate Capability
Authors: Yang Guangwu , He Bing , Guo Wenyue , Zhao Lianming , Xue Qingzhong , Li Hulin
Published: April 2016

In this paper, we report a simple and cost-effective method for fabricating hierarchical NiO nanoflake arrays on nickel foam. X-ray diffraction, scanning electron microscope and transmission electron microscope are employed to study the morphology and structure of the as-synthesized
NiO materials. Galvanostatic charge/discharge measurements demonstrate that the hierarchical NiO nanocomposite displays excellent capacitive behavior between the potential range of −0.1–0.5 V, and a maximum specific capacitance as high as 823 F g−1 can be achieved
at a charge/discharge current density of 4 A g−1, and it only decreases by 20% when the current density increases to 12 A g−1. The remarkable electrochemical performance of this hierarchical NiO nanocomposite indicates the great application potential in supercapacitors.
Enhanced Activity of Nanocrystalline Beta Zeolite for Acylation of Veratrole with Acetic Anhydride
Authors: Al-Turkustani Aisha Mahmood Abdulkareem , Selvin Rosilda
Published: April 2016

Friedel-Craft acylation of veratrole using homogeneous acid catalysts such as AlCl3, FeCl3, ZnCl2, and HF etc. produces acetoveratrone, (3’,4’-dimethoxyacetophenone), which is the intermediate for synthesis of papavarine alkaloids. The problems
associated with these homogeneous catalysts can be overcome by using heterogeneous solid catalysts. Since acetoveratrone is a larger molecule, large pore Beta zeolites with smaller particle sizes are beneficial for the liquid-phase acylation of veratrole, for easy diffusion of reactants and
products. The present study aims in the acylation of veratrole with acetic anhydride using nanocrystalline Beta Zeolite catalyst. A systematic investigation of the effects of various reaction parameters was done. The catalysts were characterized for their structural features by using XRD,
TEM and DLS analyses. The catalytic activity of nanocrystalline Beta zeolite was compared with commercial Beta zeolite for the acylation and was found that nanocrystalline Beta zeolite possessed superior activity.
Spectral Dependent Photoelectrochemical Behaviors of CdS Sensitized ZnO Nanorods
Authors: Majumder T , Hmar J. J. L , Roy J. N , Mondal S. P
Published: April 2016

CdS decorated ZnO nanorods have been grown by a combination of hydrothermal method and successive ion layer absorption and reaction (SILAR) method. Optical absorption and emission properties of ZnO nanorods have been studied after sensitization with CdS nanoparticles. Current–
voltage characteristics of ZnO nanorods and CdS sensitized ZnO nanorods have been studied in an electrochemical cell. The spectral dependent photocurrent and photopotential behaviors of ZnO nanorods and CdS sensitized ZnO nanorods have been investigated using monochromatic light of wavelength
300–700 nm. The photopotential recovery time have been estimated for CdS sensitized nanorods and pristine nanorods.
Radiolabeled D-Penicillamine Magnetic Nanocarriers for Targeted Purposes
Authors: Özyüncü Seniha Yolcular , Teksöz Serap , İçhedef Çiğdem , Medine E. İlker , Avcı Çığır Biray , Gündüz Cumhur , Ünak Perihan
Published: April 2016

The aim of this study is to synthesize D-Penicillamine (D-PA) conjugated magnetic nanocarriers for targeted purposes. Magnetic nanoparticles were prepared by partial reduction method and surface modification was done with an amino silane coupling agent’s (structural properties),
AEAPS, the particles were characterized by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD). After that D-PA was linked with the magnetic nanoparticles (MNPs) and has been radiolabeled with [99mTc(CO)3]+ core. Quality controls of [99mTc(CO)3-MNP-D-PA]
were established by Cd(Te) detector. The radiolabeling efficiency of magnetic nanoparticles ([99mTc(CO)3-MNP-D-PA]) was about 97.05% with good in vitro stability during the 24 hour period. As a parallel study, radiolabeled D-PA complex ([99mTc(CO)3-D-PA])
was prepared with a radiolabeling yield of 97.93%. At the end, biologic activities of binding complexes were investigated on MCF7 human breast cancer cells. Our results show that, radiolabeled magnetic nanoparticles with core [99mTc(CO)3]+ ([99mTc(CO)3-MNP-D-PA])
showed the highest uptake on MCF7 cells which were applied magnetic field in the wells. In that case, result of this study emphasizes that radiolabeled magnetic nanoparticles with core [99mTc(CO)3]+ would support new occurrences of new agents.
Synergistic Chemotherapeutic Activity of Curcumin Bearing Methoxypolyethylene Glycol-g-Linoleic Acid Based Micelles on Breast Cancer Cells
Authors: Guzzarlamudi Sofia , Singh Pankaj K , Pawar Vivek K , Singh Yuvraj , Sharma Komal , Paliwal S. K , Chourasia Manish K , Ramana M. V , Chaurasia Mohini
Published: April 2016

Although curcumin (Cur), has been poised to be an anticancer boon for quite some, its progress from bench to bed has been strained due to various pharmaceutical hurdles. Consequently curcumin has been entrapped in methoxy poly ethylene glycol and linoleic acid conjugated polymeric micelles
(PMs) to not only tackle the routine issues but to also provide a synergetic effect against MCF-7 breast cancer cells. Optimized PMs of Cur had size 186.53±12.10 nm with polydispersity index 0.143±0.031 and zeta potential −30.1±3.2 mV. Developed formulation (Mpeg-Cla-Cur
PMs) was hemocompatible and had high cytotoxicity (IC50 55.80±4.63 μg/mL) against MCF-7 cells in comparison to pure Cur suspension (IC50 75.05±5.75 μg/mL). As postulated cell cycle arrest and apoptosis studies revealed synergetic effect of Mpeg-Cla-Cur PMs with
higher cell population in G1 phase in addition to high apoptosis of MCF-7 cells as compared to pure Cur suspension and control group. Pharmacokinetic studies also show PMs enhanced MRT and T1/2 of Cur indicating its longer retention time in body. Mpeg-Cla-Cur PMs might become as an excellent
chemotherapeutic alternative candidate for treatment of breast cancer with higher commercial value.
Graphene Oxide Modulates B Cell Surface Phenotype and Impairs Immunoglobulin Secretion in Plasma Cell
Authors: Xu Shaohai , Xu Shengmin , Chen Shaopeng , Fan Huadong , Luo Xun , Yang Xiaoyao , Wang Jun , Yuan Hang , Xu An , Wu Lijun
Published: April 2016

Since discovery, graphene oxide (GO) has been used in all aspects of human life and revealed promising applications in biomedicine. Nevertheless, the potential risks of GO were always being revealed. Although GO was found to induce immune cell death and innate immune response, little
is known regarding its toxicity to the specific adaptive immune system that is crucial for protecting against exotic invasion. The B-cell mediated adaptive immune system, which composed of highly specialized cells (B and plasma cell) and specific immune response (antibody response) is the
focus in our present study. Using diverse standard immunological techniques, we found that GO modulated B cell surface phenotype, both costimulatory molecules (CD80, CD86 and especially CD40) and antigen presenting molecules (both classical and nonclassical) under the condition without causing
cell death. Meanwhile, the terminal differentiated immunoglobulin (Ig) secreting plasma cell was affected by GO, which displayed a less secretion of Ig and more severe ER stress caused by the retention of the secreted form of Ig in cell compartment. The combined data reveal that GO has a particular
adverse effect to B cell and the humoral immunity, directly demonstrating the potential risk of GO to the specific adaptive immunity.
Preparation of Reduced-Graphene Nanoribbons via One-Step Solvothermal Process
Authors: Wu Xiang-Feng , Sun Yang , Zhang Jie , Li Jing , Zhao Yong-Ke , Zhao Ze-Hua , Fu Shi-Da , Yu Xiao-Ying , Zheng Sen-Sen
Published: April 2016

Carbon nanotubes were unzipped to become reduced-graphene nanoribbons via one-step solvothermal process in a Teflon-lined autoclave. The samples were characterized by X-ray diffraction, thermo-gravimetric analysis and transmission electrical microscopy, respectively. Results showed
that the solvothermal reaction temperature played an important role in the structure of the samples. When it was 75 °C, carbon nanotubes were completely cutted into graphene oxide nanoribbons. Moreover, when it was 155 °C, they were become reduced-graphene nanoribbons. Furthermore,
the as-prepared reduced-graphene nanoribbons could improve mechanical strength of the phenolic resin/hollow glass beads foamed composites. When the reduced-graphene nanoribbons loading was 0.4 wt%, the tensile and compressive strength of the composites were increased by 19.7% and 21.3%, respectively.
Tungsten Trioxide (WO3) Nanoparticles as a New Anode Material for Sodium-Ion Batteries
Authors: Santhosha A. L , Das Shyamal K , Bhattacharyya Aninda J
Published: April 2016

Tungsten trioxide (WO3) is investigated for the first time as an anode material for sodium-ion batteries. Pristine WO3 displays a discharge potential plateau at 1 V and exhibits a 1st discharge cycle sodium storage capacity of 640 mAh g−1. Electronic
wiring of WO3 with graphene oxide (GO, 1% by weight) led to a significant increase in the storage capacity and cyclability of WO3. As a result, the discharge capacity of 1% GO-WO3 is enhanced to 927 mAh g−1 in the 1st discharge cycle. The electrochemical
intercalation of Na in to WO3 and (1%) GO-WO3 as obtained from galvanostatic charge/discharge cycling is also supported by cyclic voltammetry.
Research Based on Optical Non-Destructive Testing of Pigment Identification
Authors: Wang Jigang , Hao Shengcai , Zhou Wenhua , Qi Xiaokun , Shi Jilong
Published: April 2016

Optical Non-Destructive Testing (ONDT) can be applied as penetrating elemental and structure analysis technology in the pigments identification field. Three-dimensional video microscopy, Raman microscopy and energy dispersive X-ray fluorescence spectroscopy are employed to measure the
materials based on a Qing Dynasty meticulous painting. The results revealed that the dark yellow area within the decorative patterns was presented due to the interaction of Emerald green and hematite, and the bright yellow edge area was delineated by Cu–Zn–Pb composition. The interesting
thing is that an artificial synthetic ultramarine blue was checked in the painting. According to the first synthesized time of ultramarine blue and Paris green, the time limit of the painting completion can be identified. The principle of Pigment subtractive colorant and nitikaset method were
employed to interpreting the results. Optical testing combined with the area of cultural relic identification can be a potential method to build an expert identification system successfully. This work also help lay the optical method groundwork for further cultural relic identification, sterilization,
and preservation.
The Influence Mechanism of Halogen Ion on the Temperature Quenching Performance of Sr2SiO4:Eu Phosphors
Authors: Wang Lingli , Ni Haiyong , Zhang Qiuhong , Xiao Fangming
Published: April 2016

The luminescent properties of Sr2SiO4:Eu phosphors synthesized with and without flux have been investigated. With the co-dopation of NH4Cl, the luminescent intensity of Sr2SiO4:Eu is increased and the temperature quenching property
is improved. The effect of NH4Cl is analyzed not only from the crystallinity of the Sr2SiO4 crystal but also the band structure of Sr2SiO4 host, which is calculated by density functional method with the local density approximation.
Synthesis and Optical Properties of Eu3+ Doped NaYF4 and KYF4 Micro/Nanocrystals
Authors: Guo Siling , Cao Chunyan , Cao Renping
Published: April 2016

Through a hydrothermal method, 1 mol% Eu3+ doped NaYF4 and KYF4 micro/nanocrystals have been synthesized. The materials were characterized by X-ray diffraction (XRD) patterns, field emission scanning electron microscopy (FE-SEM) images, room temperature
photoluminescence (PL) excitation and emission spectra, and luminescent dynamic decay curves. The XRD analysis suggested the crystalline structures of the obtained samples. The FE-SEM images indicated the morphology and size of the obtained samples. The PL spectra illustrate the optical properties
of Eu3+ in the two samples. Since it is sensitive to the local environment of the ion, the Eu3+ presents different optical properties in the NaYF4 and KYF4 materials.
Decorated TiO2 Nanoparticles with La and Ag Elements to Improve Photocatalytic Activity Under Visible Light for the Degradation of MO
Authors: Wang Qinghua , Gao Xuechuan , Zhang Renfei , Shen Beibei , Tan Zhibing , Li Zhao , Yu Shiyong
Published: April 2016

Visible-light photocatalyst of TiO2/La/Ag nanocomposites were successfully synthesized via the conventional sol–gel method and reducing agent of Ag+. The photocatalytic activities were evaluated by methyl orange (MO) degradation. They have remarkable photocatalytic
activities compared to TiO2-Anatase, which is thanks to the separation of electron–hole pairs by Ag nanoparticles and lanthanum. The products were characterized by a series of techniques such as X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM),
transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and Uv-vis. The results show that spherical nanocomposites have been prepared with the size 300 nm and Ag nanoparticles (∼10 nm) are dispersed uniformly onto the surface of TiO2/La,
which forms TiO2/La/Ag nanocomposites. TiO2/La/Ag nanocomposites have good absorption in the visible region (700 nm > > > 400 nm). The reasons are as follows: (1) the efficient separation of photogenerated electrons and holes of the photocatalysts on the surface
of TiO2/La/Ag nanocomposites and (2) a wide visiblelight photoabsorption range (700 nm > > 400 nm). Therefore, this study may provide some new idea for the rational design and the facile synthesis of composite catalysts with a green, efficient pathway.
Investigation on the Synthesis and Photoluminescence of CaMoO4:Eu3+ Microspheres
Authors: Li Jinping , Zhu Gangqiang , Zhang Tingting , Zheng Hairong
Published: April 2016

Eu3+ doped CaMoO4 microspheres were synthesized via a facile hydrothermal method assisted by the citric acid additive. The structure and morphology of the samples were examined by X-ray diffractometer (XRD) and scanning electron microscopy (SEM), and the properties
of the photoluminescence emission from the samples were investigated with spectroscopic technique. The XRD results revealed that the hydrothermally formed CaMoO4:Eu3+ phosphor has single-phase scheelitetype tetragonal structure. The SEM observation demonstrated that the
samples have sphere-like morphologies and their diameters were about 3–4 μm. Meanwhile, the influence of the citric acid on the formation of CaMoO4:Eu3+ was also investigated. The formation mechanism of CaMoO4:Eu3+ microspheres was explored
based on the time-dependent experimental observation. The study on the luminescence spectra showed that CaMoO4:Eu3+ microspheres can be effectively excited at 395 nm, and good luminescence emission can be obtained at around 614 nm, which is attributed to the transition
of 5D0 →7F2 from Eu3+. The current study suggests that CaMoO4:Eu3+ red phosphor is a potential candidate for white light-emitting diodes (WLEDs) application.
Microstructure and Luminescence Properties of Tb3+ Doped ZnO Quantum Dots
Authors: Jin Na , Li Hong , Liu Fengyi , Xie Ya-Hong
Published: April 2016

In order to increase the exchange efficiency of solar cells by down-conversion, Tb3+ doped ZnO quantum dots (QDs) were successfully synthesized by sol–gel process. The X-ray diffraction (XRD) results indicate that ZnO QDs have hexagonal wurtzite structure. ZnO QDs have
a spherical shape and diameter around 5 nm, which was confirmed by high-resolution transmission electron microscopy (HRTEM). The intensity of visible light emission peaks becomes strengthened and then weakened with the increase of Tb3+ doping concentration. When the concentration
is more than 1%, because of the decrease of surface defects and concentration quenching effect, the emissive intensity is weakened. The enhancement of the PL emission peaks at 542 nm, 582 nm, and 619 nm was assigned to energy transfer between Tb3+ ions and ZnO QDs host. Moreover,
the absorption spectra also demonstrates energy transfers from Tb3+ ions to ZnO QDs.
Enhanced Photoluminescence Properties of Carbon Dots by Doping with Europium
Authors: Chen Yuan , Xu Jiafu , Liu Bitao , Li Jiyun , Fang Xiaomei , Xiong Liqiong , Peng Lingling , Han Tao , Tu Mingjing
Published: April 2016

Europium (Eu) doped carbon dots (CDs) were synthesized via a rapid and simple microwave mediated method using polyethylene glycol (PEG) as a precursor, and characterized in detail. The results were that these as-prepared CDs showed a uniform and small particle size, and exhibit good
photostability and high photoluminescence quantum yields. Additionally, it also found that the doped Eu would change the fluorescence properties, which indicates potential applications in the field of biolabeling.
Near-Infrared Quantum Cutting in Yb3+ Doped SrMoO4 Phosphors
Authors: Luo Xiaobing , Shen Jun , Huang He , Xu Lu , Wang Zhixiang , Chen Yang , Li Li
Published: April 2016

Efficient near-infrared (NIR) quantum cutting (QC) has been demonstrated in Yb3+ doped SrMoO4 phosphors synthesized by the high-temperature solid-state reaction method. The obtained SrMoO4:Yb3+ phosphors were characterized by X-ray diffraction
(XRD), diffuse reflectance spectra, photoluminescence (PL) spectra and decay lifetime to understand the observed near-infrared quantum cutting phenomena. The XRD results show that all the prepared phosphors can be readily indexed to the pure tetragonal phase of SrMoO4 and exhibit
good crystallinity. The experimental results showed that the strong visible molybdate (MoO2−24 emission around 493 nm and near-infrared (NIR) emission around 1000 nm from Yb3+(2F5/2 → 2F7/2) of SrMoO4:Yb3+
phosphors were observed under ultraviolet (290 nm) excitation. The Yb3+ concentration dependence of luminescent properties and lifetimes of both the visible and NIR emissions have also been investigated. The quenching concentration of Yb3+ ions approaches as high as 10
mol%. The cooperative energy transfer (CET) mechanism was also discussed in detail. The broadband NIR QC phosphors may possibly have potential application in enhancing the conversion efficiency of solar cells.
Color Tunable and Upconversion Luminescence in Yb-Tm Co-Doped Yttrium Phosphate Inverse Opal Photonic Crystals
Authors: Wang Siqin , Qiu Jianbei , Wang Qi , Zhou Dacheng , Yang Zhengwen
Published: April 2016

For this paper, YPO4: Tm, Yb inverse opals with the photonic band gaps at 475 nm and 655 nm were prepared by polystyrene colloidal crystal templates. We investigated the influence of photonic band gaps on the Tm-Yb upconversion emission which was in the YPO4: Tm
Yb inverse opal photonic crystals. Comparing with the reference sample, significant suppression of both the blue and red upconversion luminescence of Tm3+ ions were observed in the inverse opals. The color purity of the blue emission was improved in the inverse opal by the suppression
of red upconversion emission. Additionally, mechanism of upconversion emission in the inverse opal was discussed. We believe that the present work will be valuable for not only the foundational study of upconversion emission modification but also the development of new optical devices in upconversion
lighting and display.
Synthesis and Photoluminescence Characteristics of CaIn2O4:Dy3+ Phosphors Co-Doped with Gd3+, Zn2+ or Al3+ Ions
Authors: Gou Jing , Wang Jing , Yu Binxun , Zhang Dongyang
Published: April 2016

Novel warm-white emitting phosphors CaIn2O4:Dy3+ co-doped with Gd3+, Zn2+, or Al3+ ions were prepared by solid state reaction. In this paper, a strategy of co-doping with different ions was used with the aim of affecting
the luminescence properties of CaIn2O4:0.6%Dy3+ under NUV excitation. The luminescence intensities of CaIn2O4:0.6%Dy3+ were enhanced by 0.2% Gd3+ or 0.2% Zn2+ ions co-doping under 367 nm excitation, but
lowered by co-doping with 0.2% Al3+ ions. Furthermore, the chromaticity coordinates of CaIn2O4:0.6%Dy3+ can be tuned from the cold-white region to warmwhite region with Gd3+ or Zn2+ ions co-doping. These findings show that CaIn2O4:0.6%Dy3+,
0.2% Gd3+, and CaIn2O4:0.6%Dy3+,0.2% Zn2+ have potential application value as new warm-white LED phosphors.
Effects of Ti4+ Ions on Fluorescence Properties of Sr2CeO4:Sm3+ Phosphors
Authors: Jiao Haiyan , Wang Peiyu , Liu Liwei , Wang Yuhua
Published: April 2016

Ti4+-doped Sr2CeO4:Sm3+ phosphors were synthesized with the solid-state reaction method and the effects of doping Ti4+ on the photoluminescence properties were investigated in detail. A broad excitation band ascribed to the O2-–Ce4+
transition was observed in the range of 200 to 400 nm and with doping Ti4+ into Ce4+ sites, the intensity of charge transfer band of O2- →Ce4+ (300–370 nm) was significantly broaden and enhanced. As a result, the emission intensity of
Sr2Ce1−xTixO4 has improved about 85% by doping 0.01 mol Ti4+. White emission of −Sr2-yCe0.99Ti0.01O4:ySm3+ at y ≤ 0.03 is due the co-existence of Ce4+
→ O2- CT emission and 4G5/2–6HJ Sm3+ transitions whereas only the Sm3+ red emission prevails for 003<y≤0.15. The Sr1.99Ce0.99Ti0.01O4:0.01Sm3+
phosphor exhibited excellent color purity. Its chromaticity coordinate is measured to be (0.326, 0.322), which is close to the pure white (0.33, 0.33). The results showed that Sr1.99Ce0.99Ti0.01O4: 0.01Sm3+ phosphors could be considered
as a potential single-phase white-emitting phosphor for white light-emitting diodes.
Crystal Growth and Photoluminescence Properties of Truncated Cubic BaMgAl10O17:Eu2+ Phosphors for Three-Dimensional Plasma Display Panels
Authors: Liu Bitao , Chen Yuan , Peng Lingling , Han Tao , Yu Hong , Tian Liangliang , Tu Mingjing
Published: April 2016

Monodispersed, truncated cube BaMgAl10O17:Eu2+ phosphors were synthesized by the sol–gel process. Scanning electron microscope (SEM), photoluminescence spectrum, powder X-ray diffraction and decay curves were used to evaluate the truncated cubic
BaMgAl10O17:Eu2+ phosphors. The crystal growth process and photoluminescence properties were discussed in detail. The results showed that this truncated cubic morphology can be achieved via a simple sinter process. These truncated cubic BaMgAl10O17:Eu2+
phosphors showed acceptable emission intensity and better thermal properties. This result indicates truncated cubic BaMgAl10O17:Eu2+ phosphors would meet the requirements of plasma display panels (PDPs).
Local Environment Study of Eu3+ Doped KGd2F7 by Site-Selective Spectroscopy
Authors: Qin Yanguang , Wei Xiantao , Wen Jun , Chen Yonghu , Yin Min
Published: April 2016

The site-selective spectra and decay curves at 20 K of Eu3+ ions doped KGd2F7 were measured to study the local environment of the Eu3+ sites. The experimental results show that Eu3+ ions occupy three types of sites in the KGd2F7
host. And Eu3+ ions in different types of sites exhibit quite distinct emission spectra and have remarkably different 5D0 level decay lifetimes. Based on the intensity ratio of 5D0 → 7F2, 1 transitions of Eu3+
and the 5D0 decay lifetimes in different types of sites, the correlation between the luminescent properties and the site symmetry is discussed.
Tuning Upconversion Emission of -NaGdF4:Yb3+/Ho3+ Nanorods Through Yb3+
Authors: Gao Fangqi , Gao Wei , Wang Ruibo , Yan Longxiang , Li Jinping , Zheng Hairong
Published: April 2016

Yb3+/Ho3+ doped hexagonal NaGdF4 nanocrystals are synthesized through solvothermal method, for which pure hexagonal phased nanorods are presented. The concentration influence of Yb3+ ions on the sample morphology and fluorescence emission
of Ho3+ is investigated. It is found that the sample size is changed from 25 nm to 125 nm and the upconversion emission is tuned from green to yellow when the concentration of Yb3+ ions is increased from 5.0 mol% to 50.0 mol%. The possible upconversion mechanism and the
improvement of crystallinity are carefully investigated. It is suggested that the cross-relaxation process between Ho3+ ions promotes the red emission and quenches the green emission.
Preparation and Luminescent Properties of Sm3+-Doped High Thermal Stable Sodium Yttrium Orthosilicate Phosphor
Authors: Xue Na , Hei Zhoufei , Zhao Ze , Wang Jing , Wang Ting , Li Mengxue , Noh Hyeon Mi , Jeong Jung Hyun , Yu Ruijin
Published: April 2016

Orange-red-emitting sodium yttrium orthosilicate NaYSiO4:xSm3+ (x = 0.005, 0.01, 0.02, 0.05, 0.10, 0.15, and 0.20) were synthesized. The phase structure and photoluminescence properties of these phosphors were investigated. The emission spectrum obtained
by excitation into 406 nm contains exclusively the characteristic emissions of Sm3+ at 571 nm, 602 nm, 648 nm, and 710 nm, which correspond to the transitions from 4G5/2 to 6H5/2, 6H7/2, 6H9/2,
and 6H11/2 of Sm3+, respectively. The strongest one is located at 602 nm due to the 4G5/2 → 6H7/2 transition of Sm3+, generating bright orange–red light. The optimum dopant concentration of Sm3+
ions in NaYSiO4:xSm3+ is around 2 mol%, and the critical transfer distance of Sm3+ is calculated as 23 Å. The thermal quenching temperature is above 500 K. The fluorescence lifetime of Sm3+ in NaYSiO4:0.02Sm3+ is
1.83 ms. The NaYSiO4:Sm3+ phosphors may be potentially used as red phosphors for white light emitting diodes.
Synthesis, Photoluminescence and Bio-Targeting Applications of Blue Graphene Quantum Dots
Authors: Wang Jigang , Zhou Ji , Zhou Wenhua , Shi Jilong , Ma Lun , Chen Wei , Wang Yongsheng , He Dawei , Fu Ming , Zhang Yongna
Published: April 2016

Chemical derived graphene oxide, an atomically thin sheet of graphite with two-dimensional construction, offers interesting physical, electronic, thermal, chemical, and mechanical properties that are currently being explored for advanced physics electronics, membranes, and composites.
Herein, we study graphene quantum dots (GQD) with the blue photoluminescence under various parameters. The GQD samples were prepared at different temperatures, and the blue photoluminescence intensity of the solution improved radically as the heating temperatures increased. Concerning PL peak
and intensity of the quantum dots, the results demonstrated dependence on time under heating, temperature of heating, and pH adjusted by the addition of sodium hydroxide. After hydrothermal synthesis routes, the functional groups of graphene oxide were altered the morphology showed the stacking
configuration, and self-assembled structure of the graphene sheets with obvious wrinkles appeared at the edge structures. In addition, absorption, PL, and PLE spectra of the graphene quantum dots increase with different quantities of sodium hydroxide added. Finally, using GQD to target PNTIA
cells was carried out successfully. High uptake efficiency and no cytotoxic effects indicate graphene quantum dots can be suitable for bio-targeting.
Preparation of Fluorescent Dye-Doped Biocompatible Nanoparticles for Cell Labeling
Authors: Wang Xiaohui , Peng Hongshang , Huang Shihua , You Fangtian
Published: April 2016

In this paper, we report a series of fluorescent biocompatible nanoparticles (NPs), prepared by a facile reprecipitation-encapsulation method, for cellular labeling. The as-prepared NPs exhibit a narrow size distribution of 70–110 nm, and a core–shell structure
comprised of a hybrid core doped with different dyes and a poly-L-lysine (PLL) shell. With coumarin 6, nile red, and mesotetraphenylporphyrin as the imaging agents, the fluorescent NPs gave green, orange, and red emissions respectively. Due to the positively charged PLL shell, the fluorescent
NPs exhibit neglected cytotoxicity and efficient cellular uptake. After incubation with living cells, the results obtained by laser confocal microscope from green, orange, and red channels all clearly show that the fluorescent NPs are inhomogenously localized inside the cytoplasm without penetrating
into the nucleus. Since such PLL-modified NPs can encapsulate other hydrophobic dyes, a wide spectrum of nanoimaging agents is thus expected. Furthermore, the surface amino groups on the PLL shell afford an anchoring site for further bioconjugation, and targeted imaging is also very promising.
Enhancement of Photoluminescence in BaSi2O2N2:Eu2+ by Partial Ge4+ Substitution for Si4+
Authors: Wang Baochen , Chen Jian , Xia Yufei , Liu Yangai
Published: April 2016

Ge4+-doped BaSi2O2N2:Eu2+ phosphors were prepared by a high temperature solid-state reaction method. The phase structure, photoluminescence (PL) properties and PL thermal stability of the as-synthesized samples were investigated.
The emission intensity of the Ba(Si0.99Ge0.01)2O2N2: 0.05Eu2+ phosphor was 41.7% greater than that of BaSi2O2N2:0.05Eu2+. When the temperature increased to 150 °C, the emission
intensity of Ba(Si0.99Ge0.01)2O2N2:0.05Eu2+ phosphor was 67.0% of the initial value at room temperature. This value was 22.9% greater than that of BaSi2O2N2:0.05Eu2+. The related mechanism
has also been explained through the crystal field theory. All these results indicated that the Ge4+-doped BaSi2O2N2:0.05Eu2+ phosphor is a promising material for application in white light emitting diodes.
A New Blue-Emitting Mg2Al4Si5O18:Ce3+ Phosphor for White Light Emitting Diodes
Authors: Chen Jian , Ma Hongyun , Liu Yangai
Published: April 2016

A series of blue-emitting Mg2Al4Si5O18:Ce3+ phosphors were prepared via the conventional high temperature solid-state reaction method. The phase structure, photoluminescence (PL) properties, PL thermal stability, and fluorescence
decay curves of the samples were investigated for the first time. Under excitation at 365 nm, the phosphor exhibited a broad band blue emission with peak at 440 nm, which was ascribed to the 4f → 5d transition of Ce3+, and the color coordinate was (0.1602, 0.0849).
When the temperature increased to 150 °C, the luminescence intensity of the Mg2Al4Si5O18:0.06Ce3+ phosphor was 55.73% of the initial value at room temperature. The activation energy ΔE was calculated to be 0.25 eV, which
proved the good thermal stability of the sample. The energy transfer critical distance between Ce3+ ions in Mg2Al4Si5O18 host were also calculated. The above results indicate that the Mg2Al4Si5O18:Ce3+
is a promising candidate as a blue-emitting near ultraviolet convertible phosphor for application in white light emitting diodes (WLEDs).
Study on Fabrication and UV Photoelectric Property of TiO2 Nanotube Array Electrodes
Authors: Yao Fu , Xiao-Long Duan , Ming-Ming Xing , Xi-Xian Luo , Ying-Hui Zhang , Wang Liu
Published: April 2016

Highly ordered TiO2 nanotube array electrodes were successfully fabricated by a two-step anodization method on Ti sheet substrates in an electrolyte composed of ammonium fluoride, deionized water, and glycol. The tube wall was smooth, and the average internal and external
diameters, wall thickness, and tube length achieved were 80 nm, 90 nm, 10 nm, and 9 μm, respectively. X-ray diffraction and field emission scanning electron microscopy results revealed that the TiO2 nanotube arrays presented an amorphous structure. When calcined at 300 °C,
the arrays crystallized into the anatase phase, and the crystallization degree of the oxide layer increased as the temperature rose. Calcinating at 400 °C did not obviously disrupt the porous structure of the highly ordered arrays. However, higher temperature enlarged the diameter of the
nanotube array and roughened the tube wall. When the temperature reached 600 °C, the nanotube mouth broke because of the excessive stress, causing the oxide layer’s thinness and nanotube mouth clogging. The photoelectric test showed that the electrode presented obvious photoresponse
under 300–400 nm UV excitation (maximized at 360 nm). The degree of crystallization and the micro-structure of the oxide layer can significantly affect the photoelectric properties of the electrode. After calcination at 400 °C, the TiO2 nanotube arrays, with highly ordered
tubular structure directly connected to the Ti substrate, can ensure the rapid transportation of photo-induced electrons to the Ti substrate, while the high crystallinity of the arrays can help reduce the defect density of the nanotube and extend the lifetime of the photo-induced carriers.
The electrode showed the best photoelectric property, and the photocurrent intensity was maximized (29.6 μA). However, the calcination process with over-temperature resulted in substantial loss of the TiO2 oxide layer, mouth clogging, and a severe decline in the photoelectric
properties.