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All-solid-state batteries greatly rely on high-performance solid electrolytes. However, the bottlenecks in solid electrolytes are their low ionic conductivity and stability. Here we report a new series of amorphous xAgI·(1-x)Ag3PS4 (x = 0~0.8 with interval of 0.1) conductors, among which the sample with x = 0.8 exhibits the highest ionic conductivity (about 1.1 × 10-2 S cm-1) and ultrahigh chemical stability. We discovered the existence of mixed disordered Ag3PS4 and AgI clusters in the amorphous conductors using solid-state nuclear magnetic resonance spectroscopy. The high ionic conductivity was ascribed to the formation of the interconnecting AgI clusters, i.e., the percolative channels for superionic conduction. The composition dependence of the ionic conductivity for this series of amorphous conductors was clarified by a continuum percolation model. These findings provide fundamental guidance for designing and fabricating high-performance amorphous solid electrolytes for all-solid-state batteries.

In this paper, η-biharmonic hypersurfaces with constant scalar curvature in 5-dimensional pseudo-Riemannian space forms are studied. We prove that such hypersurfaces with diagonalizable shape operator have constant mean curvature, which gives an affirmative partial answer to the conjecture in [Arvanitoyeorgos, A.—Kaimakamis, F. G.: Hypersurfaces of type $\begin{array}{} \displaystyle M^3_2 \end{array}$ in $\begin{array}{} \displaystyle \mathbb{E}^4_2 \end{array}$ with proper mean curvature vector, J. Geom. Phys. 63 (2013), 99–106]. As a result, we give several partial classification results.

Understanding the role of network formers in affecting the electrochemical performances of the glass anodes for Li-ion batteries (LIBs) is of great importance for developing novel glass anode materials. In this work, we substitute the network former P2O5 for partial amount of TeO2 in V2O5-TeO2 glass composition and probe the effect of this substitution on both the microstructure and performances of the LIB anodes. The network structure of the glass before and after discharging/charging cycles is revealed at atomistic level by advanced Solid-State Nuclear Magnetic Resonance spectroscopy and X-ray photoelectron spectroscopy. The results show that, upon the insertion/extraction of Li+ ions, the structural network of the glass anode is irreversibly disassociated into many short polyhedral species that congregate to form different kinds of nanoclusters. The substitution of P2O5 for TeO2 promotes the formation of Li2Te and the reduction of V5+ to V4+, and thereby enhances the capacity of the glass anodes.

Fluorophosphate glass-ceramics containing Ba2LaF7:Er3+ nanocrystal upconversion-luminescent materials were prepared via a melt-quenching method, followed by heat treatment. The glass structure evol...

A series of glasses with composition 60NaPO3–(40-x)CdF2–xYF3–yEr2O3 were synthesized via melt-quenching methods and subsequently heat-treated to obtain upconversion luminescent glass ceramics conta...

Oxynitride phosphate glasses are a subfield of phosphate-based glasses, where part of the oxygen of the network has been replaced by nitrogen, in a process commonly called nitridation, of the phosp...

Glasses in the xLa2O3-yAl2O3-(100 – x – y)NaPO3 system were synthesized by a melt quenching method, where 0 ≤ x ≤ 7.5, y = 0 and x = 5, 5 ≤ y ≤ 15. The structures were characterized by advanced mul...

We studied the effect of silicon doping on the structure and crystallization behavior of 50V2O5-50TeO2 (mol%) (VT) glass by performing solid-state nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). We observed two interesting phenomena. First, when the mixture of glass and Si is heated in argon to 560 K (1.1Tg), Si starts to react with VT glass and is oxidized to amorphous silica, being confirmed by NMR and FTIR. Second, Si suppresses the formation of the Te2V2O9 phase in VT glass during heating process up to 650 K (about 1.3Tg), whereas it leads to the formation of the new crystalline phase TeVO4 during heating to 725 K (1.4Tg). We discuss the origin of these two phenomena by considering the changes both in glass structure and in the redox reaction.

The development of high-power white light-emitting diodes demands highly efficient and stable all-inorganic color converters. In this respect, phosphor-glass/ceramic composites show great promise as they could combine the merits of high quantum efficiency of phosphors and high chemical and thermal stabilities of glass/ceramic matrices. However, strong interfacial reaction between phosphors and matrices at high temperature results in quantum efficiency loss of the embedded phosphors, and traditional solutions rely on high-pressure consolidation techniques. Here we report the intrinsic inhibition of interfacial reaction by using silica glass rather than multicomponent glasses as the matrix. The embedment of phosphors is achieved via a pressureless sintering method, rendering these color-tunable phosphor-glass composites not only accessible to three-dimensional printing technique, but also highly efficient (internal quantum efficiency >90.0%), thermally stable at 1200 °C and hydrothermally stable at 200 °C. Our results provide a facile and general strategy for developing all-inorganic functional composites., Phosphor-glass/ceramic composites are attractive for high-power white light-emitting diodes, but interfacial reaction leads to loss of quantum efficiency. Here the authors report a reduction sintering method for embedment of phosphors into silica glass with limited interfacial reaction.

Recently, metal-organic frameworks (MOFs) have been confirmed to be stable in a vitreous state, thus stimulating growing interest in the discovery of the physicochemical properties of these newly explored types of glasses. Herein, we examine the nonlinear-optical (NLO) response of Zn- and Zn-Co-based zeolitic imidazolate framework-62 (ZIF-62) glasses using an open-aperture Z-scan technique. We reveal that the Zn-ZIF-62 glass does not characterize a saturable absorption feature (1030 nm femtosecond laser) owing to its low optical absorption in the near-infrared (NIR) spectral region. In contrast, a NIR absorption band (1100 nm) has been observed in Zn-Co-ZIF-62 glass, which exhibits a strong NLO response with a high modulation depth of 63.85%. We attribute the observed NLO response to transient saturation of the 4T1(4F) level of Co ions upon femtosecond laser excitation. The intriguing NLO properties of this MOF glass may enable potential applications in the photonics fields for sensing and optical modulation.

The detailed local structures of fluoroborosilicate glasses with the compositions of (50+x)SiO2–(20-x)B2O3–10Na2O–10NaF–10YF3 (x = 0, 5, 10, 15 mol%) were investigated by advanced one- and two- dim...

Glass samples with the stoichiometric components of 20LiCl–40Li2O–(80–x)­PO5/2–xMoO3 (x = 0, 10, 20, 30, 40, 50, 60, and 70) are synthesized. The dependence of ion conductivity on structure is investigated. The structures of these glasses are investigated by Raman and solid-state nuclear magnetic resonance (NMR) spectroscopy. The phosphorus structure unit Q(n)mMo species (where n represents the number of P–O–P linkages in per phosphorus species, while m denotes the number of P–O–Mo linkages) are identified by 31P 2D J-resolved and magic angle spinning NMR spectra. With the increase of MoO3, the phosphorus chains are broken into dimer phosphorus Q(1)0Mo and orthophosphate Q(0)1Mo species successively. Raman shows that both 4- and 6-coordination molybdenum exists in the glasses. In the glasses with x > 20, 6-coordination molybdenum becomes dominated. With the replacement of P by Mo, a large number of Li+ ions transfer from the phosphorus phases into molybdenum phases, resulting in an enhancement of the ionic conductivity. When the substituted amount (x) is 70, the ionic conductivity can be increased by about 250 times, i.e., reaches 1.05 × 10–5 S·cm–1.

Oxyfluoride glasses in the systems (55 – x)SiO2–(15 + x – z)Al2O3–zLa2O3–10CaO–20CaF2–yErF3 (x = 0, 5, 10, 15; y = 0.5, 1, 1.5; z = 0, 2, 5 mol %) were prepared by conventional melt-quenching metho...

We prepared four Er3+-Yb3+ co-doped oxyfluoride precursor glass (PG) samples with the same chemical composition at different melt-homogenization temperatures (Thomo), respectively, at the same melt-quenching rate. We investigated the effect of Thomo and heat-treatment (HT) on the crystallization, structure, and optical properties of the four samples. The results show that the structural heterogeneity in the PG sample increases with lowering Thomo, and this promotes phase-separation, and hence, formation of Ba2LaF7 crystals. Consequently, the light transmittance of PG samples is decreased, but the up-conversion (UC) luminescence is enhanced. Moreover, the crystallinity of the four PG samples was increased by HT, and this altered the light transmittance, and greatly enhanced the UC luminescence. The mechanism of these discovered phenomena was discussed in terms of structure and crystal evolution. This work provides an effective way to optimize the optical and photonic performances of the rare earth doped oxyfluoride glass-ceramics.

A series of glasses with composition 60NaPO

The relationship between the luminescence properties and the glass structure of Nd3+-doped CaO-Al2O3-(B2O3, SiO2, or Ga2O3) glasses are investigated. The luminescence properties of CaO-Al2O3-B2O3 system are twice as much as that of the CaO-Al2O3-(SiO2 or Ga2O3) system. The glass structure and the coordination environment of the Nd3+ ions were investigated using nuclear magnetic resonance, Raman and electron paramagnetic resonance spectroscopy. All Al, Ga, and Si atoms are four coordinated. The B atoms have three- and four-coordinated boron units, however, most of them are three coordinated. The hyperfine sublevel correlation spectra reveal that the Al and B nuclei are in the coordination sphere of Nd3+ ions for aluminoborate glasses; however, only 27Al signals could be observed for aluminosilicate and aluminogallate glasses. Owing to the increased number of AlO4-BO3 connections and 11B nuclei around the Nd3+ ions, B has a significant effect on the luminescence properties of the Nd3+ ions. The increase in GaO4 or SiO4 does not change the three dimensional-tetrahedral network, and the coordination environment of Nd3+ ions varies slightly. Thus, the effect of Ga2O3 and SiO2 on the luminescence properties of the Nd3+ ions is not as great as that of B2O3.

A series of 16BaF2–(84 − x)NaPO3–xYF3–yErF3 (x = 0, 12, 24, 36, and 48 mol%; y = 0.1, 0.5, and 1 mol%) glasses were prepared via the conventional melt-quenching method and subsequently heated to synthesize glass ceramics containing Er3+-doped Na5Y9F32 crystals. The structures of glasses and glass ceramics were characterized by multiple advanced one- and two-dimensional solid-state magic angle spinning nuclear magnetic resonance (MAS NMR) techniques. At the atomic level, multiple phosphorus species Qn (n = 0, 1, and 2) were resolved. Here, the value n denotes the number of P–O–P bonds, which can be quantified by 2D J-resolved spectroscopy. The connectivity between F− ions and cations was detected by the rotational echo double resonance (REDOR) and the J-coupling based heteronuclear multiple quantum coherence (HMQC) method. With the increase of YF3 content, the phosphate network depolymerized gradually. 31P and 19F MAS spectra, as well as 23Na {31P} and 23Na {19F} REDOR results, consistently proved that Y3+ ions, replacing partial Ba2+ and Na+ ions, aggregated around phosphorus tetrahedrons [PO4]3−, whereas partial Ba2+ and Na+ ions moved away from [PO4]3− to bond with F− ions and formed Y–F⋯Na and Ba–F⋯Na linkages. All cations could exist as oxygen and fluorine complex ligand units M(OxFy), besides single oxygen ligand units M(Ox+y), where M represents cations in glasses. When YF3 content reached 48% by mole, micro-regions enriched in Y–F⋯Na linkages were formed, which promoted the crystallization. 31P MAS spectra indicated that the crystallization of Na5Y9F32 crystals has not affected the local structure of phosphorus species. Intensive upconversion luminescence can be observed in the fluoro-phosphate glass ceramics containing Er3+:Na5Y9F32 crystals. On the basis of these complementary evidences from solid-state NMR experiments and luminescence spectra, a novel structure evolution model during crystallization is developed.

It is known that the optical transparency of an oxide glass decreases with an increase in the size and fraction of crystals in the glass during heat-treatment. Here, the authors report an opposite scenario, where a translucent Er3+−Yb3+ doped oxyfluoride precursor glass-ceramic (P-GC) becomes transparent with increasing crystal size and crystallinity. Specifically, in the heat-treated P-GC samples, the authors observe that the growth of the existing Ba2LaF7 crystals and particularly the formation of small spherical Ba2LaF7 crystals greatly enhanced the light transmittance. To reveal the origin of this anomalous phenomenon, the authors perform detailed morphology and structure analyses on both P-GC and the heat-treated P-GC samples and molecular dynamics simulations of the precursor glass. The results show that the composition of the residual glass phase is altered (e.g., depletion of La3+) in the way that the differences in refractive index between the glass matrix and the crystals are greatly reduced. As a consequence, the light scattering of the heat-treated P-GC is suppressed, and hence, the derived P-GC becomes transparent. In addition, a proper heat-treatment can also enhance the luminescence of the studied P-GC system.

Time‐restricted feeding (TRF), that is, no caloric intake for 14‐16 hours each day leads to favourable nutritional outcomes. This study is the first to investigate TRF through a surgical perspective verifying its efficacy against liver ischaemia reperfusion (I/R) injury. We randomly assigned 100 10‐week‐old wild‐type male C57BL/6 mice into two feeding regimens: TRF and ad libitum access to food. Main outcomes were evaluated at 6, 12 and 24 hours post‐I/R surgery after 12 weeks of intervention. TRF group demonstrated minor liver injury via histological study; lower serum levels of liver enzymes, glucose and lipids; higher concentrations of free fatty acid and β‐hydroxybutyrate; decreased oxidative stress and inflammatory biomarkers; as well as less severe cell apoptosis and proliferation. Further exploration indicated better gut microenvironment and intestinal epithelial tight junction function. TRF employed its positive influence on a wide spectrum of biochemical pathways and ultimately revealed protective effect against hepatic I/R injury possibly through adjusting the gut microbiota. The results referred to a strong indication of adopting better feeding pattern for surgical patients.

LaF3 and NaLaF4 crystals were selectively precipitated in the SiO2-Al2O3-AlF3-Na2O-NaF-LaF3-ErF3 glass system by adjusting their compositions. The structural evolution at the atomic level driven by heat treatment and glass compositions was studied using the state-of-the-art magic-angle spinning nuclear magnetic resonance technique. From a comprehensive local structural study, we found that LaF3 and NaLaF4 crystals compete in crystallization in these glasses. The crystallization ability of NaLaF4 increases with the increase of the content of Na+ ions within the F-enriched phase, but for LaF3 crystals, it is reverse. These two crystals can be selectively precipitated in the glasses by adjusting the content of these Na+ ions within the F-enriched phase. When the crystallization ability of these two crystals becomes similar, none of them can be precipitated due to their mutual interference in crystallization. Intense single green upconversion luminescence occurs in glasses precipitating LaF3 or NaLaF4 crystals. The underlying relationship between compositions, structures, crystallization, and upconversion luminescence properties is unearthed based on the structural evolution, crystallization mechanism, and luminescence properties. This relationship will facilitate the compositional design of these kinds of glasses. It is inferred that it will be better to precipitate LaF3 rather than NaLaF4 crystals for achieving highly efficient upconversion luminescence.

Rare earth ion-doped oxyfluoride glasses in the system 50SiO2–(50 – x)PbO–xPbF2–mLa2O3–nEr2O3 were prepared by the melt-quenching method. PbF2 and LaF3 were selectively crystallized by subsequent h...

Recently it has been demonstrated that the electrochemical performances of semiconducting amorphous anodes for Li-ion batteries (LIBs) can be greatly enhanced by the discharging/charging induced nanocrystals. However, the structural origin of those nano-domains remains elusive, although it is critically important for designing superior glass anodes for LIBs. In this work, we probe the local structural evolution in a glass anode for LIBs during cycles by means of the state-of-the-art solid-state nuclear magnetic resonance (SSNMR). The structural evolution is manifested as the disassociation of the structural network into isolated units, followed by formation of different types of nano-domains with a high degree of order. These domains are highly favorable for rate capability and long-term cycling stability. From SSNMR and electrochemical characterizations, we have obtained a clear picture about the detailed redox reactions. These findings provide a chemical principle that is helpful for designing the stable glass electrodes for high-performance LiBs.

Borosilicate glasses have been in widespread use for over a century; however, a detailed understanding of the structural response to densification is still lacking. In this work, two commercial borosilicate glasses, viz., SCHOTT N-BK7® (N-BK7) and Borofloat33® (Boro33), are hot compressed up to 2 GPa with nitrogen gas, and the structural response to this densification is explored via 11B solid-state nuclear magnetic resonance (NMR) spectroscopy and classical molecular dynamics (MD) simulations. The molar volume (Vm) of N-BK7 and Boro33 decreases ~5% and ~10%, respectively, as a result of hot compression at 2 GPa. The NMR results demonstrate the presence of three different types of fourfold coordinated boron species (B[4]), which are confirmed in MD simulations to be (Formula presented.) (0B,4Si[4]), (Formula presented.) (1B[3],3Si[4]), and (Formula presented.) (1B[4],3Si[4]) (where subscripts represent different B[4] types and brackets indicate the next nearest neighbors (NNN)). The NMR results also show that the fraction of B[4] increases by ~13% in N-BK7 glass upon hot compression at 2 GPa via the trigonal boron to tetrahedral boron (B[3] to B[4]) conversion, while the fraction of B[4] in Boro33 glass only increases by ~2% at the same pressure, despite the fact that the Vm decrease in N-BK7 is double that of Boro33. The MD simulations capture the experimental trends in B[4] populations, despite an underestimation of the B[4] increase of N-BK7 (only ~6%) at 2 GPa. Moreover, the MD simulations suggest that the Vm reduction is a linear function of bond angle change and the fraction of Si-O-Si and B[4]-O-Si. The modifiers and boron coordination conversion also influence the volume densification of borosilicate glasses by increasing the difficulty of bond bending, decreasing the bond lengths, and increasing the population of B[4]-O-Si linkages. Finally, the B[4] to B[4] conversion, that is, (Formula presented.) (1B[3],3Si[4]) and (Formula presented.) (1B[4],3Si[4]) to (Formula presented.) (0B,4Si[4]), is observed in hot compressed N-BK7 and Boro33 from NMR and qualitatively confirmed in MD.

Background Time-restricted feeding regimen (TRF), that is, no food consumption for 14–16 h during the light phase per day, attenuates the fattening traits and metabolic disorders in adults. This study aims to further investigate whether TRF would be protective against similar nutritional challenges in juvenile mice. Methods Mice in the experimental group were treated with TRF during the first 4 weeks (considered to be the childhood phase of mice) before switching to ad libitum (AD) feeding pattern as adults; the control group with all subjects sticks to AD mode. Body weight was monitored, and serum biochemistry, sexual maturity, immune function, and gut microbiota were assessed at a certain timing. Results Mice treated with TRF during the childhood period (from weaning age) but went through AD feeding pattern as adults demonstrated the tendency of higher body weight, higher levels of serum glucose, shrunken Langerhans islets, fatty liver disease, thickening of aortic walls, delayed sexual development, increased proportion of T regulatory cells, and unhealthy gut microbiota. Conclusion Childhood TRF causes pleiotropic adverse effects, including severe irreversible metabolic disorders, depressed immune function, and retarded puberty. Microbiota set the stage for TRF to employ downstream reactions on the above changes.

Yb3+/Al3+/P5+-co-doped silica glasses with different P/Al ratios were prepared using the sol-gel method combined with high-temperature sintering. The evolution of composition-dependent color centers caused by X-ray irradiation in these glasses was correlated with their structural changes, which are controlled by the P/Al ratio. Nuclear magnetic resonance (NMR) and Raman spectra have been used to characterize the glass network structure, and advanced pulse electron paramagnetic resonance (EPR) has been employed to study the local coordination atomic structures of Yb3+ ions in pristine glasses as a function of the P/Al ratio. Si- (Si-E'), Al- (Al-E', Al-ODC, AlOHC), P- (P1, P2, POHC), and Yb-related (Yb2+) color centers in irradiated glasses have been observed and explained by optical absorption and continuous wave-EPR spectroscopies. The formation mechanisms of these centers, the structural models of glasses, and the relationship between them were proposed. Direct evidence confirms that the formation of Yb2+ ions induced by radiation is highly dependent on the coordination environment of Yb3+ ions in glasses. In addition, the glass network structure significantly affects the generation of oxygen hole color centers (AlOHCs/POHCs) caused by radiation. These results are useful in understanding the microstructural origin and the suppression mechanism of the radiodarkening effect by phosphorus co-doping in Yb3+-doped silica fibers.

Highly Yb-doped silica glass with low refractive index for fabrication of Yb-doped large-mode-area photonic crystal fiber (LMA PCF) is in favor of decreasing fiber length and thus increasing the threshold of nonlinear effects in pulse laser amplification. Accordingly, fluorine incorporation in highly Yb-doped silica glass is vitally important to compensate the sharp increase in refractive index caused by ytterbium and aluminum ions. In this work, the fluorine doping concentration in Yb/Al/P/F co-doped silica glass was significantly improved by a modified sol-gel method combined with high temperature sintering. The effects of fluorine doping on glass structure have been investigated in details by Raman spectra, nuclear magnetic resonance (NMR) and advanced pulse electron paramagnetic resonance (EPR) measurements. The incorporation of fluorine yields Si-F bonds and Yb-F bonds formation and leads to the mild change in spectroscopic properties. An optimized silica core glass rod with high Yb (0.77 wt.%) and fluorine (0.8 wt.%) doping concentration, low refractive index and acceptable optical quality was prepared. Based on the highly fluorine and ytterbium doped silica core glass, a polarization maintaining (PM) photonic crystal fiber with 40 µm core was prepared and the pump absorption coefficient at 976 nm was ∼6.5 dB/m. An average amplified power of 103 W was achieved from a 2-m-long PCF with the bend diameter of 23 cm. The slope efficiency (with respect to pump power) was 52% with laser beam quality factor M2 of 1.46.

[EN] Effects of substitutions of SiO2for Al2O3and P2O5in a single base phosphate glass, Nd3þ:P2O5-Al2O3-Li2O-MgO-Sb2O3, on glass structure and properties are investigated. For glasses with Al2O3replaced bySiO2, coordination number of Al becomes larger, and P]O bond and Si with six oxygens coordinatedemerge. For glasses with P2O5replaced, coordination number of Al becomes smaller, P(Q2) changes toP(Q1) and all Si units are four coordinated. The reason for coordination number of Al and Si change maycome from the variation of terminal oxygen quantity. The relationship between glass structure andphysical (r,Tg, CTE), mechanical (E), and optical properties (nD,sem,Dlem) are builded., Xin Wang thanks funding from project J-GFZX0205010501.7.Franscico Muñoz thanks funding from projects MAT2013-48246-C2-1-P from MINECO of Spain and I-link+0959 from CSIC.

Borosilicate glasses doped with PbSe quantum dots (QDs) were prepared by a conventional melt-quenching process followed by heat treatment, which exhibit good thermal, chemical and mechanical stabilities, and are amenable to fiber-drawing. A broad near infrared (NIR) photoluminescence (PL) emission (1070–1330 nm) band with large full-width-at-half-maximum (FWHM) values (189–266 nm) and notable Stokes shift (100–210 nm) was observed, which depended on the B2O3 concentration. The PL lifetime was about 1.42–2.44 μs, and it showed a clear decrease with increasing the QDs size. The planar [BO3] triangle units forming the two-dimensional (2D) glass network structure clearly increased with increasing B2O3 concentration, which could accelerate the movement of Pb2+ and Se2- ions and facilitate the growth of PbSe QDs. The tunable broadband NIR PL emission of the PbSe QD-doped borosilicate glass may find potential application in ultra-wideband fiber amplifiers. This article is protected by copyright. All rights reserved.

The study aims at understanding the structural role of P2O5 in meta- and per-aluminous sodium aluminosilicate glasses, followed by its correlation with their crystallization behavior. Experimental results suggest an increase in the degree of polymerization of the phosphate network and a change in the aluminum environment in the glasses from Al(OSi)4 to Al(OP)4 with an increasing P2O5/SiO2 ratio. The substitution of SiO2–by–P2O5 in the amount varying between 10 – 20 mol.% suppresses the crystallization of nepheline. This has been attributed to the unavailability of Al3+ (to form Si–O–Al linkages) due to the formation of Al–O–P linkages in the glass structure. An increase in P2O5 content (>20 mol.%) in peraluminous glasses results in the crystallization of AlPO4 as the primary phase. The results have been discussed in the light of various models developed to predict the compositional dependence of nepheline crystallization in Hanford's high-level waste glasses.

Water-soluble hexagonal NaScF 4 :Yb/Er upconversion microcrystals (UCMCs) were synthesized using the hydrothermal method. The upconversion photoluminescence properties of NaScF 4 :xYb/2%Er microcrystals (x = 4–20%) were characterized under a 980-nm-wavelength laser excitation. The dependence of red/green (R/G) ratio on the concentration of Yb 3+ ions was investigated. The local environments of dopant ions (Yb 3+ , Er 3+ ) in NaScF 4 were studied using multiple solid-state nuclear magnetic resonance (NMR) techniques. The 19 F single pulse and 19 F{ 23 Na} and 19 F{ 45 Sc} rotational echo double resonance (REDOR) techniques proved that the dopant rare-earth ions (Yb 3+ , Er 3+ ) preferred to substitute Na + rather than Sc 3+ ions. Such solid-state NMR techniques provide a novel approach to study new phosphors.

In this Article, large enhancement in upconversion (UC) luminescence was verified in a transparent aluminosilicate glass-ceramics (GCs) containing CaF2 nanocrystals (NCs) codoped with Er3+ and Yb3+ ions. On the basis of the joint spectroscopic and structural characterizations, we suggest that the precipitation of fluoride NCs is correlated with the pre-existence of the fluoride-rich domains in the as-melt glass, which is supported by scanning transmission electron microscopy (STEM) and reproduced by molecular dynamics (MD) simulation. The precipitation of the fluoride NCs starts from a phase-separated as-melt glass consisting of fluorine-rich and oxygen-rich domains, while the spatial distribution of rare earth (RE) ions and the vibration energies of the bonds connecting RE ions remain almost unchanged after crystallization. In the GCs, both the fluoride domain and the oxygen-containing polyhedrons surrounding RE ions experience significant ordering, which may affect the UC emission for both glasses and G...

Novel gallium-doped amorphous calcium phosphate (ACP) nanoparticles with different (Ga + Ca)/P molar ratio (1.8–3.0) were synthesized using sol-gel method. The antibacterial effects of the gallium-doped ACP samples were tested using disk diffusion assays, against Pseudomonas aeruginosa . The results showed that the gallium-doped ACP samples have obvious effect of inhibiting the growth of Pseudomonas aeruginosa and could have a long term antibacterial properties. The local structures of these amorphous calcium phosphate nanoparticles were studied by 31 P, 71 Ga single pulse, double-resonance and 31 P homonuclear dipolar recoupling solid state NMR techniques. The solid state NMR studies indicate that gallium-doped ACP nanoparticles are consisted of Ga x (OH) y O z and calcium phosphate clusters. Gallium-doped ACP nanoparticles could be promising complex materials with the properties of antibacterial and biological mineralization.

Glasses in the system xBi2O3–(100 – x)NaPO3 were prepared using transitional melting–quenching and characterized using solid state nuclear magnetic resonance (SSNMR), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FT-IR). The addition of Bi2O3 results in the depolymerization of the phosphorus chain and the formation of Q(n) (n = 0, 1, 2) phosphorus species, where n represents the number of P–O–P bonds that can be quantified using 31P magic angle spinning (MAS) NMR and constant-time double-quantum based dipolar recoupling effects nuclear alignment reduction (CT-DQ-DRENAR). The 23Na{31P}, 31P{23Na}, and XPS results consistently prove that both Na+ and Bi3+ ions are bounded by phosphorus tetrahedron [PO4]3–. Unlike other trivalent ions such as Ga3+ and Al3+, which connect with the phosphorus tetrahedron by corner-sharing, Bi3+ ions were first proved to share edge with the phosphorus tetrahedron by the analysis of 31P spectra, taking the charge balance and bond valence co...

The structure of glasses in the systems (100 – x)B2O3–xPbF2 (x = 30, 40, and 50) and 50B2O3–(50 – x)PbO–xPbF2 (x = 5, 10, 15, 20, 25, 30, 35, 40, and 45) has been studied by solid state NMR and EPR spectroscopies. On the basis of 11B and 19F high resolution solid state NMR as well as on 11B/19F double resonance results, we develop a quantitative structural description on the atomic scale. 19F NMR results indicate a systematic dependence of the fluoride speciation on PbF2 content: At low x-values, F– ions are predominantly found on BO3/2F– units, whereas, at higher x-values, fluoride tends to be sequestrated into amorphous domains rich in PbF2. In addition, both pulsed EPR studies of Yb3+ doped glasses and photophysical studies of Eu3+ doped samples indicate a mixed fluoride/borate coordination of the rare-earth ions and the absence of nanophase segregation effects.

Metal-organic framework (MOF) glasses are a newly discovered family of melt-quenched glasses. However, so far it is not known whether these glasses exhibit photonic functionalities. Here, we show the discovery of the luminescent behavior of a MOF glass, i.e., the cobalt doped zeolitic imidazolate frameworks-62 (ZIF-62) glass (Zn1-x Cox (Im)1.9 (bIm)0.1, x = 0, 0.1 and 0.5), which was obtained by melt-quenching its corresponding ZIF-62 crystal. The synthesized crystal was precipitated in the form of spherical nano/micro-crystalline structure, which collapses structurally to form laminated glass with ultrahigh glass forming ability and the same short range molecular structure of the parent crystalline MOF. We observed the super-broadband mid-infrared (Mid-IR) luminescence (in the wavelength range of 1.5 µm – 4.8 µm) both in the crystalline and amorphous phases. The observed Mid-IR emission originates from d-d transition of Co2+ ions that is protected by the strong Co-N coordination. The discovery of the luminescent glasses may pave the way towards new photonic applications of bulk MOF glasses, such as Mid-IR lasers.

AIM To investigate whether the use of continuous Pringle maneuver (PM) adversely impacts the outcome of patients with hepatocellular carcinoma (HCC). METHODS From January 1989 to January 2011, 586 HCC patients who underwent curative resection in Peking Union Medical College Hospital were identified from the database. Continuous PM was performed in 290 patients (PM group), including 163 patients with a hepatic inflow occlusion time of

// Wenjun Liao 1 , Huayu Yang 1 , Haifeng Xu 1 , Yanan Wang 2 , Penglei Ge 1 , Jinjun Ren 1 , Wei Xu 1 , Xin Lu 1 , Xinting Sang 1 , Shouxian Zhong 1 , Hongbing Zhang 2 , Yilei Mao 1 1 Department of Liver Surgery, Peking Union Medical College (PUMC) Hospital, PUMC & Chinese Academy of Medical Sciences, Beijing, China 2 State Key Laboratory of Medical Molecular Biology, Department of Physiology, Collaborative Innovation Center for Cancer Medicine, Institute of Basic Medical Sciences and School of Basic Medicine, PUMC & Chinese Academy of Medical Sciences, Beijing, China Correspondence to: Yilei Mao, email: yileimao@126.com Keywords: circulating cell-free DNA, circulating tumor DNA, hepatocellular carcinoma, tumor-associated mutation, MiSeq sequencing Received: December 02, 2015 Accepted: May 02, 2016 Published: May 26, 2016 ABSTRACT Background: Detection of circulating cell-free DNA (cfDNA) has potential clinical value for assessing tumor biology in patients with hepatocellular carcinoma (HCC), yet many traditional assays lack robustness. This study was the first to apply a high-throughput sequencing platform to detect tumor-associated mutations in HCC from circulating tumor-derived DNA (ctDNA) and to evaluate the utility and feasibility of this approach. Methods: Using the MiSeq™ system, plasma and matched tumor DNA samples were analyzed for hotspot mutations in the TERT , CTNNB1 , and TP53 genes that had been verified as the most prevalent mutations in HCC. We compared tumor and plasma data and prospectively investigated the association between significant mutations detected in ctDNA and the patients’ clinical outcomes. Results: In 41 patients, we detected tumor-associated mutations for HCC in 8 (19.5%) plasma samples. Among them, one showed a tumor-associated mutation in ctDNA but not in the tumor tissue which we used to detect. We also found that ctDNA with mutations could be detected more easily in patients who suffered vascular invasion (P=0.041) and predicted a shorter recurrence-free survival time (P