最新刊期
卷 40 ， 期 4 ， 2019
- 摘要：In this work, a facile method was used to prepare 2'-(phenylsulfonyl)spiro[fluorene-9,9'-xanthene] (PSSFX). The thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) curves demonstrate that PSSFX losed 5% weight at decomposition transition temperature of 222℃ and melted at 124℃ with no crystallization phenomena by heating to 160℃. The high triplet energy level(T1, 2.77 eV) of the compound was calculated from phosphorescence spectrum. The separated the highest occupied molecular orbital (HOMO, -5.83 eV) and the lowest unoccupied molecular orbital (LUMO, -1.62 eV) of the compound were calculated by density functional theory(DFT). Cyclic voltammetry measurements were employed in experiment to obtain the HOMO, LUMO, and Eg of -6.33, -2.34, 3.94 eV, respectively. The optical properties of PSSFX were researched in dichloromethane and crystal powder with absorption peaks around 267, 274/351 nm, and emission peaks at about 408, 341 nm, respectively.关键词：steric hindrance;bipolar molecule;facile method;spiro compound;low cost166|176|0更新时间：2020-08-12
- 摘要：Fe3O4 has a wide application prospect in biomedical fields such as cell separation, targeted drugs, magnetic resonance imaging and so on. In this work, Fe3O4 nanoparticles were synthesized by solvothermal method, and the effects of reaction temperature, reaction time and precursor composition on the structure and morphology of Fe3O4 were studied in detail. The reaction time had little effect on the size of the spherical nanoparticles. When the reaction time was 12 h, the diameter of the spheres reached the maximum. When the reaction time was increased, the size of the spheres kept constant. The reaction did not occur when the reaction temperature was 120℃. Face-centered cubic structure Fe3O4 was obtained when the reaction temperature was 160, 200, 240℃. The diameter of Fe3O4 was maximum when the reaction temperature was 200℃. Cube-shaped Fe3O4 was obtained when ethylenediamine was replaced by hydrazine hydrate. In order to improve the chemical stability, biocompatibility and the possibility using Fe3O4 nanoparticles as drug carriers, a layer of SiO2 mesoporous molecular sieve was coated on the surface of Fe3O4 by Stöber method. The effects of ultrasonic and mechanical stirring on the morphology of core-shell structure were investigated. The magnetic properties of the samples before and after SiO2 coating were also studied. The samples were all superparamagnetic before and after coating.关键词：solvothermal method;Fe3O4;SiO2;core-shell243|123|0更新时间：2020-08-12
- 摘要：A series of BaLa1-xLiTeO6:xEu3+ (x=0.1-1) red-emitting phosphors were synthesized by high-temperature solid-state reaction at 1 100℃, and their structure, morphology, spectra and packaging performance were investigated systematically. The maximum doping content of Eu3+ was equal to the optimum one, i. e., x=0.4, beyond which impurities and concentration quenching were observed. The asymmetry ratio of I(5D0→7F2)/I(5D0→7F1) reached 7.31, resulting in high color purity of 99.7% with CIE 1931 chromaticity coordinates of (0.665, 0.334). The fluorescent lifetime and absolute quantum efficiency were measured to be 660.9 μs and 71.4%, respectively. The integrated emission intensity at 100℃ was as high as 84.5% of that at ambient temperature. The thermal activation energy was determined to be 0.434 eV. The prototypical LED based on it enabled to emit bright red light. In conclusion, the phosphor exhibits favorable luminous efficiency, color purity and thermal stability of luminescence, which have potential application in white LEDs.关键词：BaLaLiTeO6:Eu3+;high-temperature solid-state reaction;red-emitting phosphor for LED;luminescence218|287|2更新时间：2020-08-12
- 摘要：In this paper, aminopropylisobutyl polyhedral oligomeric silsesquioxane(POSS-NH2) was decorated with 3-benzylsulfanylthio-carbonylsufanylpropionic acid(BSPA) to prepare a POSS-containing RAFT agent(POSS-BSPA), 4-chloro-7-nitro-2,1,3-benzoxadiazole(NBDCl) as the maternal dye to prepare(2-acryloyloxyethylamino)-7-nitro-2,1,3-benzoxadiazole(NBDAE) fluorescent monomer; a reversible-fragmentation addition(RAFT) copolymerization of N-isopropylacrylamide(NIPAm) and NBDAE were conducted under action of POSS-BSPA and AIBN to synthesize a novel thermosensitive fluorescence hybrid polymer POSS-P(NIPAm-co-NBDAE). The reaction process and structure were investigated by FTIR, 1H NMR and GPC. The fluorescence response behaviors of it to F- and ambient temperature were investigated by photoluminescence(PL) in solution of H2O or THF, and the related mechanism was discussed. The results show that, in aqueous solution, the fluorescence emission of the polymer is influenced greatly by ambient temperature, while it is influenced little in THF solution. Moreover, F- has a relatively slight effect on its fluorescence emission in water, and it can be quenched in THF dramatically.关键词：polyhedral oligomeric silsesquioxane(POSS);reversible-fragmentation addition(RAFT);hybrid;F- detection;N-isopropylacrylamide137|160|0更新时间：2020-08-12
- 摘要：The cubic phase GdF3:Yb3+,Er3+ was synthesized by co-precipitation method and annealed at different temperatures. SEM, XRD, thermogravimetric analysis and photoluminescence (PL) were introduced to investigate the effect of the morphology, crystal structure and upconversion (UC) luminescence properties after being annealed. The results suggest that the translation temperature of NaGdF4:Yb3+,Er3+ crystals from GdF3:Yb3+,Er3+ crystals was 740.15℃. The properties of UC luminescence are stronger comparing with the unsintered samples. Under 980 nm excitation, the UC luminescence intensity firstly increases and then decreases as the rise of temperature, it reaches the maximum value at 800℃ and the intensity ratio of red/green(R/G) rises from 0.09 to 4.55. With the discussion of UC luminescence transition mechanisms, the properties of UC luminescence could be enhanced due to following factors:with the rise of temperature, the particle size increased from 100-300 nm to 5-8 μm because of the particle agglomeration, the improvement of crystallization and a structure change of cubic GdF3:Yb3+,Er3+ to NaGdF4:Yb3+,Er3+ particles.关键词：co-precipitation method;upconversion luminescence;GdF3;rare earth ions174|91|2更新时间：2020-08-12
- 摘要：For preparation of low toxicity and excellent magnetic-fluorescent composite material, carbon quantum dots(CQDs) with high light stability and biocompatibility were selected as fluorescent probe. The CQDs with excellent fluorescence were successfully synthesized by one-step hydrothermal method. Superparamagnetic nanoparticles Fe3O4 were prepared by hydrothermal coprecipitation, which were modified by citric acid(CA) with good biocompatibility.Then Fe3O4/CA was formed and riched of functional hydroxyl and carboxylgroups. Through coupling agent ethylenediamine, the CQDs were connected with Fe3O4/CA for successful preparation of magnetic-fluorescent composite material Fe3O4/CA@CQDs. Fourier transform infrared spectroscopy(FTIR), fluorescence spectrophotometer, vibrating sample magnetometer(VSM), X-ray diffraction(XRD), fluorescence microscope and transmission electron microscopy(TEM) were used for characterization. The results show that the Fe3O4/CA@CQDs possessed core shell structure with an average diameter of 30-40 nm and the saturation magnetic intensity 20.14 A·m2·kg-1. Attributed to the excellent fluorescence properties and magnetic, low cytotoxicity and high biocompatibility, the bifunction composite material is expected to replace traditional magnetic-fluorescent nanocomposites and widely used in biomedical fields.关键词：magnetic;fluorescent;carbon quantum dots;composite material168|53|2更新时间：2020-08-12
- 摘要：In this research, densely aligned TiO2 nanorods are etched into nanotubes by hydrochloric acid, and the growth mechanism is also supposed. During the etching process, the dents appear from the top down and inside out along the growth direction of the nanorod, and finally form the tube structure. Actually, the nanotube with square hollow cross section consists of a mass of surrounded fine nanowires, which will be teared into independent ones at high temperature. When assembled into dye sensitized solar cells(DSSCs), the photoelectrical conversion efficiency of TiO2 nanotubes is much higher than that of nanorods, and the highest value(3.26%) is located at the etching temperature of 140℃. It could be deduced that the increased specific surface area and length shortening of the nanotube play the positive and negative effect on the photoelectrical property, respectively. Furthermore, the calcination effect on the structure and photovoltaic property of TiO2 nanotubes is also carried out. However, the fracture and aggregation of nanotubes could be observed after heating treatment, which therefore increase the difficulty of photo-induced carriers in directional transfer and also reduce the photoelectrical activity.关键词：TiO2 nanotube;etching treatment;growth mechanism;photoelectric property141|112|0更新时间：2020-08-12
- 摘要：In order to enhance the physicochemical properties and processability of rare earth complexes, and to further expand the practical applications in the field of anti-counterfeiting, fluorescent labeling and OLED, in this paper, novel luminescent composite fibers were prepared by electrospinning of PAN solutions containing the europium complex Eu(BPA)3phen. The characterization of the luminescent fibers has been investigated by scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), Fourier infrared spectrometer(FTIR), thermogravimetric analysis(TG-DSC) and fluorescence spectroscopy(PL). The results show that the diameter of composite fibers distributs between 200 nm to 400 nm, and random orientation. Thermogravimetric analysis indicates that the initial decomposition temperature of Eu(BPA)3phen/PAN composite fibers is 330℃, approximately. Furthermore, fluorescence spectra studies revealed that with the increasing of the incorporation of complexes into PAN, the fluorescence intensities were remarkable enhanced and reached its maximum value at 2.5% for Eu(BPA)3phen/PAN fibers. The further intensity decreased with the increasing content of the complexes because of typical emission concentration quenching. The novel luminescent composite nanofibers have potential applications in the field of anti-counterfeiting and OLED.关键词：electrospinning;Eu(BPA)3 phen/PAN fibers;thermal properties;luminescence166|152|0更新时间：2020-08-12
Synthesis and Properties of Materials
-
Monte-Carlo Ray-tracing Simulations of Perovskite Quantum Dots-based Luminescent Solar Concentrators
摘要：The inevitable thermal effects, complex device structure and high manufacturing cost severely hinder the development of the conventional solar concentrators. As a type of novel solar concentrators, luminescent solar concentrator shows numerous potentials to significantly reduce the cost of solar cells and attracts much attentions. Here, the all-inorganic perovskite CsPbBr3 quantum dots are synthesized via a hot-injection approach and then the CsPbBr3-based luminescent solar concentrators are designed and fabricated. According to TEM characterization and spectroscopic measurements, the CsPbBr3 quantum dots exhibit the typical cubic structure, the quantum yield of up to 76.8%, and the PL emission at 512 nm with the FWHM of 22 nm. Further, the optimal quantum dots doping concentration and the average optical collecting efficiency are confirmed by the calculation based on Monte Carlo intelligent optimization algorithm. The optimal average collecting efficiency is 5.4% when CsPbBr3 quantum dots doping concentration is fixed at 2.1×10-5 mol/L. We anticipate this numerical simulation process based on Monte Carlo intelligent optimization algorithm will shed light on the future research for determining the characteristic parameter of luminescent solar concentrators.关键词：photoluminescence;photovoltaic device;Monte Carlo simulation;quantum dots171|196|1更新时间：2020-08-12 - 摘要：The MAPbI(3-x)Brx perovskite solar cell was deposited in one-step solution approach. This study focuses on the influence of MABr on the morphology, optical absorption and photovoltaic performances. The results show that the surface of the deposited CH3NH3PbI(3-x)Brx became rougher and the grain sizes larger with the MABr concentration increasing. UV-Vis-NIR spectra and photoluminescence peak of CH3NH3PbI(3-x)Brx film blue shifted with increasing of the MABr concentration. The MAPbI(3-x)Brx solar cells exhibite open circuit voltage of 1.02 V with power conversion efficiency of 12.68%.关键词：organic-inorganic hybrid;perovskite;morphology;solar cell119|244|0更新时间：2020-08-12
- 摘要：In this work, the electron transport limitations caused by oxide defects was overcome by replacing single layer semiconductor channel with a ZnO/IGZO heterojunction prepared by inkjet printing. It was found that ZnO/IGZO transistor exhibited banded electron transport, and the mobility was increased by about 9 times and 19 times, respectively, to 6.42 cm2/(V·s) compared with single layer IGZO or ZnO TFT. The switch ratio was increased by 2 and 4 orders of magnitude respectively, which can reach 1.8×108. Significant improvement in performance was associated with the two-dimensional electron gas formed between the IGZO and ZnO heterointerfaces due to the large offset of the conduction band.关键词：metal oxide semiconductor;inkjet printing;heterojunction;two-dimensional electron gas177|108|1更新时间：2020-08-12
- 摘要：Compared with their organic counterparts, inorganic charge injection materials possess many tempting properties including high charge carrier mobility, good stability, simple preparation, and low cost, and their applications in optoelectronic devices have been extensively studied. It is reported that cuprous thiocyanate(CuSCN) is utilized as hole injection layer for organometal halide perovskite light-emitting devices. The morphology, crystallite structure, and photo-physics properties of the perovskite films deposited onto CuSCN layer have been studied and further compared with the attributes of the analogs on top of a conducing polymer hole injection layer. The results show that CuSCN has a significant quenching effect on perovskite luminescence. Adding a polymer hole-transporting interlayer between CuSCN and perovskite layer can largely increase the perovskite emission intensity. On this basis, it is reported that the maximum luminous efficiency of the CuSCN-based devices is 11.7 cd/A, nearly 3 times that of the conducting polymer hole injection layer analogs, and the device stability is also improved.关键词：inorganic charge injection layer;CuSCN;luminescence quenching;perovskite light-emitting devices192|308|0更新时间：2020-08-12
Device Fabrication and Physics
- 摘要：The effect of tartrazine on the zein conformation was studied by fluorescence spectroscopy, UV spectroscopy, ATR-FTIR self-deconvolution calculations and 1H NMR spectroscopy, in order to provide a theoretical basis for the modification study of zein and the safe use assessment of tartrazine. The results showed that tartrazine had obvious fluorescence quenching effect on zein, and the quenching mechanism was complicated. Tartrazine can bind to zein, and the molecules were mainly combined by hydrophobic interaction. Using the Stern-Volmer equation and Van't Hoff formula, their binding ratio was calculated to be 1:1 and the binding constant Ka value was larger. By self-deconvolution analysis of Fourier transform infrared spectroscopy, this binding reaction resulted in significant changes in the α-helix structure, β-folding and β-turn angle in the secondary structure of zein. Nuclear magnetic resonance spectroscopy indicated that due to the amphipathic nature of zein, when the solvent was dimethyl sulfoxide, the mixed solution was in a low-polarity environment, the chemical shift shifted slightly to a high magnetic field; when the solvent was heavy water D2O, chemical shifts significantly shift to low magnetic fields, and this effect was independent of the length of reaction time. It was further illustrated that tartrazine can cause changes in the zein conformation in a polar and low polarity environment.关键词：spectral analysis;conformational change;tartrazine;zein;secondary structure174|415|3更新时间：2020-08-12
- 摘要：This paper focused on the research on identifying and classifying for beef varieties of Angus, Limousin and Simmental, by using visible/near-infrared(400~1 000 nm) and near infrared(900~1 700 nm) hyperspectral technologies combined with different characteristic wavelengths selection methods. Meanwhile, the contents of color, tenderness, pH value, moisture, fat and protein were measared. Pretreatment methods were used to process original spectrum respectively according to the characteristics of different spectrum bands; the characteristic wavelengths were extracted by using SPA, IRF and IRF-SPA; then PLS-DA model was applied to identify the different beef varieties under characteristic wavelengths and fullwave bands. Results showed that SNV-IRF-SPA-PLS-DA models achieved the optimal performance in 400~1 000 nm, and the accuracy of the correction set and prediction set was 98.56% and 97.12%, respectively. SG-SPA-PLS-DA models achieved the optimal performance in 900~1 700 nm, and the accuracy of the correction set and prediction set was 94.09% and 96.04%, respectively. There were good effects for beef varieties identification in different hyperspectral bands. The identification accuracy in 400~1 000 nm bands was better than in 900~1 700 nm bands, which explained that the differences of color and texture were more significant than the component contents among the 3 varieties beef. The research indicated that combined hyperspectral technologies with characteristic wavelengths selection methods can obtain a better recognition effect of beef varieties.关键词：hyperspectral imaging technology;characteristic wavelengths;beef breeds;multichannel recognition;interval random frog183|387|1更新时间：2020-08-12
- 摘要：The spatial and temporal resolved optical emission spectrum (OES) has been studied by ICCD for hydrogen and hydrogen/silane mixture gas, in order to deepen the understanding of the plasma enhanced chemical vapor deposition. Plasma clear microcosmic dynamics figures of instantaneous glow discharge have been obtained. In pure H2 plasma, there appear four peaks in one radio frequency cycle. Two of these peaks are formed by electron wave-riding effect, and the other two peaks are caused by the extra electric field which is formed at the instantaneous anode. This phenomenon validates and extends the traditional radio frequency plasma discharge dynamics theory. In addition, from the picture, it can be found that the bulk Ohmic heating mechanism increases with pressure. When introducing the silane into the hydrogen, the four clear peaks change to two clear peaks.关键词：plasma;optical emission spectroscopy;microcosmic dynamics141|203|0更新时间：2020-08-12
- 摘要：In order to qualitatively and quantificationally contract and analyze the influence of soil surface color treated by tung oil and sticky rice juice, the methods of direct observing and color parameter comparison are used. Firstly, soil specimens treated by tung oil and sticky rice juice in different mass ratios are prepared and maintained till the surface color invariable. Secondly, the change of the soil surface color is qualitatively estimated by observing, then the photograph of the specimens is taken under fixed light source to obtain the L*a*b* parameters including the lightness difference, the chroma difference and the total color difference, and the influence caused by the tung oil and sticky rice juice are quantificationally analyzed. The results show that the sticky rice juice could turn the treated soil white and bright slightly while the tung oil could turn the soil black and dark obviously. The treated soil specimen at the mass ratio (tung oil to sticky rice juice to soil) of 5:10:85 has the closest surface color compared to the untreated soil specimen. When the color difference ΔE>5, the difference of the surface color could be observed with naked eyes. The color difference of the treated and untreated soil should be ensured at ΔE<5 in the conservation project of the earthen sites. When using tung oil and sticky rice juice to improve the soils, the mass ratio should be controlled at 5:10:85 to guarantee the best consistency of the surface color.关键词：earthen site conservation;tung oil;sticky rice juice;color difference;L*a*b* color system134|162|0更新时间：2020-08-12
- 摘要：A novel derivative L based on tetraphenylethylene-rhodamine was synthesized. FT-IR, NMR, UV-Vis and solution fluorescence and cyclic voltammetry electrochemical analysis were used to study the structure, optical properties, recognition ability of compound L to metal ions and electrochemical properties. The experimental results showed that compound L possessed a significant aggregation-induced emission(AIE) characteristic in different V(EtOH):V(H2O) mixed solvents. When 10 equiv. of Fe3+ was added to the solution containing probe, the solution of compound L in EtOH/H2O(V:V, 1:1, Tris-HCl, pH=7.0) changed the color from colorless to red. Except that the addition of Al3+ or Cr3+ slightly changed the solution color to reddish, the addition of other metal ions did not induce significant color changes. The fluorescence spectra showed that when fluorescence emission wavelength at 508 nm was quenched with a quenching ratio of 87.5% and the detection limit of Fe3+ was as low as 4.56×10-6 mol/L. Interestingly, the fluorescence intensity at 582 nm increased with the addition of Fe3+, which was increased by 49.6 times with the detection limit of Fe3+ was as low as 7.4×10-7 mol/L, which achieved the "turn-off" and "turn-on" visual detection of Fe3+ at the maximum fluorescence emission wavelengths of 508 nm and 582 nm, respectively. Thus, the probe L is a highly sensitive, specific, and visible fluorescent probe for the detection of Fe3+. The mechanisms have been supported by reversibility of the Job's plot, UV-vis and fluorescence titrations, 1H NMR spectroscopic studies and SEM images. The complexing ratio of probe L with Fe3+ was determined to be 2:1. The test was conducted in neutral aqueous solutions, which indicated that the probe L could be applicable to the research on the biological and environmental applications associated with Fe3+. Cyclic voltammetry electrochemical analysis was used to study their electrochemical properties, the results showed that L had good hole transporting ability and good electron transporting capability. L can be used as a optoelectronic material.关键词：tetraphenylethyene;rhodamine B;naked-eye recognition;“turn-off”and “turn-on”Fe3+ fluorescence probe167|174|1更新时间：2020-08-12
Luminescence Applications and Interdisciplinary Fields
- Address：No.3888 Dong Nanhu Road, Changchun, Jilin, China Postal code：130033
- Tel：0431-86176862 Email：fgxbt@126.com
- Technical support is provided by Beijing Founder electronics co., LTD 吉ICP备11002662号-17
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0