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Rice crop in coastal areas is very often subjected to major abiotic stresses like submergence, lodging of the crop caused by heavy rains or cyclones and salinity. Identification of genotypes tolerance to multiple abiotic stresses is needed to sustain under climate changed conditions. NILs of Pushyami (MTU 2336-62-25-38-16, MTU 2336-70-46-25-44) with Sub1 locus expressed tolerance to flash floods and also stagnant flooding and lodging resistance. NILs of Amara (MTU 2244-119-59- 63-40, MTU 2244-119-83-65, MTU 2244-39-10-44-1) having sub1 expressed tolerance to stagnant flooding, lodging resistance and moderate tolerance to salinity along with targeted trait of flash flood tolerance. NILs of Swarna (MTU 2546A- 13-1-6-1, MTU 2546A-12-18-1, MTU 2546A-34-1-9-1) expressed moderate tolerance to anaerobic germination along with its targeted lodging related traits. NILs of Cottondora sannalu (DST 8-162-4, DST 9-157-7, DST 8-4-4) expressed lodging, flash flood, anaerobic germination along with targeted trait of seedling stage salinity tolerance. The results showed that NILs possessing multiple abiotic stress tolerance would sustain even under climate changed conditions.

Alkali oxide modified borosilicate glasses, doped with Eu3+ ions with the chemical composition of 74.5 B2O3+10SiO2+5 MgO+R+0.5 Eu2O3 [where R=10 (LiO2/Na2O/K2O) for series A and R=5 (Li2O+Na2O/Li2O+K2O/K2O+Na2O) for series B] have been prepared using the conventional melt quenching technique. Moreover, the spectroscopic properties of the prepared glasses have been studied by Fourier transform infrared spectroscopy (FTIR), optical absorption analysis, photoluminescence excitation (PLE) and Photoluminescence (PL) analysis. The red emission corresponding to the 5D0 →7F2 (614 nm) transition is registered under the excitation of 396 nm of the Eu3+ ions for all the prepared glasses. Based on the PLE and PL measurements, several spectroscopic properties were calculated, such as the fluorescence intensity ratio (R), Judd-Ofelt (J-O) intensity parameter (Ω2), peak emission wavelength ( λ P ), effective line width ( ∆ λ P ), radiative transition probabilities ( A R ), stimulated emission cross-section ( σ e ), experimental branching ratios ( β m ) and gain bandwidth parameters ( σ e × ∆ λ P ). The high values of σ e , β m A R for the 5D0→7F2 transition for our structures indicate that it may be a potential candidate for the red color center in display devices as well as a red emission laser with a wavelength of 614 nm.

The optical properties of borotellurite glasses doped with Nd3+ ions or codoped with Er3+–Yb3+ ions are investigated, in order to evaluate the potential application of these types of glass in laser systems and amplifier materials. The Judd–Ofelt (JO) model is used to determine the absorption intensities of both types of glass so as to establish the J–O intensity parameters ( Ω λ ). The J–O intensity parameters are then used to determine the various radiative parameters viz., the radiative transition probabilities ( A R ), branching ratios ( β R ), stimulated emission cross-sections ( σ e ), full width half maxima ( Δ λ p ) and radiative lifetimes ( τ R ) of both types of glass, which are also compared to the equivalent parameters for other host glasses. It has been shown that Yb3+ acts as an Er3+ sensitizer and contributes largely to the improvement of the spectroscopic properties of the glasses that is codoped with Er3+–Yb3+. The obtained values of A R , β R , τ R , σ e and Δ λ p for the Nd3+- and Er3+-doped glass show that both the 4F3/2 → 4I11/2 transition at 1.06 μm in the Nd3+ case and the 4I13/2 → 4I15/2 transition at 1.56 μm for the Er3+ case exhibit better NIR luminescence at a level suitable for photonic device applications. The potential of the glasses examined in this study, due to their promising gain media, is also discussed in terms of the development of solid state NIR lasers and optical amplification for telecommunication applications.

Enhanced red luminescence in LnVO 4 : Bi 3+ , Eu 3+ @ SiO 2 phosphors has been improved mainly in three stages by investigating the effects of: (i) host composition (Gd, Y and Gd/Y), (ii) co-doping Bi 3+ as a sensitizer and finally (iii) SiO 2 shell coating. XRD data revealed that the produced phosphors possess crystalline, pure phase with tetragonal structure. Silica coating on phosphor particles have been characterized by SEM/EDAX, TEM, PL and with the presence Si–O–Si, Si–O vibrational modes from the FT-IR spectra. Absorption band edges due to VO 4 3− , shifted to higher wavelength with Bi-concentration, owing to the presence of Bi–O bond in addition to V–O. The emission intensities of 5 D 0 → 7 F 2 transition are stronger than 5 D 0 → 7 F 1 ; indicating the lower inversion symmetry near Eu 3+ , ions. Red emission intensity due to the efficient energy transfer from VO 4 3− to Eu 3+ via Bi 3+ ions in Y 0.949 VO 4 : Bi 3+ 0.001 , Eu 3+ 0.05 phosphor was improved significantly, i.e. 1.6 times compared to Y 0.95 VO 4 : Eu 3+ 0.05 . This was further enhanced 2.25 times by SiO 2 shell coating. Thus, Y 0.949 VO 4 : Bi 3+ 0.001 , Eu 3+ 0.05 @ SiO 2 are suggested to be a promising red phosphor for application in display devices or lighting.

This paper reports on the preparation and spectral properties of europium (Eu3+) and terbium (Tb3+) ions doped cadmium lead boro tellurite (CLBT) glasses. For reference glasses, physical properties have been evaluated. From the [measurements of X-ray diffraction (XRD), glass amorphous nature of these [glasses has been studied. From the emission spectra of Eu3+: CLBT glasses, five [transitions (5D0 → 7F0, 7F1, 7F2, 7F3 and 7F4) at 579, 591, 613, 652 and 701 nm are observed with λexci = 392 nm (7F0 → 5L6) and in the case of Tb3+: CLBT glasses, four emission transitions 5D4 → (7F6, 7F5, 7F4 and 7F3) are observed at 489, 543, 584 and 621nm respectively monitered with λexci = 376 nm (7F6 → 5G6).

A new series of Eu3+ ions-activated calcium gadolinium tungstate [Ca2Gd2W3O14] phosphors were synthesized by conventional solid-state reaction method. The X-ray diffraction patterns of the powder samples indicate that the Eu3+: Ca2Gd2W3O14 phosphors are of tetragonal structure. The prepared phosphors were well characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL), and mechanoluminescence (ML) spectra. PL spectra of Eu3+: Ca2Gd2W3O14 powder phosphors have shown strong red emission at 615 nm (5D0 → 7F2) with an excitation wavelength λexci = 392 nm (7F0 → 5L6). The energy transfer from tungstate groups to europium ions has also reported. Mechanoluminescence studies of Eu3+: Ca2Gd2W3O14 phosphors have also been explained systematically.

Novel green nanophosphors Ca2Gd2W3O14: Tb3+ were synthesized by solid state reaction method. From the X-ray diffraction profiles it is observed that Tb3+: Ca2Gd2W3O14 phosphors were crystallized in the form of tetragonal structure. The scanning electron microscopy (SEM) image shows that the particle size is at around 300 nm. In addition to these the prepared powder phosphors were also examined by the energy dispersive X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL) and mechanoluminescence (ML) spectra. Emission spectra of Tb3+: Ca2Gd2W3O14 nanophosphors have shown bright green emission at 545 nm (5D4 → 7F5) with an excitation wavelength λexci = 374 nm (7F6 → 5G6). ML spectra shows the radiation effect on the Ca2Gd2W3O14: Tb3+ nanophosphors and from that it was observed that these phosphors are very less sensitive for lower exposure.

This article reports on the optical absorption and NIR emission properties of Nd3+ ions doped CdO–Bi2O3–B2O3 (CdBiB) glasses. Judd–Ofelt theory has been applied to calculate the oscillatory strengths of the transitions in the absorption spectra and also the intensity parameters Ωλ (λ = 2, 4, and 6). These results were then used to compute the radiative properties of emission transitions of Nd3+:CdBiB glasses. From the NIR emission spectra of Nd3+:CdBiB glasses, three NIR emission bands are observed at 900, 1069, and 1338 nm and assigned to the transitions (4F3/2 → 4I9/2), (4F3/2 → 4I11/2), and (4F3/2 → 4I13/2), respectively. The concentration quenching phenomenon has also been explained. The stimulated emission cross-section and FWHM values were calculated for all the Nd3+:CdBiB glasses.

Rare-earth ions (Eu3+, Tb3+) activated magnesium calcium bismuth titanate [(MgCa)2Bi4Ti5O20] ceramics were prepared by conventional solid state reaction method for their structural and luminescence properties. By using XRD patterns, the structural properties of ceramic powders have been analyzed. Emission spectrum of Eu3+:(MgCa)2Bi4Ti5O20 ceramic powder has shown strong red emission at 615 nm (5D0 → 7F2) with an excitation wavelength λexci = 393 nm and Tb3+:(MgCa)2Bi4Ti5O20 ceramic powder has shown green emission at 542 nm (5D4 → 7F5) with an excitation wavelength λexci = 376 nm. In addition, from the measurements of scanning electron microscopy (SEM), Fourier transform-infrared (FTIR) and energy dispersive X-ray analysis (EDAX) results the morphology, structure and elemental analysis of these powder ceramics have been studied.

We report here on the development and spectral analysis of Cu2+ (0.5 mol%) and Mn2+ (0.5 mol%) ions doped in two new series of glasses. The visible absorption spectra of Cu2+ and Mn2+ glasses have shown broad absorption bands at 820 nm and 495 nm, respectively. For Cu2+ BFP glasses, excitation at 380 nm, a blue emission at 441 nm and also a weak emission at 418 nm ions have been observed. For Mn2+ ions doped BFP glasses, excitation at 410 nm and a red shift at 605 nm emission have been observed.

Electron Spin Resonance Studies of Gd3+ Ions in Calcium Tungsten and Calcium Tungsten Copper Phosphors: A Comparative Study

Characterization of Boro-fluoro-phosphate Glasses

An alternative and efficient telescopic approach to the synthesis of 3-(4-chloro butyl)-1H-indole -5-carbonitrile(2), a key intermediate in the synthesis of Vilazodone hydrochloride (1), is described.

An alternative and efficient telescopic approach to the synthesis of 3-(4-chloro butyl)-1H-indole -5-carbonitrile (2), a key intermediate in the synthesis of vilazodone hydrochloride (1), is described.

Globalization and internationalization are not strange things to agriculture. Since mid-seventies farmers’ incomes have been heavily dependent on their success in selling products in regional, national and international markets. More recently, the development of agreements such as WTO and NAFTA have been the focal point of much of the globalization discussion, with the emphasis on broader access to world markets, expanding exports of agricultural commodities and particularly, further processed agricultural and food products.