Search

We report magneto-dielectric properties of partially B-site ordered monoclinic ${\mathrm{Tb}}_{2}\mathrm{CoMn}{\mathrm{O}}_{6}$ double perovskite thin film epitaxially grown on $\mathrm{Nb}:\mathrm{SrTi}{\mathrm{O}}_{3}$(100) substrates by metalorganic aerosol deposition technique. Transmission electron microscopy and electron energy loss spectroscopy mapping shows the presence and distribution of both $\mathrm{C}{\mathrm{o}}^{2+}$ and $\mathrm{C}{\mathrm{o}}^{3+}$ ions in the film, evidencing a partial $B$-site disorder, which was further confirmed by the observation of reduced saturation magnetization at low temperatures. The ferromagnetic Curie temperature, ${T}_{C}=110\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, is slightly higher as compared to the bulk value (100 K) probably due to an in plane epitaxy tensile strain. Temperature dependent dielectric study reveals an unexpected high temperature dipolar relaxor-glass-like transition at a temperature ${T}^{*}\ensuremath{\sim}190\phantom{\rule{0.16em}{0ex}}\mathrm{K}g{T}_{\mathrm{C}}$, which depends on the applied frequency and indicates a superparaelectric behavior. Two different dielectric relaxation peaks have been observed; they merge at ${T}^{*}$ where likely a coupling to the disorder-induced short range charge-spin correlations results in a 4% magneto-dielectric coupling.

The constituents of essential oils isolated by hydro-distillation of the aerial parts of six Ocimum species were examined by Gas Chromatography-Mass Spectrometry (GC-MS). Highest percentage of essential oils (dry weight basis) was found in O. kilimandscharium (2.47 %) and lowest in O. tenuiflorum green type (0.65 %). On fresh weight basis, the percentage of essential oils was highest in O. b. var. glabratum (0.76 %) and lowest in O. viride (0.001 %). A total of eight major components were identified. The oil of O. b. var. basilicum contained, as main components, methyl chavicol and linalool. Major compound in O. b. var. pilosum was methyl chavicol; in O.b. var. glabratum, O. b. var. thyrsiflora and O. b. var. difforme was linalool; β cedrene and linalool in O. b. var. purpurascens; methyl chavicol in O. citriodorum; camphor and 1,8-cineole in O. kilimandascharium; β bisabolene and 1,8-cineole in O. viride; eugenol in O. tenuiflorum, and eugenol and methyl eugenol in O. gratissimum.

Since time immemorial, the natives were growing and maintaining plant diversity in the vicinity of dwelling places which is popularly known as Home Garden. The present study was conducted to assess role of home garden for in-situ conservation of plant diversity in Dhari Block, district Nainital, Uttarakhand with the major aim of understanding the plant diversity available especially with respect to the home gardens and role of vice-versa in their day to day life. With the help of questionnaire and survey, the information was collected from six villages i.e., Chaukuta, Dhanachuli, Gajar, Kasiyalekh, Podiyal and Pokhrar. Information regarding the occurrence of plant species, their local names, parts used and formulation through interviews and discussions held with elderly persons of rural communities were recorded. The study documented 93 plant species belonging to 79 genera and 51 families ranging from forestry to horticulture and agriculture including ethno-medicinal plants as grown in the home gardens and these plant species were used for multiple purposes i.e., Cereals, Fire woods, Fodders, Fruits, Leafy vegetables, Ornamentals, Pseudo-cereals, Spices, Vegetables and other cultural significance. These observations indicated that home garden play a important role in food security and in-situ conservation of agri-horticultural plants.

Uttarakhand is a store house of plant genetic resources of several crop groups including ornamentals and seasonal flowering plant species. A wide range of seasonal flowering plants are being grown in the region because of its various and favourable agro-geo climatic zones. Ornamental plant enhances aesthetic value of our environment. There are 8 developmental blocks and 1082 villages in district Nainital of Uttarakhand. Nainital district, is a part of Kumaun region of Uttarakhand. It lies between 29?0.1' to 29?36' 21'' N latitude and 78?50' 53'' to 80?06' E longitude. More than 7.62 lakh population reside in 4064 km2 of geographical area of district Nainital. The district falls under sub-tropical to temperate zones. During the course of field survey (2013-2015), we came across wide range of seasonal flowering plants mostly belong to exotic origin being grown in the home gardens of natives of the region situated in different agro-ecological niches. The present study highlighted a total of 150 seasonal flowering plants with 120 genera belonging to 50 families. These were arranged alphabetically with botanical names followed by vernacular and trade name, family, origin or native place, nature, season with appropriate remarks of variation in shape, size and colour, method of propagation with economic status.

Sweet basil is an incredible herb, used both as a classic culinary and ornamental herb of Home Gardens. The genus Ocimum contains approximately 65 species of herbs and shrubs originated in tropical Asia. It has a strong medicinal use and it is very high in vitamins and minerals. The present study holds 6 varieties of Ocimum basilicum L. consisting of 29 accessions were procured from National Gene Bank, New Delhi. These accessions were grown in the Kharif seasons of 2014-15 at ICAR-NBPGR Regional Station, Bhowali, Nainital Uttarakhand for analysing of their quantitative and qualitative or phenotypic characters for identification of superior genotypes. The comparative study of Ocimum spp. was examined to assess the variability of qualitative and quantitative morphological characters using standardized description present among 30 accessions of 6 varieties of Ocimum basilicum L. (Sweet Basil).

Multiferroics where at least two primary ferroic orders are present and coupled in a single system constitute an important class of materials. They attracted special consideration as they present both intriguing fundamental physics problems and technological importance for potential multifunctional devices. Here, we present the evidence of multiferroicity and magnetoelectric (ME) coupling in alpha-Mn2O3; a unique binary perovskite. Corresponding to the antiferromagnetic (AFM) ordering around 80K, a clear frequency independent transition is observed in the dielectric permittivity. We showed that electric polarization emerges near AFM regime that can be modulated with magnetic field. The detailed structural analysis using synchrotron radiation X-ray diffraction demonstrates the increase in structural distortion with decreasing temperature, as well as changes in the unit cell parameters and bond lengths across the ferroelectric and magnetic ordering temperatures. This observation of multiferroicity and magnetoelastic coupling in alpha-Mn2O3 provides insights for the exploration of ME coupling in related materials.

In traditional systems of medicine along with holistic approach, different parts of basil (Ocimum spp.) have been prescribed for the treatment of various ailments. Morphological and anatomical characters play a vital role in plant based crude drug identification and standardization. This study aimed to characterize the morphological and anatomical structure of four different species of Ocimum such as Ocimum basilicum var thyrsiflora L. commonly named as Thai basil; Ocimum tenuiflorum L. as Holy or sacred basil; Ocimum gratissimum L. as Shrubby basil or Clove basil and Ocimum viride Willd. as Temple basil or Fever plant of Sierra Leone. This study is useful to correct identification judging the authencity of the plant and to differentiate these species from each other’s while undertaking pharmacognostical characterization and evaluation. Key words: Basil, Anatomical, Morphological, Medicinal crude drugs.