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101.
The market for minimally processed ready-to-eat (RTE) baby-leaf vegetables (BLVs) has been rapidly growing and offering to consumers convenient and appealing products, rich in health beneficial bioactive compounds. These vegetables are harvested at a very early stage of maturation and prepared with minimal processing methods such as cutting, washing, rinsing, and packaging with the modified atmosphere of O2, CO2, and relative humidity (RH). Maintenance of microbial safety, color, texture, aroma, and nutrients are the major problems associated with commercial production and marketing of BLVs. This review discusses the theoretical aspects and recent developments in the maintenance of nutritional quality and microbial safety during production, processing, sanitization, packaging, and storage of BLVs. The varietal improvements in BLVs for wider adaptability and disease resistance are also discussed. Additionally, future research challenges in these contexts are identified. 相似文献
102.
S. Anoop Kumar Avanish Pratap Singh Parveen Saini Fehmeeda Khatoon S. K. Dhawan 《Journal of Materials Science》2012,47(5):2461-2471
This article reports the synthesis, charge transport studies, and microwave shielding properties of polyaniline–Ti-doped γ-Fe2O3 nanocomposite. The composite has been prepared by the in situ chemical oxidative polymerization using dodecylbenzenzesulfonic
acid as a dopant. These resulting polymer composites have been found thermally stability up to 260 °C with magnetization value
of ~10 emu/g. The temperature dependence of electrical conductivity reveals the applicability of Mott’s 3D-VRH model. The
composites has shown the shielding effectiveness of 35.64–45.20 dB (>99.99% attenuation) in 12.4–18 GHz (Ku-Band) frequency
range. The enhancement of SE has been due to combination of dielectric and magnetic losses leading to decrease in skin depth
increase in total (σT) conductivity and better matching of input impedance. 相似文献
103.
104.
105.
D. Di Gioacchino A. Marcelli A. Puri A. Iadecola N. L. Saini A. Bianconi 《Journal of Superconductivity and Novel Magnetism》2012,25(5):1289-1292
In this letter, the electromagnetic response of the NdFeAsO1?0.14F0.14 (T c =49?K) superconductor system, characterized by FeAs and NdO alternating layers, has been compared with that of FeSe0.88. We have studied the flux dynamics of these two systems by means of ac multi-harmonic magnetic susceptibility. The analysis shows that although characterized by larger thermal fluctuations due to its higher T c , NdFeAsO1?0.14F0.14 exhibits a stronger pinning force relative to FeSe0.88. The further Irreversibility Line (IL) analysis also points out that both superconductors have a 3D flux pinning behavior. We associate the stronger pinning force in the NdFeAsO1?0.14F0.14 structure to the presence of the extra NdO layer. Different pinning contributions can be associated to the structural stress associated to FeAs superconducting layers and/or to the Nd3+ ions magnetic moment (????3.6???B) contribution on the flux cores. We will also show that these pinning are over imposed to a weak collective contribution due to the dopant F atoms. 相似文献
106.
T. Mizokawa T. Sudayama Y. Wakisaka D. Ootsuki M. Imaizumi T. Noji Y. Koike S. Pyon K. Kudo M. Nohara H. Anzai M. Arita H. Namatame M. Taniguchi N. L. Saini 《Journal of Superconductivity and Novel Magnetism》2012,25(5):1343-1346
We have studied the electronic structure of FeSe1?x Te x and Ir1?x Pt x Te2 using photoemission spectroscopy. For FeSe1?x Te x , angle-resolved photoemission results indicate that the Fe 3d yz/zx orbital degeneracy at ?? point and orbitally induced Peierls effect in the tetragonal lattice play important roles for the superconductivity. It is suggested that the Jahn-Teller instability of the yz/zx states couples with local lattice distortion derived from the Te substitution for Se and provides an inhomogeneous electronic state. Photoemission results of IrTe2 with triangular lattice are also consistent with the orbitally induced Peierls scenario. The Pt substitution for Ir suppresses the static band Jahn?CTeller effect and induces an inhomogeneous electronic state in which orbital (or bond or nematic) fluctuations may help superconductivity through the Peierls effect. 相似文献
107.
To study the detailed characteristics of a nano-periodic Josephson junction array in a Bi2Sr2Ca2Cu3O10+δ
(Bi-2223) single crystal whisker without shunted grain boundaries, we fabricate a submicron stack with an area of 0.5 μm×0.5 μm
and height of approximately 200 nm using a focused ion beam (FIB) etching technique. The stack has several hundreds of elementary
Josephson junctions along the c-axis. We fabricate the stack by rotation and tilt of the sample stage in the FIB. The current–voltage (I–V) characteristics give a well-defined superconducting gap (V
g) and we notice suppression of the critical current in submicron junction with respect to big sized junction. We believe that
the suppression of critical current in submicron junction is due to the normal resistance of the junction which belongs to
the quantum resistance range. 相似文献
108.
Debapriya Mohanty Rajashree Jena Ritesh Pattnaik Swati Mohapatra Manish Ranjan Saini 《International Journal of Food Properties》2016,19(4):837-846
In recent decades, bioactive peptides have attracted increasing interest as health promoting functional foods. A variety of naturally formed bioactive peptides have been found in fermented dairy products such as yogurt, sour milk, and cheese. Initially these peptides are inactive within the sequence of the parent protein molecule and can be generated by gastrointestinal digestion of milk, fermentation of milk with proteolytic starter cultures, and/or hydrolysis by proteolytic enzymes. Milk derived peptides exert a number of health beneficial activities, even upon oral administration. Bioactive peptides have a great impact on major body systems including the digestive, nervous, endocrine, cardiovascular, diabetes type II, obesity, and immune systems. Antimicrobial peptides are also an important ingredient of innate immunity, especially at mucosal surfaces such as lungs and small intestine that are constantly exposed to a range of potential pathogens. Therefore, it plays an important role in boosting natural immune protection by reducing the risk of chronic diseases. Bioactive peptides are considered as potent drugs with well-defined pharmacological residues and also used to formulate health-enhancing nutraceuticals. 相似文献
109.
Sandeep Nath Tripathi Parveen Saini Deeksha Gupta Veena Choudhary 《Journal of Materials Science》2013,48(18):6223-6232
We report the effect of filler incorporation techniques on the electrical and mechanical properties of reduced graphene oxide (RGO)-filled poly(methyl methacrylate) (PMMA) nanocomposites. Composites were prepared by three different techniques, viz. in situ polymerisation of MMA monomer in presence of RGO, bulk polymerization of MMA in presence of PMMA beads/RGO and by in situ polymerization of MMA in presence of RGO followed by sheet casting. In particular, the effect of incorporation of varying amounts (i.e. ranging from 0.1 to 2 % w/w) of RGO on the electrical, thermal, morphological and mechanical properties of PMMA was investigated. The electrical conductivity was found to be critically dependent on the amount of RGO as well as on the method of its incorporation. The electrical conductivity of 2 wt% RGO-loaded PMMA composite was increased by factor of 107, when composites were prepared by in situ polymerization of MMA in the presence of RGO and PMMA beads, whereas, 108 times increase in conductivity was observed at the same RGO content when composites were prepared by casting method. FTIR and Raman spectra suggested the presence of chemical interactions between RGO and PMMA matrix, whereas XRD patterns, SEM and HRTEM studies show that among three methods, the sheet-casting method gives better exfoliation and dispersion of RGO sheets within PMMA matrix. The superior thermal, mechanical and electrical properties of composites prepared by sheet-casting method provided a facile and logical route towards ultimate target of utilizing maximum fraction of intrinsic properties of graphene sheets. 相似文献
110.
Processable copolymers of aniline with 2-alkylanilines were prepared by in situ chemical oxidative polymerization route. Formation of copolymers was confirmed by X-ray diffractometer (XRD), UV–Vis, and solubility measurements. XRD revealed that copolymerization leads to increase in inter-chain spacing and reduction of doping levels. UV–vis results showed that incorporation of substituted anilines in copolymeric backbone leads to decrease in conjugation, the extent of which is directly related to size of alkyl substituent. The electrical conductivities of these copolymers were slightly less than pure polyaniline, but noticeable improvement in the solution processability was observed. In addition, these copolymers also provided shielding against electromagnetic interference (EMI) with ~99 % attenuation of incident energy. Among various copolymers, 95:5 copolymer of aniline with 2-isopropyl aniline (CP95Ip) gave best performance in terms of electrical conductivity (12.8 S/cm), solubility (4.9 g/L in N-methyl pyrrolidone), and EMI shielding effectiveness (?23.2 dB) values. 相似文献