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71.
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
72.
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
73.
The protective action and the influence on physical ripening for silver halides crystals of a number of water soluble polymers of acrylamide and N-mono and bis-methyl substitutes are investigated. Viscosity and solubility of polymers are considered in order to explain the experimental results obtained. 相似文献
74.
The multiband iron-based superconductors have layered structure with a phase diagram characterized by a complex interplay of charge, spin and lattice excitations, with nanoscale atomic structure playing a key role in their fundamental electronic properties. In this paper, we briefly review nanoscale structure and atomic disorder in iron-based chalcogenide superconductors. We focus on the Fe(Se,S)1−xTex (11-type) and K0.8Fe1.6Se2 (122-type) systems, discussing their local structure obtained by extended x-ray absorption fine structure. Local structure studies on the Fe(Se,S)1−xTex system reveal clear nanoscale phase separation characterized by coexisting components of different atomic configurations, similar to the case of random alloys. In fact, the Fe–Se/S and Fe–Te distances in the ternary Fe(Se,S)1−xTex are found to be closer to the respective distances in the binary FeSe/FeS and FeTe systems, showing significant divergence of the local structure from the average one. The observed features are characteristic of ternary random alloys, indicating breaking of the local symmetry in these materials. On the other hand, K0.8Fe1.6Se2 is known for phase separation in an iron-vacancy ordered phase and an in-plane compressed lattice phase. The local structure of these 122-type chalcogenides shows that this system is characterized by a large local disorder. Indeed, the experiments suggest a nanoscale glassy phase in K0.8Fe1.6Se2, with the superconductivity being similar to the granular materials. While the 11-type structure has no spacer layer, the 122-type structure contains intercalated atoms unlike the 1111-type REFeAsO (RE = rare earth) oxypnictides, having well-defined REO spacer layers. It is clear that the interlayer atomic correlations in these iron-based superconducting structures play an important role in structural stability as well as superconductivity and magnetism. 相似文献
75.
76.
多年来,整体技术已经成功地从概念阶段发展到表征良好且可重复的商用阶段。不同的整体柱化学材料,包括阴离子交换剂、阳离子交换剂和在ProSwift线性整体柱的反相功能基团,均可用于多种蛋白质的分离。与更大尺寸的色谱柱相比,1-mm内径的色谱柱在灵敏度提高和使用方便二者间达到了很好的协调。由于背压较小,这些整体柱可以在高动力学流速下运行,从而可以在标准的分析型色谱仪器上使用,而不需要微柱或者毛细管柱高效液相色谱系统。 相似文献
77.
Fire Technology - The tendency of self-ignition of coal is the root cause of underground coal fires (UCFs). A parametric study is carried out on a lab-scale experimental setup developed based on... 相似文献
78.
Dikshant Saini Behrouz Shafei 《The Structural Design of Tall and Special Buildings》2023,32(11-12):e2036
Concrete-filled steel tubes (CFSTs) have received growing attention, owing to their rapid construction, reduced labor requirement, and reasonable material cost. While in service, the CFSTs can be subjected to unexpected impact loads, originating from vehicle and vessel collision, as well as water- and wind-borne debris impact. Such extreme loading events often cause a partial or complete failure of conventional CFSTs, risking the safety and performance of the entire structural systems that rely on them. To address this issue, the current study explores how two advanced composite materials, including ultra-high-performance fiber-reinforced concrete (UHPFRC) and carbon fiber-reinforced polymer (CFRP), can be utilized to provide superior mechanical properties and minimize the vulnerability of CFSTs to impact loads. The composite materials under consideration are appropriate for both new and existing structures, in which normal-strength concrete can be replaced with UHPFRC, while CFRP sheets can further strengthen the CFSTs. For obtaining in-depth insights, a computational framework validated with the experimental tests was developed in the current study. Using a set of representative impact scenarios, various response measures, such as internal forces and deflections, as well as the energy absorbed by the CFSTs, were recorded during impact simulations. The investigations were then further extended to capture the influence of the main design parameters related to concrete, CFRP, and steel tube. From the conducted investigations, an energy absorption index was introduced, as a measure to evaluate the performance of CFSTs under impact loads. 相似文献
79.
Vandita Kakkar Indu Pal Kaur Amrit Pal Kaur Komal Saini Kamalinder K. Singh 《Drug development and industrial pharmacy》2018,44(10):1701-1712
Tetrahydrocurcumin (THC) also referred to as ‘white curcumin’, is a stable colorless hydrogenated product of curcumin with superior antioxidant and anti-inflammatory properties. The present study is an attempt to elevate the topical bioavailability of THC, post-incorporation into a nano-carrier system with its final dosage as a hydrogel. Lipid nanoparticles of THC (THC-SLNs) prepared by microemulsification technique were ellipsoidal in shape (revealed in transmission electron microscopy) with a mean particle size of 96.6?nm and zeta potential of ?22?mV. Total drug content and entrapment efficiency of THC-SLNs was 94.51%?±?2.15% and 69.56%?±?1.35%, respectively. Differential scanning calorimetry and X-ray diffraction studies confirmed the formation of THC-SLNs. In vitro drug release studies showed the drug release from THC-SLNs gel to follow Higuchi’s equation revealing a Fickian diffusion. Ex vivo permeation studies indicated a 17 times (approximately) higher skin permeation of THC-SLNs gel as compared with the free THC gel. Skin irritation, occlusion, and stability studies indicated the formulation to be nonirritating, and stable with a desired occlusivity. Pharmacodynamic evaluation in an excision wound mice model clearly revealed the enhanced anti-inflammatory activity of THC-SLNs gel and was further confirmed using biochemical and histopathological studies. It is noteworthy to report here that THC-SLNs gel showed significantly better (p?≤?0.001) activity than free THC in gel. As inflammation is innate to all the skin disorders, the developed product opens up new therapeutic avenues for several skin diseases. To the best of our knowledge, this is the first paper elaborating the therapeutic usefulness of white curcumin-loaded lipidic nanoparticles for skin inflammation. 相似文献
80.
G. Campi T. Proffen X. Qiu E. S. Bozin S. J. L. Billinge S. Agrestini N. L. Saini A. Bianconi 《Journal of Superconductivity and Novel Magnetism》2007,20(7-8):505-510
We have studied temperature evolution of the local as well as the average crystal structure of MgB2 and Mg0.5Al0.5B2 using real-space atomic pair distribution function (PDF) measured by high resolution neutron powder diffraction in a wide
temperature range of T=10–600 K. The mean square relative displacements (MSRD) of atomic B–B, B–Mg (B–Al) pairs are compared with mean-square displacements
(MSD) to calculate atomic correlations. In spite of the enhanced atomic disorder in Mg0.5Al0.5B2, where the boron–boron, and boron–magnesium pair motions are found to be small, we find that the same atomic correlations
in MgB2 assume even slightly lower values and remain nearly constant in a wide temperature range of 0–600 K. This anomalous behavior
and its physical interpretation provoke new questions on our understanding to the local lattice dynamics in this material. 相似文献