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51.
Sukhvinder Pal Singh Zora Singh 《International Journal of Food Science & Technology》2013,48(2):363-374
Our objective was to compare the effects of controlled atmosphere (CA) and modified atmosphere packaging (MAP) on fruit quality, chilling injury (CI) and pro‐ and antioxidative systems in ‘Blackamber’ Japanese plums. Matured fruit were stored for 5 and 8 weeks at 0–1 °C in normal air, CA‐1 (1% O2 + 3% CO2), CA‐2 (2.5% O2 + 3% CO2) and MAP (~10% O2 and 3.8% CO2). CA was more effective than MAP in retention of flesh firmness and titratable acidity during cold storage. Fruit stored in CA‐1 showed reduced CI and membrane lipid peroxidation after 5 and 8 weeks of cold storage. Low O2 atmospheres appeared to limit the generation of reactive oxygen species (ROS) and their efficient scavenging through the concerted action of superoxide dismutase and peroxidase. The role of ascorbate–glutathione (AsA–GSH) cycle in the regulation of oxidative stress was also studied during and after storage in different atmospheres. In conclusion, optimum CA conditions delayed fruit ripening and CI through augmentation of antioxidative metabolism and suppression of oxidative processes. 相似文献
52.
53.
Piyali Sarkar;Sayan Sarkar;Abhijit Nayek;Nayarassery N. Adarsh;Arun K. Pal;Ayan Datta;Abhishek Dey;Pradyut Ghosh; 《Small (Weinheim an der Bergstrasse, Germany)》2024,20(10):2304794
The advantage of a pre-organized π-cavity of Fe(II) complex of a newly developed macrobicycle cryptand is explored for CO2 reduction by overcoming the problem of high overpotential associated with the inert nature of the cryptate. Thus, a bipyridine-centered tritopic macrobicycle having a molecular π-cavity capable of forming Fe(II) complex as well as potential for CO2 encapsulation is synthesized. The inert Fe(II)-cryptate shows much lower potential in cyclic voltammetry than the Fe(II)-tris-dimethylbipyridine (Fe-MBP) core. Interestingly, this cryptate shows electrochemical CO2 reduction at a considerably lower potential than the Fe-MBP inert core. Therefore, this study represents that a well-structured π-cavity may generate a new series of molecular catalysts for the CO2 reduction reaction (CO2RR), even with the inert metal complexes. 相似文献
54.
Chang‐Kyu Hwang Jong Min Kim Sehoon Hwang Joo‐Hyung Kim Chang Hyun Sung Byung‐Moo Moon Keun Hwa Chae Jitendra Pal Singh Seung‐Hoon Kim Seung Soon Jang Seung Woo Lee Hyung Chul Ham Seunghee Han Jin Young Kim 《Advanced Materials Interfaces》2020,7(2)
The exploitation of state‐of‐the‐art Pt/C electrocatalysts for polymer electrolyte membrane fuel cells (PEMFCs) is mostly limited, due to high Pt loading and durability issues caused by electrochemical instability of the carbon support in high potential regimes. In this study, the authors report that high‐compressive 3D Pt nanostructured thin films can considerably increase the catalytic activity and electrochemical durability of electrocatalysts under PEMFC device operating conditions. The nanostructure fabrication relies on the dealloying or selective leaching of solid alloys of Pt–C binary film to produce a residual 3D nanoporous thin‐film structure. A very rich structural behavior from the dealloying is shown, in which stress relief plays a governing role; the films possess a 3D structure of randomly interpenetrating ligaments and hierarchical pores with sizes between less than 50 nm and several tens of micrometers. In addition, a significant change is observed in the average lattice constant (1.55% compressive strain), which can tune the structural and electronic states of catalytic sites for enhancing the activity of the Pt electrocatalysts. Electrochemical performance of the fabricated porous strained Pt thin‐film electrocatalysts in both half‐cell and single‐cell analyses has demonstrated activity and durability superior to benchmark carbon support Pt catalysts. 相似文献
55.
A novel coplanar waveguide fed UWB antenna with quad notch band characteristics has been proposed in this work. The antenna layout is designed based on a combination of well‐known geometrical shapes: a half ellipse patch, rectangle, and triangle. The shape of the ground plane is partially tapered rectangular. The overall dimension of the antenna is 41.5 × 32 mm. The antenna uses three U‐shaped slots at the top surface to create three notched band characteristics. A split‐ring resonator is then introduced at the bottom surface of the antenna. With the integration of split‐ring resonator at the bottom surface, an additional notch band at 7.25 to 7.75 (6.7%) GHz is created in the antenna. The designed antenna has an operating impedance bandwidth (VSWR ≤2) ranges from 3.03 to 12.34 GHz except in quad frequency stop bands of 3.3 to 3.7 (11.4%), 5.15 to 5.35 (3.8%), 5.725 to 5.825 (1.7%), and 7.25 to 7.75 (6.7%) GHz. The proposed antennas are successfully designed, prototyped, and measured. The simulated and measured results are extensively studied and discussed. Correlation between the time‐domain transmitting antenna input signal and the received antenna output signal is calculated in order to ensure that the proposed antenna can be used in pulse‐communication systems. This antenna finds applications in medical imaging, military radar systems, and other common UWB applications. 相似文献
56.
The objective of this paper is to identify and analyse the factors that influence offshore location decisions from an institutional theory perspective. In the years, emerging economies have shown great growth potential and have attracted significant foreign direct investment, especially from companies willing to set up operations. Despite such a seemingly favourable trade environment, not all companies that entered an emerging economy have been successful. Thus, there is a need to understand the factors that influence the success of any offshore location decision. It is also important to understand the relative importance of these factors, in order to develop novel insights useful to practitioners. There is a lack of literature addressing this issue, which this study aims to fill. We conducted a multi-case analysis with examples of European companies entering India. The findings indicate that successful companies employed locally focused business strategies that enabled them to acquire important relationships and knowledge, and also to adapt to formal institutions, including governmental and regulatory procedures. It was found that, irrespective of size, disregarding collaborative strategies was the main reason for exiting India. These findings are highly relevant for managers and policy makers. 相似文献
57.
Due to increase in global warming, it is very essential to use the non-conventional source of energy in place of conventional sources of energy. Cooling is one of the most critical requirements for humankind. It also requires the traditional source. Hence there should be alternative is necessary to reduce it. Present review paper shows the comprehensive review of the solar assisted cooling system. It includes various research work done by researchers from all around the world on Solar Assisted cooling system. From the comprehensive review, it has been found that the solar assisted cooling system is essential in today’s world. 相似文献
58.
The present work addresses optimization of these friction stir welding process variables to maximize joint strength efficiency of welded polycarbonate sheets by using particle swarm optimization algorithm over response surface method based regression model. Initially, parametric influence on weld quality characteristics namely weld bead profile, bead geometry with associated microstructure along with micro-hardness deviation through the weld centerline and stress-strain behavior of the weld have been studied in detail as per full factorial design of experiments by using three different tool pin profiles such as cylindrical, square and triangular. The center point experiment i. e. tool rotational speed of 1800 min−1 and welding speed of 20 mm/min, and square tool pin profile were found to be the optimum combination with a maximum joint strength efficiency of 60.06 %. The regression model of weld ultimate tensile strength was developed by using response surface methodology which was found to be significant. Therefore, this model was further used for parametric optimization by using both response surface methodology and intelligent particle swarm optimization approaches. A slight improvement in joint strength efficiency with better optimization capability was found by using particle swarm optimization technique as compared to response surface methodology. 相似文献
59.
The particle shape and size distribution of inorganic fillers play a crucial role in the scaffold buildability when those are incorporated in the viscoelastic polymers. In order to address this issue, the phase pure rod-shaped nanocrystalline hydroxyapatite (HAp) powders with varying particle sizes and shapes were synthesized by a one-pot hydrothermal method without any regulatory surfactant at an initial solution pH of 9. As-synthesized nanocrystalline HAp particles (0–5 wt%) were incorporated into 15 wt% pre-cross-linked gelatin methacryloyl (GelMA) hydrogel matrix to fabricate a predesigned scaffold architecture using a custom-made 3D bioprinter. The printing parameters (nozzle diameter, extrusion pressure, and printing speed) were optimized for each composition. The biophysical properties (uniaxial compression behavior, swelling ratio, and in vitro degradation) of the composite hydrogel scaffolds were critically analyzed to unravel the role of nano-sized HAp addition. The compression strength and modulus were substantially improved, while the rate of water uptake and bio-enzymatic degradation significantly reduced with HAp content. We propose that the inorganic–organic nanocomposite hydrogel could be efficiently assembled to formulate a potential bioink for 3D bioprinting applications toward tissue regeneration. 相似文献
60.
Ria Ghosh Soumendra Singh Dipanjan Mukherjee Susmita Mondal Monojit Das Uttam Pal Aniruddha Adhikari Aman Bhushan Surajit Bose Siddharth Sankar Bhattacharyya Debasish Pal Tanusri Saha-Dasgupta Maitree Bhattacharyya Debasis Bhattacharyya Asim Kumar Mallick Ranjan Das Samir Kumar Pal 《Chembiochem : a European journal of chemical biology》2022,23(9):e202200109
Drug delivery to a target without adverse effects is one of the major criteria for clinical use. Herein, we have made an attempt to explore the delivery efficacy of SDS surfactant in a monomer and micellar stage during the delivery of the model drug, Toluidine Blue (TB) from the micellar cavity to DNA. Molecular recognition of pre-micellar SDS encapsulated TB with DNA occurs at a rate constant of k1 ∼652 s−1. However, no significant release of encapsulated TB at micellar concentration was observed within the experimental time frame. This originated from the higher binding affinity of TB towards the nano-cavity of SDS at micellar concentration which does not allow the delivery of TB from the nano-cavity of SDS micelles to DNA. Thus, molecular recognition controls the extent of DNA recognition by TB which in turn modulates the rate of delivery of TB from SDS in a concentration-dependent manner. 相似文献