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11.
Nirman Ganguly Satyabrata Adhikari A. S. Majumdar 《Quantum Information Processing》2013,12(1):425-436
We investigate the issue of finding common entanglement witness for certain class of states and extend this study to the case of Schmidt number witnesses. We also introduce the notion of common decomposable and non-decomposable witness operators which is specially useful for constructing a common witness where one of the entangled states is with a positive partial transpose. Our approach is illustrated with the help of suitable examples of qutrit systems. 相似文献
12.
Discrepancies between experimentally measured data and computational predictions are unavoidable for complex engineering dynamical systems. To reduce this gap, model updating methods have been developed over the past three decades. Current methods for model updating often use discrete parameters, such as thickness or joint stiffness, for model updating. However, there are many parameters in a numerical model which are spatially distributed in nature. Such parameters include, but are not limited to, thickness, Poisson's ratio, Young's modulus, density and damping. In this paper a novel approach is proposed which takes account of the distributed nature of the parameters to be updated, by expressing the parameters as spatially correlated random fields. Based on this assumption, the random fields corresponding to the parameters to be updated have been expanded in a spectral decomposition known as the Karhunen–Loève (KL) expansion. Using the KL expansion, the mass and stiffness matrices are expanded in series in terms of discrete parameters. These parameters in turn are obtained using a sensitivity based optimization approach. A numerical example involving a beam with distributed updating parameters is used to illustrate this new idea. 相似文献
13.
Henrique AL Ribeiro Luis Sordo Vieira Yogesh Scindia Bandita Adhikari Matthew Wheeler Adam Knapp William Schroeder Borna Mehrad Reinhard Laubenbacher 《Journal of the Royal Society Interface》2022,19(189)
Aspergillus species are ubiquitous environmental moulds, with spores inhaled daily by most humans. Immunocompromised hosts can develop an invasive infection resulting in high mortality. There is, therefore, a pressing need for host-centric therapeutics for this infection. To address it, we created a multi-scale computational model of the infection, focused on its interaction with the innate immune system and iron, a critical nutrient for the pathogen. The model, parameterized using published data, was found to recapitulate a wide range of biological features and was experimentally validated in vivo. Conidial swelling was identified as critical in fungal strains with high growth, whereas the siderophore secretion rate seems to be an essential prerequisite for the establishment of the infection in low-growth strains. In immunocompetent hosts, high growth, high swelling probability and impaired leucocyte activation lead to a high conidial germination rate. Similarly, in neutropenic hosts, high fungal growth was achieved through synergy between high growth rate, high swelling probability, slow leucocyte activation and high siderophore secretion. In summary, the model reveals a small set of parameters related to fungal growth, iron acquisition and leucocyte activation as critical determinants of the fate of the infection. 相似文献
14.
15.
Xiao-Fei Wu Benu Adhikari Jincai Sun 《Critical reviews in food science and nutrition》2017,57(17):3620-3631
This article reviews the recent developments in novel freezing and thawing technologies applied to foods. These novel technologies improve the quality of frozen and thawed foods and are energy efficient. The novel technologies applied to freezing include pulsed electric field pre-treatment, ultra-low temperature, ultra-rapid freezing, ultra-high pressure and ultrasound. The novel technologies applied to thawing include ultra-high pressure, ultrasound, high voltage electrostatic field (HVEF), and radio frequency. Ultra-low temperature and ultra-rapid freezing promote the formation and uniform distribution of small ice crystals throughout frozen foods. Ultra-high pressure and ultrasound assisted freezing are non-thermal methods and shorten the freezing time and improve product quality. Ultra-high pressure and HVEF thawing generate high heat transfer rates and accelerate the thawing process. Ultrasound and radio frequency thawing can facilitate thawing process by volumetrically generating heat within frozen foods. It is anticipated that these novel technologies will be increasingly used in food industries in the future. 相似文献
16.
Jackson LS Beacham-Bowden T Keller SE Adhikari C Taylor KT Chirtel SJ Merker RI 《Journal of food protection》2003,66(4):618-624
Patulin is a mycotoxin produced primarily by Penicillium expansum, a mold responsible for rot in apples and other fruits. The growth of this fungus and the production of patulin are common in fruit that has been damaged. However, patulin can be detected in visibly sound fruit. The purpose of this project was to determine how apple quality, storage, and washing treatments affect patulin levels in apple cider. Patulin was not detected in cider pressed from fresh tree-picked apples (seven cultivars) but was found at levels of 40.2 to 374 microg/liter in cider pressed from four cultivars of fresh ground-harvested (dropped) apples. Patulin was not detected in cider pressed from culled tree-picked apples stored for 4 to 6 weeks at 0 to 2 degrees C but was found at levels of 0.97 to 64.0 microg/liter in cider pressed from unculled fruit stored under the same conditions. Cider from controlled-atmosphere-stored apples that were culled before pressing contained 0 to 15.1 microg of patulin per liter, while cider made from unculled fruit contained 59.9 to 120.5 microg of patulin per liter. The washing of ground-harvested apples before pressing reduced patulin levels in cider by 10 to 100%, depending on the initial patulin levels and the type of wash solution used. These results indicate that patulin is a good indicator of the quality of the apples used to manufacture cider. The avoidance of ground-harvested apples and the careful culling of apples before pressing are good methods for reducing patulin levels in cider. 相似文献
17.
ABSTRACT: Physical aging of amorphous anhydrous fructose at temperature 5 °C and at 22 °C was studied using differential scanning calorimetry (DSC). The dynamic glass transition temperature, Tg0 for unaged samples was 16 °C and 13.3 °C for heating rate of 10 °C/min and 1 °C/min, respectively. The fictive temperature, Tf0 for unaged samples calculated by Richardson and Savill method was 12 °C, which is close to the dynamic value obtained from the lower DSC heating rate. The fictive temperature Tf of the aged fructose glasses at temperatures both below and above the transition region was fitted well by a non-exponential decay function (Williams-Watts form). Aging above the transition region (22 °C) for 18 d increased both the dynamic glass transition temperature Tg and the fictive temperature Tf . However, aging below the transition region (5 °C) for 1 d increased the dynamic glass transition temperature Tg but decreased the fictive temperature Tf . 相似文献
18.
This study evaluated the efficacy of ultrasound treatment and nano-zinc oxide (ZnO) coating individually and in combination in preserving the quality of fresh-cut kiwifruit. The nano-ZnO coating solution was prepared by mixing the ZnO nanoparticles in premixed chitosan–acetic acid solution. The fresh-cut kiwifruit were dipped in NaClO solution (50 μL?L?1 sodium, control), subjected to ultrasound treatment (40 KHz, 350 W, 10 min), or coated with nano-ZnO solution. The fresh-cut kiwifruit samples were also subjected to combined ultrasound treatment and nano-ZnO coating. All of these test samples were stored at 4 °C for 10 days. The effects of these treatments on the quality parameters such as the production of carbon dioxide and ethylene, mass loss, and flesh firmness were investigated. At the end of storage, the combination treatments with ultrasound treatment at 40 KHz with 1.2 g?L?1 nano-ZnO coating showed lower production of ethylene (1.86 μL?kg?1?h?1) and carbon dioxide (10.01 mg?kg?1?h?1), water loss (0.46 %), and texture (7.87 N). Hence, it was concluded that the combination of ultrasound treatment with nano-ZnO coating is a promising approach to extend the shelf-life of fresh-cut kiwifruit. 相似文献
19.
Freezing characteristics (freezing time, latent heat of fusion of ice, and freezable water content) and quality parameters (drip loss, color, firmness, and l-ascorbic acid content) of broccoli (osmodehydrofrozen and ultrasound-assisted osmodehydrofrozen) during frozen storage were investigated. Freezing time, latent heat of fusion of ice, and freezable water content of osmodehydrated samples decreased significantly compared to samples which were not under osmotic dehydration. The changes of drip loss, color, firmness, and l-ascorbic acid content of osmodehydrofrozen and ultrasound-assisted osmodehydrofrozen broccoli during frozen storage were inhibited markedly compared to samples which were not submitted to osmotic dehydration before freezing. Compared to osmotic dehydration, the ultrasound-assisted osmotic dehydration shortened the needed dehydration time and better preserved the firmness and l-ascorbic acid content after osmotic dehydration pretreatment. In addition, the ultrasound-assisted osmotic dehydration minimized the drip loss and loss of l-ascorbic acid content and better maintained the color and firmness when stored at ?25 °C for 6 months. These findings indicate that it is promising to apply ultrasound-assisted osmodehydrofreezing in freezing and frozen storage of food. 相似文献
20.
Ultrahigh temperature water gas shift catalysts to increase hydrogen yield from biomass gasification 总被引:1,自引:0,他引:1
Noble metal (Rh, Pt, Pd, Ir, Ru, and Ag) and Ni catalysts supported on CeO2–Al2O3 were investigated for water gas shift reaction at ultrahigh temperatures. Pt/CeO2–Al2O3 and Ru/CeO2–Al2O3 demonstrated as the best catalysts in terms of activity, hydrogen yield and hydrogen selectivity. At 700 °C and steam to CO ratio of 5.2:1, Pt/CeO2–Al2O3 converted 76.3% of CO with 94.7% of hydrogen selectivity. At the same conditions, the activity and hydrogen selectivity for Ru/CeO2–Al2O3 were 63.9% and 85.6%, respectively. Both catalysts showed a good stability over 9 h of continuous operation. However, both catalysts showed slight deactivation during the test period. The study revealed that Pt/CeO2–Al2O3 and Ru/CeO2–Al2O3 were excellent ultrahigh temperature water gas shift catalysts, which can be coupled with biomass gasification in a downstream reactor. 相似文献