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81.
The occurrence of low temperature sweetening in Brussica juncen L., an apparently chilling-tolerant leafy vegetables, has been investigated in relation to the effect of water stress and postharvest age (i.e. fresh harvest vs previously stored samples). The magnitude of cold-induced sweetening in B. juncea leaves was estimated to vary from 10–145% relative to the corresponding nonchilled samples. Previously stored leaves showed greater tendency to accumulate sugars but was apparently less responsive to cold-induced sweetening than freshly harvested leaves. Water stress synergistically enhanced this low temperature sweetening response; markedly greater and/or faster accumulation of sugars occurred in leaves that were both chilled and stressed. The majority of the total sugar increase was attributable to non-reducing sugars. 相似文献
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83.
Whole apples were compressed uni-axially with the core at right angles (horizontal compression) and parallel (vertical compression) to the direction of force. Under horizontal compression, the apple begins to bruise as soon as force is applied. The energy absorbed is proportional to the volume of bruise produced. Resistance to bruising varies with variety. In this orientation the fruit does not deform elastically, bruises easily, and the skin is not important in preventing bruising. Under vertical compression the apple is a much more elastic structure and can expand laterally. It can withstand greater deformation without damage. Rock Pippin can elastically absorb up to 0.5 J before damage. In this orientation, skin plays an important part in preventing cracking under tension. Any damage to the skin greatly reduces the structural strength of the fruit and renders it much more susceptible to cracking. Apples stacked in boxes seldom experience energies greater than 0.5 J. Storing apples in a vertical orientation can therefore reduce risk of bruising. 相似文献
84.
AGHA Z. KHAN ALI SHER BHATTI M. ZAHID RAZA NISAR AHMAD 《Petroleum Science and Technology》2013,31(8):973-990
Abstract The Makerwal coal of Pakistan gives higher extractibi1ity with Tetrahydrofuran ( THF ) as compared to Sharigh, Sor-Range and Lakhra coals. The structural characterization of Pakistan coal extracts by FT-IR spectroscopy indicates that all the extracts contained less condensed aromatic rings in comparision to their original coal. 相似文献
85.
Rahat MASOOD Muhammad Awais SHIBLI Yumna GHAZI Ayesha KANWAL Arshad ALI 《Frontiers of Computer Science》2015,9(2):297
Despite the various attractive features that Cloud has to offer, the rate of Cloud migration is rather slow, primarily due to the serious security and privacy issues that exist in the paradigm. One of the main problems in this regard is that of authorization in the Cloud environment, which is the focus of our research. In this paper, we present a systematic analysis of the existing authorization solutions in Cloud and evaluate their effectiveness against well-established industrial standards that conform to the unique access control requirements in the domain. Our analysis can benefit organizations by helping them decide the best authorization technique for deployment in Cloud; a case study along with simulation results is also presented to illustrate the procedure of using our qualitative analysis for the selection of an appropriate technique, as per Cloud consumer requirements. From the results of this evaluation, we derive the general shortcomings of the extant access control techniques that are keeping them from providing successful authorization and, therefore, widely adopted by the Cloud community. To that end, we enumerate the features an ideal access control mechanisms for the Cloud should have, and combine them to suggest the ultimate solution to this major security challenge – access control as a service (ACaaS) for the software as a service (SaaS) layer. We conclude that a meticulous research is needed to incorporate the identified authorization features into a generic AcaaS framework that should be adequate for providing high level of extensibility and security by integrating multiple access control models. 相似文献
86.
In the present paper an attempt has been made to study the changes in the mixed layer depth (MLD) along the Equatorial Indian Ocean in response to sea level variations as obtained from Geosat Altimeter data. The analysis has been carried out for the entire Geosat period. The equatorial sea surface slope shows marked seasonal dependency. The rms error between MLD calculated from Geosat altimeter sea surface heights (MLDs) and that obtained from temperature profiles (MLDt) is 20 m. The interseasonal comparison on zonal mixed layer slope indicates deepening of MLD towards the eastern side of the Equatorial Indian Ocean during south west monsoon period. The MLD calculated from altimeter observations differs largely from that obtained from temperature profiles towards the extreme east of the study area due to the north/south propagation of surface water in addition to zonal flow. 相似文献
87.
88.
RATNA R. SHARMA ALI DEMIRCI LARRY R. BEUCHAT WILLIAM F. FETT 《Journal of Food Safety》2002,22(2):107-119
Alfalfa seeds inoculated with Escherichia coli O157:H7 (～105 CFU/g) were subjected to low hydrostatic pressure. Seeds immersed in ozonated water at 4C were held at 8 and 12‐psi ozone pressure for 2, 4, 8, 16, 32, and 64 min. Alternatively, seeds were continuously sparged with ozone for up to 64 min and then held at 12 psi for 5 min. Controls consisted of sparging and pressurization with air. Thirty‐two minute treatments of continuous ozone sparging followed by pressurization of seeds at 12 psi for 5 min were repeated with the addition of four surfactants (Tween 20, Tween 80, SPAN 20, and SPAN 80) in the treatment water. Enumeration of E. coli O157:H7 on treated, untreated, and control seeds was done on tryptic soy agar supplemented with 50 μg/mL of nalidixic acid. The reduction in population of E. coli O157:H7 on seeds treated with the 8 and 12 psi hydrostatic pressure in ozonated water ranged from 0.74 ?1.56 log10 CFU/g and 0.72 – 1.62 log10 CFU/g, respectively. Control treatments carried out with air pressurization of seeds resulted in maximum population reductions of 1.55 log10 and 1.83 log10 CFU/g for 8 and 12 psi, respectively. For seeds treated with continuous ozone sparging (2 – 64 min) followed by pressurization at 12 psi for 5 min, the highest reduction was 2.03 log10 CFU/g. Reductions were, however, not significantly different (P > 0.05) from control treatment (with air) which reduced the populations by 0.57 – 2.19 log10 CFU/g. The presence of surfactants during continuous sparging of water followed by pressurization at 12 psi was not beneficial. None of the treatments adversely affected the germination of the seeds. 相似文献
89.
90.
Sugar and mineral compositions of 10 Tunisian date varieties were investigated. Hydrophilic (aqueous extract) and hydrophobic extracts (ethanol extract) were used to determine the phenol contents and the total antioxidant activities of these dates. Results showed that date fruit varieties were rich in soluble sugars, which varied from 35.57 (Smiti variety) to 77.88 g/100 g fresh weight (FW) (Korkobbi variety). Several minerals were also present in the following order; K, Ca, P, Mg, Na, Fe, Cu, Zn and Mn. The potassium content reached 0.74 g/100 g dry weight in Smiti variety. For all date varieties, the phenol content did not exceed 9.70 (milligram of gallic acid equivalent/100 g FW). The original antioxidant activity reached 31.86 mg of ascorbic acid equivalent antioxidant capacity/100 g (FW) for Garn ghzal variety. However, it was only 17.77 for the Nefzaoui. Therefore, it can be deduced from these results that all these fruit varieties can be considered as high-energy food and only Garn ghzal seems to be interesting for technological purposes as food antioxidants.
The date palm ( Phoenix dactylifera L.) has a very important economic, social and ecological role for the people of the arid and semiarid regions. The date world production tripled while passing from 2,289,511 tons in 1974 to 6,772,068 tons in 2004. In Tunisia, dates witnessed a remarkable development during the last years and the production reached an average of 110,000 tons per year. Unfortunately, this progress in production is accompanied by an increasing loss of secondary varieties. Among these abandoned varieties are those of Gabès oasis. In this context, our work focuses on valorizing these secondary varieties by determining their nutritional and medicinal properties. 相似文献
PRACTICAL APPLICATIONS
The date palm ( Phoenix dactylifera L.) has a very important economic, social and ecological role for the people of the arid and semiarid regions. The date world production tripled while passing from 2,289,511 tons in 1974 to 6,772,068 tons in 2004. In Tunisia, dates witnessed a remarkable development during the last years and the production reached an average of 110,000 tons per year. Unfortunately, this progress in production is accompanied by an increasing loss of secondary varieties. Among these abandoned varieties are those of Gabès oasis. In this context, our work focuses on valorizing these secondary varieties by determining their nutritional and medicinal properties. 相似文献