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991.
Analysis of products, mechanisms of reaction, and some functional properties of soy protein hydrolysates 总被引:11,自引:0,他引:11
Sara E. Molina Ortiz Mara Cristina An 《Journal of the American Oil Chemists' Society》2000,77(12):1293-1301
Soybean protein isolates were hydrolyzed with papain, bromelain, cucurbita, hieronymin, and pomiferin. The highest hydrolysis
rate for cucurbita and the lowest for papain was detected at 720 min. Gel filtration, reversed-phase liquid chromatography,
and electrophoresis showed that the action of each protease was different. Pomiferin acted on the native structure of β-conglycinin
and glycinin, generating a large number of small hydrolysis products with hydrophilic and hydrophobic characteristics. The
hydrolysates obtained with cucurbita showed residual structures that were almost intact and very similar to the substrate
and contained a low number of small peptides. The hydrolyzates obtained with papain, bromelain, and hieronymin had hydrolysis
products with structures similar to the partially hydrolyzed native isolate. The molecular masses of these products were similar
to or lower than the controls. Polypeptides of low molecular mass were also detected. The prevalence of one-by-one and zipper
mechanisms was suggested for cucurbita and pomiferin, respectively. For the other proteases both mechanisms were likely to
coexist. The solubility of hydrolysates and their ability to form and stabilize foams correlated well with the structural
properties and with the suggested mechanisms of hydrolysis. The best properties were presented by the hydrolysates prepared
with cucurbita. Foaming ability for pomiferin hydrolysates was as high as that for unhydrolyzed soy isolate, but the foams
were extremely unstable. 相似文献
992.
Paolo Basso Sara Casciati Lucia Faravelli 《Structure and Infrastructure Engineering》2015,11(1):27-37
The evolution of the railway traffic during the last century is studied as preliminary step towards the estimation of the remaining service life of a historical bridge. The selected case study concerns the El Ourit Bridge, designed in 1889 by Gustave Eiffel and located close to the town of Tlemcen, in Algeria. A finite element model of the structure is built and the response of the bridge to train-crossing loads is numerically evaluated with the purpose of identifying the element most affected by stress variations. The Palmgren–Miner accumulation model is used to quantify the fatigue damage in this element. A limit state function based on this criterion is formulated; then, a fully probabilistic approach is adopted by assuming that the stress amplitude, the fatigue strength and the damage threshold value play the role of random variables. The obtained results are discussed in order to evaluate the residual service life of the bridge. 相似文献
993.
Quality of service analysis and improvement with cross layer power allocation in multirelay networks
Quality of service (QoS) guarantee is the main performance metric for designing future wireless networks. For real time applications over wireless links, statistical delay QoS guarantee is the most important QoS metrics. The main goal of this paper is studying the effects of multi‐decode‐and‐forward‐relaying transmission on delay QoS guarantee and user satisfaction. For this end, we first propose an approach to simplify the analysis of statistical delay QoS guarantee by the use of a curve named QoS analysis curve. The QoS analysis curve of any system is based on its effective capacity (EC) function. So, we derive a closed‐form expression for the EC function of a multi‐decode‐and‐forward‐relay network to reduce the computational complexity of finding this quantity. After that, for improving the QoS guarantee performance of a multi‐decode‐and‐forward‐relaying system, the EC of the system is maximized by the use of power allocation (PA) technique. At first, an adaptive PA (APA) algorithm is proposed in which the source and relays PA policies are derived analytically. Although, the overhead of this algorithm is large, it significantly improves the statistical delay QoS guarantee performance. Then, for the systems that cannot tolerate the required large overhead of APA, a fixed PA scheme is presented, which is based on particle swarm optimization algorithm. There is a tradeoff between providing the delay QoS guarantee and the required overhead, in selecting APA or fixed PA schemes. The numerical results validate our analytical outcomes and evaluate our proposed algorithms. 相似文献
994.
Bioactive Gyroid Scaffolds Formed by Sacrificial Templating of Nanocellulose and Nanochitin Hydrogels as Instructive Platforms for Biomimetic Tissue Engineering 下载免费PDF全文
995.
996.
Zahid Anwar Nowreen Sara Islam M. Kamrul Hassan M. Rashidul Hossain M. Jakir Abbassi Salah Uddin 《Bulletin of Engineering Geology and the Environment》2021,80(8):5941-5955
Bulletin of Engineering Geology and the Environment - Various studies have described upon importance of the performance of multilevel slug tests to assess hydraulic conductivity of aquifer... 相似文献
997.
Hatem A. Abdel-Aziz Wagdy M. Eldehna Mohamed Fares Sara T. A. Al-Rashood Khalid A. Al-Rashood Marwa M. Abdel-Aziz Dalia H. Soliman 《International journal of molecular sciences》2015,16(4):8719-8743
In continuation of our endeavor towards the development of potent and effective antimicrobial agents, three series of halophenyl bis-hydrazones (14a–n, 16a–d, 17a and 17b) were synthesized and evaluated for their potential antibacterial, antifungal and antimycobacterial activities. These efforts led to the identification of five molecules 14c, 14g, 16b, 17a and 17b (MIC range from 0.12 to 7.81 μg/mL) with broad antimicrobial activity against Mycobacterium tuberculosis; Aspergillus fumigates; Gram positive bacteria, Staphylococcus aureus, Streptococcus pneumonia, and Bacillis subtilis; and Gram negative bacteria, Salmonella typhimurium, Klebsiella pneumonia, and Escherichia coli. Three of the most active compounds, 16b, 17a and 17b, were also devoid of apparent cytotoxicity to lung cancer cell line A549. Amphotericin B and ciprofloxacin were used as references for antifungal and antibacterial screening, while isoniazid and pyrazinamide were used as references for antimycobacterial activity. Furthermore, three Quantitative Structure Activity Relationship (QSAR) models were built to explore the structural requirements controlling the different activities of the prepared bis-hydrazones. 相似文献
998.
Thermophysical Properties of Short Carbon Fiber/SiC Multilayer Composites Prepared by Tape Casting and Pressureless Sintering 下载免费PDF全文
Wenshu Yang Sara Biamino Elisa Padovano Matteo Pavese Paolo Fino Claudio Badini 《International Journal of Applied Ceramic Technology》2015,12(3):510-521
Csf/SiC multilayer composites for thermal conductivity (TC) test in three directions were successively prepared by tape casting and pressureless sintering. After 1500°C/5 h oxidation treatment, short carbon fibers were oxidized which produced many pores. However, a core area, which was composed by short carbon fiber, SiC, and few SiO2, was still observed. TC properties of Csf/SiC multilayer composites were highly anisotropic. The TC was decreased with the increase in fiber amount. Csf/SiC multilayer composites demonstrated the highest TC along the tape casting direction and the lowest TC through the thickness direction, which is favorable for thermal protection purpose. 相似文献
999.
Alfredo M. Gravagnuolo Eden Morales‐Narváez Sara Longobardi Everson T. da Silva Paola Giardina Arben Merkoçi 《Advanced functional materials》2015,25(18):2771-2779
Biological interfacing of graphene has become crucial to improve its biocompatibility, dispersability, and selectivity. However, biofunctionalization of graphene without yielding defects in its sp2‐carbon lattice is a major challenge. Here, a process is set out for biofunctionalized defect‐free graphene synthesis through the liquid phase ultrasonic exfoliation of raw graphitic material assisted by the self‐assembling fungal hydrophobin Vmh2. This protein (extracted from the edible fungus Pleurotus ostreatus) is endowed with peculiar physicochemical properties, exceptional stability, and versatility. The unique properties of Vmh2 and, above all, its superior hydrophobicity, and stability allow to obtain a highly concentrated (≈440–510 μg mL?1) and stable exfoliated material (ζ‐potential, +40/+70 mV). In addition controlled centrifugation enables the selection of biofunctionalized few‐layer defect‐free micrographene flakes, as assessed by Raman spectroscopy, atomic force microscopy, scanning electron microscopy, and electrophoretic mobility. This biofunctionalized product represents a high value added material for the emerging applications of graphene in the biotechnological field such as sensing, nanomedicine, and bioelectronics technologies. 相似文献
1000.
Electrical Junctions: The Relationship between Structural and Electrical Characteristics in Perylenecarboxydiimide‐Based Nanoarchitectures (Adv. Funct. Mater. 17/2015) 下载免费PDF全文