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81.
Deficit irrigation strategies enhance health‐promoting compounds through the intensification of specific enzymes in early peaches
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![点击此处可从《Journal of the science of food and agriculture》网站下载免费的PDF全文](/ch/ext_images/free.gif)
82.
Rocio Velázquez Alejandro Hernández Alberto Martín Emilio Aranda Gustavo Gallardo Teresa Bartolomé Maria G. Córdoba 《International Journal of Food Science & Technology》2014,49(3):830-839
Several quality parameters of smoked, oven‐dried and sun‐dried paprikas were studied. Smoked paprikas showed the highest American Spice Trade Association (ASTA) units and pigment concentrations, whereas oven‐dried paprikas showed the best browning index and red/yellow pigment ratio, and sun‐dried paprikas had the highest redness for reflected colour. The colour stability results showed drastic overall colour change (ΔE) and decreased redness and ASTA units of the sun‐dried and oven‐dried paprikas after two and 5 days of UV exposure. Degradation of the smoked paprika colour parameters was progressive, and they showed less degradation even after 30 days. The evaluation of the antioxidant activity showed higher DPPH radical‐scavenging capacity in the smoked samples. The profiles of volatile phenolic compounds of the smoked samples are responsible for the differences in the antioxidant capacity. The great differences in colour stability and antioxidant activity make smoked paprika the best choice for use in the food industry. 相似文献
83.
Stability of the antimicrobial activity of acetogenins from avocado seed,under common food processing conditions,against Clostridium sporogenes vegetative cell growth and endospore germination
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Adriana Pacheco Dariana Graciela Rodríguez‐Sánchez Raúl Villarreal‐Lara Jesús Manuel Navarro‐Silva Carolina Senés‐Guerrero Carmen Hernández‐Brenes 《International Journal of Food Science & Technology》2017,52(11):2311-2323
Anticlostridial activity of acetogenins from avocado seed was further characterised, and their stability and effectiveness under food processing conditions, and in a model food system, studied for the first time. Isolated AcO‐avocadenyne (1) and AcO‐avocadene (2) showed anticlostridial potential, particularly the latter molecule. Enriched acetogenins extracts, obtained at laboratory scale (EAE) and semi‐commercially (Avosafe®), presented similar MIC values (3.9–9.8 ppm) and a bacteriostatic effect. Extracts bioactivity showed resistance to heat (≤120 °C), high hydrostatic pressure (HHP; 300–600 MPa, 3–6 min, 25 °C) and salt (≤3% w/v). In addition, the extract was most stable at pH ≥ 7.0 and potency against endospores increased after HHP treatment and exposure to pH 9.5, suggesting a positive effect on solubility or structure of particular acetogenins. In a model food system processed by HHP, acetogenins were retained; however, initial quantities gradually declined by 63% and 32% at 25 and 4 °C, respectively, at the end of the storage period (42 days). Most stable molecules (persediene (4) > persenones > AcO‐avocadene (2)) possess a keto or trans‐enone group at C‐4 in the aliphatic chain, which could support hydrogen donation to surrounding carbon atoms and confer antioxidant activity. Active endospores were completely inhibited by 5000 ppm Avosafe® in the model food system (37 °C, 72 h) and lower concentrations (500–1000 ppm) resulted in 1–2 log reduction of a 3 log inoculum target. Efficacy information generated in the present work is considered crucial to improve scientific knowledge on spore inhibition properties of avocado acetogenins. 相似文献
84.
Salvador Ros Agustín C. Caminero Roberto Hernández Antonio Robles-Gómez Llanos Tobarra 《The Journal of supercomputing》2014,68(3):1556-1578
In cloud systems, a clear necessity emerges related to the use of efficient and scalable computing resources. For this, accurate predictions on the load of computing resources are a key. Thanks to these accurate predictions, reduced power consumption and enhanced revenue of the system can be achieved, since resources can be ready when users need them and shutdown when they are no longer needed. This work presents an architecture to manage web applications based on cloud computing, which combines both local and public cloud resources. This work also presents the algorithms needed to efficiently manage such architecture. Among them, a load forecasting algorithm has been developed based on Exponential Smoothing. An use case of the e-learning services of our University presenting the behaviour of our architecture has been evaluated through a series of simulations. Among the most remarkable results, power consumption is reduced by 32 % at the cost of 367.31 US$ a month compared with the current architecture. 相似文献
85.
86.
87.
Summary
In the last decade the recycling of different types of waste has become a worldwide necessity. A large amount of polymeric
material is generated in the health care sector and nowadays, due to a lack of technology and stiff government regulations,
most of this material is incinerated thereby causing other type of problems. In this paper, a study of the degradation and
possible reutilization of the polypropylene used in the fabrication of disposable syringes is done. The main idea is to use
this polymer as the matrix and carbon black as the filler in an electrically conductor composite with proper a thermal properties
for applications such as a heating material.
Received: 11 September 2000/Revised version: 17 November 2000/Accepted: 17 November 2000 相似文献
88.
Summary
Two novel polymers containing p-nitroaniline group in the side chain and diacetylene groups in the main chain, were synthesized, and characterized. The polymers
gave films of excellent optical quality by spin coating from DMF or chloroform. The one containing benzoate had a Tg of 103°C and its thermal cross-linking through the diacetylene group started at around 160°C. The one containing pentynoate
had a Tg of 35°C and its cross-linking started at around 120°C. It was shown that thermosetting resins with functional groups could
be obtained by using diacetylene-containing polymers. Although these two polymers have a same polar dye molecule, the second
order nonlinear optical property was so different, showing that the main chains are very important for nonlinear optical property.
Irradiation of UV light converted the polymer films to completely insoluble thermoset resins.
Received: 13 February 2001/Revised version: 25 July 2001/Accepted: 30 July 2001 相似文献
89.
Characterization of novel hyaluronic acid matrix systems for vaginal administration of metronidazole
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Polymers such as Hyaluronic acid (HA), Polyethylene glycol‐400 (PEG‐400) and Xanthan Gum (XG) are promising in drug delivery applicationsbecause of their biomedical and pharmaceutical potential applications. In HA 2%‐PEG 400 systems, the effect of pH and PEG‐400 concentration were evaluated. The viscosity of HA‐PEG 400 formulations slightly increased with PEG‐400 concentration. Viscoelastic properties and shear thinning character was strongly dependent on pH. Structured systems were obtained at pH 3, with an increase of several orders of magnitude in zero‐shear viscosity values. When XG 1% structured system is added on HA (0, 0.5, and 2%) and PEG‐400 5%, a sharp increase of viscosity can be observed, obtaining a gel‐like behaviour for HA 0.5%‐XG 1%‐PEG 400 5% formulation. Finally, metronidazole release profiles in HA 2% formulations with different PEG‐400 concentrations at pH 4.5 were studied. At least 90% of metronidazole was releasedat 24 h. However, the addition of XG 1% to the HA (0.5 and 2%)‐PEG 400 5% systems delayed the drug release. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41313. 相似文献
90.
Optical and Structural Properties of ZnO and ZnO:Cd Particles Grown by the Hydrothermal Method
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Diego A. Guzmán‐Embús Maria F. Vargas‐Charry Carlos Vargas‐Hernández 《Journal of the American Ceramic Society》2015,98(5):1498-1505
Here, we examine the structural, vibrational, optical, and morphological properties of ZnO particles synthesized by the hydrothermal method, incorporating cadmium at different concentrations through the molar ratio Rm = Cd+2/Zn+2 and a thermal treatment at 500°C. The X‐ray diffraction results demonstrated the high crystallinity of the ZnO compound with a wurtzite‐type hexagonal structure. The Raman scattering spectra demonstrated that the ZnO vibrational modes occur in the region between 200 and 1300 cm?1, which is associated with different vibrational configurations characteristic of the ZnO molecule: E2(Low), E2(M), A1(TO) E1(TO), 2B1(High), E2(High), and TA + LO. The modes that were most affected by the incorporation of Cd2+ were those assigned to 2E2(Low), E2(M), and 2B1(High), and this effect was associated with a greater displacement of Zn2+ ions. The optical study showed a reduction in the band gap and a decrease in the crystalline quality due to the substitution of Cd2+ in the ZnO lattice. Cadmium incorporation affected the morphology of the ZnO:Cd particles, changing the lengths and diameters of the ZnO rods; when the Cd concentration was increased, the ZnO rods shortened, forming coin‐type hexagonal structures. 相似文献