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991.
Spalazzi Luca Paolanti Marina Frontoni Emanuele 《Multimedia Tools and Applications》2022,81(16):22715-22730
Multimedia Tools and Applications - Nowadays, the volume of the multimedia heterogeneous evidence presented for digital forensic analysis has significantly increased, thus requiring the application... 相似文献
992.
Idalia Osuna‐Ruíz Gloria Yepiz‐Plascencia Ofelia Rouzaud‐Sández Josafat Marina Ezquerra‐Brauer 《International Journal of Food Science & Technology》2010,45(2):387-394
An aminopeptidase (AP) was partially purified from jumbo squid (Dosidicus gigas) hepatopancreas with 154.24‐fold and yield of 6.15%. The purification procedure consisted of ammonium sulphate fractionation and DEAE‐Sephacel chromatography. The enzyme was approximately 48–53 kDa as estimated by SDS‐PAGE. With l ‐leu‐p‐NA, it had optimum activity at pH 8.0 and 30 °C. The Km and Vmax/Km values of the enzymes for l ‐leu‐p‐NA were 0.326 mm and 2787 at 37 °C, respectively. Activation energy (Ea) of the enzyme was 53.50 kJ M?1.The AP showed activity against seven synthetic substrates: l ‐proline>l ‐methionine>Ac. l ‐γ‐glutamic>l ‐glycine>l ‐leucine>l ‐alanine>l ‐lysine‐p‐NA. The enzyme was strongly inhibited by Bestatin, partially inhibited by a metal‐chelating agent and by PCMB, a cystein protease inhibitor. Zn2+ and (or) Ca2+ seemed to be its metal cofactor(s). Incubation of casein with the partially purified AP resulted in a degree of hydrolysis of 6%. 相似文献
993.
994.
Georgiy B. Shul’pin Marina V. Kirillova Tawan Sooknoi Armando J. L. Pombeiro 《Catalysis Letters》2008,123(1-2):135-141
Hydrogen peroxide oxidizes alkanes at room temperature to produce the corresponding alkyl hydroperoxides in the presence of titanosilicalite-1, NaOH and acetonitrile. The reaction proceeds with low regio- and bond-selectivity and its mechanism apparently involves the formation of hydroxyl radicals. 相似文献
995.
Adriana Zulema Valencia-Pérez Miriam Hiessu García-Morales José Luis Cárdenas-López José Ronaldo Herrera-Urbina Ofelia Rouzaud-Sández Josafat Marina Ezquerra-Brauer 《Food chemistry》2008
The effect of two thermal treatments (fast freezing at −40 °C and vapor cooking at 100 °C) on connective tissue extract (CTE) from jumbo squid (Dosidicus gigas) was investigated. Samples of CTE frozen at −40 °C were taken at 0, 3, 5 and 12 min. Also CTE was cooked at 100 °C and samples were taken at 0, 1, 2.5 and 5 min. Light microscopic observations of CTE after 12 min of freezing showed rupture of fibres. The CTE fibres showed agglutination during cooking time. The CTE insoluble fraction increased with freezing and cooking time. Maximum zeta potential value of untreated CTE was detected at pH 5.0 at +30 mV, meanwhile in the frozen CTE it was detected at pH 7.0 at +30 mV and two peaks (at pH 5.5 and 9.0) were observed at +20 mV in the cooked CTE. One endothermic peak was found at 105.9 °C in the untreated CTE, while in the frozen and cooked CTE the endothermic peaks were found at lower temperatures and enthalpies. Electrophoresis analysis of untreated CTE showed three bands. In the frozen CTE two bands appeared above 200 kDa, and in the cooked CTE, a 45 kDa band disappeared. These results suggest that during freezing and cooking processes there were modifications to molecular bonds that hold the integrity of the structure of the connective tissue of the jumbo squid mantle. 相似文献
996.
Catia Arbizzani Sabina BeninatiFrancesca Soavi Alberto VarziMarina Mastragostino 《Journal of power sources》2008
We prepared and characterized several cryogel mesoporous carbons of different pore size distribution and report the catalytic activity of PtRu supported on mesoporous carbons of pore size >15 nm in passive and in active direct methanol fuel cells (DMFCs). At room temperature (RT), the specific maximum power of the passive DMFCs with mesoporous carbon/PtRu systems as anode was in the range 3–5 W g−1. Passive DMFC assembly and RT tests limit the performance of the electrocatalytic systems and the anodes were thus tested in active DMFCs at 30, 60 and 80 °C. Their responses were also compared to those of commercial Vulcan carbon/PtRu. At 80 °C, the specific maximum power of the active DMFC with C656/PtRu was 37 W g−1 and the required amount of Pt per kW estimated at 0.4 V cell voltage was 31 g kW−1, a value less than half that of Vulcan carbon/PtRu. 相似文献
997.
Boris A. Trofimov Marina V. Markova Lyudmila V. Morozova Al’bina I. Mikhaleva Lyubov’ N. Sobenina Ol’ga V. Petrova Tamara I. Vakul'skaya Galina F. Myachina Konstantin B. Petrushenko 《Synthetic Metals》2010,160(13-14):1539-1543
Cationic polymerization of N-vinyl-2-phenylpyrrole (catalysts: Me3SiCl, CF3COOH, BF3·OEt2, HCl, WCl6, FeCl3, complex LiBF4–dimethoxyethane, catalysts concentration 1–2 wt%, 20–70 °C, 24–48 h) affords oligomers (molecular weight 1400–1700) of a unexpected structure with alternating 2-phenylpyrrole and ethylydene units, the yields reaching 63%. The oligomers structure has been supported by isolation and identification of the corresponding dimer, N-vinyl-2-phenyl-5-[N-(2-phenyl-1H-pyrrol-1-yl)ethyl]-1H-pyrrole. Radical polymerization of the same monomer (AIBN, 1.5–4 wt%, 60–80 °C, 40–60 h or UV irradiation or both) gives oligomers (molecular weight 2100–3000) of normal structure having polyethene backbone with pendant 2-phenylpyrrole groups in up to 40% yields. The oligomers of both types are semiconductors (1.3 × 10?6–3.6 × 10?6 S/cm) after doping with I2, paramagnetic (4.2 × 1017–8.7 × 1017 g?1) and fluorescent in a near UV region (λ 355–363 nm, acetonitrile). 相似文献
998.
Fulvio ArdenteAuthor Vitae Marco BeccaliAuthor VitaeMaurizio CelluraAuthor Vitae Marina Mistretta 《Energy and Buildings》2008,40(1):1-10
The paper presents a life cycle assessment of a kenaf-fibre insulation board following the international standards of the ISO 14040 series. Each life-cycle step has been checked, from kenaf production and board manufacture by an Italian firm, to use and disposal. 相似文献
999.
Phuong Hoai HaAuthor Vitae Marina PapatriantafilouAuthor VitaePhilippas Tsigas 《Journal of Parallel and Distributed Computing》2007
Reactive diffracting trees are efficient distributed objects that support synchronization, by distributing sets of memory accesses to different memory banks in a coordinated manner. They adjust their size in order to retain their efficiency in the presence of different contention levels. Their adjustment is sensitive to parameters that have to be manually determined after experimentation. Since these parameters depend on the application as well as on the system configuration and load, determining their optimal values is difficult in practice. Moreover, the adjustments are done one level at a time, hence the cost of multi-level adjustments can be high. 相似文献
1000.
SM Gaini EP Sganzerla L Fiori R Marina G Citerio 《Canadian Metallurgical Quarterly》1998,64(4):177-179
The examination of deaths due to electricity may require a comparison between current marks on the body and the electrodes suspected to have caused them. Normally the identification of the responsible electrode is carried out by analysing metal traces on the current marks. We however examined the conductor for traces of biological material after experimentally produced current marks. The surfaces of the conductors were investigated using a low-power macroscope and burnt tissue could always be recognised. Subsequently, all electrodes were carefully swabbed, extracted with chelex and typed for short tandem repeat polymorphisms using PCR. This procedure was successful in all cases. Therefore, DNA analysis can be a powerful tool to supplement conventional scene reconstruction in cases of deaths due to electricity. 相似文献