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101.
Carlo Beatrice Chiara Guido Pierpaolo Napolitano Silvana Di Iorio Nicola Del Giacomo 《Fuel》2011,90(5):2039-2044
Results of a research project aimed at studying the capability to develop a method (economic and simple) for on-board biodiesel blending detection are described. The method is based on the direct measurement of the Indicated Mean Effective Pressure (IMEP).The study was carried out on a 2.0L four-cylinder “torque-controlled” Euro 5 diesel engine for passenger car (PC) application. This engine, equipped with instrumented glow plug for combustion closed-loop control, represents the state of the art of the diesel engine control technology.Two biodiesels were chosen for the experiments: a rapeseed methyl-ester (RME) and an aged RME, while the conventional diesel fuel was an European (EU) certification diesel fuel.Results indicate generally a good response in blending detection of the method. However, in order to attain an acceptable accuracy, a pre-calibration appears necessary. 相似文献
102.
The input of a waveguide probe for shell eggs was connected to a sinewave sweeper oscillator and the signal at the output was captured by a spectrum analyser. A first analysis was carried out in the range from 3 to 20 GHz with a span of 1 GHz to investigate which 1 GHz frequency range contains most information for predicting the main quality indices of eggs during 15 days of storage. Simple linear regression models were therefore set up and the coefficient of determination was calculated. The absorbance spectra in the range thus identified (from 10.5 to 11.5 GHz) were used to predict the quality indices by means of an artificial neural network (ANN). The R2 values of the obtained ANN in validation mode were 0.918, 0.854 and 0.912 for the air cell, the thick albumen height and the yolk index, respectively. The correlations between the quality parameters and tests carried out on albumen, yolk and plastic eggs for simulating the air cell showed how one index can be indirectly predicted through another one. 相似文献
103.
104.
Paolo Sarti Maria Chiara Magnifico Fabio Altieri Daniela Mastronicola Marzia Arese 《International journal of molecular sciences》2013,14(6):11259-11276
Extending our previous observations, we have shown on HaCat cells that melatonin, at ~10−9 M concentration, transiently raises not only the expression of the neuronal nitric oxide synthase (nNOS) mRNA, but also the nNOS protein synthesis and the nitric oxide oxidation products, nitrite and nitrate. Interestingly, from the cell bioenergetic point of view, the activated NO-related chemistry induces a mild decrease of the oxidative phosphorylation (OXPHOS) efficiency, paralleled by a depression of the mitochondrial membrane potential. The OXPHOS depression is apparently balanced by glycolysis. The mitochondrial effects described have been detected only at nanomolar concentration of melatonin and within a time window of a few hours’ incubation; both findings compatible with the melatonin circadian cycle. 相似文献
105.
A critical review of the state of the art of research on internal forced convection boiling in microchannels and in microgravity conditions is the main object of the present paper. 相似文献
106.
Chiara Tognoli Marco Saroglia Genciana Terova Rosalba Gornati Giovanni Bernardini 《Food chemistry》2011
The 5S ribosomal RNA is a very suitable target for easy, rapid and inexpensive fish species identification due to its structure, consisting of a conserved region followed by a species-specific noncoding region called ‘nontranscribed spacer’. We have exploited this species-specificity in length and sequence to discriminate among fish species which can be subjected to substitution in the fish markets. After sequencing and alignment of the corresponding portions of the 5S rRNAs of different fish species, we have designed the primer pairs necessary for PCR amplification on the DNA traits which most diverged and a primer pair on conserved regions. Our results have shown the feasibility, simplicity and reliability of the proposed approach for the detection of mislabelling or fraudulent substitution of fish species. 相似文献
107.
Fabio Maria Sabbatini Dr. Romano Di Fabio Dr. Mauro Corsi Dr. Paolo Cavanni Dr. Steve M. Bromidge Dr. Yves St‐Denis Dr. Lucilla D'Adamo Dr. Marilisa Rinaldi Dr. Chiara Savoia Dr. Claudia Mundi Dr. Benedetta Perini Dr. Andrew J. Carpenter Dr. Giovanna Dal Forno Dr. Federico Faggioni Dr. Michela Tessari Dr. Francesca Pavone Dr. Alberto Buson Dr. Mario Mattioli Dr. Elisabetta Perdona' Dr. Sergio Melotto Dr. 《ChemMedChem》2010,5(9):1450-1455
108.
Vincenzo Calemma Chiara Gambaro Wallace O. Parker Rosa Carbone Roberto Giardino Pietro Scorletti 《Catalysis Today》2010,149(1-2):40-46
A light cobalt catalyzed Fischer–Tropsch (FT) wax was subjected to hydrocracking in the range of temperature 319–351 °C and hydrogen pressure between 3.5 and 6.0 MPa. The catalyst used was platinum on amorphous silica–alumina. Hydrocracking reaction led to an increase of middle distillate yield up to 85% with a contemporary increase of iso-paraffins concentration which resulted in a remarkable improvement of cold flow properties of the products. The freezing point of C10–C14 fraction passed from ?23 to ?45 °C while the pour point of C15–C22 fraction decreased from 13 to ?23 °C. The latter fraction displayed high cetane numbers ranging between 75 and 80. Changes in carbon distribution and molecular structure of products during hydrocracking have been rationalized in the light of the accepted hydrocracking mechanism where n-paraffins undergo to consecutive isomerization reactions leading to isomers with progressively higher branching degree and concomitant cracking reaction. Experimental evidences support the view that apparent reactivity of n-paraffins is chain length dependent, increasing with the molecular weight. Detailed characterization by NMR and GC showed that branching groups abundance in the middle distillate products was the following: methyl ? ethyl > propyl.Emission tests carried out with FT diesel and commercial ultra low sulfur diesel showed that FT diesel has excellent combustion properties and leads to a reduction of emissions. 相似文献
109.
Chiara Cavaliere Patrizia Foglia Chiara Guarino Mario Motto Manuela Nazzari Roberto Samperi Aldo Laganà Nicola Berardo 《Food chemistry》2007,105(2):700-710
A confirmatory method for fusariotoxin analysis in maize meal, based on liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS), was developed, and compared with a previously published screening method, based on the same technique. By eluting selectively from a Carbograph-4 clean-up cartridge trichothecenes, fumonisins and macrocyclic lactones, and optimizing LC–MS/MS conditions for every chemical class, a sensitive and reliable determination was performed. Method quantification limits for confirmatory and screening methods were in the range 0.001–0.019 mg/kg and 0.003–0.125 mg/kg, respectively. 相似文献
110.
M Barbero R Enria M Pagliano M Canni P Nicolaci U Bertini F Bocci C Bocci G Chiara 《Canadian Metallurgical Quarterly》1997,49(11):491-497
BACKGROUND: The aim of this study was to determine the diagnostic value of hysteroscopy and transvaginal ultrasonography in patients with abnormal uterine bleeding (AUB) in the peri and postmenopausal period. METHODS: 302 patients with AUB, underwent hysteroscopy and in 86 cases, also a transvaginal ultrasonography before hysteroscopy was performed. Results were compared with the histological diagnosis. RESULTS: The diagnostic accuracy of hysteroscopy was very high in the cases of endometrial carcinoma (sensibility 100%, specificity 99%), and lower in the cases of endometrial hyperplasia (sensibility 69%, specificity 72%) and endometrial atrophy (sensibility 29% and specificity 97%). Sonography proved to be less reliable in the diagnosis of endometrial pathology (carcinoma: sensibility 57%, specificity 100%, hyperplasia: sensibility 62.5% specificity 63%). The results of this study show that sonography may be used as a first choice diagnostic test in the investigation of women with AUB. CONCLUSIONS: Hysteroscopy represent a second diagnostic step for achieving a proper histologic diagnosis. 相似文献