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111.
112.
Samples of soil from agricultural land around the industrial district of the city of Bari in Apulia and from rural areas of that region were analyzed, by atomic absorption spectrophotometry, for levels of As, Bi, Cd, Cu, Hg, Mn, Ni, Pb, Se, Sn, and Zn.All elements, except Se, were present in all samples from the industrial district, whereas Hg was not detectable in the rural soils; Bi, Cd, and Sn were found only in 50–60% of them. The average levels of Hg, Cd, Cu, Mn, and Ni in soils close to the industrial area always appeared to be higher than the mean levels in rural soils and the common ranges known for world soils.The findings suggest the existence of a metal contamination of soils in the industrial area. 相似文献
113.
This paper deals with the design of car bodies from the first sketches to the master model, ie to the last stage before mass manufacture. Close scrutiny of the various steps needed in drawing, control and construction make it possible to determine which of them can be replaced by modern automatic procedures. 相似文献
114.
Gian Piero Gallerano Andrea Doria Marzia Germini Emilio Giovenale Giovanni Messina Ivan P. Spassovsky 《Journal of Infrared, Millimeter and Terahertz Waves》2009,30(12):1351-1361
Two Free Electron Laser sources have been developed at ENEA-Frascati for a variety of applications: A Compact Free Electron
Laser (C-FEL) that provides coherent radiation in the frequency range between 90 and 150 GHz Gallerano et al. (Infrared Phys. and Techn. 40:161, 1999), and a second source, FEL-CATS, which utilizes a peculiar radio-frequency structure to generate coherent emission in the
range 0.4 to 0.7 THz Doria et al. (Phys. Rev. Lett 93:264801, 2004). The high peak power of several kW in 15 to 50 ps pulses, makes these sources particularly suitable for the assessment of
exposure limits in biological systems and for long range detection. In this paper we present a phase-sensitive reflective
imaging device in the mm-wave and THz regions, which has proven to be a valuable tool in the biological Ramundo-Orlando et al. (Bioelectromagnetics 28:587–598, 2007), environmental Doria et al. (2005) and art conservation fields Gallerano et al. (2008). Different setups have been tested at different levels of spatial resolution to image objects from a few centimeter square
to larger sizes. Images have been compared to identify and characterize the contrast mechanism. 相似文献
115.
Jose Emilio Pardo Enrique Fernández Manuela Rubio Andrés Alvarruiz Gonzalo Luis Alonso 《European Journal of Lipid Science and Technology》2009,111(2):188-193
In this work, oil obtained from seeds of different red grape varieties, grown in the Autonomous Regions of Castilla‐La Mancha and Murcia (Spain), was characterized by determining physicochemical and sensory quality parameters, stability, and the composition in fatty acids and sterols. The physicochemical quality parameters (free acidity, peroxide index, K270 and wax) scored high (meaning low quality) compared with virgin olive oils, while the negative sensory attributes stood out over the positive ones. Therefore, the oil was not considered suitable for table use without undergoing a refining process. The samples showed high linoleic and low linolenic acid contents, while β‐sitosterol was the main sterol found. Drying grape seeds with hot air before extraction gave higher physicochemical quality, total phenolic content and stability, and lower wax content in comparison to air‐drying of seeds. The drying process affected the sterol composition but not the fatty acid composition. 相似文献
116.
Gabriel Garcerá Raúl González‐Medina Emilio Figueres Jesús Sandia 《International Journal of Circuit Theory and Applications》2012,40(8):793-813
In photovoltaic (PV) double‐stage grid‐connected inverters a high‐frequency DC–DC isolation and voltage step‐up stage is commonly used between the panel and the grid‐connected inverter. This paper is focused on the modeling and control design of DC–DC converters with Peak Current mode Control (PCC) and an external control loop of the PV panel voltage, which works following a voltage reference provided by a maximum power point tracking (MPPT) algorithm. In the proposed overall control structure the output voltage of the DC–DC converter is regulated by the grid‐connected inverter. Therefore, the inverter may be considered as a constant voltage load for the development of the small‐signal model of the DC–DC converter, whereas the PV panel is considered as a negative resistance. The sensitivity of the control loops to variations of the power extracted from the PV panel and of its voltage is studied. The theoretical analysis is corroborated by frequency response measurements on a 230 W experimental inverter working from a single PV panel. The inverter is based on a Flyback DC–DC converter operating in discontinuous conduction mode (DCM) followed by a PWM full‐bridge single‐phase inverter. The time response of the whole system (DC–DC + inverter) is also shown to validate the concept. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
117.
Erick Scheuermann Ivette Seguel Adolfo Montenegro Rubn O Bustos Emilio Hormazbal Andrs Quiroz 《Journal of the science of food and agriculture》2008,88(3):485-492
BACKGROUND: ‘Murtilla’, ‘mutilla’ or ‘murta’ (Ugni molinae Turcz) is a native Chilean species that produces a small berry fruit with a special aroma, whose volatile compounds have not yet been identified. The fruit may be consumed raw and also as jams, juice, canned products, confections and liquor. RESULTS: At the beginning and end of the storage, 24 volatile compounds were identified in murtilla fruit aroma and the concentration of these compounds in murtilla fruit ranged from 1.2 to 250.5 µg kg?1 fresh weight. Methyl 2‐methyl butanoate, ethyl butanoate, ethyl 2‐methyl butanoate, methyl hexanoate, ethyl hexanoate, methyl benzoate and ethyl benzoate were the major components, all of which have been reported as potent odors in other aromatic fruits. Based on estimated odor activity value, the most potent compound in the murtilla fruit aroma were ethyl hexanoate and 4‐methoxy‐2,5‐dimethyl‐furan‐3‐one. The statistical analysis showed that the storage produced a distinct effect on the same volatile compounds released from the murtilla ecotypes. CONCLUSION: The volatile compounds identified in murtilla fruit aroma, which may be described as fruity, sweet and floral, have been found in other aromatic fruits. Concerning the aroma, the murtilla fruit from ecotype 19‐1 was shown to be the best in cooled storage. Copyright © 2007 Society of Chemical Industry 相似文献
118.
Prof. Dr. Arun K. Ghosh Dr. Margherita Brindisi Dr. Yu-Chen Yen Emma K. Lendy Dr. Satish Kovela Emilio Leal Cárdenas Dr. Bhavanam Sekhara Reddy Dr. Kalapala Venketeswara Rao Deborah Downs Dr. Xiangping Huang Dr. Jordan Tang Prof. Dr. Andrew D. Mesecar 《ChemMedChem》2019,14(5):545-560
Herein we present the design, synthesis, and biological evaluation of potent and highly selective β-secretase 2 (memapsin 1, beta-site amyloid precursor protein cleaving enzyme 2, or BACE 2) inhibitors. BACE2 has been recognized as an exciting new target for type 2 diabetes. The X-ray structure of BACE1 bound to inhibitor 2 a {N3-[(1S,2R)-1-benzyl-2-hydroxy-3-[[(1S,2S)-2-hydroxy-1-(isobutylcarbamoyl)propyl]amino]propyl]-5-[methyl(methylsulfonyl)amino]-N1-[(1R)-1-phenylpropyl]benzene-1,3-dicarboxamide} containing a hydroxyethylamine isostere was determined. Based on this structure, a computational docking study was performed which led to inhibitor 2 a -bound BACE2 models. These were used to optimize the potency and selectivity of inhibitors. A systematic structure–activity relationship study led to the identification of determinants of the inhibitors’ potency and selectivity toward the BACE2 enzyme. Inhibitors 2 d [N3-[(1S,2R)-1-benzyl-2-hydroxy-3-[[(1S,2S)-2-hydroxy-1-(isobutylcarbamoyl)pentyl]amino]propyl]-N1-methyl-N1-[(1R)-1-phenylpropyl]benzene-1,3-dicarboxamide; Ki=0.031 nm , selectivity over BACE1: ≈174 000-fold] and 3 l [N1-((2S,3R)-3-hydroxy-1-phenyl-4-((3-(trifluoromethyl)benzyl)amino)butan-2-yl)-N3,5-dimethyl-N3-((R)-1-phenylethyl)isophthalamide; Ki=1.6 nm , selectivity over BACE1: >500-fold] displayed outstanding potency and selectivity. Inhibitor 3 l is nonpeptide in nature and may pave the way to the development of a new class of potent and selective BACE2 inhibitors with clinical potential. 相似文献
119.
Victor H. Pino-Ramos Gerardo Cedillo Eduardo López-Barriguete Emilio Bucio 《应用聚合物科学杂志》2019,136(44):48170
Hydrophilic biocompatible surfaces can be obtained by grafting stimuli-sensitive polymers onto commercially available medical devices. Thermo and pH-responsive polymers are two of the most studied materials due to their potential application as drug delivery systems. Poly(N-vinylcaprolactam) has a lower critical solution temperature (LCST) near to physiological temperature. However, when it is grafted with pH-sensitive moieties its LCST it is affected undergoing remarkable displacements. We studied the effect of acrylic acid (AAc), 4-vinylpyridine (4VP), and 1-vinylimidazole (Vim) on the LCST of N-vinylcaprolactam (NVCL) grafted onto silicone rubber (SR), and SR-g-NVCL (32.5 °C). The binary graft copolymers were obtained by ionizing grafting radiation using the simultaneous technique; the samples were characterized by Fourier transform infrared attenuated total reflectance (FTIR-ATR), cross-polarization magic angle spinning nuclear magnetic resonance (CP/MAS 13C-NMR), and thermogravimetrical analysis (TGA). LCST value was dramatically affected by the comonomer content; even it was observed the switching from LCST to upper critical solution temperature (UCST) for (SR-g-NVCL)-g-AAc and (SR-g-NVCL)-g-4VP samples. The observed behavior is rarely reported for binary graft copolymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48170. 相似文献