Search results for "amp"

Ferro-pedrizite, NaLi2(Fe2+ 2Al2Li)Si8O22(OH)2, a new amphibole-supergroup mineral from the Sutlug pegmatite, Tyva Republic, Russia

2015

Ferro-pedrizite, a new amphibole-supergroup mineral was discovered in the Sutlug pegmatite occurrence situated in the Targi River Basin, Tyva Republic, Eastern Sibera, Russia. The associated minerals are quartz, albite, microcline, spodumene, cassiterite, beryl, columbite-(Mn), fergusonite-β-(Y), fluorapatite, schorl, trilithionite and fluorite. Ferro-pedrizite forms dark grey-blue to violet-blue acicular and long prismatic crystals up to 2 × 5 × 50 mm and their aggregates. D meas = 3.16(1) g/cm3 (by hydrostatic weighing), 3.13(1) g/cm3 (by flotation in heavy liquids); D calc = 3.135 g/cm3. Ferro-pedrizite is optically biaxial (−), α = 1.614(3), β = 1.638(3), γ = 1.653(3), 2 V meas = 75(5)°…

Flame atomic absorption analysis of gold in jewelry samples

1990

A new procedure is proposed for the determination of gold by flame atomic absorption in jewelry samples. The method is based on the acid digestion of 10 mg of sample in a microwave oven and on the on-line dilution, using a three-way valve. The dynamic range of the technique is extended to 100 mg/l gold solutions and using a weighted bracketing method for the treatment of the results, accuracy errors lower than 2% can be found in the analysis of real samples as compared with those obtained by fire assay. The method is very fast and implies only little damage to the jewelry samples.

PROGETTAZIONE, SINTESI E CARATTERIZZAZIONE DI NUOVI DERIVATI POLISACCARIDICI E POLIURETANICI PER LA PRODUZIONE DI BIOMATERIALI INNOVATIVI PROCESSABIL…

2022

A Difficult Case of Necrotizing Fasciitis Caused By Acinetobacter baumannii

2010

This study reports the case of a 55-year-old woman with diabetes with a necrotizing fasciitis of the right lower limb and the perineum, first admitted at the emergency department for septic shock with cardiac arrest, and later transferred to the department of surgery. Microbiological and histopathological examination confirmed the diagnosis of necrotizing fasciitis caused by Acinetobacter baumanii. A broad-spectrum antibiotic therapy was administered and later readjusted according to the results of microbiological culture. Intensive hemodynamic support was required. Wounds were dressed daily with a 3 percent boric acid solution and a silver sulfadiazine-impregnated dressing. An extensive s…

Measurement of acoustic attenuation in South Pole ice

2010

Using the South Pole Acoustic Test Setup (SPATS) and a retrievable transmitter deployed in holes drilled for the IceCube experiment, we have measured the attenuation of acoustic signals by South Pole ice at depths between 190 m and 500 m. Three data sets, using different acoustic sources, have been analyzed and give consistent results. The method with the smallest systematic uncertainties yields an amplitude attenuation coefficient alpha = 3.20 \pm 0.57 km^(-1) between 10 and 30 kHz, considerably larger than previous theoretical estimates. Expressed as an attenuation length, the analyses give a consistent result for lambda = 1/alpha of ~1/300 m with 20% uncertainty. No significant depth or …

Complex power distribution analysis in plates covered with passive constrained layer damping patches

2012

International audience; The vibration of a plate partially covered with a passive constrained layer damping (PCLD) patch is studied from an energetic point of view. The damped plate is excited by an acoustic plane wave. The study is done with a numerical two-dimensional multilayer plate model. Results of the present model are compared to those obtained with three-dimensional finite element models. It is shown that the present model gives accurate results, even for the layer's inner behavior. It is less expansive in terms of computational cost; hence, it can simulate efficiently the structure for higher frequencies. Mathematical formulas for complex mechanical power are presented, and the li…

Estimation of fibre orientation from digital images

2001

In this paper, estimation of fibre orientation is studied for fibre systems observable as a blurred greyscale image. The estimation method is based on scaled variograms observed along a set of sampling lines in different directions. The parameters of the orientation distribution are obtained numerically. Simulated data are used to study the statistical properties of the method.

Subjective ranking of concert halls substantiated through orthogonal objective parameters.

2015

[EN] This paper studies the global subjective assessment, obtained from mean values of the results of surveys addressed to members of the audience of live concerts in Spanish auditoriums, through the mean values of the three orthogonal objective parameters (Tmid, IACCE3, and LEV), expressed in just noticeable differences (JNDs), regarding the best-valued hall. Results show that a linear combination of the relative variations of orthogonal parameters can largely explain the overall perceived quality of the sample. However, the mean values of certain orthogonal parameters are not representative, which shows that an alternative approach to the problem is necessary. Various possibilities are pr…

Acoustic monitoring of the artificial airway — experimental results

1997

Non-invasive acoustic airway-monitoring was evaluated in an experimental study. Recording amplitude and travel time of acoustic pulse response, an acoustic pattern of airway's geometry was then calculated. Measurements on models and excised human cadaver lungs were performed to discover whether displacement or obstruction of the artificial airway could be detected by its acoustic equivalent. Regression analysis revealed a close correlation between displacement of tracheostomy tubes and the shifting of the acoustic area-distance function (corr. coeff.: 0.97-1) and an adequate correlation between acoustic and planimetrical determination of cross-sectional area within the tubes (corr. coeff.: …

Development of a sensitive method for the determination of acrylamide in coffee using high-performance liquid chromatography coupled to a hybrid quad…

2015

The emerging trend towards high-resolution mass spectrometry (MS) alternatives was evaluated by the application of Orbitrap MS for the determination of acrylamide in coffee samples. The high resolving power of the Orbitrap MS provided the high selectivity and sensitivity that enabled quantitative analysis of acrylamide in complex matrices, such as coffee. Several sample preparation methods and scanning modes of the MS (full MS, t-SIM, t-MS2) were assessed in order to optimise parameters of the analytical method. The final procedure involved the extraction of acrylamide with acetonitrile, solid-phase extraction with dispersive primary secondary amine (PSA) and amino columns, and the detectio…