Search results for "second"
showing 10 items of 3671 documents
Effects of NH3 and alkaline metals on the formation of particulate sulfate and nitrate in wintertime Beijing
2020
Sulfate and nitrate from secondary reactions remain as the most abundant inorganic species in atmospheric particle matter (PM). Their formation is initiated by oxidation (either in gas phase or particle phase), followed by neutralization reaction primarily by NH3, or by other alkaline species such as alkaline metal ions if available. The different roles of NH3 and metal ions in neutralizing H2SO4 or HNO3, however, are seldom investigated. Here we conducted semi-continuous measurements of SO4 2−, NO3 −, NH4 +, and their gaseous precursors, as well as alkaline metal ions (Na+, K+, Ca2+, and Mg2+) in wintertime Beijing. Analysis of aerosol acidity (estimated from a thermodynamic model) indicat…
Study by static SIMS, XPS and UPS of the adsorption of cyanogen on (100) Ni surfaces
2000
Abstract The interaction of cyanogen with (100) Ni surfaces at room temperature was studied using secondary ion mass spectrometry in a static mode, and photoemission spectroscopies (XPS and UPS). It has been shown that cyanogen is adsorbed on this nickel surface in a dissociative mode: atomic carbon and nitrogen are present on the surface as well as CN fragments. These adsorbed species have been characterized by XPS and UPS. Increasing the temperature in the 400 K range increases the rate of the dissociation reaction of CN into atomic carbon and nitrogen. Moreover carbon is found to dissolved into the bulk for temperatures as low as 475 K. No evidence has been found of a polymerized form of…
Trace Analysis of Plutonium and Technetium by Resonance Ionization Mass Spectrometry Using an Atomic Beam and a Laser Ion Source
1990
A method for low level detection of plutonium and technetium is described with a detection limit of less than 107 atoms. Plutonium is a very toxic element due to its radioactive decay as well as its chemical behaviour. It was released to the environment in large amounts during the fifties and sixties of his century, principally by nuclear-weapon tests and some accidents. As a result about 0.4 − 4 mBq per gram 239Pu(T1/2 = 24390 y), corresponding to 4 × 108 − 4 × 109 atoms, can be found in the Northern Hemisphere in soil samples.
Octave Spanning Supercontinuum in Titanium Dioxide Waveguides
2018
International audience; We report on the experimental generation of an octave-spanning supercontinuum in a 2.2 cm-long titanium dioxide optical waveguide with two zero dispersion wavelengths. The resulting on-chip supercontinuum reaches the visible wavelength range as well as the mid-infrared region by using a femtosecond fiber laser pump at 1.64 µm.
Promuovere la convivenza e la cittadinanza: nascita di un centro di aggregazione giovanile interculturale
2012
Il contributo descrive ed analizza i principali steps da compiere per progettare un Centro di Aggregazione Interculturale. Vengono mostrati aspetti di contenuto e procedure principali con l'illustrazione parallela di un Centro realmente esistente a Palermo. Si privilegiano aspetti pragmatici e l'idea della co-progettazione partecipata.
Język Kościoła posoborowego
2017
Drugi Sobór Watykański przyniósł Kościołowi katolickiemu wiele zmian, co zaowocowało także istotnymi przeobrażeniami języka. Niniejszy artykuł koncentruje się na zjawiskach, jakie zaszły w języku wskutek zmiany stosunku Kościoła do świata zewnętrznego, a w szczególności do trzech kategorii niekatolików, czyli do chrześcijan innych wyznań, wyznawców innych religii oraz ludzi niewierzących. Język Kościoła przedpoborowego bardziej służył konfrontacji i obronie niż merytorycznemu nauczaniu. O tonie dyskursu przesądzało wówczas przekonanie, że niekatolicy są dla katolików przede wszystkim zagrożeniem, przed którym Kościół musi ich bronić. Posoborowe zmiany na płaszczyźnie języka mają charakter r…
Incidence and Management of Recurrence in Patients with Crohn's Disease Who Have Undergone Intestinal Resection: The Practicrohn Study.
2017
Background: More than 50% of patients with Crohn's disease require intestinal resection at least once. Postoperative recurrence (POR) is almost uniform if prophylactic treatment is not started early. Endoscopic monitoring is generally advised. We studied the incidence and management of recurrence in patients who had undergone intestinal resection. Methods: Practicrohn was an observational retrospective study performed in 26 Spanish hospitals including patients aged >= 18 years who underwent Crohn's disease-related ileocolonic resection between January 2007 and December 2010. We recorded preventive treatments, the incidence of clinical recurrence in daily practice, and associated risk factor…
Pitch contours in Russian yes/no questions by Finns
2010
The aim of this paper is to determine the pitch contours Finns use when uttering yes/no questions in Russian. In addition, the pitch contours will be compared to native speech as well as subjected to native speaker evaluation. So far, there has been very little research on the prosody of Russian as a second language. L1 Finnish students are an interesting group to study because intonation in Finnish is not distinctive whereas in Russian it is. peerReviewed
How do native speakers of Russian evaluate yes/no questions produced by Finnish L2 learners?
2010
This study analyzes native Russian speakers’ evaluation of seven Russian yes/noquestions each produced by Finnish speakers in two sets of recordings (during a stay in Russia and after it). The Finnish speakers were six female university students of Russian. This research question is interesting because the two typologically unrelated languages differ in the prosody of yes/no-questions. In Russian a yes/no-question is created from a lexically and syntactically corresponding statement by means of intonation, whereas in Finnish the cue for questioning is an interrogative particle – ko/-kö instead of prosody. Hence, native Finnish speakers are likely to have difficulties in pronouncing Russian …