Search results for "PV"

Non-oxidative dehydroaromatization of methane:an effective reaction regeneration cyclic operation for catalyst life extension

2015

[EN] Non-oxidative methane aromatization is an attractive direct route for producing higher hydrocarbons. It is highly selective to benzene despite the low conversion due to thermodynamic limitations, and Mo/H-ZSM-5, the first catalyst proposed for this reaction, is still considered as one of the most adequate. The major problem of this process is the severe catalyst deactivation due to the rapid build-up of carbonaceous deposits on the catalysts. Here we present an effective regeneration procedure that extends the life of Mo/zeolite based catalysts by combining reaction periods of 1.5 h with 0.5 h regeneration steps in a continuous cyclic mode and methane activation after each regeneration…

Polypyrrole–palladium nanoparticles composite as efficient catalyst for Suzuki–Miyaura coupling

2012

International audience; Synthesis of a new hybrid material (Pd/PPy) composed of polypyrrole globules with uniformly incorporated Pd nanoparticles via direct redox reaction between pyrrole and Pd(NH3)(4)Cl-2 in water has been recently reported (V.A. Zinovyeva, M.A.Vorotyntsev, I. Bezverkhyy, D. Chaumont, J.-C. Hierso, Adv. Funct. Mater. 21 (2011) 1064-1075). In the actual study, this procedure has been extended to synthesize a series of Pd/PPy powders with variable palladium content and morphological parameters. Depending on the monomer-to-oxidant ratio in reaction mixture, average diameters of Pd and PPy particles may change in the ranges of 1.25-1.45 and 27-62 nm, respectively, the Pd conc…

A Finite Difference Model of a PV-PCM System

2012

Abstract The performances of a photovoltaic panel (PV) are defined according to the “peak power” that identifies the maximum electric power supplied by the panel when it receives an insolation of 1 kW/m2 and the temperature of the cell is maintained at 25 °C. These conditions are only nominal since the solar radiation has a variable intensity and also the panel is subjected to thermal excursions; due to these reasons the real power efficiency of the panel is considerably lower than that obtainable in the nominal conditions. The study focused on assessing a method to reduce the peak temperatures of PV systems using Phase Change Materials (PCM). To this aim it was created a numerical model ca…

Glycemic Outcome Associated With Insulin Pump and Glucose Sensor Use in Children and Adolescents With Type 1 Diabetes. Data From the International Pe…

2021

OBJECTIVE Insulin delivery methods, glucose-monitoring modalities, and related outcomes were examined in a large, international, diverse cohort of children and adolescents with type 1 diabetes from the Better Control in Pediatric and Adolescent Diabetes: Working to Create Centers of Reference (SWEET) -Registry. RESEARCH DESIGN AND METHODS Participants with type 1 diabetes of >= 1 year, aged <= 18 years, and who had documented pump or sensor usage during the period August 2017-July 2019 were stratified into four categories: injections-no sensor (referent); injections + sensor; pump-no sensor; and pump + sensor. HbA(1c) and proportion of patients with diabetic ketoacidosis (DKA) or severe hyp…

A case report of pulmonary vein isolation performed in a patient with polysplenia and interrupted inferior vena cava

2021

Abstract Background Pulmonary vein isolation (PVI) has entrenched itself as one of the main approaches for the treatment of paroxysmal symptomatic atrial fibrillation (AF). Pulmonary vein isolation prevents focal triggers from pulmonary veins from initiating AF paroxysms. As standard—PVI is performed through the inferior vena cava (IVC) approach, through the femoral vein. However, there are conditions when this approach is not appropriate or is not available. Case summary We report a case of a 53-year-old male who was referred to Pauls Stradins Clinical University Hospital for PVI due to worsening AF. Due to the rare anatomical variant of the venous system, the standard approach to PVI coul…

INTIMATE PARTNER VIOLENCE: PERCEPTION AND REPRESENTATION OF VIOLENCE AGAINST WOMEN IN GUANAJUATO. A QUALITATIVE RESEARCH

Intimate partner violence and domestic violence refer to the violation of women’s rights, often provoked by socio-cultural norms based on a patriarchal matrix. In Mexican society, in particular, gender-based violence affects the physical and psychological well-being of Mexican women. Moreover, the social representations of women who suffer violence and the lack of an effective legislative framework often reproduce the legitimation of gender-based violence, enhancing negative stereotypes and prejudices. In this scenario, the voice of the women who suffer violence in intimate relationships is silenced. In particular, in public and academic debates the impact and consequences of violence again…

A backward sweep method for power flow solution in distribution networks

2010

Abstract A methodology for the analysis of radial or weakly meshed distribution systems supplying voltage dependent loads is here developed. The solution process is iterative and, at each step, loads are simulated by means of impedances. Therefore, at each iteration, it is necessary to solve a network made up only of impedances; for this kind of network, all the voltages and currents can be expressed as linear functions of a single unknown current (in radial systems) or of two unknown currents for each independent mesh (for meshed systems). The methodology has been called “backward” since the unique equation, in case of radial network, and the linear system of equations, in case of meshed n…

Alma Mater: 2011/Rudens

2011

Universitātes Avīze : Alma Mater / LU Preses centrs ; LU Akadēmiskais apgāds. - Rudens (2011), 32.lpp.

Akadēmiķa Jāņa Endzelīna 149. dzimšanas dienas atceres starptautiskā zinātniskā konference "Valodas reģionālie varianti": tēzes, 2022. gada 22.–23. f…

2022

Tēžu krājumā apvienotas LU Latviešu valodas institūta rīkotās akadēmiķa Jāņa Endzelīna (1873–1961) 149. dzimšanas dienas atcerei veltītās starptautiskās zinātniskās konferences tēzes, kuras iesnieguši 36 konferences dalībnieki no Latvijas, Lietuvas un Polijas. Akadēmiķa atceres konferences tiek rīkotas jau kopš 1963. gada. 2022. gada 22.–23. februāra konference “Valodas reģionālie varianti” tika veltīta dialektoloģijai. Konferences tēžu krājums ietver pētījumus par dialektiem, izloksnēm un valodas paveidiem – valodu, ko runā pagastos, novados un plašākos reģionos. The collection of abstracts comprises 33 summaries of papers presented in the International Scientific Conference „Regional Vari…

Kriminālatbildība par izvairīšanos no pievienotās vērtības nodokļu nomaksas

2016

Maģistra darba tēma ir „Kriminālatbildība par izvairīšanos no pievienotās vērtības nodokļa nomaksas”. Darba mērķis ir veikt noziedzīgā nodarījuma par izvairīšanos no PVN nomaksas juridisko analīzi, un uz tās pamata izdarīt secinājumus un sniegt priekšlikumus pētāmā jautājuma kontekstā. Maģistra darbā ir pētītas nozieguma par izvairīšanos no PVN nomaksas objektīvās un subjektīvās pazīmes, kā arī analizētas ārvalsts tiesību aktos iekļautās normas, kurās paredzēta kriminālatbildība par izvairīšanos no PVN nomaksas. Maģistra darba kopsavilkumā, pamatojoties uz veikto pētījumu, darba autors aizstāvēšanai izvirza 10 tēzes. Nozīmīgākā no tēzēm ietver piedāvājumu nošķirt noziedzīgā nodarījuma – izv…