Search results for "reduction"
showing 10 items of 2058 documents
Synthesis of phosphine derivatives of [Fe2(CO)6(μ-sdt)] (sdt = SCH2SCH2S) and investigation of their proton reduction capabilities
2023
The reactions of [Fe2(CO)6(μ-sdt)] (1) (sdt = SCH2SCH2S) with phosphine ligands have been investigated. Treatment of 1 with dppm (bis(diphenylphosphino)methane) or dcpm (bis(dicyclohexylphosphino)methane) affords the diphosphine-bridged products [Fe2(CO)4(μ-sdt)(μ-dppm)] (2) and [Fe2(CO)4(μ-sdt)(μ-dcpm)] (3), respectively. The complex [Fe2(CO)4(μ-sdt)(κ2-dppv)] (4) with a chelating diphosphine was obtained by reacting 1 with dppv (cis-1,2-bis(diphenylphosphino)ethene). Reaction of 1 with dppe (1,2-bis(diphenylphosphino)ethane) produces [{Fe2(CO)4(μ-sdt)}2(μ-κ1-dppe)] (5) in which the diphosphine forms an intermolecular bridge between two diiron cluster fragments. Three products were obtaine…
Vizuālās informācijas ietekme uz sāpju slieksni.
2020
Maģistra darbs ir uzrakstīts angļu valodā uz 36 lapam. Tas satur 17 attēlus, 4 tabulas u 82 atsauces. Mērķis: Izpētīt, kā dažādas tematiskās fotogrāfijas modulē sāpju noteikšanas sliekšņus, un novērtētu emocionālās fotogrāfijas izmantojot pašnovērtējuma manekenu metodi (SAM). Metodes: 21 sievietei sāpju noteikšanas sliekšņi tika izmērīti ar pakāpeniski pieaugoša sprieguma padevi dalībnieku apakšdelmiem. Rezultāti: Sāpju noteikšanas sliekšņi tika samazināti ar negatīvām valences fotogrāfijām (attēlojot vardarbību, dzīvnieku un cilvēku uzbrukumus, zaudējumus). Skatoties neitrālās un pozitīvās fotogrāfijas, sāpju noteikšanas sliekšņi neatšķīrās. SAM pozitīvo fotogrāfiju vērtējumi atklāja augst…
Empīriskajā metodē izstrādāto aktivitāšu ietekme angļu valodas runātprasmes apguvei 11. klases skolēniem Rīgas tehnikumā
2019
Diplomdarbā tiek pētīts, kā empīriskajā metodē izstrādātās aktivitātes uzlabo skolēnu runas prasmes, samazina stresu un baiļu sajūtu no runāšanas. Mērķis ir izstrādāt uz empīrisko metodi balstītas apmācību aktivitātes un izpētīt, kā tas veicina skolnieku runas prasmju attīstīšanu un vai motivē aktīvi piedalīties apmācības procesā. Teorētiskajā daļā ir pētīta runas prasme, empīriskās apmācības teorija un tās pielietošana apmācībās procesā. Empīriskajā daļā atspoguļoti metodes pielietošanas rezultāti. Sākotnējās pārbaudes rezultātu analīze, salīdzinot ar starppārbaudes un gala pārbaudes rezultātiem, pierādīja, ka skolnieku grupai, kuri bija iesaistīti eksperimentā, uzlabojās runas prasme, sam…
A parallel radix-4 block cyclic reduction algorithm
2014
A conventional block cyclic reduction algorithm operates by halving the size of the linear system at each reduction step, that is, the algorithm is a radix-2 method. An algorithm analogous to the block cyclic reduction known as the radix-q partial solution variant of the cyclic reduction (PSCR) method allows the use of higher radix numbers and is thus more suitable for parallel architectures as it requires fever reduction steps. This paper presents an alternative and more intuitive way of deriving a radix-4 block cyclic reduction method for systems with a coefficient matrix of the form tridiag{ − I,D, − I}. This is performed by modifying an existing radix-2 block cyclic reduction method. Th…
Revisiting the Solid Flux Theory
2022
Several variations of the basic activated sludge process and of the related design procedures for final clarifiers have been developed, which are frequently based on the well-known solid flux theory (SFT). In this paper, by using the Lambert W function and a “virtual” solid flux corresponding to the Vesilind parameters’ ratio, the SFT is reformulated, and dimensionless groups are detected, which highly reduce the number of parameters that are involved in the final clarifiers’ design procedure. The derived dimensionless relationships and the corresponding plots have general validity since they can be applied to all the possible design/verification parameter combinatio…
MR3104897 Reviewed Mawhin, J. Variations on some finite-dimensional fixed-point theorems. Translation of Ukraïn. Mat. Zh. 65 (2013), no. 2, 266–272. …
2014
Inglese:The author presents an interesting discussion on three fundamental results in the literature and related theory: the Poincaré-Miranda theorem [C. Miranda, Boll. Un. Mat. Ital. (2) 3 (1940), 5–7; MR0004775 (3,60b)], the Pireddu-Zanolin fixed point theorem [M. Pireddu and F. Zanolin, Topol. Methods Nonlinear Anal. 30 (2007), no. 2, 279–319; MR2387829 (2009a:37032)] and the Zgliczyński fixed point theorem [P. Zgliczyński, Nonlinear Anal. 46 (2001), no. 7, Ser. A: Theory Methods, 1039–1062; MR1866738 (2002h:37032)]. The author provides generalizations of the last two fixed point theorems by using the original technique that he developed in a previous paper and the Poincaré-Miranda theor…
Effect of oxidoreduction potential and of gas bubbling on rheological properties and microstructure of acid skim milk gels acidified with glucono-del…
2009
Milk oxidoreduction potential was modified using gases during the production of a model dairy product and its effect on gel setting was studied. Acidification by glucono-delta-lactone was used to examine the physicochemistry of gelation and to avoid variations due to microorganisms sensitive to oxidoreduction potential. Four conditions of oxidoreduction potential were applied to milk: milk was gassed with air, nongassed, gassed with N(2), or gassed with N(2)H(2). The rheological properties and microstructure of these gels were determined using viscoelasticimetry, measurement of whey separation, and confocal laser scanning microscopy. It appeared that a reducing environment led to less-aggre…
New opportunities and perspectives of high pressure treatment to improve health and safety attributes of foods. A review
2015
Abstract High pressure (HP) treatment has emerged as a novel, additive-free food preservation technology. It has been scientifically and commercially proven that HP can produce microbially safe and stable products with improved quality characteristics such as enhanced flavor and color. Recent studies have focused on the effects of HP on health attributes and allergenic potential of foodstuff to develop the next generation of convenience foods. This review provides an overview on the current knowledge of HP treatment to improve the extraction and bioavailability of bioactive compounds, to reduce allergenicity, to retain essential fatty acids, to reduce the salt content, and to reduce formati…
To B or Not to B: Comparative Genomics Suggests
2018
Insect lineages feeding on nutritionally restricted diets such as phloem sap, xylem sap, or blood, were able to diversify by acquiring bacterial species that complement lacking nutrients. These bacteria, considered obligate/primary endosymbionts, share a long evolutionary history with their hosts. In some cases, however, these endosymbionts are not able to fulfill all of their host's nutritional requirements, driving the acquisition of additional symbiotic species. Phloem-feeding members of the insect family Aleyrodidae (whiteflies) established an obligate relationship with Candidatus Portiera aleyrodidarum, which provides its hots with essential amino acids and carotenoids. In addition, ma…
Modified total variation regularization using fuzzy complement for image denoising
2015
In this paper, we propose a denoising algorithm based on the Total Variation (TV) model. Specifically, we associate to the regularization term of the Rodin-Osher-Fatimi (ROF) functional a small weight whenever denoising is performed in edge and texture regions, which means less regularization and more details preservation. On the other hand, a large weight is associated if the region being filtered is smooth which means noise will be well suppressed. The weight computation is inspired from the fuzzy edge complement. Experiments on well-known images and comparison with state of the art denoising algorithms demonstrate that the proposed method not only presents good denoising performance but …