Search results for "NIR"

From the memory of the experience to the relationship with the retailer : a theoretical and methodological exploration in the field of retail

2015

Our research proposes an enrichment of the experiential paradigm by focusing on the consequences of experience. We support the view that an approach by the memory of the experience can partly compensate for the limitations of satisfaction in understanding the retailer-customer relationship. Our literature review leads us to a better understanding of the relationship between experience, memory of the experience and remembered experience. The completion of two longitudinal studies helps to: [1]. conceptualize dimensions of the memory of the shopping experience; [2]. understand the evolution of memory over time; [2]. study its effects on satisfaction, retailer attitude, retailer commitment, an…

Upconversion Nanoparticles for Bioimaging and Regenerative Medicine.

2016

Nanomaterials are proving useful for regenerative medicine in combination with stem cell therapy. Nanoparticles can be administrated and targeted to desired tissues or organs and subsequently, be used in non-invasive real-time visualization and tracking of cells by means of different imaging techniques, they can act as therapeutic agent nanocarriers, and can also serve as scaffolds to guide the growth of new tissue. Nanoparticles can be of different chemical nature, such as gold, iron oxide, cadmium selenide, and carbon, and have the potential to be used in regenerative medicine. However, there are still many issues to be solved, such as toxicity, stability, and resident time. Upconversion …

Optical studies of Y3(Al,Ga)5O12:Ce3+,Cr3+,Nd3+ nano-phosphors obtained by the Pechini method

2019

The Y-3(Al,Ga)(5)O-12:Ce3+,Cr3+,Nd3+ (YAGG) nano-phosphors with homogeneous particle-size distribution, low aggregation and average crystalline size of about 65 nm were obtained using a modified Pechini method. Only slight aggregation of the crystallites occurs after post-annealing at 1100 degrees C. The intense Ce3+ bands in the excitation spectra of the Ce3+,Cr3+,Nd3+ co-doped materials monitoring the Cr3+ emission at 690 nm indicate energy transfer from Ce(3+ )to Cr3+. Weak Nd3+ lines are observed, as well. In addition, the emission of Nd3+ at 1060 nm with excitation of Ce3+ and Cr3+ confirms the Ce3+/Cr3+ to Nd3+ energy transfer. The short average luminescence decay times for the Ce3+ e…

Functional gene pyrosequencing reveals core proteobacterial denitrifiers in boreal lakes

2015

Denitrification is an important microbial process in aquatic ecosystems that can reduce the effects of eutrophication. Here, quantification and pyrosequencing of nirS, nirK, and nosZ genes encoding for nitrite and nitrous oxide reductases was performed in sediment samples from four boreal lakes to determine the structure and seasonal stability of denitrifying microbial populations. Sediment quality and nitrate concentrations were linked to the quantity and diversity of denitrification genes, the abundance of denitrifying populations (nirS and nosZ genes) correlated with coupled nitrificationdenitrification (Dn), and the denitrification of the overlying water NO3 − (Dw) correlated with the n…

Recent Advances in Enantioselective Desymmetrizations of Prochiral Oxetanes

2021

Abstract Strain relief of oxetanes offers a plethora of opportunities for the synthesis of chiral alcohols and ethers. In this context, enantioselective desymmetrization has been identified as a powerful tool to construct molecular complexity and this has led to the development of elegant strategies on the basis of transition metal, Lewis acid, and Brønsted acid catalysis. This review highlights recent examples that harness the inherent reactivity of prochiral oxetanes and offers an outlook on the immense possibilities for synthetic application.

N-Heterocyclic Carbenes with Inorganic Backbones: Electronic Structures and Ligand Properties

2008

The electronic structures of known N-heterocyclic carbenes (NHCs) with boron, nitrogen, and phosphorus backbones are examined using quantum chemical methods and compared to the experimental results and to the computational data obtained for a classical carbon analogue, imidazol-2-ylidene. The σ-donor and π-acceptor abilities of the studied NHCs in selected transition-metal complexes are evaluated using a variety of approaches such as energy and charge decomposition analysis, as well as calculated acidity constants and carbonyl stretching frequencies. The study shows that the introduction of selected heteroatoms into the NHC backbone generally leads to stronger metal−carbene bonds and theref…

Electronic Structures of Main-Group Carbene Analogues

2007

The electronic structures of 15 group 13−16 carbene analogues are analyzed using various quantum chemical methods and compared to the data obtained for the parent N-heterocyclic carbene (NHC), imidazol-2-ylidene. The results of this study present a uniform analysis of the similarities and differences in the electronic structures of p-block main-group carbene analogues. Though all systems are formally isovalent, the theoretical analyses unambiguously indicate that their electronic structures run the gamut from CC localized (group 13) to CN localized (group 16) via intermediate, more delocalized, systems. In particular, neither the stibenium ion nor any of the chalcogenium dications is a dire…

Temperature dependence of O2 singlet photoluminescence in silica nanoparticles

2012

Cerebrālā oksimetrija pie pleca endoprotezēšanas operācijām

2022

Ievads: Deģeneratīvas plecu locītavu slimības skar gados vecākus cilvēkus. Jaunākās ortopēdiskās ķirurģijas metodes piedāvā jaunus risinājumus. Plecu locītavas protezēšanas operācijas laikā pacients pozicionēts pussēdus stāvoklī. Ir ziņojumi par gan pārejošiem, gan pastāvīgiem neiroloģiskiem bojājumiem pēc pleca locītavas operācijas. Autora mērķis noteikt pacientiem reģionālas galvas smadzeņu desaturācijas epizodes (CDE) pie plecu endoprotezēšanas operācijām vispārējā anestēzijā un iespējamo saistību ar neiroloģiskām komplikācijām. Metodes: Monocentrisks, prospektīvais novērošanas pētījums tika veikts Traumatoloģijas un ortopēdijas slimnīcā. 24 pacientu grupa saņēma kombinētu pleca pinuma b…

Low-Temperature Miniemulsion-Based Routes for Synthesis of Metal Oxides.

2020

Abstract The use of miniemulsions containing chemical precursors in the disperse phase is a versatile method to produce nanoparticles and nanostructures of different chemical nature, including not only polymers, but also a variety of inorganic materials. This Minireview focuses on materials in which nanostructures of metal oxides are synthesized in processes that involve the miniemulsion technique in any of the steps. This includes in the first place those approaches in which the spaces provided by nanodroplets are directly used to confine precipitation reactions that lead eventually to oxides. On the other hand, miniemulsions can also be used to form functionalized polymer nanoparticles th…