Search results for "CEM"
showing 10 items of 3487 documents
La distribución de cerámica y materiales de construcción en España
2007
La caracterización de las empresas de un sector es esencial para com- prender la situación de la distribución comercial y analizar su evolución. En el presente trabajo abordamos el estudio de los distribuidores de material cerámico y de construcción en España a partir de fuentes de información primaria y secundaria. La lectura conjunta de los resultados obtenidos a par- tir de ambas fuentes de datos permite realizar una primera aproximación a la situación de un sector que ha experimentado un extraordinario crecimiento en los últimos años. Characterization of firms in a sector is essential to understand the situation of commercial distribution and monitor developments. In this paper we study…
Dynamic leach testing of low- and medium-pH injection grouts to be used in deep repositories : cementitious materials in deep geological repositories
2008
The use of bark of Scots Pine in environmental impact assessment of cement and lime dust
2016
Analizie poddano korę sosny zwyczajnej znajdującej się pod presją zanieczyszczeń alkalicznych cementowni Chełm. Na podstawie wodnych wyciągów z kory określono zasięg oddziaływania pyłów cementowo-wapienniczych na środowisko. Zależności pomiędzy pHH2O kory a odległością od źródła emisji pyłów badano metodą analizy regresji i korelacji liniowej. Wyniki badań odnoszono do wyników uzyskanych na leśnej powierzchni kontrolnej - wolnej od zanieczyszczeń alkalicznych. W miarę oddalania od źródła zanieczyszczeń opad pyłów cementowo-wapienniczych obniża się, co jest zrozumiałe, i znajduje potwierdzenie w zmiennych wartościach pHH2O kory sosny. Najsilniej odnotowano presję w kierunku NE, ES i SW, gdzi…
Capacità portante di mensole tozze in calcestruzzo fibroso o rinforzate con FRP
2004
Financial Aspects of Cervical Disc Arthroplasty: A Narrative Review of Recent Literature
2020
Recently, there has been significant interest in understanding the cost-effectiveness of treatments in spine surgery as health care systems in the United States move toward value-based care and alternative payment models. Previous studies have shown comparable outcomes of cervical disc arthroplasty (CDA) and anterior cervical discectomy fusion; however, there is a lack of consensus on the cost-effectiveness of CDA to support full adoption. Evidence of the limitations of these cost-analysis studies also exists in the literature, including industry funding, potential selection bias, and varying methods of calculating value. The goal of this narrative review is to provide an overview of the co…
Safety and efficacy of cervical disc arthroplasty in preventing the adjacent segment disease: a meta-analysis of mid- to long-term outcomes in prospe…
2019
Objectives: Cervical disc arthroplasty (CDA) has become an alternative treatment for cervical radiculopathy and myelopathy. This technique preserves appropriate motion at both the index and adjacent disc levels and consequently may prevent adjacent segment degeneration (ASD). The authors performed a meta-analysis to compare the safety and efficacy of CDA to those of the gold standard, anterior cervical discectomy and fusion (ACDF). Both surgical and clinical parameters were employed to verify the hypothesis that CDA can reduce the risk of ASD. Methods: The meta-analysis comprised high-quality randomized controlled trials that compared CDA and ACDF treatments of cervical degenerative disc di…
Ecological and evolutionary consequences of selective interspecific information use
2023
Recent work has shown that animals frequently use social information from individuals of their own species as well as from other species; however, the ecological and evolutionary consequences of this social information use remain poorly understood. Additionally, information users may be selective in their social information use, deciding from whom and how to use information, but this has been overlooked in an interspecific context. In particular, the intentional decision to reject a behaviour observed via social information has received less attention, although recent work has indicated its presence in various taxa. Based on existing literature, we explore in which circumstances selective i…
Designing Silylatedl-Amino Acids using a Wittig Strategy: Synthesis of Peptide Derivatives and18F-Labelling
2017
An efficient semisynthesis of silylated l-amino acids by reaction of silylated benzaldehydes with a phosphonium l-amino acid used as a Wittig reagent is described. The efficiency of the silylated l-amino acids in peptide synthesis was investigated by coupling both the carboxylic acid and the amino moiety with l-alanine and phenylalanine derivatives, respectively. The silylated derivatives were treated with KF or tetrabutylammonium fluoride to give the corresponding fluorosilyl derivatives without racemization. The hydrolysis of the fluorosilylated derivatives in phosphate buffer at pH 7.2 was checked. Finally, the 18F-labelling of di-tert-butylsilylated saturated and unsaturated dipeptides …
Cross-modal interactions between taste and smell: Odour-induced saltiness enhancement depends on salt level
2011
International audience; In recent years, health concerns related to salt have led to extensive research on low-salt foods. One major remaining issue is to reduce sodium content while still providing the salty fix, to maintain food appreciation, acceptance and choice. Using well-selected odours has been proposed to compensate for sodium chloride reduction in food, due to the cross-modal interactions between odour and taste. However, interactions between taste and odour, with regards to saltiness, remain poorly investigated. Moreover, although a few studies have assessed the influences of odour and sweet supra-threshold intensity on cross-modal interactions, none focused directly on how they …
Palladium-Catalyzed Reaction of Boronic Acids with Chiral and Racemic ?-Bromo Sulfoxides.
2005
Palladium-catalyzed cross-coupling reactions of racemic α-bromo sulfoxides with boronic acids are carried out in either aqueous or nonaqueous medium with formation of a new C sp3−C sp2 bond. The arylation of chiral α-bromo sulfoxides occurs without racemization. The cross-coupling reaction is general and gives high yields with arylboronic acids substituted with either donor or acceptor groups but gives poor results with heteroarylboronic acids. The best yields are obtained using degassed solvents and CsF instead of aqueous base. The use of aqueous base and the presence of oxygen favor the homocoupling side reaction.