Search results for "Methylene"

Sensory performance of blind Mexican cave fish after destruction of the canal neuromasts.

1990

The growth of soil fungi Penicillium in the presence of N-(2-pyridylamino)methylenebisphosphonate as an alternative source of nutrients

2017

Kwas N-(2-pirydyloamino)metylenobisfosfonowy wykazują dużą aktywność herbicydową. W związku z tym należy zbadać jego odziaływanie na mikroorganizmy glebowe. Celem przeprowadzonych badań była ocena zdolności glebowych szczepów Penicillium do wzrostu w obecności kwasu N-(2-pirydyloamino)metylenobisfosfonowego jako alternatywnego źródła fosforu lub azotu lub węgla. Hodowle grzybów prowadzono w pełnym i zmodyfikowanym mineralnym podłożu Czapek, w temperaturze 25°C, przez 1–4 tygodnie. Modyfikacja podłoża polegała na wprowadzeniu 1 mM kwasu N-(2 pirydyloamino)metylenobisfosfonowego jako alternatywnego źródła składników odżywczych. Kontrolę względną stanowił wzrost grzybów w pełnym mineralnym pod…

CCDC 903571: Experimental Crystal Structure Determination

2013

Related Article: T.K.Ronson,C.Giri,N.K.Beyeh,A.Minkkinen,F.Topic,J.J.Holstein,K.Rissanen,J.R.Nitschke|2013|Chem.-Eur.J.|19|3374|doi:10.1002/chem.201203751

CCDC 2041018: Experimental Crystal Structure Determination

2021

Related Article: Goulielmina Anyfanti, Antonio Bauzá, Lorenzo Gentiluomo, João Rodrigues, Gustavo Portalone, Antonio Frontera, Kari Rissanen, Rakesh Puttreddy|2021|Frontiers in Chemistry|9||doi:10.3389/fchem.2021.623595

Enrichment and activation of smectite-poor clay

2011

A new method of smectite clay enrichment has been developed. The method is based on dispersing clay in a phosphate solution and sequential coagulation. The product of enrichment is characterized with X-ray powder diffraction, wavelength dispersive X-ray fluorescence spectrometry, differential thermal analysis and thermogravimetry. Sorption of methylene blue and hexadecylpyridinium bromide on raw and purified clays was studied.

<i>Geminal</i> Parahydrogen-Induced Polarization: Accumulating Long-Lived Singlet Order on Methylene Proton Pairs

2020

Abstract. In the majority of hydrogenative PHIP (Parahydrogen Induced Polarization) experiments, the hydrogen molecule undergoes pairwise cis-addition to an unsaturated precursor to occupy vicinal positions on the product molecule. However, some ruthenium-based hydrogenation catalysts induce geminal hydrogenation, leading to a reaction product in which the twohydrogen atoms are transferred to the same carbon center, forming a methylene (CH2) group. The singlet order of parahydrogen is substantially retained over the geminal hydrogenation reaction, giving rise to a singlet-hyperpolarized CH2 group. Although the T1 relaxation times of the methylene protons are often short, the singlet order h…

Catalytic activity of humic substances in condensation reactions

1998

Abstract Humic substances (HS) have considerable impact on the fate of organic xenobiotics in natural environments. This paper reports on the catalytic activity of HS in condensation reactions of carbonyl compounds with active methylene compounds, using Knoevenagel and Claisen-Schmidt reactions as examples. Of the HS, the aquatic fulvic acids are the most active, but the velocity of condensation reactions depends also on the temperature, concentration and form of HS (free or salt) used, and the solvent.

Morphology and Progression in Primary Varicose Vein Disorder Due to 677C>T and 1298A>C Variants of MTHFR

2015

Background: Clinical assessment and prognostic stratification of primary varicose veins have remained controversial and the molecular pathogenesis is unknown. Previous data have suggested a contribution of the MTHFR (methylenetetrahydrofolate reductase) polymorphism c.677C>T. Methods: We collected blood and vein specimens from 159 consecutive patients undergoing varicose vein surgery, or autologous vein reconstruction for arterial occlusive disease as controls. We compared the frequencies of c.677C>T and another polymorphism of MTHFR, c.1298A>C, with morphology and types of complicated disease. Morphology was recorded as a trunk or perforator type and peripheral congestive complication was …

Palladium-Catalyzed Direct Arylation of Heteroaromatics with Activated Aryl Chlorides Using a Sterically Relieved Ferrocenyl-Diphosphane

2012

International audience; The palladium-catalyzed direct arylations at C3 or C4 positions of heteroaromatics are known to be more challenging than at C2 or C5 positions. Aryl chlorides are also challenging substrates for direct arylation of heteroaromatics. We observed that in the presence of a palladium-catalyst combining only 0.5 mol % of Pd(OAc)2 with the sterically relieved new ferrocenyl diphosphane Sylphos, the direct arylation at C3 or C4 of oxazoles, a benzofuran, an indole, and a pyrazole was found to proceed in moderate to high yields using a variety of electron deficient aryl chlorides. Turnover numbers up to 176 have been obtained with this catalyst. Assessment of the electron-don…

Effects of polymorphisms in endothelial nitric oxide synthase and folate metabolizing genes on the concentration of serum nitrate, folate, and plasma…

2015

Abstract Objectives A number of studies have explored the effects of dietary nitrate on human health. Nitrate in the blood can be recycled to nitric oxide, which is an essential mediator involved in many important biochemical mechanisms. Nitric oxide is also formed in the body from l -arginine by nitric oxide synthase. The aim of this study was to investigate whether genetic polymorphisms in endothelial nitric oxide synthase (eNOS) and genes involved in folate metabolism affect the concentration of serum nitrate, serum folate, and plasma total homocysteine in healthy individuals after folic acid supplementation. Methods In a randomized double-blind, crossover study, participants were given …