9 results match your criteria: "Cid. Univ.[Affiliation]"

Unveiling distinct bonding patterns in noble gas hydrides interference energy analysis.

Phys Chem Chem Phys

January 2025

School of Chemistry and Forensic Science, University of Kent, Park Wood Rd, Canterbury CT2 7NH, UK.

Despite their apparent simplicity, the helium hydride ion (HeH) and its analogues with heavier noble gas (Ng) atoms present intriguing challenges due to their unusual electronic structures and distinct ground-state heterolytic bond dissociation profiles. In this work, we employ modern valence bond calculations and the interference energy analysis to investigate the nature of the chemical bond in NgH (Ng = He, Ne, Ar). Our findings reveal that the energy well formation in their ground-state potential energy curves is driven by a reduction in kinetic energy caused by quantum interference, identical to cases of homolytic bond dissociation.

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The global imperative to shift towards renewable and sustainable resources has spurred significant interest in exploring and utilizing platform chemicals derived from renewable feedstocks. Among these, levoglucosenone (LGO) and Cyrene™ have emerged as promising candidates. LGO, derived from the pyrolysis of cellulose and hemicellulose, exhibits structural versatility, making it an attractive starting material for various valuable products.

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pyMSER─An Open-Source Library for Automatic Equilibration Detection in Molecular Simulations.

J Chem Theory Comput

October 2024

IBM Research, Av. República do Chile, 330, Rio de Janeiro, Rio de Janeiro CEP 20031-170, Brazil.

Automated molecular simulations are used extensively for predicting material properties. Typically, these simulations exhibit two regimes: a dynamic equilibration part, followed by a steady state. For extracting observable properties, the simulations must first reach a steady state so that thermodynamic averages can be taken.

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Superelectrophilic Nonclassical Carbocations.

J Org Chem

July 2024

Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, United States.

The chemistry of dicationic and tricationic 2-norbornyl cations has been studied. A series of -heterocyclic functionalized norborneol substrates were prepared and ionization of these compounds in superacid provided superelectrophilic species. These highly charged 2-norbornyl cations were found to react with arene nucleophiles in high yields and stereoselectivity.

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pyCOFBuilder: A Python Package for Automated Creation of Covalent Organic Framework Models Based on the Reticular Approach.

J Chem Inf Model

April 2024

Instituto de Química, Universidade Federal do Rio de Janeiro, Av. Athos da Silveira Ramos, 149, CT A-622, Cid. Univ., Rio de Janeiro, Rio de Janeiro 21941-909, Brazil.

Covalent organic frameworks (COFs) have gained significant popularity in recent years due to their unique ability to provide a high surface area and customizable pore geometry and chemistry, making them an ideal choice for a wide range of applications. However, exploring COFs experimentally can be arduous and time-consuming due to their immense number of potential structures. As a result, computational high-throughput studies have become an attractive option.

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Are all-atom any better than united-atom force fields for the description of liquid properties of alkanes?

J Mol Model

October 2020

Instituto de Química, Universidade Federal do Rio de Janeiro, Av. Athos da Silveira Ramos 149, CT, Bl. A-622, Cid. Univ., Rio de Janeiro, RJ, 21941-909, Brazil.

Alkanes are a fundamental part in empirical force fields (FF) not only due to their technological relevance, but also due to the prevalence of alkane moieties in organic molecules, e.g., compounds containing a saturated carbon chain.

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A Carbocationic Triarylmethane-Based Porous Covalent Organic Network.

Chemistry

February 2021

Instituto de Química, Universidade Federal do Rio de Janeiro, Av. Athos da Silveira Ramos, 149, CT, A-622, Cid. Univ., 21941-909, Rio de Janeiro, Brazil.

A thermally stable carbocationic covalent organic network (CON), named RIO-70 was prepared from pararosaniline hydrochloride, an inexpensive dye, and triformylphloroglucinol in solvothermal conditions. This nanoporous organic material has shown a specific surface area of 990 m  g and pore size of 10.3 Å.

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Effect of cholesterol depletion and temperature on the isolation of detergent-resistant membranes from human erythrocytes.

J Membr Biol

April 2010

Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas, Cid. Univ. Zeferino Vaz s/n, C.P. 6109, CEP 13083-970, Campinas, SP, Brazil.

Transient lateral microdomains or lipid rafts play important roles in many physiological membrane-mediated cell processes. Detergent-resistant membranes (DRMs) are good models for the study of lipid rafts. Here we report that DRMs can be obtained by treating human erythrocytes with the nonionic detergents Triton X-100 or octaethylene glycol monododecyl ether (C(12)E(8)) at 37 degrees C, and by treatment at 4 degrees C of cholesterol-depleted erythrocytes.

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Visan miospore biostratigraphy and correlation of the Poti Formation (Parnaba Basin, northern Brazil).

Rev Palaeobot Palynol

October 2000

Petrobras/Cenpes/Divex/Sebipe, Cid. Univ., Q.7, I. Fundao, 21949-900 RJ, Rio de Janeiro, Brazil

The Poti Formation, which consists mainly of sandstones with minor proportions of carbonaceous shales and other siliciclastic lithologies, represents all the Viséan strata thus far recorded in the Parnaíba Basin, northern Brazil.Well-preserved miospores featuring species with both Southern Euramerican and Gondwanan affinities have been recovered from this formation in four well sections. The most characteristic species are listed in this paper, and brief systematic descriptions are presented for the most significant species, along with comments on their biostratigraphy.

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