Thermal decomposition of ammonium hexachloroosmate

In view of the constant search for new sources of renewable energy, the particulate agro-industrial waste reuse emerges as an advantageous alternative. However, despite the advantages of using the biomass as an energy source, there is still strong resistance as the large-scale replacement of petroleum products due to the lack of scientifically proven efficient conversion technologies. In this context, the pyrolysis is presented as one of the most widely used thermal decomposition processes. The knowledge of aspects of chemical kinetics, thermodynamics these will, heat and mass transfer, are so important, since influence the quality of the product. This paper presents a kinetic study of slow pyrolysis of coffee grounds waste from dynamic thermogravimetric experiments (TG), using different powder catalysts. The primary thermal decomposition was described by the one-step reaction model, which considers a single global reaction. The kinetic parameters were estimated using nonlinear regression and the differential evolution method. The coffee ground waste was dried at 105°C for 24 hours. The sample in nature was analyzed at different heating rates, being 10, 15, 20, 30 and 50 K/min. In the catalytic pyrolysis, about 5% (w/w) of catalyst were added to the sample, at a heating rate of 30 K/min. The results show that the one-step model does not accurately represent the data of weight loss (TG) and its derivative (DTG), but can do an estimative of the activation energy reaction, and can show the differences caused by the catalysts. Although no one can say anything about the products formed with the addition of the catalyst, it would be necessary to micro-pyrolysis analysis, we can say the influence of the catalyst in the samples, based on the data obtained in thermogravimetric tests.

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Application of β-Phosphorylated Nitroethenes in [3+2] Cycloaddition Reactions Involving Benzonitrile N-Oxide in the Light of a DFT Computational Study

Organics ◽

10.3390/org2010003 ◽

2021 ◽

Vol 2 (1) ◽

pp. 26-37

Author(s):

Karolina Zawadzińska ◽

Karolina Kula

Keyword(s):

Density Functional ◽

Reaction Path ◽

Computational Study ◽

Cyano Group ◽

Cycloaddition Reactions ◽

Functional Theory ◽

The Density Functional Theory ◽

Reaction Channels ◽

One Step ◽

Step Mechanism

The regiochemistry of [3+2] cycloaddition (32CA) processes between benzonitrile N-oxide 1 and β-phosphorylated analogues of nitroethenes 2a–c has been studied using the Density Functional Theory (DFT) at the M062X/6-31+G(d) theory level. The obtained results of reactivity indices show that benzonitrile N-oxide 1 can be classified both as a moderate electrophile and moderate nucleophile, while β-phosphorylated analogues of nitroethenes 2a–c can be classified as strong electrophiles and marginal nucleophiles. Moreover, the analysis of CDFT shows that for [3+2] cycloadditions with the participation of β-phosphorylatednitroethene 2a and β-phosphorylated α-cyanonitroethene 2b, the more favored reaction path forms 4-nitro-substituted Δ2-isoxazolines 3a–b, while for a reaction with β-phosphorylated β-cyanonitroethene 2c, the more favored path forms 5-nitro-substituted Δ2-isoxazoline 4c. This is due to the presence of a cyano group in the alkene. The CDFT study correlates well with the analysis of the kinetic description of the considered reaction channels. Moreover, DFT calculations have proven the clearly polar nature of all analyzed [3+2] cycloaddition reactions according to the polar one-step mechanism.

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One-step synthesis of CoO/g-C3N4 composites by thermal decomposition for overall water splitting without sacrificial reagents

Inorganic Chemistry Frontiers ◽

10.1039/c7qi00380c ◽

2017 ◽

Vol 4 (10) ◽

pp. 1691-1696 ◽

Cited By ~ 24

Author(s):

Mumei Han ◽

Huibo Wang ◽

Siqi Zhao ◽

Lulu Hu ◽

Hui Huang ◽

...

Keyword(s):

Thermal Decomposition ◽

Visible Light ◽

Water Splitting ◽

Visible Light Irradiation ◽

Photocatalytic Performance ◽

Light Irradiation ◽

Overall Water Splitting ◽

One Step ◽

Good Photocatalytic Performance

10%CoO/g-C3N4 exhibits good photocatalytic performance under visible light irradiation without any sacrificial reagents.

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One-Step Extrusion to Minimize Thermal Decomposition for Processing PLA-Based Composites

Journal of Polymers and the Environment ◽

10.1007/s10924-018-1323-3 ◽

2018 ◽

Vol 27 (1) ◽

pp. 158-164 ◽

Cited By ~ 1

Author(s):

Qingfei Duan ◽

Linghan Meng ◽

Hongsheng Liu ◽

Long Yu ◽

Kai Lu ◽

...

Keyword(s):

Thermal Decomposition ◽

One Step

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Unveiling the Unexpected Reactivity of Electrophilic Diazoalkanes in [3+2] Cycloaddition Reactions within Molecular Electron Density Theory

10.20944/preprints202012.0364.v1 ◽

2020 ◽

Author(s):

Luis R. Domingo ◽

Mar Ríos-Gutiérrez ◽

Nivedita Acharjee

Keyword(s):

Electron Density ◽

Complete Agreement ◽

Slowing Down ◽

Molecular Electron ◽

One Step ◽

Molecular Electron Density Theory ◽

Electrophilic Character ◽

Step Mechanism ◽

Computational Level ◽

Density Transfer

The [3+2] cycloaddition (32CA) reactions of strongly nucleophilic norbornadiene (NBD) with simplest diazoalkane (DAA) and three DAAs of increased electrophilicity have been studied within the Molecular Electron Density Theory (MEDT) at the MPWB1K/6-311G(d,p) computational level. These pmr-type 32CA reactions follow an asynchronous one-step mechanism with activation enthalpies ranging from 17.7 to 27.9 kcal·mol-1 in acetonitrile. The high exergonic character of these reactions makes them irreversible. The presence of electron-withdrawing (EW) substituents in the DAA increases the activation enthalpies, in complete agreement with the experimental slowing-down of the reactions, but contrary to the Conceptual DFT prediction. Despite the nucleophilic and electrophilic character of the reagents, the global electron density transfer at the TSs indicates rather non-polar 32CA reactions. The present MEDT study allows establishing that the depopulation of the NNC core in this series of DAAs with the increase of the EW character of the substituents present at the carbon center is responsible for the experimentally found deceleration.

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Laser-excited immunofluorometric assay of prolactin, with use of antibodies coupled to lanthanide-labeled diethylenetriaminepentaacetic acid.

Clinical Chemistry ◽

10.1093/clinchem/32.7.1323 ◽

1986 ◽

Vol 32 (7) ◽

pp. 1323-1327 ◽

Cited By ~ 18

Author(s):

H Déchaud ◽

R Bador ◽

F Claustrat ◽

C Desuzinges

Keyword(s):

Plasma Sample ◽

Solid Phase ◽

Nitrogen Laser ◽

Diethylenetriaminepentaacetic Acid ◽

Time Resolved Fluorescence ◽

Time Resolved ◽

Step Procedure ◽

Polystyrene Tube ◽

Sandwich Type ◽

One Step

Abstract We describe an immunofluorometric assay for prolactin based on lanthanide labeling of a monoclonal antibody and measuring time-resolved fluorescence. In this "sandwich"-type assay, the label (Eu3+) was bound to the second antibody by means of a simple, rapid method involving the anhydride of diethylenetriaminepentaacetic acid. To measure the photoluminescence of europium (or other lanthanides), we have developed a time-resolved fluorometer with a nitrogen laser as the pulsed excitation source. During the assay, the solid-phase antibody immobilized inside a polystyrene tube is incubated with the plasma sample and the second antibody in a one-step procedure. Results for 67 human plasmas correlated well (r = 0.98) with those by an immunoradiometric method.

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Thermal decomposition assisted one-step synthesis of high surface area NiCoP nanospheres for simultaneous sensing of Lead, Mercury and Cadmium ions in groundwater samples

Journal of Electroanalytical Chemistry ◽

10.1016/j.jelechem.2020.113937 ◽

2020 ◽

Vol 861 ◽

pp. 113937 ◽

Cited By ~ 2

Author(s):

Lignesh Durai ◽

Arthi Gopalakrishnan ◽

Sushmee Badhulika

Keyword(s):

Thermal Decomposition ◽

Surface Area ◽

High Surface ◽

High Surface Area ◽

Cadmium Ions ◽

Groundwater Samples ◽

One Step ◽

Simultaneous Sensing

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Two new two-step immunoassays for free thyroxin evaluated: solid-phase radioimmunoassay and time-resolved fluoroimmunoassay

Clinical Chemistry ◽

10.1093/clinchem/36.7.1355 ◽

1990 ◽

Vol 36 (7) ◽

pp. 1355-1360 ◽

Cited By ~ 17

Author(s):

P Nuutila ◽

P Koskinen ◽

K Irjala ◽

L Linko ◽

H L Kaihola ◽

...

Keyword(s):

Solid Phase ◽

Equilibrium Dialysis ◽

Late Pregnancy ◽

Clinical State ◽

Albumin Concentration ◽

Time Resolved ◽

One Step ◽

Solid Phase Radioimmunoassay ◽

Dialysis Method ◽

Method R

Abstract We measured concentrations of free thyroxin (FT4) in serum by using two new two-step FT4 assays--a solid-phase two-step radioimmunoassay. Spectria, and a time-resolved fluoroimmunoassay. Delfia--and compared the results with those by a two-step FT4 assay (RIA-gnost), a one-step FT4 analog assay (Amerlex-M), and FT4 measured after equilibrium dialysis. The new FT4 assays classified 30 hypothyroid and 43 hyperthyroid patients (untreated) well. In 138 patients with nonthyroidal illness (NTI) and in late pregnancy (n = 36), fewer subnormal FT4 values were reported by Spectria (P less than 0.001), Delfia (P less than 0.001), and RIA-gnost (P less than 0.01) than by Amerlex-M. The results of the Spectria and Delfia methods correlated with the results of the dialysis method (r = 0.76) in NTI patients and pregnancy, and were in better agreement with the clinical state than was FT4 by Amerlex-M. The FT4 values by Amerlex-M, but not by other methods, correlated with albumin concentration. We conclude that these new two-step methods present good alternatives for FT4 analysis.

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Construction of amorphous interface in an interwoven NiS/NiS2 structure for enhanced overall water splitting

Journal of Materials Chemistry A ◽

10.1039/c8ta01928b ◽

2018 ◽

Vol 6 (18) ◽

pp. 8233-8237 ◽

Cited By ~ 61

Author(s):

Qun Li ◽

Dewen Wang ◽

Ce Han ◽

Xiao Ma ◽

Qingqing Lu ◽

...

Keyword(s):

Thermal Decomposition ◽

Water Splitting ◽

Nickel Sulfate ◽

Overall Water Splitting ◽

One Step

Here, we describe the synthesis of a novel interwoven NiS/NiS2 structure with an amorphous interface accomplished by carrying out a one-step thermal decomposition of nickel sulfate and thiourea.

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Understanding the Reactivity of Trimethylsilyldiazoalkanes Participating in [3+2] Cycloaddition Reactions towards Diethylfumarate with a Molecular Electron Density Theory Perspective

Organics ◽

10.3390/org1010002 ◽

2020 ◽

Vol 1 (1) ◽

pp. 3-18

Author(s):

Luis R. Domingo ◽

Nivedita Acharjee ◽

Haydar A. Mohammad-Salim

Keyword(s):

Electron Density ◽

Energy Cost ◽

Trimethylsilyl Group ◽

Gibbs Energies ◽

Molecular Electron ◽

One Step ◽

Molecular Electron Density Theory ◽

Non Covalent Interactions ◽

Covalent Interactions ◽

Step Mechanism

A Molecular Electron Density Theory (MEDT) study is presented here for [3+2] cycloaddition (32CA) reactions of three trimethylsilyldiazoalkanes with diethyl fumarate. The presence of silicon bonded to the carbon of these silyldiazoalkanes changes its structure and reactivity from a pseudomonoradical to that of a zwitterionic one. A one-step mechanism is predicted for these polar zw-type 32CA reactions with activation enthalpies in CCl4 between 8.0 and 19.7 kcal·mol−1 at the MPWB1K (PCM)/6-311G(d,p) level of theory. The negative reaction Gibbs energies between −3.1 and −13.2 kcal·mole−1 in CCl4 suggests exergonic character, making the reactions irreversible. Analysis of the sequential changes in the bonding pattern along the reaction paths characterizes these zw-type 32CA reactions. The increase in nucleophilic character of the trimethylsilyldiazoalkanes makes these 32CA reactions more polar. Consequently, the activation enthalpies are decreased and the TSs require less energy cost. Non-covalent interactions at the TSs account for the stereoselectivity found in these 32CA reactions involving the bulky trimethylsilyl group.

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