Chemistry

1805 Submissions

[8] viXra:1805.0494 [pdf] submitted on 2018-05-29 06:31:04

Evaluation of Activation Energy on Adsorption of Tenuazonic Acid from Acid Bacteriafruit Juice by Inactivated Lactic

Authors: Rak-Chon Kim, Un-Ju Pak, Ok-Byol Ri
Comments: 6 Pages.

In this work, the adsorption of tenuazonic acid (TeA) by inactivated lactic acid bacteria (LAB) published by Liu et al. (J. Food Eng. 224 (2018) 45-52) was reevaluated using deactivation kinetic model (DKM). As the result, the reaction order and the activation energies were newly calculate d. Keywords: Adsorption, Kinetics, Modeling
Category: Chemistry

[7] viXra:1805.0324 [pdf] submitted on 2018-05-17 23:34:00

Bond Lengths in a Carbocation Explained in terms of Covalent Radius, Ground State Bohr Radius and the Golden Ratio

Authors: Raji Heyrovska
Comments: 5 pages, two Figures

The author has shown previously that the Golden ratio based ionic radii explain quantitatively the bond lengths in completely ionic as well as partially ionic bonds including hydrogen bonds. These ionic radii and covalent radii were shown to be additive in small as well as large molecules. This work shows that the published bond length data for a carbocation can also be explained using the covalent and Bohr radii and the Golden section of the ground state Bohr radius of carbon.
Category: Chemistry

[6] viXra:1805.0287 [pdf] submitted on 2018-05-15 03:50:04

Establishment of Reasonable Coating Processing of Sample for Scanning Electronic Microscope(sem) Measurement of Nano Material

Authors: Kwang-Il Kim, Il-Man Pak, Tae-Min Ro
Comments: 5 Pages.

The scanning electron microscope has a high resolution, image measurement and micro-zone analysis functions, and is a powerful means in analyzing nanomaterials. However, it is very difficult to measure nanomaterials under tens of nanometers from nanomaterials with deep concave convexes, including nano powders. ㎛-grade porous nanomaterials, the image quality of the scanning electron microscope is improved by the composite coating method of C and Au. [3] Here, a reasonable sample coating process for improving the image quality in the scanning electron microscopic measurement of the nanomaterial was established.
Category: Chemistry

[5] viXra:1805.0286 [pdf] submitted on 2018-05-15 03:55:04

Establishment of Reasonable Coating Processing of Sample for Scanning Electronic Microscope(sem) Measurement of Nano Materialdetermination of Reasonable Control Parameters for Scanning Electronic Microscope(sem) Measurement of Nano Powder

Authors: Kwang-Il Kim, Il-Man Pak, Tae-Min Ro
Comments: 4 Pages.

The scanning electron microscope has a high resolution, image measurement and micro-zone analysis functions, and is a powerful means in analyzing nanomaterials. However, it is very difficult to measure nanomaterials under tens of nanometers from nanomaterials with deep concave convexes, including nano powders. ㎛-grade porous nanomaterials, the image quality of the scanning electron microscope is improved by the composite coating method of C and Au. [3] Here, a reasonable sample coating process for improving the image quality in the scanning electron microscopic measurement of the nanomaterial was established.
Category: Chemistry

[4] viXra:1805.0244 [pdf] submitted on 2018-05-11 06:42:59

Dynamic Changes in the Structure, Chemical State and Catalytic Selectivity of cu Nanocubes During Co2 Electroreduction: Size and Support Effects

Authors: Philipp Grosse, Dunfeng Gao, Fabian Scholten, Ilya Sinev, Hemma Mistry, Beatriz Roldan Cuenya
Comments: 31 Pages. Angewandte Chemie 2018

In situ and operando spectroscopic and microscopic methods were used to gain insight into the correlation between the structure, chemical state, and reactivity of size- and shape-controlled ligand-free Cu nanocubes (Cu-cubes) during CO2 electroreduction (CO2RR). Dynamic changes in the morphology and composition of Cu-cubes supported on carbon were monitored under potential control via electrochemical atomic force microscopy, X-ray absorption fine-structure spectroscopy and X-ray photoelectron spectroscopy. Under reaction conditions, the roughening of the nanocube surface, disappearance of the (100) facets, formation of pores, loss of Cu and reduction of CuOx species observed were found to lead to a suppression of the selectivity for multi-carbon products (i.e. C2H4 and ethanol) versus CH4. A comparison with Cu-cubes supported on Cu foils revealed an enhanced morphological stability and persistence of Cu(I) species under CO2RR. Both factors are held responsible for the higher C2/C1 product ratio observed for the Cu cubes/Cu as compared to Cu cubes/C. Our findings highlight the importance of the structure of the active nanocatalyst but also its interaction with the underlying substrate in CO2RR selectivity.
Category: Chemistry

[3] viXra:1805.0243 [pdf] submitted on 2018-05-11 06:54:27

Prism-Shaped cu Nanocatalysts for Electrochemical Co2 Reduction to Ethylene

Authors: Hyo Sang Jeon, Sebastian Kunze, Fabian Scholten, Beatriz Roldan Cuenya
Comments: 24 Pages. ACS Catalysis 2018

Electrochemical CO2 reduction has attracted much attention due to its advantages to convert CO2 gas into useful chemicals and fuels. Herein, we have developed prism-shaped Cu catalysts for efficient and stable CO2 electrore-duction by using an electrodeposition method. These Cu prism electrodes were characterized by scanning electron mi-croscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Electrochemical CO2 reduction measurements show improved activities for C2H4 production with high partial current density of -11.8 mA/cm2, which is over four times higher than that of the planar Cu sample (-2.8 mA/cm2). We have demonstrated that the enhanced C2H4 production is partially attributed to the higher density of defect sites available on the roughened Cu prism surface. Furthermore, stability tests show a drastic improvement in maintaining C2H4 production over 12 hours. The enhanced performance and durability of prism Cu catalysts hold promise for future industrial applications.
Category: Chemistry

[2] viXra:1805.0242 [pdf] submitted on 2018-05-11 07:01:50

Enhanced Carbon Dioxide Electroreduction to Carbon Monoxide Over Defect Rich Plasma-Activated Silver Catalysts

Authors: Hemma Mistry, Yong-Wook Choi, Alexander Bagger, Fabian Scholten, Cecile Bonifacio, Ilya Sinev, Nuria J. Divins, Ioannis Zegkinoglou, Hyo Sang Jeon, Kim Kisslinger, Eric A. Stach, Judith C. Yang, Jan Rossmeisl, Beatriz Roldan Cuenya
Comments: 46 Pages. Angewandte Chemie 2017

Efficient, stable catalysts with high selectivity for a single product are essential to making the electroreduction of CO2 a viable route to the synthesis of industrial feedstocks and fuels. We reveal how a plasma oxidation pre-treatment can lead to an enhanced content of low-coordinated active sites which dramatically lower the overpotential and increase the activity of CO2 electroreduction to CO. At -0.6 V vs. RHE, more than 90% Faradaic efficiency towards CO could be achieved on a pre-oxidized silver foil. While transmission electron microscopy and operando X-ray absorption spectroscopy showed that oxygen species can survive in the bulk of the catalyst during the reaction, quasi-in situ X-ray photoelectron spectroscopy showed that the surface is metallic under reaction conditions. DFT calculations show how the defect-rich surface of the plasma-oxidized silver foils in the presence of local electric fields results in a drastic decrease in the overpotential for the electroreduction of CO2.
Category: Chemistry

[1] viXra:1805.0120 [pdf] submitted on 2018-05-04 12:44:00

AI Based Catalysis Informatics Framework Using JI Prolog/jCompound Mapper/JikesRVM/IoT Computing Environments – A Novel Insight into the Chemical Informatics World of Catalysis.

Authors: Nirmal Tej kumar
Comments: 3 Pages. Artificial Intelligence(AI) Based Chemical Informatics Notes.

As explained in the TITLE mentioned above,we intend to explore the informatics aspects of Catalysis using Java related technologies.
Category: Chemistry