Strategy for product composition control in the Hanford Waste Vitrification Plant

Acetone transformation catalyzed by HZSM-5 and NaZSM-5 zeolites and by zeolites modified with basic oxides was studied in an integral reactor at a temperature of 350 °C. Modification of acido-basic properties of ZSM-5 zeolites resulted both in the total conversion changes and in the essential changes in the product composition. Isobutene was found to be the main product over HZSM-5 zeolites exhibiting low activity, while aromatics prevailed when high conversion level was attained. Classical condensation of acetone yielding mesityloxide and phorones was observed over NaZSM-5 zeolites impregnated with CaO and ZnO.

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Radical copolymerization on fluoroalkyl α-chloroacrylate monomers for copolymer composition control

Polymer Bulletin ◽

10.1007/s00289-021-03597-x ◽

2021 ◽

Author(s):

Ikuo Yamamoto ◽

Shinichi Minami ◽

Tsuyoshi Ando ◽

Hiroharu Ajiro

Keyword(s):

Radical Copolymerization ◽

Copolymer Composition ◽

Composition Control

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Efficient Perovskite Solar Cells Achieved using the 2-Methoxyethanol Additive: Morphology and Composition Control of Intermediate Film

ACS Applied Energy Materials ◽

10.1021/acsaem.0c03227 ◽

2021 ◽

Vol 4 (3) ◽

pp. 2681-2689

Author(s):

Liuxing Guo ◽

Yi Chen ◽

Ge Wang ◽

Yiqiu Xia ◽

Dongxu Luo ◽

...

Keyword(s):

Solar Cells ◽

Perovskite Solar Cells ◽

Composition Control

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Elemental composition control of gold-titania nanocomposites by site-specific mineralization using artificial peptides and DNA

Communications Chemistry ◽

10.1038/s42004-020-00440-8 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Makoto Ozaki ◽

Takahito Imai ◽

Takaaki Tsuruoka ◽

Shungo Sakashita ◽

Kin-ya Tomizaki ◽

...

Keyword(s):

Visible Light ◽

Elemental Composition ◽

Inorganic Compounds ◽

Medical Science ◽

Induction Effect ◽

Site Specific ◽

Composition Control ◽

Light Excitation ◽

Titania Photocatalyst ◽

Scale Control

AbstractBiomineralization, the precipitation of various inorganic compounds in biological systems, can be regulated in terms of the size, morphology, and crystal structure of these compounds by biomolecules such as proteins and peptides. However, it is difficult to construct complex inorganic nanostructures because they precipitate randomly in solution. Here, we report that the elemental composition of inorganic nanocomposites can be controlled by site-specific mineralization by changing the number of two inorganic-precipitating peptides bound to DNA. With a focus on gold and titania, we constructed a gold-titania photocatalyst that responds to visible light excitation. Both microscale and macroscale observations revealed that the elemental composition of this gold-titania nanocomposite can be controlled in several ten nm by changing the DNA length and the number of peptide binding sites on the DNA. Furthermore, photocatalytic activity and cell death induction effect under visible light (>450 nm) irradiation of the manufactured gold-titania nanocomposite was higher than that of commercial gold-titania and titania. Thus, we have succeeded in forming titania precipitates on a DNA terminus and gold precipitates site-specifically on double-stranded DNA as intended. Such nanometer-scale control of biomineralization represent a powerful and efficient tool for use in nanotechnology, electronics, ecology, medical science, and biotechnology.

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Rendering Fat and Heavy Fischer-Tropsch Waxes Mixtures (0–100%) Fast Pyrolysis Tests for the Production of Ethylene and Propylene

Processes ◽

10.3390/pr9020367 ◽

2021 ◽

Vol 9 (2) ◽

pp. 367

Author(s):

Martyna Murat ◽

Zahra Gholami ◽

Josef Šimek ◽

Daily Rodríguez-Padrón ◽

José Miguel Hidalgo-Herrador

Keyword(s):

Linear Chain ◽

High Energy ◽

Chain Structure ◽

Nitrogen Atmosphere ◽

Energy Materials ◽

Fischer Tropsch ◽

Pyrolysis Products ◽

Product Composition ◽

Rendered Fat ◽

Linear Chain Structure

A great emphasis is placed on searching for efficient sources to produce renewable fuels due to the actual trends in avoiding the use of fossil resources to mitigate the environment’s deterioration. Thus, the use of waste from the food or wood industry for the production of biofuels is widely researched and may contribute to sustainable general development. Rendered fat and Fischer-Tropsch waxes are high-energy materials which could be used for the pyrolysis reaction. Therefore, in this study, the effect of reaction parameters and feedstock composition on the distribution of the pyrolysis products has been examined. The experiments were carried out in a nitrogen atmosphere in a multi-shot pyrolizer instrument equipped with GC-FID. First, the influence of the temperature was examined at 785, 800, and 815 °C. The highest yield to olefins was observed at 815 °C. The effect of triglycerides and paraffins contents (0–100% with 10% ramp) in the feedstock on the product composition was investigated at 815 °C. The gas chromatography analyses revealed that the feedstock composition did not significantly affect the product composition due to the high temperature and the long linear chain structure similarities between the free fatty acids and Fischer-Tropsch waxes.

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