Post-treatment of TS-1 with Mixtures of TPAOH and Ammonium Salts and the Catalytic Properties in Propylene Epoxidation

Abstract Two enzymes, laccase and peroxidase, were immobilized on chloromethylated styrene-divinylbenzene copolymers supports functionalized with phosphonates ((RO)2PO) or mixed ammonium and phosphonium groups (N+R3Cl–, P+Ph3Cl–). Phosphonates groups and quaternary ammonium salts were grafted on the “gel-type” copolymer by Michaelis–Becker polymer analogue reaction. Mixed polymer-supported ammonium and phosphonium salts were obtained by transquaternization of the ammonium groups to phosphonium group. The degrees of functionalization for obtained polymers were relatively high ensuring a sufficient concentration of active centers per unit mass of the copolymer. The obtained materials were characterized by thermal analysis, FTIR spectroscopy and SEM microscopy. The effects of OR1 and R2 radicals from phosphonate and respectively ammonium groups, as well as those of glutaraldehyde utilization on the immobilization yield and the catalytic properties of the supported enzymes were indicated. The activity of enzymes increased after immobilization and high immobilization yield was obtained for all the samples. The higher interaction of enzymes with support was indicated for mixed ammonium and phosphonium functions. A higher catalytic activity was obtained for peroxidase in oxidation of phenol and laccase in oxidation of anisole. The low effect of glutaraldehyde on enzyme activity reveals the strong interaction of enzyme with the polymer support, respectively with the functional groups.

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Effect of ammonium salts on the synthesis and catalytic properties of TS-1

Microporous and Mesoporous Materials ◽

10.1016/j.micromeso.2009.03.018 ◽

2009 ◽

Vol 122 (1-3) ◽

pp. 301-308 ◽

Cited By ~ 29

Author(s):

Weibin Fan ◽

Binbin Fan ◽

Xiaohua Shen ◽

Junfen Li ◽

Peng Wu ◽

...

Keyword(s):

Catalytic Properties ◽

Ammonium Salts

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Effect of treatment with different bases on the catalytic properties of TS-1/SiO2 extrudates in propylene epoxidation

Microporous and Mesoporous Materials ◽

10.1016/j.micromeso.2015.03.026 ◽

2015 ◽

Vol 212 ◽

pp. 48-55 ◽

Cited By ~ 27

Author(s):

Wancang Song ◽

Guang Xiong ◽

Huayun Long ◽

Fengying Jin ◽

Liping Liu ◽

...

Keyword(s):

Catalytic Properties ◽

Propylene Epoxidation ◽

Effect Of Treatment

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Transformation of SiO2 in Titanium Silicalite-1/SiO2 extrudates during tetrapropylammonium hydroxide treatment and improvement of catalytic properties for propylene epoxidation

Chemical Engineering Journal ◽

10.1016/j.cej.2014.05.075 ◽

2014 ◽

Vol 253 ◽

pp. 464-471 ◽

Cited By ~ 26

Author(s):

Wancang Song ◽

Yi Zuo ◽

Guang Xiong ◽

Xiongfu Zhang ◽

Fengying Jin ◽

...

Keyword(s):

Catalytic Properties ◽

Titanium Silicalite ◽

Propylene Epoxidation ◽

Tetrapropylammonium Hydroxide

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Ultrastructure of bronchopulmonary lavage cells from bovines administered 3-methylindole: II. 24 hours post-treatment

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111124 ◽

1984 ◽

Vol 42 ◽

pp. 202-203

Author(s):

Amreek Singh ◽

Judith M. McLaren ◽

Onkar S. Atwal ◽

Peter Eyre

Keyword(s):

Plasma Cells ◽

Ciliated Cell ◽

Lavage Fluid ◽

Treated Group ◽

Post Treatment ◽

Lung Edema ◽

Ciliated Cells ◽

Thin Sections ◽

Variable Diameter ◽

Cell Pellet

Introduction3-methylindole (MI), a rumen metabolite of the amino acid L-tryptophan, has been shown to produce bovine pulmonary edema and emphysema. The airways contain free and exfoliated cells. A morphologic analysis of these cells may complement the understanding of the mechanism of lung edema. Ultrastructure of the bronchopulmonary lavage (BL) cells 24 h following MI oral administration to calves is described in this experiment. The 12 hours post-treatment results were described earlier.Materials and MethodsTwo Holstein-Friesian calves were each administered an oral dose of 0.2 g MI/Kg body weight and another two calves served as controls. The animals were euthanized with sodium pentabarbitol 24 h after receiving the compound. The lungs and trachea were removed and 0.1 M sodium phosphate buffered saline was infused into the lungs through the trachea. Glutaraldehyde fixative was added to the recovered BL fluid so as to form a 1% solution. The fluid was centrifuged and the resulting cell pellet was suspended in the buffer. The procedures were repeated on the suspension; the pellet was post-fixed in osmium tetroxide and was processed by conventional methods of section preparations for TEM examination. Lung samples from caudal lobes were fixed in 1.5% glutaraldehyde to obtain tissue sections for TEM.Results and DiscussionPulmonary alveolar macrophages (AM), neutrophils, ciliated epithelial cells, globule leukocytes and plasma cells were recovered from the BL fluid of the control and Mi-administered calves. Ciliated cells and globule leukocytes could not be harvested from the controls. The AM obtained from the treated calves (Fig. 1) in comparison with similar cells from the controls were larger, and contained large membrane-limited inclusions (phagolysosomes). There was a remarkable similarity between the lavaged AM and the AM studied in thin sections of lung (cf. Fig. 1 and Fig. 2). The neutrophil was the second most abundant cell type retrieved from the lavage fluid from the calves of control or treated group. Except for scanty pseudopodia in the neutrophils obtained from the Mi-receiving calves, the cells appeared unaltered (Fig. 3). Ciliated cells were abundant in the BL fluid of Mi-ingesting calves. A heterogeneous collection of vesicles filled the ciliated cell cytoplasm (Fig. 3). Globule leukocytes were commonly observed among BL cells of treated calves. The globule leukocytes were ca. 15 μm in diameter and contained round or elliptical nuclei with conspicuous nucleoli. The cytoplasmic granules, which are a prominent feature of globule leukocytes, were electron-opaque and had a variable diameter (0.5-3.0 μm). A one-line account of globule leukocytes in the bronchi of steers administered MI has appeared. Plasma cells were rare. Ultrastructure of BL cells is compatible with their response to chemical insult by MI.

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Microstructure and reactivity of small metal particles: The role of Ce additives

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121995 ◽

1992 ◽

Vol 50 (1) ◽

pp. 318-319

Author(s):

L.D. Schmidt ◽

K. R. Krause ◽

J. M. Schwartz ◽

X. Chu

Keyword(s):

Atmospheric Pressure ◽

Noble Metals ◽

Mixed Oxides ◽

Catalytic Properties ◽

Chemical Shifts ◽

Catalytic Converter ◽

Structural Evolution ◽

Single Particles ◽

Small Metal Particles

The evolution of microstructures of 10- to 100-Å diameter particles of Rh and Pt on SiO2 and Al2O3 following treatment in reducing, oxidizing, and reacting conditions have been characterized by TEM. We are able to transfer particles repeatedly between microscope and a reactor furnace so that the structural evolution of single particles can be examined following treatments in gases at atmospheric pressure. We are especially interested in the role of Ce additives on noble metals such as Pt and Rh. These systems are crucial in the automotive catalytic converter, and rare earths can significantly modify catalytic properties in many reactions. In particular, we are concerned with the oxidation state of Ce and its role in formation of mixed oxides with metals or with the support. For this we employ EELS in TEM, a technique uniquely suited to detect chemical shifts with ∼30Å resolution.

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Continuous Positive Airway Pressure (CPAP) Therapy for the Treatment of Hypernasality: A Single Case Study

Perspectives on Speech Science and Orofacial Disorders ◽

10.1044/ssod24.2.48 ◽

2014 ◽

Vol 24 (2) ◽

pp. 48-58 ◽

Cited By ~ 3

Author(s):

Lakshmi Kollara ◽

Graham Schenck ◽

Jamie Perry

Keyword(s):

Continuous Positive Airway Pressure ◽

Airway Pressure ◽

Positive Airway Pressure ◽

Single Case ◽

Treatment Method ◽

Post Treatment ◽

Subjective Perception ◽

Cpap Therapy ◽

Long Term Follow Up

Studies have investigated the applications of Continuous Positive Airway Pressure (CPAP) therapy in the treatment of hypernasality due to velopharyngeal dysfunction (VPD; Cahill et al., 2004; Kuehn, 1991; Kuehn, Moon, & Folkins, 1993; Kuehn et al., 2002). The purpose of this study was to examine the effectiveness of CPAP therapy to reduce hypernasality in a female subject, post-traumatic brain injury (TBI) and pharyngeal flap, who presented with signs of VPD including persistent hypernasality. Improvements in mean velopharyngeal orifice size, subjective perception of hypernasality, and overall intelligibility were observed from the baseline to 8-week post-treatment assessment intervals. Additional long-term assessments completed at 2, 3, and 4 months post-treatment indicated decreases in immediate post-treatment improvements. Results from the present study suggest that CPAP is a safe, non-invasive, and relatively conservative treatment method for reduction of hypernasality in selected patients with TBI. More stringent long-term follow up may indicate the need for repeated CPAP treatment to maintain results.

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