Surface Defect-Induced Site-Specific Dispersion of Pd Nanoclusters on TiO2 Nanoparticles for Semihydrogenation of Phenyl Acetylene

Abstract This paper demonstrates a novel method of XTEM sample preparation for site-specific surface defect analysis using backside polishing. Analysis of three different types of site-specific surface defects was demonstrated using a novel backside XTEM sample preparation method. The details of the backside XTEM sample preparation method and some examples are reported in this paper. Comparing to Auger electron spectrometry (AES) results on similar defects, more detailed and precise information is observed using TEM analysis with this method. It is therefore a complementary technique to traditional AES analysis on surface defects for contamination with atomic level concentration. From the results, the sample preparation method can produce a clean, pristine surface that is well characterized and could be reproduced, successfully.

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Mechanism of Laser-Induced Bulk and Surface Defect Generation in ZnO and TiO2 Nanoparticles: Effect on Photoelectrochemical Performance

ACS Applied Energy Materials ◽

10.1021/acsaem.8b00977 ◽

2018 ◽

Cited By ~ 3

Author(s):

Marcus Lau ◽

Sven Reichenberger ◽

Ina Haxhiaj ◽

Stephan Barcikowski ◽

Astrid M. Müller

Keyword(s):

Tio2 Nanoparticles ◽

Surface Defect ◽

Photoelectrochemical Performance ◽

Defect Generation ◽

Zno And Tio2 Nanoparticles

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Large-cluster and combined fluorescent and gold immunoprobes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166920 ◽

1996 ◽

Vol 54 ◽

pp. 892-893

Author(s):

Richard D. Powell ◽

James F. Hainfeld ◽

Carol M. R. Halsey ◽

David L. Spector ◽

Shelley Kaurin ◽

...

Keyword(s):

Metal Cluster ◽

Sulfonyl Chloride ◽

Gel Filtration ◽

Cross Linking ◽

Site Specific ◽

Fab Fragments ◽

Cluster Label ◽

Covalently Linked ◽

Texas Red ◽

Fold Excess

Two new types of covalently linked, site-specific immunoprobes have been prepared using metal cluster labels, and used to stain components of cells. Combined fluorescein and 1.4 nm “Nanogold” labels were prepared by using the fluorescein-conjugated tris (aryl) phosphine ligand and the amino-substituted ligand in the synthesis of the Nanogold cluster. This cluster label was activated by reaction with a 60-fold excess of (sulfo-Succinimidyl-4-N-maleiniido-cyclohexane-l-carboxylate (sulfo-SMCC) at pH 7.5, separated from excess cross-linking reagent by gel filtration, and mixed in ten-fold excess with Goat Fab’ fragments against mouse IgG (obtained by reduction of F(ab’)2 fragments with 50 mM mercaptoethylamine hydrochloride). Labeled Fab’ fragments were isolated by gel filtration HPLC (Superose-12, Pharmacia). A combined Nanogold and Texas Red label was also prepared, using a Nanogold cluster derivatized with both and its protected analog: the cluster was reacted with an eight-fold excess of Texas Red sulfonyl chloride at pH 9.0, separated from excess Texas Red by gel filtration, then deprotected with HC1 in methanol to yield the amino-substituted label.

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Electron microscopy and diffraction of crystalline dendrimers and macrocycles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151921 ◽

1993 ◽

Vol 51 ◽

pp. 1218-1219

Author(s):

C. J. Buchko ◽

P. M. Wilson ◽

Z. Xu ◽

J. Zhang ◽

S. Lee ◽

...

Keyword(s):

Electron Microscopy ◽

Liquid Crystalline ◽

Structural Information ◽

High Resolution Electron Microscopy ◽

Scanning Calorimetry ◽

Tertiary Butyl ◽

Phenyl Acetylene ◽

Selected Area Electron Diffraction ◽

Liquid Crystalline Phases ◽

Resolution Electron

The synthesis of well-defined organic molecules with unique geometries opens new opportunities for understanding and controlling the organization of condensed matter. Here, we study dendrimers and macrocycles which are synthesized from rigid phenyl-acetylene spacer units, Both units are solubilized by the presence of tertiary butyl groups located at the periphery of the molecule. These hydrocarbon materials form crystalline and liquid crystalline phases which have been studied by differential scanning calorimetry, hot stage optical microscopy, and wide-angle x-ray scattering (WAXS).The precisely defined architecture of these molecules makes it possible to investigate systematic variations in chemical architecture on the nature of microstructural organization. Here we report on the transmission electron microscopy (TEM), selected area electron diffraction (SAED), and high resolution electron microscopy (HREM) studies of crystalline thin films formed by deposition of these materials onto carbon substrates from dilute solution. Electron microscopy is very attractive for gaining structural information on new molecules due to the scarcity of material to grow single crystals suitable for conventional crystallography.

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The challenge of detecting modifications on proteins

Essays in Biochemistry ◽

10.1042/ebc20190055 ◽

2020 ◽

Vol 64 (1) ◽

pp. 135-153 ◽

Cited By ~ 1

Author(s):

Lauren Elizabeth Smith ◽

Adelina Rogowska-Wrzesinska

Keyword(s):

Mass Spectrometry ◽

Protein Function ◽

Chemical Properties ◽

Lysine Acetylation ◽

Mass Determination ◽

Post Translational Modifications ◽

Site Specific ◽

The Common

Abstract Post-translational modifications (PTMs) are integral to the regulation of protein function, characterising their role in this process is vital to understanding how cells work in both healthy and diseased states. Mass spectrometry (MS) facilitates the mass determination and sequencing of peptides, and thereby also the detection of site-specific PTMs. However, numerous challenges in this field continue to persist. The diverse chemical properties, low abundance, labile nature and instability of many PTMs, in combination with the more practical issues of compatibility with MS and bioinformatics challenges, contribute to the arduous nature of their analysis. In this review, we present an overview of the established MS-based approaches for analysing PTMs and the common complications associated with their investigation, including examples of specific challenges focusing on phosphorylation, lysine acetylation and redox modifications.

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