Tribological Properties of Wax on Different Trees Leaf Surface Containing Different Chemical Components

Abstract Three kinds of leaf-surface waxes were extracted from different trees, and their chemical compositions were analyzed by Gas Chromatography-Mass Spectrometer (GC-MS). A MFT-R4000 tester was employed to investigate the tribological performances of samples, and the Scanning Electron Microscope (SEM) and Time of Flight Secondary Ion Mass Spectrometry (TOF-SIMS) were used to characterize the morphologies and chemical compositions on the worn surfaces, respectively. The result showed that waxes can effectively improve the friction reduction and anti-wear abilities of base oil, and different composition of waxes have different improve degree. This can be attributed to the chemical compositions and degree of chemical action.

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Uncoated Lvsem and Imaging Tof-Sims of Unfixed, Plunge Frozen, Freeze Dried, Fungal and Plant Material

Microscopy and Microanalysis ◽

10.1017/s1431927600024375 ◽

1998 ◽

Vol 4 (S2) ◽

pp. 850-851

Author(s):

E. J. Basgall ◽

N. Winograd

Keyword(s):

Freeze Drying ◽

Secondary Ion Mass Spectrometry ◽

Low Voltage ◽

Ion Beam ◽

Chemical Compositions ◽

Tof Sims ◽

Freeze Dried ◽

Structural Preservation ◽

Secondary Ion

A Cryosorption Freeze Drying (CFD) system was evaluated for its effectiveness in preparing delicate biological materials for both low voltage-field emission scanning electron microscopy (LVFESEM) and imaging liquid metal (Ga) ion beam, static time-of-flight, secondary ion mass spectrometry (TOF-SIMS). The primary goals of these studies were to investigate the retention of both structural and chemical integrity using fresh cryoprepared biological material which had not been exposed to any chemical fixation and which would not be coated by any conductive material in order to obtain information from the native surfaces. Duplicate chemically fixed samples were processed for comparison. LV-FESEM (2-2.5kV) was used to assess the quality of the structural preservation of the freezing and freeze drying (FD) protocols. Imaging static TOF-SIMS was used to investigate the surface chemical compositions of the biological samples.

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Applications of Time-OF-Flight Secondary Ion Mass Spectrometry (TOF-SIMS)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135149 ◽

1990 ◽

Vol 48 (2) ◽

pp. 308-309

Author(s):

Bruno Schueler ◽

Robert W. Odom

Keyword(s):

Mass Spectrometry ◽

Secondary Ion Mass Spectrometry ◽

Structural Information ◽

Time Of Flight ◽

Biological Tissues ◽

Polymer Surfaces ◽

Tof Sims ◽

Secondary Ions ◽

Ion Mass Spectrometry ◽

Secondary Ion

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) provides unique capabilities for elemental and molecular compositional analysis of a wide variety of surfaces. This relatively new technique is finding increasing applications in analyses concerned with determining the chemical composition of various polymer surfaces, identifying the composition of organic and inorganic residues on surfaces and the localization of molecular or structurally significant secondary ions signals from biological tissues. TOF-SIMS analyses are typically performed under low primary ion dose (static SIMS) conditions and hence the secondary ions formed often contain significant structural information.This paper will present an overview of current TOF-SIMS instrumentation with particular emphasis on the stigmatic imaging ion microscope developed in the authors’ laboratory. This discussion will be followed by a presentation of several useful applications of the technique for the characterization of polymer surfaces and biological tissues specimens. Particular attention in these applications will focus on how the analytical problem impacts the performance requirements of the mass spectrometer and vice-versa.

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Optics-Free Visualization of Proteins in Single Cells by Time of Flight-Secondary Ion Mass Spectrometry Coupled with Genetically Encoded Chemical Tags

10.26434/chemrxiv.12046125 ◽

2020 ◽

Author(s):

Feifei Jia ◽

Jie Wang ◽

Yanyan Zhang ◽

Qun Luo ◽

Luyu Qi ◽

...

Keyword(s):

Mass Spectrometry ◽

Secondary Ion Mass Spectrometry ◽

Single Cells ◽

Time Of Flight ◽

E Coli ◽

Tof Sims ◽

Ion Mass Spectrometry ◽

Chemical Tags ◽

Secondary Ion

In situ visualization of proteins of interest at single cell level is attractive in cell biology, molecular biology and biomedicine, which usually involves photon, electron or X-ray based imaging methods. Herein, we report an optics-free strategy that images a specific protein in single cells by time of flight-secondary ion mass spectrometry (ToF-SIMS) following genetic incorporation of fluorine-containing unnatural amino acids as a chemical tag into the protein via genetic code expansion technique. The method was developed and validated by imaging GFP in E. coli and human HeLa cancer cells, and then utilized to visualize the distribution of chemotaxis protein CheA in E. coli cells and the interaction between high mobility group box 1 protein and cisplatin damaged DNA in HeLa cells. The present work highlights the power of ToF-SIMS imaging combined with genetically encoded chemical tags for in situ visualization of proteins of interest as well as the interactions between proteins and drugs or drug damaged DNA in single cells.

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