scholarly journals In Situ Real-Time TEM Reveals Growth, Transformation and Function in One-Dimensional Nanoscale Materials: From a Nanotechnology Perspective

2013 ◽  
Vol 2013 ◽  
pp. 1-21 ◽  
Author(s):  
Nikolay Petkov
Keyword(s):  
Real Time ◽  
Building Blocks ◽  
Semiconductor Nanowires ◽  
One Dimensional ◽  
Operation Conditions ◽  
Recent Developments ◽  
And Function ◽  
Physical Phenomena ◽  
Fundamental Physical

This paper summarises recent developments in in situ TEM instrumentation and operation conditions. The focus of the discussion is on demonstrating how improved understanding of fundamental physical phenomena associated with nanowire or nanotube materials, revealed by following transformations in real time and high resolution, can assist the engineering of emerging electronic and optoelectronic devices. Special attention is given to Si, Ge, and compound semiconductor nanowires and carbon nanotubes (CNTs) as one of the most promising building blocks for devices inspired by nanotechnology.

Progress in environmental high-voltage transmission electron microscopy for nanomaterials

2020 ◽  
Vol 378 (2186) ◽  
pp. 20190602
Author(s):  
Nobuo Tanaka ◽  
Takeshi Fujita ◽  
Yoshimasa Takahashi ◽  
Jun Yamasaki ◽  
Kazuyoshi Murata ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Voltage ◽  
High Energy ◽  
Transmission Electron ◽  
Recent Developments ◽  
In Situ Observations ◽  
High Voltage Transmission ◽  
And Function

A new environmental high-voltage transmission electron microscope (E-HVEM) was developed by Nagoya University in collaboration with JEOL Ltd. An open-type environmental cell was employed to enable in-situ observations of chemical reactions on catalyst particles as well as mechanical deformation in gaseous conditions. One of the reasons for success was the application of high-voltage transmission electron microscopy to environmental (in-situ) observations in the gas atmosphere because of high transmission of electrons through gas layers and thick samples. Knock-on damages to samples by high-energy electrons were carefully considered. In this paper, we describe the detailed design of the E-HVEM, recent developments and various applications. This article is part of a discussion meeting issue ‘Dynamic in situ microscopy relating structure and function'.

REALTIME GEO-REFERENCED DETECTION OF DISPERSED OIL PLUMES

2005 ◽  
Vol 2005 (1) ◽  
pp. 693-696 ◽  
Author(s):  
Christopher B. Fuller ◽  
James S. Bonner ◽  
Frank Kelly ◽  
Cheryl A. Page ◽  
Temitope Ojo
Keyword(s):  
Real Time ◽  
Coast Guard ◽  
Ex Situ ◽  
Environmental Research ◽  
Time Lags ◽  
Corpus Christi ◽  
Dispersed Oil ◽  
Recent Developments ◽  
The U.S

The current SMART protocol used by the U.S. Coast Guard relies on traditional ex-situ fluorometers that require physical transport of the sample from the water column to the instruments. While sample transport methods are available (e.g. pumps and discrete sampling), they introduce time lags in the data acquisition process. These lags can be a source of error when the data is post analyzed and is not conducive to real-time monitoring efforts, creating significant logistical problems and dispersion (smearing) of the sample stream. Another limitation of the currently-used equipment is that it requires much attention to manually record GPS data which is later used to determine the spatial distribution of an oil plume. Recent developments of in-situ fluorometric instrumentation promise to simplify problems associated with deployment of ex-situ instrumentation (e.g. insuring that pumps are primed) in boat-based field applications. This study first compares the performance of two in-situ fluorometers in a simulated oil and dispersant application at the Shoreline Environmental Research Facility at Texas A&M University in Corpus Christi, Texas. The fluorometers were the WETStar and the ECP-FL3 (both by WETLabs, Inc.). To address issues related to data collection from a GPS and a fluorometer, a system was developed that simultaneously merges data from both instruments into a single file and presents the data real-time as a color-coded ship track. The applicability of this system was tested and evaluated during a spill response exercise conducted by the Texas General Land Office and the U.S. Coast Guard in Galveston Bay, Texas, U.S.A.

Neurocartography: Geometry and Biology of the Central Nervous System

1997 ◽  
Vol 3 (S2) ◽  
pp. 295-296
Author(s):  
O. J. Tretiak ◽  
J. Nissanov
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Brain Function ◽  
Spatial Organization ◽  
Mrna In Situ Hybridization ◽  
Functional Images ◽  
Recent Developments ◽  
The Central Nervous System ◽  
And Function

The central nervous system of a vertebrate organism exhibits a very complex spatial organization structure and function. These relationships are the subject of intense study for over a century, and recent developments in imaging have attracted ever increasing effort devoted to the understanding of brain function. One can produce any number of quantitative images that provide maps of the anatomy and function of nerve tissues. For example, autoradiography can yield functional images (2-deoxy glucose), maps of neurotransmitters receptors (over 100 know types), and gene expression labeled with complementary mRNA (in-situ hybridization). Immunohistochemistry produces maps of a large variety of neuroactive components, such as transmitters.To illustrate a typical procedure, we describe the mapping of brain function with 2-deoxy glucose (2DG). A rat performing some task is injected with a solution of 2DG radiolabeled with 14C¨ Subsequently, the animal is sacrificed, the brain is cryosectioned (ca. 20 μm), and contact autoradio-grams of these sections are made on X-ray film.

scholarly journals Spontaneous Aminolytic Cyclization and Self-Assembly of Dipeptide Methyl Esters in Water

2020 ◽  
Author(s):  
Charalampos Pappas ◽  
Nadeesha Wijerathne ◽  
Jugal Kishore Sahoo ◽  
Ankit Jain ◽  
Daniela Kroiss ◽  
...  
Keyword(s):  
Self Assembly ◽  
Chemical Nature ◽  
Methyl Esters ◽  
Building Blocks ◽  
Short Peptides ◽  
Cyclic Dipeptides ◽  
Spontaneous Formation ◽  
And Function ◽  
Cooperative Assembly

Dipeptides are known to spontaneously cyclize to diketopiperazines, and in some cases these cyclic dipeptides have been shown to self-assemble to form supramolecular nanostructures.<b> </b>Herein, we demonstrate the <i>in situ</i> cyclization of dipeptide methyl esters in aqueous buffer by intramolecular aminolysis, leading to the formation of diverse supramolecular nanostructures. The chemical nature of the amino acid side chains dictates the supramolecular arrangement and resulting nanoscale architectures. For c[LF], supramolecular gels are formed, and the concentration of starting materials influences the mechanical properties of hydrogels. Moreover, by adding metalloporphyrin to the starting dipeptide ester solution, these become incorporated through cooperative assembly,<b> </b>resulting in the formation of nanofibers able to catalyse the oxidation of organic phenol in water. The approach taken here, which combines the chemically activated assembly with the versatility of short peptides might pave the way for achieving the spontaneous formation of supramolecular order and function using simple building blocks.<br>

scholarly journals Spontaneous Aminolytic Cyclization and Self-Assembly of Dipeptide Methyl Esters in Water

2020 ◽  
Author(s):  
Charalampos Pappas ◽  
Nadeesha Wijerathne ◽  
Jugal Kishore Sahoo ◽  
Ankit Jain ◽  
Daniela Kroiss ◽  
...  
Keyword(s):  
Self Assembly ◽  
Chemical Nature ◽  
Methyl Esters ◽  
Building Blocks ◽  
Short Peptides ◽  
Cyclic Dipeptides ◽  
Spontaneous Formation ◽  
And Function ◽  
Cooperative Assembly

Dipeptides are known to spontaneously cyclize to diketopiperazines, and in some cases these cyclic dipeptides have been shown to self-assemble to form supramolecular nanostructures.<b> </b>Herein, we demonstrate the <i>in situ</i> cyclization of dipeptide methyl esters in aqueous buffer by intramolecular aminolysis, leading to the formation of diverse supramolecular nanostructures. The chemical nature of the amino acid side chains dictates the supramolecular arrangement and resulting nanoscale architectures. For c[LF], supramolecular gels are formed, and the concentration of starting materials influences the mechanical properties of hydrogels. Moreover, by adding metalloporphyrin to the starting dipeptide ester solution, these become incorporated through cooperative assembly,<b> </b>resulting in the formation of nanofibers able to catalyse the oxidation of organic phenol in water. The approach taken here, which combines the chemically activated assembly with the versatility of short peptides might pave the way for achieving the spontaneous formation of supramolecular order and function using simple building blocks.<br>

Engineering Protein and Peptide Building Blocks for Nanotechnology

2007 ◽  
Vol 7 (2) ◽  
pp. 387-401 ◽  
Author(s):  
Scott Banta ◽  
Zaki Megeed ◽  
Monica Casali ◽  
Kaushal Rege ◽  
Martin L. Yarmush
Keyword(s):  
Molecular Motors ◽  
Building Blocks ◽  
Biological Synthesis ◽  
Computational Techniques ◽  
Structural Elements ◽  
Short Discussion ◽  
Safety Issues ◽  
Recent Developments ◽  
And Function ◽  
Proteins And Peptides

The tremendous diversity in the structure and function of proteins has stimulated intense interest in using them for nanotechnology applications. In this review, we discuss recent developments in the engineering of proteins and peptides for the design and construction of functional and structural elements of nanodevices. We begin with a short discussion highlighting the differences between chemical and biological synthesis of proteins and peptides. Subsequently, we review recent applications of proteins and peptides as molecular motors, transducers, biosensors, and structural elements of nanodevices. We supplement this review with highlights of our own work in the areas of peptide-based transducers for stand-alone and intra-molecular applications. This is followed by a short discussion of nanotechnology safety issues, and how proteins and peptides may enable the development of biocompatible nanomaterials. The future outlook for protein and peptide-based nanomaterials is then discussed, with an eye toward the significant impact of improved computational techniques on the field.

scholarly journals pH-Triggered self-assembly and hydrogelation of cyclic peptide nanotubes confined in water micro-droplets

2018 ◽  
Vol 3 (4) ◽  
pp. 391-396 ◽  
Author(s):  
Alejandro Méndez-Ardoy ◽  
Juan R. Granja ◽  
Javier Montenegro
Keyword(s):  
Self Assembly ◽  
Cyclic Peptide ◽  
Polymer Networks ◽  
Building Blocks ◽  
One Dimensional ◽  
Confined Spaces ◽  
Cyclic Peptide Nanotubes ◽  
Supramolecular Polymerization ◽  
Fundamental Physical ◽  
Physical Principles

The controlled one-dimensional supramolecular polymerization of synthetic building blocks in confined spaces constitutes a key challenge to simplify the understanding of the fundamental physical principles behind the behavior of more complex encapsulated polymer networks.

scholarly journals Data on making uniform lignin building blocks via in-situ real-time monitoring of hydroxyethyl modification

Data in Brief ◽  
2020 ◽  
Vol 33 ◽  
pp. 106512
Author(s):  
Li-Yang Liu ◽  
Kim Bessler ◽  
Siwei Chen ◽  
Mijung Cho ◽  
Qi Hua ◽  
...  
Keyword(s):  
Real Time ◽  
Building Blocks ◽  
Real Time Monitoring

In-Situ Observation Selection for Quality Management in Metal Additive Manufacturing

2021 ◽  
Author(s):  
Byeong-Min Roh ◽  
Soundar R. T. Kumara ◽  
Hui Yang ◽  
Timothy W. Simpson ◽  
Paul Witherell ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Real Time ◽  
Sensor Data ◽  
Metal Additive Manufacturing ◽  
Part Quality ◽  
Process Outcomes ◽  
Physical Phenomena ◽  
The Relationship ◽  
Metal Additive

Abstract Metal additive manufacturing (MAM) provides a larger design space with accompanying manufacturability than traditional manufacturing. Recently, much research has focused on simulating the MAM process with regards to part geometry, porosity, and microstructure properties. Despite continued advances, MAM processes have many variables that are not well understood with respect to their effect on the part quality. With the common use of in-situ sensors — such as CMOS cameras and infrared cameras — numerous, real-time datasets can be captured and analyzed for monitoring both the process and the part. However, currently, real-time data predominantly focuses on the build failure and process anomalies by capturing the printing defects (cracks/peel-off). A large amount of data — such as melt pool geometries and temperature gradients — are just beginning to be explored, along with their connections to final part quality. Towards investigating these connections, in this paper we propose models that capture numerous sensor capabilities and associate them with the corresponding, real-time, physical phenomena. These sensor models lay the foundation for a comprehensive, knowledge framework that forms the basis for quality monitoring and management of MAM process outcomes. Using our previously developed process ontology model [1–3], which describes the relationship between process variables and process outcomes, we can discover the relationship between the real-time, physical phenomena and the deviations in the targeted, build quality. For example, statistically significant sensor data that predicts deviations from targeted process qualities can be detected and used to control the process parameters. Case studies that scope the physical phenomena and sensor data are provided for verifying the effectiveness and efficiency of the proposed qualification and certification models.

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