High performance Raman spectroscopy with simple optical components

2010 ◽  
Vol 78 (7) ◽  
pp. 671-677 ◽  
Author(s):  
W. R. C. Somerville ◽  
E. C. Le Ru ◽  
P. T. Northcote ◽  
P. G. Etchegoin
Crystals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 235
Author(s):  
Shuqi Zhao ◽  
Tongtong Yu ◽  
Ziming Wang ◽  
Shilei Wang ◽  
Limei Wei ◽  
...  

Two-dimensional (2D) materials driven by their unique electronic and optoelectronic properties have opened up possibilities for their various applications. The large and high-quality single crystals are essential to fabricate high-performance 2D devices for practical applications. Herein, IV-V 2D GeP single crystals with high-quality and large size of 20 × 15 × 5 mm3 were successfully grown by the Bi flux growth method. The crystalline quality of GeP was confirmed by high-resolution X-ray diffraction (HRXRD), Laue diffraction, electron probe microanalysis (EPMA) and Raman spectroscopy. Additionally, intrinsic anisotropic optical properties were investigated by angle-resolved polarized Raman spectroscopy (ARPRS) and transmission spectra in detail. Furthermore, we fabricated high-performance photodetectors based on GeP, presenting a relatively large photocurrent over 3 mA. More generally, our results will significantly contribute the GeP crystal to the wide optoelectronic applications.


Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1246
Author(s):  
Steffen Ulitzsch ◽  
Tim Bäuerle ◽  
Mona Stefanakis ◽  
Marc Brecht ◽  
Thomas Chassé ◽  
...  

We present the modification of ethylene-propylene rubber (EPM) with vinyltetra-methydisiloxane (VTMDS) via reactive extrusion to create a new silicone-based material with the potential for high-performance applications in the automotive, industrial and biomedical sectors. The radical-initiated modification is achieved with a peroxide catalyst starting the grafting reaction. The preparation process of the VTMDS-grafted EPM was systematically investigated using process analytical technology (in-line Raman spectroscopy) and the statistical design of experiments (DoE). By applying an orthogonal factorial array based on a face-centered central composite experimental design, the identification, quantification and mathematical modeling of the effects of the process factors on the grafting result were undertaken. Based on response surface models, process windows were defined that yield high grafting degrees and good grafting efficiency in terms of grafting agent utilization. To control the grafting process in terms of grafting degree and grafting efficiency, the chemical changes taking place during the modification procedure in the extruder were observed in real-time using a spectroscopic in-line Raman probe which was directly inserted into the extruder. Successful grafting of the EPM was validated in the final product by 1H-NMR and FTIR spectroscopy.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Bishwajeet Singh Bhardwaj ◽  
Takeshi Sugiyama ◽  
Naoko Namba ◽  
Takayuki Umakoshi ◽  
Takafumi Uemura ◽  
...  

Abstract Pentacene, an organic molecule, is a promising material for high-performance field effect transistors due to its high charge carrier mobility in comparison to usual semiconductors. However, the charge carrier mobility is strongly dependent on the molecular orientation of pentacene in the active layer of the device, which is hard to investigate using standard techniques in a real device. Raman scattering, on the other hand, is a high-resolution technique that is sensitive to the molecular orientation. In this work, we investigated the orientation distribution of pentacene molecules in actual transistor devices by polarization-dependent Raman spectroscopy and correlated these results with the performance of the device. This study can be utilized to understand the distribution of molecular orientation of pentacene in various electronic devices and thus would help in further improving their performances.


2020 ◽  
Vol 7 (3) ◽  
pp. 191949 ◽  
Author(s):  
Amy Courtney ◽  
Luke M. Alvey ◽  
George O. T. Merces ◽  
Niamh Burke ◽  
Mark Pickering

With technologies rapidly evolving, many research institutions are now opting to invest in costly, high-quality, specialized microscopes which are shared by many researchers. As a consequence, the user may not have the ability to adapt a microscope to their specific needs and limitations in experimental design are introduced. A flexible work-horse microscopy system is a valuable tool in any laboratory to meet the diverse needs of a research team and promote innovation in experimental design. We have developed the Flexiscope; a multi-functional, adaptable, efficient and high-performance microscopy/electrophysiology system for everyday applications in a neurobiology laboratory. The core optical components are relatively constant in the three configurations described here: an upright configuration, an inverted configuration and an upright/electrophysiology configuration. We have provided a comprehensive description of the Flexiscope. We show that this method is capable of oblique infrared illumination imaging, multi-channel fluorescent imaging and automated three-dimensional scanning of larger specimens. Image quality is conserved across the three configurations of the microscope, and conversion between configurations is possible quickly and easily, while the motion control system can be repurposed to allow sub-micrometre computer-controlled micromanipulation. The Flexiscope provides similar performance and usability to commercially available systems. However, as it can be easily reconfigured for multiple roles, it can remove the need to purchase multiple microscopes, giving significant cost savings. The modular reconfigurable nature allows the user to customize the system to their specific needs and adapt/upgrade the system as challenges arise, without requiring specialized technical skills.


2019 ◽  
Vol 5 (1) ◽  
pp. 469-471
Author(s):  
Thomas Reske ◽  
Katharina Wulf ◽  
Thomas Eickner ◽  
Niels Grabow ◽  
Klaus-Peter Schmitz ◽  
...  

AbstractThe analysis of device drug content typically is carried out by means of chromatographic methods such as high performance liquid chromatography (HPLC) or liquid chromatography-mass spectrometry (LCMS). These approved methods are particularly fast, cost-efficient and ubiquitous in chemical-analytical laboratories. However, these quantitative methods necessitate the drug being eluted, which represents a destructive process. A novel alternative to these well-established methods [1, 2] is the Raman spectroscopy, which is fast and cost-efficient, as well [3]. Additionally, it offers the advantage of nondestructive analysis without the need for a special sample preparation. Within the current investigation we applied Raman spectroscopy for the qualitative and quantitative analysis of dexamethasone (DMS), a glucocorticoid, incorporated in a silicone matrix. The investigation was conducted in a rectangular area on the sample surface. The required number of measuring points (spectra) was determined. Calibration was performed with samples containing different amounts of DMS. The evaluation of Raman spectra is based on the analysis of the peak areas of the bands at 795 rel. cm-1(silicone) and 1,663 rel. cm-1(DMS). Remarkably, next to a precise overview of DMS distribution, an exact and reproducible quantification of incorporated DMS could be obtained.


RSC Advances ◽  
2015 ◽  
Vol 5 (115) ◽  
pp. 94849-94854 ◽  
Author(s):  
Youju Huang ◽  
Palanisamy Kannan ◽  
Lei Zhang ◽  
Yun Rong ◽  
Liwei Dai ◽  
...  

An island like array of tiny Ag nanoparticles bounded on triangular Au nanoplates was synthesized as surface-enhanced Raman spectroscopy substrate.


2010 ◽  
Vol 81 (5) ◽  
pp. 053111 ◽  
Author(s):  
Matthieu Paillet ◽  
François Meunier ◽  
Marc Verhaegen ◽  
Sébastien Blais-Ouellette ◽  
Richard Martel

2001 ◽  
Vol 32 (12) ◽  
pp. 983-988 ◽  
Author(s):  
P. Matousek ◽  
M. Towrie ◽  
C. Ma ◽  
W. M. Kwok ◽  
D. Phillips ◽  
...  

2014 ◽  
Vol 281 (1788) ◽  
pp. 20140806 ◽  
Author(s):  
Daniel B. Thomas ◽  
Kevin J. McGraw ◽  
Michael W. Butler ◽  
Matthew T. Carrano ◽  
Odile Madden ◽  
...  

The broad palette of feather colours displayed by birds serves diverse biological functions, including communication and camouflage. Fossil feathers provide evidence that some avian colours, like black and brown melanins, have existed for at least 160 million years (Myr), but no traces of bright carotenoid pigments in ancient feathers have been reported. Insight into the evolutionary history of plumage carotenoids may instead be gained from living species. We visually surveyed modern birds for carotenoid-consistent plumage colours (present in 2956 of 9993 species). We then used high-performance liquid chromatography and Raman spectroscopy to chemically assess the family-level distribution of plumage carotenoids, confirming their presence in 95 of 236 extant bird families (only 36 family-level occurrences had been confirmed previously). Using our data for all modern birds, we modelled the evolutionary history of carotenoid-consistent plumage colours on recent supertrees. Results support multiple independent origins of carotenoid plumage pigmentation in 13 orders, including six orders without previous reports of plumage carotenoids. Based on time calibrations from the supertree, the number of avian families displaying plumage carotenoids increased throughout the Cenozoic, and most plumage carotenoid originations occurred after the Miocene Epoch (23 Myr). The earliest origination of plumage carotenoids was reconstructed within Passeriformes, during the Palaeocene Epoch (66–56 Myr), and not at the base of crown-lineage birds.


Sign in / Sign up

Export Citation Format

Share Document