scholarly journals Expanding the monomer scope of linear and branched vinyl polymerisations via copper-catalysed reversible-deactivation radical polymerisation of hydrophobic methacrylates using anhydrous alcohol solvents

2019 ◽  
Vol 10 (37) ◽  
pp. 5103-5115 ◽  
Author(s):  
Sean Flynn ◽  
Andrew B. Dwyer ◽  
Pierre Chambon ◽  
Steve Rannard
Keyword(s):  
Anhydrous Alcohol ◽  
Wide Range ◽  
Reversible Deactivation ◽  
Radical Polymerisation ◽  
Alcohol Solvents

The use of anhydrous alcohols for Cu-catalysed reversible-deactivation radical polymerisation of a wide range of hydrophobic methacrylates has been explored in detail.

Fair Attribution of Functional Contribution in Artificial and Biological Networks

2004 ◽  
Vol 16 (9) ◽  
pp. 1887-1915 ◽  
Author(s):  
Alon Keinan ◽  
Ben Sandbank ◽  
Claus C. Hilgetag ◽  
Isaac Meilijson ◽  
Eytan Ruppin
Keyword(s):  
Biological Networks ◽  
Computational Models ◽  
Successful Operation ◽  
Value Analysis ◽  
Causal Function ◽  
Wide Range ◽  
Reversible Deactivation ◽  
Potential Applications ◽  
Neurophysiological Model ◽  
Insight Into

This letter presents the multi-perturbation Shapley value analysis (MSA), an axiomatic, scalable, and rigorous method for deducing causal function localization from multiple perturbations data. The MSA, based on fundamental concepts from game theory, accurately quantifies the contributions of network elements and their interactions, overcoming several shortcomings of previous function localization approaches. Its successful operation is demonstrated in both the analysis of a neurophysiological model and of reversible deactivation data. The MSA has a wide range of potential applications, including the analysis of reversible deactivation experiments, neuronal laser ablations, and transcranial magnetic stimulation “virtual lesions”, as well as in providing insight into the inner workings of computational models of neurophysiological systems.

scholarly journals Returnable baking waste — a new type of raw materials for distillates production (Part III. Distillation stage)

Food systems ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 89-96
Author(s):  
L. N. Krikunova ◽  
E. V. Dubinina ◽  
S. Yu. Makarov
Keyword(s):  
Mass Concentration ◽  
Volume Fraction ◽  
Raw Materials ◽  
Alcoholic Beverage ◽  
Volatile Components ◽  
Physicochemical Composition ◽  
Anhydrous Alcohol ◽  
Wide Range ◽  
New Type ◽  
Distillate Fractions

The distillation stage is a key step in distillate-based alcoholic beverage technology. The use of a new non-traditional type of raw materials to obtain distillates requires comprehensive research. The purpose of this work was to study the processes at the distillation stage of the discharged wort from the recyclable baking waste, in identifying significant factors and determining the optimal technological values of these factors. The objects of the study served 9 samples of fermented wort from various types of recyclable baking waste, distillate fractions and samples of distillates. The distillation was performed on the installation of direct distillation “KOTHE DESTILLATIONSTECHNIK” (Germany). In the objects of the study, the volume, the volume fraction of ethyl alcohol and the mass concentration of the main volatile components were determined. The composition and concentration of basic volatile components were determined using gas chromatography on the device “Thermo Trace GC Ultra” (Thermo, United States). The wide range of variation of the mass concentration of the main volatile components, depending on the composition of the initial raw materials, is revealed. It has been established that the nature of the distribution of volatile components according to distillate fractions does not depend on the physicochemical composition of the fermented wort from different types of recyclable baking waste. It is shown that the nature of the distribution of volatile components according to fractions in obtaining a distillate from the recyclable baking waste has certain differences from their distribution in the preparation of cognac and fruit distillates. A comparative assessment of distillates obtained by single fractionated distillation and double distillation showed the advantage of the first alcohol output and the composition of volatile components. It has been established that the distillation rate with a direct fractionated has a significant effect on the dynamics of the distribution of the main volatile components and the output of the distillate for anhydrous alcohol. With an optimal distillation rate (5.9 cm3 / min), an anhydrous alcohol output increases, on average, by 4% and reduced the losses of valuable aroma-forming volatile components with head and tail fractions.

scholarly journals Determining the effect of side reactions on product distributions in RAFT polymerization by MALDI-TOF MS

2015 ◽  
Vol 6 (30) ◽  
pp. 5437-5450 ◽  
Author(s):  
Antonio Veloso ◽  
Wendy García ◽  
Amaia Agirre ◽  
Nicholas Ballard ◽  
Fernando Ruipérez ◽  
...  
Keyword(s):  
Radical Polymerization ◽  
Raft Polymerization ◽  
Side Reactions ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Product Distributions ◽  
Wide Range ◽  
Reversible Deactivation ◽  
Reversible Deactivation Radical Polymerization ◽  
Tof Ms

RAFT polymerization has emerged as one of the most versatile reversible deactivation radical polymerization techniques and is capable of polymerizing a wide range of monomers under various conditions.

Computational Evaluation of the Sulfonyl Radical as a Universal Leaving Group for RAFT Polymerisation

2013 ◽  
Vol 66 (3) ◽  
pp. 308 ◽  
Author(s):  
Ganna Gryn'ova ◽  
Tamaz Guliashvili ◽  
Krzysztof Matyjaszewski ◽  
Michelle L. Coote
Keyword(s):  
Chain Transfer ◽  
Superior Performance ◽  
Experimental Conditions ◽  
Computational Evaluation ◽  
Reversible Addition ◽  
Wide Range ◽  
Leaving Group ◽  
Radical Polymerisation ◽  
Synthetic Routes ◽  
High Level

The present study investigates the performance of the sulfonyl radical, i.e. •SO2Ph, as a universal leaving group in reversible addition–fragmentation chain-transfer (RAFT) polymerisation. The sulfonyl radical is widely used as a radical initiator and has already been proved successful as a leaving group in an atom-transfer radical polymerisation. Our results, obtained using high-level ab initio computational methodology under relevant experimental conditions, indicate superior performance of the sulfonyl compared with a reference cyanoisopropyl group in controlling RAFT of a wide range of monomers. Importantly, the presence of sulfonyl chain ends in the polymers so formed opens attractive possibilities for further functionalisation. Potential synthetic routes to the R-sulfonyl RAFT agents are discussed.

Reversible-Deactivation Radical Polymerisation: chain polymerisation made simple

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ali Bagheri ◽  
Suzanne Boniface ◽  
Christopher M. Fellows
Keyword(s):  
Secondary Education ◽  
Chemical Reaction ◽  
Tertiary Education ◽  
The Past ◽  
One Stage ◽  
Stage Of Development ◽  
Reversible Deactivation ◽  
Radical Polymerisation

Abstract Reversible-Deactivation Radical Polymerisation (RDRP) is one of the most exciting developments in chemistry over the past few decades, but it is rarely mentioned when polymerisation mechanisms are introduced in the final years of secondary education or first years of tertiary education. We propose that this is unfortunate, as RDRP is simpler than conventional Radical Polymerisation both conceptually and in terms of setting quantitative problems, and that it illustrates several other important features of chemistry as a human endeavour: How essential mechanistic unities are hidden by the details of how we write a chemical reaction, how a ‘bug’ in one stage of development of a process can become a ‘feature’ in a later stage, and how exciting changes can occur quite suddenly in fields thought to be mature and uninteresting.

Recent Applications of High Resolution Electron Microscopy to Crystalline Arrays of Virus Particles

1978 ◽  
Vol 36 (3) ◽  
pp. 470-482 ◽  
Author(s):  
R.W. Horne
Keyword(s):  
Electron Microscopy ◽  
Image Processing ◽  
Analytical Techniques ◽  
Staining Technique ◽  
High Resolution Electron Microscopy ◽  
Optical Diffraction ◽  
Full Potential ◽  
Virus Particles ◽  
Resolution Electron ◽  
Wide Range

The technique of surrounding virus particles with a neutralised electron dense stain was described at the Fourth International Congress on Electron Microscopy, Berlin 1958 (see Home & Brenner, 1960, p. 625). For many years the negative staining technique in one form or another, has been applied to a wide range of biological materials. However, the full potential of the method has only recently been explored following the development and applications of optical diffraction and computer image analytical techniques to electron micrographs (cf. De Hosier & Klug, 1968; Markham 1968; Crowther et al., 1970; Home & Markham, 1973; Klug & Berger, 1974; Crowther & Klug, 1975). These image processing procedures have allowed a more precise and quantitative approach to be made concerning the interpretation, measurement and reconstruction of repeating features in certain biological systems.

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

Application of TEM to Deformation, Wear, and Fracture of Ceramics

1974 ◽  
Vol 32 ◽  
pp. 472-473
Author(s):  
B. J. Hockey
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Mechanical Behavior ◽  
Brittle Materials ◽  
High Temperature Strength ◽  
Wide Range ◽  
Corrosive Environments ◽  
Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

Observation of Atom Rows in Thorium Pyromellitate Using a Field Emission STEM

1977 ◽  
Vol 35 ◽  
pp. 80-81
Author(s):  
H. Todokoro ◽  
S. Nomura ◽  
T. Komoda
Keyword(s):  
Field Emission ◽  
Amorphous Carbon ◽  
Carbon Film ◽  
Dark Field Image ◽  
Dark Field ◽  
Amorphous Carbon Film ◽  
Atomic Size ◽  
Wide Range ◽  
A Chain

It is interesting to observe polymers at atomic size resolution. Some works have been reported for thorium pyromellitate by using a STEM (1), or a CTEM (2,3). The results showed that this polymer forms a chain in which thorium atoms are arranged. However, the distance between adjacent thorium atoms varies over a wide range (0.4-1.3nm) according to the different authors.The present authors have also observed thorium pyromellitate specimens by means of a field emission STEM, described in reference 4. The specimen was prepared by placing a drop of thorium pyromellitate in 10-3 CH3OH solution onto an amorphous carbon film about 2nm thick. The dark field image is shown in Fig. 1A. Thorium atoms are clearly observed as regular atom rows having a spacing of 0.85nm. This lattice gradually deteriorated by successive observations. The image changed to granular structures, as shown in Fig. 1B, which was taken after four scanning frames.

Development of a conical anode Fe-gun for low voltage SEM

1988 ◽  
Vol 46 ◽  
pp. 978-979
Author(s):  
T. Miyokawa ◽  
S. Norioka ◽  
S. Goto
Keyword(s):  
High Resolution ◽  
Field Emission ◽  
Low Voltage ◽  
Irradiation Damage ◽  
Cold Cathode ◽  
Virtual Source ◽  
Source Position ◽  
Electrostatic Lens ◽  
Electrostatic Lenses ◽  
Wide Range

Field emission SEMs (FE-SEMs) are becoming popular due to their high resolution needs. In the field of semiconductor product, it is demanded to use the low accelerating voltage FE-SEM to avoid the electron irradiation damage and the electron charging up on samples. However the accelerating voltage of usual SEM with FE-gun is limited until 1 kV, which is not enough small for the present demands, because the virtual source goes far from the tip in lower accelerating voltages. This virtual source position depends on the shape of the electrostatic lens. So, we investigated several types of electrostatic lenses to be applicable to the lower accelerating voltage. In the result, it is found a field emission gun with a conical anode is effectively applied for a wide range of low accelerating voltages.A field emission gun usually consists of a field emission tip (cold cathode) and the Butler type electrostatic lens.

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