Fe@B6H6 Aggregates: From Simple Building Blocks to Graphene Analogue

2021 ◽  
Author(s):  
Chao Wang ◽  
Jianhua Hou ◽  
Qian Duan
Keyword(s):  
Building Block ◽  
Building Blocks ◽  
Electron Structure ◽  
Chemical Doping ◽  
Hole Density ◽  
Hexagonal Hole

Abstract We suggest the possibility to build graphene analogue with the planar hexacoordinate wheel-type Fe@B6H6 cluster as the building block through studying theoretically the geometry, stability and electron structure of its dimer and trimer as well as the dimerization of the two trimers. Employing the dehydrogenation route to polymerization, we can obtain the hexagonal boron sheet that are partly and uniformly filled by Fe atoms in the center of the holes, achieving uniform chemical doping and a very large hexagonal-hole-density. Thus, we may offer a novel cluster-assembled material for experimental chemists to construct graphene analogue.

Thienopyrrolocarbazoles: New Building Blocks for Functional Organic Materials

2019 ◽  
Author(s):  
Dorian Bader ◽  
Johannes Fröhlich ◽  
Paul Kautny
Keyword(s):  
Building Block ◽  
Organic Materials ◽  
Building Blocks ◽  
Molecular Properties ◽  
The Family ◽  
Facile Preparation

The facile preparation of three regioisomeric thienopyrrolocarbazoles applying a convenient C-H activation approach is presented. Derived from indolo[3,2,1-<i>jk</i>]carbazole, the incorporation of thiophene into the triarylamine framework significantly impacted the molecular properties of the parent scaffold. The developed thienopyrrolocarbazoles enrich the family of triarylamine donors and constitute a novel building block for functional organic materials.

Thienopyrrolocarbazoles: New Building Blocks for Functional Organic Materials

2019 ◽  
Author(s):  
Dorian Bader ◽  
Johannes Fröhlich ◽  
Paul Kautny
Keyword(s):  
Building Block ◽  
Organic Materials ◽  
Building Blocks ◽  
Molecular Properties ◽  
The Family ◽  
Facile Preparation

The facile preparation of three regioisomeric thienopyrrolocarbazoles applying a convenient C-H activation approach is presented. Derived from indolo[3,2,1-<i>jk</i>]carbazole, the incorporation of thiophene into the triarylamine framework significantly impacted the molecular properties of the parent scaffold. The developed thienopyrrolocarbazoles enrich the family of triarylamine donors and constitute a novel building block for functional organic materials.

scholarly journals PyroMEMS as Future Technological Building Blocks for Advanced Microenergetic Systems

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 118
Author(s):  
Jean-Laurent Pouchairet ◽  
Carole Rossi
Keyword(s):  
Building Block ◽  
Building Blocks ◽  
Small Scale ◽  
Technological Evolution ◽  
Research Groups ◽  
Function Block ◽  
The Past ◽  
New Methods ◽  
Safety And Reliability ◽  
Electronically Controllable

For the past two decades, many research groups have investigated new methods for reducing the size and cost of safe and arm-fire systems, while also improving their safety and reliability, through batch processing. Simultaneously, micro- and nanotechnology advancements regarding nanothermite materials have enabled the production of a key technological building block: pyrotechnical microsystems (pyroMEMS). This building block simply consists of microscale electric initiators with a thin thermite layer as the ignition charge. This microscale to millimeter-scale addressable pyroMEMS enables the integration of intelligence into centimeter-scale pyrotechnical systems. To illustrate this technological evolution, we hereby present the development of a smart infrared (IR) electronically controllable flare consisting of three distinct components: (1) a controllable pyrotechnical ejection block comprising three independently addressable small-scale propellers, all integrated into a one-piece molded and interconnected device, (2) a terminal function block comprising a structured IR pyrotechnical loaf coupled with a microinitiation stage integrating low-energy addressable pyroMEMS, and (3) a connected, autonomous, STANAG 4187 compliant, electronic sensor arming and firing block.

scholarly journals Lipase Catalyzed Synthesis of Enantiopure Precursors and Derivatives for β-Blockers Practolol, Pindolol and Carteolol

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 503
Author(s):  
Morten Gundersen ◽  
Guro Austli ◽  
Sigrid Løvland ◽  
Mari Hansen ◽  
Mari Rødseth ◽  
...  
Keyword(s):  
Building Block ◽  
Kinetic Resolution ◽  
Enantiomeric Excess ◽  
Catalytic Amount ◽  
Building Blocks ◽  
Β Blocker ◽  
Β Blockers ◽  
Optical Rotations ◽  
Reported Data ◽  
By Products

Sustainable methods for producing enantiopure drugs have been developed. Chlorohydrins as building blocks for several β-blockers have been synthesized in high enantiomeric purity by chemo-enzymatic methods. The yield of the chlorohydrins increased by the use of catalytic amount of base. The reason for this was found to be the reduced formation of the dimeric by-products compared to the use of higher concentration of the base. An overall reduction of reagents and reaction time was also obtained compared to our previously reported data of similar compounds. The enantiomers of the chlorohydrin building blocks were obtained by kinetic resolution of the racemate in transesterification reactions catalyzed by Candida antarctica Lipase B (CALB). Optical rotations confirmed the absolute configuration of the enantiopure drugs. The β-blocker (S)-practolol ((S)-N-(4-(2-hydroxy-3-(isopropylamino)propoxy)phenyl)acetamide) was synthesized with 96% enantiomeric excess (ee) from the chlorohydrin (R)-N-(4-(3-chloro-2 hydroxypropoxy)phenyl)acetamide, which was produced in 97% ee and with 27% yield. Racemic building block 1-((1H-indol-4-yl)oxy)-3-chloropropan-2-ol for the β-blocker pindolol was produced in 53% yield and (R)-1-((1H-indol-4-yl)oxy)-3-chloropropan-2-ol was produced in 92% ee. The chlorohydrin 7-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one, a building block for a derivative of carteolol was produced in 77% yield. (R)-7-(3-Chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one was obtained in 96% ee. The S-enantiomer of this carteolol derivative was produced in 97% ee in 87% yield. Racemic building block 5-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one, building block for the drug carteolol, was also produced in 53% yield, with 96% ee of the R-chlorohydrin (R)-5-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one. (S)-Carteolol was produced in 96% ee with low yield, which easily can be improved.

scholarly journals Dimerization and oligomerization of DNA-assembled building blocks for controlled multi-motion in high-order architectures

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ling Xin ◽  
Xiaoyang Duan ◽  
Na Liu
Keyword(s):  
Building Block ◽  
Degrees Of Freedom ◽  
Building Blocks ◽  
Single Type ◽  
Hierarchical Assembly ◽  
Optical Responses ◽  
Self Association ◽  
Living Organisms ◽  
Order Structures ◽  
Chiral System

AbstractIn living organisms, proteins are organized prevalently through a self-association mechanism to form dimers and oligomers, which often confer new functions at the intermolecular interfaces. Despite the progress on DNA-assembled artificial systems, endeavors have been largely paid to achieve monomeric nanostructures that mimic motor proteins for a single type of motion. Here, we demonstrate a DNA-assembled building block with rotary and walking modules, which can introduce new motion through dimerization and oligomerization. The building block is a chiral system, comprising two interacting gold nanorods to perform rotation and walking, respectively. Through dimerization, two building blocks can form a dimer to yield coordinated sliding. Further oligomerization leads to higher-order structures, containing alternating rotation and sliding dimer interfaces to impose structural twisting. Our hierarchical assembly scheme offers a design blueprint to construct DNA-assembled advanced architectures with high degrees of freedom to tailor the optical responses and regulate multi-motion on the nanoscale.

scholarly journals Bioelectrocatalytic hydrogels from electron-conducting metallopolypeptides coassembled with bifunctional enzymatic building blocks

2008 ◽  
Vol 105 (40) ◽  
pp. 15275-15280 ◽  
Author(s):  
Ian R. Wheeldon ◽  
Joshua W. Gallaway ◽  
Scott Calabrese Barton ◽  
Scott Banta
Keyword(s):  
Polyphenol Oxidase ◽  
Building Block ◽  
Leucine Zipper ◽  
Electrical Contact ◽  
Building Blocks ◽  
Coiled Coils ◽  
Biofuel Cell ◽  
Random Coil ◽  
Catalytic Current ◽  
And Function

Here, we present two bifunctional protein building blocks that coassemble to form a bioelectrocatalytic hydrogel that catalyzes the reduction of dioxygen to water. One building block, a metallopolypeptide based on a previously designed triblock polypeptide, is electron-conducting. A second building block is a chimera of artificial α-helical leucine zipper and random coil domains fused to a polyphenol oxidase, small laccase (SLAC). The metallopolypeptide has a helix–random-helix secondary structure and forms a hydrogel via tetrameric coiled coils. The helical and random domains are identical to those fused to the polyphenol oxidase. Electron-conducting functionality is derived from the divalent attachment of an osmium bis-bipyrdine complex to histidine residues within the peptide. Attachment of the osmium moiety is demonstrated by mass spectroscopy (MS-MALDI-TOF) and cyclic voltammetry. The structure and function of the α-helical domains are confirmed by circular dichroism spectroscopy and by rheological measurements. The metallopolypeptide shows the ability to make electrical contact to a solid-state electrode and to the redox centers of modified SLAC. Neat samples of the modified SLAC form hydrogels, indicating that the fused α-helical domain functions as a physical cross-linker. The fusion does not disrupt dimer formation, a necessity for catalytic activity. Mixtures of the two building blocks coassemble to form a continuous supramolecular hydrogel that, when polarized, generates a catalytic current in the presence of oxygen. The specific application of the system is a biofuel cell cathode, but this protein-engineering approach to advanced functional hydrogel design is general and broadly applicable to biocatalytic, biosensing, and tissue-engineering applications.

scholarly journals Composition, Separation of Roles and Model-Driven Approaches as Enabler of a Robotics Software Ecosystem

2020 ◽  
pp. 53-108
Author(s):  
Christian Schlegel ◽  
Alex Lotz ◽  
Matthias Lutz ◽  
Dennis Stampfer
Keyword(s):  
Complex Systems ◽  
Open Source ◽  
Building Block ◽  
Building Blocks ◽  
Software Systems ◽  
Software Components ◽  
Separation Of Concerns ◽  
Software Ecosystem ◽  
Model Driven ◽  
Successful Approach

AbstractSuccessful engineering principles for building software systems rely on the separation of concerns for mastering complexity. However, just working on different concerns of a system in a collaborative way is not good enough for economically feasible tailored solutions. A successful approach for this is the composition of complex systems out of commodity building blocks. These come as is and can be represented as blocks with ports via data sheets. Data sheets are models and allow a proper selection and configuration as well as the prediction of the behavior of a building block in a specific context. This chapter explains how model-driven approaches can be used to support separation of roles and composition for robotics software systems. The models, open-source tools, open-source robotics software components and fully deployable robotics software systems shape a robotics software ecosystem.

scholarly journals Who is the ultimate master of contractual, regulatory, discretionary and residual cash flows? An answer from the standpoint of corporate governance

2008 ◽  
Vol 6 (1-4) ◽  
pp. 424-432 ◽  
Author(s):  
Rodolfo Apreda
Keyword(s):  
Corporate Governance ◽  
Cash Flow ◽  
Building Block ◽  
Flow Model ◽  
Building Blocks ◽  
Cash Flows ◽  
Senior Management ◽  
Investment Portfolio ◽  
Decision Rights ◽  
Rules Of The Game

This paper sets forth a framework of analysis that links contractual, discretionary, regulatory and residual cash flows with decision rights over them. To attain this purpose, firstly we introduce the standard incremental cash flow model, underlying its main limitations. Secondly, we move on bringing to light cash flows to senior management and directors, as well as the so-often neglected investment portfolio. Next, we settle down to what we are going to call the compact cash flow model that comprises five building blocks, namely those arising out of assets, those addressed to owners, creditors, managers and directors, and lastly the company’s investment portfolio. Afterwards, contractual, discretionary, regulatory and residual cash flows are enlarged upon. Last of all, we focus on decision rights over every constituent of each building block. This issue carries weight in Corporate Governance since stakeholders who claim or exercise decision rights, also could trespass on the rules of the game, becoming better off to the expense and damage of other stakeholders.

A Building Block Approach to Monofluorinated Organic Compounds

2008 ◽  
Vol 73 (12) ◽  
pp. 1553-1611 ◽  
Author(s):  
Alexander S. Konev ◽  
Alexander F. Khlebnikov
Keyword(s):  
Organic Compounds ◽  
Building Block ◽  
Building Blocks ◽  
Natural Compounds ◽  
Pericyclic Reactions ◽  
Fluoroacetic Acid ◽  
Phosphorus Containing ◽  
Block Approach

Building blocks for the synthesis of monofluorinated organic compounds are reviewed. The synthetic potential of polyhalomethanes, sulfur- and phosphorus-containing building blocks, difluoroethene, polyhaloethanes, fluoroacetic acid derivatives, and other compounds are described. Pericyclic reactions involving fluorinated compounds and application of the methodology of building blocks to the synthesis of monofluorinated pharmaceuticals and analogs of natural compounds are considered. The review with 317 references covers mainly the literature from 1996 through 2007.

Achieving high carrier density and high mobility in graphene using monolayer tungsten oxyselenide

2021 ◽  
Author(s):  
Min Sup Choi ◽  
Ankur Nipane ◽  
Brian Kim ◽  
Mark Ziffer ◽  
Ipshita Datta ◽  
...  
Keyword(s):  
Carrier Density ◽  
Phonon Scattering ◽  
High Mobility ◽  
Transparent Conductors ◽  
Ring Resonators ◽  
Chemical Doping ◽  
Electrostatic Model ◽  
Hole Density ◽  
Phase Modulators ◽  
Doped Graphene

Abstract Highly doped graphene holds promise for next-generation electronic and photonic devices. However, chemical doping cannot be precisely controlled, and introduces external disorder that significantly diminishes the carrier mobility and therefore the graphene conductivity. Here, we show that monolayer tungsten oxyselenide (TOS) created by oxidation of WSe2 acts as an efficient and low-disorder hole-dopant for graphene. When the TOS is directly in contact with graphene, the induced hole density is 3 × 1013 cm-2 , and the room-temperature mobility is 2,000 cm2 /V·s, far exceeding that of chemically-doped graphene. Inserting WSe2 layers between the TOS and graphene tunes the induced hole density as well as reduces charge disorder such that the mobility exceeds 20,000 cm2 /V·s and reaches the limit set by acoustic phonon scattering, resulting in sheet resistance below 50 Ω/□. An electrostatic model based on work-function mismatch accurately describes the tuning of the carrier density with WSe2 interlayer thickness. These films show unparalleled performance as transparent conductors at telecommunication wavelengths, as shown by measurements of transmittance in thin films and insertion loss in photonic ring resonators. This work opens up new avenues in optoelectronics incorporating two-dimensional heterostructures including infrared transparent conductors, electro-phase modulators, and various junction devices.

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