Synthesis Of Architectures Research Articles

Polymer infiltration synthesis of inorganic nanoporous coatings: Does polymer template affect their properties?

Synthesis of all-inorganic metal oxide architectures using polymer templates offers control over their thickness, porosity, and composition. Here, we provide insights into the synthesis of nanoporous zinc oxide films as a model system via infiltration of polymers that have different mechanisms of interaction with metal oxide precursors such as a polymer of intrinsic microporosity (PIM-1) and representative of the block-copolymers family (polystyrene-polyvinyl pyridine block copolymer). We investigated polymer infiltration process with both gas (diethyl zinc, DEZ, and water vapors) and solution (zinc acetylacetonate, Zn(acac)2, dissolved in ethanol) phase precursors. Using quartz crystal microbalance (QCM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses, we systematically studied the effect of polymer template and the form of the metal oxide precursors on the properties of synthesized metal oxide thin coatings. We demonstrate that the infiltration of polymer templates can be efficiently achieved using both gas phase and solution phase precursors. We show that the crystallinity of the synthesized 200 nm ZnO films is mainly affected by the state of the precursor (gas or solution phase) and does not depend on the polymer template type. In turn, the polymer type affects the surface termination of ZnO films. We demonstrate that the surface of porous ZnO coatings synthesized with BCP (here PS-P4VP) is more accessible than the surface of ZnO synthesized with PIM; however, despite the lower surface accessibility for ethanol molecules, ZnO synthesized via infiltration of PIM-1 with solution-phase precursors demonstrates the largest change in resistivity upon its exposure to ethanol vapor at room temperature.

Works of Art in the Turkish Grain Board (TMO) General Directorate Building

Turkish Grain Board (TMO) General Directorate Building was designed by Vedat Özsan, Cengiz Bektaş and Oral Vural (Özsan-Bektaş-Vural Architects) in 1964 and constructed between 1964 and 1968 in Ankara. One of the significant aspects of the building is the involvement of works of art. One percent of the building cost was allocated to the works of art. Moreover, the architects get inspired by some artists during the building design. Such kind of art and architecture synthesis was common in modern architecture between 1950 and 1980 both in Turkey and in the world. However, this aspect of the TMO building is not known enough in the literature. The aim of this study is to analyze the works of art in TMO General Directorate building in terms of art and architecture synthesis. The research method was mainly based on the analysis of the building on site and the evaluations of existing artworks with the literature about art and architecture synthesis, individual writings of architect Cengiz Bektaş and some artists (Bedri Rahmi Eyüboğlu, Burhan Alkar etc.). These works of art vary from wall ceramic to stained glass, and after 1988, a monumental sculpture was added to the building via competition. Moreover, after this sculptor competition, TMO established a plastic arts application center in 1989.

Synthesis of porous Mn2O3 architecture for supercapacitor electrode application

Transition metal oxides (TMOs) are a potential candidate for supercapacitor due to its outstanding characteristics such as cheap, abundant and non-toxic. But poor electron conductivity and large volume expansion at charge/discharge process limit their practical application as electrode materials. It is a feasible strategy to design porous TMOs which could provide high surface area and more electroactive sites to improve electrochemical performance. Herein, a porous Mn2O3 was synthesized by hard-template method using MCM-41 as template. It exhibits superior pore property of high specific surface area of 382 m2 g−1. And applied it as electrode material for supercapacitor, the porous Mn2O3 shows higher specific capacitance of 102 F g−1 compared to 4.88 F g−1 and 2.28 F g−1 of two types of block Mn2O3 with surface area 7.27 m2 g−1 and 2.67 m2 g−1 at discharging current density of 0.2 A g−1. Furthermore, it exhibits excellent long cycle stability in that specific capacitance remains stable after 5000 cycles (137% of the initial value). This research demonstrates that the porous Mn2O3 has broad potential as promising electrode materials for supercapacitors.

SYNTHESIS AND FPGA VALIDATION OF PARALLEL PREFIX ADDERS

In this work, the design implementation, functionality testing, design synthesis and bitstream generation of various n-bit adder architecture of RCA, CLA, CSkA and KSA. And addresses various forms of adders which include Ripple-carry (RCA), Carry-lookahead (CLA), Carry-skip (CSkA), and Kogge-stone (KSA) adders. Certain design restrictions for digital VLSI circuits, such speed and area, can be satisfied using these adders. All the mentioned adder are designed using Verilog HDL, implemented the same on Xilinx Vivado 2018.2, functionality test is carried out by writing testbench, bitstream generated for the same and synthesized using Cadence genus.

Analysis and Synthesis of Architectures for Automotive Battery Management Systems

Current batteries of battery electric vehicles (BEVs) require a battery management system (BMS) in order to enable a safe and long-lasting operation. The main functions of the battery management systems are a continuous monitoring of the voltage of each cell, a continuous monitoring of the battery temperature, the control of the charge current and the discharge current as well as the prevention of both a deep discharge and an overcharging. For the realization of these functions, different architectures are possible, ranging from an individual intelligent system at each cell up to a realization of the whole BMS within one central computing unit for the whole vehicle. This paper investigates and structures different architectural possibilities, discusses analysis possibilities and presents approaches for the synthesis of sensible architectures such as BMS. A concept synthesis for the start-up and shut-down of the high-voltage system is presented by comparing three different integrated pre- and discharging circuits and using a Hardware-in-the-Loop (HiL) program as an example. Finally, a topology consisting of three switches and two resistors (3S2R2) turns out to be the best one, due to the number of components, safety and price.

Design of Photoredox-Catalyzed Giese-Type Reaction for the Synthesis of Chiral Quaternary α-Aryl Amino Acid Derivatives via Clayden Rearrangement.

Chiral quaternary α-aryl amino acids are biologically valued but synthetically challenging building blocks. Herein, we report a strategy for the synthesis of molecular architectures by unifying a photoredox catalytic asymmetric Giese-type reaction and Clayden rearrangement. A new class of chiral Karady-Beckwith dehydroalanines is designed and serves as a versatile handle for the photoredox-mediated highly stereoselective Giese-type reaction with feedstock carboxylic acids and tertiary amines. Subsequent Clayden rearrangement delivers chiral quaternary α-aryl amino acid derivatives with high stereoselectivity. The versatile approach offers a reliable source for the assembly of highly demanding chiral building blocks.

Enantioselective Synthesis of [5]Helicenes Containing Two Additional Chiral Axes

AbstractA Au‐catalyzed protocol for the enantioselective synthesis of molecular architectures containing an internal [5]helicene and two peripherical axial stereogenic elements is described. While the diasteroselectivity of the double alkyne hydroarylation sequence is not optimal, and mixtures that contain similar amounts of two of the four possible diasteromeric products are obtained (one C2 and one non‐symmetric), the assembly of the C2‐symmetric isomer often occurs with high enantioselectivity (up to 98 % ee). The absolute configurations of the products obtained were determined by X‐ray crystallography. Studies on the thermal racemization of the internal [5]helicene moiety in the C2‐symmetric isomers determined the half‐life of this element to be approximately 3 h at 50 °C.

Ni-catalyzed carbamoylation of unactivated alkenes for stereoselective construction of six-membered lactams

Nitrogen-based heterocycles have aroused widespread interest due to their reoccurrence in many pharmaceuticals. Amongst these motifs, the enantioenriched lactams are the ubiquitous scaffolds found in myriad biologically active natural products and drugs. Recently, the transition metal-catalyzed asymmetric carbamoylation has been widely employed as a straightforward arsenal for chiral lactam architecture synthesis, including β-lactam and γ-lactam. However, despite the extensive efforts, there still remains no protocol to accomplish the related δ-lactam synthesis. In this manuscript, the Ni-catalyzed enantioselective carbamoylation of unactivated alkenes by the leverage of reductive dicarbofunctionalization strategy allows for the expedient access to two types of mostly common six-membered lactams: 3,4-dihydroquinolinones and 2-piperidinone in high yield and enantioselectivity. This protocol features with good functional group tolerance, as well as broad substrate scope. The newly developed chiral 8-Quinox skeleton ligand is the key parameter for this transformation, which significantly enhances the reactivity and enantioselectivity.

(Invited) Self-Assembly Synthesis and Interfacial Control of Electrode Architectures

Enhancement in electrochemical energy storage resides in tailored nanotextures resulting from making electrode materials with controlled compositions and structures. The complex interplay of solvent and solute structures and dynamics at charged interfaces, the transport of electrolyte ions into and out of pores, solvation/desolvation processes occurring in pores approaching bare-ion dimensions, and formation of interfaces via chemical reactions are all important parameters. Herein, several self-assembly synthesis methods for carbon and oxide composites as electrode materials for energy storage will be discussed. The objective of this talk is to demonstrate that nanostructured carbons and oxides derived from soft-template synthesis not only entail a high storage capacity but also, most importantly, can be made to have a significantly enhanced electronic & ionic conductivities and storage capacities. These enhanced transport properties in electrode architectures are the key to providing a high-rate capability for the corresponding energy storage systems.

Synthesis of 7,2'-Dihydroxy-4',5'-Dimethoxyisoflavanone, a Phytoestrogen with Derma Papilla Cell Proliferative Activity.

This paper reports a concise and scalable method for the synthesis of the phytoestrogen 7,2′-dihydroxy-4′,5′-dimethoxyisoflavanone 1 via an optimized synthetic route. Compound 1 was readily obtained in 11 steps and 11% overall yield on a gram scale from commercially available 3,4-dimethoxyphenol. The key features of the synthesis include the construction of the deoxybenzoin unit through a sequence of Claisen rearrangement, oxidative cleavage, and aryllithium addition and the efficient synthesis of the isoflavanone architecture from highly functionalized 2-hydroxyketone.

Tetracyanobutadiene Bridged Push-Pull Chromophores: Development of New Generation Optoelectronic Materials.

This review describes the design strategies used for the synthesis of various tetracyanobutadiene bridged donor-acceptor molecular architectures by a click type [2+2] cycloaddition-retroelectrocyclization (CA-RE) reaction sequence. The photophysical and electrochemical properties of the tetracyanobutadiene bridged molecular architectures based on various moieties including diketopyrrolopyrrole, isoindigo, benzothiadiazole, pyrene, pyrazabole, truxene, boron dipyrromethene (BODIPY), phenothiazine, triphenylamine, thiazole and bisthiazole are summarized. Further, we discuss some important applications of the tetracyanobutadiene bridged derivatives in dye sensitized solar cells, bulk heterojunction solar cells and photothermal cancer therapy.

Facile synthesis of discus-like porous CuO architectures and their enhanced xylene gas sensing performances

• Discus-like porous CuO architectures are fabricated by a facile route. • Discus-like porous CuO can rapidly detect xylene with superior stability. • Porous structure and catalytic oxidation of CuO improve sensing behaviors. The discus-like porous CuO architectures have been successfully synthesized through a facile room temperature coprecipitation approach followed by subsequent annealing treatment. The multiple characterizations by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) demonstrate that the as-prepared CuO samples show unique discus-like porous structures with superior morphological homogeneity and dispersion. When applied as a gas sensing material, discus-like porous CuO based gas sensor shows an enhanced xylene gas sensing performance, including a fast response/recovery speed (2 s/13 s) and well stability as well as repeatability at an optimal working temperature of 260 ℃. The superior xylene gas sensing properties are predominantly attributed to the synergistic effect of porous discus-like architectures and the catalytic oxidation of p-type semiconductor CuO on xylene gas.

АНАЛИЗ ФУНКЦИОНИРОВАНИЯ ПОДСИСТЕМЫ КОНТРОЛЯ УТЕЧЕК ИНФОРМАЦИИ АВТОМАТИЗИРОВАННОЙ СИСТЕМЫ В ЗАЩИЩЕННОМ ИСПОЛНЕНИИ

The aim of the study is to increase the efficiency of the information leak control sub-system of a protected automated system based on the rational redistribution of resources.
 The article is devoted to solving a specific scientific problem to analyse the information leak control subsystem of a protected automated system.
 The research method is analysing the architectures of the information leak prevention system and the information security monitoring centre, highlighting the architecture short-comings. Subsequently, the architecture synthesis of the information leak prevention system and the information security monitoring centre is presented; also the formal statement of the problem is described. 
 The novelty of this study lies in developing a model and methodology for evaluating the efficiency of the information leak control subsystem of a protected automated system.
 As an analysis result of operating the information leak control subsystem of a protected automated system, a number of short-comings are identified and a method for solving them is presented. 
 Thus, to solve the problem, parameters are introduced and determining their optimality minimises information leakage of a protected automated system

Supramolecular Catalysts for Organic Synthesis: Preparation and Applications of Cyclodextrins and Calixarenes in C−C Cross‐Coupling Reactions

AbstractReactions that promote the formation of carbon–carbon bonds are of great importance in organic synthesis, since they transform available, relatively inexpensive, and small organic molecules into more complex ones. One of the main protocols used for these transformations are cross‐coupling reactions, and due to their versatility and applications, several efforts have been devoted recently to developing catalysts for such reactions. Supramolecular chemistry has become a major player in this field and encompasses approaches that range from the synthesis of intricate complex architectures that may mimic enzymes, the slight structural modification of commercially available scaffolds, or even repurposing highly available materials such as agarose. This Review discusses the development of supramolecular catalysts for cross‐coupling reactions, focusing mostly on the Suzuki, Heck and Sonogashira reactions promoted by such assemblies.

RAFT Step-Growth Polymerization of Diacrylates.

RAFT step-growth polymerization was previously demonstrated with monomers that bear low rate of homopropagation to favor the chain transfer process; by contrast, acrylates are known to be fast homopropagating monomers, thereby posing serious challenges for RAFT step-growth. Here, we identified a chain transfer agent (CTA) that rapidly yields single unit monomer inserted (SUMI) CTA adducts with a model acrylate monomer. Using a bifunctional reagent of this CTA, we successfully demonstrated RAFT step-growth polymerization with diacrylates, yielding linear polymer backbones. Furthermore, we achieved inclusion of functionality (i.e., disulfide) into RAFT step-growth polymer via a disulfide incorporated bifunctional CTA. Grafting from this backbone resulted in molecular brush polymers with cleavable functionality in each repeat unit of the backbone, allowing selective degradation to afford well-defined unimolecular species of two polymeric side chains. Given the wide selection of commercially available diacrylates, RAFT step-growth polymerization of diacrylates will further enable facile synthesis of complex architectures with modular backbones.

Synthesis of Mo-doped NiFe-phosphate hollow bird-nest architecture for efficient and stable seawater electrolysis

Seawater electrolysis achieves sustainable hydrogen production and seawater desalination in the context of the scarcity of freshwater resources, achieving two birds with one stone. In this study, we reported an Mo-doped NiFe-phosphate hollow bird-nest architecture consisting of porous nanosheets on NiFe-foam (Mo-NiFe-PO3/NFF) as an admired bifunctional electrocatalyst for overall seawater splitting. The introduction of Mo distorted the crystal structure of NiFe-phosphate, regulated the electronic environment around the Ni/Fe, and improved the electrocatalytic activity. Moreover, it also cooperated with phosphate polyanions to resist the Cl− from seawater and enhanced the corrosion resistance. The Mo-NiFe-PO3/NFF exhibited outstanding electrocatalytic performance for alkaline seawater electrolysis under a two-electrode system where only required 1.65 V voltage to drive 100 mA cm−2. Particularly, the electrolyzer afforded industrially current density up to 500 mA cm−2 at a low voltage of 1.78 V, which were responsible for excellent durability up to 100 h. The bifunctional electrocatalyst in this study not only possessed high catalytic activity, but also effectively resisted the corrosion of Cl− in seawater.

Seed-induced synthesis of hierarchical architectures of ZSM-5 nanocrystalline aggregates by the solid state crystallization

A seed-induced rapid synthesis of hierarchical ZSM-5 aggregates was achieved by the solid state conversion method in an inorganic system. No secondary mesoporogen was introduced to construct supplementary pore. The physical and chemical properties of the products were characterized by using XRD, SEM, TEM, XRF and N2 adsorption–desorption techniques. The results revealed that the synthesized samples typically exhibit the uniform spherical zeolite ZSM-5 aggregates composed of loosely packed nanocrystals. It was clearly found that the morphology, mesoporosity and particle size of synthesized samples were directly affected by the type of the seed and synthesis conditions. The well-dispersed hierarchical ZSM-5 aggregates were synthesized at NaOH/SiO2 = 0.15, 20 ≤ SiO2/Al2O3 ≤ 40 with the acid of zeolite seed solution in guiding the structure. In addition, the crystal growth of zeolite samples synthesized with zeolite seed solution was studied at 433, 453, and 473 K. The results suggested that the activation energies for the induction, transition and crystallization stages were 91.44, 104.37 and 77.68 kJ∙mol−1, respectively. The method provides a cost-effective and industrially applicable route to synthesize hierarchical ZSM-5 aggregates.

IPP/PE Multiblock Copolymers for Plastic Blend Recycling Synthesized by Coordinative Chain Transfer Polymerization

Recycling of blends of widely used plastics is a key challenge of the envisioned circular economy, and thus, protocols permitting the efficient synthesis of effective compatibilizers are highly desirable. We report herein that coordinative chain transfer polymerization permits the efficient one-pot synthesis of multiblock architectures of strictly linear polyethylene or high-density polyethylene (HDPE) and isotactic polypropylene (iPP). Various block copolymers having an iPP backbone and HDPE side chains were synthesized and used to compatibilize HDPE/iPP plastic blends. The synthesized block copolymers differ in their overall molecular weights and have different HDPE side chain lengths and numbers. A block copolymer with a molecular weight of Mp = 33,700 g × mol–1 including 4.5 HDPE side chains with a molecular weight of Mn = 600 g × mol–1 showed the highest efficiency for compatibilizing 30/70 wt % blends of HDPE/iPP with a 5 wt % compatibilizer addition. This block copolymer is also superior to commercially available compatibilizers.

Corroles As Precursors of Porous Organic Polymers (POPs) and Molecularly Imprinted Polymers (MIPs) - Application to the Detection of CO and the Decontamination of Chemical Nerve Agents

Detection of carbon monoxide (CO) at few ppm levels is a critical point for quality control of domestic and industrial environment. CO is responsible for thousands of intoxications and hundreds of deaths per year in the world. Moreover, CO is a residual gas found in the industrial dihydrogen used for Proton Exchange Membrane fuel cell, and deactivates the fuel cell prematurely. Corroles have been largely used in sensing applications.[1] Cobalt corroles display high binding affinity for carbon monoxide even in the presence of nitrogen and dioxygen.[2] The affinity of the Co(III) metallocorroles for CO is directly correlated with the Lewis acid character of the metal center. The electrochemistry and spectro-electrochemistry properties have been studied. We have shown that structural modifications on the aromatic ring have a direct influence on the reactivity of the metal complex. We have recently obtained very low CO detection level (ppm) using SAW devices functionalized by cobalt corrole deposited as a film on a silica or a gold surface.[3] Our previous work on the synthesis of porous sol-gel materials functionalized by cobalt corroles gave us encouraging results for CO sorption and detection and prompted us to prepare new porous structured materials functionalized by corrole complexes for gas detection applications. Among all the methods of synthesis of porous architectures, organic materials belonging to the POP (Porous Organic Polymer) family are an appealing and original approach in this research field.[4] The synthesis of new POPs functionalized by cobalt corroles (Fig. 1) will be reported. Their selective sorption properties for CO over N2, O2 and CO2 will be also presented.Preliminary results concerning the design of Molecularly Imprinted Polymers (MIPS) as enzyme mimics for the decontamination of a broad spectrum of pesticides and chemical warfare agents will be also reported.Authors would like to acknowledge the ANR program (MIPEnz-Decontam, 20-CE39-0016-01), the FEDER and the “Région Bourgogne” for financial support (ISITE CO2DECIN) REFERENCES: [1] Di Natale, C.; Gros, C. P.; Paolesse, R., Chem. Soc. Rev. 2022, 000;[2] J.-M. Barbe, G. Canard, S. Brandès, F. Jerôme, G. Dubois, R. Guilard, Dalton Trans. 2004, 1208-1214; [3] Vanotti, M.; Poisson, S.; Soumann, V.; Quesneau, V.; Brandes, S.; Desbois, N.; Yang, J.; Andre, L.; Gros, C. P.; Blondeau-Patissier, V., Sensors and Actuators B: Chemical 2021, (332), 129507. [4] S. Brandès, V. Quesneau, O. Fonquernie, N. Desbois, V. Blondeau-Patissier, C. P. Gros, Dalton Trans. 2019, 48, 11651-11662 (Front Cover). Figure 1

Linear and Star Block Copolymer Nanoparticles Prepared by Heterogeneous RAFT Polymerization Using an ω,ω-Heterodifunctional Macro-RAFT Agent.

Herein, an ω,ω-heterodifunctional macromolecular reversible addition-fragmentation chain transfer (macro-RAFT) agent containing two different RAFT end groups was synthesized and employed to mediate aqueous photoinitiated RAFT dispersion polymerization of a methacrylic monomer. Because of the different RAFT controllability of two RAFT end groups toward methacrylic monomers, the RAFT end group with good controllability dominated the polymerization while the other RAFT end group with poor controllability was unreacted, leading to the formation of linear block copolymers. Because of the unique structure of the linear block copolymers, a diverse set of block copolymer nanoparticles with rich RAFT groups at the interface of the hydrophilic corona/the hydrophobic core were successfully prepared. Finally, μ-A(BC)C miktoarm star block copolymer nanoparticles were prepared by RAFT seeded emulsion polymerization of an acrylic monomer, which enables the further morphological control over polymer nanoparticles. We believe that the utilization of an ω,ω-heterodifunctional macro-RAFT agent in heterogeneous RAFT polymerization will offer considerable opportunities for the rational synthesis of well-defined molecular architectures and polymer nanoparticles.