Design Of Building Blocks Research Articles

Mechanical and Tribological Performances Enhanced by Self-Assembled Structures.

Taking inspiration from natural materials, composite materials can be reinforced by creating matrix architectures that can better accommodate and control internal stresses. Despite the recent success in the synthesis of artificial assemblies for local reinforcement through the introduction of oriented fibers and plates into host multilayered composites, there is a lack of fundamental understanding of the factors that determine mechanical properties. Moreover, designing building blocks and interfaces that facilitate higher resistance and energy dissipation is highly challenging. When the intrinsic material is fixed, the mechanical and tribological properties can be further adjusted. In this study, europium oxide nanosheets are arranged in interlocked-junction superstructures that resist sliding at junction points, thereby enhancing the mechanical properties of the nanosheet assemblies compared to those of the conventional face-to-face superstructures formed by parallel nanosheets. Furthermore, the crystalline origin of building blocks is revealed by demonstrating that faulty crystal nanosheets adopting an amorphous structure are different from single-crystal nanosheets, with the former exhibiting superior mechanical reinforcement and improved abrasive resistance.

SMELL SPACE

The human sense of smell is powerful. However, the way we use smell as an interaction modality in human–computer interaction (HCI) is limited. We lack a common reference point to guide designers’ choices when using smell. Here, we map out an olfactory design space to provide designers with such guidance. We identified four key design features: (i) chemical, (ii) emotional, (iii) spatial, and (iv) temporal. Each feature defines a building block for smell-based interaction design and is grounded in a review of the relevant scientific literature. We then demonstrate the design opportunities in three application cases. Each application (i.e., one desktop, two virtual reality implementations) highlights the design choices alongside the implementation and evaluation possibilities in using smell. We conclude by discussing how identifying those design features facilitates a healthy growth of this research domain and contributes to an intermediate-level knowledge space. Finally, we discuss further challenges the HCI community needs to tackle.

Dual-Functioning Antibacterial Eugenol-Derived Plasticizers for Polylactide.

Dual-functioning additives with plasticizing and antibacterial functions were designed by exploiting the natural aromatic compound eugenol and green platform chemical levulinic acid or valeric acid that can be produced from biobased resources. One-pot synthesis methodology was utilized to create three ester-rich plasticizers. The plasticizers were thoroughly characterized by several nuclear magnetic resonance techniques (1H NMR, 13C NMR, 31P NMR, HSQC, COSY, HMBC) and by electrospray ionization-mass spectrometry (ESI-MS) and their performances, as plasticizers for polylactide (PLA), were evaluated. The eugenyl valerate was equipped with a strong capability to depress the glass transition temperature (Tg) of PLA. Incorporating 30 wt% plasticizer led to a reduction of the Tg by 43 °C. This was also reflected by a remarkable change in mechanical properties, illustrated by a strain at break of 560%, almost 110 times the strain for the breaking of neat PLA. The two eugenyl levulinates also led to PLA with significantly increased strain at breaking. The eugenyl levulinates portrayed higher thermal stabilities than eugenyl valerate, both neat and in PLA blends. The different concentrations of phenol, carboxyl and alcohol functional groups in the three plasticizers caused different bactericidal activities. The eugenyl levulinate with the highest phenol-, carboxyl- and alcohol group content significantly inhibited the growth of Staphylococcus aureus and Escherichia coli, while the other two plasticizers could only inhibit the growth of Staphylococcus aureus. Thus, the utilization of eugenol as a building block in plasticizer design for PLA illustrated an interesting potential for production of additives with dual functions, being both plasticizers and antibacterial agents.

DPL-based novel CMOS 1-Trit Ternary Full-Adder

ABSTRACT This paper presents a new high-speed, low-power, area-efficient 1-trit Ternary-Full-Adder (TFA) as a building block for wave-pipelined ternary-digital system design. Balanced input capacitance with structural symmetry makes Double Pass-transistor Logic (DPL) an ideal candidate for this, and is employed here hence. Design-strategy with working-principle is presented. The TFA is designed and optimised on normal-process-enhancement-type MOS devices that use BSIM4 model-parameters, on 1.0 V supply-rail at 27°C temperature. Simulations are carried out using Tanner EDA V.16. The ternary values ‘0’, ‘1’ and ‘2’ are coded with 0 V, 0.5 V and 1.0 V, respectively. The circuit is time-equalised through coarse and fine-tuning for all data paths from input-to-output to offer efficient wave-pipelining feature. The transient response from T-Spice simulation is validated for all test-patterns. Physical design of proposed TFA is completed using TSMC 65 nm Single-Poly-Double-Metal (SPDM) CMOS process-technology using Microwind3.1. After DRC, LVS and parasitic extraction, the post-layout simulation is done. PVT analysis with statistical PVT (Process-Voltage-Temperature) variation is used to find a worst-case speed-power response of the TFA. Propagation delay is examined for all test patterns and is found satisfactory ensuring effective wave-pipelining. Comparative study with recent candidate designs reveals nearly 21.43% PDP-reduction over the best reported.

Electrochemical Scaled‐up Synthesis of Cyclic Enecarbamates as Starting Materials for Medicinal Chemistry Relevant Building Bocks

AbstractThe electrochemical Shono oxidation of Boc‐protected cyclic amines was revised. The conditions for scalable electrochemical synthesis of cyclic enecarbamates were found. The developed protocol included recycling of the full range of used reagents, favoring to E‐factor reduction according to Green Chemistry requirements. The method opened the way for the convenient preparation of previously uncommon materials, which could become useful synthetic intermediates. Their synthetic potential was evaluated in [2+1] and [2+2] cycloadditions as well as electrophilic functionalization. Moreover, functionalized enecarbamates with carbonyl groups in β‐position were used as latent 1,3‐bielectrophiles in classical heterocyclizations. In a case of the hydrazine, the corresponding unusually decorated pyrazoles were prepared. The proposed methodology is a straightforward tool for the design and synthesis of Medicinal Chemistry relevant building blocks. As examples, 5‐fluoro pipecolic and 3‐fluoro isonipecotic acids were synthesized starting from Boc‐protected esters of the pipecolic and the isonipecotic acids respectively; the 5‐step approach to pyrazole containing α‐aminoacids with different linkers between the aminoacidic and pyrazole moieties was elaborated based on the cheapest commercially available racemic and chiral cyclic α‐aminoacids; the convenient approach to the functionalized tetrahydropyrido[3,4‐d]pyridazines was proposed starting from Boc‐protected ester of the isonipecotic acids.magnified image

Electroactive Organic Building Blocks for the Chemical Design of Functional Porous Frameworks (MOFs and COFs) in Electronics.

Electroactive organic molecules have received a lot of attention in the field of electronics because of their fascinating electronic properties, easy functionalization and potential low cost towards their implementation in electronic devices. In recent years, electroactive organic molecules have also emerged as promising building blocks for the design and construction of crystalline porous frameworks such as metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs) for applications in electronics. Such porous materials present certain additional advantages such as, for example, an immense structural and functional versatility, combination of porosity with multiple electronic properties and the possibility of tuning their physical properties by post-synthetic modifications. In this Review, we summarize the main electroactive organic building blocks used in the past few years for the design and construction of functional porous materials (MOFs and COFs) for electronics with special emphasis on their electronic structure and function relationships. The different building blocks have been classified based on the electronic nature and main function of the resulting porous frameworks. The design and synthesis of novel electroactive organic molecules is encouraged towards the construction of functional porous frameworks exhibiting new functions and applications in electronics.

Identification and Analysis of Natural Building Blocks for Evolution-Guided Fragment-Based Protein Design

Natural evolution has generated an impressively diverse protein universe via duplication and recombination from a set of protein fragments that served as building blocks. The application of these concepts to the design of new proteins using subdomain-sized fragments from different folds has proven to be experimentally successful. To better understand how evolution has shaped our protein universe, we performed an all-against-all comparison of protein domains representing all naturally existing folds and identified conserved homologous protein fragments. Overall, we found more than 1000 protein fragments of various lengths among different folds through similarity network analysis. These fragments are present in very different protein environments and represent versatile building blocks for protein design. These data are available in our web server called F(old P)uzzle (fuzzle.uni-bayreuth.de), which allows to individually filter the dataset and create customized networks for folds of interest. We believe that our results serve as an invaluable resource for structural and evolutionary biologists and as raw material for the design of custom-made proteins.

Towards Active Self-Assembly Through DNA Nanotechnology.

Self-assembly, which is ubiquitous in living systems, also stimulates countless synthetic molecular self-assembling systems. Most synthetic self-assemblies are realized by passive processes, going from high-energy states to thermodynamic equilibrium. Conversely, living systems work out of equilibrium, meaning they are energy-consuming, dissipative and active. In recently years, chemists have made extensive efforts to design artificial active self-assembly systems, which will be pivotal to emulating and understanding life. Among various strategies, emerging approaches based on DNA nanotechnology have attracted a lot of attention. Structural- as well as dynamic-DNA-nanotechnology offer diverse tools with which to design building blocks and to shape their assembly behaviors. To achieve active self-assembly, a synergy of diverse DNA techniques is essential, including structural design, controllable assembly-disassembly, autonomous assembly, molecular circuits, biochemical oscillators, and so on. In this review, we introduce progress towards, or related to, active assembly via DNA nanotechnology. Dynamic DNA assembly systems ranging from passive assembly-disassembly systems, to autonomous assembly systems to sophisticated artificial metabolism and time-clocking oscillation systems will be discussed. We catalogue these systems from the perspective of free energy change with the reaction process. We end the review with a brief outlook and discussion.

Superatoms in materials science

Clusters are ensembles of bound atoms intermediate in size between a molecule and a bulk solid. Some of these clusters form stable units with atomically precise structures that give rise to collective behaviours that mimic those of traditional atoms, essentially functioning as ‘superatoms’. Such superatoms are exciting, nanoscale building blocks for materials design. Sustained synthetic and theoretical efforts over the past 40 years have created a vast library of chemically tuneable superatoms that display unique physical and chemical properties. The use of superatoms as building blocks for materials offers opportunities to design materials with tailored functionalities; however, this potential has only begun to be realized in the past few years. The assembly of superatomic crystals presents numerous challenges, including the design of suitable building blocks, control of the self-assembly process, promotion of strong inter-superatom coupling and understanding the resulting collective properties. In this Review, we assess recent advances in meeting these challenges by focusing on metal chalcogenide and carbon-based clusters (for example, fullerenes) as superatomic building blocks. Molecular clusters can be used as tuneable, superatomic building blocks to create new functional materials. This Review outlines the synthesis and assembly of superatoms into superatomic crystals and the resulting collective material properties.

Analysis of the Possibility of the Polymeric Aggregates Use in the Design of Building Block

Analysis of the Possibility of the Polymeric Aggregates Use in the Design of Building Block

Finite element analysis of building block ark Strength Analysis and Design of Building Block Ark Based on Finite Element

The research on the building block ark can be divided into two key issues: first, the hydrodynamic performance analysis of the building block ark, the main content is to study the hull shape and main scale of the building block ark. The second is the square of blocks.The strength analysis of the boat is mainly to study the overall structure and local strength of the building block ark. This article will explore the Lord.The content is the structural strength analysis of building block ark.

Mechanical Interlocking of Macrocycles in Different Sequences

Sequence isomerism is fundamental to the storage, transfer and expression of information in (bio)macromolecules and artificial polymers. Realization of sequence-specific properties in mechanically bonded molecules is extremely challenging due to the huge synthetic difficulty in the precise and controllable non-covalent interlocking of constitutionally different macrocycles in specific orders within a rotaxane or catenane. This Synpacts article highlights how sequence isomers of multicomponent rotaxanes and catenanes can be obtained by novel synthetic strategies and careful building block design.

Fluorine‐Substituted Benzotriazole Core Building Block‐Based Highly Efficient Hole‐Transporting Materials for Mesoporous Perovskite Solar Cells

Two novel donor–accepter–donor structured hole‐transporting materials based on fluorine‐substituted benzotriazole (BTA) core building blocks (2FBTA‐1 and 2FBTA‐2) are designed and synthesized through molecular regulation. Applying these materials into perovskite solar cells, power conversion efficiencies of 7.55% and 17.94% are obtained for 2FBTA‐1 and 2FBTA‐2, respectively. The better photovoltaic performance of 2FBTA‐2 is attributed to its more suitable energy level, more planar molecular configurations, and higher hole mobility. Moreover, the devices with 2FBTA‐2 as hole transport material (HTM) show good stability in air. The results indicate that BTA is a promising building block for future HTM design.

Building Block Design for Minimizing Defects in the Construction of Two-Dimensional Covalent Organic Frameworks.

Polymerization of monomers into two-dimensional covalent organic frameworks with precise porous structures exhibits desired catalytic, gas separation, and optoelectronic properties. However, the defects arising from covalent bonding in a polymerization process always result in amorphous films with small crystalline domains or polycrystalline powders. It is still a tremendous challenge to synthesize high-quality crystalline products, even single crystals with a large size over the micrometer scale. In this work, we propose a general strategy of building block design to reduce the defects during growth of two-dimensional covalent organic frameworks. We demonstrate that the building block with a hexagonal pore unit, i.e., a hexamer, could greatly decrease defects by directional uniform growth in polymerization, while monomer, dimer, and trimer building blocks form more defects due to linear growth. Our work provides a new strategy to construct superlarge single crystals in practical applications by combining building block design and growing dynamics control.

Distortion Analysis of $RC$ Integrators With Wideband Input Signals

The integrator is an important building block in circuit design and its transfer characteristic is inherently frequency-dependent. When it is implemented as an $RC$ op-amp circuit, a nonlinear element (the amplifier) is placed within a frequency-dependent feedback loop. Conventional techniques allow us to obtain the nonlinear error easily at certain frequencies only. Furthermore, when the integrator is periodically reset, the circuit is not in steady-state and conventional techniques assuming a steady-state behavior do not apply. It is not obvious how the actual error relates to the circuit parameters when the integrator is driven with a wideband signal. In this paper we present an approach to quickly estimate the normalized mean squared error (NMSE) as a function of the circuit and signal parameters. We show that, to first-order, the NMSE is proportional to the ratio of the signal bandwidth and the dominant pole of the integrator. For an integrator with reset, the signal builds up from zero and results in an additional, integration-time dependent NMSE reduction.

Python based open source design framework for integrated nanophotonic and superconducting circuitry with 2D-3D-hybrid integration

The efficient investigation of integrated photonic and superconducting circuitry relies on the flexible design of masks for the lithography steps. While commercial software packages for high-end design are commonly employed, for scientific users, such software systems are often financially exclusive and thus custom solutions are needed. Here we present a flexible open source Python framework that allows mask generation of integrated circuitry by easy-to-learn Python scripting. The framework is designed to facilitate the design of new photonic building blocks, since it allows defining the geometry by reusing existing parts or direct design using geometric objects. Through the use of existing and user-defined building blocks, complex integrated circuits can be created in a convenient fashion. We illustrate the capabilities of the framework by realizing hybrid nanophotonic-superconducting circuits, as well as hybrid 2D-3D nanophotonic circuits through multi-step nanofabrication. Because all design parameters can be defined by the user, the framework is not limited to a particular platform and can rapidly be adapted for new applications.

Dual-Gated MoS2 Neuristor for Neuromorphic Computing.

The field of neuromorphic computing systems has been through enormous progress in recent years, whereas some issues are still remaining to be solved. One of the biggest challenges in neuromorphic circuit designing is the lack of a robust device with functions comparable to or even better than the metal-oxide-semiconductor field-effect transistor (MOSFET) used in traditional integrated circuits. In this work, we demonstrated a MoS2 neuristor using a dual-gate transistor structure. An ionic top gate is designed to control the migration of ions, while an electronic back gate is used to control electronic migration. By applying different driving signals, the MoS2 neuristor can be programmed as a neuron, a synapse, or an n-type MOSFET, which can be seen as a fundamental building block in the neuromorphic circuit design. The MoS2 neuristor provides viable solutions for future reconfigurable neuromorphic systems and can be a promising candidate for future neuromorphic computing.

A building-block design for enhanced visible-light switching of diarylethenes

Current development of light-responsive materials and technologies imposes an urgent demand on visible-light photoswitching on account of its mild excitation with high penetration ability and low photo-toxicity. However, complicated molecular design and laborious synthesis are often required for visible-light photoswitch, especially for diarylethenes. Worse still, a dilemma is encountered as the visible-light excitation of the diarylethene is often achieved at the expense of photochromic performances. To tackle these setbacks, we introduce a building-block design strategy to achieve all-visible-light photochromism with the triplet-sensitization mechanism. The simply designed diarylethene system is constructed by employing a sensitizer building-block with narrow singlet-triplet energy gap (ΔEST) to a diarylethene building-block. A significant improvement on the photochromic efficiency is obtained as well as an enhanced photo-fatigue resistance over those under UV irradiation. The balance between the visible-light excitation and decent photochromism is thus realized, promoting a guiding principle for the visible-light photochromism.

Thomas F. Cash: A multidimensional innovator in the measurement of body image; Some lessons learned and some lessons for the future of the field

Accurate measurement of constructs under investigation is an often-overlooked ingredient of research. However, sound use of strategies to ensure valid and reliable assessment is the building block for any research design, data analysis, and outcome interpretation. In this paper, we note how Thomas F. Cash has pioneered and steered this process in the field of body image for over 30 years—in fact, in the inaugural issue of Body Image, the first article after the editorial introduction focused on measurement (see Thompson, 2004). In the current paper, we detail some of the seminal measures developed by Thomas Cash as well as update the common errors in the (mis)measurement of body image noted in Thompson (2004). The future of body image assessment is bright if we focus on the illumination of past work by Thomas Cash.

Synthesis of oxygen-deficient and monodispersed Pr doped CeO2 nanocubes with enhanced resistive switching properties

Monodispersed praseodymium (Pr) doped cerium oxide (CeO2) nanocubes (∼ 10 nm) were successfully synthesized via a facile two-phase solvothermal method and further assembled into a dense film through a drop-coating procedure for resistive switching applications. The XRD and Raman results showed that Pr element was successfully doped into the CeO2 lattice structure while maintaining the highly uniform nano-cubic structure. In addition, the concentration of oxygen vacancy in CeO2 nanocubes could be effectively modulated by varying dopant concentration evidenced by XPS and Raman analysis. The two-terminal structured device of Au/Pr doped CeO2/fluorine-doped tin oxide (FTO) exhibits stable resistive switching behaviour and ON/OFF endurance for more than 1000 cycles at a small operational voltage ranging from -0.6 to 1V. The present study may extend the potential of using praseodymium (Pr) doped cerium oxide nanocube in nanoscale building block for novelty 3D architectural memory and logic design in data-dependent applications such as artificial intelligence (AI) system and machine learning.