Databases of 2D material-substrate interfaces and 2D charged building blocks

Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188.

A novel 300 kW arc plasma inverter system based on hierarchical controlled building block structure

To date, the high power arc plasma technology is widely used. A next generation high power arc plasma system based on building block structure is presented. The whole arc plasma inverter system is composed of 12 paralleled units to increase the system output capability. The hierarchical control system is adopted to improve the reliability and flexibility of the high power arc plasma inverter. To ensure the reliable turn on and off of the IGBT module in each building block unit, a special pulse drive circuit is designed by using pulse transformer. The experimental result indicates that the high power arc plasma inverter system can transfer 300 kW arc plasma energy reliably with high efficiency.

Preparation, Structure and Properties of 3D Supramolecular Architecture, on the Basis of Hydrogen Bonds and π-π Stacking Between 2D Layers, with Windmill Building Blocks

A novel three-dimensional（3D） supramolecular architecture, {[Nd（OH-BDC）（OH-HBDC）（H2O）2]·2HaO）n（1） （OH-H2BDC=5-hydroxyisophthalic acid）, which was formed through hydrogen bonds and π-π stacking between two-dimensional（2D） layers, was hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Windmill building blocks, which consist of two nine-coordinated metal centers and four OH-H2BDC groups are connected through two carboxyl groups, to lead to a one-dimensional infinite inorganic chain（… M--O--C--O--M…） along the [100] direction. An observed intense blue luminescence with an emission band peaked at 390 nm for compound 1 may results from ligand-to-metal charge transfer（LMCT）. Variable-temperature magnetic susceptibility of compound 1 was investigated and the value was deviated from the Curie-Weiss law.

Two Chiral Building Blocks for the Stereocontrolled Synthesis of Anti-and Syn-1,3-Diols

Two chiral building blocks 1 and 2 for anti-and syn-1, 3-diols has been achieved in 8 steps and 7 steps respectively, starting from the readily available and inexpensive D (+)-xylose 3.

STUDIES ON THE SYNTHESIS OF RABDOSIA DITERPENOID Ⅱ,PREPARATION OF A KEY BUILDING BLOCK,α,β-UNSATURATED LACTONE

The main half molecule(4a)of the trichorabdal B(1) was synthesized from pentadienol(6).The key step is the intramolecular Diels-Alder reaction of 8.

Biobased Vanillic Acid and Ricinoleic Acid: Building Blocks for Fully Renewable Copolyesters

New fully biobased polyether/esters have been synthesized by a one-pot polymerization reaction of ricinoleic acid(RA),vanillic acid(VA)and ethylene carbonate(EC).In particular,EC selectively reacts with the phenolic group of VA to obtain in-situ 4-(2-hydroxyethoxy)-3-methoxybenzoate(EV),suitable for subsequent copolymerization with RA.The procedure was carried out in a single step,without any solvent.Chemical structure and thermal properties of the new materials were studied in order to explore relationships between composition and final performances.The combination of EV,bearing a rigid aromatic structure,with RA,characterized by high flexibility and potential biocidal activity,allows the production of a novel class of fully biobased aliphatic-aromatic polymers presenting tuneable thermal properties and suitable for a range of applications,for example,in active packaging and biomedical fields.

(Z)-ETHYL 3-BROMO-4,4,4-TRIFLUORO-2-BUTENOATE AS A NOVEL CF_3-CONTAINING BUILDING BLOCK: Its Preparation and Pd-Catalysed Reaction with Alkynes and Organozinc Reagents

A novel CF_3-containing building block, (Z)-ethyl 3-bromo-4,4,4-trifluoro-2-butenoate, was easily prepared from CF_3CBr_3, the former reacted with alkynes Or organozinc reagents in the presence of Pd complexes to afford useful CF_3-containing intermediates in good yield.

Compliant semiconductor scaffolds: building blocks for advanced neural interfaces

Neuroscience,neuroprosthetics and neural regeneration would benefit from more adequate interfacing devices.To understand how neurons communicate,process information and control behavior,researchers need to monitor nerve cell activity with high specifity and high spatio-temporal resolution.Neural prostheses require minimally invasive-implantable devices to re- place lost function, and bypass dysfunctional pathways in the nervous system. Devices built to repair damaged nerves have to support and promote regeneration of host neurons through an injured area. Finally, as neuromodulation is being elevated from last resort to first choice treatment for an increasing number of conditions, implantable devices able to perform targeted regu- lation of neural activity are needed. Recent advances in device miniaturization, materials engineering, and nanotechnology are enabling development of an increasing number of devices that effectively interface with neural circuits. Wireless spinal cord and deep brain stimulators, retinal and cochlear implants, high density electrodes arrays for neural recording have already proven to significantly impact fundamental research in neuro- science, as well as individuals＇ quality of life.

Appropriate schemata and building blocks

Appropriate schemata as a novel concept to characterize building blocks are introduced, and then, the traits of appropriate schemata are presented. The effects of building blocks by search operators are analyzed. Hence, the experiments on RR-8X8 are employed to verify that appropriate schemata construct the building blocks. The validity of appropriate schemata and building blocks from the views of theory and practice is presented.

Solving Job-Shop Scheduling Problems by Genetic Algorithms Based on Building Block Hypothesis

In this paper, we propose a new genetic algorithm for job-shop scheduling problems （JSP）. The proposed method uses the operation-based representation, based on schema theorem and building block hypothesis, a new crossover is proposed ： By selecting short, low order highly fit schemas to genetic operator, the crossover can exchange meaningful ordering information of parents effectively and can search the global optimization. Simulation results on MT benchmark problem coded by C ＋ ＋ show that our genetic operators are very powerful and suitable to job-shop scheduling problems and our method outperforms the previous GA-based approaches.

Autoclaved Aerated Concrete Block Prefabricated Multi-Storey Building Technology

In active response to the national requirements of promoting green building materials and developing prefabricated buildings,it is necessary to continuously optimize and reasonably employ relevant technologies.Autoclaved aerated concrete block prefabricated multi-storey building technology is a new technology,which will not only effectively realize green environmental protection in construction engineering,but also promote the further development of prefabricated buildings.Therefore,this paper analyzes the autoclaved aerated concrete block prefabricated multi-storey building technology for future references.

A research on building block type miniature harvester

In this invention, the procedure of cutting, conveying, threshing and transporting stalks are carried out by a set of conveying chains ( see figure). The axis of the main drum 2 is placed horizontally transverse (vertical to the forward direction). The upper and the lower conveying chains 8, 10 as well as cutterbar 11 are mounted in the lower part of the axial feed opening. Several star well 9 and plastic stalk-pressing rod are filled at the front of the lower conveying chain, and a spring stalk pressing assembly at the rear. The residue after threshing is discharged by star seels 18, 34. The staiks are placed near the cutterbar 11. Once the stalks are cut off by the cutterbar, they

Building Blocks

Building Blocks Funeka Yazini AprilAfrican governments, not the Americans or the Chinese, have the key responsibility to become the drivers of their own industrial and agricul- tural development. There- fore, it is urgent that African governments prioritize the objectives of the Johannes- burg Summit of the Forum on China-Africa Cooperation （FOCAC） domestically and regionally.

Synthesis of an Anti-1,3-Diol Type Chiral Building Block

A chiral building block, anti-1,3-diol 2, has been synthesized in 7 steps, starting from readily available and inexpensive D-(+)-xylose.

A highly reduced Mo_(74) polyoxometalate featuring high proton conductivity accessed by building block strategy

Highly reduced polyoxometalates(POMs) are predicted to be used as rather high energy density materials;however,it still suffers from the limited cluster species and reduction ratio.Here we demonstrate that it is possible to employ the building block strategy to generate a highly reduced polyoxomolybdate(C_(2)H_(8)N)_(14)(NH_(4))_(4)H_(14)[Mo_(48)-ⅤMo_(26)ⅥO_(202)(OH)_(12)(SO_(4))_(6)]·46H_(2)O(Mo_(74)).The fundamental Mo-based{Mo_x}(x=4,5,and 6) building blocks,which are templated by tetra-coordinated anions{MoO_(4)}or{SO_(4)},not only lay foundation for the formation of Mo_(74) featuring an unprecedented reduction ratio of 65%,but also give rise to SBBs-mediated(secondary building blocks) supramolecular dense packing interactions among the isolated Mo_(74) clusters that are favorable for proton conduction.Remarkably,high proton conductivity(2.04×10^(-2)S cm^(-1)) had been realized at 50℃ and 90% relative humidity,revealing one of the well-known POMs-based crystalline proton conducting materials.This result highlights that this building block approach possesses great potential in producing highly reduced POM systems that can achieve controllable reduced ratio and desirable properties.

Synthesis and Crystal Structure of a 2D Cu Framework Constructed from Dinuclear Building Units

A novel 2D Cu coordination polymer [Cu4(pca)4(H2O)2(DMSO)2·2DMSO·2H2O]n(2, H2 pca = pyrazole-3-carboxylic acid) has been prepared by dissolving a dinuclear Cu complex Cu2(py)3(pca)2(H2O)·(H2O)(1) in DMSO solution and structurally characterized by X-ray diffraction. The polymer crystallizes in space group P1 with a = 9.538(3), b = 9.714(3), c = 10.765(3) A, α = 86.492(6), β = 84.007(7), γ = 82.592(6)o, Mr = 1079.04, V = 982.4(5) A3, Z = 1, Dc = 1.824 g/cm3, μ = 2.425 mm-1 and F(000) = 548. The final refinement gave R = 0.0785 and w R = 0.1940 for 2787 reflections with I 】 2σ(I). The structure of 2 consists of Cu4(pca)4(H2O)2(DMSO)2·2DMSO·2H2O units, which can be viewed as two dinuclear subunits of Cu2(pca)2(H2O)2 and Cu2(pca)2(DMSO)2 connected to each other alternately, with solvent DMSO and H2 O molecules around. The framework features a grid-like topology, with the walls of the grids composed of Cu4(pca)4 units, and the coordinated solvent molecules trapped in the grids.

A Simple Building Block with Noncovalently Conformational Locks towards Constructing Low-Cost and High-Performance Nonfused Ring Electron Acceptors

Nonfused ring electron acceptors(NFREAs)have attracted much attention due to their concise synthetic routes and low cost.However,developing high-performance NFREAs with simple structure remains a great challenge.In this work,a simple building block(POBT)with noncovalently conformational locks(No CLs)was designed and synthesized.Single-crystal X-ray study indicated the presence of S…O NOCLs in POBT,thus enabling it to possess a coplanar conformation comparable to that of fused-ring CPT.Two novel NFREAs based on CPT and POBT were developed,namely TT-CPT and TT-POBT,respectively.Besides,TT-POBT possessed a smaller Stokes shift and a reduced reorganization energy compared with TT-CPT,indicating the introduction of S…O No CLs can enhance the molecular rigidity even if simplifying the molecular structure.As a result,the TT-POBT-based PSC device afforded an impressive power conversion efficiency of 11.15%,much higher than that of TT-CPT counterpart(7.03%),mainly resulting from the tighterπ-πstacking,improved and balanced charge transport,and more favorable film morphology.This work demonstrates the potential of the simple building block POBT with No CLs towards constructing low-cost and highperformance NFREAs.

Structural survey of metal-covalent organic frameworks and covalent metal-organic frameworks

This review offers an overview of the latest developments in metal-covalent organic framework(MCOF)and covalent metal-organic framework(CMOF)materials,whose construction entails a combination of reversible coordination and covalent bonding adapted from metal-organic frameworks(MOFs)and covalent organic frameworks(COFs),respectively.With an emphasis on the MCOF and CMOF structures,this review surveys their building blocks and topologies.Specifically,the frameworks are classified based on the dimensions of their components(building blocks),namely,discrete building blocks and one-dimensional infinite building blocks.For the first category,the materials are further divided into collections of two-and three-dimensional networks based on their topologies.For the second category,the recently emerging MCOFs with woven structures are covered.Finally,the state-of-the-art in MCOF and CMOF chemistry has been laid out for promising avenues in future developments.