Yellow Spheres Research Articles

Artificial Intelligence Guided Studies of van der Waals Magnets (Adv. Theory Simul. 6/2023)

Searching for novel two-dimensional magnets using AI Intrinsic magnetic ordering in two dimensions was discovered in 2017 when a single layer of CrI3 and two layers of CrGeTe3 were shown to be ferromagnetic. In the research article, Rhone, Trevor David and coworkers harness AI to identify new two-dimensional magnetic materials and predict their magnetic and thermodynamic properties. Silver spheres represent transition metals. Yellow spheres represent the halogen atom: {Br, I}. Red spheres represent another halogen atom: {F, Cl}.

Charge Separation Enhancement Enables Record Photocurrent Density in Cu2ZnSn(S,Se)4 Photocathodes for Efficient Solar Hydrogen Production (Adv. Energy Mater. 19/2023)

Solar Hydrogen Production The image representing article number 2300215 by Shuo Chen and co-workers depicts photo-electrochemical water splitting that converts solar energy into hydrogen energy, presenting obvious hydrogen bubbles emerging from the photocathode surface to the electrolyte under light illumination. The blue columnar rods indicate high-quality Cu2ZnSn(S,Se)4 with large crystal grains and benign growth orientation. The yellow spheres denote photoelectrons, indicating efficient charge carrier generation, separation and transport.

Synthesis of lithium oxy-thiophosphate solid electrolytes with Li10GeP2S12 structure by a liquid phase process using 2-propanol.

Lithium oxy-thiophosphates isostructural with Li10GeP2S12 (LGPS) were synthesized by a liquid-phase process using 2-propanol as the solvent and Li2S and P2S5 as the starting materials. The XRD and 31P NMR results indicate that the synthesized compound has a slightly shrieked LGPS-type crystal structure where sulfur in PS43- is partially replaced by oxygen. The sample synthesized from the nominal composition of Li2S : P2S5 = 2.5 : 1 and at the annealing temperature of 300 °C exhibited the ionic conductivity of 1.6 × 10-4 S cm-1 at 25 °C. The synthesized solid electrolyte was found to be electrochemically stable in the potential range of 0-5 V, and also relatively stable under air with low relative humidity.

A novel phosphocholine-mimetic inhibits a pro-inflammatory conformational change in C-reactive protein.

C-reactive protein (CRP) is an early-stage acute phase protein and highly upregulated in response to inflammatory reactions. We recently identified a novel mechanism that leads to a conformational change from the native, functionally relatively inert, pentameric CRP (pCRP) structure to a pentameric CRP intermediate (pCRP*) and ultimately to the monomeric CRP (mCRP) form, both exhibiting highly pro-inflammatory effects. This transition in the inflammatory profile of CRP is mediated by binding of pCRP to activated/damaged cell membranes via exposed phosphocholine lipid head groups. We designed a tool compound as a low molecular weight CRP inhibitor using the structure of phosphocholine as a template. X-ray crystallography revealed specific binding to the phosphocholine binding pockets of pCRP. We provide invitro and invivo proof-of-concept data demonstrating that the low molecular weight tool compound inhibits CRP-driven exacerbation of local inflammatory responses, while potentially preserving pathogen-defense functions of CRP. The inhibition of the conformational change generating pro-inflammatory CRP isoforms via phosphocholine-mimicking compounds represents a promising, potentially broadly applicable anti-inflammatory therapy.

Bioinspired Vascular Stents with Microfluidic Electrospun Multilayer Coatings for Preventing In‐Stent Restenosis (Adv. Healthcare Mater. 17/2022)

Vascular Stents As shown in the cover picture, the bionic vascular stent prepared by Min Zhou, Yuanjin Zhao, and co-workers in article 2200965, is covered with double-layer nanofiber membranes made by electrospinning technology. The inner layer is loaded with Heparin-VEGF (shown in yellow spheres), which can be released into the lumen and promote endothelial repair. The outer membrane is loaded with rapamycin (shown in blue triangles), which can be released into the walls of blood vessels and prevents proliferation of vascular smooth muscle cells.

Exploring the Ligand Functionality, Electronic Band Gaps, and Switching Characteristics of Single Wells–Dawson‐Type Polyoxometalates on Gold (Adv. Mater. Interfaces 21/2022)

Polyoxometalates Polyoxometalates (POMs) equipped with vanadium centers offer outstanding opportunities for the development of switchable molecularly functionalized surfaces for non-binary, beyond-CMOS memory chips. In article number 2200461, Maria Glöß, Silvia Karthäuser, Kirill Yu. Monakhov, and co-workers report a room-temperature, multistate resistive switch based on a V3-substituted Wells-Dawson-type POM structure. The lilac spheres are unswitched POMs, the yellow sphere is switched POM.

Tuning the Interaction between Ruthenium Single Atoms and the Second Coordination Sphere for Efficient Nitrogen Photofixation (Adv. Funct. Mater. 12/2022)

Nitrogen Photofixation In article number 2112452, Xusheng Zheng and co-workers present N2 photofixation to ammonia over a CoO-supported Ru single-atom catalyst. The Ru-Co coordination between Ru single atoms (yellow spheres) and Co atoms (blue spheres) serves as an additional electron transfer channel. This channel promotes more photogenerated electrons to accumulate at Ru atoms, thus increasing photoelectron density and N2 photofixation performance over Ru active sites.

Tuning the local chemical environment of ZnSe quantum dots with dithiols towards photocatalytic CO2 reduction.

Sunlight-driven CO2 reduction to renewable fuels is a promising strategy towards a closed carbon cycle in a circular economy. For that purpose, colloidal quantum dots (QDs) have emerged as a versatile light absorber platform that offers many possibilities for surface modification strategies. Considerable attention has been focused on tailoring the local chemical environment of the catalytic site for CO2 reduction with chemical functionalities ranging from amino acids to amines, imidazolium, pyridines, and others. Here we show that dithiols, a class of organic compounds previously unexplored in the context of CO2 reduction, can enhance photocatalytic CO2 reduction on ZnSe QDs. A short dithiol (1,2-ethanedithiol) activates the QD surface for CO2 reduction accompanied by a suppression of the competing H2 evolution reaction. In contrast, in the presence of an immobilized Ni(cyclam) co-catalyst, a longer dithiol (1,6-hexanedithiol) accelerates CO2 reduction. 1H-NMR spectroscopy studies of the dithiol-QD surface interactions reveal a strong affinity of the dithiols for the QD surface accompanied by a solvation sphere governed by hydrophobic interactions. Control experiments with a series of dithiol analogues (monothiol, mercaptoalcohol) render the hydrophobic chemical environment unlikely as the sole contribution of the enhancement of CO2 reduction. Density functional theory (DFT) calculations provide a framework to rationalize the observed dithiol length dependent activity through the analysis of the non-covalent interactions between the dangling thiol moiety and the CO2 reduction intermediates at the catalytic site. This work therefore introduces dithiol capping ligands as a straightforward means to enhance CO2 reduction catalysis on both bare and co-catalyst modified QDs by engineering the particle's chemical environment.

Catalyzed combustion of a nanofluid fuel droplet containing polydopamine-coated metastable intermixed composite n-Al/CuO

The ignition and combustion characteristics of kerosene fuels containing polydopamine (PDA)-coated metastable intermixed composite (MIC) nano-aluminum (n-Al)/nano-copper oxide (CuO) are experimentally investigated, with a focus on the mass content of CuO in n-Al@PDA@CuO MICs. The total heat release of n-Al@PDA@CuO (2%) is found to be higher than that of the other n-Al@PDA@CuO samples. During the combustion of n-Al@PDA@CuO (2% and 5%)/kerosene droplets, a yellow flame appears around the agglomerate, which eventually evolves into a yellow light sphere with a diameter of around 5 mm after the kerosene flame extinguishes. Examination of the normalized droplet diameter curves and the morphology of combustion residues shows that the n-Al@PDA@CuO (2%)/kerosene droplet has the best all-around combustion characteristics. A mechanism is proposed for the enhancement of kerosene combustion by n-Al@PDA@CuO. Supporting data from thermogravimetry and differential scanning calorimetry (TG-DSC) measurements are presented. The findings and data in this study are expected to advance the development of new kerosene-based nanofluid fuels that meet the high energy demands of liquid propulsion systems.

Electrochemical Energy Storage: Direct Utilization of Photoinduced Charge Carriers to Promote Electrochemical Energy Storage (Small 21/2021)

This cover image shows that the as-prepared light-sensitive electrode materials are composed of CF@CuOx@NiCuOx nanoarrays, which can promote the pseudocapacitive property by photoinduced charge carriers. In the image, the standing rods represent the individual CuOx@NiCuOx, and the h+/e− highlighted in the yellow sphere demonstrates the charge separation/transfer occurring within the NiCuOx nanostructures under light irradiation (presented in article number 2008047 by Ting Zhu, Quanbing Liu, Qingyu Yan, and co-workers).

The osteogenic and bacterial inhibition potential of natural and synthetic compound loaded metal–ceramic composite coated titanium implant for orthopedic applications

Schematic illustration of the preparation, electrophoretic deposition, antibacterial and osteogenic bone regeneration abilities of the MHAP/ChN/GGe/GTN composite. Where, the green colored shape with red, yellow and blue spheres indicates the GGe.

Multiple Hydrogen Bond-Induced Structural Distortion for Broadband White-Light Emission in Two-Dimensional Perovskites

Low-dimensional hybrid lead-halide perovskites with broadband white-light emission upon near-UV excitation have attracted immense scientific interest due to their potential application for the next...

An extrinsic calibration method for multiple RGB-D cameras in a limited field of view

A 3D scanning system involving multiple RGB-D cameras has the potential to accelerate the reconstruction of an object and improve the measurement accuracy because it can capture an object in a comprehensive way. However, the extrinsic calibration of a multi-RGB-D-camera system is a fundamental and challenging problem, especially in a limited field of view. In this work, a system with four SR300 cameras on a platform with a size of approximately 0.64 m2 and an extrinsic calibration method assisted by a tower calibration pattern with circular markers in a limited field of view are proposed. The Hough transform algorithm is used to identify the centres of the circular markers in a colour image, and then the 3D coordinates are extracted by employing the alignment relationship between the colour image and the depth image. An improved adaptive cuckoo search (IACS) algorithm and unit quaternion are proposed to optimize the extrinsic parameters. The effectiveness of the IACS is verified by a comparison with the singular value decomposition (SVD), standard cuckoo search (CS) and two CS variant algorithms. In addition, the accuracy of the proposed extrinsic calibration method is verified by reconstructing and measuring a human foot and a cube box. The mean errors from the standard values of the length and width of the reconstructed foot mode are 0.18 cm and 0.13 cm, and the diameter of the yellow sphere are 0.17 cm, respectively. All of the experimental results show that the proposed extrinsic calibration method has a high calibration accuracy and good potential application prospects.

Contribution to the Study of the Iconography and Meaning of the Sun and Moon in Byzantine and Serbian Medieval Art with Special Interest in the Celestial Luminaries in the Church of St. Nicolas in Pelinovo (1716/1717)

The paper offers an analysis and а description of the scenes of heavenly visions in the art of Byzantium and medieval Serbia. The analysis of the scenes in which they appear, the iconographic features of heavenly luminaries, the specific contexts and the reasons for their depiction are discussed in the present paper. The author especially refers to two frescoes with the representations of the heavenly luminaries, the Sun and the Moon, in the painting of the church of St. Nicholas in the village of Pelinovo in Grbalj, Montenegro (1716/1717; ill. 1–4). Although the appearance of the celestial luminaries, their dimensions and placement in the iconographic program of the church as well as the reasons for their depiction are unique in Serbian painting done in the Byzantine tradition, to this day, the luminaries from Pelinovo did not represent the subject of the scientific research. For these reasons, this paper is dedicated to the above-mentioned issues.
 In the church of St. Nicholas in Pelinovo, the Moon is depicted en face, in a form of a large yellow sphere with large eyes and nose (ill. 2), without radial rays, while the Sun is portrayed in the same manner, in red color in a form of a fiery globe (ill. 1). The inscription next to the representation of the Sun is destroyed, while the Moon is marked as “Luna” in the Serbian redaction of Old-Slavonic. The Sun is shown as great luminary, and the Moon as a small luminary, according to the biblical narrative (Genesis 1:16). The heavenly aspect of the luminaries is determined by their depiction in the upper part fo the scene – on the blue ground, which symbolizes the sky as well as with their perfect spherical shape. As the figures of the Virgin, of Christ and of St. John the Forerunner in Pelinovo form a Deeisis, it is noticed that the heavenly luminaries are depicted in the scope of that composition (ill. 3–5). Therefore, the history of showing the Sun and the Moon in the Deesis scenes is considered in the paper. Apart from the above-said, it was concluded that the Sun is the symbol of Christ and the Moon the symbol of the Virgin Mary and the Church.

Conformational rearrangement of 1,2-d(GG) intrastrand cis-diammineplatinum crosslinked DNA is driven by counter-ion penetration within the minor groove of the modified site.

The major structural aberrations of DNA induced by a cis-diammineplatinum (II) 1,2-d(GG) intrastrand cross-link (CPT) have been known for decades. To gain deeper insights into the structural dynamics of the sequence-dependent DNA distortions adjacent to the CPT adduct, we employed molecular modeling and molecular dynamics (MD) simulations. The structural dynamics of native (N-DNA) and cisPt 1,2-d(GG) crosslinked (CPT-DNA) in the form of symmetric 36nt d(G2T15G*G*T15G2)●C2A15CCA15C2) oligonucleotide duplexes is compared. The selected sequence context enabled tracking of the origin of the DNA axis curvature at the YpR flexible points (N-DNA), the enhancement of axis bending, and further distortions due to steric/electrostatic perturbations arising from the CPT-crosslink. In addition to the known structural distortions of CPT-DNA: helix bend towards the major groove; local helix unwinding; high roll angle between cross-linked guanine bases; and adoption of A-form DNA on the 5'-side of the CPT-crosslink (TpG junction); our results show the existence of a singular irreversible and reproducible conformational rearrangement, not previously observed, resulting in two stable CPT-DNA1 and CPT-DNA2 conformers. The CPT-DNA2 conformation presents an enhanced DNA axis bend and a wider and shallower minor grove with increased solvent accessibility within the modified site. It is concluded that the polymorphous (unstable) DNA environment near the cisPt 1,2-d(GG) unit in synergy with specific dynamic events, such as prolonged minor groove retention of particular Na+ ions and water redistribution within the d(TG*G*T) site, together with the formation of extra and more stable H-bonds between Pt(NH3)2 amines and neighboring nucleotides, are cooperatively responsible for the initiation of the conformational rearrangement leading to the CPT-DNA2 conformer, which, surprisingly, closely resembles the HMGB1-bound CPT-DNA structure. Graphical abstract Superimposed averaged structures of normal (N-DNA, green) and cisplatin intrastrand cross-linked (CPT-DNA, orange). Global DNA axes: N-DNA (blue beads); CPT-DNA (red beads); PT (yellow sphere); crosslinked dGs viewed from the minor groove (bold).

Unexpected Reactivity of Red Phosphorus in Ionic Liquids

Invited for the cover of this issue are the groups of Michael Ruck and Eike Brunner at the Technische Universität Dresden, Germany. The cover image shows the enhanced reactivity of red phosphorus in the employed ionic liquid. Dissolved iodine molecules (yellow spheres) etch red phosphorus to form either molecular iodides like PI3 or phosphorus nanoparticles. The formation of the different species is monitored by liquid- (top) and solid-phase (bottom) NMR spectroscopy.

Unveiling the Pseudocapacitance of Ti2C Monolayer for High Performance Electrochemical Capacitor: a First-Principles Study

Two-dimensional (2D) transition-metal (TM) compound nanomaterials have been widely investigated for electrochemical capacitor due to their high-surface-area and large potential of providing pseudocapacitance. Very recently, a new family of 2D materials called MXenes were synthesized and have been considered as one of the most promising pseudocapacitor electrode materials with respect to both power density and energy density. In this work, we employ first-principles calculations to study the electronic structures and redox potential and diffusion of Li on Ti2C monolayer, a representative MXene, based on density functional theory (DFT). The electronic structures indicate a significant redox pseudocapacitance characteristics as an anode with the redox potential at about 0.25 V and 0.75 V refer to the standard hydrogen electrode. Moreover, the calculated metallic behavior and low Li ions diffusion barriers suggest that Ti2C monolayer would manifest a low resistance in charging/discharging process. Our findings provide an evidence that the Ti2C monolayer is a promising electrochemical capacitor electrode material. Figure a shows the crystal structure of Ti2C monolayer in the top view and side view. The Ti and C are revealed by yellow and blue spheres, respectively. On the top view, the lighter yellow spheres consist of the first layer with the third layer formed by dim ones. Relative dispositions of PDOS and Integral DOS of d-orbitals of Ti atoms in Ti2C monolayers are shown in Figure b both on the vacuum scale and with respect to the SHE reference. The dot dashed red lines indicate the Fermi level positions of Ti2C monolayer. The light blue region represents the electrolyte window. To deliberate the diffusion of Ti2C monolayer, three pathways (Figure c) and corresponding energy barriers (Figure d) are considered. Figure 1

Captures of <I>Rhagoletis indifferens</I> (Diptera: Tephritidae) and Nontarget Insects on Red Spheres Versus Yellow Spheres and Panels

Sticky red spheres can be used to capture western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae), but red spheres have not been definitively shown to be more attractive than yellow traps. The objective of this study was to compare fly captures on ammonia-baited red spheres and yellow spheres and panels so that sensitive detection traps for fly management can be identified. Nontarget insects could interfere with fly captures, so weights of nontarget insects on traps were also determined. Yellow spheres and panels generally caught more flies than red spheres. More males than females were caught on nearly all red and yellow traps. Saffron Thread, Marigold, Sunny Summer, and Yam Yellow spheres and panels were bright yellow and generally caught more flies, especially females, than Cherry Cobbler Red or Tartar Red spheres. Twenty Carat Yellow and Glorious Gold spheres and panels were less bright and caught fewer flies than bright yellow traps and similar numbers of flies as Tartar Red spheres, respectively. Dry weights of nontarget insects on at least one yellow trap type were greater than on red spheres in only 4 of 10 tests. Results show that bright yellow spheres and panels capture more R. indifferens than red spheres and do not consistently capture greater amounts of nontarget insects than red spheres, suggesting that they should be used instead of red spheres for detecting this fly.

Design and Synthesis of Cyclic ADP‐4‐Thioribose as a Stable Equivalent of Cyclic ADP‐Ribose, a Calcium Ion‐Mobilizing Second Messenger

Design and Synthesis of Cyclic ADP‐4‐Thioribose as a Stable Equivalent of Cyclic ADP‐Ribose, a Calcium Ion‐Mobilizing Second Messenger

A new naturally-occurring nanoporous copper sheet–silicate with 6482 cages related to synthetic “CuSH” phases

The structure of a new naturally-occurring nanoporous copper silicate of formula Na{sub 2}CaCu{sub 2}Si{sub 8}O{sub 20}·H{sub 2}O (disodium calcium dicopper octasilicate monohydrate) is reported and its relations to synthetic nanoporous “CuSH” compounds are discussed. The new phase is monoclinic C2/m with unit cell parameters a=12.2439(6) A, b=15.7514(4) A, c=10.6008(3) A, β=125.623(2)°, and V=1661.87(10) A{sup 3} (Z=4). The structure has been refined to R{sub 1}(all)=0.033, wR{sub 2}(all)=0.071, and GoF=1.090. In the double-sheet of SiO{sub 4} tetrahedra, 6{sup 4}8{sup 2} cages connect to form a chequer-board motif within which Na atoms and H{sub 2}O groups occupy channels. Each cage is occupied by 7-coordinated Na atom lying in a mirror plane. An intra-sheet corridor between the 6{sup 4}8{sup 2} cages is occupied by Na in 8-fold cuboidal coordination. The silicate skeleton is highly porous, with obvious channels and pathways for ion migration. The interlayer between double-sheets is occupied by CaO{sub 8}, CuO{sub 5} and NaO{sub 5}(H{sub 2}O) polyhedra. CuO{sub 5} polyhedra occur as rows of edge-sharing Cu{sub 2}O{sub 9} pairs connected by NaO{sub 5}(H{sub 2}O) octahedra and CaO{sub 8} square antiprisms. Both CuO{sub 5} and NaO{sub 5}(H{sub 2}O) polyhedra are features shared with closely-related synthetic “CuSH” phases of interest to the solid-state chemistrymore » community as potential nanoporous catalysts. However, Na{sub 2}CaCu{sub 2}Si{sub 8}O{sub 20}·H{sub 2}O is the only natural representative of this group of structures, and the only one to contain essential Ca. The discovery of Na{sub 2}CaCu{sub 2}Si{sub 8}O{sub 20}·H{sub 2}O points to a new group of CuSH-type phases containing alkaline-earth elements. Its close natural association and structural affinity with wesselsite SrCuSi{sub 4}O{sub 10} suggest the possibility of transformation between CuSH and gillespite-type phases, and thereby a route to synthesising alkaline-earth CuSH derivatives, so widening their potential as nanoporous catalysts. - Graphical abstract: Projection onto (010) of the structure of the natural nanoporous sheet silicate Na{sub 2}CaCu{sub 2}Si{sub 8}O{sub 20}·H{sub 2}O showing the double sheet of corner-linked SiO{sub 4} tetrahedra, intralayer Na and interlayer Na, Ca Cu and H{sub 2}O. Small green sphere Cu, large blue spheres Ca, orange purple and yellow small spheres Na, large grey sphere H{sub 2}O molecules. Bonds from inter/intralayer species to sheets have been omitted for clarity. - Highlights: • A new naturally-occurring nanoporous Cu sheet–silicate containing 6{sup 4}8{sup 2} cages. • A bridge between synthetic nanoporous CuSH phases and gillespite-type.« less