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In this work, zinc-doped carbon dots (Zn-CDs) were anchored on a three-dimensional wheel type paper-based microfluidic chip, and were decorated with 6-mercaptonicotinic acid (MNA) and L -cysteine (L -Cys) for highly sensitive and rapid fluorescence detection of Cu2+. Zn-CDs were first anchored on paper through the amide bonds between the carboxyl groups of the Zn-CDs and the amino groups of the paper. Afterwards, Zn-CDs were decorated with MNA and L -Cys, effectively preventing the Zn-CDs from aggregation. The nitrogen atom on the pyridine ring and the carboxylic acid groups in MNA and L -Cys coordinated with Cu2+ to form a nonfluorescent ground-state complex, causing the fluorescence quenching of the Zn-CDs. The three-dimensional rotary design could simplify the operation process and achieve simultaneous analysis of multiple samples with different concentrations. Under optimal conditions, the fluorescent sensor exhibits linear response for the determination of Cu2+ in the range from 0.1 to 60 μg L−1 with the detection limit (LOD) of 0.018 μg L−1. The proposed strategy provides a novel way for the highly sensitive detection of Cu2+ in a complex water environment. [ABSTRACT FROM AUTHOR]

Moisture is an important factor affecting the insulation properties of transformers. Due to the limitations of macroscopic experimental methods, the diffusion of water at oil-paper interface cannot be accurately measured. Therefore, molecular dynamics method was used in this work to establish oil-paper layer model of 105 atoms. Through jointly analysing the aggregation degree, diffusion coefficient, free volume as well as radial distribution function of water molecules, the diffusion mechanism of water molecules at oil-paper interface was studied. The results show that when the initial water content in paper was high, water molecules would accumulate at oil-paper interface to form the local high-water region during heating. The polarisation of the electric field strengthened the hydrogen bonding interaction between water molecules and increased the probability of occurrence of the high-water region. Meanwhile, electric field reduced the free volume and diffusion coefficient of water molecules and rendered its diffusion coefficient anisotropic. What’s more, when the electric field was combined with the temperature field, the electric field played a leading role in the diffusion of water molecules while the temperature field was less affected. Diffusion coefficients of water molecules at different temperatures from molecular dynamics simulations were well consistent with experimental results, which verified the rationality of the model. [ABSTRACT FROM AUTHOR]

The article reports on the use of the chelating agent ethylenediamine tetra acetic acid in removing unwanted stains and spots from paper objects. In order to be a chelating agent, a molecule must have two appropriate functional groups, each having a donor atom, having the capacity to combine a metal atom by donating a pair of electrons. It was discovered that the pH of pure cellulose paper remained neutral. No significant change after accelerated ageing at 105°C for 72 hour was found. Moreover, no change was discovered after iron staining.

The article reports on the 2009 Outstanding Conference Paper Award that was given to IEEE Nuclear and Space Radiation Effects Conference (NSREC) in Canada. The conference paper on radiation effects comprises upset cross-section obtained from accelerated testing with the use of both protons and ions. The paper also focuses on the understanding a diverse range of single event effects. In addition, test shows that upset cross-sections-per-bit was similar for both ions and proton.

The discovery over 100 years ago that cathode rays were composed of negatively charged corpuscles-subsequently named electrons-was an historic event in the development of science, demonstrating for the first time that particles smaller than atoms existed and initiating other investigations into the nature of matter, as well as marking the beginning of the electronics industry. The research investigations of J. J. Thomson, leading up to the crucial experiments identifying the particle and determining its charge-to-mass ratio as reported in the Philosophical Magazine, are here described. [ABSTRACT FROM AUTHOR]

The associability of artificial intelligence (AI) as a dual-use technology for nuclear material production (NMP) within the academic and practitioner communities remains widely neglected, and so a widening opportunity for AI to aid in illicit and covert non-peaceful applications exists. To address this emerging gap, this paper investigates the evolving and applicable uses of AI and finds broad evidence of its use to optimize performance, promote innovation, reduce costs, and enhance safety associated with the development and production of nuclear material. AI's use in this arena will, thereby, facilitate broader accessibility of peaceful uses of nuclear science and technology, while at the same time cause concerns that said improvements can aid the illicit development of nuclear weapons. As such, this paper advocates for a three-dimensional solution to manage the evolving dual-use concern of AI that involves advancing states-centric monitoring and regulation, promoting intellectual exchange between the nonproliferation sector and the AI industry, and encouraging AI industrial contributions. [ABSTRACT FROM AUTHOR]

Featured Application: This work provides a systematic way to produce a defect-free atom array of neutral atom platforms for quantum information processing. This paper aims to present an approach to address the atom rearrangement problem by developing Convolutional Neural Network (CNN) models. These models predict the coordinates for atom movements while ensuring collision-free transitions and filling all vacancies in the target array. The process begins with designing a cost function for the assignment problem that incorporates constraints to prevent collisions and guarantee vacancy filling. We then build and train CNN models using datasets for three different grid sizes: 10 × 10 ,   13 × 13 ,   and   21 × 21 . Our models achieve high accuracy in predicting atom positions, with individual position accuracies of 99.63%, 98.93%, and 97.24%, respectively, for the aforementioned grid sizes. Despite limitations in training larger models due to hardware constraints, our approach demonstrates significant improvements in speed and accuracy. The final section of the paper presents detailed accuracy results and calculation times for each model, highlighting the potential of CNN-based methods in optimizing atom rearrangement processes. [ABSTRACT FROM AUTHOR]

In this paper, the precipitation behavior and its effect on resistivity in a new type of nickel–iron-based alloy during short-term aging were investigated. During the aging process, the γ ′ phase increases in average size and decreases in number, with its area fraction fluctuating over time. This fluctuation is caused by the mismatch in the redissolution and growth rates of the γ ′ phase. As the area fraction of the γ ′ phase increases, the content of solute atoms in the matrix that scatter electrons decreases, lowering the resistivity of the alloy. Additionally, the continuous precipitation of M 23 C 6 at grain boundaries during aging causes the resistivity to gradually increase. This paper explains the fluctuation in the total amount of γ ′ phase during short-term aging and proposes a new method for characterizing the precipitation behavior of the γ ′ phase in the novel alloy using the relative trend of resistivity changes. [ABSTRACT FROM AUTHOR]

Provides information on the development of a model of multielectronic atoms by Werner Heisenberg. Experience of Werner during the World War I; Discussion on the Zeeman effect of the multiplets in weak fields analyzed in Werner's study; Introduction of a heuristic harmonic-oscillator model for sodium.

This paper reports an analysis on fractality using the experimental data of compound multiplicity (pions + target protons) distribution in 24Mg-AgBr interactions at 4.5 AGeV following the method proposed by F. Takagi. Takagi moments have been calculated for 2nd, 3rd, 4th, and 5th order in the emission angle and azimuthal angle space. The results of our study reveal the multi-fractal structure of compound multiplicity distribution. [ABSTRACT FROM AUTHOR]

In this paper, we explore the molecular basis of combining photodynamic therapy (PDT), a light-triggered targeted anticancer therapy, with the traditional chemotherapeutic properties of the well-known cytotoxic agent gemcitabine. A photosensitizer prerequisite is significant absorption of biocompatible light in the visible/near IR range, ideally between 600 and 1000 nm. We use highly accurate multiconfigurational CASSCF/MS-CASPT2/MM and TD-DFT methodologies to determine the absorption properties of a series of gemcitabine derivatives with the goal of red-shifting the UV absorption band toward the visible region and facilitating triplet state population. The choice of the substitutions and, thus, the rational design is based on important biochemical criteria and on derivatives whose synthesis is reported in the literature. The modifications tackled in this paper consist of: (i) substitution of the oxygen atom at O2 position with heavier atoms (O → S and O → Se) to red shift the absorption band and increase the spin–orbit coupling, (ii) addition of a lipophilic chain at the N7 position to enhance transport into cancer cells and slow down gemcitabine metabolism, and (iii) attachment of aromatic systems at C5 position to enhance red shift further. Results indicate that the combination of these three chemical modifications markedly shifts the absorption spectrum toward the 500 nm region and beyond and drastically increases spin–orbit coupling values, two key PDT requirements. The obtained theoretical predictions encourage biological studies to further develop this anticancer approach. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm. It provides information about the articles and papers included in the issue, as well as details about the journal's focus and editorial board. The journal aims to advance the understanding and design of solid-state and crystalline materials. It welcomes studies on molecular behavior within crystals, control of crystal growth, and the engineering of crystal structures. The document also includes information for authors on how to submit material for publication. [Extracted from the article]

Accurate atom mapping, which establishes correspondences between atoms in reactants and products, is a crucial step in analyzing chemical reactions. In this paper, we present a novel end-to-end approach that formulates the atom mapping problem as a deep graph matching task. Our proposed model, AMNet (Atom Matching Network), utilizes molecular graph representations and employs various atom and bond features using graph neural networks to capture the intricate structural characteristics of molecules, ensuring precise atom correspondence predictions. Notably, AMNet incorporates the consideration of molecule symmetry, enhancing accuracy while simultaneously reducing computational complexity. The integration of the Weisfeiler-Lehman isomorphism test for symmetry identification refines the model's predictions. Furthermore, our model maps the entire atom set in a chemical reaction, offering a comprehensive approach beyond focusing solely on the main molecules in reactions. We evaluated AMNet's performance on a subset of USPTO reaction datasets, addressing various tasks, including assessing the impact of molecular symmetry identification, understanding the influence of feature selection on AMNet performance, and comparing its performance with the state-of-the-art method. The result reveals an average accuracy of 97.3% on mapped atoms, with 99.7% of reactions correctly mapped when the correct mapped atom is within the top 10 predicted atoms. Scientific contribution The paper introduces a novel end-to-end deep graph matching model for atom mapping, utilizing molecular graph representations to capture structural characteristics effectively. It enhances accuracy by integrating symmetry detection through the Weisfeiler-Lehman test, reducing the number of possible mappings and improving efficiency. Unlike previous methods, it maps the entire reaction, not just main components, providing a comprehensive view. Additionally, by integrating efficient graph matching techniques, it reduces computational complexity, making atom mapping more feasible. [ABSTRACT FROM AUTHOR]

Formal Concept Analysis (FCA) is an applied branch of lattice theory, widely used in computer science that derives implicit relationships between objects described through a set of attributes on the one hand and these attributes on the other. Any finite lattice can be generated by a formal concept, which can be obtained from the formal context of objects and attributes. In this paper, given a finite lattice L with /(L)/ = /(L)/ = n where n is the number of atoms in the Boolean lattice Bn, we construct a formal context obtained by substitution sum ... and study the structural properties of the lattice BS(L) generated by the above substitution sum. Interestingly, the lattice L and the Boolean lattice Bn remain as separate entities in the lattice BS(L). Further, we have proved that the lattice BS(L) is complemented. [ABSTRACT FROM AUTHOR]

Urease may rapidly hydrolyze urea, causing a significant amount of ammonia to be released and decreasing the efficacy of urea fertilizers. However, urease inhibitors (UIs) can prevent the interaction between urease and urea, allowing crops to absorb ammonium nitrogen for an extended period of time. In this paper, by using different O-donor second auxiliary ligands, we have designed and synthesized two Cu-based coordination polymers (Cu-CPs) to operate as UIs by combining two aromatic carboxylic acids and a bis-pyridine-bis-amide ligand, which show excellent urease inhibitory activity. Cu-CP-1 has an obvious inhibitory effect on the inhibitory activity against jack bean urease, with the IC50 of 1 being 0.83 ± 0.01 μM while the IC50 value for Cu-CP-2 was 2.53 ± 0.01 μM, respectively. Furthermore, inhibitory activity against urease, kinetics, molecular docking, and comparisons of the title Cu-CPs and other complex-based materials have been comprehensively investigated. More importantly, the bridging atoms of μ2-OH and μ2-Cl play important roles in urease inhibition activity. The structure–function relationships were further discussed and indicate that Cu-CPs can be used as a kind of UI. [ABSTRACT FROM AUTHOR]

The persistent problem posed by the glass transition is to develop a general atomic level description of amorphous solidification. The answer proposed in this paper is to measure a configuration's capacity to restrain the motion of the constituent atoms. Here, we show that the instantaneous normal modes can be used to define a measure of atomic restraint that accounts for the difference between fragile and strong liquids and the collective length scale of the supercooled liquid. These results represent a significant simplification of the description of amorphous solidification and provide a powerful systematic treatment of the influence of microscopic factors on the formation of an amorphous solid. [ABSTRACT FROM AUTHOR]

In this paper, the unconventional light‐matter interactions between giant atoms and structured baths (i.e., lattices) are studied with either Hermitian or non‐Hermitian next‐nearest‐neighbor coupling terms. Essentially different dynamics of the atoms and the propagating field in the Hermitian and non‐Hermitian cases is revealed, which can be further engineered by tuning parameters such as the atomic transition frequency and the (synthetic) magnetic field associated to the coupling terms. The next‐nearest‐neighbor couplings play an important role in controlling the emission direction and the field distribution in the lattice, thus providing opportunities for tailoring exotic dipole–dipole interactions. The results in this paper have potential applications in, e.g., engineering unconventional quantum networks and simulating quantum many‐body systems. [ABSTRACT FROM AUTHOR]

In 1967, Grünbaum conjectured that any d-dimensional polytope with d + s ⩽ 2 d vertices has at least ϕ k (d + s , d) = d + 1 k + 1 + d k + 1 - d + 1 - s k + 1 k-faces. This conjecture along with the characterization of equality cases was recently proved by the author (A proof of Grünbaum's lower bound conjecture for general polytopes. Israel J. Math. 245(2), 991–1000 (2021)). In this paper, several extensions of this result are established. Specifically, it is proved that lattices with the diamond property (e.g., abstract polytopes) and d + s ⩽ 2 d atoms have at least ϕ k (d + s , d) elements of rank k + 1 . Furthermore, in the case of face lattices of strongly regular CW complexes representing normal pseudomanifolds with up to 2d vertices, a characterization of equality cases is given. Finally, sharp lower bounds on the number of k-faces of strongly regular CW complexes representing normal pseudomanifolds with 2 d + 1 vertices are obtained. These bounds are given by the face numbers of certain polytopes with 2 d + 1 vertices. [ABSTRACT FROM AUTHOR]

The given text appears to be a scientific article or research paper that provides detailed information on the crystal structures of various mixed-valence gold compounds. The compounds contain gold(I) and gold(III) atoms, as well as different ligands such as sulfur, phosphorus, and selenium. The text discusses the structures, compositions, and supramolecular features of the compounds, including bond lengths, angles, and interionic contacts. It also provides information on the synthesis and characterization of the compounds, as well as their crystallographic data and refinement details. Overall, the text is a valuable resource for researchers studying the properties and structures of gold compounds. [Extracted from the article]

The interface connects the reinforced phase and the matrix of materials, with its microstructure and interfacial configurations directly impacting the overall performance of composites. In this study, utilizing seven atomic layers of Mg(0001) and Ti(0001) surface slab models, four different Mg(0001)/Ti(0001) interfaces with varying atomic stacking configurations were constructed. The calculated interface adhesion energy and electronic bonding information of the Mg(0001)/Ti(0001) interface reveal that the HCP2 interface configuration exhibits the best stability. Moreover, Si, Ca, Sc, V, Cr, Mn, Fe, Cu, Zn, Y, Zr, Nb, Mo, Sn, La, Ce, Nd, and Gd elements are introduced into the Mg/Ti interface layer or interfacial sublayer of the HCP2 configurations, and their interfacial segregation behavior is investigated systematically. The results indicate that Gd atom doping in the Mg(0001)/Ti(0001) interface exhibits the smallest heat of segregation, with a value of −5.83 eV. However, Ca and La atom doping in the Mg(0001)/Ti(0001) interface show larger heat of segregation, with values of 0.84 and 0.63 eV, respectively. This implies that the Gd atom exhibits a higher propensity to segregate at the interface, whereas the Ca and La atoms are less inclined to segregate. Moreover, the electronic density is thoroughly analyzed to elucidate the interfacial segregation behavior. The research findings presented in this paper offer valuable guidance and insights for designing the composition of magnesium-based composites. [ABSTRACT FROM AUTHOR]

It is well-known that the pseudodifferential operator with the symbol in Bony class, a subset of S 1 , 1 0 (R n) , is bounded on L 2 (R n) . The main purpose of this paper is to extend the classical results to multi-parameter case, i.e., to discuss the boundedness on L 2 (R n 1 + n 2 ) and on h p (R n 1 × R n 2) (0 < p ≤ 1) of multi-parameter pseudodifferential operator with symbol satisfying multi-parameter Bony conditions. [ABSTRACT FROM AUTHOR]