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<jats:p>The aggregation of <jats:italic>β</jats:italic>-amyloid (A<jats:italic>β</jats:italic>) protein into toxic intermediates and mature fibrils is considered to be one of the main causes of Alzheimer’s disease (AD). Small molecules as one of blockers are expected to be the potential drug treatment for the disease. However, the nucleation process in molecular assembly is less informative in the literatures. In this work, the formation of A<jats:italic>β</jats:italic>(16-22) peptides was investigated with the presence of small molecule of fast green (FG) at the initial aggregation stage. The results exhibited the tunable inhibitory ability of FG molecules on A<jats:italic>β</jats:italic>(16-22) peptides. Atomic force microscopy (AFM) demonstrated that the inhibitory effect would be dependent on the dose of FG molecules, which could delay the lag time (nucleation) and form single layer conjugates. Spectral measurements further showed that the <jats:italic>β</jats:italic>-sheet secondary structure of A<jats:italic>β</jats:italic>(16-22) reduced dramatically after the presence of FG molecules. Instead, non-<jats:italic>β</jats:italic>-sheet nanosheets were formed when the FG/A<jats:italic>β</jats:italic>(16-22) ratio reached 1:1. In addition, the cytotoxicity of aggregates reduced greatly with the presence of FG molecules compared with the A<jats:italic>β</jats:italic>(16-22) fibrils. Overall, this study provided a method for suppressing the toxic amyloid aggregates by FG molecules efficiently, and also showed a strategy for fabrication of two-dimensional materials by small molecules.</jats:p>

<jats:p>The digitization, informatization, and intelligentization of physical systems require strong support from big data analysis. However, due to restrictions on data security and privacy and concerns about the cost of big data collection, transmission, and storage, it is difficult to do data aggregation in real-world power systems, which directly retards the effective implementation of smart grid analytics. Federated learning, an advanced distributed learning method proposed by Google, seems a promising solution to the above issues. Nevertheless, it relies on a server node to complete model aggregation and the framework is limited to scenarios where data are independent and identically distributed. Thus, we here propose a serverless distributed learning platform based on blockchain to solve the above two issues. In the proposed platform, the task of machine learning is performed according to smart contracts, and encrypted models are aggregated via a mechanism of knowledge distillation. Through this proposed method, a server node is no longer required and the learning ability is no longer limited to independent and identically distributed scenarios. Experiments on a public electrical grid dataset will verify the effectiveness of the proposed approach.</jats:p>

<jats:p>Formamidinium lead triiodide (FAPbI<jats:sub>3</jats:sub>) is a research hotspot in perovskite photovoltaics due to its broad light absorption and proper thermal stability. However, quite a few researches focused on the stability of the FAPbI<jats:sub>3</jats:sub> perovskite precursor solutions. Besides, the most efficient FAPbI<jats:sub>3</jats:sub> layers are prepared by the spin-coating method, which is limited to the size of the device. Herein, the stability of FAPbI<jats:sub>3</jats:sub> perovskite solution with methylammonium chloride (MACl) or cesium chloride (CsCl) additive is studied for preparing perovskite film through an upscalable blade-coating method. Each additive works well for achieving a high-quality FAPbI<jats:sub>3</jats:sub> film, resulting in efficient carbon electrode perovskite solar cells (pero-SCs) in the ambient condition. However, the perovskite solution with MACl additive shows poor aging stability that no <jats:italic>α</jats:italic>-FAPbI<jats:sub>3</jats:sub> phase is observed when the solution is aged over one week. While the perovskite solution with CsCl additive shows promising aging stability that it still forms high-quality pure <jats:italic>α</jats:italic>-FAPbI<jats:sub>3</jats:sub> perovskite film even the solution is aged over one month. During the solution aging process, the MACl could be decomposed into methylamine which will form some unfavored intermediated phase inducing <jats:italic>δ</jats:italic>-phase FAPbI<jats:sub>3</jats:sub>. Whereas, replacing MACl with CsCl could effectively solve this issue. Our founding shows that there is a great need to develop a non-MACl FAPbI<jats:sub>3</jats:sub> perovskite precursor solution for cost-effective preparation of pero-SCs.</jats:p>

<jats:p>Enormous progresses to understand the jamming transition have been driven via simulating purely repulsive particles which were somehow idealized in the past two decades. While the attractive systems are both theoretical and practical compared with repulsive systems. By studying the statistics of rigid clusters, we find that the critical packing fraction <jats:italic>ϕ</jats:italic> <jats:sub>c</jats:sub> varies linearly with attraction <jats:italic>μ</jats:italic> for different system sizes when the range of attraction is short. While for systems with long-range attractions, however, the slope of <jats:italic>ϕ</jats:italic> <jats:sub>c</jats:sub> appears significantly different, which means that there are two distinct jamming scenarios. In this paper, we focus our main attention on short-range attractions scenario and define a new quantity named “short-range attraction susceptibility” <jats:italic>χ</jats:italic> <jats:sub>p</jats:sub>, which describes the degree of response of the probability of finding jammed states <jats:italic>p</jats:italic> <jats:sub>j</jats:sub> to short-range attraction strength <jats:italic>μ</jats:italic>. Our central results are that <jats:italic>χ</jats:italic> <jats:sub>p</jats:sub> diverges in the thermodynamic limit as <jats:inline-formula> <jats:tex-math> <?CDATA ${\chi }_{{\rm{p}}}\propto |\phi -{\phi }_{{\rm{c}}}^{\infty }{|}^{-{\gamma }_{{\rm{p}}}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msub> <mml:mi>χ</mml:mi> <mml:mi mathvariant="normal">p</mml:mi> </mml:msub> <mml:mo>∝</mml:mo> <mml:mo>|</mml:mo> <mml:mi>ϕ</mml:mi> <mml:mo>−</mml:mo> <mml:msubsup> <mml:mi>ϕ</mml:mi> <mml:mi mathvariant="normal">c</mml:mi> <mml:mi>∞</mml:mi> </mml:msubsup> <mml:msup> <mml:mo>|</mml:mo> <mml:mrow> <mml:mo>−</mml:mo> <mml:msub> <mml:mi>γ</mml:mi> <mml:mi mathvariant="normal">p</mml:mi> </mml:msub> </mml:mrow> </mml:msup> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_30_6_066101_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>, where <jats:inline-formula> <jats:tex-math> <?CDATA ${\phi }_{{\rm{c}}}^{\infty }$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msubsup> <mml:mi>ϕ</mml:mi> <mml:mi mathvariant="normal">c</mml:mi> <mml:mi>∞</mml:mi> </mml:msubsup> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_30_6_066101_ieqn2.gif" xlink:type="simple" /> </jats:inline-formula> is the packing fraction at the jamming transition for the infinite system in the absence of attraction. <jats:italic>χ</jats:italic> <jats:sub>p</jats:sub> obeys scaling collapse with a scaling function in both two and three dimensions, illuminating that the jamming transition can be considered as a phase transition as proposed in previous work.</jats:p>

<jats:p>Pressure has an important effect on chemical bonds and their chemical properties. The atypical compounds NaCl<jats:sub>3</jats:sub> and CsF<jats:sub>3</jats:sub> are predicted to be stable at high pressure and show unique physical and chemical properties. By using <jats:italic>ab initio</jats:italic> random structure searching and density functional theory calculations, we predicted multiple thermodynamically stable atypical compounds, which are RbF<jats:sub>2</jats:sub>, RbF<jats:sub>3</jats:sub>, RbF<jats:sub>4</jats:sub>, and RbF<jats:sub>5</jats:sub> in the pressure range of 0–300 GPa. In these stable compounds, homonuclear bondings of F<jats:sub>3</jats:sub>, F<jats:sub>4</jats:sub>, and F<jats:sub>5</jats:sub> species are easily formed. The electron structure calculation showed that except for <jats:italic>Fd-</jats:italic>3<jats:italic>m</jats:italic> phase of RbF<jats:sub>2</jats:sub>, these stable compounds are insulators and F 5p orbitals play an important role in the Fermi level. It is interesting that the compounds RbF<jats:sub>5</jats:sub> could be stable at nearly ambient pressure and 0 K which will stimulate experimental studies in the future.</jats:p>

<jats:p>Dynamics of hydrogen doped Cu<jats:sub>50</jats:sub>Zr<jats:sub>50</jats:sub> glass-forming liquids are investigated by using the newly developed modified embedded atomic method (MEAM) potential based on molecular dynamics simulations. We find that the doping of hydrogen atoms slows down the relaxation dynamics, reduces the fragility of supercooled melts, and promotes the occurrence of glass transitions. The dynamic slowdown is suggested to be closely related to the effect of hydrogen atoms on locally ordered structure of melts. With increasing concentration of hydrogen, the five-fold symmetry associated with Cu- and Zr-centered polyhedrons is lowered, on the other hand, the local order featuring metal hydrides is enhanced. The latter dominates the dynamic behaviors of glass-forming liquids, especially for Zr atoms, and results in the dynamic slowdown.</jats:p>

<jats:p>It is reported that SnSe<jats:sub>2</jats:sub> consisting of the same elements as SnSe, is a new promising thermoelectric material with advantageous layered structure. In this work, the thermoelectric performance of polycrystalline SnSe<jats:sub>2</jats:sub> is improved through introducing SnSe phase and electron doping (Cl doped in Se sites). The anisotropic transport properties of SnSe<jats:sub>2</jats:sub> are investigated. A great reduction of the thermal conductivity is achieved in SnSe<jats:sub>2</jats:sub> through introducing SnSe phase, which mainly results from the strong SnSe<jats:sub>2</jats:sub>–SnSe inter-phase scattering. Then the carrier concentration is optimized via Cl doping, leading to a great enhancement of the electrical transport properties, thus an extraordinary power factor of ∼5.12 μW⋅cm<jats:sup>−1</jats:sup>⋅K<jats:sup>−2</jats:sup> is achieved along the direction parallel to the spark plasma sintering (SPS) pressure direction (∥ <jats:italic>P</jats:italic>). Through the comprehensive consideration on the anisotropic thermoelectric transport properties, an enhanced figure of merit <jats:italic>ZT</jats:italic> is attained and reaches to ∼ 0.6 at 773 K in SnSe<jats:sub>2</jats:sub>-2% SnSe after 5% Cl doping along the ∥ <jats:italic>P</jats:italic> direction, which is much higher than ∼ 0.13 and ∼ 0.09 obtained in SnSe<jats:sub>2</jats:sub>-2% SnSe and pristine SnSe<jats:sub>2</jats:sub> samples, respectively.</jats:p>

<jats:p>We synthesized and investigated the boron-doped and boron/nitrogen co-doped large single-crystal diamonds grown under high pressure and high temperature (HPHT) conditions (5.9 GPa and 1290 °C). The optical and electrical properties and surface characterization of the synthetic diamonds were observed and studied. Incorporation of nitrogen significantly changed the growth trace on surface of boron-containing diamonds. X-ray photoelectron spectroscopy (XPS) measurements showed good evident that nitrogen atoms successfully incorporate into the boron-rich diamond lattice and bond with carbon atoms. Raman spectra showed differences on the as-grown surfaces and interior between boron-doped and boron/nitrogen co-doped diamonds. Fourier transform infrared spectroscopy (FTIR) measurements indicated that the nitrogen incorporation significantly decreases the boron acceptor concentration in diamonds. Hall measurements at room temperature showed that the carriers concentration of the co-doped diamonds decreases, and the mobility increases obviously . The highest hole mobility of sample BNDD-1 reached 980 cm<jats:sup>2</jats:sup>⋅V<jats:sup>−1</jats:sup>⋅s<jats:sup>−1</jats:sup>, possible reasons were discussed in the paper.</jats:p>

<jats:p>The high-purity single-photon source plays an important role in the field of quantum information. Usually, it is generated through spontaneous parametric down-conversion process. In this paper, we investigate and summarize a few approaches on obtaining single-photon sources with a high purity using either PPKTP or PPLN nonlinear crystals. Moreover, we present improved schemes to increase the purity based on existing work, corresponding applicable conditions and procedures are discussed and analyzed. Besides, we carry out numerical simulations and show that nearly perfect purity can be reached even without using any filters. Therefore, this work might provide valuable references for the generation and application of high purity single-photon sources.</jats:p>

<jats:p>The multi-reference configuration interaction method plus Davidson correction (MRCI+Q) are adopted to study the low-lying states of SH with consideration of scalar relativistic effect, core-valence (CV) electron correlation, and spin–orbit coupling (SOC) effect. The SOC effect on the low-lying states is considered by utilizing the full Breit–Pauli operator. The potential energy curves (PECs) of 10 Λ–S states and 18 Ω states are calculated. The dipole moments of 10 Λ–S states are calculated, and the variation along the internuclear distance is explained by the electronic configurations. With the help of calculated SO matrix elements, the possible predissociation channels of A<jats:sup>2</jats:sup>Σ<jats:sup>+</jats:sup>, c<jats:sup>4</jats:sup>Σ<jats:sup>−</jats:sup> and F<jats:sup>2</jats:sup>Σ<jats:sup>−</jats:sup> are discussed. The Franck–Condon factors of A<jats:sup>2</jats:sup>Σ<jats:sup>+</jats:sup>–X<jats:sup>2</jats:sup>Π, F<jats:sup>2</jats:sup>Σ<jats:sup>−</jats:sup>–X<jats:sup>2</jats:sup>Π and E<jats:sup>2</jats:sup>Σ<jats:sup>+</jats:sup>–X<jats:sup>2</jats:sup>Π transitions are determined, and the radiative lifetimes of A<jats:sup>2</jats:sup>Σ<jats:sup>+</jats:sup> and F<jats:sup>2</jats:sup>Σ<jats:sup>−</jats:sup> states are evaluated, which are in good agreement with previous experimental results.</jats:p>