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Carbon hollow sphere encapsulated Ni3Se4 (Ni3Se4@CHS) nanocrystals are prepared using the Ni-soc-MOF by pyrolysis and further selenization.

Here, a tetrakaidecahedron-shaped Cu four-core supramolecule was designed to overcome the defects of supramolecules for lithium-ion batteries. With multiple metal centers, conductive ligands and abundant hydrogen bonds, this novel electrode shows excellent rate capability (459.4 mA h g

Theoretical calculations unveil the charge redistribution over abundant interfaces and the enhanced electronic states of Ru/RuS2 heterostructure. The resulting surface electron-deficient Ru sites display optimized adsorption behavior toward diverse reaction intermediates, thereby reducing the thermodynamic energy barriers. Experimentally, for the first time the laminar Ru/RuS2 heterostructure is rationally engineered by virtue of the synchronous reduction and sulfurization under eutectic salt system. Impressively, it exhibits extremely high catalytic activity for both OER (201 mV @ 10 mA cm-2 ) and HER (45 mV @ 10 mA cm-2 ) in acidic media due to favorable kinetics and excellent specific activity, consequently leading to a terrific performance in acidic overall water splitting devices (1.501 V @ 10 mA cm-2 ). The in-depth insight into the internal activity origin of interfacial effect could offer precise guidance for the rational establishment of hybrid interfaces.

The middle and lower reaches of Hanjiang River Basin (MLHB), areas that have an important ecological function in China, have experienced great changes in the vegetation ecosystem driven by natural environmental change and human activity. Here, we explored the spatio-temporal dynamics of fractional vegetation coverage (FVC) and quantitatively analyzed its driving factors to advance current understanding of how the ecological environment has changed. Specifically, we used the dimidiate pixel model to calculate the FVC of the MLHB from 2001 to 2018 based on Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) data. We then used Theil-Sen median slope (Sen's slope) and coefficient of variation (CV) to explore spatial and temporal variations, as well as characteristics in fluctuations. Finally, we utilized a geographical detector model (with spatial scale effects and spatial data discretization tests) to quantify the influence of the detected natural and human factors. Results showed that average annual FVC was 0.30-0.75 for ~90% of the study area over the 19-year study period with a heterogeneous spatial distribution. FVC variation trend displayed stability and improvement. Areas with higher FVC displayed greater stability. All 10 detected natural and anthropogenic factors were responsible for changes in FVC. The primary factors causing FVC to change were precipitation (in 2001) and slope (in 2018), followed by landform type, distance to water, and nighttime light (NTL) (in 2018). Precipitation and slope consistently displayed the largest interaction across all years. The interaction between human and topographical factors had gradually increasing significance on changes in FVC over the research period. The range and type of factors suitable for promoting vegetation growth were detected in the study area. Results of this study can provide a scientific basis for developing effective strategies for local vegetation protection, restoration, and land resource management.

P2-type Na2/3Ni1/3Mn2/3O2 (P2-NaNM) is a promising cathode material for practical applications in Na-ion batteries due to its high capacity. However, the rearrangement of Na+/vacancy order and cathodic charge order across the Na extraction/intercalation and structural rearrangements of P2-NaNM at high voltages result in rapid capacity fading and insufficient rate capability. Here, a combined structural modulation strategy was presented to solve these challenges via reducing the Na layers spacing through substituting Na sites by Mg ions while simultaneously stabilizing the transition metal (TM) layers through Mg/Ti co-doping. Benefited from the symbiotic effect, P2-NaNM exhibits a significantly enhanced cycling stability and rate capability in the voltage range of 3.0–4.4 ​V. We further revealed that Mn remains Mn4+ while Ni2+ becomes Ni3+ at the surface of Mg/Ti co-substituted P2-NaNM upon charge/discharge process.

Federated learning (FL) aims to protect data privacy by enabling clients to build machine learning models collaboratively without sharing their private data. Recent works demonstrate that information exchanged during FL is subject to gradient-based privacy attacks and, consequently, a variety of privacy-preserving methods have been adopted to thwart such attacks. However, these defensive methods either introduce orders of magnitudes more computational and communication overheads (e.g., with homomorphic encryption) or incur substantial model performance losses in terms of prediction accuracy (e.g., with differential privacy). In this work, we propose $\textsc{FedCG}$, a novel federated learning method that leverages conditional generative adversarial networks to achieve high-level privacy protection while still maintaining competitive model performance. $\textsc{FedCG}$ decomposes each client's local network into a private extractor and a public classifier and keeps the extractor local to protect privacy. Instead of exposing extractors, $\textsc{FedCG}$ shares clients' generators with the server for aggregating clients' shared knowledge aiming to enhance the performance of each client's local networks. Extensive experiments demonstrate that $\textsc{FedCG}$ can achieve competitive model performance compared with FL baselines, and privacy analysis shows that $\textsc{FedCG}$ has a high-level privacy-preserving capability.

C22H25NO5, monoclinic, P21/c (no. 14), a = 15.7241(13) Å, b = 7.0223(5) Å, c = 18.4613(14) Å, β = 100.329(4)°, V = 2005.4(3) Å3, Z = 4, R gt (F) = 0.0495, wR ref (F 2) = 0.1564, T = 296(2) K.

Na2Zn2TeO6 is a potential sodium solid electrolyte of all-solid-state sodium-ion batteries. In this work, Na+ ion conductivity and electrochemical performance of layered Ca-doped Na2Zn2-xCaxTeO6 (x = 0–0.05) (NZTO-Cx) electrolytes have been investigated. The highest conductivity has been achieved 7.54 × 10−4 S cm−1 in NZTO-Cx at x = 0.02, at room temperature due to grain-boundary modification and interlayer-interface elimination. Meanwhile, chemical stability with metallic Na anode and electrochemical window of NZTO-Cx are improved by Ca doping. Furthermore, the cycle stability of Na3V2(PO4)3/NZTO-Cx/Na solid-state batteries have been successfully increased by Ca doping. These advantages highly demonstrate good potential application prospect of NZTO-Cx in all-solid-state sodium-ion batteries.

Ischemic stroke (IS) is a major cause of mortality and disability worldwide. However, the pathogenesis of IS remains unknown, and methods for early prediction and diagnosis of IS are lacking. Metabolomics can be applied to biomarker discovery and mechanism exploration of IS by exploring metabolic alterations. In this review, 62 IS metabolomics studies in the murine model published from January 2006 to December 2020 in the PubMed and Web of Science databases were systematically reviewed. Twenty metabolites (e.g., lysine, phenylalanine, methionine, tryptophan, leucine, lactate, serine, N-acetyl-aspartic acid, and glutathione) were reported consistently in more than two-third murine studies. The disturbance of metabolic pathways, such as arginine biosynthesis; alanine, aspartate and glutamate metabolism; aminoacyl-tRNA biosynthesis; and citrate cycle, may be implicated in the development of IS by influencing the biological processes such as energy failure, oxidative stress, apoptosis, and glutamate toxicity. The transient middle cerebral artery occlusion model and permanent middle cerebral artery occlusion model exhibit both common and distinct metabolic patterns. Furthermore, five metabolites (proline, serine, LysoPC (16:0), uric acid, glutamate) in the blood sample and 7 metabolic pathways (e.g., alanine, aspartate, and glutamate metabolism) are shared in animal and clinical studies. The potential biomarkers and related pathways of IS in the murine model may facilitate the biomarker discovery for early diagnosis of IS and the development of novel therapeutic targets.

We present a novel privacy-preserving federated adversarial domain adaptation approach ($\textbf{PrADA}$) to address an under-studied but practical cross-silo federated domain adaptation problem, in which the party of the target domain is insufficient in both samples and features. We address the lack-of-feature issue by extending the feature space through vertical federated learning with a feature-rich party and tackle the sample-scarce issue by performing adversarial domain adaptation from the sample-rich source party to the target party. In this work, we focus on financial applications where interpretability is critical. However, existing adversarial domain adaptation methods typically apply a single feature extractor to learn feature representations that are low-interpretable with respect to the target task. To improve interpretability, we exploit domain expertise to split the feature space into multiple groups that each holds relevant features, and we learn a semantically meaningful high-order feature from each feature group. In addition, we apply a feature extractor (along with a domain discriminator) for each feature group to enable a fine-grained domain adaptation. We design a secure protocol that enables performing the PrADA in a secure and efficient manner. We evaluate our approach on two tabular datasets. Experiments demonstrate both the effectiveness and practicality of our approach., Comment: Published in IEEE Transactions on Big Data

The instinct scaling relations between the adsorption energies of key intermediates during OER lead to large overpotential for water/seawater splitting. Herein, we develop a new strategy to fabricate amorphous nickel-iron phosphides (NiFeP) with controllable morphologies as high-performance catalysts for overall seawater splitting. The ligand effect of P tunes the electronic states of the oxidized NiFe sites, thus breaks the scaling relations for OER and reduce the adsorption energy gap between HO* and HOO* from 3.08 eV to 2.62 eV. The NiFeP nanostructures exhibit extraordinarily low overpotentials of 129 mV for OER and 126 mV for HER at 100 mA cm−2 in simulated alkaline seawater, which outperform the best reported electrocatalysts. They could also be operated at 1.57 V with 100 mA cm−2 in a two-electrode electrolyzer and work for more than 500 h. Our work may provide a universal guidance for the design of highly active seawater splitting electrocatalysts.

[Co(C11H11O2N2)2(H2O)2], monoclinic, P 2 1 / c $P{2}_{1}/c$ (no. 14), a = 8.7117(5) Å, b = 8.7935(5) Å, c = 15.0791(9) Å, β = 103.557(1)°, V = 1122.97(11) Å3, Z = 2, R gt (F) = 0.0271, wR ref (F 2) = 0.0725, T = 296(2) K.

A novel solid sodium-ion conductor, Na2Mg2TeO6 (NMTO) with a P2-type honeycomb-layered structure, has been synthesized for the first time by a simple solid-state synthetic route. The conductor of NMTO exhibits high conductivity of 2.3 × 10-4 S cm-1 at room temperature (RT) and a large electrochemical window of ∼4.2 V (versus Na+/Na). The conductor is remarkably stable, both in the ambient environment and within its metallic Na anode. This facile sodium-ion conductor displays potential for use in all-solid-state sodium-ion batteries (SS-SIBs).

Here, a P2-type layered Na2 Zn2 TeO6 (NZTO) is reported with a high Na+ ion conductivity ≈0.6×10-3 S cm-1 at room temperature (RT), which is comparable to the currently best Na1+n Zr2 Sin P3-n O12 NASICON structure. As small amounts of Ga3+ substitutes for Zn2+ , more Na+ vacancies are introduced in the interlayer gaps, which greatly reduces strong Na+ -Na+ coulomb interactions. Ga-substituted NZTO exhibits a superionic conductivity of ≈1.1×10-3 S cm-1 at RT, and excellent phase and electrochemical stability. All solid-state batteries have been successfully assembled with a capacity of ≈70 mAh g-1 over 10 cycles with a rate of 0.2 C at 80 °C. 23 Na nuclear magnetic resonance (NMR) studies on powder samples show intra-grain (bulk) diffusion coefficients DNMR on the order of 12.35×10-12 m2 s-1 at 65 °C that corresponds to a conductivity σNMR of 8.16×10-3 S cm-1 , assuming the Nernst-Einstein equation, which thus suggests a new perspective of fast Na+ ion conductor for advanced sodium ion batteries.

Sodium iron hexacyanoferrate (Fe-HCF) has been proposed as a promising cathode material for sodium-ion batteries (SIBs) because of its desirable advantages, including high theoretical capacity (∼170 mAh g–1), eco-friendliness, and low cost of worldwide rich sodium and iron resources. Nonetheless, its application faces a number of obstacles due to poor electronic conductivity and structural instability. In this work, Fe-HCF nanospheres (NSs) were first synthesized and fabricated by an in situ graphene rolls (GRs) wrapping method, forming a 1D tubular hierarchical structure of Fe-HCF NSs@GRs. GRs not only provide fast electronic conduction path for Fe-HCF NSs but also effectively prevent organic electrolyte from reaching active materials and inhibit the occurrence of side reactions. The Fe-HCF NSs@GRs composite has been used as a binder-free cathode with a capacity of ∼110 mAh g–1 at a current density of 150 mA g–1 (∼1C), the capacity retention of ∼90% after 500 cycles. Moreover, the Fe-HCF NSs@GRs cathode ...

As an anode material for sodium-ion batteries (SIBs), hard carbon (HC) presents high specific capacity and favorable cycling performance. However, high cost and low initial Coulombic efficiency (ICE) of HC seriously limit its future commercialization for SIBs. A typical biowaste, mangosteen shell was selected as a precursor to prepare low-cost and high-performance HC via a facile one-step carbonization method, and the influence of different heat treatments on the morphologies, microstructures, and electrochemical performances was investigated systematically. The microstructure evolution studied using X-ray diffraction, Raman, Brunauer–Emmett–Teller, and high-resolution transmission electron microscopy, along with electrochemical measurements, reveals the optimal carbonization condition of the mangosteen shell: HC carbonized at 1500 °C for 2 h delivers the highest reversible capacity of ∼330 mA h g–1 at a current density of 20 mA g–1, a capacity retention of ∼98% after 100 cycles, and an ICE of ∼83%. Additionally, the sodium-ion storage behavior of HC is deeply analyzed using galvanostatic intermittent titration and cyclic voltammetry technologies.

Sodium-ion batteries (SIBs) have shown extensive prospects as alternative rechargeable batteries in large-scale energy storage systems, because of the abundance and low cost of sodium. The development of high-performance cathode and anode materials is a big challenge for SIBs. As is well known, TiNb2O7 (TNO) exhibits a high capacity of ∼250 mAh g–1 with excellent capacity retention as a Li-insertion anode for lithium-ion batteries, but it has rarely been discussed as an anode for SIBs. Here, we demonstrate ball-milled TiNb2O7 (BM-TNO) as an SIB anode, which provides an average voltage of ∼0.6 V and a reversible capacity of ∼180 mAh g–1 at a current density of 15 mA g–1, and presents excellent cyclability with 95% capacity retention after 500 cycles at 500 mA g–1. A possible Na storage mechanism in BM-TNO is also proposed.

By reacting with indium nitrate and tetrakis(4-carboxyphenyl)-porphyrin (H4TCPP), a mesoporous indium–porphyrin framework, named JLU-Liu7, which features a rare (4,4)-connected frl net based on 1D inorganic indium rod SBUs, has been constructed. It exhibits high performance for gas adsorption and light hydrocarbon separation.

A novel solid sodium-ion conductor, Na

A novel three-dimensional metal–organic framework, [Cu2I2]0.5[Cu2(CO2)4(C10H7N2)4]0.5·2DMF (JLU-Liu14), has been synthesized under solvothermal conditions, which is constructed by ternary secondary building units (SBUs): classical Cu2(CO2)4 paddle-wheel unit, Cu2I2 dimer unit, and organic SBU. In JLU-Liu14, the pyrimidine groups of 4-PmBC (4-(pyrimidin-5-yl) benzoic acid) ligands coordinated to copper paddle-wheel and Cu2I2 dimer units to form a zigzag chain, and the zigzag chains then connected together by 4-PmBC ligands to generate a three-dimensional framework with (3,4,6)-connected topology. There are two types of channels along the c axis with the dimensions of 14 × 14 A and 5 × 5 A, respectively, in which the big hexagonal channel is surrounded by six small trigonal channels. In addition, JLU-Liu14 displays the interesting ability of the uptake and release of iodine.

Here, a P2-type layered Na

Particle swarm optimization (PSO) algorithm is a random search method based on population evolution. At present, most of the convergence and search stability of the study are using a method of analyzing deterministic systems. Although these studies have achieved fruitful results, but they ignore the randomness of the PSO algorithm which is the most important feature. The complexity and uncertainty of the algorithm is due to the existence of random factors. This paper considers the stochastic factors of the PSO algorithm, from the point of view of stochastic system robust control, a novel PSO algorithm model based on discrete stochastic control system is proposed. Then the robust controllability analysis of the model is carried out, and the robust controllable condition and control law are obtained. Based on this, a new particle swarm optimization algorithm, named particle swarm optimization algorithm based on random robust control is proposed. The simulation results verify the effectiveness of proposed algorithm.

Sodium-ion batteries (SIBs) have shown extensive prospects as alternative rechargeable batteries in large-scale energy storage systems, because of the abundance and low cost of sodium. The development of high-performance cathode and anode materials is a big challenge for SIBs. As is well known, TiNb

A novel data-driven model-free adaptive control (DDMFAC) approach is first proposed by combining the advantages of model-free adaptive control (MFAC) and data-driven optimal iterative learning control (DDOILC), and then its stability and convergence analysis is given to prove algorithm stability and asymptotical convergence of tracking error. Besides, the parameters of presented approach are adaptively adjusted with fuzzy logic to determine the occupied proportions of MFAC and DDOILC according to their different control performances in different control stages. Lastly, the proposed fuzzy DDMFAC (FDDMFAC) approach is applied to the control of particle quality in drug development phase of spray fluidized-bed granulation process (SFBGP), and its control effect is compared with MFAC and DDOILC and their fuzzy forms, in which the parameters of MFAC and DDOILC are adaptively adjusted with fuzzy logic. The effectiveness of the presented FDDMFAC approach is verified by a series of simulations.

A series of supported Ni/TiO 2 catalysts were prepared by incipient wetness impregnation method under different calcination temperatures, and the as-prepared catalysts were characterized by X-ray diffraction (XRD), hydrogen temperature-programmed reduction (H 2 -TPR) and X-ray photoelectron spectroscopy (XPS). The catalytic properties of these Ni/TiO 2 catalysts were investigated in the vapor phase hydrogenation of maleic anhydride (MA) to succinic anhydride (SA). The results showed that the catalytic activity and the selectivity of the Ni/TiO 2 catalysts were strongly affected by the calcination temperature. The catalyst calcined at 1023 K showed a relatively higher SA selectivity of 96% at high MA conversion (96%) under the tested conditions (493 K and 0.2 MPa). The improvement of SA selectivity could be mainly assigned to the presence of suitable metal–support interaction, which can play a role in catalytic property of active nickel species as electron promoter. Besides, the change of surface properties of TiO 2 support with the increasing calcination temperatures, e.g., the decrease of Lewis acid sites, might also have some positive role in reducing the side-products like γ-butyrolacetone (GBL).

Cu/SiO2 catalysts that contain copper phyllosilicate, were successfully prepared using the ammonia-evaporation method. The catalysts were characterized via XRD, ICP, BET, FTIR, TPR, XPS, NH3-TPD and FTIR of Pyridine Adsorption techniques. The results demonstrated that the formation of the copper phyllosilicate species significantly affected the structural properties and caused the CuO nanoparticles to become highly dispersed, and the copper phyllosilicate would provide access to the Lewis acidic Cu+ species. It was found that the catalyst with a 23.7 wt% copper loading exhibited the best ethanol conversion and ethyl acetate selectivity. When compared to a catalyst with the same copper loading which was prepared with the impregnation method, the higher activity and selectivity of catalysts might be ascribed to the homogenous distribution of copper nanoparticles, which was the active site for the dehydrogenation, and the amount of Lewis acidic Cu+ sites active for esterification. The synergetic effect between the Cu0 and Lewis acidic sites was the key factor to achieve direct transformation of ethanol to ethyl acetate.

[In(bpydc)(NO3)(DMA)0.5]·(DMA)(H2O)4.5 (JLU-Liu8), [In(bpydc)(HCOO)H2O]·(DMF)2(H2O)3 (JLU-Liu9) and [In(bpydc)Cl]·(DMF)2(H2O)3 (JLU-Liu10), three novel 3D monoatomic indium–organic frameworks, have been synthesized from the 2,2′-bipyridine-5,5′-dicarboxylic acid (H2bpydc) ligand under solvothermal conditions. These three compounds are constructed from the same ligand, but templated using three different anions (NO3−, HCOO− and Cl−), and they exhibit three different 4-connected ung, crb and cbo network topologies. JLU-Liu8 exhibits two types of single-helical chains with opposite helical directions (left-handed and right-handed), all of the left-handed and right-handed helical chains alternate together. In the structure of JLU-Liu9, there are two types of metal–ligand channels: the smaller square channels with dimensions 3.45 A × 4.03 A and the bigger square channels with dimensions of 11.5 A × 11.5 A. JLU-Liu10 displays an interesting feature of double-helical chains: both helical chains are interconnected with each other by sharing indium ions which entangle one spiral shaft. Furthermore, the role of anions in assisting the formation of distinct structures has been discussed. These three compounds display strong luminescence in the solid state at room temperature.

Pd/Al2O3 catalysts were prepared via colloid deposition and the performance of the catalysts was examined in the selective hydrogenation of maleic anhydride to succinic anhydride. When the reaction was carried on in a batch system with 1,4-dioxane as the solvent (353 K and 1.0 MPa), high conversion of maleic anhydride (>98%) and high selectivity (>99%) for succinic anhydride were observed after 5 h. The as-prepared Pd/Al2O3 catalyst also showed excellent performance in solvent-free system and fixed-bed systems. The maleic anhydride (MA) conversion was greater than 98%, and high selectivity (>99%) for succinic anhydride was obtained after 1600 h in a fixed bed reacter. The results showed that the activity of the Pd/Al2O3 catalysts was excellent due to its high active surface area.

Direct transformation of ethanol to ethyl acetate was investigated on a series of Cu(ZrO2)/SiO2 catalysts. Inductively coupled plasma(ICP), surface area analysis, X-ray diffraction(XRD), H2-temperature programmed reduction(H2-TPR), X-ray photoelectron spectroscopy(XPS), NH3-temperature programmed desorption(NH3-TPD) and Fourier transform-infrared spectroscopy(FTIR) techniques were used to characterize the catalysts. The results reveal that ZrO2 can improve the dispersion of copper species and increase the acidity of the Cu(ZrO2)/SiO2 catalysts. The Cu0 is responsible for ethanol dehydrogenation to acetaldehyde, and both the Lewis acid and Bronsted acid sites were in favor of the selectivity to ethyl acetate. The synergistic effect of Cu0 and an appropriate amount of acidic sites played an important role in the production of ethyl acetate.

Six novel coordination polymers based on a multifunctional ligand, 5,5′-(1,2-ethynyl)bis-1,3-benzenedicarboxylic (H4EBDC), namely, |(C3H7NO)2(H2O)7(C2H5OH)3|[Zn2(C18H6O8)(C10H8N2)2] (1), |(C3H7NO)3(H2O)30(CH3CN)2|[Zn6(C18H6O8)3(C6H12N2O2)2] (2), |(C3H7NO)2(H2O)2(H3O)2|[Cd3(C18H6O8)2] (3), |(C3H7NO)|[Mn(C18H8O8)(C3H7NO)2] (4), |(C3H7NO)2(H2O)(C2H7N)3|[Mn6(C18H7O8)4(H2O)8] (5), and [Mn2(C18H6O8)(C3H7NO)2] (6), have been constructed under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction. In these compounds, the ligand, H4EBDC, exhibits different coordination modes and conformations, constructing various architectures by bridging a variety of metal ions or polynuclear clusters. Compound 1 forms a three-dimensional (3D) FSC network constructed from two-dimensional (2D) layer motifs joined by EBDC4– and 4,4′-bipyridine bridges. Compound 2 possesses an NbO topology by linking Zn2(CO2)4 units with the ligand, coordinated amine molecules fill the pores, while compound 3 ex...

By using 4-(pyrimidin-5-yl) benzoic acid (4-PmBC) as a ligand, a porous metal–organic framework based on unique octa-nuclear copper clusters was constructed, which exhibited highly selective CO2 uptake over N2 and CH4.