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TSN has become the most popular technique in modern safety-critical automotive and industrial automation networks by providing deterministic transmission policies. However, the data of TSN messages may be affected by transient faults. IEEE 802.1CB, a reliability standard in TSN, protects against such faults by providing disjoint redundant routes for each stream. However, the unique assumption may present a new challenge, i.e., an inadequate number of redundant routes that may negatively impact stream scheduling. This article presents an offline fault-tolerant TSN scheduling approach that considers such impacts for real-time streams (such as time-trigger (TT) and audio video bridging (AVB) streams). Specifically, we intend to calculate the minimum upper bound number of disjoint routes required for each stream to meet the reliability requirements, subsequently enhancing the network’s schedulability. We also propose a service degradation function for AVB streams when the network is under heavy load caused by redundant transmissions of TT streams. This function will maintain schedulability and reliability for AVB streams. Experiments with small- and large-scale synthetic networks show the efficiency.

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One-pot oxo-amination of unactivated cyclopropanes with safe, green dioxygen as an oxidant and low-cost amines as nitrogen sources has generated interest since this can directly result in uniform β-located difunctional units. Formation of the three-electron cation radical followed by the nucleophilic attack of amines to open the strained ring of cyclopropanes catalyzed by classic noble-complex photocatalysts was a promising strategy. However, this ring-opening pathway could not maintain the entire second-order nucleophilic substitution (SN2) conversion, which generally led to unsatisfactory enantioselectivity (enantiomeric excess (ee) value ∼60%). Here, we demonstrate that for such a one-step oxo-amination of cyclopropanes with benign dioxygen and pyrazoles, a highly uniform inversion of configuration could be first accomplished through a TiO2photocatalyst. This strategy features low-cost, semiheterogeneous photocatalysis and environmentally friendly reaction conditions, without using any sacrificial reagent or additive. Importantly, our protocol not only provides a relatively broad substrate scope tolerant to a certain range of substituted cyclopropanes and pyrazoles, resulting in various β-amino ketone products (∼50 examples) with excellent conversions and yields, but also retains excellent enantioselectivity (ee value ∼99%). A concerted SN2 ring opening raised from an oxetane cation intermediate rather than a conventional three-electron cation radical prior to attaching to dioxygen was proposed.

Two novel zinc-based metal–organic frameworks were constructed by employing tetraphenylethylene-derived tetracarboxylate/octacarboxylate ligands and a tetrapyridine linker, featuring a 3D porous framework. The two compounds display highly emissive green and blue-green luminescence, which may find uses in multichip LEDs.

Because of their high ionic conductivity, utilizing gel polymer electrolytes (GPEs) is thought to be an effective way to accomplish high-energy-density batteries. Nevertheless, most GPEs have poor adaptability to Ni-rich cathodes to alleviate the problem of inevitable rapid capacity decay during cycling. Therefore, to match LiNi0.8Co0.1Mn0.1O2(NCM811), we applied pentaerythritol tetraacrylate (PETEA) monomers to polymerize in situ in a polyacrylonitrile (PAN) membrane to obtain GPEs (PETEA-TCGG-PAN). The impedance variations and key groups during the in situ polymerization of PETEA-TCGG-PAN are investigated in detail. PETEA-TCGG-PAN with a high lithium-ion transference number (0.77) exhibits an electrochemical decomposition voltage of 5.15 V. Noticeably, the NCM811|PETEA-TCGG-PAN|Li battery can cycle at 2Cfor 120 cycles with a capacity retention rate of 89%. Even at 6C, the discharge specific capacity is able to reach 101.47 mAh g–1. The combination of LiF and Li2CO3at the CEI interface is the reason for the improved rate performance. Moreover, when commercialized LFP is used as the cathode, the battery can also cycle stably for 150 cycles at 0.5C. PETEA and PAN can together foster the transportation of Li+with the construction of a fast ion transport channel, making a contribution to stable charge–discharge of the above batteries. This study provides an innovative design philosophy for designing in situ GPEs in high-energy-density lithium metal batteries.

Adsorptive separation of alkane isomers, especially the efficient separation of mono- and dibranched alkanes, remains challenging in the petrochemical industry. We report here the discrimination of alkane isomers through a thermodynamically driven mechanism by a highly stable calcium-based metal–organic framework. This newly developed 3D structure is built on a tetracarboxylate linker, featuring 1D channels with optimal pore dimensions to discriminate alkane isomers.

In this study, the chemical structure characteristics and reactivity features of three thermally altered coals with different ranks were analyzed by combining molecular modeling and molecular simulation methods to reveal and predict their chemical behaviors and properties. First, 2D molecular models of the three thermally altered coals were constructed based on X-ray photoelectron spectroscopy (XPS), solid-state 13C nuclear magnetic resonance spectroscopy (13C NMR), high-resolution transmission electron microscopy (HRTEM), and ultimate analysis data. 2D molecular models of the three thermally altered coals show different structural characteristics. 3D molecular models of the three thermally altered coals and their potential energy distributions were obtained by geometry optimization and anneal dynamics simulations. For exploring the reactivity of the three thermally altered coals with different ranks, the frontier molecular orbitals and Mulliken bond orders of the three molecular models were calculated based on quantum chemistry calculations. The frontier orbital (HOMO and LUMO) analysis results indicated that compared with the other two thermally altered coals, the thermally altered coal with Roof 8.32% had higher reactivity in electrophilic or nucleophilic reactions. The bond order results provided detailed information on the active sites of the three thermally altered coal molecules, thereby predicting the thermal behaviors of the three thermally altered coals. These works can provide a theoretical basis for the industrial utilization of thermally altered coal. Meanwhile, these three models will be used in the future to study the combustion, pyrolysis, and graphitization mechanisms of thermally altered coals by reactive molecular dynamics methods.

The separation of alkanes with different degrees of branching, particularly mono- and dibranched isomers, represents a challenging yet important industrial process for the production of premium gasoline blending components with high octane number. We report here the separation of linear/monobranched and dibranched alkanes through complete molecular sieving by a robust aluminum-based MOF material, Al-bttotb (H3bttotb = 4,4′,4″-(benzene-1,3,5-triyltris(oxy))tribenzoicacid). Single- and multicomponent adsorption experiments reveal that the material adsorbs linear and monobranched alkanes, but fully excludes their dibranched isomers. Adsorption sites of alkanes within the MOF channels have been identified by single-crystal X-ray diffraction studies, and the adsorption mechanism was explored through computational calculations and modeling. The highly selective adsorption of the MOF should be attributed to its optimal pore dimensions.

Fluorocarbons and chlorocarbons are common volatile organic compounds that pose serious risk to the environment and human health and therefore need to be effectively captured. Herein, we report a series of highly fluorinated metal–organic frameworks with high porosity (Brunauer–Emmett–Teller surface area ∼3000 m2/g) and stability. They show exceptionally high capacity and good recyclability toward the adsorption of fluorocarbons and chlorocarbons.

Over the last few decades, the construction industry has witnessed a growing utilization of aluminum alloys, primarily due to their beneficial characteristics. This trend has sparked numerous research endeavors seeking a more comprehensive understanding of the structural behavior of these alloys, as well as the development of accurate and dependable design principles. This paper aims to provide an all-encompassing review of the existing body of research in this field, delving into the experimental, numerical, and analytical investigations conducted on structural aluminum alloys. The scope of this review encompasses studies that focus on the mechanical properties of aluminum alloys when subjected to monotonic, cyclic, and thermal loading conditions. Additionally, a significant amount of attention is dedicated to examining the structural performance and design considerations pertaining to aluminum columns, beams, and plates, incorporating both experimental and numerical approaches. Furthermore, the performance of connections and composite aluminum-concrete members is thoroughly discussed. The assessment of the applicability of international design specifications to structural aluminum alloys is also addressed in this paper. Throughout the review process, various gaps in our current knowledge are identified, and recommendations for future research endeavors aimed at bridging these gaps are proposed.

Two ultramicroporous metal–organic frameworks, Zn(ox)0.5(trz) and Zn(ox)0.5(atrz) (ox = oxalate, trz = triazolate, and atrz = 3-aminotriazolate), have been synthesized and tested for the adsorptive separation of Xe and Kr. We demonstrate that the Xe/Kr adsorption selectivity relates to the pore size as well as the structure flexibility of the adsorbents.

Gel polymer electrolytes (GPEs) are promising alternatives to liquid electrolytes applied in high-energy-density batteries. Here superior SiO2nanofiber composite gel polymer electrolytes (SNCGPEs) are developed via in-situionic ring-opening polymerization of 1,3-dioxolane (DOL) monomers in SiO2nanofiber membrane (PDOL-SiO2) for lithium metal batteries. The oxygen atoms of PDOL together with Si-O of SiO2construct a more efficient channel for Li+migration. Consequently, the lithium ion transference number (tLi+) and ionic conductivity (σ) at 30 °C of PDOL-SiO2are 0.80 and 1.68 × 10−4S/cm separately. PDOL-SiO2manifests the electrochemical decomposition potentials of 4.90 V. At 0.5 mA/cm2, Li|PDOL-SiO2|Li cell shows a steady cycling performance for nearly 1400 h. LFP|PDOL-SiO2|Li battery can steadily cycle at 0.5 C with a capacity retention rate of 89% after 200 cycles. While cycling at 2 C, the capacity retention rate can maintain at 78% after 300 cycles. This contribution provides a innovative strategy for accelerating Li+transportation viadesigning PDOL molecular chains throughout the SiO2nanofiber framework, which is crucial for high-energy-density LMBs.

Dissolvable, size- and shape-controlled ruthenium dioxide nanoparticles are successfully achieved through a two-phase route. The influence of reaction time, temperature, and monomer concentration and the nature of capping agents on the morphologies of nanoparticles are studied through transmission electron microscopy (TEM). A possible mechanism for the formation and growth of nanoparticles is also involved. X-ray powder diffraction (XRD) confirms the amorphous structure for as-prepared ruthenium dioxide nanoparticles. Samples are immobilized by simple dip-coating on a current collector, and the cyclic voltammetry measurement is utilized to investigate their electrochemical properties. The specific capacitance of one sample can reach as high as 840 F g −1, which reveals the promising application potential to electrochemical capacitors.

Nanocomposites based on atactic polypropylene (aPP) and multiwall carbon nanotubes were prepared by melt blending at 80°C with a Barabender mixer. The morphology, thermal stability, and dynamic mechanical properties of the obtained composites were studied subsequently. SEM observations indicate that the nanotubes are well dispersed in the aPP matrix. Each nanotube is covered by a layer of aPP molecules. Thermal stability of the aPP in nitrogen is found to be enhanced significantly by the addition of nanotubes. Peak temperature of the DTG curve for the nanocomposite with 5 wt % nanotube loading shows about 70°C higher than that of pure aPP. Dynamic mechanical properties of aPP are also influenced by nanotubes, as shown by the increase in the storage modulus as well as significantly broadened loss tanδ peak. These effects of nanotubes on the thermal stability and mechanical properties of aPP are explained by the adsorption effect of the aPP molecules on the nanotube surfaces in this study. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1087–1091, 2005

Block-based programming (BBP) environments have become increasingly commonplace computer science education. Despite a rapidly expanding ecosystem of BBP environments, text-based languages remain the dominant programming paradigm, motivating the transition from BBP to text-based programming (TBP). Support students in transitioning from BBP to TBP is an important and open design question. This work identifies 101 unique BBP environments, analyzes the 46 of them and identifies different design approaches used to support the transition to TBP. The contribution of this work is to provide a snapshot of the current state of BBP environments and how they support learners in transitioning to TBP.

High-quality CdSe quantum dots have been synthesized through an organometallic method with cadmium methoxide as a cadmium precursor. Without any size sorting, the FWHM (full width at half-maximum) in PL spectra almost for all CdSe samples is less than 30 nm and only 22 nm from the best sample. The emission peaks with different particle size in toluene can be tuned from 478 to 654 nm corresponding to a color change from blue-green to red.

Zincblende Cu2SnS3nanocrystals are synthesized from mixtures of CuCl, SnCl2, and sulfur in oleylamine (240 °C, 1 h).