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The greedy routing in sensor networks can be classified into two categories,strong greedy routing and weak greedy routing.The weak greedy routing protocol needs geographic location and strong greedy routing needs greedy em-bedding network.In order to solve these problems and minimize operation complexity and energy overhead,a light-weight tree-based network embedding graph（TNEG） was proposed and over the TNEG,a local monotone function was designed and two routing rules were proposed,then two weak greedy routing protocols,TGR and biTGR were de-signed.The simulation shows two protocols achieve good performance on path stretch factor and load balance factor.

Abstract Background The presence of tandem amino acid repeats (AARs) is one of the signatures of eukaryotic proteins. AARs were thought to be frequently involved in bio-molecular interactions. Comprehensive studies that primarily focused on metazoan AARs have suggested that AARs are evolving rapidly and are highly variable among species. However, there is still controversy over causal factors of this inter-species variation. In this work, we attempted to investigate this topic mainly by comparing AARs in orthologous proteins from ten angiosperm genomes. Results Angiosperm AAR content is positively correlated with the GC content of the protein coding sequence. However, based on observations from fungal AARs and insect AARs, we argue that the applicability of this kind of correlation is limited by AAR residue composition and species' life history traits. Angiosperm AARs also tend to be fast evolving and structurally disordered, supporting the results of comprehensive analyses of metazoans. The functions of conserved long AARs are summarized. Finally, we propose that the rapid mRNA decay rate, alternative splicing and tissue specificity are regulatory processes that are associated with angiosperm proteins harboring AARs. Conclusions Our investigation suggests that GC content is a predictor of AAR content in the protein coding sequence under certain conditions. Although angiosperm AARs lack conservation and 3D structure, a fraction of the proteins that contain AARs may be functionally important and are under extensive regulation in plant cells.

2D conductive metal–organic frameworks (2D c‐MOFs) have attracted increasing attention as promising electrode materials for rechargeable batteries due to their designable periodic motifs, large specific surface areas, and prominent electrical conductivity. However, the development of 2D c‐MOF electrode materials with functionality remains a significant challenge because of the limited electroactive ligand motifs available. Herein, a hexahydroxy‐substituted triazacoronene ligand (6OH‐TAC) is deliberately designed and synthesized, which coordinates with Cu2+ ions to form an unprecedented 2D c‐MOF (Cu‐TAC) with functionality sites of efficient lithium storage. The synergistic effect of TAC and CuO4 enables Cu‐TAC as an anode for lithium‐ion batteries with a superior reversible capacity of 772.4 mAh g−1 at 300 mA g−1, remarkable rate performance, and outstanding long‐term cyclability (83% capacity retention at 300 mA g−1 for 600 cycles). These metrics outperform almost all 2D c‐MOF‐based electrodes, shedding light on new opportunities for energy storage devices. [ABSTRACT FROM AUTHOR]

Fluoropolymers and metal halide perovskites (MHPs), as two classes of important piezoelectric materials, suffer from active phases through a facile process and brittleness led poor manufacturability, respectively. Here, TMCM‐CdCl3/PVDF nanocomposites (TMCM = trimethylchloromethyl ammonium, PVDF = polyvinylidene fluoride) are synthesized to overcome the above shortcomings. The abundant hydrogen (H) and chlorine (Cl) sites in TMCM‐CdCl3 can interlock with H and fluorine (F) atoms within PVDF via C─H···Cl and C─H···F interactions. This programming effect augments the dipole alignment and consequently promotes the formation of polar phases within PVDF. The devices made by these nanocomposites exhibit high energy harvesting properties surpassing established MHP/PVDF analogues, and prominent performance in sensing delicate human motions. Moreover, the devices show exceptional capabilities for detecting underwater ultrasound waves. The signal intensity is ≈4 times that of commercial PVDF film devices, and the frequency distortion is only a quarter of that observed in commercial ceramic transducers. This study opens up new possibilities for developing high‐performance piezoelectric nanocomposites and the creation of advanced electromechanical devices. [ABSTRACT FROM AUTHOR]

Chiral hybrid metal halides have emerged as a promising class of piezoelectric materials owing to their ease of synthesis, low acoustic impedance, and solution processibility. However, many known chiral halides crystalize in structures with only shear piezoelectricity which is less facile to be utilized compared with the longitudinal piezoelectricity, largely preventing their practical utility. In addressing this problem, chiral lead‐free S‐MPBiCl5 and R‐MPBiCl5 (MP = 2‐methylpiperazinium) with shear piezoelectricity are synthesized and the thin films orientating along the polarization direction are fabricated. These orientated films, characterized by numerous grains and compact grain boundaries, can effectively facilitate the grain boundary sliding to convert normal stress into shear stress, thus facilely activating the shear piezoelectricity. The resulting devices can accurately identify the position and type of ultrasound sources without the need for a complex acoustic impedance matching layer. Moreover, these devices can successfully sense delicate variations in momentum caused by table tennis balls. The findings open up a new pathway to utilize shear piezoelectricity that is normally considered unuseful of metal halides and other molecular piezoelectrics. [ABSTRACT FROM AUTHOR]

As an important part of die steels, hot-work die steels are mainly used to manufacture molds made of solid metal or high-temperature liquid metal from heating to recrystallization temperature. In view of the requirements for mechanical properties and service life for hot-work die steel, it is conducive to improve the thermal fatigue resistance, wear resistance, and oxidation resistance of hot work die steel. In this review, the main failure modes of hot-work die steel were analyzed. Four traditional methods of strengthening and toughening die steel were summarized, including optimizing alloying elements, electroslag remelting, increasing the forging ratio, and heat treatment process enhancement. A new nano-strengthening method was introduced that aimed to refine the microstructure of hot-work abrasive steel and improve its service performance by adding nanoparticles into molten steel to achieve uniform dispersion. This review provides an overview to improve the service performance and service life of hot work die steel. [ABSTRACT FROM AUTHOR]