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A viable anode of atomic Sb with a super-coordinated O2Sb1N4 structure anchored on N-doped micropore carbon nanosheets (O–Sb–N SA@NC) is developed, demonstrating significantly enhanced performance in both half and full potassium-ion batteries.

Purpose The purpose of this paper is to develop high-performance Au-coated Ag alloy wires (ACAA wires) and demonstrate the effect of Au coating layers on the bonding performance and oxidation resistance for stable and reliable electronic packaging applications. Design/methodology/approach ACAA wire with a diameter of approximately 25 µm and Au layer thickness of approximately 100 nm were prepared by the continuous casting, plating and wire drawing method. The bonding performance of the ACAA wires were studied through bonding on 3,535 chips. The oxidation resistance of ACAA wires and Ag alloy wires (AA wires) were comparatively studied by means of chemical oxidation tests, accelerated life tests and electrochemical tests systematically. Findings ACAA wires could form axi-symmetrical spherical free air balls with controllable diameter of 1.5∼2.5 times of the wire diameter after electric flame-off process. The ball shear strength of ACAA wire was higher than that of AA wires. Most importantly, because of the surface Au coating layer, the oxidation resistance of ACAA wires was much enhanced. Research limitations/implications ACAA wires with different lengths of heat affected zone were not developed in this study, which limited their application with different loop height requirements. Practical implications With higher bonding strength and oxidation resistance, ACAA wires would be a better choice than previous reported AA wire in chip packaging which require high stability and reliability. Originality/value This paper provides a kind of novel ACAA wire, which possess the merits of high bonding strength and reliability, and show great potential in electronic packaging applications.

Constructing 3D skeletons modified with lithiophilic seeds has proven effective in achieving dendrite-free lithium metal anodes. However, these lithiophilic seeds are mostly alloy- or conversion-type materials, and they tend to aggregate and redistribute during cycling, resulting in the failure of regulating Li deposition. Herein, we address this crucial but long-neglected issue by using intercalation-type lithiophilic seeds, which enable antiaggregation owing to their negligible volume expansion and high electrochemical stability against Li. To exemplify this, a 3D carbon-based host is built, in which ultrafine TiO

Carbonaceous materials featuring both ordered graphitic structure and disordered defects hold great promise for high-performance K-ion batteries (KIBs) due to the concurrent advantages of high electronic conductivity, fast and reversible K

Underwater acoustic sensor networks (UASNs) have gradually received attention due to their widespread applications, such as in disaster prevention, environmental monitoring and military activities, and they simultaneously face security challenges. In recent years, trust management mechanisms have become important tools for responding to internal attackers. However, most of the existing trust management mechanisms do not consider the adverse influence of complex underwater environment on node evaluation, and do not deal with the case that normal nodes are misjudged as malicious nodes. To achieve accurate trust evaluation of nodes and reduce the possibility of misjudgment of normal nodes, a redeemable Support Vector Machine-Dempster-Shafer (SVM-DS) fusion-based trust management mechanism (SDFTM) is proposed for UASNs in this paper. First, according to the characteristics of attacks, three kinds of trust evidence are selected: packet-based evidence, data-based evidence and energy-based evidence. Then the support vector machine (SVM) is applied to classify the trust of node from the aspect of each kind of trust evidence, while Dempster-Shafer (DS) evidence theory is used to fuse the different trust classification results of nodes. Second, to deal with cases where a normal node may be misclassified as a malicious node, trust redemption process is carried out based on the historical performance and environmental influence (unreliable acoustic channel, weak link connectivity). Finally, the trust value is calculated and updated. The simulation results prove that the proposed scheme yields satisfactory performance in malicious detection and reduce the possibility of misjudgment of normal nodes.

Hybrid systems have recently attracted increasing attention, which combine the special attributes of each constitute and create interesting functionalities through multiple heterointerface interactions. Here, we design a two-dimensional (2D) hybrid phototransistor utilizing Janus-interface engineering, in which the WSe

Owing to the dramatically enhanced charge-mass transport and abundant electrochemically active sites, transition metal compound electrodes are increasingly attractive for achieving high-performance supercapacitors (SCs). Here, we report the fabrication of nickel foam supported three-dimensional (3D) branched nickel–cobalt phosphides@tri-metal cobalt–nickel-molybdenum phosphides core/shell nanowire heterostructures (denoted as NiCo-P@CoNiMo-P) as high-performance electrode materials for hybrid supercapacitors. The presence of multiple valences of the cations in such NiCo-P@CoNiMo-P enables rich redox reactions and promoted synergy effects. Benefiting from their collective effects, the resulting electrode demonstrates high specific capacity of 1366 C g−1 at 2 A g−1 (2.03 C cm−2 at 2 mA cm−2) and 922 C g−1 at 10 A g−1, as well as good cycling stability (retaining ~ 94% of the initial capacity after 6000 cycles at 15 A g−1). A hybrid SC using the NiCo-P@CoNiMo-P as the positive electrode and N-doped rGOs as the negative electrode exhibits a high energy density of 81.4 Wh kg−1 at a power density of 1213 W kg−1 and a capacity retention of 132% even after 6000 cycles at 10 A g−1. Our findings can facilitate the material design for boosting the performance of transition metal compounds based materials for fast energy storage.

In Underwater Wireless Sensor Networks (UWSNs), data should be transmitted to data centers reliably and efficiently. However, due to the harsh channel conditions, reliable data transmission is a challenge for large-scale UWSNs. Thus, opportunistic routing (OR) protocols with high reliability, strong robustness, low end-to-end delay, and high energy efficiency are widely applied. However, OR in UWSNs is vulnerable to routing attacks. For example, sinkhole attack nodes can attract traffic from surrounding nodes by forging information such as the distance to the sink node. In order to reduce the negative impact of malicious nodes on data transmission, we propose an intrusion detection scheme (IDS) based on the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) clustering algorithm for OR (DOIDS) in this paper. DOIDS is based on small-sample IDS and is suitable for UWSNs with sparse node deployment. In DOIDS, the local monitoring mechanism is adopted. Every node in the network running DOIDS can select the trusted next hop. Firstly, according to the behavior characteristics of common routing attack nodes and unreliable underwater acoustic channel characteristics, DOIDS selected the energy consumption, forwarding, and link quality information of candidate nodes as the detection feature values. Then, the collected feature information is used to detect potential abnormal nodes through the DBSCAN clustering algorithm. Finally, a decision function is defined according to the time decay function to reduce the false detection rate of DOIDS. It makes a final judgment on whether the potential abnormal node is malicious. The simulation results show that the algorithm can effectively improve the detection accuracy rate (3% to 15% for different scenarios) and reduce the false positive rate, respectively.

One environmentally friendly method used to manage Bactrocera dorsalis (Hendel), a key agricultural pest of substantial economic importance, is the sterile insect technique (SIT). Nevertheless, several deficiencies related to this strategy impair the success of the SIT, including the inferior performance of released sterile males compared with wild males, which could be partly solved by the utilization of gut symbionts as probiotic dietary components. In this study, a culture-dependent method was used to isolate and characterize gut-associated bacterial species in adult B. dorsalis genetic sexing strain (GSS) males. In addition, three bacterial isolates from the Enterobacteriaceae family, namely, Enterobacter sp., Morganella morganii, and Moellerella wisconsensis, were used as supplements in larval and adult diets to assess their effects on the life-history traits of irradiated males. Consistent with many previous studies, Enterobacter spp. was shown to be beneficial, with some quality control indices, such as adult size, pupal weight, survival rate under stress and nutritionally rich conditions, and mating competitiveness, being significantly increased, while slight nonsignificant increases in emergence rate and flight ability were observed. Conversely, the M. morganii and M. wisconsensis strains both had negative effects on irradiated male fitness and mating competitiveness. Our results, in combination with those of earlier studies, can contribute to improving the effectiveness of SIT application by enhancing the different aspects of augmentative rearing and biological traits of pests under laboratory rearing conditions.

Low silver Sn-0.3Ag-0.7Cu (SAC0307) composite solder reinforced with graphene nanosheets (GNs) was prepared by powder metallurgy techniques, and the effects of GN content on the melting characteristics, wettability, microhardness and shear strength of the composite solder were investigated. The wettability and microhardness of the composite solder increased significantly, and the initial melting temperature decreased slightly with increasing doping content of GNs, the wettability and microhardness of the composite solder increased significantly, but the initial melting temperature decreased slightly. When the GN content reaches 0.01 wt.%, the wettability angle of the composite solder decreases by ∼ 29%. When the content of GNs reaches 0.09 wt.%, composite solder of microhardness is up to 15.3 HV, approximately 1.12 times larger than that of the un-doped SAC0307 solder. At the same time, it is also found that the shear strength of the composite solder increases with the increase of GN content. When reaching 0.05 wt.%, the shear strength is the highest (24.70 MPa) and then presents a downward trend. In addition, the fracture morphology of microscale solder joints exhibits a typical ductile fracture character to the brittle one with increasing GN content.

Cysteine (Cys) is well-known to be an important biothiol and related to many diseases. However, the in situ trapping of endogenous Cys is still handicapped by a lack of straightforward methods combined with long-wavelength emission and high-performance response. In this work, we described the rational design strategy of cyanine-based near-infrared (NIR) probes for the rapid detection of mitochondrial Cys in living cells and mice. We focus on how to improve the response rate via regulating the electron density of the recognition units in probes. The obtained three probes all displayed remarkable fluorescence enhancement at 780 nm. From screening the obtained probes, it was found that the probe Cy-S-diOMe with electron-donating recognition unit displayed the fastest response rate, the lowest detection limit, and the highest signal-to-noise ratio. More importantly, Cy-S-diOMe was successfully applied to monitor Cys in tumor-bearing mice (within merely 5 min). This paradigm by modulation of the response rate in the cyanine dyes provides a promising methodology for the design of high-performance cyanine-based NIR probes.

The tensile creep properties of line-type Cu/Sn–0.3Ag–0.7Cu(SAC0307)–xNi (x = 0, 0.02, 0.05 and 0.10 wt%)/Cu solder micro-joints were comparatively investigated via dynamic mechanical analysis. The effect of Ni content on the creep behaviour of the solder micro-joints was analysed and discussed. The creep behaviour of the joints at various temperatures and applied stresses was described by a power law. The results showed that the creep lifetime, creep activation energy and creep stress exponent of the Ni-containing solder micro-joints were greater than those of the Ni-free joint. Hence, adding Ni to the SAC0307 solder can enhance the creep resistance of the solder joints. The creep activation energy and the creep stress exponent of the solder micro-joints at 353–398 K and under a tensile stress of 8–15 MPa were 82.44–93.36 kJ/mol and 4.35–4.75, respectively. As the Ni content increased, the creep activation energy and the creep stress exponent first increased and then decreased. The Cu/SAC0307–0.05Ni/Cu solder micro-joint exhibited the strongest creep resistance among the tested joints. The creep deformation mechanisms of all solder micro-joints were mainly controlled by dislocation climbing, and the main creep failure mode was mixed brittle/ductile fracture.

Glucose oxidase (GOD)-based synergistic cancer therapy has aroused great research interest in the context of cancer treatment due to the inherent biocompatibility and biodegradability. However, this emerging therapeutic system still lacks a strategy to predict and regulate the in vivo biocatalytic behavior of GOD in real time to minimize the side effects on normal tissues. Herein, we developed a tumor-specific cascade nanotheranostic system (BNG) that combines GOD-catalyzed oxidative stress and dual-channel fluorescent sensing, significantly improving the synergistic therapeutic efficacy with real-time feedback information. The nanotheranostic system remains completely silent in the blood circulatory system and selectively releases GOD enzymes in the tumor site, with enhanced near-infrared (NIR) fluorescence at 825 nm. Subsequently, GOD catalyzes H2O2 production, triggering cascade reactions with NIR fluorescence at 650 nm as an optical output, along with GSH depletion, enabling synergistic cancer treatment. The designed nanotheranostic system, integrated with tumor-activated cascade reactions and triggering a dual-channel output at each step, represents an insightful paradigm for precise cooperative cancer therapy., Herein, we described the strategy of cascade nanotheranostics for in real-time tracking of GOD release and thus provide the feedback information of biocatalysis cascade process with significantly enhanced in vivo therapeutic efficiency.

Hard carbon materials have been recognized as a promising family of anode materials for potassium ion batteries (PIBs), but their practical application is severely hindered due to the inferior initial coulombic efficiency (ICE) and low capacity. Herein, we report our findings in simultaneously improved potassium storage capacity and ICE through the design of nano-size and porous structure and the appropriate selection of electrolytes. Benefiting from the high specific surface area, stable electrode|electrolyte interface, and fast potassium ion and electron transfer, the optimized electrode exhibits a high ICE of up to 68.2% and an outstanding reversible capacity of 232.6 mA h g-1 at 200 mA g-1. In particular, superior cycling stability of 165.2 mA h g-1 at 1000 mA g-1 and 129.7 mA h g-1 at 2000 mA g-1 can be retained after 1500 cycles, respectively. Quantitative analysis reveals that this optimized structure leads to an enhanced surface-controlled contribution, resulting in fast potassiation kinetics and electronic|ionic conductivities, which are regarded as essential features for potassium storage. Our findings in this work provide an efficient strategy to significantly improve potassium storage capacity while maintaining a high ICE for hard carbon electrodes.

The oxygen evolution reaction (OER) is a vital proton donor for various clean energy technologies. Here, we synthesized IrOx-decorated ultrathin NiFe-LDH nanosheets (thickness 1–2 nm) by a one-step co-precipitation method. The IrOx was uniformly dispersed on the surface of ultrathin NiFe-LDH nanosheets, greatly increasing the active sites and the electric conductivity for NiFe-LDH. As a result, the IrOx/U-NiFe-LDH exhibited excellent OER performance with a low overpotential (236 mV) and a Tafel slope (74.3 mA dec−1).

Metallic-phase selenide molybdenum (1T-MoSe

Lithium-ion batteries based on single-crystal LiNi

Developing suitable electrode materials capable of tolerating severe structural deformation and overcoming sluggish reaction kinetics resulting from the large radius of potassium ion (K

Ag-based bonding wires were generally accepted as the most promising material to substitute for Au bonding wires, however, the electrolytic migration concern of Ag limited its industrial application in electronic packaging, especially in ultra-fine pitch wire bonding. In the present study, the electrolytic migration behaviors of Au-coated Ag bonding wires and Ag wires were studied through water drop tests. The dendrites’ growth and morphology evolution were investigated by in-situ optical microscope observation and the microstructure of the cathodic and anodic bonding wires were characterized by scanning electron microscope test. It could be seen that when comparing Au-coated Ag bonding wires with Ag wires, the dendrite assembled by a large number of Ag nanoparticles grew much more slowly from cathode to anode. The Ag2O particle layer on the anodic wires was thinner, the dendrite contact time was delayed and the current densities at the dendrite contact time were much smaller when the Au coating layer exist. The above results show that Au coating could act as a barrier to inhibit electrolytic migration, which has contributed to electronic packaging applications of Au-coated Ag bonding wires.

Transition metal dichalcogenides are regarded as promising anode materials for potassium-ion batteries (PIBs) because of their high theoretical capacities. However, due to the large atomic radius of K

The travel delay caused by incidents severely reduces the efficiency of traffic. This symptom has been relieved with the development of advanced communication technologies. However, the emergency traffic information (ETI) is meaningless for vehicles which do not traverse the incident segment. Unlike most existing studies concentrating on the network performance during the dissemination of ETI to all vehicles, this paper proposes a joint traffic-communication optimization strategy (JTCS) to reduce the extra cost caused by unnecessary communication, which minimizes the total communication and traffic cost by transmitting the ETI to the worthy vehicles who need the ETI. Specifically, we capture the optimal targeted ETI transmission strategy with combination of radio resource allocation strategy (RRAS) and traffic-influencing transmission strategy (TTS), which can be converted into a bi-level optimization problem. The lower-level problem minimizes the total cost by Lagrangian method and obtains the optimal RRAS when the TTS is given. The upper-level problem develops the optimal TTS based on the optimal RRAS obtained in the lower-level problem. Simulation results using SUMO and MATLAB indicate that JTCS can achieve minimal total cost of ETI transmission and vehicle rerouting by comparing with existing approaches.

Si-based anode materials have attracted considerable attention because of their ultrahigh reversible capacity. However, poor cycling stability caused by the large volume change during cycling prevented the commercial application of Si anodes for lithium-ion batteries (LIBs). To overcome these challenges, in the present study, we designed a nitrogen plasma-treated core-bishell nanostructure where the Si nanoparticle was encapsulated into a SiOx shell and N-doped TiO2-δ shell. Here, the SiOx inside the shell and the TiO2 outside the shell act as binary buffer matrices to accommodate the large volume change and also help to stabilize the solid electrolyte interphase films on the shell surface. More importantly, the plasma-induced N-doped TiO2-δ shell with many Ti3+ species and oxygen vacancies plays a key role in improving the electrical conductivity of Si anodes. Owing to the synergistic effects of SiOx and N-doped TiO2-δ bishells, the cycling stability and rate performance of Si anodes are significantly enhanced. The as-obtained sample exhibits superior cycling stability with a capacity retention of 650 mA h g-1 at 200 mA g-1 after 300 cycles. This strategy is favorable for improving the electrochemical performances of Si-based anodes to employ in practical LIBs.

Tyrosine hydroxylase (TH) is the initial enzyme responsible for cuticle sclerotization and pigmentation in many insect species, but to date, no direct functional studies have focused on TH in Zeugodacus tau. Here, the 3336-bp full-length cDNA of TH was isolated from Z. tau, a notorious horticultural pest infesting fruits and vegetables. qRT-polymerase chain reaction revealed that ZtTH transcripts were highly abundant at the time of pupal tanning and during adult emergence and were expressed in the midgut, integument and head of molting larvae. The pupation and eclosion rates gradually decreased when the 1st-instar larvae were fed diets containing higher concentrations of the TH inhibitor 3-iodo-tyrosine (3-IT). Moreover, pupal weights were significantly decreased, and abnormal uncolored phenotypes were observed after 20 mg/g 3-IT was incorporated into the diet. In addition, the suppression of TH function (mediated by RNA interference) led to a decrease in TH mRNAs and eclosion rates, accompanied by less-pigmented phenotypes. There was a severe impairment of larval-pupal cuticle tanning, leading to pupae with less yellowish pigment or that were completely white and transparent, when we injected 2 μL of 24.4 mM or 73.27 mM 3-IT into 3rd-instar larvae or prepupae. These results suggest that TH is an important enzyme for the normal growth and pupal pigmentation of Z. tau and that TH is a potential gene target for use in the control of Z. tau.

For Ni-Mn-Z based (Z = Sn, In, Sb) alloys, the martensite transformation (MT) and magnetic transition in austenite state create opposite magnetic cooling effect, which offsets each other when the first-order MT (FOMT) coincides with the second-order magnetic transition (SOMT). In the present study, two successive magnetization peaks are introduced in a Ni48.4Fe1.1Mn38.5Sn12.0 alloy by creation of a partial overlap between reverse MT and magnetic transition in the austenite phase with 1.1 at.% Fe-doping. In addition, significant enhancement of the magnetization difference (ΔM) between martensite/austenite phases is achieved. Consequently, an inverse magnetocaloric effect (IMCE) associated with a positive isothermal magnetic entropy change (ΔSM) of 9.6 J/kg∙K and a working temperature interval (ΔTFWHM) of 306–314 K is found under an external magnetic field of 5.0 T in the reverse MT and TCA temperature range. This IMCE is followed by a conventional magnetocaloric effect (CMCE) with a negative ΔSM of −2.7 J/kg∙K and ΔTFWHM of 316–339 K under 5.0 T. By taking advantage of these two successive MCEs using a special designed device, large caloric cooling effect with enhanced working temperature interval may be of interesting for practical room-temperature refrigeration applications.

Diachasmimorpha longicaudata is the most widely used endoparasitoid in biocontrol programmes against various species of tephritids and is continuously mass-reared under laboratory conditions at a constant temperature; however, little is known about how varying the temperature might affect the effectiveness of the mass rearing of immature D. longicaudata. This study aimed to determine the optimum temperature for the development of larvae D. longicaudata the larvae of its host, Bactrocera dorsalis. Third-instar B. dorsalis were exposed for 4 h to five pairs of parasitoids, and then they were kept at one of six temperatures ranging from 19°C to 34°C. The activities of three major antioxidant enzymes (CAT, POX, SOD) were individually measured 4, 24, 48 and 72 h after exposure to each of the six temperatures. The results were as follows: for CAT the highest CAT activities were recorded at 25°C (intervals 5-24 h and 25-48 h), at 28°C (interval 0-4 h) and at 31°C (interval 49-72 h), and for POX and SOD identically at 25°C (intervals 0-4 h, 5-24 h) and at 31°C (intervals 25-48 h, 49-72 h), respectively. Subsequently, the effects keeping the parasitized larvae at these different temperatures on the biological attributes of D. longicaudata reared under laboratory conditions were investigated. The percentage of their eggs that hatched, percentage of adults that emerged, pupal weight and longevity were significantly greater than that recorded for the control when the parasitized host larvae were kept at 28°C for 4 h, 25°C for 5 and 48 h and 31°C for 49 and 72 h.