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Lacquer wood (LW) goes through one-step and two-step H3PO4 activation process to prepare activated carbons (ACs) at different temperature, and its performance was evaluated by testing CV, EIS, GCD and cycling respect to an electrode material in supercapacitors. The performance of lacquer wood activated carbon prepared by different activation methods and temperature (300, 400, 500, 600, 700, and 800 °C) was studied, and the influence on its electrochemical properties provides valuable guidance for the high-efficient energy utilization of lacquer wood. The results showed that the AC generated via one-step activation process at 400 °C demonstrate excellent specific surface area (SBET 1609.09 m2/g) than those from two-step activation method. Besides, the biomass-derived ACs presented overall better electrochemistry characteristic than those from charcoal-derived ACs. The largest specific capacitance (354 F/g) was obtained in the ACs-based electrodes which was generated from one-step activation process (activated at 600 °C). After 10000 cycles, its capacity retention reached 95.3%, which provides a meaningful guidance into the application of energy storage supercapacitors. This study proves that the LW derived ACs are promising electrodes of the high-performance supercapacitors, which is beneficial for value-added and industrial supercapacitors application of lacquer wood ACs.

Solar-driven hydrogen peroxide (H2O2) production presents unique merits of sustainability and environmental friendliness. Herein, efficient solar-driven H2O2 production through dioxygen reduction is achieved by employing polymeric carbon nitride framework with sodium cyanaminate moiety, affording a H2O2 production rate of 18.7 μmol h −1 mg−1 and an apparent quantum yield of 27.6% at 380 nm. The overall photocatalytic transformation process is systematically analyzed, and some previously unknown structural features and interactions are substantiated via experimental and theoretical methods. The structural features of cyanamino group and pyridinic nitrogen-coordinated soidum in the framework promote photon absorption, alter the energy landscape of the framework and improve charge separation efficiency, enhance surface adsorption of dioxygen, and create selective 2e− oxygen reduction reaction surface-active sites. Particularly, an electronic coupling interaction between O2 and surface, which boosts the population and prolongs the lifetime of the active shallow-trapped electrons, is experimentally substantiated., Solar-driven H2O2 production presents a renewable approach to chemical synthesis. Here, authors perform a mechanistic analysis on the contribution of the sodium cyanaminate moiety to the 2-electron oxygen reduction reaction performance of polymeric carbon nitride frameworks.

Exfoliated and plicated g-C3N4 nanosheets (CNsF) were prepared through a thermal-chemical exfoliation in which the bulk g-C3N4 was obtained first under thermal exfoliation, and then was exposed to an acidic etching using hydrofluoric acid under hydrothermal condition. The acidic etching not only exfoliated g-C3N4 nanosheets by disrupting weak van der Waals forces between layers, which led to formation of a monolayer or a few layers of g-C3N4 nanosheets, but also made disordered defects on its surface and created plicated g-C3N4 nanosheets. Under visible-light illumination, the optimized sample (CNsF-6%) showed a hydrogen evolution rate of 54.13 μmol h−1g−1 (without co-catalyst) and a specific surface area of 121.4 m2 g−1, which were about 4.7 and 2.5 times, respectively, higher than pristine g-C3N4. It also showed remarkably enhanced photocatalytic performance in removing various organic pollutants. This remarkable improvement probably arises from the porous nanosheets and an increased number of active sites resulting from the CNsF, which subsequently enhanced the charge separation efficiency. This work provided an alternative way to obtain highly active g-C3N4 photocatalysts.

Cell-aware test (CAT) explicitly targets faults caused by defects inside library cells to improve test quality, compared with conventional automatic test pattern generation (ATPG) approaches, which target faults only at the boundaries of library cells. The CAT methodology consists of two stages. Stage 1, based on dedicated analog simulation, library characterization per cell identifies which cell-level test pattern detects which cell-internal defect; this detection information is encoded in a defect detection matrix (DDM). In Stage 2, with the DDMs as inputs, cell-aware ATPG generates chip-level test patterns per circuit design that is build up of interconnected instances of library cells. This paper focuses on Stage 1, library characterization, as both test quality and cost are determined by the set of cell-internal defects identified and simulated in the CAT tool flow. With the aim to achieve the best test quality, we first propose an approach to identify a comprehensive set, referred to as full set, of potential open- and short-defect locations based on cell layout. However, the full set of defects can be large even for a single cell, making the time cost of the defect simulation in Stage 1 unaffordable. Subsequently, to reduce the simulation time, we collapse the full set to a compact set of defects which serves as input of the defect simulation. The full set is stored for the diagnosis and failure analysis. With inspecting the simulation results, we propose a method to verify the test quality based on the compact set of defects and, if necessary, to compensate the test quality to the same level as that based on the full set of defects. For 351 combinational library cells in Cadence’s GPDK045 45nm library, we simulate only 5.4% defects from the full set to achieve the same test quality based on the full set of defects. In total, the simulation time, via linear extrapolation per cell, would be reduced by 96.4% compared with the time based on the full set of defects.

For the thin-film thermocouple with ITO/In2O3 as the functional layer, the mechanical reliability of their composite multilayer membrane structures under high temperature and random vibration conditions are discussed. Using the elastic plasticity model based on the finite element simulation method, the stress and strain distribution patterns caused by the thermal mismatch and vibration of multilayer film materials are systematically analyzed, and the distribution of the stress concentration and strain accumulation regions that may lead to fatal reliability problems are characterized. When a thermal load of 1000 °C is applied, the protective layer of the structure is vulnerable to severe stress environment. In addition, plastic deformation occurs in the adjacent layers of the functional layer, making it a weak reliability area. The stress generated by the vibration load is much smaller than the thermal stress, which mainly occurs at the roots of the structure, where prolonged loading may lead to fatigue failure.

The deformation mechanism of C5191 phosphor bronze sheet under ultra-high-speed blanking was investigated. By virtue of a DOBBY-OMEGA F1 ultra-high-speed press, the ultra-high-speed blanking test was conducted on C5191 phosphor bronze sheets with a thickness of 0.12 mm at 3000 strokes per minute. The microstructures of the blanked edges were characterized and analyzed separately by electron back-scatter diffraction (EBSD) and transmission electron microscopy (TEM). The results show that grains in the blanked edges are stretched along the blanking direction. Strong {001}〈100〉 cube textures (maximum pole densities of 9 and 12, respectively) and secondarily strong {011}〈011〉 textures (maximum pole densities of 4 and 7, respectively) are formed in local zones. Additionally, deformation twins are found in the shear zone of the blanked edges which are rotated and coarsened due to the blanking-induced extrusion and local thermal effect which can further form into sub-grains with clear and high-angle boundaries. The C5191 phosphor bronze sheet is subjected to adiabatic shear during ultra-high-speed blanking, accompanied with dynamic recrystallization.

Only a few known epoxide hydrolases (EHs) displayed activity towards o-nitrostyrene oxide (4a), presumably owing to the large steric hindrance caused by o-nitro substituent. Therefore, excavating EHs with high activity and enantio- and/or regio-selectivity towards racemic (rac-) 4a is essential but challenging. Here, AuEH2 from Aspergillus usamii was expressed in E. coli BL21(DE3). E. coli/Aueh2, an E. coli transformant expressing AuEH2, possessed EH activities of 16.2–184 U/g wet cell towards rac-styrene oxide (1a) and its derivatives (2a–13a), and the largest enantiomeric ratio of 96 towards rac-4a. The regioselectivity coefficients, βR and βS, of AuEH2 were determined to be 99.2% and 98.9%, suggesting that it regiopreferentially attacks the Cβ in the oxirane rings of (R)- and (S)-4a. Then, the nearly perfect kinetic resolution of 20 mM rac-4a in pure water was carried out using 20 mg/mL wet cells of E. coli/Aueh2 at 25 °C for 50 min, retaining (S)-4a with over 99% ees and 48.9% yields, while producing (R)-o-nitrophenyl-1,2-ethanediol (4b) with 95.3% eep and 49.8% yieldp. To elucidate the molecular mechanism of AuEH2 with high enantiopreference for (R)-4a, its crystal structure was solved by X-ray diffraction and the molecular docking of AuEH2 with (R)- or (S)-4a was simulated.

In this study, the plasma oxidation effect in tin-oxide (SnOx) thin film was investigated. And on this basis, we fabricated n-type thin-film transistors (TFTs) using the SnOx thin film with the plasma oxidation by experiments. By adjusting the processing time of the oxygen plasma treatment (OPT), the optimized SnOx TFT device exhibited an extremely high field-effect mobility of 87.6 cm2 V−1 s−1, a desirable on-to-off current ratio of 1.9 × 104 and a threshold voltage of − 0.9 V. Furthermore, we investigated the origin of the performance enhancements in the n-type SnOx TFTs with the optimized OPT by introducing the density of states (DOS) modeling in TCAD simulation. The numerical simulation indicated that the attributes of donor-like Gaussian defect states (oxygen vacancies) were modified in overall DOS due to the plasma oxidation effect. These present results show that the SnOx TFT treated by oxygen plasma has great promise in the future high-performance flat panel display industries.

In this study, we investigated the stress and doping effects of ferroelectric hafnium zirconium oxide (HfZrO) based on material analysis and electrical characteristics. The experimental results revealed that the ferroelectric crystalline phase is effectively transferred by mechanical stress of tantalum nitride (TaN) electrodes, and the origin of stress is mainly the thermal residual stress formed near the TaN and HfZrO interface. The ferroelectric polarization characteristics of HfZrO can be further modified by additional Al doping, which not only improves the leakage current of HfZrO due to the large bandgap of Al2O3 but also simultaneously stabilizes the ferroelectric domain switching under a large coercive field.

Tungstic oxide (WO3) is a promising visible-light-responsive photoanode material, but it has poor charge transport and collection properties. In this study, a WO3/BiFeO3 core/shell photoanode (WO3/BFO) with enhanced photoelectrochemical (PEC) performance was successfully prepared using a facile spin-coating method. The optimal WO3/BFO shows an excellently enhanced and stable photocurrent density of ∼2.83 mA cm−2 at 0.6 V vs. Ag/AgCl, which is ∼244% more than WO3 under AM 1.5 illumination. The results of Mott–Schottky tests, intensity modulated photoelectrochemical spectroscopy and transient photocurrent decay indicated that the BFO ferroelectric nanolayer significantly enhances the charge density of the WO3/BFO, and improves its charge transport and separation property and charge lifetime, which could be the reason for the enhanced PEC activity of WO3/BFO.

Protein oxidation is a critical process in the deterioration and spoilage of fish and related commodities during processing and storage. In this study, the hydroxyl radical generation system (HRGS) was used to simulate the effect of oxidation on the functional, conformational and gelling properties of topmouth culter (Culter alburnus) myofibrillar proteins (MP). Additionally, the effects of oxidation on the gel-forming abilities of MP were also systematically analyzed from the perspective of intermolecular interaction forces. Oxidation was shown to decrease the total sulfhydryl content, increase the surface hydrophobicity, and induce conformational changes in MP. Rheological analysis showed that oxidation reduced the gel strength. Water holding capacity (WHC) and low-field nuclear magnetic resonance (LF-NMR) analyses showed that low oxidation could enhance water binding of protein matrix, while high-degree oxidation could substantially reduce the gelling properties of MP. The selective solubility of MP gel proved that oxidation could reduce the content of ionic and hydrogen bonds and increase hydrophobic interactions. All the results indicate that oxidation could alter the intermolecular interactions between protein-protein and protein-water molecules, due to irregular unfolding and inhibition of the cross-linking of amino acid side chains, leading to reduction in the quality and function of fish and related products.

In this study, a novel BiOBr/HPW/Au photocatalyst was prepared via hydrothermal method followed by photo-reduction method. The characterization results indicated the successful introduction of HPW and Au in BiOBr. BiOBr/HPW/Au exhibited excellent photocatalytic activity in RhB degradation. The degradation rate constant of BiOBr/HPW/Au was 3.55 times higher than that of BiOBr. Radical scavenger experiments showed that ·O−2 was the dominant reactive radical species. A possible mechanism of the enhanced photocatalytic activity was attributed to the synergistic effect of BiOBr, HPW and Au, which resulted in enhanced quantum efficiency and high light harvesting efficiency.

Long-term efficient separation of highly emulsified oily wastewater is challenging. Reported herein is the preparation of a reinforced superhydrophilic, underwater superoleophobic membrane with demulsification properties using active iron nanoparticles in situ generated on a polydopamine (PDA)/polyethylenimine (PEI)-modified polyvinylidene fluoride (PVDF) membrane surface. A stable zwitterionic structure is fabricated on the membrane surface and provides it with an excellent capability of binding a hydration layer, leading to enhanced superhydrophilic/underwater superoleophobic properties. The interaction between the membrane surface and water is quantified using the relaxation time of water. After iron nanoparticles in situ anchoring, the superhydrophilic, underwater superoleophobic PDA/PEI modified PVDF membrane shows more stable flux behaviors, higher oil separation efficiency, demulsification, and excellent antioil-fouling properties for various anionic, nonionic, and cationic surfactant-stabilized oil-in-water emulsions in a crossflow filtration system. The reinforced hydration layer and the amphoteric charged demusification properties of the membrane play important roles in enhancing the membrane separation performance. The reinforced membrane also exhibits excellent cleaning and reusability performance in long-term operations. The outstanding separation performance, as well as the simple and cost-effective fabrication process of the membrane with various favorable properties, highlight its promise in practical emulsified oily water applications.

W vacancies containing Bi2WO6 (VW-Bi2WO6) was synthesized by a reductant-involved hydrothermal process. The photoactivity of Bi2WO6 was enhanced by 3.3 times and the TOC removal rate increased from 38.3% to 64.7% after the introduction of surface W vacancies. Positron annihilation spectrometry (PAS), XPS, Raman spectra and other characterization results indicated that W vacancies existed on the catalyst surface. The surface W vacancies were proved to widen the band gap and negatively shift CB edge to produce more O2•− and photoexcited holes at catalyst surface, as confirmed by ESR and radicals trapping experiments. Further, according to the results of pyridine adsorbed FTIR and Zeta potentials, the enhanced interaction between pollutants and VW-Bi2WO6 was confirmed. As a result, the active species produced at surface were able to be accelerated to directly react with organic pollutants, leading to the highly efficient degradation and mineralization of pollutants in water.

Cooling shock can be considered a potential method of causing the high-temperature rocks to crack and achieve the most efficient exploitation and utilization of geo-thermal energy in the future. However, it is important to accurately recognize the thermal cracking effect and the corresponding typical characteristics of cooling shock. Therefore, in this study, we conducted a systematic experiment on the effects of cooling shocks with different temperature gradients on the cracking of high-temperature granite. The granite samples were heated to 150, 350, 550, and 750 °C, and then injected with three kinds of refrigerants of 20, 0 and − 20 °C into the granite boreholes. Furthermore, the cracking characteristics of granite were compared by means of optical microscope. According to the experimental analysis, several conclusions could be obtained: (1) Compared with natural cooling conditions, cooling shocks of 20, 0, and − 20 °C resulted in no evident open cracks on the granite at 150 and 350 °C; however, the distribution of the micro-crack networks became denser with a decrease in the refrigerant temperature. (2) For the high-temperature granite samples at 550 and 750 °C, the effect of the cooling shock was significant, and localized open cracks could be observed; however, several differences were evident in the effect of granite cracking under different combinations of cooling shocks and high temperatures. For granite with the same temperature gradient, with the decrease in the refrigerant temperature, the number of inter-granular and trans-granular cracks increased, and the cooling shock enhanced the cracking effect. (3) The main factor of granite cracking was the anisotropy of the mineral particles affected by the temperature difference, in which a large amount of quartz was contained in the granite, and the effect of repeated phase transformation near 573 °C was remarkable. Moreover, with the temperature difference between the refrigerant and the heated samples increasing, the generated tensile forces in the outer edge of samples would increase rapidly, causing amounts of trans-granular cracks and leading to the denser micro-crack networks. This work can provide an experimental reference for understanding the effect of cooling shock on mechanical properties and cracking of high-temperature rocks.

Today, many people use dashcams, and videos recorded on dashcams are often used as evidence of accident fault. People can upload videos of dashcam recordings with specific accident clips and share the videos with others who request them, by providing the time or location of an accident. However, dashcam videos are erased when the dashcam memory is full, so periodic backup is necessary for video sharing. It is inconvenient for dashcam owners to search for and transmit a requested video clip from backup videos. In addition, anonymity is not ensured, which may reduce location privacy by exposing the video owner’s location. To solve this problem, we propose a video sharing scheme with accident detection using deep learning coupled with automatic transfer to the cloud; we also propose ensuring data and operational integrity along with location privacy by using blockchain smart contracts. Furthermore, our proposed system uses proxy re-encryption to enhance the confidentiality of a shared video. Our experiments show that our proposed automatic video sharing system is cost-effective enough to be acceptable for deployment.

The objective of the study was to explore the formation mechanism and thermodynamic properties of chitosan (CS)–potato protein isolate (PPI) complex under DHPM treatment. The transmission electron microscopic (TEM) results showed the formation of a complex between CS and PPI. Meanwhile, particle size and zeta-potential were shown to increase with increasing CS concentration, further confirming the formation of the complex. The surface hydrophobicity results showed CS was bound to PPI by hydrogen bond. The ultraviolet and fluorescence spectral analysis exhibited CS formed a protective mechanism against PPI destruction, preventing the exposure of tyrosine and tryptophan residues. Infrared spectrum and circular dichroism spectral analysis revealed no occurrence of chemical reaction between CS and PPI under DHPM treatment, further indicating that they are bound by hydrogen bond and hydrophobic interaction. Moreover, CS addition was shown to enhance the intermolecular interaction and promote the formation of intermolecular hydrogen bond network. Differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA) revealed that CS addition could improve the thermal stability of PPI. These results have shed light on the formation mechanism and thermodynamic properties of the CS/PPI complex and facilitate its application in food industry.

An open reading frame of sleh1, a gene encoding for a novel epoxide hydrolase from Solanum lycopersicum (SlEH1), was amplified by RT-PCR and expressed in E. coli BL21(DE3). The substrate spectrum assay showed that E. coli/sleh1 had EH activities towards all tested substrates except for racemic (rac-) 5a, and the highest enantiomeric ratio (E > 200) towards rac-2a, retaining (R)-2a with 99.1% ees and 49.2% yields and affording (R)-2b with 89.8% eep and 46.7% yieldp. Besides, E. coli/sleh1 also hydrolyzed of rac-7a–9a with moderate regioselectivities, producing (S)- or (R)-7b–9b with 40.5–51.3% eep and 69.4–75.2% yieldp. The pH optimum and stability of the purified SlEH1 were 7.5 and at a range of 6.5–8.5, and it was thermostable at or below 40 °C. Its catalytic efficiency (kcatS/KmS = 7.49 mM−1 s−1) for (S)-2a was much higher than that for (R)-2a. The gram-scale kinetic resolution of 150 mM rac-2a was carried out by E. coli/sleh1 at 20 °C for 8 h, producing (R)-2a with 98.2% ees and 45.3% overall yields after purification by silica gel column chromatography. Furthermore, the source of extremely high enantioselectivity of SlEH1 towards rac-2a was analyzed by molecular docking simulations.

Sodium hypochlorite (NaClO) solution is a typical cleaning agent for membrane fouling. However, it can damage membrane chemical structures and produce toxic disinfection byproducts, which in turn reduces the membrane performance. This study focuses on the fabrication of active membranes thereby overcoming the limitations of chemical cleaning. A hierarchical active poly(vinylidene fluoride) membrane with polydopamine/polyethyleneimine (PEI) co-supported iron nanoparticle (Fe NP) catalysts was successfully constructed and denoted as a Fe-HP-membrane. The Fe-HP-membrane exhibited excellent advanced oxidation activity with maximum flux recoveries (∼85% with bovine serum albumin [BSA] and ∼95% with humic acid [HA] solutions). After the static experiment of ∼30 days, the BSA proteins and HA successfully desorbed from the membrane surface. Especially, with a trace amount of hydrogen peroxide (H2O2) flowing over the surface of the Fe-HP-membrane, highly exposed active sites were observed. Membrane cleaning showed that the "outside-to-in" active surfaces generated considerable amounts of •OH radicals at the interface of BSA or HA and the fouled membrane. As a result, the unwanted foulants were successfully removed from the membrane interface, enabling multiple use of the Fe-HP-membrane. Therefore, backwashing with a small amount of H2O2 (0.33 wt %) covered ∼20% of the flux. In contrary, backwashing with NaClO (1 wt %) can only achieve a flux recovery of ∼10% after six consecutive BSA filtration cycles. The Fe-HP-membrane exhibited better HA foulant removal (a flux recovery of ∼51%) after backwashing with H2O2 than using NaClO (a flux recovery of ∼43%). Our findings demonstrate a new platform for water treatment and regeneration of fouled membranes.

Many organic pollutants are rich in electrons, which are not used in the current pollutant removal technology, resulting in high energy consumption and low efficiency. To achieve a sustainable conversion of pollutants using Fenton-like technology, surface electron distribution-polarized lotus flower-like Fe-doped polyimide hybrid nanosheets (lf-Fe/PI HNs), a Fenton-like catalyst, are first developed for electron transfer and storage between pollutants and H2O2. Fe2+/Fe3+ ions are found in the framework of lf-Fe/PI HNs and directly bond with the C and N species of polyimide to form C–Fe–N–C in a closed loop. The experimental results and theoretical calculations demonstrate that electron-rich Fe and electron-deficient C areas are produced in the C–Fe–N–C of lf-Fe/PI HNs. This novel structure type in Fe-based materials leads to an excellent Fenton-like catalytic performance and efficiency for the refractory pollutant degradation under neutral conditions. The reaction rate is found to be 7–10 times higher than that of the conventional Fe-based Fenton-like catalyst. The reaction mechanism revealed that H2O2 is reduced to ˙OH radicals (further attacking pollutants) in the electron-rich Fe areas, and pollutants are mainly oxidized and degraded by providing electrons for the electron-deficient C areas. Fe–N–C acts as a bridge for electron transfer and electron storage carriers between pollutants and H2O2. This process enables the sustainable use of the electrons of pollutants, thereby greatly reducing the energy consumption for water treatment.

In this work, we demonstrated a HfO2-based ferroelectric field-effect transistor (FeFET) in series with a HfAlO ferroelectric capacitor for memory application and further investigated the impact of the ferroelectric capacitor with different thicknesses and areas. It was revealed that the memory window of the FeFET has a significant correlation with the ferroelectric capacitor from the transfer curves of the transistor after the series connection. By decreasing the thickness and area of the ferroelectric capacitor, the memory window of the FeFET was improved, which could be verified through the TCAD simulation tool and capacitance matching model. With the series-connected ferroelectric capacitor, in addition to optimizing the characteristics of ferroelectric memory, we can effectively avoid the interface-caused undesirable effects in conventional ferroelectric memory during film stacking. These results provide a solution for future low-power embedded memory application.

In this paper, we investigated the performance of an n-type tin-oxide (SnOx) thin film transistor (TFT) by experiments and simulation. The fabricated SnOx TFT device by oxygen plasma treatment on the channel exhibited n-type conduction with an on/off current ratio of 4.4×104, a high field-effect mobility of 18.5 cm2/V.s and a threshold swing of 405 mV/decade, which could be attributed to the excess reacted oxygen incorporated to the channel to form the oxygen-rich n-type SnOx. Furthermore, a TCAD simulation based on the n-type SnOx TFT device was performed by fitting the experimental data to investigate the effect of the channel traps on the device performance, indicating that performance enhancements were further achieved by suppressing the density of channel traps. In addition, the n-type SnOx TFT device exhibited high stability upon illumination with visible light. The results show that the n-type SnOx TFT device by channel plasma processing has considerable potential for next-generation high-performance display application.

Two-dimensional (2D) topological insulators (TIs) have attracted a lot of attention owing to their striking optical nonlinearity. However, the ultra-low saturable intensity (SI) of TIs resulting from the bulk conduction band limits their applications, such as in mode-locking solid-state lasers. In this work, through fabricating a graphene/Bi2Te3 heterojunction which combines monolayer graphene and a Bi2Te3 nanoplate, the optical nonlinearities are analyzed. Moreover, the thickness-dependent characteristics are also investigated by varying the thickness of the Bi2Te3 when synthesizing the heterojunctions. Furthermore, with the aid of the estimated junction electron escape time, a model of the photo-excited carrier-transfer mechanism is proposed and used to describe the phenomena of depression of ultra-low saturable absorption (SA) from the Bi2Te3 bulk band. The increased modulation depth of the graphene/Bi2Te3 heterojunction can accordingly be realized in more detail. In addition, a Q-switched solid-state laser operating at 1064 nm with heterojunction saturable absorbers is built up and characterized for validating the proposed model. The laser performance with varied Bi2Te3 thickness, such as pulse duration and repetition rate, agrees quite well with our proposed model. Our work demonstrates the functionality of optical nonlinear engineering by tuning the thickness of the graphene/Bi2Te3 heterojunction and demonstrates its potential for applications.

Peroxymonosulfate (PMS) activation in heterogeneous processes for pollutant removal is a promising water treatment technique. However, the existing rate limiting step of the metal-containing system greatly restrains its performance and increases the consumption of PMS and energy. Herein, we describe an efficient, metal-free strategy for solving these problems. In this study, L-ascorbic acid O-doped carbon–nitrogen–oxygen polymer nano-flowers (OVc-CNOP Nfs) were fabricated via a facile thermal polymerization process. The metal-free OVc-CNOP Nfs showed excellent activity and stability in PMS activation for the degradation of various organic pollutants. Even the refractory endocrine interferon bisphenol A can be completely removed in just 1 min. Doping with O induced bidirectional transfer of electrons on aromatic rings through C–O–C bonding [C(π)→O←C(π)], which led to the formation of micro-electronic fields on the catalyst surface. During the reaction, efficient oxidation of organic pollutants by utilizing the charges of pollutants themselves around the electron-poor C(π) areas inhibited undesirable oxidation of PMS and promoted PMS reduction in the electron-rich O areas to generate hydroxyl (˙OH) and sulfate (SO4˙−) radicals. The reduction of dissolved oxygen to O2˙− around the electron-rich O areas also destroyed the pollutants, and this further drove electron donation from the pollutants and accelerated catalytic oxidation. These multi-pathway synergistic processes involving oxidation of the pollutants themselves and attack by free radicals enabled rapid degradation of contaminants.

Transparent electronics has attracted much attention and been widely studied for next-generation high-performance flat-panel display application in the past few years, because of its excellent electrical properties. In display application, thin film transistors (TFTs) play an important role as the basic units by controlling the pixels. Among them, oxide-based TFTs have become promising candidates and gradually replaced the conventional amorphous and polycrystalline silicon TFTs, due to high mobility, good transparency, excellent uniformity and low processing temperature. Even though n-type oxide TFTs have shown high device performance and been used in commercial display application, p-type oxide TFTs with the equal performance have been rarely reported. Hence, in this paper, recent progress and challenges in p-type oxide-based TFTs are reviewed. After a short introduction, the TFT device structure and operation are presented. Then, recent developments in p-type oxide TFTs are discussed in detail, with the emphasis on the potential p-type oxide candidates as copper oxide, tin oxide and nickel oxide. Moreover, miscellaneous applications of p-type oxide TFTs are also presented. Despite this, the performance of p-type oxide TFTs still lags behind, as compared with that of n-type counterparts. Thus, the current issues and challenges of p-type oxide TFTs are briefly discussed.

Optimal device integrity was achieved in Ni/SiGeOx/TiOy/TaN resistive memory by using a forming-free switch with a low switching power of 790 μW, stable endurance of 104 cycles, optimal retention time of 105 s, resistance window of at least 1150×, and tight current distributions at 85 °C. These characteristics are attributed to the low current switching obtained using SiGeOx with a high oxygen vacancy density and highly defective TiOy grain boundaries.

The solid-solid or solid-liquid interfaces are vital for the photocatalytic reaction. Herein, AgI nanoparticles (NPs) attached on the (0 1 1) plane of Ag2WO4 nanorods were synthesized by a facile method at room temperature. The co-crystalization of the two components caused their phase transformation and the existence of a strong interface interaction. Meanwhile, the porous batt-like morphology of AgI NPs provided more contact sites for organic pollutants to induce a strong interaction at the solid-liquid interface. The heterojunction nanocatalyst was found to be highly effective for the degradation and mineralization of various pollutants, including the endocrine-disrupting chemical bisphenol A, the antibiotics sulfamethoxazole and ciprofloxacin, and the azo-dye methyl orange under visible light (λ > 420 nm). Its photocatalytic rate was 91, 52, and 39 times higher than that of bulk AgI, standard TiO2-xNx, and the physical mixture of the two components, respectively. Further studies demonstrated that the strong interactions between the two components and the pollutants promoted the electron transfer from organic pollutants to AgI NPs and then from AgI NPs to Ag2WO4 nanorods, resulting in the rapid oxidation of pollutants and the formation of Ag NPs. The newly formed Ag NPs further accelerated the degradation of pollutants due to a SPR effect and an empty levels feeding role to produce h+ on Ag2WO4, which can oxidize surface-adsorbed H2O into OH. This photocatalytic system provided a platform for understanding solid-solid and solid-liquid interface interaction and a novel design idea for water pollutants removal.

Nanoscaled Ti1-xSixN/CrAlN multilayers combining the cutting edges of Ti1-xSixN and CrAlN coatings are currently the focus of attention of researchers. Here, the structural, mechanical, and thermal properties of Ti1-xSixN/CrAlN multilayers with varied Si content were investigated. The hardness values of Ti1-xSixN/CrAlN multilayers are individually enhanced to 30.7 ± 1.0 GPa for x = 0, 36.0 ± 1.3 GPa for x = 0.13, and 35.9 ± 1.5 GPa for x = 0.22 from the 27.4 ± 0.3 GPa for CrAlN due to interfacial strengthening effect. Ti1-xSixN insertion layers retard the thermal decomposition process of CrAlN. After annealing at 1200 °C, the hardness of Ti1-xSixN/CrAlN (x = 0, 0.13, 0.22) multilayers is individually enhanced by ∼6.9, 12.9 and 13.6 GPa from the 18.7 ± 1.1 GPa for Cr0.32Al0.68N. However, Ti1-xSixN insertion layers lead to a drop in the oxidation resistance of CrAlN coatings due to their inferior oxidation resistance. Noticeable is that increasing Si content of Ti1-xSixN/CrAlN multilayers causes a decline in the thickness of oxide scales.

In this paper, the effect of channel annealing and oxygen flow rate in P-type tin-monoxide (SnO) thin film transistor (TFT) was investigated to reach the process compatibility with n-type oxide-based TFT. The optimized P-type SnO TFT with a small threshold voltage of -0.1 V, a high field-effect mobility of 4 cm² V-1 s-1 and an on/off current ratio of >10² was proposed. From the experimental results, the 150 °C channel annealing revealed a metallic behavior but a semiconductor-like property at a higher 200 °C that was favorable for transistor rectification. Besides, the higher oxygen flow rate was also helpful for improving device mobility and driving current, but shows a slight increase in off-state leakage, which is unavoidable due to the increase of grain in SnO channel.

In this study, the effect of the grain boundary density on the transport properties of the Re-substituted higher manganese silicide Mn30.4Re6Si63.6 has been investigated. The efficiency of electric...

In this work, we successfully demonstrated the 9.6-nm-thick HfAlOx ferroelectric memory using light aluminium doping of 6.5% to form ferroelectric orthorhombic phase. Compared to ferroelectric HfZrOx film with zirconium diffusion issue, the HfAlOx film showed excellent thermal stability under high temperature annealing. Besides, the ferroelectric HfAlOx also exhibited robust polarization characteristics under endurance cycling test. A >106 stressed cycles with 4 MV/cm can be measured and a long endurance was sustained over 5 × 107 cycles under 3.6 MV/cm. Therefore, the HfAlOx film showed the great promise for integrating in high performance ferroelectric memory with thermal budget concerns.

A novel ternary Au NPs/g-C3N4/BiOBr Z-scheme heterojunction composite was fabricated through hydrothermal and in-situ reduction method, and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, ultraviolet-visible diffuse reflection spectroscopy and photoluminescence emission spectroscopy. The photocatalytic activity was evaluated by the degradation of phenol under visible-light irradiation. It was found that Au NPs/g-C3N4/BiOBr showed enhanced photocatalytic activity, which is 3-fold higher than g-C3N4 and 2.5-fold higher than BiOBr. This could be attributed to the effective separation of photogenerated electron-hole pairs, narrowed band gap (2.10 eV) and surface plasmon resonance (SPR).

The BGP suffers from numerous security vulnerabilities, for example, fake routing updates incurring traffic hijacking and interception. The BGPsec protocol is supposed to fix these vulnerabilities by attesting routing updates. Although the BGP security problem has been extensively studied, the security of BGP with BGPsec is not well studied yet. We argue that even secured with BGPsec, BGP still has inherent security vulnerabilities. In particular, traffic can still be hijacked. In this article, we systematically study the vulnerabilities of BGP with BGPsec. We find that the protocol still cannot achieve the desired security guarantee of inter-domain routing. In particular, it is unable to ensure correct packet delivery on the Internet. We measure the impacts of the vulnerabilities by using a real data trace, and discuss enhancements to the design and the implementation of the secure BGP protocol, which allows BGP to achieve strong secure inter-domain routing.

A visible-light-driven photocatalyst nitrogen-deficient mesoporous graphitic carbon nitride (mpg-C3N4-δ) was prepared by a thermal polymerization-assisted colloidal crystal templating method. The unique mesoporous structure of mpg-C3N4-δ was confirmed to be formed with relatively uniform pores and cyano groups ( C N)-related nitrogen defects, which were generated from the break of the C N bonds of triazine rings and the subsequent loss of terminal NHx species during the pore-making process. Benefiting from the larger surface area, suitable energy level and increased unpaired electrons on C atoms of aromatic rings, the photocatalytic activity of mpg-C3N4-δ for RhB degradation was 11 and 2.6 times higher than that of bulk g-C3N4 and mpg-C3N4, respectively, under visible light irradiation (λ ≥ 420 nm). Furthermore, nitrogen defects in mpg-C3N4-δ were verified to serve as electron/hole traps to boost the separation and transfer of photoexcited charge carriers and thus enhanced the production of main active species h+ and O2 −, resulting in the efficient destruction of the intrinsic structure and functional groups of RhB molecules into small molecules. This work highlights that construction of uniform mesoporous architectures with surface nitrogen defects could be useful for developing highly efficient metal-free photocatalysts.

Ag/Ta2O5/CuO/Pt memristive devices with Ag point contacts at the interface exhibit forming-free and partial volatile analog resistive switching properties. Versatile synaptic functions, like the short-term plasticity, the long-term potentiation and the paired-pulse facilitation, are emulated with these devices. The Ag point contacts in the Ta2O5 layer are verified through transmission electron microscope (TEM) and X-ray photoelectron spectroscope (XPS). The Ag point contacts at the interface endow the device the transition from the electrochemical metallization mode to the valence change mode, and the analog resistive switching behavior and neuromorphic functions. This interface engineering of introducing point contacts at the interface provides a way for the development of neuromorphic devices with low power consumption. Keywords: Artificial synapse, Memristive device, Ag point contacts, Short-term plasticity, Long-term potentiation

Energy is required for networking and computation and is a valuable resource for unplugged systems such as mobile, sensor, and embedded systems. Energy denial-of-service (DoS) attack where a remote attacker exhausts the victim’s battery via networking remains a critical challenge for the device availability. While prior literature proposes mitigation- and detection-based solutions, we propose to eliminate the vulnerability entirely by offloading the power requirements to the entity who makes the networking requests. To do so, we build communication channels using wireless charging signals (as opposed to the traditional radio-frequency signals), so that the communication and the power transfer are simultaneous and inseparable, and use the channels to build power-positive networking (PPN). PPN also offloads the computation-based costs to the requester, enabling authentication and other tasks considered too power-hungry for battery-operated devices. In this article, we study the energy DoS attack impacts on off-the-shelf embedded system platforms (Raspberry Pi and the ESP 8266 system-on-chip (SoC) module), present PPN, implement and build a Qi-charging-technology-compatible prototype, and use the prototype for evaluations and analyses. Our prototype, built on the hardware already available for wireless charging, effectively defends against energy DoS and supports simultaneous power and data transfer.

A series of bismuth oxybromide photocatalysts were fabricated via a one-step hydrothermal method through pH value adjustment. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV-vis diffuse reflectance spectroscopy (UV-vis DRS) and photoluminescence spectroscopy (PL). The photocatalytic activities of the as-prepared samples were examined by degradation of Rhodamine B (RhB), methyl orange (MO) and phenol. The results indicate that the B9 displayed the highest photocatalytic activities. The enhanced photocatalytic activity can be attribute to enhanced absorption in the visible region and the decreased recombination efficiency of photogenerated charge carriers. The effect of hydrothermal pH value on the composition and morphology was explored and a synthesis process of bismuth oxybromide was proposed.

Consumption of additional H2O2 is necessary in classical Fenton catalysis. Herein, we report a novel and special nanocatalyst consisting of CoMoS2 nanosphere-embedded, reduced graphene oxide (rGO) nanosheets (CMS-rGO NSs). This nanocatalyst was discovered to have an impressive reactivity for in situ generation and synchronistical activation of H2O2 in different active centers, yielding fast and efficient degradation of the pollutants. The reaction rate is ∼21 times higher than that of conventional Fenton catalysts. The characterization shows that countless flower-like CoMoS2 nanospheres are uniformly embedded in the rGO nanosheets through Mo S C bonding bridges in CMS-rGO NSs, which leads to activation of the π electrons and their transfer from rGO to the metal centers (π → M). The formed Mo O Co further leads to a distribution of orientations of the electrons around the metal centers due to the different electronegativity of Mo and Co. During the reaction, the dissolved O2 is efficiently reduced to HO2 /O2 − around the electron-rich Mo center, and HO2 /O2 − is further reduced to H2O2 around the Co center. The generated H2O2 is finally reduced to OH for degrading dyes in the electron-rich metal (Mo or Co) centers of CMS-rGO NSs. The dye pollutants also act as electron donors, and they are directly degraded in the electron-poor π-center of CMS-rGO NSs, which promote the electron transfer cycle and achieve electron gain-loss balance. This discovery provides a new strategy for H2O2 generation-activation and pollutant degradation through constructing electron transfer bridges over the surface of catalysts.

A powerful technique to detect bone biomarkers has been developed for assessment of osteoporosis at the early stage. Two-dimensional multilayered gold-nanoparticle thin film (MTF-AuNPs) was demonstrated as a promising test platform for detection of bone biomarker, hydroxyproline (HYP), measured by surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). With strong surface plasmon resonance and excellent homogeneity, facilely prepared, highly ordered, and large-scale MTF-AuNPs revealed high sensitivity of HYP in the SALDI-MS measurement without additional matrixes, such as α-cyano-4-hydroxycinnamic acid (CHCA) and 2,5-dihydroxybenzoic acid (DHB). Furthermore, the mass spectrum of HYP with MTF-AuNPs was significantly improved in signal intensity enhancement, background noise reduction, and signal-to-noise ratio amplification. The excellent reproducibility of HYP spectra with only 9.3% relative signal variation could be attributed to MTF-AuNPs’ high absorbance at a wavelength of 337 nm, low heat capacity, superior thermal conductivity, and outstanding homogeneity. The calibration curve showed high linear correlation between mass spectrum intensity and HYP concentration in the range of 1 to 100 μM, covering the whole level in healthy people and osteoporosis patients. In particular, the serum sample was directly deposited onto the MTF-AuNP sample substrate without any pretreatment and its HYP concentration was then successfully determined. We believe that the combination of SALDI-MS and MTF-AuNP sample substrates would be a potential approach for bone biomarker detection in the osteoporosis risk assessment.

The migration pathway of potassium in biomass during coal/biomass co-gasification was studied both qualitatively and quantitatively. A reactor was employed to individually perform pyrolysis and gasification of two raw materials and their blends. An inductively coupled plasma mass spectrometry accurately measured the amount and occurrence of potassium in biomass migration. Results showed that about 58.6 wt% potassium in biomass existed in the water-soluble form. When the blends were pyrolyzed at above 500 °C, about 65.0 wt% potassium in biomass migrated to the coal char, 19.1 wt% potassium in biomass remained in the biomass char and 15.9 wt% potassium in gas phase. The migrated potassium salt in coal char still existed as a 75.4 wt% insoluble sulfate. Reaction temperature and the ratio of Al to Si from the minerals in coal are key issues for the redistribution of potassium in biomass. The water-soluble potassium in biomass helps to catalytic co-gasification.

Simulated drinking water distribution system (DWDS) treated with O 3 -BAC-Cl 2 (ozone-biological activated carbon-chlorine) was constructed to study its effects on the regrowth of five typical opportunistic pathogens (OPs). It was found that O 3 -BAC-Cl 2 could significantly reduce the regrowth of target OPs in the effluents of DWDS compared with Cl 2 and O 3 -Cl 2 with the same residual chlorine levels. However, the effect of O 3 -BAC-Cl 2 on the average numbers of target OPs gene markers in the biofilms of DWDS was not apparent, suggesting that OPs in the biofilms of DWDS were tolerant to the upstream disinfection process. The quantification of target OPs in the BAC-filter column demonstrated that OPs decreased with the increase of depth, which was likely due to the organic nutrient gradient and microbial competition inside the BAC-filter. Increase in the ozone dose could further reduce the OPs at the bottom of the BAC-filter. Spearman correlation analysis demonstrated that some significant correlations existed between target microorganisms, suggesting potential microbial ecological relationships. Overall, our results demonstrated that the BAC-filter may act as a “battlefield” suppressing the OPs through microbial competition. O 3 -BAC-Cl 2 could be an effective multi-barrier process to suppress the proliferation of OPs in the bulk water of DWDS. However, OPs protected by the biofilms of DWDS should receive further attention because OPs may be detached and released from the biofilms.

This paper proposes a multipurpose reinforcement learning based low-level multirotor unmanned aerial vehicles control structure constructed using neural networks with model-free training. Other low-level reinforcement learning controllers developed in studies have only been applicable to a model-specific and physical-parameter-specific multirotor, and time-consuming training is required when switching to a different vehicle. We use a 6-degree-of-freedom dynamic model combining acceleration-based control from the policy neural network to overcome these problems. The UAV automatically learns the maneuver by an end-to-end neural network from fusion states to acceleration command. The state estimation is performed using the data from on-board sensors and motion capture. The motion capture system provides spatial position information and a multisensory fusion framework fuses the measurement from the onboard inertia measurement units for compensating the time delay and low update frequency of the capture system. Without requiring expert demonstration, the trained control policy implemented using an improved algorithm can be applied to various multirotors with the output directly mapped to actuators. The algorithm’s ability to control multirotors in the hovering and the tracking task is evaluated. Through simulation and actual experiments, we demonstrate the flight control with a quadrotor and hexrotor by using the trained policy. With the same policy, we verify that we can stabilize the quadrotor and hexrotor in the air under random initial states.

Introducing olfactory display in the virtual reality (VR) system brings the immersive experience to new heights. However, it is intractable to simulate olfactory features (such as the intensity and the direction) with multiple levels. Visual stimuli have been proved to dominate human perception among multiple sensors in virtual environments. If visual stimuli can be used to guide the olfactory sense in VR, the design of the olfactory display can be simpler but still able to provide olfactory experience with more diversity. To understand the visual-olfactory effect on different olfactory characteristics, a portable olfactory display that can control the intensity and direction of odors was developed. An experimental study was conducted to investigate cross-modal human perception, i.e. how the visually virtual odor representation in VR influences human perception of real odor produced by the proposed olfactory display. The results showed that the perception of odor intensity and directionality can be modulated by visually virtual odor representation.

In the present article, we report a novel colorimetric probe (TNT@MB) for the detection of the phosphate ion, which is based on the strong binding affinity between the phosphate ion and titanium dioxide nanotubes (TNTs). TNTs were synthesized from TiO2 nanoparticles by hydrothermal treatment. The obtained TNTs had an average length of 200 ± 50 nm and an average width of 12 ± 5 nm. TNT@MB was prepared by adsorbing methyl blue onto TNTs in acidic condition. The optimal synthesis conditions for TNT@MB consisted in having 0.05 g of TNTs react with 1 μmole of methyl blue at pH 2 for 90 min. TNTs and TNT@MB were characterized by UV–vis diffuse reflection spectroscopy, TEM, FTIR, and XPS. The phosphate-ion sensing behavior of TNT@MB was investigated by UV–visible spectroscopy. The phosphate-ion concentration linear range and detection limit of this method based on TNT@MB were 1–40 μM and 0.59 μM, respectively. A sample of lake water was used as a real sample, and analyte recovery rates were measured in the 102.5–103.6% range, with relative standard deviations below 5.6% (n = 3). We also found that this probe could be reused after regeneration in alkaline solution. These results indicate that as a colorimetric probe, TNT@MB has the advantages of being environmentally friendly, inexpensive, and simple to use, as well as giving rise to an easily observable color change.

Abnormal event detection in surveillance videos refers to the identification of events that deviate from the normal pattern. An autoencoder can be used to learn the normal patterns from the videos, and its reconstruction errors can be used to detect the abnormalities. Surveillance videos consist of two components: dynamic objects and a static background. Because of the nature of the static background, we can assume that the source of abnormality is from the objects. In this work, we propose the use of a two-stream decoder model to tackle the abnormal event detection problem in surveillance videos. The two-stream decoder comprised a background stream that models the static background and a foreground stream that models the dynamic objects. We also utilized a two-stream encoder to learn from optical flow, which contains motion information, and skip connections used to improve the details in the output frames. Several experiments on publicly available datasets were used to validate the effectiveness of the proposed model.

The influence of blanking speed on the blanked surface quality of C5191 bronze phosphorus sheets, with a thickness of 0.12 mm, was systematically studied to demonstrate the mechanism under high speed blanking. The morphology and microstructure of the blanked edge were observed by using a variety of techniques, including optical microscopy (OM), scanning electron microscope (SEM), electron backscatter diffraction (EBSD), and transmission electron microscope (TEM). The results revealed that the local temperature and microhardness of the shear zone increased with the increase in blanking speed. Moreover, the quality of blanked edge significantly improved with the increase in blanking speed due to the combined influence of strain rate hardening and thermal softening. In addition, the blanked edge grains were elongated along the blanking direction and formed dislocation cells and sub-grains in some areas. The blanked edge is dominated by {000} &lt, 100&gt, cubic texture at higher blanking speeds, and {112} &lt, 111&gt, texture at lower blanking speeds. When punched at an ultra-high speed of 3000 strokes per minute (SPM 3000), the local area of the blanked edge exhibited distinct microstructural features, including low dislocation density, nanocrystals with high-angle grain boundaries, and significant differences in grain orientation. Additionally, the selected area electron diffraction (SAED) pattern exhibited a discontinuous ring-like structure, indicating the occurrence of adiabatic shearing with dynamic recrystallization.

Emotion reacts human beings' physiological and psychological status. Galvanic Skin Response (GSR) can reveal the electrical characteristics of human skin and is widely used to recognize the presence of emotion. In this work, we propose an emotion recognition frame-work based on deep hybrid neural networks, in which 1D CNN and Residual Bidirectional GRU are employed for time series data analysis. The experimental results show that the proposed method can outperform other state-of-the-art methods. In addition, we port the proposed emotion recognition model on Raspberry Pi and design a real-time emotion interaction robot to verify the efficiency of this work.

The development of an efficient electrocatalyst toward the hydrogen evolution reaction (HER) is of significant importance in transforming renewable electricity to pure and clean hydrogen by water splitting. However, the construction of an active electrocatalyst with multiple sites that can promote the dissociation of water molecules still remains a great challenge. Herein, a partial‐single‐atom, partial‐nanoparticle composite consisting of nanosized ruthenium (Ru) nanoparticles (NPs) and individual Ru atoms as an energy‐efficient HER catalyst in alkaline medium is reported. The formation of this unique composite mainly results from the dispersion of Ru NPs to small‐size NPs and single atoms (SAs) on the Fe/N codoped carbon (Fe–N–C) substrate due to the thermodynamic stability. The optimal catalyst exhibits an outstanding HER activity with an ultralow overpotential (9 mV) at 10 mA cm−2 (η 10), a high turnover frequency (8.9 H2 s−1 at 50 mV overpotential), and nearly 100% Faraday efficiency, outperforming the state‐of‐the‐art commercial Pt/C and other reported HER electrocatalysts in alkaline condition. Both experimental and theoretical calculations reveal that the coexistence of Ru NPs and SAs can improve the hydride coupling and water dissociation kinetics, thus synergistically enhancing alkaline hydrogen evolution performance., A nanocomposite of partial‐single‐atom and partial‐nanoparticle formed within the Fe–N–C matrix serves as a multiple‐site electrocatalyst toward hydrogen evolution reaction with an ultralow overpotential of 9 mV to achieve 10 mA cm−2, a high turnover frequency, and ≈100% Faradaic efficiency. Theoretical calculations reveal that ruthenium single‐atoms effectively facilitate water dissociation, and ruthenium nanoparticles promote hydrogen desorption.

A number of applications in next-generation multi-hop networks impose low-latency requirements on data transmission thereby necessitating the underlying relays to introduce negligible delay when forwarding the packets. While traditional relaying techniques such as amplify-and-forward may help the packets to satisfy latency-constraints, such strategies do not facilitate the destination in determining security threats, if any, during the packet’s journey. Inspired by the problem of relaying packets that have low-latency constraints, we revisit the design of provenance embedding algorithms to reduce delays on the packets and yet assist the destination in determining the provenance with no knowledge on the network topology. We propose a new class of provenance embedding techniques, referred to as double-edge (DE) embedding techniques, wherein a subset of the relay nodes in the path strategically skip the provenance embedding process to reduce the delays on the packets. Under the framework of DE embedding techniques, we propose a deterministic skipping strategy among the nodes such that the destination can recover the provenance of every packet. Using fixed-size bloom filters as tools to implement the double-edge embedding ideas, we propose upper bounds on the error-rates of the DE embedding technique as a function of the number of nodes in the network, number of hops, bloom filter size, and the number of hash functions used by each node. Subsequently, we demonstrate the efficacy of the DE embedding technique on a testbed of Digi XBee devices, and show that it outperforms competitive baselines both in terms of latency as well as error-rates.

Cell-aware test (CAT) explicitly targets faults caused by cell-internal short and open defects and has been shown to significantly reduce test escape rates. CAT library cell characterization is typically done for only two defect resistance values: one representing hard opens and another one representing hard shorts. In this paper, similar to fishermen tightening the mesh size of their nets to catch small fish, we perform library characterization as efficiently as possible for a set of resistances representing increasingly weaker defects, and then adjust our ATPG flow to explicitly target faults caused by the weakest still-detectable variant of each potential defect. We implemented this novel approach in an experimental ATPG tool flow script, using functions of Cadence's Modus as building blocks. To assess the effectiveness of our approach, we formulate a new dedicated test metric: the weakest fault coverage wfc. Compared to conventional CAT targeting hard defects only, experimental results show that our new approach enhances detection of weakest faults and significantly reduces wfc escapes =1-wfc, while maintaining its original (hard-defect) fault coverage fc, of course at the expense of (acceptable) increases in the required number of test patterns and associated test generation time.