One of the challenges to realize large‐scale water splitting is the lack of active and low‐cost electrocatalysts for its two half reactions: H2 and O2 evolution reactions (HER and OER). Herein, we ...report that cobalt‐phosphorous‐derived films (Co‐P) can act as bifunctional catalysts for overall water splitting. The as‐prepared Co‐P films exhibited remarkable catalytic performance for both HER and OER in alkaline media, with a current density of 10 mA cm−2 at overpotentials of −94 mV for HER and 345 mV for OER and Tafel slopes of 42 and 47 mV/dec, respectively. They can be employed as catalysts on both anode and cathode for overall water splitting with 100 % Faradaic efficiency, rivalling the integrated performance of Pt and IrO2. The major composition of the as‐prepared and post‐HER films are metallic cobalt and cobalt phosphide, which partially evolved to cobalt oxide during OER.
Split and polished: Electrodeposited cobalt‐phosphorous‐derived films (Co‐P) can act as superior bifunctional catalysts for overall water splitting. When employed as catalysts on both the anode and cathode for water electrolysis, the Co‐P/Co‐P catalyst couple can rival the integrated performance of IrO2 and Pt in alkaline media. Such a bifunctional Co‐P film is a promising catalyst candidate for overall water‐splitting electrolysis.
•Damage by the induced electric field in the TEM is thoroughly analyzed.•Damage is caused by atom migration driven by the induced electric field.•The electric field is produced by trapped positive ...charges on surfaces due to electron emissions.•The field is strong at the surface region and near the periphery of the illumination.•In the wedge-shaped specimen, the field is strong at the edge of the specimen.
Electric fields can be induced by electron irradiation of insulating thin film materials. In this work, the electric fields under a broad beam illumination in transmission electron microscopy (TEM) are analyzed for insulating samples. Some damage phenomena observed can be interpreted by the mechanism of damage by the induced electric field (DIEF). For broad-beam illumination in an ultra-thin specimen, the electric field near the center of the illumination may not be strong, but at the periphery of the illumination the electric field can be significant. Therefore, damage may be easily observed in these regions rather than at the center of the illumination. For a beam which is broad compared to the specimen thickness, e.g. 100∼1000nm, a strong electric field pointing inward into the specimen near the surface region may result in cation diffusion into the specimen and/or anion diffusion out to the surface region. Meanwhile, a strong electric field perpendicular to the beam direction near the edge of the illumination may attract anions into the illuminated region, but eject cations to the periphery. For a wedge-shaped specimen, the electric field points inward into thicker region, driving cations toward the thicker region, while attracting anions to the edge region. On the sharp edge, a strong electric field pointing outward may be responsible for the edge-smoothing effect observed in insulating materials.
In order to develop an appropriate method for high-throughput detection of avian metapneumovirus, a quadruple real-time reverse-transcription polymerase chain reaction assay was established with four ...pairs of specific primers and four specific probes based on the G or M gene of aMPV-A, aMPV-B, aMPV-C and aMPV-D. Its specificity and sensitivity were evaluated, and clinical samples were tested by the method. The results showed that all the four subgroups of avian metapneumovirus can be detected in the quadruple real-time RT-PCR assay simultaneously, with a detection limit of 100-1000 cRNA copies/reaction. The other common poultry viruses were negative. In the avian clinical sample detection, 39 out of 1920 clinical samples collected from 8 provinces were positive. Compared with published RT-PCR assays, the kappa value of the quadruple real-time RT-PCR assay in 1920 avian clinical samples was 1.000 (P < 0.001). The established method could be used for the rapid detection of the four subgroups of avian metapneumovirus with high specificity and high sensitivity.
We investigate how disagreement in natural language inference (NLI) annotation
arises. We developed a taxonomy of disagreement sources with 10 categories
spanning 3 high- level classes. We found that ...some disagreements are due to
uncertainty in the sentence meaning, others to annotator biases and task
artifacts, leading to different interpretations of the label distribution. We
explore two modeling approaches for detecting items with potential disagreement:
a 4-way classification with a “Complicated” label in addition to
the three standard NLI labels, and a multilabel classification approach. We
found that the multilabel classification is more expressive and gives better
recall of the possible interpretations in the data.
This study examined the development of integrated knowledge or automatic competence in adult SLA. Automatic competence was operationalized in terms of the participants' sensitivity to grammatical ...errors in a self‐paced reading task. Their sensitivity was determined by observing whether there was a delay in reading ungrammatical sentences. Native and nonnative speakers of English read grammatical and ungrammatical sentences that contained errors involving plural –s and verb subcategorization. Their reading times were measured and compared. The results showed that native speakers were sensitive to errors involving both structures, but nonnative speakers were only sensitive to errors involving verb subcategorization. The results confirmed that the development of second language automatic competence or integrated knowledge is selective. Alternative explanations of this selectivity are discussed.
Orthopaedic disorders, also known as musculoskeletal disorders (MSDs), refer to diseases or injuries of the bone, joint, cartilage, muscle, tendon, nerve, and spinal disc ...
At present, preschool education has been included in China's compulsory education and has become an important part of China's basic education. With the continuous development of information ...technology, kindergartens in some coastal areas have begun to apply artificial intelligence technology to the daily teaching. The use of artificial intelligence technology for teaching can not only improve children's enthusiasm for learning but also help the reform of preschool education institutions. In view of this, the article mainly analyzes the application of artificial intelligence technology in preschool education, and proposes corresponding solutions to the problems in artificial intelligence education and teaching.
In this study, we use an extension of Yang’s convergence criterion N. Jiang, On the wavewise entropy inequality for high-resolution schemes with source terms II: the fully discrete case to show the ...entropy convergence of a class of fully discrete α schemes, now with source terms, for non-homogeneous scalar convex conservation laws in the one-dimensional case. The homogeneous counterparts (HCPs) of these schemes were constructed by S. Osher and S. Chakravarthy in the mid-1980s A New Class of High Accuracy TVD Schemes for Hyperbolic Conservation Laws (1985), Very High Order Accurate TVD Schemes (1986), and the entropy convergence of these methods, when m=2, was settled by the author N. Jiang, The Convergence of α Schemes for Conservation Laws II: Fully-Discrete. For semi-discrete α schemes, with or without source terms, the entropy convergence of these schemes was previously established (for m=2) by the author N. Jiang, The Convergence of α Schemes for Conservation Laws I: Semi-Discrete Case.
A low noise laser system for atom interferometry is realized with phase-locked fiber lasers, where the performance of the OPLL is greatly enhanced by the FEOM feedback loop and the narrow linewidths. ...The laser system demonstrated contribute 2.2 mrad per shot to the interferometer noise and permit continuous long-term operation for more than 115 h without relocking in the field test. Also, the mobile gravimeter equipped with this phase-locked laser system reaches a sensitivity as good as 29
μ
Gal
/
Hz
and a resolution of 1.1
μ
Gal
within 1500 s, demonstrating performances comparable to the state of the art.
Massive Internet of Things (mIoT) has provided an auspicious opportunity to build powerful and ubiquitous connections that face a plethora of new challenges, where cellular networks are potential ...solutions due to their high scalability, reliability, and efficiency. The random access channel (RACH) procedure is the first step of connection establishment between IoT devices and base stations in the cellular-based mIoT network, where modeling the interactions between static properties of the physical layer network and dynamic properties of queue evolving in each IoT device are challenging. To tackle this, we provide a novel traffic-aware spatio-temporal model to analyze RACH in cellular-based mIoT networks, where the physical layer network is modeled and analyzed based on stochastic geometry in the spatial domain, and the queue evolution is analyzed based on probability theory in the time domain. For performance evaluation, we derive the exact expressions for the preamble transmission success probabilities of a randomly chosen IoT device with different RACH schemes in each time slot, which offer insights into the effectiveness of each RACH scheme. Our derived analytical results are verified by the realistic simulations capturing the evolution of packets in each IoT device. This mathematical model and the analytical framework can be applied to evaluate the performance of other types of RACH schemes in the cellular-based networks by simply integrating its preamble transmission principle.
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