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Work zones which are usually referred to as traffic bottlenecks or critical points may lead to reductions in both operational performance and safety. Researchers have conducted extensive studies on speed characteristics in freeway work zones. However, most of these studies are based on simulation data or are travel direction-based rather than lane- based. By utilizing the video recording capability of drones, this paper aims to provide methodologies and the workflow in exploring the vehicular speed characteristics in freeway work zones with considerations for lane and location deviations. A four-to-three lane work zone on Huhang Expressway between Downtown Shanghai and Songjiang in China was selected for data collection. Then free flow speed variation pattern is analyzed, a speed prediction model is proposed, and the speed-flow relationship is investigated on each lane at nine virtual sections along the work zone. It is found that the merging area affects the speeds mainly in the segment from 200 m upstream of the taper to the start of the activity area, which is the most important risk area in the work zone, and the speed characteristics depend on vehicle types (trucks versus automobiles) as well as lane locations. It is also showed that drones are valuable and effective tools for data collection for vehicular speed characteristics analysis in freeway work zones and it is easy to extract the information needed. Key words: work zone, speed characteristics, lane-based, multiple sections, aerial video. Les zones de travail que l'on appelle habituellement des goulots d'etranglement ou des points critiques peuvent entrainer des reductions de la performance operationnelle et de la securite. Les chercheurs ont mene des etudes approfondies sur les caracteristiques de vitesse dans les zones de travail sur les autoroutes. Cependant, la plupart de ces etudes sont fondees sur des donnees de simulation ou reposent sur la direction des deplacements plutot que sur les voies. Grace a l'utilisation des capacites d'enregistrement video d'un drone, ce document vise a fournir des methodologies et le flux de travaux dans l'exploration des caracteristiques de vitesse des vehicules dans les zones de travail d'autoroute avec des considerations pour les ecarts de voies et de position. Une zone de travail de quatre a trois voies sur l'autoroute Huhang entre le centreville de Shanghai et Songjiang en Chine a ete choisie pour la collecte de donnees. On analyse ensuite le modele de variation de vitesse d'ecoulement libre, on propose un modele de prevision de la vitesse et on etudie la relation vitesse-debit sur chaque voie a neuf sections virtuelles le long de la zone de travail. Il est constate que la zone d'ecoulement convergent affecte les vitesses principalement dans le segment a partir de 200 m en amont du biseau jusqu'au debut de la zone d'activite qui est la zone de risque la plus importante dans la zone de travail et les caracteristiques de vitesse dependent des types de vehicules (camions versus automobiles) ainsi que de l'emplacement des voies. Il est egalement montre que les drones sont des outils pratiques et efficaces pour la collecte de donnees aux fins d'analyse des caracteristiques de vitesse des vehicules dans les zones de travail sur les autoroutes et il est facile d'extraire les informations necessaires. Mots-cles: zone de travail, caracteristiques de vitesse, selon les voies, plusieurs sections, video aerienne., Introduction As traffic demand is growing at a much faster rate than the infrastructure to accommodate it, more roadway improvements are needed. Work zones for maintenance and reconstruction of existing [...]

For electrocatalytic processes, the electronic structure especially the density of states (DOS) of electrode materials plays a dominant role in process of electron transfer kinetics for redox reactions. The unusual electronic properties of sp2‐hybridized carbon nanomaterials with adjustable DOS offer great promise in constructing high performance electrodes for electrochemical applications. However, researchers are still confronted with challenges such as how the electronic properties influence the kinetics of electron transfer and how to modulate the electronic structure appropriate strategy for achieving efficient electrochemical reactions of different sp2 carbon nanomaterials. With the aim of understanding the impacts of electronic structures on electrocatalytic properties, we selected several typical 0D to 3D carbon nanomaterials, and tailored the electrocatalytic performance of carbon nanomaterials by doping electron donor and electron acceptor. The results demonstrate that different molecular doping give rise to entirely different modifications in electronic structure of the sp2‐hybridized carbon nanomaterials, endowing modulation of the electrocatalytic properties for the appropriate redox reaction. When doped with electron acceptor, it is more conducive to the oxidation reaction. Conversely, doping with electron donors is more conducive to the occurrence of reduction reactions. This strategy reveals electronic structure effects on the electron transfer of electrocatalytic redox reaction and provides an efficient approach on tailoring the electrocatalytic performance of sp2‐hybridized carbon nanomaterials. For further electrochemical applications, that can ultimately provide rational guidance toward the development of improved catalysts. [ABSTRACT FROM AUTHOR]

The porous microspherical Nitrogen and Phosphorus‐co‐doped NiFe2O4/Single‐Walled Carbon Nanotubes (NP‐NiFe2O4/SWNTs) had been fabricated. Nitrogen (N) and phosphorous (P) were co‐doped to increase the active sites. And SWNTs hybrid was to obtain the enhanced conductivity, large specific surface area and more active sites. The hierarchical, porous structure and highly conductive SWNTs enables efficient transport of the electrons generated during oxygen evolution reaction (OER). Thus, NP‐NiFe2O4/SWNTs was demonstrated as a high‐performance catalyst for OER with a small overpotential of 247 mV at 10 mA cm−2 and low Tafel slope of 83.6 mV dec−1. The outstanding performance of NP‐NiFe2O4/SWNTs can also made it serve as anode for water splitting at a cell voltage of 1.595 V, which surpasses the precious RuO2 and Pt/C. That's dope! Porous microspherical nitrogen and phosphorus‐co‐doped NiFe2O4/single‐walled carbon nanotubes have been developed for efficient oxygen evolution reaction, which showed the strategy to improve the catalytic activity by designing and tuning the hierarchical structure, composition, conductivity and active sites. [ABSTRACT FROM AUTHOR]

Although there are various advancements in biomedical in the past few decades, there are still challenges in the treatment of brain diseases. The main difficulties are the inability to deliver a therapeutic dose of the drug to the brain through the blood‐brain barrier (BBB) and the serious side effects of the drug. Thus, it is essential to select biocompatible drug carriers and novel therapeutic tools to better enhance the effect of brain disease treatment. In recent years, biomimetic nanoparticles (BNPs) based on natural cell membranes, which have excellent biocompatibility and low immunogenicity, are widely used in the treatment of brain diseases to enable the drug to successfully cross the BBB and target brain lesions. BNPs can prolong the circulation time in vivo, are more conducive to drug aggregation in brain lesions. Cell membranes (CMs) from cancer cells (CCs), red blood cells (RBCs), white blood cells (WBCs), and so on are used as biomimetic coatings for nanoparticles (NPs) to achieve the ability to target, evade clearance, or stimulate the immune system. This review summarizes the application of different cell sources as BNPs coatings in the treatment of brain diseases and discusses the possibilities and challenges of clinical translation. [ABSTRACT FROM AUTHOR]

An electrodeposition method for fabrication of CuTe and Cu2Te thin films is presented. The films’ growth is based on the epitaxial electrodeposition of Cu and Te alternately with different electrochemical parameter, respectively. The deposited thin films were characterized by X-ray diffraction (XRD), field emission scanning electronic microscopy (FE-SEM) with an energy dispersive X-ray (EDX) analyzer, and FTIR studies. The results suggest that the epitaxial electrodeposition is an ideal method for deposition of compound semiconductor films for photoelectric applications. [ABSTRACT FROM AUTHOR]

An electrochemical sensor for selective detection of ascorbic acid (AA) in the presence of dopamine (DA) and uric acid (UA) was fabricated by modifying the glassy carbon electrode (GCE) with carbon-supported NiCoO2 (NiCoO2/C) nanoparticles. The electrochemical impedance spectroscopic (EIS) studies reveal the little charge transfer resistance for the modified electrode. The electrocatalytic activity of the modified electrode for the oxidation of AA was investigated. The current sensitivity of AA was enhanced to about five times upon modification. The voltammetric response of AA was well resolved from the responses of DA and UA, and the oxidation potential of AA was negatively shifted to −0.20V. The biosensor tolerated a wide linear concentration range for AA, from 1.0×10−5 M to 2.63×10−3 M (R 2=0.9929), with a detection limit of 0.5μM (S/N=3). Our results demonstrate that the NiCoO2/C nanomaterials has excellent AA sensing capability, including a fast response time, high reproducibility and stability, with great promise in the quantification of AA in real samples. That makes it a unique electrochemical sensor for the detection of AA which is free from the interference of DA, UA and other interferents. [ABSTRACT FROM AUTHOR]