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Morphology profoundly influences nanomaterials' performance for various applications including energy, environment, and catalysis etc. Molybdenum disulfide, the most studied nanomaterial after graphene, has undergone intense research in this perspective, showing its potential for real-time applicability. The unique electronic structure and charge distribution make MoS 2 suitable for practicing various faceted controlled synthesis methods and exploring apposite application paths for each topographical structure. The most popular topographical structures include nanosheets, nanoflowers, nanoscrolls, nanoribbons, nanowires, wrinkled structures, nanotubes, nanospheres, and hierarchical structures. The present review presents a comprehensive collection of advents in specific morphology targeted synthesis of MoS 2 and the contribution of each morphology towards specific applications. [Display omitted] • Summarized the impact of morphology on the properties of morphologically diverse MoS 2 in various applications. • Summarized the importance of popular topological forms of MoS 2 in connection with specific high-end applications. • Discussed the direct influence of MoS 2 nanostructure morphologies ranging from 1D to 3D on their high-end applications. • Detailed the role of the morphology of MoS 2 nanostructures in applications ranging from environment to energy. • Shared the perspective on the challenges and opportunities of the morphology engineering design of MoS 2. [ABSTRACT FROM AUTHOR]

Bone was a crucial biological material for the evolution of large terrestrial organisms and is today essential for most of our daily activities and well-being. From an engineering perspective, this living material features highly desirable properties for modern load-bearing structures. It is made of abundant and environmental-friendly building blocks, which are combined into a tough and durable structure that can continuously modify itself to adapt to changes in the mechanical load imposed by the surroundings. In this review article, we compile and discuss scientific findings that allow us to understand bone as a complex system with properties that emerge from cell-mediated interactions of molecules and particles at multiple length scales. Analogous to other complex systems, such interactions lead to self-organization, hierarchical structures and adaptive behavior without the need of a central controlling unit. A rich range of physical, chemical and biological phenomena provide a framework for information to be generated and processed in this complex system. Understanding the interplay between such underlying phenomena and their emerging properties should help the diagnosis and treatment of bone-related medical conditions and might provide guidelines for the future development of more sustainable materials and engineering structures. [ABSTRACT FROM AUTHOR]

In recent years, fabrication of varied topographies, hierarchical structures and multiscale textures has attracted the research interest. Single step fabrication of hierarchical structures at sub-mm or microscale still remains a challenge for machining processes. In this work, a novel tool based hybrid laser-electrochemical micromachining process is presented which combines laser and electrochemical process energies on same machining axis by means of a hybrid tool. The hybrid tool acts as both an ECM tool and a multimode waveguide for the laser. With this technology, generation of uniform dual-scale surface structures is realized in single step. These structures have a dual-scale hierarchical morphology. Array of hierarchical cavities have been fabricated by this process on Inconel IN718 using a 1.2 mm diameter tool. Process details have been presented and machined hierarchical cavities are analyzed. It is shown that by controlling the process parameters of both laser and ECM, the geometry and structure of these hierarchical cavities can be controlled. Overall, it is shown that the hybrid laser-electrochemical micromachining technology facilitates fabrication of hierarchical surface structures due to application of different process energies at different scales. Further scaling down of the features is possible with scaling down of hybrid tool dimensions using state of the art microfabrication techniques. [ABSTRACT FROM AUTHOR]

Functional surfaces have been investigated widely due to different applications in industries. In this paper, the surface functionality was the contrast generated by surfaces orthogonally textured with micro ridges. The principle to generate contrast was the anisotropic reflection led by the bevel surfaces of micro ridges. The surface quality of the micro bevels determined the reflection of the features. In the authors' previous work, such a functionality was successfully achieved on flat and cylinder surfaces of tool steel samples by micro milling. However, due to the limitation of micro milling process for microstructure fabrication, this study investigated the manufacturing of 3D functional surfaces of RSA 905 by diamond engraving. The 3D surface was shaped with hierarchical structures of micro bricks and micro ridges on the bricks: the surface was divided into micro grids then each grid was machined into a flat basic cell by using a round-tipped tool; the micro ridges were engraved on the basic cells with a sharp-tipped tool. In order to determine the feasibility of the microstructures to achieve contrast generation on 3D surfaces, a data matrix consisting of such micro ridges was patterned on a spherical concave and a freeform surface. The surface integrity was evaluated by measuring the surface roughness of the bevels on the micro ridges, characterizing the burr formation and detection of possible defects left on the micro features that affect the surface functionality. The successful scanning of the data matrix proved the microstructures successfully generated enough contrast to form readable codes. Furthermore, the contrast generated by the microstructures was quantified for process optimization by using a customized robotic measuring system. [ABSTRACT FROM AUTHOR]

Developing advanced sorbents for selective carbon dioxide (CO 2) sequestration with minimal energy consumption remains a pivotal challenge. This study presents a novel strategy through transforming 3D bulk zirconium-porphyrin frameworks into the corresponding 2D nanosheet-assembled superstructures for enhanced CO 2 capture. The hierarchical frameworks with well-organized nanosheet architectures exhibit significantly increased specific surface area from 600 m2/g to 2400 m2/g while providing kinetic benefits for gas diffusion. Compared to the adsorption behavior of the bulk counterparts, the nanosheet-assembled frameworks demonstrate a 1.5-fold increase in CO 2 adsorption capacity without compromising CO 2 /N 2 selectivity. Theoretical calculation reveals that the coordination unsaturated Zr-O clusters, electron delocalized environments both in interlayer gaps and micropores provided binding sites for CO 2 capture. Our research demonstrates an adaptable structure-directed approach for the crystal engineering of metal-organic frameworks which would inspire the creation of state-of-the-art crystalline porous materials for broadened applications. [Display omitted] Transforming 3D zirconium-porphyrin frameworks into 2D nanosheet-assembled superstructures enabling enhanced CO 2 adsorption capacity while providing kinetic benefits in gas diffusion. The 2D superstructures exhibited increased CO 2 adsorption capacity by 2.5 times compared to the bulk counterparts without sacrificing the CO 2 /N 2 selectivity. • A strategy to fabricate nanosheet-assembled zirconium-porphyrin superstructures. • Significantly increased specific surface area up to 2400 m2/g. • Enhanced CO 2 capture ability without compromising CO 2 /N 2 selectivity. • Theoretical calculation revealing the CO 2 adsorption mechanism. [ABSTRACT FROM AUTHOR]

Efficient touch feedback, capable of monitoring the magnitude of force and identifying active location, is significant to artificial intelligence and interactive robotics. It generally needs the integration of multitudinous sensing elements and intricate manufacturing procedures. Here we propose a multifunctional paper-based touch sensor to realize touch trajectory recognition as well as achieve pressure information. The asymmetric and symmetric structures are designed to skillfully construct localization layer and pressure sensing layer. These functional layers effectively assemble a scalable touch sensor and, thus, greatly simplify the device's architecture with the competitive advantages of easiness in fabrication, cost-effectiveness, self-switching characteristic, and programmability in interactive function. Through coding and using the electrical signals, human-computer interaction, human-machine interaction, and force-enhanced cryptographic matrix are explored and demonstrate the feasibility of the proposed touch sensor. This work provides a novel mechanosensational sensing paradigm to leverage the complex physics of a feasible strategy for advancing human-related interactive electronics. Image 1 • The touch sensor based on synergistic sensing of stratified structures can identify touch track and detect pressure signal. • Design of hierarchically symmetric and asymmetric structures enables to greatly simplify the architecture of touch sensor. • Touch sensor constructed on paper substrate features low cost, portability, and environmental friendliness. • Multifarious human-related interactions demonstrate the programmability and potential of the proposed touch sensor. [ABSTRACT FROM AUTHOR]

Fundamental research into electrode materials has focussed on their active area and catalytic ability to drive reaction kinetics. Prerequisites for practical electrodes used in industrial processing and technology include moderate costs, good mechanical, thermal and chemical stability, effective electrocatalysis, a high electrical conductivity and the facility for scale-up, such that an electrochemical engineering approach is important. Following a consideration of important electrode properties, this concise review considers the fabrication, imaging, structure and the dressing of electrode surfaces with particles, coatings and films; nanostructured and hierarchical features are included. Trends in electrodes are noted, using examples from the author's laboratory. Electrochemical surface finishing techniques make an important contribution to the toolbox of practical techniques capable of industrial development. Approaches to electrode fabrication and surface finishing are considered in application areas such as energy storage and conversion, environmental treatment and tribology. [ABSTRACT FROM AUTHOR]

A fundamental challenge of photocatalysis is developing efficient strategies to suppress the recombination of photogenerated charge carriers. Herein, ZnO/BiVO 4 hierarchical nanostructures were exemplified to demonstrate new concept of multi-electric field-assisted charge separation. The contribution of both facet engineering and defect modulation to the facilitated photocatalysis was confirmed by both experimental observations and theoretical calculations. Such integration of built-in fields in faceted BiVO 4 and anisotropic ZnO nanorods, together with the possible Z-scheme at the interfaces resulted into 1.36 mmol h −1 g −1 O 2 produced under visible light irradiation, and more than one order of magnitude enhanced apparent quantum yield at 450 nm. This work not only provides fundamental insights into the facet-dependent distribution of interfacial defects, but also offers a strategy for the design of faceted heterojunctions with controlled vacancies for significantly enhanced charge separation. [ABSTRACT FROM AUTHOR]

Ni 3 Se 2 nanoforest has been successfully grown on Ni foam via a facile one-step and cost-effective solution-chemical route. This handy strategy endues the product with three characteristics: metallic Ni 3 Se 2 , hydrophilic and aerophobic surface, as well as self-support on highly conductive substrate. The as-synthesized Ni 3 Se 2 nanoforest/Ni foam shows excellent electrocatalytic activity and stability for both HER and OER. [ABSTRACT FROM AUTHOR]

Gas sensing performances of SnO2can often be improved remarkably once the thickness of nanosheets shrinks to a critical value of 14 nm (2λD) or self-assembly of two-dimensional nanoscale building blocks into three-dimensional (3D) complex superstructures. Here, using the hydrothermal method, we synthesise the SnO23D hierarchical nanostructures assembled with ultrathin nanosheets with a thickness as thin as 9–12 nm by adding sodium oxalate (Na2C2O4). Wondrously, using oxalic and sodium hydroxide (H2C2O4+2NaOH) substitute for equimolar Na2C2O4, the dimensions of nanosheets decrease, which may be due to the active degree is different between the Na2C2O4directly and indirectly obtained by H2C2O4. In property, the as prepared SnO2hierarchical nanostructures display excellent gas sensing functions to ethanol gas due to their subsize and the plane to plane contacts. [ABSTRACT FROM AUTHOR]

The incorporation of heteroatoms into carbon nanomaterials is extremely crucial for tuning their electronic and surface properties, but phosphorus (P) incorporation into hierarchical structure remains challenging and its charge storage mechanism is obscure. Herein, we investigate surface redox charge storage of hierarchically structured, P-incorporated graphene architectures (hpGAs). As probed by in-situ and ex-situ spectroscopic techniques and density functional theory, the P=O site of C–P=O bonding with the most favorable proton binding energy is identified and associated with highly reversible and fast pseudocapacitive behavior. As a consequence of synergistic effects arising from compositional and structural features, the hpGAs show dramatic improvements in capacitance, rate capability, and cyclic stability. This work broadens our knowledge about the unique surface charge storage phenomenon originating from the controlled heteroatom chemistry using combined spectroscopic and computational methods. [ABSTRACT FROM AUTHOR]

ZnO hierarchical structure has been synthesis by using chemical routs method. Hydra zinc nitrate, oleic acid, ethanol was used as row materials for the chemical reaction in the presence of NaOH. The Reaction took place at room temperature under stirrer. The prepared ZnO powder is collected and mixed with PVA to make a proper paste, then the paste was screen-printed in 1cm square pattern to make thick films. Afterwards, the films are annealed at 500 C˚ for an hour. The morphology, crystallinity and structural properties are studied by X-ray diffraction, the experimental pattern of the films show very fine peaks indicate a good crystallization, also the morphology of the films studied by atomic force microscope and field emission scanning electron microscope. The sensitivity of zinc oxide NRs films to 100ppm vapor methanol, ethanol and NH3 gas as a function of working temperature. As evident, the sensitivity increases with the temperature and reaches a maximum value in correspondence of T = 200-300°C. If the temperature increases again, the sensitivity decreases. [ABSTRACT FROM AUTHOR]

Being able to identify problems and bring them to the attention of OR team colleagues is crucial for the safety of both patients and perioperative team members; however, being able to do this means being comfortable with speaking up under circumstances that may be difficult. Disruptive or intimidating coworker behavior also makes speaking up difficult, but it is important to address in the interest of providing safe, effective care to patients. To remedy this, health care workers should create awareness of the problem and motivate others to take action; establish a culture of respect; set expectations to help eliminate disrespectful behavior; and create a learning environment that eliminates hierarchical structures, fosters professionalism, demonstrates respect, and enforces a zero tolerance policy. [ABSTRACT FROM AUTHOR]

Highlights: [•] We model the social and structural bases of a strong component using ERGM. [•] While mutual reachability in strong components suggests parity, we find hierarchy. [•] Some nodes are densely interconnected; others are weakly attached to the component. [•] Strong components stem from triadic clustering and lack of preferential attachment. [•] These structural processes link to multiplicity of social connectivity in Florence. [Copyright &y& Elsevier]

Abstract: Government agencies and large corporations meet similar problems related to control of agents dealing with outsiders: citizens under audit of the agency or clients of the company. In such interaction there typically exists a possibility of collusion. In order to prevent it, agencies and corporations usually organize hierarchical controlling structures. The present paper considers game- theoretic models of such structures and studies a problem of their optimal organization. [Copyright &y& Elsevier]

A serious problem limiting the applicability of the fuzzy neural networks is the "curse of dimensionality", especially for general continuous functions. A way to deal with this problem is to construct a dynamic hierarchical fuzzy neural network. In this pa-per, we propose a two-stage genetic algorithm to intelligently construct the dynamic hierarchical fuzzy neural network (HFNN) based on the merged-FNN for general continuous functions. First, we use a genetic algorithm which is popular for flowshop scheduling problems (GA_FSP) to construct the HFNN. Then, a reduced-form genetic algorithm (RGA) optimizes the HFNN constructed by GA_FSP. For a real-world application, the presented method is used to approximate the Taiwanese stock market. [ABSTRACT FROM AUTHOR]

Stackelberg models for hierarchical oligopolistic markets with a homogenous product were studied by researchers extensively. The goal of this paper is to extend the classical solution in closed form of the Stackelberg model for a general hierarchical structures composed by firms arranged into groups of different hierarchical levels. [ABSTRACT FROM AUTHOR]

• We first develop a simple film with good wet strength, rapid water response and water-induced shape memory. • The mechanical robustness of MCP films is improved in low pH solutions, and the films show a rapid pH stimulus response. • MCP films exhibit excellent water-induced shape memory and a rapid pH stimulus response. • After rapid bend-release repetitions (0°–90°–0°) for 500 cycles, the resistive bending sensor deliver stable electrical signals. [Display omitted] Development of multi-functional water-sensitive shape memory material is crucial for applications in smart textiles, artificial intelligence, and biomedical areas. However, it remains a great challenge to achieve good biocompatibility, rapid water response, and robust mechanical strength in one single material. In this respect, we report a green approach to produce a series of multi-functional water-sensitive memory films (named MCP films) from sisal cellulose microcrystals (MSF-g-COOH), peach gum polysaccharide (PGP), citric acid (CA), and graphene nanosheets (GN). After crosslinking with CA, MCP films exhibit excellent water-induced shape memory and rapid pH stimulus response. More importantly, MCP films can effectively amplify different external motion stimuli by converting them into independent electrical signals to achieve accurate and continuous perception of bending. A high-performance resistive bending sensor was further fabricated from the MCP films to mimic natural human skin. The resistive bending sensor exhibited excellent water-responsive shape memory, self-adhesion, and bending sensitivity, which can be used in electronic skin, human-machine interactions, intelligent wearable devices, personalized health monitoring and other applications. Our work successfully demonstrates the application of the water-sensitive shape memory films in electronic skin and health-monitoring components, and fills the gap between material design and high-performance devices. [ABSTRACT FROM AUTHOR]

Various performance benefits such as low latency and high bandwidth have turned fog computing into a well-accepted extension of the cloud computing paradigm. Many fog computing systems have been proposed so far, consisting of distributed compute nodes which are often organized hierarchically in layers. To achieve low latency, these systems commonly rely on the assumption that the nodes of adjacent layers reside close to each other. However, this assumption may not hold in fog computing systems that span over large geographical areas, due to the wide distribution of the nodes. To avoid relying on this assumption, in this paper we design distributed algorithms whereby the compute nodes measure the network proximity to each other, and self-organize into a hierarchical or a flat structure accordingly. Moreover, we implement these algorithms on geographically distributed compute nodes, and we experiment with image processing and smart city use cases. Our results show that compared to alternative methods, the proposed algorithms decrease the communication latency of latency-sensitive processes by 27%–43%, and increase the available network bandwidth by 36%–86%. Furthermore, we analyze the scalability of our algorithms, and we show that a flat structure (i.e., without layers) scales better than the commonly used layered hierarchy due to generating less overhead when the size of the system grows. [ABSTRACT FROM AUTHOR]

Hierarchical interlocking leads to optimal mechanical properties for sutures in nature. Inspired by this, a design method for describing a hierarchal triangular suture joint based on Koch fractal interlocking is developed. The effect of geometrical interlocking was examined by the analysis of the load transmission between joined parts. Samples of hierarchal suture joints were fabricated by using a high-resolution 3D printer and tensile tests were conducted to examine the mechanical behavior of these joints. The surface displacement and strain fields were obtained using the Digital Image Correlation (DIC) technology where the images were taken by a high-resolution microscope camera. Finite element models of the hierarchal suture joints were generated to simulate the tensile responses and to predict the stress distributions and failure modes. The numerical results show good agreement with the experimental data. The results of this study show that the second order suture joint with a sinusoidal center line exhibits not only high strength but also high ductility. Moreover, by increasing the hierarchical order from two to three, the stiffness and strength do not improve while the fracture toughness actually decreases, suggesting that increasing the fractal complexity does not always lead to the improvement of the structure's load-carrying capacity, even with low iterations for the fractal complexity. The results obtained in this study can serve as a guideline to the engineering design of suture joints with fractal interlocks. [ABSTRACT FROM AUTHOR]