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As with all stylish 2D functional materials, tellurene and tellurides possessing excellent physical and chemical properties such as high environmental stability, tunable narrow bandgap, and lower thermal conductivity, have aroused the great interest of the researchers. These properties of such materials also form the basis for relatively newfangled scholarly fields involving advanced topics, especially for broadband photodetectors. Integrating the excellent properties of many 2D materials, tellurene/telluride‐based photodetectors show great flexibility, higher frequency response or faster time response, high signal‐to‐noise ratio, and so on, which make them leading the frontier of photodetector research. To fully understand the excellent properties of tellurene/tellurides and their optoelectronic applications, the recent advances in tellurene/telluride‐based photodetectors are maximally summarized. Benefiting from the solid research in this field, the challenges and opportunities of tellurene/tellurides for future optoelectronic applications are also discussed in this review, which might provide possibilities for the realization of state‐of‐the‐art high‐performance tellurene/telluride‐based devices.

The high oxidation activity of coinage metals (Cu, Ag and Au) has been widely applied in various important reactions, such as oxidation of carbon monoxide, alkenes or alcohols. The catalytic behavior of those inert metals has mostly been attributable to their size effect, the physical effect. In the present study, the chemical effects on their high oxidation activity have been investigated. We mechanistically examine the direct and oxidative dehydrogenation (partial oxidation) reactions of ethanol to acetaldehyde on a series of transition metals (groups 9, 10 and 11) with identical physical characteristics and varied chemical origins using density functional theory (DFT) calculations and electronic structure analyses at the GGA-PW91 level. The energetic results show that coinage metals have much lower activation energies and higher exothermicities for the oxidative dehydrogenation steps although they have higher energy for the direct dehydrogenation reaction. In the electronic structure analyses, coinage metals with saturated d bands can efficiently donate electrons to O* and OH*, or other electronegative adspecies, and better promote their p bands to higher energy levels. The negatively charged O* and OH* with high-lying p bands are responsible for lowering the energies in oxidative steps. The mechanistic understanding well explains the better oxidation activity of coinage metals and provides valuable information on their utilization in other useful applications, for example, the dehydrogenation process.

A novel analytical modeling and dynamic manipulation control method of the multi-fingered hand robot has been proposed in the paper. Based on the contact constraints, the explicit dynamics modeling of the hand robot manipulating an object is hierarchically established by Udwadia-Kalaba equation with no auxiliary variable (e.g., Lagrange multipliers or quasi-generalized variables). Through the second order of the contact constraints, the grasping forces of the hand robot in the manipulation work space are derived explicitly and decoupled with the control torques of the finger joints. Consider the hand robot and the object as an entire system in the control design. Motivated by Udwadia's work, the manipulation task of the grasped object is novelly used to formulate a set of servo constraints. In virtue of following the servo constraints, the hand robot can manipulate the object to accomplish the desired task. With the formulated contact forces model, a model-based dynamic control method is proposed for the hand robot to handle the object, which does not depend on the force feedback from the fingertips sensors (force sensorless). The system performance under

The dynamic covalent properties of graphene oxide (GO) are of fundamental interest to a broad range of scientific areas and technological applications. It remains a challenge to access the feasible...

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Mo fiber-reinforced resin mineral composite (RMC) belongs to a multiphase material, whose mechanical strength depends on the property of components and microstructure characteristics of Mo fibers including surface state, fiber content, fiber shape, and so on. The reinforcing mechanism of Mo fiber is analyzed and the reinforcing effects of new and scrap fibers on RMC are studied, respectively, in the paper. Typical samples with different fiber parameters are prepared to validate the aforementioned assumptions. Experimental results and finite element simulation prove that scrap Mo fibers can improve the mechanical properties of RMC better than ordinary new Mo fibers because of the discharge pits randomly distributed on the surface of scrap fibers. The reinforcing effect is best while the fiber content is 1.2% of the total mass. If the length, diameter, and mass fraction of fibers are identical, special-shaped fibers such as U, V, N, W perform better obviously, and their maximum pulling load is much bigger than ordinary linear fibers.

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