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Aqueous zinc (Zn) chemistry features intrinsic safety, but suffers from severe irreversibility, as exemplified by low Coulombic efficiency, sustained water consumption and dendrite growth, which hampers practical applications of rechargeable Zn batteries. Herein, we report a highly reversible aqueous Zn battery in which the graphitic carbon nitride quantum dots additive serves as fast colloid ion carriers and assists the construction of a dynamic & self-repairing protective interphase. This real-time assembled interphase enables an ion-sieving effect and is found actively regenerate in each battery cycle, in effect endowing the system with single Zn2+ conduction and constant conformal integrality, executing timely adaption of Zn deposition, thus retaining sustainable long-term protective effect. In consequence, dendrite-free Zn plating/stripping at ~99.6% Coulombic efficiency for 200 cycles, steady charge-discharge for 1200 h, and impressive cyclability (61.2% retention for 500 cycles in a Zn | |MnO2 full battery, 73.2% retention for 500 cycles in a Zn | |V2O5 full battery and 93.5% retention for 3000 cycles in a Zn | |VOPO4 full battery) are achieved, which defines a general pathway to challenge Lithium in all low-cost, large-scale applications. Metallic zinc is an ideal anode material for aqueous rechargeable batteries but reversibility is a challenge. Here, the authors realise a dynamic real-time reconstructed interphase on zinc anode formed by graphitic carbon nitride quantum dot as an electrolyte additive to improve the performance of Zn metal anodes. [ABSTRACT FROM AUTHOR]

Lignin is the second most abundant and the only nature polymer rich in aromatic units. Although aromatic-unit-rich precursors often yield soft carbon after carbonization, the side chains in lignin crosslink with the aromatic units and form a rigid three-dimensional (3D) structure which eventually leads to hard carbons. Through a graphene oxide-catalyzed decomposition and repolymerization process, we successfully reconstructed lignin by partially tailoring the side chains. Compared to directly carbonized lignin, the carbonized reconstructed lignin possesses significantly fewer defects, 86% fewer oxygen-functionalities, 82% fewer micropores, and narrower interlayer space. These parameters can be tuned by the amount of catalysts (graphene oxide). When tested as anode for K-ion and Na-ion batteries, the carbonized reconstructed lignin delivers notably higher capacity at low-potential range (especially for Na-storage), shows much-improved performance at high current density, and most importantly, reduces voltage hysteresis between discharge and charge process by more than 50%, which is critical to the energy efficiency of the energy storage system. Our study reveals that the voltage hysteresis in K-storage is much severer than that in Na-storage for all samples. For practical K-ion battery applications, the voltage hysteresis deserves more attention in future electrode materials design and the reconstruct ion strategy introduced in this work provides potential low-cost solution. [ABSTRACT FROM AUTHOR]

Haptic feedback plays a large role in enhancing immersion and presence in VR. However, previous research and commercial products have limitations in terms of variety and locations of delivered feedbacks. To address these challenges, we present HapticSnakes, which are snake-like waist-worn robots that can deliver multiple types of feedback in various body locations, including taps-, gestures-, airflow-, brushing- and gripper-based feedbacks. We developed two robots, one is lightweight and suitable for taps and gestures, while the other is capable of multiple types of feedback. We presented a design space based on our implementations and conducted two evaluations. Since taps are versatile, easy to deliver and largely unexplored, our first evaluation focused on distinguishability of tap strengths and locations on the front and back torso. Participants had highest accuracy in distinguishing feedback on the uppermost regions and had superior overall accuracy in distinguishing feedback strengths over locations. Our second user study investigated HapticSnakes' ability to deliver multiple feedback types within VR experiences, as well as users' impressions of wearing our robots and receiving novel feedback in VR. The results indicate that participants had distinct preferences for feedbacks and were in favor of using our robots throughout. Based on the results of our evaluations, we extract design considerations and discuss research challenges and opportunities for developing multi-haptic feedback robots. [ABSTRACT FROM AUTHOR]

Nanocellulose is a sustainable and eco-friendly nanomaterial derived from renewable biomass. In this study, we utilized the structural advantages of two types of nanocellulose and fabricated freestanding carbonized hybrid nanocellulose films as electrode materials for supercapacitors. The long cellulose nanofibrils (CNFs) formed a macroporous framework, and the short cellulose nanocrystals were assembled around the CNF framework and generated micro/mesopores. This two-level hierarchical porous structure was successfully preserved during carbonization because of a thin atomic layer deposited (ALD) AlO conformal coating, which effectively prevented the aggregation of nanocellulose. These carbonized, partially graphitized nanocellulose fibers were interconnected, forming an integrated and highly conductive network with a large specific surface area of 1,244 m·g. The two-level hierarchical porous structure facilitated fast ion transport in the film. When tested as an electrode material with a high mass loading of 4 mg·cm for supercapacitors, the hierarchical porous carbon film derived from hybrid nanocellulose exhibited a specific capacitance of 170 F·g and extraordinary performance at high current densities. Even at a very high current of 50 A·g, it retained 65% of its original specific capacitance, which makes it a promising electrode material for high-power applications. [ABSTRACT FROM AUTHOR]

Ligand-directed targeting and capturing of cancer cells is a new approach for detecting circulating tumor cells (CTCs). Ligands such as antibodies have been successfully used for capturing cancer cells and an antibody based system (CellSearch®) is currently used clinically to enumerate CTCs. Here we report the use of a peptide moiety in conjunction with a microcantilever array system to selectively detect CTCs resulting from cancer, specifically breast cancer. A sensing microcantilever, functionalized with a breast cancer specific peptide 18-4 (WxEAAYQrFL), showed significant deflection on cancer cell (MCF7 and MDA-MB-231) binding compared to when exposed to noncancerous (MCF10A and HUVEC) cells. The peptide-functionalized microcantilever allowed efficient capture and detection of cancer cells in MCF7 spiked human blood samples emulating CTCs in human blood. A detection limit of 50-100 cancer cells mL-1 from blood samples was achieved with a capture yield of 80% from spiked whole blood samples. The results emphasize the potential of peptide 18-4 as a novel peptide for capturing and detecting cancer cells in conjunction with nanomechanical cantilever platform. The reported peptide-based cantilever platform represents a new analytical approach that can lead to an alternative to the various detection platforms and can be leveraged to further study CTCs. [ABSTRACT FROM AUTHOR]

The cutting forces are studied for the reaming of casting aluminium alloy ZL102 (ZAlSi12) using a four-flute PCD reamer on DMG DMU 50 linear five-axis CNC machine. Kistler Dynamometer is used to measure the cutting force ( X-, Y- and Z-axes) and torque. Three-coordinate measuring machine is used for measuring cylindricity of machined hole. The cutting force signatures are diagnosed by using Fast Fourier Transform (FFT) algorithm. FFT analysis suggests that fundamental frequency is only determined by cutting speed. The frequency for the thrust signal of cutting force is zero which illustrates that the thrust is constant when cutting speed and cutting feed are fixed. The relationship between the cutting force and cutting parameter are investigated by using FFT filtering. High value of cutting feed and the low cutting speed provide the higher thrust. The optimized machining parameters are provided relative to cutting force ( Fx and Fy) and the cylindricity of reamed holes. [ABSTRACT FROM AUTHOR]

Mechanical signaling involved in molecular interactions lies at the heart of materials science and biological systems, but the mechanisms involved are poorly understood. Here we use nanomechanical sensors and intact human cells to provide unique insights into the signaling pathways of connectivity networks, which deliver the ability to probe cells to produce biologically relevant, quantifiable and reproducible signals. We quantify the mechanical signals from malignant cancer cells, with 10 cells per ml in 1000-fold excess of non-neoplastic human epithelial cells. Moreover, we demonstrate that a direct link between cells and molecules creates a continuous connectivity which acts like a percolating network to propagate mechanical forces over both short and long length-scales. The findings provide mechanistic insights into how cancer cells interact with one another and with their microenvironments, enabling them to invade the surrounding tissues. Further, with this system it is possible to understand how cancer clusters are able to co-ordinate their migration through narrow blood capillaries. Samadhan Patil et al. report a new method for improving the sensitivity and reproducibility of mechanobiological measurements in malignant cancer cells. Their findings provide insight into the interaction of cells with each other and the microenvironment and may impact our understanding of metastasis. [ABSTRACT FROM AUTHOR]