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In order to solve the problems of complex operation and low degree of automation existing in the feeding of dairy cows, an automatic intelligent feeding car was developed, which can automatically realize weighing and batching, crushing and mixing. Feeding at fixed points and returning by tracking. The design is based on STM32F103RBT6 micro-controller as the core, with electromagnetic tracking module, weighing module, dual drive DC motor module and other modules. The least square method is used to fit the accuracy of the pressure sensor through experiments, and the accuracy of the feeding rate in the electromagnetic tracking process is optimized by calibrate the pressure sensor, returning to the parameters to adjust the speed before feeding. After calibration and debugging, the intelligent feeding car runs stably according to the given parameters, and the feeding amount is more accurate. Ultimately, the feed quantity is more accurate, the labor cost is effectively reduced, the feeding efficiency is improved in this design, and a new idea is provided for feeding automation.

The fabrication of flexible freestanding electrodes with superior electrochemical performance is challenging now in consumer electronics miniaturization. Herein, we demonstrate a simple and scalable synthesis of hollow silicon nanosheets, which then hybridizes with rGO into flexible films by layer-by-layer assembly process. The resulting Si/rGO films, when applied as a free-standing LIBs anode, exhibit a high reversible specific capacity of 904 mAh g−1 at 200 mA g−1 (about 2 times higher than theoretical value of graphite anode), and meanwhile maintain a long cycle life (650 mAh g−1 after 150 cycles). In addition, a flexible full battery has also been assembled based on the flexible film as an anode and the commercial LiCoO2 as a cathode, which impressively delivers a high specific capacity of 700 and 613 mAh g−1 at 50 mA g−1 after 15 cycles in flat and bent state, respectively. Such intriguing electrochemical performances can be mainly attributed to the two-dimensional hollow nanostructure of silicon and their strong synergistic effect with rGO. It is reckoned that our Si/rGO films are a promising anode for advanced flexible LIBs.

Here, a novel and facile method is reported for manufacturing a new stretchable conductive material that integrates a hybrid three dimensional (3D) carbon nanotube (CNT)/reduced graphene oxide (rGO) network with a porous poly(dimethylsiloxane) (p-PDMS) elastomer (pPCG). This reciprocal architecture not only alleviates the aggregation of carbon nanofillers but also significantly improves the conductivity of pPCG under large strains. Consequently, the pPCG exhibits high electrical conductivity with a low nanofiller loading (27 S m−1 with 2 wt% CNTs/graphene) and a notable retention capability after bending and stretching. The simulation of the mechanical properties of the p-PDMS model demonstrates that an extremely large applied strain (eappl) can be accommodated through local rotations and bending of cell walls. Thus, after a slight decrease, the conductivity of pPCG can continue to remain constant even as the strain increases to 50%. In general, this architecture of pPCG with a combination of a porous polymer substrate and 3D carbon nanofiller network possesses considerable potential for numerous applications in next-generation stretchable electronics.

We demonstrate a new nanohybrid anode made up of graphene supported mesoporous single crystal Si (MSC-Si/G) on Cu foam by a facile method. Such intriguing nanohybrids are not only highly stable anode materials for LIBs with a high reversible capacity of 1703 mA h g−1 at 200 mA g−1 as well as rapid charge and discharge capability (390 mA h g−1 at 5000 mA g−1), but also show no obvious capacity fade after 160 cycles at 200 mA g−1 or over 130 cycles at 5000 mA g−1.

We have developed hierarchical double-shelled SnO2 hollow spheres by a sequential template-engaged method, in which the loosened SnO2 floccules are well-grown on the inside wall of the hollow spheres. The unique hierarchical structure could provide more active sites for Li–Sn alloying–dealloying reaction and fast insertion/extraction of Li+ ion with superb conductivity, helping to store more lithium (2578 mA h g−1) with great cycling stability.

In order to mitigate the drastic volumetric expansion (300%) of silicon (Si) during the lithiation process, we demonstrate the synthesis of novel Si nanowire arrays (n-SNWAs) with a coral-like surface on Cu foam via a one-step CVD method, in which the Cu foam can simultaneously act as a catalyst and current collector. The unique coral-like surface endows n-SNWAs with a high structural integrity, which is beneficial for enhancing their electrochemical performance. In addition, the as-prepared n-SNWAs on Cu foam can be directly applied as the anode for lithium-ion batteries (LIBs), exhibiting a very high reversible discharge capacity (2745 mA h g(-1) at 200 mA g(-1)) and a fast charge and discharge capability (884 mA h g(-1) at 3200 mA g(-1)), which is much higher than the conventional SNWAs (c-SNWAs, only 127 mA h g(-1) at 3200 mA g(-1)). Meanwhile, they deliver an improved cycling stability (2178 mA h g(-1) at 400 mA g(-1) after 50 cycles). More significantly, the as-synthesized n-SNWAs on Cu foam also possess a superior specific areal capacity of 4.1 mA h cm(-2) at 0.6 mA cm(-2). Such excellent electrochemical performance is superior, or at least comparable, to the best report for Si anode materials. Combining the cost-effective and facile preparation method, the present n-SNWAs on Cu foam can serve as a promising anode for LIBs.

New flexible and conductive materials (FCMs) comprising a quartz fiber cloth (QFC) reinforced multi-walled carbon nanotubes (MWCNTs)-carbon aerogel (QMCA) and poly(dimethylsiloxane) (PDMS) have been successfully prepared. The QMCA-PDMS composite with a very low loading of MWCNTs (∼1.6 wt%) demonstrates enhanced performance in tensile strength (129.6 MPa), modulus (3.41 GPa) and electromagnetic interference (EMI) shielding efficiency (SE) (∼16 dB in X-band (8.2-12.4 GHz) region). Compared to the QC (where MWCNTs were simply deposited on the QFCs without forming aerogel networks) based PDMS composite, a ∼120%, 330% and 178% increase of tensile strength, modulus, and EMI SE was obtained, respectively. Moreover, the EMI SE of the QMCA-PDMS composite can further reach 20 dB (a SE level needed for commercial applications) with only 2 wt% MWCNTs. Furthermore, the conductivity of the QMCA-PDMS laminate can reach 1.67 S cm(-1) even with very low MWCNTs (1.6 wt%), which still remains constant even after 5000 times bending and exhibits an increase of ∼170% than that of MWCNT-carbon aerogel (MCA)-PDMS at 20% strain. Such intriguing performances are mainly attributed to their unique networks in QMCA-PDMS composites. In addition, these features can also protect electronics against harm from external forces and EMI, giving the brand-new FCMs huge potential in next-generation devices, like E-skin, robot joints and so on.