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Electromagnetic radiation pollution has become more serious in our daily life. The portable, flexible materials with an ultrahigh electromagnetic interference shielding effectiveness (EMI SE) are highly desirable to meet the needs of different applications. In this study, such a material was prepared by combining cellulose paper substrate with an effective electroless plating, which involved successive steps of 3-aminopropyltriethoxysilane (APTES) modification, PdCl2 activation and nickel coating deposition. The interaction mechanism among cellulose paper, APTES and PdCl2 was researched by FTIR and XPS measurements. According to SEM and XRD analyses, the nickel particles, with an average grain size of 14.742 nm, were densely deposited on the surface of cellulose paper, which formed excellent conductive paths. The electrical conductivity and EMI SE increased with an increase in plating time. When the plating time was 60 min, the sheet resistance was 97.1 mΩ/sq, and the EMI SE reached 44.1 dB in a frequency range of 8.2–12.4 GHz. The deposited Ni coating improved the self-cleaning and corrosion resistance properties of the cellulose paper. This work provides a sustainable, multifunctional, flexible cellulose paper-based shielding material that can achieve large-scale production.

Corrosion-resistant electromagnetic shielding materials with high conductivity and excellent magnetic properties are urgently needed to resolve the issue of electromagnetic radiation pollution. Her...

Sustainable low-cost cellulose-based electronics has exhibited brighter prospects. In this study, a laminated felt-like electromagnetic shielding material was prepared by using cellulose paper as the matrix through the self-foaming effect in electroless nickel plating process in which an efficient palladium-free activation was conducted that alkaline sodium borohydride (NaBH4) reduced nickel ions into nickel cluster to initiate the plating process. NaOH concentration in NaBH4 solution, pH of the plating bath and the plating time affected the thickness, metal deposition and surface resistance of the electromagnetic shielding material. By understanding the morphology, inner structure, chemical component and thermal stability, the pH in the plating solution is a key for the preparation. When the pH was 8.51, the electromagnetic shielding effective reached 65 dB in the frequency ranges of 9 kHz to 1.5 GHz, which could shield more than 99.99% electromagnetic radiation. This work offers a novel and feasible path to develop functional cellulose-based materials.

The functional design of paper-based material surfaces with renewable functions and environmentally friendly properties is prevalent nowadays. Herein, a superhydrophobic surface with a coral reef-like structure was prepared on filter paper by electroless copper plating, rapid silver nitrate etching, and facile 1-hexadecanethiol impregnation. After low-surface-energy thiol treatment, this unique coral reef-like structure surface showed excellent superhydrophobicity with a water contact angle of 163.8° and superoleophobicity with an oil contact angle of 0°, which could be used for oil-water separation and had a separation efficiency above 89.17% after 12 consecutive oil-water separations. Because the copper layer and silver nanostructure are both excellent conductive materials, the modified paper exhibited excellent electromagnetic shielding properties, and the electromagnetic interface shielding effectiveness exceeded 63 dB from 9 kHz to 1.5 GHz. The modified paper also had excellent self-cleaning properties and a better corrosion resistance. The unique three-dimensional interweaving structure between the cellulose fibers in the filter paper is fully utilized, and the substitution reaction between the silver ion and the copper coating produces a coral reef-like structure, which provides a new strategy for promoting the wide application of paper-based materials.

In order to prepare a film with good mechanical and barrier property for fruit preservation, the locust bean gum (LBG) coating was reinforced by carboxycellulose nanocrystal (C-CNC). The effect of C-CNC on the films was studied by analyzing the morphology, thermal stability, mechanical property, light transmittance and barrier property of the composite films. SEM indicated that LBG and C-CNC had good compatibility and C-CNC was dispersed in the LBG matrix well. The Fourier transform infrared spectroscopy analysis showed that there was no new chemical bond formed between LBG and C-CNC. The tensile strength (TS) and elongation at break (EB) of the LBG/C-CNC films increased by 43.69% and 49.13%, respectively. The light transmittance of LBG/C-CNC films at 500 nm increased from 48.84 to 56.49%. The water vapor transmission rate and oxygen transmission rate decreased from 7.05×10−11 and 2.75 to 4.71×10−11 g m − 1 s − 1 Pa−1 and 0.83 cm3 mm m − 2 day−1 atm−1, respectively. LBG/C-CNC coatings reduced the weight loss rate of strawberries by 19.42% and could be easily peeled off after soaked in water for 10 min and without affecting their taste. Therefore, the work provides a feasible and green method for extending the shelf life of strawberries and cherry tomatoes.

In order to reduce the loss of resources and improve the efficiency of the system, efficient methods are required to solve mobile robot maze. In this paper, the Q-learning method is applied to enable the constantly update of the Q table for robot under the feedback of the maze. Specifically, it is essentially an iterative process, which adjusts the path during moving and uses the optimal path to find the correct exit eventually. By comparing the way in different environment we draw a conclusion that through Q-learning the robot can find the shortest way to solve the maze.

Highly efficient shielding materials with an excellent electromagnetic wave absorption have gained increased attention. A new design was used to provide cellulose paper with a high electromagnetic shielding effectiveness (EMI SE) and improve the absorption performance by constructing an asymmetry sandwich structure that consisted of a dense nickel coating, Fe

This study aimed to delineate cortico-striato-thalamo-cerebellar network profiles based on static and dynamic connectivity analysis in genetic generalized and focal epilepsies with generalized tonic-clonic seizures, and to evaluate its potential for distinguishing these two epilepsy syndromes. A total of 342 individuals participated in the study (114 patients with genetic generalized epilepsy with generalized tonic-clonic seizures (GE-GTCS), and 114 age- and sex-matched patients with focal epilepsy with focal to bilateral tonic-clonic seizure (FE-FBTS), 114 healthy controls). Resting-state fMRI data were examined through static and dynamic functional connectivity (dFC) analyses, constructing cortico-striato-thalamo-cerebellar networks. Network patterns were compared between groups, and were correlated to epilepsy duration. A pattern-learning algorithm was applied to network features for classifying both epilepsy syndromes. FE-FBTS and GE-GTCS both presented with altered functional connectivity in subregions of the motor/premotor and somatosensory networks. Among these two groups, the connectivity within the cerebellum increased in the static, while the dFC variability decreased; conversely, the connectivity of the thalamus decreased in FE-FBTS and increased in GE-GTCS in the static state. Connectivity differences between patient groups were mainly located in the thalamus and cerebellum, and correlated with epilepsy duration. Support vector machine (SVM) classification had accuracies of 66.67%, 68.42%, and 77.19% when using static, dynamic, and combined approaches to categorize GE-GTCS and FE-GTCS. Network features with high discriminative ability predominated in the thalamic and cerebellar connectivities. The network embedding of the thalamus and cerebellum likely plays an important differential role in GE-GTCS and FE-FBTS, and could serve as an imaging biomarker for differential diagnosis.

Highly efficient shielding materials with an excellent electromagnetic wave absorption have gained increased attention. A new design was used to provide cellulose paper with a high electromagnetic shielding effectiveness (EMI SE) and improve the absorption performance by constructing an asymmetry sandwich structure that consisted of a dense nickel coating, Fe3O4 nanoparticles and a porous nickel layer. This unique structure caused a “multiple reflection-absorb-reflection” process when the electromagnetic waves penetrated the sample. The EMI absorption (SEA) and total SE (SET) increased with Fe3O4 absorption time increasing at 8.2–12.4 GHz, which was attributed to the synergistic effect between porous nickel layer and Fe3O4 nanoparticles. The SEA and SET of the sample with a thickness of 0.195 mm can achieved 18.57 and 41.88 dB, respectively. The design was conducive to improving the magnetic and corrosion resistance properties. This study provided a novel path to obtain a low cost and lightweight electromagnetic shielding material that can reduce secondary radiation.