contaminants owing to their chemical affi nity with these contaminants, large surface area, porous structure, and other remarkable physical properties. [ 1 ] Due to their superior hydrophobic and oleophilic characteristics, carbon aerogels can effectively absorb a variety of oils and organic solvents without water penetration. However, most of these carbon aerogels are synthesized from carbonaceous precursors, such as carbon-containing polymers, [ 2 ] carbon-containing fi bers, [ 3 ] carbon nanofi bers, [ 4 ] carbon nanotubes, [ 5 ] and graphene. [ 6 ] Problems of these expensive precursors and complex and energyconsuming process in the production of carbon aerogels restrict the practical use of carbon aerogels on a large-scale. In this regard, the utilization of renewable biomass as precursors, together with simple and low-energy treatment to fabricate sustainable carbon aerogels is strongly desired. [ 7 ] In this study, we employ nanofi brillated cellulose (NFC) as a sustainable and scalable precursor for producing carbon aerogels. The reason to choose NFC as the precursor is based on its unique structures and properties. First, cellulose is a good carbon source. Cellulose-containing woods have been used as the precursor of activated coals for many years. Second, comparing with traditional cellulosic pulps in the micrometer-scale, NFC produced by disintegration of pulps has much smaller diameters in nanometer-scale (typically <10 nm) as well as advantageous mechanical strength due to the extended chain crystals of cellulose and large specifi c surface areas. [ 8 ] Further, NFC is able to form porous aerogels with a microscopic network and a large specifi c surface area. Although the NFC aerogels are expected to use for absorbing or separating of oils and organic solvents from water, the separation effi ciency is low because of the strong hydrophilicity of cellulose. [ 9 ] To improve the absorbent performance, the surface of NFC aerogels was chemically modifi ed to be hydrophobic and oleophilic with TiO 2 coating [ 10 ] or vapor phase silanization. [ 11 ] However, these modifi ed NFC aerogels still showed a weak absorbent performance (<45 times of their own weight). Jiang and Hsieh synthesized a functionalized NFC aerogel by chemical vapor deposition of (triethoxyl(octyl) silane) which was able to absorb 139-356 times organic solvents or oils by weight. [ 12 ] Unfortunately, their NFC aerogel also absorbed water when it was immersed into water, Sustainable carbon aerogels with low density (≈7.8 mg cm −3 ), high porosity, high resiliency, excellent hydrophobicity, and oleophilic characteristics are synthesized by employing nanofi brillated cellulose as the precursor. The as-prepared carbon aerogels show a remarkable capacity for the absorption of a variety of oils and organic solvents with weight gains ranging from 7422 to 22356. Under extreme conditions (e.g., at severe temperatures and in corrosive liquids), these carbon aerogels still demonstrate a superior absorption performance. Furthermore, a device ...

Sentiment analysis is widely studied to extract opinions from user generated content (UGC), and various methods have been proposed in recent literature. However, these methods are likely to introduce sentiment bias, and the classification results tend to be positive or negative, especially for the lexicon-based sentiment classification methods. The existence of sentiment bias leads to poor performance of sentiment analysis. To deal with this problem, we propose a novel sentiment bias processing strategy which can be applied to the lexicon-based sentiment analysis method. Weight and threshold parameters learned from a small training set are introduced into the lexicon-based sentiment scoring formula, and then the formula is used to classify the reviews. In this paper, a completed sentiment classification framework is proposed. SentiWordNet (SWN) is used as the experimental sentiment lexicon, and review data of four products collected from Amazon are used as the experimental datasets. Experimental results show that the bias processing strategy reduces polarity bias rate (PBR) and improves performance of the lexicon-based sentiment analysis method.

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In article number 1600004, W. Chen and co‐workers describe the preparation of sustainable carbon aerogels from wood nanofibrillated cellulose. The carbon aerogels demonstrate high capacities for the absorption of different oils and organic solvents. Under extreme conditions, these carbon aerogels still demonstrate a superior absorption performance. Further, a device based on a composite sponge with carbon sheets (generated via the disintegration of carbon aerogels) on the surface is successfully fabricated to materialize the large‐scale and continuous separation of containments from water.

This paper aims to obtain a fine wear-resistance cladding that can be applied in guide shoe of shearer. The performance of two cladding claddings fabricated by additive manufacturing technology, no chromium-high carbon (NCrHiC) claddings and high chrome-high carbon (HiCrHiC) claddings, was analyzed through a series of characterization experiments (optical microscope, hardness, coefficient of friction, wear rate, and surface morphology). The experimental results show that the NCrHiC cladding has obvious cracks and cracks are not observed on the surface of HiCrHiC cladding. However, the hardness and wear resistance of NCrHiC cladding is better than that of HiCrHiC cladding. The microstructure of NCrHiC cladding is composed of carbides, pearlite and ledeburite, and the one of HiCrHiC cladding is M(Fe, Cr)7C3 carbides and martensite. The worn width of HiCrHiC cladding is higher than that of NCrHiC cladding. Wear mechanism of NCrHiC cladding is abrasive wear while the one of HiCrHiC cladding is adhere wear.