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Summary: Computer vision-based wood identification has been successfully applied to recognize tree species using digital images of wood sections or surfaces. However, this image-to-species approach can only recognize a limited number of species due to two main reasons: 1) the lack of a good reference database requiring high-quality standardized images from multiple individuals of hundreds or even thousands of traded timber species, and 2) species not included in the reference database cannot be identified without expert knowledge. Another bottleneck is that the feature extraction process used by these species recognition approaches is a black box, thereby creating a discrepancy between machine learning features and wood anatomical features. This discrepancy prevents wood anatomists from understanding how these machine-learning algorithms work. Here, we survey currently existing methods used in feature extraction, classification, and deep learning methods applied in wood identification along with their pitfalls and opportunities. As an example of how the field could move forward, we launch the idea of building an image-to-features-to-species identification approach based on microscopic wood images as well as text files comprising wood anatomical descriptions. If we can manage machine learning-based algorithms to recognize the main wood anatomical traits that experts use to identify species in a (semi-)automated way, this would boost wood identification in two ways: (1) extensive reference databases for each species would become less crucial as the databases are ordered at the trait level, (2) timber identification would become more feasible for species that have not yet been included in the reference database as long as wood anatomical descriptions are available. [ABSTRACT FROM AUTHOR]

Detailed anatomical features of bark are used and interpreted in plant taxonomy, phylogenetics, and other areas of plant science. However, the delicate nature of bark cells, combined with the difficulty of obtaining high-quality sections and reliable data, limits the potential for utilizing and processing bark. In this study, the anatomical structure of the bark of 10 Quercus species growing in Yunnan Province, China, was characterized in detail. The results indicate that the anatomical features of the barks of 10 Quercus spp. show a certain degree of consistency. Specifically, sieve tubes are distributed in solitary elements or in small groups, mostly as compound sieve plates containing 2–8 sieve areas, suggesting that Quercus spp. may occupy a conservative evolutionary position. Additionally, for the first time, this study reports the presence of simple sieve plates in the sieve tube elements of Quercus phloem. Each sieve tube element has a companion cell on one side. The companion cell strands contain 2–7 cells. Axial parenchyma is diffuse, with parenchyma strands typically consisting of 4–7 cells; druses are present within chambered crystalliferous cells. Phloem rays are of two distinct sizes and often exhibit dilatation and sclerification, and the ray composition consists of procumbent cells. Sclerenchyma is composed of fibers and sclereids, both of which contain prismatic crystals. Most of the fibers are gelatinous fibers, which are distributed in discontinuous tangential bands of about five cells in width. Sclereids appear in clusters. The presence of sclerenchyma provides mechanical support to the bark, reducing the collapse of the phloem. Periderm usually consists of around 10–30 layers of phellem, and Quercus acutissima and Q. variabilis can reach dozens or hundreds layers. The phelloderm typically consists of from two to five layers, with Q. variabilis having up to ten or more layers. The filling tissue of lenticels in all Quercus species is nonstratified (homogeneous) and largely nonsuberized. Overall, this study enriches our comprehension of Quercus bark anatomy, elucidating evolutionary patterns, functional adaptations, and ecological ramifications within this significant botanical genus. [ABSTRACT FROM AUTHOR]

A novel binder-free electrode material, Co3S4@rGO/Ni foam, was synthesized with a facile one-step method under mild experimental conditions. 1-Thioglycerol was utilized as the catalyst for the low-temperature hydrolysis of sodium thiosulfate. S2−, the hydrolysis product, reacted with cobalt cation to produce Co3S4, which was coated on rGO nanosheets. Co3S4-encapsulated rGO spontaneously assembled on Ni foam exhibiting a highly porous flower-like morphology. Co3S4@rGO/Ni foam was characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS) were used to investigate the energy storage performance of Co3S4@rGO/Ni foam, which demonstrated high areal capacitance (12.17 F cm−2 at 10 mA cm−2) and ultra-long cycling life (98.9% capacitance retention after 5000 GCD cycles). The asymmetric supercapacitor device assembled with Co3S4@rGO/Ni foam and activated carbon (AC) as positive and negative electrodes may provide a high energy density of 6.18 W h m−2 at power density of 37.3 W m−2. [ABSTRACT FROM AUTHOR]

A facile method was proposed to synthesize a Co3S4-based binder-free electrode (Co3S4/Ni foam) in an aqueous solution containing 1-thioglycerol, cobalt nitrate, and sodium thiosulfate at 60 ℃, followed by calcination at 400 ℃. The Co3S4 membrane on Ni foam consists of spherical and elliptical nanoparticles, which were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The electrochemical investigation of the Co3S4/Ni foam electrode with cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) exhibits high areal capacitance (7.32 F cm−2 at 10 mA cm−2) and ultra-long cycling life (capacitance retention of 75% after 5000 charge/discharge cycles). The asymmetric supercapacitor device (ASC) assembled with Co3S4/Ni foam and activated carbon (AC) as positive and negative electrodes presents excellent electrochemical performances, suggesting the great application prospect of Co3S4/Ni foam. [ABSTRACT FROM AUTHOR]

The rGO/hemoglobin/CdS biocomposite (rGO/Hb/CdS) were prepared via a simple route. The water-soluble rGO/CdS composite was synthesized in aqueous solution with a facile hydrothermal route. CdS nanoparticles (NPs) were anchored uniformly on the graphene nanosheets. With L-cysteine (Cys) as the molecular linker, the Hb molecules were then adsorbed onto the CdS NPs to produce the rGO/Hb/CdS biocomposite NPs. The rGO/Hb/CdS was characterized employing UV-vis spectroscopy, powder X-ray diffraction (XRD), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM). The electrochemical behaviors of rGO/Hb/CdS were characterized with cyclic voltammetric technique (CV). A pair of well-defined and quasi-reversible cyclic voltammetric peaks was observed. The cyclic voltammogram demonstrated the direct electron transfer of the Fe(III)/Fe(II) couple of Hb. The glassy carbon electrode (GCE) modified with rGO/Hb/CdS displays an excellent electrocatalytic response to the reduction of H2O2 with a detection limit of 6 × 10−7 M (S/N = 3). A linear calibration curve can be observed in the range of 1.9 × 10−6 ∼ 1.5 × 10−4 M. [ABSTRACT FROM AUTHOR]