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Operando XAS reveals that the copper catalysts undergo a remarkable reduction to the metallic state during CO2RR.

As a result of the trend toward economic globalization, the vigorous development of cross-border e-commerce has attracted many scholars to study this field, involving many related fields, such as consumer behavior, advertising, information systems, and supply chain management. Throughout the existing literature, it can be found that most of the research focuses on certain influencing factors of the development of cross-border e-commerce, and there is no systematic and macro- overview of the development trend of research in this field in recent years, nor the integration and analysis of keywords. Given that the research in the field of cross-border e-commerce is fragmented to a large extent, to effectively explore the research trend in this field, we must understand the current situation of cross-border e-commerce. Systematic bibliometric analysis can solve this problem by providing publishing trends and information on various topics. Therefore, based on the scientific database web, this study collected 198 references related to cross-border e-commerce from 2016 to 2021, briefly introduced the current situation and development trend of cross-border e-commerce, visually analyzed and refined the journals, authors, research institutions, countries, publication years, keywords, citations of academic publications in this field, and other key information, and summarized the development trend and path of CEBC in the existing research. It is helpful for researchers to solve the current research gap, understand the future research direction in this field, and help academia establish a strict knowledge system.

InP-based quantum dot (QD) light-emitting diodes (QLEDs) provide a heavy-metal-free route to size-tuned LEDs having high efficiency. The stability of QLEDs may be enhanced by replacing organic hole-injection layers (HILs) with inorganic layers. However, inorganic HILs reported to date suffer from inefficient hole injection, the result of their shallow work functions. Here, we investigate the tuning of the work function of nickel oxide (NiO

One of the major challenges in applying tomography methods for detecting defects in composite materials is the large image datasets generated during imaging, which require significant effort for the detection of damage. Machine-learning (ML) methods require a large training dataset and can be efficient in processing tomography datasets for defect detection. Methods need to be developed for processing images to train the ML algorithms, which is the focus of the present work. An additive manufactured fiber reinforced composite material is imaged using a micro-CT scan to generate an image set for defect detection. The microstructures are processed using the binarized statistical image features (BSIF) method for compression without compromising the desired information about defects. The result shows that the convolutional neural network model has a mean square error of 0.001 in fiber orientation prediction, and a scheme has been developed for defect detection based on the predictions obtained from the ML models.

Over the past decade, neuroscience has been integrated into information systems as a new methodology and perspective to study and solve related problems. Therefore, NeuroIS has emerged as a new cutting-edge research field. This review aimed to identify, summarize, and classify existing NeuroIS publications through knowledge mapping and bibliometric analysis. To effectively understand the development trend of NeuroIS, this study referred to the journal selection index of the Association of Business Schools in 2021 and journals above three stars in the field of information management as the main selection basis. A total of 99 neuroscience papers and their citation data were included from 19 major information systems journals of SCI/SSCI. This study analyzed bibliometric data from 2010 to 2021 to identify the most productive countries, universities, authors, journals, and prolific publications in NeuroIS. To this end, VOSviewer was used to visualize mapping based on co-citation, bibliographic coupling, and co-occurrence. Keywords with strong citation bursts were also identified in this study. This signifies the evolution of this research field and may reveal potential research directions in the near future. In selecting research methods and analysis tools for NeuroIS, content analysis was used to further conclude and summarize the relevant trends. Moreover, a co-citation network analysis was conducted to help understand how the papers, journals, and authors in the field were connected and related, and to identify the seminal or pioneering major literature. For researchers, network maps visualized mainstream research and provided a structural understanding of NeuroIS. The review concludes by discussing potential research topics in this field.

Our previous study explored the dual effect of lipoic acid on the regulation of IL-6 expression in C2C12 myotubes. However, the specific mechanism remains unclear. To evaluate IL-6 signaling in skeletal muscle, pCMV6-IL-6 was overexpressed in C2C12 myotubes. The real-time quantitative polymerase chain reaction was used to detect mRNA expression. Immunohistochemistry and a DeadEnd colorimetric TUNEL system were used to detect IL-6 localization and analyze the apoptosis in IL-6-overexpressing cells, respectively. A caspase-3/CPP32 colorimetric assay and Western blotting were used to analyze caspase-3 activity and protein expression, respectively. Our results showed the overexpressed IL-6 was not only located in the cytosol but also on the intracellular side of the cell membrane. Moreover, the nucleus did not demonstrate IL-6 overexpression. The DeadEnd colorimetric apoptosis detection assay results demonstrated that apoptotic nuclei were present in IL-6-overexpressing cells. However, the overexpressed IL-6 failed to promote caspase-3 activity. Notably, the exogenous pyrogen lipopolysaccharide (LPS) significantly promoted IL-6 mRNA expression and caspase-3 activity but did not induce apoptotic cell formation. Moreover, lipoic acid significantly upregulated IL-6, IL-6Ra, and gp130 mRNA expression and significantly increased caspase-3 activity but did not induce apoptotic cell formation. Lipoic acid significantly increased the p-Akt level in untreated cells but not in LY294002-treated cells. Taken together, our results suggesting that the overexpressed IL-6-induced apoptosis may not be mediated by caspase-3. LPS-induced IL-6 mRNA expression may not be involved in IL-6 classical signaling or trans-signaling in C2C12 myotubes. Lipoic acid-induced IL-6 mRNA expression may be mediated by IL-6 classical signaling in C2C12 myotubes. [Figure: see text].

Calycosin, a bioactive isoflavonoid isolated from root extracts of Astragalus membranaceus, has been reported to inhibit melanogenesis, the mechanism of which remains undefined. In this study, we interrogated the mechanistic basis by which calycosin inhibits melanin production in two model systems, i.e., B16F10 melanoma cells and zebrafish embryos. Calycosin was effective in protecting B16F10 cells from α-melanocyte-stimulating hormone (α-MSH)-induced melanogenesis and tyrosinase activity. This anti-melanogenic effect was accompanied by decreased expression levels of microphthalmia-associated transcription factor (MITF), a key protein controlling melanin synthesis, and its target genes tyrosinase and tyrosinase-related protein-2 (TRP-2) in calycosin-treated cells. Mechanistically, we obtained the first evidence that calycosin-mediated MITF downregulation was attributable to its ability to block signaling pathways mediated by cAMP response element-binding protein (CREB) and p38 MAP kinase. The protein kinase A (PKA) inhibitor H-89 and p38 inhibitor SB203580 validated the premise that calycosin inhibits melanin synthesis and tyrosinase activity by regulating the PKA/CREB and p38 MAPK signaling pathways. Moreover, the in vivo anti-melanogenic efficacy of calycosin was manifested by its ability to suppress body pigmentation and tyrosinase activity in zebrafish embryos. Together, these data suggested the translational potential of calycosin to be developed as skin-lightening cosmeceuticals.

Purpose This study used the colours of plates as atmospheric stimulus factors in the Mehrabian–Russell model of environmental influence, which served as the study’s basic background theory, to explore how plate colour affects consumer appetite preference and dining emotions in Chinese fine dining restaurants. The paper aims to discuss this issue. Design/methodology/approach The study used quantitative surveys and employed purposeful sampling and rolling snowball surveys of consumers in Chinese fine dining restaurants in Taipei; 581 effective surveys were collected from the test subjects. The research tools included a plate colour appetite preference scale and a dining emotion scale. Findings There were significant differences in age and gender in terms of appetite preference and plate colour. The plate colours with the highest appetite preference were gold, white and black. There were significant differences in plate colour appetite preference in terms of dining mood, with white and gold plates eliciting positive dining moods. Originality/value Most academic papers have focused on studying plates in Western dining, while very few studies have focused on the colour of Chinese dining plates. The greatest contribution and value of this study is its discovery of the colour combination of dining plates that can elicit appetite preferences and positive dining emotions among diners in Chinese fine dining restaurants. This information can be used to stimulate positive dining emotions among consumers and help restaurateurs improve the level of dining aesthetics.

Ball-bearing-like specimens are prepared with three groove factors (GF ≡ r/D; r: radius of groove; D: diameter of ball). Analyses of operating conditions are conducted for the thrust loads applied to the dry-contact specimens running with the maximum contact stress close to 2.0 GPa. The combined effect of surface roughness ((Ra)inner) of the inner raceway and groove factor becomes the controlling factor for the slip ratio (SR) arising at the tribocontact of ball and inner raceway, and the average friction coefficient ( μ ¯ ) of specimen. Both the inception time (TBR) of the instability in the running-in process and the inception time (TBS) of the instability arising in specimen's base material are governed by the average value ( S R ¯ ) of SR. The wavinesses of raceway are the controlling factor for the significant rise of frictional torque in the running-in regime and the TBR value. The fluctuations of frictional torque arising at the time behind TBR are confirmed to be the instability arising in the base material. The theoretical prediction for TBS is determined when μ ¯ reaches the threshold value, ( μ ¯ )threshold. For the specimens with the same GF, increasing (Ra)inner can elevate S R ¯ and μ ¯ . In the specimens with a relatively smaller (Ra)inner, GF is the dominant factor for S R ¯ ; however, (Ra)inner becomes the dominant factor for S R ¯ if the inner raceway is prepared with a relatively larger (Ra)inner. Increasing GF can result in a μ ¯ reduction, irrespective of the (Ra)inner value. Both TBS and TBR are reduced by the increasing S R ¯ . The wear losses of ball and the two raceways, however, increase as increasing S R ¯ .

Cs0.33WO3 nanomaterial absorbs a range of near-infrared (NIR) wavelength spanning 900–2400 nm, of which the main contributor of heat energy may be utilized for electrical generation. In this research, the capability of Cs0.33WO3 nanomaterial in enhancing the output of a thermoelectric (TE) device by trapping the absorbed heat at the hot-side surface of the device is investigated. The material is synthesized through a combination of the processes of co-precipitation and wet nano-grinding, and the characterization of its structural and optical properties was carried out using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and visible-near-infrared absorption spectroscopy. Likewise, the photothermal property of Cs0.33WO3 nanomaterial, in the form of solution or solid film, is assessed to gain better insight into its effects on the electrical output of the TE device, utilizing a laser with wavelength of 808 nm, a solar simulator, and sunlight in ambient environment. Moreover, the photoelectric property of the Cs0.33WO3 nanomaterial-incorporated TE device was evaluated in four different types of weather condition, sunny, sunny with partly cloudy, cloudy, and rainy; and our results indicate that Cs0.33WO3 nanomaterial is capable of enhancing the output of thermoelectric conversion in an ambient environment. In a complete sunny day, when compared with a bare thermoelectric device, the coating of Cs0.33WO3 nanomaterial with concentration of 0.66 wt% demonstrated a rise of 13.1% in the maximal attainable temperature and a corresponding increase of 291% in maximal output voltage.

Heteroatom-doped carbons have been substantially applied on electrochemical applications for their exceptional electrocatalytic ability and electric conductivity. Among the doping elements, electron-deficient boron (B) is considered to be a promising heteroatom for the chemical doping of carbon materials to modify the chemically inert sp2 carbon structure and thus activate the abundant free‐flowing π electrons. In this study, B-doped carbon nanotubes (BCNTs) with various boron doping atomic percentages (0.40–3.92 at%) are synthesized and used as a electrocatalyst on the counter electrode (CE) of dye-sensitized solar cells (DSSCs) for investigating the effect of boron doping on carbon materials. A solar-to-electricity conversion efficiency (η) of 7.17 ± 0.11% is achieved for a DSSC with a CE containing BCNTs with optimized B doping concentration (BCNT-0.40 at%), which is higher than that of the cells with CEs consisting of pristine carbon nanotubes (CNT, η = 5.98 ± 0.20%) and is comparable to that of the cell with a Pt CE (η = 7.98 ± 0.05%). It is also noteworthy from a practical viewpoint that the developed atmospheric-pressure synthesis method for synthesizing BCNT is amenable to industrial-scale production since a requirement for vacuum system can be avoided.

In order to find new sources of natural antioxidants, total phenolic content (TPC) and total flavonoid content (TFC) of 30 flowers in their free, esterified and insoluble-bound forms were determined. Rosa rugosa Thunb (pink) showed the highest TPC, and Osmanthus fragrans had the highest TFC. The antioxidant activities of 30 flowers were determined by 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH), ferric reducing antioxidant power (FRAP), and trolox equivalent antioxidant capacity (TEAC) assays. Rosa rugosa Thunb (purple) and Rosa rugosa Thunb (pink) had the highest DPPH (612.79 and 544.75 μmol Trolox/g DW), FRAP (273.10 and 301.14 μmol Trolox/g DW) and TEAC (1013.71 and 937.19 μmol Trolox/g DW) value. Furthermore, several phenolic compounds were detected using ultra performance liquid chromatography (UPLC) technique, and (+)-catechin, ferulic acid, isoquercitrin, and quercitrin were widely found in these flowers. The results implied that the flowers were important natural sources of bioactive components with higher antioxidant capacities for use in the food and pharmaceutical industries.

An atmospheric pressure, solution-assisted substitution process has been developed to produce boron-doped carbon nanotubes (BCNTs) with tunable boron dopant concentrations precisely from atomic percent of 0.4–3.9% by controlling the reaction conditions. The systematic material characterizations and detailed electrochemical sensor applications were studied. The electrochemical detection of dopamine (DA) can be improved by the enhanced electrocatalytic activity and reduced electron transfer resistance of BCNTs due to the boron doping. The effects of boron dopant concentrations on the electrocatalytic activity and electron transfer resistance of the BCNTs were investigated thoroughly in this study. It was found experimentally that the anodic peak current density (ipa) of DA is the highest (169.6 ± 8.9 μA cm−2) on the BCNTs (B 2.1 at.%) modified screen printed carbon electrode (SPCE). In this study, we have successfully developed a highly efficient and tunable synthesis of BCNTs in bulk quantities as the potential electrocatalysts for DA oxidation reaction. Also, it is noteworthy from a practical point of view that the developed atmospheric-pressure BCNTs synthesis method is amenable to industrial-scale production since it avoids the need for a vacuum system.

Developing highly planar semiconducting polymer is essential for achieving high mobility and improving the photovoltaic performance of bulk-heterojunction polymer solar cells. In this contribution, two novel low-bandgap donor-acceptor copolymers, P1-3T and P2-3T2F, consisting of electron-accepting benzothiadiazole acceptor segment and electron-donating terthiophene donor segment with and without fluorine atoms were designed and synthesized. The density functional theory calculations and ultraviolet–visible absorption studies demonstrate that the fluorinated P2-3T2F polymer has more planar backbone conformation, deeper HOMO level, broader absorption spectrum with a vibronic shoulder peak, and higher absorption coefficient compared with the non-fluorinated analogue polymer, P1-3T. Furthermore, P2-3T2F exhibits good crystallinity and high hole mobility, presumably due to the well-ordered lamellar packing and the π-π stacking interaction between the backbones of the conjugated polymers. The optimized polymer solar cell based on P2-3T2F:PC61BM exhibits a short-circuit current density (Jsc) of 12.77 mA cm−2, a fill factor (FF) of 68.99%, an open-circuit voltage (Voc) of 0.80 V, and a maximum power conversion efficiency (PCE) of 7.14%, which is approximately 46% higher than that of the P1-3T:PC61BM device. The enhanced PCE is primarily due to increased light-harvesting ability and interconnected morphology with finely dispersed polymer-rich and PC61BM-rich domains, which improves the efficiency of exciton dissociation and rises the mobility of charge carriers, thus boosting the short-circuit current density and the FF value. Moreover, the relatively deep HOMO of P2-3T2F effectively increases the Voc.

In this study, γ-alumina and zeolite ZSM-5 were used as catalysts to examine their effects on the pyrolysis of castor meal. The operation conditions for the pyrolysis were a pyrolytic temperature of 400 °C, residence time of 120 min, heating rate of 20 °C/min, and nitrogen flow rate of 200 mL/min. With the addition of catalysts, significant variations in pyrolytic products was observed, and the presence of γ-alumina and zeolite ZSM-5 slightly reduced the pyrolytic oil yield. However, the thermal analysis results demonstrate that the catalysts changed the pyrolysis mode and enhanced the hydrogenation/deoxygenation reaction and removed oxygen as CO, CO 2 , and H 2 O. Gas chromatography-mass spectrometry, elemental analysis, and viscosity analysis were also performed. With the addition of catalysts, the pyrolytic oil consisted of lighter compounds. The viscosity of the pyrolytic oil decreased significantly, and its viscosity index and calorific value increased. Therefore, catalytic pyrolysis can improve the quality of pyrolytic oil, and adding γ-alumina decreases the pyrolysis temperature from 339 °C to 284 °C. In addition, for the deoxygenating ability, the effect of γ-alumina will be greater than that of zeolite ZSM-5.

A polymeric dispersant is usually used for preparing the uniform multiwalled carbon nanotubes (CNT) film for replacing Pt as the catalyst on the counter electrode (CE) of dye-sensitized solar cells (DSSCs). However, it is necessary to remove the polymeric dispersant completely due to its nonconductive property. Herein, boron-doped CNT (BCNT) with enhanced thermal stability, as the benefit to the dispersant removal, was prepared as the catalyst on the CE of a DSSC, and the cells with pristine CNT and Pt as the catalyst on the CEs were compared. The BCNT based DSSC shows the best light-to-electricity conversion efficiency (η) of 7.91 ± 0.21%, which is higher than that of the cell with a CNT CE (η = 6.02 ± 0.19%) and is comparable to that of the cell with a Pt CE (η = 8.03 ± 0.11%).

Development of composite material parts requires significant research and development effort. The fiber size, volume fraction and direction are important in determining the properties of the part. Additive manufacturing (AM) methods are increasingly used for printing composite materials. Advancements in 3D scanning and imaging technology have raised a significant concern in reverse engineering of parts made by AM, which may result in counterfeiting and unauthorized production of high quality parts. This work is focused on using imaging methods and machine learning to reverse engineer a composite material part, where not only the geometry is captured but also the tool path of 3D printing is reconstructed using machine learning of microstructure. A dimensional accuracy with only 0.33% difference is achieved for the reverse engineered model.

The sonogram is currently an effective cancer screening and diagnosis way due to the convenience and harmlessness in humans. Traditionally, lesion boundary segmentation is first adopted and then classification is conducted, to reach the judgment of benign or malignant tumor. In addition, sonograms often contain much speckle noise and intensity inhomogeneity. This study proposes a novel benign or malignant tumor classification system, which comprises intensity inhomogeneity correction and stacked denoising autoencoder (SDAE), and it is suitable for small-size dataset. A classifier is established by extracting features in the multilayer training of SDAE; automatic analysis of imaging features by the deep learning algorithm is applied on image classification, thus allowing the system to have high efficiency and robust distinguishing. In this study, two kinds of dataset (private data and public data) are used for deep learning models training. For each dataset, two groups of test images are compared: the original images and the images after intensity inhomogeneity correction, respectively. The results show that when deep learning algorithm is applied on the sonograms after intensity inhomogeneity correction, there is a significant increase of the tumor distinguishing accuracy. This study demonstrated that it is important to use preprocessing to highlight the image features and further give these features for deep learning models. In this way, the classification accuracy will be better to just use the original images for deep learning.

In recent years, the issue of environmental pollution is more and more important. Some people may drive the car to sparsely populated areas and throw a lot of garbage near rivers, which will cause serious environmental pollution. So, the official organizations have to deploy temporary cameras to monitor human activities in these areas. Many commercial surveillance solutions can be deployed; but the cost is too high to be deployed at wilderness. In addition, the environment of the wilderness is too complex, and the traditional solution is not capable for the scenario. In this paper, we design a real-time and low-cost license plate recognition system on embedded platform, which can be deployed at roadside for temporary monitoring. The system can adjust different algorithms to fit different situations to recognize the license plate. In the experimental results, the overall recognition accuracy of the license plate number is 87%.

Hydrogen peroxide (H 2 O 2 ) is an essential mediator for most of the oxidative biological reactions in enzyme-based biosensor systems, such as glucose oxidase, cholesterol oxidase, and alcohol oxidase. Synthesis of new catalysts to detect the concentration of H 2 O 2 more precisely is indispensable for enzyme-based electrochemical biosensors. In this study, boron-doped graphene nanosheets (BGNs) with 2.2 atomic percentage (at%) boron doping level and a hierarchical microstructure were synthesized by an atmospheric-pressure carbothermal reaction as a noble-metal free catalyst for sensing H 2 O 2 . The isolated boron atoms on the BGNs surface act as the electrocatalytic sites by transferring charges to neighbor carbon atoms, and the hierarchical microstructure provides multidimensional electron transport pathways for charge transfer and therefore enhances the electrocatalytic ability. BGNs possess a higher reduction current in the cyclic voltammetry (CV) measurement than that of pristine graphene nanosheets (GNs) over the detection range of 0.0 to 10.0 mM at −0.4 V ( vs. Ag/AgCl). The BGNs modified electrochemical sensor shows a linear range from 1.0 to 20.0 mM of H 2 O 2 with a sensitivity of 266.7 ± 3.8 μA mM −1 cm −2 and limit of detection (LOD) of 3.8 μM at a signal-to-noise (S/N) ratio of 3. The beneficial hierarchical microstructure and the synergetic effects arising from doping boron in GNs accomplish the better performance of the BGNs modified electrochemical sensor.

This study analyzes the tribological performance of the test results of the journal bearing wear tester designed for the simulation of the toggle pin motion in the plastics injection molding machine. Grease with or without the addition of ultra-dispersed nanodiamond (UDD) particles were all tested in the durability tests. It showed that the grease with UDD additive could effectively extend the life of grease more than twice as long as the grease life without UDD additive in the reciprocating heavy-load and low-speed journal bearing tests.

We present a two-step postgrowth substitution reaction route to produce boron-doped carbon nanotubes (BCNTs) with controllable B dopant concentration and uniform B atom distribution under atmospheric pressure. The unique two-step postgrowth substitution reaction route comprised a simple wet-chemistry-assisted pretreatment and an atmospheric-pressure carbothermic reaction. Extensive materials characterizations confirmed that BCNTs with uniform B dopant distribution and controllable B atomic concentration from 0.40 to 3.92 atomic percent (atom%) can be produced by controlling the reaction time and temperature under atmospheric pressure in the developed method. The film-based electrical sheet resistance measurement indicates that the averaged electrical sheet resistances of the as-fabricated CNT-based films can be improved from 1520 ± 197.56 to 43.67 ± 12.63 Ω per square with 2.09 atom% B concentration in the doped CNTs. High-resolution X-ray photoelectron spectroscopy (HRXPS) characterization suggests that the B–C–O bonding types and concentrations in the as-produced BCNTs may play an important role in the nanotube electrical properties. Our study provides a methodology to tailor the material properties of carbon-based materials.

In this research, the Zn(C5H7O2)2·xH2O-based growth of ZnO micro/nanostructures in a low temperature, vapor-trapped chemical vapor deposition system was attempted to optimize structural and optical properties for potential biomedical applications. By trapping in-flow gas molecules and Zinc vapor inside a chamber tube by partially obstructing a chamber outlet, a high pressure condition can be achieved, and this experimental setup has the advantages of ease of synthesis, being a low temperature process, and cost effectiveness. Empirically, the growth process proceeded under a chamber condition of an atmospheric pressure of 730 torr, a controlled volume flow rate of input gas, N2/O2, of 500/500 Standard Cubic Centimeters per Minute (SCCM), and a designated oven temperature of 500 °C. Specifically, the dependence of structural and optical properties of the structures on growth duration and spatially dependent temperature were investigated utilizing scanning electron microscopy, X-ray diffraction (XRD), photoluminescence (PL), and ultraviolet-visible transmission spectroscopy. The experimental results indicate that the grown thin film observed with hexagonal structures and higher structural uniformity enables more prominent structural and optical signatures. XRD spectra present the dominant peaks along crystal planes of (002) and (101) as the main direction of crystallization. In addition, while the structures excited with laser wavelength of 325 nm emit a signature radiation around 380 nm, an ultraviolet lamp with a wavelength of 254 nm revealed distinctive photoluminescence peaks at 363.96 nm and 403.52 nm, elucidating different degrees of structural correlation as functions of growth duration and the spatial gradient of temperature. Transmittance spectra of the structures illustrate typical variation in the wavelength range of 200 nm to 400 nm, and its structural correlation is less significant when compared with PL.