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Owing to its rapidity and accuracy, near-infrared (NIR) spectroscopy is a powerful tool to establish appropriate prediction models with an innovative method to evaluate wood properties. To reveal the mechanical qualities of clonal Chinese fir woods and to determine sound prediction models of mechanical properties, four main mechanical properties of six Chinese fir clones (Yang 020, Yang 061, Kaihua 3, Kaihua 13, Daba 8, Kailin 24) were evaluated by NIR spectroscopy. The clones Kaihua 13, Kailin 24, and Yang 020 showed good mechanical properties. To estimate mechanical properties with NIR spectroscopy, different methods should be adopted for different properties. The average spectra of radial and tangential sections combined with multiple scattering correction (MSC) and Savitzky-Golay (S-G) smoothing methods were used to predict the modulus of rupture and modulus of elasticity. By adopting cross section spectra and taking MSC and S-G smoothing methods for pretreatment, the models of compressive strength parallel to grain could deliver the best results. For wood hardness, the models established with average spectra of three sections and first- derivative method were preferred. The correlation coefficients of the prediction models were between 0.84 and 0.90, and those of the calibration models were between 0.75 and 0.96. Key words: Chinese fir, clones, mechanical properties, near-infrared spectroscopy, rapid prediction. A cause de sa rapidite et de sa precision, la spectroscopie dans le proche infrarouge (SPIR), est un outil puissant pour etablir des modeles de prediction appropries avec une methode innovante pour evaluer les proprietes du bois. Dans de but de deceler les caracteristiques mecaniques du bois de clones de sapin chinois et d'elaborer des modeles valables de prediction des proprietes mecaniques, quatre proprietes mecaniques importantes de six clones de sapin chinois (Yang 020, Yang 061, Kaihua 3, Kaihua 13, Daba 8, Kailin 24) ont ete evaluees avec la SPIR. Les clones Kaihua 13, Kailin 24 et Yang 020 avaient de bonnes proprietes mecaniques. Pour estimer les proprietes mecaniques avec la SPIR, on devrait adopter differentes methodes en fonction de chaque propriete. Les spectres moyens des sections radiale et tangentielle combines a la correction de la diffusion multiple (CDM) et aux techniques de lissage de Savitzky-Golay (S-G) ont ete utilises pour predire les modules de rupture (MOR) et d'elasticite (MOE). En adoptant les spectres de la section transversale et en utilisant les techniques de CDM et de lissage de S-G pour le pretraitement, les modeles de resistance a la compression parallele au grain pouvaient donner les meilleurs resultats. Dans le cas de la fermete du bois, on preferait les modeles etablis avec les spectres moyens de trois sections et la methode de la premiere derivee. Les coefficients de correlation des modeles de prediction variaient entre 0,84 et 0,90 et ceux des modeles d'etalonnage allaient de 0,75 a 0,96. [Traduit par la Redaction] Mots-cles: sapin chinois, clones, proprietes mecaniques, spectroscopie dans le proche infrarouge, prediction rapide., Introduction Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) is a coniferous tree species with the shortest growth period in China and has been widely used in construction, furniture, and ship industries [...]

FePMo12O40@PVP composite materials were synthesized with the regulation of polyvinylpyrrolidone (PVP) to control the structure. The samples were characterized by FT-IR, XRD, XPS, SEM, TEM and UV-Vis DRS. The composite retains the Keggin-type polyoxometalates structure, exhibiting a high specific surface area that enhances photon capture efficiency. Analysis of UV-Vis DRS absorption band edge and band gap indicated that the composite was responsive to visible light. Photocatalytic degradation of Rhodamine B (RhB) by FePMo12O40@PVP was investigated under commonly used LED light source, demonstrating excellent photocatalytic performance as 2.5 g-FePMo12O40@PVP (0.015 g) can remove 83% of RhB (10 mg/L) in 40 min. The FePMo12O40@PVP composite material demonstrated sustained moderate degradation efficiency even after undergoing three cycles of repeated use. The non-covalent interaction and strong interfacial coupling between PVP and FePMo12O40 promoted the transfer of h+, and e−, ∙O2−, ·OH, and h+ served as the primary active species in this photocatalytic system. This environmentally friendly material has the potential to significantly reduce energy consumption and offers valuable insights for the future treatment of dye wastewater. [ABSTRACT FROM AUTHOR]

Polarization detection has been widely used in various fields, especially in free-space optical communication associating with orbital angular momentum (OAM). However, the bulky optical devices and the complexity of the detection process have hindered the integration and miniaturization of communication systems. Herein, a novel polarization detection method is proposed to directly identify the polarization state of incident light based on the normalized spectra of the sorted OAM modes which are converted from a composite vortex beam (CVB) to a set of spatial distinct strip type beams (STBs). The polarization states of light beam can be apparently distinguished via the combination of different STBs without redundant detection elements and the system demonstrates great robustness under specific atmospheric turbulence as well. The introduction of such a polarization detection method in future communication links will obtain lower complexity and consumption, which is very favorable regarding OAM communications. [ABSTRACT FROM AUTHOR]

With the development of multilingual information on the Internet, how to effectively represent the infor-mation contained in different language texts has become an important sub-task of natural language information processing. Therefore, cross-lingual word embedding has become a hot technology. Cross-lingual word embedding can be mapped to a shared low-dimensional space with the help of transfer learning, and the grammar semantic and struc-tural features can be transferred between different languages, which can be used to model cross-lingual semantic infor-mation. By training a large number of corpora, a general word embedding is obtained in BERT (bidirectional encoder representations from transformers) model, which is further dynamically optimized according to specific downstream tasks to generate context-sensitive word embedding, thus solving the aggregation problem of previous models and obtaining dynamic word embedding. Based on the literature review of the existing cross-lingual word embedding based on BERT studies, this paper comprehensively describes the development of cross-lingual word embedding learning based on BERT learning methods, models and techniques, as well as the required training data. According to different training methods, it is divided into two categories, supervised learning and unsupervised learning. And the representative research of the two types of methods is compared and summarized in detail. Finally, the evaluation methods of cross-lingual word embedding are summarized, and the prospect is made by studying the cross-lingual word embedding of Mongolian and Chinese based on BERT.

Pygmalion Effect, or Robert Rosenthal Effect, was proved by the famous American psychologist Robert Rosenthal and Jacobson in 1968. Pygmalion Effect, as a matter of fact, is a psychological suggestion, which believes that people can accept the influence and suggestion given by the people whom very much they admire, like, believe, and respect. This effect was first applied in the field of management and medication. What's more, remarkable achievements have been accomplished on human resource management. Robert Rosenthal put it into education through an experiment called "Pygmalion in the Classroom," which aroused widely attention in the education sector. This thesis mainly focuses on the application of Pygmalion effect in English teaching, especially junior English teaching in China. If we can make good use of the Pygmalion Effect to conduct teaching and have positive expectations to students, it will improve teaching greatly.

In this paper, polyamine-functionalized carbon dots (CDs) were synthesized by means of low temperature (<100°C) carbonization of citric acid at the presence of polyethylenimine (PEI), resulting spherical calcium carbonate micro-particles from inverse micro-emulsion system. Nanoscaled spherical silicas were prepared by Stöber method via deposition on the surface of micron calcium carbonate. Scanning- and transmission-electron microscopic analysis confirmed a micro-/nano-complex structure, enabling the composite material coating possessed coarser surface similar to those of 'lotus leaf'. After modification with 1 H, 1 H, 2 H, 2 H-perfluorodecanethiol, both good super hydrophobicity and good fluorescent performance were confirmed by the water contact angle of 154.1°±1.5°, their surface-free energy, and fluorescence quantum yield of 14.1%, which provides an inexpensive and easy way to fabricate superhydrophobic material with fluorescence characteristics and promotes high value application of inorganic materials. [ABSTRACT FROM AUTHOR]

The supercritical CO2 (sCO2) power cycle could improve efficiencies for a wide range of thermal power plants. The sCO2 turbine generator plays an important role in the sCO2 power cycle by directly converting thermal energy into mechanical work and electric power. The operation of the generator encounters challenges, including high temperature, high pressure, high rotational speed, and other engineering problems, such as leakage. Experimental studies of sCO2 turbines are insufficient because of the significant difficulties in turbine manufacturing and system construction. Unlike most experimental investigations that primarily focus on 100 kW‐ or MW‐scale power generation systems, we consider, for the first time, a small‐scale power generator using sCO2. A partial admission axial turbine was designed and manufactured with a rated rotational speed of 40,000 rpm, and a CO2 transcritical power cycle test loop was constructed to validate the performance of our manufactured generator. A resistant gas was proposed in the constructed turbine expander to solve the leakage issue. Both dynamic and steady performances were investigated. The results indicated that a peak electric power of 11.55 kW was achieved at 29,369 rpm. The maximum total efficiency of the turbo‐generator was 58.98%, which was affected by both the turbine rotational speed and pressure ratio, according to the proposed performance map. [ABSTRACT FROM AUTHOR]

In this paper, polyamine-functionalized carbon dots (CDs) were synthesized by means of low temperature (<100°C) carbonization of citric acid at the presence of polyethylenimine (PEI), resulting spherical calcium carbonate micro-particles from inverse micro-emulsion system. Nanoscaled spherical silicas were prepared by Stöber method via deposition on the surface of micron calcium carbonate. Scanning- and transmission-electron microscopic analysis confirmed a micro-/nano-complex structure, enabling the composite material coating possessed coarser surface similar to those of 'lotus leaf'. After modification with 1 H, 1 H, 2 H, 2 H-perfluorodecanethiol, both good super hydrophobicity and good fluorescent performance were confirmed by the water contact angle of 154.1°±1.5°, their surface-free energy, and fluorescence quantum yield of 14.1%, which provides an inexpensive and easy way to fabricate superhydrophobic material with fluorescence characteristics and promotes high value application of inorganic materials. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) ceramic is being increasingly applied in several engineering fields owing to its excellent saturation electron drift rate. Although much attention is paid to its material removal mechanism, producing a high‐quality SiC surface with a high material removal rate is still a challenging issue. Therefore, there is a need to investigate the material removal mechanism of SiC to improve the processing performance. In this study, the laser heating‐assisted nanocutting models are established using a molecular dynamics method. Then, a laser beam with various energies is irradiated onto the SiC. The influence of average laser power on the nanocutting mechanism of SiC is revealed in terms of the temperature of the machined region, cutting force, stress distribution state, subsurface damage, and tool wear. The results demonstrate that within the scope of this study, the using of laser irradiation methods has a positive effect on the machinability of SiC at the nanoscale, provided that the laser power density does not exceed the ablation threshold. Meanwhile, the results indicate that laser heating‐assisted methods have played an important role in suppressing tool wear. This study has significant theoretical and practical value in processing technology. [ABSTRACT FROM AUTHOR]