Among the products of the electrocatalytic reduction of carbon dioxide (CO2RR), CO is currently the most valuable product for industrial applications. However, poor stability is a significant obstacle to CO2RR. Therefore, we synthesized a series of bimetallic organic framework materials containing different ratios of tungsten to copper using a hydrothermal method and used them as precursors. The precursors were then subjected to pyrolysis at 800 °C under argon gas, and the M-N bimetallic sites were formed after 2 h. Loose porous structures favorable for electrocatalytic reactions were finally obtained. The material could operate at lower reduction potentials than existing catalysts and obtained higher Faraday efficiencies than comparable catalysts. Of these, the current density of WCu-C/N (W:Cu = 3:1) could be stabilized at 7.9 mA ‧ cm-2 and the FE of CO reached 94 % at a hydrogen electrode potential of -0.6 V (V vs. RHE). The novel materials made with a two-step process helped to improve the stability and selectivity of the electrocatalytic reduction of CO2 to CO, which will help to promote the commercial application of this technology.

사범대학 학생은 대학생일 뿐만 아니라 미래의 교사로서 자신의 핵심 소양을 향상시킬 뿐만 아니라 학생의 핵심 소양을 발전시키는 중요한 책 임을 져야 한다. 본 논문의 연구 목적은 사범생의 직업적 인식이 핵심 소양에 미치는 영향을 조사하는 것이다. 연구 방법은 정량적 연구 방법 과 SPSS 26.0 통계 소프트웨어를 사용하여 데이터를 분석하였다. 연구 결과는 사범생의 직업 정체성과 핵심 소양 사이에 유의미한 정적 상관관 계가 있음을 보여주며, 직업적 정체성의 각 차원은 핵심 소양에 예측 효 과가 있는 것을 보여 주었다. 이 연구를 통해 우리는 사범생의 핵심 소 양 형성에 영향을 미치는 요인과 메커니즘을 찾고 사범생의 인재 양성과 기초 교육 발전을 향상시키기 위한 이론적 참고 자료를 제공한다.

Moso bamboo, as a kind of renewable functional material, exhibits outstanding development potential. It is promising to prepare activated carbon with good mechanical strength and high specific surface area using moso bamboo as raw material. In this work, we employed a hydraulic extruder to extrude the bamboo charcoal and the adhesive to obtain the moso bamboo activated carbon, and improved the specific surface area of the columnar activated carbon through high-temperature water vapor activation. Through the catalytic role of the water vapor activation process, the formation and expansion of the pores were promoted and the internal pores were greatly increased. The obtained columnar activated carbon shows excellent mechanical strength (93%) and high specific surface area (791.54 m2/ g). Polyacrylamide@asphalt is one of the most effective adhesives in the high-temperature water vapor activation. The average pore size (22.99 nm) and pore volume (0.36 cm3/ g) of the prepared columnar activated carbon showed a high mesoporous ratio (83%). Based on the excellent pore structure brought by the activation process, the adsorption capacity of iodine (1135.75 mg/g), methylene blue (230 mg/g) and carbon tetrachloride (64.03 mg/g) were greatly improved. The resultant moso bamboo columnar activated carbon with high specific surface area, excellent mechanical properties, and outstanding adsorption capacity possesses a wide range of industrial applications and environmental protection potential.

With the wide application of portable wearable devices, a variety of electronic energy storage devices, including microsupercapacitors (MSCs), have attracted wide attention. Laser-induced graphene (LIG) is widely used as electrode material for MSCs because of its large porosity and specific surface area. To further improve the performance of MSCs, it is an effective way to increase the specific surface area and the number of internal active sites of laser-induced graphene electrode materials. In this paper, N-doped polyimide/polyvinyl alcohol (PVA) as precursor was used to achieve in situ doping of nitrogen atoms in laser-induced graphene by laser irradiation. Through the addition of N atoms, nitrogen-doped laser-induced threedimensional porous graphene (N-LIG) exhibits large specific surface area, many active sites, and good wettability all of which are favorable conditions for enhancing the capacitive properties of laser-induced graphene. After assembly with PVA/H2SO4 as gel electrolyte, the high surface capacitance of the MSC device with N-LIG as electrode material is 16.57 mF cm− 2 at the scanning rate of 5 mV s− 1, which is much higher than the 2.89 mF cm− 2 of the MSC device with LIG as electrode material. In addition, MSC devices with N-LIG as electrode materials have shown excellent cyclic stability and flexibility in practical tests, so they have a high application prospect in the field of flexible wearable microelectronics.

Pyrolysis of methane is a carbon-economic method to obtain valuable carbon materials and COx- free H2, under the carbon peaking and carbon neutrality goals. In this work, we propose a methane pyrolysis process to produce graphite and H2 using bubble column reactor containing NiO/Al2O3 and NaCl–KCl (molten salt). The process was optimized by the different amounts of NaCl–KCl, the CH4/ Ar ratio and temperature, indicating that the CH4 conversation rate could reach 92% at 900 °C. Meanwhile, we found that the addition of molten salt could obtain pure carbon materials, even if the conversation rate of CH4 decreases. The analysis of the carbon products revealed that graphite could be obtained.

인도 태평양 지역의 지정학적 긴장이 고조됨에 따라 안보 연구에서 쿼 드의 중요성이 점점 더 커지고 있다. 이 글에서는 일본이 쿼드를 다시 주창하기로 한 원인을 살펴본다. 연구에 따르면 쿼드에 대한 일본의 입 장은 쿼드의 소다자주의적 특성과 일본의 국내 정치라는 두 가지 요인에 의해 영향을 받는 것으로 나타났다. 소다자주의적 특성은 쿼드가 일본이 참여하기에 '편리한' 플랫폼이라는 점을 시사하며, 국내 정치 측면에서는 아베 총리가 두 번의 임기 동안 주장한 가치 외교가 쿼드와 잘 부합한다 는 점을 드러낸다. 결과적으로 쿼드는 일본에게 실질적인 지정학적 '도구 '로 기능하고 있다.

In this paper, iron ore tailings (IOT) were separated from the tailings field and used to prepare cement stabilized macadam (CSM) with porous basalt aggregate. First, the basic properties of the raw materials were studied. Porous basalt was replaced by IOT at ratios of 0, 20 %, 40 %, 60 %, 80 %, and 100 % as fine aggregate to prepare CSM, and the effects of different cement dosage (4 %, 5 %, 6 %) on CSM performance were also investigated. CSM’s durability and mechanical performance with ages of 7 d, 28 d, and 90 d were studied with the unconfined compression strength test, splitting tensile strength test, compressive modulus test and freeze-thaw test, respectively. The changes in Ca2+ content in CSM of different ages and different IOT ratios were analyzed by the ethylene diamine tetraacetic acid (EDTA) titration method, and the micro-morphology of CSM with different ages and different IOT replaced ratio were observed by scanning electron microscopy (SEM). It was found that with the same cement dosage, the strengths of the IOT-replaced CSM were weaker than that of the porous basalt aggregate at early stage, and the strength was highest at the replaced ratio of 60 %. With a cement dosage of 4 %, the unconfined compressive strength of CSM without IOT was increased by 6.78 % at ages from 28 d to 90 d, while the splitting tensile strength increased by 7.89 %. However, once the IOT replaced ratio reached 100 %, the values increased by about 76.24 % and 17.78 %, which was better than 0 % IOT. The CSM-IOT performed better than the porous basalt CSM at 90 d age. This means IOT can replace porous basalt fine aggregate as a pavement base.

This study explores the histological features and Bmp4 expression patterns in the replaced tooth germ of Xenopus laevis . Tooth germ formation starts from the dental placode through epithelial-mesenchymal interactions, involving various signaling pathways such as Fgf, Shh, Bmp, and Wnt. In mice, Bmp4 expression in the dental placode inhibits Pax9 expression in the dental mesenchyme. Although absent in the presumptive dental lamina of birds and toothless mammals, Bmp4 remains conserved in reptiles and fish owing to gene duplication. However, its expression in amphibian tooth germs is poorly understood. Three-month-old X. laevis were employed in this study. Initially, samples underwent paraffin embedding and were sectioned into 5 or 12 μm ribbons for H&E staining and in situ hybridization, respectively. Results revealed teeth appearing in two maxillary rows: the labial side, with prefunctional and functional teeth, and the lingual side, with replaced tooth germs behind functional teeth. Enameloid was observed between the inner dental epithelium and dental mesenchyme at the cap or early bell stages, whereas enamel and dentin formed during the late bell or mineralization stages from the replaced tooth germ. Bmp4 expression was evident in the inner dental epithelium (ameloblasts), dental papilla (odontoblasts), stellate reticulum, and Hertwig’s epithelial root sheath. Overall, these findings highlight the conservation of Bmp4 expression in X. laevis tooth development.

Cu2+/polyacrylonitrile composite fibers were prepared by electrospinning, and then Cu/carbon nanofibers (denoted as Cu/ CNF-X; X = Cu content, 0, 3, or 5 wt%) were formed by calcining them. The effects of Cu2+ content and carbonization temperature on the conductivity and electrothermal conversion of Cu/CNF-X were investigated. The results revealed that the conductivity and electrothermal properties of Cu/CNF-X improve with the increase in the Cu2+ content and carbonization temperature. When the carbonization temperature was 800, 900, or 1000 °C, the conductivity of Cu/CNF-5 (0.08, 0.68, or 2.48 S/cm, respectively) increased to 1.6, 1.5, or 1.6 times that of Cu/CNF-0, respectively. The highest instantaneous surface temperatures of Cu/CNF-5 calcined at 800, 900, and 1000 °C (36, 145, and 270.2 °C, respectively) increased by 4, 25.5, and 44.6 °C, respectively, compared with those of the corresponding Cu/CNF-0 samples (32, 120.3, and 225.6 °C, respectively). Thus, the addition of a small amount of Cu2+ effectively improved the conductivity and electrothermal conversion performance of Cu/CNF-X, which has potential application value in industrial products in the future.

Heavy metal ions pollution has become of worldwide critical concern, thus, it is particularly important to monitor it in the environment and food for ensuring human health. In this study, p-phenylenediamine and 2-mercaptothiazoline were used to prepare nitrogen (N) and sulfur (S) co-doped carbon dots (N/SCDs) for fluorescent and colorimetric detection of Cu2+. The fabricated N/SCDs with bright green fluorescence showed excellent optical characteristics and favorable water solubility. In an aqueous system, a significant fluorescence quenching of N/SCDs at 512 nm is obtained in the presence of Cu2+. It also caused a significant colorimetric response with the color of prepared N/SCDs solution changed from colorless to yellow. Under optimal conditions, the analytical results showed that the linear range spanning from 5 to 400 μM, with a detection limit of 0.215 μM in fluorescence and 0.225 μM in colorimetric detection. In addition, N/SCDs displayed high selectivity toward Cu2+. No obvious interference was observed over other metal ions. Furthermore, we have also used N/SCDs to monitor Cu2+ in tap and lake water. The recovery of Cu2+ ranged between 89.6% and 113.1%. Exhibiting remarkable sensitivity and selectivity, the designed sensor offers a promising detection method for Cu2+ detection in the real sample.

Graphene-modified melamine sponges (RGO-MSs) were prepared, as adsorbents with photothermal conversion ability, utilizing solar energy to achieve heavy oil temperature rise, viscosity reduction, and efficient adsorption recovery of highly viscous oil. The RGO-MSs were prepared through a simple impregnation method. The photothermal performance and heavy oil adsorption performances of RGO-MSs with different densities and thicknesses were observed. It was found that as the density increases, the thermal conductivity of RGO-MS increases too, leading to the increase of the average oil absorption rate. The reduction of thickness is beneficial to improving of the adsorption rate. The prepared RGO-MS with a density of 21.5 mg/cm−3 and a height of 1 cm (RGO-MS-3-1) shows excellent mechanical properties and fatigue resistance. Cyclic adsorption–desorption of RGO-MS-3-1 was achieved through extrusion/ ethanol washing. After 10 cycles of reuse through extrusion, the adsorption capacity decreased from 52.90 to 50.02 g g− 1, with a loss of 5.4%. The material was then washed with petroleum ether and ethanol in turn. Its adsorption capacity can restored to 98.8% of the initial value, showing a promising application prospect on heavy oil leakage treatment. The easily prepared RGO-MS exhibits excellent light absorption and photothermal oil adsorption properties, providing a good solution for the problem of heavy oil leakage at sea.

A series of ZIF-67-C-IL catalysts were prepared using ZIF-67 and 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl] imide ([ BMIM]NTf2) ionic liquid as precursors. The structure of the catalysts was characterized by XRD, TEM, SEM and XPS. The catalytic performance of the catalysts for the oxygen reduction reaction (ORR) was evaluated in a three-electrode system. The results confirmed that the high-temperature treatment of the precursors resulted in the formation of N, S codoped carbon-encapsulated Co9S8 nanoparticles. To create N, S co-doped carbon coated Co9S8 nanoparticle catalysts, ionic liquids are used as sulfur and nitrogen sources. The catalytic activity of ORR can be improved using N, S co-doped carbon to prevent the aggregation of Co9S8 nanoparticles. Graphitized and N, S co-doped carbon shells are optimal for achieving high activity stability. Optimal 600-ZIF-67-C(1:1.5)-30IL catalytic activity was observed for ORR. The half-wave potential of ORR was 0.88 V vs. RHE in 0.1 mol L− 1 KOH, with a limit current density of 4.70 mA cm− 2. Similar ORR electrocatalytic activity was observed between this catalyst and commercial Pt/C (20 wt%).

Background: The abdominal drawing-in maneuver (ADIM), a method of lumbar stabilization training, is an effective neuromuscular intervention for lumbar instability associated with low back pain (LBP). Objects: The purpose of this study was to compare the effect of a 2-week period of the ADIM and tensor fasciae latae-iliotibial band (TFL-ITB) self-stretching on lumbopelvic rotation angle, lumbopelvic rotation movement onset, TFL-ITB length, and pain intensity during active prone hip lateral rotation. Methods: Twenty-two subjects with lumbar extension rotation syndrome accompanying shortened TFL-ITB (16 males and 6 females) were recruited for this study. The subjects were instructed how to perform ADIM training or ADIM training plus TFL-ITB self-stretching program at home for a 2-week period. A 3-dimensional ultrasonic motion analysis system was used to measure the lumbopelvic rotation angle and lumbopelvic rotation movement onset. An independent t-test was used to determine between-group differences for each outcome measure (lumbopelvic rotation angle, lumbopelvic rotation movement onset, TFL-ITB length, and pain intensity). Results: The results showed that ADIM training plus TFL-ITB self-stretching decreased the lumbopelvic rotation angle, delayed the lumbopelvic rotation movement onset, and elongated the TFL-ITB significantly more than did ADIM training alone. Pain intensity was lower in the ADIM training plus TFL-ITB self-stretching group than the ADIM training alone group; however, the difference was not significant. Conclusion: ADIM training plus TFL-ITB self-stretching performed for a 2-week period at home may be an effective treatment for modifying lumbopelvic motion and reducing LBP.

Since Dolichovespula kuami Kim & Yoon was first recorded in Korea in 1996, there has been ongoing debate over its valid specific status. However, through recent analysis of the male genitalia structure and DNA barcode, it has been proven that it is a different species from D. flora Archer, which live in China. D. kuami is an endemic species that mainly lives in forest areas in the central and northern parts of South Korea. It is a hornet species that is relatively rare due to low nest density. Therefore, little is known about their ecological characteristics. However, as numerous wasps of D. kuami were recently collected in the Jilin Province of China, their distribution records have been confirmed to be beyond the Korean Peninsula to China. Therefore, this study aims to record the distribution of D. kuami in China for the first time.