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.
In recent years, the efficient and clean utilization of coal has been widely concerned by scholars at home and abroad. Despite the abundance of global coal resources, the deep utilization rate of coal is still insufficient. To address this challenge, it has been explored the development and preparation of coal-based high value-added carbonaceous materials. In the present study, a novel process was developed for the preparation of graphene using biphenyl sourced from low-rank coal. Using chemical vapor deposition (CVD) technology, it was successfully implemented for us to grow high-quality graphene on copper foils. The prepared graphene products were observed and characterized using Raman spectroscopy, optical microscopy and scanning electron microscopy techniques. The results of this research provide a new perspective for the utilization of low-rank coal resources.
The presence of tetracycline (TC) has been detected in the human living environment, and its complex structure makes it difficult to degrade. The green and efficient utilization of electroactivated persulfate advanced oxidation technology for the degradation of tetracycline remains a challenge. In this study, N-doped reduced graphene oxide (N-rGO) was prepared using a hydrothermal treatment method with urea as the nitrogen source. Four different mass ratios of graphene oxide (GO) to urea were synthesized, and the optimal mass ratio was determined through degradation experiments of tetracycline. The N-rGO/EC/PMS three-dimensional electrocatalytic system was constructed, and the influence of the experimental data on TC degradation, such as initial pH, PMS dosage and voltage, was determined. Characterization analysis using scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and other methods was conducted. The efficient catalytic ability of N-rGO was demonstrated through the generation of hydrogen peroxide ( H2O2) and consumption of peroxymonosulfate (PMS). The superiority of the three-dimensional (3D) electrochemical advanced oxidation process was proposed by combining different systems. Furthermore, the presence of hydroxyl radicals (.OH), persulfate radicals ( SO4 ·−), and singlet oxygen (1O2) was identified using electron spin resonance (ESR) technology. The utilization of N-rGO as a three-dimensional electrode, coupled with the advantages of PMS activation and electrochemical oxidation processes, is a promising method for treating organic pollutants in wastewater.
The challenge of incorporating photothermal conversion function into chitosan (CS) hybrid fibers lies in balancing functionality and mechanical properties. In this study, we successfully prepared a chitosan/graphene oxide/gelatin (CS/GA/GO) hybrid fiber using the wet spinning process, achieving improved mechanical properties and efficient photothermal conversion capabilities. When compared with pure CS fiber with a breaking strength of 1.07 cN/dtex, the breaking strength of the CS/ GA composite fiber increased by 46.73%, while the CS/GA/GO hybrid fiber showed an even greater increase of 85.98%. In addition, the introduction of gelatin (GA) led to secondary scattering of near-infrared light, enhancing the photothermal conversion efficiency. As a result, the CS/GA/GO hybrid fiber exhibited a faster temperature rise rate and higher maximum temperatures (94.3 °C, 103.0 °C, and 111.3 °C) as compared to the CS/GO hybrid fiber. The successful incorporation of GA not only improved the mechanical properties but also enhanced the photothermal performance of the hybrid fiber.
Polylactic acid (PLA) is often used in the preparation of environmentally friendly biodegradable polymer plastics, and how to improve the flame retardant performance of polylactic acid has been concerned by experts and scholars. Here, we provide a new idea, using bamboo activated carbon as the main material, and phytic acid, urea and Zn(NO3)2·6(H2O) as modifiers to produce a new type of carbon flame retardant. It has bamboo activated carbon as carbon source; second, it has P, N elements and metal oxides. The two synergistically play a flame retardant role on polylactic acid. The polylactic acid composite showed good thermal stability, from no grade optimization to V-0 in the UL-94 test, and the limiting oxygen index was also increased from 20.1 to 31.2%. The above tests show that bamboo activated carbon loaded with ZnO has a good flame retardant effect on polylactic acid.
In this work, the trend in the performance of carbon fiber (CF) and its composite during self-polymerization of polydopamine (PDA) at carbon fiber surface was investigated by varying the self-polymerization time of dopamine in an aqueous solution. Research has shown that the PDA coating elevated the surface roughness and polarity of the inert fiber. The tensile strength of single carbon fiber was significantly improved, especially after 9 h of polydopamine self-polymerization, increasing by 18.64% compared with that of desized carbon fiber. Moreover, the interlaminar shear strength (ILSS) of CF-PDA9-based composites was 35.06% higher than that of desized CF-based composites. This research will provide a deep insight into the thickness and activated ingredients of dopamine oxidation and self-polymerization on interfacial compatibility of carbon fiber/epoxy resin composites.
High-quality diamond films have attracted extensive attentions due to their excellent optical and electrical properties. However, several issues, such as random orientation, stress accumulation, and slow growth rate, severely limit its applications. In this paper, high-quality polycrystalline diamond films with highly ordered (100) orientation were prepared by microwave plasma chemical vapor deposition. The effects of growth parameters on the microstructure, quality and residual stress of diamond films were investigated. Experimental results indicate that relatively high temperature at low methane concentration will promote the formation of (100) oriented grains with a low compressive stress. Optimized growth parameters, a methane concentration of 2% along with a pressure of 250 Torr and temperature at 1050 ℃, were used to acquire high growth rate of 7.9 μm/h and narrow full width at half maximum of Raman peak of 5.5 cm− 1 revealing a high crystal quality. It demonstrates a promising method for rapid growth of high-quality polycrystalline diamond films with (100) orientation, which is vital for improving the diamond related applications at low cost.
Natural enemy insects, including predators and parasitoids, are beneficial organisms that feed upon other agricultural pests. Using natural enemy insects to suppress or prevent outbreak of pests is a key component of integrated pest management strategy. It is safe, effective, and environmentally friendly and can be applied easily to the greenhouses, filed crops and orchards. Rearing and application of natural enemy insects in biocontrol in China have a long history. As early as 1700 years ago, the predator Oecophylla smaragdina has been used for controlling many kinds of citrus pests. Up to now, more than 30 species of natural enemies that can be artificially mass produced and widely used for biological control of many kinds of pests, including caterpillars, aphids, whiteflies, thrips, leaf mites and scales in China. The annual average application area of natural enemies is over 11.34 million hectares. However, with the increasing demand of using natural enemies in biological control programs, the development of natural enemy insect industrialization still face many challenges. It is urgent to explore more effective candidate natural enemies, improve the production efficiency, increase the shelf life of products and enhance the colonization of natural enemy insects after release, and thus facilitate the commercially production and application of natural enemies. This is of great significance for comprehensively promoting the use of green prevention and control techniques for crop diseases and pests, reducing the use of chemical pesticides, ensuing the quality and safety of food and agricultural products, and ultimately promoting sustainable agricultural development.
Some digital platforms introduced a novel positive-framing design in the multi-dimensional rating system, which framed the attribute with positive words for consumers to rate. The results from a cross-platform quasi-natural experiment show that the positive-framing design can increase the rating scores compared with the traditional non-positive framing design.
In recent years, the trend of customer demand and personalization has become more and more obvious. The previous innovation model can no longer meet the diversified needs of consumers. Therefore, firms vigorously develop open innovation to promote internal and external innovation (von Hippel, 1988). With the rapid development of AI technology, open innovation communities have more interactions with the users. Organizations continue to rely on their open innovation community to collect innovative ideas from non-professional customers and then integrate them into their new product development process to produce innovative products that are more in line with customer preferences (Bayus, 2013). At present, the research on user design focuses on how to increase user design implementation and the idea popularity (Yang et al., 2022; Zhang et al., 2022). Few studies discussed how to motivate consumers to participate in innovative content output from the source. In addition, academic research on user design is mostly limited to management comments, lacking in-depth empirical research (Franke et al. 2008). Previous studies have proved that the number of leading users in the open innovation community is far less than that of non-leading users (Hofstetter et al., 2018), so it is very necessary to improve the willingness of users to participate in community creative activities. With the vigorous development of the new technology, it is an urgent problem to be solved to encourage users to participate in innovation activities and improve the innovation performance of firms (Chesbrough, 2012). Today, firms pay more and more attention on the implementation of AI technology. With AI and user design as the research background, “AI recommendation” and “willingness to design” as the key variables, and the “S-O-R model” and “Self-determination Theory” as the basis, this paper deeply explores whether AI recommendation can be used as a factor affecting user’s participation in design activities from the perspective of users, focusing on the intermediary role of user’s inspiration, competency and self-expression. It also puts forward that product involvement and aesthetic experience openness (Donghwy and Youn, 2018) are the boundary conditions that affect user’s willingness to participate in design. The results show that user’s willingness to participate in design is higher when providing AI recommedation, and the sense of inspiration, competence and self-expression play a mediating role in it. Furthermore, the results show that when product involvement is high, users are more willing to participate in design. Similarly, users with a high degree of aesthetic experience openness are more willing to participate in design activities. This study enriches the theory of enterprise community management, promote the internal information flow of the open innovation community, and provide theoretical guidance and reference for firms to optimize the new product design process.
지능형 컴퓨팅의 등장으로 빅데이터를 활용한 패션 브랜드 의미 마이닝과 가치 홍보에 초점을 맞춘 새로운 연구 트렌드가 등장하였다. 본 연구의 목적은 인기 여성복 브랜드 5개를 대상으로 다양한 종류의 의류에 대한 소비자 감성 트렌드를 조사하는 것이다. 유니클로, 에이치스타일, 베로모다, 피스버드, 온리. 이를 위해 총 93,550건의 소비자 평가를 수집하고, 키스멧 감성 분석 엔진을 활용하여 의류 유형별 감성 극성도를 분석하였 다. 그 결과, 브랜드에 따라 감정 극성이 크게 다르다는 것을 알 수 있었으며, HSTYLE 후드티, ONLY 니트웨 어, 피스버드 순면, 유니클로 니트가 각각 소비자들에게 가장 강한 긍정적 감정을 불러일으켰다. 또한 이번 연 구에서는 각 브랜드에서 가장 인기 있는 의류 유형과 착용 효과를 밝혀 패션 기업이 효과적인 마케팅 전략을 수립하고 제품 제공을 강화하는 데 중요한 인사이트를 제공했다. 이러한 연구 결과를 바탕으로 게임 업계에서 는 감성 분석을 적용하여 다양한 게임 브랜드, 장르, 게임 플레이에 대한 플레이어의 감정 반응을 이해하고 게임 프로모션 전략과 제품 디자인 개발에 도움을 줄 수 있다. 전반적으로 이 연구 결과는 디자인 분야에서 빅데이터의 잠재력을 입증하고 업계에서 경쟁 우위를 확보하기 위해 빅데이터를 활용하는 것이 중요하다는 점을 강조할 수 있다.
One-step hydrothermal reduction method was used to prepare three-dimensional carbon fiber brush-based graphene–platinum (CFB/Pt–G) composites to improve the electrocatalytic oxygen reduction activity of cathode materials for seawater oxygen-dissolved battery. Characterization results show that the reduced graphene oxide of as-prepared graphene–platinum composite displays the few-layer folded structure. In addition, Pt nanoparticles with the polycrystalline structure dispplay a preferential growth along the crystal plane of (111) and are mainly distributed around the defect cavities of folded graphene. Electrochemical results show that the diffusion-limited current density of CFB/Pt–G composite tested with 1600 rpm/min in 3.5% NaCl solution reaches 5 mA/cm2, while that of CFB/G is only 2.64 mA/cm2. Battery discharge results show that the maximum volume power density of CFB/Pt–G–Mg battery with a stable open voltage of 1.73 V is 81 times as much as the commercial seawater battery SWB1200.
High-performance carbon materials were prepared via a one-step molten salt carbonization of tobacco waste used as electrode materials for supercapacitors. Carbon material prepared by carbonization for 3 h in molten CaCl2 at 850 °C exhibits hierarchically porous structure and ideal capacitive behavior. In a three-electrode configuration with 1 mol L− 1 H2SO4 aqueous solution, it delivers specific capacitance of 196.5 F g− 1 at 0.2 A g− 1, energy density of 27.2 Wh kg− 1 at 0.2 A g− 1, power density of 983.5 W kg− 1 at 2 A g− 1, and excellent cyclic stability with 94% capacitance retention after 5000 charge–discharge cycles at 1 A g− 1. Moreover, in a symmetrical two-electrode configuration with 6 mol L− 1 KOH aqueous solution, it delivers specific capacitance of 111.1 F g− 1 at 0.2 A g− 1, energy density of 3.8 Wh kg− 1 at 0.2 A g− 1, and power density of 482.0 W kg− 1 at 2 A g− 1. The relationship between hierarchically porous structure and capacitive performance is also discussed.
In this study, nitric acid oxidation with varied treatment temperature and time was conducted on the surfaces of polyacrylonitrile- based ultrahigh modulus carbon fibers. Scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and surface tension/dynamic contact angle instruments were used to investigate changes in surface topography and chemical functionality before and after surface treatment. Results showed that the nitric acid oxidation of ultrahigh modulus carbon fibers resulted in decreases in the values of the crystallite thickness Lc and graphitization degree. Meanwhile, increased treating temperature and time made the decreases more obviously. The surfaces of ultrahigh modulus carbon fibers became much more activity and functionality after surface oxidation, e.g., the total surface energy of oxidized samples at 80 °C for 1 h increased by 27.7% compared with untreated fibers. Effects of surface nitric acid oxidation on the mechanical properties of ultrahigh modulus carbon fibers and its reinforced epoxy composites were also researched. Significant decreases happened to the tensile modulus of fibers due to decreased Lc value after the nitric acid oxidation. However, surface treatment had little effect on the tensile strength even as the treating temperature and processing time increased. The highest interfacial shear strength of ultrahigh modulus carbon fibers/epoxy composites increased by 25.7% after the nitric acid oxidation. In the final, surface oxidative mechanism of ultrahigh modulus carbon fibers in the nitric acid oxidation was studied. Different trends of the tensile strength and tensile modulus of fibers in the nitric acid oxidation resulted from the typical skin–core structure.
Low thermal conductivity carbon fibers from polyacrylonitrile (PAN) are currently being explored as an alternative for traditional rayon-based carbon fibers with a thermal conductivity of 4 W/m K. Compared to multiple component electrospinning, this research demonstrated another feasible way to make low thermal conductivity carbon fibrous material by electrospinning PAN followed by carbonization and alkali activation. The effects of activation condition on microstructure, pore formation, and thermal conductivity of the resultant carbon nanofibrous material were investigated. The processing-structure-thermal conductivity relationship was revealed and mechanism of thermal conductivity reduction was discussed. The overall thermal conductivity of the prepared carbon nanofibrous material is a result of combined effects from factors of carbon structure and number of pores rather than volume of pores or specific surface area. The activated carbon nanofibrous materials showed thermal conductivity as low as 0.12 W/m K, which is a reduction of ~ 99% when compared to that of solid carbon film and a reduction of ~ 95% when compared to that of carbon nanofibrous material before activation.
Energy and environmental are always two major challenges for the sustainable development of the modern human being. For avoiding the serious environmental pollution caused in the fabrication process of porous carbon, a popular energy storage material, we reported a facile, green and activating agent free route hereby directly carbonizing a special biomass, Glebionis coronaria. A nitrogen doped hierarchical porous carbon with a specific surface area of up to 1007 m2 g−1 and a N doping content of up to 2.65 at.% was facilely fabricated by employing the above route. Benefiting from the peculiarly hierarchical porous morphology, enhanced wettability and improved conductivity, the obtained material exhibits superior capacitance performance, which capacitance reaches up to 205 F g−1 under two-electrode configuration, and no capacitance loss is observed after 5000 cycles. Meanwhile, the capacitance retention of the obtained material arrives up to 95.0% even under a high current density of 20 A g−1, illuminating its excellent rate capability. The fabricated nitrogen-doped hierarchical porous carbon with larger capacitance than commercial activated carbon, excellent rate capability and cycle stability is an ideal cost-efficient substitution of commercial activated carbon for supercapacitor application.
A new deformation micromechanism operating in the carbon cathode for aluminum electrolysis termed a ripplocation has been proposed in this paper. The creep deformation of semi-graphitic cathode was measured using a modified Rapoport equipment at 965 °C with cryolite ratio = 4.0. The characteristic of the defect was obtained by analyzing TEM photograph of the carbon cathode with different testing times. The results indicated that basal dislocations, bulk ripplocations, kink bands and delamination cracks appeared in succession in the first two stages of the creep deformation. Ripplocations in the carbon cathode make a layer of carbon atoms to glide relative to each other without damaging the in-plane bonds. Ripplocations could also attract each other and result in kink boundaries. The creep strain of the carbon cathode could be accommodated by kink band and delamination cracks during aluminum electrolysis. A more comprehensive understanding of their micromechanics behaviors is very important and could deeply influence our current knowledge of the deformation mechanism of the carbon cathode for aluminum electrolysis.
Despite the recent promising findings on the influence of social media engagement on brand performance outcomes (e.g., De Vries & Carlson, 2014), researchers suggest that consumer engagement in social media sites requires a deeper understanding (Islam & Rahman, 2016). To respond to this call, we conducted this research to examine an important, yet under-researched, question on the underlying mechanism by which consumer engagement on social media drive improved brand performance. In this research, we develop and empirically test a conceptual model to investigate the relationships among consumer engagement, psychological brand ownership, brand loyalty, brand performance, and consumer’s word of mouth (WOM) in the context of social media. The findings suggest that consumer engagement influences brand outcomes through its indirect impact on consumers’ psychological ownership of the brand. When consumers engage themselves with the brand at social media sites, they tend to form bonds with the brand and develop a sense of community, of which they feel they are a part. Feelings of ownership motivate consumers to care for and nurture the growth of the brand, which manifests itself in terms of brand loyalty, positive word of mouth, and improved brand performance. The focus of consumer engagement in social media communities provides convincing evidence to support the benefits of using social media to connect with consumers. This research offers promising insights on how relationship with a brand can help create sense of community and feelings of ownership among consumers, which in turn drives better brand performance.