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Investigation of operating parameters for carbon dioxide conversion using a Non-Thermal Plasma system
No full textIn recent years, the increasing concentration of CO2 has had a destructive impact on ecosystems. According to statistics, CO2 accounts for approximately 55% of the total annual anthropogenic greenhouse gas emissions causing global warming. As a result, continuous research has been conducted on the removal and conversion of CO2. The difficulty in converting CO2 lies in overcoming the molecule's high stability and requiring a significant amount of energy to break the double bonds. The high reactivity and utility of the resulting CO have made the conversion of CO2 to CO a topic of sustained interest and research.
This study employed the Dielectric Barrier Discharge (DBD) technique within the Non-Thermal Plasma (NTP) technology for CO2 conversion. Response surface methodology (RSM) was utilized to identify the optimal parameter combinations yielding the highest efficiency. The significance of various operating parameters (carrier gas, inlet concentration, inlet flow rate, and inlet humidity) on CO2 conversion efficiency, CO yield, and CO selectivity was analyzed using SPSS 28 (Statistical Product and Service Solutions 28) software. The results showed that the best results among all parameter combinations were achieved under the following operating conditions: N2 as the carrier gas, 15% CO2 inlet concentration, the total flow rate of 0.02 L/min, 10%RH inlet humidity, plasma discharge power of 24.5 W, and a residence time of 6.3 seconds. The achieved values were a CO2 conversion rate of 15.34%, CO yield of 14.72%, and CO selectivity of 95.96%. Under the same operating conditions, increasing the inlet concentration to 20% resulted in the optimal energy efficiency of 0.52%. It was observed that reducing inlet humidity and lowering the inlet flow rate had a positive impact on the CO2 conversion rate and CO yield. Regarding the carrier gas, using atmospheric air as the carrier gas had a negative effect on the conversion rate, possibly due to the influence of atmospheric water vapor content, which aligns with the findings on inlet humidity in this study. Additionally, introducing hydrogen into the carrier gas mixture resulted in the production of trace amounts of hydrocarbons. Furthermore, this study utilized solar power for supplying electricity to the Non-thermal plasma reactor, leading to near-zero energy cost under ideal conditions, providing a cost advantage compared to other Non-thermal plasma CO2 conversion techniques studied in the literature
\ue2 Everything Will Come True \ue2: The Effect of Psychological Test Advertisement on Sharing Intention.
No full textIn recent years, there has been a growing trend of psychological test advertisements on social media platforms which are shared by consumers to other users. These ads utilize the psychological mechanism of consumers to achieve marketing objectives. The customized test results and the product information that brand wants to put in constitute the primary presentation of psychological test advertisements. This makes it even more crucial to match the appropriate results of test content and embedded product information. Therefore, the aim of this study is to clarify the operational mechanisms between the narrative result orientation that influences the Barnum effect, the types of purchase products, and the driving force of consumer word-of-mouth within advertisements. The study also seeks to understand their impact on social media sharing intention. Moreover, self-congruence is introduced as a moderating variable to delve deeper into the significance of consumer psychological self-awareness in relation to advertising content.
This research used an experimental method, consisting of a pre-test, a pilot test, and a formal experiment. The sample comprises consumers aged 20 and above with experience in browsing social media platforms and consumer capability. A total of 542 valid questionnaires were collected. The findings reveal that: (1) Positive narrative orientation (compared to negative narrative orientation) triggers higher Barnum effect and word-of-mouth motivation. (2) The product nature of embedded products doesn\ue2t impact word-of-mouth motivation. (3) Positive narrative outcomes embedded in experiential purchase products generate the highest sharing intention through impression management. (4) When material purchase products are embedded and consumers perceive low levels of actual self-congruence, narrative orientation significantly influences word-of-mouth motivation. These results contribute to the fields of viral marketing, social media advertising, and word-of-mouth. The research also provides theoretical insights and practical recommendations for marketers in terms of combining and presenting elements in psychological test advertisements
An exploratory study on quiet quitting
No full text\ue3\ue3"Quiet Quitting" is a trending term that emerged in 2022, referring to the phenomenon where employees continue to work at a company but only fulfill the basic job requirements. They are reluctant to work overtime or invest extra effort and resist the culture of overwork, advocating for a balance between work and life.
\ue3\ue3Given the absence of relevant research on Quiet Quitting, this study conducted interviews with 11 individuals who self-identified as Quiet Quitters. The aim was to understand their observable work behaviors, underlying reasons, resulting impacts, and potential mitigation strategies.
\ue3\ue3The research findings indicated the following characteristics of self-identified Quiet Quitters:
1.They meet the minimum job quality requirements.
2.They don't proactively engage in non-routine tasks or new projects, but are willing to do so if requested by superiors.
3.They explicitly resist opportunities for promotion from their supervisors.
4.They often engage in self-initiated work optimizations to enhance personal work efficiency.
5.Their responses in terms of working overtime, responding to work messages during personal time, participating in further education, and interacting with supervisors vary based on their career plans, job satisfaction, and intentions to stay with the organization.
6.The reasons behind Quiet Quitting include a lack of job fulfillment, a desire for work-life balance, high work-related stress, inability to connect with supervisors or organizational culture.
7.Strategies to mitigate this phenomenon include open communication with employees and adjusting their job responsibilities
Applying non-linear equalization technique in duobinary amplitude modulation based on micro-ring modulators
No full textWith the development of science and technology, the demand for Internet traffic and high-speed computing in data centers is growing rapidly. In order to pursue higher-speed computing and greater bandwidth, one of the intuitive methods is to integrate more photonic devices into a unit volume, implying the reduction in the size of components. Leveraging silicon photonic technologies, a micro-ring modulator (MRM) can be made in the micron level, making it possible to realize an integrated optical transceiver with a small size. However, the use of a MRM for modulation needs to overcome some issue, including insufficient bandwidth and nonlinear distortion and resistor mismatch.
In the realm of signal transmission, investigating the reflection effects on micro-ring modulators reveals pronounced variations at the response. Duobinary offer a narrower bandwidth compared to pulse amplitude modulation (PAM) signal, effectively compensating for the narrower bandwidth of micro-ring modulators. Furthermore, duobinary demonstrate lower susceptibility to noise and transmission losses compared to pulse amplitude modulation signals. Since duobinary operate at the response, where micro-ring modulators exhibit significant nonlinear effects, receiving signal are subject to nonlinear interference.
To counter the nonlinear impact of micro-ring modulator at the response, Volterra filter is employed for compensation. Notably, when compared with non-return-to-zero (NRZ) and pulse amplitude modulation 4-level(PAM4), signals closer the response exhibit more distinct reflection effects. By comparing the quality factor before and after Volterra filter compensation, the impact of the effects on quality factor evident
Political-Economic Impacts of China\ue2s Hydropower Dams on the Mekong River Riparian States: Thailand, Lao PDR, Cambodia, and Vietnam
No full textThe Mekong River is one of the most diverse ecosystems in the world. It flows through six countries starting from China to Vietnam before it reaches the South China Sea. The river plays a very important role in keeping economic activities that support the livelihood of millions of people living on its banks. Apart from utilizing the river for agricultural economic activities, China came up with construction projects of hydropower dams upstream in order to meet its internal energy needs. However, the hydropower dams in China have posed severe socio-economic impacts on the environment, the livelihood of people, and the Mekong River itself. This study aims to understand the power relation between China and the Mekong River Commission member states by employing the theory of Hegemonic Stability to explain the relationship among all actors in the Greater Mekong Subregion. The study concludes that the economic power of China, which includes its military strength, and the MRC member states\ue2 need for development have stabilized China\ue2s hegemonic status in the Greater Mekong Subregion
Education for ocean literacy: SWOT analysis and strategies recommendation
No full textThe ocean is one of the Earth's vital resources, yet it is facing increasing threats such as pollution, overfishing, and climate change. Achieving ocean sustainability has become a crucial global issue. Taiwan, being surrounded by the sea on all sides, is an island nation, yet there is a significant lack of awareness and concern for the ocean among its citizens. Therefore, implementing comprehensive ocean literacy education is a pivotal step towards achieving ocean sustainability. Improving ocean literacy education requires concerted efforts from various stakeholders, including government support, educational institutions, and active participation from the general public, to ensure the deepening and widespread dissemination of ocean literacy education.
United Nations Sustainable Development Goal 14 emphasizes the protection of marine ecosystems, ensuring the sustainable use of marine resources, preserving the cultural value of the ocean, and nurturing an ocean-friendly mindset. By cultivating ocean literacy among the general population, increasing awareness and concern for ocean issues, we can collectively protect marine ecosystems, ensure the sustainable use of marine resources, and establish a shared consensus. Only through the cultivation of ocean education will it receive the attention and importance it rightfully deserves.
To begin, we conducted a literature review using keywords such as "ocean literacy," "ocean education," and "ocean literacy education" to understand their definitions and the current development status both domestically and internationally. This allowed us to grasp the trends and further explore the future policy development of ocean literacy education. This study primarily referenced the National Marine Educators Association's (NMEA) K-12 Ocean Literacy Scope and Sequence Guide, ocean education policy white papers, and the 2020 Ocean Policy White Paper.
Grounded in scientific theory, we focused on enhancing post-education ocean literacy and informal education for the general public. We utilized SWOT and TOWS analyses to examine the internal strengths and weaknesses, as well as external opportunities and threats of Taiwan's ocean literacy education policy. Through TOWS analysis, we matched the internal and external environments to determine how to leverage strengths and opportunities to mitigate or avoid weaknesses and threats. This analysis will provide insights into the strategies needed for ocean literacy education in Taiwan. Additionally, we highlighted the importance of ocean literacy education by drawing on relevant international literature and experiences in cultivating and implementing ocean literacy education abroad, aiming to shift the public's relationship with the ocean
A dual-network ionic gel based on poly acrylic acid/gelatin/silver nitrate/Vitamin C for promotion of wound healing
No full textThe skin is the largest organ in the human body, serving as the first line of defense against foreign objects and protecting against invasion while also regulating moisture, facilitating perspiration, providing warmth, and sustaining the senses. However, due to extended exposure to external elements, the skin is highly susceptible to injury, with wounds often resulting in scarring, which can have significant impacts on individual patients and healthcare economics. In the United States, the cost of wound healing annually amounts to 12 billion. Patients with genetic diseases, diabetes, and older adults are particularly vulnerable to abnormal wound healing, which can result in long-term sequelae, even requiring amputations. Thus, researchers are striving to develop materials for protecting injured skin from infection. Although traditional dry dressings, such as cotton, gauze, and bandages, are critical for the initial phase of wound healing, they lack the ability to provide a moist environment for the wound and often adhere to the dry wound surface, causing pain and trauma upon removal. To overcome these disadvantages, we have developed a DES-Gelatin dressing based on deep eutectic solvents (DES) , with added gelatin, silver nitrate, vitamin C, and cross-linkers that exhibit high biocompatibility, mechanical strength, antimicrobial, and anti-inflammatory properties to facilitate wound healing. Rheological, swelling, tensile, antibacterial, antioxidant, vitamin C, cytotoxicity, cell proliferation, and migration tests were performed ex vivo. Finally, a rat wound healing model was employed, where DES-Gelatin dressings were applied to the wound, with results demonstrating nearly complete wound closure by the eleventh day of treatment and control wounds remaining unhealed. Overall, the experiment is simple, cost-effective, and demonstrates that DES-Gelatin dressings exhibit a broad range of functions and performance, making them a promising material for promoting wound healing in the future
Research on \uce\ub1-Gallium Oxide Epitaxy on C- M- R- Plane of Sapphire Substrate for Deep Ultraviolet Photodetectors and Schottky Barrier Diodes
No full textIn this study, \uce\ub1-gallium oxide (\uce\ub1-Ga2O3) thin films were epitaxially grown using mist chemical vapor deposition (Mist-CVD). We investigated the suitable growth temperatures on different orientations of C-M-R-planes of sapphire substrates for achieving single-crystal \uce\ub1-Ga2O3 films. Additionally, we examined the optoelectronic response characteristics of \uce\ub1-Ga2O3-based ultraviolet (UV) photodetectors with embedded doping and their impact on Schottky diodes.
To gain a deeper understanding of the single-crystal structure, film electron concentration, energy bandgap values, and atomic arrangements of \uce\ub1-Ga2O3, we employed various analytical tools, including (1) X-ray diffraction, (2) Hall effect measurements, (3) ellipsometry, and (4) transmission electron microscopy. Initially, X-ray diffraction confirmed that sapphire substrates with C-M-R-planes can support the growth of single-crystal \uce\ub1-Ga2O3 films at temperatures of 450\uc2\ub0C, 600\uc2\ub0C, and 600\uc2\ub0C, respectively. Subsequent Hall effect measurements provided information on the film's electron concentration and carrier mobility under different doping levels. Furthermore, ellipsometry revealed slight variations in the energy bandgap of \uce\ub1-Ga2O3 grown on different planes of the substrate. Finally, transmission electron microscopy observations provided insights into the atomic arrangement, d-spacing, and selected-area diffraction patterns, conclusively confirming the single-crystal structure of the thin films.
Regarding UV photodetectors, we harnessed the wide energy bandgap of \uce\ub1-Ga2O3 to detect deep ultraviolet (UV-C) light. We compared the impact of embedded doping on the electrical and optoelectronic properties of the devices. Our results indicated that the dark current of the devices could differ by up to 109 times before and after doping. Furthermore, the responsivity and external quantum efficiency increased significantly by factors of 104 and 105, respectively.
In the case of Schottky diodes, we achieved Ohmic and Schottky contacts by leveraging the differences in work functions between various metals and the film, along with annealing processes. Additionally, we adjusted the level of embedded doping to attain switch characteristics with an on-off ratio of 105. Breakdown voltage tests conducted on sapphire substrates with C-M-R-planes showed that the devices could withstand voltages exceeding 3000 volts
Using Chaotic Map Based Coefficient Scrambling Scheme and Syntax Element Encryption for H.265/HEVC Video Encryption
No full textHigh efficiency video coding (H.265/HEVC) is a commonly used video coding standard today. To protect the privacy of video content, much research has proposed H.265/HEVC video selective encryption schemes. Since the coefficient scrambling scheme proposed in recent years is still not safe, a coefficient scrambling scheme based on chaotic maps is proposed. With the help of the pseudo-randomness of chaotic maps, the distribution of coefficients can be effectively disturbed to improve the randomness of coefficient scrambling. At the same time, in H.265/HEVC, there are some coefficient coding methods that can effectively improve the efficiency of coding coefficients, so the coefficient scrambling conditions are also planned to exclude these coefficients from coefficient scrambling, so that the coefficient scrambling operation doesn\ue2t affect a lot of bit rate overhead. Coefficient scrambling combined with syntax element encryption, including motion vector difference (MVD) information (mvd_sign_flag, abs_mvd_minus2 suffix), quantized transform coefficient (QTC) information (coeff_sign_flag, coeff_abs_level_remaining suffix) and luma intra prediction mode (Luma IPM) information, can effectively destroy video content to ensure privacy protection. The proposed scheme is synchronized with slices to ensure that the decrypted video content will not be affected after losing some slices. In addition, the random sequence generated by AES-CTR is associated with the H.265 encoded stream to resist chosen plaintext attacks. Experimental results show that the proposed scheme has the characteristics of high security, format compliant, fast execution time, synchronous update with slice, and resistance to common attacks, etc., and effectively improves the bit rate overhead of coefficient scrambling. Therefore, the proposed scheme can provide a better choice for H.265/HEVC video selection encryption scheme
Effect of electrolyte composition and processing parameters on electrodeposition behavior of zinc on copper substrate
No full textThis study aims to investigate the influence of electroplating conditions and substrate grain orientation on the microstructure and deposition mode of Zn deposited on polycrystalline Cu substrate in two electrolyte systems: an acidic zinc sulfate solution and an alkaline Zn(OH)42- solution. The primary experimental parameters include concentration/pH of plating electrolyte and current density. The morphology of the zinc coating was examined using scanning electron microscopy, and electron backscatter diffraction was employed to analyze the crystal orientations of the copper grains and the overlaid zinc layers to characterize their epitaxial orientation relationships (EORs). The quality of epitaxy is further characterized using the kernel average misorientation (KAM) method.
The experimental results indicated that the 1 \uc2\ub5m Zn layers deposited in solution containing 2 M zinc sulfate at pH of 2 or 3 were all polycrystalline, while their counterparts deposited at pH of 4 or 5 grew epitaxially on all substrate grains except the ones having an orientation of //ND. Two EORs have been identified as (0001)Zn //(111)Cu, [-1-120]Zn//[1-10]Cu, and (1-101)Zn //(001)Cu, [11-20]Zn//[1-10]Cu. Further study indicated that the current density also plays an important role on epitaxial growth of Zn. At 10 mA/cm2, epitaxy was allowed only on grains of //ND, //ND and //ND, but the layers deposited on all grains were epilayers at 70 mA/cm2 or above. The epitaxial growth were maintained as the layers were as thick as 50 \uef\uadm. Reducing the zinc sulfate concentration in the plating solution from 2 M to 0.5 M resulted in a decrease in the epitaxial grain size to approximately 300 nm, and an increase in the plating solution pH led to a higher defect density within the epitaxial layer. Additionally, epitaxial growth remained unattainable on substrate grains with Cu //ND orientation.
The results of the alkaline solution was different. The Zn layers deposited in an epitaxial mode in a 5 M NaOH solution at a low current density of 10 mA/cm2. Conversely, it was found that the overlaid Zn layers on most substrate grains were epitaxial only when they were deposited in a 1 M NaOH solution at a high current density of 100 mA/cm2. Coatings deposited in the 5 M NaOH solution exhibited lower defect densities than those in the 1 M NaOH solution. In the 1 M NaOH solution, the crystalline size of zinc within the deposited coating was reduced to approximately 200 nm. In the 5 M NaOH solution, a additional EOR was identified for layers deposited on the Cu //ND substrate grains as (0001)Zn //(001)Cu and [11-20]Zn//[1-10]Cu.
Using coatings deposited in a 2 M zinc sulfate plating solution at pH 4, charge/discharge simulations were conducted. The experimental results indicated that, with a fixed discharge rate of 5 mA/cm2, when a high charging rate of 70 mA/cm2 was employed, the coating maintained epitaxial growth after ten cycles. However, when a low charging rate of 10 mA/cm2 was used, the coating's surface formed a structure resembling dendritic crystals