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.
Single-atom Pd clusters anchored on t-BaTiO3 material was synthesized using hydrothermal and ultrasonic methods for the effective piezoelectric catalytic degradation of pollutants using vibration energy. XRD patterns of BaTiO3 loaded with monoatomic Pd were obtained before and after calcining, and showed typical cubic-phase BTO. TEM and HAADF-STEM images indicated single-atom Pd clusters were successfully introduced into the BaTiO3. The piezoelectric current density of the prepared Pd-BaTiO3 binary composite was significantly higher than that of the pristine BaTiO3. Under mechanical vibration, the nanomaterial exhibited a tetracycline decomposition rate of ~95 % within 7 h, which is much higher than the degradation rate of 56.7 % observed with pure BaTiO3. Many of the piezo-induced electrons escaped to the Pd-doped BaTiO3 interface because of Pd’s excellent conductivity. Single-atom Pd clusters help promote the separation of the piezo-induced electrons, thereby achieving synergistic catalysis. This work demonstrates the feasibility of combining ultrasonic technology with the piezoelectric effect and provides a promising strategy for the development of ultrasonic and piezoelectric materials.
Graphitic carbon nitride (g-C3N4) has attracted extensive attention in energy storage due to its suitable and tunable bandgap, high chemical/thermal stability, earth abundance and environmental friendliness. However, its conductivity should be improved to work as the electrode materials in supercapacitors. In this report, we have prepared a two-dimensional composite (CN-PANI) based on g-C3N4 and polyaniline (PANI) by in-situ polymerization, which can be efficiently applied as electrode material for supercapacitors. The introduction of PANI can increase the conductivity of the electrode, and the porous structure of g-C3N4 can provide enough channels for the transport of electrolyte ions and improve the electrode stability. As a result, the obtained CN-PANI demonstrates excellent specific capacitance (234.0 F g− 1 at 5 mV/s), good rate performance and high cycling stability (86.2% after 10,000 cycles at 50 mV/s), showing great potential for high-rate supercapacitors.
The carbon spheres (CSs) synthesized by an ultrasonic-spray pyrolysis method were activated for supercapacitor electrode. There are plenty of cracks on the surface of the activated carbon spheres (ACSs), which expend with increasing the activation temperature and activator dosage. The specific capacitance of ACSs increases with the activation temperature and activator dosage and reach to maximal value at certain conditions. Importantly, the ACS sample activated at relatively low activation temperature (600 °C) and 7 of mass ratio of KOH to CSs has the highest specific capacitance (about 209 F g− 1 at 50 mA g− 1 of current density) and indicates the excellent cycling stability after 1000 consecutive charge–discharge cycles. Furthermore, the graphene sheets could be found in the samples that were activated at 1000 °C. And the electrode prepared by the sample has the very low series resistance because of the excellent conductivity of the formed graphene sheets.
최근 중국에서는 많은 환경문제가 제기되어 왔으며 정부의 관심도 증가하여 특히, 난파물 제거작업에 대한 전반적인 접근방식에 큰 영향을 미쳐 왔다. 따라 서 대부분의 난파물 제거작업에 대해 환경적인 요소를 우선적으로 고려하며 진 행하게 되었다. 한편, 최근 시장경제 논리 경향에 따라 난파물 제거 작업에 대 한 정부당직의 단계별 비규제화를 보이는 부분도 있어 왔다. 이러한 상황에서 이 논문은 강제적인 난파물 제거와 관련된 전형적인 행정상 및 민사상 문제들을 명 확히 하고, 중국의 현행규정 상 논란이 되고 있는 규정에 대한 살펴보고자 한다. 아 울러 난파물 제거 비용에 대한 부분도 고찰해 보고자 한다.
While it was found that consumers’ experience on purchase intention is significantly affected by greater involvement in blogging (Hsu & Tsou, 2011), not many fashion companies use blogs to improve online consumption and relationship with their employee or customer (Fieseler & Fleck, 2013). Further, despite the growing significance of blog communication, there is a lack of understanding for the impact of accumulation of social capital in the blogosphere on the consumers’ attitude and engagement in previous research. This study is designed to address this gap, and particularly the role of three dimensions of social capital (i.e., structural, relational, and cognitive) in understanding blog user’s attitude and engagement. The purpose of this study is to investigate 1) the effect of blog user’s motivation (i.e., perceived usefulness, perceived ease of use, reputation, altruism, enjoyment, community identification) on their level of social capital within the blog 2) the influence of structural social capital and cognitive social on user’s relational social capital and 3) the impact of relational social capital on blog user’s attitude and engagement.
Data was collected through a marketing research firm utilizing online survey method.
With 530 usable data, the results of this study indicated enjoyment have positive
significant effect on structural social capital while community identification have
negative significant effect on structural social capital. For the effect of blogging
motivation on cognitive social capital, the result showed positive significant effect of
perceived usefulness, altruism and community identification on cognitive social capital
Further, structural social capital does not have relationship with relational social capital
while cognitive social capital has significant effect on relational social capital. The results
also indicated that the relational social capital has influence on blogging attitude, which
in turn has strong positive relationship with blogging engagement.
The findings of this study contribute some useful knowledge about fashion blog and the
relationships of the three social capital dimensions to the literature. Also, this study not
only provides theoretical insight into understanding the influence of fashion blog user’s
motivation on blogging behavior and satisfaction of needs of belong, it also exposes the
influence of relationships building in blog community on user’s blogging attitude and
engagement. Previous studies focused more on social influence on knowledge sharing
motivation, and most of the researchers paid attention to the interaction of cognitive social capital and relational capital. This study employs the knowledge sharing motivation findings of previous studies, and it uses the effective motivation factors to test if they have the same impacts on people’s blogging behavior.
Wood vinegar, an extract from Acer Tegmentosum Maximowicz, was evaluated for its hypoglycemic and anti-diabetic properties by using normal and diabetic rats. The extract was dissolved in water and administered daily for six or seven weeks. In experiment 1, thirty normal Sprague- Dawley (SD) male rats were randomly divided into five treatments of 6 rats each. The treatments were T1 (mineral water), T2 (mineral water), T3 (silver solution), T4 (wood vinegar), and T5 (silver solution + wood vinegar) and diabetes was induced by intravenous injection of streptozotocin except T1. In experiment 2, sixteen diabetic Goto-Kakizaki (GK) male rats were randomly divided into four treatments of 4 rats each. The treatments were T1 (mineral water), T2 (silver solution), T3 (wood vinegar), and T4 (silver solution + wood vinegar). Streptozotocin-induced diabetic rats showed less body weight gain, more food intake and less water consumption as compared with normal non-diabetic rats. Oral administration of wood vinegar resulted in more weight gain, lower blood glucose concentration and urine pH among all the diabetic rats. In experiment 2, diabetic GK rats administrated with wood vinegar showed higher weight gain, food intake and less water intake when compared with control. However, supplementation with wood vinegar did not result in any decrease of blood glucose concentrations. It could be concluded that wood vinegar extracted from Acer Tegmentosum Maximowicz exerted hypoglycemic effect in diabetic-induced normal rats, but not in diabetic GK rats.
A miniaturized CMOS bandpass filter for a single RF transceiver system is presented, using diagonally end-shorted coupled lines and lumped capacitors. In contrast to conventional miniaturized coupled line filters, it is proven that the effective permittivity variation of the coupled transmission line has no effect on shifting the center frequency when the bandpass filter is highly miniaturized. A bandpass filter at a center frequency of 2 GHz was fabricated by 0.18μm CMOS technology. The insertion loss with the die area of 1500μm×1000μm is -5.14 dB. Simulated results are well agreed with the easurements. It also verify the center frequency stability in the compact size bandpass filter.
In this letter, the effect of quality factor on center frequency deviation in miniaturized coupled line bandpass filter (BPF) with diagonally end-shorted at their opposite sides and lumped capacitors is theoretically analyzed. The miniaturized BPF of a two-stage structure with two types of quality factors in standard CMOS process was designed and manufactured at 5.5 GHz. The die area of BPF was 1.44×0.41 mm2. The measured center frequency of BPF with a quality factor of 4.9 was deviated from 5.5 GHz to 4.7 GHz. The one with 14.8 was shifted to 5GHz. The theoretical and measured results validate that quality factor influences the center frequency shift of BPF.