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.

The 1982 United Nations Convention on the Law of the Sea admitted legislation and enforcement jurisdiction carried out by the flag state. However, the emergence of substandard ships and the growing number of ship accidents at sea indicate that flag state jurisdiction is far from effective. Four aspects of these failures are examined in this paper. Confronted with the failure of flag state jurisdiction, port states have devised a subsidiary remedy to ensure their national interests and restore the effectiveness of flag state jurisdiction. A problem hereunder arises because non-explicit permission was given to port states to prosecute substandard ships. Thus, this paper further analyses four aspects of port state jurisdiction. The authors aim to analyse the failures and remedies associated with state jurisdiction over ships. It reviews the scope and deficiency of state jurisdiction in combatting substandard ships and illicit activities at sea. This paper also addresses the importance of port state control, regional memorandums of understanding and international conventions.

21세기 초부터 중국의 해외관광산업이 많이 활발해졌고, 운남성도 이러한 배경 하에 주변국가와 관광산업분야에서 협력의 폭과 깊이를 넓힐 수 있었다. 중국-미얀마 경제회랑은 중국이 설립 된 두 번째 무역회랑이며 이는 란창-메콩 지역발전에 중요한 역할을 하고 있다. 학술계는 운남 및 미얀마 양측의 관광산업을 중심으로 한 협력이 더욱더 활성화 될 거라고 전망하고 있다. 본 논문은 중국-미얀마 경제 회랑 건설을 기반으로 중국 Dehong지역과 미얀마 간의 관광산업협력 현황 및 협력 메커니즘, 인프라 구축, 국경 간 관광 상품 개발 및 관광 서비스 등을 분석하였고, 또한 Dehong과 미얀마 간 관광 협력에 적합한 친환경적인 협력모델을 탐색하였다.

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.

Liquefied gas carrier cargo handling operations are critical to ship safety. In order to improve the quality and efficiency of cargo handling of liquefied gas carriers, the loading and unloading operation of the liquefied gas carrier was studied and a set of LPG remote cargo operation simulator with automatic bargaining function was designed. Introducing the components of the simulator: the console unit and the simulated cargo tank unit in brief, the design ideas and specific functions of the automatic barge and remote control of the core part of the system are introduced in detail. The simulator feasibility verification is carried out by comparing the error between the actual loading and unloading operation with the system simulation loading and unloading operation. The simulation training functions verification is carried out by testing people who use the simulator for training. The final results show that the error is within the acceptable range, and people who use the simulator for training can pass an authoritative comprehensive exam. It is shown that that the system can simulate the important operations in the cargo handling process and has an excellent training effect.

Since the political and legal systems are different between mainland China and Taiwan, conflict of laws issues arose in both public and private air transport laws after the launch of direct routes. Three models can be used as solutions to these issues: uniform substantive law, conflict of laws, and agreements by private institutions. The uniform substantive law model is ideal but not feasible; the conflict of laws model is possible but not realistic. The agreements by private institutions model respects private autonomy, which seems to be a supplementary yet feasible option with fragmented and conservative characteristics. Based on the characteristics of each model, the ideal way to solve this issue is to prioritise the model of agreements by carriers at this early stage and, finally, to consider uniform conflict of laws rules or substantive law when the opportunity is mature or the ultimate reunification is realised.

Boron-doped amorphous carbon (BDAC) thin films with a regular oxygen reduction reaction (ORR) catalytic activity were synthesized in a hot filament chemical vapor deposition device using a mixture of CH4 and H2 as a gas source and B2O3 as a boron source and then oxidized in air at 380–470 °C for 15–75 min. Scanning electron microscope, transmission electron microscope, Raman spectroscopy, X-ray photoelectron spectroscopy, and electrochemical tests were used to characterize the physical and electrochemical properties of the BDAC catalysts. It was concluded that the BDAC catalyst oxidized at 450 °C for 45 min showed the best ORR catalytic activity in alkaline medium. The oxygen reduction potential and the transfer electron number n, respectively, are − 0.286 V versus Ag/AgCl and 3.24 from the rotating disk electrode experiments. The treated carbon film has better methanol resistance and stability than the commercial Pt/C catalyst.

The widespread use of automobiles has greatly increased energy demand and exhaust gas pollution. In order to save energy, reduce emissions and protect the environment, making lightweights automobiles is an effective measure. In this paper, carbon fiber composites and automobile B-pillars are briefly introduced, and then the mechanical properties and impact resistance of the DC590 steel B-pillars and carbon fiber composites B-pillars are simulated by the ABAQUS finite element software. The results show that the quality of compound B-pillars is reduced by 50.76 % under the same dimensions, and the mechanical property of unit mass is significantly better than that of metal B-pillars. In the course of a collision, the kinetic energy of the two B-pillars is converted into internal energy, but the total energy remains the same; the converted internal energy of the composite B-pillars is greater, the deformation is smaller and the maximum intrusion and intrusion speed is also smaller, indicating that the anti-collision performance of the composite B-pillars is excellent. In summary, the carbon fiber composites can not only reduce the quality of the B-pillars, but also improve their anti-collision performance..

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.

｢딸을 위한 기도｣는 문학사에서 딸에 관한 시로 가장 유명한 시들 중의 하나이다. 그러나 딸이 이 시의 유일한 주제인가? 본 논문은 예이츠 자신의 자기투영의 관점에서 이 시의 이면에 깔린 부차적 텍스트를 다시 읽어내는데, 이 시에서, 딸의 미래에 대한 아버지라는 표면적 맥락에서의 기법을 사용하지만, 예이츠 자신의 과거, 현재와 미래, 자신의 나이 들어가는데 대한 걱정, 그리고 초월과 지혜의 추구 등에 대한 이 시의 부차적 텍스트가 발견되는데 그것들을 짚음으로써 그 질문에 답하려 한다.