Synthesis of a magnetic π-extended carbon nanosolenoid with Riemann surfaces

Riemann surfaces are deformed versions of the complex plane in mathematics. Locally they look like patches of the complex plane, but globally, the topology may deviate from a plane. Nanostructured graphitic carbon materials resembling a Riemann surface with helicoid topology are predicted to have interesting electronic and photonic properties. However, fabrication of such processable and large π-extended nanographene systems has remained a major challenge. Here, we report a bottom-up synthesis of a metal-free carbon nanosolenoid (CNS) material with a low optical bandgap of 1.97 eV. The synthesis procedure is rapid and possible on the gram scale. The helical molecular structure of CNS can be observed by direct low-dose high-resolution imaging, using integrated differential phase contrast scanning transmission electron microscopy. Magnetic susceptibility measurements show paramagnetism with a high spin density for CNS. Such a π-conjugated CNS allows for the detailed study of its physical properties and may form the base of the development of electronic and spintronic devices containing CNS species

Vertical Integration in the Maritime Industry: Container Shipping Line Investment in Ports and Terminals

The container liner shipping industry is experiencing a very challenging phase. The market has not ever recovered from the Financial Crisis of 2008 and further stuck by the new fuel requirements, trade friction and pandemic in 2020. Shipping lines, confronting the market downturn, are expanding their service coverage via vertical integration to get involved in terminal operation industry. Motivated by these empirical insights and the lack of conclusive evidence in the literature, this thesis is targeted to investigate the impacts of vertical integration in the context of container liner shipping industry between shipping lines and terminal operators. Based on an extensive literature review, it is found that vertical integration usually is beneficial to the integrated company. At the same time, its impacts on the end customers and the whole market is ambiguous. To safeguard the interests of different stakeholders, it is necessary to discuss how vertical integration would influence on the social welfare and competition, considering the features of container liner shipping industry. The thesis' contribution to this research field is threefold. Firstly, the thesis develops an analytical economic model that incorporates port authority, terminal operator and shipping lines. The analysis suggests that vertical integration between the terminal operator and a shipping line leads to a higher port capacity, port charge, market output, consumer surplus and social welfare. It could also alleviate the congestion in ports. Secondly, the thesis uses collected data to compare vertically integrated ports with non-integrated ports. With the world top 100 ports data, a series of statistical tests are conducted to prove that vertical integration indeed has positive correlations with port throughput and size. Then, it is found that vertically integrated ports' efficiency is inferior to not integrated ports. The comparative bigger capacity and lower efficiency could be attributed to the aggravated overcapacity problem introduced by the lumpy investment in the port industry. Thirdly, the thesis investigates how would vertical integration impacts business decisions from the perspective of shipping lines. By collecting shipping lines' routes serving East Asia, it is confirmed that shipping lines prefer to call at affiliated ports that are directly integrated by themselves or indirectly via their alliance partners. In addition to the impacts of vertical integration, shipping lines' spatial entry pattern in the East Asia market is studied

Rail Quality Based Index

The aim of this thesis is to establish an integrated rail quality based index to evaluate different freight wagons’ performance. All materials are collected through literature reviews and interviews. The Rail Quality Based Index (RQBI) is established in the form of cost that can represent the main quality aspects associated with freight wagons self-characteristics. The index construction includes four main components, i.e. infrastructure, energy, maintenance and noise. Each component’s cost can be calculated by applying different methods from previous studies. By comparing index value with benchmark, the RQBI can help different parties in rail freight industry to evaluate and compare their freight wagons quality performance. This research concludes costs differentiated by wagons’ characteristics and tries to represent them in an integrated index’s form. Though, due to data deficiency, validation of the index and establishment of relevant benchmarks are not fully discussed in this research, it helps to further understand quality evaluation of freight wagons and points out a new perspective of future relevant researches

Co-Modality for Sydney’s Ferries

Logistics issues arising from the last mile delivery of goods in an urban environment are plentiful. Co-modality, whereby the movement of freight and passengers are integrated on the same public transport mode, can mitigate road congestion and promote sustainable transport. This working paper investigates the merits of using co-modality for the ‘intermediate mile’ with Sydney’s ferries in Australia. A global review of field trials found that a high level of stakeholder interaction and a robust data management system are necessary to ensure the success of the endeavour. A review of the transit assignment literature led to the selection of the frequency-based transit assignment model to locate spare capacity in the ferry network before the pandemic. Additionally, there was an evaluation of every ferry station’s suitability for handling cargo with proposals for storage areas within each ferry station. An assessment of a range of Unit Load Devices (ULDs) in which goods are carried led to the selection of the ‘meter cube’ container as the most viable for Sydney’s ferries. Tracking and tracing requirements were reviewed. Four business models are developed for different delivery processes and types of cargo – pickup and delivery of full meter cube containers, parcels transported in meter cube containers, or perishable goods transported in refrigerated meter cube containers. The repositioning of empty meter cube containers is not considered in detail. Potential limitations, risks and next steps for the successful implementation of co-modality for Sydney’s ferries are detailed

Establishing A Intermodal Freight Corridor

This research paper is inspired by some our classmate’s work and also the overall trade relation between China and Taiwan. As China’s relevant policy, many Taiwanese companies are now investing in the southwest inland cities of China. Together with the fact that China is now the biggest trading partner of Taiwan together with Taiwan’s industrial layout, it is by interest to investigate the feasibility of building a new transport service from Taiwan directly to southwest China. We focus on introducing an intermodal option to link Taipei, the capital of Taiwan, and Chengdu, the largest city in Sichuan province. Our transshipment port in this project is Xiamen, which is one of the closest ports to Taiwan in China. The main target of this report is the electronics industry and its time sensitive goods associated with these products. Certain market forces are aligned and we believe there is a potential for a profitable trade corridor to be established. Detailed studies on cost analysis, system setup choice, market analysis and overall implementations are drawn to justify our idea and choice of this trade route.GS Research paper/GM0516 Intermodal Freight Transpor

Vertical Integration and its Implications to Port Expansion

Over the years many shipping lines have established terminal operation companies, with some set up as independent firms. However, port authorities and local governments have not always welcomed external investment and control with open arms. The economic implications and each stakeholder’s best strategies remain unclear. This study develops an analytical model in order to study the effects of vertical integration, with a focus on shipping lines’ investment in ports’ capacity. Modelling results suggest that vertical integration between terminal operator and a shipping line leads to higher port capacity, port charge, market output and consumer surplus. It also reduces delay costs. All these results suggest that vertical integration can be an important source of synergy for the maritime industry. Although vertical integration increases the participating carrier’s output at the expenses of non-integrating rival shipping firms, the overall social welfare is still improved, which is indicated through the numerical analysis. Therefore, port authorities and government regulators should carefully review the market competition status as well as port expansion plans

A metal-free photoactive nitrogen-doped carbon nanosolenoid with broad absorption in visible region for efficient photocatalysis

Abstract Riemann surfaces inspired chemists to design and synthesize such multidimensional curved carbon architectures. It has been predicted that carbon nanosolenoid materials with Riemann surfaces have unique structures and novel physical properties. Here we report the first synthesis of a nitrogen-doped carbon nanosolenoid (N-CNS) using bottom-up approach with a well-defined structure. N-CNS was obtained by a rational Suzuki polymerization, followed by oxidative cyclodehydrogenation. The successful synthesis of N-CNS was fully characterized by GPC, FTIR, solid-state 13C NMR and Raman techniques. The intrinsic single-strand molecular structures of N-CNS helices can be clearly resolved using low-dose integrated differential phase contrast scanning transmission electron microscopy (iDPC-STEM) technique. Possessing unique structural and physical properties, this long π-extended polymer N-CNS can provide new insight towards bottom-up syntheses of curved nanoribbons and potential applications as a metal-free photocatalyst for visible-light-driven H2 evolution and highly efficient photocatalyst for photoredox organic transformations

Altered gut microbiota after traumatic splenectomy is associated with endotoxemia

Abstract Splenectomy carries a long-term risk of postoperative infection, and the chronic, low-grade inflammation associated with endotoxemia may be related to the gut microbiota. In this study, to increase our understanding of the potential cause of the high rate of infection in postsplenectomy patients, we evaluated the differences in the gut microbiota and plasma lipopolysaccharide level of patients after splenectomy relative to those of healthy controls. Thirty-two patients having undergone splenectomy and 42 healthy individuals were enrolled into the splenectomy (SP) and healthy control (HC) groups, respectively. The SP group was subdivided into three subgroups according to the length of their postoperative time. Fecal samples were used for gut microbiota analysis via 16s rRNA gene sequencing, blood examinations and plasma lipopolysaccharide measurements were also taken. Significant differences were observed in gut microbiota composition with regard to the relative bacterial abundances of 2 phyla, 7 families, and 15 genera. The lipopolysaccharide level was significantly higher in the SP group than in the HC group and were negatively associated with five bacterial families with low abundance in the SP group. The degree of the microbiota alteration increased with the length of the postoperative time. The PICRUSt analysis showed that the relative abundances of lipopolysaccharide biosynthesis proteins and lipopolysaccharide biosynthesis pathways were higher in the SP group and were positively associated with the plasma lipopolysaccharide level. Significant alterations were observed in the gut microbiota of the splenectomized patients and were associated with plasma lipopolysaccharide level. Further studies are needed to verify whether such alterations after splenectomy are related to an increased risk of complications