Unraveling the effect of salt chemistry on long-durability high-phosphorus-concentration anode for potassium ion batteries

Phosphorus-based anode materials are of considerable interest for grid-scale energy storage systems due to their high theoretical capacity. Nevertheless, the low electrical conductivity of P, large volume changes during cycling, and highly-reactive phosphide surface are hindering their potential applications. Herein, outstanding long-term cycling stability with high retained potassium storage capacity (213.7 mA h g−1over 2000 cycles) was achieved via the introduction of an alternative potassium bis(fluorosulfonyl)imide (KFSI) salt and by using a layered compound (GeP5) with a high phosphorus concentration as anode material. Fourier transform infrared spectroscopic mapping results suggest that KFSI salt helps to form an uniform solid electrolyte interphase (SEI) layer and reduces the side reactions at the electrode/electrolyte interface, thus enhancing the cycling performance. In-operando synchrotron X-ray diffraction analysis has revealed the synergistic reaction mechanisms of the K-P and K-Ge reactions. These findings indicate the enormous potential of phosphorus-based anodes for high-performance potassium ion batteries and can attract broad interest for regulating the SEI layer formation through manipulating the salt chemistry

Authoritarianism in the Living Room: Everyday Disciplines, Senses, and Morality in Taiwan’s Military Villages

With the nationalist government – Kuomintang (KMT) – retreating from mainland China in 1949, some 600,000 military personnel relocated to Taiwan. The military seized former Japanese colonial properties and built its own settlements, establishing temporary military dependents’ villages called juancun (眷村). When the prospect of counter-attacking the mainland vanished, the KMT had to face the reality of settling permanently in Taiwan. How, then, did the KMT’s authoritarian power enter the everyday lives of its own support group? In this article I will focus on the coercive elements of KMT authoritarianism, which permeated these military villages in Taiwan. I will look at the coercive mechanisms through the analytical lens of Foucauldian discipline. I argue that disciplinary techniques such as surveillance, disciplining of the body and the senses, as well as the creation of morality regimes played an important role in the cooptation of village residents into KMT authoritarianism by normalising and naturalising it

Altered Striatocerebellar Metabolism and Systemic Inflammation in Parkinson’s Disease

Parkinson’s disease (PD) is the most second common neurodegenerative movement disorder. Neuroinflammation due to systemic inflammation and elevated oxidative stress is considered a major factor promoting the pathogenesis of PD, but the relationship of structural brain imaging parameters to clinical inflammatory markers has not been well studied. Our aim was to evaluate the association of magnetic resonance spectroscopy (MRS) measures with inflammatory markers. Blood samples were collected from 33 patients with newly diagnosed PD and 30 healthy volunteers. MRS data including levels of N-acetylaspartate (NAA), creatine (Cre), and choline (Cho) were measured in the bilateral basal ganglia and cerebellum. Inflammatory markers included plasma nuclear DNA, plasma mitochondrial DNA, and apoptotic leukocyte levels. The Cho/Cre ratio in the dominant basal ganglion, the dominant basal ganglia to cerebellum ratios of two MRS parameters NAA/Cre and Cho/Cre, and levels of nuclear DNA, mitochondrial DNA, and apoptotic leukocytes were significantly different between PD patients and normal healthy volunteers. Significant positive correlations were noted between MRS measures and inflammatory marker levels. In conclusion, patients with PD seem to have abnormal levels of inflammatory markers in the peripheral circulation and deficits in MRS measures in the dominant basal ganglion and cerebellum

Managing Prosecutorial Discretion Through Victim Participation in Prosecutions – a Comparative Study of the United States, Japan and Taiwan

Prosecutorial discretion is emerging as an important criminal justice reform issue in the United States. Several high-profile non-indictment decisions sparked mass protests and severely damaged the reputation of the nation’s criminal justice system. Although police officers are often implicated in fatal shooting of civilians while in the investigation, they are almost never charged and convicted. Under the current rules, two mechanisms are used to limit and monitor exercises of prosecutorial discretion in the United States - the grand jury process and preliminary hearings. However, these tools are limited. The dissertation proposes a prosecutorial supervision system by reviewing prosecutorial oversight systems in one common law and two civil law jurisdictions. Notably, the dissertation reviews public prosecution system in the United States with public prosecution systems in Taiwan and Japan. For example, Taiwan has a unique prosecutorial supervision mechanism. It empowers individuals to proceed with private prosecutions and also allows relevant parties to seek judicial review of non-prosecution decisions. Japan created Committees composed of citizens who are randomly selected by local government offices. Committees review non-prosecution decisions and order investigations. These and other review mechanisms are considered throughout this dissertation. The experiences of these two foreign jurisdictions with prosecutorial supervision are used in developing a prosecutorial supervision framework for the United States. This study of foreign jurisdictions is supplemented with a review of literature on prosecutorial discretion. The study references several academic works on victim participation in prosecutions to highlight the power of private prosecutions in supervising public prosecutors

Study on Surface Modification of Carbon Anode for Lithium-ion Batteries

本論文利用不同之表面改質技術對碳基負極材料進行處理，進而達到降低首次充放電不可逆電容量、提高循環壽命、改善快速充放電容量下降，以及提升電容量等目標。 首先，無定型碳材料具有極佳的循環壽命穩定性，然而其在首次充放電之不可逆電容量較石墨負極高很多，且電容量也較石墨低，因此本研究使用表面改質的方式對無定型碳材料首次充放電之不可逆電容量較石墨負極高與電容量也較石墨低的問題加以改善。使用不同高分子對無定型碳材料進行表面改質，由結果顯示無定型碳材料之首次不可逆值會受到比表面積之影響。同時，使用不同之瀝青包覆製程，可再次映證表面包覆層之覆蓋均勻度，對無定型碳之表面改質與首次充放電不可逆值有明顯的影響。研究中顯示出使用適量之高分子，對無定型碳材料進行表面包覆，不僅能使其不可逆值降低到20%以內，同時仍能維持材料本身極佳循環壽命之特性。最後，本研究在進行表面包覆時，添加少量之高容量矽奈米顆粒，期望能對無定型碳材料較低之電容量做進一步之改善。結果顯示所添加之矽奈米顆粒能夠均勻的分散在無定型碳材料表面，同時，此材料在1C的速率下進行循環壽命測試，於70圈後仍然有約75% 之可逆電容量保存率。 本研究同時也利用微波輔助，配合液態含矽前驅物，成功合成出具高速充放電穩定性之矽氧化物/石墨複合材料。傳統矽(矽氧化物)/碳複合材料，常使化學氣相沉積法，並配合具毒性之氣態含矽前驅物(矽烷或四氯化矽)製備。此一製程不僅危險、製程時間長且耗能﹔相較於傳統製程，微波製程具有操作時間短、液態前驅物安全、以及具選擇性等優點。在此部分，分別使用了奈米碳管、石墨片與石墨球進行包覆，由掃描式電子顯微鏡可以觀察到，由於微波加熱具有選擇性，碳及石墨基材能在短時間內被加熱到極高的溫度，並使得其周圍之液體裂解，並沉積在基材表面，形成一包覆均勻且完整之矽氧化物鍍膜層。由於此鍍膜層非熱的良導體也非微波的受體，因此鍍膜層達到一定厚度之後便不會再繼續增厚(通常所形成的鍍膜層厚度僅約幾奈米)。所得之矽氧化物/石墨複合材料進行電性測試，發現不僅在電容量上有所提升，改變放電速率時表現出極佳的穩定性，在循環壽命上也有傑出的表現，在快速充放電的條件下100圈後庫倫效率可達99.9%以上，經500次高速充放電後，仍然保有95%左右之可逆電容量的保存率。 本研究使用不同的表面改質技術，皆能夠有效的提升碳基負極材料之可逆電容量，並表現出不錯的循環壽命，同時，本研究所採用之改質技術較傳統製程簡單、安全與快速，提供日後鋰離子電池負極材料材料合成與設計新的概念。In this work, the reversible capacity, cycle life stability and rate performance can be improved by using different surface modification process. As we know, disordered carbon reveal good cycle life stability. However, despite of the favorable features, the large initial irreversible capacity and low specific capacity still are big problems and needed to be solved. Surface modification method was used to solve the weak points. The results showed that the first-cycle irreversible capacity of the disordered carbon anode and its specific surface area has a strong positive correlation. And the result was also proved by using different kinds of pitch coating process. From electrochemical test, the initial irreversibiluty can be lower than 20% by using polymer coating and the electrodes still remain good cycle stability. Small amount of Si nanoparticles was used for further improvement of the charge capacity. The Si nanoparticles can be well distribute on the disordered carbon surface by combining polymer and pitch coating. The charge capacity retention is around 75% when cycle at 1C rate after 70 cycles. Secondly, a Si oxide-coated graphite composite anode for Li-ion batteries (LIBs) was synthesized using a microwave-assisted coating method. In this synthesis, a solution comprising liquid polysiloxanes is used as the Si-containing precursor. For conventional synthesis process, people usually use chemical vapor deposition and toxic Si-containing vapor precursors, such as SinHm or SiHxCly. On the contrary, microwave-assisted coating method is safe, saving energy, and selective when doing the process. Here, carbon nano tube, graphite flake and graphite sphere were used as the microwave absorbent. Heating the graphite or carbon with microwave induces the deposition of a Si-containing conformal layer on the particle surfaces. Because the deposited layer is not microwave absorbent, it is also not good heat conductor. When the coating grew to certain thickness the reaction will stop (the thickness of the coating is around nano-scale). The resulting sample was subsequently calcined to produce SiOx/graphite composite. When tested as a LIB anode, the resulting composites exhibited an improvement in reversible specific capacity, good rate performance and excellent cyclability. When cycle at high C rate, all the composite electrodes showed the average coulombic efficiency higher than 99.9% after 100 cycles and the charge capacity retention were around 95% after 500 cycles. In this work, several polymer were chose to do surface modification. The reversible capacity, cycle life stability and rate performance of carbon anode can be improved by using different surface modification process. The results suggest new strategies for both designing and synthesizing high-performance anode materials for LIB applications

A Lightweight Continuous Authentication Protocol for the Internet of Things

Modern societies are moving toward an information-oriented environment. To gather and utilize information around people’s modern life, tiny devices with all kinds of sensing devices and various sizes of gateways need to be deployed and connected with each other through the Internet or proxy-based wireless sensor networks (WSNs). Within this kind of Internet of Things (IoT) environment, how to authenticate each other between two communicating devices is a fundamental security issue. As a lot of IoT devices are powered by batteries and they need to transmit sensed data periodically, it is necessary for IoT devices to adopt a lightweight authentication protocol to reduce their energy consumption when a device wants to authenticate and transmit data to its targeted peer. In this paper, a lightweight continuous authentication protocol for sensing devices and gateway devices in general IoT environments is introduced. The concept of valid authentication time period is proposed to enhance robustness of authentication between IoT devices. To construct the proposed lightweight continuous authentication protocol, token technique and dynamic features of IoT devices are adopted in order to reach the design goals: the reduction of time consumption for consecutive authentications and energy saving for authenticating devices through by reducing the computation complexity during session establishment of continuous authentication. Security analysis is conducted to evaluate security strength of the proposed protocol. In addition, performance analysis has shown the proposed protocol is a strong competitor among existing protocols for device-to-device authentication in IoT environments

Unraveling the effect of salt chemistry on long-durability high-phosphorus-concentration anode for potassium ion batteries

Phosphorus-based anode materials are of considerable interest for grid-scale energy storage systems due to their high theoretical capacity. Nevertheless, the low electrical conductivity of P, large volume changes during cycling, and highly-reactive phosphide surface are hindering their potential applications. Herein, outstanding long-term cycling stability with high retained potassium storage capacity (213.7 mA h g−1over 2000 cycles) was achieved via the introduction of an alternative potassium bis(fluorosulfonyl)imide (KFSI) salt and by using a layered compound (GeP5) with a high phosphorus concentration as anode material. Fourier transform infrared spectroscopic mapping results suggest that KFSI salt helps to form an uniform solid electrolyte interphase (SEI) layer and reduces the side reactions at the electrode/electrolyte interface, thus enhancing the cycling performance. In-operando synchrotron X-ray diffraction analysis has revealed the synergistic reaction mechanisms of the K-P and K-Ge reactions. These findings indicate the enormous potential of phosphorus-based anodes for high-performance potassium ion batteries and can attract broad interest for regulating the SEI layer formation through manipulating the salt chemistry