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1 108/2 經濟系 陳智華 教授 期刊論文 發佈 消費外部性與經濟成長:兩部門模型的意涵 , [108-2] 摘要:單部門成長模型強調消費外部性影響經濟體系的途徑是就業效果,因此在勞動供給外生決定的環境下,消費外部性並不會影響總體經濟表現。不同於既存文獻,本文設計一個納入消費外部性的兩部門成長模型並指出,消費外部性影響總體經濟體系的管道除了就業效果,還包括資源重分配效果。在固定規模報酬生產技術的假設下,不需要藉助就業效果,資源重分配效果會使得資本密集商品的消費外部性與經濟成長具有正向關係,但勞動密集商品的消費外部性與經濟成長率的關係則呈現不確定的狀態。另外,我們也討論了消費稅政策並發現兩部門架構下,資本密集商品的消費稅比較可能會傷害經濟成長表現,但勞動密集商品的消費稅對於經濟成長率的影響並不確定。
2 103/2 資工系 潘孟鉉 教授 期刊論文 發佈 An Enhanced Handover Scheme for Mobile Relays in LTE-A High-Speed Rail Networks , [103-2] 摘要:Recently, the mobile relay technique has been discussed to support communication services for Long-Term Evolution Advanced (LTE-A) high-speed rail networks. In the network, there are several mobile relays in a train. User equipment (UE) devices connect to in-car mobile relays instead of outside evolved NodeBs (eNBs). Mobile relays establish backhaul links with the serving donor eNBs (DeNBs) and coordinate control and data flows for UE devices. Since the train travels in high speed, mobile relays suffer from frequent handovers between DeNBs. We observe that the defined handover procedures in LTE-A specifications may incur message overhead and lengthen handover time. In this paper, we propose an enhanced handover scheme, which contains two procedures. The first procedure is an enhanced measurement procedure, which can accelerate the measurement procedure when the mobile relay knows that the train is moving toward some neighbor DeNBs. The second procedure is a group in-network handover procedure, which can aggregate similar in network handover procedures in the core network. Performance evaluations indicate that our design can conserve both time and messages when handover.
3 103/2 化學系 王三郎 教授 期刊論文 發佈 Recent advances in exopolysaccharides from Paenibacillus spp.: Production, isolation, structure, and bioactivities , [103-2] 摘要:This review provides a comprehensive summary of the most recent developments of various aspects (i.e., production, purification, structure, and bioactivity) of the exopolysaccharides (EPSs) from Paenibacillus spp. For the production, in particular, squid pen waste was first utilized successfully to produce a high yield of inexpensive EPSs from Paenibacillus sp. TKU023 and P. macerans TKU029. In addition, this technology for EPS production is prevailing because it is more environmentally friendly. The Paenibacillus spp. EPSs reported from various references constitute a structurally diverse class of biological macromolecules with different applications in the broad fields of pharmacy, cosmetics and bioremediation. The EPS produced by P. macerans TKU029 can increase in vivo skin hydration and may be a new source of natural moisturizers with potential value in cosmetics. However, the relationships between the structures and activities of these EPSs in many studies are not well established. The contents and data in this review will serve as useful references for further investigation, production, structure and application of Paenibacillus spp. EPSs in various fields.
4 104/1 資工系 張志勇 教授 期刊論文 發佈 Design and Implementation of an IoT Access Point for Smart Home , [104-1] 摘要:Network communication and micro-electro-mechanical embedded technologies have attracted much attention in recent years. Through these technologies, the capabilities of sensing, identification, and communication can be embedded in various smart devices. These smart devices can automatically connect to the Internet and form an intelligent network called Internet of Things (IoT). However, these devices are embedded with different wireless communication interfaces such as Wi-Fi and ZigBee. This paper presents the design and implementation of an IoT access point that supports functionalities of coordination of various wireless transmission protocols. Based on the existing Wi-Fi access point, we have embedded a ZigBee module and implemented ZigBee and UPnP protocols into the designed IoT access point, which supports ZigBee communication capabilities over the Internet.
5 102/2 電機系 莊程豪 教授 期刊論文 發佈 The effect of thermal reduction on the photoluminescence and electronic structures of graphene oxides , [102-2] 摘要:Electronic structures of graphene oxide (GO) and hydro-thermally reduced graphene oxides (rGOs) processed at low temperatures (120–180°C) were studied using X-ray absorption near-edge structure (XANES), X-ray emission spectroscopy (XES) and resonant inelastic X-ray scattering (RIXS). C K-edge XANES spectra of rGOs reveal that thermal reduction restores C = C sp2 bonds and removes some of the oxygen and hydroxyl groups of GO, which initiates the evolution of carbonaceous species. The combination of C K-edge XANES and Kα XES spectra shows that the overlapping π and π* orbitals in rGOs and GO are similar to that of highly ordered pyrolytic graphite (HOPG), which has no band-gap. C Kα RIXS spectra provide evidence that thermal reduction changes the density of states (DOSs) that is generated in the π-region and/or in the gap between the π and π* levels of the GO and rGOs. Two-dimensional C Kα RIXS mapping of the heavy reduction of rGOs further confirms that the residual oxygen and/or oxygen-containing functional groups modify the π and σ features, which are dispersed by the photon excitation energy. The dispersion behavior near the K point is approximately linear and differs from the parabolic-like dispersion observed in HOPG.
6 102/2 化材系 董崇民 教授 期刊論文 發佈 Unusual mechanical properties of melt-blended poly(lactic acid) (PLA)/clay nanocomposites, , [102-2] 摘要:The commercial organic-modified clay was incorporated into a nearly amorphous PLA matrix using a melt-blending process to form PLA/clay nanocomposites. The nanocomposite containing 1 phr of clay conferred the highest exfoliation of clay among all investigated clay dosages. Especially, only this particular nanocomposite had a lower modulus and exhibited significant stress-whitening and necking behavior with a large extension, elongation at break being increased to 208%, up to 37-fold increment compared to the neat PLA. Based on SEM and TEM pictures, the highly exfoliated platelets produced a relatively large interfacial area between the clay platelet and PLA matrix, which resulted in a comprehensively plasticized interfacial region. The highly plasticized interfacial region and the well-dispersed clay platelets with high aspect ratio, particular for thin samples, enhanced the multiple shear-banding which induced the plastic deformation and substantial shear yielding behavior. It also caused a decrease in the spherulite nucleation behavior of the PLA. On the contrary, when the clay was added at higher amounts, it existed mostly in the form of intercalated structure which acted as rigid filler, raising the modulus and causing an early failure in the tensile test. Both Halpin–Tsai and Mori–Tanaka equations were used to predict the modulus of the nanocomposites at higher clay contents where the Mori–Tanaka equation gave a better prediction.
7 104/1 資工系 潘孟鉉 教授 期刊論文 發佈 Downlink Traffic Scheduling for LTE-A Small Cell Networks With Dual Connectivity Enhancement , [104-1] 摘要:Small cells are a promising solution to increase the network capacity and to offload network traffic for LTE-A networks. In an LTE-A small cell network, there is one macro eNB (MeNB) and several slave eNBs (SeNBs). Recently, the dual connectivity technology is proposed for enhancing LTE-A small cell networks. For a user equipment (UE) that has dual connectivity, the MeNB can split the UE's downlink traffic and enable this UE to receive its downlink data from the MeNB and an SeNB simultaneously. In this work, we propose a downlink traffic scheduling (DTS) scheme for the MeNB to arrange the data rate of downlink traffic splitting to SeNBs for UEs that have dual connectivity. Simulation results indicate that the proposed scheme can effectively increase the network throughput for LTE-A small cell networks with dual connectivity enhancement.
8 104/2 管科系 李培齊 教授 期刊論文 發佈 Innovation-oriented supply chain integration for combined competitiveness and firm performance , [104-2] 摘要:This study examined the combined impact of an innovation orientation, supply chain integration (customer integration, supplier integration, and internal integration), and combinative competitive capabilities on firm performance. A total of 480 questionnaires were collected from companies in the Taiwanese electronics industry. Structural equation modeling (SEM) was employed to analyze the collected data. An innovation orientation was shown to positively affect supply chain integration, combinative competitive capabilities, and firm performance. Supply chain integration (in particular, supplier integration and internal integration) had a mediation effect on innovation orientation and business performance, whereas combinative competitive capabilities had a mediation effect on supply chain integration and firm performance. The results provide empirical support for the notion that an innovation orientation affects supply chain integration and firm performance. Drawing from previous studies on resource dependence theory, this study indicates how innovation orientation assists firms in integrating their supply chains and realizing the potential of the supply chain management mechanism. This paper presents the interrelatedness of innovation orientation, supply chain integration, combinative competitive capabilities, and firm performance.
9 101/2 資創系 黃煌文 副教授 期刊論文 發佈 Influence of blood vessel on the thermal lesion formation during radiofrequency ablation for liver tumors , [101-2] 摘要:Purpose: The major obstacles of radiofrequency ablation (RFA) heat treatments are nonuniform heating in the thermal lesion and heat sinks caused by large blood vessels during treatments which could lead to high tumor recurrence in patients. The objective of this study is to help comprehend RFA heat treatment through thermal lesion formation using computer simulation, and thus to provide helpful assistance in planning RFA. Methods: RFA heat treatment is a popular “minimally invasive” treatment method for both primary and metastatic liver tumors, and the heat treatment is studied by numerical calculation. A finite difference model is used to solve all partial differential equations for a simple three‐dimensional cubic geometry model. Maximum tissue temperature is used as a critical index for reaching thermal lesion during RFA. Cylindrical RF cool‐tip electrode is internally cooled at constant water temperature. RFA thermal lesion is studied at various impacts by single and countercurrent blood vessel(s) traversing the thermal lesion. Several factors are considered, such as location, diameter, and orientation of the blood vessel(s) to the electrode. Results: Results show the thermal lesion size decreases as the lesion blood perfusion rate increases. And, single large blood vessel which is orthogonal to RF electrode will cause less undercooled volume in the thermal lesion than one which is parallel to RF electrode. Furthermore, convective energy may easily damage parallel vessel and its surrounding normal tissues during RFA. Small blood vessels (or larger vessels with slow blood flow rate) during RFA could form “tail‐like” thermal lesion formation, which could damage vessel downstream spots. Conclusions: Studies suggested that incomplete RF tumor ablation still exists within 1 cm distance between large blood vessel and RF electrode in a liver. This could have significant impact on local tumor recurrence rates. Second, if thermally significant vessel existed inevitably within the lesion, avoiding the RF cool‐tip electrode placement next to the parallel large blood vessel would have a better heat treatment during RF heating. Additionally, reduced blood flow rate could help reduce significant cooling by large blood vessel.
10 101/2 資創系 惠 霖 副教授 期刊論文 發佈 Apply HIP to Handover Procedures in Hybrid Access Mode LTE Femtocells , [101-2] 摘要:Femtocell networks that use Home evolved NodeB (HeNB) and existing networks for backhaul connectivity can fulfill the upcoming demand for high data rates in wireless communication systems as well as extend the coverage area. In this paper we seem handover between femtocell and macrocell as a heterogeneous handover and apply the Host Identity Protocol (HIP) with Media Independent Handover (MIH) to achieve handover execution. It considers handover parameters for, including interference, velocity, RSS and quality of service (QoS) level. We propose a new handover strategy based on HIP between the femtocell and the macrocell for LTE (Long Term Evolution) -based networks in hybrid access mode. This strategy can avoid unnecessary handovers and can reduce handover failure.
11 109/2 化學系 潘伯申 副教授 期刊論文 發佈 Salvage Boron Neutron Capture Therapy for Malignant Brain Tumor Patients in Compliance with Emergency and Compassionate Use: Evaluation of 34 Cases in Taiwan , [109-2] 摘要:Although boron neutron capture therapy (BNCT) is a promising treatment option for malignant brain tumors, the optimal BNCT parameters for patients with immediately life-threatening, end-stage brain tumors remain unclear. We performed BNCT on 34 patients with life-threatening, end-stage brain tumors and analyzed the relationship between survival outcomes and BNCT parameters. Before BNCT, MRI and 18F-BPA-PET analyses were conducted to identify the tumor location/distribution and the tumor-to-normal tissue uptake ratio (T/N ratio) of 18F-BPA. No severe adverse events were observed (grade ≥ 3). The objective response rate and disease control rate were 50.0% and 85.3%, respectively. The mean overall survival (OS), cancer-specific survival (CSS), and relapse-free survival (RFS) times were 7.25, 7.80, and 4.18 months, respectively. Remarkably, the mean OS, CSS, and RFS of patients who achieved a complete response were 17.66, 22.5, and 7.50 months, respectively. Kaplan–Meier analysis identified the optimal BNCT parameters and tumor characteristics of these patients, including a T/N ratio ≥ 4, tumor volume < 20 mL, mean tumor dose ≥ 25 Gy-E, MIB-1 ≤ 40, and a lower recursive partitioning analysis (RPA) class. In conclusion, for malignant brain tumor patients who have exhausted all available treatment options and who are in an immediately life-threatening condition, BNCT may be considered as a therapeutic approach to prolong survival.
12 109/2 財金系 黃健銘 助理教授 期刊論文 發佈 高管薪酬淚勵能促進智力資本自願信息披露嗎? , [109-2] 摘要:以我国高科技上市公司为样本,利用大样本的智力资本自愿信息披露指数,实证检验高管薪酬激励对智力资本自愿信息披露行为的影响,并进一步考察在不同的产品市场竞争环境中,这一影响机制的异质性特征。研究结果表明:不管以绝对薪酬还是超额薪酬度量高管薪酬激励,其与智力资本自愿信息披露间都存在显著为正的关系,即高管薪酬越高,智力资本自愿信息披露水平越高。产品市场竞争对高管薪酬与智力资本信息披露间的关系存在显著正向的调节效应,即越是处于竞争激烈的市场环境中,高管薪酬对智力资本自愿信息披露水平的提升效应越明显。较之于非国有控股
13 108/2 統計系 吳錦全 教授 期刊論文 發佈 Analysis of the estimation of process capability index of non-normal process data using the lognormal distributions , [108-2] 摘要:In recent years, process capability indices (PCIs) have been widely applied in quality control by most practitioners to assess whether the production process reaches a required level. However, the characteristic variable in many industrial production processes has non-normal distribution. This paper uses the Clements’s method to estimate four non-normal process capability indices for lognormal distribution. A simulation study is done to analyze the influence of skewness and kurtosis on the precision of estimation of process capability indices for the given distribution.
14 109/1 學動組 洪敦賓 副教授 期刊論文 發佈 運用學習社群方式探討大學生體育課滿意度及其影響因素 , [109-1] 摘要:緒論:以學習社群及體適能健康主題相關電影融入教學,幫助學生了解體適能的重要性,協助建構正確運動觀念及重視生命意義價值之課程為主,並檢視課程介入後學習動機及學習滿意度是否提升。方法:以學習社群教學研究設計,研究對象共279位大學生,選取「肥胖」、「健康生活形態」及「體適能與健康管理」等三部健康體適能主題相關影輯為主要教學媒材,設計出三個單元、10節課,融入健康體適能的教學課程,共實施十週。教學結束後,填寫「體育課影片觀賞問卷」、「ARCS學習動機理論量表」、「體育課學習滿意度量表」。結果:一、「影片鑑賞」、「學習動機」及「學習滿意度」之間均有顯著的中等程度相關性。二、「影片鑑賞」、「學習動機」對「學習滿意度」具有部分影響力,且「影片鑑賞」與「學習動機」對「教師教學」及「班級氣氛」具有重要的影響力。「影片鑑賞」與「學習動機」對「場地器材」、「安全衛生」及「學校行政」則較不具重要的影響力。結論:學習社群教學模式有助學生學習、強化學習動機及提升學習滿意度。
15 109/1 化學系 潘伯申 副教授 期刊論文 發佈 Catalyst-free synthesis of borodepsipeptides using isocyano arylboronate under aqueous condition , [109-1] 摘要:Herein, the synthesis of borodepsipeptides utilizing boron-containing isocyanides is described. The target compounds were synthesized via Passerini three-component reaction (P-3CR), in which H2O was utilized as the solvent. Further, unlike conventional P-3CR, where Lewis acid catalysts are often required, the reported method requires no catalyst and proceeds in room temperature. A variety of aldehydes and acids were used as the building blocks to generate the desired products.
16 108/1 化學系 潘伯申 副教授 期刊論文 發佈 Synthesis of boron-containing tetrazoles under neutral microwave-assisted conditions , [108-1] 摘要:In this report, the mild synthetic strategies for the synthesis of two series of boron-containing tetrazoles were included. For the first series, a boron-containing isocyanide reacted with TMS-N3 to afford the desire products. The reaction took place at 60 °C in TFE for 30 min under microwave irradiation. For the second series, the Ugi four-component reaction (Ugi-4CR) was deployed to synthesize the desire products. The reaction took place simply in MeOH at ambient temperature for 2 h. The synthetic strategies included could provide access to ranges of boron-containing tetrazole libraries, which might possess unique biological properties.
17 107/1 化學系 潘伯申 副教授 期刊論文 發佈 Synthesis of multiple boron-containing analogs via Ugi-4CR , [107-1] 摘要:One of the most significant challenges in boron neutron capture therapy (BNCT) is to have an ideal boron delivery agent which can deliver sufficient numbers of boron atoms to designated tumor cells. In this work, mild synthetic conditions for synthesis of dipeptidyl multiple boron-containing analogs under microwave-assisted condition were investigated. The results showed that the reaction generally took place at 50 °C, but higher reaction temperature was required when a fluorinated building block was used. The resulting peptidyl skeletons generated by Ugi four-component reaction resemble basic cell metabolites and could potentially be used as alternative replacements for current boron carrier agents in BNCT.
18 109/1 化學系 蔡旻燁 助理教授 期刊論文 發佈 Modeling Protein Aggregation Kinetics: The Method of Second Stochasticization , [109-1] 摘要:The nucleation of protein aggregates and their growth are important in determining the structure of the cell’s membraneless organelles as well as the pathogenesis of many diseases. The large number of molecular types of such aggregates along with the intrinsically stochastic nature of aggregation challenges our theoretical and computational abilities. Kinetic Monte Carlo simulation using the Gillespie algorithm is a powerful tool for modeling stochastic kinetics, but it is computationally demanding when a large number of diverse species is involved. To explore the mechanisms and statistics of aggregation more efficiently, we introduce a new approach to model stochastic aggregation kinetics which introduces noise into already statistically averaged equations obtained using mathematical moment closure schemes. Stochastic moment equations summarize succinctly the dynamics of the large diversity of species with different molecularity involved in aggregation but still take into account the stochastic fluctuations that accompany not only primary and secondary nucleation but also aggregate elongation, dissociation, and fragmentation. This method of “second stochasticization” works well where the fluctuations are modest in magnitude as is often encountered in vivo where the number of protein copies in some computations can be in the hundreds to thousands. Simulations using second stochasticization reveal a scaling law that correlates the size of the fluctuations in aggregate size and number with the total number of monomers. This scaling law is confirmed using experimental data. We believe second stochasticization schemes will prove valuable for bridging the gap between in vivo cell biology and detailed modeling.
19 109/2 化學系 王三郎 教授 期刊論文 發佈 Conversion of pectin-containing by-products to pectinases by Bacillus amyloliquefaciens and its applications on hydrolyzing banana peels for prebiotics production , [109-2] 摘要:The utilization of pectin-containing by-products may be useful in a variety of fields. This study aims to establish the processing of pectin-containing by-products to produce pectinases using Bacillus amyloliquefaciens TKU050 strain. In this study, several kinds of agricultural pectin-containing by-products from banana (banana peel), rice (rice bran), orange (orange peel), coffee (spent coffee grounds), and wheat (wheat bran) were utilized to provide carbon sources for the production of a pectinase by B. amyloliquefaciens TKU050. B. amyloliquefaciens TKU050 expressed the highest pectinase productivity (0.76 U/mL) on 0.5% wheat bran-containing medium at 37 °C for four days. A 58 kDa pectinase was purified from the four-day cultured medium fermented under optimized culture conditions with 7.24% of a recovery ratio and 0.51 U/mg of specific activity, respectively. The optimum temperature, optimum pH, thermal stability, and pH stability of the TKU050 pectinase were 50 °C, pH 6, <50 °C, and pH 6–9, respectively. The TKU050 pectinase was inhibited by sodium dodecyl sulfate and Cu2+. The reducing sugar obtained by hydrolyzing banana peel with TKU050 pectinase showed the growth-enhancing effect on the growth of four tested lactic acid
20 104/1 數學系 鄭 堯 助理教授 期刊論文 發佈 Non-vanishing of central L-values of canonical CM elliptic curves with quadratic twists , [104-1] 摘要:The aim of this paper is to extend results of Rorlich, Villegas and Yang about the non-vanishing of central L-values of canonical characters of imaginary quadratic fields over the rationals. One of the new ingredients in our paper is the local computations at the place “2”. Therefore, we extend their non-vanishing results to include imaginary quadratic fields of even discriminant. As a consequence, we show that the rank of the Mordell–Weil groups of certain canonical CM elliptic curves are zero.
21 108/2 土木系 李英豪 教授 期刊論文 發佈 李院健康好宅設計理論與實踐 , [108-2] 摘要:健康好宅设计包含物理性、生物性、心理性、社会性及公平性等环境影响因素,通过李院健康好宅案例验证环境影响因素的设计技术要点,供相关学者与使用者参考。其设计技术要点经证实可行,如室内分区设计有益健康舒适并能减少室内病毒传染,热浮力通风塔设计散热有效且能美化都市景观,现代人越来越重视心理性影响因素,平面经济高效的住宅是未来趋势。
22 109/2 電機系 莊程豪 教授 期刊論文 發佈 透由原位電化學技術來探討硫酸銅溶液中電鍍和電溶解效應 , [109-2] 摘要:本工作使用軟X光吸收光譜、電化學石英微天平、和熱脫附質譜儀技術,觀測如何從pH 4.8硫酸銅溶液中銅離子電鍍生長和溶解的機制。發現電鍍銅過程可產生過氫氧根,穩定住Cu^+氧化態和避免金屬銅(Cu^0)產生。氧化亞銅表面生成羥基氧化物(oxy-hydroxide)形成介面水合氧化物(Cu_2O_(aq)),在後半段中陽極掃描中產生穩定氧化銅(CuO)結構和其Cu^(2+)氧化態,但在更高陽極電壓下,仍出現化學降解和表面溶解現象。臨場電位循環實驗中發現,相對於電鍍過程所需電子數目,溶解過程只收回更少電子數目,原因出自於水催化現象和反應中途所產生質子產物的伴隨效應。
23 109/2 數學系 郭忠勝 教授 期刊論文 發佈 Persistence of preys in a diffusive three species predator-prey system with a pair of strong-weak competing preys , [109-2] 摘要:We investigate the traveling wave solutions of a three-species system involving a single predator and a pair of strong-weak competing preys. Our results show how the predation may affect this dynamics. More precisely, we describe several situations where the environment is initially inhabited by the predator and by either one of the two preys. When the weak competing prey is an aboriginal species, we show that there exist traveling waves where the strong prey invades the environment and either replaces its weak counterpart, or more surprisingly the three species eventually co-exist. Furthermore, depending on the parameters, we can also construct traveling waves where the weaker prey actually invades the environment initially inhabited by its strong competitor and the predator. In all those situations, we find the infimum of the set of admissible wave speeds; these results are sharp at least when the three species diffusive at the same speed.
24 109/2 數學系 郭忠勝 教授 期刊論文 發佈 Recent developments on a singular predator-prey model , [109-2] 摘要:This work is concerned with the dynamical behaviors of a singular predator-prey model. We first review some well-known results obtained recently. Then we give some new results on the spreading speed of the predator, the existence vs non-existence of traveling waves connecting the predator-free state to the co-existence state, and the existence vs non-existence of spatially periodic traveling waves to this singular predator-prey system.
25 109/1 數學系 郭忠勝 教授 期刊論文 發佈 Traveling wave solutions for some three-species predator-prey systems , [109-1] 摘要:In this paper, we present some recent developments on the application of Schauder’s fixed point theorem to the existence of traveling waves for some three-species predator-prey systems. The existence of traveling waves of predator-prey systems is closely related to the invasion phenomenon of some alien species to the habitat of aboriginal species. Three different three-species predator-prey models with different invaded and invading states are presented. In this paper, we focus on the methodology of deriving the convergence of stale tail of wave profiles.
26 109/1 數學系 郭忠勝 教授 期刊論文 發佈 Asymptotic spreading speeds for a predator-prey system with two predators and one prey , [109-1] 摘要:This paper investigates the large time behaviour of a three species reaction–diffusion system, modelling the spatial invasion of two predators feeding on a single prey species. In addition to the competition for food, the two predators exhibit competitive interactions and, under some parameter condition, they can also be considered as two mutants. When mutations occur in the predator populations, the spatial spread of invasion takes place at a definite speed, identical for both mutants. When the two predators are not coupled through mutation, the spreading behaviour exhibits a more complex propagating pattern, including multiple layers with different speeds. In addition, some parameter conditions reveal situations where a nonlocal pulling phenomenon occurs and in particular where the spreading speed is not linearly determined.
27 109/1 電機系 莊程豪 教授 期刊論文 發佈 Black phosphorus composites with engineered interfaces for high-rate high-capacity lithium storage , [109-1] 摘要:High-rate lithium (Li) ion batteries that can be charged in minutes and store enough energy for a 350-mile driving range are highly desired for all-electric vehicles. A high charging rate usually leads to sacrifices in capacity and cycling stability. We report use of black phosphorus (BP) as the active anode for high-rate, high-capacity Li storage. The formation of covalent bonds with graphitic carbon restrains edge reconstruction in layered BP particles to ensure open edges for fast Li+ entry; the coating of the covalently bonded BP-graphite particles with electrolyte-swollen polyaniline yields a stable solid– electrolyte interphase and inhibits the continuous growth of poorly conducting Li fluorides and carbonates to ensure efficient Li+ transport. The resultant composite anode demonstrates an excellent combination of capacity, rate, and cycling endurance.
28 108/2 電機系 莊程豪 教授 期刊論文 發佈 CuFeO2–CeO2 nanopowder catalyst prepared by self-combustion glycine nitrate process and applied for hydrogen production from methanol steam reforming , [108-2] 摘要:Hydrogen (H2) is being considered as an alternate renewable energy carrier due to the energy crisis, climate change and global warming. In the chemical industry, hydrogen production is mainly accomplished by the steam reforming of natural gas. In the present study, CuFeO2eCeO2 nanopowder catalyst with a heterogeneous delafossite structure was prepared by the self-combustion glycine nitrate process and used for steam reforming of methanol (SRM). The precursor solution was fabricated from CueFeeCe metal-nitrate mixed with glycine and an aqueous solution. The prepared CuFeO2eCeO2 nanopowder catalyst was studied by different physical and chemical characterization techniques. The prepared CuFeO2eCeO2 nanopowder catalyst was immensely porous with a coral-like structure. The BET surface area measurement revealed that the specific surface area of as-combusted CuFeO2eCeO2 nanopowder varied from 5.6248 m2/g to 19.5441 m2/g. In addition, the production rate of CuFeO2eCeO2 was improved by adding CeO2 and adjusting the feeding rate of the methanol. The highest H2 generation rate of the CuFeO2eCeO2 catalyst was 2582.25 (mL STP min1 g-cat1) at a flow rate of 30 sccm at 400 C. Hence, the high specific surface area of the 70CuFeO2e30CeO2 nanopowder catalyst and the steam reforming process could have a very important industrial and economic impact.
29 110/1 電機系 莊程豪 教授 期刊論文 發佈 Molten salt assisted fabrication of Fe@FeSA-N-C oxygen electrocatalyst for high performance Zn-air battery , [110-1] 摘要:Non-noble-metal-based electrocatalysts with superior oxygen reduction reaction (ORR) activity to platinum (Pt) are highly desirable but their fabrications are challenging and thus impeding their applications in metal-air batteries and fuel cells. Here, we report a facile molten salt assisted two-step pyrolysis strategy to construct carbon nanosheets matrix with uniformly dispersed Fe3N/Fe nanoparticles and abundant nitrogen-coordinated Fe single atom moieties (Fe@FeSA-N-C). Thermal exfoliation and etching effect of molten salt contribute to the formation of carbon nanosheets with high porosity, large surface area and abundant uniformly immobilized active sites. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) image, X-ray absorption fine spectroscopy, and X-ray photoelectron spectroscopy indicate the generation of Fe (mainly Fe3N/Fe) and FeSA-N-C moieties, which account for the catalytic activity for ORR. Further study on modulating the crystal structure and composition of Fe3N/Fe nanoparticles reveals that proper chemical environment of Fe in Fe3N/Fe notably optimizes the ORR activity. Consequently, the presence of abundant FeSA-N-C moieties, and potential synergies of Fe3N/Fe nanoparticles and carbon shells, markedly promote the reaction kinetics. The as-developed Fe@FeSA-N-C-900 electrocatalyst displays superior ORR performance with a half-wave potential (E1/2) of 0.83 V versus reversible hydrogen electrode (RHE) and a diffusion limited current density of 5.6 mA cm2. In addition, a rechargeable Zn-air battery device assembled by the Fe@FeSA-N-C-900 possesses remarkably stable performance with a small voltage gap without obvious voltage loss after 500 h of operation. The facile synthesis strategy for the high-performance composites represents another viable avenue to stable and low-cost electrocatalysts for ORR catalysis.
30 109/1 電機系 莊程豪 教授 期刊論文 發佈 Coexisting Single-Atomic Fe and Ni Sites on Hierarchically Ordered Porous Carbon as a Highly Efficient ORR Electrocatalyst , [109-1] 摘要:The development of oxygen reduction reaction (ORR) electrocatalysts based on earth‐abundant nonprecious materials is critically important for sustainable large‐scale applications of fuel cells and metal–air batteries. Herein, a hetero‐single‐atom (h‐SA) ORR electrocatalyst is presented, which has atomically dispersed Fe and Ni coanchored to a microsized nitrogen‐doped graphitic carbon support with unique trimodal‐porous structure configured by highly ordered macropores interconnected through mesopores. Extended X‐ray absorption fine structure spectra confirm that Fe‐ and Ni‐SAs are affixed to the carbon support via FeN4 and NiN4 coordination bonds. The resultant Fe/Ni h‐SA electrocatalyst exhibits an outstanding ORR activity, outperforming SA electrocatalysts with only Fe‐ or Ni‐SAs, and the benchmark Pt/C. The obtained experimental results indicate that the achieved outstanding ORR performance results from the synergetic enhancement induced by the coexisting FeN4 and NiN4 sites, and the superior mass‐transfer capability promoted by the trimodal‐porous‐structured carbon support.
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