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Sulfuric-acid neutralization by motor oils in the presence of ethanol was investigated for the first time by quantitatively visualizing the fate of acid drops in five off-the-shelf commercial motor oils via capillary video-microscopy. For all the oils at room temperature, there was neutralization when ethanol was absent, whereas little neutralization was exhibited when ethanol was present. A very different behavior was exhibited at 100 °C, with rate of acid neutralization being much faster in the presence of ethanol than in absence. With 1% ethanol and temperature of 100 °C, acid droplets were neutralized in 2 min, whereas at room temperature droplets expanded ∼35% in diameter after 60 min with little neutralization. The reported phenomena may affect engine behavior and tribology.

A model liquid hydrocarbon (n-hexadecane) was used to gain insight on the mobilization of non-aqueous phase liquids (NAPLs) trapped in porous formations, important for both enhanced oil recovery (EOR) and oil spill remediation in porous media. Food-grade surfactants lecithin from soy and tween 80 were compared to commercial dispersant Corexit 9500A, for their ability to mobilize the hydrocarbon originally trapped in a water-filled cryolite porous medium. Red dye was added to the n-Hexadecane to improve visualization, and the aqueous phase incorporated different ratios of the surfactants Lecithin and Tween 80 to seek synergistic benefits when the two surfactants are combined. Visual-microscopic flooding experiments carried on a miniature packed bed produced images which were then analyzed using grayscale image analysis. It was determined that a ratio 40:60 by weight of Lecithin to Tween 80 has the best performance in the mobilization of n-hexadecane from the porous media. Furthermore, any (non-optimal) mixture of lecithin and tween 80 exhibited a better (synergistic) performance in n-Hexadecane recovery from the porous media than when applying either surfactant separately.

This work highlights the fabrication of nickel‑copper/titanium nitride (Ni-Cu/TiN) for the use in direct methanol fuel cells. Ni-Cu nanoparticles are coated on the surface of TiN film by electrochemical methods. The formation of Ni-Cu/TiN is confirmed by a variety of means such as field-emission scanning electron microscopy and atomic force microscopy. The presence of Ni-Cu on TiN film is further confirmed by cyclic voltammetry. For the electrochemical oxidation of methanol, the electrocatalytic activity of the prepared Ni-Cu/TiN is higher than those of Cu/TiN, Ni/TiN, Ni-Mn/TiN, and Ni-Co/TiN. The stability for the electrochemical oxidation of methanol at Ni-Cu/TiN is better than that of Ni-Cu/glassy carbon electrode. The proposed Ni-Cu/TiN might be beneficial to develop high performance and low manufacturing cost of direct methanol fuel cells.

This paper presents the fabrication of polyaniline and graphene oxide aerogel composite (PGA) thin film-based sensors for H2S gas sensing application. The optical and morphological properties of these composite films were characterised correspondingly by UV–visible spectroscopy and scanning electron microscopy. To prepare the gas sensors, thin films of PANI and PGA composites were deposited onto interdigitated electrodes by spin coating method. The response of these sensors towards H2S gas was evaluated by monitoring the change in electrical conductivity at room temperature under two relative humidity values of 60% RH and 80% RH. The PGA composite thin film-based gas sensors showed a higher response compared with the pure PANI-based sensor. The gas sensor made of PGA-3 showed a good response of 3.87 in 67 s (60% RH), which is 4.6 times higher than that of pure PANI and 2.5 times higher than that of PGA-1 at 1 ppm. The first-principles simulations were carried out to investigate the H2S sensing mechanism of PGA heterostructure. The adsorption of H2S at different locations of pure PANI and PGA composites was analysed. The band gap for PGA showed more significant change after adsorption than that of pure PANI, which indicated the higher sensitivity for detecting H2S.

The southern Central Range of Taiwan is in an early stage of orogeny and the landscape has not yet reached a steady state. To reveal the nature of the transient landscape and its evolution towards a steady state during orogeny, we conducted an in-situ 10Be cosmogenic nuclide study together with geomorphic analyses to characterize the spatial pattern of erosion rate at the scale of individual catchments. Sediment samples were collected at outlets of major basins, and within nested sub-basins. Basin-wide erosion rates were estimated from 10Be concentrations and basin mean 10Be production rates. The erosion rates of major basins show a northward increasing trend, which is consistent with the pattern of mean basin channel steepness, reflecting the early stage of orogeny and indicating that the landscape is evolving in response to tectonic forcing. However, nested samples reveal significant spatial variability in erosion rate at the sub-basin scale. These spatial variations are consistent with predictions of divide motion from χ analysis and other geomorphic metrics including cross-divide asymmetry. These suggest that the main divide is moving towards the west in southernmost Taiwan. We also found evidence of internal basin reorganization with several cases of growing basins at the expense of neighboring basins. These findings imply that even though tectonic forcing dominates the large-scale patterns, basin reorganization is a significant process affecting spatial patterns of erosion rate at the smaller scale, so that topographic steady state is likely to be found only for the largest characteristics of the landscape.

In this study, we developed an overlay coating of high-entropy alloy (HEA) NiCo 0.6 Fe 0.2 Cr 1.5 SiAlTi 0.2 (C3) via atmospheric plasma spraying. The as-deposited coating is a supersaturated BCC phase except some oxide stringers formed during the spray. However, a plenty of Cr 3 Si phase forms in the coating and cause a large increase of hardness and wear resistance when aged at 800 and 1100 °C. The oxidation weight gain test demonstrates that the coating exhibits oxidation resistance as good as typical NiCrAlY coating at 1100 °C due to the formation of a dense thermally grown oxide layer (TGO) comprising Al 2 O 3 and Cr 2 O 3 . This coating becomes a strong candidate for high-temperature protective layer requiring oxidation and wear resistance.

We derive erosion rates from detrital zircon fission-track ages and cosmogenic nuclide concentrations from sediments from the modern rivers of eastern Taiwan in order to investigate how surface erosional processes vary in space and time across the young arc-continent collisional orogen of Taiwan. Taiwan is characterized by rapid rates of exhumation, a fluvial and landslide-dominated landscape, high seismicity, high relief and frequent typhoons. The obliquity between the convergence direction and the trend of the plate boundary provides a gradient in uplift and variations in longevity of orogenic activity with a young, immature orogen in the south, a mature orogen in central and northern Taiwan, and perhaps even the cessation of orogeny in the far north. The modern zircon fission-track detrital record is consistent with basement ages that show that much of the orogen is eroding at high rates with basin-wide mean zircon fission-track cooling ages as young as 0.9 Ma. The erosion rates derived from concentrations of cosmogenic nuclides ( 10 Be) provide erosion rates averaged over much shorter timescales, but these two proxies provide estimates of erosion rates that are within error of each other across most of the collisional belt. Erosion rates are lowest in the immature zone of the orogen (

In this work, the effects of nitrous oxide plasma treatment on the negative bias temperature stress of indium tin zinc oxide (ITZO) and indium gallium zinc oxide (IGZO) thin film transistors (TFTs) were reported. ITZO TFTs were more suitable for the back channel etched-type device structure because they could withstand both Al- and Cu-acid damage. The initial threshold voltage range could be controlled to within 1 V. The root cause of poor negative bias temperature stress for ITZO was likely due to a higher mobility (∼3.3 times) and more carbon related contamination bonds (∼5.9 times) relative to IGZO. Finally, 65″ active-matrix organic light-emitting diode televisions using the ITZO and IGZO TFTs were fabricated.

We have investigated the role of temperature in the degradation of GaN High-Electron-Mobility-Transistors (HEMTs) under high-power DC stress. We have identified two degradation mechanisms that take place in a sequential manner: the gate leakage current increases first, followed by a decrease in the drain current. Building on this observation, we demonstrate a new scheme to extract the activation energy (Ea) of device degradation from step-temperature measurements on a single device. The Ea’s we obtain closely agree with those extracted from conventional accelerated life test experiments on a similar device technology.

Background and aim Atrial fibrillation (AF) is an important cardiovascular disease in the elderly. The association between hyperuricemia and AF is unclear. Therefore, we aimed to investigate the prospective relationship between uric acid and development of AF in a nationally representative cohort of elderly people. Methods and results A total of 1485 elderly people (age ≥ 65 yrs) from the Elderly Nutrition and Health Survey in Taiwan (1999–2000) were without AF on “electrocardiography” at baseline. Incident AF events (International Classification of Diseases, Ninth Revision, Clinical Modification, ICD-9-CM: 427.31) were identified using data from the National Health Insurance Dataset. Hyperuricemia was defined as levels of uric acid >7.0 mg/dL in men and 6.0 mg/dL in women. A Cox proportional hazards model was used to evaluate the association between hyperuricemia and incident AF. The follow-up period was from 1999 to 2000 to 2008. During the follow-up period (median: 9.16 yrs), 90 AF events occurred (44 in men and 46 in women). Older age, elevated systolic blood pressure, being an ex-smoker, and high uric acid were positively associated with incident AF. Hyperuricemia was positively associated with incident AF in normotensive (age-adjusted hazard ratio (HR): 2.65 and 95% confidence intervals: 1.05–6.69), but not in (1.20:0.74–1.94) hypertensive individuals (systolic blood pressure ≥130 or diastolic blood pressure ≥85 or using hypertensive medicine). A significant association between hyperuricemia and AF (3.78; 1.24–11.59) remained after adjusting for other potential confounders among normotensive older persons. Conclusion Hyperuricemia is associated with the development of AF in elderly people with normal blood pressure.

Background and aim: Body mass index (BMI) has a U-shaped relationship with mortal- ity among the elderly, in contrast to the general adult population. Skeletal muscle mass may be more appropriate than BMI for classifying mortality risk among the elderly. We investigated the relationship between skeletal muscle mass and mortality among elderly Chinese persons. Method and results: A total of 1512 elderly from the Nutrition and Health Survey in Taiwanese Elderly (1999e2000) was enrolled, and the survival status was followed using data from the Na- tional Death Registry. The skeletal muscle mass index (SMMI) was calculated by dividing skeletal muscle mass by height in meters squared. The Cox proportional hazard model was used to esti- mate the association between SMMI and mortality. During the follow-up (average time: 7.9 years), one-third elderly died (n Z 506) by any cause and 25% of them was cardiovascular mor- tality (ICD-9-CM: between 390 and 459). The total mortality and cardiovascular mortality were 4.23 and 1.07 per 100 person-years. Elderly participants with the lowest SMMI had the highest total mortality and cardiovascular mortality among the four quartiles (6.72, 3.76, 3.25 and 3.50 per 100 PY for total mortality; 1.81, 0.76, 0.87, 0.93 for cardiovascular mortality). Those with a low (1st quartile) SMMI had a 2-fold increase in total mortality (1.96; 1.63e2.35) and cardiovas- cular mortality (2.16; 1.51e3.08) risk compared to those with a normal (2nd, 3rd, or 4th quartile) SMMI. Conclusions: The threshold relationship between SMMI and mortality is contrast to the reverse J- shaped relationship between BMI and total mortality. Therefore, skeletal muscle mass measure- ment may be considered with a high priority to identify elderly individuals with a high mortality risk.

The volumes of alkaline (pH > 10), Bacillus thuringiensis Cry protein-solubilizing buffers imbibed by fall armyworm larvae in droplet feeding assays were determined. The buffers differed in the presence or concentration of key ingredients, including buffering agents, chelating agents, reducing agents, and protease inhibitors. For both first and second instar larvae, the buffer used had a significant effect on the volume imbibed. The study showed that the droplet feeding method is compatible with Cry protein-solubilizing buffers, but that it is important to determine the volume imbibed for every buffer used in dose-dependent bioassays in order to reduce dose errors.

We have successfully fabricated large sized amorphous indium–gallium–zinc-oxide based active-matrix liquid-crystal displays, which uses Molybdenum/Aluminum/Titanium as source/drain electrode. In this study, an oxygen-rich etch stop layer acts as the oxygen atom supplier and converts the titanium layer into titanium oxide layer, which is found to induce instability of the device. Sample without titanium oxide has an initial threshold voltage shift is less than ±0.1 V after the repeatedly measuring over a period of two weeks. In addition, the IGZO based device demonstrated superior transfer characteristic. This paper established that the stability of the amorphous indium–gallium–zinc-oxide based active-matrix liquid-crystal display can be predicted by Stretched-Exponential model.

The use of electronic ticketing has grown rapidly since the mid-1990s because of the savings in ticket distribution costs and handling overheads it offers compared to paper tickets. Most airlines have attempted to make electronic tickets the default ticketing method. This study uses an intention model for electronic ticketing that tests whether its intended adoption is a function of attitude, social support, and perceived confidence of air travelers. The results indicate that over 70% of passengers are likely to use electronic tickets; moreover, over 90% of current users have intentions to continue to use them on international flights.

With rapid development of the Internet, e-learning system has become more and more popular. Currently, to solve the issue of sharing and reusing of teaching materials in different e-learning system, Sharable Content Object Reference Model (SCORM) is the most popular standard among existing international standards. In SCORM standard, the Sequencing and Navigation (SN) defines the course sequencing behavior, which controls the sequencing, selecting and delivering of a course, and organizes the content into a hierarchical structure, namely Activity Tree (AT). However, the structures with complicated sequencing rules of Activity Tree (AT) in SCORM make the design and creation of course sequences hard. Therefore, how to provide a user-friendly authoring tool to efficiently construct SCORM compliant course becomes an important issue. However, before developing the authoring tool, how to provide a systematic approach to analyze the sequencing rules and to transform the created course into SCORM compliant are our concerns. Therefore, in this paper, based upon the concept of Object Oriented Methodology (OOM), we propose a systematic approach, called Object Oriented Course Modeling (OOCM), to construct the SCORM compliant course. High-Level Petri Nets (HLPN), which is a powerful language for system modeling and validation, are applied to model the basic sequencing components, called Object-Oriented Activity Tree (OOAT), for constructing the SCORM course with complex sequencing behaviors. Every OOAT as a middleware represents a specific sequencing behavior in learning activity and corresponding structure with associated sequencing rules of AT in SCORM. Thus, these OOATs can be efficiently used to model and construct the course with complex sequencing behaviors for different learning guidance. Moreover, two algorithms, called PN2AT and AT2CP, are also proposed to transform HLPN modeled by OOATs into a tree-like structure with related sequencing rules in Activity Tree (AT) and package the AT and related physical learning resources into a SCORM compliant course file described by XML language, respectively. Finally, based upon the OOCM scheme, a prototypical authoring tool with graphical user interface (GUI) is developed. For evaluating the efficiency of the OOCM approach compared with existing authoring tools, an experiment has been done. The experimental results show that the OOCM approach is workable and beneficial for teachers/instructional designers.

This paper develops a theoretical model and conducts an empirical analysis of the effects of complementary and parallel codesharing on the load factors of international airline operations. The analysis shows that, given the increased demand resulting from the expansion of a global network, only parallel codesharing leads to higher load factors, since parallel alliance airlines can supply fewer seats than their complementary counterparts. These results provide new insights into several managerial and policy issues about airline strategic alliances such as partner selection, cost savings, and supply coordination.

Background Many studies have investigated the association between markers for peripheral inflammation and risk of dementia, but the results have been conflicting. We aimed to evaluate the association between a specific inflammation marker, C-reactive protein (CRP), and dementia in an elderly Asian community cohort. Methods The cohort included 1436 individuals (ages 65 and older) from a national representative sample in Taiwan. Dementia incidence was identified using International Classification of Diseases , Ninth Revision codes for vascular dementia, Alzheimer disease, and nonvascular dementia. Baseline characteristics and CRP levels were determined. A Cox proportional hazard model and Fine and Grays model were adjusted for stroke and competing risk of death to estimate the association between inflammation and development of dementia. Results During 11.04 years (median) of follow-up, 607 individuals (50.77%) died and 260 individuals (18.11%) were diagnosed with dementia. Those with high CRP had a 55% higher risk of dementia (hazard ratio 1.55; 95% confidence interval 1.21–2.00) compared with those with normal CRP. After adjusting for possible confounding cardiovascular risk factors, high CRP was independently associated with vascular dementia but not Alzheimer disease. Conclusions In this prospective study of an elderly Asian community cohort with more than 10 years of follow-up, the baseline serum CRP level was associated with future development of vascular dementia, but not Alzheimer disease after adjusting for common cardiovascular risk factors, stroke, and competing risk of death.