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Photoelectrochemical (PEC) water splitting supplies an environmentally friendly, sustainable approach to generating renewable hydrogen fuels. Oxides semiconductors, e.g. TiO2, BiVO4, and Fe2O3, have been widely developed as photoelectrodes to demonstrate the utility in PEC systems. Even though significant effort has been made to increase the PEC efficiency, these materials are still far from practical applications. The main issue of metal oxides is the wide bandgap energy that hinders effective photons harvesting from sunlight. In solar spectrum, over 40% of the energy is located in the near-infrared (NIR) region. Developing sophisticated PEC systems that can be driven by NIR illumination is therefore essential. This review gives a concise overview on PEC systems based on the use of NIR-driven photoelectrodes. Promising candidates as efficient yet practical NIR-responsive photoelectrodes are suggested and discussed. Future outlooks on the advancement of PEC water splitting are also proposed.

A facile, environmentally benign antisolvent method has been developed to prepare for reduced graphene oxides (RGO)-wrapped ZnO nanocrystals with controlled RGO contents. Because of the high electrical conductivity of RGO, the photogenerated electrons at ZnO mostly transported to RGO, leaving positively charged photoexcited holes in ZnO to result in charge separation. The steady-state photoluminescence, time-resolved photoluminescence spectroscopy and photovoltage decay analysis were employed to investigate charge carrier dynamics and charge transfer behaviors of RGO-ZnO. The influence of RGO content on the charge dynamics and photoconversion efficiency of RGO-ZnO toward dye degradation and water splitting has been realized.

This work demonstrated that the incorporation of graphene quantum dots (GQDs) can greatly improve the photoelectrochemical (PEC) efficiency of CdSe-sensitized TiO2 nanorods (TiO2/CdSe), a TiO2-based visible light-responsive photoelectrode paradigm, for solar hydrogen production. For TiO2/CdSe, the accumulated holes at CdSe may induce photocorrosive oxidation to decompose CdSe, deteriorating the long-term stability of the photoelectrode and degrading the PEC performance. With the introduction of GQDs, the delocalized holes can further transfer from CdSe to the GQDs, which eases the hole accumulation at the CdSe sites, thus retarding photocorrosion. Compared to the binary TiO2/CdSe photoanode, the ternary TiO2/CdSe/GQD photoanode displays higher photocurrent and better photostability toward PEC hydrogen production. This superiority can be attributed to vectorial charge transfer and enhanced reaction kinetics provided by the introduction of GQDs. The findings from this work highlight the importance of the introduction of GQDs as a potential solution to the photocorrosion issue of chalcogenide-sensitized semiconductor photoelectrodes.

The authors demonstrate a high efficiency and high fidelity frequency beam splitter using coherent-state single photons and show how it can be used for operations or devices in long-distance quantum communication.

Organizations use teams to generate novelty and useful ideas; thus, studying knowledge sharing in a team setting is important. It is essential to understand what and which factors drive the team members' high-quality knowledge contribution in a team meeting. Drawing on theories of social exchange and social capital, this paper proposes and empirically tests how an individual's cost-benefit factors and team contextual factors interact in increasing the quality of knowledge contribution in an expanded group support system meeting; additionally, a laboratory experiment with 146 participants across 30 teams was conducted to test out the proposed research model. According to the results, team collaborative norms, team identification, and enjoyment in helping others are critical predictors of the quality of individuals' knowledge contributions in a team setting environment. Team collaborative norms and identification are also critical moderators of the quality of individuals' knowledge contributions. Specifically, when weak team collaborative norms exist, loss of knowledge power inhibits contributions of useful knowledge, and the reciprocity benefit motivates contributions of useful knowledge. Further, when weak team identification exists, codification effort inhibits contributions of useful knowledge, and economic reward motivates contributions of useful knowledge. These findings have significant implications for future research and practice.

This study reports mechanical properties of single-crystal pure gold toward for applications as movable components in micro-electrical-mechanical system (MEMS) inertial sensors requiring high sensitivity. Gold is commonly applied in electronic devices because of the excellent corrosion resistance, chemical stability, and conductivity. Recently, MEMS inertial sensors utilizing gold materials are reported to have low Brownian noise and high sensitivity while keeping the dimensions small by taking advantage of gold’s high mass density [1]. For design of electronic device, mechanical property characterization of the constituent material is essential. In general, mechanical strengths of metallic materials are governed by movement of the dislocation, and the dislocation movement is affected by the crystal orientation, grain boundaries, texture, impurities, etc. In addition to these, mechanical properties of metallic materials are affected by size of the sample used in the evaluation when the sample size is reduced to micro or sub-micro scale, which is known as the sample size effect [2]. This sample size effect would cause mechanical properties of micro-scale metallic materials to differ from those of bulk-size materials. Therefore, in order to make contribution to design of MEMS devices, the mechanical property characterization must be conducted using specimens having dimensions and deformation system alike components used in MEMS. Micro-bending test is suggested to be the most suitable micro-mechanical property characterization method toward MEMS devices since movable components in a MEMS device would experience both compressive and tensile stresses during operation. Regarding the sample size effect, the strength has a power-law relationship with cross-sectional area of the specimen [2]. In bending test, the loading direction is perpendicular to the cantilever’s width direction and parallel to the thickness direction. Because of this, the width and the thickness are expected to affect the sample size effect differently. On the other hand, the dislocation movable is also highly affected by the grain boundary and eventually the sample size effect [3]. Hence, single crystalline specimen is often used to examine the sample size effect to eliminate influences from the grain boundary. In this study, micro-cantilevers composed of single-crystal pure gold were fabricated using focus ion beam (FIB). All micro-cantilevers were ensured to have the loading direction parallel to the [1-10] orientation and the neutral plane parallel to the [110] orientation. Lengths of the micro-cantilevers were fixed at 50 μm. The thicknesses and widths were varied between 5 to 15 μm. The bending test was performed using a machine specially designed for micro-specimens developed in our group as shown in Fig. 1. The strain rate was fixed at 0.125 %/sec. Fig. 2 shows scanning electron microscope (SEM) images of the 50×9.7×10.5 μm3 micro-cantilever before and after the micro-bending test. From these images, slip lines and necking were observed at the base of the cantilever where stress and deformation were concentrated after the bending test. This slip lines indicated the active slip plane according to the Schmid’s law. The engineering stresses, σ, were calculated utilizing the Euler-Bernoulli beam theory [4]. The engineering strains are calculated from ratio of the d/y [5], where d is displacement of tip of the indenter. Fig. 3 shows engineering stress-engineering strain curves of the five micro-cantilevers. Yield stresses of the 6.9, 10.5, and 15.1 μm thick micro-cantilevers were 195, 175, and 128 MPa, respectively. Yield stress of the 4.7, 9.7, and 15.1μm width micro-cantilevers were 177, 175, and 183 MPa, respectively. These yield stresses were all lager than the value of bulk-size pure gold, which were results of the sample size effect. In addition, the yield stress increased as the thickness decreased, whereas it does not change much with the width reduction. This result suggested the sample size effect was only observed when changing the thickness, but not the width. These findings confirmed mechanical properties of micro-cantilevers were affected by the sample geometry, which is named as the sample geometry effect. [1] D. Yamane, T. Konishi, T. Matsushima, K. Machida, H. Toshiyoshi, and K. Masu, Appl. Phys. Lett. 104 (2014) 074102 [2] J.R. Greer, W.C. Oliver, W.D. Nix, Acta. Mater. 53 (2005) 1821-1830. [3] J.R. Greer and J.Th.M. De Hosson, Prog. Mater. Sci. 56 (2011) 654-724 (2011). [4] K. Asano, T.F.M. Chang, H.C. Tang, T. Nagoshi, C.Y. Chen, D. Yamane, H. Ito, K. Machida, K. Masu, M. Sone, ECS J. Solid State Sci. Technol., 8 (2019) P412-P415. [5] E. Demir, D. Raabe, F. Roters, Acta. Mater. 58 (2010) 1876-1886. Figure 1

In this study, we design a Cassegrain-based concentrator with tailored mirrors. The proposed concentrator comprises a primary optical element (POE) and a secondary optical element (SOE). The POE is a parabolic concave mirror and the SOE is a hyperbolic convex mirror. In order to achieve uniform irradiance distribution without a homogenizer, the POE is tailored and tilted to generate a uniform distribution by overlapping the energy well. The Cassegrain-based concentrator with tailored mirrors can achieve a geometric concentration ratio of 1236 × , a concentration ratio of 1034 × , an optical efficiency of 83.66%, an acceptance angle of ± 0.38 ∘ , a uniformity of 7.87, and an aspect ratio of 0.254.

In this paper, we design a three-stage Fresnel lens concentrator with a low f number. The proposed concentrator consists of a primary optical element (POE) and a second optical element (SOE). The nine-sector three-stage Fresnel lens is composed of three types of triangular prisms: the refractive triangular prism, single total internal reflection triangular prism, and double total internal reflection triangular prism. In order to increase the uniformity and acceptance angle of the POE coupled to the SOE, the SOE is also divided into nine sectors. Finally, it is found that this nine-sector three-stage Fresnel lens concentrator can achieve a concentration ratio of 1000×; the uniformity is 25.8, optical efficiency is 81.8%, f number is 0.46, and acceptance angle is ±0.73°.

This study presents a simple, rapid, and low-cost sputtering system for the deposition of Ag-nanoparticles (Ag-NPs) in polymer light-emitting diodes (PLEDs) at room temperature. Proposed PLED structures based on Ag-NPs/GZO/PEN (AGP) and GZO/Ag-NPs/PEN (GAP) anodes are discussed. Because of surface-plasmon-enhanced emission, the electroluminescence intensities of PLEDs based on AGP anodes increased nearly 3.4-fold compared to normal PLEDs without Ag-NPs.

The performance of optical wireless communication (OWC) links based on the spectral amplitude encoding (SAE) of a broad-band spatially partially coherent beam through atmospheric turbulence is analyzed. It has been found that the power efficiency of transmitters of OWC links based on the non-uniform SAE is higher than that based on the uniform SAE. Further, the spectrum division method for the non-uniform SAE of broad-band beams has been proposed. The non-uniform SAE of a broad-band spatially partially coherent beam is an effective method to reduce the performance degradation of OWC links caused by atmospheric turbulence.

Helicobacter pylori is an important risk factor of duodenal ulcer (DU). Although many virulence factors of H. pylori have been identified, few have been reported to show an association with the pathogenesis of DU. The aims of this study were to identify H. pylori antigens showing a high seropositivity in DU and to develop a platform for rapid and easy diagnosis for DU. Because DU and gastric cancer (GC) are considered clinical divergent gastroduodenal diseases, we compared two-dimensional immunoblots of an acid-glycine extract of an H. pylori strain from a patient with DU probed with serum samples from 10 patients with DU and 10 with GC to identify DU-related antigens. Of the 11 proteins that were strongly recognized by serum IgG from DU patients, translation elongation factor EF-G (FusA), catalase (KatA), and urease alpha subunit (UreA) were identified as DU-related antigens, showing a higher seropositivity in DU samples (n = 124) than in GC samples (n = 95) (FusA, 70.2 versus 45.3%; KatA, 50.8 versus 41.1%; UreA, 44.4 versus 27.4%). In addition, we found that the use of multiple antigens improved the discrimination between patients with DU and those with GC as the odds ratios increased from 1.82 (95% confidence interval (CI), 0.79-4.21; p = 0.1607) for seropositivity for FusA, KatA, or UreA alone to 4.95 (95% CI, 2.05-12.0; p = 0.0004) for two of the three antigens and to 5.71 (95% CI, 1.86-17.6; p = 0.0024) for all three antigens. Moreover a protein array containing the three DU-related antigens was developed to test the idea of using multiple biomarkers in diagnosis. We conclude that FusA, KatA, and UreA are DU-related antigens of H. pylori, and the combination of these on a protein array provided a rapid and convenient method for detecting serum antibody patterns of DU patients.

In Taiwan, about 80 % information security services companies are system integration services provider. In the era of recession, system integration service companies are not only promising, there are also a large job market in Taiwan. This research use Modified Delphi and AHP to study core competence and core competence relationship between four information security service specialists working in system integration service provider. The results provide statistics to be reference by industries and academic.

Mobile data usage is on the rise globally. In emerging regions, mobile data is particularly expensive and suffers from the lack of price and data usage transparency needed to make informed decisions about Internet use. To measure and address this problem, we designed SmartBrowse, an Internet proxy system that shows mobile data usage information and provides controls to avoid overspending. In this paper, we discuss the results of a 10-week study with SmartBrowse, involving 299 participants in Ghana. Half the users were given SmartBrowse, and the other half was given a regular Internet experience. Our findings suggest that, compared with the control group, using SmartBrowse led to a significant reduction in Internet credit spend and increased online activity among SmartBrowse users, while providing the same or better mobile Internet user experience. Additionally, SmartBrowse users who were prior mobile data non-users increased their webpage views while spending less money than control users. Our discussion contributes to the understanding of how forward-looking ICTD research in the wild can empower mobile data users, in this case, through increased price transparency.

Background The aim of this study was to assess the treatment results and toxicity profiles of helical tomotherapy (HT) for postoperative high-risk oral cavity cancer. Methods From December 6, 2006 through October 9, 2009, 19 postoperative high-risk oral cavity cancer patients were enrolled. All of the patients received HT with (84%) or without (16%) chemotherapy. Results The median follow-up time was 17 months. The 2-year overall survival, disease-free survival, locoregional control, and distant metastasis-free rates were 94%, 84%, 92%, and 94%, respectively. The package of overall treatment time > 13 wk, the interval between surgery and radiation ≤ 6 wk, and the overall treatment time of radiation ≤ 7 wk was 21%, 84%, and 79%, respectively. The percentage of grade 3 mucositis, dermatitis, and leucopenia was 42%, 5% and 5%, respectively. Conclusions HT achieved encouraging clinical outcomes for postoperative high-risk oral cavity cancer patients with high compliance. A long-term follow-up study is needed to confirm these preliminary findings.

This paper describes the process of designing an enterprise application that connects employees, the unique interface challenges, research activities, and subsequent changes to the design. The user-centered design process was driven by three research activities that informed the design in stages. Focus group sessions enabled us to understand requirements, wireframe usability evaluations helped us to validate macro level design decisions, and live prototype testing provided feedback that helped refine the design and validate the interactions. The collective research activities contributed to improved usability for navigation, actions, search, and a hierarchical organization chart. In addition, social networking within the work context was better understood and important concerns were identified. Key changes to the design included a streamlined three-level organization chart, the reduction of icons, and a new layout for search.

In this paper, we show a whispering gallery mode coupler utilizing a side-tap structure. Here we choose a microsphere as the resonator. We fabricate this device by standard photolithography. Therefore, it is a on-chip optical device. The coupling efficiency can be as high as 26% by simulation. We fabricate the waveguide by photolithography to increase the stability and mechanical strength. In the end, we also check the physical tolerance and wavelength selectivity.

We describe our process, findings, and resulting solution for the CHI2005 Student Competition. The design problem was the issue of well-being of persons above the age of 65 years. Loss of a companion can be a primary cause of depression, and decline of social well-being and health for the elderly, so the challenge is to design for "artificial" companionship to support the elderly. We met this challenge by employing extensive research in geriatric psychology, empirical and analytical human-computer interaction methods, interaction design techniques, and technologies currently available or in development. Our solution is a wearable and stationary device that will allow the user to 1) record events through pictures and audio for sharing, 2) gather artifacts of their past such as photographs into a multimedia slideshow format for sharing with others, and 3) allow friends and family to be aware of the user's location for safety purposes.

For more colorful and low cost, this paper develops a rich color photo-addressing simple structure Roll-to-Roll electronic paper with improved materials. By photo-addressing, the reflected light wavelength of the developed electronic paper can shifted more than 210nm from blue to red to display rich-color images with much wider color gamut.

Background Stereotactic body radiation therapy (SBRT) applied by helical tomotherapy (HT) is feasible for lung cancer in clinical. Using SBRT concurrently with erlotinib for non-small cell lung cancer (NSCLC) is not reported previously. Case Presentation A 77-year-old man with stage III NSCLC, received erlotinib 150 mg/day, combined with image-guided SBRT via HT. A total tumor dose of 54 Gy/9 fractions was delivered to the tumor bed. The tumor responded dramatically and the combined regimen was well tolerated. After concurrent erlotinib-SBRT, erlotinib was continued as maintenance therapy. The patient developed dyspnea three months after the combined therapy and radiation pneumonitis with interstitial lung disease was suspected. Conclusions Combination SBRT, HT, and erlotinib therapy provided effective anti-tumor results. Nonetheless, the potential risks of enhanced adverse effects between radiation and erlotinib should be monitored closely, especially when SBRT is part of the regimen.