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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.

Phosphodiesterase 5A1 (PDE5) is a key target for treating cardiovascular diseases and erectile dysfunction. Here, we report the crystal structure of PDE5 complexed with the sole second generation drug avanafil. Analysis of protein-drug interactions revealed the structural basis of avanafil's superior isoform selectivity. Moreover, a halogen bonding was observed between avanafil and a backbone carbonyl oxygen of an adjacent α-helix, whose contribution to inhibitory potency illustrates the feasibility of exploiting α-helix backbone in structure-based drug design.

Colletotrichum scovillei is a virulent pathogen and the dominant species causing anthracnose of chili pepper in many Asian countries. Three strains of this pathogen, Coll-524, Coll-153 and Coll-365, show varied virulence on chili pepper fruit. Among the three strains, Coll-365 showed significant defects in growth and virulence. To decipher the genetic variations among these strains and identify genes contributing to growth and virulence, in this study, comparative genomic analysis and gene transformation to verify gene function were applied. The genomes of the three strains were sequenced and Coll-524 had 1.3% and 1.5% more genes than Coll-153 and Coll-365, respectively. Compared to Coll-524 and Coll-153, Coll-365 had numerous gene losses including 33 effector genes that are distributed in different scaffolds and a cluster of 14 genes in a 34-kb genomic fragment. Through gene transformation, three genes in the 34-kb fragment were identified to have functions in growth and/or virulence of C. scovillei. Gene 15019 encoding a protein related to phospholipase A2-activating protein enhanced the growth of Coll-365. A combination of 15019 with one transcription factor gene 15022 and one C6 zinc finger domain-containing protein gene 15029 was found to enhance the pathogenicity of Coll-365. Introduction of gene 15215, which encodes a LysM domain-containing protein, into Coll-365 caused a reduction in the germination rate of Coll-365. In conclusion, the higher virulent strain Coll-524 had more genes and encoded more pathogenicity related proteins and transposable elements than the other two strains, which may contribute to the high virulence of Coll-524. In addition, the absence of the 34-kb fragment plays a critical role in the defects of growth and virulence of strain Coll-365.Author SummaryColletotrichum scovillei is a highly virulent and dominant pathogen causing anthracnose of chili that leads to significant economic loss in chili production in many Asia countries. In this study we focus on finding the gene differences of three C. scovillei strains with different pathogenicity in chili pepper infection and verifying the function of some genes in the lowest virulence strain. We sequenced them and did gene annotation and genome comparison. We setup a simple mathematical method to identify gene variations between strong and weak virulence strains. Our results show that the lowest virulence strain has less pathogenicity-related genes. We also found that the absence of 14 genes in a compact genomic fragment was part of the reason of growth and virulence defect of the lowest virulence strain. We identified four genes that play roles on fungal growth and/or virulence on chili pepper. We also found a group of effector genes that specifically appear in species collected form infected chili in C. acutatum species complex. Our research provides detailed information for why the three strains have different virulence on chili pepper.

In this work, defect-free and high mechanical strength nickel films are deposited at a high growth rate using a high concentration sulfamate bath for applications in fabrication of MEMS components. Effects of the applied current density on the morphology, average grain size, Vickers hardness, micro-mechanical property, and thickness distribution are studied. The average grain size is refined to a minimum value when the current density is increased from 10 to 20 mA/cm2. The finest grain size obtained is 349.8 nm. The grain refinement effect is a result of the promoted nucleation rate as the applied current density increased. When the current density is beyond 20 mA/cm2, overpotential of the nickel reduction reaction is lowered because of the promoted hydrogen evolution and causes coarsening of the average grain size. The film electroplated at 20 mA/cm2 shows a high growth rate at 0.296 μm/min, the highest Vickers hardness at 371 HV, and the yield stress evaluated by micro-compression test is 1.3 GPa. Relationship between the average grain size and the applied current density follows the Hall-Petch relationship well.

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.

The Gram-negative bacterium Pseudomonas taiwanensis is a novel bacterium that uses shrimp shell waste as its sole sources of carbon and nitrogen. It is a versatile bacterium with potential for use in biological control, with activities including toxicity toward insects, fungi, and the rice pathogen Xanthomonas oryzae pv.oryzae (Xoo). In this study, the complete 5.08-Mb genome sequence of P. taiwanensis CMS was determined by a combination of NGS/Sanger sequencing and optical mapping. Comparison of optical maps of seven Pseudomonas species showed that P. taiwanensis is most closely related to P. putida KT 2400. We screened a total of 11,646 individual Tn5-transponson tagged strains to identify genes that are involved in the production and regulation of the iron-chelator pyoverdine in P. taiwanensis, which is a key anti-Xoo factor. Our results indicated that the two-component system (TCS) EnvZ/OmpR plays a positive regulatory role in the production of pyoverdine, whereas the sigma factor RpoS functions as a repressor. The knowledge of the molecular basis of the regulation of pyoverdine by P. taiwanensis provided herein will be useful for its development for use in biological control, including as an anti-Xoo agent.

This paper develops a symmetric atmospheric plasma source integrated with electrospray ionization (ESI) tip as a dual-ion source for simultaneously detecting nonpolar and polar compounds using the ambient mass spectrometry. A cross-shaped tube with symmetric discharge electrodes is used to generate dielectric barrier discharge to produce ionized gas charging nonpolar molecules, while a coaxial capillary is placed at the center of the cross-shaped tube for generating electrospray discharge. Since there is no floating voltage at the outlet of the cross-shaped tube, the potential interference for the ESI can be excluded. Results show that dual-ion source can stably produce high-intensity ions of 109 ion $\cdot $ cm−3. Moreover, the relationship between the measured ion intensity and the gas flow rate, gas temperature, and applied voltage for ESI are systematically investigated. Various samples including volatile organic compounds, pesticides, Chinese herbal medicines, and vitamins are used for evaluating the sensing performance of the dual-ion source in plasma mode, electrospray mode, and dual-ion source mode, respectively. Results show that the developed dual source is efficient to simultaneously detect both the polar and nonpolar compounds.

In this research, micro-bending tests of electrodeposited gold with various crystal structure were conducted using micro-cantilever specimens with dimensions at 10 μm × 10 μm × 50 μm for design of gold-based movable structures in MEMS devices. The gold film fabricated by pulse-current electrodeposition with a sulfite-based gold electrolyte (PE-Su) had the finest average grain size, which was at 15.5 nm. The PE-Su gold micro-cantilever showed ductile deformation behavior and the highest yield stress, which was at 800 MPa, because of the grain boundary strengthening mechanism also known as the Hall-Petch relationship. The gold film fabricated by constant-current electrodeposition with a cyanide-based gold electrolyte (CE-Cy) had an average grain size at 17.6 nm. The CE-Cy gold micro-cantilever showed brittle fracture and the yield stress at 480 MPa. The brittle fracture was suggested to be a result of the columnar texture structure in the CE-Cy gold film.

Summary The Orchidaceae is a diverse and ecologically important plant family. Approximately 69% of all orchid species are epiphytes, which provide diverse microhabitats for many small animals and fungi in the canopy of tropical rainforests. Moreover, many orchids are of economic importance as food flavourings or ornamental plants. Phalaenopsis aphrodite, an epiphytic orchid, is a major breeding parent of many commercial orchid hybrids. We provide a high‐quality chromosome‐scale assembly of the P. aphrodite genome. The total length of all scaffolds is 1025.1 Mb, with N50 scaffold size of 19.7 Mb. A total of 28 902 protein‐coding genes were identified. We constructed an orchid genetic linkage map, and then anchored and ordered the genomic scaffolds along the linkage groups. We also established a high‐resolution pachytene karyotype of P. aphrodite and completed the assignment of linkage groups to the 19 chromosomes using fluorescence in situ hybridization. We identified an expansion in the epiphytic orchid lineage of FRS5‐like subclade associated with adaptations to the life in the canopy. Phylogenetic analysis further provides new insights into the orchid lineage‐specific duplications of MADS‐box genes, which might have contributed to the variation in labellum and pollinium morphology and its accessory structure. To our knowledge, this is the first orchid genome to be integrated with a SNP‐based genetic linkage map and validated by physical mapping. The genome and genetic map not only offer unprecedented resources for increasing breeding efficiency in horticultural orchids but also provide an important foundation for future studies in adaptation genomics of epiphytes.

Poor kinetics of hole transportation at the electrode/electrolyte interface is regarded as a primary cause for the mediocre performance of n-type TiO2 photoelectrodes. By adopting nanotubes as the electrode backbone, light absorption and carrier collection can be spatially decoupled, allowing n-type TiO2, with its short hole diffusion length, to maximize the use of the available photoexcited charge carriers during operation in photoelectrochemical (PEC) water splitting. Here, we presented a delicate electrochemical anodization process for the preparation of quaternary Ti–Nb–Ta–Zr–O mixed-oxide (denoted as TNTZO) nanotube arrays and demonstrated their utility in PEC water splitting. The charge-transfer dynamics for the electrodes was investigated using time-resolved photoluminescence, electrochemical impedance spectroscopy, and the decay of open-circuit voltage analysis. Data reveal that the superior photoactivity of TNTZO over pristine TiO2 originated from the introduction of Nd, Ta, and Zr elements, whic...

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 preparation and characterization of biocompatible, conductive, and flexible silk–Pt composite materials for applications in wearable and medical devices. The distinct Pt and silk materials were integrated via supercritical carbon dioxide (sc-CO2) promoted electroless plating. Sc-CO2 was introduced into the catalyzation step, which is a critical step in electroless plating, to overcome the common difficulty of inlaying the catalyst into the textile substrate. High surface coverage and thick Pt layer were constructed as the metallization time extended. Metal ions released in a simulated body fluid in an immersion test were negligible when compared to the daily metal input and output of the human body. The composites showed high corrosion resistances in both 3.5 wt % NaCl and simulated body fluid solutions. The electrical conductivity and corrosion resistance persisted after the adhesion tests. The assessments revealed the applicability of this silk–Pt material to wearable and medical devices.

The hydrobaric effect on photoactivity of titanium dioxide (TiO2) fabricated by cathodic deposition in an aqueous solution was evaluated in this study. When the applied pressure was increased to 35 MPa, the water-splitting performance was improved by almost fourfold of the performance of the TiO2 prepared at atmospheric pressure. The surface states effect was significant in the deposited TiO2, which was exploited to affect the charges recombination of TiO2, and thereby enhance the resultant photoelectrochemical water-splitting performance. The hydrobaric cathodic deposition could be extended to fabrication of other metal oxides to eliminate the negative influence from the high-temperature process.

In this study, the silicon-base net-like hollow nano-structure were prepared using single-nozzle electrospinning and heat treatment process. Firstly, a precursor solution is prepared by dissolving an appropriate amount of Polyvinylpyrrolidone (PVP) and Tetraethyl orthosilicate (TEOS) in ethanol and spinning the nanofibers using a single -nozzle electrospinning. Secondly, the morphology of electrospinning nanofibers was controlled, the temperature profile was designed to prepare hollow nanofibers, and the morphology and properties of nanofibers were explored. Molding with traditional methods, such as rapid freezing, 3D printing, and sintering. It is almost impossible to prepare fibers with diameters less than 1 μm. The electrospinning technology is simple in its production process and cab increase the hollow, high length, uniform diameter, and diverse components of the nano-fiber.Finally, the characteristic of nanofibers, following instruments were used: Atomic force microscopy (AFM), Field Emission Scanning Electron Microscope (FE-SEM), Transmission electron microscopy (TEM), X-ray Diffract-ion(XRD). The AFM was used to scan the nanofibers, and 3D Graphics was used to explore the surface morphology of fibers. Using FE-SEM and TEM system is to explore the morphology, diameter of nanofibers, and hollow nanofiber . The electrospinning technique followed by subsequent heat treatment is well developed so that we can successfully prepare silicon-based oxide nanofibers with the hollow structure. Thus, the microstructure and morphology of electrostatic spinning silicon-base oxide hollow nanofibers were explored, and also their crystalline properties and crystal structure were identified.

In this study, an electroless deposition method including catalyzation in supercritical carbon dioxide (sc-CO2) and plating in sc-CO2 emulsified electrolyte was applied in metallization of Nylon 6,6 textile. In order to demonstrate the effects of the sc-CO2, the catalyzation was conducted either by the conventional method or the supercritical CO2 catalyzation (SCC) method with bis (2,4-pentandionato)-palladium. After the catalyzation process, either the conventional electroless plating or the electroless plating with supercritical CO2 emulsified electrolyte (ELP-SCE) was performed. Surface of the Ni-P coatings on the Nylon 6,6 was observed by an optical microscope and a scanning electron microscope. The Ni-P coating by the conventional catalyzation and the conventional electroless plating showed some cracks, nodules and rough structure. The Ni-P coating by the SCC and the conventional electroless plating showed smooth Ni-P coating on the surface of each fibers and had some peeled-off parts. On the other hand, uniform Ni-P coating on the surface of each fibers was obtained by the SCC and the ELP-SCE. These results demonstrated that the SCC is effective to impregnate Pd catalysts into the fibers, and the ELP-SCE can inhibit the nodule growth of the Ni-P. Thus, the proposed method can metallize the surface of each Nylon 6,6 fibers and has potential to give some functions on textiles.

In this study, an electroless plating method involved Pt catalyzation in supercritical carbon dioxide (sc-CO2) and conventional Pt electroless plating was used for the metallization of polyamide 6,6 (PA66) textiles. The catalyzation was conducted either by conventional method at atmospheric pressure or in sc-CO2 with bis (2,4-pentandionato)-platinum. After the catalyzation process, the conventional Pt electroless plating method was performed for the Pt catalyzed PA66 textiles. Surface of the Pt coated PA66 was observed by an optical microscope and a scanning electron microscope. The Pt coating by the conventional catalyzation had a rough surface, and the surface did not show the textile outline because of the dissolution of the textile in the conventional catalyzation solution. The textile metallized by the sc-CO2 catalyzation showed a metallic bright coating, and the Pt coating was observed on the surface of each fiber. These results indicate that the sc-CO2 catalyzation is a promising method to catalyze the PA66 textile. Display Omitted Metallization of polyamide 66 (PA66) using supercritical CO2 (sc-CO2) was reported.Pt was used as the catalyst and coating to improve the biocompatibility.Pt catalyst seeds were formed by sc-CO2 catalyzation (SCC).Uniform Pt coating was formed by SCC follow by conventional electroless plating.The Pt coating was bright, defect-free and still showed outline of the PA66 fibers.

In recent years, MEMS (microelectromechanical systems) devices are required to have high functionality and small size, especially for MEMS acceleration sensors, and sensitivity of a MEMS acceleration sensor is highly dependent on the Brownian noise [1,2]. The Brown noise is known to be inversely proportional to mass of movable parts in the sensor, and the noise is lowered by increasing the mass [1,2], which implies a number of volume is needed to ensure high sensitivity. However, increasing size of the component is not preferable. Because of this, a design of gold-based MEMS acceleration sensor is proposed. The density of gold is 19.3 g/cm3, and gold has high corrosion resistance and chemical stability. Most importantly, gold electrodeposition process can be easily integrated with current MEMS fabrication process. Mechanical properties of the material are essential informtion for design of MEMS components. For instance, the yield stress is needed to guarantee elastic deformation of the material during operation of the MEMS device. Mechanical properties of metallic materials are known to change with size of the sample used in a mechanical property characterization becomes smaller than micrometer scale, which is known as the sample size effect [3]. Therefore, mechanical property characterization of materials toward MEMS should be conducted using samples having the same dimensions as those used in MEMS. Various micro-mechanical testing methods have been developed to characterize micro-specimens, such as micro-compression test, micro-tensile test, and micro-bending test. Among them, micro-bending test is suggested to be the most suitable method to evaluate materials for applications in MEMS when compared with micro-compression and micro-tensile tests since cantilever-like structure is commonly utilized in movable components, such as the micro-spring in MEMS accelerometers. On the other hand, micro-cantilevers are reported to have the sample geometry effect [4], which the sample size effect is only observed when varying thickness of the micro-cantilever. Also, it has been reported that the sample size effect is dependent on ratio of the sample diameter to the average grain size, and materials prepared by electrodeposition are usually polycrystal. Thus, relationship between the sample geometry effect and the average grain size is investigated in this study. Two gold films were electrodeposited at different current density to change the average grain size. The average grain size was determined by electron backscatter diffraction, and the average grain size of film A and B were 1.2~1.3 and 0.6 μm, respectively. Samples used in the micro-bending test were micro-cantilevers fabricated from the gold films by focus ion beam. Thicknesses of the micro-cantilever were ranged from 6.0 to 13 μm. The micro-bending tests are conducted using a test machine specially designed for micro-specimens developed in our group as shown in Fig. 1. The yield stresses were in a range of 428 to 553MPa, which were all higher than that of the bulk gold (55 to 220 MPa). Table 1 shows the detailed dimensions and yield stress of all samples. Yield stresses were plotted against the log scale of thickness shown in Fig. 2. At first, the sample geometry effect was confirmed in samples fabricated from both film A and B. Then, the yield stresses of samples fabricated from film B were all higher than those of film A, which was a result of the Hall-Petch relationship. In Fig. 2, the slop was steeper for film A indicating the sample geometry effect was more obvious in samples composed of larger grains. [1] D. Yamane, T. Konishi, T. Matsushima, K. Machida, H. Toshiyoshi, and K. Masu, Appl Phys Lett 104 (2014) 074102 [2] K. Machida, T. Konishi, D. Yamane, H. Toshiyoshi, K. Masu, ECS Trans. 61 (2014) 21-39. [3] J.R. Greer and J.Th.M. De Hosson: Plasticity in small-sized metallic systems: Intrinsic versus extrinsic size effect. Prog. Mater. Sci. 56, 654 (2011). [4] K. Suzuki, “Sample Geometry Effect on Mechanical Property of Electrodeposited Gold Evaluated by Micro-Bending Test", 45th International Conference on Micro & Nano Engineering (MNE2019), Rhodes Greece, Sep. 2019 Figure 1

Nickel [1], cobalt [2], and their alloys have been investigated as important engineering materials because of their unique properties, such as magnetic, heat-conductive and high hardness. Much interest is focused on the application of Ni-Co alloy films in micro-electrical-mechanical systems (MEMS) devices especially their considerable potential in manufacturing of magnetic actuator due to excellent electrical and mechanical properties [3]. Reliability of electronic components is highly dependent on the mechanical property, which is closely related to its average grain size according to grain boundary strengthening mechanism [4]. Nanocrystalline materials can offer enhanced mechanical strength compared with coarse-grained counterparts when device components are scaled to the micro-scale regime with synergistic effect of the sample size effect [5]. Meanwhile, alloying allows utilization of the solid solution strengthening mechanism to further enhance the mechanical strength [6], and Ni-Co forms a solid solution over the whole concentration range, making it easy to control the mechanical and magnetic properties. Electroplating is a promising technique in controlling crystalline properties of Ni-Co alloy films because the morphology, composition, grain size, and deposition rate of the deposited materials can be facilely controlled by varying the electroplating parameters, such as the current density, bath composition, and temperature [7]. Therefore, in this study, the effects of applied current density on average grain size, composition, and micro-mechanical properties of electrodeposited Ni-Co films are evaluated for fabrication of micro-components in electronic devices. The electroplating was carried out at 55 ℃, and the current density was varied from 5 to 20 mA/cm2. A piece of Pt plate was used as the anode. Crystalline structure of the Ni-Co films was characterized by X-ray diffraction (XRD), average grain size was determined using XRD in conjunction with the Scherrer method. Microhardness tests were conducted on a Vicker's hardness tester using a load of 0.025 kg, applied for 15 s. Composition was analysed by energy dispersive X-ray spectroscopy (EDX) system. Furthermore, alloy films are processed into micro-pillars in a size of 10×10×20 μm3with focused ion beam (FIB, FB2100, Hitachi) milling. The optical microscope photograph of Ni-Co alloy micro-pillar fabricated with current density of 18 mA/cm2 is shown in Fig. 1. A high yield stress of 1.65 GPa is determined after the micro-compression test. Vickers hardness as a function of d -1/2 for the alloy specimens is shown in the scatter plot of Fig. 2, where d is average grain size. Microhardness value has a positive linear relationship with d -1/2 approximately, which corresponds well to Hall-Petch relationship. Maximum Vicker's hardness value of 526 Hv was obtained with a current density of 10 mA/cm2, which is much higher than those of pure Ni (306 Hv) and Co (403 Hv) films prepared in this study, indicating the effect of solid solution strengthening. [1] T. Yamamoto, K. Igawa, H.C. Tang, C.Y. Chen, T.F.M. Chang, T. Nagoshi, O. Kudo, R. Maeda, M. Sone, Microelectron. Eng. , 213, 18 (2019). [2] X. Luo, C.Y. Chen, T.F.M. Chang, H. Hosoda, M. Sone, J. Electrochem. Soc. , 162, D423 (2015). [3] M. Duch, J. Esteve, E. Gómez, R. Pérez-Castillejos, E. Vallés, J. Micromech. Microeng. , 12, 400 (2002). [4] C.Y. Chen, M. Yoshiba, T. Nagoshi, T.F.M. Chang, D. Yamane, K. Machida, K. Masu, M. Sone, Electrochem. Commun. , 67, 51 (2016). [5] M. D. Uchic, D. M. Dimiduk, J. N. Florando, W. D. Nix, Sc ience , 305, 986 (2004). [6] H. Tang, T.F.M. Chang, Y.W. Chai, C.Y. Chen, T. Nagoshi, D. Yamane, H. Ito, K. Machida, K. Masu, M. Sone, J. Electrochem. Soc. , 165, D58 (2018). [7] A. Bai, C.C. Hu, Electrochimica Acta , 47, 3447 (2002). Figure 1

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.

Electrodeposited gold is used in movable micro-components of micro-electro-mechanical systems (MEMS) devices to allow further enhancement in the sensitivity and miniaturization of the device [1]. Mechanical strengths of gold are low among materials commonly used as structure materials in electronic devices. Electrodeposition method is advantageous in strengthening metallic materials because of the ability to refine the average grain size to nano-scale, which the mechanical strength increases along with a reduction in the grain size based on the grain boundary strengthening mechanism or the Hall-Petch relationship. Alloying of metallic materials is also an effective strategy to achieve the strengthening according to the solid solution strengthening mechanism. On the other hand, mechanical properties of metallic materials exhibit the sample size effect when dimensions of the specimen are reduced to micro or sub-micro scale. Therefore, mechanical property characterization of materials for MEMS applications should be conducted using specimens having dimensions in micro-scale. Various micro-mechanical testing methods have been developed in our group to characterize micro-specimens, such as micro-compression test [2,3], micro-tensile test [4], and micro-bending test [5]. Among them, micro-bending test is suggested to be the most suitable method to evaluate materials for applications in MEMS when compared with micro-compression and micro-tensile tests since cantilever-like structures are often applied in MEMS components, such as the micro-spring in a MEMS accelerometer. In this study, Au-Cu alloys are prepared by electrodeposition, and micro-mechanical properties of the electrodeposited Au-Cu alloys are characterized by a micro-bending test. Young’s modulus is an important information in design of movable micro-components. A non-destructive Young’s modulus evaluation method, resonance frequency measurement, is conducted using the Au-Cu alloy micro-cantilevers. Also, long-term vibration tests are conducted to reveal structure stability of the Au-Cu alloy micro-cantilevers. The Au-Cu electrolyte used in this work was a commercially available electrolyte provided by MATEX Co. Japan, which contained 17.3 g/L of X3Au(SO3)2 (X = Na, K), 1.26 g/L of CuSO4, and ethylenediaminetetraacetic acid as the additive with pH at 7.5. The electrodeposition was carried out at 50 °C, and the current density was varied from 0.1 to 8 mA/cm2. Specimens used in the micro-bending test were micro-cantilevers fabricated from the Au-Cu alloy films by focused ion beam. Dimensions of the micro-cantilevers fabricated were 10 µm × 10 µm × 50 µm. The micro-bending tests were conducted using a test machine equipped with a spherical diamond indenter at a constant displacement rate of 0.05 µm/s. For the Young’s modulus and long-term structure stability evaluations, the micro-cantilevers were prepared by electrodeposition combined with lithography process. The long-term vibration test was carried out under conditions of the cycle number in a range from 103 to 106, the frequency of 10.0 Hz, and the acceleration of 1.0 G (1 G = 9.8 m/s2). The structure stability was determined by evaluating height profiles of top surface of the micro-cantilevers before and after the vibration test by a 3D optical microscope. The Au-Cu alloy film electrodeposited at 5 mA/cm2 had the finest average grain size among films prepared in this work, which the grain size was 4.76 nm. Bending test of a micro-cantilever prepared from this film shows a high yield stress at 1826 MPa. Gold, copper, and Au-Cu alloys are known to be ductile materials, but brittle fracture was observed during the bending test when the current density used in prepared the film was higher than 5 mA/cm2. From the resonance frequency method, Young’s moduli of the Au-Cu alloy micro-cantilevers were ranged from 68.0 to 79.5 GPa, which were similar to the value of bulk-size specimens and indicated no sample size effect on the Young’s modulus. Regarding the long-term structure stability, after 106 cycles of the vibration test, all the micro-cantilever were still intact, and the height profiles did not change much after the vibration. Results obtained in this study confirmed high mechanical strength and structure stability in the electroplated Au-Cu alloys and demonstrated the advantage in applications as movable components in MEMS devices. [1] D. Yamane et. al. Appl. Phys. Lett. 104 (2014) 074102. [2] C.Y. Chen et. al. Electrochem. Commun. 51 (2016) 51-54. [3] H. Tang et. al. J. Electrochem. Soc. 164 (2017) 244-247 [4] Y. Kihara et. al. Mater. Lett. 153 (2015) 36-39 [5] K. Asano et. al. ECS J. Solid State Sci. Technol. 8 (2019) P412-P415.

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°.

Rapid drug release has become more important for the drug delivery system due to its rapid release, bioavailability and enhanced drug solubility. With a solid tablet an d a thin film as the design to enhance its rapid-release characteristics, to achieve this feature requires a highly porous network. Molding with traditional methods, such as rapid freezing, 3D printing, and sintering. It is almost impossible to prepare fibers with diameters less than 1 μm. The electrospinning technology is simple in its production process and inc reases the surface area, high length, uniform diameter and diverse components of the nano-fiber. In this study, three types of polymers, including Polyvinylpyrrolidone (PVP), Polysulfone (PES) and Polystyrene (PS), were mixed with Dimethylformamide (DMF) to form a precursor solution, which is used to prepare a large number of nanofibers through electrospinning method. Then with electrospinning method with vitamin C as the target molecule, nonwoven nanofibers were prepared. The experiment was carri ed out under the manipulation of field emission electron microscopy (FE-SEM), thermogravimetric loss analyzer (TGA), thermomechanical analyzer (TMA) and water droplet angle tester to analyze the properties of nanofibers and to explore the drug release. After placing in the air for different durations, because of the water vapor and the their own nature of the nanofiber that enable itself to shrink, the nanofiber would lose its nano-nature through a long time of shrinking, which led to the deceleration of dissolution, and thus made it easier to contro l its release rate[1-8].

Novel three-dimensional hierarchical heterostructures composed of two-dimensional SnS 2 nanoflakes and zero-dimensional SnO 2 nanoparticles were fabricated via a one-step hydrothermal method. Size of the heterostructures was ca. 2 μm in diameter, and individual SnS 2 nanoflakes with thickness of ca. 150 nm were connected to central core of the heterostructures. The SnO 2 nanoparticles in a diameter of ca. 5 nm uniformly covered entire surface of the SnS 2 nanoflakes. Moreover, both of these structures were highly crystalline. Meanwhile, amorphous carbon was formed within the heterostructures. The SnS 2 /SnO 2 /C hierarchical heterostructures had a high initial specific reversible capacity of 1065.7 mAh g −1 , stable cycling stability of 638 mAh g −1 after 30 cycles, and superior rate capability of 550.8 mAh g −1 at 1C rate. These SnS 2 /SnO 2 /C hierarchical heterostructures showed better performance than individual SnS 2 and SnO 2 nanomaterials, and the performance was even higher than the graphene–SnS 2 and graphene–SnO 2 nanohybrid materials. This is attributed to a synergistic effect of high surface area, which is provided by the unique SnS 2 internal nanoflake layered structures decorated with ultra-fine SnO 2 nanoparticles, and an effective beneficial buffer matrix to accommodate the large volume change upon cycling, which is caused by the side-products such as Li 2 S or Li 2 O. The SnS 2 nanoflake was deduced to play a similar role as graphene material, since both possess 2D conducting layer structures. The uniform carbon dispersion within the structures also stabilizes the structures and improves electrical conductivity of the hierarchical heterostructures.

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.

We report an unconventional electrochemical spontaneous oscillation of current in Ti anodization by adding deep eutectic solvent (DES) of 2–10% to a fluoride-containing electrolyte; nanobamboos (NBs), i.e., nanotubes decorated with periodic exterior rings, were formed by the DES-assisted anodization. Spontaneous formation of NBs occurred upon application of a constant 20 V voltage, together with a self-induced current oscillation that corresponds well to the NB structures. The initial voltage must be higher than a threshold of approximately 14 V to induce the self-organization of the NBs. Once a dense layer of TiO2 is formed at 10 V or lower, formation of the NBs is suppressed even when a higher voltage (above 15 V) is applied. The NBs formed with the spontaneous current oscillation were densely packed (ca. 1.54 × 1010 cm−2) with each NB possessing many rings spaced 20–35 nm apart. The thickness of each ring was ca. 10 nm. By increasing the DES concentration to 10 wt%, the diameter of the NBs increased from 45 to 110 nm and their growth rate increased from 0.16 to 0.3 μm/h. The spontaneous current oscillation we observed differs from the conventional electrochemical oscillation because (1) oscillation period is quite long (7 min) and (2) the oscillation results in the periodic modulation of TiO2 NBs. The self-organized nanobaoboos were characterized for various anodization conditions, and a mechanism was proposed with the basis of the high conductivity and high viscosity of DES.

Magnetic shape memory alloys (MSMAs) are expected to be implemented into micro actuators and sensors because they have a large magnetic field induced strain combined and high response frequency. On the other hand, when dimensions of metallic materials are reduced from a bulk size to the micrometer scale, the mechanical response would vary along with the dimension change. Therefore, it is important to evaluate the mechanical properties of microscale specimens of shape memory alloys to be implemented in miniaturized devices. In the present work, the superelastic properties of the single crystal of Ni 50 Fe 19 Co 4 Ga 27 (at.%) MSMA have been studied by a micro-compression testing. The specimens were micropillars, fabricated by a focus ion beam technique. The compression stress-strain hysteretic dependences show typical superelastic behavior in a wide temperature range alongside a tendency to disappearance of hysteresis near the critical point at about 373K. The temperature shifts the martensitic transformation start stress with a rate of ∼1.1 MPa/K, which is similar in value to the bulk alloy. Thus, the studied alloy could retain the superelastic properties, including in a postcritical region, down to microscale.

This paper presents evaluation of the effective Young's modulus of electroplated gold micro-cantilevers. Young's modulus is one of the fundamental parameters to design MEMS (microelectromechanical systems) components. Gold electroplated MEMS structures can be used to develop highly-sensitive MEMS sensors, such as accelerometers. With a resonant frequency method, we evaluate gold-electroplated Ti/Au cantilevers by varying both the length and the width. The experimental results showed that the Young's modulus was dependent on the width, and it was found that the Young's modulus increased with an increase in the width, which would be useful to design MEMS devices.

This paper develops a novel symmetric dielectric barrier discharge (DBD) plasma as an ion source for environmental mass spectrometry (MS) applications. The conventional linear-type DBD plasma generator suffers the drawback of floating voltage at the plasma outlet. This paper develops an innovative symmetric T-shaped DBD plasma generator to produce atmospheric plasma with zero-floating potential for high-sensitivity MS analysis. By changing the geometric configuration and the drive phase of the symmetric T-shaped DBD plasma generator, the resulting symmetric structural design can fully cancel the floating potential and noise signal. Therefore, the main objective of this paper is to compare the differences between traditional linear-type DBD and the symmetric T-shaped DBD designs using MS, spectroscopy, and some basic electrical measurements. The most suitable parameters are determined by changing the electrode design, voltage, temperature, gas flow rate, diameter, and other parameters of the plasma tube. The symmetric T-shaped design generator produces the zero-potential plasma that generates fewer ambient gas molecules to form ozone, NOx, water clusters, and other strong oxidizing molecules such that less damage to the MS samples occurs. This in turn results in a less fragmented ion signal and higher sensing performance for rapid MS applications. In addition, the proposed system can directly ionize gas, liquid, and solid samples at more than $10^{7}$ -cm$^{-3}$ ion concentration. Results show that more information-rich spectra can be obtained with the developed symmetric T-shaped DBD plasma generator compared with the typical linear-type DBD generator.

Sn/SnO2 composite materials are promising anode materials in lithium ion battery. Electrodeposition with supercritical CO2(sc-CO2) emulsified electrolyte (EP-SCE) is an effective method in controlling morphology (Ni [1], Cu[2], and Co[3]) and crystallinity (ZnO [4]and TiO2 [5]) of electrodeposited materials. Sc-CO2 is CO2 at temperature and pressure above its critical point, which is 304.1 K and 7.38 MPa. CO2 is non-polar, therefore, the solubility of metal salts and electrical conductivity are both very low in sc-CO2. In order to conduct electrochemical reactions, surfactants are used to form emulsified electrolyte. Co-deposition of SnO2 along with electrodeposition of metallic Sn can occur at the same time in a SnCl2 based electrolyte containing NO3 - ions [6]. The EP-SCE is expected to be effective in controlling concentration and properties of the SnO2 in metallic Sn film. In this study, Sn/SnO2 composite films are prepared by electrodeposition with supercritical CO2 (sc-CO2) emulsified electrolyte, and the mechanical properties in micro-scale are evaluated by compression test of micro-pilliars fabricated from the Sn/SnO2 composite film for practical applications. Details of the high pressure electrochemical apparatus can be found in a previous study [1]. The electrolyte is composed of 0.22 M SnCl2, 0.015 M HCl and 0.31 M (NH4)3C6H5O7. The current density applied is varied from 2.8 to 17.3 mA/cm2. For the EP-SCE, the surfactant is C12H25(OCH2CH2)15OH. 0.2 vol.% of the surfactant is used to form the sc-CO2 emulsions. 20 vol.% of CO2 at 343 K and 15 MPa under agitation are used to ensure the formation of a stable emulsion. Electrodeposition without the sc-CO2 emulsions at ambient condition (CONV) was also conducted to be used as a comparison. Surface morphology of the films prepared by EP-SCE were very smooth and compact, and the CONV films were porous. On the other hand, there is not much different in the average grain size between the EP-SCE and CONV films, which was about 50 μm for both the EP-SCE and CONV films. The oxygen content in the EP-SCE films can be up to 28.3 at.% by adjusting the electrodeposition parameters. Micro-pillars with a 20×20 μm2 cross-section and a height at 40 μm were fabricated by focus ion beam from the deposited films. The yield stresses were ranged from 10 to 40 MPa when the current density changed. Acknowledgment: This work was supported by JST CREST Grant Number JPMJCR1433. Reference: [1] Electrochim. Acta 55 (2010) 6469-6475 [2] Thin Solid Films 529 (2013) 25-28 [3] J. Electrochem. Soc. 162 (2015) D423-D426 [4] J. Phys. Chem. C 117 (2013) 25596-25603 [5] Electrochem. Commun. 33 (2013) 68-71 [6] J. Alloys Compd. 403 (2005) 335-340

A growing number of governments are adopting asset-based social policies to assist the poor, but how do such policies spread from one context to another? This article examines the spread of a policy concept – asset building – through analysis of policy diffusion, the process by which ideas that reach one place influence surrounding regions. Specifically, we trace this diffusion in two contexts (Korea and Taiwan) over time. In each case, asset-based research played a role in the development and diffusion of policy. These observations suggest pathways by which policy advocates and scholars can work with policymakers to help shape new asset-based policies.

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.

This study reports structure stability of micro-cantilevers composed of Au-Cu alloy for applications as moveable components in micro-electrical-mechanical system (MEMS) accelerometers. Au-based micro-components are developed to replace conventional Si-based components in a MEMS accelerometer to allow further miniaturization of the device [1]. However, the mechanical strength of Au is relatively low when compared with that of Si. The low mechanical strength raises concerns on structure stability of movable micro-components composed of Au-based materials, which could affect reliability and lifetime of the device. Electroplating is a promising technique in manipulating properties of the metallic materials for applications in MEMS. For instance, grain refinement effect often observed in electroplating can be employed to enhance the mechanical strength by the grain boundary strengthening mechanism [2]. In addition, alloy electroplating is a fascinating technique capable of controlling composition of the metallic material, and alloying the metallic material allows utilization of the solid solution strengthening mechanism to further enhance the mechanical strength [3]. By synergistic effects of the grain boundary strengthening and solid solution strengthening mechanisms, an ultra-high yield stress of 1.15 GPa [3] is reported for electroplated Au-Cu micro-specimens, which is comparable to fracture strength of Si. In order to apply the high-strength Au-Cu alloy as movable structures in MEMS devices, investigating the vibration fatigue is necessary to confirm the reliability and the lifetime. In this study, long-term vibration tests of micro-cantilevers fabricated by combining lithography and Au-Cu alloy electroplating were conducted to reveal effects of the vibration fatigue on structure stability of the Au-Cu alloy micro-cantilevers. Fabrication process of the micro-cantilevers is illustrated in Fig. 1. The Ti barrier layer and the Au seed layer were deposited by sputtering, and the layer thicknesses were both at 100 nm. The Au–Cu electrolyte used in this work was a commercially available electrolyte provided by MATEX Co. Japan, which contained 17.3 g/L of X3Au(SO3)2 (X = Na, K), 1.26 g/L of CuSO4, and ethylenediaminetetraacetic acid as the additive with pH at 7.5. The electroplating was carried out at 50 ◦C, and the current density was varied from 0.1 to 3 mA/cm2. A piece of Pt plate was used as the anode. Image of the Au-Cu alloy micro-cantilevers before the vibration test is shown in Fig. 2. Design-length of the micro-cantilever (l) was varied from 50 ~ 1000 μm, and design-width of the micro-cantilever (w) was ranged from 5 ~ 20 μm. Thickness of the Au-Cu alloy layer (t) was from 2.3 ~ 5.0 μm. The long-term vibration test was carried out under conditions of the cycle number in a range from 103 to 106, the frequency of 10.0 Hz, and the acceleration of 1.0 G (1 G = 9.8 m/s2). The structure stability was determined by evaluating height profiles of top surface of the micro-cantilevers before and after the vibration test by a 3D optical microscope. Height profiles of a micro-cantilever composed of 97.7 % Au with the length at 1000 μm, the width 20 μm, and the thickness at 3.9 μm before and after the vibration test are shown in Fig. 3. Fluctuations in the height before the vibration test, the 0 cycle result, were mainly results of the surface roughness. After 106 cycles of the vibration test, the micro-cantilever was still intact as observed from the optical microscope. The height profiles did not change much after the vibration. In order to quantify the structure stability, deflection at tip of the micro-cantilever was determined. The tip deflection merely changed 0.37 μm for the 1000 μm long micro-cantilever after 106 cycles of the vibration test. This result confirmed high structure stability in the electroplated Au-Cu alloy micro-cantilever and demonstrated the superiority of this Au-Cu alloy structure in applications as movable components in MEMS devices. [1] D. Yamane, T. Konishi, T. Matsushima, K. Machida, H. Toshiyoshi, K. Masu, Appl. Phys. Lett., 104 (2014) 074102. [2] H. Tang, C.-Y. Chen, T. Nagoshi, T.-F.M. Chang, D. Yamane, K. Machida, K. Masu, M. Sone, Electrochem. Commun., 72 (2016) 123–130. [3] H. Tang, C.-Y. Chen, M.Yoshiba, T.Nagoshi, T.-F.M. Chang, D.Yamane, K.Machida, K.Masu, M.Sone, Electrochemical Society, 164 (2017) 244–247 Figure 1

The crystal structures of N-o-hydroxybenzimido-meso-tetraphenylporphyrinatozinc(II) toluene solvate [Zn(N-NCO(o-OH)C6H4-tpp)·C6H5CH3; 4·C6H5CH3], N-o-hydroxybenzimido-meso-tetraphenylporphyrinatonickel(II) chloroform solvate [Ni(N-NCO(o-OH)C6H4-tpp)·0.6CHCl3; 5·0.6 CHCl3], N-o-hydroxybenzimido-meso-tetraphenylporphyrinatocopper(II) toluene solvate [Cu(N-NCO(o-OH)C6H4-tpp)·C6H5CH3; 6·C6H5CH3] and N-o-oxido-benzimido-meso-tetraphenylporphyrinato(-κ4,N1,N2,N3,N5,κO2) manganese (III) methylene chloride·methanol solvate [Mn(N-NCO(o-O)C6H4-tpp)·CH2Cl2·MeOH; 8·CH2Cl2·MeOH] were established. The coordination sphere around Zn2+ ion in 4·C6H5CH3, (or Ni2+ ion in 5·0.6 CHCl3 or Cu2+ ion in 6·C6H5CH3) is a distorted square planar (DSP) whereas for Mn3+ in 8·CH2Cl2·MeOH, it is a distorted trigonal bipyramid (DTBP) with O(1), N(1) and N(3) lying in the equatorial plane for 8·CH2Cl2·MeOH. The g value of 8.27 measured from the parallel polarization of X-band EPR spectra at 293 K is consistent with the high-spin mononuclear manganese(III) (S = 2) in 8. The magnitude of axial (D) zero-field splitting (ZFS) for the mononuclear Mn(III) in 8 was determined approximately as 3.0 cm−1 by the paramagnetic susceptibility measurements and conventional EPR spectroscopy.

In this paper, we present an analytical and experimental study of the pressure barrier developed in an axisymmetric microchannel with sudden expansion working as a capillary valve for regulating liquid flow for microfluidics. The analysis is based on the variation in the free energy of the liquid–solid–gas interfaces with liquid volume. The pressure barrier developed at the meniscus is obtained in a rather simple form valid for both hydrophilic and hydrophobic channel walls. The maximum pressure barrier, termed the burst pressure, for a capillary valve necessary to stop liquid flow is found to be a function of the channel geometry and liquid-channel interfacial properties. The analytical results are confirmed by flow visualization experiments in which the burst pressure and the growth of the meniscus are measured. The measurements were carried out for microchannels made of hydrophilic and hydrophobic materials with different diameters and expansion angles in combination with liquids having different interfacial properties.

The coordinating properties of N - o -chlorobenzamido- meso -tetraphenylporphyrin ( N -NHCO( o -Cl)C 6 H 4 -Htpp; 11 ) have been investigated for the Zn 2+ ion. Insertion of Zn results in the formation of the zinc complex Zn( N -NCO( o -Cl)C 6 H 4 -tpp)(MeOH) · MeOH ( 12 · MeOH). The diamagnetic 12 · MeOH can be transformed into the diamagnetic Zn( N -NHCO( o -Cl)C 6 H 4 -tpp)Cl · CH 2 Cl 2 ( 13 · CH 2 Cl 2 ) in a reaction with aqueous hydrogen chloride (2%). X-ray structures for 12 · MeOH and 13 · CH 2 Cl 2 have been determined. The coordination sphere around the Zn 2+ ion in 12 · MeOH is a distorted trigonal bipyramid with N(2), N(4) and O(2) lying in the equatorial plane, whereas for the Zn 2+ ion in 13 · CH 2 Cl 2 , it is a square-based pyramid in which the apical site is occupied by the Cl(1) atom.

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.