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Simple Summary: The scarce genus of Pelecocera Meigen, 1822 (Diptera: Syrphidae) from the Holarctic Region has 14 species described. The taxonomic diagnosis of the immature stages of Pelecocera has not been performed; however, Pelecocera (Chamaesyrphus) japonica (Shiraki, 1956) larvae were found feeding on Rhizopogon roseolus in Japan. Following the findings in Japan, larvae of Pelecocera were collected in Denmark. We here report the first morphological description of the immature stages of Pelecocera (Chamaesyrphus) lugubris and Pelecocera (Pelecocera) tricincta, as well as specific data on their breeding sites. Larvae of both species were collected feeding on Rhizopogon luteolus in Denmark. The morphology of immature stages of P. lugubris and P. tricincta was studied by using both a scanning electron microscope and a stereomicroscope. A taxonomic diagnosis of the immature stages of Pelecocera and a taxonomic key are provided to separate them from the larvae of other genera. With 14 species, Pelecocera Meigen, 1822 is a scarce and small genus of hoverflies (Diptera: Syrphidae: Rhingiini) from the Holarctic Region. Apart from the finding of larvae of Pelecocera (Chamaesyrphus) japonica (Shiraki, 1956) in fungi in Japan, the larval biology of these hoverflies is virtually unknown. The early stages of all Pelecocera species are undescribed. The adults of Pelecocera (Pelecocera) tricincta Meigen, 1822 and Pelecocera (Chamaesyrphus) lugubris Perris, 1839 are found in Palearctic conifer forests with sand dunes. We here report the first morphological evidence of the immature stages of Pelecocera (P. lugubris and P. tricincta), as well as specific data on their breeding sites. Larvae of both species were collected feeding on the hypogean basidiomycete Rhizopogon luteolus Fr. & Nordholm, 1817 in Denmark in 2021. The first larval stage and second larval stage of P. tricincta, the third larval stage of P. lugubris, the anterior respiratory process, and the posterior respiratory process of the puparia of these two species were analyzed and studied using stereomicroscope and scanning electron microscope techniques. The chaetotaxy of the puparium of each species is also described and illustrated. A taxonomic diagnosis of the larvae of the genus Pelecocera is proposed to separate them from the larvae of other genera of the tribe. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the controlling factor/s of coral growth in the northwest Pacific during the Holocene. Here, we present newly acquired growth data and radiocarbon age dates of fossil Porites corals collected from Holocene uplifted marine terraces in Kikaijima, southern Japan and northwest Luzon, Philippines. Carbonate mineral identification using X-ray diffraction (XRD) and scanning electron microscope (SEM) was conducted to screen for any diagenetic alteration in the fossil corals. We used accelerator mass spectrometer (AMS) - 14C dating to determine the absolute age dates of the fossil corals. Well-preserved fossil corals yielded radiocarbon age dates of 3235 ± 20 and 5712 ± 24 cal. yr BP for Kikaijima and 6285 ± 79, 6144 ± 77, 4336 ± 21, 4277 ± 19, 4200 ± 20, and 2972 ± 70 cal. yr BP for northwest Luzon. X-ray imaging of a 5-mm thick coral slab was utilized to measure growth variables. Linear extension rate, skeletal density, and calcification rate of Kikaijima corals are 3.77-8.72 mm/yr, 1.71-1.87 g/cm3, and 0.70-1.56 g/cm2yr, respectively. Linear extension rate, skeletal density, and calcification rate from northwest Luzon corals are 10.17-17.6 mm/yr, 0.66-1.67 g/cm3, and 0.91-2.81 g/cm2yr, respectively. Average linear extension rate from both sites was significantly and positively related to average calcification rate (r = 0.72, p = 0.019, n = 10). Skeletal density and linear extension rate measured from both sites were inversely related with each other (r = -0.56, p = 0.09, n = 10). Our data suggest that the variations in linear extension rates of fossil corals were influenced by the sea surface temperature (SST) difference between the study sites. However, data from modern corals are still needed to establish the local linear extension rate-SST relationship and to quantitatively evaluate how coral growth changes with respect to SST. Geomorphological, sedimentological, and geochronological studies of Holocene uplifted marine terraces should be conducted to provide the timing of emergence and coral reef development during Holocene. [ABSTRACT FROM AUTHOR]

The epistylidid ciliate Epistylis wuhanensis Wang, Zhou, Guo, and Gu, 2017 was found attached to the body surface of Lernaea cyprinacea Linnaeus, 1758 (Copepoda: Lernaeidae) parasitizing Rhinogobius similis Gill, 1859 (Perciformes: Gobiidae) from the Arida River in Wakayama Prefecture, Japan. This epistylidid was described based on live ciliates, stained specimens, and scanning electron microscope observation with molecular information. This is the first record of E. wuhanensis from Japan and the second record of the epistylidid attached to metazoans. A list of records of Epistylis Ehrenberg, 1830 species attached to metazoans in Japan is proposed. [ABSTRACT FROM AUTHOR]

Thick sediment layers frequently cover the Japan islands' surface, and their frictional properties significantly affect the shallow slip behavior that occurs during earthquakes. However, laboratory data on the properties of the shallow zone remain limited. We collected tuff breccia samples from deep borehole cores in the Miocene "Green Tuff" formation, a major surface cover, and performed velocity-stepping friction tests on these samples under in situ stresses of 2 to 20 MPa to assess the velocity dependence of their frictional strength. The samples exhibit predominantly frictionally stable, velocity-strengthening behavior over the range of normal stresses tested, which supports the hypothesis that shallow sediment layers are seismically quiescent. This result is consistent with the low seismicity and attenuation of coseismic slip occurring in the shallow zone that is observed during regional earthquakes. Microstructural observations of the postmortem samples using optical and scanning electron microscopes indicate a fabric transition from boundary shear localization to distributed cataclastic flow with increasing normal stress. Our laboratory investigation of the depth-variable distribution of the frictional velocity dependence of a shallow sediment layer would provide further insight into the mechanical role for earthquake rupture dynamics and shallow seismicity. [ABSTRACT FROM AUTHOR]

Mineral oil–based liquids are normally used as the dielectric fluid in electrical discharge machining (EDM) where it has the ability in improving the efficiency of the machining process. Nevertheless, these dielectric fluids have the tendency to cause environmental problems. Therefore, as an alternative, gas has been introduced as the dielectric fluid also known as dry EDM (DEDM) process. However, kerf variation in dry micro-wire EDM (DμWEDM) process remains a critical issue. Thus, the objective of this research is to investigate kerf accuracy in DμWEDM. Experimental investigation was carried out on a stainless steel (SS304) with a tungsten wire as the electrode and compressed air as the dielectric fluid using integrated multi-process machine tool, DT 110 (Mikrotools Inc., Singapore). Central composite design (CCD) was used to design the experiment using two controlled parameters: capacitance and gap voltage. Analysis of variance (ANOVA) was used to analyse the results and to evaluate the adequacy of the developed model. The results were obtained by measuring the kerf using a scanning electron microscope (SEM) (JEOL JSM-5600, Japan). The investigation of kerf was divided into two responses which were upper kerf and bottom kerf. Empirical models were developed, and it was found that both parameters (capacitance and gap voltage) have high influence on both responses. The optimum parameters for both minimum upper and bottom kerf were found to be 0.1 nF capacitance and 91 V gap voltage. The developed models were found to be adequate since the percentage error is relatively small (< 3%). [ABSTRACT FROM AUTHOR]

Micro dry wire electrical discharge machining (μDWEDM) is an environmental-friendly machining process where gas is used as the dielectric fluid instead of liquid. In this process, certain modifications of wire electrical discharge machining (WEDM) are required during the machining operation for stable machining. In μDWEDM, the process is considered stable if the machining is continuous without any interruption due to wire breakage or wire lag. However, in the present state of the arts, stable and smooth machining process using μDWEDM remains a critical issue. Hence, the objectives of this research are to establish a stable μDWEDM process using two different experimental approaches: one-factor-at-a-time (OFAT) and design of experiment (DOE) method. The investigation was performed on a stainless steel (SS304) with a tungsten wire as the electrode using integrated multi-process machine tool, DT 110 (Mikrotools Inc., Singapore). Types of dielectric fluid, dielectric fluid pressure, polarity, threshold voltage, wire tension, wire feed rate, wire speed, gap voltage, and capacitance were the controlled parameters. The machining length of the microchannels was measured using scanning electron microscope (SEM) (JEOL JSM-5600, Japan). Analysis based on these two experimental approaches shows that stable μDWEDM process is achievable when the types of dielectric fluid, dielectric fluid pressure, polarity, threshold voltage, wire tension, wire feed rate, and wire speed remain as the fixed parameters while the capacitance and gap voltage remain as the controlled parameters. [ABSTRACT FROM AUTHOR]

• The mass-measurement-type optical particle counting method has been developed. • An accurate determination of the number concentration of liquid-borne particles. • A suspension of 2 μm PSL particles was used for evaluation of the new method. • The validity of the method was examined by another independent microscopic method. • The new method has been used as the national primary standard at NMIJ/AIST, Japan. We have developed a measurement method that enables accurate determination of the number concentration of liquid-borne particles by adopting simultaneous particle counting and mass measurement. The new measurement method consists of an optical particle counter (OPC) for particle counting, an electronic balance for mass measurement, a syringe pump for sampling, and a pulse height analyzer for signal processing. We refer to this method as the mass-measurement-type optical particle counting (M-OPC) method. The M-OPC method facilitates both metrological traceability of the mass of measured suspensions and evaluation of the counting efficiency of OPCs. Using the M-OPC method, we evaluated the measurement accuracy of two different types of OPCs: a light-scattering type and a light-extinction type. The validity of the measurement results obtained with the M-OPC method was examined by comparison with the results of an independent microscopic method using a scanning electron microscope (SEM). The M-OPC method also offers the possibility of calibrating the number concentration of particles in suspensions with diameters from the sub-micrometer to micrometer range by combining multiple OPCs. This method is expected to be used as the national primary standard at the National Metrology Institute of Japan of the National Institute of Advanced Industrial Science and Technology. [ABSTRACT FROM AUTHOR]

For an SF6 circuit breaker in capacitor bank‐making operation, the inrush current may cause serious erosion to its arcing contacts. In order to observe the characteristics of this erosion, an arc extinguish chamber of SF6 circuit breaker with Cu–W arcing contacts was designed, and experiments of capacitor bank making were carried out. The prebreakdown arcing duration and inrush current were measured, and the mass loss of the contact after 100 times of operation was calculated. Power–frequency‐withstanding voltage was measured after every 20 operations. The surface status, scanning electron microscope (SEM), and energy dispersive x‐ray spectroscopy (EDS) of the contact material were recorded. The characteristics and mechanism of arcing contact erosion in SF6 circuit breaker in the making process were then analyzed. Compared to the case of breaking high current, this analysis found two major mechanisms that lead to severe arcing contact erosion in the case of capacitor bank making operation, namely, the arc erosion due to prebreakdown current and the erosion of arc heated contact due to friction. The erosion after contact caused by mechanical friction occupies a relatively larger proportion in the mass loss of contact materials. Under the conditions of 3 m/s making velocity, 18 kA current peak, and less than 2 ms arcing duration, the mechanical wear mass loss rate is greater than 1.0 mg/C. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Anti-rapakivi feldspar phenocrysts of ternary Or–Ab–An compositions in a sheet trachyte from Utagi Pass, Oki-Dogo Island (Sea of Japan), show characteristic lamellar–wavy textures, commonly also with patchy texture. These textures have scales ranging from micrometers to decamicrometers, show narrow variation in composition, and preserve very fine cryptoperthites with high-temperature structural states. Several types of fluorite alignment are developed in the lamellar–wavy–patchy textures. Small fluorite grains (mostly <100 nm in size) are not distributed homogeneously or randomly but are heterogeneously or locally dispersed/clustered. Complex microtextures and alignment of fluorites in groundmass feldspars are also observed. In addition to these occurrences of fluorite, interstitial fluorite is found in the groundmass. Feldspars were examined using an electron microprobe analyzer, a scanning electron microscope, a transmission electron microscope, cathodoluminescence imager spectrometers and a Fourier transform-infrared spectrometer. It is inferred from the obtained data that the feldspar microtextures are products of complex, kinetically controlled magmatic crystallization with predominantly diffusion-controlled resorption reactions under H 2 O-poor or near-anhydrous conditions, and they are developed in association with the crystallization of groundmass during magma ascent to final emplacement. In addition, fluorite alignments in the phenocrysts and groundmass feldspars are estimated to have formed by diffusion-controlled replacement through interaction with residual melt during magma ascent. The interstitial fluorite was the final crystallization product of the residual melt. These various occurrences of fluorite constitute a valuable record of the behavior of F in natural volcanic systems. • Complicated lamellar-wavy-patchy texture in phenocryst feldspars formed by magmatic replacement reactions in a trachyte. • Feldspar microtextures and compositional variations record the changes of magma conditions during ascent. • Fluorite alignments in phenocryst and groundmass feldspars, and interstitial fluorite in groundmass. • Various occurrences of fluorite recording of the behaviors of fluorine in alkaline volcanic rocks. [ABSTRACT FROM AUTHOR]

Segmentation and analysis of individual pores and grains of mudrocks from scanning electron microscope images is non-trivial because of imaging artifacts, variation in pixel grayscale values across images, and overlaps in grayscale values among different physical features such as silt grains, clay grains and pores, which make identifications difficult. Moreover, because grains and pores often have overlapping grayscale values, direct application of threshold-based segmentation techniques is not sufficient. Recent advances in the field of computer vision have made it easier and faster to segment images and identify multiple occurrences of such features in an image, provided that ground-truth data for training the algorithm are available. Here we propose a deep learning SEM image segmentation model, MudrockNet based on Google's DeepLab-v3+ architecture implemented with the TensorFlow library. The ground-truth data were obtained from an image-processing workflow applied to scanning electron microscope images of uncemented muds from the Kumano Basin offshore Japan at depths <1.1 km. The trained deep learning model obtained a pixel-accuracy > 90%, and predictions for the test data obtained a mean intersection over union (IoU) of 0.6663 for silt grains, 0.7797 for clay grains and 0.6751 for pores. We also compared our model with the random forest classifier using trainable Weka segmentation in ImageJ, and it was observed that MudrockNet gave better predictions for silt grains, clay grains and pores in most cases. The size, concentration, and spatial arrangement of the silt and clay grains can affect the petrophysical properties of a mudrock, and an automated method to accurately identify the different grains and pores in mudrocks can help improve reservoir and seal characterization for petroleum exploration and anthropogenic waste sequestration. • MudrockNet allows automated identification of pores and silt in mudrock SEM images. • Model obtained 0.6663(silt), 0.7797(clay) and 0.6751(pores) mean intersection over union on test set. • MudrockNet achieved superior segmentation results than trainable Weka in ImageJ. [ABSTRACT FROM AUTHOR]

• A new toxic dinoflagellate Fukuyoa koreansis was described from Korean coastal waters. • Based on the height-to-width (H/W) and depth-to- width ratios in cell size, the apical pore H/W ratio and thecal pore size, Fukuyoa koreansis could be distinguished from other Fukuoya species. • The phylogenetic position of Fukuyoa koreansis was grouped with F. cf. yasumotoi isolated from Japan and clearly divergent from other Fukuyoa species. • The required temperatures and salinities for growth distinguished Fukuyoa koreansis from Gambierdiscus species. To clarify an unspecified toxic Gambierdiscus- like species isolated from seawaters off Jeju Island, Korea, its morphology and molecular phylogeny based on the small subunit (SSU) and partial large subunit (LSU) rRNA gene sequences were examined. Cells were narrow in ventral view and broad in lateral view with a smooth surface. The round thecal pores were evenly distributed, with an average diameter of 0.41 µm. Cell depth, width and height were 51.7 ± 4.5 μm, 43.0 ± 4.2 μm and 55.0 ± 4.7 μm, respectively, and depth-to-width (D/W) and height-to-width (H/W) ratios were 1.1 ± 0.2 μm and 1.3 ± 0.02 μm, respectively. The nucleus was located in the hypotheca. Scanning electron microscope observations revealed that the cells displayed a plate formula of Po, 4′, 6′′, 6c, 6s, 5′′′ and 2′′′, and transmission electron microscope observation demonstrated that the cells contained crystal-like particles. Morphological features indicated that the unspecified Korean isolate belonged to the genus Fukuyoa , and based on the H/W and D/W ratios, the apical pore H/W ratio and thecal pore size, it could be differentiated from other Fukuyoa species. The phylogenetic analyses based on the SSU and LSU rRNA sequences revealed that the Korean isolate was nested within the genus Fukuyoa with high support, and it grouped with F. cf. yasumotoi isolated from Japan. Based on the morpho-molecular data, a new species, Fukuyoa koreansis sp. nov. is proposed. The maximum growth rate (0.254 d−1) of F. koreansis was observed at 25°C and a salinity of 25. The required levels of temperature and salinity for growth distinguished Fukuyoa koreansis from Gambierdiscus species. [ABSTRACT FROM AUTHOR]

A new species of the genus Polycopetta Chavtur, 1981, Polycopetta quadrispinata sp. n. is described from the interstitial environment of Mihomasaki Beach in Japan. These observations showed some morphological peculiarities of Polycopetta quadrispinata sp. n. compared with its congeners; P. monneroni Chavtur, 1979, P. curva Chavtur, 1979, P. bransfieldensis (Hartmann, 1987), and P. pax Kornicker and Harrison- Nelson, 2005. Three characteristics are described for the first time: (1) a seta with serrated tip on the male antennula, (2) the endopodite of the fifth limb consisting of two podomeres, (3) the long spermatozoa in the male posterior body. More detailed observations of the type species are needed in order to update the generic diagnosis. [ABSTRACT FROM AUTHOR]

This study aims to quantify nitrogen (N) effect on occurrence of perfect rice kernel (PRK) and imperfect grains which includes white-belly rice kernel (WBRK), white-core rice kernel (WCRK), green rice kernel (GRK), opaque rice kernel (ORK), and other imperfect grains (OTHERS). Two-year field experiments involving six japonica rice cultivars and seven N treatments were performed. The structural differences between white-belly and white-core tissues were compared using scanning electron microscope. Averaged over cultivars, grain yield increased progressively with N rate. PRK increased with N rate in 2008, but decreased with increased N rate in 2009. WBRK and WCRK decreased as N rate increased for both years. High N input resulted in higher occurrence of GRK and OTHERS for both years. Most starch granules in white-belly tissues are intact and surrounded by globular protein bodies, with many air spaces between them; while in white-core tissues, starch granules are easily broken into many single granules and no protein bodies are visible. Our results suggest that N has suppressing influence on chalky grains but favorable effect on other imperfect grains, and indicate different mechanism between WBRK and WCRK. [ABSTRACT FROM AUTHOR]

Abstract  In this paper we report fabrication of high-aspect-ratio micro-structure of Ni by electroplating, using a micro-machining technique of resists using proton beam writing (PBW) at Japan Atomic Energy Agency (JAEA). A micro-structure of 5 μm thick PMMA was fabricated by exposure using PBW at 1.7 MeV and by development. A Ni structure was then formed by electroplating on the micro-structure of PMMA. Vertical and smooth side walls observed by a scanning electron microscope (SEM) indicate that PBW can be a versatile tool for fabrication of resists and metal microstructure in combination with electroplating. The electroplated Ni structure can be used as a resolution standard, which enabled us to focus the proton beam down to 130 nm. [ABSTRACT FROM AUTHOR]

Total suspended particulate (TSP) samples were collected from three areas (commercial, residential and agricultural) in and near Akita City in northern Japan, October 1996 (rice straw burning period), over three days with a one-hour sampling interval for each area. The elemental composition and particle shape of TSP samples were determined and/or observed by PIXE and a Scanning Electron Microscope (SEM) combined with Energy Dispersive X-ray (EDX) analysis. In the hourly TSP samples collected during the rice straw burning period, values of 24 elements were determined for each area, and Na, Mg, Al, Si, S, K, Ca and Fe were the major components. Comparing the arithmetic means of elemental concentrations in TSP for the rice straw burning and non-snow-clad period (May – June 1996), in the residential and agricultural areas the Si concentration in the rice straw burning period was approximately two times that in the non-snow-clad period, and K and Ca concentrations in the rice straw burning period were a little higher than those in the non-snow-clad period. In the residential and agricultural areas, change in SPM concentration and change in Si, K and Ca concentrations were in relative agreement during the hours that smoke from rice straw burning was present in the atmospheric space. With the aid of SEM- EDX analysis, many cubic particles were observed for almost all hourly TSP samples. The cubic particles were of the silicon-rich type, and their morphology was rice straw fragments or aggregation of fragments. [ABSTRACT FROM AUTHOR]

Investigation of plant morphological features, pollen, and habitat have been made for two shrub species from Barrow, Alaska, namely Dryas integrifolia M. Vahl and Salix rotundifolia Trautv., both of which are endemic to the Arctic floristic area. The former species has small lanceolate or plate leaves, whereas the latter has rounded leaves with distinct veins, rich in vitamin C. Both have dwarf and sprawling habits. Pollen studies showed that the pollen grains of the two species are spheroidal to sub-spheroidal or prolate. The type of aperture was tricolporate; pollen size 26.3–31.3 μm; ornamentation finely reticulate under a light microscope (LM) and striate-reticulate under a scanning electron microscope (SEM) for D. integrafolia and finely reticulate under the LM and SEM for S. rotundifolia. Comparisons were made between the pollen from the same species from Arctic collections with those from China and Japan. Investigation of pollen morphology of tundra plants can provide significant data for comparative studies of fossil pollen and for the reconstruction of paleovegetation and paleoclimate in the Barrow area. (Managing editor: Ya-Qin Han) [ABSTRACT FROM AUTHOR]

The distribution of Aspergillus flavus and Aspergillus parasiticus in sugarcane field soils and on harvested sugarcane stems was studied on seven islands of Okinawa and Kagoshima Prefectures, the southernmost prefectures in Japan. With the use of a combination of dilution plate and plant debris plate techniques, the fungi were detected on all seven islands studied and in 74% of 53 soil samples. The fungi were also found on the cut surfaces of sugarcane stems from one of the islands. A. parasiticus was the predominant fungus, although many atypical A. parasiticus isolates that produced metulated conidial heads were also obtained. The proportions of isolates testing positive for aflatoxin production were ca. 89% (146 of 164) of all isolates and ca. 69% of A. flavus isolates. More than 40% of A. flavus isolates also produced G aflatoxins. Scanning electron microscopic observation of conidial wall texture was useful in distinguishing A. parasiticus from A. flavus. Cyclopiazonic acid, an indole mycotoxin, was never synthesized by any of the A. parasiticus or G aflatoxin-producing A. flavus isolates tested. [ABSTRACT FROM AUTHOR]

Reports on the collection of total suspended particulate (TSP) samples from commercial, residential and agricultural areas in and near Akita City in northern Japan, from May to June 1996 and January to February 1997 over three days. Determination of elemental composition and particle shape of TSP samples and observation by Particle-induced X-ray Emission and a scanning electron microscope combined with Energy Dispersive X-ray analysis; Number of elements found in snow-clad period samples.

Characterizes the total suspended particulate (TSP) along a highway in Akita City, Japan by elemental components, temporal variation of elemental concentration and particle shape of the TSP. Use of proton-induced x-ray emission and a scanning electron microscope combined with energy dispersive x-ray analysis; Distinction between snow-clad period and non-snow-clad period.

Focuses on the Miocene intra-arc bending at an arc--arc collision zone in central Japan. Reconstruction of the Philippine Sea Plate motion; Use of scanning electron microscope studies; Migration of the Subducted Izu-Bonin Ridge volcanic arc.

The article reports on a study of estimating the daily age of adult Japanese anchovy called Engraulis japonicus in Honshu, Japan through otolith daily microincrements. It examined otoliths at 200x magnification under a light microscope through scanning electron microscope (SEM). It counted increments from nucleus to posterior margin. It founds out that fish from Sanriku grew to about 115 mm for approximately eight months. It also suggested that faster growth is a trait of offshore anchovy rather than those of inshore anchovy.

Abstract: We have developed a positron microbeam using magnetic lenses based on the commercial scanning electron microscope (SEM). A slow positron beam was generated using a handmade source with 22Na and a solid neon moderator. The beam diameter was 3.9μm on a target. Two-dimensional image of S parameter was successfully obtained. By introducing a beam pulsing section, positron lifetime measurement beam is also available. [Copyright &y& Elsevier]

Aluminum-phosphate-sulfates (APS) of the alunite supergroup occur in igneous rocks within zones of advanced argillic and silicic alteration in porphyry and epithermal ore environments. In this study we report on the presence of woodhouseite-rich APS in ash from the 27 September 2014 hydrothermal eruption of Ontake volcano. Scanning electron microscope coupled with energy dispersive X-ray spectrometer (SEM-EDS) and field emission (FE)-SEM-EDS observations show two types of occurrence of woodhouseite: (a) as cores within chemically zoned alunite-APS crystals (Zoned-alunite-woodhouseite-APS), and (b) as a coherent single-phase mineral in micro-veinlets intergrown with similar micro-veinlets of silica minerals (Micro-wormy-vein woodhouseite-APS). The genetic environment of APS minerals at Ontake volcano is that of a highly acidic hydrothermal system existing beneath the volcano summit, formed by condensation in magmatic steam and/or ground waters of sulfur-rich magmatic volatiles exsolved from the magma chamber beneath Mt. Ontake. Under these conditions, an advanced argillic alteration assemblage forms, which is composed of silica, pyrophyllite, alunite and kaolinite/dickite, plus APS, among other minerals. The discovery of woodhouseite in the volcanic ash of the Ontake 2014 hydrothermal eruption represents the first reported presence of APS within an active volcano. Other volcanoes in Japan and elsewhere with similar phreatic eruptions ejecting altered ash fragments will likely contain APS minerals derived from magmatic-hydrothermal systems within the subvolcanic environment. The presence of APS minerals within the advanced argillic zone below the summit vent of Ontake volcano, together with the prior documentation of phyllic and potassically altered ash fragments, provides evidence for the existence within an active volcano in Japan of an alteration column comparable to that of porphyry copper systems globally. [ABSTRACT FROM AUTHOR]

Reports on the development of a scanning electron microcope by researchers from Horiba Ltd., Ulvac Inc., and Tokyo University in Japan. Features of the proof-of concept prototype; Use of a ceramic column with integrated electrostatic lenses made by MEMS technology; Provision of precision processing and assembly necessary to make the smaller and more effective electrostatic lenses.