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We developed a new front-end application-specific integrated circuit (ASIC) to upgrade the Maia X-ray microprobe. The ASIC instruments 32 configurable channels that perform either positive or negative charge amplification, pulse shaping, peak amplitude, and time extraction along with buffered analog storage. At a gain of 3.6 V/fC, 1- $\mu \text{s}$ peaking time, and a temperature of 248 K, an electronic resolution of 13 and 10 $e^{-}$ rms was measured with and without a silicon drift detector (SDD) sensor, respectively. A spectral resolution of 170-eV full-width at half-maximum (FWHM) at 5.9 keV was obtained with an 55Fe source. The channel linearity was better than ± 1 % with rate capabilities up to 40 kcps. The ASIC was fabricated in a commercial 250-nm process with a footprint of 6.3 mm $\times $ 3.9 mm and dissipates 167 mW of static power.

Electrolytic ablation (EA) is a promising nonthermal tumor ablation technique that destroys malignant cells through induction of a locoregional pH change. EA is typically performed by inserting needle electrodes inside the tumor followed by application of direct current (DC), thus inducing electrolysis and creating localized pH changes around the electrodes. In this paper, we report an ultrasonically powered implantable EA microprobe that may increase the clinical relevance of EA by allowing wireless control over device operation (capability to remotely turn the device on and off) and providing flexibility in treatment options (easier to administer fractionated doses over a longer period). The wireless EA microprobe consists of a millimeter-sized piezoelectric ultrasonic receiver, a rectifier circuit, and a pair of platinum electrodes (overall size is 9 × 3 × 2 mm3). Once implanted through a minimally invasive procedure, the microprobe can stay within a solid tumor and be repeatedly used as needed. Ultrasonic power allows for efficient power delivery to mm-scale devices implanted deep within soft tissues of the body. The microprobe is capable of producing a direct current of 90 µA at a voltage of 5 V across the electrodes under low-intensity ultrasound (~200 mW/cm2). The DC power creates acidic (pH 12.9) regions around the anode and the cathode, respectively. The pH change, measured using tissue-mimicking agarose gel, extends to 0.8 cm3 in volume within an hour at an expansion rate of 0.5 mm3/min. The microprobe-mediated EA ablative capability is demonstrated in vitro in cancer cells and ex vivo in mouse liver.

The new Sumy nuclear microprobe for high resolution applications has the same beam line with the present microprobe and uses the same object and aperture collimators. The new probe-forming system is based on five magnetic quadrupole lenses of integrated design with four independent power supplies. It consists of quadrupole doublet of the present microprobe and quadrupole triplet which is allocated after the target chamber of the present microprobe. The electrostatic scanning system of a dog-leg type is located before the triplet. The new target chamber of rectangular design has an optical microscope, secondary electron detector, charged particle detector, target stage and possibility to equip additional devices. Such configuration allows one to install two microprobes for different applications at one beam line, that significantly reduces the cost of the new facility. The present paper describes the status of the new Sumy microprobe, its beam optics and design.

The new generation of solar cells aims to overcome many of the issues created by silicon-based devices (e.g., decommissioning, flexibility and high-energy production costs). Due to the scarcity of the resources involved in the process and the need for the reduction of potential pollution, a greener approach to solar cell material production is required. Among others, the solvothermal approach for the synthesis of nanocrystalline Cu–Sn–S (CTS) materials fulfils all of these requirements. The material constraints must be considered, not only for the final product, but for the whole production process. Most works reporting the successful synthesis of CTS have employed surfactants, high pressure or noxious solvents. In this paper, we demonstrate the synthesis of nanocrystalline kuramite by means of a simpler, greener and scalable solvothermal synthesis. We exploited a multianalytical characterization approach (X-ray diffraction, extended X-ray absorption fine structure, field emission scanning electron microscopy, Raman spectroscopy and electronic microprobe analysis (EMPA)) to discriminate kuramite from other closely related polymorphs. Moreover, we confirmed the presence of structural defects due to a relevant antisite population.

This paper presents the fabrication and measurements of a vertical out-of-plane microprobe electrode array with individual interconnects through the substrate using a silicon through-glass via (TGV) with transparent properties. The TGV was fabricated using a low-resistance silicon (LRS) via and the glass reflow process. The microprobe structure was formed by multiple deep reactive ion etching and reactive ion etching processes using one-step photolithography and a single etch mask. The height and pitch of the microprobe are designed to be 90 μm and 210 μm, respectively. Cr and Au conductive layers were deposited and patterned on the silicon microprobe structure. A parylene-C thin film was used as an insulating layer and it was etched only at the tip-end through the self-alignment fabrication process using a thick photoresist to expose the conductive part. Each microprobe electrode was independently connected to the backside of the substrate through the silicon TGV. The single via resistance was measured to be 1.26 ± 0.041 Ω. To verify the electrochemical characteristics of the microprobe electrodes with individual interconnects, the steady-state limiting current through the redox reaction was measured by the cyclic voltammetry method for each electrode. The measured steady-state peak current of the microprobe electrode was compared with the theoretical calculation. Further, the electrode impedance was measured and the equivalent circuit analysis was constructed using the Zview impedance modeling software. Experiments were conducted to measure the impedance of 16 microprobe electrodes, and it was confirmed that the impedance did not exceed 1 MΩ at 1 kHz. Then, primary rat cortical neuron cells (DIV 7) were cultured on the fabricated microprobe electrodes and neural spike signals were successfully measured. Also, the light transmittance experiment was conducted to measure the transparency of the TGV structure fabricated through the glass reflow process.

In Harbin, the 300 MeV proton microprobe system with long-length quadrupole lenses, as a component of the Space Environment Simulation Research Infrastructure (SESRI), is under development driven by many applications in space science and proton therapy. Significant challenges have previously been addressed including minimization of ion scattering from collimators and the development of promising focusing systems compatible with the large beam magnetic rigidity. Here the intrinsic aberrations contributed by the fringe field regions of quadrupole lenses in the probe forming lens system are investigated with respect to the model used for the fringe field profile. The investigation compares the rectangular model, commonly used with the matrix method, and a more sophisticated model employing a multiphysics code for the full field profile used with a numerical raytracing method. For computational and constructional efficiency the proposed triplet system of long-length quadruple lenses required to achieve strong focusing was split into three pairs of two identical short quadrupole lenses, forming a sextuplet microprobe system. The comparison of the two fringe field models show large variations in the aberration coefficients of this system, however the rectangular model is suitable for a broad survey of possible systems to identify promising configurations for further optimization.

Collection of variously colored gem quality iron-bearing beryl from two Brazilian deposits, Lavra do Abilio (Minas Gerais) and Garimpo do Cercadinho (Bahia) was studied by polarized optical absorption microspectroscopy and microprobe analysis. The main attention was paid to spatial distribution of Fe2+ in tetrahedral structural site of Be2+, estimated by intensity of E⊥c-polarized electronic spin-allowed band of BeFe2+ at ~ 12,000 cm−1, mainly along c-axis of the crystals. It is found that in the samples from the two deposits these characteristics are different: in beryl from Lavra do Abilio the distribution is nearly homogeneous, while in those from Garimpo do Cercadinho BeFe2+-content strongly varies along the crystal’s elongation that may indicate the different physico-chemical conditions of crystallization. It is found that there is no correlation between distribution of BeFe2+, Fetotal, detected by microprobe, and Fe2+ in octahedral Al-site, which causes blue color of aquamarine and green—of “green” beryl, wherein heliodor centers are also involved in process of coloration. Judging from intensity of weak narrow spin-forbidden bands of octahedral Fe3+ in Al-sites and narrow near-infrared lines of vibration transition of H2O-molecules in the structural channels, these two admixtures are distributed homogenously in beryl from both deposits. A light-blue synthetic hydrothermal beryl was also studied for comparison. It is found that BeFe2+-distribution along and across elongation of the sample is essentially homogeneous.

Mineral assemblages, the peculiarities of intergrowths, chemical composition, and Sb and As distribution in coexisting fahlore and bournonite-seligmannite solid solutions of the Darasun gold deposit are studied. The almost complete solid solution between bournonite and seligmannite with continuous Sb–As isomorphism for Sb/(Sb + As) ratios from 0.21 to 1.00 is identified for the first time for the Darasun deposit using a microprobe. The composition of fahlore coexisting with bournonite widely varies: Sb/(Sb + As) ratio 0.03–0.96 and Fe/(Fe + Zn) ratio 0.36–0.87. The mutual compositional evolution from early Sb to late As coexisting solid solutions is identified. Based on the Sb and As distribution between coexisting fahlore and bournonite-seligmannite, the temperatures of their joint crystallization are estimated, as well as those of the productive stage, where they are associated with native gold and tellurides (90–335°C).

The main objectives of this study were: 1. to control the efficiency of the application of marble polishing sludge as the main component (35–50 wt%) to neutralize hazardous municipal water treatment sludge (25–50 wt%) for the production of environmentally clean materials that match the mechanical properties required by the standard; lime production waste (10–30%) was used as bonding material; 2. to study the processes of the raw materials chemical interaction and new materials structure formation. The axial strength values of the developed material diverged among 4.02 MPa on the 3rd day, 5.98 MPa on the 28th day and 16.48 MPa on the 365th day. It was determined by the complementary X-ray fluorescence (XRF), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Laser Microprobe Mass Analyzer (LAMMA) and Atomic absorption spectroscopy (AAS) methods that the high strength of the materials from just industrial wastes was explained by the chemical interaction of the components in a highly alkaline aqueous medium with the synthesis of mainly amorphous sol-gel new formations. The results of leaching and solubility tests exhibited a very low level of no bonded metals compared to the current Brazilian sanitarian standards. This provides a potential to significantly reduce the environmental impact by recycling such industrial wastes. In addition, fewer waste dumps reduce the irreversible destruction of natural links by the quarrying of traditional natural building materials.

Inclusions of calcite within large euhedral apatite crystals from the pyroxenite-carbonatite-syenite complex of Sevattur, Tamil Nadu, south India, were identified to represent inclusions of a primary carbonatitic melt (calcite I) from which the apatites have crystallized. The apatites themselves are embedded into a younger batch of calcite-carbonatitic melt (calcite II). Using the synchrotron XRF microprobe at beamline L at HASYLAB/DESY (Hamburg), the concentrations of the trace elements Ba, Sr, Y, Zr, Th, La, Ce, Nd, Sm, Gd, Dy, and Er were determined both in melt inclusions as well as in host apatites and younger carbonatite matrix. Unexpected high REE concentrations were found not only in apatite but also in calcite, especially of the younger matrix phase, in agreement with the whole rock geochemistry. The data reveal an equilibrium distribution between melt inclusions and host apatite that allows the calculation of partition coefficients D = CiAp/CiCc=melt for elements of interest. Assuming 9% crystallization of the melt, which can be calculated from the whole rock analyses, the composition of the primary carbonatite melt prior to apatite crystallization can be determined. This composition is, with the exception of only few elements, nearly equal to that of the younger matrix carbonatite melt (calcite II), and thus gives evidence for the existence of different pulses of carbonatite melt during crystallization and consolidation of the carbonatite body. The results allow new insights into the processes of trace element and REE distribution between the two major igneous components of carbonatites and thus into the question of carbonatitic fractionation processes. The data reveal that mere apatite crystallization and fractionation does not lead to enriched REE compositions during carbonatite evolution but lowers their concentrations in the residual melts. But alternatively, if segregated apatite is collected and incorporated by a new melt batch, the overall REE of this melt will be increased.

Because of their robustness against resetting, in situ U-Pb ages of zircons in lunar impactites have the potential to provide constraints on the lunar bombardment history that may complement the more common K-Ar ages. Most previous work has focused on relatively large zircons that show growth zoning and ages were mostly interpreted as early igneous crystallization ages. Here we combine high-resolution mineralogical imaging and in situ U-Pb dating by ion microprobe to identify, characterize and date

THz-radiation based measurements in reflection-mode provide several advantages over transmission-mode configurations such as depth information and single side sample access useful e.g. for the inspection of multi-layer structures, detection of buried defects or the investigation of samples on THz opaque substrates. We present here an InGaAs:Rh-based photoconductive near-field transceiver probe operating at 1550 nm excitation wavelength which can be directly driven by modern fiber-based THz TDS systems without requiring optical frequency-doubling units. The new probe will foster the configuration of fiber-based robotic scanning systems thanks to the simplification of the optical front-end module.

Snowpack exhibits properties that make it a unique natural archive of airborne pollution. The data on insoluble particles in the Ob River catchment (Western Siberia) snowpack are limited. Insoluble particles in the snowpack of Western Siberia were studied at 36 sites on a 2800 km submeridional profile from the city of Barnaul to Salekhard in February 2020. Snow samples were collected over the full depth of the snow core, from the surface of the snow cover to the boundary with soil, except for the lower 1&ndash, 2 cm. After the filtration of melted snow through a 0.45-&micro, m membrane, the particle composition was studied using a scanning electron microscope with an energy microprobe. In the background areas, the concentration of insoluble particles in the snow was below 2 mg/L. Significantly higher particle concentrations were encountered near cities and hydrocarbon production areas. Particulate matter in snow mainly consists of biogenic and lithogenic particles mixed with anthropogenic particles (ash and black carbon aggregates). The proportion of anthropogenic particles increases near cities and areas of active hydrocarbon production.

In the author’s group, quantum wells were tried in surface emitting lasers around 1986, but we did not achieve low thresholds at that time. Jack Jewell and colleagues made low-threshold surface emitting lasers in 1989. This group aimed at the realization of an optical computer and considered the light source of parallel processing. Among the small posts several mm in diameter, as shown in Fig. 9.1, a quantum well sandwiched between semiconductor DBRs is used as an active layer. In the experiment, current is supplied from above by the microprobe, and light is emitted from the top surface of the post. With this structure, room-temperature continuous operation was also achieved.

Common physical attacks in integrated circuits make use of microprobes to sense information in specific bus lines. It can be mitigated with additional built-in circuitry to detect deviations in the expected capacitance of the bus lines caused by these attacking probes. The strategy is to convert capacitance deviations into delay deviations, followed by time-to-digital conversion to provide a signature that is used to identify a probe attack. However, the sensitivity to delay deviation is highly related to individual sizes of elements that compose the protecting circuit. In this paper, a multi-objective optimization-based methodology is applied to optimize the required silicon area as well as the robustness and parametric manufacturing yield of a microprobe detector. We present the required computational modeling of the circuit optimization objectives and constraints for a successful application of optimization methods. Results show that this approach reduces the required circuit gate area up to 50% compared to manual sizing, while guaranteeing high manufacturing yield.

Besides conventional scanning X-ray fluorescence imaging at synchrotron sources, full-field X-ray fluorescence (FF-XRF) imaging techniques that do not implicitly require spatial scanning of the sample have become available. FF-XRF has become achievable thanks to the development of a new type of energy dispersive CCD-based 2D detector, also referred to as a ‘color X-ray camera (CXC)’ or ‘SLcam’. We report on different imaging schemes for biological samples using FF-XRF imaging: (a) 2D ‘zoom’ imaging with pinhole optics using the ‘camera obscura’ principle; (b) 2D ‘fixed magnification’ imaging using magnifying polycapillary optics; and (c) 3D-FF-XRF imaging using an X-ray sheet beam or computed tomography (CT). The different FF-XRF imaging modes are illustrated using the crustacean Daphnia magna, a model organism for investigating the effects of metals on organism/ecosystem health, and foraminifera, a class of amoeboid protist. Detailed analytical characterization of the set-up is performed through analyzing various reference materials in order to determine limits of detection (LODs) and sensitivities. Experiments were performed using the BAMline at the BESSY synchrotron (Berlin, Germany) and using the P06 Hard X-ray Microprobe at the PETRAIII synchrotron (Hamburg, Germany).

Tokamak plasma facing components have surface roughness that can cause microscopic spatial variations in erosion and deposition and hence influence material migration, erosion lifetime, dust and tritium accumulation, and plasma contamination. However, high spatial resolution measurements of deposition on a sub-µm scale of surface roughness have been lacking to date. We will present elemental images of graphite samples from NSTX-U and DIII-D DiMES experiments performed with a Scanning Auger Microprobe at sub-micron resolution that show strong microscopic variations in deposition and correlate this with 3D topographical maps of surface irregularities. The NSTX-U samples were boronized and exposed to deuterium plasmas. The DiMES samples had localized Al and W films and were exposed to dedicated helium plasmas. Topographical maps of the samples were performed with a 3D confocal optical microscope and compared to the elemental deposition pattern. The results revealed localized deposition concentrated in areas shadowed from the ion flux, incident in a direction calculated by taking account of the magnetic sheath. Keywords: Erosion, Deposition, NSTX-U, DiMES, Plasma-materials interaction, Surface analysis

The methods and results of electron microscopic study of the microstructure of siliceous-carbonate rocks of the domanikoid type are shown. For this purpose, both standard methods for studying the surface of sample chips and a polished surface for microprobe studies and a specially developed method for cathode luminescence study of the pore space are used. Regularities in the catagenetic transformation of Domanik deposits are studied at the microscopic level by electron microscopy. The performed studies show that subcapillary porosity in them is formed only in fractal-cluster areas of origin of secondary (authigenic and syngenetic) carbonatization. This study substantiates the fractal-cluster approach to the probabilistic forecasting of areas of secondary carbonatization and oil-saturated pore volumes.

Objectives Terahertz (THz)‐based imaging techniques hold great potential for biological and biomedical applications, which nevertheless are hampered by the low spatial resolution of conventional THz imaging systems. In this work, we report a high‐performance photoconductive antenna microprobe‐based near‐field THz time‐domain spectroscopy scanning microscope. Materials and methods A single watermelon pulp cell was prepared on a clean quartz slide and covered by a thin polyethylene film. The high performance near‐field THz microscope was developed based on a coherent THz time‐domain spectroscopy system coupled with a photoconductive antenna microprobe. The sample was imaged in transmission mode. Results We demonstrate the direct imaging of the morphology of single watermelon pulp cells in the natural dehydration process with our near‐field THz microscope. Conclusions Given the label‐free and non‐destructive nature of THz detection techniques, our near‐field microscopy‐based single‐cell imaging approach sheds new light on studying biological samples with THz.

The chemical microenvironment surrounding dental composites plays a crucial role in controlling the bacteria grown on these specialized surfaces. In this study, we report a scanning electrochemical microscopy (SECM)–based analytic technique to design and optimize metal ion-releasing bioactive glass (BAG) composites, which showed a significant reduction in biofilm growth. SECM allows positioning of the probe without touching the substrate while mapping the chemical parameters in 3-dimensional space above the substrate. Using SECM and a solid-state H+ and Ca2+ ion-selective microprobe, we determined that the local Ca2+ concentration released by different composites was 10 to 224 µM for a BAG particle size of 2+ was determined to be maximal for particles 7 µm3 for BAG-resin composites and (1.29 ± 0.53) × 107 µm3 for resin-only composites. This study thus lays the foundation for a new analytic technique for designing dental composites that are based on the chemical microenvironment created by biomaterials to which bacteria have been exposed.

A method for studying internal phase inhomogeneities in transparent optical materials by point-to-point three-dimensional laser heterodyne microprobing is proposed. The light microprobe in this case is a traveling micrograting formed in the zone of overlapping of two focused coherent light beams: reference and signal. The size of the microprobe in the x, y, z directions and the degree of influence of spherical aberration with a change in the microprobing depth are estimated. The capabilities of the method are illustrated by examples of detection and subsequent imaging of phase inhomogeneities in the volume of laser ceramics and its random layers.

An optical fiber interferometric microprobe for detection of specific proteins is presented in this paper. The microprobe is an all-fiber device, which is based on Michelson interferometer configuration, which allows for detection of protein antigens in an analyzed solution thanks to antibodies immobilized on the sensor surface. The interferometer is made of dual core fiber and has a precisely formed arm length difference, achieved by splicing a fragment of polarization maintaining fiber to one of the cores. An all-fiber configuration of the sensor decreases substantially cross-sensitivities to temperature and deformation in comparison to other optical fiber interferometers. Reported sensor has a sensing region on the tip of the interferometer and therefore may be used for point measurements in medicine. The immunosensor and optical measuring system are designed to utilize the most common broadband light sources that operate at a central wavelength of 1.55 µm. The results show that it is possible to detect a protein antigen present in a solution by using an all-fiber interferometer coated with specific antibodies. The resulting peak shift can reaches 0.6 nm, which is sufficient to be measured by an optical spectrum analyzer or a spectrometer. A model allowing for estimation of the value of lower limit of detection for such sensors has been elaborated. The elaborated detection system may act as a framework for detection of various antigens and thus it can find future applications in medical diagnostics.

We present the simple microprobe for the investigation of crude oil by a thermal desorption photoionization coupled to Orbitrap mass spectrometry. The droplet of crude oil was placed on the heating element with controllable temperature. The temperature was linearly increased, and crude oil vapors were ionized by a vacuum ultraviolet (VUV) lamp and detected by Orbitrap mass spectrometer. Use of modified Orbitrap allowed introduction of the heating element and VUV lamp directly into the ion funnel and performing experiment not only at atmosphere pressure but also at 20, 10, and 5 torr. We observed that at high pressure protonated CHN compounds dominate in the spectrum, while at the low pressure CH compounds dominate. Similar to previously reported thermogravimetry coupled to photoionization or chemical ionization mass spectrometry systems we were able to separate compounds with different desorption energy and reliably detect low-abundant compounds. Also, we were able to determine the desorption temperature for each compound of the crude oil. We found that temperature of desorption increases linearly with m/ z for compounds that belong to the same homology series (same Kendrick mass defect). This may serve as indirect evidence that such compounds differ only by the length of aliphatic chains attached to some basic structure.

A method is described for high-resolution label-free molecular imaging of human bone tissue. To preserve the lipid content and the heterogeneous structure of osseous tissue, 4 μm thick human bone sections were prepared via cryoembedding and tape-assisted cryosectioning, circumventing the application of organic solvents and a decalcification step. A protocol for comparative mass spectrometry imaging (MSI) on the same section was established for initial analysis with time-of-flight secondary ion mass spectrometry (TOF-SIMS) at a lateral resolution of 10 μm to500 nm, followed by atmospheric pressure scanning microprobe matrix-assisted laser desorption/ionization (AP-SMALDI) Orbitrap MSI at a lateral resolution of 10 μm. This procedure ultimately enabled MSI of lipids, providing the lateral localization of major lipid classes such as glycero-, glycerophospho-, and sphingolipids. Additionally, the applicability of the recently emerged Orbitrap-TOF-SIMS hybrid system was exemplarily examined and compared to the before-mentioned MSI methods.

In this study, graphene wrapped Fe-doped TiO2 (G-TiO2-Fe) spheres were prepared through a simple hydrothermal process. The structural, optical and photocatalytic properties of synthesized composite were characterized by field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), Raman Microprobe (Raman), X-ray photoelectron spectroscopy (XPS) and UV–Vis diffuse reflectance spectrophotometer (DRS). The G-TiO2-Fe composite showed a significant red-shift in light response edge as compared with TiO2. Meanwhile, the band gap exhibited an obvious decline from 3.24 to 2.99 eV. The photocatalytic capacity of G-TiO2-Fe was further evaluated by methylene blue (MB) degradation experiments, and the results indicated that the optimized G-TiO2-Fe exhibited a remarkable increase in photocatalytic activity. The superior photocatalytic performance of the novel material could be ascribed to the synthetic effects of doped Fe and wrapped graphene shells. The unique geometrical configuration and constructive component which modified the TiO2 electronic structure will largely improve the electron transporting efficiency and restrain the electron-hole recombination.

This paper describes the design of a new probe forming lens system consisting of a high excitation magnetic quadrupole lens quadruplet that incorporates a single magnetic octupole lens. This system achieves both a high demagnification and a low spherical aberration compared to conventional high excitation systems and is intended for deployment for the Harbin 300 MeV proton microprobe for applications in space science and ion beam therapy. This relative simplicity of the ion optical design to include a single octupole lens minimizes the risks associated with the constructional and operational precision usually needed for the probe forming lens system and this system could also be deployed in microprobe systems that operate with less magnetically rigid ions. The design of the new system is validated with reference to two independent ion optical computer codes.

FeGa2Se4 single crystals belonging to the promising class of diluted magnetic semiconductors of the AB2X4 type (A is Mn, Fе, Co, or Ni; B is Ga or In; and X is S, Sе, or Te) are investigated; this compound is currently used for designing solid-state magnetically controlled devices. Optically homogeneous bulk FeGa2Se4 single crystals ~14 mm in diameter and ~50 mm long are obtained for the first time from melt by the modified Bridgman method. The elemental composition of the crystals is determined by X-ray spectral microprobe analysis; it corresponds to the specified composition in the initial charge. It is established by X-ray diffraction analysis that this compound is crystallized into a cubic sphalerite-type structure with unitcell parameter a = 5.498 ± 0.005 A. The melting and crystallization temperatures of the grown FeGa2Se4 single crystals are determined by differential thermal analysis. The melting temperature is 1283 K. The microhardness of the single crystals is measured for the first time, the density is determined by the pycnometric method, and the parameters of hyperfine interaction of iron ions are found on the basis of the Mossbauer spectra.

A highly compact biocompatible microprobe type fiber optic temperature sensor was experimentally demonstrated utilizing an inherently high thermo-optic coefficient of DNA biopolymer. The sensor was based on an all-fiber multimode interferometer (MMI) along a coreless silica fiber (CSF) spliced to an end of a single mode fiber. Au film was deposited the CSF end facet to provide a double path for MMI and it also worked as a probe terminal. The circumferential area of CSF was coated with DNA-cetyltrimethylammonium chloride (CTMA) thin solid film, which served as a temperature sensing head. We experimentally investigated thermo-optical properties of DNA-CTMA thin solid films to find its large negative thermo-optical coefficient −4.15 × 10−4/°C in the temperature range from 20 to 70 °C. DNA-CTMA coated fiber optic probe was immersed in a water bath to simulate the bio compatible environment whose temperature was varied in the range from 30 to 70 °C. The proposed sensor showed a high-temperature sensitivity of −0.22 nm/°C in the spectral shifts, and 0.085 dB/°C in the reflected optical power changes. The proposed probe can be readily applied in various types of in vivo point of care temperature monitoring.

Optical fiber microprobe functionalized with Glucose oxidase (GOD) has been proposed for bio-selective and high-sensitive glucose detection. Taking advantages of the free amine groups of 3-aminopropyl- triethoxysilane (APTES), the enzymes (GOD) are immobilized on the multimode microfiber through covalent interaction. Surface characterization offered by optical microscopy, scanning electron microscope and multiphoton laser scanning microscopy provide detailed evidences about the effect of the bio-functionalization. The fabricated microfiber sensor is immersed into glucose solutions at different concentrations to record and analyze the transmission spectrums from an optical sensing interrogator. The experimental results demonstrate that the resonant wavelength shift is linearly correlated with the glucose concentration in the range of 0–3.0 mg/ml with a response coefficient of 1.74 nm/mg −1 ml −1 . Meanwhile, the reported sensor is also proved to be of practical utility by accurately detecting glucose content in animal serum samples. Due to the small size, label-free sensing capacity and excellent practicality, the proposed device has great potential to be applied in the fields like disease diagnosis, clinical analysis and food safety.

Laser ablation ICP-MS is widely applied to geological materials for the in situ analysis of elemental and isotopic compositions at a tens of micrometers scale. Despite the advances in LA-ICP-MS technology made in the last few decades, analyzing features with a micron-sized diameter still faces technical challenges, in particular, contamination from the host material. Here, we provide a quantification strategy to deconvolute the data signal produced when ablating a mixture of the target material and the host, which enables quantification of features that are smaller than the effective size of the laser spot. Our strategy is to purposely ablate mixtures of the target and host material with varying proportions of the two. The resulting mechanical mixtures define a linear trend in compositional space of which the end points can be determined when at least one element is independently known for both phases (e.g., from microprobe analyses or stoichiometry). The theoretical basis of this approach is described. The methods are evaluated by application to experimental samples displaying liquid immiscibility, both at a >50 μm scale where we show that our methods produce equivalent data to traditional data processing, and to samples where the small liquid droplet size prevents traditional analysis. The methods outlined here allow for quantification of features as small as a few micrometers in size on a standard LA-ICP-MS system, and are ideal to analyse melt or fluid inclusions, crystal zonation as well as other small phases in natural or experimental systems.

We report on an abnormal element distribution in silicate glass, induced by 300 kHz, 1030 nm fs laser irradiation. Chemical analysis has taken on the cross section of the laser tracks and also along the writing direction. Energy-dispersive X-ray, wavelength-dispersive spectroscopy and nuclear microprobe demonstrates that no elemental migration occurred after femtosecond laser irradiation, which is quite different from the previous results. The possible mechanism is also briefly discussed.

High energy proton irradiation has many applications to the study of radiation effects in semiconductor devices, biological tissues, proton tomography and space science. Many applications could be extended and enhanced by use of a high energy proton microprobe. However the design of a GeV proton microprobe must address significant challenges including beam collimation that minimizes ion scattering and the probe forming lens system for ions of high rigidity. Here we address the probe forming lens system design subject to several practical constraints including the use of non-superconducting normal magnetic quadrupole lenses, the ability to focus 1–5 GeV protons into 5 µm diameter microprobes and compatibility with the beam parameters of GeV proton accelerators. We show that 2, 3 and 4 lens systems of lenses with effective lengths up to 0.63 m can be employed for this purpose with a demagnification up to 58 and investigate the probe size limitations from beam brightness, lens aberrations and machining precision.

Glass–ceramic composite materials are being investigated for numerous applications (i.e., textile, energy storage, nuclear waste immobilization applications, etc.) due to the chemical durability and flexibility of these materials. Borosilicate and Fe–Al–borosilicate glass–ceramic composites containing brannerite (CeTi2O6) or zirconolite (CaZrTi2O7) crystallites were synthesized at different annealing temperatures. The objective of this study was to understand the interaction of brannerite or zirconolite-type crystallites within the glass matrix and to investigate how the local structure of these composite materials changed with changing synthesis conditions. Powder X-ray diffraction (XRD) and Backscattered electron (BSE) microprobe images have been used to study how the ceramic crystallites dispersed in the glass matrix. X-ray absorption near edge spectroscopy (XANES) spectra were also collected from all glass–ceramic composite materials. Examination of Ti K-, Ce L3-, Zr K-, Si L2,3-, Fe K-, and Al L2,3-edge XANES spectra from the glass–ceramic composites have shown that the annealing temperature, glass composition, and the loading of the ceramic crystallites in the glass matrix can affect the local environment of the glass–ceramic composite materials. A comparison of the glass–ceramic composites containing brannerite or zirconolite crystallites has shown that similar changes in the long range and local structure of these composite materials occur when the synthesis conditions to form these materials or the composition are changed.

Endoscopic optical coherence tomography (OCT) has emerged as a valuable tool for advancing our understanding of the histomorphology of various internal luminal organs and studying the pathogenesis of relevant diseases. To date, this technology affords limited resolving power for discerning subtle pathological changes associated with early diseases. In addition, it remains challenging to access small luminal organs or pass through narrow luminal sections without potentially causing trauma to tissue with a traditional OCT endoscope of a 1-1.5 mm diameter. Here we report an ultracompact (520 µm in outer diameter and 5 mm in rigid length) and super-achromatic microprobe made with a built-in monolithic fiber-optic ball lens, which achieves ultrahigh-resolution (1.7 µm axial resolution in tissue and 6 µm transverse resolution) for endoscopic OCT imaging at 800 nm. Its performance and translational potential are demonstrated by in vivo imaging of a mouse colon, a rat esophagus, and small airways in sheep.

The efficacy of the pulsed DC plasma method in the mitigation of the aggregate alkali reaction, by the deposition of thin films of Al, Ti and Fe nanomaterials on potentially reactive aggregates was investigated from analytical techniques. These included field emission scanning electron microscope, X-ray dispersive energy microprobe, electron back-scatter diffraction, Raman and the resulting expansion in the modified accelerated mortar-bar method. In the 30 days of the test, the values of expansion were obtained in samples with in nature aggregates of (0.77 ± 0.03)% and in those treated of (0.16 ± 0.01)%, (0.16 ± 0.01)% and (0.16 ± 0.00)%, respectively.

Among different configurations of lens systems for nuclear microprobes, the most common one is a triplet of magnetic quadrupole lenses. Nowadays, microanalysis and material modification will undoubtedly benefit from an improvement in spatial resolution. This work presents the results of simulations for improvement of the Oxford Triplet lens system at the Atomki microprobe with consideration of its system parameters and measured beam brightness distribution. For this purpose, an additional single-unit doublet of lenses with two power supplies was introduced. Using earlier developed methods, such a quintuplet system was optimized in order to determine the parameters which provided the highest resolution for different current operational modes with the same microprobe geometry. The tolerances for lens positioning accuracy were also calculated. The obtained quintuplet parameters indicate a resolution improvement for the Atomki microprobe compared to the Oxford Triplet system and these results validate further experimental testing of the proposed quintuplet.

To develop integrated circuit (IC) test of wafer-level packaging, the electromechanical model of microprobe testing process and the IC final test system of wafer-level packaging based on microprobe arrays are first proposed. An electromechanical model of the process of microprobe testing is derived, which is based on the analysis of the collected real-time force and electrical data using designed force sensing system, voltage measuring circuit and loading system. It is found that the contact resistance is a quartic function with respect to the loading force, and the loading force has nonlinear hysteretic damping characteristics with respect to the displacement and speed of the microprobe. The real-time contact resistance is approximately an exponential function of the damping force. Finally, the effectiveness of the proposed electromechanical model on wafer-level packaging testing using our designed new microprobe arrays testing system is confirmed. It will provide models and methods for developing IC final test of wafer-level packaging.

In Harbin, a 300 MeV proton microprobe system is under development for many applications in space science studies including upset studies in microelectronic devices, radiation hardness of materials for satellites and radiation effects in human tissues. The microprobe system, as a component of Space Environment Simulation Research Infrastructure (SESRI), will employ a purpose-built synchrotron to provide the proton beam. Our design goal for the 300 MeV proton microprobe is for energy spread 0.1%, emittance 10π mm mrad, intensity 109 per pulse and a probe size of 10 μm. A magnetic quadrupole lens system will be used to focus the microprobe with a demagnification of 50. This paper presents a systematic investigation of the ion beam optics to optimize the design. The feasibility of the design for the Harbin system is evaluated by comparison with existing microprobe systems designed for high energy ions.

An electrostatic quadrupole doublet lens system has been designed and constructed to provide strong, mass-independent focusing of 1–3 MeV ions to a 1 µm2 spot size. The electrostatic doublet consists of four sets of gold electrodes deposited on quartz rods that are positioned in a precision machined rigid frame. The 38 mm electrodes are fixed in a quadrupole doublet arrangement having a bore diameter of 6.35 mm. The coating process allows uniform, 360° coverage with minimal edge defects. Determined via optical interferometry, typical surface roughness is 6 nm peak to valley. Radial and coaxial alignment of the electrodes within the frame is accomplished by using a combination of rigid and adjustable mechanical supports. Axial alignment along the ion beam is accomplished via external manipulators. COMSOL Multiphysics® v5.2 and Propagate Rays and Aberrations by Matrices (PRAM) were used to simulate ion trajectories through the system.

Nickel-based alloys as candidate materials for Thorium Molten Salt Reactor (TMSR), need to be used under high temperature in molten salt environment. In order to ensure the safety of the reactor running, it is necessary to study the elemental move characteristic of nickel-based alloys in the high temperature molten salts. In this work, the scanning nuclear microprobe at Fudan University was applied to study the elemental move. The Nickel-based alloy samples were corroded by molten salt at different temperatures. The element concentrations in the Nickel-based alloys samples were determined by the scanning nuclear microprobe. Micro-PIXE results showed that the element concentrations changed from the interior to the exterior of the alloy samples after the corrosion.

Plutonium plays an important role within nuclear waste materials because of its long half-life and high radiotoxicity. The aim of this study was to investigate with high spatial resolution the reactivity of the more oxidized forms of Pu(V,VI) within Opalinus Clay (OPA) rock, a heterogeneous, natural argillaceous rock considered as a potential repository host. A combination of synchrotron based X-ray microprobe and bulk techniques was used to study the spatial distribution and molecular speciation of Pu within OPA after diffusion and sorption processes. Microscopic chemical images revealed a pronounced impact of geochemical heterogeneities concerning the reactivity of the natural barrier material. Spatially resolved X-ray absorption spectroscopy documented a reduction of the highly soluble Pu(V,VI) to the less mobile Pu(IV) within the argillaceous rock material, while bulk investigations showed second-shell scattering contributions, indicating an inner-sphere sorption of Pu on OPA components. Microdiffraction imaging identified the clay mineral kaolinite to play a key role in the immobilization of the reduced Pu. The findings provide strong evidence that reduction and immobilization do not occur as linked processes on a single reactive phase but as decoupled, subsequent, and spatially separated reactions involving different phases of the OPA.

The NaOH/metakaolin ratio and crystallization time were studied for the synthesis of zeolite NaA from a sample of kaolin from a Capim mine. The tests were carried out by using statistical design with axial points and replication of the central point. The samples obtained were characterized by X-ray diffraction (DRX), scanning electron microscopy and chemical analysis using a microprobe EPMA. The results showed that there is a relationship between the amount of NaOH added and crystallization time. The tests carried out using the lowest NaOH/metakaolin ratio (0.5) and the shortest time (4 h) produced a non-crystalline material. On the other hand, increasing the NaOH/metakaolin ratio and the crystallization time led to the formation of a NaA phase with a high structural level, but with the presence of a sodalite phase as an impurity.

An ultrasonic probe consisting of two optical fiber-based miniaturized transducers for wideband ultrasound emission and detection is employed for the characterization of in vitro biological tissues. In the probe, ultrasound generation is obtained by thermoelastic emission from patterned carbon films in Micro-Opto-Mechanical-System (MOMS) devices mounted on the tip of an optical fiber, whereas acousto-optical detection is performed in a similar way by a miniaturized polymeric interferometer. The microprobe presents a wide, flat bandwidth that is a very attractive feature for ultrasonic investigation, especially for tissue characterization. Thanks to the very high ultrasonic frequencies obtained, the probe is able to reveal different details of the object under investigation by analyzing the ultrasonic signal within different frequencies ranges, as shown by specific experiments performed on a patterned cornstarch flour sample in vitro. This is confirmed by measurements executed to determine the lateral resolution of the microprobe at different frequencies of about 70 mu m at 120 MHz. Moreover, measurements performed with the wideband probe in pulsed-echo mode on a histological finding of porcine kidney are presented, on which two different spectral signal processing algorithms are applied. After processing, the ultrasonic spectral features show a peculiar spatial distribution on the sample, which is expected to depend on different ultrasonic backscattering properties of the analyzed tissues. (C) 2016 Elsevier B.V. All rights reserved.

This chapter describes samples and analytical techniques used for studying the mineralogy and the shock-induced effects in the Yanzhuang meteorite. These techniques are optical microscopy (OM), scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDXA), electron probe microanalysis (EPMA), Raman microprobe analysis (RMA), X-ray micro-diffraction analysis (XRMD), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM), instrumental neutron activation analysis (INAA), proton-induced X-ray emission analysis (PIXE), and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS).

Powder diffraction 35, 1-4 (2020). doi:10.1017/S0885715620000536, A provisional setup for X-ray microprobe experiments at 35 keV is described. It is based on compoundrefractive lenses (CRLs) for nanofocusing and a Vortex silicon drift detector with 2 mm sensorthickness for increased sensitivity at high energies. The Microprobe experiment (PETRA III) generallyuses Kirkpatrick-Baez mirrors for submicrometer focusing in the energy range of 5–21 keV.However, various types of scanning X-ray microscopy experiments require higher excitation energies.The CRL optics were characterized by X-ray ptychography and X-ray fluorescence (XRF) knife edgescans on a siemens star pattern and showed beam sizes down to 110 nm. The performance of the newsetup for microscopic X-ray diffraction (XRD)–XRF scanning X-ray microscopy measurements at35 keV is demonstrated on a cross-section of a painting fragment., Published by Cambridge Univ. Press, Cambridge

Recent studies in which X-ray beams of macroscopic to (sub) microscopic dimensions were used for non-destructive analysis and characterization of pigments, paint micro samples and/or entire paintings by Vincent van Gogh are concisely reviewed. The overview presented encompasses the use of laboratory and synchrotron radiation-based instrumentation and deals with the use of several variants of X-ray fluorescence (XRF) as a method of elemental analysis and imaging as well as with the combined use of X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Microscopic and macroscopic XRF are variants of the method that are well suited to visualize the elemental distribution of key elements, mostly metals, present in paint multi layers, either on the length scale from 1–100 μm inside micro samples taken from paintings or on the 1–100 cm length scale when the (subsurface) distribution of specific pigments in entire paintings is concerned. In the context of the characterization of van Gogh's pigments subject to natural degradation, the use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that have taken place. However, at synchrotron facilities, combinations of μ-XRF with related methods such as μ-XAS and μ-XRD have proven themselves to be very suitable for such studies. Their use is often combined with microscopic Fourier transform infra-red (μ-FTIR) spectroscopy since this method delivers complementary information at more or less the same length scale as the X-ray microprobe techniques. Also in the context of macroscopic imaging of works of art, the complementary use of X-ray based and infra-red based imaging appears very promising; some recent developments are discussed.

Surface-enhanced Raman scattering (SERS) is a highly sensitive and versatile analytical technique that can be implemented on an optical fiber platform for use in challenging environments. This work has sought to address a major factor limiting the use of optical fibers for SERS analytical applications, namely the silica Raman background generated inside the fiber can make it difficult to detect the target analyte. Two different approaches were investigated to address this problem. Firstly, double clad fiber (DCF) was found to increase the collection of Raman scattered signal from the analyte, giving up to twelve-fold improvement in the signal-to-background ratio (SBR). Secondly, a prototype microfilter was manufactured by femtosecond laser machining and attached directly to the DCF tip. Its performance in rejecting background signal was then evaluated. When taking the lengths of the optical fibers into account, the filtered DCF microprobe delivers 7.0 SBR.cm, while the bare DCF probe provided 3.0 SBR.cm. Therefore, the microfilter assembly more than doubled the performance of the SERS probe and, with further optimization in future, it shows great promise for ultra-compact SERS and Raman optical fiber probes.

We describe a method for obtaining the optimal design of a normal incidence Scanning Helium Microscope (SHeM). Scanning helium microscopy is a recently developed technique that uses low energy neutral helium atoms as a probe to image the surface of a sample without causing damage. After estimating the variation of source brightness with nozzle size and pressure, we perform a constrained optimisation to determine the optimal geometry of the instrument (i.e. the geometry that maximises intensity) for a given target resolution. For an instrument using a pinhole to form the helium microprobe, the source and atom optics are separable and Lagrange multipliers are used to obtain an analytic expression for the optimal parameters. For an instrument using a zone plate as the focal element, the whole optical system must be considered and a numerical approach has been applied. Unlike previous numerical methods for optimisation, our approach provides insight into the effect and significance of each instrumental parameter, enabling an intuitive understanding of effect of the SHeM geometry. We show that for an instrument with a working distance of 1 mm, a zone plate with a minimum feature size of 25 nm becomes the advantageous focussing element if the desired beam standard deviation is below about 300 nm.