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Global demand for milk is increasing with population growth, but industry ethics are a concern due to profit-driven practices. In this work, a surface-active electrode composite was synthesized using a surface-modified Corning glass electrode (TiO2-LL@AgNps) coated with phytofabricated silver nanoparticles from Leucaena leucocephala leaf extracts. To investigate the structural properties of the phytofabricated silver nanoparticles, various characterization techniques were used, including scanning and transmission electron microscopy (TEM), UV-visible, X-ray diffraction (XRD), Fourier transform infrared (FTIR), and energy-dispersive X-ray (EDX) spectroscopy. The findings revealed the synthesis of crystalline, spherical silver nanoparticles with an average size of 11.93 nm and a maximum absorption of 436 nm. This surface-modified electrode was made from synthesized silver nanoparticles and used for the electrochemical detection of urea in both artificial samples and real milk. The detection was based on the measurement of the induced potential resulting from the surface interaction between urea and the developed electrode. The composite was successfully used for urea detection. The sensing parameters, including the sensing range (5.0×10−6 M to 25.0×10−6 M), sensitivity (5.0 mV µM−1 cm−2), and detection limit (2.48× 10−6 M). The developed electrode exhibited a response time of 5 min and maintained stability for 28 days. This environmentally friendly sensor is comparable to the spectroscopic approach and shows minimal interference from other substances present in milk. [ABSTRACT FROM AUTHOR]

The features of deformed microstructure and fracture of 12% chromium ferritic-martensitic steel EP-823 tensile specimens subjected to long-term (1000 h) aging at 580 °С are investigated by scanning and transmission electron microscopy. It is shown that they are determined by the tensile test temperature (20 or 700 °C). The high tensile temperature promotes the process of recovery and dynamic strain aging in the ferritic-martensitic structure. The steel ruptures by the mechanism of ductile dimple transcrystalline fracture at all temperatures. [ABSTRACT FROM AUTHOR]

The quenching from 900 °C and subsequent tempering at 280 °C and 500 °C performed on two low-alloyed steels with different carbon content produced as-quenched and quench-tempered lath martensite structures. The effect of tempering temperature on the microstructures and precipitation sequences was investigated by thermodynamic calculations and by scanning and transmission electron microscopy. The selected area diffraction analysis of the second phase particles in the thin foils reveal the precipitation of transition η-carbides and formation of cementite phase during tempering. [ABSTRACT FROM AUTHOR]

Uniaxial creep tests in tension of as-cast nickel-based B1914 and INC738LC superalloys were carried out at testing temperatures of 800 and 950°C and at the applied stresses ranging from 100 to 700 MPa. Creep tests were followed by microstructural and fractographic investigations using scanning and transmission electron microscopy. The experimentally determined creep deformation and fracture characteristics of both superalloys were analysed by linking them to the identified creep degradation mechanisms, in terms of empirical formulas for the creep life assessment, and by the creep damage tolerance factor λCDF as an important outcome of the continuum damage (CDM) approach. It was found that the experimental data obey the Monkman-Grant relationship and imply a close link between the creep deformation and fracture processes. Fractographic investigation revealed that, under testing conditions, the creep fracture is a brittle mostly mixed transgranular and intergranular mode, resulting in relatively low values of the fracture strain. [ABSTRACT FROM AUTHOR]

Elemental doping and carbon coating on the electrode are able to increase the battery's performance to be a good energy storage. In this case, some studies are necessary to confirm the quality of the cathode material, LiFePO4 on the Li-ion based battery material (LIB). Here we report the study of structure and morphology of LiFePO4 by silicon doping at the P-atom atomic position and carbon coating (henceforth called as LFP-Si) utilizing the X-Ray diffractometer, the Fourier-transform infrared technique, and both the scanning and transmission electron microscopy (SEM & TEM), as a preliminary investigation to know the structure and morphology of LiFePO4 after elemental doping and carbon coating. All characterization results are essential for the improvement of the performance of LiFePO4/C doped material. [ABSTRACT FROM AUTHOR]

The synthesis of lead (II) sulphide nanoparticles converts solar energy into chemical energy. Things appear to be developing on the surface. Nanostructured lead sulphate and spherical or cubic chain-like chains are both feasible. Transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, selective electron diffraction, oil/visible/near-infrared spectrophotometric spectroscopy, and lead (II) sulphate in dust are all used to examine the material. X-ray diffraction and X-ray scattering examinations of the powder confirm the presence of lead (II) sulphate and its crystal structure and size. Transmission electron microscopy and scanning electron microscopy analyse structural and morphological details. According to data from infrared spectroscopy, lead sulphate is produced. When exposed to light, the photosynthetic behaviour of lead (II) sulphate samples during the photolysis of methyl blue is easily visible. These results show that a small number of lead (II) sulphate nanoparticles may provide a significant quantity of photosynthetic activity. We intend to use narrow-bandwidth photosynthesis to decompose methyl blue pigments.. [ABSTRACT FROM AUTHOR]

The present work is focused on the overview of atomic models of εn decagonal quasi crystalline approximants in the Al-Pd-Co system. Atomic structural models of the structural variants ε6, ε16, ε22, ε28 and ε34 were created using ab-initio calculations and/or Monte Carlo simulation. Atomic models were calculated based on the experimental results obtained by X-ray diffraction and scanning transmission electron microscopy. Good agreement was obtained between calculated and experimentally observed atomic structures of the εn phase. The calculated data for the structural variant ε28 are available in the appendix, as CIF file in text format. [ABSTRACT FROM AUTHOR]

Metallic nano components are a standard part of a variety of nano-electro-mechanical devices. For bonding of these components, sound quality thin joints are required. For nanoscale joining and bonding, advantageous properties could be found in core-shell NiTi nanoparticles. Characterization of morphology, size, shell thickness, and composition of core-shell NiTi nanoparticles prepared by DC magnetron sputtering using two planar magnetron sources was done by transmission electron microscopy and scanning transmission microscopy with energy dispersive X-ray spectroscopy. The observation of the nanoparticles at high temperatures was performed by in situ transmission electron microscopy in a heating holder, and the resulting products were characterized. [ABSTRACT FROM AUTHOR]

Nanoparticles have many applications in the biomedical field primarily for drug delivery, cancer therapy, and detection of pathogenic microorganisms. In this study, Nano-pomegranate extract synthesized using pomegranate (peel) extract prepared by Sol-gel Nano-technique by ultrasonic pyrolysis method in aqueous solution at a temperature (0-80)°C to evaluated for their antibacterial potential and antioxidant. The morphology and size of the Nano-pomegranate extract were further characterized as spherical in shape with an average size of 58.10 nm in diameter by scanning electron microscopy and transmission electron microscopy. EDX analysis clearly displayed the presence of two high signal (sodium and carbon) with different element (C,O,AL,Si,cl and Mg). The size of Nano-pomegranate was determined as 26 nm in the dominate peak (40.583) in reflections were confirmed by X-ray diffraction and X-ray photoelectron spectroscopy. In other way, Nano-extract given orally for 4 weeks in 3 concentration (0.1,0.05 &0.025)ml/kg b.w. the result indicated that Nano extract didn't show any mortality or behavioral changes during the long period of treatment due to higher content of antioxidant compounds like different active ingredient phenolic compounds, flavonoids, carbohydrate, tannin and saponin. The synthesized Nano-pomegranate exhibited efficient antibacterial activity against Escherichia coli (28 mm) and Staph. aureus (28 mm) compared to crude extract and was (24)mm and (25) mm. [ABSTRACT FROM AUTHOR]

The present work investigates the role of process parameters on the wear property of friction surfaced Al 6061 coating on Al 2024 substrate material. For this study, after many optimization experiments, four samples with different friction surface forces were prepared. Several mechanical and metallographic characterizations were conducted on the samples that including hardness analysis, metallographic analysis using optical microscopy, scanning electron microscopy and transmission electron microscopy, elemental analysis using energy dispersive spectroscopy, and phase analysis using X-ray diffraction spectroscopy technique. From the results, it is found that the hardness, as well as wear property, has been improved with the increase of friction surfacing force. [ABSTRACT FROM AUTHOR]

A method to obtain films of hexane-insoluble asphaltenes from a toluene solution of medium-temperature coaltar pitch is discussed. To describe topographic, morphological and structural features of the obtained films of asphaltene associates they were studied by scanning and transmission electron microscopy methods. The surface morphology and structure of the samples were studied by scanning and transmission electron microscopy (SEM JEOL JSM 6390 LV and TEM JEOL JEM 2100). Heat treatment of the films was carried out in the presence of air in an electric chamber furnace (EСPS-10V). Elemental analysis of the samples was performed using an inductively coupled plasma emission spectrometer (iCAP 6500 Duo). Structural changes of substances and transformations were investigated by mean of IR spectroscopy (IR-Fourier spectrometer INFRALUM) in couple with synchronous thermal analysis (STA NETZSCH 409 PG Luxx). The crystal structure of the samples was investigated by X-ray diffraction. The process of thermal decomposition of hexane-insoluble asphaltenes in the temperature range from 20 to 800°C was investigated. It was found that at 495°C a process of the film substance structuring occurred. The formation of graphite-like structures during annealing of the films was observed using IR spectroscopy and X-ray diffraction. [ABSTRACT FROM AUTHOR]

Pure magnesium with a coarse-grained structure was deformed by a backward extrusion (BE) method at room temperature at one step. As a result, a Mg-cup with a wall of 1 mm thickness was obtained. The strain (e) of Mg in this process amounted about 2.7. The ХRD-analysis has revealed that there is a weak (0001) basal texture of Mg after the BE treatment. The scanning and transmission electron microscopies have shown a significant grain refinement of Mg and the average grain size of about 5 µm. [ABSTRACT FROM AUTHOR]

Colleges across the United States must produce more engineering graduates in order to keep up with demands in the engineering workforce. Population trends indicate that women and minorities are highly underrepresented in the STEM fields therefore recruitment and retention of these populations is critical to closing the predicted gap in the workforce. Perkins Peer Advisement is a grant funded program at New York City College of Technology (City Tech) committed to increasing enrollment and retention of nontraditional students in engineering technology programs. Program activities include professional development, mentoring, and community outreach. Participants of the program have higher retention rates than the average reported for these majors. For female students, the one-year retention rates were 85% for participants compared to about 51% for all female students in fall 2017 and 78% for participants compared to about 60% for all female students in fall 2018. For Hispanic students, the one-year retention rates were 52% for participants compared to about 44% for all Hispanic students in fall 2017 and 76% for participants compared to about 46% for all Hispanic students in fall 2018. The program provides a successful model for mentoring, recruiting, and retaining females and minorities in STEM; empowers students with the resources to succeed academically and professionally, provides positive role models, and engages participants in community outreach. [ABSTRACT FROM AUTHOR]

Creative thinking skills are a major challenge in education today. Students with good creative thinking skills can certainly compete in the global era. Creative thinking skills need to be trained through STEM learning. This research is focused on improving high school students' creative thinking skills in the optical instrument topic through the development of STEM worksheets. The developed worksheet provides students with experiences designing, creating projects, making videos, uploading assignments, analyzing projects, and discussions. The varied valuable experiences with integrating technology and engineering in learning are advantages of the worksheets developed. These experiences have not been provided in previous worksheets. ADDIE design with five stages is used as a design in worksheet development. Three experts validated the development results; after being declared valid, the readability level was tested on 15 students. The worksheet is implemented in one class with the one-group pretest-posttest design used to measure the practicality and effectiveness of the worksheet. The t-test was used to analyze the differences in creative thinking skills before and after learning physics using a STEM worksheet. The results showed a significant difference in students' creative thinking skills before and after experiencing learning using worksheets developed. The improvement also showed form N-Gain score of 0.16. In conclusion, the results of the STEM integrated worksheet are valid, practical used, and effective for improving students' creative thinking skills. The development of STEM worksheets on different materials needs to be considered. [ABSTRACT FROM AUTHOR]

Using scanning and transmission electron microscopy, we studied the features of the internal oxidation of a low-activation vanadium alloy V–Cr–Zr. It has been established that under the conditions of chemical-heat treatment, the mechanism of nonequilibrium internal oxidation is realized with the formation of fine ZrO2 particles. It is shown that the width of the front of internal oxidation is comparable with the half-thickness of the sample. The advancement of internal oxidation front is accompanied by a significant increase in microhardness. It is assumed that the implementation of the mechanism of non-equilibrium internal oxidation provides uniform conditions for the nucleation and growth of zirconium oxides and a high dispersion of the heterophase structure. [ABSTRACT FROM AUTHOR]

Magnesium oxybromides are analogue substances to magnesium oxychlorides, commonly known as Sorel cements. In this contribution, we prepared and characterized pure Mg2(OH)3Br·4H2O. The phase composition was evaluated by X-ray diffraction. The chemical composition was analyzed using X-ray fluorescence and energy dispersive spectroscopy. Also, scanning electron microscopy and transmission electron microscopy was used to analyse the microstructure. In addition, thermal stability was tested using simultaneous thermal analysis. [ABSTRACT FROM AUTHOR]

This conference contribution is focused on decoration of WS2 nanotubes (NT-WS2) with gold and silver nanoparticles via facile routes implying direct reaction of tungsten disulfide with water-soluble AuIII and AgI species at 100°C. The underlying mechanism of these interactions will be discussed in details based on extensive studies of reaction mixtures and resulting metal–NT-WS2 nanocomposites, including thorough X-ray photoelectron spectroscopy (XPS) analysis. Surprising features in optical spectra of the designed nanocomposites would be reported, including suppression of plasmon resonance in tiny noble metal nanoparticles (< 10 nm in diameter) grown onto NT-WS2. The plasmonic features of individual gold nanoparticles on the surface of disulfide nanotube were also characterized by electron energy loss spectroscopy in scanning transmission electron microscopy mode (STEM-EELS). Photoresistive NO2−sensing response of NT-WS2 under green light illumination (λmax = 530 nm) and its enhancement by plasmonic gold "nanoantennas" will be reported as well. [ABSTRACT FROM AUTHOR]

The structure, phase composition and properties of the composite electroexplosion coating of ZnO-Ag system subjected to the irradiation by the high intense electron beam have been studied for the first time. The combined processing including the electroexplosion spraying of the coating of ZnO-Ag system and its subsequent electron beam processing results in the formation of multilayer structure of the coating. By the methods of metallography, scanning and transmission electron microscopy, X-ray structural analysis the investigations into the phase and elemental composition, defect substructure of the coating and the transition layer between the coatings and copper electrical contact have been carried out. The electron beam melts and homogenizes the surface layer of the composite electroexplosion coating of ZnO-Ag system to the depth of 35–40 µm. The effect of the electron beam leads to the formation of the nanocrystalline phases of Ag, ZnO, Cu, CuZn, Ag5Zn8, Cu2O, Ag2O,Cu0.67Zn0.33, AgZn. [ABSTRACT FROM AUTHOR]

Hematite (α-Fe2O3) nanopowders were successfully prepared via a hydrothermal route. In the present study the effect of divalent metals M (Cu, Zn, Co and Ni) adding on the structural properties of the hematite is investigated. During powder preparation, the used solution was composed of 75% of iron chloride as iron source and 25% of M (Cu, Zn, Co and Ni) chloride. The morphology and microstructure of the synthesized nanopowders were analyzed by using scanning and transmission electron microscopy (SEM and TEM, respectively) analysis and X-ray diffraction (XRD). The XRD analysis reveals that no spinel phase was formed. Moreover, no secondary oxide phases such as CuO, ZnO or CoO are formed suggesting that these atoms are diluted in the hematite network. The TEM and SEM observations results, indicated that the prepared powder is mainly composed of agglomeration of homogeneous spherical grains with average size ranged from 140 to 280 nm. The prepared nanoparticles were tested in waste water treatment. The nanoparticles are added to a real polluted water extracted from the university. Inductively coupled plasma mass spectrometer (ICP-MS) was used to determine the elements amount in the water. The obtained results indicated that the based ferrite nanoparticles have reduced the amount of the contaminant heavy metals such as Pb, As, Cs and Al present in the waste water. We noticed that Co: Fe2O3 and Cu: Fe2O3 nanoparticles were more efficient, this is due to their lower cristallinity coefficient that enhances their specific surface and metal adsorption sites. [ABSTRACT FROM AUTHOR]

A comparison on Photo-catalytic activity of pure and Ag-ZnS nanocomposites using histidine as a capping agent have been reported here. The synthesized samples were characterized by X-ray diffraction spectroscopy, Field emission scanning electron microscopy, High resolution transmission electron microscopy and Ultraviolet-Visible spectroscopy. The photocatalytic activity of as-prepared samples were investigated under sunlight using Rhodamine B. The photocatalytic activity of ZnS was observed to be decreased by the incorporation of Ag. [ABSTRACT FROM AUTHOR]

This article highlights the influence of ternary material combination of thermoelectric 0.5Bi2Te3 (BT), ferroelectric 0.5(PLZT9/65/35) (PLZT) nanopowders dispersed in polymer PVDF matrix to form a 0.5Bi2Te3-0.5[Pb0.91La0.09(Zr0.65Ti0.35)0.9775O3]-PVDF nanocomposite thin film. BT and PLZT were prepared by using simple precipitation method to form 0.5BT-0.5PLZT-PVDF nanocomposite thin film. As heat treated BT and PLZT were characterized for phase analysis by powder X-ray diffraction, and microstructure studies by scanning electron microscopy and transmission electron microscopy. Nanocomposite thin films were characterized for room temperature dielectric, thermoelectric and ferroelectric studies. XRD patterns attested clear crystalline mixture of Bi2Te3 trigonal showing rhombohedral structure and perovskite PLZT showing ternary FERH, FETET, and FECUBIC structures at the morphotrophic phase boundary. SEM with EDS and TEM results of thermoelectric Bi2Te3, ferroelectric (PLZT:9/65/35) and 0.5Bi2Te3-0.5[Pb0.91La0.09(Zr0.65Ti0.35)0.9775O3] are reported. The nanoparticles of this system ranged between 17 nm and 82 nm. Dielectric, thermoelectric and ferroelectric results of the 0.5Bi2Te3-0.5[Pb0.91La0.09(Zr0.65Ti0.35)0.9775O3]-PVDF nanocomposite thin film was discussed. The remanent and spontaneous polarization and coercive field of BT-PLZT-PVDF film are observed as 2.52 µC/cm², 3.28 µC/cm and 196.63 kV/cm, respectively that could be interesting candidate for possible futuristic energy harvesting, biomedical and smart applications. [ABSTRACT FROM AUTHOR]

Micro and nanoparticles of titanium dioxide are nowadays produced worldwide for a range of applications. In our project we focus on potential use of titanium dioxide particles as UV absorber (anti-UV protective coating) for wooden construction structures. We investigate the influence of different synthesis methods on particles’ morphology. Hence, material characterization has an important place in our research. Electron microscopy is a powerful tool to obtain information about the morphology of particles and their surface features. Nevertheless, for a reliable ultrahigh resolution image specific procedures regarding sample preparation must be adopted, and the measurement conditions must be carefully chosen. Usually this part of research is underestimated, and that is why we decided to address it in our paper. Scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM) and transmission electron microscopy (TEM) will be discussed. We will compare our experimental studies with current state of the art showing the influence of substrate (carbon tape or silicon wafers) and sample preparation on the obtained images. Titanium dioxide is a semiconductor therefore in case of observation of non-coated specimen in high vacuum mode one has to deal with the unavoidable charging effect. To reduce the signal‐to‐noise ratio, low energies were used (5 and 10kV) as well as different ways of obtaining the image (photo versus integrated image). Removing possible contaminants (thin hydrocarbon film) from the specimens’ surface by means of ultraviolet radiation revealed to be helpful. In order to complete the information obtained from scanning electron microscopy, scanning transmission and transmission electron microscopy were used as complementary methods. [ABSTRACT FROM AUTHOR]

Recent advances in detector technology, combined with continuous 2D Piezo scanning, are posing a significant challenge on data analysis. With the EigerX 4M detector by Dectris, for example, four million single-photon counting pixels can be read out at 750 Hz frame rate. Although compressed, this yields a data stream of roughly 100 MB per second. For analysis, data need to be uncompressed, yielding a data rate of more than 6 GB per second. To deal with the data obtained at such high rates in scanning transmission x-ray microscopy (STXM) measurements, we have developed a dedicated STXM analysis cluster, the “Heinzelmännchen system”. With a special software, 24 computing nodes can process up to 3 500 EigerX frames per second, i.e. about four times as fast as the data is acquired. This allows for new algorithms to be developed, when datasets need to be processed multiple times in iterative schemes. [ABSTRACT FROM AUTHOR]

A soft X-ray nanoscopy beamline (SXNB) at the Taiwan Photon Source (TPS) is designed to deliver photons of 90 – 2,500 eV from an elliptically polarized undulator to two state-of-the-art microscopy stations hosting the scanning transmission X-ray microscope (STXM) and the photoelectron related imaging and nanoscope (PRINS), respectively. The heart of SXNB is an active grating monochromator (AGM) that optimizes the flux and energy resolution at the same time while maintaining a stable focal spot on the sample. This article describes the design concept, optical layout, and simulation results of SXNB. [ABSTRACT FROM AUTHOR]

The nanocomposite PbSnF4@SWNT was obtained by capillary technique for the first time. This nanocomposite was investigated using X-ray diffraction phase analysis (XRD), high-resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDX). SWNT diameter is ~2 nm. Lead tetrafluorostannate (PbSnF4) monoclinic modification (space group P2/n) was identified by XRD analysis. The periodicity of the crystal plane (201) along the tube axis is ~3.2Å. The distortion of plane is 11° with respect to the nanotube axis. The model of PbSnF4 single crystal contains ~168 atoms. The structure of 1D PbSnF4@SWNT nanocomposite and HREM image were modelled. [ABSTRACT FROM AUTHOR]

In this present work we have synthesized few layered MnO2 nanosheets by mixed solvent exfoliation process for the application as electrode material of in-plane supercapacitor. The Structure and surface morphology of the as prepared samples are characterized by Raman, Transmission electron microscopy and Scanning electron microscopy. The patterns of the hybrids were directly fabricated by (50: 50 wt %) mixture of MnO2 and SWCNT dispersions with the help of a customized mask, and directly transferred onto a flexible PET substrate. Remarkably, the prepared in-plane supercapacitors deliver high energy density of 2.62mWh/cm2. Furthermore, our supercapacitors shows exceptional flexibility and stable performance under bending conditions [ABSTRACT FROM AUTHOR]

Biological synthesis of different metallic and/or oxide nanoparticles and their applications especially in agriculture and biomedical sciences are gaining prominence nowadays due to their handy and reproducible synthetic protocols which are cost-effective and eco-friendly. In this work, green synthesis of zinc oxide nanoparticles (ZnO NPs) using the alcoholic extract of Azadirachta indica as a reducing and stabilizing agent has been presented. Formation of ZnO NPs was confirmed by X-ray diffraction, scanning and transmission electron microscopy techniques. The phytochemicals responsible for nano-transformation were principally alkaloids, flavanoids, terpenoids, tannins and organic acids present in the Azadirachta indica leaves. The synthesized ZnO NPs were used for antimicrobial assays by disc diffusion method against Staphylococcus aureus and Candida albicans. Results showed that ZnO NPs may act as antimicrobial agent especially against skin infections. [ABSTRACT FROM AUTHOR]

The morphological and optical properties of noble metal nanoparticles prepared by picosecond laser generated plasmas in water were investigated. First, the ablation efficiency was maximized searching the optimal focusing conditions. The nanoparticle size, measured by Scanning Transmission Electron Microscopy, strongly depends on the laser fluence, keeping fixed the other deposition parameters such as the target to scanner objective distance and laser repetition frequency. STEM images indicate narrow gradients of NP sizes. Hence the optimization of ablation parameters favours a fine tuning of nanoparticles. UV-Visible spectroscopy helped to determine the appropriate laser wavelength to resonantly excite the localized surface plasmon to carry out Surface Enhanced Raman Scattering (SERS) measurements. The SERS activity of Ag and Au substrates, obtained spraying the colloids synthesized in water, was tested using crystal violet as a probe molecule. The good SERS performance, observed at excitation wavelength 785 nm, is attributed to aggregation phenomena of nanoparticles sprayed on the support. [ABSTRACT FROM AUTHOR]

The sub-50 nm Indium Arsenide Composite Channel (IACC) High Electron Mobility Transistors (HEMTs) are fabricated on 100 mm Indium Phosphide (InP) substrates. This technology offers the best performance for low-noise and high-frequency, space and military applications. Typical failure mechanisms are observed in III-V HEMT technologies, including gate sinking, impact ionization and electromigration. Experiments were conducted to understand failure mechanisms of the IACC HEMTs by life testing devices at accelerated temperatures and biases; their electrical characteristics were measured at each stress interval. Since many of the known III-V semiconductor failure mechanisms physically degrade or damage HEMTs, cross-sections are important to prepare to detect these mechanisms. In this presentation, advanced microscopy techniques with sub-nanometer resolutions, will examine physical characteristics of the HEMT at the atomic scale. The microscopy techniques will include a Focused Ion Beam/Scanning Electron Microscope (FIB/SEM) to prepare cross-sections of the HEMT and a Scanning Transmission Electron Microscope (STEM) to examine the physical features. A Nanomill is used to supplement the FIB by further thinning the sample to see the atomic features and remove any amorphous layers left behind by the FIB. This presentation will show how the Nanomill helps to uncover the atomic-scale features of the HEMT. [ABSTRACT FROM AUTHOR]

The structure of a b = <1100> dislocation formed in the {1100}/<1120> 2° low-angle grain boundary of alumina was observed by scanning transmission electron microscopy (STEM). It was found that the <1100> dislocation dissociates into 1/3<1100> partial-dislocation triplets with two stacking faults on the {1100} plane. The atomic structure of the {1100} stacking faults was characterized by annular bright field STEM (ABF-STEM). The two stacking faults were found to have a stacking sequence of ...ABCCABC... and ...ABCBCAB..., which is consistent with a former report. ABF-STEM image simulation was performed using structure models with the {1100} stacking faults optimized by first-principles calculations. The overall features of the experimental and the simulated results agree with each other. However, slight differences in contrast were recognized in the vicinity of the stacking faults, suggesting that there are small differences between the observed structures and the theoretical models. [ABSTRACT FROM AUTHOR]

The article examines the role of electronic excitation and selective displacement damage in the structure of defects and microstructure evolution in oxide ceramics. Topics covered include the use of transmission electronic microscopy (TEM) and scanning transmission electron microscopy (STEM) to examine the effects of selective displacement damage of oxygen sublattice in fluorite-type oxides and atomic structure of ion tracks in CeO2 and MgAl2O4.

Nanostructure investigation on the post implantation by Fe-B and NiFe-B on CVD diamond/Si(111) film have been studied by means of STEM related to their GMR phenomena. Two samples were investigated carefully, firstly sample is post NiFe-B at E=70keV and dose= 1015 ions/cm2 (denoted as A-E3D1). Secondly, is post FeB at E=20 keV and dose= 1015 ions/cm2 (denoted as B-E1D1). Based on FPP measurement at room temperature (RT) and Happlied=8 kOe , A-E3D1 sample has MR ratio almost 80% and MR ratio in B-E1D1 sample is 45%. Based on STEM-EDX investigation, there are two aspects of how MR ratio of A-E3D1 more higher than those of B-E1D1. Firstly, surface nanostructure on the top of AE3D1 film is more grazing than on the top of B-E1D1. Analysis with Scanning Transmission Electron Microscope (STEM) equipped with Electron Energy Loss Spectroscopy (EELS) the growth of amorphous carbon layer on top of the implanted diamond film with thickness around 100 nm and only 20 nm on the no implanted sample have observed. Boron atoms were found inside the carbon amorphous layer distributed homogenously. Secondly, oxygen content at the interface between diamond film and silicon substrate in sample A-E3D1 was lower than those in B-E1D1 sample. This condition gives the resistance value in A-E3D1 lower than value in B-E1D1. This result is close to the Raman Spectroscopy data measurement which obviously suggests changes on the Raman spectrum due to implantation related to Oxygen excitation from B-E1D1 sample. [ABSTRACT FROM AUTHOR]

Scanning Transmission X-ray Microscopy (STXM) is a relatively recent and rapidly growing X-ray imaging technique with niche capabilities that are applicable across a wide set of scientific disciplines. Over the years since its invention, technological progress has allowed a much greater volume and wider variety of data to be recorded, while the flexibility of the technique has also given rise to many variations, utilizing different contrast mechanisms, detection modes, scanning modes, sample configurations and sample environments. There is, therefore, increasing dissatisfaction with the predominant data file format. Here, we present a new file format, NXstxm, based on the NeXus standard and utilizing the HDF5 container format. The design of the format is based on principles of 1. All STXM experiments should be possible to describe, 2. The set of common scan types should be easy to read, and 3. Saving of all instrument parameters is encouraged. We further discuss the philosophy behind some of the choices made in defining the NXstxm format. [ABSTRACT FROM AUTHOR]

We present a scanning transmission x-ray microscope (STXM) built on top of our existing modular platform for high resolution imaging experiments. This platform consists of up to three separate vacuum chambers and custom designed piezo stages. These piezo stages are able to move precisely in x-, y- and z-direction, this makes it possible to adjust the components for different imaging modes. During recent experiments the endstation was operated mainly as a transmission x-ray microscope (TXM) [1,2]. [ABSTRACT FROM AUTHOR]

A whole A549 cell and isolated nuclei of HeLa S3 cells in the apoptotic process were investigated by using a scanning transmission X-ray microscope (STXM) in the UVSOR Synchrotron (Okazaki, Japan). Near edge X-ray absorption fine structures (NEXAFS) of DNA and histone in the N K-edge region were measured as reference and their distribution in the nuclei was determined by using these reference spectra. The four stages of the apoptosis were successfully distinguished. [ABSTRACT FROM AUTHOR]

We report the design and performance of a compact scanning transmission X-ray microscope developed at the Photon Factory. Piezo-driven linear stages are used as coarse stages of the microscope to realize excellent compactness, mobility, and vibrational and thermal stability. An X-ray beam with an intensity of ~107 photons/s was focused to a diameter of ~40 nm at the sample. At the soft X-ray undulator beamline used with the microscope, a wide range of photon energies (250-1600 eV) is available. The microscope has been used to research energy materials and in environmental sciences. [ABSTRACT FROM AUTHOR]

Pure and 1mol%, 2mol%, 3mol% and 5mol% Gd doped ZnO nanoparticles were synthesized by simple combustion technique and were characterized using X-raydiffraction (XRD), Scanning and Transmission Electron Microscopy (SEM) and Photoluminescence(PL)spectroscopy. Violet to blue emission was observed in doped samples. [ABSTRACT FROM AUTHOR]

The effect of the thermal annealing on silver nanoparticles deposited on silicon surface has been studied. The silver nanoparticles have been deposited by the galvanic displacement reaction. Rapid thermal annealing (RTA) has been performed on the Si substrate, containing the silver nanoparticles. The scanning transmission electron microscopy (STEM), energy dispersive X-ray (EDX) spectroscopy and scanning electron microscopy (SEM) study show that the galvanic displacement reaction and subsequent rapid thermal annealing could lead to well separated and spherical shaped larger silver nanoparticles on silicon substrate. [ABSTRACT FROM AUTHOR]

Nanocomposites of NBR with manganous-tungstate nanoparticles were prepared through vulcanization process. The extent of interaction of nanoparticles with the polymer was studied by FTIR, SEM, XRD, TGA and AC conductivity. FTIR and XRD ascertain the interaction of NBR with MnWO4 nanoparticles. SEM analysis established that the nanopartilces were well dispersed in the macromolecular chain of NBR. The mechanical properties of the nanocomposites were studied as a function of filler loading. The nanocomposites exhibited enhanced thermal stability as seen in TGA. Conductivity and dielectric properties of nanocomposites increase with increase in concentration of MnWO4 nanoparticles (7phr) and thereafter the value decreases. [ABSTRACT FROM AUTHOR]

Tomography is an efficient tool to probe the 3 dimensional (3D) structure of materials. In the laboratory, a device has been developed to perform electron tomography in an environmental scanning electron microscopy (ESEM). The configuration of Scanning Transmission Electron Microscopy (STEM) in Environmental Scanning Electron Microscopy (ESEM) provides a novel approach for the characterization of the 3D structure of materials and optimizes a compromise between the resolution level of a few nm and the large tomogram due to the high thickness of transparency. Moreover, STEM allows the observation in 2D of wet samples in an ESEM by finely controlling the sample temperature and the water pressure of the sample environment. It has been recently demonstrated that it was possible to acquire image series of hydrated objects and thus to attain 3D characterization of wet samples. In order to get reliable and quantitative data, the present study deals with the simulation of electron-matter interactions. From such simulation on the MCM-41 material, we determine the minimum quantity of water layer which can be detected on wet materials. [ABSTRACT FROM AUTHOR]

We investigate the behavior of the Xe in the Si lattice re-growth after the implantation, varying the temperature of the annealing (750-11000C) and the Xe dose. The Xe is implanted alone or with the species generally used to form the junction in VLSI Si devices. The TEM analysis detects 3 types of defect: the stacking faults, the agglomerations of Xe and the EOR defects. Moreover some amorphous areas are left in Si for the lowest thermal budget and the highest dose of Xe. The experimental observations show that: the Xe presence blocks the epitaxial re-growth, the Xe tends to agglomerate, the higher the thermal budget the more Xe exit from the Si and finally the co-implantation increases the defects density. This study reports also results of ab-initio calculations that are able to highlight some trends of the Xe agglomerate in term of their stability and configuration. [ABSTRACT FROM AUTHOR]

Individual particles within bimetallic nanoparticle populations are not always identical, limiting the usefulness of bulk analysis techniques such as EXAFS. The scanning transmission electron microscope (STEM) is the only instrument able to characterize supported nanoparticle populations on a particle-by-particle basis. Quantitative elemental analyses of sub-5-nm particles reveal phase separations among particles and surface segregation within particles. This knowledge can lead to improvements in bimetallic catalysts. Advanced STEMs with field-emission guns, aberration-corrected optics, and efficient signal detection systems allow analysis of sub-nanometer particles. [ABSTRACT FROM AUTHOR]

A vertical nanowire tunnel field effect transistor (TFET) and a bit cost scalable (BICS) flash memory are characterized by electron tomography. The optimum measurement conditions are investigated by comparison of the 3D reconstructions obtained with different specimen geometries and different image modes. The few nm thick layers of both devices are clearly observed on the 3D reconstructions, showing the high resolution of this technique and its importance for the analysis of nanodevices. [ABSTRACT FROM AUTHOR]

A circular type multilayer Laue lens (MLL) has been designed and fabricated. A graded-thickness multilayer was deposited on a tapered wire core by using a magnetron sputtering system. A combination of MoSi2 and Si was chosen as the multilayer materials owing to its superior properties of high diffraction efficiency and relatively sharp interfaces between layers. Optical properties of the circular type MLL were measured at BL24XU of SPring-8 with 20-keV x-rays. It was confirmed that only the +first-order diffraction was focused in the focal point owing to the wedged zone structure. Measured +first-order diffraction efficiency of the multilayer part was as high as 52%. Applying the circular type MLL to scanning transmission microscopy, a 50-nm line and space of a test chart was resolved. [ABSTRACT FROM AUTHOR]

We have modified scanning transmission x-ray microscopes (STXM) at the Canadian Light Source and the Advanced Light Source with total electron yield (TEY) detection (TEY-STXM). This provides improved surface-sensitive detection, simultaneous with existing bulk-sensitive transmission detection in the STXM microscopes. We have explored sample-current and channeltron-based electron yield detection. Both approaches provide improved surface sensitive imaging and spectroscopy, although channeltron-based detection is superior. TEY-STXM provides surface sensitive imaging of ultrathin films such as phase-separated Langmuir-Blodgett monolayer films, as well as differentiation of surface and bulk oxides of patterned metallic thin films. This paper will outline the experimental challenges of this method and the opportunities for correlative surface and bulk measurements of complex samples. [ABSTRACT FROM AUTHOR]

We demonstrate the highest spatial resolution reported in scanning transmission x-ray microscopy to date. For the first time in x-ray microscopy, features below 10 nm in width were resolved in the soft x-ray regime (1.2 keV) and 20-nm lines and spaces were visible at multi-keV photon energies (6.2 keV). These achievements were accomplished using zone-doubled Fresnel zone plates. These lenses were fabricated by combining electron-beam lithography and atomic layer deposition of iridium. Diffraction efficiencies up to 8% were measured for zone-doubled Fresnel zone plates with an outermost zone width of 25 nm at 6.2-keV photon energy. [ABSTRACT FROM AUTHOR]

A multilayer Laue lens (MLL) made from MoSi2/Si has been fabricated aiming at a sub-10-nm spatial resolution for hard x-ray microscopy. A multilayer of 1000 alternating MoSi2 and Si layers with a layer thickness gradually increasing from 5 nm to 316 nm according to the Fresnel lens structure was deposited on a silicon substrate using DC magnetron sputtering, and then the substrate was diced, polished and thinned. The multilayer total thickness was about 10 μm. Optical properties were measured at the SPring-8 beamline BL24XU using 20-keV x-rays. While observing changes in far-field diffraction patterns by changing the tilt angle of the MLL, a dynamical diffraction effect of the MLL was visually confirmed. The achieved line focusing size was 13.1 nm, which is the best ever reported by using an MLL. The maximum local diffraction efficiency was measured to be 62%. Further, two MLLs were arranged in the KB configuration and applied to scanning transmission microscopy. [ABSTRACT FROM AUTHOR]