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Secondary ion mass spectrometry

Ting Wu, Rupam Mukherjee, Olga S Ovchinnikova, Liam Collins, Mahshid Ahmadi, Wei Lu, Nam-Goo Kang, Jimmy W Mays, Stephen Jesse, David Mandrus, Bin Hu
Hybrid perovskites, as emerging multifunctional semiconductors, have demonstrated dual electronic/ionic conduction properties. Here we report a metal/ion interaction induced p-i-n junction across slightly n-type doped MAPbI3 single crystals with Au/MAPbI3/Ag configuration based on interface depend-ent Seebeck effect, Hall effect and time-of-flight secondary ion mass spectrometry analysis. The organic cations (MA(+)) are shown to interact with Au atoms, forming positively charged coordination complexes at Au/MAPbI3 interface, while iodine anions (I(-)) can react with Ag contacts, leading to interfacial ionic polarization...
November 15, 2017: Journal of the American Chemical Society
Melissa K Passarelli, Alexander Pirkl, Rudolf Moellers, Dmitry Grinfeld, Felix Kollmer, Rasmus Havelund, Carla F Newman, Peter S Marshall, Henrik Arlinghaus, Morgan R Alexander, Andy West, Stevan Horning, Ewald Niehuis, Alexander Makarov, Colin T Dollery, Ian S Gilmore
We report the development of a 3D OrbiSIMS instrument for label-free biomedical imaging. It combines the high spatial resolution of secondary ion mass spectrometry (SIMS; under 200 nm for inorganic species and under 2 μm for biomolecules) with the high mass-resolving power of an Orbitrap (>240,000 at m/z 200). This allows exogenous and endogenous metabolites to be visualized in 3D with subcellular resolution. We imaged the distribution of neurotransmitters-gamma-aminobutyric acid, dopamine and serotonin-with high spectroscopic confidence in the mouse hippocampus...
November 13, 2017: Nature Methods
Purva Kulkarni, Mina Dost, Özgül Demir Bulut, Alexander Welle, Sebastian Böcker, Wilhelm Boland, Aleš Svatoš
Spatially resolved analysis of a multitude of compound classes has become feasible with the rapid advancement in mass spectrometry imaging strategies. In this study, we present a protocol that combines high lateral resolution TOF-SIMS imaging with a multivariate data analysis (MVA) approach to probe the complex leaf surface chemistry of Populus trichocarpa. Here, epicuticular waxes (EWs) found on the adaxial leaf surface of Populus trichocarpa were blotted on silicon wafers and imaged using time-of-flight secondary ion mass spectrometry (TOF-SIMS) at 10 μm and 1 μm lateral resolution...
November 8, 2017: Plant Journal: for Cell and Molecular Biology
Paweł Piotr Michałowski, Iwona Pasternak, Włodzimierz Strupiński
In this study, we demonstrate that graphene grown on Ge does not contain any copper contamination, and identify some of the errors affecting the accuracy of commonly used measurement methods. Indeed, one of these, the Secondary Ion Mass Spectrometry (SIMS) technique, reveals copper contamination in Ge-based graphene but does not take into account the effect of the presence of the graphene layer. We have shown that this layer increases negative ionization significantly, and thus yields false results, but also that the graphene enhances, by an order of two, the magnitude of the intensity of SIMS signals when compared with a similar graphene-free sample, enabling much better detection limits...
November 8, 2017: Nanotechnology
Krešimir Salamon, Maja Buljan, Iva Šarić, Mladen Petravić, Sigrid Bernstorff
Tantalum nitride nanoparticles (NPs) and cubic bixbyite-type Ta2N3 nanocrystals (NCs) were grown in (Ta-N+Al2O3)/Al2O3 periodic multilayers (MLs) after thermal treatment. The MLs were prepared by magnetron deposition at room temperature and characterized using grazing incidence small-angle X-ray scattering (GISAXS), X-ray reflectivity (XRR), grazing incidence X-ray diffraction (GIXRD), secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS). We found amorphous tantalum nitride NPs at 600-800 °C, with a high degree of ordering along the surface normal and short-range ordering within the layers containing tantalum (metallic layers)...
2017: Beilstein Journal of Nanotechnology
Cédric Hubas, Dominique Boeuf, Bruno Jesus, Najet Thiney, Yann Bozec, Christian Jeanthon
Mass blooms of purple sulfur bacteria growing seasonally on green stranded macroalgae have a major impact on the microbial composition and functionality of intertidal mats. To explore the active anoxygenic phototrophic community in purple bacterial mats from the Roscoff Aber Bay (Brittany, France), we conducted a combined approach including molecular and high-resolution secondary ion mass spectrometry (NanoSIMS) analyses. To investigate the dynamics of carbon and nitrogen assimilation activities, NanoSIMS was coupled with a stable isotope probing (SIP) experiment and a compound specific isotope analysis (CSIA) of fatty acid methyl ester (FAME)...
2017: Frontiers in Microbiology
Choon-Sang Park, Eun Young Jung, Dong Ha Kim, Do Yeob Kim, Hyung-Kun Lee, Bhum Jae Shin, Dong Ho Lee, Heung-Sik Tae
Although polymerized aniline (polyaniline, PANI) with and without iodine (I₂) doping has already been extensively studied, little work has been done on the synthesis of PANI films using atmospheric pressure plasma (APP) deposition. Therefore, this study characterized pure and I₂-doped PANI films synthesized using an advanced APP polymerization system. The I₂ doping was conducted ex-situ and using an I₂ chamber method following the APP deposition. The pure and I₂-doped PANI films were structurally analyzed using field emission scanning electron microscope (FE-SEM), atomic force microscope (AFM), X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and time of flight secondary ion mass spectrometry (ToF-SIMS) studies...
November 6, 2017: Materials
Antonio J Martín, Sharon Mitchell, Olivier Scholder, René Verel, Roland Hauert, Laetitia Bernard, Christopher Jensen, Meinhard Schwefer, Javier Pérez-Ramírez
An improved understanding of the nature and distribution of boron and cesium species in BCsX zeolites is prerequisite to guide future developments in the environmentally attractive yet challenging production of styrene via the side-chain alkylation of toluene with methanol. Here, standard characterization and catalytic tests are complemented by integrated visualization through time-of-flight secondary ion mass spectrometry and energy-dispersive X-ray spectroscopy and detailed assessment by 133Cs and 11B nuclear magnetic resonance spectroscopy, to correlate the properties and performance during the successive ion exchange and impregnation steps in the preparation of both powders and millimeter-sized granules...
November 7, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
Paweł Piotr Michałowski, Piotr Gutowski, Dorota Pierścińska, Kamil Pierściński, Maciej Bugajski, Włodek Strupiński
Secondary ion mass spectrometry is applied to the depth profiling of the superlattice active region of lattice matched (∼9.2 μm) Al0.48In0.52As/In0.53Ga0.47As/InP quantum cascade lasers. The developed measurement procedure is capable of characterizing the quality of each individual layer in the superlattice region, including layers as thin as 0.7 nm. The oxygen level for AlInAs and InGaAs layers is in the range of 1-3 × 10(17) atms per cm(3) and below the detection limit (∼1 × 10(16) atms per cm(3)), respectively...
November 16, 2017: Nanoscale
Yanwei Lum, Joel W Ager
Oxide-derived (OD) Cu catalysts have high selectivity towards the formation of multi-carbon products (C2/C3) for aqueous electrochemical CO2 reduction (CO2R). It has been proposed that a large fraction of the initial oxide can be surprisingly resistant to reduction and that these residual oxides play a crucial role in promoting the formation of C2/C3 products. We investigate the stability of residual oxides by synthesizing 18O enriched OD Cu catalysts and testing them for CO2R. These catalysts maintain a high selectivity towards C2/C3 products (~60%) for up to 5h in 0...
November 7, 2017: Angewandte Chemie
Sheng Liu, Hong Zhong, Guangyi Liu, Zhenghe Xu
HYPOTHESIS: Hydroxamate and sulfhydryl surfactants are effective collectors for flotation of copper minerals. The combination application of hydroxamate and sulfhydryl collectors has been proved to be an effective approach for improving the flotation recovery of non-sulfide copper minerals. A surfactant owing both hydroxamate and dithiocarbamate groups might exhibit strong affinity to non-sulfide copper minerals through double sites adsorption, rendering an enhanced hydrophobization to non-sulfide copper minerals flotation...
October 17, 2017: Journal of Colloid and Interface Science
N Desbenoit, A Walch, B Spengler, A Brunelle, A Römpp
RATIONALE: Mass spectrometry imaging (MSI) is a powerful tool for mapping the surface of a sample. Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) and Atmospheric Pressure Matrix-Assisted Laser Desorption/Ionization (AP-MALDI) offer complementary capabilities. Here, we present a workflow to apply both techniques to a single tissue section and combine the resulting data on the example of human colon cancer tissue. METHODS: Following cryo-sectioning, images were acquired using the high spatial resolution (1 μm pixel size) provided by TOF-SIMS...
November 3, 2017: Rapid Communications in Mass Spectrometry: RCM
Qi Li, Huihui Du, Wenli Chen, Jialong Hao, Qiaoyun Huang, Peng Cai, Xionghan Feng
Soil aggregates are often considered the basic structural elements of soils. Aggregates of different size vary in their ability to retain or transfer heavy metals in the environment. Here, after incubation of a sieved (<2 mm) topsoil with copper, bulk soil was separated into four aggregate-size fractions and their adsorption characteristics for Cu were determined. By combining nano-scale secondary ion mass spectrometry and C-1s Near Edge X-ray Absorption Fine Structure Spectroscopy, we found that copper tends to bind onto organic matter in the <2 μm and 20-63 μm aggregates...
November 2, 2017: Environmental Pollution
F Pax C Blamey, Brigid A McKenna, Cui Li, Miaomiao Cheng, Caixian Tang, Haibo Jiang, Daryl L Howard, David J Paterson, Peter Kappen, Peng Wang, Neal W Menzies, Peter M Kopittke
Soil acidity and waterlogging increase manganese (Mn) in leaf tissues to potentially toxic concentrations, an effect reportedly alleviated by increased silicon (Si) and phosphorus (P) supply. Effects of Si and P on Mn toxicity were studied in four plant species using synchrotron-based micro X-ray fluorescence (μ-XRF) and nanoscale secondary ion mass spectrometry (NanoSIMS) to determine Mn distribution in leaf tissues and using synchrotron-based X-ray absorption spectroscopy (XAS) to measure Mn speciation in leaves, stems and roots...
November 1, 2017: New Phytologist
Per Malmberg, Narmin Bigdeli, Jens Jensen, Håkan Nygren
The bone material interface has been an area of intense study over many decades, where studies of the healing process ranging from simple mineral deposition in vitro to actual healing in vivo have given important clues to the importance of calcium minerals in the bone/implant interface. Here, the authors use a combination of in vitro cell culture methods and in vivo implantation to study how the role of the spontaneously formed hydroxyapatite layer on Ti-implants for the in vivo-healing into the bone tissue of rat tibia...
October 27, 2017: Biointerphases
Elizabeth Trembath-Reichert, Yuki Morono, Akira Ijiri, Tatsuhiko Hoshino, Katherine S Dawson, Fumio Inagaki, Victoria J Orphan
The past decade of scientific ocean drilling has revealed seemingly ubiquitous, slow-growing microbial life within a range of deep biosphere habitats. Integrated Ocean Drilling Program Expedition 337 expanded these studies by successfully coring Miocene-aged coal beds 2 km below the seafloor hypothesized to be "hot spots" for microbial life. To characterize the activity of coal-associated microorganisms from this site, a series of stable isotope probing (SIP) experiments were conducted using intact pieces of coal and overlying shale incubated at in situ temperatures (45 °C)...
October 31, 2017: Proceedings of the National Academy of Sciences of the United States of America
Martin Lorenz Eisinger, Aline Ricarda Dörrbaum, Hartmut Michel, Etana Padan, Julian David Langer
Na(+)/H(+) antiporters comprise a family of membrane proteins evolutionarily conserved in all kingdoms of life and play an essential role in cellular ion homeostasis. The NhaA crystal structure of Escherichia coli has become the paradigm for this class of secondary active transporters. However, structural data are only available at low pH, where NhaA is inactive. Here, we adapted hydrogen/deuterium-exchange mass spectrometry (HDX-MS) to analyze conformational changes in NhaA upon Li(+) binding at physiological pH...
October 31, 2017: Proceedings of the National Academy of Sciences of the United States of America
Lin Du, April L Risinger, Carter A Mitchell, Jianlan You, Blake W Stamps, Ning Pan, Jarrod B King, Jean C Bopassa, Susan I V Judge, Zhibo Yang, Bradley S Stevenson, Robert H Cichewicz
Mass-spectrometry-based metabolomics and molecular phylogeny data were used to identify a metabolically prolific strain of Tolypocladium that was obtained from a deep-water Great Lakes sediment sample. An investigation of the isolate's secondary metabolome resulted in the purification of a 22-mer peptaibol, gichigamin A (1). This peptidic natural product exhibited an amino acid sequence including several β-alanines that occurred in a repeating ααβ motif, causing the compound to adopt a unique right-handed 311 helical structure...
October 24, 2017: Proceedings of the National Academy of Sciences of the United States of America
Yuanyuan Shi, Ruoqi Wang, Xiaoyu Zhu, Dongge Xu, Wenyuan Liu, Feng Feng
Profiling chemical components in herbs by mass spectrometry is a challenging work because of the lack of standard compounds, especially for position isomers. This paper provides a strategy based on a self-feedback network of mass spectra (MS) data to identify chemical constituents in herbs by liquid chromatography-quadrupole-time of flight mass spectrometry without compound standards. Components sharing same skeleton were screened and all ions were classified into a database. All candidates were connected by the selected bridging ions to establish a primary MS network...
October 23, 2017: Scientific Reports
Ryo Sekine, Katie L Moore, Marianne Matzke, Pascal Vallotton, Haibo Jiang, Gareth M Hughes, Jason K Kirby, Erica Donner, Chris R M Grovenor, Claus Svendsen, Enzo Lombi
Increasing consumer use of engineered nanomaterials has led to significantly increased efforts to understand their potential impact on the environment and living organisms. Currently, no individual technique can provide all the necessary information such as their size, distribution, and chemistry in complex biological systems. Consequently, there is a need to develop complementary instrumental imaging approaches that provide enhanced understanding of these "bio-nano" interactions to overcome the limitations of individual techniques...
November 13, 2017: ACS Nano
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