WorldWideScience

Sample records for angle neutron scattering

  1. Neutron small angle scattering

    International Nuclear Information System (INIS)

    Ibel, K.

    1975-01-01

    The neutron small-angle scattering system at the High-Flux Reactor in Grenoble consists of three major parts: the supply of cold neutrons via bent neutron guides; the small angle camera D11; and the data handling facilities. The camera D11 has an overall length of 80 m. The effective length of the camera is variable. The length of the collimator before the fixed sample position can be reduced by movable neutron guides; the secondary flight path of 40 m full length contains detector sites in various positions. Thus, a large domain of momentum transfers can be exploited. Scattering angles between 5.10 -4 and 0.5 rad and neutron wavelengths from 0.2 to 2.0 nm are available with the same instrument and the same relative resolution. A large-area position-sensitive detector is used which allows simultaneous recording of intensities scattered into different angles; it is a multiwire proportional chamber. 3808 elements of 1 cm 2 are arranged in a two-dimensional matrix. Future development comprises an increase of the limit in the count rate due to the electronic interface between the detector and on-line computer, actually at 5.10 4 per sec. by one order of magnitude

  2. Small angle neutron scattering

    International Nuclear Information System (INIS)

    Gupta, Sanjay

    1982-01-01

    The technique of small angle neutron scattering was first used in Germany less than two decades ago. Since then it has developed very rapidly, and today it is regarded as one of the most powerful techniques in materials, chemical and biological research. During the last decade the combination of high flux reactors and sophisticated instrumentation has revolutionized the technique. This paper endeavours to present a brief but comprehensive review of small angle scattering of neutrons and its applications in solid state research. The domain in which small angle neutron scattering is particularly useful is delineated and some of the methods used in the analysis of data are discussed with special emphasis on recent developments. Typical small angle neutron scattering cameras are described. Finally some experimental results on heterogeneities in metallic systems (both static and dynamic studies), radiation damage in materials, superconductivity, magnetic materials and the technologically very important area of non-destructive testing are reviewed in order to illustrate the wide range of applicability of this technique to problems in solid state research. (author)

  3. Small angle neutron scattering

    International Nuclear Information System (INIS)

    Dasannacharya, B.A.; Goyal, P.S.

    1997-01-01

    Small angle neutron scattering (SANS) is one of the most popular neutron scattering technique both for the basic research and as a tool in the hands of applied scientist. SANS is used for studying the structure of a material on a length scale of 10 - 1000 A. SANS is a diffraction experiment that involves scattering of a monocromatic beam of neutrons in order to obtain structural information about macromolecules and heterogeneities. This paper will discuss the design of SANS spectrometers with a special emphasis on the instruments which are better suited for medium flux reactors. The design of several different types of SANS spectrometers will be given. The optimization procedures and appropriate modifications to suit the budget and the space will be discussed. As an example, the design of a SANS spectrometer at CIRUS reactor Trombay will be given. (author)

  4. Small angle neutron scattering

    Directory of Open Access Journals (Sweden)

    Cousin Fabrice

    2015-01-01

    Full Text Available Small Angle Neutron Scattering (SANS is a technique that enables to probe the 3-D structure of materials on a typical size range lying from ∼ 1 nm up to ∼ a few 100 nm, the obtained information being statistically averaged on a sample whose volume is ∼ 1 cm3. This very rich technique enables to make a full structural characterization of a given object of nanometric dimensions (radius of gyration, shape, volume or mass, fractal dimension, specific area… through the determination of the form factor as well as the determination of the way objects are organized within in a continuous media, and therefore to describe interactions between them, through the determination of the structure factor. The specific properties of neutrons (possibility of tuning the scattering intensity by using the isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons make it particularly interesting in the fields of soft matter, biophysics, magnetic materials and metallurgy. In particular, the contrast variation methods allow to extract some informations that cannot be obtained by any other experimental techniques. This course is divided in two parts. The first one is devoted to the description of the principle of SANS: basics (formalism, coherent scattering/incoherent scattering, notion of elementary scatterer, form factor analysis (I(q→0, Guinier regime, intermediate regime, Porod regime, polydisperse system, structure factor analysis (2nd Virial coefficient, integral equations, characterization of aggregates, and contrast variation methods (how to create contrast in an homogeneous system, matching in ternary systems, extrapolation to zero concentration, Zero Averaged Contrast. It is illustrated by some representative examples. The second one describes the experimental aspects of SANS to guide user in its future experiments: description of SANS spectrometer, resolution of the spectrometer, optimization of

  5. SANS-1: Small angle neutron scattering

    Directory of Open Access Journals (Sweden)

    André Heinemann

    2015-08-01

    Full Text Available The new small angle scattering instrument SANS-1, jointly operated by the Technische Universität München and GEMS, Helmholtz-Zentrum Geesthacht, has completed commissioning and is in regular user service (Gilles et al., 2006. SANS-1 is located at the end of neutron guide NL4a in the Neutron Guide Hall West.

  6. SANS-1: Small angle neutron scattering

    OpenAIRE

    Heinemann, André; Mühlbauer, Sebastian

    2015-01-01

    The new small angle scattering instrument SANS-1, jointly operated by the Technische Universität München and GEMS, Helmholtz-Zentrum Geesthacht, has completed commissioning and is in regular user service (Gilles et al., 2006). SANS-1 is located at the end of neutron guide NL4a in the Neutron Guide Hall West.

  7. A small-angle neutron scattering study

    Indian Academy of Sciences (India)

    400Da [9]. Low-angle X-ray scattering [10] and neutron scattering [11] also in- dicated serum albumin to be a prolate ellipsoid. However, studies using 1H NMR indicated that a prolate structure was unlikely; rather a heart-shaped structure was proposed [12]. The shape of albumin reveals a heart-shaped molecule that can.

  8. Small-angle neutron-scattering experiments

    International Nuclear Information System (INIS)

    Hardy, A.D.; Thomas, M.W.; Rouse, K.D.

    1981-04-01

    A brief introduction to the technique of small-angle neutron scattering is given. The layout and operation of the small-angle scattering spectrometer, mounted on the AERE PLUTO reactor, is also described. Results obtained using the spectrometer are presented for three materials (doped uranium dioxide, Magnox cladding and nitrided steel) of interest to Springfields Nuclear Power Development Laboratories. The results obtained are discussed in relation to other known data for these materials. (author)

  9. Experimental technique of small angle neutron scattering

    International Nuclear Information System (INIS)

    Xia Qingzhong; Chen Bo

    2006-03-01

    The main parts of Small Angle Neutron Scattering (SANS) spectrometer, and their function and different parameters are introduced from experimental aspect. Detailed information is also introduced for SANS spectrometer 'Membrana-2'. Based on practical experiments, the fundamental requirements and working condition for SANS experiments, including sample preparation, detector calibration, standard sample selection and data preliminary process are described. (authors)

  10. A small angle neutron scattering study

    Indian Academy of Sciences (India)

    Nanocrystalline nickel oxide powders were calcined at 300, 600 and 900°C and pore structure evolution was followed by small angle neutron scattering (SANS). Pore size distributions at two widely separated size ranges have been revealed. Shrinkage of larger-sized pore with reduction in polydispersity has been observed ...

  11. A small-angle neutron scattering investigation

    Indian Academy of Sciences (India)

    Hence, the steel is used in aircraft, nuclear reactor, petrochemical plants and many other industries. However, presence of carbide formers such as Mo and Cr war- rants the possibility of carbide precipitates in the structure and in turn affects the mechanical properties. Small-angle neutron scattering (SANS) is an important ...

  12. Neutron imaging and small angle neutron scattering instruments at KUR

    International Nuclear Information System (INIS)

    Saito, Yasushi; Oba, Yojiro; Hino, Masahiro

    2015-01-01

    We review the neutron imaging (NI) and small-angle neutron scattering (SANS) instruments at KUR, Kumatori, Osaka, Japan. There are two NI and one SANS instruments. The both instruments are compact and used flexibly. Some challenging experiments taking advantage of low neutron fluence are described. The feature of KUR is also described briefly. (author)

  13. Small angle neutron scattering from glassy SiO2

    International Nuclear Information System (INIS)

    Spooner, S.; Hastings, J.B.

    1976-01-01

    The present investigation of neutron scattering from glassy silica was undertaken to resolve whether the small angle scattering observed by Renninger and Uhlmann could also be seen in the bulk samples typically used in neutron-scattering experiments. Within the rather large error bars of this experiment no small angle scattering increase at small angles could be seen. (Auth.)

  14. Neutron elastic scattering at very small angles

    CERN Multimedia

    2002-01-01

    This experiment will measure neutron-proton elastic scattering at very small angles and hence very small four-momentum transfer, |t|. The range of |t| depends on the incident neutron momentum of the events but the geometrical acceptance will cover the angular range 0.025 < $\\Theta_{lab}$ < 1.9 mrad. The higher figure could be extended to 8.4 mrad by changing the geometry of the experiment in a later phase. \\\\ \\\\ The neutron beam will be highly collimated and will be derived from a 400 GeV external proton beam of up to $4 \\times 10^{10}$ protons per pulse in the SPS North Area Hall 1. The hydrogen target will be gaseous, operating at 40 atm. pressure and acts as a multiwire proportional chamber to detect the recoil protons. The forward neutron will be detected and located by interaction in a neutron vertex detector and its energy measured by a conventional steel plate calorimeter. \\\\ \\\\ The experiment will cover the angular region of nucleon-nucleon scattering which is dominated by Coulomb scattering ...

  15. Phase sensitive small angle neutron scattering

    Science.gov (United States)

    Brok, Erik; Majkrzak, Charles F.; Krycka, Kathryn

    It is a well-known problem that information about the scattered wave is lost in scattering experiments because the measured quantity is the modulus squared of the complex wave function. This ''phase problem'' leads to ambiguity in determining the physical properties of the scattering sample. Small angle neutron scattering (SANS) is a useful technique for determining the structure of biomolecules, in particular proteins that cannot be crystallized and studied with x-ray crystallography. However, because the biomolecules are usually suspended in a liquid the observed scattering is an average of all possible orientations, making it difficult to obtain three dimensional structural information. In a proposed method polarized SANS and magnetic nanoparticle references attached to the sample molecules is used to obtain phase sensitive structural information and simultaneously circumvent the problem of orientational averaging (Majkrzak et al. J. Appl. Cryst. 47, 2014) If realized and perfected the technique is very promising for unambiguous determination of the three dimensional structure of biomolecules. We demonstrate the principles of our method and show the first experimental data obtained on a simple test system consisting of core shell magnetic nanoparticles.

  16. Small-angle neutron scattering technique in liquid crystal studies

    International Nuclear Information System (INIS)

    Shahidan Radiman

    2005-01-01

    The following topics discussed: general principles of SAS (Small-angle Neutron Scattering), liquid crystals, nanoparticle templating on liquid crystals, examples of SAS results, prospects of this studies

  17. Small angle polarised neutron scattering investigation of magnetic nanoparticles

    International Nuclear Information System (INIS)

    Bergenti, I.; Deriu, A.; Savini, L.; Bonetti, E.; Spizzo, F.; Hoell, H.

    2003-01-01

    Small angle scattering of polarised neutron (SANSPOL) is a powerful technique for the determination of magnetisation, density and compositional profiles of nanostructured particles. We present here some examples of the magnetic profile determination using the SANSPOL technique and we discuss in detail its advantage with respect to the conventional small angle neutron scattering approach

  18. Small angle neutron scattering and small angle X-ray scattering ...

    Indian Academy of Sciences (India)

    Abstract. The morphology of carbon nanofoam samples comprising platinum nanopar- ticles dispersed in the matrix was characterized by small angle neutron scattering (SANS) and small angle X-ray scattering (SAXS) techniques. Results show that the structure of pores of carbon matrix exhibits a mass (pore) fractal nature ...

  19. Small angle neutron scattering and small angle X-ray scattering ...

    Indian Academy of Sciences (India)

    Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India. *Corresponding author ... ticles dispersed in the matrix was characterized by small angle neutron scattering (SANS) and small angle X-ray ... for scattering from rough pore–mass interfaces, α > 3 and the (surface) fractal dimension Ds = 6 ...

  20. Small angle neutron scattering and small angle X-ray scattering ...

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... Small angle neutron scattering and small angle X-ray scattering studies of platinum-loaded carbon foams. P U Sastry V K Aswal A G Wagh ... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science (IWCCMP-2015). Posted on November ...

  1. Small angle neutron scattering from nanometer grain sized materials

    Science.gov (United States)

    Epperson, J. E.; Siegel, R. W.

    1991-11-01

    Small angle neutron scattering has been utilized, along with a number of complementary characterization methods suitable to the nanometer size scale, to investigate the structures of cluster-assembled nanophase materials. Results of these investigations are described and problems and opportunities in using small angle scattering for elucidating nanostructures are discussed.

  2. Small Angle Scattering in Neutron Imaging—A Review

    Directory of Open Access Journals (Sweden)

    Markus Strobl

    2017-12-01

    Full Text Available Conventional neutron imaging utilizes the beam attenuation caused by scattering and absorption through the materials constituting an object in order to investigate its macroscopic inner structure. Small angle scattering has basically no impact on such images under the geometrical conditions applied. Nevertheless, in recent years different experimental methods have been developed in neutron imaging, which enable to not only generate contrast based on neutrons scattered to very small angles, but to map and quantify small angle scattering with the spatial resolution of neutron imaging. This enables neutron imaging to access length scales which are not directly resolved in real space and to investigate bulk structures and processes spanning multiple length scales from centimeters to tens of nanometers.

  3. Small-angle neutron scattering studies of sodium butyl benzene

    Indian Academy of Sciences (India)

    Na-NBBS), in aqueous solutions is investigated by small-angle neutron scattering (SANS). Nearly ellipsoidal aggregates of Na-NBBS at concentrations well above its minimum hydrotrope concentration were detected by SANS. The hydrotrope ...

  4. Small-angle neutron scattering studies of sodium butyl benzene ...

    Indian Academy of Sciences (India)

    Na-NBBS), in aqueous solutions is investigated by small-angle neutron scattering (SANS). Nearly ellipsoidal aggregates of Na-NBBS at concentrations well above its minimum hydrotrope concentration were detected by SANS. The hydrotrope ...

  5. Multiple small-angle neutron scattering studies of anisotropic materials

    CERN Document Server

    Allen, A J; Long, G G; Ilavsky, J

    2002-01-01

    Building on previous work that considered spherical scatterers and randomly oriented spheroidal scatterers, we describe a multiple small-angle neutron scattering (MSANS) analysis for nonrandomly oriented spheroids. We illustrate this with studies of the multi-component void morphologies found in plasma-spray thermal barrier coatings. (orig.)

  6. Small angle neutron scattering in surface-active agents mixtures

    Science.gov (United States)

    Bulavin, L. A.; Garamus, V. M.; Ostanevich, Yu. M.

    The method of study of micelle structure by small angle neutron scattering is studied. The determination of maximum size, radius of gyration, average scattering density of micelles is presented. The way of study of distribution of scattering density in micelle is described. The problem of micelles interaction is discussed.

  7. Investigation of ferromagnetic domain structures by neutron small angle scattering

    International Nuclear Information System (INIS)

    Schild, L.

    1984-01-01

    The magnetic small angle scattering of thermal neutrons caused by magnetic refraction at domain walls of ferromagnetic materials without texture has been investigated. Experiments on Fe-Si alloys with a twin crystal diffractometer were carried out. It is shown that the mean extension of magnetic basic units (domains as well as parallel wall systems) can be determined. A comparison of grain sizes determined metallographically with domain sizes obtained by neutron small-angle scattering has shown that neither mean grain size nor domain size can be assessed by small-angle scattering experiments

  8. Neutron small angle scattering of irradiated aluminium-silicon alloys

    International Nuclear Information System (INIS)

    Kostorz, G.

    1976-01-01

    Technically pure aluminium and aluminium-silicon alloys (0.43, 0.83 and 1.2% Si, also containing 0.11 to 0.14 at. % Fe) were investigated by slow neutron small angle scattering after irradiation with fast neutrons at low temperatures. Different irradiation levels, ageing at room temperature and at 60/70 0 C had no measurable effect upon small angle scattering cross-sections. From the experimental precision upper limit for the amount of Si involved in clustering after irradiation can be given. The observed small angle scattering shows a strong dependence on scattering angles and is attributed to large precipitates of Al 12 Fe 3 Si. A surface layer on the as-received samples is identified as another source of low-intensity small angle scattering. (orig.) [de

  9. Fractal approach in petrology: Combining ultra small angle (USANS), and small angle neutron scattering (SANS)

    International Nuclear Information System (INIS)

    Lo Celso, F.; Triolo, R.; Triolo, F.; Triolo, A.; Lin, J.S.; Lucido, G.

    2000-01-01

    Ultra small angle neutron scattering instruments have recently covered the gap between the size resolution available with conventional intermediate angle neutron scattering and small angle neutron scattering instruments on one side and optical microscopy on the other side. Rocks showing fractal behavior in over two decades of momentum transfer and seven orders of magnitude of intensity are examined and fractal parameters are extracted from the combined USANS and SANS curves

  10. Fractal Approach in Petrology: Combining Ultra-Small Angle (USANS) and Small Angle Neutron Scattering (SANS)

    International Nuclear Information System (INIS)

    LoCelso, F.; Triolo, F.; Triolo, A.; Lin, J.S.; Lucido, G.; Triolo, R.

    1999-01-01

    Ultra small angle neutron scattering instruments have recently covered the gap between the size resolution available with conventional intermediate angle neutron scattering and small angle neutron scattering instruments on one side and optical microscopy on the other side. Rocks showing fractal behavior in over two decades of momentum transfer and seven orders of magnitude of intensity are examined and fractal parameters are extracted from the combined USANS and SANS curves

  11. Small Angle Neutron Scattering instrument at Malaysian TRIGA reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shukri Mohd; Razali Kassim; Zal Uyun Mahmood [Malaysian Inst. for Nuclear Technology Research (MINT), Bangi, Kajang (Malaysia); Shahidan Radiman

    1998-10-01

    The TRIGA MARK II Research reactor at the Malaysian Institute for Nuclear Research (MINT) was commissioned in July 1982. Since then various works have been performed to utilise the neutrons produced from this steady state reactor. One of the project involved the Small Angle Neutron Scattering (SANS). (author)

  12. An introduction to small-angle neutron scattering

    International Nuclear Information System (INIS)

    Windsor, C.G.

    1988-01-01

    Neutron and X-ray small-angle scattering provide, along with electron microscopy and diffraction, the principal techniques for the microscopic characterization of materials. Neutron, X-ray and electron beams each have quite different properties. In fact, each has unique advantages. The penetration of neutrons through most materials is responsible for many applications. The ever-increasing intensity of available X-ray beams is opening new fields. The advantage of electron beams is their ability to work in both real and reciprocal space. The problems of transforming the results of an experiment in reciprocal space to give an interpretation in real space are central to small-angle scattering, and are discussed. Several examples will be given of the successful use of small-angle neutron scattering applied to problems where other techniques have failed to make a decisive contribution. (orig.)

  13. Small Angle Scattering in Neutron Imaging : A Review

    NARCIS (Netherlands)

    Strobl, Markus; Harti, Ralph P.; Grünzweig, Christian; Woracek, Robin; Plomp, J.

    2017-01-01

    Conventional neutron imaging utilizes the beam attenuation caused by scattering and absorption through the materials constituting an object in order to investigate its macroscopic inner structure. Small angle scattering has basically no impact on such images under the geometrical conditions applied.

  14. Multiple magnetic scattering in small-angle neutron scattering of Nd?Fe?B nanocrystalline magnet

    OpenAIRE

    Ueno, Tetsuro; Saito, Kotaro; Yano, Masao; Ito, Masaaki; Shoji, Tetsuya; Sakuma, Noritsugu; Kato, Akira; Manabe, Akira; Hashimoto, Ai; Gilbert, Elliot P.; Keiderling, Uwe; Ono, Kanta

    2016-01-01

    We have investigated the influence of multiple scattering on the magnetic small-angle neutron scattering (SANS) from a Nd?Fe?B nanocrystalline magnet. We performed sample-thickness- and neutron-wavelength-dependent SANS measurements, and observed the scattering vector dependence of the multiple magnetic scattering. It is revealed that significant multiple scattering exists in the magnetic scattering rather than the nuclear scattering of Nd?Fe?B nanocrystalline magnet. It is considered that th...

  15. Small-angle neutron-scattering experiment, (2)

    International Nuclear Information System (INIS)

    Niimura, Nobuo; Kaji, Harumi.

    1983-01-01

    Elementary explanation is given to the experiment on the small angle scattering using neutrons having long wave-length (3-12A), continued from the previous report. Two types of the apparatus for small angle neutron scattering experiment are described. The first is angle dispersion type, which uses the neutron beam from research reactors, and the second is wavelength dispersion type, which uses pulsed cold neutron sources. The principles of these experiments are explained. Especially the wavelength dispersion is described in detail. The apparatus in the booster facility at the Institute for High Energy Physics is shown as an example for the latter type. The two-dimensional position sensitive detector, which is essential for angle dispersion type, is also used for the wavelength dispersion type, and its data processing is also described. In the small angle neutron scattering experiment for the studies on the structure of living body substances, the techniques that should be taken into account in common are discussed; the proportion of D 2 O-H 2 O in solvent, the measurable range of Q, the size of specimens, the correction of incident neutron spectra, and the analysis of measured data. (Asami, T.)

  16. Development of spin echo small angle neutron scattering

    International Nuclear Information System (INIS)

    Bouwman, W.G.; Uca, O.; Van Oossanen, M.; Kraan, W.H.; Rekveldt, M.T.

    1999-01-01

    A novel kind of small angle neutron scattering (SANS) instrument is being built, based on the Larmor precession of polarised neutrons in a magnetic field. A spin echo of the polarised neutrons is used to detect the scattering. The basis of this instrument is a symmetric set-up with a spin flipper in the centre, which creates a spin echo, even with a divergent beam. The precession regions on either side of the spin flipper are shaped such to produce a very sensitive relation between the vertical angle of the neutron path and the total precession angle on one side. Any SANS of a sample placed in the instrument changes the symmetry of the neutron path and therefore decreases the echo. This amounts to measuring only the difference of the incoming and outgoing angle. This gives a huge increase in intensity of the signal with respect to conventional SANS in which both incoming and outgoing angle are defined. Magnetised foils, which rotate the neutron spin between being parallel to the magnetic field and perpendicular to the field are used to start or terminate the precession. With a preliminary set-up the first spin echo SANS signal have been measured. A full correlation function in samples over distances from 5 to 1000 nm is expected to be measured in some minutes. (author)

  17. Birefringent neutron prisms for spin echo scattering angle measurement

    Science.gov (United States)

    Pynn, Roger; Fitzsimmons, M. R.; Lee, W. T.; Stonaha, P.; Shah, V. R.; Washington, A. L.; Kirby, B. J.; Majkrzak, C. F.; Maranville, B. B.

    2009-09-01

    In the first decade of the 19th century, an English chemist, William Wollaston, invented an arrangement of birefringent prisms that splits a beam of light into two spatially separated beams with orthogonal polarizations. We have constructed similar devices for neutrons using triangular cross-section solenoids and employed them for Spin Echo Scattering Angle Measurement (SESAME). A key difference between birefringent neutron prisms and their optical analogues is that it is hard to embed the former in a medium which has absolutely no birefringence because this implies the removal of all magnetic fields. We have overcome this problem by using the symmetry properties of the Wollaston neutron prisms and of the overall spin echo arrangement. These symmetries cause a cancellation of Larmor phase aberrations and provide robust coding of neutron scattering angles with simple equipment.

  18. Small angle neutron scattering of micro- and nanostructured materials

    International Nuclear Information System (INIS)

    Trinker, M.

    2006-05-01

    In this work studies of micro- and nanostructured materials by means of neutron scattering techniques are presented. The first part contains the theory of neutron scattering by structures in condensed matter necessary for the understanding of the experimental results. The method of small angle neutron scattering (SANS) is applied to a sample of highly irradiated SiC/SiCf composite. These materials play an important role in concepts for future fusion reactors. Radiation induced structural changes after high-dose irradiation in the spallation target of the SINQ neutron source, Switzerland, are analyzed. For testing instruments and methods used in ultra-small angle neutron scattering (USANS) artificial microstructured samples fabricated from silicon are particularly suitable. Because of the known structure parameters and the model-like character of such samples the performance of the instruments involved and the models used for interpretation of the scattering data can be tested. The development and fabrication of a series of such silicon gratings at the Center for Micro- and Nanostructures (ZMNS) of the Vienna University of Technology are described. The following USANS measurements at the instrument S18 of the Institute Laue-Langevin, Grenoble, which is run by the Atomic Institute of the Austrian Universities, and the instrument itself are presented. Subsequently the results are compared to those of the newly developed spinecho small angle neutron scattering technique (SESANS) at the Delft University of Technology. The complementarity of both techniques is demonstrated by means of the scattering data obtained from the silicon gratings. A method for the direct reconstruction of one-dimensional scattering length density distributions is applied to the USANS scattering data of the silicon microstructures. The results are compared to those obtained from scanning electron microscopy and the applicability of the method to USANS scattering data for the reconstruction of one

  19. Magnetic nanostructures studied by polarized small angle neutron scattering

    International Nuclear Information System (INIS)

    Wiedenmann, Albrecht; Kammel, Martin; Heinemann, Andre

    2005-01-01

    Small Angle Neutron Scattering using polarised neutrons is introduced as a contrast variation technique for magnetic systems. The potential of this technique is illustrated on diluted Ferrofluids. Composition, magnetization and size distributions of magnetic core-shell composite particles and magnetic aggregates could be precisely evaluated beside non-magnetic micelles and free surfactants of similar sizes. Structure factors have been extracted which revealed a local pseudo-crystalline ordering of the magnetic particles induced by magnetic fields

  20. The National Facility for Small-Angle Neutron Scattering

    International Nuclear Information System (INIS)

    Koehler, W.C.

    1986-01-01

    On this occasion honoring Professor C.G.Shull, the 30-m small-angle neutron scattering (SANS) instrument of the National Center for Small-Angle Scattering Research (NCSASR) will have been in routine user-mode operation for five years. Professor Shull served the Center as chairman of its first Advisory Committee and in that capacity contributed his expertise to the construction phase of the 30-m machine and to the formulation of operating policy. He has had a long and varied interest in the scientific application of small-angle scattering of X-rays and of neutrons. It is a pleasure for me to dedicate this review to him on his 70th birthday. (orig.)

  1. Small angle neutron scattering study of mixed micelles of oppositely ...

    Indian Academy of Sciences (India)

    - methylammonium bromide (DTAB) and sodium dodecyl sulphate (SDS) have been studied using small angle neutron scattering. The concentration of one of the components was kept fixed (0.3 M) and that of another varied in the range 0 to ...

  2. A national facility for small angle neutron scattering

    International Nuclear Information System (INIS)

    Buyers, W.J.L.; Katsaras, J.; Mellors, W.; Potter, M.M.; Powell, B.M.; Rogge, R.B.; Root, J.H.; Tennant, D.C.; Tun, Z.

    1995-01-01

    A world-class small angle neutron scattering (SANS) facility is proposed for Canada. It will provide users from the fields of biology, chemistry, physics, materials science and engineering with a uniquely powerful tool for investigating microstructural properties whose length scales lie in the optical to atomic range. (author). 7 refs

  3. Small angle neutron scattering study of two nonionic surfactants in ...

    Indian Academy of Sciences (India)

    cO Indian Academy of Sciences. Vol. 71, No. 5. — journal of. November 2008 physics pp. 1079–1083. Small angle neutron scattering study of two nonionic surfactants in water micellar solutions. RAJEWSKA ALDONA. Institute of Atomic Energy, 05-400 Swierk-Otwock, Poland. E-mail: aldonar@cyf.gov.pl. Abstract.

  4. Small angle neutron scattering study on the aggregation behaviour ...

    Indian Academy of Sciences (India)

    Small angle neutron scattering (SANS) measurements on aqueous solutions of four polyethylene oxide–polypropylene oxide–polyethylene oxide block copolymers (commercially known as Pluronic®)F88, P85, F127 and P123 in the presence of hydrophobic C14Diol (also known as Surfynol® 104) reveal information on ...

  5. Small angle neutron scattering studies of mixed micelles of sodium

    Indian Academy of Sciences (India)

    The aqueous solutions of sodium cumene sulphonate (NaCS) and its mixtures with each of cetyl trimethylammonium bromide (CTAB) and sodium dodecyl sulphate (SDS) are characterized by small angle neutron scattering (SANS). NaCS when added to CTAB solution leads to the formation of long rod-shaped micelles with ...

  6. Small-angle neutron scattering from colloidal dispersions

    International Nuclear Information System (INIS)

    Ottewill, R.H.

    1991-01-01

    A survey is given of recent work on the use of small-angle neutron scattering to examine colloidal dispersions. Particular attention is given to the determination of particle size and polydispersity, the determination of particle morphology and the behaviour of concentrated colloidal dispersions, both at rest and under the influence of an applied shear field. (orig.)

  7. Small-angle neutron scattering from micellar solutions

    Indian Academy of Sciences (India)

    The structure (shape and size) and the interaction of these aggregates, referred to as micelles, depend on the molecular architecture of the surfactant molecule, presence of additives and the solution conditions such as temperature, concentration etc. This paper gives the usefulness of small-angle neutron scattering to the ...

  8. Temperature dependent small-angle neutron scattering of CTABr ...

    Indian Academy of Sciences (India)

    Atomic Research Centre, Mumbai 400 085, India. cDepartment of Physics, Bhavnagar University, Bhavnagar 364 002, India. E-mail: ruv@bhavuni.edu. Abstract. Small-angle neutron scattering studies have been carried out to check the structural integrity of ... the surface of the micelle. Micellar solution of CTABr is isotropic ...

  9. Small-angle neutron scattering studies on water soluble complexes ...

    Indian Academy of Sciences (India)

    ... by small-angle neutron scattering. SANS data showed a positive indication of the formation of RCP-SDS complexes. Even though the complete structure of the polyion complexes could not be ascertained, the results obtained give us the information on the local structure in these polymer-surfactant systems. The data were ...

  10. Characterization of alumina using small angle neutron scattering (SANS)

    International Nuclear Information System (INIS)

    Megat Harun Al Rashidn Megat Ahmad; Abdul Aziz Mohamed; Azmi Ibrahim; Che Seman Mahmood; Edy Giri Rachman Putra; Muhammad Rawi Muhammad Zin; Razali Kassim; Rafhayudi Jamro

    2007-01-01

    Alumina powder was synthesized from an aluminium precursor and studied using small angle neutron scattering (SANS) technique and complemented with transmission electron microscope (TEM). XRD measurement confirmed that the alumina produced was high purity and highly crystalline αphase. SANS examination indicates the formation of mass fractals microstructures with fractal dimension of about 2.8 on the alumina powder. (Author)

  11. Temperature dependent small-angle neutron scattering of CTABr ...

    Indian Academy of Sciences (India)

    Micelles are aggregates of surfactant molecules and these aggregates are usually formed in different shapes of spherical, cylindrical, ellipsoidal, disc-like etc. The size and shapes of these micelles are studied using small-angle neutron scattering (SANS) [2]. A preparation of stable emulsion of magnetic fluid with micelles ...

  12. Small-angle neutron scattering studies of nonionic surfactant: Effect

    Indian Academy of Sciences (India)

    Micellar solution of nonionic surfactant -dodecyloligo ethyleneoxide surfactant, decaoxyethylene monododecyl ether [CH3(CH2)11(OCH2CH2)10OH], C12E10 in D2O solution have been analysed by small-angle neutron scattering (SANS) at different temperatures (30, 45 and 60°C) both in the presence and absence of ...

  13. Small angle neutron scattering studies on the interaction of cationic

    Indian Academy of Sciences (India)

    The structure of the protein–surfactant complex of bovine serum albumin (BSA) and cationic surfactants has been studied by small angle neutron scattering. At low concentrations, the CTAB monomers are observed to bind to the protein leading to an increase in its size. On the other hand at high concentrations, surfactant ...

  14. Small-angle neutron scattering in materials science - an introduction

    Energy Technology Data Exchange (ETDEWEB)

    Fratzl, P. [Vienna Univ., Inst. fuer Materialphysik, Vienna (Austria)

    1996-12-31

    The basic principles of the application of small-angle neutron scattering to materials research are summarized. The text focusses on the classical methods of data evaluation for isotropic and for anisotropic materials. Some examples of applications to the study of alloys, porous materials, composites and other complex materials are given. (author) 9 figs., 38 refs.

  15. Ultra Small-Angle Neutron Scattering Study of Porous Glass

    International Nuclear Information System (INIS)

    Desai, Reshma R.; Desa, J. A. Erwin; Sen, D.; Mazumder, S.

    2011-01-01

    Compacts of silica micro-spheres prepared for different times at sintering temperatures of 640 deg. C and 740 deg. C have been studied by Ultra Small-Angle Neutron Scattering (USANS) and Scanning Electron Microscopy (SEM). Stress versus strain measurements display several breakage points related to a range of nearest neighbour coordination around each microsphere.

  16. Spin-Echo Small-Angle Neutron Scattering Development

    NARCIS (Netherlands)

    Uca, O.

    2003-01-01

    Spin-Echo Small-Angle Neutron Scattering (SESANS) instrument is a novel SANS technique which enables one to characterize distances from a few nanometers up to the micron range. The most striking difference between normal SANS and SESANS is that in SESANS one gets information in real space, whereas

  17. Small-angle neutron scattering study of structural evolution of ...

    Indian Academy of Sciences (India)

    Small-angle neutron scattering; biological macromolecules; protein solution. PACS Nos 61.12.Ex; 87.14.Ee; 87.15.Nn. Biological macromolecules such as proteins possess a specific shape and charge, which regulate and ... Figure 1a shows the phase diagram of crystallization of 1 wt% lysozyme protein solution as a ...

  18. Ultra-small-angle neutron scattering. History, developments and applications

    International Nuclear Information System (INIS)

    Koizumi, Satoshi; Yamaguchi, Daisuke

    2011-01-01

    Ultra-small-angle neutron scattering (USANS), which is a scattering method observing in a q-region of q=10 -3 nm -1 , was initiated by double crystal (Bonse-Hart) method. Recently, a focusing USANS method was developed by combining a pin-hole type spectrometer and focusing lenses. These two methods, which are complementary to each other, were employed to achieve wide q-observations on microbial cellulose, actin cytoskeleton, tire, and membrane-electrolyte assembly of fuel cell. (author)

  19. Introduction to nanostructural analyses by small-angle neutron scattering

    International Nuclear Information System (INIS)

    Shibayama, Mitsuhiro

    2010-01-01

    It has already passed more than 30 years since small-angle neutron scattering (SANS) technique was applied in structural analyses. SANS is now one of common tools in structure investigations and SANS instruments can be found in any neutron scattering facilities. In particular, SANS plays an important role in the field of soft matter, such as polymer, micelles, gels, vesicles, as well as biological systems and metallurgy. Here, I give a brief survey on (1) the utility of SANS in structural studies, (2) experimental aspects of SANS, and (3) some results obtained so far. (author)

  20. Slow neutron scattering with small angle. 5-6

    International Nuclear Information System (INIS)

    Komura, Shigehiro

    1976-01-01

    The principle, experimental apparatus, and applications of small angle neutron scattering are briefly reviewed. As for the principle, the mathematical expressions for the nuclear and magnetic scattering cross sections of neutrons are given. The advantages of utilizing cold neutrons are also discussed. As for the experimental apparatus, the one at ILL, Grenoble, is introduced with a bird-eye view, a schematic diagram, and the fundamental parameters of the apparatus. The calculated and measured spectra of neutron flux at the exit of a guide tube are also presented. The first example of the small angle neutron scattering is the measurement of void distribution within aluminum single-crystals irradiated with fast neutrons, which was carried out at Juelich. The second problem is the magnetic unevenness in the single crystal of Fe-Ni invar alloy. The third application is the observation of the helical structure of the tobacco mosaic virus in D 2 O. It is suggested that significant informations are expected to be obtained about the conformation of RNA in virus from the results of this observation. (Aoki, K.)

  1. Ultra-small angle neutron scattering on structured materials

    International Nuclear Information System (INIS)

    Hainbuchner, M.

    2000-12-01

    In this work investigations of the inner macroscopic structure of various materials using the ultra small angle neutron scattering (USANS) technique are presented. First, the silicon double crystal and pinhole instruments used for the experiments are described. Then the basics of small angle neutron scattering theory are discussed. The treatment of the experimental scattering measurement data and the fitting of theoretical scattering models are thoroughly discussed, in particular the specific effects of the double crystal instrument geometry are considered. The used numerical procedures of the automatic data treatment and model fitting are presented. The quality and the reliability of these procedures and of the ultra small angle scattering experiments, performed on the neutron optical bench instrument S18 at the high flux reactor of the Institute Laue-Langevin, are illustrated by various measurements. The ultra small angle scattering measurements connect seamlessly or overlap with conventional pinhole measurements. For the determination the inner structure of the investigated materials a combination of ultra small and small angle scattering patterns can be used, which cover more than three orders of magnitude in momentum transfer and ten orders of magnitude in macroscopic differential scattering cross section. The specimens were carefully selected in order to represent a wide range of different materials. Artificial periodic silicon gratings were examined in order to prove high order interference effects. Measuring this kind of samples the performance of an USANS instrument can simply be determined. This allows the comparison of different instruments. For the calibration of the instrument and testing of the data treatment routines suspensions of latex spheres of various diameters were examined. In order to demonstrate that the evaluation of samples showing strong multiple scattering can produce meaningful results, measurements on sintered alumina using various

  2. Small-angle neutron scattering in materials science

    International Nuclear Information System (INIS)

    Fratzl, P.

    1999-01-01

    Small-angle scattering (SAS) in an ideal tool for studying the structure of materials in the mesoscopic size range between 1 and about 100 nanometers. The basic principles of the method are reviewed, with particular emphasis on data evaluation and interpretation for isotropic as well as oriented or single-crystalline materials. Examples include metal alloys, composites and porous materials. The last section gives a comparison between the use of neutrons and (synchrotron) x-rays for small-angle scattering in materials physics. (author)

  3. A more informative approach for characterization of polymer monolithic phases: small angle neutron scattering/ultrasmall angle neutron scattering.

    Science.gov (United States)

    Ford, Kathleen M; Konzman, Brian G; Rubinson, Judith F

    2011-12-15

    Neutron scattering techniques have been used frequently to characterize geological specimens and to determine the structures of glasses and of polymers as solutions, suspensions, or melts. Little work has been reported on their application in determining polymers' structural properties relevant to separations. Here, we present a comparison of characterization results from nitrogen porosimetry and from combined small angle neutron scattering (SANS) and ultrasmall angle neutron scattering (USANS) experiments. We show that SANS is extremely sensitive to the pore characteristics. Both approaches can provide information about porosity and pore characteristics, but the neutron scattering techniques provide additional information in the form of the surface characteristics of the pores and their length scales. Fits of the scattering data show that cylindrical pores are present with diameters down to 0.6 μm and that, for length scales down to approxmately 20 Å, the material shows self-similar (fractal) slopes of -3.4 to -3.6. Comparison of these characteristics with other examples from the scattering literature indicate that further investigation of their meaning for chromatographic media is required.

  4. Small angle neutron scattering from high impact polystyrene

    International Nuclear Information System (INIS)

    Pringle, O.A.

    1981-01-01

    High impact polystyrene (HIPS) is a toughened plastic composed of a polystyrene matrix containing a few percent rubber in the form of dispersed 0.1 to 10 micron diameter rubber particles. Some commercial formulations of HIPS include the addition of a few percent mineral oil, which improves the toughness of the plastic. Little is known about the mechanism by which the mineral oil helps toughen the plastic. It is hypothesized that the oil is distributed only in the rubber particles, but whether this hypothesis is correct was not known prior to this work. The size of the rubber particles in HIPS and their neutron scattering length density contrast with the polystyrene matrix cause HIPS samples to scatter neutrons at small angles. The variation of this small angle neutron scattering (SANS) signal with mineral oil content has been used to determine the location of the oil in HIPS. The SANS spectrometer at the University of Missouri Research Reactor Facility (MURR) was used to study plastic samples similar in composition to commercial HIPS. The MURR SANS spectrometer is used to study the small angle scattering of a vertical beam of 4.75 A neutrons from solid and liquid samples. The scattered neutrons are detected in a 54 x 60 cm 2 position sensitive detector designed and built at MURR. A series of plastic samples of varying rubber and oil content and different rubber domain sizes and shapes were examined on the MURR SANS spectrometer. Analysis of the scattering patterns showed that the mineral oil is about eight to ten times more likely to be found in the rubber particles than in the polystyrene matrix. This result confirmed the hypothesis that the mineral oil is distributed primarily in the rubber particles

  5. Ultra-small-angle scattering with polarized neutrons

    International Nuclear Information System (INIS)

    Jericha, E.; Badurek, G.; Trinker, M.

    2007-01-01

    Ultra-small-angle neutron scattering (USANS) has been established as an effective technique for the study of structures in the micrometre range in recent years. Consequentially this method has been extended to magnetic structures of corresponding size. We present the instrument arrangement and first experimental results. The instrument itself is a double crystal diffractometer in Bonse-Hart configuration which takes advantage of the narrow angular width of the perfect crystal reflection to obtain an extremely high angular resolution of the scattering vector. The neutrons are loss-free polarized by permanent magnetic prisms located between the monochromator crystal and the sample. Neutrons with opposite polarization are separated to a large extent and their different scattering behaviour may be studied in a single measurement without additional manipulation of the neutron spin. In this manner we are able to separate the magnetic and nuclear contribution to the scattering. We present first exemplifying measurements on ferromagnetic rods and wires, and on soft-magnetic ribbons. Related experiments were performed at the USANS facility of the TRIGA reactor at the Vienna University of Technology and at the combined neutron interferometer/USANS instrument S18 at the ILL, Grenoble

  6. Ultra-small-angle scattering with polarized neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Jericha, E. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Vienna (Austria)]. E-mail: jericha@ati.ac.at; Badurek, G. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Vienna (Austria); Trinker, M. [Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Vienna (Austria)

    2007-07-15

    Ultra-small-angle neutron scattering (USANS) has been established as an effective technique for the study of structures in the micrometre range in recent years. Consequentially this method has been extended to magnetic structures of corresponding size. We present the instrument arrangement and first experimental results. The instrument itself is a double crystal diffractometer in Bonse-Hart configuration which takes advantage of the narrow angular width of the perfect crystal reflection to obtain an extremely high angular resolution of the scattering vector. The neutrons are loss-free polarized by permanent magnetic prisms located between the monochromator crystal and the sample. Neutrons with opposite polarization are separated to a large extent and their different scattering behaviour may be studied in a single measurement without additional manipulation of the neutron spin. In this manner we are able to separate the magnetic and nuclear contribution to the scattering. We present first exemplifying measurements on ferromagnetic rods and wires, and on soft-magnetic ribbons. Related experiments were performed at the USANS facility of the TRIGA reactor at the Vienna University of Technology and at the combined neutron interferometer/USANS instrument S18 at the ILL, Grenoble.

  7. SANS [small-angle neutron scattering] from polymers and colloids

    International Nuclear Information System (INIS)

    Hayter, J.B.

    1987-01-01

    Small-angle neutron scattering (SANS) has been remarkably successful in providing detailed quantitative structural information on complex everyday materials, such as polymers and colloids, which are often of considerable industrial as well as academic interest. This paper reviews some recent SANS experiments on polymers and colloids, including ferrofluids, and discusses the use of these apparently complex systems as general physical models of the liquid or solid state

  8. Small angle neutron scattering experiment and raw data reduction

    International Nuclear Information System (INIS)

    Wei Guohai; Li Tianfu; Zhang Li; Wang Yu; Wang Hongli; Liu Xiangfeng

    2010-01-01

    Small angle neutron scattering (SANS) technique is a powerful tool for nanometer structural analysis of materials. The process of SANS measurement, and the raw data reduction, is relatively complicated. In order to obtain the absolute SANS intensity, one needs to measure intensities of the incident and scattered beams, the sample transmission, the background, the scattering and transmission of the empty cell etc. If a wide scattering vector range is needed, one has to measure the same sample under different instrument configurations. Also, a large number of data treatments are needed before one obtains the SANS data for further analysis. In this paper, after a short introduction to the SANS basic theory and the experimental system, we focus on the raw data reduction method, in which the averaging and the combination of the isotropically scattered data are discussed in detail. (authors)

  9. Small-angle neutron scattering instrument at MINT

    International Nuclear Information System (INIS)

    Mohd Ali Sufi; Yusof Abdullah; Razali Kassim; Hamid; Shahidan Radiman; Mohammad Deraman; Abdul Ghaffar Ramli

    1996-01-01

    The Small Angle Neutron Scattering (SANS) Instrument has been developed at Malaysian Institute for Nuclear Technology Research (MINT) for studying structural properties of materials on the length scale 1 nm to 100 nm. This is the length scale which is relevant for many topics within soft condensed matter, like polymers, colloids, biological macromolecules, etc. The SANS is a complementary technique to X-ray and electron scattering. However, while these later techniques give information on structures near surface, SANS concerns the structure of the bulk. Samples studied by SANS technique are typically bulk materials of the sizes mm's to cm's, or materials dissolved in a liquid. This paper described the general characteristics of SANS instrument as well as the experimental formulation in neutron scattering. The preliminary results obtained by this instrument are shown

  10. Quokka: The Small-Angle Neutron Scattering Instrument at OPAL

    International Nuclear Information System (INIS)

    Gilbert, Elliot; Noakes, Terry; Schulz, Jamie; Baxter, Peter; Darmann, Frank; Hauser, Nick; Abbeywick, Peter; Brule, Alain; Imamovic, Eno; Christoforidis, Jason

    2005-01-01

    Full text: A small-angle neutron scattering (SANS) instrument is being designed as part of the initial instrument suite for the 20-MW OPAL Reactor. The new instrument, receiving neutrons from a large liquid-D2 cold source, will be in the spirit of the worlds best facilities and will greatly build upon the Australian Nuclear Science and Technology Organisations existing expertise and facilities. Scheduled for completion in July 2006, it will provide Australian and international researchers with opportunities to access state-of-the-art SANS instrumentation. The details of the new SANS will be presented. (author)

  11. Small-angle neutron scattering analyses of nanoemulsion

    International Nuclear Information System (INIS)

    Kume, Takuji

    2010-01-01

    A stable nanoemulsion consisting of nanometer-sized oil droplets in water having a self-standing capability was prepared by high-pressure emulsification. Rheological measurements show that the nanoemulsion has a yield stress. Small-angle neutron scattering (SANS) revealed the presence of an ordered crystal-like lattice structure in addition to spherical domains with a radius of 17 nm. A mixed solution of 2-hydroxyethyl cellulose and dilution of the nanoemulsion has shear-thickening behavior (shear-induced gelation). Real-time SANS measurements with a Couette geometry as a function of shear rate showed an increase in the scattering intensity exclusively at low scattering angle region. However, neither aggregation nor deformation of droplet was detected and the SANS patterns remained isotropic irrespective of shear rate. A possible mechanism of gelation is proposed from the viewpoint of shear-induced percolation transition. (author)

  12. Small-angle neutron scattering and inelastic neutron scattering studies on β-cyclodextrins and hydroxypropyl-β-cyclodextrins

    International Nuclear Information System (INIS)

    Maccarrone, S.; Magazu, S.; Migliardo, F.; Mondio, F. Mondio

    2004-01-01

    This work reports new experimental neutron scattering results on β-cyclodextrins and hydroxypropyl-β-cyclodextrins. The small angle neutron scattering analysis shows that the typical conformation of the investigated systems in crystalline state is also maintained in aqueous solution. Inelastic neutron scattering results emphasize the more 'crystalline' character of β-cyclodextrins in comparison with hydroxypropyl β-cyclodextrins from the differences in the vibrational spectra of these compounds

  13. Small-angle neutron scattering measurement of silicon nanoparticle size

    International Nuclear Information System (INIS)

    Choi, Jonghoon; Tung, Shih-Huang; Wang, Nam Sun; Reipa, Vytas

    2008-01-01

    We have determined the particle size distribution profiles of octane-terminated silicon nanoparticle suspensions, produced using the sonication of electrochemically etched Si wafers. Small-angle neutron scattering data was analyzed separately in high (0.4 nm -1 -1 ) and low (q -1 ) scattering vector ranges. Data in the high q range is consistent with the log-normal distribution of isolated spherical particles with median diameter d = 3 ± 0.2 nm. Particle sizes were also indirectly assessed from photoluminescence and optical transmission spectroscopy using the size/bandgap relation: E g = 3.44d -0.5 , where E g is in eV and d in nm. Both measurements were consistent with the particle size distribution profiles, estimated from ANS data fitting and TEM image analysis. A subpopulation of larger, irregular shape structures in the size range 10-50 nm was also indicated by neutron scattering in the low q range and HRTEM images. However, further studies are warranted to explain a relationship between the slope of scattering intensity versus scattering vector dependence in the intermediate scattering vector range (0.4 nm -1 -1 ) and the role of non-geometrical Si nanoparticle characteristics (mutual interaction forces, surface termination, etc)

  14. The single-angle neutron scattering facility at Pelindaba

    International Nuclear Information System (INIS)

    Hofmeyr, C.; Mayer, R.M.; Tillwick, D.L.; Starkey, J.R.

    1978-05-01

    The small-angle neutron scattering facility at the SAFARI-1 reactor is described in detail, and with reference to theoretical and practical design considerations. Inexpensive copper microwave guides used as a guide-pipe for slow neutrons provided the basis for a useful though comparatively simple facility. The neutron-spectrum characteristics of the final facility in different configurations of the guide-pipe (both S and single-curved) agree wel with expected values based on results obtained with a test facility. The design, construction, installation and alignment of various components of the facility are outlined, as well as intensity optimisation. A general description is given of experimental procedures and data-aquisition electronics for the four-position sample holder and counter array of up to 18 3 He detectors and a beam monitor [af

  15. Resolution of pulsed-source small-angle neutron scattering

    International Nuclear Information System (INIS)

    Seeger, P.A.; Pynn, R.

    1986-01-01

    An analytic form is found for resolution of small-angle scattering in a plane, at a pulsed source with a white neutron spectrum. The function is found to be asymmetric at low values of Q and to have broad tails if data recorded over the entire wavelength range are combined. Monte Carlo calculations in three dimensions and including realistic spectra and collimator geometry confirm these features and provide ''data'' for studying the question of what regions of scattering angle and wavelength should be retained in data reduction. Comparisons are made with a spectrometer at a reactor, based on the accuracy, statistical precision, and time required to collect data for (simulated) monodisperse hard spheres of various radii. (orig.)

  16. Multiple magnetic scattering in small-angle neutron scattering of Nd–Fe–B nanocrystalline magnet

    Science.gov (United States)

    Ueno, Tetsuro; Saito, Kotaro; Yano, Masao; Ito, Masaaki; Shoji, Tetsuya; Sakuma, Noritsugu; Kato, Akira; Manabe, Akira; Hashimoto, Ai; Gilbert, Elliot P.; Keiderling, Uwe; Ono, Kanta

    2016-01-01

    We have investigated the influence of multiple scattering on the magnetic small-angle neutron scattering (SANS) from a Nd–Fe–B nanocrystalline magnet. We performed sample-thickness- and neutron-wavelength-dependent SANS measurements, and observed the scattering vector dependence of the multiple magnetic scattering. It is revealed that significant multiple scattering exists in the magnetic scattering rather than the nuclear scattering of Nd–Fe–B nanocrystalline magnet. It is considered that the mean free path of the neutrons for magnetic scattering is rather short in Nd–Fe–B magnets. We analysed the SANS data by the phenomenological magnetic correlation model considering the magnetic microstructures and obtained the microstructural parameters. PMID:27321149

  17. Multiple magnetic scattering in small-angle neutron scattering of Nd-Fe-B nanocrystalline magnet.

    Science.gov (United States)

    Ueno, Tetsuro; Saito, Kotaro; Yano, Masao; Ito, Masaaki; Shoji, Tetsuya; Sakuma, Noritsugu; Kato, Akira; Manabe, Akira; Hashimoto, Ai; Gilbert, Elliot P; Keiderling, Uwe; Ono, Kanta

    2016-06-20

    We have investigated the influence of multiple scattering on the magnetic small-angle neutron scattering (SANS) from a Nd-Fe-B nanocrystalline magnet. We performed sample-thickness- and neutron-wavelength-dependent SANS measurements, and observed the scattering vector dependence of the multiple magnetic scattering. It is revealed that significant multiple scattering exists in the magnetic scattering rather than the nuclear scattering of Nd-Fe-B nanocrystalline magnet. It is considered that the mean free path of the neutrons for magnetic scattering is rather short in Nd-Fe-B magnets. We analysed the SANS data by the phenomenological magnetic correlation model considering the magnetic microstructures and obtained the microstructural parameters.

  18. A novel small-angle neutron scattering detector geometry.

    Science.gov (United States)

    Kanaki, Kalliopi; Jackson, Andrew; Hall-Wilton, Richard; Piscitelli, Francesco; Kirstein, Oliver; Andersen, Ken H

    2013-08-01

    A novel 2π detector geometry for small-angle neutron scattering (SANS) applications is presented and its theoretical performance evaluated. Such a novel geometry is ideally suited for a SANS instrument at the European Spallation Source (ESS). Motivated by the low availability and high price of 3 He, the new concept utilizes gaseous detectors with 10 B as the neutron converter. The shape of the detector is inspired by an optimization process based on the properties of the conversion material. Advantages over the detector geometry traditionally used on SANS instruments are discussed. The angular and time resolutions of the proposed detector concept are shown to satisfy the requirements of the particular SANS instrument.

  19. TOF-SEMSANS—Time-of-flight spin-echo modulated small-angle neutron scattering

    NARCIS (Netherlands)

    Strobl, M.; Tremsin, A.S.; Hilger, A.; Wieder, F.; Kardjilov, N.; Manke, I.; Bouwman, W.G.; Plomp, J.

    2012-01-01

    We report on measurements of spatial beam modulation of a polarized neutron beam induced by triangular precession regions in time-of-flight mode and the application of this novel technique spin-echo modulated small-angle neutron scattering (SEMSANS) to small-angle neutron scattering in the very

  20. Spin echo small angle neutron scattering using a continuously pumped (3)He neutron polarisation analyser.

    Science.gov (United States)

    Parnell, S R; Washington, A L; Li, K; Yan, H; Stonaha, P; Li, F; Wang, T; Walsh, A; Chen, W C; Parnell, A J; Fairclough, J P A; Baxter, D V; Snow, W M; Pynn, R

    2015-02-01

    We present a new instrument for spin echo small angle neutron scattering (SESANS) developed at the Low Energy Neutron Source at Indiana University. A description of the various instrument components is given along with the performance of these components. At the heart of the instrument are a series of resistive coils to encode the neutron trajectory into the neutron polarisation. These are shown to work well over a broad range of neutron wavelengths. Neutron polarisation analysis is accomplished using a continuously operating neutron spin filter polarised by Rb spin-exchange optical pumping of (3)He. We describe the performance of the analyser along with a study of the (3)He polarisation stability and its implications for SESANS measurements. Scattering from silica Stöber particles is investigated and agrees with samples run on similar instruments.

  1. Ultra-small-angle neutron scattering with azimuthal asymmetry.

    Science.gov (United States)

    Gu, X; Mildner, D F R

    2016-06-01

    Small-angle neutron scattering (SANS) measurements from thin sections of rock samples such as shales demand as great a scattering vector range as possible because the pores cover a wide range of sizes. The limitation of the scattering vector range for pinhole SANS requires slit-smeared ultra-SANS (USANS) measurements that need to be converted to pinhole geometry. The desmearing algorithm is only successful for azimuthally symmetric data. Scattering from samples cut parallel to the plane of bedding is symmetric, exhibiting circular contours on a two-dimensional detector. Samples cut perpendicular to the bedding show elliptically dependent contours with the long axis corresponding to the normal to the bedding plane. A method is given for converting such asymmetric data collected on a double-crystal diffractometer for concatenation with the usual pinhole-geometry SANS data. The aspect ratio from the SANS data is used to modify the slit-smeared USANS data to produce quasi-symmetric contours. Rotation of the sample about the incident beam may result in symmetric data but cannot extract the same information as obtained from pinhole geometry.

  2. Small-angle scattering of neutrons from normal and superfluid liquid helium

    International Nuclear Information System (INIS)

    Tsipenyuk, Yu.M.; Kirichek, O.; Petrenko, O.

    2013-01-01

    The results of experiments on small-angle neutron scattering in liquid helium in the range of temperatures of 1-5 K, performed on a neutron pulse source ISIS (England), are presented. The detailed measurements of angular distribution of scattered neutrons allowed one to observe an essential change in temperature dependence of the second moment of pair correlation function (the first derivative of angular distribution at small angles of scattering). At high temperatures the angular distribution of scattered neutrons follows the classical description of small-angle scattering, but at temperatures below the l-point a quantum behavior is observed neutron-scattering by quantum fluctuations. It is experimentally confirmed that in the whole temperature range the cross-section of neutron scattering at a zero angle is determined by the classical thermodynamic fluctuations of density.

  3. Small-angle neutron scattering at pulsed spallation sources

    International Nuclear Information System (INIS)

    Seeger, P.A.; Hjelm, R.P. Jr.

    1990-01-01

    The importance of small-angle neutron scattering (SANS) in biological, chemical, physical, and engineering research mandates that all intense neutron sources be equipped with SANS instruments. Four existing instruments are described, and the general differences between pulsed-source and reactor-based instrument designs are discussed. The basic geometries are identical, but dynamic range is achieved by using a broad band of wavelengths (with time-of-flight analysis) rather than by moving the detector. This allows a more optimized collimation system. Data acquisition requirements at a pulsed source are more severe, requiring large, fast histogramming memories. Data reduction is also more complex, as all wave length-dependent and angle-dependent backgrounds and non-linearities must be accounted for before data can be transformed to intensity vs Q. A comparison is shown between the Los Alamos pulsed instrument and D-11 (Institute Laue-Langevin), and examples from the four major topics of the conference are shown. The general conclusion is that reactor-based instruments remain superior at very low Q or if only a narrow range of Q is required, but that the current generation of pulsed-source instruments is competitive at moderate Q and may be faster when a wide range of Q is required. In principle, a user should choose which facility to use on the basis of optimizing the experiment; in practice the tradeoffs are not severe and the choice is usually made on the basis of availability

  4. Data reduction for time-of-flight small-angle neutron scattering with virtual neutrons

    Science.gov (United States)

    Du, Rong; Tian, Haolai; Zuo, Taisen; Tang, Ming; Yan, Lili; Zhang, Junrong

    2017-09-01

    Small-angle neutron scattering (SANS) is an experimental technique to detect material structures in the nanometer to micrometer range. The solution of the structural model constructed from SANS strongly depends on the accuracy of the reduced data. The time-of-flight (TOF) SANS data are dependent on the wavelength of the pulsed neutron source. Therefore, data reduction must be handled very carefully to transform measured neutron events into neutron scattering intensity. In this study, reduction algorithms for TOF SANS data are developed and optimized using simulated data from a virtual neutron experiment. Each possible effect on the measured data is studied systematically, and suitable corrections are performed to obtain high-quality data. This work will facilitate scientific research and the instrument design at China Spallation Neutron Source.

  5. Project study of a small-angle neutron scattering apparatus

    International Nuclear Information System (INIS)

    Schedler, E.; Pollet, J.L.

    1979-03-01

    This design study deals with the set up of a low angle scattering apparatus in the HMI reactor hall in Berlin. The experiences of other institutes with facilities of a similar type, - especially with D11 and D17 of the ILL in Grenoble, the set up the KFA in Juelich and of the PTB in Braunschweig -, are included to a large extend. The aim of this paper is - to define the necessary boundary conditions for the construction (including: installation of a cold source, the beam line, the neutron guide pipe and an extention of the reactor hall), -to determine the properties of the planned apparatus, especially in comparison with D11, probably the most versatile instrument, - to make desitions for the design of the components, - to work out the detailed drawings for construction - to estimate the costs and the time necessary for construction, if industrial manufacturers set up the project. (orig.) [de

  6. Radiation damage study using small-angle neutron scattering

    Science.gov (United States)

    Rétfalvi, E.; Török, Gy; Rosta, L.

    2000-03-01

    Nuclear radiation provides important changes in the microstructure of metallic components of nuclear power plant and research reactors, influencing their mechanical properties. The investigation of this problem has primary interest for the safety and life-time of such nuclear installations. For the characterization of this kind of nanostructures small angle neutron scattering technique is a very useful tool. We have carried out experiments on samples of irradiated reactor vessel material and welded components of VVER-440-type reactors on the SANS instrument at the Budapest Research Reactor. In our measurements irradiated as well as non-irradiated samples were compared and magnetic field was applied for viewing the magnetic structure effects of the materials. A clear modification of the structure due to irradiation was obtained. Our data were analyzed by the ITP92 code, the inverse Fourier transform program of O. Glatter [1].

  7. User's guide for the small-angle neutron scattering facility

    International Nuclear Information System (INIS)

    Vlak, W.A.H.M.; Werkhoven, E.J.

    1989-04-01

    This report serves as a manual for the users of the small-angle neutron scattering instrument located at beamport HB3 of the High Flux Reactor in Petten. The main part of the text is devoted to the control of the facility and the data handling by means of a μVAX computer. Also, the various possibilities to access the facility across computer networks are discussed. A collection of menu-driven and command-driven programs, which utilize the flexibility of the VMS operating system without requiring detailed knowledge of the user about the computer environment, enables to control the instrument. For the convenience of the experienced user, who might wish to update or extend the software, a technical supplement is included. 15 figs.; 8 refs

  8. Field study of nanoparticles by small angle neutron scattering

    International Nuclear Information System (INIS)

    Mirebeau, I.; Hennion, M.; Bellouard, C.

    1994-01-01

    In nanometric iron particles, magnetic correlations are determined by small angle neutron scattering and compared to their values calculated in a simple superparamagnetic model. The introduction of a Lorentzian shape for the magnetic form factor is necessary to obtain a good fit of the data. This reveals two extra features: a spin disorder at the surface of the particles which persists in applied field, and a distribution in the particle sizes not probed by X-rays. The field alignment becomes easier with decreasing temperature. This is no longer true for samples with bigger and closer-packed particles, where strong dipolar interactions develop at low temperatures and oppose to the external field. 4 figs., 3 refs

  9. The small angle neutron scattering study on the segmented polyurethane

    Energy Technology Data Exchange (ETDEWEB)

    Sudirman; Gunawan; Prasetyo, S.M.; Karo Karo, A.; Lahagu, I.M.; Darwinto, Tri [Materials Science Research Center, National Nuclear Energy Agency, Serpong, Tangerang (Indonesia)

    1999-10-01

    The distance between hard segment (HS) and soft segment (SS) of segmented polyurethane have been determined using the Small Angle Neutron Scattering (SANS) technique. The segmented Polyurethanes (SPU) are linear multiblock copolymers, which include elastomer thermoplastic. SPU consist of hard segment and soft segment, each has tendency to make a group with similar type to form a domain. The soft segments used were polypropylene glycol (PPG) and 4,4 diphenylmethane diisocyanate (MDI), while l,4 butanediol (BD) was used as hard segment. The characteristic of SPU depends on its phase structure which is affected by several factors, such as type of chemical formula and the composition of the HS and SS, solvent as well as the synthesizing process. The samples used in this study were SPU56 and SPU68. Based on the appearance of SANS profile, it was obtained that domain distances are 12.32 nm for the SPU56 and 19 nm for the SPU68. (author)

  10. A small angle neutron scattering study of thermoplastic elastomer

    Energy Technology Data Exchange (ETDEWEB)

    Sutiarso; Edy Giri, R. Putra; Andon, Insani; Sudirman; Sudaryanto [Materials Science Research Centre, National Atomic Energy Agency, Jakarta (Indonesia)

    1998-10-01

    A bilateral scientific cooperation, in the small angle neutron scattering has been agreed upon between CIAE, China and BATAN, Indonesia as well as MINT Malaysia. As stated in the agreed proposal that the objective of this cooperation, in the initial stage (stage-1), was to have a regional intercomparison measurements of SANS instruments in order to determine their characteristic/performance. Therefore, this report is supposed to describe the progress in the SANS instrument development of each country involved during the period of 1996/97 and some activities related to the SANS instrument. Since, up to now, we have not yet received any progresses reported from either China or Malaysia, this report will describe the progress of SANS`s activities in BATAN only. (author)

  11. Small angle neutron scattering study of Linde 80 RPV welds

    International Nuclear Information System (INIS)

    Wirth, B.D.; Odette, G.R.; Lucas, G.E.; Spooner, S.E.

    1999-01-01

    Small angle neutron scattering (SANS) results are presented for Linde 80 welds irradiated, as part of the B and W Owners Group Integrated Surveillance Program, at low fluxes ( 15 n/m 2 -s) to fluences from 0.29 to 3.5 x 10 23 n/m 2 (E > 1 MeV) at irradiation temperatures from 276 to 292 C. The welds all contain about 0.6 Ni (all composition units are in wt.%), 0.009 to 0.18 P and 0.05 to 0.28 Cu. In the welds with significant amounts of copper (>0.2 Cu) the measured defect scattering cross sections were consistent with either: (a) copper rich precipitates (CRPs) alloyed with manganese and nickel; or (b) dominant CRP scattering, plus a weak contribution from so-called matrix defect features. Similar weak scattering was observed in a low copper (0.06 Cu) weld. The identity of matrix defect features cannot be determined from the SANS data alone, but the scattering is consistent with the presence of subnanometer vacancy cluster-solute complexes. The general character of the CRPs, and the trends in their number density, volume fraction and average radius as a function of fluence and irradiation temperature, are very similar to those observed in a wide range of pressure vessel-type steels irradiated in test reactors at intermediate to high flux. The SANS data in the surveillance welds is also in unity with: (a) thermodynamic-kinetic radiation enhanced diffusion models of CRP evolution; (b) mechanical property changes, including predictions of the correlations of the surveillance data base; and (c) an atomic scale, atom probe field ion microscopy study into the nanostructure-chemistry of a CRP

  12. New development in nanostructure analysis by smaller-angle neutron scattering instrument of J-PARC

    International Nuclear Information System (INIS)

    Suzuki, Jun-ichi; Shinohara, Takenao; Takata, Shin-ichi; Oku, Takayuki; Suzuya, Kentaro; Aizawa, Kazuya; Arai, Masatoshi; Otomo, Toshiya; Sugiyama, Masaaki

    2008-01-01

    The technique of small-angle neutron scattering has been used to study structures of size between about 1 nm and 10 μm in materials and life sciences. This article introduces the smaller-angle neutron scattering instrument projected in J-PARC, which will produce new development in nanostructure analysis. (author)

  13. Wavelength-independent constant period spin-echo modulated small angle neutron scattering

    NARCIS (Netherlands)

    Sales, Morten; Plomp, J.; Habicht, Klaus; Tremsin, Anton; Bouwman, W.G.; Strobl, Markus

    2016-01-01

    Spin-Echo Modulated Small Angle Neutron Scattering (SEMSANS) in Time-of-Flight (ToF) mode has been shown to be a promising technique for measuring (very) small angle neutron scattering (SANS) signals and performing quantitative Dark-Field Imaging (DFI), i.e., SANS with 2D spatial resolution.

  14. New Very Small Angle Neutron Scattering (VSANS) Instrument

    International Nuclear Information System (INIS)

    Van Every, E; Kulesza, J; Deyhim, A

    2016-01-01

    The design of a new Very Small Angle Neutron Scattering (VSANS) Instrument for use in National Institute of Standards And Technology (NIST) will be discussed. This instrument is similar to a shorter instrument we designed and delivered to ANSTO in Australia called the Bilby SANS instrument. The NIST VSANS and the ANSTO Bilby SANS instruments have very similar dimensions for length and diameter and have similar requirements for internal detector motion, top access port, walkway supports, and ports; however, the Bilby SANS instrument vacuum requirement was lower (7.5×10-5 Torr) and the entire (60,000 pound) vessel was required to move 1.5 meters on external rails with a repeatability of 100 um, which ADC achieved. The NIST VSANS length is 24 meter, internal diameter 2.3 meter with three internal carriages. The NIST VSANS instrument, which covers the usual SANS range will also allow configuration to cover the range between q ∼| 10 -4 A -1 to 10 -3 A -1 with a sample beam current of (10 4 neutrons/s). The key requirements are a second position-sensitive detector system having a 1 mm pixel size and a longer sample-detector flight path of 20 m (i.e., a 40 m instrument). (paper)

  15. Small-angle neutron scattering study of natural aquatic nanocolloids.

    Science.gov (United States)

    Jarvie, Helen P; King, Stephen M

    2007-04-15

    We examine the potential of small-angle neutron scattering (SANS) as a quantitative tool for studying nanostructure and length scales in natural freshwater aquatic colloidal dispersions (river water, river bed sediments, agricultural field drainage and slurry). Our results show that natural aquatic colloids are generally fractal with 3D network-type structures. None of these structures are consistent with diffusion-limited (DLCA) or reaction-limited (RLCA) particleparticle aggregation processes. The results also suggest three characteristic length scales: one ca. 3-10 nm, which we identify with "primary particle" sizes, another of ca. 20-50 nm suggestive of small aggregates, and the last ca. 50-200 nm which we postulate arises from transient networks of the aggregates. The role of organic matter in mediating colloid structure in aquatic dispersions was examined by neutron contrast variation and by measuring samples both before and after treatment with hydrogen peroxide. The results suggest that the aggregate network structure is mediated by organic matter.

  16. The measurement of neutron scattering cross sections at small angles

    International Nuclear Information System (INIS)

    Qi, H.Q.; Liu, Y.C.; Chen, Z.P.; Wu, X.C.; Wang, W.H.; Zhang, J.

    1985-08-01

    A position sensitive neutron detector was used to measure the scattering cross sections of 14.7 MeV neutrons from Pb between 3 0 and 9 0 . The method to correct the effects of finite positional resolution by unfolding positional spectrum was studied. (author)

  17. Ultra small angle neutron scattering from superconducting filament structures

    International Nuclear Information System (INIS)

    Amenitsch, H.

    1999-01-01

    With a perfect crystal camera, ultra small-angle scattering measurements were performed to investigate the internal diffusion process of tin inside a superconducting multi-filament wire caused by a temperature treatment. Commercially available Nb 3 Sn superconducting multi-filament wires were treated at 700 C with varying ageing times up to 144 h. A theoretical model taking into account the geometrical form, the size distribution, the interference term and the multiple scattering has been developed to understand and to describe the small angle diffraction pattern. Additionally, the diffusion of H and D into the filament wires was used to vary the scattering length density inside the wires. The results show a direct relationship between the different technological treatments and the characteristic small-angle scattering parameters, like Guinier radius and small-angle scattering probability. (orig.) [de

  18. Diffraction limit of the theory of multiple small-angle neutron scattering by a dense system of scatterers

    Science.gov (United States)

    Dzheparov, F. S.; Lvov, D. V.

    2016-02-01

    Multiple small-angle neutron scattering by a high-density system of inhomogeneities has been considered. A combined approach to the analysis of multiple small-angle neutron scattering has been proposed on the basis of the synthesis of the Zernike-Prince and Moliére formulas. This approach has been compared to the existing multiple small-angle neutron scattering theory based on the eikonal approximation. This comparison has shown that the results in the diffraction limit coincide, whereas differences exist in the refraction limit because the latter theory includes correlations between successive scattering events. It has been shown analytically that the existence of correlations in the spatial position of scatterers results in an increase in the number of unscattered neutrons. Thus, the narrowing of spectra of multiple small-angle neutron scattering observed experimentally and in numerical simulation has been explained.

  19. Evaluation of multiple small-angle neutron scattering including magnetic interactions

    Czech Academy of Sciences Publication Activity Database

    Šaroun, Jan

    2007-01-01

    Roč. 40, s1 (2007), s701-s705 ISSN 0021-8898. [XIII International Conference on Small - Angle Scattering . Kyoto, 09.07.2006-13.07.2006] Institutional research plan: CEZ:AV0Z10480505 Keywords : multiple small - angle scattering * neutron scattering * ferromagnets Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.629, year: 2007

  20. Application of a double reflection multilayer monochromator to small-angle cold neutron scattering

    International Nuclear Information System (INIS)

    Sugiyama, Masaaki; Kawai, Takeshi; Ebisawa, Toru; Tasaki, Seiji; Maeda, Yutaka.

    1994-01-01

    The flux profile and the spectra of the neutron beam from the cold neutron guide tube, CN-2, which is installed at the cold neutron source of Kyoto University Reactor were measured with Au foil activation and time-of-flight methods. By using the cold neutron beam, the characteristics of a double reflection multilayer monochromator were studied for a small angle neutron scattering spectrometer. The reflectivity of the monochromator and the wavelength resolution were found to be 78% and 15% at the wavelength of 5.5 A respectively. These values indicate that the monochromator gives quite a good performance for small-angle cold neutron scattering experiments. (author)

  1. Steel research using neutron beam techniques. In-situ neutron diffraction, small-angle neutron scattering and residual stress analysis

    International Nuclear Information System (INIS)

    Sueyoshi, Hitoshi; Ishikawa, Nobuyuki; Yamada, Katsumi; Sato, Kaoru; Nakagaito, Tatsuya; Matsuda, Hiroshi; Arakaki, Yu; Tomota, Yo

    2014-01-01

    Recently, the neutron beam techniques have been applied for steel researches and industrial applications. In particular, the neutron diffraction is a powerful non-destructive method that can analyze phase transformation and residual stress inside the steel. The small-angle neutron scattering is also an effective method for the quantitative evaluation of microstructures inside the steel. In this study, in-situ neutron diffraction measurements during tensile test and heat treatment were conducted in order to investigate the deformation and transformation behaviors of TRIP steels. The small-angle neutron scattering measurements of TRIP steels were also conducted. Then, the neutron diffraction analysis was conducted on the high strength steel weld joint in order to investigate the effect of the residual stress distribution on the weld cracking. (author)

  2. Small-angle scattering from neutron-irradiated amorphous Pd80Si20

    International Nuclear Information System (INIS)

    Doi, K.; Kayano, H.; Masumoto, T.

    1978-01-01

    Small-angle scattering intensities were observed for amorphous Pd 80 Si 20 which was irradiated by fast neutrons to a fluence of 5 X 10 20 neutrons cm -2 . A broad hump was observed at 2 sin theta/lambda = 0.05 A -1 . The structure inhomogeneities produced by the neutron irradiation are discussed with the aid of the results of wide-angle scattering measurements. (Auth.)

  3. Small angle neutron scattering studies on the interaction of cationic ...

    Indian Academy of Sciences (India)

    in a wide variety of industrial, biological, pharmaceutical and cosmetic systems. The mechanism of unfolding of proteins on addition of the surfactant has been studied by several techniques such as circular dichroism (CD), nuclear magnetic resonance (NMR), microcalorimetry, light scattering and small angle scattering.

  4. Heparin's solution structure determined by small-angle neutron scattering.

    Science.gov (United States)

    Rubinson, Kenneth A; Chen, Yin; Cress, Brady F; Zhang, Fuming; Linhardt, Robert J

    2016-12-01

    Heparin is a linear, anionic polysaccharide that is widely used as a clinical anticoagulant. Despite its discovery 100 years ago in 1916, the solution structure of heparin remains unknown. The solution shape of heparin has not previously been examined in water under a range of concentrations, and here is done so in D2 O solution using small-angle neutron scattering (SANS). Solutions of 10 kDa heparin-in the millimolar concentration range-were probed with SANS. Our results show that when sodium concentrations are equivalent to the polyelectrolyte's charge or up to a few hundred millimoles higher, the molecular structure of heparin is compact and the shape could be well modeled by a cylinder with a length three to four times its diameter. In the presence of molar concentrations of sodium, the molecule becomes extended to nearly its full length estimated from reported X-ray measurements on stretched fibers. This stretched form is not found in the presence of molar concentrations of potassium ions. In this high-potassium environment, the heparin molecules have the same shape as when its charges were mostly protonated at pD ≈ 0.5, that is, they are compact and approximately half the length of the extended molecules. © 2016 Wiley Periodicals, Inc.

  5. Characterization of Polystyrene Soft Nanoparticles Using Small Angle Neutron Scattering

    Science.gov (United States)

    Martin, Halie; White, Tyler; Saito, Tomonori; Dadmun, Mark

    Polymer nanocomposites have become a prominent area of research recently. With a growing variety of nanoparticles available, research probing the influence of particle morphology on the overall nanocomposite properties is also increasing. Nanoparticle dispersion is controlled by both the chemical nature and morphology of the nanoparticle where a crosslinked, fuzzy organic nanoparticle is anticipated to enhance the overall miscibility and create a homogenous dispersion within a like-polymer matrix. A semi-batch microemulsion polymerization forms organic, soft nanoparticles where the precise structure of the nanoparticle is controlled by monomer rate of addition and crosslinking density. We will report small angle neutron scattering results that correlate synthetic conditions to the structural characteristics of soft nanoparticles. This analysis provides characterization of the individual nanoparticle molecular weight, the radius of the crosslinked core, the thickness of the fuzzy interfacial layer, and provides insight into the overall topography of the soft nanoparticle. This research provides a pathway to investigate the effect of nanoscale structural features of the nanoparticle on their individual properties and those of nanocomposites that contain these soft nanoparticles. DOE-BES, Division of Materials Sciences and Engineering.

  6. The National Facility for Small-Angle Neutron Scattering - five years' operating experience

    International Nuclear Information System (INIS)

    Koehler, W.C.; Bunick, G.J.; Child, H.R.; Hayter, J.B.; Lin, J.S.; Maddox, L.; Spooner, S.; Wignall, G.D.

    1986-01-01

    At the time of this Conference on Neutron Scattering, the ORNL-NSF-DOE National Facility for Small-Angle Neutron Scattering will have been operating routinely in a full-time user mode for nearly five years. The Facility, located at the High Flux Isotope Reactor at ORNL, is part of the National Center for Small-Angle Scattering Research. Operating experience and scientific highlights for the past five years are surveyed. (orig.)

  7. Grazing incident small angle neutron scattering. Analysis of self-assembly of softmatters in thin films

    International Nuclear Information System (INIS)

    Yokoyama, Hideaki

    2009-01-01

    Grazing incident small angle scattering has been used for the analysis of surface and thin film structures. X-ray in particular is widely used for such analysis and called grazing incident small angle X-ray scattering (GISAXS). However, a very limited number of studied has been done using grazing incident small angle neutron scattering (GISANS) primarily due to low intensity of neutron beam. The arising JPARC neutron source will enable us to use GISANS to analyze thin film structures of softmatter. This report provides a basic concept of GISAS using an example of the analysis of nanocellular thin films fabricated by block copolymer template with supercritical carbon dioxide (BSTSC). (author)

  8. Neutron scattering. Lectures

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2012-07-01

    The following topics are dealt with: Neutron scattering in contemporary research, neutron sources, symmetry of crystals, diffraction, nanostructures investigated by small-angle neutron scattering, the structure of macromolecules, spin dependent and magnetic scattering, structural analysis, neutron reflectometry, magnetic nanostructures, inelastic scattering, strongly correlated electrons, dynamics of macromolecules, applications of neutron scattering. (HSI)

  9. Neutron scattering. Lectures

    International Nuclear Information System (INIS)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner

    2012-01-01

    The following topics are dealt with: Neutron scattering in contemporary research, neutron sources, symmetry of crystals, diffraction, nanostructures investigated by small-angle neutron scattering, the structure of macromolecules, spin dependent and magnetic scattering, structural analysis, neutron reflectometry, magnetic nanostructures, inelastic scattering, strongly correlated electrons, dynamics of macromolecules, applications of neutron scattering. (HSI)

  10. Spherical sector model for describing the experimental small-angle neutron scattering data for dendrimers

    International Nuclear Information System (INIS)

    Rogachev, A. V.; Cherny, A. Yu.; Ozerin, A. N.; Gordeliy, V. I.; Kuklin, A. I.

    2007-01-01

    A new model for interpreting the results of small-angle neutron scattering from dendrimer solutions is proposed. The mathematical description is given and the theoretical small-angle scattering curves for spherical sectors with different parameters are presented. It is shown that the model proposed is in good agreement with the experimental results. Comparison of the experimental small-angle neutron scattering curves for polyallylcarbosilane dendrimers of the ninth generation with model scattering curves suggests that the inner dendrimer sphere is permeable to a solvent whose density is lower than the density of the solvent beyond the dendrimer by a factor of at least 2

  11. Small angle neutron scattering study of disordered and crystalline iron nanoparticle assemblies

    International Nuclear Information System (INIS)

    Farrell, D.F.; Ijiri, Y.; Kelly, C.V.; Borchers, J.A.; Rhyne, J.J.; Ding, Y.; Majetich, S.A.

    2006-01-01

    Monodisperse surfactant-coated iron nanoparticles are used to form both disordered nanoparticle assemblies and ordered face-centered cubic nanoparticle crystals. The structural order is probed by small angle X-ray scattering, and the magnetic scattering is studied using small angle neutron scattering. The magnetic scattering corresponding to different length scales is interpreted in terms of collective correlations among the particles within the assemblies

  12. Survey of background scattering from materials found in small-angle neutron scattering.

    Science.gov (United States)

    Barker, J G; Mildner, D F R

    2015-08-01

    Measurements and calculations of beam attenuation and background scattering for common materials placed in a neutron beam are presented over the temperature range of 300-700 K. Time-of-flight (TOF) measurements have also been made, to determine the fraction of the background that is either inelastic or quasi-elastic scattering as measured with a 3 He detector. Other background sources considered include double Bragg diffraction from windows or samples, scattering from gases, and phonon scattering from solids. Background from the residual air in detector vacuum vessels and scattering from the 3 He detector dome are presented. The thickness dependence of the multiple scattering correction for forward scattering from water is calculated. Inelastic phonon background scattering at small angles for crystalline solids is both modeled and compared with measurements. Methods of maximizing the signal-to-noise ratio by material selection, choice of sample thickness and wavelength, removal of inelastic background by TOF or Be filters, and removal of spin-flip scattering with polarized beam analysis are discussed.

  13. Development of the time-of-flight smaller-angle neutron scattering instrument TAIKAN

    International Nuclear Information System (INIS)

    Suzuki, Jun-ichi; Takata, Shin-ichi; Shinohara, Takenao; Oku, Takayuki; Kira, Hiroshi; Suzuya, Kentaro; Aizawa, Kazuya; Arai, Masatoshi; Otomo, Toshiya; Sugiyama, Masaaki

    2010-01-01

    The technique of small-angle neutron scattering has been used to analyze structures of size between about 1 nm and 10 μm in materials and life science. This article introduces the development of the smaller-angle neutron scattering instrument 'TAIKAN' of MLF/J-PARC, which will provide opportunity for efficient structure analysis with high spatial- and time-resolution. (author)

  14. Small-Angle Neutron Scattering and Magnetization Study of HoNi2B2C

    OpenAIRE

    Ramazanoglu, M.; Laver, M.; Yagmurcu, A.; Choi, E. -M.; Lee, S. -I.; Knigavko, A.; Gaulin, B. D.

    2014-01-01

    The superconducting and magnetic properties of HoNi2B2C single crystals are investigated through transport, magnetometry and small-angle neutron scattering measurements. In the magnetic phases that enter below the superconducting critical temperature, the small-angle neutron scattering data uncover networks of magnetic surfaces. These likely originate from uncompensated moments e.g. at domain walls pinned to crystallographic grain boundaries. The field and temperature dependent behaviour appe...

  15. Resolution effects and analysis of small-angle neutron scattering data

    DEFF Research Database (Denmark)

    Pedersen, J.S.

    1993-01-01

    A discussion of the instrumental smearing effects for small-angle neutron scattering (SANS) data sets is given. It is shown that these effects can be described by a resolution function, which describes the distribution of scattering vectors probed for the nominal values of the scattering vector...

  16. Neutron Imaging of Laser Melted SS316 Test Objects with Spatially Resolved Small Angle Neutron Scattering

    Directory of Open Access Journals (Sweden)

    Adam J. Brooks

    2017-12-01

    Full Text Available A novel neutron far field interferometer is explored for sub-micron porosity detection in laser sintered stainless steel alloy 316 (SS316 test objects. The results shown are images and volumes of the first quantitative neutron dark-field tomography at various autocorrelation lengths, ξ . In this preliminary work, the beam defining slits were adjusted to an uncalibrated opening of 0.5 mm horizontal and 5 cm vertical; the images are blurred along the vertical direction. In spite of the blurred attenuation images, the dark-field images reveal structural information at the micron-scale. The topics explored include: the accessible size range of defects, potentially 338 nm to 4.5 μ m, that can be imaged with the small angle scattering images; the spatial resolution of the attenuation image; the maximum sample dimensions compatible with interferometry optics and neutron attenuation; the procedure for reduction of the raw interferogram images into attenuation, differential phase contrast, and small angle scattering (dark-field images; and the role of neutron far field interferometry in additive manufacturing to assess sub-micron porosity.

  17. Neutron scattering. Lectures

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2013-07-01

    The following topics are dealt with: Neutron sources, symmetry of crystals, nanostructures investigated by small-angle neutron scattering, structure of macromolecules, spin dependent and magnetic scattering, structural analysis, neutron reflectometry, magnetic nanostructures, inelastic neutron scattering, strongly correlated electrons, polymer dynamics, applications of neutron scattering. (HSI)

  18. Neutron scattering. Lectures

    International Nuclear Information System (INIS)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner

    2013-01-01

    The following topics are dealt with: Neutron sources, symmetry of crystals, nanostructures investigated by small-angle neutron scattering, structure of macromolecules, spin dependent and magnetic scattering, structural analysis, neutron reflectometry, magnetic nanostructures, inelastic neutron scattering, strongly correlated electrons, polymer dynamics, applications of neutron scattering. (HSI)

  19. A review on the study of polymer properties by Small Angle Neutron Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Baek Seok; Lee, Chang Hee; Sim, Hae Seop; Lee, Jung Sool [Korea Atomic Energy Research Institute, Daeduk (Korea, Republic of); Kim, Hong Doo [Kyunghee Univ., Seoul (Korea, Republic of); Kim, Eu Gene [Hongik Univ., Seoul (Korea, Republic of); Cha, Kuk Heon [Seoul National Univ., Seoul (Korea, Republic of)

    1998-05-01

    This report contains concept of small angle neutron scattering , various design features and considerations of the small angle neutron spectrometer at HANARO, and recent trends of polymer studies by using this SANS technique with the installation of the spectrometer in near future. We, therefore, wish to review feasibility of small angle studies for polymer field at this spectrometer and to help possible beam time users for their experimental consideration. (author). 23 refs., 7 tabs., 23 figs

  20. The resolution function of triple-axis neutron spectometers in the limit of small scattering angles

    International Nuclear Information System (INIS)

    Mitchell, P.W.; Cowley, R.A.; Higgins, S.A.

    1984-01-01

    The Copper-Nathans formulation of the resolution function of a triple-axis crystal spectrometer for neutron-scattering experiments gives a singular resolution matrix when the scattering angle is small. The origin of this singularity is discussed and an alternative derivation of the resolution matrix given which avoids this difficulty. The results are illustrated by numerical calculations for several typical experiments showing that resolution corrections may be large and very significant for experiments at small scattering angles. (Auth.)

  1. Nondestructive hydrogen analysis of steam-oxidized Zircaloy-4 by wide-angle neutron scattering

    Science.gov (United States)

    Yan, Yong; Qian, Shuo; Garrison, Ben; Smith, Tyler; Kim, Peter

    2018-04-01

    A nondestructive neutron scattering method to precisely measure the hydrogen content in high-temperature steam-oxidized Zircaloy-4 cladding was developed. Zircaloy-4 cladding was used to produce hydrided specimens with hydrogen content up to ≈500 wppm. Following hydrogen charging, the hydrogen content of the hydrided specimens was measured using the vacuum hot extraction method, by which the samples with desired hydrogen concentrations were selected for the neutron study. The hydrided samples were then oxidized in steam up to ≈6.0 wt. % at 1100 °C. Optical microscopy shows that our hydriding procedure results in uniform distribution of circumferential hydrides across the wall thickness, and uniform oxide layers were formed on the sample surfaces by the steam oxidation. Small- and wide-angle neutron scattering were simultaneously performed to provide a quick (less than an hour per sample) measurement of the hydrogen content in various types of hydrided and oxidized Zircaloy-4. Our study demonstrates that the hydrogen in pre-oxidized Zircaloy-4 cladding can be measured very accurately by both small- and wide-angle neutron scattering. For steam-oxidized samples, the small-angle neutron scattering is contaminated with coherent scattering from additional structural features induced by the steam oxidation. However, the scattering intensity of the wide-angle neutron scattering increases proportionally with the hydrogen charged in the samples. The hydrogen content and wide-angle neutron scattering intensity are highly linearly correlated for the oxidized cladding samples examined in this work, and can be used to precisely determine the hydrogen content in steam-oxidized Zircaloy-4 samples. Hydrogen contents determined by neutron scattering of oxidation samples were also found to be consistent with the results of chemical analysis within acceptable margins for error.

  2. Small-angle neutron scattering investigations of magnetic nanostructures and interfaces using polarized neutrons

    Science.gov (United States)

    Wiedenmann, Albrecht

    2001-03-01

    Using polarized neutrons, the relative contrasts for small-angle scattering are strongly modified which allows a precise evaluation of magnetization, density and composition profiles at surfaces and interfaces of nanoscaled materials. In Co ferrofluids, the magnetic core behaves as a non-interacting single domain. The core is encapsulated by a shell of surfactant molecules which was found to be impenetrable for the solvent. In soft magnetic Fe-Si-B-(Nb,Cu) and Fe-Nb-B alloys, the presence of a weak magnetic interface between ferromagnetic nanocrystals and amorphous matrix has been demonstrated which breaks the exchange interactions.

  3. Porosity determination in doped graphites using small-angle neutron scattering measurements

    Czech Academy of Sciences Publication Activity Database

    Mergia, K.; Stefanopoulos, K. L.; Martinez-Escandell, M.; Strunz, Pavel

    2012-01-01

    Roč. 340, č. 012102 (2012), s. 1-7 ISSN 1742-6588. [5th European Conference on Neutron Scattering . Praha, 17.07.2011-21.07.2011] Grant - others:European Commission(XE) 505925 Program:FP6 Institutional support: RVO:61389005 Keywords : doped graphites * porosity * small - angle neutron diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism

  4. Influence of multiple small-angle neutron scattering on diffraction peak broadening in ferritic steel

    Czech Academy of Sciences Publication Activity Database

    Woo, W.; Em, V.; Shin, E.; Mikula, Pavol; Ryukhtin, Vasyl

    2015-01-01

    Roč. 48, APR (2015), s. 350-356 ISSN 0021-8898 R&D Projects: GA ČR GB14-36566G; GA MŠk(CZ) LM2011019 Institutional support: RVO:61389005 Keywords : peak broadening * small-angle neutron scattering * neutron diffraction * magnetic domain Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.720, year: 2014

  5. The use of multichannel collimation in small-angle neutron scattering a computer-simulation study

    CERN Document Server

    Falcao, A N; Carvalho, F G

    2002-01-01

    A Monte Carlo computer simulation was performed to evaluate the use of converging multichannel collimation in a small-angle neutron-scattering arrangement, giving guidelines for the construction of a first prototype. The neutron-absorbing efficiency as well as the divergence of the incoming beam were taken as parameters. Results show that the use of converging multichannel collimation in a small-angle neutron-scattering instrument leads, for the same experimental resolution, to very high count-rate gains over the typical single-channel-collimator instrument. (orig.)

  6. The use of multichannel collimation in small-angle neutron scattering: a computer-simulation study

    International Nuclear Information System (INIS)

    Falcao, A.N.; Margaca, F.M.A.; Carvalho, F.G.

    2002-01-01

    A Monte Carlo computer simulation was performed to evaluate the use of converging multichannel collimation in a small-angle neutron-scattering arrangement, giving guidelines for the construction of a first prototype. The neutron-absorbing efficiency as well as the divergence of the incoming beam were taken as parameters. Results show that the use of converging multichannel collimation in a small-angle neutron-scattering instrument leads, for the same experimental resolution, to very high count-rate gains over the typical single-channel-collimator instrument. (orig.)

  7. A holder to rotate sample cells to avoid sedimentation in small-angle neutron scattering and ultra small-angle neutron scattering experiments

    International Nuclear Information System (INIS)

    Olsson, Anders; Hellsing, Maja S; Rennie, Adrian R

    2013-01-01

    Sedimentation, or creaming, of samples can significantly alter the amount of material in the beam during small-angle scattering experiments. Simple rotating mounts that ameliorate this effect are described and the design criteria are carefully discussed. A modular design permits simple adaptation to various instruments and different sample cells. Temperature control in the range 10 °C below ambient to about +40 °C has been implemented using air flow and a Peltier device. Example ultra small-angle neutron scattering data are shown that exploit the simplicity of the mounts and the capability to position several samples close together on a translation stage. (paper)

  8. Small-Angle Neutron Scattering Study of Structural Changes in Temperature-Sensitive Microgel Colloids

    NARCIS (Netherlands)

    Stieger, M.A.; Richtering, W.; Pedersen, J.S.; Lindner, P.

    2004-01-01

    The structure of temperature-sensitive poly(N-isopropylacrylamide) microgels in dilute suspension was investigated by means of small-angle neutron scattering. A direct modeling expression for the scattering intensity distribution was derived which describes very well the experimental data at all

  9. Small-angle neutron-scattering studies of the magnetic phase diagram of MnSi

    DEFF Research Database (Denmark)

    Harris, P.; Lebech, B.; Hae Seop Shim

    1995-01-01

    The antiferromagnetic order of MnSi has been studied as function of temperature and applied magnetic field using small-angle neutron scattering. The results were analyzed using the three-dimensional resolution function and the scattering cross-section to model the diffraction data. Physical...

  10. Small-angle thermal neutron scattering of hen egg-white lysozyme in aqueous solution

    International Nuclear Information System (INIS)

    Sangawa, U.; Niimura, N.

    1992-01-01

    A small-angle neutron scattering measurement was done for a lysozyme sample in aqueous solutions with different D 2 O/H 2 O ratios. Structure parameters such as R gc , α and β and the scattering functions such as I c (Q), I s (Q) and I cs (Q) were obtained. (orig.)

  11. Ultra small angle neutron scattering from amorphous Ni-Pd-P-alloys

    International Nuclear Information System (INIS)

    Hagenmayer, R.M.; Zeyen, C.M.E.; Lamparter, P.; Steeb, S.

    1993-01-01

    Using a neutron double crystal spectrometer, thin amorphous Ni-Pd-P-samples were investigated at very small Q-values (10 -5 A -1 ≤ Q ≤ 10 -3 A -1 ). The immersion method shows that the small angle scattering effect is mainly caused by surface scattering. (orig.)

  12. Performance of a new small-angle neutron scattering instrument at the Malaysian TRIGA reactor

    International Nuclear Information System (INIS)

    Sufi, M.A.M.; Radiman, S.; Wiedenmann, A.; Mortensen, K.

    1997-01-01

    The set-up and alignment of a new small-angle neutron scattering (SANS) instrument, installed at the 1 MW light-water-moderated MINT TRIGA research reactor, are described. The wavelength distribution and the flux at the sample position have been determined. First neutron scattering measurements were made on two reference samples with strong scattering power; the results prove that the SANS signal is well reproduced on the instrument when samples of typical size are used, despite the high level of the background of fast and epithermal neutrons. (orig.)

  13. Neutron and x-ray small angle scattering of biological molecules

    International Nuclear Information System (INIS)

    Borso, C.S.; Danyluk, S.S.; Williamson, F.S.; Holmblad, G.L.; DeJong, S.; Pohl, J.

    1981-01-01

    The objectives of this project are to develop instrumentation for small angle x-ray and neutron scattering, and to utilize small angle techniques for study of the structures of the intracellular molecules interacting with the secondary messengers involved in cellular regulation. A unique self-scanning photodiode array has been developed as a linear position sensitive detector for studies of biological structures. A time-of-flight (TOF) small angle neutron instrument was developed and successfully tested at the prototype pulsed neutron facility, ZING-P'. Considerable hardware and software developments were necessary to successfully demonstrate the prototype small angle neutron scattering instrument. A dedicated data acquisition system based on a microprocessor was developed and tested within the short period of approximately 6 months and was interfaced to a biological sample changer and environmental controller. The resolution of the tapered collimation system proved to be adequate

  14. Neutron scattering. Lectures

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2010-07-01

    The following topics are dealt with: Neutron sources, symmetry of crystals, diffraction, nanostructures investigated by small-angle neutron scattering, the structure of macromolecules, spin dependent and magnetic scattering, structural analysis, neutron reflectometry, magnetic nanostructures, inelastic scattering, strongly correlated electrons, dynamics of macromolecules, applications of neutron scattering. (HSI)

  15. Neutron scattering. Lectures

    International Nuclear Information System (INIS)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner

    2010-01-01

    The following topics are dealt with: Neutron sources, symmetry of crystals, diffraction, nanostructures investigated by small-angle neutron scattering, the structure of macromolecules, spin dependent and magnetic scattering, structural analysis, neutron reflectometry, magnetic nanostructures, inelastic scattering, strongly correlated electrons, dynamics of macromolecules, applications of neutron scattering. (HSI)

  16. Scattering studies of large scale structures at the ultra small angle neutron scattering instrument S18

    Science.gov (United States)

    Hainbuchner, M.; Baron, M.; Lo Celso, F.; Triolo, A.; Triolo, R.; Rauch, H.

    2002-02-01

    In recent years ultra small angle neutron scattering (USANS) has developed into a powerful standard method for large scale structure investigations. The upgraded instrument S18 at the ILL's 58 MW high flux reactor is operated routinely with increasing beam time demand. The performance of the instrument and its abilities will be discussed in this paper. A peak to background ratio better than 10 5 is reached using Agamalian's tail reduction method. A q-range from 2.10 -5 up to 5.10 -2 Å-1 can be covered. This allows a clear overlap with standard pinhole SANS instruments. The new way collecting scattering data logarithmically equidistant in q-space saves measuring time. This allows measuring times of about 1.5 h for strong scattering specimens with reasonable statistics. We will present an overview of recent experiments which have been performed in co-operation with different groups from the international user community. This work comprises of structure investigations of petroliferous sedimentary rocks showing fractal scattering behaviour and time resolved USANS studies of the dynamics of hydration of cement paste. Concerning soft matter structures, Pirelli rubber nanocomposites have been investigated. In addition, time resolved measurement on a D 2O solution of a PPO-PEO-PPO block copolymer (Reverse Pluronic 25R5) and the dynamics of phase separation of methyl-hydroxy-propyl cellulose (MHPC) have been studied using a sample temperature control system.

  17. Vibrating phase echo concept for small-angle inelastic neutron scattering

    International Nuclear Information System (INIS)

    Michalec, R.

    1989-01-01

    Small-angle inelastic neutron scattering measurements are based on the vibrating phase echo concept. The double neutron diffraction is carried out by two thin vibrating single crystals, for example Si or Ge. The neutron beam diffracted at the monochromator crystal M is modulated with a frequency 2 Ω, where Ω is the circular frequency of the ultrasonic transducer. The second crystal A (analyser) vibrates at a frequency Ω with a phase shift φ. A neutron spectrometer on the basis of two vibrating single crystals is suitable within the scattering angle range 0.5' ≤ θ ≤ 50' and within the range of magnitude of the scattering vector Q = (2 to 500) x 10 -3 nm -1 . The described equipment covers the Q values of major part of the classical optical spectroscopy as well as Q values of part of the spin echo spectroscopy

  18. Characterization of nano-structure by small-angle X-ray and neutron scattering

    International Nuclear Information System (INIS)

    Ohnuma, Masato

    2017-01-01

    This paper outlines the cases when small-angle X-ray scattering method and small-angle neutron scattering method in transmission arrangement were applied to heterogeneity with low-volume rate (10% or below), such as nano-sized deposits and trace defects. In particular, it explains not only general analysis, but also the possibility of use of the small angle scattering method as a simple inspection method in nanostructure evaluation, as well as correspondence of small-angle scattering method with powder diffraction method in crystal structure evaluation. From the small-angle scattering profiles of a series of sample groups, we can judge which sample has the smallest nanostructure, by only comparing profiles without analysis. The object to be measured is a heterogeneous structure (void, second phase, crack, etc.) having a diameter of about 1 to several hundred nm present in a material. This paper also outlines the usual small-angle scattering analysis method, as well as further analysis using the difference between X-ray and neutron on scattering length contrast. (A.O.)

  19. The application of ultra-small-angle neutron scattering in material research

    International Nuclear Information System (INIS)

    Peng Mei; Chen Liang; Sun Liangwei

    2011-01-01

    Material researches by use of Ultra-small-angle neutron scattering (USANS) have to be introduced, including experiments have to be carried in polymer science, fractal geometry of rocks, multiplex, complex fluids, hydrogels, artificial lattices, metal materials and high energy materials etc. It is show that, in addition to traditional small-angle-neutron scattering (SANS) techniques and so on, more comprehensive information of inner structure of materials can be acquired when combined with USANS, and this offer important help to resolve some material science problems. (authors)

  20. Phase separation and ordering process in Al-Li alloys studied by small-angle neutron scattering and neutron diffraction

    International Nuclear Information System (INIS)

    Furusaka, M.; Fujikawa, S.I.

    1993-01-01

    To study phase separation kinetics of Al-9.5at.%Li polycrystalline alloys in which precipitates have ordered Al 3 Li (δ') structure, profile analysis of small-angle neutron scattering and superlattice reflections (100) and (110) were done. A small-angle scattering instrument and a triple-axis spectrometer in elastic mode were used in the measurements. Strong texture was observed in the reflections. Therefore, measurements were done using the crystal orientation where the intensity of the reflection was at the maximum. Profiles of small-angle scattering and superlattice reflections were almost identical at higher momentum transfer side. At lower momentum transfer side, small-angle scattering showed interference effects, but superlattice reflection did not show any sign of interference. Integrated intensities of superlattice reflections were obtained and compared with small-angle scattering intensity. The order parameter was not saturated in the δ' precipitates at the early stage of the phase separation process

  1. Neutron Reflectometry and Small Angle Neutron Scattering of ABC Miktoarm Terpolymer Thin-Films

    Science.gov (United States)

    Arras, Matthias M. L.; Wang, Weiyu; Mahalik, Jyoti P.; Hong, Kunlun; Sumpter, Bobby G.; Smith, Gregory S.; Chernyy, Sergey; Kim, Hyeyoung; Russell, Thomas P.

    Due to the constraint of the junction point in miktoarm terpolymers, where three chains meet, ABC miktoarm terpolymers are promising to obtain nanostructured, long-range ordered materials. We present details of the thin-film structure of ABC miktoarm terpolymers in the poly(styrene), poly(isoprene), poly(2-vinylpyridine) (PS-PI-P2VP) system, investigated by neutron reflectometry and small angle neutron scattering. To this end, we synthesized partially deuterated versions of the PS-PI-P2VP and investigated annealed samples, spin-coated to various thicknesses of the bulk repeat period. Furthermore, we investigated the structural change upon selective blending with homopolymers or fullerenes. We find that thin-film constraints on the morphology can vanish after only twice the repetition period. In addition, it is indicated that nanoparticles improve the ordering in these systems, however, this seems to be not necessarily true for homopolymer blending. This research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory.

  2. Neutron analyses for nuclear materials: texture, residual stresses and small angle scattering

    International Nuclear Information System (INIS)

    Bechade, J.L.; Carlan, Y. de; Mathon, M.H.

    2015-01-01

    Neutron techniques are very useful for metallurgical investigations of nuclear materials, bringing complementary results compared to others analysis techniques like XRD, TEM, APT. Especially, statistical information representative of the bulk material are obtained. In the first part of this article we recall the theoretical principles of neutron diffraction techniques and of the small angle neutron scattering technique (SANS). In the second part we review examples of neutron applications for texture measurements, stress determination and the microstructural characterisation by SANS, particularly for 2 main components of nuclear reactors: the pressure vessel (welding and base metal) and the fuel cladding

  3. Intercalibration of small-angle X-ray and neutron scattering data

    International Nuclear Information System (INIS)

    Russell, T.P.; Lin, J.S.; Spooner, S.; Wignall, G.D.

    1988-01-01

    Absolute calibration forms a valuable diagnostic tool in small-angle scattering experiments and allows the parameters of a given model to be restricted to the set which reproduces the observed intensity. General methods which are available for absolute scaling of small-angle X-ray scattering (SAXS) data are reviewed along with estimates of the degree of internal consistency which may be achieved between the various standards. In order to minimize the time devoted to calibration in a given experimental program, emphasis is placed on developing a set of precalibrated strongly scattering standards for the SAXS facilities of the National Center for Small-Angle Scattering Research (Oak Ridge). Similar standards have been developed previously for calibration of small-angle neutron scattering (SANS) data. Particular attention is given to standards which can be used for either SAXS or SANS experiments where each sample has been independently calibrated for both types of radiation. These calibrations have been tested via the theoretical relationships between the two cross sections. It has been found that specimens best suited for such intercalibration purposes are a glassy carbon specimen where the scattering arises from voids in a carbon matrix and a perdeuterated polyethylene where the scattering arises from periodic arrangement of the crystalline lamellae. In only these two cases could the identical specimen be used for both the neutron and X-ray scattering experiments. (orig.)

  4. Measurement of small-angle elastic scattering cross sections of fast neutron

    International Nuclear Information System (INIS)

    Wan Dairong; Dai Yunsheng; Liang Xuecai; Cao Jianhua

    1993-11-01

    A position-sensitive detector has been developed for studying small angle scattering of fast neutrons. The detector mainly consists of two photomultiplier tubes to monitor the liquid scintillator. The time difference between two signals from two photomultiplier tubes is used to determine the position of light emitted. The 14.7 MeV neutron elastic scattering differential cross section of Zr, Nb, Ti and Pb were measured by position-sensitive detector and associated particle time-of-flight method at the angles from 3 deg to 15 deg. The corrections for neutron fluence attenuation, multiple scattering and finite geometry are performed by using Monte-Carlo method. The experimental results provide data needed in nuclear engineering design

  5. Small angle neutron scattering on the matters radiated by impulse plasma flows

    International Nuclear Information System (INIS)

    Ibraev, B.; Baimbetov, F.; Treimer, W.

    1999-01-01

    Complete text of publication follows. By methods of small angle neutron scattering (neutron wavelength ∼ 0.478 nm) on two-crystal diffractometer the structural inhomogenities (defects, clusters, pores, etc.) were investigated. The inhomogenities were produced by the impulse hydrogen and nitride plasma flows on the surface of steel 12X18H10T, aluminum alloy Al-Cu-Mg and graphite. The energy density of plasma was varied from 0 to 120 J/cm 2 . The values of total macroscopic scattering cross-section in dependence of radiation dose significantly change. It reveals the structural transformations on the samples' surface due to plasma influence. The critical doses for the given types of samples, that determine start of the change of physical and mechanical properties, were calculated. Theoretical calculations and the small angle neutron scattering data are in good agreement as well as the experimental data obtained by electron microscopy and metallography measurements. (author)

  6. Structural characterizaton of deep-submicron lithographic structures using small-angle neutron scattering

    Science.gov (United States)

    Lin, Eric K.; Jones, Ronald L.; Wu, Wen-li; Barker, John G.; Bolton, Patrick J.; Barclay, George G.

    2002-07-01

    As critical dimensions continue to decrease with each technology node, the precise characterization of line width and profile becomes an increasingly challenging task. Small angle neutron scattering (SANS) offers several advantages for the characterization of sub-100 nm structures, particularly as a calibrating measurement method. In this work, SANS is used to characterize three samples prepared with the same mask and focus conditions, but different photoresist formulations. The mask pattern consists of parallel lines with a nominal line width of 180 nm and a 1:2 line to space ratio. Scattering data are taken using both a focused neutron beam instrument (two-dimensional data) and a perfect crystal diffraction ultra-high resolution small angle neutron scattering (USANS) instrument. From the location and intensity of observed diffraction peaks, both the periodicity of each grating pattern and the average line widths are determined from simple analytic expressions with nanometer resolution.

  7. Small angle scattering of X radiation and slow neutrons in structural analyses of amorphous solids

    International Nuclear Information System (INIS)

    Kostorz, G.

    1980-01-01

    Small angle scattering of x radiation and slow neutrons allows to detect inhomogeneities of the dimension of ten to some thousands of Angstroem by the difference in the scattering length density. The progress made during recent years in the development of apparatusses has created the possibility of solving very complicated problems. A first outline shows that in separation processes as well as in investigating extended defects the method of small angle scattering may provide valuable contributions to the analysis of the non-crystalline state

  8. Collimation effects in small-angle X-ray and neutron scattering

    International Nuclear Information System (INIS)

    Schmidt, P.W.

    1988-01-01

    To obtain adequate intensity in small-angle X-ray and neutron scattering measurements, the apertures that define the incident and scattered beams often must be made so large that the measured intensity is an average over an appreciable interval of scattering angles. Allowance must frequently be made for the resulting distortion of the measured scattering curve. A technique previously developed by Hendricks and Schmidt for describing collimation effects is outlined. This method makes use of a function called the ''weighting function'', which specifies the width of the interval over which the intensity is averaged and indicates the emphasis given to scattering angles within this interval. A new calculation of the weighting function for pinhole collimating systems, which employ circularly symmetric apertures instead of long narrow slits, is presented. Several techniques for performing collimation corrections are described, and a review is given of results that several workers have recently obtained in studies of collimation effects in pinhole systems. (orig.)

  9. Small-angle neutron scattering instrumentation at the Australian replacement research reactor

    International Nuclear Information System (INIS)

    Gilbert, E.

    2003-01-01

    Full text: A small-angle neutron scattering instrument is being designed as part of the initial instrument suite for the 20 MW Australian Replacement Research Reactor. The proposed 40 m long instrument will receive neutrons from a large liquid-D 2 cold source, use a 1 m 2 detector, have incident beam polarisation and will have provision for polarisation analysis. Scheduled for completion in January 2006, the conceptual details of the new SANS instrument are presented

  10. High temperature furnaces for small and large angle neutron scattering of disordered materials

    International Nuclear Information System (INIS)

    Bletry, J.; Taverniere, P.; Senillou, C.; Desre, P.; Maret, M.; Chieux, P.

    1984-01-01

    Two similar high temperature furnaces (up to 2000 0 C) have been developed for large angle and small angle neutron scattering (SANS) experiments respectively. They are vacuum furnaces with a thin tungsten foil heating element supplied by two tantalum leads, and shielded by thin tungsten foils maintained in a tantalum box. In a neutron beam, the furnaces produce a very low scattering level (without any Bragg peaks) due to the openings in the heating element, the shields and the tantalum box for the incident, unscattered beam and the scattered beam at low angles. Thus the furnace absorption correction is also much easier. A platinum thermocouple controls temperature, very high temperatures are measured optically. A vacuum chamber has been especially designed for SANS experiments with two windows in polished sapphire. The furnaces have been successfully used for the study of liquid alloys on the D4, D11 and D17 spectrometers at the ILL

  11. Reversible membrane reorganizations during photosynthesis in vivo: revealed by small-angle neutron scattering

    DEFF Research Database (Denmark)

    Nagy, Gergely; Posselt, Dorthe; Kovacs, Laszlo

    2011-01-01

    In the present study, we determined characteristic repeat distances of the photosynthetic membranes in living cyanobacterial and eukaryotic algal cells, and in intact thylakoid membranes isolated from higher plants with time-resolved small-angle neutron scattering. This non-invasive technique rev...

  12. Small-angle neutron and dynamic light scattering study of gelatin ...

    Indian Academy of Sciences (India)

    The state of intermolecular aggregates and that of folded gelatin molecules could be characterized by dynamic laser light and small-angle neutron scattering ... School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110 067, India; Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 ...

  13. Informing the improvement of forest products durability using small angle neutron scattering

    Science.gov (United States)

    Nayomi Plaza Rodriguez; Sai Venkatesh Pingali; Shuo Qian; William T. Heller; Joseph E. Jakes

    2016-01-01

    A better understanding of how wood nanostructure swells with moisture is needed to accelerate the development of forest products with enhanced moisture durability. Despite its suitability to study nanostructures, small angle neutron scattering (SANS) remains an underutilized tool in forest products research. Nanoscale moisture-induced structural changes in intact and...

  14. A small angle neutron scattering study on the mixtures of pluronic ...

    Indian Academy of Sciences (India)

    cO Indian Academy of Sciences. Vol. 71, No. 5. — journal of. November 2008 physics pp. 1063–1067. A small angle neutron scattering study on the mixtures of pluronic L121 and anionic surfactant AOT. G GHOSH1,∗, V K ASWAL2 and D VARADE3. 1UGC-DAE Consortium for Scientific Research, Mumbai 400 085, India.

  15. Small-angle neutron scattering study of sodium cholate and sodium ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Small angle neutron scattering (SANS) measurements of D2O solutions. (0⋅1 M) of sodium cholate (NaC) and sodium deoxycholate (NaDC) were carried out at T = 298 K. Under compositions very much above the critical micelle concentration. (CMC), the bile salt micelle size growths were monitored by adopting ...

  16. Small angle neutron scattering study on a phase separation in a 3-component microemulsion system

    DEFF Research Database (Denmark)

    Seto, H.; Yokoi, E.; Komura, S.

    1993-01-01

    observed a small change of the water droplet size approaching a phase separation point. In this work, further small angle neutron scattering results are presented obtained at the new SANS equipment in JAERI. The evidences described above were confirmed and a detailed phase diagram has been obtained...

  17. Structure in cohesive powder studied with spin-echo small angle neutron scattering

    NARCIS (Netherlands)

    Andersson, R.; Bouwman, W.G.; Luding, Stefan; de Schepper, I.M.

    2008-01-01

    Extracting structure and ordering information from the bulk of granular materials is a challenging task. Here we present Spin-Echo Small Angle Neutron Scattering Measurements in combination with computer simulations on a fine powder of silica, before and after uniaxial compression. The cohesive

  18. Structure in cohesive powders studied with spin-echo small angle neutron scattering

    NARCIS (Netherlands)

    Andersson, R.; Bouwman, W.G.; Luding, S.; De Schepper, I.M.

    2008-01-01

    Extracting structure and ordering information from the bulk of granular materials is a challenging task. Here we present Spin-Echo Small Angle Neutron Scattering Measurements in combination with computer simulations on a fine powder of silica, before and after uniaxial compression. The cohesive

  19. A high-temperature furnace for small-angle neutron scattering

    International Nuclear Information System (INIS)

    Jal, J.F.; Guiraud, G.; Chieux, P.; Dupuy, J.

    1977-01-01

    A high temperature furnace (T 0 C) has been developed for small-angle neutron scattering experiments in the range of momentum transfer above 0.2 nm -1 . It is especially suited for the study of highly corrosive liquids such as alkali-alkali-halide mixtures. It allows critical fluctuations near liquid-liquid miscibility gaps to be investigated. (author)

  20. Small-angle neutron scattering: a tool for microstructural investigation of high-temperature materials

    Czech Academy of Sciences Publication Activity Database

    Strunz, Pavel; Mukherji, D.; Gilles, R.; Rösler, J.; Wiedenmann, A.

    2003-01-01

    Roč. 426, č. 4 (2003), s. 755-760 ISSN 0255-5476 R&D Projects: GA AV ČR KSK1010104 Keywords : small-angle neutron scattering * superalloys Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.602, year: 2003

  1. Investigation of metallic and ceramic materials by small-angle neutron scattering

    NARCIS (Netherlands)

    Smirnov, YI; Elyutin, NO

    Small-angle neutron scattering measurements on a double-crystal spectrometer with perfect monochromator and analyzer crystals were used to follow microstructural changes in the aluminum alloy VD-17. refractory alloy ZhS-6, and dispersion-hardened zirconia-based ceramics with yttria additions. The

  2. The aggregation behavior of zinc-free insulin studied by small-angle neutron scattering

    DEFF Research Database (Denmark)

    Pedersen, J.S.; Hansen, S.; Bauer, R.

    1994-01-01

    The aggregation behavior of zinc-free insulin has been studied by small-angle neutron scattering as a function of pH and ionic strength of the solution. The pair distance distribution functions for the 12 samples have been obtained by indirect Fourier transformation. The results show......-particle correlation effects, were obtained by an indirect Fourier transformation, omitting the data at small scattering vectors, which are influenced by these effects. By this procedure the weight-averaged molecular mass and the average radius of gyration were determined. These parameters vary from 1.3 times...... to an equilibrium model recently introduced by Kadima et al. (1993). The neutron scattering results agree well with the predictions of this model except that broader mass distributions are suggested by neutron scattering....

  3. Small-angle neutron scattering study of Fe-B and Fe-Ni-B metallic glasses

    International Nuclear Information System (INIS)

    Cser, L.; Kovacs, I.; Lovas, A.; Svab, E.; Zsigmond, G.

    1982-01-01

    Small-angle scattering of neutron (SANS) was analysed on Fe-B and Fe-Ni-B metallic glass ribbons by means of a double crystal small angle device and a neutron diffractometer. The dimensions of magnetic domains and small clusters were determined. An appreciable anisotropy of SANS intensity and surface scattering was observed. (orig.)

  4. Small-angle neutron scattering study of Fe-B and Fe-Ni-B metallic glasses

    International Nuclear Information System (INIS)

    Cser, L.; Kovacs, I.; Lovas, A.; Svab, E.; Zsigmond, Gy.

    1981-01-01

    Small-angle neutron scattering (SANS) on Fe-B and Fe-Ni-B metallic glass ribbons was analysed by means of a double-crystal small-angle device and a neutron diffractometer. The sizes of magnetic domains and small clusters were determined. An appreciable anisotropy of SANS intensity and surface scattering was observed. (author)

  5. Magnetic nanostructures in FeNbB studied by small-angle neutron scattering

    Science.gov (United States)

    Marcin, J.; Wiedenmann, A.; Škorvánek, I.

    2000-03-01

    The evolution of nuclear and magnetic microstructure during crystallization of amorphous FeNbB alloys at temperatures between 450°C and 510°C is investigated by a small-angle neutron scattering (SANS). From the nuclear and magnetic scattering the corresponding size distributions of BCC-Fe nanocrystals are determined. The average radius of the magnetized core of BCC-Fe grains has been found to be smaller in comparison with the size of nanograins itself.

  6. New Insights into Pore Characteristics and Hydrocarbon Generation of Shale Using Small-Angle Neutron Scattering

    Science.gov (United States)

    Ding, M.; Hartl, M.; Wang, Y.; Hjelm, R.

    2014-12-01

    Pore size, distribution, connectivity, and shape as well as hydrocarbon saturation and composition reflect the history of hydrocarbon maturation and migration. However, characterization of the underlying factors and processes controlling hydrocarbons behavior in tight rocks is extremely limited, especially lacking of direct experimental observations. We have studied the pore characteristics of marine and lacustrine shale from the Erdos basin, China during laboratory pyrolysis using small-angle neutron scattering (SANS). Our SANS results show that scattering intensity of smaller pores (industry.

  7. Time-resolved small-angle neutron scattering study on soap-free emulsion polymerization

    International Nuclear Information System (INIS)

    Motokawa, Ryuhei; Koizumi, Satoshi; Hashimoto, Takeji; Nakahira, Takayuki; Annaka, Masahiko

    2006-01-01

    We investigated an aqueous soap-free emulsion polymerization process of Poly(N-isopropylacrylamide)-block-poly(ethylene glycol) by ultra-small-angle and time-resolved small-angle neutron scattering methods. The results indicate that the compartmentalization of chain end radicals into solid-like micelle cores crucially leads to the quasi-living behavior of the radical polymerization by prohibiting recombination process

  8. Polarized small-angle neutron scattering (SANSPOL) for discrimination of nano sized components in ferro fluids

    International Nuclear Information System (INIS)

    Heinemann, A.; Wiedenmann, A.; Kammel, M.; Hoell, A.

    2003-01-01

    The use of polarized neutron technique in small-angle scattering (SANS) have led to new results in the case of magnetic nanometer-scale structure analysis. Different magnetic cross sections for spin-up and spin-down neutron scattering can be combined with chemical contrast variation methods. We show that the analysis of the interference term of nuclear and magnetic scattering respectively enables the extraction of additional information on the composition and magnetization profiles of the samples. This technique profits by the clear distinction between the magnetic and nonmagnetic scattering contributions and the strong auxiliary conditions for model fitting procedures. Beside general formulas for some special cases of present experimental interest, we apply the approach to cobalt bases ferro fluid scattering data obtained in the HMI-V4 experiment. (authors)

  9. Improved performances of 36 m small-angle neutron scattering spectrometer BATAN in Serpong Indonesia

    International Nuclear Information System (INIS)

    Putra, Edy Giri Rachman; Bharoto; Santoso, Eddy; Ikram, Abarrul

    2009-01-01

    SMARTer, a 36 m small-angle neutron scattering (SANS) spectrometer owned by the National Nuclear Energy Agency of Indonesia (BATAN) was installed at the Neutron Scattering Laboratory (NSL) in Serpong, Indonesia. Lots of works on replacing, upgrading and improving the control system, experimental methods, data collection and reduction in the last two years have been carried out to optimize the performance of SMARTer. Some standard samples such as silver behenate, monodisperse polystyrene nanoparticle, porous silica and block copolymer PS-PEP film were measured for the inter-laboratory comparison.

  10. Micromagnetic simulation of magnetic small-angle neutron scattering from two-phase nanocomposites

    International Nuclear Information System (INIS)

    Michels, Andreas; Erokhin, Sergey; Berkov, Dmitry; Gorn, Nataliya

    2014-01-01

    The recent development of a micromagnetic simulation methodology—suitable for multiphase magnetic nanocomposites—permits the computation of the magnetic microstructure and of the associated magnetic small-angle neutron scattering (SANS) cross section of these materials. In this review we summarize results on the micromagnetic simulation of magnetic SANS from two-phase nanocomposites. The decisive advantage of this approach resides in the possibility to scrutinize the individual magnetization Fourier contributions to the total magnetic SANS cross section, rather than their sum, which is generally obtained from the experiment. The procedure furnishes unique and fundamental information regarding magnetic neutron scattering from nanomagnets

  11. Micromagnetic simulation of magnetic small-angle neutron scattering from two-phase nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Michels, Andreas, E-mail: andreas.michels@uni.lu [Physics and Materials Science Research Unit, University of Luxembourg, 162A Avenue de la Faïencerie, L-1511 Luxembourg (Luxembourg); Erokhin, Sergey; Berkov, Dmitry; Gorn, Nataliya [INNOVENT Technology Development, Prüssingstraße 27B, D-07745 Jena (Germany)

    2014-01-15

    The recent development of a micromagnetic simulation methodology—suitable for multiphase magnetic nanocomposites—permits the computation of the magnetic microstructure and of the associated magnetic small-angle neutron scattering (SANS) cross section of these materials. In this review we summarize results on the micromagnetic simulation of magnetic SANS from two-phase nanocomposites. The decisive advantage of this approach resides in the possibility to scrutinize the individual magnetization Fourier contributions to the total magnetic SANS cross section, rather than their sum, which is generally obtained from the experiment. The procedure furnishes unique and fundamental information regarding magnetic neutron scattering from nanomagnets.

  12. The small and wide angle neutron scattering instrument TAIKAN at J-PARC

    International Nuclear Information System (INIS)

    Takata, Shin-ichi; Shinohara, Takenao; Oku, Takayuki; Inamura, Yasuhiro; Nakatani, Takeshi; Suzuya, Kentaro; Aizawa, Kazuya; Arai, Masatoshi; Suzuki, Jun-ichi; Ohishi, Kazuki; Iwase, Hiroki; Tominaga, Taiki; Ito, Takayoshi; Otomo, Toshiya; Sugiyama, Masaaki

    2014-01-01

    The small and wide angle neutron scattering instrument (TAIKAN) is designed to cover the wide q range of 0.0005neutrons with the wavelength range of 0.5<λ<7.8Å and five detector banks which are small-, middle-, high-, ultra-small-angle, and backward detector banks. In this paper, the status of detector installation and data reduction method are presented. In addition, the instrument performance on the wide q-range measurement with high q-resolution is discussed with experimental results of two standard samples, a glassy carbon and a silver behenate. (author)

  13. Small-angle neutron scattering in materials science: Recent practical applications

    Science.gov (United States)

    Melnichenko, Yuri B.; Wignall, George D.

    2007-07-01

    Modern materials science and engineering relies increasingly on detailed knowledge of the structure and interactions in "soft" and "hard" materials, but there have been surprisingly few microscopic techniques for probing the structures of bulk samples of these substances. Small-angle neutron scattering (SANS) was first recognized in Europe as a major technique for this purpose and, over the past several decades, has been a growth area in both academic and industrial materials research to provide structural information on length scales ˜10-1000Å (or 1-100nm). The technique of ultrahigh resolution small-angle neutron scattering (USANS) raises the upper resolution limit for structural studies by more than two orders of magnitude and (up to ˜30μm) and hence overlaps with light scattering and microscopy. This review illustrates the ongoing vitality of SANS and USANS in materials research via a range of current practical applications from both soft and hard matter nanostructured systems.

  14. The design of a constant wavelength ultra small angle neutron scattering spectrometer

    International Nuclear Information System (INIS)

    Peng Mei; Chen Liang; Chen Yanzhou; Sun Liangwei

    2012-01-01

    In order to carry out the research of constant wavelength ultra small angle neutron scattering spectrometer (USANS), the design principle is studied in this paper base on relevant information from international laboratories. The main components are designed and calculated by using the Simres and NOP codes, and analytic method. The channel-cut crystal for monochromator and analyzer, and the pre-monochromator are designed, and minimum Q of spectrometer is calculated. The results indicate that width of Darwin plat affects the minimum Q of spectrometer, the angle resolution of reflectivity planes selected in the design can ensure a Q resolution in 10 -5 order. After the monochromatic neutron guide, a vertical focus monochromator does not seem to increase neutron flux at the sample stage, to simplify the monochromator structure and its manufacturing process, we propose to use un-focus pre-monochromator after the monochromatic neutron guide. (authors)

  15. Low-angle polarized neutron and X-ray scattering from magnetic nanolayers and nanostructures

    CERN Document Server

    Paul, Amitesh

    2017-01-01

    This research monograph presents the latest results related to the characterization of low dimensional systems. Low-angle polarized neutron scattering and X-ray scattering at grazing incidence are used as the two main techniques to explore various physical phenomena of these systems. Special focus is put on systems like thin film transition metal and rare-earth layers, oxide heterostructures, hybrid systems, self-assembled nanostructures and self-diffusion.  Readers will gain in-depth knowledge about the usage of specular scattering and off-specular scattering techniques. Investigation of in-plane and out-of-plane structures and magnetism with vector magnetometric information is illustrated comprehensively. The book caters to a wide audience working in the field of nano-dimensional magnetic systems and the neutron and X-ray reflectometry community in particular.

  16. Grazing incidence small-angle neutron scattering-an advanced scattering technique for the investigation of nanostructured polymer films

    Science.gov (United States)

    Müller-Buschbaum, P.; Gutmann, J. S.; Cubitt, R.; Petry, W.

    2004-07-01

    With grazing incidence small-angle neutron scattering (GISANS), the limitations of conventional small-angle neutron scattering with respect to extremely small sample volumes in the thin-film geometry are overcome. GISANS turned out to be a powerful advanced scattering technique for the investigation of nanostructured polymer films. Similar to atomic force microscopy the surface topography is probed. In addition, buried structures from inside the film are detectable. As an example of the actual limits, nanostructures resulting from destabilized diblock copolymer films of poly(styrene-block-paramethylstyrene) in the highly confined regime are investigated. The stability of the structure, introduced by toluene vapor treatment, against annealing above the micro-phase separation temperature is shown.

  17. Grazing incidence small-angle neutron scattering - an advanced scattering technique for the investigation of nanostructured polymer films

    International Nuclear Information System (INIS)

    Mueller-Buschbaum, P.; Gutmann, J.S.; Cubitt, R.; Petry, W.

    2004-01-01

    With grazing incidence small-angle neutron scattering (GISANS), the limitations of conventional small-angle neutron scattering with respect to extremely small sample volumes in the thin-film geometry are overcome. GISANS turned out to be a powerful advanced scattering technique for the investigation of nanostructured polymer films. Similar to atomic force microscopy the surface topography is probed. In addition, buried structures from inside the film are detectable. As an example of the actual limits, nanostructures resulting from destabilized diblock copolymer films of poly(styrene-block-paramethylstyrene) in the highly confined regime are investigated. The stability of the structure, introduced by toluene vapor treatment, against annealing above the micro-phase separation temperature is shown

  18. Multiple small-angle neutron scattering for an arbitrary value of the Born parameter

    International Nuclear Information System (INIS)

    Bogdanov, S.G.; Men'shikov, A. Z.

    2000-01-01

    Computer calculations are made of the intensity of multiple small-angle neutron scattering using the general Moliere formula over a wide range of variation of the Born parameter, embracing the diffraction and refraction regimes, and a transition region between diffraction and reflection. A comparison is made with approximate formulas obtained earlier by Maleev et al. in the limiting cases of the Born parameter α > 1 for the diffraction and refraction regimes, respectively. It is shown that over a wide range of values of α the results of the calculations using the approximate and general formulas are the same. The theoretical conclusions were checked experimentally using data from measurements of small-angle neutron scattering for the domain structure of ferromagnets. Measurements were made of the neutron beam broadening for samples of different thickness and these were used to determine the effective domain sizes in pure iron and nickel exposed to thermal treatment and plastic deformation, and also in the Invar alloys Fe 65 Ni 35 and Fe 3 Pt. An analysis is made of the angular dependence of magnetic small-angle neutron scattering at the asymptote

  19. Design Principle of A Small Angle Neutron Scattering Spectrometer. Vol. 2

    International Nuclear Information System (INIS)

    Ashry, A.

    1996-01-01

    The design principle of a small angle neutron scattering (SANS) spectrometer is based on producing monochromatic neutron bursts using two phased rotors. The rotors have a number of slots to achieve the highly available intensity of monoenergetic neutrons at the required resolution. The design principle was applied to improve the performance of the pulsed monochromatic double rotor system at ET-RR-1 to operate as SANS spectrometer. It is shown that for rotors having 19 slots each with radius of curvature 96.8 cm, the intensity gain factor is 13. The proposed SANS spectrometer could cover the neutron wavelength range from 2 A ο up to 6 A ο through small angles of scattering from 5 x 10 -3 rad. to 0.1 rad. i.e, the scattering wavevector transfer between 0.6 A ο-1 and 0.01 A ο-1 . The maximum neutron flux density on the specimen is 5 x 10 5 n cm -2 s -1 . 8 figs

  20. Small angle x-ray and neutron scattering for materials characterisation

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, C.E. [Curtin University of Technology, Perth, WA (Australia). Department of Applied Physics

    1999-12-01

    Full text: Small angle X-ray and neutron scattering (SAXS and SANS) are excellent techniques to characterise inhomogeneities in materials in the size range from 10 Angstroms to several thousand Angstroms. Ultra small angle neutron and X-ray scattering (USANS and USAXS) have extended this size range out to 20 {mu}m. SAXS is due to the electron density difference between the matrix and the inhomogeneity, whereas SANS is due to the scattering length density difference. SANS and SAXS have been used successfully to characterise colloidal particles in solution, colloidal powders, glasses and a wide range of solids such as metals, alloys, and natural and synthetic high polymers. Small angle scattering and complementary techniques, such transmission and scanning electron microscopy (TEM and SEM) are a powerful combination for the investigation of submicron particles. This paper will introduce the reader to the small angle scattering techniques and will use the aluminium hydrogen (Al-H) system as an example to demonstrate the applicability of each method. Aluminium foils (99.99% purity) and single crystals (99.999% purity) were charged with hydrogen using a gas plasma method (voltage range of 1.0 - 1.2 keV). The results from the SANS, USANS, TEM, SEM, X-ray diffraction and inelastic neutron scattering experiments showed a wide range of H{sub 2} bubbles on the surface and in the bulk of the Al-H sample (< 10 Angstroms up to several microns in size). The volume of the H{sub 2} bubbles was formed by the diffusion of H-vacancy complexes into the bulk. The volume concentration of vacant sites determined from precision density measurements was within experimental error to that calculated from the SANS and USANS experiments. Copyright (1999) Australian X-ray Analytical Association Inc. 5 refs.

  1. Small angle x-ray and neutron scattering for materials characterisation

    International Nuclear Information System (INIS)

    Buckley, C.E.

    1999-01-01

    Full text: Small angle X-ray and neutron scattering (SAXS and SANS) are excellent techniques to characterise inhomogeneities in materials in the size range from 10 Angstroms to several thousand Angstroms. Ultra small angle neutron and X-ray scattering (USANS and USAXS) have extended this size range out to 20 μm. SAXS is due to the electron density difference between the matrix and the inhomogeneity, whereas SANS is due to the scattering length density difference. SANS and SAXS have been used successfully to characterise colloidal particles in solution, colloidal powders, glasses and a wide range of solids such as metals, alloys, and natural and synthetic high polymers. Small angle scattering and complementary techniques, such transmission and scanning electron microscopy (TEM and SEM) are a powerful combination for the investigation of submicron particles. This paper will introduce the reader to the small angle scattering techniques and will use the aluminium hydrogen (Al-H) system as an example to demonstrate the applicability of each method. Aluminium foils (99.99% purity) and single crystals (99.999% purity) were charged with hydrogen using a gas plasma method (voltage range of 1.0 - 1.2 keV). The results from the SANS, USANS, TEM, SEM, X-ray diffraction and inelastic neutron scattering experiments showed a wide range of H 2 bubbles on the surface and in the bulk of the Al-H sample ( 2 bubbles was formed by the diffusion of H-vacancy complexes into the bulk. The volume concentration of vacant sites determined from precision density measurements was within experimental error to that calculated from the SANS and USANS experiments. Copyright (1999) Australian X-ray Analytical Association Inc

  2. Small angle neutron scattering study of nanostructure in permanent magnet materials and coercivity mechanism

    International Nuclear Information System (INIS)

    Kato, Hiroaki

    2008-01-01

    Small angle neutron scattering study was performed in sintered Nd-Fe-B permanent magnets. The 99% enriched 11 B isotope was used to avoid high neutron absorption of 10 B in natural boron. In all the samples examined, the intensity of scattered neutrons was proportional to the q -4 for q -1 , irrespective of the direction of q. For q>0.5 nm -1 , on the other hand, the intensity was markedly higher than that expected from the q -4 dependence. These results show that there exists a neutron scatterer with a dimension of less than 10 nm, which is considered to be a Nd-rich grain boundary phase in the matrix of Nd 2 Fe 14 B phase. In the sample with Al and Cu additives, we observed a small but finite increase of intensity as compared with the sample without Al and Cu additives for the q range of 0.1 -1 . Since Al- and Cu-containing samples have higher coercivity, this result suggests that there is a correlation between the density of neutron scatterer at a Nd-rich grain boundary and the coercivity. (author)

  3. Invisible detergents for structure determination of membrane proteins by small-angle neutron scattering.

    Science.gov (United States)

    Midtgaard, Søren Roi; Darwish, Tamim A; Pedersen, Martin Cramer; Huda, Pie; Larsen, Andreas Haahr; Jensen, Grethe Vestergaard; Kynde, Søren Andreas Røssell; Skar-Gislinge, Nicholas; Nielsen, Agnieszka Janina Zygadlo; Olesen, Claus; Blaise, Mickael; Dorosz, Jerzy Józef; Thorsen, Thor Seneca; Venskutonytė, Raminta; Krintel, Christian; Møller, Jesper V; Frielinghaus, Henrich; Gilbert, Elliot Paul; Martel, Anne; Kastrup, Jette Sandholm; Jensen, Poul Erik; Nissen, Poul; Arleth, Lise

    2018-01-01

    A novel and generally applicable method for determining structures of membrane proteins in solution via small-angle neutron scattering (SANS) is presented. Common detergents for solubilizing membrane proteins were synthesized in isotope-substituted versions for utilizing the intrinsic neutron scattering length difference between hydrogen and deuterium. Individual hydrogen/deuterium levels of the detergent head and tail groups were achieved such that the formed micelles became effectively invisible in heavy water (D 2 O) when investigated by neutrons. This way, only the signal from the membrane protein remained in the SANS data. We demonstrate that the method is not only generally applicable on five very different membrane proteins but also reveals subtle structural details about the sarco/endoplasmatic reticulum Ca 2+ ATPase (SERCA). In all, the synthesis of isotope-substituted detergents makes solution structure determination of membrane proteins by SANS and subsequent data analysis available to nonspecialists. © 2017 Federation of European Biochemical Societies.

  4. Invisible detergents for structure determination of membrane proteins by small-angle neutron scattering

    DEFF Research Database (Denmark)

    Midtgaard, Søren Roi; Darwish, Tamim A.; Pedersen, Martin Cramer

    2018-01-01

    A novel and generally applicable method for determining structures of membrane proteins in solution via small-angle neutron scattering (SANS) is presented. Common detergents for solubilizing membrane proteins were synthesized in isotope-substituted versions for utilizing the intrinsic neutron...... scattering length difference between hydrogen and deuterium. Individual hydrogen/deuterium levels of the detergent head and tail groups were achieved such that the formed micelles became effectively invisible in heavy water (D2 O) when investigated by neutrons. This way, only the signal from the membrane...... protein remained in the SANS data. We demonstrate that the method is not only generally applicable on five very different membrane proteins but also reveals subtle structural details about the sarco/endoplasmatic reticulum Ca2+ ATPase (SERCA). In all, the synthesis of isotope-substituted detergents makes...

  5. Small-angle neutron scattering by water-based ferrofluid mixed with polyethylene glycol

    International Nuclear Information System (INIS)

    Feoktystov, A.V.; Avdeev, M.V.; Feoktystov, A.V.; Garamus, V.M.; Feoktystov, A.V.; Bulavin, L.A.; Kopcansky, P.; Timko, M.; Koneracka, M.; Zavisova, V.

    2009-01-01

    A new approach in the contrast variation experiments (small-angle neutron scattering) is demonstrated with a complex water-based magnetic fluid, where magnetite nanoparticles (size about 10 nm) coated with sodium oleate are mixed with poly(ethylene glycol), PEG. The contrast variations is performed basing on the substitution of hydrogen with deuterium in the liquid carrier (water). Modified basic functions defined for the polydisperse multicomponent superparamagnetic system are analyzed

  6. Small angle neutron scattering study of isolated single wall carbon nano tubes in water

    International Nuclear Information System (INIS)

    Doe, Chang-Woo; Kim, Tae-Hwan; Choi, Sung-Min; Kline, Steven R.

    2007-01-01

    As an effort to provide more practical approaches to a wide range of potential applications of carbon nano tubes, we report a new type of noncovalently functionalized isolated single-walled carbon nano tube(SWNT) which is easily dispersible in water by only ten minutes of mild vortex mixing. The structure and quality of dispersion have been investigated using small angle neutron scattering (SANS) technique

  7. Dispersion forces and small-angle neutron scattering from liquid noble metals

    International Nuclear Information System (INIS)

    March, N.H.

    1988-01-01

    Maggs and Ashcroft [Phys. Rev. letts., 59,113 (1987)] have re-opened the question of the analogy between the cohesion of a molecular crystal, in which dispersion forces play a major role, and that in a metal crystal with polarizable ion cores. It is pointed out that small-angle neutron scattering from liquid noble metals could be used to test their predictions. (author)

  8. Magnetic design of a spin-echo small-angle neutron-scattering instrument

    CERN Document Server

    Uca, O; Rekveldt, M T

    2003-01-01

    In a spin-echo small-angle neutron scattering instrument dipole magnets and guide field coils are used. The homogeneity of the fields should be sufficient to have linear labeling of the height with precession. Furthermore, the instrument must have a homogenous line integral over the beam cross-section. It is shown that line integral inhomogeneities are directly connected to field components perpendicular to the main field. The design parameters of these magnetic units of the setup are calculated.

  9. Reversible membrane reorganizations during photosynthesis in vivo: revealed by small-angle neutron scattering.

    Science.gov (United States)

    Nagy, Gergely; Posselt, Dorthe; Kovács, László; Holm, Jens K; Szabó, Milán; Ughy, Bettina; Rosta, László; Peters, Judith; Timmins, Peter; Garab, Gyozo

    2011-06-01

    In the present study, we determined characteristic repeat distances of the photosynthetic membranes in living cyanobacterial and eukaryotic algal cells, and in intact thylakoid membranes isolated from higher plants with time-resolved small-angle neutron scattering. This non-invasive technique reveals light-induced reversible reorganizations in the seconds-to-minutes time scale, which appear to be associated with functional changes in vivo.

  10. Study of humic acids by small-angle X-ray and neutron scattering

    International Nuclear Information System (INIS)

    Timchenko, A.; Trubetskaya, O.; Kihara, H.

    1999-01-01

    Humic acids are an important component of natural ecological system and represent a polydisperse complex of natural biopolymers with molecular masses from several to hundreds kilodaltons. They are both a source of organic compounds and a protector against anthropogenic pollutions of biosphere. The aim of the report is to underline some possibilities of small-angle X-ray and neutron scattering to study HA and their fractions. (author)

  11. Small-angle neutron scattering investigations of Co-doped iron oxide nanoparticles. Preliminary results

    Science.gov (United States)

    Creanga, Dorina; Balasoiu, Maria; Soloviov, Dmitro; Balasoiu-Gaina, Alexandra-Maria; Puscasu, Emil; Lupu, Nicoleta; Stan, Cristina

    2018-03-01

    Preliminary small-angle neutron scattering investigations on aqueous suspensions of several cobalt doped ferrites (CoxFe3-xO4, x=0; 0.5; 1) nanoparticles prepared by chemical co-precipitation method, are reported. The measurements were accomplished at the YuMO instrument in function at the IBR-2 reactor. Results of intermediary data treatment are presented and discussed.

  12. Depth-sensitive time-of-flight small-angle neutron scattering

    OpenAIRE

    Herbel, Jörg

    2013-01-01

    Block copolymers are quiet imported in industry. A detailed knowledge of the solid-liquid boundary conditions for surface effects in their aqueous solutions supports the development of smart coatings or the understanding of the folding of proteins in the vicinity of cell membranes. In this work, data collected from small-angle neutron scattering (SANS) experiments will be evaluated. The probed material is a 20\\% (in weight) solution of the polymer Pluronic F127, which forms micelles inside th...

  13. Two-dimensional position-sensitive detectors for small-angle neutron scattering

    International Nuclear Information System (INIS)

    McElhaney, S.A.; Vandermolen, R.I.

    1990-05-01

    In this paper, various detectors available for small angle neutron scattering (SANS) are discussed, along with some current developments being actively pursued. A section has been included to outline the various methodologies of position encoding/decoding with discussions on trends and limitations. Computer software/hardware vary greatly from institute and experiment and only a general discussion is given to this area. 85 refs., 33 figs

  14. Small-angle neutron scattering study of onion-type micelles

    Czech Academy of Sciences Publication Activity Database

    Pleštil, Josef; Kříž, Jaroslav; Tuzar, Zdeněk; Procházka, K.; Melnichenko, Yu. B.; Wignall, G. D.; Talingting, M. R.; Munk, P.; Webber, S. E.

    2001-01-01

    Roč. 202, č. 4 (2001), s. 553-563 ISSN 1022-1352 R&D Projects: GA ČR GA203/97/0249; GA ČR GA203/96/1387; GA MŠk VS97103; GA AV ČR KSK2050602 Institutional research plan: CEZ:AV0Z4050913 Keywords : onion -type micelles * small-angle neutron scattering Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.629, year: 2001

  15. Small angle neutron scattering investigations of spin disorder in nanocomposite soft magnets

    International Nuclear Information System (INIS)

    Vecchini, C.; Moze, O.; Suzuki, K.; Cadogan, J.M.; Pranzas, K.; Michels, A.; Weissmueller, J.

    2006-01-01

    The technique of SANS (small angle neutron scattering) furnishes unique information on the characteristic magnetic length scales and local magnetic anisotropies at the nanoscale in nanocomposite ferromagnets. Such information is not presently available using any other microscopic technique. The basic principles and results of the technique will be presented with regard to a unique and unexpected observation of a dipole field controlled spin disorder in a prototypical soft nanocomposite ferromagnet of the Nanoperm type

  16. Small angle neutron scattering study of ageing process in an Al-Mg-Si alloy

    International Nuclear Information System (INIS)

    Abis, S.; Fiorini, P.; Boeuf, A.; Caciuffo, R.; Crico, S.

    1984-01-01

    Small angle neutron scattering (SANS) measurements were performed on polycrystalline samples of high purity Al-Mg (0.72%)-Si (0.34%) alloy. The effect of different ageing temperature was observed and the results compared with information obtained using differen technique such as resistivity measurements and transmission electron microscopy. The results give useful information on the validity of SANS for the study of complex Al alloy

  17. Small angle neutron scattering form polymer melts: structural investigation and phase behaviour

    International Nuclear Information System (INIS)

    Ertugrul, O.

    2004-01-01

    The Small-Angle Neutron Scattering (SANS) techniques have been used to study the structural properties and phase behavior of polymer melts. A model based on Random Phase Approximation (RPA) is proposed to predict the experimental data. By fitting the model to data we could be able to obtain radius of gyration (a measure of size of a polymer) and phase transition for the sample. (author)

  18. Small Angle Neutron Scattering (SANS) Characterization of Electrically Conducting Polyaniline Nanofiber/Polyimide Nanocomposites

    Science.gov (United States)

    2011-10-25

    Electrically Conducting 5b. GRANT NUMBER Polyaniline Nanofiber/Polyimide Nanocomposites 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Alan R. Hopkins, Sandra J...Thin Solid Films 14. ABSTRACT Nanocomposites of polyaniline nanofibers and polyimide were fabricated and studied using small angle neutron...scattering (SANS). The immiscible nature of the conformationally dissimilar polyaniline nanofiber and polyimide host is established by a series of

  19. Small-angle neutron scattering from solutions of diblock copolymers in partially miscible solvents

    Czech Academy of Sciences Publication Activity Database

    Štěpánek, Petr; Tuzar, Zdeněk; Nallet, F.; Noirez, L.

    2005-01-01

    Roč. 38, č. 8 (2005), s. 3426-3431 ISSN 0024-9297 R&D Projects: GA ČR GA203/04/0490; GA ČR GA203/02/1262; GA ČR GESON/03/E001 Institutional research plan: CEZ:AV0Z4050913 Keywords : diblock copolymers * small angle neutron scattering * solvents Subject RIV: CD - Macromolecular Chemistry Impact factor: 4.024, year: 2005

  20. Experimental apparatus for the study of small angle neutron-proton elastic scattering at intermediate energies

    International Nuclear Information System (INIS)

    Vorobyov, A.A.; Korolev, G.A.; Dobrovolsky, A.V.; Khanzadeev, A.V.; Petrov, G.E.; Spiridenkov, E.M.; Terrien, Y.; Lugol, J.C.; Saudinos, J.; Silverman, B.H.; Wellers, F.

    1988-01-01

    An experimental setup for measurements of absolute differential cross sections and analyzing powers in small angle elastic np scattering is described. The main part of the apparatus consists of a multielectrode ionization chamber IKAR filled with methane, serving as both a gas target and a recoil detector. The apparatus was used in measurements with a polarized neutron beam from the Saturne synchrotron (Saclay, France) in the energy range from 378 to 1135 MeV. (orig.)

  1. On Small-Angle Neutron Scattering from Microemulsion Droplets the Role of Shape Fluctuations

    CERN Document Server

    Lisy, V

    2001-01-01

    The form factor and intensity of static neutron scattering from microemulsion droplets are calculated. The droplet is modeled by a double-layered sphere consisting of a fluid core and a thin surfactant layer, immersed in another fluid. All the three components are incompressible and characterized by different scattering length densities. As distinct from previous descriptions of small-angle neutron scattering (SANS), we consistently take into account thermal fluctuations of the droplet shape, to the second order of the fluctuations of the droplet radius. The properties of the layer are described within Helfrich's concept of the elasticity of curved interfaces. It is shown that in many cases the account for the fluctuations is essential for the interpretation of SANS. Information about two elastic constants \\kappa and \\bar\\kappa (so far extracted from the experiments in the combination 2\\kappa+\\bar\\kappa) can be now simultaneously obtained from SANS for system in conditions of two-phase coexistence. As an illu...

  2. Time-resolved small-angle neutron scattering of a micelle-to-vesicle transition

    Energy Technology Data Exchange (ETDEWEB)

    Egelhaaf, S.U. [Institut Max von Laue - Paul Langevin (ILL), 38 -Grenoble (France); Schurtenberger, P. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-04-01

    Amphiphilic molecules spontaneously self-assemble in solution to form a variety of aggregates. Only limited information is available on the kinetics of the structural transitions as well as on the existence of non-equilibrium or metastable states. Aqueous mixtures of lecithin and bile salt are very interesting biological model-systems which exhibit a spontaneous transition from polymer-like mixed micelles to vesicles upon dilution. The small-angle neutron scattering (SANS) instrument D22, with its very high neutron flux and the broad range of scattering vectors covered in a single instrumental setting, allowed us for the first time to perform time-resolved scattering experiments in order to study the micelle-to-vesicle transition. The temporal evolution of the aggregate structures were followed and detailed information was obtained even on molecular length-scales. (author). 5 refs.

  3. Small-Angle Neutron Scattering investigations of ferrofluids with different carrier liquids

    International Nuclear Information System (INIS)

    Balasoiu, M.; Avdeev, M. V.; Hasegan, D.; Ghenescu, V.; Ghenescu, M.; Bica, D.; Vekas, L.

    2004-01-01

    The aim of this paper is to present a method to investigate the properties of magnetic fluids by means of small angle neutron scattering (SANS). Ferrofluids are dispersions of small, single-domain magnetic particles suspended in a fluid carrier. The neutron scattering methods have been largely used the last two decades for the determination of structural properties of magnetic liquids at microscopic level. There can be investigated the structure of the particle, the aggregation phenomena, the magnetic liquid dynamics, particle-surfactant interaction, surfactant liquid-base interaction and structure and magnetic behavior of the samples. SANS is often used in structural studies of ferrofluids exploring two specific features of neutrons, the possibility of wide contrast variation using protonated/deuterated components and high magnetic scattering from ferromagnetics. This method can be effectively used for determination of the structural parameters of ferrofluids at the scale interval of 1-100 nm. In previous SANS experiments with ferrofluids of the same type it was shown that the nuclear scattering is described well by the spherical core-shell model (magnetite core plus surfactant shell) in a wide interval of momentum transfer (0.05 - 5 nm -1 ) and no significant effects of aggregation and interparticle interaction were observed in this interval for the magnetite concentration up to 5 vol. %. Experiments on small angle neutron scattering were carried out on SANS instrument YuMO in function at IBR-2 high pulsed reactor at the Frank Laboratory of Neutron Physics, Joint Institute of Nuclear Research, Dubna, Russia. (authors)

  4. Analysis of artificial silicon microstructures by ultra-small-angle and spin-echo small-angle neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Trinker, M. [Atominstitut, Vienna University of Technology, A-1020 Vienna (Austria)], E-mail: mtrinker@ati.ac.at; Jericha, E. [Atominstitut, Vienna University of Technology, A-1020 Vienna (Austria); Bouwman, W.G. [Faculty of Applied Sciences, Delft University of Technology, 2629 JB Delft (Netherlands); Loidl, R. [Atominstitut, Vienna University of Technology, A-1020 Vienna (Austria); Institute Laue-Langevin, F-38042 Grenoble (France); Rauch, H. [Atominstitut, Vienna University of Technology, A-1020 Vienna (Austria)

    2007-09-11

    Ultra-Small-Angle Neutron Scattering (USANS) is currently becoming an effective technique for the analysis of structures in the micrometer range. The new Spin-Echo SANS (SESANS) method measures a signal in real space. In both cases microfabricated silicon gratings provide unique test procedures for the related devices and interpretations of the experimental data. A series of one-dimensional gratings was fabricated using a highly anisotropic ion etching technique (RIE) and measured at the USANS instrument S18 at ILL, Grenoble. Grating parameters derived from the experimental data are in agreement with the nominal values. Scattering length density correlation functions calculated from the USANS data are compared to SESANS correlation functions measured at the Delft University of Technology, demonstrating the reciprocity of the two scattering methods. Reconstruction techniques for one-dimensional scattering length density distributions are applied to the USANS data. The results are in good agreement with SEM micrographs of the samples.

  5. Small-Angle neutron scattering at the Australian Replacement Research Reactor

    International Nuclear Information System (INIS)

    Gilbert, E.P.

    2002-01-01

    Full text: A small-angle neutron scattering (SANS) instrument is being designed as part of the initial instrument suite for the 20 MW Australian Replacement Research Reactor. The new instrument, receiving neutrons from a large liquid-D2 cold source, will be in the spirit of the world's best facilities and will greatly build upon ANSTO's existing expertise and facilities. Scheduled for completion in January 2006, it will provide Australian and international researchers with opportunities to access state-of-the-art SANS instrumentation. The conceptual details of the new SANS will be presented

  6. Magnetic and Crystalline Nanostructures in Ferrofluids as Probed by Small Angle Neutron Scattering

    Science.gov (United States)

    Wiedenmann, A.

    We present a newly developed technique of nuclear and magnetic contrast variation by using polarised neutrons in Small Angle Neutron Scattering (SANSPOL) which allows density, concentration and magnetisation fluctuations in magnetic liquids to be analysed simultaneously. Diluted Ferrofluids based on different magnetic materials (Co, Magnetite, Ba-ferrite) and stabilized by charges or surfactants in different carrier liquids have been investigated. In such polydisperse systems several constituents of similar sizes have been identified by this technique: Magnetic core-shell composites, magnetic aggregates and free surfactants. The corresponding size distributions, compositions and magnetic moments have been determined. In more concentrated Co-FF the nature of field induced particle arrangements has been determined.

  7. The very low angle detector for high-energy inelastic neutron scattering on the VESUVIO spectrometer

    International Nuclear Information System (INIS)

    Perelli Cippo, E.; Gorini, G.; Tardocchi, M.; Pietropaolo, A.; Andreani, C.; Senesi, R.; Rhodes, N.J.; Schooneveld, E.M.

    2008-01-01

    The Very Low Angle Detector (VLAD) bank has been installed on the VESUVIO spectrometer at the ISIS spallation neutron source. The new device allows for high-energy inelastic neutron scattering measurements, at energies above 1 eV, maintaining the wave vector transfer lower than 10A -1 . This opens a still unexplored region of the kinematical (q,ω) space, enabling new and challenging experimental investigations in condensed matter. This paper describes the main instrumental features of the VLAD device, including instrument design, detector response, and calibration procedure

  8. The very low angle detector for high-energy inelastic neutron scattering on the VESUVIO spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Perelli Cippo, E.; Gorini, G.; Tardocchi, M. [Dipartimento di Fisica ' G. Occhialini' , Universita degli Studi di Milano-Bicocca, Piazza della Scienza 3, 20126 Milano (Italy); Pietropaolo, A. [Dipartimento di Fisica ' G. Occhialini' , CNISM-Universita degli Studi di Milano-Bicocca, Piazza della Scienza 3, 20126 Milano (Italy); NAST Center - Nanoscienze-Nanotecnologie-Strumentazione, Universita degli Studi di Roma Tor Vergata, via della Ricerca Scientifica 1, 00133 Roma (Italy)], E-mail: antonino.pietropaolo@mib.infn.it; Andreani, C.; Senesi, R. [Dipartimento di Fisica and Centro NAST - Nanoscienze-Nanotecnologie-Strumentazione, Universita degli Studi di Roma Tor Vergata, via della Ricerca Scientifica 1, 00133 Roma (Italy); Rhodes, N.J.; Schooneveld, E.M. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire 0QX OX11 (United Kingdom)

    2008-05-01

    The Very Low Angle Detector (VLAD) bank has been installed on the VESUVIO spectrometer at the ISIS spallation neutron source. The new device allows for high-energy inelastic neutron scattering measurements, at energies above 1 eV, maintaining the wave vector transfer lower than 10A{sup -1}. This opens a still unexplored region of the kinematical (q,{omega}) space, enabling new and challenging experimental investigations in condensed matter. This paper describes the main instrumental features of the VLAD device, including instrument design, detector response, and calibration procedure.

  9. Structure investigations on Portland cement paste by small angle neutron scattering

    International Nuclear Information System (INIS)

    Dragolici, C.A.; Lin, A.

    2004-01-01

    Hydrated Portland cement is a very complex material. Cement paste consists of many crystalline and non-crystalline phases in various ranges of sizes (μm and nm scale). The crystalline phases are embedded in amorphous phases of hydration products. We investigated the structural changes of hydrating phases in a time interval up to 18 days, at Budapest Neutron Center's SANS spectrometer. The small angle neutron scattering of Portland cements prepared with a various water-to-cement ratios, gave us information about the microstructure changes in the material. Fractals were a suitable way for structure modelling. Some comments regarding the opportunity of using the most common models are pointed out. (authors)

  10. Thirty meters small angle neutron scattering instrument at China advanced research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongxia [State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Cheng, He, E-mail: hecheng@iccas.ac.cn [State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Yuan, Guangcui [State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Han, Charles C., E-mail: c.c.han@iccas.ac.cn [State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Zhang, Li; Li, Tianfu; Wang, Hongli; Liu, Yun Tao; Chen, Dongfeng [China Institute of Atomic Energy, PO Box-275-30, Beijing 102413 (China)

    2014-01-21

    A high resolution 30 m small angle neutron scattering (SANS) instrument has been constructed by the Institute of Chemistry, Chinese Academy of Sciences (ICCAS), and installed at China Advanced Research Reactor (CARR). It is equipped with a mechanical velocity selector, pinhole (including multi-pinhole) collimation system, sample chamber, and high resolution two dimensional {sup 3}He position sensitive neutron detector. The flexible variations of incident neutron wavelength, source to sample distance, sample to detector distance and the presence of neutron focusing lenses enable a wide Q range from 0.001 Å{sup −1} to 0.5 Å{sup −1} in reciprocal space and to optimize the resolution required. The instrument is the first SANS instrument in China, and can be widely used for the structure characterization of various materials, as well as kinetic and dynamic observation during external stimulation. The design and characteristics of the instrument are presented in the manuscript. -- Highlights: • The first small angle neutron scattering instrument in China is developed. • It is equipped with a pinhole, multi-pinhole and focusing lenses. • It provides flexible variations of source-sample and sample-detector distances. • A wide Q ranges from 0.001 Å{sup −1} to 0.5 Å{sup −1} in reciprocal space.

  11. Grazing-incidence small-angle neutron scattering from structures below an interface.

    Science.gov (United States)

    Nouhi, Shirin; Hellsing, Maja S; Kapaklis, Vassilios; Rennie, Adrian R

    2017-08-01

    Changes of scattering are observed as the grazing angle of incidence of an incoming beam increases and probes different depths in samples. A model has been developed to describe the observed intensity in grazing-incidence small-angle neutron scattering (GISANS) experiments. This includes the significant effects of instrument resolution, the sample transmission, which depends on both absorption and scattering, and the sample structure. The calculations are tested with self-organized structures of two colloidal samples with different size particles that were measured on two different instruments. The model allows calculations for various instruments with defined resolution and can be used to design future improved experiments. The possibilities and limits of GISANS for different studies are discussed using the model calculations.

  12. Characterization of porous materials using combined small-angle X-ray and neutron scattering techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Naiping; Borkar, Neha; Kohls, Doug; Schaefer, Dale W. (UCIN)

    2014-09-24

    A combination of ultra small angle X-ray scattering (USAXS) and ultra small angle neutron scattering (USANS) is used to characterize porous materials. The analysis methods yield quantitative information, including the mean skeletal chord length, mean pore chord length, skeletal density, and composition. A mixed cellulose ester (MCE) membrane with a manufacturer-labeled pore size of 0.1 {mu}m was used as a model to elucidate the specifics of the method. Four approaches describing four specific scenarios (different known parameters and form of the scattering data) are compared. Pore chords determined using all four approaches are in good agreement with the scanning electron microscopy estimates but are larger than the manufacturer's nominal pore size. Our approach also gives the average chord of the skeletal solid (struts) of the membrane, which is also consistent for all four approaches. Combined data from USAXS and USANS gives the skeletal density and the strut composition.

  13. Characterization of porous materials using combined small-angle X-ray and neutron scattering techniques

    International Nuclear Information System (INIS)

    Hu, Naiping; Borkar, Neha; Kohls, Doug; Schaefer, Dale W.

    2012-01-01

    A combination of ultra small angle X-ray scattering (USAXS) and ultra small angle neutron scattering (USANS) is used to characterize porous materials. The analysis methods yield quantitative information, including the mean skeletal chord length, mean pore chord length, skeletal density, and composition. A mixed cellulose ester (MCE) membrane with a manufacturer-labeled pore size of 0.1 μm was used as a model to elucidate the specifics of the method. Four approaches describing four specific scenarios (different known parameters and form of the scattering data) are compared. Pore chords determined using all four approaches are in good agreement with the scanning electron microscopy estimates but are larger than the manufacturer's nominal pore size. Our approach also gives the average chord of the skeletal solid (struts) of the membrane, which is also consistent for all four approaches. Combined data from USAXS and USANS gives the skeletal density and the strut composition.

  14. Structure of fullerene aggregates in pyridine/water solutions by small-angle neutron scattering

    International Nuclear Information System (INIS)

    Aksenov, V.L.; Belushkin, A.V.; Avdeev, M.V.; Rosta, L.; Mihailovic, D.; Mrzel, A.; Serdyuk, I.N.; Timchenko, A.A.

    2001-01-01

    Results of small-angle neutron scattering experiments on fullerenes (C 60 ) in pyridine/water solutions are reported. They confirm conclusions of the previous studies, in particular, dynamic light scattering experiments. Aggregates with characteristic radius of about 20 nm are formed in the solutions. The contrast variation using different combinations of protonated/deuterated components (water and pyridine) of the solutions points to the small pyridine content inside the aggregates. This fact testifies that the aggregates consist of a massive fullerene core covered by a thin pyridine shell

  15. Small angle neutron scattering at very high time resolution: Principle and simulations of 'TISANE'

    International Nuclear Information System (INIS)

    Kipping, D.; Gaehler, R.; Habicht, K.

    2008-01-01

    The time resolution of SANS experiments is generally limited by frame overlap to some ms. We report on a new time-resolved stroboscopic SANS method, called TISANE, offering μs time resolution without a major sacrifice in intensity by making use of very large frame overlap. We may explore a new field in neutron scattering and complement the emerging field of time resolved small angle X-ray scattering. Here we discuss the principle of TISANE, its mathematical treatment and its limitations

  16. Small-angle neutron scattering from multilamellar lipid bilayers: Theory, model, and experiment

    DEFF Research Database (Denmark)

    Lemmich, Jesper; Mortensen, Kell; Ipsen, John Hjorth

    1996-01-01

    Small-angle neutron scattering data obtained from fully hydrated, multilamellar phospholipid bilayers with deuterated acyl chains of different length are presented and analyzed within a paracrystalline theory and a geometric model that permit the bilayer structure to be determined under conditions...... where the lamellar layers are coupled and fluctuating. This theory provides structural information in the region of the solid-fluid bilayer phase transition without invoking the usual decoupling of the scattering intensity function into form and structure factors. Results are presented as a function...

  17. Precise study of vortex structures in Nb by small-angle neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Miyata, Seiki; Osamura, Kozo [Department of Materials Science and Engineering, Kyoto Univ., Kyoto (Japan); Suzuki, Jun-ichi [Advanced Science Reserch Center, Japan Atomic Energy Research Institute, Tokai, Ibaraki (Japan)

    2001-07-01

    The microscopic magnetic structure of a vortex in a Nb single crystal was investigated using small-angle neutron scattering by measuring higher order reflections. By fitting the experimental scattering intensities, the magnetic structure of a vortex can be represented by the London equation with an additional Gaussian factor due to the thermal displacement of vortices. The radius of a vortex (20.3 nm at 3.3 K) is somewhat smaller than the London penetration depth ({lambda}{sub L}(0) = 31.5-39.0 nm). (author)

  18. Wide-angle polarization analysis with 3He for neutron scattering instrumentation at the JCNS

    Science.gov (United States)

    Ioffe, A.; Babcock, E.; Pipich, V.; Radulescu, A.

    2011-06-01

    Polarization analysis is an important technique for polarized neutron scattering as it allows one to obtain the full information about the vector magnetization in the sample that is critically important for detailed understanding of physical properties of molecular magnets, new superconductors, spin electronic and magnetic nanostructures, as well as the self-organization of magnetic nanostructures. In the simplified 1-dimensional version polarization analysis allows for the separation of coherent and incoherent scattering, making it a potentially important technique for studies of non-deuterated biological objects that themselves produce unavoidable background. We compare some of the major considerations between two different methods for the polarization analysis - supermirror based analyzers and polarized 3He neutron spin filters and point out when the latter is beneficial from the point of view of our neutron experiments and instrumentation. We will also discuss some specific requirements to such neutron spin filters and summarize the classes of instrumentation where they will be applied at the JCNS. Finally we will describe a successful application for small-angle neutron scattering from a biological sample.

  19. Wide-angle polarization analysis with 3He for neutron scattering instrumentation at the JCNS

    International Nuclear Information System (INIS)

    Ioffe, A; Babcock, E; Pipich, V; Radulescu, A

    2011-01-01

    Polarization analysis is an important technique for polarized neutron scattering as it allows one to obtain the full information about the vector magnetization in the sample that is critically important for detailed understanding of physical properties of molecular magnets, new superconductors, spin electronic and magnetic nanostructures, as well as the self-organization of magnetic nanostructures. In the simplified 1-dimensional version polarization analysis allows for the separation of coherent and incoherent scattering, making it a potentially important technique for studies of non-deuterated biological objects that themselves produce unavoidable background. We compare some of the major considerations between two different methods for the polarization analysis - supermirror based analyzers and polarized 3 He neutron spin filters and point out when the latter is beneficial from the point of view of our neutron experiments and instrumentation. We will also discuss some specific requirements to such neutron spin filters and summarize the classes of instrumentation where they will be applied at the JCNS. Finally we will describe a successful application for small-angle neutron scattering from a biological sample.

  20. Outline of Neutron Scattering Formalism

    OpenAIRE

    Berk, N. F.

    1993-01-01

    Neutron scattering formalism is briefly surveyed. Topics touched upon include coherent and incoherent scattering, bound and free cross-sections, the Van Hove formalism, magnetic scattering, elastic scattering, the static approximation, sum rules, small angle scattering, inelastic scattering, thermal diffuse scattering, quasielastic scattering, and neutron optics.

  1. Neutron small-angle scattering by dislocations in homogeneously oriented nematic liquid crystals

    International Nuclear Information System (INIS)

    Olivei, A.

    1976-01-01

    A complete examination of the shape of the neutron-scattering cross-section curves at very small scattering vectors, of the order of 0.05 to approximately 0.1 nm -1 , has been made for homogeneously oriented nematic liquid crystals. It is shown that the shape of the scattering curves at small angles is mainly determined by the kind of dislocation configuration exhibited by homogeneously oriented nematic liquid crystals. This study will furnish a partial guide to the construction of scattering relations for any kind of possible dislocation configuration in homogeneously oriented nematic liquid crystals, e.g. for stationary straight edge dislocations, moving edge dislocations, oscillating edge dislocations, curved dislocations and dislocation networks. (Auth.)

  2. Light-Induced Structural Flexibility of Thylakoid Membranes - Investigated using Small-Angle X-ray and Neutron Scattering

    OpenAIRE

    Aagaard, Thomas Helverskov

    2005-01-01

    Using small-angle x-ray and neutron scattering the light-induced structural changes in pea thylakoids have been investigated. It is shown that light-induced shinkage in the thylakoids is connected to photosynthetic electron transduction. Using small-angle x-ray and neutron scattering the light-induced structural changes in pea thylakoids have been investigated. It is shown that light-induced shinkage in the thylakoids is connected to photosynthetic electron transduction.

  3. Wavelength-independent constant period spin-echo modulated small angle neutron scattering.

    Science.gov (United States)

    Sales, Morten; Plomp, Jeroen; Habicht, Klaus; Tremsin, Anton; Bouwman, Wim; Strobl, Markus

    2016-06-01

    Spin-Echo Modulated Small Angle Neutron Scattering (SEMSANS) in Time-of-Flight (ToF) mode has been shown to be a promising technique for measuring (very) small angle neutron scattering (SANS) signals and performing quantitative Dark-Field Imaging (DFI), i.e., SANS with 2D spatial resolution. However, the wavelength dependence of the modulation period in the ToF spin-echo mode has so far limited the useful modulation periods to those resolvable with the limited spatial resolution of the detectors available. Here we present our results of an approach to keep the period of the induced modulation constant for the wavelengths utilised in ToF. This is achieved by ramping the magnetic fields in the coils responsible for creating the spatially modulated beam in synchronisation with the neutron pulse, thus keeping the modulation period constant for all wavelengths. Such a setup enables the decoupling of the spatial detector resolution from the resolution of the modulation period by the use of slits or gratings in analogy to the approach in grating-based neutron DFI.

  4. Magnetic scattering in the simultaneous measurement of small-angle neutron scattering and Bragg edge transmission from steel.

    Science.gov (United States)

    Oba, Yojiro; Morooka, Satoshi; Ohishi, Kazuki; Sato, Nobuhiro; Inoue, Rintaro; Adachi, Nozomu; Suzuki, Jun-Ichi; Tsuchiyama, Toshihiro; Gilbert, Elliot Paul; Sugiyama, Masaaki

    2016-10-01

    Pulsed neutron sources enable the simultaneous measurement of small-angle neutron scattering (SANS) and Bragg edge transmission. This simultaneous measurement is useful for microstructural characterization in steel. Since most steels are ferromagnetic, magnetic scattering contributions should be considered in both SANS and Bragg edge transmission analyses. An expression for the magnetic scattering contribution to Bragg edge transmission analysis has been derived. The analysis using this expression was applied to Cu steel. The ferrite crystallite size estimated from this Bragg edge transmission analysis with the magnetic scattering contribution was larger than that estimated using conventional expressions. This result indicates that magnetic scattering has to be taken into account for quantitative Bragg edge transmission analysis. In the SANS analysis, the ratio of magnetic to nuclear scattering contributions revealed that the precipitates consist of body-centered cubic Cu 0.7 Fe 0.3 and pure Cu, which probably has 9R structure including elastic strain and vacancies. These results show that effective use of the magnetic scattering contribution allows detailed analyses of steel microstructure.

  5. Cold Neutron Focusing Multiple Biconcave Lenses and Anti-Gravity Prisms for 40m Small Angle Neutron Scattering Instrument

    International Nuclear Information System (INIS)

    Sim, Jun-Bo; Choi, Sung-Min

    2007-01-01

    Small angle neutron scattering (SANS) instrument with long flight path is a very powerful tool to investigate the structures of various nanoscale materials. Currently, a new 40m SANS instrument is under development to be installed at HANARO, which will be one of the key facilities for nano-characterization in Korea. To enhance the measurement capability of the 40m SANS, especially in the low Q region, cold neutron focusing and cancellation of gravity effects using multiple biconcave lenses and prisms are suggested. In this paper, we present recent Monte Carlo simulation studies on the refractive focusing and anti-gravity optics

  6. Kookaburra - the ultra-small-angle neutron scattering instrument at OPAL

    International Nuclear Information System (INIS)

    Rehm, Christine

    2009-01-01

    Full text: An ultra-small-angle neutron scattering (USANS) instrument is to be built at ANSTO's new research reactor OPAL. This instrument will extend the range of experimentally measurable length scales currently accessible through the already existing SANS instrument Quokka by two orders of magnitude into the micrometre regime. Therefore, the combined USANS/SANS utilisation at ANSTO will allow the characterisation of microstructure over 4 orders of magnitude in size (1 nm to 10μm). Kookaburra is to be installed at the cold-neutron guide CG 3 , and will use the classical Bonse-Hart method. The instrument shall individually operate at two different wavelengths to optimally accommodate weakly and strongly scattering samples at one sample position. This contribution will discuss the layout and conceptual design of Kookaburra, and its expected performance is compared to that of the reactor-based USANS instrument BT-5 at NIST.

  7. Measuring material microstructure under flow using 1-2 plane flow-small angle neutron scattering.

    Science.gov (United States)

    Gurnon, A Kate; Godfrin, P Douglas; Wagner, Norman J; Eberle, Aaron P R; Butler, Paul; Porcar, Lionel

    2014-02-06

    A new small-angle neutron scattering (SANS) sample environment optimized for studying the microstructure of complex fluids under simple shear flow is presented. The SANS shear cell consists of a concentric cylinder Couette geometry that is sealed and rotating about a horizontal axis so that the vorticity direction of the flow field is aligned with the neutron beam enabling scattering from the 1-2 plane of shear (velocity-velocity gradient, respectively). This approach is an advance over previous shear cell sample environments as there is a strong coupling between the bulk rheology and microstructural features in the 1-2 plane of shear. Flow-instabilities, such as shear banding, can also be studied by spatially resolved measurements. This is accomplished in this sample environment by using a narrow aperture for the neutron beam and scanning along the velocity gradient direction. Time resolved experiments, such as flow start-ups and large amplitude oscillatory shear flow are also possible by synchronization of the shear motion and time-resolved detection of scattered neutrons. Representative results using the methods outlined here demonstrate the useful nature of spatial resolution for measuring the microstructure of a wormlike micelle solution that exhibits shear banding, a phenomenon that can only be investigated by resolving the structure along the velocity gradient direction. Finally, potential improvements to the current design are discussed along with suggestions for supplementary experiments as motivation for future experiments on a broad range of complex fluids in a variety of shear motions.

  8. Bilayer thickness in unilamellar phosphatidylcholine vesicles: small-angle neutron scattering using contrast variation

    International Nuclear Information System (INIS)

    Kucerka, N.; Uhrikova, D.; Teixeira, J.; Balgavy, P.

    2004-01-01

    The thickness of the lipid bilayer in extruded unilamellar vesicles prepared from synthetic 1,2-diacyl-sn-glycero-3-phosphorylcholines with monounsaturated acyl chains (diCn:1PC, n=14-22) was studied at 30 deg. C in the small-angle neutron scattering (SANS) experiment. Several contrasts of the neutron scattering length density between the aqueous phase and phospholipid bilayer of vesicles were used. The experimental data were evaluated using the small-angle form of the Kratky-Porod approximation ln[I(q)q 2 ] vs. q 2 of the SANS intensity I(q) in the appropriate range of scattering vector values q to obtain the bilayer radius of gyration R g and its extrapolated value at infinite scattering contrast R g inf . The bilayer thickness parameter evaluated from a linear approximation of dependence of gyration radius on the inverse contrast was then obtained without using any bilayer structure model. The dependence of the thickness parameter d g congruent with 12 0.5 R g inf on the number n of acyl chain carbons was found to be linear with a slope of 1.8±0.2 A per one acyl chain carbon. This slope can be used in bilayer-protein interaction studies

  9. REVIEWS OF TOPICAL PROBLEMS Small-angle neutron scattering in structure research of magnetic fluids

    Science.gov (United States)

    Avdeev, Mikhail V.; Aksenov, Viktor L.

    2011-01-01

    A magnetic fluid (MF) is a liquid dispersion of magnetic nanoparticles coated by surfactants for stabilization. The MF research reviewed in this paper is primarily aimed at investigating the atomic and magnetic structure of MF particles and the way they interact under various conditions by means of small-angle neutron scattering (SANS). The presence of a liquid carrier in the structure and the magnetic properties of MFs, which are very close to those of an ideal superparamagnetic system, allow the effective use of the major neutron scattering features: the strong effect of hydrogen-deuterium isotopic substitution and magnetic scattering. An extension of the contrast variation technique to the structure research on polydisperse and superparamagnetic systems is proposed. The cases of noninteracting and interacting particles, the latter with cluster formation taken into account, are considered for non-magnetized and magnetized MFs. The polarized neutron scattering analysis of the structure of magnetized MFs is illustrated by examples. Topical problems in further developing the method to study multiparameter systems are identified.

  10. Small-angle neutron scattering in structure research of magnetic fluids

    International Nuclear Information System (INIS)

    Avdeev, Mikhail V; Aksenov, Viktor L

    2011-01-01

    A magnetic fluid (MF) is a liquid dispersion of magnetic nanoparticles coated by surfactants for stabilization. The MF research reviewed in this paper is primarily aimed at investigating the atomic and magnetic structure of MF particles and the way they interact under various conditions by means of small-angle neutron scattering (SANS). The presence of a liquid carrier in the structure and the magnetic properties of MFs, which are very close to those of an ideal superparamagnetic system, allow the effective use of the major neutron scattering features: the strong effect of hydrogen-deuterium isotopic substitution and magnetic scattering. An extension of the contrast variation technique to the structure research on polydisperse and superparamagnetic systems is proposed. The cases of noninteracting and interacting particles, the latter with cluster formation taken into account, are considered for non-magnetized and magnetized MFs. The polarized neutron scattering analysis of the structure of magnetized MFs is illustrated by examples. Topical problems in further developing the method to study multiparameter systems are identified. (reviews of topical problems)

  11. Small angle neutron scattering and Moessbauer effect in nitrogen-bearing austenite

    International Nuclear Information System (INIS)

    Nadutov, V.M.; Garamus, V.M.; Islamov, A.Kh.

    2002-01-01

    The phase composition and changes in the close atomic order under the effect of the low-temperature annealing of the Fe-Cr-Mn-N steel are studied with application of the neutron diffraction and the Moessbauer spectroscopy method. The small angle neutron scattering (SANS) in the high-nitrogen Fe-19% Cr-19% Mn-0.9 N and Fe-18% Cr-10% Mn-16% Ni-0.5% N austenite is studied. The measurements and analysis of the neutron diffraction and the Moessbauer spectra are carried out. The character of the SANS in the nitrogen-bearing austenite is related to the existence of the micrononuniformities, the structure whereof depends on the nickel alloying. The average size and form of the nonuniformities are evaluated [ru

  12. The small angle neutron scattering spectrometer at the Budapest research reactor

    International Nuclear Information System (INIS)

    Retfalvi, E.; Almasy, L.; Toeroek, Gy.; Len, A.; Rosta, L.

    2001-01-01

    The reinstallation of the Small Angle Neutron Scattering spectrometer (named 'Yellow Submarine') at the Budapest Research Reactor has been finished in winter 2001. Parallel to the installation of a liquid hydrogen cold source, the guide system of the spectrometer was also rebuilt to a more optimized geometry. The old natural Ni-coated guide sections of 2.5x10 cm 2 after the velocity selector have been replaced by a new supermirror coated curved neutron guide with 4x4 cm 2 cross section. The neutron flux of the upgraded spectrometer is much higher. The beam is formed by a fixed length collimator tube and monitored by a fission chamber. (R.P.)

  13. A new small-angle neutron scattering spectrometer at China Mianyang research reactor

    Science.gov (United States)

    Peng, Mei; Sun, Liangwei; Chen, Liang; Sun, Guangai; Chen, Bo; Xie, Chaomei; Xia, Qingzhong; Yan, Guanyun; Tian, Qiang; Huang, Chaoqiang; Pang, Beibei; Zhang, Ying; Wang, Yun; Liu, Yaoguang; Kang, Wu; Gong, Jian

    2016-02-01

    A new pinhole small-angle neutron scattering (SANS) spectrometer, installed at the cold neutron source of the 20 MW China Mianyang Research Reactor (CMRR) in the Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, has been put into use since 2014. The spectrometer is equipped with a multi-blade mechanical velocity selector, a multi-beam collimation system, and a two-dimensional He-3 position sensitive neutron detector. The q-range of the spectrometer covers from 0.01 nm-1 to 5.0 nm-1. In this paper, the design and characteristics of the SANS spectrometer are described. The q-resolution calculations, together with calibration measurements of silver behenate and a dispersion of nearly monodisperse poly-methyl-methacrylate nanoparticles indicate that our SANS spectrometer has a good performance and is now in routine service.

  14. Small-angle neutron scattering investigation of the nanostructure of ferritic-martensitic 12%-chromium steels

    Science.gov (United States)

    Bogdanov, S. G.; Goshchitskii, B. N.; Parkhomenko, V. D.; Leontieva-Smirnova, M. V.; Chernov, V. M.

    2014-01-01

    The nanostructure (nanoparticle distribution) of ferritic-martensitic 12%-chromium steels EK-181 (Fe-12Cr-2W-V-Ta-B) and ChS-139 (Fe-12Cr-2W-V-Ta-B-Nb-Mo) subjected to different modes of mechanical and heat treatments and neutron irradiation has been investigated using small-angle neutron scattering. The samples have been studied in the initial state and after neutron irradiation (IVV-2M reactor) at a temperature of 80°C with fluences of 1018, 1019, and 5 × 1019 cm-2 ( E ≥ 0.1 MeV). The nanostructure of the steels is characterized by precipitations of nanoparticles with two characteristic sizes of 1.0-1.5 and 7-8 nm. The dependence of the nanostructure parameters on the composition of the steels and on the conditions of heat treatment and irradiation has been discussed.

  15. Small-angle neutron scattering investigations of nanocrystalline alloy chips obtained by machining

    Directory of Open Access Journals (Sweden)

    Elwyn Rebello

    2014-12-01

    Full Text Available Ultrafine-grained (UFG materials exhibit significantly enhanced mechanical properties. This has brought renewed attention on the use of large strain or severe plastic deformation as a means for achieving microstructural refinement in metals and alloys. Large plastic strains imposed in a machine chip result in significant microstructural refinement, including the creation of UFG and nanocrystalline materials. It looks to be an economical route for realizing nanocrystalline materials. In the present study, small-angle neutron scattering (SANS was employed to investigate the modifications in the microstructure of the chips produced via machining. Double crystal-based medium resolution SANS instrument has been used for this purpose. Significant scattering intensity at small enough angles reveals the presence of mesoscopic density fluctuations produced because of the machining. Atomic force microscopy images also corroborate the existence of such small length scale density fluctuations.

  16. Domain interaction in rabbit muscle pyruvate kinase. II. Small angle neutron scattering and computer simulation.

    Science.gov (United States)

    Consler, T G; Uberbacher, E C; Bunick, G J; Liebman, M N; Lee, J C

    1988-02-25

    The effects of ligands on the structure of rabbit muscle pyruvate kinase were studied by small angle neutron scattering. The radius of gyration, RG, decreases by about 1 A in the presence of the substrate phosphoenolpyruvate, but increases by about the same magnitude in the presence of the allosteric inhibitor phenylalanine. With increasing pH or in the absence of Mg2+ and K+, the RG of pyruvate kinase increases. Hence, there is a 2-A difference in RG between two alternative conformations. Length distribution analysis indicates that, under all experimental conditions which increase the radius of gyration, there is a pronounced increase observed in the probability for interatomic distance between 80 and 110 A. These small angle neutron scattering results indicate a "contraction" and "expansion" of the enzyme when it transforms between its active and inactive forms. Using the alpha-carbon coordinates of crystalline cat muscle pyruvate kinase, a length distribution profile was calculated, and it matches the scattering profile of the inactive form. These observations are expected since the crystals were grown in the absence of divalent cations (Stuart, D. I., Levine, M., Muirhead, H., and Stammers, D. K. (1979) J. Mol. Biol. 134, 109-142). Hence, results from neutron scattering, x-ray crystallographic, and sedimentation studies (Oberfelder, R. W., Lee, L. L.-Y., and Lee, J.C. (1984) Biochemistry 23, 3813-3821) are totally consistent with each other. With the aid of computer modeling, the crystal structure has been manipulated in order to effect changes that are consistent with the conformational change described by the solution scattering data. The structural manipulation involves the rotation of the B domain relative to the A domain, leading to the closure of the cleft between these domains. These manipulations resulted in the generation of new sets of atomic (C-alpha) coordinates, which were utilized in calculations, the result of which compared favorably with the

  17. Small-Angle Neutron Scattering study of the NIST mAb reference material

    Science.gov (United States)

    Castellanos, Maria Monica; Liu, Yun; Krueger, Susan; Curtis, Joseph

    Monoclonal antibodies (mAbs) are of great interest to the biopharmaceutical industry because they can be engineered to target specific antigens. Due to their importance, the biomanufacturing initiative at NIST is developing an IgG1 mAb reference material `NIST mAb', which can be used by industry, academia, and regulatory authorities. As part of this collaborative effort, we aim at characterizing the reference material using neutron scattering techniques. We have studied the small-angle scattering profile of the NIST mAb in a histidine buffer at 0 and 150 mM NaCl. Using Monte Carlo simulations, we generate an ensemble of structures and calculate their theoretical scattering profile, which can be directly compared with experimental data. Moreover, we analyze the structure factor to understand the effect of solution conditions on the protein-protein interactions. Finally, we have measured the solution scattering of the NIST mAb, while simultaneously performing freeze/thaw cycles, in order to investigate if the solution structure was affected upon freezing. The results from neutron scattering not only support the development of the reference material, but also provide insights on its stability and guide efforts for its development under different formulations.

  18. Methods of contrast variation by nuclear polarisation in small-angle neutron scattering: Observation of domains of nuclear polarisation by neutron scattering

    International Nuclear Information System (INIS)

    Leymarie, E.

    2002-11-01

    In this thesis we study the theoretical and experimental aspects of Contrast Variation by Nuclear Polarization (CVNP) applied to small-angle neutron scattering. The basics of neutron scattering theory is developed by highlighting the origin of the CVNP method: the strong spin dependence of thermal neutron scattering, especially on protons. We also present the principles of NMR with a special attention on the method of dynamic nuclear polarization by the solid effect which makes it possible to control the proton polarization and therefore the contrast for neutron scattering. We present a theoretical study of the CVNP method called static which supposes that the nuclear polarization is homogeneous in the sample and constant during the experiment. We show that it allows one to obtain partial structure functions of systems with multiple components, by carrying out several acquisitions with different polarizations on a single sample. For this purpose, we tested a simple device to stabilize the nuclear polarization. We describe finally a new application of the CVNP method called dynamic. In a solution of deuterated glycerol-water containing a small concentration of paramagnetic centres, we showed the existence of domains of polarized protons at the onset of dynamic polarization. This reinforces considerably the coherent scattering of paramagnetic centres. We describe the theoretical reasons explaining the appearance of these domains of polarization, as well as the various techniques used to observe them by neutron scattering. (author)

  19. Time of flight grazing incidence small angle neutron scattering. A novel scattering technique for the investigation of nanostructured polymer films

    Science.gov (United States)

    Müller-Buschbaum, P.; Metwalli, E.; Moulin, J.-F.; Kudryashov, V.; Haese-Seiller, M.; Kampmann, R.

    2009-02-01

    Grazing incidence small angle neutron scattering (GISANS) overcomes the limitations of conventional small angle scattering with respect to extremely small sample volumes in the thin film geometry. In time of flight (TOF) mode neutrons with a broad range of wavelengths are used simultaneously and recorded as a function of their respective times of flight. The combination of both, TOF-GISANS, enables the simultaneous performance of several GISANS measurements, which differ in wavelength. As a consequence, within one measurement a full set of GISANS pattern related to different scattering vectors, different scattering depths and resolutions result. This allows the detection of nanostructures with a chemical sensitivity. The possibilities of TOF-GISANS are demonstrated by the simple example of polymer nano-dots located on top of a silicon surface. As probed with atomic force microscopy (AFM) the nano-dots exhibit a large characteristic nearest neighbour distance of 545 nm and a surface coverage of 28%. From the analysis of the wavelength dependent data in combination with AFM the mass density of the polymer nano-dots is determined to be equal to the bulk value. A comparison to common single wavelength GISANS experiments is shown.

  20. Polymer boosting effect in the droplet phase studied by small-angle neutron scattering

    CERN Document Server

    Frielinghaus, H; Allgaier, J; Richter, D; Jakobs, B; Sottmann, T; Strey, R

    2002-01-01

    Small-angle neutron-scattering experiments were performed in order to obtain the six partial scattering functions of a droplet microemulsion containing water, decane, C sub 1 sub 0 E sub 4 surfactant and PEP sub 5 -PEO sub 8 sub 0. We systematically varied the contrast around the polymer contrast, where only the polymer becomes visible, and we also measured bulk and film contrasts. With the singular value decomposition method we could extract the desired six partial scattering functions from the 15 measured spectra. We find a sphere-shell-shell structure of the droplets, where the innermost sphere consists of oil, the middle shell of surfactant and the outer shell is a depletion zone where the polymer is almost not present. (orig.)

  1. Small angle neutron scattering study of the initial stage of lysozyme crystallization process

    International Nuclear Information System (INIS)

    Minezaki, Yoshiaki; Tanaka, Ichiro; Niimura, Nobuo; Ataka, Mituo; Katsura, Tatsuo.

    1993-01-01

    Despite the enormous amount of information obtained from atomic resolution crystal data, the difficulties encountered in growing crystals preclude structural X-ray studies for the majority of known isolated proteins. The protein crystal growth process can be studied by electron microscopy and by light scattering, and recently Ataka and Asai have discussed the kinetics on lysozyme crystal growth. We have conducted small angle neutron scattering (SANS) experiments on the time evolution from the initial stages to the visible size of crystallization of hen egg-white lysozyme. SANS from several kinds of solutions have been carried out. The SANS result showed the distinctive change of time evolution. We have also conducted the experiments under various unsaturated conditions using SANS. From these experiments, we found that even under unsaturated conditions, aggregation of lysozyme was found to be started, against the result of light-scattering experiments. (author)

  2. Use of Small-Angle Neutron Scattering in Testing the Stability of Ferrofluids

    CERN Document Server

    Balasoiu, M; Avdeev, M V; Aksenov, V L; Khokhryakov, A A; Bica, L D; Hasegan, D; Török, G; Rosta, L

    2004-01-01

    Stability of ferrofluids - colloidal solutions of magnetic particles covered with surfactants - is the main characteristic that determines the possibility to exploit ferrofluids in different industrial and biomedical applications. Small-angle neutron scattering (SANS) can be effectively used to reveal the aggregation and its change with time in ferrofluids under the action of magnetic field. Despite the fact that in most cases the detailed description of scattering is complicated, one can judge whether a ferrofluid is stable or not by simple analysis of changes in the mean scattering intensity. The advantages of SANS are that industrial samples can be tested without any additional modifications, as well as the real-time experiments with any magnetic load can be easily performed. Examples for a number of ferrofluids are given.

  3. Observation of cross-shaped anisotropy in spin-resolved small-angle neutron scattering

    Science.gov (United States)

    Michels, Andreas; Honecker, Dirk; Döbrich, Frank; Dewhurst, Charles D.; Suzuki, Kiyonori; Heinemann, André

    2012-05-01

    We report the results of spin-resolved small-angle neutron scattering (SANS) experiments on the two-phase nanocrystalline alloy NANOPERM. At a saturating applied magnetic field of 1.27T we observe a cross-shaped angular anisotropy in the non-spin-flip SANS cross section Σ++. This feature—for this class of materials only visible at saturation in Σ++—is attributed to the specific ratio of nuclear to magnetic scattering being smaller than unity. Analysis of the non-spin-flip and spin-flip cross sections provides the nuclear and magnetic SANS and allows us to estimate the magnitude of the respective scattering-length density contrast at the interphase between the nanoparticles and the amorphous magnetic matrix.

  4. Small-angle neutron scattering from poly(NIPA-co-AMPS) gels

    DEFF Research Database (Denmark)

    Travas-Sejdic, J.; Easteal, A.; Knott, R.

    2000-01-01

    was reversed; that is the lower cross-link density, the higher the scattered intensity. Therefore, the role of cross-links at high temperature was to suppress microphase separation. The fitting of the experimental data with the Rabin and Panyukov theory indicated qualitative agreement.......The microstructure of the poly( N-isopropylacrylamide-co-acrylamido- 2-methyl-1-propane sulphonic acid) gel, poly( NIPA-co-AMPS), was investigated as a function of temperature and cross-link density using the small angle neutron scattering technique. The sample temperature was varied in the range...... 30 to 55C. Two different behaviours of poly( NIPA-co-AMPS) gels were observed. At low temperature (30C), the magnitude of the scattered intensity increased with cross-link density suggesting that additional cross-links introduced more inhomogeneities in the gel network. At high temperatures the trend...

  5. Particle size distribution models of small angle neutron scattering pattern on ferro fluids

    International Nuclear Information System (INIS)

    Sistin Asri Ani; Darminto; Edy Giri Rachman Putra

    2009-01-01

    The Fe 3 O 4 ferro fluids samples were synthesized by a co-precipitation method. The investigation of ferro fluids microstructure is known to be one of the most important problems because the presence of aggregates and their internal structure influence greatly the properties of ferro fluids. The size and the size dispersion of particle in ferro fluids were determined assuming a log normal distribution of particle radius. The scattering pattern of the measurement by small angle neutron scattering were fitted by the theoretical scattering function of two limitation models are log normal sphere distribution and fractal aggregate. Two types of particle are detected, which are presumably primary particle of 30 Armstrong in radius and secondary fractal aggregate of 200 Armstrong with polydispersity of 0.47 up to 0.53. (author)

  6. Small-angle neutron scattering study of a monoclonal antibody using free-energy constraints.

    Science.gov (United States)

    Clark, Nicholas J; Zhang, Hailiang; Krueger, Susan; Lee, Hyo Jin; Ketchem, Randal R; Kerwin, Bruce; Kanapuram, Sekhar R; Treuheit, Michael J; McAuley, Arnold; Curtis, Joseph E

    2013-11-14

    Monoclonal antibodies (mAbs) contain hinge-like regions that enable structural flexibility of globular domains that have a direct effect on biological function. A subclass of mAbs, IgG2, have several interchain disulfide bonds in the hinge region that could potentially limit structural flexibility of the globular domains and affect the overall configuration space available to the mAb. We have characterized human IgG2 mAb in solution via small-angle neutron scattering (SANS) and interpreted the scattering data using atomistic models. Molecular Monte Carlo combined with molecular dynamics simulations of a model mAb indicate that a wide range of structural configurations are plausible, spanning radius of gyration values from ∼39 to ∼55 Å. Structural ensembles and representative single structure solutions were derived by comparison of theoretical SANS profiles of mAb models to experimental SANS data. Additionally, molecular mechanical and solvation free-energy calculations were carried out on the ensemble of best-fitting mAb structures. The results of this study indicate that low-resolution techniques like small-angle scattering combined with atomistic molecular simulations with free-energy analysis may be helpful to determine the types of intramolecular interactions that influence function and could lead to deleterious changes to mAb structure. This methodology will be useful to analyze small-angle scattering data of many macromolecular systems.

  7. A medium resolution double crystal based small-angle neutron scattering at Trombay

    International Nuclear Information System (INIS)

    Mazumder, S.; Sen, D.; Saravanan, T.; Vijayaraghavan, P.R.

    2000-10-01

    A double crystal based moderate resolution small-angle neutron scattering instrument has been built and commissioned at the guide tube laboratory of Dhruva reactor, Bhabha Atomic Research Centre, Trombay, India. The instrument consists of a non-dispersive (1, -1) setting of 111 reflections of silicon single crystals with sample between the two crystals. The used neutron wavelength is 0.312 nm. The analyser crystal rotates with smallest step size of 0.0012 deg. At 65 MW of reactor power, the peak count rate of the blank rocking curve is about 55 counts per second at the detector position and the signal to noise ratio is 450 for a typical experiment with sintered alumina. Experiments with sintered alumina specimens reveal that the accessible range of wave vector transfer q is 0.003-0.173 nm -1 . A typical measurement time is about three days. The instrument is calibrated with respect to new high resolution ultra small-angle neutron scattering instrument S18 at the Institute Laue-Langevin in Grenhole, France. (author)

  8. A medium resolution double crystal based small-angle neutron scattering instrument at Trombay

    International Nuclear Information System (INIS)

    Mazumder, S.; Sen, D.; Saravanan, T.; Vijayaraghavan, P.R.

    2001-01-01

    A double crystal-based moderate resolution small-angle neutron scattering instrument has been built and commissioned at the guide laboratory of Dhruva reactor, Bhabha Atomic Research Centre, Trombay, India. The instrument consists of a non-dispersive (1,-1) setting of 111 reflections of silicon single crystals with the sample between the two crystals. The neutron wavelength used is 0.312 nm. At 65 MW of reactor power, the peak count rate of the blank rocking curve is about 55 counts per second at the detector position and the ratio of integrated signal to integrated noise is ∼450 for a typical experiment with sintered aluminia. The accessible range of wave vector transfer q is found to be 0.003-0.173 nm -1 , which corresponds to a range of resolvable real-space dimension of 2000-40 nm, for these specimens. The instrument is calibrated with respect to the high resolution ultra small-angle neutron scattering instrument S18 at the Institute Laue-Langevin in Grenoble, France. (author)

  9. Rheo-small-angle neutron scattering at the National Institute of Standards and Technology Center for Neutron Research

    Science.gov (United States)

    Porcar, L.; Pozzo, D.; Langenbucher, G.; Moyer, J.; Butler, P. D.

    2011-08-01

    We describe the design and operation of a modified commercial rheometer to simultaneously perform rheological measurements and structural studies by small angle neutron scattering (SANS). The apparatus uses a Couette geometry shear cell allowing two of the three scattering planes to be observed by performing experiments in either the radial or tangential geometries. The device enables small angle neutron scattering patterns to be obtained simultaneously with a wide variety of rheological measurements such as stress/strain flow curves, oscillatory deformations, and creep, recovery and relaxation tests, from -20 °C to 150 °C, for samples with viscosities varying by several orders of magnitude. We give a brief report of recent experiments performed on a dispersion of acicular nanoparticles and biopolymer network under stress demonstrating the utility of such measurements. This device has been developed at the National Institute of Standards and Technology's Center for Neutron Research (NCNR) and made available to the complex fluids community as part of the standard sample environment equipment.

  10. Rheo-small-angle neutron scattering at the National Institute of Standards and Technology Center for Neutron Research.

    Science.gov (United States)

    Porcar, L; Pozzo, D; Langenbucher, G; Moyer, J; Butler, P D

    2011-08-01

    We describe the design and operation of a modified commercial rheometer to simultaneously perform rheological measurements and structural studies by small angle neutron scattering (SANS). The apparatus uses a Couette geometry shear cell allowing two of the three scattering planes to be observed by performing experiments in either the radial or tangential geometries. The device enables small angle neutron scattering patterns to be obtained simultaneously with a wide variety of rheological measurements such as stress/strain flow curves, oscillatory deformations, and creep, recovery and relaxation tests, from -20 °C to 150 °C, for samples with viscosities varying by several orders of magnitude. We give a brief report of recent experiments performed on a dispersion of acicular nanoparticles and biopolymer network under stress demonstrating the utility of such measurements. This device has been developed at the National Institute of Standards and Technology's Center for Neutron Research (NCNR) and made available to the complex fluids community as part of the standard sample environment equipment.

  11. Small-angle neutron and dynamic light scattering study of gelatin coacervates

    International Nuclear Information System (INIS)

    Mohanty, B; Bohidar, H.B.; Aswal, V.K.; Goyal, P.S.

    2004-01-01

    The state of intermolecular aggregates and that of folded gelatin molecules could be characterized by dynamic laser light and small-angle neutron scattering experiments, which implied spontaneous segregation of particle sizes preceding coacervation, which is a liquid-liquid phase transition phenomenon. Dynamic light scattering (DLS) data analysis revealed two particle sizes until precipitation was reached. The smaller particles having a diameter of ∼50 nm (stable nanoparticles prepared by coacervation method) were detected in the supernatant, whereas the inter-molecular aggregates having a diameter of ∼400 nm gave rise to coacervation. Small-angle neutron scattering (SANS) experiments revealed that typical mesh size of the networks exist in polymer dense phase (coacervates). Analysis of the SANS structure factor showed the presence of two length scales associated with this system that were identified as the correlation length or mesh size, ξ = 10.6 A of the network and the other is the size of inhomogeneities = 21.4 A. Observations were discussed based on the results obtained from SANS experiments performed in 5% (w/v) gelatin solution at 60 degC (ξ = 50 A, ζ = 113 A) and 5% (w/v) gel at 28 degC (ξ = 47 A, ζ = 115 A) in aqueous phase indicating smaller length scales in coacervate as compared to sol and gel. (author)

  12. Small angle neutron scattering measurements of magnetic cluster sizes in magnetic recorging disks

    CERN Document Server

    Toney, M

    2003-01-01

    We describe Small Angle Neutron Scattering measurements of the magnetic cluster size distributions for several longitudinal magnetic recording media. We find that the average magnetic cluster size is slightly larger than the average physical grain size, that there is a broad distribution of cluster sizes, and that the cluster size is inversely correlated to the media signal-to-noise ratio. These results show that intergranular magnetic coupling in these media is small and they provide empirical data for the cluster-size distribution that can be incorporated into models of magnetic recording.

  13. Small-angle neutron scattering measurements for the characterization of lithographically prepared structures

    International Nuclear Information System (INIS)

    Wu Wenli; Lin, Eric K.; Lin Qinghuang; Angelopolous, Marie

    2001-01-01

    The continuing decrease in feature sizes in the semiconductor and other nanofabrication industries has placed increasingly stringent demands on current microscopy-based techniques to precisely measure both the critical dimensions and the quality (i.e. line-edge roughness) of these structures. Small-angle neutron scattering (SANS) experiments provide a quick, non-destructive, and quantitative measurement of the three-dimensional shape and quality of lithographically prepared structures as fabricated on a silicon substrate. We demonstrate the application of SANS for the characterization of nanoscale structures using periodic 150 nm parallel lines prepared using standard 248 nm photolithographic processes

  14. Small-angle neutron scattering study of high-pressure sintered detonation nanodiamonds

    International Nuclear Information System (INIS)

    Kidalov, S. V.; Shakhov, F. M.; Lebedev, V. T.; Orlova, D. N.; Grushko, Yu. S.

    2011-01-01

    The structure of detonation diamonds sintered at a high pressure (7 GPa) and temperatures of 1200–1700°C has been investigated by small-angle neutron scattering. It is shown that sintering leads to an increase in the particle size from 6 to 30 nm and established that this increase is due to the chainlike oriented attachment of particles. This study supplements the oriented-attachment model, which was suggested based on the X-ray diffraction spectra of detonation nanodiamonds (DNDs) sintered under the same conditions.

  15. Small angle neutron scattering data of polymer electrolyte membranes partially swollen in water

    Directory of Open Access Journals (Sweden)

    Yue Zhao

    2016-06-01

    Full Text Available In this article, we show the small-angle neutron scattering (SANS data obtained from the polymer electrolyte membranes (PEMs equilibrated at a given relative humidity. We apply Hard-Sphere (HS structure model with Percus–Yervick interference interactions to analyze the dataset. The molecular structure of these PEMs and the morphologies of the fully water-swollen membranes have been elucidated by Zhao et al. “Elucidation of the morphology of the hydrocarbon multi-block copolymer electrolyte membranes for proton exchange fuel cells” [1].

  16. Small angle neutron scattering data of polymer electrolyte membranes partially swollen in water.

    Science.gov (United States)

    Zhao, Yue; Yoshida, Miru; Oshima, Tatsuya; Koizumi, Satoshi; Rikukawa, Masahiro; Szekely, Noemi; Radulescu, Aurel; Richter, Dieter

    2016-06-01

    In this article, we show the small-angle neutron scattering (SANS) data obtained from the polymer electrolyte membranes (PEMs) equilibrated at a given relative humidity. We apply Hard-Sphere (HS) structure model with Percus-Yervick interference interactions to analyze the dataset. The molecular structure of these PEMs and the morphologies of the fully water-swollen membranes have been elucidated by Zhao et al. "Elucidation of the morphology of the hydrocarbon multi-block copolymer electrolyte membranes for proton exchange fuel cells" [1].

  17. Direct Observation Of Nanoparticle-Surfactant Interactions Using Small Angle Neutron Scattering

    Science.gov (United States)

    Kumar, Sugam; Aswal, V. K.

    2010-12-01

    Interactions of anionic silica nanoparticles with anionic, cationic and nonionic surfactants have directly been studied by contrast variation small angle neutron scattering (SANS). The measurements are performed on 1 wt% of both silica nanoparticles and surfactants of anionic sodium dodecyle sulphate (SDS), cationic dodecyltrimethyl ammonium bromide (DTAB) and non-ionic polyoxyethylene 10 lauryl ether (C12E10) in aqueous solution. We show that there is no direct interaction in the case of SDS with silica particles, whereas strong interaction for DTAB leads to the aggregation of silica particles. The interaction of C12E10 is found through the micelles adsorbed on the silica particles.

  18. Small angle X-ray and neutron scattering on cadmium sulfide nanoparticles in silicate glass

    Science.gov (United States)

    Kuznetsova, Yu. V.; Rempel, A. A.; Meyer, M.; Pipich, V.; Gerth, S.; Magerl, A.

    2016-08-01

    Small angle X-ray and neutron scattering on Cd and S doped glass annealed at 600 °C shows after the first 12 h nucleation and growth of spherical CdS nanoparticles with a radius of up to 34±4 Å. After the nucleation is completed after 24 h, further growth in this amorphous environment is governed by oriented particle attachment mechanism as found for a liquid medium. Towards 48 h the particle shape has changed into spheroidal with short and long axis of 40±2 Å and 120±2 Å, respectively.

  19. Use of Small Angle Neutron Scattering to Study Various Properties of Wool and Mohair Fibres

    Science.gov (United States)

    Franklyn, C. B.; Török, Gy.

    2011-12-01

    To maintain a competitive edge in the wool and mohair industry, a detailed knowledge and understanding of the properties of wool fibres is essential. Standard techniques are used to determine fibre diameter, length and strength; however, properties such as hydroscopicity, lustre and changes in fibre structure following chemical or mechanical treatment are not so well understood. The unique capabilities of small angle neutron scattering to study changes in the supermolecular structure of wool fibres, particularly at the level of the microfibril-matrix complex, have been used to provide previously unknown features of the fibres. The results of these studies are presented.

  20. Microstructural Investigations by Small Angle Scattering of Neutrons and X-rays

    Science.gov (United States)

    Fiori, F.; Spinozzi, F.

    Small angle scattering techniques [77, 103, 106, 156, 242, 254] (SANS when using neutron beams or SAXS when using conventional X-ray radiation sources or synchrotron radiation) are experimental methods allowing the determination of structural features, such as size and volume fraction, of matrix inhomogeneities in a huge variety of materials, covering studies from biochemistry and biophysics to applied and industrial research. The order of magnitude of the size of objects that can be detected is in the approximate range 1-103 nm, but with special methods (Ultra-SANS) also objects up to tens of micrometerscan be investigated.

  1. Small-angle neutron scattering study of high-pressure sintered detonation nanodiamonds

    Energy Technology Data Exchange (ETDEWEB)

    Kidalov, S. V.; Shakhov, F. M., E-mail: fedor.shakhov@mail.ioffe.ru [Ioffe Physical-Technical Institute of the Russian Academy of Sciences (Russian Federation); Lebedev, V. T.; Orlova, D. N.; Grushko, Yu. S. [Russian Academy of Sciences, Konstantinov St. Petersburg Nuclear Physics Institute (Russian Federation)

    2011-12-15

    The structure of detonation diamonds sintered at a high pressure (7 GPa) and temperatures of 1200-1700 Degree-Sign C has been investigated by small-angle neutron scattering. It is shown that sintering leads to an increase in the particle size from 6 to 30 nm and established that this increase is due to the chainlike oriented attachment of particles. This study supplements the oriented-attachment model, which was suggested based on the X-ray diffraction spectra of detonation nanodiamonds (DNDs) sintered under the same conditions.

  2. Investigation of the cluster structure in aqueous suspensions of nanodiamonds by small-angle neutron scattering

    Directory of Open Access Journals (Sweden)

    L. A. Bulavin

    2015-07-01

    Full Text Available The paper presents the results of the structural study of various types of the water-detonation nanodiamond liquid systems, which are obtained by small-angle scattering of thermal neutrons. It was shown that in the mass fraction range (0.3 - 1.8 % the experimental spectra are well described by a two-level model of unified exponential/power-law approach. The resulting structural parameters allowed us to estimate the aggregation number in the studied systems. Sizes of the nanodiamond particles and their clusters are found as well as the fractal dimension of the latter.

  3. Small angle neutron scattering comparative investigation of Inconel 738 samples submitted to different ageing treatments

    International Nuclear Information System (INIS)

    Rogante, M.; Lebedev, V.T.

    2008-01-01

    Inconel 738 samples submitted to different annealing temperatures and ageing times have been investigated by small angle neutron scattering (SANS), with the aim to study precipitates phases microstructural evolution and material behaviour. The same material is a γ' (Ni 3 Al, Ti) precipitation hardened nickel base superalloy adopted at high temperatures in aggressive environments, and it has found applications over a very wide range of temperature. Information on the thermal treatment effects have been obtained, in particular concerning precipitate size and volume fraction distributions. The results contribute to confirm the adopted method to a level of industrial applicability in the considered sector

  4. Amorphous soft-magnetic ribbons studied by ultra-small-angle polarized neutron scattering

    International Nuclear Information System (INIS)

    Badurek, G; Jericha, E; Groessinger, R; Sato-Turtelli, R

    2010-01-01

    When we investigated the magnetic structure of a variety of soft-magnetic amorphous ribbons by means of ultra-small-angle neutron scattering (USANSPOL) we were confronted with one particularly interesting Fe 65.7 Co 18 Si 0.8 B 15.5 ribbon, provided by VAC Hanau. Due to a special thermal treatment during production a field- and stress-induced transverse domain texture was expected. Although the USANSPOL technique encountered its resolution limits during the investigation of this specific sample ribbon, such a texture could indeed be verified.

  5. Investigation of the cluster structure in aqueous suspensions of nanodiamonds by small-angle neutron scattering

    International Nuclear Information System (INIS)

    Bulavin, L.A.; Tomchuk, O.V.; Avdeev, M.V.

    2015-01-01

    The paper presents the results of the structural study of various types of the water-detonation nanodiamond liquid systems, which are obtained by small-angle scattering of thermal neutrons. It was shown that in the mass fraction range (0.3/1.8) % the experimental spectra are well described by a two-level model of unified exponential/power-law approach. The resulting structural parameters allowed us to estimate the aggregation number in the studied systems. Sizes of the nanodiamond particles and their clusters are found as well as the fractal dimension of the latter

  6. Small-angle neutron and X-ray scattering studies of supraatomic structure of synthetic quartz irradiated by fast neutrons

    International Nuclear Information System (INIS)

    Lebedev, V.M.; Lebedev, V.T.; Orlov, S.P.; Golubkov, V.V.; Pevzner, B.Z.; Tolstikhin, I.N.

    2008-01-01

    Quartz nanostructures have been simulated for the investigation into diffusion of gases in the Earth crust. The nanostructure of synthetic quartz irradiated by fast neutrons with energy E n >0.1 MeV was studied by neutron and X-ray small-angle scattering. The range of neutron fluence is of 10 17 cm -2 up to 2x10 -2 0 cm -2 . In the irradiated samples the different kinds of defects such as point-like, extended linear (dislocations) and globular (size ∼100 nm, amorphous phase nuclei) were observed. The density of highly irradiated quartz (fluence 2x10 20 cm -2 ) is shown to decrease by 0.39 g/cm 2 and reach the magnitude of 2.260 g/cm 2 corresponding to 100% metamict phase. The first results of model structures helium saturation have been received [ru

  7. Characterisation of the polarised neutron beam at the small angle scattering instrument SANS-I with a polarised proton target

    International Nuclear Information System (INIS)

    Aswal, V.K.; Brandt, B. van den; Hautle, P.; Kohlbrecher, J.; Konter, J.A.; Michels, A.; Piegsa, F.M.; Stahn, J.; Petegem, S. van; Zimmer, O.

    2008-01-01

    A transmission neutron polariser (Fe/Si supermirror) has been successfully implemented in the small angle neutron scattering instrument SANS-I at the SINQ neutron source. The polariser is needed for investigations of magnetic nanostructures as well as for spin contrast variation techniques relying on the spin-dependent neutron scattering length of polarised nuclei. The V-shaped polariser is installed in the first section of the collimator system of the SANS instrument and its performance is optimised for neutrons with a wavelength between 0.5 and 1.0 nm. For a precise polarisation analysis of a beam with selectable incident divergence, such as in SANS experiments, an opaque spin filter is ideal. We used a solid polarised proton target exploiting the strong spin-dependent neutron scattering cross-section of hydrogen and determined the neutron beam polarisation to a precision of δp/p∼0.5% for different collimations in a broad wavelength band

  8. Characterisation of the polarised neutron beam at the small angle scattering instrument SANS-I with a polarised proton target

    Science.gov (United States)

    Aswal, V. K.; van den Brandt, B.; Hautle, P.; Kohlbrecher, J.; Konter, J. A.; Michels, A.; Piegsa, F. M.; Stahn, J.; Van Petegem, S.; Zimmer, O.

    2008-02-01

    A transmission neutron polariser (Fe/Si supermirror) has been successfully implemented in the small angle neutron scattering instrument SANS-I at the SINQ neutron source. The polariser is needed for investigations of magnetic nanostructures as well as for spin contrast variation techniques relying on the spin-dependent neutron scattering length of polarised nuclei. The V-shaped polariser is installed in the first section of the collimator system of the SANS instrument and its performance is optimised for neutrons with a wavelength between 0.5 and 1.0 nm. For a precise polarisation analysis of a beam with selectable incident divergence, such as in SANS experiments, an opaque spin filter is ideal. We used a solid polarised proton target exploiting the strong spin-dependent neutron scattering cross-section of hydrogen and determined the neutron beam polarisation to a precision of δp/p˜0.5% for different collimations in a broad wavelength band.

  9. Studies on polymer thin film structure by X-ray and neutron reflectivity and grazing incidence small angle scattering

    International Nuclear Information System (INIS)

    Ogawa, Hiroki; Kanaya, Toshiji

    2011-01-01

    We have reviewed structure studies of polymer thin films using synchrotron radiation X-ray and neutron reflectivity as well as recently developed grazing incidence small-angle X-ray and neutron scattering, including studies on polymer thin films with embedded ordered nanometer cells, distribution of glass transition temperature Tg in thin polystyrene films, and dewetting process of polymer blend thin films. (author)

  10. Modern tendencies in development of small-angle neutron scattering in studying the structure of biological macromolecules

    International Nuclear Information System (INIS)

    Serdyuk, I.N.

    1997-01-01

    The paper presents a brief discussion of the tendencies in development of the theory and practical application of small-angle neutron scattering for studying the structure of biological macromolecules. Special attention is focused on the studies carried out in the Laboratory of Neutron Physics at the unique Ibr-2 pulse reactor in Dubna

  11. Investigation of polydisperse, disordered, and fractal systems by small-angle x-ray and neutron scattering

    International Nuclear Information System (INIS)

    Schmidt, P.W.; Tang, Y.; Roell, A.; Steiner, M.; Hoehr, A.; Neumann, H.B.

    1990-01-01

    Small-angle x-ray and neutron scattering are useful methods for investigating the structure of materials on a scale from about 10 to 2000 A. Some experimental procedures and methods of data analysis for small-angle scattering are outlined, and the use of small-angle scattering for studies of polydisperse systems (i.e., systems of particles of different size) of independently scattering particles is reviewed. Some general properties of the small-angle scattering from mass and surface fractals are discussed, and some applications of these concepts in recent experimental studies are presented. Results obtained in calculations of the small-angle scattering from a model of a surface are summarized. (author) 3 figs., 18 refs

  12. Branch Point Withdrawal in Elongational Startup Flow by Time-Resolved Small Angle Neutron Scattering

    KAUST Repository

    Ruocco, N.

    2016-05-27

    We present a small angle neutron scattering (SANS) investigation of a blend composed of a dendritic polymer and a linear matrix with comparable viscosity in start-up of an elongational flow at Tg + 50. The two-generation dendritic polymer is diluted to 10% by weight in a matrix of a long well-entangled linear chains. Both components consist of mainly 1,4-cis-polyisoprene but differ in isotopic composition. The resulting scattering contrast is sufficiently high to permit time-resolved measurements of the system structure factor during the start-up phase and to follow the retraction processes involving the inner sections of the branched polymer in the nonlinear deformation response. The outer branches and the linear matrix, on the contrary, are in the linear deformation regime. The linear matrix dominates the rheological signature of the blend and the influence of the branched component can barely be detected. However, the neutron scattering intensity is predominantly that of the (branched) minority component so that its dynamics is clearly evident. In the present paper, we use the neutron scattering data to validate the branch point withdrawal process, which could not be unambiguously discerned from rheological measurements in this blend. The maximal tube stretch that the inner branches experience, before the relaxed outer arm material is incorporated into the tube is determined. The in situ scattering experiments demonstrate for the first time the leveling-off of the strain as the result of branch point withdrawal and chain retraction directly on the molecular level. We conclude that branch point motion in the mixture of architecturally complex polymers occurs earlier than would be expected in a purely branched system, presumably due to the different topological environment that the linear matrix presents to the hierarchically deep-buried tube sections. © 2016 American Chemical Society.

  13. Characterization of Nanocellulose Using Small-Angle Neutron, X-ray, and Dynamic Light Scattering Techniques.

    Science.gov (United States)

    Mao, Yimin; Liu, Kai; Zhan, Chengbo; Geng, Lihong; Chu, Benjamin; Hsiao, Benjamin S

    2017-02-16

    Nanocellulose extracted from wood pulps using TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation and sulfuric acid hydrolysis methods was characterized by small-angle neutron scattering (SANS), small-angle X-ray scattering (SAXS), and dynamic light scattering (DLS) techniques. The dimensions of this nanocellulose (TEMPO-oxidized cellulose nanofiber (TOCN) and sulfuric acid hydrolyzed cellulose nanocrystal (SACN)) revealed by the different scattering methods were compared with those characterized by transmission electron microscopy (TEM). The SANS and SAXS data were analyzed using a parallelepiped-based form factor. The width and thickness of the nanocellulose cross section were ∼8 and ∼2 nm for TOCN and ∼20 and ∼3 nm for SACN, respectively, where the fitting results from SANS and SAXS profiles were consistent with each other. DLS was carried out under both the V V mode with the polarizer and analyzer parallel to each other and the H V mode having them perpendicular to each other. Using rotational and translational diffusion coefficients obtained under the H V mode yielded a nanocellulose length qualitatively consistent with that observed by TEM, whereas the length derived by the translational diffusion coefficient under the V V mode appeared to be overestimated.

  14. Comments on 'Design optimization of a small-angle neutron scattering spectrometer'

    International Nuclear Information System (INIS)

    Mildner, D.F.R.

    1990-01-01

    Margaca, Falcao, Salgado and Carvahlo have recently discussed the design parameters of a small-angle scattering spectrometer. They claim to have shown that the instrument can be optimized for constant angular resolution and a fixed neutron source area, such that the detector count rate is higher than that obtained with a spectrometer optimized for a fixed total length and having the same angular resolution. They also claim that the relative gain in intensity depends upon the size of the neutron emitting surface available to the spectrometer. The initial assumptions made by the authors are too constrained to be generally applicable and therefore misleading conclusions could be drawn, and in fact the equal path length arrangement is optimum. (orig.)

  15. Stroboscopic Small Angle Neutron Scattering Investigations of Microsecond Dynamics in Magnetic Nanomaterials

    Science.gov (United States)

    Wiedenmann, A.; Gähler, R.; May, R. P.; Keiderling, U.; Habicht, K.; Prévost, S.; Klokkenburg, M.; Erné, B.; Kohlbrecher, J.

    Time-resolved Small Angle Neutron Scattering (SANS) techniques have recently been developed that allow ordering and relaxation processes of magnetic moments in nanoparticles to be monitored. In stroboscopic experiments, time-frame data acquisition has been synchronized with a periodic external magnetic field. Slow relaxation of magnetic particle moments onto equilibrium has been studied in periods of the order of 30 s after switch off a static field. By applying a sine-wave modulated magnetic field at frequencies above 50 Hz, the time-resolved SANS response to a forced oscillation could be analyzed. When a continuous neutron flux was used in conventional SANS, the shortest accessible time range was limited to about 3 ms resulting from the wavelength spread. A breakthrough of time resolution into the micro-second range was achieved with the pulsed frame overlap TISANE technique, which allows us to exploit a dynamical range similar to that of X-ray photon-correlation spectroscopy.

  16. Structure investigations on Portland cement paste by small angle neutron scattering

    International Nuclear Information System (INIS)

    Dragolici, C. A.; Len, A.

    2003-01-01

    Portland cement pastes consist of many crystalline and non-crystalline phases in various ranges of sizes (nm and mm scale). The crystalline phases are embedded in amorphous phases of the hydration products. We investigated the structural changes of hydrating phases in the time interval of 1-30 days at Budapest Neutron Center's SANS diffractometer. The small angle neutron scattering of Portland cements prepared with a water-to-cement ratio from 0,3 to 0,8 gave us information about the microstructure changes in the material. Fractals were a suitable way for structure modelling. The variation of fractals size depending on the preparation-to-measurement time interval and water-to-cement ratio could be observed. (authors)

  17. Neutron scattering. Experiment manuals

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2010-07-01

    The following topics are dealt with: The thermal triple axis spectrometer PUMA, the high-resolution powder diffractometer SPODI, the hot single-crystal diffractometer HEiDi for structure analysis with neutrons, the backscattering spectrometer SPHERES, neutron polarization analysis with tht time-of-flight spectrometer DNS, the neutron spin-echo spectrometer J-NSE, small-angle neutron scattering with the KWS-1 and KWS-2 diffractometers, the very-small-angle neutron scattering diffractrometer with focusing mirror KWS-3, the resonance spin-echo spectrometer RESEDA, the reflectometer TREFF, the time-of-flight spectrometer TOFTOF. (HSI)

  18. Neutron scattering. Experiment manuals

    International Nuclear Information System (INIS)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner

    2010-01-01

    The following topics are dealt with: The thermal triple axis spectrometer PUMA, the high-resolution powder diffractometer SPODI, the hot single-crystal diffractometer HEiDi for structure analysis with neutrons, the backscattering spectrometer SPHERES, neutron polarization analysis with tht time-of-flight spectrometer DNS, the neutron spin-echo spectrometer J-NSE, small-angle neutron scattering with the KWS-1 and KWS-2 diffractometers, the very-small-angle neutron scattering diffractrometer with focusing mirror KWS-3, the resonance spin-echo spectrometer RESEDA, the reflectometer TREFF, the time-of-flight spectrometer TOFTOF. (HSI)

  19. Neutron focusing optics for low-resolution small-angle scattering

    International Nuclear Information System (INIS)

    Mildner, D.F.R.

    1994-01-01

    Small-angle neutron scattering instruments use large source and sample areas with long flight paths to obtain the necessary resolution. Increased count rates may be obtained using collimators that converge to a point on the detector. Further increases may be obtained by converging guides in the form of a focusing lens. A low-resolution small-angle scattering instrument that uses converging capillary fibers as a focusing lens is proposed. Such a device requires the use of a detector that has a fine spatial resolution, perhaps less than 0.1 mm. Expressions are derived for the resolution and the intensity optimized for such an instrument. The relationship is determined between the guide dimensions, the focal length and the critical angle of the internal coating of the individual fiber channels. The critical angle of the focusing lens dominates the resolution, and such an instrument is useful only for low-resolution measurements. However, the greatly reduced length is only valuable if there is a high-resolution detector to match the dimensions of the guide. Despite its low resolution, such an instrument might eventually be useful for survey or characterization measurements. (orig.)

  20. The challenge of observation on livings things by employing an ultra small-angle neutron scattering method

    International Nuclear Information System (INIS)

    Koizumi, Satoshi; Motokawa, Ryuhei; Iwase, Hiroki; Miyamoto, Nobuyoshi; Tanaka, Kazuhiro; Masui, Tomomi; Iida, You; Yue, Zhao; Chiba, Kaori; Kumada, Takayuki; Yamaguchi, Daisuke; Hashimoto, Takeji

    2007-01-01

    To address the question as to how small-angle scattering is effectively applied to the cell, i.e., a hierarchically ordered system comprising multi-components of macro and small molecules, the size of which ranges from 100 μm to several μm, we reconstructed SANS-J (pinhole small-angle neutron scattering spectrometer at research reactor JRR3, Tokai) to focusing and polarized neutron small-angle spectrometer (SANS-J-II), by employing focusing neutron lenses and high resolution photomultiplier. Consequently, an accessible minimum wave number q min was improved from 3x10 -3 A -1 to medium ultra-small angle scattering of 3x10 -4 A -1 . The focusing USANS method, thus developed, is crucial to fill the gap in wave number q between those covered by a double crystal method and by a conventional pin-hole method. (author)

  1. Analysis of heterogeneity of polymer systems from the data of small angle X-ray and neutron scattering

    International Nuclear Information System (INIS)

    Agamalyan, M.M.

    1989-01-01

    The possibility of determination of the chemical composition of supermolecular formations in blocks of polymer systems by comparison of squares of relative contrasts measured experimentally using small-angle X-ray and neutron scattering with theoretically calculated ones is discussed. The efficiency of this technique is related with large difference in the scattering capacity of density heterogeneities of hydrogen-containing media towards X-ray and neutrons. The technique is illustrated with some examples

  2. Small-angle neutron scattering and molecular dynamics structural study of gelling DNA nanostars

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Castanon, J.; Bomboi, F. [Sapienza–Università di Roma, P.le A. Moro 5, 00185 Roma (Italy); Rovigatti, L. [Rudolf Peierls C.T.P., University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna (Austria); Zanatta, M. [Dipartimento di Fisica, Università di Perugia, Via Pascoli, 06123 Perugia (Italy); CNR-ISC, UOS Sapienza–Università di Roma, I-00186 Roma (Italy); Paciaroni, A. [Dipartimento di Fisica, Università di Perugia, Via Pascoli, 06123 Perugia (Italy); Comez, L. [Dipartimento di Fisica, Università di Perugia, Via Pascoli, 06123 Perugia (Italy); IOM-CNR, UOS Perugia c/o Dipartimento di Fisica e Geologia, Università di Perugia, Via Pascoli, 06123 Perugia (Italy); Porcar, L. [Institut Laue-Langevin, 71 Avenue des Martyrs, CS 20156, 38042 Grenoble Cedex 9 (France); Jafta, C. J. [Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Fadda, G. C. [Laboratoire Léon Brillouin, LLB, CEA Saclay, 91191 Gif-sur-Yvette Cedex (France); Bellini, T. [Department of Medical Biotechnology and Translational Medicine, Università di Milano, I-20133 Milano (Italy); Sciortino, F., E-mail: francesco.sciortino@uniroma1.it [Sapienza–Università di Roma, P.le A. Moro 5, 00185 Roma (Italy); CNR-ISC, UOS Sapienza–Università di Roma, I-00186 Roma (Italy)

    2016-08-28

    DNA oligomers with properly designed sequences self-assemble into well defined constructs. Here, we exploit this methodology to produce bulk quantities of tetravalent DNA nanostars (each one composed of 196 nucleotides) and to explore the structural signatures of their aggregation process. We report small-angle neutron scattering experiments focused on the evaluation of both the form factor and the temperature evolution of the scattered intensity at a nanostar concentration where the system forms a tetravalent equilibrium gel. We also perform molecular dynamics simulations of one isolated tetramer to evaluate the form factor numerically, without resorting to any approximate shape. The numerical form factor is found to be in very good agreement with the experimental one. Simulations predict an essentially temperature-independent form factor, offering the possibility to extract the effective structure factor and its evolution during the equilibrium gelation.

  3. Kappa-casein micelles: structure, interaction and gelling studied by small-angle neutron scattering.

    Science.gov (United States)

    de Kruif, C G; May, R P

    1991-09-01

    Small-angle neutron scattering (SANS) measurements on dilute and concentrated dispersions of kappa-casein micelles in a buffer at pH = 6.7 were made using the D11 diffractometer in Grenoble. Results indicate that the micelles have a dense core with a fluffy outer layer. This outer layer appears to give rise to a steeply repulsive interaction on contact. In fact, the hard-sphere model best fits the measured scattering intensities. Adding chymosin to the dispersion initiated a fractal flocculation of the micelles and consecutively a coalescence of the micelles. This unexpected second process resembled that of spinodal demixing. The dispersion phase thus separates into a water and a protein phase on a time scale of hours. The observed phenomona contribute to the understanding of the cheese-making process.

  4. Small angle neutron scattering study on star di-block copolymers

    International Nuclear Information System (INIS)

    Ertugrul, O.

    2006-01-01

    Determining structural properties, phase transitions and stability of polymer mixtures is very important to produce new materials with desired and interesting properties. Small Angle Neutron Scattering Technique (SANS) has been one of the most powerful and intensely used methods for the characterization of polymers for last decades, m this study, we use a model based on Gaussian Random Phase Approximation (RPA) to describe Star Di-block Copolymers (SDC) mixtures with homo-polymers. We could able to predict the miscibility and phase transitions of the various mixtures along with their structure factors, producing a thermodynamic picture of the system. Also the results suggest that scattering intensity will be dictated by the structure factor of the core or shell parts of star polymer only, which depends on the homo-polymer type of the mixture

  5. SEC-SANS: size exclusion chromatography combined in situ with small-angle neutron scattering.

    Science.gov (United States)

    Jordan, Ashley; Jacques, Mark; Merrick, Catherine; Devos, Juliette; Forsyth, V Trevor; Porcar, Lionel; Martel, Anne

    2016-12-01

    The first implementation and use of an in situ size exclusion chromatography (SEC) system on a small-angle neutron scattering instrument (SANS) is described. The possibility of deploying such a system for biological solution scattering at the Institut Laue-Langevin (ILL) has arisen from the fact that current day SANS instruments at ILL now allow datasets to be acquired using small sample volumes with exposure times that are often shorter than a minute. This capability is of particular importance for the study of unstable biological macromolecules where aggregation or denaturation issues are a major problem. The first use of SEC-SANS on ILL's instrument D22 is described for a variety of proteins including one particularly aggregation-prone system.

  6. Small angle neutron scattering study on short and long chain phosphatidylcholine mixture in trehalose solution

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hiroshi [Department of Physics, Gunma University, Maebashi, Gunma (Japan)

    2001-03-01

    Trehalose protects cells and proteins against various stresses due to low temperatures or dryness. In order to clarify the molecular mechanism of cryoprotective function of trehalose, we have studied the interaction between trehalose and phosphatidylcholine (PC) which is a main lipid component of cell membranes. In this study, the structural change of a binary PC mixture by the presence of trehalose was investigated by means of small angle neutron scattering. The PC binary mixture studied contains dihexanoyl-PC (diC{sub 6}PC) and dihexadecy-PC (DHPC). The former has short hydrocarbon chains and the latter has long hydrocarbon chains. The scattering profiles from the DHPC/diC{sub 6}PC mixture were changed, depending on trehalose concentrations. This change can be interpreted as suggesting that the presence of trehalose reduces the interfacial area between water and PCs. (author)

  7. Structural Formation of Huntingtin Exon 1 Aggregates Probed by Small-Angle Neutron Scattering

    Science.gov (United States)

    Stanley, Christopher B.; Perevozchikova, Tatiana; Berthelier, Valerie

    2011-01-01

    In several neurodegenerative disorders, including Huntington's disease, aspects concerning the earliest of protein structures that form along the aggregation pathway have increasingly gained attention because these particular species are likely to be neurotoxic. We used time-resolved small-angle neutron scattering to probe in solution these transient structures formed by peptides having the N-terminal sequence context of mutant huntingtin exon 1. We obtained snapshots of the formed aggregates as the kinetic reaction ensued to yield quantitative information on their size and mass. At the early stage, small precursor species with an initial radius of gyration of 16.1 ± 5.9 Å and average mass of a dimer to trimer were monitored. Structural growth was treated as two modes with a transition from three-dimensional early aggregate formation to two-dimensional fibril growth and association. Our small-angle neutron scattering results on the internal structure of the mature fibrils demonstrate loose packing with ∼1 peptide per 4.75 Å β-sheet repeat distance, which is shown to be quantitatively consistent with a β-helix model. This research provides what we believe to be new insights into the structures forming along the pathway of huntingtin exon 1 aggregation and should assist in determining the role that precursors play in neuronal toxicity. PMID:21575585

  8. Insights into molecular architecture of terpenes using small angle neutron scattering

    Science.gov (United States)

    Rai, Durgesh K.; Annamraju, Aparna; Pingali, Sai Venkatesh; O'Neill, Hugh M.; Mewalal, Ritesh; Gunter, Lee E.; Tuskan, Gerald A.

    Understanding macromolecular architectures is vital to engineering prospective terpene candidates for advanced biofuels. Eucalyptus plants store terpenes in specialized cavity-like structures in the leaves called oil glands, which comprises of volatile (VTs) and non-volatile (NVTs) terpenes. Using small-angle neutron scattering, we have investigated the structure and phase behavior of the supramolecular assembly formed by Geranyl beta-D-glucoside (GDG), a NVT and compare the results with that of beta-octyl glucoside (BOG). The formation of micellar structures was observed in the concentration range of 0.5-5 v/v% in water using small angle neutron scattering (SANS) where Schultz sphere model was used in quantifying structural parameters of micelles. SANS studies determine that GDG and BOG behave like amphiphiles forming micellar structures in aqueous solution. The micelles swell upon addition of alpha-Pinene (AP) indicating partition to the core region of the micelles. The general behavior of the micellar growth after partitioning of AP to form thermodynamically stable sizes varies with the NVT concentration. Our studies reveal that the presence of steric hindrance in the GDG via the unsaturated bonds could help stabilize VTs inside the oil glands. LDRD project LOIS ID 7428, SNS, CSMB, HFIR, ORNL, DOE Office of Science User Facilities.

  9. In-situ vapor small angle neutron scattering of sulfonated polyarylenethioethersulfone random copolymer (SPTES 70) fuel cells membrane

    International Nuclear Information System (INIS)

    Yoonessi, Mitra; Bai, Zongwu; Wheeler, Robert; Dang, Thuy D

    2014-01-01

    Highly sulfonated polyarylenethioethersulfone copolymer (SPTES 70) with excellent thermal stability, high proton conductivity and good mechanical properties is an excellent candidate as high temperature fuel cells membrane. The morphology of the SPTES 70 was examined with in situ vapor small angle neutron scattering (iVSANS), and transmission electron microscopy. An experimental neutron contrast match point was obtained with swelling SPTES 70 in a series of D 2 O/H 2 O ratios and compared with the calculated scattering contrast. The calculated scattering length density of SPTES 70 was in excellent agreement with the experiment scattering length density. Small angle neutron scattering (SANS) data of the magnesium, calcium, and silver exchanged hydrated SPTES 70 membranes exhibited nanostructured morphology which was compared with the reported nanostructure of D 2 O hydrated SPTES 70. SANS data showed that the average ionic domain size changes with the size and valence of the counter ion. (paper)

  10. Design of a new time-of-flight small-angle neutron scattering instrument at CPHS

    International Nuclear Information System (INIS)

    Huang, T.C.; Gong, H.; Shao, B.B.; Wang, D.; Zhang, X.Z.; Zhang, K.; Wei, J.; Wang, X.W.; Guan, X.L.; Loong, C.-K.; Tao, J.Z.; Zhou, L.; Ke, Y.B.

    2012-01-01

    A new time-of-flight (TOF) small-angle neutron scattering (SANS) diffractometer is to be built at the Compact Pulsed Hadron Source (CPHS) of Tsinghua University, China. This SANS project strives to serve two purposes: its instrumental design, fabrication and optimization will help glean valuable scientific and engineering experiences; and its utilization will help promote fruitful domestic user programs on research of large structures in advanced materials using neutrons. The design draws experiences from other TOF SANS instruments, particularly that of the long-pulse LENS of Indiana University and also considers the source features at CPHS. The design team enjoyed the guidance and assistance from experts through international collaborations. For simultaneous collection of scattering data in the Q-range (∼7×10 -3 -1 ) with reasonable Q-resolution and high efficiency, this instrument is designed to use large area detector (1×1 m 2 ) and broad wavelength bandwidth (1-10 Å) within the first frame. It also pays attention to possible use of optical devices such as neutron guides, focusing lenses and novel detectors.

  11. Structure of the capsid of Kilham rat virus from small-angle neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Wobbe, C.R.; Mitra, S.; Ramakrishnan, V.

    1984-12-18

    The structure of empty capsids of Kilham rat virus, an autonomous parvovirus with icosahedral symmetry, was investigated by small-angle neutron scattering. From the forward scatter, the molecular weight was determined to be 4.0 x 10(6), and from the Guinier region, the radius of gyration was found to be 105 A in D2O and 104 A in H/sub 2/O. On the basis of the capsid molecular weight and the molecular weights and relative abundances of the capsid proteins, the authors propose that the capsid has a triangulation number of 1. Extended scattering curves and mathematical modeling revealed that the capsid consists of two shells of protein, the inner shell extending from 58 to 91 A in D2O and from 50 to 91 A in H/sub 2/O and containing 11% of the capsid scattering mass, and the outer shell extending to 121 A in H/sub 2/O and D2O. The inner shell appears to have a higher content of basic amino acids than the outer shell, based on its lower scattering density in D2O than in H/sub 2/O. The authors propose that all three capsid proteins contribute to the inner shell and that this basic region serves DNA binding and partial charge neutralization functions.

  12. Fine scale microstructure in cast and aged duplex stainless steels investigated by small angle neutron scattering

    International Nuclear Information System (INIS)

    Epperson, J.E.; Lin, J.S.; Spooner, S.

    1986-02-01

    Small angle neutron scattering (SANS) allows clustering phenomena to be studied in systems for which the constituent atoms do not differ greatly in atomic number. This investigation used SANS to characterize the fine scale microstructure in two cast and aged duplex stainless steels; aging times extended up to eight years. The steels differed in ferrite content by about a factor of two. The scattering at lowest q was dominated by magnetic scattering effects associated with the ferrite phase. In the range 0.025 less than or equal to q less than or equal to 0.2A -1 , additional scattering due to a precipitating phase rich in Ni and Si was observed. This scattering was rather intense and revealed a volume fraction of precipitate, in the ferrite, estimated to be 12 to 18% after long time aging. After about 70,000 hours at 400 0 C, there were about 10 18 precipitate particles per cm 3 some 50A in mean diameter, and they were distributed in a nonrandom manner, i.e., spatially, short-range-ordered. This investigation suggests that after aging some 70,000 hours at 400 0 C, the precipitate in the ferrite phase is undergoing Ostwald ripening. The present data are insufficient to indicate at what time this ripening process began

  13. Small-angle scattering, topography and radiography

    International Nuclear Information System (INIS)

    Schelten, J.

    1978-01-01

    A table is given showing scattering and imaging methods for X-rays and neutrons, followed, by a discussion of such topics as 1. Radiography 2. Topography 3. Small-angle scattering 3.1. The differential cross section 3.2. Comparison of X-ray and neutron small-angle scattering 3.3. Examples of small-angle scattering. (orig.) [de

  14. Small Angle Neutron Scattering (SANS) characterization of electrically conducting polyaniline nanofiber/polyimide nanocomposites

    International Nuclear Information System (INIS)

    Hopkins, Alan R.; Tomczak, Sandra J.; Vij, Vandana; Jackson, Andrew J.

    2011-01-01

    Nanocomposites of polyaniline nanofibers and polyimide were fabricated and studied using small angle neutron scattering (SANS). The immiscible nature of the conformationally dissimilar polyaniline nanofiber and polyimide host is established by a series of experiments involving neutron scattering. Based on these techniques, we conclude that the crystal structure of the polyimides is not disrupted, and that there is no mixing between the two components on a molecular level. The morphology of the conducting salt component was analyzed by SANS data and was treated by two common models: Debye–Bueche (D–B) and inverse power law (IPL). Due to deviations in the linear curve fitting over a large scattering range, neither the D-B nor the IPL model could be used to characterize the size and shape of all PANI-0.5-CSA (polyaniline camphor sulfonic acid doped polymer)/polyimide blend systems. At 1 and 2% concentration, the D–B model suggested salt domains between 20 and 70 Å with fractal geometries implied by the IPL model. As salt concentrations increased to 5%, the structures were observed to change, but there is no simple structural model that provides a suitable basis for comparison.

  15. Recent developments in X-ray and neutron small-angle scattering instrumentation and data analysis

    International Nuclear Information System (INIS)

    Schelten, J.

    1978-01-01

    The developments in instrumentation and data analysis that have occurred in the field of small-angle X-ray and neutron scattering since 1973 are reviewed. For X-rays, the cone camera collimation was invented, synchrotrons and storage rings were demonstrated to be intense sources of X-radiation, and one- and two-dimensional position-sensitive detectors were interfaced to cameras with both point and line collimation. For neutrons, the collimators and detectors on the Juelich and Grenoble machines were improved, new D11-type instruments were built or are under construction at several sites, double-crystal instruments were set up, and various new machines have been proposed. Significant progress in data analysis and evaluation has been made through application of mathematical techniques such as the use of spline functions, error minimization with constraints, and linear programming. Several special experiments, unusual in respect to the anisotropy of the scattering pattern, gravitational effects, moving scatterers, and dynamic fast time slicing, are discussed. (Auth.)

  16. Small Angle Neutron Scattering (SANS) characterization of electrically conducting polyaniline nanofiber/polyimide nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, Alan R., E-mail: alan.r.hopkins@aero.org [Aerospace Corporation, Space Materials Lab, Micro/Nano Technology Dept, Polymers Section, M2/242, Los Angeles, CA 90009-2957 (United States); Tomczak, Sandra J. [AFRL/RZSM Materials Application Branch, Space and Missile Propulsion Division 10 East Saturn Blvd., Bldg. 8451, Edwards Air Force Base, CA 93524 (United States); Vij, Vandana [ERC. Inc., AFRL/PRSM, Edwards AFB, CA (United States); Jackson, Andrew J. [National Institute of Standards and Technology (NIST) Center for Neutron Research, 100 Bureau Drive, Stop 6102, Gaithersburg, MD 20899-6102 (United States)

    2011-12-30

    Nanocomposites of polyaniline nanofibers and polyimide were fabricated and studied using small angle neutron scattering (SANS). The immiscible nature of the conformationally dissimilar polyaniline nanofiber and polyimide host is established by a series of experiments involving neutron scattering. Based on these techniques, we conclude that the crystal structure of the polyimides is not disrupted, and that there is no mixing between the two components on a molecular level. The morphology of the conducting salt component was analyzed by SANS data and was treated by two common models: Debye-Bueche (D-B) and inverse power law (IPL). Due to deviations in the linear curve fitting over a large scattering range, neither the D-B nor the IPL model could be used to characterize the size and shape of all PANI-0.5-CSA (polyaniline camphor sulfonic acid doped polymer)/polyimide blend systems. At 1 and 2% concentration, the D-B model suggested salt domains between 20 and 70 A with fractal geometries implied by the IPL model. As salt concentrations increased to 5%, the structures were observed to change, but there is no simple structural model that provides a suitable basis for comparison.

  17. Frozen concentration fluctuations in a poly(N-isopropyl acrylamide) gel studied by neutron spin echo and small-angle neutron scattering

    CERN Document Server

    Koizumi, S; Richter, D; Schwahn, D; Faragó, B; Annaka, M

    2002-01-01

    By employing neutron spin echo and small-angle neutron scattering, we determined the structure factor of the frozen concentration fluctuations on nano-length scales in a swollen poly(N-isopropyl acrylamide) gel. The frozen contribution, showing a plateau at the low scattering wavenumber q (0.02 A sup - sup 1), is intimately related to the abnormal butterfly scattering pattern appearing at low q under deformation. (orig.)

  18. Insights into the interactions among Surfactin, betaines, and PAM: surface tension, small-angle neutron scattering, and small-angle X-ray scattering study.

    Science.gov (United States)

    Xiao, Jingwen; Liu, Fang; Garamus, Vasil M; Almásy, László; Handge, Ulrich A; Willumeit, Regine; Mu, Bozhong; Zou, Aihua

    2014-04-01

    The interactions among neutral polymer polyacrylamide (PAM) and the biosurfactant Surfactin and four betaines, N-dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (SDDAB), N-tetradecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (STDAB), N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (SHDAB), and N-dodecyl-N,N-dimethyl-2-ammonio-acetate (C12BE), in phosphate buffer solution (PBS) have been studied by surface tension measurements, small-angle neutron scattering (SANS), small-angle X-ray scattering (SAXS), and rheological experiments. It has been confirmed that the length of alkyl chain is a key parameter of interaction between betaines and PAM. Differences in scattering contrast between X-ray and neutrons for surfactants and PAM molecules provide the opportunity to separately follow the changes of structure of PAM and surfactant aggregates. At concentrations of betaines higher than CMC (critical micelle concentration) and C2 (CMC of surfactant with the presence of polymer), spherical micelles are formed in betaines and betaines/PAM solutions. Transition from spherical to rod-like aggregates (micelles) has been observed in solutions of Surfactin and Surfactin/SDDAB (αSurfactin = 0.67 (molar fraction)) with addition of 0.8 wt % of PAM. The conformation change of PAM molecules only can be observed for Surfactin/SDDAB/PAM system. Viscosity values follow the structural changes suggested from scattering measurements i.e., gradually increases for mixtures PAM → Surfactin/PAM → Surfactin/SDDAB/PAM in PBS.

  19. Direct observation of hydrogen trapped by NbC in steel using small-angle neutron scattering

    International Nuclear Information System (INIS)

    Ohnuma, Masato; Suzuki, Jun-ichi; Wei, Fu-Gao; Tsuzaki, Kaneaki

    2008-01-01

    Small-angle neutron scattering has been measured for 97.62Fe-0.23C-0.25Nb-1.90Ni (at.%) steel with and without hydrogen charging. The intensity of the scattering from nanosized NbC is higher for samples with hydrogen than for those without hydrogen. The enhanced scattering intensity for samples with hydrogen disappears after hydrogen desorption heat treatment. This result provides direct structural evidence for the trapping of hydrogen by NbC

  20. Small-angle neutron scattering study of micropore collapse in amorphous solid water.

    Science.gov (United States)

    Mitterdorfer, Christian; Bauer, Marion; Youngs, Tristan G A; Bowron, Daniel T; Hill, Catherine R; Fraser, Helen J; Finney, John L; Loerting, Thomas

    2014-08-14

    Vapor-deposited amorphous solid water (ASW) is the most abundant solid molecular material in space, where it plays a direct role in both the formation of more complex chemical species and the aggregation of icy materials in the earliest stages of planet formation. Nevertheless, some of its low temperature physics such as the collapse of the micropore network upon heating are still far from being understood. Here we characterize the nature of the micropores and their collapse using neutron scattering of gram-quantities of D2O-ASW of internal surface areas up to 230 ± 10 m(2) g(-1) prepared at 77 K. The model-free interpretation of the small-angle scattering data suggests micropores, which remain stable up to 120-140 K and then experience a sudden collapse. The exact onset temperature to pore collapse depends on the type of flow conditions employed in the preparation of ASW and, thus, the specific surface area of the initial deposit, whereas the onset of crystallization to cubic ice is unaffected by the flow conditions. Analysis of the small-angle neutron scattering signal using the Guinier-Porod model suggests that a sudden transition from three-dimensional cylindrical pores with 15 Å radius of gyration to two-dimensional lamellae is the mechanism underlying the pore collapse. The rather high temperature of about 120-140 K of micropore collapse and the 3D-to-2D type of the transition unraveled in this study have implications for our understanding of the processing and evolution of ices in various astrophysical environments.

  1. Joint small-angle X-ray and neutron scattering data analysis of asymmetric lipid vesicles.

    Science.gov (United States)

    Eicher, Barbara; Heberle, Frederick A; Marquardt, Drew; Rechberger, Gerald N; Katsaras, John; Pabst, Georg

    2017-04-01

    Low- and high-resolution models describing the internal transbilayer structure of asymmetric lipid vesicles have been developed. These models can be used for the joint analysis of small-angle neutron and X-ray scattering data. The models describe the underlying scattering length density/electron density profiles either in terms of slabs or through the so-called scattering density profile, previously applied to symmetric lipid vesicles. Both models yield structural details of asymmetric membranes, such as the individual area per lipid, and the hydrocarbon thickness of the inner and outer bilayer leaflets. The scattering density profile model, however, comes at a cost of increased computational effort but results in greater structural resolution, showing a slightly lower packing of lipids in the outer bilayer leaflet of ∼120 nm diameter palmitoyl-oleoyl phosphatidyl-choline (POPC) vesicles, compared to the inner leaflet. Analysis of asymmetric dipalmitoyl phosphatidylcholine/POPC vesicles did not reveal evidence of transbilayer coupling between the inner and outer leaflets at 323 K, i.e. above the melting transition temperature of the two lipids.

  2. Study of α-crystallin structure by small-angle neutron scattering with contrast variation

    International Nuclear Information System (INIS)

    Krivandin, A.V.; Muranov, K.O.; Polyanskij, N.B.; Ostrovskij, M.A.; Murugova, T.N.; Kuklin, A.I.; Aksenov, V.L.

    2010-01-01

    The structure of the oligomeric protein α-crystallin from the bovine eye lens has been investigated by small-angle neutron scattering (SANS) by the contrast variation method (volume fraction of D 2 O was 0, 23, 68 and 90%). Experiments were carried out on YuMO spectrometer (IBR-2 reactor, JINR). From the SANS curves the match point for α-crystallin (43% D 2 O) and its average scattering length density at this point (2.4·10 10 cm -2 ) have been obtained. The radius of gyration and distance distribution functions for α-crystallin have been calculated as well. On the basis of these calculations it was concluded that α-crystallin has a homogeneous distribution of the scattering density in domains inaccessible for water penetration and all parts of this protein undergo a uniform deuteration. The latter indicates that all α-crystallin subunits have an equal accessibility for water and presumably for some other low molecular weight substances. These conclusions on the α-crystallin structure (a homogeneous distribution of the scattering density and an equal accessibility of all subunits for low molecular weight substances) should be taken into account in the time of elaboration of α-crystallin quaternary structure models

  3. Initial characterization of mudstone nanoporosity with small angle neutron scattering using caprocks from carbon sequestration sites

    International Nuclear Information System (INIS)

    McCray, John; Navarre-Sitchler, Alexis; Mouzakis, Katherine; Heath, Jason E.; Dewers, Thomas A.; Rother, Gernot

    2010-01-01

    Geological carbon sequestration relies on the principle that CO 2 injected deep into the subsurface is unable to leak to the atmosphere. Structural trapping by a relatively impermeable caprock (often mudstone such as a shale) is the main trapping mechanism that is currently relied on for the first hundreds of years. Many of the pores of the caprock are of micrometer to nanometer scale. However, the distribution, geometry and volume of porosity at these scales are poorly characterized. Differences in pore shape and size can cause variation in capillary properties and fluid transport resulting in fluid pathways with different capillary entry pressures in the same sample. Prediction of pore network properties for distinct geologic environments would result in significant advancement in our ability to model subsurface fluid flow. Specifically, prediction of fluid flow through caprocks of geologic CO 2 sequestration reservoirs is a critical step in evaluating the risk of leakage to overlying aquifers. The micro- and nanoporosity was analyzed in four mudstones using small angle neutron scattering (SANS). These mudstones are caprocks of formations that are currently under study or being used for carbon sequestration projects and include the Marine Tuscaloosa Group, the Lower Tuscaloosa Group, the upper and lower shale members of the Kirtland Formation, and the Pennsylvanian Gothic shale. Total organic carbon varies from <0.3% to 4% by weight. Expandable clay contents range from 10% to ∼40% in the Gothic shale and Kirtland Formation, respectively. Neutrons effectively scatter from interfaces between materials with differing scattering length density (i.e. minerals and pores). The intensity of scattered neutrons, I(Q), where Q is the scattering vector, gives information about the volume of pores and their arrangement in the sample. The slope of the scattering data when plotted as log I(Q) vs. log Q provides information about the fractality or geometry of the pore network

  4. Initial characterization of mudstone nanoporosity with small angle neutron scattering using caprocks from carbon sequestration sites.

    Energy Technology Data Exchange (ETDEWEB)

    McCray, John (Colorado School of Mines); Navarre-Sitchler, Alexis (Colorado School of Mines); Mouzakis, Katherine (Colorado School of Mines); Heath, Jason E.; Dewers, Thomas A.; Rother, Gernot (Oak Ridge National Laboratory)

    2010-11-01

    Geological carbon sequestration relies on the principle that CO{sub 2} injected deep into the subsurface is unable to leak to the atmosphere. Structural trapping by a relatively impermeable caprock (often mudstone such as a shale) is the main trapping mechanism that is currently relied on for the first hundreds of years. Many of the pores of the caprock are of micrometer to nanometer scale. However, the distribution, geometry and volume of porosity at these scales are poorly characterized. Differences in pore shape and size can cause variation in capillary properties and fluid transport resulting in fluid pathways with different capillary entry pressures in the same sample. Prediction of pore network properties for distinct geologic environments would result in significant advancement in our ability to model subsurface fluid flow. Specifically, prediction of fluid flow through caprocks of geologic CO{sub 2} sequestration reservoirs is a critical step in evaluating the risk of leakage to overlying aquifers. The micro- and nanoporosity was analyzed in four mudstones using small angle neutron scattering (SANS). These mudstones are caprocks of formations that are currently under study or being used for carbon sequestration projects and include the Marine Tuscaloosa Group, the Lower Tuscaloosa Group, the upper and lower shale members of the Kirtland Formation, and the Pennsylvanian Gothic shale. Total organic carbon varies from <0.3% to 4% by weight. Expandable clay contents range from 10% to {approx}40% in the Gothic shale and Kirtland Formation, respectively. Neutrons effectively scatter from interfaces between materials with differing scattering length density (i.e. minerals and pores). The intensity of scattered neutrons, I(Q), where Q is the scattering vector, gives information about the volume of pores and their arrangement in the sample. The slope of the scattering data when plotted as log I(Q) vs. log Q provides information about the fractality or geometry of

  5. Neutron scattering. Experiment manuals

    International Nuclear Information System (INIS)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner

    2014-01-01

    The following topics are dealt with: The thermal triple-axis spectrometer PUMA, the high-resolution powder diffractometer SPODI, the hot-single-crystal diffractometer HEiDi, the three-axis spectrometer PANDA, the backscattering spectrometer SPHERES, the DNS neutron-polarization analysis, the neutron spin-echo spectrometer J-NSE, small-angle neutron scattering at KWS-1 and KWS-2, a very-small-angle neutron scattering diffractometer with focusing mirror, the reflectometer TREFF, the time-of-flight spectrometer TOFTOF. (HSI)

  6. Neutron scattering. Experiment manuals

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2014-07-01

    The following topics are dealt with: The thermal triple-axis spectrometer PUMA, the high-resolution powder diffractometer SPODI, the hot-single-crystal diffractometer HEiDi, the three-axis spectrometer PANDA, the backscattering spectrometer SPHERES, the DNS neutron-polarization analysis, the neutron spin-echo spectrometer J-NSE, small-angle neutron scattering at KWS-1 and KWS-2, a very-small-angle neutron scattering diffractometer with focusing mirror, the reflectometer TREFF, the time-of-flight spectrometer TOFTOF. (HSI)

  7. Small-angle neutron scattering correlation functions of bulk magnetic materials.

    Science.gov (United States)

    Mettus, Denis; Michels, Andreas

    2015-10-01

    On the basis of the continuum theory of micromagnetics, the correlation function of the spin-misalignment small-angle neutron scattering cross section of bulk ferromagnets ( e.g. elemental polycrystalline ferromagnets, soft and hard magnetic nanocomposites, nanoporous ferromagnets, or magnetic steels) is computed. For such materials, the spin disorder which is related to spatial variations in the saturation magnetization and magnetic anisotropy field results in strong spin-misalignment scattering dΣ M /dΩ along the forward direction. When the applied magnetic field is perpendicular to the incoming neutron beam, the characteristics of dΣ M /dΩ ( e.g. the angular anisotropy on a two-dimensional detector or the asymptotic power-law exponent) are determined by the ratio of magnetic anisotropy field strength H p to the jump Δ M in the saturation magnetization at internal interfaces. Here, the corresponding one- and two-dimensional real-space correlations are analyzed as a function of applied magnetic field, the ratio H p /Δ M , the single-particle form factor and the particle volume fraction. Finally, the theoretical results for the correlation function are compared with experimental data on nanocrystalline cobalt and nickel.

  8. Investigation of digestion Kinetics in commercial starches using in-situ small-angle neutron scattering

    International Nuclear Information System (INIS)

    Blazek, Jaroslav; Gilbert, Elliot Paul

    2009-01-01

    Full text: The digestion of starch has been the subject of many investigations, mostly involving in vitro measurement of the susceptibility of starches to attack by different enzymes, rather than measuring actual digestibility in vivo. The rate and extent of amylolytic hydrolysis of granular starches is known to vary according to botanical origin. Granule characteristics considered to influence susceptibility to attack by alpha-amylase include crystallinity, granule size and available specific surface, amylose content, porosity, structural inhomogeneities and degree of integrity. Most in-vitro studies of granular starch digestion have been limited to samples for which aliquots have been removed from the reaction mixture at various time intervals and freeze-dried to be subsequently characterized using a range of techniques. It remains unclear whether sample preparation creates artefacts in the samples. In this study, we have studied the kinetics of starch digestion of several commercial granular starches by time-resolved small-angle neutron scattering using an in-situ digestion chamber allowing, for the first time, to follow structural changes of starch in the course of digestion directly in the digestion mixture. Additionally, samples before and after digestion were studied by x-ray diffraction, small-angle x-ray scattering, differential scanning calorimetry and microscopy. Microscopy revealed that studied starches, which varied in their amylose content and digestion kinetics, followed different modes of attack The multidisciplinary approach allowed the nanostructural changes detected by small-angle scattering in the course of enzymic breakdown to be correlated with changes in crystallinity and functional properties.

  9. A new small-angle neutron scattering spectrometer at China Mianyang research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Mei, E-mail: pm740509@163.com; Sun, Liangwei; Chen, Liang; Sun, Guangai; Chen, Bo; Xie, Chaomei; Xia, Qingzhong; Yan, Guanyun; Tian, Qiang; Huang, Chaoqiang; Pang, Beibei; Zhang, Ying; Wang, Yun; Liu, Yaoguang; Kang, Wu; Gong, Jian

    2016-02-21

    A new pinhole small-angle neutron scattering (SANS) spectrometer, installed at the cold neutron source of the 20 MW China Mianyang Research Reactor (CMRR) in the Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, has been put into use since 2014. The spectrometer is equipped with a multi-blade mechanical velocity selector, a multi-beam collimation system, and a two-dimensional He-3 position sensitive neutron detector. The q-range of the spectrometer covers from 0.01 nm{sup −1} to 5.0 nm{sup −1}. In this paper, the design and characteristics of the SANS spectrometer are described. The q-resolution calculations, together with calibration measurements of silver behenate and a dispersion of nearly monodisperse poly-methyl-methacrylate nanoparticles indicate that our SANS spectrometer has a good performance and is now in routine service. - Highlights: • A new SANS spectrometer has been put into use since 2014 in China. • One MBR selector possesses a higher resolution compared with traditional selector is used. • The spectrometer has a good performance and is now in routinely service.

  10. Design and Construction of the Control System for Batan Small Angle Neutron Scattering Spectrometer (SMARter

    Directory of Open Access Journals (Sweden)

    E. Santoso

    2008-07-01

    Full Text Available A 36 m Small Angle Neutron Scattering (SANS Spectrometer (SMARTer has been installed in Serpong, Indonesia in 1992. As time goes by, the original main computer was out of order and the instrument had not been operated since 2003. In order to activate the SMARTer, in the year 2005, a work on designing and constructing a new control system for SMARTer was carried out. The main component of this control system is a programmable peripheral I/O (IC PPI 8255 and was assembled as a plug-in board at an ISA slot of a personal computer. An IC PPI 8255 was programmed to control the mechanical movements of the instrument’s components: four neutron guide tubes, six pinholes collimator, a detector and a beam stopper. The test either with or without neutron beam has shown that this control system can be implemented for the mechanical movements of SMARTer. Error of moving the detector in the distance range of 1.5 m – 18 m is only 1 mm and the other movements have no error at all (precise.

  11. A new small-angle neutron scattering spectrometer at China Mianyang research reactor

    International Nuclear Information System (INIS)

    Peng, Mei; Sun, Liangwei; Chen, Liang; Sun, Guangai; Chen, Bo; Xie, Chaomei; Xia, Qingzhong; Yan, Guanyun; Tian, Qiang; Huang, Chaoqiang; Pang, Beibei; Zhang, Ying; Wang, Yun; Liu, Yaoguang; Kang, Wu; Gong, Jian

    2016-01-01

    A new pinhole small-angle neutron scattering (SANS) spectrometer, installed at the cold neutron source of the 20 MW China Mianyang Research Reactor (CMRR) in the Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, has been put into use since 2014. The spectrometer is equipped with a multi-blade mechanical velocity selector, a multi-beam collimation system, and a two-dimensional He-3 position sensitive neutron detector. The q-range of the spectrometer covers from 0.01 nm −1 to 5.0 nm −1 . In this paper, the design and characteristics of the SANS spectrometer are described. The q-resolution calculations, together with calibration measurements of silver behenate and a dispersion of nearly monodisperse poly-methyl-methacrylate nanoparticles indicate that our SANS spectrometer has a good performance and is now in routine service. - Highlights: • A new SANS spectrometer has been put into use since 2014 in China. • One MBR selector possesses a higher resolution compared with traditional selector is used. • The spectrometer has a good performance and is now in routinely service.

  12. Probing the conformation of FhaC with small-angle neutron scattering and molecular modeling.

    Science.gov (United States)

    Gabel, Frank; Lensink, Marc F; Clantin, Bernard; Jacob-Dubuisson, Françoise; Villeret, Vincent; Ebel, Christine

    2014-07-01

    Probing the solution structure of membrane proteins represents a formidable challenge, particularly when using small-angle scattering. Detergent molecules often present residual scattering contributions even at their match point in small-angle neutron scattering (SANS) measurements. Here, we studied the conformation of FhaC, the outer-membrane, β-barrel transporter of the Bordetella pertussis filamentous hemagglutinin adhesin. SANS measurements were performed on homogeneous solutions of FhaC solubilized in n-octyl-d17-βD-glucoside and on a variant devoid of the α helix H1, which critically obstructs the FhaC pore, in two solvent conditions corresponding to the match points of the protein and the detergent, respectively. Protein-bound detergent amounted to 142 ± 10 mol/mol as determined by analytical ultracentrifugation. By using molecular modeling and starting from three distinct conformations of FhaC and its variant embedded in lipid bilayers, we generated ensembles of protein-detergent arrangement models with 120-160 detergent molecules. The scattered curves were back-calculated for each model and compared with experimental data. Good fits were obtained for relatively compact, connected detergent belts, which occasionally displayed small detergent-free patches on the outer surface of the β barrel. The combination of SANS and modeling clearly enabled us to infer the solution structure of FhaC, with H1 inside the pore as in the crystal structure. We believe that our strategy of combining explicit atomic detergent modeling with SANS measurements has significant potential for structural studies of other detergent-solubilized membrane proteins. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  13. Three-dimensional magnetic spin-echo small-angle neutron scattering and neutron depolarization: A comparison

    International Nuclear Information System (INIS)

    Rekveldt, M. Theo; Dijk, Niels H. van; Grigoriev, Serguei V.; Kraan, Wicher H.; Bouwman, Wim G.

    2006-01-01

    The recently developed magnetic spin-echo small-angle neutron scattering (SANS) technique provides unique information about the distance correlation of the local vector magnetization as a function of the spin-echo length within a magnetic material. The technique probes the magnetic correlations on a length scale from 10 nm up to 10 μm within the bulk of a magnetic material by evaluating the Larmor precession of a polarized neutron beam in a spin-echo setup. The characteristics of the spin-echo SANS technique are discussed and compared to those of the more conventional neutron depolarization technique. Both of these techniques probe the average size of the magnetic inhomogeneities and the local magnetic texture. The magnetic spin-echo SANS technique gives information on the size distribution of these magnetic inhomogeneities perpendicular to the beam and, in principle, independent on the local magnetic induction. This information is not accessible by the neutron depolarization technique that gives the average size parallel to the beam multiplied with the square of the local magnetic induction. The basic possibilities of the magnetic spin-echo SANS technique are demonstrated by experiments on samples with a strong magnetic texture

  14. Primary Data Treatment Software for Position-Sensitive Detector of Small-Angle Neutron Scattering Spectrometer in the Isotropic Pattern Scattering Case

    Science.gov (United States)

    Soloviev, Alexei; Kutuzov, Sergei; Ivankov, Olexander; Kuklin, Alexander

    2018-02-01

    A new data converter has been created for the new position-sensitive detector (PSD) of small-angle neutron scattering (SANS) spectrometer YuMO. In the isotropic pattern scattering case, it provides the possibility for processing PSD data with the SAS data processing program that has already been in use.

  15. Primary Data Treatment Software for Position-Sensitive Detector of Small-Angle Neutron Scattering Spectrometer in the Isotropic Pattern Scattering Case

    Directory of Open Access Journals (Sweden)

    Soloviev Alexei

    2018-01-01

    Full Text Available A new data converter has been created for the new position-sensitive detector (PSD of small-angle neutron scattering (SANS spectrometer YuMO. In the isotropic pattern scattering case, it provides the possibility for processing PSD data with the SAS data processing program that has already been in use.

  16. Poly(NIPAM) micro gel particle de-swelling: a light scattering and small-angle neutron scattering study

    International Nuclear Information System (INIS)

    Daly, E.; Saunders, B.

    1999-01-01

    Full text: Small-angle neutron scattering (SANS) has been used to investigate structural changes during the de-swelling of poly(N-isopropylacrylamide) [poly(NIPAM)] micro gel particles induced by temperature variation and the addition of free polymer [poly(ethylene oxide)]. The extent of particle de-swelling was characterized by photon correlation spectroscopy (PCS). Thermally-induced de-swelling of poly(NIPAM) / deuterated water dispersions occurred on increasing the temperature in the region of the lower critical solution temperature (LCST). The latter was found to be 34 deg C, which is 2 deg C higher than the value reported for poly(NIPAM) particles dispersed in water. The SANS data exhibit a Porod form (Q -4 ) of scattering in regard to the size of the colloidal particles. However, in the swollen state, the scattering measured at temperatures less than the LCST, also has a contribution from poly(NIPAM) chains in a solution-like environment (Ornstein-Zernicke scattering). The SANS data confirm earlier PCS measurements showing that addition of free polymer induces particle de-swelling. The SANS data obtained using added free polymer are the first examples of their type to be reported

  17. Small-Angle Neutron Scattering for Structural Biology of Protein-RNA Complexes.

    Science.gov (United States)

    Gabel, Frank

    2015-01-01

    This chapter deals with the applications of small-angle neutron scattering (SANS) for the structural study of protein-RNA complexes in solution. After a brief historical introduction, the basic theory and practical requirements (e.g., sample state) for SANS experiments will be treated. Next, model-free parameters, such as the molecular mass and the radius of gyration, which can be obtained without a priori structural information, will be introduced. A more detailed section on the specific properties of SANS (with respect to its sister technique, small-angle X-ray scattering), and their implications on possibilities and limits of model building and interpretation will be discussed with a focus on protein-RNA systems. A practical illustration of the information content of SANS data will be given by applying ab initio modeling to a tRNA-synthetase system of known high-resolution structure. Finally, two present state-of-the-art examples that combine SANS data with complementary structural biology techniques (NMR and crystallography) will be presented and possible future developments and applications will be discussed. © 2015 Elsevier Inc. All rights reserved.

  18. Tandem analyzer crystals system doubles counting rate for Bonse Hart ultra-small-angle neutron-scattering spectrometer

    Science.gov (United States)

    Yamaguchi, Daisuke; Koizumi, Satoshi; Motokawa, Ryuhei; Kumada, Takayuki; Aizawa, Kazuya; Hashimoto, Takeji

    2006-11-01

    A new tandem analyzer crystals system was introduced on Bonse-Hart ultra-small-angle neutron-scattering spectrometer at research reactor JRR-3, Tokai, Japan. Conventional Bonse-Hart setup consumes a considerable time to measure a scattering profile of whole q range (2×10 -4 nm -1neutrons from the sample and having different q are measured step by step. To overcome this difficulty two analyzer channel-cut silicon perfect crystals were settled in tandem and each of them diffracted the scattering of different q. In consequence, a simultaneous detection at two different q positions was realized and the measurement time was reduced to half.

  19. Small-angle neutron scattering in a high-temperature furnace

    International Nuclear Information System (INIS)

    Long, G.G.; Krueger, S.; Allen, A.J.; Burdette, H.; Kerch, H.M.

    1995-01-01

    Small-angle neutron scattering (SANS) is increasingly used to obtain statistically-representative data on particle or pore sizes, number and volume fractions, morphology and total surface areas in technological materials. Until recently, however, it had not been possible to perform in-situ microstructural investigations during thermal treatment. This paper reports on a new high-temperature (up to 1,700 C) SANS furnace for materials research. Two interchangeable inner furnaces were built for a single outer atmosphere chamber so that either an oxidizing, a reducing, or a neutral environment can be used. Results derived during sintering of a controlled-porosity silica gel will be presented. The new furnace has made it possible for the first time to measure total porous surface areas and the evolution of pore sizes in situ during densification without interruption. Such measurements are expected to lead to improved process models offering quantitative predictability of product microstructures from the processing history of real materials

  20. Size analysis of nanometer titanium carbide in steel by using small-angle neutron scattering

    International Nuclear Information System (INIS)

    Yasuhara, Hisao; Sato, Kaoru; Toji, Yuki; Ohnuma, Masato; Suzuki, Jun-ichi; Tomota, Yo

    2010-01-01

    Utilization of nanometer size precipitates in steel is a promising technology for the developing high tensile strength steels, and it is important to analyze the size of the precipitates. Electron microscopy is a powerful method in directly determining the precipitates size, but the area observed is limited and statistical procedure is tedious. Therefore, size analysis of precipitates in steel was conducted by using small-angle neutron scattering method (SANS). Sample (0.045%C-1.8%Mn-0.2%Ti-0.004%N) with different heat treatment was used for the experiments. Size of nanometer size TiC calculated by SANS profiles agreed with that obtained by direct observation of precipitates by transmission electron microscope (TEM). We have succeeded in macroscopic and non-destructive determination of the size of nanometer-sized TiC. (author)

  1. A Small Angle Neutron Scattering Study of Cylindrical nanoparticle with Controlled Surface Charge Density

    International Nuclear Information System (INIS)

    Kim, Tae-Hwan; Choi, Sung-Min; Kline, Steven R.

    2007-01-01

    Surfactant molecules in aqueous solution self assemble into various micellar structures such as sphere, rod, vesicle, and lamellar, above critical micelle concentration (CMC). Self-assembled surfactants systems, therefore, have been very popular as templates for preparing various nanostructured materials. Due to their dynamic nature, however, micellar structures are very susceptible to solution conditions such as temperature, concentration, pH and pressure, limiting their applications. In this study, we have developed rigid rod-like nanoparticles with controlled surface charge density by the free radical polymerization of cationic surfactants with polymerizable counterions, cetyltrimethylammonium 4- vinylbenzoate (CTVB), with varying concentration of sodium styrenesulfonate (NaSS). The structure and surface charge density of the nanoparticles were characterized by small angle neutron scattering (SANS) and zeta potential measurements

  2. Small angle neutron scattering study of martensitic/ferritic ODS alloys

    International Nuclear Information System (INIS)

    Mathon, M.H.; Perrut, M.; Zhong, S.Y.; Carlan, Y. de

    2012-01-01

    Small Angle Neutron Scattering (SANS) is a key tool in material study at the nanoscale. This method allows characterization, in a non-destructive way, of small particles (precipitates, cavities, etc.) ranging in size between 1 and 100 nm. This technique, giving statistical data representative of the whole sample, is particularly adapted to the study of steels. We will present an overview of the SANS possibilities applied to the ODS ferritic/martensitic steels. The main objective is to study the evolution of the oxide dispersion during the different stages of the fabrication, that is, after mechanical alloying, consolidation process (extrusion or HIP) and after thermal treatments. The treatments of SANS data obtained on different ODS Fe9–14%Cr alloys are detailed by discussing the strengths and limitations of the technique. Various Fe–Cr–W–Ti experimental alloys have been characterized.

  3. Small angle neutron scattering study of martensitic/ferritic ODS alloys

    Energy Technology Data Exchange (ETDEWEB)

    Mathon, M.H., E-mail: mhmathon@cea.fr [Laboratoire Leon Brillouin, CEA-CNRS, CEA/Saclay, 91191 Gif-sur-Yvette (France); Perrut, M., E-mail: mikael.perrut@onera.fr [DMSM, ONERA, 29 Avenue de la Division Leclerc, F-92322 Chatillon (France); Zhong, S.Y., E-mail: shengyi.zhong@cea.fr [Laboratoire Leon Brillouin, CEA-CNRS, CEA/Saclay, 91191 Gif-sur-Yvette (France); Carlan, Y. de, E-mail: yann.decarlan@cea.fr [Nuclear Materials Department, CEA/Saclay, 91191 Gif-sur-Yvette (France)

    2012-09-15

    Small Angle Neutron Scattering (SANS) is a key tool in material study at the nanoscale. This method allows characterization, in a non-destructive way, of small particles (precipitates, cavities, etc.) ranging in size between 1 and 100 nm. This technique, giving statistical data representative of the whole sample, is particularly adapted to the study of steels. We will present an overview of the SANS possibilities applied to the ODS ferritic/martensitic steels. The main objective is to study the evolution of the oxide dispersion during the different stages of the fabrication, that is, after mechanical alloying, consolidation process (extrusion or HIP) and after thermal treatments. The treatments of SANS data obtained on different ODS Fe9-14%Cr alloys are detailed by discussing the strengths and limitations of the technique. Various Fe-Cr-W-Ti experimental alloys have been characterized.

  4. Small-angle neutron scattering investigation of Pt-loaded electrodes for polymer electrolyte fuel cells

    International Nuclear Information System (INIS)

    Coppola, R.; Giorgi, L.; Lapp, A.

    1999-01-01

    Complete text of publication follows. Pt-loaded carbon catalysts are being developed for polymer electrolyte fuel cell technology. They are prepared by depositing, with different techniques, an electrocatalytic layer containing dispersed Pt clusters on a composite carbon substrate. The performance and the lifetime of these catalysts are strongly correlated to the deposition technique, to the Pt content and to the size distribution function of the Pt clusters. Small-angle neutron scattering (SANS) measurements have been carried out on catalysts with relatively high Pt deposited content (.5 mg cm -2 ). A Pt-free C-paper support (identical to the one used for the platinized samples) has been used as a reference to obtain the SANS signal arising from the Pt clusters. Their size distribution function has been determined and compared with the results of transmission electron microscopy (TEM) observations. (author)

  5. A small-angle neutron scattering investigation of coke deposits on catalysts

    International Nuclear Information System (INIS)

    Acharya, D.R.; Hughes, R.; Allen, A.J.

    1990-01-01

    Small-angle neutron scattering (SANS) has been used to characterize a silica-alumina catalyst before and after coke deposition. The reaction used to deactivate the catalyst was the isomerization of xylenes. The results showed that, while most of the surface area in this type of catalyst resides in the ultrafine pores of diameters less than 1 nm occupying about 7% of the sample volume, there appears to be no coke deposition in these pores. The coke seems to coat the solid structures of 3.3-nm diameter which are of capillary shape. Such structures occupy about 6% of the sample volume. The coke was found to correspond to amonolayer of composition CH 0.3 with a density of 1660 kg/m 3

  6. Characterisation of creep cavitation damage in a stainless steel pressure vessel using small angle neutron scattering

    CERN Document Server

    Bouchard, P J; Treimer, W

    2002-01-01

    Grain-boundary cavitation is the dominant failure mode associated with initiation of reheat cracking, which has been widely observed in austenitic stainless steel pressure vessels operating at temperatures within the creep range (>450 C). Small angle neutron scattering (SANS) experiments at the LLB PAXE instrument (Saclay) and the V12 double-crystal diffractometer of the HMI-BENSC facility (Berlin) are used to characterise cavitation damage (in the size range R=10-2000 nm) in a variety of creep specimens extracted from ex-service plant. Factors that affect the evolution of cavities and the cavity-size distribution are discussed. The results demonstrate that SANS techniques have the potential to quantify the development of creep damage in type-316H stainless steel, and thereby link microstructural damage with ductility-exhaustion models of reheat cracking. (orig.)

  7. Deciphering the "Fuzzy" Interaction of FG Nucleoporins and Transport Factors Using Small-Angle Neutron Scattering.

    Science.gov (United States)

    Sparks, Samuel; Temel, Deniz B; Rout, Michael P; Cowburn, David

    2018-03-06

    The largely intrinsically disordered phenylalanine-glycine-rich nucleoporins (FG Nups) underline a selectivity mechanism that enables the rapid translocation of transport factors (TFs) through the nuclear pore complexes (NPCs). Conflicting models of NPC transport have assumed that FG Nups undergo different conformational transitions upon interacting with TFs. To selectively characterize conformational changes in FG Nups induced by TFs we performed small-angle neutron scattering (SANS) with contrast matching. Conformational-ensembles derived from SANS data indicated an increase in the overall size of FG Nups is associated with TF interaction. Moreover, the organization of the FG motif in the interacting state is consistent with prior experimental analyses defining that FG motifs undergo conformational restriction upon interacting with TFs. These results provide structural insights into a highly dynamic interaction and illustrate how functional disorder imparts rapid and selective FG Nup-TF interactions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Quantitative 3D determination of self-assembled structures on nanoparticles using small angle neutron scattering.

    Science.gov (United States)

    Luo, Zhi; Marson, Domenico; Ong, Quy K; Loiudice, Anna; Kohlbrecher, Joachim; Radulescu, Aurel; Krause-Heuer, Anwen; Darwish, Tamim; Balog, Sandor; Buonsanti, Raffaella; Svergun, Dmitri I; Posocco, Paola; Stellacci, Francesco

    2018-04-09

    The ligand shell (LS) determines a number of nanoparticles' properties. Nanoparticles' cores can be accurately characterized; yet the structure of the LS, when composed of mixture of molecules, can be described only qualitatively (e.g., patchy, Janus, and random). Here we show that quantitative description of the LS' morphology of monodisperse nanoparticles can be obtained using small-angle neutron scattering (SANS), measured at multiple contrasts, achieved by either ligand or solvent deuteration. Three-dimensional models of the nanoparticles' core and LS are generated using an ab initio reconstruction method. Characteristic length scales extracted from the models are compared with simulations. We also characterize the evolution of the LS upon thermal annealing, and investigate the LS morphology of mixed-ligand copper and silver nanoparticles as well as gold nanoparticles coated with ternary mixtures. Our results suggest that SANS combined with multiphase modeling is a versatile approach for the characterization of nanoparticles' LS.

  9. Small-Angle Neutron Scattering for Molecular Biology: Basics and Instrumentation

    Science.gov (United States)

    Heller, William T.; Littrell, Kenneth C.

    As researchers strive to understand the interplay between the complex molecular systems that make up living cells, tools for characterizing the interactions between the various players involved have developed. Small-angle neutron scattering (SANS) plays an important role in building a molecular-level understanding of the structures of macromolecular systems that make up cells. SANS is widely applicable to the study of biological structures including, but by no means limited to, protein-protein or protein-nucleic acid complexes, lipid membranes, cellular scaffolding, and amyloid plaques. Here, we present a brief description of the technique as it is commonly applied to the study of biological systems and an overview instrumentation that is available at the various facilities around the world.

  10. Cholesterol solubility limit in lipid membranes probed by small angle neutron scattering and MD simulations.

    Science.gov (United States)

    Garg, Sumit; Castro-Roman, Francisco; Porcar, Lionel; Butler, Paul; Bautista, Pedro Jesus; Krzyzanowski, Natalie; Perez-Salas, Ursula

    2014-12-14

    The solubility limits of cholesterol in small unilamellar vesicles made of POPS and POPC were probed using Small Angle Neutron Scattering (SANS) and coarse grained (CG) molecular dynamics (MD) simulations. SANS, being non-invasive, allowed the direct and quantitative measurement of cholesterol in intact vesicles. Our experimental measurements reveal a 61% mole fraction solubility limit of cholesterol in POPC, consistent with previous studies. However, in POPS the solubility limit of cholesterol is found to be 73% mole fraction. Previous work reports solubility limits of cholesterol in POPS varying significantly, ranging from 36% up to 66%. The CG MD simulations are in remarkable quantitative agreement with our experimental results showing similar solubility limits. Further, neither experiments nor simulations show evidence of stable nanodomains of cholesterol in POPS membranes as suggested in some previous reports.

  11. Search for small-angle neutron scattering in MnO at 1700K

    International Nuclear Information System (INIS)

    Routbort, J.L.; Epperson, J.E.; Klippert, T.E.; Goretta, K.C.

    1986-01-01

    A preliminary small-angle scattering (SANS) experiment has been performed on MnO single crystal at the Intense Pulsed Neutron Source. The experiment was preformed at 1700 0 K at oxygen partial pressures of 2.2 x 10 -4 , 1 x 10 2 , and 2 x 10 2 Pa, which resulted in deviations from stoichiometry of about 0.0015, 0.082, and 0.127. No statistically significant change in SANS was observed at this temperature with the pressure changes. Neither was any significant change observed in the wavelength-dependent sample transmission, also measured in-situ as a function of pressure. Therefore, either clustering of cation vacancies is negligible in MnO for these conditions, or the clusters are smaller than about 5 A. Of proposed cluster configurations, only the existence of the smallest (4:1, 6:2, or possible 8:3) appears to be consistent with these results

  12. Small angle neutron scattering and calorimetric studies of large unilamellar vesicles of the phospholipid dipalmitoylphosphatidylcholine

    Energy Technology Data Exchange (ETDEWEB)

    Mason, P.C.; Gaulin, B.D. [Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, L8S 4M1 (CANADA); Epand, R.M. [Department of Biochemistry, McMaster University, Hamilton, Ontario, L8N 3Z5 (CANADA); Wignall, G.D.; Lin, J.S. [Center for Small-Angle Scattering Research, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    1999-03-01

    High-resolution differential scanning calorimetry (DSC) and small angle neutron scattering (SANS) experiments have been conducted on large unilamellar vesicles (LUV{close_quote}s) of the phospholipid dipalmitoylphosphatidylcholine (DPPC) in excess water. The DSC results indicate a phase transition at temperatures corresponding to the gel (L{sub {beta}{sup {prime}}}) to ripple (P{sub {beta}{sup {prime}}}) phase transition seen in multilamellar vesicles of DPPC while the SANS experiments provide direct evidence for the formation of the P{sub {beta}{sup {prime}}} phase in these systems. In addition, it is shown that SANS is an effective technique for extracting structural parameters such as vesicle radius and thickness in LUV model membrane systems. {copyright} {ital 1999} {ital The American Physical Society}

  13. Preliminary analysis of the distribution of water in human hair by small-angle neutron scattering.

    Science.gov (United States)

    Kamath, Yash; Murthy, N Sanjeeva; Ramaprasad, Ram

    2014-01-01

    Diffusion and distribution of water in hair can reveal the internal structure of hair that determines the penetration of various products used to treat hair. The distribution of water into different morphological components in unmodified hair, cuticle-free hair, and hair saturated with oil at various levels of humidity was examined using small-angle neutron scattering (SANS) by substituting water with deuterium oxide (D(2)O). Infrared spectroscopy was used to follow hydrogen-deuterium exchange. Water present in hair gives basically two types of responses in SANS: (i) interference patterns, and (ii) central diffuse scattering (CDS) around the beam stop. The amount of water in the matrix between the intermediate filaments that gives rise to interference patterns remained essentially constant over the 50-98% humidity range without swelling this region of the fiber extensively. This observation suggests that a significant fraction of water in the hair, which contributes to the CDS, is likely located in a different morphological region of hair that is more like pores in a fibrous structure, which leads to significant additional swelling of the fiber. Comparison of the scattering of hair treated with oil shows that soybean oil, which diffuses less into hair, allows more water into hair than coconut oil. These preliminary results illustrate the utility of SANS for evaluating and understanding the diffusion of deuterated liquids into different morphological structures in hair.

  14. Magnetization processes in nanostructured metals and small-angle neutron scattering

    International Nuclear Information System (INIS)

    Loeffler, J.F.; Braun, H.B.; Wagner, W.; Kostorz, G.; Wiedenmann, A.

    2005-01-01

    The magnetization process in nanostructured (n-) Fe and Co was investigated via small-angle neutron scattering (SANS). In a zero field, the magnetization exhibits correlations extending over several grains. In intermediate applied magnetic fields around 1 kOe, n-Fe and n-Co samples with small grain sizes exhibit an anisotropic scattering profile with an unusual intensity enhancement for scattering vectors parallel to the field direction. Comparing the experimental data with a modeled granular microstructure containing magnetic domains of arbitrary size and orientation, we conclude that magnetic domains extending over several grains are tilted considerably out of the external field direction in intermediate fields. Since the domain size does not change significantly with the magnitude of the external field, we conclude that the magnetization process does not proceed via domain-wall motion. Together with theoretical arguments showing the existence of marginally stable domains within the random-anisotropy model, our SANS data suggests that the magnetization process proceeds by simultaneous reversal of a few adjacent domains, presumably in the form of small avalanches. This resembles the magnetization process predicted for random-field Ising magnets. Our theoretical analysis of SANS data is general and applies to other systems consisting of magnetic nanoclusters embedded in a nonmagnetic matrix

  15. Magnetization processes in nanostructured metals and small-angle neutron scattering

    Science.gov (United States)

    Löffler, J. F.; Braun, H. B.; Wagner, W.; Kostorz, G.; Wiedenmann, A.

    2005-04-01

    The magnetization process in nanostructured (n-) Fe and Co was investigated via small-angle neutron scattering (SANS). In a zero field, the magnetization exhibits correlations extending over several grains. In intermediate applied magnetic fields around 1kOe , n-Fe and n-Co samples with small grain sizes exhibit an anisotropic scattering profile with an unusual intensity enhancement for scattering vectors parallel to the field direction. Comparing the experimental data with a modeled granular microstructure containing magnetic domains of arbitrary size and orientation, we conclude that magnetic domains extending over several grains are tilted considerably out of the external field direction in intermediate fields. Since the domain size does not change significantly with the magnitude of the external field, we conclude that the magnetization process does not proceed via domain-wall motion. Together with theoretical arguments showing the existence of marginally stable domains within the random-anisotropy model, our SANS data suggests that the magnetization process proceeds by simultaneous reversal of a few adjacent domains, presumably in the form of small avalanches. This resembles the magnetization process predicted for random-field Ising magnets. Our theoretical analysis of SANS data is general and applies to other systems consisting of magnetic nanoclusters embedded in a nonmagnetic matrix.

  16. Magnetic nanostructures in FeNbB studied by small-angle neutron scattering

    International Nuclear Information System (INIS)

    Marcin, J.; Skorvanek, I.

    1999-01-01

    Complete text of publication follows. The evolution of nuclear and magnetic microstructure during crystallization of amorphous FeNbB alloys has been investigated by a small-angle neutron scattering in external magnetic field. Thermal annealing of the homogeneous as-quenched state of the melt-spun ribbons between 450 deg C and 650 deg C gives rise to a size distribution of bcc-Fe nanocrystals embedded in an amorphous remaining matrix. From nuclear and magnetic scattering at room temperature the size distributions of nanocrystals were determined as function of annealing temperature. An increase in the diameter of nanocrystalline particles was observed with increasing of annealing temperature. The magnetic and nuclear scattering contributions have been measured as function of external magnetic field and temperature. This allowed us to determine the Curie temperature value that corresponds to the residual amorphous matrix. The increase of T C (am) was observed with an increase of the annealing temperature. The observed behaviour is discussed in terms of model which take into account the magnetic interaction between constituent phases in investigated material. (author)

  17. A small angle neutron scattering study of isolated nanopores in a ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Raut Dessai, R. [Department of Physics, Goa University, Taleigao Plateau, Goa 403 206 (India); Desa, J.A.E., E-mail: erwindesa@gmail.com [Department of Physics, Goa University, Taleigao Plateau, Goa 403 206 (India); Sen, D.; Mazumder, S. [Solid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    2015-04-15

    Highlights: • Isolated nanopores in ceramic have been studied by SANS contrast variation. • The measured intensity was solely due to the presence of the isolated pores. • Concentration of isolated pores is substantially reduced at higher temperatures. • SANS is an effective tool to estimate isolated nanometric pores. - Abstract: The isolated pores in a silica ceramic sintered at 1073 K and 1273 K have been studied by small angle neutron scattering using the technique of scattering contrast factor variation. A mixture of H{sub 2}O and D{sub 2}O which matched the scattering length density of the ceramic matrix was introduced into the pores of the sample. The connected pores were thus contrast matched and hence the measured intensity was solely due to the presence of the isolated pores having no contrast matched liquid inside. Analysis of the data yielded a widely separated bi-modal distribution (with modes at ∼170 nm and 35 nm) of nanopores in the compacts. A qualitative model for the sintering in this ceramic is proposed where densification of the matrix occurs by annihilation of smaller pores. However, this is associated with enhancement in the number of larger pores through pore coalescence. In this description the connected pores both – macro and nano – increase in number – simultaneous with a decrease in numbers of isolated pores.

  18. A small angle neutron scattering study of isolated nanopores in a ceramic

    International Nuclear Information System (INIS)

    Raut Dessai, R.; Desa, J.A.E.; Sen, D.; Mazumder, S.

    2015-01-01

    Highlights: • Isolated nanopores in ceramic have been studied by SANS contrast variation. • The measured intensity was solely due to the presence of the isolated pores. • Concentration of isolated pores is substantially reduced at higher temperatures. • SANS is an effective tool to estimate isolated nanometric pores. - Abstract: The isolated pores in a silica ceramic sintered at 1073 K and 1273 K have been studied by small angle neutron scattering using the technique of scattering contrast factor variation. A mixture of H 2 O and D 2 O which matched the scattering length density of the ceramic matrix was introduced into the pores of the sample. The connected pores were thus contrast matched and hence the measured intensity was solely due to the presence of the isolated pores having no contrast matched liquid inside. Analysis of the data yielded a widely separated bi-modal distribution (with modes at ∼170 nm and 35 nm) of nanopores in the compacts. A qualitative model for the sintering in this ceramic is proposed where densification of the matrix occurs by annihilation of smaller pores. However, this is associated with enhancement in the number of larger pores through pore coalescence. In this description the connected pores both – macro and nano – increase in number – simultaneous with a decrease in numbers of isolated pores

  19. Nondestructive testing of high-temperature alloys by small angle neutron scattering (SANS)

    International Nuclear Information System (INIS)

    Widera, M.T.; Krautwasser, P.; Schuster, H.; Nickel, H.

    1992-11-01

    The suitability of the Small Angle Neutron Scattering (SANS) technique for the measurement of microstructural parameters of high-temperature alloys has been studied. The aim was the non-destructive determination of the creep damage for the estimation of the residual lifetime of service loaded gas turbine blades. In the first step the quantitative correlation between the SANS Signal and the microstructure of the material has been investigated using two oxide dispersion strengthened (ODS) alloys of simple microstructure. The size distributions of the dispersoid in the as-received alloy and the thermally induced growth of the dispersoid have been measured. Good agreement with results of transmission electron microscopy examinations was found. Subsequently the relationship between the SNS signal and the strain of a typical, creep loaded, γ'-strengthened Ni-base superalloy has been investigated. In a series of creep specimens made from the cast superalloy IN100, systematically increasing amounts of creep strain have been produced. With these specimens two parameters can be derived from the SANS scattering curve, each pair of values having a clear relationship with the creep strain. A hypothesis is discussed concerning the related scattering mechanism. (orig.) [de

  20. Exploring the bulk-phase structure of ionic liquid mixtures using small-angle neutron scattering.

    Science.gov (United States)

    Cabry, Christopher P; D'Andrea, Lucía; Shimizu, Karina; Grillo, Isabelle; Li, Peixun; Rogers, Sarah; Bruce, Duncan W; Canongia Lopes, José N; Slattery, John M

    2018-01-01

    Small-angle neutron scattering experiments, supported by molecular dynamics simulations, have been performed on a range of compositions of the [C 2 mim] 1-x [C 12 mim] x [Tf 2 N] ionic liquid mixture system. Isotopic contrast variation, through selective deuteration of both cations, has been used to assist in fitting the data to different scattering models. These data, and subsequent fitting, show that the structure of the ionic liquid mixtures changes substantially as a function of composition. Mixtures where x 0.32 can be described as bicontinuous, containing networks of both polar and non-polar domains, where the C12 chains of the [C 12 mim] + ions percolate through the system to form a continuous non-polar sub-phase. Temperature-dependent scattering experiments suggest that there is relatively little change in bulk structure in these liquids between 20 and 60 °C. The presence of water, however, does influence some aspects of the liquid structure in a composition that is rich in [C 2 mim][Tf 2 N] (where x = 0.24).

  1. Characterization of polymer adsorption onto drug nanoparticles using depletion measurements and small-angle neutron scattering.

    Science.gov (United States)

    Goodwin, Daniel J; Sepassi, Shadi; King, Stephen M; Holland, Simon J; Martini, Luigi G; Lawrence, M Jayne

    2013-11-04

    Production of polymer and/or surfactant-coated crystalline nanoparticles of water-insoluble drugs (nanosuspensions) using wet bead milling is an important formulation approach to improve the bioavailability of said compounds. Despite the fact that there are a number of nanosuspensions on the market, there is still a deficiency in the characterization of these nanoparticles where further understanding may lead to the rational selection of polymer/surfactant. To this end small-angle neutron scattering (SANS) measurements were performed on drug nanoparticles milled in the presence of a range of polymers of varying molecular weight. Isotopic substitution of the aqueous solvent to match the scattering length density of the drug nanoparticles (i.e., the technique of contrast matching) meant that neutron scattering resulted only from the adsorbed polymer layer. The layer thickness and amount of hydroxypropylcellulose adsorbed on nabumetone nanoparticles derived from fitting the SANS data to both model-independent and model dependent volume fraction profiles were insensitive to polymer molecular weight over the range Mv = 47-112 kg/mol, indicating that the adsorbed layer is relatively flat but with tails extending up to approximately 23 nm. The constancy of the absorbed amount is in agreement with the adsorption isotherm determined by measuring polymer depletion from solution in the presence of the nanoparticles. Insensitivity to polymer molecular weight was similarly determined using SANS measurements of nabumetone or halofantrine nanoparticles stabilized with hydroxypropylmethylcellulose or poly(vinylpyrrolidone). Additionally SANS studies revealed the amount adsorbed, and the thickness of the polymer layer was dependent on both the nature of the polymer and drug particle surface. The insensitivity of the adsorbed polymer layer to polymer molecular weight has important implications for the production of nanoparticles, suggesting that lower molecular weight polymers

  2. Membrane Structure Studies by Means of Small-Angle Neutron Scattering (SANS)

    International Nuclear Information System (INIS)

    Knott, R. B.

    2008-01-01

    summary of membrane structure will be followed by an outline of the neutron scattering techniques used to understand membrane structure and dynamics. The emphasis will be on the small angle neutron scattering technique since there is a very powerful instrument at Serpong, however brief mention of other techniques will be included to demonstrate how a multidisciplinary approach is usually required

  3. The time-of-flight small-angle scattering spectrometer SAN at the KENS pulsed cold neutron source

    International Nuclear Information System (INIS)

    Ishikawa, Y.; Furusaka, M.; Hasegawa, K.

    1986-01-01

    This paper describes the configuration and performance of a new time-of-flight (TOF) small-angle neutron scattering spectrometer SAN installed at the pulsed cold neutron source (KENS) at the National Laboratory for High Energy Physics (KEK). The spectrometer has advantages over conventional small-angle scattering apparatus: one is its capability for simultaneous measurements over a wide Q range (0.003≤Q≤4 A -1 ) and another is the new information that it provides by exploiting the wavelength dependence of the scattering. For example, the inelastic and elastic scattering can be separated without performing an energy analysis. The design principles of this type of spectrometer are also discussed. (orig.)

  4. Elucidation of density profile of self-assembled sitosterol + oryzanol tubules with small-angle neutron scattering

    NARCIS (Netherlands)

    Bot, A.; Gilbert, E.P.; Bouwman, W.G.; Sawalha, H.I.M.; Adel, den R.; Garamus, V.M.; Venema, P.; Linden, van der E.; Flöter, E.

    2012-01-01

    Small-angle neutron scattering (SANS) experiments have been performed on self-assembled tubules of sitosterol and oryzanol in triglyceride oils to investigate details of their structure. Alternative organic phases (deuterated and non-deuterated decane, limonene, castor oil and eugenol) were used to

  5. Study of the M23C6 precipitation in AISI 304 stainless steel by small angle neutron scattering

    International Nuclear Information System (INIS)

    Boeuf, A.; Caciuffo, R.G.M.; Institut Max von Laue - Paul Langevin, 38 - Grenoble; Ancona Univ.; Melone, S.; Puliti, P.; Rustichelli, F.; Institut Max von Laue - Paul Langevin, 38 - Grenoble; Ancona Univ.; Coppola, R.

    1985-01-01

    The results of some small-angle neutron scattering (SANS) experiments on M 23 C 6 (M=Fe, Cr) carbide precipitation in AISI 304 stainless steel, aged at different temperatures during different times, are presented. The total volume fraction, the total surface of precipitates per unit sample volume and the size distribution functions of the M 23 C 6 carbides were determined. (orig.)

  6. Spin-wave dynamics in Invar Fe65Ni35 studied by small-angle polarized neutron scattering

    NARCIS (Netherlands)

    Brück, E.H.; Grigoriev, S.V.; Deriglazov, V.V.; Okorokov, A.I.; Dijk van, N.H.; Klaasse, J.C.P.

    2002-01-01

    Abstract. Spin dynamics in Fe65Ni35 Invar alloy has been studied by left-right asymmetry of small-angle polarized neutron scattering below TC=485 K in external magnetic fields of H=0.05-0.25 T inclined relative to the incident beam. The spin-wave stiffness D and the damping & were obtained by

  7. Size and shape of the repetitive domain of high molecular weight wheat gluten proteins. 1. Small angle neutron scattering

    NARCIS (Netherlands)

    Egelhaaf, SU; van Swieten, E; Bosma, T; de Boef, E; van Dijk, AA; Robillard, GT; Egelhaaf, Stefan U.

    The solution structure of the central repetitive domain of high molecular weight (HMW) wheat gluten proteins has been investigated for a range of concentrations and temperatures using mainly small-angle neutron scattering. A representative part of the repetitive domain (dBl) was studied as well as

  8. Dipolar structures in magnetite ferrofluids studied with small-angle neutron scattering with and without applied magnetic field

    NARCIS (Netherlands)

    Klokkenburg, M.; Erne, B.H.; Wiedenmann, A.; Petukhov, A.V.; Philipse, A.P.

    2007-01-01

    Field-induced structure formation in a ferrofluid with well-defined magnetite nanoparticles with a permanent magnetic dipole moment was studied with small-angle neutron scattering (SANS) as a function of the magnetic interactions. The interactions were tuned by adjusting the size of the

  9. Low-temperature dynamics of magnetic colloids studied by time-resolved small-angle neutron scattering

    NARCIS (Netherlands)

    Wiedenmann, A.; Keiderling, U.; Meissner, M.; Wallacher, D.; Gähler, R.; May, R.P.; Prévost, S.; Klokkenburg, M.; Erne, B.H.; Kohlbrecher, J.

    2008-01-01

    The dynamics of ordering and relaxation processes in magnetic colloids has been studied by means of stroboscopic small angle neutron scattering techniques in an oscillating magnetic field. Surfactant stabilized ferrofluids (FFs) of Fe3O4 and Co nanoparticles have been investigated as a function of

  10. Small-Angle Neutron Scattering Study of Shear-Induced Phase Separation in Aqueous Poly(N-isopropylacrylamide) Solutions

    NARCIS (Netherlands)

    Stieger, M.A.; Lindner, P.; Richtering, W.

    2004-01-01

    The influence of shear flow on the structure of concentrated aqueous poly(N-isopropylacrylamide) solutions near the lower critical solution temperature was investigated by means of small-angle neutron scattering. Two samples, both in the semi-dilute regime above the overlap concentration, were

  11. Microstructural characterization of a modified 706-type Ni-Fe superalloy by small-angle neutron scattering and electron microscopy

    Czech Academy of Sciences Publication Activity Database

    Del Genovese, D.; Strunz, Pavel; Mukherji, D.; Gilles, R.; Rösler, J.

    36A, - (2005), s. 3439-3450 ISSN 1073-5623 Institutional research plan: CEZ:AV0Z10480505 Keywords : superalloys * small-angle neutron scattering Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.232, year: 2005

  12. Investigation of Monodisperse Dendrimeric Polysaccharide Nanoparticle Dispersions Using Small Angle Neutron Scattering

    Science.gov (United States)

    Atkinson, John; Nickels, Jonathan; Papp-Szabo, Erzsi; Katsaras, John; Dutcher, John

    2015-03-01

    Phytoglycogen is a highly branched polysaccharide that is very similar to the energy storage molecule glycogen. We have isolated monodisperse phytoglycogen nanoparticles from corn and these particles are attractive for applications in the cosmetic, food and beverage, and biomedical industries. Many of these promising applications are due to the special interaction between the nanoparticles and water, which results in: (1) high solubility; (2) low viscosity and high stability in aqueous dispersions; and (3) a remarkable capacity to sequester and retain water. Our rheology measurements indicate that the nanoparticles behave like hard spheres in water, with the viscosity diverging for concentrations >25% (w/w). Because of this, aqueous suspensions of phytoglycogen provide an ideal platform for detailed testing of theories of colloidal glasses and jamming. To further explore the interaction of the phytoglycogen particles and water, we have performed small angle neutron scattering (SANS) measurements on the Extended Q-Range SANS (EQ-SANS) diffractometer at the Spallation Neutron Source at Oak Ridge National Laboratory. Measurements performed on phytoglycogen dispersions in mixtures of hydrogenated and deuterated water have allowed us to determine the particle size and average particle spacing as a function of the phytoglycogen concentration in the limits of dilute and concentrated dispersions.

  13. Spin-Echo Small Angle Neutron Scattering analysis of liposomes and bacteria

    Science.gov (United States)

    van Heijkamp, Léon F.; Sevcenco, Ana-Maria; Abou, Diane; van Luik, Remko; Krijger, Gerard C.; Hagedoorn, Peter-Leon; de Schepper, Ignatz M.; Wolterbeek, Bert; Koning, Gerben A.; Bouwman, Wim G.

    2010-10-01

    Two types of liposomes, commonly used in drug delivery studies, and E. coli bacteria, all prepared in H2O, were resuspended in D2O and measured with Small Angle Spin-Echo Neutron Scattering (SESANS). Modeling was performed using correlation functions for solid spheres and hollow spheres. The signal strength and curve shape were more indicative of hollow particles, indicating that the H2O-D2O exchange occurred too fast to be observed with the available time resolution. Fitting the particle diameter and membrane thickness of the hollow sphere model to the data, gave results which were in good agreement with Dynamic Light Scattering (DLS) data and literature, showing as a proof-of-principle that SESANS is able to investigate such systems. SESANS may become a good alternative to conventional tritium studies or a tool with which to study intracellular vesicle transport phenomena, with possible in vivo applications. Calculations show that a substantial change in numbers of a mixed system of small and large biological particles should be observable. A possible application is the destruction by external means of great numbers of liposomes in the presence of tumor cells for triggered drug release in cancer treatment. Since SESANS is both non-invasive and non-destructive and can handle relatively thick samples, it could be a useful addition to more conventional techniques.

  14. Monomeric Amyloid Beta Peptide in Hexafluoroisopropanol Detected by Small Angle Neutron Scattering.

    Directory of Open Access Journals (Sweden)

    Bo Zhang-Haagen

    Full Text Available Small proteins like amyloid beta (Aβ monomers are related to neurodegenerative disorders by aggregation to insoluble fibrils. Small angle neutron scattering (SANS is a nondestructive method to observe the aggregation process in solution. We show that SANS is able to resolve monomers of small molecular weight like Aβ for aggregation studies. We examine Aβ monomers after prolonged storing in d-hexafluoroisopropanol (dHFIP by using SANS and dynamic light scattering (DLS. We determined the radius of gyration from SANS as 1.0±0.1 nm for Aβ1-40 and 1.6±0.1 nm for Aβ1-42 in agreement with 3D NMR structures in similar solvents suggesting a solvent surface layer with 5% increased density. After initial dissolution in dHFIP Aβ aggregates sediment with a major component of pure monomers showing a hydrodynamic radius of 1.8±0.3 nm for Aβ1-40 and 3.2±0.4 nm for Aβ1-42 including a surface layer of dHFIP solvent molecules.

  15. Monomeric Amyloid Beta Peptide in Hexafluoroisopropanol Detected by Small Angle Neutron Scattering.

    Science.gov (United States)

    Zhang-Haagen, Bo; Biehl, Ralf; Nagel-Steger, Luitgard; Radulescu, Aurel; Richter, Dieter; Willbold, Dieter

    2016-01-01

    Small proteins like amyloid beta (Aβ) monomers are related to neurodegenerative disorders by aggregation to insoluble fibrils. Small angle neutron scattering (SANS) is a nondestructive method to observe the aggregation process in solution. We show that SANS is able to resolve monomers of small molecular weight like Aβ for aggregation studies. We examine Aβ monomers after prolonged storing in d-hexafluoroisopropanol (dHFIP) by using SANS and dynamic light scattering (DLS). We determined the radius of gyration from SANS as 1.0±0.1 nm for Aβ1-40 and 1.6±0.1 nm for Aβ1-42 in agreement with 3D NMR structures in similar solvents suggesting a solvent surface layer with 5% increased density. After initial dissolution in dHFIP Aβ aggregates sediment with a major component of pure monomers showing a hydrodynamic radius of 1.8±0.3 nm for Aβ1-40 and 3.2±0.4 nm for Aβ1-42 including a surface layer of dHFIP solvent molecules.

  16. Characterization of lysozyme adsorption in cellulosic chromatographic materials using small-angle neutron scattering.

    Science.gov (United States)

    Koshari, Stijn H S; Wagner, Norman J; Lenhoff, Abraham M

    2015-06-19

    Measurements of the nanoscale structure of chromatographic adsorbents and the associated distribution of sorbed protein within the media can facilitate improvements in such media. We demonstrate a new technique for this purpose using small-angle neutron scattering (SANS) to characterize the nano- to microscale structure of the chromatographic media and sorbed protein under conditions relevant for preparative chromatographic separations. The adsorption of lysozyme on cellulosic S HyperCel™ (Pall Corporation), a strong cation exchanger, was investigated by SANS. The scattering spectrum is reduced to three contributions arising from (1) the chromatographic medium, (2) discrete protein molecules, and (3) the distribution of sorbed protein within the medium. These contributions are quantified for a range of protein loadings. The total concentration of protein in the chromatographic media can be quantified from the SANS spectrum and the protein is observed to retain its tertiary structure upon adsorption, within the resolution of the method. Further analysis of the SANS spectra shows that protein adsorption is uniform in the media. These measurement techniques provide new and valuable nanoscale information about protein sorption in chromatographic media. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Small-angle neutron scattering investigation of polyurethane aged in dry and wet air

    Directory of Open Access Journals (Sweden)

    Q. Tian

    2014-05-01

    Full Text Available The microstructures of Estane 5703 aged at 70°C in dry and wet air have been studied by small-angle neutron scattering. The samples were swollen in deuterated toluene for enhancing the contrast. The scattering data show the characteristic domain structure of polyurethanes consisting of soft and hard segments. Debye-Anderson-Brumberger function used with hard sphere structure factor, and the Teubner-Strey model are used to analyze the two-phase domain structure of the polymer. The combined effects of temperature and humidity have a strong disruption effect on the microstructures of Estane. For the sample aged at 70°C in wet air for 1 month, the domain size, described by the correlation length, increases from 2.3 to 3.8 nm and their distance, expressed by hard-sphere interaction radius, increases from 8.4 to 10.6 nm. The structure development is attributed to degradation of polymer chains as revealed by gel permeation chromatography. The hydrolysis of ester links on polymer backbone at 70°C in the presence of water humidity is the main reason for the changes of the microstructure. These findings can contribute to developing predictive models for the safety, performance, and lifetime of polyurethanes.

  18. Small-angle neutron scattering reveals the assembly of alpha-synuclein in lipid membranes.

    Science.gov (United States)

    Anunciado, Divina; Rai, Durgesh K; Qian, Shuo; Urban, Volker; O'Neill, Hugh

    2015-12-01

    The aggregation of α-synuclein (asyn), an intrinsically disordered protein (IDP), is a hallmark in Parkinson's disease (PD). We investigated the conformational changes that asyn undergoes in the presence of membrane and membrane mimetics using small-angle neutron scattering (SANS). In solution, asyn is monomeric and unfolded assuming an ensemble of conformers spanning extended and compact conformations. Using the contrast variation technique and SANS, the protein scattering signal in the membrane-protein complexes is selectively highlighted in order to monitor its conformational changes in this environment. We showed that in the presence of phospholipid membranes asyn transitions from a monodisperse state to aggregated structures with sizes ranging from 200 to 900Å coexisting with the monomeric species. Detailed SANS data analysis revealed that asyn aggregates have a hierarchical organization in which clusters of smaller asyn aggregates assemble to form the larger structures. This study provides new insight into the mechanism of asyn aggregation. We propose an aggregation mechanism in which stable asyn aggregates seed the aggregation process and hence the hierarchical assembly of structures. Our findings demonstrate that membrane-induced conformational changes in asyn lead to its heterogeneous aggregation which could be physiologically relevant in its function or in the diseased state. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Polarized small angle neutron scattering of MnO/Mn3O4 nanocrystals

    Science.gov (United States)

    Dedon, L.; Ijiri, Y.; Booth, R.; Krycka, K.; Borchers, J. A.; Chen, W. C.; Watson, S.; Rhyne, J. J.; Majetich, S. A.

    2012-02-01

    Monodisperse magnetic nanoparticles are of great interest for biomedical and data storage applications, particularly in cases where the core and shell can be carefully controlled to alter properties like magnetic anisotropy. However, it is often difficult to determine the underlying moment arrangements and correlations in these systems. Here, we focus on manganese (II) oxide/manganese (II,III) oxide core/shell nanoparticles, using polarized small angle neutron scattering (SANS) to probe the magnetic intra and interparticle interactions. The 30nm diameter particles with 4-5nm shell were prepared by solution chemistry methods and self-assembled into 3D nanocrystals. SANS measurements were conducted in magnetic fields from remanence-1T and temperatures from 10-300K. Magnetic and structural scattering components were separated using an algorithm previously described in [1]. The magnetic signature depended on the field and temperature history of the sample. Modeling work has been done to further quantify the interparticle length scales and the effects of crystal packing. This work was supported in part by NSF grants DMR-0454672, -0704178, -0804779, -1104489, and DOE grant DE-FG02-08ER40481. [1] K.L. Krycka, et al. Phys. Rev. Lett. 104, 207203 (2010).

  20. Small-angle neutron scattering study of magnetic microstructures in Co-Cr films

    International Nuclear Information System (INIS)

    Suzuki, J.; Morii, Y.; Maeda, Y.

    1998-01-01

    We report a small-angle neutron scattering (SANS) study of the influence of compositional separation (CS) on the magnetic microstructure of sputtered Co-22 at% Cr thin films deposited at substrate temperatures (T S ) of 40-400 C. Using vibrating sample magnetometry and nuclear magnetic resonance, we observed that CS producing a Co-enriched component develops as T S increases and becomes most prominent at around 250 C with a maximum saturation magnetization. At T S over 400 C compositional homogenization occurs. The SANS spectra show that all the films exhibit much larger scattering cross-sections than that of a compositionally homogeneous Co-22 at% Cr bulk alloy sample. This indicates that CS promotes both magnetic and chemical microstructures in the thin films. The SANS spectra are observed to change systematically with the variation in T S . An analysis of these spectra suggests that CS produces in-grain columnar magnetic microstructures with small sizes of several nanometers at T S of 40-200 C, and these microstructures become particulate at T S of 300 and 400 C, where compositional homogenization occurs. It is shown that T S is a critical factor in the formation of the magnetic microstructures. (orig.)

  1. Small-angle neutron scattering study of D2O-alcohol solutions

    International Nuclear Information System (INIS)

    D'Arrigo, G.

    1990-01-01

    Small-angle neutron scattering (SANS) measurements have been carried out on heavy water solutions of ethanol, isopropyl alcohol, n-propyl alcohol, t-butyl alcohol and butoxyethanol between 5 and 37 0 C at the concentrations where ultrasonic attenuation exhibits peak values. The wavevector dependence and the absolute intensity of the scattered intensities were analysed according to a microscopic model of the solutions in terms of aggregated complexes. The results indicate that at 25 0 C there exist either alcohol 'micelle-like' structures or alcohol-heavy water complexes which increase on going from the lower to higher alcohol solutions. As temperature increases from 25 to 37 0 C a higher aggregation is observed in butyl alcohol and butoxyethanol solutions. This behaviour is attributed to the demixing tendency of these systems at high temperatures. On going from 25 to 5 0 C the aggregation increases again. This trend is associated with the anomalous behaviour of the specific heat and ultrasonic attenuation of these systems. The occurrence of a low-temperature phase transition suggested by these anomalies is supported by our results. (author)

  2. Ultra-small-angle neutron scattering: large-scale structure determination from a bird's eye view

    International Nuclear Information System (INIS)

    Rehma, A.; Brûlé, A.; Freund, A.; Kennedy, S.

    2012-01-01

    Both natural and synthetic materials science and engineering rely increasingly on detailed knowledge of the microstructure and interactions in soft and hard materials. Contemporary research areas in biology and the life sciences, e.g., include membrane biophysics, drug-delivery systems and pharmacology, denial and medical composites, biomaterials, fillings and implants in each of these areas large length scale measurements become necessary as model biological systems begin to approach the complexity of natural systems Porosity (void structure) and particle size need to be understood so that the processes of agglomeration and water transport can be quantified in materials such as cements, oil bearing rooks, and pewit pigments Complex fluids, containing structures and complexes in the nanometre and much larger length scales, have widely varying physical properties and are extensively used in food, cosmetic/personal care, pharmaceuticals and drug-delivery, and mining industries. In these length-scales are some of the organisational features that dictate the bulk rheological and stability properties of solutions. At ANSTO a new ultra-small-angle neutron scattering (USANS) instrument, Kookaburra (currently) under construction with an expected transition to operation in mid-2013), will advance large-scale structure determination in the size range of 0.1-10 µm. Based on the well-established Bonse-Hart method. Kookaburra will individually operate at two different wavelengths to optimally accommodate weakly and strongly scattering samples at one sample position. This contribution will present specifics of Kookaburra and also discuss a practical application of the USANS technique in polymer science. Both its versatility and estimated neutron flux suggest that this state-.of-the-art instrument will generate a major impact in the field of large-scale structure determination.

  3. Interphase effects in dental nanocomposites investigated by small-angle neutron scattering.

    Science.gov (United States)

    Wilson, Kristen S; Allen, Andrew J; Washburn, Newell R; Antonucci, Joseph M

    2007-04-01

    Small-angle and ultrasmall-angle neutron scattering (SANS and USANS) were used to characterize silica nanoparticle dispersion morphologies and the interphase in thermoset dimethacrylate polymer nanocomposites. Silica nanoparticle fillers were silanized with varying mass ratios of 3-methacryloxypropyltrimethoxysilane (MPTMS), a silane that interacts with the matrix through covalent and H-bonding, and n-octyltrimethoxysilane (OTMS), a silane that interacts through weak dispersion forces. Interphases with high OTMS mass fractions were found to be fractally rough with fractal dimensions, D(s), between 2.19 and 2.49. This roughness was associated with poor interfacial adhesion and inferior mechanical properties. Mean interparticle distances calculated for composites containing 10 mass % and 25 mass % silica suggest that the nanoparticles treated with more MPTMS than OTMS may be better dispersed than OTMS-rich nanoparticles. The results indicate that the covalent bonding and H-bonding of MPTMS-rich nanoparticles with the matrix are necessary for preparing well-dispersed nanocomposites. In addition, interphases containing equal masses of MPTMS and OTMS may yield composites with overall optimal properties. Finally, the combined SANS/USANS data could distinguish the differences, as a function of silane chemistry, in the nanoparticle/silane and silane/matrix interfaces that affect the overall mechanical properties of the composites. (c) 2006 Wiley Periodicals, Inc.

  4. Neutron scattering from fractals

    DEFF Research Database (Denmark)

    Kjems, Jørgen; Freltoft, T.; Richter, D.

    1986-01-01

    -angle neutron scattering studies of the variation with aggregation rate are presented. These results allow a very detailed comparison to be made with the theoretical scattering curves. Preliminary incoherent inelastic data on the low-frequency dynamics of hydroxylated silica particle aggregates show a clear...

  5. Tandem analyzer crystals system doubles counting rate for Bonse-Hart ultra-small-angle neutron-scattering spectrometer

    International Nuclear Information System (INIS)

    Yamaguchi, Daisuke; Koizumi, Satoshi; Motokawa, Ryuhei; Kumada, Takayuki; Aizawa, Kazuya; Hashimoto, Takeji

    2006-01-01

    A new tandem analyzer crystals system was introduced on Bonse-Hart ultra-small-angle neutron-scattering spectrometer at research reactor JRR-3, Tokai, Japan. Conventional Bonse-Hart setup consumes a considerable time to measure a scattering profile of whole q range (2x10 -4 nm -1 -2 nm -1 , where q denotes magnitude of scattering vector) due to the step scan system, in which the scattered neutrons from the sample and having different q are measured step by step. To overcome this difficulty two analyzer channel-cut silicon perfect crystals were settled in tandem and each of them diffracted the scattering of different q. In consequence, a simultaneous detection at two different q positions was realized and the measurement time was reduced to half

  6. Characterization of a chromia-alumina catalyst using small-angle neutron scattering

    International Nuclear Information System (INIS)

    Acharya, D.R.; Crowley, T.L.; Hughes, R.; Koon, C.L.

    1990-01-01

    Neutron scattering has been employed to study the pore structure of a chromia-alumina catalyst. The results indicated the existence of three distinct scattering regimes with distinct slopes corresponding to the values of the waste vector, Q. The analysis of the scattering in these regions suggested that the large-Q region corresponds to Porod's law scattering and provides information on the specific surface area. The intermediate Q region arises from scattering from hollow capillaries and provides information on the dimension of the capillaries. The small-Q behaviour arises from the relative spatial arrangement of capillaries, which appear to form a 'fractal' network. (orig.)

  7. Field-induced self-assembly of iron oxide nanoparticles investigated using small-angle neutron scattering.

    Science.gov (United States)

    Fu, Zhendong; Xiao, Yinguo; Feoktystov, Artem; Pipich, Vitaliy; Appavou, Marie-Sousai; Su, Yixi; Feng, Erxi; Jin, Wentao; Brückel, Thomas

    2016-11-03

    The magnetic-field-induced assembly of magnetic nanoparticles (NPs) provides a unique and flexible strategy in the design and fabrication of functional nanostructures and devices. We have investigated the field-induced self-assembly of core-shell iron oxide NPs dispersed in toluene by means of small-angle neutron scattering (SANS). The form factor of the core-shell NPs was characterized and analyzed using SANS with polarized neutrons. Large-scale aggregates of iron oxide NPs formed above 0.02 T as indicated by very-small-angle neutron scattering measurements. A three-dimensional long-range ordered superlattice of iron oxide NPs was revealed under the application of a moderate magnetic field. The crystal structure of the superlattice has been identified to be face-centred cubic.

  8. Characterization of nanoparticles of lidocaine in w/o microemulsions using small-angle neutron scattering and dynamic light scattering

    International Nuclear Information System (INIS)

    Shukla, A.; Kiselev, M.A.; Hoell, A.; Neubert, R.H.H.

    2004-01-01

    Microemulsions (MEs) are of special interest because a variety of reactants can be introduced into the nanometer-sized aqueous domains, leading to materials with controlled size and shape. In the past few years, significant research has been conducted in the reverse ME-mediated synthesis of organic nanoparticles. In this study, a w/o ME medium was employed for the synthesis of lidocaine by direct precipitation in w/o microemulsion systems: water/isopropylpalmitat/Tween80/Span80. The particle size as well as the location of nanoparticles in the ME droplet were characterized by means of dynamic light scattering (DLS) and small angle neutron scattering (SANS). It is observed that lidocaine precipitated in the aqueous cores because of its insolubility in water. Hydrodynamic radius and gyration radius of microemulsion droplets were estimated as ∼15 nm and ∼4.50 nm from DLS and SANS respectively. Furthermore, different size parameters obtained by DLS and SANS experiments were compared. (author)

  9. Structural studies of Neurospora crassa LPMO9D and redox partner CDHIIA using neutron crystallography and small-angle scattering.

    Science.gov (United States)

    Bodenheimer, Annette M; O'Dell, William B; Stanley, Christopher B; Meilleur, Flora

    2017-08-07

    Sensitivity to hydrogen/deuterium and lack of observable radiation damage makes cold neutrons an ideal probe the structural studies of proteins with highly photosensitive groups such as the copper center of lytic polysaccharide monooxygenases (LPMOs) and flavin adenine dinucleotide (FAD) and heme redox cofactors of cellobiose dehydrogenases (CDHs). Here, neutron crystallography and small-angle neutron scattering are used to investigate Neurospora crassa LPMO9D (NcLPMO9D) and CDHIIA (NcCDHIIA), respectively. The presence of LPMO greatly enhances the efficiency of commercial glycoside hydrolase cocktails in the depolymerization of cellulose. LPMOs can receive electrons from CDHs to activate molecular dioxygen for the oxidation of cellulose resulting in chain cleavage and disruption of local crystallinity. Using neutron protein crystallography, the hydrogen/deuterium atoms of NcLPMO9D could be located throughout the structure. At the copper active site, the protonation states of the side chains of His1, His84, His157 and Tyr168, and the orientation of water molecules could be determined. Small-angle neutron scattering measurements provided low resolution models of NcCDHIIA with both the dehydrogenase and cytochrome domains in oxidized states that exhibited elongated conformations. This work demonstrates the suitability of neutron diffraction and scattering for characterizing enzymes critical to oxidative cellulose deconstruction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. A high-temperature cell for in situ small-angle neutron scattering studies of phase separation in alloys

    Science.gov (United States)

    Kompatscher, M.; Bär, M.; Hecht, J.; Muheim, C.; Kohlbrecher, J.; Kostorz, G.; Wagner, W.

    2002-12-01

    A furnace for small-angle neutron scattering on samples heated from room temperature to 1500°C was constructed and is now available on the SANS instrument at the spallation source SINQ of the Paul Scherrer Institut in Villigen, Switzerland. Solid solution treatments and quick temperature steps are feasible combined with a motorized positioning system to precisely adjust the sample. The furnace works under high vacuum (better than 10 -4 mbar) or under controlled atmosphere. Special measures were taken to reduce parasitic scattering from the sample environment. Remote control when installed on the instrument as well as stand-alone operation for calibration and test purposes are feasible. Results of small-angle neutron scattering experiments on a polycrystal and a single crystal of Ni-11.3 at% Ti aged in situ at 600°C for up to 100 h are presented.

  11. Focusing and polarized neutron ultra-small-angle scattering spectrometer (SANS-J-II) at Research Reactor JRR3, Japan

    International Nuclear Information System (INIS)

    Koizumi, Satoshi; Iwase, Hiroki; Suzuki, Jun-ichi; Oku, Takayuki; Motokawa, Ryuhei; Sasao, Hajime; Tanaka, Hirokazu; Yamaguchi, Daisuke; Shimizu, Hirohiko M.; Hashimoto, Takeji

    2006-01-01

    By employing focusing lenses of sextupole permanent magnet and biconcave MgF 2 crystal, and high-resolution photomultiplier, SANS-J (pinhole small-angle neutron scattering spectrometer at research reactor JRR3, Tokai) was reconstructed to focusing and polarized neutron ultra-small-angle scattering spectrometer (SANS-J-II). Consequently, an accessible minimum wave number q min was improved from 3x10 -3 A -1 to 3x10 -4 A -1 . Furthermore, we added 3 He sub-detectors with an analyzer super mirror at a sample position. With this setup, we perform polarization analysis at high q (>0.2 A -1 ) in order to quantitatively discriminate spin incoherent scattering from hydrogen or to perform spin contrast variation, by a dynamic nuclear polarization method (>0.2 A -1 )

  12. Core-shell structure of degradable, thermosensitive polymeric micelles studied by small-angle neutron scattering.

    Science.gov (United States)

    Ramzi, Aissa; Rijcken, Cristianne J F; Veldhuis, Theo F J; Schwahn, Dietmar; Hennink, Wim E; van Nostrum, Cornelus F

    2008-01-24

    The structure of assemblies of block copolymers composed of thermosensitive, biodegradable poly(N-(2-hydroxypropyl) methacrylamide-dilactate) and poly(ethylene glycol) (pHPMAmDL-b-PEG) has been studied by small-angle neutron scattering (SANS). Three amphiphilic copolymers with a fixed PEG of 5 kDa and a partially deuterated pHPMAmDL(d) block of 6700, 10400, or 21200 Da were used to form micelles in aqueous media by heating the polymeric solution from below to above the cloud point temperature (around 10 degrees C) of the thermosensitive block. Simultaneous and quantitative analysis of the scattering cross sections obtained at three different solvent contrasts is expedited using core-shell model, which assumed a homogeneous core of uniform scattering length density. The mean core radius increased from 13 to 18.5 nm with the molecular weight of the pHPMAmDL(d) block, while the thickness of the stabilizing PEG layer was around 8 nm for the three investigated assemblies. In addition, the volume fraction values of the stabilizing PEG chains in the shell are low and decreased from 31% to 14% with increasing the size of pHPMAmDL(d) block which shows that the shell layer of the assemblies is highly hydrated. The corresponding PEG chain grafting densities decreased from 0.22 to 0.11 nm-2 and the distance between PEG chains on the nanoparticles surface increased from 2.4 to 3.4 nm. The pHPMAmDL-b-PEG micelles showed a controlled instability due to hydrolysis of the lactic acid side groups in the thermosensitive block; that is, an increase of the degradation time leads to an increase of the size of the core which becomes less hydrophobic and consequently more hydrated. Neutron experiments supplied accurate information on how the size of the core and the micelle's aggregation number changed with the incubation time. This feature and the initially small size and dense structure in aqueous solution make the polymeric micelles suitable as carriers for hydrophobic drugs.

  13. Neutron scattering

    International Nuclear Information System (INIS)

    1991-02-01

    The annual report on hand gives an overview of the research work carried out in the Laboratory for Neutron Scattering (LNS) of the ETH Zuerich in 1990. Using the method of neutron scattering, it is possible to examine in detail the static and dynamic properties of the condensed material. In accordance with the multidisciplined character of the method, the LNS has for years maintained a system of intensive co-operation with numerous institutes in the areas of biology, chemistry, solid-state physics, crystallography and materials research. In 1990 over 100 scientists from more than 40 research groups both at home and abroad took part in the experiments. It was again a pleasure to see the number of graduate students present, who were studying for a doctorate and who could be introduced into the neutron scattering during their stay at the LNS and thus were in the position to touch on central ways of looking at a problem in their dissertation using this modern experimental method of solid-state research. In addition to the numerous and interesting ways of formulating the questions to explain the structure, nowadays the scientific programme increasingly includes particularly topical studies in connection with high temperature-supraconductors and materials research

  14. Preparing monodisperse macromolecular samples for successful biological small-angle X-ray and neutron-scattering experiments.

    Science.gov (United States)

    Jeffries, Cy M; Graewert, Melissa A; Blanchet, Clément E; Langley, David B; Whitten, Andrew E; Svergun, Dmitri I

    2016-11-01

    Small-angle X-ray scattering (SAXS) and small-angle neutron scattering (SANS) are techniques used to extract structural parameters and determine the overall structures and shapes of biological macromolecules, complexes and assemblies in solution. The scattering intensities measured from a sample contain contributions from all atoms within the illuminated sample volume, including the solvent and buffer components, as well as the macromolecules of interest. To obtain structural information, it is essential to prepare an exactly matched solvent blank so that background scattering contributions can be accurately subtracted from the sample scattering to obtain the net scattering from the macromolecules in the sample. In addition, sample heterogeneity caused by contaminants, aggregates, mismatched solvents, radiation damage or other factors can severely influence and complicate data analysis, so it is essential that the samples be pure and monodisperse for the duration of the experiment. This protocol outlines the basic physics of SAXS and SANS, and it reveals how the underlying conceptual principles of the techniques ultimately 'translate' into practical laboratory guidance for the production of samples of sufficiently high quality for scattering experiments. The procedure describes how to prepare and characterize protein and nucleic acid samples for both SAXS and SANS using gel electrophoresis, size-exclusion chromatography (SEC) and light scattering. Also included are procedures that are specific to X-rays (in-line SEC-SAXS) and neutrons, specifically preparing samples for contrast matching or variation experiments and deuterium labeling of proteins.

  15. Small-angle neutron scattering studies of the template-mediated crystallization of ZSM-5 type zeolite

    International Nuclear Information System (INIS)

    Iton, L.E.; Brun, T.O.; Epperson, J.E.

    1988-03-01

    Small-angle neutron scattering is a useful new approach to the study of zeolite crystallization from aluminosilicate gels and the action of template molecules. It has been applied to gels for synthesis of zeolite ZSM-5 using tetrapropylammonium ions as templates where the scattering length densities of the gel particles and their texture were determined using contrast variation methods. Gels formulated from soluble silicate incorporate template molecules promptly into an amorphous ''embryonic'' structure and crystallization ensues via a solid hydrogel transformation mechanism. Gels formulated from colloidal silica show different scattering behavior, and a liquid phase transport mechanism is inferred. 8 refs., 4 figs., 2 tabs

  16. Monitoring thylakoid ultrastructural changes in vivo using small-angle neutron scattering.

    Science.gov (United States)

    Unnep, Renáta; Nagy, Gergely; Markó, Márton; Garab, Győző

    2014-08-01

    The light reactions of oxygenic photosynthesis take place in the thylakoid membranes, flattened vesicles, which contain the two photosystems and also embed the cytochrome b6f complex and the ATP synthase. In general, the thylakoid membranes are assembled into multilamellar membrane systems, which warrant an optimal light capturing efficiency. In nature, they show astounding variations, primarily due to large variations in their protein composition, which is controlled by multilevel regulatory mechanisms during long-term acclimation and short-term adaptation processes and also influenced by biotic or abiotic stresses - indicating a substantial degree of flexibility in the membrane ultrastructure. The better understanding of the dynamic features of this membrane system requires the use of non-invasive techniques, such as small angle neutron scattering (SANS), which is capable of providing accurate, statistically and spatially averaged information on the repeat distances of periodically organized thylakoid membranes under physiologically relevant conditions with time resolutions of seconds and minutes. In this review, after a short section on the basic properties of neutrons, we outline the fundamental principles of SANS measurements, its strengths and weaknesses in comparison to complementary structure investigation techniques. Then we overview recent results on isolated plant thylakoid membranes, and on living cyanobacterial and algal cells as well as on whole leaves. Special attention is paid to light-induced reversible ultrastructural changes in vivo, which, in cyanobacterial and diatom cells, were uncovered with the aid of SANS measurements; we also discuss the role of membrane reorganizations in light adaptation and photoprotection mechanisms. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  17. Structural formation of huntingtin-like aggregates probed by small-angle neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Stanley, Christopher B [ORNL; Perevozchikova, Tatiana [ORNL; Berthelier-Jung, Valerie M [ORNL

    2011-01-01

    In several neurodegenerative disorders, including Huntington s disease (HD), aspects concerning the earliest of protein structures that form along the aggregation pathway have increasingly gained attention since these particular species are likely to be neurotoxic. We used time-resolved small-angle neutron scattering (SANS) to probe in solution these transient structures formed by peptides having the N-terminal sequence context of mutant huntingtin (Htt) exon 1. We obtained snapshots of the formed aggregates as the kinetic reaction ensued to yield quantitative information on their size and mass. At the early stage, small precursor species with an initial radius of gyration (Rg) of 16.1 5.9 and average mass of a dimer to trimer were monitored. Structural growth was treated as two modes with a transition from three-dimensional early aggregate formation to two-dimensional fibril growth and association. Our SANS results on the internal structure of the mature fibrils demonstrate loose packing with about 1 peptide per 4.75 -sheet repeat distance, which is shown to be quantitatively consistent with a -helix model. This research provides new insights into the structures forming along the pathway of Htt exon 1 aggregation and should assist in determining the role that precursors play in neuronal toxicity.

  18. Application of small-angle neutron scattering to the study of porosity in energetic materials

    International Nuclear Information System (INIS)

    Mang, Joseph T.; Skidmore, Cary B.; Hjelm, Rex P.; Howe, Philip M.

    2000-01-01

    Small-angle neutron scattering (SANS) and the method of contrast variation were used to measure porosity and crystallite surface area in the energetic system octahydro-1, 3, 5, 7- tetranitro-1, 3, 5, 7-tetrazocine (HMX) and to gauge the effects of mechanical deformation on the pore-size distribution and crystallite surface area. The crystallite surface area and the presence of voids (pores) in a high explosive system are known to affect its behavior and overall performance. Measures of these two quantities after an insult, resulting from various process and accident scenarios, can be used to predict the performance of an explosive system after process- and accident-related mechanical deformation. The contrast variation technique allows us to discriminate between internal pores and features that are on or contiguous with the crystallite surface. Measurements were conducted on loose powders of HMX (261 and 10 μm, volume averaged mean particle diameters) and pellets made by uniaxial consolidation to 7 and 10 vol% porosity, respectively. Analysis of the SANS data indicates significant alteration of the intragranular pore structure and systematic shifts in the surface area that are dependent upon mechanical deformation. (c) 2000 Materials Research Society

  19. Nanostructures and ordering phenomena in ferrofluids investigated using polarized small angle neutron scattering

    International Nuclear Information System (INIS)

    Wiedenmann, A; Kammel, M; Heinemann, A; Keiderling, U

    2006-01-01

    Polarized small angle neutron scattering (SANSPOL) was used to investigate the microstructure of various ferrofluids (FF) where magnetic materials (Co, Fe magnetite), stabilization mechanisms (electrostatic, monolayers and bilayers of surfactants) and carrier liquids (water, organic solvents) have been systematically varied. Magnetic core-shell particles, non-magnetic micelles and magnetic aggregates were identified and size distributions and density, composition, and magnetization profiles were determined. Partial penetrations of solvent molecules inside the surfactant layer and formation of non-magnetic oxide coatings were established. The magnetic nanostructure in diluted samples consists of non-interacting ferromagnetic single domain particles. In concentrated Co FF a pseudo-crystalline ordering was found to be induced by an external magnetic field where cobalt core-shell particles are arranged in hexagonal planes. The particle ordering and magnetic moment direction followed the direction of the applied field. In addition, segments of uncorrelated dipolar chains were found to be present. The dynamics of the field induced ordering was studied by means of time-resolved SANS. Individual particle moments are stuck by field induced dipolar interactions in domains of local hexagonal ordering which relax by rotational diffusion when the field is switched off, with a characteristic time of a few seconds

  20. Nanostructures and ordering phenomena in ferrofluids investigated using polarized small angle neutron scattering

    Science.gov (United States)

    Wiedenmann, A.; Kammel, M.; Heinemann, A.; Keiderling, U.

    2006-09-01

    Polarized small angle neutron scattering (SANSPOL) was used to investigate the microstructure of various ferrofluids (FF) where magnetic materials (Co, Fe magnetite), stabilization mechanisms (electrostatic, monolayers and bilayers of surfactants) and carrier liquids (water, organic solvents) have been systematically varied. Magnetic core-shell particles, non-magnetic micelles and magnetic aggregates were identified and size distributions and density, composition, and magnetization profiles were determined. Partial penetrations of solvent molecules inside the surfactant layer and formation of non-magnetic oxide coatings were established. The magnetic nanostructure in diluted samples consists of non-interacting ferromagnetic single domain particles. In concentrated Co FF a pseudo-crystalline ordering was found to be induced by an external magnetic field where cobalt core-shell particles are arranged in hexagonal planes. The particle ordering and magnetic moment direction followed the direction of the applied field. In addition, segments of uncorrelated dipolar chains were found to be present. The dynamics of the field induced ordering was studied by means of time-resolved SANS. Individual particle moments are stuck by field induced dipolar interactions in domains of local hexagonal ordering which relax by rotational diffusion when the field is switched off, with a characteristic time of a few seconds.

  1. Structural analysis of inorganic semiconducting nanosheet colloids with small-angle neutron scattering and photofunctions

    International Nuclear Information System (INIS)

    Miyamoto, Nobuyoshi

    2009-01-01

    I built up an apparatus for in-situ measurements of small-angle neutron scattering (SANS) concurrently with UV-visible spectroscopy under UV-irradiation; by using this apparatus, I investigated the structural change during photoinduced electron transfer reactions in aqueous colloidal systems composed of semiconductor liquid crystalline nanosheets, clay mineral nanosheets, and an electron acceptor methylviologen. In the visible spectrum after UV-irradiation, broad band (600 - 800 nm) due to excited electrons in the niobate nanosheets and a peak (600 nm) due to methylviologen radical cations were observed, accompanied by a SANS signal (a peak at q = 0.095 nm -1 ). The aborbance and SANS intensity varied with irradiation time and intensity of UV-light. I suppose that the structure of the colloid was modified due to the change in nanosheet charges upon photo-induced electron transfer reaction. Similar photochemical reactions were also observed for the colloidal systems containing newly found liquid crystalline clay mineral nanosheets (fluorohectorite and fluortetrasilisic mica) in stead of hectorite. (author)

  2. Small-angle neutron scattering study of shearing effects on drag-reducing surfactant solutions.

    Science.gov (United States)

    Qi, Yunying; Littrell, Kenneth; Thiyagarajan, Pappannan; Talmon, Yeshayahu; Schmidt, Judith; Lin, Zhiqing; Zakin, Jacques L

    2009-09-01

    Drag-reducing surfactant solutions are very sensitive to shear. Shear can induce nanostructural transitions which affect drag reduction effectiveness and rheological properties. Literature reports on the effects of shear on different micellar solutions are inconsistent. In this paper, the effects of shear on three cationic drag-reducing surfactant solutions each with very different nanostructures and rheological behaviors, Arquad 16-50/sodium salicylate (NaSal) (5 mM/5 mM) (has thread-like micelles, shear-induced structure and large first normal stress (N(1))), Arquad S-50/NaSal (5 mM/12.5 mM) (has branched micelles, no shear-induced structure and first normal stress is about zero) and Arquad 16-50/sodium 3,4-dimethyl-benzoate (5 mM/5 mM) (has vesicles and thread-like micelles, shear-induced structure and high first normal stress (N(1))) are studied by small-angle neutron scattering (SANS), together with their rheological properties, drag reduction behavior and nanostructures by cryogenic-temperature transmission electron microscopy(cryo-TEM). The differences in the rheological behavior and the SANS data of the solutions are explained by the different responses of the nanostructures to shear based on a two-step response to shear.

  3. Structure and interaction in protein solutions as studied by small-angle neutron scattering

    International Nuclear Information System (INIS)

    Chodankar, S.; Aswal, V.K.

    2005-01-01

    Small-angle neutron scattering (SANS) measurements have been performed to compare the effect of the salts KF, KCl, and KBr on crystallization in aqueous solution of lysozyme protein. It is found that the propensity of the salt to crystallize protein follows the Hoffmeister series (KF< KCl< KBr) with marked differences in the effect of these salts. In pure protein solution, lysozyme macromolecules are prolate ellipsoidal with semimajor and semiminor axes as 22 and 13.5 A, respectively. SANS also gives that the effective (structural+counterion) charge (Z) on the protein as obtained by taking into account screened Coulomb interaction between the protein macromolecules is found to be much smaller than the structural charge. There is decrease in Z suggesting the higher counterion condensation on protein with the increase in the concentration. The counterion condensation seems to be responsible for the differences in the effect of different salts. It is also found that with the addition of salts, lysozyme macromolecules convert to dimers, and for the same salt concentration the comparative effect of different salts follows the Hoffmeister series. Time evolved measurements prior to and after the crystallization show that the protein solution mostly consists of monomers and dimers. Interestingly, higher-mers are not observed in these measurements as perhaps they are formed in very small numbers towards the process that leads to the crystallization. The time dependent data have been used to obtain the fraction of crystallization as a function of time

  4. Comparison of micelle structure of glycolipids with different head groups by small angle neutron scattering

    International Nuclear Information System (INIS)

    He, Lizhong; Middelberg, Anton; Hartmann, Thorsten; Niemeyer, Bernd; Garamus, V.M.; Willumeit, Regine

    2005-01-01

    Full text: Glycolipids such as n-alkyl- beta-D-glucopyranoside and n-alkyl- beta-D-maltopyranoside can self-assemble into different structures depending on solution conditions. Their amphiphilic properties enable them to serve as biosurfactants in biology and biotechnology, especially for solubilizing membrane proteins. The physicochemical properties of glycolipids have attracted attentions from several research groups, aiming to better understand their application in biological and environmental processes. For example, small angle neutron and X-ray scattering have been used to study micelle structures formed by glycolipids. Our previous work has shown that n-octyl-beta- D-glucopyranoside and n-octyl- beta-D-maltopyranoside form micelles with different structure, suggesting an important role of the sugar head group in micelle formation. In the present work, we further compare micelle structures of n-octyl- beta-Dglucopyranoside and n-octyl- beta-D-galactopyranoside. These two glycolipids have the same hydrophobic tail and their head sugar groups differ only in the conformation with one hydroxyl group pointing to different direction. Our SANS data together with phase behaviours reported by other group have suggested that a slight alteration of head group conformation can significantly affect self-assembly of glycolipids. (authors)

  5. Small angle neutron scattering contrast variation reveals heterogeneities of interactions in protein gels.

    Science.gov (United States)

    Banc, A; Charbonneau, C; Dahesh, M; Appavou, M-S; Fu, Z; Morel, M-H; Ramos, L

    2016-06-28

    We propose a quantitative approach to probe the spatial heterogeneities of interactions in macromolecular gels, based on a combination of small angle X-ray (SAXS) and neutrons (SANS) scattering. We investigate the structure of model gluten protein gels and show that the gels display radically different SAXS and SANS profiles when the solvent is (at least partially) deuterated. The detailed analysis of the SANS signal as a function of the solvent deuteration demonstrates heterogeneities of sample deuteration at different length scales. The progressive exchange between the protons (H) of the proteins and the deuteriums (D) of the solvent is inhomogeneous and 60 nm large zones that are enriched in H are evidenced. In addition, at low protein concentration, in the sol state, solvent deuteration induces a liquid/liquid phase separation. Complementary biochemical and structure analyses show that the denser protein phase is more protonated and specifically enriched in glutenin, the polymeric fraction of gluten proteins. These findings suggest that the presence of H-rich zones in gluten gels would arise from the preferential interaction of glutenin polymers through a tight network of non-exchangeable intermolecular hydrogen bonds.

  6. Elucidation of spin echo small angle neutron scattering correlation functions through model studies.

    Science.gov (United States)

    Shew, Chwen-Yang; Chen, Wei-Ren

    2012-02-14

    Several single-modal Debye correlation functions to approximate part of the overall Debey correlation function of liquids are closely examined for elucidating their behavior in the corresponding spin echo small angle neutron scattering (SESANS) correlation functions. We find that the maximum length scale of a Debye correlation function is identical to that of its SESANS correlation function. For discrete Debye correlation functions, the peak of SESANS correlation function emerges at their first discrete point, whereas for continuous Debye correlation functions with greater width, the peak position shifts to a greater value. In both cases, the intensity and shape of the peak of the SESANS correlation function are determined by the width of the Debye correlation functions. Furthermore, we mimic the intramolecular and intermolecular Debye correlation functions of liquids composed of interacting particles based on a simple model to elucidate their competition in the SESANS correlation function. Our calculations show that the first local minimum of a SESANS correlation function can be negative and positive. By adjusting the spatial distribution of the intermolecular Debye function in the model, the calculated SESANS spectra exhibit the profile consistent with that of hard-sphere and sticky-hard-sphere liquids predicted by more sophisticated liquid state theory and computer simulation. © 2012 American Institute of Physics

  7. Small-angle neutron scattering study of structure and interaction of nanoparticle, protein, and surfactant complexes.

    Science.gov (United States)

    Mehan, Sumit; Chinchalikar, Akshay J; Kumar, Sugam; Aswal, Vinod K; Schweins, Ralf

    2013-09-10

    Small-angle neutron scattering (SANS) measurements have been carried out from the multicomponent system composed of Ludox HS40 silica nanoparticle, bovine serum albumin (BSA) protein, and sodium dodecyl sulfate (SDS) surfactant in an aqueous system under the solution condition that all the components are negatively charged. Although the components are similarly charged, strong structural evolutions among them have been observed. The complexes of different components in pairs (nanoparticle-protein, nanoparticle-surfactant, and protein-surfactant) have been examined to correlate the role of each component in the three-component nanoparticle-protein-surfactant system. The nanoparticle-protein system shows depletion interaction induced aggregation of nanoparticles in the presence of protein. Both nanoparticle and surfactant coexist individually in a nanoparticle-surfactant system. In the case of a protein-surfactant system, the cooperative binding of surfactant with protein leads to micelle-like clusters of surfactant formed along the unfolded protein chain. The structure of the three-component (nanoparticle-protein-surfactant) system is found to be governed by the synergetic effect of nanoparticle-protein and protein-surfactant interactions. The nanoparticle aggregates coexist with the structures of protein-surfactant complex in the three-component system. The nanoparticle aggregation as well as unfolding of protein is enhanced in this system as compared to the corresponding two-component systems.

  8. Growth of mesoporous silica nanoparticles monitored by time-resolved small-angle neutron scattering.

    Science.gov (United States)

    Hollamby, Martin J; Borisova, Dimitriya; Brown, Paul; Eastoe, Julian; Grillo, Isabelle; Shchukin, Dmitry

    2012-03-06

    Since the first development of surfactant-templated mesoporous silicas, the underlying mechanisms behind the formation of their structures have been under debate. Here, for the first time, time-resolved small-angle neutron scattering (tr-SANS) is applied to study the complete formation of mesoporous silica nanoparticles. A distinct advantage of this technique is the ability to detect contributions from the whole system, enabling the visualization not only of particle genesis and growth but also the concurrent changes to the coexistent micelle population. In addition, using contrast-matching tr-SANS, it is possible to highlight the individual contributions from the silica and surfactant. An analysis of the data agrees well with the previously proposed "current bun" model describing particle growth: Condensing silica oligomers adsorb to micelles, reducing intermicellar repulsion and resulting in aggregation to form initial particle nuclei. From this point, the growth occurs in a cooperative manner, with condensing silica filling the gaps between further aggregating micelles. The mechanistic results are discussed with respect to different reaction conditions by changing either the concentration of the silica precursor or the temperature. In doing so the importance of in situ techniques is highlighted, in particular, tr-SANS, for mechanism elucidation in the broad field of materials science.

  9. Small-angle neutron scattering modeling of spin disorder in nanoparticles.

    Science.gov (United States)

    Vivas, Laura G; Yanes, Rocio; Michels, Andreas

    2017-10-12

    Magnetic small-angle neutron scattering (SANS) is a powerful technique for investigating magnetic nanoparticle assemblies in nonmagnetic matrices. For such microstructures, the standard theory of magnetic SANS assumes uniformly magnetized nanoparticles (macrospin model). However, there exist many experimental and theoretical studies which suggest that this assumption is violated: deviations from ellipsoidal particle shape, crystalline defects, or the interplay between various magnetic interactions (exchange, magnetic anisotropy, magnetostatics, external field) may lead to nonuniform spin structures. Therefore, a theoretical framework of magnetic SANS of nanoparticles needs to be developed. Here, we report numerical micromagnetic simulations of the static spin structure and related unpolarized magnetic SANS of a single cobalt nanorod. While in the saturated state the magnetic SANS cross section is (as expected) determined by the particle form factor, significant deviations appear for nonsaturated states; specifically, at remanence, domain-wall and vortex states emerge which result in a magnetic SANS signal that is composed of all three magnetization Fourier components, giving rise to a complex angular anisotropy on a two-dimensional detector. The strength of the micromagnetic simulation methodology is the possibility to decompose the cross section into the individual Fourier components, which allows one to draw important conclusions regarding the fundamentals of magnetic SANS.

  10. Small angle neutron scattering study of polyelectrolyte brushes grafted to well-defined gold nanoparticle interfaces.

    Science.gov (United States)

    Jia, Haidong; Grillo, Isabelle; Titmuss, Simon

    2010-05-18

    Small angle neutron scattering (SANS) has been used to study the conformations, and response to added salt, of a polyelectrolyte layer grafted to the interfaces of well-defined gold nanoparticles. The polyelectrolyte layer is prepared at a constant coverage by grafting thiol-functionalized polystyrene (M(w) = 53k) to gold nanoparticles of well-defined interfacial curvature (R(c) = 26.5 nm) followed by a soft-sulfonation of 38% of the segments to sodium polystyrene sulfonate (NaPSS). The SANS profiles can be fit by Fermi-Dirac distributions that are consistent with a Gaussian distribution but are better described by a parabolic distribution plus an exponential tail, particularly in the high salt regime. These distributions are consistent with the predictions and measurements for osmotic and salted brushes at interfaces of low curvature. When the concentration of added salt exceeds the concentration of counterions inside the brush, there is a salt-induced deswelling, but even at the highest salt concentration the brush remains significantly swollen due to a short-ranged excluded volume interaction. This is responsible for the observed resistance to aggregation of these comparatively high concentration polyelectrolyte stabilized gold nanoparticle dispersions even in the presence of a high concentration of added salt.

  11. Nanoparticle charge control in nonpolar liquids: insights from small-angle neutron scattering and microelectrophoresis.

    Science.gov (United States)

    Kemp, Roger; Sanchez, Rodrigo; Mutch, Kevin J; Bartlett, Paul

    2010-05-18

    Electrostatic forces are typically produced in low polarity solvents by the addition of surfactants or charge-control additives. Although widely used, there is no consensus on the mechanism by which surfactants control the level of particle charge. We report an investigation using highly sensitive, single particle optical microelectrophoresis measurements combined with a small-angle neutron scattering study to establish the mechanism of charging by the surfactant AOT in the nonpolar solvent n-dodecane. We show that polymer-grafted particles with no chemically bound surface charges only charge above the critical micellar concentration of the surfactant. The surface potential increases gradually with increasing surfactant concentration c, before finally saturating at high c. The increase in the surface potential is correlated to the amount of surfactant adsorbed onto the surface of the particle. Using deuterated AOT and contrast variation techniques, we demonstrate that the surfactant is adsorbed within the polymer layer surrounding the particle core, probably as individual molecules rather than surfactant aggregates. A simple thermodynamic model accounts for the concentration dependence of the observed surface potential.

  12. Probing nanoparticle-macromolecule interaction and resultant structure by small-angle neutron scattering

    International Nuclear Information System (INIS)

    Aswal, V.K.

    2013-01-01

    Nanoparticles display unique and distinct characteristics from those of their constituent atoms and bulk materials which are being employed in numerous applications in the fields of medicine, electronics, optics, communications, energy, environment etc. Many of these applications require adjoining of nanoparticles with macromolecules such as proteins, polymers and surfactants to obtain functional objects. For example, nanoparticle-protein complexes are of great importance in controlling enzymatic behavior, targeted drug delivery and developing biocompatible materials. The nanoparticles interfaced with polymers are shown to be useful in developing protein sensor arrays. Interaction of surfactants with nanoparticles is utilized extensively for technical and industrial applications associated with colloidal stability, detergency and design of nanostructured functional interfaces. The interaction of two components, nanoparticles and macromolecule, strongly depends on the characteristics of both the nanoparticles (size, shape, surface roughness, charge density etc.) and macromolecules (type, charge, shape and solution conditions etc.) used. The interaction of macromolecule on nanoparticle surface is a cumulative effect of a number of forces such as electrostatic force, covalent bonding, hydrogen bonding, non-polar interaction, hydrophobic interactions etc. These interactions depending on the system conditions can lead to various structures. Small-angle neutron scattering (SANS) with the possibility to vary contrast is an ideal technique to study such multi-component systems. In this talk, some of our results of SANS from the complexes of nanoparticle-protein and nanoparticle surfactant systems will be discussed. (author)

  13. Use of small angle neutron scattering to study grain boundary cavitation

    International Nuclear Information System (INIS)

    Yang, M.; Weertman, J.R.; Roth, M.

    1984-01-01

    The technique of small angle neutron scattering can be used to obtain information on cavitation (e.g. void volume fractions, void size distributions, nucleation rates) which can scarcely be duplicated by other void measurement methods. Void size distribution curves for creep cavities in copper show that no voids are detectable below a cutoff radius which corresponds to the smallest stable void radius rsub(c) predicted by the equation rsub(c) = 2ν/σ. (Here ν is the surface energy and σ is the normal stress acting across the grain boundary). In contrast, most of the voids in copper fatigued under similar conditions (same temperature, stress amplitude equal to the creep stress) are far below this critical size. The average size of fatigue voids does not change appreciably with continued deformation whereas the average size of creep voids moves toward larger radii. There is no evidence for the existence of an incubation time associated with void nucleation. It is found that the void density is proportional to the creep time and therefore to the creep strain. (author)

  14. Small-angle neutron scattering and rheological analyses of nanoemulsion for cosmetics

    International Nuclear Information System (INIS)

    Kume, Takuji

    2014-01-01

    A stable nanoemulsion consisting of nanometer-sized oil droplets in water having a self-standing capability was prepared by high-pressure emulsification. Rheological measurements show that the nanoemulsion has a high viscosity and a yield stress. Small-angle neutron scattering (SANS) revealed the presence of an ordered crystal-like lattice structure in addition to spherical domains with a diameter of ca. 30 nm. Nonfluidity of nanoemulsion is ascribed to crystal-like lattice structure of nanodroplets. A mixed solution of 2-hydroxyethyl cellulose and the nanoemulsion has shear-thickening behavior (shear-induced gelation). Real-time SANS measurements with a Couette geometry as a function of shear rate (Rheo-SANS) revealed that a possible mechanism of gelation was proposed from the viewpoint of shear-induced percolation transition. Furthermore, mixtures of the nanoemulsion and poly(acrylic acid) solutions were opaque and kept the same interdomain distance and high viscosity. We estimated that it had phase-separated structure between nanoemulsion phase and poly(acrylic acid) solution phase. (author)

  15. Exciting Science being done on the CG-2 Small Angle Neutron Scattering beam line at HFIR

    Science.gov (United States)

    Debeer-Schmitt, Lisa; Bailey, Kathy; Melnichenko, Yuri; Wignall, George; Littrell, Ken

    2010-03-01

    The small-angle neutron scattering (SANS) beam line, CG-2, has been in operation since 2007. CG-2 has been optimized so that structures from 0.5 to 200 nm can be thoroughly investigated. HFIR's cold source places the flux at CG-2 among the best in the world. Along with high flux, many varied sample environments can easily be integrated into the beam line which gives the user a versatile temperature range from 1.5 K to 1000K. In addition there are two cryomagents (horizontal 4.5 T and vertical 7 T), pressure cells and load frames available to users allowing for the availability of multiple configurations of experimental setups. Due to all the above equipment and the flux at CG-2, there have been many diverse and intriguing scientific developments. One such outcome is the study of flux- line lattices found in Type-II superconductors including the highly touted iron pnictides. Besides superconductors, other science studied on CG2 ranges from molecular self-assembly and interactions in complex fluids to phase separation, grain growth and orientation in metallurgical alloys.

  16. Have some large structures? Try small-angle neutron scattering (SANS)

    Science.gov (United States)

    Debeer-Schmitt, Lisa; Bailey, Kathy; He, Lilin; Wignall, George; Melnichenkov, Yuri; Littrell, Ken

    2011-03-01

    The small-angle neutron scattering (SANS) beam line, CG-2, has been in operation since 2007. CG-2 has been optimized so that structures from 0.5 to 200 nm can be thoroughly investigated. HFIR's cold source places the flux at CG-2 among the best in the world. Along with high flux, many varied sample environments can easily be integrated into the beam line which gives the user a versatile temperature range from 1.5 K to 1000 K. In addition there are two cryomagnets (horizontal 4.5 T and vertical 7 T), pressure cells and load frames available to users allowing for the availability of multiple configurations of experimental setups. Due to all the above equipment and the flux at CG-2, there have been many diverse and intriguing scientific developments. One such outcome is the study of flux-line lattices found in Type-II superconductors including the highly touted iron pnictides. Besides superconductors, other science studied on CG-2 ranges from molecular self-assembly and interactions in complex fluids to phase separation to grain growth and orientation in metallurgical alloys.

  17. Effects of pressure and temperature on pore structure of ceramic synthesized from rice husk: A small angle neutron scattering investigation

    International Nuclear Information System (INIS)

    Raut Dessai, R.; Desa, J.A.E.; Sen, D.; Mazumder, S.

    2013-01-01

    Highlights: ► A porous ceramic has been prepared from silica obtained from rice husk. ► The ceramic has a hierarchical pore structure from micrometric to nano-metric. ► Small Angle Neutron Scattering data indicate nano-pore connectivity to micro-pores. ► Pore morphology can be tuned by compaction pressure and sintering temperature. -- Abstract: Ceramic powder has been synthesized from rice husk as the source of silica. In order to probe the evolution of its hierarchical mesoscopic and microscopic porous structure, the ceramic powder was compacted at different pressures and was sintered at different temperatures. A glassy ceramic to crystalline transition under thermal treatment (up to 1000 °C) was revealed by X-ray diffraction. Existence of pores in two widely separated length scales was indicated by small angle neutron scattering with the smaller ones having mass fractal arrangement. Although no significant change in small pore structure under thermal effect was indicated, a significant modification of the same has been revealed by small angle neutron scattering at different compaction pressures. Connectivity between the pores was ascertained from scattering experiments on the ceramic compact impregnated with heavy water. Scanning electron microscopy shows the microstructure to undergo appreciable coalescence of micrometric ceramic particles for sintering temperature and pressure changes

  18. Porosity of the Marcellus Shale: A contrast matching small-angle neutron scattering study

    Science.gov (United States)

    Bahadur, Jitendra; Ruppert, Leslie F.; Pipich, Vitaliy; Sakurovs, Richard; Melnichenko, Yuri B.

    2018-01-01

    Neutron scattering techniques were used to determine the effect of mineral matter on the accessibility of water and toluene to pores in the Devonian Marcellus Shale. Three Marcellus Shale samples, representing quartz-rich, clay-rich, and carbonate-rich facies, were examined using contrast matching small-angle neutron scattering (CM-SANS) at ambient pressure and temperature. Contrast matching compositions of H2O, D2O and toluene, deuterated toluene were used to probe open and closed pores of these three shale samples. Results show that although the mean pore radius was approximately the same for all three samples, the fractal dimension of the quartz-rich sample was higher than for the clay-rich and carbonate-rich samples, indicating different pore size distributions among the samples. The number density of pores was highest in the clay-rich sample and lowest in the quartz-rich sample. Contrast matching with water and toluene mixtures shows that the accessibility of pores to water and toluene also varied among the samples. In general, water accessed approximately 70–80% of the larger pores (>80 nm radius) in all three samples. At smaller pore sizes (~5–80 nm radius), the fraction of accessible pores decreases. The lowest accessibility to both fluids is at pore throat size of ~25 nm radii with the quartz-rich sample exhibiting lower accessibility than the clay- and carbonate-rich samples. The mechanism for this behaviour is unclear, but because the mineralogy of the three samples varies, it is likely that the inaccessible pores in this size range are associated with organics and not a specific mineral within the samples. At even smaller pore sizes (~<2.5 nm radius), in all samples, the fraction of accessible pores to water increases again to approximately 70–80%. Accessibility to toluene generally follows that of water; however, in the smallest pores (~<2.5 nm radius), accessibility to toluene decreases, especially in the clay-rich sample which

  19. What can we learn about the lipid vesicle structure from the small angle neutron scattering experiment?

    International Nuclear Information System (INIS)

    Kiselev, M.A.; Zemlyanaya, E.V.; Aswal, V.K.; Neubert, R.H.H.

    2005-01-01

    Small angle neutron scattering (SANS) on the unilamellar vesicle populations (diameter of 500 and 1000 Armstrong) was used to characterize lipid vesicles from dimyristoylphosphatidylcholine (DMPC) in three phases (gel, ripple, and liquid). Parameters of vesicle populations and internal structure of the DMPC bilayer were characterized on the basis of the Separated Form Factor (SFF) model. Vesicle shape changes from about spherical in liquid phase to elliptical in ripple and gel phases for vesicles prepared via extrusion through pores with the diameter of 500 Armstrong. Parameters of the internal bilayer structure (membrane thickness, thickness of the hydrophobic core, hydration, and surface area of lipid molecule) were determined on the basis of the Hydrophobic-Hydrophilic (HH) approximation of neutron scattering length density across the bilayer ρ(x) and on the basis of the Step Function (SF) approximation of ρ(x). It was demonstrated in the framework of HH approximation that DMPC membrane thickness in the liquid phase (T = 30 deg C) depends on the membrane curvature. Vesicle population prepared via extrusion through pores with the diameter of 500 Armstrong is characterized by an average radius of 275.6 ± 0.5 Armstrong, polydispersity of 27%, membrane thickness of 47.8 ± 0.2 Armstrong, thickness of hydrophobic core of 20.5 ± 0.3 Armstrong, surface area per DMPC molecule of 61.0 ± 0.4 A 2 Armstrong, and the number of water molecules per DMPC molecule of 11.9 ± 0.3. Vesicles prepared via extrusion through pores with the diameter of 1000 Armstrong have a polydispersity of 48%, and a membrane thickness of 45.6 ± 0.2 Armstrong. SF approximation was used to describe the DMPC membrane structure in gel (T 10 deg C) and ripple (T = 20 deg C) phases. DMPC vesicles prepared via extrusion through 1000- Armstrong pores have a membrane thickness of 49.6 ± 0.5 Armstrong in the gel phase and 48.3 ± 0.6 Armstrong in the ripple phase. The dependence of the DMPC membrane

  20. 12-D-Hydroxyoctadecanoic acid organogels : a small angle neutron scattering study

    Science.gov (United States)

    Terech, P.

    1992-12-01

    An optically active fatty acid derivative, 12-D-hydroxyoctadecanoic acid, gives thermally reversible and plastic gels in a variety of organic solvents. The structural parameters of the fibrous aggregates constituting the gel network are obtained from small angle neutron scattering experiments. The cross-sectional shape can be either a rather monodisperse square or a very elongated rectangle dependent upon the solvent type and concentration. With gels in benzene, the cross-section is a square of 214Åside with ca. 40 molecules per angström length of rigid fibre. The monoclinic symmetry of the crystalline aggregates induces, on the one hand, the appropriate molecular arrangements for an infinite H-bonding sequence along the fibre axis and, on the other hand, the ability to develop ribbon-like structures. Un acide gras optiquement actif, l'acide D-hydroxyl-12 octadécanoïque, donne des gels thermiquement réversibles et plastiques dans une variété de solvants organiques. Les paramètres structuraux des agrégats fibrillaires qui constituent le réseau du gel sont déduit à partir d'expériences de diffusion de neutrons aux petits angles. La forme de la section-droite des fibres peut être soit carrée et relativement monodisperse, soit très rectangulaire selon le type de solvant et la concentration. Pour des gels dans le benzène, la section-droite est un carré de 214Åde côté avec environ 40 molécules par angström de longueur de fibre rigide. La symétrie monoclinique des agrégats cristallins de D-HOA conduit d'une part, aux arrangements moléculaires d'une séquence infinie de liaisons H le long de l'axe de la fibre et d'autre part, à la capacité de développer des structures en rubains.

  1. Industrial Uses of Neutron Scattering

    Science.gov (United States)

    Priesmeyer, Hans Georg

    Recent progress in neutron scattering for industrial purposes is reviewed. The relevant fields of interest are small-angle scattering, high-resolution diffraction, texture determination, reflectometry and radiography. Potential users are encouraged to address themselves to one of the neutron scattering centers given in the Appendix.

  2. Decoration of carbon nanotubes with metal nanoparticles by wet chemical method: a small-angle neutron scattering study.

    Science.gov (United States)

    Bahadur, J; Sen, D; Mazumder, S; Parkash, Jyoti; Sathiyamoorthy, D; Venugopalan, R

    2010-05-01

    Multi-wall carbon nanotubes have been synthesized by catalytic chemical vapour deposition method. Attempts have been made to decorate the walls of these nanotubes with various metal nanoparticles (Ni, Cu and Fe) after functionalizing the nanotubes walls by wet chemical method. Small-Angle Neutron Scattering data reveals chain cluster type morphology of the carbon nanotubes. Transmission electron microscopy, Energy dispersive analysis of X-rays and Small-Angle Neutron Scattering measurements show that decoration of nanotube walls by metallic nano-particles could be realized for Ni and Cu nano-particles. Further, wall decoration by nano-particles of Fe could not be achieved by wet chemical method due to strong agglomeration behavior of Fe nano-particles.

  3. Concept for a time-of-flight Small Angle Neutron Scattering instrument at the European Spallation Source

    Energy Technology Data Exchange (ETDEWEB)

    Jaksch, S. [ESS Design Update Programme – Germany, Forschungszentrum Jülich GmbH, Jülich (Germany); Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Forschungszentrum Jülich GmbH, Garching (Germany); Martin-Rodriguez, D. [ESS Design Update Programme – Germany, Forschungszentrum Jülich GmbH, Jülich (Germany); Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Forschungszentrum Jülich GmbH, Garching (Germany); Neutron Optics and Shielding Group, European Spallation Source AB, Lund (Sweden); Ostermann, A. [Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) at Heinz Maier-Leibnitz Zentrum, Technische Universität Muünchen, Garching (Germany); Jestin, J. [Laboratoire Léon Brillouin, LLB, CEA—Saclay, Gif sur Yvette cedex (France); Duarte Pinto, S.; Bouwman, W.G. [Faculty of Applied Sciences, Delft University of Technology, Delft (Netherlands); Uher, J. [Amsterdam Scientific Instruments, Amsterdam (Netherlands); Engels, R. [Zentralinstitut für Elektronik (ZEA-2), Forschungszentrum Jülich GmbH, Jülich (Germany); Frielinghaus, H. [ESS Design Update Programme – Germany, Forschungszentrum Jülich GmbH, Jülich (Germany); Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Forschungszentrum Jülich GmbH, Garching (Germany)

    2014-10-21

    A new Small Angle Neutron Scattering instrument is proposed for the European Spallation Source. The pulsed source requires a time-of-flight analysis of the gathered neutrons at the detector. The optimal instrument length is found to be rather large, which allows for a polarizer and a versatile collimation. The polarizer allows for studying magnetic samples and incoherent background subtraction. The wide collimation will host VSANS and SESANS options that increase the resolution of the instrument towards µm and tens of µm, respectively. Two 1 m{sup 2} area detectors will cover a large solid angle simultaneously. The expected gains for this new instrument will lie in the range between 20 and 36, depending on the assessment criteria, when compared to up-to-date reactor based instruments. This will open new perspectives for fast kinetics, weakly scattering samples, and multi-dimensional contrast variation studies.

  4. Structure of polymer micelles close to the solid interface. A grazing incidence small angle neutron scattering study.

    Science.gov (United States)

    Wolff, M; Magerl, A; Zabel, H

    2005-02-01

    Block copolymers are widely used in industry. For scientific interests their aqueous solutions offer a model system for the investigation of crystallisation as the macromolecules agglomerate for elevated concentrations into micelles, which crystallise when a critical volume fraction is reached. We report on grazing incidence small angle neutron scattering (GISANS) or near surface small angle neutron scattering (NS-SANS) as an experimental tool to investigate the micelle crystallisation close to interfaces with different chemical termination. We find that in general crystallization is suppressed at a repulsive surface and favoured at an attractive one. Furthermore we show that the crystallization close the interface can be controlled by the micelle stability, resulting from the different composition and length of the monomers. The effect of the interface is found more important for a high micelle stability, whereas for a low stability it is shadowed by adsorbed monomers.

  5. Structure of Co–Zn ferrite ferrofluid: A small angle neutron scattering ...

    Indian Academy of Sciences (India)

    This work is carried out under the UGC-DAE-CSR project No. 117. Authors are thankful to Professors K V Rao and L Belova, Tmfy-MSE, Royal Institute of. Technology, Sweden for EDX and SEM images facilities. References. [1] P Lindner and T Zemb, Neutron, X-ray and light scattering: Introduction to an inves- tigation tool ...

  6. Volume 15. Neutron scattering

    International Nuclear Information System (INIS)

    Kostorz, G.

    1979-01-01

    This volume of the Treatise on Materials Science and Technology shows how neutron scattering methods can be used to obtain important information on materials, by guiding the reader through the principles and describing recent applications. Materials scientists, but also solid state physicists, physical chemists, and metallurgists interested in this field, will find a completely referenced survey of the ''classical topics'' of neutron scattering and a more detailed presentation of methods and techniques that are more specifically related to materials science. After a brief review of the general principles in the first chapter, subsequent chapters concentrate on particular methods and problems. The techniques used in neutron crystallography are presented, and selected applications of nuclear and magnetic scattering are discussed. The measurement of phonons, their role in phase transformations, and their behavior in the presence of crystal defects are considered, and quasi-elastic scattering is given detailed treatment. The methods of small-angle scattering and diffuse scattering have been developed to a considerable perfection in recent years and are presented in detail. The structure and dynamics of hydrogen dissolved in metals and the conformation and dynamics of polymers are two outstanding subjects to which neutron scattering has contributed so much in recent years that separate chapters are devoted to covering these fields. Finally, the choice of the appropriate materials is also becoming increasingly crucial in the design and construction of neutron spectrometers. Therefore, the last chapter deals with special materials problems in neutron devices

  7. Static and quasi-elastic small angle neutron scattering on biocompatible ionic ferrofluids: magnetic and hydrodynamic interactions

    CERN Document Server

    Gazeau, F; Dubois, E; Perzynski, R

    2003-01-01

    We investigate the structure and dynamics of ionic magnetic fluids (MFs), based on ferrite nanoparticles, dispersed at pH approx 7 either in H sub 2 O or in D sub 2 O. Polarized and non-polarized static small angle neutron scattering (SANS) experiments in zero magnetic field allow us to study both the magnetic and the nuclear contributions to the neutron scattering. The magnetic interparticle attraction is probed separately from the global thermodynamic repulsion and compares well to direct magnetic susceptibility measurements. The magnetic interparticle correlation is in these fluid samples independent of the probed spatial scale. In contrast, a spatial dependence of the interparticle correlation is evidenced at large PHI by the nuclear structure factor. A model of magnetic interaction quantitatively explains the under-field anisotropy of the SANS nuclear contribution. In a quasi-elastic neutron spin-echo experiment, we probe the Brownian dynamics of translation of the nanoparticles in the range 1.3 sup<=...

  8. Dynamics of field-induced ordering processes in ferrofluids studied by polarised small-angle neutron scattering

    International Nuclear Information System (INIS)

    Wiedenmann, A.; Keiderling, U.; May, R.P.; Dewhurst, C.

    2006-01-01

    The relaxation of the local ordering of nanoparticles induced by an external magnetic field in a concentrated Cobalt ferrofluid was studied by stroboscopic polarised small-angle neutron scattering. Magnetic and nuclear correlations were found to decay exponentially within a characteristic time of few seconds. The local hexagonal particle arrangements with aligned moments transform gradually to uncorrelated segments of dipolar chains. The dynamics is influenced by dipole-dipole interactions

  9. Small-angle neutron scattering in F.C.C. Fe-Ni and Fe-Ni-C alloys

    Energy Technology Data Exchange (ETDEWEB)

    Nadutov, V.M.; Svystunov, Y.O. [G.V. Kurdyumov Inst. for Metal Physics of the N.A.S. of Ukraine, Kyiv (Ukraine); Garamus, V.M.; Willumeit, R. [GKSS Research Centre, Geesthacht (Germany)

    2004-07-01

    Small-angle neutron scattering was studied in Invar Fe-Ni-C alloys in comparison with the Fe-Ni alloy. Moessbauer measurement was carried out to indicate magnetic structure. The nonlinear SANS curves were analysed using a power law function and the Porod approximation and interpreted in terms of aggregates characterized by smooth surfaces or fractal properties. The size and shape of the inhomogeneities were estimated by using the Indirect Fourier Transformation analysis. (orig.)

  10. Design and test of a reverse osmosis pressure cell for in-situ small-angle neutron scattering studies

    OpenAIRE

    Schwahn, Dietmar; Feilbach, Herbert; Starc, Thomas; Pipich, Vitaliy; Kasher, Roni; Oren, Yoram

    2017-01-01

    We introduce a new method for real-time studies of membrane scaling and biofouling on thin film composite membranes (TFC) in reverse osmosis and nanofiltration water treatment using in-situ small-angle neutron scattering (SANS). SANS delivers information on nano and microscopic structures that support the interpretation of relevant engineering parameters such as membrane permeability and water flux. A flow cell high pressure SANS is described, followed by SANS characterization of TFC membrane...

  11. Effect of crystal shape on neutron rocking curves of perfect single crystals designed for ultra-small-angle scattering experiments

    OpenAIRE

    Freund, A.K.; Rehm, C.

    2014-01-01

    The present study has been conducted in the framework of the channel-cut crystal design for the Kookaburra ultra-small-angle neutron scattering (USANS) instrument to be installed at the OPAL reactor of ANSTO. This facility is based on the classical Bonse-Hart method that uses two multiple-reflection crystal systems. The dynamical theory of diffraction by perfect crystals distinguishes two cases: the Darwin case applying to infinitely thick crystals and the Ewald solution for very small absorp...

  12. Small-angle neutron scattering investigations on sintering behavior in the powder compacts of ceria (CeO2)

    International Nuclear Information System (INIS)

    Bedekar, Vinila; Patra, A.K.; Sen, D.; Mazumder, S.; Tyagi, A.K.

    2008-01-01

    Nano-crystalline ceria powders have been synthesized by gel combustion process. The effect of sintering temperature on the pore morphology of the powder compacts has been investigated by small-angle neutron scattering (SANS) in the accessible scattering wave vector 'q' range of 0.003-0.17 nm -1 of a double crystal based instrument. The scattering profiles do not follow normal 'q -4 ' power law at higher q-values. The X-ray diffraction and light scattering results indicate that the ceria nano-powders are in the form of porous agglomerates. The porosity of the sintered compacts has been attributed to inter-agglomerate, inter-aggregate and intra-aggregate pores. Scattering profiles have been modeled by using a tri-modal size distribution of pores

  13. KWS-3, the new focusing-mirror ultra small-angle neutron scattering instrument and reflectometer at Juelich

    International Nuclear Information System (INIS)

    Kentzinger, E.; Dohmen, L.; Alefeld, B.; Ruecker, U.; Stellbrink, J.; Ioffe, A.; Richter, D.; Brueckel, Th.

    2004-01-01

    In Juelich, a new high-resolution small-angle neutron scattering (SANS) instrument and reflectometer has been built. The principle of this instrument is a one-to-one image of an entrance aperture on a 2D position-sensitive detector by neutron reflection on a double-focusing toroidal mirror. It permits to perform SANS studies with a scattering wave vector resolution between 10 -3 and 10 -4 A -1 with considerable intensity advantages over pinhole-SANS instruments. To date, KWS-3 is the worldwide unique SANS instrument running on this principle. We present here the characterization of the image produced by the mirror and a measurement of the scattering from a diffraction grating

  14. KWS-3, the new focusing-mirror ultra small-angle neutron scattering instrument and reflectometer at Jülich

    Science.gov (United States)

    Kentzinger, E.; Dohmen, L.; Alefeld, B.; Rücker, U.; Stellbrink, J.; Ioffe, A.; Richter, D.; Brückel, Th.

    2004-07-01

    In Jülich, a new high-resolution small-angle neutron scattering (SANS) instrument and reflectometer has been built. The principle of this instrument is a one-to-one image of an entrance aperture on a 2D position-sensitive detector by neutron reflection on a double-focusing toroidal mirror. It permits to perform SANS studies with a scattering wave vector resolution between 10-3 and 10-4Å-1 with considerable intensity advantages over pinhole-SANS instruments. To date, KWS-3 is the worldwide unique SANS instrument running on this principle. We present here the characterization of the image produced by the mirror and a measurement of the scattering from a diffraction grating.

  15. Structure of Co–Zn ferrite ferrofluid: A small angle neutron scattering

    Indian Academy of Sciences (India)

    A hydrothermal synthesis route is used to synthesize nanomagnetic particles of Co0.3Zn0.7Fe2O4 ferrite ferrofluids with particle diameter ranging from 5.5–9 nm. XRD analysis shows the formation of a single phase spinel structure. EDX results confirm the stoichiometric composition of the cations. Small angle neutron ...

  16. A Study of nuclear of interest martensitic steels and FeCr ODS alloys using small angle neutron scattering

    International Nuclear Information System (INIS)

    Mathon, Marie-Helene; De Carlan, Yann; Zhong, Shengyi; Klosek, Vincent; Ji, Vincent; Henry, Jean; Olier, Patrick

    2011-01-01

    Small Angle Neutron Scattering (SANS) technique allows to characterize at a nano-scale the microstructure of the ferritic martensitic steels and ODS FeCr alloys which are candidates for the internal structures of future nuclear reactors. Firstly, the microstructure evolution induced by neutron irradiation at high dose in conventional and Reduced Activation Fe9%Cr martensitic steels is presented. Then, a SANS study of Oxide Dispersion Strengthened (ODS) alloys is also presented. The main objective is to control the nano-size oxide particles at the various stages of the fabrication process. (authors)

  17. The effect of pressure, isotopic (H/D) substitution, and other variables on miscibility in polymer-solvent systems. The nature of the demixing process; dynamic light scattering and small angle neutron scattering studies. Final report

    International Nuclear Information System (INIS)

    Van Hook, W.A.

    2000-01-01

    A research program examining the effects of pressure, isotope substitution and other variables on miscibility in polymer solvent systems is described. The techniques employed included phase equilibrium measurements and dynamic light scattering and small angle neutron scattering

  18. Nanostructure in block copolymer solutions: Rheology and small-angle neutron scattering

    International Nuclear Information System (INIS)

    Habas, Jean-Pierre; Pavie, Emmanuel; Perreur, Christelle; Lapp, Alain; Peyrelasse, Jean

    2004-01-01

    Triblock copolymers composed of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) present an amphiphilic character in aqueous solutions. Since PPO is less hydrophilic than PEO and since their solubilities decrease when the temperature increases, the copolymers self-assemble spontaneously, forming micelles at moderate temperatures. For higher temperatures or concentrations, the copolymers or the micelles are ordered because of repulsive interactions and form lyotropic liquid crystalline phases. These are phases of very great viscosity with the aspect of gels, and transitions between different crystalline phases can occur at fixed concentration during an increase of temperature. We studied solutions of three different copolymers. The first two have a star structure. They are both composed of four branches (EO) x (PO) y fixed on an ethylene diamine, but differ by the values of x and y. Their commercial name is Tetronic 908 (x=114, y=21) and Tetronic 704 (x=16, y=18). The third copolymer (EO) 37 (PO) 56 (EO) 37 is linear and is known under the name of Pluronic P105. The measurements of the shear complex elastic modulus according to the temperature is used to determine the temperatures of the different transitions. Then, small-angle neutron scattering on samples under flow and true crystallographic arguments make it possible to identify the nature of the crystalline phases. For the systems studied, we show that the branched copolymers form only one type of liquid crystalline phase, which is bcc for the T908 and lamellar for the T704. For the linear copolymer, it is possible to identify three transitions: micellar solution to hexagonal phase, hexagonal phase to body-centered cubic phase, and finally body-centered cubic phase to lamellar phase

  19. Morphology of fast-tumbling bicelles: a small angle neutron scattering and NMR study.

    Science.gov (United States)

    Luchette, P A; Vetman, T N; Prosser, R S; Hancock, R E; Nieh, M P; Glinka, C J; Krueger, S; Katsaras, J

    2001-08-06

    Bilayered micelles, or bicelles, which consist of a mixture of long- and short-chain phospholipids, are a popular model membrane system. Depending on composition, concentration, and temperature, bicelle mixtures may adopt an isotropic phase or form an aligned phase in magnetic fields. Well-resolved (1)H NMR spectra are observed in the isotropic or so-called fast-tumbling bicelle phase, over the range of temperatures investigated (10-40 degrees C), for molar ratios of long-chain lipid to short-chain lipid between 0.20 and 1.0. Small angle neutron scattering data of this phase are consistent with the model in which bicelles were proposed to be disk-shaped. The experimentally determined dimensions are roughly consistent with the predictions of R.R. Vold and R.S. Prosser (J. Magn. Reson. B 113 (1996)). Differential paramagnetic shifts of head group resonances of dimyristoylphosphatidylcholine (DMPC) and dihexanoylphosphatidylcholine (DHPC), induced by the addition of Eu(3+), are also consistent with the bicelle model in which DHPC is believed to be primarily sequestered to bicelle rims. Selective irradiation of the DHPC aliphatic methyl resonances results in no detectable magnetization transfer to the corresponding DMPC methyl resonances (and vice versa) in bicelles, which also suggests that DHPC and DMPC are largely sequestered in the bicelle. Finally, (1)H spectra of the antibacterial peptide indolicidin (ILPWKWPWWPWRR-NH(2)) are compared, in a DPC micellar phase and the above fast-tumbling bicellar phases for a variety of compositions. The spectra exhibit adequate resolution and improved dispersion of amide and aromatic resonances in certain bicelle mixtures.

  20. Tensile Properties and Small-Angle Neutron Scattering Investigation of Stereoblock Elastomeric Polypropylene

    International Nuclear Information System (INIS)

    2002-01-01

    Elastomeric polypropylene (ePP) produced from unbridged 2-arylindene metallocene catalysts was studied by uniaxial tensile and small-angle neutron scattering (SANS) techniques. The ePP can be separated into three fractions by successive boiling-solvent fractionation method to yield: a low-tacticity fraction soluble in ether (ES), an intermediate-tacticity fraction soluble in heptane (HS), and a high-tacticity fraction insoluble in heptane (HI). Tensile properties of ePP were compared to its solvent fractions, and the role of each solvent fraction residing within ePP was investigated by blending 5 weight % deuterated fraction with ePP. The tensile properties of each fraction vary considerably, exhibiting properties from a weak gum elastomer for ES, to a semi-crystalline thermoplastic for HI. The intermediate-tacticity HS fraction exhibits elastic properties similar to the parent elastomer (ePP). In the melt at 160 C, SANS shows that all deuterated fractions are homogeneously mixed with ePP in a one-phase system. At 25 C upon a slow cooling from the melt, the low-tacticity fraction is preferentially segregated in the amorphous domains induced by different crystallization temperatures and kinetics of the deuterated ES and high-tacticity components. The high-tacticity component within ePP (dHI-ePP) retains its plastic properties in the blend. Despite its low crystallinity (∼ 2%), the low-tacticity fraction can co-crystallize with the crystalline matrix. The dES-ePP shows little or no relaxation when held under strain and recovers readily upon the release of stress

  1. Characterisation of nanovoiding in dental porcelain using small angle neutron scattering and transmission electron microscopy.

    Science.gov (United States)

    Lunt, Alexander; Terry, Ann; Ying, Siqi; Baimpas, Nikolaos; Sui, Tan; Kabra, Saurabh; Kelleher, Joe; King, Stephen; Khin, Neo Tee; Korsunsky, Alexander M

    2017-05-01

    Recent studies of the yttria partially stabilised zirconia-porcelain interface have revealed the presence of near-interface porcelain nanovoiding which reduces toughness and leads to component failure. One potential explanation for these nanoscale features is thermal creep which is induced by the combination of the residual stresses at the interface and sintering temperatures applied during manufacture. The present study provides improved understanding of this important phenomenon. Transmission electron microscopy and small angle neutron scattering were applied to a sample which was crept at 750°C and 100MPa (sample C), a second which was exposed to an identical heat treatment schedule in the absence of applied stress (sample H), and a reference sample in the as-machined state (sample A). The complementary insights provided by the two techniques were in good agreement and log-normal void size distributions were found in all samples. The void number density was found to be 1.61μm -2 , 25.4μm -2 and 98.6μm -2 in samples A, H and C respectively. The average void diameter in sample A (27.1nm) was found to be more than twice as large as in samples H (10.2nm) and C (11.6nm). The crept data showed the highest skewness parameter (2.35), indicating stress-induced growth of larger voids and void coalescence that has not been previously observed. The improved insight presented in this study can be integrated into existing models of dental prostheses in order to optimise manufacturing routes and thereby reduce the significant detrimental impact of this nanostructural phenomenon. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  2. Small-angle neutron scattering studies of hemoglobin confined inside silica tubes of varying sizes.

    Science.gov (United States)

    Mandal, Soumit S; Cristiglio, Viviana; Lindner, Peter; Bhattacharyya, Aninda J

    2014-02-03

    In addition to the chemical nature of the surface, the dimensions of the confining host exert a significant influence on confined protein structures; this results in immense biological implications, especially those concerning the enzymatic activities of the protein. This study probes the structure of hemoglobin (Hb), a model protein, confined inside silica tubes with pore diameters that vary by one order of magnitude (≈20-200 nm). The effect of confinement on the protein structure is probed by comparison with the structure of the protein in solution. Small-angle neutron scattering (SANS), which provides information on protein tertiary and quaternary structures, is employed to study the influence of the tube pore diameter on the structure and configuration of the confined protein in detail. Confinement significantly influences the structural stability of Hb and the structure depends on the Si-tube pore diameter. The high radius of gyration (Rg) and polydispersity of Hb in the 20 nm diameter Si-tube indicates that Hb undergoes a significant amount of aggregation. However, for Si-tube diameters greater or equal to 100 nm, the Rg of Hb is found to be in very close proximity to that obtained from the protein data bank (PDB) reported structure (Rg of native Hb=23.8 Å). This strongly indicates that the protein has a preference for the more native-like non-aggregated state if confined inside tubes of diameter greater or equal to 100 nm. Further insight into the Hb structure is obtained from the distance distribution function, p(r), and ab initio models calculated from the SANS patterns. These also suggest that the Si-tube size is a key parameter for protein stability and structure. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Structure and properties of aqueous methylcellulose gels by small-angle neutron scattering.

    Science.gov (United States)

    Chatterjee, Tirtha; Nakatani, Alan I; Adden, Roland; Brackhagen, Meinolf; Redwine, David; Shen, Hongwei; Li, Yongfu; Wilson, Tricia; Sammler, Robert L

    2012-10-08

    Cold, semidilute, aqueous solutions of methylcellulose (MC) are known to undergo thermoreversible gelation when warmed. This study focuses on two MC materials with much different gelation performance (gel temperature and hot gel modulus) even though they have similar metrics of their coarse-grained chemical structure (degree-of-methylether substitution and molecular weight distribution). Small-angle neutron scattering (SANS) experiments were conducted to probe the structure of the aqueous MC materials at pre- and postgel temperatures. One material (MC1, higher gel temperature) exhibited a single almost temperature-insensitive gel characteristic length scale (ζ(c) = 1090 ± 50 Å) at postgelation temperatures. This length scale is thought to be the gel blob size between network junctions. It also coincides with the length scale between entanglement sites measured with rheology studies at pregel temperatures. The other material (MC2, lower gel temperature) exhibited two distinct length scales at all temperatures. The larger length scale decreased as temperature increased. Its value (ζ(c1) = 1046 ± 19 Å) at the lowest pregel temperature was indistinguishable from that measured for MC1, and reached a limiting value (ζ(c1) = 450 ± 19 Å) at high temperature. The smaller length scale (ζ(c2) = 120 to 240 Å) increased slightly as temperature increased, but remained on the order of the chain persistence length (130 Å) measured at pregel temperatures. The smaller blob size (ζ(c1)) of MC2 suggests a higher bond energy or a stiffer connectivity between network junctions. Moreover, the number density of these blobs, at the same reduced temperature with respect to the gel temperature, is orders of magnitude higher for the MC2 gels. Presumably, the smaller gel length scale and higher number density lead to higher hot gel modulus for the low gel temperature material.

  4. Tensile Properties and Small-Angle Neutron Scattering Investigation of Stereoblock Elastomeric Polypropylene

    Energy Technology Data Exchange (ETDEWEB)

    Pople, John A

    2002-08-06

    Elastomeric polypropylene (ePP) produced from unbridged 2-arylindene metallocene catalysts was studied by uniaxial tensile and small-angle neutron scattering (SANS) techniques. The ePP can be separated into three fractions by successive boiling-solvent fractionation method to yield: a low-tacticity fraction soluble in ether (ES), an intermediate-tacticity fraction soluble in heptane (HS), and a high-tacticity fraction insoluble in heptane (HI). Tensile properties of ePP were compared to its solvent fractions, and the role of each solvent fraction residing within ePP was investigated by blending 5 weight % deuterated fraction with ePP. The tensile properties of each fraction vary considerably, exhibiting properties from a weak gum elastomer for ES, to a semi-crystalline thermoplastic for HI. The intermediate-tacticity HS fraction exhibits elastic properties similar to the parent elastomer (ePP). In the melt at 160 C, SANS shows that all deuterated fractions are homogeneously mixed with ePP in a one-phase system. At 25 C upon a slow cooling from the melt, the low-tacticity fraction is preferentially segregated in the amorphous domains induced by different crystallization temperatures and kinetics of the deuterated ES and high-tacticity components. The high-tacticity component within ePP (dHI-ePP) retains its plastic properties in the blend. Despite its low crystallinity ({le} 2%), the low-tacticity fraction can co-crystallize with the crystalline matrix. The dES-ePP shows little or no relaxation when held under strain and recovers readily upon the release of stress.

  5. Intracellular organisation of polyhydroxyalkanoate inclusion bodies: a role for small angle neutron scattering?

    International Nuclear Information System (INIS)

    Foster, L.J.R.; Holden, P.J.; Garvey, C.J.; Russell, R.A.; Stone, D.J.M.

    2003-01-01

    Full text: Polyhydroxyalkanoates (PHAs) are a diverse family of bacterially produced biopolyesters. Their biodegradability, and in some cases biocompatibility, suggest applications ranging from bioplastics to biomedical implantation devices. Despite extensive interest in their production and potential applications, little is known about their intracellular organisation. Microbial PHAs are synthesised by microorganisms under conditions of nutrient stress and can comprise up to 90% of the dry cell mass. The formation and organisation of these PHA inclusion bodies requires clarification. Such investigations have important implications for the biotechnological production of PHAs in microbes and other organisms, for downstream processing and in vitro precision polymerisation. Morphological and biochemical evidence supports two different models for the intracellular organisation of PHAs. Steinbuchel and coworkers propose a simple model of amorphous PHA enclosed by a single protein membrane consisting of structural proteins (PHAsins) and enzymes responsible for synthesis and degradation. In contrast, Fuller and coworkers have theorised a more complex system of PHA encompassed by a PHAsin bilayer separated by phospholipid. The polymerase and depolymerase enzymes are proposed to be associated with an incomplete inner PHAsin layer. It may be that such models are genera or species specific, since both proposals were derived from research on different species producing different types of PHA. Our initial investigations have focussed on in vivo deuteration of polyhydroxyoctanoate, produced by Pseudomonas oleovorans, both in fermentation on natural and deuterated substrates and during Small Angle Neutron Scattering by whole cells using AUSANS. The nature of the structural questions and our preliminary findings including contrast variation data will be discussed

  6. The use of magnetic small angle neutron scattering for the detection of flow profiles in magnetic fluids

    Energy Technology Data Exchange (ETDEWEB)

    Odenbach, S.; Gilly, H. [Center of Applied Spacetechnology and Microgravity (ZARM), University of Bremen, Am Fallturm, 28359 Bremen (Germany); Lindner, P. [Institute Laue Langevin, Avenue des Martyrs, BP 156, 38042 Grenoble Cedex (France)

    1999-07-01

    We have investigated the possibility of using magnetic small angle neutron scattering (MSANS) to detect the flow pattern of flow in concentrated magnetic fluids. It has been shown that the anisotropy of the scattering pattern can be determined with appropriate accuracy allowing to identify changes of the anisotropy induced by different flow states. These changes can be used as a measure for flow characteristics in the fluids. In this paper we present the general idea and an experimental demonstration of the concept using a simple convective flow pattern. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. Preparing Monodisperse Macromolecular Samples for Successful Biological Small-Angle X-ray and Neutron Scattering Experiments

    Science.gov (United States)

    Jeffries, Cy M.; Graewert, Melissa A.; Blanchet, Clément E.; Langley, David B.; Whitten, Andrew E.; Svergun, Dmitri I

    2017-01-01

    Small-angle X-ray and neutron scattering (SAXS and SANS) are techniques used to extract structural parameters and determine the overall structures and shapes of biological macromolecules, complexes and assemblies in solution. The scattering intensities measured from a sample contain contributions from all atoms within the illuminated sample volume including the solvent and buffer components as well as the macromolecules of interest. In order to obtain structural information, it is essential to prepare an exactly matched solvent blank so that background scattering contributions can be accurately subtracted from the sample scattering to obtain the net scattering from the macromolecules in the sample. In addition, sample heterogeneity caused by contaminants, aggregates, mismatched solvents, radiation damage or other factors can severely influence and complicate data analysis so it is essential that the samples are pure and monodisperse for the duration of the experiment. This Protocol outlines the basic physics of SAXS and SANS and reveals how the underlying conceptual principles of the techniques ultimately ‘translate’ into practical laboratory guidance for the production of samples of sufficiently high quality for scattering experiments. The procedure describes how to prepare and characterize protein and nucleic acid samples for both SAXS and SANS using gel electrophoresis, size exclusion chromatography and light scattering. Also included are procedures specific to X-rays (in-line size exclusion chromatography SAXS) and neutrons, specifically preparing samples for contrast matching/variation experiments and deuterium labeling of proteins. PMID:27711050

  8. Analysis of the nano-scale structure of a natural clayey soil using the small angle neutron scattering method

    International Nuclear Information System (INIS)

    Itakura, T.; Bertram, W.K.; Hathaway, P.V.; Knott, R.B.

    2001-01-01

    The small angle neutron scattering method (SANS) was used to analyze the nano-structure of a natural clayey soil used for containment of industrial liquid wastes. A Tertiary clay deposit called the Londonderry clay was used to contain the wastes in a state-run landfill facility in NSW. A number of site assessments have been carried out at the site and continual efforts have been made to characterize interactions between soil materials and contaminants at the site. Hence, it is of research and practical interest to investigate the effects of deformation on the nano-scale structure of the soil. Experiments have been conducted to analyze the structure of reconstituted clayey soil samples that were subjected to uniaxial compression ranging from 200 kPa to 800 kPa. The small angle neutron scattering instrument was used to measure the scattering intensity of these samples at a scattering vector (q) range between 0.01 and 0.1 Angstroms -1 . The sector integration technique was used to analyse elliptical scattering patterns along the major and minor axes. A relation between stress, void ratio and nano-scale structure properties was then briefly discussed for use in assessing the performance of clayey soils as in situ barriers

  9. Small-angle scattering on soft materials

    International Nuclear Information System (INIS)

    Mortensen, K.

    1994-01-01

    Small angle x-ray and neutron scattering provides tools for investigation of structures on the length scale 10 to 1000 A. This is the length scale which is relevant for many topics within soft materials, like biological macromolecules, polymers, colloids, etc. The very large difference between the scattering amplitude of neutrons by regular hydrogen and deuterium makes neutron scattering a very important technique within soft condensed matter. The basic theory for small angle scattering is reviewed. Experimental results obtained by small angle scattering are shown, with emphasis on soft materials. (author). 33 refs, 6 figs, 1 tab

  10. Numerical solution of the inverse problem in the analysis of neutron small angle scattering experiments

    International Nuclear Information System (INIS)

    Magnani, M.; Stefanon, M.; Puliti, P.

    1988-01-01

    A simple numerical procedure is presented to face particular problems encountered in the data analysis of small angle scattering studies of precipitation in complicated alloys. A suitable method for solving a least-squares problem with inequality constraints is suggested. (orig.)

  11. Undulations in salt-free charged lamellar phases detected by small angle neutron scattering and neutron reflectivity

    NARCIS (Netherlands)

    Salamat, G.; Vries, de R.; Kaler, E.W.; Satija, S.; Sung, L.

    2000-01-01

    Neutron reflectivity of lamellar phases containing pentaethylene glycol n-dodecyl ether, sodium decylsulfonate, and D2O is measured at the solid-liquid interface. The scattering length density profiles deduced from fits to the reflectivity data show that undulations of the mixed surfactant bilayers

  12. Small angle X-ray and neutron scattering from solutions of biological macromolecules

    CERN Document Server

    Svergun, Dmitri I; May, Roland P; Timmins, Peter A

    2013-01-01

    In this book, following the presentation of the basics of scattering from isotropic macromolecular solutions, modern instrumentation, experimental practice and advanced analysis techniques are explained. Advantages of X-rays (rapid data collection, small sample volumes) and of neutrons (contrast variation by hydrogen/deuterium exchange) are specifically highlighted. Examples of applications of the technique to different macromolecular systems are considered with specific emphasis on the synergistic use of SAXS/SANS with other structural, biophysical and computational techniques.

  13. On-going development on MINT's small angle neutron scattering (SANS) facility upgrading and related research activities

    International Nuclear Information System (INIS)

    Mohamed, Abdul Aziz Bin; Mohd, Shukri Bin; Muhammad, Azali Bin

    2003-01-01

    The TRIGA MARK II Research reactor at the Malaysian Institute for Nuclear Research (MINT) was commissioned in July 1982: next year will be its 20 year criticality. Since then various works have been performed to utilize the neutrons produced from this steady state reactor. Projects undertaken are the development and utilization of the Neutron Radiography (MyNR) and Small Angle Neutron Scattering (MySANS) facilities. Materials research, together with traditional scientific interest in understanding matter at the atomic scale, requires detail knowledge of the arrangement and the dynamics of the atoms or molecules. To enhance Malaysian research and development in this area in particular nanoparticle and nanostructure, MINT has made a dedicated commitment to strengthen the utilizing and maintaining the existing small angle neutron scattering facility to its optimal. This paper describes the recent progress of the MySANS facility and its proposed applications in materials science and technology research and education. Both management and technical strategies are generally explained. In addition a future work plan is also noted. (author)

  14. Structural Significance of Lipid Diversity as Studied by Small Angle Neutron and X-ray Scattering

    Directory of Open Access Journals (Sweden)

    Norbert Kučerka

    2015-09-01

    Full Text Available We review recent developments in the rapidly growing field of membrane biophysics, with a focus on the structural properties of single lipid bilayers determined by different scattering techniques, namely neutron and X-ray scattering. The need for accurate lipid structural properties is emphasized by the sometimes conflicting results found in the literature, even in the case of the most studied lipid bilayers. Increasingly, accurate and detailed structural models require more experimental data, such as those from contrast varied neutron scattering and X-ray scattering experiments that are jointly refined with molecular dynamics simulations. This experimental and computational approach produces robust bilayer structural parameters that enable insights, for example, into the interplay between collective membrane properties and its components (e.g., hydrocarbon chain length and unsaturation, and lipid headgroup composition. From model studies such as these, one is better able to appreciate how a real biological membrane can be tuned by balancing the contributions from the lipid’s different moieties (e.g., acyl chains, headgroups, backbones, etc..

  15. Structural Significance of Lipid Diversity as Studied by Small Angle Neutron and X-ray Scattering.

    Science.gov (United States)

    Kučerka, Norbert; Heberle, Frederick A; Pan, Jianjun; Katsaras, John

    2015-09-21

    We review recent developments in the rapidly growing field of membrane biophysics, with a focus on the structural properties of single lipid bilayers determined by different scattering techniques, namely neutron and X-ray scattering. The need for accurate lipid structural properties is emphasized by the sometimes conflicting results found in the literature, even in the case of the most studied lipid bilayers. Increasingly, accurate and detailed structural models require more experimental data, such as those from contrast varied neutron scattering and X-ray scattering experiments that are jointly refined with molecular dynamics simulations. This experimental and computational approach produces robust bilayer structural parameters that enable insights, for example, into the interplay between collective membrane properties and its components (e.g., hydrocarbon chain length and unsaturation, and lipid headgroup composition). From model studies such as these, one is better able to appreciate how a real biological membrane can be tuned by balancing the contributions from the lipid's different moieties (e.g., acyl chains, headgroups, backbones, etc.).

  16. Small angle neutron scattering study of nano sized microstructure in Fe-Cr ODS steels for gen IV in-core applications.

    Science.gov (United States)

    Han, Young-Soo; Mao, Xiadong; Jang, Jinsung

    2013-11-01

    The nano-sized microstructures in Fe-Cr oxide dispersion strengthened steel for Gen IV in-core applications were studied using small angle neutron scattering. The oxide dispersion strengthened steel was manufactured through hot isostatic pressing with various chemical compositions and fabrication conditions. Small angle neutron scattering experiments were performed using a 40 m small angle neutron scattering instrument at HANARO. Nano sized microstructures, namely, yttrium oxides and Cr-oxides were quantitatively analyzed by small angle neutron scattering. The yttrium oxides and Cr-oxides were also observed by transmission electron microscopy. The microstructural analysis results from small angle neutron scattering were compared with those obtained by transmission electron microscopy. The effects of the chemical compositions and fabrication conditions on the microstructure were investigated in relation to the quantitative microstructural analysis results obtained by small angle neutron scattering. The volume fraction of Y-oxide increases after fabrication, and this result is considered to be due to the formation of non-stochiometric Y-Ti-oxides.

  17. NANOSIZE STRUCTURE OF SELF-ASSEMBLY SODIUM DODECYL SULFATE: A STUDY BY SMALL ANGLE NEUTRON SCATTERING (SANS

    Directory of Open Access Journals (Sweden)

    Edy Giri Rachman Putra

    2010-06-01

    Full Text Available Small Angle Neutron Scattering (SANS investigation on the self-assembly sodium dodecyl sulfate (SDS molecules as a function of concentration and additives has been carried out. SANS spectrometer which has been completely installed at the neutron scattering laboratory (NSL BATAN in Serpong, Indonesia has played most important role to determine the growth (size and also the shapes of a micelle structure. In this works we report that spherical micelle structure with a radius of 16.7 Å will transform to ellipsoidal or rod-like micelle structure with the long axis extends up to 50 Å by increasing the concentration of SDS. Similar to that the micelle structures change by addition of salt in SDS micellar solutions.   Keywords: nanostructure, micelle, self-assembly

  18. In situ Electrochemical Small-Angle Neutron Scattering (eSANS) for Quantitative Structure and Redox Properties of Nanoparticles.

    Science.gov (United States)

    Prabhu, Vivek M; Reipa, Vytas

    2012-03-01

    The rapid growth in nanomaterial applications have revealed limitations in available physicochemical characterization methods. An in situ electrochemical small-angle neutron scattering (eSANS) methodology was devised that enables direct measurements of nanomaterial dispersion structure while undergoing reduction-oxidation (redox) reactions at the vitreous carbon electrode. Furthermore, these porous electrodes are amenable to contrast-variant neutron scattering strategies to measure nanoparticle structure and polymer conformation in multicomponent systems. The eSANS method was tested for feasibility by characterizing ZnO nanoparticles in 50 mmol/L NaCl deuterium oxide solution undergoing bulk electrolysis at negative potentials. Irreversible nanoparticle structural changes are observed during the potential cycle. The complete reduction of Zn(2+) to Zn(0) nanoparticles is unlikely, but a peak in the characteristic correlation length occurs during the redox bias with reduced average characteristic size.

  19. Quantifying "Softness" of Organic Coatings on Gold Nanoparticles Using Correlated Small-Angle X-ray and Neutron Scattering.

    Science.gov (United States)

    Diroll, Benjamin T; Weigandt, Katie M; Jishkariani, Davit; Cargnello, Matteo; Murphy, Ryan J; Hough, Lawrence A; Murray, Christopher B; Donnio, Bertrand

    2015-12-09

    Small-angle X-ray and neutron scattering provide powerful tools to selectively characterize the inorganic and organic components of hybrid nanomaterials. Using hydrophobic gold nanoparticles coated with several commercial and dendritic thiols, the size of the organic layer on the gold particles is shown to increase from 1.2 to 4.1 nm. A comparison between solid-state diffraction from self-assembled lattices of nanoparticles and the solution data from neutron scattering suggests that engineering softness/deformability in nanoparticle coatings is less straightforward than simply increasing the organic size. The "dendritic effect" in which higher generations yield increasingly compact molecules explains changes in the deformability of organic ligand shells.

  20. Fast, quantitative, and nondestructive evaluation of hydrided LWR fuel cladding by small angle incoherent neutron scattering of hydrogen

    Science.gov (United States)

    Yan, Y.; Qian, S.; Littrell, K.; Parish, C. M.; Plummer, L. K.

    2015-05-01

    A nondestructive neutron scattering method to precisely measure the uptake of hydrogen and the distribution of hydride precipitates in light water reactor (LWR) fuel cladding was developed. Zircaloy-4 cladding used in commercial LWRs was used to produce hydrided specimens. The hydriding apparatus consists of a closed stainless-steel vessel that contains Zr alloy specimens and hydrogen gas. Following hydrogen charging, the hydrogen content of the hydrided specimens was measured using the vacuum hot extraction method, by which the samples with desired hydrogen concentrations were selected for the neutron study. Optical microscopy shows that our hydriding procedure results in uniform distribution of circumferential hydrides across the wall thickness. Small angle neutron incoherent scattering was performed in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Our study demonstrates that the hydrogen in commercial Zircaloy-4 cladding can be measured very accurately in minutes by this nondestructive method over a wide range of hydrogen concentrations from a very small amount (≈20 ppm) to over 1000 ppm. The hydrogen distribution in a tube sample was obtained by scaling the neutron scattering rate with a factor determined by a calibration process using standard, destructive direct chemical analysis methods on the specimens. This scale factor can be used in future tests with unknown hydrogen concentrations, thus providing a nondestructive method for determining absolute hydrogen concentrations.

  1. Small angle neutron scattering modeling of copper-rich precipitates in steel

    International Nuclear Information System (INIS)

    The magnetic to nuclear scattering intensity ratio observed in the scattering from copper rich precipitates in irradiated pressure vessel steels is much smaller than the value of 11.4 expected for a pure copper precipitate in iron. A model for precipitates in pressure vessel steels which matches the observed scattering typically incorporates manganese, nickel, silicon and other elements and it is assumed that the precipitate is non-magnetic. In the present work consideration is given to the effect of composition gradients and ferromagnetic penetration into the precipitate on the small angle scattering cross section for copper rich clusters as distinguished from conventional precipitates. The calculation is an extension of a scattering model for micelles which consist of shells of varying scattering density. A discrepancy between recent SANS scattering experiments on pressure vessel steels was found to be related to applied magnetic field strength. The assumption of cluster structure and its relation to atom probe FIM findings as well as the effects of insufficient field for magnetic saturation is discussed

  2. Investigation of growth in post electron irradiated Al-11.8 at% Zn alloy by small angle neutron scattering

    International Nuclear Information System (INIS)

    Baig, M.R.

    1996-01-01

    The samples of Al-11.8 at% Zn alloy were irradiated with 2 Mev electrons at a flux of 10 4 electrons/cm 2 -s for different periods of time. The small angle neutron scattering (SANS) experiments were performed on unirradiated and irradiated samples under identical conditions. The results were obtained in the form of differential scattering cross section, versus momentum transfer vector Q(A 0-1 ). In general, results indicate an initial large drop in the magnitude of peak scattering cross section, increase in the precipitate size and reduction in the number density of the precipitates. More significant changes in these parameters have been noticed as the dose is increased. However, no such changes have been observed in the repeated measurements of post irradiated room temperature aged samples. We thus conclude that the changes induced by irradiation are found to be stable, and the small angle neutron scattering results are reproducible. It is thus concluded that there is an absence of growth in post irradiated room temperature aged Al-Zn alloy. (Author)

  3. Neutron scattering. Lectures

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2010-07-01

    The following topics are dealt with: Neutron sources, neutron properties and elastic scattering, correlation functions measured by scattering experiments, symmetry of crystals, applications of neutron scattering, polarized-neutron scattering and polarization analysis, structural analysis, magnetic and lattice excitation studied by inelastic neutron scattering, macromolecules and self-assembly, dynamics of macromolecules, correlated electrons in complex transition-metal oxides, surfaces, interfaces, and thin films investigated by neutron reflectometry, nanomagnetism. (HSI)

  4. Neutron scattering. Lectures

    International Nuclear Information System (INIS)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner

    2010-01-01

    The following topics are dealt with: Neutron sources, neutron properties and elastic scattering, correlation functions measured by scattering experiments, symmetry of crystals, applications of neutron scattering, polarized-neutron scattering and polarization analysis, structural analysis, magnetic and lattice excitation studied by inelastic neutron scattering, macromolecules and self-assembly, dynamics of macromolecules, correlated electrons in complex transition-metal oxides, surfaces, interfaces, and thin films investigated by neutron reflectometry, nanomagnetism. (HSI)

  5. Microstructural investigations of materials for low temperature co-fired ceramic (LTCC) based fuel cell using small angle neutron scattering

    Science.gov (United States)

    Mohamed, A. A.; Ahmad, M. H.; Ibrahim, A.; Azman, A.; Alias, R.; Ambak, Z.; Shapee, S.; Putra, E. G.; Patriati, A.; Sharom, M. A.; Yazid, H.; Mamat, M. R.; Karim, J. A.; Idris, F. M.; Yazid, K.; Zin, M. R.

    2013-06-01

    The concept and the realization fuel cell based on LTCC technology require the investigations of fired LTCC microstructures. The majority of the works involved using small angle neutron scattering studies on the microstructural of LTCC ceramic tape and development of neutron tomography for future tool to visualize channels inside the fired tape. Most SANS characterization were carried out at Smarter SANS instrument at BATAN, Indonesia. Standard sample for resolving tens of micron of object size were measured using simple neutron tomography setup utilizing monochromatic SANS beam at Malaysian Nuclear Agency. The initial microstructural findings indicates that organic additives shape the final microstructural of LTCC after firing with the glassy material possibly fill the space left by the burned organic additives. The tomography results showed that 40 micron size object can be differentiated. The conductor deposited on LTCC is preliminary investigated which will later be used as support for catalyst.

  6. Microstructural investigations of materials for low temperature co-fired ceramic (LTCC) based fuel cell using small angle neutron scattering

    International Nuclear Information System (INIS)

    Mohamed, A A; Yazid, K; Ahmad, M H; Azman, A; Yazid, H; Mamat, M R; Karim, J A; Idris, F M; Zin, M R; Ibrahim, A; Alias, R; Ambak, Z; Shapee, S; Putra, E G; Patriati, A; Sharom, M A

    2013-01-01

    The concept and the realization fuel cell based on LTCC technology require the investigations of fired LTCC microstructures. The majority of the works involved using small angle neutron scattering studies on the microstructural of LTCC ceramic tape and development of neutron tomography for future tool to visualize channels inside the fired tape. Most SANS characterization were carried out at Smarter SANS instrument at BATAN, Indonesia. Standard sample for resolving tens of micron of object size were measured using simple neutron tomography setup utilizing monochromatic SANS beam at Malaysian Nuclear Agency. The initial microstructural findings indicates that organic additives shape the final microstructural of LTCC after firing with the glassy material possibly fill the space left by the burned organic additives. The tomography results showed that 40 micron size object can be differentiated. The conductor deposited on LTCC is preliminary investigated which will later be used as support for catalyst.

  7. Magnetic-field-dependent small-angle neutron scattering on random anisotropy ferromagnets

    International Nuclear Information System (INIS)

    Michels, Andreas; Weissmueller, Joerg

    2008-01-01

    We report on the recently developed technique of magnetic-field-dependent small-angle neutron scattering (SANS), with attention to bulk ferromagnets exhibiting random magnetic anisotropy. In these materials, the various magnetic anisotropy fields (magnetocrystalline, magnetoelastic, and/or magnetostatic in origin) perturb the perfectly parallel spin alignment of the idealized ferromagnetic state. By varying the applied magnetic field, one can control one of the ordering terms which competes with the above-mentioned perturbing fields. Experiments which explore the ensuing reaction of the magnetization will therefore provide information not only on the field-dependent spin structure but, importantly, on the underlying magnetic interaction terms. This strategy, which underlies conventional studies of hysteresis loops in magnetometry, is here combined with magnetic SANS. While magnetometry generally records only a single scalar quantity, the integral magnetization, SANS provides access to a vastly richer data set, the Fourier spectrum of the response of the spin system as a function of the magnitude and orientation of the wave vector. The required data-analysis procedures have recently been established, and experiments on a number of magnetic materials, mostly nanocrystalline or nanocomposite metals, have been reported. Here, we summarize the theory of magnetic-field-dependent SANS along with the underlying description of random anisotropy magnets by micromagnetic theory. We review experiments which have explored the magnetic interaction parameters, the value of the exchange-stiffness constant as well as the Fourier components of the magnetic anisotropy field and of the magnetostatic stray field. A model-independent approach, based on the experimental autocorrelation function of the spin misalignment, provides access to the characteristic length of the spin misalignment. The field dependence of this quantity is in quantitative agreement with the predictions of

  8. SANS [small-angle neutron scattering] evaluation of the RPA [random phase approximation] theory for binary homopolymer mixtures

    International Nuclear Information System (INIS)

    Bates, F.S.; Koehler, W.C.; Wignall, G.D.; Fetters, L.J.

    1986-12-01

    A well characterized binary mixture of normal (protonated) and perdeuterated monodisperse 1,2 polybutenes has been studied by small-angle neutron scattering (SANS). For scattering wavevectors q greater than the inverse radius-of-gyration R/sub g/ -1 , the SANS intensity is quantitatively predicted by the random phase approximation (RPA) theory of deGennes over all measured values of the segment-segment interaction parameter Chi. In the region (Chi s-Chi)Chi s -1 > 0.5 the interaction parameter determined using the RPA theory for q > R/sub g/ -1 is greater than that calculated from the zero-angle intensity based on an Ornstein-Zernike plot, where Chi s represents the limit of single phase stability. These findings indicate a correlation between the critical fluctuation length ξ and R/sub g/ which is not accounted for by the RPA theory

  9. Structure and property characterization of low-k dielectric porous thin films determined by x-ray reflectivity and small-angle neutron scattering

    International Nuclear Information System (INIS)

    Lin, Eric K.; Lee, Hae-jeong; Wang, Howard; Wu Wenli

    2001-01-01

    A novel methodology using a combination of high energy ion scattering, x-ray reflectivity, and small angle neutron scattering is developed to characterize the structure and properties of porous thin films for use as low-k dielectric materials. Ion scattering is used to determine the elemental composition of the film. X-ray reflectivity is used to measure the average electron density, film thickness, and electron density depth profile. Small angle neutron scattering is used to determine the pore structure and pore connectivity. Combining information from all three techniques, the film porosity and matrix material density can be uniquely determined

  10. MAGNETIC NEUTRON SCATTERING

    International Nuclear Information System (INIS)

    ZALIZNYAK, I.A.; LEE, S.H.

    2004-01-01

    , ranging from large-scale structures and dynamics of polymers and biological systems, to electronic properties of today's technological materials. Neutron scattering developed into a vast field, encompassing many different experimental techniques aimed at exploring different aspects of matter's atomic structure and dynamics. Modern magnetic neutron scattering includes several specialized techniques designed for specific studies and/or particular classes of materials. Among these are magnetic reflectometry aimed at investigating surfaces, interfaces, and multilayers, small-angle scattering for the large-scale structures, such as a vortex lattice in a superconductor, and neutron spin-echo spectroscopy for glasses and polymers. Each of these techniques and many others offer exciting opportunities for examining magnetism and warrant extensive reviews, but the aim of this chapter is not to survey how different neutron-scattering methods are used to examine magnetic properties of different materials. Here, we concentrate on reviewing the basics of the magnetic neutron scattering, and on the recent developments in applying one of the oldest methods, the triple axis spectroscopy, that still is among the most extensively used ones. The developments discussed here are new and have not been coherently reviewed. Chapter 2 of this book reviews magnetic small-angle scattering, and modern techniques of neutron magnetic reflectometry are discussed in Chapter 3

  11. MAGNETIC NEUTRON SCATTERING

    Energy Technology Data Exchange (ETDEWEB)

    ZALIZNYAK,I.A.; LEE,S.H.

    2004-07-30

    science, ranging from large-scale structures and dynamics of polymers and biological systems, to electronic properties of today's technological materials. Neutron scattering developed into a vast field, encompassing many different experimental techniques aimed at exploring different aspects of matter's atomic structure and dynamics. Modern magnetic neutron scattering includes several specialized techniques designed for specific studies and/or particular classes of materials. Among these are magnetic reflectometry aimed at investigating surfaces, interfaces, and multilayers, small-angle scattering for the large-scale structures, such as a vortex lattice in a superconductor, and neutron spin-echo spectroscopy for glasses and polymers. Each of these techniques and many others offer exciting opportunities for examining magnetism and warrant extensive reviews, but the aim of this chapter is not to survey how different neutron-scattering methods are used to examine magnetic properties of different materials. Here, we concentrate on reviewing the basics of the magnetic neutron scattering, and on the recent developments in applying one of the oldest methods, the triple axis spectroscopy, that still is among the most extensively used ones. The developments discussed here are new and have not been coherently reviewed. Chapter 2 of this book reviews magnetic small-angle scattering, and modern techniques of neutron magnetic reflectometry are discussed in Chapter 3.

  12. Orientation and Relaxation of Polymer-clay Solutions Studied by Rheology and Small-angle Neutron Scattering

    International Nuclear Information System (INIS)

    Malwitz, M.M.; Butler, Paul D.; Porcar, L.; Angelette, D.P.; Schmidt, G.

    2004-01-01

    The influence of shear on viscoelastic solutions of poly(ethylene oxide) (PEO) and clay (montmorillonite, i.e., Cloisite NA+ (CNA)) was investigated with rheology and small-angle neutron scattering (SANS). The steady-state viscosity and SANS were used to measure the shear-induced orientation and relaxation of the polymer and clay platelets. Anisotropic scattering patterns developed at much lower shear rates than in pure clay solutions. The scattering anisotropy saturated at low shear rates, and the CNA clay platelets aligned with the flow, with the surface normal parallel to the gradient direction. The cessation of shear led to partial and slow randomization of the CNA platelets, whereas extremely fast relaxation was observed for laponite (LRD) platelets. These PEO-CNA networklike solutions were compared with previously reported PEO-LRD networks, and the differences and similarities, with respect to the shear orientation, relaxation, and polymer-clay interactions, were examined.

  13. The new 'BerSANS-PC' software for reduction and treatment of small angle neutron scattering data

    CERN Document Server

    Keiderling, U

    2002-01-01

    Measurements on small angle neutron scattering (SANS) instruments are typically characterized by a large number of samples, short measurement times for the individual samples, and a frequent change of visiting scientist groups. Besides this, recent advances in instrumentation have led to more frequent measurements of kinetic sequences and a growing interest in analyzing two-dimensional scattering data, these requiring special software tools that enable the users to extract physically relevant information from the scattering data with a minimum of effort. The new 'BerSANS-PC' data-processing software has been developed at the Hahn-Meitner-Institut (HMI) in Berlin, Germany, to meet these requirements and to support an efficiently working guest-user service. Comprising some basic functions of the 'BerSANS' program available at the HMI and other institutes in the past, BerSANS-PC is a completely new development for network-independent use on local PCs with a full-feature graphical interface. (orig.)

  14. Structures and interactions among globular proteins above the isoelectric point in the presence of divalent ions: A small angle neutron scattering and dynamic light scattering study

    Science.gov (United States)

    Kundu, Sarathi; Pandit, Subhankar; Abbas, Sohrab; Aswal, V. K.; Kohlbrecher, J.

    2018-02-01

    Small angle neutron scattering study reveals that at pD ≈ 7.0, above the isoelectric point of the globular protein Bovine Serum Albumin (BSA), in the presence of different divalent ions (Mg2+, Ca2+, Sr2+ and Ba2+), the short-range attractive interaction remains nearly constant and the intermediate-range repulsive interaction decreases with increasing salt concentration up to a certain concentration value but after that remains unchanged. However, for the monovalent ion (Na+), repulsive interaction decreases gradually up to 1 M salt concentration. Dynamic light scattering study shows that for all ions, diffusion coefficient of BSA decreases with increasing salt concentration and then nearly saturates.

  15. III International Conference on Small Angle Neutron Scattering dedicated to the 80 anniversary of Yu.M. Ostanevich

    International Nuclear Information System (INIS)

    2017-01-01

    Preface “Among the many well-known fundamental and applied consequences of neutron discovery, one of the first was the emergence of structural neutron diffraction - one of the methods for studying the spatial structure of condensed matter at the atomic level. Investigating the dynamics of biological macromolecules by neutron diffraction methods is an area that is almost untouched. We believe that also in this direction one should expect rapid progress.” Yu.M.Ostanevich and I.N.Serdyuk Uspekhi Fizicheskih Nauk (1982) More than 30 years after Ostanevich and Serdyuk reviewed the then 50 years from the neutron discovery, we are happy to support their statement and prediction by reporting on the further progress in the field of neutron scattering research. Frank Laboratory of Neutron Physics has organized the III International Conference on Small Angle Neutron Scattering (YuMO2016) that was – not coincidently – dedicated to the 80th anniversary of Ostanevich. Yuriy Mechislavovich Ostanevich (1936–1992) has had a determinative and crucial contribution to the construction of spectrometers at the pulsed reactor IBR in Dubna, Russia. He contributed in particular to the development of time-of-flight small-angle neutron scattering (SANS) technique, and the selection of advanced scientific areas for its application. The SANS instrument at the IBR-2 reactor is called YuMO in his honour. The Ostanevich’s leadership and outstanding scientific achievements in SANS studies of polyelectrolytes, small molecules, fractals, metallic glasses, macromolecules, polymers, etc., were recognized also by a number of awards including the State Prize of the Russian Federation in 2000. To this end of course, we should not forget mentioning the contribution of close collaborators of Ostanevich: Laszlo Cser, Josef Plestil as well as Alexander Kunchenko, Vadim Bezzabotnov and Nikolay Gorski. The YuMO2016 conference focused on providing opportunities to discuss various possibilities of

  16. Structure analyses of swollen rubber-filler systems by using contrast variation Small angle neutron scattering (SANS)

    International Nuclear Information System (INIS)

    Takenaka, Mikihito; Nishitsuji, Shotaro; Yamaguchi, Daisuke; Koizumi, Satoshi

    2009-01-01

    Full text: The polymer layers absorbed on silica particles in rubber-silica systems have investigated with contrast variation small-angle neutron scattering (SANS) method. The scattering intensities of specimens swollen by the solvents having various scattering length densities were measured. The contrast variation SANS for the specimens yielded partial scattering functions: the scattering function for polymer-polymer correlation SPP(q), the scattering function for silica- silica correlation SSS(q), and the scattering function for polymer- silica correlation SPS(q). The analyses of SSS(q) explored the hierarchical structures formed by silica particles. The analyses of SPS(q) and SSS(q) clarified the existence of dense polymer layers around silica aggregates. Several characteristic parameters are estimated from the analyses, such as the size of aggregates, the thickness of layers, the volume fractions of polymer of layers and matrix, and the correlation length of the matrix network. The contrast variation SANS is found to be a powerful tool of the analyses of the structures of the rubber-filler systems. (author)

  17. SMALL-ANGLE NEUTRON SCATTERING CONTRIBUTION TO DEVELOPMENT OF SOME NOVEL MATERIALS

    Czech Academy of Sciences Publication Activity Database

    Strunz, Pavel; Mukherji, D.; Petrenec, Martin; Gilles, R.; Schumacher, G.; Pigozzi, G.; Keiderling, U.; Geue, T.; Gasser, U.; Šaroun, Jan; Rösler, J.

    2013-01-01

    Roč. 20, č. 2 (2013), s. 67-69 ISSN 1211-5894. [Struktura 2013 - Kolokvium Krystalografické společnosti. Češkovice (Blansko), 09.09.2013-13.09.2013] R&D Projects: GA ČR(CZ) GAP204/11/1453; GA MŠk(XE) LM2011019 Institutional support: RVO:68081723 ; RVO:61389005 Keywords : neutron scattering * superalloy * temperature dependence Subject RIV: BM - Solid Matter Physics ; Magnetism; JL - Materials Fatigue, Friction Mechanics (UFM-A)

  18. Estimation of the solubility limit of Cr in Fe at 300 oC from small-angle neutron scattering in neutron-irradiated Fe-Cr alloys

    International Nuclear Information System (INIS)

    Bergner, F.; Ulbricht, A.; Heintze, C.

    2009-01-01

    The solubility limit of Cr in Fe (α-Fe-Cr) at low temperatures is a matter of debate. We report a direct estimation of the solubility limit at 300 o C from small-angle neutron scattering (SANS) data obtained for neutron-irradiated Fe-Cr alloys. The SANS results indicate that the equilibrium concentration of α' was reached via irradiation-enhanced diffusion. The solubility limit was estimated using an iterative approach based on the SANS invariant and the lever rule of phase equilibrium.

  19. A combined small-angle X-ray and neutron scattering study of the structure of purified soluble gastrointestinal mucins.

    Science.gov (United States)

    Georgiades, Pantelis; di Cola, Emanuela; Heenan, Richard K; Pudney, Paul D A; Thornton, David J; Waigh, Thomas A

    2014-12-01

    The structures of purified soluble porcine gastric (Muc5ac) and duodenal (Muc2) mucin solutions at neutral and acidic pH were examined using small-angle X-ray scattering and small-angle neutron scattering experiments. We provide evidence for the morphology of the network above the semidilute overlap concentration and above the entanglement concentration. Furthermore, we investigated the gelation of both types of mucin solutions in response to a reduction in pH, where we observed the formation of large-scale heterogeneities within the polymer solutions, typical of microphase-separated gels. The concentration dependence of the inhomogeneity length scale (Ξ) and the amplitude of the excess scattering intensity [I(ex) (0)] are consistent with previously studied gelled synthetic polymeric systems. The persistence lengths of the chains were found to be similar for both Muc5ac and Muc2 from Kratky plots of the neutron data (8 ± 2 nm). © 2014 Wiley Periodicals, Inc.

  20. Real-time small-angle neutron scattering techniques probing sub-millisecond dynamics in magnetic nanomaterials

    International Nuclear Information System (INIS)

    Wiedenmann, A.; Gaehler, R.; Dewhurst, C.; Keiderling, U.; Prevost, S.; Kohlbrecher, J.

    2010-01-01

    Stroboscopic Small Angle Neutron Scattering (SANS) techniques have recently been developed which allow ordering and relaxation processes of magnetic moments in nano-particles to be monitored. By applying a periodic external magnetic field the time-resolved SANS response to a forced oscillation could be analyzed. Here we present results from stroboscopic measurements on nanoscaled materials such as Cobalt ferrofluids and solid alloys by using polarised neutrons. SANS scattering response in an oscillating magnetic field was measured as a function of temperature, frequency and amplitude of the applied field. The fraction of superparamagnetic moments that can follow the oscillating field produces scattering patterns alternating between fully isotropic and strongly anisotropic. When the relaxation time of the ferrofluid to get in thermal equilibrium wit an applied magnetic field becomes similar to the period of the oscillating magnetic field one expects a phase shift and a damping in the magnetic response of the ferrofluid particles. To measure these polarized neutrons with polarisation analysis (POLARIS) are of great advantage

  1. Small-angle neutron scattering of multiwalled carbon nanotubes in aqueous suspensions in presence of laponite platelets or cetyltrimethylammonium bromide

    Directory of Open Access Journals (Sweden)

    L. A. Bulavin

    2013-12-01

    Full Text Available The results of small angle neutron scattering (SANS study of semidiluted 0.1 and 0.3 % wt aqueous suspensions of multiwalled carbon nanotubes (MWCNTs are reported. The additives of Laponite platelets or cationic surfactant cetyltrimethylammonium bromide (CTAB were used for enhancing the dispersion ability of MWCNTs. At high values of wave vector q, (1 nm-1 < q < 3.5 nm-1 all samples exhibited behavior characteristic for rigid rods (i.e., q-1 variation of neutron scattering intensity was observed. At low values of q (0.1 nm-1 < q < 0.5 nm-1, the neutron scattering intensity followed the power law q- with exponent the  in the range of 1.2 - 2, depending on concentration of the Laponite platelets or CTAB. Addition of Laponite platelets or CTAB allowed improvement of dispersion ability of MWCNTs. The effects were optimal at the certain value of Laponite/MWCNTs ratio X 0.5 or CTAB concentration (0.2 %wt. SANS also revealed existence of a mesh structure in MWCNT aggregates with characteristic mesh size of 7.4 nm and 6.3 nm in suspensions with concentration of 0.1 and 0.3 % wt of MWCNTs, respectively.

  2. Hierarchical architecture of bacterial cellulose and composite plant cell wall polysaccharide hydrogels using small angle neutron scattering.

    Science.gov (United States)

    Martínez-Sanz, Marta; Gidley, Michael J; Gilbert, Elliot P

    2016-02-07

    Small angle neutron scattering (SANS) has been applied to characterise the structure of pure bacterial cellulose hydrogels, and composites thereof, with two plant cell wall polysaccharides (arabinoxylan and xyloglucan). Conventional published models, which assume that bacterial cellulose ribbons are solid one-phase systems, fail to adequately describe the SANS data of pure bacterial cellulose. Fitting of the neutron scattering profiles instead suggests that the sub-structure of cellulose microfibrils contained within the ribbons results in the creation of regions with distinct values of neutron scattering length density, when the hydrogels are subjected to H2O/D2O exchange. This may be represented within a core-shell formalism that considers the cellulose ribbons to comprise a core containing impermeable crystallites surrounded by a network of paracrystalline cellulose and tightly bound water, and a shell containing only paracrystalline cellulose and water. Accordingly, a fitting function comprising the sum of a power-law term to account for the large scale structure of intertwined ribbons, plus a core-shell cylinder with polydisperse radius, has been applied; it is demonstrated to simultaneously describe all SANS contrast variation data of pure and composite bacterial cellulose hydrogels. In addition, the resultant fitting parameters indicate distinct interaction mechanisms of arabinoxylan and xyloglucan with cellulose, revealing the potential of this approach to investigate the role of different plant cell wall polysaccharides on the biosynthesis process of cellulose.

  3. Static and quasi-elastic small angle neutron scattering on biocompatible ionic ferrofluids: magnetic and hydrodynamic interactions

    International Nuclear Information System (INIS)

    Gazeau, F; Boue, F; Dubois, E; Perzynski, R

    2003-01-01

    We investigate the structure and dynamics of ionic magnetic fluids (MFs), based on ferrite nanoparticles, dispersed at pH ∼ 7 either in H 2 O or in D 2 O. Polarized and non-polarized static small angle neutron scattering (SANS) experiments in zero magnetic field allow us to study both the magnetic and the nuclear contributions to the neutron scattering. The magnetic interparticle attraction is probed separately from the global thermodynamic repulsion and compares well to direct magnetic susceptibility measurements. The magnetic interparticle correlation is in these fluid samples independent of the probed spatial scale. In contrast, a spatial dependence of the interparticle correlation is evidenced at large Φ by the nuclear structure factor. A model of magnetic interaction quantitatively explains the under-field anisotropy of the SANS nuclear contribution. In a quasi-elastic neutron spin-echo experiment, we probe the Brownian dynamics of translation of the nanoparticles in the range 1.3 ≤ qR g N ≤ 10 (q, scattering vector; R g N , nuclear radius of gyration of the nanoparticles). For the first time in an MF, we determine the hydrodynamic function at large q vectors

  4. Morphology of carbon nanotubes prepared via chemical vapour deposition technique using acetylene: a small angle neutron scattering investigation

    International Nuclear Information System (INIS)

    Sen, D.; Bahadur, J.; Mazumder, S.; Dasgupta, K.; Sathiyamoorthy, D.

    2008-01-01

    Small angle neutron scattering (SANS) has been utilized to study the morphology of the multi-walled carbon nanotubes prepared by chemical vapour deposition of acetylene. The effects of various synthesis parameters like temperature, catalyst concentration and catalyst support on the size distribution of the nanotubes are investigated. Distribution of nanotube radii in two length scales has been observed. The number density of the smaller diameter tubes was found more in number compared to the bigger one for all the cases studied. No prominent scaling of the structure factor was observed for the different synthesis conditions. (author)

  5. Microstructural characterization of dental zinc phosphate cements using combined small angle neutron scattering and microfocus X-ray computed tomography

    Czech Academy of Sciences Publication Activity Database

    Viani, Alberto; Sotiriadis, Konstantinos; Kumpová, Ivana; Mancini, L.; Appavou, M.-S.

    2017-01-01

    Roč. 33, č. 4 (2017), s. 402-417 ISSN 0109-5641 R&D Projects: GA MŠk(CZ) LO1219 Keywords : zinc phosphate cements * small angle neutron scattering * X-ray micro-computed tomography * X-ray powder diffraction * zinc oxide * acid-base cements Subject RIV: JJ - Other Materials OBOR OECD: Composites (including laminates, reinforced plastics, cermets, combined natural and synthetic fibre fabrics Impact factor: 4.070, year: 2016 https://www.sciencedirect.com/science/article/pii/S0109564116305127

  6. Study on microstructures of advanced metallic materials by small-angle X-ray and neutron scattering

    International Nuclear Information System (INIS)

    Ohnuma, Masato; Suzuki, Jun-ichi

    2006-01-01

    The microstructure of metal-nonmetal nano-granular soft magnetic films, precipitation hardened stainless steel and Al-Mg-Si alloys, have been studied by small-angle X-ray/neutron scattering (SAXS/SANS). Quantitative evaluation of average scale of their microstructures in nanometer scale has been accomplished by SAXS and SANS. Using this information, the contribution of the microstructures in nanometer scale has been accomplished by SAXS and SANS. Using this information, the contribution of the microstructures to the magnetic and mechanical properties are discussed in this paper. (author)

  7. Small-angle neutron scattering investigation of the chain conformation of lamellar polystyrene/isoprene phase in solid state

    International Nuclear Information System (INIS)

    Constantinescu, L.M.

    1994-01-01

    Small-angle neutron scattering has been used in the study of chain conformation of lamellar styrene/isoprene block copolymers oriented in large single crystals. The radius of gyration of deuterated polystyrene chains around the normal to the interface has been measured. By comparing this direct evolution of the lateral dimension of the chains with the average chain separation given by the molecular area (the surface available at the interface for each covalent bond linking the blocks together) we characterized the transverse interpenetration degree of the chains. The polystyrene chains are displayed in simple strata own micro-domains, without an important interpenetration. (Author) 9 Figs., 2 Tabs., 25 Refs

  8. Structure of the magnetite-oleic acid-decalin magnetic fluid from small-angle neutron scattering data

    Science.gov (United States)

    Nagornyi, A. V.; Petrenko, V. I.; Bulavin, L. A.; Avdeev, M. V.; Almásy, L.; Rosta, L.; Aksenov, V. L.

    2014-01-01

    Structural parameters of the magnetite-oleic acid-decalin magnetic fluid at various excesses of oleic acid (up to 25 vol %) have been determined using small-angle neutron scattering. Based on the comparison of the behavior of oleic acid in the magnetic fluid and in the pure solvent (decalin), it has been concluded that the interaction between the molecules of free (unadsorbed) surfactant changes in the presence of magnetic nanoparticles. However, the system remains stable and does not form aggregates of magnetic particles or free oleic acid. These results are compared with the previously presented data for similar benzene-based magnetic fluids.

  9. Determination of the spatial distribution of multiple fluid phases in porous media by ultra-small-angle neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Kainourgiakis, M.; Steriotis, Th. [National Center for Scientific Research ' Demokritos' , 15310 Ag. Paraskevi Attikis, Athens (Greece); Charalambopoulou, G., E-mail: gchar@chem.demokritos.gr [National Center for Scientific Research ' Demokritos' , 15310 Ag. Paraskevi Attikis, Athens (Greece); Strobl, M. [Helmholtz Zentrum Berlin fuer Materialien und Energie, Lise Meitner Campus, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Stubos, A. [National Center for Scientific Research ' Demokritos' , 15310 Ag. Paraskevi Attikis, Athens (Greece)

    2010-06-15

    In the present work contrast-matching USANS (ultra-small-angle neutron scattering) was employed in order to determine the spatial distribution of immiscible fluids confined within a macroporous {alpha}-Al{sub 2}O{sub 3} membrane. Water-air as well as water-hydrocarbon and hydrocarbon-air systems were examined and the analysis of the results, also on the basis of a complementary numerical study provided significant information on the behaviour of the multiphase ensemble as it has been demonstrated that the individual fluids occupy certain positions in the pore space, regardless of the actual values of the respective interfacial properties.

  10. Determination of the spatial distribution of multiple fluid phases in porous media by ultra-small-angle neutron scattering

    International Nuclear Information System (INIS)

    Kainourgiakis, M.; Steriotis, Th.; Charalambopoulou, G.; Strobl, M.; Stubos, A.

    2010-01-01

    In the present work contrast-matching USANS (ultra-small-angle neutron scattering) was employed in order to determine the spatial distribution of immiscible fluids confined within a macroporous α-Al 2 O 3 membrane. Water-air as well as water-hydrocarbon and hydrocarbon-air systems were examined and the analysis of the results, also on the basis of a complementary numerical study provided significant information on the behaviour of the multiphase ensemble as it has been demonstrated that the individual fluids occupy certain positions in the pore space, regardless of the actual values of the respective interfacial properties.

  11. Time-resolved small angle neutron scattering measurements of asphaltene nanoparticle aggregation kinetics in incompatible crude oil mixtures

    International Nuclear Information System (INIS)

    Mason, Thomas G.; Lin, Min Y.

    2003-01-01

    We use time-resolved-small angle neutron scattering to study the kinetics of asphaltene nanoparticle aggregation in incompatible crude oil mixtures. We induce asphaltene aggregation by mixing asphaltene-rich Syrian crude oil (SACO) with a paraffinic British crude oil and observe the scattered neutron intensity, I, as a function of wave number, q, over times, t, ranging from twenty minutes to about a week. We observe a growth in I at low q as the nanoscale asphaltenes agglomerate into microscale aggregates and interpret this growth as an increase in surface scattering from the aggregates. We fit I(q,t) to an empirical model and measure the growth in the power-law exponent, α, associated with the low-q logarithmic slope of I(q). We define a time, τ α , associated with the first appearance of the aggregates when α>3; τ α increases as a function of the volume fraction, φ m , of SACO in the mixture. The surface scattering intensity initially increases and then saturates at long times when the aggregate structures no longer evolve at the length scales we probe. Based on this saturation, we define a time scale, τ I , which is larger than τ α but has essentially the same dependence on φ m . We interpret τ α (φ m ) and τ I (φ m ) in terms of a simple aggregation model based on diffusion-limited kinetics and a repulsive potential barrier that models the effective solvent quality

  12. Porosity of silica Stöber particles determined by spin-echo small angle neutron scattering.

    Science.gov (United States)

    Parnell, S R; Washington, A L; Parnell, A J; Walsh, A; Dalgliesh, R M; Li, F; Hamilton, W A; Prevost, S; Fairclough, J P A; Pynn, R

    2016-05-25

    Stöber silica particles are used in a diverse range of applications. Despite their widespread industrial and scientific uses, information on the internal structure of the particles is non-trivial to obtain and is not often reported. In this work we have used spin-echo small angle neutron scattering (SESANS) in conjunction with ultra small angle X-ray scattering (USAXS) and pycnometry to study an aqueous dispersion of Stöber particles. Our results are in agreement with models which propose that Stöber particles have a porous core, with a significant fraction of the pores inaccessible to solvent. For samples prepared from the same master sample in a range of H2O : D2O ratio solutions we were able to model the SESANS results for the solution series assuming monodisperse, smooth surfaced spheres of radius 83 nm with an internal open pore volume fraction of 32% and a closed pore fraction of 10%. Our results are consistent with USAXS measurements. The protocol developed and discussed here shows that the SESANS technique is a powerful way to investigate particles much larger than those studied using conventional small angle scattering methods.

  13. Vacuum system upgrade for extended Q-range small-angle neutron scattering diffractometer (EQ-SANS) at SNS.

    Science.gov (United States)

    Stone, Christopher; Williams, Derrick; Price, Jeremy

    2016-01-01

    The Extended Q-range Small-angle Neutron Scattering Diffractometer (EQ-SANS) instrument at the spallation neutron source (SNS), Oak Ridge, Tennessee, incorporates a 69 m 3 detector vessel with a vacuum system which required an upgrade with respect to performance, ease of operation, and maintenance. The upgrade focused on improving pumping performance as well as optimizing system design to minimize opportunity for operational error. This upgrade provided the following practical contributions: •Reduced time required to evacuate from atmospheric pressure to 2 mTorr from 500 to 1000 min to 60-70 min•Provided turn-key automated control with a multi-faceted interlock for personnel and machine safety.

  14. X-ray magnetic circular dichroism and small angle neutron scattering studies of thiol capped gold nanoparticles

    International Nuclear Information System (INIS)

    de la Venta, J.; Bouzas, V.; Pucci, A.; Laguna-Marco, M.A.; Haskel, D.; te Velthuis, S.G.E; Hoffmann, A.; Lal, J.; Bleuel, M.; Ruggeri, G.; de Julian Fernandez, C.; Garcia, M.A.

    2009-01-01

    X-ray magnetic circular dichroism (XMCD) and Small Angle Neutron Scattering (SANS) measurements were performed on thiol capped Au nanoparticles (NPs) embedded into polyethylene. An XMCD signal of 0.8 · 10 -4 was found at the Au L 3 edge of thiol capped Au NPs embedded in a polyethylene matrix for which Superconducting Quantum Interference Device (SQUID) magnetometry yielded a saturation magnetization, M s , of 0.06 emu/g Au . SANS measurements showed that the 3.2 nm average-diameter nanoparticles are 28% polydispersed, but no detectable SANS magnetic signal was found with the resolution and sensitivity accessible with the neutron experiment. A comparison with previous experiments carried out on Au NPs and multilayers, yield to different values between XMCD signals and magnetization measured by SQUID magnetometer. We discuss the origin of those differences

  15. X-ray magnetic circular dichroism and small angle neutron scattering studies of thiol capped gold nanoparticles.

    Science.gov (United States)

    de la Venta, J; Bouzas, V; Pucci, A; Laguna-Marco, M A; Haskel, D; te Velthuis, S G E; Hoffmann, A; Lal, J; Bleuel, M; Ruggeri, G; de Julián Fernández, C; García, M A

    2009-11-01

    X-ray magnetic circular dichroism (XMCD) and Small Angle Neutron Scattering (SANS) measurements were performed on thiol capped Au nanoparticles (NPs) embedded into polyethylene. An XMCD signal of 0.8 x 10(-4) was found at the Au L3 edge of thiol capped Au NPs embedded in a polyethylene matrix for which Superconducting Quantum Interference Device (SQUID) magnetometry yielded a saturation magnetization, M(S), of 0.06 emu/g(Au). SANS measurements showed that the 3.2 nm average-diameter nanoparticles are 28% polydispersed, but no detectable SANS magnetic signal was found with the resolution and sensitivity accessible with the neutron experiment. A comparison with previous experiments carried out on Au NPs and multilayers, yield to different values between XMCD signals and magnetization measured by SQUID magnetometer. We discuss the origin of those differences.

  16. X-ray magnetic circular dichroism and small angle neutron scattering studies of thiol capped gold nanoparticles.

    Energy Technology Data Exchange (ETDEWEB)

    de la Venta, J.; Bouzas, V.; Pucci, A.; Laguna-Marco, M. A.; Haskel, D.; te Velthuis, S. G. E; Hoffmann, A.; Lal, J.; Bleuel, M.; Ruggeri, G.; de Julian Fernandez, C.; Garcia, M. A.; Univ.Complutense de Madrid; Inst. de Magnetismo Aplicado; Univ. of Pisa; Lab. di Magnetismo Molecolare

    2009-01-01

    X-ray magnetic circular dichroism (XMCD) and Small Angle Neutron Scattering (SANS) measurements were performed on thiol capped Au nanoparticles (NPs) embedded into polyethylene. An XMCD signal of 0.8 {center_dot} 10{sup -4} was found at the Au L{sub 3} edge of thiol capped Au NPs embedded in a polyethylene matrix for which Superconducting Quantum Interference Device (SQUID) magnetometry yielded a saturation magnetization, M{sub s}, of 0.06 emu/g{sub Au}. SANS measurements showed that the 3.2 nm average-diameter nanoparticles are 28% polydispersed, but no detectable SANS magnetic signal was found with the resolution and sensitivity accessible with the neutron experiment. A comparison with previous experiments carried out on Au NPs and multilayers, yield to different values between XMCD signals and magnetization measured by SQUID magnetometer. We discuss the origin of those differences.

  17. X-ray magnetic circular dichroism and small angle neutron scattering study of thiol capped gold nanoparticles.

    Energy Technology Data Exchange (ETDEWEB)

    de la Venta, J.; Bouzas, V.; Pucci, A.; Laguna-Marco, M. A.; Haskel, D.; Pinel, E. F.; te Velthuis, S. G. E.; Hoffmann, A.; Lal, J.; Bleuel, M.; Ruggeri, G.; de Julian, C.; Garcia, M. A.; Univ. Complutense de Madrid; Inst. de Magnetismo Aplicado UCM; Univ. Pisa; Univ. di Padova

    2009-11-01

    X-ray magnetic circular dichroism (XMCD) and Small Angle Neutron Scattering (SANS) measurements were performed on thiol capped Au nanoparticles (NPs) embedded into polyethylene. An XMCD signal of 0.8 {center_dot} 10{sup -4} was found at the Au L{sub 3} edge of thiol capped Au NPs embedded in a polyethylene matrix for which Superconducting Quantum Interference Device (SQUID) magnetometry yielded a saturation magnetization, M{sub s}, of 0.06 emu/g{sub Au}. SANS measurements showed that the 3.2 nm average-diameter nanoparticles are 28% polydispersed, but no detectable SANS magnetic signal was found with the resolution and sensitivity accessible with the neutron experiment. A comparison with previous experiments carried out on Au NPs and multilayers, yield to different values between XMCD signals and magnetization measured by SQUID magnetometer. We discuss the origin of those differences.

  18. The ultrastructure and flexibility of thylakoid membranes in leaves and isolated chloroplasts as revealed by small-angle neutron scattering.

    Science.gov (United States)

    Unnep, R; Zsiros, O; Solymosi, K; Kovács, L; Lambrev, P H; Tóth, T; Schweins, R; Posselt, D; Székely, N K; Rosta, L; Nagy, G; Garab, G

    2014-09-01

    We studied the periodicity of the multilamellar membrane system of granal chloroplasts in different isolated plant thylakoid membranes, using different suspension media, as well as on different detached leaves and isolated protoplasts-using small-angle neutron scattering. Freshly isolated thylakoid membranes suspended in isotonic or hypertonic media, containing sorbitol supplemented with cations, displayed Bragg peaks typically between 0.019 and 0.023Å(-1), corresponding to spatially and statistically averaged repeat distance values of about 275-330 Å⁻¹. Similar data obtained earlier led us in previous work to propose an origin from the periodicity of stroma thylakoid membranes. However, detached leaves, of eleven different species, infiltrated with or soaked in D2O in dim laboratory light or transpired with D2O prior to measurements, exhibited considerably smaller repeat distances, typically between 210 and 230 Å⁻¹, ruling out a stromal membrane origin. Similar values were obtained on isolated tobacco and spinach protoplasts. When NaCl was used as osmoticum, the Bragg peaks of isolated thylakoid membranes almost coincided with those in the same batch of leaves and the repeat distances were very close to the electron microscopically determined values in the grana. Although neutron scattering and electron microscopy yield somewhat different values, which is not fully understood, we can conclude that small-angle neutron scattering is a suitable technique to study the periodic organization of granal thylakoid membranes in intact leaves under physiological conditions and with a time resolution of minutes or shorter. We also show here, for the first time on leaves, that the periodicity of thylakoid membranes in situ responds dynamically to moderately strong illumination. This article is part of a special issue entitled: photosynthesis research for sustainability: keys to produce clean energy. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Power-law correlations and finite-size effects in silica particle aggregates studied by small-angle neutron scattering

    DEFF Research Database (Denmark)

    Freltoft, T.; Kjems, Jørgen; Sinha, S. K.

    1986-01-01

    Small-angle neutron scattering from normal, compressed, and water-suspended powders of aggregates of fine silica particles has been studied. The samples possessed average densities ranging from 0.008 to 0.45 g/cm3. Assuming power-law correlations between particles and a finite correlation length ξ......, the authors derive the scattering function S(q) from specific models for particle-particle correlation in these systems. S(q) was found to provide a satisfactory fit to the data for all samples studied. The fractal dimension df corresponding to the power-law correlation was 2.61±0.1 for all dry samples, and 2...

  20. The study of the structural properties of very low viscosity sodium alginate by small-angle neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Badita, C. R., E-mail: ramona@tandem.nipne.ro [Horia Hulubei National Institute of Physics and Nuclear Engineering, Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest, Romania, ramona@tandem.nipne.ro, daranghe@nipne.ro (Romania); University of Bucharest, Faculty of Physics, Atomiştilor 405, CP MG - 11, RO – 077125, Bucharest-Magurele (Romania); Aranghel, D., E-mail: daranghe@nipne.ro [Horia Hulubei National Institute of Physics and Nuclear Engineering, Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest, Romania, ramona@tandem.nipne.ro, daranghe@nipne.ro (Romania); Extreme Light Intrastructure Nuclear Physics (ELI-NP), Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest (Romania); Radulescu, A. [Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science, 85747 Garching (Germany); Anitas, E. M. [Horia Hulubei National Institute of Physics and Nuclear Engineering, Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest, Romania, ramona@tandem.nipne.ro, daranghe@nipne.ro (Romania); Joint Institute for Nuclear Research, 141980 Dubna, Moscow region (Russian Federation)

    2016-03-25

    Sodium alginate is a linear polymer extract from brown algae and it is used in the biomedical, food, cosmetics and pharmaceutical industries as solution property modifiers and gelling agents. But despite the extensive studies of the alginate gelation process, still some fundamental questions remain unresolved. The fractal behavior of very low viscosity sodium alginate solutions and their influence on the critical gelation of alginate induced by Ca{sup 2+} ions were investigated using Small-Angle Neutron Scattering (SANS) measurements. SANS data are interpreted using both standard linear plots and the Beaucage model. The scattering intensity is dependent by alginate concentration and Ca{sup 2+} concentration. From a critical concentration of 1.0 % w/w our polymer swelled forming spherical structures with rough surfaces. Also the addition of the salt induces the collapse and the appearance of the aggregation and clusters formation.

  1. The study of the structural properties of very low viscosity sodium alginate by small-angle neutron scattering

    International Nuclear Information System (INIS)

    Badita, C. R.; Aranghel, D.; Radulescu, A.; Anitas, E. M.

    2016-01-01

    Sodium alginate is a linear polymer extract from brown algae and it is used in the biomedical, food, cosmetics and pharmaceutical industries as solution property modifiers and gelling agents. But despite the extensive studies of the alginate gelation process, still some fundamental questions remain unresolved. The fractal behavior of very low viscosity sodium alginate solutions and their influence on the critical gelation of alginate induced by Ca 2+ ions were investigated using Small-Angle Neutron Scattering (SANS) measurements. SANS data are interpreted using both standard linear plots and the Beaucage model. The scattering intensity is dependent by alginate concentration and Ca 2+ concentration. From a critical concentration of 1.0 % w/w our polymer swelled forming spherical structures with rough surfaces. Also the addition of the salt induces the collapse and the appearance of the aggregation and clusters formation.

  2. The study of the structural properties of very low viscosity sodium alginate by small-angle neutron scattering

    Science.gov (United States)

    Badita, C. R.; Aranghel, D.; Radulescu, A.; Anitas, E. M.

    2016-03-01

    Sodium alginate is a linear polymer extract from brown algae and it is used in the biomedical, food, cosmetics and pharmaceutical industries as solution property modifiers and gelling agents. But despite the extensive studies of the alginate gelation process, still some fundamental questions remain unresolved. The fractal behavior of very low viscosity sodium alginate solutions and their influence on the critical gelation of alginate induced by Ca2+ ions were investigated using Small-Angle Neutron Scattering (SANS) measurements. SANS data are interpreted using both standard linear plots and the Beaucage model. The scattering intensity is dependent by alginate concentration and Ca2+ concentration. From a critical concentration of 1.0 % w/w our polymer swelled forming spherical structures with rough surfaces. Also the addition of the salt induces the collapse and the appearance of the aggregation and clusters formation.

  3. Characterization of Nano Sized Microstructures in Fe and Ni Base ODS Alloys Using Small Angle Neutron Scattering

    International Nuclear Information System (INIS)

    Han, Young-Soo; Jang, Jin-Sung; Mao, Xiaodong

    2015-01-01

    Ferritic ODS(Oxide-dispersion-strengthened) alloy is known as a primary candidate material of the cladding tubes of a sodium fast reactor (SFR) in the Generation IV research program. In ODS alloy, the major contribution to the enhanced high-temperature mechanical property comes from the existence of nano-sized oxide precipitates, which act as obstacles to the movement of dislocations. In addition for the extremely high temperature application(>950 .deg. C) of future nuclear system, Ni base ODS alloys are considered as candidate materials. Therefore the characterization of nano-sized microstructures is important for determining the mechanical properties of the material. Small angle neutron scattering (SANS) technique non-destructively probes structures in materials at the nano-meter length of scale (1 - 1000 nm) and has been a very powerful tool in a variety of scientific/engineering research areas. In this study, nano-sized microstructures were quantitatively analyzed by small angle neutron scattering. Quantitative microstructural information on nanosized oxide in ODS alloys was obtained from SANS data. The effects of the thermo mechanical treatment on the size and volume fraction of nano-sized oxides were analyzed. For 12Cr ODS alloy, the experimental A-ratio is two-times larger than the theoretical A-ratio., and this result is considered to be due to the imperfections included in YTaO 4 . For Ni base ODS alloy, the volume fraction of the mid-sized particles (- 30 nm) increases rapidly as hot extrusion temperature decreases

  4. Characterization of Nano Sized Microstructures in Fe and Ni Base ODS Alloys Using Small Angle Neutron Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Han, Young-Soo; Jang, Jin-Sung; Mao, Xiaodong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Ferritic ODS(Oxide-dispersion-strengthened) alloy is known as a primary candidate material of the cladding tubes of a sodium fast reactor (SFR) in the Generation IV research program. In ODS alloy, the major contribution to the enhanced high-temperature mechanical property comes from the existence of nano-sized oxide precipitates, which act as obstacles to the movement of dislocations. In addition for the extremely high temperature application(>950 .deg. C) of future nuclear system, Ni base ODS alloys are considered as candidate materials. Therefore the characterization of nano-sized microstructures is important for determining the mechanical properties of the material. Small angle neutron scattering (SANS) technique non-destructively probes structures in materials at the nano-meter length of scale (1 - 1000 nm) and has been a very powerful tool in a variety of scientific/engineering research areas. In this study, nano-sized microstructures were quantitatively analyzed by small angle neutron scattering. Quantitative microstructural information on nanosized oxide in ODS alloys was obtained from SANS data. The effects of the thermo mechanical treatment on the size and volume fraction of nano-sized oxides were analyzed. For 12Cr ODS alloy, the experimental A-ratio is two-times larger than the theoretical A-ratio., and this result is considered to be due to the imperfections included in YTaO{sub 4}. For Ni base ODS alloy, the volume fraction of the mid-sized particles (- 30 nm) increases rapidly as hot extrusion temperature decreases.

  5. Molecular conformation of the full-length tumor suppressor NF2/Merlin--a small-angle neutron scattering study.

    Science.gov (United States)

    Ali Khajeh, Jahan; Ju, Jeong Ho; Atchiba, Moussoubaou; Allaire, Marc; Stanley, Christopher; Heller, William T; Callaway, David J E; Bu, Zimei

    2014-07-29

    The tumor suppressor protein Merlin inhibits cell proliferation upon establishing cell-cell contacts. Because Merlin has high level of sequence similarity to the Ezrin-Radixin-Moesin family of proteins, the structural model of Ezrin-Radixin-Moesin protein autoinhibition and cycling between closed/resting and open/active conformational states is often employed to explain Merlin function. However, recent biochemical studies suggest alternative molecular models of Merlin function. Here, we have determined the low-resolution molecular structure and binding activity of Merlin and a Merlin(S518D) mutant that mimics the inactivating phosphorylation at S518 using small-angle neutron scattering and binding experiments. Small-angle neutron scattering shows that, in solution, both Merlin and Merlin(S518D) adopt a closed conformation, but binding experiments indicate that a significant fraction of either Merlin or Merlin(S518D) is capable of binding to the target protein NHERF1. Upon binding to the phosphatidylinositol 4,5-bisphosphate lipid, the wild-type Merlin adopts a more open conformation than in solution, but Merlin(S518D) remains in a closed conformation. This study supports a rheostat model of Merlin in NHERF1 binding and contributes to resolving a controversy about the molecular conformation and binding activity of Merlin. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Comparison of X-ray and neutron small-angle scattering from an Al-Zn alloy

    International Nuclear Information System (INIS)

    Gerold, V.; Epperson, J.E.; Gerstenberg, K.W.

    1978-01-01

    The normalized integrated small-angle scattered intensity for Al-Zn alloys should be independent of whether the measurements are made with X-rays or neutrons. In order to check this, and thus the correction and standardization processes, the small-angle scattering from an Al-5.05 at.% Zn alloy containing GP zones was measured with these two types of radiation. The data were corrected and converted to absolute units with reference to the commonly accepted secondary standards: vanadium for the neutron data and polyethylene (Lupolen) for the X-ray data. The results are shown to differ by, at best, 6% if reasonable values for the change in atomic volume with alloy composition are taken into account. These findings are compared with those available from the literature, and the consistency is found to be somewhat lacking. Additional careful work is clearly needed to determine if the difficulty is traceable to the data correction or to the conversion to absolute units. (Auth.)

  7. The use of small angle neutron scattering to measure the colloidal stability of magnetic nanoparticles intended for biomedical applications

    International Nuclear Information System (INIS)

    Connolly, J.; St Pierre, T.G.; Rutnakornpituk, M.; Riffle, J.S.

    2003-01-01

    The size and shape of particles in suspension and the interactions between the particles can be determined from small angle neutron scattering (SANS) studies. Magnetic cobalt nanoparticles have been manufactured with a view to using their unique properties for biomedical applications such as drug delivery and targetting to specific sites in the body. The nanoparticles are designed to form stable suspension and to remain isolated from one another in order to prevent formation of clusters of particles. The colloidal stability of the suspension is related to the size of the particles with larger particles being less stable than small ones in general. Electron microscopy images indicate that the cobalt nanoparticles form clusters but it is unclear if the clustering is an artifact of the specimen preparation. Small angle scattering experiments can determine if the aggregation observed on drying is the true behaviour of the nanoparticles while suspended in the carrier fluid. Cobalt nanoparticles and silica-coated cobalt nanoparticles were studied using SANS at the Australian Small Angle Neutron Scattering Facility (AUSANS) at the Australian Nuclear Science and Technology Organisation. Both sets of nanoparticles were coated in a silicon-based polymer and suspended in a silicon-based carrier fluid to form a stable dispersion. The SANS study points to the nanoparticles being fully dispersed and isolated when in the fluid state. Interactions between the particles may cause clustering over time. To study this, the SANS measurements were repeated after a 7 month interval. No significant changes in the particle sizes as measured by the SANS technique are observed indicating the suspensions of the particles are colloidally stable over time. Together these results indicate the nanoparticles may be candidates for biomedical applications

  8. Quality assessment of neutron delivery system for small-angle neutron scattering diffractometers of the Jülich Centre for Neutron Science at the FRM II

    International Nuclear Information System (INIS)

    Radulescu, Aurel; Pipich, Vitaliy; Ioffe, Alexander

    2012-01-01

    Following the shutdown of FRJ-2 research reactor in Jülich, the pinhole small-angle neutron diffractometers KWS-1 and KWS-2 have been moved to the research reactor FRM II in Garching. The installation of these 40 m long instruments required the design and setup of new neutron guides with geometrical and optical features imposed by the instruments' positioning in the neutron guide hall, such as, the predetermined length and beam height as well as the foreseen improvement of the instrument performance. We report here about the quality assessment of the newly constructed neutron guides with respect to the optical, geometrical and alignment characteristics and the positioning of the velocity selector integrated in the neutron guide system by comparing the features of the measured neutron beams (in terms of neutron flux, intensity distribution and beam profile) with the results of the simulations of optimal neutron guide systems.

  9. Effects of Macromolecular Crowding on an Intrinsically Disordered Protein Characterized by Small-Angle Neutron Scattering with Contrast Matching

    Science.gov (United States)

    Johansen, Daniel; Jeffries, Cy M.J.; Hammouda, Boualem; Trewhella, Jill; Goldenberg, David P.

    2011-01-01

    Small-angle neutron scattering was used to examine the effects of molecular crowding on an intrinsically disordered protein, the N protein of bacteriophage λ, in the presence of high concentrations of a small globular protein, bovine pancreatic trypsin inhibitor (BPTI). The N protein was labeled with deuterium, and the D2O concentration of the solvent was adjusted to eliminate the scattering contrast between the solvent and unlabeled BPTI, leaving only the scattering signal from the unfolded protein. The scattering profile observed in the absence of BPTI closely matched that predicted for an ensemble of random conformations. With BPTI added to a concentration of 65 mg/mL, there was a clear change in the scattering profile representing an increase in the mass fractal dimension of the unfolded protein, from 1.7 to 1.9, as expected if crowding favors more compact conformations. The crowding protein also inhibited aggregation of the unfolded protein. At 130 mg/mL BPTI, however, the fractal dimension was not significantly different from that measured at the lower concentration, contrary to the predictions of models that treat the unfolded conformations as convex particles. These results are reminiscent of the behavior of polymers in concentrated melts, suggesting that these synthetic mixtures may provide useful insights into the properties of unfolded proteins under crowding conditions. PMID:21320458

  10. A coarse graining approach to determine nucleic acid structures from small angle neutron scattering profiles in solution

    Science.gov (United States)

    Zhou, J.; Krueger, S.; Gregurick, S. K.

    2005-01-01

    We present a theoretical method to calculate the small angle neutron scattering profile of nucleic acid structures in solution. Our approach is sensitive to the sequence and the structure of the nucleic acid. In order to test our approach, we apply this method to the calculation of the experimental scattered intensity of the decamer d(CCAACGTTGG)2 in H2O. This sequence was specifically chosen for this study as it is believed to adopt a canonical B-form structure in 0.3 M NaCl. We find that not only will our methodology reproduce the experimental scattered intensity for this sequence, but our method will also discriminate between B-, A- and Z-form DNA. By studying the scattering profile of this structure in 0.5 and 1.0 M NaCl, we are also able to identify tetraplex and other similar oligomers formation and to model the complex using the experimental scattering data in conjunction with our methodology. PMID:16282586

  11. Designing and Performing Biological Solution Small-Angle Neutron Scattering Contrast Variation Experiments on Multi-component Assemblies.

    Science.gov (United States)

    Krueger, Susan

    2017-01-01

    Solution small-angle neutron scattering (SANS) combined with contrast variation provides information about the size and shape of individual components of a multi-component biological assembly, as well as the spatial arrangements between the components. The large difference in the neutron scattering properties between hydrogen and deuterium is key to the method. Isotopic substitution of deuterium for some or all of the hydrogen in either the molecule or the solvent can greatly alter the scattering properties of the biological assembly, often with little or no change to its biochemical properties. Thus, SANS with contrast variation provides unique information not easily obtained using other experimental techniques.If used correctly, SANS with contrast variation is a powerful tool for determining the solution structure of multi-component biological assemblies. This chapter discusses the principles of SANS theory that are important for contrast variation, essential considerations for experiment design and execution, and the proper approach to data analysis and structure modeling. As sample quality is extremely important for a successful contrast variation experiment, sample issues that can affect the outcome of the experiment are discussed as well as procedures used to verify the sample quality. The described methodology is focused on two-component biological complexes. However, examples of its use for multi-component assemblies are also discussed.

  12. Characterisation of large scale structures in starch granules via small-angle neutron and X-ray scattering.

    Science.gov (United States)

    Doutch, James; Gilbert, Elliot P

    2013-01-02

    Small angle scattering (SAS) techniques have a distinguished track record in illuminating the semi-crystalline lamellar structure of the starch granule. To date, there have been few attempts to use SAS techniques to characterise larger-scale structures reported from imaging techniques such as growth rings, blocklets or pores, nor how these structures would modulate the well-known scattering arising from the semi-crystalline lamellar structure. In this study, SAS data collected over an extended q range were gathered from dry and hydrated starch powders from varied botanical sources. The use of neutrons and X-rays, as well as comparing dry and hydrated granules, allowed different levels of contrast in scattering length density to be probed and therefore selected structural regions to be highlighted. The lowest q range, 0.002-0.04 Å(-1), was found to be dominated by scattering from the starch granules themselves, especially in the dry powders; however an inflection point from a low contrast structure was observed at 0.035 Å(-1). The associated scattering was interpreted within a unified scattering framework with the inflexion point correlating with a structure with radius of gyration ~90 Å - a size comparable to small blocklets or superhelices. In hydrated starches, it is observed that there is an inflection point between lamellar and q(-4) power-law scattering regions at approximately 0.004 Å(-1) which may correlate with growth rings and large blocklets. The implications of these findings on existing models of starch lamellar scattering are discussed. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  13. Neutron scattering

    International Nuclear Information System (INIS)

    Furrer, A.

    1993-01-01

    This report contains the text of 16 lectures given at the Summer School and the report on a panel discussion entitled ''the relative merits and complementarities of x-rays, synchrotron radiation, steady- and pulsed neutron sources''. figs., tabs., refs

  14. Neutron Scattering

    International Nuclear Information System (INIS)

    Fayer, Michael J.; Gee, Glendon W.

    2005-01-01

    The neutron probe is a standard tool for measuring soil water content. This article provides an overview of the underlying theory, describes the methodology for its calibration and use, discusses example applications, and identifies the safety issues. Soil water makes land-based life possible by satisfying plant water requirements, serving as a medium for nutrient movement to plant roots and nutrient cycling, and controlling the fate and transport of contaminants in the soil environment. Therefore, a successful understanding of the dynamics of plant growth, nutrient cycling, and contaminant behavior in the soil requires knowledge of the soil water content as well as its spatial and temporal variability. After more than 50 years, neutron probes remain the most reliable tool available for field monitoring of soil water content. Neutron probes provide integrated measurements over relatively large volumes of soil and, with proper access, allow for repeated sampling of the subsurface at the same locations. The limitations of neutron probes include costly and time-consuming manual operation, lack of data automation, and costly regulatory requirements. As more non-radioactive systems for soil water monitoring are developed to provide automated profiling capabilities, neutron-probe usage will likely decrease. Until then, neutron probes will continue to be a standard for reliable measurements of field water contents in soils around the globe

  15. Effect of crystal shape on neutron rocking curves of perfect single crystals designed for ultra-small-angle scattering experiments

    International Nuclear Information System (INIS)

    Freund, A K; Rehm, C

    2014-01-01

    The present study has been conducted in the framework of the channel-cut crystal design for the Kookaburra ultra-small-angle neutron scattering (USANS) instrument to be installed at the OPAL reactor of ANSTO. This facility is based on the classical Bonse-Hart method that uses two multiple-reflection crystal systems. The dynamical theory of diffraction by perfect crystals distinguishes two cases: the Darwin case applying to infinitely thick crystals and the Ewald solution for very small absorption taking into account the reflection from the rear face of a plane-parallel crystal reflecting in Bragg geometry. The former is preferable because it yields narrower rocking curves. To prevent the neutrons to 'see' the rear face, grooves were machined into the backside of perfect Si test crystals for single reflection and filled with neutron absorbing material. These samples were examined at the S18 instrument of the Institut Laue-Langevin. Unexpectedly the crystals with empty slots showed an increase of the rocking curve width. When filling the slots with an absorber the widths decreased, but without reaching that of the Darwin curve. Understanding the results and achieving a successful crystal design call for the development of a theory that permits to describe neutron diffraction from crystals with a structured back face.

  16. Effect of crystal shape on neutron rocking curves of perfect single crystals designed for ultra-small-angle scattering experiments

    Science.gov (United States)

    Freund, A. K.; Rehm, C.

    2014-07-01

    The present study has been conducted in the framework of the channel-cut crystal design for the Kookaburra ultra-small-angle neutron scattering (USANS) instrument to be installed at the OPAL reactor of ANSTO. This facility is based on the classical Bonse-Hart method that uses two multiple-reflection crystal systems. The dynamical theory of diffraction by perfect crystals distinguishes two cases: the Darwin case applying to infinitely thick crystals and the Ewald solution for very small absorption taking into account the reflection from the rear face of a plane-parallel crystal reflecting in Bragg geometry. The former is preferable because it yields narrower rocking curves. To prevent the neutrons to "see" the rear face, grooves were machined into the backside of perfect Si test crystals for single reflection and filled with neutron absorbing material. These samples were examined at the S18 instrument of the Institut Laue-Langevin. Unexpectedly the crystals with empty slots showed an increase of the rocking curve width. When filling the slots with an absorber the widths decreased, but without reaching that of the Darwin curve. Understanding the results and achieving a successful crystal design call for the development of a theory that permits to describe neutron diffraction from crystals with a structured back face.

  17. Quantitative analysis of inclusions in low carbon free cutting steel using small-angle X-ray and neutron scattering

    International Nuclear Information System (INIS)

    Oba, Yojiro; Koppoju, Suresh; Ohnuma, Masato; Kinjo, Yuki; Tomota, Yo; Morooka, Satoshi; Suzuki, Jun-ichi; Yamaguchi, Daisuke; Koizumi, Satoshi; Sato, Masugu; Shiraga, Tetsuo

    2012-01-01

    The microstructure of inclusions in low carbon free cutting steel without lead addition was investigated using small-angle X-ray scattering (SAXS) coupled with small-angle neutron scattering (SANS). The two-dimensional (2D) SAXS pattern shows clear scattering due to inclusions composed of large elongated particles aligned along the rolling direction, and small isotropic particles. From a comparison of the simulated and experimental 2D SAXS patterns, the shapes of the inclusions are regarded as ellipsoid for the larger inclusions and spherical for the smaller inclusions. The length of the minor axis in the large inclusion is 6.9 μm, while the diameter of the small inclusion is 0.50 μm. The aspect ratio of the large inclusion is estimated to be 3.8 in the lower q region, and is reduced slightly to 3.5 in the higher q region from the azimuthal plots. The results of an alloy contrast variation (ACV) analysis using both the SAXS and SANS data indicate that the chemical composition of the inclusions is almost NaCl-type manganese sulfide, and that the amount of iron sulfide is low. The volume fractions are 1.4% for the large inclusions and 0.2% for the small inclusions. This is consistent with the area fraction estimated using an optical microscope, and indicates that nearly all of the sulfur in the steel sample forms the manganese sulfide inclusions. (author)

  18. Minimal effects of macromolecular crowding on an intrinsically disordered protein: a small-angle neutron scattering study.

    Science.gov (United States)

    Goldenberg, David P; Argyle, Brian

    2014-02-18

    Small-angle neutron scattering was used to study the effects of macromolecular crowding by two globular proteins, i.e., bovine pancreatic trypsin inhibitor and equine metmyoglobin, on the conformational ensemble of an intrinsically disordered protein, the N protein of bacteriophage λ. The λ N protein was uniformly labeled with (2)H, and the concentrations of D2O in the samples were adjusted to match the neutron scattering contrast of the unlabeled crowding proteins, thereby masking their contribution to the scattering profiles. Scattering from the deuterated λ N was recorded for samples containing up to 0.12 g/mL bovine pancreatic trypsin inhibitor or 0.2 g/mL metmyoglobin. The radius of gyration of the uncrowded protein was estimated to be 30 Å and was found to be remarkably insensitive to the presence of crowders, varying by scattering profiles were also used to estimate the fractal dimension of λ N, which was found to be ∼1.8 in the absence or presence of crowders, indicative of a well-solvated and expanded random coil under all of the conditions examined. These results are contrary to the predictions of theoretical treatments and previous experimental studies demonstrating compaction of unfolded proteins by crowding with polymers such as dextran and Ficoll. A computational simulation suggests that some previous treatments may have overestimated the effective volumes of disordered proteins and the variation of these volumes within an ensemble. The apparent insensitivity of λ N to crowding may also be due in part to weak attractive interactions with the crowding proteins, which may compensate for the effects of steric exclusion. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  19. Neutron scattering studies on soft materials

    International Nuclear Information System (INIS)

    Inoue, Rintaro; Kanaya, Toshiji

    2010-01-01

    We review recent progress of neutron scattering studies on soft matters using various techniques such as small angle neutron scattering, neutron spin echo, backscattering, time-of-flight technique, reflectivity and grazing-incident small angle neutron scattering. In the present review, we focus on functionalized polymers such as polyrotaxane, Nafion, polymer/nano composite system, and casein protein thin films, which are of great interest from both scientific and industrial viewpoints. We also state some future experiments at J-PARC. (author)

  20. SMALL-ANGLE NEUTRON SCATTERING CHARACTERIZATION OF THE STRUCTURE OF NANOPOROUS CARBONS FOR ENERGY-RELATED APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    He, Lilin [ORNL; Mavila Chathoth, Suresh [ORNL; Melnichenko, Yuri B [ORNL; Presser, Volker [Drexel University; Mcdonough, John [Drexel University; Gogotsi, Yury G. [Drexel University

    2011-01-01

    We used small-angle neutron scattering (SANS) and neutron contrast variation to study the structure of four nanoporouscarbons prepared by thermo-chemical etching of titanium carbide TiC in chlorine at 300, 400, 600, and 800 C with pore diameters ranging between -4 and -11 {angstrom}. SANS patterns were obtained from dry samples and samples saturated with deuterium oxide (D{sub 2}O) in order to delineate origin of the power law scattering in the low Q domain as well as to evaluate pore accessibility for D{sub 2}O molecules. SANS cross section of all samples was fitted to Debye-Anderson-Brumberger (DAB), DAB-Kirste-Porod models as well as to the Guinier and modified Guinier formulae for cylindrical objects, which allowed for evaluating the radii of gyration as well as the radii and lengths of the pores under cylindrical shape approximation. SANS data from D{sub 2}O-saturated samples indicate that strong upturn in the low Q limit usually observed in the scattering patterns from microporous carbon powders is due to the scattering from outer surface of the powder particles. Micropores are only partially filled with D{sub 2}O molecules due to geometrical constraints and or partial hydrophobicity of the carbon matrix. Structural parameters of the dry carbons obtained using SANS are compared with the results of the gas sorption measurements and the values agree for carbide-derived carbons (CDCs) obtained at high chlorination temperatures (>600 C). For lower chlorination temperatures, pore radii obtained from gas sorption overestimate the actual pore size as calculated from SANS for two reasons: inaccessible small pores are present and the model-dependent fitting based on density functional theory models assumes non-spherical pores, whereas SANS clearly indicates that the pore shape in microporous CDC obtained at low chlorination temperatures is nearly spherical.