Structure of pure L64 **in** D 2 O: Before characterizing the morphologies **in** presence of TBP,
we have performed a structural **study** by Small Angle **Neutron** **Scattering** (SANS) of the pure aqueous copolymer solutions at 308 K. As one can see from the phase diagram **in** Fig. 1b, a transparent phase of pure copolymer L64 is formed **in** the absence of TBP. We have characterized the morphology of the aggregates by SANS **in** D 2 O for obvious contrast reasons, the average **scattering** length density of L64 being 0.43x10 10 cm -2 . The results are shown **in** Figure 2 for three different concentrations (0.2%wt, 5%wt, 10%wt), after subtraction of the unimer **scattering** for the two higher concentrations as explained below. At the highest dilution, which is below the cmc (≈0.35%wt, cf. supporting information SI) the **scattering** pattern I(q) is due to the individual unimers **in** solution. The low-q limit I o (0.023 cm -1 ) corresponds to a dry volume of 3300 Å 3 , and the radius of gyration, deduced from the Guinier fit - eq.(1) applied to unimers - **in** Fig.2, is 18.5 Å. Both values clearly correspond to individual molecules, which have a dry volume of 4640 Å 3 estimated from the molecular mass. The discrepancy may be due to the low scattered intensity **in** this case of **scattering** by individual molecules, but the order of magnitude remains correct.

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Abstract
**In** the international **neutron** libraries, the behavior with the energy of the **neutron** cross sec- tions of hydrogen **in** **light** **water** depends on the thermal **scattering** laws tabulated **in** terms of S (α, β). For the Joint Evaluated Fission and Fusion library (JEFF), Mattes and Keinert have established thermal **scattering** laws by using the LEAPR module of the NJOY code. However, uncertainties on the corresponding S (α, β) were never reported. Such missing information was recently calculated with the nuclear data code CONRAD by determining the covariances between the model parameters involved **in** LEAPR. The obtained uncertainties were propagated to reac- tivity coe fficients calculated for critical assemblies operating **in** ”cold” conditions (temperature below 80 ◦ C) and for PWR **in** ”hot” operating conditions (300 ◦ C). For the integral benchmarks

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coalescence), if particle size is altered. Among the proper- ties enhancing emulsion stability, let us list: a low dispersed-phase volume fraction, a low density difference between phases, a low (but not too low) interfacial tension, a high viscosity of the continuous phase, a high mechanical resistance and elasticity of the interface, a high f potential, a high solubility of the emulsifier **in** the continuous phase (Bancroft’s rule), a narrow droplet size distribution. Increasing temperature often accelerates emulsion breaking. Except **in** special cases where spontaneous emulsification can occur, [9,10] and without neglecting the advantages of a lot of emulsification techniques, [11,12] mechanical agitation under turbulent flow regime remains the most common emulsification method, especially **in** large-scale operation. [12–16] Emulsification under mechan- ical agitation is described either by a kinetic model adapted to take into account the parameters of formulations or by a hydrodynamic approach better suited to describe the emul- sification process. [17] The formulation, properties and stab- ility of emulsions have been described throughout the literature. [18–21] As for the theoretical analysis and com- parison of emulsification processes, they have given rise to a few recent papers. [11,12,17,20,22] The present **study** aims at a better understanding of the effect of emulsifier and process variables on oil-**in**-**water** (O=W) emulsion proper- ties and behavior: droplet size distribution (DSD), viscosity, shelf stability and breakup modes, by evaluating and optimizing emulsifier properties and process para- meters **in** order to prepare the most stable (optimal) mixture. Emulsion stability will be monitored with two recently developed techniques (multiple **light** **scattering** and acoustic attenuation spectroscopy), still rarely used and providing immediately applicable practical guidelines for the control of emulsion properties.

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Key Words: **light** **water**, thermal **scattering** law, reactivity temperature coefficient, Mis- tral.
1. INTRODUCTION
The Mistral experimental program [1], carried out **in** EOLE reactor at CEA Cadarache (France), was developed to test the feasibility of charging 100% MOX fuel **in** nuclear power plants. Among many neutronic parameters, it was measured the reactivity temperature coefficient (RTC) for the configurations Mistral-1 (UOX lattice), Mistral-2 and Mistral-3 (MOX lattices) between 10°C and 80°C.The interpretation of this parameter was performed with the Monte Carlo code TRIPOLI4 [2]. The nuclear data from JEFF-3.1.1 library [3] was used **in** the calculations.

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cross sections from the JEFF-3.1 library. Group constants are calculated by first homogenizing the geometry using an intermediate multi-group structure with g-groups, and then collapsed into few- group structure with G-groups using infinite-medium and B1 leakage-corrected **neutron** spectra.
A simplified 2-D core design representative of an experimental **light** **water** reactor is used for the generation of the cross sections needed **in** the **study**. The core has 3x3 fuel assemblies, each assem- bly containing 17x17 pins fueled with UOX and surrounded by **water**. The vibrating fuel assembly is chosen to have a slightly lower enrichment (2.5% UOX) compared to the rest of the fuel assem- blies (3.7% UOX). This is done to ensure the changes **in** cross sections between the neighboring fuel assemblies are higher than their statistical fluctuations, when generating the cross sections with a Monte-Carlo code. **In** this work, diffusion coefficient, absorption cross section, removal cross section derived from the **scattering** cross section and ν-weighted fission cross sections **in** fast (G=1) and thermal (G=2) energy group with a cut-off at 0.625 eV are the input macroscopic data. The removal cross section is defined as the isotropic down-**scattering** cross section minus the isotropic up-**scattering** cross section weighted with the ratio between the thermal and the fast **neutron** fluxes. The parameter ν is the average number of neutrons emitted per fission. For the pin calculations, the cross section for the fuel and moderator are calculated separately, at the pin level, unlike the homogenization of the entire fuel assembly for calculation of nodal cross sections.

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3
and diluted monomers were prevailing for high and low values of x respectively (cf. Fig. 12 **in** ref. [10]).
**In** this article, we extend the **study** of the segregation phenomenon towards a lower q- region. Small angle **neutron** **scattering** (SANS) is a complementary method to address the inhomogeneity of the mixtures **in** terms of concentration fluctuations, which are signatures of single-component-rich domains triggered by selective molecular interactions. Different hydrogenated/deuterated isotopic compositions are used to vary the **scattering** length density of the components of the binary liquids, and optimize the contrast between domains of different compositions. The characteristic correlation length of the inhomogeneities has been determined using the Ornstein-Zernike model [31]. An alternative approach, based on the Guinier approximation was applied, indicating that the observed inhomogeneity could be expressed **in** terms of weakly interacting spherical particles with diameter comparable to the H-bonded multimers [32]. The formalism of Bhatia and Thornton has been applied to decouple the different correlation functions related to density and concentration from the total **neutron** structure factor at zero-q [33]. The fluctuations of the local composition have been quantified by the evaluation of the Kirwood-Buff integrals (KBI), which can be determined from the experimental forward **scattering** intensities [34].

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dynamics and relaxation processes over a wide range of momentum (Q) and energy (ħω) transfers at nano- to picosecond timescales relevant to cellular biology 7–9 . **In** our experiment these correspond to a spectral broadening
of the elastic line exceeding the energy resolution by a few tenths of meV. Therefore, the dynamics probed by QENS are readily distinguished from vibrational excitations or events such as enzyme catalysis that occur on significantly faster (fs) or slower (ms) timescales, respectively. QENS signals arise from incoherent **scattering** processes. Because of the large differences **in** H/D **neutron** **scattering** cross sections, isotopic contrast experiments can be designed to focus on the dynamics occurring within specific regions of the biological cell, including the intracellular medium (Im) or across membrane structures. QENS has already been developed to **study** high pressure effects on dynamic

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electric field lines without breaking of the local tetrahedral symmetry. The experiment is carried out by **neutron** **scattering** on a D 2 O bridge.
Introduction
**In** 1893 Sir William Armstrong placed a cotton thread between two wine glasses filled with chemically pure **water**. After applying a high voltage, a watery connection formed between the two glasses, and after some time, the cotton thread was pulled into one of the glasses, leaving, for a few seconds, a rope of **water** suspended between the lips of the two glasses [1]. As gimmick from early days of electricity this experiment was handed down through history until the present authors learned about it from W. Uhlig, ETH Zürich [2]. Although easy to reproduce, this watery connection between the two beakers, which is further referred to as 'floating **water** bridge' or ‘floating heavy **water** bridge’ **in** the case of D 2 O, respectively, holds a number of interesting static and dynamic phenomena [3-8].

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We will finally comment on the 1/Q underlying trend of
diffracted intensity. This component of **scattering**, seen as a straight line of slope –1 **in** a log–log plot (inset **in** Fig. 2), is the signature of **scattering** from a powder sample that con- tains phase-correlated regions within which the **scattering**- length density fluctuates **in** two orthogonal directions but re- mains constant **in** the third direction. Given that our sample is prepared from a template material that forms long parallel cylinders it is not surprising to have this component of scat- tering. Re-plotting all our data on the log–log plot shows that the 1/Q component exists at every pressure, increases and passes through a maximum as the pores **in** the MCM- 41 are filled and reduces back approximately to the initial magnitude at the end of filling, i.e., it persists even when the pores are filled. Therefore, we conclude the 1/Q compo- nent does not originate from the pores themselves — if so, it would have been wiped out or greatly reduced when the pores are filled with a contrast-matched material. The 1/Q component is a measure of lateral (i.e., perpendicular to the cylindrical axis of the pores) correlations that are beyond the mesopore structure. They may be features caused by imper- fect hexagonal packing or by inaccessible pores that are ran- domly distributed throughout the lattice. We cannot speculate much further except to recognize that these are the correlations not affected by the presence of pentane for 8 days, nor by traversing the adsorption–desorption cycle once.

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samples have internal radii equal to 7.5 and 9.8 ˚A, respectively. By working under well-deﬁned relative humidity (RH) values, **water** dynamics **in** IMO-OH was revealed by quasi-elastic spectra as a function of the ﬁlling of the interior of the tubes. When one **water** monolayer is present on the inner surface of the tube, **water** molecules can jump between neighboring Si –OH sites on the circumference by 2.7 ˚A. A self-di ﬀusion is then measured with a value (D ¼ 1.4 10 5 cm 2 s 1 ) around half of that **in** bulk **water**. When **water** molecules start ﬁlling also the interior of the tubes, a strong conﬁnement eﬀect is observed, with a con ﬁnement diameter (6 ˚A) of the same order of magnitude as the radius of the nanotube (7.5 ˚A). When IMO-OH is ﬁlled with **water**, the H-bond network is very rigid, and **water** molecules are immobile on the timescale of the experiment. For IMO-OH and IMO-CH 3 , motions of the hydroxyl groups are also

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(GPDs) particularly sensitive to E q , the least constrained GPD. A model dependent constraint on
the contribution of the up and down quarks to the nucleon spin is deduced. PACS numbers: 13.60.Fz, 13.85.Hd, 14.20.Dh, 14.65.-q
Understanding the structure of the nucleon **in** terms of quarks and gluons is a central project of modern hadronic physics. **In** the non-perturbative regime relevant to nu- clear scales, Quantum Chromodynamics (QCD), the the- ory describing the elementary dynamics of the nucleon, is not yet solvable and remains rather mysterious. The electromagnetic probe provides an outstanding tool to **study** the nucleon structure. **In** this letter, we present the first **study** of the (~e, e ′

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CAC: critical aggregation concentration NZS: Zetasizer Nano ZS
Introduction
During the past few years, the copolymer poly(vinylidene difluoride-trifluoroethylene) P(VDF-TrFE) has attracted a growing interest, mainly because of its ferroelectric, pyroelectric and dielectric properties. Indeed, its high dielectric constant is useful **in** a large range of capacitor applications [1]. To improve the dielectric constant and thus the capacitance, or its ferroelectric properties, extensive research on P(VDF-TrFE) was carried out as it is but also as a matrix for nanocomposites [2]. These nanocomposites were prepared by incorporating various nanoparticles (NPs) **in** P(VDF-TrFE) **in** order to obtain reinforced materials with better mechanical properties or to add new properties to the matrix such as piezoelectric or nonlinear optical properties [3–6] .**In** these materials, the ultrasonication step is crucial. A good dispersion of nanoparticles is necessary to strengthen mechanical properties of the material, such as the elastic constant. This was observed for various polymers and even **in** oligomers[3–6].The goal of the dispersion, performed by ultrasonication, is generally to break the agglomerates of NPs, and,**in** the process, to decrease their hydrodynamic volume, which is the apparent volume occupied by a spherical (organic or inor

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Structural Parameters from the T-S Model. The T-S
**scattering** function reveals important local structures about the PEMs. The best-fitting correlation length, ξ, decreases, while the domain periodicity, d, increases with increased hydrophilic side-chain fraction. Studies on the shift of the ionomer peak of Nafions follow the same trend as that of the current PEM samples, i.e., moving toward lower q with increased hydra- tion. 1–8 The previous explanation was that this was caused either by a swelling of ionomer clusters (**in** the core-shell model) 2,3 or by a swelling of ionomer spacing. 4,5 The T-S model agrees more with the latter, yet assuming a random distribution of the ionomers clusters (presumably **in** **water** channels) similar to microemulsion **in** contrast to the constrained locally ordered ionomers. 4 Teubner and Strey confirmed that the value of ξ/d increased with surfactant concentration **in** the case of micro- emulsion. 18 **In** this comb-shaped PEM, the side-chain sulfonic acid groups seemingly serve a similar function of a surfactant bridging the polymer backbone (oil phase) and waterssequestering the interface of **water** channel and polymer matrix. However, a lower value of ξ/d of PEM-32 is obtained from the best-fitting result (**in** Table 2). This can be rationalized if the contrast of the “ionomer peak” arises from the side-chain-rich regions and embedded **water**-rich ionomers (as shown **in** Figure 6d). Then, ξ/d is expected to decrease with increased volume fraction of hydrophilic side chains.

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Keywords: **Scattering**; Roughness; Fractal; Self-ane; Aluminum
Since an early paper by Berry **in** 1979 [1], the **study** of wave **scattering** from self-ane (fractal) surfaces has become very active, see Refs. [2±10] for recent references. Most of these papers consist **in** numerical simulations; apart from the early works of Jakeman [11] and Jordan et al. [12] very few theoretical results have been published; the same statement stands for experimental results while lots of real surfaces [13±15] have been shown to obey scale invariance. Here we try and test ex- perimentally recent theoretical expressions ob- tained for the **scattering** of a scalar wave from a perfectly conducting self-ane surface [16]. We report **scattering** measurements of an s-polarized electromagnetic wave (632.8 nm) from a rough aluminum alloy plate (Al 5182). The latter was obtained by industrial cold rolling. As presented **in**

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functions, such as the photo cycle ( Luecke et al., 1999b ) and signal transmission.
8. Concluding remarks
Diffraction techniques, especially with regards to X-rays, have traditionally been used to determine the structure of 3D crys- tals. Over the past decades, X-ray diffraction has been used to elucidate the structure of a wide range of materials to atomic res- olution – starting with common table salt **in** 1914. However, a few decades ago nobody could have envisioned that diffraction tech- niques would develop to an extent that they would successfully characterize the physical properties of disordered materials, such as biomimetic membranes. **In** this review we have presented some of the latest research regarding the application of X-ray and **neutron** **scattering** methods to elucidate the material properties previously thought to be the domain of other techniques (e.g. NMR and Raman spectroscopies, optical and electron micrscopies, etc.). Over the next decade, as some of the techniques discussed here and others (e.g. MD simulations, various optical microscopies, to name but a few) reach maturity, we will for the first time have unique access to the much touted structure–function relationship that is universally sought out **in** biology.

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These first results can be considered as very promising: let us recall that we assumed the surface to be purely one-dimensional and perfectly conducting and that we used a basic Kirchhoff approximation, neglecting all shadowing or multiple **scattering** effects... Refining the modeling of shadowing or multiple **scattering** **in** the specific case of self-affine surfaces could allow to design a valuable tool to measure the geometrical parameters describing self-affine surfaces. This experimental **study** also makes clear that self-affine correlations can be a relevant formalism to describe the optical properties of real surfaces. Beyong classical optical phenomena this could be also of great interest **in** the context of the recent studies [23, 24] modeling thermal emission properties of rough surfaces.

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been realized for N = 500 atoms with b 0 = 5, standard
deviation σ R = 17.32/k and for two different detuning,
δ = 4.5 and δ = 0, corresponding to b(δ) = 0.061 and b(δ) = 5, respectively. For the case of small optical thick- ness (b(δ) = 0.061), the field decreases as the **scattering** order n increases, and the series (11) converges. For the case of larger optical thickness (b(δ) = 5), the presence of eigenvalues of modulus larger than unity makes the multiple **scattering** series diverge. Hence, **in** presence of above-unity eigenvalues of G, the multiple **scattering** de- scription loses its validity: for sufficiently dense media, due to the long-range interaction of the Green’s func- tion, the build-up of the scattered radiation field cannot be seen as the sum of interactions involving an increas- ing number of atoms, and the local iteration of the scat- tering event described by Eq.(10) is no longer possible. Instead, the total scattered field is a result of a global **in**- teraction with the entire sample. Let us remark that the criterion of all eigenvalues having modulus below unity for the convergence of the series is **in** agreement with the results of Ref.[28]. A detailed **study** of the typical spec- trum of the linear operator **in** (10) has been proposed **in** [29], yet it is important to mention that the spectrum exhibits strong fluctuations from one realization to an- other. Since the multiple **scattering** process corresponds to a geometric series, the radiated power grows or de- creases as a power-law of the largest eigenvalue of the linear operator **in** Eq.(10) for large n.

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