Complementary Measurement Research Articles

Constraining P and T violating forces with chiral molecules

New sources of parity and time-reversal violation are predicted by well motivated extensions of the Standard Model and can be effectively probed by precision spectroscopy of atoms and molecules. Chiral molecules have distinguished enantiomers which are related by parity transformation. Thus they are promising candidates to search for parity violation at molecular scales, which has yet to be observed. In this work, we show that precision spectroscopy of the hyperfine structure of chiral molecules is sensitive to new physics sources of parity and time-reversal violation. In particular, such a study can be sensitive to regions unexplored by terrestrial experiments of a new chiral spin-1 particle that couples to nucleons. We explore the potential to hunt for time-reversal violation in chiral molecules and show that it can be a complementary measurement to other probes. We assess the feasibility of such hyperfine metrology and project the sensitivity in CHDBrI+. Published by the American Physical Society 2024

Soluble mineral flotation paradox: Improved recovery with no sign of collector adsorption on minerals signifies colloidal attraction between bubble-bound collector colloids and mineral particles

Froth flotation uses air bubbles to separate mineral particles based on the difference in mineral surface hydrophobicity. Collectors are needed to selectively hydrophobize the surface of targeted minerals to augment the difference in surface hydrophobicity between wanted minerals and unwanted ones. Here, we showed that this classical (well-established) principle fails to describe the flotation of water-soluble minerals. Our systematic micro-flotation tests using soluble minerals (NaCl and KCl crystals) in brines and three popular collectors (dodecylamine hydrochloride, sodium dodecylsulfate, and sodium laurate) showed a substantial flotation recovery of the salt minerals without detected collector adsorption at the mineral surfaces by X-ray photoelectron spectroscopy (XPS). Complementary particle size distribution measurement indicated the occurrence of sub-micron collector colloids in saturated brines. Moreover, the flotation recovery agreed well with the measured contact angle, suggesting the attraction between bubble-bound collector colloids and salt crystal surfaces. These paradoxical results signify a new principle underlying the flotation of soluble minerals, i.e., the selective colloidal attraction between bubble-bound collector colloids and salt particles enables the flotation separation of soluble minerals.

Accurate Measurement of the Lensing Magnification by BOSS CMASS Galaxies and Its Implications for Cosmology and Dark Matter

Magnification serves as an independent and complementary gravitational lensing measurement to shear. We develop a novel method to achieve an accurate and robust magnification measurement around BOSS CMASS galaxies across physical scales of 0.016h −1 Mpc < r p < 10h −1 Mpc. We first measure the excess total flux density δ M of the source galaxies in the deep DECaLS photometric catalog that are lensed by CMASS galaxies. We convert δ M to magnification μ by establishing the δ μ–δ M relation using a deeper photometric sample. By comparing magnification measurements in three optical bands (grz), we constrain the dust attenuation curve and its radial distribution, discovering a steep attenuation curve in the circumgalactic medium of CMASS galaxies. We further compare dust-corrected magnification measurements to model predictions from high-resolution dark matter-only (DMO) simulations in Wilkinson Microwave Anisotropy Probe (WMAP) and Planck cosmologies, as well as the hydrodynamic simulation TNG300-1, using precise galaxy–halo connections from the Photometric objects Around Cosmic webs method and the accurate ray-tracing algorithm P3MLens. For r p > 70h −1 kpc, our magnification measurements are in good agreement with both WMAP and Planck cosmologies, resulting in an estimation of the matter fluctuation amplitude of S 8 = 0.816 ± 0.024. However, at r p < 70h −1 kpc, we observe an excess magnification signal, which is higher than the DMO model in Planck cosmology at 2.8σ and would be exacerbated if significant baryon feedback is included. Implications of the potential small scale discrepancy for the nature of dark matter and for the processes governing galaxy formation are discussed.

In Situ Studies on the Influence of Surface Symmetry on the Growth of MoSe2 Monolayer on Sapphire Using Reflectance Anisotropy Spectroscopy and Differential Reflectance Spectroscopy

The surface symmetry of the substrate plays an important role in the epitaxial high-quality growth of 2D materials; however, in-depth and in situ studies on these materials during growth are still limited due to the lack of effective in situ monitoring approaches. In this work, taking the growth of MoSe2 as an example, the distinct growth processes on Al2O3 (112¯0) and Al2O3 (0001) are revealed by parallel monitoring using in situ reflectance anisotropy spectroscopy (RAS) and differential reflectance spectroscopy (DRS), respectively, highlighting the dominant role of the surface symmetry. In our previous study, we found that the RAS signal of MoSe2 grown on Al2O3 (112¯0) initially increased and decreased ultimately to the magnitude of bare Al2O3 (112¯0) when the first layer of MoSe2 was fully merged, which is herein verified by the complementary DRS measurement that is directly related to the film coverage. Consequently, the changing rate of reflectance anisotropy (RA) intensity at 2.5 eV is well matched with the dynamic changes in differential reflectance (DR) intensity. Moreover, the surface-dominated uniform orientation of MoSe2 islands at various stages determined by RAS was further investigated by low-energy electron diffraction (LEED) and atomic force microscopy (AFM). By contrast, the RAS signal of MoSe2 grown on Al2O3 (0001) remains at zero during the whole growth, implying that the discontinuous MoSe2 islands have no preferential orientations. This work demonstrates that the combination of in situ RAS and DRS can provide valuable insights into the growth of unidirectional aligned islands and help optimize the fabrication process for single-crystal transition metal dichalcogenide (TMDC) monolayers.

Relationship between IDDSI Flow Test and Consistometric Measures for Consistency Classification - An Examination of Thickened Liquids Prepared Using Starch-Based and Xanthan Gum-Based Thickening Agents.

Consistency of liquid food plays an important role in managing patients with dysphagia, which can be objectively evaluated by using IDDSI Flow Test and consistometry. The present study established the relationship between IDDSI Flow Test and consistometric measures, and examined the measurement limitations of each test associated with thickened liquids prepared using starch-based and xanthan gum-based thickening agents. Thirteen thickened liquid samples of consistency ranging from IDDSI Level 1 (mildly thick) to Level 3 (moderately thick) were prepared using starch-based and xanthan gum-based thickeners. IDDSI Flow Test and consistometric measures were obtained and analyzed using correlation and regression. A strong correlation was observed between both tests. Regression analyses revealed a linear and a quadratic relationship between IDDSI Flow Test and consistometric measurements, respectively. Starch-based and xanthan gum-based thickeners exhibited different relationships between IDDSI Flow Test and consistometric measurements. Findings allow easy conversion and adaptation of consistometric measures to the IDDSI framework, which renders the use of consistometry in the clinical settings as a complementary quantitative measurement of liquid consistency to IDDSI Flow Test.

A multi-scale information integration framework for infrared and visible image fusion

Infrared and visible image fusion aims at generating a fused image containing the intensity and detail information of source images, and the key issue is effectively measuring and integrating the complementary information of multi-modality images from the same scene. Existing methods mostly adopt a simple weight in the loss function to decide the information retention of each modality rather than adaptively measuring complementary information for different image pairs. In this study, we propose a multi-scale dual attention (MDA) framework for infrared and visible image fusion, which is designed to measure and integrate multi-scale complementary information in both structure and loss function at the image and patch level. In our method, the residual downsample block decomposes source images into three scales first. Then, dual attention fusion block integrates complementary information and generates a spatial and channel attention map at the same and adjacent scale for feature fusion. Finally, the output image is reconstructed by the residual reconstruction block. Loss function consists of image-level, feature-level and patch-level three parts, of which the calculation of the image-level and patch-level two parts are based on the weights generated by the complementary information measurement. Indeed, to constrain the pixel intensity distribution between the output and infrared image, a style loss is added. Our fusion results perform robust and informative across different scenarios. Qualitative and quantitative results on three datasets illustrate that our method is able to preserve both thermal radiation and detailed information from two modalities and achieve comparable results compared with the other state-of-the-art methods. Ablation experiments show the effectiveness of our information integration architecture and adaptively measure complementary information retention in the loss function. Our code is available at https://github.com/SSyangguang/MDA.

3D printed stretchable coaxial fiber grid for dual-mode multifunctional tactile sensor array

Tactile sensors play a critical role in the Internet of Things (IoT) and wearable devices. However, although current tactile sensors can precisely measure pressure, the simple fabrication of stretchable high-performance tactile sensors with a broad measuring range and multifunctions is still challenging. Herein, an ink-direct writing 3D printing method is developed to fabricate novel stretchable dual-mode tactile sensors with coaxial fiber structure. The 3D printed coaxial fibers have an outer skin composed of silicone rubber and polytetrafluoroethylene micropowders thixotropic agent and an inner core of an ionic conductive solution composed of polyvinyl alcohol and sodium chloride. The coaxial fibers exhibit excellent electrical conductivity (0.54 S cm−1) and outstanding stretchability, as high as 390 %. The intersection of the two fibers constitutes a dual-mode tactile sensor which can operate in triboelectric or capacitive modes with complementary measurement ranges from 0.0003 to 0.4517 N. Besides, by combining the signals from the two modes, the sensor can identify the material that comes into contact with the sensor. A 3D printed network of tactile sensor arrays made of warp-weft interwoven coaxial fibers is able to accurately detect the locations of multi-point contact with the array. This dual-mode multifunctional tactile sensor can be widely used in various applications such as the IoT and wearable devices.

Relationship Between Diameter and Pelvic Vein Reflux

Introduction: Diameter has been a complementary measurement in the evaluation of venous valvular insufficiency of superficial veins of the lower extremity. Small veins with reflux or large veins without reflux may indicate alternative treatments. Awareness of pelvic vein reflux is increasing. The pelvic vein diameter-reflux relationship was investigated. Methods: Findings of lower extremity ultrasound (US) and/or clinical conditions—pelvic pain, dyspareunia and dysmenorrhoea—were indications for pelvic/abdominal venous US. Complete US examination included renal, internal iliac and gonadal/ovarian veins. Diameters of the largest right or left pelvic veins were compared with presence of reflux. Intravaginal US was completed in 104 women, age 46 ± 11 (standard deviation) (range 25-76) years old. Pelvic symptoms were reported by 30 (29%) patients. The other patients had pelvic-related recurrent varicose veins or suspected pelvic source of lower extremity venous reflux. Positive and negative predictive values (PPV, NPV) and other statistics at the 90-95% level were calculated relating diameter to pelvic vein reflux. Results: Pelvic vein reflux was detected in 54 (52%) women. Pelvic vein diameters were larger in refluxing, 8.4 ± 1.9 (5.1-14.0) mm, than in nonrefluxing veins, 5.2 ± 1.0 (3.4-8.3) mm ( P &lt; .001 by t test). Diameters ≥6.3 mm had 91% (49/54) sensitivity and 92% (49/53) PPV. Diameters ≤6.3 mm had 94% specificity (47/50) and 89% (47/53) NPV. All veins with diameter ≥8.4 mm ( n = 21) had reflux. All veins with diameter ≤5.0 mm ( n = 27) did not have reflux. Conclusions: Probabilities of pelvic vein reflux were estimated based on diameters. Diameter-reflux agreement solidifies diagnosis. An explanation for contradiction between small diameter and reflux or large diameter and no reflux is recommended.

Assessment of the visibility of unprotected road users in pedestrian crossing

The article presents selected results of research on improving pedestrian traffic safety. Based on annually-updated accident statistics made available by the police, as well as the new pedestrian traffic regulations in force, detailed work was undertaken to assess the level of visibility of pedestrians by drivers in pedestrian crossing areas. The research was carried out by analyzing several characteristic cases of pedestrian crossings occurring in Poland, in which there was only dedicated lighting for crossings, only street lighting, and a variant of coexistence of both of the above lighting solutions. Illuminance measurements were made in the horizontal and vertical planes of pedestrian crossings, and the results were confronted with the relevant guidelines. The next step involved a complementary measurement of the luminance distribution of the vertical plane containing the pedestrian and a portion of the sub- and super-horizontal background. Visibility pedestrians was considered in positive and negative contrast variants, and was then related to the obtained results of the illumination distribution. The analysis of the results of the study indicated the possibility of limited visibility of pedestrians at the crossings despite the satisfactory results obtained from measurements of the illuminance distribution within the crossings.

Characterization of 235U, 238U and 239Pu fission ionization chamber foils by [formula omitted] and [formula omitted]-ray spectrometry

The masses of thin, electroplated deposits of 235U, 238U and 239Pu on titanium backings have been determined to better than 1.3% precision by employing three complementary measurement techniques: α spectrometry, 2π gas counting, and γ-ray spectrometry. A dedicated α spectrometer was designed and calibrated to allow for repeatable, high-precision measurements of the absolute α activity of a sample. The isotopic composition of the sample was determined by fitting the peaks in the α spectrum, a technique which was demonstrated to be generally consistent with mass spectrometry. Independently, the total activity of the deposits were measured in a 2π gas flow proportional counter. A detailed study of the effects of α particle straggling in the actinide deposit and α particle recoil off the sample backing material was performed. The masses of these actinide deposits were also measured via γ-ray spectrometry. We found that all three systematically independent techniques produced consistent results, and could be combined into a weighted average with further reduced uncertainty. The mass ratios of these actinide deposits were determined to better than 1% precision via α spectrometry, enabling high-precision fission cross section ratio measurements.

Industrial application of a low-cost structural health monitoring system in large-scale airframe tests

A small, novel, integrated SHM system has been deployed during full-scale testing of a wing fatigue test for several weeks and a fuselage pressurisation test for several months. Complementary NDE measurement techniques were combined, with inputs from visible and infrared optical sensors, as well as resistance strain gauges. Sensor units were deployed at regions of interest and integrated board computers permitted near real-time data processing. The outputs were full-field measurement datasets from digital image correlation and thermoelastic stress analysis systems. Changes in these datasets in the regions of interest were successfully quantified using orthogonal decomposition and were indicative of changes in the condition of the structure. The results from these case studies demonstrate that this system can be successfully deployed in spatially restricted areas within airframe structures to monitor crack growth. The low cost and small footprint of the system presents the opportunity for installation of arrays of similar sensors for both test and in-service data collection. Near real-time data processing would allow timely reporting to service engineers, informing maintenance or operational decisions.

Bovine Serum Albumin as a Platform for Designing Biologically Active Nanocarriers-Experimental and Computational Studies.

Due to the specificity of their structure, protein systems are adapted to carry various ligands. The structure of many proteins potentially allows for two types of immobilization of a therapeutic agent, either on the outer surface of the protein or within the protein structure. The existence of two active sites in BSA's structure, the so-called Sudlow I and II, was confirmed. The conducted research involved determining the effectiveness of BSA as a potential carrier of 5-fluorouracil (5FU). 5-fluorouracil is a broad-spectrum anticancer drug targeting solid tumors. The research was carried out to estimate the physicochemical properties of the system using complementary measurement techniques. The optimization of the complex formation conditions made it possible to obtain significant correlations between the form of the drug and the effective localization of the active substance in the structure of the protein molecule. The presence of two amino groups in the 5FU structure contributes to the deprotonation of the molecule at high pH values (pH > 8) and the transition to the anionic form (AN1 and AN3). To investigate the binding affinity of the tautomeric form with BSA, UV-vis absorption, fluorescence quenching, zeta potential, QCM-D, and CD spectroscopic studies were performed. The experimental research was supported by molecular dynamics (MD) simulations and molecular docking. The simulations confirm the potential location of 5FU tautomers inside the BSA structure and on its surface.

Residual Stresses in Alloy IN718 Produced Through Modulated Laser Powder Bed Fusion

BackgroundLaser powder bed fusion (L-PBF) additive manufacturing (AM) is used for building metallic parts layer-by-layer and often generates non-uniform thermal gradients between layers during fabrication, resulting in the development of residual stresses when parts are cooled down.ObjectiveThe impact of modulated laser used during the L-PBF process on residual stresses in Inconel 718 (IN718) material was investigated. The impact of build directions on residual stress is also determined.MethodsThe contour method is employed to measure the full-field residual stress component on the cross-section of samples. A complementary residual stress measurement method, incremental hole drilling, was employed for obtaining in-plane residual stress components.ResultsThe results show that the residual stress distribution is sensitive to the build direction, with a higher magnitude of residual stress in the direction of build than that in the transverse direction. Multiple measurements with the same manufacturing parameters show good repeatability.ConclusionResidual stresses in the as-built parts are significant and hence a further consideration regarding relieving residual stresses is required when post-thermal treatments are developed.

CLYC as a neutron detector in low background conditions

We report on the thermal neutron flux measurements carried out at the Laboratorio Subterráneo de Canfranc (LSC) with two commercial 2″×2″\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$2^{\\prime \\prime } \ imes 2^{\\prime \\prime }$$\\end{document} CLYC detectors. The measurements were performed as part of an experimental campaign at LSC with 3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{3}$$\\end{document}He detectors, for establishing the sensitivity limits and use of CLYCs in low background conditions. 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The simulations and unfolding also revealed that the γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray background registered in the detectors is dominated by the intrinsic activity of the components of the detector such as the aluminum housing and photo-multiplier and that the activity within the crystal is low in comparison. The data from the neutron flux measurements with the two detectors were analyzed with different methodologies: one based on an innovative α\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\alpha $$\\end{document}/neutron pulse shape discrimination method and one based on the subtraction of the intrinsic α\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\alpha $$\\end{document} background that masks the neutron signals in the region of interest. The neutron sensitivity of the CLYCs was calculated by Monte Carlo simulations with MCNP6 and GEANT4. 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Ground Truth Validation of Sentinel-2 Data Using Mobile Wireless Ad Hoc Sensor Networks (MWSN) in Vegetation Stands

Satellite-based remote sensing (RS) data are increasingly used to map and monitor local, regional, and global environmental phenomena and processes. Although the availability of RS data has improved significantly, especially in recent years, operational applications to derive value-added information products are still limited by close-range validation and verification deficits. This is mainly due to the gap between standardized and sufficiently available close-range and RS data in type, quality, and quantity. However, to ensure the best possible linkage of close-range and RS data, it makes sense to simultaneously record close-range data in addition to the availability of environmental models. This critical gap is filled by the presented mobile wireless ad hoc sensor network (MWSN) concept, which records sufficient close-range data automatically and in a standardized way, even at local and regional levels. This paper presents a field study conducted as part of the Durable Environmental Multidisciplinary Monitoring Information Network (DEMMIN), focusing on the information gained with respect to estimating the vegetation state with the help of multispectral data by simultaneous observation of an MWSN during a Sentinel-2A (S2A) overflight. Based on a cross-calibration of the two systems, a comparable spectral characteristic of the data sets could be achieved. Building upon this, an analysis of the data regarding the influence of solar altitude, test side topography and land cover, and sub-pixel heterogeneity was accomplished. In particular, variations due to spatial heterogeneity and dynamics in the diurnal cycle show to what extent such complementary measurement systems can improve the data from RS products concerning the vegetation type and atmospheric conditions.

Dynamics of physical flows measured by positron emission techniques

Short lived positron emitting species are used to produce flow-following tracer particles to study flow dynamics in a technique known as positron emission particle tracking (PEPT). The photon pairs produced by positron annihilation are detected in time coincidence by arrays of high-speed position sensitive detectors. Reconstruction of consecutive annihilations are used to determine the near-instantaneous position of the tracer particle. Hence, the resulting bulk flow dynamics are derived, including residence times, velocities, accelerations, and related kinematic properties. The Department of Physics at the University of Cape Town uses PEPT to study dynamic physical processes, turbulent, and multiphase flows. Studies aim to address global challenge topics including problems in water scarce environments, reducing industrial wastes, and enhancing developments towards sustainable economies through improved process efficiencies and design led approaches. The PEPT Cape Town enterprise is discussed, including the development of flow metrology systems and complementary nuclear measurement techniques. Research encompasses four key themes: radioisotope tracer production, instrumentation & detector development, data acquisition & processing, and flow metrology.

Distributed observer for linear systems with bounded unknown inputs

In this paper, a fully distributed unknown input observer is designed, which can give an exact state estimate for linear time-invariant systems with unknown inputs. Specifically, it is a group of sensors with complementary measurement capabilities, in which each one serves as a local observer and has communication links with neighbors. Such networked sensor nodes are designed to cooperate by taking complementary actions, so that each one can estimate the full state of the plant exactly. The fully distributed design in this paper requires no global information such as the communication topology, collective measurement capability, and bound of the unknown input.

Magneto-structural characterization of different kinds of magnetic nanoparticles

Using well-established measurement techniques like transmission electron microscopy (TEM), dynamic light scattering (DLS), small and wide angle X-ray scattering (SAXS, WAXS), susceptometry, and magnetorelaxometry, the distribution of the physical and magnetic size (magnetic moments) and magnetic anisotropy of a variety of structurally different magnetic nanoparticle samples (MNPs) is analyzed and compared. A term which accounts for the presence of weak magnetic areas (WMAs) within the MNPs was introduced to the widespread analysis model for M(H) data, enabling a consistent interpretation of the data in most of the systems. A comparison of the size distributions as obtained for the physical and the magnetic diameter suggests a multidomain structure for three single core systems under investigation, in all probability evoked by the presence of a wustite phase, as identified by WAXS.Analyzing the relationship d < dm < dc between the average single core diameter d, the effective magnetic (domain) size dm and the cluster diameter dc quantitatively, two qualitatively different magnetic structures in multicore MNP (MCMNP) systems were identified: (i) The magnetic moments of single cores within the MCMNP of fluidMAG tend to build flux closure structures, driven by dipole–dipole interaction. (ii) The magnetic behavior of Resovist® was attributed to the presence of domain sizes of about 12 nm within MCMNP, exceeding the single core diameters of 5 nm. Thereby, WAXS revealed a bimodal crystallite size distribution suggesting a crystallite merging process within the MCMNP. The value of the effective magnetic moment of these MCMNP could be explained within the presented “random moment cluster model” (RMCM).We conclude that the combination of physical and magnetic structure parameters obtained from complementary measurement methods allows a reliable assessment of the magnetic structure of single and multicore MNPs.

Resilience basins of complex systems: An application to prosumer impacts on power grids.

Comparable to the traditional notion of stability in system dynamics, resilience is typically measured in a way that assesses the quality of a system's response, for example, the speed of its recovery. We present a broadly applicable complementary measurement framework that quantifies resilience similarly to basin stability by estimating a resilience basin, which reflects the extent of adverse influences that the system can recover from in a sufficient manner. In contrast to basin stability, the adverse influences considered here are not necessarily displacements in state space, but arbitrarily complex impacts to the system, quantified by adequate parameters. As a proof of concept, we present two applications: (i) the well-studied single-node power system as an easy-to-follow example and (ii) a stochastic model of a low-voltage DC power grid undergoing an unregulated energy transition consisting in the random appearance of prosumers. These act as decentral suppliers of photovoltaic power and alter the flow patterns while the grid topology remains unchanged. The resilience measurement framework is applied to evaluate the effect and efficiency of two response options: (i) upgrading the capacity of existing power lines and (ii) installing batteries in the prosumer households. The framework demonstrates that line upgrades can provide potentially unlimited resilience against energy decentralization, while household batteries are inherently limited (achieving ≤70% of the resilience of line upgrades). Further, the framework aids in optimizing budget efficiency by pointing toward threshold budget values as well as budget-dependent ideal strategies for the allocation of line upgrades and for the battery charging algorithm.

Self-assembly modulation in star block copolymers by amphiphilic diol: A scattering insight

The present study offers a better insight into the alteration in the aggregation characteristics of ethylene oxide-propylene oxide (EO-PO)-based star block copolymers Tetronics® T1304 and T1307 induced by an amphiphilic diol Surfynol® 104 (hereafter C14 diol) using scattering (dynamic light scattering and small angle neutron scattering) with complementary physical property measurement viz. solution viscosity and cloud point (CP). It is the hydrophobic interaction that drives C14 diol molecules to penetrate inside copolymer micelles resulting in dehydration that lowered the CP and markedly increase in solution viscosity. Quite interestingly, initial lowering in CP is followed by sudden increase at higher level of solubilization. A significant increase in the apparent hydrodynamic diameter (Dh) divulges the growth of micelles which is equally supported by SANS measurements. The micellar parameters obtained from SANS analysis for T1304 and T1307 in the presence of C14 diol are described. The preferential partitioning of C14 diol into the copolymer micelles is the driving force for morphological changes from spherical to unilamellar vesicles. Also, the effect of temperature and NaCl was examined with the aim to observe various micellar transitions. The observed changes are clarified in terms of the hydrophobic interaction of C14 diol with Tetronic® micelles and HLB value of copolymers. The perception of C14 diol stabilised Tetronic® micelles is anticipated and correlated with optimal parameters obtained from computational simulation approach, providing a clear understanding of the correlation between the molecular orbital energy levels of Tetronic® and C14 diol. The present manuscript thus sheds light on C14 diol induced dehydration causing the micelle growth for both Tetronics® with varied hydrophobicity. Such hydrophobic diol-induced spherical to vesicular transition is observed for the first time in Tetronic®-diol mixed system.