Read by QxMD icon Read

Langmuir: the ACS Journal of Surfaces and Colloids

Zhen Chen, Duyang Zang, Liang Zhao, Mengfei Qu, Xu Li, Xiaoguang Li, Lixin Li, Xingguo Geng
Liquid marbles show promising potential application in the microreactor field. It is of great importance to control the coalescence between two or multiple liquid marbles, however, it is highly difficult to successfully merge two isolated marbles due to their mechanically robust particle shells. In this work, we accomplished the coalescence of multiple liquid marbles via acoustic levitation. The dynamic behaviors of the liquid marbles were monitored by a high-speed camera to find that driven by the sound field, the liquid marbles moved towards each other, collided, and eventually coalesced into a larger single marble...
March 24, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Nandi Vrancken, Stefanie Sergeant, Guy Vereecke, Geert Doumen, Frank Holsteyns, Herman Terryn, Stefan De Gendt, XiuMei Xu
In situ characterization of the underwater stability of superhydrophobic micro- and nanostructured surfaces is important for the development of self-cleaning and anti-fouling materials. In this work, we demonstrate a novel ATR-FTIR (Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy) based method for large-area wetting characterization of silicon nanopillars. When air is present in between the structures, as is characteristic of the Cassie-Baxter state, the relative intensities of the water bands in the absorption spectrum are changed due to the wavelength-dependent attenuation of the evanescent wave...
March 24, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Shuaidi Zhang, Sunghan Kim, Vladimir V Tsukruk
We report direct high-resolution monitoring of an evolving mixed nanodomain surface morphology during thiol adsorption on polyvinylpyrrolidone (PVP)-stabilized single crystal gold nanocrystals. The thiol adsorption and replacement dynamics are found to be much more complex than a simple complete substitution of the initial polymer ligand. We observed that during ligand exchange with linear thiol, the nanocrystal surface evolved from an initial 1 nm uniform PVP coating into a remarkably stable network of globular PVP domains 20-100 nm in size and ~4 nm in height surrounded by thiol self-assembled monolayers (SAMs)...
March 24, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Gildas Nyame Mendendy Boussambe, Romain Valentin, Jean-François Fabre, Laurence Navailles, Frédéric Nallet, Cédric Gaillard, Zéphirin Mouloungui
The self-assembling properties of glycerol esters in water are well known. Still, few data on glycerol monoesters of undecylenic acid are available. The aim of this study was to highlight the behavior of glycerol monoundecenoate (GM-C11:1) in different diluted and concentrated states. Its self-assembling properties in water and upon solid inorganic surfaces were investigated in the diluted state using surface tension experiments, atomic force microscopy, and cryogenic transmission electron microscopy studies...
March 24, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Po-Wei Yang, Subashchandrabose Thoka, Po-Chang Lin, Chun-Jen Su, Hwo-Shuenn Sheu, Michael H Huang, U-Ser Jeng
The nucleation and growth process of gold supercrystals in a surfactant diffusion approach is followed by simultaneous small- and wide-angle X-ray scattering (SAXS/WAXS), supplemented with scanning electron microscopy. The results indicate that supercrystal nucleation can be activated efficiently upon placing a concentrated surfactant solution of a nematic phase on top of a gold nanocrystal solution droplet trapped in the middle of a vertically oriented capillary tube. Supercrystal nuclei comprised of tens of gold nanocubes are observed nearly instantaneously in the broadened liquid-liquid interface zone of a steep gradient of surfactant concentration, revealing a diffusion-kinetics-controlled nucleation process...
March 24, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Fan Wu, De-Wen Zhang, Jian Wang, Michael Watkinson, Steffi Krause
A copper(I)-catalyzed azide alkyne cycloaddition (CuAAC) reaction combined with microcontact printing was used successfully to pattern alkyne-terminated self-assembled organic monolayer-modified silicon surfaces. Despite the absence of a copper peak in X-ray photoelectron spectra, copper contamination was found and visualized using light-addressable potentiometric sensors (LAPS) and scanning photo-induced impedance microscopy (SPIM) after the "click"-modified silicon surfaces were rinsed with hydrochloric acid (HCl) solution, which was frequently used to remove copper residues in the past...
March 24, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Chaitanya Narayanam, Avanish Kumar, Sanjay Puri, Rajesh Khanna
Unstable thin films can spontaneously phase separate into two equilibrium flat-film morphologies of different thicknesses under the influence of gravity or favorable combinations of apolar and polar excess intermolecular forces. Two distinct pathways and associated dynamics of this morphological phase separation are presented based on numerical simulations of the 2-D thin film equation. The two pathways are (1) the "direct pathway" whereby the thicker phase forms directly and concurrently with the thinner phase and (2) the "defect pathway" whereby the thicker phase forms by the coarsening of defects of intermediate thickness and appears much later than the thinner phase...
March 24, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Aibin Huang, Lei Lei, Jingting Zhu, Yu Yu, Yan Liu, Songwang Yang, Shanhu Bao, Xun Cao, Ping Jin
Aiming at fabricating simple, reproducible and scalable perovskite solar cells (PSCs) with least time consuming, novel CoOx hole transport layer (HTL) was first proposed and introduced in this work. The CoOx HTL thickness was minimized to about 10 nm with complete coverage on FTO substrate (F doped SnO2) by DC magnetron sputtering. The compact ultrathin HTL could minimize the incident light loss caused by cobalt ion absorption and reduce the carrier transport loss by shortening the transport path. Copper ion doping was employed to address the low conductivity of CoOx film and the energy level mismatch between CoOx and perovskite material...
March 23, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Line Koefoed, Steen U Pedersen, Kim Daasbjerg
The reduction of an aryl iodide is generally believed to involve a clean-cut two-electron reduction to produce an aryl anion and iodide. This is in contradiction to what is observed if a highly efficient grafting agent, such as an aryldiazonium salt, is employed. The difference in behavior is explained by the much more extreme potentials required for reducing an aryl iodide, which facilitates the further reduction of the aryl radical formed as an intermediate. However, in this study we disclose that electrografting of aryl iodides is indeed possible upon extended voltammetric cycling...
March 23, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Marta Orczyk, Kamil Wojciechowski, Gerald Brezesinski
Digitonin, a steroidal saponin obtained from the Foxglove plant (Digitalis purpurea), displays a wide spectrum of biological properties and is often used as a model in mechanistic investigations of biological activity of saponins. In the present study, Langmuir monolayers of zwitterionic (DPPC, DMPE, POPC, POPE, DSPC, DSPE, DPPE) and ionic (DPPS, DPPG) phospholipids were employed, in order to better understand the effect of digitonin on the lipid organization. For this purpose, a combination of surface pressure relaxation, infrared reflection absorption spectroscopy (IRRAS) and fluorescence microscopy measurements, was used...
March 23, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Martin E J Haagh, Igor Siretanu, Michael H G Duits, Frieder Mugele
The effectiveness of water flooding oil recovery depends to an important extent on the competitive wetting of oil and water on the solid rock matrix. Here, we use macroscopic contact angle goniometry in highly idealized model systems to evaluate how brine salinity affects the balance of wetting forces and to infer the microscopic origin of the resulting contact angle alteration. We focus in particular on two competing mechanisms debated in the literature, namely double layer expansion and divalent cation bridging...
March 23, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Mrinmoyee Basu, Roshan Nazir, Chavi Mahala, Pragati Fageria, Sumita Chaudhary, Subhashis Gangopadhyay, Surojit Pande
Different metal chalcogenides, being a potential candidate for hydrogen evolution catalysts, have attracted enormous attention in the field of water splitting. In the present study, Ag2S/Ag is revealed as an efficient catalyst for hydrogen evolution. When a sacrificial template of the CuS nanostructure is used, Ag2S/Ag heterostructures are synthesized following a simple wet-chemical technique. Two different routes, wet chemical and hydrothermal, are followed to modulate the morphology of the CuS templates from flower ball to wirelike structures, which subsequently results in the formation of Ag2S nanostructure...
March 23, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Pengfei Lv, Yu Liu, Zhe Wang, Shuyang Liu, Lanlan Jiang, Junlin Chen, Yongchen Song
The wettability of porous media is of major interest in a broad range of natural and engineering applications. The wettability of a fluid on a solid surface is usually evaluated by the contact angle between them. While in situ local contact angle measurements are complicated by the topology of porous media, which can make it difficult to use traditional methods, recent advances in microfocused X-ray computed tomography (micro-CT) and image processing techniques have made it possible to measure contact angles on the scale of the pore sizes in such media...
March 22, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Carlos A Orozco, Byong-Wa Zen Chun, Guoqing Geng, Abdul-Hamid Emwas, Paulo J M Monteiro
Major developments in concrete technology have been achieved with the use of polycarboxylate-based superplasticizers (PCEs) to improve the concrete rheology without increasing the mix water content. Currently, it is possible to control the fluidity of the fresh concrete and obtain stronger and more durable structures. Therefore, there is a strong incentive to understand the interactions between PCEs and cement hydrates at the atomic scale to design new customized functional PCEs according to the ever-increasing requirements of the concrete industry...
March 22, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Fan Xie, Congcong Zhuo, Chuanjiang Hu, Ming Hua Liu
While the sophisticated Langmuir and Langmuir-Blodgett technique facilitates the fabrication of uniform ultrathin monolayer and films, it is also revealed as a powerful tool for the bottom-up constructions of the nanostructures through the air/water interface. In this paper, unique nanoflowers or nanospheres were constructed based on the synthesized m-phthalic diamide-linked Zinc bis-porphyrinate tweezers using the Langmuir and Langmuir-Blodgett (LB) technique. It was found that both the two tweezer type Zinc bisporphyrinates could form stable two-dimensional spreading films at the air/water interface, which could be subsequently transferred onto solid substrates by the vertical lifting method...
March 22, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Elena Yu Kozhunova, Alexey A Gavrilov, Mikhail Yur'Evich Zaremski, Alexander V Chertovich
We explore the influence of a selective substrate on the composition and sequence statistics during the free radical copolymerization. In particular, we study the radical copolymerization of styrene and acrylic acid in bulk and in silica pores of different sizes. We show that the substrate affects both polymer composition and sequence statistics. We use dissipative particle dynamics simulations to study the polymerization process in detail, trying to pinpoint the parameters responsible for the observed differences in the polymer chain composition and sequences...
March 22, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Rui Zhang, Pengfei Hao, Feng He
This paper investigates the complex physical phenomenon of oblique drop impact on superhydrophobic substrates with two-tier roughness (patterned with varied submillimeter-scale posts and coated with nano-particles). Experimental results show that the impact Weber number of drops and the solid fraction of the submillimeter-scale post structures are crucial for the outcomes of oblique drop collisions. Water droplets with 10<Wen<245 are found to rebound on all the test substrates. As the surface solid fraction decreases, four possible bouncing patterns occur in sequence, sliding rebound, stretched rebound, penetration rebound and breakup rebound...
March 22, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Sonal Deshpande, Neetu Singh
Interaction of nanoparticles with biological systems is a key factor influencing their efficacy as a drug delivery vehicle. The inconsistency in defining the optimal design parameters across different nanoparticle types, suggests that information gained from one model system need not apply to other systems. Therefore, selection of a versatile model system is critical for such studies. Cubosomes are one of the potential drug delivery vehicles due to their biocompatibility, stability, ability to carry hydrophobic, hydrophilic and amphiphilic drugs and ease of surface modification...
March 21, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Timur R Galimzyanov, Anna S Lyushnyak, Veronika V Aleksandrova, Liudmila A Shilova, Ilya I Mikhalyov, Irina M Molotkovskaya, Sergey A Akimov, Oleg V Batishchev
Liquid-ordered lipid domains, also called rafts, are assumed to be important players in different cellular processes, mainly signal transduction and membrane trafficking. They are thicker than the disordered part of the membrane and are thought to form for compensating the hydrophobic mismatch between transmembrane proteins and lipid environment. Despite the existence of such structures in vivo is still an open question, they are observed in model systems of multicomponent lipid bilayers. Moreover, the predictions obtained from model experiments allow explaining different physiological processes possibly involving rafts...
March 21, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Raul Zazpe, Jan Prikryl, Viera Gärtnerova, Katerina Nechvilova, Ludvik Benes, Lukas Strizik, Ales Jäger, Markus Bosund, Hanna Sopha, Jan M Macak
We report on a very significant enhancement of the thermal, chemical, and mechanical stability of self-organized TiO2 nanotubes layers, provided by thin Al2O3 coatings of different thicknesses prepared by atomic layer deposition (ALD). TiO2 nanotube layers coated with Al2O3 coatings exhibit significantly improved thermal stability as illustrated by the preservation of the nanotubular structure upon annealing treatment at high temperatures (870 °C). In addition, a high anatase content is preserved in the nanotube layers against expectation of the total rutile conversion at such a high temperature...
March 21, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"