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Jack F. Douglas, Andrea Giuntoli, Francesco Puosi, Dino Leporini, Francis W. Starr
We examine the influence of steady shear on structural relaxation in a model coarse-grained unentagled polymer melt over a wide range of temperature and shear rates. Shear is found to progressively suppress the α-relaxation process observed in the
M. Waschk, A. Sarkar, J. Barthel, J. Voigt, S. Schroder, P. Zakalek, M. Schmitz, Brian Kirby, S. Putter, J. Schubert, T. Bruckel
The ability to create atomically perfect, epitaxial heterostructures of correlated complex perovskite oxides using state-of-art thin film deposition techniques has generated new physical phenomena at engineered interfaces. Here we report on the impact of
Bai-Qiao Song, Qing-Yuan Yang, Shi-Qiang Wang, Matthias Vandichel, Amrit Kumar, Clare Crowley, Naveen Kumar, Cheng-Hua Deng, Victoria GasconPerez, Matteo Lusi, Hui Wu, Wei Zhou, Michael J. Zaworotko
Closed-to-open structural transformations in flexible coordination networks are of interest for their potential utility in gas storage and separation. Herein, we report the first example of a flexible SiF 6 2--pillared square grid material, [Cu(SiF 6)(L) 2
Storing hydrogen efficiently in condensed material under mild conditions is a key technique challenge. Here, we developed a new family of hydrogen storage material spanning across the domain of inorganic and organic hydrides, namely metalorganic hydrides
We perform a systematic study of thermal resistance/conductance of tilt grain boundaries (GBs) in Si using classical molecular dynamics. The GBs studied are naturally divided into three groups according to the structural units forming the GB core. We find
Yingxiang Ye, Rui-Biao Lin, Hui Cui, Ali Alsalme, Wei Zhou, Taner N. Yildirim, Zhangjing Zhang, Shengchang Xiang, Banglin Chen
We reported a microporous MOF FJU-101 with open naphthalene diimide functional groups for room temperature (RT) high methane storage. At RT and 65 bar, the total volumetric CH 4 storage capacity of 212 cm -3 in FJU-101a is significantly higher than the
Many measurements have indicated that thin polymer films in their glass state exhibit an interfacial layer of enhanced mobility that grows in thickness upon heating, as found also in crystalline materials approaching their melting temperature Tm, while
Amy E. Engelbrecht-Wiggans, Ajay Krishnamurthy, Lucas H. Kaplan, Amanda L. Forster, Thanh N. Hoang, Viviana Bentley
Traditionally, soft body armor has been made from materials such as poly(p-phenylene terephthalamide) (PPTA) and ultra-high molar mass polyethylene (UHMMPE). However, to diversify the fiber choices in the United States body armor market, copolymer fibers
For glass-forming polymers, direct quantitative comparison of atomistically detailed molecular dynamics simulations with thermomechanical experiments is hindered by the vast mismatch between the accessible timescales. Recently, we demonstrated the
Matthew R. Rosenberger, Hsun-Jen Chuang, Vladimir Oleshko, Madeleine Phillips, Kathleen M. McCreary, Saujan V. Sivaram, C. Stephen Hellberg, Berend T. Jonker
Van der Waals layered materials, such as the transition metal dichalcogenides (TMDs), are an exciting class of materials with weak interlayer bonding which enables one to create so-called van der Waals heterostructures (vdWH). One promising attribute of
Ann C. Chiaramonti Debay, Luis Miaja Avila, Benjamin W. Caplins, Paul T. Blanchard, Norman A. Sanford, Brian Gorman, David R. Diercks
This paper reports construction of an extreme ultraviolet (EUV) radiation-triggered atom probe tomograph and describes the results from initial experiments on amorphous SiO2. Femtosecond-pulsed coherent EUV radiation of 29.6 nm wavelength (41.85 eV photon
Sonal Bhadauriya, Jianan Zhang, Jaejun Lee, Michael R. Bockstaller, Alamgir Karim, Richard J. Sheridan, Christopher Stafford
We combine in-situ heated atomic force microscopy (AFM) with automated line-by-line spectral analysis to quantify the relaxation or decay of nanopatterned polymer films at temperatures above the glass transition. This approach enables assessment of pattern
Sindhu Seethamraju, Jan Obrzut, Jack F. Douglas, Jeremiah Woodcock, Jeffrey W. Gilman
We investigated a chemically modified Rhodamine B dye as a sensor of local water content in dye-modified epoxy resins, where these measurements were combined with dielectric measurements to estimate the dye-water association ratio in the material. In
Joel M. Sarapas, Tyler B. Martin, Alexandros Chremos, Jack F. Douglas, Kathryn L. Beers
Many naturally occurring polyelectrolytes of importance in diverse biological functions have the form of bottlebrush polymers, and there is correspondingly widespread interest in the synthesis and characterization of bottlebrush polymers to capitalize on
Solid state refrigeration based on caloric effect has been regarded as an attractive alternative to conventional gas compression technique. Boosting the caloric effect of a system to its optimum is a long-term pursuit. Here, we report enhanced
Nicos Martys, Jeffrey W. Bullard, Pan Feng, Shaoxiong Ye
Solution flow profiles near a mineral surface can have significant influences on the local thermodynamic driving force and, potentially, the rate-controlling kinetic mechanism of its dissolution or precipitation. These influences are investigated here both
The C 2H 2/CO 2 separation is particularly challenging owing to their high similarity in physical properties and molecular sizes, but of industrial significance. Herein we report a mixed metal-organic framework (M'MOF) Fe(pyz)[Ni(CN) 4] (FeNi-M'MOF, pyz =
Vipul Chaturvedi, Jeff Walter, Arpita Paul, Alexander Grutter, Brian Kirby, Jong Seok Jeong, Hua Zhou, Zhan Zhang, Biqiong Yu, Martin Greven, K. Andre Mkhoyan, Turan Birol, Chris Leighton
Tensile-strained LaCoO 3-δ thin films are ferromagnetic, in sharp contrast to the zero-spin bulk, although no clear consensus has emerged as to the origin of this phenomenon. While magnetism has been heavily studied, relatively little attention has been
Negative thermal expansion (NTE) has emerged as one of intense research topics to meet the demands of precision industry for compensating positive thermal expansion (PTE) properties. The adjustment of NTE behavior is the key for tailoring thermal expansion
Hayden A Evans, Yue Wu, Ram Seshadri, Anthony K. Cheetham
ReO 3-type structures can be described as ABX 3 perovskites in which the A-cation site is unoccupied. They therefore have the general composition BX 3, where B is normally a cation and X is a bridging anion. The chemical diversity of such structures is
Wen-Yuan Pei, Jin Yang, Hui Wu, Wei Zhou, Ying-Wei Yang, Jian-Fang Ma
For self-assembly of large multi-component coordination cages, the difficulty increases substantially as the number of components increases. Judicious choice of the ancillary ligand with desired structural features provides an efficient design strategy for
Jiyan Pei, Jia-Xin Wang, Kai Shao, Yu Yang, Yuanjing Cui, Hui Wu, Wei Zhou, Bin Li, Guodong Qian
Realization of ethane-trapping materials for separating ethane (C 2H 6) from ethylene (C 2H 4) by adsorption, to potentially replace the energy-intensive cryogenic distillation technology, is of prime importance in the petrochemical industry. It is still
Kyoung-Il Jo, Younghoon Oh, Bong June Sung, Tae-Ho Kim, Min Seop Um, Woo Jin Choi, Joona Bang, Guangcui Yuan, Sushil K. Satija, Jaseung Koo
For polymer-blend films, local dynamics in confined polymer domains tend to differ from the bulk due to significant contributions from the polymer-polymer interface. Herein, we investigated the diffusion dynamics of entangled polymer thin films confined
Twenty years ago, research involving ionic liquids was a minor field of interest and only a few chemists and even fewer engineers were interested in salts with melting points near room temperature. In April 2000, the first NATO advanced research workshop