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Displaying 651 - 675 of 1856

Metrology for 3D Integration

May 13, 2014
Author(s)
Richard A. Allen, Victor H. Vartanian, David T. Read, Winthrop A. Baylies
Three-dimensional stacked integrated circuit (3DS-IC) fabrication requires complex technologies such as high-aspect ratio through- silicon vias (TSVs), wafer thinning, thin wafer handling and processing, and bonding of thin wafers with complex patterned

DNA-based Nanocomposite Bio-Coatings for Fire Retarding Polyurethane Foam

May 2, 2014
Author(s)
Yu-Chin Li, Yeon S. Kim, John R. Shields, Rick D. Davis
Layer-by-Layer (LbL) assembled multilayer thin films of deoxyribonucleic acid (DNA), chitosan (CHI), and montmorillonite (MMT), were studied in an effort to produce fully renewable, bio-based fire retardant coatings for flexible polyurethane foam. The PUF

Accurate RRAM Transient Currents during Forming

April 30, 2014
Author(s)
Pragya R. Shrestha, David M. Nminibapiel, Jason P. Campbell, Jihong Kim, Canute I. Vaz, Kin P. Cheung, Helmut Baumgart
Current overshoot during forming has been shown to be a serious issue. Recently the current overshoot duration has been shown to be an important factor impacting device performance. Short duration overshoot in the range of ns yield better performance. But

Tearing and scrolling of transferred graphene

April 29, 2014
Author(s)
Guangjun Cheng, Brent A. Sperling, James E. Maslar, Curt A. Richter, Angela R. Hight Walker
We present an investigation on tearing and scrolling of the transferred graphene on a Si/SiO2 substrate. Graphene grown by chemical vapor deposition (CVD) is transferred onto a Si/SiO2 substrate using a wet polymer-mediated process. Upon the removal of

Confinement-Driven Increase in Ionomer Thin-Film Modulus

April 28, 2014
Author(s)
Kirt A. Page, Ahmet Kusoglu, Christopher M. Stafford, Sangcheol Kim, Regis J. Kline, Adam Weber
Ion-conductive polymers, or ionomers, are critical materials for a wide range of electrochemical technologies. For optimizing the complex, heterogeneous structures in which they occur, there is a need to elucidate the governing structure/function

NIST Micronutrients Measurement Quality Assurance Program Winter, Spring, and Fall 1995 Comparability Studies: Results for Round Robins XXXIII, XXXIV, and XXXV Fat-Soluble Vitamins and Carotenoids in Human Serum and Round Robins 7 and 8 Ascorbic Acid in H

April 25, 2014
Author(s)
David L. Duewer, Margaret C. Kline, Katherine E. Sharpless, Jeanice M. Brown Thomas, Sam A. Margolis
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes

Combinatorial Cassette for Screening of Osteogenesis by Transplanted Human Bone Marrow Stromal Cells

April 19, 2014
Author(s)
Subhadip Bodhak, Sheng Lin-Gibson, Carl G. Simon Jr., Luis Fernandez de Castro Diaz, Pamela G. Robey, Sergei A. Kuznetsov, Tina Kilts, Marian F. Young
The use of in vivo transplantation assays under defined experimental conditions has become a valuable standard for evaluating osteogenic potential of different stem cell populations and is the subject of ongoing pre-clinical reconstructive therapy research

Evaluation of the effect of donor variability on stem cell response to biomaterials

April 19, 2014
Author(s)
Stephen J. Florczyk, Bryan A. Baker, Sumona Sarkar, Jennifer H. McDaniel, Patrick S. Pine, Marc L. Salit, Carl G. Simon Jr.
Previous research from our group indicated that nanofiber scaffolds promoted osteogenic differentiation of human bone marrow stromal cells (hBMSC) and similar gene expression to osteogenic supplement (OS) induced osteogenic differentiation [1]. Biological

Measuring Organelle Shape in 3D in Stem Cells Cultured on Nanofiber Scaffolds

April 19, 2014
Author(s)
Carl G. Simon Jr., Peter Bajcsy, Wojtek J. Tutak, Jyotsnendu J. Giri
Previous work has demonstrated that culture of osteoprogenitor cells on nanofiber scaffolds can potentiate osteogenic differentiation [1-4]. Culture of cells in nanofiber scaffolds causes changes to cell morphology, suggesting that morphological changes

A Quantitative Study of Nanoparticle Release from Nanocoatings Exposed to UV Radiation

April 7, 2014
Author(s)
Li Piin Sung, Deborah S. Jacobs, Justin M. Gorham, Savelas A. Rabb, Xiaohong Gu, Lee L. Yu, Tinh Nguyen
Nanoparticles are increasingly used in polymer coatings (i.e., nanocoatings) to improve multiple properties of traditional coatings such as mechanical, electrical, gas barrier, and UV resistance. These high performance nanocoatings are often used in

Measuring Stem Cell Dimensionality in Tissue Scaffolds

April 1, 2014
Author(s)
Carl G. Simon Jr., Sapun Parekh, Christopher K. Tison, Girish Kumar, Tanya M. Farooque, Charles H. Camp
Many 3D scaffold systems have evolved for tissue engineering, drug screening and in vitro tissue models. However, it is not clear which scaffolds provide a 3D cell niche and there is no clear way to measure cell niche dimensionality. Advances in 3D niche

Twin Plane Re-entrant Mechanism for Catalytic Nanowire Growth

March 12, 2014
Author(s)
Andrew D. Gamalski, Peter W. Voorhees, Renu Sharma, Caterina Ducati, Stephan Hofmann
We observe a twin plane re-entrant based growth mechanism for Au catalyzed Ge nanowire growth using video-rate lattice-resolved environmental transmission electron microscopy. For a [112] growth direction, we find a convex, V-shaped liquid catalyst

Characterization of InGaN quantum disks in GaN nanowires

March 4, 2014
Author(s)
Alexana Roshko, Roy H. Geiss, John B. Schlager, Matthew D. Brubaker, Kristine A. Bertness, Norman A. Sanford, Todd E. Harvey
Catalyst-free GaN nanowires with InGaN quantum disks (QDs) were characterized by scanning/transmission elec-tron microscopy (S/TEM) and photoluminescence. A va-riety of structures, from QDs with large strain fields to apparently strain free QDs were

Constant Shape Factor Frequency Modulated Charge Pumping (FMCP)

March 3, 2014
Author(s)
Jason T. Ryan, Jason P. Campbell, Jibin Zou, Kin P. Cheung, Richard Southwick, Anthony Oates, Rue Huang
Abstract— We examine the seemingly frequency-dependent gate leakage current component of frequency-modulated charge pumping and show it to be a measurement artifact. If untreated, this results in erroneous defect density extractions. We present a constant

Dependence of the Filament Resistance on the Duration of Current Overshoot

March 3, 2014
Author(s)
Pragya R. Shrestha, David M. Nminibapiel, Jason P. Campbell, Kin P. Cheung, Helmut Baumgart, Shweta Deora, G. Bersuker
The characteristics of a conductive filament in HfO2 RRAM is shown to be dependent on the duration of the current compliance overshoot, which may occur during the filament formation process. In addition to the overshoot amplitude, the filament resistance

Fast-Capacitance for Advanced Device Characterization

March 3, 2014
Author(s)
Pragya R. Shrestha, Kin P. Cheung, Jason T. Ryan, Jason P. Campbell, Helmut Baumgart
Fast-CV measurements are frequently being used to study transient phenomena associated with advanced devices. In this study, we show that many artifacts plague this measurement and then provide a proper method to legitimize fast-CV measurements as

Effects of nanoparticle size and charge on interactions with self-assembled collagen

March 1, 2014
Author(s)
Dongbo Wang, Jing (. Ye, Steven Hudson, Keana Scott, Sheng Lin-Gibson
Recent insights into bone formation have suggested that the critical first step to the biomineralization process is the integration of small (nanometer dimension) mineral clusters into collagen fibers. Such behavior is of intrinsic interest for the areas

Laser-assisted atom probe tomography of MBE grown GaN nanowire heterostructures

February 24, 2014
Author(s)
Norman A. Sanford, Paul T. Blanchard, Matthew D. Brubaker, Kristine A. Bertness, John B. Schlager, R Kirchofer, David R. Diercks, Brian Gorman
Laser-assisted atom probe tomography (L-APT) was performed on GaN nanowires (NWs) and axial GaN/InGaN nanowire heterostructures. All samples were grown by MBE on Si(111) substrates. The laser pulse energy (PE) at 355 nm used in L-APT analysis of GaN NWs

Structure-Property Relationships in Polyethylene Fusion Bonds

February 24, 2014
Author(s)
Aaron M. Forster, Kar T. Tan, Wei-Lun Ho, Donald L. Hunston
Polyethylene (PE) is used significantly for a wide range of critical fluid transport applications from water to fossil fuels. The advantages of polyethylene are competi-tive cost compared to metallic pipe, lower corrosion rates, and toughness. The key to

Inverse Vulcanization of Elemental Sulfur to Prepare Polymeric Electrode Materials for Li-S Batteries

February 20, 2014
Author(s)
Christopher L. Soles, Vladimir P. Oleshko, Jenny J. Kim, Adam Simmonds, Jared Griebel, Jeff Pyun, Jungjin Park, Woo Jin Chung, Woo Tae Kim, Richard Glass, Yung-Eun Sun, Kookheon Char
Sulfur-rich copolymers were synthesized via inverse vulcanization to create electroactive cathode materials for lithium-sulfur battery applications. These materials exhibit enhanced capacity retention (1005 mAh/g at 100 cycles) and extended battery

Top-Down Fabrication of Large-Area GaN Micro and Nano Pillars

February 19, 2014
Author(s)
Albert Davydov, Ratan K. Debnath, B. Wen, Dipak Paramanik, Abhishek Motayed, M. King
Large-area gallim nitride (GaN) nanopillars (NPs) arrays were fabricated by plasma etching of lithographically patterned GaN thin-film grown on Si substrate. Deep-UV lithography, inductively-coupled plasma etching, and follow-on chemical treatments were
Displaying 651 - 675 of 1856