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Aaron M. Forster, Diane Mauchant, Elizabeth Wailes, Amanda L. Forster, Michael A. Riley, Kirk D. Rice
Polymer foams serve an important role in the assessment and certification of stab resistant body armor for both US and UK standards. A composite of neoprene and polyethylene foam is used behind the armor during testing. The foam mimics stab dynamics by
Jun Y. Chung, Adam J. Nolte, Christopher M. Stafford
Surface instabilities in soft matter have captivated the scientific community for decades. Recently, surface wrinkling has received a great deal of attention due to its simplicity and well-established mechanics of formation. Particularly, the use of
Yajun Cheng, Xinran Zhang, Diana N. Zeiger, Nancy Lin, Joseph M. Antonucci, Sheng Lin-Gibson
Polymeric nanocomposites containing silver are known to exhibit antibacterial activity. Here we demonstrate the synthesis and characterization of dimethacrylate/silver nanocomposites by coupling photopolymerization with in situ silver ion reduction. An
Yifu Ding, Jirun Sun, Hyun W. Ro, Zhen Wang, Jing N. Zhou, Nancy J. Lin, Sheng Lin-Gibson, Marcus T. Cicerone, Christopher L. Soles
Cells sense and respond to the chemical, topographical, and mechanical features of their substrate and extracellular matrix. Shape and locomotive response to these features is termed contact guidance (CG) and is of vital importance in understanding many
Jessica M. Torres, Christopher Stafford, Bryan D. Vogt
The mechanical stability of polymeric nanostructures is critical to the processing, assembly and performance of numerous existing and emerging technologies. A key predictor of mechanical stability is the elastic modulus. However, a significant reduction in
Debra Vazquez, Shozo Takagi, Stanislav Frukhtbeyn, Laurence Chow
The bone defect repair functions of calcium phosphate cement (CPC) are related to its osteoconductivity and its gradual replacement by new bone. Adding mannitol to CPC may enhance its bone repair potential by increasing CPCs macroporosity and dissolution
Shozo Takagi, Stanislav A. Frukhtbeyn, Laurence C. Chow, Akiyoshi Sugawara, Kenji Fujikawa, Kidehiro Ogata, Makoto Hayashi, Bunnai Ogiso
This study reports for the first time in vitro and in vivo properties of fluorapatite (FA)-forming calcium phosphate cements (CPCs). The experimental cements contained from (0 to 3.3) mass % of F, corresponding to presence of FA at levels of approximately
The present study evaluated characteristics of premixed calcium phosphate cements (Pre-CPCs) when implanted in subcutaneous tissues (Study I) and used for repairing surgically created two-wall periodontal defects (Study II). Pre-CPC pastes were prepared by
Jessica M. Torres, Christopher Stafford, Bryan D. Vogt
Euler wrinkling was used to determine the elastic modulus at ambient temperature of polystyrene (PS) films of varying thickness and relative molecular mass (Mn). A range of Mn from 1.2 kg/mol to 990 kg/mol was examined to determine if the molecular size
Polymer coatings are dependent on strongly bonded buried interfaces to maintain adhesion and protective properties over long application lifetimes. In this work, we detail the detection of buried interfaces with deviations from perfect bonded or perfect
Kaushik Chatterjee, Sheng Lin-Gibson, William E. Wallace, Marian F. Young, Carl Simon Jr.
A combinatorial library approach was used to demonstrate that hydrogel scaffold modulus can enhance osteoblast differentiation driving formation of a 3-D graded tissue construct. Though many previous studies have focused on screening cell-material
The ability to force immiscible polymers into specific, targeted structures would enable the generation of blends with tailored performance by exploiting the intimate relationship between structure and blend properties. Here we present a strategy for the
While there are many societal and economic factors that contribute to a sustainable civilization, there are also real technical and scientific problems that must be solved to provide the materials necessary to make progress towards the goal of
This NIST Recommended Practice Guide presents a method using mass spectrometry to make a quantitative determination of the molecular mass distribution of narrow polydispersity synthetic molecular materials. The main obstacle for converting an oligomer
William E. Wallace, Lewandowski Hans, Meier J. Robert
Recently it has been shown that the cobaltocenium cation, prepared by the laser ablation of a CoCp(CO)2/fullerene matrix, may react with alkanes and polyethylenes in the gas phase via a dehydrogenation reaction to produce [Co(Cp)2(alkadiene)]+ ions without
The osteoconductive and possibly osteoinductive characteristics of OCP increased the interest in preparation of bone graft materials that contain OCP in its composition. Calcium phosphate cements (CPCs) were prepared using a mixture of α tricalcium
Atif A. Imtiaz, Thomas M. Wallis, SangHyun S. Lim, Jonathan Chisum, Zoya Popovic, Pavel Kabos
The Scanning Microwave Probe (SMP) is emerging as an important broadband metrology tool for characterizing the materials and devices in the micron and sub-micron length scales in the frequency range of 10 MHz to 110 GHz. In this document we establish three
A previously reported, premixed calcium phosphate cements (CPC) forms hydroxyapatite (HA) as the only product, but had a setting time greater than 60 min. This study investigated properties of fast-hardening HA-forming premixed CPCs. All cements consisted
Christopher M. Stafford, Adam J. Nolte, Gale A. Holmes, Sheng Lin-Gibson, John A. Howarter
NIST s involvement in adhesion research has been wide ranging and is ultimately in response to interactions between individual project leaders and our industrial partners. In this way, NIST s participation in the Adhesion Society has been instrumental in
Nancy Lin, Joseph M. Antonucci, Diana N. Zeiger, Kathy Tang, Bruce O. Fowler, Sheng Lin-Gibson
Biofilm growth and secondary caries have resulted in the failure of many dental composite restorations. One approach to address this issue is the modification of dental materials to reduce bacterial adhesion and biofilm growth. Quaternary ammonium salts
Erik K. Hobbie, Daneesh O. Simien, Jeffrey A. Fagan, JiYeon Huh, Jun Y. Chung, Steven D. Hudson, Jan Obrzut, Jack F. Douglas, Christopher M. Stafford
Ultrathin layers of single-wall carbon nanotubes (SWCNTs) show considerable promise for applications ranging from fuel-cell membranes and biochemical sensors to bioactive films and transparent electrodes. The high conductivity and extreme anisotropy of
Compressive stresses in stiff polymer coatings can give rise to surface instabilities in which the coating adopts a sinusoidally wrinkled morphology with a dominant wavelength, d, as displayed in Figure 1a. Such instabilities are generally observed for
Jessica M. Torres, Christopher Stafford, Bryan D. Vogt
In this work, we examine the influence of relative molecular mass (Mn, or the number average molecular mass) of PS on the thickness-dependent moduli using a wrinkling based instability of a stiff film on an elastic substrate. This wrinkling based metrology