CRYSTALLINE NANO STRUCTURES

The present invention comprises nano obelisks and nanostructures and methods and processes for same. The nano obelisks of the present invention are advantageous structures for use as electron source emitters. For example, the ultra sharp obelisks can be used as an emitter source to generate highly coherent and high energy electrons with high current

Covalently Functionalized Nanotubes as Nanometer-Sized Probes in Chemistry and Biology

Carbon nanotubes combine a range of properties that make them well suited for use as probe tips in applications such as atomic force microscopy (AFM)1, 2, 3. Their high aspect ratio, for example, opens up the possibility of probing the deep crevices4 that occur in microelectronic circuits, and the small effective radius of nanotube tips significantly improves the lateral resolution beyond what can be achieved using commercial silicon tips5. Another characteristic feature of nanotubes is their ability to buckle elastically4, 6, which makes them very robust while limiting the maximum force that is applied to delicate organic and biological samples. Earlier investigations into the performance of nanotubes as scanning probe microscopy tips have focused on topographical imaging, but a potentially more significant issue is the question of whether nanotubes can be modified to create probes that can sense and manipulate matter at the molecular level7. Here we demonstrate that nanotube tips with the capability of chemical and biological discrimination can be created with acidic functionality and by coupling basic or hydrophobic functionalities or biomolecular probes to the carboxyl groups that are present at the open tip ends. We have used these modified nanotubes as AFM tips to titrate the acid and base groups, to image patterned samples based on molecular interactions, and to measure the binding force between single protein ligand pairs. As carboxyl groups are readily derivatized by a variety of reactions8, the preparation of a wide range of functionalized nanotube tips should be possible, thus creating molecular probes with potential applications in many areas of chemistry and biology.Chemistry and Chemical Biolog

SYNTHESIS OF CERIUM OXIDE NANORODS

Cerium oxide nanorods having a variety of aspect ratios can be produced by providing a first mixture that includes a cerium precursor material, and using microwave to heat the first mixture to a first temperature for a period of time to produce first plurality of cerium oxide nanorods having a first range of aspect ratios. A second mixture that includes a cerium precursor material heated using microwave to a second temperature for a period of time to produce second plurality of cerium oxide nanorods having a second range of aspect ratios. The first plurality of cerium oxide nanorods and the second plurality of cerium oxide nanorods are mixed to produce third plurality of cerium oxide nanorods having the third range of aspect ratios that is broader than the first range or the second range

Growth of carbon dioxide whiskers

We report the growth of carbon dioxide (CO2) whiskers at low temperatures (–70 °C to –65 °C) and moderate pressure (4.4 to 1.0 bar). Their axial growth was assessed by optical video analysis. The identities of these whiskers were confirmed as CO2 solids by Raman spectroscopy. A vapor– solid growth mechanism was proposed based on the influence of the relative humidity on the growth

Lateral growth of xenon hydrate films on mica

In this paper, we report an in situ optical microscopy study of lateral growth of xenon (Xe) hydrate thin films on mica at sub-zero temperatures. The interactions between a solid surface and water molecules can strongly affect the alignment of water molecules and induce ice-like ordered structures within the water layer at the water-surface interface. Mica was chosen as a model surface to study the surface effect of hydrophilic sheet silicates on the lateral growth of Xe hydrate films. Under the experimental conditions, the lateral growth of Xe hydrate films was measured to be at an average rapid rate of ~200 μm/s and 400 μm/s under two different pressures of Xe. Mass transfer estimation of the Xe-water system revealed that the increasing trend of lateral film growth rates followed the increase in the net mass flux and aqueous solubility of Xe. However, as the supercooling temperature increased, the trend of lateral film growth rates attained a plateau region where little change in the rate was observed. This unique feature in the lateral film growth trend, the fast lateral growth kinetics, and the short induction time for hydrate film growth hinted at the assistance of the mica surface to aid the lateral growth process of Xe hydrate films at low Xe mass flux and at a low degree of subcooling. A mechanism based on the reported structured water layer at the interface on mica was proposed to rationalize a postulated surface-promotional effect of mica on the nucleation and lateral growth kinetics of Xe hydrate films

METHODS OF MAKING AND USING LIGNIN DERIVATIVES

Materials and methods for preparing reactive lignin and for preparing a bio-based adhesive are described herein. This disclosure generally relates to methods of making and using reactive lignin. This disclosure also generally relates to methods of making and using bio-based adhesives. Lignin is the second most abundant natural polymer behind cellulose, yet lignin has very little commercial value despite years of research. Lignin is one of the major components of the cell wall in wood and other plant based materials such as hemp or crop wastes. It is produced in enormous quantities each year, primarily as a by-product in the pulp and paper industries. Lignin has little economic value and the majority of lignin is burned as a low grade fuel or is discharged into the aquatic ecosystem as waste, causing a significant impact on the environment. For example, the majority of the Biological Oxygen Demand (BOD) from pulp mill effluents is due to waste lignin. In addition, an increase in the production of cellulosic ethanol from corn stalk and other biomass resources will add significantly to this glut of lignin. This tremendous oversupply of lignin presents an enormous opportunity for the development of renewable biomaterials to replace non-biodegradable petroleum-based products, and the present disclosure provides for commercially-viable and inexpensive methods of making reactive lignin that can be used to make a wide variety of lignin-based products. In a similar vein, there is a growing demand for developing non-petroleum-based materials to replace traditional plastics. There is a critical need to replace the commonly used formaldehyde-based resins found in many building materials such as plywood and particle boards. Formaldehyde-based resins have raised alarming health concerns because formaldehyde is highly toxic, allergenic and a classified carcinogenic. The off-gassing of formaldehyde-based resins is a significant source of indoor air pollution, particularly from formaldehyde pressed-wood products. Thus, this disclosure also describes the development of a class of formaldehyde-free, bio-based reactive adhesives for binding renewable biodegradable material such as lignin, cellulose, wood chips and crop waste to fabricate useful solid materials and composites

METHODS OF MAKING AND USING LIGNIN DERIVATIVES

Materials and methods for preparing reactive lignin and for preparing a bio-based adhesive are described herein. This disclosure generally relates to methods of making and using reactive lignin. This disclosure also generally relates to methods of making and using bio-based adhesives. Lignin is the second most abundant natural polymer behind cellulose, yet lignin has very little commercial value despite years of research. Lignin is one of the major components of the cell wall in wood and other plant based materials such as hemp or crop wastes. It is produced in enormous quantities each year, primarily as a by-product in the pulp and paper industries. Lignin has little economic value and the majority of lignin is burned as a low grade fuel or is discharged into the aquatic ecosystem as waste, causing a significant impact on the environment. For example, the majority of the Biological Oxygen Demand (BOD) from pulp mill effluents is due to waste lignin. In addition, an increase in the production of cellulosic ethanol from corn stalk and other biomass resources will add significantly to this glut of lignin. This tremendous oversupply of lignin presents an enormous opportunity for the development of renewable biomaterials to replace non-biodegradable petroleum-based products, and the present disclosure provides for commercially-viable and inexpensive methods of making reactive lignin that can be used to make a wide variety of lignin-based products. In a similar vein, there is a growing demand for developing non-petroleum-based materials to replace traditional plastics. There is a critical need to replace the commonly used formaldehyde-based resins found in many building materials such as plywood and particle boards. Formaldehyde-based resins have raised alarming health concerns because formaldehyde is highly toxic, allergenic and a classified carcinogenic. The off-gassing of formaldehyde-based resins is a significant source of indoor air pollution, particularly from formaldehyde pressed-wood products. Thus, this disclosure also describes the development of a class of formaldehyde-free, bio-based reactive adhesives for binding renewable biodegradable material such as lignin, cellulose, wood chips and crop waste to fabricate useful solid materials and composites

SYNTHESIS OF CERIUM OXIDE NANORODS

Cerium oxide nanorods having a variety of aspect ratios can be produced by providing a first mixture that includes a cerium precursor material, and using microwave to heat the first mixture to a first temperature for a period of time to produce first plurality of cerium oxide nanorods having a first range of aspect ratios. A second mixture that includes a cerium precursor material heated using microwave to a second temperature for a period of time to produce second plurality of cerium oxide nanorods having a second range of aspect ratios. The first plurality of cerium oxide nanorods and the second plurality of cerium oxide nanorods are mixed to produce third plurality of cerium oxide nanorods having the third range of aspect ratios that is broader than the first range or the second range

BIOADHESIVES

Materials and methods for preparing reactive lignin and for preparing a bio - based adhesive are described herein

Characterization of three-dimensional fractional viscoelastic models through complex modulus analysis and polar decomposition

Soft materials such as gels, elastomers, and biological tissues have diverse applications in nature and technology due to their viscoelastic nature. These soft materials often exhibit complex rheology and display elastic and viscous characteristics when undergoing deformation. In recent years, fractional calculus has emerged as a promising tool to explain the viscoelastic behavior of soft materials. Scalar constants are primarily used to quantify viscoelastic elements such as springs and dashpots. However, in three-dimensional (3D) space, not all materials show the same elastic or viscoelastic properties in all directions, especially under elastic/viscoelastic wave propagation (or anisotropy). Though previously reported studies on viscoelastic models have explained a power-law decay of the memory functions, none of them explicitly explained the 3D complex modulus through a matrix notation. In this paper, we present a mathematical formulation that employs tensor algebra and fractional calculus to derive the 3D complex modulus of Kelvin–Voigt, Maxwell, and other arrangements of viscoelastic models. The 3D complex modulus provides information about the elastic wave propagation in a media and can be used to explain anisotropy in different viscoelastic materials. Additionally, an advanced formulation of the moduli can improve the modeling in finite element analysis of 3D viscoelastic materials where discretization is vital for studying media of asymmetric shapes. Finally, we demonstrated a polar decomposition method to visualize viscoelastic tensors using the Green–Christoffel tensor and surface plots to represent the degrees of anisotropy and viscoelasticity in the Fourier domain when the medium is probed by a time-harmonic homogeneous plane wave