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This versatile and highly efficient refractometer determines the concentration of a fluid by measuring in real time the index of refraction of a fluid. A look-up...
This versatile and highly efficient refractometer determines the concentration of a fluid by measuring in real time the index of refraction of a fluid. A look-up table can be used to relate the index of refraction to the concentrations of the fluid mixture. Small changes in the concentrations of the fluid can be detected by measuring small changes in the index of refraction. The refractometer can be used as an inline process or hand-held device. The entire system, including the sensor housing, inexpensive charge-coupled device (CCD) camera, and digital image processing software, costs less than $1,000. It is fully immersible and provides an accuracy of 0.1% of scale. Refractive index sensing heads using this technology can be constructed for less than $1 and may be used for remote or in situ refractive index sensing operations (process monitoring in a tank, in a well, in soils, etc.)
A refractometer is a measuring device designed to determine the index of refraction. The refractometer market is very competitive. A wide variety of types and prices for refractometers are available, including hand-held, laboratory, inline process, and automotive at a cost ranging from a few hundred dollars to $12,000. Refractometers are used in the food, beverage, chemical, petrochemical, automotive, and pulp and paper industries. Most inline process refractometers cost $8,000 to $12,000. These refractometers are fully computerized, use expensive CCD arrays, have automatic wash control, and sometimes have redundant sensing heads.
Researchers at the University of Illinois at Urbana-Champaign have invented a lower cost refractometer ideally suited for applications where more expensive refractometers would not be justified (e.g., airplane de-icing, measuring water-soluble oils in machine tool coolant, high-end ink jet printing, controlling the concentration of methanol in fuel cells).
How It Works
This invention works by measuring the amount of bending that occurs when light enters a fluid. The refractometer is an integrated sensor housing containing an LED, a flat (not prism) optical element made of glass or sapphire, and a photodetector. Diffused light from the LED passes through the optical element, the other side of which is in contact with the fluid. A portion of the light is refracted reflected back to the photodetector. This results in a sharp ring of light being formed at a specific distance from the light source that is related to the fluid's refractive index. An inexpensive CCD camera and digital image processing software identifies changes in the light to dark regions of the light ring. By measuring the diameter of the ring, one can determine the index of refraction of the fluid. Indices of refraction from 1.3 to 1.6 can be measured. A look-up table then can be used to relate the index of refraction to the concentrations of the fluid mixture. Small changes in the concentrations of the fluid can be detected by measuring small changes in the index of refraction.
Why It Is Better
Other refractometers that use CCD cameras and have microprocessors for processing the image cost approximately $10,000. This refractometer can be used as an inline process or hand-held device, and the entire system including the sensor housing, inexpensive CCD camera, and digital image processing software costs less than $1,000. The LED (infrared, red, or yellow LEDs may be used), optical element, and photodetector can be molded into a single small sensing package. This sensing package then can be interfaced with other companies' hand-held devices and data acquisition systems. Another advantage of the invention is that it uses a simple flat optical element. For fluids with an index of refraction below 1.5, a flat piece of glass can be used. For fluids with a higher index of refraction, such as refrigerant containing oil, a sapphire optical element can be used. The sapphire optical element is 0.5"-diameter, 1.5-mm- thick, and is capable of measuring the full range of concentration from pure oil to pure refrigerant. Refractometers often are used in the food and beverage processing industries, where small changes in the Brix concentration are critical, and in the pulp and paper industry. This refractometer can measure lubricating oil in refrigerant lines and dissolved solids in cutting fluids with an accuracy of 0.1% of scale. Because it uses an integrated sensor housing, this refractometer is particularly appropriate for applications where the refractometer needs to be immersed into a liquid or placed within a permeable solid.
This set of technologies takes up the problems associated with ceramics in oxidizing environments. By strengthening materials and slowing the growth of cracks it...
This set of technologies takes up the problems associated with ceramics in oxidizing environments. By strengthening materials and slowing the growth of cracks it is possible to produce flaw tolerant oxide ceramic composites.
The University of Illinois has developed a suite of technologies for strong, tough, flaw-tolerant, oxide ceramic composites that achieve a more graceful failure. These technologies address the brittleness and unreliability of ceramics in oxidizing environments. The purpose of these technologies is to slow crack growth in ceramic composites, as a means of toughening the materials. Rather than propagating straight through the material at high speed, the crack takes a zigzag path, doing work while it propagates, ultimately wearing itself out and making the resulting material flaw tolerant.
This technology offers an improved approach to repairing damaged articular cartilage using traditional bonding adhesives or surgical glues. The technique removes...
This technology offers an improved approach to repairing damaged articular cartilage using traditional bonding adhesives or surgical glues. The technique removes synovial fluid, which inhibits the bonding of surgical glues, from the cartilage surface. A poly(hydroxy substituted amino acid) composite is mixed with the synovial fluid, forming a liquid crystalline matrix on the cartilage surface. This matrix can be easily removed, taking the synovial fluid with it and leaving behind a clean surface so that surgical glue can bond properly. By allowing surgical glues to bond properly to cartilage surfaces, this technology greatly improves the techniques used to repair articular cartilage damaged due to trauma or congenital abnormalities. Effective cartilage repair can relieve joint pain, restore joint function, and postpone or even eliminate the development of osteoarthritis.
This technology is a new method for enhancing the performance of surgical glue/adhesive during repair of articular cartilage.
Found in joints throughout the human body, articular cartilage is essential for proper joint function. Once damaged (through trauma or congenital abnormalities), articular cartilage has a limited capacity to repair itself. Proper repair usually requires reconstructive orthopedic surgery. Surgical methods can include transplantation or allografts, implantation of artificial prosthetic devices, and neocartilage formation utilizing isolated chondrocytes in an organic support matrix or scaffold.
However, these surgical methods have a key limitation: the adhesive or glue used in bonding and stabilizing the transplant, implant, or scaffold on the cartilage surface is negatively affected by the synovial fluid that provides lubrication and nutrition to joint tissues.
This technology creates a liquid crystalline matrix that can be easily removed, taking the synovial fluid with it and leaving behind a clean (i.e., fluid free) cartilage surface. Thus, the efficacy of the surgical adhesives/glues is enhanced rather than inhibited.
A solid or aqueous composition of poly(hydroxy substituted amino acid) is mixed with synovial fluid in the joint. This mixture forms a liquid crystalline (or mesomorphic) matrix on the surface of the cartilage.
For example, when aqueous polythreonine comes in contact with the synovial fluid in the joint, a gelatinous matrix forms that is birefringent (i.e., a liquid crystalline matrix). Other suitable polymers include polyserine, polytyrosine, poly(hydroxyproline), and poly-5-hydroxy lysine. Polymers of L-amino acids are preferred.
The polymer-synovial matrix can be easily removed from the cartilage surface, taking the synovial fluid with it and leaving behind a clean cartilage surface so that the surgical glue/adhesive can bond properly.
Although developed specifically for cartilage surfaces, it is expected that the technology also could be used to modify the surfaces of other joint-associated tissues, including bones, ligaments, and tendons.
This technology simplifies manufacturing processes for plastics while also improving melt flow characteristics of polymers. It is a method for inexpensive...
This technology simplifies manufacturing processes for plastics while also improving melt flow characteristics of polymers. It is a method for inexpensive synthesis of monomers for production of hyperbranched polymers (HBP). These polymers maintain desirable properties of linear polymers, such as thermal and chemical stability, while also maintaining high solubility and low viscosity.
This technology offers the plastics additives industry a way to produce an optimal melt flow product while simplifying and reducing costs of the manufacturing process. It can be used to produce coatings, additives, or stand-alone polymers as well as other materials. It is thermally stable and can conform to any architecture needed.
The technology includes methods for producing AmBn monomers and for producing high molecular weight (MW) star, linear, hyperbranched, and dendritic polyethermides (PEIs) from those monomers and their various combinations. Careful control of the chemistry of the monomers can selectively target production of processible, highly branched (hyperbranched) polymers that are mechanically, thermally, and hydrolytically stable as well as resistant to oxidative degradation.
The process typically takes an aromatic monomer containing silylated phenols and fluorphthalimed reactive groups (ABn) types monomer and reacts it with a catalytic amount of cesium fluoride in high boiling, polar, aprotic solvents to produce a high-MW polymer This technique produces polymers that are highly amorphous and easily isolated from crystalline monomers that are easily synthesized and purified in three steps from inexpensive commercial starting materials.
Further modifications produce a polymer with physical properties that are dominated by the endgroup functionalities and not by the repeat unit. The process controls the degree of branching and the polymer's structure, thereby targeting and controlling physical properties that lie between those of a linear and a "perfect" dendritic structure.
The degree of branching (DB) of a polymer is defined on a scale from 0 to 1, with linear polymers approaching 0 and dendritic (maximally branched) polymers approaching 1. Those in between are termed branched or hyperbranched. This technology can produce polymers exhibiting the entire range of branching.
Physical properties of dendritic macromolecules, such as crystallinity, viscosity and solubility, are determined by their unique globular shape and the endgroups that occupy their periphery. Techniques for producing high MW, "perfect" dendrimers require many synthetic steps that increase the cost and limit the scale of production. This method has few synthetic steps and provides macromolecules with properties very similar to dendrimers with a fraction of the time and cost.
The physical properties of linear polymers are determined by intermolecular interactions and the structure of the repeat itself. Linear polymers increase in viscosity and decrease in solubility as their MW increases. For uses such as coatings or films, this quality makes the processing difficult. This technology can create highly branched, high-MW polymers with characteristics of linear polymers but much lower viscosities and much higher solubilities. This makes it ideal for use as an additive to commercially available polymers for reducing the melt and/or solution viscosity without compromising the physical properties of the parts or composites (e.g., injection molded) being created. Since the materials are high molecular weight, they are ideal candidates as viscosity reducers for coatings to reduce VOC content.
The synthesis of hyperbranched monomers, historically costly and difficult, yields only small quantities of material. Techniques for improving the scaleability of hyperbranched monomers have not produced polymers that can withstand severe chemical, mechanical, thermal, or oxidative conditions. This new technology produces hyperbranched polymers that are amorphous solids with excellent chemical stability: they can withstand temperatures above 500 C in air and nitrogen, their chemical solubility profile can be easily modified, and they can be produced in bulk quantities while still maintaining their preferred characteristics.
Lastly, the technology can effectively eliminate separation of polymer phases within blended products. It can camouflage hyperbranched polymers by selecting endgroups or linear polymer chains that make the particle compatible or homogenous within the matrix.
This technology is a microcombustor a compact, submillimeter device that burns hydrocarbon fuels homogeneously as a source of power. It efficiently converts heat...
This technology is a microcombustor a compact, submillimeter device that burns hydrocarbon fuels homogeneously as a source of power. It efficiently converts heat generated by combustion into electric power, and has the potential to replace batteries in portable applications requiring long-term power. This device is actually the burner, and will eventually form the core of a system that includes peripheral technologies, such as thermal isolation.
This microcombuster is designed to burn hydrocarbon fuels homogeneously and to convert generated heat into electric power, on a compact, submillimeter scale. While this technology provides the burner, it will ultimately be developed as the central element in a suite of peripheral technologies, such as thermal isolation, enabling it to be functional on a practical scale (i.e., be worn by military personnel).
This technology burns hydrocarbons in homogeneous combustion. It has attained temperatures over 1,000 C. The higher the temperature, the more efficient the conversion to electric power will be (the higher the practical power density). The development of the microcombustor addresses two essential technological problems: the need for a wall material that retards/prevents radical formation; and, a wall material that can withstand very high temperatures. Various materials are being tested for the microcombustor and the underlying physics of the device are being determined. The wall material of this device required a chemistry that does not force recombination of radicals at the wall, as by catalysis (a process that would quench the flame).
This technology uses a combination of silica, alumina, and magnesium to create a wall that disallows recombination and also rejects the radicals, returning them to the gas phase to continue to react. These materials also can tolerate high temperatures, an important factor in solving the second problem. The walls of the microcombustor must be able to tolerate very high temperatures-more than 1,000 C-to preserve efficiency.
As an alternative to thick walls, which would make the device rather large, a thermal isolation technology is under development that will enable thin walls to be hot on the inside while their outsides remain cool. This will allow the microcombustor to be worn in close proximity to a user.
The microcombustor gives a very high practical power density. Batteries that produce high energy density are often too heavy and, typically, have low power density (and vice versa). They cannot provide the energy density required for many high-power applications, for light weight, for any extended period. Compared to the highest possible energy density battery, which may someday provide 2,000 kwh/kg, homogeneous combustion yields up to 18,000 kwh/kg, a nine-fold enhancement.
The microcombustor, due to its very small size and weight, can deliver extremely high power density for extended periods of time, which cannot be matched by batteries of any type. If used as a heat source for microchemical reactors, the system would involve sandwiching the microcombustor between microreactors and then insulating the package. This type of microreactor can then be used to generate a wide range of chemicals, on the spot, for various applications in industry.
This is particularly true for chemicals that are difficult to make and store, or are expensive, unstable, or toxic, thus requiring only very small quantities. For power generation, the reactor can be used to generate hydrogen gas for fuel cells, on demand, without requiring hydrogen to be stored, thereby increasing safety. By itself, if the microcombustor was used in a thermophotovoltaic system, it would be the alternative to solar cells and thermoelectricity, which are inefficient and not popular.
The microcombuster is designed for applications where a lot of power is needed quickly, in a small package.
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The University's Vapor Phase Removal and Recovery System (VaPRRS) is a patented long-lasting filter that effectively removes dilute volatile organic compounds (...
The University's Vapor Phase Removal and Recovery System (VaPRRS) is a patented long-lasting filter that effectively removes dilute volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) from gas streams and recovers them as pure liquids. The technology can be integrated into a variety of manufacturing facilities and air pollution control (APC) systems to make them more effective. VaPRRS is a VOC/HAP recovery system that uses an activated carbon fiber cloth and electrothermal desorption (ED) to inexpensively and selectively remove vapors from gas streams. The system rapidly adsorbs and then efficiently regenerates the sorbent and allows for condensation of the sorbate gas all within one control volume. Experimental and numerical prototyping has successfully demonstrated the removal of 4-methyl-2-pentanone (MIBK), toluene, methyl propyl ketone (MPK), methyl ethyl ketone (MEK), and hexane from laboratory generated air steams.
This technology uses activated-carbon fiber cloth (ACFC) as an alternative adsorbent to traditional granular activated carbon (GAC) to remove and recover organic vapors from gas streams. The ACFC is microporous, has up to 250% of the adsorption capacity of GAC, has faster mass and heat transfer properties than GAC, and is ash free to inhibit chemical reactions between the ACFC and the adsorbed vapors. Electrothermal desorption can be used to rapidly regenerate the ACFC with lower energy requirements than steam- or heated nitrogen-based regeneration. ED also eliminates the need for an adsorbent drying step and the recovered solvent/water separation processes usually required with conventional steam regeneration technology.
As shown in Figure 1 attached, this technology consists of two adsorption/desorption units that enclose hollow elements containing ACFC and provide gas ports at either end. The compounds are adsorbed onto ACFC cartridges (Figure 2 attached) that are electrothermally regenerated at a very rapid rate, causing the adsorbate to condense within the adsorption vessel itself and produce two-phase flow of the effluent during regeneration. The ACFC elements provide controlled electrical resistance, allowing for direct electrothermal heating and rapid regeneration of the ACFC and recovery of the VOCs/HAPs. Rapid ED with in-vessel condensation results in significant reductions in system complexity, cycle times, and nitrogen consumption. This new system also operates without the use of steam, heated inert gas, vacuum, or a refrigeration system. The pilot-scale system regenerates the ACFC within 40 minutes.
Continuous VOC/HAP capture and recovery tests were performed with the bench-scale unit (125 mm diameter) while removing an array of solvents at a total gas flow rate ranging from 5-85 sLpm. The adsorption vessel contained 128 grams of ACFC. Single-component organic vapor tests were performed with MIBK; toluene; n-hexane, 2-pentanone (MPK); MEK; and n-hexane with controlled concentrations ranging from 100 to 10,000 ppmv in air. Overall removal efficiencies of greater than 99% were measured during the experiments.
Companies can license the VaPRRS technology for integration into existing manufacturing operations and APC systems for a wide variety of applications, including:
Manufacturing: This technology can be used to recover VOCs/HAPs generated during the manufacturing of various products, including:
To license the entire Vapor Phase Removal and Recovery System portfolio, click here.
This technique for liquid composite molding uses a solid catalyst recrystallized onto preplaced fiber reinforcements to produce high-strength polymer matrix...
This technique for liquid composite molding uses a solid catalyst recrystallized onto preplaced fiber reinforcements to produce high-strength polymer matrix composites. The polymerization is initiated by the preform itself, eliminating the need to mix multiple resins and catalysts before filling the mold. Having polymerization triggered by the preform simplifies the process, saves time, and eliminates mixing equipment.
Liquid composite molding processes have been popular since the 1940s. In the last 10 to 15 years, significant improvements have been made in developing low-viscosity thermosetting resin systems necessary to obtain high fiber volume parts. Also, automatic methods like weaving, braiding, and knitting have greatly reduced the cost of producing fiber preforms.
All liquid composite molding processes require that the resin injected into the mold is a reactive liquid. Some resins such as epoxy and urethane are highly reactive and must be kept separate until just before they are injected into the mold. Other resins are activated by a catalyst in the holding tank. These multipart resin systems require complex mixing, metering, and use of injection equipment with accurate ratio control. The multipart resin systems also may require heating tanks, hoses, pipes, and pumps; motionless mixing; efficient circulation to help prevent cure or degradation of the resin in a holding tank; and easy and safe cleaning/purging.
This new liquid composite molding technique uses a one-part monomer and a solid catalyst crystallized onto the fiber reinforcement. The polymerization is initiated by the preform itself, eliminating the need to mix or add multiple resins and catalysts before filling the mold.
Since it uses a single resin, the process also eliminates the need for the mixing equipment and reduces the heating and cleaning requirements of the injection equipment.
The best material system for use with this technology is one that uses polydicyclopentadiene (pDCPD). This polymer forms very rapidly at room temperature by a ring-opening metathesis polymerization (ROMP) of its low-viscosity monomer. The first step in this process requires recrystallizing the catalyst onto the fiber preform. The reactive fiber preform is then placed into the mold, the mold is closed, and the monomer is injected into it. Once the monomer has had time to react with the catalyst on the fiber preform and polymerize, the completed part is removed from the mold.
This technique can be used in liquid composite molding, such as resin transfer molding (RTM), vacuum-assisted RTM (VARTM), and structural reaction injection molding (SRIM), for parts with end-use applications in:
Because multiple resins and catalysts do not need to be added or mixed before being pumped into the mold, this process:
This purification technology is a means of activating a ceramic substrate and preparing a chitosan gel that coats the surface of the substrate as well as its...
This purification technology is a means of activating a ceramic substrate and preparing a chitosan gel that coats the surface of the substrate as well as its interstitial spaces. When used in water purification, this biosorbent provides a more efficient and less expensive method for removing heavy metals and other contaminants from water.
This invention provides a novel composite biosorbent for treatment of aqueous waste water streams containing heavy metals. The biosorbent is prepared using chitosan and a support material. Chitosan is a biomaterial derived from deacetylation of chitin from the shells of shrimp, crab, and other arthropods. Chitosan is added onto activated alumina particles, enabling water flow through a columnar structure and providing a greater surface area of sites for attracting heavy metal ions, thereby allowing purification of large volumes of water.
Activation of the alumina (or perlite) with carboxylic acid cleans the surface, increases its reactivity, and facilitates binding of the chitosan to the ceramic. The activation of the ceramic makes it more porous and extends the surface area onto which the chitosan can bind. Spreading the chitosan gel over the largest possible surface area, including the pores, greatly increases the absorption of the gel per given amount of ceramic.
This technology can be used to remove metallic anions (negatively charged) and cations (positively charged) found in aqueous solutions, such as: trivalent chromium cation, hexavalent chromium anion, and the cationic and anionic forms of arsenic. Other metals that can be removed include: lead, copper, nickel, silver, molybdenum and mercury. Water streams containing radioactive materials such as cesium, strontium, thorium and uranium can also be treated with this biosorbent.