1. Field of the Invention
The present inventions relate to apparatus and methods for ethanol production, and, more particularly, to the apparatus and methods for the production of ethanol with improved efficiencies.
2. Background of the Related Art
The ethanol production facility may use grain as the feed stock to produce ethanol by fermentation of sugar derived from the starch in the grain. Starch is a polysaccharide in which glucose molecules are primarily linked together with alpha(1-4) glycosidic bonds. The ethanol production facility typically includes one or more units configured to solubilize the starch contained within the grain, and to convert the starch into constituent sugars usually using enzymes. The ethanol production facility may include a fermenter configured to ferment the sugar using yeast to produce ethanol, which may include ethanol, butanol and various other alcohols, as well as other chemicals obtainable from the fermentation of sugar. Yeast includes yeast as well as other microorganisms capable of fermenting sugar into ethanol and/or other chemicals. A distillation unit is typically used to capture the ethanol produced by fermentation.
Microcrystalline structures are typically present in the starch that can be resistant to conversion into sugar. For example, these microcrystalline structures typically are resistant to mechanical disruption such as milling and to water penetration, and enzymes do not effectively access the starch contained in the microcrystalline structures to convert the starch into sugar. Yeast metabolize sugar to produce ethanol in the fermenter, and yeast generally cannot metabolize starch including starch bound up in microcrystalline structures. Thus, starch bound up in microcrystalline structures is not converted into sugar and, hence, into ethanol, and may be essentially lost to the ethanol production facility, resulting in inefficiencies in the ethanol production facility.
Alternatively, the ethanol production facility may use cellulosic biomass as feedstock. The ethanol production facility may include one or more units configured to convert the cellulosic material in the cellulosic biomass into sugar using enzymes, and a fermenter configured to ferment the sugar to produce ethanol. The cellulosic material includes cellulose and hemicellulose. Cellulose is a long chain of glucose molecules primarily linked together with beta(1-4) glycosidic bonds and usually embedded in an amorphous matrix of hemicellulose and lignin in the cell walls of the cellulosic biomass. Depending upon the cellulosic biomass, hemicellulose is of varying composition containing branched polymers of, for example, xylose, arabinose, galactose, mannose, and glucose. Hemicellulose is often cross-linked with lignin to create a complex web of bonds which provide structural strength but also challenge degradation. Lignin is a complex polymer of non-sugar organic molecules, which can be cross-linked to each other with a variety of chemical bonds, and is highly resistant to degradation. Lignin restricts the conversion of cellulose and/or hemicellulose into sugar by enzymes. The effect of lignin on the availability of the cellulose and/or hemicellulose cell wall components is thought to be largely a physical restriction, with lignin molecules reducing the surface area available to enzymatic penetration and activity. Thus, cellulosic material that remains bound up with lignin is not converted into sugar by the enzymes, and is lost to the ethanol production facility, resulting in inefficiencies in the ethanol production facility.
Bacteria may also cause inefficiencies in the ethanol production facility. In particular, bacteria can interfere with the conversion of sugar into ethanol by yeast in the fermenter. Typically, the bacteria level in the ethanol production facility is controlled by antibiotics, especially during fermentation. The addition of antibiotics to control the bacterial level could lead to antibiotic resistant strains of bacteria, and may, in the near future, be banned from use. The stillage and various products produced from stillage as well as other byproducts of the ethanol production facility are often used for animal feed and could contain antibiotics. The elimination or reduction of antibiotics in stillage and other byproducts of the ethanol production facility would be of value to animal feed producers.
Thus, there is a need for improved apparatus and methods for the production of ethanol that may reduce the usage of antibiotics and may also have increased efficiency.
Apparatus and methods in accordance with the present inventions may resolve many of the needs and shortcomings discussed above and may provide additional improvements and advantages that may be recognized by those of ordinary skill in the art upon study of the present disclosure.
The ethanol production facility apparatus includes a plurality of process units for converting feedstock into ethanol. The process units are in fluid communication to enable a liquid based processing stream to flow among the process units. The ethanol production facility apparatus includes a shock wave generator configured to introduce a shock wave into the liquid based processing stream.
Methods include producing a liquid based processing stream from the feedstock and introducing a shock wave into the liquid based processing stream to condition the liquid based processing stream for ethanol production. The methods may also include processing the liquid based processing stream in a plurality of process units to obtain the ethanol.
Other features and advantages of the invention will become apparent from the following detailed description and from the claims.
All Figures are illustrated for ease of explanation of basic teachings. The extensions of the Figures with respect to number, position, relationship and dimensions of the parts to form the preferred implementation will be explained or will be within the ordinary skill of the art after the following description has been read and understood. Further, the dimensions and dimensional proportions to conform to specific force, weight, strength, and similar requirements for various applications will likewise be within the ordinary skill of the art after the following description has been read and understood.
Where used in various Figures of the illustrations, the same numerals designate the same or similar parts. Furthermore, when the terms “upper,” “lower,” “right,” “left,” “forward,” “rear,” “first,” “second,” “inside,” “outside,” “front,” “back,” and similar terms are used, the terms should be understood to reference the structure shown in the illustrations and utilized to facilitate describing the illustrations.
The ethanol production facility apparatus includes a plurality of process units configured to produce ethanol from a feedstock. In various aspects, the feedstock may be grain including corn, wheat, and barley or cellulosic biomass or combinations of grain and cellulosic biomass, and the ethanol production facility apparatus may be particularly configured to produce ethanol from a grain feedstock, from a cellulosic biomass feedstock, or from combinations thereof. At least one of the process units is configured to accept the feedstock and to generate a liquid based processing stream The process units are in fluid communication to flow the liquid based processing stream amongst the process units to process the liquid based processing stream into ethanol. The ethanol production facility apparatus includes one or more shock wave generators to apply a shock wave (SW) to the liquid based processing stream at a shock wave location generally within the one or more of the process units to breakdown materials in the liquid based processing stream and/or kill bacteria to control the bacteria level in the liquid based processing stream. One or more shock wave generators may apply a shock wave to the liquid based processing stream as the liquid based processing stream flows between process units to breakdown materials in the liquid based processing stream and/or kill bacteria to control the bacteria level in the liquid based processing stream. In various aspects, the shock wave generator may include a pulsed electric field generator such as a Marx generator, a Marx-PFN generator, as well as other pulsers.
In some aspects, the ethanol production facility apparatus includes the shock wave generator to provide a shock wave configured to cause generally the dissolution of starch microcrystalline structures in order to allow the conversion of the starch in the microcrystalline structures into sugar. In some aspects, the ethanol production facility apparatus may include the shock wave generator configured to cause the disruption of starch from other portions of the grain including fiber, protein, and lipids.
In other aspects, the ethanol production facility apparatus includes the shock wave generator to provide a shock wave configured to enhance the separation of cellulosic material from lignin including other cellular materials in order to allow the conversion of the cellulosic material into sugar.
Sugar includes the saccharides that may be derived from starch as well as the saccharides that may be derived from cellulosic material such as glucose, xylose, mannose, galactose, rhamnose, arabinose, D-pentose sugars, L-sugars, and other saccharides, and combinations thereof, as would be recognized by those of ordinary skill in the art upon study of this disclosure.
In still other aspects, the ethanol production facility apparatus includes the shock wave generator to provide a shock wave configured to kill bacteria in order to control bacteria levels in the ethanol production facility apparatus.
Methods described herein include, in some aspects, providing an ethanol production facility apparatus using grain as feedstock and having a liquid based processing stream, the ethanol production facility apparatus including a shock wave generator, and applying a shock wave to the liquid based processing stream at power and frequency effective to cause generally the dissolution of starch microcrystalline structures using the shock wave generator. In some aspects, the methods may include providing an ethanol production facility apparatus using grain as feedstock and having a liquid based processing stream, the ethanol production facility apparatus including a shock wave generator, and generating shock waves in the liquid based processing stream at pressure and frequency effective to denature starch molecules using the shock wave generator. In some aspects, the methods may include providing an ethanol production facility apparatus using grain as feedstock and having a liquid based processing stream, the ethanol production facility apparatus including a shock wave generator, and generating shock waves in the liquid based processing stream at pressure and frequency effective to cleave starch molecules using the shock wave generator. In some aspects, the methods include providing an ethanol production facility apparatus using grain as feedstock and having a liquid based processing stream, the ethanol production facility apparatus including a shock wave generator, and applying a shock wave to the liquid based processing stream at power and frequency effective to cause the disruption of starch from other portions of the grain including fiber, protein, and lipids using the shock wave generator.
In other aspects, the methods include providing an ethanol production facility apparatus using cellulosic biomass as feedstock and having a liquid based processing stream, the ethanol production facility apparatus including a shock wave generator, and applying a shock wave to the liquid based processing stream at power and frequency effective to cause the disruption of the cellulosic material structures from lignin using the shock wave generator. In some aspects, the shock wave may be effective to break intermolecular and/or intramolecular bonds within and/or between the cellulose, hemicellulose, and/or lignin.
In various aspects, the methods include providing an ethanol production facility apparatus having a liquid based processing stream, the ethanol production facility apparatus including a shock wave generator, and applying a shock wave to the liquid based processing stream at a power and frequency effective to kill bacteria in order to control the bacteria level using the shock wave generator.
The Detailed Description and the Figures illustrate exemplary ethanol production facility apparatus and methods. These illustrated apparati and methods are not meant to limit the scope of coverage but, instead, to assist in understanding the context of the language used in this specification and in the appended claims. Accordingly, the appended claims may encompass variations that differ from the illustrations.
The ethanol production facility apparatus includes the shock wave generator to generate shock waves. The shock wave generator, in some aspects, may be configured as an electro-hydraulic generator where electrodes are submerged in a water-filled housing. The electro-hydraulic generator initiates the shock wave by an electrical discharge between the electrodes. Vaporization of water molecules between the electrodes produces vapor bubbles that grow and rupture resulting in an explosion thus generating the shock wave. The electro-hydraulic generator generates a shock wave with a fast rise time and generates focused energy over a broad area to deliver a large amount of energy. In addition, the shock waves can be further focused through the use of focusing reflectors in an electro-hydraulic generator.
The shock wave generator, in some aspects, may be configured as an electromagnetic generator where opposing metal membranes are connected to electromagnetic coils. When a high current passes through one coil, a strong magnetic field is generated that induces a high current in the opposing membrane and accelerates the metal membrane away from the coil to generate a pressure wave.
In some aspects, the shock wave generator may be configured as a piezoelectric generator form shock waves by the application of high voltage pulses to the piezoelectric crystals, which convert electrical signals into mechanical vibrations. The crystals contract and expand, generating the shock wave. Pulsed electric discharges in a solid dielectric immersed in liquid such as water can create shock waves on the order of 1,000-10,000 MPa.
Organic polymers such as proteins and polysaccharides can be denatured through the application of shock waves with pressures ranging from about 300-600 MPa generally at ambient temperature or with reduced heat input. The application of hydrostatic pressure to starch can cause the gelatinization of starch. At temperatures greater than about 40° C. and pressures greater than about 500 MPa, the susceptibility of starches to amylase digestion is greatly increased.
There are three types of molecular bonds that exist in the starch matrix: covalent, hydrogen, and van der Waals. Of these three, the dissociation energy of the covalent bonds is one to two orders of magnitude higher than the other two. At pressures between 1000-10000 MPa, the covalent bonds can be dissociated and the starch matrix broken down into both amylose and amylopectin functional groups. Accordingly, the shock wave generator 120 may generate shock waves with transient pressures of more than about 1000 MPa, so that the conversion of starch to sugar by enzymes such as alpha-amylase and gluco-amalyse may be achieved generally at ambient temperatures with little or no heat required. The addition of heat to raise the temperature of the liquid based processing stream to about 40° C. may reduce the conversion time and increase the enzyme efficiency.
One or more shock wave generators may be disposed about the ethanol production facility apparatus to generate shock waves configured to cause generally the dissolution of starch microcrystalline structures in order to allow the conversion of the starch in the microcrystalline structures into sugar.
Shock waves can kill bacteria. Most bacteria are killed by shock waves with pressures between about 300-600 MPa at room temperature. Accordingly, the shock wave generator may generate high pressure shock waves to eliminate or reduce the number of bacteria in the liquid based processing stream, which may increase the effectiveness of the yeast during fermentation.
One or more shock wave generators may be variously disposed about the ethanol production facility apparatus to apply shock waves at locations effective to control the bacteria level in the liquid based processing stream. In some aspects, one or more shock wave generators may be disposed about the ethanol production facility apparatus and configured to generate shock waves in the liquid based processing stream at a location effective to control the bacteria level in the fermenter.
As shown in
The mill 510, the cooker 520, the fermenter 550, and the distillation unit 560 are in fluid communication so that the liquid based processing stream may flow from the mill 510 to the cooker 520, from the cooker 520 to the fermenter 550, and from the fermenter 550 to the distillation unit 560. The liquid based processing stream is communicated by pipe 752 including channels, ducts, troughs, and other conveyance structures in various implementations. The nature of the liquid based processing stream generally changes from slurry to mash to fermented mash, and, finally, to ethanol and stillage as the liquid based processing stream is communicated through various process units of the ethanol production facility apparatus 10. Various pumps, pipes, valves, vessels, ducts, storage reservoirs, heat exchangers, boilers, process control systems, electrical power systems, and other such apparatus may be provided as part of the ethanol production facility apparatus 10 inter alia to communicate the liquid based processing stream between the mill 510, the cooker 520, the fermenter 550, and the distillation unit 560, and/or as components of the mill 510, the cooker 520, the fermenter 550, the distillation unit 560, and/or other process units. The process units including the mill 510, the cooker 520, the fermenter 550, and the distillation unit 560 are generally configured to separate the starch in the liquid based processing stream from other portions of the grain feedstock, to convert the starch in the liquid based processing stream to sugar, and to ferment the sugar in the liquid based processing stream to produce ethanol.
Starch may be bound up with other portions of the grain in grain fragments, and starch may be bound up in starch microcrystalline structures in the liquid based processing stream. One or more shock wave generators may be disposed about the ethanol production facility apparatus 10 to provide a shock wave configured to cause generally the dissolution of starch microcrystalline structures in order to allow the conversion of the starch into sugar. In various aspects, one or more shock wave generators may be disposed about the ethanol production facility apparatus 10 to provide a shock wave configured to loosen the structure of the grain fragments to enhance solubilization of the starch in the grain fragments. The shock wave generator may generate a shock wave configured to separate the starch from other portions of the grain including fiber, lipid, and protein. Shock waves are effective in killing bacteria in food processing. One or more shock wave generators may be variously disposed about the ethanol production facility apparatus 10 to apply shock waves at locations effective to control the bacteria level in the liquid based processing stream.
The ethanol production facility apparatus 10 may be configured in other ways to use grain as feedstock to produce ethanol. One or more shock wave generators may be disposed about said ethanol production facility apparatus 10 in various ways to cause the dissolution of starch microcrystalline structures, to loosen the structure of grain fragments, and/or to control bacteria levels, as would be recognized by those of ordinary skill in the art upon study of this disclosure.
As illustrated in
The mill unit 810, the separation unit 815, the liquefaction unit 830, the saccharification unit 840, the fermenter 850, and the distillation unit 860 are in fluid communication by pipe 752, so that the liquid based processing stream may be communicated from the mill unit 810 to the separation unit 815, from the separation unit 815 to the liquefaction unit 830, from the liquefaction unit 830 to the saccharification unit 840, from the saccharification unit 840 to the fermenter 850, and from the fermenter 850 to the distillation unit 860 in this implementation. Various pumps, pipes, valves, vessels, storage reservoirs, heat exchangers, boilers, process control systems, and other such apparatus may be provided as part of the ethanol production facility apparatus 11, inter alia, to communicate the liquid based processing stream between the mill unit 810, the separation unit 815 the liquefaction unit 830, the saccharification unit 840, the fermenter 850, and the distillation unit 860.
As illustrated in
The cellulosic material may be bound up with other portions of the cellulosic biomass such as lignin. For example, the cellulosic biomass fragments may be composed of one or more plant cells and/or portions of plant cells. The shock waves may cause damage to plant cell walls as well as membranes of internal organelles within the plant cells, leading to easier passage of material into and out of the cellulosic biomass fragments, which may enhance the separation of cellulosic material from lignin contained in the cellulosic biomass fragments. Accordingly, one or more shock wave generators may be disposed within the ethanol production facility apparatus 11 to provide a shock wave configured to cause generally damage to cellulosic biomass fragments in order to enhance the separation of cellulosic material from lignin in the cellulosic biomass fragments.
The use of acids and/or bases to separate cellulosic material from lignin or hydrolize the cellulosic material into sugar may form undesirable byproducts such as acetic acid, formic acid, levulinic acid, phenol, vanillin, furfural and hydroxymethyl furfural (HMF). Such byproducts formed during the hydrolysis pretreatment step are known to be toxic to yeast or to inhibit yeast metabolism thereby reducing the fermentation efficiency of yeast. Furthermore, compounds such as furfural and HMF result from the breakdown of pentoses (e.g., xyloxe) and hexoses (e.g., glucose) thereby reducing the amount of fermentable sugars available for ethanol production. The application of shock waves to the liquid based processing stream by one or more shock wave generators may reduce or eliminate the use of acids and/or bases, and, hence, reduce or eliminate the byproducts. The elimination of the byproducts may increase the efficiency of ethanol production.
For example, in various aspects, one or more shock wave generators may be disposed about the ethanol production facility apparatus 11 to provide the shock wave to the liquid based processing stream in order to enhance the separation of cellulosic material from lignin. In various aspects, one or more shock wave generators may be disposed about the ethanol production facility apparatus 11 to provide shock wave to the liquid based processing stream configured to hydrolyze the cellulosic material into sugar. In various aspects, one or more shock wave generators may be disposed about the ethanol production facility apparatus 11 to provide shock wave to the liquid based processing stream to kill bacteria in order to control the bacteria level in the liquid based processing stream.
The ethanol production facility apparatus 11 may be configured in other ways to use cellulosic biomass as feedstock to produce ethanol. One or more shock wave generators may be disposed about said ethanol production facility apparatus 11 in various ways to control bacteria levels and/or to enhance the separation of cellulosic material from lignin, as would be recognized by a person of ordinary skill in the art upon study of this disclosure.
In
The ethanol production facility apparatus 10 (
As illustrated in
The cooker 520 includes one or more vessels configured to heat the liquid based processing stream communicated from the mill 510 along with enzymes such as alpha-amylase in order to solubilize and liquefy the starch in the grain fragments in liquid based processing stream. This may be referred to as gelatinization and liquefaction, respectively. The cooker 520 may be configured to implement various cooking processes such as jet cooking, which may occur at temperatures in excess of 100° C. and at pressures of several atmospheres. The heat and/or pressure in the cooker 520 may cause water molecules to be adsorbed or absorbed by the starch, which may cause the starch molecules to expand, weaken the structure of the starch, and solublilize the starch molecules. The enzymes such as alpha-amylase generally cleave the long polysaccharide chains of the starch molecules into sugar chains such as maltodextrins and oligosaccharides to liquefy the starch, and may also weaken the structure of the starch to solubilize the starch molecules.
Shock wave generators may be disposed about the ethanol production facility apparatus 10, as illustrated in
As illustrated in
One or more shock wave generators 516 may apply a shock wave to the liquid based processing stream generally within the cooker 520 to cause generally dissolution of starch microcrystalline structures in order to produce a more complete solubilization of starch, as illustrated in
The liquid based processing stream is communicated from the cooker 520 to the fermenter 550 through pipe 752 in the illustration of
One or more shock wave generators 534 may apply the shock wave to the liquid based processing stream within the pipe 752 at a shock wave location between cooker 520 and fermenter 550 in the implementation illustrated in
The liquid based processing stream is communicated from the fermenter 550 to the distillation unit 560 in
Shock wave generators may be employed in various ways in the mill 510 to apply shock waves to the liquid based processing stream to generally separate the starch from other portions of the grain in order to increase the availability of starch for conversion into sugar. For example, the mill 510 may be implemented as a wet mill 600 (
One or more shock wave generators 625 may apply shock waves to the liquid based processing stream within the pipe 752 at a shock wave location between first grinding unit 620 and germ separation unit 630. The applied shock waves result in enhanced separation of germ in germ separation unit 630, and in enhanced separation of fiber from starch and gluten in the fiber separation unit 650 to increase the availability of the starch for conversion into sugar.
One or more shock wave generators 645 may apply shock waves to the liquid based processing stream within the pipe 752 at a shock wave location between second grinding unit 640 and fiber separation unit 650, as illustrated in
The ethanol production facility apparatus 11 (
The liquid based processing stream is communicated from saccharification unit 840 to the fermenter 850. The fermenter 850 uses yeast to ferment the sugar in order to produce ethanol. The ethanol may be recovered from the liquid based processing stream by distillation unit 860.
As illustrated in
One or more shock wave generators 843 may apply shock waves to the liquid based processing stream within pipe 752 at a shock wave location between the saccharification unit 840 and the fermenter 850, as illustrated in
The shock wave generator 120 including the electro-hydraulic system, the electromagnetic generator, and the piezoelectric generator may include a pulsed electric field generator 700 such as a Marx Generator, a Marx-PFN generator, as well as other pulsers to drive the generation of shock waves. An illustration of the shock wave generator configured, in part, as a pulsed electric field generator 700 is illustrated in
The discharge of the capacitors 730a, 730b, 730c, 730d into the load 750 may be controlled by switches 720 illustrated as switches 720a, 720b, 720c, 720d in
The shock wave generator 120 may apply the shock wave to the liquid based processing stream in a continuous flow process. Various configurations of the load 750 are suitable. An illustrative load 770 is shown in
Methods described herein may include, in some aspects, providing a ethanol production facility apparatus 10 using grain as feedstock and having a liquid based processing stream, the ethanol production facility apparatus 10 including at least one shock wave generator. The methods may include applying a shock wave to the liquid based processing stream at power and frequency effective to cause the disruption of starch from other portions of the grain including fiber, protein, and lipids using the at least one shock wave generator, and may include applying a shock wave to the liquid based processing stream at power and frequency effective to cause generally the dissolution of starch microcrystalline structures. In various aspects, the methods may include generating shock waves in the liquid based processing stream at pressure and frequency effective to denature starch molecules using the shock wave generator. In various aspects, the methods may include generating shock waves in the liquid based processing stream at pressure and frequency effective to cleave starch molecules using the shock wave generator.
The methods may include including a mill 510, cooker 520, a fermenter 550 in the ethanol production facility apparatus 10 and applying the shock wave to the liquid based processing stream between the mill 510 and the cooker 520, applying the shock wave to the liquid based processing stream in conjunction with the cooker 520, applying the shock wave to the liquid based processing stream between the cooker 520 and the fermenter 550 to dissolve generally starch microcrystalline structures using one or more shock wave generators, in various aspects. In various aspects, the methods may include configuring the ethanol production facility apparatus 10 with a wet mill 600 and applying shock waves at one or more locations in the wet milling 600 configured to cause generally separation of starch from other portions of the grain and/or dissolution of starch microcrystalline structures using one or more shock wave generators.
The methods may, in some aspects, include providing an ethanol production facility apparatus 11 using cellulosic biomass as feedstock and having a liquid based processing stream, the ethanol production facility apparatus 11 including at least one shock wave generator. The methods may include applying a shock wave to the liquid based processing stream at power and frequency effective to cause the disruption of the cellulose and hemicellulose structures from lignin using the at least one shock wave generator. The methods may include including a milling unit 810, separation unit 815, and fermenter 850 in the ethanol production facility apparatus 11 and applying the shock wave to the liquid based processing stream between the milling unit 810 and the separation unit 815, applying the shock wave to the liquid based processing stream in conjunction with the separation unit 815, and applying the shock wave to the liquid based processing stream between the separation unit 815 and the fermenter 850 to cause the disruption of the cellulosic material structures from lignin using one or more shock wave generators, in various aspects.
In various aspects, the methods may include providing an ethanol production facility apparatus 1 having a liquid based processing stream, the ethanol production facility apparatus including at least one shock wave generator, and applying a shock wave to the liquid based processing stream at power and frequency effective to kill bacteria in order to control the bacteria level using the at least one shock wave generator. The methods may include applying the shock wave to the liquid based processing stream at a location effective to control the bacteria level in the fermenter 550 in the ethanol production facility apparatus 10 using grain as feedstock. The methods may include applying the shock wave to the liquid based processing stream at a location effective to control the bacteria level in the fermenter 850 in the ethanol production facility apparatus 11 using cellulosic biomass as feedstock.
The foregoing discussion discloses and describes merely exemplary implementations. Upon study of the specification, one of ordinary skill in the art will readily recognize from such discussion, and from the accompanying figures and claims, that various changes, modifications and variations can be made therein without departing from the spirit and scope of the invention as defined in the following claims.
The present application claims the benefit and priority of U.S. provisional patent application 60/934,782 filed on Jun. 15, 2007, the disclosure of which is hereby incorporated by reference in its entirety.
Number | Date | Country | |
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60934782 | Jun 2007 | US |