What is claimed is:
1. An apparatus for dividing the flow of a gas stream, comprising:
an inlet conduit for receiving said gas stream;
outlet conduits in fluid communication with said inlet conduit for delivering said gas stream;
a balancing gas conduit in fluid communication with an outlet conduit;
a balancing gas feeder in fluid communication with said balancing gas conduit; and
a balancing gas controller.
2. The apparatus of claim 1, wherein said balancing gas controller comprises a valve in fluid communication with said balancing gas conduit.
3. The apparatus of claim 1, wherein said balancing gas feeder comprises a blower.
4. The apparatus of claim 1, comprising:
balancing gas conduits, each balancing gas conduit being in fluid communication with an outlet conduit and a balancing gas feeder; and
controllers, each controller for controlling the rate of flow of balancing gas through an associated balancing gas conduit.
5. The apparatus of claim 4, wherein each balancing gas conduit is associated with a controller.
6. The apparatus of claim 4, wherein each balancing gas conduit is in fluid communication with a common balancing gas feeder via a balancing gas feed conduit.
7. The apparatus of claim 4, wherein said controllers comprise valves, and further comprising a flow sensor disposed upstream of a valve.
8. The apparatus of claim 4, further comprising a heater in thermal communication with a balancing gas conduit.
9. The apparatus of claim 8, further comprising a flow sensor disposed upstream of said heater.
10. The apparatus of claim 1, further comprising a source of sulfur trioxide in fluid communication with said inlet conduit and injection probes in fluid communication with an outlet conduit.
11. The apparatus of claim 10, wherein said balancing gas feeder comprises an air blower, and said apparatus comprises:
balancing air conduits, each balancing air conduit being in fluid communication with said blower and an associated outlet conduit;
an air feed conduit in fluid communication with said blower and said balancing air conduits;
valves for controlling the rate of flow of air through said balancing air conduits, each valve being in fluid communication with an associated balancing air conduit; and
a heater in thermal communication with one or more of said air feed conduit and said balancing air conduits for heating air.
12. An apparatus for controlling the flow division of a conditioning gas stream through conditioning gas outlet conduits, comprising:
balancing gas conduits adapted for fluid communication with conditioning gas outlet conduits;
flow sensors on one or more of said balancing gas conduits;
valves for controlling the rate of flow of balancing gas, each valve being in fluid communication with a balancing gas conduit;
a blower for feeding balancing gas;
a balancing gas feed conduit in fluid communication with said blower for conveying balancing gas to said balancing gas conduits;
a heater in thermal communication with one or more of said balancing gas conduits and said balancing gas feed conduit for heating balancing gas; and
a process control system adapted for receiving demand signals related to feed rate demands of conditioning gas from each of said conditioning gas outlet conduits, for receiving balancing gas flow sensor signals, and for providing control signals to one or more of said valves and said blower.
13. A method for controlling the flow division of a gas stream, comprising the steps of:
dividing a process gas stream into process gas stream fractions; and
injecting a balancing gas stream into a process gas stream fraction in an amount sufficient to displace a portion of gas flow from said process gas stream fraction into one or more remaining process gas stream fractions.
14. The method of claim 13, wherein said process gas comprises a corrosive gas.
15. The method of claim 13, wherein said process gas is substantially free of particulate matter.
16. The method of claim 13, wherein said balancing gas is substantially inert.
17. The method of claim 13, wherein said balancing gas is substantially free of particulate matter.
18. The method of claim 13, wherein said process gas comprises sulfur trioxide and said balancing gas comprises air.
19. The method of claim 18, further comprising the step of heating said balancing gas stream.
20. The method of claim 13, wherein said process gas comprises ammonia and said balancing gas comprises air.
21. The method of claim 13, wherein said step of dividing said process gas stream into process gas stream fractions is performed with apparatus comprising an inlet conduit for receiving said process gas stream in fluid communication with outlet conduits.
22. The method of claim 21, wherein said step of injecting a balancing gas stream into a process gas stream fraction is performed with apparatus comprising a balancing gas feed conduit in fluid communication with an outlet conduit and a blower.
23. The method of claim 22, wherein said apparatus further comprises a balancing gas controller.
24. The method of claim 13, further comprising the step of dividing said balancing gas stream into balancing gas stream fractions and selectively injecting a balancing gas stream fraction into a process gas stream fraction in an amount sufficient to displace a portion of process gas flow from said process gas stream fraction into one or more remaining process gas stream fractions.
25. The method of claim 24, further comprising the step of maintaining sufficient balancing gas flow in said balancing gas stream fractions to prevent backflow andor stagnation of said processing gas.
26. The method of claim 24, wherein said step of dividing said balancing gas stream into balancing gas stream fractions is performed with apparatus comprising a common balancing gas feed conduit in fluid communication with balancing gas stream fraction conduits.
27. The method of claim 26, wherein said step of selectively injecting a balancing gas stream fraction into a process gas stream fraction is performed with apparatus comprising a balancing gas stream fraction conduit in fluid communication with a blower and a valve.
28. The method of claim 27, wherein said apparatus further comprises a heater in thermal communication with said balancing gas stream fraction conduit and a flow sensor disposed upstream of said heater and said valve.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-13. (canceled)
14. The method according to any one of claims 24 through 33, wherein a weight-average molecular weight of the block copolymer is from approximately 10,000 to approximately 3,000,000.
15. The method according to any one of claims 24 through 33, wherein the block copolymer contains approximately 0.01 to approximately 5 weight % of a hydrophobic segment and approximately 95 to approximately 99.9 weight % of a hydrophilic segment.
16. The method according to any one of claims 24 through 33, wherein the hydrophilic segment is a segment made from a hydrophilic polymer selected from the group consisting of poly-N-vinyl-2-pyrrolidone, poly-N-vinyl-2-piperidone, poly-N-vinyl-2-caprolactum, poly-N-vinyl-3-methyl-2-caprolactum, poly-N-vinyl-3-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-piperidone, poly-N-vinyl-4-methyl-2-caprolactum, poly-N-vinyl-3-ethyl-2-pyrrolidone, poly-N-vinyl-4,5-dimethyl-2-pyrrolidone, polyvinyl imidazole, poly-N\u2014N-dimethyl acrylamide, poly-N-vinyl-N-methyl acetamide, polyvinyl alcohol, polyacrylic acid, polymethacrylic acid, and poly(hydroxyethyl methacrylate), as well as blends and copolymers thereof.
17. A contact lens wetting agent solution, comprising a contact lens wetting agent according to any one of claims 12 through 16.
18. The contact lens wetting agent solution according to claim 17, wherein the contact lens wetting agent solution is a packaging solution or a storage solution.
19. The method of claim 24 wherein said-block copolymer permeates into and is entangled in said silicone hydrogel.
20. The medical material according to claim 19, comprising approximately 0.1 ppm to approximately 30% of the block copolymer.
21. The method according to any one of claims 24-33, wherein the silicone hydrogel is polymerized from a reaction mixture comprising at least one hydrophilic monomer selected from a group consisting of N,N-dimethyl acrylamide (DMA), 2-hydroxyethyl acrylate, glycerol methacrylate, 2-hydroxyethyl methacrylate amide, polyethylene glycol mono methacrylate, methacrylic acid, acrylic acid, N-vinyl pyrrolidone, N-vinyl-N-methyl acetamide, N-vinyl-N-ethyl acetamide, N-vinyl-N-ethyl form amide, N-vinyl formamide, N-2-hydroxyethyl vinyl carbamate, N-carboxy-beta-alanine N-vinylester, reactive polyethylene polyol, hydrophilic vinyl carbonate, vinyl carbamate monomer, hydrophilic oxazolone monomer, hydrophilic oxazoline monomer, and combinations thereof.
22. The method according to any one of claims 24-33, wherein the silicone hydrogel is polymerized from a reaction mixture comprising at least one silicone monomer having a hydroxyl group.
23. The medical material according to claim 22, wherein an amount of component derived from a silicone monomer that is used in the silicone hydrogel is approximately 5 to approximately 95 weight %.
24. A method comprising contacting a silicone hydrogel contact lens with a packaging solution comprising a surface-wetting effective amount of at least one block copolymer comprising one hydrophilic segment and one hydrophobic segment having a weight average molecular weight of 300 to 1800, the block copolymer expressed by formula (b1).
Formula:
wherein in (b1), R1 is one type of group selected from an alkyl group or an alkoxy group;
R2 is one type of group selected from (CH2)n and (CH2)m\u2014O(CH2)n;
m and n are independent, ranging from 1 to 16; a is from 4 to 19; b is from 1 to 6, c is from 1 to 10,000, X is one type of group selected from O, NH, and S; and R3 and R4 represent groups made of monomers with hydrophilicity wherein a monomer is expressed by general formula (n)) under conditions sufficient to associate said block copolymer with said contact lens.
25. The method of claim 24 wherein said surface-wetting effective amount comprises at least about 50 ppm block copolymer.
26. The method of claim 24 wherein said surface-wetting effective amount comprises at least about 10 to about 3000 ppm block copolymer.
27. The method of claim 24 wherein said surface-wetting effective amount comprises about 10 to about 2000 ppm block copolymer.
28. The method of claim 24 further wherein said contacting step further comprising heating the solution and contact lens.
29. The method of claim 28 wherein said heating step comprises at least one heat sterilization cycle.
30. The method of claim 28 wherein said heating step comprises autoclaving.
31. The method of claim 28 where said heating step is conducted at a temperature of at least about 40\xb0 C.
32. The method of claim 28 wherein said heating conducted for at least about 10 minutes.
33. The method of claim 28 wherein said block copolymer is persistently associated with said contact lens over a useful life of the contact lens.