1. A linear compressor comprising:
a linear motor comprising a stator and a magnet, said linear motor configured to generate a linear driving force;
a stationary cylinder having a first compression chamber formed therein, an outlet valve being provided at a front portion of the stationary cylinder;
a moving piston movable forward and backward by said linear motor, by the magnet of the linear motor being connected to said moving piston to compress a fluid in the first compression chamber, the moving piston having a second compression chamber therein,
a first valve provided at a front portion of the moving piston such that the first compression chamber is provided in the stationary cylinder in a space between the outlet valve and the first valve; and
a stationary piston fixedly positioned in the compressor, the stationary piston being fitted in the moving piston so that the fluid in the second compression chamber is compressed as the moving piston is reciprocated, the stationary piston having an inlet flow channel provided therein so that the fluid is introduced through the inlet flow channel; and
a second valve provided at the stationary piston such that the second compression chamber is provided between the first valve and the second valve;
wherein the stationary piston is spaced from a rear end of the stationary cylinder in an axial direction of the stationary cylinder, and
wherein the moving piston comprises:
a piston part that is linearly movable, a portion of the piston part extending into the stationary cylinder; and
a moving cylinder part connected to a rear of the piston part, the stationary piston being positioned within the moving cylinder.
2. The compressor as set forth in claim 1, the outlet valve being opened when the pressure in the first compression chamber is more than a prescribed pressure.
3. The compressor as set forth in claim 1,
wherein the piston part is provided at the rear thereof with a flange, the flange being fixed to a moving member of the linear motor, and
wherein the moving cylinder part is fixedly attached to the rear of the flange.
4. The compressor as set forth in claim 1, wherein the first valve is opened when the moving piston is moved backward toward the stationary piston.
5. The compressor as set forth in claim 1, wherein the second valve is opened when the moving piston is moved forward toward the stationary cylinder.
6. The compressor as set forth in claim 1, wherein the first and second valves comprise plate valves provided at the front ends of the moving piston and the stationary piston, respectively.
7. A linear compressor comprising:
a linear motor comprising a stator and a magnet, said linear motor configured to generate a linear driving force;
a stationary cylinder having a first compression chamber formed therein, an outlet valve being provided at a front portion of the stationary cylinder;
a moving piston movable forward and backward by said linear motor, by the magnet of the linear motor being connected to said moving piston to compress a fluid in the first compression chamber, the moving piston having a second compression chamber therein,
a first valve provided at a front portion of the moving piston such that the first compression chamber is provided in the stationary cylinder in a space between the outlet valve and the first valve; and
a stationary piston fixedly positioned in the compressor, the stationary piston being fitted in the moving piston so that the fluid in the second compression chamber is compressed as the moving piston is reciprocated, the stationary piston having an inlet flow channel provided therein so that the fluid is introduced through the inlet flow channel; and
a second valve provided at the stationary piston such that the second compression chamber is provided between the first valve and the second valve; and
a valve-actuating unit that opens and closes the second valve.
8. The compressor as set forth in claim 7,
wherein the second valve comprises a plate valve provided at the front part of the stationary piston, and
wherein the valve-actuating unit comprises: an actuator that generates a driving force in response to an external signal; and a push rod that connects the actuator and the plate valve, the pushrod moving the plate valve in response to the operation of the actuator.
9. A linear compressor comprising:
a first cylinder;
a linear motor comprising a stator and a magnet configured to generate a linear driving force;
an outlet valve positioned at a front part of the first cylinder;
a first piston connected to the magnet of the linear motor, the first piston being movable forward and backward in the first cylinder, the first piston having a first flow channel provided therein, the first flow channel communicating with the interior of a first cylinder;
a first inlet valve disposed at a front part of the first piston, the first inlet valve configured for opening and closing the first flow channel;
a second cylinder connected to a rear part of the first piston so that the second cylinder is moved together with the first piston, the second cylinder having a second flow channel provided therein, the second flow channel communicating with the first flow channel;
a back cover disposed in the compressor, the back cover having an inlet port provided therein;
a second piston fixedly attached to the back cover, the second piston being fitted in the second cylinder such that fluid in the first and second flow channels is compressed as the first piston and the second cylinder are reciprocated, the second piston having a third flow channel provided therein, the inlet port of the back cover being connected to the second flow channel via the third flow channel; and
a second inlet valve disposed at a front part of the second piston, the second inlet valve configured for opening and closing the third flow channel;
wherein the stationary piston is spaced from a rear end of the stationary cylinder in an axial direction of the stationary cylinder,
wherein the moving piston comprises:
a piston part that is linearly movable, a portion of the piston part extending into the stationary cylinder; and
a moving cylinder part connected to a rear of the piston part, the stationary piston being positioned within the moving cylinder.
10. The compressor as set forth in claim 9,
wherein the first piston is provided at a rear part thereof with a flange, the flange being fixed to a movable member of the linear motor, and
wherein the second cylinder is fixedly attached to a rear part of the flange.
11. The compressor as set forth in claim 9, wherein the first inlet valve is opened when the first piston is moved backward toward the second piston.
12. The compressor as set forth in claim 9, wherein the second inlet valve is opened when the first piston and the second cylinder are moved forward toward the first cylinder.
13. The compressor as set forth in claim 9, wherein the first and second inlet valves comprise plate valves.
14. The compressor as set forth in claim 9, further comprising a valve-actuating unit that opens and closes the second inlet valve.
15. The compressor as set forth in claim 14,
wherein the second inlet valve comprises a plate valve, and
wherein the valve-actuating unit comprises: an actuator that generates a driving force in response to an external signal; and a push rod that connects the actuator and the plate valve, the pushrod moving the valve in response to the operation of the actuator.
16. A linear compressor comprising:
a linear motor comprising a stator and a magnet and configured to generate a liner driving force;
a stationary cylinder having a first compression chamber formed therein an outlet valve provided at a front part of the stationary cylinder;
a moving piston movable forward and backward along with the linear motor, the magnet of the linear motor being connected to the moving piston such that fluid in the first compression chamber of the stationary cylinder is compressed, the moving piston having a second compression chamber provided therein, the second compression chamber communicating with the first compression chamber; and
a stationary piston movable into the second compression chamber for compressing fluid in the second compression chamber as the moving piston is moved forward and backward;
wherein the stationary piston is spaced from a rear end of the stationary cylinder in an axial direction of the stationary cylinder,
wherein the moving piston comprises:
a piston part that is linearly movable, a portion of the piston part extending into the stationary cylinder; and
a moving cylinder part connected to a rear of the piston part, the stationary piston being positioned within the moving cylinder.
17. The compressor as set forth in claim 16, wherein the moving piston is provided, at the position where the second compression chamber communicates with the first compression chamber, with a first valve.
18. The compressor as set forth in claim 16, wherein the stationary piston has an inlet flow channel provided therein, and the stationary piston is provided, at the position where the inlet flow channel communicates with the second compression chamber, with a second valve.
19. The compressor as set forth in claim 18, further comprising a valve-actuating unit that opens and closes the second valve.
20. The compressor as set forth in claim 19, wherein the outlet valve comprises:
an inner outlet cover mounted to a cylinder block to communicate with the stationary cylinder and having a fluid outlet formed at one side thereof;
an outer outlet cover disposed outside the inner outlet cover and spaced from the inner outlet cover; and
a valve body elastically supported by a spring disposed in the inner outlet cover, that opens and closes the stationary cylinder.
21. An operation process of a linear compressor, comprising:
forwardly moving a moving piston and a moving cylinder toward an outlet valve;
compressing fluid in a first compression chamber comprising a stationary cylinder;
discharging fluid in the first compression chamber through the outlet valve;
introducing fluid from outside of a back cover into a second compression chamber through an inlet port of the back cover and a third flow channel formed in a stationary piston;
backwardly moving the moving piston and the moving cylinder toward the inlet port of the back cover;
compressing the fluid in the second compression chamber;
introducing the compressed fluid in the second compression chamber into the first fluid compression chamber; and
positioning the stationary piston at a location spaced from a rear end of the stationary cylinder, in an axial direction of the stationary cylinder.
22. The operation process of a linear compressor as set forth in claim 21, the operation process further comprising:
closing a part of a first valve corresponding to a first flow channel formed in the moving piston;
opening a part of a second valve corresponding to the third flow channel;
closing a part of the second valve corresponding to the third flow channel; and
opening a part of the first valve corresponding to the first flow channel toward the outlet valve.
23. The operation process of a linear compressor as set forth in claim 21, the forwardly moving comprising moving the moving piston forwardly with respect to the stationary cylinder.
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. Method for identifying cytosine methylation patterns in genomic DNA samples, said method comprising the steps of:
a) chemically treating a genomic DNA sample in such a way that cytosine and 5-methylcytosine react differently and a different base pairing behavior of the two products is obtained in the duplex;
b) enzymatically amplifying portions of the thus-treated DNA sample;
c) binding the amplified portions of the thus-treated DNA sample to a surface;
d) contacting a set of probes of different nucleobase sequences, each of which contains the dinucleotide sequence 5\u2032-CpG-3\u2032 at least once, to the immobilized DNA samples for hybridization to distinguish methylated and nonmethylated cytosines in said genomic DNA sample;
e) removing any non-hybridized probes from the immobilized DNA samples;
f) analyzing the hybridized probes in a mass spectrometer, wherein the position of the hybridized probes on the surface permits a classification of the immobilized DNA sample hybridized thereto;
g) assigning a peak pattern obtained from the mass spectra to a methylation pattern for the immobilized DNA and comparing the peak pattern with a database to identify cytosine methylation patterns in the genomic DNA sample.
2. Method according to claim 1, further characterized in that one or more amplified genomic DNA fragments are immobilized in c) by hybridization with complementary oligonucleotide or PNA sequences, which are covalently bound to the surface.
3. Method according to claim 2, further characterized in that a cross-linking of the genomic DNA fragments with the oligonucleotide or PNA sequences bound to the surface results after the hybridization.
4. Method according to claim 3, further characterized in that covalent chemical bonds are formed for the cross-linking.
5. Method according to claim 3, further characterized in that electrostatic interactions are formed for the cross-linking.
6. Method according to claim 3, further characterized in that the oligonucleotide or PNA sequences bound to the surface contain 5-bromouracil structural units.
7. Method according to claim 1, further characterized in that the immobilized complementary oligonucleotide sequences contain modified bases, ribose or backbone units.
8. Method according to claim 1, further characterized in that the genomic DNA sample is propagated in b) in the form of several amplified fragments, so that at least 0.01% of the total genome is amplified.
9. Method according to claim 1, further characterized in that the mixture of amplified DNA fragments is bound to a surface, on which a multiple number of different points is arranged, each of which can bind different portions of the amplified DNA sample.
10. Method according to claim 1, further characterized in that a set of probes is used in d), which contains the dinucleotide sequence 5\u2032-CpG-3\u2032 only once in each probe and the probes otherwise contain either no cytosine or no guanine bases.
11. Method according to claim 1, further characterized in that a bisulfite or pyrosulfite or disulfite solution or a mixture of the indicated solutions is used together with other reagents for the specific or sufficiently selective conversion of cytosine to uracil.
12. Method according to claim 1, further characterized in that the surface used for the immobilization of amplified sample DNA is also the sample holder for a mass spectrometer.
13. Method according to claim 1, further characterized in that the surface used for the immobilization of amplified sample DNA is introduced as a whole, prior to f), onto a sample holder for a mass spectrometer.
14. Method according to claim 1, further characterized in that the hybridized probes are stripped from the immobilized amplified DNA samples before, after or by contact with a matrix.
15. Method according to claim 1, further characterized in that the probes are nucleic acids, which bear one or more mass tags.
16. Method according to claim 15, further characterized in that one or more mass tags are also charge tags.
17. Method according to claim 15, further characterized in that the probes also bear a charge tag.
18. Method according to claim 1, further characterized in that the probes are modified nucleic acid molecules.
19. Method according to claim 2, further characterized in that nucleic acid molecules are selected from the group consisting of PNAs, alkylated phosphorothioate nucleic acids and alkyl phosphonate nucleic acids.
20. Method according to claim 1, further characterized in that the probes are prepared by combinatory synthesis.
21. Method according to claim 20, further characterized in that different base structural units are labeled in such a way that each of the probes synthesized from them can be distinguished by their mass in the mass spectrometer.
22. Method according to claim 1, further characterized in that the probes are prepared as sublibraries and these are provided with different mass andor charge tags.
23. Method according to one of the preceding claims, further characterized in that matrix-assisted laser desorptionionization mass spectrometry (MALDI) is conducted in f).