摘要:
Affinity chromatography matrixes and immobilized enzymes are provided in which the solid support is a covalently bound, non-crosslinked polyethyleneimine bonded phase.
摘要:
Quaternized non-crosslinked polyethyleneimine silica based solid supports are useful strong anion exchangers for column chromatography separation and purification of proteins and have high binding capacity at high pH, the ability to bind basic proteins having high pH isoelectric points and are rapidly equilibrated and are essentially non-titratable.
摘要:
Affinity chromatography matrixes and immobilized enzymes are provided in which the solid support is a covalently bound, non-crosslinked polyethyleneimine bonded phase.
摘要:
Addition of non-nitrogen containing weak acids to amine-containing alkaline strippers for photoresists produce stripper compositions able to strip highly cross-linked or hardened photoresist films without producing any substantial metal corrosion. Weak acids useful in the stripping compositions include those having a pK in aqueous solution of 2.0 or higher and an equivalent weight of less than about 140 and are employed in an amount to neutralize from about 19% to about 75% of the amine present in the stripper composition.
摘要:
Photosensitive solubilization inhibitor compounds of the formula ##STR1## wherein: x is an integer equal to the valence or functionality of the radical R, andR is a radical selected from the group consisting of the residue of a mono-, di-, tri- or polyfunctional alkanol or silicon-containing alkanol and is attached to the oxy atom of the carboxyl group through a carbon atom.Positive deep ultra-violet photoresists which are base developable comprise base soluble polymers and the photosensitive solubilization inhibition agents. Lithographic resist images are formed with the deep ultra-violet photoresists upon exposure to deep ultra-violet light.
摘要:
System, apparatus and method for efficiently and effectively isolating analytes from a liquid sample by solid phase extraction comprises a workstation platform with a plurality of suction providing stations for receiving either or both a detachably mounted collection chamber housing a removable collection vessel and membrane holder with removable, screen supported disc membrane, the holder having an inlet opening for receiving a liquid and a passageway through the screen supported disc membrane to an exit port for flow and collection, at the appropriate time, of analytes, extraction solvent, or liquid sample. The membrane holder is adapted to be releasably mounted into either the suction stations or the collection chamber. The removable collection vessel in the collection chamber enables prompt, timely, safe and effective removal of solvent, analyte or liquid from the system. The workstation platform is preferably rotatable for ease of access to the plurality of suction providing stations.
摘要:
Sulfonic derivatives of N-acylated covalently bound, non-crosslinked polyethyleneimine bonded phase silicas of the formula: ##STR1## wherein ##STR2## is the backbone of a silica gel or glass, n is an integer such that the polyethyleneiminopropyl silane group has an average molecular weight of from about 400 to about 1800; q is an integer of zero or one; R is selected from the group consisting of hydrogen, --CH.sub.2).sub.x H or --CH.sub.2).sub.m COOH where X is an integer of 1 or 2 and m is an integer of zero or 1; when R is hydrogen or --CH.sub.2).sub.x H then R.sup.1 is --CH.sub.2).sub.p COOH where p is an integer of zero or 1, and when R is --CH.sub.2).sub.m COOH then R.sup.1 is selected from the group consisting of hydrogen or --CH.sub.2).sub.y H where y is an integer of zero or 1, are especially useful as solid phases for the purification and separation of proteins having isoelectric points of below about 5.
摘要:
Aqueous alkaline cleaning solutions for cleaning microelectronic substrates and maintaining substrate surface smoothness comprise a metal ion free base, a nonionic surfactant and a component to reduce or control the pH of the cleaning solution to a pH within the range of from about pH 8 to about pH 10.
摘要:
2-diazo-1-ones are useful deep UV photoresist solubility modification agents exhibiting improved photosensitivity allowing shorter deep UV exposure times to achieve the same extent of photoreaction as with prior art solubility modification agents. The 2-diazo-1-one solubility modification agents when used as photoactive solubility modification components in photoresist compositions permit the photoresist compositions to act as either positive or negative photoresist compositions depending upon the developer employed, namely, as a positive resist when a metal ion containing developer is employed and as a negative resist when a metal ion free developer is employed.
摘要:
Photosensitive solubilization inhibitor compounds of the formula ##STR1## wherein: x is an integer equal to the valence or functionality of the radical R, andR is a radical selected from the group consisting of the residue of a mono-, di-, tri- or polyfunctional alkanol or silicon-containing alkanol and is attached to the oxy atom of the carboxyl group through a carbon atom.Positive deep ultra-violet photoresists which are base developable comprise base soluble polymers and the photosensitive solubilization inhibition agents. Lithographic resist images are formed with the deep ultra-violet photoresists upon exposure to deep ultra-violet light.