Abstract: A method for determining wafer cleanliness by fluorometric monitoring of the impurities in the semiconductor chip wafer rinse solution. A clean chip is indicated by a leveling off of increased concentration of impurities as the rinsing of the chip progresses. A method for optimizing reuse or recyling of the water discharged from the rinse process which accurately measures the contaminants in that water.
Abstract: The concentration of the active ingredient in a rolling oil emulsion can be rapidly determined, and correction of the concentration of the active ingredient can be undertaken by measuring the measuring the amount of light reflected from the emulsion at the peak absorbing wavelength of the dye to obtain a first reflectance value and measuring the amount of light reflected from said emulsion at a wavelength other than the peak absorbing wavelength of the dye to obtain a second reflectance value for at least two different concentrations of the rolling oil in the rolling oil emulsion, establishing a calibration curve, and then monitoring the rolling oil emulsion in like manner. The results may be utilized to feed additional additive to the emulsion, or may be used to feed water into the emulsion system.
Abstract: The present invention provides a method of monitoring a papermaking system and unit operations contained therein to optimize the overall papermaking process. The method comprises employing a fluorescent tracer that is selectively carried through the entire papermaking system or in a specific unit operation and is sufficiently inert and sufficiently stable under the environmental and chemical conditions of the system from its addition point to the sampling point. A sample is withdrawn from the papermaking environment (either via `grab` or on-line side stream sampling) and the withdrawn sample subjected to analysis. The analysis comprises comparing the tracer concentration to a standard to determine the concentration of tracer in the sample and/or determining the time of first appearance of said tracer from addition point to the sampling point and/or subsequent decay of said tracer concentration at the sampling point.
Abstract: A process for treating recycled coated broke which has been re-pulped to a slurry for the purpose of recycling the coated broke as cellulose fiber to the paper machine by the addition of a water-soluble polymer dispersion is claimed. The water-soluble polymer is formed by polymerizing a water-soluble mixture which comprises: (a) a cationic monomer represented by the following general formula (I): ##STR1## wherein R.sub.1 is H or CH.sub.3 ; each of R.sub.2 and R.sub.3 is an alkyl group having 1 to 2 carbon atoms; R.sub.4 is H or an alkyl group of 1 to 2 carbon atoms; A' is an oxygen atom or NH; B' is an alkylene group of 2 to 4 carbon atoms or a hydroxypropylene group; and X.sup.
Abstract: The present invention is a method of preventing fouling and coke formation on the high temperature sections of hydrocarbon processing equipment which comes into contact with a hydrocarbon fluid. The method comprises adding to a carrier prior to the carrier coming into contact with the high temperature sections of such equipment, an effective amount of an antifoulant in its vapor phase selected from the group consisting of tri-tertiary-butylphenol phosphate esters and compounds having the formula I: ##STR1## wherein Q is Z, or R with the proviso that two occurrences of Q are Z, R is hydrogen, or a straight or branched alkyl group having from 1 to 7 carbon atoms, and only one or two occurrences of R may be alkyl. Z is represented by the formula II: ##STR2## wherein R.sub.2 and R.sub.3 are the same as R and only one or two occurrences of each of R.sub.2 and R.sub.3 may be alkyl, and "n" is a whole number of from 1 to 9, and mixtures thereof.
Abstract: Primary amines, ammonia, or mixtures thereof can be detected using a reagent comprising from about 650 ppm to about 25 percent by weight of phthalic dicarboxyaldehyde; from about 74 to about 99.88 percent by weight of an alkali metal borate; and, from about 550 ppm to about 22 percent by weight of a nucleophile.
Type:
Grant
Filed:
July 12, 1996
Date of Patent:
January 12, 1999
Assignee:
Nalco Chemical Company
Inventors:
Martin R. Godfrey, Donald E. Govoni, Linda M. Link
Abstract: An improved papermaking process comprising forming an aqueous coated broke papermaking slurry and adding a blend of a water-soluble dispersion polymer and a coagulant to the slurry to increase retention and/or drainage is disclosed. After addition of the polymers, the slurry is drained to form a sheet, and the sheet is dried.
Abstract: A liquid slurry of bentonite which comprises bentonite, water, a polyacrylate, and a sodium salt of silicic acid. Optionally, a sulfonate is present in an amount of between about 10 to about 30% by weight.
Abstract: The present invention provides a method for removing secondary fiber contaminants from paper mill process waters comprising adding a polyvinyl chloride, a cationic polymeric coagulant and a polymeric flocculant to paper mill process waters containing secondary fiber contaminants in an amount sufficient to agglomerate the secondary fiber contaminants to larger particles sizes, and removing the secondary fiber contaminants from the process water by a dissolved air flotation clarification technique. The addition of particulate polyvinyl chloride in combination with a polymeric coagulant and flocculant prior to the DAF clarification process causes the contaminants to become preferentially coated with the polyvinyl chloride particles. This coating is what causes the subsequent removal of the secondary fiber contaminants in the DAF clarification process to be more effective.
Type:
Grant
Filed:
August 20, 1996
Date of Patent:
August 25, 1998
Assignee:
Nalco Chemical Company
Inventors:
Carol S. Greer, Ann M. Capozzi, Linda S. Wilkins
Abstract: Described is a process for preparing a three-dimensional article of a lyotropic polymer comprising the steps of (a) forming a shaped article of a liquid crystalline solution of a lyotropic polymer; (b) washing the shaped article with a washing fluid under conditions sufficient to reduce the solvent content of the article to less than about 2,000 parts per million, wherein the dimensions of the washed article are no less than 0.05 inches by 0.05 inches by 0.05 inches. Such articles are useful for many applications, particularly those requiring fire- and/or heat-resistance.
Type:
Grant
Filed:
October 28, 1994
Date of Patent:
August 4, 1998
Assignee:
The Dow Chemical Company
Inventors:
Arie Cohen, Myrna Serrano, Norman L. Madison, deceased, Peter E. Pierini, Ritchie A. Wessling, Donald E. McLemore, Donald L. Schmidt
Abstract: Processes for preparing 5-substituted pyrrolo[2,3-d]pyrimidines which are useful as intermediates for the preparation of pyrrolo[2,3-d]pyrimidine antineoplastic agents or as antineoplastic agents themselves are provided.
Abstract: A stereoselective glycosylation process for preparing beta-anomer enriched 2'-deoxy-2',2'-difluoropyrimidine nucleosides and 2'-deoxy-2'-fluoropyrimidine nucleosides which involves reacting an alpha-anomer enriched 2-deoxy-2,2-difluorocarbohydrate or 2-deoxy-2-fluorocarbohydrate with at least a molar equivalent of a pyrimidine nucleobase derivative in a low freezing inert solvent.
Abstract: Processes for preparing 5-substituted pyrrolo[2,3-d]pyrimidines which are useful as intermediates for the preparation of pyrrolo[2,3-d]pyrimidine antineoplastic agents or as antineoplastic agents themselves are provided.
Abstract: This invention provides 2',3'-dideoxy-2',2'-difluoronucleosides of the structure ##STR1## wherein R.sup.1 -R.sup.4 are defined in the specification. These compounds have been shown to be useful for treating a variety of vital infections in experimental animals as well as having antineoplastic activity against various mouse tumors.
Abstract: This invention provides a process for preparing gemcitabine hydrochloride which comprises deblocking .beta.-1-(2'-deoxy-2',2'-difluoro-3',5'-di-O-benzoyl-D-ribofuranosyl)-4-am inopyrimidin-2-one with a catalytic amount of an alkylamine in the presence of methanol or ethanol in an environment essentially free of water; treating the resulting solution with hydrochloric acid and an antisolvent; and recovering the resulting solid gemcitabine hydrochloride.
Abstract: A process for the preparation of a 2-substituted-3,3-difluorofuran using diethyl ammonium sulfur trifluoride (DAST) and pyridine hydrogen fluoride. The process is particularly useful for producing a 2',2'-difluoronucleoside, particularly 1-(2',2'-difluoro-.beta.-D-arabinofuranosyl)cytosine (also known as 2'-deoxy-2',2'-difluorocytidine), a known antiviral and antitumor agent.
Abstract: A process for preparing 2,2-difluoroketene silyl acetals and .alpha.,.alpha.-difluoro-.beta.-silyloxy-1,3-dioxolane-4-propanoic acid esters using these acetals.
Abstract: Processes for preparing 5-substituted pyrrolo[2,3-d]pyrimidines which are useful as intermediates for the preparation of pyrrolo[2,3-d]pyrimidine antineoplastic agents or as antineoplastic agents themselves are provided.
Abstract: A process for the preparation of 1-(2'-deoxy-2', 2'-difluoro-D-ribo-pentofuranosyl)-cytosine (VI) from 2-deoxy-2,2-difluoro-.beta.-D-ribo-pentopyranose (I). The process uses a tritylation reaction (Step 3) for preparing 2-deoxy-2,2-difluoro-5-O-triphenylmethyl-ribo-pentofuranose (II) as a key intermediate. The 1-(2'-deoxy-2', 2'-difluoro-D-ribo-pentofuranosyl)-cytosine (VI) is an antiviral and anti-cancer agent.