Abstract: The present invention provides a production method of a multifunctional acrylate with a reduced tin content which includes adding an acid to a mixture containing an organotin compound and a multifunctional acrylate and distilling the mixture containing the acid.

Abstract: The present invention provides a production method of a multifunctional acrylate with a reduced tin content which includes adding an acid to a mixture containing an organotin compound and a multifunctional acrylate and distilling the mixture containing the acid.

Abstract: A (meth)acrylate production system having a reactor (A1) provided with a distillation column (2) and a distillation apparatus (B3) provided with a distillation column (4). A condensing apparatus (6) is provided at the top of the distillation column (2).

Abstract: A model verification system includes a formal language conversion part operable to convert model figure data registered as a design pattern in association with a program into formal language expression data based upon an expression format of a predetermined formal language, and a formal language increment part operable to add a modification to a component of the formal language and/or attribute information on the formal language expression data converted by the formal language conversion means to generate formal language expression data of a derivative design. The model verification system conducts refactoring.

Abstract: A process for preparing 4-hydroxybutyl acrylate by transesterifying an alkyl acrylate with 1,4-butanediol in the presence of a dialkyltin oxide such that each of the alkyl groups has 4 to 8 carbon atoms, characterized in that the amount of the dialkyltin oxide is adjusted to 0.00001 to 0.01 moles per one mole of the alkyl acrylate.

Abstract: A model verification system includes a formal language conversion part operable to convert model figure data registered as a design pattern in association with a program into formal language expression data based upon an expression format of a predetermined formal language, and a formal language increment part operable to add a modification to a component of the formal language and/or attribute information on the formal language expression data converted by the formal language conversion means to generate formal language expression data of a derivative design. The model verification system conducts refactoring.

Abstract: A digital wireless receiving apparatus performs AGC control. A desired wave level is detected at a modulator, and AGC control is performed for a high frequency portion by detecting a desired wave level at a demodulator. A tap number of a digital filter in the demodulator is controlled or another analog filter of an intermediate frequency detects an input level of an interfering wave or a desired wave, thereby performing AGC control for the high frequency portion and controlling the tap number of the digital filter at the demodulator.

Abstract: A dental adhesive coating base composition comprising a copolymer represented by formula (I) or (II) in an amount of from 5 to 40 wt % based on the total amounts of the composition; and an oral composition comprising at least one of a copolymer represented by formula (I) and a copolymer represented by formula (II) in an amount of from 5 to 40 wt % based on the total amount of the composition, at least one of a phosphoric acid and tartaric acid present in an amount effective to increase the solubility of fluoride in the composition, up to an amount of 6 wt % or less based on the total amount of the composition; a fluorine-containing compound in an amount effective for dental caries prevention; and a volatile nonaqueous solvent are disclosed: ##STR1## wherein R.sup.11 represents an alkyl group having from 1 to 10 carbon atoms; R.sup.12 represents a lower alkyl group having from 1 to 2 carbon atoms, provided that three R.sup.12 groups must be the same; R.sup.13, R.sup.14, R.sup.15, R.sup.16 and R.sup.

Abstract: This invention relates to a method for the purification of glycidyl acrylate or glycidyl methacrylate. Specifically, the invention effects the purification by using a residual catalyst-inactivating additive and consequently produces highly purified glycidyl acrylate or glycidyl methacrylate containing substantially no epichlorohydrin and having a low chlorine content.

Abstract: This invention provides a method for the manufacture of a high-expansion type absorbent polymer by first causing an absorbent polymer which is obtained by polymerization of a monomer and is possessed of an alkali salt of acrylic acid as a component of polymer to be cross-linked at the time of azeotropic dehydration thereof with a cross-linking agent possessing two or more functional groups in the presence of an inorganic salt and subsequently drying the cross-linked polymer. By the method of this invention, there can be obtained a high-expansion type absorbent material which absorbs water quickly and forms a gel not viscid but permeable to gas. This absorbent material is highly advantageously used as absorbent for sanitary materials free from leaking water and as a water-retaining agent for agricultural applications hardly causing rotton plant roots.

Abstract: Disclosed herein is a fully automatic ultrasonic flaw detection apparatus convenient for flaw detection in a weld zone such as found in an welded iron structure. The apparatus includes a scanner for moving a ultrasonic transmitting and receiving probe in directions parallel to and perpendicular to the longitudinal direction of the object to be inspected or the testpiece, and an information processing unit for controlling the action of the scanner and processing received reflected ultrasonic wave flaw detection data. The probe is alternately moved parallel to and perpendicular to the longitudinal direction of the testpiece according to a predetermined scanning routine to perform rough flaw detection and the results of this rough flaw detection are produced as output. When the presence of flaw is detected during this rough flaw detection routine, the probe is returned to a position necessary to perform precision flaw detection of that flaw.

Abstract: Method and apparatus for automatic ultrasonic flaw detection of pipe welding zones wherein the width of the weld zone is divided into a plurality of subdivisions. The ultrasonic energy received from each of the subdivisions is displayed by employing multichannel gate circuitry providing respective outputs in units of 10% of the height of the echoes in each subdivision on a cathode ray tube in synchronization with signals representative of the longitudinal and lateral position of the probes along the pipe with respect to a reference point. The height of the defective echoes in each gate are printed together with the positions of the probe. The positions of the defects are diagrammed by a computer, thereby enabling high-speed data processing of the flaw detection information, a decrease in the time for the precise flaw detection comparable to conventional manual flaw detection method and apparatus and easy determination of the flaw detection results.