公开(公告)号：DE3927916A1

公开(公告)日：1991-02-28

申请号：DE3927916

申请日：1989-08-24

Applicant: BASF AG

Inventor： STECK WERNER DR ,  RUST HARALD ,  LERMER HELMUT DR ,  NAEUMANN FRITZ DR

IPC: C07C253/34 ,  C07C255/50

Abstract: A process for the separation of ortho-, meta- and para-tolunitrile from ternary mixtures of isomers entails removing ortho-tolunitrile from these mixtures by distillation under pressures of from 102 and 105 Pa and with a reflux ratio of from 1:1 to 200:1, and distilling the remaining binary mixture of meta- and para-tolunitrile to concentrate to more than 75 mol-% para-tolunitrile, and freezing out the paratolunitrile at below 26 DEG C., and a process for the preparation of suitable ternary mixtures of isomers entails isomerization of pure ortho-, meta- or para-tolunitrile or mixtures thereof at from 380 DEG to 580 DEG C. on zeolite catalysts.

公开(公告)号：DE3581161D1

公开(公告)日：1991-02-07

申请号：DE3581161

申请日：1985-10-10

Applicant: BASF AG

Inventor： STECK WERNER DR ,  JAKUSCH HELMUT DR

IPC: C01G49/00 ,  C09D5/23 ,  C09D7/12 ,  G11B5/706 ,  G11B5/712 ,  H01F1/11

Abstract: Ferrimagnetic particles which are useful as magnetic material for magnetic recording media and consist of a core of a magnetic material exhibiting multiaxial anisotropy and a coating which surrounds the core and is composed of a magnetic material possessing uniaxial anisotropy, and a process for their preparation.

公开(公告)号：DE3903622A1

公开(公告)日：1990-08-09

申请号：DE3903622

申请日：1989-02-08

Applicant: BASF AG

Inventor： HESSE MICHAEL DR ,  LERMER HELMUT DR ,  STECK WERNER DR ,  FISCHER ROMAN DR ,  MUELLER HERBERT DR ,  SCHARF EMIL DR

IPC: C07D487/08

公开(公告)号：DE3843389A1

公开(公告)日：1990-06-28

申请号：DE3843389

申请日：1988-12-23

Applicant: BASF AG

Inventor： HESSE MICHAEL DR ,  LERMER HELMUT DR ,  STECK WERNER DR ,  SCHAPER MICHAEL DR

IPC: C07D307/62

Abstract: Process for the preparation of ascorbic acid, of the formula I, which is characterised in that 2-keto-L-gulonic acid derivatives of the formula II in which R can denote H, alkyl or aryl, are reacted in the presence of zeolites as catalysts.

公开(公告)号：DE3472727D1

公开(公告)日：1988-08-18

申请号：DE3472727

申请日：1984-12-10

Applicant: BASF AG

Inventor： STECK WERNER DR ,  SARNECKI WILHELM DR ,  JAKUSCH HELMUT DR ,  MAROSI LASZLO DR

IPC: C01G49/00 ,  C01G49/02 ,  C01G51/00 ,  C01G51/04 ,  G11B5/706 ,  H01F1/10 ,  H01F1/11

公开(公告)号：DE3470810D1

公开(公告)日：1988-06-01

申请号：DE3470810

申请日：1984-12-10

Applicant: BASF AG

Inventor： STECK WERNER DR ,  JAKUSCH HELMUT DR ,  MAROSI LASZLO DR

IPC: C01G49/00 ,  C01G49/02 ,  C01G51/04 ,  G11B5/706 ,  H01F1/10 ,  H01F1/11

公开(公告)号：DE3616096A1

公开(公告)日：1987-11-19

申请号：DE3616096

申请日：1986-05-13

Applicant: BASF AG

Inventor： SCHWAB EKKEHARD DR ,  STECK WERNER DR ,  SCHLOESSER WILHELM ,  FESER RAINER DR

IPC: C01G49/02 ,  C01G49/00 ,  G11B5/706 ,  G11B5/712 ,  H01F1/11 ,  C01G49/06 ,  C01G51/04 ,  C09C1/24 ,  C09C3/06

Abstract: Acicular, magnetic iron oxide consisting of a core of gamma-iron(III) oxide and a ferrite shell containing a total of from 0.4 to 12% by weight of cobalt(II) ions and from 0.1 to 15% by weight of iron(II) ions, the percentages being based on the total amount of magnetic material, is prepared by a process in which an iron(II) hydroxide precipitate is applied to the gamma-iron(III) oxide core in a first stage and an iron-(II)/cobalt hydroxide precipitate is applied to the said core in a second stage, and the core is then converted to the ferrite shell by oxidation.

公开(公告)号：DE3345531A1

公开(公告)日：1985-06-27

申请号：DE3345531

申请日：1983-12-16

Applicant: BASF AG

Inventor： STECK WERNER DR ,  JAKUSCH HELMUT DR ,  MAROSI LASZLO DR

IPC: C01G49/00 ,  C01G49/02 ,  C01G51/04 ,  G11B5/706 ,  H01F1/10 ,  H01F1/11 ,  B05D5/12 ,  G11B5/62 ,  H01F10/18

公开(公告)号：DE3163612D1

公开(公告)日：1984-06-20

申请号：DE3163612

申请日：1981-06-15

Applicant: BASF AG

Inventor： STECK WERNER DR ,  ROLLER HERMANN ,  SARNECKI WILHELM DR ,  BALZ WERNER DR

IPC: B22F1/02 ,  B22F9/24 ,  G11B5/70 ,  H01F1/06 ,  H01F1/09

Abstract: Ferromagnetic metal particles, consisting essentially of iron and comprising a core, containing not less than 85% by weight of metallic iron, and an iron oxide plus chromium oxide surface layer surrounding this core, which layer additionally contains one or more elements selected from the group comprising zinc, phosphorus in the form of phosphate, aluminum, calcium, strontium, barium, cadmium, lead, cobalt and nickel in a total amount of not more than 9.5% by weight, based on the total amount of the metal particles, and a process for the production of such particles.

公开(公告)号：DE3067268D1

公开(公告)日：1984-05-03

申请号：DE3067268

申请日：1980-08-21

Applicant: BASF AG

Inventor： STECK WERNER DR ,  SARNECKI WILHELM DR ,  MAROSI LASZLO DR ,  OHLINGER MANFRED DR ,  AUTZEN HORST DR

IPC: G11B5/706 ,  B22F9/22 ,  C01G49/02 ,  C09D5/23 ,  C09D7/12 ,  G11B5/70 ,  H01F1/06