Method of making magnetic recordings which cannot be altered without it being noticed
    3.
    发明授权
    Method of making magnetic recordings which cannot be altered without it being noticed 失效
    制作磁记录的方法,如果没有被注意到,则不能改变

    公开(公告)号:US3883892A

    公开(公告)日:1975-05-13

    申请号:US40697273

    申请日:1973-10-16

    Applicant: BASF AG

    CPC classification number: G11B23/281 G03G5/16 G11B5/64 G11B5/70 G11B5/706

    Abstract: The invention relates to a method of recording magnetic signals on magnetic recording media containing an exchange-anisoptropic material at a temperature lower than, equal to or higher than the Neel temperature of this magnetic material. After the recording has been made, the magnetic recording medium is heated to a temperature equal to, or higher than, the Neel temperature, then cooled down to a temperature below the Neel temperature and the recording temperature, following which it is provided with an indicator which betrays re-heating. The method is suitable for the space-saving and, at the same time, authentic recording and storage of all data and images which are to be preserved without risk of falsification.

    Abstract translation: 本发明涉及一种在低于等于或高于该磁性材料的Neel温度的温度下将磁信号记录在含有交换异向材料的磁记录介质上的方法。 在记录完成之后,将磁记录介质加热到等于或高于Neel温度的温度,然后冷却到低于Neel温度和记录温度的温度,随后设置有指示器 它背叛了再加热。

    Production of phosphonitrilic chlorides
    7.
    发明授权
    Production of phosphonitrilic chlorides 失效
    生产磷酸氯化物

    公开(公告)号:US3656916A

    公开(公告)日:1972-04-18

    申请号:US3656916D

    申请日:1970-04-08

    Applicant: BASF AG

    CPC classification number: C01B21/0986

    Abstract: Phosphonitrilic chlorides having the general formula: PNCl2)n where n denotes an integer of at least 3 and which contain a high proportion of trimeric and tetrameric cyclic phosphonitrilic chlorides are prepared by reaction of phosphorus pentachloride with ammonia in an inert solvent. The solution should contain not more than 5 moles of phosphorus pentachloride per liter. Ammonia is introduced at a rate not exceeding 0.12 liter per minute per mole of the phosphorus pentachloride contained in the whole solution until one tenth to one third of the total amount of ammonia required has been introduced.

    Abstract translation: 具有以下通式的膦酰氯:PNCl2)n其中n表示至少3的整数,并且含有高比例的三聚和四聚环状膦酰氯是通过在惰性溶剂中与五氯化磷反应制备的。 该溶液每升应含有不超过5摩尔的五氯化磷。 以不超过0.12升/分钟的摩尔量,每摩尔包含在整个溶液中的五氯化磷的量引入氨,直到引入所需氨的总量的十分之一至三分之一。

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