Process for preparing organically modified aerogels using alcohols
    52.
    发明授权
    Process for preparing organically modified aerogels using alcohols 有权
    使用醇制备有机改性气凝胶的方法

    公开(公告)号:US6140377A

    公开(公告)日:2000-10-31

    申请号:US68184

    申请日:1998-09-29

    摘要: The invention relates to a process for the preparation of aerogels having hydrophobic surface groups, consisting ofa) taking a silicate-type lyogel,b) optionally subjecting the lyogel taken in Step a) to a solvent exchange with another solvent,c) surface-modifying the gel obtained in Step a) or b) with at least one C.sub.1 -C.sub.6 -alcohol, andd) drying, under subcritical conditions, the surface-modified gel obtained in Step c).

    摘要翻译: PCT No.PCT / EP96 / 04821 Sec。 371日期:1998年9月29日 102(e)1998年9月29日PCT PCT 1996年11月5日PCT公布。 出版物WO97 / 17287 日期1997年5月15日本发明涉及一种制备具有疏水表面基团的气凝胶的方法,该方法由以下组成:a)取硅酸盐型溶胶凝胶,b)任选地使步骤a)中获得的溶胶凝胶与另一种溶剂进行溶剂交换, c)用至少一种C 1 -C 6醇对在步骤a)或b)中获得的凝胶进行表面改性,和d)在亚临界条件下干燥步骤c)中获得的表面改性凝胶。

    Process for preparing organically modified aerogels using alcohols,
wherein the resultant salts are precipitated
    53.
    发明授权
    Process for preparing organically modified aerogels using alcohols, wherein the resultant salts are precipitated 失效
    使用醇制备有机改性气凝胶的方法,其中所得盐沉淀

    公开(公告)号:US6129949A

    公开(公告)日:2000-10-10

    申请号:US68364

    申请日:1998-10-26

    摘要: The invention concerns a process for preparing organically modified aerogels, in which a) a silicic acid sol with a pH .ltoreq.4.0 is produced from an aqueous potassium silicate solution using at least one organic and/or inorganic acid; b) the resultant silicic acid sol is polycondensed by the addition of a base to form SiO.sub.2 gel; c) the gel produced in step b) is washed with an organic solvent until the water content of the gel is .ltoreq.5 wt %; d) the gel obtained in step c) is surface-modified with at least one C.sub.1-6 alcohol; and e) the surface-modified which are difficult to dissolve in the silicic acid sol. Before step b), the resultant salts, which are difficult to dissolve, are precipitated to the greates possible extent and separated from the silicic acid sol.

    摘要翻译: PCT No.PCT / EP96 / 04820 Sec。 371日期:1998年10月26日 102(e)日期1998年10月26日PCT 1996年11月5日PCT PCT。 第WO97 / 18161号公报 日期1997年5月22日本发明涉及一种制备有机改性气凝胶的方法,其中a)使用至少一种有机和/或无机酸由硅酸钾水溶液产生pH <= 4.0的硅酸溶胶; b)所得硅酸溶胶通过加入基底进行缩聚以形成SiO 2凝胶; c)用有机溶剂洗涤步骤b)中制备的凝胶,直到凝胶的含水量为5重量% d)步骤c)中获得的凝胶用至少一种C 1-6醇进行表面改性; 和e)难以溶解在硅酸溶胶中的表面改性。 在步骤b)之前,所得到的难以溶解的盐被沉淀成可能的程度,并与硅酸溶胶分离。

    Switching device with a feeding circuit for DC power supply to a
subscriber's terminal unit
    56.
    发明授权
    Switching device with a feeding circuit for DC power supply to a subscriber's terminal unit 失效
    具有用于直接供电给馈线终端单元的馈电电路的开关装置

    公开(公告)号:US5570003A

    公开(公告)日:1996-10-29

    申请号:US423245

    申请日:1995-04-13

    CPC分类号: H04M19/005

    摘要: The invention relates to a switching device comprising at least one feeding circuit provided for DC power supply to at least one subscriber's terminal unit. The feeding circuit is especially provided for digital subscribers' terminal units. The invention furthermore relates to the feeding circuit used. There is proposed to provide a first and a second limiting circuit. The first limiting circuit comprises a first series combination of a first supply transistor arrangement and a first supply resistor arrangement to limit a supply current flowing through the first series combination. The second limiting circuit comprises a second series combination of a second supply transistor arrangement and a second supply resistor arrangement to limit a supply current (Is) flowing through the second series combination. A potential (V0) present on the control input of the second supply transistor arrangement depends on the voltage (Ur) present on the first series combination.

    摘要翻译: 本发明涉及一种开关装置,其包括至少一个馈送电路,其被提供用于至少一个用户终端单元的DC电力供应。 馈电电路特别适用于数字用户的终端设备。 本发明还涉及使用的馈电电路。 提出了提供第一和第二限制电路。 第一限制电路包括第一电源晶体管布置和第一电源电阻器布置的第一串联组合,以限制流过第一串联组合的电源电流。 第二限制电路包括第二电源晶体管布置和第二电源电阻器布置的第二串联组合,以限制流过第二串联组合的电源电流(Is)。 存在于第二电源晶体管装置的控制输入上的电位(V0)取决于存在于第一串联组合上的电压(Ur)。