Irradiation at 300 nm converts the trans cinnamide side chain of structure 2 to the cis isomer of structure 3, while the reverse process occurs at 254 nm.
In this case, however, the orientation of the cis double bond prevents the side chain inserting into the cavity and so in that mode the machine is turned off. By contrast, the trans alkene moiety does allow insertion, and so in this mode the machine is turned on. (...) The photoisomerisation of the trans cinnamide side chain of structure 2 and the cis isomer of structure 3 provides the machine with an on/off switch.
"Chemistry" 2e - Blackman, A., Bottle, S., Schmid, S., Mocerino, M., Wille, U.
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La Mode nationale, no. 50, 15 décembre 1894, Paris. no. 2. — Carré en guipure sur filet. Modèle de Mme Marchais, 46, rue de Clichy, à Paris. Bibliothèque nationale de France
Explication des gravures:
No. 2. — Carré en guipure sur filet (Modèle de Mme Marchais, 46, rue de Clichy). Après avoir fait voire carré, montez-le sur un cadre en fil de laiton ou sur un métier, a fin de bien le tendre, ce qui facilite le travail et en fait la régularité. Pour broder le filet, prenez du fil à dentelle, bien brillant, puis commencez à faire tous les contours au point de reprise, ensuite remplissez tous les motifs au point de toile.
Ce joli carré peut servir comme entre-deux de rideaux ou peut encore orner le milieu d'une tétiere, coussin, etc.
No. 2. — Square in guipure on netting (Model by Mme Marchais, 46, rue de Clichy). After making even square, mount it on a brass wire frame or on a loom, in order to stretch it well, which facilitates the work and makes it regular. To embroider the net, take very shiny lace thread, then start making all the outlines with the darning point, then fill in all the patterns with the canvas point.
This pretty square can be used as a curtain insertion or can even adorn the middle of a headrest, cushion, etc.
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my size kink ass, who can barely fit my small size BD, just came hard as fuck trying to fit my wand vibe inside bc that is 😅 certainly a kink of mine
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