Abstract: This H section includes, as a chemical composition, C, Si, Mn, Nb, V, Ti, and N; in which the H section includes, as a metallographic structure, ferrite of 60 area % to less than 100 area %, an average grain size of this ferrite is 1 ?m to 30 ?m, a thickness of a flange is 20 mm to 140 mm, tensile yield stress is 385 MPa to 530 MPa, and Charpy absorbed energy at ?20° C. is 100 J or more.

Abstract: An electrochromic device of wholly solid type comprising a transparent substrate and a transparent electroconductive film formed on the substrate, and having an oxidation color forming oxide, a cation conductive layer as an electrolyte, a reduction color forming oxide and a transparent electroconductive film, formed sequentially on said transparent electroconductive film formed on the substrate, wherein:(1) the oxidation color forming oxide is a p-type semiconductor of nickel oxide or cobalt oxide,(2) the cation conductive layer has OH groups showing a peak at about 3,300 (1/cm) in its infrared reflectance spectrum and is made of proton conductive SbO.sub.c wherein 1.3.ltoreq.c.ltoreq.2.7, or at least one lithium conductive lithium-containing oxide of LiO.sub.d MO.sub.e wherein 0.01.ltoreq.d.ltoreq.1.0, 1.3.ltoreq.e.ltoreq.2.

Abstract: A counterelectrode for a smart window contains a transparent electrically conductive substrate and a plurality of electrically conductive dots arrayed on the transparent electrically conductive substrate. Each of the electrically conductive dots contains fine particles having capacitance of not less than 1 farad/g or fine particles capable of storing electrical charge of not less than 1 coulomb/g. A smart window contains the aforementioned counterelectrode.