Showing papers by "Nankai University published in 1982"

Observation of Space Charges in the Photorefractive Region and Surface Electric Breakdown in LiNbO3-Fe

Abstract: The space chages formed in the process of photorefraction in LiNbO3 crystals is visualised by charged powder techniques. The results confirmed the existence of space charge carriers at the periphery of the illuminated region with negative charge carriers in the +z periphery and positive in the −z. The observed patterns on the surface of LiNbO3-Fe (0.05%) crystal illuminated with higher light intensities presented discharge-like features, namely traces of discharge in the medium at the crystal surface. The correlation between the kinetics curves of birefringence changeΔn(t) and the revealed surface patterns indicated that electric breakdown of the medium at the surfaces was responsible for the periodic reduction ofΔn(t).

A preliminary study on chinese dimorphopterus stal (hemiptera: lygaeidae: bli3sinae)

Abstract: In this study on the Chinese Blissine bugs of the genus Dimorphopterus, 11 species are recognized, of which 4 species are new to science and 3, viz D, lotus (Distant), D. lepidus Slater, Ashlock et Wileox, and D. sumatrensis Slater are new records to China. The new species are described as follows. All measurements arc in mm.Dimorphopterus nigripes ep. nov (fig. 4) Head and pronotum black and shining, pronotal posterior margin broadly testa-ceus ; antennae blackish brown ; scutellum black, pruinose ; basal half of clavus, apical half of corial veins and apical corial angles blackish brown, membrane opaque, yellowish, veins blackish brown ; propeuron and front acetabulum lacking any indications of pruinosity, meso- and meta- pleuron pruinose; posterior margin of metapleuron light yellowish brown ; scent gland auricles reddish brown ; legs blackish brown.Head length 0.44, width 0.68; antennal segments length: 0.13:0.28:0.26:0.53; pronotum trapezoidal, length 0.79, width 1.20, hairs decumbent, punctuation similar to D. spinola-e, but more denser in callar region ; seutellar length 0.35, width 0.66 ; claval commissure length 0.30, distance apex clavus-apex corium 0.68, distance apex corium-apex membrane 0.88; fore femora mutic, in male abruptly excavated distally (fig. 7) ; body length 3.0-3.8.Belonging to Slater's spinolae group and closely related to D. spinolae (Signoret), but a little more stout, hind margin of promotum and metapleuron light-colored, pronotal hairs decumbent, scutellum wider, claval commissure shorter, and legs darker, distal excavation of male fore femora more abrupt and deep.Holotype (?), allotype (?), paratypes (?): Shantung, (deposited in Nankai Univ).Dimorphopterus rectus sp. nov. (fig. 1)Brachypterus form: in general habitus close to D. spinolae (Signoret), but body smaller, rostrum reaching anterior margin of hind coxae; scutellum distinctly broad and short, distal excavation of male femora abrupt and deep, similar to that of D. pattipes, but without tubercles on posterior angle of the excavation; the pruinosity of propleuron and front acetabula also like that of D. pallipes ; brachypterous f orewings short, bluntly triangular, inner margins of clavus far apart. The opaque membrane and slender body form distinguishing this new species from the oriental D. rondoni, D. lepidus, and D. sumatrensis with longer rostrums.Head length 0.44, width 0.64; antennal segments length 0.13:0.26:0.19:0.44; pronotal length 0.66, width 0.90 ; scutellum length 0.22, width 0.42 ; body length 3.3.Holotype (?): Kiangsi. (deposited in Tientsin Nat. Hist. Mus).Dimorphopterus exigttas sp. nov. (fig. 3)Brachypterus form : Body small and slender ; head black, shining, antennae ochra-ceus, 4th segment blackish brown; pronotum black and shining, hind margin broadly dark brown ; scutellum brown, pruinose ; clavus and corium whitish yellow, corium apical margin and distal 2/5 blackish brown, bagis of clavus yellowish brown ; membrane opaque, white; ventral side of head and thorax (including acetabula) pruinose throughout; legs ochraceus; abdomen chocolate brown.Head length 0.34, width 0.53, antennal segments length 0.11:0.22:0.20:0.40; rostrum well attaining to mesocoxae; pronotum quadrate, punctures not coarse, a little sparse in callar region, hairs decumbent or semi-erect ; pronotal length 0.48, width 0.66; seutellar length 0.18, width 0.28 ; the brachypterus fore wing attaining to 4th or 5th abd. segment; fore femora mutic, apex indistinctly concaved in male (fig. 8); scent gland auricles as shown in fig. 10 ; body length 2.6 - 2.8.Holotype (?): Fukien; allotype (?): Kwangtung. (deposited in Nankai Univ.)Allied to D. spinolae (Signoret) and pallipes (Dist), but much smaller and slender, wing and antennae light-colored, the thoracic pruinosity differed. Dimorphopterus tenuicornis sp. nov. (fig. 2)Body elongate, slender and parallel-sided; head and pronotum shining black, anten-nal segments Ⅰ Ⅱ ochraceus, Ⅲ Ⅳ blackish brown; scutellum black, pruinose; basis and inner margin of clavus, apical 1/3 of corium and distal ha