1,428,440 research outputs found
Scaptodrosophila zebromyia Peng, Lin & Chen, 2022, nom. nov.
No full textScaptodrosophila zebromyia nom. nov. Scaptodrosophila zebrina Liu & Chen, 2018, hom. of S. zebrina (Bezzi, 1928). Distribution. China (Yunnan).Published as part of Peng, Hongen, Lin, Yong & Chen, Hongwei, 2022, Morphological and molecular evidence of eight new species of the genus Scaptodrosophila Duda (Diptera, Drosophilidae) from China, pp. 169-194 in Zootaxa 5093 (2) on page 186, DOI: 10.11646/zootaxa.5093.2.3, http://zenodo.org/record/590508
Jingyi-Chen/cloud_parcel_mode: cloud parcel model
No full textThis is the first release of the cloud parcel model developed by Jingyi Chen. The development of this model was supported by Stony Brook University and Brookhaven National Laboratory in 2012-2014 (adiabatic version) and 2015-2017 (entrainment-mixing with entrained aerosols).
The publications associated with this code is below:
Chen, J., Y. Liu, M. Zhang, and Y. Peng (2016), New understanding and quantification of the regime dependence of aerosol-cloud interaction for studying aerosol indirect effects, Geophysical Research Letter, 43, 1780–1787, doi:10.1002/2016GL067683.
Chen, J., Y. Liu, M. Zhang, and Y. Peng (2018), Height dependency of aerosol-cloud interaction regimes, Journal of Geophysical Research: Atmospheres, doi: 10.1002/2017JD027431.
Chen, J., Y. Liu and M. Zhang (2020), Effects of Lateral Entrainment-Mixing with Entrained Aerosols on Cloud Microphysics, Geophysical Research Letter, doi: 10.1029/2020GL087667
Axinoscymnus hamulatus Peng et Chen 2022, sp. n.
No full textAxinoscymnus hamulatus Peng et Chen, sp. n. (Figs 9a–g) Diagnosis. This species is similar to A. puttarudriahi Kapur et Munshi in male genitalia but can be distinguished from the latter by the black head (Fig. 9c), the blackish brown pronotum and the black elytra without dark brown oval markings (Fig. 9a). In A. puttarudriahi, elytra are black with a single elongate oval dark brown spot on each elytron (Fig. 8a). Description. TL: 1.36–1.48 mm, TW: 0.91–0.97 mm, TH: 0.62–0.68 mm, TL/TW: 1.49–1.53, EL/EW: 1.15– 1.21, PL/PW: 0.48–0.55, HW/PW: 0.67–0.72, PW/EW: 0.72–0.73. Body elongate oval, moderately convex, dorsum with white pubescence (Figs 9a–c). Head black, antennae and mouthparts yellowish brown (Fig. 9c), tip of mandibles dark brown. Pronotum and scutellar shield blackish brown. Elytra black (Figs 9a–c). Prothoracic hypomeron and prosternum blackish brown. Mesoventrite, metaventrite, and elytral epipleurae black. Legs yellowish brown. Head with fine frontal punctures, slightly larger than eye facets, 0.5–1.5 diameters apart. Eye densely faceted, interocular distance 0.34 times of head width (Fig. 9c). Pronotal punctures slightly larger than those on frons, 0.5–2.0 diameters apart. Surface of elytra with punctures much larger than those on pronotum, separated by 1.0–2.0 diameters. Abdomen dark brown. Abdominal postcoxal lines complete and strongly recurved, nearly reaching posterior margin of ventrite 1 (Fig. 9d), area enclosed by the lines finely and sparsely punctate, irregularly distributed, broadly smooth along the lines; ventrite 1 with coarse punctures at middle, extremely sparse. Male genitalia. Penis short and slender, slightly broadened at base, apical 2/3 narrowing and apex blunt (Fig. 9e); tegmen with penis guide widest at base, slowly narrowing to apical 1/2, then slightly curved and abruptly tapering to apex in lateral view (Fig. 9f), slightly shorter than parameres; in inner view, penis guide subtriangular, widest at base, then gradually tapering to pointed apex (Fig. 9g); parameres stout and elongate oval with a few setae at apex in lateral view (Fig. 9f). Type material. Holotype: male, No. SCAU (E)17042, CHINA: Yunnan: Longmen, Shangyong, Mengla, Jinghong, 1. V. 2008. Wang XM et al. leg (SCAU). Paratype: Yunnan: 1♀, with same data as holotype (SCAU). Distribution. China (Yunnan). Etymology. The specific epithet is derived from the Latin adjective “ hamulatus ”, referring to its penis guide distinctly curved inwardly in lateral view.Published as part of Peng, Feng, Xie, Xiufeng, Peng, Zhengqiang, Wang, Xingmin & Chen, Xiaoshen, 2022, A taxonomic review of the genus Axinoscymnus Kamiya, with descriptions of three new species (Coleoptera, Coccinellidae), pp. 431-453 in Zootaxa 5154 (4) on pages 444-445, DOI: 10.11646/zootaxa.5154.4.2, http://zenodo.org/record/665115
Axinoscymnus pingxiangicus Peng et Chen 2022, sp. n.
No full textAxinoscymnus pingxiangicus Peng et Chen, sp. n. (Figs 1a–h, 13a–g) Diagnosis. This species is similar to A. nigripennis Kamiya in colour pattern but can be separated from the latter by slightly rounded body shape (Fig. 13a), the triangular penis guide in inner view (Fig. 13g) and ventrite 1 with fine punctures at middle (Fig. 13d). In A. nigripennis, it has an elongate oval body shape (Fig. 12a), the parallel sided penis guide in inner view (Fig. 12g) and ventrite 1 with coarse punctures at middle (Fig. 12d). Description. TL: 1.42–1.66 mm, TW: 1.06–1.29 mm, TH: 0.73–0.91 mm, TL/TW: 1.28–1.34, EL/EW: 1–1.03, PL/PW: 0.47–0.49, HW/PW: 0.66–0.70, PW/EW: 0.66–0.67. Body slightly oval, moderately convex, dorsum with white pubescence (Figs 13a–c). Head, antennae and mouthparts yellowish brown (Figs 1a, 13c), tip of mandibles dark brown. Pronotum and scutellar shield yellowish brown. Elytra black with narrowly apical margins yellowish brown (Figs 13a–b). Prothoracic hypomeron and prosternum yellowish brown. Mesoventrite and elytral epipleurae blackish brown. Metaventrite black. Legs yellowish brown. Head with fine frontal punctures, slightly larger than eye facets, 0.5–1.0 diameters apart. Eye densely faceted, interocular distance about 0.29 times of head width (Figs 1a, 13c). Pronotal punctures slightly larger than those on frons, 0.5–1.5 diameters apart. Surface of elytra with punctures much larger than those on pronotum, separated by 1.0–2.0 diameters. Abdominal postcoxal lines complete and moderately recurved, reaching 2/3 length of ventrite 1 (Fig. 13d), area enclosed by the lines finely and sparsely punctate, irregularly distributed, broadly smooth along the lines; ventrite 1 with fine and sparse punctures at middle, irregularly distributed. Male genitalia. Penis short and slender, slightly broadened at base, apex pointed (Fig. 13e); tegmen with penis guide in lateral view widest at base, gradually tapering to apex (Fig. 13f), in inner view subtriangular and stout (Fig. 13g), about 1/2 length of parameres; parameres stout and elongate oval with few setae at apex in lateral view (Fig. 13f). Type material. Holotype: male, No. SCAU (E)17041, CHINA: Guangxi: Daqingshan Mountains, Pingxiang, 2. VIII. 2005, Wang XM leg (SCAU). Paratypes: Guangxi: 1♀, with same data as holotype. 1♂ 1♀, Tongling Canyon, Huatong, 5. VIII. 2005, Wang XM leg. 1♂ 3♀, Pingxiang, Collecter unknown. Distribution. China (Guangxi). Etymology. The specific epithet is given after Pingxiang City, the type locality of this species.Published as part of Peng, Feng, Xie, Xiufeng, Peng, Zhengqiang, Wang, Xingmin & Chen, Xiaoshen, 2022, A taxonomic review of the genus Axinoscymnus Kamiya, with descriptions of three new species (Coleoptera, Coccinellidae), pp. 431-453 in Zootaxa 5154 (4) on pages 451-452, DOI: 10.11646/zootaxa.5154.4.2, http://zenodo.org/record/665115
Lobrathium chengzhifeii Lin, Chen & Peng, 2022, new species
No full textLobrathium chengzhifeii X.-B. Lin and Peng, new species (Figs 2B, 4, 7) Type material (2 ♂♂). Holotype ♂: “ China: Yunnan, Xishuangbanna, Menglong Town, Mengsong, 21°28’37’’N, 100°32’07’’E, 1570 m, 04.IV.2018, Peng, Shen & Cheng leg.” (SNUC); Paratypes: 1 ♂: same data as holotype (SNUC). Description. Measurements (in mm) and ratios: BL 6.45–7.23, FL 3.73–3.89, HL 0.88–0.92, HW 1.01–1.03, AnL 2.13–2.30, PL 1.13–1.14, PW 0.94–0.98, EL 1.16–1.20, AL 1.36–1.37, HL/HW 0.85–0.91, HW/PW 1.03–1.09, HL/PL 0.78–0.81, PL/PW 1.15–1.20, EL/PL 1.02–1.06. Habitus as in Fig. 2B. Body blackish brown, middle of elytra with yellowish spot not reaching lateral and posterior margins; legs brown with paler tarsi, antennae dark brown to light brown. Head weakly transverse, widest across eyes; posterior angles broadly rounded; punctation dense and coarse, sparser in median dorsal portion; interstices without microsculpture. Eyes large, more than half as long as distance from posterior margin of eye to neck in dorsal view. Pronotum lateral margins convex in dorsal view, punctation somewhat sparser than that of head, but with impunctate midline, interstices glossy. Elytral punctation coarse and dense, arranged in series; interstices without microsculpture. Hind wings apparently present. Abdomen punctation fine and dense; posterior margin of tergite VII with palisade fringe. Male. Sternites III–VI unmodified; sternite VII (Fig.4A) strongly transverse and with distinct median impression, this impression without pubescence, posterior margin broadly concave; sternite VIII (Fig. 4B) weakly transverse, with long and pronounced postero-median impression, this impression with moderately modified, stout and short black setae, posterior excision moderately broad and moderately deep, on either side of this excision with long dark setae; aedeagus as in Figs 4C, D, ventral process long, flattened, and apically convex in ventral view. Female. Unknown. Comparative notes. Regarding the morphology of the aedeagus, this species is similar to L. anatinum Li & Li, 2013, from which it is distinguished by somewhat smaller body size, lighter coloration of the body, the chaetotaxy of the male sternite VIII, and a stouter and more acute ventral process of aedeagus. For illustrations of L. anatinum see Li et al. (2013: figure 2). Etymology. The species is named after Zhi-Fei Cheng, who collected some of type specimens. Distribution and natural history. The type species were sifted near a pond in Xishuangbanna, Yunnan in April (Fig. 7).Published as part of Lin, Xiao-Bin, Chen, Xi & Peng, Zhong, 2022, A new species and additional records of Lobrathium Mulsant & Rey (Coleoptera Staphylinidae: Paederinae) from southern China, pp. 241-246 in Zootaxa 5133 (2) on page 244, DOI: 10.11646/zootaxa.5133.2.5, http://zenodo.org/record/652430
Synagelides tangi Liu & Chen & Xiao & Xu & Peng 2017, sp. nov.
No full textSynagelides tangi sp. nov. Figures 3−6, 9 Type material: Holotype: male (ASM-JGSU) from Shuikou, Xiajing village, Ciping Town, Jinggangshan County Level City, Jiangxi Province, China (26.551°N, 114.462°E, alt. 898 m), 7.XII.2013, K. Liu, Z. Chen & B. Xiao. Paratypes: 2 males and 1 female (ASM-JGSU), same data as holotype; China: Jiangxi Province, Jinggangshan County Level City: 1 male (ASM-JGSU), Xiajing village, Ciping Town (26.546°N, 114.467°E, alt. 849 m), 7.XII.2013, K. Liu, Z. Chen, B. Xiao; Maoping Town: 1 female and 3 males (ASM-JGSU) (Yuantou village, 26.626°N, 114.106°E, alt. 791 m), 5.IV.2014, K. Liu, Z. Chen, X. Huang, Z. Meng & Y. Tang; 4 females and 5 males (ASM-JGSU) (Yuantou village, 26.628°N, 114.106°E, alt. 906 m), 5.IV.2014, K. Liu, Z. Chen, X. Huang, Z. Meng & Y. Tang; 1 female (ASM-JGSU) (Huangyangjie, 26.623°N, 114.117°E, alt. 1055 m), 5.IV.2014, K. Liu, Z. Chen, X. Huang, Z. Meng & Y. Tang; 1 male (ASM-JGSU) (Yuantou village, 26.632°N, 114.106°E, alt. 1029 m), 5.IV.2014, K. Liu, Z. Chen, X. Huang, Z. Meng & Y. Tang; Ciping Town: 1 male (ASM-JGSU) (Dajing village, 26.570°N, 114.122°E, alt. 956 m), 27.VIII.2015, Z. Chen, C. Dong, J. Zhang, C. Wu, X. Chen, Q. Chen, N. Wang, B. Xiao, S. Wu, S. He, C. Xu, H. Wu, H. Xiao, Y. Peng, D. Wu & X. Liu. Etymology. The specific name is a patronym in honor of Doctor Guo Tang, who contributed with many papers on spider taxonomy in China. Diagnosis. Males of this species can be easily identified (Figs 3C −F, 5C −G, 6A −D) by the blunt tip of broad median apophysis, the presence of a hook-shaped tibial apophysis, a thumb-like cymbial apophysis ventrally and a long posterior cymbial apophysis dorsally. The female is different from any other congeneric species by its genital area (Figs 4C–D, 6E–F), with very small and long C-shaped sclerotized loops and clear bell-shaped hood. Description: Male (Figs 3, 5, 6A −D). Total length 3.29, CL 1.59, CW 1.03, AL 1.62, AW 0.85. EL 0.92, AERW 1.04, AMEW 0.65, PERW 1.05, PMEW 0.87. Carapace reddish-brown (Fig. 3A), with radial grooves. Eye field square, covered with short yellow hairs. Fovea round, hollowed. Chelicerae yellowish-brown (Fig. 3B), with typical dentition: 2 promarginal teeth and 1 large bifurcated retromarginal tooth (Fig. 5B). Endites yellowishbrown (Fig. 3B), with abundant hairs on anterior inner margin, slightly longer than wide. Labium oval (Fig. 3B), yellowish-brown, with a few strong setae on anterior margin. Sternum reddish-brown (Fig. 3B). Measurements of legs: I 3.16 [0.99, 0.74, 0.79, 0.35, 0.29]; II 2.21 [0.68, 0.32, 0.48, 0.43, 0.30]; III 2.32 [0.67, 0.30, 0.48, 0.55, 0.32]; IV 3.28 [0.98, 0.41, 0.79, 0.75, 0.35]. Leg formula: IV, I, III, II. Femur I width 0.32; femur II width 0.22. Leg spination: I: Tibia p v 0-3-0, r v 0-3-0; Metatarsus p v 1 -0-1, r v 1 -0-1. Abdomen oval (Figs 3A, B), dorsum dark yellowish-gray, with two pairs of patches on anterior part, an obvious transverse light band on the medial part, and six lighter herringbone strips on posterior part. Spinnerets yellowish-brown (Fig. 3B), with abundant brown hairs. Palp (Figs 3C −F, 5C −G, 6A −D) with a short, hook-shaped tibial apophysis and a thumb-like cymbial apophysis, a long posterior apophysis on dorsal cymbium, all of them appressed to cymbium. Spiral embolus short, extending along the margin of the broad median apophysis. Female (Figs 4, 6E–F). Total length 3.65, CL 1.73, CW 1.12, AL 1.79, AW 1.09. EL 0.99; AERW 1.14, AMEW 0.78, PERW 1.14, PMEW 1.02. Abdomen (Figs 4A, B), with lighter and slender herringbone strip. Measurements of legs: I 3.15 [0.98, 0.76, 0.81, 0.35, 0.25]; II 2.34 [0.78, 0.35, 0.48, 0.46, 0.27]; III 2.56 [0.77, 0.33, 0.56, 0.61, 0.29]; IV 3.64 [0.97, 0.49, 0.88, 0.87, 0.43]. Leg formula: IV, I, III, II. Femur I width 0.32; femur II width 0.24. Epigyne (Figs 4C–D, 6E–F) with bell-shaped hood and copulatory openings bilaterally located; copulatory ducts with short C-shaped sclerotized loops, distally slender with short glandular ducts; spermathecae elongated, fertilization ducts short. Distribution. Known only from Jiangxi Province, China (Fig. 9).Published as part of Liu, Keke, Chen, Zhiwu, Xiao, Yonghong, Xu, Xiang & Peng, Xianjin, 2017, Three new species of Synagelides Strand, 1906 from China (Araneae: Salticidae), pp. 291-300 in Zootaxa 4350 (2) on pages 294-297, DOI: 10.11646/zootaxa.4350.2.5, http://zenodo.org/record/105314
Vies parallèles et mouvementées de Peng Shuzhi et Chen Bilan
No full textYingxiang Cheng, Cadart Claude. Vies parallèles et mouvementées de Peng Shuzhi et Chen Bilan. In: Perspectives chinoises, n°46, 1998. pp. 37-43
Scaptodrosophila undulata Peng & Lin & Chen 2022, sp. nov.
No full textScaptodrosophila undulata sp. nov. (Figs 5A–C, 12) Diagnosis. This species resembles S. angustifolia sp. nov. in body colour patterns (Fig. 5C), but can be distinguished from it by surstylus curved inward in posterior view (Fig. 12A); hypandrium lacking a pair of paramedian hypandrial bristle (Fig. 12C, D). This species exhibits the closest genetic affinity to S. longiciliata in light of divergence in COI barcodes (Table 2). Description. Head (Fig. 5A): Eyes brownish red. Ocellar triangle dark brown to black. Frons brown to dark brown. Anterior reclinate orbital setae usually outside and close to proclinate orbital setae; posterior reclinate orbital seta larger than others. Pedicel and first flagellomere brown to dark brown. Facial carina brown to dark brown. Face brown to dark brown. Clypeus brown to dark brown. Palpus yellowish to yellowish brown. Vibrissa prominent; subvibrissal setae small. Gena and postgena narrow. Thorax (Fig. 5B, C): Mesonotum black brown to black. Acrostichal setulae in ca eight regular rows. Scutellum black brown to black. Pleura dark brown to dark. Abdomen (Fig. 5B, C): All tergites brown to dark brown. Male terminalia (Fig. 12A–D): Epandrium with ca. 6 epandrial bristles near posterior and ventral margins per side. Surstylus with 10 peg-like surstylar teeth caudal margins (Fig. 12A, B). Hypandrium lacking hypandrial hairs. Pregonite with 3 sensilla medially. Postgonite weak. Phallus lacking pubescence (Fig. 12C, D). Female terminalia (Fig. 12E): Oviscapt expanded subapically, apically elliptic. Oviscapt narrow with 16 peglike ovisensilla per side on ventral margins. Measurements. BL = 2.27 mm in holotype (mm in 2♂ and 3♀ paratypes: 2.20–2.74 in ♂, 2.14–2.47 in ♀), ThL = 0.93 mm (0.93–1.20 in ♂, 1.07–1.13 in ♀), WL = 2.33 mm (2.33–2.40 in ♂, 2.27–2.67 in ♀), WW = 0.87 mm (0.93– 0.93 in ♂, 0.73–0.93 in ♀), arb = 4/2 (4/2), avd = 0.86 (0.75–1.00), adf = 2.33 (1.75–2.00), flw = 2.00 (1.50–2.00), FW/HW = 0.22 (0.22–0.24), ch/o = 0.10 (0.06–0.13), prorb = 0.46 (0.31–0.56), rcorb = 0.38 (0.23– 0.45), vb = 0.38 (0.38–0.50), dcl = 0.30 (0.26–0.35), presctl = 0.35 (0.32–0.50), sctl = 1.18 (1.11–1.33), sterno = 0.60 (0.50–0.75), orbito = 0.50 (0.43–0.67), dcp = 0.40 (0.27–0.36), sctlp = 1.00 (1.00–1.20), C = 1.56 (1.40–1.77), 4c = 1.50 (1.35–1.67), 4v = 2.50 (2.12–2.67), 5x = 2.80 (2.00–3.00), ac = 3.86 (3.57–3.75), M = 0.78(0.59–0.95), C3F = 0.67 (0.60–0.71). Materials examined. Holotype ♂, (SCAU, No. 125163), CHINA: Dupangling, Daoxian, Hunan, 25°48'N, 111°35'E, alt. 477m, 29.viii.2020, HE Peng. Paratypes: CHINA: 2♂, 3♀ (SCAU, Nos. 125164, 125169–125172), same data as holotype; 1♀, (SCAU, No. 125165), Guposhan, Hezhou, Guangxi, 24°29'N, 111°34'E, alt. 790m, 29.vii.2017, HW Chen; 3♂, 1♀ (SCAU, Nos. 125166–67, 125173–74) Mulun, Huanjiang, Guangxi, 24°83'N, 108°26'E, alt. 749m, 16.ix.2015, HW Chen. Distribution. China (Hunan, Guangxi). Etymology. Etymology. From the Latin word: undulatus, referring to the surstylus curved inward.Published as part of Peng, Hongen, Lin, Yong & Chen, Hongwei, 2022, Morphological and molecular evidence of eight new species of the genus Scaptodrosophila Duda (Diptera, Drosophilidae) from China, pp. 169-194 in Zootaxa 5093 (2) on pages 181-182, DOI: 10.11646/zootaxa.5093.2.3, http://zenodo.org/record/590508
Scaptodrosophila apunctata Peng & Lin & Chen 2022, sp. nov.
No full textScaptodrosophila apunctata sp. nov. (Figs 2D–F, 7) Diagnosis. This species differs from the other Chinese species in the coracina species group in the pattern on the abdomen tergites and male terminalia, but can be distinguished from them by hypandrium fused to pregonite apically, tubular-shaped on inner surfaces; phallapodeme (aedeagal apodeme in McAlpine 1981) recurved (Fig. 7C, D); tergites lacking black band (Fig. 2E, F). This species exhibits the closest genetic affinity to S. ventriobscurata in light of divergence in COI barcodes (Table 2). Description. Head (Fig. 2D): Frons brown. Pedicel hazel. First flagellomere yellowish brown. Facial carina yellowish brown, long, 1/2 the length of face. Thorax (Fig. 2E, F): Mesonotum yellow. Pleura yellow. Abdomen (Fig. 2E, F): Tergites yellow. Male terminalia (Fig. 7): Epandrium with ca. 8 epandrial bristles near posterior and ventral margins per side. Surstylus with 9 peg-like surstylar teeth on caudal margins (Fig. 7A, B). Hypandrium with a pair of paramedian hypandrial bristle. Pregonite with 5 sensilla medially. Postgonite roundly expanded, with pubescence apically. Phallus lacking pubescence (Fig. 7C, D). Measurements. BL = 3.45 mm in holotype (mm in 4♂ paratypes: 2.98–3.29), ThL = 1.29 mm (1.07–1.33), WL = 3.02 mm (2.53–3.07), WW = 1.29 mm (0.98–1.29), arb = 3/2 (3/2), avd = 0.92 (0.67–0.92), adf = 2.60 (1.67–2.60), flw = 2.20 (1.83–2.20), FW/HW = 0.44 (0.40–0.47), ch/o = 0.23 (0.20–0.25), prorb = 0.71 (0.57–0.86), rcorb = 0.36 (0.36–0.39), vb = 0.70 (0.25–0.63), dcl = 0.50 (0.38–0.47), presctl = 0.69 (0.55–0.61), sctl = 1.03 (0.89–1.07), sterno = 0.83 (0.50–0.74), orbito = 0.44 (0.33–0.53), dcp = 0.24 (0.20–0.22), sctlp = 0.90 (0.92–1.42), C = 2.50 (2.52–2.93), 4c = 1.00 (0.90–1.00), 4v = 2.22 (2.06–2.16), 5x = 1.13 (0.71–1.13), ac = 1.80 (1.80–2.27), M = 0.20 (0.29–0.50), C3F = 0.72 (0.77–0.81). Materials examined. Holotype ♂ (SCAU, No. 125106), CHINA: Moli Forest Park, Ruili, Yunnan, 24°07'N, 97°58'E, alt. 922m, 23.iv.2018, HW Chen. Paratypes: CHINA: 4♂ (SCAU, Nos. 125103–125105, 125107), Moli Forest Park, Ruili, Yunnan, 24°07'N, 97°58'E, alt. 922m, 23.iv.2018, HW Chen, L Gong, Y Lin. Distribution. China (Yunnan). Etymology. A combination of the Latin words “ absent ” + “ punctatus ”, referring to the tergites lacking bands.Published as part of Peng, Hongen, Lin, Yong & Chen, Hongwei, 2022, Morphological and molecular evidence of eight new species of the genus Scaptodrosophila Duda (Diptera, Drosophilidae) from China, pp. 169-194 in Zootaxa 5093 (2) on pages 176-177, DOI: 10.11646/zootaxa.5093.2.3, http://zenodo.org/record/590508
Identification and attenuation of slat noise
Full text linkIn the case of civil transport aircraft, engines were the dominant noise source until the advent of the high-bypass ratio engines in the early 1970s. Since then, airframe noise has become more important, particularly during the approach-to-landing stage of aircraft operations. The main components of airframe noise are the flap side edge, leading edge slat, and the landing gear. Experiments in both the wind tunnel and via fly-over measurements have shown that the slat noise is a major contributor to the overall airframe noise during the landing approach for a commercial aircraft.To achieve the goal of reducing slat noise significantly without adversely affecting the aerodynamic performance of the wing, it is obligatory to improve the understanding of the mechanism of slat noise generation. Experiments and numerical simulations were performed to investigate the phenomena of slat noise. It was found that the slat broadband noise generation is governed by two kinds of mechanism. At a low angle of attack of the wing, the typical circulation region is not formed in the slat cove and the slat noise level is low. As the angle of attack increases to a certain value, vortical structures are intermittently generated due to flow interaction occurring between the shear layer originating from the slat cusp and the flow convected from the stagnation line on the main element. Intense slat noise is produced as the vortical structures approach the slat cove surface. With the angle of attack increasing further, the slat noise becomes weak again. The interaction effect tends to become weaker as the shear layer deviates away from the surface of the main element.Two approaches with the aim of attenuating the slat noise were experimentally and numerically studied. The first approach was to reduce the slat noise using air blown on the suction surface of the slat near its trailing edge. A numerical simulation showed that the slat noise levels over most of the frequencies, especially above a St number of 7, were obviously attenuated. In the second approach, a strip mounted on the pressure surface of the main element model was experimentally proven to be an effective method for reducing the broadband slat noise at an angle of attack of 8 degrees and a freestream velocity of 25 m/s. The position and height of the strip also influenced the level of the reduction.Several tonal noise components appear in the slat noise spectrum at an angle of attack of 4 degrees and a freestream velocity of 25 m/s. The dominant tone is associated with the vortex shedding off the slat cusp through the Kelvin-Helmholtz instability. This tone was successfully suppressed using a plasma actuator employing an open-loop control. A maximum reduction of 11 dB was achieved at a St number of approximately 19.7. A quasi-static feedback control system was also developed, wherein a controller is responsible for calculating the control inputs in terms of feedback signals. The experimental results show that the controller can work effectively to suppress the slat noise
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