Corrosion Behavior of X80 Pipe Steel under HVDC Interference in Sandy Soil

With the development of high voltage direct current (HVDC) systems, some pipelines have been badly interfered. The corrosion mechanism of pipelines has not been clearly clarified. In this work, laboratory experiments were designed to study the corrosion behavior of X80 steel under HVDC interference in sandy soil. The corrosion rates were related to the change in direct current (DC) density, which experienced three stages in the interference process. As soon as high DC interference voltage was applied to the working electrode, the current density increased sharply to a peak value in a few seconds. It then decreased rapidly to a steady value over dozens of seconds. Finally, it remained steady for the remaining time. With the measurement of local soil properties, the change in DC density was attributed to the local soil temperature increment, the water content decrement, and the substantial growth in the soil spread resistance. Moreover, the parameters contribute to the corrosion reaction during the interference process. The corrosion products were characterized at different times of interference via Raman spectroscopy. Lepidocrocite was produced under high DC density and then transformed to hematite under low DC density. Based on the above, the corrosion model during HVDC interference is proposed

Anodic Polarization Behavior of X80 Steel in Na₂SO₄ Solution under High Potential and Current Density Conditions

X80 steel has great risk of corrosion in high voltage direct current (HVDC) interference cases. In this study, the anodic polarization behavior of X80 steel under high potential and current density in Na2SO4 solution was investigated. The I × R drop was eliminated using current interrupt technique during the potentiodynamic measurement. Therefore, the real polarization curve was obtained. The corrosion behavior was investigated by galvanostatic polarization, scanning electron microscopy, and X-ray photoelectron spectroscopy. The results show a new form of passivation route. The steel dissolved actively below −0.388 VSCE, then became partly passivated from −0.388 to 1.448 VSCE, and fully passivated above 1.448 VSCE. The passive film was formed containing Fe2O3 and FeOOH, and resistant to SO42− ions. It not only blocked the direct dissolution of steel, but also facilitated oxygen evolution. The corrosion rates of steel samples decreased after the passivation

Two new species and a key to species of the genus Proscleropterus Korotyaev (Coleoptera: Curculionidae) from China

<i>Proscleropterus</i> Korotyaev, 2008 <p> <i>Proscleropterus</i> Korotyaev, 2008: 99.</p> <p> Type species <i>Proscleropterus davidiani</i> Korotyaev, 2008.</p> <p> Comments. The genus and its two close relatives <i>Scleropteroides</i> Colonnelli, 1979 and <i>Scleropterus</i> Schoenherr, 1825 share the structures of head with obvious median carina on vertex, convex eyes, antennal funicle 6-segmented, rostral channel extended up to apical margin of mesosternum, elytral intervals bearing sharp granules, dentate femora, mid and hind tibia mucronate in male.</p> <p> The rostrum is slender and not wider than fore femur in both <i>Scleropteroides</i> and <i>Proscleropterus</i>, whereas it is thick and wider than fore femur in <i>Scleropterus</i>. The rostral channel on meso- and metasternum is ill-defined and open on metasternum in <i>Proscleropterus</i>, whereas in <i>Scleropteroides</i> and <i>Scleropterus</i> it is deep, limited by keels, and closed.</p> <p> <i>Scleropteroides</i> has strongly prominent humeri, well-developed hind wings 1.9 times as long as elytra in <i>S. hypocrita</i> (Hustache), and its flying ability was observed in the field. <i>Scleropterus</i> has barely prominent humeri, elytra fused, and lacks of hind wings. <i>Proscleropterus</i> shows moderate humeri and reduced hind wing, not more than 1.8 times as long as elytra in <i>P. shennongjianus</i> Qin & Huang, <b>sp. nov.</b> (Fig. 4), and fused elytra, indicating that the hind wings of members of this genus are non-functional, and their status is somewhat intermediate between <i>Scleropteroides</i> and <i>Scleropterus</i>.</p> <p> Elytral intervals of <i>Proscleropterus</i> bear large sharp granules and strongly prominent tubercles, while those of <i>Scleropteroides</i> have small and evenly scattered granules, without prominent tubercles, and those of <i>Scleropterus</i> have large sharp granules and no tubercles in the type species <i>S. serratus</i> (Germar, 1824), or weak ones in <i>S. rubi</i> Korotyaev, 1980, <i>S. berezovskii</i> Korotyaev, 1992, and <i>S. sinensis</i> Korotyaev, 1992.</p> <p> Aedeagus body, apical projection excepted, is very similar in all the species of <i>Scleropteroides</i> (Huang <i>et al.</i>, 2014), whereas that of <i>Scleropterus</i> exhibits a little variation in the general appearance (Korotyaev, 2008). The aedeagus of <i>Proscleropterus davidiani</i> Korotyaev is long, narrow and widely rounded apically, while that of the two new species is short and broad and apically with blunt projection, being thus quite similar to that of <i>Scleropteroides</i>. Both new species have similar aedeagus body and other structures of genitalia.</p> <p> Recorded host plants of <i>Scleropteroides</i>, <i>Scleropterus</i> (Colonnelli, 2004; Huang <i>et al.</i>, 2014), and of <i>Proscleropterus shennongjianus</i> Qin & Huang, <b>sp. nov.</b> are in the genus <i>Rubus</i> (Rosaceae), genus particularly diverse in temperate regions of northern hemisphere, China comprised (Wu <i>et al</i>., 1994).</p>Published as part of <i>Mei Qin, Junhao Huang, Enzo Colonnelli, Runzhi Zhang & Hong Wu, 2016, Two new species and a key to species of the genus Proscleropterus Korotyaev (Coleoptera: Curculionidae) from China, pp. 173-185 in Zoological Systematics 41 (2)</i> on page 174, DOI: 10.11865/zs.201616, <a href="http://zenodo.org/record/270328">http://zenodo.org/record/270328</a&gt

Proscleropterus shennongjianus Qin & Huang, sp. nov.

<i>Proscleropterus shennongjianus</i> Qin & Huang, sp. nov. (Figs 5–8, 13–26, 41–43) <p>Types. Holotype. ♂ (ZAFU), " China: Hubei, Shennongjia-linqu, Muyu-zhen, Zhangbaohe, 106°72.26′N, 116°40.39′E, 21-V-2012, leg. J. Huang & L. Yang, CU00045". Paratypes. 5♂ 2♀, same data as holotype but "CU00046–00052" (ZAFU); 1♂ 2♀, same data as holotype but " 22-V-2012, leg. L. Yang, CU00053–00055" (ZAFU); 1♀, same data as holotype but " 22-V-2012, J. Huang, CU00056" (ZAFU).</p> <p> Description. Males (<i>n</i> =7). LB 2.30–2.69 mm (mean, 2.46 mm); LR 0.96–1.13 mm (mean, 1.03 mm); WP 0.76–0.91 mm (mean, 0.82 mm); LP 0.68–0.88 mm (mean, 0.75mm); WE 1.27–1.48 mm (mean, 1.36 mm); LE 1.37–1.59 mm (mean, 1.47 mm).</p> <p>Body dark brown; elytra more or less shining; eyes brown; antennae reddish-brown; legs from reddish-brown to dark brown. Habitus as shown in Figures 13–15.</p> <p>Vestiture. Body surface covered with more or less ochreous pollinosity in living specimens. Head (Figs 5–6) covered with brownish clavate scales, and sparse white or yellowish clavate scales behind eyes and on frons, being the median carina clothed with whitish or yellowish clavate scales at base; basal margin fringed with white ovate recumbent scales. Rostrum (Figs 5–6) clothed with white clavate scales on base and brown clavate scales on basal half; scales directed basally, gradually becoming slenderer towards apex, and replaced by hair-like scales on apical third. Prothorax (Figs 13, 15) mainly covered with clavate scales as those on head, with longitudinal stripe of white clavate and oval scales on median and lateral surface which form three well-defined narrow white or yellowish longitudinal stripes. Elytra (Figs 13–15) bearing brown clavate scales on each interval and white clavate scales along apical margin, whereas sparse slender linear scales directed apically are on striae. Legs (Fig. 14) densely covered with white and brown scales; femora and tibiae mostly covered with clavate semirecumbent scales, except semirecumbent hair-like scales along inner margin; corbel of each tibia fringed with brown setae. Underside generally covered with white from lanceolate to oval recumbent scales mingled with white and brown clavate scales; ventrites (Fig. 16) I and II bearing white lanceolate scales mingled with clavate scales; III and IV with a row of sparse white clavate scales; V bearing dense hair-like brown scales in median concavity and white lanceolate scales on each side. Pygidium (Fig. 17) covered with slender linear brown scales, and short apically pinnate scales on basal part.</p> <p>Head (Figs 5–6) coarsely reticulately punctured. Vertex with obvious median carina from base to apex; frons moderately deeply depressed, its apex almost equal in width to the base of rostrum and then strongly widened basally. Eyes medium-sized, moderately convex and triangularly rounded. Rostrum slender, 1.29–1.47 times as long as pronotum, 4.58–5.87 times as long as wide at apex, evenly curved; sides subparallel on basal half, then moderately widening near antennal insertion, and gradually so towards apex where rostrum is 1.15–1.29 times as wide as base. Dorsal surface of rostrum densely rugosely punctured except at apex, punctures forming ill-defined wrinkles; these punctures are medium-sized and slightly elongate from base up to between antennal insertion, then they become smaller, sparser, and shallower towards apex. Antennae inserted at 0.47 length of rostrum from apex; scape moderate in length, evidently clavate, round and fringed with 2 short setae at apex, funicle six-segmented; club lanceolate, finely pubescent except on basal part; scape 0.97 times as long as the funicle, length ratio of funicular segments I: II: III: IV: V: VI = 2.71: 1.79: 1.31: 1.14: 1.00: 1.02 and width ratio = 1.42: 1.00: 1.08: 1.09: 1.27: 1.45.</p> <p>Pronotum (Figs 13, 15) 1.03–1.17 times as wide as long, 0.47–0.57 times as long and 0.55–0.64 times as wide as elytra. Pronotum with two pairs of median tubercles along lateral sides which are subparallel on basal half, strongly convergent between the tubercles and then subparallel on apical half; median sulcus shallow on basal half; disc densely coarsely punctured, punctures of apical and basal parts smaller, apical margin weakly raised, moderately produced over head, with median incision. Base not margined, punctuation reaching basal edge and leaving no smooth line at base. Scutellum oval-shaped.</p> <p>Elytra (Figs 13–15) subcordate, 1.06–1.11 times as long as wide, 1.76–2.10 times as long and 1.55–1.79 times as wide as pronotum, with strongly prominent humeri and large sharp granulate tubercles on base of interval VIII; widest at basal fifth, evenly and gradually convergent apically. Striae relatively narrow but often bending around numerous large tubercles on intervals; punctures separated by a distance about twice their diameter. Intervals slightly shining, flat between tubercles. Interval I with a row of sparse granules on apical 3/4; interval II with 2–3 sparse granules on basal fifth, and with a weakly elongate tubercle composed of 5–6 merged granules on middle of one elytron, or with 2 feebly elongate tubercles composed of 2–3 merged granules on the other elytron; interval III with 3 weakly convex granules near base and two moderately large oblong or round tubercles composed of 2–3 merged granules basad and apicad of middle, followed by an additional convex granule and a row of sparse granules on apical part; interval IV narrow and just bearing a few sharp granules along the entire length; interval V with rather large short 5-capitate tubercle near the base, another small tubercle composed of 2 merged granules basad of middle, a sharp granule apicad of it and a round 5–7 capitate tubercles on apical fourth; interval VI with sculpture similar to that of IV; interval VII with a few large sharp granules scattered along its basal half, and a tubercle composed of 2–3 merged granules apicad of middle; interval VIII with large tubercles at base, then 2–3 granules basad and apicad of middle followed by sparse granules on apical part; interval IX with a weak tubercle composed of 3 merged granules on basal third, then with irregularly sparse granules from middle to apical fourth, and a much weak tubercle composed of 2 smaller granules on apical fourth; the rest of intervals with simple, small irregular granules.</p> <p>Legs (Figs 13–14) slender; femora slightly clavate, each armed with small tooth; tibiae not curved at apex; protibiae simple, lacking mucro at apex; meso- and metatibiae with moderate mucrones, mesotibial ones as long as tarsal claw, metatibial mucrones shorter than tarsal claw; tarsi moderate in length; claws with appendages as long as 4/5 of claw.</p> <p>Underside (Figs 3, 16). Prosternum coarsely and moderately punctured; mesoventrite with sparser punctures on disc and dense fine punctures on sides; metaventrite with medium-sized punctures and with slight median sulcus; lateral pieces of meso- and metaventrites with dense coarse medium-sized punctures. Procoxae and mesocoxae strongly inflated (Fig. 3). Rostral channel long, extending to the level of posterior margins of mesocoxal cavities. Ventrites (Fig. 16) with coarse and more or less dense punctures; ventrites III and IV with only one row of coarse and sparse punctures; ventrite V with subtriangular median concavity along basal margin; length ratio of ventrites I: II: III: IV: V = 3.55: 2.37: 1.06: 1.00: 2.38 and width ratio =1.40: 1.62: 1.26: 1.15: 1.00. Pygidium (Fig. 17) moderately transverse, about 1.14 times as wide as long, coarsely and moderately punctured and with fine median carina.</p> <p>Terminalia and genitalia. Penis (Figs 18–19) broad, relatively thick in lateral profile; sides weakly widening from base to apical 1/6, then strongly converging apically; apical projection (Fig. 20) blunt, rounded at apex. Endophallus (Fig. 18) with a pair of plate-like sclerites on apical part, and a pair of tubular structures on basal part. Spiculum gastrale (Fig. 22) robust, bent leftward and by far exceeding the length of aedeagal body or its apodeme. Tegmen (Fig. 21) with apodeme more or less stout, nearly as long as the diameter of the tegminal ring, more or less widening toward apex.</p> <p> Female (<i>n</i> =5). LB 2.52–2.86 mm (mean, 2.70 mm). LR 1.10–1.38 mm (mean, 1.23 mm). WP 0.82–0.96 mm (mean, 0.88 mm). LP 0.71–0.89 mm (mean, 0.80 mm). WE 1.30–1.59 mm (mean, 1.49 mm). LE 1.44–1.77 mm (mean, 1.63 mm).</p> <p>Rostrum (Figs 7–8) slightly slenderer, 1.56–1.67 times as long as pronotum, about 1.25 times as long as in male. Antennae inserted just behind the middle of the rostrum.</p> <p>Pronotum 1.07–1.16 times as wide as long.</p> <p>Elytra 0.99–1.14 times as long as wide.</p> <p>Tibiae simple, not mucronate.</p> <p>Ventrites I and II moderately inflated, sparsely punctured. Ventrite V with shallow median concavity. Pygidium smaller than that of male, 1.31 times wider than long.</p> <p>Terminalia and genitalia. Tergite VIII (Fig. 23) with pair of combs of dense, long setae along apical margin. Sternite VIII (Fig. 24) with a pair of patches of several minute setae near apex; arms slender and apically fused, about 0.5 times as long as apodeme, nearly half as long as coxite and stylus combined. Coxites (Fig. 25) robust, subdivided into two pieces, about 8.0 times as long as styli; styli apicolaterally inserted, moderate in length, nearly 2.0 times as long as wide. Spermatheca (Fig. 26) C-shaped, collum hardly convex; ramus indistinct, outline almost uniformly continuous; cornu slender, strongly curved and attenuate.</p> <p>Otherwise as in male.</p> <p>Etymology. The species is named after its type locality, Shennongjia Mountains, Hubei province, China.</p> <p>Distribution. China (Hubei; Fig. 44).</p> <p> Biological notes. Adults of this species were collected on flowering <i>Rubus eucalyptus</i> Focke (Rosaceae) (Figs 41–43).</p> <p> Remarks. The new species differs from <i>P. davidiani</i> in having pronotum with two pairs of sharp large median tubercules on lateral sides and then widening on basal half, elytra subcordate and evenly converging towards apex, while in <i>P. davidiani</i> pronotum bears only one pair of weak tubercules and is subparallel-sided, elytra are more elongate and subparall-sided on basal half. Moreover, <i>P. davidiani</i> has larger granules and different distribution of tubercles on elytral intervals.</p>Published as part of <i>Mei Qin, Junhao Huang, Enzo Colonnelli, Runzhi Zhang & Hong Wu, 2016, Two new species and a key to species of the genus Proscleropterus Korotyaev (Coleoptera: Curculionidae) from China, pp. 173-185 in Zoological Systematics 41 (2)</i> on pages 176-180, DOI: 10.11865/zs.201616, <a href="http://zenodo.org/record/270328">http://zenodo.org/record/270328</a&gt

Proscleropterus davidiani Korotyaev 2008

<i>Proscleropterus davidiani</i> Korotyaev, 2008 <p> <i>Proscleropterus davidiani</i> Korotyaev, 2008: 100.</p> (Figs 1–2) <p> Diagnosis. Although very similar in general appearance to the two new species here described, <i>P. davidiani</i> can be easily differentiated from both of them by its more elongate body, its relatively lenghtened subparallel-sided pronotum, and relatively long elytra subparallel-sided on basal 2/3, and bearing larger and sharper granules on elytral intervals.</p> <p>Materials examined. Paratypes. 1♂ 1♀, China, Sichuan, right bank of Lanhegou, River NW of Mt. Ubaoshan, E of Jimi, 3 000–3 200 m, 28–29-VI-2000, leg. Davidian G. E (ECC).</p> <p>Distribution. China (Sichuan; Fig. 44).</p> <p>Biological notes. Plant association unknown.</p>Published as part of <i>Mei Qin, Junhao Huang, Enzo Colonnelli, Runzhi Zhang & Hong Wu, 2016, Two new species and a key to species of the genus Proscleropterus Korotyaev (Coleoptera: Curculionidae) from China, pp. 173-185 in Zoological Systematics 41 (2)</i> on pages 175-176, DOI: 10.11865/zs.201616, <a href="http://zenodo.org/record/270328">http://zenodo.org/record/270328</a&gt

Characterization of the complete mitochondrial genome of Caryopemon giganteus Pic (Coleoptera: Chrysomelidae: Bruchinae)

We sequenced, assembled, and annotated the complete mitochondrial genome of the seed beetle Caryopemon giganteus, which represents the first report in the tribe Caryopemini from the subfamily Bruchinae of Chrysomelidae. The circular mitochondrial genome of the species contains 15,727 bases, 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, and a non-coding region. The GC content of the genome is 25.3%, which is higher than any other reported mitochondrial genomes within Bruchinae. The 16S ribosomal RNA gene and the 12S ribosomal RNA gene are 1284 and 835 bp in length, respectively. 12 PCGs started with the typical ATN codon, except for ND1 initiated with TTG. Five PCGs have the typical stop codon of TAA or TGA, while the remainder PCGs are terminated with incomplete stop codons (TA or T). The phylogenetic analysis based on a combination of 13 genes of the mitochondrial genomes of six species of Bruchinae and 23 species from other 10 subfamilies of Chrysomelidae recovered a generally well resolved and strongly supported tree topology, which shows that C. giganteus has the basalmost position in Bruchinae

<i>Chlorella emersonii</i> Inoculation Improves Pakchoi Yield and Nitrogen Use Efficiency Through Amending the Rhizosphere Microbial Community

An experiment of pakchoi after conventional fertilization was conducted with Chlorella emersonii inoculation. The yield, nitrogen use efficiency, and rhizosphere microbial community of pakchoi were investigated, and the relationship among them was also determined. The results showed that C. emersonii inoculation with half dose increased the fresh weight and nitrogen use efficiency of pakchoi by 6.5% and 28.1%, respectively. Rhizosphere microbial community structure after C. emersonii inoculation was distinctly affected, which reflected the higher bacterial alpha diversity and lower fungal alpha diversity, and had positive and negative correlations with pakchoi performance characteristics, respectively. The dominant phyla showed that C. emersonii inoculation significantly increased the abundance of Proteobacteria and decreased the abundance of Actinobacteria for bacteria, however, all fungal abundances also decreased. At a higher classification resolution, C. emersonii inoculation enriched the indigenous Sphingomonas and introduced the nonindigenous Pseudofulvimonas involved in the nitrogen cycle, which might be responsible for the improvement of pakchoi yield by enhancing nitrogen use efficiency. The higher bacterial alpha diversity with enriched Sphingomonas and Pseudofulvimonas might provide a driving force for the greater pakchoi yield and nitrogen use efficiency under the half dose of C. emersonii inoculation compared with the total dose. This study suggested that C. emersonii inoculation improved the yield and nitrogen use efficiency of pakchoi through the amendment of beneficial rhizosphere microflora, especially those related to the nitrogen cycle, and confirmed the positive effectiveness of conventional fertilization regimes together with C. emersonii inoculation on fertilization efficiency and agricultural production

Geometric morphometrics analysis of the hind wing of leaf beetles: proximal and distal parts are separate modules

The success of beetles is mainly attributed to the possibility to hide the hindwings under the sclerotised elytra. The acquisition of the transverse folding function of the hind wing is an important event in the evolutionary history of beetles. In this study, the morphological and functional variances in the hind wings of 94 leaf beetle species (Coleoptera: Chrysomelinae) is explored using geometric morphometrics based on 36 landmarks. Principal component analysis and Canonical variate analysis indicate that changes of apical area, anal area, and middle area are three useful phylogenetic features at a subtribe level of leaf beetles. Variances of the apical area are the most obvious, which strongly influence the entire venation variance. Partial least squares analysis indicates that the proximal and distal parts of hind wings are weakly associated. Modularity tests confirm that the proximal and distal compartments of hind wings are separate modules. It is deduced that for leaf beetles, or even other beetles, the hind wing possibly exhibits significant functional divergences that occurred during the evolution of transverse folding that resulted in the proximal and distal compartments of hind wings evolving into separate functional modules

How Was the Late Neogene Red Clay Formed in the Ordos Plateau (Northwest China)?

Eolian sediments are extensively distributed across the Earth’s surface, and their formation is intricately linked to climate change, tectonic activity, and topographic features. Consequently, the investigation of eolian sediments bears great geological significance. The northwest region of China is renowned for hosting the most extensive and thickest Late Miocene–Pliocene red clay deposits globally. Nonetheless, scholars have yet to reach a consensus regarding the precise formation processes of these red clays. The identification of the source region of the red clays is crucial for comprehending their formation mechanism. The correlation of zircon U-Pb age spectra is a frequently utilized method for determining the provenance of eolian sediments. In this study, we compared the previously published zircon U-Pb ages (n = 12,918) of the Late Miocene–Pliocene red clays in the Ordos Plateau with those from the potential provenance regions (n = 24,280). The analysis, supported by the tectonic and climatic background of the region, revealed that the Late Miocene–Pliocene red clay in the Ordos Plateau originates predominantly from the Yellow and Wei rivers, with a minor contribution from the weathering of bedrock in the western North China Craton. The transport of these detrital materials by the East Asian winter monsoon is impeded by the presence of the Qinling and Taihang Shan, resulting in their deposition on the flat surface of the Ordos Plateau. This development of red clay is consistent with the proximal accumulation model, illustrating how the hydrosphere, atmosphere, and lithosphere interacted to shape the red clay deposits during the Late Miocene and Pliocene periods in the Ordos Plateau