384 research outputs found
Kinetic and mechanism of the reduction of NO by n-octane over Pt/Al2O3 under lean burn conditions
No full textThe effect of temperature, contact time, and reactant concentration on the reduction of NO by n-C8H18 over Pt/Al2O3 under oxidising conditions was investigated. The oxidation of n-C8H18 appears to be delicately balanced between two kinetic regimes. At low [C8H18]/[O2] the coverage of oxygen on the Pt surface is high, while that of carbonaceous species is negligible, resulting in hydrocarbon oxidation being inhibited by oxygen and in the oxidation of NO to NO2. At higher [C8H18]/[O2] the surface is saturated with carbonaceous species, while the coverage of oxygen is negligible, resulting in hydrocarbon oxidation being zero order in hydrocarbon concentration and in no NO2 formation being observed. The state of the Pt surface affects the mechanism of NOx reduction. Thus, NOx reduction via dissociation of NO on the Pt surface is favoured by a high coverage of carbonaceous species, while a high coverage of oxygen favours NOx reduction by reaction between n-C8H18-derived species and spilt-over NO2 on the Al2O3 support and/or metal-support interface. Separate kinetic models capable of fitting the data in these two regions have been developed
Cladarisis nouvianae Watling, 2015, new species
No full textCladarisis nouvianae new species Figures 1–7 Material examined. Holotype: Collected off Rum Cay, Bahama Islands, 23 ° 38.0756 'N, 74 ° 57.2196 'W, depth 1117 m, 24 March 2009, specimen RUM 107 - 2, YPM IZ 0 70870. Other material: Off Cat Island, Bahama Islands, 24 °08.9927'N, 75 ° 12.0680 'W, depth 1243 m, 21 March 2009, specimen CAT 207 - 1 (most of the specimen deteriorated during storage, after sclerite examination and genetic analysis; small fragments exist in the lab of S.C. France at the University of Louisiana at Lafayette, USA). Diagnosis. With the characters of the genus. Description of Holotype. The colony is long and slender, sparsely branched, with branches emanating from nodes. The holdfast is very small, not much larger than the diameter of the axis (Fig. 1 A). From the holdfast to the first branch point is about 10 cm, subsequent branches are spaced about 9 to 14 cm apart, with one interbranch distance of 4.5 cm. The two main branches carry two or three subsequent branches, one of which is branched twice more, resulting in two third-order branches that are approximately 18 cm long. Total colony length is about 75 cm (as determined by measurements made on the in situ image in Fig. 1 A). Axial internodes are solid, except for those newly forming at the ends of the branches. The internode hollow center appears to be secondarily calcified (Fig. 2 C). Internodes (Fig. 2 A, B) range in length from 3.5 to 14.9 mm (mean= 9.76 mm, std. dev.= 2.36, n= 49), and in width from 0.33 to 0.93 mm (mean= 0.67 mm, std. dev.= 0.21, n= 12). Nodes are very short, about 1 mm in length and do not seem to be very heavily calcified resulting in a very flexible colony whose branch tips are often curved (e.g., Fig. 1 B, 2 B). Polyps are small, less than 3 mm tall when contracted, and are arranged in two irregular rows along the branches, often in alternate fashion (Fig. 2 A,B). Interpolyp distances in each row range from 5 to 18 mm, but are most frequently about 10 mm. No polyps are present on the distal-most 3 cm of the branches and polyps and tissue appears to be absent along part of the axis from the holdfast to the first branch-point. Because of the relative shortness of the internodes, each internode supports only one or two polyps; occasionally a polyp is located on a node. Polyps are short cylinders, being as wide as tall (Fig. 3 A-D). When contracted the tentacles are not visible and the top of the polyp is covered with a logjam of rod-shaped sclerites (Fig. 3 D). The outside of the polyp is festooned with curved rods that are loosely organized. The longer sclerites originate at the base of the polyp, often extending the width of the skeletal axis, and are oriented diagonally. The shorter sclerites are mostly located higher on the polyp and can be oriented either horizontally or longitudinally. None of the sclerites appear to be aligned directly with the mesenterial insertions on the polyp body wall (Fig. 3 B). All sclerites on the polyp body are robust rods with blunt or rounded tips (Fig. 4). Each is ornamented with small regularly spaced tubercles (Fig. 2 D, E). Most of the rods are curved or have irregular outlines. Only those at the base of the tentacles are more or less straight (Fig. 5 D). Rods are oriented longitudinally along the aboral side of the tentacles, becoming progressively smaller toward the tentacle tip. Flat rods (Fig. 5 C) are common in the pinnules and along the oral surface of the tentacles. Polyp body sclerites range in length from 1.0 to 2.5 mm, the rods along the aboral side of the tentacles are 0.4 to 0.9 mm long, and tentacle flat rods are 0.06 to 0.15 mm (Fig. 6). The pharyngeal sclerites are 0.07 to 0.14 mm in length. The tentacles contract completely into the oral cavity of the polyp (Fig. 3 D, 7 A). The “mouth” is funnelshaped, demarcated from the pharynx by a flat ring (R, Fig 7 A). The pharynx (as determined by the presence of pharyngeal sclerites) continues the structure ventrally, terminating in a hypopharynx (H, Fig 7 A, 7 C) uniting the eight septa. The sclerites of the pharynx region consist of two distinct types, those that are flat rods with tooth-like protuberances (Fig. 5 B) being found at the junction with the oral funnel, while the more typical short and wide toothed rods (Fig. 5 A, 7 D) occupy the lower part of the pharynx. Variation. The only other specimen collected, CAT 207 - 1, was about 30 cm in length and branched twice. The polyps of the latter specimen were examined in detail and differed from those of the holotype only in having slightly smaller sclerites on the polyp body. The largest sclerites were 2.4 mm in length whereas on the larger holotype the largest body sclerites are about 2.5 mm in length (Fig. 6). But the smaller CAT 207 - 1 had a much larger array of smaller rods on the polyp body and the rods in the tentacles were much smaller than on the holotype. Etymology. This species is named in honor of Claire Nouvian, founder of the organization Bloom Association, in recognition of her tireless efforts working to reduce the destruction of deep-sea habitats by bottom trawls. Remarks. Within the Keratoisidinae, the genera Lepidisis, Jasonisis, Acanella, and Isidella were known to branch at the nodes if they branched at all (France 2007, Alderslade and McFadden 2012). Cladarisis branches at the nodes once the colony reaches sufficient size to begin branching. Among this group, the pattern of branching of Cladarisis is most similar to that seen in Isidella (sparse and lateral, not in whorls), and in fact, the specimens collected were provisionally assigned to that genus as samples were sorted on board the ship. The genus Isidella currently comprises the species I. elongata Esper, 1788 (type species), I. lofotensis Sars, 1868, I. trichotoma Bayer, 1990, I. longiflora (Verrill, 1883), and I. tentaculum Etnoyer, 2008. Only the first three are likely to remain in the genus. Isidella longiflora was originally described and placed in the genus Lepidisis by Verrill, but since that genus came to be thought of as unbranched, Grasshoff (1986; Grasshoff and Zibrowius 1983) moved longiflora to Isidella on the basis of dichotomous branching from the nodes. The exact placement of this species remains to be determined since the existing museum material is not in very good condition. Further, Verrill (1883) noted that branches arising at the nodes could arise singly, or two at a time. In a manuscript that was unfortunately not published before his death, Verrill suggested that L. longiflora should be moved to a new genus “ Acanellides ” (this manuscript is in the collection of the Yale Peabody Museum and photocopies of the pages can be obtained from this author). Isidella tentaculum differs from all the others in having sclerites in the form of rods, the mesenterially placed sclerites are rods rather than needles, and the branches, while originating at the nodes form more of a candelabra shape. In addition, the axis internodes are thick and heavy, rather than thin and moderately delicate. Unpublished genetic sequence data suggests that I. tentaculum belongs to a clade different from that in which the other three Isidella species (including the type) reside (Scott C. France, personal communication). Thus, for this discussion, the genus Isidella will be considered to consist only of the first three species noted above. The species Isidella elongata, I. lofotensis, and I. trichotoma have moderately long to very long, thin hollow internodes, polyps armed with sclerites predominantly in the form of needles, with larger needles in groups of 2-3 placed at the mesenterial insertions on the body wall (Bayer 1990) and usually projecting between the tentacle bases. Branching at the nodes has been termed dichotomous (Bayer 1990), but should be lateral according to Alderslade (1998), and sparse. The tentacles, when contracted, fold over the mouth but remain exposed. Isidella lofotensis needs redescription (in preparation); however, colonies recently studied in the collection of the Tromsø Museum are bushy, branching at the nodes in all planes, and the sclerites arranged along the mesenterial insertions are large pointed rods rather than thin needles. A very small colony collected in 1872 at the type locality by G.O. Sars, from the collection of the Copenhagen Museum, has a similar arrangement of polyp body sclerites, but all are needles rather than rods (inviting the supposition that as the colony grows and ages the needles either become thicker or are replaced). Both colonies have solid internodes. The tentacles contract but stay exposed. The genus Cladarisis resembles these three species of Isidella in the form of the colony, the long and thin branches, branching sparse and lateral, and with branches originating at the nodes. Cladarisis differs, however, in several ways. The internodes are generally shorter (mean length, 9 mm). Measurements made on photos of specimens of I. elongata and pieces of a specimen of I. lofotensis, show that internode length in those two species range from 13 to 17 mm and 9 to 15 mm, respectively. Internode lengths in I. trichotoma reach 85 mm (Bayer 1990). The polyp body of Cladarisis possesses sclerites that are exclusively rods, and the sclerites are organized haphazardly such that none are aligned with the mesenteries. Indeed, the rods are arranged almost randomly along the outside of the polyp, with some on the distal part of the polyp oblique to horizontal, and with longitudinally oriented smaller rods only along the aboral surface of the tentacles. The pharyngeal sclerites of Cladarisis also differ significantly from those of I. trichotoma (details for the other two species are missing). In the latter, the sclerites are elongate, slightly toothed rods, verging on being flat rods, whereas in Cladarisis one group of pharyngeal sclerites are short, wide, and thick, with protuberances on all sides.Published as part of Watling, Les, 2015, A new genus of bamboo coral (Octocorallia: Isididae) from the Bahamas, pp. 239-249 in Zootaxa 3918 (2) on pages 240-244, DOI: 10.11646/zootaxa.3918.2.5, http://zenodo.org/record/23807
Council cottages and community in inter-war Britain: a study of class, culture,politics and place.
No full textPhDThis thesis makes a contribution to the debates surrounding the idea of community
on the cottage council estates of inter-war Britain. It questions the conventional
wisdom that community was lacking upon these estates. Recognising the
problematic nature of the notion of community, this thesis overcomes the confusion
inherent in the term when it is used to describe social structures by viewing
community instead as a structure of meaning, as a discursive rather than material
reality. This guides my examination of community on the estates. Rather than
there being no community, it is argued that there were at least three different
discourses of community, and what is important is the relationships between them.
Chapter One discusses the contexts in which these estates were built, and then sets
out the ways in which community is understood in this thesis. Chapter Two
explains the methodology that was used, a combination of archival and oral histoiy.
In Chapter Three Roehampton and Watling - the two estates this research focuses
upon - are described in order to provide the contextual setting for my interpretation
of the discourses of community that were present there. Chapter Four is concerned
with community from the viewpoint of the residents who lived on the estates.
Chapter Five considers discourses of community from the point of view of the
tenants' and residents' associations that developed upon Roehampton and Watling.
Chapter Six explores the discourse of community that was promoted on the estates
by the Community Association movement.
Overall the thesis argues that the discourses of community on inter-war
housing estates have to be understood in terms of the occupational structures,
cultures and politics of these estates
Enhanced velocity overshoot and transconductance in Si/Si(0.64)Ge(0.36)/Si pMOSFETs - predictions for deep submicron devices
No full textNo abstract avaliable
Magelona paulolanai Magalhães & Bailey-Brock & Watling 2018, sp. nov.
No full textMagelona paulolanai sp. nov. Figures 2 (F‒H) and 5 Material examined. Holotype: Hawaii, Oahu, Mamala Bay, Sand Island outfall, Sta. B6R5, 21°17'04.7" N, 157°53'25.3" W, Aug/1992, 39 m (USNM 1494159). Paratypes: Same locality, Sta. B6R5, 21°17'04.7" N, 157°53'25.3" W, Aug/1992, 39 m (1 af, USNM 1494160); Sta. ZR2, 21°16'53.4" N, 157°54'21" W, Aug/1992, 40 m (1 af, BPBM-R 3872); B4R2, 21°17'01.4" N, 157°54'23.8" W, Aug/1991, 30 m (1 af, USNM 1494161); Sta. B1R3, 21°17'30.2" N, 157°55'44" W, Aug/1990, 33 m (1 af, BPBM-R 3873). Additional material examined: Mariana Islands, Guam, Northern District outfall, 13°29'14" N, 144°44'54" E, Jan/2007, 40‒ 52 m, Sta. N1R1 (1 af); Sta. N2R2 (2 af); Agana outfall, 13°33'08" N, 144°48'25" E, Jan/2007, 65‒ 100 m Sta. A1R2 (1 af), Sta. A1R3 (1af); A3R2 (1 af). Diagnosis. Prostomium longer than wide, with rudimentary prostomial horns. Notopodia of chaetigers 1‒8 with elongate foliaceous postchaetal lamellae with smooth upper edges. Superior processes present from chaetigers 1‒8, more elongate in the posterior thorax. Chaetiger 9 with only simple bilimbate capillaries. Abdominal hooded hooks tridentate. Posterior abdominal lateral pouches (C configuration) present from chaetiger 36 of holotype, paired and absent on last 7 chaetigers. Description. Holotype: complete specimen, both palps attached; prostomium 0.40 mm long, 0.37 mm wide; thorax 2.31 mm long (including prostomium), 0.31 mm wide; abdomen 0.27 mm wide; total length 15.66 mm for 67 chaetigers. Paratypes: all incomplete, (three with palps attached) measured; prostomium 0.34‒0.66 mm long, 0.33‒0.59 mm wide; thorax 2.57‒4.04 mm long (including prostomium), 0.35‒0.38 mm wide; abdomen 0.35‒0.46 mm wide; total length 5.91‒11.6 mm for 23‒54 chaetigers. Prostomium slightly longer than wide (L:W ratio 1.03‒1.12), rounded triangular; anterior margin smooth rounded, with rudimentary prostomial horns (Figs 2F; 5A, F). Two pairs of prominent longitudinal dorsal ridges, thin; outer pair, reaching further basally and approaching achaetous segment; inner pair diverging half way toward prostomial tip and posteriorly towards prostomial base, with slight medial gap (Fig. 5A, F); prostomium with lateral round markings on either sides of ridges. Burrowing organ partially everted in two paratypes, oval and with longitudinal ridges. Palps arising ventro-laterally from base of prostomium and extending to chaetiger 15 (Fig. 5A); palps measuring 6.79 mm long in holotype and ranging from 2.54‒4.97 mm long in paratypes; non‒papillated region very short, extending to chaetigers one or two (Fig. 5A). Papillae short proximally (Fig. 5B) but long for majority of length, elongate (Fig. 5C, D); proximally and distally with two rows of papillae and medially with four rows (Fig. 5B‒D). Achaetous segment twice as long as chaetiger one (Fig. 5A). Thoracic segments slightly longer than wide; chaetigers 1‒8 similar; parapodia biramous; notopodia with low prechaetal lamellae confluent with foliaceous postchaetal lamellae of similar size throughout thorax and becoming slightly broader on chaetiger 8 (Fig. 5H‒K); notopodial lamellae distally smooth. Prechaetal superior processes present (DML), digitiform on chaetiger one (Fig. 5G) and elongate on subsequent thoracic chaetigers (Fig. 5I, J). Neuropodial pre- and postchaetal lamellae as low ridges; ventral lobes (VNL) lobes elongate, as long as notopodial lamellae from chaetigers 1‒7 (Fig. 5H‒J). Chaetiger nine shorter and slightly constricted (Fig. 5K): notopodial prechaetal lamellae low, rounded, postchaetal lamellae triangular and slightly shorter than preceding thoracic chaetigers; superior processes (DML) absent. Neuropodia of chaetiger nine with digitiform prechaetal lobes and triangular postchaetal lamellae. Chaetae of thoracic chaetigers 1‒9 simple bilimbate capillaries (Fig. 5E); number of capillaries similar throughout thorax, 8‒10 per rami. Abdominal segments longer than thoracic ones; DML and VML present, digitiform. Abdominal parapodia with foliaceous lateral lamellae, basally constricted, well-separated; low postchaetal extension of lateral lamellae behind chaetal rows in anterior abdomen (Fig. 5L). Abdominal chaetae tridentate hooded hooks of similar size throughout; two same-sized teeth above main fang (Fig. 5G); a pair of internal arcuate chaetae present sensu Fiege et al. (2000) in abdominal chaetigers. Hooks in two groups, outer group with usually an additional hook than inner group, hooks of similar size, main fangs vis–à–vis (Fig. 5L). Anterior abdominal segments with 4‒5 hooks per ramus. Anterior abdominal lateral pouches (Σ configuration) absent and posterior abdominal lateral pouches (C configuration) present from chaetiger 36 of holotype, paired and absent on last 7 chaetigers; all specimens with paired interparapodial glandular regions on anterior abdominal segments. Pygidium with a pair of short ventral cirri (Fig. 5M). All preserved specimens lacking pigmentation, pale yellow. Methyl Green Staining. Anterior end not distinctly stained. Dark green speckles present as transverse bands on anterior end of every segment in thorax and abdomen (Fig. 2G). Ventral region of chaetiger four with dense green speckles (Fig. 2H). Abdominal region staining intensely as interparapodial patches (Fig. 2G, H). Remarks. Magelona paulolanai sp. nov. is most similar to M. pitelkai Hartman, 1944, M. berkeleyi Jones, 1971 and M. dakini Jones, 1978 by the shape of the prostomium having weakly-developed (rudimentary) prostomial horns, shape of parapodial lamellae from chaetigers 1‒8 and presence of tridentate abdominal hooks. It differs from M. pitelkai by the absence of modified chaetae on chaetiger nine. Magelona berkeleyi differs from M. paulolanai sp. nov. in the shape of the prostomium, prostomial longitudinal ridges and methyl green staining pattern. The prostomium of M. berkeleyi is wider than long with short but distinct frontal horns whereas M. paulolanai sp. nov. has a prostomium that is longer than wide and the prostomial horns that are not distinctly separated from prostomium; the inner pair of prostomial dorsal ridges in M. berkeleyi is completely separated and short while in M. paulolanai sp. nov. only a slim gap is present. The methyl green staining pattern of M. berkeleyi was described in Blake (1996) as having intense staining on the first 4‒5 chaetigers. Magelona paulolanai sp. nov. is stained in same region, but only chaetiger four had the darkest stain. Magelona dakini was described as having finely unilimbate capillaries on chaetiger nine and Jones (1978) suggested that it had a narrowly pennoned aspect. Other species with rudimentary prostomial horns include Magelona sp. F sensu Uebelacker & Jones (1984), M. longicornis Johnson, 1901 and M. phyllisae Jones, 1963 but all three possess bidentate abdominal hooks. Etymology. This species is named after Dr. Paulo da Cunha Lana, a polychaete researcher whose publications on polychaetes have had great impact on the scientific growth of the first author (WFM). Dr. Lana also kindly introduced this author to the study of polychaetes back in 2007 during a short but fruitful meeting. Distribution. This species is known from Mamala Bay, Oahu, Hawaii and Guam in the Mariana Islands, 30‒100 m.Published as part of Magalhães, Wagner F., Bailey-Brock, Julie & Watling, Les, 2018, Four new species of Magelona (Annelida: Magelonidae) from Easter Island, Guam and Hawaii, pp. 379-396 in Zootaxa 4457 (3) on pages 387-390, DOI: 10.11646/zootaxa.4457.3.2, http://zenodo.org/record/145787
High water availability increases the negative impact of a native hemiparasite on its non-native host
No full textEnvironmental factors alter the impacts of parasitic plants on their hosts. However, there have been no controlled studies on how water availability modulates stem hemiparasites' effects on hosts. A glasshouse experiment was conducted to investigate the association between the Australian native stem hemiparasite Cassytha pubescens and the introduced host Ulex europaeus under high (HW) and low (LW) water supply. Cassytha pubescens had a significant, negative effect on the total biomass of U. europaeus, which was more severe in HW than LW. Regardless of watering treatment, infection significantly decreased shoot and root biomass, nodule biomass, nodule biomass per unit root biomass, F-v/F-m, and nitrogen concentration of U. europaeus. Host spine sodium concentration significantly increased in response to infection in LW but not HW conditions. Host water potential was significantly higher in HW than in LW, which may have allowed the parasite to maintain higher stomatal conductances in HW. In support of this, the delta C-13 of the parasite was significantly lower in HW than in LW (and significantly higher than the host). C. pubescens also had significantly higher F-v/F-m and 66% higher biomass per unit host in the HW compared with the LW treatment. The data suggest that the enhanced performance of C. pubescens in HW resulted in higher parasite growth rates and thus a larger demand for resources from the host, leading to poorer host performance in HW compared with LW. C. pubescens should more negatively affect U. europaeus growth under wet conditions rather than under dry conditions in the field
Leucothoe orkneyi Holman & Watling 1983
No full text<i>Leucothoe orkneyi</i> Holman & Watling, 1983 <p>Figs 15-18</p> <p> <i>Leucothoe orkneyi</i> Holman & Watling, 1983: 231-233, figs 12-14.</p> Diagnosis <p>Eyes medium, round. Mandibular palp long and narrow, art. 3 1/2-1/3 length of art. 2 (in original description verbally reported 1/3, but illustration shows 1/2). Cx 1 l:w subequal. Cx 3 subtrapezoidal, inferior margin serrate. Gn 1 carpus distal part about 8-9 x longer than wide, propodus ratio l:w = 6, dactylus reaching about 1/5 of propodus length. P 5-7 basis oval and not much broadened, with regularly rounded hind margin, ratio l:w 1.8 to 1.5; posterior margin strongly serrate (not mentioned in original description). Ep 2 posterodistally with upturned acute tip, Ep 3 with posterodistally rounded. T l:w = <3.</p> Type locality <p>Scotia Sea, east of South Orkney Islands; Eltanin 12, sta. 1079; 61°26’S, 40°55’W; 593- 598 m.</p> Material examined <p> <b>Australian Museum, Sydney</b></p> <p>P. 25494: Ross Ice-Shelf, McMurdo Sound, White Island, tide crack; 25 Jan. 1977; [approx. 78°08’S, 167°24’E]; 67 m depth; on rocky bottom encrusted with bryozoans and hydroids: 1 spec. 4 mm.</p> <p> <b>Belgian-Dutch Antarctic Expeditions</b></p> <p>(RBINS, Brussels, EABN 1966-67, coll. M. Steyaert & M. Meisch, RBINS I.G. 23694)</p> <p>EABN 1966-67: sta. 232; 25 Jan. 1967; Breid Bay, Baie Léopold III; 70°17’00”S, 24°15’E; 300 m, bottom trawl: 1 spec. 6 mm.</p> <p> <b>British Antarctic Survey, Cambridge</b></p> <p> <i>James Clark Ross</i> 179: sta. BIO4 – EBS-3D-E; Amundsen Sea; 74.390880°S, 104.767260°W; 506 m; Epibenthic Sled-Epinet: 1 spec. 4.5 mm, slide.</p> <p> <b>NIWA, Wellington</b></p> <p> NIWA 20875: <i>Tangaroa</i> sta. TAN0402/231; 4 Mar. 2004; off Balleny Islands; 67.4205017°S, 163.9391632°E to 67.4205017°S, 163.9391632°E; 111 m: 4 spec. 3.5-5 mm.</p> <p> <b> <i>Polarstern</i> cruises</b> </p> <p>(RBINS, Brussels, ANT XIII /3 (EASIZ I), coll. C. De Broyer & G. Chapelle, RBINS I.G. 28252; ANT XV/3 (EASIZ II), coll. C. De Broyer & Y. Scailteur, RBINS I.G. 28252; ANT XXII /3 (ANDEEP III), coll. C. De Broyer & B. Danis, RBINS I.G. 32565.)</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/005; 6 Feb. 1996; eastern Weddell Sea; SW of Kapp Norvegia; 71°40.40’S, 12°44.30’W; 229 m; dredge; Rauschert coll.: 3 spec. 4-6 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/006; 7 Feb. 1996; eastern Weddell Sea; 71°30.80’S, 13°31.44’W; 300 m; dredge; Rauschert coll.: 2 spec. 3-5 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/007; 8 Feb. 1996; eastern Weddell Sea; 71°28.60’S, 13°45.10’W; 279 m; dredge; Rauschert coll.: 1 spec. 4 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/016; 15 Feb. 1996; eastern Weddell Sea; 73°51’S, 22°24’W to 73°51’S, 22°25’W; 246-252 m; dredge; Rauschert coll.: 1 spec. 4 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/017; 16 Feb. 1996; eastern Weddell Sea; 73°19’S, 21°16’W, 447 m; dredge; Rauschert coll.: 4 spec. 2-5.2 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/024 MG 26; 21 Feb. 1996; eastern Weddell Sea; 71°8.10’S, 11°31.90’W, 118 m; Multibox Corer: 1 spec. 5 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/002 MG 27; 22 Feb. 1996; eastern Weddell Sea; 71°19’04”S, 12°24’48”W; 182 m; Multibox Corer: 3 spec. 3 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/002 MG 28; 22 Feb. 1996; eastern Weddell Sea; 71°19’06”S, 12°22’48”W; 159 m; Multibox Corer: 2 spec. 4, 5 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/002 MG 29; 22 Feb. 1996; eastern Weddell Sea; 71°18’36”S, 12°25’24”W; 181 m; Multibox Corer: 2 spec. 2,5 mm and 3,5 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/002 MG 30; 22 Feb. 1996; eastern Weddell Sea; 71°19’12”S, 12°27’W; 253 m; Multibox Corer: 1 spec. sex? 5 mm (with red eyes).</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/025 MG 31; 23 Feb. 1996; eastern Weddell Sea; 71°23’06”S, 14°19’48”W; 628 m; Multibox Corer: 1 spec. 5 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/026; 24 Feb. 1996; eastern Weddell Sea; 71°29’S, 14°19’W to 71°29’S, 14°19’W; 210-214 m; dredge 21; Rauschert coll.: 6 spec. 3-6.5 mm.</p> <p>ANT XIII /3 (EASIZ I): sta. PS39/032; 04 Mar. 1996; eastern Weddell Sea; 70°28’S, 8°15’W to 70°28’S 8°15’W; 283-286 m: 9 spec. 4-6 mm.</p> <p>ANT XV/3 (EASIZ II): sta. PS48/039; 29 Jan. 1998; eastern Weddell Sea; 70°52.8’S, 10°31.4’W; 237 m; Agassiz Trawl: ♂ 6 mm.</p> <p>ANT XXII /3 (ANDEEP III): sta. PS67/133-2-EBS; 16 Mar. 2005; western Weddell Sea, Powell Basin; 62°46.49’S, 53°3.50’W; 1584 m; EBS-Epinet: 2 juv. 4 mm; 20 spec. 4-5 mm; EBS-Supranet: 1 spec. 5 mm.</p> <p> <b>Polish Antarctic Expeditions (LPBO-UL, Łódź)</b></p> <p>3rd Polish Biol. Ant. Exp. 1974: sta. PABE III- 46; 4 Nov. 1974; Enderby Land, Alasheyev Bight, Opasnaya Bay; 67°30’S, 45°40’E; 40 m: 1 spec. 6.5 mm.</p> <p>9th Polish Ant. Exp.1985: sta. OC 419; 18 Jan. 1985; King George Island, Admiralty Bay, section 1; 62°09,0194’S, 58°26,510’W; 380 m; Van Veen Grab: 1 ad. 5 mm.</p> <p>9th Polish Ant. Exp. 1985: sta. OC 481; 23 Jul. 1985; King George Island, Admiralty Bay, Section I, 62°09.154’S, 58°26.929’W, 205 m, Van Veen Grab: 1 ad. 5 mm.</p> <p>9th Polish Ant. Exp. 1985: sta. OC 486; 10 Aug. 1985; King George Island, Admiralty Bay, section I; 62°09,067’S, 58°26,797’W; 270 m; Van Veen Grab: 1 spec.</p> <p>9th Polish Ant. Exp. 1985: sta. OC 517; 30 Oct. 1985; King George Island, Admiralty Bay, Section I; 62°09.149’S, 58°26.927’W; 212 m, Van Veen Grab: 1 spec. 4 mm.</p> <p>9th Polish Ant. Exp 1985: sta. OC 520; 3 Nov. 1985; King George Island, Admiralty Bay, section I; 62°09’S, 58°25’W; 335 m; Van Veen Grab: 2 spec.</p> <p> <b>Victoria Museum, Melbourne</b></p> <p> J 38265: <i>Aurora Australis</i> sta. AA93 127; MacRobertson Shelf, edge of Nielsen Basin; 67°16’07”S- 67°16’28”S, 65°25’14”E- 65°25’45”E; depth? [85 m?]: 1 spec. 3mm.</p> <p> J 38266: <i>Aurora Australis</i> sta. AA93 131; off Mac Robertson Land, northern end of Fram Bank; 67°05’02”S- 67°05’14”S, 68°58’48”E- 68°58’31”E; depth? ¨[208 m?]: 1 spec. 3mm.</p> <p> J 38268: <i>Aurora Australis</i> sta. AA93 158; Eastern Prydz Bay, off the Larsemann Hills; 68°54’53”S- 68°54’49”S, 76°37’02”E- 76°37’43”E; depth? [660 m?]: 4 spec. 3-4mm.</p> Redescription <p> <b>Length</b></p> <p>4-9 mm.</p> <p> <b>Head</b></p> <p>Anterior margin rounded, anterodistal margin rectangular with rounded corner. Mid-cephalic keel with acute projection, extending past epistome. Rostrum small.</p> <p>Eyes small, round, red colour remaining some time in alcohol (Holman & Watling 1983: 231).</p> <p>Antenna 1 one third of body length, flagellum 7-articulate, peduncle art. 1 width proximally less than twice article 2, disto-inferiorly with acute tooth, length art. 1 subequal to art. 2, art. 3 about 1/3 of art. 2, acc. flagellum not seen. Peduncle art. 3 + flagellum subequal to peduncle art. 2.</p> <p>Antenna 2 subequal in length with antenna 1, peduncle art. 4> art. 5, flagellum 6 arts.</p> <p>Mouthparts: Mandibles lacking molars, incisor and lacinia mobilis dentate; palp 3-articulate, art. 2 with 6 long lateral and 4-5 distal setae, art. 3 with 2 distal setae, 1/3 length of art. 2. Maxilliped IP small, ventrally fused, OP reaching about 1/5 of inner margin of palp art. 1; palp articles similar in length, all clearly longer than wide.</p> <p> <b>Peraeon</b></p> <p>Cx 1 smooth, length and width subequal; anterior margin smooth, facial setae absent.</p> <p>Gn 1 basis somewhat widened, lacking setae; ischium smooth; carpus basis about half as long as propodus, distal part linear and extremely narrow (width not much differing, about 9 long); propodus straight, 7-8 x as long as wide, palm minutely dentate with 12 short and up to 8 longer setae; dactylus smooth, reaching about 1/5 propodus length.</p> <p>Cx 2 subquadrangular, about as long as wide, much wider than Cx 3, distally smooth; anterior margin straight, anterodistal corner rectangular, inferior and posterior margin straight, facial setae absent.</p> <p>Gn 2 basis not inflated, on both margins up to 14 short setae and on anterior margin one longer one; carpus reaching about 1/3 propodus length, curved, distally truncate, with small serration, densely setose; propodus anterodistally with short acute prolongation and bundle of setae, posterior margin with many low humps, palm convex, proximally near dactylus-end widening with a characteristic blunt corner; one row of facial setae below the middle line; dactylus curved, both margins smooth, bare, reaching more than half of propodus length.</p> <p>Cx 3 length> width, anterior and posterior margin straight, distally rounded and irregularly serrate, facial setae absent.</p> <p>Cx 4 wider than long, smooth, bare, anterior margin scarcely convex, distal margin rounded, posterior margin shorter than anterior one, not excavate, facial setae absent.</p> <p>P 3, 4 basis slender, a bit wider than merus; merus anterodistally lengthened; dactylus reaching more than half length of propodus.</p> <p>Cx 5-7 facial setae absent.</p> <p>P 5-7 similar, bases l:w ratio about 1.9 to 1.5, anterior margins with slight serrations and small weak spines, posterior margins strongly serrate (not mentioned in original description).</p> <p> <b>Pleon</b></p> <p>Ep 1-2 with spines on distal margin, Ep 3 distally bare, but some short setae on posterior margin. Ep 1 posteroventral corner rounded, Ep 2 posteroventral corner acutely produced, Ep 3 posteroventral corner blunt and rectangular.</p> <p>Uropods: U 2 the shortest, with unequal rami (ratio 1.5), the shorter one shorter than peduncle.</p> <p>Telson ratio l:w> 3, tip tridentate because of two indentations near distal end, with a short seta inserted in each one.</p> Distribution <p>Circum-Antarctic (61°- 73°S, 8°- 58°W and 24°- 167°E; type material 60°35’S, 45°30’W).</p> Depth range <p>11-1584 m.</p> Remarks <p>The material examined here matches the description and figures of Holman & Watling quite well, but our specimens are always considerably smaller, found at shallower depth and their peraeopod bases are posteriorly serrate. Moreover the original description tells about specimens of 4.5-6.5 mm from 61°27’S, 41°55’W, while others from a similar area were between 6.5 and 9 mm, both localities from about 600 m depth. On p. 230-231 (loc. cit.) the authors wrote: “[...]of P 7, the basis of which appeared broadly rounded. Some slight variability in the degree of expansion of this article was seen [...], so its diagnostic value is questionable.”</p> <p>Thus it could very well be that this material consists of a group of closely related and morphologically extremely similar species.</p> <p> Holman & Watling (loc. cit.) compare their new species to <i>L. tridens</i> Stebbing, 1888, <i>L. miersi</i> Stebbing, 1888, <i>L. trailli</i> Thomas, 1882, <i>L. commensalis</i> Haswell, 1880, <i>L. diemensis</i> Haswell, 1880, <i>L. assimilis</i> J.L. Barnard, 1974 and <i>L. hyhelia</i> J.L. Barnard, 1970, which all differ from this new species in the shape of the first gnathopod. <i>L. panpulco</i> J.L. Barnard, 1961 and <i>L. uschakovi</i> Gurjanova, 1951 (up to 34 mm maximal length, 3000 m, see redescription in Krapp-Schickel & Vader 2012) have different bases on P 5-7, <i>L. ctenochir</i> K.H. Barnard, 1916 has a very characteristic palm on Gn 2.</p>Published as part of <i>Krapp-Schickel, Traudl & Broyer, Claude De, 2014, Revision of Leucothoe (Amphipoda, Crustacea) from the Southern Ocean: a cosmopolitanism concept is vanishing, pp. 1-55 in European Journal of Taxonomy 80</i> on pages 31-38, DOI: 10.5852/ejt.2014.80, <a href="http://zenodo.org/record/3860901">http://zenodo.org/record/3860901</a>
Decomposition of Bayer process organics: low-molecular-weight carboxylates
No full textThe degradation of twenty-one low-molecular-weight organic carboxylates has been studied at 90 and 180 °C, in a synthetic Bayer liquor consisting of 6 mol kg− 1 aqueous NaOH solution, for periods of up to 36 days. The reactions were monitored and the major degradation products identified by HPLC and NMR spectroscopy. The carboxylates chosen for the study were either possible intermediates or known products arising from the decomposition of organic matter in the Bayer process. Aliphatic carboxylates without hydroxyl substituents were stable at 90 °C but decomposed at 180 °C, except for formate, acetate, oxalate and succinate. The corresponding aromatic carboxylates were stable even at 180 °C. Both aliphatic and aromatic carboxylates with hydroxyl substituents were unstable at 90 °C except for lactate and 4-hydroxy-benzoate. The most frequently detected decomposition products for both aliphatic and aromatic carboxylates were formate, acetate, oxalate, succinate and lactate. Phenolate was also observed for some aromatic carboxylates. These products are briefly discussed with reference to possible mechanisms for the degradation reactions
Transconductance, carrier mobility and 1/f noise in Si/Si0.64Ge0.36/Si pMOSFETs
No full textWe briefly review recent work on enhancements in transconductance, maximum voltage gain, carrier mobility and velocity overshoot in Si/Si0.64Ge0.36/Si p-channel metal-oxide semiconductor devices and then discuss the superior 1/f noise properties in more detail. The results indicate the growth and processing chanllenges which must be met in order to improve device performance
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