1,179 research outputs found

    FIGURE 6 in A new species of Duttaphrynus (Anura: Bufonidae) from Northeast India

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    FIGURE 6. Lateral view of head showing distinct tympanum in A. D chandai, Holotype (in life (3, ZSI A 11453); B. D. chandai (3, AVCM A 1072); C. D. chandai, (Ƥ, paratype, A 1044); D. D.stuarti, (3, A0743); E. D. melanostictus (Ƥ, A 0616); F. D. wokhaensis (Ƥ, SVL 88.69); G. D. kiphirensis (3, SVL 67.72); H. D. melanostictus (3, A 0850), SVL 55.5; I. D. mamitensis (Ƥ, SVL 88.93mm); J. D. nagalandensis (Ƥ, SVL 49 mm); K. D. manipurensis (3, SVL 48.3 mm); L. D. mizoramensis (3, SVL 59.1mm).Published as part of Das, Abhijit, Chetia, Mitali, Dutta, Sushil Kumar & Sengupta, Saibal, 2013, A new species of Duttaphrynus (Anura: Bufonidae) from Northeast India, pp. 336-348 in Zootaxa 3646 (4) on page 345, DOI: 10.11646/zootaxa.3646.4.2, http://zenodo.org/record/21951

    Duttaphrynus chandai Das, Chetia, Dutta & Sengupta, 2013, new species

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    Duttaphrynus chandai new species (Fig 2 & 3, Table I) Holotype: ZSIC A 11453, adult male from Khonoma village, 25 ° 38. 505 ’ and 94 ° 01.479’, 1568 m. asl., collected on 18 th march 2008, small rocky first order stream, ca. 2-4 m wide at the collection location. Collected by A. Das and P. Choudhury. Paratypes: Adult females (ZSIC A 11456) and a sub-adult female (ZSIC A 11455) from Khonoma village, 25 ° 38. 505 ’ and 94 ° 01.479’, 1568 m. asl., collected on 18 th march 2008, small rocky 1 st order stream; adult females ZSIC A 11454 and AVCM A 1044 from Thekhekhwei hill, 25 ° 38. 071 ’ and 93 ° 56.652, 1787m. asl., 5 km east to Khonoma village, Nagaland state of India, 29 September 2010, at 1830 h., from a slash and burn (Jhum) cultivation area close to a small rocky stream. Collector A. Das; adult male AVCM A 0 964, 25° 37. 733 ’ and 94 ° 00.623’, 1775 m. asl., Hievibakie hill, 8 km east to Khonoma village, 16 September 2009 at 0 800 h. near Dzuku Base camp, under rotten log ca. 5 m away from motorable gravel road. Collector A. Das. Diagnosis: These specimens were allocated to Duttaphrynus for showing the following suit of diagnostic characters: presence of cranial ridges, parotid glands; fingers free with moderate toe webbing, rough and tuberculated skin, absence of parietal ridge, tarsal ridge and tibia gland. This new species is diagnosable from congeneric species in showing the following suite of characters: Large size (adult male, 67.5–88.1 and female, 61.2–86.1 mm), head much wider, tympanum hidden or partly visible under a skin fold, small eye, obscure cranial ridges, fingers long and thin, pointed warts and presence of a cream coloured mid dorsal line. Morphometric and mesural features of holotype and paratypes are listed in Table I Description of holotype (ZSIC A 11453; adult male): A large toad (SVL 67.5 mm), habitus stout, cloacal opening at upper level of thighs; head large (HL/SVL ratio 0.29) wider than long (HL/HWAJ ratio 0.82), and about three and half times of its depth (HL/HDN ratio 3.55); snout more than one third of head length (SL:HL ratio 0.39), obtusely pointed when viewed dorsally and laterally; barely projecting beyond mandible; angle of jaw extends beyond posterior corner of the eye up to the anterior part of the parotid; nostrils rounded not raised and with a marginal dermal flap on dorsal side, placed dorsolaterally, nearer to the tip of snout than to eye (EN/NS ratio 1.09); internarial distance smaller than inter orbital distance (INS/IOS ratio 0.60) but equal to distance from anterior margin of eye to nostril (INS/EN ratio 1.00); eye large (ED/HL ratio 0.37); its diameter greater than eye to nostril distance (ED/EN ratio 1.75); pineal ocellus absent; interorbital space flattened; canthus rostralis slightly oblique; loreal region greatly concave; a highly depressed symphysial knob on anterior edge of mandible; Choanae rounded and well separated, vomerine ridge posterior to choanae and perpendicular to the body axis.; tongue oval, two lateral flaps at free end, lacking papillae and median lingual process; pupil elliptical; tympanum slightly visible mostly hidden under skin fold. Canthal, supraorbital and parietal cranial ridges present. Parotid gland wide and elongated (PGL: PGB ratio = 3.12), less than ¹ / 3 rd of SVL (PGL: SVL ratio 0.27), separated from each other by a distance (10.82 mm) less than its length (PGL 17.98 mm). Fore limbs moderately long (FLL/SVL ratio = 0.88) and stout; fingers slender, free of web; relative length of fingers: II<I<IV<III; finger tips round slightly swollen; subarticular tubercles prominent; outer metacarpal large and oblong; inner metacarpal tubercle small elongated not extending out under finger I. Hindlimb long (HLL:SVL ratio 1.39), Tibia long (TBL/SVL ratio 0.43), more than three and half times of its width (TBL/TBW ratio 3.60); tibia tarsus articulation reaches the middle of the parotid gland; heels remain seperated when hind limbs are flexed and held perpendicular to body; toe tips weakly differentiated, not truncate apically; lateral fringes present on all toes; relative length of toes: 1 <2 <5 <3 <4; Toe webbed (Webbing formula I 1 ½- 1 ½ II 1 ½- 2 ½ III 1 ½- 3 ½ IV 3 ½- 1 ½ V. Subarticular tubercles on toes indistinct; super numerary tubercles on hands and toes; outer metatarsal tubercle depressed; an elongated inner metatarsal tubercles (IMT:Toe I ratio 0.30); cloacal opening directed posteroventrally, little below the upper level of the thigh. Skin on dorsal surface granulated, with irregularly arranged scarce pointed tubercles. Head between eye smooth, flat tubercles on upper eyelid, large irregular shaped tubercle on tympanic region, a patch of irregular wart behind eye; two rows of enlarged tubercles on flank; forelimb upper part with small pointed tubercles, hindlimb upper surface with large pointed tubercles. Ventrally trunk and chin warty; lower part of shank and foot finely tuberculated, thigh with large flat tubercles. Condition of the type series: The Type series (ZSIC A 11453, ZSIC A 11454, ZSIC A 11455, ZSIC A 11456, AVCM A 0 964 and AVCM A 1044) was well preserved. However, all the type specimens had lateral incision which was made to determine the sex of the individual. In the holotype (ZSIC A 11453) and paratype (AVCM A 0964) a small incision was made to remove thigh (upper) muscle for future molecular analysis. Secondary sex characters: male: Presence of a small nuptial pad at the base of first finger. The breeding male developed reddish tinge on dorsum; warts were large, flat and without black tip; digit tips were not melanistic. A thin line on the ventral side from snout to vent and also undersurface of limbs. Adult females (SVL: 81.0— 86.1 mm) were almost equal to the males (SVL: 58.0— 88.1 mm) and with hidden tympanum, comparatively rough dorsum, melanistic digital tips and wart tips. Colour: In life, forehead and trunk brown with black blotches, more intense between the parotid; laterally pale yellow. Canthus yellow. Parotid black with yellow dots. An obscure yellow mid dorsal line extended from snout to vent. Upper surfaces of fore and hind limbs pale brown with dark brown patches, phalanges pale brown. Trunk on ventral aspect dirty white with variegated brown patches, rest of the ventrum dusty white. Variations: A female (ZSIC A 11456) head was comparatively wider (HL: HW = 0.70) than other members of the type series (HL:HW = 0.84 + 0.02). The female paratype (ZSIC A 11454) showed partial parietal ridge. A great variation in the shape of the parotid gland also occurred amongst the members of the type series. The parotid gland was elongated (ZSIC A 11453, A ZSIC A 11455, ZSIC A 11456, AVCM A 0964) except in ZSIC A 11454 and AVCM A 1044 where it was bean shaped. One female (ZSIC A 11455) had alternate light and dark bands on hind limb. Etymology: Named after Shyamal Kumar Chanda, a prominent Indian amphibian biologist. Suggested common name: Nagaland Montane torrent toad Ecological notes: The type locality of Khonoma, situated ca. 20 km west of Kohima (Nagaland State capital), runs along a ridge extending from the terraced rice field in the valley up to the uplands of the Barail hill range. This domain, spreading over ca. 123 sq. km., includes Khonoma Nature Conservation and Tragapon Sanctuary covering an area of over 70 sq. km. The forested slopes of the village are relatively undisturbed, baring a few patches of jhum-cleared cultivations. Khonoma enjoys a sub-tropical to temperate climate with heavy rains from the month of May to August and little rainfall during September to October. The dry season is usually from the month of November till April. The environmental temperature in the summer months goes up to a maximum of 30 ºC and a minimum of 4 ºC. This area is the part of Mizoram-Manipur-Kachin Rain Forest biogeographic zone and is characterized by subtropical broadleaf hill forest and Rhododendron forest. The new species of toad was observed both during day and night between March to September in recently felled Jhum cultivation field, forest trail and under rotten log at altitude from 1568 to 1762 m (Fig 4). Breeding aggregation was observed in small streams (width ~ 2–4 m) of first order (Strahler, 1952) near human habitation and forest edges. The individuals were found to use stagnant water pool with accumulated leaf litter. The water pools of the streams were surrounded by large rocks. Calling males were recorded on a cloudy day (10.25 AM IST) of 18 March 2008 with environmental parameters as air temperature 13.8 o C, water temperature 11 o C, humidity 77 %, water pH 7.8. Eggs were laid in long string inside thick gelatinous mass and advanced embryos (Gosner stage 16–18) were observed in “side water pool” of a small stream (first order) beside terrace cultivation on 21 March 2008 (Fig 5). Eggs were rounded with pigmented animal pole. The breeding period coincided with early breeders like Rhacophorus burmanus, Rhacophorus maximus and Hyla annectens in the region. During the breeding season, this species (D. chandai) is relatively abundant and observed in modified as well as forested habitats not far from flowing water sources. 85.0 (Ƥ) Juveniles observed in the month of September-October inhabiting forest floor and roadside habitats. This species is locally called as “Theiiu” in Angami Naga dialect. The species was observed between elevations 1568 and 1787 m. Currently the species is only known from localities around Khonoma and Dzuleke villages of Kohima district. Syntopic species of anurans recorded from the type locality are Duttaphrynus himalayanus, Rhacophorus burmanus, Hyla annectens, Amolops sp, Rhacophorus maximus. The reptile species found in sympatry are Calotes jerdoni, Sibynophis collaris, Protobothrops jerdoni, Ovophis monticola, Rhabdophis nuchalis and Ptyas nigromarginatus. Comparison: From other members of the genus Duttaphynus, the new species differs in showing the following characters, listed by species (characters in parentheses refer to congener being compared with the new species from Khonoma) The new species differs from D. melanostictus (Schneider) in showing smaller snout, comparatively longer mandible eye distance, absence of tympanum, longer tibia, absence of preorbital, postorbital and orbitotympanic ridges, 1 st finger longer than 2 nd (vs. smaller size, longer snout, smaller mandible eye distance, distinct tympanum, smaller tibia, presence of preorbital, postorbital and orbitotympanic ridges, 2 nd finger longer than 1 st), from D. himalayanus (Günther) in showing 1 st finger longer than second, absence of tympanum, preorbital, postorbital and orbitotympanic ridges (vs. 2 nd finger longer than 1 st, presence of tympanum, preorbital, postorbital and orbitotympanic ridges), from D. stuarti (Smith) in showing cranial ridges, absence of tympanum, subarticular tubercle not prominent (vs. without bony ridges, distinct tympanum, prominent subarticular tubercle); from D. cyphosus (Ye) in showing elongated and broad parotid, indistinct or absence of tympanum, absence of bracket like curves on interorbital space (vs. triangular parotid, small distinct tympanum, dark round curves facing each other like ‘brackets’ along the supraorbital ridge); from D. scaber (Schneider) in showing elongated parotid gland, absence of tympanum, preorbital, postorbital and orbitotympanum ridges, 1 st finger longer than the 2 nd, toe webbing: I 1 ½– 1 ½ II 1 ½– 2 ½ III 1 ½– 3 ½ IV 3 ½– 1 ½V (vs. rounded parotid gland, tympanum about ½ of the eye diameter, presence of preorbital, postorbital and orbitotympanic ridges, 1 st finger smaller than 2 nd, toe web I 0— 1 II 1-2 III 2–3 ½ IV 3 ½– 1 V), from D. crocus (Wogan, Win, Thin, Lwin, Shein, Kyi, and Tun) in showing absence of preorbital, postorbital and orbitotympanum ridges, 1 st finger longer than the 2 nd, toe webbing: I 1 ½– 1 ½ II 1 ½– 2 ½ III 1 ½– 3 ½ IV 3 ½– 1 ½V (vs. presence of preorbital, postorbital and orbitotympanum ridges, 1 st finger smaller than the 2 nd, toe webbing: I 2–3 II 1–2 ½ III 1 ½– 3 ½ IV 3 ½– 1 ½V); from D. stomaticus (Lütken) in showing cranial ridges, absence of tympanum, longer hind limb (vs. no cranial ridge, distinct tympanum, short hind limb); from D. kiphirensis (Mathew and Sen), D. manipurensis (Mathew and Sen), D. mizoramenis (Mathew and Sen), D. mamitensis (Mathew and Sen), D. nagalandensis (Mathew and Sen), D. wokhaensis (Mathew and Sen) in showing absence of distinct tympanum, and absence of preorbital, postorbital and orbitotympanic ridges (vs. distinct tympanum and presence of preorbital, postorbital and orbitotympanic ridges) (Fig. 6). The new species also shows differences from Ingerophrynus macrotis (Boulenger) in showing absence of tympanum, strong parietal ridge (vs. distinct tympanum, weak parietal ridge), from Bufo pageoti Bourret in showing cephalic ridges, absence of pineal ocellus, toe webbing: I 1 ½– 1 ½ II 1 ½– 2 ½ III 1 ½– 3 ½ IV 3 ½– 1 ½V (vs. no cephalic ridge, presence of pineal ocellus, toe webbing: I 1 – 1 ½ II 1–2 III 1–2 ½ IV 2 ½– 1 V) and from Phrynoidis aspera (Gravenhorst) in showing absence of tympanum, toe web incomplete, TTA reaches to the parotid gland, parotid broad and elongated, absence of orbitotympanic ridge (vs. distinct tympanum, toes entirely webbed, TTA reaches tip of snout or beyond, parotid small and triangular, presence of orbitotympanic ridge). Mathew and Sen (2009) described six new species of Duttaphrynus based on seven specimens collected from Northeast Indian states. We conducted PCA involving the holotypes of Mathew and Sen (op cit) species, and compared with Duttaphrynus melanostictus and specimens of new species described herein (Fig 7). We have observed D. wokhaensis to be deeply embedded into the D. melanostictus cluster. Mathew and Sen (2009) also pointed out its close affinity to D. melanostictus and D. himalayanus. Mathew and Sen (2009) stated that D. wokhaensis differed from D. melanostictus and D. himalayanus in having nostril equidistant from eye and snout tip and, white cranial ridges and warts. The examination of holotype (V/A/ERS/ZSI/ 800) revealed that the morphometry of this specimen fall in the range of morphometry of D. melanostictus and the specimen has the nostril closer to the snout than the eye (EN = 4.85; NS = 3.57). Further, stray individuals having white cranial ridges and warts were collected from amongst D. melanostictus population of Guwahati (AVCM A0326) and Tangla (AVCM A0850). We consider D. wokhaensis as a variety of D. melanostictus and we propose to keep this species under nomen D. melanostictus. Colouration is well known to be highly variable in many groups of anurans especially in highly polymorphic group like Duttaphrynus melanostictus and is seldom useless in taxonomy (Qiucke, 1993). Thus we presume that difference in colour as reported in D. wokhaensis may be intraspecific variation. ZSI/ ZSI/ ZSI/ ZSI/ ZSI/ ZSI/ Mus. ERS ERS ERS ERS ERS ERS No A0894 A0896 A0893 A0898 A0895 A0899 A0891 A0884 A0890 A0885 794 798 795 800 799 796Published as part of Das, Abhijit, Chetia, Mitali, Dutta, Sushil Kumar & Sengupta, Saibal, 2013, A new species of Duttaphrynus (Anura: Bufonidae) from Northeast India, pp. 336-348 in Zootaxa 3646 (4) on pages 338-346, DOI: 10.11646/zootaxa.3646.4.2, http://zenodo.org/record/21951

    Dynamics of Network Formation Processes in the Co-Author Model

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    This article studies the dynamics in the formation processes of a mutual consent network in game theory setting: the Co-Author Model. In this article, a limited observation is applied and analytical results are derived. Then, 2 parameters are varied: the number of individuals in the network and the initial probability of the links in the network in its initial state. A simulation result shows a finding that is consistent with an analytical result for a state of equilibrium while it also shows different possible equilibria.Dynamics, Network, Game Theory, Model,Simulation, Equilibrium, Complexity

    RCSB Protein Data Bank: A Resource for Chemical, Biochemical, and Structural Explorations of Large and Small Biomolecules

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    The Research Collaboratory for Structural Bioinformatics (RCSB) Protein Data Bank (PDB) supports scientific research and education worldwide by providing access to annotated information about three-dimensional (3D) structures of macromolecules (e.g., nucleic acids, proteins), and associated small molecules (e.g., drugs, cofactors, inhibitors) in the PDB archive. Researchers, educators, and students use RCSB PDB resources to study the shape and interactions of biological molecules and their implications in molecular biology, medicine, biotechnology, and beyond. RCSB PDB supports development of standards for data deposition, representation, annotation, and validation of atomic structural data obtained from various experimental methods. Uniform representation of PDB data is essential for providing consistent search and analysis capabilities for all PDB users, from beginning students to domain experts. The RCSB PDB Web site provides tools for searching, visualizing, and analyzing PDB data, including easy exploration of chemical interactions that stabilize macromolecules and play important roles in their interactions and functions. In addition, educational resources are available for free and unrestricted use in the classroom for exploring chemistry and biology at the molecular level.This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Chemical Education, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://dx.doi.org/10.1021/acs.jchemed.5b00404Peer reviewe

    Novel Ni foam catalysts for sustainable nitrate to ammonia electroreduction.

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    Electrochemical nitrate reduction (NO3-RR) is considered a promising approach to remove environmentally harmful nitrate from wastewater while simultaneously producing ammonia, a product with high value. An important consideration is the choice of catalyst, which is required not only to accelerate NO3-RR but also to direct the product selectivity of the electrolysis toward ammonia production. To this end, we demonstrate the fabrication of novel Ni foam catalysts produced through a dynamic hydrogen bubble template assisted electrodeposition process. The resulting foam morphology of the catalyst is demonstrated to crucially govern its overall electrocatalytic performance. More than 95% Faradaic efficiency of ammonia production was achieved in the low potential range from -0.1 to -0.3 V vs. RHE. Hydrogen was found to be the only by-product of the nitrate reduction. Intriguingly, no other nitrogen containing products (e.g., NO,N2O, or N2) formed during electrolysis, thus indicating a 100% selective (nitrate→ammonia) conversion. Therefore, this novel Ni foam catalyst is a highly promising candidate for truly selective (nitrate→ammonia) electroreduction and a promising alternative to mature copper-based NO3-RR benchmark catalysts. Excellent catalytic performance of the novel Ni foam catalyst was also observed in screening experiments under conditions mimicking those in wastewater treatment

    Healthcare 4.0 (and 5.0):Digitising Health and Care

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    This chapter explores the transformative impact of people flow modelling in the context of Healthcare 4.0 (and 5.0). It suggests the links between the implementation of suitable technology and that of clinical need and, by an example, FND (Functional Neurological Disorder). Emerging areas such as AI (Artificial Intelligence), IoT (Internet of Things) and Data Analytics will be essential. By investigating people flow modelling in the healthcare sector, the chapter aims to elucidate its role in creating smart, responsive, and patient-centric environments in home and community settings. Whilst the example is that of FND the same principles can be applied to other clinical areas. The chapter proposes an example ‘Flow’ method and partnership way of working that encapsulates health sector needs, academic research and rigor and industry experience in order to deliver an accelerated and sustainable change in the way that patient-centric healthcare is delivered, taking account of patient (and person-centric) flow. Finally, whilst the deployment of technology presents new opportunities for the delivery of care and new ways of working it does not come without the need to acknowledge, and mitigate, the risk of depending upon specific technologies. In this respect lessons can, and must, be learned from other sectors

    A Review Of Research By Soumitra Dutta Titled “Strategies For Implementing Knowledgebased Systems”

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    The management of organizational knowledge, a relatively new and challenging concept for most organizations, is introduced and discussed in this paper. Around this general topic, the author, Dr. Dutta conducted a series of important concepts from knowledge, organizational knowledge or organizational knowledge assets, Knowledge-Based Systems (KBS’s), to implementation strategies for KBS’s. There is an increasing consensus that the effective management of knowledge is an important basis of competitive advantage for corporations, and that KBS’s can have an important role in the management of organizational knowledge at all levels. Based on an understanding that with considerable progress in the underlying technologies, the major challenges in the implementation of KBS’s have evolved from technical matters and to organizational and strategic issues, Dr. Dutta proposed four different strategies ( guided, specialist, dispersed points, and dispersed clusters) and described them in relation to the different levels of organizational knowledge and the locus of responsibility for the development of KBS’s. Then, the technical, managerial and strategic implications of each of the four strategies have been discussed

    Applications of balance optimization subset selection

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    Balance Optimization Subset Selection (BOSS) is a framework designed to be used for causal inference on observational data. The theoretical foundation for the BOSS framework has been provided in the literature; this thesis aims to provide some examples of the practical value of BOSS by using it on two problems. The first application is using BOSS to determine a subset of users who would be suitable targets for marketing efforts, and the second application is using BOSS to identify potential first-round upsets in the NCAA basketball tournament. Finally, this thesis delves into another area of college basketball and attempts to model the process of the NCAA tournament selection committee using a decision tree.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2018-08-01The student, Shouvik Dutta, accepted the attached license on 2016-07-19 at 12:51.The student, Shouvik Dutta, submitted this Thesis for approval on 2016-07-19 at 12:54.This Thesis was approved for publication on 2016-07-21 at 14:08.DSpace SAF Submission Ingestion Package generated from Vireo submission #10013 on 2016-11-10 at 12:21:00Made available in DSpace on 2016-11-10T18:27:07Z (GMT). No. of bitstreams: 2 DUTTA-THESIS-2016.pdf: 645024 bytes, checksum: 2db51a406961fe95b3cc42b8d0e55feb (MD5) LICENSE.txt: 4210 bytes, checksum: c742995ea6b0e1b88acbf8698e6a703a (MD5) Previous issue date: 2016-07-21Embargo set by: Seth Robbins for item 95292 Lift date: 2018-11-10T18:28:02Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemLimited Restriction Lifted for Item 95292 on 2018-11-11T10:15:19Z

    Similarities between 2D and 3D convection for large Prandtl number

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    Using direct numerical simulations of Rayleigh-B\'enard convection (RBC), we perform a comparative study of the spectra and fluxes of energy and entropy for large and infinite Prandtl numbers in two (2D) and three (3D) dimensions. We observe close similarities between the 2D and 3D RBC, in particular the kinetic energy spectrum Eu(k)k13/3E_u(k) \sim k^{-13/3}, and the entropy spectrum exhibits a dual branch with a dominant k2k^{-2} spectrum. We showed that the dominant Fourier modes in the 2D and 3D flows are very close

    Morphology Matters: Tuning the Product Distribution of CO 2 Electroreduction on Oxide-Derived Cu Foam Catalysts

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    Mesoporous Cu foams formed by a template-assisted electrodeposition process have been identified as CO2 electrocatalysts that are highly selective toward C2 product formation (C2H4 and C2H6) with C2 efficiencies (FEC2) reaching 55%. The partial current of C2 product formation was found to be higher than that of the (parasitic) hydrogen evolution reaction (HER) at any potential studied (−0.4 to −1.0 vs the reversible hydrogen electrode). Moreover, formate production could largely be suppressed at any applied potential down to efficiencies (FEformate) of ≤6%. A key point of the Cu foam catalyst activation is the in operando reduction of a Cu2O phase, thereby creating a large abundance of surface sites active for C–C coupling. The cuprous oxide phase has been formed after the Cu electrodeposition step by exposing the large-surface area catalyst to air at room temperature. The superior selectivity of the Cu foam catalyst studied herein originates from a combination of two effects, the availability of specific surface sites for C–C coupling [dominant (100) surface texture] and the temporal trapping of gaseous intermediates (in particular CO and C2H4) inside the mesoporous catalyst material during CO2 electrolysis. A systematic CO2 electrolysis study reveals a strong dependence of the C2 efficiencies on the particular surface pore size of the mesoporous Cu catalysts with a maximal FEC2 between 50 and 100 μm pore diameters
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