7,168 research outputs found
Sol Duc Falls rainbow, Olympic National Park, date unknown
No full textRainbow at Sol Duc Falls.
Image information provided by Olympic National Park staff
Sol Duc River at the Salmon Cascades showing several people observing the rapids, Olympic National Park, date unknown
No full textSol Duc River -- Salmon Cascades.
Sol Duc River also known as Soleduck River [cataloger's note].
Image information provided by Olympic National Park staff
Sol-gel derived hydroxyapatite, fluorhydroxyapatite and fluorapatite coatings for titanium implants
No full textCurrently, most titanium implant coatings are made using hydroxyapatite and a
plasma-spraying technique. There are however limitations associated with the
plasma-spraying process including; poor adherence, high porosity and cost. An
alternative - the sol-gel technique offers many potential advantages but is
currently lacking research data for this application.
Hydroxyapatite (HA), fluorhydroxyapatite (FHA) and fluorapatite (FA) have
been synthesised by a sol-gel method. Calcium nitrate and triethyl phosphite
were used as precursors under an ethanol-water based solution. Different
amounts of ammonium fluoride (NH4F) were incorporated for the preparation of
the FHA and FA sol-gels. Optimisation and characterisation of the sol-gels was
carried out using, X-ray Diffraction (XRD), High Temperature X-Ray Diffraction
(HTXRD), Fourier Transform Infrared Analysis (FTIR) and Differential Thermal
Analysis (DTA).
Rheology and hydrophilicity of the sol-gels showed that increasing fluoride ion
substitution caused an increase in viscosity and contact angle.
The dissolution (Ca2+ and PO4
3-rates) rates of the fluoride-substituted powders
from the sol-gels were considerably lower than that of HA and all rates could be
decreased by increasing the sintering temperature. This suggests the
possibility of tailoring the solubility of any coatings made from the sol-gels
through fluoride ion substitution and increased sintering temperature.
A spin coating protocol has been established for coating the sol-gels onto
titanium. Increasing the coating speed decreased the porosity and thickness of
the coatings. Bond strengths to titanium were investigated. Fluoride substitution
and sintering temperature were shown to be important factors. Cellular proliferation studies revealed that increasing the level of fluoride
substitution in the apatite structure significantly increased the biocompatibility
of the material.
The sol-gel technique may be an alternative to plasma spraying for coating
titanium implants. Furthermore it may also be suitable for producing HA, FHA
and FA as bone grafting materials
Performance of immobilized bacterial alpha-amylases in methyltriethoxsilane / tetraetoxysilane sol-gel matrices
No full textThe large number of studies related to the field of biomolecules
encapsulation in sol-gel hosts clearly indicates that this approach can be
considered as a powerful alternative to traditional encapsulation procedures
involving biopolymer hosts. In this study, α-amylase was immobilized, by using
the sol-gel technique, in silica particles obtained from hydrolysis and
polycondensation of tetraethoxysilane (TEOS) and a mixture of
methyltriethoxysilane (MTES) and tetraethoxysilane. The influence of the pH and
temperature of free and immobilized α-amylase were compared. It was shown
that the relative activities of immobilized enzymes are higher than those of free
enzymes over broader pH and temperature ranges. The Michaelis constant and
the maximum rate of starch hydrolysis reaction were calculated by fitting the
experimental data to the Michaelis-Menten equation. It was found that KM and
Vmax values of the immobilized enzyme were smaller than those of the free
enzyme
Novel sol–gel preparation of (PO)–(CaO)–(NaO)–(TiO) bioresorbable glasses (X = 0.05, 0.1, and 0.15)
No full textQuaternary phosphate-based glasses in the PO–CaO–NaO–TiO system with a fixed PO and CaO content of 40 and 25 mol% respectively have been successfully synthesised via sol–gel method and bulk, transparent samples were obtained. The structure, elemental proportion, and thermal properties of stabilised sol–gel glasses have been characterised using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), P nuclear magnetic resonance (P NMR), titanium K-edge X-ray absorption near-edge structure (XANES), fourier transform infrared (FTIR) spectroscopy, and differential thermal analysis (DTA). The XRD results confirmed the amorphous nature for all stabilized sol–gel derived glasses. The EDX result shows the relatively low loss of phosphorus during the sol–gel process and Ti K-edge XANES confirmed titanium in the glass structure is in mainly six-fold coordination environment. The P NMR and FTIR results revealed that the glass structure consist of mainly Q and Q phosphate units and the Ti cation was acting as a cross-linking between phosphate units. In addition DTA results confirmed a decrease in the glass transition and crystallisation temperature with increasing NaO content. Ion release studies also demonstrated a decrease in degradation rates with increasing TiO content therefore supporting the use of these glasses for biomedical applications that require a degree of control over glass degradation. These sol–gel glasses also offer the potential to incorporate proactive molecules for drug delivery application due to the low synthesis temperature employed
Heart Lake, Olympic National Park, date unknown
No full textHeart Lake, early spring before complete melting, looking north, east end of High Divide, drains into Sol Duc Valley.
Image information provided by Olympic National Park staff
Anarsia choana Park 1995
No full text13. Anarsia choana Park, 1995 (Figs. 13, 34, 53, 53 a–c) Anarsia choana Park, 1995: 61; Ponomarenko, 2009: 345. TL: Taiwan (Taipei). The holotype in USNM. Diagnosis. Adult (Figs. 13, 34): Wingspan, 11.5 mm. The species is superficially similar to A. patulella (Walker), but can be distinguished from the latter by the forewing: the blackish streak below costal patch in cell poorly developed, the long hair pencil on the underside of forewing absent, and the second segment of labial palpus in male (Fig. 34) greatly elongated anteriorly with long scale tufts. It can also be easily distinguished by the male genitalia with the hook-shaped basal process near the base of the left valva and the short-stalked, palmate-modified scales. Male genitalia (Figs. 53, 53 a–c): Uncus short, broadened basally, pointed apically; socius ovate. Tegumen longer than valva, slightly narrowed medially. Left valva semiovate, with a long, narrow, strongly curved process basally and a patch of palmately modified scales distally. Right valva slightly elongate, with membranous semiovate lobes on costa medially; patch of modified scales similar to that of left valva. Phallus slender, curved, as long as valva. Material examined. VIETNAM: 1 ♂, Bac Khan Prov., Ba Be Nat. Park, 40m, 18 vi 2004 (KT Park & N. Cuong), gen. slide no. CIS- 6405; 1 ♂, Nhin Binh Prov., Cuc Phuong Nat. Park, 300m, 23 iv 2006 (Park, Kim & Kang), gen. slide no. CIS- 6429. CAMBODIA: 1 ♂, Pursat Prov., Samkos, 12 o 12 ’ 41 ’’N, 102 o 54 ′ 37 ″E, 17 ii 2012 (YS Bae, YD Ju, BS Park), gen. slide no. CIS- 6428. Distribution. Vietnam (new record; Bac Khan, Nhin Binh Prov.).Published as part of Bae, Yang-Seop, Shin, Young-Min, Na, Sol-Moon & Park, Kyu-Tek, 2016, The genus Anarsia in Cambodia and the Northern Vietnam (Lepidoptera, Gelechiidae), with descriptions of ten new species and a catalogue of the genus in the Central-East Asia, pp. 227-252 in Zootaxa 4061 (3) on page 237, DOI: 10.11646/zootaxa.4061.3.2, http://zenodo.org/record/26696
A study on the preferable preparation method of SPEEK/BPO4 composite membranes via an in situ sol-gel process
No full textSulfonated poly(ether ether ketone) (SPEEK)/boron phosphate (BPO4) composite membranes for polymer electrolyte fuel cells (PEFCs) were prepared via an in situ sol-gel process in our previous study [P. Krishnan, J.-S. Park, C.-S. Kim, Preparation of proton-conducting sulfonated poly(ether ether ketone)/boron phosphate composite membranes by an in situ sol-gel process, J. Membr. Sci. 279 (2006) 220]. Proton conductivity of the composite membranes increased with increasing the amount of BPO4 up to 40 wt.% due to the increasing BPO4 particle size. In this study, the effect of several variables such as reaction time, reaction temperature and ionic form of solution-casting SPEEK polymers on the relationship between the size of inorganic particles and proton conductivity of the membranes was investigated for the preparation of SPEEK/BPO4 composite membranes. The composite membranes were characterized using FT-IR, SEM, DSC, TGA and proton conductivity. Among the variables, reaction time and reaction temperature were not dependent on the proton conductivity and size of BPO4 in the in situ sol-gel process. However, the ionic form of solution-casting polymers for the composite membranes significantly influenced the size of BPO4 particles. At the same amount of BPO4 in the composite membranes, the composite membrane using W-form polymer made the BPO4 particle size five to six times higher than that using Na+-form, polymer. Water uptake of the former composite membrane (in particular, an amount of freezable water) was higher than the latter due to the bigger size of BPO4, and the proton conductivity of the former composite membrane increased. As a result, it can be recommended that the preparation of the composite membranes using H+-form polymer is preferable via the in situ sol-gel process. (c) 2008 Elsevier B.V. All rights reserved
Stable sol-gel microstructured and microfluidic networks for protein patterning
No full textWe demonstrate the formation of micropatterned sol-gel structures containing active proteins by patterning with polydimethylsiloxane (PDMS) microchannels. To transport sol solution efficiently into the hydrophobic PDMS microchannels, a hydrophilic-hydrophobic block copolymer was used to impart hydrophilicity to the PDMS microchannels. Poor adhesion of the micropatterned gel structure onto glass slides was improved by treating the glass surface with a polymeric substrate. To minimize cracks in the gel microstructure, hybrid matrices of interpenetrating organic and inorganic networks were prepared containing the reactive organic moieties polyvinylalcohol or polyvinylpyrrolidone. Retention of biochemical activity within the micropatterned gel was demonstrated by performing immunobinding assays with immobilized immunoglobulin G (IgG) antibody. The potential application of microfluidics technology to immobilized-enzyme biocatalysis was demonstrated using PDMS-patterned microchannels filled with trypsin-containing sol-gels. This work provides a foundation for the microfabrication of functional protein chips using sol-gel processes. (C) 2001 John Wiley & Sons, Inc
Anarsia paraisogona Park & Ponomarenko 1996
No full text3. Anarsia paraisogona Park & Ponomarenko, 1996 (Figs. 3, 24, 43, 43 a) Anarsia paraisogona Park & Ponomarenko, 1996: 43; Ponomarenko, 2009: 348. TL: Thailand (North). The holotype is in BMNH. Diagnosis. Adult (Figs. 3, 24): Wingspan, 11 –11.5 mm. The species is superficially similar to A. isogona Meyrick, with a large subtriangular costal patch on the forewing transversally reaching about 3 / 5 towards dorsum with truncated lower margin, but can be distinguished by having a long expansible hair pencil on underside of the forewing. The male genitalia are quite different from each other as shown in the figures (Figs. 42 and 43). The male genitalia are very similar to those of A. acrotoma Meyrick, but can be distinguished by the right valva with more expanded distal half and more slender ventral process, which is longer than 1 / 2 the length of the right valva. The hindwing is grayish, with anterior expansion of costa well-developed to beyond middle; the venation is similar to that of A. isogona, with M 2 close to M 3 basally, M 3 and CuA 1 connate. Male genitalia (Figs. 43, 43 a): Uncus relatively long, hook-shaped apically. Tegumen longer than valva, expanded on lateral margin medially, narrower towards apex. Left valve ovate, inflated at base, with membranous flap on surface basally and a strongly curved process arising from near base, with round apex. Right valva relatively narrow, slightly dilated at base and broadened beyond middle, with a long, heavily sclerotized process before middle. Phallus arched, heavily ankylosed with juxta and vinculum at basal 1 / 4. Material examined. VIETNAM: 1 ♂, Vinh Phuc Prov., Tam Dao Nat. Park, 9 vii 2003 (KT Park, & Kim), gen. slide no. CIS- 6416; 1 ♂, same locality, 30 vii 2006 (Park, Chae, & Cuong); 2 ♂, 1 ♀, Nhin Binh Prov., Cuc Phuong Park, 750m, 30 vii 2006 (Park, Kim, & Kang), gen. slide no. CIS- 6427, - 6432. Distribution. Vietnam (new record; Vinh Phuc Prov.), Thailand (North). Remarks. In the original description of the species by Park and Ponomarenko (1995), it was erroneously described that the forewing lacks a long hairpencil on the underside of the forewing, but we here confirm that the species has a well-developed hairpencil.Published as part of Bae, Yang-Seop, Shin, Young-Min, Na, Sol-Moon & Park, Kyu-Tek, 2016, The genus Anarsia in Cambodia and the Northern Vietnam (Lepidoptera, Gelechiidae), with descriptions of ten new species and a catalogue of the genus in the Central-East Asia, pp. 227-252 in Zootaxa 4061 (3) on pages 230-231, DOI: 10.11646/zootaxa.4061.3.2, http://zenodo.org/record/26696
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