bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Redox Properties of Crowded Triarylphosphines Carrying a Nitroxide Radical and Related Compounds
Authors: Sasaki Shigeru , Kato Kiyotoshi , Yoshifuji Masaaki 
Published: September 2007

Abstract
Crowded triarylphosphines carrying a nitroxide radical were synthesized to investigate intramolecular interaction between the crowded triarylphosphine redox centers and a neutral radical. A crowded triarylphosphine carrying a bromoaryl group was developed as a key synthetic intermediate. Lithiation of the (bromoaryl)phosphine, followed by reaction with 2-methyl-2-nitrosopropane, afforded a crowded triarylphosphine carrying a nitroxide after aerobic oxidation. Similar procedure using isoamyl nitrite (isoamyl = 3-methylbutyl) gave nitroxide and azobenzene derivatives with two crowded triarylphosphine moieties. The azobenzene derivative was alternatively prepared by photolysis of the corresponding (azidoaryl)phosphine. EPR spectra of the nitroxide radicals showed hyperfine couplings with 31P nuclei, which were larger than previously reported phosphinoaryl nitroxide radicals. Cyclic voltammograms of the newly synthesized triarylphosphines showed reversible redox waves corresponding to the phosphorus redox centers. The two triarylphosphine moieties connected by a nitroxide linkage showed a reversible two-step oxidation reflecting considerable interaction between the phosphorus redox sites across the nitroxide linkage. Oxidation of the crowded triarylphosphines carrying a nitroxide and photolysis of the chemically oxidized (azidoaryl)phosphine was studied by EPR spectroscopy.
Patterned Immobilization of Unprotected Carbohydrates on an Aminooxy Polymer-Grafted Solid Surface
Authors: Kamitani Ryosuke , Niikura Kenichi , Onodera Tomohiro , Iwasaki Norimasa , Shimaoka Hideyuki , Ijiro Kuniharu 
Published: September 2007

Abstract
We describe a graft-type modification of a solid surface to be able to immobilize unprotected carbohydrates with a desired pattern. Water soluble carbohydrate-trapping polymers were grown from a solid surface through surface-initiated polymerization. The polymerization of an N-tert-butonyloxycarbonyl (N-Boc)-protected aminooxy monomer 3 was carried out from the immobilized initiator on silicon or glass surfaces. The N-Boc protecting group was then removed in an acidic solution to generate an aminooxy group, which reacts with free carbohydrates through oxime bonds on immersion of the plate in a carbohydrate solution. Sugar attachment on the surface polymer was confirmed by using infrared reflection absorption spectroscopy (IR-RAS) and fluorescent images after sugar-specific binding of fluorescein-labeled lectin proteins. The polymer was also grafted in a desired pattern by partial UV-irradiation over a photomask, giving a new material to create carbohydrates arrays.
Novel Formation of 2-Arylquinolines and 1,3-Benzoxazines from 2-(1-Alkenyl)acylanilides and Active Halogens
Authors: Okuma Kentaro , Yasuda Takumi , Shioji Kosei , Yokomori Yoshinobu 
Published: September 2007

Abstract
2-Arylquinolines 1 were obtained in good yields by reacting iodine or NIS with 2-aminochalcones 2, which were easily synthesized by the Claisen–Schmidt reaction from 2-nitrobenzaldehyde and acetophenones. The reaction of iodine with 2-isopropenylacetanilide (3a), followed by the addition of aq. NaHCO3, afforded 4-iodomethyl-2,4-dimethyl-4H-3,1-benzoxazine (6a), of which the structure has previously been reported to be 1-acetyl-2-iodomethyl-2-methyl-1,2-dihydrobenzazete (4a) or 1-acetyl-3-iodo-3-methylindoline (5a). The reaction mechanism is discussed.
Reaction Behavior of Secondary Alcohols in Supercritical Water
Authors: Wang Pengyu , Kojima Hiroyuki , Kobiro Kazuya , Nakahara Koichi , Arita Toshihiko , Kajimoto Okitsugu 
Published: September 2007

Abstract
Benzhydrol and benzoin, which have two benzene subunits, a secondary hydroxy group, and no hydrogen atom on the β-position of the hydroxy group, were treated in supercritical water in the absence of an oxidizing agent or a catalyst. Water played a key role in the product distributions in these reactions. Each reaction proceeded smoothly to give larger amounts of oxidation products, benzophenone (3) and benzil (6), as well as smaller amounts of reduction products, diphenylmethane (4) and benzyl phenyl ketone (7), respectively, in the presence of water, while the ratios of 3:4 and 6:7 were almost 1:1 in both cases in the absence of water. The best yield of benzophenone (63%) was achieved by the reaction of benzhydrol at 460 °C for 180 min in 0.35 g mL−1 water density in the SUS 316 reactor. Hydrogen gas evolution was observed in the reaction of benzhydrol in a quartz tubular reactor.
Direct Observation of the Effect of Sodium Dodecyl Sulfate (SDS) on the HCFC-22 Hydrate Formation in a Static Mixer
Authors: Tajima Hideo , Nakajima Yosuke , Otomo Junichiro , Nagamoto Hidetoshi , Yamasaki Akihiro , Kiyono Fumio 
Published: September 2007

Abstract
Direct observation of the formation behavior of HCFC-22 hydrate in a Kenics type static mixer was conducted focusing on the effect of an addition of a surfactant, sodium dodecyl sulfate (SDS). The formation pattern of the hydrate was changed by the SDS addition from “slurry” to “plug,” and a continuous cycle of hydrate film formation and bubble escape was observed. The hydrate formation rate was increased about 10-fold by the addition of SDS (1000 ppm).
Photoinduced Sulfur Desorption from Platinum Nanoparticles Loaded on Titanium Dioxide
Authors: Miyazaki Satoshi , Kiyonaga Tomokazu , Kawahara Tetsuro , Tada Hiroaki 
Published: September 2007

Abstract
Photodeposition followed by postheating under different conditions yielded Pt particles on TiO2 in a highly dispersed state with a mean size (d) ranging from 1.1 to 9.2 nm (Pt/TiO2). Adsorption experiments of elemental sulfur (S8) on Pt/TiO2 showed that S is almost selectively adsorbed on the Pt surfaces independently of d (S–Pt/TiO2) and that the amount of S adsorbed per unit Pt surface area increases as the d value increases. Light irradiation (λex&gt;300 nm) to S–Pt/TiO2 in water led to S-desorption, of which rate increases with increasing d in the size range.
Fabrication of a Self-assembled Rotaxane Monolayer Consisting of a Viologen-functionalized Alkanethiol and α-Cyclodextrin Using Potential Sweep Method
Authors: Murakami Hiroto , Chifu Hiroko , Sagara Takamasa 
Published: September 2007

Abstract
A self-assembled monolayer of a rotaxane (rotaxane-SAM) consisting of N-(3,5-dimethoxybenzyl)-N′-6-mercaptohexylbipyridinium dibromide and α-cyclodextrin (α-CD) was successfully prepared using a potential sweep method by which unfavorable adsorption of α-CD and viologen dimer can be controlled.
A Novel Method for Fabrication of Unique Cobalt Nanostructures
Authors: Sun Shiyong , Li Jun , Xiong Ying , Yu Huijie , Tao Nan 
Published: September 2007

Abstract
In this article, a novel method has been developed for extracellular prepared of amorphous ring and chain cobalt nanostructures using Staphylococcus epidermidis in combination with PVP as template. The nanostructures consist of cobalt nanoparticles with the average particle size of 50 nm. The morphological difference between chain and ring nanostructures is determined by the interaction between PVP and bacteria. Extracellular prepation of nanostructures using bacteria as template opens up a new possibility to fabricate metal-based nanostructures in biological system.
Electrophoretic Deposition of a Thick Film of Layered Manganese Oxide
Authors: Zhang Xiong , Yang Wensheng 
Published: September 2007

Abstract
Delamination of layered manganese oxide into colloidal nanosheets occurred when manganese oxide intercalated with tetramethylammonium ions was ultrasonically dispersed in acetonitrile organic solution. An oriented layered manganese oxide thick film with (00l) plane parallel to the substrate was obtained by electrophoretic deposition of negatively charged manganese oxide nanosheets on ITO-coated glass substrate.
Polyculture of Endangered Bonytails and Razorback Suckers in Recirculated Water
Authors: Henne James P , Romero Matthew M , Carmichael Gary J 
Published: September 2007

Abstract
Bonytails Gila elegans and razorback suckers Xyrauchen texanus are imperiled fish species that are endemic to the Colorado River system in the southwestern United States. Captive propagation is a component of the recovery plan for each species, which are sometimes cultured together indoors in water reuse systems. A 3 × 2 factorial design was selected for examining the co-culture of two bonytail size-classes with razorback suckers at three densities (0, 2, or 5 razorback suckers/tank) for 120 d. There were four replicates of the design. Tank cleaning effort, measured as the number of required siphoning events per replicate (432-L tank), was significantly lower in tanks containing razorback suckers and bonytails (polyculture) relative to those without razorback suckers (monoculture). Survival was high, averaging 100% for razorback suckers and 96% for bonytails, but bonytail survival was significantly (P &lt; 0.05) lower for small bonytails cultured with 2 razorback suckers/tank relative to all other treatments. Razorback sucker density did not significantly affect the relative growth rate, specific growth rate, or final size (total length and weight) of either bonytail size-class but did result in significantly greater growth rates and final weight for razorback suckers at 2 fish/tank than at 5 fish/tank. Relative and specific growth rates were significantly greater for small bonytails (0.90% and 0.59%, respectively) than for large bonytails (0.31% and 0.26%, respectively). Bonytail size did not significantly affect razorback sucker growth rate or final size. Polyculture of these two fishes can increase culture efficiency and reduce the need for siphoning waste from culture tanks, a labor-intensive practice that is potentially stressful to the fish. Co-culture of bonytails and razorback suckers in recirculated water is a beneficial husbandry practice available to resource managers.
Alternatives to Freeze-Dried Krill in the Feed Training Phase of Largemouth Bass
Authors: Skudlarek Nicholas A , Cochran Nathan J , Larimore Mike , Marple Steve , Coyle Shawn , Tidwell James H 
Published: September 2007

Abstract
Fry of largemouth bass Micropterus salmoides are typically pond reared on natural foods until they reach approximately 4–6 cm. Fish that are to be raised on pellets are typically feed trained in tanks using freeze-dried krill (FDK), which is gradually replaced with prepared diet. The cost of FDK (retail &gt;US$40 per kg) can be a significant expense in the feed training phase. An experiment was conducted to determine whether FDK could be eliminated by simple diet amendment. The largemouth bass fingerlings (mean weight ± SD = 2.2 ± 0.3 g) were stocked in 190-L tanks at 150 fish/tank. Four treatments with four replicates each were compared: (1) fingerlings were initially fed FDK and then were gradually weaned to a commercial pellet (1.5-mm floating trout feed; control [CTL], current practice); (2) fish were offered only the dry commercial pellet throughout (DRY); (3) commercial pellets were moistened with water before use (MST); and (4) commercial pellets were top-dressed with menhaden fish oil at 10% of diet by weight initially and at a gradually reduced percentage over time (OIL). After 18 d, there was no significant difference (P &gt; 0.05) in the average weights of fish. However, in terms of percentage of fish that were successfully habituated to the final dry pellets, the DRY treatment resulted in a significantly lower (P &lt; 0.05) success rate (82%) than other treatments. Training success was not significantly different (P &gt; 0.05) among the CTL (98%), MST (93%), and OIL (92%) treatments. The best diet for feed training of largemouth bass will vary depending on the cost and availability of FDK and the economic importance of production maximization.
Preliminary Pond Evaluation of a Natural-Based Algicide for Managing Musty Off-Flavor in Channel Catfish Aquaculture
Authors: Schrader Kevin K , Tucker Craig S , Mischke Charles C 
Published: September 2007

Abstract
Environmentally derived “off-flavors” such as “earthy” and “musty” in cultured channel catfish Ictalurus punctatus are attributed to the presence of certain species of cyanobacteria (blue-green algae) in ponds. The musty off-flavor is caused by absorption of the metabolite 2-methylisoborneol (MIB) into channel catfish flesh. Most channel catfish producers manage off-flavor episodes by the application of algicides; however, these algicides have high environmental persistence and broad-spectrum toxicity. Recent research has discovered several natural and natural-based quinones that are effective and selective in reducing the abundance of the MIB-producing cyanobacterium Planktothrix perornata. In this study, efficacy testing of one of these quinones, anthraquinone-59, in a channel catfish pond found that it is effective in reducing the abundance of P. perornata and subsequently lowering the MIB levels in channel catfish.
Postrelease Survival of Hatchery-Reared Coho Salmon Juveniles Fed Low-Phosphorus and Other Diets
Authors: Tipping Jack M , Shearer Karl D 
Published: September 2007

Abstract
Three consecutive year-classes of coho salmon Oncorhynchus kisutch (initial weight, ∼13 g) were adipose fin-clipped, coded-wire-tagged, and divided into two groups and fed either a low-phosphorus (0.82% P) or a standard diet (1.26% P) from October until release in April (final weight, ∼28 g). Each treatment group consisted of two raceways of 20,000 fish. The mean lengths and condition factors of fish at release were generally similar, as were feed conversion rates. Whole-body P levels were similar at release in all groups (0.41–0.44%; wet basis). Percent retention of P was significantly greater for fish fed the low-P diet than for those fed the standard diet in 2 of 3 years, and P discharges were reduced by a mean of 55.3% with the low-P diet. Adult survival was similar for both groups of fish, ranging from 3.0% to 5.8%. Although no measurement was made of the availability of P, the total dietary P level (&gt;0.77%) in the low-P diets was sufficient for juvenile coho salmon during the freshwater phase of rearing.
An Attempt to Rehabilitate a Collapsed Brook Trout Population by Introducing F1 Splake to Control Yellow Perch
Authors: Rumsey Charles R. , Jones Nicholas E. , Banks Hugh H. 
Published: September 2007

Abstract
Historically, brook trout Salvelinus fontinalis provided an outstanding sport fishery and lived sympatrically with yellow perch Perca flavescens in East Lake, a 30-ha water body in central Ontario. The fishery collapsed when lake access was improved and cottages were built around the shore in the early 1960s. Annual stocking of brook trout did not improve the brook trout fishery. During the 1980s it became apparent that yellow perch were abundant and small-bodied. Based on historical studies in similar ecosystems, we concluded that the perch were competing directly with, and possibly preying on, the juvenile brook trout. In this study we attempted to reduce the perch population by repeatedly stocking first-generation (F1) splake hybrids (female lake trout Salvelinus namaycush × male brook trout) over a 7-year period. We hypothesized that the splake would reduce the abundance of yellow perch, which in turn would allow the brook trout population to increase. Stock assessments during the study period (1990–1997) indicated that the yellow perch density declined more than 95% (from approximately 3,400 to approximately 130 individuals/ha). We argue that the splake caused this reduction because routinely stocked rainbow trout Oncorhynchus mykiss and brook trout had failed to reduce the number of yellow perch and the decline coincided with the splake stocking. In addition, concurrent diet analyses indicated that splake were considerably more piscivorous and much more likely to consume yellow perch than were rainbow trout and brook trout. Although the number of yellow perch was greatly reduced, the brook trout population did not appear to increase; nor was there evidence of a decline in the absence of stocking during the manipulation. We propose the following reasons for the lack of a brook trout response: overharvesting, interspecific competition among salmonids or from residual forage species, the brevity of the study period, and genetic introgression with hatchery brook trout.
Estimating Sampling Effort for Biomonitoring of Nearshore Fish Communities in Small Central Minnesota Lakes
Authors: Drake Melissa T. 
Published: September 2007

Abstract
I estimated the sampling effort required to sufficiently describe the species richness and composition of fish inhabiting the nearshore (wadeable) zone of lakes and compared 10 species richness estimators in 56 similarly sized (small) central Minnesota lakes. A systematic sampling design was employed wherein 10 stations were equally spaced around each lake and the first station was selected randomly. Sampling methods consisted of a combination of backpack electrofishing and shoreline seining. Using sample-based rarefaction curves, eight sampling stations produced at least 90% of the sampled species in 96% of the study lakes. Less sampling effort (four to six stations) was needed to describe the composition of the nearshore fish assemblage, as measured by similarity of species composition or species relative abundances in cumulative samples. The effort needed to sufficiently describe nearshore species richness was not related to observed species richness but was negatively correlated with species evenness among sampling stations. Estimates of total nearshore species richness were made using an asymptotic accumulation function, a log-linear model, two abundance-based nonparametric estimators, and six incidence-based nonparametric estimators. All estimates of total species richness were correlated with observed species richness. Estimated total species richness exceeded observed species richness; however, this difference was smallest when species evenness was high. Nonparametric methods produced unrealistically high richness estimates if many species were encountered infrequently. Observed richness varied among lakes and was positively related to measures of lake integrity. Observed richness, estimated total richness, and sufficient effort levels were similar for lakes sampled twice, suggesting that both the sampling method and estimated levels of sufficient effort were robust. The results of this study suggest that more intensive nearshore sampling with seines and backpack electrofishing will be of limited benefit unless the detection of rare species is the major goal of sampling; alternative sampling gears may be needed to detect new species.
Distribution of Nonnative Aquatic Vertebrates in Western U.S. Streams and Rivers
Authors: Lomnicky Gregg A. , Whittier Thomas R. , Hughes Robert M. , Peck David V. 
Published: September 2007

Abstract
Nonnative aquatic vertebrates have been widely introduced across the western United States. We analyzed data from the Environmental Monitoring and Assessment Program's western pilot study to determine the occurrence of nonnative fish and amphibians and the proportion of stream length they occupied in streams of 12 conterminous western states. A total of 1,361 sites (including both probability sites and candidate reference sites) were sampled from 2000 to 2004. Of these, 711 probability sites had sufficient sampling effort and vertebrates present, representing a total assessed stream length of 213,600 km. Native and nonnative species numbers and proportionate abundances based on this stream length are reported for the entire study area, for three large-scale ecoregions (Mountains, Xeric, and Plains), and for each state in the survey area. Sites with insufficient sampling effort or collection permit restrictions or in which no vertebrates were collected could not be assessed and represented an additional 90,000 km of stream length. An estimated 52 ± 4% (mean and 95% confidence interval) of the assessed stream length contained nonnative vertebrates. Nonnatives represented more than 50% of the individuals in 22 ± 3% of the assessed stream length. Nonnative vertebrates were present in 59 ± 10% of the assessed length represented by fourth-order rivers and in 83 ± 6% of the assessed length represented by fifth-order and larger rivers. From 30 to 33 nonnative species were found in each of the three ecoregions. Brook trout Salvelinus fontinalis, brown trout Salmo trutta, and rainbow trout Oncorhynchus mykiss were the most common nonnative aquatic vertebrates found in the study area based on the proportion of assessed stream length occupied. Of the 12 states surveyed, California accounted for the greatest number of nonnative taxa we collected (26) and Idaho the fewest (4).
Use of Unsectioned Dorsal Spines for Estimating Walleye Ages
Authors: Logsdon Dale E. 
Published: September 2007

Abstract
Dorsal spines may be a suitable structure for aging walleyes Sander vitreus when the otoliths are unavailable due to live release of the catch, but the specialized equipment and additional time necessary to remove and mount a readable cross section can discourage their use. I evaluated a simple method of obtaining age estimates from unsectioned dorsal spines. The basal end of each dorsal spine was sanded smooth and viewed under a dissecting microscope with side illumination. For Red Lake, Minnesota, walleyes, where consensus otolith ages by two experienced readers indicated that most fish were younger than age 7, reader agreement rates (95%) and precision (mean coefficient of variation (CV) = 0.95%) of dorsal spine estimates were relatively high. Age estimates by individual readers inspecting spines generally agreed with consensus otolith ages (≥95%). Reader agreement rates (70%) and precision (mean CV = 2.71%) were much lower for a sample of walleyes collected from Mille Lacs Lake, Minnesota, where 94% of consensus otolith ages were greater than age 6. Furthermore, spine-based age estimates for Mille Lacs Lake walleyes exhibited relatively poor agreement with consensus otolith ages (≤40%); however, most of the discrepancies were noted for individuals of consensus otolith age 7 or more, and consistent underestimation of ages did not occur until age 13. Based on these findings, unsectioned dorsal spines offered a reasonably precise, nonlethal, and simple approach for replicating consensus otolith ages for walleyes younger than age 7. Although otoliths may still be necessary to estimate the ages of older individuals within a sample, use of unsectioned dorsal spines could allow biologists to sacrifice fewer walleyes while closely replicating otolith-based estimates of population age structure.
Spatial distribution of zooplankton in a cascade system of Pomeranian dam reservoirs (Hajka, Rosnowo), northern Poland
Authors: Pociecha Agnieszka , Heese Tomasz 
Published: September 2007

Abstract
The structure of the zooplankton community and its spatial distribution were examined in two stratified rheolimnic Pomeranian reservoirs, Rosnowski (7 sampling sites) and Hajka (4 sampling sites), in July 1999. These reservoirs are part of the cascade system situated on the Radew River in northern Poland. In the Rosnowski reservoir 34 species of zooplankton were identified and in Hajka, 32. The two dominant species of rotifers in both reservoirs were Keratella cochlearis f. tecta and Polyarthra vulgaris. The dominant copepod and cladoceran species in both reservoirs were Mesocyclops leuckarti and Daphnia cucullata, respectively. Along the longitudinal axis of both reservoirs, rotifers were the dominant group at all sampling sites, except for the hypolimnion layer in both reservoirs and the metalimnion layer in Hajka reservoir at site H1. This initial study was undertaken in order to determine the spatial distribution of rotifer, copepod and cladoceran communities in riverine reservoirs built in the cascade system.