35,116 research outputs found
One-count memory circuit prevents machine mode interaction
One-count memory logic circuit used with electromechanical counter-printer machines operates in either count or print mode. The circuit advances the counter when the machine is in the count mode and provides storage for the count pulse when the machine is in the print mode
THE EFFECT OF TITLE I OF THE 1949 FEDERAL HOUSING ACT ON NEW YORK CITY COOPERATIVE AND CONDOMINIUM CONVERSION PLANS
In 1985, three Manhattan housing projects were in litigation to convert the units from rental to condominiums or cooperative ownership. However, each project\u27s redevelopment agreement, consistent with Title I of the 1949 Federal Housing Act, required that no change be made without consent of the City Planning Commission and the Board of Estimates of the City. This Note analyzes whether the conversion of rental units built under Title I to ownership units constitutes a change as interpreted by the New York courts. The interpretation of the term change under the Title I redevelopment agreements will be analyzed from both the City of New York\u27s and the private developer\u27s views. In addition, the legislative purposes behind Title I\u27s enactment will be examined from the perspectives of both the City of New York and the private developer. Finally, the current status of Title I will be discussed. This Note concludes that a change, for purposes of New York City redevelopment agreements drafted pursuant to Title I, refers only to land use and density and does not relate to the form of ownership. Therefore, city approval should not be required for a Title I building to convert to condominium or cooperative status
THE CREATIVE RATIONALITY AS A KEY DRIVER FOR ENHANCING INNOVATION CAPABILITY
Several recent works point out that design is one of the main driver of innovation. Therefore, it is interesting to analyze how design contributes to these last process. The point of view we present in this communication assumes that design is based on a specific rational we called creative rationality. This paper aims at presenting its theoretical roots. Creative rationality derives from Vico's notion of Ingenium. Creative rationality explains the creation of new artifacts and knowledge by knoting in a ingenious way scattered knowledge. It depends on several cognitive, individual and social variables one can identify, measure, and combine in a unified model.Design, creativity, innovation, creative rationality.
Modeling the hydrolysis of perfluorinated compounds containing carboxylic and phosphoric acid ester functions, alkyl iodides, and sulfonamide groups
Temperature dependent rate constants were estimated for the acid- and base-catalyzed and neutral hydrolysis reactions of perfluorinated telomer acrylates (FTAcrs) and phosphate esters (FTPEs), and the SN1 and SN2 hydrolysis reactions of fluorotelomer iodides (FTIs). Under some environmental conditions, hydrolysis of monomeric FTAcrs could be rapid (half-lives of several years in marine systems and as low as several days in some landfills) and represent a dominant portion of their overall degradation. Abiotic hydrolysis of monomeric FTAcrs may be a significant contributor to current environmental loadings of fluorotelomer alcohols (FTOHs) and perfluoroalkyl carboxylic acids (PFCAs). Polymeric FTAcrs are expected to be hydrolyzed more slowly, with estimated half-lives in soil and natural waters ranging between several centuries to several millenia absent additional surface area limitations on reactivity. Poor agreement was found between the limited experimental data on FTPE hydrolysis and computational estimates, requiring more detailed experimental data before any further modeling can occur on these compounds or their perfluoroalkyl sulfonamidoethanol phosphate ester (PFSamPE) analogs. FTIs are expected to have hydrolytic half-lives of about 130 days in most natural waters, suggesting they may be contributing to substantial FTOH and PFCA inputs in aquatic systems. Perfluoroalkyl sulfonamides (PFSams) appear unlikely to undergo abiotic hydrolysis at the S-N, C-S, or N-C linkages under environmentally relevant conditions, although potentially facile S-N hydrolysis via intramolecular catalysis by ethanol and acetic acid amide substituents warrants further investigation
Semiempirical, Hartree-Fock, density functional, and second order Moller-Plesset perturbation theory methods do not accurately predict ionization energies and electron affinities of short- through long-chain [n]acenes
Vertical, well-to-well, and adiabatic ionization energies (IEs) and electron affinities (EAs) were calculated for the n=1-10 [n]acenes using a wide range of semiempirical, Hartree-Fock, density functional, and second order Moller-Plesset perturbation theory model chemistries. None of the model chemistries examined were able to accurately predict the IEs or EAs for both short- through mid-length [n]acenes, as well as for extrapolations to the polymeric limit, when compared to available experimental and benchmark theoretical data. Provided a minimal basis set size is employed, basis set effects on predicted IEs and EAs are not significant relative to the choice of model chemistry. The poor IE/EA prediction performance for the parent [n]acenes likely extends to their substituted derivatives and heteroatom substituted analogs. Consequently, caution should be exercised in the application of non-high level calculations for estimating the IE/EA of these important classes of materials
Estimated carboxylic acid ester hydrolysis rate constants for food and beverage aroma compounds
Aroma compounds in the Flavornet database were screened for potentially hydrolyzable carboxylic acid ester functionalities. Of the 738 aroma compounds listed in this database, 140 molecules contain carboxylic acid ester groups that may be amenable to hydrolysis in various food and beverage products. Acid- (k~A~) and base- (k~B~) catalyzed and neutral (k~N~) hydrolysis rate constants in pure water at 25°C were estimated for these aroma compounds. Where available, good agreement between theoretical and experimental hydrolytic half-lives was obtained at various pH values. Wide ranges and broad frequency distributions for k~A~, k~B~, and k~N~ are expected among the various hydrolyzable aroma compounds, with estimated k~A~ ranging from 3.7×10^-8^ to 4.7×10^-4^ M^-1^ s^-1^, estimated k~B~ ranging from 4.3×10^-4^ to 43 M^-1^ s^-1^, and estimated k~N~ ranging from 4.2×10^-17^ to 7.6×10^-9^ M^-1^ s^-1^. The resulting hydrolytic half-lives also range widely, from 10 days to 370 years at pH 2.8, 18 days to 4,900 years at pH 4.0, 1.8 days to 470 years at pH 7.0, and 26 minutes to 5.1 years at pH 9.0. The findings presented herein attest to the importance of considering abiotic hydrolysis and matrix pH when modeling the evolution of sensory characteristics for foods and beverages with carboxylic acid ester based aroma compounds
Absence of historical temporal trends in monthly, seasonal, and annual streamflows for the Okanagan and Similkameen Rivers in south-central British Columbia, Canada
Potential historical temporal trends in monthly, seasonal, and annual mean, minimum, and maximum streamflows and date of the spring freshet runoff peak were investigated for the Okanagan and Similkameen Rivers in south-central British Columbia, Canada. There appears to be no compelling evidence that streamflow patterns in the Okanagan and Similkameen Rivers have changed over the available hydrometric record, nor does there appear to be evidence that future changes in streamflow patterns are imminent or likely
Historical temporal trends in groundwater levels from British Columbia, Canada
A time trend study of groundwater monitoring well levels was conducted in British Columbia, Canada. Trend data was available for a total of 210 groundwater monitoring well stations throughout the province with end-of-month water levels over the period of record. Significant temporal trends in groundwater levels were found at 67 stations (40.4% of all stations amenable to statistical examination, and 31.9% of all available stations). Of these 67 stations, 10 had increasing groundwater level trends and the remaining 57 had declining groundwater level trends. Thus, 34.3% of stations with a sufficiently long time series for analysis displayed declining groundwater level trends, while 6.0% have increasing trends, and 59.6% of these stations appear to have no significant temporal variation in groundwater levels. Geographic distinctions in groundwater level time trends are difficult to make owing to the unbalanced distribution of monitoring sites throughout the province. Based on percentages of total stations with a sufficiently long monitoring record for statistical analysis, it appears that the semi-arid Thompson/Nicola and Okanagan zones of British Columbia are most likely to have declining groundwater levels. Overall, a substantial proportion of groundwater monitoring wells in British Columbia - which have been operated with varying record lengths dating from recent installations to sites with records back to the 1950s - are exhibiting declining levels. At a significant number of other sites in the monitoring network, records are too short and/or poorly populated to facilitate statistical analysis
Gas phase enthalpies of formation, isomerization, and disproportionation of mono- through tetra-substituted tetrahedranes: A G4MP2/G4 theoretical study
Gas phase (298.15 K, 1 atm) enthalpies of formation (Δ~f~H°~(g)~), enthalpies of disproportionation to two corresponding acetylene molecules (Δ~rxn~H°~(g),Td→acet~), and enthalpies of isomerization from a tetrahedrane geometry to a 1,3-cyclobutadiene structure (Δ~isom~H°~(g),Td→CBD~) were calculated for the mono- through tetra-substituted hydro, fluoro, chloro, bromo, methyl, ethynyl, and cyano carbon tetrahedrane derivatives at the G4MP2 and G4 levels of theory. All derivatives have endothermic Δ~f~H°~(g)~ indicative of the cage strain in these systems. In all cases, Δ~rxn~H°~(g),Td→acet~ and Δ~isom~H°~(g),Td→CBD~ are predicted to be substantially exothermic. High quality linear regression fits within a homologous series were obtained between the number of substituents and the G4MP2/G4 estimated Δ~f~H°~(g)~. Via calculations on lower homolog members, this strategy was employed to allow extrapolated G4 and/or G4MP2 Δ~f~H°~(g)~ (as well as some Δ~rxn~H°~(g),Td→acet~ and Δ~isom~H°~(g),Td→CBD~) to be obtained for the mono- through tetra-substituted t-butyl, trifluoromethyl, and trimethylsilyl carbon tetrahedrane derivatives
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