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1

Bioactive compounds from selected plants used in the XVI century mexican traditional medicine  

Microsoft Academic Search

Mexican ethnobotanical documents from the XVI century have inspired the search of plant bioactive compounds. These treatises were written by Native American and Spaniard naturalists after the Spanish conquest of México in 1521, and contain painstaking descriptions of more than 3,000 plants. The present and ancient native medical applications of selected plants quoted in these ethnohistorical sources are revisited and

E. BÉjar; R. Reyes-Chilpa; M. JimÉnez-Estrada

2000-01-01

2

Thermochemistry of uranium compounds: XVI, Calorimetric determination of the standard molar enthalpy of formation at 298.15 K, low-temperature heat capacity, and high-temperature enthalpy increments of UO{sub 2}(OH){sub 2} {center_dot} H{sub 2}O (schoepite)  

SciTech Connect

Three precise calorimetric methods, viz., low-temperature adiabatic, high-temperatuare drop, and solution-reaction, have been used to determine as a function of temperature the key chemical thermodynamic properties of a pure sample of schoepite, UO{sub 2}(OH){sub 2} {center_dot} H{sub 2}O. The following results have been obtained at the standard reference temperature T = 298.15 K:standard molar enthalpy of formation {Delta}/sub f/H/sub m/{sup 0}(T) = {minus}1825.4 +- 2.1 kJ mol/sup {minus}1/; molar heat capacity C/sub p,m/{sup 0}(T) = 172.07 +- 0.34 JK/sup {minus}1/; and the standard molar entropy S/sub m/{sup 0}(T) = 188.54 +- 0.38 JK/sup {minus}1/ mol/sup {minus}1/. The molar enthalpy increments relative to 298.15 K and the molar heat capacity are given by the polynomials: {H{sub m}{sup 0}(T) {minus} H{sub m}{sup 0}(298.15 K)}/(J mol/sup {minus}1/) = {minus}38209.0 + 84.2375 (T/K) + 0.1472958 (T/K){sup 2} and C/sub p,m/{sup 0}(T)/(JK/sup {minus}1/ mol/sup {minus}1/) = 84.238 + 0.294592 (T/K), where 298.15 K < T < 400 K. The present result for {Delta}/sup f/H/sub m/{sup 0} at 298.15 K has been combined with three other closely-agreeing values from the literature to give a recommended weighted mean {Delta}/sub f/H/sub m/{sup 0} = {minus}1826.4 +- 1.7 kJ mol/sup {minus}1/, from which is calculated the standard Gibbs energy of formation {Delta}/sub f/G/sub m/{sup 0} = {minus}1637.0 +- 1.7 kJ mol/sup {minus}1/ at 298.15 K. Complete thermodynamic properties of schoepite are tabulated from 298.15 to 423.15 K. 19 refs., 6 tabs.

Tasker, I.R.; O`Hare, P.A.G.; Lewis, B.M.; Johnson, G.K.; Cordfunke, E.H.P.

1987-08-01

3

Calorimetric investigation of the solid compounds of the Au–Pb system  

Microsoft Academic Search

The three intermediate compounds of the Au–Pb system were synthesised by melting the pure components in suitable proportions and annealing at a temperature just below their melting point. Their structural states were verified by X-ray studies.The enthalpy of formation of the compounds was measured by dissolution calorimetry (drop method) at 650K in liquid lead using a high temperature Tian–Calvet calorimeter.

A. Bouhajib; A. Nadiri; A. Yacoubi; H. Bros; R. Castanet

1999-01-01

4

Calorimetric experiments on social insects  

Microsoft Academic Search

Direct calorimetric experiments on the social insects: honeybees, bumblebees and hornets are described as function of castes, age, number of animals in a group, temperature, sound generation, hibernation and influence of pheromones. Two honeybee subspecies, the European bee Apis mellifera carnica and the Egyptian bee Apis mellifera lamarckii, were compared calorimetrically in their energy metabolism which differed considerably in favour

Ingolf Lamprecht

1997-01-01

5

Calorimetric gas sensor  

DOEpatents

A combustible gas sensor that uses a resistively heated, noble metal-coated, micromachined polycrystalline Si filament to calorimetrically detect the presence and concentration of combustible gases. The filaments tested to date are 2 .mu.m thick.times.10 .mu.m wide.times.100, 250, 500, or 1000 .mu.m-long polycrystalline Si; some are overcoated with a 0.25 .mu.m-thick protective CVD Si.sub.3 N.sub.4 layer. A thin catalytic Pt film was deposited by CVD from the precursor Pt(acac).sub.2 onto microfilaments resistively heated to approximately 500.degree. C.; Pt deposits only on the hot filament. Using a constant-resistance-mode feedback circuit, Pt-coated filaments operating at ca. 300.degree. C. (35 mW input power) respond linearly, in terms of the change in supply current required to maintain constant resistance (temperature), to H.sub.2 concentrations between 100 ppm and 1% in an 80/20 N.sub.2 /O.sub.2 mixture. Other catalytic materials can also be used.

Ricco, Antonio J. (Albuquerque, NM); Hughes, Robert C. (Cedar Crest, NM); Smith, James H. (Albuquerque, NM); Moreno, Daniel J. (Albuquerque, NM); Manginell, Ronald P. (Albuquerque, NM); Senturia, Stephen D. (Brookline, MA); Huber, Robert J. (Bountiful, UT)

1998-01-01

6

Calorimetric gas sensor  

DOEpatents

A combustible gas sensor is described that uses a resistively heated, noble metal-coated, micromachined polycrystalline Si filament to calorimetrically detect the presence and concentration of combustible gases. The filaments tested to date are 2 {micro}m thick {times} 10{micro}m wide {times} 100, 250, 500, or 1000 {micro}m-long polycrystalline Si; some are overcoated with a 0.25 {micro}m-thick protective CVD Si{sub 3}N{sub 4} layer. A thin catalytic Pt film was deposited by CVD from the precursor Pt(acac){sub 2} onto microfilaments resistively heated to approximately 500 C; Pt deposits only on the hot filament. Using a constant-resistance-mode feedback circuit, Pt-coated filaments operating at ca. 300 C (35 mW input power) respond linearly, in terms of the change in supply current required to maintain constant resistance (temperature), to H{sub 2} concentrations between 100 ppm and 1% in an 80/20 N{sub 2}/O{sub 2} mixture. Other catalytic materials can also be used. 11 figs.

Ricco, A.J.; Hughes, R.C.; Smith, J.H.; Moreno, D.J.; Manginell, R.P.; Senturia, S.D.; Huber, R.J.

1998-11-10

7

PREFACE: Symmetries in Science XVI  

NASA Astrophysics Data System (ADS)

This volume of the proceedings ''Symmetries in Science XVI'' is dedicated to the memory of Miguel Lorente and Allan Solomon who both participated several times in these Symposia. We lost not only two great scientists and colleagues, but also two wonderful persons of high esteem whom we will always remember. Dieter Schuch, Michael Ramek There is a German saying ''all good things come in threes'' and ''Symmetries in Science XVI'', convened July 20–26, 2013 at the Mehrerau Monastery, was our third in the sequel of these symposia since taking it over from founder Bruno Gruber who instigated it in 1988 (then in Lochau). Not only the time seemed to have been perfect (one week of beautiful sunshine), but also the medley of participants could hardly have been better. This time, 34 scientists from 16 countries (more than half outside the European Union) came together to report and discuss their latest results in various fields of science, all related to symmetries. The now customary grouping of renowned experts and talented newcomers was very rewarding and stimulating for all. The informal, yet intense, discussions at ''Gasthof Lamm'' occurred (progressively later) each evening till well after midnight and finally till almost daybreak! However, prior to the opening ceremony and during the conference, respectively, we were informed that Miguel Lorente and Allan Solomon had recently passed away. Both attended the SIS Symposia several times and had many friends among present and former participants. Professor Peter Kramer, himself a long–standing participant and whose 80th birthday commemoration prevented him from attending SIS XVI, kindly agreed to write the obituary for Miguel Lorente. Professors Richard Kerner and Carol Penson (both also former attendees) penned, at very short notice, the tribute to Allan Solomon. The obituaries are included in these Proceedings and further tributes have been posted to our conference website. In 28 lectures and an evening poster–session, topics ranging from theoretical chemistry and molecular physics via fundamental problems in quantum theory to thermodynamics, nonlinear dynamics, soliton theory and finally cosmology, were examined and lively discussed. Nearly all the talks can also be viewed on the conference website. The majority of participants contributed to these Proceedings but some were unable to do so as their results were either previously submitted or published elsewhere. We refer to: · Quesne C 2013, J. Math. Phys. 54, 102102. · Spera M 2013, (Nankai Series in Pure, Applied Mathematics and Theoretical Physics): 11 Symmetries and Groups in Contemporary Physics: pp. 593–598 Proceedings of the XXIX International Colloquium on Group–Theoretical Methods in Physics Tianjin, China, 20 – 26 August 2012 (World Scientific, Singapore) · Snobl L and Winternitz P 2014, Classification and Identification of Lie Algebras, CRM Monograph Series 33 (Montreal) ISBN–10: 0–8218–4355–9, ISBN–13: 978–0–8218–4355–0 (http://www.ams.org/bookstore?fn=20&arg1=crmmseries&ikey=CRMM-33). Our personal thanks to Daniel and family! Endless support from the Schenk Family who, among other things, sponsored (yet again) the entire conference dinner (including wines and banquet hall) meant that some costs could be alleviated. We could therefore assist various colleagues from economically–weak countries, despite the lack of external funding. A financial deficit meant we would have had to forego the Conference Proceedings, published in previous years by IOP. After long deliberations, and with donations from Gerhard Berssenbrügge, Dr. Dr. Stephan Hauk and Dr. Volker Weisswange, this could be facilitated. We are very grateful to these private donors for their generous and wholehearted support. The staff of Collegium Mehrerau is also to be thanked for their hospitality. Finally, our sincere thanks to Yvette not only for her preparatory work and support during the conference, but also for her persistent interest and help in producing the Proceedings within a reasonable time. Dieter Schuc

2014-10-01

8

XVI Encontro de Economia da Regio Sul -ANPEC SUL 2013 XVI Encontro de Economia da Regio Sul  

E-print Network

XVI Encontro de Economia da Região Sul - ANPEC SUL 2013 1 XVI Encontro de Economia da Região Sul Programa de Pós Graduação em Desenvolvimento Econômico Curitiba - PR #12;XVI Encontro de Economia da Região/UFPR) Secretárias do PPGDE Aurea Koch Ivone Polo #12;XVI Encontro de Economia da Região Sul - ANPEC SUL 2013 3

Paraná, Universidade Federal do

9

Calorimetric assay of minor actinides  

SciTech Connect

This paper reviews the principles of calorimetric assay and evaluates its potential application to the minor actinides (U-232-4, Am-241, Am- 243, Cm-245, Np-237). We conclude that calorimetry and high- resolution gamma-ray isotopic analysis can be used for the assay of minor actinides by adapting existing methodologies for Pu/Am-241 mixtures. In some cases, mixtures of special nuclear materials and minor actinides may require the development of new methodologies that involve a combination of destructive and nondestructive assay techniques.

Rudy, C.; Bracken, D.; Cremers, T.; Foster, L.A.; Ensslin, N.

1996-12-31

10

Air Pollution XVI 247 Emissions of Nitrogen Dioxide from Modern  

E-print Network

Air Pollution XVI 247 Emissions of Nitrogen Dioxide from Modern Diesel Vehicles G.A. Bishop and D;Air Pollution XVI 248 The DPF is an extremely effective means to achieve particle reduction goals increase, are of concern to air pollution photochemistry because NO2 leads directly, through solar

Denver, University of

11

2008 Site environmental report xvi the environmental and Waste Management  

E-print Network

Group environmental restoration project Division information Services Division media & Communications2008 Site environmental report xvi DRAFT the environmental and Waste Management services Division Lagattolla not pictured) the environmental information Management services group (Back row, left to right

12

2007 Site environmental report xvi the environmental and Waste Management  

E-print Network

2007 Site environmental report xvi the environmental and Waste Management services Division field Division radiological Control Division lead chapter authors environmental and waste management services contributors environmental and waste management services division Arland Carsten, Consultant Mark Davis George

13

Gravimetric, dielectric and calorimetric methods for the detection of organic solvent vapours using poly(ether urethane) coatings  

Microsoft Academic Search

Cycloaliphatic poly(ether urethane) has been used as a sensitive layer for the detection of organic solvent vapours such as ketones, alcohols, amines, alkanes, aromatic compounds and chlorinated hydrocarbons with quartz microbalances (QMB), interdigital capacitors (IDC) and calorimetric transducers. The sensor signals are completely reversible and reproducible at room temperature. Using QMBs, even less than 10 ppm of nitrobenzene in air

R. Zhou; A. Hierlemann; U. Weimar; W. Göpel

1996-01-01

14

ARTICLE XVI PART I. The Workload of the Faculty  

E-print Network

75 ARTICLE XVI WORKLOAD PART I. The Workload of the Faculty The maximum teaching load for tenured and tenure-track faculty is 18 credit hours or equivalent contact hours as defined by the college workload as defined by the college workload committee for research-active faculty or faculty who submit a research

Massachusetts at Lowell, University of

15

Ultra-Responsive Thermal Sensors for the Detection of Explosives Using Calorimetric Spectroscopy (CalSpec)  

SciTech Connect

We have developed a novel chemical detection technique based on infrared micro-calorimetric spectroscopy that can be used to identify the presence of trace amounts of very low vapor pressure target compounds. Unlike numerous recently developed low-cost sensor approaches, the selectivity is derived from the unique differential temperature spectrum and does not require the questionable reliability of highly selective coatings to achieve the required specificity. This is accomplished by obtaining the infrared micro-calorimetric absorption spectrum of a small number of molecules absorbed on the surface of a thermal detector after illumination through a scanning monochromator. We have obtained infrared micro-calorimetric spectra for explosives such as TNT over the wavelength region 2.5 to 14.5 Mu-m. Thus both sophisticated and relatively crude explosive compounds and components are detectable with these ultra-sensitive thermal-mechanical micro-structures. In addition to the above mentioned spectroscopy technique and associated data, the development of these advanced thermal detectors is also presented in detail.

Datskos, P.G.; Datskou, I.; Marlar, T.A.; Rajic, S.

1999-04-05

16

Calorimetric thermobarometry of experimentally shocked quartz  

NASA Technical Reports Server (NTRS)

Structural damage in experimentally shock-metamorphosed, granular quartz is quantitatively measurable by differential scanning calorimetry (DSC). Shock-induced loss of crystallinity is witnessed by disappearance of the alpha/beta phase transformation and evolution of a broad endoenthalpic strain peak at 650-900 K. The strain-energy peak grows rapidly at less than 10 GPa but declines with increasing shock pressure; it approaches zero at 32 GPa where vitrification is extensive. Effects of grain size and post-shock thermal history must be better understood before calorimetric thermobarometry of naturally shocked samples becomes possible.

Ocker, Katherine D.; Gooding, James L.; Hoerz, Friedrich

1994-01-01

17

Calorimetric Studies at the New Hydrogen Energy Laboratory in Japan  

Microsoft Academic Search

Experiments using China Lake type calorimetric cells produced excess power in three out of three experiments and no excess power in three control studies. A detailed analysis is presented for two experiments using the China Lake cells. Anomalous thermistor signals in Cell A suggest the emission of electromagnetic radiation from the active palladium cathode. Experiments in Fleischmann-Pons type calorimetric cells

Melvin H. Miles

2000-01-01

18

NISTIR 5732 Calorimetric and Visual Measurements of R123  

E-print Network

of nucleate boiling were also investigated. The boiling was visually recorded with 16 mm high speed filmNISTIR 5732 Calorimetric and Visual Measurements of R123 Pool Boiling on Four Enhanced Surfaces #12;NISTIR 5732 Calorimetric and Visual Measurements of R123 Pool Boiling on Four Enhanced Surfaces

Oak Ridge National Laboratory

19

A calorimetric system for metabolic studies of newborn babies  

Microsoft Academic Search

Describes a closed circuit calorimetric system designed to determine the amount of energy required for synthesis of new tissue in a newborn baby. This amount can be estimated from the difference between indirect and calorimetric measurements. The system allows the simultaneous measurement of oxygen consumption, carbon dioxide production, evaporative water loss and heat loss through convection and radiation in newborn

H J Dane; W P J Holland; P J J Sauer; H K A Visser

1985-01-01

20

EDITORIAL: Special issue: CAMOP MOLEC XVI  

NASA Astrophysics Data System (ADS)

In this special issue of CAMOP/Physica Scripta we would like to present a picture of the state-of-the-art in the field of the dynamics of molecular systems. It contains a collection of papers submitted in association with the most recent MOLEC meeting (MOLEC XVI), which was held in September 2006 in Levico Terme (Italy) to celebrate the 30th anniversary of the MOLEC conference series. The series of biennial European Conferences on the Dynamics of Molecular Systems (MOLEC) started in 1976, when the first meeting was held in Trento (Italy). Successive conferences were organized in Brandbjerg Højskole (Denmark, 1978), Oxford (UK, 1980), Nijmegen (The Netherlands, 1982), Jerusalem (Israel, 1984), Aussois (France, 1986), Assisi (Italy, 1988), Bernkastel-Kues (Germany, 1990), Prague (Czech Republic, 1992), Salamanca (Spain, 1994), Nyborg Strand (Denmark, 1996), Bristol (UK, 1998), Jerusalem (Israel, 2000), Istanbul (Turkey, 2002) and Nunspeet (The Netherlands, 2004). This is the second time that Physica Scripta has hosted a special issue dedicated to MOLEC. The previous issue ( Physica Scripta (2006) 73 C1-C89) was edited by Steven Stolte and Harold Linnartz following the MOLEC 2004 conference. Following the philosophy of CAMOP, we have asked invited speakers to summarize important problems in their research area, with the objective of setting forth the current thinking of leading researchers in atomic, molecular and optical physics. This comprises discussions of open questions, important new applications, new theoretical and experimental approaches and also predictions of where the field is heading. In addition to being authoritative contributions of acknowledged experts, we hope that the papers also appeal to non-specialists as each work contains a clear and broad introduction and references to the accessible literature. The present special issue comprises 17 papers, which are arranged according to the following topics: theoretical and experimental studies of molecular collisions and chemically reactive systems (papers by Toennies, Cavalli et al, Varandas, Nyman, Allan et al, Liu et al, Boxford et al); cooling and alignment of molecular systems (papers by Kumarappan et al, van de Meerakker et al); photon-matter interactions, spectroscopy and photodissociation (papers by Fárník and Buck, Golan et al, Borghesani et al, Coreno et al); theory of complex systems (papers by Villarreal et al, Bodo et al, Yurtsever and Calvo). The final contribution concerns the dynamics of systems of biological relevance (paper by Denicke et al). The paper by Toennies, one of the founding fathers of the MOLEC conference and winner of the MOLEC award in 1996, presents a comprehensive account of the experimental developments in the field of low energy collisions over the last 30 years, and provides a short outlook on how the most recent cooling and ultra cooling techniques (helium droplets and electro-magnetic laser traps) could open up new perspectives in the field of chemical reaction dynamics. Cavalli et al present a theoretical interpretation of overlapping resonances in the reactive cross section for the benchmark reaction F + H2?HF + H, explained by the formation of a short-lived state located in the transition state region and of a van der Waals metastable state in the exit valley. The subject of accurate ab initio calculations for potential energy surfaces is addressed by Varandas in a paper describing suitable modelling strategies to obtain intermolecular potentials at near spectroscopic resolution. In the following paper, Nyman gives an overview of how thermal rate constants for polyatomic chemical reactions can be calculated from first principles: the reaction H2 + CH3?CH4 + H is used as an example and theoretical results are compared with experimental ones. The `uncharted territory' of collision dynamics at the gas-liquid interface is explored in the pioneering contribution by Allan et al, in which experimental results on the reactivity of O atoms with long chain liquid hydrocarbons are interpreted with the aid of molecular dynamic

Ascenzi, Daniela; Franceschi, Pietro; Tosi, Paolo

2007-09-01

21

Radiation beam calorimetric power measurement system  

DOEpatents

A radiation beam calorimetric power measurement system for measuring the average power of a beam such as a laser beam, including a calorimeter configured to operate over a wide range of coolant flow rates and being cooled by continuously flowing coolant for absorbing light from a laser beam to convert the laser beam energy into heat. The system further includes a flow meter for measuring the coolant flow in the calorimeter and a pair of thermistors for measuring the temperature difference between the coolant inputs and outputs to the calorimeter. The system also includes a microprocessor for processing the measured coolant flow rate and the measured temperature difference to determine the average power of the laser beam.

Baker, John (Livermore, CA); Collins, Leland F. (Pleasanton, CA); Kuklo, Thomas C. (Ripon, CA); Micali, James V. (Dublin, CA)

1992-01-01

22

Compound  

NASA Astrophysics Data System (ADS)

We have prepared Ce-doped polycrystalline AgSbTe2.01 compounds from high-purity elements by a melt-quench technique followed by spark plasma sintering, and their thermoelectric transport properties have been investigated in the temperature range of 300 K to 625 K. The actual concentration of Ce was much less than the initial composition, but roughly proportional to it. Small additions of Ce shifted the composition of the homogeneity range from the nearly ideal atomic ratio Ag:Sb:Te = 0.98:1.02:2.01 toward Sb rich (Ag poor), and led to the reemergence of Ag2Te impurity in AgSbTe2 compound. The Ce-doped samples possessed lower electrical conductivity compared with the undoped AgSbTe2.01 compound at room temperature, but the carrier mobility and effective mass were essentially constant, indicating intact band structure near the covalent band maximum upon Ce substitution for Sb. Due to the decrease of lattice vibration anharmonicity resulting from Ce substitution for Sb, the lattice conductivity of the Ce-doped samples was about 0.1 W m-1 K-1 higher than that of the AgSbTe2.01 sample, and the magnitude spanned the range from 0.30 W m-1 K-1 to 0.55 W m-1 K-1. A ZT of 1.20 was achieved at about 615 K for the AgSb0.99Ce0.01Te2.01 sample.

Du, B.; Li, H.; Tang, X.

2014-06-01

23

Intercultural Communication Studies XVI: 3 A Disease That "Has a Woman's Face": The Social Construction  

E-print Network

Intercultural Communication Studies XVI: 3 A Disease That "Has a Woman's Face": The Social of HIV infection because they #12;Intercultural Communication Studies XVI: 3 lack the power to determine be seen in some feminist research in communication which focuses on "how gender is constructed through

Kvasny, Lynette

24

compounds  

NASA Astrophysics Data System (ADS)

Size is the key factor of nanostructured materials, since all the structural, transport, electrical, magnetic and other physical properties can be tuned by this factor of materials. Only the condition is to choose appropriate inexpensive scale-processing method for material synthesis which offers good control over the stoichiometry, morphology and particle size distribution. Present communication deals with the studies on the sol-gel grown Y0.95Ca0.05MnO3 (YCMO) nanostructured compounds for their size-induced tuning of dielectric behavior. Structural studies reveal the single phasic nature with improved crystallite size with sintering temperature. Dielectric constant (real and imaginary) is found to increase with temperature and crystallite size/sintering temperature. High dielectric loss has been observed in the present system. Size dependent activation energy ( E a), obtained from modulus measurement, showing the increase in E a with crystallite size. The variation in various dielectric parameters and E a has been discussed in the light of crystallite size, crystallite boundaries, oxygen vacancies and charge carrier hopping.

Shah, N. A.

2014-10-01

25

The CALorimetric Electron Telescope, CALET, Mission  

NASA Astrophysics Data System (ADS)

We are developing the CALorimetric Electron Telescope, CALET, mission for the Japanese Experiment Module Exposed Facility, JEM-EF, of the International Space Station. Major scientific objectives are to search for nearby cosmic ray sources and dark matter by carrying out a precise measurement of the electrons in GeV 20 TeV and the gamma-rays in 20 MeV TeV. CALET has a unique capability to observe electrons and gamma-rays over 1 TeV since the hadron rejection power is more than 105 and the energy resolution better than a few percent over 100 GeV. The detector consists of an Imaging Calorimeter (IMC) with scintillating fiber belts and tungsten plates, a Total Absorption Calorimeter (TASC) with BGO logs, a Silicon Pixel Array (SIA) and a Scintillator Anti-Coincidence System (SACS). CALET has also a capability to measure protons and nuclei in 10 GeV 1000 TeV, and will have a function to monitor solar activity and gamma-ray bursts with additional instruments. The phase A study has started on a schedule of launch in 2013 by H-II Transfer Vehicle (HTV) for 5 years observation.

Torii, Shoji

26

Calorimetric Study of Diluted Spin Ice Materials  

NASA Astrophysics Data System (ADS)

Spin ice materials Dy2Ti2O7 and Ho2Ti2O7 have been the subject of ongoing interest for over ten years. The cooperative magnetic ground state can be mapped onto the proton disordered ground state in water ice, and its residual entropy follows the same Pauling's estimate. Interestingly it was found in a previous study that, upon dilution of the magnetic rare earth ions Dy^3+ and Ho^3+ by non-magnetic substitutes Y^3+, the residual entropy depends non-monotonically on the dilution level. In this work we investigate through Monte Carlo simulations microscopic models to account quantitatively for the calorimetric experimental measurements, and thus also the residual entropies as a function of dilution. Features of the dilution physics in the specific heat are captured quantitatively by the microscopic models and the interplay between dilution and frustration is understood on the basis of a Bethe lattice calculation. The effect of the dipolar interactions between magnetic spins are exposed numerically for various dilution concentrations. Our work explains the previous discrepancy of the residual entropy between different species of rare earth ions and the generalized Pauling's estimate.

Lin, Taoran; Ke, Xianglin; Thesberg, Mischa; Schiffer, Peter; Melko, Roger; Gingras, Michel

2012-02-01

27

Calorimetric Studies at the New Hydrogen Energy Laboratory in Japan  

NASA Astrophysics Data System (ADS)

Experiments using China Lake type calorimetric cells produced excess power in three out of three experiments and no excess power in three control studies. A detailed analysis is presented for two experiments using the China Lake cells. Anomalous thermistor signals in Cell A suggest the emission of electromagnetic radiation from the active palladium cathode. Experiments in Fleischmann-Pons type calorimetric cells produced excess power in six out of eight experiments. These studies involved palladium alloy cathodes, co-deposition of palladium and deuterium from the solution, and electromigration using thin palladium wires.

Miles, Melvin H.

2000-03-01

28

An automated calorimetric method of loss measurement in electrical machines  

NASA Astrophysics Data System (ADS)

Traditionally the losses dissipated in an electrical machine have been determined from the difference between the measured input and output powers. However, the achievable accuracy is limited by the uncertainty of measurement errors, particularly if the machine is supplied with distorted voltage and current waveforms. Therefore, a more appropriate approach is to employ a calorimetric method in which the losses are determined by direct measurement of the dissipated heat. This paper describes the control and instrumentation of such an automated calorimetric system which has been commissioned to accomodate machines of up to 75 kW rating, and in which losses can be measured to an accuracy better than 10 W.

Baholo, B.; Mellor, P. H.; Howe, D.; Birch, T. S.

1994-05-01

29

Application of a downstream calorimetric probe to reactive plasma  

SciTech Connect

We explore the application of calorimetric probe located downstream from the plasma zone. By positioning the probe in a downstream location, the probe signal can be correlated with the integral energy flux carried by the effluent species as they propagate downstream from the plasma zone. Because the integral energy flux channeled downstream depends on the plasma conditions, it is possible to infer the plasma conditions from the probe response even though the probe is located away from the plasma zone. A calorimetric probe, based on resistance-temperature detector principle, adequate for fluorine plasma exposure is constructed. Probe operation is demonstrated for NF{sub 3}-Ar plasmas.

Chen, I.-S.; Neuner, Jeffery W.; Chen, Philip S.H.; Welch, James J.; DiMeo, Frank Jr. [ATMI, 7 Commerce Drive, Danbury, Connecticut 06810 (United States)

2005-12-05

30

Application of a downstream calorimetric probe to reactive plasma  

NASA Astrophysics Data System (ADS)

We explore the application of calorimetric probe located downstream from the plasma zone. By positioning the probe in a downstream location, the probe signal can be correlated with the integral energy flux carried by the effluent species as they propagate downstream from the plasma zone. Because the integral energy flux channeled downstream depends on the plasma conditions, it is possible to infer the plasma conditions from the probe response even though the probe is located away from the plasma zone. A calorimetric probe, based on resistance-temperature detector principle, adequate for fluorine plasma exposure is constructed. Probe operation is demonstrated for NF3-Ar plasmas.

Chen, Ing-Shin; Neuner, Jeffery W.; Chen, Philip S. H.; Welch, James J.; DiMeo, Frank

2005-12-01

31

Calorimetric Investigation of Hydrogen Bonding of Formamide and Its Methyl Derivatives in Organic Solvents and Water  

NASA Astrophysics Data System (ADS)

Formamide and its derivatives have a large number of practical applications; also they are structural fragments of many biomolecules. Hydrogen bonds strongly affect their physicochemical properties. In the present work a calorimetric study of formamide and its methyl derivatives was carried out. Enthalpies of solution at infinite dilution of formamide, N-methylformamide, and N, N-dimethylformamide in organic solvents at 298.15 K were measured. The relationships between the obtained enthalpies of solvation and the structure of the studied compounds were observed. Hydrogen-bond enthalpies of amides with chlorinated alkanes, ethers, ketones, esters, nitriles, amines, alcohols, and water were determined. The strength of hydrogen bonds of formamide, N-methylformamide, and N, N-dimethylformamide with proton donor solvents is practically equal. Enthalpies of hydrogen bonds of formamide with the proton acceptor solvents are two times larger in magnitude than the enthalpies of N-methylformamide. The process of hydrogen bonding of amides in aliphatic alcohols and water is complicated. The obtained enthalpies of hydrogen bonding in aliphatic alcohols vary considerably from the amide structure due to the competition between solute-solvent and solvent-solvent hydrogen bonds. Fourier transform infrared spectroscopic measurements were carried out to explain the calorimetric data. Hydration enthalpies of methyl derivatives of formamides contain a contribution of the hydrophobic effect. New thermochemical data on the hydrogen bonding of formamides may be useful for predicting the properties of biomacromolecules.

Varfolomeev, Mikhail A.; Rakipov, Ilnaz T.; Solomonov, Boris N.

2013-04-01

32

Calorimetric glass transition explained by hierarchical dynamic facilitation  

E-print Network

Calorimetric glass transition explained by hierarchical dynamic facilitation Aaron S. Keysa Contributed by David Chandler, February 11, 2013 (sent for review November 15, 2012) The glass transition different on cooling than on heating, and the response to melting a glass depends markedly on the cooling

Garrahan, Juan P.

33

Isoperibolic Calorimetric Measurements of the Fleischmann-Pons Effect  

Microsoft Academic Search

Important advantages exist for selecting a Dewar type isoperibolic calorimeter for measurements of anomalous excess enthalpy produced by the Fleischmann-Pons Effect (FPE). These advantages include a wide dynamic range for both the cell temperature and cell input power, direct visual observations inside the cell during calorimetric experiments, relative low cost, self- purification of the system, the safety of an open

Melvin H. Miles; Martin Fleischmann

34

Differential scanning calorimetric investigations of naturally dehydrated aqueous sucrose solutions  

Microsoft Academic Search

Differential scanning calorimetric investigations have been conducted on sucrose solutions for temperatures T 92, the room temperature phase is amorphous, as indicated by its x-ray diffraction pattern. A melting transition is reported for the first time for these

A. S. Paranjpe

1998-01-01

35

Application of a downstream calorimetric probe to reactive plasma  

Microsoft Academic Search

We explore the application of calorimetric probe located downstream from the plasma zone. By positioning the probe in a downstream location, the probe signal can be correlated with the integral energy flux carried by the effluent species as they propagate downstream from the plasma zone. Because the integral energy flux channeled downstream depends on the plasma conditions, it is possible

Ing-Shin Chen; Jeffery W. Neuner; Philip S. H. Chen; James J. Welch; Frank Jr. DiMeo

2005-01-01

36

Calorimetric Thermometry of Meteoritic Troilite: Early Reconnaissance  

NASA Astrophysics Data System (ADS)

Troilite (FeS) exhibits two solid-state phase transformations, which, according to conventional thermodynamic literature [1,2], occur at 411 +- 3 K (alpha/beta) and 598 +- 3 K (beta/gamma). In principal, the thermal history of a particular troilite sample might be expected to impart structural or strain characteristics that could be measured upon experimental inducement of the phase transformations. To investigate that possibility, we applied differential scanning calorimetry (DSC) to determine the temperatures and enthalpy changes for phase transitions of various troilite samples subjected to controlled heating [3]. Post-heating residues were prepared as polished grain mounts and petrologically characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDS). Troilite grains separated from the Mundrabilla (octahedrite), PAT91501 (L7 chondrite), and EET83213 (L3 chondrite) meteorites were compared with terrestrial troilite from an ultramafic complex in Del Norte Co., California. Both the alpha/beta and beta/gamma transitions were easily measured by DSC applied to samples on the order of 5 milligrams. Extrapolated-onset temperatures (the DSC approximation of equilibrium transition temperatures) for the alpha/beta transition display a systematic progression as follows: Mundrabilla, PAT91501, EET83213, Del Norte (Fig. 1). At least for Mundrabilla, PAT91501, and Del Norte, there also exists an apparent correlation of transition enthalpy with onset temperature (Fig. 1). (Enthalpy measurements for EET83213 troilite were systematically low, by dilution effects from admixed Ni-Fe metal, and require correction before such comparison.) Although Mundrabilla troilite contains on the order of 1 wt% Cr, and some grains of PAT91501 troilite contain on the order of 1 wt% Ni, it is doubtful that compositional differences can fully account for the measured differences in thermodynamic properties. Instead, it is likely that first-order differences are the consequence of different thermal histories. Multiple samples of Del Norte troilite were used to determine the influence of laboratory-scale thermal histories on DSC signatures by heating and cooling each sample under different programmed conditions. In reconnaissance experiments, maximum temperature achieved during heat treatment appears to be more influential than does either the time maintained at temperature or the heating/cooling rate. The experimentally measured alpha/beta onset temperature shows a systematic decline with maximum temperature achieved during prior heating, suggesting that high onset temperatures are indicative of low maximum temperatures in the natural histories of the troilite samples. That trend is at least qualitatively consistent with the petrologic rankings of the meteorites in which troilite from the relatively unmetamorphosed L3 chondrite shows a higher onset temperature than does troilite from either the highly metamorphosed L7 chondrite or the octahedrite. Additional work should define the limits of a quantitative calibration that might ultimately permit derivation of meteorite thermal histories by calorimetric thermometry of troilite. Samples were kindly provided by E. R. D. Scott (Mundrabilla), C. B. Moore (Del Norte), and the Meteorite Working Group (PAT91501; EET83213 powder from E. Jarosewich). References: [1] Chase M. W. Jr. et al. (1985) JANAF Thermochemical Tables, 3rd ed., 1194. [2] Robie R. A. et al. (1979) Geol. Surv. Bull. 1452, 125. [3] Allton J. H. and Gooding J. L. (1993) LPS XXIV, 21-22. Fig. 1, which appears here in the hard copy, shows the thermodynamics of troilite alpha/beta phase transformations measured by DSC during first-heat cycles.

Allton, J. H.; Wentworth, S. J.; Gooding, J. L.

1993-07-01

37

Theoretical study and design of a new calorimetric tunnel  

NASA Astrophysics Data System (ADS)

An enlargement of the Pilsner R&D park consisted of several new buildings is running nowadays. The University of West Bohemia, New technology Research centre, will be using one of the buildings also for hosting the calorimetric tunnel. With respect to our experience with currently operated calorimetric tunnel with lower power and smaller size, a new tunnel of higher power and better parameters was designed. The tunnel was proposed on the base of 10 analytical calculations respecting wide range of operational regimes and possible different target applications. Together with analytical computations, also some simplified CFD simulations were done. These simulations gave us information about the flow field in the tunnel and especially in the measuring area. Some non- standardized parts of the tunnel were proposed, designed and verified with the use of CFD. The tunnel design together with its parameters and results of CFD analysis are presented in the paper.

Sedlá?ek, Jan; K?ourek, Jind?ích; K?s, Michal

2012-04-01

38

Critical behavior at nematic-smectic-A1 phase transitions. I. High-resolution x-ray-scattering and calorimetric study of the liquid-crystal octyloxyphenylnitrobenzoyloxy benzoate  

Microsoft Academic Search

High-resolution x-ray scattering and ac-calorimetric measurements have been carried out near the nematic-smectic-A1 phase transition of the pure liquid-crystal compound octyloxyphenylnitrobenzoyl- oxy benzoate (DB8ONO2). Several forms of the structure factor S(q) for fitting the x-ray line shape have been tested. The critical temperature dependences of the resulting longitudinal and transverse correlation lengths xi|| and xi? and the smectic susceptibility sigma

G. Nounesis; K. I. Blum; M. J. Young; C. W. Garland; R. J. Birgeneau

1993-01-01

39

45 CFR 233.145 - Expiration of medical assistance programs under titles I, IV-A, X, XIV and XVI of the Social...  

Code of Federal Regulations, 2012 CFR

...assistance programs under titles I, IV-A, X, XIV and XVI of the Social Security Act...assistance programs under titles I, IV-A, X, XIV and XVI of the Social Security Act...made to any State under title I, IV-A, X, XIV or XVI of the Social...

2012-10-01

40

45 CFR 233.145 - Expiration of medical assistance programs under titles I, IV-A, X, XIV and XVI of the Social...  

Code of Federal Regulations, 2013 CFR

...assistance programs under titles I, IV-A, X, XIV and XVI of the Social Security Act...assistance programs under titles I, IV-A, X, XIV and XVI of the Social Security Act...made to any State under title I, IV-A, X, XIV or XVI of the Social...

2013-10-01

41

45 CFR 233.145 - Expiration of medical assistance programs under titles I, IV-A, X, XIV and XVI of the Social...  

Code of Federal Regulations, 2011 CFR

...assistance programs under titles I, IV-A, X, XIV and XVI of the Social Security Act...assistance programs under titles I, IV-A, X, XIV and XVI of the Social Security Act...made to any State under title I, IV-A, X, XIV or XVI of the Social...

2011-10-01

42

A speech given in the precence of His Majesty, King Karl XVI Gustav and her majesty Queen Silvia  

E-print Network

A speech given in the precence of His Majesty, King Karl XVI Gustav and her majesty Queen Silvia in the presence of His Majesty, King Karl XVI Gustav, her majesty Queen Silvia and this distin- guished company particularly happy 1 #12;that Dr. Marcus Wallenberg's outstanding and unique position in financial

Tomppo, Erkki

43

76 FR 45309 - Social Security Ruling 11-1p; Titles II and XVI: Procedures for Handling Requests To File...  

Federal Register 2010, 2011, 2012, 2013

...SSA-2011-0057] Social Security Ruling 11-1p; Titles II and XVI: Procedures for Handling Requests...when you have a pending claim of the same title and benefit type in our administrative...Security. Policy Interpretation Ruling Titles II and XVI: Procedures for Handling...

2011-07-28

44

Measurement of the calorimetric energy scale in MINOS  

SciTech Connect

MINOS is a long-baseline neutrino oscillation experiment. A neutrino beam is created at the Fermi National Accelerator Laboratory in Illinois and fired down through the Earth. Measurements of the energy spectra and composition of the neutrino beam are made both at the source using the Near detector and 735 km away at the Soudan Underground Laboratory in Minnesota using the Far detector. By comparing the spectrum and flavour composition of the neutrino beam between the two detectors neutrino oscillations can be observed. Such a comparison depends on the accuracy of the relative calorimetric energy scale. This thesis details a precise measurement of the calorimetric energy scale of the MINOS Far detector and Calibration detector using stopping muons with a new ''track window'' technique. These measurements are used to perform the relative calibration between the two detectors. This calibration has been accomplished to 1.7% in data and to significantly better than 2% in the Monte Carlo simulation, thus achieving the MINOS relative calibration target of 2%. A number of cross-checks have been performed to ensure the robustness of the calorimetric energy scale measurements. At the Calibration detector the test-beam energy between run periods is found to be consistent with the detector response to better than 2% after the relative calibration is applied. The muon energy loss in the MINOS detectors determined from Bethe-Bloch predictions, data and Monte Carlo are compared and understood. To estimate the systematic error on the measurement of the neutrino oscillation parameters caused by a relative miscalibration a study is performed. A 2% relative miscalibration is shown to cause a 0.6% bias in the values of {Delta}m{sup 2} and sin{sup 2}(2{theta}).

Hartnell, Jeffrey J.; /Oxford U.

2005-06-01

45

Two calorimetrically distinct parts of the dynamic glass transition  

NASA Astrophysics Data System (ADS)

Although known for more than thirty years, the physical nature of the glass-transition crossover region is still an open question. Heat capacity spectroscopy experiments in the crossover region of poly(n-hexyl methacrylate) are presented which indicate, for the first time, that the dynamic glass transition consists of two separate parts in series: A thermorheologically rather simple high-temperature part (called a-process) and a low-temperature part with increasing molecular cooperativity on the nanometer scale (?-process). The calorimetric experiments show, surprisingly, a decline of the a process and a separate onset of the ?-process.

Beiner, M.; Kahle, S.; Hempel, E.; Schröter, K.; Donth, E.

1998-11-01

46

SPIE Proceedings, Ophthalmic Technologies XVI, vol. 6138 (2006) Noninvasive Dosimetry and Monitoring of TTT  

E-print Network

SPIE Proceedings, Ophthalmic Technologies XVI, vol. 6138 (2006) 1 Noninvasive Dosimetry and the lack of immediately observable outcome of the therapy, a real-time dosimetry is highly desirable. We-time monitoring and dosimetry of TTT. A 795nm laser was applied in rabbit eyes for 60 seconds using a 0.86mm

Palanker, Daniel

47

Proceedings SPIE, Ophthalmic Technologies XVI, SPIE vol. 6138 (2006) Plasma-Mediated Transfection of RPE  

E-print Network

Proceedings SPIE, Ophthalmic Technologies XVI, SPIE vol. 6138 (2006) 1 Plasma-Mediated Transfection transfection of RPE without visible damage to the retina. Gene expression was quantified and monitored using bioluminescence (luciferase) and fluorescence (GFP) imaging. Transfection efficiency of RPE with this new

Palanker, Daniel

48

Volume XVI, No. 3 A publication of the U.S. Army Installation Management Agency  

E-print Network

Volume XVI, No. 3 A publication of the U.S. Army Installation Management Agency May/June 2004 U.S/June 2004 Public Works Digest is an unofficial publication of the U.S. Army Installa- tion Management Agency of the Department of the Army. Address mail to: U.S. Army Installation Management Agency 2511 Jefferson Davis

US Army Corps of Engineers

49

Volume XVI, No. 6 A publication of the U.S. Army Installation Management Agency  

E-print Network

Volume XVI, No. 6 A publication of the U.S. Army Installation Management Agency November/December 2004 U.S. Army Installation Management Agency In this issue: Annual Report Summaries #12;3 Letter from Public Works Digest is an unofficial publication of the U.S. Army Installa- tion Management Agency, under

US Army Corps of Engineers

50

A Temporal Map in Geostationary Orbit: The Cover Etching on the EchoStar XVI Artifact  

NASA Astrophysics Data System (ADS)

Geostationary satellites are unique among orbital spacecraft in that they experience no appreciable atmospheric drag. After concluding their respective missions, geostationary spacecraft remain in orbit virtually in perpetuity. As such, they represent some of human civilization's longest lasting artifacts. With this in mind, the EchoStar XVI satellite, to be launched in fall 2012, will play host to a time capsule intended as a message for the deep future. Inspired in part by the Pioneer Plaque and Voyager Golden Records, the EchoStar XVI Artifact is a pair of gold-plated aluminum jackets housing a small silicon disk containing 100 photographs. The Cover Etching, the subject of this paper, is etched onto one of the two jackets. It is a temporal map consisting of a star chart, pulsar timings, and other information describing the epoch from which EchoStar XVI came. The pulsar sample consists of 13 rapidly rotating objects, 5 of which are especially stable, having spin periods <10 ms and extremely small spin-down rates. In this paper, we discuss our approach to the time map etched onto the cover and the scientific data shown on it, and we speculate on the uses that future scientists may have for its data. The other portions of the EchoStar XVI Artifact will be discussed elsewhere.

Weisberg, Joel M.; Paglen, Trevor

2012-10-01

51

REPORT ON CALORIMETRIC STUDIES AT THE NHE LABORATORY IN SAPPORO, JAPAN  

Microsoft Academic Search

Experiments using China Lake type calorimetric cells produced excess power in three out of three experiments and no excess power in three control studies. A detailed analysis is presented for two experiments using the China Lake cells. Anomalous thermistor signals in Cell A suggest the emission of electromagnetic radiation from the active palladium cathode. Experiments in Fleischmann-Pons type calorimetric cells

MELVIN H. MILES

52

Adiabatic calorimetric decomposition studies of 50 wt.% hydroxylamine/water.  

PubMed

Calorimetric data can provide a basis for determining potential hazards in reactions, storage, and transportation of process chemicals. This work provides calorimetric data for the thermal decomposition behavior in air of 50wt.% hydroxylamine/water (HA), both with and without added stabilizers, which was measured in closed cells with an automatic pressure tracking adiabatic calorimeter (APTAC). Among the data provided are onset temperatures, reaction order, activation energies, pressures of noncondensable products, thermal stability at 100 degrees C, and the effect of HA storage time. Discussed also are the catalytic effects of carbon steel, stainless steel, stainless steel with silica coating, inconel, titanium, and titanium with silica coating on the reaction self-heat rates and onset temperatures. In borosilicate glass cells, HA was relatively stable at temperatures up to 133 degrees C, where the HA decomposition self-heat rate reached 0.05 degrees C/min. The added stabilizers appeared to reduce HA decomposition rates in glass cells and at ambient temperatures. The tested metals and metal surfaces coated with silica acted as catalysts to lower the onset temperatures and increase the self-heat rates. PMID:11165058

Cisneros, L O; Rogers, W J; Mannan, M S

2001-03-19

53

The phenomenon of conglomerate crystallization. XVIII. Clavic dissymmetry in coordination compounds. XVI  

Microsoft Academic Search

The x-ray crystal structure of {[Co(NH3)4(CO3)]NO3}2 · H2O has been determined as part of a study of the intra- and interionic interactions present in crystals of several transition-metal-amine complexes chosen to examine the occurrence and causes of conglomerate crystallization. {[Co(NH3)4(CO3)]NO3}2 · H2O crystallizes in the monoclinic space group P21\\/n with cell constantsa=7.4960(9)Å,b=22.673(6),c=10.513(1), andß=91.41(1)°;V=1786.12 Å3, andd(calc;Z=4)=1.915 g cm-3. In all, 5333

Ivan Bernal; James Cetrullo

1990-01-01

54

20 CFR 408.930 - Are title II and title XVI benefits subject to adjustment to recover title VIII overpayments?  

Code of Federal Regulations, 2010 CFR

...would receive. For title II benefits, it includes your monthly benefit and your past-due benefits after any reductions or deductions...this chapter. For title XVI benefits, it includes your monthly benefit and your past-due...

2010-04-01

55

20 CFR 416.572 - Are title II and title VIII benefits subject to adjustment to recover title XVI overpayments?  

Code of Federal Regulations, 2010 CFR

...416.572 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL...title XVI overpayments from benefits payable to you under title II or title VIII of the Social Security Act. (2) Benefits payable. For...

2010-04-01

56

Nanoclay modified polycarbonate blend nanocomposites: Calorimetric and mechanical properties  

NASA Astrophysics Data System (ADS)

The research is devoted to characterization of polycarbonate (PC)/acrylonitrile-butadiene styrene (ABS) blend nanocomposites in respects to it mechanical and calorimetric properties. It is shown that PC blend with 10wt% of ABS is more suitable for development of polymer-clay nanocomposites than PC blend with 40wt.% of ABS. It is revealed that the greatest modulus and strength increment is observed for PC/10wt.%ABS blend nanocomposites, containing aromatic organomodifier treated clay (Dellite 43B). It is also determined that optimal nanofiller content for the investigated PC/10%ABS blend is 1.5 wt.%. Increase of mechanical characteristics of PC/10wt.%ABS blend nanocomposites is accompanied with the rise of glass transition temperatures of both polymeric phases, particularly that of PC.

Zicans, Janis; Meri, Remo Merijs; Ivanova, Tatjana; Berzina, Rita; Kalnins, Martins; Maksimovs, Roberts

2014-05-01

57

Fast electron thermometry towards ultra-sensitive calorimetric detection  

E-print Network

We demonstrate radiofrequency thermometry on a micrometer-sized metallic island below 100 mK. Our device is based on a normal metal-insulator-superconductor tunnel junction coupled to a resonator with transmission readout. In the first generation of the device, we achieve 90 {\\mu}K/Hz^1/2 noise-equivalent temperature with 10 MHz bandwidth. We measure the thermal relaxation time of the electron gas in the island, which we find to be of the order of 100 {\\mu}s. Such a calorimetric detector, upon optimization, can be seamlessly integrated into superconducting circuits, with immediate applications in quantum-thermodynamics experiments down to single quanta of energy.

S. Gasparinetti; K. L. Viisanen; O. -P. Saira; T. Faivre; M. Arzeo; M. Meschke; J. P. Pekola

2014-05-29

58

The calorimetric measurement of low energy brachytherapy sources  

NASA Astrophysics Data System (ADS)

Historically, the dose rate to tissue from 125I and 103Pd sources was based on a source's apparent activity in free space. The American Association of Physicists in Medicine Task Group 43 (TG43) established a protocol that clarified this formalism for the dose rate determination that was universally accepted in the Medical Physics community. The TG43 protocol is based on air kerma strength and a different set of conversion factors for determining the dose rate. However, there are still many uncertainties associated with this methodology. These uncertainties are predominantly the result of the unknown effects of variations in the source encapsulation and internal source structure on the dose distribution surrounding a source. Currently, there is no method of nondestructively determining the contained radioactivity of brachytherapy sources. Without the knowledge of the contained activity, the effects of source construction variations cannot be evaluated accurately. The goal of this work was to develop a calorimeter that measures the total power generated by a source. This information could then be used to nondestructively determine the contained radioactivity activity of a source. The power generated by three different, well characterized source designs of 125I brachytherapy seeds was measured with the calorimeter. A theoretical model of the calorimeter was also developed to demonstrate that the calorimeter operated as expected. The measured and theoretical temperature results for the three different source models were consistent within the uncertainty of the measurements. The consistency between the calorimetric measurements and the theoretical expected results demonstrates proof of principle of the calorimeter. The information determined from the model can also be useful for future calorimetric research by identifying required calorimeter design features, potential design improvements and potential difficulties.

Aus, Robert John

59

Genomic analysis of the blood attributed to Louis XVI (1754-1793), king of France  

PubMed Central

A pyrographically decorated gourd, dated to the French Revolution period, has been alleged to contain a handkerchief dipped into the blood of the French king Louis XVI (1754–1793) after his beheading but recent analyses of living males from two Bourbon branches cast doubts on its authenticity. We sequenced the complete genome of the DNA contained in the gourd at low coverage (~2.5×) with coding sequences enriched at a higher ~7.3× coverage. We found that the ancestry of the gourd's genome does not seem compatible with Louis XVI's known ancestry. From a functional perspective, we did not find an excess of alleles contributing to height despite being described as the tallest person in Court. In addition, the eye colour prediction supported brown eyes, while Louis XVI had blue eyes. This is the first draft genome generated from a person who lived in a recent historical period; however, our results suggest that this sample may not correspond to the alleged king. PMID:24763138

Olalde, Inigo; Sanchez-Quinto, Federico; Datta, Debayan; Marigorta, Urko M.; Chiang, Charleston W. K.; Rodriguez, Juan Antonio; Fernandez-Callejo, Marcos; Gonzalez, Irene; Montfort, Magda; Matas-Lalueza, Laura; Civit, Sergi; Luiselli, Donata; Charlier, Philippe; Pettener, Davide; Ramirez, Oscar; Navarro, Arcadi; Himmelbauer, Heinz; Marques-Bonet, Tomas; Lalueza-Fox, Carles

2014-01-01

60

A Temporal Map in Geostationary Orbit: The Cover Etching on the EchoStar XVI Artifact  

E-print Network

Geostationary satellites are unique among orbital spacecraft in that they experience no appreciable atmospheric drag. After concluding their respective missions, geostationary spacecraft remain in orbit virtually in perpetuity. As such, they represent some of human civilization's longest lasting artifacts. With this in mind, the EchoStar XVI satellite, to be launched in fall 2012, will play host to a time capsule intended as a message for the deep future. Inspired in part by the Pioneer Plaque and Voyager Golden Records, the EchoStar XVI Artifact is a pair of gold-plated aluminum jackets housing a small silicon disc containing one hundred photographs. The Cover Etching, the subject of this paper, is etched onto one of the two jackets. It is a temporal map consisting of a star chart, pulsar timings, and other information describing the epoch from which EchoStar XVI came. The pulsar sample consists of 13 rapidly rotating objects, 5 of which are especially stable, having spin periods < 10 ms and extremely sma...

Weisberg, J M

2012-01-01

61

VizieR Online Data Catalog: Fe XVI radiative rates (Diaz+, 2013)  

NASA Astrophysics Data System (ADS)

Accurate theoretical energy level, lifetime, and transition probability calculations of core-excited Fe XVI were performed employing the relativistic Multireference Moller-Plesset perturbation theory. In these computations the term energies of the highly excited n<=5 states arising from the configuration 1s22sk2pm3lpnl'q, where k+m+p+q=9, l<=3 and p+q<=2 are considered, including those of the autoionizing levels with a hole-state in the L-shell. All even and odd parity states of sodium-like iron ion were included for a total of 1784 levels. Comparison of the calculated L-shell transition wavelengths with those from laboratory measurements shows excellent agreement. Therefore, our calculation may be used to predict the wavelengths of as of yet unobserved Fe XVI, such as the second strongest 2p-3d Fe XVI line, which has not been directly observed in the laboratory and which blends with one of the prominent Fe XVII lines. (2 data files).

Diaz, F.; Vilkas, M. J.; Ishikawa, Y.; Beiersdorfer, P.

2013-08-01

62

Adsorption of methylene blue on raw and MTZ/imogolite hybrid surfaces: effect of concentration and calorimetric investigation.  

PubMed

The synthetic imogolite sample was used for organofunctionalization process with 2-mercaptothiazoline (MTZ). The compound 2-mercaptothiazoline was anchored onto imogolite surface by heterogeneous route. Due to the increment of basic centers attached to the pendant chains the dye adsorption capability of the final chelating material, was found to be higher than is precursor. The ability of these materials to remove methylene blue from aqueous solution was followed by a series of adsorption isotherms at room temperature and pH 4.0. The maximum number of moles adsorbed was determined to be 40.32×10(-2) and 65.13×10(-2) mmol g(-1) for IMO and IMO(MTZ), respectively. The energetic effects caused by dye cations adsorption were determined through calorimetric titrations. Thermodynamics indicated the existence of favorable conditions for such methylene blue-nitrogen and sulfur interactions. PMID:20674169

Guerra, Denis L; Batista, Adriano C; Viana, Rúbia R; Airoldi, Claudio

2010-11-15

63

Enthalpies of formation of the Al–Nb intermetallic compounds  

Microsoft Academic Search

The enthalpies of formation of the intermetallic compounds of the Al–Nb system were measured by direct reaction calorimetry at high temperatures. Results were compared with the available experimental values based on calorimetric and vapor pressure measurements and computed values based on the semiempirical model of Miedema. X-ray Powder Diffraction and Electron Microprobe Analysis techniques were used to verify the crystal

Kamal Mahdouk; Jean-Claude Gachon; Lahcen Bouirden

1998-01-01

64

The Calorimetric Glass Transition of Polystyrene Ultrathin Films  

NASA Astrophysics Data System (ADS)

The glass transition temperature (Tg) for nanoconfined materials have been widely studied since the early 1990s. For supported polystyrene ultrathin films, Tg differs from bulk value. Recent work has attributed nanoconstrained Tg effects to artifact. In this study, we attempted to resolve this controversy and measure Tg for single polystyrene ultrathin films using Flash DSC. Films have been prepared in two ways: spincast films placed on a layer of inert oil or grease and films directly spincast on the back of the calorimetric chip. For the films on oil or on grease, the 160 nm thick films show no Tg depression. On the other hand, thinner films on oil and on grease show a Tg depression which decreases with increasing cooling rate. The depression reverts to the bulk values over the course of a day at 160 ^oC due to dewetting and thickening. For directly spincast films, no Tg depression is observed, consistent with results from other nanocalorimetry work. Our results are consistent with literature results that Tg decreases with decreasing substrate surface energy, and they also demonstrate that the Tg depression observed is not due to degradation or to plasticization effects.

Gao, Siyang; Koh, Yung P.; Simon, Sindee S.

2013-03-01

65

Adiabatic Heat of Hydration Calorimetric Measurements for Reference Saltstone Waste  

SciTech Connect

The production of nuclear materials for weapons, medical, and space applications from the mid-1950's through the late-1980's at the Savannah River Site (SRS) generated approximately 35 million gallons of liquid high-level radioactive waste, which is currently being processed into vitrified glass for long-term storage. Upstream of the vitrification process, the waste is separated into three components: high activity insoluble sludge, high activity insoluble salt, and very low activity soluble salts. The soluble salt represents 90% of the 35 million gallons of overall waste and is processed at the SRS Saltstone Facility, where it mixed with cement, blast furnace slag, and flyash, creating a grout-like mixture. The resulting grout is pumped into aboveground storage vaults, where it hydrates into concrete monoliths, called saltstone, thus immobilizing the low-level radioactive salt waste. As the saltstone hydrates, it generates heat that slowly diffuses out of the poured material. To ensure acceptable grout properties for disposal and immobilization of the salt waste, the grout temperature must not exceed 95 C during hydration. Adiabatic calorimetric measurements of the heat generated for a representative sample of saltstone were made to determine the time-dependent heat source term. These measurements subsequently were utilized as input to a numerical conjugate heat transfer model to determine the expected peak temperatures for the saltstone vaults.

Bollinger, James

2006-01-12

66

Neutron induced capture and fission discrimination using calorimetric shape decomposition  

NASA Astrophysics Data System (ADS)

The neutron capture and fission cross-sections of 233U have been measured at the neutron time-of-flight facility n_TOF at CERN in the energy range from 1 eV to 1 keV using a high performance 4? BaF2 Total Absorption Calorimeter (TAC) as a detection device. In order to separate the contributions of neutron capture and neutron induced fission in the TAC, a methodology called Calorimetric Shape Decomposition (CSD) was developed. The CSD methodology is based on the study of the TAC's energy response for all competing reactions, allowing to discriminate between ? s originating from neutron induced fission and those from neutron capture reactions without the need for fission tagging or any additional detection system. In this article, the concept behind the CSD is explained in detail together with the necessary analysis to obtain the TAC's response to neutron capture and neutron induced fission. The discrimination between capture and fission contributions is shown for several neutron energies. A comparison between the 233U neutron capture and fission yield extraction with ENDF/B-VII v1. library data is also provided.

Carrapiço, C.; Berthoumieux, E.; Dridi, W.; Gonçalves, I. F.; Gunsing, F.; Lampoudis, C.; Vaz, P.; n TOF Collaboration

67

[The strength of the shaman in Brazilian colonial medicine of the XVI and XVIII centuries].  

PubMed

The strategy of the colonial conquest of Brazil by the Portuguese, between the XVI and XVIII centuries was linked to the complex set of political, economic and military forces from the Metropolis and the Church. In the first contacts with the Indian populations, on the coast, the colonizing elements, chiefly, the religious ones, perceived the extraordinary importance of the Indian shaman in the organizational structure of the autochthonous populations. Thus, the physical and moral destruction of the Indian shaman and his substitution by healing doctors and priests had become a fundamental part of the plans designed by the Metropolis and the Church in consolidating the territorial conquest. PMID:15726752

Botelho, João Bosco

2004-01-01

68

The use of reaction calorimetric methods for measuring heats of formation of organo-metallic compounds  

Microsoft Academic Search

The measurement of the heats of formation of organo-metallic com­ pounds presents, usually, a difficult task to the experimental thermochemist. Thus the method of combustion in a conventional bomb-calorimeter, although it has been applied to a number of metallic alkyls in recent years! and yielded valuable results, is nevertheless not entirely satisfactory. The difficulty is that complete oxidation of the

H. A. Skinner; J. E. Bennett; J. B. Pedley

1961-01-01

69

Calorimetric Assembly for the Measurement of Heats of Fusion of Inorganic Compounds  

Microsoft Academic Search

The apparatus consists of a calorimeter of basically simple design, above which is a movable, vertical furnace for heating the specimen contained in a hermetically sealed platinum capsule. A complete series of measurements may thus be carried out on one sample. The capsule is dropped directly into a metal dry-chamber in the calorimeter in contact with a stirred liquid for

J. Goodkin; C. Solomons; G. J. Janz

1958-01-01

70

Thermodynamic properties of chlorite and berthierine derived from calorimetric measurements  

NASA Astrophysics Data System (ADS)

In the context of the deep waste disposal, we have investigated the respective stabilities of two iron-bearing clay minerals: berthierine ISGS from Illinois [USA; (Al0.975FeIII0.182FeII1.422Mg0.157Li0.035Mn0.002)(Si1.332Al0.668)O5(OH)4] and chlorite CCa-2 from Flagstaff Hill, California [USA; (Si2.633Al1.367)(Al1.116FeIII0.215Mg2.952FeII1.712Mn0.012Ca0.011)O10(OH)8]. For berthierine, the complete thermodynamic dataset was determined at 1 bar and from 2 to 310 K, using calorimetric methods. The standard enthalpies of formation were obtained by solution-reaction calorimetry at 298.15 K, and the heat capacities were measured by heat-pulse calorimetry. For chlorite, the standard enthalpy of formation is measured by solution-reaction calorimetry at 298.15 K. This is completing the entropy and heat capacity obtained previously by Gailhanou et al. (Geochim Cosmochim Acta 73:4738-4749, 2009) between 2 and 520 K, by using low-temperature adiabatic calorimetry and differential scanning calorimetry. For both minerals, the standard entropies and the Gibbs free energies of formation at 298.15 K were then calculated. An assessment of the measured properties could be carried out with respect to literature data. Eventually, the thermodynamic dataset allowed realizing theoretical calculations concerning the berthierine to chlorite transition. The latter showed that, from a thermodynamic viewpoint, the main factor controlling this transition is probably the composition of the berthierine and chlorite minerals and the nature of the secondary minerals rather than temperature.

Blanc, Philippe; Gailhanou, Hélène; Rogez, Jacques; Mikaelian, Georges; Kawaji, Hitoshi; Warmont, Fabienne; Gaboreau, Stéphane; Grangeon, Sylvain; Grenèche, Jean-Marc; Vieillard, Philippe; Fialips, Claire I.; Giffaut, Eric; Gaucher, Eric C.; Claret, F.

2014-09-01

71

Calorimetric and computational study of the thermochemistry of phenoxyphenols.  

PubMed

Thermodynamic properties of 3- and 4-phenoxyphenol have been determined by using a combination of calorimetric and effusion techniques as well as by high-level ab initio molecular orbital calculations. The standard (p° = 0.1 MPa) molar enthalpies of formation in the condensed and gas states, ?(f)H(m)°(cr or l) and ?(f)H(m)°(g), at T = 298.15 K, of 3- and 4-phenoxyphenol were derived from their energies of combustion in oxygen, measured by a static bomb calorimeter, and from the enthalpies of vaporization or sublimation derived respectively by Calvet microcalorimetry for the 3-phenoxyphenol and by Knudsen effusion technique for the 4-phenoxyphenol. The theoretically estimated gas-phase enthalpies of formation were calculated from high-level ab initio molecular orbital calculations at the G3(MP2)//B3LYP level of theory. Furthermore, this composite approach was also used to obtain information about the gas-phase acidities, gas-phase basicities, proton and electron affinities, adiabatic ionization enthalpies, and, finally, O?H bond dissociation enthalpies. The good agreement between the G3MP2B3-derived values and the experimental gas-phase enthalpies of formation for the 3- and 4-phenoxyphenol gives confidence to the estimate concerning the 2-phenoxyphenol isomer, which was not experimentally studied, and to the estimates concerning the radical and the anion. Additionally, the experimental values of gas-phase enthalpies of formation were also compared with estimates based on the empirical scheme developed by Cox. PMID:21486007

Ribeiro da Silva, Manuel A V; Lobo Ferreira, Ana I M C; Cimas, Álvaro

2011-05-20

72

Selection of non-destructive assay methods: Neutron counting or calorimetric assay?  

SciTech Connect

The transition of DOE facilities from production to D&D has lead to more measurements of product, waste, scrap, and other less attractive materials. Some of these materials are difficult to analyze by either neutron counting or calorimetric assay. To determine the most efficacious analysis method, variety of materials, impure salts and hydrofluorination residues have been assayed by both calorimetric assay and neutron counting. New data will be presented together with a review of published data. The precision and accuracy of these measurements are compared to chemistry values and are reported. The contribution of the gamma ray isotopic determination measurement to the overall error of the calorimetric assay or neutron assay is examined and discussed. Other factors affecting selection of the most appropriate non-destructive assay method are listed and considered.

Cremers, T.L.; Wachter, J.R.

1994-08-01

73

Effect of Heat Generation of Ultrasound Transducer on Ultrasonic Power Measured by Calorimetric Method  

NASA Astrophysics Data System (ADS)

Ultrasonic power is one of the key quantities closely related to the safety of medical ultrasonic equipment. An ultrasonic power standard is required for establishment of safety. Generally, an ultrasonic power standard below approximately 20 W is established by the radiation force balance (RFB) method as the most accurate measurement method. However, RFB is not suitable for high ultrasonic power because of thermal damage to the absorbing target. Consequently, an alternative method to RFB is required. We have been developing a measurement technique for high ultrasonic power by the calorimetric method. In this study, we examined the effect of heat generation of an ultrasound transducer on ultrasonic power measured by the calorimetric method. As a result, an excessively high ultrasonic power was measured owing to the effect of heat generation from internal loss in the transducer. A reference ultrasound transducer with low heat generation is required for a high ultrasonic power standard established by the calorimetric method.

Uchida, Takeyoshi; Kikuchi, Tsuneo

2013-07-01

74

Comparing M31 and Milky Way Satellites: The Extended Star Formation Histories of Andromeda II and Andromeda XVI  

E-print Network

We present the first comparison between the lifetime star formation histories (SFHs) of M31 and Milky Way (MW) satellites. Using the Advanced Camera for Surveys aboard the Hubble Space Telescope, we obtained deep optical imaging of Andromeda II (M$_{V} = -$12.0; log(M$_{\\star}$/M$_{\\odot}$) $\\sim$ 6.7) and Andromeda XVI (M$_{V} = -$7.5; log(M$_{\\star}$/M$_{\\odot}$) $\\sim$ 4.9) yielding color-magnitude diagrams that extend at least 1 magnitude below the oldest main sequence turnoff, and are similar in quality to those available for the MW companions. And II and And XVI show strikingly similar SFHs: both formed 50-70% of their total stellar mass between 12.5 and 5 Gyr ago (z$\\sim$5-0.5) and both were abruptly quenched $\\sim$ 5 Gyr ago (z$\\sim$0.5). The predominance of intermediate age populations in And XVI makes it qualitatively different from faint companions of the MW and clearly not a pre-reionization fossil. Neither And II nor And XVI appears to have a clear analog among MW companions, and the degree of si...

Weisz, Daniel R; Hidalgo, Sebastian L; Monelli, Matteo; Dolphin, Andrew E; McConnachie, Alan; Bernard, Edouard J; Gallart, Carme; Aparicio, Antonio; Boylan-Kolchin, Michael; Cassisi, Santi; Cole, Andrew A; Ferguson, Henry C; Irwin, Mike; Martin, Nicolas F; Mayer, Lucio; McQuinn, Kristen B W; Navarro, Julio F; Stetson, Peter B

2014-01-01

75

78 FR 17744 - Social Security Ruling, SSR 13-2p; Titles II and XVI: Evaluating Cases Involving Drug Addiction...  

Federal Register 2010, 2011, 2012, 2013

...13-2p; Titles II and XVI: Evaluating Cases Involving Drug Addiction and Alcoholism...question 8. ``What evidence do we need in cases involving DAA?'', a., italicize the...page 11946, second column, under ``15. How should adjudicators consider...

2013-03-22

76

First Calorimetric Measurement of OI-line in the Electron Capture Spectrum of $^{163}$Ho  

E-print Network

The isotope $^{163}$Ho undergoes an electron capture process with a recommended value for the energy available to the decay, $Q_{\\rm EC}$, of about 2.5 keV. According to the present knowledge, this is the lowest $Q_{\\rm EC}$ value for electron capture processes. Because of that, $^{163}$Ho is the best candidate to perform experiments to investigate the value of the electron neutrino mass based on the analysis of the calorimetrically measured spectrum. We present for the first time the calorimetric measurement of the atomic de-excitation of the $^{163}$Dy daughter atom upon the capture of an electron from the 5s shell in $^{163}$Ho, OI-line. The measured peak energy is 48 eV. This measurement was performed using low temperature metallic magnetic calorimeters with the $^{163}$Ho ion implanted in the absorber. We demonstrate that the calorimetric spectrum of $^{163}$Ho can be measured with high precision and that the parameters describing the spectrum can be learned from the analysis of the data. Finally, we discuss the implications of this result for the Electron Capture $^{163}$Ho experiment, ECHo, aiming to reach sub-eV sensitivity on the electron neutrino mass by a high precision and high statistics calorimetric measurement of the $^{163}$Ho spectrum.

P. C. -O. Ranitzsch; C. Hassel; M. Wegner; S. Kempf; A. Fleischmann; C. Enss; L. Gastaldo; A. Herlert; K. Johnston

2014-08-30

77

Calorimetric detection of the conical THz radiation from femtosecond laser filaments in air  

E-print Network

1 Calorimetric detection of the conical THz radiation from femtosecond laser filaments in air Aur (THz) emission from a femtosecond laser filament in air is measured with a bolometric detector and a set of filters, confirming that the main part of the emission lies between 0.5 and 3 THz

Paris-Sud XI, Université de

78

Measurements of AC losses in HTSC wires exposed to an alternating field using calorimetric methods  

Microsoft Academic Search

Calorimetric methods for AC loss measurement for short superconducting wires have been investigated. The design, operation and results obtained from an experimental calorimeter are described. With these methods the total loss of a short superconducting sample exposed to a 50 Hz alternating field, both perpendicular and axial, have been measured with an accuracy of microwatts per centimeter. The sample is

Tri Hardono; Christopher D. Cook; Jian-Xun Jin

1999-01-01

79

Calorimetric determination of the enzyme activity immobilised on macroporous glass membranes  

Microsoft Academic Search

A direct method for the determination of the catalytic activity of immobilised enzymes by use of a miniaturised calorimeter is presented. The possibilities and advantages of the calorimetric method are demonstrated by investigations with catalase immobilised on macroporous glass membranes as model enzyme. The investigated enzyme carrier systems are characterised by a high catalytic activity, a marked long-term stability and

Hagen Graebner; Regina Hüttl; Gert Wolf

2002-01-01

80

The Hydrogen Bonding of Cytosinewith Guanine:Calorimetric and`H-NMR Analysis  

E-print Network

The Hydrogen Bonding of Cytosinewith Guanine:Calorimetric and`H-NMR Analysis of the Molecular forming hydrogen bonds. Consequently, hydrogen-bond formation in our system is primarily between the bases-pair formation in o-dichlorobenzeneis -6.65 0.32 kcal/mol. Since o-dichlorobenzenedoes not form hydrogen bonds

Williams, Loren

81

Micro-calorimetric sensor for vapor phase explosive detection with optimized heat profile  

Microsoft Academic Search

A heater design, used in a micro-calorimetric sensor, has been optimized for temperature uniformity in order to increase the sensitivity and reliability of detection of trace amounts of explosives. In this abstract the design, fabrication and characterization is described. The performance of the novel heater design is characterized by measuring the temperature coefficient of resistivity (TCR) values and by mapping

A. Greve; J. K. Olsen; N. Privorotskaya; L. Senesac; T. Thundat; W. P. King; A. Boisen

2010-01-01

82

Heat capacty, relative enthalpy, and calorimetric entropy of silicate minerals: an empirical method of prediction.  

USGS Publications Warehouse

Through the evaluation of experimental calorimetric data and estimates of the molar isobaric heat capacities, relative enthalpies and entropies of constituent oxides, a procedure for predicting the thermodynamic properties of silicates is developed. Estimates of the accuracy and precision of the technique and examples of its application are also presented. -J.A.Z.

Robinson, Jr, G. R.; Haas, Jr, J. L.

1983-01-01

83

DNA energy landscapes via calorimetric detection of microstate ensembles of metastable macrostates and triplet repeat diseases  

Microsoft Academic Search

Biopolymers exhibit rough energy landscapes, thereby allowing biological processes to access a broad range of kinetic and thermodynamic states. In contrast to proteins, the energy landscapes of nucleic acids have been the subject of relatively few experimental investigations. In this study, we use calorimetric and spectroscopic observables to detect, resolve, and selectively enrich energetically discrete ensembles of microstates within metastable

Jens Völker; Horst H. Klump; Kenneth J. Breslauer

2008-01-01

84

DNA Energy Landscapes via Calorimetric Detection of Microstate Ensembles of Metastable Macrostates and Triplet Repeat Diseases  

Microsoft Academic Search

Biopolymers exhibit rough energy landscapes, thereby allowing biological processes to access a broad range of kinetic and thermodynamic states. In contrast to proteins, the energy landscapes of nucleic acids have been the subject of relatively few experimental investigations. In this study, we use calorimetric and spectroscopic observables to detect, resolve, and selectively enrich energetically discrete ensembles of microstates within metastable

Jens Völker; Horst H. Klump; Kenneth J. Breslauer

2008-01-01

85

A calorimetric system based on the LKB 10700-1 flow microcalorimeter  

NASA Astrophysics Data System (ADS)

An electrically calibrated and computer-controlled apparatus based on the LKB 10700-1 flow microcalorimeter was set up and tested by determining the enthalpies of dilution of aqueous solutions of sucrose and HCl at 298.15 K. The obtained results are in good agreement with the corresponding reference values recommended in the literature. The quality of the calorimetric signal in terms of noise, linearity and baseline drift, and the instrument time constant were analyzed. Also investigated were the influences of the flow rate and of the viscosity of the calorimetric liquid on the position of the baseline. The new calibration system enables powers ~25 times smaller than those possible with the original one to be released inside the calorimetric cells. Electrical calibrations carried out with water as the sole calorimetric liquid indicated that the precision of the calibration constant, ?, quickly improved from ~9% to ~0.4% with the increase of the input power, P, from ~2 µW to ~50 µW, and stabilized at ~0.1% for P >= 100 µW. The calibration constant was also found to linearly increase with the flow rate of the calorimetric liquid and to vary by less than 1% over a period of eight months under similar experimental conditions. Finally a new experimental procedure for heat of dilution measurements, which combines calibration and experiment in a single run, was evaluated. This method allows a significant economy in experiment time with apparently no accuracy loss relative to the conventional procedure recommended in the literature.

Leskiv, Miroslav; Bernardes, Carlos E. S.; Minas da Piedade, Manuel E.

2009-07-01

86

PREFACE: XVI International Youth Scientific School 'Actual Problems of Magnetic Resonance and its Applications'  

NASA Astrophysics Data System (ADS)

In 1997, A S Borovik-Romanov, the Academician of RAS, and A V Aganov, the head of the Physics Department of Kazan State University, suggested that the 'School of Magnetic Resonance', well known in the Soviet Union, should recommence and be regularly held in Kazan. This school was created in 1968 by G V Scrotskii, the prominent scientist in the field of magnetic resonance and the editor of many famous books on magnetic resonance (authored by A Abragam, B. Bleaney, C. Slichter, and many others) translated and edited in the Soviet Union. In 1991 the last, the 12th School, was held under the supervision of G V Scrotskii. Since 1997, more than 600 young scientists, 'schoolboys', have taken part in the School meetings, made their oral reports and participated in heated discussions. Every year a competition among the young scientist takes place and the Program Committee members name the best reports, the authors of which are invited to prepare full-scale scientific papers. The XVI International Youth Scientific School 'Actual problems of the magnetic resonance and its application' in its themes is slightly different from previous ones. A new section has been opened this year: Coherent Optics and Optical Spectroscopy. Many young people have submitted interesting reports on optical research, many of the reports are devoted to the implementation of nanotechnology in optical studies. The XVI International Youth Scientific School has been supported by the Program of development of Kazan Federal University. It is a pleasure to thank the sponsors (BRUKER Ltd, Moscow, the Russian Academy of Science, the Dynasty foundation of Dmitrii Zimin, Russia, Russian Foundation for Basic Research) and all the participants and contributors for making the International School meeting possible and interesting. A V Dooglav, M Kh Salakhov and M S Tagirov The Editors

Salakhov, M. Kh; Tagirov, M. S.; Dooglav, A. V.

2013-12-01

87

Enthalpies of formation of the Al–Ni intermetallic compounds  

Microsoft Academic Search

The Al–Ni system has been investigated by direct reaction calorimetry at high temperatures. Enthalpies of formation of the intermetallic compounds AlNi3, AlNi, Al3Ni2, and Al3Ni were determined and compared with the available experimental values based on calorimetric and emf measurements and with the calculated values from theoretical models. X-ray powder diffraction (XRD) and electron probe microanalysis (EPMA) were used to

F. Z Chrifi-Alaoui; M Nassik; K Mahdouk; J. C Gachon

2004-01-01

88

Calorimetric effects during the ? ? ? transformation in Fe-Ni-Ti metastable alloys  

NASA Astrophysics Data System (ADS)

A calorimetric study of the reverse ? ? ? transformation has been carried out in five metastable Fe-Ni-Ti alloys. The amount of the ? phase in the initial samples is more than 50%. The exothermic processes of the decomposition of the ? and ? phases exceed the endothermic reactions of formation of the reverted austenite upon heating to the midpoint of the temperature interval of the reverse ? ? ? transformation. In the middle part of the interval in which the maximum rate of the transformation is recorded by the magnetometric method, the calorimetric curve does not exhibit thermal effects. This disagreement indicates the complex character of the transformation. At the finishing stage of the ? ? ? transformation, there is clearly detected an endothermic reaction.

Zemtsova, N. D.; Eremina, M. A.; Zavalishin, V. A.

2012-05-01

89

Calorimetric thermal-vacuum performance characterization of the BAe 80 K space cryocooler  

NASA Technical Reports Server (NTRS)

A comprehensive characterization program is underway at JPL to generate test data on long-life, miniature Stirling-cycle cryocoolers for space application. The key focus of this paper is on the thermal performance of the British Aerospace (BAe) 80 K split-Stirling-cycle cryocooler as measured in a unique calorimetric thermal-vacuum test chamber that accurately simulates the heat-transfer interfaces of space. Two separate cooling fluid loops provide precise individual control of the compressor and displacer heatsink temperatures. In addition, heatflow transducers enable calorimetric measurements of the heat rejected separately by the compressor and displacer. Cooler thermal performance has been mapped for coldtip temperatures ranging from below 45 K to above 150 K, for heatsink temperatures ranging from 280 K to 320 K, and for a wide variety of operational variables including compressor-displacer phase, compressor-displacer stroke, drive frequency, and piston-displacer dc offset.

Kotsubo, V. Y.; Johnson, D. L.; Ross, R. G., Jr.

1992-01-01

90

Calorimetric study of phase transitions in a liquid-crystal-based microemulsion  

Microsoft Academic Search

A lyotropic inverse micelle phase composed of water, thermotropic liquid-crystal octylcyanobiphenyl (8CB), and surfactant (DDAB) was studied by using high-resolution calorimetry on several mixtures with 3%, 8%, and 15% micelle concentration. Calorimetric results show strong depression of the isotropic to nematic (I-N) phase-transition temperature. Broad heat-capacity anomalies show the existence of a wide coexistence range of isotropic, nematic, and smectic-A

Zdravko Kutnjak; George Cordoyiannis; George Nounesis; Andrija Lebar; Slobodan Zumer

2005-01-01

91

First Calorimetric Measurement of OI-line in the Electron Capture Spectrum of $^{163}$Ho  

E-print Network

The isotope $^{163}$Ho undergoes an electron capture process with a recommended value for the energy available to the decay, $Q_{\\rm EC}$, of about 2.5 keV. According to the present knowledge, this is the lowest $Q_{\\rm EC}$ value for electron capture processes. Because of that, $^{163}$Ho is the best candidate to perform experiments to investigate the value of the electron neutrino mass based on the analysis of the calorimetrically measured spectrum. We present for the first time the calorimetric measurement of the atomic de-excitation of the $^{163}$Dy daughter atom upon the capture of an electron from the 5s shell in $^{163}$Ho, OI-line. The measured peak energy is 48 eV. This measurement was performed using low temperature metallic magnetic calorimeters with the $^{163}$Ho ion implanted in the absorber. We demonstrate that the calorimetric spectrum of $^{163}$Ho can be measured with high precision and that the parameters describing the spectrum can be learned from the analysis of the data. Finally, we dis...

Ranitzsch, P C -O; Wegner, M; Kempf, S; Fleischmann, A; Enss, C; Gastaldo, L; Herlert, A; Johnston, K

2014-01-01

92

Calorimetric determinations and theoretical calculations of polymorphs of thalidomide  

NASA Astrophysics Data System (ADS)

The analysis of the thermograms of thalidomide obtained for the two reported polymorphs ? and ? by differential scanning calorimetry (DSC) shows some inconsistencies that are discussed in the present work. The conception of a new polymorph form, named ? ?, allowed us to explain the observed thermal behavior more satisfactorily. This new polymorph shows enantiotropy with both ? and ? polymorphs, reflected in the unique endotherm obtained in the DSC-thermograms, when a heating rate of 10 °C/min is applied. Several additional experiments, such as re-melting of both polymorph forms, showed that there is indeed a new polymorph with an endotherm located between the endotherms of ? and ?. IR, Raman, and powder X-ray permit us to characterize the isolated compound, resulting from the re-melting of both polymorph forms. Mechanical calculations were performed to elucidate the conformations of each polymorph, and ab initio quantum chemical calculations were performed to determine the energy of the more stable conformers and the spatial cell energy for both polymorphs ? and ?. These results suggested a possible conformation for the newly discovered polymorph ? ?.

Lara-Ochoa, F.; Pérez, G. Espinosa; Mijangos-Santiago, F.

2007-09-01

93

Calorimetric study of smectic polymorphism in octyloxyphenyl-nitrobenzoyloxy benzoate + decyloxyphenyl-nitrobenzoyloxy benzoate mixtures  

Microsoft Academic Search

Binary mixtures of octyloxyphenyl-nitrobenzoyloxy benzoate (DB8ONO2) and decycloxyphenyl-nitrobenzoyloxy benzoate (DB10ONO2) exhibit a rich variety of smectic polymorphism. An ac calorimetric study has been carried out on six mixtures with mole percent X of the decyl homolog between 51 and 57, a range that includes the Sm-Ad-Nr-Sm-A1 point at X~=56. The sample with X=57 exhibits a first-order direct Sm-Ad-Sm-A1 transition, while

K. Ema; G. Nounesis; C. W. Garland; R. Shashidhar

1989-01-01

94

Presented at the ASHRAE Winter Meeting, Atlanta, GA, February 17-21, 1996, and published in the Proceedings. Calorimetric Measurements of Inward-Flowing Fraction  

E-print Network

LBL-37038 Mo-346 Presented at the ASHRAE Winter Meeting, Atlanta, GA, February 17-21, 1996, and published in the Proceedings. Calorimetric Measurements of Inward-Flowing Fraction for Complex Glazing Contract No. DE-AC03-76SF00098. #12;#12;Calorimetric Measurements of Inward-Flowing Fraction for Complex

95

Calorimetric Thermoelectric Gas Sensor for the Detection of Hydrogen, Methane and Mixed Gases  

PubMed Central

A novel miniaturized calorimeter-type sensor device with a dual-catalyst structure was fabricated by integrating different catalysts on the hot (Pd/?-Al2O3) and cold (Pt/?-Al2O3) ends of the device. The device comprises a calorimeter with a thermoelectric gas sensor (calorimetric-TGS), combining catalytic combustion and thermoelectric technologies. Its response for a model fuel gas of hydrogen and methane was investigated with various combustor catalyst compositions. The calorimetric-TGS devices detected H2, CH4, and a mixture of the two with concentrations ranging between 200 and 2000 ppm at temperatures of 100–400 °C, in terms of the calorie content of the gases. It was necessary to reduce the much higher response voltage of the TGS to H2 compared to CH4. We enhanced the H2 combustion on the cold side so that the temperature differences and response voltages to H2 were reduced. The device response to H2 combustion was reduced by 50% by controlling the Pt concentration in the Pt/?-Al2O3 catalyst on the cold side to 3 wt%. PMID:24818660

Park, Nam-Hee; Akamatsu, Takafumi; Itoh, Toshio; Izu, Noriya; Shin, Woosuck

2014-01-01

96

Calorimetric method for measuring high ultrasonic power using water as a heating material  

NASA Astrophysics Data System (ADS)

The present study shows the calorimetric method for measuring high ultrasonic power using water as the heating material. In recent years, at the National Metrology Institute of Japan (NMIJ), an ultrasonic power primary standard of from 1 mW to 15 W has been established by the radiation force balance (RFB) method. Conventionally, the RFB method is widely used for ultrasonic power measurement, but this method is not suitable for very high power measurement due to thermal damages to the absorbing targets. High power ultrasonic standards, however, are being required by medical HITU measurements and in the sonochemistry industry. In order to meet these requirements, we have started to develop an ultrasonic power standard between 15 W and 200 W. Our final goal is an ultrasonic power standard of up to 500 W. The calorimetric method is an alternative ultrasonic power measurement method to the RFB method. We have adopted this method and use water as the heating material. Water has excellent features as a standard material, because the physical properties of water are well known. In the present study, we present an experimental system and the results for an ultrasonic power standard of up to 100 W. The measured ultrasonic power agreed well with the NMIJ primary standard up to 25 W.

Kikuchi, T.; Uchida, T.

2011-02-01

97

Calorimetric thermoelectric gas sensor for the detection of hydrogen, methane and mixed gases.  

PubMed

A novel miniaturized calorimeter-type sensor device with a dual-catalyst structure was fabricated by integrating different catalysts on the hot (Pd/?-Al2O3) and cold (Pt/?-Al2O3) ends of the device. The device comprises a calorimeter with a thermoelectric gas sensor (calorimetric-TGS), combining catalytic combustion and thermoelectric technologies. Its response for a model fuel gas of hydrogen and methane was investigated with various combustor catalyst compositions. The calorimetric-TGS devices detected H2, CH4, and a mixture of the two with concentrations ranging between 200 and 2000 ppm at temperatures of 100-400 °C, in terms of the calorie content of the gases. It was necessary to reduce the much higher response voltage of the TGS to H2 compared to CH4. We enhanced the H2 combustion on the cold side so that the temperature differences and response voltages to H2 were reduced. The device response to H2 combustion was reduced by 50% by controlling the Pt concentration in the Pt/?-Al2O3 catalyst on the cold side to 3 wt%. PMID:24818660

Park, Nam-Hee; Akamatsu, Takafumi; Itoh, Toshio; Izu, Noriya; Shin, Woosuck

2014-01-01

98

Breit-Pauli R-Matrix Calculations for L-Shell Atomic Processes in fe XVI, fe XVII, and XVIII  

NASA Astrophysics Data System (ADS)

We report extensive relativistic close coupling R-matrix calculations of L-shell atomic processes in Fe XVI, Fe XVII, and Fe XVIII. In particular these include photoionization, recombination, transition probabilities, and electron impact excitation of Ne-like Fe XVII. The collisional calculations employ employ the Breit-Pauli R-matrix method and a 89-level eigenfunction expansion including up to n = 4 levels of Fe XVII. Significant resonance enhancement of the collision strengths of forbidden and intercombination is demonstrated. The present results differ from all previous calculations, heretofore without detailed resonance structures, and should help resolve longstanding discrepancies. In particular, the present line ratios of three benchmark diagnostic lines 3C, 3D, and 3E at 15.014, 15.265, and 15.456 Årespectively, are in excellent agreement with two independent measurements on Electron-Beam-Ion-Traps [Laming et al., Astrophys. J 545, L161 (2000) and Brown et al., Astrophys. J 502, 1015 (1998)]. The strong energy dependence due to resonances in these and other cross sections is demonstrated. The new theoretical results should be of considerable interest in uc(x-ray) plasma diagnostics of laboratory and astrophysical sources. Relativistic R-matrix calculations for photoionization and recombination of Fe XVI and Fe XVII are in progress. Partial support from the NSF and NASA is acknowledged.

Chen, Guo Xin; Nahar, Sultana; Pradhan, Anil; Zhang, Honglin

2002-05-01

99

20 CFR 408.931 - How much will we withhold from your title II and title XVI benefits to recover a title VIII...  

Code of Federal Regulations, 2010 CFR

...the monthly title II benefits payable for that month...the case of title XVI benefits, an amount no greater than the lesser of the benefit payable for that month...including such monthly benefit but excluding payments...also made from title II benefits and excluding...

2010-04-01

100

20 CFR 404.535 - How much will we withhold from your title VIII and title XVI benefits to recover a title II...  

Code of Federal Regulations, 2010 CFR

(b)(1) We will collect the overpayment from current monthly benefits due in a month under title VIII and title XVI by withholding the lesser of the amount of the entire overpayment balance or: (i) 10 percent of the monthly title VIII benefits payable for that month...

2010-04-01

101

The Bayer Facts of Science Education XVI: "US STEM Workforce Shortage--Myth or Reality? Fortune 1000 Talent Recruiters on the Debate"  

ERIC Educational Resources Information Center

A major debate is currently underway in the USA about whether there is, in fact, a science, technology, engineering and mathematics (STEM) workforce shortage in the country or not. This is the subject of the "Bayer Facts of Science Education XVI: US STEM Workforce Shortage--Myth or Reality? Fortune 1000 Talent Recruiters on the Debate."…

Journal of Science Education and Technology, 2014

2014-01-01

102

forumA publication of the Academic Senate, California State University, FullertonVolume XVI, Number 2, Spring 2001 An Interview with  

E-print Network

of air pollution. The story that follows has two threads: how and why the air has become so much cleaner. Background Southern Californian's live in the epicenter of air pollution. We have the dubious distinctionforumA publication of the Academic Senate, California State University, FullertonVolume XVI, Number

de Lijser, Peter

103

Single-walled carbon nanotubes in superacid: X-ray and calorimetric evidence for partly ordered H2SO4  

E-print Network

Single-walled carbon nanotubes in superacid: X-ray and calorimetric evidence for partly ordered H2. Smalley Center for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, USA Received 7 in the presence of single-walled carbon nanotubes SWNTs . X-ray scattering from aligned fibers immersed in acid

Natelson, Douglas

104

Premelting at fusion of titanite CaTiSiO5: a calorimetric study  

NASA Astrophysics Data System (ADS)

An extensive anomalously rapid increase of relative enthalpy H( T) - H(298 K) of crystalline CaTiSiO5 was observed by means of high-temperature drop calorimetry when melting point is approached. X-ray diffraction analysis of the quenched products after drop in calorimeter shows that this effect is related to premelting. The determined excess enthalpy of crystals near the melting point reaches up to 115 kJ mol-1, that is about 82 % of the total enthalpy of melting, indicating that the premelting effect reflects configurational changes in the bulk of the crystals rather than a surface melting or any other type of partial melting. The obtained results support the presumption that calorimetrically measured premelting effect in titanite reflects the energy-consuming temperature-induced disordering of the framework elements, Si and Ti, which are strongly bonded to oxygen.

Nerád, I.; Mikšíková, E.; Kosa, L.; Adamkovi?ová, K.

2013-07-01

105

Transport and calorimetric studies on CeNi2Al3  

NASA Astrophysics Data System (ADS)

Transport and calorimetric properties of Kondo lattice system CeNi2Al3 are reported. CeNi2Al3 shows good agreement with Grand Kadowaki-Woods relation with degeneracy of the quasi-particle N=6. The nonmagnetic nature of CeNi2Al3 is evident from resistivity measurement even though magnetic elements Ce and Ni are present. Three signatures, deviation from the normal metallic behaviour in resistivity above 140 K, relatively low charge carrier concentration (1021 cm−3) and energy gap Eg~11.6 meV obtained from two band model shed light on the most basic notions related to the semimetal nature of CeNi2Al3.

Y, Sankararao; Shanmukharao Samatham, S.; D, Venkateshwarlu; Gangrade, Mohan; Ganesan, V.

2014-09-01

106

Calorimetric study on the effect of 60Co ?-rays on the growth of microorganisms  

NASA Astrophysics Data System (ADS)

Using a calorimeter equipped with 24 sample units, the heat evolution from growing Saccharomyces cerevisiae, Escherichia coli and spores of Bacillus pumilus and Bacillus stearothermophilus was detected in the form of growth thermograms. Irradiation with 60Co ?-rays affected the growth pattern, which was used for a quantitative analysis of the effect on microorganisms. Irradiation of B. pumilus and B. stearothermophilus spores led to dose-dependent delays in growth, indicating a bactericidal effect. In case of 60Co ?-irradiated S. cerevisiae, a dose-dependent reduction of the growth rate constant was observed together with the retardation in growth, indicating a combination of bactericidal and bacteriostatic effects. An equation to determine the number of survivors on the basis of the retardation in growth t? and the growth rate constant ? was developed, which proved the opportunity to use the calorimetric technique in predictive microbiology.

Wirkner, Sandra; Takahashi, Katsutada; Furuta, Masakazu; Hayashi, Toshio

2002-03-01

107

Calorimetric Determinations of the Heat and Products of Detonation for Explosives: October 1961 to April 1982  

NASA Astrophysics Data System (ADS)

This report is a compilation of heat-of-detonation and product-composition data obtained at Lawrence Livermore National Laboratory during the last 21 years. In each determination, a 25-g high-explosive charge was detonated in a bomb calorimeter; a complete calorimetric measurement was made in 1 to 2 h with a precision of 0.3%. Data were interpreted using thermodynamic and hydrodynamic computer calculations. For unconfined or lightly confined charges, the released energy is largely retained in the products, which are subsequently shocked considerably off the Chapman-Jouguet isentrope by reflections from the bomb wall. For heavily confined charges, the detonation energy is largely converted to kinetic and internal energy of the confining case, and the products expand with minimal reshock along the Chapman-Jouguet isentrope.

Ornellas, D. L.

1982-04-01

108

Idebenone loaded solid lipid nanoparticles: calorimetric studies on surfactant and drug loading effects.  

PubMed

In this study we prepared solid lipid nanoparticles (SLN), by the phase inversion temperature (PIT) method, using cetyl palmitate as solid lipid and three different non-ionic emulsifiers of the polyoxyethylene ethers family (ceteth-20, isoceteth-20, oleth-20). These SLN were loaded with different amount of idebenone (IDE), an antioxidant drug useful in the treatment of neurodegenerative diseases and skin oxidative damages. The differential scanning calorimetry (DSC) was employed to evaluate the effects of the different emulsifiers and the different amounts of drug loaded on the thermotropic behavior of SLN and to investigate how the drug was arranged into these nanoparticles. The IDE seemed to be located into different regions of the SLN depending on its concentration and on the surfactant used. The results of this study suggest that the calorimetric studies performed on SLN could provide valuable information to optimize SLN design and drug release from these carriers. PMID:24845103

Sarpietro, Maria Grazia; Accolla, Maria Lorena; Puglisi, Giovanni; Castelli, Francesco; Montenegro, Lucia

2014-08-25

109

Rapid discrimination of DNA strands using an opto-calorimetric microcantilever sensor.  

PubMed

A rapid technique for quantitative detection and discrimination of DNA strands without using immobilized probe molecules is demonstrated using an opto-calorimetric, self-powered sensor based on a Pb(Zr0.52Ti0.48)O3 (PZT) microcantilever. Microcalorimetric infrared (IR) spectroscopy provides excellent chemical selectivity based on the unique molecular vibrational characteristics of each nucleotide in the mid IR region. The piezoelectric and pyroelectric properties of the PZT microcantilever were exploited in the quantitative detection and discrimination of adsorbed DNA strands with their spectral characteristics. We report the unique spectral characteristics of different DNA nucleotides that are monitored by wavelength-dependent temperature variations for different relative molar ratio of each nucleotide. This approach offers a fast, label-free technique which is highly sensitive and selective for the detection of single nucleotide differences in DNA strands and has the potential to be used as a rapid prescreening biosensor for various biomolecules. PMID:25300415

Lee, Dongkyu; Hwang, Kyo Seon; Kim, Seonghwan; Thundat, Thomas

2014-12-21

110

Nano-Calorimetric Studies of Polymeric Phase Transitions in Confined Geometries  

NASA Astrophysics Data System (ADS)

Despite the immense technological significance of phase transitions and thermodynamic properties of polymer thin films and other nano-structures, several fundamental issues remain unresolved. This is partly due to insufficient sensitivity and high thermal time constants of conventional thermal characterization techniques, e.g. differential scanning calorimetry (DSC). On the other hand, the sensitivity of nano-calorimetric devices (.1microW-1nW) has been demonstrated to be two-three orders of magnitude better than conventional DSC systems. Moreover, internal time constants on the order of 1 ms are readily achievable. In this work, MEMS fabrication technology is used to develop ultra-sensitive thin film differential scanning nano-calorimeters. Design optimization of the nano-calorimeter is achieved by numerical finite element simulation of heat transfer across its various constituents. Glass transition and melting behavior of polystyrene and polyethylene oxide thin films are studied using the nano-calorimeter.

Alizadeh, Azar; Zribi, Anis; Ganti, Surya; Sharma, Pradeep; Conway, Ken; Tsakalakos, Loucas; Malenfant, Patrick R. L.; Teetsov, Julie

2003-03-01

111

Total hemispherical emittance measured at high temperatures by the calorimetric method  

NASA Technical Reports Server (NTRS)

A calorimetric vacuum emissometer (CVE) capable of measuring total hemispherical emittance of surfaces at elevated temperatures was designed, built, and tested. Several materials with a wide range of emittances were measured in the CVE between 773 to 923 K. These results were compared to values calculated from spectral emittance curves measured in a room temperature Hohlraum reflectometer and in an open-air elevated temperature emissometer. The results differed by as much as 0.2 for some materials but were in closer agreement for the more highly-emitting, diffuse-reflecting samples. The differences were attributed to temperature, atmospheric, and directional effects, and errors in the Hohlraum and emissometer measurements (plus or minus 5 percent). The probable error of the CVE measurements was typically less than 1 percent.

Difilippo, Frank; Mirtich, Michael J.; Banks, Bruce A.; Stidham, Curtis; Kussmaul, Michael

1989-01-01

112

Emittance characterization of thermal control paints, coatings and surfaces using a calorimetric technique  

NASA Technical Reports Server (NTRS)

Thermal control surfaces are used in every spacecraft thermal management system to dissipate heat through radiant heat transfer. This paper describes the thermal performance of several thermal control paints, coatings, and surfaces, as characterized by a calorimetric vacuum emissometer. The emissometer is designed to measure the functional emittance of a surface based on heat transfer from an underlying substrate to the surface and from the surface or near surface to a surrounding cold wall. Emittance measurements were made between 200 and 350 K. Polished aluminum, used here as a standard, was found to have a total hemispherical emittance of 0.06, as expected. A velvet black paint, also used here as a standard, was found to have an emittance of 0.94 at room temperature. Other surfaces of interest included a polyurethane-based black paint designated Z-306, a highly polished 316L stainless steel, and an atomic oxygen beam-textured carbon-carbon composite.

Jaworske, Donald A.

1994-01-01

113

Simulation work on calorimetric energy resolution for the TAC-PF Detector  

NASA Astrophysics Data System (ADS)

According to the Turkish Accelerator Center (TAC) project, a tau-charm factory is proposed based on colliding a 1 GeV electron beam against a 3.5 GeV positron beam. The Particle Factory (TAC-PF) detector will be constructed for the detection of the producing particles from this collision. PbWO4 and CsI(Tl) crystals are considered for the construction of the electromagnetic calorimeter. The photons generated from incident particles in the crystal material are detected by Avalanche photodiodes (APD) or PIN photodiodes placed at the end of the crystal. In this work, the contribution to the calorimetric energy resolution from both the shower fluctuations in the crystal and photoelectron statistics in the detectors have been simulated for PbWO4-APD and PbWO4-PIN combinations.

Tapan, Ilhan; Kocak, Fatma

2012-12-01

114

Reversibility and isotope effect of the calorimetric glass --> liquid transition of low-density amorphous ice.  

PubMed

We here report differential scanning calorimetry (DSC) scans recorded by repeatedly heating the H(2)O (D(2)O) low density amorph (LDA) which was made by isothermal decompression of very high-density amorphous ice (VHDA) at 140 K from 1.1 to 0.006 GPa. These DSC scans show a glass --> liquid transition endotherm with an onset temperature (T(g)) of approximately 137 (140) K at a heating rate of 30 K min(-1) accompanied by an increase in heat capacity of approximately 1.7 (1.5) J K(-1) mol(-1). We establish the reversibility of this effect by thermally cycling between its glassy state below 137 K and its highly viscous liquid state at 149 K. All calorimetric signatures, including H/D isotope effect, are highly similar to the signatures in hyperquenched glassy water (HGW). We argue that the observation of almost identical calorimetric traces for HGW and LDA implies that there is no need to reassign HGWs T(g) to higher temperatures provided that the viscous liquid state connected to both LDA and HGW behaves as an ideally "strong" liquid in the Angell classification. We furthermore show that LDA prepared by isothermal decompression of VHDA is more crystallization-resistant than LDA made from high-density amorphous ice (HDA) by isobaric warming. We suggest that the former route via VHDA removes "nanocrystalline remnants" in LDA which are still present in the latter after pressure-amorphization of hexagonal ice to HDA at 77 K. PMID:20066356

Elsaesser, Michael S; Winkel, Katrin; Mayer, Erwin; Loerting, Thomas

2010-01-21

115

Concurrent calorimetric and interferometric studies of steady-state natural convection from miniaturized horizontal single plate-fin systems and plate-fin arrays  

E-print Network

Concurrent calorimetric and interferometric studies have been conducted to investigate the effect that reduction of the base-plate dimensions has on the steady-state performance of the rate of natural convection heat ...

Harahap, Filino

116

New methodology for simultaneous volumetric and calorimetric measurements: Direct determination of ?p and Cp for liquids under pressure  

NASA Astrophysics Data System (ADS)

A new batch cell has been developed to measure simultaneously both isobaric thermal expansion and isobaric heat capacity from calorimetric measurements. The isobaric thermal expansion is directly proportional to the linear displacement of an inner flexible below and the heat capacity is calculated from the calorimetric signal. The apparatus used was a commercial Setaram C-80 calorimeter and together with this type of vessels can be operated up to 20 MPa and in the temperature range of 303.15-523.15 K, In this work, calibration was carried out using 1-hexanol and subsequently both thermophysical properties were determined for 3-pentanol, 3-ethyl-3-pentanol, and 1-octanol at atmospheric pressure, 5 and 10 MPa, and from 303.15 to 423.15 K in temperature. Finally experimental values were compared with the literature in order to validate this new methodology, which allows a very accurate determination of isobaric thermal expansion and isobaric heat capacity.

Casás, L. M.; Plantier, F.; Bessières, D.

2009-12-01

117

Calorimetric determination of fragility in glass forming liquids: T(f) vs. T(g-onset) methods.  

PubMed

The calorimetric determination of the fragility m-index is compared using the T f and T g-onset methods for typical metallic and molecular glass forming systems of Pd39Ni10Cu30P21, glycerol, triacetin and propylene carbonate. The results are evaluated by referring to the standard m-values determined from the kinetic measurements of the viscosity or structural relaxation time in the supercooled liquid regimes. The m-indexes derived from the T f method are found to generally agree well with the kinetic measurements for all the systems. However, a large deviation is shown between the m-indexes calculated with the T g-onset method and the kinetic results for the fragile liquids of triacetin and propylene carbonate, indicating the calorimetric determination of the fragility m-indexes in terms of the T f method produces less uncertainty. PMID:24965151

Chen, Zeming; Li, Zijing; Zhang, Yaqi; Liu, Riping; Tian, Yongjun; Wang, Li-Min

2014-06-01

118

Calorimetric output power measurements on a CW 20 kW 7.16 GHz microwave transmitter  

NASA Technical Reports Server (NTRS)

A calorimetric measurement technique developed for NASA's Deep Space Network (DSN) transmitters that does not require data on the coolant's thermal parameters is described. Calibration of the measurement system is achieved by measuring the DC input power to the klystron and relating coolant temperature increases to this known power dissipation. Agreement between calorimetric and electrical measurements of total system power was good, the difference being less than 2 percent. The operation of the system was not greatly affected by the composition of the coolant, which was varied from pure water to 40 percent ethylene glycol by mass. Good accuracy was also shown at output power levels, which varied over a 3.6:1 range.

Perez, Raul M.; Conroy, Bruce L.

1991-01-01

119

Measurement and Modeling of Inner-Shell Satellites of Na-like Fe XVI between 14.5 ?A and 18 ?A  

SciTech Connect

We have used the University of California Lawrence Livermore National Laboratory's EBIT-I electron beam ion trap to perform measurements of the wavelengths and relative intensities of the X-ray lines from inner-shell satellite transitions in sodium-like Fe XVI. The measurements were carried out with high-resolution crystal and grating spectrometers and covered the 14.5-18 {angstrom} wavelength band. Contrary to predicted line strengths and positions found in the literature, our results show that the strongest inner-shell satellites of Fe XVI are located near 15.2 {angstrom}. This is near the location of the 3d {yields} 2p intercombination line in Fe XVII. Calculations using the Flexible Atomic Code are presented, which agree well with the EBIT-I measurements.

Graf, A; Beiersdorfer, P; Brown, G V; Gu, M F

2007-09-10

120

Differential scanning calorimetric evaluation of human meibomian gland secretions and model lipid mixtures: transition temperatures and cooperativity of melting  

PubMed Central

Meibomian gland secretions (or meibum) are produced by holocrine meibomian glands and are secreted in melted form onto the ocular surface of humans and animals to form a protective tear film lipid layer (TFLL). Its protective effect strongly depends on the composition and, hence, thermotropic behavior of meibum. The goal of our study was to quantitatively evaluate the melting characteristics of human meibum and model lipid mixtures using differential scanning microcalorimetry. Standard calorimetric parameters, e.g. changes in calorimetric enthalpy, transition temperatures T(m), cooperativity of melting etc. were assessed. We found that thermotropic behavior of meibum resembled that of relatively simple mixtures of unsaturated wax esters, but showed a lower change in calorimetric enthalpy, which can be indicative of a looser packing of lipids in meibum compared with pure standards and their simple mixtures. The cooperativity of melting of meibomian lipids was comparable to that of an equimolar mixture of four oleic-acid based wax esters. We demonstrated that the phase transitions in meibum start at about 10 to 15 °C and end at 35-36 °C, with T(m) being about 30 °C. The highly asymmetrical shape of the thermotropic peak of meibum is important for the physiology and biophysics of TFLL. PMID:23578711

Lu, Hua; Wojtowicz, Jadwiga C.; Butovich, Igor A.

2013-01-01

121

Effect of Temperature on Xylanase II from Trichoderma reesei QM 9414: A Calorimetric, Catalytic, and Conformational Study  

PubMed Central

The secondary structure of xylanase II from Trichoderma reesei is lost in an apparent irreversible cooperative process as temperature is increased with a midpoint transition of 58.8 ± 0.1°C. The shift of the spectral centre of mass above 50°C is also apparently cooperative with midpoint transition of 56.3 ± 0.2°C, but the existence of two isofluorescent points in the fluorescence emission spectra suggests a non-two-state process. Further corroboration comes from differential scanning calorimetry experiments. At protein concentrations ?0.56?mg·mL?1 the calorimetric transition is reversible and the data were fitted to a non-two-state model and deconvoluted into six transitions, whereas at concentrations greater than 0.56?mg·mL?1 the calorimetric transition is irreversible with an exothermic contribution to the thermogram. The apparent Tm increased linearly with the scan rate according to first order inactivation kinetics. The effect of additives on the calorimetric transition of xylanase is dependent on their nature. The addition of sorbitol transforms reversible transitions into irreversible transitions while stabilizing the protein as the apparent Tm increases linearly with sorbitol concentration. d-Glucono-1,5-lactone, a noncompetitive inhibitor in xylanase kinetics, and soluble xylan change irreversible processes into reversible processes at high protein concentration.

Lopez, Gloria

2014-01-01

122

Compound Interest  

NSDL National Science Digital Library

Albert Einstein called compound interest the 8th wonder of the world. Find out why compound interest and the time value of money are so important. What is Interest Click on the following link to read about the different types of interest. Loans and Interest So why learn about compound interest? Using time and interest to your advantage, you can make more money than you have ever dreamed of. See how the time value of ...

Riches, Ms.

2007-10-16

123

The Calorimetric Electron Telescope (CALET) for High Energy Astroparticle Physics on the International Space Station  

NASA Astrophysics Data System (ADS)

The Calorimetric Electron Telescope, CALET, space experiment, currently under development by Japan in collaboration with Italy and the United States, will measure the flux of Cosmic Ray electrons (and positrons) t o 20 TeV, gamma rays to 10 TeV , nuclei with Z=1 to 40 up to 1,000 TeV, and Gamma-ray bursts in the 7 keV- 10 MeV energy range during a five year mission. These measurements are essential to investigate possible nearby astrophysical sources of high energy electrons, study the details of galactic particle propagation and search for dark matter signatures. The main detector of Calet, the Calorimeter, consists of a module to identify the particle charge, followed by a thin imaging calorimeter (3 radiation lengths) with tungsten plates interleaving scintillating fiber planes, and a thick energy measuring calorimeter (27 radiation lengths) composed of lead tungstate logs. The Calorimeter has the depth, imaging capabilities and energy resolution necessary for excellent separation between hadrons, electrons and gamma rays. The instrument is currently being prepared for launch, during the Japan Fiscal Year (April, 2014- March, 2015) time frame, to the International Space Station (ISS) for installation on the Japanese Experiment Module - Exposure Facility (JEM-EF).

Torii, Shoji

124

Higher order inclusion complexes and secondary interactions studied by global analysis of calorimetric titrations.  

PubMed

This paper investigates the use of isothermal titration calorimetry (ITC) as a tool for studying molecular systems in which weaker secondary interactions are present in addition to a dominant primary interaction. Such systems are challenging since the signal pertaining to the stronger primary interaction tends to overshadow the signal from the secondary interaction. The methodology presented here enables a complete and precise thermodynamic characterization of both the primary and the weaker secondary interaction, exemplified by the binding of ?-cyclodextrin to the primary and secondary binding sites of the bile salt glycodeoxycholate. Global regression analysis of calorimetric experiments at various concentrations and temperatures provide a precise determination of ?H, ?G°, and ?C(p) for both binding sites in glycodeoxycholate (K1 = 5.67 ± 0.05 × 10(3) M(-1), K2 = 0.31 ± 0.02 × 10(3) M(-1)). The results are validated by a (13)C NMR titration and negative controls with a bile salt with no secondary binding site (glycocholate) (K = 2.96 ± 0.01 × 10(3) M(-1)). The method proved useful for detailed analysis of ITC data and may strengthen its use as a tool for studying molecular systems by advanced binding models. PMID:22292412

Schönbeck, Christian; Holm, René; Westh, Peter

2012-03-01

125

Differential scanning calorimetric studies of nickel-titanium rotary endodontic instruments after simulated clinical use.  

PubMed

Differential scanning calorimetric (DSC) analyses have been performed between -130 degrees and 100 degrees C on single-segment specimens obtained from ProFile and Lightspeed nickel-titanium rotary endodontic instruments in the as-received condition and after one, three, and six periods of simulated clinical use in extracted teeth. The DSC analyses showed that both brands of instruments were always in the superelastic condition, although the enthalpy values for the transformation from martensitic NiTi to austenitic NiTi were much smaller for the Lightspeed instruments. Simulated clinical use had no evident effect upon this transformation for both brands, which is attributed to insufficient mechanical deformation of the instruments. There were substantial differences in the enthalpy change associated with the transformation from martensitic NiTi to austenitic NiTi for test segments from different positions along the shafts of the instruments and for as-received instruments from two different batches that were analyzed in this study and a previous study. These differences are attributed to variations in work hardening along the shaft during instrument fabrication and to processing differences during production of the two batches of each instrument brand. PMID:12470023

Brantley, W A; Svec, T A; Iijima, M; Powers, J M; Grentzer, T H

2002-11-01

126

Optical and Calorimetric Studies of Cholesterol-Rich Filamentous, Helical Ribbon and Crystal Microstructures (abstract)  

NASA Astrophysics Data System (ADS)

Formation of biological self-assemblies at all scales is a focus of studies in fields ranging from biology to physics to biomimetics. Understanding the physico-chemical properties of these self-assemblies may lead to the design of bio-inspired structures and technological applications. Here we examine self-assembled filamentous, helical ribbon, and crystal microstructures formed in chemically defined lipid concentrate (CDLC), a model system for cholesterol crystallization in gallbladder bile. CDLC consists of cholesterol, bilayer-forming amphiphiles, micelle-forming amphiphiles, and water. Phase contrast and differential interference contrast (DIC) microscopy indicate the presence of three microstructure types in all samples studied, and allow for an investigation of the structures' unique geometries. Additionally, confocal microscopy is used for qualitative assessment of surface and internal composition. To complement optical observations, calorimetric (differential-scanning and modulation) experiments, provide the basis for an in-depth understanding of collective and individual thermal behavior. Observed ``transition'' features indicate clustering and ``straightening'' of helical ribbons into short, increasingly thickening, filaments that dissolve with increasing temperature. These results suggest that all microstructures formed in CDLC may coexist in a metastable chemical equilibrium. Further investigation of the CDLC thermal profile should uncover the process of cholesterol crystallization as well as the unique design and function of microstructures formed in this system.

Miroshnikova, Y. A.; Elsenbeck, M.; Kashuri, K.; Iannacchione, G. S.; Zastavker, Y. V.

2009-04-01

127

Interaction of methotrexate, folates, and pyridine nucleotides with dihydrofolate reductase: calorimetric and spectroscopic binding studies.  

PubMed Central

The thermodynamic parameters, deltaG, deltaH, and deltaS characterizing the tight binding of methotrexate, folates, and pyridine nucleotides to chicken liver dihydrofolate reductase (5,6,7,8-tetrahydrofolate: NADP+ oxidoreductase, EC 1.5.1.3) have been determined from calorimetric and fluorescence measurements. At 25 degrees the binding of NADPH and NADP+ is characterized by small negative enthalpies and large positive entropies whereas the binding of the folates and methotrexate is accompanied by large negative enthalpies and small negative entropies. In addition, the enthalpy of methotrexate-enzyme interaction demonstrates a proton transfer associated with binding; this is not the case with folate and dihydrofolate, thus confirming the conclusions drawn from the observed difference spectra characteristic of the interaction of methotrexate and substrates with the enzyme. The implications of these results are discussed in terms of the nature of the binding process, conformational changes in the enzyme, and the nature of the active site region. PMID:28523

Subramanian, S; Kaufman, B T

1978-01-01

128

Calorimetric and theoretical study of the interaction between some saccharides and sodium halide in water.  

PubMed

Dilution enthalpies and mixing enthalpies of sodium halide and some saccharides (glucose, galactose, xylose, arabinose, fructose, and sucrose) in aqueous solution were determined by calorimetric measurements at 298.15 K. The values were used to determine enthalpic pair interaction parameters. Combined with Gibbs energy pair parameters, entropic pair interaction parameters were also obtained. Theoretical calculations at the B3LYP/6-311++G(d,p) level were carried out to provide the information of structures and thermodynamic functions. The information reveals the thermodynamic essence of the interactions between sodium halide and saccharides in aqueous solutions. The experimental results and theoretical calculations show that the sign of enthalpic pair interaction parameter 2?h(ES) is determined by the direct interaction between saccharides and ions, whereas the difference in value of 2?h(ES) for different saccharides or electrolytes depends on the partial dehydration of saccharides or anions in aqueous solution. The difference in value of entropic pair interaction parameters depends partly on the different dominant interactions in the process of partial dehydration of saccharides or ions. An enthalpy-entropy compensation relationship was observed for the sodium bromide-aldopyranose-water systems. Remarkably, it can be conjectured that the hydration entropy of glucose is lower than for other monosaccharides. Perhaps it is one of the reasons why glucose plays an important role in living organisms rather than other monosaccharides. PMID:22779908

Zhuo, Kelei; Fu, Yingyi; Bai, Guangyue; Wang, Jianji; Yan, Haike; Wang, Hanqing

2012-08-23

129

Idebenone loaded solid lipid nanoparticles interact with biomembrane models: calorimetric evidence.  

PubMed

The knowledge of the interactions between solid lipid nanoparticles (SLN) and cell membranes is important to develop effective carrier systems for drug delivery applications. Loading idebenone (IDE), an antioxidant drug useful in the treatment of neurodegenerative diseases, into SLN improves IDE antioxidant activity in in vitro biological studies, but the mechanism by which IDE permeation through the blood-brain barrier (BBB) occurs are still unclear. Therefore, in this research, unloaded and IDE loaded SLN interaction with biomembrane models, consisting of dimyristoylphosphatidylcholine multilamellar vesicles (MLV), were studied by differential scanning calorimetry (DSC). In the experiments performed, unloaded and IDE loaded SLN where incubated with the biomembrane models and their interactions were evaluated through the variations in their calorimetric curves. The results of our DSC studies indicated that the SLN under investigation were able to go inside the phospholipid bilayers with a likely localization in the outer bilayers of the MLV from where they moved toward the inner layers by increasing the contact time between SLN and MLV. Furthermore, IDE loaded SLN were able to release IDE into the biomembrane model, thus facilitating IDE penetration into the bilayers while free IDE showed only a low ability to interact with this model of biomembranes. Our results suggest that these SLN could be regarded as a promising drug delivery system to improve IDE bioavailability and antioxidant activity. PMID:22894135

Montenegro, Lucia; Ottimo, Sara; Puglisi, Giovanni; Castelli, Francesco; Sarpietro, Maria Grazia

2012-09-01

130

Optical and Calorimetric Studies of Cholesterol-Rich Filamentous, Helical Ribbon and Crystal Microstructures  

SciTech Connect

Formation of biological self-assemblies at all scales is a focus of studies in fields ranging from biology to physics to biomimetics. Understanding the physico-chemical properties of these self-assemblies may lead to the design of bio-inspired structures and technological applications. Here we examine self-assembled filamentous, helical ribbon, and crystal microstructures formed in chemically defined lipid concentrate (CDLC), a model system for cholesterol crystallization in gallbladder bile. CDLC consists of cholesterol, bilayer-forming amphiphiles, micelle-forming amphiphiles, and water. Phase contrast and differential interference contrast (DIC) microscopy indicate the presence of three microstructure types in all samples studied, and allow for an investigation of the structures' unique geometries. Additionally, confocal microscopy is used for qualitative assessment of surface and internal composition. To complement optical observations, calorimetric (differential-scanning and modulation) experiments, provide the basis for an in-depth understanding of collective and individual thermal behavior. Observed ''transition'' features indicate clustering and ''straightening'' of helical ribbons into short, increasingly thickening, filaments that dissolve with increasing temperature. These results suggest that all microstructures formed in CDLC may coexist in a metastable chemical equilibrium. Further investigation of the CDLC thermal profile should uncover the process of cholesterol crystallization as well as the unique design and function of microstructures formed in this system.

Miroshnikova, Y. A.; Elsenbeck, M.; Zastavker, Y. V. [Franklin W. Olin College of Engineering, Needham, MA (United States); Kashuri, K; Iannacchione, G. S. [Worcester Polytechnic Institute, Worcester, MA (United States)

2009-04-19

131

Calorimetric measurement of electron energy deposition in extended media. Theory vs experiment  

SciTech Connect

A new calorimetric technique has been developed for measuring electron energy deposition profiles in one dimension. The experimental procedures and theoretical analyses required in the application of the new method are reviewed. Extensive results are presented for electron energy deposition profiles in semi-infinite homogeneous and multilayer configurations. These data cover a range of elements from beryllium through uranium at source energies from 0.3 to 1.0 MeV (selected data at 0.5 and 0.1 MeV) and at incident angles from 0/sup 0/ to 60/sup 0/. In every case, the experimental profiles are compared with the predictions of a coupled electron/photon Monte Carlo transport code. Overall agreement between theory and experiment is very good. However, there appears to be a tendency for the theoretical profiles to be higher near the peaks and lower near the tails, especially in high-Z materials. There is also a discrepancy between theory and experiment in low-Z materials near high-Z/low-Z interfaces.

Lockwood, G.J.; Ruggles, L.E.; Miller, G.H.; Halbleib, J.A.

1980-01-01

132

Crop changes from the XVI century to the present in a hill/mountain area of eastern Liguria (Italy)  

PubMed Central

Background Chronological information on the composition and structure of agrocenoses and detailed features of land cover referring to specific areas are uncommon in ethnobotanical studies, especially for periods before the XIX century. The aim of this study was to analyse the type of crop or the characteristics of soil cover from the XVI century to the present. Methods This diachronic analysis was accomplished through archival research on the inventories of the Parish of St. Mary and those of the Municipality of Pignone and from recent surveys conducted in an area of eastern Liguria (Italy). Results Archival data revealed that in study area the primary means of subsistence during the last five centuries, until the first half of the XX century, was chestnuts. In the XVIII and XIX centuries, crop diversification strongly increased in comparison with previous and subsequent periods. In more recent times, the abandonment of agricultural practices has favoured the re-colonisation of mixed woodland or cluster-pine woodland. Conclusion Ancient documents in the ecclesiastic or municipal inventories can be a very useful tool for enhancing the knowledge of agricultural practice, as well as of subsistence methods favoured by local populations during a particular time and for reconstructing land use change over time. PMID:19361339

Gentili, Rodolfo; Gentili, Elio; Sgorbati, Sergio

2009-01-01

133

Winter temperatures in the second half of the XVI century in the central area of the Iberian Peninsula  

NASA Astrophysics Data System (ADS)

This paper studies the winter temperatures of the second part of the XVI century in the central area of the Iberian Peninsula. A large number of historical documents that are stored in many different Spanish archives were consulted in order to carry out this research. The data was first arranged and weighted according to the intensity and significance of the meteorological phenomena described and, subsequently, these values were assigned an ordinal index ranging from +4 to -4. The statistical treatment applied is based on the reconstruction of temperatures equivalent to this ordinal index, expressed as anomalies of the 1961-1990 period, belonging to a reference station located at the approximate geographical center of the area under study. The results show winter thermal conditions different from current ones that, for the most part, stay below the reference average and that occurred with a wide range of variability. The influence that thermal conditions had on the evolution of some environmental aspects are considered based on the forest exploitation problem information and on the wine harvest production.

Bullón, T.

2008-06-01

134

Stability parameters for one-step mechanism of irreversible protein denaturation: a method based on nonlinear regression of calorimetric peaks with nonzero deltaCp.  

PubMed

Thermal transitions of many proteins have been found to be calorimetrically irreversible and scan-rate dependent. Calorimetric determinations of stability parameters of proteins which unfold irreversibly according to a first-order kinetic scheme have been reported. These methods require the approximation that the increase in heat capacity upon denaturation deltaCp is zero. A method to obtain thermodynamic parameters and activation energy for the two-state irreversible process N --> D from nonlinear fitting to calorimetric traces is proposed here. It is based on a molar excess heat capacity function which considers irreversibility and a nonzero constant deltaCp. This function has four parameters: (1) temperature at which the calorimetric profile reaches its maximal value (Tm), (2) calorimetric enthalpy at Tm (deltaHm), (3) deltaCp, and (4) activation energy (E). The thermal irreversible denaturation of subtilisin BPN' from Bacillus amyloliquefaciens was studied by differential scanning calorimetry at pH 7.5 to test our model. Transitions were found to be strongly scanning-rate dependent with a mean deltaCp value of 5.7 kcal K(-1)mol(-1), in agreement with values estimated by accessible surface area and significantly higher than a previously reported value. PMID:15113687

Arroyo-Reyna, Alfonso; Tello-Solís, Salvador R; Rojo-Domínguez, Arturo

2004-05-15

135

Head-group contributions to bilayer stability: monolayer and calorimetric studies on synthetic, stereochemically uniform glucolipids.  

PubMed

Monolayer and differential scanning calorimetry studies have been performed on synthetic, stereochemically uniform glyceroglucolipids having saturated, ether-linked alkyl chains. The limiting area, A0 = 40 A2 X molecule-1, resulting from the monolayer measurements of the glucolipids is comparable to the A0 value found for phosphatidylethanolamine lipids. The area corresponds to twice the value observed with saturated straight chain fatty acids, which indicates that at high surface pressure the space requirement of the glucose head group does not exceed that of the two alkyl chains. The apparent specific heat capacities of the glucolipid dispersions have been found to be higher than those of corresponding phospholipids. They can be approximated from group parameters with the additional assumption that the experimental partial molar heat capacity of glucose is valid for the glucose head groups of the lipids. The transition enthalpies of the C16 and C18 glyceroglucolipids are clearly larger than the delta H values of corresponding phospholipids, while the C14 glyceroglucolipid has the same transition enthalpy as dimyristoylphosphatidylethanolamine or ditetradecylphosphatidylethanolamine. Glucolipids exhibit gel to liquid-crystalline phase transition temperatures which are only slightly lower than those of their phosphatidylethanolamine analogues, although they are uncharged molecules. Like phosphatidylethanolamine the glucolipids do not show a pretransition; however, with the C14 glucolipid a highly cooperative posttransition, approximately 5 deg above the main transition, has been found. Calorimetric experiments with a C14 glucolipid, in which the hydroxyl protons of the glucose moiety have been exchanged by deuterium, suggest that the posttransition might reflect structural changes of the head group.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3994987

Hinz, H J; Six, L; Ruess, K P; Liefländer, M

1985-01-29

136

Absorption of organic compounds and organometallics on ceramic substrates for wear reduction  

SciTech Connect

The concept of employing thermally stable compounds (that is, metal oxides) as high temperature vapor phase ceramic lubricants was investigated. A major part of this study was devoted to the development of various calorimetric and tribological techniques that could be used to determine interfacial reactions between thermally stable compounds and ceramic substrates such as zirconia and alumina. This interaction is pivotal in understanding the mechanism of high temperature lubricity. The approach consisted of selecting low sublimation temperature materials and measuring their thermodynamic interactions as vapors with the ceramic substrates. The materials studied included two easily sublimable organic compounds (that is, naphthalene and salicylic acid) and several organometallics (for example, copper phthalocyanine). Thermodynamic data such as heat of adsorption, packing density, and reversibility of the adsorption were obtained on some of these compounds and were related to wear characteristics. All of these compounds provided effective lubrication at room temperature. Copper phthalocyanine was an effective lubricant at temperatures up to 400 C.

Kennedy, P.J.; Agarwala, V.S. [Naval Air Warfare Center, Patuxent River, MD (United States)

1996-12-31

137

Determination of the activation energy spectrum of structural relaxation in metallic glasses using calorimetric and shear modulus relaxation data  

NASA Astrophysics Data System (ADS)

We consider two methods for reconstruction of the activation energy spectra of structural relaxation from calorimetric and shear modulus relaxation data. The methods are based on the assumption that structural relaxation of metallic glasses can be understood as a relaxation change of the concentration of frozen-in defects similar to dumbbell interstitials (interstitialcies) in simple crystals. For three Pd- and Zr-based glasses taken as an example, it is shown that both methods give nearly the same results. We calculated a decrease of the defect concentration and showed that the heat of structural relaxation per defect for all three glasses practically coincides with the theoretical value of the interstitialcy formation enthalpy.

Tsyplakov, A. N.; Mitrofanov, Yu. P.; Makarov, A. S.; Afonin, G. V.; Khonik, V. A.

2014-09-01

138

Analbite - Sanidine Thermodynamic Mixing Properties: Highly Precise HF Solution Calorimetric Data Across A Twenty-Member Crystalline Solution Series  

NASA Astrophysics Data System (ADS)

Enthalpies of K-Na mixing for the analbite - sanidine feldspar series were investigated by Hovis (1988, J. Petrology) in the early 80's. That work was based on data at a limited number of compositions, owing to the large sample sizes required for HF solution calorimetric measurements at the time. Thermodynamic mixing properties for mineral series, especially those exhibiting compositionally asymmetric mixing quantities, are best defined when samples at a large number of compositions are utilized. Enabled by the small sample sizes now possible for HF solution calorimetric dissolutions (Hovis et al., 1998, Amer. Mineral.), we revisit feldspar thermodynamic properties, having synthesized an analbite - sanidine series consisting of samples at 20 compositions. Solution calorimetric experiments on these samples at 50 °C in 20.1 wt% HF under isoperibolic conditions have resulted in highly precise calorimetric data (standard deviation per sample averaging 0.06 % of the heat of solution). Although enthalpies of K-Na mixing based on the new data display some degree of compositional asymmetry, with a maximum value of 4.8 kJ/mol at a mole fraction potassium of 0.47, the distribution of enthalpy-of-mixing values remains nearly symmetric with respect to K content. This contrasts significantly with data for Al-Si ordered low albite - microcline crystalline solutions, reinvestigated via synthesis of a 21-member series, which show significantly higher mixing magnitudes and considerably greater asymmetry with respect to composition. The maximization of enthalpies of K-Na mixing at sodic compositions correlates well with the sodic critical compositions for both solvi. The lower mixing magnitudes for analbite - sanidine are consistent with the comparatively lower critical temperature of the analbite - sanidine solvus (e.g., Smith & Parsons, 1974, Mineral. Mag.) relative to that for low albite - microcline (Bachinski & Müller, 1971, J. Petrology). Entropies of K-Na mixing for analbite - sanidine have been calculated by combining present enthalpy data with Gibbs free energies of mixing derived from the earlier phase equilibrium study of Hovis et al. (1991, Amer. Mineral.). These may be compared with directly measured entropy data for analbite - sanidine based on the heat capacity measurements of Haselton et al. (1983, Amer. Mineral.). Thanks to the National Science Foundation for funding this research.

Hovis, G. L.

2013-12-01

139

Investigation of ferroelectric phase transitions of water in nanoporous silicates in simultaneous electrical noise and calorimetric measurements  

NASA Astrophysics Data System (ADS)

The phase transitions of water in the nanoporous silicate materials SBA-15 and MCM-41 with an ordered system of cylindrical pores have been investigated. Measurements of low-frequency electrical noises (Barkhausen noises) in the frequency range of 1-100 Hz have been performed simultaneously with relative calorimetric measurements. It has been found that the voltage of electrical fluctuations increases approximately 100 times in the temperature range from -30 to -50°C, which is associated with the first-order and second-order ferroelectric phase transitions. It has been assumed that the ferroelectric ice XI can be formed in capillary pores of the materials under investigations.

Bordonskiy, G. S.; Orlov, A. O.

2014-08-01

140

Confirmation of a calorimetric peculiarity in the crossover region of glass transition in poly( n-hexyl methacrylate) by differential scanning calorimetry  

NASA Astrophysics Data System (ADS)

The Narayanaswamy model for vitrification is modified to deliver local information about the underlying equilibrium trace of calorimetric response in an Arrhenius plot. The analysis of a simple differential scanning calorimetry (DSC) thermogram for polystyrene reproduces the calorimetric equilibrium trace from heat capacity spectroscopy with an accuracy of few tenths of a frequency decade. Further, contour maps for linear dielecric, heat capacity, and shear response in the crossover region of dynamic glass transition in poly( n-hexyl methacrylate) are presented. The calorimetric map has a saddle between the death of the high-temperature process ( a) and the onset of the low-temperature process ( ?). The sigmoid bend in the equilibrium trace near this peculiarity can independently be confirmed by the modified Narayanaswamy model evaluation of a simple DSC thermogram. A speculative, free-volume physical picture of the crossover region is described.

Kahle, S.; Hempel, E.; Beiner, M.; Unger, R.; Schröter, K.; Donth, E.

1999-04-01

141

Measurement of the Fe VIII-Fe XVI 3-3 Emission in the Extreme Ultraviolet and Comparison with CHIANTI  

NASA Astrophysics Data System (ADS)

Laboratory measurements of the n = 3 to n = 3 emission from M-shell iron ions are presented and compared to synthetic spectra from the CHIANTI spectral model. The measurements cover the range 170-290 Å and are made at an electron density of about 1011 cm-3. Emission from Fe VIII through Fe XVI has been identified. Excellent agreement with CHIANTI predictions is found for most lines. Twenty weaker features are noted in the laboratory data that are either absent in CHIANTI or have recently been added and correspond to lines that have not been verified by experimental measurements. A few of these lines may have already been observed (but not yet identified) in the Sun. The features are attributed to emission from various charge states of iron, notably Fe IX and Fe XIII, and two features have been identified as transitions in Fe VIII, i.e., the 3p 63d 2 D 5/2-3p 53d 2 2 P 3/2 and the 3p 63d 2 D 3/2-3p 53d 2 2 P 1/2 transitions at 225.25 ± 0.12 and 226.35 ± 0.10 Å, respectively. Seven lines in Fe XI, Fe XII, and Fe XIII between 200 and 205 Å are noted for which the wavelengths in the CHIANTI database disagree with those in the current database of the National Institute of Standards and Technology. Our measurements of five of these lines appear to agree with the assignments used in CHIANTI.

Beiersdorfer, P.; Lepson, J. K.

2012-08-01

142

Electron impact excitation rates for transitions in beryllium-like P XII, S XIII, Cl XIV, Ar XV and K XVI  

NASA Astrophysics Data System (ADS)

The R-matrix electron excitation rates determined by Berrington et al. (1985) for C III, O V, Ne VII, and Si XI and by Dufton et al. (1983) for Ca XVII are used to interpolate the rates for Be-like P XII, S XIII, Cl XIV, Ar XV, and K XVI. The results are presented in a series of tables and briefly characterized. The accuracy of the present findings is estimated as + or - 10 percent within 0.8 dex of log Tmax, where Tmax is the temperature of maximum fractional abundance for ionization equilibrium. The applicability of the results to the diagnostics of astrophysical and laboratory plasmas is indicated.

Keenan, F. P.

1988-01-01

143

Energetics of the alpha-lactalbumin states: a calorimetric and statistical thermodynamic study.  

PubMed

The temperature dependence of the heat capacity function of holo and apo alpha-lactalbumin has been studied by high sensitivity differential scanning microcalorimetry. The heat capacities of the holo and apo forms in the native state were found to be close to, but somewhat higher than, that of lysozyme, which has a similar structure. At pH values higher than 5, the heat-denatured state and the unfolded state are indistinguishable. At lower pH values, the heat capacity of the state obtained by heat or acid denaturation is lower than what is expected for the completely unfolded polypeptide chain, but it approaches that value at higher temperatures. The heat capacity increment of the denatured state correlates well with the amount of residual structure measured by ellipticity (i.e., the lower the residual structure, the higher the heat capacity). The extent of residual structure in the denatured state, which is exceptionally high in alpha-lactalbumin, decreases upon increasing temperature and at approximately 110 degrees C becomes close to that observed in 6 M GdmCl. Above 110 degrees C, the denatured state of alpha-lactalbumin is practically indistinguishable in heat capacity and ellipticity from the fully unfolded state. The calorimetric data have been analyzed quantitatively using a statistically thermodynamic formalism. This analysis indicates that the long-range or global cooperativity of the protein is lost after heat denaturation of the native state, causing the remaining elements of residual structure to behave in a more or less independent fashion. At pH values close to neutral, heat denaturation occurs at high temperature and yields a totally unfolded polypeptide with no measurable population of partly folded intermediates. At lower pH values, denaturation occurs at lower temperatures and a progressively higher population of intermediates is observed. At pH 4.2, about 50% of the molecules is in compact intermediate states immediately after heat denaturation; however, at pH 3.5, this percentage is close to 80% and at pH 3.0 it reaches about 100% of the protein molecules. Upon heating, the unfolded state progressively becomes the predominant species. The analysis of the heat capacity data for alpha-lactalbumin indicates that the best model to account for the observed behavior is one in which the denatured state is represented as a distribution of substates with varying degrees of residual structure. At low temperatures, the distribution is centered around rather compact substates with significant residual structure. At higher temperatures, the distribution shifts toward states with less residual structure and eventually to the completely unfolded state. PMID:8110793

Griko, Y V; Freire, E; Privalov, P L

1994-02-22

144

Calorimetric AC loss measurement of MgB2 superconducting tape in an alternating transport current and direct magnetic field  

NASA Astrophysics Data System (ADS)

Applications of MgB2 superconductors in electrical engineering have been widely reported, and various studies have been made to define their alternating current (AC) losses. However, studies on the transport losses with an applied transverse DC magnetic field have not been conducted, even though this is one of the favored conditions in applications of practical MgB2 tapes. Methods and techniques used to characterize and measure these losses have so far been grouped into ‘electrical’ and ‘calorimetric’ approaches with external conditions set to resemble the application conditions. In this paper, we present a new approach to mounting the sample and employ the calorimetric method to accurately determine the losses in the concurrent application of AC transport current and DC magnetic fields that are likely to be experienced in practical devices such as generators and motors. This technique provides great simplification compared to the pickup coil and lock-in amplifier methods and is applied to a long length (˜10 cm) superconducting tape. The AC loss data at 20 and 30 K will be presented in an applied transport current of 50 Hz under external DC magnetic fields. The results are found to be higher than the theoretical predictions because of the metallic fraction of the tape that contributes quite significantly to the total losses. The data, however, will allow minimization of losses in practical MgB2 coils and will be used in the verification of numerical coil models.

See, K. W.; Xu, X.; Horvat, J.; Cook, C. D.; Dou, S. X.

2012-11-01

145

Development of Metallic Magnetic Calorimeters for High Precision Measurements of Calorimetric Re-187 and Ho-163 Spectra  

NASA Technical Reports Server (NTRS)

The measurement of calorimetric spectra following atomic weak decays, beta (b) and electron capture (EC), of nuclides having a very low Q-value, can provide an impressively high sensitivity to a non-vanishing neutrino mass. The achievable sensitivity in this kind of experiments is directly connected to the performance of the used detectors. In particular an energy resolution of a few eV and a pulse formation time well below 1 microsecond are required. Low temperature Metallic Magnetic Calorimeters (MMCs) for soft X-rays have already shown an energy resolution of 2.0 eV FWHM and a pulse rise-time of about 90 ns for fully micro-fabricated detectors. We present the use of MMCs for high precision measurements of calorimetric spectra following the beta-decay of Re-187 and the EC of Ho-163. We show results obtained with detectors optimized for Re-187 and for Ho-163 experiments respectively. While the detectors equipped with superconducting Re absorbers have not yet reached the aimed performance, a first detector prototype with a Au absorber having implanted Ho-163 ions already shows excellent results. An energy resolution of 12 eV FWHM and a rise time of 90 ns were measured.

Ranitzsch, P. C.-O.; Porst, J.-P.; Kempf, S.; Pies, C.; Schafer, S.; Hengstler, D.; Fleischmann, A.; Enss, C.; Gastaldo, L.

2012-01-01

146

Dynamic Fuzzy c-Means (dFCM) Clustering and its Application to Calorimetric Data Reconstruction in High Energy Physics  

E-print Network

In high energy physics experiments, calorimetric data reconstruction requires a suitable clustering technique in order to obtain accurate information about the shower characteristics such as position of the shower and energy deposition. Fuzzy clustering techniques have high potential in this regard, as they assign data points to more than one cluster,thereby acting as a tool to distinguish between overlapping clusters. Fuzzy c-means (FCM) is one such clustering technique that can be applied to calorimetric data reconstruction. However, it has a drawback: it cannot easily identify and distinguish clusters that are not uniformly spread. A version of the FCM algorithm called dynamic fuzzy c-means (dFCM) allows clusters to be generated and eliminated as required, with the ability to resolve non-uniformly distributed clusters. Both the FCM and dFCM algorithms have been studied and successfully applied to simulated data of a sampling tungsten-silicon calorimeter. It is seen that the FCM technique works reasonably well, and at the same time, the use of the dFCM technique improves the performance.

Radha Pyari Sandhir; Sanjib Muhuri; Tapan Nayak

2012-04-16

147

Aromatic Compounds  

NSDL National Science Digital Library

These organic chemistry quiz questions from the JCE question bank focus on the topic of aromatic compounds. Included in the quiz are questions on nomenclature, synthesis, electrophilic substitution, and huckel's rule. These questions provide great review and practice material for students.

Reich, Ieva

2007-12-03

148

Population and habitat on the feudal domain iria at the beginning of the XVIth century Eugen Ghita Populaie i habitat pe domeniul cetii iria la nceputul secolului al XVI lea  

E-print Network

Population and habitat on the feudal domain iria at the beginning of the XVIth century Eugen Ghita domeniul cetii iria la începutul secolului al XVI ­lea Eugen Ghi Abstract: The study ,,Population and habitat on the feudal domain iria at the beginning of the XVIth century Eugen Ghita Populaie i habitat pe

Paris-Sud XI, Université de

149

Thermodynamic study of rhodamine 123-calf thymus DNA interaction: determination of calorimetric enthalpy by optical melting study.  

PubMed

In this paper, the interaction of rhodamine123 (R123) with calf thymus DNA has been studied using molecular modeling and other biophysical methods like UV-vis spectroscopy, fluoremetry, optical melting, isothermal titration calorimetry, and circular dichroic studies. Results showed that the binding energy is about -6 to -8 kcal/mol, and the binding process is favored by both negative enthalpy change and positive entropy change. A new method to determine different thermodynamic properties like calorimetric enthalpy and heat capacity change has been introduced in this paper. The obtained data has been crossed-checked by other methods. After dissecting the free-energy contribution, it was observed that the binding was favored by both negative hydrophobic free energy and negative molecular free energy which compensated for the positive free energies due to the conformational change loss of rotational and transitional freedom of the DNA helix. PMID:25383921

Masum, Abdulla Al; Chakraborty, Maharudra; Pandya, Prateek; Halder, Umesh Chandra; Islam, Md Maidul; Mukhopadhyay, Subrata

2014-11-20

150

An assessment by calorimetric calculations of the potential thermal benefit of warming and humidification of insufflated carbon dioxide.  

PubMed

Heat transfer from a patient to warm and humidify insufflated carbon dioxide (CO2) during laparoscopic surgery may contribute to perioperative hypothermia. The magnitude of this effect was calculated using calorimetric calculations. Warming to 37°C and humidifying to 100%, each 100?L of insufflated CO2 would prevent a heat transfer of 3220 calories, which would result in a decrease of temperature by 0.06°C in a 70 kg patient after total body distribution of heat. We conclude that the thermal benefit of warming and humidifying insufflated CO2 is minor, particularly in comparison with other effective and inexpensive perioperative technologies, some of which are not always used out could easily be used. The decision to use heating and humidification of insufflated CO2 should be based on its other risks, benefits, and costs. PMID:24710263

Roth, Jonathan V; Sea, Stephanie

2014-06-01

151

Application of Calorimetric Low Temperature Detectors (CLTD's) for Precise Stopping Power Measurements of Heavy Ions in Matter  

NASA Astrophysics Data System (ADS)

Calorimetric low temperature detectors (CLTD's) have been included in a B-ToF setup, that has already been used several times to perform energy loss measurements at the accelerator laboratory of the University of Jyväskylä. The new experimental setup enabled a precise determination of stopping power data for 0.05-1 MeV/u Xe ions in carbon, nickel and gold. The results are presented and compared to data from literature and theoretical predictions. As a by-product, due to the excellent energy resolution of CLTD's for heavy ions at low energies, an observation of channeling effects in very thin polycrystalline targets and a determination of the channeling energy loss for 0.1-0.5 MeV/u Xe-ions in Ni- and Au-absorbers was possible.

Echler, A.; Egelhof, P.; Grabitz, P.; Kettunen, H.; Kraft-Bermuth, S.; Laitinen, M.; Müller, K.; Rossi, M.; Trzaska, W. H.; Virtanen, A.

2014-09-01

152

Effect of Composition Heterogeneity on the Calorimetric Glass Transition in Polymer/Solvent and Solvent/Solvent Mixtures  

NASA Astrophysics Data System (ADS)

The composition dependence of the calorimetric Tg has been reported for several polymer blend systems, but there are relatively few studies of mixtures of small molecule glass formers over the entire composition range. The use of small molecule glasses eliminates the constraint of chain connectivity in describing the Tg for one or both of the components. We report the measurement of Tg for mixtures of small-molecule glass formers, and of polystyrene (PS) solutions with a series of dialkyl phthalates (DAPs) as a function of composition. Mixtures of o-terphenyl with tri-m-tolylphosphate exhibit a nearly linear relationship between Tg and volume fraction, with no appreciable broadening of the DSC trace in the transition region. In contrast, PS/DAP mixtures show strong deviations from Flory-Fox behavior for low concentrations of PS. These results are discussed in terms of current models of composition heterogeneity.

Lodge, Timothy P.; Savin, Daniel A.; Larson, Anne M.

2003-03-01

153

Calorimetric analysis of the two way memory effect in a NiTi alloy -- Experiments and calculations  

SciTech Connect

In addition to the well known one-way memory effect in heating, some shape memory alloys may also exhibit a shape recovery upon cooling, i.e. they show the two-way memory effect (TWME). This is not an inherent property of such alloys, and to obtain it, the alloy must be trained. Besides the two-way memory effect, the training processes can also cause changes such as a shift of the transformation temperatures. In this work a calorimetric investigation of a one-way and two-way NiTi memory alloy is presented. The heat flow was measured by use of a Differential Scanning Calorimeter. The differences in the temperatures and enthalpy of transformations between one-way and two-way memory samples are presented, compared and discussed. A mathematical prediction of the heat and temperatures of transformation is presented.

Silva, E.P. da [Technical Univ. of Berlin (Germany). Inst. of Thermodynamics] [Technical Univ. of Berlin (Germany). Inst. of Thermodynamics

1999-04-23

154

A more unified picture for the thermodynamics of nucleic acid duplex melting: A characterization by calorimetric and volumetric techniques  

PubMed Central

We use a combination of calorimetric and volumetric techniques to detect and to characterize the thermodynamic changes that accompany helix-to-coil transitions for five polymeric nucleic acid duplexes. Our calorimetric measurements reveal that melting of the duplexes is accompanied by positive changes in heat capacity (?CP) of similar magnitude, with an average ?CP value of 64.6 ± 21.4 cal deg?1 mol?1. When this heat capacity value is used to compare significantly different transition enthalpies (?Ho) at a common reference temperature, Tref, we find ?HTref for duplex melting to be far less dependent on duplex type, base composition, or base sequence than previously believed on the basis of the conventional assumption of a near-zero value for ?CP. Similarly, our densimetric and acoustic measurements reveal that, at a given temperature, all the AT- and AU-containing duplexes studied here melt with nearly the same volume and compressibility changes. In the aggregate, our results, in conjunction with literature data, suggest a more unified picture for the thermodynamics of nucleic acid duplex melting. Specifically, when compared at a common temperature, the apparent large differences present in the literature for the transition enthalpies of different duplexes become much more compressed, and the melting of all-AT- and all-AU-containing duplexes exhibits similar volume and compressibility changes despite differences in sequence and conformation. Thus, insofar as thermodynamic properties are concerned, when comparing duplexes, the temperature under consideration is as important as, if not more important than, the duplex type, the base composition, or the base sequence. This general behavior has significant implications for our basic understanding of the forces that stabilize nucleic acid duplexes. This behavior also is of practical significance in connection with the use of thermodynamic databases for designing probes and for assessing the affinity and specificity associated with hybridization-based protocols used in a wide range of sequencing, diagnostic, and therapeutic applications. PMID:10393911

Chalikian, Tigran V.; Volker, Jens; Plum, G. Eric; Breslauer, Kenneth J.

1999-01-01

155

Intermetallic Compounds  

NASA Astrophysics Data System (ADS)

We have focused on the binary narrow-bandgap intermetallic compounds FeGa3 and RuGa3 as thermoelectric materials. Their crystal structure is FeGa3-type (tetragonal, P42/ mnm) with 16 atoms per unit cell. Despite their simple crystal structure, their room temperature thermal conductivity is in the range 4-5-W-m-1-K-1. Both compounds have narrow-bandgaps of approximately 0.3-eV near the Fermi level. Because their Seebeck coefficients are quite large negative values in the range 350-<-| S 373K|-<-550- ?V-K-1 for undoped samples, it should be possible to obtain highly efficient thermoelectric materials both by adjusting the carrier concentration and by reducing the thermal conductivity. Here, we report the effects of doping on the thermoelectric properties of FeGa3 and RuGa3 as n and p-type materials. The dimensionless figure of merit, ZT, was significantly improved by substitution of Sn for Ga in FeGa3 (electron-doping) and by substitution of Zn for Ga in RuGa3 (hole-doping), mainly as a result of optimization of the electronic part, S 2 ?.

Takagiwa, Y.; Matsuura, Y.; Kimura, K.

2014-06-01

156

Design of a Precision Calorimetric System for Measuring Heats of Solution  

Microsoft Academic Search

A submarine-type solution calorimeter has been built. The calorimeter can be used to measure the heats of solution of solid and gaseous compounds. The standard heats of solution of KC1 and LiC1 in water and heat of reaction of THAM with 0.1 N HC1 agree well (within 0.2%) with the literature values.

OM N. Bhatnagar; A. N. Campbell

1972-01-01

157

Thermochemistry of Bithiophenes and Thienyl Radicals. A Calorimetric and Computational Study  

NASA Astrophysics Data System (ADS)

The relative stabilities of 2,2'- and 3,3'-bithiophenes were evaluated by experimental thermochemistry and the results compared with data obtained from state of the art calculations, which were also extended to 2,3'-bithiophene. The standard (p° = 0.1 MPa) molar enthalpies of formation of crystalline 2,2'-bithiophene and 3,3'-bithiophene were calculated from the standard molar energies of combustion, in oxygen, to yield CO2 (g) and H2SO4·115H2O, measured by rotating-bomb combustion calorimetry at T = 298.15 K. The vapor pressures of these two compounds were measured as a function of temperature by Knudsen effusion mass-loss technique. The standard molar enthalpies of sublimation, at T = 298.15 K, were derived from the Clausius-Clapeyron equation. The experimental values were used to calculate the standard (p° = 0.1 MPa) enthalpies of formation of the title compounds in the gaseous phase; the results were analyzed and interpreted in terms of enthalpic increments and molecular structure. Standard ab initio molecular orbital calculations at the G3(MP2)//B3LYP level were performed. Enthalpies of formation, using homodesmotic reactions, were calculated and compared with experimental data. The computational study was also extended to the isomeric compound 2,3'-bithiophene. Detailed inspections of the molecular and electronic structures of the compounds studied were carried out. Finally, bond dissociation enthalpies (BDE) and enthalpies of formation of thienyl radicals were also computed.

Ribeiro da Silva, Manuel A. V.; Santos, Ana Filipa L. O. M.; Gomes, José R. B.; Roux, María Victoria; Temprado, Manuel; Jiménez, Pilar; Notario, Rafael

2009-09-01

158

Bismaleimide compounds  

DOEpatents

Bismaleimides of the formula shown in the diagram wherein R[sub 1] and R[sub 2] each independently is H, C[sub 1-4]-alkyl, C[sub 1-4]-alkoxy, Cl or Br, or R[sub 1] and R[sub 2] together form a fused 6-membered hydrocarbon aromatic ring, with the proviso that R[sub 1] and R[sub 2] are not t-butyl or t-butoxy; X is O, S or Se; n is 1--3; and the alkylene bridging group, optionally, is substituted by 1--3 methyl groups or by fluorine, form polybismaleimide resins which have valuable physical properties. Uniquely, these compounds permit extended cure times, i.e., they remain fluid for a time sufficient to permit the formation of a homogeneous melt prior to curing.

Adams, J.E.; Jamieson, D.R.

1986-01-14

159

Bismaleimide compounds  

DOEpatents

Bismaleimides of the formula ##STR1## wherein R.sub.1 and R.sub.2 each independently is H, C.sub.1-4 -alkyl, C.sub.1-4 -alkoxy, C1 or Br, or R.sub.1 and R.sub.2 together form a fused 6-membered hydrocarbon aromatic ring, with the proviso that R.sub.1 and R.sub.2 are not t-butyl or t-butoxy; X is O, S or Se; n is 1-3; and the alkylene bridging group, optionally, is substituted by 1-3 methyl groups or by fluorine, form polybismaleimide resins which have valuable physical properties. Uniquely, these compounds permit extended cure times, i.e., they remain fluid for a time sufficient to permit the formation of a homogeneous melt prior to curing.

Adams, Johnnie E. (Grandview, MO); Jamieson, Donald R. (Merriam, KS)

1986-01-14

160

Synthesis of functionalized tetrazenes as energetic compounds.  

PubMed

1,4-Bis[1-(2-hydroxyethyl)-1H-tetrazol-5-yl]-1,4-dimethyl-2-tetrazene (12a), 1,4-bis[1-isopropoxycarbonylmethyl-1H-tetrazol-5-yl]-1,4-dimethyl-2-tetrazene (12b), and 1,4-bis[1-carboxymethyl-1H-tetrazol-5-yl]-1,4-dimethyl-2-tetrazene (13) have been synthesized as new nitrogen-rich compounds. The tetrazenes were obtained by oxidation of the corresponding tetrazolylhydrazines using bromine. Moreover, a new method to prepare tetrazolylhydrazines in high yield using 5-bromotetrazoles has been developed. 12a, 12b, and 13 were characterized using vibrational spectroscopy (IR, Raman), mass spectrometry, and multinuclear NMR spectroscopy. The crystal structures of 12a, 12b, and 13 were determined using single crystal X-ray diffraction. Furthermore, the energetic properties of 12a, 12b, and 13 have been investigated using DSC and bomb calorimetric measurements. The sensitivity data toward impact and friction has been determined using BAM methods. PMID:19222166

Heppekausen, Johannes; Klapötke, Thomas M; Sproll, Stefan M

2009-03-20

161

Detection of nitrite and nitrosocompounds in chemical systems and biological liquids by the calorimetric method  

Microsoft Academic Search

The capacity of nitrite, S-nitrosothiols (RS-NO), dinitrosyl iron complexes (DNICs) with thiolcontaining ligands, and nitrosoamines\\u000a to inhibit catalase has been used for the selective determination of these compounds in purely chemical systems and biological\\u000a liquids: cow milk and colostrum. The limiting sensitivity of the method is 50 nM. A comparison of the results of the determinations\\u000a of RS-NO, DNIC, and

V. Yu. Titov; Yu. M. Petrenko; A. F. Vanin; I. I. Stepuro

2010-01-01

162

New methodology for simultaneous volumetric and calorimetric measurements: Direct determination of {alpha}{sub p} and C{sub p} for liquids under pressure  

SciTech Connect

A new batch cell has been developed to measure simultaneously both isobaric thermal expansion and isobaric heat capacity from calorimetric measurements. The isobaric thermal expansion is directly proportional to the linear displacement of an inner flexible below and the heat capacity is calculated from the calorimetric signal. The apparatus used was a commercial Setaram C-80 calorimeter and together with this type of vessels can be operated up to 20 MPa and in the temperature range of 303.15-523.15 K, In this work, calibration was carried out using 1-hexanol and subsequently both thermophysical properties were determined for 3-pentanol, 3-ethyl-3-pentanol, and 1-octanol at atmospheric pressure, 5 and 10 MPa, and from 303.15 to 423.15 K in temperature. Finally experimental values were compared with the literature in order to validate this new methodology, which allows a very accurate determination of isobaric thermal expansion and isobaric heat capacity.

Casas, L. M. [Departamento de Fisica Aplicada, Facultad de Ciencias Experimentales, Universidad de Vigo, Lagoas Marcosende s/n, 36310 Vigo (Spain); Plantier, F.; Bessieres, D. [Laboratoire de Thermodynamique et Energetique des Fluides Complexes-UMR 5150, Universite de Pau et des Pays de l'Adour, BP 1155, 64013 Pau (France)

2009-12-15

163

Calorimetric and computational study of thiacyclohexane 1-oxide and thiacyclohexane 1,1-dioxide (thiane sulfoxide and thiane sulfone). Enthalpies of formation and the energy of the S=O bond.  

PubMed

A rotating-bomb combustion calorimeter specifically designed for the study of sulfur-containing compounds [J. Chem. Thermodyn. 1999, 31, 635] has been used for the determination of the enthalpy of formation of thiane sulfone, 4, Delta(f)H(o) m(g) = -394.8 +/- 1.5 kJ x mol(-1). This value stands in stark contrast with the enthalpy of formation reported for thiane itself, Delta(f)H(o) m(g) = -63.5 +/- 1.0 kJ x mol(-1), and gives evidence of the increased electronegativity of the sulfur atom in the sulfonyl group, which leads to significantly stronger C-SO2 bonds. Given the known enthalpy of formation of atomic oxygen in the gas phase, Delta(f)H(o) m(O,g) = +249.18 kJ x mol(-1), and the reported bond dissociation energy for the S=O bond in alkyl sulfones, BDE(S=O) = +470.0 kJ x mol(-1), it was possible to estimate the enthalpy of formation of thiane sulfoxide, 5, a hygroscopic compound not easy to use in experimental calorimetric measurements, Delta(f)H(o) m(5) = -174.0 kJ x mol(-1). The experimental enthalpy of formation of both 4 and 5 were closely reproduced by theoretical calculations at the G2(MP2)+ level, Delta(f)H(o) m(4) = -395.0 kJ x mol(-1) and Delta(f)H(o) m(5) = -178.0 kJ x mol(-1). Finally, calculated G2(MP2)+ values for the bond dissociation energy of the S=O bond in cyclic sulfoxide 5 and sulfone 4 are +363.7 and +466.2 kJ x mol(-1), respectively. PMID:12608789

Roux, María Victoria; Temprado, Manuel; Jiménez, Pilar; Dávalos, Juan Zenón; Notario, Rafael; Guzmán-Mejía, Ramón; Juaristi, Eusebio

2003-03-01

164

Thermotropic phase behavior of model membranes composed of phosphatidylcholines containing cis-monounsaturated acyl chain homologues of oleic acid: differential scanning calorimetric and /sup 31/P NMR spectroscopic studies  

SciTech Connect

The thermotropic phase behavior of dioleoylphosphatidylcholine and six of its longer chain homologues was studied by differential scanning calorimetry and /sup 31/P nuclear magnetic resonance (NMR) spectroscopy. Aqueous dispersions of these compounds all exhibit a single endotherm upon heating but upon cooling exhibit at least two exotherms, both of which occur at temperatures lower than those of their heating endotherm. The single transition observed upon heating was shown by /sup 31/P NMR spectroscopy to be a net conversion from a condensed, subgel-like phase (L/sub c/ phase) to the liquid-crystalline state. Aqueous ethylene glycol dispersions of these compounds also exhibit single endotherms upon heating and cooling exotherms centered at temperatures lower than those of their corresponding heating endotherm. However, the behavior of the aqueous ethylene glycol dispersions differs with respect to their transition temperatures and enthalpies as well as the extent of undercooling observed, and there is some evidence of discontinuities in the cooling behavior of the odd- and even-numbered members of the homologous series. Like the aqueous dispersions, /sup 31/P NMR spectroscopy also shows that the calorimetric events observed in aqueous ethylene glycol involve net interconversions between an L/sub c/-like phase and the liquid-crystalline state. These results demonstrate that although the presence of a cis double bond can perturb the solid-state packing of the acyl chains, its presence does not preclude the formation of highly ordered subgel-like phases in lipid bilayers. In the particular case of these unsaturated phosphatidylcholines, the formation of the subgel phases is more kinetically favorable than is the case with their saturated n-acyl counterparts.

Lewis, R.N.A.H.; Sykes, B.D.; McElhaney, R.N.

1988-02-09

165

A Calorimetric Study of Almandine: Are the Thermodynamic Properties of the End-Member Aluminosilicate Garnets Finally Known Quantitatively?  

NASA Astrophysics Data System (ADS)

The aluminosilicate garnets (E3Al2Si3O12 with E = Fe2+, Mn2+, Ca, Mg) form an important rock-forming mineral group. Much study has been directed toward determining their thermodynamic properties. The iron end-member almandine (Fe3Al2Si3O12) is a key phase in many petrologic investigations. As part of an ongoing calorimetric and thermodynamic study of the aluminosilicate garnets, the heat capacity of three synthetic well-characterized polycrystalline almandine garnets and one natural almandine-rich single crystal was measured. The various garnets were characterized by optical microscopy, electron-microprobe analysis, X-ray powder diffraction and 57Fe Mössbauer spectroscopy. Heat capacity measurements were performed in the temperature range 3 to 300 K using relaxation calorimetry and between 282 and 764 K using DSC methods. From the former, So values between 336.7 ± 0.8 and 337.8 ± 0.8 J/molK are calculated for the different samples. The smaller value is considered the best So for end-member stoichiometric almandine, because it derives from the "best" Fe3+-free synthetic sample. The Cp behavior for almandine at T > 298 K is given by the polynomial (in J/molK): Cp = 649.06(±4) - 3837.57(±122)T-0.5 - 1.44682(±0.06)107T-2 + 1.94834(±0.09)109T-3, which is calculated using DSC data together with one published heat-content datum determined by transposed-drop calorimetry along with a new determination that gives H1181K - H302K = 415.0 ± 3.2 kJ/mole. Almandine shows a ?-type heat-capacity anomaly at low temperatures resulting from a paramagnetic-antiferromagnetic phase transition at about 9 K. The lattice heat capacity was calculated using the single-parameter phonon dispersion model of Komada and Westrum (1997), which allows the non-lattice heat capacity (Cex) behavior to be modelled. An analysis shows the presence of an electronic heat-capacity contribution (Cel - Schottky anomaly) around 17 K that is superimposed on a larger magnetic heat-capacity effect (Cmag). The calculated lattice entropy at 298.15 K is Svib = 303.3 J/molK and it contributes about 90% to the total standard entropy at 298 K. The non-lattice entropy is Sex = 33.4 J/molK and consists of Smag = 32.1 J/molK and Sel = 1.3 J/molK contributions. Using the So = 336.7 J/molK value and the Cp polynomial for almandine, we derived its enthalpy of formation, ?Hof, from an analysis of experimental phase equilibrium results on the reactions almandine + 3rutile = 3ilmenite + sillimanite + 2quartz and 2ilmenite = 2iron + 2rutile + O2. ?Hof = -5269.63 kJ/mol was obtained. So for grossular, pyrope, spessartine, and almandine, as well as their Cp behavior to high temperatures, have all been measured calorimetrically. Uncertainties in older calorimetric studies appear to have been resolved. The standard thermodynamic properties Vo and So are now well determined for all four garnets. In addition, ?Hof for all, except possibly spessartine, also appear to be well known.

Dachs, E.; Geiger, C. A.; Benisek, A.

2012-12-01

166

Calorimetric evaluation of the effects of SiC concentration on precipitation processes in SiC particulate-reinforced 7091 aluminium  

Microsoft Academic Search

A comprehensive differential scanning calorimetric (DSC) investigation has been conducted on the precipitation and dissolution behaviour of SiC particulate-reinforced 7091 aluminium. DSC is shown to be a particularly attractive experimental technique for developing new thermal and thermomechanical processes for aluminium-based metal matrix composites. These new processes are necessitated due to the deleterious effects that the SiC reinforcement causes on the

J. L. Petty-Galis; R. D. Goolsby

1989-01-01

167

Calorimetric and densimetric examinations of aqueous solutions of heptylene1,7- bis (dimethyloctylammonium bromide) and octylene-1,8- bis (dimethyloctylammonium bromide)  

Microsoft Academic Search

The critical micelle concentrations of gemini surfactants having different spacer chain lengths 8-7-8 and 8-8-8 in aqueous\\u000a solutions have been determined by calorimetric and densimetric methods within a wide temperature range. The isothermal volume\\u000a change upon micellisation of the title surfactants has been obtained from density measurements using pseudo-phase model. Predicted\\u000a values for apparent molar volume of the surfactant at

Henryk PiekarskiKatarzyna; Katarzyna ?udzik; Micha? Wasiak

2011-01-01

168

Thermochemistry of 2- and 3-thiopheneacetic acids: calorimetric and computational study.  

PubMed

The enthalpies of formation in the condensed and gas states, Delta f H m degrees (cd) and Delta f H m degrees (g), of 2- and 3-thiopheneacetic acids were derived from their respective enthalpies of combustion in oxygen, measured by a rotating bomb calorimeter, and the variation of vapor pressure with temperature determined by the Knudsen effusion technique. Theoretical calculations at the G3 level were performed, and a study on molecular and electronic structure of the compounds has been carried out. Calculated Delta f H m degrees (g) values using atomization and isodesmic reactions are compared with the experimental data. Experimental and theoretical results show that the 3-thiopheneacetic acid is thermodynamically more stable than the 2-isomer. PMID:18816026

Temprado, Manuel; Roux, María Victoria; Jiménez, Pilar; Foces-Foces, Concepción; Notario, Rafael

2008-10-16

169

Calorimetric vs. van't Hoff binding enthalpies from isothermal titration calorimetry: Ba2+-crown ether complexation.  

PubMed

The 1:1 complexation reaction between Ba(2+) and 18-crown-6 ether is re-examined using isothermal titration calorimetry (ITC), with the goal of clarifying previously reported discrepancies between reaction enthalpies estimated directly (calorimetric) and indirectly, from the temperature dependence of the reaction equilibrium constant K (van't Hoff). The ITC thermograms are analyzed using three different non-linear fit models based on different assumptions about the data error: constant, proportional to the heat and proportional but correlated. The statistics of the fitting indicate a preference for the proportional error model, in agreement with expectations for the conditions of the experiment, where uncertainties in the delivered titrant volume should dominate. With attention to proper procedures for propagating statistical error in the van't Hoff analysis, the differences between Delta H(cal) and Delta H(vH) are deemed statistically significant. In addition, statistically significant differences are observed for the Delta H(cal) estimates obtained for two different sources of Ba(2+), BaCl(2) and Ba(NO(3))(2). The effects are tentatively attributed to deficiencies in the standard procedure in ITC of subtracting a blank obtained for pure titrant from the thermogram obtained for the sample. PMID:15223140

Mizoue, Laura S; Tellinghuisen, Joel

2004-07-01

170

Structural, calorimetric and magnetic properties study of the Cu0,91Fe0,09O system  

NASA Astrophysics Data System (ADS)

In this work the Cu0.91Fe0.09O nanocrystalline system was prepared via the co-precipitation method. Using Mössbauer Spectrometry, X-Ray Diffraction, Vibrating Sample Magnetometry, Thermogravimetry and Differential Scanning Calorimetry, we study the magnetic behavior, and the structural and calorimetric properties of this system. X-ray diffraction shows only the presence of the CuO structural monoclinic phase, suggesting that Cu atoms are substituted by Fe ones. This hypothesis was confirmed by Mössbauer spectrometry at room temperature, because it shows that the spectrum is formed by two doublets, which correspond to Fe + 2 and Fe + 3 sites. Hysteresis cycles obtained by vibrating sample magnetometry detect a soft ferromagnetic behavior at room temperature with coercive fields between 8 and 20 Oe. At T = 20 K the sample shows a hard-magnetic behavior. The thermogravimetry results show a Néel temperature (T N > 440 °C). The differential scanning calorimetry curve show two endothermic peaks in the 90-120 °C range.

Colorado, H. D.; Hernandez, J. S. Trujillo; Alcázar, G. A. Pérez; Bolaños, Alberto

2013-04-01

171

Structural, calorimetric and magnetic properties study of the Cu0,91Fe0,09O system  

NASA Astrophysics Data System (ADS)

In this work the Cu0.91Fe0.09O nanocrystalline system was prepared via the co-precipitation method. Using Mössbauer Spectrometry, X-Ray Diffraction, Vibrating Sample Magnetometry, Thermogravimetry and Differential Scanning Calorimetry, we study the magnetic behavior, and the structural and calorimetric properties of this system. X-ray diffraction shows only the presence of the CuO structural monoclinic phase, suggesting that Cu atoms are substituted by Fe ones. This hypothesis was confirmed by Mössbauer spectrometry at room temperature, because it shows that the spectrum is formed by two doublets, which correspond to Fe + 2 and Fe + 3 sites. Hysteresis cycles obtained by vibrating sample magnetometry detect a soft ferromagnetic behavior at room temperature with coercive fields between 8 and 20 Oe. At T = 20 K the sample shows a hard-magnetic behavior. The thermogravimetry results show a Néel temperature (T N > 440 °C). The differential scanning calorimetry curve show two endothermic peaks in the 90-120 °C range.

Colorado, H. D.; Hernandez, J. S. Trujillo; Alcázar, G. A. Pérez; Bolaños, Alberto

2014-01-01

172

A calorimetric characterization of Cr(VI)-reducing Arthrobacter oxydans at different phases of the cell growth cycle.  

PubMed

This is the first of a series of calorimetric studies designed to characterize and understand survival mechanisms of metal-reducing bacteria isolated from metal-polluted environments. In this paper we introduce a new concept of thermal spectrum of the endothermic melting of complex biological systems (e.g., proteins, nucleic acids, ribosomes, membrane structures) in intact cells. All thermal spectra measured are thermograms that describe the temperature dependence of heat capacity change of the complex systems of biologically active substances in bacterial cells. This new concept of thermal spectrum was applied to investigate spectral features from intact cells of Cr(VI)-reducer Arthrobacter oxydans at different points of their growth conditions and stages. Over the temperature range of 40-105 degrees C, we observed that spectral changes are particularly significant in the 40-90 degrees C interval. This may correspond to the orderly changes in subcellular structural elements: proteins, ribosomes and RNA, membranes, and various structural elements of the cell wall during different points of the growth cycle and growth conditions. Spectral changes in the 90-105 degrees C region are less pronounced, implicating that the structural composition of DNA-Protein (DNP) complexes may change little. PMID:12806104

Bakradze, Nugzar G; Abuladze, Marina K; Sokhadze, Victor M; Asatiani, Nina V; Sapojnikova, Nelly A; Kartvelishvili, Tamara M; Namchevadze, Emma N; Tsibakhashvili, Nelly Y; Tabatadze, Leila V; Lejava, Lia V; Holman, Hoi-Ying

2003-05-28

173

Photophysical and calorimetric investigation on the structural reorganization of poly(A) by phenothiazinium dyes azure A and azure B.  

PubMed

Poly(A) has significant relevance to mRNA stability, protein synthesis and cancer biology. The ability of two phenothiazinium dyes azure A (AA) and azure B (AB) to bind single-stranded poly(A) was studied by spectroscopic and calorimetric techniques. Strong binding of the dyes and the higher affinity of AA over AB were ascertained from absorbance and fluorescence experiments. Significant perturbation of the circular dichroism spectrum of poly(A) in the presence of these molecules with formation of induced CD bands in the 300-700 nm region was observed. Strong emission polarization of the bound dyes and strong energy transfer from the adenine base pairs of poly(A) suggested intercalative binding to poly(A). Intercalative binding was confirmed from fluorescence quenching experiments and was predominantly entropy driven as evidenced from isothermal titration calorimetry data. The negative values of heat capacity indicated involvement of hydrophobic forces and enthalpy-entropy compensation suggested noncovalent interactions in the complexation for both the dyes. Poly(A) formed a self-assembled structure on the binding of both the dyes that was more favored under higher salt conditions. New insights in terms of spectroscopic and thermodynamic aspects into the self-structure formation of poly(A) by two new phenothiazinium dyes that may lead to structural and functional damage of mRNA are revealed from these studies. PMID:24953877

Paul, Puja; Kumar, Gopinatha Suresh

2014-08-01

174

Elastic and Irreversible Energies of a Two-Stage Martensitic Transformation in NiTi Utilizing Calorimetric Measurements  

NASA Astrophysics Data System (ADS)

Elastic energy and irreversible energy are quantified based on calorimetric measurements. We analyze energetics for each stage of the stress-free, thermally induced two-stage phase transformation A ? R ? B19' in an aged Ni-rich NiTi shape memory alloy. Heating/cooling rates are imposed from 1 K/min up to 100 K/min. We compare energetic analysis after multiple thermal cycles to virgin ( i.e., first-cycle) material. Fundamental thermodynamic formulations are applied from two perspectives: the free energy change d G, and the rate of change of free energy expressed as d G/d f m. Two measures of irreversible contributions are defined: the difference between the forward and reverse transformation heats, and the product of the entropy and the thermal hysteresis. Higher values are determined for the former. For scan rates of 10 K/min and greater, the energetic values become relatively stable. Substantial variations are evident at 1, 5, and 10 K/min. The scan rate impacts the elastic strain energy and irreversible energy of the B19' markedly compared with the R-phase transition. The findings are rationalized considering morphologic changes at the lower scan rates and the impacts on elastic and irreversible energies.

Lanba, Asheesh; Hamilton, Reginald F.

2014-06-01

175

Calorimetric and computational study of 1,3- and 1,4-oxathiane sulfones.  

PubMed

The enthalpies of formation in the condensed and gas states, DeltafH degrees m(cd) and DeltafH degrees m(g), of 1,3- and 1,4-oxathiane sulfones were derived from their respective enthalpies of combustion in oxygen, measured by a rotating bomb calorimeter and the variation of vapor pressures with temperatures determined by the Knudsen effusion technique. Standard ab initio molecular orbital calculations at the G2(MP2) and G3 levels were performed, and a theoretical study on molecular and electronic structure of the compounds has been carried out. Calculated DeltafH degrees m(g) values at the G3 level using atomization reactions agree well with the experimental ones. These experimental and theoretical studies support that the destabilization found in 1,3-oxathiane sulfone, 11.2 kJ mol-1 respecting to 1,4-oxathiane sulfone, is due to the electrostatic repulsion between the negative charges of the axial oxygen of the sulfone and the oxygen of the ring and apparently masks any stabilization originating from the hyperconjugative nO --> sigma*C-SO2 stereoelectronic interaction. PMID:17288369

Roux, María Victoria; Temprado, Manuel; Jiménez, Pilar; Notario, Rafael; Guzman-Mejía, Ramón; Juaristi, Eusebio

2007-02-16

176

Energy levels, radiative rates and electron impact excitation rates for transitions in Be-like Cl XIV, K XVI and Ge XXIX  

E-print Network

Results for energy levels, radiative rates and electron impact excitation (effective) collision strengths for transitions in Be-like Cl XIV, K XVI and Ge XXIX are reported. For the calculations of energy levels and radiative rates the General-purpose Relativistic Atomic Structure Package ({\\sc grasp}) is adopted, while for determining the collision strengths and subsequently the excitation rates, the Dirac Atomic R-matrix Code ({\\sc darc}) is used. Oscillator strengths, radiative rates and line strengths are listed for all E1, E2, M1 and M2 transitions among the lowest 98 levels of the $n \\le$ 4 configurations. Furthermore, lifetimes are provided for all levels and comparisons made with available theoretical and experimental results. Resonances in the collision strengths are resolved in a fine energy mesh and averaged over a Maxwellian velocity distribution to obtain the effective collision strengths. Results obtained are listed over a wide temperature range up to 10$^{7.8}$ K, depending on the ion.

Aggarwal, K M

2014-01-01

177

Compounding in Ukraine.  

PubMed

Pharmaceutical compounding in modern Ukraine has a rich history and goes back to ancient times. Today in the Ukraine, there is a revival of compounding practice, the opening of private compounding pharmacies, updating of legislative framework and requirements of the State Pharmacopeia of Ukraine for compounding preparations, and the introduction of Good Pharmaceutical Practice. PMID:23696172

Zdoryk, Oleksandr A; Georgiyants, Victoriya A; Gryzodub, Oleksandr I; Schnatz, Rick

2013-01-01

178

Sanskrit Compound Processor  

NASA Astrophysics Data System (ADS)

Sanskrit is very rich in compound formation. Typically a compound does not code the relation between its components explicitly. To understand the meaning of a compound, it is necessary to identify its components, discover the relations between them and finally generate a paraphrase of the compound. In this paper, we discuss the automatic segmentation and type identification of a compound using simple statistics that results from the manually annotated data.

Kumar, Anil; Mittal, Vipul; Kulkarni, Amba

179

Relativistic Fine Structure Transition Probabilities for Li-LIKE Ions: C IV - si XII, S XIV, ar XVI, ca XVIII, ti XX, cr XXII, and ni XXVI  

NASA Astrophysics Data System (ADS)

Ab initio relativistic calculations employing the Breit-Pauli R-matrix (BPRM) method are reported for fine structure energy levels and oscillator strengths upto n = 10 and 0 <= l <= 9 for 15 Li-like ions: C IV, N V, O VI, F VII, Ne VIII, Na IX, Mg X, Al XI, Si XII, S XIV, Ar XVI, Ca XIII, Ti XX, Cr XXII, and Ni XXVI. About one hundred bound fine structure energy levels of total angular momenta, 1/2 <= J <= 17/2 of even and odd parities, total orbital angular momenta, 0 <= L <= 9 and spin multiplicity (2S+1) = 2, 4 are considered for each ion. The levels provide almost 900 dipole allowed and intercombination transitions. The BPRM method enables consideration of many sets of transition arrays with uniform accuracy comparable to other ab inito theoretical methods, but which entail a much smaller number of transitions. The close coupling eigenfunction expansion for each ion includes the lowest 17 fine structure energy levels of the He-like core configurations 1s^2, 1s2s, 1s2p, 1s3s, 1s3p, and 1s3d. The calculated level energies agree with the measured values to within 1% for most levels. The transition probabilities show good agreement with the best available values. The results provide the largest sets of energy levels and transition rates for these ions, and are expected to be useful in the analysis of X-ray and EUV astrophysical sources. Partial support from the NSF and NASA is acknowledged.

Nahar, Sultana

2002-05-01

180

Relativistic fine structure oscillator strengths for Li-like ions: C IV - Si XII, S XIV, Ar XVI, Ca XVIII, Ti XX, Cr XXII, and Ni XXVI  

NASA Astrophysics Data System (ADS)

Ab initio calculations including relativistic effects in the Breit-Pauli R-matrix (BPRM) method are reported for fine structure energy levels and oscillator strengths upto n = 10 and 0 <= l <= 9 for 15 Li-like ions: C IV, N V, O VI, F VII, Ne VIII, Na IX, Mg X, Al XI, Si XII, S XIV, Ar XVI, Ca XIII, Ti XX, Cr XXII, and Ni XXVI. About one hundred bound fine structure energy levels of total angular momenta, 1/2 <= J <= 17/2 of even and odd parities, total orbital angular momentum, 0 <= L <= 9 and spin multiplicity (2S + 1) = 2, 4 are obtained for each ion. The levels provide almost 900 allowed bound-bound transitions. The BPRM method enables consideration of large set of transitions with uniform accuracy compared to the best available theoretical methods. The CC eigenfunction expansion for each ion includes the lowest 17 fine structure energy levels of the core configurations 1s2, 1s2s, 1s2p, 1s3s, 1s3p, and 1s3d. The calculated energies of the ions agree with the measured values to within 1% for most levels. The transition probabilities show good agreement with the best available calculated values. The results provide the largest sets of energy levels and transition rates for the ions and are expected to be useful in the analysis of X-ray and EUV spectra from astrophysical sources. Complete electronic files for energies (e.g. Tables 3a and 3b) and transition probabilities (e.g. Table 7) are available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5)} or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/389/716

Nahar, S. N.

2002-07-01

181

The Bayer Facts of Science Education XVI: US STEM Workforce Shortage— Myth or Reality? Fortune 1000 Talent Recruiters on the Debate  

NASA Astrophysics Data System (ADS)

A major debate is currently underway in the USA about whether there is, in fact, a science, technology, engineering and mathematics (STEM) workforce shortage in the country or not. This is the subject of the Bayer Facts of Science Education XVI: US STEM Workforce Shortage—Myth or Reality? Fortune 1000 Talent Recruiters on the Debate. An ongoing public opinion research project commissioned by Bayer Corporation, the Bayer Facts surveys examine US STEM education, diversity and workforce issues. The 16th in the series, the newest survey asks talent recruiters at some of the country's largest employers—those included in the Fortune 1000—to weigh in on current and future demand for new hires with 2- and 4-year STEM degrees. As professionals responsible for scouting, recruiting and hiring talent at Fortune 1000 companies, both STEM and non-STEM alike, these individuals are on the frontlines, tasked with assessing and filling their companies' workforce needs. The survey asks the recruiters whether new hires with 2- and 4-year STEM degrees are as, more or less in demand than their peers without STEM degrees? Are more new STEM jobs being created at their companies than non-STEM jobs? Can they find adequate numbers of qualified candidates in a timely manner and how fierce is the competition for STEM degree holders? To answer these and other questions, the survey polled 150 talent recruiters at Fortune 1000 companies, both STEM and non-STEM alike. The survey also asks the recruiters about diversion in STEM, workforce diversity in the pipeline, the role of community colleges in developing the STEM pipeline and the desired skills and competencies of new hires.

Bayer Corporation

2014-10-01

182

Dinitroso and polynitroso compounds  

PubMed Central

The growing interest in the chemistry of C-nitroso compounds (RN=O; R = alkyl or aryl group) is due in part to the recognition of their participation in various metabolic processes of nitrogen-containing compounds. C-Nitroso compounds have a rich organic chemistry in their own right, displaying interesting intra- and intermolecular dimerization processes and addition reactions with unsaturated compounds. In addition, they have a fascinating coordination chemistry. While most of the attention has been directed towards C-nitroso compounds containing a single –NO moiety, there is an emerging area of research dealing with dinitroso and polynitroso compounds. In this critical review, we present and discuss the synthetic routes and properties of these relatively unexplored dinitroso and polynitroso compounds, and suggest areas of further development involving these compounds. (126 references.) PMID:16100619

Gowenlock, Brian G.; Richter-Addo, George B.

2005-01-01

183

Compounds affecting cholesterol absorption  

NASA Technical Reports Server (NTRS)

A class of novel compounds is described for use in affecting lymphatic absorption of cholesterol. Compounds of particular interest are defined by Formula I: ##STR1## or a pharmaceutically acceptable salt thereof.

Hua, Duy H. (Inventor); Koo, Sung I. (Inventor); Noh, Sang K. (Inventor)

2004-01-01

184

Micromechanical calorimetric sensor  

DOEpatents

A calorimeter sensor apparatus is developed utilizing microcantilevered spring elements for detecting thermal changes within a sample containing biomolecules which undergo chemical and biochemical reactions. The spring element includes a bimaterial layer of chemicals on a coated region on at least one surface of the microcantilever. The chemicals generate a differential thermal stress across the surface upon reaction of the chemicals with an analyte or biomolecules within the sample due to the heat of chemical reactions in the sample placed on the coated region. The thermal stress across the spring element surface creates mechanical bending of the microcantilever. The spring element has a low thermal mass to allow detection and measuring of heat transfers associated with chemical and biochemical reactions within a sample placed on or near the coated region. A second surface may have a different material, or the second surface and body of microcantilever may be of an inert composition. The differential thermal stress between the surfaces of the microcantilever create bending of the cantilever. Deflections of the cantilever are detected by a variety of detection techniques. The microcantilever may be approximately 1 to 200 .mu.m long, approximately 1 to 50 .mu.m wide, and approximately 0.3 to 3.0 .mu.m thick. A sensitivity for detection of deflections is in the range of 0.01 nanometers. The microcantilever is extremely sensitive to thermal changes in samples as small as 30 microliters.

Thundat, Thomas G. (Knoxville, TN); Doktycz, Mitchel J. (Knoxville, TN)

2000-01-01

185

Calorimetric system and method  

DOEpatents

Apparatus is described for measuring heat capacity of a sample where a series of measurements are taken in succession comprises a sample holder in which a sample to be measured is disposed, a temperature sensor and sample heater for providing a heat pulse thermally connected to the sample, and an adiabatic heat shield in which the sample holder is positioned and including an electrical heater. An electrical power supply device provides an electrical power output to the sample heater to generate a heat pulse. The electrical power from a power source to the heat shield heater is adjusted by a control device, if necessary, from one measurement to the next in response to a sample temperature-versus-time change determined before and after a previous heat pulse to provide a subsequent sample temperature-versus-time change that is substantially linear before and after the subsequent heat pulse. A temperature sensor is used and operable over a range of temperatures ranging from approximately 3K to 350K depending upon the refrigerant used. The sample optionally can be subjected to dc magnetic fields such as from 0 to 12 Tesla (0 to 120 kOe). 18 figs.

Gschneidner, K.A. Jr.; Pecharsky, V.K.; Moorman, J.O.

1998-09-15

186

Calorimetric system and method  

DOEpatents

Apparatus for measuring heat capacity of a sample where a series of measurements are taken in succession comprises a sample holder in which a sample to be measured is disposed, a temperature sensor and sample heater for providing a heat pulse thermally connected to the sample, and an adiabatic heat shield in which the sample holder is positioned and including an electrical heater. An electrical power supply device provides an electrical power output to the sample heater to generate a heat pulse. The electrical power from a power source to the heat shield heater is adjusted by a control device, if necessary, from one measurement to the next in response to a sample temperature-versus-time change determined before and after a previous heat pulse to provide a subsequent sample temperature-versus-time change that is substantially linear before and after the subsequent heat pulse. A temperature sensor is used and operable over a range of temperatures ranging from approximately 3K to 350K depending upon the refrigerant used. The sample optionally can be subjected to dc magnetic fields such as from 0 to 12 Tesla (0 to 120 kOe).

Gschneidner, Jr., Karl A. (Ames, IA); Pecharsky, Vitalij K. (Ames, IA); Moorman, Jack O. (Boone, IA)

1998-09-15

187

Calorimetric, X-Ray Diffraction, and Spectroscopic Studies of the Thermotropic Phase Behavior and Organization of Tetramyristoyl Cardiolipin Membranes  

PubMed Central

The thermotropic phase behavior and organization of aqueous dispersions of the quadruple-chained, anionic phospholipid tetramyristoyl diphosphatidylglycerol or tetramyristoyl cardiolipin (TMCL) was studied by differential scanning calorimetry, x-ray diffraction, 31P NMR, and Fourier-transform infrared (FTIR) spectroscopy. At physiological pH and ionic strength, our calorimetric studies indicate that fully equilibrated aqueous dispersions of TMCL exhibit two thermotropic phase transitions upon heating. The lower temperature transition is much less cooperative but of relatively high enthalpy and exhibits marked cooling hysteresis, whereas the higher temperature transition is much more cooperative and also exhibits a relatively high enthalpy but with no appreciable cooling hysteresis. Also, the properties of these two-phase transitions are sensitive to the ionic strength of the dispersing buffer. Our spectroscopic and x-ray diffraction data indicate that the lower temperature transition corresponds to a lamellar subgel (Lc?) to gel (L?) phase transition and the higher temperature endotherm to a L? to lamellar liquid-crystalline (L?) phase transition. At the Lc?/L? phase transition, there is a fivefold increase of the thickness of the interlamellar aqueous space from ?11 Å to ?50 Å, and this value decreases slightly at the L?/L? phase transition. The bilayer thickness (i.e., the mean phosphate-phosphate distance across the bilayer) increases from 42.8 Å to 43.5 Å at the Lc?/L? phase transition, consistent with the loss of the hydrocarbon chain tilt of ?12°, and decreases to 37.8 Å at the L?/L? phase transition. The calculated cross-sectional areas of the TMCL molecules are ?79 Å2 and ?83 Å2 in the Lc? and L? phases, respectively, and we estimate a value of ?100 Å2 in the L? phase. The combination of x-ray and FTIR spectroscopic data indicate that in the Lc? phase, TMCL molecules possess tilted all-trans hydrocarbon chains packed into an orthorhombic subcell in which the zig-zag planes of the chains are parallel, while in the L? phase the untilted, all-trans hydrocarbon chains possess rotational mobility and are packed into a hexagonal subcell, as are the conformationally disordered hydrocarbon chains in the L? phase. Our FTIR spectroscopic results demonstrate that the four carbonyl groups of the TMCL molecule become progressively more hydrated as one proceeds from the Lc? to the L? and then to the L? phase, while the two phosphate moieties of the polar headgroup are comparably well hydrated in all three phases. Our 31P-NMR results indicate that although the polar headgroup retains some mobility in the Lc? phase, its motion is much more restricted in the L? and especially in the L? phase than that of other phospholipids. We can explain most of our experimental results on the basis of the relatively small size of the polar headgroup of TMCL relative to other phospholipids and the covalent attachment of the two phosphate moieties to a single glycerol moiety, which results in a partially immobilized polar headgroup that is more exposed to the solvent than in other glycerophospholipids. Finally, we discuss the biological relevance of the unique properties of TMCL to the structure and function of cardiolipin-containing biological membranes. PMID:17293402

Lewis, Ruthven N. A. H.; Zweytick, Dagmar; Pabst, Georg; Lohner, Karl; McElhaney, Ronald N.

2007-01-01

188

XAFS Model Compound Library  

DOE Data Explorer

The XAFS Model Compound Library contains XAFS data on model compounds. The term "model" compounds refers to compounds of homogeneous and well-known crystallographic or molecular structure. Each data file in this library has an associated atoms.inp file that can be converted to a feff.inp file using the program ATOMS. (See the related Searchable Atoms.inp Archive at http://cars9.uchicago.edu/~newville/adb/) This Library exists because XAFS data on model compounds is useful for several reasons, including comparing to unknown data for "fingerprinting" and testing calculations and analysis methods. The collection here is currently limited, but is growing. The focus to date has been on inorganic compounds and minerals of interest to the geochemical community. [Copied, with editing, from http://cars9.uchicago.edu/~newville/ModelLib/

Newville, Matthew

189

Development of a new type of high pressure calorimetric cell, mechanically agitated and equipped with a dynamic pressure control system: Application to the characterization of gas hydrates  

SciTech Connect

A novel prototype of calorimetric cell has been developed allowing experiments under pressure with an in situ agitation system and a dynamic control of the pressure inside the cell. The use of such a system opens a wide range of potential practical applications for determining properties of complex fluids in both pressurized and agitated conditions. The technical details of this prototype and its calibration procedure are described, and an application devoted to the determination of phase equilibrium and phase change enthalpy of gas hydrates is presented. Our results, obtained with a good precision and reproducibility, were found in fairly good agreement with those found in literature, illustrate the various interests to use this novel apparatus.

Plantier, F., E-mail: frederic.plantier@univ-pau.fr; Missima, D.; Torré, J.-P. [Univ Pau and Pays Adour, CNRS, TOTAL - UMR 5150 – LFC-R - Laboratoire des Fluides Complexes et leurs Réservoirs, BP 1155 – PAU, F-64013 (France)] [Univ Pau and Pays Adour, CNRS, TOTAL - UMR 5150 – LFC-R - Laboratoire des Fluides Complexes et leurs Réservoirs, BP 1155 – PAU, F-64013 (France); Marlin, L. [Univ Pau and Pays Adour, IPRA FR2952 - Fédération de Recherche- Atelier de Physique Générale, BP 1155 – PAU, F-64013 (France)] [Univ Pau and Pays Adour, IPRA FR2952 - Fédération de Recherche- Atelier de Physique Générale, BP 1155 – PAU, F-64013 (France)

2013-12-15

190

Spectral-based calorimetric calibration of a 3CCD color camera for fast and accurate characterization and calibration of LCD displays  

NASA Astrophysics Data System (ADS)

LCD displays exhibit significant amount of variability in their tone-responses, color responses and backlight-modulation responses. LCD display characterization and calibration using a spectrometer or a color meter, however, leads to two basic deficiencies: (a) It can only generate calibration data based on a single spot on the display (usually at panel center); and (b) It generally takes a significant amount of time to do the required measurement. As a result, a fast and efficient system for a full LCD display characterization and calibration is required. Herein, a system based on a 3CCD calorimetrically-calibrated camera is presented which can be used for full characterization and calibration of LCD displays. The camera can provide full tri-stimulus measurements in real time. To achieve high-degree of accuracy, colorimetric calibration of camera is carried out based on spectral method.

Safaee-Rad, Reza; Aleksic, Milivoje

2011-03-01

191

Search for low-mass weakly interacting massive particles using voltage-assisted calorimetric ionization detection in the SuperCDMS experiment.  

PubMed

SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of 170??eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6??GeV/c2. PMID:24580434

Agnese, R; Anderson, A J; Asai, M; Balakishiyeva, D; Basu Thakur, R; Bauer, D A; Billard, J; Borgland, A; Bowles, M A; Brandt, D; Brink, P L; Bunker, R; Cabrera, B; Caldwell, D O; Cerdeno, D G; Chagani, H; Cooley, J; Cornell, B; Crewdson, C H; Cushman, P; Daal, M; Di Stefano, P C F; Doughty, T; Esteban, L; Fallows, S; Figueroa-Feliciano, E; Godfrey, G L; Golwala, S R; Hall, J; Harris, H R; Hertel, S A; Hofer, T; Holmgren, D; Hsu, L; Huber, M E; Jastram, A; Kamaev, O; Kara, B; Kelsey, M H; Kennedy, A; Kiveni, M; Koch, K; Loer, B; Lopez Asamar, E; Mahapatra, R; Mandic, V; Martinez, C; McCarthy, K A; Mirabolfathi, N; Moffatt, R A; Moore, D C; Nadeau, P; Nelson, R H; Page, K; Partridge, R; Pepin, M; Phipps, A; Prasad, K; Pyle, M; Qiu, H; Rau, W; Redl, P; Reisetter, A; Ricci, Y; Saab, T; Sadoulet, B; Sander, J; Schneck, K; Schnee, R W; Scorza, S; Serfass, B; Shank, B; Speller, D; Villano, A N; Welliver, B; Wright, D H; Yellin, S; Yen, J J; Young, B A; Zhang, J

2014-01-31

192

Calorimetric Studies of the Energetics of Order-Disorder in the System Mg(1-x)Fe(x)Ca(CO(3))(2)  

SciTech Connect

Calorimetric studies by Chai and Navrotsky (1996) on dolomite-ankerite energetic have been extended by including two additional types of samples: a very disordered stoichiometric MgCa(CO{sub 3}){sub 2} prepared from low temperature aqueous solution and three largely ordered natural samples of intermediate iron content. Combining these data with previous work, three distinct trends of energetic can be seen: those for samples with nearly complete order, nearly complete disorder, and intermediate order. From these trends, the enthalpy of complete disordering is estimated to be 33 {+-} 6 kJ/mol for MgCa(CO{sub 3}){sub 2} and 18 {+-} 5 kJ/mol for FeCa(CO{sub 3}){sub 2}.

Brady, P.; Dooley, D.; Navrotsky, A.; Reeder, R.

1999-02-10

193

Preparation of uranium compounds  

DOEpatents

UI.sub.3(1,4-dioxane).sub.1.5 and UI.sub.4(1,4-dioxane).sub.2, were synthesized in high yield by reacting turnings of elemental uranium with iodine dissolved in 1,4-dioxane under mild conditions. These molecular compounds of uranium are thermally stable and excellent precursor materials for synthesizing other molecular compounds of uranium including alkoxide, amide, organometallic, and halide compounds.

Kiplinger, Jaqueline L; Montreal, Marisa J; Thomson, Robert K; Cantat, Thibault; Travia, Nicholas E

2013-02-19

194

Analyzing Cranberry Bioactive Compounds  

Microsoft Academic Search

There is a growing public interest for the North American cranberry (Vaccinium macrocarpon) as a functional food because of the potential health benefits linked to phytochemical compounds present in the fruit—the anthocyanin pigments, responsible for its brilliant red color, and other secondary plant metabolites (flavonols, flavan-3-ols, proanthocyanidins, and phenolic acid derivatives). Isolation of these phenolic compounds and flavonoids from a

J. Côté; S. Caillet; G. Doyon; J.-F Sylvain; M. Lacroix

2010-01-01

195

Toxicity of nitroaromatic compounds  

SciTech Connect

The contents of this book include: Sex, Strain, and Species Differences in the Response of Rodents to Nitrobenzene Vapors; The Hepatocarcinogenicity of Dinitrotoluenes; Free Radical Mechanism of Nitroreductase; Use of an In Vivo DNA Repair Assay in the Study of Genotoxicity of Nitroaromatic Compounds; and Possible Models for Risk Assessment of Nitroaromatic Compounds.

Rickert, D.E.

1985-01-01

196

Edheads: The Compound Machine  

NSDL National Science Digital Library

This resource is a collection of interactive animations designed to help kids learn how forces and simple machines can work together to create the compound machine. Child-centered animated activities enhance understanding of how compound machines function and how they are differentiated from simple machines. Additionally the site includes a glossary of important terms, lesson plans, a teacher's guide and information about professionals who work with compound machines. This page is part of a larger collection of animated education resources for the elementary level.

2007-09-18

197

CHAPTER XVI TUNICATES AND LANCELETS  

E-print Network

or hard skeletal parts, they have not left recognizable fossils. Though of very minor economic importance to the numerous zooids and often have much superficial likeness to the sponges in association with which they very

198

Computational Reality XVI Temperature dependency  

E-print Network

dependency of the coefficients From a thermodynamical point of view, as introduced in Comp.Real.X, the changeU = ij dji + T dS , (1) where the Cauchy stress tensor, Euler-Almansi strain tensor, absolute temperature the reference temperature Tref.. For "semi-solid" or "fluid-like" materials, such as polymer melts, cosmetic

Berlin,Technische Universität

199

Heart testing compound  

DOEpatents

The compound 15-(p-[.sup.125 I]-iodophenyl)-6-tellurapentadecanoic acid is disclosed as a myocardial imaging agent having rapid and pronounced uptake, prolonged myocardial retention, and low in vivo deiodination.

Knapp, Jr., Furn F. (Oak Ridge, TN); Goodman, Mark M. (Knoxville, TN)

1985-01-01

200

Heart testing compound  

DOEpatents

The compound 15-(p-(/sup 125/I)-iodophenyl)-6-tellurapentadecanoic acid is disclosed as a myocardial imaging agent having rapid and pronounced uptake, prolonged myocardial retention, and low in vivo deiodination.

Knapp, F.F. Jr.; Goodman, M.M.

1983-06-29

201

Ringed-Carbon Compounds  

NSDL National Science Digital Library

In this interactive activity adapted from NOVA, learn about alkaloids and steroids, both examples of compounds with carbon rings. Short videos with interviews,animations, and photographs are featured.

Foundation, Wgbh E.

2007-02-12

202

Effects of methoxy and formyl substituents on the energetics and reactivity of ?-naphthalenes: a calorimetric and computational study.  

PubMed

A combined experimental and computational study was developed to evaluate and understand the energetics and reactivity of formyl and methoxy ?-naphthalene derivatives. Static bomb combustion calorimetry and the Calvet microcalorimetry were the experimental techniques used to determine the standard (p(o)=0.1 MPa) molar enthalpies of formation, in the liquid phase, ?fHm(o)(l), and of vaporization, ?l(g)Hm(o), at T=298.15K, respectively, of the two liquid naphthalene derivatives. Those experimental values were used to derive the values of the experimental standard molar enthalpies of formation, in the gaseous phase, ?fHm(o)(g), of 1-methoxynaphthalene, (-3.0 ± 3.1)kJmol(-1), and of 1-formylnaphthalene, (36.3 ± 4.1)kJ mol(-1). High-level quantum chemical calculations at the composite G3(MP2)//B3LYP level were performed to estimate the values of the ?fHm(o)(g) of the two compounds studied resulting in values in very good agreement with experimental ones. Natural bond orbital (NBO) calculations were also performed to determine more about the structure and reactivity of this class of compounds. PMID:24444416

Silva, Ana L R; Freitas, Vera L S; Ribeiro da Silva, Maria D M C

2014-07-01

203

Nonpost mold cure compound  

NASA Astrophysics Data System (ADS)

The recent low price trend of electronic products has made IC manufacturing efficiency a top priority in the semiconductor industry. Post mold cure (PMC) process, which generally involves heating the packages in the oven at 175 C for 4 to 8 hours, takes up much longer time than most other assembly processes. If this PMC process can be reduced or eliminated, semiconductor makers will be rewarded with a much higher cost merit. We define the purpose of Non-PMC as 'to get high reliability with suitable physical and electrical properties without PMC'. We compared carious properties of molding compound before and after PMC. We found that curing reaction has almost complete through DSC and C-NMR measurement, but several properties have not stabilized yet, and that not all properties after PMC were better than before PMC. We developed new grade of molding compound considering these facts. And we found that main factors to accomplish non-PMC compound are curability and flowability, and more, increasing of fundamental properties. To accomplish non-PMC, at first, molding compound need to have very high curability. Generally speaking, too high curability causes low flowability, and causes incomplete filing, wire sweep, pad shift, and weak adhesion to inner parts of IC packages. To prevent these failures, various compound properties were studied, and we achieved in adding good flowability to very high curable molding compound. Finally, anti-popcorn property was improved by adding low moisture, high adhesion, high Tg, and high flexural strengths at high temperature. Through this study, we developed new compound grade for various package, especially large QFP using standard ECN resin.

Hirata, Akihiro

1997-08-01

204

Calorimetric and computational study of 1,3-dithiacyclohexane 1,1-dioxide (1,3-dithiane sulfone).  

PubMed

The enthalpies of combustion and sublimation of 1,3-dithiacyclohexane 1,1-dioxide (1,3-dithiane sulfone) were measured by a rotating-bomb combustion calorimeter and the Knudsen effusion technique, and the gas-phase enthalpy of formation was determined, Delta(f)H(m)*(g) = -326.3 +/- 2.0 kJ mol(-1). Standard ab initio molecular orbital calculations at the G2(MP2) level were performed, and a theoretical study on molecular and electronic structure of the compound has been carried out. Calculated Delta(f)H(m)*(g) values agree very well with the experimental one. These experimental and theoretical studies support the relevance of the repulsive electrostatic interaction between sulfur atoms in 1,3-dithiane sulfone, that apparently counterbalances any n(S) --> rho(C-SO2)* stabilizing hyperconjugative interaction. PMID:14987027

Roux, María Victoria; Temprado, Manuel; Jiménez, Pilar; Notario, Rafael; Guzmán-Mejía, Ramón; Juaristi, Eusebio

2004-03-01

205

Compound management beyond efficiency.  

PubMed

Codeveloping alongside chemistry and in vitro screening, compound management was one of the first areas in research recognizing the need for efficient processes and workflows. Material management groups have centralized, automated, miniaturized and, importantly, found out what not to do with compounds. While driving down cost and improving quality in storage and processing, researchers still face the challenge of interfacing optimally with changing business processes, in screening groups, and with external vendors and focusing on biologicals in many companies. Here we review our strategy to provide a seamless link between compound acquisition and screening operations and the impact of material management on quality of the downstream processes. Although this is driven in part by new technologies and improved quality control within material management, redefining team structures and roles also drives job satisfaction and motivation in our teams with a subsequent positive impact on cycle times and customer feedback. PMID:19502566

Burr, Ian; Winchester, Toby; Keighley, Wilma; Sewing, Andreas

2009-06-01

206

Metalloid compounds as drugs  

PubMed Central

The six elements commonly known as metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium. Metalloid containing compounds have been used as antiprotozoal drugs. Boron-based drugs, the benzoxaboroles have been exploited as potential treatments for neglected tropical diseases. Arsenic has been used as a medicinal agent and arsphenamine was the main drug used to treat syphilis. Arsenic trioxide has been approved for the treatment of acute promyelocytic leukemia. Pentavalent antimonials have been the recommended drug for visceral leishmaniasis and cutaneous leishmaniasis. Tellurium (IV) compounds may have important roles in thiol redox biological activity in the human body, and ammonium trichloro (dioxoethylene-O, O’-)tellurate (AS101) may be a promising agent for the treatment of Parkinson’s disease. Organosilicon compounds have been shown to be effective in vitro multidrug-resistance reverting agents. PMID:24019824

Sekhon, B. S.

2013-01-01

207

Sulfur compounds in coal  

NASA Technical Reports Server (NTRS)

The literature on the chemical structure of the organic sulfur compounds (or functional groups) in coal is reviewed. Four methods were applied in the literature to study the sulfur compounds in coal: direct spectrometric and chemical analysis, depolymerization in drastic conditions, depolymerization in mild conditions, and studies on simulated coal. The data suggest that most of the organic sulfur in coal is in the form of thiophenic structures and aromatic and aliphatic sulfides. The relative abundance of the sulfur groups in bituminous coal is estimated as 50:30:20%, respectively. The ratio changes during processing and during the chemical analysis. The main effects are the transformation during processing of sulfides to the more stable thiophenic compounds and the elimination of hydrogen sulfide.

Attar, A.; Corcoran, W. H.

1977-01-01

208

Electrical properties, phase transitions and conduction mechanisms of the [(C2H5)NH3]2CdCl4 compound  

NASA Astrophysics Data System (ADS)

The [(C2H5)NH3]2CdCl4 hybrid material was prepared and its calorimetric study and electric properties were investigated at low temperature. The X-ray powder diffractogram has shown that the compound is crystallized in the orthorhombic system with Abma space group, and the refined unit cell parameters are a=7.546 Å, b=7.443 Å, and c=21.831 Å. The calorimetric study has revealed two endothermic peaks at 216 K and 357 K, which are confirmed by the variation of fp and ?dc as a function of temperature. The equivalent circuit based on the Z-View-software was proposed and the conduction mechanisms were determined. The obtained results have been discussed in terms of the correlated barrier hopping model (CBH) in phase I (low temperature (OLT)), non-overlapping small polaron tunneling model (NSPT) in phase II (room temperature (ORT)) and the overlapping large polaron tunneling model in phase III (high temperature (OHT)). The density of localized states NF(E) at the Fermi level and the binding energy Wm were calculated. The variation of the dielectric loss log(??) with log(?) was found to follow the empirical law, ??=B ?m(T).

Mohamed, C. Ben; Karoui, K.; Saidi, S.; Guidara, K.; Rhaiem, A. Ben

2014-10-01

209

Calorimetric study of crystal growth of ice in hydrated methemoglobin and of redistribution of the water clusters formed on melting the ice.  

PubMed Central

Calorimetric studies of the melting patterns of ice in hydrated methemoglobin powders containing between 0.43 and 0.58 (g water)/(g protein), and of their dependence on annealing at subzero temperatures and on isothermal treatment at ambient temperature are reported. Cooling rates were varied between approximately 1500 and 5 K min-1 and heating rate was 30 K min-1. Recrystallization of ice during annealing is observed at T > 228 K. The melting patterns of annealed samples are characteristically different from those of unannealed samples by the shifting of the melting temperature of the recrystallized ice fraction to higher temperatures toward the value of "bulk" ice. The "large" ice crystals formed during recrystallization melt on heating into "large" clusters of water whose redistribution and apparent equilibration is followed as a function of time and/or temperature by comparison with melting endotherms. We have also studied the effect of cooling rate on the melting pattern of ice with a methemoglobin sample containing 0.50 (g water)/(g protein), and we surmise that for this hydration cooling at rates of > or = approximately 150 K min-1 preserves on the whole the distribution of water molecules present at ambient temperature. PMID:7819504

Sartor, G; Mayer, E

1994-01-01

210

Interaction of the 5-fluorouracil analog 5-fluoro-2'-deoxyuridine with 'N' and 'B' isoforms of human serum albumin: a spectroscopic and calorimetric study.  

PubMed

Drugs and metabolites are transported in the blood by plasma proteins, such as human serum albumin (HSA). The uridine analog 2'dFUrd, which is a cytotoxic prodrug metabolite of capecitabine, has remarkable activity against solid tumors when administered orally. We report the results of an in vitro experimental study on the interactions of 2'-dFUrd with the N-isoform (at pH 7.4) and B-isoform (at pH 9.0) of HSA, investigated using fluorescence spectroscopy, circular dichroism (CD), isothermal titration calorimetry (ITC), differential scanning calorimetry (DSC), and molecular docking. The binding constant (Kb) was higher for the N-isoform than for the B-isoform. Thermodynamic parameters, such as enthalpy change (?H°), entropy change (?S°), and Gibbs free energy change (?G°), were also calculated for both isoform interactions using calorimetric techniques. The thermostabilities of HSA and the HSA-2'dFUrd complex were found to be higher for the N-isoform. The interaction of 2'dFUrd with HSA was also explored in molecular docking studies, which revealed that 2'dFUrd was bound to the Sudlow site I in subdomain IIA through multiple modes of interaction, such as hydrophobic interactions and hydrogen bonding. These results suggest that 2'dFUrd has higher binding affinity for the N-isoform of HSA. PMID:25141914

Ishtikhar, Mohd; Khan, Shawez; Badr, Gamal; Osama Mohamed, Amany; Hasan Khan, Rizwan

2014-09-30

211

Microoptical compound lens  

DOEpatents

An apposition microoptical compound lens comprises a plurality of lenslets arrayed around a segment of a hollow, three-dimensional optical shell. The lenslets collect light from an object and focus the light rays onto the concentric, curved front surface of a coherent fiber bundle. The fiber bundle transports the light rays to a planar detector, forming a plurality of sub-images that can be reconstructed as a full image. The microoptical compound lens can have a small size (millimeters), wide field of view (up to 180.degree.), and adequate resolution for object recognition and tracking.

Sweatt, William C. (Albuquerque, NM); Gill, David D. (Albuquerque, NM)

2007-10-23

212

Compounding practices in Iran.  

PubMed

This article has been presented by pharmacists of the Razi Hospital Pharmacy, which is located within the Dermatology Center of Tehran University of Medical Sciences in Tehran, Iran, and by members of the staff at the Tehran University of Medical Sciences. Discussed within this article are the legalization and regulation of pharmaceutical compounding in Iran, the restrictions on pharmaceutical compounding, the general equipment used in Iran pharmacies, beyond-use dating/expiration dating, the required pharmacy education, as well as information related specifically to Razi Hospital Pharmacy. PMID:24881113

Goodarzi, Navid; Niknam, Somayeh; Akbarzadeh, Tahmineh; Gholami, Kheirollah

2014-01-01

213

Caulking compound poisoning  

MedlinePLUS

... substances used to seal cracks and holes around windows and other openings. Caulking compound poisoning occurs when someone swallows these substances. This is for information only and not for use in the treatment or management of an actual poison exposure. If ...

214

Compound Poisson process approximation  

Microsoft Academic Search

Compound Poisson processes are often useful as approximate models, when describing the occurrence of rare events. In this paper, we develop a method for showing how close such approximations are. Our approach is to use Stein's method directly, rather than by way of declumping and a marked Poisson process; this has conceptual advantages, but entails technical difficulties. Several applications are

A. D. Barbour; Marianne Månsson

2002-01-01

215

The Onium Compounds  

NASA Astrophysics Data System (ADS)

The onium salts are of a big interest for theoretical and structural chemistry, and for organic synthesis. Some representatives of the group (e.g. ammonium salts) were known from the oldest times. Many onium salts are met the nature: ammonium salts (either as inorganic salts, and organic derivatives, e.g. aminoacids, salts of biogenic amines and alkaloids, etc.); oxonium salts (plant pigments as anthocyans are organic oxonium compounds), etc. In 1894 C. Hartmann and V. Meyer prepared the first iodonium salts - 4-iododiphenyliodonium hydrogensulfate and diphenyliodonium salts, and suggested the ending -onium for all compounds with properties similar to those of ammonium salts. Nowadays onium compounds of almost all nonmetals are synthesised and studied. A great variety of physical methods: diffraction (e.g. XRD) and spectral methods (IR-, NMR-, and UV-spectra), as well as the chemical properties and methods of preparation of onium salts have been used in determination of the structure of these compounds. The application of different onium salts is immense. Ammonium, phosphonium and sulfonium salts are used as phase-transfer catalysts; diazonium salts - for the preparation of dyes, metalochromic and pH-indicators. All the onium salts and especially diazonium and iodonium salts are very useful reagents in organic synthesis.

Tsarevsky, Nicolay V.; Slaveykova, Vera; Manev, Stefan; Lazarov, Dobri

1997-06-01

216

8-fluoropurine compounds  

DOEpatents

An efficient, regiocontrolled approach to the synthesis of 8-fluoropurines by direct fluorination of purines with dilute elemental fluorine, or acetyl hypofluorite, is provided. In a preferred embodiment, a purine compound is dissolved in a polar solvent and reacted with a dilute mixture of F.sub.2 in He or other inert gas.

Barrio, Jorge R. (Agoura Hills, CA); Satyamurthy, Nagichettiar (Los Angeles, CA); Namavari, Mohammad (Los Angeles, CA); Phelps, Michael E. (Encino, CA)

2001-01-01

217

Compound floating pivot micromechanisms  

DOEpatents

A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use compound floating pivot structures to attain far greater tilt angles than are practical using other micromechanical techniques. The new mechanisms are also capable of bi-directional tilt about multiple axes.

Garcia, Ernest J. (Albuquerque, NM)

2001-04-24

218

PERSISTENT PERFLUORINATED ORGANIC COMPOUNDS  

EPA Science Inventory

Perfluorinated compounds (PFCs) have gained notoriety in the recent past. Global distribution of PFCs in wildlife, environmental samples and humans has sparked a recent increase in new investigations concerning PFCs. Historically PFCs have been used in a wide variety of consume...

219

Tagging Classical Sanskrit Compounds  

Microsoft Academic Search

The paper sets out a prima facie case for the claim that the classification of Sanskrit compounds in P??inian tradition can be retrieved from a very slight\\u000a augmentation of the usual enriched context free rules.

Brendan S. Gillon

2009-01-01

220

Studium der Veränderungen bei thermischen und hydrothermischen Vorgängen XVI. Mitteilung Papierchromatographischer Nachweis des bei der thermischen Zersetzung des Natrium-Cyclamats entstehenden Cyclohexylamins  

Microsoft Academic Search

Summary A thermal decomposition of sodium cyclamate was already detected after 60 min of heating at 130° C with formation of cyclohexyl amine. The amount increases with rising temperature, similar the addition of glucose or glycine to cyclamate. The thermal decomposition of cyclamate in presence of glucose is confirmed by the formation of dark coloured compounds, different in their aspect

Jir?í Hrdli?ka; Gustav Janí?ek

1971-01-01

221

Metabolism of nitroaromatic compounds.  

PubMed

There appear to be two major pathways for the metabolism of nitrobenzene and substituted nitrobenzenes. The first of these is reduction of the nitro group to yield aniline or substituted anilines. For nitrobenzene and perhaps for pentachloronitrobenzene, reduction of the nitro group to the amine is accomplished by bacteria of the gastrointestinal tract. Addition of a second nitro group results in easier reduction of one of the nitro groups on dinitrobenzenes, since they can be reduced under aerobic conditions by hepatic and erythrocyte enzymes. Bacterial reduction of the dinitrobenzenes is probably not quantitatively important in vivo. The second pathway is replacement of a nitro group by glutathione. The relative importance of this pathway compared to nitro group reduction depends upon the compound. It has not been demonstrated to occur for nitrobenzene. It is the major route of metabolism for 1,2-dinitrobenzene but is not an important route for 1,3- or 1,4-dinitrobenzene in hepatocytes. Tetrachloronitrobenzene isomers in which the nitro group is flanked by chlorines and pentachloronitrobenzene undergo nitro group replacement, but 2,3,4,5-tetrachloronitrobenzene does not. The most important pathway for the metabolism of mononitrotoluenes is methyl group oxidation. All quantitatively important metabolites are apparently formed from the nitrobenzyl alcohols. The mono- and dinitrotoluenes are not significantly reduced to isolatable metabolites by mammalian enzymes in vivo; intestinal microflora reduce these compounds after biliary excretion of the nitrobenzyl glucuronides. The little available evidence suggests that this is not the case for trinitrotoluenes. Urinary metabolites retain the methyl group and bear one or two amino groups. This suggests either that mammalian enzymes are capable of reducing the nitro groups of trinitrotoluenes in vivo or that intestinal microflora gain access to unmodified trinitrotoluene. The nitropolycyclic aromatic hydrocarbons are apparently metabolized by both nitro reduction and ring oxidation. There is good evidence, at least for 1-nitropyrene and 6-nitrobenzo[a]pyrene, that nitro reduction occurs in intestinal microflora. the complexities of foreign compound metabolism are well illustrated by the biotransformation of the nitroaromatic compounds. Positional isomers are preferentially metabolized by markedly different pathways. Substitution to different degrees or with different functional groups greatly affects the types of metabolites formed. Yet these compounds also offer opportunities for understanding the mechanisms of foreign compound metabolism.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3311683

Rickert, D E

1987-01-01

222

Organic compounds in meteorites  

NASA Technical Reports Server (NTRS)

Recent studies of carbonaceous chondrites provide evidence that certain organic compounds are indigenous and the result of an abiotic, chemical synthesis. The results of several investigators have established the presence of amino acids and precursors, mono- and dicarboxylic acids, N-heterocycles, and hydrocarbons as well as other compounds. For example, studies of the Murchison and Murray meteorites have revealed the presence of at least 40 amino acids with nearly equal abundances of D and L isomers. The population consists of both protein and nonprotein amino acids including a wide variety of linear, cyclic, and polyfunctional types. Results show a trend of decreasing concentration with increasing carbon number, with the most abundant being glycine (41 n Moles/g). These and other results to be reviewed provide persuasive support for the theory of chemical evolution and provide the only natural evidence for the protobiological subset of molecules from which life on earth may have arisen.

Lawless, J. G.

1980-01-01

223

Oral compound nevus.  

PubMed

The melanocytic nevus is a benign and focal proliferation of nevus cells that can be congenital or acquired. Intraoral lesions are uncommon, and the etiology and pathogenesis are poorly understood. The occurrence rate of oral compound nevus is about 5.9% to 16.5% of all oral melanocytic nevi. A 22-year-old male patient presented with a dark brown macule on the buccal mucosa of the maxilla in the region of tooth 26. The lesion was elliptical, 0.7 x 0.5 cm, well circumscribed, asymptomatic, and the evolution time was unknown. An excisional biopsy was performed and microscopic analysis revealed nests of nevus cells in the epithelium and underlying connective tissue that were compatible with melanocytic compound nevus. Owing to the clinical similarity between oral melanocytic nevus and oral melanoma, a histopathological analysis is mandatory for definitive diagnosis. PMID:24612575

Cardoso, Lyzete Berriel; Consalaro, Alberto; da Silva Santos, Paulo Sérgio; da Silva Sampieri, Marcelo Bonifácio; Tinoco-Araújo, José Endrigo

2014-02-01

224

Compound in Cubic Phase  

NASA Astrophysics Data System (ADS)

In this paper, electronic band structure, total density of states, and optical, lattice dynamic and thermo-dynamic properties of BaCeO3 compound in cubic phase were investigated using density functional theory within the generalized gradient approximation. The calculated lattice constant is consistent with the experimental result. In cubic phase, BaCeO3 has a semiconductor character with 2.17 eV band gap.

Aycibin, Murat; Erdinc, Bahattin; Akkus, Harun

2014-11-01

225

Immunomodulating compounds in Basidiomycetes  

PubMed Central

Mushrooms are distinguished as important food containing immunomodulating and anticancer agents. These compounds belong mostly to polysaccharides especially ?-d-glucans. Among them, ?-1,3-glucan with side chain ?-1,6-glucose residues have more important roles in immunomodulating and antitumor activities. In this review, we have introduced polysaccharide mainly from Lentinula edodes and Agaricus blazei Murill with immunomodulating and antitumor activities. In addition, the mechanism of activation of immune response and signal cascade are also reviewed. PMID:23704809

Mizuno, Masashi; Nishitani, Yosuke

2013-01-01

226

Compound semiconductor SPAD arrays  

NASA Astrophysics Data System (ADS)

Single photon avalanche diodes (SPADs) are revolutionizing ultra-sensitive photodetection applications, providing single photon sensitivity, high quantum efficiency and low dark noise at or near room temperature. When aggregated into arrays, these devices have demonstrated the ability to operate as photon number resolving detectors with wide dynamic range, or as single-photon imaging detectors. SPAD array performance has reached a point where replacing vacuum tube based MCP and PMT photodetectors for most applications is inevitable. Compound semiconductor SPAD arrays offer the unique proposition to tailor performance to match application specific wavelength, speed and radiation hardness requirements. We present a theoretical framework describing performance limits to compound semiconductor SPAD arrays and our latest experimental results detailing the performance of GaAs SPAD arrays. These devices achieve nanosecond rise and fall times, excellent photon number resolving capability, and low dark count rates. Single photon number resolving is demonstrated with 4% single photon detection efficiency at room temperature with dark count rates below 7 Mcps/mm2. Compound semiconductor SPAD arrays have the opportunity to provide orders of magnitude improvement in dark count rate and radiation hardness over silicon SPAD arrays, as well as the ability to detect wavelengths where silicon is blind.

Harmon, Eric S.; Naydenkov, Mikhail; Hyland, James T.

2013-06-01

227

Toxic compounds in honey.  

PubMed

There is a wealth of information about the nutritional and medicinal properties of honey. However, honey may contain compounds that may lead to toxicity. A compound not naturally present in honey, named 5-hydroxymethylfurfural (HMF), may be formed during the heating or preservation processes of honey. HMF has gained much interest, as it is commonly detected in honey samples, especially samples that have been stored for a long time. HMF is a compound that may be mutagenic, carcinogenic and cytotoxic. It has also been reported that honey can be contaminated with heavy metals such as lead, arsenic, mercury and cadmium. Honey produced from the nectar of Rhododendron ponticum contains alkaloids that can be poisonous to humans, while honey collected from Andromeda flowers contains grayanotoxins, which can cause paralysis of limbs in humans and eventually leads to death. In addition, Melicope ternata and Coriaria arborea from New Zealand produce toxic honey that can be fatal. There are reports that honey is not safe to be consumed when it is collected from Datura plants (from Mexico and Hungary), belladonna flowers and Hyoscamus niger plants (from Hungary), Serjania lethalis (from Brazil), Gelsemium sempervirens (from the American Southwest), Kalmia latifolia, Tripetalia paniculata and Ledum palustre. Although the symptoms of poisoning due to honey consumption may differ depending on the source of toxins, most common symptoms generally include dizziness, nausea, vomiting, convulsions, headache, palpitations or even death. It has been suggested that honey should not be considered a completely safe food. PMID:24214851

Islam, Md Nazmul; Khalil, Md Ibrahim; Islam, Md Asiful; Gan, Siew Hua

2014-07-01

228

Complex Compound Chemical Heat Pumps  

E-print Network

Complex-compound solid-vapor fluid pairs can be used in heat of reaction heat pumps for temperature amplifier (TA) as well as heat amplifier (HA) cycle configurations. This report describes the conceptual hardware design for complex compound...

Rockenfeller, U.; Langeliers, J.; Horn, G.

229

Color Classification of Coordination Compounds.  

ERIC Educational Resources Information Center

Proposes that colored compounds be classified by reference to a standard color-order system incorporating a color dictionary. Argues that the colors of new compounds could be incorporated into the characterization process and into computer storage systems. (TW)

Poncini, Laurence; Wimmer, Franz L.

1987-01-01

230

Bilingual reading of compound words.  

PubMed

The present study investigated whether bilingual readers activate constituents of compound words in one language while processing compound words in the other language via decomposition. Two experiments using a lexical decision task were conducted with adult Korean-English bilingual readers. In Experiment 1, the lexical decision of real English compound words was more accurate when the translated compounds (the combination of the translation equivalents of the constituents) in Korean (the nontarget language) were real words than when they were nonwords. In Experiment 2, when the frequency of the second constituents of compound words in English (the target language) was manipulated, the effect of lexical status of the translated compounds was greater on the compounds with high-frequency second constituents than on those with low-frequency second constituents in the target language. Together, these results provided evidence for morphological decomposition and cross-language activation in bilingual reading of compound words. PMID:20623255

Ko, In Yeong; Wang, Min; Kim, Say Young

2011-02-01

231

Offset Compound Gear Drive  

NASA Technical Reports Server (NTRS)

The Offset Compound Gear Drive is an in-line, discrete, two-speed device utilizing a special offset compound gear that has both an internal tooth configuration on the input end and external tooth configuration on the output end, thus allowing it to mesh in series, simultaneously, with both a smaller external tooth input gear and a larger internal tooth output gear. This unique geometry and offset axis permits the compound gear to mesh with the smaller diameter input gear and the larger diameter output gear, both of which are on the same central, or primary, centerline. This configuration results in a compact in-line reduction gear set consisting of fewer gears and bearings than a conventional planetary gear train. Switching between the two output ratios is accomplished through a main control clutch and sprag. Power flow to the above is transmitted through concentric power paths. Low-speed operation is accomplished in two meshes. For the purpose of illustrating the low-speed output operation, the following example pitch diameters are given. A 5.0 pitch diameter (PD) input gear to 7.50 PD (internal tooth) intermediate gear (0.667 reduction mesh), and a 7.50 PD (external tooth) intermediate gear to a 10.00 PD output gear (0.750 reduction mesh). Note that it is not required that the intermediate gears on the offset axis be of the same diameter. For this example, the resultant low-speed ratio is 2:1 (output speed = 0.500; product of stage one 0.667 reduction and stage two 0.750 stage reduction). The design is not restricted to the example pitch diameters, or output ratio. From the output gear, power is transmitted through a hollow drive shaft, which, in turn, drives a sprag during which time the main clutch is disengaged.

Stevens, Mark A.; Handschuh, Robert F.; Lewicki, David G.

2010-01-01

232

Boronated porphyrin compounds  

DOEpatents

A compound is described having the structure ##STR1## where R preferably is ##STR2## and most preferably R.sup.3 is a closo-carborane and R.sup.2 is --H, an alkyl or aryl having 1 to about 7 carbon atoms, This invention was made with Government support under NIH Grant No. CA-37961 awarded by the Department of Health and Human Services and under the Associated Universities Inc. Contract No. De-AC02-76CH00016 with the U.S. Department of Energy. The Government has rights in this invention.

Kahl, S.B.; Koo, M.S.

1992-09-22

233

Titanium alkoxide compound  

DOEpatents

A titanium alkoxide composition is provided, as represented by the chemical formula (OC.sub.6H.sub.5N).sub.2Ti(OC.sub.6H.sub.5NH.sub.2).sub.2. As prepared, the compound is a crystalline substance with a hexavalent titanium atom bonded to two OC.sub.6H.sub.5NH.sub.2 groups and two OC.sub.6H.sub.5N groups with a theoretical molecular weight of 480.38, comprising 60.01% C, 5.04% H and 11.66% N.

Boyle, Timothy J. (Albuquerque, NM)

2007-08-14

234

Terahertz plastic compound lenses.  

PubMed

We present terahertz (THz) lenses made of highly refracting polymeric compounds which provide a better focusing performance and an increased functionality in comparison to conventional THz lenses. Using mixtures consisting of polypropylene (PP) and alumina as well as PP and zinc sulfide allows a significant increase of the refractive index while simultaneously keeping a low extinction and dispersion. With these new material combinations, lenses with an increased focusing capability are realized. This is evaluated by focal plane measurements using a fiber coupled THz time-domain spectrometer. PMID:23842159

Wichmann, M; Mondol, A S; Kocic, N; Lippert, S; Probst, T; Schwerdtfeger, M; Schumann, S; Hochrein, T; Heidemeyer, P; Bastian, M; Bastian, G; Koch, M

2013-06-20

235

Phenolic compounds in Catharanthus roseus  

Microsoft Academic Search

Besides alkaloids Catharanthus roseus produces a wide spectrum of phenolic compounds, this includes C6C1 compounds such as 2,3-dihydoxybenzoic acid, as well as\\u000a phenylpropanoids such as cinnamic acid derivatives, flavonoids and anthocyanins. The occurrence of these compounds in C. roseus is reviewed as well as their biosynthesis and the regulation of the pathways. Both types of compounds compete with the indole

Natali Rianika Mustafa; Robert Verpoorte

2007-01-01

236

Prescribing flexibility through prescription compounding  

Microsoft Academic Search

Compounding pharmacists can assist the patients of phy- sicians and other licensed prescribers by providing them with access to unique medications and dosage forms. Phar- macists trained in the art and science of compounding are opening specialty compounding pharmacies to aid those who require individualized medication. A patient in need of a preservative-free medication, a medication that is no longer

Scott Brown

2008-01-01

237

Potential risks of pharmacy compounding.  

PubMed

Pharmacy compounding involves the preparation of customized medications that are not commercially available for individual patients with specialized medical needs. Traditional pharmacy compounding is appropriate when done on a small scale by pharmacists who prepare the medication based on an individual prescription. However, the regulatory oversight of pharmacy compounding is significantly less rigorous than that required for Food and Drug Administration (FDA)-approved drugs; as such, compounded drugs may pose additional risks to patients. FDA-approved drugs are made and tested in accordance with good manufacturing practice regulations (GMPs), which are federal statutes that govern the production and testing of pharmaceutical products. In contrast, compounded drugs are exempt from GMPs, and testing to assess product quality is inconsistent. Unlike FDA-approved drugs, pharmacy-compounded products are not clinically evaluated for safety or efficacy. In addition, compounded preparations do not have standard product labeling or prescribing information with instructions for safe use. Compounding pharmacies are not required to report adverse events to the FDA, which is mandatory for manufacturers of FDA-regulated medications. Some pharmacies engage in activities that extend beyond the boundaries of traditional pharmacy compounding, such as large-scale production of compounded medications without individual patient prescriptions, compounding drugs that have not been approved for use in the US, and creating copies of FDA-approved drugs. Compounding drugs in the absence of GMPs increases the potential for preparation errors. When compounding is performed on a large scale, such errors may adversely affect many patients. Published reports of independent testing by the FDA, state agencies, and others consistently show that compounded drugs fail to meet specifications at a considerably higher rate than FDA-approved drugs. Compounded sterile preparations pose the additional risk of microbial contamination to patients. In the last 11 years, three separate meningitis outbreaks have been traced to purportedly 'sterile' steroid injections contaminated with fungus or bacteria, which were made by compounding pharmacies. The most recent 2012 outbreak has resulted in intense scrutiny of pharmacy compounding practices and increased recognition of the need to ensure that compounding is limited to appropriate circumstances. Patients and healthcare practitioners need to be aware that compounded drugs are not the same as generic drugs, which are approved by the FDA. The risk-benefit ratio of using traditionally compounded medicines is favorable for patients who require specialized medications that are not commercially available, as they would otherwise not have access to suitable treatment. However, if an FDA-approved drug is commercially available, the use of an unapproved compounded drug confers additional risk with no commensurate benefit. PMID:23526368

Gudeman, Jennifer; Jozwiakowski, Michael; Chollet, John; Randell, Michael

2013-03-01

238

Biomimetic microfabricated compound eyes  

NASA Astrophysics Data System (ADS)

Over the past century, compound eyes in nature have been one of the most studied and intriguing topics in physiological optics due to their unique optical scheme for imaging. Hundreds to ten thousands of integrated optical units called ommatidia are spherically arranged along a curvilinear surface and point in different directions. Each ommatidium collects light within a small angular acceptance and collectively they construct a full image with a wide field-of-view. In this work, artificial compound eye lenses with three-dimensional configuration, which are anatomically and functionally similar to those in nature, have been synthesized using a photosensitive polymer resin by utilizing microlens technology, self-written waveguide process, and soft lithography. Replicated honeycomb packed polymer microlenses as substitute for facet lenses in a natural compound eye was microfabricated with a photoresist melting process for microlens templates and a soft lithographic process for polymer replication. The microtemplate of photoresist microlens arrays (F/1 ˜ F/3, DL = 20 ˜ 50 mum) with low Fresnel number (NF < 10) and high packing density was replicated with different polymers such as UV curable epoxy resin, polydimethylsiloxane elastomer, and a negative tone photoresist. Related to ommatidial optics, the diffraction of a low Fresnel number microlens, the light guiding of a waveguide, and the angular acceptance function of a microlens-waveguide system were theoretically studied with numerical analysis. First, as a prototype microfabricated microlens-waveguide system ( DL = 300 mum), a small angular acceptance (rho A = 1.5°) comparable to that of natural ommatidia was experimentally achieved and compared with the numerical analysis. The system is based on self-written waveguides in a photosensitive polymer resin and replicated elastomer microlens arrays. However, due to the technical difficulties in handling the elastomer membrane with microlenses, it is limited in scaling down to the physical dimensions of natural ommatidium. Second, as an advanced development, self-aligned microlens-waveguide systems comparable to the physical dimensions of natural ommatidia have been developed and integrated in a photosensitive resin. The individual microlens-waveguide systems of about 8,370 were spherically arranged along the circumference of a polymer dome of 2.5 mm in diameter and each points in different directions. The spherical configuration was realized using a replication process of reconfigurable microtemplates, i.e. the polymer replication using the deformed elastomer membrane with microlens patterns under small pressure (5 kPa ˜ 20 kPa). The characterizations of the small scale microlenses (F/1.8 ˜ F/2.9, DL = 25 mum) and waveguides were also carried out with a modified reflection/transmission confocal microscope. The comparative discussion between natural and artificial compound eyes is described and several future directions based on this work are also proposed.

Jeong, Ki-Hun

239

Dioxin and Related Compounds  

NSDL National Science Digital Library

This substantial new site, provided by the Environmental Protection Agency's National Center for Environmental Assessment, addresses the mechanism of Dioxin contamination and describes NCEA's Dioxin Reassessment efforts. The site provides full descriptions and molecular graphics of "Dioxins and related compounds" (Furans, PCB's), as well as EPA Summaries on Dioxin exposure, Dioxin risk, and dose response. The Dioxin Exposure Initiative seeks to quantitatively link dioxin sources to general population exposures using "source measurements, environmental media and national food surveys, and fate and transport modeling." Further links to EPA Regulations and EPA Analytical Methods round out the site. Note that many of the documents at the site are available in Adobe Acrobat (.pdf) or WordPerfect format.

1994-01-01

240

Public chemical compound databases.  

PubMed

The internet has rapidly become the first port of call for all information searches. The increasing array of chemistry-related resources that are now available provides chemists with a direct path to the information that was previously accessed via library services and was limited by commercial and costly resources. The diversity of the information that can be accessed online is expanding at a dramatic rate, and the support for publicly available resources offers significant opportunities in terms of the benefits to science and society. While the data online do not generally meet the quality standards of manually curated sources, there are efforts underway to gather scientists together and 'crowdsource' an improvement in the quality of the available data. This review discusses the types of public compound databases that are available online and provides a series of examples. Focus is also given to the benefits and disruptions associated with the increased availability of such data and the integration of technologies to data mine this information. PMID:18428094

Williams, Anthony J

2008-05-01

241

Organic Compounds in Carbonaceous Meteorites  

NASA Technical Reports Server (NTRS)

Carbonaceous meteorites are relatively enriched in soluble organic compounds. To date, these compounds provide the only record available to study a range of organic chemical processes in the early Solar System chemistry. The Murchison meteorite is the best-characterized carbonaceous meteorite with respect to organic chemistry. The study of its organic compounds has related principally to aqueous meteorite parent body chemistry and compounds of potential importance for the origin of life. Among the classes of organic compounds found in Murchison are amino acids, amides, carboxylic acids, hydroxy acids, sulfonic acids, phosphonic acids, purines and pyrimidines (Table 1). Compounds such as these were quite likely delivered to the early Earth in asteroids and comets. Until now, polyhydroxylated compounds (polyols), including sugars (polyhydroxy aldehydes or ketones), sugar alcohols, sugar acids, etc., had not been identified in Murchison. Ribose and deoxyribose, five-carbon sugars, are central to the role of contemporary nucleic acids, DNA and RNA. Glycerol, a three-carbon sugar alcohol, is a constituent of all known biological membranes. Due to the relative lability of sugars, some researchers have questioned the lifetime of sugars under the presumed conditions on the early Earth and postulated other (more stable) compounds as constituents of the first replicating molecules. The identification of potential sources and/or formation mechanisms of pre-biotic polyols would add to the understanding of what organic compounds were available, and for what length of time, on the ancient Earth.

Cooper, Grorge

2001-01-01

242

Micro-machined calorimetric biosensors  

DOEpatents

A method and apparatus are provided for detecting and monitoring micro-volumetric enthalpic changes caused by molecular reactions. Micro-machining techniques are used to create very small thermally isolated masses incorporating temperature-sensitive circuitry. The thermally isolated masses are provided with a molecular layer or coating, and the temperature-sensitive circuitry provides an indication when the molecules of the coating are involved in an enthalpic reaction. The thermally isolated masses may be provided singly or in arrays and, in the latter case, the molecular coatings may differ to provide qualitative and/or quantitative assays of a substance.

Doktycz, Mitchel J. (Knoxville, TN); Britton, Jr., Charles L. (Alcoa, TN); Smith, Stephen F. (Loudon, TN); Oden, Patrick I. (Plano, TX); Bryan, William L. (Knoxville, TN); Moore, James A. (Powell, TN); Thundat, Thomas G. (Knoxville, TN); Warmack, Robert J. (Knoxville, TN)

2002-01-01

243

Antimicrobial compounds in tears.  

PubMed

The tear film coats the cornea and conjunctiva and serves several important functions. It provides lubrication, prevents drying of the ocular surface epithelia, helps provide a smooth surface for refracting light, supplies oxygen and is an important component of the innate defense system of the eye providing protection against a range of potential pathogens. This review describes both classic antimicrobial compounds found in tears such as lysozyme and some more recently identified such as members of the cationic antimicrobial peptide family and surfactant protein-D as well as potential new candidate molecules that may contribute to antimicrobial protection. As is readily evident from the literature review herein, tears, like all mucosal fluids, contain a plethora of molecules with known antimicrobial effects. That all of these are active in vivo is debatable as many are present in low concentrations, may be influenced by other tear components such as the ionic environment, and antimicrobial action may be only one of several activities ascribed to the molecule. However, there are many studies showing synergistic/additive interactions between several of the tear antimicrobials and it is highly likely that cooperativity between molecules is the primary way tears are able to afford significant antimicrobial protection to the ocular surface in vivo. In addition to effects on pathogen growth and survival some tear components prevent epithelial cell invasion and promote the epithelial expression of innate defense molecules. Given the protective role of tears a number of scenarios can be envisaged that may affect the amount and/or activity of tear antimicrobials and hence compromise tear immunity. Two such situations, dry eye disease and contact lens wear, are discussed here. PMID:23880529

McDermott, Alison M

2013-12-01

244

Phenolic compounds in surface water  

Microsoft Academic Search

The presence of phenols in a stream is undesired because of their strong action, their toxicity to fish and unpleasant tastes and odours produced when water containing phenols is chlorinated.The phenolic compounds in the water environment may have a natural, industrial, domestic or agricultural origin.The purpose of this paper is to determine the nature, origin and trend of phenolic compounds

Franco Gnudi

1999-01-01

245

Video: Focusing a Compound Microscope  

NSDL National Science Digital Library

This video from CUNY Kingsborough Community College describes how to focus a compound microscope. The brief clip, available for viewing on YouTube, would be most useful for students with a basic understanding of the parts of a compound microscope and how to use it. Running time for the video is 0:55.

2013-07-01

246

Morphological Dynamics in Compound Processing  

ERIC Educational Resources Information Center

This paper explores the time-course of morphological processing of trimorphemic Finnish compounds. We find evidence for the parallel access to full-forms and morphological constituents diagnosed by the early effects of compound frequency, as well as early effects of left constituent frequency and family size. We also observe an interaction between…

Kuperman, Victor; Bertram, Raymond; Baayen, R. Harald

2008-01-01

247

ATMOSPHERIC FREONS AND HALOGENATED COMPOUNDS  

EPA Science Inventory

Ambient levels of atmospheric Freons, halogenated hydrocarbons, and SF6 were measured at various locations in the U.S.A. Compounds such as CCl3F, CCl2F2, CH3-CCl3, and CCl4 were ubiquitious and generally measured at sub ppb levels. Tropospherically reactive compounds such as C2Cl...

248

Antifungal Compounds from Piper Species  

PubMed Central

This review documents chemical structures and antifungal activities of 68 compounds isolated from 22 Piper species of the plant family Piperaceae. These compounds include amides, flavonoids, prenylated benzoic acid derivatives, lignans, phenylpropanoids, butenolides, and cyclopentendiones. Some of them may serve as leads for potential pharmaceutical or agricultural fungicide development. PMID:24307889

Xu, Wen-Hui; Li, Xing-Cong

2013-01-01

249

Electronic Configuration of Yb Compounds  

Microsoft Academic Search

The total energy differences between divalent and trivalent configurations of Yb ions in a number of Yb compounds are studied. Two different band theoretical methods, which differ in the treatment of the localized f electrons, are used. The results show that in all Yb compounds the valence energy differences are equal to the energy needed to localize an f electron.

W. M. Temmerman; Z. Szotek; A. Svane; P. Strange; H. Winter; A. Delin; B. Johansson; O. Eriksson; L. Fast; J. M. Wills

1999-01-01

250

Bilingual Reading of Compound Words  

ERIC Educational Resources Information Center

The present study investigated whether bilingual readers activate constituents of compound words in one language while processing compound words in the other language via decomposition. Two experiments using a lexical decision task were conducted with adult Korean-English bilingual readers. In Experiment 1, the lexical decision of real English…

Ko, In Yeong; Wang, Min; Kim, Say Young

2011-01-01

251

Devices for collecting chemical compounds  

DOEpatents

A device for sampling chemical compounds from fixed surfaces and related methods are disclosed. The device may include a vacuum source, a chamber and a sorbent material. The device may utilize vacuum extraction to volatilize the chemical compounds from a fixed surface so that they may be sorbed by the sorbent material. The sorbent material may then be analyzed using conventional thermal desorption/gas chromatography/mass spectrometry (TD/GC/MS) instrumentation to determine presence of the chemical compounds. The methods may include detecting release and presence of one or more chemical compounds and determining the efficacy of decontamination. The device may be useful in collection and analysis of a variety of chemical compounds, such as residual chemical warfare agents, chemical attribution signatures and toxic industrial chemicals.

Scott, Jill R; Groenewold, Gary S

2013-12-24

252

Macrocyclic compounds as corrosion inhibitors  

SciTech Connect

The influence of three macrocyclic compounds on corrosion of mild steel (MS) in hydrochloric acid (HCl) was investigated using weight loss, potentiodynamic polarization, alternating current (AC) impedance, and hydrogen permeation techniques. All the investigated compounds showed significant efficiencies and reduced permeation of hydrogen through MS in HCl. Inhibition efficiency (IE) varied with the nature and concentrations of the inhibitors, temperature, and concentrations of the acid solutions. The addition of iodide ions (I{sup {minus}}) increased IE of all the tested compounds as a result of the synergistic effect. Potentiodynamic polarization results revealed that macrocyclic compounds acted as mixed inhibitors in 1 M HCl to 5 M HCl. Adsorption on the metal surface obeyed Temkin`s adsorption isotherm. Auger electron spectroscopy (AES) of the polished MS surface, exposed with tetraphenyldithia-octaazacyclotetradeca-hexaene (PTAT) proved adsorption of this compound on the surface through nitrogen and sulfur atoms.

Quraishi, M.A.; Rawat, J.; Ajmal, M. [Aligarh Muslim Univ., Uttar Pradesh (India)

1998-12-01

253

Polishing compound for plastic surfaces  

DOEpatents

A polishing compound for plastic surfaces. The compound contains by weight approximately 4 to 17 parts at least one petroleum distillate lubricant, 1 to 6 parts mineral spirits, 2.5 to 15 parts abrasive particles, and 2.5 to 10 parts water. The abrasive is tripoli or a similar material that contains fine particles silica. Preferably, most of the abrasive particles are less than approximately 10 microns, more preferably less than approximately 5 microns in size. The compound is used on PLEXIGLAS.TM., LEXAN.TM., LUCITE.TM., polyvinyl chloride (PVC) and similar plastic materials whenever a smooth, clear polished surface is desired.

Stowell, Michael S. (New Ellenton, SC)

1995-01-01

254

Iodimetric determination of organolead compounds.  

PubMed

A sensitive, rapid and accurate titrimetric method has been developed for the determination of 50-5000 mug of ethyl-lead or phenyl-lead compounds, based on their oxidation with a chloroform solution of iodine, removal of the excess of iodine, oxidation of the resulting iodide with bromine, and iodometric titration of the iodate formed. The coefficient of variation does not exceed 1.2% for amounts > 1000 mug of the organolead compound, but increases to 2.8% for the 50-mug level. The ethyl- and phenyl-lead compounds can be determined independently in mixtures. PMID:18964424

Amin, D; Al-Allaf, T A

1987-10-01

255

Compound curvature laser window development  

NASA Technical Reports Server (NTRS)

The NASA Lewis Research Center has developed and implemented a unique process for forming flawless compound curvature laser windows. These windows represent a major part of specialized, nonintrusive laser data acquisition systems used in a variety of compressor and turbine research test facilities. This report summarizes the main aspects of compound curvature laser window development. It is an overview of the methodology and the peculiarities associated with the formulation of these windows. Included in this discussion is new information regarding procedures for compound curvature laser window development.

Verhoff, Vincent G.

1993-01-01

256

Polishing compound for plastic surfaces  

DOEpatents

A polishing compound for plastic surfaces is disclosed. The compound contains by weight approximately 4 to 17 parts at least one petroleum distillate lubricant, 1 to 6 parts mineral spirits, 2.5 to 15 parts abrasive particles, and 2.5 to 10 parts water. The abrasive is tripoli or a similar material that contains colloidal silica. Preferably, most of the abrasive particles are less than approximately 10 microns, more preferably less than approximately 5 microns in size. The compound is used on PLEXIGLAS{sup TM}, LEXAN{sup TM}, LUCITE{sup TM}, polyvinyl chloride (PVC) and similar plastic materials whenever a smooth, clear polished surface is desired.

Stowell, M.S.

1993-01-01

257

Low-temperature heat capacity of diopside glass (CaMgSi2O6): A calorimetric test of the configurational-entropy theory applied to the viscosity of liquid silicates  

USGS Publications Warehouse

Heat-capacity measurements have been made between 8 and 370 K on an annealed and a rapidly quenched diopside glass. Between 15 and 200 K, Cp does not depend significantly on the thermal history of the glass. Below 15 K Cp is larger for the quenched than for the annealed specimen. The opposite is true above 200 K as a result of what is interpreted as a secondary relaxation around room temperature. The magnitude of these effects, however, is small enough that the relative entropies S(298)-S(0) of the glasses differ by only 0.5 J/mol K, i.e., a figure within the combined experimental uncertainties. The insensitivity of relative entropies to thermal history supports the assumption that the configurational heat capacity of the liquid may be taken as the heat capacity difference between the liquid and the glass (??Cp). Furthermore, this insensitivity allows calculation of the residual entropies at 0 K of diopside glasses as a function of the fictive temperature from the entropy of fusion of diopside and the heat capacities of the crystalline, glassy and liquid phases. For a glass with a fictive temperature of 1005 K, for example, this calorimetric residual entropy is 24.3 ?? 3 J/mol K, in agreement with the prediction made by RICHET (1984) from an analysis of the viscosity data with the configurational-entropy theory of relaxation processes of Adam and Gibbs (1965). In turn, all the viscosity measurements for liquid diopside, which span the range 0.5-4?? 1013 poise, can be quantitatively reproduced through this theory with the calorimetrically determined entropies and ??Cp data. Finally, the unclear significance of "activation energies" for structural interpretations of viscosity data is emphasized, and the importance of ??Cp and glass-transition temperature systematics for determining the composition and temperature dependences of the viscosity is pointed out. ?? 1986.

Richet, P.; Robie, R.A.; Hemingway, B.S.

1986-01-01

258

Fourth Symposium on Macrocyclic Compounds.  

National Technical Information Service (NTIS)

Both theoretical and experimental aspects of the properties and behavior of synthetic and naturally occurring macrocyclic compounds are covered in this symposium. This document contains abstracts of the papers. (ERA citation 06:017177)

J. J. Christensen, R. M. Izatt

1980-01-01

259

Polishing compound for plastic surfaces  

DOEpatents

This invention is comprised of a polishing compound for plastic materials. The compound includes approximately by approximately by weight 25 to 80 parts at least one petroleum distillate lubricant, 1 to 12 parts mineral spirits, 50 to 155 parts abrasive paste, and 15 to 60 parts water. Preferably, the compound includes approximately 37 to 42 parts at least one petroleum distillate lubricant, up to 8 parts mineral spirits, 95 to 110 parts abrasive paste, and 50 to 55 parts water. The proportions of the ingredients are varied in accordance with the particular application. The compound is used on PLEXIGLAS{trademark}, LEXAN{trademark}, LUCITE{trademark}, polyvinyl chloride (PVC), and similar plastic materials whenever a smooth, clear polished surface is desired.

Stowell, M.S.

1991-01-01

260

The Magic of Compound Interest  

NSDL National Science Digital Library

The most powerful force in the universe is compound interest - Albert Einstein - Compound interest is the underlying concept that allows your money to grow on its own and that\\'s what leads to a lucrative future. It\\'s the interest you earn off of your original investment plus the interest you\\'ve already accrued. It\\'s interest on interest. And what it can do is amazing. Compound interest\\'s a cyclical monster that feeds itself and keeps growing at an exponential rate. And the best part about compound interest is that young people have the advantage. Young, first-time investors have an upper hand on older, wiser, Wall Street investors and stock market gurus because young people have ...

Gordon, Mr.

2006-10-19

261

RECOIL LABELING OF ORGANIC COMPOUNDS  

Microsoft Academic Search

The results of C¹⁴-labeling under neutron irradiation of two ; groups of compounds are reported: (1) naphthalene, phenanthrene, and anthracene ; in an attempt to determine whether or not high energy C¹⁴ fragments formed ; by nuclear recoil would favor or discriminate against any particular position in ; product formations; (2) pseudoephedrine, 2-amino-pyrimidine, and 3,6-; dihydroxypyridazine as complex nitrogen-containing compounds.

S. Oae; M. Hamada; Y. Otsuji; N. Furukawa; E. Iwamoto

1963-01-01

262

Sensing acetylcholine and anticholinesterase compounds.  

PubMed

Acetylcholine is a key neurotransmitter, and anticholinesterase agents are essential compounds used as medical drugs, pesticides, and chemical warfare agents. A semisynthetic fluorescence-based probe for the direct, real-time detection of acetylcholine and anticholinesterase compounds is introduced. The probe possesses good sensitivity, tunable detection range, and can be selectively targeted to cell surfaces, thereby making it an attractive tool for applications in analytical chemistry and quantitative biology. PMID:24339043

Schena, Alberto; Johnsson, Kai

2014-01-27

263

Cytotoxic Compounds from Brucea mollis  

PubMed Central

Ten compounds, including soulameanone (1), isobruceine B (2), 9-methoxy-canthin-6-one (3), bruceolline F (4), niloticine (5), octatriacontan-1-ol (6), bombiprenone (7), ?-tocopherol (8), inosine (9), and apigenin 7-O-?-D-glucopyranoside (10), were isolated from the leaves, stems, and roots of Brucea mollis Wall. ex Kurz. Their structures were determined using one-and two-dimensional NMR spectroscopy and mass spectrometry. All compounds were evaluated for their cytotoxic activity against KB (human carcinoma of the mouth), LU-1 (human lung adenocarcinoma), LNCaP (human prostate adeno-carcinoma), and HL-60 (human promyelocytic leukemia) cancer cell lines. Compound 2 showed significant cytotoxic activity against KB, LU-1, LNCaP, and HL-60 cancer cells with IC50 values of 0.39, 0.40, 0.34, and 0.23 ?g/mL, respectively. In addition, compounds 3 and 5 showed significant cytotoxic activity against KB, LU-1, LNCaP, and HL-60 cancer cells with IC50 values around 1–4 ?g/mL. Compounds 9-methoxycanthin-6-one (3) and niloticine (5) have been discovered for the first time from the Brucea genus. PMID:24106661

Tung, Mai Hung Thanh; ?uc, Ho Viet; Huong, Tran Thu; Duong, Nguyen Thanh; Phuong, Do Thi; Thao, Do Thi; Tai, Bui Huu; Kim, Young Ho; Bach, Tran The; Cuong, Nguyen Manh

2013-01-01

264

Extraterrestrial Organic Compounds in Meteorites  

NASA Technical Reports Server (NTRS)

Many organic compounds or their precursors found in meteorites originated in the interstellar or circumstellar medium and were later incorporated into planetesimals during the formation of the solar system. There they either survived intact or underwent further processing to synthesize secondary products on the meteorite parent body. The most distinct feature of CI and CM carbonaceous chondrites, two types of stony meteorites, is their high carbon content (up to 3% of weight), either in the form of carbonates or of organic compounds. The bulk of the organic carbon consists of an insoluble macromolecular material with a complex structure. Also present is a soluble organic fraction, which has been analyzed by several separation and analytical procedures. Low detection limits can be achieved by derivatization of the organic molecules with reagents that allow for analysis by gas chromatography/mass spectroscopy and high performance liquid chromatography. The CM meteorite Murchison has been found to contain more than 70 extraterrestrial amino acids and several other classes of compounds including carboxylic acids, hydroxy carboxylic acids, sulphonic and phosphonic acids, aliphatic, aromatic and polar hydrocarbons, fullerenes, heterocycles as well as carbonyl compounds, alcohols, amines and amides. The organic matter was found to be enriched in deuterium, and distinct organic compounds show isotopic enrichments of carbon and nitrogen relative to terrestrial matter.

Botta, Oliver; Bada, Jeffrey L.; Meyer, Michael (Technical Monitor)

2003-01-01

265

Antitumor Compounds from Marine Actinomycetes  

PubMed Central

Chemotherapy is one of the main treatments used to combat cancer. A great number of antitumor compounds are natural products or their derivatives, mainly produced by microorganisms. In particular, actinomycetes are the producers of a large number of natural products with different biological activities, including antitumor properties. These antitumor compounds belong to several structural classes such as anthracyclines, enediynes, indolocarbazoles, isoprenoides, macrolides, non-ribosomal peptides and others, and they exert antitumor activity by inducing apoptosis through DNA cleavage mediated by topoisomerase I or II inhibition, mitochondria permeabilization, inhibition of key enzymes involved in signal transduction like proteases, or cellular metabolism and in some cases by inhibiting tumor-induced angiogenesis. Marine organisms have attracted special attention in the last years for their ability to produce interesting pharmacological lead compounds. PMID:19597582

Olano, Carlos; Mendez, Carmen; Salas, Jose A.

2009-01-01

266

Gallium-containing anticancer compounds  

PubMed Central

There is an ever pressing need to develop new drugs for the treatment of cancer. Gallium nitrate, a group IIIa metal salt, inhibits the proliferation of tumor cells in vitro and in vivo and has shown activity against non-Hodgkin’s lymphoma and bladder cancer in clinical trials. Gallium can function as an iron mimetic and perturb iron-dependent proliferation and other iron-related processes in tumor cells. Gallium nitrate lacks cross resistance with conventional chemotherapeutic drugs and is not myelosuppressive; it can be used when other drugs have failed or when the blood count is low. Given the therapeutic potential of gallium, newer generations of gallium compounds are now in various phases of preclinical and clinical development. These compounds hold the promise of greater anti-tumor activity against a broader spectrum of cancers. The development of gallium compounds for cancer treatment and their mechanisms of action will be discussed. PMID:22800370

Chitambar, Christopher R

2013-01-01

267

Hydrophobic Compounds Reshape Membrane Domains  

PubMed Central

Cell membranes have a complex lateral organization featuring domains with distinct composition, also known as rafts, which play an essential role in cellular processes such as signal transduction and protein trafficking. In vivo, perturbations of membrane domains (e.g., by drugs or lipophilic compounds) have major effects on the activity of raft-associated proteins and on signaling pathways, but they are difficult to characterize because of the small size of the domains, typically below optical resolution. Model membranes, instead, can show macroscopic phase separation between liquid-ordered and liquid-disordered domains, and they are often used to investigate the driving forces of membrane lateral organization. Studies in model membranes have shown that some lipophilic compounds perturb membrane domains, but it is not clear which chemical and physical properties determine domain perturbation. The mechanisms of domain stabilization and destabilization are also unknown. Here we describe the effect of six simple hydrophobic compounds on the lateral organization of phase-separated model membranes consisting of saturated and unsaturated phospholipids and cholesterol. Using molecular simulations, we identify two groups of molecules with distinct behavior: aliphatic compounds promote lipid mixing by distributing at the interface between liquid-ordered and liquid-disordered domains; aromatic compounds, instead, stabilize phase separation by partitioning into liquid-disordered domains and excluding cholesterol from the disordered domains. We predict that relatively small concentrations of hydrophobic species can have a broad impact on domain stability in model systems, which suggests possible mechanisms of action for hydrophobic compounds in vivo. PMID:25299598

Barnoud, Jonathan; Rossi, Giulia; Marrink, Siewert J.; Monticelli, Luca

2014-01-01

268

Hydrophobic compounds reshape membrane domains.  

PubMed

Cell membranes have a complex lateral organization featuring domains with distinct composition, also known as rafts, which play an essential role in cellular processes such as signal transduction and protein trafficking. In vivo, perturbations of membrane domains (e.g., by drugs or lipophilic compounds) have major effects on the activity of raft-associated proteins and on signaling pathways, but they are difficult to characterize because of the small size of the domains, typically below optical resolution. Model membranes, instead, can show macroscopic phase separation between liquid-ordered and liquid-disordered domains, and they are often used to investigate the driving forces of membrane lateral organization. Studies in model membranes have shown that some lipophilic compounds perturb membrane domains, but it is not clear which chemical and physical properties determine domain perturbation. The mechanisms of domain stabilization and destabilization are also unknown. Here we describe the effect of six simple hydrophobic compounds on the lateral organization of phase-separated model membranes consisting of saturated and unsaturated phospholipids and cholesterol. Using molecular simulations, we identify two groups of molecules with distinct behavior: aliphatic compounds promote lipid mixing by distributing at the interface between liquid-ordered and liquid-disordered domains; aromatic compounds, instead, stabilize phase separation by partitioning into liquid-disordered domains and excluding cholesterol from the disordered domains. We predict that relatively small concentrations of hydrophobic species can have a broad impact on domain stability in model systems, which suggests possible mechanisms of action for hydrophobic compounds in vivo. PMID:25299598

Barnoud, Jonathan; Rossi, Giulia; Marrink, Siewert J; Monticelli, Luca

2014-10-01

269

Halogenated compounds from marine algae.  

PubMed

Marine algae produce a cocktail of halogenated metabolites with potential commercial value. Structures exhibited by these compounds go from acyclic entities with a linear chain to complex polycyclic molecules. Their medical and pharmaceutical application has been investigated for a few decades, however other properties, such as antifouling, are not to be discarded. Many compounds were discovered in the last years, although the need for new drugs keeps this field open as many algal species are poorly screened. The ecological role of marine algal halogenated metabolites has somehow been overlooked. This new research field will provide valuable and novel insight into the marine ecosystem dynamics as well as a new approach to comprehending biodiversity. Furthermore, understanding interactions between halogenated compound production by algae and the environment, including anthropogenic or global climate changes, is a challenging target for the coming years. Research of halogenated metabolites has been more focused on macroalgae than on phytoplankton. However, phytoplankton could be a very promising material since it is the base of the marine food chain with quick adaptation to environmental changes, which undoubtedly has consequences on secondary metabolism. This paper reviews recent progress on this field and presents trends on the role of marine algae as producers of halogenated compounds. PMID:20948909

Cabrita, Maria Teresa; Vale, Carlos; Rauter, Amélia Pilar

2010-01-01

270

Thermochemical data of organic compounds  

Microsoft Academic Search

This reference consists of tables of thermochemical data for many organic compounds. The following topics are covered: standard enthalpies of formation derived from experimental data; prediction of standard enthalpies of formation; group interactions; interpretation of group interactions; prediction of unknown values; and future developments.

J. B. Pedley; R. D. Naylor; S. B. Kirby

1986-01-01

271

Fifth Symposium on Macrocyclic Compounds.  

National Technical Information Service (NTIS)

The fifth symposium on macrocyclic compounds was held at Brigham Young University, Provo, Utah, 10-12 August 1981. The objective of the symposium was to provide a forum for the presentation and discussion of research activities in the field of macrocyclic...

J. J. Christensen, R. M. Izatt

1981-01-01

272

Reconstructive compounding for IVUS palpography.  

PubMed

This study proposes a novel algorithm for luminal strain reconstruction from sparse irregularly sampled strain measurements. It is based on the normalized convolution (NC) algorithm. The novel extension comprises the multilevel scheme, which takes into account the variable sampling density of the available strain measurements during the cardiac cycle. The proposed algorithm was applied to restore luminal strain values in intravascular ultrasound (IVUS) palpography. The procedure of reconstructing and averaging the strain values acquired during one cardiac cycle forms a technique, coined as reconstructive compounding. The accuracy of strain reconstruction was initially tested on the luminal strain map, computed from 3 in vivo IVUS pullbacks. The high quality of strain restoration was observed after systematically removing up to 90% of the initial elastographic measurements. The restored distributions accurately reproduced the original strain patterns and the error did not exceed 5%. The experimental validation of the reconstructed compounding technique was performed on 8 in vivo IVUS pullbacks. It demonstrated that the relative decrease in number of invalid strain estimates amounts to 92.05 +/- 6.03% and 99.17 +/- 0.92% for the traditional and reconstructive strain compounding schemes, respectively. In conclusion, implementation of the reconstructive compounding scheme boosts the diagnostic value of IVUS palpography. PMID:20040400

Danilouchkine, Mikhail G; Mastik, Frits; van der Steen, Antonius F W

2009-12-01

273

Cryogenic container compound suspension strap  

NASA Technical Reports Server (NTRS)

A support strap for use in a cryogenic storage vessel for supporting the inner shell from the outer shell with a minimum heat leak is presented. The compound suspension strap is made from a unidirectional fiberglass epoxy composite material with an ultimate tensile strength and fatigue strength which are approximately doubled when the material is cooled to a cryogenic temperature.

Vorreiter, J. W. (inventor)

1980-01-01

274

Cardioactive compounds from Eremophila species  

Microsoft Academic Search

The isolation and identification of two cardioactive compounds from two Eremophila species (Myoporaceae) considered important in the pharmacopoeia of the Australian Aboriginal people is described. Verbascoside, isolated from the methanol and water extracts of E. alternifolia leaves, mediated significant increases in chronotropism, inotropism and coronary perfusion rate (CPR) in the Langendorff rat heart. Geniposidic acid, isolated from the methanol extract

Marcello Pennacchio; Yana M. Syah; Emilio L. Ghisalberti; Elizabeth Alexander

1996-01-01

275

Microbial degradation of halogenated compounds  

Microsoft Academic Search

The mode of degradation of various halogenated compounds in isolated pure cultures and the disposition of the degradative genes have been studied. In many cases the degradative genes are found to be clustered on plasmids and appear to be under positive control. Genetic selection in vivo and genetic manipulations in vitro have allowed construction of strains having wider biodegradative potentials

D. Ghosal; I.-S. You; D. K. Chatterjee; A. M. Chakrabarty

1985-01-01

276

Coordination compounds in medicinal chemistry  

Microsoft Academic Search

In medicinal chemistry metal complexes as pharmaceuticals have received limited attention compared with organic compounds. Much of the attention has been given to Pt(II) complexes that inhibit tumor growth, but a widely applicable target for development of metal complexes as pharmaceuticals has emerged from new perspectives of enzymes in disease processes. In this review we look at work involving the

Chad W. Schwietert; John P. McCue

1999-01-01

277

Large Constituent Families Help Children Parse Compounds  

ERIC Educational Resources Information Center

The family size of the constituents of compound words, or the number of compounds sharing the constituents, has been shown to affect adults' access to compound words in the mental lexicon. The present study was designed to see if family size would affect children's segmentation of compounds. Twenty-five English-speaking children between 3;7 and…

Krott, Andrea; Nicoladis, Elena

2005-01-01

278

Inorganic lead compounds in electroceramics and glasses  

SciTech Connect

Lead-based compounds are numerous. When the toxicological effects of lead compounds are studied, a distinction between organic and inorganic lead compounds appears because each group behaves differently in biological systems. Examination of inorganic lead compounds exposes additional differences in their stability, modes of human exposure and socioeconomic importance. Lead-based electroceramics and glasses include inorganic lead compounds that can be controlled in the future when restrictions on lead use are enacted. The compounds widely used in electronics pose minimal health risks because of their stability. The socioeconomic impact of restricting these compounds could be significant because of their widespread use and the difficulty of locating replacement materials.

Nair, N.; Bhalla, A.; Roy, R. [Pennsylvania State Univ., University Park, PA (United States)

1996-01-01

279

The nature of compounds: a psychocentric perspective.  

PubMed

Although compound words often seem to be words that themselves contain words, this paper argues that this is not the case for the vast majority of lexicalized compounds. Rather, it is claimed that as a result of acts of lexical processing, the constituents of compound words develop into new lexical representations. These representations are bound to specific morphological roles and positions (e.g., head, modifier) within a compound word. The development of these positionally bound compound constituents creates a rich network of lexical knowledge that facilitates compound processing and also creates some of the well-documented patterns in the psycholinguistic and neurolinguistic study of compounding. PMID:24580553

Libben, Gary

2014-01-01

280

Planck 2013 results. XVI. Cosmological parameters  

NASA Astrophysics Data System (ADS)

This paper presents the first cosmological results based on Planck measurements of the cosmic microwave background (CMB) temperature and lensing-potential power spectra. We find that the Planck spectra at high multipoles (? ? 40) are extremely well described by the standard spatially-flat six-parameter ?CDM cosmology with a power-law spectrum of adiabatic scalar perturbations. Within the context of this cosmology, the Planck data determine the cosmological parameters to high precision: the angular size of the sound horizon at recombination, the physical densities of baryons and cold dark matter, and the scalar spectral index are estimated to be ?? = (1.04147 ± 0.00062) × 10-2, ?bh2 = 0.02205 ± 0.00028, ?ch2 = 0.1199 ± 0.0027, and ns = 0.9603 ± 0.0073, respectively(note that in this abstract we quote 68% errors on measured parameters and 95% upper limits on other parameters). For this cosmology, we find a low value of the Hubble constant, H0 = (67.3 ± 1.2) km s-1 Mpc-1, and a high value of the matter density parameter, ?m = 0.315 ± 0.017. These values are in tension with recent direct measurements of H0 and the magnitude-redshift relation for Type Ia supernovae, but are in excellent agreement with geometrical constraints from baryon acoustic oscillation (BAO) surveys. Including curvature, we find that the Universe is consistent with spatial flatness to percent level precision using Planck CMB data alone. We use high-resolution CMB data together with Planck to provide greater control on extragalactic foreground components in an investigation of extensions to the six-parameter ?CDM model. We present selected results from a large grid of cosmological models, using a range of additional astrophysical data sets in addition to Planck and high-resolution CMB data. None of these models are favoured over the standard six-parameter ?CDM cosmology. The deviation of the scalar spectral index from unity isinsensitive to the addition of tensor modes and to changes in the matter content of the Universe. We find an upper limit of r0.002< 0.11 on the tensor-to-scalar ratio. There is no evidence for additional neutrino-like relativistic particles beyond the three families of neutrinos in the standard model. Using BAO and CMB data, we find Neff = 3.30 ± 0.27 for the effective number of relativistic degrees of freedom, and an upper limit of 0.23 eV for the sum of neutrino masses. Our results are in excellent agreement with big bang nucleosynthesis and the standard value of Neff = 3.046. We find no evidence for dynamical dark energy; using BAO and CMB data, the dark energy equation of state parameter is constrained to be w = -1.13-0.10+0.13. We also use the Planck data to set limits on a possible variation of the fine-structure constant, dark matter annihilation and primordial magnetic fields. Despite the success of the six-parameter ?CDM model in describing the Planck data at high multipoles, we note that this cosmology does not provide a good fit to the temperature power spectrum at low multipoles. The unusual shape of the spectrum in the multipole range 20 ? ? ? 40 was seen previously in the WMAP data and is a real feature of the primordial CMB anisotropies. The poor fit to the spectrum at low multipoles is not of decisive significance, but is an "anomaly" in an otherwise self-consistent analysis of the Planck temperature data.

Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartlett, J. G.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bobin, J.; Bock, J. J.; Bonaldi, A.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Bridges, M.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cappellini, B.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chary, R.-R.; Chen, X.; Chiang, H. C.; Chiang, L.-Y.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Dickinson, C.; Diego, J. M.; Dolag, K.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Dunkley, J.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Gaier, T. C.; Galeotta, S.; Galli, S.; Ganga, K.; Giard, M.; Giardino, G.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Haissinski, J.; Hamann, J.; Hansen, F. K.; Hanson, D.; Harrison, D.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hou, Z.; Hovest, W.; Huffenberger, K. M.; Jaffe, A. H.; Jaffe, T. R.; Jewell, J.; Jones, W. C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Laureijs, R. J.; Lawrence, C. R.; Leach, S.; Leahy, J. P.; Leonardi, R.; León-Tavares, J.; Lesgourgues, J.; Lewis, A.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maffei, B.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martin, P. G.; Martínez-González, E.; Masi, S.; Massardi, M.; Matarrese, S.; Matthai, F.; Mazzotta, P.; Meinhold, P. R.; Melchiorri, A.; Melin, J.-B.; Mendes, L.; Menegoni, E.; Mennella, A.; Migliaccio, M.; Millea, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; O'Dwyer, I. J.; Osborne, S.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paladini, R.; Paoletti, D.; Partridge, B.; Pasian, F.; Patanchon, G.; Pearson, D.; Pearson, T. J.; Peiris, H. V.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Platania, P.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Poutanen, T.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Scott, D.; Seiffert, M. D.; Shellard, E. P. S.; Spencer, L. D.; Starck, J.-L.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sureau, F.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Tavagnacco, D.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Türler, M.; Umana, G.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L. A.; Wandelt, B. D.; Wehus, I. K.; White, M.; White, S. D. M.; Wilkinson, A.; Yvon, D.; Zacchei, A.; Zonca, A.

2014-11-01

281

Amperometry with two polarizable electrodes. XVI  

Microsoft Academic Search

Conditions for the magnesium determination in alkaline solution by EDTA titration with biamperometric indication were examined. The most preferable pH range was found to be above 9.6. A reliable determination can be carried out in the presence of Ca, Ni, Cu and Co up to the ratio of 1:1. In the case of higher concentrations of Cu and Ni masking

Jan Vorlí?ek; Milan Fara; František Vydra

1968-01-01

282

Thin compound-eye camera.  

PubMed

An artificial compound-eye objective fabricated by micro-optics technology is adapted and attached to a CMOS sensor array. The novel optical sensor system with an optics thickness of only 0.2 mm is examined with respect to resolution and sensitivity. An optical resolution of 60 x 60 pixels is determined from captured images. The scaling behavior of artificial compound-eye imaging systems is analyzed. Cross talk between channels fabricated by different technologies is evaluated, and the influence on an extension of the field of view by addition of a (Fresnel) diverging lens is discussed. The lithographic generation of opaque walls between channels for optical isolation is experimentally demonstrated. PMID:15929282

Duparré, Jacques; Dannberg, Peter; Schreiber, Peter; Bräuer, Andreas; Tünnermann, Andreas

2005-05-20

283

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

Smith, L.A. Jr.

1989-07-18

284

[Perfluorinated compounds in potable water].  

PubMed

In a pilot study perfluorinated compounds such as perfluorobutane sulfonate (PFBS), perfluorohexane suflonate (PFHS), perfluorooctane sulfonate (PFOS), perfluorooctane sulfonamide (PFOSA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorotetradecanoic acid (PFTeDA), perfluorohexadecanoic acid (PFHxDA) and perfluorooctadecanoic acid (PFOcDA) have been determined in the Japanese and Polish brands of bottled mineral water and in tap water. Bottled mineral water from both countries contained ultratrace amounts of some perfluorinated compounds, and higher degree of contamination showed tap water. PFOS and PFOA concentrations were much below threshold level for toxic effects, and Hazard Quotient (HQ) was much < 1. PMID:19143425

Rostkowski, Pawe?; Taniyasu, Sachi; Yamashita, Nobuyoshi; Falandysz, Jerzy

2008-01-01

285

Percutaneous absorption of uranium compounds.  

PubMed

Percutaneous absorption of soluble and insoluble uranium compounds has been induced in order to obtain information on penetration routes and the tissue injury produced by uranium salts. The high electron density of uranium provided a reliable way to visualize, by electron microscopy, the precise localization of the heavy compounds within the tissues. Few minutes after topical application of uranyl nitrate, dense deposits of uranium were observed at the epidermal barrier level. A few hours later, dense deposits were seen filling the intercellular spaces and were also scattered in the cytoplasm and nucleus. Mortality and body weight measurements indicated the high toxicity of uranyl nitrate and ammonium uranyl tricarbonate; uranyl acetate and ammonium diuranate were less toxic. As no penetration was achieved after uranium dioxide, no variations were detected on these parameters. PMID:6832127

de Rey, B M; Lanfranchi, H E; Cabrini, R L

1983-04-01

286

Bacterial Degradation of Aromatic Compounds  

PubMed Central

Aromatic compounds are among the most prevalent and persistent pollutants in the environment. Petroleum-contaminated soil and sediment commonly contain a mixture of polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatics. Aromatics derived from industrial activities often have functional groups such as alkyls, halogens and nitro groups. Biodegradation is a major mechanism of removal of organic pollutants from a contaminated site. This review focuses on bacterial degradation pathways of selected aromatic compounds. Catabolic pathways of naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene are described in detail. Bacterial catabolism of the heterocycles dibenzofuran, carbazole, dibenzothiophene, and dibenzodioxin is discussed. Bacterial catabolism of alkylated PAHs is summarized, followed by a brief discussion of proteomics and metabolomics as powerful tools for elucidation of biodegradation mechanisms. PMID:19440284

Seo, Jong-Su; Keum, Young-Soo; Li, Qing X.

2009-01-01

287

Intersections of an interval by a difference of a compound Poisson process and a compound renewal  

E-print Network

Intersections of an interval by a difference of a compound Poisson process and a compound renewal of a compound Poisson process and a compound renewal process. The results obtained are applied for a particular case of this process, namely, for the difference of the compound Poisson process and the renewal

Einmahl, Uwe

288

Association Norms of German Noun Compounds Overview: Noun Compounds, Compositionality, and Associations  

E-print Network

Association Norms of German Noun Compounds Overview: Noun Compounds, Compositionality, and Associations German Noun Compounds · Compounds: combinations of two or more simplex words; examples for German, depictable noun compounds from von der Heide and Borgwaldt (2009) Compositionality · Interest: degrees

Reyle, Uwe

289

Synthesis of Fluorinated ZDDP Compounds  

Microsoft Academic Search

Volatile degradation products of zinc dialkyl dithio phosphate (ZDDP) composed of phosphorus and sulfur compounds reduce the\\u000a efficiency of catalytic converters resulting in harmful emissions. A unique way of reducing ZDDP level while maintaining good\\u000a antiwear performance has been achieved by reacting a novel additive FeF3 with ZDDP. The objective of this research is to examine the chemical interactions between

Kajal Parekh; Xin Chen; Pranesh B. Aswath

2009-01-01

290

Compound facial expressions of emotion  

PubMed Central

Understanding the different categories of facial expressions of emotion regularly used by us is essential to gain insights into human cognition and affect as well as for the design of computational models and perceptual interfaces. Past research on facial expressions of emotion has focused on the study of six basic categories—happiness, surprise, anger, sadness, fear, and disgust. However, many more facial expressions of emotion exist and are used regularly by humans. This paper describes an important group of expressions, which we call compound emotion categories. Compound emotions are those that can be constructed by combining basic component categories to create new ones. For instance, happily surprised and angrily surprised are two distinct compound emotion categories. The present work defines 21 distinct emotion categories. Sample images of their facial expressions were collected from 230 human subjects. A Facial Action Coding System analysis shows the production of these 21 categories is different but consistent with the subordinate categories they represent (e.g., a happily surprised expression combines muscle movements observed in happiness and surprised). We show that these differences are sufficient to distinguish between the 21 defined categories. We then use a computational model of face perception to demonstrate that most of these categories are also visually discriminable from one another. PMID:24706770

Du, Shichuan; Tao, Yong; Martinez, Aleix M.

2014-01-01

291

Biofiltration of volatile organic compounds.  

PubMed

The removal of volatile organic compounds (VOCs) from contaminated airstreams has become a major air pollution concern. Improvement of the biofiltration process commonly used for the removal of odorous compounds has led to a better control of key parameters, enabling the application of biofiltration to be extended also to the removal of VOCs. Moreover, biofiltration, which is based on the ability of micro-organisms to degrade a large variety of compounds, proves to be economical and environmentally viable. In a biofilter, the waste gas is forced to rise through a layer of packed porous material. Thus, pollutants contained in the gaseous effluent are oxidised or converted into biomass by the action of microorganisms previously fixed on the packing material. The biofiltration process is then based on two principal phenomena: (1) transfer of contaminants from the air to the water phase or support medium, (2) bioconversion of pollutants to biomass, metabolic end-products, or carbon dioxide and water. The diversity of biofiltration mechanisms and their interaction with the microflora mean that the biofilter is defined as a complex and structured ecosystem. As a result, in addition to operating conditions, research into the microbial ecology of biofilters is required in order better to optimise the management of such biological treatment systems. PMID:15803311

Malhautier, Luc; Khammar, Nadia; Bayle, Sandrine; Fanlo, Jean-Louis

2005-07-01

292

Characterization of volatile compounds in Astraeus spp.  

PubMed

Astraeus spp. is consumed in several regions of Southeast Asia. C(8) compounds, including 1-octen-3-ol, are the main volatile compounds in fresh Astraeus spp. Other compounds typical of edible mushrooms, such as terpenoids and sulfur-containing compounds, were not detected in fresh Astraeus spp. The amounts of fatty acids, including linoleic acid, substantially decreased after homogenization of fresh Astraeus spp. This high metabolic activity possibly correlates with formation of the C(8) volatiles. Heating the mushrooms produced cyclohexene compounds, 2-n-pentyl-furan, furanyl compounds, and benzaldehyde. PMID:19966456

Kakumyan, Pattana; Matsui, Kenji

2009-12-01

293

Physical properties of glycosyl diacylglycerols. 1. Calorimetric studies of a homologous series of 1,2-di-O-acyl-3-O-(alpha-D-glucopyranosyl)-sn-glycerols.  

PubMed

The polymorphic phase behavior of aqueous dispersions of a homologous series of 1,2-di-O-acyl-3-O-(alpha-D-glucopyranosyl)-sn-glycerols was studied by differential scanning calorimetry. At fast heating rates unannealed samples of these lipids exhibit a strongly energetic transition, which has been identified as a lamellar gel/liquid crystalline (L beta/L alpha) phase transition (short- and medium-chain compounds) or a lamellar gel to inverted hexagonal (L beta/HII) phase transition (long-chain compounds) by X-ray diffraction studies (Sen et al., 1990). At still higher temperatures, some of the lipids that form lamellar liquid-crystalline phases exhibit an additional transition, which has been identified as a transition to an inverted nonbilayer phase by X-ray diffraction studies. The lamellar gel phase formed on initial cooling of these lipids is a metastable structure, which, when annealed under appropriate conditions, transforms to a more stable lamellar gel phase, which has been identified as a poorly hydrated crystal-like phase with tilted acyl chains by X-ray diffraction measurements (Sen et al., 1990). With the exception of the di-19:0 homologue, the crystalline phases of these lipids are stable to temperatures higher than those at which their L beta phases melt and, as a result, they convert directly to L alpha or HII phases on heating. Our results indicate that the length of the acyl chain affects both the kinetic and thermodynamic properties of the crystalline phases of these lipids as well as the type of nonbilayer phase that they form. Moreover, when compared with the beta-anomers, these alpha-D-glucosyl diacylglycerols are more prone to form ordered crystalline gel phases at low temperatures and are somewhat less prone to form nonbilayer phases at elevated temperatures. Thus the physical properties of glucolipids (and possibly all glycolipids) are very sensitive to the nature of the anomeric linkage between the sugar headgroup and the glycerol backbone of the lipid molecule. We suggest that this is, in part, due to a change in orientation of the glucopyranosyl ring relative to the bilayer surface, which in turn affects the way(s) in which the sugar headgroups interact with each other and with water. PMID:2261435

Mannock, D A; Lewis, R N; McElhaney, R N

1990-08-28

294

Sibling and Independent Compound Chondrules  

NASA Astrophysics Data System (ADS)

We studied compound chondrules in 79 cm2 of ordinary chondrite (OC) thin sections. Compound chondrules consist of a primary that solidified first and one or more secondaries attached to the primary. Sibling compound chondrules have very similar textures and compositions; most, perhaps all, seem to consist of chondrules melted in the same heating event. About 1.4% of all chondrules are the primaries of sibling compound chondrules. A smaller fraction, 1.0%, of all chondrules are the primaries of independent chondrules, the members of which were melted in separate heating events. Independent chondrules show appreciable differences in texture and/or composition. We propose that sibling chondrules originated when numerous chondrules were created from one large, more-or-less homogeneous, precursor assemblage that was flash-melted to produce a large set (perhaps 100-1000) of chondrules; some of these collided while molten, probably within several centimeters of the production site. We envision that small radial velocities were imparted to the members of the set, with small differences in velocity causing collisions among those few in intersecting trajectories. If all chondrules were produced this way, the collision efficiency was 1.4%; if only 10% were produced in this fashion, the efficiency rises to 14%. The original Gooding-Keil model of independent compound chondrule formation calls for random collisions to occur while the secondaries were molten. This appears improbable because the mean period between collisions in the dusty midplane of the nebula is estimated to be hours (or days), orders of magnitude longer than the period during which chondrules could have retained low viscosities following a flash-heating event in a cool (<700 K) nebula. We suggest that most independent compound chondrules formed by the mechanism that accounts for chondrules with relict grains and for chondrules with coarse- grained rims: the primary chondrule was embedded in a porous dust assemblage at the time of the second heating event; it experienced minimal melting because melting efficiency increases with increasing surface/volume ratio. There is a minor tendency for the FeO/(FeO+MgO) ratio in independent secondaries to be higher than in primaries, as expected if this ratio increased with time in the nebular dust. However, Monte Carlo calculations confirm that the compositions of independent secondaries are not randomly distributed, but related to those of primaries. Some exchange probably occurred during the fusion of the two chondrules, but this mechanism seems unable to account for the general similarity of independent primary/secondary compositions. This suggests that, in the environment where, at any one time, chondrules were forming (perhaps the interface between the gaseous nebula and the dusty midplane), the dust composition was more uniform than it was in the central midplane at a later time when agglomeration occurred.

Wasson, J. T.; Krot, A. N.; Rubin, A. E.

1993-07-01

295

The Chemistry of Highly Fluorinated Compounds  

NSDL National Science Digital Library

The featured molecules for January come from the paper Fluorous Compounds and Their Role in Separation Chemistry by Maria Angeles Ubeda and Roman Dembinski. This paper explores the use of highly fluorinated compounds as solvents, catalysts, and reagents.

296

Polyfluorinated Compounds: Past, Present, and Future  

EPA Science Inventory

Interest and concern about polyfluorinated compounds (PFCs), such as perfluorooctane sulfonate (PFOS), erfluorooctanoic acid (PFOA), and an increasing number of other related compounds is growing as more is learned about these ubiquitous anthropogenic substances. Many of these co...

297

Hyperpolarizable compounds and devices fabricated therefrom  

DOEpatents

Substituted compounds having relatively large molecular first order hyperpolarizabilities are provided, along with devices and materials containing them. In general, the compounds bear electron-donating and electron-withdrawing chemical substituents on a polyheterocyclic core. 13 figs.

Therien, M.J.; DiMagno, S.G.

1998-07-21

298

BBC Bitesize: Compounds and Mixtures  

NSDL National Science Digital Library

This animated tutorial for grades 6-9, published by the British Broadcasting Corporation, explores the molecular basis of compounds and mixtures. It is written in "bite-size" pieces so that adolescent learners can grasp the concepts more easily and connect information with prior knowledge. Each page is supplemented with audio narration and illustrations. Learners will try to fuse or separate elements, giving them insight into the bonding process without introducing advanced vocabulary. They will also view animations of filtration and evaporation. The tutorial ends with a brief quiz that allows students to self-test their understanding.

Bitesize, General C.

2011-06-27

299

Low volatile organic compound paints  

SciTech Connect

Increasingly stringent air emission standards in various states has dictated the elimination of engineering finishes which are derived from high volatile organic compound (VOC) paint chemistries. In July 1989, Allied-Signal, Inc., Kansas City Division, Kansas City, Missouri, voluntarily closed its paint facility, due to non-compliance with local air emission standards. The following details the materials selection and evaluations which led to current processing using low VOC paints, which permitted the Allied Signal, Inc., paint facility to achieve compliance and resume operations. 1 tab.

Martinez, F.E.

1991-01-01

300

Volatile organic compound sensor system  

DOEpatents

Generally, this invention relates to the development of field monitoring methodology for new substances and sensing chemical warfare agents (CWAs) and terrorist substances. It also relates to a portable test kit which may be utilized to measure concentrations of halogenated volatile organic compounds (VOCs) in the field. Specifically it relates to systems for reliably field sensing the potential presence of such items while also distinguishing them from other elements potentially present. It also relates to overall systems and processes for sensing, reacting, and responding to an indicated presence of such substance, including modifications of existing halogenated sensors and arrayed sensing systems and methods.

Schabron, John F. (Laramie, WY); Rovani, Jr., Joseph F. (Laramie, WY); Bomstad, Theresa M. (Waxahachie, TX); Sorini-Wong, Susan S. (Laramie, WY); Wong, Gregory K. (Laramie, WY)

2011-03-01

301

Pharmaceutical Compounds Studied Using NEXAFS  

NASA Astrophysics Data System (ADS)

Total Electron Yield (TEY) oxygen K-edge NEXAFS detects the presence of strongly adsorbed water molecules on poloxamer-coated pharmaceutical actives, which provides a useful spectroscopic indicator for bioavailability. The results are supported by complementary XPS measurements. Carbon K-edge spectra obtained in a high-pressure NEXAFS cell were used in situ to establish how a polymer coating spread on a drug surface by using humidity induced dispersion of the coating. Finally, we demonstrate how combined Carbon and Oxygen K-edge measurements can be used to characterize amorphous surface layers on micronised crystals of a drug compound.

Murray Booth, A.; Braun, Simon; Lonsbourough, Tom; Purton, John; Patel, Sunil; Schroeder, Sven L. M.

2007-02-01

302

Valence-bond isomers of aromatic compounds  

Microsoft Academic Search

After a brief survey of the history of valence-bond isomers of aromatic compounds, new syntheses and the reactions of these isomers reported in the last decade are reviewed. In the second chapter, the valence-bond isomers of homoaromatic compounds, especially benzene derivatives, are described and in the third chapter those of heterocyclic compounds. Photoreactions of perfluoroalkylated aromatic compounds afford valence-bond isomers

Yoshiro Kobayashi; Itsumaro Kumadaki

303

Compound Poisson disorder problem Savas Dayanik  

E-print Network

; quickest detection; compound Poisson processes, optimal stopping MSC2000 Subject Classification: Primary) be a probability space hosting a compound Poisson process Xt = X0 + Nt k=1 Yk, t 0. (1) Jumps arrive accordingCompound Poisson disorder problem Savas Dayanik Princeton University, Department of Operations

Dayanik, Savas

304

Biologically active compounds of semi-metals  

Microsoft Academic Search

Semi-metals, viz. boron, silicon, arsenic, selenium, tellurium and astatine form organo-metal compounds, some of which are found in nature and have striking effects on the physiology of living organisms. Representatives of these compounds are, e.g., four boron-containing antibiotics (aplasmomycin, borophycin, boromycin, and tatrolon). Silicon compounds, frequently present in \\

T. ?ezanka; K. Sigler

2008-01-01

305

Antidiabetic and toxic effects of vanadium compounds  

Microsoft Academic Search

Compounds of the trace element vanadium have been shown to mimic insulin in in vitro and in vivo systems. These compounds have been found to exert anti-diabetic effects in rodent models of type 1 and type 2 diabetes mellitus as well as in a limited number of studies in human diabetic subjects. Thus, vanadium compounds have emerged as agents for

Ashok K. Srivastava

2000-01-01

306

Lithium reactions with intermetallic-compound electrodes.  

SciTech Connect

Intermetallic compounds are under investigation as possible anode materials in lithium batteries. The compounds on which the Argonne National Laboratory group has primarily focused were selected on the basis of structural compatibility between host and product (lithiated) phases. In this presentation, we discuss the additional insights into the behavior of intermetallic-compound anodes that are available from materials modeling.

Benedek, R.; Thackeray, M. M.; Chemical Engineering

2002-08-22

307

Thin films of mixed metal compounds  

DOEpatents

A compositionally uniform thin film of a mixed metal compound is formed by simultaneously evaporating a first metal compound and a second metal compound from independent sources. The mean free path between the vapor particles is reduced by a gas and the mixed vapors are deposited uniformly. The invention finds particular utility in forming thin film heterojunction solar cells.

Mickelsen, Reid A. (Bellevue, WA); Chen, Wen S. (Seattle, WA)

1985-01-01

308

Formation of oxygenated compounds from isooctane flames  

Microsoft Academic Search

The formation of three families of oxygenated compounds is studied in the case of isooctane combustion. Stoichiometric, lean and rich conditions are studied at different distances from a flat burner. Nine carbonyl compounds, five alcohols and three organic acids are found in detectable concentrations in the combustion products. These oxygenated compounds are formed very quickly, their concentrations increase or remain

Efthimios Zervas; Stavros Poulopoulos; Constantinos Philippopoulos

2006-01-01

309

Characterizing specialized compounding in community pharmacies  

Microsoft Academic Search

BackgroundCompounding is a traditional role of pharmacists that declined with the availability of manufactured medicines. Compounding is now increasingly offered by community pharmacies as a specialized service, and there are calls for regulatory and practice standard changes. However, the characteristics of specialized compounding are not well understood.

Jennifer Anne Giam; Andrew J. McLachlan; Ines Krass

310

COURSE OUTLINE -PHAR 6222 Advanced Pharmaceutical Compounding  

E-print Network

Director: Gary Carlson, B.A., B.S. Pharm., RPh Office: Fairview Compounding Pharmacy 711 Kasota Ave, MplsCOURSE OUTLINE - PHAR 6222 Advanced Pharmaceutical Compounding 2 Credits, Spring 2013 Course, the student will be able to: 1. Explain methods used to compound most commonly prescribed dosage forms

Thomas, David D.

311

Compound words and structure in the lexicon  

Microsoft Academic Search

The structure of lexical entries and the status of lexical decomposition remain controversial. In the psycholinguistic literature, one aspect of this debate concerns the psychological reality of the morphological complexity difference between compound words (teacup) and single words (crescent). The present study investigates morphological decomposition in compound words using visual lexical decision with simultaneous magnetoencephalography (MEG), comparing compounds, single words,

Robert Fiorentino; David Poeppel

2007-01-01

312

Corrosion Preventive Compounds Lifetime Testing  

NASA Technical Reports Server (NTRS)

Lifetime Testing of Corrosion Preventive Compounds (CPCs) was performed to quantify performance in the various environments to which the Space Shuttle Orbiter is exposed during a flight cycle. Three CPCs are approved for use on the Orbiter: RD Calcium Grease, Dinitrol AV-30, and Braycote 601 EF. These CPCs have been rigorously tested to prove that they mitigate corrosion in typical environments, but little information is available on how they perform in the unique combination of the coastal environment at the launch pad, the vacuum of low-earth orbit, and the extreme heat of reentry. Currently, there is no lifetime or reapplication schedule established for these compounds that is based on this combination of environmental conditions. Aluminum 2024 coupons were coated with the three CPCs and exposed to conditions that simulate the environments to which the Orbiter is exposed. Uncoated Aluminum 2024 coupons were exposed to the environmental conditions as a control. Visual inspection and Electro- Impedance Spectroscopy (EIS) were performed on the samples in order to determine the effectiveness of the CPCs. The samples were processed through five mission life cycles or until the visual inspection revealed the initiation of corrosion and EIS indicated severe degradation of the coating.

Hale, Stephanie M.; Kammerer, Catherine C.; Copp, Tracy L.

2007-01-01

313

Valuable compounds in macroalgae extracts.  

PubMed

Bioactive compounds present in ethanolic extracts from 18 macroalgae of the Portuguese coast were analysed by gas chromatography-mass spectrometry (GC-MS), leading to the characterization of 14 compounds: proline, phloroglucinol, mannitol, 8 fatty acids and 3 sterols. A dose-dependent response against enzymes with biological significance (?-glucosidase, acetylcholinesterase and butyrylcholinesterase) and free radicals (DPPH, nitric oxide, superoxide and hydroxyl) was found, Phaeophyta being the most promising group. A PCA analysis was performed and allowed the establishment of a correlation between the algae chemical composition and the biological activity. Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus are among the most active species, which is in accordance with their higher contents in phloroglucinol, mannitol, oleic, arachidonic and eicosapentaenoic acids, and fucosterol. The results point to the potential interest of the use of Phaeophyta species as food additives, due to their potent antiradical activities, and especially highlights the importance of F. spiralis in the food chain of Mediterranean countries. Moreover, the incorporation of the extracts of these species in food products, nutraceutical and pharmaceutical preparations for human health should also be instigated, since they can suppress hyperglycemia and inhibit cholinesterases. PMID:23411314

Andrade, Paula B; Barbosa, Mariana; Matos, Rui Pedro; Lopes, Graciliana; Vinholes, Juliana; Mouga, Teresa; Valentão, Patrícia

2013-06-01

314

Compound prism design principles, I  

PubMed Central

Prisms have been needlessly neglected as components used in modern optical design. In optical throughput, stray light, flexibility, and in their ability to be used in direct-view geometry, they excel over gratings. Here we show that even their well-known weak dispersion relative to gratings has been overrated by designing doublet and double Amici direct-vision compound prisms that have 14° and 23° of dispersion across the visible spectrum, equivalent to 800 and 1300 lines/mm gratings. By taking advantage of the multiple degrees of freedom available in a compound prism design, we also show prisms whose angular dispersion shows improved linearity in wavelength. In order to achieve these designs, we exploit the well-behaved nature of prism design space to write customized algorithms that optimize directly in the nonlinear design space. Using these algorithms, we showcase a number of prism designs that illustrate a performance and flexibility that goes beyond what has often been considered possible with prisms. PMID:22423145

Hagen, Nathan; Tkaczyk, Tomasz S.

2011-01-01

315

Corrosion Preventive Compounds Lifetime Testing  

NASA Technical Reports Server (NTRS)

Lifetime Testing of Corrosion Preventive Compounds (CPCs) was performed to quantify performance in the various environments to which the Space Shuttle Orbiter is exposed during a flight cycle. Three CPCs are approved for use on the Orbiter: HD Calcium Grease, Dinitrol AV-30, and Braycote 601 EF. These CPCs have been rigorously tested to prove that they mitigate corrosion in typical environments, but little information is available on how they perform in the unique combination of the coastal environment at the launch pad, the vacuum of low-earth orbit, and the extreme heat of reentry. Currently, there is no lifetime or reapplication schedule established for these compounds that is based on this combination of environmental conditions. Aluminum 2024 coupons were coated with the three CPCs and exposed to conditions that simulate the environments to which the Orbiter is exposed. Uncoated Aluminum 2024 coupons were exposed to the environmental conditions as a control. Visual inspection and Electro- Impedance Spectroscopy (EIS) were performed on the samples in order to determine the effectiveness of the CPCs. The samples were processed through five mission life cycles or until the visual inspection revealed the initiation of corrosion and EIS indicated severe degradation of the coating.

Hale, Stephanie M.; Kammerer, Catherine C.

2007-01-01

316

Prebiotic Evolution of Nitrogen Compounds  

NASA Technical Reports Server (NTRS)

Support from this four year grant has funded our research on two general problems. One involves attempts to model the abiotic formation of simple source compounds for functional biomolecules, their concentration from dilute state in the hydrosphere and, in several cases, surface induced reactions to form precursor monomers for bioactive end products (refs. 1-5). Because of the pervasiveness and antiquity of phosphate based biochemistry and the catalytic activity of RNA we have exploring the hypothesis of an RNA World as an early stage in the emergence of life. This concept is now rather generally considered, but has been questioned due to the earlier lack of an experimentally demonstrated successful scheme for the spontaneous formation of ribose phosphate, the key backbone molecule in RNA. That impediment has now been removed. This has been achieved by demonstrating probable sources of activated (condensed) highly soluble and strongly sorbed phosphates in nature (Refs. 1,2) and effective condensation of aldehyde phosphates to form ribose phosphate in high yield (ref.6), thereby placing the RNA World concept on a somewhat safer experimental footing. Like all work in this field these experiments are oversimplifications that largely ignore competing side reactions with other compounds expected to be present. None the less our choice of experimental conditions aim at selective processes that eliminate interfering reactions. We have also sought to narrow the credibility gap by simulating geophysically and geochemically plausible conditions surrounding the putative prebiotic reactions.

Arrhenius, G.

1999-01-01

317

Optical detection of alkali compounds  

SciTech Connect

Experiments to evaluate the photofragment fluorescence diagnostic technique for NaCl, KCl, and NaOH in terms of discrimination potential, sensitivity, and quantitative behavior have been completed. All results so far make this technique look very promising for potential applications in post-combustion coal gas streams. Based on the success of the investigations to date, we are continuing to expand the application of the photofragment technique to other gas-phase alkali compounds of importance in fossil fuel combustion. In particular, work is now in progress to investigate potassium hydroxide, KOH. Ongoing experiments are to determine (1) the optimum wavelength for K* production, (2) whether KOH can be measured in the presence of KCl, (3) if the signals linearly track the KOH monomer density, and (4) the absolute sensitivity of the technique for KOH in high-temperature environments.

Oldenborg, R.C.; Baughcum, S.L.

1986-01-01

318

Organic compounds in carbonaceous meteorites.  

PubMed

The carbonaceous chondrite meteorites are fragments of asteroids that have remained relatively unprocessed since the formation of the solar system 4.6 billion years ago. These carbon-rich objects contain a variety of extraterrestrial organic molecules that constitute a record of chemical evolution prior to the origin of life. Compound classes include aliphatic hydrocarbons, aromatic hydrocarbons, amino acids, carboxylic acids, sulfonic acids, phosphonic acids, alcohols, aldehydes, ketones, sugars, amines, amides, nitrogen heterocycles, sulfur heterocycles and a relatively abundant high molecular weight macromolecular material. Structural and stable isotopic characteristics suggest that a number of environments may have contributed to the organic inventory, including interstellar space, the solar nebula and the asteroidal meteorite parent body. This review covers work published between 1950 and the present day and cites 193 references. PMID:12137279

Sephton, Mark A

2002-06-01

319

Volatile organic compound sensing devices  

DOEpatents

Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs. 15 figs.

Lancaster, G.D.; Moore, G.A.; Stone, M.L.; Reagen, W.K.

1995-08-29

320

Volatile organic compound sensing devices  

DOEpatents

Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs.

Lancaster, Gregory D. (Idaho Falls, ID); Moore, Glenn A. (Idaho Falls, ID); Stone, Mark L. (Idaho Falls, ID); Reagen, William K. (Stillwater, MN)

1995-01-01

321

Phenolic compounds from Nymphaea odorata.  

PubMed

Assay-guided fractionation of the ethanol extract of Nymphaea odorata resulted in the identification of two lignans, one new (1) and one known (2), together with six known flavonol glycosides (3-8). The structures of 1-8 were established by spectroscopic analysis as nymphaeoside A (1), icariside E(4) (2), kaempferol 3-O-alpha-l-rhamnopyranoside (afzelin, 3), quercetin 3-O-alpha-l-rhamnopyranoside (4), myricetin 3-O-alpha-l-rhamnopyranoside (myricitrin, 5), quercetin 3-O-(6' '-O-acetyl)-beta-d-galactopyranoside (6), myricetin 3-O-beta-d-galactopyranoside (7), and myricetin 3-O-(6' '-O-acetyl)-beta-d-galactopyranoside (8). Compounds 3, 4, and 7 showed marginal inhibitory effect against fatty acid synthase with IC(50) values of 45, 50, and 25 microg/mL, respectively. PMID:12713413

Zhang, Zhizhen; ElSohly, Hala N; Li, Xing-Cong; Khan, Shabana I; Broedel, Sheldon E; Raulli, Robert E; Cihlar, Ronald L; Burandt, Charles; Walker, Larry A

2003-04-01

322

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70 C and 500 C and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

1993-01-05

323

Control of insects and spider mites by translocated compounds  

E-print Network

. Fourteen compounds were found to have systemic properties. These were: Compound 3885, S-mercaptoacetylurea 0,0-diethyldithiophosphate Compound 3901, S-mercaptoacetylurea 0,0-dimethyl dithiophosphate Compound 3741, S-carbamylmethyl 0,0-diethyl... dithiophosphate Compound 3869, S-carbamylmethyl 0,0-dimethyl dithiophosphate Compound 4001, S-oarbanylmethyl 0,0-di-n-propyl dithiophosphate Compound 4116, S-(NN-diethyl) carbamylmethyl 0,0-di-n-propyl dithiophosphate Compound E-1059, (confidential) Compound...

Ivy, Edward Everett

2013-10-04

324

Estimation of the compounding distribution in the compound Poisson process model for earthquakes  

Microsoft Academic Search

Compound Poisson process models have been studied earlier for earthquake occurrences, with some arbitrary compounding distributions.\\u000a It is more meaningful to abstract information about the compounding distribution from the empirical observations on the earthquake\\u000a sequences. The difinition of a compound distribution can be interpreted as an integral transform of the compounding distribution.\\u000a The latter distribution can therefore be estimated by

P S Moharir

1992-01-01

325

Two new mesophases in a chiral compound A. M. Levelut, C. Germain, P. Keller, L. Liebert  

E-print Network

not exhibit a total miscibility range; while for the second the untwisted form observed with the racemic of the racemic mixture is more than Fig. 1. - The molecule of 1 (methyl)-heptyl-terephthalidene- bis successively the optical and calorimetric observations of the pure enantiomer and of the racemic mixture

Boyer, Edmond

326

Calorimetric, spectroscopic and structural investigations of phase polymorphism in [Ru(NH{sub 3}){sub 6}](BF{sub 4}){sub 3}. Part I  

SciTech Connect

Four crystalline phases of the coordination compound [Ru(NH{sub 3}){sub 6}](BF{sub 4}){sub 3} are identified by adiabatic calorimetry. Three phase transitions, one at T{sub C3}(IV{yields}III)=30.7 K, the second at T{sub C2}(III{yields}II)=91.7 K (both accompanied by comparable entropy changes 3.0 and 3.1 J K{sup -1} mol{sup -1}, respectively) and the third at T{sub C1}(II{yields}I)=241.6 K (accompanied by an entropy change of 8.1 J K{sup -1} mol{sup -1}) were discovered. X-ray single crystal diffraction (at 293 K) demonstrates that phase I is a highly dynamic disordered cubic phase (Fm3{sup Macron }m, No. 225) with two types of BF{sub 4}{sup -} anions differing in a degree of disorder. In phase II (at 170 K) the structure remains cubic (Ia3{sup Macron }, No. 206), with two different types of cations and four different types of anions. Splitting of certain IR bands connected with NH{sub 3} ligands at the observed phase transitions suggests a lowering of the symmetry of the [Ru(NH{sub 3}){sub 6}]{sup 3+} complex cation. Both NH{sub 3} ligands and BF{sub 4}{sup -} anions perform fast reorientations ({tau}{sub R} Almost-Equal-To 10{sup -12} s), which are significantly slowed down below the phase transition at T{sub C3}. {sup 1}H NMR studies led to estimate the values of the activation energy of NH{sub 3} ligands reorientation in the phases II and I as equal to {approx}8 kJ mol{sup -1}. In phase I the whole hexammineruthenium(III) cations reorientation as a tumbling process can be noticed. The activation energy value of this motion is {approx}24 kJ mol{sup -1}. {sup 19}F NMR studies give the values of the activation energy of BF{sub 4}{sup -} anions reorientation as {approx}6 kJ mol{sup -1}. Above the phase transition temperature half of BF{sub 4}{sup -} anions perform a tumbling motion with E{sub a} Almost-Equal-To 8 kJ mol{sup -1}. - Graphical abstract: A series of complementary methods, such as Adiabatic Calorimetry, Differential Scanning Calorimetry, Fourier Transform-Far and Middle Spectroscopy, proton and fluorine Nuclear Magnetic Resonance and structural methods reveal information about phase transitions in [Ru(NH{sub 3}){sub 6}](BF{sub 4}){sub 3}. Highlights: Black-Right-Pointing-Pointer Three novel phase transitions are found in [Ru(NH{sub 3}){sub 6}](BF{sub 4}){sub 3}. Black-Right-Pointing-Pointer The thermodynamic parameters of the phase transitions are derived. Black-Right-Pointing-Pointer The transitions are of order-disorder type. Black-Right-Pointing-Pointer The complex belongs to Fm3{sup Macron }m at 293 K and its symmetry changes to Ia3{sup Macron} at 170 K. Black-Right-Pointing-Pointer [Ru(NH{sub 3}){sub 6}](BF{sub 4}){sub 3} is a highly dynamically disordered crystal.

Dolega, Diana, E-mail: dolega@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Mikuli, Edward, E-mail: mikuli@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Inaba, Akira, E-mail: inaba@chem.sci.osaka-u.ac.jp [Research Center for Structural Thermodynamics, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Gorska, Natalia, E-mail: gorska@chem.sci.osaka-u.ac.jp [Research Center for Structural Thermodynamics, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Holderna-Natkaniec, Krystyna, E-mail: natkanie@amu.edu.pl [Faculty of Physics, Adam Mickiewicz University, Umultowska 85, Poznan 61-614 (Poland); Nitek, Wojciech, E-mail: nitek@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland)

2013-01-15

327

Efficient sequential estimation for compound poisson processes  

Microsoft Academic Search

This paper discusses uniformly minimum variance, unbiased sequential estimation of a real-valued parametric function for a compound Poisson process when the compounding random variables belong to the exponential family. The characterization of Cramer-Rao efficient plans by Stefanov (1982 b) is shown to be incomplete by obtaining a new efficient plan for the compound Poisson-Bernoulli process. This new plan completes the

S. R. Adke; E. S. Murphree

1988-01-01

328

Estimating Markov-modulated compound Poisson processes  

Microsoft Academic Search

This paper addresses a parameter estimation problem for Markov-modulated compound Poisson process (MMCPP) and compound Markovian arrival process (CMAP). MMCPP and CMAP are extended from Markov-modulated Poisson process (MMPP) and Markovian arrival process (MAP) by combining compound Poisson process (CPP). The EM (expectation-maximization) algorithm is well known as an effective method in order to perform the statistical estimation for the

Hiroyuki Okamura; Yuya Kamahara; Tadashi Dohi

2007-01-01

329

Effect of Compound Sequence on Bitterness Enhancement  

Microsoft Academic Search

The nature and occurrence of carry-over effects, i.e. the response to a stimulus is influenced by previous samples, were examined for selected bitter compounds. A time-intensity procedure was used to rate the bitterness of six compounds (caffeine, denatonium benzoate, limonin, naringin, quinine and sucrose octa-acetate). For each subject concentrations of these compounds were determined that were approximately equal in intensity

Elba Cubero-Castillo; A. C. Noble

2001-01-01

330

Studies on drilling processes of intermetallic compounds  

Microsoft Academic Search

Intermetallic compounds have high-specific strength, good creep resistance and excellent oxidation and corrosion resistance at high temperatures. Those good mechanical properties make intermetallic compounds very promising structure materials in industries. Ni3Al and Fe3Al are two typical intermetallic compounds. This paper focuses on machinability and tool wear mechanism of PVD TiAlN coated cemented carbide tool in drilling of Ni3Al and Fe3Al.

L. Liu; H. Shao; L. X. Huang

2009-01-01

331

Compound cryopump for fusion reactors  

E-print Network

We reconsider an old idea: a three-stage compound cryopump for use in fusion reactors such as DEMO. The helium "ash" is adsorbed on a 4.5 K charcoal-coated surface, while deuterium and tritium are adsorbed at 15-22 K on a second charcoal-coated surface. The helium is released by raising the first surface to ~30 K. In a separate regeneration step, deuterium and tritium are released at ~110 K. In this way, the helium can be pre-separated from other species. In the simplest design, all three stages are in the same vessel, with a single valve to close the pump off from the tokamak during regeneration. In an alternative design, the three stages are in separate vessels, connected by valves, allowing the stages to regenerate without interfering with each other. The inclusion of the intermediate stage would not affect the overall pumping speed significantly. The downstream exhaust processing system could be scaled down, as much of the deuterium and tritium could be returned directly to the reactor. This could reduce ...

Kovari, M; Shephard, T

2013-01-01

332

Surface chemistry of organophosphorus compounds  

SciTech Connect

Heterogeneous reactions currently offer one of the most favorable technological routes to the removal of air pollutants from the atmosphere. Indeed, the application of heterogeneous catalytic methods to automotive emission control represents the most-widespread exposure of the public to the benefits of catalytic technology, costing the public about $3 billion annually for all automobiles and light-duty trucks manufactured in the United States. A more-specialized area of environmental protection involves the purification of breathing air in hazardous environments such as those exposed to chemical warfare agents. Degradation of pesticides and herbicides is a related area of importance. There is a pressing need to develop reliable methods to chemically transform into harmless substances, catalytically or stoichio-metrically, a variety of types of environmental threats. This paper reviews the known decomposition chemistry of organophosphorus compounds interacting with metal and metal oxide surfaces. Three kinds of processes - oxidation, dealkylation, and hydrolysis - are known to be important, but the fundamental knowledge base in this technologically and environmentally important area is presently inadequate. Some significant research directions are identified for surface chemical science, surface reaction chemistry, solid-state synthesis, and organometallic cluster chemistry.

Ekerdt, J.G.; Klabunde, K.J.; Shapley, J.R.; White, J.M.; Yates, J.T.

1988-01-01

333

Marine bacterial sources of bioactive compounds.  

PubMed

Thousands of novel compounds have been isolated from various marine bacteria and tested for pharmacological properties, many of which are commercially available. Many more are being tested as potential bioactive compound at the preclinical and clinical stages. The growing interest in marine-derived antiviral compounds, along with the development of new technology in marine cultures and extraction, will significantly expedite the current exploration of the marine environment for compounds with significant pharmacological applications, which will continue to be a promising strategy and new trend for modern medicine. Marine actinomycetes and cyanobacteria are a prolific but underexploited source for the discovery of novel secondary metabolites. PMID:22361201

Jaiganesh, R; Sampath Kumar, N S

2012-01-01

334

Persulfate Persistence and Treatability of Gasoline Compounds.  

E-print Network

??Petroleum hydrocarbons (PHCs) such as gasoline are ubiquitous organic compounds present at contaminated sites throughout the world. Accidental spills and leakage from underground storage tanks… (more)

Sra, Kanwartej Singh

2010-01-01

335

Hydrodesulfurization catalyst by Chevrel phase compounds  

DOEpatents

A process is disclosed for the hydrodesulfurization of sulfur-containing hydrocarbon fuel with reduced ternary molybdenum sulfides, known as Chevrel phase compounds. Chevrel phase compounds of the general composition M/sub x/Mo/sub 6/S/sub 8/, with M being Ho, Pb, Sn, Ag, In, Cu, Fe, Ni, or Co, were found to have hydrodesulfurization activities comparable to model unpromoted and cobalt-promoted MoS/sub 2/ catalysts. The most active catalysts were the ''large'' cation compounds (Ho, Pb, Sn), and the least active catalysts were the ''small'' cation compounds (Cu, Fe, Ni, Co.).

McCarty, K.F.; Schrader, G.L.

1985-05-20

336

ESTERIFICATION OF NATURAL COMPOUNDS WITH FATTY ACIDS.  

E-print Network

??In this PhD project we dealt with ?-sitosterol, resveratrol and quercetin, three natural substances featuring ascertained biological activities. These compounds are characterized by a limited… (more)

MAININI, FRANCESCA

2012-01-01

337

An isoperibol micro-bomb calorimeter for measurement of the enthalpy of combustion of organic compounds. Application to the study of succinic acid and acetanilide  

Microsoft Academic Search

A micro static-bomb combustion calorimeter, developed from a 1107 Parr semi-micro bomb, has been provided with a new micro-bomb and calorimetric bucket. In the best conditions of operation, the energy equivalent of this calorimetric arrangement is just ?(calor)=(731.82±0.22) J·K?1, which means an uncertainty of 0.03 per cent for the calibration with benzoic acid NIST 39j. This combustion calorimeter has been

Aarón Rojas; Alejandro Valdés

2003-01-01

338

Volatile organic compounds of Schenella pityophilus.  

PubMed

Volatile organic compounds of Schenella pityophilus have been identified via solid-phase microextraction-gas chromatography-mass spectrometry analysis. Ten compounds have been identified, in which 3-methylthio-1-propene was the most significant component. Some other components were previously identified in Tuber aestivum and Tuber melanosporum. PMID:22236093

D'Auria, Maurizio; Racioppi, Rocco; Rana, Gian Luigi

2013-01-01

339

Heterogeneous photocatalytic reactions of sulfur aromatic compounds.  

PubMed

Sulfur aromatic compounds, such as mono-, di-, tri-, and tetraalkyl-substituted thiophene, benzothiophenes, dibenzothiophenes, are the molecular components of many fossils (petroleum, oil shale, tar sands, bitumen). Structural units of natural, cross-linked heteroaromatic polymers present in brown coals, turf, and soil are similar to those of sulfur aromatic compounds. Many sulfur aromatic compounds are found in the streams of petroleum refining and upgrading (naphthas, gas oils) and in the consumer products (gasoline, diesel, jet fuels, heating fuels). Besides fossils, the structural fragments of sulfur aromatic compounds are present in molecules of certain organic semiconductors, pesticides, small molecule drugs, and in certain biomolecules present in human body (pheomelanin pigments). Photocatalysis is the frontier area of physical chemistry that studies chemical reactions initiated by absorption of photons by photocatalysts, that is, upon electronic rather than thermal activation, under "green" ambient conditions. This review provides systematization and critical review of the fundamental chemical and physicochemical information on heterogeneous photocatalysis of sulfur aromatic compounds accumulated in the last 20-30 years. Specifically, the following topics are covered: physicochemical properties of sulfur aromatic compounds, major classes of heterogeneous photocatalysts, mechanisms and reactive intermediates of photocatalytic reactions of sulfur aromatic compounds, and the selectivity of these reactions. Quantum chemical calculations of properties and structures of sulfur aromatic compounds, their reactive intermediates, and the structure of adsorption complexes formed on the surface of the photocatalysts are also discussed. PMID:21809426

Samokhvalov, Alexander

2011-11-18

340

A new active compound from Centaurea species.  

PubMed

The extract containing sesquiterpene lactones of Centaurea iberica (Asteraceae) isolated was separated and a steroidal compound, which is stigmast-1,5-dien-3beta-ol, was purified. The chemical structure was established based on spectroscopic data (UV, IR, MS, 1H NMR, 13C NMR). Both the extract and the compound showed significant antioxidant and antimicrobial activities. PMID:16610215

Dumlu, Melek U; Gürkan, Elcin

2006-01-01

341

Organochlorine Compounds and Risk of Breast Cancer  

Cancer.gov

Dr. Tongzhang Zheng, of Yale University, New Haven, CT, and colleagues conducted a hospital-based case-control study in Connecticut to investigate risk for breast cancer associated with exposure to organochlorine compounds. Levels of organochlorine compounds are being measured in breast adipose (fatty) tissue and blood serum obtained from women who had surgery or biopsies for breast cancer or benign breast disease.

342

Development of nonflammable potting compounds for spacecraft  

NASA Technical Reports Server (NTRS)

The requirements for nonflammable potting compounds for use in spacecraft electric and electronic equipment are discussed. The development of a suitable nonflammable compound is described. Flammability testing and acceptance criteria for Apollo spacecraft are presented. The dielectric properties of various ceramic materials used as conformal coatings are examined.

Kline, H. F.

1971-01-01

343

Microbial removal of hazardous organic compounds  

Microsoft Academic Search

An in-depth evaluation of the potential for microorganisms to remove anthropogenic organic compounds, mainly priority pollutants and related compounds, is presented. The evaluation indicates that use of properly selected populations of microbes, and the maintenance of environmental conditions most conducive to their metabolism, can be an important means of improving biological treatment of organic wastes. One major theme is that

Hester Kobayashi; B. E. Rittman

1982-01-01

344

PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH  

EPA Science Inventory

A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

345

Ambient Air Monitoring for Sulfur Compounds  

ERIC Educational Resources Information Center

A literature review of analytical techniques available for the study of compounds at low concentrations points up some of the areas where further research is needed. Compounds reviewed are sulfur dioxide, sulfuric acid, ammonium sulfate and bisulfate, metal sulfates, hydrogen sulfide, and organic sulfides. (BL)

Forrest, Joseph; Newman, Leonard

1973-01-01

346

Compounds from the roots of Jasminum sambac.  

PubMed

Four new compounds (+)-jasminoids A, B, C, and D, together with seven known compounds, were isolated from the roots of Jasminum sambac. Their structures were identified using spectroscopic methods. This study provides a better understanding to the chemical composition of J. sambac roots that have been thought to be one ingredient of an ancient prescription 'Ma-Fei-San'. PMID:23134371

Zeng, Lin-Hong; Hu, Min; Yan, Yong-Ming; Lu, Qing; Cheng, Yong-Xian

2012-01-01

347

Exploring marine resources for bioactive compounds.  

PubMed

Biodiversity in the seas is only partly explored, although marine organisms are excellent sources for many industrial products. Through close co-operation between industrial and academic partners, it is possible to successfully collect, isolate and classify marine organisms, such as bacteria, fungi, micro- and macroalgae, cyanobacteria, and marine invertebrates from the oceans and seas globally. Extracts and purified compounds of these organisms can be studied for several therapeutically and industrially significant biological activities, including anticancer, anti-inflammatory, antiviral, antibacterial, and anticoagulant activities by applying a wide variety of screening tools, as well as for ion channel/receptor modulation and plant growth regulation. Chromatographic isolation of bioactive compounds will be followed by structural determination. Sustainable cultivation methods for promising organisms and biotechnological processes for selected compounds can be developed, as well as biosensors for monitoring the target compounds. The (semi)synthetic modification of marine-based bioactive compounds produces their new derivatives, structural analogs and mimetics that could serve as hit or lead compounds and be used to expand compound libraries based on marine natural products. The research innovations can be targeted for industrial product development in order to improve the growth and productivity of marine biotechnology. Marine research aims at a better understanding of environmentally conscious sourcing of marine biotechnology products and increased public awareness of marine biodiversity. Marine research is expected to offer novel marine-based lead compounds for industries and strengthen their product portfolios related to pharmaceutical, nutraceutical, cosmetic, agrochemical, food processing, material and biosensor applications. PMID:25203732

Kiuru, Paula; D?Auria, M Valeria; Muller, Christian D; Tammela, Päivi; Vuorela, Heikki; Yli-Kauhaluoma, Jari

2014-09-01

348

Nitroaromatic Compounds, from Synthesis to Biodegradation  

PubMed Central

Summary: Nitroaromatic compounds are relatively rare in nature and have been introduced into the environment mainly by human activities. This important class of industrial chemicals is widely used in the synthesis of many diverse products, including dyes, polymers, pesticides, and explosives. Unfortunately, their extensive use has led to environmental contamination of soil and groundwater. The nitro group, which provides chemical and functional diversity in these molecules, also contributes to the recalcitrance of these compounds to biodegradation. The electron-withdrawing nature of the nitro group, in concert with the stability of the benzene ring, makes nitroaromatic compounds resistant to oxidative degradation. Recalcitrance is further compounded by their acute toxicity, mutagenicity, and easy reduction into carcinogenic aromatic amines. Nitroaromatic compounds are hazardous to human health and are registered on the U.S. Environmental Protection Agency's list of priority pollutants for environmental remediation. Although the majority of these compounds are synthetic in nature, microorganisms in contaminated environments have rapidly adapted to their presence by evolving new biodegradation pathways that take advantage of them as sources of carbon, nitrogen, and energy. This review provides an overview of the synthesis of both man-made and biogenic nitroaromatic compounds, the bacteria that have been identified to grow on and completely mineralize nitroaromatic compounds, and the pathways that are present in these strains. The possible evolutionary origins of the newly evolved pathways are also discussed. PMID:20508249

Ju, Kou-San; Parales, Rebecca E.

2010-01-01

349

Volatile organic compounds of Schenella pityophilus  

Microsoft Academic Search

Volatile organic compounds of Schenella pityophilus have been identified via solid-phase microextraction-gas chromatography–mass spectrometry analysis. Ten compounds have been identified, in which 3-methylthio-1-propene was the most significant component. Some other components were previously identified in Tuber aestivum and Tuber melanosporum.

Maurizio D’Auria; Rocco Racioppi; Gian Luigi Rana

2012-01-01

350

Methylation of mercury compounds by methylcobalamin  

Microsoft Academic Search

The methylation of mercuric chloride and certain organic mercury compounds by methylcobalamin in water solutions was studied by spectrophotometric and gas chromatographic methods. Methylcobalamin was found to react rapidly with mercuric chloride and at a slower rate with organic mercury compounds in water solutions. The ultimate products of the reaction with mercuric chloride were hydroxy-cobalamin and methylmercury cations as judged

L. Bertilsson; H. Y. Neujahr

1971-01-01

351

Compounding pharmacies: before and after an inspection.  

PubMed

Recent events have directed the U.S. Food and Drug Administration's attention to compounding pharmacies and have increased the frequency and vigorousness of pharmacy inspections. It is critical for compounding pharmacists to be prepared for such inspections and to understand their responsibilities after an inspection is over. PMID:24459779

Kulkarni, Darshan; Ricketts, Samantha

2013-01-01

352

Sulfur-containing compounds from Clinacanthus siamensis.  

PubMed

Two new sulfur-containing compounds, trans-3-methylsulfonyl-2-propenol (1) and trans-3-methylsulfinyl-2-propenol (2) were isolated together with trans-3-methylthioacrylamide (3), entadamide A (4) and entadamide C (5) from the leaves of Clinacanthus siamensis. The structures were established on the basis of the spectroscopic data. The compounds were tested for antimalarial and antimycobacterial activity. PMID:14646322

Tuntiwachwuttikul, Pittaya; Pootaeng-on, Yupa; Pansa, Pootchana; Srisanpang, Thongchai; Taylor, Walter Charles

2003-12-01

353

Perfluorinated Compounds: Emerging POPs with Potential Immunotoxicity  

EPA Science Inventory

Perfluorinated compounds (PFCs) have been recognized as an important class of environmental contaminants commonly detected in blood samples of both wildlife and humans. These compounds have been in use for more than 60 years as surface treatment chemicals, polymerization aids, an...

354

A multiprocess machine tool for compound micromachining  

Microsoft Academic Search

Compound micromachining is the most promising technology for the production of miniaturized parts and this technology is becoming increasingly more important and popular because of a growing demand for industrial products, with an increased number not only of functions but also of reduced dimensions, higher dimensional accuracy and better surface finish. Compound micromachining processes that combine multiple conventional and non-conventional

M. Rahman; A. B. M. A. Asad; T. Masaki; T. Saleh; Y. S. Wong; A Senthil Kumar

2010-01-01

355

(CHINA) PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH  

EPA Science Inventory

A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

356

Performance of BNL-TSTA compound cryopump  

SciTech Connect

A compound cryopump using cryocondensation pumping for hydrogen isotopes and cryosorption pumping with coconut charcoal as adsorbent for helium was designed. This compound cryopump was subsequently built (by Janis Research, Stoneham, MA) and has been tested at Brookhaven, fulfilling the design requirements and are delivered to Tritium Systems Test Assembly (TSTA) Vacuum Facility at Los Alamos Scientific Laboratory (LASL) for on-line operations.

Hseuh, H C; Worwetz, H A

1980-01-01

357

Volatile organic compounds in ambient aerosols  

NASA Astrophysics Data System (ADS)

In order to investigate the concentration levels of volatile organic compounds (VOCs) in ambient aerosols, monocyclic aromatic hydrocarbons (MAHs) and chlorinated hydrocarbons (CHs) in the particulate phase were measured simultaneously with those in the gas phase in the urban atmosphere. Six compounds were detected in the aerosols at concentrations from 0.051 (1,2-dichloroethane) to 1.75 ng m - 3 (benzene). Benzene was detected as the most dominant compound in the aerosols, although toluene was the most dominant compound in the gas phase. The VOCs in the aerosols had concentrations comparable to those reported for some semi-volatile organic compounds (SOCs) in the aerosols. The concentrations of the VOCs in the aerosols were primarily controlled by the aerosol mass loading. Temperature and relative humidity had no significant effect on the gas/particle partitioning of the VOCs. Our results also suggested that the hygroscopic properties of the aerosols should be considered to discuss the partitioning of the VOCs.

Matsumoto, Kiyoshi; Matsumoto, Kumi; Mizuno, Riichi; Igawa, Manabu

2010-07-01

358

Compound Poisson and signed compound Poisson approximations to the Markov binomial law  

Microsoft Academic Search

Compound Poisson distributions and signed compound Poisson measures are used for approximation of the Markov binomial distribution. The upper and lower bound estimates are obtained for the total variation, local and Wasserstein norms. In a special case, asymptotically sharp constants are calculated. For the upper bounds, the smoothing properties of compound Poisson distributions are applied. For the lower bound estimates,

V. Cekanavicius; P. Vellaisamy

2010-01-01

359

Cytotoxic compounds isolated from Murraya tetramera Huang.  

PubMed

A new compound and seven known compounds were isolated from Murraya tetramera Huang for the first time, and they were identified with NMR and MS spectral analysis. It was confirmed that the new compound was 10-methoxy-7-methyl-2H-benzo[g]chromen-2-one (3) and the others were ?-eudesmol (1), trans-3?-(1-hydroxy-1-methylethyl)-8a?-methyl-5-methylenedecalin-2-one (2), 5,7-dimethoxy-8-[(Z)-3'-methyl-butan-1',3'-dienyl]coumarin (4), 7-geranyloxy-6-methoxycoumarin (5), 5,7-dimethoxy-8-(3-methyl-2-oxo-butyl)coumarin (6), murrangatin acetate (7) and toddalenone (8). Furthermore, the cytotoxic activity against human lung adenocarcinoma (A549), human hepatocellular carcinoma cells (SMMC-7721), human bladder tumor cells (EJ), human cervical carcinoma cells (HeLa), and human B-lineage acute lymphoblastic leukemia 1 cells (BALL-1) was evaluated for all compounds. It was found that five of them displayed various degrees of cytotoxicity against different testing targets. Compound 1 showed significant cytotoxic activity against the five cell lines (A549, SMMC-7721, EJ, Hela and BALL-1). Compounds 2 and 5 showed significant cytotoxicity against three cell lines (A549, SMMC-7721 and BALL-1). Compound 4 showed significant cytotoxicity against three cell lines (A549, EJ and BALL-1). However, compound 3 only showed fair cytotoxicity against the BALL-1 cell line. The structure-active relationships were investigated as well. These active compounds might be potential lead compounds for the treatment of cancer. PMID:25165861

You, Chun-Xue; Yang, Kai; Wang, Cheng-Fang; Zhang, Wen-Juan; Wang, Ying; Han, Jiao; Fan, Li; Du, Shu-Shan; Geng, Zhu-Feng; Deng, Zhi-Wei

2014-01-01

360

Compound estimation procedures in reliability  

NASA Technical Reports Server (NTRS)

At NASA, components and subsystems of components in the Space Shuttle and Space Station generally go through a number of redesign stages. While data on failures for various design stages are sometimes available, the classical procedures for evaluating reliability only utilize the failure data on the present design stage of the component or subsystem. Often, few or no failures have been recorded on the present design stage. Previously, Bayesian estimators for the reliability of a single component, conditioned on the failure data for the present design, were developed. These new estimators permit NASA to evaluate the reliability, even when few or no failures have been recorded. Point estimates for the latter evaluation were not possible with the classical procedures. Since different design stages of a component (or subsystem) generally have a good deal in common, the development of new statistical procedures for evaluating the reliability, which consider the entire failure record for all design stages, has great intuitive appeal. A typical subsystem consists of a number of different components and each component has evolved through a number of redesign stages. The present investigations considered compound estimation procedures and related models. Such models permit the statistical consideration of all design stages of each component and thus incorporate all the available failure data to obtain estimates for the reliability of the present version of the component (or subsystem). A number of models were considered to estimate the reliability of a component conditioned on its total failure history from two design stages. It was determined that reliability estimators for the present design stage, conditioned on the complete failure history for two design stages have lower risk than the corresponding estimators conditioned only on the most recent design failure data. Several models were explored and preliminary models involving bivariate Poisson distribution and the Consael Process (a bivariate Poisson process) were developed. Possible short comings of the models are noted. An example is given to illustrate the procedures. These investigations are ongoing with the aim of developing estimators that extend to components (and subsystems) with three or more design stages.

Barnes, Ron

1990-01-01

361

Flavonoids and phenolic compounds from Rosmarinus officinalis.  

PubMed

A new flavonoid, 6''-O-(E)-feruloylhomoplantaginin (1), and 14 known compounds, 6''-O-(E)-feruloylnepitrin (2), 6''-O-(E)-p-coumaroylnepitrin (3), 6-methoxyluteolin 7-glucopyranoside (4), luteolin 3'-O-beta-D-glucuronide (5), luteolin 3'-O-(3''-O-acetyl)-beta-D-glucuronide (6), kaempferol (7), luteolin (8), genkwanin (9), and ladanein (10), together with 1-O-feruloyl-beta-D-glucopyranose (11), 1-O-(4-hydroxybenzoyl)-beta-D-glucopyranose (12), rosmarinic acid (13), carnosic acid (14), and carnosol (15), were isolated from the leaves of Rosmarinus officinalis . The structures were established on the basis of NMR spectroscopic methods supported by HRMS. All isolated compounds were tested for cytotoxicity in human cancer cell lines (HepG2, COLO 205, and HL-60) and for anti-inflammatory activities in lipopolysaccharide (LPS)-treated RAW 264.7 macrophage cells. Among them, compounds 14 and 15 were modestly active in the inhibition of nitrite production in macrophages, followed by compounds 8 and 5. Compounds 14 and 15 were more effective as an antiproliferative agent in HL-60 cells with IC(50) values of 1.7 and 5.5 microM, followed by compounds 8 and 7 with IC(50) of 39.6 and 82.0 microM, respectively. In addition, compounds 14 and 15 showed potent antiproliferative effects on COLO 205 cells with IC(50) values of 32.8 and 29.9 microM, respectively. PMID:20397728

Bai, Naisheng; He, Kan; Roller, Marc; Lai, Ching-Shu; Shao, Xi; Pan, Min-Hsiung; Ho, Chi-Tang

2010-05-12

362

Risk and liabilities of prescribing compounded medications.  

PubMed

Complications resulting from the use of compounded medications have become a troubling trend nationwide. There is a significant potential for patients to suffer serious harm from the use of substandard medications prepared by compounding pharmacies, and the reality of this problem has been demonstrated in several well-publicized incidences of serious medical complications, including patient deaths, that directly resulted from the use of medications prepared at compounding pharmacies. Unlike US Food and Drug Administration (FDA)-approved drugs, compounded products are not required to meet evidentiary standards for establishing safety and efficacy. Moreover, these products are not held to Good Manufacturing Practices, which require regular inspections, quality control testing, and rejection of material not meeting specifications. Physicians, as well as other prescribers, need to be aware that when a patient suffers harm from using a compounded medication, those injured patients may bring negligence and malpractice claims, not only against the pharmacy and the pharmacist responsible for preparing the medication, but also against the prescribing physician and the physician’s practice. Consequently, the best way for physicians to manage professional risk and avoid both litigation and potential negative patient outcomes related to compounded pharmaceuticals is to not use these products if there is an FDA-approved product available. However, if the use of a compounded medication is medically necessary, then physicians should adhere to the FDA guidance concerning traditional compounding. Moreover, it would be prudent for any physician who intends to either resell or participate in the distribution of compounded products beyond the direct treatment of their patients to consider obtaining the appropriate insurance coverage for this activity. PMID:25276868

Randell, Michael D; Duffy, Phillip J

2014-07-01

363

Triaryl Pyrazoline Compound Inhibits Flavivirus RNA Replication  

Microsoft Academic Search

Triaryl pyrazoline {(5-(4-chloro-phenyl)-3-thiophen-2-yl-4,5-dihydro-pyrazol-1-yl)-phenyl-methanone} in- hibits flavivirus infection in cell culture. The inhibitor was identified through high-throughput screening of a compound library using a luciferase-expressing West Nile (WN) virus infection assay. The compound inhibited an epidemic strain of WN virus without detectable cytotoxicity (a 50% effective concentration of 28 M and a compound concentration of >300 M required to reduce 50%

Francesc Puig-Basagoiti; Mark Tilgner; Brett M. Forshey; Sean M. Philpott; Noel G. Espina; David E. Wentworth; Scott J. Goebel; Paul S. Masters; Barry Falgout; Ping Ren; David M. Ferguson; Pei-Yong Shi

2006-01-01

364

Application of bicyclic and cage compounds  

NASA Technical Reports Server (NTRS)

The results of a literature survey of the field of bicyclic and cage compounds were presented, with the objective of identifying those types of compounds with unusual physical and chemical stability, and determining what practical applications have been found for these compounds. Major applications have been as polymers, polymer additives, medicinals, and pesticides. Lesser applications have included fuels, fuel additives, lubricants, lubricant additives, and perfumes. Several areas where further work might be useful were also outlined; these are primarily in the areas of polymers, polymer additives, medicinals, and synthetic lubricants.

Clark, R. D.; Archuleta, B. S.

1976-01-01

365

Molecular basis of biodegradation of chloroaromatic compounds  

SciTech Connect

Chlorinated aromatic hydrocarbons are widely used in industry and agriculture and comprise the bulk of environmental pollutants. Although simple aromatic compounds are biodegradable by a variety of degradative pathways, their halogenated counterparts are more resistant to bacterial attack and often necessitate evolution of novel pathways. An understanding of such evolutionary processes is essential for developing genetically improved strains capable of mineralizing highly chlorinated compounds. The article provides an overview of the genetic aspects of dissimilation of chloroaromatic compounds and discusses the potential of gene manipulation to promote enhanced evolution of the degradative pathways.

Sangodkar, U.M.X.; Aldrich, T.L.; Haugland, T.L.; Johnson, R.A.; Rothmel, R.K.

1989-01-01

366

A growing codependency: compounding pharmacy and safety.  

PubMed

Pharmacists and pharmacy technicians are in constant contact with potent compounds. When compounding with powders, there is a susceptibility to environmental conditions such that proper containment be in place to keep the employees safe, the medicine free from cross contamination or the introduction of outside contaminants, and the workplace free from floating active pharmaceutical ingredient particles. Adapting powder hoods as safety devices that work in direct relation to clearly defined standard operating procedures and good lab practices will facilitate a safer lab environment for employees and ensure good-quality prescriptions. This article discusses the safety concerns of compounding with powders and the safety measures to consider when purchasing powder hoods. PMID:24579299

Prince, Bryan; Lundevall, Jeremy

2013-01-01

367

Microdosimetric evaluations of boron compound efficacy  

SciTech Connect

The ideal boron compound for application in boron neutron capture therapy (BNCT) should be selectively accumulated in tumor with concomitantly low concentrations in neighboring normal tissues and blood. As the presumed target of lethal radiation is the nucleus, an intracellular and, optimally, intranuclear localization of boron would be preferred. Boronated nucleosides, nucleotides, and DNA-intercalators have been synthesized in pursuit of this goal. This paper describes an approach to predict the relative biological effectiveness (RBE) values for such boron compounds. The results of this study may prove useful for future boron compound development for BNCT.

Yam, C.S. [Massschusets Institute of Technology, Cambridge, MA (United States); Zamenhof, R.G.; Solares, G.R. [Tufts New England Medical Center, Boston, MA (United States)

1995-12-31

368

Calorimetric Study of Thermal Denaturation of ?-Lactoglobulin  

Microsoft Academic Search

Effects of pH and milk constituents (milk ultrafiltrate and ~:-casein) on de- naturation of fl-lactoglobulin were investi- gated by a dynamic method based on dif- ferential scanning calorimetry. The appar- ent reaction order of \\/Ltactoglobulin de- naturation by the dynamic method was 2.0 over the pH range of 4.0 to 9.0, which is in fair agreement with results by other

Kwan Hwa Park; Daryl B. Lund

1984-01-01

369

Extraction and isolation of phenolic compounds.  

PubMed

Phenolic compounds constitute a major class of plant secondary metabolites that are widely distributed in the plant kingdom and show a large structural diversity. These compounds occur as aglycones or glycosides, as monomers or constituting highly polymerized structures, or as free or matrix-bound compounds. Furthermore, they are not uniformly distributed in the plant and their stability varies significantly. This greatly complicates their extraction and isolation processes, which means that a single standardized procedure cannot be recommended for all phenolics and/or plant materials; procedures have to be optimized depending on the nature of the sample and the target analytes, and also on the object of the study. In this chapter, the main techniques for sample preparation, and extraction and isolation of phenolic compounds have been reviewed-from classical solvent extraction procedures to more modern approaches, such as the use of molecularly imprinted polymers or counter-current chromatography. PMID:22367907

Santos-Buelga, Celestino; Gonzalez-Manzano, Susana; Dueñas, Montserrat; Gonzalez-Paramas, Ana M

2012-01-01

370

Clinical testing of new antimalarial compounds*  

PubMed Central

More than 200 000 chemical compounds have been screened for antimalarial activity over the past 10 years by the US Army Antimalarial Drug Development Program. By means of extensive animal testing, 26 of these compounds were selected for clinical study in human subjects volunteering for such trials. Of these, 7 have received complete clinical trials and are in various stages of field evaluation, 4 are currently undergoing clinical trial, and 2 are still awaiting testing in volunteer subjects. Thus far, 2 compounds (WR 33 063 and WR 30 090) have demonstrated greater activity against drug-resistant Plasmodium falciparum than any other known drug. Several other compounds presently being tested in human subjects are even more potent. PMID:4613503

Canfield, C. J.; Rozman, R. S.

1974-01-01

371

Microwave spectra of some volatile organic compounds  

NASA Technical Reports Server (NTRS)

A computer-controlled microwave (MRR) spectrometer was used to catalog reference spectra for chemical analysis. Tables of absorption frequency, peak absorption intensity, and integrated intensity are included for 26 volatile organic compounds, all but one of which contain oxygen.

White, W. F.

1975-01-01

372

Botanical compounds: effects on major eye diseases.  

PubMed

Botanical compounds have been widely used throughout history as cures for various diseases and ailments. Many of these compounds exhibit strong antioxidative, anti-inflammatory, and antiapoptotic properties. These are also common damaging mechanisms apparent in several ocular diseases, including age-related macular degeneration (AMD), glaucoma, diabetic retinopathy, cataract, and retinitis pigmentosa. In recent years, there have been many epidemiological and clinical studies that have demonstrated the beneficial effects of plant-derived compounds, such as curcumin, lutein and zeaxanthin, danshen, ginseng, and many more, on these ocular pathologies. Studies in cell cultures and animal models showed promising results for their uses in eye diseases. While there are many apparent significant correlations, further investigation is needed to uncover the mechanistic pathways of these botanical compounds in order to reach widespread pharmaceutical use and provide noninvasive alternatives for prevention and treatments of the major eye diseases. PMID:23843879

Huynh, Tuan-Phat; Mann, Shivani N; Mandal, Nawajes A

2013-01-01

373

Stabilized lanthanum sulphur compounds. [thermoelectric materials  

NASA Technical Reports Server (NTRS)

Lanthanum sulfide is maintained in the stable cubic phase form over a temperature range of from 500 C to 1500 C by adding to it small amounts of calcium, barium, or strontium. This compound is an excellent thermoelectric material.

Reynolds, G. H.; Elsner, N. B.; Shearer, C. H. (inventors)

1983-01-01

374

Identification of Aneuploidy-Selective Antiproliferation Compounds  

E-print Network

Aneuploidy, an incorrect chromosome number, is a hallmark of cancer. Compounds that cause lethality in aneuploid, but not euploid, cells could therefore provide new cancer therapies. We have identified the energy stress-inducing ...

Tang, Yun-Chi

375

ANALYSIS OF FISH HOMOGENATES FOR PERFLUORINATED COMPOUNDS  

EPA Science Inventory

Perfluorinated compounds (PFCs) which include PFOS and PFOA are widely distributed in wildlife. Whole fish homogenates were analyzed for PFCs from the upper Mississippi, the Missouri and the Ohio rivers. Methods development, validation data, and preliminary study results will b...

376

Food applications of natural antimicrobial compounds  

PubMed Central

In agreement with the current trend of giving value to natural and renewable resources, the use of natural antimicrobial compounds, particularly in food and biomedical applications, becomes very frequent. The direct addition of natural compounds to food is the most common method of application, even if numerous efforts have been made to find alternative solutions to the aim of avoiding undesirable inactivation. Dipping, spraying, and coating treatment of food with active solutions are currently applied to product prior to packaging as valid options. The aim of the current work is to give an overview on the use of natural compounds in food sector. In particular, the review will gather numerous case-studies of meat, fish, dairy products, minimally processed fruit and vegetables, and cereal-based products where these compounds found application. PMID:23060862

Lucera, Annalisa; Costa, Cristina; Conte, Amalia; Del Nobile, Matteo A.

2012-01-01

377

HEALTH EFFECTS ASSESSMENT FOR BORON AND COMPOUNDS  

EPA Science Inventory

The report summarizes and evaluates information relevant to a preliminary interim assessment of adverse health effects associated with specific chemicals or compounds. The Office of Emergency and Remedial Response (Superfund) uses these documents in preparing cost-benefit analyse...

378

HEALTH EFFECTS ASSESSMENT FOR TIN AND COMPOUNDS  

EPA Science Inventory

The report summarizes and evaluates information relevant to a preliminary interim assessment of adverse health effects associated with specific chemicals or compounds. The Office of Emergency and Remedial Response (Superfund) uses these documents in preparing cost-benefit analyse...

379

Febrifugine analogue compounds: synthesis and antimalarial evaluation.  

PubMed

Febrifugine is an alkaloid isolated from Dichroa febrifuga Lour as the active component against Plasmodium falciparum, but exhibits toxic side effects. In this study novel febrifugine analogues were designed and efficiently synthesized. New compounds underwent efficacy and toxicity evaluation. Some compounds are much less toxic than the natural product febrifugine and existing antimalarial drugs and are expected to possess wide therapeutic windows. In Aotus monkeys infected with the chloroquine resistant FVO strain of P. falciparum, one interesting compound possesses a 50% curative dose of 2mg/kg/day and a 100% curative dose of 8 mg/kg/day. These compounds, as well as the underlying design rationale, may find usefulness in the discovery and development of new antimalarial drugs. PMID:22182577

Zhu, Shuren; Chandrashekar, Gudise; Meng, Li; Robinson, Katie; Chatterji, Dipsanker

2012-01-15

380

Perfluorinated Compounds In The Ohio River Basin  

EPA Science Inventory

Contaminants of emerging concern (CECs) in waterways include pharmaceuticals and personal care products (PPCPs), alkylphenols, endocrine disrupting chemicals (EDCs) and perfluorinated alkyl compounds (PFCs). Their distributions and persistence in the aquatic environment remain p...

381

Antibacterial Effect of Some Azaphenanthrene Compounds  

PubMed Central

Five newly synthesized azaphenanthrene compounds have been studied for their antibacterial activity, which to varying degrees was shown to be related to the position of the aza, methyl, and benzyl groups in the ring. PMID:5456010

Gupta, K. G.; Kessar, S. V.; Singh, Baldev

1970-01-01

382

HEALTH EFFECTS ASSESSMENT FOR ANTIMONY AND COMPOUNDS  

EPA Science Inventory

The report summarizes and evaluates information relevant to a preliminary interim assessment of adverse health effects associated with specific chemicals or compounds. The Office of Emergency and Remedial Response (Superfund) uses these documents in preparing cost-benefit analyse...

383

The Compounding Parameter in Second Language Acquisition.  

ERIC Educational Resources Information Center

Investigates the compounding parameter in the second language (L2) Spanish interlanguage of English and French native speakers in light of the subset principle and its predictions for the process of L2 development. (Author/VWL)

Slabakova, Roumyana

2002-01-01

384

Two new compounds from Potentilla multicaulis Bunge.  

PubMed

Two new compounds (triterpenoid saponin and heterocyclic compound), 2?,3?, 19?,23,30-pentahydroxyurs-12-en-28-oic acid-28-O-?-d-glucopyranosyl ester (1) and N-hydroxyl-hexahydroazepin-2,4-diones (2), with 11 known compounds, picein (3), (7S,8R)-dihydrodehydrodiconiferyl alcohol-9'-O-?-d-glucopyranoside (4), (+)-1-hydroxy-2-epipinoresinol-1-?-d-glucoside (5), (+)-1-hydroxypinoresinol-1-?-d-glucoside (6), (+)-1-hydroxypinoresinol-4'-?-d-glucoside (7), schaftside (6-C-?-d-glucopyranosyl-8-C-?-l-arabinosyl apigenin) (8), isoschaftside (6-C-?-l-arabinosyl-8-C-?-d-glucopyranosyl apigenin) (9), isorhamnetin-3-O-?-d-glucopyranoside (10), quercetin-3-O-?-glucuronide (11), 8-O-methylherbacetin-3-O-sophoroside (12) and kaempferol (13), were isolated from Potentilla multicaulis Bunge. The structure of the compounds was elucidated by chemical and spectral evidence. PMID:23148512

Jia, Lingyun; Wang, Jing; Lv, Chongning; Xu, Tanye; He, Lihua; Dong, Yan; Lu, Jincai

2013-08-01

385

ATMOSPHERIC CHEMISTRY OF SEVERAL TOXIC COMPOUNDS  

EPA Science Inventory

The hydroxyl radical initiated gas phase oxidation of several toxic compounds in nitrous acid, oxides of nitrogen, in air mixtures were investigated. The chemical species studied were: formaldehyde, acrylonitrile, vinylidene chloride, trichloroethylene, allyl chloride, acetaldehy...

386

Reorganizations of complex networks: Compounding and reducing  

NASA Astrophysics Data System (ADS)

Real networks interact with each other by different kinds of topological connections, which are usually demonstrated by linking nodes of different networks. Simple connection, such as one-to-one corresponding, random connection and similar connection are adopted for studying the interacted networks. Practical interrelations established between the two networks are ignored. In this study, a generalized framework of multi-subnet composited complex network that allowed us to investigate interrelations among several subnets is developed. Based on that, reorganizations of networks: compounding (compound subnets into a "bigger" one) and reducing (obtain a "smaller" network from a "bigger" one) are proposed. As an empirical evidence, influence of compounding on traffic dynamics is discussed. And the properties of nodes linking two networks are also considered. Onset of compounding between two networks is revealed. Numerical simulations on artificial networks as well as real bus and tube networks of Qingdao in China agree well with our analysis, which show validity of our model.

Shao, Fengjing; Sui, Yi

2014-12-01

387

Botanical Compounds: Effects on Major Eye Diseases  

PubMed Central

Botanical compounds have been widely used throughout history as cures for various diseases and ailments. Many of these compounds exhibit strong antioxidative, anti-inflammatory, and antiapoptotic properties. These are also common damaging mechanisms apparent in several ocular diseases, including age-related macular degeneration (AMD), glaucoma, diabetic retinopathy, cataract, and retinitis pigmentosa. In recent years, there have been many epidemiological and clinical studies that have demonstrated the beneficial effects of plant-derived compounds, such as curcumin, lutein and zeaxanthin, danshen, ginseng, and many more, on these ocular pathologies. Studies in cell cultures and animal models showed promising results for their uses in eye diseases. While there are many apparent significant correlations, further investigation is needed to uncover the mechanistic pathways of these botanical compounds in order to reach widespread pharmaceutical use and provide noninvasive alternatives for prevention and treatments of the major eye diseases. PMID:23843879

Huynh, Tuan-Phat; Mann, Shivani N.; Mandal, Nawajes A.

2013-01-01

388

New twisted intermetallic compound superconductor: A concept  

NASA Technical Reports Server (NTRS)

Method for processing Nb3Sn and other intermetallic compound superconductors produces a twisted, stabilized wire or tube which can be used to wind electromagnetics, armatures, rotors, and field windings for motors and generators as well as other magnetic devices.

Coles, W. D.; Brown, G. V.; Laurence, J. C.

1972-01-01

389

Testing Compounds for Efficacy against Schistosomiasis.  

National Technical Information Service (NTIS)

During this four year funding period, attempts were made to determine the efficacy of the compound Niclosamide as a potential Topical Antipenetrant (TAP) against cercariae (ineffective larval) of Schistosoma mansoni, S. haemotobium, and S.japonicum in mon...

J. I. Bruce

1990-01-01

390

Stopped Compound Poisson Process and Related Distributions  

Microsoft Academic Search

This chapter considers the first-crossing problem of a compound Poisson process with positive integer-valued jumps in a nondecreasing lower boundary. The cases where the boundary is a given linear function, a standard renewal process, or an arbitrary deterministic function\\u000a are successively examined. Our interest is focused on the exact distribution of the first-crossing level (or time) of the compound Poisson

Claude Lefèvre

391

Membrane air-stripping of aroma compounds  

Microsoft Academic Search

The selective extraction of aroma compounds from a highly diluted aqueous feed by membrane air-stripping (MAS) was studied. The pilot-scale apparatus used for this study was made of a hollow fiber membrane contactor coupled with a multi-step condensation unit. The aqueous feed model solution containing 10 aroma compounds (at ?2×10?2kgm?3 each) cross-flowed on the shell side of the membrane and

F. Gascons Viladomat; I. Souchon; V. Athès; M. Marin

2006-01-01

392

Medical Applications and Toxicities of Gallium Compounds  

PubMed Central

Over the past two to three decades, gallium compounds have gained importance in the fields of medicine and electronics. In clinical medicine, radioactive gallium and stable gallium nitrate are used as diagnostic and therapeutic agents in cancer and disorders of calcium and bone metabolism. In addition, gallium compounds have displayed anti-inflammatory and immunosuppressive activity in animal models of human disease while more recent studies have shown that gallium compounds may function as antimicrobial agents against certain pathogens. In a totally different realm, the chemical properties of gallium arsenide have led to its use in the semiconductor industry. Gallium compounds, whether used medically or in the electronics field, have toxicities. Patients receiving gallium nitrate for the treatment of various diseases may benefit from such therapy, but knowledge of the therapeutic index of this drug is necessary to avoid clinical toxicities. Animals exposed to gallium arsenide display toxicities in certain organ systems suggesting that environmental risks may exist for individuals exposed to this compound in the workplace. Although the arsenic moiety of gallium arsenide appears to be mainly responsible for its pulmonary toxicity, gallium may contribute to some of the detrimental effects in other organs. The use of older and newer gallium compounds in clinical medicine may be advanced by a better understanding of their mechanisms of action, drug resistance, pharmacology, and side-effects. This review will discuss the medical applications of gallium and its mechanisms of action, the newer gallium compounds and future directions for development, and the toxicities of gallium compounds in current use. PMID:20623028

Chitambar, Christopher R.

2010-01-01

393

Photometabolism of aromatic compounds by Rhodopseudomonas palustris  

Microsoft Academic Search

The phototrophic bacteriumRhodopseudomonas palustris has been reported to be versatile in photometabolism of aromatic compounds. However, the kinetics of degradation of aromatic compounds byR. palustris appears not to have been reported in the literature. In this laboratory a photosynthetic bacterium that was identified asRhodopseudomonas palustris(bp) was isolated from a sample collected from a canal where refinery wastewater was discharged. The

S. B. Rahalkar; S. R. Joshi; N. Shivaraman

1993-01-01

394

On the dimerization process of nitroso compounds  

Microsoft Academic Search

Summary Many organic C-nitroso compounds R-NO form stable dimers with a covalent NN bond. To gain insight into the dimerization reaction 2 R-NO ? (R-NO)2 a theoretical study of the dimerization to atrans-form was performed using HNO as a model compound. Complete geometry optimizations were carried out at the HF, MP2 and QCISD levels using a 6–31G* basis. In the

W. Lüttke; P. N. Skancke; M. Traetteberg

1994-01-01

395

Metal Compounds in Therapy and Diagnosis  

NASA Astrophysics Data System (ADS)

There is increasing interest in the use of metal-containing compounds in medicine. This review describes several therapeutic applications, such as the use of platinum complexes in cancer chemotherapy, gold compounds in the treatment of arthritis, gallium in hypercalcemia, bismuth in anti-ulcer medication, and sodium nitroprusside in hypertension. The use of metal radionuclides in diagnosis and radiotherapy and the role of paramagnetic metal complexes as contrast agents in magnetic resonance imaging are also discussed.

Abrams, Michael J.; Murrer, Barry A.

1993-08-01

396

Bioremediation and phytoremediation: Chlorinated and recalcitrant compounds  

SciTech Connect

Bioremediation and phytoremediation have progressed, especially with regard to the treatment of hydrocarbon-contaminated sites. Sites contaminated with chlorinated and recalcitrant compounds have proven more resistant to these approaches, but exciting progress is being made both in the laboratory and in the field. This book brings together the latest breakthrough thinking and results in bioremediation, with chapters on cometabolic processes, aerobic and anaerobic mechanisms, biological reductive dechlorination processes, bioaugmentation, biomonitoring, and phytoremediation of recalcitrant organic compounds.

NONE

1998-12-31

397

Fig volatile compounds—a first comparative study  

Microsoft Academic Search

We analysed the compounds of volatile blends released by receptive figs of twenty Ficus species to attract their specific pollinating wasps. In all, 99 different compounds were identified. The compounds are mainly terpenoids, aliphatic compounds and products from the shikimic acid pathway. In each species blend, there are few major compounds, which are generally common among floral fragrances. Most species

Laure Grison-Pigé; Martine Hossaert-McKey; Jaco M. Greeff; Jean-Marie Bessière

2002-01-01

398

Antinociceptive effects of tetrahydrophthalimides and related compounds.  

PubMed

This paper describes the antinociceptive effects of tetrahydrophthalimides and related compounds in mice. Twenty compounds were obtained by the reaction of cis-1,2,3,6-tetrahydrophthalic anhydride with appropriate amines, dehydration, and addition to the imidic double bond. They were analyzed in the writhing test at 10 mg/kg given intraperitoneally. The most active compound 2-benzyl-5-morpholin-4-yl-hexahydroisoindole-1,3-dione (19) was studied on formalin, capsaicin, glutamate and hot plate models. The antinociceptive activity demonstrated by some studied compounds is promising, and some of them were more active than acetylsalicylic acid and paracetamol used as reference drugs in writhing tests in mice. Compound 19 was about 5-fold more potent than the reference drugs, being also effective by oral route and against the inflammatory response in the formalin test. The results suggest that compound 19 could be used as a model to obtain new and more potent antinociceptive agents. It exhibits an interesting antinociceptive profile, and does not interact with opioid systems. PMID:17542485

Costa, Bianca B C; Corrêa, Rogério; De Souza, Marcia M; Pretto, Juliana B; Ardenghi, Juliana V; De Campos-Buzzi, Fátima; Cechinel Filho, Valdir

2007-01-01

399

Excitonic effects in oxyhalide scintillating host compounds  

NASA Astrophysics Data System (ADS)

Ab-initio calculations based on density functional theory have been performed to study the electronic, optical, mechanical, and vibrational properties of scintillator host compounds YOX (X = F, Cl, Br, and I). Semiempirical dispersion correction schemes are used to find the effect of van der Waals forces on these layered compounds and we found this effect to be negligible except for YOBr. Calculations of phonons and elastic constants showed that all the compounds studied here are both dynamically and mechanically stable. YOF and YOI are found to be indirect band gap insulators while YOCl and YOBr are direct band gap insulators. The band gap is found to decrease as we move from fluorine to iodine, while the calculated refractive index shows the opposite trend. As the band gap decreases on going down the periodic table from YOF to YOI, the luminescence increases. The excitonic binding energy calculated, within the effective mass approximation, is found to be more for YOF than the remaining compounds, suggesting that the excitonic effect to be more in YOF than the other compounds. The optical properties are calculated within the Time-Dependent Density Functional Theory (TDDFT) and compared with results obtained within the random phase approximation. The TDDFT calculations, using the newly developed bootstrap exchange-correlation kernel, showed significant excitonic effects in all the compounds studied here.

Shwetha, G.; Kanchana, V.; Valsakumar, M. C.

2014-10-01

400

Compounding pharmacies: who is in charge?  

PubMed

Compounding pharmacies play an increasing and increasingly important role in our healthcare system, but recent media attention has exposed limited regulatory control over these organizations at the same time their role is expanding. Compounding pharmacies are not regulated in the same manner as pharmaceutical companies and are governed largely by Chapter <797>, a monograph on the pharmaceutical compounding of sterile products, issued but not enforced by the U.S. Pharmacopeial Convention. Not all states require adherence to Chapter <797>, and those that do may choose not to enforce it stringently. Furthermore, Chapter <797> is not a strong standard--for example, it does not require documentation of drug lot numbers or cross-references for patient identification. Thus, there have long been many potential quality issues associated with compounding pharmacies. As these compounding pharmacies provide important products and services, better regulation is urgently needed. Moreover, clinicians should be better aware that some injectable products they use may have been prepared by a compounding pharmacy. PMID:23350709

Pergolizzi, Joseph V; Labhsetwar, Sumedha; LeQuang, Jo Ann

2013-03-01

401

Continuous dielectrophoretic centering of compound droplets  

NASA Astrophysics Data System (ADS)

Compound droplets, or droplets-within-droplets, are traditionally key components in applications ranging from drug delivery to the food industry. Presently, millimeter-sized compound droplets are precursors for foam shell targets in inertial fusion energy work. A key constraint is a uniform foam shell thickness, which in turn requires a centered core in the compound droplet precursor. Previously, Bei et al. (2009, 2010) have shown that compound droplets could be centered in a static fluid using an electric field of 0.7 kV/cm at 20 MHz. To apply centering to existing or future applications, it is imperative to develop a continuous droplet centering process by overcoming the additional complications from motion. Here, we present analysis and experimental data of a continuous droplet centering device that uses an electric field to force a core droplet to the center of a moving compound drop. Our analysis focuses on how interfacial rheology and electrohydrodynamic flows affect the centering dynamics and droplet deformation. Proof-of-principle experiments are performed in a vertical channel using buoyancy to drive a solution of compound droplets stabilized with phospholipid and protein emulsifiers through a kV/cm electric field.

Randall, Greg; Blue, Brent

2012-02-01

402

Ultraviolet radiation absorbing compounds in marine organisms  

SciTech Connect

Studies on the biological effects of solar ultraviolet radiations are becoming increasingly common, in part due to recent interest in the Antarctic ozone hole and in the perceived potential for global climate change. Marine organisms possess many strategies for ameliorating the potentially damaging effects of UV-B (280-320 nm) and the shorter wavelengths of UV-A (320-400nm). One mechanism is the synthesis of bioaccumulation of ultraviolet radiation absorbing compounds. Several investigators have noted the presence of absorbing compounds in spectrophotometer scans of extracts from a variety of marine organisms, particularly algae and coelenterates containing endosymbiotic algae. The absorbing compounds are often mycosporine-like amino acids. Thirteen mycosporine-like amino acids have already been described, and several others have recently been detected. Although, the mycosporine-like amino acids are widely distributed. these compounds are by no means the only type of UV-B absorbing compounds which has been identified. Coumarins from green algae, quinones from sponges, and indoles from a variety of sources are laternative examples which are documented in the natural products literature. When the biological impact of solar ultraviolet radiation is assessed, adequate attention must be devoted to the process of photoadaptation, including the accumulation of ultraviolet radiation absorbing compounds.

Chalker, B.E.; Dunlap, W.C. (Australian Inst. of Marine Science, Queensland (Australia))

1990-01-09

403

Spectroscopic and calorimetric investigation of short and intermediate-range structures and energetics of amorphous SiCO, SiCN, and SiBCN polymer-derived ceramics  

NASA Astrophysics Data System (ADS)

Polymer-derived ceramics (PDCs) are a new class of amorphous ceramics in the Si-B-C-N system that are synthesized by the pyrolysis of silicon-based organic polymers. PDCs are lightweight and are resistant to creep, crystallization, and oxidation at temperatures near 1800 K making them ideal for a variety of high temperature applications. In spite of being X-ray amorphous, these materials display structural heterogeneity at the nanometer length scale. Their structure and resulting properties can be drastically altered by the utilization of preceramic polymers with differing chemistry and architectures. Fundamental understanding of the atomic structure is critical in deciphering the structure-property relationships and ultimately in controlling their properties for specific engineering applications. The short-range atomic structure has been extensively investigated using a variety of techniques, however, the structures at length scales beyond next-nearest neighbors remained highly controversial. Here we report the results of a spectroscopic and calorimetric study of short and intermediate -range structure and energetic of SiOC and SiBCN PDCs derived from a wide variety of precursors. SiOC PDCs with different carbon contents were synthesized from polysiloxane precurors and their structures were studied using high-resolution 13C and 29Si nuclear magnetic resonance (NMR) spectroscopy. The results suggest that these PDCs consists of a continuous mass fractal backbone of corner-shared SiC xO4-x tetrahedral units with "voids" occupied by sp 2-hybridized graphitic carbon. The oxygen-rich SiCxO 4-x units are located at the interior of this backbone with a mass fractal dimension of ~ 2.5, while the carbon-rich units occupy the two-dimensional interface between the backbone and the free carbon nanodomains. Such fractal topology is expected to give rise to unusual mechanical and transport properties characteristic of fractal percolation networks. For example, elastic moduli and transport properties such as electrical conductivity and viscosity may show power-law dependence on composition near and above the percolation threshold of the SiOC network or that of the free-carbon phase. Si(B)CN PDCs with different carbon contents were synthesized by pyrolysis of poly(boro)silylcarbodiimides and poly(boro)silazane precursors and their structure and energetics were studied using multi-nuclear, one- and two- dimensional NMR spectroscopy and oxide melt solution calorimetry. The structure of the polysilylcarbodiimide-derived SiCN PDCs at lower carbon content and pyrolysis temperatures (800 oC) consists of amorphous nanodomains of sp2 carbon and silicon nitride with an interfacial bonding between N, C and Si atoms that is stabilized by the presence of hydrogen. The interfacial Si-C and N-C bonds are destroyed with concomitant hydrogen loss upon increasing the pyrolysis temperature to 1100 oC. Calorimetry results demonstrate that the mixed bonding in the interfacial regions play a key role in the thermodynamic stabilization of these PDCs. The size of the carbon domains increases with increasing carbon content until a continuous amorphous carbon matrix is formed with 55-60 wt % C. The polyborosilylcarbodiimide-derived SiBCN ceramics contain carbon and silicon nitride nanodomains with the BN domains being present predominantly at the interface. In contrast, the structure of the polyborosilazane-derived ceramics consists of significant amount of mixed bonding in the nearest-neighbor coordination environments of Si and B atoms leading to the formation of SiC xN4-x tetrahedral units and BCN2 triangular units. The interfacial region between the SiCN and C nanodomains is occupied by the BCN phase. These results demonstrate that the chemistry of the polymeric precursors exerts major influence on the microstructure and bonding in their derived ceramics.

Widgeon, Scarlett J.

404

The removal kinetics of industrial organic compounds in natural and synthetic systems  

E-print Network

VI-6. Computer listing of data for Butyraldehyde substrate unit rate curve 116 VI-7. Computer listing of data for 2-Butanone substrate unit . rate curve 118 VI-8. Computer listing of data for Butyric acid substrate . unit rate curve 120 VI-9... xvi LIST OF FIGURES, . (CONTINUED) Figure VI-7. Cal-Comp. . plot of substrate rates of formation versus time. Page YI-8. Ethanol unit rate curve. VI-9. Butyraldehyde unit rate curve. VI-10. 2-Butanone unit rate curve . YI-11. Butyric acid unit...

Petrasek, Albert Charles

2012-06-07

405

Biodegradation of Aromatic Compounds by Escherichia coli  

PubMed Central

Although Escherichia coli has long been recognized as the best-understood living organism, little was known about its abilities to use aromatic compounds as sole carbon and energy sources. This review gives an extensive overview of the current knowledge of the catabolism of aromatic compounds by E. coli. After giving a general overview of the aromatic compounds that E. coli strains encounter and mineralize in the different habitats that they colonize, we provide an up-to-date status report on the genes and proteins involved in the catabolism of such compounds, namely, several aromatic acids (phenylacetic acid, 3- and 4-hydroxyphenylacetic acid, phenylpropionic acid, 3-hydroxyphenylpropionic acid, and 3-hydroxycinnamic acid) and amines (phenylethylamine, tyramine, and dopamine). Other enzymatic activities acting on aromatic compounds in E. coli are also reviewed and evaluated. The review also reflects the present impact of genomic research and how the analysis of the whole E. coli genome reveals novel aromatic catabolic functions. Moreover, evolutionary considerations derived from sequence comparisons between the aromatic catabolic clusters of E. coli and homologous clusters from an increasing number of bacteria are also discussed. The recent progress in the understanding of the fundamentals that govern the degradation of aromatic compounds in E. coli makes this bacterium a very useful model system to decipher biochemical, genetic, evolutionary, and ecological aspects of the catabolism of such compounds. In the last part of the review, we discuss strategies and concepts to metabolically engineer E. coli to suit specific needs for biodegradation and biotransformation of aromatics and we provide several examples based on selected studies. Finally, conclusions derived from this review may serve as a lead for future research and applications. PMID:11729263

Diaz, Eduardo; Ferrandez, Abel; Prieto, Maria A.; Garcia, Jose L.

2001-01-01

406

Triaryl Pyrazoline Compound Inhibits Flavivirus RNA Replication  

PubMed Central

Triaryl pyrazoline {[5-(4-chloro-phenyl)-3-thiophen-2-yl-4,5-dihydro-pyrazol-1-yl]-phenyl-methanone} inhibits flavivirus infection in cell culture. The inhibitor was identified through high-throughput screening of a compound library using a luciferase-expressing West Nile (WN) virus infection assay. The compound inhibited an epidemic strain of WN virus without detectable cytotoxicity (a 50% effective concentration of 28 ?M and a compound concentration of ?300 ?M required to reduce 50% cell viability). Besides WN virus, the compound also inhibited other flaviviruses (dengue, yellow fever, and St. Louis encephalitis viruses), an alphavirus (Western equine encephalitis virus), a coronavirus (mouse hepatitis virus), and a rhabdovirus (vesicular stomatitis virus). However, the compound did not suppress an orthomyxovirus (influenza virus) or a retrovirus (human immunodeficiency virus type 1). Mode-of-action analyses in WN virus showed that the compound did not inhibit viral entry or virion assembly but specifically suppressed viral RNA synthesis. To examine the mechanism of inhibition of dengue virus, we developed two replicon systems for dengue type 1 virus: (i) a stable cell line that harbored replicons containing a luciferase reporter and a neomycin phosphotransferase selection marker and (ii) a luciferase-expressing replicon that could differentiate between viral translation and RNA replication. Analyses of the compound in the dengue type 1 virus replicon systems showed that it weakly suppressed viral translation but significantly inhibited viral RNA synthesis. Overall, the results demonstrate that triaryl pyrazoline exerts a broad spectrum of antiflavivirus activity through potent inhibition of viral RNA replication. This novel inhibitor could be developed for potential treatment of flavivirus infection. PMID:16569847

Puig-Basagoiti, Francesc; Tilgner, Mark; Forshey, Brett M.; Philpott, Sean M.; Espina, Noel G.; Wentworth, David E.; Goebel, Scott J.; Masters, Paul S.; Falgout, Barry; Ren, Ping; Ferguson, David M.; Shi, Pei-Yong

2006-01-01

407

OPTIMAL STOPPING FOR A COMPOUND POISSON PROCESS WITH EXPONENTIAL JUMPS  

E-print Network

OPTIMAL STOPPING FOR A COMPOUND POISSON PROCESS WITH EXPONENTIAL * *stopping problems for processes derived from a compound Poisson process with expon* *ential]), the compound Poisson process X = (Xt)t 0, is giv* *en by NtX (0

Mordecki, Ernesto

408

Using Properties to Identify Ionic and Molecular Compounds  

NSDL National Science Digital Library

An inquiry activity for students to test physical properties of several compounds to analyze data and determine if the compound is ionic or covalent. This is ideal for an introduction to ionic and molecular compound nomenclature.

Tamara Ellsworth, Parkers Prairie High School, Parkers Prairie, MN, based on a lab for pre-ap chemistry at the westlake high school website.

409

Reflectance spectroscopy of organic compounds: 1. Alkanes  

USGS Publications Warehouse

Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 /??m. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as the first in a series of papers to build a spectral database of organic compounds for use in remote sensing studies. Applications range from mapping the environment on the Earth, to the search for organic molecules and life in the solar system and throughout the. universe. We show that the spectral reflectance properties of organic compounds are rich, with major diagnostic spectral features throughout the spectral range studied. Little to no spectral change was observed as a function of temperature and only small shifts and changes in the width of absorption bands were observed between liquids and solids, making remote detection of spectral properties throughout the solar system simpler. Some high molecular weight organic compounds contain single-bonded carbon chains and have spectra similar to alkanes even ' when they fall into other families. Small spectral differences are often present allowing discrimination among some compounds, further illustrating the need to catalog spectral properties for accurate remote sensing identification with spectroscopy.

Clark, R.N.; Curchin, J.M.; Hoefen, T.M.; Swayze, G.A.

2009-01-01

410

Possible complex organic compounds on Mars.  

PubMed

It is suggested that primitive Mars had somehow similar environments as primitive Earth. If life was born on the primitive earth using organic compounds which were produced from the early Earth environment, the same types of organic compounds were also formed on primitive Mars. Such organic compounds might have been preserved on Mars still now. We are studying possible organic formation on primitive and present Mars. A gaseous mixture of CO2, CO, N2 and H2O with various mixing ratios were irradiated with high energy protons (major components of cosmic rays). Hydrogen cyanide and formaldehyde were detected among volatile products, and yellow-brown-colored water-soluble non-volatile substances were produced, which gave amino acids after acid-hydrolysis. Major part of "amino acid precursors" were not simple molecules like aminonitriles, but complex compounds which eluted earlier than free amino acids in cation-exchange HPLC. These organic compounds should be major targets in the future Mars mission. Strategy for the detection of the complex organics on Mars will be discussed. PMID:11541335

Kobayashi, K; Sato, T; Kajishima, S; Kaneko, T; Ishikawa, Y; Saito, T

1997-01-01

411

Determination of arsenic compounds in earthworms  

SciTech Connect

Earthworms and soil collected from six sites in Styria, Austria, were investigated for total arsenic concentrations by ICP-MS and for arsenic compounds by HPLC-ICP-MS. Total arsenic concentrations ranged from 3.2 to 17.9 mg/kg dry weight in the worms and from 5.0 to 79.7 mg/kg dry weight in the soil samples. There was no strict correlation between the total arsenic concentrations in the worms and soil. Arsenic compounds were extracted from soil and a freeze-dried earthworm sample with a methanol/water mixture (9:1, v/v). The extracts were evaporated to dryness, redissolved in water, and chromatographed on an anion- and a cation-exchange column. Arsenic compounds were identified by comparison of the retention times with known standards. Only traces of arsenic acid could be extracted from the soil with the methanol/water (9:1, v/v) mixture. The major arsenic compounds detected in the extracts of the earthworms were arsenous acid and arsenic acid. Arsenobetaine was present as a minor constituent, and traces of dimethylarsinic acid were also detected. Two dimethylarsinoyltribosides were also identified in the extracts by co-chromatography with standard compounds. This is the first report of the presence of dimethylarsinoylribosides in a terrestrial organism. Two other minor arsenic species were present in the extract, but their retention times did not match with the retention times of the available standards.

Geiszinger, A.; Goessler, W.; Kuehnelt, D.; Kosmus, W. [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry] [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry; Francesconi, K. [Odense Univ. (Denmark). Inst. of Biology] [Odense Univ. (Denmark). Inst. of Biology

1998-08-01

412

Solid state chalcophosphate compounds of actinide elements  

NASA Astrophysics Data System (ADS)

This work involves the exploration of ternary and quaternary compounds of the actinide chalcogenides using a Zintl ion building block approach. Zintl ions are closed shell, main-group ions that can coordinate to other elements in the compound in such a way that builds up the structure. A common Zintl ion in the chalcophosphate family is the ethane-like (P2Se6)4- anion, which has been found to bond to main group, transition metal and lanthanide elements in a variety of coordination modes. To achieve our goal of new actinide-metal Zintl phase material synthesis, we are employing a low-to-moderate temperature (300 °C-800 °C) molten salt technique. This technique utilizes low-melting binary alkali chalcogen salts like K2Se3 in combination with excess chalcogen as the oxidizing agent for the actinide metal and other main group elements to be incorporated into the final structure. This departure from conventional (high-temperature) routes to solid-state materials allows for formation and isolation of metastable phases with complex, low-dimensional structures not seen in the binary compounds. Prior to our studies, three quaternary compounds of actinide chalcophosphates were reported in the literature: K2UP3Se9, Rb4U4P4Se26 and KTh2Sb2Se6. The known ternary and quaternary chalcogen compounds of the actinides have thus far exhibited rich structural chemistry.

Briggs Piccoii, Paula M.; Hess, Ryan F.; Dorhout, Peter K.; Briggs Piccoli, Paula M.; Abney, Kent D.; Schoonover, Jon R.; Dorhout, Peter K.

2000-07-01

413

The Chemistry of Nitroxyl-Releasing Compounds  

PubMed Central

Abstract Nitroxyl (HNO) demonstrates a diverse and unique biological profile compared to nitric oxide, a redox-related compound. Although numerous studies support the use of HNO as a therapeutic agent, the inherent chemical reactivity of HNO requires the use of donor molecules. Two general chemical strategies currently exist for HNO generation from nitrogen-containing molecules: (i) the disproportionation of hydroxylamine derivatives containing good leaving groups attached to the nitrogen atom and (ii) the decomposition of nitroso compounds (X-N=O, where X represents a good leaving group). This review summarizes the synthesis and structure, the HNO-releasing mechanisms, kinetics and by-product formation, and alternative reactions of six major groups of HNO donors: Angeli's salt, Piloty's acid and its derivatives, cyanamide, diazenium diolate-derived compounds, acyl nitroso compounds, and acyloxy nitroso compounds. A large body of work exists defining these six groups of HNO donors and the overall chemistry of each donor requires consideration in light of its ability to produce HNO. The increasing interest in HNO biology and the potential of HNO-based therapeutics presents exciting opportunities to further develop HNO donors as both research tools and potential treatments. Antioxid. Redox Signal. 14, 1637–1648. PMID:21235345

DuMond, Jenna F.

2011-01-01

414

Chemotaxis of Bdellovibrio bacteriovorus toward pure compounds.  

PubMed Central

Positive chemotaxis by Bdellovibrio bacteriovorus strain UKi2 was measured for 139 compounds. Twenty-one compounds were attractants; sensitive attraction was elicited by acetate, propionate, thioacetate, malonate, cis-oxalacetate, D-glucose-6-phosphate, acetyl coenzyme A, ammonium ion, barium ion, manganous ion, and potassium ion. Several of the attractants for B. bacteriovorus strain UKi2 also were attractants to strains 6-5-S and 114; however, strains 109D and 109J were not attracted by the compounds tested. Of 33 compounds tested, 8 were repellents for B. bacteriovorus strain UKi2: n-caproate, alanine, isoleucine, leucine, phenylalanine, tyrosine, cobaltous chloride, and hydronium ion. None of the organic repellents for strain UKi2 elicited repulson from strains 114 or 109D. However, all three strains of Bdellovibrio show aerotaxis. Several compounds were tested for their effects on viability and predacious growth of B. bacteriovorus strain UKi2. No simple correlation was found between attraction or repulsion and benefit or harm to bdellovibrios. The data are consistent with the view that in nature, the greatest survival value of chemotaxis for bdellovibros may be in aerotaxis, attraction to certain inorganic ions and acetate, and repulsion by hydronium ion. PMID:500565

Straley, S C; LaMarre, A G; Lawrence, L J; Conti, S F

1979-01-01

415

Chemotaxis of Bdellovibrio bacteriovorus toward pure compounds.  

PubMed

Positive chemotaxis by Bdellovibrio bacteriovorus strain UKi2 was measured for 139 compounds. Twenty-one compounds were attractants; sensitive attraction was elicited by acetate, propionate, thioacetate, malonate, cis-oxalacetate, D-glucose-6-phosphate, acetyl coenzyme A, ammonium ion, barium ion, manganous ion, and potassium ion. Several of the attractants for B. bacteriovorus strain UKi2 also were attractants to strains 6-5-S and 114; however, strains 109D and 109J were not attracted by the compounds tested. Of 33 compounds tested, 8 were repellents for B. bacteriovorus strain UKi2: n-caproate, alanine, isoleucine, leucine, phenylalanine, tyrosine, cobaltous chloride, and hydronium ion. None of the organic repellents for strain UKi2 elicited repulson from strains 114 or 109D. However, all three strains of Bdellovibrio show aerotaxis. Several compounds were tested for their effects on viability and predacious growth of B. bacteriovorus strain UKi2. No simple correlation was found between attraction or repulsion and benefit or harm to bdellovibrios. The data are consistent with the view that in nature, the greatest survival value of chemotaxis for bdellovibros may be in aerotaxis, attraction to certain inorganic ions and acetate, and repulsion by hydronium ion. PMID:500565

Straley, S C; LaMarre, A G; Lawrence, L J; Conti, S F

1979-11-01

416

Excretion of biliary compounds during intrauterine life.  

PubMed

In adults, the hepatobiliary system, together with the kidney, constitute the main routes for the elimination of several endogenous and xenobiotic compounds into bile and urine, respectively. However, during intrauterine life the biliary route of excretion for cholephilic compounds, such as bile acids and biliary pigments, is very poor. Although very early in pregnancy the fetal liver produces bile acids, bilirubin and biliverdin, these compounds cannot be efficiently eliminated by the fetal hepatobiliary system, owing to the immaturity of the excretory machinery in the fetal liver. Therefore, the potentially harmful accumulation of cholephilic compounds in the fetus is prevented by their elimination across the placenta. Owing to the presence of detoxifying enzymes and specific transport systems at different locations of the placental barrier, such as the endothelial cells of chorionic vessels and trophoblast cells, this organ plays an important role in the hepatobiliary-like function during intrauterine life. The relevance of this excretory function in normal fetal physiology is evident in situations where high concentrations of biliary compounds are accumulated in the mother. This may result in oxidative stress and apoptosis, mainly in the placenta and fetal liver, which might affect normal fetal development and challenge the fate of the pregnancy. The present article reviews current knowledge of the mechanisms underlying the hepatobiliary function of the fetal-placental unit and the repercussions of several pathological conditions on this tandem. PMID:19230042

Macias, Rocio I R; Marin, Jose J G; Serrano, Maria A

2009-02-21

417

Possible complex organic compounds on Mars  

NASA Astrophysics Data System (ADS)

It is suggested that primitive Mars had somehow similar environments as primitive Earth. If life was born on the primitive earth using organic compounds which were produced from the early Earth environment, the same types of organic compounds were also formed on primitive Mars. Such organic compounds might have been preserved on Mars still now. We are studying possible organic formation on primitive and present Mars. A gaseous mixture of CO_2, CO, N_2 and H_2O with various mixing ratios were irradiated with high energy protons (major components of cosmic rays). Hydrogen cyanide and formaldehyde were detected among volatile products, and yellow-brown-colored water-soluble non-volatile substances were produced, which gave amino acids after acid-hydrolysis. Major part of ``amino acid precursors'' were not simple molecules like aminonitriles, but complex compounds which eluted earlier than free amino acids in cation-exchange HPLC. These organic compounds should be major targets in the future Mars mission. Strategy for the detection of the complex organics on Mars will be discussed.

Kobayashi, K.; Sato, T.; Kajishima, S.; Kaneko, T.; Ishikawa, Y.; Saito, T.

1997-05-01

418

Exploring novel bioactive compounds from marine microbes.  

PubMed

The historical paradigm of the deep ocean as a biological 'desert' has shifted to one of a 'rainforest' owing to the isolation of many novel microbes and their associated bioactive compounds. Recently, there has been an explosion of information about novel bioactive compounds that have been isolated from marine microbes in an effort to further explore the relatively untapped marine microbes and their secondary metabolites for drug discovery. The microbes are recovered and purified from the ocean by both conventional and innovative isolation methods to obtain those previously thought to be 'uncultivable'. To overcome the difficulties and limitations associated with cultivation techniques, several DNA-based molecular methods have been developed to bypass the culture-dependent bottleneck. Bioactive compounds isolated using the above strategies have not only shown importance in biotechnological and pharmaceutical applications but have also increased our understanding of the diversity of marine microbiota, ecosystem functions and the exploitable biology. PMID:15939350

Zhang, Lixin; An, Rong; Wang, Jinping; Sun, Nuo; Zhang, Si; Hu, Jiangchun; Kuai, Jun

2005-06-01

419

Dosimetry of [??Ga]-labeled compounds.  

PubMed

This review compiles and analyzes the available dosimetry data of [(68)Ga] labeled compounds. Dosimetry data are given for [(68)Ga]DOTA-NOC, TOC, TATE, and NODAGA-RGDyK. The number of PET-scans with [(68)Ga]DOTA-compounds for imaging neuroendocrine tumors is increasing because [(68)Ga] has a higher affinity to somatostatin receptors (SSTR) in comparison to comparable [(111)In]-compounds. In addition, the better image resolution of the PET images provides improved diagnostics. Despite its widespread use literature on dosimetry of [(68)Ga]-labeled radiopharmaceuticals is sparse. In some cases the description of the underlying methodology is missing or human data are gained from the extrapolation of animal experiments. More and better documented dosimetry data will further promote the use of these promising new agents. PMID:22884623

Eberlein, U; Lassmann, M

2013-06-01

420

Ultrathin, microscale epitaxial compound semiconductor solar cells  

NASA Astrophysics Data System (ADS)

Compound semiconductors offer significant advantages over silicon in photovoltaics due to their direct bandgaps, ability to form multijunction solar cells, as well as superior radiation hardness. However, costs for growth and integration of these materials have been prohibitively high, thereby limiting their large-scale implementation in terrestrial photovoltaics. Here we review materials growth and fabrication strategies that were recently developed to address many of these challenges by employing device-quality, multilayer epitaxial assemblies of compound semiconductors in the manner that enables sequential release of respective functional layers as well as reuse of the growth substrate. This new approach combined with techniques of micro-transfer printing provides a practical and cost-effective route to implement high quality compound semiconductors in terrestrial photovoltaics but also opens up new application possibilities and modes of use that have not been possible with conventional technologies.

Yoon, Jongseung

2011-06-01

421

Driving Magnetostructural Transitions in Layered Intermetallic Compounds  

NASA Astrophysics Data System (ADS)

We report the dramatic effect of applied pressure and magnetic field on the layered intermetallic compound Pr0.5Y0.5Mn2Ge2. In the absence of pressure or magnetic field this compound displays interplanar ferromagnetism at room temperature and undergoes an isostructural first order magnetic transition (FOMT) to an antiferromagnetic state below 158 K, followed by another FOMT at 50 K due to the reemergence of ferromagnetism as praseodymium orders (TCPr). The application of a magnetic field drives these two transitions towards each other, whereas the application of pressure drives them apart. Pressure also produces a giant magnetocaloric effect such that a threefold increase of the entropy change associated with the lower FOMT (at TCPr) is seen under a pressure of 7.5 kbar. First principles calculations, using density functional theory, show that this remarkable magnetic behavior derives from the strong magnetoelastic coupling of the manganese layers in this compound.

Wang, J. L.; Caron, L.; Campbell, S. J.; Kennedy, S. J.; Hofmann, M.; Cheng, Z. X.; Md Din, M. F.; Studer, A. J.; Brück, E.; Dou, S. X.

2013-05-01

422

[Phenolic compounds in branches of Tamarix rasissima].  

PubMed

To study the chemical constituents of the branches of Tamarix rasissima, repeated silica gel column chromatography, Sephadex LH-20 chromatography and recrystallization were applied for chemical constituents isolation and purification. Ten phenolic compounds were isolated from the n-BuOH fraction and their structures were elucidated by physical properties and spectra analysis such as UV, ESI-MS and NMR as monodecarboxyellagic acid (1), ellagic acid (2), 3, 3'-di-O-methylellagic acid (3), 3, 3'-di-O-methylellagic acid-4-O-beta-D-glucopyranoside (4), 3, 3'-di-O-methylellagic acid-4'-O-alpha-D-arabinfuranoside (5), ferulic acid (6), isoferulic acid (7), caffeic acid (8), 4-O-acetyl-caffeic acid (9), and 4-methyl-1, 2-benzenediol (10). All compounds except for isoferulic acid were isolated firstly from this plant except for isoferulic acid, and compounds 5, 9 and 10 were obtained from Tamarix genus for the first time. PMID:25272840

Li, Juan; Li, Wei-Qi; Zheng, Ping; Wang, Rui; Yu, Jian-Qiang; Yang, Jian-Hong; Yao, Yao

2014-06-01

423

The physics of ternary graphite intercalation compounds  

NASA Astrophysics Data System (ADS)

A critical review of the novel physical properties and physical phenomena exhibited by ternary graphite intercalation compounds (TGICs) is presented. To facilitate discussion of TGICs they are classified according to their major structural features into four specific subgroups, namely homogeneous, heterogeneous, trilayer and localized. Within each subgroup particular compounds are further characterized as donor-donor, donor-acceptor and acceptor-acceptor. The preparation methods used to synthesize the materials addressed are briefly discussed as are the relevant chemical properties. The emphasis of this review is on the physics of TGICs and in particular the consequences of low-dimensionality. We show that, unlike binary graphite intercalation compounds, TGICs can be prepared with a broad range of compositions at constant stage. This feature and the enhanced interplanar and intraplanar structural variety exhibited by TGICs have stimulated a host of investigations which have extended our understanding not only of GICs but also of low-dimensional physics in general.

Solin, S. A.; Zabel, H.

1988-03-01

424

Chemosensors for detection of nitroaromatic compounds (explosives)  

NASA Astrophysics Data System (ADS)

The key types of low-molecular-mass chemosensors for the detection of nitroaromatic compounds representing energetic substances (explosives) are analyzed. The coordination and chemical properties of these chemosensors and structural features of their complexes with nitroaromatic compounds are considered. The causes and methods for attaining high selectivity of recognition are demonstrated. The primary attention is paid to the use of low-molecular-mass chemosensors for visual detection of explosives of this class by colorimetric and photometric methods. Examples of using photo- and chemiluminescence for this purpose are described. A separate section is devoted to electrochemical methods of detection of nitroaromatic compounds. Data published from 2000 to 2014 are mainly covered. The bibliography includes 245 references.

Zyryanov, G. V.; Kopchuk, D. S.; Kovalev, I. S.; Nosova, E. V.; Rusinov, V. L.; Chupakhin, O. N.

2014-09-01

425

[The vanadium compounds: chemistry, synthesis, insulinomimetic properties].  

PubMed

The review considers the biological role of vanadium, its participation in various processes in humans and other mammals, and the anti-diabetic effect of its compounds. Vanadium salts have persistent hypoglycemic and antihyperlipidemic effects and reduce the probability of secondary complications in animals with experimental diabetes. The review contains a detailed description of all major synthesized vanadium complexes having antidiabetic activity. Currently, vanadium complexes with organic ligands are more effective and safer than the inorganic salts. Despite the proven efficacy of these compounds as the anti-diabetic agents in animal models, only one organic complex of vanadium is currently under the second phase of clinical trials. All of the considered data suggest that vanadium compound are a new promising class of drugs in modern pharmacotherapy of diabetes. PMID:25249525

Fedorova, E V; Buriakina, A V; Vorob'eva, N M; Baranova, N I

2014-01-01

426

Catalyst for Oxidation of Volatile Organic Compounds  

NASA Technical Reports Server (NTRS)

Disclosed is a process for oxidizing volatile organic compounds to carbon dioxide and water with the minimal addition of energy. A mixture of the volatile organic compound and an oxidizing agent (e.g. ambient air containing the volatile organic compound) is exposed to a catalyst which includes a noble metal dispersed on a metal oxide which possesses more than one oxidation state. Especially good results are obtained when the noble metal is platinum, and the metal oxide which possesses more than one oxidation state is tin oxide. A promoter (i.e., a small amount of an oxide of a transition series metal) may be used in association with the tin oxide to provide very beneficial results.

Wood, George M. (Inventor); Upchurch, Billy T. (Inventor); Schryer, David R. (Inventor); Davis, Patricia P. (Inventor); Kielin, Erik J. (Inventor); Brown, Kenneth G. (Inventor); Schyryer, Jacqueline L. (Inventor); DAmbrosia, Christine M. (Inventor)

2000-01-01

427

Oxidative electrochemical switching of photochromic diarylethene compounds  

NASA Astrophysics Data System (ADS)

A series of photochromic diarylethenes compounds were synthesized and the electrochemistry and electrochemistry reaction mechanism properties were investigated. The cyclic voltammetry tests demonstrated that the colorless open-ring isomers were assigned to the unique oxidation process, but the color closed-ring isomers of these compounds were assigned to two oxidation processes. In addition, the electrochromism of diarylethene compound is observed in solution: The closed-ring reaction can be triggered by electrochemical oxidation, while the open-ring reaction must be photochemically driven. These oxidation processes properties can be useful as the oxidation processes electrochemical switching and the oxidation electrochemical switching properties of these different diarylethene isomers can be potential for electrochemistry data storages.

Fan, Congbin; Pu, Shouzhi; Liu, Weijun; Yang, Tianshe; Liu, Gang

2008-12-01

428

Toxic organic compounds from energy production  

SciTech Connect

The US Department of Energy's Office of Health and Environmental Research (OHER) has supported work in our laboratory since 1977. The general theme of this program has been the identification of potentially toxic organic compounds associated with various combustion effluents, following the fates of these compounds in the environment, and improving the analytical methodology for making these measurements. The projects currently investigation include: an improved sampler for semi-volatile compounds in the atmosphere; the wet and dry deposition of dioxins and furans from the atmosphere; the photodegradation and mobile sources of dioxins and furans; and the bioaccumulation of PAH by tree bark. These projects are all responsive to OHER's interest in the pathways and mechanisms by which energy-related agents move through and are modified by the atmosphere''. The projects on gas chromatographic and liquid chromatographic tandem mass spectrometry are both responsive to OHER's interest in new and more sensitive technologies for chemical measurements''. 35 refs., 9 figs.

Hites, R.A.

1991-09-20

429

Photoinduced mass transport in azo compounds  

NASA Astrophysics Data System (ADS)

The photoinduced changes of optical properties in azobenzene containing compound thin films were studied under influence of polarized and non-polarized 532 nm laser light. Under influence of light azo compounds experience trans-cis isomerisation process, that can be observed in the absorbance spectrum of the sample. If the light is linearly polarized, molecules align perpendicularly to the electric field vector and as a result photoinduced dichroism and birefringence is obtained. If a known lateral polarization modulation of the light beam is present, mass transport of the azobenzene containing compound occurs. By measuring the surface relief with a profilometer the direction of mass transport can be determined. The studies of this work show that direct holographic recording of surface relief gratings can be used in optoelectronics, telecommunications and data storage.

Klismeta, K.; Teteris, J.; Aleksejeva, J.

2013-12-01

430

Origin of organic compounds in carbonaceous chondrites  

NASA Astrophysics Data System (ADS)

Carbonaceous chondrites, a class of primitive meteorite, have long been known to contain their complement of carbon largely in the form of organic, i.e., hydrocarbon-related, matter. Both discrete organic compounds and an insoluble, macromolecular material are present. Several characteristics of these materials provide evidence for their abiotic origin. The principal formation hypothesis have invoked chemistry occurring either in the solar nebula or on the parent body. However, recent stable isotope analyses of the meteorite carboxylic acids and amino acids indicate that they may be related to interstellar cloud compounds. These results suggest a formation scheme in which interstellar compounds were incorporated into the parent body and subsequently converted to the present suite of meteorite organics by the hydrothermal process believed to have formed the clay minerals of the meteorite matrix.

Cronin, J. R.

431

Pharmacy compounding primer for physicians: prescriber beware.  

PubMed

Since the development of federal standards for drug approval, the practice of medicine has historically involved the compounding of medications based on a physician's determination that a US FDA-approved product either did not exist, or could not be used for medical reasons. Today, prescriptions for non-FDA-approved compounded drugs may be driven by fanciful and largely unregulated pharmacy advertisements to physicians and patients and/or payer reimbursement policies, thus placing prescribers in the backseat for clinical decision making. This article outlines essential differences between FDA-approved drugs and compounded drugs and reasserts the primary medical role of physicians for determining what medical circumstances may necessitate treatment with non-FDA-approved products. In addition, liability concerns when prescribing non-FDA-approved drugs are discussed. While representing a US perspective, underlying principles apply globally in the setting of magistral and extemporaneous formulations produced outside national regulatory frameworks. PMID:23039281

Sellers, Sarah; Utian, Wulf H

2012-11-12

432

Antiviral lead compounds from marine sponges.  

PubMed

Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hoped to be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed. PMID:21116410

Sagar, Sunil; Kaur, Mandeep; Minneman, Kenneth P

2010-01-01

433

Antiviral Lead Compounds from Marine Sponges  

PubMed Central

Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hopedto be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed. PMID:21116410

Sagar, Sunil; Kaur, Mandeep; Minneman, Kenneth P.

2010-01-01

434

Electronic structures of Laves phase compounds  

NASA Astrophysics Data System (ADS)

The electronic structures of Laves phase compounds AB 2 (A = Y, Zr, Nb; B = Cr, Mn, Co, Ni) were investigated systematically by the LMTO method within the framework of the LSD approximation. Comparing the calculated total energy for hypothetical para-, ferro-, and antiferromagnetic state with the C14 and the C15 structure, the theoretical predictions are in good agreement with the experiments concerning the stability of the crystal structure and the magnetism. The magnetic stability critically depends upon the change of the lattice spacing, which leads to the colorful behaviors of the magnetism in Fe Laves phase compounds and the anomalous volume change in the antiferromagnetic state of YMn 2.

Asano, Setsuro; Ishida, Shoji

1987-12-01

435

Organic photosensitive devices using subphthalocyanine compounds  

DOEpatents

An organic photosensitive optoelectronic device, having a donor-acceptor heterojunction of a donor-like material and an acceptor-like material and methods of making such devices is provided. At least one of the donor-like material and the acceptor-like material includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound; and/or the device optionally has at least one of a blocking layer or a charge transport layer, where the blocking layer and/or the charge transport layer includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound.

Rand, Barry (Princeton, NJ); Forrest, Stephen R. (Ann Arbor, MI); Mutolo, Kristin L. (Hollywood, CA); Mayo, Elizabeth (Alhambra, CA); Thompson, Mark E. (Anaheim Hills, CA)

2011-07-05

436

Dry etching method for compound semiconductors  

DOEpatents

A dry etching method is disclosed. According to the present invention, a gaseous plasma comprising, at least in part, boron trichloride, methane, and hydrogen may be used for dry etching of a compound semiconductor material containing layers including aluminum, or indium, or both. Material layers of a compound semiconductor alloy such as AlGaInP or the like may be anisotropically etched for forming electronic devices including field-effect transistors and heterojunction bipolar transistors and for forming photonic devices including vertical-cavity surface-emitting lasers, edge-emitting lasers, and reflectance modulators. 1 fig.

Shul, R.J.; Constantine, C.

1997-04-29

437

Antifungal Activity of Isothiocyanates and Related Compounds  

PubMed Central

This paper presents the results of a study on the antifungal activity of isothiocyanates—derivatives of biphenyl (group “A”), of stilbene (“B”), of azobenzene and benzeneazonaphthalene (“C”), of naphthalene (“D”), and of further polycondensed aromatic hydrocarbons (“E”). From a total of 48 investigated compounds, antifungal activity was observed only in A and D group compounds. B, C, and E group derivatives are extremely insoluble in water, and the molecules are very large; as a result, they probably cannot pass into spores or mycelium of fungi. Thus, the —NCS group cannot manifest its reactivity. PMID:5647516

Drobnica, L.; Zemanova, M.; Nemec, P.; Antos, K.; Kristian, P.; Martvon, A.; Zavodska, E.

1968-01-01

438

Antifungal Activity of Isothiocyanates and Related Compounds  

PubMed Central

Data are presented concerning the antifungal activity of 11 natural isothiocyanates and 27 synthetized analogues in Aspergillus niger, Penicillium cyclopium, and Rhizopus oryzae, as well as in 13 additional saprophytic and parasitic fungi. A remarkable antifungal activity was observed in some analogues of benzylisothiocyanate and ?-phenylethylisothiocyanate. The latter-mentioned compounds have not been described previously. In the group of benzylisothiocyanates, a correlation, which was inversely proportional, was detected between ed100 values for A. niger and R. oryzae and the corresponding molar solubilities of compounds in water. In contradistinction, no relationship was observed between antifungal activity and chemical reactivity of investigated derivatives. PMID:6049294

Drobnica, L.; Zemanova, M.; Nemec, P.; Antos, K.; Kristian, P.; Stullerova, A.; Knoppova, V.; Nemec, P.

1967-01-01

439

Photochemistry and Photophysics of Coordination Compounds: Copper  

Microsoft Academic Search

Cu(I) complexes and clusters are the largest class of compounds of relevant photochemical and photophysical\\u000a interest based on a relatively abundant metal element. Interestingly, Nature has given an essential\\u000a role to copper compounds in some biological systems, relying on their kinetic lability and versatile coordination\\u000a environment. Some basic properties of Cu(I) and Cu(II) such as their coordination geometries and electronic\\u000a levels

Nicola Armaroli; Gianluca Accorsi; François Cardinali; Andrea Listorti

440

Beta cell device using icosahedral boride compounds  

DOEpatents

A beta cell for converting beta-particle energies into electrical energy having a semiconductor junction that incorporates an icosahedral boride compound selected from B.sub.12 As.sub.2, B.sub.12 P.sub.2, elemental boron having an .alpha.-rhombohedral structure, elemental boron having a .beta.-rhombohedral structure, and boron carbides of the chemical formula B.sub.12-x C.sub.3-x, where 0.15compound self-heals, resisting degradation from radiation damage.

Aselage, Terrence L. (62 Avenida Del Sol, Cedar Crest, NM 87008); Emin, David (1502 Harvard Ct., NE., Albuquerque, NM 87106-3712)

2002-01-01

441

Process for producing phenolic compounds from lignins  

DOEpatents

A process is described for the production of low molecular weight phenolic compounds from lignins through the pyrolysis of the lignins in the presence of a strong base. In a preferred embodiment, potassium hydroxide is present in an amount of from about 0.1% to about 5% by weight, the pyrolysis temperature is from about 400 C to about 600 C at atmospheric pressure, and the time period for substantial completion of the reaction is from about 1--3 minutes. Examples of low molecular weight phenolic compounds produced include methoxyphenols, non-methoxylated phenols, and mixtures thereof. 16 figs.

Agblevor, F.A.

1998-09-15

442

Magnetic Properties of Some Divalent Europium Compounds  

Microsoft Academic Search

The compounds of divalent europium form an attractive series for magnetic investigations because the magnetic ions are in S states and the crystal structures are generally simple. Moreover, true ferromagnetism, which is quite unusual in compounds, has been observed in EuO by Matthias, Bozorth, and Van Vleck.We have prepared samples of EuS, EuSe, EuTe, EuCO3, EuTiO3, EuZrO3, EuSO4, and EuCl2,

T. R. McGuire; B. E. Argyle; M. W. Shafer; J. S. Smart

1963-01-01

443

Basics of sterile compounding: bubble point testing.  

PubMed

Compounding pharmacies that compound sterile preparations must choose sterile filters that are approved for human use. They may rely on the filter manufacturer's Certificate of Quality to ensure the sterile filter is pyrogen free and has been tested for bacterial retention. The Certificate of Quality from the filter manufacturer also contains other useful information about the filter such as: flow rate and maximum pressure drop, thermal and hydraulic stress, and membrane results of the initial integrity test performed on the filter membrane with water, if a hydrophilic membrane. This article discusses the integrity test, which is often called the water bubble point test. PMID:24881342

Thoma, Laura

2014-01-01

444

Quality of Extemporaneously Compounded Nitroglycerin Ointment  

Microsoft Academic Search

\\u000a Purpose  Published clinical trials support the use of 0.2 to 0.4 percent nitroglycerin ointment for the treatment of an anal fissure,\\u000a although no product is yet available in the United States. In 2004, 84,000 prescriptions were written for compounded nitroglycerin\\u000a ointment. This study was designed to evaluate the quality of extemporaneously compounded nitroglycerin ointment.\\u000a \\u000a \\u000a \\u000a Methods  Prescriptions for 0.3 percent nitroglycerin ointment were

Daniel L. Azarnoff; J. C. Lee; Charles Lee; John Chandler; David Karlin

2007-01-01

445

Thin film Heusler compounds manganese nickel gallium  

NASA Astrophysics Data System (ADS)

Multiferroic Heusler compounds Mn3--xNi xGa (x=0,1,2) have a tetragonal unit cell that can variously be used for magneto-mechanically coupled shape memory ( x=1,2) and spin-mechanical applications (x=0). The first fabrication of fully epitaxial thin films of these and electronically related compounds by sputtering is discussed. Traditional and custom lab characterization of the magnetic and temperature driven multiferroic behavior is augmented by more detailed synchrotron-based high energy photoemission spectroscopic techniques to describe the atomic and electronic structure. Integration of the MnNi2Ga magnetic shape memory compound in microwave patch antennas and active free-standing structures represents a fraction of the available and promising applications for these compounds. Prototype magnetic tunnel junctions are demonstrated by Mn3Ga electrodes with perpendicular anisotropy for spin torque transfer memory structures. The main body of the work concentrates on the definition and exploration of the material series Mn3--xNi xGa (x=0,1,2) and the relevant multiferroic phenomena exhibited as a function of preparation and external stimuli. Engineering results on each x=0,1,2 are presented with device prototypes where relevant. In the appendices the process of the materials design undertaken with the goal of developing new ternary intermetallics with enhanced properties is presented with a full exploration of the road from band structure calculations to device implementation. Cobalt based compounds in single crystal and nanoparticle form are fabricated with an eye to developing the production methods for new cobalt- and iron-based magnetic shape memory compounds for device applications in different forms. Mn2CoSn, a compound isolectronic and with similar atomic ordering to Mn2NiGa is experimentally determined to be a nearly half-metallic ferromagnet in contrast to the metallic ferrimagnetism in the parent compound. High energy photoemission spectroscopy is shown to be applicable to the analysis and observation of deeply buried metallic and semiconducting interface in an analysis of chalcopyrite solar cell heterolayers and model magnetic tunnel junctions with half-metalic Heusler electrodes.

Jenkins, Catherine Ann

446

Chemical bonding in titanium-metalloid compounds  

Microsoft Academic Search

First-principles molecular-orbital calculations for titanium-metalloid compounds TiB, TiB2, TiC, Ti2N, TiN, TiO, TiO2, TiSi, TiSi2, TiP, TiS, and TiS2 have been made by the use of discrete-variational Xalpha method with model clusters composed of about 100 atoms. In order to compare the covalent bonding quantitatively among these compounds with different crystal structures, we used covalent bond density in which both

Masataka Mizuno; Isao Tanaka; Hirohiko Adachi

1999-01-01

447

Some convolution theorems for compound poisson processes  

Microsoft Academic Search

Previously the term compound Poisson processes in the wide sense (cPp i. w. s.) has by the present author in several papers (e.g. 1964) been used for a process for which the probability of the occurrence of m changes in the interval (0, ?) on the absolute parameter scale, is defined by the following relation: where s and t are

Carl Philipson

1967-01-01

448

On definition of compound poisson processes  

Microsoft Academic Search

Some authors define the (elementary) compound Poisson process in wide sense {?t, 0 ? t < ?} with help of probability distributions where ? is a so-called operational time, a continuous non-decreasing function of t vanishing for t = 0, and V(q, t) is a non-negative distribution function for every t.

Erkki Pesonen

1968-01-01

449

Exit problems for oscillating compound Poisson process  

Microsoft Academic Search

In this article we determine the Laplace transforms of the main boundary functionals of the oscillating compound Poisson process. These are the first passage time of the level, the joint distribution of the first exit time from the interval and the value of the overshoot through the boundary. Under certain conditions we establish the asymptotic behaviour of the mentioned functionals.

Tetyana Kadankova

2011-01-01

450

Pyrolysis of wood-based polymer compounds  

Microsoft Academic Search

Due to increasing costs of synthetic polymers or plastics, which are directly correlated with the oil and gas prices, natural polymers with similar properties are becoming more and more interesting. One such product is a commercially available wood-based compound Arboform® composed largely of lignin and cellulose. From these two materials, lignin is largely a byproduct of the paper industry, and

Thomas Haensel; Andreas Comouth; Nicolas Zydziak; Eva Bosch; Axel Kauffmann; Juergen Pfitzer; Stefan Krischok; Juergen A. Schaefer; Syed Imad-Uddin Ahmed

2010-01-01

451

Catalytic Destruction Of Toxic Organic Compounds  

NASA Technical Reports Server (NTRS)

Proposed process disposes of toxic organic compounds in contaminated soil or carbon beds safely and efficiently. Oxidizes toxic materials without producing such other contaminants as nitrogen oxides. Using air, fuel, catalysts, and steam, system consumes less fuel and energy than decontamination processes currently in use. Similar process regenerates carbon beds used in water-treatment plants.

Voecks, Gerald E.

1990-01-01

452

Compound nucleus studies withy reverse kinematics  

SciTech Connect

Reverse kinematics reactions are used to demonstrate the compound nucleus origin of intermediate mass particles at low energies and the extension of the same mechanism at higher energies. No evidence has appeared in our energy range for liquid-vapor equilibrium or cold fragmentation mechanisms. 11 refs., 12 figs.

Moretto, L.G.

1985-06-01

453

Visualizing Compound Rotations with Virtual Reality  

ERIC Educational Resources Information Center

Mental rotations are among the most difficult of all spatial tasks to perform, and even those with high levels of spatial ability can struggle to visualize the result of compound rotations. This pilot study investigates the use of the virtual reality-based Rotation Tool, created using the Virtual Reality Modeling Language (VRML) together with…

Flanders, Megan; Kavanagh, Richard C.

2013-01-01

454

Extraction chemistry of some bidentate organophosphorus compounds  

Microsoft Academic Search

The extraction chemistry of methylenediphosphonates, carbamoylphosphonates, and carbamoylmethylenephosphonates has been investigated. The bidentate organophosphorus compounds extract actinides strongly, extract lanthanides, iron, gallium, molybdenum, titanium, vanadium, and zirconium partially, and do not extract most other elements from 5 to 7 M nitric acid. The properties of the extractants and extraction mechanisms are discussed. The effect of complexing agents on the extraction

L. L. Martella; J. D. Navratil; W. F. Santiago

1978-01-01

455

Fungal Endophthalmitis Associated with Compounded Products  

PubMed Central

Fungal endophthalmitis is a rare but serious infection. In March 2012, several cases of probable and laboratory-confirmed fungal endophthalmitis occurring after invasive ocular procedures were reported nationwide. We identified 47 cases in 9 states: 21 patients had been exposed to the intraocular dye Brilliant Blue G (BBG) during retinal surgery, and the other 26 had received an intravitreal injection containing triamcinolone acetonide. Both drugs were produced by Franck’s Compounding Lab (Ocala, FL, USA). Fusarium incarnatum-equiseti species complex mold was identified in specimens from BBG-exposed case-patients and an unopened BBG vial. Bipolaris hawaiiensis mold was identified in specimens from triamcinolone-exposed case-patients. Exposure to either product was the only factor associated with case status. Of 40 case-patients for whom data were available, 39 (98%) lost vision. These concurrent outbreaks, associated with 1 compounding pharmacy, resulted in a product recall. Ensuring safety and integrity of compounded medications is critical for preventing further outbreaks associated with compounded products. PMID:24447640

Mikosz, Christina A.; Smith, Rachel M.; Kim, Moon; Tyson, Clara; Lee, Ellen H.; Adams, Eleanor; Straif-Bourgeois, Susanne; Sowadsky, Rick; Arroyo, Shannon; Grant-Greene, Yoran; Duran, Julie; Vasquez, Yvonne; Robinson, Byron F.; Harris, Julie R.; Lockhart, Shawn R.; Torok, Thomas J.; Mascola, Laurene

2014-01-01

456

A compilation of bioactive compounds from Ayurveda  

Microsoft Academic Search

This review deals with the key bioactive compounds and the role of medicinal plants in Ayurvedic systems of medicine in India and their earlier investigation. There has been an increase in demand for the Phytopharmaceutical products of Ayurveda in Western countries, because of the fact that the allopathic drugs have more side effects. Many pharmaceutical companies are now concentrating on

Ramar Perumal Samy; Peter Natesan Pushparaj; Ponnampalam Gopalakrishnakone

457

Compound exocytosis of granules in human neutrophils  

Microsoft Academic Search

Human neutrophils are of prime impor- tance for the immune defense. Recent data from eosinophils and pancreatic beta cells have indi- cated that granules, upon exocytosis, occasionally fuse with each other in the cytosol prior to their subsequent fusion with the plasma membrane. This is termed compound exocytosis. We therefore studied exocytosis of single granules from human neutrophils by the

Karsten Lollike; Manfred Lindau; Jero Calafat; Niels Borregaard

2002-01-01

458

Temperature dependent XRD Investigations on Heusler Compounds  

Microsoft Academic Search

Most of the X2YZ Heusler compounds used for the produc- tion of TMR devices are based on 3d transition metals like Co for the X element and Cr, Mn, Fe, or mixtures of those for the Y element. The main group element (Z) is usually taken from the 3 rd row (Al, Si) or from the 4 th row (Ga,

B. Balke; G. H. Fecher; Johannes Gutenberg; Universitaet Mainz

2006-01-01

459

Cleavage of ?-dicarbonyl compounds by terpene hydroperoxide.  

PubMed

The highly reactive ?-dicarbonyl compounds, glyoxal, methylglyoxal (MGO), and 3-deoxyglucosone, react with the amino groups of proteins to form advanced glycation end-products (AGEs) which have been implicated in diabetic complications, aging, and Alzheimer's disease. We found that a test sample of terpinen-4-ol (T4) containing hydroperoxides showed cleaving activity toward an ?-dicarbonyl compound, but that the freshly isolated pure sample did not. Prepared terpinen-4-ol hydroperoxide (T4-H) also e