WorldWideScience

Sample records for karl fischer titration

  1. Reference test methods for total water in lint cotton by Karl Fischer Titration and low temperature distillation

    Science.gov (United States)

    In a study of comparability of total water contents (%) of conditioned cottons by Karl Fischer Titration (KFT) and Low Temperature Distillation (LTD) reference methods, we demonstrated a match of averaged results based on a large number of replications and weighing the test specimens at the same tim...

  2. Investigation of amine-buffered amide reagents for coulometric Karl Fischer titration.

    Science.gov (United States)

    Larsson, William; Cedergren, Anders

    2009-06-15

    Formamide (FA), N-methylformamide (NMF), and dimethylformamide (DMF), were evaluated as solvents for coulometric Karl Fischer (KF) reagents in combination with several amine bases. Except for the effect of the iodine species (iodine or triiodide), the pH of the reagent and the position of the sulfur dioxide/hydrogen sulfite equilibrium were found to be the main factors explaining the large difference in the observed reaction rates between water and the KF reagent in these solvents. Acid-base titrations showed that hydrogen sulfite is the main sulfur reactant in these media. The results will be of great importance in finding suitable combinations of base and solvent with respect to stoichiometry, side reactions caused by active carbonyl compounds, and reagent stability.

  3. Water determination in iron oxyhydroxides and iron ores by Karl Fischer titration

    Science.gov (United States)

    da Cunha, Camila C. R. F.; da Costa, Geraldo M.

    2016-08-01

    Protohematite (Fe2-x/3(OH) x O3-x 1 ≤ x hydroxyl groups in their structures. These species were described in prior studies mainly with the aid of X-ray diffraction and Infrared spectroscopy. The existence of these phases in soils might have influence in redox processes, and they were considered as a possible water reservoir in Martian soils. In this study, we have used for the first time the Karl Fischer titration method to determine the amount of water released after heating several synthetic samples of goethite, hematite and natural iron ores at 105, 400, 600 and 900 °C. It was found that heating at 105 °C did not remove all moisture from the samples, and higher temperatures were necessary to completely remove all the absorbed water. The water contents determined at 400, 600 and 900 °C were found to be the same within the experimental errors, suggesting the inexistence of both protohematite and hydrohematite in the investigated samples. Therefore, the above-mentioned effects of these phases in soils might have to be reevaluated.

  4. Coulometric Karl Fischer titration of trace water in diaphragm-free cells.

    Science.gov (United States)

    Larsson, William; Cedergren, Anders

    2005-03-15

    Factors influencing the accuracy and precision for diaphragm-free Karl Fischer coulometric determinations of low mug-amounts of water have been studied using the Metrohm 756 (pulsed current) coulometer and eight different types of commercial coulometric reagents and some modifications of these. As in the case of diaphragm-free coulometric titration of large amounts of water, the positive errors, due to the formation of oxidizable reduction products (of sulfur dioxide) in the cathode reaction (besides hydrogen), were found to be minimized by the use of highest possible pulse current (in the range 100-400mA) in combination with the fastest possible titration rate. Most accurate (102-103%) and precise results (typical relative standard deviation 1.8%) were obtained for reagents containing very large concentrations of imidazole in combination with the presence of modifiers like hexanol, chloroform and propylene glycol (i.e. the HYDRA-POINT reagents). Similar results were obtained when this type of reagent was mixed 60/40 with xylene according to the ASTM recommendation for water determinations in petroleum products like crude and lubricating oils. Addition of decanol to this type of reagent mixture was found to reduce the influence from the oxidative reduction products significantly. A reduction of the error from 3.6% relative to 1.6% was achieved by addition of 9% (v/v) of decanol to a 60/40 reagent mixture of HYDRA-POINT Coulometric Gen (containing hexanol as modifier) and xylene. For larger concentrations of decanol the pulse current had to be lowered to 100mA and this might explain why no further improvement was observed. An additional attempt to minimize the interference by lowering the concentration of sulfur dioxide in the reagents gave no significant effect. However, by means of a home-built computer-controlled coulometric instrumentation based on continuous instead of pulsed current (including a large cathodic current density) it was possible to achieve

  5. Differentiation of rye and wheat flour as well as mixtures by using the kinetics of Karl Fischer water titration.

    Science.gov (United States)

    Hădărugă, Daniel I; Costescu, Corina I; Corpaş, Laura; Hădărugă, Nicoleta G; Isengard, Heinz-Dieter

    2016-03-15

    The aim of this study was to find a simple way to differentiate between rye and wheat flour and their mixtures by using the kinetic parameters of Karl Fischer water titration (KFT). Consequently, the water content and type of molecules in rye and wheat mixtures used in Romanian bread making have been investigated by means of volumetric KFT. Further, the kinetics of KFT have been determined and novel kinetic parameters corresponding to "surface" and "strongly-retained" water molecules have been identified to discriminate between rye and wheat flour and their mixtures. The "surface" and "strongly-retained" water reaction rates well correlate with the rye content in the flour mixtures, especially at higher temperature analysis (r>0.95). These parameters can be used as indicators for quality evaluation of such type of mixtures, as well as to identify adulteration by improper use of the rye-wheat flour ratios in bread making.

  6. Diaphragm-free cell for trace determination of water based on the karl Fischer reaction using continuous coulometric titration.

    Science.gov (United States)

    Cedergren, A; Jonsson, S

    1997-08-01

    A new type of diaphragm-free coulometric cell for continuous coulometric Karl Fischer titrations of water in the range 0.1-1000 μg is described. The relative standard deviation obtained for titrations of 1 μg amounts of water was typically 1%. The background due to diffusion of water from the air was normally in the range 0.3-0.9 μg of water min(-1) depending on environmental humidity. The variation in the background was normally ±0.01 μg min(-1). The construction makes it possible, at any time in a sequence of titrations, to renew the catholyte by means of a Teflon plunger inside the cathode compartment. In this way, the interference effects caused by oxidizable reduction products of methyl sulfite which are formed at the cathode can be controlled in a very simple way. These products are rapidly eliminated by means of a normal titration before a new titration starts. The need for this draining step differs depending on the type of reagent used. The coulometric titration system makes use of true potentiometric end-point detection, and this principle makes it possible to control the iodine level at the end-point at much lower levels as compared with commercial instrumentation. The analytical advantages gained by this option are demonstrated for the determination of water in ethylenediamine, a task which was found to be impossible when using end-point concentrations in the range (3-7) × 10(-5) M, which is typical for the bipotentiometric indicating system used in commercial instruments. Recovery rates in the range 100-102% were obtained and are shown to be dependent on the type of reagent used. The most accurate results were obtained for an imidazole-buffered methanolic reagent in which the concentration of sulfur dioxide was kept relatively low (0.10 M). The diaphragm-free cell described was shown to be compatible with all of the commercial reagents (designed for coulometry) investigated, including the well-known Hydranal products Coulomat A, AK, AG, AG-H, and

  7. Interference-free coulometric titration of water in lithium bis(oxalato)borate using Karl Fischer reagents based on N-methylformamide.

    Science.gov (United States)

    Larsson, William; Panitz, Jan-Christoph; Cedergren, Anders

    2006-03-15

    A non-alcoholic coulometric reagent based on N-methylformamide (NMF) was shown to eliminate the severe interference effect caused by the alcohol component of the conventional Karl Fischer (KF) reagent on the battery electrolyte lithium bis(oxalato)borate (LiBOB). For sample amounts up to 240 microg of water, the stoichiometry of the KF reaction deviated only slightly from the ideal 1:1 ratio for the best reagent composition. Both solid and dissolved (in acetonitrile, tetrahydrofuran (THF), and ethylene carbonate/ethyl methyl carbonate) LiBOB were titrated successfully using a Metrohm 756 KF Coulometer with a diaphragm cell. The detection limit was estimated to be 0.5-1 microg of water using 100ml of reagent in this system.

  8. Determination of the analytical performance of a headspace capillary gas chromatographic technique and karl Fischer coulometric titration by system calibration using oil samples containing known amounts of moisture.

    Science.gov (United States)

    Jalbert, J; Gilbert, R; Tétreault, P

    1999-08-01

    Over the past few years, concerns have been raised in the literature about the accuracy of the Karl Fischer (KF) method for assessing moisture in transformer mineral oils. To better understand this issue, the performance of a static headspace capillary gas chromatographic (HS-CGC) technique was compared to that of KF coulometric titration by analyzing moisture in samples containing known amounts of water and various samples obtained from the National Institute of Standards and Technology (NIST). Two modes of adding samples into the KF vessel were used:  direct injection and indirect injection via an azeotropic distillation of the moisture with toluene. Under the conditions used for direct injection, the oil matrix was totally dissolved in the anolyte, which allowed the moisture to be titrated in a single-phase solution rather than in a suspension. The results have shown that when HS-CGC and combined azeotropic distillation/KF titration are calibrated with moisture-in-oil standards, a linear relation is observed over 0-60 ppm H(2)O with a correlation coefficient better than 0.9994 (95% confidence), with the regression line crossing through zero. A similar relation can also be observed when calibration is achieved by direct KF addition of standards prepared with octanol-1, but in this case an intercept of 4-5 ppm is noted. The amount of moisture determined by curve interpolation in NIST reference materials by the three calibrated systems ranges from 13.0 to 14.8 ppm for RM 8506 and 42.5 to 46.4 ppm for RM 8507, and in any case, the results were as high as those reported in the literature with volumetric KF titration. However, titration of various dehydrated oil and solvent samples showed that direct KF titration is affected by a small bias when samples contain very little moisture. The source of error after correction for the large sample volume used for the determination (8 mL) is about 6 ppm for Voltesso naphthenic oil and 4 ppm for toluene, revealing a matrix

  9. Coulometric determination of trace water in active carbonyl compounds using modified Karl Fischer reagents

    Energy Technology Data Exchange (ETDEWEB)

    Nordin-Andersson, I.; Cedergren, A.

    1987-03-01

    Improved conditions for the coulometric determination of trace water in samples containing potentially interfering substances like aldehydes and ketones were obtained by using a formamide-based, rapidly reacting Karl Fischer reagent in which methanol was replaced by 2-methoxyethanol. The shape of the potentiometric titration curves obtained by titrating spent Karl Fischer reagents with iodine indicates a less degree of triiodide formation in the presence of formamide. The corresponding increase in iodine results in a more rapid overall reaction rate since the reaction involving iodine is much more rapid than that with triiodide. For water amounts corresponding to less than 0.1% the stoichiometry of the Karl Fischer reaction was found to be 1:1, relatively independent of the concentration of 2-methoxyethanol. For larger amounts of water this stoichiometric ratio was attained by using a reagent containing 2-methoxyethanol/formamide 80/20 (v/v), 0.6 M imidazole, and 0.4 M sulfur dioxide.

  10. Urea as the basic component in pyridine-free Karl Fischer reagent

    NARCIS (Netherlands)

    Bos, M.

    1984-01-01

    A solution of urea, sulphur dioxide and sodium salicylate in methanol is proposed as the solvent in the Karl Fischer titration, with a separate iodine solution as titrant. Comparison of the performance of this solvent with that of some commercial reagents shows that it is has distinct advantages for

  11. Reaction rates between water and the Karl Fischer reagent.

    Science.gov (United States)

    Cedergren, A

    1974-04-01

    Reaction rates between water and the Karl Fischer reagent have been determined by potentiometric measurement for various compositions of the Karl Fischer reagent. The study has been made with an iodine complex concentration of 0.3-1.2 mM and sulphur dioxide complex at 0.01-0.5M. The concentration of excess of pyridine had no measurable effect on the rate of the main reaction. The reaction was found to be first-order with respect to iodine complex, to sulphur dioxide complex, and to water. The rate constant was (1.2+/-0.2) x 10(3) 1(2). mole(-2). sec(-1). In an ordinary titration it is therefore essential to keep the sulphur dioxide concentration high for the reaction to go to completion within a reasonable time. The extent of side-reactions was found to be independent of the iodine concentration at low concentrations. The side-reactions increased somewhat with increasing sulphur dioxide pyridine concentrations and decreased to about 60% when the temperature was lowered from 24 degrees to 7 degrees.

  12. Progress in Karl Fischer coulometry using diaphragm-free cells.

    Science.gov (United States)

    Cedergren, A; Jonsson, S

    2001-11-15

    Different designs of a semiopen, drainable cathode compartment of a medium-sized coulometric Karl Fischer (KF) cell for the determination of water in the range 0.1-500 microg were evaluated. The main criterion for the design was to keep the resistance between the anolyte and catholyte low enough to permit the generation of currents larger than 20 mA (for an output voltage of 28 V). It was found that a good compromise between the size of this current and a minimal influence from diffusing/migrating oxidizable reduction products from the catholyte was achieved by means of an interface having a channel length and diameter of 8 and 2.1 mm, respectively (catholyte volume, approximately 1 mL). To show the general applicability of the concept, the following different types of coulometric reagents suitable for nonpolar and polar samples, as well as for samples containing active carbonyl compounds, were investigated: Hydranal Coulomat A, AD, AK, AG-H (modified with chloroform, Merck), and two homemade methanolic reagents modified with 40% (v/v) chloroform and 50% (v/v) formamide, respectively. Except for Hydranal Coulomat A, the mean value of five consecutive titrations of 50 microg water did not deviate by more than 0.2% from the expected value for all reagents. Draining after every titration was sufficient to obtain accurate results, even for Coulomat A which, when used in the commercial diaphragm-free system of Metrohm, gave values which were about 10% too high. As compared to earlier reported results for diaphragm-free coulometry, the descibed modified cell represents a significant improvement, mainly because of the high accuracy achieved for all types of reagents.

  13. Comparison between amperometric and true potentiometric end-point detection in the determination of water by the Karl Fischer method.

    Science.gov (United States)

    Cedergren, A

    1974-06-01

    A rapid and sensitive method using true potentiometric end-point detection has been developed and compared with the conventional amperometric method for Karl Fischer determination of water. The effect of the sulphur dioxide concentration on the shape of the titration curve is shown. By using kinetic data it was possible to calculate the course of titrations and make comparisons with those found experimentally. The results prove that the main reaction is the slow step, both in the amperometric and the potentiometric method. Results obtained in the standardization of the Karl Fischer reagent showed that the potentiometric method, including titration to a preselected potential, gave a standard deviation of 0.001(1) mg of water per ml, the amperometric method using extrapolation 0.002(4) mg of water per ml and the amperometric titration to a pre-selected diffusion current 0.004(7) mg of water per ml. Theories and results dealing with dilution effects are presented. The time of analysis was 1-1.5 min for the potentiometric and 4-5 min for the amperometric method using extrapolation.

  14. Progress in pulsed-current Karl Fischer coulometry using diaphragm-free cells.

    Science.gov (United States)

    Nordmark, U; Cedergren, A

    2000-07-01

    Factors influencing the accuracy of water determinations using diaphragm-free, pulsed current Karl Fischer (KF) coulometry were investigated with the new Metrohm 756 instrument. Results obtained with commercially available reagents from Riedel-deHaen and Merck were compared with home-made ones that were especially designed to minimize the formation of iodine-consuming reduction products generated in the cathode reaction. Positive errors in the range 2-5% were found for the commercial reagents as compared to 0.2-1% for the home-made ones which were buffered at about pH 10 containing modifiers like chloroform, hexanol or ethylene glycol. Except for the composition of the KF-reagent, the cathode current density and the titration rate were found to be critical parameters for the accuracy of the determinations. For all reagents investigated, the best results were obtained for the maximum generator current 400 mA (corresponding to a current density of 1,400 mA cm(-2)) in combination with a maximum titration rate of 2,000 microg min(-1). Surprisingly, the errors found under optimum conditions for the pulse technique were always somewhat larger than the corresponding values obtained with continuous coulometry.

  15. Certification of the reference material of water content in water saturated 1-octanol by Karl Fischer coulometry, Karl Fischer volumetry and quantitative nuclear magnetic resonance.

    Science.gov (United States)

    Wang, Haifeng; Ma, Kang; Zhang, Wei; Li, Jia; Sun, Guohua; Li, Hongmei

    2012-10-15

    Certified reference materials (CRMs) of water content are widely used in the calibration and validation of Karl Fischer coulometry and volumetry. In this study, the water content of the water saturated 1-octanol (WSO) CRM was certified by Karl Fischer coulometry, volumetry and quantitative nuclear magnetic resonance (Q NMR). The water content recovery by coulometry was 99.76% with a diaphragm-less electrode and Coulomat AG anolyte. The relative bias between the coulometry and volumetry results was 0.06%. In Q NMR, the water content of WSO is traceable to the International System (SI) of units through the purity of internal standard. The relative bias of water content in WSO between Q NMR and volumetry was 0.50%. The consistency of results for these three independent methods improves the accuracy of the certification of the RM. The certified water content of the WSO CRM was 4.76% with an expanded uncertainty of 0.09%.

  16. Reaction rates between water and some modified rapidly-reacting Karl Fischer reagents.

    Science.gov (United States)

    Cedergren, A

    1978-04-01

    Rate constants were determined for the reaction between water and various modified Karl Fischer reagents containing formamide, dimethylformamide or N-methylformamide. It was shown that the reaction rate can be increased by a factor of 100 by using a reagent containing 40% v/v formamide in pyridine compared to that obtained by use of the conventional methanolic reagent.

  17. Conditions for accurate Karl Fischer coulometry using diaphragm-free cells.

    Science.gov (United States)

    Nordmark, U; Cedergren, A

    2000-01-01

    Factors influencing the extent of formation of oxidizable reduction products in coulometric cells used for Karl Fischer (KF) determination of water were investigated. For methanolic KF reagents buffered with imidazole (Im) or diethanolamine (DEA) (separately or in combination), three parameters were found to be of outmost importance: the cathodic current density, the pH, and the concentration of protonated base (ImH+ or DEAH+). For reagents buffered with only Im, the relative formation of oxidizable reduction products varied in the range 2-40%; i.e., 51-70 micrograms of water was found for a 50 micrograms water sample, depending on the above-mentioned parameters. The lowest values were observed for reagents having a pH around 10 in combination with cathodic current densities in the range 2000-5000 mA cm-2. For all the Imbuffered reagents investigated, the addition of modifiers such as chloroform, hexanol, and carbon tetrachloride was found to decrease the formation of oxidizable reduction products significantly. For example, a reagent buffered at pH 10 containing 1 M hexanol gave less than 0.3% formation in the current density interval from 200 to 4000 mA cm-2. The best reagents based on the above-mentioned modifiers were tested in the continuous coulometric mode with errors typically in the interval 0-0.5% using optimum conditions. One prerequisite for obtaining such small errors with diaphragm-free continuous coulometry is to use a cathode area no larger than 0.002 cm2. For some of the reagents based on both Im and DEA, the formation of oxidizable reduction products was close to zero at certain current densities, although the analytical performance was not as good as for the reagents buffered solely by Im due to longer conditioning and titration times.

  18. Modification of Karl Fischer Method for Determination of Water in light Petroleum Products Including Aviation Fuels

    Directory of Open Access Journals (Sweden)

    R. C. Misra

    1971-04-01

    Full Text Available Classical Karl Fischer method has been modified so as to make it suitable for determining free and dissolved water present in aviation fuels in excess of 10 ppm which is considered as limiting concentration value for safe fueling of aircrafts particularly in the arduous climatic conditions as encountered in military operations. The modified method employed a special ethylene glyccl solvent mixture and another water saturated fuel sample as blank.

  19. Determination of kinetics of the karl Fischer reaction based on coulometry and true potentiometry.

    Science.gov (United States)

    Cedergren, A

    1996-03-01

    A new measurement technique based on a combination of coulometry and zero-current potentiometry is described for determination of the kinetics of rapidly reacting Karl Fischer (KF) reagents. This makes it possible to determine the order as well as the rate constant for large variations in the concentrations of iodine and water present during a titration. It was shown that for imidazole-based methanolic reagents exposed to a large variation in the concentration of water, the KF reaction is first order with respect to iodine, sulfur dioxide, and water only for reagents in which the concentration of nonprotonated imidazole is very low. The rate constant determined for such a reagent (1 M imidazole, 0.8 M sulfur dioxide, 0.1 M iodine) was equal to that reported earlier in the literature. Regions showing first-order kinetics were also found for low concentrations of water when imidazole concentrations up to 2 mol/L were used, provided that these reagents had a quotient [Im](free)/[ImH(+)] around 4. In the interval 2-8 mol/L of imidazole, the order of the reaction with respect to iodine was, in most cases, one-half, while it was changed to between one-half and one with respect to water. The rate of the KF reaction was found to increase by nearly 5 orders of magnitude for a reagent in which the concentration of nonprotonated imidazole was increased from 0 (rate constant equal to 2.6 × 10(3) L(2) mol(-)(2) s(-)(1)) to about 7 mol/L. For most of these reagents, a recovery rate close to 100% was attained. A high concentration of nonprotonated imidazole in combination with a high concentration of sulfur dioxide could, however, lead to a change in stoichiometry of the KF reaction when larger amounts of water were determined (250 μg of water added to 3.4 mL of reagent solution). A reaction scheme is proposed which might explain this change in stoichiometry observed for some reagent compositions. By use of the described most rapidly reacting reagents, it was shown to be

  20. Efficiency of methods for Karl Fischer determination of water in oils based on oven evaporation and azeotropic distillation.

    Science.gov (United States)

    Larsson, William; Jalbert, Jocelyn; Gilbert, Roland; Cedergren, Anders

    2003-03-15

    The efficiency of azeotropic distillation and oven evaporation techniques for trace determination of water in oils has recently been questioned by the National Institute of Standards and Technology (NIST), on the basis of measurements of the residual water found after the extraction step. The results were obtained by volumetric Karl Fischer (KF) titration in a medium containing a large excess of chloroform (> or = 65%), a proposed prerequisite to ensure complete release of water from the oil matrix. In this work, the extent of this residual water was studied by means of a direct zero-current potentiometric technique using a KF medium containing more than 80% chloroform, which is well above the concentration recommended by NIST. A procedure is described that makes it possible to correct the results for dilution errors as well as for chemical interference effects caused by the oil matrix. The corrected values were found to be in the range of 0.6-1.5 ppm, which should be compared with the 12-34 ppm (uncorrected values) reported by NIST for the same oils. From this, it is concluded that the volumetric KF method used by NIST gives results that are much too high.

  1. DETERMINATION OF WATER CONTENT IN PYROLYTIC TARS USING COULOMETRIC KARL-FISHER TITRATION

    Directory of Open Access Journals (Sweden)

    Lenka Jílková

    2017-02-01

    Full Text Available The liquid organic fraction of pyrolytic tar has a high energy value which makes possible its utilization as an energy source. However, before utilization, it is crucial to remove water from the liquid fraction. The presence of water reduces the energy value of pyrolytic tars. Water separation from the organic tar fraction is a complex process, since an emulsion can be readily formed. Therefore, after phase separation, it is important to know the residual water content in the organic phase and whether it is necessary to further dry it. The results presented in this manuscript focus on a water determination in liquid products from coal and biomass pyrolysis by a coulometric Karl‑Fischer titration. The Coulometric Karl‑Fischer titration is often used for a water content determination in gaseous, liquid and solid samples. However, to date, this titration method has not been used for a water determination in tars. A new water determination method, which has been tested on different types of tar, has been developed. The Coulometric Karl‑Fischer titration is suitable for tar samples with a water content not greater than 5 wt. %. The obtained experimental results indicate that the new introduced method can be used with a very good repeatability for a water content determination in tars.

  2. Coulometric trace determination of water by using Karl Fischer reagent and potentiometric end-point detection.

    Science.gov (United States)

    Cedergren, A

    1974-06-01

    A new approach to the determination of water via the Karl Fischer reaction is described. Iodine is coulometrically generated and the end-point corresponding to a slight excess of iodine, is detected potentiometrically with a non-polarized platinum electrode. Samples of 1-500 mul containing 0.05-200 mug of water were analysed with a standard deviation of 0.015 mug in the range 0.05-20 mug of H(2)O. A specially constructed electrolysis cell was used in combination with an LKB 16300 Coulometric Analyzer and the time for a complete analysis was 1-4 min, depending on sample size. The reagent composition has been optimized in order to enhance the rate of the main reaction and to minimize the extent of side-reactions. Decreasing the temperature reduced the extent of side-reactions. The displacement of end-point potential on dilution was studied and a correction is discussed.

  3. Electrochemical determination of water in environmental hydraulic fluids using the karl Fischer reaction.

    Science.gov (United States)

    Cedergren, A; Lundström, M

    1997-10-01

    Different procedures based on the Karl Fischer reaction were investigated with respect to their applicability for water determinations in environmental hydraulic fluids:  (i) continuous coulometry using a recently described diaphragm-free cell; (ii) on-line stripping of water at elevated temperature using either continuous coulometry or direct potentiometry for detection of the liberated water. Except for one of the oils, Statoil PA, which is a poly(α-olefin) with certain polymers added, no significant difference was found among coulometry using an optimized imidazole-buffered methanolic reagent containing 75% (v/v) chloroform, the two different stripping techniques (working in the temperature interval 100-110 °C), and the commercially available Hydranal Coulomat AG-H. The high stability and sensitivity of the coulometric technique described made it possible to work with sample amounts in the low milligram-range, and this is shown to increase the reliability of the coulometric method as compared to normally used procedures.

  4. Comparison between THE oven and THE Karl Fischer methodS for THE determination of the moisture content of maize (Zea mays L. and soya (Glycine max (L Merrill seeds

    Directory of Open Access Journals (Sweden)

    M.A.A TILLMANN

    1996-01-01

    Full Text Available The objective of the present paper was to compare the seed water content of maize and soya, obtained by the oven method at different temperatures and the Karl Fischer method. The water contents used were 11.2 %, 12.8 % and 16.2 % for maize and 10.7 %, 12.4 % and 16.0 % for soya. Samples were dried for a sufficiently long time in order to obtain the same results in both methods. The results indicate that the official method for seed moisture determination (105oC oven method should be revised in order to obtain more reliable results. The drying time in the oven varied according to the seed water content and the temperature used.O objetivo da pesquisa foi comparar os teores de água de sementes de milho e de soja obtidos pelos métodos da estufa e de Karl Fischer. Os teores de água utilizados foram 11,2% 12,8% e 16,2% para sementes de milho e 10,7%, 12,4% e 16,0% para sementes de soja. Para as determinações dos teores de água nas sementes foi utilizado o método da estufa com diferentes temperaturas, sendo as amostras secadas por um período suficiente para obter os mesmos resultados obtidos pelo método de Karl Fischer. Os resultados indicaram que o método oficial para a determinação do teor de água em sementes (método da estufa, a 105oC precisa ser revisado para a obtenção de resultados com maior precisão. O tempo de permanência das sementes na estufa, para a determinação da umidade, varia conforme o teor de água das sementes e da temperatura utilizada.

  5. 卡尔费休法测定胡椒水分含量的比较研究%Comparison on Determining Water in Pepper by Karl Fischer Method

    Institute of Scientific and Technical Information of China (English)

    吴琼; 宗迎; 徐志; 张月

    2013-01-01

    以蒸馏法测定胡椒水分含量结果为基准,比较卡尔费休容量法测定胡椒(Piper nigrum L.)水分的准确度和精确度,并获得校正系数平均值2.18.结果表明:卡尔费休法可达到蒸馏法的测定准确度和精确度,而且操作简便,是可靠的胡椒水分含量测定方法.%The accuracies and precisions of the pepper water contents tested by the Carl-Fischer method were compared with the toluene distillation method as a standard conventional method. The results showed that the oxidation adjusting coefficients for the Carl-Fischer method were 2.18. The accuracies and precisions of the Carl-Fischer method were as the same as the toluene distillation method in determining pepper water by the Carl-Fischer method. The Carl-Fischer method is facility and credibility. It can be applied in measurement of pepper water.

  6. Rapid Determination on the Water Content in General Diesel Fuels by Automatic Karl Fischer%全自动卡尔费休水分测定仪快速测定普通柴油中的微量水分

    Institute of Scientific and Technical Information of China (English)

    王剑飞; 刘胤璇; 李燕; 李梦迪

    2014-01-01

    The study aims to establish the rapid analysis method to determine water in general diesel fuels by antomatic Karl Fischer method. The experiment evaluated the general diesel fuels with methanol, Trichloromethane, n-heptane, carbon tetrachloride of selectivity. It proved by the experiment using methanol-chloroform binary mixed system with 1:3 matching for the determination of trace moisture in general diesel fuels, which have quick and easy operation, stable and reliable results.%本实验建立全自动卡尔费休水分测定仪快速测定普通柴油中微量水分的方法,并且评价了普通柴油对甲醇、三氯甲烷、正庚烷、四氯化碳等有机溶剂的选择性,经实验证明采用甲醇-三氯甲烷二元混合体系,配比为1:3进行普通柴油中微量水分测定,操作快速简便,结果稳定可靠。

  7. Karl Marx' glemte arvtager

    DEFF Research Database (Denmark)

    Jakobsen, Uffe

    1988-01-01

    For 50 år siden hyldede avisen 'Social-Demokraten' Karl Kautsky (1854-1938) som "den største Tænker inden for den socialdemokratiske Arbejderbevægelse". I perioden fra Friedrich Engels' død i 1895 til 1. Verdenskrigs udbrud i 1914 blev Karl Kautsky alment anset som Karl Marx's arvtager inden for ...

  8. Karl Ristikivi prantsuse keeles

    Index Scriptorium Estoniae

    2003-01-01

    29. ja 30. mail Tallinna Kirjanike Majas ja 31. mail Tartu Kirjanduse Majas esinevad näitlejad Ene Rämmeld ja Claude Merlin Karl Ristikivi luulekavaga "Inimese teekond" (tõlkija Tarah Montbélialtz). Vt. ka Looming, 2003, nr. 6, lk. 953

  9. Kalevipojad tulevad / Karl Kello

    Index Scriptorium Estoniae

    Kello, Karl, 1950-

    2004-01-01

    Kuressaare Kuursaalis näidatakse kadripäeval nelja Ruta Celma ja Karl Kello kultuuriloolist dokumentaalfilmi : "Narr Jumala kojas" (2000), "Phaetonit otsides" (1999), "Eestlased Lätis" (2004) ja Kalevipoja temaatikat arendav "Küll siis Kalev..." (2004). Filmide operaator on Arvo Vilu. Artikli autor kõneleb ka nende filmide seostest Saaremaaga

  10. Karl Ristikivi prantsuse keeles

    Index Scriptorium Estoniae

    2003-01-01

    29. ja 30. mail Tallinna Kirjanike Majas ja 31. mail Tartu Kirjanduse Majas esinevad näitlejad Ene Rämmeld ja Claude Merlin Karl Ristikivi luulekavaga "Inimese teekond" (tõlkija Tarah Montbélialtz). Vt. ka Looming, 2003, nr. 6, lk. 953

  11. Karl Lagerfeld obidelsja

    Index Scriptorium Estoniae

    2006-01-01

    Moekunstnik Karl Lagerfeld kaebas kohtusse raamatu "The Beautiful Fall : Fashion, Genius and Glorious Excess in 1970s Paris" autori Alicia Drake'i. Raamat räägib Lagerfeldi noorusajast ja tema konkurentsist moekunstnik Yves Saint Laurent'iga 1970. aastate Pariisis

  12. Carl eller Karl?

    DEFF Research Database (Denmark)

    Eggert, Birgit

    2013-01-01

    I den danske fornavnemode findes en række navne i flere forskellige stavemåder som ikke har indflydelse på navnenes udtale. Navnene udtales ens hvad enten de staves Carl eller Karl og Camilla eller Kamilla. Med udgangspunkt i de 50 mest populære pige- og drengenavne hvert år siden 1985 har jeg set...

  13. Karl Lagerfeld obidelsja

    Index Scriptorium Estoniae

    2006-01-01

    Moekunstnik Karl Lagerfeld kaebas kohtusse raamatu "The Beautiful Fall : Fashion, Genius and Glorious Excess in 1970s Paris" autori Alicia Drake'i. Raamat räägib Lagerfeldi noorusajast ja tema konkurentsist moekunstnik Yves Saint Laurent'iga 1970. aastate Pariisis

  14. Protamine titration.

    Science.gov (United States)

    Newall, Fiona

    2013-01-01

    Protamine titration is the gold standard method for the measurement of unfractionated heparin (UFH) concentration in plasma. Protamine titration produces reliable and reproducible results; however it is -generally not considered a convenient assay for current clinical management of UFH as it is not readily automated (Olson et al. Arch Pathol Lab Med 122(9):782-798, 1998). Early clinical trials of UFH therapy determined that a heparin concentration of 0.2-0.4 U/ml by protamine titration correlated to an APTT of 1.5-2.5 times higher compared to baseline values produced desirable UFH safety and efficacy outcomes (Hull et al. N Engl J Med 315(18):1109-1114, 1986; Hull et al. N Engl J Med 322:1260-1264, 1990; Turpie et al. N Engl J Med 320:352-357, 1989; Brill-Edwards et al. Ann Intern Med 119(2):104-109, 1993; Hull Int Angiol 14(1):32-34, 1995). Such studies paved the way to the current view that it is no longer ideal to manage UFH based solely upon a 1.5-2.5 times prolongation of the "normal" APTT. Most advisory bodies recommend therapeutic APTTs be determined by correlating APTT results with therapeutic UFH levels as measured by anti-Xa assay (0.35-0.7 U/ml) or protamine titration (0.2-0.4 U/ml) (Hirsh and Raschke. Chest 126(3):188S-203S, 2004) (see Note 1). The concentration of UFH in a sample is measured by determining the amount of protamine required to return the thrombin clotting time (TCT) test (prolonged by UFH) to a pre-UFH level (Laffan and Manning. Dacie and Lewis: practical haematology. Churchill Livingstone: London, 2001).

  15. Sir Karl Popper and Education

    Science.gov (United States)

    McNamara, D. R.

    1978-01-01

    Sir Karl Popper is one of England's most distinguished contemporary philosophers and it is surprising that his thought has not permeated and informed educational discussion. This paper suggests that educationists have much to learn from Karl Popper's writings and explores ways in which his ideas can illuminate and advance discussion about…

  16. 1990 Fischer Standard study

    Energy Technology Data Exchange (ETDEWEB)

    Roubik, G.J.

    1990-09-12

    The purpose of this work is to develop a set of Titanium areal density standards for calibration and maintenance of the Fischer`s X-ray Fluorescence measurement system characterization curve program. The electron microprobe was calibrated for Titanium films on ceramic substrates using an existing set of laboratory standards (Quantity: 6 Range: 0.310 to 1.605). Fourteen source assemblies were measured and assigned values. These values are based on a mean calculation, of five separate readings, from best curve fit equations developed form the plot of the laboratory standards areal density (Source Measure) versus electron microprobe measurement (reading). The best fit equations were determined using the SAS General Linear Modeling (GLM) procedure. Four separate best fit equations were evaluated (Linear, Quadratic, Cubic and Exponential). Areal density values for the Fischer Standards appear here ordered by best fit equation based on maximum R{sup 2}.

  17. Karl Jaspers' multiperspectivalism.

    Science.gov (United States)

    Wiggins, Osborne P; Schwartz, Michael Alan

    2013-01-01

    In later editions of his General Psychopathology, Karl Jaspers prescribes many different methods and theoretical points of view for psychopathologists to utilize. Each of these perspectives on the subject matter of psychopathology, however, gives the investigator access to only one dimension of the patient's being. Hence, Jaspers insists that several different perspectives must be employed in order to avoid a one-sided and partial comprehension of the patient and his or her problem. He advocates a multiperspectival approach in psychopathology. Nevertheless, Jaspers remains aware that the patient is a unified whole. This unified whole, however, is not knowable as such, but can rather be approached only under the guidance of an 'idea' of the whole. Jaspers takes the basic notion of 'idea' (Idee) from Kant, but he modifies and uses it for his own purposes. Jaspers' multiperspectivalism may seem to invite charges of relativism because it leaves the psychopathologist to 'pick and choose' any method or theory he or she prefers. This charge is addressed by admitting that there does exist a certain relativism in Jaspers' position in that any one perspective does provide only one approach to the reality of the patient and that other equally useful perspectives could have been chosen. However, each perspective itself can be subjected to test by evidence, and in such tests, claims made from that perspective can be found to be true or false. Helen Longino's theory of scientific knowledge helps support such a thesis.

  18. Karl Popper's Quantum Ghost

    Science.gov (United States)

    Shields, William

    2004-05-01

    Karl Popper, though not trained as a physicist and embarrassed early in his career by a physics error pointed out by Einstein and Bohr, ultimately made substantial contributions to the interpretation of quantum mechanics. As was often the case, Popper initially formulated his position by criticizing the views of others - in this case Niels Bohr and Werner Heisenberg. Underlying Popper's criticism was his belief that, first, the "standard interpretation" of quantum mechanics, sometimes called the Copenhagen interpretation, abandoned scientific realism and second, the assertion that quantum theory was "complete" (an assertion rejected by Einstein among others) amounted to an unfalsifiable claim. Popper insisted that the most basic predictions of quantum mechanics should continue to be tested, with an eye towards falsification rather than mere adding of decimal places to confirmatory experiments. His persistent attacks on the Copenhagen interpretation were aimed not at the uncertainty principle itself and the formalism from which it was derived, but at the acceptance by physicists of an unclear epistemology and ontology that left critical questions unanswered. In 1999, physicists at the University of Maryland conducted a version of Popper's Experiment, re-igniting the debate over quantum predictions and the role of locality in physics.

  19. In memoriam : Karl R. Popper

    Directory of Open Access Journals (Sweden)

    Cecilia Tohăneanu

    2014-04-01

    Full Text Available Dedicated to Karl Popper’s memory, this essay aims at following the echo of his critical rationalism and how it has been received by Mario Bunge, one of the most prominent contemporary philosopher of science – an admirer, later a critic of Popper’s social and political philosophy. The main goal of such an endeavor is to find out where could have been Popper wrong – from Bunge’s view point – and take note of the arguments of both of them, thus hoping to get closer to the truth, as Sir Karl said.

  20. Sõrmuste isand Karl Fritsch / Merike Alber

    Index Scriptorium Estoniae

    Alber, Merike

    2008-01-01

    Saksa ehtekunstniku Karl Fritschi (sünd. 1963) näitus "Metrosideros robusta. Ehted" Eesti Tarbekunsti- ja Disainimuuseumis kuni 29. VI. Karl Fritsch pälvis 2006. a. Francoise van den Boschi (hollandi ehtekunstnik, 1944-1977) auhinna, 1995. ja 2007. a. Herbert Hoffmanni preemia. Darling Publications kirjastas Karl Fritschist raamatud "Metrosideros Robusta" ja "Baby Brick"

  1. Sõrmuste isand Karl Fritsch / Merike Alber

    Index Scriptorium Estoniae

    Alber, Merike

    2008-01-01

    Saksa ehtekunstniku Karl Fritschi (sünd. 1963) näitus "Metrosideros robusta. Ehted" Eesti Tarbekunsti- ja Disainimuuseumis kuni 29. VI. Karl Fritsch pälvis 2006. a. Francoise van den Boschi (hollandi ehtekunstnik, 1944-1977) auhinna, 1995. ja 2007. a. Herbert Hoffmanni preemia. Darling Publications kirjastas Karl Fritschist raamatud "Metrosideros Robusta" ja "Baby Brick"

  2. Karl Ove Knausgaard's My Struggle

    DEFF Research Database (Denmark)

    Schmitt, Arnaud; Kjerkegaard, Stefan

    2016-01-01

    In this study of Karl Ove Knausgaard’s My Struggle, the authors theorize what paratextual information does to one’s reading, especially in autobiography informed literature. Although My Struggle can be read both as memoir and novel, and even as autofiction, Knausgaard is aiming at a higher truth...

  3. Karl Marx 1864 og forsigtighedsprincippet

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    2015-01-01

    Artiklen analyserer divergerende versioner af den tekst, som Karl Marx efter dannelsen af den 1.Internationale Arbejderassociation i London september 1864 har oversat fra sit engelske original (Inaugural Address...), der udkom i november, til en tysk version med overskriften 'Manifest an die arbe...

  4. Karl Stern (1906-1975).

    Science.gov (United States)

    Stahnisch, Frank W; Pow, Stephen

    2015-01-01

    The forced migration process of German-speaking neurologists and psychiatrists under the Nazis during the 1930s and 40s is often preoccupied solely with "successful" concepts and therapeutic approaches. The case of German-Canadian neurologist Karl Stern (1906-1975) is very instructive, however, since the process of forced migration, for him, proved to be a transitionary process from his former cutting edge work in neuropathology and holist neurology in Germany to clinical psychiatry and the development of the new discipline of geriatric medicine in Canada.

  5. Karl Konrad Grass jumalainimeste uurijana / Alar Laats

    Index Scriptorium Estoniae

    Laats, Alar

    2006-01-01

    Karl Konrad Grass oli 19. sajandil Dorpati keiserliku ülikooli usuteaduskonna Uue Testamendi õppejõud, kes tegeles hobi korras idakristluse (vene sektid) uurimisega. Tema peateoseks on uurimus "Die russischen Sekten". Ettekanne konverentsil 15.-16. aprill 2005. a.

  6. Karl Konrad Grass jumalainimeste uurijana / Alar Laats

    Index Scriptorium Estoniae

    Laats, Alar

    2006-01-01

    Karl Konrad Grass oli 19. sajandil Dorpati keiserliku ülikooli usuteaduskonna Uue Testamendi õppejõud, kes tegeles hobi korras idakristluse (vene sektid) uurimisega. Tema peateoseks on uurimus "Die russischen Sekten". Ettekanne konverentsil 15.-16. aprill 2005. a.

  7. KARL MAYER Aims to Shape The Future

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Review of KARL MAYER at ITMA ASIA + CITME 2012 in Shanghai This June, during the ITMA ASIA + CITME 2012 exhibition that was held on June 12th-16th in the city of Shanghai, the exhibition stand of Karl Mayer without doubt spotlighted all the attention in the entire warp knitting sector, bringing its clever and innovative solutions to global visitors, particularly the customers in Asia.

  8. Karl Kello - elukutse olla saarlane / Aare Laine

    Index Scriptorium Estoniae

    Laine, Aare, 1951-

    2004-01-01

    Kuressaare Kuursaalis näidati kadripäeval nelja Ruta Celma ja Karl Kello kultuuriloolist dokumentaalfilmi : "Narr Jumala kojas" (2000), "Phaetonit otsides" (1999), "Eestlased Lätis" (2004) ja Kalevipoja temaatikat arendav "Küll siis Kalev..." (2004). Filmide operaator on Arvo Vilu. Artikli autor kõneleb Karl Kellost, tema Karja kiriku ja Kaali järve problemaatika arendustest peale filmide ka kirjasõnas

  9. Karl Kello - elukutse olla saarlane / Aare Laine

    Index Scriptorium Estoniae

    Laine, Aare, 1951-

    2004-01-01

    Kuressaare Kuursaalis näidati kadripäeval nelja Ruta Celma ja Karl Kello kultuuriloolist dokumentaalfilmi : "Narr Jumala kojas" (2000), "Phaetonit otsides" (1999), "Eestlased Lätis" (2004) ja Kalevipoja temaatikat arendav "Küll siis Kalev..." (2004). Filmide operaator on Arvo Vilu. Artikli autor kõneleb Karl Kellost, tema Karja kiriku ja Kaali järve problemaatika arendustest peale filmide ka kirjasõnas

  10. ''Titration'' polymerization of monovinylacetylene

    NARCIS (Netherlands)

    Mavinkurve, A; Visser, S; vandenBroek, W; Pennings, AJ

    1996-01-01

    A polymer consisting of a saturated carbon backbone with pendent acetylenic groups was prepared from monovinylacetylene. A titration was performed between the monomer and tertiary butyllithium, its lithiating agent. The charge transfer complex formed between the solvent THF and the tertiary butyllit

  11. Filtrates & Residues: Olfactory Titration.

    Science.gov (United States)

    Wood, John T.; Eddy, Roberta M.

    1996-01-01

    Presents an experiment that uses a unique acid-base indicator--the odor of raw onion--to indicate the end point of the titration of sodium hydroxide with hydrochloric acid. Allows the student to detect the completion of the neutralization reaction by olfaction rather than sight. (JRH)

  12. Raamaturappija / [Sinijärv, Karl Martin

    Index Scriptorium Estoniae

    Sinijärv, Karl Martin, 1971-

    1997-01-01

    Vandenberg, Philipp. Viies evangeelium; Fischer, Hans. Saatuslik armastus majas nr. 34; Bulgakov, Mihhail. Meister ja Margarita; Paju, Juhan. Katkenud romaan; Duby, Georges. Guillaume le Maréchal ehk Maailma parim rüütel

  13. Raamaturappija / [Sinijärv, Karl Martin

    Index Scriptorium Estoniae

    Sinijärv, Karl Martin, 1971-

    1997-01-01

    Vandenberg, Philipp. Viies evangeelium; Fischer, Hans. Saatuslik armastus majas nr. 34; Bulgakov, Mihhail. Meister ja Margarita; Paju, Juhan. Katkenud romaan; Duby, Georges. Guillaume le Maréchal ehk Maailma parim rüütel

  14. Seitse võistlusromaani / Karl Ristikivi

    Index Scriptorium Estoniae

    Ristikivi, Karl, 1912-1977

    1996-01-01

    Kask, Agu. Unustatud sugpõlv; Rajamaa, Helmi. Varjutatud südamed; Thoen, Aino. Võlaraamat; Veskimäe, Viktor. Kolmas võimalus; Timmukuru, Juhan. Esimesed read; Einer, Karl. Ainult üks valge liblikas; Timmukuru, Juhan. Peep Koordipoja põlistalu

  15. [Karl Landsteiner discovers the blood groups].

    Science.gov (United States)

    Lefrère, J-J; Berche, P

    2010-02-01

    The discovery of ABO blood group was a major step in mastering transfusion therapy. Karl Landsteiner (1868-1843) was the author of this discovery. This paper retraces the hard career of this American scientist of Austrian origin, and describes the circumstances that led his research to the discoveries, which were turning points in the history of the immunology.

  16. Tailored fischer-tropsch synthesis product distribution

    Science.gov (United States)

    Wang, Yong [Richland, WA; Cao, Chunshe [Kennewick, WA; Li, Xiaohong Shari [Richland, WA; Elliott, Douglas C [Richland, WA

    2012-06-19

    Novel methods of Fischer-Tropsch synthesis are described. It has been discovered that conducting the Fischer-Tropsch synthesis over a catalyst with a catalytically active surface layer of 35 microns or less results in a liquid hydrocarbon product with a high ratio of C.sub.5-C.sub.20:C.sub.20+. Descriptions of novel Fischer-Tropsch catalysts and reactors are also provided. Novel hydrocarbon compositions with a high ratio of C.sub.5-C.sub.20:C.sub.20+ are also described.

  17. Karl Popper and Evolutionary Concept of Epistemology

    OpenAIRE

    Ebrahim Ashni Alvandi; Majid Akbari Dehagi

    2008-01-01

    Epistemology and its formational trend have been always one of the discussions in various parts of science; and nowadays modern sciences have plentiful effects on the process of epistemological studies. Different men of letters from various fields have also studied and scrutinized it. Among these researches, evolutionary epistemology wants to explain the process of formation of epistemology by modeling it through evolution theory. Here I do effort to investigate Karl Poppers’ view point of ep...

  18. Fischer-Tropsch synthesis over MOF-supported cobalt catalysts (Co@MIL-53(Al)).

    Science.gov (United States)

    Isaeva, V I; Eliseev, O L; Kazantsev, R V; Chernyshev, V V; Davydov, P E; Saifutdinov, B R; Lapidus, A L; Kustov, L M

    2016-07-26

    Novel nanohybrid materials were prepared by immobilizing Co nanoparticles on a microporous framework MIL-53(Al) as a porous host matrix. The synthesized cobalt-containing materials were characterized by XRD, STEM, and oxygen titration. The catalytic performance of Co@MIL-53(Al) nanohybrids was examined in Fischer-Tropsch synthesis (FTS) for the first time. A higher selectivity to C5+ hydrocarbons and lower selectivity to methane for Co@MIL-53(Al) as compared to conventional Co/Al2O3 were observed.

  19. Novel Fischer-Tropsch catalysts. [DOE patent

    Science.gov (United States)

    Vollhardt, K.P.C.; Perkins, P.

    Novel compounds are described which are used as improved Fischer-Tropsch catalysts particularly for the conversion of CO + H/sub 2/ to gaseous and liquid hydrocarbons at milder conditions than with prior catalysts.

  20. "Unmapped Territories": The Career of Karl Kroeber (1926-2009)

    Science.gov (United States)

    Ruoff, A. Lavonne Brown

    2012-01-01

    Jean Taylor Kroeber, widow of Karl Kroeber, has granted permission for "SAIL" to reprint his "Address to Columbia College Students Elected to the Phi Beta Kappa Society, 18 May 2009" and "An Interview with Karl Kroeber." Conducted by Michael Mallick, the interview was published in the newsletter of the Department of English and Comparative…

  1. Profiles in Research: An Interview with Karl Gustav Joreskog

    Science.gov (United States)

    Wainer, Howard

    2011-01-01

    This article presents an interview with Karl Gustav Joreskog. Karl Gustav Joreskog was born in Amal, Sweden, on April 25, 1935. He did his undergraduate studies at Uppsala University from 1955 to 1957, with a major in mathematics and physics. He received a PhD in statistics at Uppsala University in 1963, and he was a research statistician at…

  2. Perspectiva sobre una Personalidad Senera: Carmen Fischer Ramirez (Perspective on a Singular Personality: Carmen Fischer Ramirez).

    Science.gov (United States)

    Quezeda, Dina Alarcon

    1992-01-01

    Traces the career of Carmen Fischer Ramirez, focusing on her work in improving early childhood education in Chile. Reviews her university career, work with the World Organization for Early Childhood Education, and major publications. (AC)

  3. Perspectiva sobre una Personalidad Senera: Carmen Fischer Ramirez (Perspective on a Singular Personality: Carmen Fischer Ramirez).

    Science.gov (United States)

    Quezeda, Dina Alarcon

    1992-01-01

    Traces the career of Carmen Fischer Ramirez, focusing on her work in improving early childhood education in Chile. Reviews her university career, work with the World Organization for Early Childhood Education, and major publications. (AC)

  4. Karl Kautsky e as origens do Cristianismo

    Directory of Open Access Journals (Sweden)

    Luiz Alberto Moniz Bandeira

    2010-08-01

    Full Text Available Prólogo à obra “A Origem do Cristianismo”, de Karl Kautsky (Rio de Janeiro: Civilização Brasileira, 2010, p. 07-19

  5. Kernaspekte van die kennissosiologie van Karl Mannheim

    Directory of Open Access Journals (Sweden)

    A. D. Louw

    1985-03-01

    Full Text Available The author deals with certain crucial aspects of the sociology of knowledge of Karl Mannheim in view of the fact that he finds that the increase, worldwide, of interest in ideological difficulties in South Africa can fruitfully be dealt with in terms of this form of sociology. This is justified in part by Mannheim's viewpoint that thought is a function of human existence, and this function emanates from needs based on social factors. He traces Mannheim's use of the term ideology (in Sociology, culminating With the Idea that “the birth and death of ideology depends on certain social, economic and 'ecological' factors”. Subsequently he deals with a whole line of aspects of the sociology of knowledge as expounded by Mannheim, culminating in the idea that shifts in views with regard to lifeview and underlying values take place when there is a rapid upward (vertical mobility, leading to uncertainties and a lack of trust in established values.

  6. Karl Korsch e a Comuna de Paris

    Directory of Open Access Journals (Sweden)

    Luciano Cavini Martorano

    2011-03-01

    Full Text Available

    Apesar de haver escrito uma extensa obra que ainda vem sendo editada no seu país natal, o marxista alemão Karl Korsch é praticamente desconhecido no Brasil – exceção feita a alguns poucos pesquisadores. Além da recente edição brasileira de seu importante trabalho Marxismo e filosofia (Editora UFRJ, e de alguns outros textos e artigos que podem ser encontrados em diferentes sites, o acesso ao conjunto de sua obra ainda é bastante difícil.

  7. Divining and knowing: Karl Sudhoff's historical method.

    Science.gov (United States)

    Stein, Claudia

    2013-01-01

    This article investigates the historical method of Karl Sudhoff (1853- 1938), Germany's first professor of medical history. It argues that in order to understand his ideas more fully, we need to step outside the historiography of medical history and assess his methodology in relation to the norms and ideals of German academic history writing in general. The article demonstrates that the philology-based "critical method" of Leopold von Ranke (1795-1886) was central to Sudhoff's methodological thinking. It investigates the underlying philosophical and epistemological assumptions of Ranke's method, which tend to be less appreciated than his overt empiricism and explores how Sudhoff applied these to the new professionalizing subdiscipline of the history of medicine. The article argues that Sudhoff's concerns with the methodology of history, which involved a particular conception of the relationship between the human sciences and the medical sciences, offers compelling addresses to our times.

  8. Novel Attrition-Resistant Fischer Tropsch Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Weast, Logan, E.; Staats, William, R.

    2009-05-01

    There is a strong national interest in the Fischer-Tropsch synthesis process because it offers the possibility of making liquid hydrocarbon fuels from reformed natural gas or coal and biomass gasification products. This project explored a new approach that had been developed to produce active, attrition-resistant Fischer-Tropsch catalysts that are based on glass-ceramic materials and technology. This novel approach represented a promising solution to the problem of reducing or eliminating catalyst attrition and maximizing catalytic activity, thus reducing costs. The technical objective of the Phase I work was to demonstrate that glass-ceramic based catalytic materials for Fischer-Tropsch synthesis have resistance to catalytic deactivation and reduction of particle size superior to traditional supported Fischer-Tropsch catalyst materials. Additionally, these novel glass-ceramic-based materials were expected to exhibit catalytic activity similar to the traditional materials. If successfully developed, the attrition-resistant Fischer-Tropsch catalyst materials would be expected to result in significant technical, economic, and social benefits for both producers and public consumers of Fischer-Tropsch products such as liquid fuels from coal or biomass gasification. This program demonstrated the anticipated high attrition resistance of the glass-ceramic materials. However, the observed catalytic activity of the materials was not sufficient to justify further development at this time. Additional testing documented that a lack of pore volume in the glass-ceramic materials limited the amount of surface area available for catalysis and consequently limited catalytic activity. However, previous work on glass-ceramic catalysts to promote other reactions demonstrated that commercial levels of activity can be achieved, at least for those reactions. Therefore, we recommend that glass-ceramic materials be considered again as potential Fischer-Tropsch catalysts if it can be

  9. 15 aastat hiljem ehk Karl Ristikivi 90 / Janika Kronberg

    Index Scriptorium Estoniae

    Kronberg, Janika, 1963-

    2003-01-01

    XV Ristikivi päeva tähistamisest Ristikivi muuseumis. Karl Ristikivi Seltsi ja Eesti Võrdleva Kirjandusteaduse Assotsiatsiooni konverentsist "Eesti romaan 21. sajandi algul". Ka meenutusi K. Ristikivi loomingule pühendatud konverentsist 1987. a

  10. Märkmeid uusima Preisi tsensuuriinstruktsiooni kohta / Karl Marx

    Index Scriptorium Estoniae

    Marx, Karl

    2000-01-01

    Preisi uue (1841. aasta) tsensuuriinstruktsiooni tõusikliku vaimu vastuolust vana (1818. aasta) tsensuurimääruse ratsionalismiga. Moraali ja religiooni vastuolust. Vt. ka Ain Kaalepi artiklit "Veel Karl Marxist ja tsensuurist

  11. Kes oli rännumees Karl Feyerabend? / Urmas Sutrop

    Index Scriptorium Estoniae

    Sutrop, Urmas, 1956-

    2001-01-01

    Feyerabend, Karl. Kosmopolitische Wanderungen durch Preussen, Curland, Liefland, Litthauen, Vollhynien, Podolien und Schlesien, in der jahren 1795 bis 1798. In Briefen an einen Freund. Bd. 3. 1801. Eestile on pühendatud reisiraamatu 40. kiri

  12. Karl Popper at ninety: Highlights of a lifelong intellectual quest

    Science.gov (United States)

    Selleri, Franco; van der Merwe, Alwyn

    1991-12-01

    On the occasion of his ninetieth birthday, Karl Popper's lifelong pursuit of answers in several areas of scientific and philosophical thinking is briefly traced, mainly with reference to excerpts from his own writings.

  13. Karl Timoleon v. Neff / Carl Christian Vogel von Vogelstein

    Index Scriptorium Estoniae

    Vogel von Vogelstein, Carl Christian, 1788-1868

    2004-01-01

    "Ruskii Bibliofil", 1912, nr. 4, lk. 34; fotol tekst: "Piano di Sorrento, Villa Pisani, 20. Juli 1843". Neffi käega kirjutatud: "Karl Timoleon v. Neff geboren in Pühs in Estland im Jahre 1804 d. 2. October"

  14. Balti Maailmanõukogu aktsioonid Helsingis 1975 / Karl Laantee

    Index Scriptorium Estoniae

    Laantee, Karl, 1927-2007

    2006-01-01

    1975. a. Helsingis peetud Euroopa Julgeoleku ja Koostöö Konverentsi Balti delegatsiooni liikme Karl Laantee tekst, mille ta esitas 4. augustil 1975 Balti Maailmanõukogu pressikonverentsil "Continental"hotellis Stockholmis Rootsi Eestlaste Esinduse pressiinfona

  15. Astronaut Karl Henize with soft drink in middeck area

    Science.gov (United States)

    1985-01-01

    Astronaut Karl Henize drinks from a special carbonated beverage dispenser labeled Pepsi while floating in the middeck area of the shuttle Challenger. Note the can appears to have its own built in straw.

  16. Märkmeid uusima Preisi tsensuuriinstruktsiooni kohta / Karl Marx

    Index Scriptorium Estoniae

    Marx, Karl

    2000-01-01

    Preisi uue (1841. aasta) tsensuuriinstruktsiooni tõusikliku vaimu vastuolust vana (1818. aasta) tsensuurimääruse ratsionalismiga. Moraali ja religiooni vastuolust. Vt. ka Ain Kaalepi artiklit "Veel Karl Marxist ja tsensuurist

  17. Kes oli rännumees Karl Feyerabend? / Urmas Sutrop

    Index Scriptorium Estoniae

    Sutrop, Urmas, 1956-

    2001-01-01

    Feyerabend, Karl. Kosmopolitische Wanderungen durch Preussen, Curland, Liefland, Litthauen, Vollhynien, Podolien und Schlesien, in der jahren 1795 bis 1798. In Briefen an einen Freund. Bd. 3. 1801. Eestile on pühendatud reisiraamatu 40. kiri

  18. Saage tuttavaks : Elisabeth ja Karl von Hoerschelmann / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2004-01-01

    Kuraator M. Levin kuni 10. X 2004 Adamson-Ericu muuseumis avatud näitusest "Tuntud ja tundmatud Elisabeth von Rosendorff-Hoerschelmann ja Karl von Hoerschelmann". Enamik töid on kunstnike laste Konstantin Hoerschelmanni ja Anna Röder-Hoerschelmanni omand. Elisabeth Rosendorff (1898-1984) sündis Virumaal Maidlas eesti perekonnas, Karl von Hoerschelmann (1899-1951) Sevastoopolis saksa perekonnas

  19. Saage tuttavaks : Elisabeth ja Karl von Hoerschelmann / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2004-01-01

    Kuraator M. Levin kuni 10. X 2004 Adamson-Ericu muuseumis avatud näitusest "Tuntud ja tundmatud Elisabeth von Rosendorff-Hoerschelmann ja Karl von Hoerschelmann". Enamik töid on kunstnike laste Konstantin Hoerschelmanni ja Anna Röder-Hoerschelmanni omand. Elisabeth Rosendorff (1898-1984) sündis Virumaal Maidlas eesti perekonnas, Karl von Hoerschelmann (1899-1951) Sevastoopolis saksa perekonnas

  20. Fischer decomposition in symplectic harmonic analysis

    OpenAIRE

    Brackx, Fred; De Schepper, Hennie; Eelbode, David; Lávička, Roman; Soucek, Vladimir

    2014-01-01

    In the framework of quaternionic Clifford analysis in Euclidean space , which constitutes a refinement of Euclidean and Hermitian Clifford analysis, the Fischer decomposition of the space of complex valued polynomials is obtained in terms of spaces of so-called (adjoint) symplectic spherical harmonics, which are irreducible modules for the symplectic group Sp. Its Howe dual partner is determined to be sl(2, C) circle plus sl(2, C) = so(4, C).

  1. A Conversation with Karl K. Turekian

    Science.gov (United States)

    Turekian, Karl K.; Cochran, J. Kirk

    2012-01-01

    Editors' Note Each year, the editorial board invites a distinguished member of the oceanographic community to contribute a prefatory chapter; this year, we were delighted when Karl Turekian, Sterling Professor of Geology and Geophysics at Yale, accepted our invitation. Over the course of a long and productive career, Dr. Turekian has pursued his interests in marine and atmospheric geochemistry by using natural radioactive and radiogenic isotopes to study Earth's evolution and the impacts of global change. He has also directed both the Center for the Study of Global Change at Yale and the Yale Institute for Biospheric Studies. In this interview, conducted by his former student Kirk Cochran, Dr. Turekian tells the story of his early career and discusses some of the major scientific challenges and opportunities faced along the way. His personal account of the rise of geochemistry is a charming story of how chance events and personalities impact scientific careers. His technical insight into the future of this field is illuminating, particularly for scientific outsiders who appreciate the central role of geochemistry in discerning and understanding patterns of global change. Craig A. Carlson and Stephen J. Giovannoni, Editors [Figure: see text

  2. Karl Marx dan Konsep Perjuangan Kelas Sosial

    Directory of Open Access Journals (Sweden)

    Indriaty Ismail

    2012-06-01

    Full Text Available ¬¬This article explores the history of the renowned world economic and political reformist, Karl Marx with a special focus on the social class concept. It also discusses to what extent that the Marx’s concept of social class struggle is capable to provide a way out to the proletariats, to free themselves from the chains of cruelty, violence and alienation in the capitalist system. Our main focal point is to scrutinize the relationship between the concepts of social class struggle and the need for a social revolution as a catalyst for the formation of a classless society. Along the way, we studied and analyzed the documents produced on the primary sources covering major works of Marx and the secondary sources consisting reviews of the Marx’s class concept. As a result, we found out that Marx’s concept of class fight is competent to represent the oppressed group to battle for their freedom rights. The Proletariat dictatorship attitude was used as their main shield to face the threat of the capitalist class. Marx’s ultimate success is realized through a burst of ideas and beliefs that supports the ideas of egalitarian Communism although many contradictions arise between the ideas of Marx and the 20th centuries Communism when they are translated into practice.

  3. Karl Mannheim’s Jewish Question

    Directory of Open Access Journals (Sweden)

    David Kettler

    2012-04-01

    Full Text Available In this paper, we explore Karl Mannheim’s puzzling failure (or refusal to address himself in any way to questions arising out of the position of Jews in Germany, either before or after the advent of Nazi rule—and this, notwithstanding the fact, first, that his own ethnic identification as a Jew was never in question and that he shared vivid experiences of anti-Semitism, and consequent exile from both Hungary and Germany, and, second, that his entire sociological method rested upon using one’s own most problematic social location—as woman, say, or youth, or intellectual—as the starting point for a reflexive investigation. It was precisely Mannheim’s convictions about the integral bond between thought grounded in reflexivity and a mission to engage in a transformative work of Bildung that made it effectively impossible for him to formulate his inquiries in terms of his way of being Jewish. It is through his explorations of the rise and fall of the intellectual as socio-cultural formation that Mannheim investigates his relations to his Jewish origins and confronts the disaster of 1933. The key to our puzzle is to be found in the theory of assimilation put forward in the dissertation of his student, Jacob Katz.

  4. Information Systems Foundations - Karl Popper's third world

    Directory of Open Access Journals (Sweden)

    Craig McDonald

    2002-11-01

    Full Text Available The various information professions have matured separately over the years, developing different bodies of theory and practice to meet their evolving purposes and needs. A problem arises however, when different information professions address the same knowledge domain and there is no explicit correspondence between the conceptual structures embedded independently in each. In this situation, a knowledge worker involved in the domain is faced with a range of possibly incompatible structures presented in different forms by a range of information professions. This is a common problem that is being exacerbated by the explosion in information production and the widening access to information distribution technology, notably the World Wide Web. Information Systems now need to combine the best of what the information professions in a domain have to offer the domain’s knowledge workers. This paper examines the problem by exploring one of the foundations of the information disciplines - Karl Popper’s 3 Worlds theory, applying it to a case study and suggesting that the Information Systems discipline alone has a sufficiently broad agenda to integrate the various Informatics themes needed to support today’s knowledge workers.

  5. Risks and benefits of rapid clozapine titration

    Directory of Open Access Journals (Sweden)

    Jeannie D. Lochhead

    2016-05-01

    Full Text Available Clozapine is often considered the gold standard for the treatment of schizophrenia. Clinical guidelines suggest a gradual titration over 2 weeks to reduce the risks of adverse events such as seizures, hypotension, agranulocytosis, and myocarditis. The slow titration often delays time to therapeutic response. This raises the question of whether, in some patients, it may be safe to use a more rapid clozapine titration. The following case illustrates the potential risks associated with the use of multiple antipsychotics and rapid clozapine titration. We present the case of a young man with schizophrenia who developed life threatening neuroleptic malignant syndrome (NMS during rapid clozapine titration and treatment with multiple antipsychotics. We were unable to find another case in the literature of NMS associated with rapid clozapine titration. This case is meant to urge clinicians to carefully evaluate the risks and benefits of rapid clozapine titration, and to encourage researchers to further evaluate the safety of rapid clozapine titration. Rapid clozapine titration has implications for decreasing health care costs associated with prolonged hospitalizations, and decreasing the emotional suffering associated with uncontrolled symptoms of psychosis. Clozapine is considered the most effective antipsychotic available thus efforts should focus on developing strategies that would allow for safest and most efficient use of clozapine to encourage its utilization for treatment resistance schizophrenia.

  6. Karl Barth and the future of dogmatic theology

    Directory of Open Access Journals (Sweden)

    Alasdair I.C. Heron

    2002-11-01

    Full Text Available The article discusses Karl Barth’s contribution to dogmatic theology. It describes Karl Barth’s personality and shows how his theology was put to practice in writing, in teaching, in debate, in conflict, in friendship and in opposition. Some negative comments on Barth are for example levelled at his liturgical insensitivity, unbalanced and exclusive emphasis on preaching, and his individualistic dislike of the established church, its governing structures and baptismal practice. The article focuses on Barth’s impulses for the discipline of dogmatics and demonstrates developments and directions in his work. Critically reservations regarding instances where it might seem better for theologians not to follow Barth, are  specified.    The  article  also  offers  a  glimpse  into  the  future  of  dogmatic theology seen through the lens of Karl Barth.

  7. Eli Fischer-Jørgensen, Eugeniu Coseriu et Louis Hjelmslev

    DEFF Research Database (Denmark)

    Jensen, Viggo Bank

    2015-01-01

    Based on a correspondence between Eugenio Coseriu (1921-2002) and Eli Fischer-Jørgensen (1911-2010), the article discusses the importance of Louis Hjelmslev (1899-1965) for the development of the theory of Coseriu. In a letter dated 1955, Fischer-Jørgensen agrees with Coseriu in his criticism of ...

  8. Nap-titration : An effective alternative for continuous positive airway pressure titration

    NARCIS (Netherlands)

    Hoekema, A; Stegenga, B; Meinesz, AF; van der Hoeven, JH; Wijkstra, PJ

    2006-01-01

    When treating Obstructive Steep Apnea-Hypopnea Syndrome (OSAHS) several alternatives for standard (manual) continuous positive airway pressure (CPAP) titration are feasible. A practical alternative is titration without polysomnography during an afternoon nap (Nap-titration). The aim of the present s

  9. Constructing Marxism: Karl Kautsky and the French Revolution

    DEFF Research Database (Denmark)

    Nygaard, Bertel

    2009-01-01

    Karl Kautsky's writings on the French Revolution were crucial to the construction not only of the Marxist interpretation of the Revolution, which was perhaps the most important reference point for the historiography of that event during the 20th century, but even of Marxism itself as a comprehens......Karl Kautsky's writings on the French Revolution were crucial to the construction not only of the Marxist interpretation of the Revolution, which was perhaps the most important reference point for the historiography of that event during the 20th century, but even of Marxism itself...

  10. Mozart, Karl Barth, og den kristne troslæren

    DEFF Research Database (Denmark)

    Petersen, Nils Holger

    2010-01-01

    En diskussion af Karl Barths teologiske brug af W.A.Mozart i den kirchliche Dogmatik med kontekstuel inddragelse af en til en vis grad tilsvarende overordnet diskussion af Mozart, skrevet af en samtidig musiker, den fremtrædende Mozart-dirigent Ferenc Fricsay. ......En diskussion af Karl Barths teologiske brug af W.A.Mozart i den kirchliche Dogmatik med kontekstuel inddragelse af en til en vis grad tilsvarende overordnet diskussion af Mozart, skrevet af en samtidig musiker, den fremtrædende Mozart-dirigent Ferenc Fricsay. ...

  11. Irene K. Fischer (1907-2009)

    Science.gov (United States)

    Morrison, Foster; Chovitz, Bernard; Fischer, Michael M. J.

    2010-05-01

    Irene Kaminka Fischer, a prominent geodesist whose career spanned the years 1952-1977, died on 22 October 2009 at the age of 102 at an assisted living facility in Brighton, Mass. Born in Vienna, Austria, on 27 July 1907, Irene grew up there; graduating with a degree in mathematics from the Vienna Institute of Technology; and met and married her husband, Eric, a noted geographer. In 1939, the Fischers fled Nazi Austria, first to Palestine, and by 1941 had relocated to the United States. During the next 11 years, Irene worked at various jobs, as well as playing the role of mother to her son and daughter. But when her daughter was ready for college, she began to look for a position that would fully utilize her considerable talents in mathematics. She found a perfect fit at her husband's federal agency, the U.S. Army Map Service (AMS). Her entire career in geodesy was spent with that organization and its successors (currently the National Geospatial-Intelligence Agency (NGA)). Hired as a mathematician, she eventually was promoted to chief of the Geoid Branch in the Geodesy Division. She retained that position until her retirement in 1977.

  12. Fischer-Tropsch synthesis. Development and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Schaub, G.; Rohde, M.; Mena Subiranas, A. [Karlsruhe Univ. (Germany). Engler-Bunte-Institut

    2006-07-01

    Production of synthetic hydrocarbons via Fischer-Tropsch (FT) synthesis has the potential to produce high-value automotive fuels and petrochemicals from fossil and renewable sources. The availability of cheap natural gas and solid raw materials like coal and biomass has given momentum to synthesis technologies first developed in the mid-twentieth century. The present paper summarizes the fundamentals and describes some general aspects regarding driving forces, catalyst and reaction, synthesis reactor, and overall process. In this way, it indicates the context of present and future developments. Worldwide plant capacities will increase significantly in the next future, with natural gas favored as feedstock. Substitution of petroleum as well as production of improved products (like automotive fuels) are the most significant incentives. Energy loss and additional fossil CO{sub 2} emissions caused by the conversion process will be a problem in extended applications with fossil feedstocks. The current R and D activities worldwide, in all areas related to Fischer-Tropsch synthesis, will contribute to further process improvements and extended applications. (orig.)

  13. Hannah Arendt and Karl Jaspers: The Time of Friendship

    Science.gov (United States)

    Nixon, Jon

    2016-01-01

    This paper provides an introduction to the enduring friendship between Hannah Arendt and Karl Jaspers. It shows how their intellectual development as public educators was sustained by their ongoing dialogue which flourished not in spite of but because of their huge differences of circumstance and personality. This friendship between two renowned…

  14. Hannah Arendt and Karl Jaspers: The Time of Friendship

    Science.gov (United States)

    Nixon, Jon

    2016-01-01

    This paper provides an introduction to the enduring friendship between Hannah Arendt and Karl Jaspers. It shows how their intellectual development as public educators was sustained by their ongoing dialogue which flourished not in spite of but because of their huge differences of circumstance and personality. This friendship between two renowned…

  15. "Art, Imagination, Storytelling": An Interview with Karl Kroeber

    Science.gov (United States)

    Mallick, Michael

    2012-01-01

    This article presents an interview with Karl Kroeber that was originally published in "English Department Updates" (Fall 2009), a semiannual alumni newsletter of the Columbia University Department of English & Comparative Literature. In this interview, Kroeber, who taught at Columbia for 57 years, discusses the range of courses he…

  16. Chef's Signature - Karl Breen, Locks Brasserie, Dublin : Video

    OpenAIRE

    2015-01-01

    12 Hour Octopus, Black Garlic, Calamansi Mayo, Tamarind and Salted Celeriac is one of the dishes on Karl Breen's menu at Locks Brasserie in Dublin, and it's a dish that shows a cook in control of his art. Reproduced with kind permission from John & Sally McKenna. 3.16 mins

  17. Kokast ja Eesti Naisest / Karl Martin Sinijärv

    Index Scriptorium Estoniae

    Sinijärv, Karl Martin, 1971-

    2006-01-01

    Sisaldab retsepte: Ilmar Laabani lintnuudlid põdralihaga ; Jan Kausi krevetipasta ; Kauksi Ülle liharullid ; Jürgen Rooste banaanikana ; KMSi [Karl Martin Sinijärve] öine lugemisliud ; Asko Künnapi suvikõrvits ; Ilmar Laabani Margarita

  18. KARL MAYER——We Care about Your Future

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    As one of the leading manufacturers of warp knitting and warp preparation machines,KARL MAYER will be presenting at this year's ITMA 2011 in Barcelona.For the first time,all the company's business units will be represented on the same stand in hall 3,stand B 153-157,on an area of 1400 square-meter.

  19. Karl Popper and Jean Piaget: A Rationale for Constructivism

    Science.gov (United States)

    Harlow, Steve; Cummings, Rhoda; Aberasturi, Suzanne M.

    2006-01-01

    The current faddish use of the term constructivism has taken on as many different definitions as the number of people attempting to define it. This essay clarifies the meaning of constructivism through an examination of Karl Popper's and Jean Piaget's theories. The authors provide a rationale for the use of Popper's paradigm of "Three Worlds" and…

  20. The Reference Process and the Philosophy of Karl Popper.

    Science.gov (United States)

    Neill, S. D.

    1985-01-01

    Two aspects of Karl Popper's philosophy are applied to reference process: process is viewed as series of problem-solving situations amenable to analysis using Popper's problem-solving schema. Reference interview is analyzed in context of Popper's postulate that books contain autonomous world of ideas existing apart from mind of knower. (30…

  1. The dangerous misconceptions of Sir Karl Raimund Popper

    CERN Document Server

    Svozil, K

    2002-01-01

    Insofar as Sir Karl Raimund Popper's writings deal with political statements, they are evident; yet insofar as they deal with scientific issues, they are incorrect and misleading. If applied to the concrete implementation of science, such as distribution of research funds and (peer) review, they would seriously hamper progress.

  2. Karl XII rootsi kirjanduses / Anu Saluäär

    Index Scriptorium Estoniae

    Saluäär, Anu, 1948-

    2008-01-01

    Valikuline ülevaade Karl XII-st rootsi kirjanduses: Israel Holmström, Esaias Tegner, Zacharias Topelius, Carl Snoilsky, Anders Fryxell, Verner von Heidenstam, Harald Hiärne, Frans G. Bengtsson. Sisaldab märkusi joonealustes viidetes

  3. Surface Titrations of Perlite Suspensions.

    Science.gov (United States)

    Alkan; Do

    1998-11-01

    The surface charge behaviour of unexpanded and expanded perlite samples in KNO3 and NaCl solutions were investigated as a function of pH and ionic strength. The solutions of KNO3 and NaCl ranging from 10(-3) to 1.0 M were used. The potentiometric titration method was used to determine the surface charge of perlite samples. It was confirmed that the perlite samples had no the point of zero charge and was negatively charged in the pH range of 3-10. The double extrapolation method was used for determining the intrinsic equilibrium constants for simple ionization and complex ionization reactions. The values obtained are pKinta2 = 2.5 and p*KintK+ = 2.3 in KNO3 solutions and pKinta2 = 3.0 and p*KintNa+ = 2.4 in NaCl solutions for unexpanded perlite, and pKinta2 = 2.6 and p*KintK+ = 2.4 in KNO3 solutions and pKinta2 = 2.7 and pKintNa+ = 2.4 in NaCl solutions for expanded perlite. Copyright 1998 Academic Press.

  4. Determination of titratable acidity in white wine

    Directory of Open Access Journals (Sweden)

    Rajković Miloš B.

    2007-01-01

    Full Text Available The amount of titration acid in must is in the largest number of cases with in the range 5.0-8.0 g/dm3. Wines, as a rule, contain less acids than must, and according to Regulations, titratable acidity is in the range of 4.0-8.0 g/dm3 expressed in tartaric acid, because a part of tartaric acid is deposited in the form of salts (tartar or argol during alcohol fermentation. For wines that contain less than 4 g/dm3 of titratable acids there arises a suspicion about their origin, that is, that during the preparation some illegal acts were done. Because of that, the aim of this paper is to determine titratable acidity in white wine, using standard methods of determination, which are compared with the results received by potentiometric titration using ion-selective electrode. According to the received results it can be seen that wine titration with indicator gives sufficient reliable values of wine titration acidity. However, as potentiometric titration at pH value 7.00 is more reliable and objective method, the values of titratable acids content in wine, expressed through tartaric acid, are given according to this result. The analysis of differential potentiometric curves shows that these curves can give us an answer to the question of the presence of a larger amount of other nonorganic substances, which have already existed in wine. However, none of the used methods gives absolutely reliable answer what substances are present in analysed samples.

  5. Fly ash zeolite catalyst support for Fischer-Tropsch synthesis

    Science.gov (United States)

    Campen, Adam

    This dissertation research aimed at evaluating a fly ash zeolite (FAZ) catalyst support for use in heterogeneous catalytic processes. Gas phase Fischer-Tropsch Synthesis (FTS) over a fixed-bed of the prepared catalyst/FAZ support was identified as an appropriate process for evaluation, by comparison with commercial catalyst supports (silica, alumina, and 13X). Fly ash, obtained from the Wabash River Generating Station, was first characterized using XRD, SEM/EDS, particle size, and nitrogen sorption techniques. Then, a parametric study of a two-step alkali fusion/hydrothermal treatment process for converting fly ash to zeolite frameworks was performed by varying the alkali fusion agent, agent:flyash ratio, fusion temperature, fused ash/water solution, aging time, and crystallization time. The optimal conditions for each were determined to be NaOH, 1.4 g NaOH: 1 g fly ash, 550 °C, 200 g/L, 12 hours, and 48 hours. This robust process was applied to the fly ash to obtain a faujasitic zeolite structure with increased crystallinity (40 %) and surface area (434 m2/g). Following the modification of fly ash to FAZ, ion exchange of H+ for Na+ and cobalt incipient wetness impregnation were used to prepare a FTS catalyst. FTS was performed on the catalysts at 250--300 °C, 300 psi, and with a syngas ratio H2:CO = 2. The HFAZ catalyst support loaded with 11 wt% cobalt resulted in a 75 % carbon selectivity for C5 -- C18 hydrocarbons, while methane and carbon dioxide were limited to 13 and 1 %, respectively. Catalyst characterization was performed by XRD, N2 sorption, TPR, and oxygen pulse titration to provide insight to the behavior of each catalyst. Overall, the HFAZ compared well with silica and 13X supports, and far exceeded the performance of the alumina support under the tested conditions. The successful completion of this research could add value to an underutilized waste product of coal combustion, in the form of catalyst supports in heterogeneous catalytic processes.

  6. Assessment of the Extracts of Centaurea tchihatcheffii Fischer for ...

    African Journals Online (AJOL)

    Erah

    Fischer & C.A. Meyer (Asteraceae) for their anti-inflammatory and analgesic activities in male Swiss albino mice. Methods: .... conditions, maintained on standard pellet diet and given water ad ..... Edema and cell infiltration in the phorbol ester.

  7. Kuninganna Kristiina ning kunungas Karl XI : rootsiaegsed portreed raekojas = Queen Christina and King Karl XI : portraits of the Swedish period in the Town Hall / Pia Ehasalu

    Index Scriptorium Estoniae

    Ehasalu, Pia, 1964-

    2004-01-01

    Kuninganna Kristiina portreest lapsena (1638). Arvatav autor: Rootsi tolleaegne õuekunstnik Jacob Heinrich Elbfas või tema töökoda. Rootsi kuninga Karl XI noorpõlveportreest (1670). Autor: Karl XI õuekunstnik David Klöcker Ehrenstrahl (1628-1698)

  8. Kuninganna Kristiina ning kunungas Karl XI : rootsiaegsed portreed raekojas = Queen Christina and King Karl XI : portraits of the Swedish period in the Town Hall / Pia Ehasalu

    Index Scriptorium Estoniae

    Ehasalu, Pia, 1964-

    2004-01-01

    Kuninganna Kristiina portreest lapsena (1638). Arvatav autor: Rootsi tolleaegne õuekunstnik Jacob Heinrich Elbfas või tema töökoda. Rootsi kuninga Karl XI noorpõlveportreest (1670). Autor: Karl XI õuekunstnik David Klöcker Ehrenstrahl (1628-1698)

  9. [Karl Jaspers and the challenges of social psychiatry].

    Science.gov (United States)

    Jäger, Markus; Lang, Fabian U; Becker, Thomas

    2015-01-01

    Karl Jaspers, in his book "General Psychopathology", argued for methodological pluralism rather than theoretical dogmatism. He formulated a methodological order of psychopathology with a distinction between "explanation" (objective psychopathology) and "understanding" (subjective psychopathology, psychopathology of meaning). The latter approach focused on patients' subjective experience and biographical issues. Karl Jaspers emphasised social factors in the genesis and course of mental disorders. Following a multiperspective concept, from Jaspers' viewpoint social psychiatry should consider itself of equal importance with biological and psychotherapeutic psychiatry. Therefore, uncritical generalization of one of these perspectives should be avoided. Personalized psychiatry, apart from searching biological markers to tailor treatment should identify psychosocial factors and subjective meaning. Concepts of recovery should not ignore biological foundations in mental disorders.

  10. 1st Karl Schwarzschild Meeting on Gravitational Physics

    CERN Document Server

    Kaminski, Matthias; Mureika, Jonas; Bleicher, Marcus

    2016-01-01

    These proceedings collect the selected contributions of participants of the First Karl Schwarzschild Meeting on Gravitational Physics, held in Frankfurt, Germany to celebrate the 140th anniversary of Schwarzschild's birth. They are grouped into 4 main themes: I. The Life and Work of Karl Schwarzschild; II. Black Holes in Classical General Relativity, Numerical Relativity, Astrophysics, Cosmology, and Alternative Theories of Gravity; III. Black Holes in Quantum Gravity and String Theory; IV. Other Topics in Contemporary Gravitation. Inspired by the foundational principle ``By acknowledging the past, we open a route to the future",  the week-long meeting, envisioned as a forum for exchange between scientists from all locations and levels of education, drew participants from 15 countries across 4 continents. In addition to plenary talks from leading researchers, a special focus on young talent was provided, a feature underlined by the Springer Prize for the best student and junior presentations.

  11. Karl Raimund Popper: Problem Neopositivistik dan Teori Kritis Falsifikasi

    Directory of Open Access Journals (Sweden)

    M. Syamsul Huda

    2014-01-01

    Full Text Available Karl Popper once criticizes the positivistic paradigm by means of what he calls the theory of falsification. To him, the positivistic paradigm constitutes a failure simply because it cannot distinguish between science and prude science, that is, between empirical method and non-empirical method. In the scientific knowledge, empirical science, mathematics and logic must be differentiated, something that the positivistic paradigm has failed to do. This paradigm furthermore, did not have a clear picture what logic-based science is, empirical knowledge and psychology of knowledge. It also fails to properly understand knowledge that springs from tradition, emotion, authority and so forth. All positivistic paradigms such as that of Karl Max’s Historicism, Freud’s theory of Psycho Analysis, Adler’s theory of Individual Analysis and Newton’s theory of Gravitation fall into this trap of failure.

  12. Architecture and Art Regulations for Karl Marx Street

    Directory of Open Access Journals (Sweden)

    Alla Mironenko

    2015-08-01

    Full Text Available The architecture and art regulations for Karl Marx Street and adjoining territories have been worked out for the Committee for town planning of the Irkutsk city administration. Basic provisions: facades of buildings and structures, outdoor advertising and information facilities, artistic illumination of buildings, elements of land improvements. The main principle is to preserve historical appearance and to create a contemporary and comfortable environment.

  13. End-point construction and systematic titration error in linear titration curves-complexation reactions

    NARCIS (Netherlands)

    Coenegracht, P.M.J.; Duisenberg, A.J.M.

    1975-01-01

    The systematic titration error which is introduced by the intersection of tangents to hyperbolic titration curves is discussed. The effects of the apparent (conditional) formation constant, of the concentration of the unknown component and of the ranges used for the end-point construction are consid

  14. A generalized approach for the calculation and automation of potentiometric titrations Part 2. Redox Titrations

    NARCIS (Netherlands)

    Stur, J.; Bos, M.; van der Linden, W.E.

    1984-01-01

    The very fast calculation procedure described earlier is applied to calculate the titration curves of complicated redox systems. The theory is extended slightly to cover inhomogeneous redox systems. Titrations of iodine or 2,6-dichloroindophenol with ascorbic acid are described. It is shown that cor

  15. Titratable Acidity and Alkalinity of Red Soil Surfaces

    Institute of Scientific and Technical Information of China (English)

    SHAOZONG-CHEN; HEQUN; 等

    1993-01-01

    The surfaces of red soils have an apparent amphoteric character,carrying titratable acidity and titratable alkalinity simultaneously.The titratable acidity arises from deprotonation of hydroxyl groups of hydrous oxide-type surfaces and dissociation of weak-acid functional groups of soil organic matter,while the titratable alkalinity is derived from release of hydroxyl groups of hydrous oxide-type surfaces.The titratable acidity and titratable alkalinity mainly depended on the composition and content of iron and aluminum oxides in the soils.The results showed that the titratable acidity and titratable alkalinity were in significantly positive correlation not only with the content of amorphous aluminum oxide(Alo) and iron oxide(Feo) extracted with acid ammonium oxalate solution,free iron oxide(Fed) extracted with sodium dithionite-citrate-bicarbonate(DCB) and clays,but also with the zero point of charge (ZPC) of the samples.Organic matter made an important contribution to the titratable acidity.the titratable alkalinity was closely correlated with the amount of fluoride ions adsorbed.The titratable acidity and titratable alkalinity of red soils were influenced by parent materials,being in the order of red soil derived from basalt> that from tuff> that from granite.The titratable acidity and titratable alkalinity ware closely related with origination of the variable charges of red soils,and to a certain extent were responsible for variable negative and positive charges of the soils.

  16. Natural Monocrystalline Pyrite as Sensor for Potentiometric Redox Titrations. Part I. Titrations with Permanganate

    Directory of Open Access Journals (Sweden)

    B. V. Vukanovic

    2002-04-01

    Full Text Available Results obtained in potentiometric titrations of Fe(II, Mn(II, Fe(CN64-, C2O42- and As(III with standard potassium permanganate solution, are presented. The titration end point (TEP was detected with a universal electrode whose sensor is natural crystalline pyrite. The titrations of As(III were carried out in HCl (1.2 M and H2SO4 solutions (0.1- 4.5 M, whereas oxalate was determined in H2SO4 (0.1-4.5 M. Iron(II and hexacyanoferrate(II were titrated in H2SO4 and also in H3PO4 solutions (0.1-4.5 M. The titrations of Mn(II were performed in H2P2O72- media at pH 4.0, 5.0, 6.0 and 7.0. The results obtained by using the pyrite electrode were compared with those obtained by the application of a Pt-electrode, and good agreement, reproducibility and accuracy were obtained. The potentials in the course of the titration and at the end-point (TEP are rapidly established. The potential changes at the TEP ranged from 90 to 330 mV/0.1 mL, depending on the titrated system. The highest changes were observed in titrations of Fe(II in H3PO4 (240-330 mV/0.1 mL. Reversed titrations were also performed and accurate and reproducible results were obtained.

  17. Isothermal Titration Calorimetry in the Student Laboratory

    Science.gov (United States)

    Wadso, Lars; Li, Yujing; Li, Xi

    2011-01-01

    Isothermal titration calorimetry (ITC) is the measurement of the heat produced by the stepwise addition of one substance to another. It is a common experimental technique, for example, in pharmaceutical science, to measure equilibrium constants and reaction enthalpies. We describe a stirring device and an injection pump that can be used with a…

  18. Isothermal Titration Calorimetry in the Student Laboratory

    Science.gov (United States)

    Wadso, Lars; Li, Yujing; Li, Xi

    2011-01-01

    Isothermal titration calorimetry (ITC) is the measurement of the heat produced by the stepwise addition of one substance to another. It is a common experimental technique, for example, in pharmaceutical science, to measure equilibrium constants and reaction enthalpies. We describe a stirring device and an injection pump that can be used with a…

  19. El racionalismo crítico de Karl Popper

    Directory of Open Access Journals (Sweden)

    Luis María Delio Machado

    2015-10-01

    Full Text Available El presente artículo, pretende acercar algunos de los aspectos más importantes del pensamiento de uno de los filósofos más destacados de nuestro tiempo: Sir Karl Popper. Su presencia atraviesa nuestro siglo, presentándose como una de las voces visionarias y anticipadoras que se alzaron críticamente, contra toda actitud o acción que estuviese fundada en lo dogmático y que tuviese como finalidad, el olvido o la superación del individuo, aunque dicho olvido estuviese "justificado" por oraculares "bienes o fines superiores". (... 

  20. Karl Nagel : Pain things = Pain things / Eha Komissarov

    Index Scriptorium Estoniae

    Komissarov, Eha, 1947-

    2007-01-01

    Maali- ja videokunstnik Karl Nagelist kui probleemsest nüüdisaegsest kunstnikust, kes võtab provokatiivseid positsioone ideoloogiate ja poliitika küsimustes. Tema kunstnikupositsioon keerleb terrorismi, fašismi ja natsionalismi ümber, dissidendi positsioonile asununa on ta käsitlenud surma ja vägivalla teemat (Tšetšeenia sõda) ja üritanud sõna võtta ka kodanikuvabaduste laiendamise nimel. Sotsiaalse tegelikkuse ja kunsti vastandlikkuse küsimuses on ta võtnud nulltoleratsi taotleva seisukoha, võrdlemata kunsti tegelikkusega

  1. Karl Nagel : Pain things = Pain things / Eha Komissarov

    Index Scriptorium Estoniae

    Komissarov, Eha, 1947-

    2007-01-01

    Maali- ja videokunstnik Karl Nagelist kui probleemsest nüüdisaegsest kunstnikust, kes võtab provokatiivseid positsioone ideoloogiate ja poliitika küsimustes. Tema kunstnikupositsioon keerleb terrorismi, fašismi ja natsionalismi ümber, dissidendi positsioonile asununa on ta käsitlenud surma ja vägivalla teemat (Tšetšeenia sõda) ja üritanud sõna võtta ka kodanikuvabaduste laiendamise nimel. Sotsiaalse tegelikkuse ja kunsti vastandlikkuse küsimuses on ta võtnud nulltoleratsi taotleva seisukoha, võrdlemata kunsti tegelikkusega

  2. Karl pearson the scientific life in a statistical age

    CERN Document Server

    Porter, Theodore M

    2010-01-01

    Karl Pearson, founder of modern statistics, came to this field by way of passionate early studies of philosophy and cultural history as well as ether physics and graphical geometry. His faith in science grew out of a deeply moral quest, reflected also in his socialism and his efforts to find a new basis for relations between men and women. This biography recounts Pearson's extraordinary intellectual adventure and sheds new light on the inner life of science. Theodore Porter's intensely personal portrait of Pearson extends from religious crisis and sexual tensions to metaphysical and even m

  3. Brauer-Buschke-Fischer keratoderma associated with two malignancies

    Directory of Open Access Journals (Sweden)

    C Sujatha Vinod

    2012-01-01

    Full Text Available Hereditary punctuate palmoplantar keratoderma is a rare autosomal dominantly inherited condition with variable penetrance. We report a case of a 65-year-old manual laborer who presented with multiple asymptomatic hyperkeratotic lesions on both palms and soles of about 45-year duration, which was diagnosed as Brauer-Buschke-Fischer keratoderma and was associated with squamous cell carcinoma of chest wall and ethmoidal carcinoma. This case is being presented for its rarity and the association of Brauer-Buschke-Fischer keratoderma with two malignancies in a single individual.

  4. Titration Calorimetry Standards and the Precision of Isothermal Titration Calorimetry Data

    Science.gov (United States)

    Baranauskienė, Lina; Petrikaitė, Vilma; Matulienė, Jurgita; Matulis, Daumantas

    2009-01-01

    Current Isothermal Titration Calorimetry (ITC) data in the literature have relatively high errors in the measured enthalpies of protein-ligand binding reactions. There is a need for universal validation standards for titration calorimeters. Several inorganic salt co-precipitation and buffer protonation reactions have been suggested as possible enthalpy standards. The performances of several commercial calorimeters, including the VP-ITC, ITC200, and Nano ITC-III, were validated using these suggested standard reactions. PMID:19582227

  5. An Olfactory Indicator for Acid-Base Titrations.

    Science.gov (United States)

    Flair, Mark N.; Setzer, William N.

    1990-01-01

    The use of an olfactory acid-base indicator in titrations for visually impaired students is discussed. Potential olfactory indicators include eugenol, thymol, vanillin, and thiophenol. Titrations performed with each indicator with eugenol proved to be successful. (KR)

  6. Karl Barth’s epistemology: A critical appraisal

    Directory of Open Access Journals (Sweden)

    Daniël P. Veldsman

    2007-05-01

    Full Text Available Can the great 20th century systematic theologian Karl Barth justify the fundamental beliefs he holds regarding the priority of God’s revelation in Jesus Christ as put forward in his impressive and comprehensive Kirchliche Dogmatik? Is it enough and thus theologically justifiable to simply state in the words of Barth that the best theology would need no advocates: it would prove itself? In my appraisal of Barth’s epistemological stance, I would like to argue in this article that his stance in the first place, does not only lead to a total isolation of theological reflection, but secondly through his highly exclusive claim, takes on the character of a personal religious credo expanded into a comprehensive doctrine beyond any form of control, and ultimately thirdly, becomes methodologically in essence a specifically Barthian theology from below. Wenn die Theologie sich eine Wissenschaft nennen lässt oder selber nennt, so kann sie damit keinerlei Verpflictung übernehmen, sich an den für andere Wissenschaften gültigen Massstäbem messen zu lassen. (Karl Barth 1947:8

  7. Telephone titration of heart failure medications.

    Science.gov (United States)

    Steckler, Anne E; Bishu, Kalkidan; Wassif, Heba; Sigurdsson, Gardar; Wagner, Judy; Jaenicke, Connie; Vats, Shashank; Rector, Thomas; Anand, Inder S

    2011-01-01

    In clinical practice, heart failure (HF) medications are underused and prescribed at lower than recommended doses. Telephone care is an option that could help to titrate HF medication in a timely manner. We describe our experience of a nurse-run, cardiologist- or nurse practitioner-supervised clinic to up-titrate HF medications via telephone. Patients with the diagnosis of HF, New York Heart Association classes I to III, were referred to a registered nurse-run, cardiologist-/nurse practitioner-supervised HF medication titration clinic. Clinical and medication data collected at enrollment to the clinic and at 3 to 6 months after optimization of HF medications in patients who did or did not reach the target doses were compared. Effect on left ventricular (LV) function was also evaluated. There were 79 patients in the evaluation: 64 with HF and LV systolic dysfunction (LVSD) and the remaining 15 with HF and preserved ejection fraction (EF). Seventy-two percent of patients with LVSD were on an angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB), and 61% were on a β-blocker at baseline, and this increased to 98% and 97%, respectively, after optimization. Target doses was achieved in 50% of patients for ACEI or ARB, and in 41% for β-blockers. The median time to optimization was 54 days (interquartile range, 20-97 days). The average number of phone calls at the time of optimization were 5.4 (SD, 3.7), and the average number of clinic visits was 1.9 (SD, 1.3). Reasons for not reaching the target doses included hypotension, hyperkalemia, and renal dysfunction for ACEI and bradycardia for β-blockers. Overall, the EF increased by 10% (SD, 10%) after 6 months, and 35% or greater in 42% of patients whose baseline EF was less than 35%. There were no adverse events related to the dose up-titration. Telephonic titration of HF medications was feasible and safe and was achieved in 97% patients on ACEI/ARB and β-blockers. Medication titration was

  8. German Astronomer Karl Menten Is 2007 Jansky Awardee

    Science.gov (United States)

    2007-06-01

    Associated Universities, Inc., (AUI) and the National Radio Astronomy Observatory (NRAO) have awarded the 2007 Karl G. Jansky Lectureship to Professor Karl M. Menten of the Max-Planck-Institute for Radioastronomy in Bonn, Germany. The Jansky Lectureship is an honor established by the trustees of AUI to recognize outstanding contributions to the advancement of astronomy. Karl M. Menten Professor Karl M. Menten CREDIT: NRAO/AUI Click on image for high-resolution file (433 KB) Professor Menten is an extraordinarily productive scientist whose research has improved our fundamental understanding in a number of areas of astronomy. He has studied the chemistry of molecular clouds from which new stars are formed, the process of star formation in our own Milky Way Galaxy and in the early Universe, and the outer atmospheres of stars nearing the end of their "normal" lives. In 1991, Menten used NRAO's 140-foot Telescope at Green Bank, West Virginia, to discover strong radio emission from methanol masers in star-forming regions. These masers amplify, or strengthen, radio emission the same way a laser amplifies visible-light emission. Menten developed the observation of these methanol masers into a powerful tool for studying the formation of stars much more massive than our Sun, because the strong maser emission points astronomers to the stellar birthplaces. In addition, Menten pioneered the use of ultra-high-resolution observations with NRAO's Very Long Baseline Array to observe masers to make precision determinations of the structure, size and dynamics of the Milky Way. Menten received his doctoral degree in 1987 from the University of Bonn, Germany. He then joined the Harvard-Smithsonian Center for Astrophysics, working there until 1996, when he became the Director for Millimeter and Submillimeter Astronomy at the Max-Planck-Institute for Radioastronomy. In addition to that position, he also has been a Professor for Experimental Astrophysics at the University of Bonn since

  9. BASELINE DESIGN/ECONOMICS FOR ADVANCED FISCHER-TROPSCH TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    None

    1998-04-01

    Bechtel, along with Amoco as the main subcontractor, developed a Baseline design, two alternative designs, and computer process simulation models for indirect coal liquefaction based on advanced Fischer-Tropsch (F-T) technology for the U. S. Department of Energy's (DOE's) Federal Energy Technology Center (FETC).

  10. God has moved. Long live the God! / Rene Fischer

    Index Scriptorium Estoniae

    Fischer, Rene

    2004-01-01

    Reklaamifirma Tank senine shveitslasest loovjuht Rene Fischer oma tööst ettevõttes, firma edukuse võimalikest põhjustest, olukorrast Baltimaade reklaamiturul, Läti reklaamifirma Bates/Red Cell loovjuhiks lahkumise põhjustest ning eesmärkidest uuel töökohal. Lisad: Other stuff; Technical data

  11. God has moved. Long live the God! / Rene Fischer

    Index Scriptorium Estoniae

    Fischer, Rene

    2004-01-01

    Reklaamifirma Tank senine shveitslasest loovjuht Rene Fischer oma tööst ettevõttes, firma edukuse võimalikest põhjustest, olukorrast Baltimaade reklaamiturul, Läti reklaamifirma Bates/Red Cell loovjuhiks lahkumise põhjustest ning eesmärkidest uuel töökohal. Lisad: Other stuff; Technical data

  12. Simulation models and designs for advanced Fischer-Tropsch technology

    Energy Technology Data Exchange (ETDEWEB)

    Choi, G.N.; Kramer, S.J.; Tam, S.S. [Bechtel Corp., San Francisco, CA (United States)

    1995-12-31

    Process designs and economics were developed for three grass-roots indirect Fischer-Tropsch coal liquefaction facilities. A baseline and an alternate upgrading design were developed for a mine-mouth plant located in southern Illinois using Illinois No. 6 coal, and one for a mine-mouth plane located in Wyoming using Power River Basin coal. The alternate design used close-coupled ZSM-5 reactors to upgrade the vapor stream leaving the Fischer-Tropsch reactor. ASPEN process simulation models were developed for all three designs. These results have been reported previously. In this study, the ASPEN process simulation model was enhanced to improve the vapor/liquid equilibrium calculations for the products leaving the slurry bed Fischer-Tropsch reactors. This significantly improved the predictions for the alternate ZSM-5 upgrading design. Another model was developed for the Wyoming coal case using ZSM-5 upgrading of the Fischer-Tropsch reactor vapors. To date, this is the best indirect coal liquefaction case. Sensitivity studies showed that additional cost reductions are possible.

  13. Overview of Fischer-Tropsch Synthesis in Slurry Reactors

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A brief review of Fischer-Tropsch synthesis specially in slurry reactors ispresented, covering reaction kinetics, activity and selectivity of catalysts, productdistribution, effects of process parameters, mass transfer and solubility of gas. Someimportant aspects of further research are proposed for improving both theories andproduction.

  14. Overview of Fischer-Tropsch Synthesis in Slurry Reactors

    Institute of Scientific and Technical Information of China (English)

    丁百全; 李涛; A.A.C.M.Beenackers; G.P.vanderLaan

    2000-01-01

    A brief review of Fischer-Tropsch synthesis specially in slurry reactors is presented, covering reaction kinetics, activity and selectivity of catalysts, product distribution, effects of process parameters, mass transfer and solubility of gas. Some important aspects of further research axe proposed for improving both theories and production.

  15. Alternative Fuel Research in Fischer-Tropsch Synthesis

    Science.gov (United States)

    Surgenor, Angela D.; Klettlinger, Jennifer L.; Yen, Chia H.; Nakley, Leah M.

    2011-01-01

    NASA Glenn Research Center has recently constructed an Alternative Fuels Laboratory which is solely being used to perform Fischer-Tropsch (F-T) reactor studies, novel catalyst development and thermal stability experiments. Facility systems have demonstrated reliability and consistency for continuous and safe operations in Fischer-Tropsch synthesis. The purpose of this test facility is to conduct bench scale Fischer-Tropsch (F-T) catalyst screening experiments while focusing on reducing energy inputs, reducing CO2 emissions and increasing product yields within the F-T process. Fischer-Tropsch synthesis is considered a gas to liquid process which reacts syn-gas (a gaseous mixture of hydrogen and carbon monoxide), over the surface of a catalyst material which is then converted into liquids of various hydrocarbon chain length and product distributions1. These hydrocarbons can then be further processed into higher quality liquid fuels such as gasoline and diesel. The experiments performed in this laboratory will enable the investigation of F-T reaction kinetics to focus on newly formulated catalysts, improved process conditions and enhanced catalyst activation methods. Currently the facility has the capability of performing three simultaneous reactor screening tests, along with a fourth fixed-bed reactor used solely for cobalt catalyst activation.

  16. Niobia-supported Cobalt Catalysts for Fischer-Tropsch Synthesis

    NARCIS (Netherlands)

    den Otter, J.H.

    2016-01-01

    In this thesis niobia has been shown to be an attractive support for application in Fischer-Tropsch catalysis at industrially relevant conditions without apparent deactivation up to at least 200 hours of operation. This proves that the level of potentially poisoning contaminants is sufficiently low

  17. Kinetic titration series with biolayer interferometry.

    Science.gov (United States)

    Frenzel, Daniel; Willbold, Dieter

    2014-01-01

    Biolayer interferometry is a method to analyze protein interactions in real-time. In this study, we illustrate the usefulness to quantitatively analyze high affinity protein ligand interactions employing a kinetic titration series for characterizing the interactions between two pairs of interaction patterns, in particular immunoglobulin G and protein G B1 as well as scFv IC16 and amyloid beta (1-42). Kinetic titration series are commonly used in surface plasmon resonance and involve sequential injections of analyte over a desired concentration range on a single ligand coated sensor chip without waiting for complete dissociation between the injections. We show that applying this method to biolayer interferometry is straightforward and i) circumvents problems in data evaluation caused by unavoidable sensor differences, ii) saves resources and iii) increases throughput if screening a multitude of different analyte/ligand combinations.

  18. Kinetic titration series with biolayer interferometry.

    Directory of Open Access Journals (Sweden)

    Daniel Frenzel

    Full Text Available Biolayer interferometry is a method to analyze protein interactions in real-time. In this study, we illustrate the usefulness to quantitatively analyze high affinity protein ligand interactions employing a kinetic titration series for characterizing the interactions between two pairs of interaction patterns, in particular immunoglobulin G and protein G B1 as well as scFv IC16 and amyloid beta (1-42. Kinetic titration series are commonly used in surface plasmon resonance and involve sequential injections of analyte over a desired concentration range on a single ligand coated sensor chip without waiting for complete dissociation between the injections. We show that applying this method to biolayer interferometry is straightforward and i circumvents problems in data evaluation caused by unavoidable sensor differences, ii saves resources and iii increases throughput if screening a multitude of different analyte/ligand combinations.

  19. Titration force microscopy on supported lipid bilayers.

    Science.gov (United States)

    Garcia-Manyes, Sergi; Gorostiza, Pau; Sanz, Fausto

    2006-01-01

    The use of chemically modified atomic force microscopy (AFM) probes allows us to measure the surface charges of supported planar lipid bilayers with high sensitivity through the force spectroscopy operation mode. By controlling the chemistry of the tip, we can perform a classical analytical chemistry titration where the titration agent is a weak acid (attached to the AFM tip) with the particularity of being performed in surface rather than in solution and, especially, at the nanometric scale. Thus, the AFM tip acts as a real "nanosensor". The approaching curves of the force plots reveal that electrostatic interactions between the tip and the supported membrane play a key role. Besides, the plot of the adhesion force (measured from the retracting curve of the force plots) versus pH displays a nonsigmoidal shape with a peak in the adhesion force attributed to high-energy hydrogen bonds. One of these peaks corresponds to the pKa of the surface under study and the other to the pKa of the titrating probe attached to the tip.

  20. Fischer-Tropsch Catalyst for Aviation Fuel Production

    Science.gov (United States)

    DeLaRee, Ana B.; Best, Lauren M.; Bradford, Robyn L.; Gonzalez-Arroyo, Richard; Hepp, Aloysius F.

    2012-01-01

    As the oil supply declines, there is a greater need for cleaner alternative fuels. There will undoubtedly be a shift from crude oil to nonpetroleum sources as a feedstock for aviation (and other transportation) fuels. The Fischer-Tropsch process uses a gas mixture of carbon monoxide and hydrogen which is converted into various liquid hydrocarbons; this versatile gas-to-liquid technology produces a complex product stream of paraffins, olefins, and oxygenated compounds such as alcohols and aldehydes. The Fischer-Tropsch process can produce a cleaner diesel oil fraction with a high cetane number (typically above 70) without any sulfur and aromatic compounds. It is most commonly catalyzed by cobalt supported on alumina, silica, or titania or unsupported alloyed iron powders. Cobalt is typically used more often than iron, in that cobalt is a longer-active catalyst, has lower water-gas shift activity, and lower yield of modified products. Promoters are valuable in improving Fischer-Tropsch catalyst as they can increase cobalt oxide dispersion, enhance the reduction of cobalt oxide to the active metal phase, stabilize a high metal surface area, and improve mechanical properties. Our goal is to build up the specificity of the Fischer-Tropsch catalyst while adding less-costly transition metals as promoters; the more common promoters used in Fischer-Tropsch synthesis are rhenium, platinum, and ruthenium. In this report we will describe our preliminary efforts to design and produce catalyst materials to achieve our goal of preferentially producing C8 to C18 paraffin compounds in the NASA Glenn Research Center Gas-To-Liquid processing plant. Efforts at NASA Glenn Research Center for producing green fuels using non-petroleum feedstocks support both the Sub-sonic Fixed Wing program of Fundamental Aeronautics and the In Situ Resource Utilization program of the Exploration Technology Development and Demonstration program.

  1. Efficacy of split night CPAP titration in moderate and severe obstructive sleep apnea syndrome patients

    Directory of Open Access Journals (Sweden)

    Shereen Farghaly

    2016-01-01

    Conclusion: Split night sleep study is more commonly associated with unsuccessful CPAP titration than full night titration but successful titration could be obtained during split night titration in patients with severe AHI >36.5 event/h.

  2. Karl Polanyi og utopien om det fri marked

    DEFF Research Database (Denmark)

    Christiansen, Christian O.

    2012-01-01

    This article offers the first comprehensive introduction to Karl Polanyi’s The Great Transformation (TGT) from 1944 written in Danish. Relatively unnoticed by the time of its publication, TGT has since received widespread attention, especially after the rise of economic globalisation and of neo-l...... intellectual history, and its historical significance. The article introduces main themes of TGT and the reception of TGT. At the end, it briefly sketches a ‘Polanyian’ account of the world financial crisis of 2008.......-liberal policies. The thesis of TGT is that the great wars and crisis of Western civilization in the 20th century should be seen against the backdrop of the 19th century’s liberal civilisation. Polanyi argues that the attempt to create a liberal, free market world order was crucial for the later breakdown...

  3. Descriptive psychopathology, phenomenology, and the legacy of Karl Jaspers.

    Science.gov (United States)

    Häfner, Heinz

    2015-03-01

    With his early publications (1910-1913), Karl Jaspers created a comprehensive methodological arsenal for psychiatry, thus laying the foundation for descriptive psychopathology. Following Edmund Husserl, the founder of philosophical phenomenology, Jaspers introduced phenomenology into psychopathology as "static understanding," ie, the unprejudiced intuitive reproduction (Vergegenwärtigung) and description of conscious phenomena. In a longitudinal perspective, "genetic understanding" based on empathy reveals how mental phenomena arise from mental phenomena. Severance in understanding of, or alienation from, meaningful connections is seen as indicating illness or transition of a natural development into a somatic process. Jaspers opted for philosophy early. After three terms of law, he switched to studying medicine, came to psychopathology after very little training in psychiatry; to psychology without ever studying psychology; and to a chair in philosophy without ever studying philosophy. In the fourth and subsequent editions of his General Psychopathology, imbued by his existential philosophy, Jaspers partly abandoned the descriptive method.

  4. The origin of art according to Karl von den Steinen

    Directory of Open Access Journals (Sweden)

    Pierre Déléage

    2015-06-01

    Full Text Available Based on a study of the custom, adopted by ethnologists in the early 20th century, of asking Amerindians of Lowland South America to do drawings in pencil in their notebooks, I explore three forgotten fragments of the history of thinking: the intense debates on the origin of ornaments, opposing an evolutionist and a materialist approach at the end of the 19th century; the theories on the origin of figuration, which I show date back to the important work of Karl von den Steinen regarding the populations of central Brazil; and the publications of ethnologists’ portraits drawn by Indians of the lowlands of South America, a little-known tradition of reverse anthropology serving as a counterpoint to the study of the reception of Amerindian art in Western ethnological literature.

  5. Wie is die sondaar? Die beskouing van Karl Barth

    Directory of Open Access Journals (Sweden)

    F. J. van Zyl

    1994-01-01

    Full Text Available Who is the sinner? The view of Karl Barth The previous article dealt with Barth’s view of the knowledge and real essence of sin, while this one focus on his view of the human being as sinner. In accordance with his christological approach to all theological matters, Barth presents us with a description of the image and character of the sinner as mirrored by the obedient suffering and death of Jesus Christ on the cross in the place of all sinners of all times - past, present and future. The price that God paid in surrendering his only Son to such suffering, indicates the enormous guilt and baseness of every sinner. Every human being is utterly insolvent and can only be delivered from sin through God’s graceful remission of siru

  6. Sir Karl Popper and his philosophy of physics

    Science.gov (United States)

    Jammer, Max

    1991-12-01

    The eminent mathematical physicist Sir Hermann Bondi once said: “There is no more to science than its method, and there is no more to its method than Popper has said.” Indeed, many regard Sir Karl Raimund Popper the greatest philosopher of science in our generation. Much of what Popper “has said” refers to physics, but physicists, generally speaking, have little knowledge of what he has said. True, Popper's philosophy of science and, in particular, his realistic interpretation of quantum mechanics deviates considerably from the generally accepted doctrine. But as Popper, rightly I think, points out, it is precisely the proliferation of divergent theories which promotes the growth of scientific knowledge; it would be a danger for physics if physicists were dogmatically tied to a single theory or would not test their theory against alternatives. It is for this purpose that, on the occasion of the nonagenarian celebration of Popper's birthday, the present essay has been written.

  7. Karl Heinz Göller (1924-2009: in memoriam

    Directory of Open Access Journals (Sweden)

    Janez Stanonik

    2010-12-01

    Full Text Available The study is written in memory of Karl Heinz Göller, Professor of English literature at the Regensburg University, who died in Kelheim near Regensburg on 22nd April 2009. University of Regenburg was founded in 1967, and Göller was the first Dean of its Faculty of Philosophy. For more than 40 years he worked for the development of good contacts betwen the universities of Regensburg and Ljubljana. Since 2000 he was member of the Advisory Committee of the review Acta Neophilologica. In 1983 he founded the Society of German Mediaevalists, one of the leading societies of German scholars from the whole Germany, and was elected its first president. The study gives report on the development of Göller as a scholar, and his basic achievement in his research, pedagogical work and in university administration.

  8. Karl Lagerfeld打造天价礼盒

    Institute of Scientific and Technical Information of China (English)

    孙逸轩(编); Holly(译)

    2008-01-01

    著名的Dom Perignon不久前邀请到时装大师Karl Lagerfeld为英国Harrods百货设计了一款Dom Perignon Rose Vintages限量礼盒装。并已在Harrods百货公司开始出售。这款Dom Perignon Rose Vintages限量礼盒外型很似订制吉他盒,粉色蛇纹外表搭配闪耀的金属扣,整体感觉前卫、时髦,盒内衬有同色羔羊皮,并装有六只珍藏的精巧Dom Perignon Rose Vintages与三个香槟杯。

  9. Karl Popper: antes y después de Kyoto

    Directory of Open Access Journals (Sweden)

    Zanotti, Gabriel

    1999-06-01

    Full Text Available Not available.En su último libro sobre Karl Popper, Mariano Artigas plantea una hermenéutica revolucionaria: muestra que la ética de Popper es el fundamento de su epistemología, y que el fundamento de esa ética está lejos del «conjeturalismo» que suele atribuirse a Popper. Artigas analiza qué significa en Popper la «fe irracional en la razón» y utiliza, como fuente inédita, el dramático relato que hace Popper de su relación con W. W. Bartley, por primera vez, en Kyoto, en 1992. Sea cual fuere la opinión del lector, el libro de Artigas divide la hermenéutica de Popper en un antes y un después.

  10. Karl Heinrich Ulrichs: First Theorist of Erotic Age Orientation.

    Science.gov (United States)

    Janssen, Diederik F

    2017-01-01

    The nomination of Karl Heinrich Ulrichs (1825-1895) as the first theorist of homosexuality may be placed in the oblique light of his eligibility for the nomination as the first theorist of erotic age orientation. In Ulrichs's pamphlets, "man-manly" homosexuality emerged as a particular age orientation, with a subsequent typological breakdown that, importantly, blended gender orientation and age orientation. Into the early 20th century, erotic age orientation remained bound up with the classification and emancipation of what here was demarcated as Urningsliebe. Ulrichs's pioneering and shifting comments on age eventually fed into his legal model of consenting adults in private. They also provide a starting point for the historical understanding of the trope of "grooming pedophile" as it, arguably, crossfaded with that of the "seducing homosexual" after the latter's depsychiatricization across the Western world.

  11. Karl Marx e a Revolução Russa

    Directory of Open Access Journals (Sweden)

    Angelo Segrillo

    Full Text Available Resumo O artigo analisa a visão de Karl Marx sobre a possibilidade de ocorrência da revolução na Rússia. Inicialmente concentrando suas esperanças nos países da Europa Ocidental, onde o capitalismo estava mais desenvolvido, com o fracasso das revoluções de 1948 e da Comuna de Paris, Marx se volta para as possibilidades de revolução a partir do Leste, da Rússia, até ali considerada o bastião da reação. Suas ideias são expostas em correspondência com os próprios revolucionários russos. Essa trajetória intelectual de Marx é descrita a partir de seus próprios escritos.

  12. Karl Popper's Conception of Metaphysics and its Problems

    Directory of Open Access Journals (Sweden)

    Cláudia Ribeiro

    2014-08-01

    Full Text Available In this paper I intend to thoroughly analyse Karl Popper’s relation to metaphysics. I start with his first writings, where he states the differences between science, pseudoscience and metaphysics. I then describe how his thoughts on the subject evolved to culminate in his reflection on metaphysical research programmes and the need for a revival of natural philosophy. A major concern is Popper’s famous testability criterion to set apart science from non-science. I point at the problems of the conception of metaphysics as non-testable theories (which are similar to the problems of the conception of metaphysics as theories involving unobservables and, in order to avoid these problems, I propose to retain nothing but the traditional conception of metaphysics as the general theories about the nature of the world. This leads me to the conclusion that science is not only an empirical task but also, and in a very important sense, a speculative one.

  13. O marxismo antidogmático de Karl Korsch

    Directory of Open Access Journals (Sweden)

    Nildo Viana

    2013-06-01

    Full Text Available O presente artigo tematiza o marxismo de Karl Korsch, focalizando seu caráter não dogmático. A partir de um resgate do caráter crítico e revolucionário do marxismo de Marx, Korsch realiza uma crítica radical ao revisionismo e leninismo. Para tal, ele não só resgata o verdadeiro caráter da dialética marxista e da concepção materialista da história, como exige a coerência dessa concepção ao defender o princípio de aplicação dela a si mesma. Assim ele lança as bases de um marxismo não dogmático, para o qual é o vínculo com o proletariado que mostra o caráter do marxismo e não ideologias petrificadas. Abstract: This article thematizes Marxism of Karl Korsch, focusing on its non dogmatic. From a rescue of criticality and revolutionary Marxism of Marx, Korsch performs a radical critique of revisionism and Leninism. To do so, he not only rescues the true character of Marxist dialectics and materialist conception of history, as this concept requires consistency in defending the principle of applying it to herself. So he lays the foundations of a non-dogmatic Marxism, to which is the bond with the proletariat that shows the character of Marxism and not petrified ideologies. Key words: Marxism, dogmatism, criticism, historical materialism, dialectical.

  14. The \\c{hi}2-test, the Muon AMM and Karl R. Popper

    CERN Document Server

    Iurato, Giuseppe

    2013-01-01

    In this very brief note, we only wish to identify a simple but notable epistemological basis, concerning the Karl R. Popper philosophy of science thought, into the realm of the experimental proves of Fundamental Physics.

  15. Karl E. Mundt National Wildlife Refuge: Annual narrative report: Calendar year 1978

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Karl E. Mundt NWR outlines Refuge accomplishments during the 1978 calendar year. The report begins with an introduction to the Refuge and...

  16. Karl E. Mundt National Wildlife Refuge: Annual narrative report: Calendar year 1979

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Karl E. Mundt NWR outlines Refuge accomplishments during the 1979 calendar year. The report begins with an introduction to the Refuge and...

  17. Karl E. Mundt National Wildlife Refuge: Annual narrative report: Calendar year 1980

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Karl E. Mundt NWR outlines Refuge accomplishments during the 1980 calendar year. The report begins with an introduction to the Refuge and...

  18. Isothermal titration calorimetry and differential scanning calorimetry.

    Science.gov (United States)

    Holdgate, Geoff

    2009-01-01

    Isothermal titration [Holdgate (BioTechniques 31:164-184, 2001); Ward and Holdgate (Prog. Med. Chem. 38:309-376, 2001); O'Brien et al. (2001) Isothermal titration calorimetry of biomolecules. In: Harding, S. E. and Chowdhry, B. Z. (eds.), Protein-Ligand Interactions: Hydrodynamics and Calorimetry, A Practical Approach. Oxford University Press, Oxford, UK] and differential scanning calorimetry [Jelesarov and Bosshard (J. Mol. Recognit. 12:3-18, 1999); Privalov and Dragan (Biophys. Chem. 126:16-24, 2007); Cooper et al. (2001) Differential scanning microcalorimetry. In: Harding, S. E. and Chowdhry, B. Z. (eds.), Protein-Ligand Interactions: Hydrodynamics and Calorimetry, A Practical Approach. Oxford University Press, Oxford, UK] are valuable tools for characterising protein targets, and their interactions with ligands, during the drug discovery process. The parameters obtained from these techniques: triangle DeltaH, triangle DeltaG, triangle DeltaS, and triangle DeltaC (p), are properties of the entire system studied and may be composed of many contributions, including the binding reaction itself, conformational changes of the protein and/or ligand during complexation, changes in solvent organisation or other equilibria linked to the binding process. Dissecting and understanding these components, and how they contribute to binding interactions, is a critical step in the ability to design ligands that have high binding affinity for the target protein.

  19. Nonsmooth Newton method for Fischer function reformulation of contact force problems for interactive rigid body simulation

    DEFF Research Database (Denmark)

    Silcowitz, Morten; Niebe, Sarah Maria; Erleben, Kenny

    2009-01-01

    contact response. In this paper, we present a new approach to contact force determination. We reformulate the contact force problem as a nonlinear root search problem, using a Fischer function. We solve this problem using a generalized Newton method. Our new Fischer - Newton method shows improved...... qualities for specific configurations where the most widespread alternative, the Projected Gauss-Seidel method, fails. Experiments show superior convergence properties of the exact Fischer - Newton method....

  20. Codependency and Validating Spann-Fischer in The Women of Mashhad

    OpenAIRE

    2010-01-01

    Objective: The aim of this study is validating Spann-Fischer (codependency test) and investigating the "codependency" based on characteristics of the substance abuser wives. Methods: Spann-Fischer test normalize using a sample of 507 women. A sample contain of 204 women with addicted husbands who had referred to 33 qutting centers in Mashhad were analyzed and they also were used to validate the test. Results: The results confirm the validity and reliability of Spann-Fischer test, significant...

  1. Increasing titration speed by using an end paint anticipator device

    OpenAIRE

    2001-01-01

    A simple device is described for use in any titrations with the objective of rapidly locating the vicinity of the end point of a titration. The device stores inside about 10% of a 10 mL titrand solution. The titration itself proceeds with rapid addition of titrant until the end point is passed. The anticipator device now starts to rotate, using a dc motor, which is turned on by a micro-computer. The solution stored in the device is mixed with the already titrated solution and the property bei...

  2. Preliminary evidence of oxidation in standard oven drying of cotton: attenuated total reflectance/ Fourier transform spectroscopy, colorimetry, and particulate matter formation

    Science.gov (United States)

    Moisture is paramount to cotton fiber properties dictating harvesting, ginning, storage and spinning as well as others. Currently, oven drying in air is often utilized to generate the percentage of moisture in cotton fibers. Karl Fischer Titration another method for cotton moisture, has been compa...

  3. Testing the null hypothesis: the forgotten legacy of Karl Popper?

    Science.gov (United States)

    Wilkinson, Mick

    2013-01-01

    Testing of the null hypothesis is a fundamental aspect of the scientific method and has its basis in the falsification theory of Karl Popper. Null hypothesis testing makes use of deductive reasoning to ensure that the truth of conclusions is irrefutable. In contrast, attempting to demonstrate the new facts on the basis of testing the experimental or research hypothesis makes use of inductive reasoning and is prone to the problem of the Uniformity of Nature assumption described by David Hume in the eighteenth century. Despite this issue and the well documented solution provided by Popper's falsification theory, the majority of publications are still written such that they suggest the research hypothesis is being tested. This is contrary to accepted scientific convention and possibly highlights a poor understanding of the application of conventional significance-based data analysis approaches. Our work should remain driven by conjecture and attempted falsification such that it is always the null hypothesis that is tested. The write up of our studies should make it clear that we are indeed testing the null hypothesis and conforming to the established and accepted philosophical conventions of the scientific method.

  4. Centenary of Karl Jaspers's general psychopathology: implications for molecular psychiatry.

    Science.gov (United States)

    Thome, Johannes

    2014-01-01

    Modern molecular psychiatry benefits immensely from the scientific and technological advances of general neuroscience (including genetics, epigenetics, and proteomics). This "progress" of molecular psychiatry, however, will be to a degree "unbalanced" and "epiphytic" should the development of the corresponding theoretical frameworks and conceptualization tools that allow contextualization of the individual neuroscientific findings within the specific perspective of mental health care issues be neglected. The General Psychopathology, published by Karl Jaspers in 1913, is considered a groundbreaking work in psychiatric literature, having established psychopathology as a space of critical methodological self-reflection, and delineating a scientific methodology specific to psychiatry. With the advance of neurobiology and molecular neuroscience and its adoption in psychiatric research, however, a growing alienation between current research-oriented neuropsychiatry and the classical psychopathological literature is evident. Further, consensus-based international classification criteria, although useful for providing an internationally accepted system of reliable psychiatric diagnostic categories, further contribute to a neglect of genuinely autonomous thought on psychopathology. Nevertheless, many of the unsolved theoretical problems of psychiatry, including those in the areas of nosology, anthropology, ethics, epistemology and methodology, might be fruitfully addressed by a re-examination of classic texts, such as Jaspers's General Psychopathology, and their further development and adaptation for 21st century psychiatry.

  5. Falsifications and corroborations: Karl Popper's influence on systematics.

    Science.gov (United States)

    Helfenbein, Kevin G; DeSalle, Rob

    2005-04-01

    Over the last three decades, the philosophy of Karl Raimund Popper has had a strong influence on the field of systematic biology. Unequivocally, no other philosopher's work has had such an influence during this formative period in systematics. Much, but not all, of the early discourse on Popper and systematics dealt with the philosophical basis of systematics as a science. More recently Popper's work has been discussed in the systematics literature in relation to specific methodologies such as parsimony and maximum likelihood. In this paper, we provide the reader with a concise summary of Popper's ideas relevant to systematics, review the systematic literature invoking or declining Popper's importance to the field, and make a recommendation for the future course of philosophical thinking in systematics. We try to make clear various authors' interpretations of Popper's work and how those interpretations have impacted systematic thought. Although the reader may come away from this review with a clearer idea of Popper's relevance or lack thereof, our primary hope is that the reader will be compelled to question him- or herself about the philosophical basis of the systematic work that he or she does, and to delve into the literature herein cited. We begin by presenting a synopsis of Popper's philosophical views to allow those views to be placed in the context of systematics.

  6. Karl Marx and the Study of Media and Culture Today

    Directory of Open Access Journals (Sweden)

    Christian Fuchs

    2014-02-01

    Full Text Available The task of this paper discusses the role of Marx in analysing media, communica-tion and culture today. An analysis of three contemporary Cultural Studies works – Lawrence Grossberg’s monograph Cultural Studies in the Future Tense, John Hartley’s monograph Digital Futures for Cultural and Media Studies and Paul Smith’s edited volume The Renewal of Cultural Studies – shows that there is an agreement that the economy needs to be taken more into account by Cultural Studies, but disagreement on which approach should be taken and what the role of Karl Marx’s works shall be. The paper argues that Marx’s labour theory of value is especially important for critically analysing the media, culture and communica-tion. Labour is still a blind spot of the study of culture and the media, although this situation is slowly improving. It is maintained that the turn away from Marx in Cultural and Media Studies was a profound mistake that should be reverted. Only an engagement with Marx can make Cultural and Media Studies topical, politically relevant, practical and critical, in the current times of global crisis and resurgent critique.

  7. Karl Pearson and eugenics: personal opinions and scientific rigor.

    Science.gov (United States)

    Delzell, Darcie A P; Poliak, Cathy D

    2013-09-01

    The influence of personal opinions and biases on scientific conclusions is a threat to the advancement of knowledge. Expertise and experience does not render one immune to this temptation. In this work, one of the founding fathers of statistics, Karl Pearson, is used as an illustration of how even the most talented among us can produce misleading results when inferences are made without caution or reference to potential bias and other analysis limitations. A study performed by Pearson on British Jewish schoolchildren is examined in light of ethical and professional statistical practice. The methodology used and inferences made by Pearson and his coauthor are sometimes questionable and offer insight into how Pearson's support of eugenics and his own British nationalism could have potentially influenced his often careless and far-fetched inferences. A short background into Pearson's work and beliefs is provided, along with an in-depth examination of the authors' overall experimental design and statistical practices. In addition, portions of the study regarding intelligence and tuberculosis are discussed in more detail, along with historical reactions to their work.

  8. Isothermal Titration Calorimetry to Characterize Enzymatic Reactions.

    Science.gov (United States)

    Mazzei, Luca; Ciurli, Stefano; Zambelli, Barbara

    2016-01-01

    Isothermal titration calorimetry (ITC) is a technique that measures the heat released or absorbed during a chemical reaction as an intrinsic probe to characterize any chemical process that involves heat changes spontaneously occurring during the reaction. The general features of this method to determine the kinetic and thermodynamic parameters of enzymatic reactions (kcat, KM, ΔH) are described and discussed here together with some detailed applications to specific cases. ITC does not require any modification or labeling of the system under analysis, can be performed in solution, and needs only small amounts of enzyme. These properties make ITC an invaluable, powerful, and unique tool to extend the knowledge of enzyme kinetics to drug discovery. © 2016 Elsevier Inc. All rights reserved.

  9. Isothermal Titration Calorimetry of Chiral Polymeric Nanoparticles.

    Science.gov (United States)

    Werber, Liora; Preiss, Laura C; Landfester, Katharina; Muñoz-Espí, Rafael; Mastai, Yitzhak

    2015-09-01

    Chiral polymeric nanoparticles are of prime importance, mainly due to their enantioselective potential, for many applications such as catalysis and chiral separation in chromatography. In this article we report on the preparation of chiral polymeric nanoparticles by miniemulsion polymerization. In addition, we describe the use of isothermal titration calorimetry (ITC) to measure the chiral interactions and the energetics of the adsorption of enantiomers from aqueous solutions onto chiral polymeric nanoparticles. The characterization of chirality in nano-systems is a very challenging task; here, we demonstrate that ITC can be used to accurately determine the thermodynamic parameters associated with the chiral interactions of nanoparticles. The use of ITC to measure the energetics of chiral interactions and recognition at the surfaces of chiral nanoparticles can be applied to other nanoscale chiral systems and can provide further insight into the chiral discrimination processes of nanomaterials. © 2015 Wiley Periodicals, Inc.

  10. 100 anos da 'psicopatologia geral' de Karl Jaspers : Actas do Colóquio 100 Anos da 'Psicopatologia Geral' de Karl Jaspers

    OpenAIRE

    Teixeira, José A. Carvalho

    2014-01-01

    Publicam-se agora as Actas do Colóquio 100 ANOS DA ‘PSICOPATOLOGIA GERAL’ DE KARL JASPERS, realizado em 19 de Fevereiro de 2014 e organizado pelo Departamento de Psicologia Clínica e da Saúde do ISPA – Instituto Universitário.

  11. A Closer Look at Acid-Base Olfactory Titrations

    Science.gov (United States)

    Neppel, Kerry; Oliver-Hoyo, Maria T.; Queen, Connie; Reed, Nicole

    2005-01-01

    Olfactory titrations using raw onions and eugenol as acid-base indicators are reported. An in-depth investigation on olfactory titrations is presented to include requirements for potential olfactory indicators and protocols for using garlic, onions, and vanillin as acid-base olfactory indicators are tested.

  12. Differential Binding Models for Direct and Reverse Isothermal Titration Calorimetry.

    Science.gov (United States)

    Herrera, Isaac; Winnik, Mitchell A

    2016-03-10

    Isothermal titration calorimetry (ITC) is a technique to measure the stoichiometry and thermodynamics from binding experiments. Identifying an appropriate mathematical model to evaluate titration curves of receptors with multiple sites is challenging, particularly when the stoichiometry or binding mechanism is not available. In a recent theoretical study, we presented a differential binding model (DBM) to study calorimetry titrations independently of the interaction among the binding sites (Herrera, I.; Winnik, M. A. J. Phys. Chem. B 2013, 117, 8659-8672). Here, we build upon our DBM and show its practical application to evaluate calorimetry titrations of receptors with multiple sites independently of the titration direction. Specifically, we present a set of ordinary differential equations (ODEs) with the general form d[S]/dV that can be integrated numerically to calculate the equilibrium concentrations of free and bound species S at every injection step and, subsequently, to evaluate the volume-normalized heat signal (δQ(V) = δq/dV) of direct and reverse calorimetry titrations. Additionally, we identify factors that influence the shape of the titration curve and can be used to optimize the initial concentrations of titrant and analyte. We demonstrate the flexibility of our updated DBM by applying these differentials and a global regression analysis to direct and reverse calorimetric titrations of gadolinium ions with multidentate ligands of increasing denticity, namely, diglycolic acid (DGA), citric acid (CIT), and nitrilotriacetic acid (NTA), and use statistical tests to validate the stoichiometries for the metal-ligand pairs studied.

  13. Quantitative Analysis of Sulfate in Water by Indirect EDTA Titration

    Science.gov (United States)

    Belle-Oudry, Deirdre

    2008-01-01

    The determination of sulfate concentration in water by indirect EDTA titration is an instructive experiment that is easily implemented in an analytical chemistry laboratory course. A water sample is treated with excess barium chloride to precipitate sulfate ions as BaSO[subscript 4](s). The unprecipitated barium ions are then titrated with EDTA.…

  14. The coulometric titration of acids and bases in dimethylsulfoxide media

    NARCIS (Netherlands)

    Bos, M.; IJpma, S.T.; Dahmen, E.A.M.F.

    1976-01-01

    The coulometric titration of 20–200 μeq of acids and bases in DMSO media is described. In the titration of bases, the electro-oxidation of hydrogen at a platinized platinum electrode is used as the source of protons. The conditions for 100 % current efficiency at this electrode are low current

  15. Separation of Fischer-Tropsch from Catalyst by Supercritical Extraction.

    Energy Technology Data Exchange (ETDEWEB)

    Joyce, P.C.; Thies, M.C.

    1997-10-31

    The objective of this research project is to evaluate the potential of supercritical fluid (SCF) extraction for the recovery and fractionation of the wax product from the slurry bubble column (SBC) reactor of the Fischer-Tropsch (F-T) process. The wax, comprised mostly of branched and linear alkanes with a broad molecular weight distribution up to C{sub 100}, will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300{degrees}C. Initial work is being performed using n-hexane as the solvent.

  16. O pensamento epistemológico de Karl Popper

    Directory of Open Access Journals (Sweden)

    José Luiz dos Santos

    2007-01-01

    Full Text Available Desde a antiguidade, o critério de demarcação entre o que é ciência e o que não é ciência tem sido discutido. A noção que então se tinha de ciência coincidia com a busca do saber absoluto. Tornava-se necessária, para os pensadores gregos, entre eles, Aristóteles, Pitágoras e Descartes, a consolidação de uma distinção precisa entre o saber contingente e o saber necessário, pois o único discurso que poderia satisfazer às exigências do rigor científico era aquele que apontasse, nos fenômenos, conexões causais cuja necessidade pudesse ser demonstrada. Antes de Popper, o pensamento filosófico ocidental atravessou séculos tentando explicar por que nossas teorias frequentemente estavam erradas. Em sua obra fundamental, A Lógica da Pesquisa Científica, Karl Popper coloca em novos termos a discussão epistemológica ao demonstrar que o erro, em vez de ser um mal que pode ser evitado através do recurso a algum procedimento metodológico específico, constitui componente inevitável de qualquer teoria científica, sendo o motor pelo qual a ciência se move. Buscando captar a lógica do desenvolvimento da ciência, Popper inicia sua exposição destruindo aquele que talvez fosse, de todos os princípios filosóficos, o mais caro aos cientistas e à boa parte dos filósofos de seu tempo: o princípio da indução como método de procedimento científico. Neste artigo, abordam-se alguns dos principais tópicos do pensamento popperiano, como o princípio da indução, a concepção de ciência e a falseabilidade. Também se intenta aduzir alguns debates filosóficos, justapondo às opiniões de Popper e de críticos ao seu pensamento. A contestação aludida ao pensamento popperiano advém do professor Thomas S. Kuhn, da Princeton University. Kuhn objeta à opinião de Popper quando este afirma que o cientista é um solucionador de problemas. Para Kuhn, os cientistas são solucionadores de enigmas e não de problemas. Essa posi

  17. Coupling of glycerol processing with Fischer-Tropsch synthesis for production of liquid fuels

    DEFF Research Database (Denmark)

    Simonetti, D.A.; Rass-Hansen, Jeppe; Kunkes, E.L.

    2007-01-01

    % methanol, ethanol, and acetone, which can be separated from the water by distillation and used in the chemical industry or recycled for conversion to gaseous products. This integrated process has the potential to improve the economics of "green'' Fischer-Tropsch synthesis by reducing capital costs......Liquid alkanes can be produced directly from glycerol by an integrated process involving catalytic conversion to H-2/CO gas mixtures (synthesis gas) combined with Fischer-Tropsch synthesis. Synthesis gas can be produced at high rates and selectivities suitable for Fischer-Tropsch synthesis (H-2/CO......, acetone, and acetol. Fischer -Tropsch synthesis experiments at 548 K and 5 bar over a Ru-based catalyst reveal that water, ethanol, and acetone in the synthesis gas feed have only small effects, whereas acetol can participate in Fischer -Tropsch chain growth, forming pentanones, hexanones, and heptanones...

  18. 40 CFR 721.10103 - Naphtha (Fischer-Tropsch), C4-11-alkane, branched and linear.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Naphtha (Fischer-Tropsch), C4-11... Significant New Uses for Specific Chemical Substances § 721.10103 Naphtha (Fischer-Tropsch), C4-11-alkane... substance identified as naphtha (fischer-tropsch), C4-11-alkane, branched and linear (PMN P-04-235; CAS No...

  19. Titration procedure for low ethoxylated nonionic surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Buschmann, N. [Anorganisch-Chemisches Inst., Lehrstuhl fuer Analytische Chemie, Muenster Univ. (Germany); Huelskoetter, F. [Anorganisch-Chemisches Inst., Lehrstuhl fuer Analytische Chemie, Muenster Univ. (Germany)

    1997-01-01

    Highly lipophilic surfactants are frequently used as emulsifiers for preparing oil-in-water emulsions (e.g. coolants lubricants). Typical surfactants used for this purpose are low ethoxylated alcohols and ethoxylated alkylphenols. Due to the low degree of ethoxylation they cannot be analysed by conventional methods. The method described in this article is based on the introduction of an anionic group into the molecule by a derivatization reaction. The reaction product can be determined by conventional titration methods for anionic surfactants without any modification. The use of the new method for other nonionic surfactants like sorbitan esters, (ethoxylated) fatty acid amides or glycerol fatty acid partial esters is also described as well as the sample preparation for coolants lubricants. (orig.) [Deutsch] Lipophile Tenside werden haeufig zur Herstellung von Oel-in-Wasser-Emulsionen verwandt, wie sie beispielsweise in Kuehlschmiermitteln eingesetzt werden. Typische Vertreter dieser Tenside sind niedrig ethoxylierte Fettalkohole und Alkylphenole. Wegen ihres geringen Ethoxylierungsgrades koennen sie mit den konventionellen Methoden nicht analytisch bestimmt werden. Die hier beschriebene Analysenmethode beruht auf der Derivatisierung der Ethoxylate zu entsprechenden anionischen Tensiden (Ethersulfate). Diese koennen ohne weiteres mit den etablierten Titrationsverfahren bestimmt werden. Die Anwendung dieses neuen Verfahrens auf die Bestimmung anderer nichtionischer Tenside - Sorbitanester, (ethoxylierte) Fettsaeureamide und Partialglyceride - wird ebenso beschrieben wie die Probenvorbereitung fuer die Analyse von Kuehlschmiermitteln. (orig.)

  20. Titration of gold nanoparticles in phase extraction.

    Science.gov (United States)

    Cheng, Han-Wen; Schadt, Mark J; Zhong, Chuan-Jian

    2015-12-07

    In the organic-aqueous phase transfer process of gold nanoparticles, there are two types of distinctive interfaces involving hydrophilic and hydrophobic ligands, the understanding of which is important for the design of functional nanomaterials for analytical/bioanalytical applications and the control over the nanoparticles' nanoactivity and nanotoxicity in different phases. This report describes new findings of an investigation of the quantitative aspect of ligand ion pairing at the capping monolayer structure that drives the phase extraction of gold nanoparticles. Alkanethiolate-capped gold nanoparticles of 8 nm diameter with high size monodispersity (RSD ∼ 5%) were first derivatized by a ligand place exchange reaction with 11-mercaptoundecanoic acid to form a mixed monolayer shell consisting of both hydrophobic (-CH3) and hydrophilic (-COOH) groups. It was followed by quantitative titration of the resulting nanoparticles with a cationic species (-NR4(+)) in a toluene phase, yielding ion pairing of -NR4(+) and -COO(-) on part of the capping monolayer. Analysis of the phase extraction allowed a quantitative determination of the percentage of ion pairing and structural changes in the capping monolayer on the nanoparticles. The results, along with morphological characterization, are discussed in terms of the interfacial structural changes and their implications on the rational design of surface-functionalized nanoparticles and fine tuning of the interfacial reactivity.

  1. The Karl G. Jansky Very Large Array Sky Survey (VLASS)

    Science.gov (United States)

    Myers, Steven T.; Baum, S. A.; Chandler, C. J.

    2014-01-01

    The Karl G. Jansky Very Large Array is a recently completed rejuvenation of the VLA, providing observers with significantly increased continuum sensitivity and spectral survey speeds (by factors of 100 or more in select cases) from 1-50 GHz and in key bands below 1 GHz. Given the potential for new centimeter-wavelength sky surveys with this enhanced facility, the NRAO VLA Sky Survey (VLASS) has been initiated to explore the science and technical opportunities of a new large survey. A community-led Science Survey Group (SSG) will define the science program and key components of VLASS, and NRAO will support its technical design and implementation. The VLASS could start observing in early 2015, with the data available immediately with no proprietary period and science data products provided to the community in a timely manner. The new VLA can image young stars and massive black holes, measure the strength and topology of the cosmic magnetic field, follow the rapid evolution of energetic phenomena, and study the formation and evolution of stars, galaxies, AGN, and the Universe itself. We can follow the evolution of gas and galaxies and particles and fields to bridge the eras from cosmic dawn to the dawn of new worlds. To address these and other key science challenges requires the VLASS to address a number of key challenges in data management, computation, image processing, and analysis. The development and implementation of capable, efficient, and robust pipeline processing of data, and the production of a basic suite of science data products such as images and catalogs, are all high priorities for VLASS. We will describe the salient capabilities of the Jansky VLA, and highlight complementarity with multi-wavelength multi-messenger sky surveys with other facilities, ultimately leading into the era of the LSST. Exemplary VLA science and commissioning observations will illustrate these features. We will also summarize the outcome of the public NRAO VLASS Science Planning

  2. Rheumatoid arthritis, Proteus, anti-CCP antibodies and Karl Popper.

    Science.gov (United States)

    Ebringer, Alan; Rashid, Taha; Wilson, Clyde

    2010-02-01

    Rheumatoid arthritis (RA) is a crippling joint disease affecting over 20 million people worldwide. The cause of RA is most probably linked to the triad of microbial trigger, genetic association and autoimmunity and can be explained using the philosophical method of Karl Popper or Popperian sequences. Ten "Popper sequences" have been identified which point to the urinary microbe Proteus mirabilis as the cause of RA: Popper sequence 1 establishes that HLA-DR4 lymphocytes injected into a rabbit evoke specific antibodies against Proteus bacteria. Popper sequence 2 establishes that antibodies to Proteus bacteria are present in RA patients from 14 different countries. Popper sequence 3 establishes that antibodies to Proteus bacteria in RA patients are disease specific since no such antibodies are found in other conditions. Popper sequence 4 establishes that when RA patients have high titres of antibodies to Proteus such bacteria are found in urinary cultures. Popper sequence 5 establishes that only Proteus bacteria and no other microbes evoke significantly elevated antibodies in RA patients. Popper sequence 6 establishes that the "shared epitope" EQR(K)RAA shows "molecular mimicry" with the sequence ESRRAL found in Proteus haemolysin. Popper sequence 7 establishes that Proteus urease contains a sequence IRRET which has "molecular mimicry" with LRREI found in collagen XI of hyaline cartilage. Popper sequence 8 establishes that sera obtained from RA patients have cytopathic properties against sheep red cells coated with the cross-reacting EQR(K)RAA and LRREI self-antigen peptides. Popper sequence 9 establishes that Proteus sequences in haemolysin and urease as well as the self antigens, HLA-DR1/4 and collagen XI, each contain an arginine doublet, thereby providing a substrate for peptidyl arginine deiminase (PAD) to give rise to citrulline, which is the main antigenic component of CCP, antibodies to which are found in early cases of RA. Popper sequence 10 establishes that

  3. [The Hygienist Karl Roelcke, M.D. (1907-1982). Annotations to the family biography].

    Science.gov (United States)

    Mildenberger, Florian G

    2016-01-01

    Volker Roelcke, the well-known historian of medicine, wrote a biographical sketch on his father's role in National Socialism. Karl Roelcke (1907-1982) was an important hygienist at the University of Heidelberg and assistant to Ernst Rodenwaldt (1878-1965). Attempts to discuss the Nazi issue with his father directly ended unsuccessfully in the 1970s. In his essay of 2014, Volker Roelcke portrayed his father as quite sophisticated, but did not mention all aspects of his work. The present essay therefore offers new insights into the person of Karl Roelcke which are not constrained by family interests.

  4. Karl Julius Lohnert - an unknown astronomer, experimental psychologist and teacher (German Title: Karl Julius Lohnert - ein unbekannter Astronom, experimenteller Psychologe und Lehrer)

    Science.gov (United States)

    Schmadel, Lutz D.; Guski-Leinwand, Susanne

    2011-08-01

    Karl Julius Lohnert (1885-1944) with his double biography as astronomer and psychologist is hardly known in both fields. As a student of astronomy in Heidelberg, Lohnert discovered a couple of minor planets and he dedicated one to his PhD supervisor, the famous Leipzig professor for philosophy, Wilhelm Wundt. This connection is discussed for the first time almost one century after the naming of (635) Vundtia. The paper elucidates some biographical stations of Lohnert.

  5. Analysis of the Purity of Cetrimide by Titrations

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov; Rasmussen, Claus/Dallerup; Nielsen, Hans/Boye

    2006-01-01

    The purity of cetrimide, trimethyl tetradecyl ammonium bromide (TTAB), that is an important preservative of many cosmetic and pharmaceutical products, was determined by three independent methods of titration. Traditionally, cetrimide was analysed by an assay method of the European Pharmacopoeia (Ph....... Eur.), which showed consistently a low purity of cetrimide with large standard deviations associated, however. A systematic 3% bias of the Ph. Eur. assay method was identified by comparing the result with results of two alternative methods of titration that exhibited high precision and high accuracy....... Titration by perchloric acid showed a 99.69 ± 0.05 % purity of cetrimide and titration by silver nitrate showed a 99.85% ± 0.05 % purity while the traditional assay method predicted a purity of only 97.1 ± 0.4. It was found that the discrepancy could be identified as differences in selectivity during...

  6. A microcomputer-controlled system for titration analysis

    NARCIS (Netherlands)

    Boelema, Gerrit Jan

    1982-01-01

    This thesis deals with the results of the implementation of microprocessor technology in automatic titration equipment to obtain a versatile system for pharmaceutical, chemical analytical and optimization research purposes. ... Zie: Summary

  7. A Titration Technique for Demonstrating a Magma Replenishment Model.

    Science.gov (United States)

    Hodder, A. P. W.

    1983-01-01

    Conductiometric titrations can be used to simulate subduction-setting volcanism. Suggestions are made as to the use of this technique in teaching volcanic mechanisms and geochemical indications of tectonic settings. (JN)

  8. Titrated oral misoprostol solution- a new method of labour induction ...

    African Journals Online (AJOL)

    Titrated oral misoprostol solution- a new method of labour induction. ... a cheap, stable, orally active prostaglandin analogue, is effective for labour induction ... misoprostol doses commencing with 20 μg, increased after three doses to 40 μg.

  9. Complexometric Titration of Zinc: An Analytical Chemistry Laboratory Experiment

    Science.gov (United States)

    Novick, S. G.

    1997-12-01

    Complexometric titrations with EDTA have traditionally been performed in undergraduate analytical chemistry courses to determine the calcium or magnesium content of water. These titrations are performed at a basic pH, where the formation constants of Ca-EDTA and Mg-EDTA complexes are high. These types of problems are well-treated in the analytical chemistry textbooks. In contrast, treatment of metal ions whose EDTA complexes occur significantly at low pH (e.g., Zn2+, Fe3+, Cu2+, Ni2+, Pb2+, Al3+) is sparse. An incorrect conclusion can be reached by the student that practical EDTA titrations are only performed at high pH. In addition, widening the window of possible metal ions for complexometric titration affords the possibility of analyzing real world products, such as the cold lozenges discussed in the article.

  10. Microscope Titration and Extraction of DNA from Liver.

    Science.gov (United States)

    Mayo, Lois T.; And Others

    1993-01-01

    Describes a simple and inexpensive, one-period activity to extract DNA to make the study of DNA less abstract. A microscope titration is used to determine when cells are ready for DNA extraction. (PR)

  11. Microscope Titration and Extraction of DNA from Liver.

    Science.gov (United States)

    Mayo, Lois T.; And Others

    1993-01-01

    Describes a simple and inexpensive, one-period activity to extract DNA to make the study of DNA less abstract. A microscope titration is used to determine when cells are ready for DNA extraction. (PR)

  12. Depression may reduce adherence during CPAP titration trial

    National Research Council Canada - National Science Library

    Law, Mandy; Naughton, Matthew; Ho, Sally; Roebuck, Teanau; Dabscheck, Eli

    2014-01-01

    Depression is a risk factor for medication non-compliance. We aimed to identify if depression is associated with poorer adherence during home-based autotitrating continuous positive airway pressure (autoPAP) titration...

  13. Titration microcalorimetry of adsorption processes in aqueous systems

    NARCIS (Netherlands)

    Blandamer, Michael J.; Briggs, Barbara; Cullis, Paul M.; Irlam, Keith D.; Engberts, Jan B.F.N.; Kevelam, Jan

    1998-01-01

    Procedures are described for analysing enthalpograms characterising adsorption by macromolecules in solution recorded using a titration microcalorimeter. The experimental procedure involves injecting small aliquots of a solution containing adsorbate into a sample cell containing a solution of macrom

  14. A fully automatic system for acid-base coulometric titrations

    OpenAIRE

    1990-01-01

    An automatic system for acid-base titrations by electrogeneration of H+ and OH- ions, with potentiometric end-point detection, was developed. The system includes a PC-compatible computer for instrumental control, data acquisition and processing, which allows up to 13 samples to be analysed sequentially with no human intervention. The system performance was tested on the titration of standard solutions, which it carried out with low errors and RSD. It was subsequently applied to the analysis o...

  15. "Essential oils of Heracleum Persicum Desf.ex Fischer leaves "

    Directory of Open Access Journals (Sweden)

    Mojab F

    2002-07-01

    Full Text Available The leaves of Heracleum persicum Desf ex Fischer (Syn. H glabrascens Boiss. & Hohen, H. prbescens Rech. (Fam Apiaceae were collected in July - Auguest 1993 from kandavan area in north of Tehran. The oil was extracted by hydrodistillation (0.13% from leaves and was analyzed by GC, GC/CS and 1H-NMR. The major component was trans - anethole (82.8% Other components were β - pinene, p-cymene and terpinolene (monoterpenes , α- caryophylene, α- bergamotene, α- farnesene, zingiberene, spathulenol (sesqiterpenes. Cis - anethole, stragole, 2,5-dimethyl styrene (aromatic compounds, and β- springene ( an aliphatic and hydrocarbonic diterpene . It is concluded that this oil is a source of trans - anethole .

  16. TECHNOLOGY DEVELOPMENT FOR IRON FISCHER-TROPSCH CATALYSTS

    Energy Technology Data Exchange (ETDEWEB)

    Davis, B.H.

    1998-07-22

    The goal of the proposed work described in this Final Report was the development of iron-based Fischer-Tropsch catalysts that combined high activity, selectivity and life with physical robustness for slurry phase reactors that will produce either low-alpha or high-alpha products. The work described here has optimized the catalyst composition and pretreatment operation for a low-alpha catalyst. In parallel, work has been conducted to design a high-alpha iron catalyst that is suitable for slurry phase synthesis. Studies have been conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors have been studied at the laboratory scale. Catalyst performance has been determined for catalysts synthesized in this program for activity, selectivity and aging characteristics.

  17. Kinetic modelling of the Fischer-Tropsch synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Gambaro, C.; Pollesel, P.; Zennaro, R. [Eni S.p.A., San Donato Milanese (Italy); Lietti, L.; Tronconi, E. [Politecnico di Milano (Italy)

    2006-07-01

    In this work the development of a CO conversion kinetic model of the Fischer-Tropsch process will be presented. Kinetic data were produced testing a Co-based catalyst on two lab units, equipped with a slurry autoclave and a fixed bed reactor respectively. Accordingly, information on the catalytic performances of the same catalyst in two reactor configurations were also obtained. The experimental results were then analyzed with different kinetic models, available in the literature: two mechanistic models, derived by Sarup-Wojciechowski and Yates-Satterfield, and a simple power law rate expression were compared. The parameters of the different rate expressions were estimated by non-linear regression of the kinetic data collected on the two lab units. (orig.)

  18. Codependency and Validating Spann-Fischer in The Women of Mashhad

    Directory of Open Access Journals (Sweden)

    S Mhammad hasan Ashraf

    2010-11-01

    Full Text Available Objective: The aim of this study is validating Spann-Fischer (codependency test and investigating the "codependency" based on characteristics of the substance abuser wives. Methods: Spann-Fischer test normalize using a sample of 507 women. A sample contain of 204 women with addicted husbands who had referred to 33 qutting centers in Mashhad were analyzed and they also were used to validate the test. Results: The results confirm the validity and reliability of Spann-Fischer test, significant. Conclusion: The results emphasize the role of codependency as a factor against addiction treatment.

  19. The Potassium-Argon Laser Experiment (KarLE): In Situ Geochronology for Mars and Beyond

    Science.gov (United States)

    Cohen, Barbara A.

    2014-01-01

    The search for life in the solar system depends upon discovering the right moments in planetary evolution: when habitable environments existed, when they declined, and when geologic processes operated to preserve traces of life after death. However, an incomplete knowledge of absolute Martian geochronology limits our ability to understand the timing of Martian evolutionary milestones, major climate changes, and stratigraphic epochs [1, 2]. Absolute dating relates these habitability markers to planetarywide geologic, atmospheric, and climate history places, and ties their occurrence to the history of the solar system, especially the Earth-Moon system and the timescale of evolution of life on Earth. KArLE is being developed to anchor the relative timeline of geological events to an absolute chronology that puts Mars into a wider solar system context. KArLE makes its measurements on rock samples that can be obtained by landers or rovers and inserted into a small, mechanically simple chamber. KArLE interrogates the samples using laser-induced breakdown spectrocopy (LIBS), mass spectrometry, and optical imaging. The KArLE experiment is flexible enough to accommodate any partner providing these instrument components, a creative approach that extends the ability of mission payloads to accomplish an additional highly-desirable science measurement for low cost and risk and minimal extra hardware.

  20. Tänapäeva tantsuteatri mitu palet / Heili Einasto, Karl Toepfer

    Index Scriptorium Estoniae

    Einasto, Heili

    2015-01-01

    Vestlus San Jose ülikooli professori Karl Toepferiga nüüdisaegsest Eesti tantsuteatrist - I. Tuksami "Vassilissa", E. Tubina ja M Kesleri "Kratt", T. Olleski jt. "HTK", G. Reynoldsi ja S. Stubbsi "Gatsby", N. Rota ja G. Madia "La Dolce Vita", A. Toikka "Faust"

  1. Recalling Karl Jaspers' Classic: The Idea of the University. IHE Perspectives.

    Science.gov (United States)

    Fincher, Cameron

    This essay revisits Karl Jaspers' classic, "The Idea of the University." Jaspers was reinstated as president of Heidelberg University in 1945, and he presided over its rebuilding. His book, "The Idea of the University," written in 1946, was published in English 13 years later. It interprets an ideal of the university and emphasizes the purposes…

  2. Vendade Karl ja Artur Säre elukäigu salaniidistik / Valdur Ohmann

    Index Scriptorium Estoniae

    Ohmann, Valdur

    2003-01-01

    EKP I sekretäri Karl Säre ja tema vanema venna Artur Säre (Männi) elu ja tegevuse ülevaade. Artur Säre oli NSVL poliitilise esinduse teenistuses Hiina RV, NSVL Välisasjade Rahvakomissariaadi ja ENSV Ministrite Nõukogu juures

  3. Problematizing the "Taken for Granted" in Educational Issues: Karl Marx, Antonio Gramsci, and Michel Foucault.

    Science.gov (United States)

    Qi, Jie

    This paper explores how educators would raise different questions about educational issues by using Karl Marx's framework, Antonio Gramsci's conception, and Michel Foucault's notions, respectively. First, the paper compares the historical perspectives of Marx and Foucault. Marx concludes that history is a progressive linear production and that…

  4. USA presidendi üks peamisi nõunikke Karl Rove lahkub ametist / Kaivo Kopli

    Index Scriptorium Estoniae

    Kopli, Kaivo

    2007-01-01

    1993. aastast praeguse USA presidendi George B. Bushiga koos töötanud Karl Rove lahkub ametist perekonna huvides. K. Rove on uurimise all olnud seoses CIA agendi Valerie Plame'i paljastamisega, Senati komitee kuulas teda üle kaheksa föderaalprokuröri vallandamise uurimise raames

  5. El huracán Karl: concepciones sobre su origen en una comunidad de Veracruz

    National Research Council Canada - National Science Library

    Arturo Marinero Heredia; María José García Oramas

    2015-01-01

    ... por el huracán Karl en 2010, en el municipio de La Antigua, Veracruz. Los datos se obtuvieron de entrevistas a informantes claves y grupos focales, además de la revisión de notas periodísticas...

  6. Karl Ristikivi rändav Arkaadia / Janika Kronberg, Brita Melts

    Index Scriptorium Estoniae

    Kronberg, Janika, 1963-

    2012-01-01

    Artikkel jälgib Arkaadia-motiivi arengut Karl Ristikivi loomingus, toetudes nii autori poolt läbikäidud maastikele kui ka kunstikriitiku ja teoreetiku Simon Schama töödele. Käsitletakse ka Arkaadia motiivi Euroopa kultuuriloos

  7. Lidar - nesbõvshajasja estonskaja "nokia" / Karl Rebane ; interv. Julia Rodina

    Index Scriptorium Estoniae

    Rebane, Karl, 1926-2007

    2006-01-01

    Eesti NSV teadlaste poolt välja töötatud laserseade lidar, seadme ehitamisest, töötamise põhimõttest ja kasutusvaldkonnast. Akadeemik Karl Rebase sõnul ei oleks sellise ulatusega Läänemere saastamist juhtunud, kui Eestil oleks normaalne ökoloogilise kontrolli süsteem. Poliitikute suhtumisest kodumaise teaduse arengusse

  8. The Psychology of Thinking, Animal Psychology, and the Young Karl Popper

    NARCIS (Netherlands)

    ter Hark, M.R.M.

    2004-01-01

    In the 1920s, Karl Popper wrote two large manuscripts on psychology that he never published. in his autobiography, Unended Quest, he attempts to reduce the importance of his work in psychology as much as possible, and in his philosophical work he is an antipsychologist. However, in this article, it

  9. The Rejectability of Karl Popper: Why Popper's Ideas Have Had So Little Influence on Social Practice.

    Science.gov (United States)

    Burgess, Tyrrell; Swann, Joanna

    2003-01-01

    Addresses the question of why Karl Popper's work has been disregarded or rejected for educational improvement and suggests a series of impediments to an acceptance of Popper's ideas. Outlines a set of principle which if adopted as a basis for practice could lead to significant improvement. (EV)

  10. Ideal i realnost : Karl von Gershelman - poet-hudozhnik / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2005-01-01

    Eesti päritolu kunstniku Elisabeth Rosendorff-Hoerschelmanni (1898-1984) ja Eestiga seotud kunstniku ja kirjaniku Karl von Hoerschelmanni (1899-1951) elust ja loomingust. 2004. a. augustis-oktoobris oli kunstnike tööde näitus Adamson-Ericu muuseumis

  11. Ideal i realnost : Karl von Gershelman - poet-hudozhnik / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2005-01-01

    Eesti päritolu kunstniku Elisabeth Rosendorff-Hoerschelmanni (1898-1984) ja Eestiga seotud kunstniku ja kirjaniku Karl von Hoerschelmanni (1899-1951) elust ja loomingust. 2004. a. augustis-oktoobris oli kunstnike tööde näitus Adamson-Ericu muuseumis

  12. Karl Marx in One Lesson (1818-1883). Series on Public Issues No. 6.

    Science.gov (United States)

    Pejovich, Steve

    This booklet, one of a series intended to apply economic principles to major social and political issues of the day, starts from the premise that Marxism is a threat to our way of life and offers a critique of fundamental components of the social movement Marx created. The first of six subsections focuses on sources of influence on Karl Marx…

  13. Lidar - nesbõvshajasja estonskaja "nokia" / Karl Rebane ; interv. Julia Rodina

    Index Scriptorium Estoniae

    Rebane, Karl, 1926-2007

    2006-01-01

    Eesti NSV teadlaste poolt välja töötatud laserseade lidar, seadme ehitamisest, töötamise põhimõttest ja kasutusvaldkonnast. Akadeemik Karl Rebase sõnul ei oleks sellise ulatusega Läänemere saastamist juhtunud, kui Eestil oleks normaalne ökoloogilise kontrolli süsteem. Poliitikute suhtumisest kodumaise teaduse arengusse

  14. 17. oktoober 1905 - 1. märts 1917 / Karl Ast Rumor

    Index Scriptorium Estoniae

    Ast Rumor, Karl

    2007-01-01

    Üheteistkümneaastasest perioodist Karl Asti tagasivaatava isikliku pilgu läbi. Autor vabanes Riia vanglast oktoobrimanifesti põhjal. Ees ootasid uued vangistused. K. Asti isiklik mälestus Aleksandr Kerenskist. Varem ilmunud : "Pealinna Teataja" 9. märts 1917, nr. 3

  15. Developement of the Potassium-Argon Laser Experiment (KArLE) for In Situ Geochronology

    Science.gov (United States)

    Cohen, Barbara A.

    2012-01-01

    Absolute dating of planetary samples is an essential tool to establish the chronology of geological events, including crystallization history, magmatic evolution, and alteration. Thus far, radiometric geochronology of planetary samples has only been accomplishable in terrestrial laboratories on samples from dedicated sample return missions and meteorites. In situ instruments to measure rock ages have been proposed, but none have yet reached TRL 6, because isotopic measurements with sufficient resolution are challenging. We have begun work under the NASA Planetary Instrument Definition and Development Program (PIDDP) to develop the Potassium (K) - Argon Laser Experiment (KArLE), a novel combination of several flight-proven components that will enable accurate KAr isochron dating of planetary rocks. KArLE will ablate a rock sample, measure the K in the plasma state using laser-induced breakdown spectroscopy (LIBS), measure the liberated Ar using quadrupole mass spectrometry (QMS), and relate the two by measuring the volume of the abated pit using a optical methods such as a vertical scanning interferometer (VSI). Our preliminary work indicates that the KArLE instrument will be capable of determining the age of several kinds of planetary samples to 100 Myr, sufficient to address a wide range of geochronology problems in planetary science. Additional benefits derive from the fact that each KArLE component achieves analyses common to most planetary surface missions.

  16. Tänapäeva tantsuteatri mitu palet / Heili Einasto, Karl Toepfer

    Index Scriptorium Estoniae

    Einasto, Heili

    2015-01-01

    Vestlus San Jose ülikooli professori Karl Toepferiga nüüdisaegsest Eesti tantsuteatrist - I. Tuksami "Vassilissa", E. Tubina ja M Kesleri "Kratt", T. Olleski jt. "HTK", G. Reynoldsi ja S. Stubbsi "Gatsby", N. Rota ja G. Madia "La Dolce Vita", A. Toikka "Faust"

  17. 17. oktoober 1905 - 1. märts 1917 / Karl Ast Rumor

    Index Scriptorium Estoniae

    Ast Rumor, Karl

    2007-01-01

    Üheteistkümneaastasest perioodist Karl Asti tagasivaatava isikliku pilgu läbi. Autor vabanes Riia vanglast oktoobrimanifesti põhjal. Ees ootasid uued vangistused. K. Asti isiklik mälestus Aleksandr Kerenskist. Varem ilmunud : "Pealinna Teataja" 9. märts 1917, nr. 3

  18. Mineviku kummitused : Stasi arhiivist leiti Karl-Heinz Kurrase aktid / Aino Siebert

    Index Scriptorium Estoniae

    Siebert, Aino

    2009-01-01

    On ilmsiks tulnud dokumendid, mis tõestavad, et Saksa DV Riikliku Julgeolekuministeeriumi agent Karl-Heinz Kurras tappis Lääne-Berliinis Iraani monarhi visiidi ajal 1967. aasta 2. juunil toimunud meeleavalduste käigus üliõpilase Benno Ohnesorgi

  19. Taani tahab meid ELi kutsuda / Mariann Fischer Boel ; interv. Marianne Mikko

    Index Scriptorium Estoniae

    Fischer Boel, Mariann

    2002-01-01

    Taani põllumajandusminister Mariann Fischer Boel vastab küsimustele Eesti soovitud piimakvoodi, EL-i tulevaste liikmesriikide otsetoetuste, Taanis maa ostmise, Eesti üliliberaalse majanduse ja sotsiaalse heaolu ühendamise võimaluse kohta

  20. Different Characters of Spleen OX-62 Positive Dendritic Cells between Fischer and Lewis Rats

    Institute of Scientific and Technical Information of China (English)

    Linsong Yang; Yayi Hou

    2006-01-01

    The phenotype, DNA-binding activities of NF-κB, cytokine production, endocytosis and stimulatory capacity of spleen OX-62-positive dendritc cells (SDCs) from Fischer rats were compared with those from Lewis rats. Results showed that the expressions of CD11b, MHC-Ⅱ, CD8, CD45RA, CD54 and CD86 on SDCs were significantly higher in Fischer than those in Lewis rats. The levels of IL-2, IL-4, IL-10 and IFN-γ in SDCs from Fischer rats were distinctly higher than those from Lewis. Both stimulatory capacity and DNA-binding activities of NF-κB in SDCs were all lower in Fischer than those in Lewis rats. These differences may partly contribute to rat strainspecificity in susceptibility to chronic inflammatory stimuli.

  1. Taani tahab meid ELi kutsuda / Mariann Fischer Boel ; interv. Marianne Mikko

    Index Scriptorium Estoniae

    Fischer Boel, Mariann

    2002-01-01

    Taani põllumajandusminister Mariann Fischer Boel vastab küsimustele Eesti soovitud piimakvoodi, EL-i tulevaste liikmesriikide otsetoetuste, Taanis maa ostmise, Eesti üliliberaalse majanduse ja sotsiaalse heaolu ühendamise võimaluse kohta

  2. The Metabolism of CIS - and Trans - Decalin in Fischer 344 Rats.

    Science.gov (United States)

    1985-12-09

    convulsions. A human with prolonged exposure to decalin was found to have intense pruritus and vesicular eczema ; the presence of albumin and leukocytes in...urine also suggested kidney involvement. (3) In 1980, Gaworski et al. reported on the subchronic inhalation toxicity of decalin in * Beagle dogs , Fischer... dogs . Pathologic studies showed no gross or microscopic lesions in these dogs . The growth of male Fischer 344 rats was retarded by exposure to decalin

  3. Succeser og fiaskoer i Fischer Boels periode som landbrugskommisær

    DEFF Research Database (Denmark)

    Kærgård, Niels; Zobbe, Henrik

    2010-01-01

    Når Mariann Fischer Boel nu overlader posten som EU's landbrugskommisær til rumæneren Dacian Ciolos, slutter endnu en periode med dansk ledelse af dette vigtige EU-område......Når Mariann Fischer Boel nu overlader posten som EU's landbrugskommisær til rumæneren Dacian Ciolos, slutter endnu en periode med dansk ledelse af dette vigtige EU-område...

  4. Making pH calculations in the titration of strong protolytes

    OpenAIRE

    2013-01-01

    Titration graphs of protolytic systems are very useful among other things to find the equivalence point (ep), choose the most suitable indicator, calculate the titration error and decide whether a given titration is feasible or not under certain conditions. The main feature of a titration curve is the pH jump that occurs in the vicinity of the equivalence point. Titration graphs can be obtained experimentally using the potentiometric method with the pH electrode. They also can be obtained the...

  5. Potentiometric titration and equivalent weight of humic acid

    Science.gov (United States)

    Pommer, A.M.; Breger, I.A.

    1960-01-01

    The "acid nature" of humic acid has been controversial for many years. Some investigators claim that humic acid is a true weak acid, while others feel that its behaviour during potentiometric titration can be accounted for by colloidal adsorption of hydrogen ions. The acid character of humic acid has been reinvestigated using newly-derived relationships for the titration of weak acids with strong base. Re-interpreting the potentiometric titration data published by Thiele and Kettner in 1953, it was found that Merck humic acid behaves as a weak polyelectrolytic acid having an equivalent weight of 150, a pKa of 6.8 to 7.0, and a titration exponent of about 4.8. Interdretation of similar data pertaining to the titration of phenol-formaldehyde and pyrogallol-formaldehyde resins, considered to be analogs for humic acid by Thiele and Kettner, leads to the conclusion that it is not possible to differentiate between adsorption and acid-base reaction for these substances. ?? 1960.

  6. Synthesis gas solubility in Fischer-Tropsch slurry: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Chao, K.C.; Lin, H.M.

    1988-01-01

    The objective is to investigate the phase equilibrium behavior of synthesis gases and products in a Fischer-Tropsch slurry reactor. A semi-flow apparatus has been designed and constructed for this purpose. Measurements have been made for hydrogen, cabon monoxide, methane, ethane, ethylene, and carbon dioxide in a heavy n-paraffin at temperatures from 100 to 300)degree)C and pressures 10 to 50 atm. Three n-paraffin waxes: n-eicosane (n-C/sub 20/), n-octacosane )n-C/sub 28/), and n-hexatriacontane (n-C/sub 36/), were studied to model the industrial wax. Solubility of synthesis gas mixtures of H/sub 2/ and CO in n-C/sub 28/ was also determined at two temperatures (200 and 300)degree)C) for each of three gas compositions (40.01, 50.01, and 66.64 mol%) of hydrogen). Measurements were extended to investigate the gas solubility in two industrial Fischer-Tropsch waxes: Mobilwax and SASOL wax. Observed solubility increases in the order: H/sub 2/, CO, CH/sub 4/, CO/sub 2/, C/sub 2/H/sub 4/, C/sub 2/H/sub 6/, at a given temperature pressure, and in the same solvent. Solubility increases with increasing pressure for all the gases. Lighter gases H/sub 2/ and CO show increased solubility with increasing temperature, while the heavier gases CO/sub 2/, ethane, and ethylene show decreased solubility with increasing temperature. The solubility of methane, the intermediate gas, changes little with temperature, and shows a shallow minimum at about 200)degrees)C or somewhat above. Henry's constant and partial molal volume of the gas solute at infinite dilution are determinedfrom the gas solubility data. A correlation is developed from the experimental data in the form on an equation of state. A computer program has been prepared to implement the correlation. 19 refs., 66 figs., 39 tabs.

  7. Reduction and reoxidation of cobalt Fischer-Tropsch catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Hilmen, Anne-Mette

    1996-12-31

    The Fischer-Tropsch synthesis involves the hydrogenation of carbon monoxide to produce mainly hydrocarbons, water and carbon dioxide, but also alcohols, aldehydes and acids are formed. The distribution of these products is determined by the choice of catalyst and synthesis conditions. This thesis studies the reduction and reoxidation of 17%Co/Al{sub 2}O{sub 3} and 17%Co-1%Re/Al{sub 2}O{sub 3} by means of several characterization techniques. The effect of small amounts of Re on the reduction properties of Al{sub 2}O{sub 3}-supported Co catalysts has been studied by temperature-programmed reduction (TPR). An intimate mixture of CoAl{sub 2}O{sub 3} and Re/Al{sub 2}O{sub 3} catalysts showed a promoting effect of Re similar to that for co impregnated CoRe/Al{sub 2}O{sub 3}. A loose mixture of Co/Al{sub 2}O{sub 3} + Re/Al{sub 2}O{sub 3} did not show any effect of Re on the reduction of Co. But a promoting effect was observed if the mixture had been pre-treated with Ar saturated with water before the TPR. It is suggested that Re promotes the reduction of Co oxide by hydrogen spillover. It is shown that a high temperature TPK peak at 1200K assigned to Co aluminate is mainly caused by the diffusion of Co ions during the TPR and not during calcination. The Co particle size measured by x-ray diffraction on oxidized catalysts decreased compared to the particle size on the calcined catalysts, while the dispersion measured by volumetric chemisorption decreased somewhat after the oxidation-reduction treatment. The role of water in the deactivation of Co/Al{sub 2}O{sub 3} and CoRe/Al{sub 2}O{sub 3} Fischer-Tropsch catalysts has been extensively studied. There were significant differences in the reducibility of the phases formed for the two catalysts during exposure to H{sub 2}O/He. 113 refs., 76 figs., 18 tabs.

  8. Karl Marx, un periodista en la Era del Capital. Apuntes para una investigación

    Directory of Open Access Journals (Sweden)

    Espinoza Pino, Mario

    2014-06-01

    Full Text Available The aim of this article is to criticize the traditional representation of Karl Marx’s journalistic works, usually forgotten by a misleading canon that assumes his articles only as a minor work. One of the problems of this traditional conception is that it dissociates his theoretical and economic contributions from the historical development of the author’s thought (and also from its material roots. We will try to point the importance of Karl Marx’s mature journalism in two areas: in the construction of the central concepts of his critic against the capitalist mode of production (surplus value, a multilineal historical perspective, a global description of the world market, etc. and in the production of political cartographies to intervene in the class conflict. This article poses several hypothesis and tentative affirmations about Karl Marx’s journalism that may serve as a point of departure for a critical research.El objetivo de este artículo es criticar la representación tradicional del trabajo periodístico de Karl Marx, habitualmente olvidado por un canon engañoso que sólo asume sus artículos al precio de convertirlos en una obra menor. Uno de los problemas de esta concepción tradicional es que disocia sus contribuciones teóricas y económicas del desarrollo histórico del pensamiento del autor (y también de sus raíces materiales. Intentaremos señalar la importancia del periodismo maduro de Karl Marx en dos áreas: en la construcción de los conceptos centrales de su crítica contra el capitalismo (plusvalor, un enfoque histórico multilineal, una descripción global del mercado mundial, etc. y en la producción de cartografías políticas para intervenir en el conflicto de clases. Este artículo plantea varias hipótesis y afirmaciones tentativas sobre el periodismo de Karl Marx que pueden servir como punto de partida de una investigación crítica.

  9. Fischer-Tropsch diesel production over calcium-promoted Co/alumina catalyst: Effect of reaction conditions

    Energy Technology Data Exchange (ETDEWEB)

    A.R. de la Osa; A. De Lucas; A. Romero; J.L. Valverde; P. Sanchez [University of Castilla-La Mancha, Ciudad Real (Spain). Chemical Engineering Department

    2011-05-15

    The effects of reaction conditions on the Fischer-Tropsch activity and product distribution of an alkali-earth metal promoted cobalt based catalyst were studied. The influence of the promoter on the reducibility and cobalt particle size was studied by different techniques, including N{sub 2} adsorption, X-ray diffraction, temperature-programmed reduction, temperature-programmed desorption and acid-base titrations. Experiments were carried out on a bench-scale fixed bed reactor and catalysts were prepared by incipient wetness impregnation. It was observed that addition of a small amount of calcium oxide as a promoter (0.6 wt.%) improved the cobalt oxide reducibility and reduced the formation of cobalt-aluminate species. A positive correlation between basicity and particle size was observed. In terms of FTS results, CO conversion and C{sub 5}{sup +} selectivity were found to be enhanced by the addition of this promoter. It was important to note that the addition of calcium shifted the distribution to mainly C{sub 16}-C{sub 18} hydrocarbons fraction, which could be greatly considered for a diesel formulation. Furthermore, the variation of the reaction conditions seemed to influence product distribution in a lesser extent than unpromoted catalyst. Also, a displacement of hydrocarbon distribution to higher molecular weight with decreasing space velocity and temperature was observed. Moreover, the addition of calcium to the cobalt based catalyst was found to greatly maintain selectivity to C{sub 5}{sup +} for a wide range of H{sub 2}/CO molar ratios. 60 refs., 10 figs., 5 tabs.

  10. Roosna-Alliku mõisa häärber / Karl Kolopka, Nele Rohtla, Johann Schultz

    Index Scriptorium Estoniae

    Kolopka, Karl

    2004-01-01

    12 ill.; peahoone ehitati Johann Schultzi kavandite järgi, siseinterjööri ilmestava Louis XVI stiilis stukitöö tegi Karl Kolopka, häärber restaureeriti Nele Rohtla (OÜ Mõisaprojekt) suunamisel

  11. New applications of corrosion measurements by titration (CMT)

    DEFF Research Database (Denmark)

    Bech-Nielsen, Gregers

    1998-01-01

    CMT measurements and electrochemical (EC) measurements of corrosion rate are generally in agreement, when only electrochemical dissolution of metals in acid take place. However, dissolution of oxide layers and other acid-consuming reactions can cause CMT measurements to exceed EC measurements....... It is shown that when aluminium dissolves in alkali, CMT measurements can also be applied, but in this case requiring titration with alkali. Titration with alkali is also required in a special situation, where corrosion of nickel in an acid solution and subsequent formation of a nickel complex results...

  12. Fast coarse-grained model for RNA titration

    Science.gov (United States)

    Barroso da Silva, Fernando Luís; Derreumaux, Philippe; Pasquali, Samuela

    2017-01-01

    A new numerical scheme for RNA (ribonucleic acid) titration based on the Debye-Hückel framework for the salt description is proposed in an effort to reduce the computational costs for further applications to study protein-RNA systems. By means of different sets of Monte Carlo simulations, we demonstrated that this new scheme is able to correctly reproduce the experimental titration behavior and salt pKa shifts. In comparison with other theoretical approaches, similar or even better outcomes are achieved at much lower computational costs. The model was tested on the lead-dependent ribozyme, the branch-point helix, and the domain 5 from Azotobacter vinelandii Intron 5.

  13. Chemical imaging of Fischer-Tropsch catalysts under operating conditions

    Science.gov (United States)

    Price, Stephen W. T.; Martin, David J.; Parsons, Aaron D.; Sławiński, Wojciech A.; Vamvakeros, Antonios; Keylock, Stephen J.; Beale, Andrew M.; Mosselmans, J. Frederick W.

    2017-01-01

    Although we often understand empirically what constitutes an active catalyst, there is still much to be understood fundamentally about how catalytic performance is influenced by formulation. Catalysts are often designed to have a microstructure and nanostructure that can influence performance but that is rarely considered when correlating structure with function. Fischer-Tropsch synthesis (FTS) is a well-known and potentially sustainable technology for converting synthetic natural gas (“syngas”: CO + H2) into functional hydrocarbons, such as sulfur- and aromatic-free fuel and high-value wax products. FTS catalysts typically contain Co or Fe nanoparticles, which are often optimized in terms of size/composition for a particular catalytic performance. We use a novel, “multimodal” tomographic approach to studying active Co-based catalysts under operando conditions, revealing how a simple parameter, such as the order of addition of metal precursors and promoters, affects the spatial distribution of the elements as well as their physicochemical properties, that is, crystalline phase and crystallite size during catalyst activation and operation. We show in particular how the order of addition affects the crystallinity of the TiO2 anatase phase, which in turn leads to the formation of highly intergrown cubic close-packed/hexagonal close-packed Co nanoparticles that are very reactive, exhibiting high CO conversion. This work highlights the importance of operando microtomography to understand the evolution of chemical species and their spatial distribution before any concrete understanding of impact on catalytic performance can be realized. PMID:28345057

  14. ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

    Energy Technology Data Exchange (ETDEWEB)

    K. Jothimurugesan; James G. Goodwin, Jr.; Santosh K. Gangwal

    1999-10-01

    Fischer-Tropsch (FT) synthesis to convert syngas (CO + H{sub 2}) derived from natural gas or coal to liquid fuels and wax is a well-established technology. For low H{sub 2} to CO ratio syngas produced from CO{sub 2} reforming of natural gas or from gasification of coal, the use of Fe catalysts is attractive because of their high water gas shift activity in addition to their high FT activity. Fe catalysts are also attractive due to their low cost and low methane selectivity. Because of the highly exothermic nature of the FT reaction, there has been a recent move away from fixed-bed reactors toward the development of slurry bubble column reactors (SBCRs) that employ 30 to 90 {micro}m catalyst particles suspended in a waxy liquid for efficient heat removal. However, the use of FeFT catalysts in an SBCR has been problematic due to severe catalyst attrition resulting in fines that plug the filter employed to separate the catalyst from the waxy product. Fe catalysts can undergo attrition in SBCRs not only due to vigorous movement and collisions but also due to phase changes that occur during activation and reaction.

  15. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    Dragomir B. Bukur; Gilbert F. Froment; Lech Nowicki; Jiang Wang; Wen-Ping Ma

    2003-09-29

    This report covers the first year of this three-year research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict concentrations of all reactants and major product species (H{sup 2}O, CO{sub 2}, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the reporting period we have completed one STSR test with precipitated iron catalyst obtained from Ruhrchemie AG (Oberhausen-Holten, Germany). This catalyst was initially in commercial fixed bed reactors at Sasol in South Africa. The catalyst was tested at 13 different sets of process conditions, and had experienced a moderate deactivation during the first 500 h of testing (decrease in conversion from 56% to 50% at baseline process conditions). The second STSR test has been initiated and after 270 h on stream, the catalyst was tested at 6 different sets of process conditions.

  16. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    Dragomir B. Bukur

    2004-09-29

    This report covers the second year of this three-year research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict concentrations of all reactants and major product species (H{sub 2}O, CO{sub 2}, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the second year of the project we completed the STSR test SB-26203 (275-343 h on stream), which was initiated during the first year of the project, and another STSR test (SB-28603 lasting 341 h). Since the inception of the project we completed 3 STSR tests, and evaluated catalyst under 25 different sets of process conditions. A precipitated iron catalyst obtained from Ruhrchemie AG (Oberhausen-Holten, Germany) was used in all tests. This catalyst was used initially in commercial fixed bed reactors at Sasol in South Africa. Also, during the second year we performed a qualitative analysis of experimental data from all three STSR tests. Effects of process conditions (reaction temperature, pressure, feed composition and gas space velocity) on water-gas-shift (WGS) activity and hydrocarbon product distribution have been determined.

  17. TECHNOLOGY DEVELOPMENT FOR IRON AND COBALT FISCHER-TROPSCH CATALYSTS

    Energy Technology Data Exchange (ETDEWEB)

    Burtron H. Davis

    1999-04-30

    The impact of activation procedure on the phase composition of precipitated iron Fischer-Tropsch (FT) catalysts has been studied. Catalyst samples taken during activation and FT synthesis have been characterized by Moessbauer spectroscopy. Formation of iron carbide is necessary for high FT activity. Hydrogen activation of precipitated iron catalysts results in reduction to predominantly metallic iron and Fe{sub 3}O{sub 4}. Metallic iron is not stable under FT 3 4 conditions and is rapidly converted to {epsilon}{prime}-Fe{sub 2.2}C. Activation with carbon monoxide or syngas 2.2 with low hydrogen partial pressure reduces catalysts to {chi}-Fe{sub 5}C{sub 2} and a small amount of 5 2 superparamagnetic carbide. Exposure to FT conditions partially oxidizes iron carbide to Fe{sub 3}O{sub 4}; however, catalysts promoted with potassium or potassium and copper maintain a constant carbide content and activity after the initial oxidation. An unpromoted iron catalyst which was activated with carbon monoxide to produce 94% {chi}-Fe{sub 5}C{sub 2}, deactivated rapidly as the carbide was oxidized to Fe{sub 3}O{sub 4}. No difference in activity, stability or deactivation rate was found for {chi}-Fe{sub 5}C{sub 2} and {epsilon}{prime}-Fe{sub 2.2}C.

  18. Age Dependent Variability in Gene Expression in Fischer 344 ...

    Science.gov (United States)

    Recent evidence suggests older adults may be a sensitive population with regard to environmental exposure to toxic compounds. One source of this sensitivity could be an enhanced variability in response. Studies on phenotypic differences have suggested that variation in response does increase with age. However, few reports address the question of variation in gene expression as an underlying cause for increased variability of phenotypic response in the aged. In this study, we utilized global analysis to compare variation in constitutive gene expression in the retinae of young (4 mos), middle-aged (11 mos) and aged (23 mos) Fischer 344 rats. Three hundred and forty transcripts were identified in which variance in expression increased from 4 to 23 mos of age, while only twelve transcripts were found for which it decreased. Functional roles for identified genes were clustered in basic biological categories including cell communication, function, metabolism and response to stimuli. Our data suggest that population stochastically-induced variability should be considered in assessing sensitivity due to old age. Recent evidence suggests older adults may be a sensitive population with regard to environmental exposure to toxic compounds. One source of this sensitivity could be an enhanced variability in response. Studies on phenotypic differences have suggested that variation in response does increase with age. However, few reports address the question of variation in

  19. Technology development for iron Fischer-Tropsch catalysts

    Energy Technology Data Exchange (ETDEWEB)

    O`Brien, R.J.; Raje, A.; Keogh, R.A. [and others

    1995-12-31

    The objective of this research project is to develop the technology for the production of physically robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry phase synthesis reactor development. The catalysts that are developed shall be suitable for testing in the Advanced Fuels Development Facility at LaPorte, Texas, to produce either low-or high-alpha product distributions. Previous work by the offeror has produced a catalyst formulation that is 1.5 times as active as the {open_quotes}standard-catalyst{close_quotes} developed by German workers for slurry phase synthesis. In parallel, work will be conducted to design a high-alpha iron catalyst this is suitable for slurry phase synthesis. Studies will be conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors will be studied at the laboratory scale. Catalyst performance will be determined for catalysts synthesized in this program for activity, selectivity and aging characteristics.

  20. The Fischer 344 rat as a model of presbycusis.

    Science.gov (United States)

    Syka, Josef

    2010-06-01

    Due to the rising number of the aged human population all over the world, presbycusis is a phenomenon that deserves the increasing attention of the medical community as regards to prevention and treatment. This requires finding appropriate animal models for human presbycusis that will be useful in future experiments. Among the available rat strains, the Fischer 344 (F344) strain promises to serve as a model producing prompt and profound presbycusis. Hearing thresholds begin to increase in this strain during the first year of life; toward the end of the second year, the thresholds are very high. The threshold shifts progress independently in both ears. The rapid deterioration of distortion product otoacoustic emissions, with the majority of outer hair cells (OHC) being present and morphologically intact, is apparently produced by the disruption of prestin. The age-related changes within inner ear function are accompanied by deterioration of acoustical signal processing within central auditory system, mainly due to impaired GABA inhibition. The loss of GABA inhibition in old animals is expressed primarily in the inferior colliculus but is also present in the cochlear nuclei and the auditory cortex. Sound-evoked behavioral reactions are also impaired in old F344 rats. Taken together, the described characteristics of the aging F344 rat auditory system supports the idea that this strain may serve as a suitable model for studying the mechanisms of presbycusis, its prevention and treatment.

  1. Nanostructured Thin Films Obtained from Fischer Aminocarbene Complexes

    Directory of Open Access Journals (Sweden)

    Rosa E. Lazo-Jiménez

    2016-03-01

    Full Text Available The synthesis of four amphiphilic organometallic complexes with the general formula RC = M(CO5NH(CH215CH3, where R is a ferrocenyl 2(a-b or a phenyl 4(a-b group as a donor moiety and a Fischer carbene of chromium (0 or tungsten (0 as an acceptor group, are reported. These four push-pull systems formed Langmuir (L monolayers at the air-water interface, which were characterized by isotherms of surface pressure versus molecular area and compression/expansion cycles (hysteresis curves; Brewster angle microscopic images were also obtained. By using the Langmuir–Blodgett (LB method, molecular monolayers were transferred onto glass substrates forming Z-type multilayers. LB films were characterized through ultraviolet-visible spectroscopy, atomic force microscopy and X-ray diffraction techniques. Results indicated that films obtained from 2b complex [(Ferrocenyl(hexadecylaminemethylidene] pentacarbonyl tungsten (0 are the most stable and homogeneous; due to their properties, these materials may be incorporated into organic electronic devices.

  2. "Titration simulator"--Good assistant for titration analysis%滴定分析教学的好帮手"Titration simulator"

    Institute of Scientific and Technical Information of China (English)

    屠婕红

    2005-01-01

    @@ Titration simulator(滴定模拟器)软件是专门为滴定分析而设计的教学软件,它短小精悍,简洁实用,可以从Internet网上免费下载,网址为:http://www.chemonline.net/Truechemsoft/downsoft.asp?softID=1565该软件所占容量仅为72KB,是学生训练及化学教师的好助手.笔者在教学中尝试运用该软件辅助教学,效果良好,现将Titration simulator软件的主要功能、应用简要介绍如下:

  3. Der Briefwechsel zwischen Alexander von Humboldt und Karl Ernst von Baer

    Directory of Open Access Journals (Sweden)

    Thomas Schmuck

    2012-10-01

    Full Text Available Zusammenfassung Der kurze, nicht vollständig erhaltene Briefwechsel zwischen Alexander von Humboldt und Karl Ernst von Baer behandelt sehr verschiedene Themen: Politik, Kriegsgefahr, den Wissenschaftsbetrieb, Auszeichnungen und Tagungen, Embryologie und Cholera. Gemeinsam mit Briefen und Reden ergibt sich dabei ein differenziertes Bild der Beurteilung der beiden Wissenschaftler durch den jeweils anderen. Während Baer sich als Bewunderer Humboldts erweist, erscheint umgekehrt Humboldts Einschätzung Baers als ambivalent. Abstract The short, not completely preserved correspondence between Alexander von Humboldt and Karl Ernst von Baer deals with a wide range of subjects: politics and the danger of war, academic activities, scientific awards and conferences, aspects of embryology and the cholera. Letters to third persons and speeches, together with the correspondence between Humboldt and Baer show a differentiated pattern of mutual appraisal: While Baer always remained an admirer of the elder naturalist, Humboldt’s estimation was characterized by ambivalence.

  4. The Potassium-Argon Laser Experiment (KArLE): In Situ Geochronology for Planetary Robotic Missions

    Science.gov (United States)

    Cohen, Barbara

    2016-01-01

    The Potassium (K) - Argon (Ar) Laser Experiment (KArLE) will make in situ noble-gas geochronology measurements aboard planetary robotic landers and roverss. Laser-Induced Breakdown Spectroscopy (LIBS) is used to measure the K abun-dance in a sample and to release its noble gases; the evolved Ar is measured by mass spectrometry (MS); and rela-tive K content is related to absolute Ar abundance by sample mass, determined by optical measurement of the ablated volume. KArLE measures a whole-rock K-Ar age to 10% or better for rocks 2 Ga or older, sufficient to resolve the absolute age of many planetary samples. The LIBS-MS approach is attractive because the analytical components have been flight proven, do not require further technical development, and provide complementary measurements as well as in situ geochronology.

  5. Karl Menningu (ja iseenese) päästmiseks / Ants Hein

    Index Scriptorium Estoniae

    Hein, Ants, 1952-

    2008-01-01

    Vastuseks Karin Hallas-Murula arvustusele "Maja, mis on sümbol" (Sirp, 2007, 5. X, lk. 13) ja Mait Väljase arvustusele "Iseolemise algus arhitektuuris" (Maja, 2008, nr. 1, lk. 86-87) oma 2007. a. ilmunud raamatust "Maja kui sümbol : Eesti Üliõpilaste Seltsi hoone Tartus" kohta. Georg Hellati ja Karl Menningu osalusest EÜS-i hoone sünniloos. Frank Lloyd Wrightist kui võimalikust eeskujuandjast

  6. Karl Menningu (ja iseenese) päästmiseks / Ants Hein

    Index Scriptorium Estoniae

    Hein, Ants, 1952-

    2008-01-01

    Vastuseks Karin Hallas-Murula arvustusele "Maja, mis on sümbol" (Sirp, 2007, 5. X, lk. 13) ja Mait Väljase arvustusele "Iseolemise algus arhitektuuris" (Maja, 2008, nr. 1, lk. 86-87) oma 2007. a. ilmunud raamatust "Maja kui sümbol : Eesti Üliõpilaste Seltsi hoone Tartus" kohta. Georg Hellati ja Karl Menningu osalusest EÜS-i hoone sünniloos. Frank Lloyd Wrightist kui võimalikust eeskujuandjast

  7. Karl Popper: a propósito de La sociedad abierta y sus enemigos

    OpenAIRE

    Tobón Sanín , Gilberto

    2016-01-01

    Este texto pretende llevar a cabo una crítica al racionalismo extremo de Karl Popper, a veces rayano en el subjetivismo, pues racionalismo e irracionalismo en las sociedades son momentos de una totalidad más amplia de la realidad histórica, como quiera que la sociedad se mueve es por los conflictos y las contradicciones, y no por los consensos efímeros de las partes en conflicto. 

  8. Tim, Jan Lucas ja Karl Robert - vennad üheks kuuks / Maris Laurits

    Index Scriptorium Estoniae

    Laurits, Maris

    2009-01-01

    Rakvere Teatri suvelavastuse "Vennad Lõvisüdamed" kaks Karli osatäitjat Jan Lucas Videvik ja Tim Leesnurm ning Joonatani osatäitja Karl Robert Saaremäe tegid Loksal Kaldmaa talus ratsasõiduproove. Üllar Saaremäe lavastuse "Vennad Lõvisüdamed" (Astrid Lindgreni samanimelise jutustuse järgi) esietendus on 11. juunil Rakvere teatri taga aias

  9. Den første Karl Gustav-krig 1657-58

    DEFF Research Database (Denmark)

    Olden-Jørgensen, Sebastian

    2008-01-01

    Artiklen diskuterer den første Karl Gustav-krig i forskellige persketiver og konkluderer, at krigen ikke bør opfattes som et dårligt forberedt og uigennemtænkt forsøg på dansk revanche inden for rammerne af en nordisk rivalisering, men snarere som  en velovervejet satsning og et led i den dansk-s...

  10. Karl E. Weickの組織化概念の基礎的検討

    OpenAIRE

    星井, 進介; Hoshii, Shinsuke

    2011-01-01

    In The Social Psychology of Organizing, 2nd edition, Karl E. Weiek described an organizing theory based on flows, changes, connections, interdependence, and social interaction. This paper examined the definition and process of organizing proposed by Weick. The process of organizing and how organization emerges in Weick's book are discussed. Organizing was defined by Weick as a consensually validated grammar for reducing equivoeality by means of sensible interlocked behaviors. Weick showed tha...

  11. Tim, Jan Lucas ja Karl Robert - vennad üheks kuuks / Maris Laurits

    Index Scriptorium Estoniae

    Laurits, Maris

    2009-01-01

    Rakvere Teatri suvelavastuse "Vennad Lõvisüdamed" kaks Karli osatäitjat Jan Lucas Videvik ja Tim Leesnurm ning Joonatani osatäitja Karl Robert Saaremäe tegid Loksal Kaldmaa talus ratsasõiduproove. Üllar Saaremäe lavastuse "Vennad Lõvisüdamed" (Astrid Lindgreni samanimelise jutustuse järgi) esietendus on 11. juunil Rakvere teatri taga aias

  12. Some epistemology ́s elements of Social Science by Karl PopperAlguns elementos da Epistemolgia da Ciências Sociais de Karl Popper

    Directory of Open Access Journals (Sweden)

    Julio Cesar Rodrigues Pereira

    2010-12-01

    Full Text Available This article discusses the main elements of the epistemology of human sciences of Karl Popper. It was organized as follows. First, we positioned ourselves in the Popper-Adorno controversy. Then weestablished the parameters of discussion, particularly in regards to the idea of “scientific explanation”. Some elements of Popper’s Theory of Knowledge are then analyzed. The final part discusses thescientific parameters of Social Sciences.Este artigo discute os principais elementos da epistemologia das ciências humanas de Karl Popper. Foi organizado como segue. Em primeiro lugar, nos posionamos sobre a  polêmica Popper-Adorno. Então, nós estabelecemos os parâmetros de discussão, nomeadamente no que respeita a idéia de "explicação científica". A seguir são analisados alguns elementos da Teoria do Conhecimento de Popper. A parte final discute os parâmetros científicos de Ciências Sociais

  13. Ventilated external walls, constructed based on the building physics principles developed by Karl Gertis.; Hinterlueftete Aussenwaende, konstruiert aufgrund der von Karl Gertis erarbeiteten bauphysikalischen Grundlagen

    Energy Technology Data Exchange (ETDEWEB)

    Cziesielski, Erich [CRP Bauingenieure GmbH, Berlin (Germany)

    2008-12-15

    In his postdoctoral thesis Karl Gertis described the basic principles of the function and the geometric boundary conditions for the construction of ventilated external walls. The proposed revision of DIN 18516-1:2008-09 will again based on the fundamental results of his work. Meanwhile, further work has been carried out on various aspects, including the work by Janser and Marquardt on wind load assumptions and the corrosion-inhibiting effect of ventilated external walls. Ventilated external facings can be retrofitted to damaged walls in large-panel buildings to improve thermal insulation, as a remedial measure for joint defects, and in order to improve corrosion protection. This paper discusses the physical mechanisms relating to wind load reduction and corrosion protection. (Abstract Copyright [2008], Wiley Periodicals, Inc.) [German] Die grundlegende Arbeit ueber die Wirkungsweise und die geometrischen Randbedingungen bei der Konstruktion hinterluefteter Aussenwandkonstruktionen hat Karl Gertis mit seiner Habilitationsschrift verfasst. Auch in der geplanten Neufassung von DIN 18516-1:2008-09 wird auf die grundlegenden Ergebnisse seiner Arbeit unveraendert zugegriffen werden. Weiterfuehrende Arbeiten wurden unter anderem ueber die anzusetzenden Windlastannahmen und die korrosionshemmende Wirkung hinterluefteter Aussenwaende von Janser und Marquardt durchgefuehrt. Durch die nachtraegliche Montage von hinterluefteten Aussenwandkonstruktionen auf die geschaedigten Waende des Grosstafelbaus kann sowohl die Waermedaemmung verbessert werden als auch eine Sanierung der Fugen erfolgen; insbesondere wird aber durch das Aufbringen hinterluefteter Aussenwandkonstruktionen der Korrosionsschutz wesentlich verbessert. Im Folgenden werden die Wirkmechanismen hinsichtlich der Reduzierung der Windlast und des Korrosionsschutzes beschrieben. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  14. Twee vroeë reaksies van Gereformeerde kant op Karl Barth

    Directory of Open Access Journals (Sweden)

    B. J. Engelbrecht

    1986-06-01

    Full Text Available In 1919 het die eerste uitgawe van die epogmakende “Romerbrief” van Karl Barth verskyn. Van die tweede druk in 1922 sê hy dat “kein Stein mehr auf dem andem” gelaat is nie. So opspraakwekkend was hierdie boek dat in 1929 die 5de druk van die tweede, radikaal-hersiene uitgawe verskyn het. Intussen het nog ander werke van Barth en selfs oor Barth verskyn. 0ns noem o.a. sy Der Christ in der Gesellschaft (1920; Das Wort Gottes und die Theologie (1924; Vom Christlichen Leben (1926; Auferstehung der Toten (2. Aufl. 1927, sy preke saam met Eduard Thurneysen Komm Schopfer Geist, (Dritt Aufl., 7-9 Tausend(! 1926. Maar 1927 was veral belangrik vanweë die verskyning van Barth se eerste Dogmatiekboek: “Die Christliche Dogmatik im Entwurf. 1 Die Lehre vom Worte Gottes. Prolegomena zur Christlichen Dogmatik” . Voor dié datum het dwarsoor die wêreld, maar ook in Nederland wye reaksie op sy teologie ontstaan. In 1926 skryf Max Strauch sy “Theologie Karl Barth’s”, terwyl Haitjema in Nederland ook in 1926 sy Barth boek die lig laat sien (Prof. dr. Th. L. Haitjema, Karl Barth, Wageningen 1926. Ander Nederlanders wat gereageer het, was drr. A. H. de Hartog, V. Hepp, Ph. Kohnstamm en di. D. Tromp en 0. Noordmans.

  15. Potentiometric titration of gold, platinum, and some other precious metals

    Energy Technology Data Exchange (ETDEWEB)

    Selig, W.S.

    1991-02-04

    Gold, platinum, and several other platinum metals can be determined by titration with cetylpyridinium chloride (CPC). CPC forms a precipitate with AuCl{sub 4}{sup {minus}} and PtCl{sub 6}{sup 2{minus}}. Differentiation of AuCl{sub 4{minus}} and PtCl{sub 6}{sup 2{minus}} with this titrant is not possible; however, their sum can be determined. Titration with tetraphenylarsonium chloride at pH 1 is selective for tetrachloroaurate, which thus can be determined in the presence of hexachloroplatinate. Hexachloroosmate(IV), tetrachloroplatinite(II), tetrachloropalladate(II), hexachloropalladate(IV), and hexachloroiridate(IV) can also be determined potentiometrically vs. CPC. The indicating electrode is prepared by coating a spectroscopic graphite rod with a solution of poly(vinyl chloride) (PVC) and dioctylphthalate (DOP) in tetrahydrofuran (THF). Gold in gold cyanide plating baths and in potassium aurocyanide can be determined by potentiometric titration vs standard silver nitrate, using a silver ion-selective indicating electrode. The monovalent gold need not be converted to the trivalent state with aqua regia, resulting in a considerable saving of time and effort. Free cyanide and aurocyanide can be titrated sequentially by this method. Chloride does not interfere and can, in fact, also be sequentially determined. 17 refs., 2 figs., 3 tabs.

  16. Isothermal Titration Calorimetry Can Provide Critical Thinking Opportunities

    Science.gov (United States)

    Moore, Dale E.; Goode, David R.; Seney, Caryn S.; Boatwright, Jennifer M.

    2016-01-01

    College chemistry faculties might not have considered including isothermal titration calorimetry (ITC) in their majors' curriculum because experimental data from this instrumental method are often analyzed via automation (software). However, the software-based data analysis can be replaced with a spreadsheet-based analysis that is readily…

  17. Isothermal Titration Calorimetry Can Provide Critical Thinking Opportunities

    Science.gov (United States)

    Moore, Dale E.; Goode, David R.; Seney, Caryn S.; Boatwright, Jennifer M.

    2016-01-01

    College chemistry faculties might not have considered including isothermal titration calorimetry (ITC) in their majors' curriculum because experimental data from this instrumental method are often analyzed via automation (software). However, the software-based data analysis can be replaced with a spreadsheet-based analysis that is readily…

  18. Modeling of titration experiments by a reactive transport model

    Institute of Scientific and Technical Information of China (English)

    Ma Hongyun; Samper Javier; Xin Xin

    2011-01-01

    Acid mine drainage (AMD) is commonly treated by neutralization with alkaline substances. This treatment is supported by titration experiments that illustrate the buffering mechanisms and estimate the base neutralization capacity (BNC) of the AMD. Detailed explanation of titration curves requires modeling with a hydro-chemical model. In this study the titration curves of water samples from the drainage of the As Pontes mine and the corresponding dumps have been investigated and six buffers are selected by analyzing those curves. Titration curves have been simulated by a reactive transport model to discover the detailed buffering mechanisms. These simulations show seven regions involving different buffering mechanism. The BNC is primarily from buffers of dissolved Fe, Al and hydrogen sulfate. The BNC can be approximated by: BNC = 3(CFe + CAl) + 0.05Csulfate, where the units are mol/L. The BNC of the sample from the mine is 9.25 × 10-3 mol/L and that of the dumps sample is 1.28 × 10-2 mol/L.

  19. Titration of Isolated Cell Walls of Lemna minor L 1

    Science.gov (United States)

    Morvan, Claudine; Demarty, Maurice; Thellier, Michel

    1979-01-01

    A theoretical model has been built to bypass the equation of titration of the cell wall. This equation, which is an extension of the Henderson-Hasselbach equation, underlines the importance of the exchange constant, the ionic strength as well as the rate of neutralization. The model is restricted to the case when the ionization degree is equal to the neutralization degree. The shape of the titration curve is shown to be strongly dependent on the valency of the base used. Experimental results have shown that isolated cell walls bear at least two kinds of sites. The first sites which are titrated after a short time of equilibration are attributed to polyuronic acids (capacity: 0.3 milliequivalents per gram fresh cell walls). The second sites, are obtained after a long time of equilibration (capacity: 1.2 to 1.3 milliequivalents per gram, fresh cell walls). Titrations have been performed with different bases [KOH, NaOH, and Ca(OH)2] and under different ionic strengths. The results obtained with NaOH and KOH do not exhibit any difference of selectivity. Conversely, the sites have a much bigger affinity for the Ca2+ ions than for the monovalent ones. The apparent pKa of the uronic acids was estimated to lie between 3.0 and 3.4; this is consistent with the values obtained with polyuronic acid solutions. PMID:16660868

  20. potentiometric titration curves of aluminium salt solutions and its ...

    African Journals Online (AJOL)

    a

    In addition, the changes of critical points reflect the influence of experiment ... organic acid radical on the titration curves and its critical points were observed. ..... According to the theory of hard and soft acids and bases (HSAB), Al3+ ion ...

  1. Analysis of the Purity of Cetrimide by Titrations

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov; Rasmussen, Claus/Dallerup; Nielsen, Hans/Boye

    2006-01-01

    The purity of cetrimide, trimethyl tetradecyl ammonium bromide (TTAB), that is an important preservative of many cosmetic and pharmaceutical products, was determined by three independent methods of titration. Traditionally, cetrimide was analysed by an assay method of the European Pharmacopoeia (Ph...

  2. Aging increases upper airway collapsibility in Fischer 344 rats.

    Science.gov (United States)

    Ray, Andrew D; Ogasa, Toshiyuki; Magalang, Ulysses J; Krasney, John A; Farkas, Gaspar A

    2008-11-01

    The upper airway muscles play an important role in maintaining upper airway collapsibility, and the incidence of sleep-disordered breathing increases with age. We hypothesize that the increase in airway collapsibility with increasing age can be linked to changes in upper airway muscle mechanics and structure. Eight young (Y: 6 mo) and eight old (O: 30 mo) Fischer 344 rats were anesthetized and mechanically ventilated, and the pharyngeal pressure associated with flow limitation (Pcrit) was measured 1) with the hypoglossal (cnXII) nerve intact, 2) following bilateral cnXII denervation, and 3) during cnXII stimulation. With the cnXII intact, the upper airways of older rats were more collapsible compared with their younger counterparts [Pcrit = -7.1 +/- 0.6 (SE) vs. -9.5 +/- 0.7 cmH2O, respectively; P = 0.033]. CnXII denervation resulted in an increase in Pcrit such that Pcrit became similar in both groups (O: -4.2 +/- 0.5 cmH2O; Y: -5.4 +/- 0.5 cmH2O). In all rats, cnXII stimulation decreased Pcrit (less collapsible) in both groups (O: -11.3 +/- 1.0 cmH2O; Y: -10.2 +/- 1.0 cmH2O). The myosin heavy chain composition of the genioglossus muscle demonstrated a decrease in the percentage of the IIb isoform (38.3 +/- 2.5 vs. 21.7 +/- 1.7%; P collapsible with age and that the increase in upper airway collapsibility with age is likely related to altered neural control rather than to primary alterations in upper airway muscle structure and function.

  3. Neck Kaposiform haemangioendothelioma in a Fischer's lovebird (Agapornis fischeri).

    Science.gov (United States)

    Rossi, Giacomo; Galosi, Livio; Berardi, Sara; Piano, Maria Assunta; Robino, Patrizia; Rose, Timothy; Calabrò, Maria Luisa

    2016-06-01

    A six-year-old female Fischer's lovebird (Agapornis fischeri) presented at necropsy with a cutaneous mass on the neck, 3.5cm in diameter, yielding and with blood content. Histopathological findings showed a neoplasm characterized by proliferation of vascular endothelial cells. The histology of the mass revealed a multinodular, focally infiltrating tumor. Deeper dermal nodules were made of spindle cells forming vascular slits reminiscent of the histology seen in Kaposi's sarcoma (KS). More superficially located dermal nodules consisted of small blood vessels, with histology resembling capillary hemangioma. The spindle cells and capillaries were strongly positive for Vimentin, endothelial cell marker CD31, and negative for sarcomeric α-smooth muscle actin (α-SMA). Intravascular platelet trapping and Periodic acid-Schiff (PAS)-positive hyaline globules were also observed. Differential diagnosis included Kaposi's sarcoma, capillary haemangioma, spindle cell haemangioendothelioma, and epithelioid haemangioendothelioma. Based on morphological and immunohistochemical findings, the tumor was diagnosed as a cutaneous Kaposiform haemangioendothelioma (KHE), a rare, low-grade malignant vascular neoplasm. Other organs showed no abnormalities. PCR amplifications, conducted using Kaposi's sarcoma-associated herpesvirus (KSHV)-specific primers and degenerate sets of primers designed to detect and characterize members of the Herpesviridae, on DNA extracted from tumor tissue and from whole blood failed to amplify any KSHV-related sequence. Moreover, no specific signal was obtained using primers for detection of psittacine herpesvirus, known to be linked to Pacheco's disease in parrots. To the best of our knowledge, this unusual case is the third report of KHE in a non-human animal species, the first described in a bird. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Fischer-Tropsch synthesis in supercritical fluids. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Akgerman, A.; Bukur, D.B.

    1998-12-31

    The objective of this study was to investigate Fischer-Tropsch Synthesis (FTS) in the supercritical phase employing a commercial precipitated iron catalysts. As the supercritical fluid the authors used propane and n-hexane. The catalyst had a nominal composition of 100 Fe/5 Cu/4.2 K/25 SiO{sub 2} on mass basis and was used in a fixed bed reactor under both normal (conventional) and supercritical conditions. Experimental data were obtained at different temperatures (235 C, 250 C, and 260 C) and synthesis gas feed compositions (H{sub 2}/CO molar feed ratio of 0.67, 1.0 and 2.0) in both modes of operation under steady state conditions. The authors compared the performance of the precipitated iron catalyst in the supercritical phase, with the data obtained in gas phase (fixed bed reactor) and slurry phase (STS reactor). Comparisons were made in terms of bulk catalyst activity and various aspects of product selectivity (e.g. lumped hydrocarbon distribution and olefin content as a function of carbon number). In order to gain better understanding of the role of intraparticle mass transfer during FTS under conventional or supercritical conditions, the authors have measured diffusivities of representative hydrocarbon products in supercritical fluids, as well as their effective diffusion rates into the pores of catalyst at the reaction conditions. They constructed a Taylor dispersion apparatus to measure diffusion coefficients of hydrocarbon products of FTS in sub and supercritical ethane, propane, and hexane. In addition, they developed a tracer response technique to measure the effective diffusivities in the catalyst pores at the same conditions. Based on these results they have developed an equation for prediction of diffusion in supercritical fluids, which is based on the rough hard sphere theory.

  5. Recent advances on Fischer-Tropsch synthesis in micro-reactor%微反应器技术在Fischer-Tropsch合成中的应用进展

    Institute of Scientific and Technical Information of China (English)

    徐润; 胡志海; 聂红

    2016-01-01

    微反应器可以通过改善传质和传热而强化反应过程,为Fischer-Tropsch合成技术的发展提供了新的机遇。本文简要回顾了微反应器的研究及发展过程,从微反应器的本质特点着手,介绍了微反应器技术在Fischer-Tropsch合成中的应用进展。Fischer-Tropsch合成微反应器结构经历了从单通道、多通道、复合通道结构的研究过程,催化剂也开发有填充型和涂覆型两类。根据微反应器的特点,催化剂开发也取得了显著进步,与传统催化剂相比,微通道催化剂的活性可以达到固定床的8~10倍。反应器模型和数值模拟工作可以辅助实验研究,提供温度、浓度、压力等分布参数,有利于反应器设计。最后介绍了目前微反应器 Fischer-Tropsch 合成技术的中试及工业应用情况。通过对上述内容的总结,对微反应器Fischer-Tropsch合成研究和发展进行了展望。%The mass transfer and heat transfer of the chemical reaction can be improved by micro-reactor technology,which provides a new platform for Fischer-Tropsch synthesis. This paper reviews the researches and development of micro-reactor technology in the recent year and the Fischer-Tropsch synthesis in micro-reactor. The structure researches of micro-reaction devices have gone through the developments of single channel,multi channel and complex channel. The catalysts can be divided into two categories of micro particle and wall coating. Along with developments of micro reactor,the catalysts studies have also made significant progress. The activity of catalysts in micro-reaction device is 8 to 10 times higher than that in fixed-bed reactor. The studies of numerical analysis are summarized. This paper also introduces the status of pilot test and commercialization of Fischer-Tropsch synthesis in micro-reactor. It is expected the Fischer-Tropsch synthesis in micro-reactor will have a deeper development in future.

  6. When acid-base titrations are carried out in unusual conditions

    OpenAIRE

    Domenico De Marco; Rocco De Marco

    2012-01-01

    Uncommon aspects in acid-base titrations are presented, which occur in titrations between both mono- and/or poly-functional acid and bases but are rarely introduced in ordinary analytical chemistry courses.

  7. 用卡氏库仑法测定二氧化铀中的水分%Determination of water content in uranium dioxide with Karl Fisher coulometer

    Institute of Scientific and Technical Information of China (English)

    王春叶; 杜桂荣; 谢树军; 李晓红; 朱小良

    2011-01-01

    The method of determining water content in uranium dioxide with Karl Fisher coulometer is introduced, and the instrument conditions were optimized. Air is taken as carrier gas, carrier gas f low rate is 40-60 mL/min, the temperature of Cassette furnace is 200 ℃, stirring rate of titration cell is 300-900 r/min, the extraction time is 800 s. Under the above conditions, water content in uranium dioxide was determined. The detection limit of the method is 38 μg/g, the relative standard deviation is less than 1. 76%(n = 6), and standard addition recovery is 93. 6%-99.1%.%介绍测定二氧化铀中水分的卡尔费休库仑法及条件参数的优化.采用以下条件参数对二氧化铀中的水分进行测定:空气作载气,载气流速为60 mL/min,卡氏炉温度为200℃,滴定池的搅拌速度为600 r/min,萃取时间为800 s.方法检出限为38 μg/g,6次平行测定的相对标准偏差为1.76%,标准加入的回收率为93.6%~99.1%.

  8. Effect of cobalt loading on reducibility,dispersion and crystallite size of Co/Al2O3 Fischer-Tropsch catalyst

    Institute of Scientific and Technical Information of China (English)

    熊海峰; 张煜华; 李金林; 古映莹

    2004-01-01

    Co/Al2O3 Fischer-Tropsch synthesis catalysts with different cobalt loadings were prepared using incipient wetness impregnation method. The effects of cobalt loading on the properties of catalysts were studied by means of X-ray diffraction (XRD), temperature programmed reduction (TPR), hydrogen temperature programmed desorption (H2-TPD) and O2 titration. Co-support compound formation can be detected in catalyst system by XRD.For the Co/Al2 O3 catalysts with low cobalt loading, CoAl2 O4 phase appears visibly. Two different reduction regions can be presented for Co/Al2O3 catalysts, which belong to Co3O4 crystallites (reduction at 320 ℃ ) and cobalt oxidealumina interaction species (reduction at above 400 C ). Increasing Co loading results in the increase of Co3 O4 crystallite size. The reduced Co/Al2 O3 catalysts have two adsorption sites, and cobalt loading greatly influences the adsorption behavior. With the increase of cobalt loading, the amount of low temperature adsorption is increased, the amount of high temperature adsorption is decreased, and the percentage reduction and cobalt crystallite size are increased.

  9. Effect of the pore size of Co/SBA-15 isomorphically substituted with zirconium on its catalytic performance in Fischer-Tropsch synthesis

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Cobalt catalysts supported on a series of mesoporous SBA-15 materials isomorphically substituted with zirconium (Zr/Si atomic ratio=1/20) with different pore sizes (5.7 nm,7.8 nm,11.6 nm,17.6 nm) have been synthesized.The catalysts were characterized by transmission electron microscopy,29 Si solid state magic angle spinning (MAS)NMR,N2 adsorption-desorption measurements,X-ray powder diffraction,X-ray photoelectron spectroscopy,H2-temperature programmed reduction,H2-temperature programmed desorption and O2 titrations.The results indicated that larger pore size led to weaker interactions between cobalt and the supports which lowered the temperature of both reduction steps (Co3O4 → CoO and CoO→ Co0).The catalytic performances of the catalysts in Fischer-Tropsch synthesis (FTS) were tested in a fixed bed reactor.It was found that the FTS catalytic activity and product selectivity depended strongly on the pore size of the catalysts.The catalyst with a pore size of 7.8 nm showed the best FTS activity,and the catalyst with a pore size of 17.6 nm showed the highest selectivity to C12-C20 and C20+ hydrocarbons.

  10. Physiatrie and German maternal feminism: Dr. Anna Fischer-Dückelmann critiques academic medicine.

    Science.gov (United States)

    Meyer, Paulette

    2006-01-01

    Alternative medicine and reform strategies made Anna Fischer-Dückelmann a most controversial, notorious, and widely read women doctor before World War I. She published a dozen titles in 13 languages asserting that national well-being depended on maternal prowess. To her critics, Fischer-Dückelmann's commitment to medical self-help and practices of Physiatrie amounted to medical quackery. Her career has been largely unexamined, yet her feminist critiques and social concerns are not far removed from modern social medicine. For this pioneering doctor, treating physical and emotional ills and promoting the health of families were first steps toward healing the divisions of a world at war.

  11. Fischer-Tropsch synthesis. Evaluation of an aluminum small channel reactor.

    Science.gov (United States)

    Sparks, D E; Vallee, S; Jia, Zhijun; Shafer, W D; Davis, B H

    2017-02-10

    Fischer-Tropsch synthesis was conducted in a small channel compact heat exchange reactor that was constructed of aluminum. While limited to lower temperature-pressure regions of the Fischer-Tropsch synthesis, the reactor could be operated in an isothermal mode with nearly a constant temperature along the length of the channel. The results obtained with the compact heat exchange reactor were similar to those obtained in the isothermal continuous stirred tank reactor, with respect to both activity and selectivity. Following a planned or unplanned shutdown, the reactor could be restarted to produce essentially the same catalytic activity and selectivity as before the shutdown.

  12. Fischer-Tropsch Reaction Kinetics of Cobalt Catalyst in Supercritical Phase

    Institute of Scientific and Technical Information of China (English)

    Abdullah Irankhah; Ali Haghtalab; Ebrahim Vasheghani Farahani; Kambiz Sadaghianizadeh

    2007-01-01

    Fischer-Tropsch synthesis under supercritical phase condition was examined in a continuous and a high-pressure fixed bed reactor by employing a cobalt catalyst (Co-Ru/γ-Al2O3). An integral reactor model involving Fischer-Tropsch reaction kinetics in the supercritical fluid n-hexane was used to describe the overall performance. On the basis of Langmuir-Hinshelwood-Hougen-Watson (LHHW) model, the reaction rate constants were obtained for the rate equations of CO conversion to CH4 formation under supercritical conditions.

  13. The Acid-Base Titration of a Very Weak Acid: Boric Acid

    Science.gov (United States)

    Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.

    2012-01-01

    A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

  14. The Acid-Base Titration of a Very Weak Acid: Boric Acid

    Science.gov (United States)

    Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.

    2012-01-01

    A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

  15. A contribuição de Karl Polanyi para a sociologia do desenvolvimento rural The contribution of Karl Polanyi for the rural development sociology

    Directory of Open Access Journals (Sweden)

    Sergio Schneider

    2011-08-01

    Full Text Available O ensaio aborda a importância da redescoberta do pensamento de Karl Polanyi e de sua crítica à "sociedade de mercado" na retomada dos estudos e debates sobre o desenvolvimento (rural. Após uma apresentação geral do quadro teórico e analítico de Polanyi, buscamos utilizar seus conceitos para interpretar a dinâmica da mercantilização dos meios de vida e das formas sociais de trabalho e produção no espaço rural, bem como dos sistemas agroalimentares no capitalismo contemporâneo. Com base nestas proposições, refletimos sobre o papel dos atores sociais e das instituições nos processos de mudança social em geral e os de desenvolvimento rural em particular. Finalizamos, propondo algumas potencialidades dessa abordagem para os estudos sobre desenvolvimento rural no Brasil.The essay deals with the importance of the rediscovery of Karl Polanyi's thinking and of his criticism of the "market society" in resuming (rural development studies and debates. Following an overall presentation of Polanyi's theoretical and analytical framework, we look for using his concepts to interpret the commoditization dynamics of the rural livelihoods and the social forms of labor and production in the rural space, as well as the commoditization of the agri-food systems in the contemporary capitalism. Based on these statements, we reflect about the role of social actors and institutions in the processes of social change at large and of rural development in particular. And, finally, we propose some potentialities of this approach for the rural development studies in Brazil.

  16. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYSTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    Dragomir B. Bukur; Gilbert F. Froment; Tomasz Olewski

    2005-09-29

    This report covers the third year of this research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis (FTS) on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict molar flow rates and concentrations of all reactants and major product species (H{sub 2}O, CO{sub 2}, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the reporting period we utilized experimental data from the STSR, that were obtained during the first two years of the project, to perform vapor-liquid equilibrium (VLE) calculations and estimate kinetic parameters. We used a modified Peng-Robinson (PR) equation of state (EOS) with estimated values of binary interaction coefficients for the VLE calculations. Calculated vapor phase compositions were in excellent agreement with experimental values from the STSR under reaction conditions. Occasional discrepancies (for some of the experimental data) between calculated and experimental values of the liquid phase composition were ascribed to experimental errors. The VLE calculations show that the vapor and the liquid are in thermodynamic equilibrium under reaction conditions. Also, we have successfully applied the Levenberg-Marquardt method (Marquardt, 1963) to estimate parameters of a kinetic model proposed earlier by Lox and Froment (1993b) for FTS on an iron catalyst. This kinetic model is well suited for initial studies where the main goal is to learn techniques for parameter estimation and statistical analysis of estimated values of model parameters. It predicts that the chain growth parameter ({alpha}) and olefin to paraffin ratio are independent of carbon number, whereas our experimental data show that they vary with the carbon number

  17. Subtask 3.4 - Fischer - Tropsch Fuels Development

    Energy Technology Data Exchange (ETDEWEB)

    Strege, Joshua; Snyder, Anthony; Laumb, Jason; Stanislowski, Joshua; Swanson, Michael

    2012-05-01

    Under Subtask 3.4, the Energy & Environmental Research Center (EERC) examined the opportunities and challenges facing FischerTropsch (FT) technology in the United States today. Work was completed in two distinct budget periods (BPs). In BP1, the EERC examined the technical feasibility of using modern warm-gas cleanup techniques for FT synthesis. FT synthesis is typically done using more expensive and complex cold-gas sweetening. Warm-gas cleanup could greatly reduce capital and operating costs, making FT synthesis more attractive for domestic fuel production. Syngas was generated from a variety of coal and biomass types; cleaned of sulfur, moisture, and condensables; and then passed over a pilot-scale FT catalyst bed. Laboratory and modeling work done in support of the pilot-scale effort suggested that the catalyst was performing suboptimally with warm-gas cleanup. Long-term trends showed that the catalyst was also quickly deactivating. In BP3, the EERC compared FT catalyst results using warm-gas cleanup to results using cold-gas sweetening. A gas-sweetening absorption system (GSAS) was designed, modeled, and constructed to sweeten syngas between the gasifier and the pilot-scale FT reactor. Results verified that the catalyst performed much better with gas sweetening than it had with warm-gas cleanup. The catalyst also showed no signs of rapid deactivation when the GSAS was running. Laboratory tests in support of this effort verified that the catalyst had deactivated quickly in BP1 because of exposure to syngas, not because of any design flaw with the pilot-scale FT reactor itself. Based on these results, the EERC concludes that the two biggest issues with using syngas treated with warm-gas cleanup for FT synthesis are high concentrations of CO{sub 2} and volatile organic matter. Other catalysts tested by the EERC may be more tolerant of CO{sub 2}, but volatile matter removal is critical to ensuring long-term FT catalyst operation. This subtask was funded through

  18. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    Dragomir B. Bukur; Gilbert F. Froment; Tomasz Olewski

    2006-09-29

    This report covers the fourth year of a research project conducted under the University Coal Research Program. The overall objective of this project is to develop a comprehensive kinetic model for slurry-phase Fischer-Tropsch synthesis (FTS) employing iron-based catalysts. This model will be validated with experimental data obtained in a stirred-tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict molar flow rates and concentrations of all reactants and major product species (water, carbon dioxide, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the fourth year of the project, an analysis of experimental data collected during the second year of this project was performed. Kinetic parameters were estimated utilizing product distributions from 27 mass balances. During the reporting period two kinetic models were employed: a comprehensive kinetic model of Dr. Li and co-workers (Yang et al., 2003) and a hydrocarbon selectivity model of Van der Laan and Beenackers (1998, 1999) The kinetic model of Yang et al. (2003) has 24 parameters (20 parameters for hydrocarbon formation, and 4 parameters for the water-gas-shift (WGS) reaction). Kinetic parameters for the WGS reaction and FTS synthesis were estimated first separately, and then simultaneously. The estimation of these kinetic parameters employed the Levenberg-Marquardt (LM) method and the trust-region reflective Newton large-scale (LS) method. A genetic algorithm (GA) was incorporated into estimation of parameters for FTS reaction to provide initial estimates of model parameters. All reaction rate constants and activation energies were found to be positive, but at the 95% confidence level the intervals were large. Agreement between predicted and experimental reaction rates has been fair to good. Light hydrocarbons are predicted fairly accurately, whereas the model underpredicts values of higher molecular weight

  19. Applications of isothermal titration calorimetry in protein science.

    Science.gov (United States)

    Liang, Yi

    2008-07-01

    During the past decade, isothermal titration calorimetry (ITC) has developed from a specialist method for understanding molecular interactions and other biological processes within cells to a more robust, widely used method. Nowadays, ITC is used to investigate all types of protein interactions, including protein-protein interactions, protein-DNA/RNA interactions, protein-small molecule interactions and enzyme kinetics; it provides a direct route to the complete thermodynamic characterization of protein interactions. This review concentrates on the new applications of ITC in protein folding and misfolding, its traditional application in protein interactions, and an overview of what can be achieved in the field of protein science using this method and what developments are likely to occur in the near future. Also, this review discusses some new developments of ITC method in protein science, such as the reverse titration of ITC and the displacement method of ITC.

  20. Monitoring RNA-ligand interactions using isothermal titration calorimetry.

    Science.gov (United States)

    Gilbert, Sunny D; Batey, Robert T

    2009-01-01

    Isothermal titration calorimetry (ITC) is a biophysical technique that measures the heat evolved or absorbed during a reaction to report the enthalpy, entropy, stoichiometry of binding, and equilibrium association constant. A significant advantage of ITC over other methods is that it can be readily applied to almost any RNA-ligand complex without having to label either molecule and can be performed under a broad range of pH, temperature, and ionic concentrations. During our application of ITC to investigate the thermodynamic details of the interaction of a variety of compounds with the purine riboswitch, we have explored and optimized experimental parameters that yield the most useful and reproducible results for RNAs. In this chapter, we detail this method using the titration of an adenine-binding RNA with 2,6-diaminopurine (DAP) as a practical example. Our insights should be generally applicable to observing the interactions of a broad range of molecules with structured RNAs.

  1. Applications of isothermal titration calorimetry in protein science

    Institute of Scientific and Technical Information of China (English)

    Yi Liang

    2008-01-01

    During the past decade,isothermal titration calorimetry (ITC)has developed from a specialist method for understanding molecular interactions and other biological processes within cells to a more robust,widely used method.Nowadays,ITC is used to investigate all types of protein interactions,including protein-protein interactions,protein-DNA/RNA interactions,protein-small molecule interactions and enzyme kinetics;it provides a direct route to the complete thermodynamic characterization of protein interactions.This review concentrates on the new applications of ITC in protein folding and misfolding,its traditional application in protein interactions,and an overview of what can be achieved in the field of protein science using this method and what developments are likely to occur in the near future.Also,this review discusses some new developments of ITC method in protein science,such as the reverse titration of ITC and the displacement method of ITC.

  2. Monitoring assembly of ribonucleoprotein complexes by isothermal titration calorimetry

    OpenAIRE

    Recht, Michael I; Ryder, Sean P.; Williamson, James R.

    2008-01-01

    Isothermal titration calorimetry (ITC) is a useful technique to study RNA-protein interactions, as it provides the only method by which the thermodynamic parameters of free energy, enthalpy, and entropy can be directly determined. This chapter presents a general procedure for studying RNA-protein interactions using ITC, and gives specific examples for monitoring the binding of Caenorhabditis elegans GLD-1 STAR domain to TGE RNA and the binding of Aquifex aeolicus S6:S18 ribosomal protein hete...

  3. Solubility of strontium-substituted apatite by solid titration

    OpenAIRE

    Pan, HB; Darvell, BW; Luk, KDK; Lu, WW; Li, ZY; Lam, WM; Wong, JC

    2009-01-01

    Solid titration was used to explore the solubility isotherms of partially (Srx-HAp, x = 1, 5, 10, 40, 60 mol.%) and fully substituted strontium hydroxyapatite (Sr-HAp). Solubility increased with increasing strontium content. No phase other than strontium-substituted HAp, corresponding to the original titrant, was detected in the solid present at equilibrium; in particular, dicalcium hydrogen phosphate was not detected at low pH. The increase in solubility with strontium content is interpreted...

  4. A titration microcalorimeter and the vesicle of mixed surfactants

    Institute of Scientific and Technical Information of China (English)

    白光月[1; 王玉洁[2; 王金本[3; 杨冠英[4; 韩布兴[5; 闫海科[6

    2000-01-01

    A titration microcalorimeter with the sample cells of 1 mL and 3 mL volume was constructed by combining LKB-2107 ampule microcalorimeter with an improved Thermometric titration microcalorimeter. Its sensitivity and precision were tested with the baseline noise and stability, the measurement of energy equivalent, and the linear relation of electric energy and integral area as the function of voltage (V)-time (f). Its accuracy was demonstrated by measuring the dilution enthalpy of a concentrated sucrose solution and the micelle-forming enthalpy of sodium dodecyl sulfate (SDS) in aqueous solution respectively. At the same time, the enthalpy of interaction between SDS and didodecyldimethylammonium bromide (DDAB) was measured by using the titration microcalorimeter, and the phase behavior of SDS-DDAB aqueous mixture was discussed. The microcalorimetric results show that the enthalpy of interaction between SDS and DDAB micelles is -29.53 kJ/mol, the enthalpy of formation of 1:1 SDS-DDAB salt is -125.8 kJ/mol,

  5. A titration microcalorimeter and the vesicle of mixed surfactants

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A titration microcalorimeter with the sample cells of 1 mL and 3 mL volume was constructed by combining LKB-2107 ampule microcalorimeter with an improved Thermometric titration microcalorimeter. Its sensitivity and precision were tested with the baseline noise and stability, the measurement of energy equivalent, and the linear relation of electric energy and integral area as the function of voltage (V )-time (t ). Its accuracy was demonstrated by measuring the dilution enthalpy of a concentrated sucrose solution and the micelle-forming enthalpy of sodium dodecyl sulfate (SDS) in aqueous solution respectively. At the same time, the enthalpy of interaction between SDS and didodecyldimethylammonium bromide (DDAB) was measured by using the titration microcalorimeter, and the phase behavior of SDS-DDAB aqueous mixture was discussed. The microcalorimetric results show that the enthalpy of interaction between SDS and DDAB micelles is ?29.53 kJ/mol, the enthalpy of formation of 1:1 SDS-DDAB salt is ?125.8 kJ/mol, the vesicle-forming enthalpy of SDS-DDAB is 41.23 kJ/mol, and the enthalpy of phase transition from vesicles to SDS rich micelle is 32.10 kJ/mol.

  6. Impact of Residual Inducer on Titratable Expression Systems.

    Directory of Open Access Journals (Sweden)

    Taliman Afroz

    Full Text Available Inducible expression systems are widely employed for the titratable control of gene expression, yet molecules inadvertently present in the growth medium or synthesized by the host cells can alter the response profile of some of these systems. Here, we explored the quantitative impact of these residual inducers on the apparent response properties of inducible systems. Using a simple mathematical model, we found that the presence of residual inducer shrinks the apparent dynamic range and causes the apparent Hill coefficient to converge to one. We also found that activating systems were more sensitive than repressing systems to the presence of residual inducer and the response parameters were most heavily dependent on the original Hill coefficient. Experimental interrogation of common titratable systems based on an L-arabinose inducible promoter or a thiamine pyrophosphate-repressing riboswitch in Escherichia coli confirmed the predicted trends. We finally found that residual inducer had a distinct effect on "all-or-none" systems, which exhibited increased sensitivity to the added inducer until becoming fully induced. Our findings indicate that residual inducer or repressor alters the quantitative response properties of titratable systems, impacting their utility for scientific discovery and pathway engineering.

  7. From Fischer Tropsch raw products to Fischer Tropsch fuels. Development of an upgrading model and application to XtL processes

    Energy Technology Data Exchange (ETDEWEB)

    Beiermann, D. [Volkswagen AG, Wolfsburg (Germany)

    2007-07-01

    Within the EU-project RENEW (supported under the European Commission's 6th framework programme) an upgrading model for the conversion of Fischer Tropsch rawproducts to Fischer Tropsch fuels was developed and simulated with the process simulation software CHEMCAD. The model allowed - based on process parameters of the inputstreams - the calculation of the resulting amounts of diesel, naphtha and electricity out of the arising offgases. In addition the energy and the hydrogen demand for the upgrading process can be calculated. Furthermore a classification in thermal and electric power demand and production respectively is done. A plausibility check by means of energy consumption of different oil refineries validated the developed model. Concluding a TCI cost calculation shows the corresponding capital costs of such an upgrading unit. So beside closing the mass and energy balance, the developed model can also be used for economic calculation of XtL concepts with the aim of maximised liquid fuel production, starting from Fischer Tropsch rawproducts. (orig.)

  8. El huracán Karl: concepciones sobre su origen en una comunidad de Veracruz

    OpenAIRE

    Arturo Marinero Heredia; María José García Oramas

    2015-01-01

    Se analizan las concepciones e ideas de pobladores adultos sobre las afectaciones sufridas por el huracán Karl en 2010, en el municipio de La Antigua, Veracruz. Los datos se obtuvieron de entrevistas a informantes claves y grupos focales, además de la revisión de notas periodisticas. Se observa que las concepciones e ideas sobre el origen del desastre las adjudican a las fuerzas naturales, espirituales o religiosas sin reconocer la responsabilidad de las autoridades encargadas de elaborar pol...

  9. El huracán Karl: concepciones sobre su origen en una comunidad de Veracruz

    OpenAIRE

    Arturo Marinero Heredia; María José García Oramas

    2015-01-01

    Se analizan las concepciones e ideas de pobladores adultos sobre las afectaciones sufridas por el huracán Karl en 2010, en el municipio de La Antigua, Veracruz. Los datos se obtuvieron de entrevistas a informantes claves y grupos focales, además de la revisión de notas periodisticas. Se observa que las concepciones e ideas sobre el origen del desastre las adjudican a las fuerzas naturales, espirituales o religiosas sin reconocer la responsabilidad de las autoridades encargadas de elaborar pol...

  10. Karl R. Popper'ın Tarihsicilik Eleştirisi

    OpenAIRE

    Rıza Bakış; Eyüp Alsancak

    2016-01-01

    ABSTRACT: Karl R. Popper is an important philosopher of science of 20th Century and is known in this field through his theory of falsification. But the critical theory of rationality is indeed his basic theory and it can be seen in his whole idea.  Critique of historicism also contains his views on the social and political philosophy in a systematic context in relation to them. Popper embodied his views about the historicism through human-centered thoughts of philosophers such as Plato, Arist...

  11. REALISMO E PLURALISMO: A FILOSOFIA DA CIÊNCIA DE KARL R. POPPER

    OpenAIRE

    Mateus Romanini

    2012-01-01

    O presente trabalho tem por objetivo principal apresentar uma interpretação da obra de Karl Raimund Popper que leva em consideração dois problemas e suas respectivas soluções propostas pelo autor. Primeiramente buscar-se-á tratar do problema que emerge do debate sobre que entidades podem ser consideradas reais, a saber, se e como entidades abstratas interagem com o mundo físico. Popper não aceita as posições monistas e dualistas porque ambas levam ao determinismo. Assim, para r...

  12. Karl Jaspers' phenomenology in the light of histological and X-ray metaphors.

    Science.gov (United States)

    Vlasova, Olga Alexandrovna; Beveridge, Allan

    2014-03-01

    The study considers the origins of Karl Jaspers' phenomenology. What did phenomenology mean to Jaspers and what was his personal perspective? What metaphors did he associate with it? This paper describes his phenomenological method by using the metaphors of histology and the X-ray. This perspective enables a better understanding, not only of the origins and essence of his phenomenology but also of its value for Jaspers himself. In Jaspers' daily life, he would have been familiar with microscopes and X-ray machines.

  13. A interpretação do Proslogion por Karl Barth

    Directory of Open Access Journals (Sweden)

    Paulo Ricardo Martines

    1996-12-01

    Full Text Available O objetivo principal deste texto é apresentai alguns elementos essenciais da interpretação do Proslogion feita por Karl Barth em seu livro S. Anselme, Fides Quaerens Intellectum. La preuve de l'existence de Dieu (trad. franc. Com Base no "programa teológico" de Anselmo, Barth identifica as linhas fundamentais para a leitura dos capítulos 2 a 4 do Pioslogion. Tentaremos mostrar a significação e o alcance dessa interpretação para a historiografia do pensamento anselmiano.

  14. Karl Gustaf Torsten Sjögren and Sjögren-Larsson syndrome

    OpenAIRE

    2011-01-01

    Karl Gustaf Torsten Sjögren (1896-1974) a Swedish psychiatrist and geneticist, was a pioneer of modern Swedish psychiatry. Sjögren studied medicine at the University of Uppsala. From 1932 to 1935, he was Head Physician and Director of Lillehagen Hospital in Gothenburg, and between 1935- 1945, he was physician-in-chief at the psychiatric department of Sahlgrenska Hospital in Gothenburg. Sjögren was professor of psychiatry at Karolinska Institutet from 1945 to 1961 and was elected to the Royal...

  15. Karl Barth’s role in church and politics from 1930 to 1935

    Directory of Open Access Journals (Sweden)

    André J. Groenewald

    2007-05-01

    Full Text Available Karl Barth saw in natural theology a threat to the church of Christ. He was convinced that the so-called “German Christians” under the influence of the National Socialist Party practised natural theology. He advocated the need for the church of Christ to be church according to the Word of God. The church can be true church of Christ when it listens to and obeys the true calling of God. Barth’s critique of an exclusive “Volkskirche” can serve as a corrective for the definition of the Nederduitsch Hervormde Kerk as a “volkskerk”.

  16. Karl Marx e a Essência Autogestionária da Comuna de Paris

    OpenAIRE

    Nildo Viana

    2011-01-01

    O artigo apresenta a interpretação da Comuna de Paris por Karl Marx como autogoverno dos produtores, autogestão social. Uma análise minuciosa do capítulo da obra “A Guerra Civil na França” fornece os elementos interpretativos para compreender a pe...

  17. Francisco de Paula Castro e Karl von den Steinen: expedicion?rios do Xingu (1884)

    OpenAIRE

    Ara?jo, Marcos Paulo Mendes

    2015-01-01

    No final do s?culo XIX, um significativo n?mero de pesquisadores estrangeiros esteve no Brasil a fim de realizar viagens explorat?rias. Um desses exploradores foi Karl von den Steinen que esteve no Brasil em duas oportunidades, sendo a primeira em 1884 quando visitou a regi?o do Xingu na companhia de outros dois alem?es, v?rios militares brasileiros e guias contratados. Esta pesquisa apresenta o resultado da leitura e an?lise do relat?rio de viagem produzido pelo capit?o de infantaria do Ex?r...

  18. Heterosexual Persons' Perceptions Regarding Language Use in Counseling: Extending Dorland and Fischer (2001)

    Science.gov (United States)

    Ross, Amanda D.; Waehler, Charles A.; Gray, Torie N.

    2013-01-01

    An important original study by Dorland and Fischer noted how the use of inclusive language can affect the therapeutic relationship positively for gay, lesbian, and bisexual clients. In this extension of that study with heterosexual participants ("N" = 179), there seemed to be low, but positive, salience of the language used by the…

  19. Osteochondroma of the tracheal wall in a Fischer's lovebird (Agapornis fischeri, Reichenow 1887).

    Science.gov (United States)

    Weissengruber, G; Loupal, G

    1999-01-01

    A Fischer's lovebird with dyspnea and stridorous breathing was examined by endoscopy. Tracheal stenosis was observed slightly cranial of the middle of the cervical segment. Histologically, an osteochondroma was identified as the cause of this stenosis. This is the first description of a tracheal osteochondroma in a bird.

  20. Manganese Promotion in Titania-Supported Cobalt Fischer-Tropsch Catalysis

    NARCIS (Netherlands)

    Morales Cano, F.

    2006-01-01

    Using the Fischer-Tropsch technology high molecular hydrocarbons are synthesized from CO/H2 mixtures through a surface-catalyzed polymerization reaction using Co-based catalysts. This process enables the transformation of natural gas into clean synthetic fuels. The work discribed in this thesis is t

  1. Modeling of single tube Fischer-Tropsch reactor for model biosyngas

    Energy Technology Data Exchange (ETDEWEB)

    Rafiq, Muhammad Hamid; Hustad, Johan Einar

    2010-07-01

    Fischer-Tropsch Synthesis is an important chemical process for the production of liquid fuels. The present study addresses the modeling of low temperature single tube Fischer- Tropsch reactor for a model biosyngas (33%H2, 17%CO and 50%N2). Cobalt based catalyst is used for synthesis due to its high activity and selectivity for linear hydrocarbons and lower price compared with other noble metals. The chemistry taking place in a FT reactor is complex but can be simplified by the following reaction (see original paper). For cobalt catalyst methanation reaction and shift reaction is neglected. Yates and Satterfield[1] determined the intrinsic rate constant of H2 consumption on a commercial cobalt catalyst. According to Steynberg et al.[2], the intrinsic activity of modern industrial cobalt catalyst is by a factor of three times higher then those reported by the above mentioned author. So, the equation of hydrogen consumption on a commercial cobalt catalyst is estimated (using the threefold value) and is given below: (see original paper). Modeling of Single tube fixed bed Fischer-Tropsch reactor is done with one or two dimensional pseudo homogeneous model. Among many thing the influence of cooling temperature effects are studied on the axial molar composition profiles, molar flow of reactant and product and reactant conversion. In addition effect of cooling temperature on the axial temperature profiles in a single tube Fischer-Tropsch reactor is also studied. (AG)

  2. On the Deactivation of Cobalt-based Fischer-Tropsch Catalysts

    NARCIS (Netherlands)

    Cats, K.H.

    2016-01-01

    The Fischer-Tropsch Synthesis (FTS) process is an attractive way to obtain synthetic liquid fuel from alternative energy sources such as natural gas, coal or biomass. However, the deactivation of the catalyst, consisting of cobalt nanoparticles supported on TiO2, currently hampers the industrial app

  3. A Highly Active and Selective Manganese Oxide Promoted Cobalt-on-Silica Fischer-Tropsch Catalyst

    NARCIS (Netherlands)

    den Breejen, Johan P.; Frey, Anne M.; Yang, Jia; Holmen, Anders; van Schooneveld, Matti M.; de Groot, Frank M. F.; Stephan, Odile; Bitter, Johannes H.; de Jong, Krijn P.

    2011-01-01

    A highly active and selective manganese oxide-promoted silica-supported cobalt catalyst for the Fischer-Tropsch reaction is reported. Co/MnO/SiO2 catalysts were prepared via impregnation of a cobalt nitrate and manganese nitrate precursor, followed by drying and calcination in an NO/He flow. The cat

  4. Structure-performance relationships for supported cobalt Fischer-Tropsch catalysts

    NARCIS (Netherlands)

    Eschemann, T.O.

    2015-01-01

    The Fischer-Tropsch synthesis (FTS) involves the heterogeneously catalyzed conversion of synthesis gas into water and hydrocarbons and offers a promising route for the synthesis of ultraclean fuels, chemicals and lubricants. The synthesis gas can be generated from different feedstocks, such as coal

  5. Cobalt supported on carbon nanofibers as catalysts for the Fischer-Tropsch synthesis

    NARCIS (Netherlands)

    Bezemer, G.L.

    2006-01-01

    The Fischer-Tropsch (FT) process converts synthesis gas (H2/CO) over a heterogeneous catalyst into hydrocarbons. Generally, cobalt catalysts supported on oxidic carriers are used for the FT process, however it appears to be difficult to obtain and maintain fully reduced cobalt particles. To overcome

  6. The psychology of thinking, animal psychology, and the young Karl Popper.

    Science.gov (United States)

    Ter Hark, Michel

    2004-01-01

    In the 1920s, Karl Popper wrote two large manuscripts on psychology that he never published. In his autobiography, Unended Quest, he attempts to reduce the importance of his work in psychology as much as possible, and in his philosophical work he is an antipsychologist. However, in this article, it is argued that Popper's early psychology has been pivotally important for the development of his philosophy. In particular, it is shown that Popper's views on psychology underwent a radical shift, one that paved the way for his characteristic deductive stance in philosophy. Popper's views shifted from an inductive and associationistic psychology toward a noninductive psychology of problem solving. Tracing the historical background of Popper's early work reveals how he integrated various parts of the psychology of Karl Groos into his analysis of the childish phenomenon of dogmatic thinking and how he shortly after appropriated various elements of the animal psychology of Hans Volkelt and Herbert Jennings in his biological approach to (dogmatic) thinking. In the monumental works of Otto Selz, however, Popper finally found the roots of a noninductive and biological approach to the growth of individual and scientific knowledge.

  7. Karl Popper’s model under the perspective of the applied social sciences

    Directory of Open Access Journals (Sweden)

    Milton de Abreu Campanario

    2012-04-01

    Full Text Available DOI: http://dx.doi.org/10.5007/2175-8077.2012v14n32p124Karl Popper is the leading philosopher of science in modern times, competing with Thomas Kuhn’s interpretation to the primacy of how to utilize de scientific method. Clearly, there are different versions for a reading of this important author who coined the method called deductive with test. This text recognizes the relevance of Karl Popper’s view of science as a practice in hard and biological fields, where it is widely accepted. However, this popularity is not shared in the applied social sciences area. This is an essay to rescue his contribution in an attempt to translate the concepts he developed in a didactic way. To this end, there will be an introduction to the fundamentals of science as specific form o knowledge, seeking to contrast the deductive and inductive approaches and procedures of what is known as formal science, basic and applied. An attempt to classify the formulation of theoretical propositions is undertaken with the use of different criteria, taking examples in the field of management and economics as an illustration.

  8. A crítica da epistemologia na sociologia do conhecimento de Karl Mannheim

    Directory of Open Access Journals (Sweden)

    Luís de Gusmão

    2011-04-01

    Full Text Available O artigo analisa a crítica da epistemologia normativa na obra de Karl Mannheim, sublinhando a sua presença tanto na fase mais filosófica, associada ao elogio do historicismo, como na Sociologia do Conhecimento posterior. Chama a atenção também para a atualidade dessa crítica: ao censurar os epistemólogos do seu tempo por não levarem na devida conta os achados das ciências empíricas particulares, Mannheim antecipa, em décadas, tendências mais recentes da Sociologia do Conhecimento e da reflexão epistemológica.The article analyzes the critique of normative epistemology in the work of Karl Mannheim, stressing its presence both in his more philosophical phase, associated with the praise of historicism, and in his later Sociology of Knowledge. It also calls attention to the relevance of this critique: attacking the epistemologists of his time by not taking into proper account the findings of particular empirical sciences, Mannheim anticipated by decades recent trends in the Sociology of Knowledge and epistemological reflection.

  9. La memoria, el tiempo y la historia en Karl Mannheim y en Maurice Halbwachs

    Directory of Open Access Journals (Sweden)

    Gérard NAMER

    2009-03-01

    Full Text Available RESUMEN: Las aportaciones de Maurice Halbwachs sobre la sociología de la memoria son suficientemente conocidas. Los análisis de Karl Mannheim añaden nuevos enfoques a los estudios sobre la sociología de la memoria y sus conceptos. Este artículo trata de comparar las aportaciones sociológicas de ambos, y cómo ellos renuevan, uno y otro sin conocerse, la concepción del tiempo, de la memoria y de la historia.ABSTRACT: The contributions of Maurice Halbwachs in regard to the sociology of memory are sufficiently well known. The analyses of Karl Mannheim add new approaches to the studies on the sociology of memory and its concepts. The objective of this article is to compare the sociological contributions of both to the study of memory in the period between the wars. Keywords: Sociology of knowledge, sociology of memory, individual memory, collective memory, social frameworks of memory, diverse memories, time, diverse social times, history, cultural history, conservative thought, totalitarianism.

  10. Characterization of Sea Lettuce Surface Functional Groups by Potentiometric Titrations

    Science.gov (United States)

    Ebling, A. M.; Schijf, J.

    2008-12-01

    In pursuit of our ultimate goal to better understand the prodigious capacity of the marine macroalga Ulva lactuca (sea lettuce) for adsorbing a broad range of dissolved trace metals from seawater, we performed an initial characterization of its surface functional groups. Specifically, the number of distinct functional groups as well as their individual bulk concentrations and acid dissociation constants (pKas) were determined by potentiometric titrations in NaCl solutions of various ionic strengths (I = 0.01-5.0 M), under inert nitrogen atmosphere at 25°C. Depending on the ionic strength, Ulva samples were manually titrated down to pH 2 or 3 with 1 N HCl and then up to pH 10 with 1 N NaOH in steps of 0.1-0.2 units, continuously monitoring pH with a glass combination electrode. Titrations of a dehydrated Ulva standard reference material (BCR-279) were compared with fresh Ulva tissue cultured in our laboratory. A titration in filtered natural seawater was also compared with one in an NaCl solution of equal ionic strength. Equilibrium constants for the ionization of water in NaCl solutions as a function of ionic strength were obtained from the literature. Fits to the titration data ([H]T vs. pH) were performed with the FITEQL4.0 computer code using non-electrostatic 3-, 4-, and 5-site models, either by fixing ionic strength at its experimental value or by allowing it to be extrapolated to zero, while considering all functional group pKas and bulk concentrations as adjustable parameters. Since pKas and bulk concentrations were found to be strongly correlated, the latter were also fixed in some cases to further constrain the pKas. Whereas these calculations are currently ongoing, preliminary results point to three, possibly four, functional groups with pKas of about 4.1, 6.3, and 9.5 at I = 0. Bulk concentrations of the three groups are very similar, about 5-6×10-4 mol/g based on dry weight, which suggests that all are homogeneously distributed over the surface and

  11. Shakespearean Thoughts as Statutes. Law and Literature in Karl Kraus Pensieri shakespeariani come leggi dello stato. Letteratura e diritto in Karl Kraus

    Directory of Open Access Journals (Sweden)

    Irene Fantappie

    2012-04-01

    Full Text Available It is not possible to understand Karl Kraus, claims Walter Benjamin, without assuming that in the oeuvre of the Viennese writer "everything takes place in the sphere of law". In Kraus’s thought legal issues are strongly related to literature and language. His concept of law stems from a higher ideal of ‘justice’; justice is based on language and language has a strong ideal and prescriptive value. Through the use of quotation Kraus charges literature and journalism with betraying language, while on the other hand he charges law with betraying justice. This essay aims at demonstrating trough an interdisciplinary approach that Kraus did not only involve law issues in his literary writings, he also invested some literary works – especially Shakespeare’s plays – with a legal value. In Kraus’s thought Shakespeare is a symbol of consubstantiality between reality and literature, and an 'encyclopedia' providing eternally valid categories. As an ideal paradigm for the interpretation of reality, Shakespeare is the utopian background of Kraus’s reflection on language and justice, bearing witness to the indissolubility, in Kraus’s thought, of literature and law.   È impossibile comprendere alcunché di Karl Kraus, afferma Walter Benjamin, se non si capisce che nell’opera del grande scrittore viennese «tutto ha luogo nella sfera del diritto». In Kraus l’analisi delle questioni giuridiche è inscindibile dalla riflessione sulla letteratura e sul linguaggio. La disamina del diritto muove da un più alto ideale di giustizia fondato sulla lingua, e specularmente il linguaggio possiede una forte valenza ideale e prescrittivo-normativa. Attraverso l’uso della citazione Kraus mette sotto accusa letteratura e giornalismo in nome di un più alto ideale di lingua, mentre nei suoi scritti letterari mette sotto accusa il sistema del diritto in nome di un più alto ideale di giustizia. Scopo del presente saggio è dimostrare, utilizzando un

  12. A titration model for evaluating calcium hydroxide removal techniques

    Directory of Open Access Journals (Sweden)

    Mark PHILLIPS

    2015-02-01

    Full Text Available Objective Calcium hydroxide (Ca(OH2 has been used in endodontics as an intracanal medicament due to its antimicrobial effects and its ability to inactivate bacterial endotoxin. The inability to totally remove this intracanal medicament from the root canal system, however, may interfere with the setting of eugenol-based sealers or inhibit bonding of resin to dentin, thus presenting clinical challenges with endodontic treatment. This study used a chemical titration method to measure residual Ca(OH2 left after different endodontic irrigation methods. Material and Methods Eighty-six human canine roots were prepared for obturation. Thirty teeth were filled with known but different amounts of Ca(OH2 for 7 days, which were dissolved out and titrated to quantitate the residual Ca(OH2 recovered from each root to produce a standard curve. Forty-eight of the remaining teeth were filled with equal amounts of Ca(OH2 followed by gross Ca(OH2 removal using hand files and randomized treatment of either: 1 Syringe irrigation; 2 Syringe irrigation with use of an apical file; 3 Syringe irrigation with added 30 s of passive ultrasonic irrigation (PUI, or 4 Syringe irrigation with apical file and PUI (n=12/group. Residual Ca(OH2 was dissolved with glycerin and titrated to measure residual Ca(OH2 left in the root. Results No method completely removed all residual Ca(OH2. The addition of 30 s PUI with or without apical file use removed Ca(OH2 significantly better than irrigation alone. Conclusions This technique allowed quantification of residual Ca(OH2. The use of PUI (with or without apical file resulted in significantly lower Ca(OH2 residue compared to irrigation alone.

  13. Titratable acidity of beverages influences salivary pH recovery

    Directory of Open Access Journals (Sweden)

    Livia Maria Andaló TENUTA

    2015-01-01

    Full Text Available A low pH and a high titratable acidity of juices and cola-based beverages are relevant factors that contribute to dental erosion, but the relative importance of these properties to maintain salivary pH at demineralizing levels for long periods of time after drinking is unknown. In this crossover study conducted in vivo, orange juice, a cola-based soft drink, and a 10% sucrose solution (negative control were tested. These drinks differ in terms of their pH (3.5 ± 0.04, 2.5 ± 0.05, and 5.9 ± 0.1, respectively and titratable acidity (3.17 ± 0.06, 0.57 ± 0.04 and < 0.005 mmols OH- to reach pH 5.5, respectively. Eight volunteers with a normal salivary flow rate and buffering capacity kept 15 mL of each beverage in their mouth for 10 s, expectorated it, and their saliva was collected after 15, 30, 45, 60, 90, and 120 s. The salivary pH, determined using a mini pH electrode, returned to the baseline value at 30 s after expectoration of the cola-based soft drink, but only at 90 s after expectoration of the orange juice. The salivary pH increased to greater than 5.5 at 15 s after expectoration of the cola drink and at 30 s after expectoration of the orange juice. These findings suggest that the titratable acidity of a beverage influences salivary pH values after drinking acidic beverages more than the beverage pH.

  14. Titratable acidity of beverages influences salivary pH recovery.

    Science.gov (United States)

    Tenuta, Livia Maria Andaló; Fernández, Constanza Estefany; Brandão, Ana Carolina Siqueira; Cury, Jaime Aparecido

    2015-01-01

    A low pH and a high titratable acidity of juices and cola-based beverages are relevant factors that contribute to dental erosion, but the relative importance of these properties to maintain salivary pH at demineralizing levels for long periods of time after drinking is unknown. In this crossover study conducted in vivo, orange juice, a cola-based soft drink, and a 10% sucrose solution (negative control) were tested. These drinks differ in terms of their pH (3.5 ± 0.04, 2.5 ± 0.05, and 5.9 ± 0.1, respectively) and titratable acidity (3.17 ± 0.06, 0.57 ± 0.04 and pH 5.5, respectively). Eight volunteers with a normal salivary flow rate and buffering capacity kept 15 mL of each beverage in their mouth for 10 s, expectorated it, and their saliva was collected after 15, 30, 45, 60, 90, and 120 s. The salivary pH, determined using a mini pH electrode, returned to the baseline value at 30 s after expectoration of the cola-based soft drink, but only at 90 s after expectoration of the orange juice. The salivary pH increased to greater than 5.5 at 15 s after expectoration of the cola drink and at 30 s after expectoration of the orange juice. These findings suggest that the titratable acidity of a beverage influences salivary pH values after drinking acidic beverages more than the beverage pH.

  15. Monitoring assembly of ribonucleoprotein complexes by isothermal titration calorimetry

    Science.gov (United States)

    Recht, Michael I.; Ryder, Sean P.; Williamson, James R.

    2010-01-01

    Isothermal titration calorimetry (ITC) is a useful technique to study RNA-protein interactions, as it provides the only method by which the thermodynamic parameters of free energy, enthalpy, and entropy can be directly determined. This chapter presents a general procedure for studying RNA-protein interactions using ITC, and gives specific examples for monitoring the binding of Caenorhabditis elegans GLD-1 STAR domain to TGE RNA and the binding of Aquifex aeolicus S6:S18 ribosomal protein heterodimer to an S15-rRNA complex. PMID:18982287

  16. Isothermal Titration Calorimetry: Assisted Crystallization of RNA-Ligand Complexes.

    Science.gov (United States)

    Da Veiga, Cyrielle; Mezher, Joelle; Dumas, Philippe; Ennifar, Eric

    2016-01-01

    The success rate of nucleic acids/ligands co-crystallization can be significantly improved by performing preliminary biophysical analyses. Among suitable biophysical approaches, isothermal titration calorimetry (ITC) is certainly a method of choice. ITC can be used in a wide range of experimental conditions to monitor in real time the formation of the RNA- or DNA-ligand complex, with the advantage of providing in addition the complete binding profile of the interaction. Following the ITC experiment, the complex is ready to be concentrated for crystallization trials. This chapter describes a detailed experimental protocol for using ITC as a tool for monitoring RNA/small molecule binding, followed by co-crystallization.

  17. Isothermal Titration Calorimetry of Membrane Proteins – Progress and Challenges

    Science.gov (United States)

    Rajarathnam, Krishna; Rösgen, Jörg

    2013-01-01

    Summary Integral membrane proteins, including G protein-coupled receptors (GPCR) and ion channels, mediate diverse biological functions that are crucial to all aspects of life. The knowledge of the molecular mechanisms, and in particular, the thermodynamic basis of the binding interactions of the extracellular ligands and intracellular effector proteins is essential to understand the workings of these remarkable nanomachines. In this review, we describe how isothermal titration calorimetry (ITC) can be effectively used to gain valuable insights into the thermodynamic signatures (enthalpy, entropy, affinity, and stoichiometry), which would be most useful for drug discovery studies, considering that more than 30% of the current drugs target membrane proteins. PMID:23747362

  18. Characterization of Native and Modified Starches by Potentiometric Titration

    Directory of Open Access Journals (Sweden)

    Diana Soto

    2014-01-01

    Full Text Available The use of potentiometric titration for the analysis and characterization of native and modified starches is highlighted. The polyelectrolytic behavior of oxidized starches (thermal and thermal-chemical oxidation, a graft copolymer of itaconic acid (IA onto starch, and starch esters (mono- and diester itaconate was compared with the behavior of native starch, the homopolymer, and the acid employed as a graft monomer and substituent. Starch esters showed higher percentages of acidity, followed by graft copolymer of itaconic acid and finally oxidized starches. Analytical techniques and synthesis of modified starches were also described.

  19. CHAIN-LIMITING OPERATION OF FISCHER-TROPSCH REACTOR

    Energy Technology Data Exchange (ETDEWEB)

    Apostolos A. Nikolopoulos; Santosh K. Gangwal

    2003-06-01

    The use of pulsing in Fischer-Tropsch (FT) synthesis to limit the hydrocarbon chain growth and maximize the yield of diesel-range (C{sub 10}-C{sub 20}) products was examined on high-chain-growth-probability ({alpha} {ge} 0.9) FT catalysts. Pulsing experiments were conducted using a stainless-steel fixed-bed micro-reactor, equipped with both on-line (for the permanent gases and light hydrocarbons, C{sub 1}-C{sub 15}) and off-line (for the heavier hydrocarbons, C{sub 10}-C{sub 65}) gas chromatography analysis. Additional experiments were performed using a highly active attrition-resistant iron-based FT synthesis catalyst in a 1-liter continuous stirred-tank rector (CSTR). On both a Co-ZrO{sub 2}/SiO{sub 2} and a Co/Al{sub 2}O{sub 3} FT synthesis catalyst application of H{sub 2} pulsing causes significant increase in CO conversion, and only an instantaneous increase in undesirable selectivity to CH{sub 4}. Increasing the frequency of H{sub 2} pulsing enhances the selectivity to C{sub 10}-C{sub 20} compounds but the chain-growth probability {alpha} remains essentially unaffected. Increasing the duration of H{sub 2} pulsing results in enhancing the maximum obtained CO conversion and an instantaneous selectivity to CH{sub 4}. An optimum set of H{sub 2} pulse parameters (pulse frequency, pulse duration) is required for maximizing the yield of desirable diesel-range C{sub 10}-C{sub 20} products. Application of a suitable H{sub 2} pulse in the presence of added steam in the feed is a simple method to overcome the loss in activity and the shift in paraffin vs. olefin selectivity (increase in the olefin/paraffin ratio) caused by the excess steam. A decrease in syngas concentration has a strong suppressing effect on the olefin/paraffin ratio of the light hydrocarbon products. Higher syngas concentration can increase the chain growth probability {alpha} and thus allow for better evaluation of the effect of pulsing on FT synthesis. On a high-{alpha} Fe/K/Cu/SiO{sub 2} FT

  20. Kinetics of Slurry Phase Fischer-Tropsch Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Dragomir B. Bukur; Gilbert F. Froment; Tomasz Olewski; Lech Nowicki; Madhav Nayapati

    2006-12-31

    The overall objective of this project is to develop a comprehensive kinetic model for slurry-phase Fischer-Tropsch synthesis (FTS) employing iron-based catalysts. This model will be validated with experimental data obtained in a stirred-tank slurry reactor (STSR) over a wide range of process conditions. Three STSR tests of the Ruhrchemie LP 33/81 catalyst were conducted to collect data on catalyst activity and selectivity under 25 different sets of process conditions. The observed decrease in 1-olefin content and increase in 2-olefin and n-paraffin contents with the increase in conversion are consistent with a concept that 1-olefins participate in secondary reactions (e.g. 1-olefin hydrogenation, isomerization and readsorption), whereas 2-olefins and n-paraffins are formed in these reactions. Carbon number product distribution showed an increase in chain growth probability with increase in chain length. Vapor-liquid equilibrium calculations were made to check validity of the assumption that the gas and liquid phases are in equilibrium during FTS in the STSR. Calculated vapor phase compositions were in excellent agreement with experimental values from the STSR under reaction conditions. Discrepancies between the calculated and experimental values for the liquid-phase composition (for some of the experimental data) are ascribed to experimental errors in the amount of wax collected from the reactor, and the relative amounts of hydrocarbon wax and Durasyn 164 oil (start-up fluid) in the liquid samples. Kinetic parameters of four kinetic models (Lox and Froment, 1993b; Yang et al., 2003; Van der Laan and Beenackers, 1998, 1999; and an extended kinetic model of Van der Laan and Beenackers) were estimated from experimental data in the STSR tests. Two of these kinetic models (Lox and Froment, 1993b; Yang et al., 2003) can predict a complete product distribution (inorganic species and hydrocarbons), whereas the kinetic model of Van der Laan and Beenackers (1998, 1999) can

  1. Isothermal titration calorimetry: general formalism using binding polynomials.

    Science.gov (United States)

    Freire, Ernesto; Schön, Arne; Velazquez-Campoy, Adrian

    2009-01-01

    The theory of the binding polynomial constitutes a very powerful formalism by which many experimental biological systems involving ligand binding can be analyzed under a unified framework. The analysis of isothermal titration calorimetry (ITC) data for systems possessing more than one binding site has been cumbersome because it required the user to develop a binding model to fit the data. Furthermore, in many instances, different binding models give rise to identical binding isotherms, making it impossible to discriminate binding mechanisms using binding data alone. One of the main advantages of the binding polynomials is that experimental data can be analyzed by employing a general model-free methodology that provides essential information about the system behavior (e.g., whether there exists binding cooperativity, whether the cooperativity is positive or negative, and the magnitude of the cooperative energy). Data analysis utilizing binding polynomials yields a set of binding association constants and enthalpy values that conserve their validity after the correct model has been determined. In fact, once the correct model is validated, the binding polynomial parameters can be immediately translated into the model specific constants. In this chapter, we describe the general binding polynomial formalism and provide specific theoretical and experimental examples of its application to isothermal titration calorimetry.

  2. Measuring the Kinetics of Molecular Association by Isothermal Titration Calorimetry.

    Science.gov (United States)

    Vander Meulen, Kirk A; Horowitz, Scott; Trievel, Raymond C; Butcher, Samuel E

    2016-01-01

    The real-time power response inherent in an isothermal titration calorimetry (ITC) experiment provides an opportunity to directly analyze association kinetics, which, together with the conventional measurement of thermodynamic quantities, can provide an incredibly rich description of molecular binding in a single experiment. Here, we detail our application of this method, in which interactions occurring with relaxation times ranging from slightly below the instrument response time constant (12.5 s in this case) to as large as 600 s can be fully detailed in terms of both the thermodynamics and kinetics. In a binding titration scenario, in the most general case an injection can reveal an association rate constant (kon). Under more restrictive conditions, the instrument time constant-corrected power decay following each injection is simply an exponential decay described by a composite rate constant (kobs), from which both kon and the dissociation rate constant (koff) can be extracted. The data also support the viability of this exponential approach, for kon only, for a slightly larger set of conditions. Using a bimolecular RNA folding model and a protein-ligand interaction, we demonstrate and have internally validated this approach to experiment design, data processing, and error analysis. An updated guide to thermodynamic and kinetic regimes accessible by ITC is provided.

  3. Semi-automated potentiometric titration method for uranium characterization

    Energy Technology Data Exchange (ETDEWEB)

    Cristiano, B.F.G., E-mail: barbara@ird.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Instituto de Radioprotecao e Dosimetria (IRD), Avenida Salvador Allende s/n Recreio dos Bandeirantes, PO Box 37750, Rio de Janeiro, 22780-160 RJ (Brazil); Delgado, J.U.; Silva, J.W.S. da; Barros, P.D. de; Araujo, R.M.S. de [Comissao Nacional de Energia Nuclear (CNEN), Instituto de Radioprotecao e Dosimetria (IRD), Avenida Salvador Allende s/n Recreio dos Bandeirantes, PO Box 37750, Rio de Janeiro, 22780-160 RJ (Brazil); Lopes, R.T. [Programa de Engenharia Nuclear (PEN/COPPE), Universidade Federal do Rio de Janeiro (UFRJ), Ilha do Fundao, PO Box 68509, Rio de Janeiro, 21945-970 RJ (Brazil)

    2012-07-15

    The manual version of the potentiometric titration method has been used for certification and characterization of uranium compounds. In order to reduce the analysis time and the influence of the analyst, a semi-automatic version of the method was developed in the Brazilian Nuclear Energy Commission. The method was applied with traceability assured by using a potassium dichromate primary standard. The combined standard uncertainty in determining the total concentration of uranium was around 0.01%, which is suitable for uranium characterization. - Highlights: Black-Right-Pointing-Pointer We developed a semi-automatic version of potentiometric titration method. Black-Right-Pointing-Pointer The method is used for certification and characterization of uranium compounds. Black-Right-Pointing-Pointer The traceability of the method was assured by a K{sub 2}Cr{sub 2}O{sub 7} primary standard. Black-Right-Pointing-Pointer The results of U{sub 3}O{sub 8} reference material analyzed was consistent with certified value. Black-Right-Pointing-Pointer The uncertainty obtained, near 0.01%, is useful for characterization purposes.

  4. Measuring Multivalent Binding Interactions by Isothermal Titration Calorimetry.

    Science.gov (United States)

    Dam, Tarun K; Talaga, Melanie L; Fan, Ni; Brewer, Curtis F

    2016-01-01

    Multivalent glycoconjugate-protein interactions are central to many important biological processes. Isothermal titration calorimetry (ITC) can potentially reveal the molecular and thermodynamic basis of such interactions. However, calorimetric investigation of multivalency is challenging. Binding of multivalent glycoconjugates to proteins (lectins) often leads to a stoichiometry-dependent precipitation process due to noncovalent cross-linking between the reactants. Precipitation during ITC titration severely affects the quality of the baseline as well as the signals. Hence, the resulting thermodynamic data are not dependable. We have made some modifications to address this problem and successfully studied multivalent glycoconjugate binding to lectins. We have also modified the Hill plot equation to analyze high quality ITC raw data obtained from multivalent binding. As described in this chapter, ITC-driven thermodynamic parameters and Hill plot analysis of ITC raw data can provide valuable information about the molecular mechanism of multivalent lectin-glycoconjugate interactions. The methods described herein revealed (i) the importance of functional valence of multivalent glycoconjugates, (ii) that favorable entropic effects contribute to the enhanced affinities associated with multivalent binding, (iii) that with the progression of lectin binding, the microscopic affinities of the glycan epitopes of a multivalent glycoconjugate decrease (negative cooperativity), (iv) that lectin binding to multivalent glycoconjugates, especially to mucins, involves internal diffusion jumps, (bind and jump) and (v) that scaffolds of glycoconjugates influence their entropy of binding. © 2016 Elsevier Inc. All rights reserved.

  5. Characterization of protein-protein interactions by isothermal titration calorimetry.

    Science.gov (United States)

    Velazquez-Campoy, Adrian; Leavitt, Stephanie A; Freire, Ernesto

    2015-01-01

    The analysis of protein-protein interactions has attracted the attention of many researchers from both a fundamental point of view and a practical point of view. From a fundamental point of view, the development of an understanding of the signaling events triggered by the interaction of two or more proteins provides key information to elucidate the functioning of many cell processes. From a practical point of view, understanding protein-protein interactions at a quantitative level provides the foundation for the development of antagonists or agonists of those interactions. Isothermal Titration Calorimetry (ITC) is the only technique with the capability of measuring not only binding affinity but the enthalpic and entropic components that define affinity. Over the years, isothermal titration calorimeters have evolved in sensitivity and accuracy. Today, TA Instruments and MicroCal market instruments with the performance required to evaluate protein-protein interactions. In this methods paper, we describe general procedures to analyze heterodimeric (porcine pancreatic trypsin binding to soybean trypsin inhibitor) and homodimeric (bovine pancreatic α-chymotrypsin) protein associations by ITC.

  6. Outpatient titration of carbidopa/levodopa enteral suspension (Duopa).

    Science.gov (United States)

    Pahwa, Rajesh; Lyons, Kelly E

    2017-05-01

    Carbidopa/levodopa enteral suspension (CLES; Duopa) is a suspension or gel formulation of carbidopa/levodopa that is approved by the USA Food and Drug Administration for the treatment of advanced Parkinson's disease patients with motor fluctuations. CLES is delivered at a constant rate continuously throughout the day into the jejunum through an infusion pump via a PEG-J tube implanted surgically. The efficacy of CLES was established in the USA based on a randomized, double-blind, double-dummy, active controlled, parallel group and 12-week study, in which mean daily OFF time was reduced by 4.0 h, compared to 1.9 h with oral immediate release carbidopa/levodopa. The CLES hardware consists of a cassette containing the drug, a pump to deliver the drug and tubing to connect the PEG-J to the pump. It is critical to understand the appropriate conversion of the carbidopa/levodopa daily dosages to the CLES dosage and how to program the pump and titrate CLES to achieve the most effective dose. We describe one methodology for patient selection, outpatient titration and pump programming.

  7. Mida kujutab endast IB õppekava? / Toomas Kruusimägi, Anu Parts, Karl Hendrik Thomson ; intervjueerinud Raivo Juurak

    Index Scriptorium Estoniae

    Kruusimägi, Toomas, 1962-

    2010-01-01

    Uuest rahvusvahelisest International Baccalaureate'i (IB) õppekavast ja selle rakendamisest Tallinna Inglise Kolledži 11. klassis alates möödunud aastast räägivad kooli direktor Toomas Kruusimägi, õppedirektor Anu Parts ning õpilane Karl Hendrik Thomson

  8. Naised käsu korras firmade juhatusse! Jah või ei? / Kairi Alt, Aveli Kippari, Karl Koort... [jt.

    Index Scriptorium Estoniae

    2011-01-01

    Küsimusele vastavad Columbus IT Partner Eesti AS personalijuht Kairi Alt, Stele ja Riveli omanik Aveli Kippari, AS Panaviatic'i turundusjuht Karl Koort, OÜ Tarkvara Tehnoloogia Arenduskeskuse tegevjuht Indrek Vainu, AS PricewaterhouseCoopers auditiosakonna direktor Eva Jansen, Kalev Chocolate Factory tootmisjuht Hardo Reinike

  9. Blank ja Jeron (sero.org) / Joachim Blank, Karl Heinz Jeron ; interv. Tilman Baumgärtel

    Index Scriptorium Estoniae

    Blank, Joachim

    2006-01-01

    Nime sero.org all esinenud saksa kunstnikepaarist Joachim Blankist (sünd. 1963) ja Karl Heinz Jeronist ning nende loomingust, intervjuu kunstnikega nende Berliini ateljees 10. II 2000. Saksa võrgukunsti edendamisest rühmituste Lux Logis, Handshake ja Internationale Stadt koosseisus, jututubadest, teostest "Dump your trash", "Re-M@il", installatsioonidest "re: represent", "Scanner +++", "sign.post" ja muust

  10. Blank ja Jeron (sero.org) / Joachim Blank, Karl Heinz Jeron ; interv. Tilman Baumgärtel

    Index Scriptorium Estoniae

    Blank, Joachim

    2006-01-01

    Nime sero.org all esinenud saksa kunstnikepaarist Joachim Blankist (sünd. 1963) ja Karl Heinz Jeronist ning nende loomingust, intervjuu kunstnikega nende Berliini ateljees 10. II 2000. Saksa võrgukunsti edendamisest rühmituste Lux Logis, Handshake ja Internationale Stadt koosseisus, jututubadest, teostest "Dump your trash", "Re-M@il", installatsioonidest "re: represent", "Scanner +++", "sign.post" ja muust

  11. Mapping a Space of Biography: Karl Triebold and the Waldschule of Senne I-Bielefeld (c.1923-1939)

    Science.gov (United States)

    Thyssen, Geert

    2012-01-01

    Starting from a "life geography" of Karl Triebold, a leading figure in open-air education, this article provides an understanding of the seemingly ordinary but still idiosyncratic development of a German open-air school. Triebold's life's work, the fight against tuberculosis, conceived as character education through healthy occupation,…

  12. Naised käsu korras firmade juhatusse! Jah või ei? / Kairi Alt, Aveli Kippari, Karl Koort... [jt.

    Index Scriptorium Estoniae

    2011-01-01

    Küsimusele vastavad Columbus IT Partner Eesti AS personalijuht Kairi Alt, Stele ja Riveli omanik Aveli Kippari, AS Panaviatic'i turundusjuht Karl Koort, OÜ Tarkvara Tehnoloogia Arenduskeskuse tegevjuht Indrek Vainu, AS PricewaterhouseCoopers auditiosakonna direktor Eva Jansen, Kalev Chocolate Factory tootmisjuht Hardo Reinike

  13. Saksa välisminister : kirjutage, et Joschka Fischer on süüdi / Heiki Suurkask

    Index Scriptorium Estoniae

    Suurkask, Heiki, 1972-

    2005-01-01

    Saksa välisminister Joschka Fischer tunnistas oma poliitilist vastutust selle eest, et Saksamaa viisaga oli võimalik illegaalseid immigrante Saksamaale tuua, samas süüdistas ta opositsiooni skandaali ülespuhumises

  14. Signal processing with a summing operational amplifier in multicomponent potentiometric titrations.

    Science.gov (United States)

    Parczewski, A

    1987-06-01

    It has been proved that application of two indicator electrodes connected to the ordinary titration apparatus through an auxiliary electronic device (a summing operational amplifier) significantly extends the scope of multicomponent potentiometric titrations in which the analytes are determined simultaneously from a single titration curve. For each analyte there is a corresponding potential jump on the titration curve. By application of the proposed auxiliary device, the sum of the electrode potentials is measured. The device also enables the relative sizes of the potential jumps at the end-points on the titration curve to be varied. The advantages of the proposed signal processing are exemplified by complexometric potentiometric titrations of Fe(III) and Cu(II) in mixtures, with a platinum electrode and a copper ion-selective electrode as the indicator electrodes.

  15. Potential estimation of titratable acidity in cow milk using mid-infrared spectrometry

    OpenAIRE

    Colinet, Frédéric; Soyeurt, Hélène; Anceau, Christine; Vanlierde, Amélie; Keyen, Nicolas; Pierre DARDENNE; Gengler, Nicolas; Sindic, Marianne

    2010-01-01

    Milk coagulation has a direct effect on cheese yield. Several factors influence the milk coagulation kinetics. In addition to calcium and milk protein concentrations, titratable acidity influences all the phases of milk coagulation. The objective of this research was to study the feasibility of prediction of titratable acidity directly in bovine milk using mid-infrared spectrometry. In order to maximize the variability in the measurements of titratable acidity, milk samples were collected on ...

  16. Effect of potassium promoter on cobalt nano-catalysts for fischer-tropsch reaction

    Science.gov (United States)

    Ali, Sardar; Mohd Zabidi, Noor Asmawati; Subbarao, Duvvuri

    2012-09-01

    In the present work effect of potassium on cobalt nano-catalysts for Fischer-Tropsch reaction has been presented. The catalysts were prepared using a wet impregnation method and promoted with potassium. Samples were characterized by nitrogen adsorption, H2-TPR, and TEM. The Fischer-Tropsch Synthesis (FTS) was carried out in a fixed-bed microreactor 220 δC, 1 atm, H2/CO = 2 and a velocity (SV) =12 L/g.h. for 5 h. Addition of potassium into Co/CNTs decreased the average size of cobalt nanoparticles and the catalyst reducibility. Potassium-promoted Co catalyst resulted in appreciable increase in the selectivity of C5+ hydrocarbons and suppressed methane formation. The 0.06%KCo/CNTs catalyst enhanced the C5+ hydrocarbons selectivity by a factor of 23.5% and reduced the methane selectivity by a factor of 39.6%

  17. Modeling of a slurry bubble column reactor for Fischer-Tropsch synthesis

    Institute of Scientific and Technical Information of China (English)

    QIAN Wei-xin; MA Hong-fang; LI Tao; YING Wei-yong; FANG Ding-ye

    2012-01-01

    On the basis of the global CO consumption rate model,the lumped product distribution model and the sedimentation-dispersion model of a catalyst,a steady-state,one-dimensional mathematical model of the slurry bubble column reactor for Fischer-Tropsch synthesis were established.The mathematical simulation of the slurry bubble column reactor for Fischer-Tropsch synthesis was carried out under the following typical industrial operating conditions:temperature 230 ℃,pressure 3.0 MPa,gas flow 5× 105 m3/h,catalyst content in slurry phase 30%,reactor diameter 5.0 m and the composition of feed gas:y(H2)=0.60,y(CO)=0.30,y(N2)=0.10.The influences of operating pressure,temperature and m(H2)/m(CO) in feed gas on the reactor's reaction performance were simulated.

  18. Nitrogen isotope fractionations in the Fischer-Tropsch synthesis and in the Miller-Urey reaction

    Science.gov (United States)

    King, C.-C.; Clayton, R. N.; Hayatsu, R.; Studier, M. H.

    1979-01-01

    Nitrogen isotope fractionations have been measured in Fischer-Tropsch and Miller-Urey reactions in order to determine whether these processes can account for the large N-15/N-14 ratios found in organic matter in carbonaceous chondrites. Polymeric material formed in the Fischer-Tropsch reaction was enriched in N-15 by only 3 per mil relative to the starting material (NH3). The N-15 enrichment in polymers from the Miller-Urey reaction was 10-12 per mil. Both of these fractionations are small compared to the 80-90 per mil differences observed between enstatite chondrites and carbonaceous chondrites. These large differences are apparently due to temporal or spatial variations in the isotopic composition of nitrogen in the solar nebula, rather than to fractionation during the production of organic compounds.

  19. Design of generic coal conversion facilities: Indirect coal liquefaction, Fischer-Tropsch synthesis

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    A comprehensive review of Fischer-Tropsch (F-T) technology, including fixed, fluidized, and bubble column reactors, was undertaken in order to develop an information base before initiating the design of the Fischer-Tropsch indirect liquefaction PDU as a part of the Generic Coal Conversion Facilities to be built at the Pittsburgh Energy Technology Center (PETC). The pilot plant will include a fixed bed and slurry bubble column reactor for the F-T mode of operation. The review encompasses current status of both these technologies, their key variables, catalyst development, future directions, and potential improvement areas. However, more emphasis has been placed on the slurry bubble column reactor since this route is likely to be the preferred technology for commercialization, offering process advantages and, therefore, better economics than fixed and fluidized bed approaches.

  20. El huracán Karl: concepciones sobre su origen en una comunidad de Veracruz

    Directory of Open Access Journals (Sweden)

    Arturo Marinero Heredia

    2015-01-01

    Full Text Available Se analizan las concepciones e ideas de pobladores adultos sobre las afectaciones sufridas por el huracán Karl en 2010, en el municipio de La Antigua, Veracruz. Los datos se obtuvieron de entrevistas a informantes claves y grupos focales, además de la revisión de notas periodísticas. Se observa que las concepciones e ideas sobre el origen del desastre las adjudican a las fuerzas naturales, espirituales o religiosas sin reconocer la responsabilidad de las autoridades encargadas de elaborar políticas públicas en la materia y en la falta de previsión social y personal frente a sus devastadores efectos. Esta concepción dificulta la prevención, mantiene a la comunidad en situación de vulnerabilidad e impide o imposibilita la integración, la cohesión social y la acción colectiva.

  1. Cybernetics and Social Order. Models and Images of Society in Norbert Wiener and Karl Deutsch

    Directory of Open Access Journals (Sweden)

    Roberto Carradore

    2013-07-01

    Full Text Available The present contribution aims at defining the relation between cybernetics and social theory from the perspective of society as order. After an historical framework of the cybernetic movement, a careful reading of the works of Norbert Wiener, in which he introduced the concept of feed-back and the idea of information society, has revealed a keen awareness about the social effects of technological innovation. Among the social scientists who had made use of cybernetic concepts, it has been considered the work of Karl Deutsch, which was one of the first completely cybernetic perspective for the study of political and social phenomena. The main conclusion is that cybernetics, as a meeting point between different disciplines, has produced an image of self-regulated society in line with the image of society as order.

  2. Rationalism and traditionalism in politics. The correspondence between Karl R. Popper and Michael Oakeshott

    Directory of Open Access Journals (Sweden)

    Spartaco Pupo

    2016-07-01

    Full Text Available The correspondence of 1948 between Karl Popper and Michael Oakeshott, translated for the first time in Italian and published in the appendix to this paper, demonstrates the existence of two different ways of thinking about politics: the rationalist approach, founded on the “argumentation” as a rational means for the non-violent solution of problems (Popper, and the traditionalist mode, inspired by the method of “conversation” as a guarantee of constant openness to the diversity of identities (Oakeshott. To rise from the letters is a mutual influence on the interpretation of the key concepts that characterize the thought of the two authors, which however does not cancel the fundamental divergence of their political orientation.

  3. ["Homesickness and crime"--a contribution of Karl Jaspers to criminal psychology].

    Science.gov (United States)

    Bachhiesl, Sonja Maria

    2009-01-01

    Even a century after its first publication in "Archives of Criminology" (in German: Archiv für Kriminologie), the doctoral thesis of Karl Jaspers (1883-1969), which was newly edited in 1996, continues to be of interest. Although the crimes described by Jaspers, which took place in a rural area, do no longer occur in this form just as the rural culture itself has disappeared, this paper nevertheless contains reflections that may also be relevant for the interpretation of modern potentials of conflict and violence and crimes rooted therein. The former homesickness has developed into novel phenomena of uprooting. In both cases, problems of maladjustment are a contributing factor to crime motivation. Thus despite all terminological and methodological change, Jaspers' thesis is an example for the continuing relevance of certain subjects in criminological discourse.

  4. Karl Popper: La explicación en la disciplina histórica

    Directory of Open Access Journals (Sweden)

    Holbein Giraldo-Paredes

    2013-01-01

    Full Text Available En el siguiente artículo se revisan los argumentos enunciados en la obra La miseria del historicismo, en la cual Karl Popper realiza una crítica a la concepción historicista emanada de la filosofía de autores como Platón, Hegel y Marx. Crítica que realiza aludiendo a argumentos de orden epistemológico, para demostrar que el modelo nomológico deductivo de la explicación no aplica a la disciplina histórica, y en este sentido negando una de las tesis más fuertes que él había defendido toda su vida: la del monismo metodológico o unificacionismo metodológico de la ciencia, heredada del positivismo lógico.

  5. Hurricanes Karl and Tropical Storm Matthew Structure Observed by HIWRAP During GRIP

    Science.gov (United States)

    Heymsfield, G. M.; Guimond, S. R.; Tian, L.

    2012-12-01

    The dual-wavelength (Ku and Ka band) High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) flew for the first time on the Global Hawk during the 2010 Genesis and Rapid Intensification Processes (GRIP). HIWRAP is conical scanning and Doppler, and winds and reflectivity can be mapped within the swath below the Global Hawk. Two interesting cases from the HIWRAP flights were the rapid intensification of Hurricane Karl and the intensification of Tropical Storm Matthew. This presentation will highlight the precipitation and wind structure of these storms during their intensification as derived from the HIWRAP observations. If time permits and if available, highlights from HIWRAP observations from the Hurricane Severe Storm Sentinel (HS3) field campaign in September 2012 will be presented.

  6. Karl Deutsch y su contribución al estudio de las Relaciones Internacionales

    OpenAIRE

    Sánchez Sánchez, Rafael

    2011-01-01

    Este artículo presenta una reseña, y no intenta ser más que eso, de la vida y obra del cientista político Karl Deutsch. Así, presenta aspectos biográficos de la vida de Deutsch. Su extraordinaria y muy activa vida académica. Sus análisis y aportes a las ciencias políticas y las Relaciones Internacionales, poniendo el énfasis en las críticas que hace al realismo político y en su contribución teórica y metodológica al estudio de la integración regional.

  7. Historical consciousness and existential awareness in Karl Barth’s hermeneutics

    Directory of Open Access Journals (Sweden)

    G.M.M. Pelser

    2007-05-01

    Full Text Available Karl Barth’s hermeneutic legacy prolonged Western Christian tradition, especially influenced by Hegelian philosophy of history. This led to Barth’s “theological exegesis” instead of a historic-critical exegesis. In a preceding article Barth’s understanding of the notion “hermeneutic circle” is discussed against the background of the Enlightenment and its counter-movement in Romanticism. In this article Barth’s attitude to the place and role of historical criticism is explained in light of his dialectic distinction between “scientific” and “practical” interpretation. The article aims to show that Barth, with his dialectics, continues Schleiermacher’s realism. In conclusion, the positivistic traits in the Barth legacy are raised once again, in order to open the door to Jürgen Habermas and other deconstructionist thinkers of the postmodern era in hermeneutics.

  8. Karl ernst von Baer's 'Uber Entwickelungsgeschichte der Thiere II' and its unpublished drawings.

    Science.gov (United States)

    Tammiksaar, Erki; Brauckmann, Sabine

    2004-01-01

    In 1828 Karl Ernst von Baer (1792-1876) published his seminal Uber Entwickelungsgeschichte der Thiere. Beobachtung und Reflexion. In the preface he announced that a second volume with one copper plate would be finished 'in a few weeks'. However, it took nine years until the unfinished second volume was released, with four copperplates. In his 'Autobiography', von Baer did not clarify the reasons why he did not finish his research program of comparative embryology. The paper attempts to elucidate them, furnished by archival documents and von Baer's unpublished embryological drawings. Our sketch of a few figures will show that (1) von Baer searched for 'analogies' (homologies) as a unifying principle and (2) explained the mechanisms of embryogenesis by physiological reasoning (electromagnetism). The main objective is to show that technical problems in illustrating and conceptual difficulties impeded von Baer's ambitious research program.

  9. FILSAFAT ILMU KARL R. POPPER DAN THOMAS S. KUHN SERTA IMPLIKASINYA DALAM PENGAJARAN ILMU

    Directory of Open Access Journals (Sweden)

    Slamet Subekti

    2016-04-01

    Full Text Available This article discusses about philosophy of science according to Karl R. Popper and Thomas S. Kuhn. There are similarities and differences between their views about how progress and what function of science.Apparently both Popper and Kuhn agree that science does not proceed by induction. However Kuhn disagrees with the view that science progresses by falsifiability through conjectures and refutations, but occurance by paradigm shift. Popper and Kuhn’s disagreement amounted to a distinction between two functions within the practice of science, one of criticism (Popper and one of puzzle solving (Kuhn.Science education implies the teaching and learning of science interesting and fruitful in one hand, and teachers should be role models to students in the other hand

  10. Karl Marx e a Essência Autogestionária da Comuna de Paris

    Directory of Open Access Journals (Sweden)

    Nildo Viana

    2011-03-01

    Full Text Available

    O artigo apresenta a interpretação da Comuna de Paris por Karl Marx como autogoverno dos produtores, autogestão social. Uma análise minuciosa do capítulo da obra “A Guerra Civil na França” fornece os elementos interpretativos para compreender a percepção da Comuna de Paris como obra autogestionários dos operários parisienses, o que foi um elemento fundamental para o desenvolvimento do marxismo posterior.

  11. Vital forces and organization: philosophy of nature and biology in Karl Friedrich Kielmeyer.

    Science.gov (United States)

    Gambarotto, Andrea

    2014-12-01

    The historical literature on German life science at the end of the 18th century has tried to rehabilitate eighteenth century vitalism by stressing its difference from Naturphilosophie. Focusing on the work of Karl Friedrich Kielmeyer this paper argues that these positions are based on a historiographical bias and that the clear-cut boundary between German vitalism and Naturphilosophie is historically unattested. On the contrary, they both belong to the process of conceptual genealogy that contributed to the project of a general biology. The latter emerged as the science concerned with the laws that regulate the organization of living nature as a whole. The focus on organization was, at least partially, the result of the debate surrounding the notion of "vital force", which originated in the mid-eighteenth century and caused a shift from a regulative to a constitutive understanding of teleology.

  12. Readers and academic reading of Karl Marx (São Paulo, 1958-1964

    Directory of Open Access Journals (Sweden)

    Lidiane Soares Rodrigues

    2016-05-01

    Full Text Available Ideas, books and concepts of Karl Marx and various Marxist authors was incorporated into scientific and cultural institutions. It is one of the political sphere importation into the academic implying sense of speed in relation to its origins and gave to Marxism, through the practices of the agents of this transfer, support for their preservation, dissemination and transformation. Concurrently, there is the incorporation of these lines to the required reading of the humanities and the repertoire of cultivated layers. Examination of appropriations that academic and cultured elites made of Marx, situate them (such work and such elites, institutionally. This is what this article does. Arguing that the legitimacy of the uses of a tradition result not only of their intrinsic value, but the work oriented agents interested in it, is elected an exemplary experience for research. This article looks at two university groups initially focused on the study of Karl Marx's work, made in the late 1950. It begins by proposing a collective biography, the reading program and the various uses they made of them. To refine the analysis and proof the advocated method selects for vertical take, within a group (the first one and a discipline (sociology, two contrasting trajectories (Fernando Henrique Cardoso and Octavio Ianni and various forms Marxism (theoretical and empirical / dominant and dominated. Finally, it discusses the profits propitiated to have operated with three concepts of cultural sociology: habitus, « field » and « patterns of intention » – taken from the works of Pierre Bourdieu and Michael Baxandall.

  13. Subvisible retinal laser therapy: titration algorithm and tissue response.

    Science.gov (United States)

    Lavinsky, Daniel; Sramek, Christopher; Wang, Jenny; Huie, Philip; Dalal, Roopa; Mandel, Yossi; Palanker, Daniel

    2014-01-01

    Laser therapy for diabetic macular edema and other retinal diseases has been used within a wide range of laser settings: from intense burns to nondamaging exposures. However, there has been no algorithm for laser dosimetry that could determine laser parameters yielding a predictable extent of tissue damage. This multimodal imaging and structural correlation study aimed to verify and calibrate a computational model-based titration algorithm for predictable laser dosimetry ranging from nondamaging to intense coagulative tissue effects. Endpoint Management, an algorithm based on a computational model of retinal photothermal damage, was used to set laser parameters for various levels of tissue effect. The algorithm adjusts both power and pulse duration to vary the expected level of thermal damage at different percentages of a reference titration energy dose. Experimental verification was conducted in Dutch Belted rabbits using a PASCAL Streamline 577 laser system. Titration was performed by adjusting laser power to produce a barely visible lesion at 20 ms pulse duration, which is defined as the nominal (100%) energy level. Tissue effects were then determined for energy levels of 170, 120, 100, 75, 50, and 30% of the nominal energy at 1 hour and 3, 7, 30, and 60 days after treatment. In vivo imaging included fundus autofluorescence, fluorescein angiography, and spectral-domain optical coherence tomography. Morphologic changes in tissue were analyzed using light microscopy, as well as scanning and transmission electron microscopy. One hundred and seventy percent and 120% levels corresponded to moderate and light burns, respectively, with damage to retinal pigment epithelium, photoreceptors, and at highest settings, to the inner retina. 50% to 75% lesions were typically subvisible ophthalmoscopically but detectable with fluorescein angiography and optical coherence tomography. Histology in these lesions demonstrated some selective damage to retinal pigment epithelium and

  14. X-ray nanoscopy of cobalt Fischer-Tropsch catalysts at work.

    Science.gov (United States)

    Cats, Korneel H; Gonzalez-Jimenez, Ines D; Liu, Yijin; Nelson, Johanna; van Campen, Douglas; Meirer, Florian; van der Eerden, Ad M J; de Groot, Frank M F; Andrews, Joy C; Weckhuysen, Bert M

    2013-05-21

    Transmission X-ray microscopy has been used to investigate individual Co/TiO2 Fischer-Tropsch (FT) catalyst particles in 2-D and 3-D with 30 nm spatial resolution. Tomographic elemental mapping showed that Co is heterogeneously concentrated in the centre of the catalyst particles. In addition, it was found that Co is mostly metallic during FT at 250 °C and 10 bar. No evidence for Co oxidation was found.

  15. Fischer-Tropsch synthesis and the generation of DME in situ

    Energy Technology Data Exchange (ETDEWEB)

    Zonetti, Priscila C.; Gaspar, Alexandre B.; Appel, Lucia G. [Divisao de Catalise e Processos Quimicos, Instituto Nacional de Tecnologia, Av. Venezuela 82/518, CEP 21081-312, Rio de Janeiro, RJ (Brazil); Mendes, Fabiana M.T. [Divisao de Metrologia de Materiais (DIMAT), Instituto Nacional de Metrologia, Normatizacao e Qualidade Industrial, INMETRO, Av. Nossa Senhora das Gracas 50, CEP 25250-020, Xerem, Duque de Caxias, RJ (Brazil); Sobrinho, Eledir V.; Sousa-Aguiar, Eduardo F. [CENPES/Petrobras, Ilha do Fundao, quadra 7, Cidade Universitaria, 21949-900, Rio de Janeiro (Brazil)

    2010-05-15

    Ternary physical mixtures comprised a Fischer-Tropsch catalyst, a methanol synthesis catalyst and a zeolite employed in the hydrocarbon synthesis from syngas. Two Fe-based catalysts (i.e., one promoted by K and the other by Ru), two HY zeolites with different acidities, a commercial HZSM-5 and Cu/ZnO/Al{sub 2}O{sub 3} (methanol synthesis catalyst) were used in these systems. The main products obtained were dimethyl ether, methanol and hydrocarbons. First of all, it was observed that by adding Cu/ZnO/Al{sub 2}O{sub 3} catalyst to a binary physical mixture comprised of a Fischer-Tropsch catalyst and HZSM-5, the CO conversion increases more than 20 times. Second, during the reaction transient period the dimethyl ether selectivity decreases as the conversion increases. Third, the hydrocarbons synthesized followed the ASF distribution in the C{sub 1}-C{sub 12} range and finally, it was also verified that the Y zeolites and the Fischer-Tropsch synthesis catalyst promoted by Ru generated the most active physical mixtures. The results showed that the role of zeolites in the ternary physical mixture is only associated with the dimethyl ether synthesis. The following reaction pathway was suggested: first, methanol is synthesized from syngas using Cu/ZnO/Al{sub 2}O{sub 3} catalyst; after that, this alcohol is dehydrated by an acid catalyst generating DME; and lastly, DME initiates Fischer-Tropsch synthesis, which is then propagated by CO. (author)

  16. Visualization of the relationship between Fischer and Haworth projections of monosaccharides by animation on a microcomputer.

    Science.gov (United States)

    Ewart, J F; Kirby, G H; Rayner, J D

    1994-06-01

    An animation is described to assist in the visualization of the relationship between the Fischer and Haworth projections of monosaccharides. The animation helps the understanding of two quite different, commonly used representations of the same molecule. The animation runs on a 386-based PC with VGA graphics. The method for realizing such an animation on this hardware is described in detail; C code is provided in the Appendix.

  17. Nano-sized cobalt based Fischer-Tropsch catalysts for gas-to-liquid process applications.

    Science.gov (United States)

    Kang, Jung Shik; Awate, S V; Lee, Yun Ju; Kim, So Jung; Park, Moon Ju; Lee, Sang Deuk; Hong, Suk-In; Moon, Dong Ju

    2010-05-01

    Nano-sized cobalt supported catalysts were prepared for Fischer-Tropsch synthesis in gas-to-liquid (GTL) process. The dependence of crystallite size and reducibility of Co3O4 on the supports were investigated with FTS activity. XRD peaks revealed nano crystallites ( Co/Al2O3 (70.0%) > Co/R_TiO2 (61%) > Co/A_TiO2 (57.5%).

  18. Computational chemistry insights in the REDOX Behaviour of Cr and W Fischer carbene complexes

    Science.gov (United States)

    Landman, Marile; Conradie, Jeanet; van Rooyen, Petrus H.

    2015-09-01

    An electrochemical study of a series of Fischer carbene complexes containing a hetero-aryl group showed that Cr and W carbenes exhibit different electrochemical behaviour. The Cr carbenes are oxidized in two one electron oxidation processes, namely Cr(0) to Cr(I) and Cr(I) to Cr(II). On the contrary, Fischer carbene complexes of tungsten are directly oxidized from W(0) to W(II). The first reduction process observed for both W- and Cr- carbenes, is a one electron process. A density functional theory (DFT) computational chemistry study of the electronic structure of the Cr- and W-carbenes, showed that the oxidation is metal based and the reduction is located on the carbene ligand. The DFT calculations further showed that the Cr(II) species is a triplet and the W(II) species a closed shell singlet. The DFT calculated energies of the HOMO and LUMO of the neutral carbenes relate linearly to the experimental oxidation and reduction potential, respectively. These mathematical relationships obtained can be used to predict experimentally measured potentials of related Fischer carbene complexes.

  19. Synthesis in situ of gold nanoparticles by a dialkynyl Fischer carbene complex anchored to glass surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Bertolino, María Candelaria, E-mail: cbertolino@fcq.unc.edu.ar; Granados, Alejandro Manuel, E-mail: ale@fcq.unc.edu.ar

    2016-10-15

    Highlights: • Fischer carbene 1-W reacts via cycloaddition without Cu(I) with azide terminal surface. • This reaction on the surface is regioselective to internal triple bond of 1-W. • 1-W bound to glass surface produce AuNps in situ fixed to the surface. • This ability is independent of how 1-W is bonded to the surface. • This hybrid surface can be valuable as SERS substrate or in heterogeneous catalysis. - Abstract: In this work we present a detailed study of classic reactions such as “click reaction” and nucleophilic substitution reaction but on glass solid surface (slides). We used different reactive center of a dialkynylalcoxy Fischer carbene complex of tungsten(0) to be anchored to modified glass surface with amine, to obtain aminocarbene, and azide terminal groups. These cycloaddition reaction showed regioselectivity to internal triple bond of dialkynyl Fischer carbene complex without Cu(I) as catalyst. Anyway the carbene anchored was able to act as a reducing agent to produce in situ very stable gold nanoparticles fixed on surface. We showed the characterization of modified glasses by contact angle measurements and XPS. Synthesized nanoparticles were characterized by SEM, XPS, EDS and UV–vis. The modified glasses showed an important enhancement Raman-SERS. This simple, fast and robust method to create a polifunctional and hybrid surfaces can be valuable in a wide range of applications such as Raman-SERS substrates and other optical fields.

  20. Isothermal Titration Calorimetry for Measuring Macromolecule-Ligand Affinity

    Science.gov (United States)

    Duff,, Michael R.; Grubbs, Jordan; Howell, Elizabeth E.

    2011-01-01

    Isothermal titration calorimetry (ITC) is a useful tool for understanding the complete thermodynamic picture of a binding reaction. In biological sciences, macromolecular interactions are essential in understanding the machinery of the cell. Experimental conditions, such as buffer and temperature, can be tailored to the particular binding system being studied. However, careful planning is needed since certain ligand and macromolecule concentration ranges are necessary to obtain useful data. Concentrations of the macromolecule and ligand need to be accurately determined for reliable results. Care also needs to be taken when preparing the samples as impurities can significantly affect the experiment. When ITC experiments, along with controls, are performed properly, useful binding information, such as the stoichiometry, affinity and enthalpy, are obtained. By running additional experiments under different buffer or temperature conditions, more detailed information can be obtained about the system. A protocol for the basic setup of an ITC experiment is given. PMID:21931288

  1. Isothermal titration calorimetry of ion-coupled membrane transporters.

    Science.gov (United States)

    Boudker, Olga; Oh, SeCheol

    2015-04-01

    Binding of ligands, ranging from proteins to ions, to membrane proteins is associated with absorption or release of heat that can be detected by isothermal titration calorimetry (ITC). Such measurements not only provide binding affinities but also afford direct access to thermodynamic parameters of binding--enthalpy, entropy and heat capacity. These parameters can be interpreted in a structural context, allow discrimination between different binding mechanisms and guide drug design. In this review, we introduce advantages and limitations of ITC as a methodology to study molecular interactions of membrane proteins. We further describe case studies where ITC was used to analyze thermodynamic linkage between ions and substrates in ion-coupled transporters. Similar type of linkage analysis will likely be applicable to a wide range of transporters, channels, and receptors. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Isothermal titration calorimetry of membrane proteins - progress and challenges.

    Science.gov (United States)

    Rajarathnam, Krishna; Rösgen, Jörg

    2014-01-01

    Integral membrane proteins, including G protein-coupled receptors (GPCR) and ion channels, mediate diverse biological functions that are crucial to all aspects of life. The knowledge of the molecular mechanisms, and in particular, the thermodynamic basis of the binding interactions of the extracellular ligands and intracellular effector proteins is essential to understand the workings of these remarkable nanomachines. In this review, we describe how isothermal titration calorimetry (ITC) can be effectively used to gain valuable insights into the thermodynamic signatures (enthalpy, entropy, affinity, and stoichiometry), which would be most useful for drug discovery studies, considering that more than 30% of the current drugs target membrane proteins. This article is part of a Special Issue entitled: Structural and biophysical characterisation of membrane protein-ligand binding. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. IMPEDANCE METHOD OF MEASURING OF THE TITRATABLE ACIDITY OF YOGURT

    Directory of Open Access Journals (Sweden)

    Miroslav Vasilev

    2016-10-01

    Full Text Available In the present work are analyzed studies related to changes in the active impedance component of the dairy environment caused by the flow of lactic fermentation and coagulation of casein in milk. The aim of this work was to determine the relationship between the relative change of titratable acidity and the relative change of active impedance component of the dairy environment with lactic fermentation, causing coagulation of the casein in milk. . The data were interpolated with cubic spline, visualizing how when the fat content increases, the electrical resistance increases too. All data, collected during the tests would complement and be used for solving the optimization problem to determine the time of completion of the coagulation in future work.

  4. Biophysical characterization of antibodies with isothermal titration calorimetry

    Directory of Open Access Journals (Sweden)

    Verna Frasca

    2016-07-01

    Full Text Available Antibodies play a key role in the immune response. Since antibodies bind antigens with high specificity and tight affinity, antibodies are an important reagent in experimental biology, assay development, biomedical research and diagnostics. Monoclonal antibodies are therapeutic drugs and used for vaccine development. Antibody engineering, biophysical characterization, and structural data have provided a deeper understanding of how antibodies function, and how to make better drugs. Isothermal titration calorimetry (ITC is a label-free binding assay, which measures affinity, stoichiometry, and binding thermodynamics for biomolecular interactions. When thermodynamic data are used together with structural and kinetic data from other assays, a complete structure-activity-thermodynamics profile can be constructed. This review article describes ITC, and discusses several applications on how data from ITC provides insights into how antibodies function, guide antibody engineering, and aid design of new therapeutic drugs.

  5. Determination of Dimethylallylamine by Titration in Nonaqueous Solvent

    Institute of Scientific and Technical Information of China (English)

    LIU Li-hua; GONG Zhu-qing; ZHENG Ya-jie

    2004-01-01

    The content of dimethylallylamine was determined using glacial acetic acid as solvent, acetic-formic mixture as an anhydrite, perchloric acid-glacial acetic acid as titrant, and 1% crystal violet in acetic acid as indicator in the presence of methylamine and dimethylamine The influences of inert constituents and water on the titration were investigated, and a complete analytical method was determined. The results showed that the determination error of total amines increased with water increasing, while the effect of water on the determination of dimethylallylamine was little when the amount of water was within 5%, the relative error was generally within 1%, and that the end-point was acutely when about 10% chloroform was added. Compared with gas chromatography, this method is simple, convenient and accurate.

  6. A microfabrication-based approach to quantitative isothermal titration calorimetry.

    Science.gov (United States)

    Wang, Bin; Jia, Yuan; Lin, Qiao

    2016-04-15

    Isothermal titration calorimetry (ITC) directly measures heat evolved in a chemical reaction to determine equilibrium binding properties of biomolecular systems. Conventional ITC instruments are expensive, use complicated design and construction, and require long analysis times. Microfabricated calorimetric devices are promising, although they have yet to allow accurate, quantitative ITC measurements of biochemical reactions. This paper presents a microfabrication-based approach to integrated, quantitative ITC characterization of biomolecular interactions. The approach integrates microfabricated differential calorimetric sensors with microfluidic titration. Biomolecules and reagents are introduced at each of a series of molar ratios, mixed, and allowed to react. The reaction thermal power is differentially measured, and used to determine the thermodynamic profile of the biomolecular interactions. Implemented in a microdevice featuring thermally isolated, well-defined reaction volumes with minimized fluid evaporation as well as highly sensitive thermoelectric sensing, the approach enables accurate and quantitative ITC measurements of protein-ligand interactions under different isothermal conditions. Using the approach, we demonstrate ITC characterization of the binding of 18-Crown-6 with barium chloride, and the binding of ribonuclease A with cytidine 2'-monophosphate within reaction volumes of approximately 0.7 µL and at concentrations down to 2mM. For each binding system, the ITC measurements were completed with considerably reduced analysis times and material consumption, and yielded a complete thermodynamic profile of the molecular interaction in agreement with published data. This demonstrates the potential usefulness of our approach for biomolecular characterization in biomedical applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Size dependent stability of cobalt nanoparticles on silica under high conversion Fischer-Tropsch environment.

    Science.gov (United States)

    Wolf, Moritz; Kotzé, Hendrik; Fischer, Nico; Claeys, Michael

    2017-02-15

    Highly monodisperse cobalt crystallites, supported on Stöber silica spheres, as model catalysts for the Fischer-Tropsch synthesis were exposed to simulated high conversion environments in the presence and absence of CO utilising an in house developed in situ magnetometer. The catalyst comprising the smallest crystallites in the metallic state (average diameter of 3.2 nm) experienced pronounced oxidation whilst the ratio of H2O to H2 was increased stepwise to simulate CO conversions from 26% up to complete conversion. Direct exposure of this freshly reduced catalyst to a high conversion Fischer-Tropsch environment resulted in almost spontaneous oxidation of 40% of the metallic cobalt. In contrast, a model catalyst with cobalt crystallites of 5.3 nm only oxidised to a small extent even when exposed to a simulated conversion of over 99%. The largest cobalt crystallites were rather stable and only experienced measurable oxidation when subjected to H2O in the absence of H2. This size dependency of the stability is in qualitative accordance with reported thermodynamic calculations. However, the cobalt crystallites showed an unexpected low susceptibility to oxidation, i.e. only relatively high ratios of H2O to H2 partial pressure caused oxidation. Similar experiments in the presence of CO revealed the significance of the actual Fischer-Tropsch synthesis on the metallic surface as the dissociation of CO, an elementary step in the Fischer-Tropsch mechanism, was shown to be a prerequisite for oxidation. Direct oxidation of cobalt to CoO by H2O seems to be kinetically hindered. Thus, H2O may only be capable of indirect oxidation, i.e. high concentrations prevent the removal of adsorbed oxygen species on the cobalt surface leading to oxidation. However, a spontaneous direct oxidation of cobalt at the interface between the support and the crystallites by H2O forming presumably cobalt silicate type species was observed in the presence and absence of CO. The formation of these

  8. Quick titration of pergolide in cotreatment with domperidone is safe and effective

    NARCIS (Netherlands)

    Jansen, PAF; Herings, RMC; Samson, MM; Schuurmans-Daemen, LMPJ; Hovestadt, A; Verhaar, HJJ; Van Laar, T; de Vreede, P.

    2001-01-01

    The purpose of the study was to analyze efficacy and safety of quick pergolide titration combined with domperidone. In an open-label prospective study, pergolide was titrated in 16 days to a maximum of 3 mg/d doses as adjunctive treatment to L-Dopa in 10 elderly patients with Parkinson's disease. Si

  9. A Laser-Pointer-Based Spectrometer for Endpoint Detection of EDTA Titrations

    Science.gov (United States)

    Dahm, Christopher E.; Hall, James W.; Mattioni, Brian E.

    2004-01-01

    A laser spectrometer for the ethylenediaminetetra-acetic acid (EDTA) titration of magnesium or calcium ions that is designed around a handheld laser pointer as the source and a photoresistor as the detector is developed. Findings show that the use of the spectrometer reduces the degree of uncertainty and error in one part of the EDTA titrations,…

  10. The ion-sensitive field effect transistor in rapid acid-base titrations

    NARCIS (Netherlands)

    Bos, M.; Bergveld, P.; Veen-Blaauw, van A.M.W.

    1979-01-01

    Ion-sensitive field effect transistors (ISFETs) are used as the pH sensor in rapid acid—base titrations. Titration speeds at least five times greater than those with glass electrodes are possible for accuracies better than ±1%.

  11. A knowledge based advisory system for acid/base titrations in non-aqueous solvents

    NARCIS (Netherlands)

    Bos, M.; Linden, van der W.E.

    1996-01-01

    A computer program was developed that could advice on the choice of solvent and titrant for acid/base titrations in nonaqueous media. It is shown that the feasibility of a titration in a given solvent can be calculated from solvent properties and intrinsic acid/base properties of the sample componen

  12. Quick titration of pergolide in cotreatment with domperidone is safe and effective

    NARCIS (Netherlands)

    Jansen, PAF; Herings, RMC; Samson, MM; Schuurmans-Daemen, LMPJ; Hovestadt, A; Verhaar, HJJ; Van Laar, T; de Vreede, P.

    2001-01-01

    The purpose of the study was to analyze efficacy and safety of quick pergolide titration combined with domperidone. In an open-label prospective study, pergolide was titrated in 16 days to a maximum of 3 mg/d doses as adjunctive treatment to L-Dopa in 10 elderly patients with Parkinson's disease.

  13. High IFN-α expression is associated with the induction of experimental autoimmune uveitis (EAU) in Fischer 344 rat

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Thl-response plays a crucial role in determining pathogenesis of organ-specific autoimmune diseases. It is believed that both IL-12 and INF-α are initiators to regulate Th1- response. In our experimental autoimmune uveitis (EAU) model, both Lewis and Fischer 344 rats share the same MHC class ⅡI molecules,while Lewis rat is EAU susceptible and Fischer 344 rat is EAU resistant. However, under the same condition of immunization, if pertussis toxin (PTX) was injected intraperitoneally as an additional adjuvant, Fischer 344 rat can develop EAU. In this study we investigate which mechanisms are involved in the induction of EAU in CFA+R16+PTX-treated (CRP-treated) Fischer 344 rats. In vivo and in vitro data demonstrated that Thl-cytokine, IFN-γ mRNA expression was significantly increased in disease target tissue-eyes and in draining lymph node cells of CRP-treated Fischer 344 rat. When IL-12 and IFN-α mRNA expression were compared in the experimental groups, only IFN-α mRNA expression was associated with EAU development.To distinguish the sources of IFN-α producing cells, it was observed that IFN-α expression was mainly produced by macrophages. It was further confirmed that normal macrophage from Fischer 344 rat was able to produce significant IFN-α in the presence of PTX. The data strongly suggested that IFN-α might be involved in initiating Thl-cell differentiation and in turn contribute to the induction of EAU. High IFN-αexpression induced by PTX may represent a novel pathway to initiate Thl response in Fischer 344 rat.

  14. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : 1998 Annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 1998 calendar year. The report begins...

  15. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : 1999 Annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 1999 calendar year. The report begins...

  16. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : 2002 Annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 2002 calendar year. The report begins...

  17. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : 2001 Annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 2001 calendar year. The report begins...

  18. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : 1994 Annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 1994 calendar year. The report begins...

  19. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : 1997 Annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 1997 calendar year. The report begins...

  20. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : Updated- 2003 annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 2003 calendar year. The report begins...

  1. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : 1995 Annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 1995 calendar year. The report begins...

  2. Annual narrative report: Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, and Lake Andes Wetland Management District: Calendar year 1975

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This collection of monthly activity reports summarizes activities on Lake Andes NWR, Lake Andes WMD, and Karl E. Mundt NWR during the 1975 calendar year. Resource...

  3. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : 2000 Annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 2000 calendar year. The report begins...

  4. Lake Andes National Wildlife Refuge Complex : Lake Andes National Wildlife Refuge, Karl Mundt National Wildlife Refuge, Lake Andes Wetland Management District : 1996 Annual narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Lake Andes NWR, Karl Mundt NWR, and Lake Andes WMD outlines Refuge accomplishments during the 1996 calendar year. The report begins...

  5. Study and Application of a New On—Line Titration Technique

    Institute of Scientific and Technical Information of China (English)

    朱建育; 施利毅; 等

    2002-01-01

    A new on-line titration method and device based on a new technique-continuous flow titration is described.By the means of electronically controlled switching of a solenoid valve,the main component of the system,the equivalent point of the titration is easily determined.Several kinds of mixing tools were examined.whereby a self-made mixing chamer with minimum volume gave best results and was therefore used in the dveice,The error of the titration is within 0.2% and the relative standard deviation(RSD) is below 1.2%,The results show no difference compared with a commercial device,meanwhile the new on-line titration system is cheaper and fully automated and thus easy to hand and less slovent consumption.

  6. SPECIAL CONSIDERATIONS REGARDING WARFARIN DOSE TITRATION IN PATIENTS WITH ATRIAL FIBRILLATION DEPENDING ON CLINICAL FACTORS

    Directory of Open Access Journals (Sweden)

    E. L. Artanova

    2011-01-01

    Full Text Available Aim. To study the relations of clinical characteristics and individual warfarin dose titration in patients with atrial fibrillation. Material and methods. Period of warfarin dose titration was analyzed in 68 patients with atrial fibrillation due to ischemic heart disease. Adjusted warfarin dose in milligram, duration of dose titration in days and maximal international normalized ratio (INR were taken into account. Sex, age, history of myocardial infarction and stroke, concomitant diseases, amiodarone therapy were considered among clinical characteristics. Results. Adjusted warfarin dose was significantly higher in obesity , and it was lower in case of experienced myocardial infarction. The INR highest levels and maximal amplitudes of its fluctuations were observed in patients with thyroid gland nodes and smokers. Period of warfarin dose titration was longer in patients treated with amiodarone. Conclusion. Warfarin dose titration in patients with atrial fibrillation depends on the presence of myocardial infarction, obesity , thyroid nodular changes, smoking and amiodarone treatment.

  7. Integration and global analysis of isothermal titration calorimetry data for studying macromolecular interactions.

    Science.gov (United States)

    Brautigam, Chad A; Zhao, Huaying; Vargas, Carolyn; Keller, Sandro; Schuck, Peter

    2016-05-01

    Isothermal titration calorimetry (ITC) is a powerful and widely used method to measure the energetics of macromolecular interactions by recording a thermogram of differential heating power during a titration. However, traditional ITC analysis is limited by stochastic thermogram noise and by the limited information content of a single titration experiment. Here we present a protocol for bias-free thermogram integration based on automated shape analysis of the injection peaks, followed by combination of isotherms from different calorimetric titration experiments into a global analysis, statistical analysis of binding parameters and graphical presentation of the results. This is performed using the integrated public-domain software packages NITPIC, SEDPHAT and GUSSI. The recently developed low-noise thermogram integration approach and global analysis allow for more precise parameter estimates and more reliable quantification of multisite and multicomponent cooperative and competitive interactions. Titration experiments typically take 1-2.5 h each, and global analysis usually takes 10-20 min.

  8. Theodor Billroth's vision and Karl Ziegler's action: commemoration of the 40th day of death and the 50th anniversary of conferment of Nobel Prize for Chemistry of Karl Ziegler.

    Science.gov (United States)

    Kapischke, Matthias; Pries, Alexandra

    2014-02-01

    Alloplastic materials are broadly used in modern surgery. Until the middle of the 20th century, metal materials and especially silver were used because of their antimicrobial properties. With the development of a new catalytic process for the production of high-density polyethylene and polypropylene materials, a new era of prosthesis was introduced. These polymers are integral part of our everyday operations surgery, especially in hernia repair. The famous surgeon Billroth mentioned to his pupil Czerny in 1878: "If we could artificially produce tissues of the density and toughness of fascia and tendon, the secret of the radical cure of hernia would be discovered". The polypropylene developed by Karl Ziegler gave the surgeon a material for daily practice, which in its properties (nearly) achieved Billroth's initial vision. In 1963 the Nobel Prize for Chemistry was awarded to Karl Ziegler and Giulio Natta in Stockholm. Furthermore, August 11, 2013 will be the 40th anniversary of Karl Ziegler's death. This manuscript honors both days.

  9. A tectonic window into the crystalline basement of Prins Karls Forland, Svalbard

    Science.gov (United States)

    Faehnrich, Karol; Manecki, Maciej; Schneider, David; Czerny, Jerzy; Myhre, Per Inge; Majka, Jarosław; Kośmińska, Karolina; Barnes, Chris; Maraszewska, Maria

    2016-04-01

    Prins Karls Forland, Svalbard, comprises a fold-thrust belt as a result of the Eocene Eurekan orogeny. The northern part of the island (north of Selvågen) is dominated by Neoproterozoic siliciclastic metasediments regionally metamorphosed to greenschist facies conditions, probably in association with one distinct stage of Caledonian tectonism. Contrasting with these low grade sequences are rocks of the Pinkie Unit, which are locally exposed along east coast of Prins Karls Forland. Amphibolite facies metasediments show evidence for at least two distinct deformation stages (including mylonitization). All the borders of the Pinkie unit are tectonic: to the east, it is a sharp boundary with the truncation of the Pinkie foliation into a N-S fault, parallel to the coast, probably associated with the formation of the Neogene Forlandsundet Graben. A ~1 km wide ductile to brittle shear zone (the Bouréefjellet shear zone) separates the low and high grade sequences along the western margin, with the Grampian Formation (low metamorphic grade quartzites, conglomerates, siltstones and slates) as the upper structural unit. Moreover, the shear zone contains outcrops of metagabbro associated with magnetite ore (Maraszewska et al. 2016, EGU). The apparent tectonostratigraphy of the Pinkie unit consists of laminated fine-grained calc-silicate rocks, locally with scapolite, and a strong E-W lineation at lower structural levels. In these rocks primary layering is apparent (S0) and parallel to metamorphic foliation plane (S1). Interconnected elongated mica crystals within S1 are deformed by C'-type shear zones. They are overlain by garnet-bearing quartzite-mylonites and garnet-bearing mylonitic mica schists with N-S to NW-SE lineations at upper structural levels. Kośmińska et al. (2015a, Mineralogia - Special Papers, vol. 44, 61-62) determined P-T metamorphic conditions of garnet-mica schist of 7-9 kbar and 550-650°C. The dominant population of metamorphic monazite present in

  10. Eurekan deformation on Prins Karls Forland, Svalbard - new insights from Ar40/Ar39 muscovite dating

    Science.gov (United States)

    Faehnrich, Karol; Schneider, David; Manecki, Maciej; Czerny, Jerzy; Myhre, Per Inge; Majka, Jarosław; Kośmińska, Karolina; Barnes, Christopher; Maraszewska, Maria

    2017-04-01

    Eurekan deformation has been proven to be a complex sequence of tectonic episodes, dominated by compression in the Circum Arctic region. It was associated with early Cenozoic collision of Eurasia, North America and Greenland plates producing fold-thrust belt style of deformation. Timing of this enigmatic event has not yet been extensively resolved by radiometric dating (Piepjohn et al. 2016, Journal of the Geological Society, 173(6), 1007-1024). Reinhardt et al. (2013, Z. Dt. Ges. Geowiss., 164 (1), 131-147) dated syn-tectonic volcanic ashes at c. 60 Ma and 54 Ma on Ellesmere Island, Canada. Tagner et al. (2011, Earth and Planetary Science Letters, 303(3), 203-214) interpreted c. 49-47 Ma 40Ar/39Ar ages on trachyte flows in northern Greenland as peak compression during the Eurekan event. On Svalbard, Tessensohn et al. (2001, Geologisches Jahrbuch, B 91, 83-104) reported K/Ar whole rock ages ranging from c. 67 to 49 Ma for the slates from Svartfjella-Eidembukta-Daudmannsodden Lineament. Bentonite layers in the Central Tertiary Basin are as young as c. 56 Ma (Charles et al. 2011, Geochem. Geophys. Geosyst., 12, 1-19), predating latest deformation. Moreover, Barnes et al (2017, in prep.) applied (U-Th)/He thermochronology along the western margin of Svalbard and resolved Early to Middle Eocene heating, likely documenting burial related to thrusting. Here we present new results from 40Ar/39Ar muscovite dating of ductile to brittle shear zone on Prins Karls Forland, Svalbard, indicating Eurekan age of thrusting. Prins Karls Forland is dominated by Neoproterozoic siliciclastic metasediments (comprising Caledonian basement) regionally metamorphosed to greenschist facies conditions. A ˜1 km wide ductile to brittle shear zone (the Bouréefjellet shear zone) separates the amphibolite facies Pinkie Unit from the lower grade upper structural unit, the Grampianfjella Formation (Faehnrich et al. 2016, EGU 2016). The age of the amphibolite facies metamorphism (c. 370-355 Ma

  11. Volume Measurements of Laser-generated Pits for In Situ Geochronology using KArLE (Potassium-Argon Laser Experiment)

    Science.gov (United States)

    French, R. A.; Cohen, B. A.; Miller, J. S.

    2014-01-01

    The Potassium-Argon Laser Experiment( KArLE), is composed of two main instruments: a spectrometer as part of the Laser-Induced Breakdown Spectroscopy (LIBS) method and a Mass Spectrometer (MS). The LIBS laser ablates a sample and creates a plasma cloud, generating a pit in the sample. The LIBS plasma is measured for K abundance in weight percent and the released gas is measured using the MS, which calculates Ar abundance in mols. To relate the K and Ar measurements, total mass of the ablated sample is needed but can be difficult to directly measure. Instead, density and volume are used to calculate mass, where density is calculated based on the elemental composition of the rock (from the emission spectrum) and volume is determined by pit morphology. This study aims to reduce the uncertainty for KArLE by analyzing pit volume relationships in several analog materials and comparing methods of pit volume measurements and their associated uncertainties.

  12. [Anorexia nervosa in light of Karl Jaspers and Erich Fromm's ideas and social constructivism--hypotheses and thoughts].

    Science.gov (United States)

    Talarczyk, Małgorzata

    2012-01-01

    The point of the article is to analyse and reflect on certain symptoms of anorexia nervosa in light of Karl Jaspers and Erich Fromm's ideas and social constructivism. Contemplating the disorder in view of the philosophical ideas mentioned earlier, the author analyses such aspects of patients as: functioning on the verge of life and death, the paradoxical struggle to escape from freedom in search of independence, as well as various understandings and descriptions of anorexia in consideration of social constructivism. The author shares thoughts and poses hypotheses, trying to view anorexia in light of selected philosophical and psychological ideas, which in their general assumptions were not concerned with defining nor analysing anorexia nervosa. In view of Karl Jaspers' ideas, the author focuses on the so called 'limit-situations', in the ideas of Erich Fromm she takes notice in "Escape from Freedom" to new relations. Finally in the light of social constructivism the author focuses on the cultural context.

  13. Sigmund Freud (1856-1939) and Karl Köller (1857-1944) and the discovery of local anesthesia.

    Science.gov (United States)

    dos Reis, Almiro

    2009-01-01

    The understanding, occasionally recognized, that Sigmund Freud had the intuition to use cocaine as local anesthetic for surgical procedures, or even that he played any role in the discovery of local anesthesia is not true. The objective of Freud's studies were different, and based in irrefutable evidence, Karl Köller was the real inventor of local anesthesia. In face of those facts, proper knowledge of this historically important subject is due. This report refers to the long-known properties of cocaine. It also remembers personal data, and the professional and scientific activities of Sigmund Freud and Karl Köller. It presents Freud's researches on the pathophysiological effects of cocaine. It exposes the reasons for the harsh criticism of Freud's concepts. It describes the sudden, but conscious and justified, idea of Karl Köller to study scientifically the use of cocaine as a local anesthetic in animals and humans. It indicates how those pioneering studies, that culminated with the discovery of local anesthesia by Köller and two presentations in Vienna on the subject, were done. It also reports the first ophthalmologic surgery under local anesthesia. It shows the immediate dissemination throughout the world of the discovery that marked the beginning of regional blocks. It comments several documents corroborating the role of Köller in this discovery. And, finally, it mentions the numerous homages received by Köller in different areas of the world. COCLUSIONS: Regional block was introduced by Karl Köller in 1884, when he demonstrated the feasibility of performing painless ophthalmologic surgeries by using cocaine as a local anesthetic. Sigmund Freud studied cocaine extensively, but he did not have direct participation in this important discovery.

  14. [Determination of low-carbon alcohols, aldehydes and ketones in aqueous products of Fischer-Tropsch synthesis by gas chromatography].

    Science.gov (United States)

    Gai, Qingqing; Wu, Peng; Shi, Yulin; Bai, Yu; Long, Yinhua

    2015-01-01

    A method for the determination of low-carbon (C1-C8) alcohols, aldehydes and ketones in aqueous products of Fischer-Tropsch synthesis was developed by gas chromatography. It included the optimization of separation conditions, the precision and accuracy of determination, and the use of correction factors of the analytes to ethanol for quantification. The aqueous products showed that the correlation coefficients for ethanol in different content ranges were above 0.99, which means it had good linear correlations. The spiked recoveries in the aqueous samples of Fischer-Tropsch synthesis were from 93.4% to 109.6%. The accuracy of the method can satisfy the requirement for the analysis of the aqueous samples of Fischer-Tropsch synthesis. The results showed that the total mass fractions of the major low-carbon alcohols, aldehydes, ketones in aqueous products of Fischer-Tropsch synthesis were about 3%-12%, and the contents of ethanol were the highest (about 1.7%-7.3%). The largest share of the total proportion was n-alcohols, followed by isomeric alcohols, aldehydes and ketones were the lowest. This method is simple, fast, and has great significance for the analysis of important components in aqueous products of Fischer-Tropsch synthesis.

  15. Hot biological catalysis: isothermal titration calorimetry to characterize enzymatic reactions.

    Science.gov (United States)

    Mazzei, Luca; Ciurli, Stefano; Zambelli, Barbara

    2014-04-04

    Isothermal titration calorimetry (ITC) is a well-described technique that measures the heat released or absorbed during a chemical reaction, using it as an intrinsic probe to characterize virtually every chemical process. Nowadays, this technique is extensively applied to determine thermodynamic parameters of biomolecular binding equilibria. In addition, ITC has been demonstrated to be able of directly measuring kinetics and thermodynamic parameters (kcat, KM, ΔH) of enzymatic reactions, even though this application is still underexploited. As heat changes spontaneously occur during enzymatic catalysis, ITC does not require any modification or labeling of the system under analysis and can be performed in solution. Moreover, the method needs little amount of material. These properties make ITC an invaluable, powerful and unique tool to study enzyme kinetics in several applications, such as, for example, drug discovery. In this work an experimental ITC-based method to quantify kinetics and thermodynamics of enzymatic reactions is thoroughly described. This method is applied to determine kcat and KM of the enzymatic hydrolysis of urea by Canavalia ensiformis (jack bean) urease. Calculation of intrinsic molar enthalpy (ΔHint) of the reaction is performed. The values thus obtained are consistent with previous data reported in literature, demonstrating the reliability of the methodology.

  16. Application of isothermal titration calorimetry in bioinorganic chemistry.

    Science.gov (United States)

    Grossoehme, Nicholas E; Spuches, Anne M; Wilcox, Dean E

    2010-11-01

    The thermodynamics of metals ions binding to proteins and other biological molecules can be measured with isothermal titration calorimetry (ITC), which quantifies the binding enthalpy (ΔH°) and generates a binding isotherm. A fit of the isotherm provides the binding constant (K), thereby allowing the free energy (ΔG°) and ultimately the entropy (ΔS°) of binding to be determined. The temperature dependence of ΔH° can then provide the change in heat capacity (ΔC (p)°) upon binding. However, ITC measurements of metal binding can be compromised by undesired reactions (e.g., precipitation, hydrolysis, and redox), and generally involve competing equilibria with the buffer and protons, which contribute to the experimental values (K (ITC), ΔH (ITC)). Guidelines and factors that need to be considered for ITC measurements involving metal ions are outlined. A general analysis of the experimental ITC values that accounts for the contributions of metal-buffer speciation and proton competition and provides condition-independent thermodynamic values (K, ΔH°) for metal binding is developed and validated.

  17. Characterization of membrane protein interactions by isothermal titration calorimetry.

    Science.gov (United States)

    Situ, Alan J; Schmidt, Thomas; Mazumder, Parichita; Ulmer, Tobias S

    2014-10-23

    Understanding the structure, folding, and interaction of membrane proteins requires experimental tools to quantify the association of transmembrane (TM) helices. Here, we introduce isothermal titration calorimetry (ITC) to measure integrin αIIbβ3 TM complex affinity, to study the consequences of helix-helix preorientation in lipid bilayers, and to examine protein-induced lipid reorganization. Phospholipid bicelles served as membrane mimics. The association of αIIbβ3 proceeded with a free energy change of -4.61±0.04kcal/mol at bicelle conditions where the sampling of random helix-helix orientations leads to complex formation. At bicelle conditions that approach a true bilayer structure in effect, an entropy saving of >1kcal/mol was obtained from helix-helix preorientation. The magnitudes of enthalpy and entropy changes increased distinctly with bicelle dimensions, indicating long-range changes in bicelle lipid properties upon αIIbβ3 TM association. NMR spectroscopy confirmed ITC affinity measurements and revealed αIIbβ3 association and dissociation rates of 4500±100s(-1) and 2.1±0.1s(-1), respectively. Thus, ITC is able to provide comprehensive insight into the interaction of membrane proteins. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Enzyme kinetics determined by single-injection isothermal titration calorimetry.

    Science.gov (United States)

    Transtrum, Mark K; Hansen, Lee D; Quinn, Colette

    2015-04-01

    The purposes of this paper are (a) to examine the effect of calorimeter time constant (τ) on heat rate data from a single enzyme injection into substrate in an isothermal titration calorimeter (ITC), (b) to provide information that can be used to predict the optimum experimental conditions for determining the rate constant (k2), Michaelis constant (KM), and enthalpy change of the reaction (ΔRH), and (c) to describe methods for evaluating these parameters. We find that KM, k2 and ΔRH can be accurately estimated without correcting for the calorimeter time constant, τ, if (k2E/KM), where E is the total active enzyme concentration, is between 0.1/τ and 1/τ and the reaction goes to at least 99% completion. If experimental conditions are outside this domain and no correction is made for τ, errors in the inferred parameters quickly become unreasonable. A method for fitting single-injection data to the Michaelis-Menten or Briggs-Haldane model to simultaneously evaluate KM, k2, ΔRH, and τ is described and validated with experimental data. All four of these parameters can be accurately inferred provided the reaction time constant (k2E/KM) is larger than 1/τ and the data include enzyme saturated conditions. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions

    Science.gov (United States)

    Mazzei, Luca; Ciurli, Stefano; Zambelli, Barbara

    2014-01-01

    Isothermal titration calorimetry (ITC) is a well-described technique that measures the heat released or absorbed during a chemical reaction, using it as an intrinsic probe to characterize virtually every chemical process. Nowadays, this technique is extensively applied to determine thermodynamic parameters of biomolecular binding equilibria. In addition, ITC has been demonstrated to be able of directly measuring kinetics and thermodynamic parameters (kcat, KM, ΔH) of enzymatic reactions, even though this application is still underexploited. As heat changes spontaneously occur during enzymatic catalysis, ITC does not require any modification or labeling of the system under analysis and can be performed in solution. Moreover, the method needs little amount of material. These properties make ITC an invaluable, powerful and unique tool to study enzyme kinetics in several applications, such as, for example, drug discovery. In this work an experimental ITC-based method to quantify kinetics and thermodynamics of enzymatic reactions is thoroughly described. This method is applied to determine kcat and KM of the enzymatic hydrolysis of urea by Canavalia ensiformis (jack bean) urease. Calculation of intrinsic molar enthalpy (ΔHint) of the reaction is performed. The values thus obtained are consistent with previous data reported in literature, demonstrating the reliability of the methodology. PMID:24747990

  20. Predicting proton titration in cationic micelle and bilayer environments

    Energy Technology Data Exchange (ETDEWEB)

    Morrow, Brian H.; Shen, Jana K. [Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland 21201 (United States); Eike, David M.; Murch, Bruce P.; Koenig, Peter H. [Computational Chemistry, Modeling and Simulation GCO, Procter and Gamble, Cincinnati, Ohio 45201 (United States)

    2014-08-28

    Knowledge of the protonation behavior of pH-sensitive molecules in micelles and bilayers has significant implications in consumer product development and biomedical applications. However, the calculation of pK{sub a}’s in such environments proves challenging using traditional structure-based calculations. Here we apply all-atom constant pH molecular dynamics with explicit ions and titratable water to calculate the pK{sub a} of a fatty acid molecule in a micelle of dodecyl trimethylammonium chloride and liquid as well as gel-phase bilayers of diethyl ester dimethylammonium chloride. Interestingly, the pK{sub a} of the fatty acid in the gel bilayer is 5.4, 0.4 units lower than that in the analogous liquid bilayer or micelle, despite the fact that the protonated carboxylic group is significantly more desolvated in the gel bilayer. This work illustrates the capability of all-atom constant pH molecular dynamics in capturing the delicate balance in the free energies of desolvation and Coulombic interactions. It also shows the importance of the explicit treatment of ions in sampling the protonation states. The ability to model dynamics of pH-responsive substrates in a bilayer environment is useful for improving fabric care products as well as our understanding of the side effects of anti-inflammatory drugs.

  1. Effect of a stirring process in an isothermal titration microcalorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Socorro, F.; Nuez, I. de la; Alvarez, L.; Rodriguez de Rivera, M

    2004-10-01

    In this paper, it is analysed the way in which the thermodynamic results obtained in an isothermal titration microcalorimeter, with continuous injection of a liquid and a variable mass are affected. Two aspects are presented, the first one refers to a variation in the baseline that takes place when the liquid mass is increased in the laboratory cell, this variation is due to the change in the thermal coupling between the stirrer and its contact with the thermostat. The second aspect is the analysis of the effect of the stirring process and the injection velocity on the homogenization of the remaining mixture in the laboratory cell. The aim of the study of these two previous aspects is to increase the accuracy of the thermodynamic measures carried out. The variation of the baseline affects in a percentage from 1 to 2% of the total energy developed. It is also shown the necessity of a stirring process according to the injection velocity in order to obtain a homogeneous mixture at every instant. This fact allows to carry out a deconvolution of the calorimetric signal and to obtain directly the power developed in the mixture process in terms of the amount of mixed substance [Meas. Sci. Technol. 1 (1990) pp. 1285-1290; J. Thermal Analysis 41 (1994) pp. 1385-1392].

  2. Survey of the year 2008: applications of isothermal titration calorimetry.

    Science.gov (United States)

    Falconer, Robert J; Penkova, Anita; Jelesarov, Ilian; Collins, Brett M

    2010-01-01

    Isothermal titration calorimetry (ITC) is a fast, accurate and label-free method for measuring the thermodynamics and binding affinities of molecular associations in solution. Because the method will measure any reaction that results in a heat change, it is applicable to many different fields of research from biomolecular science, to drug design and materials engineering, and can be used to measure binding events between essentially any type of biological or chemical ligand. ITC is the only method that can directly measure binding energetics including Gibbs free energy, enthalpy, entropy and heat capacity changes. Not only binding thermodynamics but also catalytic reactions, conformational rearrangements, changes in protonation and molecular dissociations can be readily quantified by performing only a small number of ITC experiments. In this review, we highlight some of the particularly interesting reports from 2008 employing ITC, with a particular focus on protein interactions with other proteins, nucleic acids, lipids and drugs. As is tradition in these reviews we have not attempted a comprehensive analysis of all 500 papers using ITC, but emphasize those reports that particularly captured our interest and that included more thorough discussions we consider exemplify the power of the technique and might serve to inspire other users.

  3. 沉淀滴定的林邦滴定曲线方程%Ringbom titration curve equation of precipitation titration

    Institute of Scientific and Technical Information of China (English)

    乔成立; 李文新

    2014-01-01

    Ionic strength effect,acid effect,precipitation effect and ligand effect were identified as side reactions of the main reaction,Ringbom titration curve equation of precipitation titration was derived by means of material balance, conditional stability constant and titration scores,etc,which can lay a solid foundation for researching precipitation titration analysis theory on the basis of Ringbom titration curve equation.%把离子强度效应、酸效应、沉淀效应、配位效应等看作是主反应发生的副反应,通过物料平衡、条件稳定常数和滴定分数等推导出沉淀滴定的林邦滴定曲线方程,为用林邦滴定曲线方程研究沉淀滴定分析理论打下坚实的基础。

  4. Karl Gustaf Torsten Sjögren and the Sjögren-Larsson syndrome

    Directory of Open Access Journals (Sweden)

    Khalid Al Aboud

    2011-09-01

    Full Text Available Karl Gustaf Torsten Sjögren (1896-1974 a Swedish psychiatrist and geneticist, was a pioneer of modern Swedish psychiatry. Sjögren studied medicine at the University of Uppsala. From 1932 to 1935, he was Head Physician and Director of Lillehagen Hospital in Gothenburg, and between 1935- 1945, he was physician-in-chief at the psychiatric department of Sahlgrenska Hospital in Gothenburg. Sjögren was professor of psychiatry at Karolinska Institutet from 1945 to 1961 and was elected to the Royal Swedish Academy of Sciences in 1951. Sjögren was an expert of psychiatry for the World Health Organization. Among his many contributions to medicine, he is credited for describing several medical conditions, which were later named after him, including Graefe- Sjögren syndrome, Marinesco-Sjögren syndrome, and Sjögren-Larsson syndrome (SLS. During his work on juvenile amaurotic idiocy, Sjögren forged a collaboration with Tage K.L. Larsson, a statistics lecturer at the University of Lund. Their study on the combination of oligophrenia, congenital ichthyosis, and spastic disorders in 1957 established the clinical and genetic profile of a new disease entity, later known as Sjogren-Larsson syndrome (SLS.

  5. Karl Polanyi e a Nova Sociologia Económica: Notas sobre o conceito de (disembeddedness

    Directory of Open Access Journals (Sweden)

    Nuno Miguel Cardoso Machado

    2012-10-01

    Full Text Available No contexto da Nova Sociologia Económica, Karl Polanyi é quase consensualmente considerado o “pai” do conceito de incrustação (embeddedness. Todavia, este conceito foi alvo de uma apropriação selectiva por parte da disciplina, sendo negligenciada a sua relação com o restante edifício teórico construído por Polanyi. Pode, com efeito, falar‑se de uma “grande transformação” sofrida pelo conceito de incrustação: se em Polanyi ele está associado a um nível macro(económico e é utilizado para evidenciar o carácter excepcional da economia capitalista de mercado – que se encontra desincrustada da sociedade –, na NSE, por seu turno, é normalmente associado a um nível meso (e até micro, sendo preconizado que todas as economias – incluindo a capitalista – estão incrustadas.

  6. [Karl Jaspers. 100 years of “Allgemeine Psychopathologie” (General Psychopathology)].

    Science.gov (United States)

    Häfner, H

    2013-11-01

    With his "Allgemeine Psychopathologie" (general psychopathology) published in 1913, Karl Jaspers laid a comprehensive methodological and systematic foundation in psychiatry. Following Edmund Husserl, the founder of philosophical phenomenology, Jaspers introduced "static understanding" into psychopathology, i.e. the unprejudiced reproduction of conscious phenomena. From the philosopher Wilhelm Dilthey he further adopted the distinction between causal understanding as a means of accessing nature and pathological processes and hermeneutic understanding, also called genetic understanding, as a way of accessing mental phenomena. The intrusion of an event that is incomprehensible in terms of an understandable development is seen as indicating an extraconscious phenomenon or transition to a somatic process. Jaspers opted for philosophy early in his life. After quitting law studies he graduated in medicine, arrived in psychopathology without any psychiatric training, to psychology without ever studying psychology and to a chair in philosophy without a degree in philosophy. Despite believing himself to be chronically ill and to die early, Jaspers produced a life’s work almost immeasurable in scope. He died in 1969 aged 86 years.

  7. COLDz: Karl G. Jansky Very Large Array discovery of a gas-rich galaxy in COSMOS

    CERN Document Server

    Lentati, L; Carilli, C L; Riechers, D; Capak, P; Walter, F; Aravena, M; da Cunha, E; Hodge, J A; Ivison, R J; Smail, I; Sharon, C; Daddi, E; Decarli, R; Dickinson, M; Sargent, M; Scoville, N; Smolcic, V

    2014-01-01

    The broad spectral bandwidth at mm and cm-wavelengths provided by the recent upgrades to the Karl G. Jansky Very Large Array (VLA) has made it possible to conduct unbiased searches for molecular CO line emission at redshifts, z > 1.31. We present the discovery of a gas-rich, star-forming galaxy at z = 2.48, through the detection of CO(1-0) line emission in the COLDz survey, through a sensitive, Ka-band (31 to 39 GHz) VLA survey of a 6.5 square arcminute region of the COSMOS field. We argue that the broad line (FWHM ~570 +/- 80 km/s) is most likely to be CO(1-0) at z=2.48, as the integrated emission is spatially coincident with an infrared-detected galaxy with a photometric redshift estimate of z = 3.2 +/- 0.4. The CO(1-0) line luminosity is L'_CO = (2.2 +/- 0.3) x 10^{10} K km/s pc^2, suggesting a cold molecular gas mass of M_gas ~ (2 - 8)x10^{10}M_solar depending on the assumed value of the molecular gas mass to CO luminosity ratio alpha_CO. The estimated infrared luminosity from the (rest-frame) far-infrare...

  8. Ivan Karamazov’s rebellion in Albert Camus’ and Karl Jaspers’ interpretations

    Directory of Open Access Journals (Sweden)

    Urszula Lisowska

    2010-12-01

    Full Text Available The aim of this study is to present Albert Camus’ and Karl Jaspers’ interpretations of Ivan Karamazov’s rebellion as the diagnoses of the weakness of the human intellect in confrontation with the world and the criticism of rationalism. Therefore, in the introduction I will present those fragments of the novel that characterize Ivan’s rebellion as highly abstract and theoretical. At the same time, this common literary context serves as the ground for reconstruction and comparison of the basic philosophical assumptions of each author. The intention of the remaining part of the paper is, firstly, to reconstruct A. Camus’ and K. Jaspers’ epistemology and, secondly, to analyse the arguments against Ivan’s attitude formulated by the writers. Their criticisms of the protagonist’s excessive trust in intellect is based on their own concepts of human epistemic capacity, which are related to the problems of the absurd in A. Camus’ and transcendence in K. Jaspers’ writings. The question of nihilism demands analysis of A. Camus’ idea of the nature of rebellion as both affirmative and negative, and of K. Jaspers’ notion of faith as pre-intellectual trust. Finally, their criticisms of the slogan “If there is no God, then anything is allowed” introduces the problem of freedom, which allows the comparison of the concepts of solidarity (A. Camus and communication (K. Jaspers. In the conclusion these two philosophical attitudes are discussed together. Keywords: ; ; ; ; ; ; ; ;

  9. Karl Ove Knausgård’s My Struggle and the Serial Self

    Directory of Open Access Journals (Sweden)

    Inge van de Ven

    2016-06-01

    Full Text Available This article analyzes Karl Ove Knausgård’s six-volume autobiography My Struggle in the frame of an emerging cross-medial aesthetics of the ‘serial self’. This aesthetics is informed by the technological potentialities of digital media, and by social media practices like taking a selfie or posting a blog every single day and accumulating these self-representations, without selection. The serial self is marked by continuity, real-time effects, open-endedness, rhythm, repetition, and a thematic attention to the mundane. It can be discerned in the daily comic strip, the daily selfie, and time-lapse cinema. The article embeds My Struggle in this larger, intermedial framework. Moreover, it refers to the work of psychologist Galen Strawson to argue that the self-representations in Knausgård’s work should be understood as episodic rather than diachronic in nature. This results in a sequential and paratactic, rather than causal and hierarchical, presentation of memorial material. It is claimed that serial self-representations of this type are increasingly central to our current media ecology. They offer a valuable medium for investigating, materializing, and mapping on the page the traces left by the passage of time, as serialization lends itself to performative and cumulative representations of a ‘self’ in flux, that dramatize and perform the struggles of the episodic personality in search for continuity.

  10. Karl R. Popper’ın Tarihsicilik Eleştirisi

    Directory of Open Access Journals (Sweden)

    Rıza Bakış

    2016-06-01

    Full Text Available Karl R. Popper XX. yüzyılın önemli bir bilim felsefecisidir ve bu alandaki temel savı yanlışlamacılık kuramı olarak bilinmektedir. Fakat düşüncesinin bütün uzanımlarında kendini ele veren ve onun sistemini oluşturan ise esasında eleştirel akılcılık kuramıdır. Tarihsicilik eleştirisi de bunlarla sistematik bağlamda ilintili olarak toplum ve siyaset felsefesi konusundaki görüşlerini ihtiva etmektedir. Birey olarak insanı merkeze alan Popper’ın, tarihsicilik konusundaki düşüncelerini Platon, Aristoteles, Marx ve Hegel gibi büyük sistem kurucu düşünürler üzerinden somutlaştırdığı, bütüncü yapılara karşı birtakım eleştiriler getirdiği görülmektedir. Biz bu makalemizde Popper’ın tarihsicilik eleştirisini özellikle Platon, Aristoteles, Hegel ve Karx’la ilintili eleştirilerini ele alıp tartıştık.

  11. Rheumatoid arthritis is caused by Proteus: the molecular mimicry theory and Karl Popper.

    Science.gov (United States)

    Ebringer, Alan; Rashid, Tasha

    2009-06-01

    Rheumatoid arthritis is a crippling and disabling joint disease affecting over 20 million people. It occurs predominantly in women and smokers, and affects the HLA-DR1/4 individuals who carry the "shared epitope" of amino acids EQRRAA. The cause of this disease was investigated by the methods of the philosopher of science Karl Popper who suggested that scientific research should be based on bold conjectures and critical refutations. The "Popper sequences" generate new facts which then change or alter the original problem. The new facts must then be explained by any new theory. Using the "molecular mimicry" model, it was found that Proteus bacteria possess an amino acid sequence ESRRAL in haemolysin which resembles the, shared epitope, and another sequence in urease which resembles type XI collagen. Antibodies to Proteus bacteria have been found in 14 different countries. It would appear that rheumatoid arthritis is caused by an upper urinary tract infection by Proteus bacteria. Anti-Proteus therapy should be assessed in the management of this disease separately or in conjunction with existing modalities of therapy.

  12. Sir Karl Popper (1902-1994): in memoriam, 15 years later.

    Science.gov (United States)

    Notturno, Mark Amadeus

    2009-12-01

    September 17th, 2009 marks the 15th anniversary of Sir Karl Popper's death. Popper was an outspoken champion of critical rationalism, and a constant critic of authoritarian tendencies in science and society. He was also one of the spiritual founders of this journal and served on its first editorial advisory board. Popper was recognized around the world as one of the 20th century's greatest philosophers of science and one of its most articulate and influential critics of Marxism and closed society. When he died, the contemporary wisdom among professional philosophers was that his philosophy was generally right-but somehow obsolete. Some commentators said that it was now obvious that scientific theories cannot be shown to be true. Others said that we had witnessed the end of history and that his critique of closed societies, while no doubt important in its day, had been fully assimilated into Western thinking and still had meaning, if at all, only for the democracies in transition that were trying to emerge from the former Soviet Union. But 15 years after his death, a look at science and society around the world gives us good reason to remember his philosophy.

  13. [Note on the epistemology of clinical pharmacology: comparison with the approach of Karl Popper].

    Science.gov (United States)

    Boissel, J P

    1999-01-01

    Is clinical pharmacology a science or only an application of science? Karl Popper suggested a method to identify science and to sort it out from other logical activities such as metaphysics, whereby the falsification criterion he proposed can apply to the theory in such a way that the theory could be refuted. The clinical pharmacologist's approach requires the build-up of a therapeutic model on the basis of two other models: the physiopathologic and the pharmacological. The three-model construct is a theory. Is it scientific in the Popperian sense? From the therapeutic model, one can predict the efficacy of a drug, and the corresponding statement is tested by a clinical trial. Whatever the original statement, it is modified into a refutable one because of the use of the statistical approach in clinical trials. Furthermore, the predicate represents a hypothesis of the model validity, which will then be confronted with 'reality' through clinical experiment. As the therapeutic model is refutable, clinical pharmacology is a science in the Popperian sense.

  14. Karl Popper versus Theodor Adorno: lições de um confronto histórico

    Directory of Open Access Journals (Sweden)

    Angela Ganem

    2012-03-01

    Full Text Available Karl Popper versus Theodor Adorno: Lessons from a historical confrontation. In 1961, during the Congress of the German Society of Sociology, two great theoretical references of the XX century faced in a historical debate about the logic of the social sciences. In addition to methodological issues strict sense, the confrontation became known as a debate between positivism and dialectic. The article first deals with the theoretical trajectories of Popper and Adorno and the relation of their theories with their political and ideological certainties. On one hand, the trajectory of the Popperian epistemology is examined, its contributions and vigorous attacks on Marx in what he called 'poverty of historicism" and false predictive Marxist world, and, on the other hand, the role of Adorno in the Frankfurt School, his criticism of totalitarianism and the defense of a critical emancipatory reason. The article also deals with the confrontation itself, the exposure of Popper's twenty-seven theses that culminate with the situation logic and the method of the economy as exemplary for the social sciences and Adorno's critical perspective of sociology and society as non-separable objects. In conclusion we show how the articulation of theory with the weltanschauung of each author helps to clarify the terms of the debate and how the confrontation contributed unequivocally to the dynamics of scientific progress and for the critical history of the ideas.

  15. A Historical Survey of Sir Karl Popper's Contribution to Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    William M. Shields

    2012-11-01

    Full Text Available Sir Karl Popper (1902-1994, though not trained as a physicist and embarrassed early in his career by a physics error pointed out by Einstein and Bohr, ultimately made substantial contributions to the interpretation of quantum mechanics. As was often the case, Popper initially formulated his position by criticizing the views of others - in this case Niels Bohr and Werner Heisenberg. Underlying Popper's criticism was his belief that, first, the Copenhagen interpretation of quantum mechanics abandoned scientific realism and second, the assertion that quantum theory was complete (an assertion rejected by Einstein among others amounted to an unfalsifiable claim. Popper insisted that the most basic predictions of quantum mechanics should continue to be tested, with an eye towards falsification rather than mere adding of decimal places to confirmatory experiments. His persistent attacks on the Copenhagen interpretation were aimed not at the uncertainty principle itself and the formalism from which it was derived, but at the acceptance by physicists of an unclear epistemology and ontology that left critical questions unanswered.Quanta 2012; 1: 1–12.

  16. Philosophy and Theology in Karl Barth’s Neo-Orthodoxy

    Directory of Open Access Journals (Sweden)

    Pylaev Maksim

    2016-12-01

    Full Text Available In the proposed article the author explores the concept of God’s Word in theocentric theology of K. Barth and theology of early K. Barth in times of the second edition of 'Romans’, in terms of their philosophy founding. The author compares the block of philosophical and theological topics such as the theory of temporality, dialectic concept of the beginning (Ursprung and other types in philosophical discourses used by K. Barth (platonism, neo-Kantianism, existentialism, scholasticism, phenomenological philosophy and others with theology of K. Barth. The article gives a brief reconstruction of the theology of God’s Word by K. Barth in its two complementary projections as presented in the ‘Sketch of Christian Doctrine’ and ‘Dogma of the Church’. During the presentation the reader is well acquainted with the third projection of the concept of God’s Word by K. Barth at the time of the genesis of the book ‘Fides quaerens intellectum’. The article tests the hypothesis that the second edition of the ‘Romans’, ‘Fides quaerens intellectum’ and ‘Sketch of the Christian Dogma’ with ‘Church Dogma’ explicate the form of Christian theology, which, absorbing primarily the important philosophic achievements of 19–20th centuries, yet tries to stay free of them. Using various forms of philosophical discourses Karl Barth implements his own task of building a Christian theology beyond metaphysics, history and human existence.

  17. Prison break: Karl Menninger's The Crime of Punishment and its reception in U.S. psychology.

    Science.gov (United States)

    Devonis, David C; Triggs, Jessica

    2017-02-01

    In 1968, Karl Menninger, a highly visible and vocal U.S. psychiatrist, published a call to action on prison reform, The Crime of Punishment (Menninger, 1966/1968). This widely circulated book's central idea is that punishment as practiced in penal settings is an injustice amounting to a crime. At the outset, The Crime of Punishment quickly achieved national attention. Within mainstream psychology, its antipunishment message encountered a changed climate in which punishment, thought ineffective during the period 1930 through 1960, was redefined as an effective component in learning. It also met competition from the contemporaneous Stanford Prison Experiment (Haney, Banks, & Zimbardo, 1973), which quickly rose to equivalent media presence and superior disciplinary prominence. Both the Stanford Prison Experiment and The Crime of Punishment survived in the antireform era of hyperincarceration after 1974 as parallel examples of reform activism, one secular and one religious in character, illustrating some convergences of aim between psychology and psychiatry outside of specifically clinical issues. (PsycINFO Database Record

  18. Karl Barth’s male-female order: A kingpin of dogmatic disparity

    Directory of Open Access Journals (Sweden)

    Yolanda Dreyer

    2007-05-01

    Full Text Available Karl Barth’s gender perspective is often analysed with reference to his so-called “theoethics” or “creational theology”. This perspective perpetuates an asymmetry in gender relations that was prevalent in Biblical times, throughout Christianity and to some extent still is visible today. He based his view on the subordination of women on an exegesis of Genesis 1:27 as “intertext” of Ephesians 5:22-23. Barth’s asymmetrical gender perspective is a product of his embedment in Western Christian tradition which in turn, is rooted in early Christian patriarchal theology. The aim of this article is to focus on Barth’s ontological reframing of the traditional understanding of the Biblical notion of human beings as created in the “image of God”. The article consists of four sections: (a Luther’s and Calvin’s gender perspectives; (b the Enlightenment failure to achieve emancipation; (c gender disparity in Reformed theology; and (d a feminist alternative.

  19. Karl R. Popper'ın Tarihsicilik Eleştirisi

    Directory of Open Access Journals (Sweden)

    Yrd.Doç.Dr. Rıza Bakış

    2016-06-01

    Full Text Available Karl R. Popper XX. yüzyılın önemli bir bilim felsefecisidir ve bu alandaki temel savı yanlışlamacılık kuramı olarak bilinmektedir. Fakat düşüncesinin bütün uzanımlarında kendini ele veren ve onun sistemini oluşturan ise esasında eleştirel akılcılık kuramıdır. Tarihsicilik eleştirisi de bunlarla sistematik bağlamda ilintili olarak toplum ve siyaset felsefesi konusundaki görüşlerini ihtiva etmektedir. Birey olarak insanı merkeze alan Popper’ın, tarihsicilik konusundaki düşüncelerini Platon, Aristoteles, Marx ve Hegel gibi büyük sistem kurucu düşünürler üzerinden somutlaştırdığı, bütüncü yapılara karşı birtakım eleştiriler getirdiği görülmektedir. Biz bu makalemizde Popper’ın tarihsicilik eleştirisini özellikle Platon, Aristoteles, Hegel ve Karx’la ilintili eleştirilerini ele alıp tartıştık.

  20. Early East Asian art history in Vienna and its trajectories: Josef Strzygowski, Karl With, Alfred Salmony

    Directory of Open Access Journals (Sweden)

    Julia Orell

    2015-12-01

    Full Text Available In 1912 Josef Strzygowski founded the ‘Section for East Asian Art History’ at the University of Vienna, which attracted many students who would continue their careers in museums and at universities and thus established East Asian art history as an academic field. This paper examines these early art historical engagements with East Asian art: First, I discuss the role of East Asian art in Strzygowski’s agenda of broadening art history’s geographical scope beyond Europe and in his argument about the dominance of ‘Nordic’ artistic traditions in Europe and in Asia. Secondly, I introduce the work of two early students at the ‘Section for East Asian Art History’ in Vienna, Karl With and Alfred Salmony. Their respective approaches to East Asian art exemplify a range of methodological concerns of their time, from stylistic narratives, the concept of ars una, comparative frameworks, to ideas about cultural or national ‘purity’ in the arts, and an interest in cross-cultural adaption and transformation of motifs and symbolism.

  1. A dialética expositiva de "O Capital" de Karl Marx

    Directory of Open Access Journals (Sweden)

    Carlos Prado

    2009-09-01

    Full Text Available

    Este artigo tem o objetivo de analisar a forma expositiva dialética de O Capital de Karl Marx. O modo de exposição utilizado por Marx segue a tradição dialética e ascende do abstrato ao concreto, da aparência para a essência. Começa no nível mais simples e vazio de conteúdo para aos poucos ir desenvolvendo as contradições, acrescentando as determinações políticas, econômicas e sociais, para assim desvelar a essência por trás das formas aparentes.

  2. Synthèse de Fischer Tropsch sur support conducteur à base de carbure de silicium

    OpenAIRE

    Tymowski, Benoît de

    2012-01-01

    The Fischer-Tropsch synthesis (FTS) allows the transformation of a mixture of synthesis gas, i.e. H2 and CO, into valuable liquid hydrocarbons. The catalysts generally used in FTS are based on iron or cobalt supported on alumina or silica. ln the present work, silicon carbide (SiC) has been proposed as a replacement media to traditional supports. The results obtained indicate that the mesoporous SiC containing cobalt catalyst exhibits a good FTS activity and an extremely high selectivity towa...

  3. A "cousin" of a theorem of Cs\\'aki and Fischer

    OpenAIRE

    Bradley, Richard C.

    2016-01-01

    A 1963 theorem of P. Cs\\'aki and J. Fischer deals with the "maximal correlation coefficient" in the context of independent pairs of $\\sigma$-fields on a probability space. Here a somewhat restricted "cousin" of their result is presented for the same context, but involving in part an analogous measure of dependence based only on correlations of indicator functions. It was first proved by the author in an unpublished 1978 Ph.D. thesis. An example is constructed to show a limitation of this "cou...

  4. Recent Technological Developments in Cobalt Catalysts for Fischer-Tropsch Synthesis

    Institute of Scientific and Technical Information of China (English)

    Junling Zhang; Jiangang Chen; Yongwang Li; Yuhan Sun

    2002-01-01

    Co-based catalysts are often utilized due to their high Fischer-Tropsch synthesis (FT) activity,C+5 hydrocarbon selectivity, low water-gas shift reaction (WGS) activity and relatively low cost. Selective control of C5+ hydrocarbons and the catalyst longevity are critical in the design of cobalt catalysts.Thus, various methods to improve the performance of Co catalysts have been suggested. The progress in cobalt catalysts reviewed in the last few decades, mainly involved the support, promoter, preparation and deactivation of Co-based catalysts.

  5. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Yates, I.C.; Satterfield, C.N.

    1989-01-01

    The rate of synthesis gas consumption over a cobalt FischerTropsch catalyst was measured in a well-mixed, continuous-flow, slurry reactor at 220 to 240[degrees]C, 0.5 to 1.5 MPa, H[sub 2]/CO feed ratios of 1.5 to 3.5 and conversions of 7 to 68% of hydrogen and 11 to 73% of carbon monoxide. The inhibiting effect of carbon monoxide was determined quantitatively and a Langmuir-Hinshelwood-type equation of the following form was found to best represent the results: -R[sub H[sub 2+Co

  6. Macromolecules and Enzymes: The Geneva Heritage from Kurt H. Meyer and Edmond H. Fischer.

    Science.gov (United States)

    Fischer, Edmond H; Piguet, Alfred

    2009-12-01

    On the 26th May 2009, Edmond Fischer, winner with Ed Krebs of the Nobel prize in physiology or medicine in 1992, and his colleague at the time of his research activities at the Ecole de chimie of the University of Geneva, Alfred Piguet, met with Andreas Hauser, Claude Piguet and Howard Riezman of the Section de chimie et biochimie of the University of Geneva to talk about how they became scientists under the impetus of Kurt H. Meyer and what became of them thereafter.

  7. Fundaments of Quaternionic Clifford Analysis III: Fischer Decomposition in Symplectic Harmonic Analysis

    OpenAIRE

    Brackx, Fred; De Schepper, Hennie; Eelbode, David; Lavicka, Roman; Soucek, Vladimir

    2014-01-01

    In the framework of quaternionic Clifford analysis in Euclidean space $\\mathbb{R}^{4p}$, which constitutes a refinement of Euclidean and Hermitian Clifford analysis, the Fischer decomposition of the space of complex valued polynomials is obtained in terms of spaces of so--called (adjoint) symplectic spherical harmonics, which are irreducible modules for the symplectic group Sp$(p)$. Its Howe dual partner is determined to be $\\mathfrak{sl}(2,\\mathbb{C}) \\oplus \\mathfrak{sl}(2,\\mathbb{C}) = \\ma...

  8. Study on the Precursor Phase Composition of Fused Iron Catalyst for Fischer-Tropsch Synthesis

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The effect of the precursor composition of fused iron catalyst on the performance of Fischer-Tropsch synthesis was investigated. XRD, BET and CO2 adsorption experiments were carried out to provide better insight into the relationship therein. The results showed that the selectivity of C5+ hydrocarbon products was dependent on the mole ratio of Fe2+/Fe3+, which was represented by a hump-shaped curve. Catalysts with precursors containing Fe3O4 phase favored the magnetite spinal formation during F-T reaction, while Fe1-xO-based catalysts were more likely to favor the formation and growth of the iron carbide crystals.

  9. Titration Calorimetry Applied to the Thermokinetics Study of Consecutive First-order Reactions

    Institute of Scientific and Technical Information of China (English)

    SHI Jing-Yan; LI Jie; WANG Zhi-Yong; LIU Yu-Wen; WANG Cun-Xin

    2008-01-01

    The thermokinetic mathematical models for consecutive first-order reactions in titration period and the stopped-titration reaction period were proposed for titration calorimetry, based on which, thermodynamic parameters (reaction enthalpies, △rHm1 and △rHm2) and kinetic parameters (rate constants, k1 and k2) of the consecutive first-order reactions could be obtained by directly simulating the calorimetric curve from a single experiment with the method of nonlinear least squares regression (NLLS).The reliability of the model has been verified by investigating the reaction of the saponification of diethyl succinate in an aqueous ethanol solvent.

  10. On the Physical Meaning of the Isothermal Titration Calorimetry Measurements in Calorimeters with Full Cells

    Science.gov (United States)

    Grolier, Jean-Pierre E.; del Río, Jose Manuel

    2009-01-01

    We have performed a detailed study of the thermodynamics of the titration process in an isothermal titration calorimeter with full cells. We show that the relationship between the enthalpy and the heat measured is better described in terms of the equation Δ H = Winj + Q (where Winj is the work necessary to carry out the titration) than in terms of ΔH = Q. Moreover, we show that the heat of interaction between two components is related to the partial enthalpy of interaction at infinite dilution of the titrant component, as well as to its partial volume of interaction at infinite dilution. PMID:20054472

  11. Synthesis of donor-acceptor alkynylcyclopropanes by diastereoselective cyclopropanation of electron-deficient alkenes with alkoxyalkynyl Fischer carbene complexes.

    Science.gov (United States)

    Barluenga, José; Fernández-Rodríguez, Manuel A; García-García, Patricia; Aguilar, Enrique; Merino, Isabel

    2005-12-16

    The reaction of electron-deficient alkenes with alkoxyalkynyl Fischer carbene complexes (FCCs) represents a straightforward route to a new type of captodative (donor-acceptor) alkynylcyclopropanes, which have been prepared in moderate to high yields and in a diastereoselective manner. Some studies regarding the employment of additives to facilitate the recovery of the metal moiety after the reaction are also described. Finally, the first example of a cyclopropanation reaction through employing Fischer carbene complexes under microwave irradiation is presented; this method proved to be an advantageous alternative to the thermal reaction.

  12. Isothermal titration calorimetry in nanoliter droplets with subsecond time constants.

    Science.gov (United States)

    Lubbers, Brad; Baudenbacher, Franz

    2011-10-15

    We reduced the reaction volume in microfabricated suspended-membrane titration calorimeters to nanoliter droplets and improved the sensitivities to below a nanowatt with time constants of around 100 ms. The device performance was characterized using exothermic acid-base neutralizations and a detailed numerical model. The finite element based numerical model allowed us to determine the sensitivities within 1% and the temporal dynamics of the temperature rise in neutralization reactions as a function of droplet size. The model was used to determine the optimum calorimeter design (membrane size and thickness, junction area, and thermopile thickness) and sensitivities for sample volumes of 1 nL for silicon nitride and polymer membranes. We obtained a maximum sensitivity of 153 pW/(Hz)(1/2) for a 1 μm SiN membrane and 79 pW/(Hz)(1/2) for a 1 μm polymer membrane. The time constant of the calorimeter system was determined experimentally using a pulsed laser to increase the temperature of nanoliter sample volumes. For a 2.5 nanoliter sample volume, we experimentally determined a noise equivalent power of 500 pW/(Hz)(1/2) and a 1/e time constant of 110 ms for a modified commercially available infrared sensor with a thin-film thermopile. Furthermore, we demonstrated detection of 1.4 nJ reaction energies from injection of 25 pL of 1 mM HCl into a 2.5 nL droplet of 1 mM NaOH.

  13. 混合离子的沉淀准确滴定%Precipitation Titration for Multiple Ions

    Institute of Scientific and Technical Information of China (English)

    乔成立

    2016-01-01

    The absolute value of titration break in precipitation titration is deduced with the Ringbom titration curve equation, and the conditions for accurate precipitation titration are thus deduced with the absolute value of the titration break.%用沉淀滴定的林邦滴定曲线方程推导滴定突跃的绝对值,用滴定突跃的绝对值推导混合离子准确滴定的条件。

  14. Co-Zn-Al based hydrotalcites as catalysts for Fischer-Tropsch process

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, C.L.; Pirola, C.; Boffito, D.C.; Di Fronzo, A. [Univ. degli Studi di Milano (Italy). Dipt. di Chimica Fisica ed Elettrochimica; Di Michele, A. [Univ. degli Studi di Perugia (Italy). Dipt. di Fisica; Vivani, R.; Nocchetti, M.; Bastianini, M.; Gatto, S. [Univ. degli Studi di Perugia (Italy). Dipt. di Chimica

    2011-07-01

    Co-Zn-Al based hydrotalcites have been investigated as catalysts for the well-known Fischer- Tropsch synthesis. A series of ternary hydrotalcites in nitrate form was prepared with the urea method in order to obtain active catalysts for the above mentioned process. The thermal activation at 350 C gives raise to finely dispersed metallic Co on the mixed oxides, so resulting in retaining the metal distribution of the parent compounds. An optimization study concerning the amount of cobalt of the prepared catalysts (range 15-70% mol, metal based) and the reaction temperature (220-260 C) is reported. All the samples have been fully characterized (BET, ICP-OES, XRPD, TG-DTA, FT-IR, SEM and TEM) and tested in a laboratory pilot plant. Tests to evaluate the stability of these materials were carried out in stressed conditions concerning both the activation and the operating temperatures and pressures (up to 350 C and 2.0 MPa). The obtained results suggest the possibility of using synthetic hydrotalcites as suitable Co-based catalysts for the Fischer-Tropsch synthesis. (orig.)

  15. Effect of clutch surface changes on the computerized pantographic reproducibility index and the Fischer angle.

    Science.gov (United States)

    Dupas, P H; Picart, B; Graux, F; Lefevre, C

    1987-05-01

    This study of eight patients compared the pantographic numeric data obtained with a concave clutch with those obtained with a flat clutch. The slight alterations that resulted were insignificant and varied with each patient. The only difference between Depoorter's study and this one is the manual calculation of the EPRI compared with the computerized calculation of CPRI. Small variation was found in the value of the Fischer angle when the studies were compared. As shown in Depoorter's work, the shape of the clutch does not produce any significant changes in the recording of the posterior determinants. This conclusion is confirmed by this study for both the CPRI and the value of the Fischer angle. The concave clutch and the flat clutch reproduced similar results in both studies. By altering the central bearing pin and obtaining the same interclutch distance for both clutches, we obtained results in this study that refute the findings of Scortecci that a concave clutch was superior to a flat clutch.

  16. Development and process evaluation of improved Fischer-Tropsch slurry catalysts. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bukur, D.B.; Mukesh, D.; Patel, S.A.; Zimmerman, W.H.; Rosynek, M.P. [Texas A& M Univ., College Station, TX (United States); Kellogg, L.J. [Air Products and Chemicals, Inc., Allentown, PA (United States)

    1990-04-01

    This report describes results of a study aimed at developing and evaluating improved catalysts for a slurry Fischer-Tropsch (FT) process for converting synthesis gas to high quality transportation fuels (gasoline and distillate). The improvements in catalyst performance were sought by studying effects of pretreatment conditions, promoters and binders/supports. A total of 20 different, iron based, catalysts were evaluated in 58 fixed bed reactor tests and 10 slurry reactor tests. The major accomplishments and conclusions are summarized below. The pretreatment conditions (temperature, duration and the nature of reducing gas) have significant effect on catalyst performance (activity, selectivity and stability) during Fischer-Tropsch synthesis. One of precipitated unsupported catalysts had hydrocarbon selectivity similar to Mobil`s I-B catalyst in high wax mode operation, and had not experienced any loss in activity during 460 hours of testing under variable process conditions in a slurry reactor. The effect of promoters (copper and potassium) on catalyst performance during FT synthesis has been studied in a systematic way. It was found that potassium promotion increases activities of the FT and water-gas-shift (WGS) reactions, the average molecular weight of hydrocarbon products, and suppresses the olefin hydrogenation and isomerization reactions. The addition of binders/supports (silica or alumina) to precipitated Fe/Cu/K catalysts, decreased their activity but improved their stability and hydrocarbon selectivity. The performance of catalysts of this type was very promising and additional studies are recommended to evaluate their potential for use in commercial slurry reactors.

  17. Solid state NMR investigation of silica aerogel supported Fischer-Tropsch catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhiru; Dunn, Brian C.; Turpin, Gregory C.; Eyring, Edward M.; Ernst, Richard D.; Pugmire, Ronald J. [Department of Chemistry, University of Utah, Salt Lake City, UT 84112 (United States)

    2007-01-15

    The Fischer-Tropsch (F-T) catalyst is the critical component for the F-T synthesis of a variety of hydrocarbons from syngas. Fischer-Tropsch cobalt, iron and ruthenium catalysts supported on silica aerogel have been prepared using a combination of sol-gel chemistry and vapor phase deposition methods. Solid state NMR spectroscopy, a very powerful technique for analyzing the structure and dynamics of various materials, was employed in the study of these F-T catalyst systems. The silica aerogel supported F-T catalysts have been investigated using both solid state {sup 29}Si and {sup 13}C NMR methods. The silica aerogel's tetrahedral sub-unit structure and the influence of the loaded metal compounds have been observed. Three types of Si(O{sub 1/2}){sub 4} tetrahedral unit structure (Q{sub 2}, Q{sub 3} and Q{sub 4}) are clearly resolved in the silica aerogel samples. The calcining process and the loading of metal compounds produce line broadening in the {sup 29}Si spectra sufficient to prevent clear resolution of the three distinct Q{sub n} spectral lines, but the broadened spectra indicate that the three Q sub-unit structures are still present. The ferrocene and ruthenocene molecules used in the vapor phase deposition method exhibit a rapid exchange within the silica aerogel support similar to what one would expect in the gas or liquid state. (author)

  18. Fischer-Tropsch Synthesis on Multicomponent Catalysts: What Can We Learn from Computer Simulations?

    Directory of Open Access Journals (Sweden)

    José L. C. Fajín

    2015-01-01

    Full Text Available In this concise review paper, we will address recent studies based on the generalized-gradient approximation (GGA of the density functional theory (DFT and on the periodic slab approach devoted to the understanding of the Fischer-Tropsch synthesis process on transition metal catalysts. As it will be seen, this computational combination arises as a very adequate strategy for the study of the reaction mechanisms on transition metal surfaces under well-controlled conditions and allows separating the influence of different parameters, e.g., catalyst surface morphology and coverage, influence of co-adsorbates, among others, in the global catalytic processes. In fact, the computational studies can now compete with research employing modern experimental techniques since very efficient parallel computer codes and powerful computers enable the investigation of more realistic molecular systems in terms of size and composition and to explore the complexity of the potential energy surfaces connecting reactants, to intermediates, to products of reaction. In the case of the Fischer-Tropsch process, the calculations were used to complement experimental work and to clarify the reaction mechanisms on different catalyst models, as well as the influence of additional components and co-adsorbate species in catalyst activity and selectivity.

  19. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Chanenchuk, C.A.; Yates, I.C.; Satterfield, C.N.

    1990-01-01

    A Co/MgO/SiO[sub 2] Fischer-Tropsch catalyst was operated simultaneously with a Cu/ZnO/Al[sub 2]O[sub 3] water-gas-shift catalyst in a slurry reactor for over 400 hours. The process conditions were held constant at a temperature of 240[degrees]C, a pressure of 0.79 MPa, and a 1.1 H[sub 2]/CO feed of 0.065 Nl/min-g.cat. The Fischer-Tropsch activity remained constant at the level predicted by the operation of the Co/MgO/SiO[sub 2] catalyst alone. The water-gas-shift reaction was near equilibrium. The hydrocarbon product distribution of the combined catalyst system was stable and matched that of the CO/MgO/SiO[sub 2] operating alone under similar conditions. The combined catalyst system exhibited a high selectivity to n-alkanes. Neither catalysts's operation appeared to have a detrimental effect on that of the other, showing promise for future option.

  20. Synthesis in situ of gold nanoparticles by a dialkynyl Fischer carbene complex anchored to glass surfaces

    Science.gov (United States)

    Bertolino, María Candelaria; Granados, Alejandro Manuel

    2016-10-01

    In this work we present a detailed study of classic reactions such as "click reaction" and nucleophilic substitution reaction but on glass solid surface (slides). We used different reactive center of a dialkynylalcoxy Fischer carbene complex of tungsten(0) to be anchored to modified glass surface with amine, to obtain aminocarbene, and azide terminal groups. These cycloaddition reaction showed regioselectivity to internal triple bond of dialkynyl Fischer carbene complex without Cu(I) as catalyst. Anyway the carbene anchored was able to act as a reducing agent to produce in situ very stable gold nanoparticles fixed on surface. We showed the characterization of modified glasses by contact angle measurements and XPS. Synthesized nanoparticles were characterized by SEM, XPS, EDS and UV-vis. The modified glasses showed an important enhancement Raman-SERS. This simple, fast and robust method to create a polifunctional and hybrid surfaces can be valuable in a wide range of applications such as Raman-SERS substrates and other optical fields.

  1. Synthesis and catalytic properties of eggshell cobalt catalysts for the Fischer-Tropsch synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Iglesia, E. [Univ. of California, Berkeley, CA (United States); Soled, S.L.; Baumgartner, J.E. [Exxon Research and Engineering Co., Annandale, NJ (United States)] [and others

    1995-04-15

    CO diffusional restrictions decrease the rate and C{sup +}{sub 5} selectivity in large (1-3 mm) catalyst pellets required for Fischer-Tropsch synthesis in packed bed reactors. Eggshell catalysts, in which the active Co component is preferentially located near the outer pellet surface, decrease these transport restrictions and increase Fischer-Tropsch synthesis rates and C{sup +}{sub 5} selectivity. Maximum C{sup +}{sub 5} selectivities occur on catalysts with intermediate shell thickness, because these catalysts avoid intrapellet CO concentration gradients but still restrict the diffusive removal of reactive olefin products, which can readsorb and continue to grow to higher molecular weight hydrocarbons. Eggshell catalysts were prepared by a novel impregnation technique using molten cobalt nitrate. The eggshell thickness is controlled by the melt viscosity and by the contact time between the melt and the support pellet. These impregnation procedures and the slow reduction of the impregnated nitrate salts lead to relatively high cobalt dispersions (0.05-0.07) even at the high Co concentrations (40-50 wt%) present within the shell region. 51 refs., 8 figs., 4 tabs.

  2. Determination of arsenic(III), sulphite and sulphur dioxide using the triangle programmed coulometric titration principle

    Energy Technology Data Exchange (ETDEWEB)

    Buchholz, F.; Buschmann, N. (Muenster Univ. (Germany, F.R.))

    1990-11-01

    In 1975, Pungor et al. established a new method called Triangle Programmed Coulometric Titration, which allows to titrate flowing sample solutions. The following paper presents a new analytical procedure for the determination of sulphur dioxide based on this technique. To obtain this, sulphur dioxide was transferred across a semipermeable membrane from a gaseous phase into an aqueous acceptor phase. Then the SO{sub 2}-concentration of the streaming aqueous phase was analysed bromometrically using the Triangle Programmed Coulometric Titration principle. The titration curves were followed continuously by an AC-bivoltammetric flow-through detector. Using this procedure a determination of SO{sub 2} concentrations between 400 and 2500 mg/m{sup 3} was possible.(orig.).

  3. Simple home-made sensors for potentiometric titrations. [Nitroform CH(NO/sub 2/)/sub 3/

    Energy Technology Data Exchange (ETDEWEB)

    Selig, W.

    1982-04-01

    A sensor for potentiometric titrations was prepared by coating a spectroscopic graphite rod with a solution of poly(vinyl chloride) and dioctyphthalate in tetrahydrofuran. The reference electrode was an Ag/AgCl single-junction electrode. The sensor was used in precipitation, acid-base, compleximetric, and redox titrations. Preparation of the coated-graphite sensor is simple and rapid. Moreover, it is quite inexpensive. A limitation is its applicability in aqueous media only, because organic solvents will dissolve the membrane. Various uncoated types of graphite have also been investigated as sensors, particularly in two applications of interest in the analysis of propellants: the titration of nitroform and perchlorate. Obviously, these sensors can be used also in nonaqueous, or partially nonaqueous media. These sensors may also find use in the potentiometric titration of fluoride vs La(III) or Th(IV).

  4. Opuntia ficus indica (L.) Fruit Extract as Natural Indicator in Acid-Base Titration

    OpenAIRE

    Manoj A. Suva

    2014-01-01

    In routine experiments synthetic indicators are the choice of acid base titrations. But there are some limitations like environmental pollution, availability and higher cost which leads to search for natural compounds as an acid base indicator was started. The present work highlights theexploit of the methanolic and aqueous extract of the fruit of Opuntia ficus indica plants as a natural acid base indicator in acid base titrations. Opuntia ficus indica plant was identified and fruits were was...

  5. The Softening of Hard Water and Complexometric Titrations. An Undergraduate Experiment

    Science.gov (United States)

    Ceretti, Helena; Hughes, Enrique A.; Zalts, Anita

    1999-10-01

    A 2-hour experiment for undergraduates is presented in which (i) water hardness is explained and demonstrated; (ii) ion-exchange resin properties are visually demonstrated and then used for softening water; (iii) complexometric titrations are used for evaluating water hardness before and after softening; and (iv) acid-base titration can be used to show that the Ca/Mg ions removed by the ion exchanger are replaced by H ions.

  6. [The Roots of Idiographic Paleontology: Karl Alfred von Zittel's Methodology and Conception of the Fossil Record].

    Science.gov (United States)

    Tamborini, Marco

    2015-12-01

    This paper examines Karl Alfred von Zittel’s practice in order to uncover the roots of so-called idiographic paleontology.The great American paleontologist Stephen Jay Gould (1941–2002) defined the discipline of idiographic paleontology as illustration and description of the morphological features of extinct species. However, this approach does not investigate macroevolutionary patterns and processes. On the contrary, the paleobiological revolution of the 1970s implemented an epistemic methodology that illustrates macrovelutionary patterns and laws by combining idiographic data with a nomothetic form of explanation. This article elucidates the features of the idiographic data as well as the acquired knowledge coupled with this approach. First of all, Heinrich G. Bronn’s (1800–1862) statistical method is analyzed. Zittel’s practice arose as a reaction against the approximate conclusions reached by Bronn’s quantitative approach. Second, the details of Zittel’s methodology are described in order to bring out its peculiarities.The microscope played a pivotal role in creating and forming Zittel’s morphological data. This analysis sheds new light on the reasons behind the so-called ideographic paleontology, thus revising Gould’s historical reconstruction, as well as on the notion of paleontological data. However, even though Zittel aimed at reaching precise and stable conclusions,his data cannot be used for elucidating evolutionary mechanisms: they are scientific in a purely descriptive sense, but completely useless for biological investigations. Finally, this paper examines how Zittel’s methodology affects the contemporary paleobiological enterprise and thereby reflects upon the notion of natural history.

  7. Evaluation of Karl Storz CMAC Tip™ device versus traditional airway suction in a cadaver model.

    Science.gov (United States)

    Lipe, Demis N; Lindstrom, Randi; Tauferner, Dustin; Mitchell, Christopher; Moffett, Peter

    2014-07-01

    We compared the efficacy of Karl Storz CMAC Tip™ with inline suction to CMAC with traditional suction device in cadaveric models simulating difficult airways, using media mimicking pulmonary edema and vomit. This was a prospective, cohort study in which we invited emergency medicine faculty and residents to participate. Each participant intubated 2 cadavers (one with simulated pulmonary edema and one with simulated vomit), using CMAC with inline suction and CMAC with traditional suction. Thirty emergency medicine providers performed 4 total intubations each in a crossover trial comparing the CMAC with inline suction and CMAC with traditional suction. Two intubations were performed with simulated vomit and two with simulated pulmonary edema. The primary outcome was time to successful intubation; and the secondary outcome was proportion of successful intubation. The median time to successful intubation using the CMAC with inline suction versus traditional suction in the pulmonary edema group was 29s and 30s respectively (p=0.54). In the vomit simulation, the median time to successful intubation was 40s using the CMAC with inline suction and 41s using the CMAC with traditional suction (p=0.70). There were no significant differences in time to successful intubation between the 2 devices. Similarly, the proportions of successful intubation were also not statistically significant between the 2 devices. The proportions of successful intubations using the inline suction were 96.7% and 73.3%, for the pulmonary edema and vomit groups, respectively. Additionally using the handheld suction device, the proportions for the pulmonary edema and vomit group were 100% and 66.7%, respectively. CMAC with inline suction was no different than CMAC with traditional suction and was associated with no statistically significant differences in median time to intubation or proportion of successful intubations.

  8. Metagabbro associated with the shear zone on Prins Karls Forland (Svalbard, Arctic)

    Science.gov (United States)

    Maraszewska, Maria; Manecki, Maciej; Czerny, Jerzy; Schneider, David; Myhre, Per Inge; Faehnrich, Karol; Barnes, Christopher

    2016-04-01

    Prins Karls Forland (PKF) is a N-S elongated island situated west of Spitsbergen in the Svalbard archipelago, High Arctic. The northern part of the island is dominated by siliciclastic metasediments regionally metamorphosed to greenshist facies assemblages during one distinct stage of tectonism. Amphibolite facies garnet-mica schists, mica schists, quartzites and carbonate-silicate rocks exhibiting evidence of at least two distinct, strong deformation episodes (including mylonitization) locally outcrop on the east coast of PKF, termed the Pinkie Unit. A ~1 km wide shear zone containing ductile to brittle structures and distinct outcrops of greenstones (metagabbros and greenschists), associated with magnetite ore, separates these two contrasting tectonic units. Ten samples of greenstones were collected on the slopes of Lauratzonfjellet and Boureefjellet for petrologic and geochemical analyses. Despite intense localized shearing, the metagabbros are undeformed and preserve coarse crystalline, magmatic texture, which is locally poikilitic. The primary magmatic assemblage consists of brown hornblende, plagioclase, biotite and opaque minerals, with accessory apatite and titanite. No relicts of pyroxenes are preserved. Formation of secondary uralite, sericite and chlorite is observed. Metamorphic assemblage consists of actinolite pseudomorhs after hornblende, epidote, and second generation biotite. Blue amphibole is observed in one sample from Boureefjellet; greenschists from Boureefjellet also contain fibrous blue amphibole, as well as garnets, actinolite, epidote and biotite. Some rocks sampled on Boureefjellet are more strongly deformed and exhibit probably two stages of metamorphism: amphibolite facies metamorphism resulting in blue amphibole-garnet assemblage followed by greenschist facies metamorphism resulting in actinolite-epidote-biotite paragenesis. Parallel and overlapping patterns on chondrite-normalized REE diagrams and spider diagrams indicate that these

  9. Karl Abraham, Sigmund Freud, and the fate of the seduction theory.

    Science.gov (United States)

    Good, M I

    1995-01-01

    Even after Freud had turned his attention away from the seduction theory of neurosogenesis, his close pupil and colleague, Karl Abraham, initially sought to investigate child sexual trauma further. In two of the very first articles on child sexual molestation, Abraham proposed that sexual abuse was particularly common among neurotic and psychotic patients as a result of a "traumatophilic diathesis," a trauma-related conceptual precursor of the repetition compulsion. In their correspondence, Freud trenchantly criticized many aspects of Abraham's papers on the subject of sexual trauma, in contrast to his public endorsement of Abraham's work in this area. For largely transferential reasons that this paper attempts to elucidate, Abraham did not encourage dialogue regarding persistent questions on the seduction issue, ceased publishing on that topic, and for some time controlled his apparently deep rankle over Freud's criticisms and failure to acknowledge Abraham's contribution to the concept of the repetition compulsion. Despite their close friendship and shared intellectual enthusiasm, Freud's response to Abraham's 1907 papers, as well as Abraham's almost uniformly positive disposition toward Freud, apparently prevented Abraham from further developing his observations and ideas on seduction and also lent background to their later clash. Subsequently, there was virtually no further psychoanalytic investigation of the subject of child sexual abuse until the issue arose briefly with Ferenczi in the early 1930s, and only occasionally after that for the next fifty years. The death of Abraham, and then Ferenczi, shortly after disputes with Freud may be among the factors that had an inhibiting effect on an earlier reconsideration of the seduction theory by others. Abraham's previously unheralded concept of traumatophilia has relevance to current clinical controversy regarding constitution and sexual trauma.

  10. Sense and reliability. A conversation with celebrated psychologist Karl E. Weick. Interview by Diane L. Coutu.

    Science.gov (United States)

    Weick, Karl E

    2003-04-01

    Most of us see the organizations we operate in--our schools or companies, for instance--as monolithic and predictable, subjecting us to deadening routines and demanding dehumanizing conformity. But companies are more unpredictable and more alive than we imagine, according to Karl Weick, a psychology professor at the University of Michigan and an expert on organizational behavior. Weick says executives can learn a lot about managing the unexpected from organizations that can't afford surprises in the workplace--nuclear plants, firefighting units, or emergency rooms, for instance. In this conversation with HBR senior editor Diane Coutu, Weick examines the characteristics of these high-reliability organizations (HROs) and suggests ways that other organizations can implement their practices and philosophies. The key difference between high-reliability organizations and other companies is the mindfulness with which people in most HROs react to even very weak signs that some kind of change or danger is approaching. For instance, nuclear-plant workers Weick has studied immediately readjust dials and system commands when an automated system doesn't respond as expected. Weick contrasts this with Ford's inability to pick up on weak signs in the 1970s that there were lethal problems with the design of the Pinto gas tank. HROs are fixated on failure. They eschew plans and blueprints, looking instead for the details that might be missing. And they refuse to simplify reality, Weick says. Indeed, by cultivating broad work experiences and enlarging their repertoires, generalist executives can avoid getting paralyzed by "cosmology episodes"--events that make people feel as though the universe is no longer a rational, orderly system.

  11. El Marx de Dussel: Notas acerca de la recepción dusseliana de la obra teórica de Karl Marx The Marx of Dussel: Notes on dusselian receipt of the theoretical work of Karl Marx

    Directory of Open Access Journals (Sweden)

    Flavio Hernán Teruel

    2010-06-01

    Full Text Available A partir de su exilio en México, a mediados de la década del setenta del siglo pasado, Enrique Dussel se entrega a la tarea de "leer seria y directamente" la obra teórica de Karl Marx producida entre los años 1857 y 1882. Al cabo de diez semestres de arduo trabajo, el resultado es una interpretación novedosa de las cuatro redacciones de El Capital. En efecto, ante los ojos de Dussel la obra maestra de Karl Marx se revela no solo como un tratado de economía sino antes bien como uno de antropología y ética. Marx, afirma Dussel, "deconstruye la economía capitalista críticamente y la reconstruye antropológica y éticamente". Asimismo, Dussel descubre que la producción teórica de Marx quedó inconclusa y, sobre todo, abierta a futuros desarrollos. Para el filósofo mendocino es necesario, en nuestro tiempo, no solo reinterpretar la totalidad de la obra de Marx sino también continuar su labor teórica, en especial desde América Latina, para el estudio del capitalismo periférico latinoamericano. Nuestro interés es indicar aquellos elementos que constituyen lo novedoso en la interpretación dusseliana de la obra teórica de Marx.From his exile in Mexico in the mid seventies of last century, Enrique Dussel is given the task of "reading seriously and directly" the theoretical work of Karl Marx produced between 1857 and 1882. After ten semesters of hard work, the result is a novel interpretation of the four drafts of The Capital. Indeed, in the eyes of Dussel, the masterpiece of Karl Marx is revealed not only as an economic treatise but rather as an anthropology and ethics. Marx "capitalist economy critically deconstructs and reconstructs anthropological and ethically". Moreover, Dussel finds that the theoretical yield of Marx was inconclusive and, above all, open to future developments. For the philosopher is needed in our time, not only reinterpret the whole work of Marx but also to continue his theoretical work, especially from Latin

  12. A combined in situ XAS-XRPD-Raman study of Fischer-Tropsch synthesis over a carbon supported Co catalyst

    DEFF Research Database (Denmark)

    Tsakoumis, Nikolaos E.; Dehghan, Roya; Johnsen, Rune

    2013-01-01

    A cobalt based Fischer-Tropsch synthesis (FTS) catalyst, supported on a carbon nanofibers/carbon felt composite (Co/CNF/CF) was studied in situ at realistic conditions. The catalyst was monitored by Xray absorption spectroscopy (XAS), high-resolution X-ray powder diffraction (HR-XRPD) and Raman s...

  13. Differential Gene Expression in the Nucleus Accumbens and Frontal Cortex of Lewis and Fischer 344 Rats Relevant to Drug Addiction

    Science.gov (United States)

    Higuera-Matas, A; Montoya, G. L; Coria, S.M; Miguéns, M; García-Lecumberri, C; Ambrosio, E

    2011-01-01

    Drug addiction results from the interplay between social and biological factors. Among these, genetic variables play a major role. The use of genetically related inbred rat strains that differ in their preference for drugs of abuse is one approach of great importance to explore genetic determinants. Lewis and Fischer 344 rats have been extensively studied and it has been shown that the Lewis strain is especially vulnerable to the addictive properties of several drugs when compared with the Fischer 344 strain. Here, we have used microarrays to analyze gene expression profiles in the frontal cortex and nucleus accumbens of Lewis and Fischer 344 rats. Our results show that only a very limited group of genes were differentially expressed in Lewis rats when compared with the Fischer 344 strain. The genes that were induced in the Lewis strain were related to oxygen transport, neurotransmitter processing and fatty acid metabolism. On the contrary genes that were repressed in Lewis rats were involved in physiological functions such as drug and proton transport, oligodendrocyte survival and lipid catabolism. These data might be useful for the identification of genes which could be potential markers of the vulnerability to the addictive properties of drugs of abuse. PMID:21886580

  14. The work of Otto Fischer and the historical development of his method of principal vectors for mechanism and machine science

    NARCIS (Netherlands)

    Wijk, van der Volkert; Herder, Just L.; Koetsier, T.; Ceccarelli, M.

    2012-01-01

    This article gives an overview of the distinctive work of Otto Fischer (1861-1916) on the motion of the human musculoskeletal system. In order to be able to derive the individual muscle forces for human in motion, he invented the method of principal vectors to describe the motion of the centers-of-m

  15. Subacute (28-day) toxicity of furfural in Fischer 344 rats: A comparison of the oral and inhalation route

    NARCIS (Netherlands)

    Arts, J.H.E.; Muijser, H.; Appel, M.J.; Kuper, C.F.; Bessems, J.G.M.; Woutersen, R.A.

    2004-01-01

    The subacute oral and inhalation toxicity of furfural vapour was studied in Fischer 344 rats to investigate whether route-to-route extrapolation could be employed to derive the limit value for inhalation exposure from oral toxicity data. Groups of 5 rats per sex were treated by gavage daily for 28 d

  16. Secondary reactions of primary products of the Fischer-Tropsch synthesis: Part 1. The role of ethene

    NARCIS (Netherlands)

    Snel, Ruud; Espinoza, Rafael L.

    1987-01-01

    Co-feeding experiments have shown that ethene readily initiates the Fischer-Tropsch synthesis without altering the chain-growth probability, even when it is present in high concentrations. Propagation by ethene was found to be unlikely. When present in concentrations of 5 mol% or higher, ethene sub

  17. Synthesis of Fischer indole derivatives using carboxyl-functionalized ionic liquid as an efficient and recyclable catalyst

    Institute of Scientific and Technical Information of China (English)

    Feng Ping Yi; Hai Yang Sun; Xian Hua Pan; Yuan Xu; Ji Zong Li

    2009-01-01

    Fischer indole cyclization of phenylhydrazine and various ketones using carboxyl-functionalized ionic liquid, 1-carboxymethyl-3-methylimidazolium tetrafluoroborate (abbreviated as [cmmim][BF4]) as catalyst was successfully performed. The yields of thetarget compounds were 80-92%, the purities were 96-98%. The catalyst could be rocovered and reused for at least six times without significant loss in activity.

  18. Effect of dietary galacto-oligosaccharides on azoxymethane-induced aberrant crypt foci and colorectal cancer in Fischer 344 rats

    NARCIS (Netherlands)

    Wijnands, M.V.W.; Schoterman, H.C.; Bruijntjes, J.P.; Hollanders, V.M.H.; Woutersen, R.A.

    2001-01-01

    The aim of the present study was to investigate the effects of galacto-oligosaccharides (GOS, Elix'or) on the development of aberrant crypt foci (ACF) and colorectal tumours in rats treated with azoxymethane (AOM). Two groups of 102 male Fischer 344 rats were injected twice with AOM to induce colore

  19. Silicon carbide coated with TiO2 with enhanced cobalt active phase dispersion for Fischer-Tropsch synthesis.

    Science.gov (United States)

    Liu, Yuefeng; Florea, Ileana; Ersen, Ovidiu; Pham-Huu, Cuong; Meny, Christian

    2015-01-04

    The introduction of a thin layer of TiO2 on β-SiC allows a significant improvement of the cobalt dispersion. This catalyst exhibits an excellent and stable catalytic activity for the Fischer-Tropsch synthesis (FTS) with high C5+ selectivity, which contributes to the development of a new active catalyst family in the gas-to-liquid process.

  20. In situ x-ray absorption of Co/Mn/TiO2 catalysts for Fischer-Tropsch synthesis

    NARCIS (Netherlands)

    Morales, F; de Groot, FMF|info:eu-repo/dai/nl/08747610X; Glatzel, P; Kleimenov, E; Bluhm, H; Havecker, M; Knop-Gericke, A; Weckhuysen, BM|info:eu-repo/dai/nl/285484397

    2004-01-01

    The reduction behavior of Co/TiO2 and Co/Mn/TiO2 catalysts for Fischer-Tropsch synthesis has been investigated by soft X-ray absorption spectroscopy (XAS). In situ XAS measurements of the L-2,L-3 edges of Co and Mn have been carried out during reduction treatments of the samples in H-2 at a pressure

  1. Different effects of diazepam in Fischer rats and two stocks of Wistar rats in tests of anxiety.

    Science.gov (United States)

    Bert, B; Fink, H; Sohr, R; Rex, A

    2001-01-01

    The behaviour of animals in tests of anxiety varies between strains, even in identical tests and surroundings. To evaluate the results obtained, a more detailed knowledge of the behaviour of different rat strains is indispensable. Identically raised Fischer 344 rats and two stocks of Wistar rats were examined in two animal tests of anxiety: the X-maze and a modified open-field test following diazepam treatment (0.5-4.0 mg/kg). Harlan-Wistar rats were the least 'anxious' when the behaviour of vehicle treated controls was compared. The largest effect of the anxiolytic diazepam, however, was observed in Harlan-Fischer rats. To determine possible reasons for strain and stock differences, plasma concentrations of diazepam and metabolites and concentrations of serotonin (5-HT) in the CNS were measured. Plasma concentrations of diazepam and metabolites differed between the strains with the Harlan-Fischer rats showing higher diazepam concentrations. 5-HT levels in discrete brain regions varied with Harlan-Fischer rats having higher 5-HT concentrations. Strain differences influence the anxiety-associated behaviour of untreated animals and the effect of anxiolytics.

  2. 33 CFR 100.124 - Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York.

    Science.gov (United States)

    2010-07-01

    ... South Bay Cross Bay Swim, Great South Bay, New York. 100.124 Section 100.124 Navigation and Navigable... NAVIGABLE WATERS § 100.124 Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York... swimmer or safety craft on the swim event race course bounded by the following points: Starting Point...

  3. Fischer-tropsch synthesis on iron-based catalysts: the effect of co-feeding small oxygenates

    NARCIS (Netherlands)

    Snel, Ruud; Espinoza, Rafael L.

    1989-01-01

    Co-feeding experiments have shown that ethers can participate substantially in the Fischer-Tropsch synthesis with iron catalysts. Dimethyl ether is thought to be capable of building up surface complexes which are very similar to those naturally occurring during synthesis. Diethyl ether undergoes rap

  4. Differential gene expression in the nucleus accumbens and frontal cortex of lewis and Fischer 344 rats relevant to drug addiction.

    Science.gov (United States)

    Higuera-Matas, A; Montoya, G L; Coria, S M; Miguéns, M; García-Lecumberri, C; Ambrosio, E

    2011-03-01

    Drug addiction results from the interplay between social and biological factors. Among these, genetic variables play a major role. The use of genetically related inbred rat strains that differ in their preference for drugs of abuse is one approach of great importance to explore genetic determinants. Lewis and Fischer 344 rats have been extensively studied and it has been shown that the Lewis strain is especially vulnerable to the addictive properties of several drugs when compared with the Fischer 344 strain. Here, we have used microarrays to analyze gene expression profiles in the frontal cortex and nucleus accumbens of Lewis and Fischer 344 rats. Our results show that only a very limited group of genes were differentially expressed in Lewis rats when compared with the Fischer 344 strain. The genes that were induced in the Lewis strain were related to oxygen transport, neurotransmitter processing and fatty acid metabolism. On the contrary genes that were repressed in Lewis rats were involved in physiological functions such as drug and proton transport, oligodendrocyte survival and lipid catabolism.These data might be useful for the identification of genes which could be potential markers of the vulnerability to the addictive properties of drugs of abuse.

  5. Effects of loading and synthesis method of titania-supported cobalt catalysts for Fischer-Tropsch synthesis

    NARCIS (Netherlands)

    Eschemann, Thomas O.; Bitter, Johannes H.; De Jong, Krijn P.

    2014-01-01

    Because of their high activity and selectivity to C5+ hydrocarbons in the Fischer-Tropsch, process, titania-supported cobalt catalysts have received great interest from industrial and academic, institutions. Here, we report on three catalyst preparation procedures, incipient wetness impregnation (IW

  6. Case 3018. Cervus gouazoubira Fischer, 1814 (currently Mazama gouazoubira; Mammalia, Artiodactyla): proposed conservation as the correct original spelling

    Science.gov (United States)

    Gardner, A.L.

    1999-01-01

    The purpose of this application is to conserve the spelling of the specific name of Cervus gouazoubira Fischer, 1814 for the brown brocket deer of South America (family Cervidae). This spelling, rather than the original gouazoubira, has been in virtually universal usage for almost 50 years.

  7. 'Projecting the future in German art historiography of the nineteenth century: Franz Kugler, Karl Schnaase, and Gottfried Semper'

    Directory of Open Access Journals (Sweden)

    Henrik Karge

    2013-12-01

    Full Text Available In the mid-nineteenth century Franz Kugler and Karl Schnaase decisively shaped the conception of art history as a discipline. Both explored connections between art of former epochs and that of the present. They understood the art of their day to be the result of a tradition of modernity based on the Renaissance and pointing into the future. Schnaase took an evolutionistic view similar to that of the architect Gottfried Semper: both advised against planning a programmatic new style. For Semper, the potential of new developments lay in the continuation of design patterns inherited from the earliest humans.

  8. The democratic origins of the term "group analysis": Karl Mannheim's "third way" for psychoanalysis and social science.

    OpenAIRE

    Winship, G.

    2003-01-01

    It is well known that Foulkes acknowledged Karl Mannheim as the\\ud first to use the term ‘group analysis’. However, Mannheim’s work is\\ud otherwise not well known. This article examines the foundations of\\ud Mannheim’s sociological interest in groups using the Frankfurt\\ud School (1929–1933) as a start point through to the brief correspondence\\ud of 1945 between Mannheim and Foulkes (previously\\ud unpublished). It is argued that there is close conjunction between\\ud Mannheim’s and Foulkes’s r...

  9. O dilema da Social-Democracia (2) - Reforma e Revolução: Bernstein, Rosa Luxemburgo e Karl Kautsky

    OpenAIRE

    Antonio Ozaí da Silva

    2011-01-01

    Análise do “Bernstein-Debatte”, os argumentos revisionistas e a crítica de Rosa Luxemburgo e Karl Kautsky e os rumos da social-democracia alemã entre a prática reformista e a retóric...

  10. [The Karl-Sudhoff-Institute in Leipzig and the academic discipline history of medicine in the GDR].

    Science.gov (United States)

    Kästner, Ingrid

    2014-01-01

    Developmental trends, focus of research and the methods by which work in the field of the History of Medicine was organised in the German Democratic Republic (East Germany) is presented through the example of the Karl Sudhoff Institute in Leipzig, the largest Institute for the study of the History of Medicine in the GDR. The article follows the succession of the Directors, and includes, in addition to descriptions of research and publishing activities, appendices on the work of the Society for the History of Medicine in the German Democratic Republic as well as the historical medical collections.

  11. O dilema da Social-Democracia (2 - Reforma e Revolução: Bernstein, Rosa Luxemburgo e Karl Kautsky

    Directory of Open Access Journals (Sweden)

    Antonio Ozaí da Silva

    2011-03-01

    Full Text Available

    Análise do “Bernstein-Debatte”, os argumentos revisionistas e a crítica de Rosa Luxemburgo e Karl Kautsky e os rumos da social-democracia alemã entre a prática reformista e a retórica revolucionária. 

  12. Conversion enhancement of tubular fixed-bed reactor for Fischer-Tropsch synthesis using static mixer

    Institute of Scientific and Technical Information of China (English)

    Phavanee Narataruksa; Sabaithip Tungkamani; Karn Pana-Suppamassadu; Phongsak Keeratiwintakorn; Siriluck Nivitchanyong; Piyapong Hunpinyo; Hussanai Sukkathanyawat; Prayut Jiamrittiwong; Visarut Nopparat

    2012-01-01

    Recently,Fischer-Tropsch synthesis (FTS) has become an interesting technology because of its potential role in producing biofuels via Biomassto-Liquids (BTL) processes.In Fischer-Tropsch (FT) section,biomass-derived syngas,mainly composed of a mixture of carbon monoxide (CO)and hydrogen (H2),is converted into various forms of hydrocarbon products over a catalyst at specified temperature and pressure.Fixed-bed reactors are typically used for these processes as conventional FT reactors.The fixed-bed or packed-bed type reactor has its drawbacks,which are heat transfer limitation,i.e.a hot spot problem involved highly exothermic characteristics of FT reaction,and mass transfer limitation due to the condensation of liquid hydrocarbon products occurred on catalyst surface.This work is initiated to develop a new chemical reactor design in which a better distribution of gaseous reactants and hydrocarbon products could be achieved,and led to higher throughput and conversion.The main goal of the research is the enhancement of a fixed-bed reactor,focusing on the application of KenicsTM static mixer insertion in the tubular packed-bed reactor.Two FTS experiments were carried out using two reactors i.e.,with and without static mixer insertion within catalytic beds.The modeled syngas used was a mixed gas composed of H2/CO in 2 ∶ 1 molar ratio that was fed at the rate of 30 mL(STP)·min-1 (GHSV ≈ 136 mL·g-1cat·h-1) into the fixed Ru supported aluminum catalyst bed of weight 13.3 g.The reaction was carried out at 180 ℃ and atmospheric pressure continuously for 36 h for both experiments.Both transient and steady-state conversions (in terms of time on stream) were reported.The results revealed that the steady-state CO conversion for the case using the static mixer was approximately 3.5 times higher than that of the case without static mixer.In both cases,the values of chain growth probability of hydrocarbon products (α) for Fischer-Tropsch synthesis were 0.92 and 0.89 for

  13. Titrated flow versus fixed flow Bubble Nasal CPAP for respiratory distress in preterm neonates.

    Directory of Open Access Journals (Sweden)

    Srinivas eMurki

    2015-10-01

    Full Text Available Background: The clinical effects of a pre-fixed flow of air-oxygen versus a flow titrated according to visible bubbling are not well understood.Objective: To compare the effects of a fixed flow (5 L/min and titrated flow ( flow just enough to ensure bubbling at different set pressures on delivered intra-prong pressure, gas exchange and clinical parameters in preterm infants on bubble CPAP for respiratory distress.Methods: Preterm infants less than 35 weeks gestation on bubble CPAP and less than 96 h of age, were enrolled in this cross over study. They were subjected to 30 minute periods of titrated flow and fixed flow. At the end of both epochs, gas flow rate, set pressure, FiO2, SpO2, Silverman retraction score, respiratory rate , abdominal girth, and blood gases were recorded. The delivered intra-prong pressure was measured by an electronic manometer. Results: Sixty nine recordings were made in 54 infants. For each of the set CPAP pressures (4, 5 and 6 cm H2O, the mean delivered pressure with a fixed flow of 5 L/min was higher than that delivered by the titrated flow. During the fixed flow epoch, the delivered pressure was closer to and higher than the set pressure resulting in higher PaO2 and lower PaCO2 as compared to titrated flow epoch. In the titrated flow period, the delivered pressure was consistently lower than the set pressure. Conclusion: In preterm infants on bubble CPAP with set pressures of 4 to 6 cm H2O, a fixed flow of 5 L/min is more effective than a flow titrated to ensure adequate visible bubbling. It achieves higher delivered pressures, better oxygenation and ventilation.

  14. Emissions from Diesel and Gasoline Vehicles Fuelled by Fischer-Tropsch Fuels and Similar Fuels

    DEFF Research Database (Denmark)

    Larsen, Ulrik; Lundorff, Peter; Ivarsson, Anders

    2007-01-01

    vehicles fuelled by Fischer Tropsch (FT) based diesel and gasoline fuel, compared to the emissions from ordinary diesel and gasoline. The comparison for diesel fuels was based on a literature review, whereas the gasoline comparison had to be based on our own experiments, since almost no references were...... and an alkylate fuel (Aspen), which was taken to be the ultimate formula of FT gasoline. FT based diesel generally showed good emission performance, whereas the FT based gasoline not necessary lead to lower emissions. On the other hand, the Aspen fuel did show many advantages for the emissions from the gasoline......The described investigation was carried out under the umbrella of IEA Advanced Motor Fuels Agreement. The purpose was to evaluate the emissions of carbon monoxide (CO), unburned hydrocarbons (HC), nitrogen oxides (NOx), particulate matter (PM) and polycyclic aromatic hydrocarbons (PAH) from...

  15. Study on iron-manganese catalysts for Fischer-Tropsch synthesis

    Institute of Scientific and Technical Information of China (English)

    MOSTAFA FEYZI; FATANEH JAFARI

    2012-01-01

    Iron-manganese catalysts were prepared by co-precipitation method.Characterization of catalysts was carried out by using X-ray diffraction (XRD),scanning electron microscopy (SEM),temperature program reduction (TPR),N2 adsorptiondesorption measurements.The results from catalytic performance tests in Fischer-Tropsch synthesis showed that the iron-manganese catalysts are supersensitive to catalyst composition and materials source.It was found that C2~4 light olefins increased while CH4 and CO2 decreased by using iron-manganese catalyst prepared from iron (Ⅱ) sulfate (A catalyst).The activity and selectivity of A catalyst was studied in different operational conditions.The results showed that the best operational conditions for C2~4 light olefins production were H2/CO=1/1 (GHSV=2 400 h-1) at 260 ℃ under 0.3 MPa total pressure.

  16. Kinetic Rates of the Fischer Tropsch Synthesis on a Co/Nb2O5 Catalyst

    Institute of Scientific and Technical Information of China (English)

    Víctor R.Ahón; Paulo L.C.Lage; Carlos D.D.de Souza; Fabiana M.Mendes; Martin Schmal

    2006-01-01

    The kinetics of the Fischer-Tropsch reaction over a Co/Nb2O5 catalyst in a fixed bed reactor was investigated experimentally. Experiments were carried out under isothermal and isobaric conditions (T=543 K, P=2.1 MPa) and under different conditions of several H2/CO feed molar ratio (0.49-4.79), space velocities (0.2-3.8 h-1), mass of catalyst (0.3-1.5 g), and CO conversion (10%-29%).Synthesis gas conversion was measured and data were reduced to estimate the kinetic parameters for different Langmuir-Hinshelwood rate expressions. Differential and integral reactor models were used for the nonlinear regression of kinetics parameters. One of the rate equations could well explain the data. The hydrocarbon product distributions that were experimentally determined exhibited an unusual behavior,and a possible explanation was discussed.

  17. Morphology Changes of Co Catalyst Nanoparticles at the Onset of Fischer-Tropsch Synthesis

    DEFF Research Database (Denmark)

    Høydalsvik, Kristin; Fløystad, Jostein B.; Voronov, Alexey

    2014-01-01

    Cobalt nanoparticles play an important role as catalysts for the Fischer-Tropsch synthesis, which is an attractive route for production of synthetic fuels. It is of particular interest to understand the varying conversion rate during the first hours after introducing synthesis gas (H-2 and CO...... of the cobalt particles, it is important to develop methods to gain surface-specific structural information under realistic processing conditions. We addressed this challenge using small-angle X-ray scattering (SAXS), a technique exploiting the penetrating nature of X-rays to provide information about particle...... morphology during in situ experiments. Simultaneous wide-angle X-ray scattering was used for monitoring the reduction from oxide to catalytically active metal cobalt, and anomalous SAXS was used for distinguishing the cobalt particles from the other phases present. After introducing the synthesis gas, we...

  18. Bridging complexes of rare earth and cobalt cluster as catalyst precursors for Fischer-Tropsch synthesis

    Institute of Scientific and Technical Information of China (English)

    ZENG Shanghong; DU Dongping; BAI Fenghua; SU Haiquan

    2011-01-01

    Three new bridging complexes of rare earth and cobalt cluster were synthesized and characterized via ICP, IR and TG techniques.The structure of the complexes was speculated as: two rare earth atoms were bridged with four CF3COO-, and rare earth atoms were coordinated with cobalt carbonyl clusters to form a steady structure. Application of the complexes as the catalyst precursors was explored for Fischer-Tropsch synthesis. The study showed that the bridging complexes of rare earth and cobalt cluster had large molecular size and were difficult to enter pore path of γ-Al2O3, so they were dispersed on the surface of γ-A12O3 support. In addition, the performance of Co(Ce)/γ-Al2O3 was the best among the catalysts with complex as precursor and maintained 77.7% CO conversion at 220 ℃ for 80 operation hours.

  19. Modeling of Fischer-Tropsch Synthesis in a Slurry Reactor with Water Permeable Membrane

    Institute of Scientific and Technical Information of China (English)

    Fabiano A. N. Fernandes

    2007-01-01

    Fischer-Tropsch synthesis is an important chemical process for the production of liquid fuels and olefins. In recent years, the abundant availability of natural gas and the increasing demand of olefins, diesel, and waxes have led to a high interest to further develop this process. A mathematical model of a slurry membrane reactor used for syngas polymerization was developed to simulate and compare the maximum yields and operating conditions in the reactor with that in a conventional slurry reactor.The carbon polymerization was studied from a modeling point of view in a slurry reactor with a water permeable membrane and a conventional slurry reactor. Simulation results show that different parameters affect syngas conversion and carbon product distribution, such as the hydrogen to carbon monoxide ratio,and the membrane parameters such as membrane permeance.

  20. Fischer matrices of Dempwolff group $2^{5}{^{cdot}}GL(5,2$

    Directory of Open Access Journals (Sweden)

    Ayoub Basheer Mohammed Basheer

    2012-12-01

    Full Text Available In cite{Demp2} Dempwolff proved the existence of a group of theform $2^{5}{^{cdot}}GL(5,2$ (a non split extension of theelementary abelian group $2^{5}$ by the general linear group$GL(5,2$. This group is the second largest maximal subgroup of thesporadic Thompson simple group $mathrm{Th}.$ In this paper wecalculate the Fischer matrices of Dempwolff group $overline{G} =2^{5}{^{cdot}}GL(5,2.$ The theory of projective characters isinvolved and we have computed the Schur multiplier together with aprojective character table of an inertia factor group. The fullcharacter table of $overline{G}$ is then can be calculated easily.

  1. Particle size effects in Fischer-Tropsch synthesis by Co catalyst supported on carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    Ali Nakhaei Pour; Elham Hosaini; Mohammad Izadyar; Mohammad Reza Housaindokht

    2015-01-01

    The effect of Co particle size on the Fischer-Tropsch synthesis (FTS) activity of carbon nanotube (CNT)-supported Co catalysts was investigated. Microemulsion (using water-to-surfactant molar ratios of 2 to12) and impregnation techniques were used to prepare catalysts with different Co particle sizes. Kinetic studies were performed to understand the effect of Co particle size on catalytic activity. Size-dependent kinetic parameters were developed using a thermodynamic method, to evaluate the structural sensitivity of the CNT-supported Co catalysts. The size-independent FTS reaction rate constant and size-independent adsorption parameter increased with increasing reac-tion temperature. The Polani parameter also depended on catalyst particle size, because of changes in the catalyst surface coverage.

  2. Effect of Several Anions on Fe-Based Catalyst for Fischer-Tropsch Synthesis

    Institute of Scientific and Technical Information of China (English)

    Jingchang Zhang; Xuehua Guo; Weiliang Cao

    2007-01-01

    The influence of several anions on Fe-based Fischer-Tropsch catalyst, used in the synthesis of light olefins from synthesis gas, was studied. The results indicated that the addition of anions resulted in the reduction of catalytic activity. When the anion content in the catalyst was 500 ppm, the influence of different anions on the catalysis activity was as follows: S2->Cl->SO42->NO3-. The addition of S2- improved the selectivity of total hydrocarbons in the products, and Cl- reduced this selectivity but increased the olefin content in the total hydrocarbons at the same time. When the contents of S2- and Cl- in the catalyst were less than 50 ppm, their influence could be ignored. The XRD results indicated that the addition of anions reduced the contents of a-Fe and Fe3C, which were the active components in the catalyst.

  3. Separation of Fischer-Tropsch Wax Products from Ultrafine Iron Catalyst Particles

    Energy Technology Data Exchange (ETDEWEB)

    Amitava Sarkar; James K. Neathery; Burtron H. Davis

    2006-12-31

    A fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of operation since the reaction is highly exothermic. Consequently, heavy wax products in one approach may be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase iron-based FTS and is a key factor for optimizing operating costs. The separation problem is further compounded by attrition of iron catalyst particles and the formation of ultra-fine particles.

  4. Morphological transformation during activation and reaction of an iron Fischer-Tropsch catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, N.B.; Kohler, S.; Harrington, M. [Sandia National Lab., Albuquerque, NM (United States)] [and others

    1995-12-31

    The purpose of this project is to support the development of slurry-phase bubble column processes being studied at the La Porte Alternative Fuel Development Unit. This paper describes the aspects of Sandia`s recent work regarding the advancement and understanding of the iron catalyst used in the slurry phase process. A number of techniques were used to understand the chemical and physical effects of pretreatment and reaction on the attrition and carbon deposition characteristics of iron catalysts. Unless otherwise stated, the data discussed was derived form experiments carried out on the catalyst chosen for the summer 1994 Fischer-Tropsch run at LaPorte, UCI 1185-78-370, (an L 3950 type) that is 88% Fe{sub 2}O{sub 3}, 11% CuO, and 0.052%K{sub 2}O.

  5. Preparation of Fischer-Tropsch catalysts from cobalt/iron hydrotalcites

    Energy Technology Data Exchange (ETDEWEB)

    Howard, B.H.; Boff, J.J.; Zarochak, M.F. [Pittsburgh Energy Technology Center, PA (United States)] [and others

    1995-12-31

    Compounds with the (hydrotalcites) have properties that make them attractive as precursors for Fischer-Tropsch catalysts. A series of single-phase hydrotalcites with cobalt/iron atom ratios ranging from 75/25 to 25/75 has been synthesized. Mixed cobalt/iron oxides have been prepared from these hydrotalcites by controlled thermal decomposition. Thermal decomposition at temperatures below 600 {degrees}C typically produced a single-phase mixed metal oxide with a spinel structure. The BET surface areas of the spinal samples have been found to be as high as about 150 m{sup 2}/g. Appropriate reducing pretreatments have been developed for several of these spinels and their activity, selectivity, and activity and selectivity maintenance have been examined at 13 MPa in a fixed-bed microreactor.

  6. Nucleophilic addition/double cyclization cascade processes between enynyl Fischer carbene complexes and alkynyl malonates.

    Science.gov (United States)

    Álvarez-Fernández, Ana; Suárez-Rodríguez, Tatiana; Suárez-Sobrino, Ángel L

    2014-07-18

    Two new selective cascade processes for enynyl Fischer carbene complexes 1 are described in their reaction with alkynyl malonates. When carbene complexes 1 react with the sodium enolate of homopropargyl malonates 3 a consecutive Michael-type addition/cyclopentannulation/6-exo cyclization takes place leading, in a regio- and stereoselective way, to n/5/6 angular tricyclic compounds 5. Furthermore, when propargylic malonates are used, a delayed protonation of the reaction mixture allows intermediate 1,4-addition adduct Ia to evolve through a 5-exo cyclization, consisting of an intramolecular nucleophilic attack from the central carbon of the allenylmetallate over the triple C-C bond. Further spontaneous cyclopentannulation of the resulting metallatriene gives rise to bicyclic and linear polycyclic compounds 6 and 7, some of them bearing a polyquinane framework.

  7. Co-CeO2/SiO2 Fischer-Tropsch Synthesis Catalyst

    Institute of Scientific and Technical Information of China (English)

    ShiHaibo; LiQiang; DaiXiaoping; YuChangchun; ShenShikong

    2005-01-01

    A series of Co (10.7 wt. %)-CeO2/SiO2 catalysts with various cerium contents was prepared and evaluated. The optimized ceria-promoted catalyst exhibits good activity, high selectivity towards long chain hydrocarbons, and excellent stability. The promotion mechanism of ceria was investigated using X-ray diffraction (XRD), temperature programmed reduction (TPR), H2 temperature programmed surface reaction (H2-TPSR) and transient response technique. It is suggested that the improved catalytic performance of the catalyst modified by ceria be attributed to (1) the improvement in the dispersion of metallic cobalt and the amount of active sites for Fischer-Tropsch Synthesis (FTS), leading to an increased concentration of surface active carbon species and high selectivity towards long chain hydrocarbons; (2) the inhibition of disproportionation of CO and the removal of inactive surface carbon species.

  8. The effect of aging on acetaminophen pharmacokinetics, toxicity and Nrf2 in Fischer 344 rats.

    Science.gov (United States)

    Mach, John; Huizer-Pajkos, Aniko; Cogger, Victoria C; McKenzie, Catriona; Le Couteur, David G; Jones, Brett E; de Cabo, Rafael; Hilmer, Sarah N

    2014-04-01

    We investigated the effect of aging on hepatic pharmacokinetics and the degree of hepatotoxicity following a toxic dose of acetaminophen. Young and old male Fischer 344 rats were treated with 800 mg/kg acetaminophen (young n = 8, old n = 5) or saline (young n = 9, old n = 9). Serum measurements showed old rats treated with acetaminophen had significantly lower serum alanine aminotransferase and higher acetaminophen and acetaminophen glucuronide levels and creatinine, compared with acetaminophen treated young rats (p acetaminophen had lower survival than those from old rats (52.4% ± 5.8%, young; 83.6% ± 1.7%, old, p acetaminophen-induced hepatotoxicity but may increase risk of nephrotoxicity in old age.

  9. Effect of incorporation manner of Zr promoter on precipitated ironbased catalysts for Fischer-Tropsch synthesis

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hao-jian; MA Hong-fang; ZHANG Hai-tao; YING Wei-yong; FANG Ding-ye

    2012-01-01

    The promotional effects of Zr on the structure,reduction,carburization and catalytic behavior of precipitated iron-based Fischer-Tropsch synthesis (FTS) catalysts were investigated.The catalysts were characterized by N2 physisorption,temperature-programmed reduction (TPR),and M(o)ssbauer effect spectroscopy (MES) techniques.As revealed by N2 physisorption,Zr decreased the BET surface area and pore volume of the catalyst.The results of TPR and MES show that Zr suppresses the reduction and carburization of Fe catalysts because of the interaction between Fe and Zr.The FTS reaction results indicate that Zr decreases the FTS activity of Fe catalysts but improves the catalysts' stability.In addition,Zr promoter restraines the formation of light hydrocarbons (methane and C2~C4) and shifts the production distribution to the heavy hydrocarbons.

  10. Optimisation of the Fischer-Tropsch process using zeolites for tail gas separation.

    Science.gov (United States)

    Perez-Carbajo, J; Gómez-Álvarez, P; Bueno-Perez, R; Merkling, P J; Calero, S

    2014-03-28

    This work is aimed at optimizing a Fischer-Tropsch Gas To Liquid (GTL) process by recycling compounds of the expelled gas mixture using zeolites for the separation. To that end, we have performed a computational study on four structures widely used in industry. A range of Si/Al ratios have been explored and the effects of their distribution assessed. The ability of the considered force fields and molecular models to reproduce experimental results has been widely proved in previously reported studies. Since this tail gas is formed by a five-component mixture, namely carbon dioxide, methane, carbon monoxide, nitrogen and hydrogen, molecular simulations present clear advantages over experiments. In addition, the viability of the Ideal Adsorption Solution Theory (IAST) has been evaluated to easily handle further separation steps. On the basis of the obtained results, we provide a separation scheme to perform sequentially the separation of CO2, CH4, CO, N2 and H2.

  11. Origins of Regioselectivity in the Fischer Indole Synthesis of a Selective Androgen Receptor Modulator.

    Science.gov (United States)

    Noey, Elizabeth L; Yang, Zhongyue; Li, Yanwei; Yu, Hannah; Richey, Rachel N; Merritt, Jeremy M; Kjell, Douglas P; Houk, K N

    2017-06-02

    The selective androgen receptor modulator, (S)-(7-cyano-4-(pyridin-2-ylmethyl)-1,2,3,4-tetrahydrocyclopenta[b]indol-2-yl)carbamic acid isopropyl ester, LY2452473, is a promising treatment of side effects of prostate cancer therapies. An acid-catalyzed Fischer indolization is a central step in its synthesis. The reaction leads to only one of the two possible indole regioisomers, along with minor decomposition products. Computations show that the formation of the observed indole is most favored energetically, while the potential pathway to the minor isomer leads instead to decomposition products. The disfavored [3,3]-sigmatropic rearrangement, which would produce the unobserved indole product, is destabilized by the electron-withdrawing phthalimide substituent. The most favored [3,3]-sigmatropic rearrangement transition state is bimodal, leading to two reaction intermediates from one transition state, which is confirmed by molecular dynamics simulations. Both intermediates can lead to the observed indole product, albeit through different mechanisms.

  12. Development of niobium-promoted cobalt catalysts on carbon nanotubes for Fischer-Tropsch synthesis

    Institute of Scientific and Technical Information of China (English)

    Sardar Ali; Noor Asmawati Mohd Zabidi; Duvvuri Subbarao

    2011-01-01

    Cobalt-based catalysts were prepared by a wet impregnation method on carbon nanotubes (CNTs) support and promoted with niobium.Samples were characterized by nitrogen adsorption,TEM,XRD,TPR,TPO and H2-TPD.Addition of niobium increased the dispersion of cobalt but decreased the catalysts reducibility.Fischer-Tropsch synthesis (FTS) was carried out in a fixed-bed microreactor at 543 K,1 atm and H2/CO =2 for 5 h.Addition of niobium enhanced the C5+ hydrocarbons selectivity by 39% and reduced methane selectivity by 59%.These effects were more pronounced for 0.04%Nb/Co/CNTs catalyst,compared with those observed for other niobium compositions.

  13. Trapping Planetary Noble Gases During the Fischer-Tropsch-Type Synthesis of Organic Materials

    Science.gov (United States)

    Nuth, Joseph A.; Johnson, N. M.; Meshik, A.

    2010-01-01

    When hydrogen, nitrogen and CO arc exposed to amorphous iron silicate surfaces at temperatures between 500 - 900K, a carbonaceous coating forms via Fischer-Tropsch type reactions!, Under normal circumstances such a catalytic coating would impede or stop further reaction. However, we find that this coating is a better catalyst than the amorphous iron silicates that initiate these rcactions:u . The formation of a self-perpetuating catalytic coating on grain surfaces could explain the rich deposits of macromolecular carbon found in primitive meteorites and would imply that protostellar nebulae should be rich in organic materiaL Many more experiments are needed to understand this chemical system and its application to protostellar nebulae.

  14. Fischer-Tropsch synthesis on hierarchically structured cobalt nanoparticle/carbon nanofiber/carbon felt composites.

    Science.gov (United States)

    Zarubova, Sarka; Rane, Shreyas; Yang, Jia; Yu, Yingda; Zhu, Ye; Chen, De; Holmen, Anders

    2011-07-18

    The hierarchically structured carbon nanofibers (CNFs)/carbon felt composites, in which CNFs were directly grown on the surface of microfibers in carbon felt, forming a CNF layer on a micrometer range that completely covers the microfiber surfaces, were tested as a novel support material for cobalt nanoparticles in the highly exothermic Fischer-Tropsch (F-T) synthesis. A compact, fixed-bed reactor, made of disks of such composite materials, offered the advantages of improved heat and mass transfer, relatively low pressure drop, and safe handling of immobilized CNFs. An efficient 3-D thermal conductive network in the composite provided a relatively uniform temperature profile, whereas the open structure of the CNF layer afforded an almost 100 % effectiveness of Co nanoparticles in the F-T synthesis in the fixed bed. The greatly improved mass and heat transport makes the compact reactor attractive for applications in the conversion of biomass, coal, and natural gas to liquids.

  15. Intrinsic kinetics of eggshell cobalt catalysts for the Fischer-Tropsch synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Peluso, E.; Galarraga, C. E. [INTEVEP, S. A. Catalisis Aplicada, Caracas (Venezuela); De Lasa, H. I. [University of Western Ontario, Faculty of Engineering Science, London, ON (Canada)

    1998-05-01

    Production of synthetic hydrocarbons via the hydrogenation of carbon monoxide (Fischer-Tropsch synthesis, FT) as a means of producing clean fuels, and thus lessen the environmental burden, was discussed. To reduce transport limitations on the diffusion process through the catalytic pores, the use of pellicular or `eggshell` catalysts, especially eggshell Co-based catalysts, is recommended. These catalysts decrease the transport restrictions and therefore increase the FT reaction rates and C{sub 5}+ selectivity. The present study focuses on the kinetics of the FT reaction in an internally recycled Berty reactor over a Co-Zr/SiO{sub 2} eggshell catalyst by obtaining steady state reactivities at various H{sub 2}/CO ratios, temperatures and pressure ranges. Using statistical methods, the suitability of several kinetics models and possible reaction mechanisms in eggshell catalysts are analyzed. 3 refs.

  16. Immobilised carbon nanotubes as carrier for Co-Fischer-Tropsch synthesis catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Thiessen, J.; Rose, A.; Kiendl, I.; Jess, A. [Bayreuth Univ. (Germany). Dept. of Chemical Engineering; Curulla-Ferre, D. [Total S.A., Gas and Power, Paris La Defense (France)

    2011-07-01

    A possibility to immobilise carbon nanotubes (CNT) to make them applicable in a technical scale fixed bed reactor is studied. The approach to fabricate millimetre scale composites containing CNT presented in this work is to confine the nano-carbon in macro porous ceramic particles. Thus CNT were grown on the inner surface of silica and alumina pellets and spheres, respectively. Cobalt nano particles were successfully deposited on the carbon surface inside the two types of ceramic carriers and the systems were tested in Fischer - Tropsch synthesis (FTS). The cobalt mass related activity of these novel catalysts is similar to a conventional system. The selectivities of the Co/CNT/ceramic composites were compared with non supported CNT and carbon nanofibres (CNF). (orig.)

  17. The role of zeolites in the deactivation of multifunctional Fischer-Tropsch Synthesis catalysts: the interaction between HZSM-5 and Fe-based FT-catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Zonetti, P.C.; Gaspar, A.B.; Mendes, F.M.T.; Appel, L.G., E-mail: lucia.appel@int.gov.br [Instituto Nacional de Tecnologia (INT/MCT), Rio de Janeiro, RJ (Brazil); Avillez, R. R. de [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil); Sousa-Aguiar, E.F. [Centro de Pesquisa Leopoldo Americo Miguez de Mello (CENPES/PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2013-10-15

    In order to produce gasoline directly from syngas, HZSM-5 can be added to the Fischer-Tropsch catalyst. However, this catalytic system shows an important deactivation rate. Aiming at describing this phenomenon, Fe-based catalysts and physical mixtures containing these catalysts and HZSM-5 were employed in this reaction. All these systems were characterized using the following techniques: XRD, XPS, TPR and TPD of CO. This work shows that HZSM-5 interacts with the Fe-based Fischer-Tropsch catalyst during the reduction step, decreasing the Fe concentration on the catalytic surface and thus lowering the activity of the catalytic system in the Fischer-Tropsch Synthesis. (author)

  18. The role of zeolites in the deactivation of multifunctional fischer-tropsch synthesis catalysts: the interaction between HZSM-5 and Fe-based Ft-catalysts

    Directory of Open Access Journals (Sweden)

    P. C. Zonetti

    2013-12-01

    Full Text Available In order to produce gasoline directly from syngas, HZSM-5 can be added to the Fischer-Tropsch catalyst. However, this catalytic system shows an important deactivation rate. Aiming at describing this phenomenon, Fe-based catalysts and physical mixtures containing these catalysts and HZSM-5 were employed in this reaction. All these systems were characterized using the following techniques: XRD, XPS, TPR and TPD of CO. This work shows that HZSM-5 interacts with the Fe-based Fischer-Tropsch catalyst during the reduction step, decreasing the Fe concentration on the catalytic surface and thus lowering the activity of the catalytic system in the Fischer-Tropsch Synthesis.

  19. Computational Fluid Dynamics Study of Channel Geometric Effect for Fischer-Tropsch Microchannel Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Na, Jonggeol; Jung, Ikhwan; Kshetrimayum, Krishnadash S.; Park, Seongho; Park, Chansaem; Han, Chonghun [Seoul National University, Seoul (Korea, Republic of)

    2014-12-15

    Driven by both environmental and economic reasons, the development of small to medium scale GTL(gas-to-liquid) process for offshore applications and for utilizing other stranded or associated gas has recently been studied increasingly. Microchannel GTL reactors have been preferred over the conventional GTL reactors for such applications, due to its compactness, and additional advantages of small heat and mass transfer distance desired for high heat transfer performance and reactor conversion. In this work, multi-microchannel reactor was simulated by using commercial CFD code, ANSYS FLUENT, to study the geometric effect of the microchannels on the heat transfer phenomena. A heat generation curve was first calculated by modeling a Fischer-Tropsch reaction in a single-microchannel reactor model using Matlab-ASPEN integration platform. The calculated heat generation curve was implemented to the CFD model. Four design variables based on the microchannel geometry namely coolant channel width, coolant channel height, coolant channel to process channel distance, and coolant channel to coolant channel distance, were selected for calculating three dependent variables namely, heat flux, maximum temperature of coolant channel, and maximum temperature of process channel. The simulation results were visualized to understand the effects of the design variables on the dependent variables. Heat flux and maximum temperature of cooling channel and process channel were found to be increasing when coolant channel width and height were decreased. Coolant channel to process channel distance was found to have no effect on the heat transfer phenomena. Finally, total heat flux was found to be increasing and maximum coolant channel temperature to be decreasing when coolant channel to coolant channel distance was decreased. Using the qualitative trend revealed from the present study, an appropriate process channel and coolant channel geometry along with the distance between the adjacent

  20. Fischer-Tropsch-synthesis fuels as diesel engine fuel - Fuel of the future

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Erik [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Thermo and Fluid Dynamics

    2000-04-01

    The Fischer-Tropsch (F-T) catalytic conversion process can be used to synthesize diesel fuels from a variety of feedstocks, including coal, natural gas and biomass. Synthetic diesel fuels can have very low sulfur and aromatic content, and excellent auto ignition characteristics. Moreover, Fischer-Tropsch diesel fuels may also be economically competitive with regular diesel fuel if produced in large volumes. The aim of this investigation is to reveal and analyze the effects of F-T fuels on a research diesel engine performance. Previous engine laboratory tests indicate that F-T fuels are promising alternative fuels because they can be used in unmodified diesel engines, and substantial quantitative exhaust emission reductions can be reached. Also substantial qualitative reductions, e.g. reduction of the number of hazardous chemicals and reduction of the concentration of hazardous chemicals in the exhausts may be realised. Since the engine performance is closely related to in-cylinder processes, a detailed thermodynamic analysis has been performed revealing the real thermochemistry history. The experimental results have shown that F-T fuels have a beneficial effect not only on the emission levels, but also on other energetic parameters of the engine. Heat release analysis have shown that ignition delay, cylinder peak pressure, heat release gradient and indicated efficiency are affected as well. Two different mixtures of FT-fuels with variation in carbon chain branching and, to a certain extent, variation in chain length were tested and their results were compared with those obtained from conventional fuel (MK1). The selected optimized F-T fuels mixture were further tested according to the 13 mode ECE R49 test cycle and were found as good competitive alternative diesel fuels.