Sample records for solid-liquid extraction analysis

  1. Analysis of solid-liquid phase change heat transfer enhancement

    张寅平; 王馨


    Solid-liquid phase change processes have two important features: the process is an approximately isothermal process and the heat of fusion of phase change material tends to be much greater than its specific heat. Therefore, if any phase change material adjacent to a hot or cold surface undergoes phase change, the heat transfer rate on the surface will be noticeably enhanced. This paper presents a novel insight into the mechanisms of heat transfer enhancement induced by solid-liquid phase change based on the analogy analysis for heat conduction with an internal heat source and solid-liquid phase change heat transfer. Three degrees of surface heat transfer enhancement for different conditions are explored, and corresponding formulae are written to describe them. The factors influencing the degrees of heat transfer enhancement are clarified and their effects quantitatively analyzed. Both the novel insight and the analysis contribute to effective application of phase change heat transfer enhancement technique.

  2. Solid-liquid solvent extraction of metal ions

    Bo Peng; Haiyan Fan; Jinzhang Gao


    An overview of extraction of some trace metal ions using molten solvent (low melting substance) during last two decadesis presented. The development of this technique since its inception is briefly traced. The comparison of extraction efficiency, thermo-dynamics and kinetics mainly involving extraction of rare earth ions between molten solvent extraction at high temperature and usualliquid-liquid extraction at room temperature are discussed in detail. The various parameters obtained from the previous and presentstudies such as equilibrium extraction constant Kex, pH1/2, thermodynamic and kinetic data are displayed in tabular form. Finally, thecurrent demands, disadvantages and future prospects are also evaluated.

  3. Focused ultrasound solid-liquid extraction for the determination of organic biomarkers in beachrocks.

    Blanco-Zubiaguirre, L; Arrieta, N; Iturregui, A; Martinez-Arkarazo, I; Olivares, M; Castro, K; Olazabal, M A; Madariaga, J M


    Beachrocks are consolidated coastal sedimentary formations resulting mainly from the relative rapid cementation of beach sediments by different calcium carbonate polymorphs. Although previous works have already studied the elemental composition and the mineral phases composing these cements, few of them have focused their attention on the organic matter present therein. This work describes an extraction methodology based on focused ultrasound solid-liquid extraction (FUSLE), followed by analysis using large volume injection (LVI) in a programmable temperature vaporizer (PTV) combined with gas chromatography-mass spectrometry (GC-MS) in order to determine organics such as polycyclic aromatic hydrocarbons (PAHs) and biomarkers (hopanes), which can increase and confirm the information obtained so far. This goal has been achieved after the optimization of the main parameters affecting the extraction procedure, such as, extraction solvent, FUSLE variables (amplitude, extraction time and pulse time) and also variables affecting the LVI-PTV (vent time, injection speed and cryo-focusing temperature). The developed method rendered results comparable to traditional extraction methods in terms of accuracy (77-109%) and repeatability (RSD<23%). Finally, the analyses performed over real beachrock samples from the Bay of Biscay (Northern Spain) revealed the presence of the 16 EPA priority PAHs, as well as some organic biomarkers which could increase the knowledge about such beachrock formation.

  4. Laboratory Production of Lemon Liqueur (Limoncello) by Conventional Maceration and a Two-Syringe System to Illustrate Rapid Solid-Liquid Dynamic Extraction

    Naviglio, Daniele; Montesano, Domenico; Gallo, Monica


    Two experimental techniques of solid-liquid extraction are compared relating to the lab-scale production of lemon liqueur, most commonly named "limoncello"; the first is the official method of maceration for the solid-liquid extraction of analytes and is widely used to extract active ingredients from a great variety of natural products;…

  5. Ionic-liquid-impregnated resin for the microwave-assisted solid-liquid extraction of triazine herbicides in honey.

    Wu, Lijie; Song, Ying; Hu, Mingzhu; Yu, Cui; Zhang, Hanqi; Yu, Aimin; Ma, Qiang; Wang, Ziming


    Microwave-assisted ionic-liquid-impregnated resin solid-liquid extraction was developed for the extraction of triazine herbicides, including cyanazine, metribuzin, desmetryn, secbumeton, terbumeton, terbuthylazine, dimethametryn, and dipropetryn in honey samples. The ionic-liquid-impregnated resin was prepared by immobilizing 1-hexyl-3-methylimidazolium hexafluorophosphate in the microspores of resin. The resin was used as the extraction adsorbent. The extraction and enrichment of analytes were performed in a single step. The extraction time can be shortened greatly with the help of microwave. The effects of experimental parameters including type of resin, type of ionic liquid, mass ratio of resin to ionic liquid, extraction time, amount of the impregnated resin, extraction temperature, salt concentration, and desorption conditions on the extraction efficiency, were investigated. A Box-Behnken design was applied to the selection of the experimental parameters. The recoveries were in the range of 80.1 to 103.4% and the relative standard deviations were lower than 6.8%. The present method was applied to the analysis of honey samples.

  6. Multi-residue analysis of 36 priority and emerging pollutants in marine echinoderms (Holothuria tubulosa) and marine sediments by solid-liquid extraction followed by dispersive solid phase extraction and liquid chromatography-tandem mass spectrometry analysis.

    Martín, J; Zafra-Gómez, A; Hidalgo, F; Ibáñez-Yuste, A J; Alonso, E; Vilchez, J L


    Marine echinoderms are filter-feeding invertebrates widely distributed along the coasts, and which are therefore extensively exposed to anthropogenic xenobiotics. They can serve as good sentinels for monitoring a large variety of contaminants in marine ecosystems. In this context, a multi-residue analytical method has been validated and applied to Holothuria tubulosa specimens and marine sediments for the determination of 36 organic compounds, which belong to some of the most problematic groups of emerging and priority pollutants (perfluoroalkyl compounds, estrogens, parabens, benzophenones, plasticizers, surfactants, brominated flame retardants and alkylphenols). Lyophilization of samples prior to solvent extraction and clean-up of extracts with C18, followed by liquid chromatography-tandem mass spectrometry analysis, is proposed. A Box-Behnken design was used for optimization of the most influential variables affecting the extraction and clean-up steps. For validation, matrix-matched calibration and recovery assay were applied. Linearity (% r(2)) higher than 99%, recoveries between 80% and 114% (except in LAS and NP1EO), RSD (precision) lower than 15% and limits of quantification between 0.03 and 12.5ngg(-1) dry weight (d.w.) were achieved. The method was applied to nine samples of Holothuria collected along the coast of Granada (Spain), and to marine sediments around the animals. The results demonstrated high bioaccumulation of certain pollutants. A total of 25 out of the 36 studied compounds were quantified, being surfactants, alkylphenols, perfluoroalkyl compounds, triclocarban and parabens the most frequently detected. Nonylphenol was found in the highest concentration (340 and 323ngg(-1) d.w. in sediment and Holothuria samples, respectively).

  7. Enhanced mass transfer during solid-liquid extraction of gamma-irradiated red beetroot

    Nayak, Chetan A. [Department of Food Engineering, Central Food Technological Research Institute, Mysore 570 020 (India); Chethana, S. [Department of Food Engineering, Central Food Technological Research Institute, Mysore 570 020 (India); Rastogi, N.K. [Department of Food Engineering, Central Food Technological Research Institute, Mysore 570 020 (India)]. E-mail:; Raghavarao, K.S.M.S. [Department of Food Engineering, Central Food Technological Research Institute, Mysore 570 020 (India)


    The exposure to gamma-irradiation pretreatment increases cell wall permeabilization, resulting in loss of turgor pressure, which led to the increase of extractability of betanin from red beetroot. The degree of extraction of betanin was investigated using gamma irradiation as a pretreatment prior to the solid-liquid extraction process and compared with control beetroot samples. The beetroot subjected to different doses of gamma irradiation (2.5, 5.0, 7.5, 10.0 kGy) and control was dipped in an acetic acid medium (1% v/v) to extract the betanin. The diffusion coefficients for betanin as well as ionic component were estimated considering Fickian diffusion. The results indicated an increase in the diffusion coefficient of betanin (0.302x10{sup -9}-0.463x10{sup -9} m{sup 2}/s) and ionic component (0.248x10{sup -9}-0.453x10{sup -9} m{sup 2}/s) as the dose rate increased (from 2.5 to 10.0 kGy). The degradation constant was found to increase (0.050-0.079 min{sup -1}) with an increase gamma-irradiation doses (2.5-10.0 kGy), indicating lower stability of the betanin as compared to control sample at 65 deg. C.

  8. Development of an Analytical Method Based on Temperature Controlled Solid-Liquid Extraction Using an Ionic Liquid as Solid Solvent

    Zhongwei Pan


    Full Text Available At the present paper, an analytical method based on temperature controlled solid-liquid extraction (TC-SLE utilizing a synthesized ionic liquid, (N-butylpyridinium hexafluorophosphate, [BPy]PF6, as solid solvent and phenanthroline (PT as an extractant was developed to determine micro levels of Fe2+ in tea by PT spectrophotometry. TC-SLE was carried out in two continuous steps: Fe2+ can be completely extracted by PT-[BPy]PF6 or back-extracted at 80 °C and the two phases were separated automatically by cooling to room temperature. Fe2+, after back-extraction, needs 2 mol/L HNO3 as stripping agent and the whole process was determined by PT spectrophotometry at room temperature. The extracted species was neutral Fe(PTmCl2 (m = 1 according to slope analysis in the Fe2+-[BPy]PF6-PT TC-SLE system. The calibration curve was Y = 0.20856X − 0.000775 (correlation coefficient = 0.99991. The linear calibration range was 0.10–4.50 μg/mL and the limit of detection for Fe2+ is 7.0 × 10−2 μg/mL. In this method, the contents of Fe2+ in Tieguanyin tea were determined with RSDs (n = 5 3.05% and recoveries in range of 90.6%–108.6%.

  9. Solid-liquid Extraction Spectrophotometric Determination of Copper with 2,9-dimethyl-1, 10-phenanthroline


    Solid liquid extraction of copper ion (I) with 2, 9-dimethyl-1, 10-phenanthroline (neo-cuproine, DMP) into molten naphthalene followed by chloroform spectrophotometric determination has been studied experimentally. The ternary complex Cu(I)-DMP-ClO4 was extracted quantitatively into molten naphthalene in the range of pH from 5 to 6 at 85℃. Absorbance was spectrophotometrically determined at 459 nm against the reagent blank after the solid naphthalene layer was anhydrously dissolved in chloroform. Beer's law is obeyed over a concentration range of 0.5-70 mg/mL. The molar absorptivity and Sandell's sensitivity are 1.0′104 L/(mol·cm) and 0.0099 mg·cm2 respectively. In addition, the various conditions on determination and the interference of coexisted ions were discussed, and the method was applied to the determination of copper ion both in tea samples and cadmium sulfate reagents. The results are in good agreement with those obtained by ICP AES method.

  10. Spectrofluorimetric determination of melatonin in kernels of four different Pistacia varieties after ultrasound-assisted solid-liquid extraction

    Oladi, Elham; Mohamadi, Maryam; Shamspur, Tayebeh; Mostafavi, Ali


    Melatonin is normally consumed to regulate the body's biological cycle. However it also has therapeutic properties, such as anti-tumor, anti-aging and protects the immune system. There are some reports on the presence of melatonin in edible kernels such as walnuts, but the extraction of melatonin from pistachio kernels is reported here for the first time. For this, the methanolic extract of pistachio kernels was exposed to gas chromatography/mass spectrometry analysis which confirmed the presence of melatonin. A fluorescence-based method was applied for the determination of melatonin in different extracts. When excited at λ = 275 nm, the fluorescence emission intensity of melatonin was measured at λ = 366 nm. Ultrasound-assisted solid-liquid extraction was used for the extraction of melatonin from pistachio kernels prior to fluorimetric determination. To achieve the highest extraction recovery, the main parameters affecting the extraction efficiency such as extracting solvent type and volume, temperature, sonication time and pH were evaluated. Under the optimized conditions, a linear dependence of fluorescence intensity on melatonin concentration was observed in the range of 0.0040-0.160 μg mL-1, with a detection limit of 0.0036 μg mL-1. This method was applied successfully for measuring and comparing the melatonin content in the kernels of four different varieties of Pistacia including Ahmad Aghaei, Akbari, Kalle Qouchi and Fandoghi. In addition, the results obtained were compared with those obtained using GC/MS. A good agreement was observed indicating the reliability of the proposed method.

  11. Development and validation of ultrasound-assisted solid-liquid extraction of phenolic compounds from waste spent coffee grounds.

    Al-Dhabi, Naif Abdullah; Ponmurugan, Karuppiah; Maran Jeganathan, Prakash


    In this current work, Box-Behnken statistical experimental design (BBD) was adopted to evaluate and optimize USLE (ultrasound-assisted solid-liquid extraction) of phytochemicals from spent coffee grounds. Factors employed in this study are ultrasonic power, temperature, time and solid-liquid (SL) ratio. Individual and interactive effect of independent variables over the extraction yield was depicted through mathematical models, which are generated from the experimental data. Determined optimum process conditions are 244W of ultrasonic power, 40°C of temperature, 34min of time and 1:17g/ml of SL ratio. The predicted values were in correlation with experimental values with 95% confidence level, under the determined optimal conditions. This indicates the significance of selected method for USLE of phytochemicals from SCG. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Antioxidant and antibacterial activity of solid-liquid and enzyme-assisted extraction of phenolic compound from three species of tropical Sargassum

    Puspita, M.; Deniel, M.; Widowati, I.; Radjasa, O. K.; Douzenel, P.; Bedoux, G.; Bourgougnon, N.


    Sargassum has been well acknowledged for the potential natural product of its phlorotannins. Solid-liquid extraction (SLE) is the most common method used to extract them. However, this method has some drawbacks such as low yield and toxic. An alternative ecofriendly method has been proposed, i.e. enzyme-assisted extraction (EAE), proven to be more efficient. The aim is to compare the efficiency of SLE and EAE concerning their extraction yield, total phenolic content and antioxidant activity. S. aquifolium, S. ilicifolium and S. polycystum were extracted using water, methanol, methanol 50%, and ethanol 75% and enzymes (Viscozyme and Protamex). Total phenolic content (TPC) was analyzed by Folin-Ciocalteu and antioxidant activity via DPPH and FRAP analysis. This study implied that bioactivity of Sargassum extracted with enzymes is better compared to the one using organic solvents.

  13. Solid-Liquid Extraction of Some Lanthanide Complexes with 1-Nitroso-2-Naphthol


    The extraction behavior of Sm(III), Eu(III) ,Er(III) and Yb(III) with 1- nitroso -2- naphthol (HA) in paraffin has been studied. The composition of extracted complexes has been determined to be LnA3 by slope analysis method. The effect of temperature on extraction system is also investigated and thermodynamic parameters are obtained.

  14. Analysis of stability of a planar solid-liquid interface in a dilute binary alloy

    Laxmanan, V.


    This paper reconsiders the question of stability of a planar solid-liquid interface in an undercooled alloy melt without making the restrictive assumption of no heat flow in the solid (i.e., Gs = 0). The results of this analysis indicate that, provided the thermal gradient on the solid side of the interface, Gs, is positive, stability can be achieved in an undercooled alloy melt for growth rates R greater than Ra (where Ra is the absolute stability limit of Mullins and Sekerka, 1964). Thus, the absolute stability criterion for steady-state planar growth in an undercooled alloy melt is the same as derived earlier by Mullins and Sekerka for directional solidification. Relaxing the restrictive assumption of Gs = 0 also reveals that there is a regime of stability for low growth rates and low supercoolings.

  15. Simultaneous monitoring of protein adsorption at the solid-liquid interface from sessile solution droplets by ellipsometry and axisymmetric drop shape analysis by profile

    Wormeester, H; Busscher, HK


    In this paper two in situ techniques are combined to simultaneously examine protein adsorption at the solid-liquid interface from sessile solution droplets. With axisymmetric drop shape analysis by profile (ADSA-P) the change in solid-liquid interfacial tension is determined, while ellipsometry is e

  16. "Bligh and Dyer" and Folch Methods for Solid-Liquid-Liquid Extraction of Lipids from Microorganisms. Comprehension of Solvatation Mechanisms and towards Substitution with Alternative Solvents.

    Breil, Cassandra; Abert Vian, Maryline; Zemb, Thomas; Kunz, Werner; Chemat, Farid


    Bligh and Dyer (B & D) or Folch procedures for the extraction and separation of lipids from microorganisms and biological tissues using chloroform/methanol/water have been used tens of thousands of times and are "gold standards" for the analysis of extracted lipids. Based on the Conductor-like Screening MOdel for realistic Solvatation (COSMO-RS), we select ethanol and ethyl acetate as being potentially suitable for the substitution of methanol and chloroform. We confirm this by performing solid-liquid extraction of yeast (Yarrowia lipolytica IFP29) and subsequent liquid-liquid partition-the two steps of routine extraction. For this purpose, we consider similar points in the ternary phase diagrams of water/methanol/chloroform and water/ethanol/ethyl acetate, both in the monophasic mixtures and in the liquid-liquid miscibility gap. Based on high performance thin-layer chromatography (HPTLC) to obtain the distribution of lipids classes, and gas chromatography coupled with a flame ionisation detector (GC/FID) to obtain fatty acid profiles, this greener solvents pair is found to be almost as effective as the classic methanol-chloroform couple in terms of efficiency and selectivity of lipids and non-lipid material. Moreover, using these bio-sourced solvents as an alternative system is shown to be as effective as the classical system in terms of the yield of lipids extracted from microorganism tissues, independently of their apparent hydrophilicity.

  17. Raman Spectrum Analysis on the Solid-Liquid Boundary Layer of BGO Crystal Growth

    ZHANG Xia; YIN Shao-Tang; WAN Song-Ming; YOU Jing-Lin; CHEN Hui; ZHAO Si-Jie; ZHANG Qing-Li


    We study the Raman spectra of Bi4Ge3O12 crystal at different temperatures, as well as its melt. The structure characters of the single crystal, melt and growth solid-liquid boundary layer of BGO are investigated by their high-temperature Raman spectra for the first time. The rule of structure change of BGO crystal with increasing temperature is analysed. The results show that there exists [GeO4] polyhedral structure and Bi ion independently in BGO melt. The bridge bonds Bi-O-Bi and Bi-O-Ge appear in the crystal and at the boundary layer, but disappear in the melt. The structure of the growth solid-liquid boundary layer is similar to that of BGO crystal. In the melt, the long-range order structure of the crystal disappears. The thickness of the grovth solid-liquid boundary layer of BGO crystal is about 50 μm.

  18. Optimization of Solid-Liquid Extraction of Antioxidants from Black Mulberry Leaves by Response Surface Methodology

    Zoran Zeković


    Full Text Available The extraction of active components from natural sources depends on different factors. The knowledge of the effects of different extraction parameters is useful for the optimization of the process, as well for the ability to predict the extraction yield. The aim of this study is to examine the influence of solvent concentration (ethanol/water 40–80 %, by volume, temperature (40–80 °C and solvent/raw material ratio (10–30 mL/g on the extraction yield of phenolic compounds, flavonoids and antioxidant activity from black mulberry (Morus nigra L. leaves. Experimental values of total phenolic content were in the range from 18.6 to 48.7 mg of chlorogenic acid equivalents per g of dried leaves and total flavonoids in the range from 6.0 to 21.4 mg of rutin eqivalents per g of dried leaves. Antioxidant activity expressed as the inhibition concentration at 50 % (IC50 value was in the range from 0.019 to 0.078 mg of mulberry extract per mL. Response surface methodology (RSM was used to determine the optimum extraction conditions and to investigate the effect of different variables on the observed properties of mulberry leaf extracts. The results show a good fit to the proposed model (R˄2>0.90. The optimal conditions for obtaining the highest extraction yield of phenolics and flavonoids were within the experimental range. The experimental values agreed with those predicted, thus indicating suitability of the used model and the success of RSM in optimizing the investigated extraction conditions.

  19. Teaching Sustainable Development Concepts in the Laboratory: A Solid-Liquid Extraction Experiment

    Parajo, Juan Carlos; Dominguez, Herminia; Santos, Valentin; Alonso, Jose Luis; Garrote, Gil


    One of the principles of sustainable development is to replace chemicals traditionally derived from oil with alternative, renewable materials. For example, phenol and phenol derivatives currently used in the manufacture of wood adhesives can be replaced (at least in part) by biopolymers extracted from biomass. In this work, pine bark (a renewable…

  20. Analysis of Solid-Liquid Interface Behavior during Continuous Strip-Casting Process Using Sharp-Interface Technique

    Changbum Lee


    Full Text Available Continuous strip casting (CSC has been developed to fabricate thin metal plates while simultaneously controlling the microstructure of the product. A numerical analysis to understand the solid-liquid interface behaviors during CSC was carried out and used to identify the solidification morphologies of the plate, which were then used to obtain the optimum process conditions. In this study, we used a modified level contour reconstruction method and the sharp-interface method to modify the interface tracking, and we performed a simulation analysis to identify the differences in the material properties that affect the interface behavior. The effects of the process parameters such as the heat transfer coefficient and extrusion velocity on the behavior of the solid-liquid interface are estimated and also used to improve the CSC process.

  1. Development of a Sustainable Process for the Solid-Liquid Extraction of Antioxidants from Oat

    Raul Orozco-Mena


    Full Text Available This research paper studies the development of a sustainable process for the extraction of antioxidants from oat. Experimentation covered two factorials to evaluate significance among temperature, time, particle size and solvent. Total polyphenolic content (TPC and oxygen radical absorbance capacity (ORAC were the response variables. ANOVA was applied to find significance among variables and predict optimum conditions though a regression model. Extractions at different solid/solvent ratios were developed to study solvents’ solubility. Process simulation in Aspen Process Developer was carried out to evaluate energy cost, raw material cost, campaign time, and process mass intensity. Solvent and particle size showed significance as main effects, whereas temperature and time presented significance as interactions. From an industrial and sustainable perspective, ethanol (EtOH in a 1/20 (w/v ratio was the best choice since it presented the lowest cost for energy and raw material. It also showed the lowest process mass intensity (PMI, short campaign time, highest g extract/g oat, and a considerable antioxidant capacity.

  2. Determination of caffeoylquinic acids in feed and related products by focused ultrasound solid-liquid extraction and ultra-high performance liquid chromatography-mass spectrometry.

    Tena, M T; Martínez-Moral, M P; Cardozo, P W


    A method to determine caffeoylquinic acids (CQAs) in three sources (herbal extract, feed additive and finished feed) using for the first time focused ultrasound solid-liquid extraction (FUSLE) followed by ultra-high performance liquid chromatography (UPLC) coupled to quadrupole-time of flight mass spectrometry is presented. Pressurized liquid extraction (PLE) was also tested as extraction technique but it was discarded because cynarin was not stable under temperature values used in PLE. The separation of the CQAs isomers was carried out in only seven minutes. FUSLE variables such as extraction solvent, power and time were optimized by a central composite design. Under optimal conditions, FUSLE extraction was performed with 8mL of an 83:17 methanol-water mixture for 30s at a power of 60%. Only two extraction steps were found necessary to recover analytes quantitatively. Sensitivity, linearity, accuracy and precision were established. Matrix effect was studied for each type of sample. It was not detected for mono-CQAs, whereas the cynarin signal was strongly decreased due to ionization suppression in presence of matrix components; so the quantification by standard addition was mandatory for the determination of di-caffeoylquinic acids. Finally, the method was applied to the analysis of herbal extracts, feed additives and finished feed. In all samples, chlorogenic acid was the predominant CQA, followed by criptochlorogenic acid, neochlorogenic acid and cynarin. The method allows an efficient determination of chlorogenic acid with good recovery rates. Therefore, it may be used for screening of raw material and for process and quality control in feed manufacture.

  3. Solid-liquid extraction of alkali metals and organic compounds by leaching of food industry residues.

    Yu, Chaowei; Zheng, Yi; Cheng, Yu-Shen; Jenkins, Bryan M; Zhang, Ruihong; VanderGheynst, Jean S


    Leaching was studied for its application in extracting inorganic and organic constituents from fresh fermented grape pomace, air-dried fermented grape pomace and air-dried sugar beet pulp. Samples of each feedstock were leached in water at ambient temperature for 30 or 120 min at dry solid-to-liquid ratios of 1/20 and 1/50 kg/L. Leaching removed 82% of sodium, 86% of potassium, and 76% of chlorine from sugar beet pulp, and reduced total ash concentration in air-dry fermented grape pomace from 8.2% to 2.9% of dry matter, 8.2% to 4.4% in fresh fermented grape pomace, and 12.5% to 5.4% in sugar beet pulp. Glycerol (7-11 mg/dry g), ethanol (131-158 mg/dry g), and acetic acid (24-31 mg/dry g) were also extracted from fermented grape pomace. These results indicate that leaching is a beneficial pretreatment step for improving the quality of food processing residues for thermochemical and biochemical conversion.

  4. Performance analysis on solid-liquid mixed flow in a centrifugal pump

    Ning, C.; Wang, Y.


    In order to study the solid-liquid mixed flow hydraulic characteristics of centrifugal pump, the Pro/E software was used for three-dimensional modeling of centrifugal pump chamber. By using the computational fluid dynamics software CFX, the numerical simulation calculation of solid-liquid two-phase flow within whole flow passage of centrifugal pump was conducted. Aim at different particle diameters, the Reynolds-averaged N-S equations with the RNG k-Ɛ turbulence model and SIMPLEC algorithm were used to simulate the two-phase flow respectively on the condition of different volume fraction. The influence of internal flow characteristic on pump performance was analyzed. On the conditions of different particle diameter and different volume fraction, the turbulence kinetic energy and particle concentration are analyzed. It can be found that the erosion velocity ratio on the flow channel wall increases along with the increasing of the volume fraction

  5. Focused ultrasound solid-liquid extraction and selective pressurised liquid extraction to determine bisphenol A and alkylphenols in sewage sludge by gas chromatography-mass spectrometry.

    Martínez-Moral, María P; Tena, María T


    A new method for determining endocrine disrupter compounds (EDCs) in sewage sludge is described in this paper. EDCs studied were bisphenol A (BPA) and alkylphenols (APs). In order to obtain a fast and simple method, selective pressurised liquid extraction (SPLE) and focused ultrasound solid-liquid extraction (FUSLE) were tested. Best results for SPLE were obtained using Florisil as clean-up sorbent and dichloromethane as extraction solvent, while temperature was the only significant variable. Analyte extraction by SPLE was completed in only one extraction cycle of 1 min at 130 °C. FUSLE was carried out in one step of 20 s at 75% power (0.5 cycles) and with 8 mL of ethyl acetate. Although the optimised FUSLE process was faster, simpler and cheaper, SPLE provided higher recovery values (ranging from 81 to 105%) and therefore SPLE-based method was selected and validated. The SPLE and GC-MS method showed an LOD of 10.7 ng/g for BPA and LODs between 1.2 and 41.6 ng/g for APs. Relative standard deviation values lower than 6% were obtained for all analytes. As a result, an efficient, fast and simple method based on SPLE and GC-MS for the determination of BPA and APs in sewage sludge is proposed.

  6. Comparison between 2 methods of solid-liquid extraction for the production of Cinchona calisaya elixir: an experimental kinetics and numerical modeling approach.

    Naviglio, Daniele; Formato, Andrea; Gallo, Monica


    The purpose of this study is to compare the extraction process for the production of China elixir starting from the same vegetable mixture, as performed by conventional maceration or a cyclically pressurized extraction process (rapid solid-liquid dynamic extraction) using the Naviglio Extractor. Dry residue was used as a marker for the kinetics of the extraction process because it was proportional to the amount of active principles extracted and, therefore, to their total concentration in the solution. UV spectra of the hydroalcoholic extracts allowed for the identification of the predominant chemical species in the extracts, while the organoleptic tests carried out on the final product provided an indication of the acceptance of the beverage and highlighted features that were not detectable by instrumental analytical techniques. In addition, a numerical simulation of the process has been performed, obtaining useful information about the timing of the process (time history) as well as its mathematical description.

  7. Rapid Solid-Liquid Dynamic Extraction (RSLDE): a New Rapid and Greener Method for Extracting Two Steviol Glycosides (Stevioside and Rebaudioside A) from Stevia Leaves.

    Gallo, Monica; Vitulano, Manuela; Andolfi, Anna; DellaGreca, Marina; Conte, Esterina; Ciaravolo, Martina; Naviglio, Daniele


    Stevioside and rebaudioside A are the main diterpene glycosides present in the leaves of the Stevia rebaudiana plant, which is used in the production of foods and low-calorie beverages. The difficulties associated with their extraction and purification are currently a problem for the food processing industries. The objective of this study was to develop an effective and economically viable method to obtain a high-quality product while trying to overcome the disadvantages derived from the conventional transformation processes. For this reason, extractions were carried out using a conventional maceration (CM) and a cyclically pressurized extraction known as rapid solid-liquid dynamic extraction (RSLDE) by the Naviglio extractor (NE). After only 20 min of extraction using the NE, a quantity of rebaudioside A and stevioside equal to 1197.8 and 413.6 mg/L was obtained, respectively, while for the CM, the optimum time was 90 min. From the results, it can be stated that the extraction process by NE and its subsequent purification developed in this study is a simple, economical, environmentally friendly method for producing steviol glycosides. Therefore, this method constitutes a valid alternative to conventional extraction by reducing the extraction time and the consumption of toxic solvents and favouring the use of the extracted metabolites as food additives and/or nutraceuticals. As an added value and of local interest, the experiment was carried out on stevia leaves from the Benevento area (Italy), where a high content of rebaudioside A was observed, which exhibits a sweet taste compared to stevioside, which has a significant bitter aftertaste.

  8. Impact of ultrasound on solid-liquid extraction of phenolic compounds from maritime pine sawdust waste. Kinetics, optimization and large scale experiments.

    Meullemiestre, A; Petitcolas, E; Maache-Rezzoug, Z; Chemat, F; Rezzoug, S A


    Maritime pine sawdust, a by-product from industry of wood transformation, has been investigated as a potential source of polyphenols which were extracted by ultrasound-assisted maceration (UAM). UAM was optimized for enhancing extraction efficiency of polyphenols and reducing time-consuming. In a first time, a preliminary study was carried out to optimize the solid/liquid ratio (6g of dry material per mL) and the particle size (0.26 cm(2)) by conventional maceration (CVM). Under these conditions, the optimum conditions for polyphenols extraction by UAM, obtained by response surface methodology, were 0.67 W/cm(2) for the ultrasonic intensity (UI), 40°C for the processing temperature (T) and 43 min for the sonication time (t). UAM was compared with CVM, the results showed that the quantity of polyphenols was improved by 40% (342.4 and 233.5mg of catechin equivalent per 100g of dry basis, respectively for UAM and CVM). A multistage cross-current extraction procedure allowed evaluating the real impact of UAM on the solid-liquid extraction enhancement. The potential industrialization of this procedure was implemented through a transition from a lab sonicated reactor (3 L) to a large scale one with 30 L volume.

  9. Determination of endocrine disrupting compounds in fish liver, brain, and muscle using focused ultrasound solid-liquid extraction and dispersive solid phase extraction as clean-up strategy.

    Ros, Oihana; Vallejo, Asier; Olivares, Maitane; Etxebarria, Nestor; Prieto, Ailette


    This study describes a new method for the simultaneous extraction of several endocrine disrupting compounds, including alkylphenols (APs), estrogen, bisphenol-A (BPA) and one phthalate metabolite (mono-2-ethylhexyl ester, MEHP) in fish liver, brain, and muscle. Parameters affecting the extraction (extraction solvent and temperature) and the clean-up (dispersive phase nature and amount) steps were evaluated. The extraction was performed by means of focused ultrasound solid-liquid extraction (FUSLE) using 10 mL of n-hexane:acetone (50:50, v/v) for 5 min at ~0 °C, and the clean-up was done by means of dispersive solid phase extraction (dSPE) using 100 mg of ENVI-CARB and 100 mg of MgSO4 for the cleaning of brain and muscle extracts together with 100 mg of PSA in the case of liver extracts. Good apparent recoveries were obtained in the case of liver (62-132 %), brain (66-120 %), and muscle (74-129 %), relative standard deviation (RSD%) was always below 26 %, and the method detection limits (MDLs) were at low ng/g level. The developed method was applied to fish captured in Urdaibai estuary (Bay of Biscay) in December 2015, and the concentrations obtained were in the range MDL-1115 ng/g in brain, MDL-962 ng/g in muscle, and MDL-672 ng/g in liver. In general, the highest concentrations were measured in liver, followed by brain and muscle. In addition, diethylstilbestrol was only detected in fish brain. Graphical Abstract MS method scheme for the/MS method scheme for the determination of EDCs in fish liver, brain and muscle.

  10. Theoretical analysis and numerical computation of dilute solid/liquid two_phase pipe flow


    Starting with the kinetic theory for dilute solid/liquid two_phase flow, a mathematical model is established to predict the flow in a horizontal square pipe and the predictions are compared with LDV measurements. The present model predicts correctly two types of patterns of the vertical distribution of particle concentration observed in experiments, and also gives different patterns of the distribution of particle fluctuating energy. In the core region of the pipe, the predicted mean velocity of particles is smaller than that of liquid, but near the pipe bottom the reverse case occurs. In addition, full attention is paid to the mechanism for the vertical distribution of the average properties of particles such as concentration and mean velocity. From the kinetic_theory point of view, the cause of formation for different patterns of the vertical concentration distribution is not only related to the lift force exerted on a particle, but also related to the distribution of particle fluctuating energy.

  11. Numerical Thermodynamic Analysis of Two-Phase Solid-Liquid Abrasive Flow Polishing in U-Type Tube

    Junye Li


    Full Text Available U-type tubes are widely used in military and civilian fields and the quality of the internal surface of their channel often determines the merits and performance of a machine in which they are incorporated. Abrasive flow polishing is an effective method for improving the channel surface quality of a U-type tube. Using the results of a numerical analysis of the thermodynamic energy balance equation of a two-phase solid-liquid flow, we carried out numerical simulations of the heat transfer and surface processing characteristics of a two-phase solid-liquid abrasive flow polishing of a U-type tube. The distribution cloud of the changes in the inlet turbulent kinetic energy, turbulence intensity, turbulent viscosity, and dynamic pressure near the wall of the tube were obtained. The relationships between the temperature and the turbulent kinetic energy, between the turbulent kinetic energy and the velocity, and between the temperature and the processing velocity were also determined to develop a theoretical basis for controlling the quality of abrasive flow polishing.

  12. Analysis of solids, liquids, and biological tissues using solids probe introduction at atmospheric pressure on commercial LC/MS instruments.

    McEwen, Charles N; McKay, Richard G; Larsen, Barbara S


    Direct analysis of samples using atmospheric pressure ionization (API) provides a more rapid method for analysis of volatile and semivolatile compounds than vacuum solids probe methods and can be accomplished on commercial API mass spectrometers. With only a simple modification to either an electrospray (ESI) or atmospheric pressure chemical ionization (APCI) source, solid as well as liquid samples can be analyzed in seconds. The method acts as a fast solids/liquid probe introduction as well as an alternative to the new direct analysis in real time (DART) and desorption electrospray ionization (DESI) methods for many compound types. Vaporization of materials occurs in the hot nitrogen gas stream flowing from an ESI or APCI probe. Ionization of the thermally induced vapors occurs by corona discharge under standard APCI conditions. Accurate mass and mass-selected fragmentation are demonstrated as is the ability to obtain ions from biological tissue, currency, and other objects placed in the path of the hot nitrogen stream.

  13. Separation-preconcentration of nickel and lead in food samples by a combination of solid-liquid-solid dispersive extraction using SiO2 nanoparticles, ionic liquid-based dispersive liquid-liquid micro-extraction.

    Jalbani, Nusrat; Soylak, Mustafa


    A microextraction method for the determination of nickel and lead using solid-liquid-solid dispersive extraction followed by ionic liquid-based dispersive liquid-liquid microextraction (SLSDE-ILDLLME) was presented. It was applied to the extraction of nickel and lead from food samples. Ammonium pyrrolidine dithiocarbamate (APDC) as complexing agent, [C4MIM][PF6] as ionic liquid, SiO2 as nanoparticles and 2 mol L(-1) HNO3 as eluent were used. Several important parameters such as amount of IL, extraction time, pH and volume of the complexing agent were investigated. The quantitative recoveries were obtained at pH 7.0 for analytes. Under the optimum conditions, the limits of detection (LODs) calculated using 3(Sd)blank/m were 0.17 for Ni(II) and 0.79 µg L(-1) for Pb(II) for aqueous solutions with 125 enrichment factor (EF). The limit of detections of the analyte ions (3(Sd)blank/m) for solid samples were 0.09 µg g(-1) (Ni) and 0.40 µg g(-1) (Pb). The accuracy of the proposed method was confirmed by the analysis of standard reference material (1577c bovine liver) and spiked recovery test. The proposed method was applied to determine nickel and lead levels in chicken, fish and meat samples.

  14. Determination of spinosad at trace levels in bee pollen and beeswax with solid-liquid extraction and LC-ESI-MS.

    Yáñez, Karen P; Martín, María T; Bernal, José L; Nozal, María J; Bernal, José


    This paper reports the use of a new LC method with a fused-core analytical column coupled to ESI-MS to determine residues of the biopesticide spinosad in bee pollen and beeswax. The method analyzes the active ingredients, spinosyns A and D, with a simple and efficient sample treatment (recovery between 90 and 105%) consisting of a solid-liquid extraction with acetone (bee pollen) or acetonitrile (beeswax). The method was validated in terms of selectivity, LOD, LOQ, linearity, and precision. The LOD and LOQ values ranged between 0.1-0.2 and 0.4-0.7 μg/kg, respectively. Moreover, the precision obtained within the linear concentration range (LOQ 500 μg/kg) was satisfactory (RSD lower than 5%). Finally, the proposed method was applied to analyze bee pollen and beeswax samples collected from apiaries located close to fruit orchards in two Spanish regions.

  15. Ultrasound-assisted extraction of fructans from agave (Agave tequilana Weber var. azul at different ultrasound powers and solid-liquid ratios


    Full Text Available Abstract The effects of ultrasound-assisted extraction (UAE at different ultrasound power densities (UPDs; 40, 80, and 120 mW/mL and solid:liquid (S:L ratio (1:2, 1:3, and 1:6 on the extraction of carbohydrates from Agave tequilana plant of different ages were evaluated. Extracts obtained (6- and 7-year-old plant were analyzed in the yield of carbohydrates (YC, fructan (FRU content, simple sugars, fructan profile and the average degree of polymerization (DPn. UPD, S:L ratio, and plant age all affected YC, FRU, and DPn. Maximum YC and FRU were obtained from the older agave with UPD and S:L ratio of 120 mW/mL and 1:6, respectively; while glucose, fructose, and sucrose were highly released from the younger plant. Agave of 7-year-old presented the highest DPn. Fructan degradation occurred at high UPD, increasing the simple sugars and decreasing the DPn. Thermal-traditional extraction without sonication caused more fructan degradation; and overall, ultrasound enhanced fructan extraction and minimized fructan damage, representing a technological alternative for fructan extraction from agave.

  16. Solid-liquid extraction of Gd(Ⅲ) and separation possibilities of rare earths from phosphoric acid solutions using Tulsion CH-93 and Tulsion CH-90 resins

    S.Radhika; V.Nagaraju; B.Nagaphani Kumar; M.Lakshmi Kantam; B.Ramachandra Reddy


    Solid-liquid extraction of gadolinium was investigated from phosphoric acid medium using commercial amino phosphonic acid resin,Tulsion CH-93.The experimental conditions studied included equilibration time,acid concentration,mass of the resin,metal concentration,loading and elution.The percent extraction of Gd(Ⅲ) was studied as a function of phosphoric acid (0.05-3 mol/L) using Tulsion CH-93 resin.The corresponding lgD vs.equilibrium pH plot gave straight line with a slope of 1.8.The percent extraction decreased with acid concentration increasing,conforming ion exchange mechanism.Under observed experimental conditions the loading capacity of Tulsion CH-93 for gadolinium was 10.6 mg/g.Among several eluants screened,the quantitative elution of Gd(Ⅲ) from loaded Tulsion CH-93 was obtained with ammonium oxalate (0.15 mol/L).The extraction behavior of commonly associated metals with gadolinium was studied as a function of phosphoric acid concentration.Tulsion CH-93 resin showed selective extraction towards heavy rare earths (Lu and Yb) which could be separated from other rare earths at 3 mol/L H3PO4,similar to wet phosphoric acid (3-5 mol/L).On the other hand Gd(Ⅲ) and other rare earths were studied with chelating resin Tulsion CH-90.Light rare earths were highly extracted and these could be separated from heavy rare earths and Gd.

  17. Vortex-assisted matrix solid-liquid dispersive microextraction for the analysis of triazole fungicides in cotton seed and honeysuckle by gas chromatography.

    Xue, Jiaying; Li, Huichen; Liu, Fengmao; Jiang, Wenqing; Hou, Fan


    A one-step analytical method termed vortex-assisted matrix solid-liquid dispersive microextraction (VA-MSLDME) was developed for the determination of seven triazole fungicides from cotton seed and honeysuckle prior to gas chromatography with electron capture detection. The VA-MSLDME was performed by mixing the matrix, primary secondary amine, acetonitrile, toluene, and water in one single system. The target fungicides in the sample were extracted, cleaned up and preconcentrated simultaneously in the matrix/acetonitrile/water/toluene system. Meanwhile, the interferences were adsorbed by the cleanup adsorbent. The extraction recoveries of the fungicides from the samples varied from 82.9% to 97.8% with relative standard deviations of 4.4-8.5%. The enrichment factors of the analytes ranged from 22 to 47, and the limits of detection were in the range of 0.05-20 μg/kg. The results demonstrated the significant predominance of VA-MSLDME in the analysis of pesticide residues in cotton seed and honeysuckle samples.

  18. Organically modified silica with pyrazole-3-carbaldehyde as a new sorbent for solid-liquid extraction of heavy metals.

    Radi, Smaail; Tighadouini, Said; Bacquet, Maryse; Degoutin, Stéphanie; Cazier, Francine; Zaghrioui, Mustapha; Mabkhot, Yahia N


    A new chelating matrix, SiNP, has been prepared by immobilizing 1.5-dimethyl-1H-pyrazole-3-carbaldehyde on silica gel modified with 3-aminopropyl-trimethoxysilane. This new chelating material was well characterized by elemental analysis, FT-IR spectroscopy, cross polarization magic angle spinning solid state 13C-NMR, nitrogen adsorption-desorption isotherm, BET surface area, BJH pore size, and scanning electron microscopy (SEM). The new product exhibits good chemical and thermal stability as determined by thermogravimetry curves (TGA). The new prepared material was used as an adsorbent for the solid-phase extraction (SPE) of Pb(II), Cd(II), Cu(II) and Zn(II) from aqueous solutions using a batch method, prior to their determination by flame atomic adsorption spectrometry. The adsorption capacity was investigated using kinetics and pH effects. Common coexisting ions did not interfere with separation and determination.

  19. Development of an automated batch-type solid-liquid extraction apparatus and extraction of Zr, Hf, and Th by triisooctylamine from HCl solutions for chemistry of element 104, Rf

    Kasamatsu, Yoshitaka; Kino, Aiko; Yokokita, Takuya [Osaka Univ. (Japan). Graduate School of Science; and others


    Solid-liquid extraction of the group 4 elements Zr and Hf, which are homologues of Rf (Z = 104), and Th, a pseudo homologue, by triisooctylamine (TIOA) from HCl solutions was performed by batch method. After examining the time required to reach extraction equilibrium for these elements in various concentrations of TIOA and HCl, we investigated in detail variations in the distribution coefficients (K{sub d}) with TIOA and HCl concentrations. The K{sub d} values of Zr and Hf increased with increasing the HCl and TIOA concentrations, suggesting an increase in the abundance of the anionic chloride complexes of Zr and Hf. On the other hand, the K{sub d} values of Th were low in all the HCl concentrations studied, implying that Th does not form anionic species dominantly. We developed a new automated batch-type solid-liquid extraction apparatus for repetitive experiments on transactinide elements. Using this apparatus, we performed solid-liquid extraction employing the radioactive nuclides {sup 89m}Zr and {sup 175}Hf produced by nuclear reactions and transported continuously from the nuclear reaction chamber by the He/KCl gas-jet system. It was found that the distribution behaviors in 7-11 M HCl are almost constant in the time range 10-120 s, and the K{sub d} values are consistent with those obtained in the above manual experiment. This result suggests that the chemical reactions in the extraction process reach equilibrium within 10 s for Zr and Hf under the present experimental conditions. It took about 35 s for the extraction using the apparatus. These results indicate the applicability of the present extraction using the developed apparatus to {sup 261}Rf (T{sub 1/2} = 68 s) experiments.

  20. A novel extraction technique based on carbon nanotubes reinforced hollow fiber solid/liquid microextraction for the measurement of piroxicam and diclofenac combined with high performance liquid chromatography.

    Song, Xin-Yue; Shi, Yan-Ping; Chen, Juan


    A novel design of carbon nanotubes reinforced hollow fiber solid/liquid phase microextraction (CNTs-HF-SLPME) was developed to determine piroxicam and diclofenac in different real water samples. Functionalized multi-walled carbon nanotubes (MWCNTs) were held in the pores of hollow fiber with sol-gel technology. The pores and lumen of carbon nanotubes reinforced hollow fiber were subsequently filled with a μL volume of organic solvent (1-octanol), and then the whole assembly was used for the extraction of the target analytes in direct immersion sampling mode. The target analytes were extracted from the sample by two extractants, one of which is organic solvent placed inside the pores and lumen of hollow fiber and the other one is CNTs held in the pores of hollow fiber. After extraction, the analytes were desorbed in acetonitrile and analyzed using high performance liquid chromatography. This novel extraction mode showed more excellent extraction performance in comparison with conventional hollow fiber liquid microextraction (without adding CNTs) and carbon nanotubes reinforced hollow fiber solid microextraction (CNTs held in the pores of hollow fiber, but no organic solvents placed inside the lumen of hollow fiber) under the respective optimum conditions. This method provided 47- and 184-fold enrichment factors for piroxicam and diclofenac, respectively, good inter-fiber repeatability and batch-to-batch reproducibility. Linearity was observed in the range of 20-960 μg L(-1) for piroxicam, and 10-2560 μg L(-1) for diclofenac, with correlation coefficients of 0.9985 and 0.9989, respectively. The limits of detection were 4.58 μg L(-1) for piroxicam and 0.40 μg L(-1) for diclofenac.

  1. Organically modified silica with pyrazole-3-carbaldehyde as a new sorbent for solid-liquid extraction of heavy metals

    Radi, Smaail; Tighadouini, Said; Bacquet, Maryse; Degoutin, Stéphanie; Cazier, Francine; Zaghrioui, Mustapha; Mabkhot, Yahia N

    ...). The new prepared material was used as an adsorbent for the solid-phase extraction (SPE) of Pb(II), Cd(II), Cu(II) and Zn(II) from aqueous solutions using a batch method, prior to their determination by flame atomic adsorption spectrometry...

  2. Determination of bisphenol-type endocrine disrupting compounds in food-contact recycled-paper materials by focused ultrasonic solid-liquid extraction and ultra performance liquid chromatography-high resolution mass spectrometry.

    Pérez-Palacios, David; Fernández-Recio, Miguel Ángel; Moreta, Cristina; Tena, María Teresa


    Focused ultrasonic solid-liquid extraction (FUSLE) and reverse-phase ultra performance liquid chromatography (UPLC) coupled to a quadrupole-time of flight mass spectrometer (Q-TOF-MS) was applied to the determination of bisphenol-type endocrine disrupting compounds (EDCs) in food-contact recycled-paper materials. Recycled paper is a potential source of EDCs. Bisphenol A (BPA), bisphenol F (BPF) and their derivatives bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE) are used for the production of epoxy resins employed in the formulation of printing inks. The FUSLE of bisphenol-type EDCs from packaging is reported for the first time. First, different extraction solvents were studied and methanol was selected. Then, the main FUSLE factors affecting the extraction efficiency (solvent volume, extraction time and ultrasonic irradiation power) were studied by means of a central composite design. The FUSLE conditions selected for further experiments were 20 ml of methanol at ultrasonic amplitude of 100% for 5s. Finally, the number of extraction cycles necessary for complete extraction was established in two. The analysis of the FUSLE extracts was carried out by UPLC-Q-TOF-MS with electrospray ionization and the determination of the four analytes took place in only 4 min. The FUSLE and UPLC-ESI-QTOF-MS method was validated and applied to the analysis of different food-contact recycled-paper-based materials and packaging. The proposed method provided recoveries from 72% to 97%, repeatability and intermediate precision under 9% and 14%, respectively, and detection limits of 0.33, 0.16, 0.65 and 0.40 μg/g for BPA, BPF, BADGE and BFDGE, respectively. The analysis of paper and cardboard samples confirmed the presence of EDCs in these packaging.

  3. Numerical Simulation of 3D Solid-Liquid Turbulent Flow in a Low Specific Speed Centrifugal Pump: Flow Field Analysis

    Baocheng Shi


    Full Text Available For numerically simulating 3D solid-liquid turbulent flow in low specific speed centrifugal pumps, the iteration convergence problem caused by complex internal structure and high rotational speed of pump is always a problem for numeral simulation researchers. To solve this problem, the combination of three measures of dynamic underrelaxation factor adjustment, step method, and rotational velocity control means according to residual curves trends of operating parameters was used to improve the numerical convergence. Numeral simulation of 3D turbulent flow in a low specific speed solid-liquid centrifugal pump was performed, and the results showed that the improved solution strategy is greatly helpful to the numerical convergence. Moreover, the 3D turbulent flow fields in pumps have been simulated for the bottom ash-particles with the volume fraction of 10%, 20%, and 30% at the same particle diameter of 0.1 mm. The two-phase calculation results are compared with those of single-phase clean water flow. The calculated results gave the main region of the abrasion of the impeller and volute casing and improve the hydraulic design of the impeller in order to decrease the abrasion and increase the service life of the pump.

  4. Synthesis of 2, 6-Bis(1′-Phenyl-3′-Methyl-5′-Oxopyrazole-4′) Pyridinediacyl and Its Solid-Liquid Extraction Behavior for Ce(Ⅲ)

    邓启良; 郭效军; 彭波; 高锦章; 康敬万


    β-diketone type chelating ligands have high coordinative activity and selectivity, and are widely applied in analytical chemistry. In order to obtain profounder understanding to the properties of bis(4-acylpyrazolone-5), A new 4-acylpyrazol-5-one derivative (H2BPMPP) was syntheszed, which contains a heterocyclic ring between two 1-phenyl-3-methyl-4-acylpyrazol-5-one rings. The new compound was characterized by element analyses, UV, IR and 1H NMR spectra. The equilibrium of the keto-enol tautomerism was studied. The results show that a lower dielectric constant of solvent favors the enol form which has a higher λmax. Due to special merits of paraffin wax, the solid-liquid extraction behavior of Ce(Ⅲ) with molten paraffin wax as a diluent was also investigated at higher temperature. The value of the pH1/2 was 3.19 and the value of logKex was 3.467. The chemical composition of the complex was obtained by the slope analysis method.

  5. Numerical simulation analysis by solid-liquid coupling with 3DEC of dynamic water crannies in overlying strata

    MA Li-qiang; ZHANG Dong-sheng; JING Sheng-guo; ZHANG Wei; FAN Gang-wei


    To solve the problem of water loss during mining of shallow, buried coal seams, we have first analyzed the mechanism and suitability of solid-liquid coupling, i.e., we used the FLUID-MECHANICS system of 3-Dimensional Distinct Element Code(3DEC) in simulating dynamic water crannies in overlying strata, under mining conditions of a large longwall coalface. Next the dynamic initiation of a water cranny, its propagation and close phases were studied with 3DEC, along with the overlying strata breakage and recombination as the mining space of the shallow, buried coal seam increased. Combined with the change in the stress and displacement fields, the distribution features of the mining cranny were systematically studied. The effect of regularities and their effective measures of local filling and mine slicing technology in controlling mine crannies were investigated and the potential danger areas of water loss identified. Our results can be applied to decrease water loss during the exploitation of shallow, buried coal seams with a thin bedrock. The results also prove that 3DEC is a credible numerical analytical method to predict initiations of dynamic water crannies, their propagation, their closure phases and other concomitant hazards.

  6. Carbon nanotube reinforced hollow fiber solid/liquid phase microextraction: a novel extraction technique for the measurement of caffeic acid in Echinacea purpurea herbal extracts combined with high-performance liquid chromatography.

    Es'haghi, Zarrin; Golsefidi, Mazyar Ahmadi; Saify, Ali; Tanha, Ali Akbar; Rezaeifar, Zohre; Alian-Nezhadi, Zahra


    A new design of hollow fiber solid-liquid phase microextraction (HF-SLPME) was developed for the determination of caffeic acid in medicinal plants samples as Echinacea purpure. The membrane extraction with sorbent interface used in this research is a three-phase supported liquid membrane consisting of an aqueous (donor phase), organic solvent/nano sorbent (membrane) and aqueous (acceptor phase) system operated in direct immersion sampling mode. The multi-walled carbon nanotube dispersed in the organic solvent is held in the pores of a porous membrane supported by capillary forces and sonification. It is in contact with two aqueous phases: the donor phase, which is the aqueous sample, and the acceptor phase, usually an aqueous buffer. All microextraction experiments were supported using an Accurel Q3/2 polypropylene hollow fiber membrane (600 microm I.D., 200 microm wall thicknesses, and 0.2 microm pore size). The experimental setup is very simple and highly affordable. The hollow fiber is disposable, so single use of the fiber reduces the risk of cross-contamination and carry-over problems. The proposed method allows the very effective and enriched recuperation of an acidic analyte into one single extract. In order to obtain high enrichment and extraction efficiency of the analyte using this novel technique, the main parameters were optimized. Under the optimized extraction conditions, the method showed good linearity (0.0001-50 microg/L), repeatability, low limits of detection (0.00005 microg/L) and excellent enrichment (EF=2108). Copyright 2010 Elsevier B.V. All rights reserved.

  7. Simultaneous determination of four trace estrogens in feces, leachate, tap and groundwater using solid-liquid extraction/auto solid-phase extraction and high-performance liquid chromatography with fluorescence detection.

    Liu, Na; Shi, Yue-e; Li, Mengyan; Zhang, Ting-di; Gao, Song


    A simple and selective high-performance liquid chromatography method coupled with fluorescence detection was developed for the simultaneous measurement of trace levels of four estrogens (estrone, estradiol, estriol and 17α-ethynyl estradiol) in environmental matrices. For feces samples, solid-liquid extraction was applied with a 1:1 v/v mixture of acetonitrile and ethyl acetate as the extraction solvent. For liquid samples (e.g., leachate and groundwater), hydrophobic/lipophilic balanced automated solid-phase extraction disks were selected due to their high recoveries compared to conventional C18 disks. Chromatographic separations were performed on a reversed-phase C18 column gradient-eluted with a 45:55 v/v mixture of acetonitrile and water. The detection limits were down to 1.1 × 10(-2) (estrone), 4.11 × 10(-4) (estradiol), 5.2 × 10(-3) (estriol) and 7.18 × 10(-3) μg/L (17α-ethynyl estradiol) at excitation/emission wavelengths of 288/310 nm, with recoveries in the range of 96.9 ± 3.2-105.4 ± 3.2% (n = 3). The method was successfully applied to determine estrogens in feces and water samples collected at livestock farms and a major river in Northeast China. We observed relatively high abundance and widespread distribution of all four estrogens in our sample collections, implying the urgency for a comprehensive and intricate investigation of estrogenic fate and contamination in our researched area.

  8. Extraction and preconcentration of tylosin from milk samples through functionalized TiO₂ nanoparticles reinforced with a hollow fiber membrane as a novel solid/liquid-phase microextraction technique.

    Sehati, Negar; Dalali, Nasser; Soltanpour, Shahla; Dorraji, Mir Saeed Seyed


    The aim of this study was to introduce a novel, simple, and highly sensitive preparation method for determination of tylosin in different milk samples. In the so-called functionalized TiO2 hollow fiber solid/liquid-phase microextraction method, the acceptor phase is functionalized TiO2 nanoparticles that are dispersed in the organic solvent and held in the pores and lumen of a porous polypropylene hollow fiber membrane. An effective functionalization of TiO2 nanoparticles has been done in the presence of aqueous H2 O2 and a mild acidic ambient under UV irradiation. This novel extraction method showed excellent extraction efficiency and a high enrichment factor (540.2) in comparison with conventional hollow fiber liquid-phase microextraction. All the experiments were monitored at λmax = 284 nm using a simple double beam UV-visible spectrophotometer. A Taguchi orthogonal array experimental design with an OA16 (4(5) ) matrix was employed to optimize the factors affecting the efficiency of hollow fiber solid/liquid-phase microextraction such as pH, stirring rate, salt addition, extraction time, and the volume of donor phase. This developed method was successfully applied for the separation and determination of tylosin in milk samples with a linear concentration range of 0.51-7000 μg/L (r(2) = 0.991) and 0.21 μg/L as the limit of detection. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


    The use of solid-liquid phase transfer catalysis has an advantage of carrying out reaction between two immiscible substrates, one in solid phase and the other in liquid phase, with high selectivity and at relatively low temperatures. In this study we investigated the synthesis ci...

  10. Determination of cadmium and lead in urine samples after dispersive solid-liquid extraction on multiwalled carbon nanotubes by slurry sampling electrothermal atomic absorption spectrometry

    Álvarez Méndez, J.; Barciela García, J.; García Martín, S.; Peña Crecente, R. M.; Herrero Latorre, C.


    A new method for the determination of Cd and Pb in urine samples has been developed. The method involves dispersive solid-phase extraction (DSPE), slurry sampling (SS), and subsequent electrothermal atomic absorption spectrometry (ETAAS). Oxidized multiwalled carbon nanotubes (MWCNTs) were used as the sorbent material. The isolated MWCNT/analyte aggregates were treated with nitric acid to form a slurry and both metals were determined directly by injecting the slurry into the ETAAS-atomizer. The parameters that influence the adsorption of the metals on MWCNTs in the DSPE process, the formation and extraction of the slurry, and the ETAAS conditions were studied by different factorial design strategies. The detection and quantification limits obtained for Cd under optimized conditions were 9.7 and 32.3 ng L- 1, respectively, and for Pb these limits were 0.13 and 0.43 μg L- 1. The preconcentration factors achieved were 3.9 and 5.4. The RSD values (n = 10) were less than 4.1% and 5.9% for Cd and Pb, respectively. The accuracy of the method was assessed in recovery studies, with values in the range 96-102% obtained for Cd and 97-101% for Pb. In addition, the analysis of certified reference materials gave consistent results. The DSPE-SS-ETAAS method is a novel and useful strategy for the determination of Pb and Cd at low levels in human urine samples. The method is sensitive, fast, and free of matrix interferences, and it avoids the tedious and time-consuming on-column adsorption and elution steps associated with commonly used SPE procedures. The proposed method was used to determine Cd and Pb in urine samples of unexposed healthy people and satisfactory results were obtained.

  11. Intérêt des polymères à empreintes moléculaires pour la préparation d'échantillons par extraction solide-liquide.
    Applications aux triterpènes dans les plantes et aux dopants dans les urines.

    Claude, Bérengère


    This thesis reports results obtained with molecularly imprinted polymers (MIP) during solid-liquid extraction. The effects of various parameters (polymer-analyte interactions, composition of the sample matrix, extraction solvents polarity) on the selectivity and the capacity of the MIP have been studied.The first application has revealed the influence of hydrogen bonds during extraction of an organic sample with a MIP synthesized with methacrylic acid (MAA). Cross reactivity experiences perfo...

  12. β-Keto-enol Tethered Pyridine and Thiophene: Synthesis, Crystal Structure Determination and Its Organic Immobilization on Silica for Efficient Solid-Liquid Extraction of Heavy Metals.

    Radi, Smaail; Tighadouini, Said; Bacquet, Maryse; Degoutin, Stephanie; Dacquin, Jean-Philippe; Eddike, Driss; Tillard, Monique; Mabkhot, Yahia N


    Molecules bearing β-keto-enol functionality are potential candidates for coordination chemistry. Reported herein is the first synthesis and use of a novel designed ligand based on β-keto-enol group embedded with pyridine and thiophene moieties. The product was prepared in a one-step procedure by mixed Claisen condensation and was characterized by EA, m/z, FT-IR, (¹H, (13)C) NMR and single-crystal X-ray diffraction analysis. The new structure was grafted onto silica particles to afford a chelating matrix which was well-characterized by EA, FT-IR, solid-state (13)C-NMR, BET, BJH, SEM and TGA. The newly prepared organic-inorganic material was used as an adsorbent for efficient solid-phase extraction (SPE) of Cu(II), Zn(II), Cd(II) and Pb(II) from aqueous solutions and showed a capture capacity of 104.12 mg·g(-1), 98.90 mg·g(-1), 72.02 mg·g(-1), and 65.54 mg·g(-1), respectively. The adsorption capacity was investigated, in a batch method, using time of contact, pH, initial concentration, kinetics (Langmuir and Freundlich models), and thermodynamic parameters (ΔG°, ΔH° and ΔS°) of the system effects.

  13. Production of Valuable Lipophilic Compounds by Using Three Types of Interface Bioprocesses: Solid-Liquid Interface Bioreactor, Liquid-Liquid Interface Bioreactor, and Extractive Liquid-Surface Immobilization System.

    Oda, Shinobu


    Bioconversions such as enzymatic and microbial transformations are attractive alternatives to organic synthesis because of practical advantages such as resource conservation, energy efficiency, and environmentally harmonic properties. In addition, the production of secondary metabolites through microbial fermentation is also useful for manufacturing pharmaceuticals, agricultural chemicals, and aroma compounds. For microbial production of useful chemicals, the authors have developed three unique interfacial bioprocesses: a solid-liquid interface bioreactor (S/L-IBR), a liquid-liquid interface bioreactor (L/L-IBR), and an extractive liquid-surface immobilization (Ext-LSI) system. The S/L-IBR comprises a hydrophobic organic solvent (upper phase), a microbial film (middle phase), and a hydrophilic gel such as an agar plate (lower phase); the L/L-IBR and the Ext-LSI consist of a hydrophobic organic solvent (upper phase), a fungal mat with ballooned microspheres (middle phase), and a liquid medium (lower phase). All three systems have unique and practically important characteristics such as utilization of living cells, high concentration of lipophilic substrates/products in an organic phase, no requirement for aeration and agitation, efficient supply of oxygen, easy recovery of product, high regio- and stereoselectivity, and wide versatility. This paper reviews the principle, construction, characteristics, and application of these interfacial systems for producing lipophilic compounds such as useful aroma compounds, citronellol-related compounds, β-caryophyllene oxide, and 6-penty-α-pyrone.

  14. Spectrophotometric determination of copper in environmental samples by solid-liquid extraction of its 9, 10-phenanthrenequinone monoximate complex into molten naphthalene

    Wasey, A.; Puri, B.K.; Katyal, M.; Satake, M.


    A fairly selective and sensitive spectrophotometric method has been developed for determination of copper after extraction of its 9, 10-phenanthrenequinone monoximate complex into molten naphthalene in the pH range of 6.1-8.4. At room temperature, the solid naphthalene containing the metal complex is separated by filtration, dissolved in dimethylformamide (DMF) and the absorbance measured at 470 nm against the reagent blank. Beer's law is obeyed in the concentration range, 0.0-9.6 micrograms of copper in 10ml of DMF. The molar absorptivity and sensitivity are 6.30 X 10(4) 1 mol-1 cm-1 and 0.001 micrograms cm-2, respectively. The interference of various ions has been studied and the method has been applied for the determination of copper in various standard reference materials, beers, wines, human hair and environmental samples.

  15. Spectrophotometric determination of platinum after solid-liquid extraction with 1-(2-pyridylazo)-2-naphthol at 90°C

    DONG Yanjie; GAI Ke; GONG Xingxin


    An effective spectrophotometric determination of platinum with 1-(2-pyridylazo)-2-naphthol (PAN) using molten naphthalene as a diluent was studied. A green complex of platinum with PAN is formed at 90°C. In the range of pH 2.5-6.5,the complex is quantitatively extracted into molten naphthalene. The organic phase is anhydrously dissolved in CHC13 to be determined spectrophotometrically at 690 nm against the reagent blank. Beer's law is obeyed over the concentration range tively. The optimum conditions for determination are obtained. The interferences of various ions are observed in detail. The method has been applied to the determination of platinum in synthetic samples.

  16. Solid-liquid critical behavior of water in nanopores.

    Mochizuki, Kenji; Koga, Kenichiro


    Nanoconfined liquid water can transform into low-dimensional ices whose crystalline structures are dissimilar to any bulk ices and whose melting point may significantly rise with reducing the pore size, as revealed by computer simulation and confirmed by experiment. One of the intriguing, and as yet unresolved, questions concerns the observation that the liquid water may transform into a low-dimensional ice either via a first-order phase change or without any discontinuity in thermodynamic and dynamic properties, which suggests the existence of solid-liquid critical points in this class of nanoconfined systems. Here we explore the phase behavior of a model of water in carbon nanotubes in the temperature-pressure-diameter space by molecular dynamics simulation and provide unambiguous evidence to support solid-liquid critical phenomena of nanoconfined water. Solid-liquid first-order phase boundaries are determined by tracing spontaneous phase separation at various temperatures. All of the boundaries eventually cease to exist at the critical points and there appear loci of response function maxima, or the Widom lines, extending to the supercritical region. The finite-size scaling analysis of the density distribution supports the presence of both first-order and continuous phase changes between solid and liquid. At around the Widom line, there are microscopic domains of two phases, and continuous solid-liquid phase changes occur in such a way that the domains of one phase grow and those of the other evanesce as the thermodynamic state departs from the Widom line.

  17. Analysis by synchrotron X-ray radiography of convection effects on the dynamic evolution of the solid-liquid interface and on solute distribution during the initial transient of solidification

    Bogno, A., E-mail: [Aix Marseille Universite, Campus Saint-Jerome, Case 142, 13397 Marseille Cedex 20 (France); CNRS, UMR 6242, Campus Saint-Jerome, Case 142, 13397 Marseille Cedex 20 (France); Nguyen-Thi, H. [Aix Marseille Universite, Campus Saint-Jerome, Case 142, 13397 Marseille Cedex 20 (France); CNRS, UMR 6242, Campus Saint-Jerome, Case 142, 13397 Marseille Cedex 20 (France); Buffet, A. [ESRF, Avenue des Martyrs, BP 220, 38048 Grenoble Cedex (France); Reinhart, G.; Billia, B.; Mangelinck-Noel, N.; Bergeon, N. [Aix Marseille Universite, Campus Saint-Jerome, Case 142, 13397 Marseille Cedex 20 (France); CNRS, UMR 6242, Campus Saint-Jerome, Case 142, 13397 Marseille Cedex 20 (France); Baruchel, J. [ESRF, Avenue des Martyrs, BP 220, 38048 Grenoble Cedex (France); Schenk, T. [LPM - ENSMN, Parc de Saurupt, 54042 Nancy Cedex (France)


    In situ monitoring of the initial transient of directional solidification was carried out by means of synchrotron X-ray radiography. Experiments with Al-4 wt.% Cu alloy samples were performed on beamline ID19 of the European Synchrotron Radiation Facility (ESRF) in a dedicated Bridgman-type furnace. X-ray radiography enabled a detailed analysis of the evolution over time of the solid-liquid interface macroscopic shape in interaction with convection in the melt. Lateral solute segregation induced by fluid flow resulted in a significant deformation of the solid-liquid interface. The time-dependent velocity of the solidification front was determined at different abscissa values along the curved interface during the solidification process, from the growth phase with a smooth interface to the onset of morphological instability. Further, using a novel quantitative image analysis technique we were able to measure longitudinal solute profiles in the melt during the initial transient. Solutal length was then deduced as well as concentration in the melt, both at the interface and far away from it. The influence of convection on growth velocity and the characteristic parameters of the solute boundary layer are discussed, and a comparison with the Warren and Langer model is also presented.

  18. Perturbation theory of solid-liquid interfacial free energies of bcc metals.

    Warshavsky, Vadim B; Song, Xueyu


    A perturbation theory is used to calculate bcc solid-liquid interfacial free energies of metallic systems with embedded-atom model potentials. As a reference system for bcc crystals we used a single-occupancy cell, hard-sphere bcc system. Good agreements between the perturbation theory results and the corresponding results from simulations are found. The strategy to extract hard-sphere bcc solid-liquid interfacial free energies may have broader applications for other crystal lattices.

  19. Amino acids separation with the tetracarboxylic derived of the para-ter-butylcalix[4]arene by means of solid-liquid extraction assisted with lanthanides; Separacion de aminoacidos con el derivado tetracarboxilico del para-ter-butilcalix[4]areno mediante extraccion solido-liquido asistida con lantanidos

    Bernal R, R. del C.


    The tetracarboxylic derived of the para-ter-butylcalix[4]arene (B{sub 4}ACEbL{sup 4}) does not exist commercially for what was synthesized and characterized at laboratory level. The separation of the L-tyrosine amino acid was studied by means of a solid-liquid extraction system with the B{sub 4}ACEbL{sup 4} as solid phase, in function of ph (2.5-7.5) and contact time (5 and 15 hours) to temperature of 15-17 grades C. Resulted that the ph and the contact time were decisive in the extraction percentage of water tyrosine. The lowest percentage was 49% to ph 4 and the highest percentage was 61% to ph 7.5 with 15 hours of contact. In a contact time of 5 hours the extraction was inferior to 32% (ph 4) and of 47% to ph 6.5. The europium effect (Eu (III)) was studied to ph acid in the tyrosine separation and was found that the tyrosine extraction is not increased neither decomposes in europium presence, this is simultaneously extracted by the calixarene but it does not enter in competition for the calixarene with the amino acid. The separate solid phases: calixarene-tyrosine was analyzed by Far infrared radiation (Fir), Mid-Infrared (Mir) spectroscopy and luminescence to check the tyrosine presence in the separate solids as well as the nature of the connection calixarene-tyrosine. In this way was possible to check the tyrosine presence and to propose the formed molecular species tyrosine-calixarene, those which interact mainly by means of hydrogen connections and Van der Waals forces. The liquid phases before and after the extraction were analyzed by UV-Vis spectrophotometry and luminescence. The Neutron activation analysis was used to determine the europium content in the solid and liquid phases of extractions in europium presence. The tyrosine degradation also shows dependence with the ph, obtaining 88% degradation to the 24 hours to ph 7.5, while to ph 3 is degraded the 54% of tyrosine present in the sample. The europium presence does not affect the tyrosine extraction

  20. Binary Solid-Liquid Phase Equilibria

    Ellison, Herbert R.


    Indicates some of the information that may be obtained from a binary solid-liquid phase equilibria experiment and a method to write a computer program that will plot an ideal phase diagram to which the experimental results may be compared. (Author/CP)

  1. Solid-Liquid Interface Characterization Hardware

    Peters, Palmer N.


    The objective is to develop enabling technology to characterize the solid-liquid interface during directional solidification to unprecedented levels with real-time measurement hardware. Existing x-ray imaging hardware is combined with compact Seebeck furnaces and thermal profiling hardware, under development, to accomplish the measurements. Furnace thermal profiles are continuously measured in addition to the sample characteristics.



    The flow injection analysis was firstly used for studying a solid-liquid adsorption system,and the dynamics process in the adsorption of dyestuff with regenerable chitin was traced by an online method of flow injection-spectrophotometry. Experimental results indicate that there is a linearization between the tested signals and the height of peaks with reciprocity coefficient 0.9999by using the flow injection-spectrophotometry system to study the dynamics adsorption process in solid-liquid system. The method shows a good stability and reproducibility. It provides a new method for the studies on adsorption dynamics in solid- liquid system.

  3. Solid-liquid phase diagrams for the determination of the solid state nature of both polymorphs of (RS)-2-(2-oxo-pyrrolidin-1-yl)-butyramide.

    Herman, Christelle; Haut, Benoît; Aerts, Luc; Leyssens, Tom


    This work focuses on the determination of the solid state nature of (RS)-2-(2-oxo-pyrrolidin-1-yl)-butyramide (Etiracetam), the racemic intermediate of (S)-2-(2-oxo-pyrrolidin-1-yl)-butyramide, an Active Pharmaceutical Ingredient, marketed under the name Levetiracetam(®). It is show how this information can easily be extracted from solid-liquid phase diagrams of the racemic system. As two polymorphs of Etiracetam are known (Forms I and II), the analyses have been performed considering both polymorphs. The solid-liquid phase diagrams are determined experimentally, using Differential Scanning Calorimetry, and theoretically, using the Prigogine-Defay and Schroeder-Van Laar equations. Only the phase diagram involving the polymorph stable at higher temperatures (Form II) can be constructed experimentally. The theoretical phase diagram involving this polymorph compares well with the experimental one, thus allowing the use of theoretical equations for the prediction of the solid-liquid phase diagram involving Form I, which is meta-stable above 30.5 °C. Our findings confirm that both polymorphs are racemic compounds, which is also confirmed by XRPD analysis.

  4. A model of blind zone for in situ monitoring the solid/liquid interface using ultrasonic wave.

    Peng, Song; Ouyang, Qi; Zhu, Z Z; Zhang, X L


    To in situ monitor a solid/liquid interface to control metal qualities, the paper analysis blind models of the ultrasonic propagation in the solidifying molten metal with a solid/liquid interface in the Bridgman type furnace, and a mathematical calculation model of blind zone with different source locations and surface concavities is built. The study points out that the blind zone I is caused by ray bending in the interface edge, and the blind zone II is caused by totally reflection which is related with initial ray angle, critical refraction angle of solid/liquid media. A serial of simulation experiments are operated on the base of the model, and numerical computation results coincide with model calculated results very well. Therefore, receiver should locate beyond these blind zones in the right boundary to obtain time of flight data which is used to reconstruct the solid/liquid interface.

  5. Process optimization and analysis of microwave assisted extraction of pectin from dragon fruit peel.

    Thirugnanasambandham, K; Sivakumar, V; Prakash Maran, J


    Microwave assisted extraction (MAE) technique was employed for the extraction of pectin from dragon fruit peel. The extracting parameters were optimized by using four-variable-three-level Box-Behnken design (BBD) coupled with response surface methodology (RSM). RSM analysis indicated good correspondence between experimental and predicted values. 3D response surface plots were used to study the interactive effects of process variables on extraction of pectin. The optimum extraction conditions for the maximum yield of pectin were power of 400 W, temperature of 45 °C, extracting time of 20 min and solid-liquid ratio of 24 g/mL. Under these conditions, 7.5% of pectin was extracted. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. 气-固-液混凝土喷射机喷头结构的力学性能分析%Analysis of the Mechanics Characteristic in Gas-Solid-Liquid Concrete Jet Nozzle

    王金明; 谢旭时; 陈海; 叶谋平; 郭金基


    阐述气-固-液混凝土喷射机的结构,计算气-固-液流体的密度和质量流率,研究混合流体的动力学方程,讨论喷头结构对喷射性能的影响,最后介绍混凝土喷射机在建筑基坑边坡支护工程及喷锚网等的应用。%The structures of gas-solid-liquid concrete jet are described in this paper. The density and mass velocity of gas-solid-liquid fluid are calculated here. The equations of the mixed fluid dynamics are studied. The influences of the structures of nozzle on the jet characteristic are discussed. At last , the applications of the concrete jet in the brace engineering of constructional trench slope and jet anchored mesh etc. are introduced.

  7. 计入固液界面作用的润滑热力学模型与分析∗%Thermo dynamic analysis of lubrication considering solid-liquid interface interaction

    经昊达; 张向军; 田煜; 孟永钢


    Friction or lubrication process is a typical process of the energy dissipation. It can be reasonably described and speculated by using the entropy increase and dissipative structure theory of the non-equilibrium thermodynamics. In this paper, we model and analyze the typical thin-film lubrication mechanism based on the theory of thermodynamics, by using the interfacial disjoining pressure to characterize the dominant role of the solid-lubricant interaction on a microscale and establishing the lubrication Stribeck curve based on thermodynamic concepts. The concept of entropy production is adopted to describe the lubrication system, which is defined as the sum of multiplications of the thermodynamic forces and flows. Then the variations and the competing relations between the pairs of thermodynamic forces and flows could be used to reveal the different factors dominated in the lubrication system, such as the solid-liquid interaction, the sliding velocity, and the normal load. In this paper, we assume that all the dissipated energy caused by the viscous resistance of lubricant is converted into heat, then the total entropy increase per surface area at the frictional interface is considered, affected by interfacial disjoining pressure and the one-dimensional heat flow. With the entropy increasing analysis of lubrication process, we find that when the entropy production in the steady state becomes minimum, the total energy dissipation due to friction also becomes minimum, which directly indicates the lowest friction coefficient point at the lubrication Stribeck curve. Moreover, when a lubrication system loses its stability slightly from the equilibrium state, self-organization may occur at the solid-lubricant interface, thus resulting in partially ordering interfacial structures, which may indicate the interfacial structures when tribosystem turns from hydrodynamic lubrication phase into thin-film lubrication phase. In the experimental aspect, the location of the lowest

  8. Chemical Identification at the Solid-Liquid Interface.

    Söngen, Hagen; Marutschke, Christoph; Spijker, Peter; Holmgren, Eric; Hermes, Ilka; Bechstein, Ralf; Klassen, Stefanie; Tracey, John; Foster, Adam S; Kühnle, Angelika


    Solid-liquid interfaces are decisive for a wide range of natural and technological processes, including fields as diverse as geochemistry and environmental science as well as catalysis and corrosion protection. Dynamic atomic force microscopy nowadays provides unparalleled structural insights into solid-liquid interfaces, including the solvation structure above the surface. In contrast, chemical identification of individual interfacial atoms still remains a considerable challenge. So far, an identification of chemically alike atoms in a surface alloy has only been demonstrated under well-controlled ultrahigh vacuum conditions. In liquids, the recent advent of three-dimensional force mapping has opened the potential to discriminate between anionic and cationic surface species. However, a full chemical identification will also include the far more challenging situation of alike interfacial atoms (i.e., with the same net charge). Here we demonstrate the chemical identification capabilities of dynamic atomic force microscopy at solid-liquid interfaces by identifying Ca and Mg cations at the dolomite-water interface. Analyzing site-specific vertical positions of hydration layers and comparing them with molecular dynamics simulations unambiguously unravels the minute but decisive difference in ion hydration and provides a clear means for telling calcium and magnesium ions apart. Our work, thus, demonstrates the chemical identification capabilities of dynamic AFM at the solid-liquid interface.

  9. UV patterned nanoporous solid-liquid core waveguides

    Gopalakrishnan, Nimi; Sagar, Kaushal Shashikant; Christiansen, Mads Brøkner;


    Nanoporous Solid-Liquid core waveguides were prepared by UV induced surface modification of hydrophobic nanoporous polymers. With this method, the index contrast (delta n = 0.20) is a result of selective water infiltration. The waveguide core is defined by UV light, rendering the exposed part...

  10. Solid-liquid phase equilibria of Fe-Cr-Al alloys and spinels

    McMurray, J. W.; Hu, R.; Ushakov, S. V.; Shin, D.; Pint, B. A.; Terrani, K. A.; Navrotsky, A.


    Ferritic FeCrAl alloys are candidate accident tolerant cladding materials. There is a paucity of data concerning the melting behavior for FeCrAl and its oxides. Analysis tools have therefore had to utilize assumptions for simulations using FeCrAl cladding. The focus of this study is to examine in some detail the solid-liquid phase equilibria of FeCrAl alloys and spinels with the aim of improving the accuracy of severe accident scenario computational studies.

  11. Extraction of glabridin with heat reflux extraction by response surface analysis

    Li-ying DING


    Full Text Available Objective: To study the extraction process of glabridin from Glycyrrhiza glabra. Methods: The solid-liquid ratio, extraction time and extraction temperature are the three main factors in the experiment, and the extract solvent is ethyl acetate. Establish the response surface quadratic regression equation of glabridin extraction rate and purity. Results:The results indicate that the optimum conditions for glabridin are as follows: solvent is ethyl acetate, extraction time is 90 min, the ratio of solvent to solid is 35 ∶1 (ml/g, and extraction temperature is 44.7 ℃, purity and the maximum yield of Extraction of glabridin are 6.96% and 0.241%, The validation test shows that the experimental values of the model are 0.235% and 6.05% . Conclusion: The model equation can predict the experimental results, it can be used as reference in industrial production. 

  12. Optimization and validation of the solid-liquid extraction technique for determination of picloram in soils by high performance liquid chromatography Otimização e validação da técnica extração sólido-líquido para a determinação do picloram em solos por cromatografia líquida de alta eficiência

    E.C Assis


    Full Text Available The objective of this study was to optimize and validate the solid-liquid extraction (ESL technique for determination of picloram residues in soil samples. At the optimization stage, the optimal conditions for extraction of soil samples were determined using univariate analysis. Ratio soil/solution extraction, type and time of agitation, ionic strength and pH of extraction solution were evaluated. Based on the optimized parameters, the following method of extraction and analysis of picloram was developed: weigh 2.00 g of soil dried and sieved through a sieve mesh of 2.0 mm pore, add 20.0 mL of KCl concentration of 0.5 mol L-1, shake the bottle in the vortex for 10 seconds to form suspension and adjust to pH 7.00, with alkaline KOH 0.1 mol L-1. Homogenate the system in a shaker system for 60 minutes and then let it stand for 10 minutes. The bottles are centrifuged for 10 minutes at 3,500 rpm. After the settlement of the soil particles and cleaning of the supernatant extract, an aliquot is withdrawn and analyzed by high performance liquid chromatography. The optimized method was validated by determining the selectivity, linearity, detection and quantification limits, precision and accuracy. The ESL methodology was efficient for analysis of residues of the pesticides studied, with percentages of recovery above 90%. The limits of detection and quantification were 20.0 and 66.0 mg kg-1 soil for the PVA, and 40.0 and 132.0 mg kg-1 soil for the VLA. The coefficients of variation (CV were equal to 2.32 and 2.69 for PVA and TH soils, respectively. The methodology resulted in low organic solvent consumption and cleaner extracts, as well as no purification steps for chromatographic analysis were required. The parameters evaluated in the validation process indicated that the ESL methodology is efficient for the extraction of picloram residues in soils, with low limits of detection and quantification.O objetivo deste trabalho foi otimizar e validar a t

  13. Modelling temperature and concentration dependent solid/liquid interfacial energies

    Lippmann, Stephanie; Jung, In-Ho; Paliwal, Manas; Rettenmayr, Markus


    Models for the prediction of the solid/liquid interfacial energy in pure substances and binary alloys, respectively, are reviewed and extended regarding the temperature and concentration dependence of the required thermodynamic entities. A CALPHAD-type thermodynamic database is used to introduce temperature and concentration dependent melting enthalpies and entropies for multicomponent alloys in the temperature range between liquidus and solidus. Several suitable models are extended and employed to calculate the temperature and concentration dependent interfacial energy for Al-FCC with their respective liquids and compared with experimental data.

  14. Granular Solid-liquid Transition: Experiment and Simulation

    Fei, M.; Xu, X.; Sun, Q.


    Granular media are amorphous materials, which differs from traditional solid or liquid. In different circumstance, granular behavior varies from solid-like to liquid-like, and the transitions between these regimes are always related to many complex natural progresses such as the failure of soil foundation and the occurrence of landslide and debris flow. The mechanic of elastic instability during the transition from solid-like to liquid-like regime, and the quantitative description of irreversible deformation during flow are the key problems to interpret these transition phenomena. In this work, we developed a continuum model with elastic stable condition and irreversible flow rule of granular material based on a thermal dynamical model, the Two-Granular-Temperature model (TGT). Since infinitesimal elastic deformation in solid-like regime and significant plastic large deformation in liquid-like regime can coexist in the granular solid-liquid transition process, the material point method (MPM) was used to build an effective numerical model. Collapse of rectangular granular pile contains both the transition from granular solid to granular liquid and the inverse process, thus in this work we carried out collapse experiment with clay particles, and simulated the experiment with our continuum model and an open-source DEM model YADE to study the transition processes. Results between experiment and simulations were compared and good agreements on collapse shape and velocity profiles were achieved, and the new model proposed in this work seems to work well on the description of granular solid-liquid transition.

  15. Dynamic data evaluation for solid-liquid equilibria

    Cunico, Larissa; Ceriani, Roberta; Kang, Jeong Won

    The accuracy and reliability of the measured data sets to be used in regression of model parameters is an important issue related to modeling of phase equilibria. It is clear that good parameters for any model cannot be obtained from low quality data. A thermodynamic consistency test for solid-liquid...... systems using a relation between the solid and liquid activity coefficients for systems containing metals [1], where the data from the two phases are given were proposed. However, as consistency tests based on the Gibbs–Duhem equation are not feasible, new consistency tests have been developed [2]. Some...... of the developed tests were based in the quality tests proposed for VLE data by Kang et al. [3] and a methodology that combines solute activity coefficients in the liquid phase at infinite dilution and a theoretically based term to account for the non-ideality in dilute solutions are discussed. In this work, case...

  16. Solid/liquid interfacial free energies in binary systems

    Nason, D.; Tiller, W. A.


    Description of a semiquantitative technique for predicting the segregation characteristics of smooth interfaces between binary solid and liquid solutions in terms of readily available thermodynamic parameters of the bulk solutions. A lattice-liquid interfacial model and a pair-bonded regular solution model are employed in the treatment with an accommodation for liquid interfacial entropy. The method is used to calculate the interfacial segregation and the free energy of segregation for solid-liquid interfaces between binary solutions for the (111) boundary of fcc crystals. The zone of compositional transition across the interface is shown to be on the order of a few atomic layers in width, being moderately narrower for ideal solutions. The free energy of the segregated interface depends primarily upon the solid composition and the heats of fusion of the component atoms, the composition difference of the solutions, and the difference of the heats of mixing of the solutions.

  17. Solid-liquid separation in the mining industry

    Concha A , Fernando


    This book covers virtually all of the engineering science and technological aspects of separating water from particulate solids in the mining industry. It starts with an introduction to the field of mineral processing and the importance of water in mineral concentrators. The consumption of water in the various stages of concentration is discussed, as is the necessity of recovering the majority of that water for recycling. The book presents the fundamentals under which processes of solid-liquid separation are studied, approaching mixtures of discrete finely divided solid particles in water as a basis for dealing with sedimentation in particulate systems. Suspensions, treated as continuous media, provide the basis of sedimentation, flows through porous media and filtration. The book also considers particle aggregations, and thickening is analyzed in depth. Lastly, two chapters cover the fundamentals and application of rheology and the transport of suspensions.  This work is suitable for researchers and profess...

  18. Solid-liquid equilibrium of triolein with fatty alcohols

    G. J. Maximo


    Full Text Available Triacylglycerols and fatty alcohols are used in the formulation of cosmetic, pharmaceutical and food products. Although information about the phase transitions of these compounds and their mixtures is frequently required for design and optimization of processes and product formulation involving these substances, these data are still scarce in the literature. In the present study, the solid-liquid phase diagrams of two binary systems composed of triolein + 1-hexadecanol and triolein + 1-octadecanol were evaluated by differential scanning calorimetry (DSC and optical microscopy. The experimental data were compared with predicted data by solving the phase equilibrium equations using an algorithm implemented in MATLAB. The liquid-phase activity coefficients were calculated using the Margules equation (two- and three-suffix and the UNIFAC model (original and modified Dortmund model. The approaches used for calculating system equilibrium allowed an accurate prediction of the liquidus line with low deviations from the experimental data.

  19. Mathematical Modelling of Particle Movement Ahead of the Solid-liquid Interface in Continuous Casting


    Whether the particle will be trapped by the solid-liquid interface or not is dependent on its moving behavior ahead of theinterface, so a mathematical model has been developed to investigate the movement of the particle ahead of the solid-liquidinterface. Based on the theory for the boundary layer, the fluid velocity field near the solid-liquid interface was obtained, andthe trajectories of particles were calculated by the equations of motion for particles. In this model, the drag force, the addedmass force, the buoyance force, the gravitational force, the Saffman force and the Basset history force are considered. Theresults show that the behavior of the particle ahead of the solid-liquid interface is affected by the physical property of theparticle and fluid flow. And in the continuous casting process, if it moves in the stream directed upward or downward nearvertical solid-liquid interface or in the horizontal flow under the solid-liquid interface, the particle with the diameter from 5μmto 60 μm can reach the solid-liquid interface. But if it moves in horizontal flow above the solid-liquid interface, only theparticle with the diameter from 5μm to 10μm can reach the solid-liquid interface.

  20. Transient state study of electric motor heating and phase change solid-liquid cooling

    Bellettre, J.; Sartre, V.; Lallemand, A. [Centre National de la Recherche Scientifique (CNRS), Centre de Thermique de Lyon, Villeurbanne, 69 (France); Biais, F. [AUXILEC, Chatou, 78 (France)


    This study reports on modelling of an autosynchronous electric motor stator, operating at transient state. The developed model, of the modal type, includes around 20 nodes. The simulations showed that hot spots are localized on the winding heads and led to the choice of a solid-liquid phase change cooling system. The comparison between simulation and experiment permitted the identification of unknown parameters. The model gives a good accuracy during steady-state and in the rising temperature phase. The modelling of the phase change cooling is realized by the addition of two nodes. The sensitivity analysis to PCM properties shows that the hot spot temperature decreases with increasing conductivities, inertia and latent heat of melting of the PCM and with decreasing melting temperature. Gallium (metal melting at 30{sup o}C) is the best PCM for the cooling of hot spots and P116 paraffin is the best non-metallic PCM. (author)

  1. Heat Transfer Research of Gas-solid-liquid Three Phase Coupling of EGR Cooler

    Fu-Wu Yan


    Full Text Available The main aim of the study is to get the temperature and backpressure of a car engine exhaust gas which goes through the EGR-cooler. So the internal fluid flow and heat transfer process of the EGR cooler must be studied more clearly, numerical simulations are applied. Based on the strong coupling method, gas-solid-liquid three phases coupling model of the typical heat transfer unit is established. According to the coupling result, the heat flux of the tube’s outside surface is gained and then mapped to the inner surface of the cooler’s water. The water model is set up based on the separation coupling method. According to the analysis of the calculation, the detailed pressure and temperature distribution of the gas, water and solid are obtained. From the distribution cloud, we know the changes of the parameters along the fluid flows streamline.

  2. Effects of Solid-Liquid Mixing on Microstructure of Semi-Solid A356 Aluminum Alloy

    Guo, H. M.; Wang, L. J.; Wang, Q.; Yang, X. J.


    The desired starting material for semi-solid processing is the semi-solid slurry in which the solid phase is present as fine and globular particles. A modified solid-liquid mixing (SLM) is reported wherein semi-solid slurry can be produced by mixing a solid alloy block into a liquid alloy, and mechanical vibration is utilized to enhance the mixing. Effects such as liquid alloy temperature, mass ratio, and mixing intensity on the microstructure and the cooling curves during SLM were evaluated. 2D and 3D microstructure analysis of treated A356 aluminum alloy shows that microstructure can be refined significantly with a considerable morphology change in primary Al phase. It is critical that the temperature of mixture after mixing is lower than its liquidus temperature to obtain a valid SLM process. Specially, mixing intensity is identified as a primary factor for a favorable microstructure of semi-solid slurry.

  3. Solid-Liquid Interface Characterization Hardware: Advanced Technology Development (ATD)

    Peters, Palmer N.; Sisk, R. C.; Sen, S.; Kaukler, W. F.; Curreri, Peter A.; Wang, F. C.; Rose, M. Franklin (Technical Monitor)


    This ATD has the goal of enabling the integration of three separate measurement techniques to characterize the solid-liquid interface of directionally solidified materials in real-time. Arrays of film-based metal thermocouple elements are under development along with compact Seebeck furnaces suitable for interfacing with separately developed X-ray Transmission Microscopes. Results of applying film arrays to furnace profiling are shown, demonstrating their ability to identify a previously undetected hardware flaw in the development of a second-generation compact furnace. Results of real-time furnace profiling also confirmed that the compact furnace design effectively isolates the temperature profiles in two halves of the furnace, a necessary feature. This isolation had only been inferred previously from the characteristics of Seebeck data reported. Results from a 24-thermocouple array successfully monitoring heating and isothermal cooling of a tin sample are shown. The importance of non-intrusion by the arrays, as well as furnace design, on the profiling of temperature gradients is illustrated with example measurements. Further developments underway for effectively combining all three measurements are assessed in terms of improved x-ray transmission, increased magnification, integral arrays with minimum intrusion, integral scales for velocity measurements and other features being incorporated into the third generation Seebeck furnace under construction.

  4. Advanced Technology Development: Solid-Liquid Interface Characterization Hardware


    Characterizing the solid-liquid interface during directional solidification is key to understanding and improving material properties. The goal of this Advanced Technology Development (ATD) has been to develop hardware, which will enable real-time characterization of practical materials, such as aluminum (Al) alloys, to unprecedented levels. Required measurements include furnace and sample temperature gradients, undercooling at the growing interface, interface shape, or morphology, and furnace translation and sample growth rates (related). These and other parameters are correlated with each other and time. A major challenge was to design and develop all of the necessary hardware to measure the characteristics, nearly simultaneously, in a smaller integral furnace compatible with existing X-ray Transmission Microscopes, XTMs. Most of the desired goals have been accomplished through three generations of Seebeck furnace brassboards, several varieties of film thermocouple arrays, heaters, thermal modeling of the furnaces, and data acquisition and control (DAC) software. Presentations and publications have resulted from these activities, and proposals to use this hardware for further materials studies have been submitted as sequels to this last year of the ATD.

  5. Interaction of Porosity with a Planar Solid/Liquid Interface

    Catalina, Adrian V.; Stefanescu, Doru M.; Sen, Subhayu; Kaukler, William F.


    In this article, an investigation of the interaction between gas porosity and a planar solid/liquid (SL) interface is reported. A two-dimensional numerical model able to accurately track sharp SL interfaces during solidification of pure metals and alloys is proposed. The finite-difference method and a rectangular undeformed grid are used for computation. The SL interface is described through the points of intersection with the grid lines. Its motion is determined by the thermal and solute gradients at each particular point. Changes of the interface temperature because of capillarity or solute redistribution as well as any perturbation of the thermal and solute field produced by the presence of non-metallic inclusions can be computed. To validate the model, the dynamics of the interaction between a gas pore and a solidification front in metal alloys was observed using a state of the art X-ray transmission microscope (XTM). The experiments included observation of the distortion of the SL interface near a pore, real-time measurements of the growth rate, and the change in shape of the porosity during interaction with the SL interface in pure Al and Al-0.25 wt pct Au alloy. In addition, porosity-induced solute segregation patterns surrounding a pore were also quantified.

  6. Toward a detailed characterization of oil adsorbates as "solid liquids".

    Kutza, Claudia; Metz, Hendrik; Kutza, Johannes; Syrowatka, Frank; Mäder, Karsten


    Solid lipid formulation systems are used to overcome oral bioavailability problems of poorly water-soluble drugs. One promising process is the conversion of a liquid lipid system in a free flowing powder by use of adsorbing excipients. The aim of this study was the detailed characterization of solid-liquid interactions in oil adsorbed to Fujicalin and Neusilin which were manufactured by means of dual asymmetric centrifugation or conventional mortar/pestle blending. The adsorption strength of the excipients was investigated by Benchtop-NMR and ESR spectroscopy revealing the highest adsorption power for the Neusilin products. The adsorbate production methods as well as the storage of the excipients impact their adsorption properties. Environmental scanning electron microscopy (ESEM) and confocal laser scanning microscopy (CLSM) show that dual asymmetric centrifugation leads to a smoothing of the particle surface, whereas the mortar/pestle blending results in an uneven surface and particle destruction. The oil distribution at the particles is inhomogeneous for both production methods. The micropolarity of the adsorbed oil was investigated by ESR spectroscopy and multispectral fluorescence imaging. The adsorbing process on Neusilin leads to an increased micropolarity of the oil component. The release of the oil component in aqueous media could be verified by Benchtop-NMR and multispectral fluorescence imaging. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Computing equations of water hammer in pseudo-homogeneous solid-liquid flow and their verification


    In engineering practice, single-phase water hammer models are still employed to analyze the water hammer of solid-liquid flow. According to the characteristics of solid-liquid flow, continuity equations and momentum equations of pseudo-homogeneous flows are deduced, and a pseudo-homogeneous water hammer model is thus built and verified with experiment results. The characteristics of solid-liquid flow's viscosity, resistance and wave velocity are considered in the model. Therefore, it has higher precision than a single-phase model.

  8. Computing equations of water hammer in pseudo-homogeneous solid-liquid flow and their verification

    韩文亮; 董曾南; 柴宏恩; 韩军


    In engineering practice, single-phase water hammer models are still employed to analyze the water hammer of solid-liquid flow. According to the characteristics of solid-liquid flow, continuity equations and momentum equations of pseudo-homogeneous flows are deduced, and a pseudo-homogeneous water hammer model is thus built and verified with experiment results. The characteristics of solid-liquid flow’s viscosity, resistance and wave velocity are considered in the model. Therefore, it has higher precision than a single-phase model.

  9. Effect of current density on distribution coefficient of solute at solid-liquid interface

    常国威; 王自东; 吴春京; 胡汉起


    When current passes through the solid-liquid interface, the growth rate of crystal, solid-liquid interfaceenergy and radius of curvature at dendritic tip will change. Based on this fact, the theoretical relation between thedistribution of solute at solid-liquid interface and current density was established, and the effect of current on thedistribution coefficient of solute through effecting the rate of crystal growth, the solid-liquid interface energy and theradius of curvature at the dendritic tip was discussed. The results show that as the current density increases, thedistribution coefficient of solute tends to rise in a whole, and when the former is larger than about 400 A/cm2 , thelatter varies significantly.

  10. Quantitative Contact Resonance Force Microscopy for Viscoelastic Measurement of Soft Materials at the Solid-Liquid Interface.

    Churnside, Allison B; Tung, Ryan C; Killgore, Jason P


    Viscoelastic property measurements made at the solid-liquid interface are key to characterizing materials for a variety of biological and industrial applications. Further, nanostructured materials require nanoscale measurements. Here, material loss tangents (tan δ) were extracted from confounding liquid effects in nanoscale contact resonance force microscopy (CR-FM), an atomic force microscope based technique for observing mechanical properties of surfaces. Obtaining reliable CR-FM viscoelastic measurements in liquid is complicated by two effects. First, in liquid, spurious signals arise during cantilever excitation. Second, it is challenging to separate changes to cantilever behavior due to the sample from changes due to environmental damping and added mass effects. We overcame these challenges by applying photothermal cantilever excitation in multiple resonance modes and a predictive model for the hydrodynamic effects. We demonstrated quantitative, nanoscale viscoelastic CR-FM measurements of polymers at the solid-liquid interface. The technique is demonstrated on a point-by-point basis on polymer samples and while imaging in contact mode on a fixed plant cell wall. Values of tan δ for measurements made in water agreed with the values for measurements in air for some experimental conditions on polystyrene and for all examined conditions on polypropylene.

  11. Transformation of ferulic acid to vanillin using a fed-batch solid-liquid two-phase partitioning bioreactor.

    Ma, Xiao-kui; Daugulis, Andrew J


    Amycolatopsis sp. ATCC 39116 (formerly Streptomyces setonii) has shown promising results in converting ferulic acid (trans-4-hydroxy-3-methoxycinnamic acid; substrate), which can be derived from natural plant wastes, to vanillin (4-hydroxy-3-methoxybenzaldehyde). After exploring the influence of adding vanillin at different times during the growth cycle on cell growth and transformation performance of this strain and demonstrating the inhibitory effect of vanillin, a solid-liquid two-phase partitioning bioreactor (TPPB) system was used as an in situ product removal technique to enhance transformation productivity by this strain. The thermoplastic polymer Hytrel(®) G4078W was found to have superior partitioning capacity for vanillin with a partition coefficient of 12 and a low affinity for the substrate. A 3-L working volume solid-liquid fed-batch TPPB mode, using 300 g Hytrel G4078W as the sequestering phase, produced a final vanillin concentration of 19.5 g/L. The overall productivity of this reactor system was 450 mg/L. h, among the highest reported in literature. Vanillin was easily and quantitatively recovered from the polymers mostly by single stage extraction into methanol or other organic solvents used in food industry, simultaneously regenerating polymer beads for reuse. A polymer-liquid two phase bioreactor was again confirmed to easily outperform single phase systems that feature inhibitory or easily further degraded substrates/products. This enhancement strategy might reasonably be expected in the production of other flavor and fragrance compounds obtained by biotransformations.

  12. Numerical determination of the interfacial energy and nucleation barrier of curved solid-liquid interfaces in binary systems.

    Kundin, Julia; Choudhary, Muhammad Ajmal


    The phase-field crystal (PFC) technique is a widely used approach for modeling crystal growth phenomena with atomistic resolution on mesoscopic time scales. We use a two-dimensional PFC model for a binary system based on the work of Elder et al. [Phys. Rev. B 75, 064107 (2007)PRBMDO1098-012110.1103/PhysRevB.75.064107] to study the effect of the curved, diffuse solid-liquid interface on the interfacial energy as well as the nucleation barrier. The calculation of the interfacial energy and the nucleation barrier certainly depends on the proper definition of the solid-liquid dividing surface and the corresponding nucleus size. We define the position of the sharp interface at which the interfacial energy is to be evaluated by using the concept of equimolar dividing surface (r^{e}) and the minimization of the interfacial energy (r^{s}). The comparison of the results based on both radii shows that the difference r^{e}-r^{s} is always positive and has a limit for large cluster sizes which is comparable to the Tolman length. Furthermore, we found the real nucleation barrier for small cluster sizes, which is defined as a function of the radius r^{s}, and compared it with the classical nucleation theory. The simulation results also show that the extracted interfacial energy as function of both radii is independent of system size, and this dependence can be reasonably described by the nonclassical Tolman formula with a positive Tolman length.

  13. A novel application of microwave-assisted extraction of polyphenols from brewer's spent grain with HPLC-DAD-MS analysis.

    Moreira, Manuela M; Morais, Simone; Barros, Aquiles A; Delerue-Matos, Cristina; Guido, Luís F


    This paper reports a novel application of microwave-assisted extraction (MAE) of polyphenols from brewer's spent grains (BSG). A 2(4) orthogonal composite design was used to obtain the optimal conditions of MAE. The influence of the MAE operational parameters (extraction time, temperature, solvent volume and stirring speed) on the extraction yield of ferulic acid was investigated through response surface methodology. The results showed that the optimal conditions were 15 min extraction time, 100 °C extraction temperature, 20 mL of solvent, and maximum stirring speed. Under these conditions, the yield of ferulic acid was 1.31 ± 0.04% (w/w), which was fivefold higher than that obtained with conventional solid-liquid extraction techniques. The developed new extraction method considerably reduces extraction time, energy and solvent consumption, while generating fewer wastes. HPLC-DAD-MS analysis indicated that other hydroxycinnamic acids and several ferulic acid dehydrodimers, as well as one dehydrotrimer were also present, confirming that BSG is a valuable source of antioxidant compounds.

  14. Modeling the solid-liquid phase transition in saturated triglycerides

    Pink, David A.; Hanna, Charles B.; Sandt, Christophe; MacDonald, Adam J.; MacEachern, Ronald; Corkery, Robert; Rousseau, Dérick


    We investigated theoretically two competing published scenarios for the melting transition of the triglyceride trilaurin (TL): those of (1) Corkery et al. [Langmuir 23, 7241 (2007)], in which the average state of each TL molecule in the liquid phase is a discotic "Y" conformer whose three chains are dynamically twisted, with an average angle of ˜120° between them, and those of (2) Cebula et al. [J. Am. Oil Chem. Soc. 69, 130 (1992)], in which the liquid-state conformation of the TL molecule in the liquid phase is a nematic h∗-conformer whose three chains are in a modified "chair" conformation. We developed two competing models for the two scenarios, in which TL molecules are in a nematic compact-chair (or "h") conformation, with extended, possibly all-trans, chains at low-temperatures, and in either a Y conformation or an h∗ conformation in the liquid state at temperatures higher than the phase-transition temperature, T∗=319 K. We defined an h-Y model as a realization of the proposal of Corkery et al. [Langmuir 23, 7241 (2007)], and explored its predictions by mapping it onto an Ising model in a temperature-dependent field, performing a mean-field approximation, and calculating the transition enthalpy ΔH. We found that the most plausible realization of the h-Y model, as applied to the solid-liquid phase transition in TL, and likely to all saturated triglycerides, gave a value of ΔH in reasonable agreement with the experiment. We then defined an alternative h-h∗ model as a realization of the proposal of Cebula et al. [J. Am. Oil Chem. Soc. 69, 130 (1992)], in which the liquid phase exhibits an average symmetry breaking similar to an h conformation, but with twisted chains, to see whether it could describe the TL phase transition. The h-h∗ model gave a value of ΔH that was too small by a factor of ˜3-4. We also predicted the temperature dependence of the 1132 cm-1 Raman band for both models, and performed measurements of the ratios of three TL Raman

  15. Evaluation of the solid/liquid interface undercooling during Sn-Se Eutectic growth

    M. Zanotello


    Full Text Available The Sn-Se eutectic solidification allows one to obtain a lamellar structure, formed by SnSe and SnSe2 compounds, which are p and n semiconducting types, respectively. The SnSe-SnSe2 eutectic composite is a promising material to be used in photovoltaic device manufacturing. In a lamellar eutectic microstructure, the main parameter, which governs many of its characteristics, is the lamellar spacing. Such a parameter is primarily a result of the undercooling at the solid/liquid interface, which depends on the growth rate and the eutectic system properties. In this work, the Sn-Se alloy corresponding to eutectic composition was studied by using DSC thermal analysis and directional solidification at several growth rates in a vertical Bridgman-Stockbarger unit. The objective of the experiments was to investigate the influence of the growth rate on the growth undercooling, as well as on the eutectic microstructure. The microstructure analysis showed that a very regular and aligned structure formed by the SnSe and SnSe2 solid phases can be produced. By using the classic eutectic growth theory developed by Jackson and Hunt, the experimental results obtained led to the evaluation of a relationship among growth rates, eutectic growth temperature and lamellar spacing.

  16. The Little Heat Engine: Heat Transfer in Solids, Liquids and Gases

    Robitaille P.-M.


    Full Text Available In this work, an introductory exposition of the laws of thermodynamics and radiative heat transfer is presented while exploring the concepts of the ideal solid, the lattice, and the vibrational, translational, and rotational degrees of freedom. Analysis of heat transfer in this manner helps scientists to recognize that the laws of thermal radiation are strictly applicable only to the ideal solid. On the Earth, such a solid is best represented by either graphite or soot. Indeed, certain forms of graphite can approach perfect absorption over a relatively large frequency range. Nonetheless, in dealing with heat, solids will eventually sublime or melt. Similarly, liquids will give way to the gas phase. That thermal conductivity eventually decreases in the solid signals an inability to further dissipate heat and the coming breakdown of Planck’s law. Ultimately, this breakdown is reflected in the thermal emission of gases. Interestingly, total gaseous emissivity can de- crease with increasing temperature. Consequently, neither solids, liquids, or gases can maintain the behavior predicted by the laws of thermal emission. Since the laws of thermal emission are, in fact, not universal, the extension of these principles to non-solids constitutes a serious overextension of the work of Kirchhoff, Wien, Stefan and Planck.

  17. Effects of solid-liquid separation and storage on monensin attenuation in dairy waste management systems

    Hafner, Sarah C.; Watanabe, Naoko; Harter, Thomas; Bergamaschi, Brian; Parikh, Sanjai J.


    Environmental release of veterinary pharmaceuticals has been of regulatory concern for more than a decade. Monensin is a feed additive antibiotic that is prevalent throughout the dairy industry and is excreted in dairy waste. This study investigates the potential of dairy waste management practices to alter the amount of monensin available for release into the environment. Analysis of wastewater and groundwater from two dairy farms in California consistently concluded that monensin is most present in lagoon water and groundwater downgradient of lagoons. Since the lagoons represent a direct source of monensin to groundwater, the effect of waste management, by mechanical screen separation and lagoon aeration, on aqueous monensin concentration was investigated through construction of lagoon microcosms. The results indicate that monensin attenuation is not improved by increased solid-liquid separation prior to storage in lagoons, as monensin is rapidly desorbed after dilution with water. Monensin is also shown to be easily degraded in lagoon microcosms receiving aeration, but is relatively stable and available for leaching under typical anaerobic lagoon conditions.

  18. Effects of solid-liquid separation and storage on monensin attenuation in dairy waste management systems.

    Hafner, Sarah C; Watanabe, Naoko; Harter, Thomas; Bergamaschi, Brian A; Parikh, Sanjai J


    Environmental release of veterinary pharmaceuticals has been of regulatory concern for more than a decade. Monensin is a feed additive antibiotic that is prevalent throughout the dairy industry and is excreted in dairy waste. This study investigates the potential of dairy waste management practices to alter the amount of monensin available for release into the environment. Analysis of wastewater and groundwater from two dairy farms in California consistently concluded that monensin is most present in lagoon water and groundwater downgradient of lagoons. Since the lagoons represent a direct source of monensin to groundwater, the effect of waste management, by mechanical screen separation and lagoon aeration, on aqueous monensin concentration was investigated through construction of lagoon microcosms. The results indicate that monensin attenuation is not improved by increased solid-liquid separation prior to storage in lagoons, as monensin is rapidly desorbed after dilution with water. Monensin is also shown to be easily degraded in lagoon microcosms receiving aeration, but is relatively stable and available for leaching under typical anaerobic lagoon conditions.

  19. Solid-liquid reactions: The effect of Cu content on Sn-Ag-Cu interconnects

    Lu, Henry Y.; Balkan, Haluk; Simon, K. Y.


    The impact of copper content on the Sn-Ag-y%Cu (Ag=constant=3.5; y=0.0, 0.5, 1.0, and 2.0) interconnects was investigated in this study. The copper content and solid-liquid (S-L) reactions were used as inputs, and the outputs were the interfacial microstructure evolution and joint macro-performance. Surface microetching microscopy, cross-section microscopy, energy-dispersive x-ray analysis, shear test, and differential scanning calorimetry were used in the studies. It was discovered that as-soldered Sn-Ag-y%Cu interconnects could have different interfacial microstructures depending on copper content; no Ag3Sn plates were observed for any alloy groups. After the S-L reactions, Ag3Sn plates occurred for all groups. The magnitude of the Ag3Sn plate growth depended on copper content. This and other effects of copper content on Sn-Ag-Cu interconnects are discussed in this article.

  20. The contact line behaviour of solid-liquid-gas diffuse-interface models

    Sibley, David N; Savva, Nikos; Kalliadasis, Serafim


    A solid-liquid-gas moving contact line is considered through a diffuse-interface model with the classical boundary condition of no-slip at the solid surface. Examination of the asymptotic behaviour as the contact line is approached shows that the relaxation of the classical model of a sharp liquid-gas interface, whilst retaining the no-slip condition, resolves the stress and pressure singularities associated with the moving contact line problem while the fluid velocity is well defined (not multi-valued). The moving contact line behaviour is analysed for a general problem relevant for any density dependent dynamic viscosity and volume viscosity, and for general microscopic contact angle and double well free-energy forms. Away from the contact line, analysis of the diffuse-interface model shows that the Navier--Stokes equations and classical interfacial boundary conditions are obtained at leading order in the sharp-interface limit, justifying the creeping flow problem imposed in an intermediate region in the se...

  1. Microscopic thin film optical anisotropy imaging at the solid-liquid interface

    Miranda, Adelaide; De Beule, Pieter A. A.


    Optical anisotropy of thin films has been widely investigated through ellipsometry, whereby typically an optical signal is averaged over a ˜1 cm2 elliptical area that extends with increasing angle-of-incidence (AOI). Here, we report on spectroscopic imaging ellipsometry at the solid-liquid interface applied to a supported lipid bilayer (SLB). We detail how a differential spectrally resolved ellipsometry measurement, between samples with and without optically anisotropic thin film on an absorbing substrate, can be applied to recover in and out of plane refractive indices of the thin film with known film thickness, hence determining the thin film optical anisotropy. We also present how optimal wavelength and AOI settings can be determined ensuring low parameter cross correlation between the refractive indices to be determined from a differential measurement in Δ ellipsometry angle. Furthermore, we detail a Monte Carlo type analysis that allows one to determine the minimal required optical ellipsometry resolution to recover a given thin film anisotropy. We conclude by presenting a new setup for a spectroscopic imaging ellipsometry based on fiber supercontinuum laser technology, multi-wavelength diode system, and an improved liquid cell design, delivering a 5 ×-10 × ellipsometric noise reduction over state-of-the-art. We attribute this improvement to increased ellipsometer illumination power and a reduced light path in liquid through the use of a water dipping objective.

  2. Dynamic properties of the polyethylene glycol molecules on the oscillating solid-liquid interface.

    Yoshimoto, Minoru; Yuda, Yukiko; Aizawa, Hidenobu; Sato, Hiroaki; Kurosawa, Shigeru


    The dynamic properties of polyethylene glycol (PEG) molecules on the solid-liquid interface oscillating at MHz were investigated using the quartz crystal microbalance (QCM). The number-average molecular weights (M(n)) of the PEG molecules were systematically varied over 4 orders of magnitude. This study makes it clear that the series-resonant frequency shift, ΔF, of the QCM against the square root of the density-viscosity product of the PEG solution is linear and has the intercept. Moreover, systematical analysis reveals that the ΔF slope rapidly decreases with M(n) and that the ΔF intercept becomes constant above 4.0×10(3) g mol(-1). As a result, those reveal that the resonant length of the PEG molecule moving with the oscillating plate of 9 MHz is 54.2 Å. We also find that the behaviors of ΔF due to M(n) are mainly caused by the length of the PEG molecule. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Reaction mechanism of lanthanum nitrate-doped Mo-La material during solid-liquid spray doping processing

    Peng-Fa Feng; Qin-Li Yang; Xiao-Ming Dang; Sha Xi; Ya-Qi Wang


    At three critical temperatures which were obtained by thermo-gravimetry-differential thermal analysis-differential scanning calorimetry (TG/DTG/DSC)curves of lanthanum nitrate crystal,the air thermal decomposition experiments and solid-liquid spray doping simulation procedures of lanthanum nitrate crystal were carried out,and their products were analyzed by X-ray diffraction (XRD).Meanwhile,the spray doping processing of MoO2-50 wt% La(NO3)3 composite powder was undergone with lanthanum nitrate solution as the dopant,and doped MoO2 powder was analyzed by XRD.The results demonstrate that during the traditional solid-liquid spray doping processing,lanthanum nitrate,in the form of either crystal or aqueous solution,would be converted into La(NO3)3·4H2O by the dehydration reaction,rather than be decomposed to La2O3 and NO or NO2.Therefore,it is inferred that the oxynitride gas produced from the process is attributed to the decomposition of residual HNO3 in lanthanum nitrate crystal.The source of HNO3 is supported by the chemical composition of lanthanum nitrate crystal.

  4. Redistribution of fluorescent molecules at the solid/liquid interface with total internal reflection illumination.

    Wei, Lin; Ye, Zhongju; Luo, Wenjuan; Chen, Bo; Xiao, Lehui


    Many intriguing physical and chemical processes commonly take place at the solid/liquid interface. Total internal reflection illumination, together with single molecule spectroscopy, provides a robust platform for the selective exploration of kinetic processes close the interface. With these techniques, it was observed that the distribution of Rhodamine B molecules close to a solid/liquid interface could be regulated in a photo-induced route. The laser-induced repulsion force at this interface is enough to compromise the Brownian diffusion of single molecules in a range of several hundred nanometers normal to the solid/liquid interface. This observation is fundamentally and practically interesting because moderate laser intensity is enough to initiate this repulsion effect. Therefore, it might display extensive applications in the development of photo-modulation technique with high throughput capability.

  5. Understanding the lateral movement of particles adsorbed at a solid-liquid interface.

    Savaji, Kunal; Li, Xue; Couzis, Alexander


    In this paper we study the phenomenon of lateral movement of particles that are electrostatically adsorbed at a solid-liquid interface. The experimental system involves negatively charged silica particles of two different sizes (65 nm and 90 nm) that are exposed to the positively charged solid surface (silane coated silicon wafer) in sequential steps. The particle-adsorbed wafers are analyzed under a scanning electron microscope and the images are processed to determine the pair-correlation function for the particles adsorbed in the first step. From the pair correlation data and the particle surface coverage data we show that the adsorbed particles are mobile at the solid-liquid interface. In specific, we show that the adsorbed particles are mobile at the solid-liquid interface when there is a driving force for the adsorbed particles to move. The driving force in the scheme of experiments discussed in this paper is the reduction in the free energy of the system.

  6. Water hammer in coarse-grained solid-liquid flows in hydraulic hoisting for ocean mining

    韩文亮; 王光谦; 吴保生; 刘少军; 邹伟生


    The particles of polymetallic nodules in hydraulic hoisting flows that are used for mining in deep sea are rather coarse, therefore their flow velocity is smaller than that of the surrounding water. The characteristics of solid-liquid flows such as their density, concentration, elastic modulus and resistance were discussed. The wave propagation speed and the continuity and momentum equations of water hammer in coarse-grained solid-liquid flows were theoretically derived, and a water hammer model for such flows was developed.

  7. Rapid determination of methanol content in paper materials by alkaline extraction, coupled with headspace analysis.

    Zhang, Chun-Yun; Li, Ling-Ling; Chai, Xin-Sheng; Barnes, Donald G


    This study reports on a rapid method for the determination of methanol in paper-based materials by alkaline extraction, coupled with headspace analysis. Methanol partition equilibria between solid-liquid phases and vapor-liquid phases were conducted in two separate containers, from which an equation for calculating the total methanol content in the original paper sample was derived. It was found that the extraction equilibrium of methanol from solid sample could be achieved within 5min at room temperature using a high-speed disintegrator, and a subsequent neutralization step is an effective way to prevent methanol from being regenerated at high temperature during headspace equilibration. The results showed that the relative standard deviations for reproducibility tests were in the range of 1.86-6.03%, and the recoveries were in the range of 92.3-107%. The present method is simple and practical; it can be an efficient tool for quantifying the methanol content in paper-based materials and thus play an important role in the investigation of methanol migration behavior in food and beverage packaging.

  8. Non-equilibrium Thermodynamic Dissolution Theory for Multi-Component Solid/Liquid Surfaces Involving Surface Adsorption and Radiolysis Kinetics

    Stout, R B


    A theoretical expression is developed for the dissolution rate response for multi-component radioactive materials that have surface adsorption kinetics and radiolysis kinetics when wetted by a multi-component aqueous solution. An application for this type of dissolution response is the performance evaluation of multi-component spent nuclear fuels (SNFs) for long term interim storage and for geological disposition. Typically, SNF compositions depend on initial composition, uranium oxide and metal alloys being most common, and on reactor burnup which results in a wide range of fission product and actinide concentrations that decay by alpha, beta, and gamma radiation. These compositional/burnup ranges of SNFs, whether placed in interim storage or emplaced in a geologic repository, will potentially be wetted by multi-component aqueous solutions, and these solutions may be further altered by radiolytic aqueous species due to three radiation fields. The solid states of the SNFs are not thermodynamically stable when wetted and will dissolve, with or without radiolysis. The following development of a dissolution theory is based on a non-equilibrium thermodynamic analysis of energy reactions and energy transport across a solid-liquid phase change discontinuity that propagates at a quasi-steady, dissolution velocity. The integral form of the energy balance equation is used for this spatial surface discontinuity analysis. The integral formulation contains internal energy functional of classical thermodynamics for both the SNFs' solid state and surface adsorption species, and the adjacent liquid state, which includes radiolytic chemical species. The steady-state concentrations of radiolytic chemical species are expressed by an approximate analysis of the decay radiation transport equation. For purposes of illustration a modified Temkin adsorption isotherm was assumed for the surface adsorption kinetics on an arbitrary, finite area of the solid-liquid dissolution interface

  9. Extraction and elemental analysis of Coleus forskohlii extract

    Haritha Kanne


    Full Text Available Background: Coleus forskohlii Willd. is a popular traditional medicine used since ancient times for treatment of heart diseases, abdominal colic and respiratory disorders. Objective: The aim of this study was to characterize the root extract of the medicinal plant Coleus forskohlii. Materials and Methods: Dry roots of C. forskohlii were used to extract Forskolin using toluene as a solvent. Thus, obtained extract of C. forskohlii was standardized to 30% and used for further studies. Results: The physical properties of the extract were analyzed through scanning electron microscopy analysis, while the characterization of root extract through X-ray diffraction (XRD and element analysis. The morphological feature of the C. forskohlii extract showed a flake like structure and the XRD showed sulfur trioxide (SO 3 and trimer of sulfur trioxide (S 3 O 9 . Through element analysis, elements such as carbon, oxygen, magnesium, aluminum, silicon, phosphorous, and sulfur were identified. Carbon showed the highest weight of 75.49% in comparison to all other elements.

  10. Investigation of surface charge density on solid-liquid interfaces by modulating the electrical double layer.

    Moon, Jong Kyun; Song, Myung Won; Pak, Hyuk Kyu


    A solid surface in contact with water or aqueous solution usually carries specific electric charges. These surface charges attract counter ions from the liquid side. Since the geometry of opposite charge distribution parallel to the solid-liquid interface is similar to that of a capacitor, it is called an electrical double layer capacitor (EDLC). Therefore, there is an electrical potential difference across an EDLC in equilibrium. When a liquid bridge is formed between two conducting plates, the system behaves as two serially connected EDLCs. In this work, we propose a new method for investigating the surface charge density on solid-liquid interfaces. By mechanically modulating the electrical double layers and simultaneously applying a dc bias voltage across the plates, an ac electric current can be generated. By measuring the voltage drop across a load resistor as a function of bias voltage, we can study the surface charge density on solid-liquid interfaces. Our experimental results agree very well with the simple equivalent electrical circuit model proposed here. Furthermore, using this method, one can determine the polarity of the adsorbed state on the solid surface depending on the material used. We expect this method to aid in the study of electrical phenomena on solid-liquid interfaces.

  11. Heat Transfer Characteristics in an Asymmetrical Solid-Liquid System by Molecular Dynamics Simulations

    Feng, Yuan; Liang, Xingang


    Solid-liquid systems widely exist in micro- and nanodevices, and it is necessary to study the heat transfer mechanism through solid-liquid interfaces. An asymmetrical sandwich structure of a solid-liquid system consisting of liquid argon and artificial solid walls that have the same FCC structure with argon but a different atomic masses is composed. Heat transfer characteristics are investigated by the molecular dynamics method. The interaction strength between a liquid and solid plays an essential role in heat transport at solid-liquid interfaces, and the thermal resistance length is inversely proportional to it. The mass arrangement of artificial solid walls also has a significant effect on heat transport as well. A maximum heat flux comes up due to the mismatch in phonon spectra with the increasing atomic mass of one solid wall. The asymmetrical liquid density profiles are obtained with various mass differences between solid walls. Especially, a thermal rectification effect is observed and the magnitude is inextricably bound up with asymmetry.

  12. Influence of dielectric properties on van der Waals/Casimir forces in solid-liquid systems

    van Zwol, P. J.; Palasantzas, G.; De Hosson, J. Th. M.

    In this paper, we present calculations of van der Waals/Casimir forces, described by Lifshitz theory, for the solid-liquid-solid system using measured dielectric functions of all involved materials for the wavelength range from millimeters down to subnanometers. It is shown that even if the

  13. Bionic optical imaging system with aspheric solid-liquid mixed variable-focus lens

    Du, Jia-Wei; Wang, Xuan-Yin; Liang, Dan


    A bionic optical imaging system with an aspheric solid-liquid mixed variable-focus lens was designed and fabricated. The entire system mainly consisted of a doublet lens, a solid-liquid mixed variable-focus lens, a connecting part, and a CCD imaging device. To mimic the structure of the crystalline lens, the solid-liquid mixed variable-focus lens consisted of a polydimethylsiloxane (PDMS) lens, a polymethyl methacrylate lens, and the liquid of ethyl silicone oil. By pumping liquid in or out of the cavity using a microinjector, the curvatures of the front and rear surfaces of the PDMS lens were varied, resulting in a change of focal length. The overall structure of the system was presented, as well as a detailed description of the solid-liquid mixed variable-focus lens, material, and fabrication process. Under different injection volumes, the deformation of the PDMS lens was measured and simulated, pictures were captured, and the optical performance was analyzed in simulations and experiments. The focal length of the system ranged from 25.05 to 14.61 mm, and the variation of the diopter was 28.5D, which was larger than that of the human eye.

  14. Binary Solid-Liquid Phase Diagram of Phenol and t-Butanol: An Undergraduate Physical Chemistry Experiment

    Xu, Xinhua; Wang, Xiaogang; Wu, Meifen


    The determination of the solid-liquid phase diagram of a binary system is always used as an experiment in the undergraduate physical chemistry laboratory courses. However, most phase diagrams investigated in the lab are simple eutectic ones, despite the fact that complex binary solid-liquid phase diagrams are more common. In this article, the…

  15. Binary Solid-Liquid Phase Diagram of Phenol and t-Butanol: An Undergraduate Physical Chemistry Experiment

    Xu, Xinhua; Wang, Xiaogang; Wu, Meifen


    The determination of the solid-liquid phase diagram of a binary system is always used as an experiment in the undergraduate physical chemistry laboratory courses. However, most phase diagrams investigated in the lab are simple eutectic ones, despite the fact that complex binary solid-liquid phase diagrams are more common. In this article, the…

  16. Selective extraction of actinides by calixarenes: application to bioassay analysis; Extraction selective des actinides par les calixarenes: application a l'analyse radiotoxicologique

    Boulet, B


    In the context of nuclear workers monitoring, the aim of this PhD was to selectively isolate U, Pu, and Am from urine to propose a new analytical procedure to the Medical and Biology Analysis Laboratories. The 1,3,5-OCH{sub 3}-2,4,6-OCH{sub 2}CONHOH-p-tert-butyl-calix[6]arene molecule has been selected as a promising extractant for U, Pu, and Am. Its physico-chemical properties and its affinity for UO{sub 2}{sup 2+} have been studied through two approaches, one theoretical (molecular modelling at DFT level), and one experimental. The extractions of the three actinides by the hydroxamic calix[6]arene were quantitative in liquid-liquid and solid-liquid systems. Their separation has also been shown possible and efficient. After optimization, the proposed procedure should allow the laboratories to carry out the chemical treatment of urine, before the measurement, in one day instead of the three days needed nowadays. (author)

  17. Development and Optimization of a Flocculation Procedure for Improved Solid-Liquid Separation of Digested Biomass

    Patton, Caroline; Lischeske, James J.; Sievers, David A.


    One viable treatment method for conversion of lignocellulosic biomass to biofuels begins with saccharification (thermochemical pretreatment and enzymatic hydrolysis), followed by fermentation or catalytic upgrading to fuels such as ethanol, butanol, or other hydrocarbons. The post-hydrolysis slurry is typically 4-8 percent insoluble solids, predominantly consisting of lignin. Suspended solids are known to inhibit fermentation as well as poison catalysts and obstruct flow in catalyst beds. Thus a solid-liquid separation following enzymatic hydrolysis would be highly favorable for process economics, however the material is not easily separated by filtration or gravimetric methods. Use of a polyacrylamide flocculant to bind the suspended particles in a corn stover hydrolyzate slurry into larger flocs (1-2mm diameter) has been found to be extremely helpful in improving separation. Recent and ongoing research on novel pretreatment methods yields hydrolyzate material with diverse characteristics. Therefore, we need a thorough understanding of rapid and successful flocculation design in order to quickly achieve process design goals. In this study potential indicators of flocculation performance were investigated in order to develop a rapid analysis method for flocculation procedure in the context of a novel hydrolyzate material. Flocculation conditions were optimized on flocculant type and loading, pH, and mixing time. Filtration flux of the hydrolyzate slurry was improved 170-fold using a cationic polyacrylamide flocculant with a dosing of approximately 22 mg flocculant/g insoluble solids at an approximate pH of 3. With cake washing, sugar recovery exceeded 90 percent with asymptotic yield at 15 L wash water/kg insoluble solids.

  18. Accelerated Metastable Solid-liquid Interdiffusion Bonding with High Thermal Stability and Power Handling

    Huang, Ting-Chia; Smet, Vanessa; Kawamoto, Satomi; Pulugurtha, Markondeya R.; Tummala, Rao R.


    Emerging high-performance systems are driving the need for advanced packaging solutions such as 3-D integrated circuits (ICs) and 2.5-D system integration with increasing performance and reliability requirements for off-chip interconnections. Solid-liquid interdiffusion (SLID) bonding resulting in all-intermetallic joints has been proposed to extend the applicability of solders, but faces fundamental and manufacturing challenges hindering its wide adoption. This paper introduces a Cu-Sn SLID interconnection technology, aiming at stabilization of the microstructure in the Cu6Sn5 metastable phase rather than the usual stable Cu3Sn phase. This enables formation of a void-free interface yielding higher mechanical strength than standard SLID bonding, as well as significantly reducing the transition time. The metastable SLID technology retains the benefits of standard SLID with superior I/O pitch scalability, thermal stability and current handling capability, while advancing assembly manufacturability. In the proposed concept, the interfacial reaction is controlled by introducing Ni(P) diffusion barrier layers, designed to effectively isolate the metastable Cu6Sn5 phase preventing any further transformation. Theoretical diffusion and kinetic models were applied to design the Ni-Cu-Sn interconnection stack to achieve the targeted joint composition. A daisy chain test vehicle was used to demonstrate this technology as a first proof of concept. Full transition to Cu6Sn5 was successfully achieved within a minute at 260°C as confirmed by scanning electron microscope (SEM) and x-ray energy dispersive spectroscopy (XEDS) analysis. The joint composition was stable through 10× reflow, with outstanding bond strength averaging 90 MPa. The metastable SLID interconnections also showed excellent electromigration performance, surviving 500 h of current stressing at 105 A/cm2 at 150°C.

  19. Atomistic simulation of solid-liquid coexistence for molecular systems: application to triazole and benzene.

    Eike, David M; Maginn, Edward J


    A method recently developed to rigorously determine solid-liquid equilibrium using a free-energy-based analysis has been extended to analyze multiatom molecular systems. This method is based on using a pseudosupercritical transformation path to reversibly transform between solid and liquid phases. Integration along this path yields the free energy difference at a single state point, which can then be used to determine the free energy difference as a function of temperature and therefore locate the coexistence temperature at a fixed pressure. The primary extension reported here is the introduction of an external potential field capable of inducing center of mass order along with secondary orientational order for molecules. The method is used to calculate the melting point of 1-H-1,2,4-triazole and benzene. Despite the fact that the triazole model gives accurate bulk densities for the liquid and crystal phases, it is found to do a poor job of reproducing the experimental crystal structure and heat of fusion. Consequently, it yields a melting point that is 100 K lower than the experimental value. On the other hand, the benzene model has been parametrized extensively to match a wide range of properties and yields a melting point that is only 20 K lower than the experimental value. Previous work in which a simple "direct heating" method was used actually found that the melting point of the benzene model was 50 K higher than the experimental value. This demonstrates the importance of using proper free energy methods to compute phase behavior. It also shows that the melting point is a very sensitive measure of force field quality that should be considered in parametrization efforts. The method described here provides a relatively simple approach for computing melting points of molecular systems.

  20. Simultaneous Microwave Extraction and Separation of Volatile and Non-Volatile Organic Compounds of Boldo Leaves. From Lab to Industrial Scale

    Loïc Petigny


    Full Text Available Microwave extraction and separation has been used to increase the concentration of the extract compared to the conventional method with the same solid/liquid ratio, reducing extraction time and separate at the same time Volatile Organic Compounds (VOC from non-Volatile Organic Compounds (NVOC of boldo leaves. As preliminary study, a response surface method has been used to optimize the extraction of soluble material and the separation of VOC from the plant in laboratory scale. The results from the statistical analysis revealed that the optimized conditions were: microwave power 200 W, extraction time 56 min and solid liquid ratio of 7.5% of plants in water. Lab scale optimized microwave method is compared to conventional distillation, and requires a power/mass ratio of 0.4 W/g of water engaged. This power/mass ratio is kept in order to upscale from lab to pilot plant.

  1. Solid-liquid phase diagram of disubstituted benzene systems

    黑恩成; 刘国杰


    The cooling curves of different compositions of the systems of ortho-chlorotoluene/para-chlorotoluene and ortho-nitrochlorobenzene/para-nitrochlorobenzene are carefully determined by the thermal analysis method. The crystals obtained are also tested. The conclusion that both systems are of simple eutectic diagram but not the solid solution diagram with a minimum melting point is confirmed. The characteristics of the diagram are explained according to the physical and thermodynarmc properties of the components.

  2. Thermodynamic Investigation of the Effect of Interface Curvature on the Solid-Liquid Equilibrium and Eutectic Point of Binary Mixtures.

    Liu, Fanghui; Zargarzadeh, Leila; Chung, Hyun-Joong; Elliott, Janet A W


    Thermodynamic phase behavior is affected by curved interfaces in micro- and nanoscale systems. For example, capillary freezing point depression is associated with the pressure difference between the solid and liquid phases caused by interface curvature. In this study, the thermal, mechanical, and chemical equilibrium conditions are derived for binary solid-liquid equilibrium with a curved solid-liquid interface due to confinement in a capillary. This derivation shows the equivalence of the most general forms of the Gibbs-Thomson and Ostwald-Freundlich equations. As an example, the effect of curvature on solid-liquid equilibrium is explained quantitatively for the water/glycerol system. Considering the effect of a curved solid-liquid interface, a complete solid-liquid phase diagram is developed over a range of concentrations for the water/glycerol system (including the freezing of pure water or precipitation of pure glycerol depending on the concentration of the solution). This phase diagram is compared with the traditional phase diagram in which the assumption of a flat solid-liquid interface is made. We show the extent to which nanoscale interface curvature can affect the composition-dependent freezing and precipitating processes, as well as the change in the eutectic point temperature and concentration with interface curvature. Understanding the effect of curvature on solid-liquid equilibrium in nanoscale capillaries has applications in the food industry, soil science, cryobiology, nanoporous materials, and various nanoscience fields.

  3. Detection of Exposure to Environmental Pesticides During Pregnancy by the Analysis of Maternal Hair Using GC–MS

    Posecion, N.; Ostrea, E.; Bielawski, D.; Corrion, M.; Seagraves, J.; Jin, Y.


    Several classes of pesticides were extracted from maternal hair by solid-liquid extraction. Analysis of their selected metabolites involved a methanolic/hydrochloric acid methyl ester derivatization and liquid–liquid extraction. Gas chromatography electron impact mass spectrometry was used to detect and quantify the pesticides and metabolites. Recovery of parent compounds and metabolites from the analysis of spiked hair ranged from 87 to 112% with coefficients of variation less than 11%. Limi...

  4. Nano scale dynamics of bubble nucleation in confined liquid subjected to rapid cooling: Effect of solid-liquid interfacial wettability

    Hasan, Mohammad Nasim; Rabbi, Kazi Fazle; Mukut, K. M.; Tamim, Saiful Islam; Faisal, A. H. M.


    This study focuses on the occurrence of bubble nucleation in a liquid confined in a nano scale confinement and subjected to rapid cooling at one of its wall. Due to the very small size scale of the present problem, we adopt the molecular dynamics (MD) approach. The liquid (Argon) is confined within two solid (Platinum) walls. The temperature of the upper wall of the confinement is maintained at 90 K while the lower wall is being cooled rapidly to 50 K from initial equilibrium temperature of 90 K within 0.1 ns. This results in the nucleation and formation of nanobubbles in the liquid. The pattern of bubble nucleation has been studied for three different conditions of solid-liquid interfacial wettability such as hydrophilic, hydrophobic and neutral. Behavior of bubble nucleation is significantly different in the three case of solid-liquid interfacial wettability. In case of the hydrophobic confinement (weakly adsorbing), the liquid cannot achieve deeper metastability; vapor layers appear immediately on the walls. In case of the neutral confinement (moderately adsorbing), bubble nucleation is promoted by the walls where the nucleation is heterogeneous. In case of the hydrophilic walls (strongly adsorbing) bubbles are developed inside the liquid; that is the nucleation process is homogeneous. The variation in bubble nucleation under different conditions of surface wettability has been studied by the analysis of number density distribution, spatial temperature distribution, spatial number density distribution and heat flux through the upper and lower walls of the confinement. The present study indicates that the variation of heat transfer efficiency due to different surface wettability has significant effect on the size, shape and location of bubble nucleation in case rapid cooling of liquid in nano confinement.

  5. Numerical formulation of composition segregation at curved solid-liquid interface during steady state solidification process

    Wang, Jai-Ching


    The lateral solute segregation that results from a curved solid-liquid interface shape during steady state unidirectional solidification of a binary alloy system has been studied both analytically and numerically by Coriell, Bosivert, Rehm, and Sekerka. The system under their study is a two dimensional rectangular system. However, most real growth systems are cylindrical systems. Thus, in a previous study, we have followed Coriell etc. formalism and obtained analytical results for lateral solute segregation for an azimuthal symmetric cylindrical binary melt system during steady state solidification process. The solid-liquid interface shape is expressed as a series combination of Bessel functions. In this study a computer program has been developed to simulate the lateral solute segregation.

  6. Effect of thermal convection on the shape of a solid-liquid interface

    Mennetrier, C.; Chopra, M. A.; De Groh, H. C., III


    The effect of thermal convection on the shape of solid-liquid interface was investigated in experiments conducted in a transparent Bridgman-type directional solidification furnace. The relationship was numerically modeled using a standard 2D finite-difference approach, with the solid-liquid deformable interface approximated by a blocking-off technique. The directional solidification furnace was used with pure succinonitrile (which is also transparent) contained in a long square ampoule made of borosilicate glass. With the furnace in the vertical configuration, a flat interface was observed, in agreement with the model. On the other hand, a highly distorted interface was obtained in the horizontal configuration; the numerical results showed a strong recirculating cell in front of the interface due to natural thermal convection. The results indicate that thermal convection is responsible for the interface distortion.

  7. In situ transmission electron microscopy of solid-liquid phase transition of silica encapsulated bismuth nanoparticles

    Hu, Jianjun; Hong, Yan; Muratore, Chris; Su, Ming; Voevodin, Andrey A.


    The solid-liquid phase transition of silica encapsulated bismuth nanoparticles was studied by in situ transmission electron microscopy (TEM). The nanoparticles were prepared by a two-step chemical synthesis process involving thermal decomposition of organometallic precursors for nucleating bismuth and a sol-gel process for growing silica. The microstructural and chemical analyses of the nanoparticles were performed using high-resolution TEM, Z-contrast imaging, focused ion beam milling, and X-ray energy dispersive spectroscopy. Solid-liquid-solid phase transitions of the nanoparticles were directly recorded by electron diffractions and TEM images. The silica encapsulation of the nanoparticles prevented agglomeration and allowed particles to preserve their original volume upon melting, which is desirable for applications of phase change nanoparticles with consistently repeatable thermal properties.

  8. Solid-Liquid equilibrium of n-alkanes using the Chain Delta Lattice Parameter model

    Coutinho, João A.P.; Andersen, Simon Ivar; Stenby, Erling Halfdan


    The formation of a solid phase in liquid mixtures with large paraffinic molecules is a phenomenon of interest in the petroleum, pharmaceutical, and biotechnological industries among onters. Efforts to model the solid-liquid equilibrium in these systems have been mainly empirical and with different...... degrees of success.An attempt to describe the equilibrium between the high temperature form of a paraffinic solid solution, commonly known as rotator phase, and the liquid phase is performed. The Chain Delta Lattice Parameter model (CDLP) is developed allowing a successful description of the solid-liquid...... equilibrium of n-alkanes ranging from n-C_20 to n-C_40.The model is further modified to achieve a more correct temperature dependence because it severely underestimates the excess enthalpy. It is shown that the ratio of excess enthalpy and entropy for n-alkane solid solutions, as happens for other solid...

  9. Engineering evaluation of solids/liquids separation processes applicable to sludge treatment project

    Duncan, J.B.


    This engineering study looks at the solids/liquids separation unit operations after the acid dissolution of the K Basin sludge treatment. Unit operations considered were centrifugation, filtration (cartridge, cross flow, and high shear filtration) and gravity settling. The recommended unit operations for the solids/liquids separations are based upon the efficiency, complexity, and off-the-shelf availability and adaptability. The unit operations recommended were a Robatel DPC 900 centrifuge followed by a nuclearized 31WM cartridge filter. The Robatel DPC 900 has been successfully employed in the nuclear industry on a world wide scale. The 31WM cartridge filter has been employed for filtration campaigns in both the government and civilian nuclear arenas.

  10. Empirical approach to solid-liquid mass transfer in a three-phase sparged reactor

    Gogoi, N.C.; Dutta, N.N. [Regional Research Laboratory, Jodrhat (India). Chemical Engineering Division


    Solid-liquid mass transfer coefficients were determined in three-phase sparged reactors (TPSRs) using benzoic acid dissolution. Experiments were performed in three acrylic column reactors of internal diameter 0.1, 0.2 and 0.3 m respectively. The superficial gas velocities were varied up to 0.35 m s{sup -1}. Using experimental data generated in this work and data reported in the literature for a 0.4-m diameter reactor, the effect of the reactor diameter on the solid-liquid mass transfer coefficient, k{sub SL}, was investigated. It is demonstrated that an empirical approach can be used to determine k{sub SL} from an appropriate mass transfer correlation useful for the design of TPSRs. 20 refs., 5 figs., 3 tabs.

  11. Bioproduction of benzaldehyde in a solid-liquid two-phase partitioning bioreactor using Pichia pastoris.

    Jain, Ashu N; Khan, Tanya R; Daugulis, Andrew J


    The bioproduction of benzaldehyde from benzyl alcohol using Pichia pastoris was examined in a solid-liquid two-phase partitioning bioreactor (TPPB) to reduce substrate and product inhibition. Rational polymer selection identified Elvax 40W as an effective sequestering phase, possessing partition coefficients for benzyl alcohol and benzaldehyde of 3.5 and 35.4, respectively. The use of Elvax 40W increased the overall mass of benzaldehyde produced by approx. 300% in a 5 l bioreactor, relative to a single phase biotransformation. The two-phase system had a molar yield of 0.99, indicating that only minor losses occurred. These results provide a promising starting point for solid-liquid TPPBs to enhance benzaldehyde production, and suggest that multiple, targeted polymers may provide relief for transformations characterized by multiple inhibitory substrates/product/by-products.

  12. Interaction of Porosity with an Advancing Solid/Liquid Interface: a Real-Time Investigation

    Sen, S.; Kaukler, W.; Catalina, A.; Stefanescu, D.; Curreri, P.


    Problems associated with formation of porosity during solidification continue to have a daily impact on the metal forming industry. Several past investigations have dealt with the nucleation and growth aspects of porosity. However, investigations related to the interaction of porosity with that of a solidification front has been limited mostly to organic analogues. In this paper we report on real time experimental observations of such interactions in metal alloys. Using a state of the art X-Ray Transmission Microscope (XTM) we have been able to observe and record the dynamics of the interaction. This includes distortion of the solid/liquid interface near a poro.sity, solute segr,egation patterns surrounding a porosity and the change in shape of the porosity during interaction with an advancing solid/liquid interface. Results will be presented for different Al alloys and growth conditions. The experimental data will be compared to theory using a recently developed 2D numerical model. The model employs a finite difference approach where the solid/liquid interface is defined through the points at which the interface intersects the grid lines. The transport variables are calculated at these points and the motion of the solidification front is determined by the magnitude of the transport variables. The model accounts for the interplay of the thermal and solutal field and the influence of capilarity to predict the shape of the solid/liquid interface with time in the vicinity of porosity. One can further calculate the perturbation of the solutal field by the presence of porosity in the melt.

  13. A Spectrometric Setup for Synchronous Total Internal Reflection Fluorescence Measurement at the Solid/Liquid Interface


    A spectrometric setup to perform total internal reflection fluorescence (TIRF) and synchronous TIRF measurements at solid/liquid interfaces is presented. The combination of TIRF and synchronous fluorescence was proposed to analyze simultaneously different components at interfaces. The TIRF excitation, emission and synchronous spectra of a water-soluble porphyrin were obtained from water/glass interface using this setup without the existence of a surfactant.

  14. Interaction of Porosity with an Advancing Solid/Liquid Interface: a Real-Time Investigation

    Sen, S.; Kaukler, W.; Catalina, A.; Stefanescu, D.; Curreri, P.


    Problems associated with formation of porosity during solidification continue to have a daily impact on the metal forming industry. Several past investigations have dealt with the nucleation and growth aspects of porosity. However, investigations related to the interaction of porosity with that of a solidification front has been limited mostly to organic analogues. In this paper we report on real time experimental observations of such interactions in metal alloys. Using a state of the art X-Ray Transmission Microscope (XTM) we have been able to observe and record the dynamics of the interaction. This includes distortion of the solid/liquid interface near a poro.sity, solute segr,egation patterns surrounding a porosity and the change in shape of the porosity during interaction with an advancing solid/liquid interface. Results will be presented for different Al alloys and growth conditions. The experimental data will be compared to theory using a recently developed 2D numerical model. The model employs a finite difference approach where the solid/liquid interface is defined through the points at which the interface intersects the grid lines. The transport variables are calculated at these points and the motion of the solidification front is determined by the magnitude of the transport variables. The model accounts for the interplay of the thermal and solutal field and the influence of capilarity to predict the shape of the solid/liquid interface with time in the vicinity of porosity. One can further calculate the perturbation of the solutal field by the presence of porosity in the melt.

  15. The 2D Alternative Binary L-J System: Solid-Liquid Phase Diagram

    ZHANG Zhi; CHEN Li-Rong


    The Lennard-Jones potential is introduced into the Collins model and is generalized to the two-dimensionalalternative binary system. The Gibbs free energy of the binary system is calculated. According to the thermodynamicconditions of solid-liquid equilibrium, the "cigar-type" phase diagram and the phase diagram with a minimum areobtained. The results are quite analogous to the behavior of three-dimensional substances.

  16. Determination of the Solid-Liquid Interface Energy in the Al-Cu-Ag System

    Bulla, A.; Carreno-Bodensiek, C.; Pustal, B.; Berger, R.; Bührig-Polaczek, A.; Ludwig, A.


    The solid-liquid interface energy, σ SL , is of major importance during phase transformation. It has a strong influence on solidification morphologies and the final grain structure. The “grain boundary groove in an applied temperature gradient” method developed by Gündüz et al.[6] was found to be suitable for measuring the solid-liquid interface energy in ternary alloy systems (e.g., Al-Cu-Ag). In order to measure the solid-liquid interface energy, a radial heat flow apparatus was constructed and assembled. This apparatus ensures a stable temperature gradient for hours and leads to grain boundary grooves in chemical equilibrium. After rapid quenching, the samples were metallographically prepared and the local curvature of the grooves was analyzed. To determine the interface energy, the Gibbs Thomson equation was used, which requires the local curvature of the grain boundary grooves and the adherent local undercooling obtained from heat flux simulations on the scale of the grooves.

  17. Mixed Model for Silt-Laden Solid-Liquid Two-Phase Flows

    唐学林; 徐宇; 吴玉林


    The kinetic theory of molecular gases was used to derive the governing equations for dense solid-liquid two-phase flows from a microscopic flow characteristics viewpoint by multiplying the Boltzmann equation for each phase by property parameters and integrating over the velocity space. The particle collision term was derived from microscopic terms by comparison with dilute two-phase flow but with consideration of the collisions between particles for dense two-phase flow conditions and by assuming that the particle-phase velocity distribution obeys the Maxwell equations. Appropriate terms from the dilute two-phase governing equations were combined with the dense particle collision term to develop the governing equations for dense solid-liquid turbulent flows. The SIMPLEC algorithm and a staggered grid system were used to solve the discretized two-phase governing equations with a Reynolds averaged turbulence model. Dense solid-liquid turbulent two-phase flows were simulated for flow in a duct. The simulation results agree well with experimental data.

  18. Ultrasound-assisted extraction of pectin from sisal waste.

    Maran, J Prakash; Priya, B


    In this study, an efficient ultrasound-assisted extraction (UAE) of pectin from sisal waste was investigated and optimized. Response surface methodology (RSM) based on a three-level four-factor Box-Behnken response surface design (BBD) was employed to optimize the extraction conditions (ultrasonic power, extraction temperature, extraction time and solid-liquid ratio). Analysis of variance showed that the contribution of a quadratic model was significant for the pectin extraction yield. The experimental yield (29.32%) was obtained under the optimal condition (ultrasonic power of 61 W, temperature of 50°C, time of 26 min and SL ratio of 1:28 g/ml) was well agreement with predicted values. Therefore, ultrasound-assisted extraction could be used as an alternative method to extract pectin from sisal waste with the advantages of lower extraction temperatures, shorter extraction time and reduced energy consumption. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Influence of ripening stages of tomatoes in the analysis of pesticides by gas chromatography

    Sousa,Flaviane A. de; Neves,Antônio A.; Maria Eliana L. R. Queiroz; Heleno,Fernanda F.; Teófilo, Reinaldo F.; Pinho,Gevany P.


    Some parameters of tomato fruits ripening such as color, pH, ºBrix, acidity and lycopene and β-carotene content were evaluated during the ripening of fruits. Five pesticides were quantified in organic extracts derived from tomatoes at different stages of maturation. The solid-liquid extraction technique with partition at low temperature (SLE-PLT) was used to obtain these organic extracts. The matrix effect of tomato was calculated from the results of analysis by gas chromatography with e...

  20. Orientation dependence of heterogeneous nucleation at the Cu-Pb solid-liquid interface

    Palafox-Hernandez, J. Pablo; Laird, Brian B.


    In this work, we examine the effect of surface structure on the heterogeneous nucleation of Pb crystals from the melt at a Cu substrate using molecular-dynamics (MD) simulation. In a previous work [Palafox-Hernandez et al., Acta Mater. 59, 3137 (2011)] studying the Cu/Pb solid-liquid interface with MD simulation, we observed that the structure of the Cu(111) and Cu(100) interfaces was significantly different at 625 K, just above the Pb melting temperature (618 K for the model). The Cu(100) interface exhibited significant surface alloying in the crystal plane in contact with the melt. In contrast, no surface alloying was seen at the Cu(111) interface; however, a prefreezing layer of crystalline Pb, 2-3 atomic planes thick and slightly compressed relative to bulk Pb crystal, was observed to form at the interface. We observe that at the Cu(111) interface the prefreezing layer is no longer present at 750 K, but surface alloying in the Cu(100) interface persists. In a series of undercooling MD simulations, heterogeneous nucleation of fcc Pb is observed at the Cu(111) interface within the simulation time (5 ns) at 592 K—a 26 K undercooling. Nucleation and growth at Cu(111) proceeded layerwise with a nearly planar critical nucleus. Quantitative analysis yielded heterogeneous nucleation barriers that are more than two orders of magnitude smaller than the predicted homogeneous nucleation barriers from classical nucleation theory. Nucleation was considerably more difficult on the Cu(100) surface-alloyed substrate. An undercooling of approximately 170 K was necessary to observe nucleation at this interface within the simulation time. From qualitative observation, the critical nucleus showed a contact angle with the Cu(100) surface of over 90°, indicating poor wetting of the Cu(100) surface by the nucleating phase, which according to classical heterogeneous nucleation theory provides an explanation of the large undercooling necessary to nucleate on the Cu(100) surface

  1. Dry-Surface Simulation Method for the Determination of the Work of Adhesion of Solid-Liquid Interfaces.

    Leroy, Frédéric; Müller-Plathe, Florian


    We introduce a methodology, referred to as the dry-surface method, to calculate the work of adhesion of heterogeneous solid-liquid interfaces by molecular simulation. This method employs a straightforward thermodynamic integration approach to calculate the work of adhesion as the reversible work to turn off the attractive part of the actual solid-liquid interaction potential. It is formulated in such a way that it may be used either to evaluate the ability of force fields to reproduce reference values of the work of adhesion or to optimize force-field parameters with reference values of the work of adhesion as target quantities. The methodology is tested in the case of water on a generic model of nonpolar substrates with the structure of gold. It is validated through a quantitative comparison to phantom-wall calculations and against a previous characterization of the thermodynamics of the gold-water interface. It is found that the work of adhesion of water on nonpolar substrates is a nonlinear function of the microscopic solid-liquid interaction energy parameter. We also comment on the ability of mean-field approaches to predict the work of adhesion of water on nonpolar substrates. In addition, we discuss in detail the information on the solid-liquid interfacial thermodynamics delivered by the phantom-wall approach. We show that phantom-wall calculations yield the solid-liquid interfacial tension relative to the solid surface tension rather than the absolute solid-liquid interfacial tension as previously believed.

  2. Dynamic versus static ultrasonic sample treatment for the solid-liquid pre-concentration of mercury from human urine.

    Patricio, A; Fernandez, C; Mota, A M; Capelo, J L


    Dynamic and static ultrasonic procedures involving ultrasonic bath and tandem focused ultrasound (i.e. two probes were used in the same sample treatment) have been assessed in order to implement a reliable solid-liquid back extraction of mercury from commercial resins (dowex and chelex-100), previously used to concentrate Hg(II) from treated urine. The urine had been previously treated with an advanced oxidation process provided by the conjunction of potassium permanganate, hydrochloric acid and high intensity focused ultrasound, which allowed that organic matter degradation was achieved in less than 3min. 95+/-10% of mercury in the certified urine and 97+/-6% of the spiked methyl-mercury was recovered with the dowex resin plus the static ultrasonic procedure, whilst 96+/-11% of the spiked mercury was recovered with the dowex resin plus the dynamic procedure, for which ultrasonication was not necessary. The Hg pre-concentration factor used in this work was 8 (20mL of urine to 2.5mL of acid), but different volume ratios can be used in order to increase this factor.

  3. High resolution of racemic phenylalanine with dication imidazolium-based chiral ionic liquids in a solid-liquid two-phase system.

    Huang, Xiaoxia; Wu, Haoran; Wang, Zhixia; Luo, Yingjie; Song, Hang


    A novel solid-liquid two-phase system was developed for the chiral separation of racemic phenylalanine with new dication imidazolium-based chiral ionic liquids. Preliminary experiments showed distinct enantioselectivity in amino acid extraction with the novel solid-liquid two-phase system, more L-enantiomer of amino acid cooperatively interacted with ionic liquids and copper ions to be the solid phase. Various factors, including the alkyl chain length of cations of ionic liquids, the amount of copper acetate, the ratio of n(ILs)/n(Cu(2+)), the amount of water and racemic phenylalanine, the resolution time together with the resolution temperature, were systematically investigated for their influence on resolution efficiency. The results showed that, under a certain condition, the enantiomeric excess value and the yield of phenylalanine in liquid phase (mainly containing D-enantiomer) were 67.8% and 96.5%, the enantiomeric excess value and the yield of phenylalanine in solid phase (mainly containing L-enantiomer) were 99.2% and 85.2%. Finally, 2D NMR technology, infrared spectroscopy and molecular simulation method were used to study the interaction mechanism. The results indicated that L-enantiomer of phenylalanine interacts more strongly with chiral ILs and Cu(2+). The novel system has characteristics of free-organic solvent, simple operation, fast separation process and very high resolution efficiency for racemic phenylalanine. This work could provide a new and alternative resolution approach for other chiral separations.

  4. 麒麟菜中多糖的提取研究%Study on Extraction of Polysaccharides from Eucheuma

    杜云建; 赵玉巧; 黄国军


    Hot water extraction of polysaccharides from Eucheuma was studied. The effects of extraction time, extraction temperature, extraction solid-liquid ratio on extraction rate were investigated by single factor experiments. The optimal extraction conditions with single factors were as follows: solid-liquid ratio 1 : 90, extracting time 3 h, extraction temperature 100 ℃. The extraction conditions were optimized by response surface analysis, and the optimized extraction conditions ware as follows: solid-liquid ratio 1 : 95, extracting time 3.7 h, extraction temperature 97.3 ℃, the extraction rate was 31.53%. The optimized extraction conditions were verificated through the experiments; results show the correctness of the model.%采用热水浸提法提取麒麟菜中的多糖。研究了提取温度、提取时间以及固液比对多糖提取率的影响,单因素试验结果表明较佳的提取条件为,时间为3h,提取温度为100℃,提取液固比为90:1,通过响应面优化得到提取的最佳工艺条件为:时间为3.7h,温度为97.3℃,液固比为95:1,提取率为31.5261%,并通过试验对其进行验证,结果证明了所建模型的正确性。

  5. Numerical Calculation of the Morphology of a Solid/Liquid Interface Near an Insoluble Particle

    Catalina, Adrian V.; Stefanescu, Doru M.; Sen, Subhayu


    A numerical mathematical model capable of accurately describing the evolution of the shape of the solid/liquid interface in the proximity of a foreign particle is presented in this paper. The model accounts for the influence of the temperature gradient and the Gibbs-Thomson and disjoining pressure effects. It shows that for the systems characterized by k(sub P) interface curvature to change its sign in the close-contact particle/interface region. It also shows that the increase of the temperature gradient diminishes the effect of the disjoining pressure. Calculated critical solidification velocities for the pushing/engulfment transition are compared with experimental measurements performed in microgravity conditions.

  6. Determination of the mean solid-liquid interface energy of pivalic acid

    Singh, N. B.; Gliksman, M. E.


    A high-confidence solid-liquid interfacial energy is determined for an anisotropic material. A coaxial composite having a cylindrical specimen chamber geometry provides a thermal gradient with an axial heating wire. The surface energy is derived from measurements of grain boundary groove shapes. Applying this method to pivalic acid, a surface energy of 2.84 erg/sq cm was determined with a total systematic and random error less than 10 percent. The value of interfacial energy corresponds to 24 percent of the latent heat of fusion per molecule.

  7. Prediction of Solid-Liquid Interface Stability by Coupling M-S Model with CALPHAD Method

    Ruijie ZHANG; Zhi HE; Zhongwei CHEN; Wanqi JIE


    A method to predict the solid-liquid interface stability during unidirectional solidification is developed by coupling M-S model with CALPHAD method. The method was applied to Al-0.38 Zn and Al-0.34 Si-0.14 Mg (wt pct) alloys, and the predicted results were compared with some former experimental data of the two alloys. The good agreement between the calculation results and the experimental data demonstrates the superiority of the present method to the classical one based on constant parameter assumptions.

  8. Impact of sludge properties on solid-liquid separation of activated sludge

    Christensen, Morten Lykkegaard


    and dissolved extracellular polymeric substances (EPS). Polyvalent ions improve the floc strangth and improve the separation whereas monovalent ions (e.g. from road salt, sea water intrusion and industry) reduces impair the separation. Further high pH impairs the separation process due to floc disintegration......Solid-liquid separation of activated sludge is important both directly after the biological treatment of wastewater and for sludge dewatering. The separation of solid from the treated wastewater can be done by clarifiers (conventional plants) or membrane (MBR). Further, part of the sludge is taken...

  9. Application of a Numerical Model of Solid-Liquid Hammer in Pipeline Transport

    LiPengcheng; WuBaosheng; ZhouJianjun; HanWenliang


    The water hammer in pipelines for the transportation of plumbum and Zn mining tailing, supplied by centrifugal pumps, was studied by a numerical model of water hammer for pseudo-homogeneous solid-liquid flows. The simulation results were in good agreement with earlier experiments. The simulation result of air tanks installed on pipelines proved that the installation of air tanks is the most effective measure to reduce the water hammer associated with return flow caused by rapid closing of check valves. Other effective measures include the use of longer check-valve closure time or installation of the relief valves on the lower segments of the pipelines.

  10. Mephisto - Research equipment for the study of solid/liquid interface destabilization in metal alloys

    Favier, J. J.; Malmejac, Y.; Praizey, J. P.; Cambon, G.; Barillot, R.; Changeart, F. J.


    Preliminary results of a feasiblity study of space apparatus intended for solid/liquid destabilization in metal alloys, the Mephisto project, are presented. The phenomena that Mephisto will observe, the parameters it will measure, and the scientific studies that it will perform are stated. A general description is given of the instrument, its experimental tubes, and the experiment process. The environmental and thermal constraints, electrical characteristics, and the characteristics of the different signals are outlined. Finally, the requirements of the payload interfaces on which the equipment will be mounted are set forth, including mechanical/geometrical interfaces, thermal interfaces, and electrical interfaces.

  11. The discrete multi-hybrid system for the simulation of solid-liquid flows.

    Alessio Alexiadis

    Full Text Available This study proposes a model based on the combination of Smoothed Particle Hydrodynamics, Coarse Grained Molecular Dynamics and the Discrete Element Method for the simulation of dispersed solid-liquid flows. The model can deal with a large variety of particle types (non-spherical, elastic, breakable, melting, solidifying, swelling, flow conditions (confined, free-surface, microscopic, and scales (from microns to meters. Various examples, ranging from biological fluids to lava flows, are simulated and discussed. In all cases, the model captures the most important features of the flow.

  12. Sliding fluids: Dewetting experiments reveal the solid/liquid boundary condition

    Baeumchen, Oliver; Lessel, Matthias; Fetzer, Renate; Seemann, Ralf; Jacobs, Karin, E-mail: k.jacobs@physik.uni-saarland.d [Department of Experimental Physics, Saarland University, D-66041 Saarbruecken (Germany)


    Nanoscale liquid polymer films are ideal candidates to probe the solid/liquid boundary condition: Prepared on hydrophobized Si wafer, the films are not stable, they dewet. The dewetting induces a flow without applying an external force. Probing the dynamics of the dewetting film and the morphology of the liquid front, we can deduce the slip length. A variation of the type of hydrophobic coating (silane or Teflon (registered)) of the Si wafer enables us to tune the boundary condition from a no-slip to a nearly full-slip condition. For a short introduction to the topic, we offer a phenomenological approach and supply multimedia files.

  13. Effects of ultrahigh pressure extraction on yield and antioxidant activity of chlorogenic acid and cynaroside extracted from flower buds of Lonicera japonica.

    Hu, Wen; Guo, Ting; Jiang, Wen-Jun; Dong, Guang-Li; Chen, Da-Wei; Yang, Shi-Lin; Li, He-Ran


    The present study was designed to establish and optimize a new method for extracting chlorogenic acid and cynaroside from Lonicera japonica Thunb. through orthogonal experimental designl. A new ultrahigh pressure extraction (UPE) technology was applied to extract chlorogenic acid and cynaroside from L. japonica. The influential factors, including solvent type, ethanol concentration, extraction pressure, time, and temperature, and the solid/liquid ratio, have been studied to optimize the extraction process. The optimal conditions for the UPE were developed by quantitative analysis of the extraction products by HPLC-DAD in comparison with standard samples. In addition, the microstructures of the medicinal materials before and after extraction were studied by scanning electron microscopy (SEM). Furthermore, the extraction efficiency of different extraction methods and the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities of the extracts were investigated. The optimal conditions for extracting chlorogenic acid and cynaroside were as follows: ethanol concentration, 60%; extraction pressure, 400 MPa; extraction time, 2 min; extraction temperature, 30 °C; and the solid/liquid ratio, 1 : 50. Under these conditions, the yields of chlorogenic acid and cynaroside were raised to 4.863% and 0.080%, respectively. Compared with other extraction methods, such as heat reflux extraction (HRE), ultrasonic extraction (UE), and Sohxlet extraction (SE), the UPE method showed several advantages, including higher extraction yield, shorter extraction time, lower energy consumption, and higher purity of the extracts. This study could help better utilize L. japonica flower buds as a readily accessible source of natural antioxidants in food and pharmaceutical industries.

  14. Resonance Extraction from the SAID Analysis

    Workman, Ron


    Resonances are extracted from a number of energy-dependent and single-energy fits to scattering data. The influence of recent, precise EPECUR data is investigated. Results for the single-energy fits are derived using the L+P method of analysis and are compared to those obtained using contour integration applied to the global energy-dependent fits.

  15. Synthesis of New Phosphorus-Containing (CoPolyesters Using Solid-Liquid Phase Transfer Catalysis and Product Characterization

    Gheorghe Ilia


    Full Text Available This paper is directed towards the development of safe, and thermally stable solid polymer electrolytes. Linear phosphorus-containing (copolyesters are described, including their synthesis, thermal analysis, conductivity, and non-flammability. Polycondensation of phenylphosphonic dichloride (PPD with poly(ethylene glycol (PEG 12000 with and without bisphenol A (BA was carried out using solid-liquid phase transfer catalysis. Potassium phosphate is used as base. Yields in the range of 85.0–88.0%, and inherent viscosities in the range of 0.32–0.58 dL/g were obtained. The polymers were characterized by gel permeation chromatography, FT-IR, 1H- and 31P-NMR spectroscopy and thermal analysis. Their flammability was investigated by measuring limiting oxygen index values. The polymers are flame retardants and begin to lose weight in the 190 °C–231 °C range. Solid phosphorus- containing (copolyesters were complexed with lithium triflate and the resulting ionic conductivity was determined. Conductivities in the range of 10−7–10−8 S cm−1 were obtained.

  16. Determination of the Solid/Liquid Interface Shape and Resultant Radial Homogeneity in Directionally Solidified Hg(0.89)Mn(0.11)Te

    Price, M. W.; Scripa, R. N.; Lehoczky, S. L.; Szofran, F. R.; Hanson, B.


    Directional solidification and interrupted directional solidification experiments were used to determine tile shape of the solid/liquid interface and the resultant radial homogeneity in Hg(0.89)Mg(0.11)Te. For directionally solidified samples solidified at a rate of 0.09 microns/sec in a thermal gradient of 83 C/cm, a maximum of 0.006 molar percent MnTe radial variation across the Hg0.89)Mn(0.11)Te boules at specific locations was determined using an FTIR technique. This FTIR evaluation of the radial homogeneity also indicated an asymmetrical, convex interface shape during solidification. The asymmetrical, convex shape of the growth interface was confirmed by interrupted directional solidification experiments. These were performed under the same growth conditions as the normally completed directional solidification experiments except that the samples were quenched before the final growth transient was reached. In these experiments, etching and scanning X-ray fluorescence were used to reveal the shape of the solid/liquid interface. Microprobe analysis of composition gradients across the interface was used to confirm the authors' previous work in evaluating the segregation coefficient of Hg(0.89)Mn(0.11)Te alloy. Microprobe analysis of the interface region of the interrupted growth sample revealed a dendritic structure containing secondary and tertiary dendritic arms.

  17. Manipulation of small particles at solid liquid interface: light driven diffusioosmosis

    Feldmann, David; Maduar, Salim R.; Santer, Mark; Lomadze, Nino; Vinogradova, Olga I.; Santer, Svetlana


    The strong adhesion of sub-micron sized particles to surfaces is a nuisance, both for removing contaminating colloids from surfaces and for conscious manipulation of particles to create and test novel micro/nano-scale assemblies. The obvious idea of using detergents to ease these processes suffers from a lack of control: the action of any conventional surface-modifying agent is immediate and global. With photosensitive azobenzene containing surfactants we overcome these limitations. Such photo-soaps contain optical switches (azobenzene molecules), which upon illumination with light of appropriate wavelength undergo reversible trans-cis photo-isomerization resulting in a subsequent change of the physico-chemical molecular properties. In this work we show that when a spatial gradient in the composition of trans- and cis- isomers is created near a solid-liquid interface, a substantial hydrodynamic flow can be initiated, the spatial extent of which can be set, e.g., by the shape of a laser spot. We propose the concept of light induced diffusioosmosis driving the flow, which can remove, gather or pattern a particle assembly at a solid-liquid interface. In other words, in addition to providing a soap we implement selectivity: particles are mobilized and moved at the time of illumination, and only across the illuminated area.

  18. Photolithographic fabrication of solid-liquid core waveguides by thiol-ene chemistry

    Sagar, Kaushal; Gopalakrishnan, Nimi; Brøkner Christiansen, Mads; Kristensen, Anders; Ndoni, Sokol


    In this work we demonstrate an efficient and cleanroom compatible method for the fabrication of solid-liquid core waveguides based on nanoporous polymers. We have used thiol-ene photo-grafting to tune and pattern the hydrophilicity of an originally hydrophobic nanoporous 1, 2-polybutadiene. The generated refractive index contrast between the patterned water-filled volume and the surrounding empty hydrophobic porous polymer allows for light confinement within the water-filled volume—the solid-liquid core. The presented fabrication process is simple and fast. It allows a high degree of flexibility on the type and grade of surface chemistry imparted to the large nanoporous area depending upon the application. The fabrication does not need demanding chemical reaction conditions. Thus, it can be readily used on a standard silicon lithography bench. The propagation loss values reported in this work are comparable with literature values for state-of-the-art liquid-core waveguide devices. The demonstrated waveguide function added to the nanoporous polymer with a very high internal surface area makes the system interesting for many applications in different areas, such as diagnostics and bio-chemical sensing.

  19. Solid-liquid equilibria of binary mixtures of fluorinated ionic liquids.

    Teles, Ana Rita R; Correia, Helga; Maximo, Guilherme J; Rebelo, Luís P N; Freire, Mara G; Pereiro, Ana B; Coutinho, João A P


    Within ionic liquids, fluorinated ionic liquids (FILs) present unique physico-chemical properties and potential applications in several fields. However, the melting point of these neoteric compounds is usually higher due to the presence of fluorine atoms. This drawback may be resolved by, for instance, mixing different FILs to create eutectic mixtures. In this work, binary mixtures of fluoro-containing and fluorinated ionic liquids were considered with the aim of decreasing their melting temperatures as well as understanding and characterizing these mixtures and their phase transitions. Five FILs were selected, allowing the investigation of four binary mixtures, each of them with a common ion. Their solid-liquid and solid-solid equilibria were studied by differential scanning calorimetry and the non-ideality of the mixtures was investigated. Overall, a variety of solid-liquid equilibria with systems exhibiting eutectic behavior, polymorphs with solid-solid phase transitions, and the formation of intermediate compounds and solid solutions were surprisingly found. In addition to these intriguing behaviours, novel FILs with lower melting temperatures were obtained by the formation of binary systems, thus enlarging the application range of FILs at lower temperatures.

  20. A two-fluid model for reactive dilute solid-liquid mixtures with phase changes

    Reis, Martina Costa; Wang, Yongqi


    Based on the Eulerian spatial averaging theory and the Müller-Liu entropy principle, a two-fluid model for reactive dilute solid-liquid mixtures is presented. Initially, some averaging theorems and properties of average quantities are discussed and, then, averaged balance equations including interfacial source terms are postulated. Moreover, constitutive equations are proposed for a reactive dilute solid-liquid mixture, where the formation of the solid phase is due to a precipitation chemical reaction that involves ions dissolved in the liquid phase. To this end, principles of constitutive theory are used to propose linearized constitutive equations that account for diffusion, heat conduction, viscous and drag effects, and interfacial deformations. A particularity of the model is that the mass interfacial source term is regarded as an independent constitutive variable. The obtained results show that the inclusion of the mass interfacial source term into the set of independent constitutive variables permits to easily describe the phase changes associated with precipitation chemical reactions.

  1. Study on flow characteristics of solid/liquid system in lysozyme crystal growth

    CUI HaiLiang; YU Yong; CHEN WanChun; KANG Qi


    During the process of lysozyme protein crystallization with batch method, the macroscopic flow field of solid/liquid system was observed by particle image velocimetry (PIV). Furthermore, a normal growth rate of (110) face and local flow field around a single protein crystal were obtained by a long work distance microscope. The experimental results showed that the average velocity, the maximal velocity of macroscopic solid/liquid system and the velooity of local flow field around single protein crystal were fluctuant. The effective boundary layer thickness δeff, the concentration at the interface Gi and the characteristic velocity V were calculated using a convection-diffusion model. The results showed that the growth of lysozyme crystal in this experiment was dominated by interfacial kinetics rather than bulk transport, and the function of buoyancy-driven flow in bulk transport was small, however, the effect of bulk transport in crystal growth had a tendency to increase with the increase of lysozyme concentration. The calculated results also showed that the order of magnitude of shear force was about 10-21 N,which was much less than the bond force between the lysozyme molecules. Therefore the shear force induced by buoyancy-driven flows cannot remove the protein molecules from the interface of crystal.

  2. A two-fluid model for reactive dilute solid-liquid mixtures with phase changes

    Reis, Martina Costa; Wang, Yongqi


    Based on the Eulerian spatial averaging theory and the Müller-Liu entropy principle, a two-fluid model for reactive dilute solid-liquid mixtures is presented. Initially, some averaging theorems and properties of average quantities are discussed and, then, averaged balance equations including interfacial source terms are postulated. Moreover, constitutive equations are proposed for a reactive dilute solid-liquid mixture, where the formation of the solid phase is due to a precipitation chemical reaction that involves ions dissolved in the liquid phase. To this end, principles of constitutive theory are used to propose linearized constitutive equations that account for diffusion, heat conduction, viscous and drag effects, and interfacial deformations. A particularity of the model is that the mass interfacial source term is regarded as an independent constitutive variable. The obtained results show that the inclusion of the mass interfacial source term into the set of independent constitutive variables permits to easily describe the phase changes associated with precipitation chemical reactions.

  3. Performance evaluation of integrated solid-liquid wastes treatment technology in palm oil industry

    Amelia, J. R.; Suprihatin, S.; Indrasti, N. S.; Hasanudin, U.; Fujie, K.


    The oil palm industry significantly contributes to environmental degradation if without waste management properly. The newest alternative waste management that might be developed is by utilizing the effluent of POME anaerobic digestion with EFB through integrated anaerobic decomposition process. The aim of this research was to examine and evaluate the integrated solid-liquid waste treatment technology in the view point of greenhouse gasses emission, compost, and biogas production. POME was treated in anaerobic digester with loading rate about 1.65 gCOD/L/day. Treated POME with dosis of 15 and 20 L/day was sprayed to the anaerobic digester that was filled of 25 kg of EFB. The results of research showed that after 60 days, the C/N ratio of EFB decreased to 12.67 and 10.96 for dosis of treated POME 15 and 20 L/day, respectively. In case of 60 day decomposition, the integrated waste treatment technology could produce 51.01 and 34.34 m3/Ton FFB which was equivalent with 636,44 and 466,58 kgCO2e/ton FFB for dosis of treated POME 15 and 20 L/day, respectively. The results of research also showed that integrated solid-liquid wastes treatment technology could reduce GHG emission about 421.20 and 251.34 kgCO2e/ton FFB for dosis of treated POME 15 and 20 L/day, respectively.

  4. Toluene biodegradation in a solid/liquid system involving immobilized activated sludge and silicone oil as pollutant reservoir.

    Diz Castro, Manuel; Gómez-Díaz, Diego; Amrane, Abdeltif; Couvert, Annabelle


    A solid/liquid system involving activated sludge immobilized in an agar medium and a non-aqueous phase liquid containing the target pollutant has been considered to treat a model hydrophobic volatile organic compound, toluene. The positive impact of the use of a multiphase bioreactor is that the organic phase constitutes a pollutant reservoir and also helps to overcome possible pollutant toxicity. In addition and to overcome the drawbacks of the use of a solid organic phase (high pressure drop and low mass transfer) instead of a liquid organic phase, the considered solid phase was the aqueous. Consequently, silicone oil (polydimethylsiloxane) which showed its relevance for implementation in multiphase bioreactors was used. Promising results were observed from the analysis of toluene in the gaseous phase; for an initial amount of 2 g L(-1) related to the organic phase, a v/v ratio of 0.5 of the organic phase to the aqueous agar phase, total toluene consumption was observed in about 9 days, leading to a global biodegradation rate of approximately 3.1 mg L(-1) h(-1), namely in the range of values previously observed in liquid/liquid systems.

  5. Application of a novel type impinging streams reactor in solid-liquid enzyme reactions and modeling of residence time distribution using GDB model.

    Fatourehchi, Niloufar; Sohrabi, Morteza; Dabir, Bahram; Royaee, Sayed Javid; Haji Malayeri, Adel


    Solid-liquid enzyme reactions constitute important processes in biochemical industries. The isomerization of d-glucose to d-fructose, using the immobilized glucose isomerase (Sweetzyme T), as a typical example of solid-liquid catalyzed reactions has been carried out in one stage and multi-stage novel type of impinging streams reactors. Response surface methodology was applied to determine the effects of certain pertinent parameters of the process namely axial velocity (A), feed concentration (B), nozzles' flow rates (C) and enzyme loading (D) on the performance of the apparatus. The results obtained from the conversion of glucose in this reactor were much higher than those expected in conventional reactors, while residence time was decreased dramatically. Residence time distribution (RTD) in a one-stage impinging streams reactor was investigated using colored solution as the tracer. The results showed that the flow pattern in the reactor was close to that in a continuous stirred tank reactor (CSTR). Based on the analysis of flow region in the reactor, gamma distribution model with bypass (GDB) was applied to study the RTD of the reactor. The results indicated that RTD in the impinging streams reactor could be described by the latter model.

  6. A high pressure x-ray photoelectron spectroscopy experimental method for characterization of solid-liquid interfaces demonstrated with a Li-ion battery system

    Maibach, Julia; Xu, Chao; Gustafsson, Torbjörn; Edström, Kristina [Department of Chemistry–Ångström Laboratory, Uppsala University, Box 538, SE-751 21 Uppsala (Sweden); Eriksson, Susanna K. [Department of Chemistry–Ångström Laboratory, Uppsala University, Box 523, SE-751 20 Uppsala (Sweden); Åhlund, John [VG Scienta AB, Box 15120, SE-750 15 Uppsala (Sweden); Siegbahn, Hans; Rensmo, Håkan; Hahlin, Maria, E-mail: [Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden)


    We report a methodology for a direct investigation of the solid/liquid interface using high pressure x-ray photoelectron spectroscopy (HPXPS). The technique was demonstrated with an electrochemical system represented by a Li-ion battery using a silicon electrode and a liquid electrolyte of LiClO{sub 4} in propylene carbonate (PC) cycled versus metallic lithium. For the first time the presence of a liquid electrolyte was realized using a transfer procedure where the sample was introduced into a 2 mbar N{sub 2} environment in the analysis chamber without an intermediate ultrahigh vacuum (UHV) step in the load lock. The procedure was characterized in detail concerning lateral drop gradients as well as stability of measurement conditions over time. The X-ray photoelectron spectroscopy (XPS) measurements demonstrate that the solid substrate and the liquid electrolyte can be observed simultaneously. The results show that the solid electrolyte interphase (SEI) composition for the wet electrode is stable within the probing time and generally agrees well with traditional UHV studies. Since the methodology can easily be adjusted to various high pressure photoelectron spectroscopy systems, extending the approach towards operando solid/liquid interface studies using liquid electrolytes seems now feasible.

  7. Measurement of Peltier Heat at the Solid/Liquid Interface and Its Application to Crystal Growth I : Theoretical Approach

    Kim, I.H. [Chungju National University, Chungju (Korea); Jang, K.W. [Hanseo University,Seosan (Korea); Lee, D.H. [Yonsei University, Seoul (Korea)


    The Peltier heat absorbed or evolved at the solid/liquid interface in the unidirectional solidification process could contribute to the increase of temperature gradient in liquid and growth velocity, and the enhancement of crystal orientation. In this study, in order to measure the Peltier heat generated at the solid/liquid interface as a way of application to crystal growth, the thermoelectric effects were investigated on the temperature changes at the solid-and liquid-phase of the same material and its interface. Through the theoretical consideration, it was possible to separate sole Peltier, Thomson or Joule heat from the temperature changes due to current density, polarity, and temperature gradient. Thomson coefficient of solid- and liquid-phase as well as Peltier coefficient at the solid/liquid interface could be obtained. (author). 10 refs., 3 figs.

  8. Double multiple-relaxation-time lattice Boltzmann model for solid-liquid phase change with natural convection in porous media

    Liu, Qing; He, Ya-Ling


    In this paper, a double multiple-relaxation-time lattice Boltzmann model is developed for simulating transient solid-liquid phase change problems in porous media at the representative elementary volume scale. The model uses two different multiple-relaxation-time lattice Boltzmann equations, one for the flow field and the other for the temperature field with nonlinear latent heat source term. The model is based on the generalized non-Darcy formulation, and the solid-liquid interface is traced through the liquid fraction which is determined by the enthalpy-based method. The present model is validated by numerical simulations of conduction melting in a semi-infinite space, solidification in a semi-infinite corner, and convection melting in a square cavity filled with porous media. The numerical results demonstrate the efficiency and accuracy of the present model for simulating transient solid-liquid phase change problems in porous media.

  9. Double multiple-relaxation-time lattice Boltzmann model for solid-liquid phase change with natural convection in porous media

    Liu, Qing


    In this paper, a double multiple-relaxation-time lattice Boltzmann model is developed for simulating transient solid-liquid phase change problems in porous media at the representative elementary volume scale. The model uses two different multiple-relaxation-time lattice Boltzmann equations, one for the flow field and the other for the temperature field with nonlinear latent heat source term. The model is based on the generalized non-Darcy formulation, and the solid-liquid phase change interface is traced through the liquid fraction which is determined by the enthalpy method. The model is validated by numerical simulations of conduction melting in a semi-infinite space, solidification in a semi-infinite corner, and convection melting in a square cavity filled with porous media. The numerical results demonstrate the efficiency and accuracy of the present model for simulating transient solid-liquid phase change problems in porous media.

  10. Extraction and elemental analysis of Coleus forskohlii extract

    Haritha Kanne; Narayan Pandurang Burte; Prasanna, V; Ravi Gujjula


    Background: Coleus forskohlii Willd. is a popular traditional medicine used since ancient times for treatment of heart diseases, abdominal colic and respiratory disorders. Objective: The aim of this study was to characterize the root extract of the medicinal plant Coleus forskohlii. Materials and Methods: Dry roots of C. forskohlii were used to extract Forskolin using toluene as a solvent. Thus, obtained extract of C. forskohlii was standardized to 30% and used for further studies. Results: T...

  11. Biofilm formation at the solid-liquid and air-liquid interfaces by Acinetobacter species

    Seifert Harald


    Full Text Available Abstract Background The members of the genus Acinetobacter are Gram-negative cocobacilli that are frequently found in the environment but also in the hospital setting where they have been associated with outbreaks of nosocomial infections. Among them, Acinetobacter baumannii has emerged as the most common pathogenic species involved in hospital-acquired infections. One reason for this emergence may be its persistence in the hospital wards, in particular in the intensive care unit; this persistence could be partially explained by the capacity of these microorganisms to form biofilm. Therefore, our main objective was to study the prevalence of the two main types of biofilm formed by the most relevant Acinetobacter species, comparing biofilm formation between the different species. Findings Biofilm formation at the air-liquid and solid-liquid interfaces was investigated in different Acinetobacter spp. and it appeared to be generally more important at 25°C than at 37°C. The biofilm formation at the solid-liquid interface by the members of the ACB-complex was at least 3 times higher than the other species (80-91% versus 5-24%. In addition, only the isolates belonging to this complex were able to form biofilm at the air-liquid interface; between 9% and 36% of the tested isolates formed this type of pellicle. Finally, within the ACB-complex, the biofilm formed at the air-liquid interface was almost 4 times higher for A. baumannii and Acinetobacter G13TU than for Acinetobacter G3 (36%, 27% & 9% respectively. Conclusions Overall, this study has shown the capacity of the Acinetobacter spp to form two different types of biofilm: solid-liquid and air-liquid interfaces. This ability was generally higher at 25°C which might contribute to their persistence in the inanimate hospital environment. Our work has also demonstrated for the first time the ability of the members of the ACB-complex to form biofilm at the air-liquid interface, a feature that was not

  12. Neutron reflectivity as method to study in-situ adsorption of phospholipid layers to solid-liquid interfaces

    Gutberlet, Thomas; Klösgen, Beate Maria; Krastev, Rumen


    The use of neutron reflectivity as a method to study in-situ adsorption of phospholipid layers to solid-liquid interfaces was analyzed. The most important advantage of neutron reflectometry is the possibility to very the refractive index of the specific sample by isotope exchange, called contrast...... variation. It was observed that the method was capable of visualizing the adsorption of phospholipid layers to different solid-liquid interfaces and to resolve structural details at Angstroem resolution. The results depended strongly on a sufficiently good signal-to-noise ratio of the specific measurements...

  13. Solid-Liquid Equilibria for the Binary Mixtures 1,4-Xylene + Ethylbenzene and 1,4-Xylene + Toluene

    Huyghe, Raphaël; Rasmussen, Peter; Thomsen, Kaj


    Solid-liquid equilibrium (SLE) data for the binary mixtures 1,4-xylene + ethylbenzene, and 1,4-xylene + toluene have been measured using differential scanning calorimetry (DSC) in the temperature range from 133.15 K to 293.15 K.......Solid-liquid equilibrium (SLE) data for the binary mixtures 1,4-xylene + ethylbenzene, and 1,4-xylene + toluene have been measured using differential scanning calorimetry (DSC) in the temperature range from 133.15 K to 293.15 K....

  14. Analysis of antioxidants extracted from polypropylene by supercritical fluid extraction.

    Garde, J A; Catalá, R; Gavara, R


    Maximal potential migration of six antioxidants (AO) from five polypropylene (PP) formulations was determined by two supercritical fluid extraction (SFE) procedures, both of which contained static and dynamic steps. All analytical conditions affecting the extraction were studied and optimized using Irgafos 168 as standard. SFE was more efficient as temperature and fluid density increased. During the static step in which the samples were exposed to the fluid without flux, the introduction of hexane and methanol as fluid modifiers significantly improved the extraction. Hexane appears to facilitate polymer swelling while methanol solvates the antioxidants. In the dynamic step (in which the extraction actually occurs) time is the key parameter. Extraction for 90 min results in an efficiency of around 75%. The introduction of modifiers during this step (by an HPLC-SFE procedure) did not produce any significant improvement. When SFE was carried out on all samples, extraction efficiency was around 75% except for Irganox 1010 and Hostanox O3. The large molecular volume of these antioxidants may be responsible for the considerable reduction of extraction efficiency. Particle size and shape of polymer sample were also important. The greater the surface to volume ratio the greater the extraction efficiency.

  15. Synergistic extraction of gold from the refractory gold ore via ultrasound and chlorination-oxidation.

    Fu, Likang; Zhang, Libo; Wang, Shixing; Cui, Wei; Peng, Jinhui


    A synergistic extraction method for gold from the refractory gold ores via ultrasound and chlorination-oxidation was developed. The effects of solid-liquid ratio, extraction time, ultrasound power, NaClO concentration and NaOH concentration on the extraction rate of gold from the refractory gold ore were investigated. The optimum conditions were as follows: NaClO concentration of 1.5mol/L, NaOH concentration of 1.5mol/L, solid-liquid ratio of 5, ultrasound power of 200W and ultrasound time of 2h. Under the optimal conditions, 68.55% of gold was extracted. However, only 45.8% of gold was extracted after 6h without the ultrasound-assisted extraction. XRD and SEM were used to analyze the influence of ultrasound on the mineral properties and strengthening mechanism. The results showed that the interface layer was peeled, new surface was exposed, reaction resistance was reduced, the liquid-solid reaction was promoted and reaction speed was greatly improved under ultrasound. According to the results of range and variance analysis, the optimum leaching experiment with orthogonal design was almost identical with the optimum experiment of single factor. Among them, the ultrasound power was the most significant factors affecting leaching rate of gold. Compared with other extraction method, the synergistic extraction process decomposed completely sulfide and improved significantly the extraction rate of gold. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Hyperbranched polyglycerol/graphene oxide nanocomposite reinforced hollow fiber solid/liquid phase microextraction for measurement of ibuprofen and naproxen in hair and waste water samples.

    Rezaeifar, Zohreh; Es'haghi, Zarrin; Rounaghi, Gholam Hossein; Chamsaz, Mahmoud


    A new design of hyperbranched polyglycerol/graphene oxide nanocomposite reinforced hollow fiber solid/liquid phase microextraction (HBP/GO -HF-SLPME) coupled with high performance liquid chromatography used for extraction and determination of ibuprofen and naproxen in hair and waste water samples. The graphene oxide first synthesized from graphite powders by using modified Hummers approach. The surface of graphene oxide was modified using hyperbranched polyglycerol, through direct polycondensation with thionyl chloride. The ready nanocomposite later wetted by a few microliter of an organic solvent (1-octanol), and then applied to extract the target analytes in direct immersion sampling mode.After the extraction process, the analytes were desorbed with methanol, and then detected via high performance liquid chromatography (HPLC). The experimental setup is very simple and highly affordable. The main factors influencing extraction such as; feed pH, extraction time, aqueous feed volume, agitation speed, the amount of functionalized graphene oxide and the desorption conditions have been examined in detail. Under the optimized experimental conditions, linearity was observed in the range of 5-30,000ngmL(-1) for ibuprofen and 2-10,000ngmL(-1) for naproxen with correlation coefficients of 0.9968 and 0.9925, respectively. The limits of detection were 2.95ngmL(-1) for ibuprofen and 1.51ngmL(-1) for naproxen. The relative standard deviations (RSDs) were found to be less than 5% (n=5).

  17. Extracting aluminum from dross tailings

    Amer, A. M.


    Aluminum dross tailings, an industrial waste, from the Egyptian Aluminium Company (Egyptalum) was used to produce two types of alums: aluminum-sulfate alum [itAl2(SO4)3.12H2O] and ammonium-aluminum alum [ (NH 4)2SO4AL2(SO4)3.24H2O]. This was carried out in two processes. The first process is leaching the impurities using diluted H2SO4 with different solid/liquid ratios at different temperatures to dissolve the impurities present in the starting material in the form of solute sulfates. The second process is the extraction of aluminum (as aluminum sulfate) from the purifi ed aluminum dross tailings thus produced. The effects of temperature, time of reaction, and acid concentration on leaching and extraction processes were studied. The product alums were analyzed using x-ray diffraction and thermal analysis techniques.

  18. Solid-liquid phase equilibria of the Gaussian core model fluid.

    Mausbach, Peter; Ahmed, Alauddin; Sadus, Richard J


    The solid-liquid phase equilibria of the Gaussian core model are determined using the GWTS [J. Ge, G.-W. Wu, B. D. Todd, and R. J. Sadus, J. Chem. Phys. 119, 11017 (2003)] algorithm, which combines equilibrium and nonequilibrium molecular dynamics simulations. This is the first reported use of the GWTS algorithm for a fluid system displaying a reentrant melting scenario. Using the GWTS algorithm, the phase envelope of the Gaussian core model can be calculated more precisely than previously possible. The results for the low-density and the high-density (reentrant melting) sides of the solid state are in good agreement with those obtained by Monte Carlo simulations in conjunction with calculations of the solid free energies. The common point on the Gaussian core envelope, where equal-density solid and liquid phases are in coexistence, could be determined with high precision.

  19. Intermetallic Compound Formation Mechanisms for Cu-Sn Solid-Liquid Interdiffusion Bonding

    Liu, H.; Wang, K.; Aasmundtveit, K. E.; Hoivik, N.


    Cu-Sn solid-liquid interdiffusion (SLID) bonding is an evolving technique for wafer-level packaging which features robust, fine pitch and high temperature tolerance. The mechanisms of Cu-Sn SLID bonding for wafer-level bonding and three-dimensional (3-D) packaging applications have been studied by analyzing the microstructure evolution of Cu-Sn intermetallic compounds (IMCs) at elevated temperature up to 400°C. The bonding time required to achieve a single IMC phase (Cu3Sn) in the final interconnects was estimated according to the parabolic growth law with consideration of defect-induced deviation. The effect of predominantly Cu metal grain size on the Cu-Sn interdiffusion rate is discussed. The temperature versus time profile (ramp rate) is critical to control the morphology of scallops in the IMC. A low temperature ramp rate before reaching the bonding temperature is believed to be favorable in a SLID wafer-level bonding process.

  20. Modeling of ultrasound transmission through a solid-liquid interface comprising a network of gas pockets

    Paumel, K.; Moysan, J.; Chatain, D.; Corneloup, G.; Baqué, F.


    Ultrasonic inspection of sodium-cooled fast reactor requires a good acoustic coupling between the transducer and the liquid sodium. Ultrasonic transmission through a solid surface in contact with liquid sodium can be complex due to the presence of microscopic gas pockets entrapped by the surface roughness. Experiments are run using substrates with controlled roughness consisting of a network of holes and a modeling approach is then developed. In this model, a gas pocket stiffness at a partially solid-liquid interface is defined. This stiffness is then used to calculate the transmission coefficient of ultrasound at the entire interface. The gas pocket stiffness has a static, as well as an inertial component, which depends on the ultrasonic frequency and the radiative mass.

  1. Influence of solid-liquid separation strategy on biogas yield from a stratified swine production system.

    Cestonaro do Amaral, André; Kunz, Airton; Radis Steinmetz, Ricardo Luis; Scussiato, Lucas Antunes; Tápparo, Deisi Cristina; Gaspareto, Taís Carla


    As the fourth largest swine producer and exporter, Brazil has increased its participation in the global swine production market. Generally, these units concentrate a large number of animals and generate effluents that must be correctly managed to prevent environmental impacts, being anaerobic digestion is an interesting alternative for treating these effluents. The low-volatile solid concentration in the manure suggests the need for solid-liquid separation as a tool to improve the biogas generation capacity. This study aimed to determine the influence of simplified and inexpensive solid-liquid separation strategies (screening and settling) and the different manures produced during each swine production phase (gestating and farrowing sow houses, nursery houses and finishing houses) on biogas and methane yield. We collected samples in two gestating sow houses (GSH-a and GSH-b), two farrowing sow houses (FSH-a and FSH-b), a nursery house (NH) and a finishing house (FH). Biochemical methane potential (BMP) tests were performed according to international standard procedures. The settled sludge fraction comprised 20-30% of the raw manure volume, which comprises 40-60% of the total methane yield. The methane potential of the settled sludge fraction was approximately two times higher than the methane potential of the supernatant fraction. The biogas yield differed among the raw manures from different swine production phases (GSH-a 326.4 and GSH-b 577.1; FSH-a 860.1 and FSH-b 479.2; NH -970.2; FH 474.5 NmLbiogas.gVS(-1)). The differences were relative to the production phase (feed type and feeding techniques) and the management of the effluent inside the facilities (water management). Brazilian swine production has increased his participation in the global market, been the fourth producer and the fourth exporter. The segregation of swine production in multiple sites has increased its importance, due to the possibilities to have more specialized units. Generally, these units

  2. Physics of solid-liquid interfaces: From the Young equation to the superhydrophobicity (Review Article)

    Bormashenko, Edward


    The state-of-art in the field of physics of phenomena occurring at solid/liquid interfaces is presented. The notions of modern physics of wetting are introduced and discussed including: the contact angle hysteresis, disjoining pressure and wetting transitions. The physics of low temperature wetting phenomena is treated. The general variational approach to interfacial problems, based on the application of the transversality conditions to variational problems with free endpoints is presented. It is demonstrated that main equations, predicting contact angles, namely the Young, Wenzel, and Cassie-Baxter equations arise from imposing the transversality conditions on the appropriate variational problem of wetting. Recently discovered effects such as superhydrophobicity, the rose petal effect and the molecular dynamic of capillarity are reviewed.

  3. The effects of solid-liquid interfacial tension on the settlement of sediment flocs

    Jianglin, Z


    In this paper, the effects of interfacial tension between the sediment solid particle and liquid on the settlement of sediment flocs are investigated. After a discussion of mechanical and physical chemistry, we give a settling velocity expression including such dynamical information of the floc growth as interfacial tension and primary particle size \\textit{etc.}. The resulting expression indicates the average settling velocity of sediment flocs increases with increasing solid-liquid interfacial tension in a form of power law and deceases with the primary particle size. We report on a general method for analyzing settling behaviors of sediment flocs under different flocculation conditions and verify the rationality of the assumption of tension-induced flocculation by fitting typical experimental data to the electrolyte concentration-dependent sedimentation model which can follow from the relationship between interfacial tension and electrolyte concentration.

  4. A QCM study on the adsorption of colloidal laponite at the solid/liquid interface.

    Xu, Dan; Hodges, Chris; Ding, Yulong; Biggs, Simon; Brooker, Anju; York, David


    The adsorption of colloidal laponite at the solid/liquid interface on various substrates and over a range of laponite concentrations (10-1000 ppm) has been investigated. Although a wide range of surfaces were studied, only on a positively charged poly(diallyldimethylammonium chloride) (PDADMAC) surface was any adsorption of the laponite observed. This shows that when fully wetted, laponite adsorption depends primarily on the surface charge rather than the degree of hydrophobicity of the surface. The adsorption of spherical Ludox silica nanoparticles on PDADMAC surfaces was also examined for comparison with the disklike laponite. The QCM data for both laponite and Ludox show strong adsorption on PDADMAC surfaces; however, larger frequency shifts were seen for Ludox than laponite at all concentrations tested. Within the concentration range examined in this work, the dissipation data from the QCM suggested a simple monolayer formation for Ludox but a monolayer to multilayer transition for laponite as the concentration increases.

  5. Study of Solid-Liquid Ratio of Fly Ash Geopolymer as Water Absorbent Material

    Angga Prasetya Fandi


    Full Text Available Geopolymer has been synthesized from fly ash to be applicated as water absorbent material. This research conducted to determine the ability of geopolymer to abrsop water by variation of solid – liquid ratio at optimum molarity of NaOH; 3 M. In this research, the synthesis of geopolymer was conducted at the variation of solid-liquid ratio; 60:40, 65:35, 70:30, and 75:25. Result of the treatment were characterized by XRD and SEM to compare the geopolymer structure. Water absorption capacity was measured by immersing the geopolymer specimens in water for 24 hours. Based on the result, solid – liquid ratio with maximum water absorbed was 70:30 with 13,04 wt%.

  6. Force response of actively deformed polymer microdroplets: dependence on the solid/liquid boundary condition

    Heppe, Jonas; McGraw, Joshua D.; Bennewitz, Roland; Jacobs, Karin


    In fluid dynamics, the solid/liquid boundary condition can play a major role in the flow behavior of a liquid. For example, in the dewetting of identical polymer films on weak slip or strong slip substrates, large qualitative and quantitative differences are observed. Therefore, when applying an external load to a liquid resting on such substrates, the measured reaction forces and the ensuing flow should also depend on the boundary condition. We present atomic force microscopy measurements in which the reaction force of a cantilever is measured as the tip pierces liquid polymer micron sized droplets and films. These indentations are done on substrates with tuned slip. Accessing the size, depth and rate dependence of the resulting force distance curves, we show an influence of the slip condition on the dissipated energy and adhesion.

  7. Estimation of the curvature of the solid liquid interface during Bridgman crystal growth

    Barat, Catherine; Duffar, Thierry; Garandet, Jean-Paul


    An approximate solution for the solid/liquid interface curvature due to the crucible effect in crystal growth is derived from simple heat flux considerations. The numerical modelling of the problem carried out with the help of the finite element code FIDAP supports the predictions of our analytical expression and allows to identify its range of validity. Experimental interface curvatures, measured in gallium antimonide samples grown by the vertical Bridgman method, are seen to compare satisfactorily to analytical and numerical results. Other literature data are also in fair agreement with the predictions of our models in the case where the amount of heat carried by the crucible is small compared to the overall heat flux.

  8. Bilayer molecular assembly at a solid/liquid interface as triggered by a mild electric field.

    Zheng, Qing-Na; Liu, Xuan-He; Liu, Xing-Rui; Chen, Ting; Yan, Hui-Juan; Zhong, Yu-Wu; Wang, Dong; Wan, Li-Jun


    The construction of a spatially defined assembly of molecular building blocks, especially in the vertical direction, presents a great challenge for surface molecular engineering. Herein, we demonstrate that an electric field applied between an STM tip and a substrate triggered the formation of a bilayer structure at the solid-liquid interface. In contrast to the typical high electric-field strength (10(9)  V m(-1) ) used to induce structural transitions in supramolecular assemblies, a mild electric field (10(5)  V m(-1) ) triggered the formation of a bilayer structure of a polar molecule on top of a nanoporous network of trimesic acid on graphite. The bilayer structure was transformed into a monolayer kagome structure by changing the polarity of the electric field. This tailored formation and large-scale phase transformation of a molecular assembly in the perpendicular dimension by a mild electric field opens perspectives for the manipulation of surface molecular nanoarchitectures.

  9. First-principles molecular dynamics simulations at solid-liquid interfaces with a continuum solvent

    Sanchez, Veronica M; Scherlis, Damian A


    Continuum solvent models have become a standard technique in the context of electronic structure calculations, yet, no implementations have been reported capable to perform molecular dynamics at solid-liquid interfaces. We propose here such a continuum approach in a DFT framework, using plane-waves basis sets and periodic boundary conditions. Our work stems from a recent model designed for Car-Parrinello simulations of quantum solutes in a dielectric medium [J. Chem. Phys. 124, 74103 (2006)], for which the permittivity of the solvent is defined as a function of the electronic density of the solute. This strategy turns out to be inadequate for systems extended in two dimensions, by introducing new term in the Kohn-Sham potential which becomes unphysically large at the interfacial region, seriously affecting the convergence. If the dielectric medium is properly redefined as a function of the atomic coordinates, a good convergence is obtained and the constant of motion is conserved during the molecular dynamics ...

  10. Solid/liquid phase diagram of the ammonium sulfate/succinic acid/water system.

    Pearson, Christian S; Beyer, Keith D


    We have studied the low-temperature phase diagram and water activities of the ammonium sulfate/succinic acid/water system using differential scanning calorimetry and infrared spectroscopy of thin films. Using the results from our experiments, we have mapped the solid/liquid ternary phase diagram, determined the water activities based on the freezing point depression, and determined the ice/succinic acid phase boundary as well as the ternary eutectic composition and temperature. We also compared our results to the predictions of the extended AIM aerosol thermodynamics model (E-AIM) and found good agreement for the ice melting points in the ice primary phase field of this system; however, differences were found with respect to succinic acid solubility temperatures. We also compared the results of this study with those of previous studies that we have published on ammonium sulfate/dicarboxylic acid/water systems.

  11. Ginzburg-Landau theory for the solid-liquid interface of bcc elements

    Shih, W. H.; Wang, Z. Q.; Zeng, X. C.; Stroud, D.


    Consideration is given to a simple order-parameter theory for the interfacial tension of body-centered-cubic solids in which the principal order parameter is the amplitude of the density wave at the smallest nonzero reciprocal-lattice vector of the solid. The parameters included in the theory are fitted to the measured heat of fusion, melting temperature, and solid-liquid density difference, and to the liquid structure factor and its temperature derivative at freezing. Good agreement is found with experiment for Na and Fe and the calculated anisotropy of the surface tension among different crystal faces is of the order of 2 percent. On the basis of various assumptions about the universal behavior of bcc crystals at melting, the formalism predicts that the surface tension is proportional to the heat of fusion per surface atom.

  12. Experimental Study on Scale-Up of Solid-Liquid Stirred Tank with an Intermig Impeller

    Zhao, Hongliang; Zhao, Xing; Zhang, Lifeng; Yin, Pan


    The scale-up of a solid-liquid stirred tank with an Intermig impeller was characterized via experiments. Solid concentration, impeller just-off-bottom speed and power consumption were measured in stirred tanks of different scales. The scale-up criteria for achieving the same effect of solid suspension in small-scale and large-scale vessels were evaluated. The solids distribution improves if the operating conditions are held constant as the tank is scaled-up. The results of impeller just-off-bottom speed gave X = 0.868 in the scale-up relationship ND X = constant. Based on this criterion, the stirring power per unit volume obviously decreased at N = N js, and the power number ( N P) was approximately equal to 0.3 when the solids are uniformly distributed in the vessels.

  13. Sediment-copper distributions in hyper-concentrated turbulent solid-liquid system

    YANG Jun; NI Jin-ren


    This study presents a special problem on vertical distribution for sediment and copper in hyper-concentrated turbulent solid-liquid system that is essentially different from the ordinary low-concentrated turbulent system. A resonance type turbulent simulation equipment is used for the experimental study in which a vertically uniform turbulent field of the mixture of loess and water is produced in a testing cylinder with a grille stirrer that moves up and down harmoniously with varying vibration frequencies. In order to compare the variations of the vertical profiles of sediment and copper in low- and hyper-concentrated solid-liquid system, different scenarios for input sediment content ranging from 5 to 800 kg/m3 was considered in the experimental studies. It was found that solids copper content increases with input sediment content, S0, and reaches its peak as S0 goes to 10 kg/m3 and then decreases rapidly with increasing input sediment content. Such a behavior is possibly resulted from the joint effect of the specific adsorption of copper on loess, precipitation of carbonate and hydroxide of copper due to high carbonate content in the loess and the so-called "particulate concentration effect" due to the present of the sediment variation in water. The vertical sediment concentration distribution resulted from the uniform turbulence is generally uniform, but slight non-uniformity does occur as sediment concentration exceeds certain value. However, the vertical concentration distributions of soluble copper seem not affected much by the variation of sediment concentrations.

  14. Static and dynamic electrowetting of an ionic liquid in a solid/liquid/liquid system.

    Paneru, Mani; Priest, Craig; Sedev, Rossen; Ralston, John


    A droplet of an ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate, bmim.BF(4)) is immersed in an immiscible liquid (n-hexadecane) and electrowetted on a flat Teflon AF1600-coated ITO electrode. The static contact angle decreases significantly when voltage is applied between the droplet and the electrode: from 145 degrees down to 50 degrees (with DC voltage) and 15 degrees (with AC voltage). The electrowetting curves (contact angle versus voltage) are similar to the ones obtained in other solid/liquid/vapor and solid/liquid/liquid systems: symmetric with respect to zero voltage and correctly described by Young-Lippmann equation below saturation. The reversibility is excellent and contact angle hysteresis is minimal (approximately 2 degrees). The step size used in applying the DC voltage and the polarity of the voltage are unimportant. The saturation contact angle cannot be predicted with the simple zero-interfacial tension theory. Spreading (after applying a DC voltage) and retraction (after switching off the voltage) of the droplet is monitored. The base area of the droplet varies exponentially during wetting (exponential saturation) and dewetting (exponential decay). The characteristic time is 20 ms for spreading and 35 ms for retraction (such asymmetry is not observed with water-glycerol mixtures of a similar viscosity). The spreading kinetics (dynamic contact angle versus contact line speed) can be described by the hydrodynamic model (Voinov's equation) for small contact angles and by the molecular-kinetic model (Blake's equation) for large contact angles. The role of viscous and molecular dissipation follows the scheme outlined by Brochard-Wyart and de Gennes.

  15. Extraction and analysis of polyphenols: recent trends.

    Ajila, C M; Brar, S K; Verma, M; Tyagi, R D; Godbout, S; Valéro, J R


    In recent years, there has been an increasing interest in diets rich in fruits and vegetables and this is mostly due to their presumed role in the prevention of various degenerative diseases, such as cancer and cardiovascular diseases. This is mainly due to the presence of bioactive compounds, such as polyphenols, carotenoids, among others. Polyphenols are one of the main classes of secondary metabolites derived from plants offering several health benefits resulting in their use as functional foods. Prior to the use of these polyphenols in specific applications, such as food, pharmaceutical, and the cosmetic industries, they need to be extracted from the natural matrices, then analyzed and characterized. The development of an efficient procedure for the extraction, proper analysis, and characterization of phenolic compounds from different sources is a challenging task due to the structural diversity of phenolic compounds, a complex matrix, and their interaction with other cellular components. In this light, this review discusses different methods of extraction, analysis, and the structural characterization of polyphenolic compounds.

  16. Statistical optimization of aqueous extraction of pectin from waste durian rinds.

    Maran, J Prakash


    The objectives of this present study was to investigate and optimize the aqueous extraction conditions such as solid-liquid (SL) ratio (1:5-1:15 g/ml), pH (2-3), extraction time (20-60 min) and extraction temperature (75-95 °C) on maximum extraction of pectin from durian rinds using four factors, three levels Box-Behnken response design. The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis and analyzed by analysis of variance (ANOVA). The optimum extraction condition was found to be as follows: SL ratio of 1:10 g/ml, pH of 2.8, extraction time of 43 min and extraction temperature of 86 °C respectively. Under the optimal conditions, the experimental pectin yield (9.1%) was well correlated with predicted yield (9.3%).

  17. Analysis of Water Extraction From Lunar Regolith

    Hegde, U.; Balasubramaniam, R.; Gokoglu, S.


    Distribution of water concentration on the Moon is currently an area of active research. Recent studies suggest the presence of ice particles, and perhaps even ice blocks and ice-cemented regolith on the Moon. Thermal extraction of the in-situ water is an attractive means of sa tisfying water requirements for a lunar mission. In this paper, a model is presented to analyze the processes occurring during the heat-up of icy regolith and extraction of the evolved water vapor. The wet regolith is assumed to be present in an initially evacuated and sealed cell which is subsequently heated. The first step of the analysis invol ves calculating the gradual increase of vapor pressure in the closed cell as the temperature is raised. Then, in the second step, the cell is evacuated to low pressure (e.g., vacuum), allowing the water vapor to leave the cell and be captured. The parameters affecting water vap or pressure build-up and evacuation for the purpose of extracting water from lunar regolith are discussed in the paper. Some comparisons wi th available experimental measurements are also made.

  18. Supercritical extraction of oleaginous: parametric sensitivity analysis

    Santos M.M.


    Full Text Available The economy has become universal and competitive, thus the industries of vegetable oil extraction must advance in the sense of minimising production costs and, at the same time, generating products that obey more rigorous patterns of quality, including solutions that do not damage the environment. The conventional oilseed processing uses hexane as solvent. However, this solvent is toxic and highly flammable. Thus the search of substitutes for hexane in oleaginous extraction process has increased in the last years. The supercritical carbon dioxide is a potential substitute for hexane, but it is necessary more detailed studies to understand the phenomena taking place in such process. Thus, in this work a diffusive model for semi-continuous (batch for the solids and continuous for the solvent isothermal and isobaric extraction process using supercritical carbon dioxide is presented and submitted to a parametric sensitivity analysis by means of a factorial design in two levels. The model parameters were disturbed and their main effects analysed, so that it is possible to propose strategies for high performance operation.

  19. SPS extraction kicker magnet thermal analysis

    Timmins, M


    As the SPS accelerator will be used for the CNGS project and as LHC injector, the proton beams passing through its extraction kickers will have a much higher intensity than in the past. The image currents generated by this beam may provoke a temperature increase in the magnet's ferrite core to temperatures above the Curie temperature, unless the heat produced is effectively removed. A further complication arises from the fact that a high voltage is applied to the ferrites. The solution adopted consists in transferring the heat via Aluminium Nitride insulators to a water cooling circuit. The heat transfer analysis and the calculated thermal distribution of the magnet are presented.

  20. Numerical Calculation of the Drag Force Acting on a Solid Particle Pushed by a Solid/Liquid Interface

    Catalina, Adrian V.; Stefanescu, Doru M.; Sen, Subhayu


    The distribution of insoluble particles in a metal casting depends primarily on the interaction of the particles with the solid/liquid interface (SLI) during the solidification process. The balance of the forces acting on the particle essentially determines whether a particle will be engulfed or pushed by the SLI. An important component of this force balance is the drag force generated by the particle motion in front of the SLI. Previously developed mathematical models for particle/SLI interaction made use of steady-state solutions of this force provided by the lubrication theory. However, our numerical model based on the SLI tracking approach shows that the steady-state approach is inappropriate to model the interaction process and that at steady-state the theoretical solution underestimates the drag force. It was found that regression analysis of steady-state numerical solutions for cylindrical particles moving normal to a flat SLI gives a relationship of the form: Abstract The distribution of insoluble particles in a metal casting depends primarily on the interaction of the particles with the solid/liquid interface (SLI) during the solidification process. The balance of the forces acting on the particle essentially determines whether a particle will be engulfed or pushed by the SLI. An important component of this force balance is the drag force generated by the particle motion in front of the SLI. Previously developed mathematical models for particle/SLI interaction made use of steady-state solutions of this force provided by the lubrication theory. However, our numerical model based on the SLI tracking approach shows that the steady-state approach is inappropriate to model the interaction process and that at steady-state the theoretical solution underestimates the drag force. It was found that regression analysis of steady-state numerical solutions for cylindrical particles moving normal to a flat SLI gives a relationship of the form: F(sub D, sup num) =sqoare

  1. Molecular dynamics study of solid-liquid heat transfer and passive liquid flow

    Yesudasan Daisy, Sumith

    equilibrium canonical ensemble (NVT) is simulated using thermostat algorithms. For research in heat transfer involving solid liquid interaction, we need to perform non equilibrium MD (NEMD) simulations. In such NEMD simulations, the methods used for simulating heating from a surface is very important and must capture proper physics and thermodynamic properties. Development of MD simulation techniques to simulate solid-liquid heating and the study of fundamental mechanism of passive flow is the main focus of this thesis. An accurate surface-heating algorithm was developed for water which can now allow the study of a whole new set of fundamental heat transfer problems at the nanoscale like surface heating/cooling of droplets, thin-films, etc. The developed algorithm is implemented in the in-house developed C++ MD code. A direct two dimensional local pressure estimation algorithm is also formulated and implemented in the code. With this algorithm, local pressure of argon and platinum interaction is studied. Also, the surface tension of platinum-argon (solid-liquid) was estimated directly from the MD simulations for the first time. Contact angle estimation studies of water on platinum, and argon on platinum were also performed. A thin film of argon is kept above platinum plate and heated in the middle region, leading to the evaporation and pressure reduction thus creating a strong passive flow in the near surface region. This observed passive liquid flow is characterized by estimating the pressure, density, velocity and surface tension using Eulerian mapping method. Using these simulation, we have demonstrated the fundamental nature and origin of surface-driven passive flow. Heat flux removed from the surface is also estimated from the results, which shows a significant improvement can be achieved in thermal management of electronic devices by taking advantage of surface-driven strong passive liquid flow. Further, the local pressure of water on silicon di-oxide surface is

  2. Order-parameter-aided temperature-accelerated sampling for the exploration of crystal polymorphism and solid-liquid phase transitions

    Yu, Tang-Qing, E-mail:; Vanden-Eijnden, Eric, E-mail: [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States); Chen, Pei-Yang; Chen, Ming [Department of Chemistry, New York University, New York, New York 10003 (United States); Samanta, Amit [Program in Applied and Computational Mathematics, Princeton University, Princeton, New Jersey 08544, USA and Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Tuckerman, Mark, E-mail: [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States); Department of Chemistry, New York University, New York, New York 10003 (United States); NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai 200062 (China)


    The problem of predicting polymorphism in atomic and molecular crystals constitutes a significant challenge both experimentally and theoretically. From the theoretical viewpoint, polymorphism prediction falls into the general class of problems characterized by an underlying rough energy landscape, and consequently, free energy based enhanced sampling approaches can be brought to bear on the problem. In this paper, we build on a scheme previously introduced by two of the authors in which the lengths and angles of the supercell are targeted for enhanced sampling via temperature accelerated adiabatic free energy dynamics [T. Q. Yu and M. E. Tuckerman, Phys. Rev. Lett. 107, 015701 (2011)]. Here, that framework is expanded to include general order parameters that distinguish different crystalline arrangements as target collective variables for enhanced sampling. The resulting free energy surface, being of quite high dimension, is nontrivial to reconstruct, and we discuss one particular strategy for performing the free energy analysis. The method is applied to the study of polymorphism in xenon crystals at high pressure and temperature using the Steinhardt order parameters without and with the supercell included in the set of collective variables. The expected fcc and bcc structures are obtained, and when the supercell parameters are included as collective variables, we also find several new structures, including fcc states with hcp stacking faults. We also apply the new method to the solid-liquid phase transition in copper at 1300 K using the same Steinhardt order parameters. Our method is able to melt and refreeze the system repeatedly, and the free energy profile can be obtained with high efficiency.

  3. Layered inorganic-organic hybrid with talc-like structure for cation removal at the solid/liquid interface

    Badshah, Syed [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP (Brazil); Airoldi, Claudio, E-mail: [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP (Brazil)


    Graphical abstract: A lamellar inorganic-organic hybrid with talc-like structure has been synthesized through a single sol-gel step. Highlights: Black-Right-Pointing-Pointer New silylating agent isolated from acrylamide includes basic centers attached to enlarged chain. Black-Right-Pointing-Pointer Lamellar inorganic-organic talc-like structure has been synthesized through a single sol-gel step. Black-Right-Pointing-Pointer High basal distance accommodates the pendant chain in the cavities only in inclined disposition. Black-Right-Pointing-Pointer The pendant chain sorbs spontaneously and favorable cations as demonstrated by thermodynamic data. - Abstract: A new silylating agent N-((3-(3-(trimethoxysilyl)propylthio)propanamido)methyl)acrylamide synthesized from the reaction of N,N-methylenebisacrylamide and 3-mercaptopropyltrimethoxysilane yielded layered inorganic-organic talc-like magnesium phyllosilicate through the sol-gel process. Elemental analysis data based on sulfur demonstrated incorporation of 2.70 mmol g{sup -1} of organic moiety inside the lamellar cavities and the X-ray diffraction patterns confirmed the talc-like structure with a basal distance of 2.11 nm. Infrared spectroscopy, {sup 13}C and {sup 29}Si NMR in the solid state are in agreement with the presence of organic chains covalently bonded to the inorganic lamellar framework, as also supported by the presence of T{sup n} silicon species. Nitrogen, oxygen and sulfur basic centers sorb divalent lead, copper and cobalt cations with maximum capacity of 5.30, 3.82 and 1.60 mmol g{sup -1}. The thermodynamic data for cation/basic center interactions at the solid/liquid interface were determined through calorimetric titration with exothermic enthalpy, negative Gibbs energy and positive entropy, as expected for spontaneous and favorable reaction conditions.

  4. Performance and techno-economic assessment of several solid-liquid separation technologies for processing dilute-acid pretreated corn stover.

    Sievers, David A; Tao, Ling; Schell, Daniel J


    Solid-liquid separation of pretreated lignocellulosic biomass slurries is a critical unit operation employed in several different processes for production of fuels and chemicals. An effective separation process achieves good recovery of solute (sugars) and efficient dewatering of the biomass slurry. Dilute acid pretreated corn stover slurries were subjected to pressure and vacuum filtration and basket centrifugation to evaluate the technical and economic merits of these technologies. Experimental performance results were used to perform detailed process simulations and economic analysis using a 2000 tonne/day biorefinery model to determine differences between the various filtration methods and their process settings. The filtration processes were able to successfully separate pretreated slurries into liquor and solid fractions with estimated sugar recoveries of at least 95% using a cake washing process. A continuous vacuum belt filter produced the most favorable process economics.

  5. Insulin Aggregation at a Dynamic Solid-Liquid-Air Triple Interface.

    Frachon, Thibaut; Bruckert, Franz; Le Masne, Quentin; Monnin, Emmanuel; Weidenhaupt, Marianne


    Therapeutic proteins are privileged in drug development because of their exquisite specificity, which is due to their three-dimensional conformation in solution. During their manufacture, storage, and delivery, interactions with material surfaces and air interfaces are known to affect their stability. The growing use of automated devices for handling and injection of therapeutics increases their exposure to protocols involving intermittent wetting, during which the solid-liquid and liquid-air interfaces meet at a triple contact line, which is often dynamic. Using a microfluidic setup, we analyze the effect of a moving triple interface on insulin aggregation in real time over a hydrophobic surface. We combine thioflavin T fluorescence and reflection interference microscopy to concomitantly monitor insulin aggregation and the morphology of the liquid as it dewets the surface. We demonstrate that insulin aggregates in the region of a moving triple interface and not in regions submitted to hydrodynamic shear stress alone, induced by the moving liquid. During dewetting, liquid droplets form on the surface anchored by adsorbed proteins, and the accumulation of amyloid aggregates is observed exclusively as fluorescent rings growing eccentrically around these droplets. The fluorescent rings expand until the entire channel surface sweeped by the triple interface is covered by amyloid fibers. On the basis of our experimental results, we propose a model describing the growth mechanism of insulin amyloid fibers at a moving triple contact line, where proteins adsorbed at a hydrophobic surface are exposed to the liquid-air interface.

  6. Dynamic covalent chemistry of bisimines at the solid/liquid interface monitored by scanning tunnelling microscopy

    Ciesielski, Artur; El Garah, Mohamed; Haar, Sébastien; Kovaříček, Petr; Lehn, Jean-Marie; Samorì, Paolo


    Dynamic covalent chemistry relies on the formation of reversible covalent bonds under thermodynamic control to generate dynamic combinatorial libraries. It provides access to numerous types of complex functional architectures, and thereby targets several technologically relevant applications, such as in drug discovery, (bio)sensing and dynamic materials. In liquid media it was proved that by taking advantage of the reversible nature of the bond formation it is possible to combine the error-correction capacity of supramolecular chemistry with the robustness of covalent bonding to generate adaptive systems. Here we show that double imine formation between 4-(hexadecyloxy)benzaldehyde and different α,ω-diamines as well as reversible bistransimination reactions can be achieved at the solid/liquid interface, as monitored on the submolecular scale by in situ scanning tunnelling microscopy imaging. Our modular approach enables the structurally controlled reversible incorporation of various molecular components to form sophisticated covalent architectures, which opens up perspectives towards responsive multicomponent two-dimensional materials and devices.


    F.V. Hanson; J.V. Fletcher; Karthik R.


    A methodology was developed using an FT-IR spectroscopic technique to obtain solid-liquid equilibria (SLE) data for mixtures of heavy hydrocarbons in significantly lighter hydrocarbon diluents. SLE was examined in multiple Model Oils that were assembled to simulate waxes. The various Model oils were comprised of C-30 to C-44 hydrocarbons in decane. The FT-IR technique was used to identify the wax precipitation temperature (WPT). The DSC technique was also used in the identification of the onset of the two-phase equilibrium in this work. An additional Model oil made up of C-20 to C-30 hydrocarbons in decane was studied using the DSC experiment. The weight percent solid below the WPT was calculated using the FT-IR experimental results. The WPT and the weight percent solid below the WPT were predicted using an activity coefficient based thermodynamic model. The FT-IR spectroscopy method is found to successfully provide SLE data and also has several advantages over other laboratory-based methods.

  8. Solid/liquid dispersions in drilling and production; Fluides charges en forage et production petroliere

    Peysson, Y. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France)


    To reach the new oil and gas fields, the oil industry is developing more and more sophisticated drilling and production schemes. Wells trajectories are now deviated, horizontal, with high extended reach, multi-branched, ultra deep offshore, etc. Extended reach wells are up to 10 km and offshore drilling is close to 3000 m of water depth. In these cases, drilling and production techniques are pushed to the limits. The operating conditions, the properties of the different materials employed must be controlled and operated in a more accurate way. This is the case for solid/liquid dispersions that are common in these operations: drilling, fluids, cements, hydrates dispersions oil and gas phases, sand venue with reservoir fluids, etc. These mixtures present some specific properties that can be at the limit between solid or liquid behaviour. For particular conditions the solid phase can create structures able to support large stresses and in others circumstances the mixture can flow like a viscous paste. Modeling of these characteristics is not easy and needs to use knowledge of different areas: Theology, physico-chemistry, hydrodynamics. thermodynamics, etc. In this revue, different systems used in the drilling and production industry will be discussed. Main properties of these systems and different development conducted by IFP will be addressed. (authors)

  9. Metastable nanobubbles at the solid-liquid interface due to contact angle hysteresis.

    Nishiyama, Takashi; Yamada, Yutaka; Ikuta, Tatsuya; Takahashi, Koji; Takata, Yasuyuki


    Nanobubbles exist at solid-liquid interfaces between pure water and hydrophobic surfaces with very high stability, lasting in certain cases up to several days. Not only semispherical but also other shapes, such as micropancakes, are known to exist at such interfaces. However, doubt has been raised as to whether or not the nanobubbles are gas-phase entities. In this study, surface nanobubbles at a pure water-highly ordered pyrolytic graphite (HOPG) interface were investigated by peak force quantitative nanomechanics (PF-QNM). Multiple isolated nanobubbles generated by the solvent-exchange method were present on the terraced areas, avoiding the steps of the HOPG surface. Adjacent nanobubbles coalesced and formed metastable nanobubbles. Coalescence was enhanced by the PF-QNM measurement. We determined that nanobubbles can exist for a long time because of nanoscale contact angle hysteresis at the water-HOPG interface. Moreover, the hydrophilic steps of HOPG were avoided during coalescence, providing evidence that the nanobubbles are truly gas phase.

  10. Remediation of PAH contaminated soils: application of a solid-liquid two-phase partitioning bioreactor.

    Rehmann, Lars; Prpich, George P; Daugulis, Andrew J


    The feasibility of a two-step treatment process has been assessed at laboratory scale for the remediation of soil contaminated with a model mixture of polycyclic aromatic hydrocarbons (PAHs) (phenanthrene, pyrene, and fluoranthene). The initial step of the process involved contacting contaminated soil with thermoplastic, polymeric pellets (polyurethane). The ability of three different mobilizing agents (water, surfactant (Biosolve) and isopropyl alcohol) to enhance recovery of PAHs from soil was investigated and the results were compared to the recovery of PAHs from dry soil. The presence of isopropyl alcohol had the greatest impact on PAH recovery with approximately 80% of the original mass of PAHs in the soil being absorbed by the polymer pellets in 48 h. The second stage of the suggested treatment involved regeneration of the PAH loaded polymers via PAH biodegradation, which was carried out in a solid-liquid two-phase partitioning bioreactor. In addition to the PAH containing polymer pellets, the bioreactor contained a microbial consortium that was pre-selected for its ability to degrade the model PAHs and after a 14 d period approximately 78%, 62% and 36% of phenanthrene, pyrene, and fluoranthene, respectively, had been desorbed from the polymer and degraded. The rate of phenanthrene degradation was shown to be limited by mass transfer of phenanthrene from the polymer pellets. In case of pyrene and fluoranthene a combination of mass transfer and biodegradation rate might have been limiting.

  11. A hybrid DEM/CFD approach for solid-liquid flows

    QIU Liu-chao; WU Chuan-yu


    A hybrid scheme coupling the discrete element method (DEM) with the computational fluid dynamics (CFD) is developed to model solid-liquid flows. Instead of solving the pressure Poisson equation, we use the compressible volume-averaged continuity and momentum equations with an isothermal stiff equation of state for the liquid phase in our CFD scheme. The motion of the solid phase is obtained by using the DEM, in which the particle-particle and particle-wall interactions are modelled by using the theoretical contact mechanics. The two phases are coupled through the Newton’s third law of motion. To verify the proposed method, the sedi-mentation of a single spherical particle is simulated in water, and the results are compared with experimental results reported in the literature. In addition, the drafting, kissing, and tumbling (DKT) phenomenon between two particles in a liquid is modelled and rea-sonable results are obtained. Finally, the numerical simulation of the density-driven segregation of a binary particulate suspension in-volving 10 000 particles in a closed container is conducted to show that the presented method is potentially powerful to simulate real particulate flows with large number of moving particles.

  12. Fundamental measure density functional theory study of hard spheres solid-liquid interface

    Warshavsky, Vadim


    Interfacial free energy is an important characteristic of solid-liquid interface as it is one of the crucial parameters in many formula of interface thermodynamics such the nucleation theory. Previously different aspects of crystal-melt interfaces were intensively studied with simulations [1,2,3], but theoretical studies with Density Functional Theories (DFT) are inconclusive [4,5]. In this report the structure of hard spheres fcc crystal-melt interfaces and the anisotropy of the interfacial free energies are studied using the Rosenfeld's Fundamental Measure DFT as such a functional leads to reliable coexistence results not only for the hard sphere system but also for the Lennard-Jones systems [6]. The parameters of interfacial density profile were calculated by a proper minimization procedure. For the equilibrium density profile the interfacial free energies were compared with simulation results. 1. R.L.Davidchak and B.B.Laird, Phys.Rev.Lett., 85, 4751(2000). 2. J.J. Hoyt, M. Asta and A. Karma, Phys.Rev.Lett., 86, 5530 (2001). 3. J.R.Morris and X.Song, J.Chem.Phys., 119, 3920 (2003). 4. W.A.Curtin, Phys.Rev.B, 39, 6775(1989). 5. R.Ohnesorge, H.Lowen, and H.Wagner, Phys.Rev.E, 50, 4801 (1994). 6. V.Warshavsky and X.Song, Phys.Rev.E, 69, 061113 (2004).

  13. Mechanical and thermodynamic properties of surfactant aggregates at the solid-liquid interface.

    Rabinovich, Yakov I; Vakarelski, Ivan U; Brown, Scott C; Singh, Pankaj K; Moudgil, Brij M


    Surfactants are widely used to stabilize colloidal systems in a variety of industrial applications through the formation of self-assembled aggregates at the solid-liquid interface. Previous studies have reported that the control of surfactant-mediated slurry stability can be achieved through the manipulation of surfactant chain length and concentration. However, a fundamental understanding of the mechanical and energetic properties of these aggregates, which may aid in the molecular-level design of these systems, is still lacking. In this study, experimentally measured force/distance curves between an atomic force microscope (AFM) tip and self-assembled surfactant aggregates on mica or silica substrates at concentrations higher than the bulk critical micelle concentration (CMC) were used to determine their mechanical and thermodynamic properties. The experimental curves were fitted to a model which describes the interaction between a hard sphere (tip) and a soft substrate (surfactant structures) based on a modified Hertz theory for the case of a thin elastic layer on a rigid substrate. The calculated mechanical properties were found to be in the same order of magnitude as those reported for rubber-like materials (e.g., polydimethylsiloxane (PDMS)). By integrating the force/distance curves, the energy required for breaking the surface aggregates was also calculated. These values are close to those reported for bulk-micelle formation.

  14. Effect of different technologies and animal manures on solid-liquid separation efficiencies

    Giorgia Cocolo


    Full Text Available Solid-liquid separation is a widely used manure treatment option. However, little information is available to predict separator performance in a specific operating condition. This study investigates the effect on the separation efficiency of animal species (cattle and swine, use of flocculants, and separator construction and operating characteristics (filtration, pressurised filtration, settling and centrifugation. Using data available from published experiments, we evaluated correlations of the separation efficiencies with the physical and chemical characteristics of the inlet slurries (dry matter, total nitrogen, ammoniacal nitrogen, phosphorus and potassium. Dry matter concentration of the input manure was found to be the best parameter used to calculate and validate regression equations. Regres sions for the operating conditions of 7 of the 14 subgroups evaluated were significant (P<0.05 for at least one parameter. Pressurised filtration seems to be the process best represented by these regressions that can predict dry matter and nitrogen efficiency with relative root mean squared errors of less than 50%. However, they could only be used for some of the parameters and separation techniques. Therefore, it was not possible to use the available experimental data to define and validate empirical predictive models for all the conditions. Specific studies are needed to define more precise and physically-based models.

  15. Solid Liquid Interdiffusion Bonding of Zn4Sb3 Thermoelectric Material with Cu Electrode

    Lin, Y. C.; Lee, K. T.; Hwang, J. D.; Chu, H. S.; Hsu, C. C.; Chen, S. C.; Chuang, T. H.


    The ZnSb intermetallic compound may have thermoelectric applications because it is low in cost and environmentally friendly. In this study, a Zn4Sb3 thermoelectric element coated with a Ni barrier layer and a Ag reaction layer was bonded with a Ag-coated Cu electrode using a Ag/Sn/Ag solid-liquid interdiffusion bonding process. The results indicated that a Ni5Zn21 intermetallic phase formed easily at the Zn4Sb3/Ni interface, leading to sound adhesion. In addition, Sn film was found to react completely with the Ag layer to form a Ag3Sn intermetallic layer having a melting point of 480°C. The resulting Zn4Sb3 thermoelectric module can be applied at the optimized operation temperature (400°C) of Zn4Sb3 material as a thermoelectric element. The bonding strengths ranged from 14.9 MPa to 25.0 MPa, and shear tests revealed that the Zn4Sb3/Cu-joints fractured through the interior of the thermoelectric elements.

  16. Adsorption of hydrophobin/β-casein mixtures at the solid-liquid interface.

    Tucker, I M; Petkov, J T; Penfold, J; Thomas, R K; Cox, A R; Hedges, N


    The adsorption behaviour of mixtures of the proteins β-casein and hydrophobin at the hydrophilic solid-liquid surface have been studied by neutron reflectivity. The results of measurements from sequential adsorption and co-adsorption from solution are contrasted. The adsorption properties of protein mixtures are important for a wide range of applications. Because of competing factors the adsorption behaviour of protein mixtures at interfaces is often difficult to predict. This is particularly true for mixtures containing hydrophobin as hydrophobin possesses some unusual surface properties. At β-casein concentrations ⩾0.1wt% β-casein largely displaces a pre-adsorbed layer of hydrophobin at the interface, similar to that observed in hydrophobin-surfactant mixtures. In the composition and concentration range studied here for the co-adsorption of β-casein-hydrophobin mixtures the adsorption is dominated by the β-casein adsorption. The results provide an important insight into how the competitive adsorption in protein mixtures of hydrophobin and β-casein can impact upon the modification of solid surface properties and the potential for a wide range of colloid stabilisation applications.

  17. Influence of solid-liquid interactions on dynamic wetting: a molecular dynamics study

    Bertrand, Emilie; Blake, Terence D.; De Coninck, Joël


    Large-scale molecular dynamics (MD) simulations of liquid drops spreading on a solid substrate have been carried out for a very wide range of solid-liquid interactions and equilibrium contact angles. The results for these systems are shown to be consistent with the molecular-kinetic theory (MKT) of dynamic wetting, which emphasizes the role of contact-line friction as the principal channel of energy dissipation. Several predictions have been confirmed. These include a quantitative link between the dynamics of wetting and the work of adhesion and the existence of an optimum equilibrium contact angle that maximizes the speed of wetting. A feature of the new work is that key parameters (κ0 and λ), normally accessible only by fitting the MKT to dynamic contact angle data, are also obtained directly from the simulations, with good agreement between the two sources. This validates the MKT at some fundamental level. Further verification is provided by contact angle relaxation studies, which also lend support to the interfacial tension relaxation process invoked in Shikhmurzaev's hydrodynamic model of dynamic wetting.

  18. Thermodynamic Perturbation Theory for Solid-Liquid Phase Transition of Lennard-Jones Model

    ZHOUShi-Qi; ZHANGXiao-Qi


    Both a free volume approach for Helmholtz free energy and a theoretically-based fitted formula for radial distribution function (rdf) of hard sphere solid are employed to describe the Helmholtz free energy of Lennard-Jones solid in the framework of the first order thermodynamic perturbation theory, which also is employed for the uniform Lennard Jones fluid. The dividing of the Lennard-Jones potential follows from the INCA prescription, but the specification of the equivalent hard sphere diameter is determined by a simple iteration procedure devised originally for liquid state, but extended to solid state in the present study. Two hundred shells are used in the rdf to get an accurate perturbation term.The present approach is very accurate for the description of excess Helmholtz free energy of LJ solid, but shows some deviation from the simulation for excess Helmholtz free energy of uniform LJ fluid when the reduced temperature kT/ε is higher then 5. The present approach is satisfactory for description of solid-liquid phase transition of the Lennard-Jones model.

  19. Thermodynamic Perturbation Theory for Solid-Liquid Phase Transition of Lennard-Jones Model

    ZHOU Shi-Qi; ZHANG Xiao-Qi


    Both a free volume approach for Helmholtz free energy and a theoretically-based fitted formula for radial distribution function (rdf) of hard sphere solid are employed to describe the Helmholtz free energy of Lennard-Jones solid in the framework of the first order thermodynamic perturbation theory, which also is employed for the uniform LennardJones fluid. The dividing of the Lennard-Jones potential follows from the WCA prescription, but the specification of the equivalent hard sphere diameter is determined by a simple iteration procedure devised originally for liquid state, but extended to solid state in the present study. Two hundred sheiks are used in the rdf to get an accurate perturbation term.The present approach is very accurate for the description of excess Helmholtz free energy of LJ solid, but shows some deviation from the simulation for excess Helmholtz free energy of uniform LJ fluid when the reduced temperature kT/ε is higher then 5. The present approach is satisfactory for description of solid-liquid phase transition of the Lennard-Jones model.

  20. Step free energies at faceted solid-liquid interfaces from equilibrium molecular dynamics simulations.

    Frolov, T; Asta, M


    In this work a method is proposed for computing step free energies for faceted solid-liquid interfaces based on atomistic simulations. The method is demonstrated in an application to (111) interfaces in elemental Si, modeled with the classical Stillinger-Weber potential. The approach makes use of an adiabatic trapping procedure, and involves simulations of systems with coexisting solid and liquid phases separated by faceted interfaces containing islands with different sizes, for which the corresponding equilibrium temperatures are computed. We demonstrate that the calculated coexistence temperature is strongly affected by the geometry of the interface. We find that island radius is inversely proportional to superheating, allowing us to compute the step free energy by fitting simulation data within the formalism of classical nucleation theory. The step free energy value is computed to be γ(st) = 0.103 ± 0.005 × 10(-10) J/m. The approach outlined in this work paves the way to the calculation of step free energies relevant to the solidification of faceted crystals from liquid mixtures, as encountered in nanowire growth by the vapor-liquid-solid mechanism and in alloy casting. The present work also shows that at low undercoolings the Stillinger-Weber interatomic potential for Si tends to crystallize in the wurtzite, rather than the diamond-cubic structure.

  1. Solid-liquid interface free energies of pure bcc metals and B2 phases.

    Wilson, S R; Gunawardana, K G S H; Mendelev, M I


    The solid-liquid interface (SLI) free energy was determined from molecular dynamics (MD) simulation for several body centered cubic (bcc) metals and B2 metallic compounds (space group: Pm3̄m; prototype: CsCl). In order to include a bcc metal with a low melting temperature in our study, a semi-empirical potential was developed for Na. Two additional synthetic "Na" potentials were also developed to explore the effect of liquid structure and latent heat on the SLI free energy. The obtained MD data were compared with the empirical Turnbull, Laird, and Ewing relations. All three relations are found to predict the general trend observed in the MD data for bcc metals obtained within the present study. However, only the Laird and Ewing relations are able to predict the trend obtained within the sequence of "Na" potentials. The Laird relation provides the best prediction for our MD data and other MD data for bcc metals taken from the literature. Overall, the Laird relation also agrees well with our B2 data but requires a proportionality constant that is substantially different from the bcc case. It also fails to explain a considerable difference between the SLI free energies of some B2 phases which have nearly the same melting temperature. In contrast, this difference is satisfactorily described by the Ewing relation. Moreover, the Ewing relation obtained from the bcc dataset also provides a reasonable description of the B2 data.


    TANG Xuelin; QIAN Zhongdong; WU Yulin


    The dense solid-phase governing equations for two-phase flows are obtained by using the kinetic theory of gas molecules. Assuming that the solid-phase velocity distributions obey the Maxwell equations, the collision term for particles under dense two-phase flow conditions is also derived.In comparison with the governing equations of a dilute two-phase flow, the solid-particle's governing equations are developed for a dense turbulent solid-liquid flow by adopting some relevant terms from the dilute two-phase governing equations. Based on Cauchy-Helmholtz theorem and Smagorinsky model,a second-order dynamic sub-grid-scale (SGS) model, in which the sub-grid-scale stress is a function of both the strain-rate tensor and the rotation-rate tensor, is proposed to model the two-phase governing equations by applying dimension analyses. Applying the SIMPLEC algorithm and staggering grid system to the two-phase discretized governing equations and employing the slip boundary conditions on the walls, the velocity and pressure fields, and the volumetric concentration are calculated. The simulation results are in a fairly good agreement with experimental data in two operating cases in a conduit with a rectangular cross-section and these comparisons imply that these models are practical.

  3. Determination of solid-liquid interfacial energies in the In-Bi-Sn ternary alloy

    Akbulut, S; Ocak, Y [Department of Physics, Institute of Science and Technology, Erciyes University, Kayseri, 38039 (Turkey); Marasli, N; Keslioglu, K [Department of Physics, Faculty of Arts and Sciences, Erciyes University, Kayseri, 38039 (Turkey); Kaya, H [Department of Science Education, Education Faculty, Erciyes University, Kayseri, 38039 (Turkey); Cadirli, E [Department of Physics, Faculty of Arts and Sciences, Nigde University, Nigde (Turkey)], E-mail:


    The equilibrated grain boundary groove shapes of solid In{sub 2}Bi solution in equilibrium with the In-Bi-Sn eutectic liquid were observed from a quenched sample at 59 {sup 0}C. The Gibbs-Thomson coefficient, solid-liquid interfacial energy and grain boundary energy of the solid In{sub 2}Bi solution have been determined to be (1.42 {+-} 0.07) x 10{sup -7} K m, (49.6 {+-} 5.0) x 10{sup -3} J m{sup -2} and (97.1 {+-} 10.7) x 10{sup -3} J m{sup -2}, respectively, from the observed grain boundary groove shapes. The thermal conductivities of the solid phases for In-21.23 at% Bi-19.04 at% Sn and In-30.5 at% Bi-3 at% Sn alloys and the thermal conductivity ratio of the liquid phase to the solid phase for In-21.23 at% Bi-19.04 at% Sn have also been measured with a radial heat flow apparatus and a Bridgman type growth apparatus, respectively, at their melting temperature.

  4. Impact of membrane solid-liquid separation on design of biological nutrient removal activated sludge systems.

    Ramphao, M; Wentzel, M C; Merritt, R; Ekama, G A; Young, T; Buckley, C A


    Installing membranes for solid-liquid separation into biological nutrient removal (BNR) activated sludge (AS) systems makes a profound difference not only in the design of the BNR system itself, but also in the design approach for the whole wastewater treatment plant (WWTP). In multizone BNR systems with membranes in the aerobic reactor and fixed volumes for the anaerobic, anoxic, and aerobic zones (i.e., fixed volume fractions), the mass fractions can be controlled (within a range) with the interreactor recycle ratios. This zone mass fraction flexibility is a significant advantage in membrane BNR systems over conventional BNR systems with SSTs, because it allows for changing of the mass fractions to optimize biological N and P removal in conformity with influent wastewater characteristics and the effluent N and P concentrations required. For PWWF/ADWF ratios in the upper range (f(q) approximately 2.0), aerobic mass fractions in the lower range (f(maer) secondary settling tanks is not as large (40% to 60%), the cost of the membranes can be offset against sludge thickening and stabilization costs. Moving from a flow-unbalanced raw wastewater system to a flow-balanced (f(q) = 1), low (usually settled) wastewater strength system can double the ADWF capacity of the biological reactor, but the design approach of the WWTP changes from extended aeration to include primary sludge stabilization. The cost of primary sludge treatment then has to be paid from the savings from the increased WWTP capacity.

  5. The solid-liquid phase diagrams of binary mixtures of consecutive, even saturated fatty acids.

    Costa, Mariana C; Sardo, Mariana; Rolemberg, Marlus P; Coutinho, João A P; Meirelles, Antonio J A; Ribeiro-Claro, Paulo; Krähenbühl, M A


    For the first time, the solid-liquid phase diagrams of five binary mixtures of saturated fatty acids are here presented. These mixtures are formed of caprylic acid (C(8:0))+capric acid (C(10:0)), capric acid (C(10:0))+lauric acid (C(12:0)), lauric acid (C(12:0))+myristic acid (C(14:0)), myristic acid (C(14:0))+palmitic acid (C(16:0)) and palmitic acid (C(16:0))+stearic acid (C(18:0)). The information used in these phase diagrams was obtained by differential scanning calorimetry (DSC), X-ray diffraction (XRD), FT-Raman spectrometry and polarized light microscopy, aiming at a complete understanding of the phase diagrams of the fatty acid mixtures. All of the phase diagrams reported here presented the same global behavior and it was shown that this was far more complex than previously imagined. They presented not only peritectic and eutectic reactions, but also metatectic reactions, due to solid-solid phase transitions common in fatty acids and regions of solid solution not previously reported. This work contributes to the elucidation of the phase behavior of these important biochemical molecules, with implications in various industrial applications.

  6. Extraction and Analysis of Display Data

    Land, Chris; Moye, Kathryn


    The Display Audit Suite is an integrated package of software tools that partly automates the detection of Portable Computer System (PCS) Display errors. [PCS is a lap top computer used onboard the International Space Station (ISS).] The need for automation stems from the large quantity of PCS displays (6,000+, with 1,000,000+ lines of command and telemetry data). The Display Audit Suite includes data-extraction tools, automatic error detection tools, and database tools for generating analysis spread sheets. These spread sheets allow engineers to more easily identify many different kinds of possible errors. The Suite supports over 40 independent analyses, 16 NASA Tech Briefs, November 2008 and complements formal testing by being comprehensive (all displays can be checked) and by revealing errors that are difficult to detect via test. In addition, the Suite can be run early in the development cycle to find and correct errors in advance of testing.

  7. Web Template Extraction Based on Hyperlink Analysis

    Julián Alarte


    Full Text Available Web templates are one of the main development resources for website engineers. Templates allow them to increase productivity by plugin content into already formatted and prepared pagelets. For the final user templates are also useful, because they provide uniformity and a common look and feel for all webpages. However, from the point of view of crawlers and indexers, templates are an important problem, because templates usually contain irrelevant information such as advertisements, menus, and banners. Processing and storing this information is likely to lead to a waste of resources (storage space, bandwidth, etc.. It has been measured that templates represent between 40% and 50% of data on the Web. Therefore, identifying templates is essential for indexing tasks. In this work we propose a novel method for automatic template extraction that is based on similarity analysis between the DOM trees of a collection of webpages that are detected using menus information. Our implementation and experiments demonstrate the usefulness of the technique.

  8. Optimization for ultrasound-assisted extraction of polysaccharides with chemical composition and antioxidant activity from the Artemisia sphaerocephala Krasch seeds.

    Zheng, Quan; Ren, Daoyuan; Yang, Nana; Yang, Xingbin


    Artemisia sphaerocephala Krasch seeds polysaccharides have been reported to have a variety of important biological activities. However, effective extraction of Artemisia sphaerocephala Krasch seeds polysaccharides is still an unsolved issue. In this study, the orthogonal rotatable central composite design was employed to optimize ultrasound-assisted extraction conditions of Artemisia sphaerocephala Krasch seeds polysaccharides. Based on a single-factor analysis method, ultrasonic power, extraction time, solid-liquid ratio and extraction temperature were shown to significantly affect the yield of polysaccharides extracted from the A. sphaerocephala Krasch seeds. The optimal conditions for extraction of Artemisia sphaerocephala Krasch seeds polysaccharides were determined as following: ultrasonic power 243W, extraction time 125min, solid-liquid ratio 64:1 and extraction temperature 64°C, where the experimental yield was 14.78%, which was well matched with the predicted value of 14.81%. Furthermore, ASKP was identified as a typical heteropolysaccharide with d-galacturonic acid (38.8%) d-galactose (20.2%) and d-xylose (15.5%) being the main constitutive monosaccharides. Moreover, Artemisia sphaerocephala Krasch seeds polysaccharides exhibited high total reducing power and considerable scavenging activities on DPPH, hydroxyl and superoxide radicals, in a concentration-dependent manner in vitro.

  9. Pilot study of a fluidized-pellet-bed technique for simultaneous solid/liquid separation and sludge thickening in a sewage treatment plant

    Wang, X.C.; Jin, P.K.; Yuan, H.L.; Wan, E.R.; Tambo, N.


    A fluidized-pellet-bed separator with movable sludge hoppers was applied in pilot scale for the separation and thickening of activated sludge mixture liquid. Under the condition of suspension SS around 4000 mg/L, polymer (CJX103, cationic, MW 5x10{sup 6}) dose at a dry solid ratio of 0.003 and upward flow rate at 5.4 m/hr, the fluidized pellet bed performed solid/liquid separation and sludge thickening well. The SS concentration of the treated water was about 5 mg/L on average and the moisture content of the sludge after screening for 5 mm was less than 94% which is much lower than that after conventional settling and thickening and easy to be finally disposed. At higher upward flow rate of 7.2 m/hr. similar result could also be obtained but higher polymer dose (solid ratio of 0.004) was required. The morphological characteristics and density-size relationship of the granular particles formed in the fluidized pellet bed were also investigated by image analysis and settling velocity measurement of individual particles. The two-dimensional fractal dimension was evaluated to be 1.6-1.8, showing a good quasi-spherical morphology of the granular particles with their density much higher than the conventional flocs. The results of the pilot study indicate a possible way to innovate the conventional secondary settling and gravitational thickening processes for solid/liquid separation and sludge handling, especially for small scale wastewater treatment plants to reach the goal of space saving and higher treatment efficiency. (author)

  10. Modeling and optimization of ultrasound-assisted extraction of polysaccharide from Cucurbita moschata.

    Prakash Maran, J; Mekala, V; Manikandan, S


    Polysaccharides from pumpkin were extracted by ultrasound-assisted extraction technology using four factors at five levels central composite rotatable response surface design (CCRD). On using single factor analysis, process variables such as extraction temperature (50-70 °C), power of ultrasound (50-70 W), time (15-25 min) and solid-liquid ratio (1:10-1:20 g/ml) were selected. Experiments were conducted to evaluate the effects of four independent variables on the maximum extraction yield of polysaccharides. From the experimental data, second order polynomial mathematical model were developed with high coefficient of determination values (R(2)>0.96). From response surface plots, temperature and ultrasound power exhibited independent and interactive effects on the extraction yields. Extraction temperature of 70 °C, ultrasound power of 70 W, time of 23 min and solid-liquid ratio of 1:10 g/ml were determined as optimal conditions with a maximum polysaccharides yield of 16.21%, which was confirmed through the validation of the experiments.

  11. Prediction of Solid-Liquid Equilibrium for KCl in Mixed Water-Ethanol Solutions Using the LIQUAC Model

    LIN Yangzheng; LI Jiding; ZENG Chuyi; CHEN Cuixian


    The LIQUAC model is often used to predict vapor-liquid equilibria, osmotic coefficients, and mean ion activity coefficients for electrolyte systems. This paper describes a thermodynamic method to analyze solid-liquid equilibrium for electrolytes in mixed solvents solutions using the LIQUAC model. The KCl solubilities in mixed water-ethanol solutions are predicted with the LIQUAC model and its original interaction parameters. This method is also used to obtain new K+-ethanol interaction parameters in the LIQUAC model from the solubility data. The new interaction parameters accurately predict the vapor-liquid equilibrium data of K+ salts (including KCl, KBr, and KCOOCH3) in mixed water-ethanol solutions. The results illustrate the flexibility of the LIQUAC model which can predict not only vapor-liquid equilibrium but also solid-liquid equilibrium in mixed solvent systems.

  12. In-drop capillary spooling of spider capture thread inspires hybrid fibers with mixed solid-liquid mechanical properties

    Elettro, Hervé; Neukirch, Sébastien; Vollrath, Fritz; Antkowiak, Arnaud


    An essential element in the web-trap architecture, the capture silk spun by ecribellate orb spiders consists of glue droplets sitting astride a silk filament. Mechanically this thread presents a mixed solid-liquid behavior unknown to date. Under extension, capture silk behaves as a particularly stretchy solid, owing to its molecular nanosprings, but it totally switches behavior in compression to now become liquid-like: It shrinks with no apparent limit while exerting a constant tension. Here, we unravel the physics underpinning the unique behavior of this ”liquid wire” and demonstrate that its mechanical response originates in the shape-switching of the silk filament induced by buckling within the droplets. Learning from this natural example of geometry and mechanics, we manufactured programmable liquid wires that present previously unidentified pathways for the design of new hybrid solid-liquid materials.

  13. Optimizing the extraction of antibacterial compounds from pineapple leaf fiber

    Zhuang Zhikai


    Full Text Available Five different solvents (petroleum ether, chloroform, ethyl acetate, acetone, and distilled water were used to extract antibacterial compounds from pineapple leaf fiber. Compounds extracted using acetone showed the greatest antibacterial effect against Escherichia coli, measured by inhibition zone diameter. Three extraction parameters including temperature, time and solid-liquid ratio were optimized through orthogonal experiment based on single factor investigations for achieving maximum active substance extraction rate and bacteriostatic effect. Results showed that using acetone, the optimum extraction conditions for temperature, time and solid-liquid ratio were 45°C, 8 h, and 1:40 (g/ml, respectively.

  14. Response surface optimization of ultrasound assisted extraction of pectin from pomegranate peel.

    Moorthy, I Ganesh; Maran, J Prakash; Surya, S Muneeswari; Naganyashree, S; Shivamathi, C S


    Ultrasound assisted extraction of pectin from waste pomegranate peel was investigated and optimized using Box-Behnken response surface design coupled with numerical optimization technique. The individual and interactive effect of process variables (solid-liquid ratio, pH, extraction time and temperature) on the pectin yield was studied. The experimental data obtained were analyzed by Pareto analysis of variance (ANOVA) and second-order polynomial models were developed using multiple regression analysis. The models developed from the experimental design were predictive and good fit with the experimental data with high coefficient of determination (R(2)) value. The optimal extraction condition was found to be 1:17.52 g/ml of solid-liquid ratio, 1.27 of pH, 28.31 min of extraction time and 61.90 °C of extraction temperature respectively. Under the optimal conditions, experimental yield was very close to the predicted values. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Statistical optimization of process parameters influencing the biotransformation of plant tannin into gallic acid under solid-liquid fermentation

    Bibhu Prasad Panda; Rupa Mazumder; Rintu Banerjee


    Purpose : To optimize and produce gallic acid by biotransformation of plant tannin under solid-liquid fermentation. Materials and Methods : Optimization of different process parameters like temperature, relative humidity, pH of the liquid medium, fermentation period, volume of inoculum weight of substrate influencing gallic acid production from plant tannin were carried out by EVOP factorial method. Results : Maximum gallic acid yield of 93.29% was produced at 28ΊC, 70% relative humidity, pH ...

  16. Stirring-controlled solidified floating solid-liquid drop microextraction as a new solid phase-enhanced liquid-phase microextraction method by exploiting magnetic carbon nanotube-nickel hybrid.

    Ghazaghi, Mehri; Mousavi, Hassan Zavvar; Shirkhanloo, Hamid; Rashidi, Alimorad


    A specific technique is introduced to overcome limitations of classical solidification of floating organic drop microextraction, such as tedious and time-consuming centrifuge step and using disperser solvent, by facile and efficient participation of solid and liquid phases. In this proposed method of stirring-controlled solidified floating solid-liquid drop microextraction (SC-SF-SLDME), magnetic carbon nanotube-nickel hybrid (MNi-CNT) as a solid part of the extractors are dispersed ultrasonically in sample solution, and the procedure followed by dispersion of liquid phase (1-undecanol) through high-rate stirring and easily recollection of MNi-CNT in organic solvent droplets through hydrophobic force. With the reduction in speed of stirring, one solid-liquid drop is formed on top of the solution. MNi-CNT acts as both extractor and the coalescence helper between organic droplets for a facile recollection. MNi-CNT was prepared by spray pyrolysis of nickel oleate/toluene mixture at 1000 °C. Four tyrosine kinase inhibitors were selected as model analytes and the effecting parameters were investigated. The results confirmed that magnetic nanoadsorbent has an important role in the procedure and complete collection of dispersed solvent is not achieved in the absence of the solid phase. Also, short extraction time exhibited success of the proposed method and effect of dispersed solid/liquid phases. The limits of quantification (LOQs) for imatinib, sunitinib, erlotinib, and nilotinib were determined to be as low as 0.7, 1.7, 0.6, and 1.0 μg L(-1), respectively. The intra-day precisions (RSDs) were lower than 4.5%. Method performance was investigated by determination of mentioned tyrosine kinase inhibitors (TKIs) in human serum and cerebrospinal fluid samples with good recoveries in the range of 93-98%.

  17. Ultrasound assisted citric acid mediated pectin extraction from industrial waste of Musa balbisiana.

    Maran, J Prakash; Priya, B; Al-Dhabi, Naif Abdullah; Ponmurugan, K; Moorthy, I Ganesh; Sivarajasekar, N


    The objectives of the present work are to extract pectin from industrial waste of Musa balbisiana by ultrasound assisted citric acid mediated extraction method and optimization was done through central composite statistical experimental design under response surface methodology. The outcomes of this study exhibited that, process variables (ultrasound power, pH and extraction time) had considerable influence on the pectin extraction. Second order mathematical equation was constructed to predict the data through regression analysis. The optimal extraction process condition was ultrasound power of 323w, pH of 3.2, extraction time of 27min and SL (solid-liquid) ratio of 1:15g/ml. The mean experimental yield of pectin (8.99±0.018%) was fine accord among predicted yield of pectin (9.02%). Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Antibiogram and GC analysis of Euphorbia hirta leaf extract


    The antibiogram activity of ethanolic and aqueous extract of E.hirta was studied. Ethanol extract of the plant showed the maximal antibacterial activity and G.C Analysis showed the presence of citronellal. The extract showed inhibited the growth of E.coli, S.aureus, P.aeruginosa, Proteus etc.,

  19. Real Time Characterization of Solid/Liquid Interfaces During Directional Solidification

    Sen, S.; Kaukler, W. K.; Curreri, P. A.; Peters, P.


    A X-Ray Transmission Microscope (XTM) has been developed to observe in real time and in-situ solidification phenomenon at the solid/liquid interface. Recent improvements in the horizontal Bridgman furnace design provides real-time magnification (during solidification) up to 12OX. The increased magnification has enabled for the first time the XTM imaging of real-time growth of fibers and particles with diameters of 3-6 micrometers. Further, morphological transitions from planar to cellular interfaces have also been imaged. Results from recent XTM studies on Al-Bi monotectic system, Al-Au eutectic system and interaction of insoluble particles with s/I interfaces in composite materials will be presented. An important parameter during directional solidification of molten metal is the interfacial undercooling. This parameter controls the morphology and composition at the s/I interface. Conventional probes such as thermocouples, due to their large bead size, do not have sufficient resolution for measuring undercooling at the s/I interface. Further, the intrusive nature of the thermocouples also distorts the thermal field at the s/I interface. To overcome these inherent problems we have recently developed a compact furnace which utilizes a non-intrusive technique (Seebeck) to measure undercooling at the S/I interface. Recent interfacial undercooling measurements obtained for the Pb-Sn system will be presented. The Seebeck measurement furnace in the future will be integrated with the XTM to provide the most comprehensive tool for real time characterization of s/I interfaces during solidification.

  20. Performance Validation and Scaling of a Capillary Membrane Solid-Liquid Separation System

    Rogers, S; Cook, J; Juratovac, J; Goodwillie, J; Burke, T


    Algaeventure Systems (AVS) has previously demonstrated an innovative technology for dewatering algae slurries that dramatically reduces energy consumption by utilizing surface physics and capillary action. Funded by a $6M ARPA-E award, transforming the original Harvesting, Dewatering and Drying (HDD) prototype machine into a commercially viable technology has required significant attention to material performance, integration of sensors and control systems, and especially addressing scaling issues that would allow processing extreme volumes of algal cultivation media/slurry. Decoupling the harvesting, dewatering and drying processes, and addressing the rate limiting steps for each of the individual steps has allowed for the development individual technologies that may be tailored to the specific needs of various cultivation systems. The primary performance metric used by AVS to assess the economic viability of its Solid-Liquid Separation (SLS) dewatering technology is algae mass production rate as a function of power consumption (cost), cake solids/moisture content, and solids capture efficiency. An associated secondary performance metric is algae mass loading rate which is dependent on hydraulic loading rate, area-specific hydraulic processing capacity (gpm/in2), filter:capillary belt contact area, and influent algae concentration. The system is capable of dewatering 4 g/L (0.4%) algae streams to solids concentrations up to 30% with capture efficiencies of 80+%, however mass production is highly dependent on average cell size (which determines filter mesh size and percent open area). This paper will present data detailing the scaling efforts to date. Characterization and performance data for novel membranes, as well as optimization of off-the-shelf filter materials will be examined. Third party validation from Ohio University on performance and operating cost, as well as design modification suggestions will be discussed. Extrapolation of current productivities

  1. Preparation of the initial solid liquid interface and melt in directional solidification

    Nguyen Thi, H.; Drevet, B.; Debierre, J. M.; Camel, D.; Dabo, Y.; Billia, B.


    The preparation of the initial conditions (solid-liquid interface morphology and solute segregation in the liquid phase) on which growth is started is a very critical step in directional-solidification experiments. Dedicated experiments on Al-1.5 wt% Ni consisting in directional melting followed by thermal stabilisation with different lengths, show that precise control is in practice not straightforward. Indeed, in the mushy zone created by melting the original solid sample, temperature gradient zone melting (TGZM) causes migration of solute-rich liquid droplets and channels. A model is proposed to describe this process and validate the physical interpretation of the experiments through numerical simulation. Knowing the status of the preparation, the intriguing observations in the partially melted region of the Al-1.5 wt% Ni alloys solidified in the Advanced Gradient Heating Facility of European Space Agency during the LMS and STS-95 space missions can now be explained. Finally, the influence of initial interface morphology and melt segregation on directional-solidification transient is discussed, based on a comparison of Al-Ni alloys with hypoeutectic Al-Li alloys previously grown on Earth and in space. It follows that for experiments achieved on original rods with equiaxed microstructure, the efficiency of the preparatory melting and stabilisation phases can be evaluated from the solute macrosegregation profile in the region in between the non-melted solid and directional solidification. The major conclusion is that when the melt is mixed by fluid flow, the initial conditions are near to their asymptotic state at the end of TGZM whereas, when solute diffusion is the mode of transport into the bulk liquid, the condition of homogeneous melt becomes limiting and too much time-consuming to be fulfilled, which in particular holds for the 3D-experiments carried out in the reduced-gravity environment of space.

  2. Digestion of frozen/thawed food waste in the hybrid anaerobic solid-liquid system.

    Stabnikova, O; Liu, X Y; Wang, J Y


    The hybrid anaerobic solid-liquid (HASL) system, which is a modified two-phase anaerobic digester, is to be used in an industrial scale operation to minimize disposal of food waste at incineration plants in Singapore. The aim of the present research was to evaluate freezing/thawing of food waste as a pre-treatment for its anaerobic digestion in the HASL system. The hydrolytic and fermentation processes in the acidogenic reactor were enhanced when food waste was frozen for 24h at -20 degrees C and then thawed for 12h at 25 degrees C (experiment) in comparison with fresh food waste (control). The highest dissolved COD concentrations in the leachate from the acidogenic reactors were 16.9 g/l on day 3 in the control and 18.9 g/l on day 1 in the experiment. The highest VFA concentrations in the leachate from the acidogenic reactors were 11.7 g/l on day 3 in the control and 17.0 g/l on day 1 in the experiment. The same volume of methane was produced during 12 days in the control and 7 days in the experiment. It gave the opportunity to diminish operational time of batch process by 42%. The effect of freezing/thawing of food waste as pre-treatment for its anaerobic digestion in the HASL system was comparable with that of thermal pre-treatment of food waste at 150 degrees C for 1h. However, estimation of energy required either to heat the suspended food waste to 150 degrees C or to freeze the same quantity of food waste to -20 degrees C showed that freezing pre-treatment consumes about 3 times less energy than thermal pre-treatment.

  3. Molecular simulation of fluid mixtures in bulk and at solid-liquid interfaces

    Kern, Jesse L.

    The properties of a diverse range of mixture systems at interfaces are investigated using a variety of computational techniques. Molecular simulation is used to examine the thermodynamic, structural, and transport properties of heterogeneous systems of theoretical and practical importance. The study of binary hard-sphere mixtures at a hard wall demonstrates the high accuracy of recently developed classical-density functionals. The study of aluminum--gallium solid--liquid heterogeneous interfaces predicts a significant amount of prefreezing of the liquid by adopting the structure of the solid surface. The study of ethylene-expanded methanol within model silica mesopores shows the effect of confinement and surface functionalzation on the mixture composition and transport inside of the pores. From our molecular-dynamics study of binary hard-sphere fluid mixtures at a hard wall, we obtained high-precision calculations of the wall-fluid interfacial free energies, gamma. We have considered mixtures of varying diameter ratio, alpha = 0.7,0.8,0.9; mole fraction, x 1 = 0.25,0.50,0.75; and packing fraction, eta compressive stress on the Ga atoms. Bulk methanol--ethylene mixtures under vapor-liquid equilibrium conditions have been characterized using Monte Carlo and molecular dynamics. The simulated vapor-liquid coexistence curves for the pure-component and binary mixtures agree well with experiment, as do the mixture volumetric expansion results. Using chemical potentials obtained from the bulk simulations, the filling of a number of model silica mesopores with ethylene and methanol is simulated. We report the compositions of the confined fluid mixtures over a range of pressures and for three degrees of nominal pore hydrophobicity.

  4. Anisotropy and roughness of the solid-liquid interface of BCC Fe.

    Sun, Yongli; Wu, Yongquan; Lu, Xiuming; Li, Rong; Xiao, Junjiang


    Melting point T m and kinetic coefficient μ (a proportional constant between the interfacial velocity ν and undercooling ΔT), along with the structural roughness of the solid-liquid interface for body centered cubic (BCC) Fe were calculated by molecular dynamics (MD) simulation. All simulations applied the Sutton-Chen potential, and adopted average bond orientational order (ABOO) parameters together with Voronoi polyhedron method to characterize atomic structure and calculate atomic volume. Anisotropy of T m was found through about 20~40 K decreasing from [100] to [110] and continuously to [111]. Anisotropy of μ with three low index orientations was found as: μ s,[100] > > μ s,[110] > μ s,[111] for solidifying process and μ m,[100] > > μ m,[111] > μ m,[110] for melting process. Slight asymmetry between melting and solidifying was discovered from that the ratios of μ m/μ s are all slightly larger than 1. To explain these, interfacial roughness R int and area ratio S/S 0 (ratio of realistic interfacial area S and the ideal flat cross-sectional area S 0) were defined to verify the anisotropy of interfacial roughness under different supercoolings/superheatings. The results indicated interfacial roughness anisotropies were approximately [100] > [111] > [110]; the interface in melting process is rougher than that in solidifying process; asymmetry of interfacial roughness was larger when temperature deviation ΔT was larger. Anisotropy and asymmetry of interfacial roughness fitted the case of kinetic coefficient μ very well, which could give some explanations to the anisotropies of T m and μ.

  5. Universality and criticality of a second-order granular solid-liquid-like phase transition.

    Castillo, Gustavo; Mujica, Nicolás; Soto, Rodrigo


    We experimentally study the critical properties of the nonequilibrium solid-liquid-like transition that takes place in vibrated granular matter. The critical dynamics is characterized by the coupling of the density field with the bond-orientational order parameter Q(4), which measures the degree of local crystallization. Two setups are compared, which present the transition at different critical accelerations as a result of modifying the energy dissipation parameters. In both setups five independent critical exponents are measured, associated to different properties of Q(4): the correlation length, relaxation time, vanishing wavenumber limit (static susceptibility), the hydrodynamic regime of the pair correlation function, and the amplitude of the order parameter. The respective critical exponents agree in both setups and are given by ν(⊥)=1,ν(∥)=2,γ=1,η≈0.6-0.67, and β=1/2, whereas the dynamical critical exponent is z=ν(∥)/ν(⊥)=2. The agreement on five exponents is an exigent test for the universality of the transition. Thus, while dissipation is strictly necessary to form the crystal, the path the system undergoes toward the phase separation is part of a well-defined universality class. In fact, the local order shows critical properties while density does not. Being the later conserved, the appropriate model that couples both is model C in the Hohenberg and Halperin classification. The measured exponents are in accord with the nonequilibrium extension to model C if we assume that α, the exponent associated in equilibrium to the specific heat divergence but with no counterpart in this nonequilibrium experiment, vanishes.

  6. A comparison of BNR activated sludge systems with membrane and settling tank solid-liquid separation.

    Ramphao, M C; Wentzel, M C; Ekama, G A; Alexander, W V


    Installing membranes for solid-liquid separation into biological nutrient removal (BNR) activated sludge (AS) systems makes a profound difference not only to the design of the membrane bio-reactor (MBR) BNR system itself, but also to the design approach for the whole wastewater treatment plant (WWTP). In multi-zone BNR systems with membranes in the aerobic reactor and fixed volumes for the anaerobic, anoxic and aerobic zones (i.e. fixed volume fractions), the mass fractions can be controlled (within a range) with the inter-reactor recycle ratios. This zone mass fraction flexibility is a significant advantage of MBR BNR systems over BNR systems with secondary settling tanks (SSTs), because it allows changing the mass fractions to optimise biological N and P removal in conformity with influent wastewater characteristics and the effluent N and P concentrations required. For PWWF/ADWF ratios (fq) in the upper range (fq approximately 2.0), aerobic mass fractions in the lower range (f(maer) settling and long sludge age). However, the volume reduction compared with equivalent BNR systems with SSTs will not be large (40-60%), but the cost of the membranes can be offset against sludge thickening and stabilisation costs. Moving from a flow unbalanced raw wastewater system to a flow balanced (fq = 1) low (usually settled) wastewater strength system can double the ADWF capacity of the biological reactor, but the design approach of the WWTP changes away from extended aeration to include primary sludge stabilisation. The cost of primary sludge treatment then has to be offset against the savings of the increased WWTP capacity.

  7. Thermodynamic analysis of Cr(VI) extraction using TOPO impregnated membranes

    Praveen, Prashant; Loh, Kai-Chee, E-mail:


    Highlights: • Cr(VI) extraction by extractant impregnated membranes (EIM) was investigated. • EIM exhibited high extraction efficiency, mass transfer rate and stability. • Mass transfer mechanism was proposed based on kinetics and equilibrium data. • Uptake of Cr(VI) by EIMs was endothermic and spontaneous. • Cr(VI) extraction by EIMs was dominated by physical interactions. - Abstract: Solid/liquid extraction of Cr(VI) was accomplished using trioctylphosphine oxide impregnated polypropylene hollow fiber membranes. Extraction of 100–500 mg/L Cr(VI) by the extractant impregnated membranes (EIM) was characterized by high uptake rate and capacity, and equilibrium was attained within 45 min of contact. Extraction equilibrium was pH-dependent (at an optimal pH 2), whereas stripping using 0.2 M sodium hydroxide yielded the highest recovery of 98% within 60 min. The distribution coefficient was independent of initial Cr(VI) concentration, and the linear distribution equilibrium isotherm could be modeled using Freundlich isotherm. The mass transfer kinetics of Cr(VI) was examined using pseudo-second-order and intraparticle diffusion models and a mass transfer mechanism was deduced. The distribution coefficient increased with temperature, which indicated endothermic nature of the reaction. Enthalpy and entropy change during Cr(VI) extraction were positive and varied in the range of 37–49 kJ/mol and 114–155 J/mol, respectively. The free energy change was negative, confirming the feasibility and spontaneity of the mass transfer process. Results obtained suggest that EIMs are efficient and sustainable for extraction of Cr(VI) from wastewater.

  8. 超声波辅助提取橘子皮中果胶的研究%Research on Ultrasonic-assisted Extraction of Pectin From Orange Peel

    孙悦; 张双; 任铁强; 贾卓慧


    采用超声波辅助酸法从橘子皮中提取果胶。实验中对固液比、pH 值、提取温度和超声波提取时间等四个影响果胶提取率的因素分别进行考查,依据单因素实验结果进行正交试验。通过R和K值的比较,确定pH值、固液比对果胶提取率的影响较大,并确定最佳实验条件:pH值1.5、提取温度70℃、提取时间45 min、固液比20∶1,在该条件下果胶提取率可达到20.8%。采用红外光谱法对产品进行定性分析。%Pectin was extracted from orange peel by using ultrasonic assisted acid method. In the experiment process, effects of four factors including pH value, extraction temperature, reaction time and extracting solid-liquid ratio on pectin extraction yield were investigated, and then orthogonal test was utilized on the basis of results of single-factor test. Through comparing R and K value, it’s concluded that pH value and the extracting solid-liquid ratio have great influence on pectin extraction yield. The best experiment scheme was determined as follows:pH value 1.5, extraction temperature 70 ℃, reaction time 45 min, extracting solid-liquid ratio 1:20. Under above conditions, the pectin exacting field can reach 20.8%. Infrared spectrometry was used to carry out qualitative analysis of the product.

  9. Solid-Liquid Equilibria of Musk Ketone, Musk Xylene and 1,3-Dimethyl-2,4-Dinitro-5-Tert-Butyl Benzene

    曲红梅; 白鹏; 杨志才; 余国琮


    The solid-liquid equilibria of musk ketone + musk xylene, musk xylene+1,3-dimethyl-2,4-dinitro-5-tert-butyl benzene are measured by differential scanning calorimeter (DSC), these systems are proved to be simple eutectics. Moreover the melting points and the fusion enthalpies of musk ketone, musk xylene and 1,3-dimethyl-2,4-dinitro-5-tert-butyl benzene are also measured by the DSC. These solid-liquid equilibrium data and the heats of fusion are reported for the first time. Then UNIFAC model is used to correlate the solid-liquid equilibrium data.It is shown that the solid-liquid equilibria of musk systems can be predicted bv the UNIFAC model.

  10. Detection of Exposure to Environmental Pesticides During Pregnancy by the Analysis of Maternal Hair Using GC-MS.

    Posecion, N; Ostrea, E; Bielawski, D; Corrion, M; Seagraves, J; Jin, Y


    Several classes of pesticides were extracted from maternal hair by solid-liquid extraction. Analysis of their selected metabolites involved a methanolic/hydrochloric acid methyl ester derivatization and liquid-liquid extraction. Gas chromatography electron impact mass spectrometry was used to detect and quantify the pesticides and metabolites. Recovery of parent compounds and metabolites from the analysis of spiked hair ranged from 87 to 112% with coefficients of variation less than 11%. Limits of detection ranged from 0.031 to 5.88 μg g(-1). Analysis of hair samples from pregnant women in the Philippines showed maternal exposure during pregnancy to bioallethrin, propoxur, chlorpyrifos, pretilachlor and malathion.

  11. Flow phenomena of solid-liquid mixture in a rectangular cavity; Tanjun keijo kyabiti ni ryunyusuru koeki kongotai no ryudo gensho

    Sugiyama, A. [Osaka Univ., Osaka (Japan). Graduate Student; Onaka, I. [Osaka Univ., Osaka (Japan). Faculty of Engineering


    Flow phenomena of solid-liquid mixture are investigated assuming a case of rheocasting or casting of such solid-liquid mixtures as particulate-reinforced metal matrix composites. The free surface of the solid-liquid mixture is more stable when the mixture is ejected into a vertical cavity than that of a single phase liquid having the same mean viscosity as the apparent viscosity of the solid-liquid mixture. The critical velocity for filling with no surface disturbance is higher with the increase in the solid fraction. Regions with low concentration of particles are generated during the flow of solid-liquid mixture. The regions with low particle concentration are generated at the center and near the inlet area linearly at the boundary between the solid-liquid mixture flown into the cavity earlier and that with larger velocity flowing into later. The low concentration region at the center of rotary motion is generated immediately after the inflow into the rapidly expanding area, and seems to be held by the inertial force applied to solid particles. The linear low concentration region seems to be generated by the collision of particles having higher and lower velocities. 19 refs., 10 figs., 2 tabs.

  12. An Object Extraction Model Using Association Rules and Dependence Analysis


    Extracting objects from legacy systems is a basic step insystem's obje ct-orientation to improve the maintainability and understandability of the syst e ms. A new object extraction model using association rules an d dependence analysis is proposed. In this model data are classified by associat ion rules and the corresponding operations are partitioned by dependence analysis.

  13. The methodology of semantic analysis for extracting physical effects

    Fomenkova, M. A.; Kamaev, V. A.; Korobkin, D. M.; Fomenkov, S. A.


    The paper represents new methodology of semantic analysis for physical effects extracting. This methodology is based on the Tuzov ontology that formally describes the Russian language. In this paper, semantic patterns were described to extract structural physical information in the form of physical effects. A new algorithm of text analysis was described.

  14. Food Fish Identification from DNA Extraction through Sequence Analysis

    Hallen-Adams, Heather E.


    This experiment exposed 3rd and 4th y undergraduates and graduate students taking a course in advanced food analysis to DNA extraction, polymerase chain reaction (PCR), and DNA sequence analysis. Students provided their own fish sample, purchased from local grocery stores, and the class as a whole extracted DNA, which was then subjected to PCR,…

  15. Food Fish Identification from DNA Extraction through Sequence Analysis

    Hallen-Adams, Heather E.


    This experiment exposed 3rd and 4th y undergraduates and graduate students taking a course in advanced food analysis to DNA extraction, polymerase chain reaction (PCR), and DNA sequence analysis. Students provided their own fish sample, purchased from local grocery stores, and the class as a whole extracted DNA, which was then subjected to PCR,…

  16. Extracting Minerals from Seawater: An Energy Analysis

    Ugo Bardi


    Full Text Available The concept of recovering minerals from seawater has been proposed as a way of counteracting the gradual depletion of conventional mineral ores. Seawater contains large amounts of dissolved ions and the four most concentrated metal ones (Na, Mg, Ca, K are being commercially extracted today. However, all the other metal ions exist at much lower concentrations. This paper reports an estimate of the feasibility of the extraction of these metal ions on the basis of the energy needed. In most cases, the result is that extraction in amounts comparable to the present production from land mines would be impossible because of the very large amount of energy needed. This conclusion holds also for uranium as fuel for the present generation of nuclear fission plants. Nevertheless, in a few cases, mainly lithium, extraction from seawater could provide amounts of metals sufficient for closing the cycle of metal use in the economy, provided that an increased level of recycling can be attained.

  17. Phase diagrams and kinetics of solid-liquid phase transitions in crystalline polymer blends

    Matkar, Rushikesh A.

    A free energy functional has been formulated based on an order parameter approach to describe the competition between liquid-liquid phase separation and solid-liquid phase separation. In the free energy description, the assumption of complete solvent rejection from the crystalline phase that is inherent in the Flory diluent theory was removed as solvent has been found to reside in the crystalline phase in the form of intercalates. Using this approach, we have calculated various phase diagrams in binary blends of crystalline and amorphous polymers that show upper or lower critical solution temperature. Also, the discrepancy in the chi values obtained from different experimental methods reported in the literature for the polymer blend of poly(vinylidenefluoride) and poly(methylmethacrylate) has been discussed in the context of the present model. Experimental phase diagram for the polymer blend of poly(caprolactone) and polystyrene has also been calculated. Of particular importance is that the crystalline phase concentration as a function of temperature has been calculated using free energy minimization methods instead of assuming it to be pure. In the limit of complete immiscibility of the solvent in the crystalline phase, the Flory diluent theory is recovered. The model is extended to binary crystalline blends and the formation of eutectic, peritectic and azeotrope phase diagrams has been explained on the basis of departure from ideal solid solution behavior. Experimental eutectic phase diagram from literature of a binary blend of crystalline polymer poly(caprolactone) and trioxane were recalculated using the aforementioned approach. Furthermore, simulations on the spatio temporal dynamics of crystallization in blends of crystalline and amorphous polymers were carried out using the Ginzburg-Landau approach. These simulations have provided insight into the distribution of the amorphous polymer in the blends during the crystallization process. The simulated results

  18. The validation and preference among different EAM potentials to describe the solid-liquid transition of aluminum

    Jiang, Yewei; Luo, Jie; Wu, Yongquan


    Empirical potential is vital to the classic atomic simulation, especially for the study of phase transitions, as well as the solid-interface. In this paper, we attempt to set up a uniform procedure for the validation among different potentials before the formal simulation study of phase transitions of metals. Two main steps are involved: (1) the prediction of the structures of both solid and liquid phases and their mutual transitions, i.e. melting and crystallization; (2) the prediction of vital thermodynamic (the equilibrium melting point at ambient pressure) and dynamic properties (the degrees of superheating and undercooling). We applied this procedure to the testing of seven published embedded-atom potentials (MKBA (Mendelev et al 2008 Philos. Mag. 88 1723), MFMP (Mishin et al 1999 Phys. Rev. B 59 3393), MDSL (Sturgeon and Laird 2000 Phys. Rev. B 62 14720), ZM (Zope and Mishin 2003 Phys. Rev. B 68 024102), LEA (Liu et al 2004 Model. Simul. Mater. Sci. Eng. 12 665), WKG (Winey et al 2009 Model. Simul. Mater. Sci. Eng. 17 055004) and ZJW (Zhou et al 2004 Phys. Rev. B 69 144113)) for the description of the solid-liquid transition of Al. All the predictions of structure, melting point and superheating/undercooling degrees were compared with the experiments or theoretical calculations. Then, two of them, MKBA and MDSL, were proven suitable for the study of the solid-liquid transition of Al while the residuals were unqualified. However, potential MKBA is more accurate to predict the structures of solid and liquid, while MDSL works a little better in the thermodynamic and dynamic predictions of solid-liquid transitions.

  19. Density of Ni-Al Alloys in Liquid and Solid-Liquid Coexistence State Measured by a Modified Pycnometric Method

    Liang FANG; Feng XIAO; Zushu LI; Zainan TAO


    The density of Ni-Al alloys in both liquid state and solid-liquid coexistence state was measured with a modified pycnometric method. It was found that the density of NI-Al alloys decreases with increasing temperature and Al concentration in the alloys. The molar volume of liquid Ni-Al binary alloys increases with the increase of temperature and Al concentration. The partial molar volume of Al in NI-Al binary alloy was calculated approximately. The molar volume of liquid NI-Al alloy determined in the present work shows a negative deviation from the ideal linear molar volume.

  20. Experimental determination and prediction of (solid+liquid) phase equilibria for binary mixtures of heavy alkanes and fatty acids

    Benziane, Mokhtar; Khimeche, Kamel; Dahmani, Abdellah; Nezar, Sawsen; Trache, Djalal


    Solid-liquid equilibria for three binary mixtures, n-Eicosane (1) + Lauric acid (2), n-Tetracosane (1) + Stearic acid (2), and n-Octacosane (1) + Palmitic acid (2), were measured using a differential scanning calorimeter. Simple eutectic behaviour was observed for these systems. The experimental results were correlated by means of the modified UNIFAC (Larsen and Gmehling versions), UNIQUAC and ideal models. The root-mean-square deviations of the solubility temperatures for all measured data vary from 0.26 to 3.15 K and depend on the particular model used. The best solubility correlation was obtained with the UNIQUAC model.

  1. In Situ Observations of Interaction Between Particulate Agglomerates and an Advancing Planar Solid/Liquid Interface: Microgravity Experiments

    Sen, S.; Juretzko, F.; Stafanescu, D. M.; Dhindaw, B. K.; Curreri, P. A.


    Results are reported of directional solidification experiments on particulate agglomerate pushing and engulfment by a planar solid/liquid (s/l) interface. These experiments were conducted on the Space Shuttle Columbia during the United States Microgravity Payload 4 (USMP-4) Mission. It was found that the pushing to engulfment transition velocity, V(sub cr) for agglomerates depends not only on their effective size but also their orientation with respect to the s,1 interface. The analytical model for predicting V(sub cr) of a single particle was subsequently enhanced to predict V(sub cr) of the agglomerates by considering their shape factor and orientation.

  2. In-Situ Observations of Interaction Between Particulate Agglomerates and an Advancing Planar Solid/Liquid Interface: Microgravity Experiments

    Sen, S.; Juretzko, F.; Stefanescu, D. M.; Dhindaw, B. K.; Curreri, P. A.


    Results are reported of directional solidification experiments on particulate agglomerate pushing and engulfment by a planar solid/liquid (s/1) interface. These experiments were conducted on the Space Shuttle Columbia during the United States Microgravity Payload 4 (USMP-4) Mission. It was found that the pushing to engulfment transition velocity, V(sub ct),, for agglomerates depends not only on their effective size but also their orientation with respect to the s/l interface. The analytical model for predicting V(sub cr) of a single particle was subsequently enhanced to predict V(sub cr) of the agglomerates by considering their shape factor and orientation.

  3. Solid-Liquid Equilibria for Many-component Mixtures Using Cubic-Plus-Association (CPA) equation of state

    Fettouhi, André; Thomsen, Kaj


    In the creation of liquefied natural gas the formation of solids play a substantial role, hence detailed knowledge is needed about solid-liquid equilibria (SLE). In this abstract we shortly summarize the work we have carried out at CERE over the past year with SLE for many-component mixtures using...... the Cubic-Plus-Association (CPA) equation of state. Components used in this work are highly relevant to the oil and gas industry and include light and heavy hydrocarbons, alcohols, water and carbon dioxide....

  4. Free energy based melting point prediction by NVT simulation with solid-liquid two-phase configuration

    Inagaki, Taichi; Ishida, Toyokazu


    We propose a method for computing a melting point on the basis of the Gibbs free energy difference between the solid and liquid phases. The free energy difference is calculated from the average pressure obtained by performing a standard NVT simulation with a solid-liquid two-phase configuration. The method is validated by the melting point calculations of argon and benzene systems. In addition, the method is applied to a mannitol system, and the more reliable melting point than the previous estimate is successfully predicted. These results demonstrate that this method is very simple and useful to calculate melting points.

  5. Spontaneous mode-selection in the self-propelled motion of a solid/liquid composite driven by interfacial instability

    Takabatake, Fumi; Magome, Nobuyuki; Ichikawa, Masatoshi; Yoshikawa, Kenichi


    Spontaneous motion of a solid/liquid composite induced by a chemical Marangoni effect, where an oil droplet attached to a solid soap is placed on a water phase, was investigated. The composite exhibits various characteristic motions, such as revolution (orbital motion) and translational motion. The results showed that the mode of this spontaneous motion switches with a change in the size of the solid scrap. The essential features of this mode-switching were reproduced by ordinary differential equations by considering nonlinear friction with proper symmetry.

  6. Bubble Induced Disruption of a Planar Solid-Liquid Interface During Controlled Directional Solidification in a Microgravity Environment

    Grugel, Richard N.; Brush, Lucien N.; Anilkumar, Amrutur V.


    Pore Formation and Mobility Investigation (PFMI) experiments were conducted in the microgravity environment aboard the International Space Station with the intent of better understanding the role entrained porosity/bubbles play during controlled directional solidification. The planar interface in a slowing growing succinonitrile - 0.24 wt% water alloy was being observed when a nitrogen bubble traversed the mushy zone and remained at the solid-liquid interface. Breakdown of the interface to shallow cells subsequently occurred, and was later evaluated using down-linked data from a nearby thermocouple. These results and other detrimental effects due to the presence of bubbles during solidification processing in a microgravity environment are presented and discussed.

  7. Solid/liquid interfacial tension as a tool to study stability of lysozyme on adsorption to solid surfaces

    Krishnan, C. A.; Maheshwari, R.; Dhathathreyan, A.


    This work proposes the use of solid/liquid interfacial tension to study the stability of adsorbed lysozyme films on a solid surface using the contact angle of a liquid at the three phase contact line, in the presence of a denaturant, urea. Results suggest a direct correlation between this method with a standard technique like the fluorescence emission spectra and is measured with the same observable error as in the spectral methods. Further the technique provides a simple and direct handle to evaluate the homogeneity and degree of polarity of protein films on solid surfaces.

  8. Solid-liquid phase transitions in 3D systems with the inverse-power and Yukawa potentials

    Vaulina, O. S.; Koss, X. G.


    The melting of face-centered cubic (fcc) and body-centered cubic (bcc) crystal lattices was studied analytically and numerically for the systems of particles interacting via the inverse-power-law and Yukawa potentials. New approach is proposed for determination of the solid-liquid phase transitions in these systems. The suggested approach takes into account a nonlinearity (anharmonicity) of pair interaction forces and allows to correctly predict the conditions of melting of the systems with various isotropic pair interaction potentials. The obtained results are compared with the existing theoretical and numerical data.


    NI Jinren; MENG Xiaogang


    Vertical motion of particles was simulated by the Lagrangian method in one-dimensional solid-liquid two-phase flow. The conventional equation was modified by inserting a particle-particle interaction term,which was identified by Bagnold's experimental results. Effects of various forces have been examined under different particle concentrations. The results showed that the vertical sorting patterns are primarily determined by the joint action of inter-particle force and effective gravitational force, whereas the pace towards the steady sorting pattern was affected by Basset force and additional mass force.

  10. Microwave-assisted extraction of pectic polysaccharide from waste mango peel.

    Maran, J Prakash; Swathi, K; Jeevitha, P; Jayalakshmi, J; Ashvini, G


    This present study investigates the extraction characteristics and optimal parameters of the microwave-assisted extraction of pectin from waste mango peel (WMP). Microwave power, pH, time and solid-liquid ratio were selected as the extraction parameters and was studied by using Box-Behnken response surface design. The experimental data was analyzed by least square regression analysis method and a second order polynomial model was constructed for response from the experimental data. The constructed model was adequate to explain the relationships between independent variables and response. All studied factors had great influence on the yield of pectin by individually and interactively. The optimum microwave assisted extraction conditions for the highest pectin yield (28.86%) from WMP was found to be: microwave power of 413W, pH of 2.7, time of 134s and solid-liquid ratio of 1:18g/ml. The experimental value was well correlated with predicted value at the optimal condition.

  11. Electromembrane extraction for pharmaceutical and biomedical analysis

    Huang, Chuixiu; Seip, Knut Fredrik; Gjelstad, Astrid


    Electromembrane extraction (EME) was presented as a new microextraction concept in 2006, and since the introduction, substantial research has been conducted to develop this concept in different areas of analytical chemistry. To date, more than 100 research papers have been published on EME...

  12. Distribution functions to estimate radionuclide solid-liquid distribution coefficients in soils: the case of Cs

    Ramirez-Guinart, Oriol; Rigol, Anna; Vidal, Miquel [Analytical Chemistry department, Faculty of Chemistry, University of Barcelona, Mart i Franques 1-11, 08028, Barcelona (Spain)


    In the frame of the revision of the IAEA TRS 364 (Handbook of parameter values for the prediction of radionuclide transfer in temperate environments), a database of radionuclide solid-liquid distribution coefficients (K{sub d}) in soils was compiled with data coming from field and laboratory experiments, from references mostly from 1990 onwards, including data from reports, reviewed papers, and grey literature. The K{sub d} values were grouped for each radionuclide according to two criteria. The first criterion was based on the sand and clay mineral percentages referred to the mineral matter, and the organic matter (OM) content in the soil. This defined the 'texture/OM' criterion. The second criterion was to group soils regarding specific soil factors governing the radionuclide-soil interaction ('cofactor' criterion). The cofactors depended on the radionuclide considered. An advantage of using cofactors was that the variability of K{sub d} ranges for a given soil group decreased considerably compared with that observed when the classification was based solely on sand, clay and organic matter contents. The K{sub d} best estimates were defined as the calculated GM values assuming that K{sub d} values were always log-normally distributed. Risk assessment models may require as input data for a given parameter either a single value (a best estimate) or a continuous function from which not only individual best estimates but also confidence ranges and data variability can be derived. In the case of the K{sub d} parameter, a suitable continuous function which contains the statistical parameters (e.g. arithmetical/geometric mean, arithmetical/geometric standard deviation, mode, etc.) that better explain the distribution among the K{sub d} values of a dataset is the Cumulative Distribution Function (CDF). To our knowledge, appropriate CDFs has not been proposed for radionuclide K{sub d} in soils yet. Therefore, the aim of this works is to create CDFs for

  13. Investigating the influence of production conditions on the energy distribution between the solid, liquid and gaseous products of slow pyrolysis

    Crombie, Kyle; Masek, Ondrej


    calorific value due to the increased emission of volatiles. The higher heating value for the syngas was also shown to increase with temperature due to greater release of combustible gas species at higher temperatures. The impact of residence time and gas flow rate were not as clear as for temperature but still demonstrated decreasing biochar yields as the respective parameters were increased. However the greatest impact occurred at 350oC and diminished when temperature was increased to 650oC. An understanding of the influence that production conditions have on the long term stability of biochar as well as the energy content of the solid, liquid and gas fractions obtained from pyrolysis is critical towards the development of specifically engineered biochar to deliver a specific function be it for agricultural use, carbon storage, energy generation or combinations of the three.

  14. Extraction and analysis of indole derivatives from fungal biomass.

    Gartz, J


    The occurrence and extraction of indole derivatives in six species from four genera of higher fungi were investigated. By using pure methanol for extraction of the mushrooms analysis revealed the highest concentrations of psilocybin and baeocystin. The psilocin content of the species was higher by using aqueous solutions of alcohols than with methanol alone but was an artificial phenomenon caused by enzymatic destruction of psilocybin. The extraction with dilute acetic acid yielded better results than with the water containing alcohols. The simple one-step procedure with methanol for the quantitative extraction is still the safest method to obtain the genuine alkaloids from fungal biomass.

  15. Cavitation pulse extraction and centrifugal pump analysis

    Luo, Hong Lind Shaoran [University of Electronic Science and Technology of China, Chengdu (China); Yu, Bo; Qing, Biao [Xihua University, Chengdu (China)


    This study extracted cavitation pulses from hydrophone signals sampled in a centrifugal pump and analyzed their characteristics. The modified and simplified Empirical mode decomposition (EMD) algorithm was proposed for extracting cavitation pulses from strong background noise. Experimental results showed that EMD can effectively suppress noise and obtain clear cavitation pulses, facilitating the identification of the number of pulses associated with the degree of cavitation. The cavitation characteristics were modeled to predict the value of incipient cavitation. Then, we proposed a method for detecting the wear of the impeller surface. That is, the information on the impeller surface of the centrifugal pump, including the roughness of the impeller surface and its wear trends, were quantified based on the net positive suction head available of incipient cavitation. The findings indicate that the proposed technique is suitable for condition monitoring of the pump.

  16. Biochemical analysis of extracting fermented coconut oil


    Vegetable oil can be produced from a perennial plant such as coconut (Cocos nucifera L.). There are few techniques for coconut oil extraction, such as physical, chemical, and fermentative processes. The fermentation process uses microbial inoculum as starter. Ground coconut meat was soaked in warm water, than squeezed several times to get coconut milk. After being allowed to stand for 4-5 hours, it separated into two layers, cream and skim. Starter was prepared from a mixture of milk and coco...

  17. Linguistic feature analysis for protein interaction extraction

    Cornelis Chris


    Full Text Available Abstract Background The rapid growth of the amount of publicly available reports on biomedical experimental results has recently caused a boost of text mining approaches for protein interaction extraction. Most approaches rely implicitly or explicitly on linguistic, i.e., lexical and syntactic, data extracted from text. However, only few attempts have been made to evaluate the contribution of the different feature types. In this work, we contribute to this evaluation by studying the relative importance of deep syntactic features, i.e., grammatical relations, shallow syntactic features (part-of-speech information and lexical features. For this purpose, we use a recently proposed approach that uses support vector machines with structured kernels. Results Our results reveal that the contribution of the different feature types varies for the different data sets on which the experiments were conducted. The smaller the training corpus compared to the test data, the more important the role of grammatical relations becomes. Moreover, deep syntactic information based classifiers prove to be more robust on heterogeneous texts where no or only limited common vocabulary is shared. Conclusion Our findings suggest that grammatical relations play an important role in the interaction extraction task. Moreover, the net advantage of adding lexical and shallow syntactic features is small related to the number of added features. This implies that efficient classifiers can be built by using only a small fraction of the features that are typically being used in recent approaches.

  18. Biochemical analysis of extracting fermented coconut oil



    Full Text Available Vegetable oil can be produced from a perennial plant such as coconut (Cocos nucifera L.. There are few techniques for coconut oil extraction, such as physical, chemical, and fermentative processes. The fermentation process uses microbial inoculum as starter. Ground coconut meat was soaked in warm water, than squeezed several times to get coconut milk. After being allowed to stand for 4-5 hours, it separated into two layers, cream and skim. Starter was prepared from a mixture of milk and coconut water (1:9, v/v which enriched with 2% tomato extract, 0.5% urea, and 1.0% molasses and then preincubated for 5 days under agitation. Starter with different concentration (1.0; 2.5; 5.0; and 10% were added onto coconut milk and allowed to be fermented for over night. The extracting oil was analyzed for further experiment, especially, on its antibacterial activity. The maximum yield of 23% was achieved by using 2.5% starter. Total protein, fat, FFA, and cholesterol content of the fermented coconut oil were 0.05%, 96.45%, 0.29%, and 0.008%, respectively. The gas chromatogram showed that this oil contained high lauric acid (46.20%, and 13.94% miristic, 5.97% palmitic, 9.00% palmitoleic, and 19.73% stearic acid, respectively.

  19. Janus Solid-Liquid Interface Enabling Ultrahigh Charging and Discharging Rate for Advanced Lithium-Ion Batteries.

    Zheng, Jiaxin; Hou, Yuyang; Duan, Yandong; Song, Xiaohe; Wei, Yi; Liu, Tongchao; Hu, Jiangtao; Guo, Hua; Zhuo, Zengqing; Liu, Lili; Chang, Zheng; Wang, Xiaowei; Zherebetskyy, Danylo; Fang, Yanyan; Lin, Yuan; Xu, Kang; Wang, Lin-Wang; Wu, Yuping; Pan, Feng


    LiFePO4 has long been held as one of the most promising battery cathode for its high energy storage capacity. Meanwhile, although extensive studies have been conducted on the interfacial chemistries in Li-ion batteries,1-3 little is known on the atomic level about the solid-liquid interface of LiFePO4/electrolyte. Here, we report battery cathode consisted with nanosized LiFePO4 particles in aqueous electrolyte with an high charging and discharging rate of 600 C (3600/600 = 6 s charge time, 1 C = 170 mAh g(-1)) reaching 72 mAh g(-1) energy storage (42% of the theoretical capacity). By contrast, the accessible capacity sharply decreases to 20 mAh g(-1) at 200 C in organic electrolyte. After a comprehensive electrochemistry tests and ab initio calculations of the LiFePO4-H2O and LiFePO4-EC (ethylene carbonate) systems, we identified the transient formation of a Janus hydrated interface in the LiFePO4-H2O system, where the truncated symmetry of solid LiFePO4 surface is compensated by the chemisorbed H2O molecules, forming a half-solid (LiFePO4) and half-liquid (H2O) amphiphilic coordination environment that eases the Li desolvation process near the surface, which makes a fast Li-ion transport across the solid/liquid interfaces possible.

  20. Total enthalpy-based lattice Boltzmann method with adaptive mesh refinement for solid-liquid phase change

    Huang, Rongzong; Wu, Huiying


    A total enthalpy-based lattice Boltzmann (LB) method with adaptive mesh refinement (AMR) is developed in this paper to efficiently simulate solid-liquid phase change problem where variables vary significantly near the phase interface and thus finer grid is required. For the total enthalpy-based LB method, the velocity field is solved by an incompressible LB model with multiple-relaxation-time (MRT) collision scheme, and the temperature field is solved by a total enthalpy-based MRT LB model with the phase interface effects considered and the deviation term eliminated. With a kinetic assumption that the density distribution function for solid phase is at equilibrium state, a volumetric LB scheme is proposed to accurately realize the nonslip velocity condition on the diffusive phase interface and in the solid phase. As compared with the previous schemes, this scheme can avoid nonphysical flow in the solid phase. As for the AMR approach, it is developed based on multiblock grids. An indicator function is introduced to control the adaptive generation of multiblock grids, which can guarantee the existence of overlap area between adjacent blocks for information exchange. Since MRT collision schemes are used, the information exchange is directly carried out in the moment space. Numerical tests are firstly performed to validate the strict satisfaction of the nonslip velocity condition, and then melting problems in a square cavity with different Prandtl numbers and Rayleigh numbers are simulated, which demonstrate that the present method can handle solid-liquid phase change problem with high efficiency and accuracy.

  1. Phase interface effects in the total enthalpy-based lattice Boltzmann model for solid-liquid phase change

    Huang, Rongzong; Wu, Huiying


    In this paper, phase interface effects, including the differences in thermophysical properties between solid and liquid phases and the numerical diffusion across phase interface, are investigated for the recently developed total enthalpy-based lattice Boltzmann model for solid-liquid phase change, which has high computational efficiency by avoiding iteration procedure and linear equation system solving. For the differences in thermophysical properties (thermal conductivity and specific heat) between solid and liquid phases, a novel reference specific heat is introduced to improve the total enthalpy-based lattice Boltzmann model, which makes the thermal conductivity and specific heat decoupled. Therefore, the differences in thermal conductivity and specific heat can be handled by the dimensionless relaxation time and equilibrium distribution function, respectively. As for the numerical diffusion across phase interface, it is revealed for the first time and found to be induced by solid-liquid phase change. To reduce such numerical diffusion, multiple-relaxation-time collision scheme is exploited, and a special value (one fourth) for the so-called "magic" parameter, a combination of two relaxation parameters, is found. Numerical tests show that the differences in thermophysical properties can be correctly handled and the numerical diffusion across phase interface can be dramatically reduced. Finally, theoretical analyses are carried out to offer insights into the roles of the reference specific heat and "magic" parameter in the treatments of phase interface effects.

  2. Structure and property of metal melt Ⅰ:The number of residual bonds after solid-liquid phase changes


    Based on the mechanism of metal solid-liquid phase change and the theory of liquid metal’s micro-inhomogeneity,a physical model is established between latent heats of fusion and vaporization and the numbers of residual bonds and short-range ordered atoms at the melting point inside a metal melt.Meanwhile,the mathematical derivation and proof are also offered.This model produces the numbers of residual bonds and short-range ordered atoms after the solid-liquid phase change only by using basic parameters and thermophysical properties of the crystal structure.Therefore,it presents a more effective way to analyze the melt’s structural information.By using this model,this study calculates the numbers of residual bonds and short-range ordered atoms in Al and Ni melts.The calculated results are consistent with the experimental results.Simultaneously,this study discusses the atomic number’s influence on the numbers of residual bonds and short-range ordered atoms in the melts within the first(ⅠA) and second main group(ⅡA) elements.

  3. Interaction of SiC particles with moving solid-liquid interface during directional solidification of silicon

    Friedrich, J.; Reimann, C.; Jauss, T.; Cröll, A.; Sorgenfrei, T.


    In this work, the interaction of SiC particles, having sizes of 7 μm to 300 μm, with the moving solid-liquid interface during directional solidification of silicon was experimentally and theoretically investigated. This included both convective and nearly diffusive conditions. In the nearly diffusive regime under microgravity, the particles were incorporated at a lower growth velocity than in the convective regime under 1g conditions. The experimental data were compared to simple theoretical models allowing the calculation of the critical growth velocity for the incorporation of spherical particles in dependence of the particle size. It was found that the theoretical results could qualitatively explain the experimental observations when a proper set of equations for the forces acting on the particle and of the material constants are chosen. It can be concluded that sedimentation of the particles due to gravity seems to play a role only for large particles. On the other hand, melt flow might cause a lift force which would push the particles away from the solid-liquid interface, and thus would result in higher critical growth velocities under convective conditions, e.g. due to buoyancy convection. Therefore, a contribution of the missing lift force under μg conditions could lead to the smaller critical growth velocity for particle incorporation that is observed under microgravity.

  4. Investigation of the solid-liquid phase transition of carbon at 150 GPa with spectrally resolved X-ray scattering

    Helfrich, J.; Kraus, D.; Ortner, A.; Frydrych, S.; Schaumann, G.; Hartley, N. J.; Gregori, G.; Kettle, B.; Riley, D.; Carroll, D. C.; Notley, M. M.; Spindloe, C.; Roth, M.


    We have resolved the solid-liquid phase transition of carbon at pressures around 150 GPa. High-pressure samples of different temperatures were created by laser-driven shock compression of graphite and varying the initial density from 1.30 g/cm3 to 2.25 g/cm3. In this way, temperatures from 5700 K to 14,500 K could be achieved for relatively constant pressure according to hydrodynamic simulations. From measuring the elastic X-ray scattering intensity of vanadium K-alpha radiation at 4.95 keV at a scattering angle of 126°, which is very sensitive to the solid-liquid transition, we can determine whether the sample had transitioned to the fluid phase. We find that samples of initial density 1.3 g/cm3 and 1.85 g/cm3 are liquid in the compressed states, whereas samples close to the ideal graphite crystal density of 2.25 g/cm3 remain solid, probably in a diamond-like state.

  5. Numerical simulation on the performance of the vortex pump for transporting solid-liquid two-phase with light particles

    Mao, W. Y.; Song, P. Y.; Deng, Q. G.; Xu, H. J.


    With the purpose of studying performance of the vortex pump for transporting solid-liquid two-phase with light particles whose relative density smaller than 1, the numerical simulation of solid-liquid two phase flowing in the whole channel of a vortex pump with the particle diameter being 0.5 mm, 1 mm, 2 mm, 3 mm and the initial solid phase volume concentrations being 10%, 20% and 30% are respectively carried out by using the commercial software ANSYS Fluent by adopting RNG κ-ɛ turbulent flow model, Eulerian-Eulerian multi-phase flow model and SIMPLEC algorithm. The simulation results show that in the impeller region, the particles concentrate on the non-working surface of the blades, and the particles are rare on the working surface of the blades. As the initial solid phase volume concentration and particle diameter increase, the pump delivery head of vortex pump decrease. The pump delivery head of vortex pump with different initial solid phase concentrations and different particle diameters are predicted and compared with those obtained by an empirical formula, and they shows good agreement.

  6. Solid-liquid work of adhesion of coarse-grained models of n-hexane on graphene layers derived from the conditional reversible work method.

    Ardham, Vikram Reddy; Deichmann, Gregor; van der Vegt, Nico F A; Leroy, Frédéric


    We address the question of how reducing the number of degrees of freedom modifies the interfacial thermodynamic properties of heterogeneous solid-liquid systems. We consider the example of n-hexane interacting with multi-layer graphene which we model both with fully atomistic and coarse-grained (CG) models. The CG models are obtained by means of the conditional reversible work (CRW) method. The interfacial thermodynamics of these models is characterized by the solid-liquid work of adhesion WSL calculated by means of the dry-surface methodology through molecular dynamics simulations. We find that the CRW potentials lead to values of WSL that are larger than the atomistic ones. Clear understanding of the relationship between the structure of n-hexane in the vicinity of the surface and WSL is elucidated through a detailed study of the energy and entropy components of WSL. We highlight the crucial role played by the solid-liquid energy fluctuations. Our approach suggests that CG potentials should be designed in such a way that they preserve the range of solid-liquid interaction energies, but also their fluctuations in order to preserve the reference atomistic value of WSL. Our study thus opens perspectives into deriving CG interaction potentials that preserve the thermodynamics of solid-liquid contacts and will find application in studies that intend to address materials driven by interfaces.

  7. Solid-liquid work of adhesion of coarse-grained models of n-hexane on graphene layers derived from the conditional reversible work method

    Ardham, Vikram Reddy; Leroy, Frédéric, E-mail:, E-mail: [Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Strasse 4, 64287 Darmstadt (Germany); Deichmann, Gregor; Vegt, Nico F. A. van der, E-mail:, E-mail: [Center of Smart Interfaces, Technische Universität Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt (Germany)


    We address the question of how reducing the number of degrees of freedom modifies the interfacial thermodynamic properties of heterogeneous solid-liquid systems. We consider the example of n-hexane interacting with multi-layer graphene which we model both with fully atomistic and coarse-grained (CG) models. The CG models are obtained by means of the conditional reversible work (CRW) method. The interfacial thermodynamics of these models is characterized by the solid-liquid work of adhesion W{sub SL} calculated by means of the dry-surface methodology through molecular dynamics simulations. We find that the CRW potentials lead to values of W{sub SL} that are larger than the atomistic ones. Clear understanding of the relationship between the structure of n-hexane in the vicinity of the surface and W{sub SL} is elucidated through a detailed study of the energy and entropy components of W{sub SL}. We highlight the crucial role played by the solid-liquid energy fluctuations. Our approach suggests that CG potentials should be designed in such a way that they preserve the range of solid-liquid interaction energies, but also their fluctuations in order to preserve the reference atomistic value of W{sub SL}. Our study thus opens perspectives into deriving CG interaction potentials that preserve the thermodynamics of solid-liquid contacts and will find application in studies that intend to address materials driven by interfaces.

  8. Watermark Detection and Extraction Using Independent Component Analysis Method

    Yu Dan


    Full Text Available This paper proposes a new image watermarking technique, which adopts Independent Component Analysis (ICA for watermark detection and extraction process (i.e., dewatermarking. Watermark embedding is performed in the spatial domain of the original image. Watermark can be successfully detected during the Principle Component Analysis (PCA whitening stage. A nonlinear robust batch ICA algorithm, which is able to efficiently extract various temporally correlated sources from their observed linear mixtures, is used for blind watermark extraction. The evaluations illustrate the validity and good performance of the proposed watermark detection and extraction scheme based on ICA. The accuracy of watermark extraction depends on the statistical independence between the original, key and watermark images and the temporal correlation of these sources. Experimental results demonstrate that the proposed system is robust to several important image processing attacks, including some geometrical transformations—scaling, cropping and rotation, quantization, additive noise, low pass filtering, multiple marks, and collusion.

  9. Building Extraction from LIDAR Based Semantic Analysis

    YU Jie; YANG Haiquan; TAN Ming; ZHANG Guoning


    Extraction of buildings from LIDAR data has been an active research field in recent years. A scheme for building detection and reconstruction from LIDAR data is presented with an object-oriented method which is based on the buildings' semantic rules. Two key steps are discussed: how to group the discrete LIDAR points into single objects and how to establish the buildings' semantic rules. In the end, the buildings are reconstructed in 3D form and three common parametric building models (flat, gabled, hipped) are implemented.

  10. Extraction and Analysis of Terpenes/Terpenoids.

    Jiang, Zuodong; Kempinski, Chase; Chappell, Joe


    Terpenes/terpenoids constitute one of the largest classes of natural products, this is due to the incredible chemical diversity that can arise from the biochemical transformations of the relatively simple prenyl diphosphate starter units. All terpenes/terpenoids comprise a hydrocarbon backbone that is generated from the various length prenyl diphosphates (a polymer chain of prenyl units). Upon ionization (removal) of the diphosphate group, the remaining allylic carbocation intermediates can be coaxed down complex chemical cascades leading to diverse linear and cyclized hydrocarbon backbones, which can then be further modified with a wide range of functional groups (e.g. alcohol, ketones, etc.) and substituent additions (e.g. sugars, fatty acids). Because of this chemical diversity, terpenes/terpenoids have great industrial uses as flavors, fragrances, high grade lubricants, biofuels, agricultural chemicals and medicines. The protocols presented here focus on the extraction of terpenes/terpenoids from various plant sources and have been divided into extraction methods for terpenes/terpenoids with various levels of chemical decoration, from the relative small, nonpolar, volatile hydrocarbons to substantially large molecules with greater physical complexity due to their chemical modifications.

  11. Qualitative analysis of hexane flour extract of spelt

    Vujić Đura N.


    Full Text Available Gas chromatography with mass spectrometry (GC-MS was used for performing a qualitative analysis of the hexane flour extract of three samples of spelt. All the three samples were first treated with hexane and the obtained extracts were used for the analysis of the fatty acid lipid components. The transesterification reaction was performed using TMSH (trimethylsulfonium hydroxide, 0.2M in methanol, and the fatty acids were esterified from acylglycerol to methyl-esters. In all analyzed extracts, the predominant component was methyl linoleate, followed by methyl oleate and methyl palmitate. The subsequent tests, performed by cluster analysis, were used to compare the hexane flour extracts of different types of spelt. [Projekat Ministarstva nauke Republike Srbije, br. III46005 i br. TR 31066

  12. Facile synthesis of PbSe hollow nanostructure assemblies via a solid/liquid-phase chemical route and their electrogenerated chemiluminescence properties.

    Han, Min; Li, Yanrong; Niu, Hongyan; Liu, Lili; Chen, Kunji; Bao, Jianchun; Dai, Zhihui; Zhu, Jianming


    Spherical PbSe hollow nanostructure assemblies (HNSAs) were synthesized by a simple one-pot solid/liquid-phase reaction in which solid KPbI(3)⋅2 H(2)O and SeO(2) are heated in oleic acid/dodecylamine/1-octadecene at 250 °C for 30 min. XRD analysis shows that the obtained product is cubic-phase PbSe and well crystallized. FESEM and TEM images reveal that the obtained spherical PbSe assemblies are made up of small, irregular, and fused hollow nanostructure building blocks. On the basis of temperature- and time-dependent investigations as well as control experiments, molten-salt corrosion of solid PbSe nanocrystal aggregates formed in situ during the high-temperature ripening stage is suggested to explain the formation of such novel assemblies. Moreover, when the reaction temperature is further increased to 280 or 320 °C with other conditions unchanged, cubic and orthorhombic mixed-phase PbSe HNSAs is generated. The obtained PbSe HNSAs exhibit excellent electrogenerated chemiluminescence (ECL) performance. Two strong and stable emission peaks at about -1.4 and +1.5 V (vs. Ag/AgCl) are observed. In particular, the ECL intensity is influenced by the crystal phase of PbSe. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Sono-assisted extraction of alcohol-insoluble extract from Althaea rosea: purification and chemical analysis.

    Eskandari, Meghdad; Samavati, Vahid


    A Box-Behnken design (BBD) was used to evaluate the effects of ultrasonic power, extraction time, extraction temperature, and water to raw material ratio on extraction yield of alcohol-insoluble polysaccharide of Althaea rosea leaf (ARLP). Purification was carried out by dialysis method. Chemical analysis of ARLP revealed contained 12.69 ± 0.48% moisture, 79.33 ± 0.51% total sugar, 3.82 ± 0.21% protein, 11.25 ± 0.37% uronic acid and 3.77 ± 0.15% ash. The response surface methodology (RSM) showed that the significant quadratic regression equation with high R(2) (=0.9997) was successfully fitted for extraction yield of ARLP as function of independent variables. The overall optimum region was found to be at the combined level of ultrasonic power 91.85 W, extraction time 29.94 min, extraction temperature 89.78 °C, and the ratio of water to raw material 28.77 (mL/g). At this optimum point, extraction yield of ARLP was 19.47 ± 0.41%. No significant (p>0.05) difference was found between the actual and predicted (19.30 ± 0.075%) values. The results demonstrated that ARLP had strong scavenging activities on DPPH and hydroxyl radicals.

  14. A Research of Water Extraction of Pseudosciaena crocea Scale Collagen%水处理法提取大黄鱼鱼鳞胶原蛋白的研究

    柯佳颖; 陈庆标; 林型龙; 邱如新


    以大黄鱼鱼鳞为原材料对鱼鳞胶原蛋白的提取条件进行优化研究.首先选用水处理法对大黄鱼进行温度、料液比和时间的单因素分析,然后进行正交试验,以确定最优提取工艺.发现大黄鱼鱼鳞含水率为53.83%.最佳提取工艺为提取温度为80℃,提取时间为25 min,料液比为1∶40,得率为30.58%.%The conditions of extracting the collagen from Larimichthvs crocea scale with water treat-ment were studied.A single factor study was conducted for the extracting temperature,solid-liquid ratio and extracting time of univariate analysis before formal experiment to determine the optimal ex-traction process.Based on the experiment,it was found the moisture content of the Larimichthvs crocea scaleswas 53.83%,the proper condition of extracting collagen was 30.58% with extraction temperature 80 ℃,extraction time of 25 minutes,solid-liquid ratio was 1∶40.

  15. Antioxidant Capacity of Rapeseed Extracts Obtained by Conventional and Ultrasound-Assisted Extraction.

    Szydłowska-Czerniak, Aleksandra; Tułodziecka, Agnieszka


    Ultrasound-assisted extraction (UAE) and conventional solid-liquid extraction were applied to extract total antioxidants from two rapeseed varieties. The antioxidant capacities (AC) of winter and spring rapeseed cultivars were determined by four different analytical methods: ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), 2,2'-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS). The average AC of the studied rapeseed cultivars ranged between 4.21-10.03 mmol Trolox (TE)/100 g, 7.82-10.61 mmol TE/100 g, 8.11-51.59 mmol TE/100 g, 22.48-43.13 mmol TE/100 g for FRAP, CUPRAC, DPPH and ABTS methods, respectively. There are positive correlations between total phenolics (TPC = 804-1625 mg sinapic acid (SA)/100 g) and AC of the studied rapeseed extracts (r = 0.2650-0.9931). Results of the principal component analysis (PCA) indicate that there are differences between the total amounts of antioxidants in rapeseed samples extracted by different extraction techniques. Rapeseed extracts obtained after 18 min of ultrasonication revealed the highest content of total antioxidants. The UAE is a very useful, efficient and rapid technique of oilseed samples preparation for determination of AC by different analytical methods.

  16. Analysis of Platelet-Rich Plasma Extraction

    Fitzpatrick, Jane; Bulsara, Max K.; McCrory, Paul Robert; Richardson, Martin D.; Zheng, Ming Hao


    Background: Platelet-rich plasma (PRP) has been extensively used as a treatment in tissue healing in tendinopathy, muscle injury, and osteoarthritis. However, there is variation in methods of extraction, and this produces different types of PRP. Purpose: To determine the composition of PRP obtained from 4 commercial separation kits, which would allow assessment of current classification systems used in cross-study comparisons. Study Design: Controlled laboratory study. Methods: Three normal adults each donated 181 mL of whole blood, some of which served as a control and the remainder of which was processed through 4 PRP separation kits: GPS III (Biomet Biologics), Smart-Prep2 (Harvest Terumo), Magellan (Arteriocyte Medical Systems), and ACP (Device Technologies). The resultant PRP was tested for platelet count, red blood cell count, and white blood cell count, including differential in a commercial pathology laboratory. Glucose and pH measurements were obtained from a blood gas autoanalyzer machine. Results: Three kits taking samples from the “buffy coat layer” were found to have greater concentrations of platelets (3-6 times baseline), while 1 kit taking samples from plasma was found to have platelet concentrations of only 1.5 times baseline. The same 3 kits produced an increased concentration of white blood cells (3-6 times baseline); these consisted of neutrophils, leukocytes, and monocytes. This represents high concentrations of platelets and white blood cells. A small drop in pH was thought to relate to the citrate used in the sample preparation. Interestingly, an unexpected increase in glucose concentrations, with 3 to 6 times greater than baseline levels, was found in all samples. Conclusion: This study reveals the variation of blood components, including platelets, red blood cells, leukocytes, pH, and glucose in PRP extractions. The high concentrations of cells are important, as the white blood cell count in PRP samples has frequently been ignored

  17. Solid partitioning and solid-liquid distribution of {sup 210}Po and {sup 210}Pb in marine anoxic sediments: roads of Cherbourg at the northwestern France

    Connan, O. [Laboratoire de Radioecologie de Cherbourg-Octeville, Institut de Radioprotection et de Surete nucleaire (IRSN), Service d' Etudes et du Comportement des Radionucleides dans l' Environnement (SECRE), rue Max Pol Fouchet, 50130 Cherbourg-Octeville (France)], E-mail:; Boust, D. [Laboratoire de Radioecologie de Cherbourg-Octeville, Institut de Radioprotection et de Surete nucleaire (IRSN), Service d' Etudes et du Comportement des Radionucleides dans l' Environnement (SECRE), rue Max Pol Fouchet, 50130 Cherbourg-Octeville (France); Billon, G. [Laboratoire de Chimie Analytique et Marine, Universite des sciences et technologies de Lille, 59655 Villeneuve d' Ascq Cedex (France); Solier, L.; Rozet, M.; Bouderbala, S. [Laboratoire de Radioecologie de Cherbourg-Octeville, Institut de Radioprotection et de Surete nucleaire (IRSN), Service d' Etudes et du Comportement des Radionucleides dans l' Environnement (SECRE), rue Max Pol Fouchet, 50130 Cherbourg-Octeville (France)


    A sequential extraction protocol has been used to determine the solid-phase partition of {sup 210}Po and {sup 210}Pb in anoxic marine sediment from the roads of Cherbourg (France) in the central English Channel. Measurements were also obtained in pore waters, in which {sup 210}Po activities range between 1 and 20 mBq L{sup -1} and {sup 210}Pb activities between 2.4 and 3.8 mBq L{sup -1}, with highest activities in the topmost layer. These activities are higher than in seawater, suggesting that sediment act as a source of both {sup 210}Po and {sup 210}Pb for overlying water. The {sup 210}Po profile in the pore waters is apparently correlated with those obtained for Fe, Mn and SO{sub 4}{sup 2-}, suggesting an influence of early diagenetic processes on the {sup 210}Po solid-liquid distribution. In the sediment, {sup 210}Po is predominantly bound to organic matter or chromium reducible sulphides, and residuals (clay minerals and refractory oxides). Our results indicate that {sup 210}Po is not significantly bound to AVS, i.e. acid volatile sulphides: bioturbation could play a role by the early redistribution of {sup 210}Po bound to acid volatile sulphides in the sediment. {sup 210}Po, {sup 210}Pb and Pb exhibit differences in terms of distribution, probably due to a different mode of penetration in the sediment. This work provides information on solid and liquid distribution of {sup 210}Po and {sup 210}Pb in marine sediment. These data are very scarce in the litterature.

  18. The Stylistic Analysis of an Extract from The Rainbow



      This paper makes a detailed stylistic analysis of an extract from The Rainbow by Lawrence based on lexical features, grammatical features and figure of speech. Through the analysis, a better aesthetic appreciation and deeper understanding of the novel will be achieved.

  19. Solid-phase extraction procedures in systematic toxicological analysis

    Franke, J.P.; de Zeeuw, R.A


    In systematic toxicological analysis (STA) the substance(s) present is (are) not known at the start of the analysis. in such an undirected search the extraction procedure cannot be directed to a given substance but must be a general procedure where a compromise must be reached in that the substances

  20. Retinal image analysis: preprocessing and feature extraction

    Marrugo, Andres G; Millan, Maria S, E-mail: [Grup d' Optica Aplicada i Processament d' Imatge, Departament d' Optica i Optometria Univesitat Politecnica de Catalunya (Spain)


    Image processing, analysis and computer vision techniques are found today in all fields of medical science. These techniques are especially relevant to modern ophthalmology, a field heavily dependent on visual data. Retinal images are widely used for diagnostic purposes by ophthalmologists. However, these images often need visual enhancement prior to apply a digital analysis for pathological risk or damage detection. In this work we propose the use of an image enhancement technique for the compensation of non-uniform contrast and luminosity distribution in retinal images. We also explore optic nerve head segmentation by means of color mathematical morphology and the use of active contours.

  1. For solid-liquid two phase softness abrasive flow embedded real-time monitoring and control system%面向固-液两相软性磨粒流嵌入式实时测控系统

    计时鸣; 兰信鸿


    In order to solve the problems of flow pipe is to small to the conventional sensor for solid-liquid two phase softness abrasive flow,a monitoring method based on the vibration signal was proposed. Through the wavelet packet analysis of vibration signal, extraction signal characteristics were gotten. Using object-oriented technology, a kind of measurement and control software framework was developed, combined with finite state machine theory and embedded real-time operating system and programming methods of multitasking. Using Linux and DSP/BIOS RTOS, the double operating system signal processing technology was implemented,a multi-channel high speed data acquisition function was implemented on the intelligence embedded real-time measurement and control platform. The results indicate that it is easy to expand and interactive.%针对固-液两相软性磨粒流精密抛光方法中流道微小,无法采用常规直接信号传感器的问题,提出了一种基于二次信号-加速度振动信号的软性磨粒流监测方法.通过小波包分析提取了振动信号的特征.结合基于有限状态机理论与基于嵌入式实时操作系统的并发多任务的程序设计方法,采用面向对象技术开发了一种测控软件框架.采用Linux和DSP/BIOS RTOS实施了双操作系统信号处理技术,开发实现了一个面向软性磨粒流的,具有通用多通道高速数据采集功能的智能化嵌入式实时测控平台.研究结果表明,该系统具有易扩展与易交互的优点.

  2. Three-dimensional atomic force microscopy mapping at the solid-liquid interface with fast and flexible data acquisition.

    Söngen, Hagen; Nalbach, Martin; Adam, Holger; Kühnle, Angelika


    We present the implementation of a three-dimensional mapping routine for probing solid-liquid interfaces using frequency modulation atomic force microscopy. Our implementation enables fast and flexible data acquisition of up to 20 channels simultaneously. The acquired data can be directly synchronized with commercial atomic force microscope controllers, making our routine easily extendable for related techniques that require additional data channels, e.g., Kelvin probe force microscopy. Moreover, the closest approach of the tip to the sample is limited by a user-defined threshold, providing the possibility to prevent potential damage to the tip. The performance of our setup is demonstrated by visualizing the hydration structure above the calcite (10.4) surface in water.

  3. A Dynamic Model for the Interaction Between an Insoluble Particle and an Advancing Solid/Liquid Interface

    Catalina, A. V.; Mukherjee, S.; Stefanescu, D. M.


    Most models that describe the interaction of an insoluble particle with an advancing solid-liquid interface are based on the assumption of steady state. However, as demonstrated by experimental work, the process does not reach steady state until the particle is pushed for a while by the interface. In this work, a dynamic mathematical model was developed. The dynamic model demonstrates that this interaction is essentially non-steady state and that steady state eventually occurs only when solidification is conducted at sub-critical velocities. The model was tested for three systems: aluminum-zirconia particles, succinonitrilepolystyrene particles, and biphenyl-glass particles. The calculated values for critical velocity of the pushing/engulfment transition were in same range with the experimental ones.

  4. Free-Surface Optical Scattering as an Indicator of the Shock-Induced Solid-Liquid Phase Transition in Tin

    Stevens, G. D.; Lutz, S. S.; Marshall, B. R.; Turley, W. D.; Veeser, L. R.; Furlanetto, M. R.; Hixson, R. S.; Holtkamp, D. B.; Jensen, B. J.; Rigg, P. A.; Wilke, M. D.


    When highly polished metal surfaces melt upon release after shock loading, they exhibit features that suggest significant surface changes accompany the phase transition. The reflection of light from such surfaces changes from specular (pre-shock) to diffuse upon melting. A familiar manifestation of this phenomenon is the loss of signal light in VISAR measurements, which occurs at pressures high enough to melt the free surface. Unlike many other potential material phase-sensitive diagnostics (e.g., reflectometry, conductivity) that show relatively small (1%–10%) changes, the specularity of reflection provides a more sensitive and definitive indication of the solid-liquid phase transition. Data will be presented that support the hypothesis that specularity changes indicate melt in a way that can be measured easily and unambiguously.

  5. Microstructure and fractal characteristics of the solid-liquid interface forming during directional solidification of Inconel 718

    WANG Ling


    Full Text Available The solidification microstructure and fractal characteristics of the solid-liquid interfaces of Inconel 718, under different cooling rates during directional solidification, were investigated by using SEM. Results showed that 5 μm/s was the cellular-dendrite transient rate. The prime dendrite arm spacing (PDAS was measured by Image Tool and it decreased with the cooling rate increased. The fractal dimension of the interfaces was calculated and it changes from 1.204310 to 1.517265 with the withdrawal rate ranging from 10 to 100 μm/s. The physical significance of the fractal dimension was analyzed by using fractal theory. It was found that the fractal dimension of the dendrites can be used to describe the solidification microstructure and parameters at low cooling rate, but both the fractal dimension and the dendrite arm spacing are needed in order to integrally describe the evaluation of the solidification microstructure completely.

  6. A unified relation for the solid-liquid interface free energy of pure FCC, BCC, and HCP metals.

    Wilson, S R; Mendelev, M I


    We study correlations between the solid-liquid interface (SLI) free energy and bulk material properties (melting temperature, latent heat, and liquid structure) through the determination of SLI free energies for bcc and hcp metals from molecular dynamics (MD) simulation. Values obtained for the bcc metals in this study were compared to values predicted by the Turnbull, Laird, and Ewing relations on the basis of previously published MD simulation data. We found that of these three empirical relations, the Ewing relation better describes the MD simulation data. Moreover, whereas the original Ewing relation contains two constants for a particular crystal structure, we found that the first coefficient in the Ewing relation does not depend on crystal structure, taking a common value for all three phases, at least for the class of the systems described by embedded-atom method potentials (which are considered to provide a reasonable approximation for metals).

  7. Ultrafast solid-liquid-vapor phase change of a gold film induced by pico- to femtosecond lasers

    Huang, Jing; Zhang, Yuwen; Chen, J.K. [University of Missouri, Department of Mechanical and Aerospace Engineering, Columbia, MO (United States)


    Melting, vaporization and resolidification processes of thin gold film irradiated by a femtosecond pulse laser are studied numerically. The nonequilibrium heat transfer in electrons and lattice is described using a two-temperature model. The solid-liquid interfacial velocity, as well as elevated melting temperature and depressed solidification temperature, is obtained by considering the interfacial energy balance and nucleation dynamics. An iterative procedure based on energy balance and gas kinetics law to track the location of liquid-vapor interface is utilized to obtain the material removal by vaporization. The effect of surface heat loss by thermal radiation was discussed. The influences of laser fluence and duration on the evaporation process are studied. Results show that higher laser fluence and shorter laser pulse width lead to higher interfacial temperature, deeper melting and ablation depths. (orig.)

  8. Microstructure and fractal characteristics of the solid-liquid interface forming during directional solidification of Inconel 718


    The solidification microstructure and fractal characteristics of the solid-liquid interfaces of Inconel718, under different cooling rates during directional solidification, ware investigated by using SEM. Results showed that 5 μm/s was the cellular-dendrite transient rate. The prime dendrite arm spacing (PDAS) was measured by Image Tool and it decreased with the cooling rate increased. The fractal dimension of the interfaces was calculated and it changes from 1.204310 to 1.517265 with the withdrawal rate ranging from 10 to 100 μm/s. The physical significance of the fractal dimension was analyzed by using fractal theory. It was found that the fractal dimension of the dendrites can be used to describe the solidification microstructure and parameters at low cooling rate, but both the fractal dimension and the dendrite arm spacing are needed in order to integrally describe the evaluation of the solidification microstructure completely.

  9. Solid-liquid state pressure bonding of Si3N4 ceramics with aluminum based alloys and its mechanism


    Solid-liquid state pressure bonding of Si3N4 ceramics with aluminum based alloys, which contain a small amount of intermetallic compounds Al3Ti or Al3Zr, was investigated. With this new method, the heat resistant properties of the bonding zone metal are improved, and the joints' strengths at high temperature is increased. The joints' shear strength at room temperature and at 600  ℃ reach 126~133  MPa and 32~34  MPa, respectively, with suitable bonding pressure. The reaction between aluminum and Si3N4 ceramics, which produces Al-Si-N-O type compounds is the dominant interfacial reaction, while the reactions between the second active element Ti or Zr in the aluminum based alloys and Si3N4 ceramics also occur to some extend.

  10. A unified relation for the solid-liquid interface free energy of pure FCC, BCC, and HCP metals

    Wilson, S. R.; Mendelev, M. I.


    We study correlations between the solid-liquid interface (SLI) free energy and bulk material properties (melting temperature, latent heat, and liquid structure) through the determination of SLI free energies for bcc and hcp metals from molecular dynamics (MD) simulation. Values obtained for the bcc metals in this study were compared to values predicted by the Turnbull, Laird, and Ewing relations on the basis of previously published MD simulation data. We found that of these three empirical relations, the Ewing relation better describes the MD simulation data. Moreover, whereas the original Ewing relation contains two constants for a particular crystal structure, we found that the first coefficient in the Ewing relation does not depend on crystal structure, taking a common value for all three phases, at least for the class of the systems described by embedded-atom method potentials (which are considered to provide a reasonable approximation for metals).

  11. Measurement of solid-liquid interfacial energy in the In-Bi eutectic alloy at low melting temperature

    Marasli, N [Department of Physics, Faculty of Arts and Sciences, Erciyes University, 38039 Kayseri (Turkey); Akbulut, S [Institute of Science and Technology, Department of Physics, Erciyes University, 38039 Kayseri (Turkey); Ocak, Y [Department of Physics, Faculty of Arts and Sciences, Erciyes University, 38039 Kayseri (Turkey); Keslioglu, K [Department of Physics, Faculty of Arts and Sciences, Erciyes University, 38039 Kayseri (Turkey); Boeyuek, U [Institute of Science and Technology, Department of Physics, Erciyes University, 38039 Kayseri (Turkey); Kaya, H [Department of Science Education, Education Faculty, Erciyes University, 38039 Kayseri (Turkey); Cadirli, E [Department of Physics, Faculty of Arts and Sciences, Nigde University, Nigde (Turkey)


    The Gibbs-Thomson coefficient and solid-liquid interfacial energy of the solid In solution in equilibrium with In Bi eutectic liquid have been determined to be (1.46 {+-} 0.07) x 10{sup -7} K m and (40.4 {+-} 4.0) x 10{sup -3} J m{sup -2} by observing the equilibrated grain boundary groove shapes. The grain boundary energy of the solid In solution phase has been calculated to be (79.0 {+-} 8.7) x 10{sup -3} J m{sup -2} by considering force balance at the grain boundary grooves. The thermal conductivities of the In-12.4 at.% Bi eutectic liquid phase and the solid In solution phase and their ratio at the eutectic melting temperature (72 deg. C) have also been measured with radial heat flow apparatus and Bridgman-type growth apparatus.

  12. Dynamic interfacial properties of poly(ethylene glycol)-modified ferritin at the solid/liquid interface.

    Kumashiro, Yoshikazu; Ikezoe, Yasuhiro; Tamada, Kaoru; Hara, Masahiko


    Poly(ethylene glycol)-modified ferritins (PEG-ferritins) with various molecular weights were synthesized by the grafting method, and their dynamic interfacial properties at the solid/liquid interface were investigated. The number of PEG grafted to ferritins was controlled by the amount of 1,1'-carbonyldiimidazole-modified PEG adding to the reaction solution. The adsorption kinetics and energy dissipation of PEG-ferritins onto bare Si substrate and amino-modified Si substrate were investigated with a quartz crystal microbalance (QCM) in 10 mM bis-Tris/HCl buffer (pH 5.8), while their morphologies were characterized by scanning electron microscopy (SEM). The adsorption dynamics of PEG-ferritins onto amino-modified Si substrate were quite different from those of unmodified ferritin, which can be reasonably interpreted by the desorption capability of PEG-ferritins on the surface attributed to amphiphilicity and the high-chain mobility of PEG chains.

  13. Smart Extraction and Analysis System for Clinical Research.

    Afzal, Muhammad; Hussain, Maqbool; Khan, Wajahat Ali; Ali, Taqdir; Jamshed, Arif; Lee, Sungyoung


    With the increasing use of electronic health records (EHRs), there is a growing need to expand the utilization of EHR data to support clinical research. The key challenge in achieving this goal is the unavailability of smart systems and methods to overcome the issue of data preparation, structuring, and sharing for smooth clinical research. We developed a robust analysis system called the smart extraction and analysis system (SEAS) that consists of two subsystems: (1) the information extraction system (IES), for extracting information from clinical documents, and (2) the survival analysis system (SAS), for a descriptive and predictive analysis to compile the survival statistics and predict the future chance of survivability. The IES subsystem is based on a novel permutation-based pattern recognition method that extracts information from unstructured clinical documents. Similarly, the SAS subsystem is based on a classification and regression tree (CART)-based prediction model for survival analysis. SEAS is evaluated and validated on a real-world case study of head and neck cancer. The overall information extraction accuracy of the system for semistructured text is recorded at 99%, while that for unstructured text is 97%. Furthermore, the automated, unstructured information extraction has reduced the average time spent on manual data entry by 75%, without compromising the accuracy of the system. Moreover, around 88% of patients are found in a terminal or dead state for the highest clinical stage of disease (level IV). Similarly, there is an ∼36% probability of a patient being alive if at least one of the lifestyle risk factors was positive. We presented our work on the development of SEAS to replace costly and time-consuming manual methods with smart automatic extraction of information and survival prediction methods. SEAS has reduced the time and energy of human resources spent unnecessarily on manual tasks.

  14. Monte Carlo simulations of the solid-liquid transition in hard spheres and colloid-polymer mixtures.

    Zykova-Timan, T; Horbach, J; Binder, K


    Monte Carlo simulations at constant pressure are performed to study coexistence and interfacial properties of the liquid-solid transition in hard spheres and in colloid-polymer mixtures. The latter system is described as a one-component Asakura-Oosawa (AO) model where the polymer's degrees of freedom are incorporated via an attractive part in the effective potential for the colloid-colloid interactions. For the considered AO model, the polymer reservoir packing fraction is eta(p) (r)=0.1 and the colloid-polymer size ratio is q[triple bond]sigma(p)/sigma=0.15 (with sigma(p) and sigma as the diameter of polymers and colloids, respectively). Inhomogeneous solid-liquid systems are prepared by placing the solid fcc phase in the middle of a rectangular simulation box, creating two interfaces with the adjoined bulk liquid. By analyzing the growth of the crystalline region at various pressures and for different system sizes, the coexistence pressure p(co) is obtained, yielding p(co)=11.576 k(B)T/sigma(3) for the hard-sphere system and p(co)=8.00 k(B)T/sigma(3) for the AO model (with k(B) as the Boltzmann constant and T as the temperature). Several order parameters are introduced to distinguish between solid and liquid phases and to describe the interfacial properties. From the capillary-wave broadening of the solid-liquid interface, the interfacial stiffness is obtained for the (100) crystalline plane, giving the values gamma approximately 0.49 k(B)T/sigma(2) for the hard-sphere system and gamma approximately 0.95 k(B)T/sigma(2) for the AO model.

  15. Application of solid-liquid TPPBs to the production of L-phenylacetylcarbinol from benzaldehyde using Candida utilis.

    Khan, Tanya R; Daugulis, Andrew J


    The biotransformation of benzaldehyde and glucose to L-phenylacetylcarbinol (PAC) using Candida utilis was demonstrated in a solid-liquid two-phase partitioning bioreactor (TPPB) with the aim of reducing substrate, product, and by-product toxicity via sequestration. Previous work in the field had used octanol as the sequestering phase of liquid-liquid TPPBs but was limited by the toxic effects of octanol on C. utilis. To improve solvent selection in any future studies, the critical log P of C. utilis was determined in the current study to be 4.8 and can be used to predict biocompatible solvents. Bioavailability tests showed alkanes and alkenes to be non-bioavailable. As polymers are biocompatible and non-bioavailable, a wide range of commercially available polymers was screened and it was demonstrated that polymer softness plays a key role in absorptive capability. The polymer Hytrel G3548L was selected as the second phase to sequester benzaldehyde, PAC, and benzyl alcohol, with partition coefficients of 35, 7.5, and 10, respectively. With a 9% by volume partitioning phase, 13.6 g/L biomass of C. utilis achieved an overall PAC concentration of 11 g/L, a 1.9-fold improvement over the single-phase case. Benzyl alcohol concentration was 4.5 g/L, a 1.6-fold reduction. The volumetric productivity was 0.85 g/L h, a 1.2-fold improvement over the single-phase system. These results demonstrate a promising starting point for solid-liquid TPPBs for PAC production. © 2010 Wiley Periodicals, Inc.

  16. Determination of cocaine in postmortem human liver exposed to overdose. Application of an innovative and efficient extraction/clean up procedure and gas chromatography-mass spectrometry analysis.

    Magalhães, Elisângela Jaqueline; Ribeiro de Queiroz, Maria Eliana Lopes; Penido, Marcus Luiz de Oliveira; Paiva, Marco Antônio Ribeiro; Teodoro, Janaína Aparecida Reis; Augusti, Rodinei; Nascentes, Clésia Cristina


    A simple and efficient method was developed for the determination of cocaine in post-mortem samples of human liver via solid-liquid extraction with low temperature partitioning (SLE-LTP) and analysis by gas chromatography coupled to mass spectrometry (GC-MS). The extraction procedure was optimized by evaluating the influence of the following variables: pH of the extract, volume and composition of the extractor solvent, addition of a sorbent material (PSA: primary-secondary amine) and NaCl to clean up and increase the ionic strength of the extract. A bovine liver sample that was free of cocaine was used as a blank for the optimization of the SLE-LTP extraction procedure. The highest recovery was obtained when crushed bovine liver (2g) was treated with 2mL of ultrapure water plus 8mL of acetonitrile at physiological pH (7.4). The results also indicated no need for using PSA and NaCl. The complete analytical procedure was validated for the following figures of merit: selectivity, lower limit of quantification (LLOQ), calibration curve, recovery, precision and accuracy (for within-run and between-run experiments), matrix effect, dilution integrity and stability. The within-run and between-run precision (at four levels) varied from 2.1% to 9.4% and from 4.0% to 17.0%, respectively. A maximum deviation of 11.62% for the within-run and between-run accuracies in relation to the nominal concentrations was observed. Moreover, the LLOQ value for cocaine was 50.0ngg(-1) whereas no significant effects were noticed in the assays of dilution integrity and stability. To assess its overall performance, the optimized method was applied to the analysis of eight human liver samples collected from individuals who died due to the abusive consumption of cocaine. Due to the existence of a significant matrix effect, a blank human liver was used to construct a matrix-matched analytical curve. The concentrations of cocaine found in these samples ranged from 333.5 to 5969ngg(-1). Copyright

  17. Magnetic Solid Phase Extraction Applied to Food Analysis

    Israel S. Ibarra


    Full Text Available Magnetic solid phase extraction has been used as pretreatment technique for the analysis of several compounds because of its advantages when it is compared with classic methods. This methodology is based on the use of magnetic solids as adsorbents for preconcentration of different analytes from complex matrices. Magnetic solid phase extraction minimizes the use of additional steps such as precipitation, centrifugation, and filtration which decreases the manipulation of the sample. In this review, we describe the main procedures used for synthesis, characterization, and application of this pretreatment technique which were applied in food analysis.

  18. Characterization of the key aroma compounds in beef extract using aroma extract dilution analysis.

    Takakura, Yukiko; Sakamoto, Tomohiro; Hirai, Sachi; Masuzawa, Takuya; Wakabayashi, Hidehiko; Nishimura, Toshihide


    Aroma extract dilution analysis (AEDA) of an ether extract prepared from beef extract (BE) and subsequent identification experiments led to the determination of seven aroma-active compounds in the flavor dilution (FD) factor range of 32-128. Omission experiments to select the most aroma-active compounds from the seven aroma compounds suggested that 2,3,5-trimethyl pyrazine, 1-octen-3-ol, 3-methylbutanoic acid, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone were the main active compounds contributing to the aroma of BE. Aroma recombination, addition, and omission experiments of the four aroma compounds in taste-reconstituted BE showed that each compound had an individual aroma profile. A comparison of the overall aroma between this recombination mixture and BE showed a high similarity, suggesting that the key aroma compounds had been identified successfully.

  19. Optimization of Extraction Technology of Ellagic Acid from Pomegranate Peels with Orthogonal Experiment


    [Objective] This study aimed to investigate the optimal condition for extrac- tion of ellagic acid from pomegranate peels. [Method] With ellagic acid yield as an indicator, ultrasound extraction method was adopted to extract the ellagic acid from pomegranate peels, and the concentration of ellagic acid was measured by using ul- traviolet spectrophotometry; L9(34) orthogonal experiment was designed with four fac- tors at three levels, to investigate the effect of extraction temperature, extraction du- ration, solid-liquid ratio and ultrasound power on extraction rate of ellagic acid. [Re- sult] The optimal extraction condition for ellagic acid is extraction temperature of 30 ~C, solid-liquid ratio of 1:200, extraction duration of 20 min, and ultrasound power of 50 W. The relationship between primary and secondary factors affecting experimental indicators was solid-liquid ratio 〉 extraction duration 〉 ultrasound power 〉 extraction temperature. [Conclusion] Solid-liquid ratio has the maximum effect on extraction rate of ellagic acid. The ellagic acid extraction technology identified in this study is rea- sonable and feasible.

  20. A Procedure for the supercritical fluid extraction of coal samples, with subsequent analysis of extracted hydrocarbons

    Kolak, Jonathan J.


    Introduction: This report provides a detailed, step-by-step procedure for conducting extractions with supercritical carbon dioxide (CO2) using the ISCO SFX220 supercritical fluid extraction system. Protocols for the subsequent separation and analysis of extracted hydrocarbons are also included in this report. These procedures were developed under the auspices of the project 'Assessment of Geologic Reservoirs for Carbon Dioxide Sequestration' (see to investigate possible environmental ramifications associated with CO2 storage (sequestration) in geologic reservoirs, such as deep (~1 km below land surface) coal beds. Supercritical CO2 has been used previously to extract contaminants from geologic matrices. Pressure-temperature conditions within deep coal beds may render CO2 supercritical. In this context, the ability of supercritical CO2 to extract contaminants from geologic materials may serve to mobilize noxious compounds from coal, possibly complicating storage efforts. There currently exists little information on the physicochemical interactions between supercritical CO2 and coal in this setting. The procedures described herein were developed to improve the understanding of these interactions and provide insight into the fate of CO2 and contaminants during simulated CO2 injections.

  1. USDA-ARS research update: Improved solid-liquid separation using polymers in flushing systems and new technology to recover the ammonia from covered lagoons

    Part 1: Improved method for recovery of organic solids from diluted swine manure: Solid-liquid separation of the raw manure increases the capacity of decision making and opportunities for treatment. The high-rate separation up-front using flocculants allows recovery of most of the organic compounds,...


    Demyanenko DV


    Full Text Available The purpose of this work was to make qualitative and quantitative analysis of phenolic biologically active substances (BAS in the extracts produced from lime flowers with condensed gases, using method of high-performance liquid chromatography (HPLC. Materials and methods: materials for this study were the extracts obtained by consequent processing of the herbal drug and marcs thereof with various condensed gases: difluorochloromethane (Freon R22, difluoromethane (Freon R32, azeotropic mixture of difluoromethane with pentafluoroethane (Freon 410A and freon-ammonium mixture. Extracts obtained with the latter were subjected to further fractionation by liquidliquid separation into hexane, chloroform, ethyl acetate and aqueous-alcohol phases. Besides, the supercritical СО2 extract, obtained from the herbal drug under rather strong conditions (at temperature 60°С and pressure 400 bar, was studied in our previous research. Presence of phenolic BAS and their quantity in the researched samples were determined by method of HPLC with UVspectrometric detection. Results and discussion: It has been found that Freon R22 extracted trace amounts of rutin from lime flowers – its content was only 0.08% of the total extract weight. On the other hand, Freons R32 and R410А showed good selectivity to moderately polar BAS of lime flowers (derivatives of flavonoids and hydroxycinnamic acids: in particular, the extract obtained with freon R32 contained about 1.3% of the total phenolic substances, and it was the only one of the investigated condensed gases used by us which took the basic flavonoid of lime flowers tiliroside – its content was 0.42% of extract weight. Also Freons R32 and R410А were able to withdraw another compound dominating among phenolic substances in the yielded extracts. Its quantity was rather noticeable – up to 0.87% of extract weight. This substance was not identified by existing database, but its UV-spectrum was similar to those of

  3. 长链脂肪酸系列固-液相变动力学的研究%Kinetic Study of Solid-liquid Phase Change in Fatty Acids

    王红; 张建军; 武克忠; 刘晓地; 张建玲


    The solid-liquid phase change kinetics in Capric,Lauric and Palmitic acid has been studied by DSC. Kissinger and Ozawa methods have been applied to determine the activation energy and reaction order of solid-liquid phase change. The results from two methods are in agreement.

  4. Direct Sampling and Analysis from Solid Phase Extraction Cards using an Automated Liquid Extraction Surface Analysis Nanoelectrospray Mass Spectrometry System

    Walworth, Matthew J [ORNL; ElNaggar, Mariam S [ORNL; Stankovich, Joseph J [ORNL; WitkowskiII, Charles E. [Protein Discovery, Inc.; Norris, Jeremy L [ORNL; Van Berkel, Gary J [ORNL


    Direct liquid extraction based surface sampling, a technique previously demonstrated with continuous flow and autonomous pipette liquid microjunction surface sampling probes, has recently been implemented as the Liquid Extraction Surface Analysis (LESA) mode on the commercially available Advion NanoMate chip-based infusion nanoelectrospray ionization system. In the present paper, the LESA mode was applied to the analysis of 96-well format custom solid phase extraction (SPE) cards, with each well consisting of either a 1 or 2 mm diameter monolithic hydrophobic stationary phase. These substrate wells were conditioned, loaded with either single or multi-component aqueous mixtures, and read out using the LESA mode of a TriVersa NanoMate or a Nanomate 100 coupled to an ABI/Sciex 4000QTRAPTM hybrid triple quadrupole/linear ion trap mass spectrometer and a Thermo LTQ XL linear ion trap mass spectrometer. Extraction conditions, including extraction/nanoESI solvent composition, volume, and dwell times, were optimized in the analysis of targeted compounds. Limit of detection and quantitation as well as analysis reproducibility figures of merit were measured. Calibration data was obtained for propranolol using a deuterated internal standard which demonstrated linearity and reproducibility. A 10x increase in signal and cleanup of micromolar Angiotensin II from a concentrated salt solution was demonstrated. Additionally, a multicomponent herbicide mixture at ppb concentration levels was analyzed using MS3 spectra for compound identification in the presence of isobaric interferences.

  5. High temperature investigation of the solid/liquid transition in the PuO2-UO2-ZrO2 system

    Quaini, A.; Guéneau, C.; Gossé, S.; Sundman, B.; Manara, D.; Smith, A. L.; Bottomley, D.; Lajarge, P.; Ernstberger, M.; Hodaj, F.


    The solid/liquid transitions in the quaternary U-Pu-Zr-O system are of great interest for the analysis of core meltdown accidents in Pressurised Water Reactors (PWR) fuelled with uranium-dioxide and MOX. During a severe accident the Zr-based cladding can become completely oxidised due to the interaction with the oxide fuel and the water coolant. In this framework, the present analysis is focused on the pseudo-ternary system UO2-PuO2-ZrO2. The melting/solidification behaviour of five pseudo-ternary and one pseudo-binary ((PuO2)0.50(ZrO2)0.50) compositions have been investigated experimentally by a laser heating method under pre-set atmospheres. The effects of an oxidising or reducing atmosphere on the observed melting/freezing temperatures, as well as the amount of UO2 in the sample, have been clearly identified for the different compositions. The oxygen-to-metal ratio is a key parameter affecting the melting/freezing temperature because of incongruent vaporisation effects. In parallel, a detailed thermodynamic model for the UO2-PuO2-ZrO2 system has been developed using the CALPHAD method, and thermodynamic calculations have been performed to interpret the present laser heating results, as well as the high temperature behaviour of the cubic (Pu,U,Zr)O2±x-c mixed oxide phase. A good agreement was obtained between the calculated and experimental data points. This work enables an improved understanding of the major factors relevant to severe accident in nuclear reactors.

  6. Analysis preliminary phytochemical raw extract of leaves Nephrolepis pectinata

    Natally Marreiros Gomes


    Full Text Available The Nephrolepis pectinata popularly known as paulista fern, ladder-heaven, cat tail, belongs to the family Davalliaceae. For the beauty of the arrangements of their leaves ferns are quite commercialized in Brazil, however, have not been described in the literature studies on their pharmacological potential. Thus, the objective of this research was to analyze the phytochemical properties of the crude extract of the leaves of Nephrolepis pectinata. To perform the phytochemical analysis were initially made the collection of the vegetable, preparation of voucher specimen, washing, drying and grinding. Then, extraction by percolation method and end the phytochemical analysis. Preliminary results phytochemicals the crude extract of the leaves of Nephrolepis pectinata tested positive for reducing sugars, phenols/tannins (catechins tannins and catechins.

  7. Single corn kernel aflatoxin B1 extraction and analysis method

    Aflatoxins are highly carcinogenic compounds produced by the fungus Aspergillus flavus. Aspergillus flavus is a phytopathogenic fungus that commonly infects crops such as cotton, peanuts, and maize. The goal was to design an effective sample preparation method and analysis for the extraction of afla...

  8. Preprocessing and exploratory analysis of chromatographic profiles of plant extracts

    Hendriks, M.M.W.B.; Cruz-Juarez, L.; Bont, de D.; Hall, R.D.


    The characterization of herbal extracts to compare samples from different origin is important for robust production and quality control strategies. This characterization is now mainly performed by analysis of selected marker compounds. Metabolic fingerprinting of full metabolite profiles of plant ex

  9. Chemical analysis of Ginkgo biloba leaves and extracts

    Beek, van T.A.


    The chemical analysis and quality control of Ginkgo leaves and extracts is reviewed. Important constituents present in the medicinally used leaves are the terpene trilactones, i.e., ginkgolides A, B, C, J and bilobalide, many flavonol glycosides, biflavones, proanthocyanidins, alkylphenols, simple p

  10. Optimization Experiment to Extract Citronellol from Pelargonium graveolens with Ethanol%利用乙醇提取香叶天竺葵中香茅醇研究

    陈鹏; 谭乐和; 徐飞; 刘向阳; 郝朝运; 吴刚; 张翠玲


    本文利用香叶天竺葵的叶片,对香叶天竺葵中香茅醇的提取率进行研究.对提取香茅醇的最适乙醇浓度、温度、时间、料液比分别进行了测定.结果表明,乙醇提取法的最佳工艺条件为乙醇浓度75%、温度40℃、时间4h、料液比1:20的最佳组合,在该条件下香茅醇提取率可达0.88 mg/g.%The extraction rate of citronellol from leaves of Pelargonium graveolens were determined. The optimum ethanol concentration, temperature, time, and solid-liquid ratio for extracting the citronellol were examined. The results of statistical analysis showed that the ideal extraction condition was as follows; 75 % ethanol concentration, 40℃, 4 h, and 1:20 of the solid-liquid ratio. Under this condition, the extraction rate of citronellol from leaves of Pelargonium graveolens was 0.88 mg/g.

  11. Solid-liquid transition in Nb powder determined by third harmonic susceptibility

    Oliveira, A.A.M. [Grupo de Supercondutividade e Magnetismo, Departamento de Fisica, Universidade Federal de Sao Carlos, Sao Carlos, SP (Brazil)], E-mail:; Lisboa-Filho, P.N. [Laboratorio de Materiais Supercondutores, Departamento de Fisica, Universidade Estadual Paulista, Bauru, SP (Brazil); Ortiz, W.A. [Grupo de Supercondutividade e Magnetismo, Departamento de Fisica, Universidade Federal de Sao Carlos, Sao Carlos, SP (Brazil)


    Measurements of the third harmonic of the AC-susceptibility were employed to determine the boundaries of the linear regime of the magnetic response of Nb powder. Non-linear contributions to the magnetic response reveal the occurrence of a structured phase, disappearing as the vortex lattice melts to the liquid state. A systematic study of the third harmonic was conducted to determine how its onset temperature depends on experimental parameters, such as the frequency and amplitude of the excitation field. The melting line (ML) has been extracted from the onset temperature measured at low-frequencies and low-excitation fields in the presence of DC magnetic fields. The study indicates that the ML can be described by a 3D vortex-glass model, except at lower fields, where the system experiences a depinning crossover, and the best description of the experimental data is provided by a 3D Bose-glass model.

  12. Study of solid/liquid and solid/gas interfaces in Cu–isoleucine complex by surface X-ray diffraction

    Ferrer, Pilar, E-mail: [SpLine Spanish CRG Beamline at the ESRF, 38000 Grenoble (France); Instituto de Ciencia de Materiales de Madrid, 28049 Madrid (Spain); Rubio-Zuazo, Juan; Castro, German R. [SpLine Spanish CRG Beamline at the ESRF, 38000 Grenoble (France); Instituto de Ciencia de Materiales de Madrid, 28049 Madrid (Spain)


    The enzymes could be understood like structures formed by amino acids bonded with metals, which act as active sites. The research on the coordination of metal–amino acid complexes will bring light on the behavior of metal enzymes, due to the close relation existing between the atomic structure and the functionality. The Cu–isoleucine bond is considered as a good model system to attain a better insight into the characteristics of naturally occurring copper metalloproteins. The surface structure of metal–amino acid complex could be considered as a more realistic model for real systems under biologic working conditions, since the molecular packing is decreased. In the surface, the structural constrains are reduced, keeping the structural capability of surface complex to change as a function of the surrounding environment. In this work, we present a surface X-ray diffraction study on Cu–isoleucine complex under different ambient conditions. Cu(Ile){sub 2} crystals of about 5 mm × 5 mm × 1 mm have been growth, by seeding method in a supersaturated solution, presenting a surface of high quality. The sample for the surface diffraction study was mounted on a cell specially designed for solid/liquid or solid/gas interface analysis. The Cu–isoleucine crystal was measured under a protective dry N{sub 2} gas flow and in contact with a saturated metal amino acid solution. The bulk and the surface signals were compared, showing different atomic structures. In both cases, from surface diffraction data, it is observed that the atomic structure of the top layer undergoes a clear structural deformation. A non-uniform surface relaxation is observed producing an inhomogeneous displacement of the surface atoms towards the surface normal.

  13. Study of solid/liquid and solid/gas interfaces in Cu-isoleucine complex by surface X-ray diffraction

    Ferrer, Pilar; Rubio-Zuazo, Juan; Castro, German R.


    The enzymes could be understood like structures formed by amino acids bonded with metals, which act as active sites. The research on the coordination of metal-amino acid complexes will bring light on the behavior of metal enzymes, due to the close relation existing between the atomic structure and the functionality. The Cu-isoleucine bond is considered as a good model system to attain a better insight into the characteristics of naturally occurring copper metalloproteins. The surface structure of metal-amino acid complex could be considered as a more realistic model for real systems under biologic working conditions, since the molecular packing is decreased. In the surface, the structural constrains are reduced, keeping the structural capability of surface complex to change as a function of the surrounding environment. In this work, we present a surface X-ray diffraction study on Cu-isoleucine complex under different ambient conditions. Cu(Ile)2 crystals of about 5 mm × 5 mm × 1 mm have been growth, by seeding method in a supersaturated solution, presenting a surface of high quality. The sample for the surface diffraction study was mounted on a cell specially designed for solid/liquid or solid/gas interface analysis. The Cu-isoleucine crystal was measured under a protective dry N2 gas flow and in contact with a saturated metal amino acid solution. The bulk and the surface signals were compared, showing different atomic structures. In both cases, from surface diffraction data, it is observed that the atomic structure of the top layer undergoes a clear structural deformation. A non-uniform surface relaxation is observed producing an inhomogeneous displacement of the surface atoms towards the surface normal.

  14. CRYOCHEM, Thermodynamic Model for Cryogenic Chemical Systems: Solid-Vapor and Solid-Liquid-Vapor Phase Equilibria Toward Applications on Titan and Pluto

    Tan, S. P.; Kargel, J. S.; Adidharma, H.; Marion, G. M.


    Until in-situ measurements can be made regularly on extraterrestrial bodies, thermodynamic models are the only tools to investigate the properties and behavior of chemical systems on those bodies. The resulting findings are often critical in describing physicochemical processes in the atmosphere, surface, and subsurface in planetary geochemistry and climate studies. The extremely cold conditions on Triton, Pluto and other Kuiper Belt Objects, and Titan introduce huge non-ideality that prevents conventional models from performing adequately. At such conditions, atmospheres as a whole—not components individually—are subject to phase equilibria with their equilibrium solid phases or liquid phases or both. A molecular-based thermodynamic model for cryogenic chemical systems, referred to as CRYOCHEM, the development of which is still in progress, was shown to reproduce the vertical composition profile of Titan's atmospheric methane measured by the Huygens probe (Tan et al., Icarus 2013, 222, 53). Recently, the model was also used to describe Titan's global circulation where the calculated composition of liquid in Ligeia Mare is consistent with the bathymetry and microwave absorption analysis of T91 Cassini fly-by data (Tan et al., 2014, submitted). Its capability to deal with equilibria involving solid phases has also been demonstrated (Tan et al., Fluid Phase Equilib. 2013, 360, 320). With all those previous works done, our attention is now shifting to the lower temperatures in Titan's tropopause and on Pluto's surface, where much technical development remains for CRYOCHEM to assure adequate performance at low temperatures. In these conditions, solid-vapor equilibrium (SVE) is the dominant phase behavior that determines the composition of the atmosphere and the existing ices. Another potential application is for the subsurface phase equilibrium, which also involves liquid, thus three-phase equilibrium: solid-liquid-vapor (SLV). This presentation will discuss the

  15. Rapid automatic keyword extraction for information retrieval and analysis

    Rose, Stuart J [Richland, WA; Cowley,; E, Wendy [Richland, WA; Crow, Vernon L [Richland, WA; Cramer, Nicholas O [Richland, WA


    Methods and systems for rapid automatic keyword extraction for information retrieval and analysis. Embodiments can include parsing words in an individual document by delimiters, stop words, or both in order to identify candidate keywords. Word scores for each word within the candidate keywords are then calculated based on a function of co-occurrence degree, co-occurrence frequency, or both. Based on a function of the word scores for words within the candidate keyword, a keyword score is calculated for each of the candidate keywords. A portion of the candidate keywords are then extracted as keywords based, at least in part, on the candidate keywords having the highest keyword scores.

  16. Design and Implementation of SMS Extraction and Analysis System

    Wan Yu-Yang


    Full Text Available With more and more applications of smart phone, more and more text messages in mobile phone, and then more and more information possibly contained in text messages. How to dig out useful information form SMS? This paper discusses techniques of the SMS extraction and analysis. Taking the bank SMS as example, key information is extracted to inform, is formatted to story in APP database, and then be analysed and statistic result shown in chart. The APP with the function is run well on Android phone and has Practical value. This technology helps to expand the application of SMS.

  17. Features extraction in anterior and posterior cruciate ligaments analysis.

    Zarychta, P


    The main aim of this research is finding the feature vectors of the anterior and posterior cruciate ligaments (ACL and PCL). These feature vectors have to clearly define the ligaments structure and make it easier to diagnose them. Extraction of feature vectors is obtained by analysis of both anterior and posterior cruciate ligaments. This procedure is performed after the extraction process of both ligaments. In the first stage in order to reduce the area of analysis a region of interest including cruciate ligaments (CL) is outlined in order to reduce the area of analysis. In this case, the fuzzy C-means algorithm with median modification helping to reduce blurred edges has been implemented. After finding the region of interest (ROI), the fuzzy connectedness procedure is performed. This procedure permits to extract the anterior and posterior cruciate ligament structures. In the last stage, on the basis of the extracted anterior and posterior cruciate ligament structures, 3-dimensional models of the anterior and posterior cruciate ligament are built and the feature vectors created. This methodology has been implemented in MATLAB and tested on clinical T1-weighted magnetic resonance imaging (MRI) slices of the knee joint. The 3D display is based on the Visualization Toolkit (VTK).

  18. Evolution of Analysis of Polyhenols from Grapes, Wines, and Extracts

    Pierre-Louis Teissedre


    Full Text Available Grape and wine phenolics are structurally diverse, from simple molecules to oligomers and polymers usually designated as tannins. They have an important impact on the organoleptic properties of wines, that’s why their analysis and quantification are of primordial importance. The extraction of phenolics from grapes and from wines is the first step involved in the analysis. Then, several analytical methods have been developed for the determination of total content of phenolic, while chromatographic and spectrophotometric analyses are continuously improved in order to achieve adequate separation of phenolic molecules, their subsequent identification and quantification. This review provides a summary of evolution of analysis of polyphenols from grapes, wines and extracts.

  19. Social network extraction and analysis based on multimodal dyadic interaction.

    Escalera, Sergio; Baró, Xavier; Vitrià, Jordi; Radeva, Petia; Raducanu, Bogdan


    Social interactions are a very important component in people's lives. Social network analysis has become a common technique used to model and quantify the properties of social interactions. In this paper, we propose an integrated framework to explore the characteristics of a social network extracted from multimodal dyadic interactions. For our study, we used a set of videos belonging to New York Times' Blogging Heads opinion blog. The Social Network is represented as an oriented graph, whose directed links are determined by the Influence Model. The links' weights are a measure of the "influence" a person has over the other. The states of the Influence Model encode automatically extracted audio/visual features from our videos using state-of-the art algorithms. Our results are reported in terms of accuracy of audio/visual data fusion for speaker segmentation and centrality measures used to characterize the extracted social network.

  20. Social Network Extraction and Analysis Based on Multimodal Dyadic Interaction

    Bogdan Raducanu


    Full Text Available Social interactions are a very important component in people’s lives. Social network analysis has become a common technique used to model and quantify the properties of social interactions. In this paper, we propose an integrated framework to explore the characteristics of a social network extracted from multimodal dyadic interactions. For our study, we used a set of videos belonging to New York Times’ Blogging Heads opinion blog. The Social Network is represented as an oriented graph, whose directed links are determined by the Influence Model. The links’ weights are a measure of the “influence” a person has over the other. The states of the Influence Model encode automatically extracted audio/visual features from our videos using state-of-the art algorithms. Our results are reported in terms of accuracy of audio/visual data fusion for speaker segmentation and centrality measures used to characterize the extracted social network.

  1. Microscale extraction method for HPLC carotenoid analysis in vegetable matrices

    Sidney Pacheco


    Full Text Available In order to generate simple, efficient analytical methods that are also fast, clean, and economical, and are capable of producing reliable results for a large number of samples, a micro scale extraction method for analysis of carotenoids in vegetable matrices was developed. The efficiency of this adapted method was checked by comparing the results obtained from vegetable matrices, based on extraction equivalence, time required and reagents. Six matrices were used: tomato (Solanum lycopersicum L., carrot (Daucus carota L., sweet potato with orange pulp (Ipomoea batatas (L. Lam., pumpkin (Cucurbita moschata Duch., watermelon (Citrullus lanatus (Thunb. Matsum. & Nakai and sweet potato (Ipomoea batatas (L. Lam. flour. Quantification of the total carotenoids was made by spectrophotometry. Quantification and determination of carotenoid profiles were formulated by High Performance Liquid Chromatography with photodiode array detection. Microscale extraction was faster, cheaper and cleaner than the commonly used one, and advantageous for analytical laboratories.

  2. Molecularly Imprinted Polymers for Ochratoxin A Extraction and Analysis

    Jorn C. C. Yu


    Full Text Available Molecularly imprinted polymers (MIPs are considered as polymeric materials that mimic the functionality of antibodies. MIPs have been utilized for a wide variety of applications in chromatography, solid phase extraction, immunoassays, and sensor recognition. In this article, recent advances of MIPs for the extraction and analysis of ochratoxins are discussed. Selection of functional monomers to bind ochratoxin A (OTA with high affinities, optimization of extraction procedures, and limitations of MIPs are compared from different reports. The most relevant examples in the literature are described to clearly show how useful these materials are. Strategies on MIP preparation and schemes of analytical methods are also reviewed in order to suggest the next step that would make better use of MIPs in the field of ochratoxin research. The review ends by outlining the remaining issues and impediments.

  3. Development of sample preparation method for eleutheroside B and E analysis in Acanthopanax senticosus by ionic liquids-ultrasound based extraction and high-performance liquid chromatography detection.

    Yang, Lei; Ge, Hongshuang; Wang, Wenjie; Zu, Yuangang; Yang, Fengjian; Zhao, Chunjian; Zhang, Lin; Zhang, Ying


    An ionic liquids-based ultrasonic-assisted extraction (ILUAE) method was successfully developed for extracting eleutheroside B and E from Radix Acanthopanax senticosus. Thirteen 1-alkyl-3-methylimidazolium ionic liquids with different cations and anions were investigated and 1-butyl-3-methylimidazolium bromide ([C4mim]Br) solution was selected as the solvent. The conditions for ILUAE, including the ionic liquid concentration, soaking time, ultrasonic power, ultrasonic time, solid-liquid ratio and number of extraction cycles, were optimized. With the proposed method, the energy consumption time was reduced to 30 min, whereas conventional method requires about 4h. The proposed method had good recovery (97.96-103.39%) and reproducibility (RSD, n=5; 3.3% for eleutheroside B, 4.6% for eleutheroside E). ILUAE was an efficient, rapid and simple sample preparation technique that showed high reproducibility and was environmental friendly.

  4. Micro-solid-phase extraction coupled to desorption electrospray ionization-high-resolution mass spectrometry for the analysis of explosives in soil.

    Bianchi, Federica; Gregori, Adolfo; Braun, Gabriele; Crescenzi, Carlo; Careri, Maria


    Home-made micro-solid-phase extraction (SPE) cartridges using different adsorbent materials were tested for the desorption electrospray ionization-high-resolution mass spectrometry (DESI-HRMS) determination of explosives like 2,4,6-trinitrotoluene, cyclotrimethylene-trinitramine, cyclotetramethylene-tetranitramine, pentaerythritol tetranitrate, and trinitrophenylmethylnitramine in soil samples. Quantitation limits in the low nanogram per kilogram range proved the reliability of the method for the detection of explosives at ultra-trace levels. The reduced sample preparation allowed for low costs and high-throughput analyses. Finally, the superior extraction capability of the method was proved by obtaining DESI-HRMS responses at least five times higher than those achieved by performing DESI-HRMS analyses of solid-liquid extracts spotted onto commercial polytetrafluoroethylene slides.

  5. Measurement of Peltier Heat at the Solid/Liquid Interface and Its Application to Crystal Growth II : Measurement and Application

    Kim, I.H. [Chungju National University, Chungju (Korea); Jang, K.W. [Hanseo University, Seosan (Korea); Lee, D.H. [Yonsei University, Seoul (Korea)


    Thermoelectric effects on the temperature changes at the solid- and liquid-phase and its interface were studied by using the unidirectional solidification of Bi{sub 2}Te{sub 3}. Cooling or heating effects measured with current density, polarity and current passing time were quite different. By separating sole Peltier, Thomson and Joule heat theoretically and experimentally, the Peltier coefficient at the solid/liquid interface of Bi{sub 2}Te{sub 3} was -1.10 X 10{sup -1} V, and the Thomson coefficients of solid- and liquid-phase were 7.31 X 10{sup -4} V/K, 5.77 X 10{sup -5}V/K, respectively. When D.C. passed from solid-phase to liquid-phase during the crystal growth of Bi{sub 2}Te{sub 3}, the crystal with more directionality was obtained owing to increase of the temperature gradient in liquid by the Peltier cooling. But in reverse current direction, the crystallinity was not changed significantly. (author). 10 refs., 7 figs., 1 tab.

  6. The solid-liquid phase diagrams of binary mixtures of even saturated fatty acids differing by six carbon atoms

    Costa, Mariana C. [LPT, Department of Chemical Process, School of Chemical Engineering, University of Campinas, UNICAMP, P.O. Box 6066, 13083-970, Campinas-SP (Brazil); EXTRAE, Department of Food Engineering, Faculty of Food Engineering, University of Campinas, UNICAMP, P.O. Box 6121, 13083-862, Campinas-SP (Brazil); CICECO, Departamento de Quimica da Universidade de Aveiro, 3810-193 Aveiro (Portugal); Rolemberg, Marlus P. [DETQI, Department of Chemical Technology, Federal University of Maranhao (UFMA), Sao Luis, Maranhao (Brazil); Meirelles, Antonio J.A. [EXTRAE, Department of Food Engineering, Faculty of Food Engineering, University of Campinas, UNICAMP, P.O. Box 6121, 13083-862, Campinas-SP (Brazil); Coutinho, Joao A.P. [CICECO, Departamento de Quimica da Universidade de Aveiro, 3810-193 Aveiro (Portugal); Kraehenbuehl, M.A., E-mail: [LPT, Department of Chemical Process, School of Chemical Engineering, University of Campinas, UNICAMP, P.O. Box 6066, 13083-970, Campinas-SP (Brazil)


    This study was aimed at using the solid-liquid phase diagrams for three binary mixtures of saturated fatty acids, especially the phase transitions below the liquidus line. These mixtures are compounded by caprylic acid (C{sub 8:0}) + myristic acid (C{sub 14:0}), capric acid (C{sub 10:0}) + palmitic acid (C{sub 16:0}), lauric acid (C{sub 12:0}) + stearic acid (C{sub 18:0}), differing by six carbon atoms between carbon chains. The phase diagrams were obtained by differential scanning calorimetry (DSC). The polarized light microscopy was used to complement the characterization for a full grasp of the phase diagram. Not only do these phase diagrams present peritectic and eutectic reactions, but also metatectic reactions, due to solid-solid phase transitions common, in fatty acids. These findings have contributed to the elucidation of the phase behavior of these important biochemical molecules with implications in various industrial production.

  7. Heterogeneous nucleation of calcium phosphate salts at a solid/liquid interface examined by scanning angle reflectometry

    Ngankam, P. A.; Schaaf, P.; Voegel, J. C.; Cuisinier, F. J. G.


    Mineralization of calcium phosphate salts at a solid/liquid silica interface was examined by means of scanning angle reflectometry (SAR). A critical supersaturation of 7.60±0.15 mM was found to be the lowest calcium phosphate concentration at pH 6.85 at which the reflectivity at the Brewster angle started to vary. The analyses of the signals by mean of the homogeneous isotropic layer model led to layer thicknesses of about 3.5 μm also characterized by very low mean refractive index increments. These observations were completed by complementary experiments. Scanning and transmission electron microscopy led to similar layer thicknesses with crystallites dispersed in the whole layer confirming thus SAR results. X-ray analyses showed a presence of brushite (DCPD) at the silica interface. A pH of 5.44 was estimated for the acidic silica interface for which DCPD is nucleated after addition of 7.60±0.15 mM calcium and phosphate. However, at this pH value, the solution is largely supersaturated with respect to hydroxyapatite (HAP theoretical saturating concentration: 1.37 mM). A faster growth of DCPD crystals compared to HAP crystals is thus assumed to explain our observations.

  8. Anisotropy of the solid-liquid interface properties of the Ni-Zr B33 phase from molecular dynamics simulation

    Wilson, S. R.; Mendelev, M. I.


    Solid-liquid interface (SLI) properties of the Ni-Zr B33 phase were determined from molecular dynamics simulations. In order to perform these measurements, a new semi-empirical potential for Ni-Zr alloy was developed that well reproduces the material properties required to model SLIs in the Ni50.0Zr50.0 alloy. In particular, the developed potential is shown to provide that the solid phase emerging from the liquid Ni50.0Zr50.0 alloy is B33 (apart from a small fraction of point defects), in agreement with the experimental phase diagram. The SLI properties obtained using the developed potential exhibit an extraordinary degree of anisotropy. It is observed that anisotropies in both the interfacial free energy and mobility are an order of magnitude larger than those measured to date in any other metallic compound. Moreover, the [0 1 0] interface is shown to play a significant role in the observed anisotropy. Our data suggest that the [0 1 0] interface simultaneously corresponds to the lowest mobility, the lowest free energy and the highest stiffness of all inclinations in B33 Ni-Zr. This finding can be understood by taking into account a rather complicated crystal structure in this crystallographic direction.

  9. Numerical simulation of predicting and reducing solid particle erosion of solid-liquid two-phase flow in a choke

    Li Guomei; Wang Yueshe; He Renyang; Cao Xuewen; Lin Changzhi; Meng Tao


    Chokes are one of the most important components of downhole flow-control equipment. The particle erosion mathematical model, which considers particle-particle interaction, was established and used to simulate solid particle movement as well as particle erosion characteristics of the solid-liquid two-phase flow in a choke. The corresponding erosion reduction approach by setting ribs on the inner wall of the choke was advanced. This mathematical model includes three parts: the flow field simulation of the continuous carrier fluid by an Eulerian approach, the particle interaction simulation using the discrete particle hard sphere model by a Lagrangian approach and calculation of erosion rate using semi-empirical correlations. The results show that particles accumulated in a narrow region from inlet to outlet of the choke and the dominating factor affecting particle motion is the fluid drag force. As a result, the optimization of rib geometrical parameters indicates that good anti-erosion performance can be achieved by four ribs, each of them with a height (H) of 3 mm and a width (B) of 5 mm equaling the interval between ribs (L).

  10. Experimental study of the solid-liquid interface in a yield-stress fluid flow upstream of a step

    Luu, Li-Hua; Pierre, Philippe; Guillaume, Chambon


    We present an experimental study where a yield-stress fluid is implemented to carefully examine the interface between a liquid-like unyielded region and a solid-like yielded region. The studied hydrodynamics consists of a rectangular pipe-flow disturbed by the presence of a step. Upstream of the step, a solid-liquid interface between a dead zone and a flow zone appears. This configuration can both model geophysical erosion phenomenon in debris flows or find applications for industrial extrusion processes. We aim to investigate the dominant physical mechanism underlying the formation of the static domain, by combining the rheological characterization of the yield-stress fluid with local measurements of the related hydrodynamic parameters. In this work, we use a model fluid, namely polymer micro-gel Carbopol, that exhibits a Hershel-Bulkley viscoplastic rheology. Exploiting the fluid transparency, the flow is monitored by Particle Image Velocimetry thanks to internal visualization technique. In particular, we demonstrate that the flow above the dead zone roughly behaves as a plug flow whose velocity profile can successfully be described by a Poiseuille equation including a Hershel-Bulkley rheology (PHB theory), with exception of a thin zone at the close vicinity of the static domain. The border inside the flow zone above which the so-called PHB flow starts, is found to be the same regardless of the flow rate and to move with a constant velocity that increases with the flow rate. We interpret this feature as a slip frontier.

  11. Batch and semi-continuous anaerobic digestion of food waste in a dual solid-liquid system.

    Zhang, Cunsheng; Su, Haijia; Tan, Tianwei


    To avoid the inhibition from both of waste oil and high concentrations of cationic elements, anaerobic digestion of food waste in a dual solid-liquid (ADSL) system was examined in this present paper. Results from batch test indicated that a higher methane yield could be obtained in the ADSL system. The methane yield of food solid waste (FSW), food liquid waste (FLW) and raw food waste (RFW) were 643, 659 and 581 mL/g-VS, respectively. In semi-continuous anaerobic digestion, the optimum organic loading rates (OLR) for FSW, FLW and RFW were 9, 4 and 7 g-VS/L/d, respectively. The total methane production of RFW and ADSL systems, based on 1 kg-VS(RFW), were 405 and 460 L, respectively, indicating that the methane production increased by 13.6% in the ADSL system. The optimum C/N ratio, redistribution of metal element and lower content of waste oil in FSW explain the higher methane production.

  12. The solid-liquid phase diagrams of binary mixtures of consecutive, even saturated fatty acids: differing by four carbon atoms.

    Costa, Mariana C; Sardo, Mariana; Rolemberg, Marlus P; Ribeiro-Claro, Paulo; Meirelles, Antonio J A; Coutinho, João A P; Krähenbühl, M A


    The complete solid-liquid phase diagrams for four binary mixtures of saturated fatty acids are presented, for the first time, in this work. These mixtures are formed by caprylic acid (C(8:0))+lauric acid (C(12:0)), capric acid (C(10:0))+myristic acid (C(14:0)), lauric acid (C(12:0))+palmitic acid (C(16:0)) and myristic acid (C(14:0))+stearic acid (C(18:0)). The phase diagrams were obtained by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). FT-Raman spectrometry and polarized light microscopy were used to complement the characterization for a complete understanding of the phase diagram. All of the phase diagrams here reported show the same global behavior that is far more complex than previously accepted. They present not only peritectic and eutectic reactions, but also metatectic reactions, due to solid-solid phase transitions common in fatty acids, and regions of solid solution not previously reported. This work contributes to the elucidation of the phase behavior of these important biochemical molecules with implications in various industrial applications.

  13. Solid-Liquid State Bonding of Si3N4 Ceramics with Ceramic-Modified Brazing Alloy

    杨俊; 吴爱萍; 邹贵生; 张德库; 刘根茂


    Solid-liquid state bonding of Si3N4 ceramics with TiN-modified Ag-Cu-Ti brazing alloy was used to enhance joint strength. The effects of the TiN particles on the microstructures, interfacial reactions, and room-temperature properties of the joints were investigated. The results show that the TiN particles are generally well dispersed in the Ag-Cu eutectic base and the interface between them is both clean and compact. Changes in the TiN volume fractions from 0 to 20% exert no noticeable effect on the interfacial reaction between Ag-Cu-Ti and the substrates. Other bonding parameters being constant, the TiN volume fraction in the filler material plays a key role in the joint properties. For TiN volume fractions below 20%, the joints are reinforced, especially joints with 5% and 20% TiN. The average shearing strength of joints with 5%TiN is 200.8 MPa, 30% higher than that of joints with no TiN (154.1 MPa). However, for TiN volumes fractions above 20%, the joint strengths decrease.

  14. On a phase field model for solid-liquid phase transitions

    Benzoni-Gavage, Sylvie; Jamet, Didier; Vovelle, Julien


    A new phase field model is introduced, which can be viewed as nontrivial generalisation of what is known as the Caginalp model. It involves in particular nonlinear diffusion terms. By formal asymptotic analysis, it is shown that in the sharp interface limit it still yields a Stefan-like model with: 1) a (generalized) Gibbs-Thomson relation telling how much the interface temperature differs from the equilibrium temperature when the interface is moving or/and is curved with surface tension; 2) a jump condition for the heat flux, which turns out to depend on the latent heat and on the velocity of the interface with a new, nonlinear term compared to standard models. From the PDE analysis point of view, the initial-boundary value problem is proved to be locally well-posed in time (for smooth data).

  15. Ground extraction from airborne laser data based on wavelet analysis

    Xu, Liang; Yang, Yan; Jiang, Bowen; Li, Jia


    With the advantages of high resolution and accuracy, airborne laser scanning data are widely used in topographic mapping. In order to generate a DTM, measurements from object features such as buildings, vehicles and vegetation have to be classified and removed. However, the automatic extraction of bare earth from point clouds acquired by airborne laser scanning equipment remains a problem in LIDAR data filtering nowadays. In this paper, a filter algorithm based on wavelet analysis is proposed. Relying on the capability of detecting discontinuities of continuous wavelet transform and the feature of multi-resolution analysis, the object points can be removed, while ground data are preserved. In order to evaluate the performance of this approach, we applied it to the data set used in the ISPRS filter test in 2003. 15 samples have been tested by the proposed approach. Results showed that it filtered most of the objects like vegetation and buildings, and extracted a well defined ground model.

  16. Quantitative and qualitative validations of a sonication-based DNA extraction approach for PCR-based molecular biological analyses.

    Dai, Xiaohu; Chen, Sisi; Li, Ning; Yan, Han


    The aim of this study was to comprehensively validate the sonication-based DNA extraction method, in hope of the replacement of the so-called 'standard DNA extraction method' - the commercial kit method. Microbial cells in the digested sludge sample, containing relatively high amount of PCR-inhibitory substances, such as humic acid and protein, were applied as the experimental alternatives. The procedure involving solid/liquid separation of sludge sample and dilution of both DNA templates and inhibitors, the minimum templates for PCR-based analyses, and the in-depth understanding from the bias analysis by pyrosequencing technology were obtained and confirmed the availability of the sonication-based DNA extraction method. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. 高分子在固液界面吸附构象的研究方法及手段%Methods and Techniques for Studying the Adsorption Conformation of Polymers at Solid/Liquid Interface

    李海普; 李星; 张莎莎; 钟志辉


    The characterization of the adsorption conformation of polymers at solid/liquid interlace is one of the important topics for the functionality and application of the polymers, which has attracted more interests.Due to the complexity of adsorption conformation, it becomes a delicate issue to select the suitable means or methods.The influenee factors on polymer conformation were briefly introduced.The methods and techniques used for characterizing of the adsorption conformation of polymers at solid/liquid interface were discussed from the view points of instrumental analysis.%高分子在固液界面的构象表征对其功能实现及实际应用具有重要意义,是高分子研究领域的热点之一.由于高分子吸附构象的复杂性及其影响因素的多样性,选择合适的方法及手段成为表征的关键.本文简单介绍了影响高分子构象的一些因素,并从仪器分析的角度出发,根据研究目的综述了高分子与固体表面的键合方式、在固液界面的吸附方式、吸附行为及吸附层微观结构的研究方法和手段.

  18. Blind Extraction and Security Analysis of Spread Spectrum Hidden Watermarks


    DATES COVERED (From - To) JAN 2009 – DEC 2010 4. TITLE AND SUBTITLE BLIND EXTRACTION AND SECURITY ANALYSIS OF SPREAD SPECTRUM HIDDEN WATERMARKS ...Multi Signature Embedding, Watermarking , DSSS. 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18. NUMBER OF PAGES 15 19a... watermarks John A. Marsh*a,b, and Gerard F. Wohlrabc aSUNY Institute of Technology, 100 Seymour Dr., Utica, NY 13502; bAssured Information

  19. Polysaccharides in Sipunculus nudus: Extraction condition optimization and antioxidant activities

    Zhang, Qin; Dong, Lanfang; Tong, Tong; Wang, Qingchao; Xu, Mingzhu


    Marine organisms constitute unlimited resource of bioactive substances due to their high biodiversity and represent a valuable source of new compounds. This study optimized the alkali-extraction conditions and antioxidant activities of soluble polysaccharides from the body wall of Sipunculus nudus. The effects of solid-liquid ratio, extraction duration, extraction temperature, and alkali concentration on the yield of S. nudus polysaccharides (SNP) were examined, according to which the optimal combination of extraction parameters was obtained by an orthogonal test. The relative influencing importance of different extraction parameters on the yield of SNP followed the order as solid-liquid ratio > extraction temperature > alkali concentration > extraction duration. The highest extraction yield, 1.98%, was achieved under an optimal extraction condition: temperature 60°C, solid-liquid ratio 1:6 g mL-1, duration 5 h, and alkali (NaOH) mass fraction 6%. The in vitro antioxidant activities examination showed that extracted SNP under this optimized condition had strong power in reducing certain hydroxyl and superoxide radical scavenging abilities. The promising results showed that extracted SNP could be a potent natural antioxidant.

  20. Solid-liquid adsorption of calcium phosphate on TiO{sub 2}

    Chusuei, C.C.; Goodman, D.W.; Stipdonk, M.J. van; Justes, D.R.; Loh, K.H.; Schweikert, E.A.


    Calcium phosphate (CP) in aqueous solution was exposed to thin-film TiO{sub 2} surfaces at predetermined times ranging from 10 min to 20 h using a liquid reaction apparatus (LRA). Surface analysis was then performed using X-ray photoelectron (XPS) and Auger electron (AES) spectroscopies and time-of-flight secondary ion mass spectromemtry (ToF-SIMS) with polyatomic primary ions. XPS revealed that CP nucleated and grew on the TiO{sub 2} surface, with phosphate groups growing on top of an initial 2-dimensional (2D) Ca-rich layer. AES depth profiling of a 4-h solution exposure complemented this finding and gave additional evidence for 3-dimensional (3D) phosphate islands forming on top of the calcium. ToF-SIMS analysis of CP adsorbed on the surface indicated that the predominant phase on the surface was brushite, CaHPO{sub 4}{sm{underscore}bullet}2H{sub 2}O. A model for Ca{sup 2+} cation bridging at the oxide interface is proposed.

  1. Molecular dynamics analysis of the friction between a water-methanol liquid mixture and a non-polar solid crystal surface

    Nakaoka, Satoshi; Yamaguchi, Yasutaka; Omori, Takeshi; Joly, Laurent


    We performed molecular dynamics analysis of the momentum transfer at the solid-liquid interface for a water-methanol liquid mixture between parallel non-polar solid walls in order to understand the strong decrease of the friction coefficient (FC) induced by the methanol adsorption at the surface observed in our previous work [S. Nakaoka et al., Phys. Rev. E 92, 022402 (2015)]. In particular, we extracted the individual contributions of water and methanol molecules to the total FC and found that the molecular FC for methanol was larger than that for water. We further showed that the reduction of the total solid-liquid FC upon the increase of the methanol molar fraction in the first adsorption layer occurred as a result of a decrease in the molecular number density as well as a decrease in the molecular FCs of both molecules. Analysis of the molecular orientation revealed that the decrease of the molecular FC of methanol resulted from changes of the contact feature onto the solid surface. Specifically, methanol molecules near the solid surface had their C-O bond parallel to the surface with both CH3 and O sites contacting the solid at low methanol molar fraction, while they had their C-O bond outward from the surface with only the CH3 site contacting the solid at higher methanol molar fraction. The mechanisms discussed in this work could be used to search for alternative water additives to further reduce the solid-liquid friction.

  2. Morphologies of solid-liquid interface and surface steps during rapid growth of BaB2O4 single crystals


    The evolution of solid-liquid interface during BBO single crystal growth was stud- ied by the differential interference microscopy. And the step morphology on (0001) surface of the as-grown crystal was observed by the atomic force microscopy as well. It was found that the transition from a flat solid-liquid interface to a skeletal shape will occur in case of rapid growth. However, AFM images of surface steps revealed morphology differences correlated with crystallographic directions. The steps advancing along <1010 > direction form the step flow, whereas those steps propagating along <0110 > direction shape into step segments. Measurements of step heights by AFM indicated that it is the high anisotropy of the dimension of growth unit and step bunching due to the enlargement of concentration difference along the surface that results in the anisotropy of step morphologies.

  3. Morphologies of solid-liquid interface and surface steps during rapid growth of BaB2O4 single crystals

    PAN XiuHong; AI Fei; JIN WeiQing; LIU Yan; ZHANG Ying


    The evolution of solid-liquid interface during BBO single crystal growth was studied by the differential interference microscopy. And the step morphology on (0001) surface of the as-grown crystal was observed by the atomic force microscopy as well. It was found that the transition from a flat solid-liquid interface to a skeletal shape will occur in case of rapid growth. However, AFM images of surface steps revealed morphology differences correlated with crystallographic directions. The steps advancing along direction form the step flow, whereas those steps propagating along direction shape into step segments. Measurements of step heights by AFM indicated that it is the high anisotropy of the dimension of growth unit and step bunching due to the enlargement of concentration difference along the surface that results in the anisotropy of step morphologies.

  4. Thermodynamic study of binary system Propafenone Hydrocloride with Metoprolol Tartrate: solid-liquid equilibrium and compatibility with α-lactose monohydrate and corn starch.

    Marinescu, Daniela-Crina; Pincu, Elena; Meltzer, Viorica


    Solid-liquid equilibrium (SLE) for binary mixture of Propafenone Hydrocloride (PP) with Metoprolol Tartrate (MT) was investigated using differential scanning calorimetry (DSC) and corresponding activity coefficients were calculated. Simple eutectic behavior for this system was observed. The excess thermodynamic functions: G(E) and S(E) for the pre-, post-, and eutectic composition have been obtained using the computed activity coefficients data of the eutectic phase with their excess chemical potentials μi(E) (i=1, 2). The experimental solid-liquid phase temperatures were compared with predictions obtained from available eutectic equilibrium models. The results indicate non-ideality in this mixture. Also, the compatibility of each component and their eutectic mixture with usual excipients was investigated, and the DSC experiments indicate possible weak interactions with α-lactose monohydrate and compatibility with corn starch. The results obtained were confirmed by FT-IR measurements.

  5. User Suggestions Extraction from customer Reviews A Sentiment Analysis approach



    Full Text Available Customer review is a major criterion for the improvement of the quality of services rendered and enhancement of the deliverables. Blogs, articles and discussion forums, provide manufacturers or sellers with a good understanding of the reception level of their products in the competitive market. An interesting area from the business analysis perspective, this paper discusses an opinion based mining technique for the extraction of the relevant data using Natural Language Processing and text analysis, and comprehends suggestions from an actionable feedback.

  6. Theory of Brushes Formed by Ψ-Shaped Macromolecules at Solid-Liquid Interfaces.

    Zhulina, Ekaterina B; Leermakers, Frans A M; Borisov, Oleg V


    We present a theoretical analysis targeted to describe the structural properties of brushes formed by Ψ-shaped macromolecules tethered by terminal segment of stem to planar surface while exposing multiple free branches to the surrounding solution. We use an analytical self-consistent field approach based on the strong stretching approximation, and the assumption of Gaussian elasticity for linear chain fragments of the tethered macromolecules. The effect of weak and strong polydispersity of branches is analyzed. In the case of weakly polydisperse macromolecules, variations in length of branches lead to a more uniform polymer density distribution with slight increase in the brush thickness compared to the case of monodisperse chains with the same degree of polymerization. We demonstrate that in contrast to linear chains, strong polydispersity of Ψ-shaped macromolecules does not necessarily lead to strong perturbations in polymer density distribution. In particular, mixed brushes of the so-called "mirror" dendrons (in which number of stem monomers in one component coincides with number of monomers in a branch of the other component, and vice versa) give rise to a unified polymer density distribution with shape independent of the brush composition. The predictions of analytical theory are systematically compared to the results of numerical self-consistent field modeling based on the Scheutjens-Fleer approach.

  7. Use of sol-gel systems for solid/liquid separation.

    Chaiko, D. J.; Kopasz, J. P.; Elison, A. J. G.; Chemical Engineering


    A unique approach using sol-gel technology is presented for separating and recovering particulates and colloids from caustic waste slurries. The approach involves the addition of an alkali silicate and an organic gelling agent directly to the waste stream to immobilize particulates that range from macro sizes to submicron colloids. The particulates and colloids become trapped within a silica network that remains porous during the early stages of the sol-gel process. The freshly gelled monolith undergoes a process of syneresis, whereby the water and soluble salts are ejected from the monolith as it contracts. The approach has been illustrated by removal of ultrafine particulates from a Hanford Tank Waste simulant. Initial laboratory tests have shown that it is possible to produce silica monoliths in the presence of 4 M hydroxide. Analysis of the mother liquor produced during syneresis indicated quantitative recovery of the particulates within the monolith. The partitioning of ions between the silica gel and the mother liquor during syneresis correlates directly with the lyotropic series. Salt recoveries from the mother liquor in excess of 90% can be achieved. With a capability of recovering >99.999% of all particulates, including colloids, the process is more efficient than membrane filtration. This approach produces a rock-hard silica monolith that can be used directly as a feedstock to a glass melter or can be consolidated to near theoretical density by sintering.

  8. Mathematical model to analyze the dissolution behavior of metastable crystals or amorphous drug accompanied with a solid-liquid interface reaction.

    Hirai, Daiki; Iwao, Yasunori; Kimura, Shin-Ichiro; Noguchi, Shuji; Itai, Shigeru


    Metastable crystals and the amorphous state of poorly water-soluble drugs in solid dispersions (SDs), are subject to a solid-liquid interface reaction upon exposure to a solvent. The dissolution behavior during the solid-liquid interface reaction often shows that the concentration of drugs is supersaturated, with a high initial drug concentration compared with the solubility of stable crystals but finally approaching the latter solubility with time. However, a method for measuring the precipitation rate of stable crystals and/or the potential solubility of metastable crystals or amorphous drugs has not been established. In this study, a novel mathematical model that can represent the dissolution behavior of the solid-liquid interface reaction for metastable crystals or amorphous drug was developed and its validity was evaluated. The theory for this model was based on the Noyes-Whitney equation and assumes that the precipitation of stable crystals at the solid-liquid interface occurs through a first-order reaction. Moreover, two models were developed, one assuming that the surface area of the drug remains constant because of the presence of excess drug in the bulk and the other that the surface area changes in time-dependency because of agglomeration of the drug. SDs of Ibuprofen (IB)/polyvinylpyrrolidone (PVP) were prepared and their dissolution behaviors under non-sink conditions were fitted by the models to evaluate improvements in solubility. The model assuming time-dependent surface area showed good agreement with experimental values. Furthermore, by applying the model to the dissolution profile, parameters such as the precipitation rate and the potential solubility of the amorphous drug were successfully calculated. In addition, it was shown that the improvement in solubility with supersaturation was able to be evaluated quantitatively using this model. Therefore, this mathematical model would be a useful tool to quantitatively determine the supersaturation

  9. Adsorption at the solid-liquid interface as the source of contact angle dependence on the curvature of the three-phase line.

    Ward, C A; Sefiane, K


    We review the thermodynamic approach to determining the surface tension of solid-fluid interfaces. If the pressure is in the narrow range where the contact angle, θ, can exist, then for isothermal systems, adsorption at the solid-liquid interface affects γ(SL) or θ, but γ(SV) is very nearly equal γ(LV), the surface tension of the adsorbing fluid. For a liquid partially filling a cylinder, the pressure in the liquid phase at the three-phase line, x(3)(L), depends on the curvature of the three-phase line, C(cl), but the line tension can play no role, since it acts perpendicular to the cylinder wall. C(cl) is decreased as the cylinder diameter is increased; x(3)(L) is increased; and θ increases. For a given value of C(cl), x(3)(L) can be changed by rotating the cylinder or by changing the height of the three-phase line in a gravitational field. In all cases, for water in borosilicate glass cylinders, the value of θ is shown to increase as x(3)(L) is increased. This behaviour requires the Gibbsian adsorption at the solid-liquid interface to be negative, indicating the liquid concentration in the interphase is less than that in the bulk liquid. For sessile droplets, the value of θ depends on both x(3)(L) and C(cl). If the value of θ for spherical sessile droplets is measured as a function of C(cl), the adsorption at the solid-liquid interface that would give that dependence can be determined. It is unnecessary to introduce the line tension hypothesis to explain the dependence of θ on C(cl). Adsorption at the solid-liquid interface gives a full explanation.

  10. Enthalpy-based multiple-relaxation-time lattice Boltzmann method for solid-liquid phase-change heat transfer in metal foams

    Liu, Qing; He, Ya-Ling; Li, Qing


    In this paper, an enthalpy-based multiple-relaxation-time (MRT) lattice Boltzmann (LB) method is developed for solid-liquid phase-change heat transfer in metal foams under the local thermal nonequilibrium (LTNE) condition. The enthalpy-based MRT-LB method consists of three different MRT-LB models: one for flow field based on the generalized non-Darcy model, and the other two for phase-change material (PCM) and metal-foam temperature fields described by the LTNE model. The moving solid-liquid phase interface is implicitly tracked through the liquid fraction, which is simultaneously obtained when the energy equations of PCM and metal foam are solved. The present method has several distinctive features. First, as compared with previous studies, the present method avoids the iteration procedure; thus it retains the inherent merits of the standard LB method and is superior to the iteration method in terms of accuracy and computational efficiency. Second, a volumetric LB scheme instead of the bounce-back scheme is employed to realize the no-slip velocity condition in the interface and solid phase regions, which is consistent with the actual situation. Last but not least, the MRT collision model is employed, and with additional degrees of freedom, it has the ability to reduce the numerical diffusion across the phase interface induced by solid-liquid phase change. Numerical tests demonstrate that the present method can serve as an accurate and efficient numerical tool for studying metal-foam enhanced solid-liquid phase-change heat transfer in latent heat storage. Finally, comparisons and discussions are made to offer useful information for practical applications of the present method.

  11. Development of an unresolved CFD-DEM model for the flow of viscous suspensions and its application to solid-liquid mixing

    Blais, Bruno; Lassaigne, Manon; Goniva, Christoph; Fradette, Louis; Bertrand, François


    Although viscous solid-liquid mixing plays a key role in the industry, the vast majority of the literature on the mixing of suspensions is centered around the turbulent regime of operation. However, the laminar and transitional regimes face considerable challenges. In particular, it is important to know the minimum impeller speed (Njs) that guarantees the suspension of all particles. In addition, local information on the flow patterns is necessary to evaluate the quality of mixing and identify the presence of dead zones. Multiphase computational fluid dynamics (CFD) is a powerful tool that can be used to gain insight into local and macroscopic properties of mixing processes. Among the variety of numerical models available in the literature, which are reviewed in this work, unresolved CFD-DEM, which combines CFD for the fluid phase with the discrete element method (DEM) for the solid particles, is an interesting approach due to its accurate prediction of the granular dynamics and its capability to simulate large amounts of particles. In this work, the unresolved CFD-DEM method is extended to viscous solid-liquid flows. Different solid-liquid momentum coupling strategies, along with their stability criteria, are investigated and their accuracies are compared. Furthermore, it is shown that an additional sub-grid viscosity model is necessary to ensure the correct rheology of the suspensions. The proposed model is used to study solid-liquid mixing in a stirred tank equipped with a pitched blade turbine. It is validated qualitatively by comparing the particle distribution against experimental observations, and quantitatively by compairing the fraction of suspended solids with results obtained via the pressure gauge technique.


    Pafilis, Evangelos; Buttigieg, Pier Luigi; Ferrell, Barbra


    The microbial and molecular ecology research communities have made substantial progress on developing standards for annotating samples with environment metadata. However, sample manual annotation is a highly labor intensive process and requires familiarity with the terminologies used. We have the...... and text-mining-assisted curation revealed that EXTRACT speeds up annotation by 15-25% and helps curators to detect terms that would otherwise have been missed.Database URL:

  13. Using "Tender" X-ray Ambient Pressure X-Ray Photoelectron Spectroscopy as A Direct Probe of Solid-Liquid Interface.

    Axnanda, Stephanus; Crumlin, Ethan J; Mao, Baohua; Rani, Sana; Chang, Rui; Karlsson, Patrik G; Edwards, Mårten O M; Lundqvist, Måns; Moberg, Robert; Ross, Phil; Hussain, Zahid; Liu, Zhi


    We report a new method to probe the solid-liquid interface through the use of a thin liquid layer on a solid surface. An ambient pressure XPS (AP-XPS) endstation that is capable of detecting high kinetic energy photoelectrons (7 keV) at a pressure up to 110 Torr has been constructed and commissioned. Additionally, we have deployed a "dip &pull" method to create a stable nanometers-thick aqueous electrolyte on platinum working electrode surface. Combining the newly constructed AP-XPS system, "dip &pull" approach, with a "tender" X-ray synchrotron source (2 keV-7 keV), we are able to access the interface between liquid and solid dense phases with photoelectrons and directly probe important phenomena occurring at the narrow solid-liquid interface region in an electrochemical system. Using this approach, we have performed electrochemical oxidation of the Pt electrode at an oxygen evolution reaction (OER) potential. Under this potential, we observe the formation of both Pt(2+) and Pt(4+) interfacial species on the Pt working electrode in situ. We believe this thin-film approach and the use of "tender" AP-XPS highlighted in this study is an innovative new approach to probe this key solid-liquid interface region of electrochemistry.

  14. A Simple Approach to Characterize Gas-Aqueous Liquid Two-phase Flow Configuration Based on Discrete Solid-Liquid Contact Electrification.

    Choi, Dongwhi; Lee, Donghyeon; Kim, Dong Sung


    In this study, we first suggest a simple approach to characterize configuration of gas-aqueous liquid two-phase flow based on discrete solid-liquid contact electrification, which is a newly defined concept as a sequential process of solid-liquid contact and successive detachment of the contact liquid from the solid surface. This approach exhibits several advantages such as simple operation, precise measurement, and cost-effectiveness. By using electric potential that is spontaneously generated by discrete solid-liquid contact electrification, the configurations of the gas-aqueous liquid two-phase flow such as size of a gas slug and flow rate are precisely characterized. According to the experimental and numerical analyses on parameters that affect electric potential, gas slugs have been verified to behave similarly to point electric charges when the measuring point of the electric potential is far enough from the gas slug. In addition, the configuration of the gas-aqueous liquid two-phase microfluidic system with multiple gas slugs is also characterized by using the presented approach. For a proof-of-concept demonstration of using the proposed approach in a self-triggered sensor, a gas slug detector with a counter system is developed to show its practicality and applicability.

  15. Detailed monitoring of two biogas plants and mechanical solid-liquid separation of fermentation residues.

    Bauer, Alexander; Mayr, Herwig; Hopfner-Sixt, Katharina; Amon, Thomas


    The Austrian "green electricity act" (Okostromgesetz) has led to an increase in biogas power plant size and consequently to an increased use of biomass. A biogas power plant with a generating capacity of 500 kW(el) consumes up to 38,000 kg of biomass per day. 260 ha of cropland is required to produce this mass. The high water content of biomass necessitates a high transport volume for energy crops and fermentation residues. The transport and application of fermentation residues to farmland is the last step in this logistic chain. The use of fermentation residues as fertilizer closes the nutrient cycle and is a central element in the efficient use of biomass for power production. Treatment of fermentation residues by separation into liquid and solid phases may be a solution to the transport problem. This paper presents detailed results from the monitoring of two biogas plants and from the analysis of the separation of fermentation residues. Furthermore, two different separator technologies for the separation of fermentation residues of biogas plants were analyzed. The examined biogas plants correspond to the current technological state of the art and have designs developed specifically for the utilization of energy crops. The hydraulic retention time ranged between 45.0 and 83.7 days. The specific methane yields were 0.40-0.43 m(3)N CH(4) per kg VS. The volume loads ranged between 3.69 and 4.00 kg VS/m(3). The degree of degradation was between 77.3% and 82.14%. The screw extractor separator was better suited for biogas slurry separation than the rotary screen separator. The screw extractor separator exhibited a high throughput and good separation efficiency. The efficiency of slurry separation depended on the dry matter content of the fermentation residue. The higher the dry matter content, the higher the proportion of solid phase after separation. In this project, we found that the fermentation residues could be divided into 79.2% fluid phase with a dry matter

  16. Optimization onultrasonic-assisted extraction technology of flavonoids from pine nut shell with response surface analysis%松籽壳总黄酮超声提取工艺响应面优化

    董周永; 任辉; 周亚军


    Ultrasonic assisted extraction was applied to extract fla-vonoids from pine nut shell. By means of Box-Behnken design with four factors (ultrasonic power, ethanol concentration, solid-liquid ratio and extraction time) as influence factors, the optimal extraction technology was performed. The results indicated that the optimized ultrasonic-assisted extraction conditions of flavonoids from pine nut shell were obtained as follows: ultrasonic power 250 W, ethanol concentration 50% , solid-liquid ratio 1 : 25, extraction time 31 min. Under the above mentioned conditions, the yield of flavonoids from pine nut shell was 15. 37 mg/g.%为研究松籽壳总黄酮超声提取工艺,以超声波功率、乙醇体积分数、料液比、提取时间为考察因素,采用Box-Behnken试验设计进行工艺参数优化.结果表明,松籽壳总黄酮的最优提取工艺条件:超声波功率250 W、乙醇体积分数50%、料液比1:25(m∶V)、提取时间31 min.该条件下,松籽壳总黄酮得率为15.37 mg/g.

  17. Microwave-assisted extraction versus Soxhlet extraction for the analysis of short-chain chlorinated alkanes in sediments.

    Parera, J; Santos, F J; Galceran, M T


    Microwave-assisted extraction (MAE) was evaluated as a possible alternative to Soxhlet extraction for analysing short-chain chlorinated alkanes (commonly called short-chain chlorinated paraffins, SCCPs) in river sediment samples, using gas chromatography coupled to negative chemical ionisation mass spectrometry. For MAE optimisation, several extraction parameters such as solvent extraction mixture, extraction time and extraction temperature were studied. Maximum extraction efficiencies for SCCPs (90%) and for 12 polychlorinated biphenyl (PCB) congeners (91-95%) were achieved using 5 g of sediment sample, 30 ml of n-hexane-acetone (1:1, v/v) as solvent extraction, and 15 min and 115 degrees C of extraction time and temperature, respectively. Activated Florisil was used to clean-up the extracts, allowing highly selective separation of SCCPs from other organic contaminants such as PCBs. MAE was compared with a conventional extraction technique such as Soxhlet and good agreement in the results was obtained. Quality parameters of the optimised MAE method such as run-to-run (R.S.D. 7%) and day-to-day precision (R.S.D. 9%) were determined using spiked river sediment samples, with LODs of 1.5 ng g(-1). This method was successfully applied to the analysis of SCCPs in river sediment samples at concentrations below the ng g(-1) level. O 2004 Elsevier B.V. All rights reserved.

  18. Plant Phenolics: Extraction, Analysis and Their Antioxidant and Anticancer Properties

    Jin Dai


    Full Text Available Phenolics are broadly distributed in the plant kingdom and are the most abundant secondary metabolites of plants. Plant polyphenols have drawn increasing attention due to their potent antioxidant properties and their marked effects in the prevention of various oxidative stress associated diseases such as cancer. In the last few years, the identification and development of phenolic compounds or extracts from different plants has become a major area of health- and medical-related research. This review provides an updated and comprehensive overview on phenolic extraction, purification, analysis and quantification as well as their antioxidant properties. Furthermore, the anticancer effects of phenolics in-vitro and in-vivo animal models are viewed, including recent human intervention studies. Finally, possible mechanisms of action involving antioxidant and pro-oxidant activity as well as interference with cellular functions are discussed.

  19. Solid/liquid partition coefficients (Kd) for selected soils and sediments at Forsmark and Laxemar-Simpevarp

    Sheppard, Steve; Long, Jeff; Sanipelli, Barb (ECOMatters Inc., Pinawa (Canada)); Sohlenius, Gustav (Geological Survey of Sweden (SGU), Uppsala (Sweden))


    Soil and sediment solid/liquid partition coefficients (Kd) are used to indicate the relative mobility of radionuclides and elements of concern from nuclear fuel waste, as well as from other sources. The Kd data are inherently extremely variable, but also vary systematically with key environmental attributes. For soil Kd, the key variables are pH, clay content and organic carbon content. For sediment Kd, water type (freshwater versus marine) and sediment type (benthic versus suspended) are important. This report summarized Kd data for soils and sediments computed from indigenous stable element concentrations measured at the Forsmark and Laxemar-Simpevarp sites. These were then compared to several literature sources of Kd data for Ce, Cl, Co, Cr, Cs, Fe, Ho, I, La, Mn, Mo, Nb, Nd, Ni, Np, Pa, Pb, Pu, Ra, Sb, Se, Sm, Sn, Sr, Tc, Th, Tm, U and Yb. The Kd data computed from indigenous stable element concentrations may be especially relevant for assessment of long-lived radionuclides from deep disposal of waste, because the long time frame for the potential releases is more consistent with the steady state measured using indigenous stable elements. For almost every one of these elements in soils, a statistically meaningful regression equation was developed to allow estimation of Kd for any soil given a modest amount of information about the soil. Nonetheless, the median residual geometric standard deviation (GSD) was 4.3-fold, implying confidence bounds of about 18-fold above and below the best estimate Kd. For sediment, the values are categorised simply by water type and sediment type. The median GSD for sediment Kd as measured at the Forsmark and Laxemar-Simpevarp sites was 2.5-fold, but the median GSD among literature values was as high as 8.6-fold. Clearly, there remains considerable uncertainty in Kd values, and it is important to account for this in assessment applications

  20. Design and performance of BNR activated sludge systems with flat sheet membranes for solid-liquid separation.

    du Toit, G J G; Ramphao, M C; Parco, V; Wentzel, M C; Ekama, G A


    The use of immersed membranes for solid-liquid separation in biological nutrient removal activated sludge (BNRAS) systems was investigated at lab scale. Two laboratory-scale BNR activated sludge systems were run in parallel, one a MBR system and the other a conventional system with secondary settling tanks. Both systems were in 3 reactor anaerobic, anoxic, aerobic UCT configurations. The systems were set up to have, as far as possible, identical design parameters such as reactor mass fractions, recycles and sludge age. Differences were the influent flow and total reactor volumes, and the higher reactor concentrations in the MBR system. The performances of the two systems were extensively monitored and compared to identify and quantify the influence of the membranes on system response. The MBR UCT system exhibited COD, FSA, TKN, TP and TSS removals that were consistently equivalent or superior to the conventional system. Better P removal in the MBR was attributed to lower observed P uptake in the anoxic zone. High nitrate loads to the anoxic reactor appeared to be the determining factor in stimulating P uptake. The MBR UCT system had a greater sludge production than the conventional system. This was partly attributable to the retention of all solids in the MBR reactor. For steady state design this increase is accommodated by increasing the influent unbiodegradable particulate COD fraction. Additionally an attempt was made to determine the Alpha values in the oxygen transfer rate. This paper briefly summarises and compares the results from both systems, and the conclusions that can be drawn from these results.

  1. Optimized protein extraction methods for proteomic analysis of Rhizoctonia solani.

    Lakshman, Dilip K; Natarajan, Savithiry S; Lakshman, Sukla; Garrett, Wesley M; Dhar, Arun K


    Rhizoctonia solani (Teleomorph: Thanatephorus cucumeris, T. praticola) is a basidiomycetous fungus and a major cause of root diseases of economically important plants. Various isolates of this fungus are also beneficially associated with orchids, may serve as biocontrol agents or remain as saprophytes with roles in decaying and recycling of soil organic matter. R. solani displays several hyphal anastomosis groups (AG) with distinct host and pathogenic specializations. Even though there are reports on the physiological and histological basis of Rhizoctonia-host interactions, very little is known about the molecular biology and control of gene expression early during infection by this pathogen. Proteamic technologies are powerful tools for examining alterations in protein profiles. To aid studies on its biology and host pathogen interactions, a two-dimensional (2-D) gel-based global proteomic study has been initiated. To develop an optimized protein extraction protocol for R. solani, we compared two previously reported protein extraction protocols for 2-D gel analysis of R. solani (AG-4) isolate Rs23. Both TCA-acetone precipitation and phosphate solubilization before TCA-acetone precipitation worked well for R. solani protein extraction, although selective enrichment of some proteins was noted with either method. About 450 spots could be detected with the densitiometric tracing of Coomassie blue-stained 2-D PAGE gels covering pH 4-7 and 6.5-205 kDa. Selected protein spots were subjected to mass spectrometric analysis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Eleven protein spots were positively identified based on peptide mass fingerprinting match with fungal proteins in public databases with the Mascot search engine. These results testify to the suitability of the two optimized protein extraction protocols for 2-D proteomic studies of R. solani.

  2. Phytochemical analysis and antioxidant activities of Trigona Apicalis propolis extract

    Rosli, Nur Liyana; Roslan, Husniyati; Omar, Eshaifol Azam; Mokhtar, Norehan; Hapit, Nor Hussaini Abdul; Asem, Nornaimah


    Propolis is a resinous substance found in beehives. It provides beneficial effects on human health and has been used to treat many diseases since ancient times. The objectives of this study were to analyze the phytochemical profile of propolis derived from local T. apicalis species and its antioxidant activities. The ethanolic extract of propolis was subjected to HPLC analysis to analyze its phytochemical profile. The propolis extract was later tested for antioxidant capacities by using DPPH radical scavenging assay. TPC and TFC were performed to determine the correlation with its antioxidant activities. TEAC for each serial dilution sample was 2621.15 (4.76 mg/mL), 2050.85 (2.38 mg/mL), 1883.27 (1.19 mg/mL), 1562.67 (0.59 mg/mL), 1327.82 (0.29 mg/mL), 1164.49 (0.15 mg/mL), 983.27 (0.07 mg/mL), and 944.79 (0.04 mg/mL). The results demonstrated that the antioxidant activities of propolis extract were dose dependent. The IC50 of propolis for DPPH assay was 4.27 mg/ml. Correlation values of TPC and TFC against DPPH indicate that the antioxidant activities of propolis extract used in this study could be mainly influenced by the phenolic and flavonoid contents. These findings highlighted the importance of quality analysis in order to ensure the consistency of biological effects or therapy of a natural product, such as propolis.

  3. Extraction and Quantitative HPLC Analysis of Coumarin in Hydroalcoholic Extracts of Mikania glomerata Spreng: ("guaco" Leaves

    Celeghini Renata M. S.


    Full Text Available Methods for preparation of hydroalcoholic extracts of "guaco" (Mikania glomerata Spreng. leaves were compared: maceration, maceration under sonication, infusion and supercritical fluid extraction. Evaluation of these methods showed that maceration under sonication had the best results, when considering the ratio extraction yield/extraction time. A high performance liquid chromatography (HPLC procedure for the determination of coumarin in these hydroalcoholic extracts of "guaco" leaves is described. The HPLC method is shown to be sensitive and reproducible.

  4. Entropy Analysis as an Electroencephalogram Feature Extraction Method

    P. I. Sotnikov


    Full Text Available The aim of this study was to evaluate a possibility for using an entropy analysis as an electroencephalogram (EEG feature extraction method in brain-computer interfaces (BCI. The first section of the article describes the proposed algorithm based on the characteristic features calculation using the Shannon entropy analysis. The second section discusses issues of the classifier development for the EEG records. We use a support vector machine (SVM as a classifier. The third section describes the test data. Further, we estimate an efficiency of the considered feature extraction method to compare it with a number of other methods. These methods include: evaluation of signal variance; estimation of spectral power density (PSD; estimation of autoregression model parameters; signal analysis using the continuous wavelet transform; construction of common spatial pattern (CSP filter. As a measure of efficiency we use the probability value of correctly recognized types of imagery movements. At the last stage we evaluate the impact of EEG signal preprocessing methods on the final classification accuracy. Finally, it concludes that the entropy analysis has good prospects in BCI applications.

  5. 纤维素酶提取冬枣叶中总黄酮工艺的研究%Study on extraction technology of total flavones using cellulase from leaves of winter-jujube

    张圣燕; 张成


    Total flavones in leaves of winter-jujube were extracted using cellulose.The total flavones extraction rate was determined by spectrophotometry method with rutin as reference substance.In the single factor analysis,the effect of extraction temperature, extraction time, enzyme amount and solid - liquid ratio were measured. The orthogonal test was used to optimize the conditions of extraction.The results showed that the best conditions of extraction total flavones from leaves of winter - jujube were the solid - liquid ratio 1 : 50 ( g/mL), extraction temperature 55?, extraction time 90min, enzyme amount 4mg/g. Under this optimal condition, extraction rate was 2.45%.The results showed that the order of extraction rate of total flavones was as follows;extraction temperature > extraction time > enzyme amount > solid-liquid ratio.%采用纤维素酶提取冬枣叶中的总黄酮.以芦丁为标准品,采用分光光度法测定冬枣叶中总黄酮的含量,通过单因素实验研究提取温度、提取时间、酶用量和料液比对提取率的影响,再利用正交实验优化最佳提取工艺条件.结果表明,纤维素酶提取冬枣叶中总黄酮的最佳工艺条件为:料液比1:50(g/mL),提取温度55℃,提取时间90min,酶用量4mg/g.在最佳提取工艺条件下,提取率可达2.45%.同时得到各影响因素对总黄酮提取率的显著性影响顺序为:提取温度>提取时间>酶用量>料液比.

  6. Solid-liquid phase equilibrium of rapeseed protein and phenols%菜籽蛋白和酚的固-液相平衡

    刘晔; 沈娜娜; 刘大川


    With precipitation rate of rapeseed protein and partition coefficient of rapeseed protein-phe-nols as indexes, the solid-liquid phase equilibrium of coexistence system of rapeseed protein and phe-nols was studied so as to explore approaches for eliminating the phenols contamination in rapeseed pro-tein, and the improvement measures of extraction process of rapeseed protein was proposed based on the phase behavior characteristics. The results showed that in the alkaline environment, the coprecipitation of rapeseed protein with tannin or rapeseed polyphenols occurred and became more significant with concen-tration increasing;rapeseed protein showed the lowest solubility and its interactions with tannin or rape-seed polyphenols were the weakest at pH 4;the separation effect of rapeseed protein and phenols was fur-ther improved when 1% NaCl was added. Solvent dosage( ratio of liquid to solid) , pH and NaCl dosage had effects on the interactions between rapeseed protein and phenols in the extraction or enrichment process of rapeseed protein, and the optimization of these parameters was beneficial to enhance the selec-tivity of rapeseed protein extraction and reduce the contamination of phenols.%为探索消除菜籽蛋白中酚污染的技术途径,采用菜籽蛋白沉淀率和菜籽蛋白-酚分配系数为指标,考察了菜籽蛋白与酚共存体系的固-液相平衡关系,并基于相行为特征提出了菜籽蛋白提取工艺的改进措施。结果表明:在碱性环境下,酚酸和单宁均可与菜籽蛋白发生共沉淀作用,且浓度越高该作用越显著;在pH 4环境下,菜籽蛋白不仅溶解度最低,而且与单宁或菜籽多酚的结合作用最弱;而在溶液中添加1%的NaCl有利于进一步提升菜籽蛋白和酚的分离效果。在菜籽蛋白的富集或提取工艺中,溶剂用量(液固比)、pH以及盐添加量都可对菜籽蛋白和酚的相互作用产生影响,对这些参数的优化将有利于提

  7. A comparison of bacterial populations in enhanced biological phosphorus removal processes using membrane filtration or gravity sedimentation for solids-liquid separation.

    Hall, Eric R; Monti, Alessandro; Mohn, William W


    CEBPR system also revealed many uncultured organisms that have not been well characterized. The study demonstrated that a simple replacement of a secondary clarifier with membrane solids-liquid separation is sufficient to shift the composition of an activated sludge microbial community significantly. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  8. Independent component analysis for automatic note extraction from musical trills

    Brown, Judith C.; Smaragdis, Paris


    The method of principal component analysis, which is based on second-order statistics (or linear independence), has long been used for redundancy reduction of audio data. The more recent technique of independent component analysis, enforcing much stricter statistical criteria based on higher-order statistical independence, is introduced and shown to be far superior in separating independent musical sources. This theory has been applied to piano trills and a database of trill rates was assembled from experiments with a computer-driven piano, recordings of a professional pianist, and commercially available compact disks. The method of independent component analysis has thus been shown to be an outstanding, effective means of automatically extracting interesting musical information from a sea of redundant data.

  9. Comparative analysis of essential oil composition of Iranian and Indian Nigella sativa L. extracted using supercritical fluid extraction and solvent extraction.

    Ghahramanloo, Kourosh Hasanzadeh; Kamalidehghan, Behnam; Akbari Javar, Hamid; Teguh Widodo, Riyanto; Majidzadeh, Keivan; Noordin, Mohamed Ibrahim


    The objective of this study was to compare the oil extraction yield and essential oil composition of Indian and Iranian Nigella sativa L. extracted by using Supercritical Fluid Extraction (SFE) and solvent extraction methods. In this study, a gas chromatography equipped with a mass spectrophotometer detector was employed for qualitative analysis of the essential oil composition of Indian and Iranian N. sativa L. The results indicated that the main fatty acid composition identified in the essential oils extracted by using SFE and solvent extraction were linoleic acid (22.4%-61.85%) and oleic acid (1.64%-18.97%). Thymoquinone (0.72%-21.03%) was found to be the major volatile compound in the extracted N. sativa oil. It was observed that the oil extraction efficiency obtained from SFE was significantly (Pextraction technique. The present study showed that SFE can be used as a more efficient technique for extraction of N. Sativa L. essential oil, which is composed of higher linoleic acid and thymoquinone contents compared to the essential oil obtained by the solvent extraction technique.

  10. Stability analysis of underground openings for extraction of natural stone

    Karmen Fifer Bizjak


    Full Text Available Extraction of natural stone is usually carried out in surface quarries. Underground excavation is not a frequently used method. Due to the restrictive environmental legislature and limited stores of natural stone, underground extraction has become quite an interestingalternative. Dimensions of underground openings are determined with stability analyses.Prior to starting a numerical analysis of a large underground opening it is very important to determine the mechanism of failure and set up a proper numerical model. The continuum method is usually used in rock mechanics. A disadvantage of this calculation is that it cannotbe applied to a large number of joints. Other methods are preferred, such as the numerical discrete method, which allows joint systems to be involved into calculations. The most probable failure of rock with several joint systems is block sliding. In the example of themarble of Hotavlje both methods were used. It was established that the continuum method is convenient for the global stability prediction of the underground opening. Further discretemethod enable the block stability calculation. The analytical block analysis is still accurate for the a stability calculation of single block. The prerequisite for a good numerical analysis is sufficient quality data on geomechanical properties of rock. In-situ tests, laboratory tests and geotechnical measurements on the site are therefore necessary. Optimum dimensions of underground chambers in the Quarry of Hotavlje were calculated by using several numericalmodels, and the maximum chamber width of 12 m was obtained.

  11. Extraction, purification and antioxidant activity of polysaccharides from bamboo leaves

    GAO Ya-ni; TIAN Cheng-rui; ZHAO Li-li


    Ultrasonic extraction (UE) was employed for the extraction of bamboo leaf polysaccharides (BLP).The influential parameters of UE procedure including extraction time,ultrasonic power and solid/liquid ratio were optimized by orthogonal experiments.DEAE-cellulose column chromatography was applied to purify BLP and then the radical scavenging activity of BLP was also evaluated.Optimal extraction conditions were:extraction time of 15 min,ultrasonic power of 300 W,and solid/liquid ratio of 1:15.Four kinds of polysaccharides were obtained by DEAE-cellulose column chromatography; the maximum superoxide radical scavenging rate (20.4%) of BLP was inferior to that of vitamin C (Vc,the control) and the hydroxyl radical scavenging rate (50%) was equivalent to that of Vc.

  12. Preliminary design and analysis of a process for the extraction of lithium from seawater

    Steinberg, M.; Dang, V.D.


    The U.S. demand for lithium by the industrial sector and by a fusion power economy in the future is discussed. For a one million MW(e) CTR (D-T fuel cycle) economy, growing into the beginning of the next century (the years 2000 to 2030), the cumulative demand for lithium is estimated to range from (0.55 to 4.7) x 10/sup 7/ to 1.0 x 10/sup 9/ kg. Present estimates of the available U.S. supply are 6.9 x 10/sup 8/ kg of lithium from mineral resources and 4.0 x 10/sup 9/ kg of lithium from concentrated natural brines. There is, however, a vast supply of lithium in seawater: 2.5 x 10/sup 14/ kg. A preliminary process design for the extraction of lithium from seawater is presented: seawater is first evaporated by solar energy to increase the concentration of lithium and to decrease the concentration of other cations in the bittern which then passes into a Dowex-50 ion exchange bed for cation adsorption. Lithium ions are then eluted with dilute hydrochloric acid forming an aqueous lithium chloride which is subsequently concentrated and electrolyzed. The energy requirement for lithium extraction varies between 0.08 and 2.46 kWh(e)/gm for a range of production rates varying between 10/sup 4/ and 10/sup 8/ kg/y; this is small compared to the energy produced from the use of lithium in a CTR having a value of 3400 kWh(e)/g Li. Production cost of the process is estimated to be in the range of 2.2 to 3.2 cents/g Li. As a basis for the process design, it is recommended that a phase equilibria study of the solid--liquid crystallization processes of seawater be conducted. Uncertainties exist in the operation of large solar ponds for concentrating large quantities of seawater. A search for a highly selective adsorbent or extractant for Li from low concentration aqueous solutions should be made. Other physical separation processes such as using membranes should be investigated. 9 tables. (DLC)

  13. Studies on Extracting Ant Protein and Preparing the Nutritious Liquid of Amino Acid%蚂蚁蛋白提取及氨基酸营养液制备的研究

    于小磊; 郭雪松; 岳昊博


    To investigate the optimal synthesizing condition of the ant protein extraction by alkali process and single enzyme reaction. The alkali process extraction designed by L9(33) orthogonal method including measurement and analysis on lye concentration, soaking temperature (℃) and solid-liquid ratio. The ant protein extraction reached to 18.82%under the best dissolution condition of lye concentration 1.5%, soaking temperature 80℃, solid-liquid ratio 1:20. While In the single enzyme reaction, the kind of enzyme, temperature, time and solid-liquid ratio of the ant protein protease hydrolysis were tested and analyzed by L9(34) orthogonal method. Trypsin were obtained to be the comparatively suitable enzyme, and its hydrolysis rate reached to 19.28% under the optimal hydrolysis condition of pH 8.0, enzyme concentration 2.0%, temperature 40℃, solid-liquid ratio 1:7.5, total hydrolysis time 4 h. Conclusion: Single enzyme reaction improving the extraction rate of ant protein.%  为研究用碱法提取蚂蚁蛋白及用单酶水解的方法提取蚂蚁蛋白,考察其最佳工艺条件。采用L9(33)正交试验设计方法提取蚂蚁蛋白,分别对碱液浓度、浸泡温度、固液比进行实验与结果分析,以确定最佳溶解条件为:碱液浓度1.5%,浸泡温度80℃,固液比1:20,蚂蚁蛋白提取率达18.82%。然后采用L9(34)蚂蚁蛋白酶水解正交试验设计方法,对酶种类、温度、时间、固液比行实验与结果分析,确定胰蛋白酶为较适宜酶,最佳水解条件为:pH 8.0,酶量2.0%,反应温度40℃,固液比1:7.5,反应时间5 h,水解率达19.28%。用单酶水解的方法提取蚂蚁蛋白提取率高。

  14. Data Clustering Analysis Based on Wavelet Feature Extraction

    QIANYuntao; TANGYuanyan


    A novel wavelet-based data clustering method is presented in this paper, which includes wavelet feature extraction and cluster growing algorithm. Wavelet transform can provide rich and diversified information for representing the global and local inherent structures of dataset. therefore, it is a very powerful tool for clustering feature extraction. As an unsupervised classification, the target of clustering analysis is dependent on the specific clustering criteria. Several criteria that should be con-sidered for general-purpose clustering algorithm are pro-posed. And the cluster growing algorithm is also con-structed to connect clustering criteria with wavelet fea-tures. Compared with other popular clustering methods,our clustering approach provides multi-resolution cluster-ing results,needs few prior parameters, correctly deals with irregularly shaped clusters, and is insensitive to noises and outliers. As this wavelet-based clustering method isaimed at solving two-dimensional data clustering prob-lem, for high-dimensional datasets, self-organizing mapand U-matrlx method are applied to transform them intotwo-dimensional Euclidean space, so that high-dimensional data clustering analysis,Results on some sim-ulated data and standard test data are reported to illus-trate the power of our method.

  15. Extraction, chromatographic and mass spectrometric methods for lipid analysis.

    Pati, Sumitra; Nie, Ben; Arnold, Robert D; Cummings, Brian S


    Lipids make up a diverse subset of biomolecules that are responsible for mediating a variety of structural and functional properties as well as modulating cellular functions such as trafficking, regulation of membrane proteins and subcellular compartmentalization. In particular, phospholipids are the main constituents of biological membranes and play major roles in cellular processes like transmembrane signaling and structural dynamics. The chemical and structural variety of lipids makes analysis using a single experimental approach quite challenging. Research in the field relies on the use of multiple techniques to detect and quantify components of cellular lipidomes as well as determine structural features and cellular organization. Understanding these features can allow researchers to elucidate the biochemical mechanisms by which lipid-lipid and/or lipid-protein interactions take place within the conditions of study. Herein, we provide an overview of essential methods for the examination of lipids, including extraction methods, chromatographic techniques and approaches for mass spectrometric analysis.

  16. The Interaction Between an Insoluble Particle and an Advancing Solid/Liquid Interface: Micro-Gravity Experiments and Theoretical Developments

    Catalina, Adrian V.; Ssen, Subhayu; Stefanescu, Doru M.


    The interaction of an insoluble particle with an advancing solid/liquid interface (SLI) has been a subject of investigation for the past four decades. While the original interest stemmed from geology applications (e.g., frost heaving in soil), researchers soon realized that the complex science associated with such an interaction is relevant to many other scientific fields encompassing metal matrix composites (MMCs), high temperature superconductors, inclusion management in steel, growth of monotectics, and preservation of biological cells. During solidification of a liquid containing an insoluble particle, three distinct interaction phenomena have been experimentally observed: instantaneous engulfment of the particle, continuous pushing, and particle pushing followed by engulfment. It was also observed that for given experimental conditions and particle size there is a critical solidification velocity, V(sub cr), above which a particle is engulfed. During solidification of MMCs pushing leads to particle agglomeration at the grain boundaries and this has detrimental effects on mechanical properties of the casting. Consequently, the process must be designed for instantaneous engulfment to occur. This implies the development of accurate theoretical models to predict V(sub cr), and perform benchmark experiments to test the validity of such models. Although considerable progress has been made in understanding the pushing/engulfment phenomenon (PEP), its quantification in terms of the material and processing parameters remains a focus of research. Since natural convection currents occurring during terrestrial solidification experiments complicate the study of PEP, execution of experiments on the International Space Station (ISS) has been approved and funded by NASA. Extensive terrestrial (1g) experiments and preliminary micro-gravity (mu g) experiments on two space shuttle missions have been conducted in preparation for future experiments on the ISS. The investigated

  17. Solid-Liquid Dispersion in a Stirred Tank%固-液搅拌槽的分散性能

    张优; 尹喜祥; 黄雄斌


    在直径为0.478 m的立式搅拌槽中,采用高岭土和水为物料,比较了四斜叶、六直叶涡轮等8种桨的固-液分散性能及搅拌功率(P)、桨组合形式对分散性能的影响规律.结果表明,8种桨中分散效果最好的是六直叶涡轮桨和四斜叶桨,分散速率最快的是两叶CBY桨;分散速率与P1.08成正比;分散前期,搅拌功率增加,相对分散效果Y随之提高,当Y达到0.999以上,提高搅拌功率对搅拌效果几乎不起作用;采用分散速率较快(两叶CBY桨)与分散效果较好(四斜叶桨)的双桨组合,更适于连续操作过程.%The solid-liquid dispersion property by eight types of impeller such as four-pitched-blade turbine (PBT), Rushton turbine (RT), etc, and the influences of stirring power and impeller combinations on dispersion property were studied in a vertical stirred tank with diameter of 0.478 m. Kaolin particles were chosen as the particulate material to be dispersed in the water. The experimental results show that PBT and RT have the optimum dispersion performance, while the 2-blade CBY propeller has the shortest dispersion time. The dispersion rate is in the direct ratio of 1.08 to the stirring power. In the beginning period, the relative dispersion performance Y increases with the stirring power, but the stirring power has little influence on the dispersion performance when the relative dispersion performance Y is more than 0.999. The results also reveal that the combination of a bottom 2-blade CBY and an upper PBT has a clear advantage in continuous operation.

  18. Quantitative spatial analysis of the mouse brain lipidome by pressurized liquid extraction surface analysis

    Almeida, Reinaldo; Berzina, Zane; Christensen, Eva Arnspang


    of internal lipid standards in the extraction solvent. The analysis of lipid microextracts by nanoelectrospray ionization provides long-lasting ion spray which in conjunction with a hybrid ion trap-orbitrap mass spectrometer enables identification and quantification of molecular lipid species using a method......Here we describe a novel surface sampling technique termed pressurized liquid extraction surface analysis (PLESA), which in combination with a dedicated high-resolution shotgun lipidomics routine enables both quantification and in-depth structural characterization of molecular lipid species...... with successive polarity shifting, high-resolution Fourier transform mass spectrometry (FTMS), and fragmentation analysis. We benchmarked the performance of the PLESA approach for in-depth lipidome analysis by comparing it to conventional lipid extraction of excised tissue homogenates and by mapping the spatial...

  19. 酱油渣中油脂提取工艺的研究及其脂肪酸成分分析%Fat extraction from soy sauce residues and fatty acids composition analysis

    杨莹莹; 姚舜; 万海清; 余佳; 宋航


    Fat extraction from soy sauce residues and the analysis of composition and contents of fatty acids was studied. The extraction conditions were investigated and optimized by single factor and orthogonal experiments. The extracted fatty acids were analyzed by GC-MS. The results showed that the optimum extraction conditions were as follows: the ratio of petroleum ether to 80%vol ethanol 3:2, solid-liquid ratio 1 -1, extraction temperature 65℃, extraction time 2h and extraction 3 times. Under these conditions, the optimal entraction rate was 6.3%. Results of GC/MS indicated that there were 4 kinds of fatty acids in soy sauce oil, and among which the content of palmitic acid was 46.90% and the linoleic acid was 33.26%. This study was expected to provide support for further exploitation of the oil from soy sauce residues.%提取酱油渣中油脂,并对油脂中脂肪酸成分及含量进行了分析.通过单因素和正交试验,研究了油脂的最佳提取条件,采用气相-质谱(GC/MS)联用分析其脂肪酸组成及含量.试验表明:以石油醚和80%vol乙醇为溶剂,料液比1∶7,温度65℃,提取时间2h,3次提取,可以得到油脂的最佳提取率为6.3%.GC/MS分析表明,油脂中含有4种脂肪酸,其中软脂酸含量较高,为46.90%,亚油酸的含量次之,为33.26%.以上研究为酱油渣中油脂的进一步开发利用提供了依据.

  20. Quantity and unit extraction for scientific and technical intelligence analysis

    David, Peter; Hawes, Timothy


    Scientific and Technical (S and T) intelligence analysts consume huge amounts of data to understand how scientific progress and engineering efforts affect current and future military capabilities. One of the most important types of information S and T analysts exploit is the quantities discussed in their source material. Frequencies, ranges, size, weight, power, and numerous other properties and measurements describing the performance characteristics of systems and the engineering constraints that define them must be culled from source documents before quantified analysis can begin. Automating the process of finding and extracting the relevant quantities from a wide range of S and T documents is difficult because information about quantities and their units is often contained in unstructured text with ad hoc conventions used to convey their meaning. Currently, even simple tasks, such as searching for documents discussing RF frequencies in a band of interest, is a labor intensive and error prone process. This research addresses the challenges facing development of a document processing capability that extracts quantities and units from S and T data, and how Natural Language Processing algorithms can be used to overcome these challenges.

  1. Object-based Analysis for Extraction of Dominant Tree Species

    Meiyun; SHAO; Xia; JING; Lu; WANG


    As forest is of great significance for our whole development and the sustainable plan is so focus on it. It is very urgent for us to have the whole distribution,stock volume and other related information about that. So the forest inventory program is on our schedule. Aiming at dealing with the problem in extraction of dominant tree species,we tested the highly hot method-object-based analysis. Based on the ALOS image data,we combined multi-resolution in e Cognition software and fuzzy classification algorithm. Through analyzing the segmentation results,we basically extract the spruce,the pine,the birch and the oak of the study area. Both the spectral and spatial characteristics were derived from those objects,and with the help of GLCM,we got the differences of each species. We use confusion matrix to do the Classification accuracy assessment compared with the actual ground data and this method showed a comparatively good precision as 87% with the kappa coefficient 0. 837.

  2. Direct numerical simulation of gas-solid-liquid flows with capillary effects: An application to liquid bridge forces between spherical particles

    Sun, Xiaosong; Sakai, Mikio


    In this study, a numerical method is developed to perform the direct numerical simulation (DNS) of gas-solid-liquid flows involving capillary effects. The volume-of-fluid method employed to track the free surface and the immersed boundary method is adopted for the fluid-particle coupling in three-phase flows. This numerical method is able to fully resolve the hydrodynamic force and capillary force as well as the particle motions arising from complicated gas-solid-liquid interactions. We present its application to liquid bridges among spherical particles in this paper. By using the DNS method, we obtain the static bridge force as a function of the liquid volume, contact angle, and separation distance. The results from the DNS are compared with theoretical equations and other solutions to examine its validity and suitability for modeling capillary bridges. Particularly, the nontrivial liquid bridges formed in triangular and tetrahedral particle clusters are calculated and some preliminary results are reported. We also perform dynamic simulations of liquid bridge ruptures subject to axial stretching and particle motions driven by liquid bridge action, for which accurate predictions are obtained with respect to the critical rupture distance and the equilibrium particle position, respectively. As shown through the simulations, the strength of the present method is the ability to predict the liquid bridge problem under general conditions, from which models of liquid bridge actions may be constructed without limitations. Therefore, it is believed that this DNS method can be a useful tool to improve the understanding and modeling of liquid bridges formed in complex gas-solid-liquid flows.

  3. Direct numerical simulation of gas-solid-liquid flows with capillary effects: An application to liquid bridge forces between spherical particles.

    Sun, Xiaosong; Sakai, Mikio


    In this study, a numerical method is developed to perform the direct numerical simulation (DNS) of gas-solid-liquid flows involving capillary effects. The volume-of-fluid method employed to track the free surface and the immersed boundary method is adopted for the fluid-particle coupling in three-phase flows. This numerical method is able to fully resolve the hydrodynamic force and capillary force as well as the particle motions arising from complicated gas-solid-liquid interactions. We present its application to liquid bridges among spherical particles in this paper. By using the DNS method, we obtain the static bridge force as a function of the liquid volume, contact angle, and separation distance. The results from the DNS are compared with theoretical equations and other solutions to examine its validity and suitability for modeling capillary bridges. Particularly, the nontrivial liquid bridges formed in triangular and tetrahedral particle clusters are calculated and some preliminary results are reported. We also perform dynamic simulations of liquid bridge ruptures subject to axial stretching and particle motions driven by liquid bridge action, for which accurate predictions are obtained with respect to the critical rupture distance and the equilibrium particle position, respectively. As shown through the simulations, the strength of the present method is the ability to predict the liquid bridge problem under general conditions, from which models of liquid bridge actions may be constructed without limitations. Therefore, it is believed that this DNS method can be a useful tool to improve the understanding and modeling of liquid bridges formed in complex gas-solid-liquid flows.

  4. Determining the best extractant and extraction conditions for fulvic acid through qualitative and quantitative analysis of vermicompost

    Omid Shabnani Moghadam


    Full Text Available Fulvic acid is a natural tampon and an appropriate chelating agent that has high ion-exchange ability and increasing absorption of minerals in plants. This paper examined the effects of extractants (sodium hydroxide, sodium polyphosphate, urea and EDTA and the extraction time (1, 7 and 9 days on the physicochemical properties of vermicompost-produced fulvic acid. Finally, various methods were compared to the universal method of humic substances. Different qualitative and quantitative analysis such as detecting the functional groups (FTIR, measurement of functional groups, spectrophotometric ratios and humification indices were carried out on fulvic acid. Results showed that the highest and lowest amounts of fulvic acid were extracted by the sodium hydroxide and urea, respectively. Various extractants made negligible changes in the type and quality of the Fulvic acid functional groups. Results indicated that sodium hydroxide was the best extractant and the minimum amounts of fulvic acid were extracted by the urea. Urea-extracted fulvic acid had the most functional groups of total acidity and phenolic OH. The most carboxyl functional groups and spectrophotometric ratios were detected in EDTA solution. At the end, by the comparison of various methods, universal method despite the low extraction amount had more functional groups and higher efficiencies compare to others.

  5. Chromatographic analysis of water and wine samples for phenolic compounds released from food-contact epoxy resins.

    Lambert, C; Larroque, M


    Food-contact epoxy resins can release phenolic compounds such as phenol, m-cresol, bisphenol F, bisphenol A, 4-tert-butylphenol, bisphenol F diglycidyl ether (BFDGE), and bisphenol A diglycidyl ether (BADGE) into foodstuffs. A validated high-performance liquid chromatographic method with fluorometric detection is described for the simultaneous analysis of these compounds in wine and mineral water. Sample preparation by solid-liquid extraction enables detection limits of 2.5 micrograms/L in wine and 0.25 microgram/L in mineral water to be achieved. Recovery rates are close to 100%, except for BFDGE and BADGE (around 60% in wine and 75% in mineral water).

  6. Heat and Mass Transfer during Solid-Liquid Phase Transition of n-Alkanes in the C{sub 16} to C{sub 19} Range

    Holmen, Rune


    The main goal of this project has been to study heat and mass transfer during solid-liquid phase transition of n-alkanes in the in the C{sub 16} to C{sub 19} range. Phase transitions of both mixtures and pure components have been investigated. All experiments and simulations have been performed without any convection. Thermal conductivities have been determined at the melting point for solid and liquid unbranched alkanes ranging from C{sub 16} to C{sub 19}. An assessment of the error of the method has been performed. The measurements of solid conductivities are in accordance with measurements reported previously and confirm the applicability of the method. Liquid conductivities are higher than extrapolated values from the literature. The enhanced conductivity is believed to be caused by structural changes close to the melting point which is not taken into account when extrapolating values from the literature. Experiments have been performed for the purpose of investigating the freezing of mixtures of n-alkanes in the C{sub 16}-C{sub 19} range. The positions of the solid-liquid interfaces have been measured as freezing occurred. Calculations of the ratio of liquid and solid conductivities show that the solid structure of mixtures of the investigated n-alkanes is predominantly in a rotator structure at the temperatures investigated. There are indications of a transformation into an orthorhombic structure at lower temperatures. The temperatures on the solid-liquid interface have been measured, and compared with calculated values from chapter 4. The temperature of the interface is represented better by the measured interfacial temperatures than by the calculated interfacial temperatures. The experimental results indicate that the diffusion of heat is the limiting mechanism of phase transition. This result in a homogeneous liquid composition. A numerical model has been developed in order to simulate the experimental freezing of mixtures. The model represents the results

  7. Extracting Credible Dependencies for Averaged One-Dependence Estimator Analysis

    LiMin Wang


    Full Text Available Of the numerous proposals to improve the accuracy of naive Bayes (NB by weakening the conditional independence assumption, averaged one-dependence estimator (AODE demonstrates remarkable zero-one loss performance. However, indiscriminate superparent attributes will bring both considerable computational cost and negative effect on classification accuracy. In this paper, to extract the most credible dependencies we present a new type of seminaive Bayesian operation, which selects superparent attributes by building maximum weighted spanning tree and removes highly correlated children attributes by functional dependency and canonical cover analysis. Our extensive experimental comparison on UCI data sets shows that this operation efficiently identifies possible superparent attributes at training time and eliminates redundant children attributes at classification time.

  8. Extraction optimization, characterization and antioxidant activity of polysaccharide from Gentiana scabra bge.

    Cheng, Zhenyu; Zhang, Yuewei; Song, Haiyan; Zhou, Hongli; Zhong, Fangli; Hu, Haobin; Feng, Yu


    In this study, optimization of smashing tissue extraction (STE), preliminary chemical characterization and antioxidant activity in vitro of crude polysaccharides (CPS) from Gentiana scabra bge (G. scabra) were investigated. The optimal extraction conditions were determined as follows: sample particle size of 80mesh, solid/liquid ratio of 1:34, extraction voltage of 157.09V and extraction time of 130.38s. Under these conditions, the extraction yield of CPS had reached 15.03±0.14% (n=3). Chemical composition analysis indicated CPS was mainly composed of mannose, rhamnose, galacturonic acid, glcose, galactose, arabinose and fucose in a molar ratio of 1.00:9.89:51.59:35.37:38.06:99.13:21.34, respectively. The average molecular weight of CPS was estimated to be 3.8×10(4)Da. In addition, the potential antioxidant activity of CPS extracted by STE were demonstrated by DPPH radical scavenging assay, superoxide anion radical scavenging assay, hydroxyl radical scavenging assay and ferric reducing power assay. Overall, this study provided an effective extraction technique for G. scabra polysaccharides which would be explored as a promising natural antioxidant agent applied in functional foods or medicines.

  9. Blind extraction of an exoplanetary spectrum through Independent Component Analysis

    Waldmann, Ingo P; Deroo, Pieter; Hollis, Morgan D J; Yurchenko, Sergey N; Tennyson, Jonathan


    Blind-source separation techniques are used to extract the transmission spectrum of the hot-Jupiter HD189733b recorded by the Hubble/NICMOS instrument. Such a 'blind' analysis of the data is based on the concept of independent component analysis. The de-trending of Hubble/NICMOS data using the sole assumption that nongaussian systematic noise is statistically independent from the desired light-curve signals is presented. By not assuming any prior, nor auxiliary information but the data themselves, it is shown that spectroscopic errors only about 10 - 30% larger than parametric methods can be obtained for 11 spectral bins with bin sizes of ~0.09 microns. This represents a reasonable trade-off between a higher degree of objectivity for the non-parametric methods and smaller standard errors for the parametric de-trending. Results are discussed in the light of previous analyses published in the literature. The fact that three very different analysis techniques yield comparable spectra is a strong indication of th...


    Waldmann, I. P.; Tinetti, G.; Hollis, M. D. J.; Yurchenko, S. N.; Tennyson, J. [Department of Physics and Astronomy, University College London, Gower Street, WC1E 6BT (United Kingdom); Deroo, P., E-mail: [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099 (United States)


    Blind-source separation techniques are used to extract the transmission spectrum of the hot-Jupiter HD189733b recorded by the Hubble/NICMOS instrument. Such a 'blind' analysis of the data is based on the concept of independent component analysis. The detrending of Hubble/NICMOS data using the sole assumption that nongaussian systematic noise is statistically independent from the desired light-curve signals is presented. By not assuming any prior or auxiliary information but the data themselves, it is shown that spectroscopic errors only about 10%-30% larger than parametric methods can be obtained for 11 spectral bins with bin sizes of {approx}0.09 {mu}m. This represents a reasonable trade-off between a higher degree of objectivity for the non-parametric methods and smaller standard errors for the parametric de-trending. Results are discussed in light of previous analyses published in the literature. The fact that three very different analysis techniques yield comparable spectra is a strong indication of the stability of these results.

  11. Numerical simulation and analysis of solid-liquid two-phase three-dimensional unsteady flow in centrifugal slurry pump

    吴波; 汪西力; 徐海良


    Based on RNGk-ε turbulence model and sliding grid technique, solid−liquid two-phase three-dimensional (3-D) unsteady turbulence of full passage in slurry pump was simulated by means of Fluent software. The effects of unsteady flow characteristics on solid−liquid two-phase flow and pump performance were researched under design condition. The results show that clocking effect has a significant influence on the flow in pump, and the fluctuation of flow velocity and pressure is obvious, particularly near the volute tongue, at the position of small sections of volute and within diffuser. Clocking effect has a more influence on liquid-phase than on solid-phase, and the wake-jet structure of relative velocity of solid-phase is less obvious than liquid-phase near the volute tongue and the impeller passage outlet. The fluctuation of relative velocity of solid-phase flow is 7.6% smaller than liquid-phase flow at the impeller outlet on circular path. Head and radial forces of the impeller are 8.1% and 85.7% of fluctuation, respectively. The results provide a theoretical basis for further research for turbulence, improving efficient, reducing the hydraulic losses and wear. Finally, field tests were carried out to verify the operation and wear of slurry pump.

  12. Multiscale Phenomena in the Solid-Liquid Transition State of a Granular Material: Analysis, Modeling and Experimentation


    Methods in Geomechanics 33 pp 1737-1768. Tordesillas, A, Shi, J and Muhlhaus, H (2009) “Non-coaxiality and force chain evolution” International...Buckling force chains in dense granular assemblies: physical and numerical experiments” Geomechanics and Geoengineering 4(1) pp 3-16. Tordesillas, A...J, Tshaikiwsky, T (2010) “Stress-dilatancy and force chain evolution”, International Journal of Numerical and Analytical Methods in Geomechanics DOI

  13. Multiscale Phenomena in the Solid-Liquid Transition State of a Granular Material: Analysis and Modelling of Dense Granular Materials


    Geomechanics , (02 2011): 264. doi: 10.1002/nag.910 2011/08/24 01:39:39 10 David M. Walker, Antoinette Tordesillas, Colin Thornton, Robert P. Behringer, Jie...Computational Geomechanics . 2011/04/26 10:00:00, . : , 2011/08/30 08:52:12 17 TOTAL: 3 (d) Manuscripts Number of Peer-Reviewed Conference Proceeding...Bifurcations and Degradations in Geomechanics . (In press) The techniques in [1]-[2] are extended to a broader range of experimental and simulation

  14. A Simplified Rice DNA Extraction Protocol for PCR Analysis

    CHEN Wen-yue; CUI Hai-rui; BAO Jin-song; ZHOU Xiang-sheng; SHU Qing-yao


    A simple protocol was established for DNA extraction using etiolated rice seedlings, whereby rice DNA was directly extracted ir 0.5 mol/L NaOH solution in a single eppendorf tube. Results of comparative PCR analyses and electrophoresis showed that the DNA extracted using this method was as good and useful as that using standard CTAB method.

  15. Extraction and identification of flavonoids from parsley extracts by HPLC analysis

    Stan, M.; Soran, M. L.; Varodi, C.; Lung, I.


    Flavonoids are phenolic compounds isolated from a wide variety of plants, and are valuable for their multiple properties, including antioxidant and antimicrobial activities. In the present work, parsley (Petroselinum crispum L.) extracts were obtained by three different extraction techniques: maceration, ultrasonic-assisted and microwave-assisted solvent extractions. The extractions were performed with ethanol-water mixtures in various ratios. From these extracts, flavonoids like the flavones apigenin and luteolin, and the flavonols quercetin and kaempferol were identified using an HPLC Shimadzu apparatus equipped with PDA and MS detectors. The separation method involved a gradient step. The mobile phase consisted of two solvents: acetonitrile and distilled water with 0.1% formic acid. The separation was performed on a RP-C18 column.


    P. Somasundaran


    The aim of the project is to develop a knowledge base to help the design of enhanced processes for mobilizing and extracting untrapped oil. We emphasize evaluation of novel surfactant mixtures and obtaining optimum combinations of the surfactants for efficient chemical flooding EOR processes. In this regard, an understanding of the aggregate shape, size and structure is crucial since these properties govern the crude oil removal efficiency. During the three-year period, the adsorption and aggregation behavior of sugar-based surfactants and their mixtures with other types of surfactants have been studied. Sugar-based surfactants are made from renewable resources, nontoxic and biodegradable. They are miscible with water and oil. These environmentally benign surfactants feature high surface activity, good salinity, calcium and temperature tolerance, and unique adsorption behavior. They possess the characteristics required for oil flooding surfactants and have the potential for replacing currently used surfactants in oil recovery. A novel analytical ultracentrifugation technique has been successfully employed for the first time, to characterize the aggregate species present in mixed micellar solution due to its powerful ability to separate particles based on their size and shape and monitor them simultaneously. Analytical ultracentrifugation offers an unprecedented opportunity to obtain important information on mixed micelles, structure-performance relationship for different surfactant aggregates in solution and their role in interfacial processes. Initial sedimentation velocity investigations were conducted using nonyl phenol ethoxylated decyl ether (NP-10) to choose the best analytical protocol, calculate the partial specific volume and obtain information on sedimentation coefficient, aggregation mass of micelles. Four softwares: OptimaTM XL-A/XL-I data analysis software, DCDT+, Svedberg and SEDFIT, were compared for the analysis of sedimentation velocity

  17. Instrument for Solvent Extraction and Analysis (ISEE) of Organics from Regolith Simulant Using Supercritical Fluid Extraction and Chromatography

    Franco, Carolina; Hintze, Paul E.


    ISEE is an instrument with the potential to perform extractions from regolith found on the surface of asteroids and planets, followed by characterization and quantitation of the extracts using supercritical fluid extraction (SFE) and chromatography (SFC). SFE is a developed technique proven to extract a wide range of organic compounds. SFC is similar to High Performance Liquid Chromatography (HPLC) but has the advantage of performing chiral separations without needing to derivatize the chiral compounds. CO2 will be the solvent for both stages as it is readily available in the Mars atmosphere. ISEE will capture CO2 from the environment, and use it for SFE and SFC. If successful, this would allow ISEE to perform analysis of organic compounds without using consumables. This paper will present results on a preliminary, proof-of-principle effort to use SFE and SFC to extract and analyze lunar regolith simulant spiked with organic compounds representing a range of organics that ISEE would expect to characterize. An optimization of variables for the extraction of the organics from the spiked regolith was successfully developed, using 138 bar pressure and 40 C temperature. The extraction flow rate was optimized at 2% SLPM with 30% methanol modifier. The extractions were successful with a value of 77.3+/- 0.9% of organics extracted. However, the recovery of organics after the extraction was very low with only 48.5+/-14.2%. Moreover, three columns were selected to analyze multiple samples at a time; two of them are Viridis HSS C18 SB and Torus DIOL, and the third column, specific for chiral separations, has not yet been selected yet.

  18. Extraction and analysis of polycyclic aromatic hydrocarbons (PAHs) by solid phase micro-extraction/supercritical fluid chromatography (SPME/SFC)

    Lesellier, E. [Institut Universitaire de Technologie, (LETIAM), 91 - Orsay (France)


    Solid phase micro-extraction (SPME) is a clean and simple pre-concentration method. Previously used for trace analysis of volatile compounds, the use of SPME was extended to non volatile molecules with the development of an SPME/HPLC interface. This new interface allows the extraction and the analysis of high molecular weight compounds found in aqueous samples. Since superficial fluid chromatography is particularly well suited for analysis of complex mixtures containing non volatile compounds, the feasibility of coupling SPME and SFC has been investigated and applied to PAHs. Several points have been studied: behavior of interface and of fiber to superficial fluid and high pressure required by the analytical method; kind of the compounds transfer from the fiber to the analytical column; relation between the nature of the fibers and the quantity of extracted compounds; effect of salt addition. The results show that the SPME/SFC technic may be used for extraction and analysis of PAHs, since the quantity of extracted compounds reach 30 %. (author) 17 refs.

  19. Microwave-Assisted Extraction Followed by Solid-Phase Extraction for the Chromatographic Analysis of Alkaloids in Stephania cepharantha.

    Liu, Ying; Xie, Daotao; Kang, Yun; Wang, Yaqin; Yang, Ping; Guo, Jixian; Huang, Jianming


    A procedure involving microwave-assisted extraction (MAE) followed by solid-phase extraction (SPE) was established for the extraction and purification of three bisbenzylisoquinoline alkaloids from Stephania cepharantha, and a reversed-phase high-performance liquid chromatography (HPLC) method was developed for the quantification of the target alkaloids. Chromatographic separation was achieved on a Phenomenex Luna Phenyl-Hexyl column. Prior to the HPLC analysis, the alkaloids were rapidly extracted by an optimized MAE process using 0.01 mol/L hydrochloric acid as the solvent. The MAE extract was subsequently purified by SPE using a cation-exchange polymeric cartridge. The MAE-SPE procedure extracted the three alkaloids with satisfactory recoveries ranging from 100.44 to 102.12%. In comparison with the MAE, Soxhlet and ultrasonic-assisted extractions, the proposed MAE-SPE method showed satisfactory cleanup efficiency. Thus, the validated MAE-SPE-HPLC method is specific, accurate and applicable to the determination of alkaloids in S. cepharantha.

  20. Vine-shoot waste aqueous extracts for re-use in agriculture obtained by different extraction techniques: phenolic, volatile, and mineral compounds.

    Sánchez-Gómez, Rosario; Zalacain, Amaya; Alonso, Gonzalo L; Salinas, M Rosario


    Vine-shoots are an important waste in all viticulture areas that should be re-used with innovative applications. The aim of this work was to produce Airén waste vine-shoot aqueous extracts by four solid-liquid extraction techniques such as conventional solid-liquid extraction (CSLE), solid-liquid dynamic extraction (SLDE-Naviglio), microwave extraction (ME), and pressurized solvent extraction (PSE). Their chemical composition was studied in terms of phenolic, volatile, and mineral compounds. The highest concentrated extracts corresponded to CSLE and SLDE-Naviglio, independent of the conditions tested. The CSLE extracts had the highest flavanols, phenolic acids, and stilbenes contents. The volatile composition, quantified for first time in this work, shows that furanic compounds were the most abundant. All extracts showed an interesting mineral content, which may be assimilated by plants. These results show the agricultural potential of Airén vine-shoot waste aqueous extracts to be used as grape biostimulants and/or foliar fertilizer.

  1. Phosphogypsum analysis: total content and extractable element concentrations

    Gennari, Roseli F.; Medina, Nilberto H., E-mail:, E-mail: [Departamento de Fisica Nuclear, Instituto de Fisica (USP), Sao Paulo, SP (Brazil); Garcia, Isabella; Silveira, Marcilei A.G., E-mail: [Centro Universitario da FEI. Sao Bernardo do Campo, SP (Brazil)


    Phosphogypsum stand for the chemical origin gypsum generated in fertilizers production, in which phosphate rock is attacked by sulfuric acid resulting in phosphoric acid (H{sub 3}PO{sub 4}) and phosphate fertilizers. Phosphogypsum is not a commercial product and it is stocked in large open areas or accumulated in lakes inducing to a major environmental problem due to the presence of toxic and radioactive elements. The increasing world agricultural demand is the real responsible for the severity of this environmental problem. Nevertheless, there are some possibilities for the application of this reject material, such as civil construction, waste water treatment, and in cultivated lands, etc. In the agriculture the phosphogypsum is commonly used as a nutrient source due to its large amounts of phosphorus, calcium and sulfur. However, there are still some environmental questions related to the use of this by-product since phosphogypsum is classified as TENORM (Technologically Enhanced Naturally Occurring Radioactive Material), which is a solid waste containing heavy metals and naturally occurring radioactive elements from the rock matrix. In this work, Plasma Mass Spectrometry (ICP-MS) was used to study phosphogypsum samples. Several acid solutions for samples digestion were evaluated in order to be feasible the chemical analysis. BCR sequential extractions were also performed. The results showed analyte concentrations are highly dependent on the acid solution used. The BCR guidelines could not be applied as used for soil, since the phosphogypsum solubility is different. So, it would be necessary to use different mass aliquots in the extractions, to be feasible an environmental evaluation. (author)

  2. 新型固-液旋流分离过程的建模与仿真研究%Modeling and Simulation Research About the Separation Process of a New Solid-liquid Hydrocyclone Separator

    宛西原; 漆磊; 汪霞


    For some problems of the new solid - liquid hydrocyclone in actual operation , designing a new diversion cyclone separator which is of high separation efficiency. By analyzing the principle of the cyclone separator , fluid mechanics fundamental laws combined with cylindrical cyclone separator modeling , establishing mathematical modeling of solid-liquid diversion cyclone separator. Found the speed of the new cyclone separator feed inlet velocity by calculation and simulation, in order to further study the flow field structure of the cyclone separator, applying the FLUENT software combined with Eulerian multiphase analysis and RNG k-ε turbulence modeling to simulate cyclone separator’s flow field. Obtain the visualization result of the flow field pressure distribution , velocity distribution and the particle trajectories distribution. the result shows that the special structure of the deflector designed in the cyclone separator can effectively refine the degradation of circulation flow and improve the separation efficiency of the cyclone separator , provide the technical guidance and theoretical foundation for the cyclone separator can separate diameter of particles is around 5 um and more than that.%针对新型固-液旋流分离器实际工作环境,设计了一种新型导流式高效旋流分离器,利用流体力学基本原理,结合T.D哈帝冈柱形旋流分离器模型,建立了新型导流式固液旋流分离器的数学及仿真模型,通过仿真实验获取了新型旋流分离器流场稳定时的进料口速度。运用FLUENT软件,结合欧拉多相流分析法和RNGk-ε湍流模型对其进行数值模拟,得到了流场的压力分布、速度分布、粒子轨迹分布等可视化结果。结果表明,在新型旋流分离器中设计的导流板这一特殊结构能够有效改善循环流,并提高该旋流分离器的分离效率,为旋流分离器取得较好分离效果的工作参数设定提供了技术指导和理论依据。

  3. Microanalytical techniques applied to phase identification and measurement of solute redistribution at the solid/liquid interface of frozen Fe-4.3Ni doublets

    Faryna, M; Okane, T


    A Fe-4.3M alloy has been solidified directionally by using the Bridgman system. The solidification conditions were chosen to obtain an oriented cellular structure of delta-ferrite. These are: a positive temperature gradient of about 60 K/cm and a growth rate of 6.6 mu m/s. A change in these conditions can lead either to the formation of austenite or to the competitive growth of delta-ferrite/gamma-austenite. The solid/liquid interface of delta-ferrite cells has been frozen and double instability has been revealed at the tip of the cells. The instability is described as the first harmonic wave of fundamental undulation, which appeared at the formerly planar solid/liquid interface. This means that a doublet structure is formed only with the imposed specific conditions of solidification. The Ni-solute redistribution after back-diffusion has been measured across the delta-ferrite doublet. Results of energy dispersive x-ray (EDX) measurements on the distribution of Ni and Fe correspond well to the theoretical pred...

  4. Evolution of solid-liquid interface morphology of primary TiB2 in non-equilibrium solidified Ti-Al-B alloys

    张虎; 高文理; 金云学; 曾松岩


    Ti-Al-B alloys were produced by in-situ synthesis method. The phase constitutions, microstructure of these alloys and the morphology of the primary TiB2 were investigated by XRD and SEM. The results show that these alloys are composed of TiAl and TiB2, and the primary TiB2 is hexagonal prism shape. Growth terraces, pyramidal protrusion, and rod shape dendrites are observed on (0001) plane of primary TiB2. There are thin flake convexes on plane of primary TiB2, parallel to (0001) plane of the primary TiB2. The rod-shaped crystal orientation and thin flake convexes are parallel to primary TiB2 where they protrude out. The solid-liquid interface morphology of primary TiB2 during solidification was also investigated. It was indicated that the solid-liquid interface morphology of primary TiB2 is instable and gradually develops into a complicated interface consisted of a few separated secondary interfaces. These secondary interfaces are facet with the same crystalline orientation.

  5. Novel, low-cost solid-liquid-solid process for the synthesis of α-Si3N4 nanowires at lower temperatures and their luminescence properties.

    Liu, Haitao; Huang, Zhaohui; Huang, Juntong; Fang, Minghao; Liu, Yan-gai; Wu, Xiaowen; Hu, Xiaozhi; Zhang, Shaowei


    Ultra-long, single crystal, α-Si3N4 nanowires sheathed with amorphous silicon oxide were synthesised by an improved, simplified solid-liquid-solid (SLS) method at 1150 °C without using flowing gases (N2, CH4, Ar, NH3, etc.). Phases, chemical composition, and structural characterisation using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM/HRTEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) showed that the nanowires had Si3N4@SiOx core-shell structures. The growth of the nanowires was governed by the solid-liquid-solid (SLS) mechanism. The room temperature photoluminescence (PL) and cathodoluminescence (CL) spectra showed that the optical properties of the α-Si3N4 nanowires can be changed along with the excitation wavelength or the excitation light source. This work can be useful, not only for simplifying the design and synthesis of Si-related nanostructures, but also for developing new generation nanodevices with changeable photoelectronic properties.

  6. Hydrolysis-acidogenesis of food waste in solid-liquid-separating continuous stirred tank reactor (SLS-CSTR) for volatile organic acid production.

    Karthikeyan, Obulisamy Parthiba; Selvam, Ammaiyappan; Wong, Jonathan W C


    The use of conventional continuous stirred tank reactor (CSTR) can affect the methane (CH4) recovery in a two-stage anaerobic digestion of food waste (FW) due to carbon short circuiting in the hydrolysis-acidogenesis (Hy-Aci) stage. In this research, we have designed and tested a solid-liquid-separating CSTR (SLS-CSTR) for effective Hy-Aci of FW. The working conditions were pH 6 and 9 (SLS-CSTR-1 and -2, respectively); temperature-37°C; agitation-300rpm; and organic loading rate (OLR)-2gVSL(-1)day(-1). The volatile fatty acids (VFA), enzyme activities and bacterial population (by qPCR) were determined as test parameters. Results showed that the Hy-Aci of FW at pH 9 produced ∼35% excess VFA as compared to that at pH 6, with acetic and butyric acids as major precursors, which correlated with the high enzyme activities and low lactic acid bacteria. The design provided efficient solid-liquid separation there by improved the organic acid yields from FW.

  7. Adsorption of Eu(III on oMWCNTs: Effects of pH, Ionic Strength, Solid-Liquid Ratio and Water-Soluble Fullerene

    P. Liu


    Full Text Available The influences of pH, ionic strength, solid-liquid ratio, , and on Eu(III adsorption onto the oxidation multiwalled carbon nanotubes (oMWCNTs were studied by using batch technique. The dynamic process showed that the adsorption of Eu(III onto oMWCNTs could be in equilibrium for about 17 h and matched the quasi-second-order kinetics model. The sorption process was influenced strongly by pH changes and ionic strength. In the pH range of 1.0 to 4.0, the adsorption ratio increased with the increasing of pH values, then the adsorption of Eu(III was almost saturated in the pH range of 4.0 to 10.0, and the adsorption ratio reached about 90%. The adsorption ratio decreased with the increasing of ionic strength. could promote the adsorption process obviously, but competed with Eu(III for the adsorption sites, thus leading to the reducing of Eu(III adsorption onto oMWCNTs. In the presence of or , the adsorption of Eu(III onto oMWCNTs could be affected obviously by solid-liquid ratio and the initial concentration of Eu(III.

  8. Dramatically different kinetics and mechanism at solid/liquid and solid/gas interfaces for catalytic isopropanol oxidation over size-controlled platinum nanoparticles.

    Wang, Hailiang; Sapi, Andras; Thompson, Christopher M; Liu, Fudong; Zherebetskyy, Danylo; Krier, James M; Carl, Lindsay M; Cai, Xiaojun; Wang, Lin-Wang; Somorjai, Gabor A


    We synthesize platinum nanoparticles with controlled average sizes of 2, 4, 6, and 8 nm and use them as model catalysts to study isopropanol oxidation to acetone in both the liquid and gas phases at 60 °C. The reaction at the solid/liquid interface is 2 orders of magnitude slower than that at the solid/gas interface, while catalytic activity increases with the size of platinum nanoparticles for both the liquid-phase and gas-phase reactions. The activation energy of the gas-phase reaction decreases with the platinum nanoparticle size and is in general much higher than that of the liquid-phase reaction which is largely insensitive to the size of catalyst nanoparticles. Water substantially promotes isopropanol oxidation in the liquid phase. However, it inhibits the reaction in the gas phase. The kinetic results suggest different mechanisms between the liquid-phase and gas-phase reactions, correlating well with different orientations of IPA species at the solid/liquid interface vs the solid/gas interface as probed by sum frequency generation vibrational spectroscopy under reaction conditions and simulated by computational calculations.

  9. Comparison of different strategies for soybean antioxidant extraction.

    Chung, Hyun; Ji, Xiangming; Canning, Corene; Sun, Shi; Zhou, Kequan


    Three extraction strategies including Soxhlet extraction, conventional solid-liquid extraction, and ultrasonic-assisted extraction (UAE) were compared for their efficiency to extract phenolic antioxidants from Virginia-grown soybean seeds. Five extraction solvents were evaluated in UAE and the conventional extraction. The soybean extracts were compared for their total phenolic contents (TPC), oxygen radical absorbance capacity (ORAC), and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) scavenging activities. The results showed that UAE improved the extraction of soybean phenolic compounds by >54% compared to the conventional and Soxhlet extractions. Among the tested solvents, 50% acetone was the most efficient for extracting soybean phenolic compounds. There was no significant correlation between the TPC and antioxidant activities of the soybean extracts. The extracts prepared by 70% ethanol had the highest ORAC values. Overall, UAE with 50% acetone or 70% ethanol is recommended for extracting soybean antioxidants on the basis of the TPC and ORAC results.

  10. Information- Theoretic Analysis for the Difficulty of Extracting Hidden Information

    ZHANG Wei-ming; LI Shi-qu; CAO Jia; LIU Jiu-fen


    The difficulty of extracting hidden information,which is essentially a kind of secrecy, is analyzed by information-theoretic method. The relations between key rate, message rate, hiding capacity and difficulty of extraction are studied in the terms of unicity distance of stego-key, and the theoretic conclusion is used to analyze the actual extracting attack on Least Significant Bit(LSB) steganographic algorithms.

  11. Simultaneous extraction, optimization, and analysis of flavonoids and polyphenols from peach and pumpkin extracts using a TLC-densitometric method.

    Altemimi, Ammar; Watson, Dennis G; Kinsel, Mary; Lightfoot, David A


    The use of medicinal plants has been reported throughout human history. In the fight against illnesses, medicinal plants represent the primary health care system for 60 % of the world's population. Flavonoids are polyphenolic compounds with active anti-microbial properties; they are produced in plants as pigments. Quercetin, myricetin, and rutin are among the most well-known and prevalent flavonoids in plants, with an antioxidant activity capable of decreasing the oxidation of low density lipoproteins [LDLs]. To date, this research is the first of its kind to employ a coupled thin-layer chromatography (TLC) and a densitometric quantification method with a Box-Behnken design (BBD) response surface methodology (RSM) for optimization of ultrasonic-assisted extraction and determination of rutin and quercetin from peach and ellagic acid and myricetin from pumpkin fruits. The effect of process variables (extraction temperature (°C), extraction power (%) and extraction time (min)) on ultrasound-assisted extraction (UAE) were examined by using BBD and RSM. TLC followed by Quantity-One™ (BioRad) image analysis as a simple and rapid method was used for identification and quantification of the compounds in complex mixtures. The results were consistent under optimal conditions among the experimental values and their predicted values. A mass spectrometry (MALDI-TOF MS) technique was also used to confirm the identity of the natural products in the TLC spots resolved. The results show that the coupled TLC-densitometric methods & BBD can be a very powerful approach to qualitative and quantitative analysis of; rutin and quercetin from peach extracts; and ellagic acid and myricetin contents from pumpkin extracts.

  12. Comparative analysis of protocols for DNA extraction from soybean caterpillars.

    Palma, J; Valmorbida, I; da Costa, I F D; Guedes, J V C


    Genomic DNA extraction is crucial for molecular research, including diagnostic and genome characterization of different organisms. The aim of this study was to comparatively analyze protocols of DNA extraction based on cell lysis by sarcosyl, cetyltrimethylammonium bromide, and sodium dodecyl sulfate, and to determine the most efficient method applicable to soybean caterpillars. DNA was extracted from specimens of Chrysodeixis includens and Spodoptera eridania using the aforementioned three methods. DNA quantification was performed using spectrophotometry and high molecular weight DNA ladders. The purity of the extracted DNA was determined by calculating the A260/A280 ratio. Cost and time for each DNA extraction method were estimated and analyzed statistically. The amount of DNA extracted by these three methods was sufficient for PCR amplification. The sarcosyl method yielded DNA of higher purity, because it generated a clearer pellet without viscosity, and yielded high quality amplification products of the COI gene I. The sarcosyl method showed lower cost per extraction and did not differ from the other methods with respect to preparation times. Cell lysis by sarcosyl represents the best method for DNA extraction in terms of yield, quality, and cost effectiveness.

  13. Optimization of Multistage Extraction of Olive Leaves for Recovery of Phenolic Compounds at Moderated Temperatures and Short Extraction Times

    Konstantinos Stamatopoulos


    Full Text Available The aim of the present study was to improve the recovery of polyphenols from olive leaves (OL by optimizing a multistage extraction scheme; provided that the olive leaves have been previously steam blanched. The maximum total phenol content expressed in ppm caffeic acid equivalents was obtained at pH 2, particle size 0.315 mm, solid-liquid ratio 1:7 and aqueous ethanol concentration 70% (v/v. The optimum duration time of each extraction stage and the operation temperature, were chosen based on qualitative and quantitative analysis of oleuropein (OLE, verbascoside, luteolin-7-O-glucoside and apigenin-7-O-glucoside performed by high performance liquid chromatography with diode array detector (HPLC-DAD. The optimum conditions for multistage extraction were 30 min total extraction time (10 min × 3 stages at 85 °C. The 80% of the total yield of polyphenols was obtained at the 1st stage of the extraction. The total extraction yield of oleuropein was found 23 times higher (103.1 mg OLE/g dry weight (d.w. OL compared to the yield (4.6 mg OLE/g d.w. OL obtained by the conventional extraction method (40 °C, 48 h. However, from an energetic and hence from an economical point of view it is preferable to work at 40 °C, since the total extraction yield of polyphenolic compounds was only 17% higher for a double increase in the operating temperature (i.e., 85 °C.

  14. An Automated Video Object Extraction System Based on Spatiotemporal Independent Component Analysis and Multiscale Segmentation

    Zhang Xiao-Ping


    Full Text Available Video content analysis is essential for efficient and intelligent utilizations of vast multimedia databases over the Internet. In video sequences, object-based extraction techniques are important for content-based video processing in many applications. In this paper, a novel technique is developed to extract objects from video sequences based on spatiotemporal independent component analysis (stICA and multiscale analysis. The stICA is used to extract the preliminary source images containing moving objects in video sequences. The source image data obtained after stICA analysis are further processed using wavelet-based multiscale image segmentation and region detection techniques to improve the accuracy of the extracted object. An automated video object extraction system is developed based on these new techniques. Preliminary results demonstrate great potential for the new stICA and multiscale-segmentation-based object extraction system in content-based video processing applications.

  15. The Extraction Process of Octacosanol from Beeswax%蜂蜡中二十八烷醇的制备工艺研究

    杨浩; 李利龙; 吴信; 向洋


    Octacosanol was prepared by beeswax. Temperature and time for saponification, NaOH concentration , the effect of the solid-liquid ratio on the extraction of saponification were studied. The result of orthogonal test and variance analysis showed that the optimal saponification conditions were: 95 ℃, 3.5 h, 8 % of the mixture of NaOH and CH3CH2OH, 1:8 of solid - liquid ratio. By purification and molecular distillation technology 89.78% of alcohol had obtained.%以蜂蜡为原料制备二十八烷醇,研究了皂化温度、皂化时间、NaOH体积分数、固液比等单因素对皂化提取过程的影响,通过正交试验及其方差分析结果确定最优皂化条件为:皂化温度95 ℃C、皂化时间3.5h、NaOH体积分数为8%、固液比为1∶8.然后经过分子蒸馏技术纯化可以制得最高纯度为89.78%的二十八烷醇.

  16. [DNA extraction methods of compost for molecular ecology analysis].

    Yang, Zhao-Hui; Xiao, Yong; Zeng, Guang-Ming; Liu, Yun-Guo; Deng, Jiu-Hua


    Molecular ecology provides new techniques for studying compost microbes, and the DNA extraction is the basis of molecular techniques. Because of the contamination of humic acids, it turns to be more difficult for compost microbial DNA extraction. Three different approaches, named as lysozyme lysis, ultrasonic lysis and proteinase K lysis with CTAB, were used to extract the total DNA from compost. The detection performed on a nucleic acids and protein analyzer showed that all the three approaches produced high DNA yields. The agarose gel electrophoresis showed that the DNA fragments extracted from compost had a length of about 23 kb. A eubacterial 16S rRNA gene targeted primer pair (27F and 1 495R) was used for PCR amplification, and all the samples got almost the full length 16S rDNA sequence (about 1.5 kb). After digested by restriction endonucleases (Hae Ill and Alu I), the restriction map showed relatively identical microbial diversity in the DNA, which was extracted by the three different approaches. All the compost microbial DNA extracted by the three different approaches could be used for molecular ecological study, and researchers should choose the right approach for extracting microbial DNA from compost based on the facts.

  17. Microstructure and Properties of Solid-Liquid Composite Cast Hammer%固-液复合铸造锤头的组织与性能

    程巨强; 弥国华; 李梦; 刘志学


    研究高铬铸铁-碳钢固-液复合铸造锤头的组织及硬度分布特征。结果表明,固-液复合铸造高铬铸铁锤头部分具有较高的硬度,远离复合面高铬铸铁硬度增加,碳钢硬度降低。远离复合面高铬铸铁组织为M7C3型碳化物+回火马氏体+残余奥氏体,固-液复合铸造高铬铸铁组织中碳化物有定向分布的趋势,有利于提高锤头的耐磨性;远离复合面碳钢部分的组织为珠光体和较多的铁素体,复合面附近碳钢组织珠光体数量明显增加,铁素体数量明显减小,高铬铸铁中的碳通过复合界面向碳钢进行扩散。%It's a study on microstructure and hardness distribution characteristics of the solid-liquid composite cast hammer of high chromium cast iron and carbon steel casting. The experimental results have shown that high chromium cast iron of solid-liquid composite cast hammer has better hardness. Far away from composite surface, the hardness of high chromium cast iron hammer increased while that of carbon steel casting decreased and the microstructure was M7C3 type carbide+tempered martensite+residual austenite, and the carbide of solid-liquid composite high chromium cast iron hammer showed a trend of directional distribution propitious to an improved wear resistance. Far away from composite surface, the hardness of cast steel hammer decreased and with microstructure of pearlite and more ferrite. The number of pearlite significant increased and ferrite significant decreased near the composite surface and carbon in high chromium cast iron diffused from composite interface to carbon cast steel.

  18. Landslide stability analysis on basis of LIDAR data extraction

    Hu, Hui; Fernandez-Steeger, Tomas M.; Dong, Mei; Azzam, Rafig


    important role during surface construction for further more precise analysis purpose. 3D geological model can be built based on the connection between surface model and geological data like borehole data in GOCAD. Regarding the bench stability analysis, LEM (Limit Equilibrium Method) analysis using Janbu and FEM (Finite Element Method) have been adopted during this analyzing task. A program was developed to convert GOCAD 2D section data directly into the FEM software. The meshed model is then used for stability analysis. In one quarry, 3 cross sections have been extracted on basis of LIDAR original data (original 3 cross sections). To evaluate the advantages of LIDAR data for slope analysis, the results of safety factor (SF) were compared to simplified slope models as they are used normally. The comparison showed that variations of the SF reach up to 9%. Additionally, conservative evaluation demonstrated by SF results based on simplified model is not adaptive for decision making of filling.

  19. Flavonoids content in extracts secang (Caesalpinia Sappan L.) maceration method infundation analysis and visible ultraviolet spectrophotometer

    Youstiana Dwi Rusita; Suhartono


    .... Analysis using univariate analysis. This study shows that there are types of flavonoids flavones, flavonols and flavanols on extracts of Caesalpinia sappan L results maceration method, and there are flavonoid types of flavones...

  20. In-Situ Liquid Extraction and Analysis Platform for Mars and Ocean Worlds

    Kehl, F.; Wu, D.; Mora, M. F.; Creamer, J. S.; Willis, P. A.


    We present a compact sample extractor and analysis unit, based on subcritical water extraction and flow injection analysis, that could be used to support robotic missions seeking chemical signatures of life on Mars, Europa, Enceladus or Titan.

  1. Cleanup and analysis of sugar phosphates in biological extracts by using solid phase extraction and anion-exchange chromatography with pulsed amperometric detection

    Smith, Hans Peter; Cohen, A.; Buttler, T.


    A cleanup method based on anion-exchange solid-phase extraction (SPE) was developed to render biological extracts suitable for the analysis of hexose phosphates with a modified anion-exchange chromatography method and pulsed amperometric detection. The method was applied to cell extracts of Sacch......A cleanup method based on anion-exchange solid-phase extraction (SPE) was developed to render biological extracts suitable for the analysis of hexose phosphates with a modified anion-exchange chromatography method and pulsed amperometric detection. The method was applied to cell extracts...... of Saccharomyces cerevisiae obtained by using cold methanol as quenching agent and chloroform as extraction solvent. It was shown that pretreatment of the cell extract with SPE markedly improved the quality of the liquid chromatography analysis with recoveries of the sugar phosphates close to 100%. Furthermore...

  2. The decision to extract: part II. Analysis of clinicians' stated reasons for extraction.

    Baumrind, S; Korn, E L; Boyd, R L; Maxwell, R


    In a recently reported study, the pretreatment records of each subject in a randomized clinical trial of 148 patients with Class I and Class II malocclusions presenting for orthodontic treatment were evaluated independently by five experienced clinicians (drawn from a panel of 14). The clinicians displayed a higher incidence of agreement with each other than had been expected with respect to the decision as to whether extraction was indicated in each specific case. To improve our understanding of how clinicians made their decisions on whether to extract or not, the records of a subset of 72 subjects randomly selected from the full sample of 148, have now been examined in greater detail. In 21 of these cases, all five clinicians decided to treat without extraction. Among the remaining 51 cases, there were 202 decisions to extract (31 unanimous decision cases and 20 split decision cases). The clinicians cited a total of 469 reasons to support these decisions. Crowding was cited as the first reason in 49% of decisions to extract, followed by incisor protrusion (14%), need for profile correction (8%), Class II severity (5%), and achievement of a stable result (5%). When all the reasons for extraction in each clinician's decision were considered as a group, crowding was cited in 73% of decisions, incisor protrusion in 35%, need for profile correction in 27%, Class II severity in 15% and posttreatment stability in 9%. Tooth size anomalies, midline deviations, reduced growth potential, severity of overjet, maintenance of existing profile, desire to close the bite, periodontal problems, and anticipation of poor cooperation accounted collectively for 12% of the first reasons and were mentioned in 54% of the decisions, implying that these considerations play a consequential, if secondary, role in the decision-making process. All other reasons taken together were mentioned in fewer than 20% of cases. In this sample at least, clinicians focused heavily on appearance

  3. Chemical Analysis and Biological Activity of Jordanian Chamomile Extracts

    Nawal Hassan Al Bahtiti


    Full Text Available The Jordanian chamomile (Matricaria chamomilla has been researched more thoroughly to evaluate its useful properties. It is investigated and found that Jordanian chamomile is rich in phenolic compounds, with beneficial biological activities. By applying the most promising HPLC method, the content of total phenolics in methanolic extract was determined according to the Folin-Clocalteu procedure, and was found (GAE>20 mg/g. The flavonoid types were found as flavones and flavonolos.The minimum inhibitory concentration values for methanolic extracts of Jordanian chamomile were determined for different kinds of bacteria. The extracts have activity against Staphylococcus aurous, candida albicans, Esherichia Coli, Betula pubescens and Pinus sylvestris. The activity has been observed to be due to the tannins and a pigenin present in the extract. To utilize these significant sources of natural compounds, further characterization of phenolic composition is needed.

  4. [The extractive: life and death of an uncommon product of proximate analysis].

    Tomic, Sacha


    Issued from the pharmaceutical tradition, the "extractive", formerly "extract", is a typical artefact of proximate analysis introduced in the new nomenclature of 1787. After beign one of its most active promotors, Fourcroy published with Vauquelin a posthumous paper in 1810 in which he expressed some doubts about the substance. Theoretically present in almost all vegetable extracts, some chemists, pharmacists and physicians try to isolate the extractive without success and instead accumulated contradictory results. At the end, the eviction of this chimaera held by sceptical chemists such as Chevreul and Braconnot and the conversion of other analysts, dismissed extractive and the name almost gradually disappears at the begining of the 1830s.

  5. Analysis of human muscle extracts by proton NMR

    Venkatasubramanian, P.N.; Barany, M.; Arus, C.


    Perchloric acid extracts were prepared from pooled human muscle biopsies from patients diagnosed with scoliosis (SCOL) and cerebral palsy (CP). After neutralization with KOH and removal of perchlorate, the extracts were concentrated by freeze drying and dissolved in /sup 2/H/sub 2/O to contain 120 O.D. units at 280 nm per 0.5 ml. /sup 1/H NMR spectroscopy was performed with the 5 mm probe of a Varian XL300 instrument. Creatine, lactate, carnosine, and choline were the major resonances in the one-dimensional spectra of both extracts. With creatine as reference, 2.5-fold more lactate was found in SCOL than in CP, and a much smaller difference was also found in their carnosine content. Two-dimensional COSY comparison revealed several differences between the two extracts. Taurine, N-acetyl glutamate, glycerophosphoryl choline (or phosphoryl choline) and an unidentified spot were present only in the extract from SCOL but not in that from CP. On the other hand, aspartate, hydroxy-proline, carnitine and glycerophosphoryl ethanolamine were only present in CP but absent in SCOL. Alanine, cysteine, lysine and arginine appeared in both extracts without an apparent intensity difference.

  6. Pressurized water extraction of isoflavones by experimental design from soybean flour and Soybean Protein Isolate.

    Moras, Benjamin; Rey, Stéphane; Vilarem, Gérard; Pontalier, Pierre-Yves


    A Doehlert experimental design was conducted and surface response methodology was used to determine the effect of temperature, contact time and solid liquid ratio on isoflavone extraction from soybean flour or Soybean Protein Isolate in pressurized water system. The optimal conditions conducted gave an extraction yield of 85% from soybean flour. For Soybean Protein Isolate compared to soybean flour, the isoflavone extraction yield is 61%. This difference could be explained by higher aglycon content, while aglycon appears to be the least extracted isoflavone by pressurized water. The solid liquid ratio in the ASE cell was the overriding factor in obtaining high yields with both soybean products, while temperature has less influence. A high temperature causes conversion of the malonyls-glucosides and glucosides isoflavone derivatives into glucosides or aglycons forms. pressurized water extraction showed a high solubilization of protein material up to 95% of inserted Soybean Protein Isolate.

  7. Recovery of steroidal alkaloids from potato peels using pressurized liquid extraction.

    Hossain, Mohammad B; Rawson, Ashish; Aguiló-Aguayo, Ingrid; Brunton, Nigel P; Rai, Dilip K


    A higher yield of glycoalkaloids was recovered from potato peels using pressurized liquid extraction (1.92 mg/g dried potato peels) compared to conventional solid-liquid extraction (0.981 mg/g dried potato peels). Response surface methodology deduced the optimal temperature and extracting solvent (methanol) for the pressurized liquid extraction (PLE) of glycoalkaloids as 80 °C in 89% methanol. Using these two optimum PLE conditions, levels of individual steroidal alkaloids obtained were of 597, 873, 374 and 75 µg/g dried potato peel for α-solanine, α-chaconine, solanidine and demissidine respectively. Corresponding values for solid liquid extraction were 59%, 46%, 40% and 52% lower for α-solanine, α-chaconine, solanidine and demissidine respectively.

  8. Morphological instability of the solid-liquid interface under a thin shear flow with a free surface-ripples on icicles and stalactites

    Ueno, Kazuto


    Icicles and stalactites grow when their surfaces are covered with a thin film of flowing water through which latent heat of fusion and carbon dioxide are released to the surrounding air by diffusion and convection. Despite the complete difference in their basic growth mechanism, their surfaces often have ripples of centimeter-scale wavelengths. We consider the underlying common mechanism of ripple formation and find that the mean thickness of the water film and the capillary length associated with the surface tension of the water-air surface are common important characteristic lengths in determining the centimeter-scale wavelength of ripples. This is the first theoretical work on the morphological instability of solidification front during icicle and stalactite growth from a thin shear flow with one side being a free surface, in which we take into account the change of shape of the water-air surface when the shape of the solid-liquid interface is changed.

  9. Latent Heat storage characteristics of solid-liquid phase change Heat Storage Microcapsule Slurry by Boiling Heat Transfer under a Vacuum Condition

    Inaba, Hideo; Horibe, Akihiko; Haruki, Naoto; Katayama, Masatoshi; Manabe, Ken

    Recently, the new heat transfer medium, which fulfills both functions of heat storage and heat transportation, has been developed in ah eat storage field. Solid-liquid latent heat microcapsule slurry would correspond to the topical medium, so-called functionally thermal fluid. The preset study has clarified the latent heat storage characteristics of microcapsule slurry by making heat transfer enlargement with the help of slurry water pool boiling phenomenon. The paraffin wax at a melting point of 62°C was used as a phase change material which was packed into the microcapsule. The heating surface temperature and concentration of paraffin in the microcapsule slurry was selected as experimental parameters. As a result, the non-dimensional correlation equations of heat storage completion time and heat transfer were derived in terms of non-dimensional parameters.

  10. Analysis of PAHs in human serum using cloud point extraction and LC/MS

    Sirimanne, S.R.; Ma, Li; McClure, C. [National Center for Health, Environmental Health and Lab. Sciences, Atlanta, GA (United States)


    In these laboratories, the authors assess human exposure to environmental toxicants by quantifying the levels of target toxicants in serum of exposed individuals. The levels of target analytes are often in trace levels and hence preconcentration and cleanup are prerequisites to the analysis of these trace toxicants. The authors have identified cloud point extraction as an impressive alternative to conventional solvent extraction due its beneficial properties and the greater extraction efficiencies. The authors report for the first time, extraction of PAHs from human serum using cloud point technology and analysis by HPLC.

  11. Extraction optimization of catechins from green tea by using response surface analysis and its antibacterial activity to Escherichia coli%绿茶儿茶素醇提条件的响应曲面法优化及其抗大肠杆菌作用研究

    柯春林; 王永斌; 任茂生; 陶志杰; 曹珂珂; 唐莉


    The catechin from Huangshan Maofeng tea was extracted by using the ethanol extraction meth -od,the catechin yield was used as indicator .The influences of extraction temperature ,solid-liquid ratio and ethanol concentration on extraction were investigated .The result showed that the optimal extraction conditions were as follows:extraction temperature was 75.2 ℃,solid-liquid ratio was 1∶30.8 ( g/mL), ethanol concentration was 70.9%.Under the condition,the yield of 12.50%,and the antibacterial test showed that the extract of catechin have antibacterial effects to Escherichia coli.%采用乙醇浸提黄山毛峰绿茶,以儿茶素得率为指标,考察提取温度、料液比、乙醇浓度对提取效果的影响。结果表明,最佳提取工艺条件为:提取温度75.2℃,料液比1∶30.8(g/mL)和乙醇浓度70.9%。在此条件下,儿茶素得率12.50%。提取液对大肠杆菌生物被膜有抑制作用。

  12. Effects of various factors of ultrasonic treatment on the extraction recovery of drugs from fish tissues.

    Magiera, Sylwia; Pardylla, Anna; Baranowska, Irena


    In the present research, a combined extraction method of ultrasound-assisted extraction (UAE) in conjunction with solid phase extraction (SPE) was applied to isolation and enrichment of selected drugs (metoprolol, ticlopidine, propranolol, carbamazepine, naproxen, acenocumarol, diclofenac, ibuprofen) from fish tissues. The extracted analytes were separated and determined by ultra-high performance liquid chromatography with UV detection (UHPLC-UV) technique. The selectivity of the developed UHPLC-UV method was confirmed by comparison with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis. The important parameters, such as composition of type and pH of extraction solvent, solid/liquid rate volume of extraction solvent and number of extraction cycles were studied. The ultrasonic parameters, such as time, power and temperature of the process were optimized by using a half-fraction factorial central composite design (CCD). The mixture of 10 mL of methanol and 7 mL of water (pH 2.2) (three times) was chosen for the extraction of selected drug from fish tissues. The results showed that the highest recoveries of analytes were obtained with an extraction temperature of 40°C, ultrasonic power of 300 W, extraction time of 30 min. Under the optimal conditions, the linearity of method was 0.12-5.00 μg/g. The determination coefficients (R(2)) were from 0.979 to 0.998. The limits of detection (LODs) and limits of quantification (LOQs) for the extracted compounds were 0.04-0.17 μg/g and 0.12-0.50 μg/g, respectively. The recoveries were between 85.5% and 115.8%.

  13. A review of the extraction and chromatographic determination methods for the analysis of parabens.

    Piao, Chunying; Chen, Ligang; Wang, Yu


    Parabens are a family of most widely used antimicrobial preservatives in food ingredients, cosmetic consumer products and pharmaceutical preparations. But several recent studies have cautioned that exposure to parabens may have more harmful consequences on animal and human health than what we realized previously, which made the analysis of parabens necessary. In this paper, we reviewed main sample preparation methods and chromatographic analysis methods proposed in formerly published works dealing with the analysis of parabens in different matrices. The sample preparation methods included ultrasonic assisted extraction, supercritical fluid extraction, pressurized liquid extraction, solid phase extraction, solid phase microextraction, liquid phase microextraction, dispersive liquid-liquid microextraction, stir bar sorptive extraction and matrix solid phase dispersion. The chromatographic analysis methods involved liquid chromatography, gas chromatography, and capillary electrophoresis. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Analysis of the Interactions of Botanical Extract Combinations Against the Viability of Prostate Cancer Cell Lines

    Lynn S. Adams


    Full Text Available Herbal medicines are often combinations of botanical extracts that are assumed to have additive or synergistic effects. The purpose of this investigation was to compare the effect of individual botanical extracts with combinations of extracts on prostate cell viability. We then modeled the interactions between botanical extracts in combination isobolographically. Scutellaria baicalensis, Rabdosia rubescens, Panax-pseudo ginseng, Dendranthema morifolium, Glycyrrhiza uralensis and Serenoa repens were collected, taxonomically identified and extracts prepared. Effects of the extracts on cell viability were quantitated in prostate cell lines using a luminescent ATP cell viability assay. Combinations of two botanical extracts of the four most active extracts were tested in the 22Rv1 cell line and their interactions assessed using isobolographic analysis. Each extract significantly inhibited the proliferation of prostate cell lines in a time- and dose-dependent manner except repens. The most active extracts, baicalensis, D. morifolium, G. uralensis and R. rubescens were tested as two-extract combinations. baicalensis and D. morifolium when combined were additive with a trend toward synergy, whereas D. morifolium and R. rubescens together were additive. The remaining two-extract combinations showed antagonism. The four extracts together were significantly more effective than the two-by-two combinations and the individual extracts alone. Combining the four herbal extracts significantly enhanced their activity in the cell lines tested compared with extracts alone. The less predictable nature of the two-way combinations suggests a need for careful characterization of the effects of each individual herb based on their intended use.


    Zhang Zhong


    Full Text Available The objective of this study was to establish the optimum ultrasound-assisted extraction (UAE conditions for flavonoids from tartary buckwheat (FTB. Single factor experiments were performed to determine the appropriate range of extraction conditions and orthogonal experiment were performed to obtain the optimum extraction conditions. The results showed that the optimum UAE conditions for FTB were as followings: ethanol concentration of 65%, solid:liquid ratio of 1:40 g/ml, extraction time of 35 min and extraction temperature of 65 °C. UAE method is an alternative extraction technique for fast extraction of FTB.

  16. Gas chromatography-mass spectrometry analysis of various organic extracts ofMerremia borneensisfrom Sabah

    M Amzad Hossain; Muhammad Dawood Shah; Mahyar Sakari


    Objective:To analyse the chemical composition of different extracts ofMerremia borneensis (M. borneensis) by gas chromatography-mass spectrometry (GC-MS).Methods: The dried leaves powder was extracted with methanol at room temperature by using Soxhlet extractor. Methanol crude extracts ofM. borneensis were extrastel with hexane, chloroform, ethyl acetate and butanol. Results: Qualitative analyses of various organic crude extracts showed that majority of these are flavonoids, terpeniods, alkaloids and glycosides. Most of the identified compounds by GC-MS are biologically important. Further theM. borneensisleaf possesses certain characteristics that can be ascribed to cultivation on a domestic plantation.Conclusions: The suitable extracts for respective compounds can be chosen on the basis of aboveGC-MS analysis. All the major compounds from different extracts are biologically active molecules. Thus the identification of a good number of compounds from various extractsM. borneensis might have some ecological significance.

  17. Extraction of intracellular protein from Glaciozyma antarctica for proteomics analysis

    Faizura, S. Nor; Farahayu, K.; Faizal, A. B. Mohd; Asmahani, A. A. S.; Amir, R.; Nazalan, N.; Diba, A. B. Farah; Muhammad, M. Nor; Munir, A. M. Abdul


    Two preparation methods of crude extracts of psychrophilic yeast Glaciozyma antarctica were compared in order to obtain a good recovery of intracellular proteins. Extraction with mechanical procedures using sonication was found to be more effective for obtaining good yield compare to alkaline treatment method. The procedure is simple, rapid, and produce better yield. A total of 52 proteins were identified by combining both extraction methods. Most of the proteins identified in this study involves in the metabolic process including glycolysis pathway, pentose phosphate pathway, pyruyate decarboxylation and also urea cyle. Several chaperons were identified including probable cpr1-cyclophilin (peptidylprolyl isomerase), macrolide-binding protein fkbp12 and heat shock proteins which were postulate to accelerate proper protein folding. Characteristic of the fundamental cellular processes inferred from the expressed-proteome highlight the evolutionary and functional complexity existing in this domain of life.

  18. Thermal extraction analysis of five Los Azufres production wells

    Kruger, Paul; Quijano, Luis


    Thermal energy extraction from five wells supplying 5-MWe wellhead generators in three zones of the Los Azufres geothermal field has been examined from production and chemical data compiled over 14-years of operation. The data, as annual means, are useful in observing small-scale changes in reservoir performance with continuous production. The chemical components are chloride for quality control and the geothermometer elements for reservoir temperatures. The flowrate and fluid enthalpy data are used to calculate the thermal extraction rates. Integration of these data provides an estimate of the total energy extracted from the zone surrounding the well. The combined production and chemical geothermometer data are used to model the produced fluid as coming from just-penetrating wells for which the annual produced mass originates from a series of concentric hemispheric shells moving out into the reservoir. Estimates are made of the drawdown distance into the reservoir and the far-field conditions.

  19. Rapid method for the determination of 16 organochlorine pesticides in sesame seeds by microwave-assisted extraction and analysis of extracts by gas chromatography-mass spectrometry.

    Papadakis, Emmanouil N; Vryzas, Zisis; Papadopoulou-Mourkidou, Euphemia


    A method for the multiresidue analysis of 16 organochlorine insecticides in sesame seeds has been developed. The method is based on the microwave-assisted extraction (MAE) of the sesame seeds by the use of a water-acetonitrile mixture followed by Florisil clean-up of the extracts and subsequent analysis by gas chromatography-mass spectrometry (GC/MS) in the selected ion monitoring (SIM) mode. MAE operational parameters (extraction solvent, temperature and time, extractant volume) were optimized with respect to extraction efficiency of the target compounds from sesame seeds with 46% oil content. Recoveries >80% with relative standard deviations (RSD) seed samples imported to Greece.

  20. Phytochemical Analysis and Antioxidant Activity of Salvia chloroleuca Aerial Extracts

    Salimikia, Iraj; Reza Monsef-Esfahani, Hamid; Gohari, Ahmad Reza; Salek, Mehrnoosh


    Background Salvia, known as Maryam Goli in the Persian language, is an important genus that includes approximately 900 species in the Lamiaceae family. There are 58 Salvia species growing naturally in Iran, including Salvia chloroleuca Rech. f. and Allen., which grows wild in the northeastern and central parts of the country. Objectives This study was designed to determine the chemical composition, in vitro antioxidant activity, and total phenol content of various extracts of S. chloroleuca. Materials and Methods Dried aerial parts of the plant were crushed, then sequentially extracted with n-hexane, ethyl acetate, and methanol. The fractions of S. chloroleuca were subjected to silica gel column chromatography and Sephedex LH-20. The antioxidant activities of these extracts were measured by ferric reducing antioxidant power (FRAP), and the total phenolic contents of the extracts were evaluated using Folin-Ciocalteu reagent. Results The separation and purification processes were carried out using different chromatographic methods. Structural elucidation was on the basis 1H-NMR and 13C-NMR spectral data, in comparison with that reported in the literature. The isolated compounds were salvigenin (1), luteolin (2), cirsiliol (3), β-sitosterol (4), and daucosterol (5). Ethyl acetate extract displayed the highest level of total antioxidants and total polyphenols compared to the other analyzed extracts (n-hexane and methanol). In the FRAP assay, ethyl acetate extract had the highest (230.4±10.5) FRAP value, followed by methanol (211.4 ± 8.3) and n-hexane (143.4 ± 12.04). Total phenol contents were calculated to be 13.8 ± 0.3, 58.25 ± 0.05, and 43.48 ± 0.38 mg of gallic acid/100 g in the n-hexane, ethyl acetate, and methanol extracts, respectively. Conclusions The above-mentioned compounds were isolated for the first time from S. chloroleuca. The antioxidant activity of this plant could be in part related to isolated flavonoids and sterols. The results of this study

  1. Extraction, purification, methylation and GC-MS analysis of short-chain carboxylic acids for metabolic flux analysis.

    Tivendale, Nathan D; Jewett, Erin M; Hegeman, Adrian D; Cohen, Jerry D


    Dynamic metabolic flux analysis requires efficient and effective methods for extraction, purification and analysis of a plethora of naturally-occurring compounds. One area of metabolism that would be highly informative to study using metabolic flux analysis is the tricarboxylic acid (TCA) cycle, which consists of short-chain carboxylic acids. Here, we describe a newly-developed method for extraction, purification, derivatization and analysis of short-chain carboxylic acids involved in the TCA cycle. The method consists of snap-freezing the plant material, followed by maceration and a 12-15h extraction at -80 °C. The extracts are then subject to reduction (to stabilize β-keto acids), purified by strong anion exchange solid phase extraction and methylated with methanolic HCl. This method could also be readily adapted to quantify many other short-chain carboxylic acids.

  2. 板栗苞中栲胶提取工艺的研究%Study on tannin extract from chestnut (Castanea mollissima Blume) shell

    王丽卫; 孙健; 王岩; 赵兵


    Objective To obtain the optimum extraction parameters of tannin extract from chestnut shell. Methods Based on single-factor test, uniform experimental design with 4-factor and 3-level was adopted to study the effects ofparticle size, concentration of acetone solution, solid-liquid ratio and ultrasonic power on the extraction rate of tannin extract. Using partial least squares regression analysis, the optimal extraction parameters were obtained. Component of tannin extract was also analyzed by hide powder method.Results The optimum conditions of tannin extract from chestnut shell were as follows: particle size was 100 meshes, 50% acetone solution, solid-liquid ratio was 1:18 and ultrasonic power was 400 W. Under this condition, the extraction rate of tannin extract was 31.28%, the content of tannin was 63.68%, the pH value was 3.81 and the total color value was 22.Conclusion The tannin extract from chestnut shell has reached the standard of cold-soluble valonea extraction, which illustrated the feasibility of using chestnut shell as a kind of material for tannin extract.%目的:以板栗苞为原料,研究板栗苞提取栲胶的最佳工艺。方法在粉碎粒度、丙酮溶液浓度、料液比和超声功率单因素实验基础上,以栲胶提取率为响应值,设计4因素3水平的均匀实验,通过均匀设计偏最小二乘回归建模分析,得出最优指标时各个因素组合参数,并采用铬皮粉法对最优条件下提取的栲胶进行分析。结果板栗苞中栲胶提取的最佳工艺为:粉碎粒度100目,50%丙酮溶液,料液比1:18,超声功率400 W,在此条件下,栲胶提取率为31.28%,单宁含量为63.68%, pH值为3.81,总色值为22。结论以板栗苞为原料提椀取的栲胶达到了橡栲胶冷溶合格品的指标,说明板栗苞提取栲胶的工艺可行性。

  3. Determination of total antioxidant capacity of humic acids using CUPRAC, Folin-Ciocalteu, noble metal nanoparticle- and solid-liquid extraction-based methods.

    Karadirek, Şeyda; Kanmaz, Nergis; Balta, Zeynep; Demirçivi, Pelin; Üzer, Ayşem; Hızal, Jülide; Apak, Reşat


    Total antioxidant capacity (TAC) of humic acid (HA) samples was determined using CUPRAC (CUPric Reducing Antioxidant Capacity), FC (Folin-Ciocalteu), QUENCHER-CUPRAC, QUENCHER-FC, Ag-NP (Silver nanoparticle)‒ and Au-NP (Gold nanoparticle)‒based methods. Conventional FC and modified FC (MFC) methods were applied to solid samples. Because of decreased solubility of Folin-Ciocalteu's phenol reagent in organic solvents, solvent effect on TAC measurement was investigated using QUENCHER-CUPRAC assay by using ethanol:distilled water and dimethyl sulfoxide:distilled water with varying ratios. To see the combined effect of solubilization (leaching) and TAC measurement of humic acids simultaneously, QUENCHER experiments were performed at 25°C and 50°C; QUENCHER-CUPRAC and QUENCHER-FC methods agreed well and had similar precision in F-statistics. Although the Gibbs free energy change (ΔG°) of the oxidation of HA dihydroxy phenols with the test reagents were negative, the ΔG° was positive only for the reaction of CUPRAC reagent with isolated monohydric phenols, showing CUPRAC selectivity toward polyphenolic antioxidants. This is the first work on the antioxidant capacity measurement of HA having a sparingly soluble matrix where enhanced solubilization of bound phenolics is achieved with coupled oxidation by TAC reagents.

  4. Flavonoids content in extracts secang (Caesalpinia Sappan L. maceration method infundation analysis and visible ultraviolet spectrophotometer

    Youstiana Dwi Rusita


    Full Text Available Secang (Caesalpinia sappan L has a component of a chemical compound essential oils, flavonoids, benzopyran, sapanin, brazilin, caesalpin S, caesalpin P, sapanon A, sapanon B. Flavonoids are chemical components that can be used in medical and industrial fields. This study aimed to determine the levels of flavonoids contained in extracts secang results maceration and extraction methods infundation. This study used quantitative and descriptive research design. This study using purposive sampling with two sample of Caesalpinia sappan L extract result of infundation and maceration. Analysis using univariate analysis. This study shows that there are types of flavonoids flavones, flavonols and flavanols on extracts of Caesalpinia sappan L results maceration method, and there are flavonoid types of flavones, flavonols and flavanols on extracts of Caesalpinia sappan L results infundation method. Flavonoid content test results showed that the levels of flavonoids in extracts of Caesalpinia sappan L results maceration 0.0539% whereas the levels of flavonoids in the extract of Caesalpinia sappan L results infundation methods 0.1902%. Necessary standardization of botanicals Caesalpinia sappan L to determine the levels of flavonoids using ultraviolet visible spectrophotometer, and the analysis of the levels of flavonoids in the extract of Caesalpinia sappan L using different solvents. As a follow-up is necessary to design the manufacture of dosage formulations of the active ingredient flavanoid compounds from the extract of Caesalpinia sappan L.

  5. Protective efficacy of Solanum xanthocarpum root extracts against free radical damage: phytochemical analysis and antioxidant effect.

    Kumar, S; Sharma, U K; Sharma, A K; Pandey, A K


    Free radicals have been implicated in many diseases. They attack biological macromolecules in healthy human cells and cause protein and DNA damage along with lipid peroxidation. Present study reports the phytochemical analysis as well as free radical scavenging and antioxidant activities of Solanum xanthocarpum root extracts. Tannins, flavonoids, terpenoids, alkaloids, saponins and steroids were present in different extracts. Total flavonoid content in extracts was quantified and maximum contents were found in ethyl acetate fraction followed by chloroform and ethyl alcohol fractions, respectively. Dose dependent response was observed in metal ion chelating activity of extracts. Comparatively better chelating activity was found in polar extracts. Most of the extracts exhibited significant free radical scavenging activity in DPPH radical scavenging assay. Ethanolic and aqueous extracts accounted for about 40—50% lipid peroxidation inhibition (LPOI) in rat liver homogenate. Antioxidant activity did not show direct correlation with the amount of flavonoid contents in the extracts. However, direct correlation was observed between DPPH free radical scavenging activity and LPOI. Antioxidant activity of the extracts was compared with standard antioxidants. The differential activity observed in extracts could be attributed to the presence of other phytochemicals such as tannins and terpenoids in addition to flavonoids. The study demonstrated appreciable protective efficacy in S. xanthocarpum root extracts against free radical damage.

  6. Acetonitrile extraction and dual-layer solid phase extraction clean-up for pesticide residue analysis in propolis.

    Oellig, Claudia


    Propolis is a very complex mixture of substances that is produced by honey bees and is known to be a rather challenging matrix for residue analysis. Besides resins, flavonoids and phenols, high amount of wax is co-extracted resulting in immense matrix effects. Therefore a suitable clean-up is crucial and indispensable. In this study, a reliable solid phase extraction (SPE) clean-up was developed for pesticide residue analysis in propolis. The clean-up success was quickly and easily monitored by high-performance thin-layer chromatography with different detection possibilities. The final method consists of the extraction of propolis with acetonitrile according to the QuEChERS method followed by an effective extract purification on dual-layer SPE cartridges with spherical hydrophobic polystyrene-divinylbenzene resin/primary secondary amine as sorbent and a mixture of toluene/acetone (95:5, v/v) for elution. Besides fat-soluble components like waxes, flavonoids, and terpenoids, more polar compounds like organic acids, fatty acids, sugars and anthocyanins were also removed to large extent. Method performance was assessed by recovery experiments at spiking levels of 0.5 and 1mg/kg (n=5) for fourteen pesticides that are relevant for propolis. Mean recoveries determined by HPLC-MS against solvent standards were between 40 and 101%, while calculation against matrix-matched standards provided recoveries of 79-104%. Precision of recovery, assessed by relative standard deviations, were below 9%. Thus, the developed dual-layer SPE clean-up enables the reliable pesticide residue analysis in propolis and provides a suitable alternative to time-consuming clean-up procedures proposed in literature.

  7. Local kernel nonparametric discriminant analysis for adaptive extraction of complex structures

    Li, Quanbao; Wei, Fajie; Zhou, Shenghan


    The linear discriminant analysis (LDA) is one of popular means for linear feature extraction. It usually performs well when the global data structure is consistent with the local data structure. Other frequently-used approaches of feature extraction usually require linear, independence, or large sample condition. However, in real world applications, these assumptions are not always satisfied or cannot be tested. In this paper, we introduce an adaptive method, local kernel nonparametric discriminant analysis (LKNDA), which integrates conventional discriminant analysis with nonparametric statistics. LKNDA is adept in identifying both complex nonlinear structures and the ad hoc rule. Six simulation cases demonstrate that LKNDA have both parametric and nonparametric algorithm advantages and higher classification accuracy. Quartic unilateral kernel function may provide better robustness of prediction than other functions. LKNDA gives an alternative solution for discriminant cases of complex nonlinear feature extraction or unknown feature extraction. At last, the application of LKNDA in the complex feature extraction of financial market activities is proposed.

  8. Evaluation of sample extraction methods for proteomics analysis of green algae Chlorella vulgaris.

    Gao, Yan; Lim, Teck Kwang; Lin, Qingsong; Li, Sam Fong Yau


    Many protein extraction methods have been developed for plant proteome analysis but information is limited on the optimal protein extraction method from algae species. This study evaluated four protein extraction methods, i.e. direct lysis buffer method, TCA-acetone method, phenol method, and phenol/TCA-acetone method, using green algae Chlorella vulgaris for proteome analysis. The data presented showed that phenol/TCA-acetone method was superior to the other three tested methods with regards to shotgun proteomics. Proteins identified using shotgun proteomics were validated using sequential window acquisition of all theoretical fragment-ion spectra (SWATH) technique. Additionally, SWATH provides protein quantitation information from different methods and protein abundance using different protein extraction methods was evaluated. These results highlight the importance of green algae protein extraction method for subsequent MS analysis and identification.

  9. User-oriented summary extraction for soccer video based on multimodal analysis

    Liu, Huayong; Jiang, Shanshan; He, Tingting


    An advanced user-oriented summary extraction method for soccer video is proposed in this work. Firstly, an algorithm of user-oriented summary extraction for soccer video is introduced. A novel approach that integrates multimodal analysis, such as extraction and analysis of the stadium features, moving object features, audio features and text features is introduced. By these features the semantic of the soccer video and the highlight mode are obtained. Then we can find the highlight position and put them together by highlight degrees to obtain the video summary. The experimental results for sports video of world cup soccer games indicate that multimodal analysis is effective for soccer video browsing and retrieval.

  10. Response Surface Methodology for Optimization of Hot Reflux Extraction of Xanthohumol from Humulus lupulus%响应面法优化黄腐酚提取工艺条件的研究

    赵书艺; 王昌禄; 陈勉华; 王玉荣; 李风娟; 杨华; 李贞景


    To optimize the extraction of xanthohumol from residue of CO2 extraction of hops by hot reflux, the response surface method was used based on the single factor test. According to the Box-Behnken statistical design and response surface analysis, the model was drawn between the extraction rate of xanthohumol and extraction time, temperature, solvent and solid-liquid ratio. The optimum conditions were determined as follows: extraction solvent of 96% alcohol, temperature of 60 ℃, time of 88 min, solid-liquid ratio of 1:26 (g · mL-1). The yield of xanthohumol was up to 4. 05% with the purity of 12. 31%.%以啤酒花超临界CO2萃取物剩余残渣为原料,利用响应面法对热回流提取黄腐酚的工艺条件进行了优化.以单因素实验为基础,根据中心组合设计原理,采用响应面分析法,对提取时间、提取温度、提取溶剂、料液比各因子间显著性和交互作用进行分析,得到黄腐酚提取的最佳工艺条件为:乙醇体积分数96%,提取温度为60℃,提取时间为88 min,提取料液比为1 g∶26 mL,在该条件下,黄腐酚得率可达4.05%,纯度为12.31%.

  11. Methodology of data extraction from a corpus for the conceptual analysis of metaphor in legal English

    Kucheruk, Liliya


    The present paper entitled “Methodology of data extraction from a corpus for the conceptual analysis of metaphor in legal English” investigates the main approaches to the study of metaphor in legal language from the point of view of cognitive linguistics. It also offers the most widely spread methods of data extraction form a corpus.


    A. A. Chakhirova


    Full Text Available The article presents studies on development of cosmetics with complex extracts from herb of Bidens, flowers of Calendula, and flowers of Matricaria. We cited the analysis methods of the received extract and a drug on its base

  13. Analysis of heavy metals and fluoride in vegetation by extraction with concentrated mineral acids.

    Johnson, M S


    A rapid potentiometric method for determining fluoride in vegetation is described. Recovery of flouride by extraction with concentrated mineral acids compares favourably with standard methods of analysis in terms of accuracy and precision. The procedure affords the additional advantage that several citations are also quantitatively extracted and may be determined directly in the acid digest by atomic absorption spectrophotometry.

  14. Extraction and determination of molybdenum with tributyl phosphate Application to analysis of copper-molybdenum ores.

    Caiozzi, M; Zunino, H; Sepúlveda, L


    A differential spectrophotometric method is described for the determination of molybdenum by means of solvent extraction with tributylphosphate of the peroxymolybdate complex formed with H(2)O(2) in 3.5N H(2)SO(4). The extraction parameters are studied, and the behaviour of some other ions is reported. The method is used for ore analysis.

  15. Optimization of microwave assisted extraction of pectin from orange peel.

    Prakash Maran, J; Sivakumar, V; Thirugnanasambandham, K; Sridhar, R


    In this study, microwave-assisted extraction was applied for pectin extraction from the dried orange peel and Box-Behnken response surface design was used to study and optimize the effects of processing variables (microwave power, irradiation time, pH and solid-liquid ratio) on the yield of pectin. The amount of pectin extracted increased with increasing microwave power, while it reduces as the time, pH and solid-liquid ratio increased. From the results, second order polynomial model was developed and it adequately explained the data variation and significantly represented the actual relationship between independent variables and the response. An optimization study using Derringer's desired function methodology was performed and optimal conditions based on both individual and combinations of all independent variables (microwave power of 422W, irradiation time of 169 s, pH of 1.4 and solid-liquid ratio of 1:16.9 g/ml) were determined with maximum pectin yield of 19.24%, which was confirmed through validation experiments.

  16. A one dimensional model for the prediction of extraction yields in a two phases modified twin-screw extruder


    Solid/liquid extraction is performed on raw plant substrate with a modified twin-screw extruder (TSE) used as a thermo-mecanochemical reactor. Visual observations and experimental residence time distributions (RTD) are used to develop a solid transport model based on classical chemical engineering method. Modeled and experimental residence times are compared. The transport model is then coupled with a reactive extraction model in order to predict extraction yields.

  17. Comparison of DNA extraction methods for meat analysis.

    Yalçınkaya, Burhanettin; Yumbul, Eylem; Mozioğlu, Erkan; Akgoz, Muslum


    Preventing adulteration of meat and meat products with less desirable or objectionable meat species is important not only for economical, religious and health reasons, but also, it is important for fair trade practices, therefore, several methods for identification of meat and meat products have been developed. In the present study, ten different DNA extraction methods, including Tris-EDTA Method, a modified Cetyltrimethylammonium Bromide (CTAB) Method, Alkaline Method, Urea Method, Salt Method, Guanidinium Isothiocyanate (GuSCN) Method, Wizard Method, Qiagen Method, Zymogen Method and Genespin Method were examined to determine their relative effectiveness for extracting DNA from meat samples. The results show that the salt method is easy to perform, inexpensive and environmentally friendly. Additionally, it has the highest yield among all the isolation methods tested. We suggest this method as an alternative method for DNA isolation from meat and meat products. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Microprobe analysis of brine shrimp grown on meteorite extracts

    Kennedy, J. [National Isotope Centre, GNS Science, 30 Gracefield Road, Lower Hutt (New Zealand)]. E-mail:; Mautner, M.N. [Soil, Plant and Ecological Sciences Division, Lincoln University (New Zealand) and Department of Chemistry, University of Canterbury, Christchurch 8001 (New Zealand)]. E-mail:; Barry, B. [National Isotope Centre, GNS Science, 30 Gracefield Road, Lower Hutt (New Zealand); Markwitz, A. [National Isotope Centre, GNS Science, 30 Gracefield Road, Lower Hutt (New Zealand)


    Nuclear microprobe methods have been used to investigate the uptake and distribution of various elements by brine shrimps and their unhatched eggs when grown in extracts of the Murchison and Allende carbonaceous meteorites, which were selected as model space resources. Measurements were carried out using a focussed 2 MeV proton beam raster scanned over the samples in order to obtain the average elemental concentrations. Line scans across the egg and shrimp samples show uptake of elements such as Mg, Ni, S and P which are present in the meteorites. The results confirmed that carbonaceous chondrite materials can provide nutrients, including high levels of the essential nutrient phosphate. The concentrations of these elements varied significantly between shrimp and eggs grown in extracts of the two meteorite types, which can help in identifying optimal growth media. Our results illustrate that nuclear microprobe techniques can determine elemental concentrations in organisms exposed to meteorite derived media and thus help in identifying useful future resources.

  19. Model analysis of mechanisms controlling pneumatic soil vapor extraction

    Høier, Camilla Kruse; Sonnenborg, Torben Obel; Jensen, Karsten Høgh;


    The efficiency of traditional soil venting or soil vapor extraction (SVE) highly depends on the architecture of the subsurface because imposed advective air flow tends to bypass low-permeable contaminated areas. Pneumatic SVE is a technique developed to enhance remediation efficiency of heterogen...... level the pneumatic venting technology is superior to the traditional technique, and that the method is particularly efficient in cases where large permeability contrasts exist between soil units in the subsurface.......The efficiency of traditional soil venting or soil vapor extraction (SVE) highly depends on the architecture of the subsurface because imposed advective air flow tends to bypass low-permeable contaminated areas. Pneumatic SVE is a technique developed to enhance remediation efficiency...... of heterogeneous soils by enforcing large fluctuating pressure fronts through the contaminated area. Laboratory experiments have suggested that pneumatic SVE considerably improves the recovery rate from low-permeable units. We have analyzed the experimental results using a numerical code and quantified...

  20. Gas chromatography-mass spectroscopy analysis of bioactive petalostigma extracts: Toxicity, antibacterial and antiviral activities

    F R Kalt


    Full Text Available Background: Petalostigma pubescens and Petalostigma triloculare were common components of pharmacopeia′s of multiple Australian Aboriginal tribal groupings which traditionally inhabited the areas in which they grow. Among these groups, they had a myriad of medicinal uses in treating a wide variety of bacterial, fungal and viral infections. This study was undertaken to test P. pubescens and P. triloculare leaf and fruit extracts for the ability to inhibit bacterial and viral growth and thus validate Australian Aboriginal usage of these plants in treating bacterial and fungal diseases. Materials and Methods: P. pubescens, and P. triloculare leaves and fruit were extracted and tested for antimicrobial, antiviral activity and toxicity. The bioactive extracts were further examined by RP-HPLC and GC-MS to identify the component compounds. Results: The methanol, water and ethyl acetate leaf and fruit extracts of displayed potent antibacterial activity. The methanol and ethyl acetate extracts displayed the broadest specificity, inhibiting the growth of 10 of the 14 bacteria tested (71% for the leaf extract and 9 of the 14 bacteria tested (64% for the fruit extracts. The water extracts also had broad spectrum antibacterial activity, inhibiting the growth of 8 (57% and 7 (50% of the 14 bacteria tested, respectively. All antibacterial extracts were approximately equally effective against Gram-positive and Gram-negative bacteria, inhibiting the growth of 50-75% of the bacteria tested. The methanol, water and ethyl acetate extracts also displayed antiviral activity in the MS2 plaque reduction assay. The methanol and water extracts inhibited 26.6-49.0% and 85.4-97.2% of MS2 plaque formation, respectively, with the fruit extracts being more potent inhibitors. All ethyl acetate extracts inhibited 100% of MS2 plaque formation. All extracts were also non-toxic or of low toxicity. Analysis of these extracts by RP-HPLC showed that the P. triloculare ethyl acetate

  1. Cluster Analysis of Customer Reviews Extracted from Web Pages

    S. Shivashankar


    Full Text Available As e-commerce is gaining popularity day by day, the web has become an excellent source for gathering customer reviews / opinions by the market researchers. The number of customer reviews that a product receives is growing at very fast rate (It could be in hundreds or thousands. Customer reviews posted on the websites vary greatly in quality. The potential customer has to read necessarily all the reviews irrespective of their quality to make a decision on whether to purchase the product or not. In this paper, we make an attempt to assess are view based on its quality, to help the customer make a proper buying decision. The quality of customer review is assessed as most significant, more significant, significant and insignificant.A novel and effective web mining technique is proposed for assessing a customer review of a particular product based on the feature clustering techniques, namely, k-means method and fuzzy c-means method. This is performed in three steps : (1Identify review regions and extract reviews from it, (2 Extract and cluster the features of reviews by a clustering technique and then assign weights to the features belonging to each of the clusters (groups and (3 Assess the review by considering the feature weights and group belongingness. The k-means and fuzzy c-means clustering techniques are implemented and tested on customer reviews extracted from web pages. Performance of these techniques are analyzed.


    J Živković


    Full Text Available Proanthocyanidins, also known as condensed tannins are widespread in woody plants, but are also found in certain forages. Castanea sativa Mill. are exploited for various purposes, but a little is known about potential of this species and possible application in diet and therapy. The parts of chestnut such as: seed, peeled seed, brown seed shell, red internal seed shell, leaves, catkin, spiny bur, as well as the new and old chestnut bark were extracted with 50% ethanol as an extragents. Contents of total phenolics and total flavonoids were measured by application of the standard colorimetric assay. The total condensed tannins content estimated was highest in red internal seed shell 15.29%CE (vanillin assay and 3.12%CT (acid butanol assay. Also high content of total phenolic compounds and condensed tannins had extracts of catkin, brown seed shell of chestnut and new chestnut bark. Extracts of C. sativa Mill. can be a potential resource of natural tannins with possible application in diet and therapy.

  3. Analysis of entropy extraction efficiencies in random number generation systems

    Wang, Chao; Wang, Shuang; Chen, Wei; Yin, Zhen-Qiang; Han, Zheng-Fu


    Random numbers (RNs) have applications in many areas: lottery games, gambling, computer simulation, and, most importantly, cryptography [N. Gisin et al., Rev. Mod. Phys. 74 (2002) 145]. In cryptography theory, the theoretical security of the system calls for high quality RNs. Therefore, developing methods for producing unpredictable RNs with adequate speed is an attractive topic. Early on, despite the lack of theoretical support, pseudo RNs generated by algorithmic methods performed well and satisfied reasonable statistical requirements. However, as implemented, those pseudorandom sequences were completely determined by mathematical formulas and initial seeds, which cannot introduce extra entropy or information. In these cases, “random” bits are generated that are not at all random. Physical random number generators (RNGs), which, in contrast to algorithmic methods, are based on unpredictable physical random phenomena, have attracted considerable research interest. However, the way that we extract random bits from those physical entropy sources has a large influence on the efficiency and performance of the system. In this manuscript, we will review and discuss several randomness extraction schemes that are based on radiation or photon arrival times. We analyze the robustness, post-processing requirements and, in particular, the extraction efficiency of those methods to aid in the construction of efficient, compact and robust physical RNG systems.

  4. The GC/MS Analysis of Volatile Components Extracted by Different Methods from Exocarpium Citri Grandis

    Zhisheng Xie


    Full Text Available Volatile components from Exocarpium Citri Grandis (ECG were, respectively, extracted by three methods, that is, steam distillation (SD, headspace solid-phase microextraction (HS-SPME, and solvent extraction (SE. A total of 81 compounds were identified by gas chromatography-mass spectrometry including 77 (SD, 56 (HS-SPME, and 48 (SE compounds, respectively. Despite of the extraction method, terpenes (39.98~57.81% were the main volatile components of ECG, mainly germacrene-D, limonene, 2,6,8,10,14-hexadecapentaene, 2,6,11,15-tetramethyl-, (E,E,E-, and trans-caryophyllene. Comparison was made among the three methods in terms of extraction profile and property. SD relatively gave an entire profile of volatile in ECG by long-time extraction; SE enabled the analysis of low volatility and high molecular weight compounds but lost some volatiles components; HS-SPME generated satisfactory extraction efficiency and gave similar results to those of SD at analytical level when consuming less sample amount, shorter extraction time, and simpler procedure. Although SD and SE were treated as traditionally preparative extractive techniques for volatiles in both small batches and large scale, HS-SPME coupled with GC/MS could be useful and appropriative for the rapid extraction and qualitative analysis of volatile components from medicinal plants at analytical level.

  5. Comparison of different extraction solutions for the analysis of allergens in hen's egg.

    Hildebrandt, S; Steinhart, H; Paschke, A


    An important requirement for the correct procedure of allergen analysis in hen's egg is to obtain complete and unaltered protein extracts. Besides the aim of a quantitative extraction of the allergens from the matrix, it is equally important not to alter their allergenic potential during the extraction process. This paper describes and compares six extraction solutions for the analysis of whole-egg proteins and allergens. These requirements were examined via protein determination according to Bradford [Bradford, M. M. (1976). Rapid and sensitive method for quantitation of microgram quantities of protein utilizing principle of protein-dye binding. Analytical Biochemistry, 72, 248-254] and Kjeldahl [Meyer, A. H. (2006). Lebensmittelrecht, Verlag C.H. Beck München, Stand: 1. February 2006, § 64, Lebensmittel- und Futtermittelgesetzbuch, Amtliche Sammlung von Untersuchungsmethoden, Nr. L 06.00-7] as well as the EAST-inhibition method. It could be demonstrated that the extraction with a urea solution (8M) led to significant interferences during the protein determination, and substantially reduced the allergenic potential of egg proteins. With all other extraction solutions adequate protein contents could be extracted. The highest protein content was achieved by the extraction with phosphate buffered saline followed by a Tween 20 solution, physiological saline, water, and acetate buffer. The results show that none of these extracts - except for the urea solution (8M) - was altered in its' allergenic potential.


    Parixit Bhandurge


    Full Text Available Fenugreek (Trigonella foenum-graecumL. Leguminosae is widely used in Indian Ayurvedic medicine for the treatment of diabetes mellitus. Antihyperglycaemic effect of the two different doses (200 and 400 mg/kg of the fenugreek extract was evaluated in this study. Blood glucose, liver profile, renal profile and total lipid levels were determined in alloxan induced diabetic rats after oral administration of a fenugreek extract. A comparable hypoglycemic effect was evidenced from the data obtained after 7 and 21 days of oral administration of the extract. The extract lowered the total cholesterol and serum triglycerides. Histopathological analysis of pancreas showed normal acini, and normal cellular in the islets of langerhans in the pancreas of normal control and Extensive damage to islets of langerhans and reduced dimensions of islets in alloxan induced diabetes. Restoration of islets of langerhans seen in diabetic rats treated with fenugreek extract. The results of this study clearly shows the hypoglycaemic activity of the extract

  7. Background Extraction Method Based on Block Histogram Analysis for Video Image

    Li Hua; Peng Qiang


    A novel method of histogram analysis for background extraction in video image is proposed, which is derived from the pixelbased histogram analysis. Not only the statistical property of pixels between temporal frames, but also the correlation of local pixels in a single frame is exploited in this method. When carrying out histogram analysis for background extraction, the proposed method is not based on a single pixel but on a 2×2 block that has much less computational quantities and can extract a sound background image from video sequence simultaneously. A comparative experiment between the proposed method and the pixel-based histogram analysis shows that the proposed method has a faster speed in background extraction and the obtained background image is better in quantity.

  8. Application of supercritical fluid carbon dioxide to the extraction and analysis of lipids.

    Lee, Jae Won; Fukusaki, Eiichiro; Bamba, Takeshi


    Supercritical carbon dioxide (SCCO(2)) is an ecofriendly supercritical fluid that is chemically inert, nontoxic, noninflammable and nonpolluting. As a green material, SCCO(2) has desirable properties such as high density, low viscosity and high diffusivity that make it suitable for use as a solvent in supercritical fluid extraction, an effective and environment-friendly analytical method, and as a mobile phase for supercritical fluid chromatography, which facilitates high-throughput, high-resolution analysis. Furthermore, the low polarity of SCCO(2) is suitable for the extraction and analysis of hydrophobic compounds. The growing concern surrounding environmental pollution has triggered the development of green analysis methods based on the use of SCCO(2) in various laboratories and industries. SCCO(2) is becoming an effective alternative to conventional organic solvents. In this review, the usefulness of SCCO(2) in supercritical fluid extraction and supercritical fluid chromatography for the extraction and analysis of lipids is described.

  9. Performance analysis of a hybrid fingerprint extracted from optical coherence tomography fingertip scans

    Darlow, Luke N


    Full Text Available International Conference on Biometrics (ICB), 13-16 June 2016, Halmstad, Sweden Performance analysis of a hybrid fingerprint extracted from optical coherence tomography fingertip scans Darlow LN Connan J Singh A ABSTRACT: The Hybrid fingerprint is a...

  10. Optimal Fixation Conditions and DNA Extraction Methods for MLPA Analysis on FFPE Tissue-Derived DNA.

    Atanesyan, Lilit; Steenkamer, Maryvonne J; Horstman, Anja; Moelans, Cathy B; Schouten, Jan P; Savola, Suvi P


    Molecular genetic analysis of formalin-fixed, paraffin-embedded (FFPE) tissues is of great importance both for research and diagnostics. Multiplex ligation-dependent probe amplification (MLPA) is a widely used technique for gene copy number determination, and it has been successfully used for FFPE tissue-extracted DNA analysis. However, there have been no studies addressing the effect of tissue fixation procedures and DNA extraction methods on MLPA. This study therefore focuses on selecting optimal preanalytic conditions such as FFPE tissue preparation conditions and DNA extraction methods. Healthy tissues were fixed in buffered or nonbuffered formalin for 1 hour, 12 to 24 hours, or 48 to 60 hours at 4 °C or at room temperature. DNA extracted from differently fixed and subsequently paraffin-embedded tissues was used for MLPA. Four commercial DNA extraction kits and one in-house method were compared. Tissues fixed for 12 to 24 hours in buffered formalin at room temperature produced DNA with the most optimal quality for MLPA. The in-house FFPE DNA extraction method was shown to perform as efficient as or even superior to other methods in terms of suitability for MLPA, time and cost-efficiency, and ease of performance. FFPE-extracted DNA is well suitable for MLPA analysis, given that optimal tissue fixation and DNA extraction methods are chosen.

  11. Ultra-low temperature (≤300 °C) growth of Ge-rich SiGe by solid-liquid-coexisting annealing of a-GeSn/c-Si structures

    Sadoh, Taizoh; Chikita, Hironori; Matsumura, Ryo; Miyao, Masanobu


    Ultra-low temperature (≤300 °C) growth of Ge-rich SiGe on Si substrates is strongly desired to realize advanced electronic and optical devices, which can be merged onto Si large-scale integrated circuits (LSI). To achieve this, annealing characteristics of a-GeSn/c-Si structures are investigated under wide ranges of the initial Sn concentrations (0%-26%) and annealing conditions (300-1000 °C, 1 s-48 h). Epitaxial growth triggered by SiGe mixing is observed after annealing, where the annealing temperatures necessary for epitaxial growth significantly decrease with increasing initial Sn concentration and/or annealing time. As a result, Ge-rich (˜80%) SiGe layers with Sn concentrations of ˜2% are realized by ultra-low temperature annealing (300 °C, 48 h) for a sample with the initial Sn concentration of 26%. The annealing temperature (300 °C) is in the solid-liquid coexisting temperature region of the phase diagram for Ge-Sn system. From detailed analysis of crystallization characteristics and composition profiles in grown layers, it is suggested that SiGe mixing is generated by a liquid-phase reaction even at ultra-low temperatures far below the melting temperature of a-GeSn. This ultra-low-temperature growth technique of Ge-rich SiGe on Si substrates is expected to be useful to realize next-generation LSI, where various multi-functional devices are integrated on Si substrates.

  12. Ultra-low temperature (≤300 °C) growth of Ge-rich SiGe by solid-liquid-coexisting annealing of a-GeSn/c-Si structures

    Sadoh, Taizoh, E-mail:; Chikita, Hironori; Miyao, Masanobu [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Matsumura, Ryo [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); JSPS Research Fellow, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083 (Japan)


    Ultra-low temperature (≤300 °C) growth of Ge-rich SiGe on Si substrates is strongly desired to realize advanced electronic and optical devices, which can be merged onto Si large-scale integrated circuits (LSI). To achieve this, annealing characteristics of a-GeSn/c-Si structures are investigated under wide ranges of the initial Sn concentrations (0%–26%) and annealing conditions (300–1000 °C, 1 s–48 h). Epitaxial growth triggered by SiGe mixing is observed after annealing, where the annealing temperatures necessary for epitaxial growth significantly decrease with increasing initial Sn concentration and/or annealing time. As a result, Ge-rich (∼80%) SiGe layers with Sn concentrations of ∼2% are realized by ultra-low temperature annealing (300 °C, 48 h) for a sample with the initial Sn concentration of 26%. The annealing temperature (300 °C) is in the solid-liquid coexisting temperature region of the phase diagram for Ge-Sn system. From detailed analysis of crystallization characteristics and composition profiles in grown layers, it is suggested that SiGe mixing is generated by a liquid-phase reaction even at ultra-low temperatures far below the melting temperature of a-GeSn. This ultra-low-temperature growth technique of Ge-rich SiGe on Si substrates is expected to be useful to realize next-generation LSI, where various multi-functional devices are integrated on Si substrates.

  13. Hexafluoroisopropanol-induced catanionic-surfactants-based coacervate extraction for analysis of lysozyme.

    Xu, Jia; Niu, Manli; Xiao, Yuxiu


    A coacervate extraction method, based on hexafluoroisopropanol (HFIP)-induced catanionic surfactants and coupled with a back-extraction procedure, was developed for separation and purification of proteins, using sodium dodecyl sulfate (SDS) and dodecyltrimethyl ammonium bromide (DTAB) as representative catanionic surfactants and lysozyme as a model protein. After the coacervate extraction and back extraction, the obtained lysozyme solutions were examined in terms of quantitative analysis by capillary electrophoresis, bacteriolytic activity, and circular dichroism (CD). The effects of several parameters including back-extraction solvent, HFIP content, total surfactant concentration, and SDS/DTAB molar ratio were investigated in detail on the extraction efficiency and activity of lysozyme. Under the optimized extraction conditions (66 mM KH2PO4 buffer with pH 6.2 as back-extraction solvent, SDS/DTAB molar ratio = 1:1 mol/mol, total surfactant concentration = 30 mM, HIFP concentration = 8 % v/v), the extraction recovery was 89.8 % (±4.7, n = 3), limit of detection was 2.2 (±0.3, n = 3) μg mL(-1), and meanwhile nearly 65 % of native lysozyme activity was retained. In addition, the activity and CD assays showed that SDS/DTAB molar ratio had a significant influence on the activity and structure of lysozyme after extraction. The DTAB-rich extraction systems, in which the DTAB mole fraction was equal to or larger than 70 %, could keep the activity and structure of lysozyme almost in the native state. Graphical Abstract Procedure of HFIP-induced SDS/DTAB coacervate extraction and back extraction of lysozyme.

  14. Feature Extraction and Analysis of Breast Cancer Specimen

    Bhattacharyya, Debnath; Robles, Rosslin John; Kim, Tai-Hoon; Bandyopadhyay, Samir Kumar

    In this paper, we propose a method to identify abnormal growth of cells in breast tissue and suggest further pathological test, if necessary. We compare normal breast tissue with malignant invasive breast tissue by a series of image processing steps. Normal ductal epithelial cells and ductal / lobular invasive carcinogenic cells also consider for comparison here in this paper. In fact, features of cancerous breast tissue (invasive) are extracted and analyses with normal breast tissue. We also suggest the breast cancer recognition technique through image processing and prevention by controlling p53 gene mutation to some greater extent.

  15. Vacuum Permeator Analysis for Extraction of Tritium from DCLL Blankets

    Humrickhouse, Paul Weston [Idaho National Laboratory; Merrill, Brad Johnson [Idaho National Laboratory


    It is envisioned that tritium will be extracted from DCLL blankets using a vacuum permeator. We derive here an analytical solution for the extraction efficiency of a permeator tube, which is a function of only two dimensionless numbers: one that indicates whether radial transport is limited in the PbLi or in the solid membrane, and another that is the ratio of axial and radial transport times in the PbLi. The permeator efficiency is maximized by decreasing the velocity and tube diameter, and increasing the tube length. This is true regardless of the mass transport correlation used; we review several here and find that they differ little, and the choice of correlation is not a source of significant uncertainty here. The PbLi solubility, on the other hand, is a large source of uncertainty, and we identify upper and lower bounds from the literature data. Under the most optimistic assumptions, we find that a ferritic steel permeator operating at 550 °C will need to be at least an order of magnitude larger in volume than previous conceptual designs using niobium and operating at higher temperatures.

  16. Extraction, Purification, and NMR Analysis of Terpenes from Brown Algae.

    Gaysinski, Marc; Ortalo-Magné, Annick; Thomas, Olivier P; Culioli, Gérald


    Algal terpenes constitute a wide and well-documented group of marine natural products with structures differing from their terrestrial plant biosynthetic analogues. Amongst macroalgae, brown seaweeds are considered as one of the richest source of biologically and ecologically relevant terpenoids. These metabolites, mostly encountered in algae of the class Phaeophyceae, are mainly diterpenes and meroditerpenes (metabolites of mixed biogenesis characterized by a toluquinol or a toluquinone nucleus linked to a diterpene moiety).In this chapter, we describe analytical processes commonly employed for the isolation and structural characterization of the main terpenoid constituents obtained from organic extracts of brown algae. The successive steps include (1) extraction of lipidic content from algal samples; (2) purification of terpenes by column chromatography and semi-preparative high-performance liquid chromatography; and (3) structure elucidation of the isolated terpenes by means of 1D and 2D nuclear magnetic resonance (NMR). More precisely, we propose a representative methodology which allows the isolation and structural determination of the monocyclic meroditerpene methoxybifurcarenone (MBFC) from the Mediterranean brown alga Cystoseira amentacea var. stricta. This methodology has a large field of applications and can then be extended to terpenes isolated from other species of the family Sargassaceae.

  17. Lipids and Fatty Acids in Algae: Extraction, Fractionation into Lipid Classes, and Analysis by Gas Chromatography Coupled with Flame Ionization Detector (GC-FID).

    Guihéneuf, Freddy; Schmid, Matthias; Stengel, Dagmar B


    Despite the number of biochemical studies exploring algal lipids and fatty acid biosynthesis pathways and profiles, analytical methods used by phycologists for this purpose are often diverse and incompletely described. Potential confusion and potential variability of the results between studies can therefore occur due to change of protocols for lipid extraction and fractionation, as well as fatty acid methyl esters (FAME) preparation before gas chromatography (GC) analyses. Here, we describe a step-by-step procedure for the profiling of neutral and polar lipids using techniques such as solid-liquid extraction (SLE), thin-layer chromatography (TLC), and gas chromatography coupled with flame ionization detector (GC-FID). As an example, in this protocol chapter, analyses of neutral and polar lipids from the marine microalga Pavlova lutheri (an EPA/DHA-rich haptophyte) will be outlined to describe the distribution of fatty acid residues within its major lipid classes. This method has been proven to be a reliable technique to assess changes in lipid and fatty acid profiles in several other microalgal species and seaweeds.

  18. Optimization of an effective extraction procedure for the analysis of microcystins in soils and lake sediments

    Chen Wei [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072 (China); Graduate School of Chinese Academy of Sciences, Beijing 100049 (China); Li Lin [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072 (China); Gan Nanqin [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072 (China); Song Lirong [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072 (China)]. E-mail:


    Microcystin analysis in sediments and soils is considered very difficult due to low recovery for extraction. This is the primary limiting factor for understanding the fate of toxins in the interface between water and sediment in both the aquatic ecosystem as well as in soils. In the present study, a wide range of extraction solvents were evaluated over a wide range of pH, extraction approaches and equilibration time to optimize an effective extraction procedure for the analysis of microcystins in soils and lake sediments. The number of extractions required and acids in extraction solutions were also studied. In this procedure, EDTA-sodium pyrophosphate solution was selected as an extraction solvent based on the adsorption mechanism study. The optimized procedure proved to be highly efficient and achieved over 90% recovery. Finally, the developed procedure was applied to field soil and sediment sample collected from Chinese lakes during bloom seasons and microcystins were determined in six of ten samples. - Efficiency of extraction of microcystins from soil and sediment was greatly increased.

  19. Antioxidant, DNA protective efficacy and HPLC analysis of Annona muricata (soursop) extracts.

    George, V Cijo; Kumar, D R Naveen; Suresh, P K; Kumar, R Ashok


    Annona muricata is a naturally occurring edible plant with wide array of therapeutic potentials. In India, it has a long history of traditional use in treating various ailments. The present investigation was carried out to characterize the phytochemicals present in the methanolic and aqueous leaf extracts of A. muricata, followed by validation of its radical scavenging and DNA protection activities. The extracts were also analyzed for its total phenolic contents and subjected to HPLC analysis to determine its active metabolites. The radical scavenging activities were premeditated by various complementary assays (DRSA, FRAP and HRSA). Further, its DNA protection efficacy against H2O2 induced toxicity was evaluated using pBR322 plasmid DNA. The results revealed that the extracts were highly rich in various phytochemicals including luteolin, homoorientin, tangeretin, quercetin, daidzein, epicatechin gallate, emodin and coumaric acid. Both the extracts showed significant (p < 0.05) radical scavenging activities, while methanolic extract demonstrated improved protection against H2O2-induced DNA damage when compared to aqueous extract. A strong positive correlation was observed for the estimated total phenolic contents and radical scavenging potentials of the extracts. Further HPLC analysis of the phyto-constituents of the extracts provides a sound scientific basis for compound isolation.

  20. Preliminary phytochemical screening, Antibacterial potential and GC-MS analysis of two medicinal plant extracts.

    Vijayaram, Seerangaraj; Kannan, Suruli; Saravanan, Konda Mani; Vasantharaj, Seerangaraj; Sathiyavimal, Selvam; P, Palanisamy Senthilkumar


    The presence study was aimed to catalyze the primary metabolites and their confirmation by using GC-MS analysis and antibacterial potential of leaf extract of two important medicinal plant viz., Eucalyptus and Azadirachta indica. The antibacterial potential of the methanol leaf extract of the studied species was tested against Escherichia coli, Pseudomonas aeruginosa, Klebsiellap neumoniae, Streptococcus pyogens, Staphylococcus aureus using by agar well diffusion method. The higher zone of inhibition (16mm) was observed against the bacterium Pseudomonas aeruginosa at 100μl concentration of methanol leaf extract. Preliminary phytochemical analysis of studied species shows that presence of phytochemical compounds like steroids, phenolic compounds and flavonoids. GC-MS analysis confirms the occurrence of 20 different compounds in the methanol leaf extract of the both studied species.