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Sample records for ft waxes composition

  1. Process for producing a petroleum wax composition

    SciTech Connect

    Jones, R.L.

    1991-04-23

    This patent describes a process for producing a wax composition. It comprises: vacuum distilling a petroleum feed to prepare a 650 distillate heavy intermediate petroleum wax, having a melting point range of from about 155{degrees}F. to about 185{degrees}F., subjecting the heavy intermediate petroleum wax to furfural/duosol solvent extraction, dissolving and crystallizing the heavy intermediate petroleum wax from a methyl ethyl ketone/toluene mixed solvent, dissolving and recrystallizing the heavy intermediate petroleum wax from a methyl ethyl ketone/toluene mixed solvent, percolating the recrystallized heavy intermediate petroleum wax in the molten state through a clay bed; and blending the recrystallized heavy intermediate petroleum wax from about 50 weight percent to about 90 weight percent with from about 10 weight percent to about 30 weight percent of a polymeric compound selected from the group consisting of ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, polypropylene and mixtures there of and having a molecular weight of from about 2,000 to about 100,000 and a melt index of from about 1 to about 250{degrees} at 375{degrees}F.

  2. Component composition of deresined brown coal wax

    SciTech Connect

    L.P. Noskova

    2008-10-15

    The products of the alkaline hydrolysis of wax isolated from brown coal from the Sergeevskoe deposit were studied using chromatography and IR and NMR spectroscopy. It was found that hydrocarbons, alcohols, acids, and a representative fraction of unsaponifiable esters were the constituents of wax. High-molecular-weight fatty alcohols and acids were identified as the constituents of wax with the use of thin-layer chromatography.

  3. WAXS investigations on Polyethylene -- Carbon Nanofibers Composites

    NASA Astrophysics Data System (ADS)

    Jones, Brian; Li, Jianhua; Benitez, Rogelio; Lozano, Karen; Chipara, Mircea; Cristian Chipara, Alin; Dorina Chipara, Magdalena; Sellmyer, David J.

    2008-03-01

    Nanocomposites have been obtained by high-shear mixing of isotactic polyethylene with various amounts of purified nanofiller (vapor grown carbon nanofibers type PR-24AG from Pyrograf Products, Inc) by utilizing a HAAKE Rheomix at 65 rpm and 180 ^oC for 9 min followed by an additional mixing at 90 rpm for 5 min. Composites loaded with various amounts of vapor grown carbon nanofibers have been prepared. Various spectroscopic techniques have been used to assess the interactions between the polymeric matrix and carbon nanofibers. Wide angle X - Ray scattering investigations focused on the effect of carbon nanofibers on the crystalline phases of polypropylene and on the overall crystallinity degree of the polymeric matrix. This research aims at a better understanding of the nature and structure of the polymer -- carbon nanofibers interface.

  4. Chemical Composition of the Epicuticular and Intracuticular Wax Layers on Adaxial Sides of Rosa canina Leaves

    PubMed Central

    Buschhaus, Christopher; Herz, Hubert; Jetter, Reinhard

    2007-01-01

    Background and Aims The waxy cuticle is the first point of contact for many herbivorous and pathogenic organisms on rose plants. Previous studies have reported the average composition of the combined wax extract from both sides of rose leaves. Recently, the compositions of the waxes on the adaxial and abaxial surfaces of Rosa canina leaves were determined separately. In this paper, a first report is made on the compositions of the epicuticular and intracuticular wax layers of Rosa canina leaves. The methods described enable the determination of which compounds are truly available at the surface for plant–organism interactions. METHOD An adhesive was used to mechanically strip the epicuticular wax from the adaxial leaf surface and the removal was visually confirmed using scanning electron microscopy. After the epicuticular wax had been removed, the intracuticular wax was then isolated using standard chemical extraction. Gas chromatography, flame ionization detection and mass spectrometry were used to identify and quantify compounds in the separated wax mixtures. Key Results The epicuticular wax contained higher concentrations of alkanes and alkyl esters but lower concentrations of primary alcohols and alkenols when compared to the intracuticular wax. In addition, the average chain lengths of these compound classes were higher in the epicuticular wax. Secondary alcohols were found only in the epicuticular layer while triterpenoids were restricted mainly to the intracuticular wax. Conclusions A gradient exists between the composition of the epi- and intracuticular wax layers of Rosa canina leaves. This gradient may result from polarity differences, in part caused by differences in chain lengths. The outer wax layer accessible to the phyllosphere showed a unique composition of wax compounds. The ecological consequences from such a gradient may now be probed. PMID:17933845

  5. Low severity upgrading of F-T waxes with solid superacids. Final report

    SciTech Connect

    Wender, I.; Tierney, J.W.

    1995-09-30

    The use of solid acids, especially Pt/ZrO{sub 2}/SO{sub 4}, to convert long chain alkanes and Fischer-Tropsch waxes to liquid fuels under mild reaction conditions was explored in this work. Anion and/or hydrogenation metal modified zirconium oxides were synthesized, characterized, and tested for hydrocracking and hydroisomerization. of model compounds, chiefly with n-hexadecane. The relationship between catalytic activity and acidic character of the bifunctional Pt/ZrO{sub 2}/SO{sub 4} catalyst was investigated.

  6. Phase Change Insulation for Energy Efficiency Based on Wax-Halloysite Composites

    NASA Astrophysics Data System (ADS)

    Zhao, Yafei; Thapa, Suvhashis; Weiss, Leland; Lvov, Yuri

    2014-08-01

    Phase change materials (PCMs) have gained extensive attention in thermal energy storage. Wax can be used as a PCM in solar storage but it has low thermal conductivity. Introducing 10% halloysite admixed into wax yields a novel composite (wax-halloysite) which has a thermal conductivity of 0.5 W/mK. To increase the base conductivity, graphite and carbon nanotubes were added into the PCM composite improving its thermal energy storage. Thermal conductivity of wax-halloysite-graphite (45/45/10%) composite showed increased conductivity of 1.4 W/mK (3 times higher than the base wax-halloysite composite). Wax- halloysite-graphite-carbon nanotubes (45/45/5/5%) composite showed conductivity of 0.85 W/mK while maintaining the original shape perfectly until 91 °C (above the original wax melting point). Thermal conductivity can be further increased with higher doping of carbon nanotubes. This new composites are promising heat storage material due to good thermal stability, high thermal/electricity conductivity and ability to preserve its shape during phase transitions.

  7. Low severity upgrading of F-T waxes with solid superacids

    SciTech Connect

    Wender, I.; Tierney, J.W.

    1992-07-20

    We have previously reported the isomerization and hydrocracking of n-hexadecane and a n-C{sub 32} straight chain paraffin with a Pt/ZrO{sub 2}/SO{sub 4} catalyst at 170{degrees}C and 350 psig of hydrogen. This study has now been extended to the treatment of a Fisher-Tropsch wax with a carbon number range from C{sub 55}-C{sub 62}. The results reported in Table 1 show that the Pt/ZrO{sub 2}/SO{sub 4} catalyst is active for the isomerization and hydrocracking of this substrate. At an 88.6 wt% conversion level, an 86.1% selectivity to isoparaffins was achieved. The products consisted mainly of C{sub 4}-C{sub 9} and C{sub 10}-C{sub 14} fractions, suitable as gasoline and diesel fuels. A feed/catalyst ratio of 6:1 was used; there was no evidence of catalytic deactivation. The melted wax is viscous and there was a decrease in conversion with time, indicating that diffusion might be a limitation for chains of very high molecular weight.

  8. Thermal conductivity of the diamond-paraffin wax composite

    NASA Astrophysics Data System (ADS)

    Abyzov, A. M.; Kidalov, S. V.; Shakhov, F. M.

    2011-01-01

    The thermal conductivity of diamond-paraffin wax composites prepared by infiltration of a hydrocarbon binder with the thermal conductivity λ m = 0.2 W m-1 K-1 into a dense bed of diamond particles (λ f ˜ 1500 W m-1 K-1) with sizes of 400 and 180 μm has been investigated. The calculations using universally accepted models considering isolated inclusions in a matrix have demonstrated that the best agreement with the measured values of the thermal conductivity of the composite λ = 10-12 W m-1 K-1 is achieved with the use of the differential effective medium model, the Maxwell mean field scheme gives a very underestimated calculated value of λ, and the effective medium theory leads to a very overestimated value. An agreement between the calculation and the experiment can be provided by constructing thermal conductivity functions. The calculation of the thermal conductivity at the percolation threshold has shown that the experimental thermal conductivity of the composites is higher than this critical value. It has been established that, for the composites with closely packed diamond particles (the volume fraction is ˜0.63 for a monodisperse binder), the use of the isolated particle model (Hasselman-Johnson and differential effective medium models) for calculating the thermal conductivity is not quite correct, because the model does not take into account the percolation component of the thermal conductivity. In particular, this holds true for the calculation of the heat conductance of diamond-matrix interfaces in diamond-metal composites with a high thermal conductivity.

  9. What do microbes encounter at the plant surface? Chemical composition of pea leaf cuticular waxes.

    PubMed

    Gniwotta, Franka; Vogg, Gerd; Gartmann, Vanessa; Carver, Tim L W; Riederer, Markus; Jetter, Reinhard

    2005-09-01

    In the cuticular wax mixtures from leaves of pea (Pisum sativum) cv Avanta, cv Lincoln, and cv Maiperle, more than 70 individual compounds were identified. The adaxial wax was characterized by very high amounts of primary alcohols (71%), while the abaxial wax consisted mainly of alkanes (73%). An aqueous adhesive of gum arabic was employed to selectively sample the epicuticular wax layer on pea leaves and hence to analyze the composition of epicuticular crystals exposed at the outermost surface of leaves. The epicuticular layer was found to contain 74% and 83% of the total wax on adaxial and abaxial surfaces, respectively. The platelet-shaped crystals on the adaxial leaf surface consisted of a mixture dominated by hexacosanol, accompanied by substantial amounts of octacosanol and hentriacontane. In contrast, the ribbon-shaped wax crystals on the abaxial surface consisted mainly of hentriacontane (63%), with approximately 5% each of hexacosanol and octacosanol being present. Based on this detailed chemical analysis of the wax exposed at the leaf surface, their importance for early events in the interaction with host-specific pathogenic fungi can now be evaluated. On adaxial surfaces, approximately 80% of Erysiphe pisi spores germinated and 70% differentiated appressoria. In contrast, significantly lower germination efficiencies (57%) and appressoria formation rates (49%) were found for abaxial surfaces. In conclusion, the influence of the physical structure and the chemical composition of the host surface, and especially of epicuticular leaf waxes, on the prepenetration processes of biotrophic fungi is discussed.

  10. The Influence of Source Biases on Sedimentary Leaf Waxes and Their Stable Isotope Compositions

    NASA Astrophysics Data System (ADS)

    Diefendorf, A. F.; Freimuth, E. J.; Lowell, T. V.; Wiles, G. C.

    2015-12-01

    Leaf waxes and their carbon (δ13C) and hydrogen (δD) isotopic compositions are an important tool to understand past changes in paleoclimate and paleovegetation. Important recent advances in our understanding about the isotopic signal preserved in sedimentary leaf waxes have been inferred from studies made on individual modern plants. However, paleoreconstructions are based on sedimentary leaf waxes, which reflect mixing between multiple sources, such as ablated leaf waxes from nearby or from afar, wind blown leaf litter, and riverine transported leaf waxes. Each of these sources integrates leaf waxes from different species and growth forms, likely resulting in source-specific taphonomic biases on sedimentary leaf wax isotopes. To better understand source biases in sedimentary leaf waxes, we investigated n-alkanes and n-alkanoic acids and their carbon and hydrogen isotopes in vegetation and lake sediments at Brown's Lake and Bog, a 'simple' forested closed-basin lake in northeastern Ohio. Interestingly, we found that tree n-alkane δD varied substantially during the growing season, broadly tracking changes in source water composition. However, δD values of n-alkanes in the tree leaf litter did not match that of the most recent sedimentary n-alkanes. Instead, surface sediment n-alkane δD more closely matched that of the woody shrubs and grasses growing right around the lake. n-Alkanoic acid data is forthcoming. We are currently exploring lake sediment n-alkane accumulation rates against midwestern flux rates of wind blown leaf waxes from afar. Our preliminary results suggest that although studies made on individual leaves are indeed important, we may need to consider additional leaf wax sources that potentially influence sedimentary archives.

  11. Bioinspired Composite Coating with Extreme Underwater Superoleophobicity and Good Stability for Wax Prevention in the Petroleum Industry.

    PubMed

    Liang, Weitao; Zhu, Liqun; Li, Weiping; Yang, Xin; Xu, Chang; Liu, Huicong

    2015-10-13

    Wax deposition is a detrimental problem that happens during crude oil production and transportation, which greatly reduces transport efficiency and causes huge economic losses. To avoid wax deposition, a bioinspired composite coating with excellent wax prevention and anticorrosion properties is developed in this study. The prepared coating is composed of three films, including an electrodeposited Zn film for improving corrosion resistance, a phosphating film for constructing fish-scale morphology, and a silicon dioxide film modified by a simple spin-coating method for endowing the surface with superhydrophilicity. Good wax prevention performance has been investigated in a wax deposition test. The surface morphology, composition, wetting behaviors, and stability are systematically studied, and a wax prevention mechanism is proposed, which can be calculated from water film theory. This composite coating strategy which shows excellent properties in both wax prevention and stability is expected to be widely applied in the petroleum industry. PMID:26375275

  12. Bioinspired Composite Coating with Extreme Underwater Superoleophobicity and Good Stability for Wax Prevention in the Petroleum Industry.

    PubMed

    Liang, Weitao; Zhu, Liqun; Li, Weiping; Yang, Xin; Xu, Chang; Liu, Huicong

    2015-10-13

    Wax deposition is a detrimental problem that happens during crude oil production and transportation, which greatly reduces transport efficiency and causes huge economic losses. To avoid wax deposition, a bioinspired composite coating with excellent wax prevention and anticorrosion properties is developed in this study. The prepared coating is composed of three films, including an electrodeposited Zn film for improving corrosion resistance, a phosphating film for constructing fish-scale morphology, and a silicon dioxide film modified by a simple spin-coating method for endowing the surface with superhydrophilicity. Good wax prevention performance has been investigated in a wax deposition test. The surface morphology, composition, wetting behaviors, and stability are systematically studied, and a wax prevention mechanism is proposed, which can be calculated from water film theory. This composite coating strategy which shows excellent properties in both wax prevention and stability is expected to be widely applied in the petroleum industry.

  13. Alignment of graphene sheets in wax composites for electromagnetic interference shielding improvement

    NASA Astrophysics Data System (ADS)

    Song, Wei-Li; Cao, Mao-Sheng; Lu, Ming-Ming; Yang, Jian; Ju, Hong-Fei; Hou, Zhi-Ling; Liu, Jia; Yuan, Jie; Fan, Li-Zhen

    2013-03-01

    Rapid advancements in carbon-based fillers have enabled a new and more promising platform in the development of electromagnetic attenuation composites. Alignment of fillers in composites with specific structures and morphologies has been widely pursued to achieve high performance based on taking advantage of unique filler characteristics. In this work, few-layer graphene (FLG), obtained from direct exfoliation of graphite, was fabricated into paraffin wax to prepare FLG/wax composites and investigate their electromagnetic interference (EMI) shielding performance. The as-exfoliated FLG/wax samples have shown much improved EMI performance compared to the commercial graphite/wax ones. For further improvement of EMI shielding performance, split-press-merge approaches were applied to align the FLG fillers to achieve anisotropic characteristics in the plane perpendicular to the pressing direction. Much enhanced EMI shielding performance coupled with an improvement in absorption and reflection was observed in the post-alignment FLG/wax composites. An average interparticle distance model associated with improved electrically conducting interconnection and enlarged effective reflection regions with respect to enhanced reflection efficiency were discussed. The results suggest a platform and promising opportunities for preparing high-performance EMI shielding composites.

  14. Alignment of graphene sheets in wax composites for electromagnetic interference shielding improvement.

    PubMed

    Song, Wei-Li; Cao, Mao-Sheng; Lu, Ming-Ming; Yang, Jian; Ju, Hong-Fei; Hou, Zhi-Ling; Liu, Jia; Yuan, Jie; Fan, Li-Zhen

    2013-03-22

    Rapid advancements in carbon-based fillers have enabled a new and more promising platform in the development of electromagnetic attenuation composites. Alignment of fillers in composites with specific structures and morphologies has been widely pursued to achieve high performance based on taking advantage of unique filler characteristics. In this work, few-layer graphene (FLG), obtained from direct exfoliation of graphite, was fabricated into paraffin wax to prepare FLG/wax composites and investigate their electromagnetic interference (EMI) shielding performance. The as-exfoliated FLG/wax samples have shown much improved EMI performance compared to the commercial graphite/wax ones. For further improvement of EMI shielding performance, split-press-merge approaches were applied to align the FLG fillers to achieve anisotropic characteristics in the plane perpendicular to the pressing direction. Much enhanced EMI shielding performance coupled with an improvement in absorption and reflection was observed in the post-alignment FLG/wax composites. An average interparticle distance model associated with improved electrically conducting interconnection and enlarged effective reflection regions with respect to enhanced reflection efficiency were discussed. The results suggest a platform and promising opportunities for preparing high-performance EMI shielding composites.

  15. Pressure and composition effect on wax precipitation: Experimental data and model results

    SciTech Connect

    Pan, H.; Firoozabadi, A.; Fotland, P.

    1996-12-31

    Wax precipitation is often studied using the stock tank oil. However, precipitation may be very different in well tubing and production facilities due to the effects of pressure and composition. As an example, the cloudpoint temperature may decrease as much as 15 K from atmospheric pressure to the saturation pressure of 100 bar mostly due to the dissolution of light gases into the oil (i.e. due to composition changes). It is also often assumed that the addition of solvents such as C{sub 5} and C{sub 6} decreases the cloudpoint temperature. On the contrary, from our modeling results, we have found that the mixing of a crude with a solvent increases the cloudpoint temperature (i.e., enhances the wax precipitation). In this study, the cloudpoint temperature at live oil conditions and the amount of the precipitated wax at stock tank oil conditions are provided for three crudes. A modified multisolid wax precipitation model is used to study the effects of pressure and composition on wax precipitation. The modeling results reveal that an increase in methane and CO{sub 2} concentration decreases the cloudpoint temperature while an increase in C{sub 5} concentration increases the cloud point temperature.

  16. Amperometric determination of hydrazine at manganese hexacyanoferrate modified graphite-wax composite electrode.

    PubMed

    Jayasri, D; Narayanan, S Sriman

    2007-06-01

    Fabrication, characterization and application of a manganese hexacyanoferrate (MnHCF) modified graphite-wax composite electrode are described. The MnHCF mixed with graphite powder was dispersed into molten paraffin wax to yield a conductive composite, which was used as electrode material to construct a renewable three-dimensional MnHCF modified electrode. The characterization of the modified electrode has been studied by electrochemical techniques. The cyclic voltammogram of the MnHCF modified graphite-wax composite electrode prepared under optimum composition, showed a well-defined redox couple due to Fe(CN)(6)(4-)/Fe(CN)(6)(3-) system. The electrocatalytic oxidation of hydrazine by MnHCF modified graphite-wax composite electrode has been investigated in an attempt to develop a new sensor for its determination. It was found that the mediator catalyzed the oxidation of hydrazine. The electrocatalytic oxidation of hydrazine was also studied under hydrodynamic and chronoamperometric conditions. The anodic current increases linearly with increase in the concentration of hydrazine in the range of 3.33x10(-5)M to 8.18x10(-3)M. The detection limit was found to be 6.65x10(-6)M (S/N=3). The modified electrode can also be used for on-line detection of hydrazine. The proposed method has also been applied for the determination of hydrazine in photographic developer solution.

  17. Composition of epicuticular wax on Prosopis glandulosa leaves

    SciTech Connect

    Mayeux, H.S. Jr.; Wilkinson, R.E. Univ. of Georgia Agricultural Experiment Station, Experiment )

    1990-06-01

    Epicuticular wax on leaves of field-grown honey mesquite (Prosopis glandulosa Torr.) trees consisted of 35% esters, 32% alkanes, 25% free fatty alcohols, and 7% free fatty acids. Aldehydes were present in very low concentrations. The number of carbon atoms (C{sub n}) of alkanes ranged from 25 to 31, with a maximum (57%) at 29. Esters consisted of fatty acids with C{sub n} of 16, 18, and 20, with most (70%) at 18 and fatty alcohols with C{sub n} of 24-32. The C{sub n} of free fatty alcohols and free fatty acids also ranged from 24 to 32. Only primary alcohols were present. Immediately after exposure of glasshouse-grown seedlings to {sup 14}CO{sub 2} for 4 h, 60% of the recovered {sup 14}C was incorporated into free fatty acids; the percentage decreased progressively to 18% 8 h after exposure and remained stable thereafter. The proportion of {sup 14}C in free fatty alcohols increased from ca. 12% immediately after exposure to {sup 14}CO{sub 2} to 55% at 8 h. Little {sup 14}C was associated with other wax components over the 24-h period; 3% or less was incorporated into alkanes.

  18. Low severity upgrading of F-T waxes with solid superacids. Quarterly report, September 1, 1993--November 30, 1993

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1994-01-31

    During the last quarter we characterized the acidity of platinum-promoted solid superacids by TPD (temperature-programmed desorption) and investigated the effect of sulfate concentration on the activity of Pt/ZrO{sub 2}/SO{sub 4} catalysts for isomerization and hydrocracking of n-hexadecane. The activities of Pt/ZrO{sub 2} promoted by different anions (SO{sub 4}{sup 2 {minus}}, MoO{sub 4}{sup 2{minus}} and WO{sub 4}{sup 2{minus}}), to give Pt/ZrO{sub 2}/SO{sub 4}, Pt/ZrO{sub 2}/MoO{sub 4} and Pt/ZrO{sub 2}/WO{sub 4}, were compared and the results related to their acidity and acid strength determined by TPD. TPD was an effective tool for the rapid evaluation of the acidity of metal-promoted solid superacids; this technique provided a good indication of the activity of the bifunctional solid superacids. The activity of the Pt/ZrO{sub 2}/SO{sub 4} catalyst at 160{degrees}C was compared with a Pt/{gamma}-Al{sub 2}O{sub 3} reforming catalyst at 160{degrees}C and also at 400{degrees}C (350 psig H{sub 2}), respectively. The Pt/{gamma}-Al{sub 2}O{sub 3} catalyst was not effective at 160{degrees}C but gave a 6.2 wt% conversion of the n-hexadecane to isomerized and cracked products at 400{degrees}C. The isomerization and hydrocracking of long-chain paraffins over metal-promoted solid superacids were carried out in the presence of selected aromatic compounds. It appears that the presence of aromatics changes the surface acidity of the catalyst, resulting in higher molecular weight products (from C{sub 4}{minus}C{sub 9} to C{sub 10}{minus}C{sub 16}) from n-hexadecane. This finding is important in obtaining a more desirable product distribution from hydrocracking of F-T waxes.

  19. Composition of the wax fraction of bitumen from methylated brown coals

    SciTech Connect

    S.I. Zherebtsov; A.I. Moiseev

    2009-04-15

    Changes in the group and individual compositions of the wax fractions of bitumen in the course of brown coal methylation were studied. With the use of IR and NMR spectroscopy and chromatography-mass spectrometry, it was found that the esters of methylated coal waxes consisted of the native esters of fatty acids and the methyl esters of these acids formed as a result of an alkylation treatment. Esterification and transesterification were predominant among the reactions of aliphatic fraction components. A positive effect of methanol alkylation on an increase in the yield of the aliphatic fractions was found.

  20. Electro- and photodriven phase change composites based on wax-infiltrated carbon nanotube sponges.

    PubMed

    Chen, Liangjie; Zou, Ruqiang; Xia, Wei; Liu, Zhenpu; Shang, Yuanyuan; Zhu, Jinlong; Wang, Yingxia; Lin, Jianhua; Xia, Dingguo; Cao, Anyuan

    2012-12-21

    Organic phase change materials are usually insulating in nature, and they are unlikely to directly trigger latent heat storage through an electrical way. Here we report a multifunctional phase change composite in which the energy storage can be driven by small voltages (e.g., 1.5 V) or light illumination with high electro-to-heat or photo-to-thermal storage efficiencies (40% to 60%). The composite is composed of paraffin wax infiltrated into a porous, deformable carbon nanotube sponge; the latter not only acts as a flexible encapsulation scaffold for wax but also maintains a highly conductive network during the phase change process (for both solid and liquid states). Uniform interpenetration between the nanotube network and paraffin wax with high affinity results in enhanced phase change enthalpy and thermal conductivity compared to pure paraffin wax. Our phase change composite can store energy in practical ways such as by sunlight absorption or under voltages applied by conventional lithium-ion batteries.

  1. Grapefruit gland oil composition is affected by wax application, storage temperature, and storage time.

    PubMed

    Sun, D; Petracek, P D

    1999-05-01

    The effect of wax application, storage temperature (4 or 21 degrees C), and storage time (14 or 28 days after wax application) on grapefruit gland oil composition was examined by capillary gas chromatography. Wax application decreases nonanal and nootkatone levels. beta-Pinene, alpha-phellandrene, 3-carene, ocimene, octanol, trans-linalool oxide, and cis-p-mentha-2,8-dien-1-ol levels increase, but limonene levels decrease, with temperature. Levels of alpha-pinene, limonene, linalool, citronellal, alpha-terpineol, neral, dodecanal, and alpha-humulene decrease with time. Levels of alpha-phellandrene, 3-carene, ocimene, and trans-linalool oxide increase with time. No compound level was affected by the interactive action of temperature and wax application, suggesting that these two factors cause grapefruit oil gland collapse (postharvest pitting) through means other than changing gland oil composition. Compounds that are toxic to the Caribbean fruit fly (alpha-pinene, limonene, alpha-terpineol, and some aldehydes) decrease with time, thus suggesting grapefruit becomes increasingly susceptible to the fly during storage. PMID:10552497

  2. Variations of the composition of the leaf cuticular wax among Chinese populations of Plantago major.

    PubMed

    Guo, Yanjun; He, Yuji; Guo, Na; Gao, Jianhua; Ni, Yu

    2015-04-01

    Plantago major L. grows in a very wide range of regions in China and exhibits great variations among populations. The analysis of the cuticular-wax composition provides a potential approach to classify populations of P. major confronting different environmental conditions. Twelve populations of P. major and five populations of P. depressa Willd., distributed over regions with average annual temperatures ranging from -2.0 to 18.4°, were sampled, the variation of the composition of their cuticular waxes was analyzed, and their values of average chain length (ACL) and carbon preference index (CPI) were calculated. Great intra- and interspecies variations were observed for the total wax contents. The average annual temperature of the habitats was significantly correlated with the relative contents of the dominant n-alkanes with an odd number of C-atoms, but not with the wax contents. With an increasing average annual temperature, the relative contents of n-alkanes C29 and C31 decreased, whereas those of C33 and C35 as well as the values of ACLtotal and ACL27-33 increased. Cluster analysis based on the pattern of the n-alkane distribution allowed to clearly separate the populations of P. major according to the average annual temperature of their habitats, but not to separate the populations of the two species. Hence, the pattern of the n-alkane distribution might be a good taxonomic marker for P. major at the intraspecies level, but not at the interspecies level. Nevertheless, a small difference between the populations of the two species was observed concerning the values of ACLtotal and CPItotal , implying the potential use of these indices for the classification of the populations of the two species at the interspecies level. PMID:25879506

  3. Variations of the composition of the leaf cuticular wax among Chinese populations of Plantago major.

    PubMed

    Guo, Yanjun; He, Yuji; Guo, Na; Gao, Jianhua; Ni, Yu

    2015-04-01

    Plantago major L. grows in a very wide range of regions in China and exhibits great variations among populations. The analysis of the cuticular-wax composition provides a potential approach to classify populations of P. major confronting different environmental conditions. Twelve populations of P. major and five populations of P. depressa Willd., distributed over regions with average annual temperatures ranging from -2.0 to 18.4°, were sampled, the variation of the composition of their cuticular waxes was analyzed, and their values of average chain length (ACL) and carbon preference index (CPI) were calculated. Great intra- and interspecies variations were observed for the total wax contents. The average annual temperature of the habitats was significantly correlated with the relative contents of the dominant n-alkanes with an odd number of C-atoms, but not with the wax contents. With an increasing average annual temperature, the relative contents of n-alkanes C29 and C31 decreased, whereas those of C33 and C35 as well as the values of ACLtotal and ACL27-33 increased. Cluster analysis based on the pattern of the n-alkane distribution allowed to clearly separate the populations of P. major according to the average annual temperature of their habitats, but not to separate the populations of the two species. Hence, the pattern of the n-alkane distribution might be a good taxonomic marker for P. major at the intraspecies level, but not at the interspecies level. Nevertheless, a small difference between the populations of the two species was observed concerning the values of ACLtotal and CPItotal , implying the potential use of these indices for the classification of the populations of the two species at the interspecies level.

  4. Low severity upgrading of F-T waxes with solid superacids. Progress report, March 1, 1992--May 30, 1992

    SciTech Connect

    Wender, I.; Tierney, J.W.

    1992-07-20

    We have previously reported the isomerization and hydrocracking of n-hexadecane and a n-C{sub 32} straight chain paraffin with a Pt/ZrO{sub 2}/SO{sub 4} catalyst at 170{degrees}C and 350 psig of hydrogen. This study has now been extended to the treatment of a Fisher-Tropsch wax with a carbon number range from C{sub 55}-C{sub 62}. The results reported in Table 1 show that the Pt/ZrO{sub 2}/SO{sub 4} catalyst is active for the isomerization and hydrocracking of this substrate. At an 88.6 wt% conversion level, an 86.1% selectivity to isoparaffins was achieved. The products consisted mainly of C{sub 4}-C{sub 9} and C{sub 10}-C{sub 14} fractions, suitable as gasoline and diesel fuels. A feed/catalyst ratio of 6:1 was used; there was no evidence of catalytic deactivation. The melted wax is viscous and there was a decrease in conversion with time, indicating that diffusion might be a limitation for chains of very high molecular weight.

  5. Physical Properties, Volatiles Compositions and Sensory Descriptions of the Aromatized Hazelnut Oil-Wax Organogels.

    PubMed

    Yılmaz, Emin; Öğütcü, Mustafa; Yüceer, Yonca Karagül

    2015-09-01

    The purpose of this study was to determine the physicochemical, thermal and sensorial features of vitamin enriched and aromatized hazelnut oil-beeswax and sunflower wax organogels. Another objective was to monitor the influence of storage on textural and oxidative stability and volatile composition of the organogels. The results show that organogels with beeswax had lower levels of solid fat content, melting point and firmness than sunflower wax counterparts. The microphotographs revealed that beeswax organogels had spherical crystals while sunflower wax organogels continued need-like crystals, but both organogels continued crystallized β' polymorph. All organogels maintained their oxidative stability during storage. Quantitative descriptive analysis results were consistent with these findings that the organogel structure and properties were similar to breakfast margarine. The main volatile components of the organogels with added strawberry aroma were ethyl acetate, ethyl butanoate, ethyl-2-methyl butanoate, D-limonene, ethyl caproate; banana-aroma were isoamyl acetate, isoamyl valerianate, ethyl acetate; and butter-aroma were 2,3-butanedione, 3-hydroxy-2-butanone. These volatile components were not only detected in the fresh samples but also at the end of the storage period. Sensory definition terms were matched with the sensory descriptors of the detected volatiles. In conclusion, the new organogels were shown to be suitable for food product applications. PMID:26259923

  6. Physical Properties, Volatiles Compositions and Sensory Descriptions of the Aromatized Hazelnut Oil-Wax Organogels.

    PubMed

    Yılmaz, Emin; Öğütcü, Mustafa; Yüceer, Yonca Karagül

    2015-09-01

    The purpose of this study was to determine the physicochemical, thermal and sensorial features of vitamin enriched and aromatized hazelnut oil-beeswax and sunflower wax organogels. Another objective was to monitor the influence of storage on textural and oxidative stability and volatile composition of the organogels. The results show that organogels with beeswax had lower levels of solid fat content, melting point and firmness than sunflower wax counterparts. The microphotographs revealed that beeswax organogels had spherical crystals while sunflower wax organogels continued need-like crystals, but both organogels continued crystallized β' polymorph. All organogels maintained their oxidative stability during storage. Quantitative descriptive analysis results were consistent with these findings that the organogel structure and properties were similar to breakfast margarine. The main volatile components of the organogels with added strawberry aroma were ethyl acetate, ethyl butanoate, ethyl-2-methyl butanoate, D-limonene, ethyl caproate; banana-aroma were isoamyl acetate, isoamyl valerianate, ethyl acetate; and butter-aroma were 2,3-butanedione, 3-hydroxy-2-butanone. These volatile components were not only detected in the fresh samples but also at the end of the storage period. Sensory definition terms were matched with the sensory descriptors of the detected volatiles. In conclusion, the new organogels were shown to be suitable for food product applications.

  7. Hydrogen isotope composition of leaf wax n-alkanes in Arabidopsis lines with different transpiration rates

    NASA Astrophysics Data System (ADS)

    Pedentchouk, N.; Lawson, T.; Eley, Y.; McAusland, L.

    2012-04-01

    Stable isotopic compositions of oxygen and hydrogen are used widely to investigate modern and ancient water cycles. The D/H composition of organic compounds derived from terrestrial plants has recently attracted significant attention as a proxy for palaeohydrology. However, the role of various plant physiological and biochemical factors in controlling the D/H signature of leaf wax lipids in extant plants remains unclear. The focus of this study is to investigate the effect of plant transpiration on the D/H composition of n-alkanes in terrestrial plants. This experiment includes 4 varieties of Arabidopsis thaliana that differ with respect to stomatal density and stomatal geometry. All 4 varieties were grown indoors under identical temperature, relative humidity, light and watering regimes and then sampled for leaf wax and leaf water stable isotopic measurements. During growth, stomatal conductance to carbon dioxide and water vapour were also determined. We found that the plants varied significantly in terms of their transpiration rates. Transpiration rates were significantly higher in Arabidopsis ost1 and ost1-1 varieties (2.4 and 3.2 mmol m-2 s-1, respectively) than in Arabidopsis RbohD and Col-0 (1.5 and 1.4). However, hydrogen isotope measurements of n-alkanes extracted from leaf waxes revealed a very different pattern. Varieties ost1, ost1-1, and RbohD have very similar deltaD values of n-C29 alkane (-125, -128, and -127 per mil), whereas the deltaD value of Col-0 is more negative (-137 per mil). The initial results of this work suggest that plant transpiration is decoupled from the D/H composition of n-alkanes. In other words, physical processes that affect water vapour movement between the plant and its environment apparently cannot account for the stable hydrogen isotope composition of organic compounds that comprise leaf waxes. Additional, perhaps biochemical, processes that affect hydrogen isotope fractionation during photosynthesis might need to be invoked

  8. Wax sweating

    SciTech Connect

    Rueff, R.M.

    1991-05-14

    This patent describes a wax sweating process. It comprises: solidifying molten wax; sweating the solidified wax; withdrawing liquid drippings; determining the relationship of the melting point; monitoring the congealing point; determining the melting point; ceasing sweating of the remaining solidified wax; heating the remaining solidified wax; and discharging the melted wax product.

  9. Ultrawide Band Microwave Absorption Properties of Ultrasound Processed CrO2-Paraffin Wax Composites

    NASA Astrophysics Data System (ADS)

    Xi, Li; Yang, Yikai

    2011-03-01

    The microwave absorption properties of ultrasound processed CrO2-paraffin wax composites are investigated in the frequency range of 0.1-18 GHz by the coaxial method. By analysis and comparison between ultrasound processed sample and the unprocessed sample, we discovered that the ultrasound treatment will induce a thin insulating Cr2O3 shell over the CrO2 rods to form a core/shell structure that performs excellent in microwave absorption. An optimum reflection loss of -50.9 dB was found at 5.2 GHz with a matching thickness of 3.4 mm for 70 wt % CrO2-paraffin wax composite. Moreover, the frequency range of which the reflection loss is less than -20 dB spreads from 4.0 to 8.7 GHz with the corresponding absorption thickness ranges from 2.3 to 4.0 mm. The comparison among our result and other reported ones indicates that, in addition to its common applications, the CrO2 after certain process may have potential in microwave absorption. More profoundly, the technique of ultrasound process employed in this report may suggest a new method to induce, according to different needs, crystalline phase transition for a various range of metastable chemicals.

  10. Patchable, flexible heat-sensing hybrid ionic gate nanochannel modified with a wax-composite

    NASA Astrophysics Data System (ADS)

    Chun, Kyoung-Yong; Choi, Wook; Roh, Sung-Cheoul; Han, Chang-Soo

    2015-07-01

    Heat-driven ionic gate nanochannels have been recently demonstrated, which exploit temperature-responsive polymer brushes based on wettability. These heat-sensing artificial nanochannels operate in a broad temperature-response boundary and fixed liquid cell environment, thereby experiencing limited system operation in the flat and solid state. Here we have developed a patchable and flexible heat-sensing artificial ionic gate nanochannel, which can operate in the range of the human body temperature. A wax-elastic copolymer, coated onto a commercial nanopore membrane by a controlled-vacuum filtration method, was used for the construction of temperature-responsive nanopores. The robust and flexible nanochannel heat sensor, which is combined with an agarose gel electrolyte, can sustain reversible thermo-responsive ionic gating based on the volumetric work of the wax-composite layers in a selective temperature range. The ionic current is also effectively distinguished in the patchable bandage-type nanochannel for human heat-sensing.Heat-driven ionic gate nanochannels have been recently demonstrated, which exploit temperature-responsive polymer brushes based on wettability. These heat-sensing artificial nanochannels operate in a broad temperature-response boundary and fixed liquid cell environment, thereby experiencing limited system operation in the flat and solid state. Here we have developed a patchable and flexible heat-sensing artificial ionic gate nanochannel, which can operate in the range of the human body temperature. A wax-elastic copolymer, coated onto a commercial nanopore membrane by a controlled-vacuum filtration method, was used for the construction of temperature-responsive nanopores. The robust and flexible nanochannel heat sensor, which is combined with an agarose gel electrolyte, can sustain reversible thermo-responsive ionic gating based on the volumetric work of the wax-composite layers in a selective temperature range. The ionic current is also

  11. Transient silencing of the KASII genes is feasible in Nicotiana benthamiana for metabolic engineering of wax ester composition

    PubMed Central

    Aslan, Selcuk; Hofvander, Per; Dutta, Paresh; Sitbon, Folke; Sun, Chuanxin

    2015-01-01

    The beta-ketoacyl-ACP synthase II (KASII) is an enzyme in fatty acid biosynthesis, catalyzing the elongation of 16:0-acyl carrier protein (ACP) to 18:0-ACP in plastids. Mutations in KASII genes in higher plants can lead to lethality, which makes it difficult to utilize the gene for lipid metabolic engineering. We demonstrated previously that transient expression of plastid-directed fatty acyl reductases and wax ester synthases could result in different compositions of wax esters. We hypothesized that changing the ratio between C16 (palmitoyl-compounds) and C18 (stearoyl-compounds) in the plastidic acyl-ACP pool by inhibition of KASII expression would change the yield and composition of wax esters via substrate preference of the introduced enzymes. Here, we report that transient inhibition of KASII expression by three different RNAi constructs in leaves of N. benthamiana results in almost complete inhibition of KASII expression. The transient RNAi approach led to a shift of carbon flux from a pool of C18 fatty acids to C16, which significantly increased wax ester production in AtFAR6-containing combinations. The results demonstrate that transient inhibition of KASII in vegetative tissues of higher plants enables metabolic studies towards industrial production of lipids such as wax esters with specific quality and composition. PMID:26063537

  12. Transient silencing of the KASII genes is feasible in Nicotiana benthamiana for metabolic engineering of wax ester composition.

    PubMed

    Aslan, Selcuk; Hofvander, Per; Dutta, Paresh; Sitbon, Folke; Sun, Chuanxin

    2015-06-11

    The beta-ketoacyl-ACP synthase II (KASII) is an enzyme in fatty acid biosynthesis, catalyzing the elongation of 16:0-acyl carrier protein (ACP) to 18:0-ACP in plastids. Mutations in KASII genes in higher plants can lead to lethality, which makes it difficult to utilize the gene for lipid metabolic engineering. We demonstrated previously that transient expression of plastid-directed fatty acyl reductases and wax ester synthases could result in different compositions of wax esters. We hypothesized that changing the ratio between C16 (palmitoyl-compounds) and C18 (stearoyl-compounds) in the plastidic acyl-ACP pool by inhibition of KASII expression would change the yield and composition of wax esters via substrate preference of the introduced enzymes. Here, we report that transient inhibition of KASII expression by three different RNAi constructs in leaves of N. benthamiana results in almost complete inhibition of KASII expression. The transient RNAi approach led to a shift of carbon flux from a pool of C18 fatty acids to C16, which significantly increased wax ester production in AtFAR6-containing combinations. The results demonstrate that transient inhibition of KASII in vegetative tissues of higher plants enables metabolic studies towards industrial production of lipids such as wax esters with specific quality and composition.

  13. The composition of some Roman medicines: evidence for Pliny's Punic wax?

    PubMed

    Stacey, R J

    2011-10-01

    Residues from medicine containers in the collections of the British Museum have been investigated as part of a wider programme of scientific work on Roman surgical instruments. The cylindrical bronze containers are often described as instrument cases, but some contain materia medica, ranging from extensive extant remains of ancient preparations to possible minor deposits on the interior surfaces of the containers. Samples from seven residues have been analysed by gas chromatography-mass spectrometry (GC-MS) to identify lipid, resin and carbohydrate components and by X-ray fluorescence and Raman spectroscopy to characterise inorganic materials. The results have provided evidence for ointments and powders or pills consistent with a medical purpose. The ingredients identified include beeswax, fat, conifer resin and gum-derived sugars, plus elemental carbon and lead and zinc salts. Particularly significant were the varied compositions of residues from four sections of a multi-compartment container. In one of these compartments, the beeswax seems to have been prepared as the 'Punic wax' described by Pliny. Experimental preparation of Punic wax following Pliny's method was undertaken in the laboratory and the product analysed to compare with the ointment residues. This paper discusses the GC-MS results of both the experimental material and the archaeological residues and their significance for the interpretation of the past intended applications of the medicines and the use of the containers.

  14. Hydrogen isotope composition of leaf wax n-alkanes in glaucous and non-glaucous varieties of wheat (Triticum spp.)

    NASA Astrophysics Data System (ADS)

    Pedentchouk, Nikolai; Eley, Yvette; Frizell-Armitage, Amelia; Uauy, Cristobal

    2015-04-01

    The use of the 2H/1H composition of terrestrial plants in climate and ecology studies depends on fundamental understanding of the processes within the plant that control fractionation of these two isotopes. Little is currently known about the extent of 2H/1H fractionation at different steps of biosynthesis, after the initial H uptake following leaf water photolysis. Knowing this effect is particularly important when seeking to interpret the 2H/1H composition of leaf wax biomarkers from plants that differ in the amount and type of individual compound classes in their leaf waxes. The purpose of this study was to investigate the link between the quantity and distribution of n-alkyl lipids in leaf waxes and their isotopic composition. We used a genetic approach to suppress glaucousness in 2 varieties of wheat (Alchemy and Malacca), which resulted in glaucous and non-glaucous phenotypes of both varieties. Both phenotypes were then grown outdoors under identical environmental conditions in central Norfolk, UK. At the end of the growing season, the plants were sampled for soil water, leaf water, and leaf wax isotopic measurements. Comparison of the leaf wax composition of the non-glaucous and glaucous phenotypes revealed that the non-glaucous varieties were characterised by the absence of diketones and a greater concentration of n-alkanes and primary alcohols.. Our results showed very small differences between glaucous and non-glaucous varieties with regard to soil (mean values, <2 per mil) and leaf (<1 per mil) water 2H/1H. Conversely, there was 15-20 and 10-15 per mil 2H-depletion in the C29 and C31 n-alkanes, respectively, from the non-glaucous phenotype. This 2H-depletion in the non-glaucous phenotype demonstrated that the suppression of diketone production and the increase in n-alkane and primary alcohol concentrations are linked with a shift in the 2H/1H composition of n-alkanes. The initial results of this work suggest that plants using the same environmental water

  15. Ear wax

    MedlinePlus

    The ear canal is lined with hair follicles and glands that produce a waxy oil called cerumen. The wax will most ... Wax can build up and block the ear canal. Wax blockage is one of the most common ...

  16. Wax esters of different compositions produced via engineering of leaf chloroplast metabolism in Nicotiana benthamiana.

    PubMed

    Aslan, Selcuk; Sun, Chuanxin; Leonova, Svetlana; Dutta, Paresh; Dörmann, Peter; Domergue, Frédéric; Stymne, Sten; Hofvander, Per

    2014-09-01

    In a future bio-based economy, renewable sources for lipid compounds at attractive cost are needed for applications where today petrochemical derivatives are dominating. Wax esters and fatty alcohols provide diverse industrial uses, such as in lubricant and surfactant production. In this study, chloroplast metabolism was engineered to divert intermediates from de novo fatty acid biosynthesis to wax ester synthesis. To accomplish this, chloroplast targeted fatty acyl reductases (FAR) and wax ester synthases (WS) were transiently expressed in Nicotiana benthamiana leaves. Wax esters of different qualities and quantities were produced providing insights to the properties and interaction of the individual enzymes used. In particular, a phytyl ester synthase was found to be a premium candidate for medium chain wax ester synthesis. Catalytic activities of FAR and WS were also expressed as a fusion protein and determined functionally equivalent to the expression of individual enzymes for wax ester synthesis in chloroplasts.

  17. Alteration of Wax Ester Content and Composition in Euglena gracilis with Gene Silencing of 3-ketoacyl-CoA Thiolase Isozymes.

    PubMed

    Nakazawa, Masami; Andoh, Hiroko; Koyama, Keiichiro; Watanabe, Yomi; Nakai, Takeo; Ueda, Mitsuhiro; Sakamoto, Tatsuji; Inui, Hiroshi; Nakano, Yoshihisa; Miyatake, Kazutaka

    2015-05-01

    Euglena gracilis produces wax ester under hypoxic and anaerobic culture conditions with a net synthesis of ATP. In wax ester fermentation, fatty acids are synthesized by reversing beta-oxidation in mitochondria. A major species of wax ester produced by E. gracilis is myristyl myristate (14:0-14:0Alc). Because of its shorter carbon chain length with saturated compounds, biodiesel produced from E. gracilis wax ester may have good cold flow properties with high oxidative stability. We reasoned that a slight metabolic modification would enable E. gracilis to produce a biofuel of ideal composition. In order to produce wax ester with shorter acyl chain length, we focused on isozymes of the enzyme 3-ketoacyl-CoA thiolase (KAT), a condensing enzyme of the mitochondrial fatty acid synthesis pathway in E. gracilis. We performed a gene silencing study of KAT isozymes in E. gracilis. Six KAT isozymes were identified in the E. gracilis EST database, and silencing any three of them (EgKAT1-3) altered the wax ester amount and composition. In particular, silencing EgKAT1 induced a significant compositional shift to shorter carbon chain lengths in wax ester. A model fuel mixture inferred from the composition of wax ester in EgKAT1-silenced cells showed a significant decrease in melting point compared to that of the control cells.

  18. Composition of cuticular waxes coating flag leaf blades and peduncles of Triticum aestivum cv. Bethlehem.

    PubMed

    Racovita, Radu C; Hen-Avivi, Shelly; Fernandez-Moreno, Josefina-Patricia; Granell, Antonio; Aharoni, Asaph; Jetter, Reinhard

    2016-10-01

    The work herein presents comprehensive analyses of the cuticular wax mixtures covering the flag leaf blade and peduncle of bread wheat (Triticum aestivum) cv. Bethlehem. Overall, Gas Chromatography-Mass Spectrometry and Flame Ionization Detection revealed a wax coverage of flag leaf blades (16 μg/cm(2)) a third that of peduncles (49 μg/cm(2)). Flag leaf blade wax was dominated by 1-alkanols, while peduncle wax contained primarily β-diketone and hydroxy-β-diketones, thus suggesting differential regulation of the acyl reduction and β-diketone biosynthetic pathways in the two analyzed organs. The characteristic chain length distributions of the various wax compound classes are discussed in light of their individual biosynthetic pathways and biosynthetic relationships between classes. Along with previously reported wheat wax compound classes (fatty acids, 1-alkanols, 1-alkanol esters, aldehydes, alkanes, β-diketone, hydroxy-β-diketones, alkylresorcinols and methyl alkylresorcinols), esters of 2-alkanols and three types of aromatic esters (benzyl, phenethyl and p-hydroxyphenethyl) are also reported. In particular, 2-heptanol esters were identified. Detailed analyses of the isomer distributions within 1-alkanol and 2-alkanol ester homologs revealed distinct patterns of esterified acids and alcohols, suggesting several wax ester synthases with very different substrate preferences in both wheat organs. Terpenoids, including two terpenoid esters, were present only in peduncle wax. PMID:27264640

  19. Tracing subsoil organic matter compositional changes by radiocarbon and plant leaf wax distributional changes

    NASA Astrophysics Data System (ADS)

    John, Stephan; Angst, Gerrit; Mueller, Carsten W.; Heinze, Stefanie; Marschner, Bernd; Rethemeyer, Janet

    2014-05-01

    The carbon pool in subsoils is thought to be considerably larger than in the upper 30 cm. However, factors like turnover, stabilization and distribution of organic matter (OM) are less well understood than in topsoils. The investigation of changes in OM composition with depth enables a better understanding of the peculiarity of subsoil OM in contrast to the already extensively studied topsoil OM. Analysis of long chained n-alkanes and n-fatty acids in soil profiles sampled in high resolution, combined with radiocarbon data of bulk soil, is a tool to demonstrate spatial distribution and the degradation of plant leaf wax-derived material as a defined source of soil organic. We analysed the OM in 3.15 m long soil transects under an even aged European beech (Fagus sylvatica L.) forest in Northern Germany (Grinderwald, Lower Saxony) for lipid and radiocarbon analysis. Samples were taken from a grid raster with eight sampling points increasing in distance to the main tree (45cm grid dimension) and from five depths (10, 35, 60, 85, 110 cm) resulting 40 samples per transect. Organic carbon contents in the podzolic Cambisol decrease from 1.69 % in the A-horizon to 0.02 % in the C-horizon at 110 cm depth. The distribution of organic carbon contents shows no significant trend with increasing distance to the beeches in all transects. We compare the distribution of long-chain n-alkanes (C27, C29 and C31) and n-fatty acids (>C20), known as components mainly derived from leaf waxes of higher plants, in the different transect/depth intervals. Distributional and quantitative changes in the transects, combined with bulk soil 14C-analyses, reflecting apparent mean residence time of OM, are used to identify how fast OM is degraded from surface to subsoil horizons. Furthermore, spatial OM heterogeneity in the transects is investigated. We expect a more significant heterogeneity in the lipid distribution and nearly similar decreasing contents for n-alkanes as well as n-fatty acids

  20. Reconstructing hydrologic changes in Indonesia by deuterium isotope compositions of plant waxes

    NASA Astrophysics Data System (ADS)

    Gesierich, K.; Schefuss, E.; Hebbeln, D.; Mohtadi, M.; Behling, H.; Jennerjahn, T. C.

    2012-12-01

    The Indonesian region plays an essential role as a center of atmospheric heat and moisture source of the Earth's climate system and is known for its characteristic abundant rainfall throughout the year. Here, we examine hydrological variability during the Late Quaternary in Indonesia from a NW-SE transect from Sumatra to Flores based on compound-specific plant leaf wax isotope measurements. The five investigated coring sites are located on the continental shelf in the Indian Ocean, spanning the last 20 ka. The transect covers a pronounced gradient in climate and vegetation. Sumatra is located in an area with sufficient rainfall throughout the year, whereas in eastward direction rainfall decreases and a dry season exist. Compound specific analyses of n-alkanes of plant leaf waxes (D/H and δ13C) give insights into continental hydrologic changes and the distribution of C3 and C4 vegetation. We compared data from 4 time intervals that characterize the last glacial maximum (20 ka), the Heinrich event 1 (15 ka) and the Holocene with maximum in summer insolation (8 ka) and minimum in summer insolation at 30°N (3 ka). Our results show that estimated D/H values of precipitation, i.e., by vegetation-correction of compound-specific D/H values of n-alkanes, in the Holocene (3 and 8 ka) coincide with modern averaged D/H values of rain water. In contrast, during glacial times the results deviate significantly to lighter values, which would indicate higher rainfall intensity due to the amount-effect. The largest deviations to lighter values are found in the Java region, whereas Sumatra and Flores shows only slightly changes. Previous studies and the δ13C values of the n-alkanes, however, suggest that climate in Indonesia, especially in the eastern part, was drier during the last glacial, including Heinrich 1, and C4 grasses were more abundant, respectively. This discrepancy must be explained by other effects on the isotopic composition of rainfall that occurred in the

  1. Developmental Changes in Composition and Morphology of Cuticular Waxes on Leaves and Spikes of Glossy and Glaucous Wheat (Triticum aestivum L.)

    PubMed Central

    Chai, Guaiqiang; Li, Chunlian; Hu, Yingang; Chen, Xinhong; Wang, Zhonghua

    2015-01-01

    The glossy varieties (A14 and Jing 2001) and glaucous varieties (Fanmai 5 and Shanken 99) of wheat (Triticum aestivum L.) were selected for evaluation of developmental changes in the composition and morphology of cuticular waxes on leaves and spikes. The results provide us with two different wax development patterns between leaf and spike. The general accumulation trend of the total wax load on leaf and spike surfaces is first to increase and then decrease during the development growth period, but these changes were caused by different compound classes between leaf and spike. Developmental changes of leaf waxes were mainly the result of variations in composition of alcohols and alkanes. In addition, diketones were the third important contributor to the leaf wax changes in the glaucous varieties. Alkanes and diketones were the two major compound classes that caused the developmental changes of spike waxes. For leaf waxes, β- and OH-β-diketones were first detected in flag leaves from 200-day-old plants, and the amounts of β- and OH-β-diketones were significantly higher in glaucous varieties compared with glossy varieties. In spike waxes, β-diketone existed in all varieties, but OH-β-diketone was detectable only in the glaucous varieties. Unexpectedly, the glaucous variety Fanmai 5 yielded large amounts of OH-β-diketone. There was a significant shift in the chain length distribution of alkanes between early stage leaf and flag leaf. Unlike C28 alcohol being the dominant chain length in leaf waxes, the dominant alcohol chain length of spikes was C24 or C26 depending on varieties. Epicuticular wax crystals on wheat leaf and glume were comprised of platelets and tubules, and the crystal morphology changed constantly throughout plant growth, especially the abaxial leaf crystals. Moreover, our results suggested that platelets and tubules on glume surfaces could be formed rapidly within a few days. PMID:26506246

  2. Wax poisoning

    MedlinePlus

    Crayons poisoning ... This ingredient is found in: Crayons Candles Canning wax Note: This list may not be all-inclusive. ... If a child eats a small amount of crayon, the wax will pass through the child's system ...

  3. Comparative analysis of surface wax in mature fruits between Satsuma mandarin (Citrus unshiu) and 'Newhall' navel orange (Citrus sinensis) from the perspective of crystal morphology, chemical composition and key gene expression.

    PubMed

    Wang, Jinqiu; Hao, Haohao; Liu, Runsheng; Ma, Qiaoli; Xu, Juan; Chen, Feng; Cheng, Yunjiang; Deng, Xiuxin

    2014-06-15

    Surface wax of mature Satsuma mandarin (Citrus unshiu) and 'Newhall' navel orange (Citrus sinensis) was analysed by crystal morphology, chemical composition, and gene expression levels. The epicuticular and total waxes of both citrus cultivars were mostly composed of aldehydes, alkanes, fatty acids and primary alcohols. The epicuticular wax accounted for 80% of the total wax in the Newhall fruits and was higher than that in the Satsuma fruits. Scanning electron microscopy showed that larger and more wax platelets were deposited on the surface of Newhall fruits than on the Satsuma fruits. Moreover, the expression levels of genes involved in the wax formation were consistent with the biochemical and crystal morphological analyses. These diversities of fruit wax between the two cultivars may contribute to the differences of fruit postharvest storage properties, which can provide important information for the production of synthetic wax for citrus fruits.

  4. Coupled isotopes of plant wax and hemicellulose markers record information on relative humidity and isotopic composition of precipitation

    NASA Astrophysics Data System (ADS)

    Tuthorn, M.; Zech, R.; Ruppenthal, M.; Oelmann, Y.; Kahmen, A.; del Valle, H. F.; Eglinton, T.; Zech, M.

    2015-02-01

    The δ2H isotopic composition of leaf waxes is used increasingly for paleohydrological and -climate reconstructions. However, it is challenging to disentangle past changes in the isotopic composition of precipitation and changes in evapotranspirative enrichment of leaf water. We analyzed δ2H on n-alkanes and fatty acids in topsoils along a climate transect in Argentina, for which we had previously measured δ18O on plant-derived sugars. Our results indicate that leaf wax biomarker δ2H values (δ2Hlipids) primarily reflect δ2Hsource water (precipitation), but are modulated by evapotranspirative enrichment. A mechanistic model is able to produce the main trends in δ2Hlipids along the transect, but seems to slightly underestimate evapotranspirative enrichment in arid regions and overestimate it in grass-dominated ecosystems. Furthermore, the (i) coupling of the δ2Hlipid and δ18Osugar biomarker results and (ii) application of biosynthetic fractionation factors allows calculating the δ2H-δ18O isotopic composition of leaf water along the transect. This also yields the deuterium excess (d excess) of leaf water, which mainly reflects evapotranspirative enrichment, and can be used to model relative air humidity (RH). The high correlation of modeled (reconstructed based on biomarker results) and measured RH, as well as the good agreement between modeled and actual δ2H and δ18O of precipitation along the transect lends support to the coupled δ2Hlipid and δ18Osugar biomarker approach for future paleoclimate research.

  5. Wax Reinforces Honeycomb During Machining

    NASA Technical Reports Server (NTRS)

    Towell, Timothy W.; Fahringer, David T.; Vasquez, Peter; Scheidegger, Alan P.

    1995-01-01

    Method of machining on conventional metal lathe devised for precise cutting of axisymmetric contours on honeycomb cores made of composite (matrix/fiber) materials. Wax filling reinforces honeycomb walls against bending and tearing while honeycomb being contoured on lathe. Innovative method of machining on lathe involves preparation in which honeycomb is placed in appropriate fixture and the fixture is then filled with molten water-soluble wax. Number of different commercial waxes have been tried.

  6. Investigation into the Coating and Desensitization Effect on HNIW of Paraffin Wax/Stearic Acid Composite System

    NASA Astrophysics Data System (ADS)

    Wang, Dong-Xu; Chen, Shu-Sen; Jin, Shao-Hua; Shu, Qing-Hai; Jiang, Zhen-Ming; Shang, Feng-Qin; Li, Jin-Xin

    2016-01-01

    2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (HNIW) was bonded by fluorine rubber and then desensitized by paraffin wax (PW), stearic acid (SA), and a PW/SA composite system using an aqueous suspension method. The coating and desensitization effects of the composite systems on HNIW and the influence of the addition of SA on the mechanical properties of the coated HNIW samples were studied. In addition, the PW/SA composite solution was simulated using a molecular dynamics method, and the relationship between the desensitization effect on HNIW and the properties of the composite solution was investigated. The results showed that the PW/SA composite system, of which the desensitization effect on HNIW was between those of the two desensitizers, could effectively coat HNIW and that the composite solution had the most stable and well-distributed state when using benzene as solvent with the mass ratio of PW/SA equal to 7/3 or 3/7, thus resulting in the best desensitization effect on HNIW. Moreover, the addition of stearic acid was successful in enhancing the mechanical properties of the coated HNIW samples.

  7. Practical Analysis of materials with depth varying compositions using FT-IR photoacoustic spectroscopy (PAS)

    SciTech Connect

    J.F. McClelland; R.W. Jones; Siquan Luo

    2004-09-30

    FT-IR photoacoustic spectroscopy (PAS) is discussed as a nondestructive method to probe the molecular composition of materials versus depth on the basis of the analysis of layers of experimentally controllable thickness, which are measured from the sample surface to depths of some tens of micrometers, depending on optical and thermal properties. Computational methods are described to process photoacoustic amplitude and phase spectra for both semi-quantitative and quantitative depth analyses. These methods are demonstrated on layered and gradient samples.

  8. Evaluation of Polymerization Efficacy in Composite Resins via FT-IR Spectroscopy and Vickers Microhardness Test

    PubMed Central

    Jafarzadeh, Tahereh-Sadat; Erfan, Mohammad; Behroozibakhsh, Marjan; Fatemi, Mostafa; Masaeli, Reza; Rezaei, Yashar; Bagheri, Hossein; Erfan, Yasaman

    2015-01-01

    Background and aims. Polymerization efficacy affects the properties and performance of composite resin restorations.The purpose of this study was to evaluate the effectiveness of polymerization of two micro-hybrid, two nano-hybrid and one nano-filled ormocer-based composite resins, cured by two different light-curing systems, using Fourier transformation infrared (FT-IR) spectroscopy and Vickers microhardness testing at two different depths (top surface, 2 mm). Materials and methods. For FT-IR spectrometry, five cylindrical specimens (5mm in diameter × 2 mm in length) were prepared from each composite resin using Teflon molds and polymerized for 20 seconds. Then, 70-μm wafers were sectioned at the top surface and at2mm from the top surface. The degree of conversion for each sample was calculated using FT-IR spectroscopy. For Vickers micro-hardness testing, three cylindrical specimens were prepared from each composite resin and polymerized for 20 seconds. The Vickers microhardness test (Shimadzu, Type M, Japan) was performed at the top and bottom (depth=2 mm) surfaces of each specimen. Three-way ANOVA with independent variables and Tukey tests were performed at 95% significance level. Results. No significant differences were detected in degree of conversion and microhardness between LED and QTH light-curing units except for the ormocer-based specimen, CeramX, which exhibited significantly higher DC by LED. All the composite resins showed a significantly higher degree of conversion at the surface. Microhardness was not significantly affected by depth, except for Herculite XRV Ultra and CeramX, which showed higher values at the surface. Conclusion. Composite resins containing nano-particles generally exhibited more variations in degree of conversion and microhardness. PMID:26889359

  9. Variability of biomass chemical composition and rapid analysis using FT-NIR techniques

    SciTech Connect

    Liu, Lu; Ye, Philip; Womac, A.R.; Sokhansanj, Shahabaddine

    2010-04-01

    A quick method for analyzing the chemical composition of renewable energy biomass feedstock was developed by using Fourier transform near-infrared (FT-NIR) spectroscopy coupled with multivariate analysis. The study presents the broad-based model hypothesis that a single FT-NIR predictive model can be developed to analyze multiple types of biomass feedstock. The two most important biomass feedstocks corn stover and switchgrass were evaluated for the variability in their concentrations of the following components: glucan, xylan, galactan, arabinan, mannan, lignin, and ash. A hypothesis test was developed based upon these two species. Both cross-validation and independent validation results showed that the broad-based model developed is promising for future chemical prediction of both biomass species; in addition, the results also showed the method's prediction potential for wheat straw.

  10. A comparison of the composition of epicuticular wax from red raspberry (Rubus idaeus L.) and hawthorn (Crataegus monogyna Jacq.) flowers.

    PubMed

    Griffiths, D W; Robertson, G W; Shepherd, T; Birch, A N; Gordon, S C; Woodford, J A

    2000-09-01

    Epicuticular waxes have been characterised from the flowers of raspberry and hawthorn, on both of which adult raspberry beetles (Byturus tomentosus) can feed. The flower wax from both species had similar alkane profiles and also contained long-chain alcohols, aldehydes and fatty acids. The range of the carbon numbers detected for these classes of compounds was broadly similar in both but the relative amounts of each differed between species. Raspberry flower wax also contained fatty acid methyl esters, a group of compounds that has rarely been detected in plant epicuticular waxes, however, these were not observed in hawthorn flower wax. Long-chain alcohol-fatty acid esters with carbon numbers ranging from C36 to C48 were also detected in both plant species. However, an examination of their constituent acids indicated that in hawthorn the esters based on the C16 fatty acid predominated, whilst in raspberry flower wax, esters based on the C20 fatty acid were most abundant. Both species also contained pentacyclic triterpenoids, which accounted for, on average, over 16 and 48% of the total wax extracted from raspberry and hawthorn flowers respectively. In the former, ursolic and oleanolic acids accounted for over 90% of the pentacyclic triterpenes, whilst hawthorn flower wax, in addition to containing these acids, also contained high relative concentrations of both free and esterified alpha- and beta-amyrins.

  11. The stable hydrogen isotopic composition of sedimentary plant waxes as quantitative proxy for rainfall in the West African Sahel

    NASA Astrophysics Data System (ADS)

    Niedermeyer, Eva M.; Forrest, Matthew; Beckmann, Britta; Sessions, Alex L.; Mulch, Andreas; Schefuß, Enno

    2016-07-01

    Various studies have demonstrated that the stable hydrogen isotopic composition (δD) of terrestrial leaf waxes tracks that of precipitation (δDprecip) both spatially across climate gradients and over a range of different timescales. Yet, reconstructed estimates of δDprecip and corresponding rainfall typically remain largely qualitative, due mainly to uncertainties in plant ecosystem net fractionation, relative humidity, and the stability of the amount effect through time. Here we present δD values of the C31n-alkane (δDwax) from a marine sediment core offshore the Northwest (NW) African Sahel covering the past 100 years and overlapping with the instrumental record of rainfall. We use this record to investigate whether accurate, quantitative estimates of past rainfall can be derived from our δDwax time series. We infer the composition of vegetation (C3/C4) within the continental catchment area by analysis of the stable carbon isotopic composition of the same compounds (δ13Cwax), calculated a net ecosystem fractionation factor, and corrected the δDwax time series accordingly to derive δDprecip. Using the present-day relationship between δDprecip and the amount of precipitation in the tropics, we derive quantitative estimates of past precipitation amounts. Our data show that (a) vegetation composition can be inferred from δ13Cwax, (b) the calculated net ecosystem fractionation represents a reasonable estimate, and (c) estimated total amounts of rainfall based on δDwax correspond to instrumental records of rainfall. Our study has important implications for future studies aiming to reconstruct rainfall based on δDwax; the combined data presented here demonstrate that it is feasible to infer absolute rainfall amounts from sedimentary δDwax in tandem with δ13Cwax in specific depositional settings.

  12. Leaf wax composition and carbon isotopes vary among major conifer groups

    NASA Astrophysics Data System (ADS)

    Diefendorf, Aaron F.; Leslie, Andrew B.; Wing, Scott L.

    2015-12-01

    Leaf waxes (e.g. n-alkanes, n-alkanoic acids) and their carbon isotopes (δ13C) are commonly used to track past changes in the carbon cycle, water availability, and plant ecophysiology. Previous studies indicated that conifers have lower n-alkane concentrations than angiosperms and that 13C fractionation during n-alkane synthesis (εn-alkane) is smaller than in angiosperms. These prior studies, however, sampled a limited phylogenetic and geographic subset of conifers, leaving out many important subtropical and Southern Hemisphere groups that were once widespread and common components of fossil assemblages. To expand on previous work, we collected 43 conifer species (and Ginkgo biloba) from the University of California Botanical Garden at Berkeley, sampling all extant conifer families and almost two-thirds of extant genera. We find that Pinaceae, including many North American species used in previous studies, have very low or no n-alkanes. However, other conifer groups have significant concentrations of n-alkanes, especially Southern Hemisphere Araucariaceae and Podocarpaceae (monkey puzzles, Norfolk Island pines, and yellowwoods), and many species of Cupressaceae (junipers and relatives). Within the Cupressaceae, we find total n-alkane concentrations are high in subfamilies Cupressoideae and Callitroideae, but significantly lower in the early diverging taxodioid lineages (including bald cypress and redwood). Individual n-alkane chain lengths have a weak phylogenetic signal, except for n-C29 alkane, but when combined using average chain length (ACL), a strong phylogenetic signal emerges. The strong phylogenetic signal in ACL, observed in the context of a common growth environment for all plants we sampled, suggests that ACL is strongly influenced by factors other than climate. An analysis of εn-alkane indicates a strong phylogenetic signal in which the smallest biosynthetic fractionation occurs in Pinaceae and the largest in Taxaceae (yews and relatives). The

  13. Separation of Fischer-Tropsch wax from catalyst by supercritical fluid extraction. Technical progress report, January--March 1995

    SciTech Connect

    Thies, M.C.

    1995-08-01

    Objective is to evaluate the potential of supercritical fluid extraction for separating the catalyst slurry of a Fischer-Tropsch (F- T) slurry bubble column reactor into a wax and a concentrated catalyst slurry that is ready for recycle/regeneration. The automated apparatus was evaluated using a toluene-petroleum pitch system. The Statistical Associating Fluid Theory (SAFT) equation will be used to fit the VLE and LLE data for F-T wax-solvent systems; this equation was successful in predicting both phase compositions and average molecular weight distributions.

  14. Wax and cutin mutants of Arabidopsis: Quantitative characterization of the cuticular transport barrier in relation to chemical composition.

    PubMed

    Sadler, Christina; Schroll, Bettina; Zeisler, Viktoria; Waßmann, Friedrich; Franke, Rochus; Schreiber, Lukas

    2016-09-01

    Using (14)C-labeled epoxiconazole as a tracer, cuticular permeability of Arabidopsis thaliana leaves was quantitatively measured in order to compare different wax and cutin mutants (wax2, cut1, cer5, att1, bdg, shn3 and shn1) to the corresponding wild types (Col-0 and Ws). Mutants were characterized by decreases or increases in wax and/or cutin amounts. Permeances [ms(-1)] of Arabidopsis cuticles either increased in the mutants compared to wild type or were not affected. Thus, genetic changes in wax and cutin biosynthesis in some of the investigated Arabidopsis mutants obviously impaired the coordinated cutin and wax deposition at the outer leaf epidermal cell wall. As a consequence, barrier properties of cuticles were significantly decreased. However, increasing cutin and wax amounts by genetic modifications, did not automatically lead to improved cuticular barrier properties. As an alternative approach to the radioactive transport assay, changes in chlorophyll fluorescence were monitored after foliar application of metribuzine, an herbicide inhibiting electron transport in chloroplasts. Since both, half-times of photosynthesis inhibition as well as times of complete inhibition, in fact correlated with (14)C-epoxiconazole permeances, different rates of decline of photosynthetic yield between mutants and wild type must be a function of foliar uptake of the herbicide across the cuticle. Thus, monitoring changes in chlorophyll fluorescence, instead of conducting radioactive transport assays, represents an easy-to-handle and fast alternative evaluating cuticular barrier properties of different genotypes. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.

  15. HOT WAX.

    PubMed

    Schneberk, Todd; Valenzuela, Rolando G; Sterling, Garrett; Mallon, William K

    2015-09-01

    High-potency marijuana wax smoked via dabbing is a newly encountered phenomenon with relevance to prehospital care providers and emergency physicians.The extract is only recently described in current peer-reviewed literature. The drug may produce paranoia and psychosis and mimic psychiatric problems. The synthetic process for this drug poses a risk for both fire and explosions creating burns and blast injuries. These four cases were encountered in a single ED in Los Angeles in a three-week period, suggesting this could be the tip of an emerging public health problem. All four of these patients were complex cases requiring advanced imaging and ICU care. Emergency personnel need to appreciate this new trend and the implications for pre-hospital care, disposition and ED treatment of these patients. PMID:26554181

  16. Mammalian Wax Biosynthesis

    PubMed Central

    Cheng, Jeffrey B.; Russell, David W.

    2009-01-01

    Wax monoesters are synthesized by the esterification of fatty alcohols and fatty acids. A mammalian enzyme that catalyzes this reaction has not been isolated. We used expression cloning to identify cDNAs encoding a wax synthase in the mouse preputial gland. The wax synthase gene is located on the X chromosome and encodes a member of the acyltransferase family of enzymes that synthesize neutral lipids. Expression of wax synthase in cultured cells led to the formation of wax monoesters from straight chain saturated, unsaturated, and polyunsaturated fatty alcohols and acids. Polyisoprenols also were incorporated into wax monoesters by the enzyme. The wax synthase had little or no ability to synthesize cholesteryl esters, diacylglycerols, or triacylglycerols, whereas other acyltransferases, including the acyl-CoA:monoacylglycerol acyltransferase 1 and 2 enzymes and the acyl-CoA:diacylglycerol acyltransferase 1 and 2 enzymes, exhibited modest wax monoester synthesis activities. Confocal light microscopy indicated that the wax synthase was localized in membranes of the endoplasmic reticulum. Wax synthase mRNA was abundant in tissues rich in sebaceous glands such as the preputial gland and eyelid and was present at lower levels in other tissues. Coexpression of cDNAs specifying fatty acyl-CoA reductase 1 and wax synthase led to the synthesis of wax monoesters. The data suggest that wax monoester synthesis in mammals involves a two step biosynthetic pathway catalyzed by fatty acyl-CoA reductase and wax synthase enzymes. PMID:15220349

  17. Identification of avian wax synthases

    PubMed Central

    2012-01-01

    Background Bird species show a high degree of variation in the composition of their preen gland waxes. For instance, galliform birds like chicken contain fatty acid esters of 2,3-alkanediols, while Anseriformes like goose or Strigiformes like barn owl contain wax monoesters in their preen gland secretions. The final biosynthetic step is catalyzed by wax synthases (WS) which have been identified in pro- and eukaryotic organisms. Results Sequence similarities enabled us to identify six cDNAs encoding putative wax synthesizing proteins in chicken and two from barn owl and goose. Expression studies in yeast under in vivo and in vitro conditions showed that three proteins from chicken performed WS activity while a sequence from chicken, goose and barn owl encoded a bifunctional enzyme catalyzing both wax ester and triacylglycerol synthesis. Mono- and bifunctional WS were found to differ in their substrate specificities especially with regard to branched-chain alcohols and acyl-CoA thioesters. According to the expression patterns of their transcripts and the properties of the enzymes, avian WS proteins might not be confined to preen glands. Conclusions We provide direct evidence that avian preen glands possess both monofunctional and bifunctional WS proteins which have different expression patterns and WS activities with different substrate specificities. PMID:22305293

  18. HL-20 Wax Model

    NASA Technical Reports Server (NTRS)

    1993-01-01

    A numerically machined wax pattern of the NASA HL-20 orbital re-entry lifting body was cut from a CAD/CAM file. This nine-inch wax model was later used in a lost wax investment casting process to replicate the pattern in ceramic for wind-tunnel aero-heating studies

  19. The chemical oxidation and refinement of raw Fischer-Tropsch wax

    SciTech Connect

    Zhu Jisheng; Chen Languang; Sun Shuhe; Cheng Shaoxin

    1995-12-31

    Raw Fischer-Tropsch wax (FT wax) produced from the pilot plant (100t/a, Daixian, Shanxi Province) and the demonstration plant (2,000t/a, Jincheng, Shanxi Province) of coal-based synthetic gasoline process was refined by chemical oxidation. The properties of refined FT wax were greatly improved. The results show that the refined wax with very high melting point (108 C) and satisfactory hardness (penetration about 5, 25 C 100g/5s) consists of a large amount of paraffins, but a minute amount of acids, alcohols and other organic compounds.

  20. Application of FT-IR spectroscopy for control of the medium composition during the biodegradation of nitro aromatic compounds.

    PubMed

    Grube, Mara; Muter, Olga; Strikauska, Silvija; Gavare, Marita; Limane, Baiba

    2008-11-01

    Previous studies showed that cabbage leaf extract (CLE) added to the growth medium can noticeably promote the degradation of nitro aromatic compounds by specific consortium of bacteria upon their growth. For further development of the approach for contaminated soil remediation it was necessary to evaluate the qualitative and/or quantitative composition of different origin CLE and their relevance on the growth of explosives-degrading bacteria. Six CLE (different by species, cultivars and harvesting time) were tested and used as additives to the growth medium. It was shown that nitro aromatic compounds can be identified in the FT-IR absorption spectra by the characteristic band at 1,527 cm(-1), and in CLE by the characteristic band at 1,602 cm(-1). The intensity of the CLE band at 1,602 cm(-1) correlated with the concentration of total nitrogen (R2=0.87) and decreased upon the growth of bacteria. The content of nitrogen in CLE differed (0.22-1.00 vol.%) and significantly influenced the content of total carbohydrates (9.50-16.00% DW) and lipids [3.90-9.90% dry weight (DW)] accumulated in bacterial cells while the content of proteins was similar in all samples. Though this study showed quantitative differences in the composition of the studied CLE and the response of bacterial cells to the composition of the growth media, and proved the potential of this additive for remediation of contaminated soil. It was shown that analysis of CLE and monitoring of the conversion of nitro aromatic compounds can be investigated by FT-IR spectroscopy as well as by conventional chemical methods.

  1. FT-IR Photoacoustic Spectroscopy Applied to the Curing and Aging of Composites

    NASA Astrophysics Data System (ADS)

    Jones, Roger W.; Sweterlitsch, Jeffrey J.; Wagner, Anthony J.; McClelland, John F.; Hsu, David K.; Polis, Daniel L.; Sovinski, Marjorie F.

    2005-04-01

    Fourier-transform infrared photoacoustic spectroscopy has been applied to carbon-fiber composites to test whether bulk physical properties of the composites could be determined using the near-surface-sensitive photoacoustic approach. Both the cure levels of carbon fiber/cyanate ester composites and the interlaminar shear strengths of artificially aged carbon fiber/epoxy composites were successfully measured. Standard errors of cross validation were 3.46% cure for a sample set ranging from 8% to 95% cured and 1.60 MPa for aged samples with strengths ranging from 22 to 77 MPa.

  2. Can Stress-Induced Biochemical Differences drive Variation in the Hydrogen Isotope Composition of Leaf Wax n-Alkanes from Terrestrial Higher Plants?

    NASA Astrophysics Data System (ADS)

    Eley, Y.; Pedentchouk, N.; Dawson, L.

    2014-12-01

    Recent research has identified that interspecies variation in leaf wax n-alkane 2H/1H from plants growing at the same geographical location can exceed 100‰. These differences cannot easily be explained by mechanisms that influence the isotopic composition of leaf water. Biochemical processes are therefore likely to drive some of this variability. Currently, however, little is known about the relative importance of different biochemical processes in shaping n-alkane hydrogen isotope composition. To explore this issue, we combined n-alkane δ2H analysis with measurements of: (i) the percentage content of leaf C and N; and (ii) foliar δ15N, from seven plants growing at Stiffkey salt marsh, Norfolk, UK. These species differ biochemically in respect of the protective compounds they produce under salt or water stressed conditions, with monocots generally producing more carbohydrates, and dicots producing more nitrogenous compounds. We found that monocots had higher %C, while dicots had higher %N and 15N-enriched leaf tissue. We identified a systematic relationship between the nature of the dominant protective compound produced (carbohydrate vs. nitrogenous) and n-alkane 2H/1H: species with a greater proportion of carbohydrates have more negative δ2H values. These findings might imply that shifts in the relative contribution of H to pyruvate from NADPH (2H-depleted) and recycled carbohydrates (2H-enriched) can influence n-alkane δ2H. The 2H-depletion of monocot n-alkanes relative to dicots may therefore be due to a greater proportion of NADPH-derived H incorporated into pyruvate because of their enhanced demand for carbohydrates. The production of protective compounds in plant species is a common response to a range of abiotic stresses (e.g. high UV irradiation, drought, salinity, high/low temperature). Species-specific biochemical responses to stress could therefore influence n-alkane 2H/1H across a range of habitats. This study highlights the importance of detailed

  3. Growth factor controls on the distribution and carbon isotope composition of n-alkanes in leaf wax

    NASA Astrophysics Data System (ADS)

    Jia, C.; Xie, S.; Huang, X.

    2012-12-01

    Cuticular wax plays pivotal physiological and ecological roles in the interactions between plants and the environments in which they grow. Plant-derived long-chain alkanes are more resistant to decay than other biochemical polymers. n-Alkane distributions (Carbon Preference Index (CPI) values and Average Chain Length (ACL) values) and carbon isotopic values are used widely in palaeoenvironmental reconstruction. However, there is little information available on how growth stages of the plant might influence the abundance of n-alkanes in the natural environment. In this study, we analyzed n-alkane distributions and carbon isotope data from two tree species (Cinnamomum camphora (L.) Presl. and Liquidambar formosana Hance) collected monthly from 2009 to 2011 in Nanwang Shan, Wuhan, Hubei Province. CPI values for n-alkanes from C. camphora remained stable in autumn and winter but fluctuated dramatically during spring and autumn each year. Positive correlations between CPI values and the relative content of (C27+C29) were observed in both sun and shade leaves of C. camphora from April to July. In L. formosana, CPI values decreased gradually from April to December. A similar trend was observed in all three years suggesting that growth stages rather than temperature or relative humidity affected the CPI values on a seasonal timescale. In the samples of L. formosana ACL values were negatively correlated with CPI values in the growing season (from April to July) and positively correlated with CPI values in the other seasons. The δ13C values of C29 and C31 n-alkanes displayed more negative carbon isotopic values in autumn and winter compared with leaves sampled at the start of the growing season from both trees. The δ13C values of C29 and C31 n-alkanes of L. formosana decreased from April to December. These results demonstrate the importance of elucidating the growing factors that influence the distribution and δ13C values of alkanes in modern leaves prior to using CPI

  4. Wax hydroisomerization process

    SciTech Connect

    Degnan, T.F. Jr.; Landis, M.E.

    1991-02-26

    This patent describes a process for hydroisomerizing petroleum wax or synthetic paraffin wax, thereby reducing its pour point. It comprises: contacting the was with a hydroisomerization catalyst under sufficient hydroisomerization conditions. The catalyst comprises a layered titanate containing interspathic polymeric oxide. The catalyst further comprises a hydrogenating component selected from the group consisting of Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, and Pt.

  5. Significance of high-wax oil variability to Pacific Rim exploration and production

    SciTech Connect

    Carlson, R.M.K. ); Jacobson, S.R. )

    1996-01-01

    High-Wax oils are a class of paraffinic crudes that occur widely in Pacific Rim petroleum systems. New analytical technologies, particularly High Temperature Gas Chromatography (HTGC) show unexpected variations in the molecular weight ranges and concentrations of paraffin waxes within this class of crudes. These variations are source and maturity-related, providing paleoenvironmental and generative information useful to exploration. Paleoenvironmental factors revealed by high-wax oil HTGC source signatures can also help interpret the potential for nearby reservoirs. Furthermore, variations in wax compositions affect flow and organic scale-forming properties that impact the production economics of these oils. Lacustrine-sourced high-wax oils contain broad distributions of paraffin waxes ranging from C[sub 20] to C[sub 60] or higher. Various algae appear to be the source of higher molecular weight waxes in these oils. Paleoenvironmental factors, such as water salinities and paleoclimate, affect wax compositions of resulting lacustrine high-wax oils. Other terrestrial-sourced oils generated by paralic or nearshore marine source rocks show high concentrations of C[sub 25] to C[sub 35] waxes, but much lower distributions of higher molecular weight waxes. These high-wax oils appear to. contain waxes derived principally from terrestrial, higher plant materials. Results for high-wax petroleum systems in Australia, Indonesia, the Philippines and China illustrate these conclusions with examples ranging in age from Carboniferous-Permian to late Tertiary.

  6. Significance of high-wax oil variability to Pacific Rim exploration and production

    SciTech Connect

    Carlson, R.M.K.; Jacobson, S.R.

    1996-12-31

    High-Wax oils are a class of paraffinic crudes that occur widely in Pacific Rim petroleum systems. New analytical technologies, particularly High Temperature Gas Chromatography (HTGC) show unexpected variations in the molecular weight ranges and concentrations of paraffin waxes within this class of crudes. These variations are source and maturity-related, providing paleoenvironmental and generative information useful to exploration. Paleoenvironmental factors revealed by high-wax oil HTGC source signatures can also help interpret the potential for nearby reservoirs. Furthermore, variations in wax compositions affect flow and organic scale-forming properties that impact the production economics of these oils. Lacustrine-sourced high-wax oils contain broad distributions of paraffin waxes ranging from C{sub 20} to C{sub 60} or higher. Various algae appear to be the source of higher molecular weight waxes in these oils. Paleoenvironmental factors, such as water salinities and paleoclimate, affect wax compositions of resulting lacustrine high-wax oils. Other terrestrial-sourced oils generated by paralic or nearshore marine source rocks show high concentrations of C{sub 25} to C{sub 35} waxes, but much lower distributions of higher molecular weight waxes. These high-wax oils appear to. contain waxes derived principally from terrestrial, higher plant materials. Results for high-wax petroleum systems in Australia, Indonesia, the Philippines and China illustrate these conclusions with examples ranging in age from Carboniferous-Permian to late Tertiary.

  7. FT-Raman spectroscopy study of organic matrix degradation in nanofilled resin composite.

    PubMed

    Soares, Luís Eduardo Silva; Nahórny, Sídnei; Martin, Airton Abrahão

    2013-04-01

    This in vitro study evaluated the effect of light curing unit (LCU) type, mouthwashes, and soft drink on chemical degradation of a nanofilled resin composite. Samples (80) were divided into eight groups: halogen LCU, HS--saliva (control); HPT--Pepsi Twist®; HLC--Listerine®; HCP--Colgate Plax®; LED LCU, LS--saliva (control); LPT--Pepsi Twist®; LLC--Listerine®; LCP--Colgate Plax®. The degree of conversion analysis and the measure of the peak area at 2,930 cm-1 (organic matrix) of resin composite were done by Fourier-transform Raman spectroscopy (baseline, after 7 and 14 days). The data were subjected to multifactor analysis of variance (ANOVA) at a 95% confidence followed by Tukey's HSD post-hoc test. The DC ranged from 58.0% (Halogen) to 59.3% (LED) without significance. Differences in the peak area between LCUs were found after 7 days of storage in S and PT. A marked increase in the peak intensity of HLC and LLC groups was found. The soft-start light-activation may influence the chemical degradation of organic matrix in resin composite. Ethanol contained in Listerine® Cool Mint mouthwash had the most significant degradation effect. Raman spectroscopy is shown to be a useful tool to investigate resin composite degradation. PMID:23388411

  8. FT-Raman spectroscopy study of organic matrix degradation in nanofilled resin composite.

    PubMed

    Soares, Luís Eduardo Silva; Nahórny, Sídnei; Martin, Airton Abrahão

    2013-04-01

    This in vitro study evaluated the effect of light curing unit (LCU) type, mouthwashes, and soft drink on chemical degradation of a nanofilled resin composite. Samples (80) were divided into eight groups: halogen LCU, HS--saliva (control); HPT--Pepsi Twist®; HLC--Listerine®; HCP--Colgate Plax®; LED LCU, LS--saliva (control); LPT--Pepsi Twist®; LLC--Listerine®; LCP--Colgate Plax®. The degree of conversion analysis and the measure of the peak area at 2,930 cm-1 (organic matrix) of resin composite were done by Fourier-transform Raman spectroscopy (baseline, after 7 and 14 days). The data were subjected to multifactor analysis of variance (ANOVA) at a 95% confidence followed by Tukey's HSD post-hoc test. The DC ranged from 58.0% (Halogen) to 59.3% (LED) without significance. Differences in the peak area between LCUs were found after 7 days of storage in S and PT. A marked increase in the peak intensity of HLC and LLC groups was found. The soft-start light-activation may influence the chemical degradation of organic matrix in resin composite. Ethanol contained in Listerine® Cool Mint mouthwash had the most significant degradation effect. Raman spectroscopy is shown to be a useful tool to investigate resin composite degradation.

  9. Composition of the epicuticular waxes coating the adaxial side of Phyllostachys aurea leaves: Identification of very-long-chain primary amides.

    PubMed

    Racovita, Radu C; Jetter, Reinhard

    2016-10-01

    The present study presents comprehensive chemical analyses of cuticular wax mixtures of the bamboo Phyllostachys aurea. The epicuticular and intracuticular waxes were sampled selectively from the adaxial side of leaves on young and old plants and investigated by gas chromatography-mass spectrometry and flame ionization detection. The epi- and intracuticular layers on young and old leaves had wax loads ranging from 1.7 μg/cm(2) to 1.9 μg/cm(2). Typical very-long-chain aliphatic wax constituents were found with characteristic chain length patterns, including alkyl esters (primarily C48), alkanes (primarily C29), fatty acids (primarily C28 and C16), primary alcohols (primarily C28) and aldehydes (primarily C30). Alicyclic wax components were identified as tocopherols and triterpenoids, including substantial amounts of triterpenoid esters. Alkyl esters, alkanes, fatty acids and aldehydes were found in greater amounts in the epicuticular layer, while primary alcohols and most terpenoids accumulated more in the intracuticular wax. Alkyl esters occurred as mixtures of metamers, combining C20 alcohol with various acids into shorter ester homologs (C36C40), and a wide range of alcohols with C22 and C24 acids into longer esters (C42C52). Primary amides were identified, with a characteristic chain length profile peaking at C30. The amides were present exclusively in the epicuticular layer and thus at or near the surface, where they may affect plant-herbivore or plant-pathogen interactions. PMID:27402630

  10. FT-IR and FT-Raman studies of cross-linking processes with Ca(2+) ions, glutaraldehyde and microwave radiation for polymer composition of poly(acrylic acid)/sodium salt of carboxymethyl starch--part I.

    PubMed

    Grabowska, Beata; Sitarz, Maciej; Olejnik, Ewa; Kaczmarska, Karolina

    2015-01-25

    FT-IR and FT-Raman spectroscopic methods allowed to identify the cross-linking process of the aqueous composition of poly(acrylic acid)/sodium salt of carboxymethyl starch (PAA/CMS-Na) applied as a binder for moulding sands. The cross-linking was performed by chemical methods by introducing cross-linking substances with Ca(2+) ions or glutaraldehyde and by physical way, applying the microwave radiation. It was found that Ca(2+) ions cause formation of cross-linking ionic bonds within carboxyl and carboxylate groups. Glutaraldehyde generates formation of cross-linking bonds with hemiacetal and acetal structures. Whereas in the microwave radiation field, due to dehydration, lattices are formed by anhydride bonds.

  11. FT-IR and FT-Raman studies of cross-linking processes with Ca2+ ions, glutaraldehyde and microwave radiation for polymer composition of poly(acrylic acid)/sodium salt of carboxymethyl starch - Part I

    NASA Astrophysics Data System (ADS)

    Grabowska, Beata; Sitarz, Maciej; Olejnik, Ewa; Kaczmarska, Karolina

    2015-01-01

    FT-IR and FT-Raman spectroscopic methods allowed to identify the cross-linking process of the aqueous composition of poly(acrylic acid)/sodium salt of carboxymethyl starch (PAA/CMS-Na) applied as a binder for moulding sands. The cross-linking was performed by chemical methods by introducing cross-linking substances with Ca2+ ions or glutaraldehyde and by physical way, applying the microwave radiation. It was found that Ca2+ ions cause formation of cross-linking ionic bonds within carboxyl and carboxylate groups. Glutaraldehyde generates formation of cross-linking bonds with hemiacetal and acetal structures. Whereas in the microwave radiation field, due to dehydration, lattices are formed by anhydride bonds.

  12. Composition of dissolved organic nitrogen in continental precipitation investigated by ultra-high resolution FT-ICR mass spectrometry.

    PubMed

    Altieri, Katye E; Turpin, Barbara J; Seitzinger, Sybil P

    2009-09-15

    The atmospheric transport of fixed nitrogen (N) is a critical component of the global N cycle that has been heavily impacted by human activities. It has been shown that organic N is an important contributor to atmospheric N, but its sources and composition are largely unknown. Rainwater samples collected in New Jersey were analyzed by negative and positive ion ultrahigh-resolution electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Elemental compositions of 402 N-containing compounds were determined and five main groups of compound classes were identified: compounds containing carbon, hydrogen, oxygen, and N detected as positive ions (CHON+), compounds containing CHON detected as negative ions (CHON-), compounds containing CHN detected as positive ions (CHN+), and CHON compounds that contain sulfur (S) detected as both positive and negative ions (CHONS+, CHONS-, respectively). The CHON+ compound class has the largest number of compounds detected (i.e., 281), with the majority, i.e., 207, containing only one N atom. The elemental ratios of these compounds and their detection in the positive ion mode suggest that they are compounds with reduced N functionality. Known contributors to secondary organic aerosol with anthropogenic sources were also identified including organonitrate compounds and nitrooxy organosulfates.

  13. Fractionation process for petroleum wax

    SciTech Connect

    Jones, R.L.; Mitchael, M.R.; Krenowicz, R.A.; Southard, W.M.

    1991-07-16

    This patent describes a process which comprises separating a petroleum wax into a lower boiling wax fraction of a narrow melting range and a higher boiling wax fraction of wider melting range by subjecting the petroleum wax to distillation in a wiped film evaporator.

  14. Composition of suberin-associated waxes from the subterranean storage organs of seven plants : Parsnip, carrot, rutabaga, turnip, red beet, sweet potato and potato.

    PubMed

    Espelie, K E; Sadek, N Z; Kolattukudy, P E

    1980-10-01

    The waxes associated with the suberin in the periderm of the underground storage organs of parsnip (Pastinaca sativa L.), carrot (Daucus carota L.), rutabaga (Brassica napobrassica Mill.), turnip (Brassica rapa L.), red beet (Beta vulgaris L.), sweet potato (Ipomoea batatas L.) and potato (Solanum tuberosum L.) were isolated, fractionated into hydrocarbon, wax ester, free fatty alcohol and free fatty acid fractions, and analyzed by combined gas chromatography and mass spectrometry. The amount of wax extracted from the periderm of the storage organs ranged from 2 to 32 μg/cm(2). The hydrocarbons from the suberin layer have a broader chain-length distribution, a predominance of shorter carbon chains, and a higher proportion of even-numbered carbon chains than the leaf alkanes from the same plants. The major components of the free and esterified fatty alcohols and fatty acids have an even number of carbon atoms, and are similar in chain-length distribution to their counterparts found covalently attached to the suberin polymers; however, these suberin components are shorter in chain length than their cuticular analogues from the leaves. Also extracted from the storage organs were polar components which included fatty alcohols and fatty acids in a conjugated form, and ω-hydroxy acids and dicarboxylic acids. Evidence is presented that removal of the wax from the periderm of whole storage organs results in a decrease in diffusion resistance to moisture.

  15. Evaluation of FT-IR and Nile Red methods for microalgal lipid characterization and biomass composition determination.

    PubMed

    Feng, Guo-Dong; Zhang, Fang; Cheng, Li-Hua; Xu, Xin-Hua; Zhang, Lin; Chen, Huan-Lin

    2013-01-01

    To characterize lipid content of microalgal cells rapidly and accurately, the gravimetric determination, FT-IR and Nile Red (NR) staining were investigated on six typical eukaryotic and prokaryotic algae species. FT-IR and Nile Red were relative quantification methods and a standard curve was required in contrast to the gravimetric method. The FT-IR method determined the lipid, carbohydrate and protein contents simultaneously assuming that the algal cells only consisted of those three components. The Nile Red method was a relatively rapid method for neutral lipid content characterization by spectrofluorometry and could locate lipid body of the algal cell by fluorescence microscopy. According to sample sources and processing purposes, the gravimetric determination was preferable for large-scale cultivation with low-frequency monitoring, while FT-IR and Nile Red were suitable for general laboratory cultivation with medium-frequency monitoring, in particularly Nile Red was appropriate for small samples when high-frequency screening was required. PMID:23196229

  16. Hot Oil Removes Wax

    NASA Technical Reports Server (NTRS)

    Herzstock, James J.

    1991-01-01

    Mineral oil heated to temperature of 250 degrees F (121 degrees C) found effective in removing wax from workpieces after fabrication. Depending upon size and shape of part to be cleaned of wax, part immersed in tank of hot oil, and/or interior of part flushed with hot oil. Pump, fittings, and ancillary tooling built easily for this purpose. After cleaning, innocuous oil residue washed off part by alkaline aqueous degreasing process. Serves as relatively safe alternative to carcinogenic and environmentally hazardous solvent perchloroethylene.

  17. Reclaiming wax contaminated lubricating oils

    SciTech Connect

    Cleveland, R. T.; Silk, M. R.

    1981-05-26

    Dewaxed lube base stock oil which forms a wax haze on storage at a temperature above its cloud point is treated by contacting the oil and hydrogen with a zeolite catalyst such as zsm-5 to eliminate the wax-haze formation. The method may be used to reclaim wax-contaminated lube base stock oils and other waxcontaminated hydrocarbon oils.

  18. Combining FT-IR spectroscopy and multivariate analysis for qualitative and quantitative analysis of the cell wall composition changes during apples development.

    PubMed

    Szymanska-Chargot, M; Chylinska, M; Kruk, B; Zdunek, A

    2015-01-22

    The aim of this work was to quantitatively and qualitatively determine the composition of the cell wall material from apples during development by means of Fourier transform infrared (FT-IR) spectroscopy. The FT-IR region of 1500-800 cm(-1), containing characteristic bands for galacturonic acid, hemicellulose and cellulose, was examined using principal component analysis (PCA), k-means clustering and partial least squares (PLS). The samples were differentiated by development stage and cultivar using PCA and k-means clustering. PLS calibration models for galacturonic acid, hemicellulose and cellulose content from FT-IR spectra were developed and validated with the reference data. PLS models were tested using the root-mean-square errors of cross-validation for contents of galacturonic acid, hemicellulose and cellulose which was 8.30 mg/g, 4.08% and 1.74%, respectively. It was proven that FT-IR spectroscopy combined with chemometric methods has potential for fast and reliable determination of the main constituents of fruit cell walls.

  19. SEPARATION OF FISCHER-TROPSCH WAX FROM CATALYST BY SUPERCRITICAL EXTRACTION

    SciTech Connect

    MARK C. THIES; PATRICK C. JOYCE

    1998-10-31

    The objective of this research project is to evaluate the potential of supercritical fluid (SCF) extraction for the recovery and fractionation of the wax product from the slurry bubble column (SBC) reactor of the Fischer-Tropsch (F-T) process. The wax, comprised mostly of branched and linear alkanes with a broad molecular weight distribution up to C{sub 100}, will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300 C. Initial work is being performed using n-hexane as the solvent. The success of the project depends on two factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, this must be accomplished at conditions that do not entrain the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds. That is, a constant carbon-number distribution in the wax slurry must be maintained at steady-state column operation. Three major tasks are being undertaken to evaluate our proposed SCF extraction process. Task 1: Equilibrium solubility measurements for model F-T wax components in supercritical fluids at conditions representative of those in a SBC reactor. Task 2: Thermodynamic modeling of the measured VLE data for extending our results to real wax systems. Task 3: Process design studies of our proposed process. Additional details of the task structure are given.

  20. SEPARATION OF FISCHER-TROPSCH WAX FROM CATALYST BY SUPERCRITICAL EXTRACTION

    SciTech Connect

    MARK C. THIES; PATRICK C. JOYCE

    1998-07-31

    The objective of this research project is to evaluate the potential of supercritical fluid (SCF) extraction for the recovery and fractionation of the wax product from the slurry bubble column (SBC) reactor of the Fischer-Tropsch (F-T) process. The wax, comprised mostly of branched and linear alkanes with a broad molecular weight distribution up to C{sub 100}, will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300 C. Initial work is being performed using n-hexane as the solvent. The success of the project depends on two factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, this must be accomplished at conditions that do not entrain the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds. That is, a constant carbon-number distribution in the wax slurry must be maintained at steady-state column operation. Three major tasks are being undertaken to evaluate our proposed SCF extraction process. Task 1: Equilibrium solubility measurements for model F-T wax components in supercritical fluids at conditions representative of those in a SBC reactor. Task 2: Thermodynamic modeling of the measured VLE data for extending our results to real wax systems. Task 3: Process design studies of our proposed process. Additional details of the task structure are given.

  1. [Bee, wax and honey].

    PubMed

    de Laguérenne, Claude

    2003-01-01

    The archives of Nantes contain two manuscripts of the XVIIth century from which we found 63 formulae which enter bees, honey and wax. Our study concerns these various galeniques forms for internal use or external used in therapeutics and in beauty care.

  2. Wax ester profiling of seed oil by nano-electrospray ionization tandem mass spectrometry

    PubMed Central

    2013-01-01

    Background Wax esters are highly hydrophobic neutral lipids that are major constituents of the cutin and suberin layer. Moreover they have favorable properties as a commodity for industrial applications. Through transgenic expression of wax ester biosynthetic genes in oilseed crops, it is possible to achieve high level accumulation of defined wax ester compositions within the seed oil to provide a sustainable source for such high value lipids. The fatty alcohol moiety of the wax esters is formed from plant-endogenous acyl-CoAs by the action of fatty acyl reductases (FAR). In a second step the fatty alcohol is condensed with acyl-CoA by a wax synthase (WS) to form a wax ester. In order to evaluate the specificity of wax ester biosynthesis, analytical methods are needed that provide detailed wax ester profiles from complex lipid extracts. Results We present a direct infusion ESI-tandem MS method that allows the semi-quantitative determination of wax ester compositions from complex lipid mixtures covering 784 even chain molecular species. The definition of calibration prototype groups that combine wax esters according to their fragmentation behavior enables fast quantitative analysis by applying multiple reaction monitoring. This provides a tool to analyze wax layer composition or determine whether seeds accumulate a desired wax ester profile. Besides the profiling method, we provide general information on wax ester analysis by the systematic definition of wax ester prototypes according to their collision-induced dissociation spectra. We applied the developed method for wax ester profiling of the well characterized jojoba seed oil and compared the profile with wax ester-accumulating Arabidopsis thaliana expressing the wax ester biosynthetic genes MaFAR and ScWS. Conclusions We developed a fast profiling method for wax ester analysis on the molecular species level. This method is suitable to screen large numbers of transgenic plants as well as other wax ester samples

  3. Keeping Wax Liquid For Application

    NASA Technical Reports Server (NTRS)

    Meyer, Russell V.

    1989-01-01

    "Hot gun" applies masking wax and similar materials in liquid state. Holding chamber and nozzle supply continuous heat to wax, and wax injects directly into hole as liquid. Nozzles of various sizes interchange so one selects nozzle having opening suited to viscosity of wax and size of hole in particular application. Gun fast, eliminates repeated application, and greatly reduces cleanup time. Available commercially for applying hot glue, used to ensure wax penetrates and fills holes, flow passages, and manifold passages so contamination sealed off during manufacturing operations.

  4. Mammalian Wax Biosynthesis

    PubMed Central

    Cheng, Jeffrey B.; Russell, David W.

    2009-01-01

    The conversion of fatty acids to fatty alcohols is required for the synthesis of wax monoesters and ether lipids. The mammalian enzymes that synthesize fatty alcohols have not been identified. Here, an in silico approach was used to discern two putative reductase enzymes designated FAR1 and FAR2. Expression studies in intact cells showed that FAR1 and FAR2 cDNAs encoded isozymes that reduced fatty acids to fatty alcohols. Fatty acyl-CoA esters were the substrate of FAR1, and the enzyme required NADPH as a cofactor. FAR1 preferred saturated and unsaturated fatty acids of 16 or 18 carbons as substrates, whereas FAR2 preferred saturated fatty acids of 16 or 18 carbons. Confocal light microscopy indicated that FAR1 and FAR2 were localized in the peroxisome. The FAR1 mRNA was detected in many mouse tissues with the highest level found in the preputial gland, a modified sebaceous gland. The FAR2 mRNA was more restricted in distribution and most abundant in the eyelid, which contains wax-laden meibomian glands. Both FAR mRNAs were present in the brain, a tissue rich in ether lipids. The data suggest that fatty alcohol synthesis in mammals is accomplished by two fatty acyl-CoA reductase isozymes that are expressed at high levels in tissues known to synthesize wax monoesters and ether lipids. PMID:15220348

  5. Organogel formation of soybean oil with waxes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many waxes including plant waxes and animal waxes were evaluated for the gelation ability toward soybean oil (SBO) and compared with hydrogenated vegetable oils, petroleum waxes and commercial non-edible gelling agents to understand factors affecting the gelation ability of a gelator. Sunflower wax...

  6. 21 CFR 178.3850 - Reinforced wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Reinforced wax. 178.3850 Section 178.3850 Food and... and Production Aids § 178.3850 Reinforced wax. Reinforced wax may be safely used as an article or... holding food subject to the provisions of this section. (a) Reinforced wax consists of petroleum wax...

  7. Plant surface wax affects parasitoid's response to host footprints

    NASA Astrophysics Data System (ADS)

    Rostás, Michael; Ruf, Daniel; Zabka, Vanessa; Hildebrandt, Ulrich

    2008-10-01

    The plant surface is the substrate upon which herbivorous insects and natural enemies meet and thus represents the stage for interactions between the three trophic levels. Plant surfaces are covered by an epicuticular wax layer which is highly variable depending on species, cultivar or plant part. Differences in wax chemistry may modulate ecological interactions. We explored whether caterpillars of Spodoptera frugiperda, when walking over a plant surface, leave a chemical trail (kairomones) that can be detected by the parasitoid Cotesia marginiventris. Chemistry and micromorphology of cuticular waxes of two barley eceriferum wax mutants ( cer-za.126, cer-yp.949) and wild-type cv. Bonus (wt) were assessed. The plants were then used to investigate potential surface effects on the detectability of caterpillar kairomones. Here we provide evidence that C. marginiventris responds to chemical footprints of its host. Parasitoids were able to detect the kairomone on wild-type plants and on both cer mutants but the response to cer-yp.949 (reduced wax, high aldehyde fraction) was less pronounced. Experiments with caterpillar-treated wt and mutant leaves offered simultaneously, confirmed this observation: no difference in wasp response was found when wt was tested against cer-za.126 (reduced wax, wt-like chemical composition) but wt was significantly more attractive than cer-yp.949. This demonstrates for the first time that the wax layer can modulate the detectability of host kairomones.

  8. Supercritical phase process for selective synthesis of wax from syngas

    SciTech Connect

    Fan, Li; Yoshii, Kyotaka; Yan, Shi-Run

    1996-10-01

    Wax is widely used in many fields. Much attention was focused on its production method for its increasingly high price. It is difficult to selectively synthesize wax from syngas through Fischer-Tropsch reaction, due to ASF regulation. Here we report that addition of several percent of heavy {alpha}-olefins (i.e. C{sub 7}-C{sub 17}), which are of low value, into supercritical phase F-T reactions can accelerate carbon chain growth remarkably. Wax yield was enhanced twice or three times in olefin-added case, where high cobalt-content catalysts was employed. More interestingly, CO conversion and CO{sub 2} CH{sub 4} selectively decreased if heavy olefin was added. It should be stressed that this effect can not appear in gas-phase F-T reaction and is not so obvious in liquid-phase F-T reaction. Influence of catalysts pore size, type and amount of added olefins; was also investigated. Using the same high cobalt-ontent catalysts, CO/CO{sub 2} mixture gas diluted with much nitrogen reacted with hydrogen completely to form liquid hydrocarbons effectively.

  9. Phosphorescent compositions, methods of making the compositions, and methods of using the compositions

    SciTech Connect

    Jia, Weiyi; Wang, Xiaojun; Jia, George D.; Lewis, Linda; Yen, Laurel C.

    2014-06-24

    Compositions, methods of making compositions, materials including compositions, crayons including compositions, paint including compositions, ink including compositions, waxes including compositions, polymers including compositions, vesicles including the compositions, methods of making each, and the like are disclosed.

  10. Phosphorescent compositions, methods of making the compositions, and methods of using the compositions

    SciTech Connect

    Jia, Weiyi; Wang, Xiaojun; Yen, William; Yen, Laurel C.; Jia, George D.

    2012-12-04

    Compositions, methods of making compositions, materials including compositions, crayons including compositions, paint including compositions, ink including compositions, waxes including compositions, polymers including compositions, vesicles including the compositions, methods of making each, and the like are disclosed.

  11. Separation of fischer-Tropsch Wax from Catalyst by Supercritical Extraction.

    SciTech Connect

    Joyce, P.C.; Thies, M.C.; Sherrard, D.; Biales, J.; Kilpatrick, P.; Roberts, G.

    1997-07-31

    Although alkanes are the major constituent of a Fischer-Tropsch wax, significant quantities (e.g., up to 30 wt %) of long-chain alcohol and alkene compounds can also be found in a F-T wax. With the lack of experimental data, the effect that the hydroxy and double-bond functional groups have on the phase behavior of systems containing long- chain hydrocarbons is unknown. Therefore, the phase behavior of the system n-hexane/1-hexadecanol was measured for comparison with the previously measured system n-hexane/hexadecane. Vapor and liquid equilibrium compositions and mixture critical points were measured at 198.9, 251.3, 299.2, and 349.9 {degrees}C at pressures ranging from 6.2 to 46.4 bar. Temperature and pressure measurements for all isotherms are believed to be accurate to better than plus or minus 3 and 4 percent, respectively. Results indicate that the addition of the alcohol group to a C 16 hydrocarbon chain significantly affects the phase behavior with hexane, with the two-phase region extending to significantly higher (i.e., up to about 10 bar higher) pressures. The presence of an alcohol group was also found to be an impediment to obtaining a good fit of the experimental data with the Peng-Robinson equation.

  12. New way to characterize the percolation threshold of polyethylene and carbon nanotube polymer composites using Fourier transform (FT) rheology

    NASA Astrophysics Data System (ADS)

    Ahirwal, Deepak; Palza, Humberto; Schlatter, Guy; Wilhelm, Manfred

    2014-08-01

    In this article, a new way to characterize the percolation threshold of polymer nanocomposites made of polyethylene (PE) with single and multi walled carbon nanotubes (SWCNTs and MWCNTs) is presented. Small and large oscillatory shear (SAOS and LAOS) experiments were performed to characterize the degree of dispersion and percolation threshold. The analysis of the stress response in the LAOS regime as a function of the applied deformation amplitude and frequency was performed using Fourier Transform (FT)-Rheology. The zero strain intrinsic nonlinear parameter, Q0(ω), was calculated by extrapolation of I3/1(γ0, ω) and was, used to quantify the nonlinearity measured by FT-Rheology. Interestingly, a drop in Q0 as a function of the CNT weight fraction at a fixed frequency was found that was below the percolation threshold. This was followed by, a steep rise in Q0 above the percolation threshold. Therefore, the new method based on this observation that is proposed and described with this article has the potential to lead to a better understanding of structure-property relationships in polymer nanocomposites.

  13. A 25,000-year record of climate-induced changes in lowland vegetation of eastern equatorial Africa revealed by the stable carbon-isotopic composition of fossil plant leaf waxes

    NASA Astrophysics Data System (ADS)

    Sinninghe Damsté, Jaap S.; Verschuren, Dirk; Ossebaar, Jort; Blokker, Jord; van Houten, Rianne; van der Meer, Marcel T. J.; Plessen, Birgit; Schouten, Stefan

    2011-02-01

    The debate of climate versus CO2 in controlling the long-term dynamics of tropical African vegetation has focused on events at the upper tree-line, since the relevant paleodata tend to be from mid-elevation sites (~ 2000-3000 m). Less well known is the relative importance of CO2 in regulating the dynamics of tropical lowland (< 1500 m) vegetation, particularly that of the dry open woodlands, bush- and grasslands covering much of eastern equatorial Africa. Here we examine the stable carbon isotopic composition of n-alkanes in the sediment record of Lake Challa, a lowland crater lake near Mt. Kilimanjaro, covering the last 25,000 years. The distributions of the n-alkanes, with dominance of the long-chain odd-carbon-numbered components, and their isotopic composition reveal a mixed origin. The C23 and C25n-alkanes are depleted in 13C, with δ13C values between - 30 and - 50‰. In shallow lakes these n-alkanes are thought to derive from non-emergent aquatic plants, but this is unlikely in this steep-sided crater lake as it lacks a significant littoral habitat. The C27+n-alkanes are predominantly derived from leaf wax lipids of terrestrial plants, brought into the lake predominantly by local soil run-off. Their δ13C values, in particular that of the n-C31 alkane, reveal a marked transition in local lowland vegetation from being dominated (~ 70-100%) by C4 plants during the glacial period until 16.5 cal kyr BP, to a more mixed C3/C4 composition (~ 30-60% C4) during the Holocene. The start of the late-glacial trend towards a greater proportion of C3 plants coincided with the start of increasing monsoon rainfall, ~ 1500 years after the onset of the rise in atmospheric CO2 and ~ 3500 years after the onset of post-glacial warming. The transition was interrupted during the dry Younger Dryas period (13.0-11.7 cal kyr BP), when C4 plants again became much more prevalent, almost reaching their glacial-period abundance. Notably, the principal trend in leaf-wax δ13C values

  14. The development of a method of producing etch resistant wax patterns on solar cells

    NASA Technical Reports Server (NTRS)

    Pastirik, E.

    1980-01-01

    A potentially attractive technique for wax masking of solar cells prior to etching processes was studied. This technique made use of a reuseable wax composition which was applied to the solar cell in patterned form by means of a letterpress printing method. After standard wet etching was performed, wax removal by means of hot water was investigated. Application of the letterpress wax printing process to silicon was met with a number of difficulties. The most serious shortcoming of the process was its inability to produce consistently well-defined printed patterns on the hard silicon cell surface.

  15. Comparative Evaluation of Rice Bran Wax as an Ointment Base with Standard Base

    PubMed Central

    Sabale, Vidya; Sabale, P. M.; Lakhotiya, C. L.

    2009-01-01

    Waxes have been used in many cosmetic preparations and pharmaceuticals as formulation aids. Rice bran wax is a byproduct of rice bran oil industry. Present investigation has been aimed to explore the possible utility of rice bran wax as ointment base compared to standard base. The rice bran wax obtained, purified and its physicochemical characteristics were determined. Ointment base acts as a carrier for medicaments. The ointment base composition determines not only the extent of penetration but also controls the transfer of medicaments from the base to the body tissues. Rice bran wax base was compared with standard base for appearance, spreadability, water number, wash ability and diffusibility. The results show that rice bran wax acts as an ointment base as far as its pharmaceutical properties are concerned and it could effectively replace comparatively costlier available ointment bases. PMID:20177466

  16. Wax and hydrate control with electrical power

    SciTech Connect

    1997-08-01

    Electrical heating of subsea flowlines is an effective way to prevent wax and hydrate information, especially for long transportation distances and in low-temperature deep water. Systems are available for use in conjunction with bundles, pipe-in-pipe, and wet-thermal-insulation systems. These systems provide environmentally friendly fluid-temperature control without chemicals or flaring for pipeline depressurizing. Enhanced production is achieved because no time is lost by unnecessary depressurizing, pigging, heating-medium circulation, or removal of hydrate and wax blockages. The seabed temperature at 100-m and greater water depths may range from 7 to {minus}1.5 C, causing a rapid cooling of the hot well streams being transported in subsea flowlines. Under these supercooling conditions, vulnerable crude oils and multiphase compositions will deposit wax and asphalts; also the gas/water phase may freeze solid with hydrate particles. The paper discusses thermal-insulated flowlines, heat-loss compensation with electrical power, electrical power consumption and operation, and subsea electrical-power distribution system.

  17. Wax layers on Cosmos bipinnatus petals contribute unequally to total petal water resistance.

    PubMed

    Buschhaus, Christopher; Hager, Dana; Jetter, Reinhard

    2015-01-01

    Cuticular waxes coat all primary aboveground plant organs as a crucial adaptation to life on land. Accordingly, the properties of waxes have been studied in much detail, albeit with a strong focus on leaf and fruit waxes. Flowers have life histories and functions largely different from those of other organs, and it remains to be seen whether flower waxes have compositions and physiological properties differing from those on other organs. This work provides a detailed characterization of the petal waxes, using Cosmos bipinnatus as a model, and compares them with leaf and stem waxes. The abaxial petal surface is relatively flat, whereas the adaxial side consists of conical epidermis cells, rendering it approximately 3.8 times larger than the projected petal area. The petal wax was found to contain unusually high concentrations of C(22) and C(24) fatty acids and primary alcohols, much shorter than those in leaf and stem waxes. Detailed analyses revealed distinct differences between waxes on the adaxial and abaxial petal sides and between epicuticular and intracuticular waxes. Transpiration resistances equaled 3 × 10(4) and 1.5 × 10(4) s m(-1) for the adaxial and abaxial surfaces, respectively. Petal surfaces of C. bipinnatus thus impose relatively weak water transport barriers compared with typical leaf cuticles. Approximately two-thirds of the abaxial surface water barrier was found to reside in the epicuticular wax layer of the petal and only one-third in the intracuticular wax. Altogether, the flower waxes of this species had properties greatly differing from those on vegetative organs.

  18. 21 CFR 178.3710 - Petroleum wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Petroleum wax. 178.3710 Section 178.3710 Food and... and Production Aids § 178.3710 Petroleum wax. Petroleum wax may be safely used as a component of nonfood articles in contact with food, in accordance with the following conditions: (a) Petroleum wax is...

  19. 21 CFR 178.3710 - Petroleum wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Petroleum wax. 178.3710 Section 178.3710 Food and... and Production Aids § 178.3710 Petroleum wax. Petroleum wax may be safely used as a component of nonfood articles in contact with food, in accordance with the following conditions: (a) Petroleum wax is...

  20. 21 CFR 178.3710 - Petroleum wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Petroleum wax. 178.3710 Section 178.3710 Food and... and Production Aids § 178.3710 Petroleum wax. Petroleum wax may be safely used as a component of nonfood articles in contact with food, in accordance with the following conditions: (a) Petroleum wax is...

  1. 21 CFR 178.3710 - Petroleum wax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Petroleum wax. 178.3710 Section 178.3710 Food and... Petroleum wax. Petroleum wax may be safely used as a component of nonfood articles in contact with food, in accordance with the following conditions: (a) Petroleum wax is a mixture of solid hydrocarbons, paraffinic...

  2. Inhibiting wax deposition from a wax-containing oil

    SciTech Connect

    Zilch, H.E.

    1990-03-06

    This patent describes a method for inhibiting was deposition in an oil well producing a wax-containing oil. It comprises: injecting down-hole into the oil-pool at the base of the well a wax-inhibiting amount of a copolymer of between about 62 and about 66 weight percent ethylene and about 34 and about 38 weight percent vinyl acetate, aid copolymer having an average molecular weight below about 35,000.

  3. Detection of castor allergens in castor wax.

    PubMed

    Lehrer, S B; Karr, R M; Müller, D J; Salvaggio, J E

    1980-01-01

    The presence of castor bean allergens in castor wax products was determined by in vivo and in vitro analysis of castor wax extracts. Allergens were detected in one extract of castor wax by the PCA reaction in mice, the RAST inhibition reaction, and skin prick test in castor bean sensitive individuals. However, these allergens in the wax were of much lower potency than those in the bean, and were not detectable in a deodorant product utilizing castor wax.

  4. The crystal structure of waxes.

    PubMed

    Dorset, D L

    1995-12-01

    Quantitative electron crystallographic studies have been carried out on epitaxially oriented multi-component waxes. Intensities from two paraffin-based samples, an artificial six-component medium wax (equimolar distribution of chain lengths) and a petroleum-based wax (Gaussian distribution of chain lengths) have been used to determine their crystal structures. As found earlier for binary paraffin solid solutions, differences in molecular volume are compensated by longitudinal molecular shifts within individual lamellae. Nevertheless, each lamellar surface must remain flat enough, and with enough crystallographic order intact, to nucleate the next lamella, thus accounting for the observed long-range correlation in these crystals. Recrystallized beeswax also has a layer packing somewhat similar to the paraffin waxes. However, in this case, the lamellar order is 'frustrated' so that a certain amount of 'nematically' ordered material must be present, spanning the nascent lamellar interfaces. PMID:8554724

  5. Modeling of asphaltene and wax precipitation

    SciTech Connect

    Chung, F.; Sarathi, P.; Jones, R.

    1991-01-01

    This research project was designed to focus on the development of a predictive technique for organic deposition during gas injection for petroleum EOR. A thermodynamic model has been developed to describe the effects of temperature, pressure, and composition on asphaltene precipitation. The proposed model combines regular solution theory with Flory-Huggins polymer solutions theory to predict maximum volume fractions of asphaltene dissolved in oil. The model requires evaluation of vapor-liquid equilibria, first using an equation of state followed by calculations of asphaltene solubility in the liquid-phase. A state-of-the-art technique for C{sub 7+} fraction characterization was employed in developing this model. The preliminary model developed in this work was able to predict qualitatively the trends of the effects of temperature, pressure, and composition. Since the mechanism of paraffinic wax deposition is different from that of asphaltene deposition, another thermodynamic model based on the solid-liquid solution theory was developed to predict the wax formation. This model is simple and can predict the wax appearance temperature with reasonable accuracy. Accompanying the modeling work, experimental studies were conducted to investigate the solubility of asphaltene in oil land solvents and to examine the effects of oil composition, CO{sub 2}, and solvent on asphaltene precipitation and its properties. This research focused on the solubility reversibility of asphaltene in oil and the precipitation caused by CO{sub 2} injection at simulated reservoir temperature and pressure conditions. These experiments have provided many observations about the properties of asphaltenes for further improvement of the model, but more detailed information about the properties of asphaltenes in solution is needed for the development of more reliable asphaltene characterization techniques. 50 refs., 8 figs., 7 tabs.

  6. The wax glands and wax secretion of Matsucoccus matsumurae at different development stages.

    PubMed

    Xie, Yingping; Tian, Fen; Liu, Weimin; Zhang, Yanfeng; Xue, Jiaoliang; Zhao, Youyou; Wu, Jun

    2014-05-01

    In this paper, the wax secretions and wax glands of Matsucoccus matsumurae (Kuwana) at different instars were investigated using light microscopy, scanning electron microscopy and transmission electron microscopy. The first and second instar nymphs were found to secrete wax filaments via the wax glands located in the atrium of the abdominal spiracles, which have a center open and a series of outer ring pores. The wax gland of the abdominal spiracle possesses a large central wax reservoir and several wax-secreting cells. Third-instar male nymphs secreted long and translucent wax filaments from monolocular, biolocular, trilocular and quadrilocular pores to form twine into cocoons. The adult male secreted long and straight wax filaments in bundles from a group of 18-19 wax-secreting tubular ducts on the abdominal segment VII. Each tube duct contained five or six wax pores. The adult female has dorsal cicatrices distributed in rows, many biolocular tubular ducts and multilocular disc pores with 8-12 loculi secreting wax filaments that form the egg sac, and a rare type wax pores with 10 loculi secreting 10 straight, hollow wax filaments. The ultrastructure and cytological characteristics of the wax glands include wax-secreting cells with a large nucleus, multiple mitochondria and several rough endoplasmic reticulum. The functions of the wax glands and wax secretions are discussed.

  7. Chemical Composition and Potential Environmental Impacts of Water-Soluble Polar Crude Oil Components Inferred from ESI FT-ICR MS.

    PubMed

    Liu, Yina; Kujawinski, Elizabeth B

    2015-01-01

    Polar petroleum components enter marine environments through oil spills and natural seepages each year. Lately, they are receiving increased attention due to their potential toxicity to marine organisms and persistence in the environment. We conducted a laboratory experiment and employed state-of-the-art Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to characterize the polar petroleum components within two operationally-defined seawater fractions: the water-soluble fraction (WSF), which includes only water-soluble molecules, and the water-accommodated fraction (WAF), which includes WSF and microscopic oil droplets. Our results show that compounds with higher heteroatom (N, S, O) to carbon ratios (NSO:C) than the parent oil were selectively partitioned into seawater in both fractions, reflecting the influence of polarity on aqueous solubility. WAF and WSF were compositionally distinct, with unique distributions of compounds across a range of hydrophobicity. These compositional differences will likely result in disparate impacts on environmental health and organismal toxicity, and thus highlight the need to distinguish between these often-interchangeable terminologies in toxicology studies. We use an empirical model to estimate hydrophobicity character for individual molecules within these complex mixtures and provide an estimate of the potential environmental impacts of different crude oil components.

  8. Chemical Composition and Potential Environmental Impacts of Water-Soluble Polar Crude Oil Components Inferred from ESI FT-ICR MS

    PubMed Central

    Liu, Yina; Kujawinski, Elizabeth B.

    2015-01-01

    Polar petroleum components enter marine environments through oil spills and natural seepages each year. Lately, they are receiving increased attention due to their potential toxicity to marine organisms and persistence in the environment. We conducted a laboratory experiment and employed state-of-the-art Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to characterize the polar petroleum components within two operationally-defined seawater fractions: the water-soluble fraction (WSF), which includes only water-soluble molecules, and the water-accommodated fraction (WAF), which includes WSF and microscopic oil droplets. Our results show that compounds with higher heteroatom (N, S, O) to carbon ratios (NSO:C) than the parent oil were selectively partitioned into seawater in both fractions, reflecting the influence of polarity on aqueous solubility. WAF and WSF were compositionally distinct, with unique distributions of compounds across a range of hydrophobicity. These compositional differences will likely result in disparate impacts on environmental health and organismal toxicity, and thus highlight the need to distinguish between these often-interchangeable terminologies in toxicology studies. We use an empirical model to estimate hydrophobicity character for individual molecules within these complex mixtures and provide an estimate of the potential environmental impacts of different crude oil components. PMID:26327219

  9. Investigation of liquid wax components of Egyptian jojoba seeds.

    PubMed

    El-Mallah, Mohammed Hassan; El-Shami, Safinaz Mohammed

    2009-01-01

    Egyptian jojoba seeds newly cultivated in Ismailia desert in Egypt promoted us to determine its lipid components. Fatty alcohols, fatty acids, wax esters and sterols patterns were determined by capillary GLC whereas, tocopherols profile, isopropenoid alcohols and sterylglycosides were determined by HPLC. The Egyptian seeds are rich in wax esters (55 %) with fatty alcohols C20:1 and C22:1 as major components and amounted to 43.0 % and 45.6 % respectively followed by C24:1 and C18:1(9.6 % and 1.3 % respectively). The fatty acids profile showed that C20:1 is the major constituent (60 %) followed by C18:1 and C22:1 (14.5 and 11.8 % respectively) whereas C24:1 was present at low concentration amounted to 1.6 %. In addition, the Egyptian jojoba wax contained C18:2 fatty acid at a level of 8.7 %. Wax esters composition showed that the local wax had C42 and C40 esters as major components amounted to 51.1 and 30.1 % respectively. Also, it had C44 and C38 at reasonable amounts (10.0 and 6.3 % respectively). Whereas C36 and C46 were present at lower concentrations amounted to 1.4 and 1.1 respectively. The sterols analysis showed the presence of campe-, stigma-, beta-sito-, and isofuco- sterol amounting to 18.4 %, 6.9 %, 68.7 %, and 6.0 % respectively. The tocopherols pattern revealed that the local seed wax contained gamma-tocopherol as major constituent (79.2 %) followed by alpha-tocopherol (20.3 %). beta-tocopherol as well as delta-tocopherol were found as minor constituents. The isopropenoid alcohols and the sterylglycosides (free and acylated) were not detected. The wax is proposed to be used in oleo chemistry and cosmetics.

  10. Localization of the Transpiration Barrier in the Epi- and Intracuticular Waxes of Eight Plant Species: Water Transport Resistances Are Associated with Fatty Acyl Rather Than Alicyclic Components.

    PubMed

    Jetter, Reinhard; Riederer, Markus

    2016-02-01

    Plant cuticular waxes play a crucial role in limiting nonstomatal water loss. The goal of this study was to localize the transpiration barrier within the layered structure of cuticles of eight selected plant species and to put its physiological function into context with the chemical composition of the intracuticular and epicuticular wax layers. Four plant species (Tetrastigma voinierianum, Oreopanax guatemalensis, Monstera deliciosa, and Schefflera elegantissima) contained only very-long-chain fatty acid (VLCFA) derivatives such as alcohols, alkyl esters, aldehydes, and alkanes in their waxes. Even though the epicuticular and intracuticular waxes of these species had very similar compositions, only the intracuticular wax was important for the transpiration barrier. In contrast, four other species (Citrus aurantium, Euonymus japonica, Clusia flava, and Garcinia spicata) had waxes containing VLCFA derivatives, together with high percentages of alicyclic compounds (triterpenoids, steroids, or tocopherols) largely restricted to the intracuticular wax layer. In these species, both the epicuticular and intracuticular waxes contributed equally to the cuticular transpiration barrier. We conclude that the cuticular transpiration barrier is primarily formed by the intracuticular wax but that the epicuticular wax layer may also contribute to it, depending on species-specific cuticle composition. The barrier is associated mainly with VLCFA derivatives and less (if at all) with alicyclic wax constituents. The sealing properties of the epicuticular and intracuticular layers were not correlated with other characteristics, such as the absolute wax amounts and thicknesses of these layers.

  11. Predictable diastema reduction with filled resin: diagnostic wax-up.

    PubMed

    Newitter, D A

    1986-03-01

    A method for predictably altering anterior esthetics with composite resins is presented. The diagnostic wax-up is the key element. It is used to make a patient presentation cast and to customize resin forms. The resin forms are used to reproduce the predicted tooth form in the mouth quickly and accurately. The method should alert the dentist to the technical feasibility of the planned treatment and the difficulties that may be encountered. In addition, it should alleviate potential misunderstanding and disappointment of the patient. Finally, diagnostic waxing is time saving and simplifies the chairside procedure.

  12. [Analysis of constituents in urushi wax, a natural food additive].

    PubMed

    Jin, Zhe-Long; Tada, Atsuko; Sugimoto, Naoki; Sato, Kyoko; Masuda, Aino; Yamagata, Kazuo; Yamazaki, Takeshi; Tanamoto, Kenichi

    2006-08-01

    Urushi wax is a natural gum base used as a food additive. In order to evaluate the quality of urushi wax as a food additive and to obtain information useful for setting official standards, we investigated the constituents and their concentrations in urushi wax, using the same sample as scheduled for toxicity testing. After methanolysis of urushi wax, the composition of fatty acids was analyzed by GC/MS. The results indicated that the main fatty acids were palmitic acid, oleic acid and stearic acid. LC/MS analysis of urushi wax provided molecular-related ions of the main constituents. The main constituents were identified as triglycerides, namely glyceryl tripalmitate (30.7%), glyceryl dipalmitate monooleate (21.2%), glyceryl dioleate monopalmitate (2.1%), glyceryl monooleate monopalmitate monostearate (2.6%), glyceryl dipalmitate monostearate (5.6%), glyceryl distearate monopalmitate (1.4%). Glyceryl dipalmitate monooleate isomers differing in the binding sites of each constituent fatty acid could be separately determined by LC/MS/MS. PMID:16984037

  13. Solubility determination of TNT and wax and their fractionation from an explosive material using a supercritical fluid

    SciTech Connect

    Ashraf-Khorassani, M.; Taylor, L.T.

    1999-12-01

    The solubilities of 2,4,6-trinitrotoluene (TNT) and wax have been measured in supercritical carbon dioxide (Co{sub 2}) at three pressures and temperatures under static conditions. The concentrations of each component were determined off-line via ultraviolet (TNT) and evaporative light scattering (wax) detection. The solubility of TNT was an order of magnitude higher than that of wax. Gas chromatographic assay of the wax extract revealed that only the lower molecular weight components dissolved. Fractionation of the TNT and wax from an explosive material referred to as Composition B was attempted by making incremental increases in CO{sub 2} density. Composition B contains 59.5% cyclotrimethylene triamine (RDX), 39.5% TNT, and 1% wax. While TNT and Wax could be easily isolated from nitramine TDX, attempts to separate TNT from wax were not totally successful. More specifically, the initial fractions contained the lower molecular weight wax components in addition to major amounts of TNT. Since the percentage of TNT was approximately 50 times the amount of wax, later fractions were 100% TNT although most of the TNT was removed at the lower densities.

  14. Comb-wax discrimination by honeybees tested with the proboscis extension reflex.

    PubMed

    Fröhlich, B; Riederer, M; Tautz, J

    2000-05-01

    We used the proboscis extension reflex of honeybees to test their ability to discriminate between comb waxes of different ages (wax scales, 1-week-old wax, 2- to 3-year-old wax, 8- to 10-year-old wax). Such waxes differ in their chemical composition, and an ability to discriminate between them may aid the orientation of the bees in the nest. To train the bees, we used whole extracts of waxes and four different fractions of the whole extract based on different elutions of solid-phase extractions (extract I, fraction A eluted with hexane and fraction B with diethylether; extract II, fraction B further subdivided into fraction C by elution with isopropylchloride and fraction D by elution with diethylether). In a differential training regime (six learning and six test trials) with whole extracts or with the different fractions, we paired one type of wax with a reward and another with no reward. The bees learned to discriminate between all tested pairs of whole extracts. The two subfractions (fractions A and B) gave different results: the bees could discriminate between waxes of different ages when fraction B was used but not when fraction A was used. A further subdivision of fraction B into fractions C and D showed that only fraction D contained the elements that enabled bees to discriminate between old and new wax. Fraction D makes up only 5?8 % of the total wax mass and contains hydroxy alkyl esters (5?6 % of the total wax mass), primary alcohols (0.3?0.5 % of the total wax mass) and acids (0.06?1. 0 % of the total wax mass). Fractions A and C (together forming 62?64 % of the total wax mass), which consist of unbranched and branched aliphatic hydrocarbons and alkyl esters, could not be discriminated by the bees. The remaining wax mass (25?29 %) was eluted with a mixture of chloroform, methanol and water (13:5:1) as fraction E.

  15. Evaluation of Wax Deposition and Its Control During Production of Alaska North Slope Oils

    SciTech Connect

    Tao Zhu; Jack A. Walker; J. Liang

    2008-12-31

    Due to increasing oil demand, oil companies are moving into arctic environments and deep-water areas for oil production. In these regions of lower temperatures, wax deposits begin to form when the temperature in the wellbore falls below wax appearance temperature (WAT). This condition leads to reduced production rates and larger pressure drops. Wax problems in production wells are very costly due to production down time for removal of wax. Therefore, it is necessary to develop a solution to wax deposition. In order to develop a solution to wax deposition, it is essential to characterize the crude oil and study phase behavior properties. The main objective of this project was to characterize Alaskan North Slope crude oil and study the phase behavior, which was further used to develop a dynamic wax deposition model. This report summarizes the results of the various experimental studies. The subtasks completed during this study include measurement of density, molecular weight, viscosity, pour point, wax appearance temperature, wax content, rate of wax deposition using cold finger, compositional characterization of crude oil and wax obtained from wax content, gas-oil ratio, and phase behavior experiments including constant composition expansion and differential liberation. Also, included in this report is the development of a thermodynamic model to predict wax precipitation. From the experimental study of wax appearance temperature, it was found that wax can start to precipitate at temperatures as high as 40.6 C. The WAT obtained from cross-polar microscopy and viscometry was compared, and it was discovered that WAT from viscometry is overestimated. From the pour point experiment it was found that crude oil can cease to flow at a temperature of 12 C. From the experimental results of wax content, it is evident that the wax content in Alaskan North Slope crude oil can be as high as 28.57%. The highest gas-oil ratio for a live oil sample was observed to be 619.26 SCF

  16. On-line analysis of chemical composition using an FT-Raman spectrometer in the near-ir

    SciTech Connect

    Garrison, A.A.

    1992-08-01

    Newly commercialized Fourier transform Raman spectroscopic instrumentation provides a simpler alternative for vibrational spectroscopic analysis. Instrument vendors currently design for laboratory use, but there are many potential process applications of these stable, easy to use instruments. Raman spectroscopy is highly suited to analysis of aqueous samples. Near infrared excitation minimized fluorescence interference and allows for remote operation via fiber optic probes. The Department of Energy has funded research at the Measurement and Control Center to establish the utility of this method for on-line composition analysis in distillation columns. Laboratory evaluation and instrument employs an air-cooled laser and a thermoelectrically cooled detector. The device is mounted on a three by foot cart for convenient location in control rooms. Current fiber optic extension cables allow for analysis in a cell thirty five meters from the instrument. Application of the device to acid an recovery column at Tennessee Eastman Corporation in Kingsport, Tennessee will be discussed. Sensor placement is critical to optimal application of any on-line device. Potential energy savings and product throughput increase will be detailed. 2 refs.

  17. On-line analysis of chemical composition using an FT-Raman spectrometer in the near-ir

    SciTech Connect

    Garrison, A.A.

    1992-01-01

    Newly commercialized Fourier transform Raman spectroscopic instrumentation provides a simpler alternative for vibrational spectroscopic analysis. Instrument vendors currently design for laboratory use, but there are many potential process applications of these stable, easy to use instruments. Raman spectroscopy is highly suited to analysis of aqueous samples. Near infrared excitation minimized fluorescence interference and allows for remote operation via fiber optic probes. The Department of Energy has funded research at the Measurement and Control Center to establish the utility of this method for on-line composition analysis in distillation columns. Laboratory evaluation and instrument employs an air-cooled laser and a thermoelectrically cooled detector. The device is mounted on a three by foot cart for convenient location in control rooms. Current fiber optic extension cables allow for analysis in a cell thirty five meters from the instrument. Application of the device to acid an recovery column at Tennessee Eastman Corporation in Kingsport, Tennessee will be discussed. Sensor placement is critical to optimal application of any on-line device. Potential energy savings and product throughput increase will be detailed. 2 refs.

  18. 21 CFR 184.1978 - Carnauba wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... from the leaves and buds of the Brazilian wax palm Copernicia cerifera Martius. The wax is hard... fruits and fruit juices as defined in § 170.3(n)(35) of this chapter; and soft candy as defined in §...

  19. 21 CFR 184.1978 - Carnauba wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... from the leaves and buds of the Brazilian wax palm Copernicia cerifera Martius. The wax is hard... fruits and fruit juices as defined in § 170.3(n)(35) of this chapter; and soft candy as defined in §...

  20. 21 CFR 184.1978 - Carnauba wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... from the leaves and buds of the Brazilian wax palm Copernicia cerifera Martius. The wax is hard... fruits and fruit juices as defined in § 170.3(n)(35) of this chapter; and soft candy as defined in §...

  1. 21 CFR 184.1976 - Candelilla wax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... this chapter and in hard candy as defined in § 170.3(n)(25) of this chapter. (d) Prior sanctions for.... It is a hard, yellowish-brown, opaque-to-translucent wax. Candelilla wax is prepared by immersing...

  2. 21 CFR 184.1978 - Carnauba wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... from the leaves and buds of the Brazilian wax palm Copernicia cerifera Martius. The wax is hard... fruits and fruit juices as defined in § 170.3(n)(35) of this chapter; and soft candy as defined in §...

  3. 21 CFR 184.1978 - Carnauba wax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... the Brazilian wax palm Copernicia cerifera Martius. The wax is hard, brittle, sparingly soluble in... fruits and fruit juices as defined in § 170.3(n)(35) of this chapter; and soft candy as defined in §...

  4. Wax blockage in the ear (image)

    MedlinePlus

    The ear canal is lined with hair follicles and glands that produce a waxy oil called cerumen. Sometimes the ... wax than can be easily excreted out the ear. This extra wax may harden within the ear ...

  5. 21 CFR 178.3850 - Reinforced wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... holding food subject to the provisions of this section. (a) Reinforced wax consists of petroleum wax to... of substances Limitations Copolymer of isobutylene modified with isoprene Petroleum wax, Type I...

  6. 21 CFR 178.3850 - Reinforced wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... holding food subject to the provisions of this section. (a) Reinforced wax consists of petroleum wax to... of substances Limitations Copolymer of isobutylene modified with isoprene Petroleum wax, Type I...

  7. 21 CFR 178.3850 - Reinforced wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... holding food subject to the provisions of this section. (a) Reinforced wax consists of petroleum wax to... of substances Limitations Copolymer of isobutylene modified with isoprene Petroleum wax, Type I...

  8. 21 CFR 582.1978 - Carnauba wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Carnauba wax. 582.1978 Section 582.1978 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1978 Carnauba wax. (a) Product. Carnauba wax. (b) Conditions of use. This substance is...

  9. 21 CFR 582.1978 - Carnauba wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Carnauba wax. 582.1978 Section 582.1978 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1978 Carnauba wax. (a) Product. Carnauba wax. (b) Conditions of use. This substance is...

  10. 21 CFR 582.1978 - Carnauba wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Carnauba wax. 582.1978 Section 582.1978 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1978 Carnauba wax. (a) Product. Carnauba wax. (b) Conditions of use. This substance is...

  11. 21 CFR 582.1978 - Carnauba wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Carnauba wax. 582.1978 Section 582.1978 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1978 Carnauba wax. (a) Product. Carnauba wax. (b) Conditions of use. This substance is...

  12. Plant leaf wax biomarkers capture gradients in hydrogen isotopes of precipitation from the Andes and Amazon

    NASA Astrophysics Data System (ADS)

    Feakins, Sarah J.; Bentley, Lisa Patrick; Salinas, Norma; Shenkin, Alexander; Blonder, Benjamin; Goldsmith, Gregory R.; Ponton, Camilo; Arvin, Lindsay J.; Wu, Mong Sin; Peters, Tom; West, A. Joshua; Martin, Roberta E.; Enquist, Brian J.; Asner, Gregory P.; Malhi, Yadvinder

    2016-06-01

    Plant leaf waxes have been found to record the hydrogen isotopic composition of precipitation and are thus used to reconstruct past climate. To assess how faithfully they record hydrological signals, we characterize leaf wax hydrogen isotopic compositions in forest canopy trees across a highly biodiverse, 3 km elevation range on the eastern flank of the Andes. We sampled the dominant tree species and assessed their relative abundance in the tree community. For each tree we collected xylem and leaf samples for analysis of plant water and plant leaf wax hydrogen isotopic compositions. In total, 176 individuals were sampled across 32 species and 5 forest plots that span the gradient. We find both xylem water and leaf wax δD values of individuals correlate (R2 = 0.8 and R2 = 0.3 respectively) with the isotopic composition of precipitation (with an elevation gradient of -21‰ km-1). Minimal leaf water enrichment means that leaf waxes are straightforward recorders of the isotopic composition of precipitation in wet climates. For these tropical forests we find the average fractionation between source water and leaf wax for C29n-alkanes, -129 ± 2‰ (s.e.m., n = 136), to be indistinguishable from that of temperate moist forests. For C28n-alkanoic acids the average fractionation is -121 ± 3‰ (s.e.m., n = 102). Sampling guided by community assembly within forest plots shows that integrated plant leaf wax hydrogen isotopic compositions faithfully record the gradient of isotopes in precipitation with elevation (R2 = 0.97 for n-alkanes and 0.60 for n-alkanoic acids). This calibration study supports the use of leaf waxes as recorders of the isotopic composition of precipitation in lowland tropical rainforest, tropical montane cloud forests and their sedimentary archives.

  13. Structural features of reconstituted wheat wax films

    PubMed Central

    Pambou, Elias; Li, Zongyi; Campana, Mario; Hughes, Arwel; Clifton, Luke; Gutfreund, Philipp; Foundling, Jill

    2016-01-01

    Cuticular waxes are essential for the well-being of all plants, from controlling the transport of water and nutrients across the plant surface to protecting them against external environmental attacks. Despite their significance, our current understanding regarding the structure and function of the wax film is limited. In this work, we have formed representative reconstituted wax film models of controlled thicknesses that facilitated an ex vivo study of plant cuticular wax film properties by neutron reflection (NR). Triticum aestivum L. (wheat) waxes were extracted from two different wheat straw samples, using two distinct extraction methods. Waxes extracted from harvested field-grown wheat straw using supercritical CO2 are compared with waxes extracted from laboratory-grown wheat straw via wax dissolution by chloroform rinsing. Wax films were produced by spin-coating the two extracts onto silicon substrates. Atomic force microscopy and cryo-scanning electron microscopy imaging revealed that the two reconstituted wax film models are ultrathin and porous with characteristic nanoscale extrusions on the outer surface, mimicking the structure of epicuticular waxes found upon adaxial wheat leaf surfaces. On the basis of solid–liquid and solid–air NR and ellipsometric measurements, these wax films could be modelled into two representative layers, with the diffuse underlying layer fitted with thicknesses ranging from approximately 65 to 70 Å, whereas the surface extrusion region reached heights exceeding 200 Å. Moisture-controlled NR measurements indicated that water penetrated extensively into the wax films measured under saturated humidity and under water, causing them to hydrate and swell significantly. These studies have thus provided a useful structural basis that underlies the function of the epicuticular waxes in controlling the water transport of crops. PMID:27466439

  14. Structural features of reconstituted wheat wax films.

    PubMed

    Pambou, Elias; Li, Zongyi; Campana, Mario; Hughes, Arwel; Clifton, Luke; Gutfreund, Philipp; Foundling, Jill; Bell, Gordon; Lu, Jian R

    2016-07-01

    Cuticular waxes are essential for the well-being of all plants, from controlling the transport of water and nutrients across the plant surface to protecting them against external environmental attacks. Despite their significance, our current understanding regarding the structure and function of the wax film is limited. In this work, we have formed representative reconstituted wax film models of controlled thicknesses that facilitated an ex vivo study of plant cuticular wax film properties by neutron reflection (NR). Triticum aestivum L. (wheat) waxes were extracted from two different wheat straw samples, using two distinct extraction methods. Waxes extracted from harvested field-grown wheat straw using supercritical CO2 are compared with waxes extracted from laboratory-grown wheat straw via wax dissolution by chloroform rinsing. Wax films were produced by spin-coating the two extracts onto silicon substrates. Atomic force microscopy and cryo-scanning electron microscopy imaging revealed that the two reconstituted wax film models are ultrathin and porous with characteristic nanoscale extrusions on the outer surface, mimicking the structure of epicuticular waxes found upon adaxial wheat leaf surfaces. On the basis of solid-liquid and solid-air NR and ellipsometric measurements, these wax films could be modelled into two representative layers, with the diffuse underlying layer fitted with thicknesses ranging from approximately 65 to 70 Å, whereas the surface extrusion region reached heights exceeding 200 Å. Moisture-controlled NR measurements indicated that water penetrated extensively into the wax films measured under saturated humidity and under water, causing them to hydrate and swell significantly. These studies have thus provided a useful structural basis that underlies the function of the epicuticular waxes in controlling the water transport of crops. PMID:27466439

  15. Structural features of reconstituted wheat wax films.

    PubMed

    Pambou, Elias; Li, Zongyi; Campana, Mario; Hughes, Arwel; Clifton, Luke; Gutfreund, Philipp; Foundling, Jill; Bell, Gordon; Lu, Jian R

    2016-07-01

    Cuticular waxes are essential for the well-being of all plants, from controlling the transport of water and nutrients across the plant surface to protecting them against external environmental attacks. Despite their significance, our current understanding regarding the structure and function of the wax film is limited. In this work, we have formed representative reconstituted wax film models of controlled thicknesses that facilitated an ex vivo study of plant cuticular wax film properties by neutron reflection (NR). Triticum aestivum L. (wheat) waxes were extracted from two different wheat straw samples, using two distinct extraction methods. Waxes extracted from harvested field-grown wheat straw using supercritical CO2 are compared with waxes extracted from laboratory-grown wheat straw via wax dissolution by chloroform rinsing. Wax films were produced by spin-coating the two extracts onto silicon substrates. Atomic force microscopy and cryo-scanning electron microscopy imaging revealed that the two reconstituted wax film models are ultrathin and porous with characteristic nanoscale extrusions on the outer surface, mimicking the structure of epicuticular waxes found upon adaxial wheat leaf surfaces. On the basis of solid-liquid and solid-air NR and ellipsometric measurements, these wax films could be modelled into two representative layers, with the diffuse underlying layer fitted with thicknesses ranging from approximately 65 to 70 Å, whereas the surface extrusion region reached heights exceeding 200 Å. Moisture-controlled NR measurements indicated that water penetrated extensively into the wax films measured under saturated humidity and under water, causing them to hydrate and swell significantly. These studies have thus provided a useful structural basis that underlies the function of the epicuticular waxes in controlling the water transport of crops.

  16. Characterization of Glossy1-homologous genes in rice involved in leaf wax accumulation and drought resistance.

    PubMed

    Islam, Mohammad Asadul; Du, Hao; Ning, Jing; Ye, Haiyan; Xiong, Lizhong

    2009-07-01

    The outermost surfaces of plants are covered with an epicuticular wax layer that provides a primary waterproof barrier and protection against different environmental stresses. Glossy 1 (GL1) is one of the reported genes controlling wax synthesis. This study analyzed GL1-homologous genes in Oryza sativa and characterized the key members of this family involved in wax synthesis and stress resistance. Sequence analysis revealed 11 homologous genes of GL1 in rice, designated OsGL1-1 to OsGL1-11. OsGL1-1, -2 and -3 are closely related to GL1. OsGL1-4, -5, -6, and -7 are closely related to Arabidopsis CER1 that is involved in cuticular wax biosynthesis. OsGL1-8, -9, -10 and -11 are closely related to SUR2 encoding a putative sterol desaturase also involved in epicuticular wax biosynthesis. These genes showed variable expression levels in different tissues and organs of rice, and most of them were induced by abiotic stresses. Compared to the wild type, the OsGL1-2-over-expression rice exhibited more wax crystallization and a thicker epicuticular layer; while the mutant of this gene showed less wax crystallization and a thinner cuticular layer. Chlorophyll leaching experiment suggested that the cuticular permeability was decreased and increased in the over-expression lines and the mutant, respectively. Quantification analysis of wax composition by GC-MS revealed a significant reduction of total cuticular wax in the mutant and increase of total cuticular wax in the over-expression plants. Compared to the over-expression and wild type plants, the osgl1-2 mutant was more sensitive to drought stress at reproductive stage, suggesting an important role of this gene in drought resistance.

  17. Crude oil and fuel oil compositions

    SciTech Connect

    Tack, R.D.; Andrews, R.F.; Ayres, S.J.

    1989-10-17

    This patent describes a wax containing oil composition. It comprises crude oil or fuel oil and a wax crystal modifying amount of at least one polycarbonate having a number average molecular weight from about 300 to about 3000.

  18. Thermodynamics of wax precipitation in petroleum mixtures

    SciTech Connect

    Lira-Galeana, C.; Firoozabadi, A.; Prausnitz, J.M. |

    1996-01-01

    A thermodynamic framework is developed for calculating wax precipitation in petroleum mixtures over a wide temperature range. The framework uses the experimentally supported assumption that precipitated wax consists of several solid phases; each solid phase is described as a pure component or pseudocomponent that does not mix with other solid phases. Liquid-phase properties are obtained from an equation of state. Calculated wax-precipitation data are in excellent agreement with experimental results for binary and multicomponent hydrocarbon mixtures, including petroleum.

  19. Thermodynamics of wax precipitation in petroleum mixtures

    SciTech Connect

    Firoozabadi, A.; Lira-Galeana, C.L.; Prausnitz, J.M.

    1995-12-01

    A thermodynamic framework is developed for calculating wax precipitation in petroleum mixtures over a wide temperature range. The framework assumes that the precipitated wax consists of several solid phases; each solid-phase is described as a pure component or pseudocomponent which does not mix with other solid phases. Liquid-phase properties are obtained from an equation of state. Calculated wax precipitation data are in excellent agreement with experimental results for binary and multicomponent hydrocarbon mixtures, including petroleum.

  20. Verifying Dissolution Of Wax From Hardware Surfaces

    NASA Technical Reports Server (NTRS)

    Montoya, Benjamina G.

    1995-01-01

    Wax removed by cleaning solvent revealed by cooling solution with liquid nitrogen. Such improved procedure and test needed in case of hardware that must be protected by wax during machining or plating but required to be free of wax during subsequent use. Improved cleaning procedure and test take less than 5 minutes. Does not require special skill or equipment and performs at cleaning site. In addition, enables recovery of all cleaning solvent.

  1. Localization of the Transpiration Barrier in the Epi- and Intracuticular Waxes of Eight Plant Species: Water Transport Resistances Are Associated with Fatty Acyl Rather Than Alicyclic Components1[OPEN

    PubMed Central

    Jetter, Reinhard

    2016-01-01

    Plant cuticular waxes play a crucial role in limiting nonstomatal water loss. The goal of this study was to localize the transpiration barrier within the layered structure of cuticles of eight selected plant species and to put its physiological function into context with the chemical composition of the intracuticular and epicuticular wax layers. Four plant species (Tetrastigma voinierianum, Oreopanax guatemalensis, Monstera deliciosa, and Schefflera elegantissima) contained only very-long-chain fatty acid (VLCFA) derivatives such as alcohols, alkyl esters, aldehydes, and alkanes in their waxes. Even though the epicuticular and intracuticular waxes of these species had very similar compositions, only the intracuticular wax was important for the transpiration barrier. In contrast, four other species (Citrus aurantium, Euonymus japonica, Clusia flava, and Garcinia spicata) had waxes containing VLCFA derivatives, together with high percentages of alicyclic compounds (triterpenoids, steroids, or tocopherols) largely restricted to the intracuticular wax layer. In these species, both the epicuticular and intracuticular waxes contributed equally to the cuticular transpiration barrier. We conclude that the cuticular transpiration barrier is primarily formed by the intracuticular wax but that the epicuticular wax layer may also contribute to it, depending on species-specific cuticle composition. The barrier is associated mainly with VLCFA derivatives and less (if at all) with alicyclic wax constituents. The sealing properties of the epicuticular and intracuticular layers were not correlated with other characteristics, such as the absolute wax amounts and thicknesses of these layers. PMID:26644508

  2. Cuticular waxes in alpine meadow plants: climate effect inferred from latitude gradient in Qinghai-Tibetan Plateau.

    PubMed

    Guo, Yanjun; Guo, Na; He, Yuji; Gao, Jianhua

    2015-09-01

    Alpine meadow ecosystems are susceptible to climate changes. Still, climate impact on cuticular wax in alpine meadow plants is poorly understood. Assessing the variations of cuticular wax in alpine meadow plants across different latitudes might be useful for predicting how they may respond to climate change. We studied nine alpine meadows in a climate gradient in the east side of Qinghai-Tibetan Plateau, with mean annual temperature ranging from -7.7 to 3.2°C. In total, 42 plant species were analyzed for cuticular wax, averaged 16 plant species in each meadow. Only four plant species could be observed in all sampling meadows, including Kobresia humilis,Potentilla nivea,Anaphalis lacteal, and Leontopodium nanum. The amounts of wax compositions and total cuticular wax in the four plant species varied among sampling meadows, but no significant correlation could be observed between them and temperature, precipitation, and aridity index based on plant species level. To analyze the variations of cuticular wax on community level, we averaged the amounts of n-alkanes, aliphatic acids, primary alcohols, and total cuticular wax across all investigated plant species in each sampling site. The mean annual temperature, mean temperature in July, and aridity index were significantly correlated with the averaged amounts of wax compositions and total cuticular wax. The average chain length of n-alkanes in both plant and soil linearly increased with increased temperature, whereas reduced with increased aridity index. No significant correlation could be observed between mean annual precipitation and mean precipitation from June to August and the cuticular wax amounts and average chain length. Our results suggest that the survival of some alpine plants in specific environments might be depended on their abilities in adjusting wax deposition on plant leaves, and the alpine meadow plants as a whole respond to climate change, benefiting the stability of alpine meadow ecosystem.

  3. FT-IR and FT-Raman studies of cross-linking processes with Ca²⁺ ions, glutaraldehyde and microwave radiation for polymer composition of poly(acrylic acid)/sodium salt of carboxymethyl starch - In moulding sands, Part II.

    PubMed

    Grabowska, Beata; Sitarz, Maciej; Olejnik, Ewa; Kaczmarska, Karolina; Tyliszczak, Bozena

    2015-12-01

    The hardening process of moulding sands on quartz matrices bound by polymer binders containing carboxyl and hydroxyl groups can be carried out by using physical (microwave radiation, thermal holding) and chemical (Ca(2+) cations, glutaraldehyde) cross-linking agents. The highest hardening level obtain moulding sand samples containing binders in a form of the aqueous composition of poly(acrylic acid)/sodium salt of carboxymethyl starch (PAA/CMS-Na) within the microwave radiation field, for which the bending strength is of 1.6 MPa value even after 24h from ending the agent activity. The authors focused, in this study, on finding the reason of this effect. It was shown, by means of the FT-IR and FT-Raman spectroscopic methods, that the chemical adsorption process activated by microwaves plays an essential role. The applied microwaves activate the polar groups present in the polymer composition structure as well as the quartz crystals surfaces (silane groups). Then the chemical adsorption occurs in the binder-matrix system within the microwave radiation field and intermolecular lattices are formed with a participation of hydrogen bridges (SiOH⋯OC, SiOH⋯OH) and COSi type bonds. PMID:26125981

  4. Separation of Fischer-Tropsch wax from catalyst by supercritical extraction. Quarterly report, July 1, 1996 - September 30, 1996

    SciTech Connect

    Joyce, P.C.; Thies, M.C.; Sherrard, D.; Biales, J.; Kilpatrick, P.; Roberts, G.

    1996-12-31

    The objective of this research projects is to evaluate the potential of SCF extraction for separating the catalyst slurry of a Fischer- Tropsch (F-T) slurry bubble column (SBC) reactor into two fractions: (1) a catalyst-free wax containing less than 10 ppm particulate matter and (2) a concentrated catalyst slurry that is ready for recycle or regeneration. The wax will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e. 200-300{degrees}C. Initial work is being performed using n-hexane as the solvent. The success of the projects depends on two major factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, the must be accomplished without entraining the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds, i.e., a constant carbon-number distribution of the alkanes in the wax slurry must be maintained at steady-state column operation. The project includes three tasks (1) equilibrium solubility measurements, (2) thermodynamic modeling, and (3) process design studies.

  5. 21 CFR 178.3710 - Petroleum wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... derived from coconut oil and the C16 and C18 groups are derived from tallow. (e) Petroleum wax may contain... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Petroleum wax. 178.3710 Section 178.3710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR...

  6. Waxes: A Forgotten Topic in Lipid Teaching.

    ERIC Educational Resources Information Center

    Dominguez, Eva; Heredia, Antonio

    1998-01-01

    Reviews the biological importance of the lipids categorized as waxes and describes some of the organic chemistry of these compounds. Presents a short laboratory exercise on the extraction of plant waxes and their analysis by thin layer chromatography. (Author/CCM)

  7. Poly-3-hydroxy butyric acid interaction with the transgenic flax fibers: FT-IR and Raman spectra of the composite extracted from a GM flax

    NASA Astrophysics Data System (ADS)

    Wróbel-Kwiatkowska, Magdalena; Żuk, Magdalena; Szopa, Jan; Dymińska, Lucyna; Mączka, Mirosław; Hanuza, Jerzy

    2009-07-01

    The FT-IR and FT-Raman studies have been performed on commercial 3-hydroxy-butyric acid, commercial poly-3-hydroxy butyric acid as well as poly-3-hydroxy butyric acid (PHB) produced by bacteria. The data were compared to those obtained for poly-3-hydroxy butyric acid extracted from natural and genetically modified flax. Genetically modified flax was generated by expression of three bacterial genes coding for synthesis of poly-3-hydroxy butyric acid. Thus transgenic flaxes were enhanced with different amount of the PHB. The discussion of polymer structure and vibrational properties has been done in order to get insight into differences among these materials. The interaction between the cellulose of flax fibers and embedded poly-3-hydroxybutyric acid has been also discussed. The spectroscopic data provide evidences for structural changes in cellulose and in PHB when synthesized in fibers. Based on this data it is suggesting that cellulose and PHB interact by hydrogen and ester bonds.

  8. Bubble size and gas-liquid interfacial area measurements using molten paraffin waxes in bubble columns

    SciTech Connect

    Bukur, D.B.; Patel, S.A.; Daly, J.G.; Raphael, M.L.

    1987-01-01

    Experiments were conducted in 0.05 m ID and 0.23 m ID by 3 m tall bubble columns with different types of molten waxes as the liquid medium and nitrogen as the gas, under processing conditions typical or Fischer-Tropsch synthesis over iron catalysts (i.e. gas velocities up to 0.15 m s, and temperatures between 200 and 270/sup 0/C) to estimate gas liquid interfacial area from measured values of average gas hold-up and Sauter mean bubble diameter. The gas hold-up was estimated from visual observations of the expanded and static liquid heights, and the Sauter was estimated from bubble size measurements obtained by photography and dynamic gas disengagement. The paraffin wax (FT-300) used in the authors' studies is non-coalescing and has a tendency to foam. The amount of foam is greater for runs conducted in the order of increasing gas velocities, than in runs with decreasing velocities. Thus, two values of hold-up are possible and the start-up procedure determines which one will be attained. At higher gas velocities (> 0.05 m/s) the foam disappears and a transition to the slug flow, churn-turbulent regime takes place. Reactor waxes are coalescing in nature and do not produce foam. Despite similar hold-ups for the different waxes at higher gas velocities, the Sauters are significantly different and this is reflected in the specific gas-liquid interfacial areas, with larger values obtained with the paraffin wax compared to values with reactor waxes.

  9. Multi-stage wax hydrocracking

    SciTech Connect

    Lipinski, J.J.; Nye, J.R.; Soudek, M.

    1991-02-19

    This patent describes improvement in a process for the shape selective catalytic dewaxing of a wax containing feed. It consists of at least one of atmospheric gas oil and vacuum gas oil by passing the feed with about 1000 to 5000 standard cubic feet per barrel of hydrogen over a dewaxing catalyst comprising a shape selective zeolite to produce a dewaxed product and wherein the hydrogen is added to retard catalyst aging. The improvement comprises conducting the dewaxing reaction in at least two states, with a first stage containing at least 20 wt. % of the dewaxing catalyst and in at least one second stage containing at least 20 wt. % of the dewaxing catalyst and adding at least a portion of the hydrogen downstream of the first stage reactor wherein the total hydrogen to the second stage is greater than the total hydrogen to the first stage.

  10. Modified paraffin wax for improvement of histological analysis efficiency.

    PubMed

    Lim, Jin Ik; Lim, Kook-Jin; Choi, Jin-Young; Lee, Yong-Keun

    2010-08-01

    Paraffin wax is usually used as an embedding medium for histological analysis of natural tissue. However, it is not easy to obtain enough numbers of satisfactory sectioned slices because of the difference in mechanical properties between the paraffin and embedded tissue. We describe a modified paraffin wax that can improve the histological analysis efficiency of natural tissue, composed of paraffin and ethylene vinyl acetate (EVA) resin (0, 3, 5, and 10 wt %). Softening temperature of the paraffin/EVA media was similar to that of paraffin (50-60 degrees C). The paraffin/EVA media dissolved completely in xylene after 30 min at 50 degrees C. Physical properties such as the amount of load under the same compressive displacement, elastic recovery, and crystal intensity increased with increased EVA content. EVA medium (5 wt %) was regarded as an optimal composition, based on the sectioning efficiency measured by the numbers of unimpaired sectioned slices, amount of load under the same compressive displacement, and elastic recovery test. Based on the staining test of sectioned slices embedded in a 5 wt % EVA medium by hematoxylin and eosin (H&E), Masson trichrome (MT), and other staining tests, it was concluded that the modified paraffin wax can improve the histological analysis efficiency with various natural tissues.

  11. 21 CFR 178.3720 - Petroleum wax, synthetic.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Petroleum wax, synthetic. 178.3720 Section 178... § 178.3720 Petroleum wax, synthetic. Synthetic petroleum wax may be safely used in applications and under the same conditions where naturally derived petroleum wax is permitted in subchapter B of...

  12. 21 CFR 172.888 - Synthetic petroleum wax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Synthetic petroleum wax. 172.888 Section 172.888... Synthetic petroleum wax. Synthetic petroleum wax may be safely used in or on foods in accordance with the following conditions: (a) Synthetic petroleum wax is a mixture of solid hydrocarbons, paraffinic in...

  13. 21 CFR 172.888 - Synthetic petroleum wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Synthetic petroleum wax. 172.888 Section 172.888... CONSUMPTION Multipurpose Additives § 172.888 Synthetic petroleum wax. Synthetic petroleum wax may be safely used in or on foods in accordance with the following conditions: (a) Synthetic petroleum wax is...

  14. 21 CFR 178.3720 - Petroleum wax, synthetic.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Petroleum wax, synthetic. 178.3720 Section 178.3720... Certain Adjuvants and Production Aids § 178.3720 Petroleum wax, synthetic. Synthetic petroleum wax may be safely used in applications and under the same conditions where naturally derived petroleum wax...

  15. 21 CFR 172.888 - Synthetic petroleum wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Synthetic petroleum wax. 172.888 Section 172.888... CONSUMPTION Multipurpose Additives § 172.888 Synthetic petroleum wax. Synthetic petroleum wax may be safely used in or on foods in accordance with the following conditions: (a) Synthetic petroleum wax is...

  16. 21 CFR 172.888 - Synthetic petroleum wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Synthetic petroleum wax. 172.888 Section 172.888... CONSUMPTION Multipurpose Additives § 172.888 Synthetic petroleum wax. Synthetic petroleum wax may be safely used in or on foods in accordance with the following conditions: (a) Synthetic petroleum wax is...

  17. 21 CFR 172.888 - Synthetic petroleum wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Synthetic petroleum wax. 172.888 Section 172.888... CONSUMPTION Multipurpose Additives § 172.888 Synthetic petroleum wax. Synthetic petroleum wax may be safely used in or on foods in accordance with the following conditions: (a) Synthetic petroleum wax is...

  18. Improved wax mold technique forms complex passages in solid structures

    NASA Technical Reports Server (NTRS)

    Hellbaum, R. F.; Page, A. D.; Phillips, A. R.

    1971-01-01

    Low-cost fabricating technique produces minute, complex air passages in fluidic devices. Air jet interactions in these function as electronic and electromechanical control systems. Wax cores are fabricated without distortion by two-wax process using nonsoluble pattern-wax and water-soluble wax. Significant steps in fabrication process are discussed.

  19. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Rice bran wax. 172.890 Section 172.890 Food and... Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is the refined wax obtained from rice bran and meets the...

  20. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Rice bran wax. 172.890 Section 172.890 Food and... Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is the refined wax obtained from rice bran and meets the...

  1. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Rice bran wax. 172.890 Section 172.890 Food and... Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is the refined wax obtained from rice bran and meets the...

  2. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Rice bran wax. 172.890 Section 172.890 Food and... Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is the refined wax obtained from rice bran and meets the...

  3. 21 CFR 872.6890 - Intraoral dental wax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Intraoral dental wax. 872.6890 Section 872.6890...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6890 Intraoral dental wax. (a) Identification. Intraoral dental wax is a device made of wax intended to construct patterns from which custom made...

  4. 21 CFR 872.6890 - Intraoral dental wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Intraoral dental wax. 872.6890 Section 872.6890...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6890 Intraoral dental wax. (a) Identification. Intraoral dental wax is a device made of wax intended to construct patterns from which custom made...

  5. 21 CFR 872.6890 - Intraoral dental wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Intraoral dental wax. 872.6890 Section 872.6890...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6890 Intraoral dental wax. (a) Identification. Intraoral dental wax is a device made of wax intended to construct patterns from which custom made...

  6. 21 CFR 872.6890 - Intraoral dental wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Intraoral dental wax. 872.6890 Section 872.6890...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6890 Intraoral dental wax. (a) Identification. Intraoral dental wax is a device made of wax intended to construct patterns from which custom made...

  7. 21 CFR 872.6890 - Intraoral dental wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intraoral dental wax. 872.6890 Section 872.6890...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6890 Intraoral dental wax. (a) Identification. Intraoral dental wax is a device made of wax intended to construct patterns from which custom made...

  8. Methods for predicting wax precipitation and deposition

    SciTech Connect

    Weingarten, J.S.; Euchner, J.A.

    1988-02-01

    Removal of wax from wells and flowlines can account for significant additional operating costs. To evaluate these potential costs, the operating conditions that allow waxes to precipitate in the wellbore must be identified, and deposition rates must be estimated to determine the costs associated with removal of wax deposits. Presented in this paper are laboratory and analytic methods that can be used to estimate both the critical operating conditions and the deposition rates. The laboratory tests and analysis presented may be used to characterize any type of oil.

  9. Methods for predicting wax precipitation and deposition

    SciTech Connect

    Weingarten, J.S.; Euchner, J.A.

    1986-01-01

    Removal of wax from wells and flowlines can account for significant additional operating costs. To evaluate these potential costs, two things must be known. First, the operating conditions which allow waxes to precipitate in the wellbore must be identified. Second, deposition rates must be estimated to determine the costs associated with removal of wax deposits. Presented in this paper are laboratory and analytical methods which can be used to estimate both the critical operating conditions and the deposition rates. The laboratory tests and analysis presented may be used to characterize any type of oil.

  10. Detection of environmental deterioration in fiber reinforced composites by Ft-Raman spectroscopy. Phase I. Final report, 30 July 1993-30 April 1994

    SciTech Connect

    Farquharson, S.; Bananno, A.; Basilakis, R.; Carangelo, M.; DiTaranto, M.

    1994-05-01

    A number of advanced fiber reinforced organic matrix composites are being developed and applied in the aerospace industry. In these applications, the composites may be exposed to a variety of harsh environments, which may induce chemical and physical changes in the composite material, and ultimately lead to component failure. The successful use of these composites, therefore, requires methods to reliably detect and assess these changes. During this Phase I Program, a fiber optic based Fourier transform Raman spectrometer was specifically developed to perform nondestructive evaluation of environmentally damaged composites. Specifically, graphite and Kevlar reinforced epoxy and polyimide composite samples were subjected to thermal cycling, moisture exposure and ultraviolet irradiation. Three point flexure tests were used to measure flexural strength, flexural modulus, failure strain and failure load to assess induced mechanical property changes in the composites. Reflectance infrared spectra of the sample surfaces, as well as transmission infrared spectra of evolved gas phase chemical species were used to further characterize these changes.

  11. 21 CFR 186.1555 - Japan wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... fruits of the oriental sumac, Rhus succedanea (Japan, Taiwan, and Indo-China), R. vernicifera (Japan), and R. trichocarpa (China, Indo-China, India, and Japan). Japan wax is soluble in hot alcohol,...

  12. Characteristics of wax extracted from lubricant basestocks

    SciTech Connect

    Guzauskas, J.F.; Abbott, F.P.; Baumgartner, N.R.

    1994-04-01

    This report describes a process for characterizing wax extracted from lubricant basestocks. The authors chose seven basestocks coming from different global regions and having a wide range of low-temperature properties. The wax was extracted from each basestock at-40{degrees}C using a cold-filtering method. Gas chromatography/mass spectroscopy (GC/MS), differential scanning calorimetry (DSC), thermal mechanical analysis (TMA), and optical microscopy (OM) were used to characterize these waxes. These data were compared to each basestock/s viscosity, pour point, and borderline pumping temperature, and some correlations were found between the wax characteristics and the cold temperature properties of the basestocks. This method of characterization can be useful when trying to select the optimal pour point depressant for engine lubricants. 10 refs., 24 figs., 5 tabs.

  13. 21 CFR 186.1555 - Japan wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... fruits of the oriental sumac, Rhus succedanea (Japan, Taiwan, and Indo-China), R. vernicifera (Japan), and R. trichocarpa (China, Indo-China, India, and Japan). Japan wax is soluble in hot alcohol,...

  14. 21 CFR 186.1555 - Japan wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... fruits of the oriental sumac, Rhus succedanea (Japan, Taiwan, and Indo-China), R. vernicifera (Japan), and R. trichocarpa (China, Indo-China, India, and Japan). Japan wax is soluble in hot alcohol,...

  15. 21 CFR 186.1555 - Japan wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... fruits of the oriental sumac, Rhus succedanea (Japan, Taiwan, and Indo-China), R. vernicifera (Japan), and R. trichocarpa (China, Indo-China, India, and Japan). Japan wax is soluble in hot alcohol,...

  16. Lignin analysis by FT-Raman spectroscopy

    SciTech Connect

    Agarwal, U.P.; Obst, J.R.; Cannon, A.B.

    1996-10-01

    Traditional methods of lignin analysis, such as Klason (acid insoluble) lignin determinations, give satisfactory results, are widely accepted, and often are considered as standard analyses. However, the Klason lignin method is laborious and time consuming; it also requires a fairly large-amount of isolated analyte. FT-Raman spectroscopy offers an opportunity to simplify and speed up lignin analyses. FT-Raman data for a number of hardwoods (angiosperms) and softwoods (gymnosperms) are compared with data obtained using other analytical methods, including Klason lignin (with corrections for acid soluble lignin), acetyl bromide, and FT-IR determinations. In addition, 10 different specimens of Nothofagus dombeyii (chosen because of the widely varying syringyl:guaiacyl monomer compositions of their lignins) were also analyzed. Lignin monomer compositions were determined by thioacidolysis of by nitrobenzene oxidation.

  17. Oxidized wax as compatibilizer in linear low-density polyethylene-clay nanocomposites: x-ray diffraction and dynamic mechanical analysis.

    PubMed

    Geethamma, V G; Luyt, Adriaan S

    2008-04-01

    Oxidized paraffin wax was used as a compatibilizer in composites of linear low-density polyethylene and layered nano silicate clays. X-ray diffraction analyses were carried out to investigate the crystalline morphology of five types of clays, oxidized wax, and their composites with LLDPE. The composites exhibited different X-ray diffraction and dynamic mechanical behaviour in the presence of different clays. Generally, the composites retained the partially crystalline behaviour of LLDPE, and no exfoliation was observed. Increased amount of wax did not change the morphology in most cases. The incorporation of clay resulted in an observable increase in the storage modulus of LLDPE. These values also increased with the addition of oxidized wax for most of the composites. The loss modulus increased with the amount of clay, irrespective of its nature. In most cases these values also increased with the incorporation of wax. The composites with 10% clay and 10% oxidized wax showed the highest storage and loss moduli, irrespective of the nature of the clay. The tan delta values did not change considerably with the addition of clay or wax.

  18. Solidification of N-Octadecane paraffin wax

    SciTech Connect

    Deal, R.; Irby, R.; Keshock, E.; Solomon, A.D.

    1982-05-01

    Four freezing experiments with N-Octadecane paraffin wax are described. Their results are analyzed using a variety of mathematical techniques for conduction phase-change problems. From such mathematical analyses it is concluded, among other things, that the effective thermal conductivity of the solid wax in our case is about 3.5 times the literature value; this value was verified by independent experimental measurements.

  19. Tectonic microplates: laying it down on wax

    NASA Astrophysics Data System (ADS)

    Katz, R. R.; Bodenschatz, E.

    2008-12-01

    We present a wax analogue model of sea-floor spreading that produces rotating, growing microplates. Wax microplates are kinematically similar to sea-floor tectonic microplates in terms of spreading rate and growth rate. Furthermore, their spiral pseudofault geometry is quantitatively consistent with Schouten's oceanic microplate model. These results suggest that Schouten's edge-driven microplate model captures the kinematics of tectonic microplate evolution on Earth. We propose a theory for the formation of microplates.

  20. Molten Wax As A Dust Control Agent

    SciTech Connect

    Carter, E.E.

    2008-07-01

    Molten wax shows considerable promise as a fixative and dust control agent in demolition of radioactively contaminated facilities. Sticky molten wax, modified with special surfactants and wetting agents, is capable of not only coating materials but also penetrating into friable or dusty materials and making them incapable of becoming airborne during demolition. Wax also shows significant promise for stabilization of waste residuals that may be contained in buildings undergoing demolition. Some of the building materials that have been tested to date include concrete, wood, sheet-rock, fiber insulation, lime, rock, and paper. Protective clothing, clay, sand, sulfur, and bentonite clay have been tested as surrogates for certain waste materials that may be encountered during building demolition. The paper describes several potential applications of molten wax for dust control in demolition of radioactive contaminated facilities. As a case-study, this paper describes a research test performed for a pipeline closure project being completed by the Idaho Cleanup Project at the Idaho National Laboratory. The project plans to excavate and remove a section of buried Duriron drain piping containing highly radioactive and friable and 'flighty' waste residuals. A full-scale pipeline mockup containing simulated waste was buried in sand to simulate the direct-buried subsurface condition of the subject piping. The pipeline was pre-heated by drawing hot air through the line with a HEPA vacuum blower unit. Molten wax was pumped into the line and allowed to cool. The line was then broken apart in various places to evaluate the permeation performance of the wax. The wax fully permeated all the surrogate materials rendering them non-friable with a consistency similar to modeling clay. Based on the performance during the mockup, it is anticipated that the wax will be highly effective in controlling the spread of radiological contamination during pipe demolition activities. A larger test

  1. Wax and flow in diesel fuels

    SciTech Connect

    Zielinski, J.; Rossi, F.

    1984-01-01

    The formation of wax crystals in diesel fuels during winter use is a well known phenomenon. The industry has created specifications to insure satisfactory diesel operation under winter conditions by lowering the cloud point with kerosene dilutions or equipment modifications. These specifictions create a potential economic penalty to the refiner. An alternate solution to these cold flow problems include the use of chemical additives. This paper discusses some fundamentals related to the chemical additive approach, namely wax crystal modification.

  2. Uniform discotic wax particles via electrospray emulsification.

    PubMed

    Mejia, Andres F; He, Peng; Luo, Dawei; Marquez, Manuel; Cheng, Zhengdong

    2009-06-01

    We present a novel colloidal discotic system: the formation and self-assembling of wax microdisks with a narrow size distribution. Uniform wax emulsions are first fabricated by electrospraying of melt alpha-eicosene. The size of the emulsions can be flexibly tailored by varying the flow rate of the discontinuous phase, its electric conductivity, and the applied voltage. The process of entrainment of wax droplets, vital for obtaining uniform emulsions, is facilitated by the reduction of air-water surface tension and the density of the continuous phase. Then uniform wax discotic particles are produced via phase transition, during which the formation of a layered structure of the rotator phase of wax converts the droplets, one by one, into oblate particles. The time span for the conversion from spherical emulsions to disk particles is linearly dependent on the size of droplets in the emulsion, indicating the growth of a rotator phase from surface to the center is the limiting step in the shape transition. Using polarized light microscopy, the self-assembling of wax disks is observed by increasing disk concentration and inducing depletion attraction among disks, where several phases, such as isotropic, condensed, columnar stacking, and self-assembly of columnar rods are present sequentially during solvent evaporation of a suspension drop. PMID:19383560

  3. Uniform discotic wax particles via electrospray emulsification.

    PubMed

    Mejia, Andres F; He, Peng; Luo, Dawei; Marquez, Manuel; Cheng, Zhengdong

    2009-06-01

    We present a novel colloidal discotic system: the formation and self-assembling of wax microdisks with a narrow size distribution. Uniform wax emulsions are first fabricated by electrospraying of melt alpha-eicosene. The size of the emulsions can be flexibly tailored by varying the flow rate of the discontinuous phase, its electric conductivity, and the applied voltage. The process of entrainment of wax droplets, vital for obtaining uniform emulsions, is facilitated by the reduction of air-water surface tension and the density of the continuous phase. Then uniform wax discotic particles are produced via phase transition, during which the formation of a layered structure of the rotator phase of wax converts the droplets, one by one, into oblate particles. The time span for the conversion from spherical emulsions to disk particles is linearly dependent on the size of droplets in the emulsion, indicating the growth of a rotator phase from surface to the center is the limiting step in the shape transition. Using polarized light microscopy, the self-assembling of wax disks is observed by increasing disk concentration and inducing depletion attraction among disks, where several phases, such as isotropic, condensed, columnar stacking, and self-assembly of columnar rods are present sequentially during solvent evaporation of a suspension drop.

  4. Wax-bonding 3D microfluidic chips.

    PubMed

    Gong, Xiuqing; Yi, Xin; Xiao, Kang; Li, Shunbo; Kodzius, Rimantas; Qin, Jianhua; Wen, Weijia

    2010-10-01

    We report a simple, low-cost and detachable microfluidic chip incorporating easily accessible paper, glass slides or other polymer films as the chip materials along with adhesive wax as the recycling bonding material. We use a laser to cut through the paper or film to form patterns and then sandwich the paper and film between glass sheets or polymer membranes. The hot-melt adhesive wax can realize bridge bonding between various materials, for example, paper, polymethylmethacrylate (PMMA) film, glass sheets, or metal plate. The bonding process is reversible and the wax is reusable through a melting and cooling process. With this process, a three-dimensional (3D) microfluidic chip is achievable by vacuating and venting the chip in a hot-water bath. To study the biocompatibility and applicability of the wax-based microfluidic chip, we tested the PCR compatibility with the chip materials first. Then we applied the wax-paper based microfluidic chip to HeLa cell electroporation (EP). Subsequently, a prototype of a 5-layer 3D chip was fabricated by multilayer wax bonding. To check the sealing ability and the durability of the chip, green fluorescence protein (GFP) recombinant Escherichia coli (E. coli) bacteria were cultured, with which the chemotaxis of E. coli was studied in order to determine the influence of antibiotic ciprofloxacin concentration on the E. coli migration.

  5. Preparation of waxes and humic acids from brown coal from the Sergeevskoe deposit

    SciTech Connect

    L.P. Noskova; A.V. Rokhin; A.P. Sorokin

    2007-06-15

    The comparative extraction of coal with organic solvents was performed. Humic acids were separated from solid residues. The yields, particle-size distributions, and chemical compositions of the resulting products were analyzed. It was demonstrated that brown-coal wax and humic fertilizers can potentially be obtained using coal from the Sergeevskoe deposit.

  6. Stomatal Density Influences Leaf Water and Leaf Wax D/H Values in Arabidopsis

    NASA Astrophysics Data System (ADS)

    Lee, H.; Feakins, S. J.; Sternberg, L. O.

    2014-12-01

    The hydrogen isotopic composition (δD) of plant leaf wax is a powerful tool to study the hydrology of past and present environments. The δD value of leaf waxes is known to primarily reflect the δD value of source water, modified by biological fractionations commonly summarized as the 'net or apparent' fractionation. It remains a challenge, however, to quantitatively relate the isotopic composition of the end product (wax) back to that of the precursor (water) because multiple isotope effects contributing to the net fractionation are not yet well understood. Transgenic variants have heretofore unexplored potential to isolate individual isotope effects. Here we report the first hydrogen isotopic measurements from transgenic Arabidopsis thaliana plants with calculations of leaf water enrichment, net and biosynthetic fractionation values from measured δD of plant waters and leaf wax n-alkanes. We employed transgenic Arabidopsis leaves, engineered to have different stomatal density, by differential expression of the stomatal growth hormone stomagen. Comparison of variants and wild types allow us to isolate the effects of stomatal density on leaf water and the net fractionation expressed by leaf wax biomarkers. Results show that transgenic leaves with denser pores have more enriched leaf water and leaf wax δD values than wild type and even more so than transgenic leaves with sparse stomata (difference of 10 ‰). Our findings that stomatal density controls leaf water and leaf wax δD values adds insights into the cause of variations in net fractionations between species, as well as suggesting that geological variations in stomatal density may modulate the sedimentary leaf wax δD record. In nature, stomatal density varies between species and environments, and all other factors being equal, this will contribute to variations in fractionations observed. Over geological history, lower stomatal densities occur at times of elevated pCO2; our findings predict reduced leaf

  7. Oligomers Formed Through In-cloud Metylglyoxal Reactions: Chemical Composition, Properties, and Mechanisms Investigated by Ultra-high Resolution FT-ICR Mass Spectrometry

    EPA Science Inventory

    Secondary organic aerosol (SOA) is a substantial component of total atmospheric organic particulate matter, but little is known about the composition of SOA formed through cloud processing. We conducted aqueous phase photooxidation experiments of methylglyoxal and hydroxyl radica...

  8. Coatings and films derived from clay/wax nanocomposites

    DOEpatents

    Chaiko, David J.; Leyva, Argentina A.

    2006-11-14

    The invention provides methods for making clay/wax nanocomposites and coatings and films of same with improved chemical resistance and gas barrier properties. The invention further provides methods for making and using emulsions of such clay/wax nanocomposites. Typically, an organophillic clay is combined with a wax or wax/polymer blend such that the cohesion energy of the clay matches that of the wax or wax/polymer blend. Suitable organophilic clays include mica and phyllosilicates that have been surface-treated with edge or edge and surface modifying agents. The resulting nanocomposites have applications as industrial coatings and in protective packaging.

  9. FORMULATION AND EVALUATION OF RICE BRAN WAX AS OINTMENT BASE

    PubMed Central

    Bhalekar, M; Manish, Lavhale; Krishna, Sini

    2004-01-01

    Rice Bran wax is obtained from natural sources and is abundantly available in the country. Rice bran wax is suitable for use in chocolate enrobes, as an enteric coating for candy and lozenges, as a plasticizing material in chewing gums etc. Present study attempts to find if rice bran wax is useful as ointment base. The oleaginous type ointment base is prepared by using rice bran wax and evaluated for speardabililty, water number and active ingredient diffusibility. The results obtained in the present study indicate, rice bran wax can be used as a good component in ointment base, comparable with white wax. PMID:22557151

  10. Chemical profiling of the major components in natural waxes to elucidate their role in liquid oil structuring.

    PubMed

    Doan, Chi Diem; To, Chak Ming; De Vrieze, Mike; Lynen, Frederic; Danthine, Sabine; Brown, Allison; Dewettinck, Koen; Patel, Ashok R

    2017-01-01

    Elucidating the composition of waxes is of utmost importance to explain their behavior in liquid oil structuring. The chemical components (hydrocarbons - HCs, free fatty acids - FFAs, free fatty alcohols - FALs and wax esters - WEs) of natural waxes were analyzed using HPLC-ELSD and GC-MS followed by evaluation of their oil structuring properties. The gel strength, including the average storage modulus and oscillation yield stress, displayed a negative correlation with FALs and a positive correlation with HCs, FFAs and WEs. The components dictating the gel strength are HCs, FFAs and WEs in a descending order of importance. The consistency of the oleogels increased with the increasing amount of FFAs and HCs and the decreasing amount of WEs and FALs. The presence of more WEs results in a strong but brittle gel with a high initial flow yield stress. We believe these results might be useful in selecting the right waxes to combine in certain fat-based food products. PMID:27507530

  11. Chemical profiling of the major components in natural waxes to elucidate their role in liquid oil structuring.

    PubMed

    Doan, Chi Diem; To, Chak Ming; De Vrieze, Mike; Lynen, Frederic; Danthine, Sabine; Brown, Allison; Dewettinck, Koen; Patel, Ashok R

    2017-01-01

    Elucidating the composition of waxes is of utmost importance to explain their behavior in liquid oil structuring. The chemical components (hydrocarbons - HCs, free fatty acids - FFAs, free fatty alcohols - FALs and wax esters - WEs) of natural waxes were analyzed using HPLC-ELSD and GC-MS followed by evaluation of their oil structuring properties. The gel strength, including the average storage modulus and oscillation yield stress, displayed a negative correlation with FALs and a positive correlation with HCs, FFAs and WEs. The components dictating the gel strength are HCs, FFAs and WEs in a descending order of importance. The consistency of the oleogels increased with the increasing amount of FFAs and HCs and the decreasing amount of WEs and FALs. The presence of more WEs results in a strong but brittle gel with a high initial flow yield stress. We believe these results might be useful in selecting the right waxes to combine in certain fat-based food products.

  12. A new method for evaluating wax inhibitors and drag reducers

    SciTech Connect

    Hsu, J.J.C.; Brubaker, J.P.

    1995-12-01

    Conventional wax inhibitor evaluation methods such as cold finger and laminar flow loop are not adequate and accurate for evaluating wax inhibitors to be used in a wide operating temperature range and flow regimes such as North Sea subsea transport pipelines. A new method has been developed to simultaneously measure fluid rheology change and wax inhibition and to evaluate wax inhibitors or drag reducers at the field operating conditions. Selection criteria have been defined to search for an effective wax inhibitor. The criteria ensure the chemical selected is the most effective one for the specific oil and flow conditions. The operation cost savings by this accurate method is significant. Nine chemical companies joined the project of finding an wax inhibitor for a North Sea prospect. More than twenty wax inhibitors have been tested and evaluated with this new method for several waxy oil fields. The new method provides data of fluid rheology, war deposition rates and wax inhibition in the operating temperature range, overall average wax inhibition and degree of fluid flow improvement. These data are important to evaluate a wax inhibitor or drag reducer. Most of the wax inhibitors tested have good wax inhibition at high temperatures, but not many chemicals work well at low temperatures. The chemical tested may improved fluid flow behavior at low temperature but not wax deposition. Drag reducers tested did not work well at North Sea seabed temperature.

  13. Separation of Fischer-Tropsch wax from catalyst using supercritical fluid extraction. Quarterly technical progress report, April 1, 1996--June 30, 1996

    SciTech Connect

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

    1996-11-01

    The objective of this research project is to evaluate the potential of SCF extraction for separating the catalyst slurry of a Fischer- Tropsch (F-T) slurry bubble column (SBC) reactor into two fractions: (1) a catalyst-free wax containing less than 10 ppm particulate matter and (2) a concentrated catalyst slurry that is ready for recycle or regeneration. The wax will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300{degrees}C. Initial work is being performed using n-hexane as the solvent. The success of the project depends on two major factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, this must be accomplished without entraining the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds, i.e., a constant carbon-number distribution of the alkanes in the wax slurry must be maintained at steady-state column operation. To implement our objectives, the following task structure is being implemented: Task 1 equilibrium solubility measurements; Task 2 thermodynamic modeling; and Task 3 process design studies. Progress reports are presented for each task.

  14. Separation of Fischer-Tropsch wax from catalyst using supercritical fluid extraction. Quarterly technical progress report, 1 January 1996--31 March 1996

    SciTech Connect

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

    1996-09-01

    The objective of this research project is to evaluate the potential of supercritical fluid extraction for separating the catalyst slurry of a Fischer-Tropsch (F-T) slurry bubble column (SBC) reactor into two fractions: (1) a catalyst-free wax containing less than 10 ppm particulate matter and (2) a concentrated catalyst slurry that is ready for recycle or regeneration. The wax will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200--300 {degrees}C. Initial work is being performed using n-hexane as the solvent. The success of the project depends on two major factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, this must be accomplished without entraining the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds, i.e., a constant carbon-number distribution of the alkanes in the wax slurry must be maintained at steady-state column operation. During this quarter work focused on task 1b, experimental measurement of selected model systems. Vapor-liquid equilibrium experiments for the n- hexane/squalane system, which we initiated in the previous quarter, were continued and results are discussed in this report.

  15. The Thermodielectric Effect in Paraffin Wax

    NASA Astrophysics Data System (ADS)

    Tomas, Martin; Novotny, Pavel

    2015-02-01

    This paper deals with results of the thermodielectric effect measurement. A paraffin wax as a dielectric material was investigated via differential scanning calorimetry and potentiometry during a phase transition. Possible description of the thermodielectric effect based on fundamental laws of thermodynamics is shown; to be more specific, the link between the potential difference and the latent heat is presented. The thermodynamic model of thermodielectric effect based on electrochemical equilibrium and charge generation at the solid/liquid interface is introduced. Results of the thermodielectric effect measurement are used for the calculation of a molecular mass of the paraffin wax. The relation for a surface area (interface) between liquid and solid phase of the paraffin wax during solidification is derived from the presented theoretical description of the thermodielectric effect.

  16. Wax Point Determinations Using Acoustic Resonance Spectroscopy

    SciTech Connect

    Jubin, R.T.

    2002-04-08

    The thermodynamic characterization of the wax point of a given crude is essential in order to maintain flow conditions that prevent plugging of undersea pipelines. This report summarizes the efforts made towards applying an Acoustic Cavity Resonance Spectrometer (ACRS) to the determination of pressures and temperatures at which wax precipitates from crude. Phillips Petroleum Company, Inc., the CRADA participant, supplied the ACRS. The instrumentation was shipped to Dr. Thomas Schmidt of ORNL, the CRADA contractor, in May 2000 after preliminary software development performed under the guidance of Dr. Samuel Colgate and Dr. Evan House of the University of Florida, Gainesville, FL. Upon receipt it became apparent that a number of modifications still needed to be made before the ACRS could be precisely and safely used for wax point measurements. This report reviews the sequence of alterations made to the ACRS, as well as defines the possible applications of the instrumentation once the modifications have been completed.

  17. Microencapsulation of Flavors in Carnauba Wax

    PubMed Central

    Milanovic, Jelena; Manojlovic, Verica; Levic, Steva; Rajic, Nevenka; Nedovic, Viktor; Bugarski, Branko

    2010-01-01

    The subject of this study is the development of flavor wax formulations aimed for food and feed products. The melt dispersion technique was applied for the encapsulation of ethyl vanillin in wax microcapsules. The surface morphology of microparticles was investigated using scanning electron microscope (SEM), while the loading content was determined by HPLC measurements. This study shows that the decomposition process under heating proceeds in several steps: vanilla evaporation occurs at around 200 °C, while matrix degradation starts at 250 °C and progresses with maxima at around 360, 440 and 520 °C. The results indicate that carnauba wax is an attractive material for use as a matrix for encapsulation of flavours in order to improve their functionality and stability in products. PMID:22315575

  18. Wax Point Determinations Using Acoustic Resonance Spectroscopy

    SciTech Connect

    Bostick, D.T.; Jubin, R.T.; Schmidt, T.W.

    2001-06-01

    The thermodynamic characterization of the wax point of a given crude is essential in order to maintain flow conditions that prevent plugging of undersea pipelines. This report summarizes the efforts made towards applying an Acoustic Cavity Resonance Spectrometer (ACRS) to the determination of pressures and temperatures at which wax precipitates from crude. Phillips Petroleum Company, Inc., the CRADA participant, supplied the ACRS. The instrumentation was shipped to Dr. Thomas Schmidt of ORNL, the CRADA contractor, in May 2000 after preliminary software development performed under the guidance of Dr. Samuel Colgate and Dr. Evan House of the University of Florida, Gainesville, Fl. Upon receipt it became apparent that a number of modifications still needed to be made before the ACRS could be precisely and safely used for wax point measurements. This report reviews the sequence of alterations made to the ACRS, as well as defines the possible applications of the instrumentation once the modifications have been completed. The purpose of this Cooperative Research and Development Agreement (CRADA) between Phillips Petroleum Company, Inc. (Participant) and Lockheed Martin Energy Research Corporation (Contractor) was the measurement of the formation of solids in crude oils and petroleum products that are commonly transported through pipelines. This information is essential in the proper design, operation and maintenance of the petroleum pipeline system in the United States. Recently, new petroleum discoveries in the Gulf of Mexico have shown that there is a potential for plugging of undersea pipeline because of the precipitation of wax. It is important that the wax points of the expected crude oils be well characterized so that the production facilities for these new wells are capable of properly transporting the expected production. The goal of this work is to perform measurements of solids formation in crude oils and petroleum products supplied by the Participant. It is

  19. Interfamily variation in comb wax hydrocarbons produced by honey bees.

    PubMed

    Breed, M D; Page, R E; Hibbard, B E; Bjostad, L B

    1995-09-01

    The hydrocarbons of honeybee comb wax vary significantly between colonies. This variation is explained in part by genetic (familial) differences among colonies. Even though significant differences in wax hydrocarbons exist among families, there is a high level of consistency within and among families in a correlation analysis, indicating structural constancy in comb wax. The significance of these results in interpreting the potential role of comb wax in the nestmate recognition system of the honeybee is discussed.

  20. Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy as a Forensic Method to Determine the Composition of Inks Used to Print the United States One-cent Blue Benjamin Franklin Postage Stamps of the 19th Century.

    PubMed

    Brittain, Harry G

    2016-01-01

    Through the combined use of infrared (IR) absorption spectroscopy and attenuated total reflectance (ATR) sampling, the composition of inks used to print the many different types of one-cent Benjamin Franklin stamps of the 19th century has been established. This information permits a historical evaluation of the formulations used at various times, and also facilitates the differentiation of the various stamps from each other. In two instances, the ink composition permits the unambiguous identification of stamps whose appearance is identical, and which (until now) have only been differentiated through estimates of the degree of hardness or softness of the stamp paper, or through the presence or absence of a watermark in the paper. In these instances, the use of ATR Fourier transform infrared spectroscopy (FT-IR) spectroscopy effectively renders irrelevant two 100-year-old practices of stamp identification. Furthermore, since the use of ATR sampling makes it possible to obtain the spectrum of a stamp still attached to its cover, it is no longer necessary to identify these blue Franklin stamps using their cancellation dates.

  1. 21 CFR 178.3720 - Petroleum wax, synthetic.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Petroleum wax, synthetic. 178.3720 Section 178... SANITIZERS Certain Adjuvants and Production Aids § 178.3720 Petroleum wax, synthetic. Synthetic petroleum wax may be safely used in applications and under the same conditions where naturally derived petroleum...

  2. 21 CFR 178.3720 - Petroleum wax, synthetic.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Petroleum wax, synthetic. 178.3720 Section 178... SANITIZERS Certain Adjuvants and Production Aids § 178.3720 Petroleum wax, synthetic. Synthetic petroleum wax may be safely used in applications and under the same conditions where naturally derived petroleum...

  3. 21 CFR 178.3720 - Petroleum wax, synthetic.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Petroleum wax, synthetic. 178.3720 Section 178... SANITIZERS Certain Adjuvants and Production Aids § 178.3720 Petroleum wax, synthetic. Synthetic petroleum wax may be safely used in applications and under the same conditions where naturally derived petroleum...

  4. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Rice bran wax. 172.890 Section 172.890 Food and... PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is...

  5. 7 CFR 3201.79 - Candles and wax melts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Candles and wax melts. 3201.79 Section 3201.79... Designated Items § 3201.79 Candles and wax melts. (a) Definition. Products composed of a solid mass and... wax melts. By that date, Federal agencies that have the responsibility for drafting or...

  6. 7 CFR 3201.79 - Candles and wax melts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Candles and wax melts. 3201.79 Section 3201.79... Designated Items § 3201.79 Candles and wax melts. (a) Definition. Products composed of a solid mass and... wax melts. By that date, Federal agencies that have the responsibility for drafting or...

  7. Morphology and networks of sunflower wax crystals in organogel

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant waxes are considered as promising alternatives to unhealthy solid fats such as trans fats and saturated fats in structured food products including margarines and spreads. Sunflower wax is of a great interest due to its strong gelling ability. Morphology of sunflower wax crystals formed in soyb...

  8. Triterpenoid profile of flower and leaf cuticular waxes of heather Calluna vulgaris.

    PubMed

    Szakiel, Anna; Niżyński, Bartosz; Pączkowski, Cezary

    2013-08-01

    Analysis of the main triterpenoid profile of chloroform-soluble cuticular waxes of heather flowers and leaves by GC-MS revealed the following composition: five triterpene acids - betulinic, oleanolic, ursolic, 3-oxo-olean-12-en-28-oic and 3-oxo-ursan-12-en-28-oic; eight monohydroxyalcohols - α-amyrin, β-amyrin, cycloartanol, 24-methylenecycloartanol, friedelinol, germanicol, lupeol and taraxasterol; three dihydroxyalcohols - betulin, erythrodiol and uvaol; two aldehydes - oleanolic and ursolic; four ketones - α-amyrenone, 4-epi-friedelin, friedelin and taraxerone and seven steroids - campesterol, cholesterol, sitostanol, sitosterol, stigmasterol, stigmasta-3,5-dien-7-one and stigmastane-3,6-dione. Triterpenoids accounted for 20% and 65% by mass of flower and leaf waxes, respectively, which suggest that heather leaves represent a very promising source of these compounds. Ursolic acid was the principal triterpenoid in the cuticular wax of both organs, whereas among the neutral triterpenes, friedelin and uvaol were the most abundant in flowers and leaves, respectively. This report provides the first thorough overview of the triterpenoid composition of cuticular waxes of heather.

  9. 21 CFR 184.1976 - Candelilla wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... practice: in chewing gum as defined in § 170.3(n)(6) of this chapter and in hard candy as defined in § 170... obtained from the candelilla plant. It is a hard, yellowish-brown, opaque-to-translucent wax....

  10. 21 CFR 184.1976 - Candelilla wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... practice: in chewing gum as defined in § 170.3(n)(6) of this chapter and in hard candy as defined in § 170... obtained from the candelilla plant. It is a hard, yellowish-brown, opaque-to-translucent wax....

  11. 21 CFR 184.1976 - Candelilla wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... practice: in chewing gum as defined in § 170.3(n)(6) of this chapter and in hard candy as defined in § 170... obtained from the candelilla plant. It is a hard, yellowish-brown, opaque-to-translucent wax....

  12. 21 CFR 184.1976 - Candelilla wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... practice: in chewing gum as defined in § 170.3(n)(6) of this chapter and in hard candy as defined in § 170... obtained from the candelilla plant. It is a hard, yellowish-brown, opaque-to-translucent wax....

  13. 21 CFR 178.3850 - Reinforced wax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Reinforced wax. 178.3850 Section 178.3850 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) INDIRECT FOOD... producing, manufacturing, packing, processing, transporting, or holding food subject to the provisions...

  14. 21 CFR 172.886 - Petroleum wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... errors arising from contamination is great. It is of the greatest importance that all glassware be... contamination. As a precautionary measure it is recommended practice to rinse all glassware with purified... contamination of wax samples in handling and to assure absence of any extraneous material arising...

  15. Characterization of rice bran wax policosanol and its nanoemulsion formulation.

    PubMed

    Ishaka, Aminu; Umar Imam, Mustapha; Mahamud, Rozi; Zuki, Abu Bakar Zakaria; Maznah, Ismail

    2014-01-01

    Policosanol, a mixture of long-chain alcohols found in animal and plant waxes, has several biological effects; however, it has a bioavailability of less than 10%. Therefore, there is a need to improve its bioavailability, and one of the ways of doing this is by nanoemulsion formulation. Different droplet size distributions are usually achieved when emulsions are formed, which solely depends on the preparation method used. Mostly, emulsions are intended for better delivery with maintenance of the characteristics and properties of the leading components. In this study, policosanol was extracted from rice bran wax, its composition was determined by gas chromatography mass spectrophotometry, nanoemulsion was made, and the physical stability characteristics were determined. The results showed that policosanol nanoemulsion has a nanosize particle distribution below 100 nm (92.56-94.52 nm), with optimum charge distribution (-55.8 to -45.12 mV), pH (6.79-6.92) and refractive index (1.50); these were monitored and found to be stable for 8 weeks. The stability of policosanol nanoemulsion confers the potential to withstand long storage times. PMID:24872689

  16. Characterization of rice bran wax policosanol and its nanoemulsion formulation.

    PubMed

    Ishaka, Aminu; Umar Imam, Mustapha; Mahamud, Rozi; Zuki, Abu Bakar Zakaria; Maznah, Ismail

    2014-01-01

    Policosanol, a mixture of long-chain alcohols found in animal and plant waxes, has several biological effects; however, it has a bioavailability of less than 10%. Therefore, there is a need to improve its bioavailability, and one of the ways of doing this is by nanoemulsion formulation. Different droplet size distributions are usually achieved when emulsions are formed, which solely depends on the preparation method used. Mostly, emulsions are intended for better delivery with maintenance of the characteristics and properties of the leading components. In this study, policosanol was extracted from rice bran wax, its composition was determined by gas chromatography mass spectrophotometry, nanoemulsion was made, and the physical stability characteristics were determined. The results showed that policosanol nanoemulsion has a nanosize particle distribution below 100 nm (92.56-94.52 nm), with optimum charge distribution (-55.8 to -45.12 mV), pH (6.79-6.92) and refractive index (1.50); these were monitored and found to be stable for 8 weeks. The stability of policosanol nanoemulsion confers the potential to withstand long storage times.

  17. Characterization of rice bran wax policosanol and its nanoemulsion formulation

    PubMed Central

    Ishaka, Aminu; Umar Imam, Mustapha; Mahamud, Rozi; Zuki, Abu Bakar Zakaria; Maznah, Ismail

    2014-01-01

    Policosanol, a mixture of long-chain alcohols found in animal and plant waxes, has several biological effects; however, it has a bioavailability of less than 10%. Therefore, there is a need to improve its bioavailability, and one of the ways of doing this is by nanoemulsion formulation. Different droplet size distributions are usually achieved when emulsions are formed, which solely depends on the preparation method used. Mostly, emulsions are intended for better delivery with maintenance of the characteristics and properties of the leading components. In this study, policosanol was extracted from rice bran wax, its composition was determined by gas chromatography mass spectrophotometry, nanoemulsion was made, and the physical stability characteristics were determined. The results showed that policosanol nanoemulsion has a nanosize particle distribution below 100 nm (92.56–94.52 nm), with optimum charge distribution (−55.8 to −45.12 mV), pH (6.79–6.92) and refractive index (1.50); these were monitored and found to be stable for 8 weeks. The stability of policosanol nanoemulsion confers the potential to withstand long storage times. PMID:24872689

  18. Fruit cuticular waxes as a source of biologically active triterpenoids.

    PubMed

    Szakiel, Anna; Pączkowski, Cezary; Pensec, Flora; Bertsch, Christophe

    2012-06-01

    The health benefits associated with a diet rich in fruit and vegetables include reduction of the risk of chronic diseases such as cardiovascular disease, diabetes and cancer, that are becoming prevalent in the aging human population. Triterpenoids, polycyclic compounds derived from the linear hydrocarbon squalene, are widely distributed in edible and medicinal plants and are an integral part of the human diet. As an important group of phytochemicals that exert numerous biological effects and display various pharmacological activities, triterpenoids are being evaluated for use in new functional foods, drugs, cosmetics and healthcare products. Screening plant material in the search for triterpenoid-rich plant tissues has identified fruit peel and especially fruit cuticular waxes as promising and highly available sources. The chemical composition, abundance and biological activities of triterpenoids occurring in cuticular waxes of some economically important fruits, like apple, grape berry, olive, tomato and others, are described in this review. The need for environmentally valuable and potentially profitable technologies for the recovery, recycling and upgrading of residues from fruit processing is also discussed.

  19. H-Isotopic Fractionation During Biosynthesis of Leaf Waxes in C3 Plants: Trees vs. Grasses

    NASA Astrophysics Data System (ADS)

    Toney, J. L.; Hou, J.; Huang, Y.

    2006-12-01

    Recent studies indicate that hydrogen isotope (D/H) ratios of higher-plant leaf waxes in lake sediments have great potential to be used as a proxy for reconstructing past source water isotope composition and/or relative humidity on continents. However, hydrogen isotopic fractionation during biosynthesis of leaf waxes in various terrestrial plants remains poorly understood. A recent study of 7 terrestrial and aquatic plant types from a single site in Massachusetts shows that D/H ratios among different plant types can vary as much as 70‰, with the largest difference occurring between tree and grasses (Hou et al., in review). This variability may have been caused by different degrees of evapotranspiration among different plant types (e.g., trees vs. grasses), but could also be attributed to different biosynthetic isotopic fractionation. We designed a series of growth chamber experiments to trace the sources of hydrogen isotopic difference between trees and grasses. Five tree species [white ash (Fraxinus pennsylvanica), red oak (Quercus rubra), red maple (Acer rubrum), spruce (Picea sp.) and white cedar (Thuja occidentalis)] and three grass species [orchard grass (Dactylis glomerata), timothy weed (Phleum pratense), Foxtail (Setaria sp.)] were grown in a growth chamber under controlled conditions. Plants were irrigated with the same source water. We tracked hydrogen isotopic variation of water from source water to stem water to leaf water, and eventually to leaf waxes. Fifty-three leaf and stem samples were harvested. Water from these samples was vacuum-extracted and analyzed for D/H ratios, and compared with D/H ratios of corresponding leaf waxes. Our results allow us to determine whether evapotranspiration rates or intrinsic isotopic fractionation during biosynthesis was the dominant factor controlling the H isotopic ratios of leaf waxes in trees and grasses. Our results are also helpful for interpreting hydrogen isotopic variations of sedimentary leaf waxes.

  20. From buds to litter: seasonal changes in leaf wax concentrations and carbon isotopes and implications for the geologic past

    NASA Astrophysics Data System (ADS)

    Suh, Y. J.; Diefendorf, A. F.

    2014-12-01

    The carbon isotope composition (δ13C) of leaf waxes, such as n-alkanes, have extensively been used in paleoenvironmental studies for reconstruction of the past vegetation, climate and carbon cycling. There is however little information available on the seasonal variation of leaf wax concentration and δ13C in modern plants and when the δ13C signal is set. This lack of information confounds interpretations of leaf wax δ13C in sedimentary archives. To address this gap, this study investigates temporal changes in n-alkane and n-alkanoic acid δ13C values in several species (Acer rubrum, Acer saccharum, Ulmus Americana, Sassafras albidum, and Juniperus virginiana) within a single temperate deciduous forest stand in southern Ohio. We sampled atmospheric air, buds, leaves, leaf litter, and surface soil weekly during leaf flush and biweekly thereafter. In A. rubrum, A. saccharum, and U. Americana, buds had one or two dominant n-alkanes, such as C29 and C31. After leaf flush, the concentrations of shorter n-alkanes (C23~C27) significantly increased relative to the longer chain-lengths. We are currently analyzing remaining samples from the growing season and are analyzing bulk leaf and leaf wax (n-alkanes, n-alkanoic acids) δ13C values. This information will be important for identifying environmental and physiological controls on leaf wax δ13C and will improve interpretations of leaf wax δ13C preserved in the geologic record.

  1. Prediction of cloud point temperatures and amount of wax precipitation

    SciTech Connect

    Pedersen, K.S. )

    1995-02-01

    The paper presents a vapor-liquid-solid model for predicting phase equilibria of oil mixtures taking into account the possible formation of a wax phase. The gas and liquid phases are described using the Soave-Redlich-Kwong equation of state while the wax phase is assumed to be an ideal mixture. Only part of the heavy hydrocarbons are considered to be able to potentially enter into a wax phase. A procedure is developed for estimating the fraction of the heavy hydrocarbons which may potentially form wax. Calculation results agree very well with experimental wax precipitation data.

  2. Standard test method for solidification-point of petroleum wax

    SciTech Connect

    Not Available

    1980-01-01

    Scope: describes a procedure for rapidly determining the solidification point of petroleum wax. A 50-mg sample of wax is placed in a test tube at ambient temperature and heated above the solidification point of the wax sample. A thermocouple probe, attached to a recorder, is inserted into the wax sample, which is allowed to cool at room temperature. The thermocouple response of the cooling wax traces a curve on the chart paper of the recorder. The first significant change in the slope of the curve is the solidifiation point.

  3. Patient preference for waxed or unwaxed dental floss.

    PubMed

    Beaumont, R H

    1990-02-01

    The purpose of this study was to discover patient preference for waxed or unwaxed dental floss, and to learn more about individual flossing habits. One hundred patients randomly presenting for routine dental examinations volunteered to sample a brand of similar-appearing waxed and unwaxed dental floss. After flossing an anterior and a posterior contact area with both types, the patients indicated whether they preferred the waxed or unwaxed floss. The patients also answered questions concerning their flossing habits. Waxed floss was found to be preferred after sampling by 79% and unwaxed by 21%. An additional 50 patients sampled a different brand of waxed and unwaxed floss in a similar manner. In this group 78% preferred the waxed and 22% the unwaxed type. A final group of 50 patients compared mint flavored waxed floss with plain waxed floss of the same brand. In this group 56% preferred the mint flavored waxed floss, 24% the plain waxed floss, and 20% had no preference. A combined total of only 29.5% of the patients claimed to floss daily, 53.5% floss irregularly but at least once a week, while 17% do not floss even once a week. Waxed floss was purchased for home use by a combined patient total of 57.5%, unwaxed by 32%, and neither type by 10.5%. An unsubstantiated belief in the superiority of unwaxed floss has persisted to the present time.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Dewaxing process using agitated heat exchanger to chill solvent-oil and wax slurry to wax filtration temperature

    SciTech Connect

    Broadhurst, Th.E.

    1984-04-10

    In an improved process for dewaxing waxy hydrocarbon oils, wherein said waxy oil is cooled in an indirect chilling zone to a temperature greater than the wax separation temperature whereby wax is precipitated to form a wax-oil-solvent slurry, cooling the slurry to the wax separation temperature in an indirect chilling zone thereby precipitating a further portion of wax from said waxy oil and separating said precipitated wax from the wax-oil-solvent slurry in solid-liquid separation means, the improvement comprises using as the indirect chilling zone an indirect heat exchanger means operated at a high level of agitation. Expressed in terms of Impeller Reynolds Number the agitation is on the order of about 1,000 to 1,000,000. Alternatively, the direct chilling zone is totally replaced by the high agitation indirect heat exchanger means.

  5. Sintering of wax for controlling release from pellets.

    PubMed

    Singh, Reena; Poddar, S S; Chivate, Amit

    2007-09-14

    The purpose of the present study was to investigate incorporation of hydrophobic (ie, waxy) material into pellets using a thermal sintering technique and to evaluate the pellets in vitro for controlled release. Pellets prepared by extrusion-spheronization technology were formulated with a water-soluble drug, microcrystalline cellulose, and carnauba wax. Powdered carnauba wax (4%-20%) prepared by grinding or by emulsification was studied with an attempt to retard the drug release. The inclusion of ground or emulsified carnauba wax did not sustain the release of theophylline for more than 3 hours. Matrix pellets of theophylline prepared with various concentrations of carnauba wax were sintered thermally at various times and temperatures. In vitro drug release profiles indicated an increase in drug release retardation with increasing carnauba wax concentration. Pellets prepared with ground wax showed a higher standard deviation than did those prepared with emulsified wax. There was incomplete release at the end of 12 hours for pellets prepared with 20% ground or emulsified wax. The sintering temperature and duration were optimized to allow for a sustained release lasting at least 12 hours. The optimized temperature and duration were found to be 100 degrees C and 140 seconds, respectively. The sintered pellets had a higher hydrophobicity than did the unsintered pellets. Scanning electron micrographs indicated that the carnauba wax moved internally, thereby increasing the surface area of wax within the pellets.

  6. A diagnostic wax-up technique.

    PubMed

    Morgan, D W; Comella, M C; Staffanou, R S

    1975-02-01

    A procedural outline has been presented for the accomplishment of a diagnostic wax-up as a preliminary step to actual preparation of the teeth as suggested by the proponents of gnathologic techniques. 8.9) The use of this technique will decrease the possibility of error in the construction of any extensive fixed partial denture prosthesis. The success of any procedure required the willingness of general dentists and specialists to, 'Spend more time planning than doing.'

  7. Hot Wax Sweeps Debris From Narrow Passages

    NASA Technical Reports Server (NTRS)

    Ricklefs, Steven K.

    1990-01-01

    Safe and effective technique for removal of debris and contaminants from narrow passages involves entrainment of undesired material in thermoplastic casting material. Semisolid wax slightly below melting temperature pushed along passage by pressurized nitrogen to remove debris. Devised to clean out fuel passages in main combustion chamber of Space Shuttle main engine. Also applied to narrow, intricate passages in internal-combustion-engine blocks, carburetors, injection molds, and other complicated parts.

  8. Wax deposition in a WAG flood

    SciTech Connect

    Nenninger, J.E.; Cutten, F.B.; Shields, S.N.

    1985-01-01

    Substantial deposits of a gummy material were discovered in the injection system of a water-alternating-gas (WAG) miscible flood. Capillary column gas chromatographic analyses revealed that these deposits were due to wax contamination of the natural gas liquids used to enrich the injection gas. To remove the deposits, propane was added to the injection gas. This treatment was carried out successfully at virtually no extra cost.

  9. Instant freezing of impacting wax drops

    NASA Astrophysics Data System (ADS)

    Ponomarenko, Alexandre; Virot, Emmanuel; Rubinstein, Shmuel

    2015-11-01

    We present the impact of hot liquid drops of wax on surfaces whose temperature is below the solidifying temperature of the drops. During the fall the drops remain mostly liquid, but upon impact, their temperature quickly decreases resulting in the solidification of the drop. Depending on the impact energy, drops size and the temperature difference between the drop and the surface this results in plethora of solid shapes: simple lenses, triangular drops, spherical caps and popped popcorn shapes.

  10. Natural oils and waxes: studies on stick bases.

    PubMed

    Budai, Lívia; Antal, István; Klebovich, Imre; Budai, Marianna

    2012-01-01

    The objective of the present article was to examine the role of origin and quantity of selected natural oils and waxes in the determination of the thermal properties and hardness of stick bases. The natural oils and waxes selected for the study were sunflower, castor, jojoba, and coconut oils. The selected waxes were yellow beeswax, candelilla wax, and carnauba wax. The hardness of the formulations is a critical parameter from the aspect of their application. Hardness was characterized by the measurement of compression strength along with the softening point, the drop point, and differential scanning calorimetry (DSC). It can be concluded that coconut oil, jojoba oil, and carnauba wax have the greatest influence on the thermal parameters of stick bases.

  11. Preparation of tool mark standards with jewelry modeling waxes.

    PubMed

    Petraco, Nicholas; Petraco, Nicholas D K; Faber, Lisa; Pizzola, Peter A

    2009-03-01

    This paper presents how jewelry modeling waxes are used in the preparation of tool mark standards from exemplar tools. We have previously found that jewelry modeling waxes are ideal for preparing test tool marks from exemplar tools. In this study, simple methods and techniques are offered for the replication of accurate, highly detailed tool mark standards with jewelry modeling waxes. The techniques described here demonstrate the conditioning and proper use of jewelry modeling wax in the production of tool mark standards. The application of each test tool's working surface to a piece of the appropriate wax in a manner consistent with the tool's design is clearly illustrated. The resulting tool mark standards are exact, highly detailed, 1:1, negative impressions of the exemplar tool's working surface. These wax models have a long shelf life and are suitable for use in microscopic examination comparison of questioned and known tool marks. PMID:19187458

  12. Petroleomics by EASI(+/-) FT-ICR MS.

    PubMed

    Corilo, Yuri E; Vaz, Boniek G; Simas, Rosineide C; Nascimento, Heliara D Lopes; Klitzke, Clécio F; Pereira, Rosana C L; Bastos, Wagner L; Santos Neto, Eugênio V; Rodgers, Ryan P; Eberlin, Marcos N

    2010-05-15

    An ambient ionization/desorption technique, namely, easy ambient sonic-spray ionization mass spectrometry (EASI), has been applied to crude oil samples. From a single droplet of the sample placed on an inert surface, EASI(+/-) is shown to promote efficient desorption and ionization of a myriad of polar components via the action of its cloud of very minute supersonic bipolar charged droplets. The gaseous [M + H](+) and [M - H](-) ions concurrently formed by EASI(+/-) were analyzed by Fourier transform mass spectrometry (FT-ICR MS), and a total of approximately 6000 acidic and basic components have been attributed. EASI(+/-) FT-ICR MS of crude oils is show to be almost as fast as ESI(+)/ESI(-) FT-ICR MS, providing similar compositional information of polar components and spectral quality comparable to that of a commercial nonochip-based robotic ESI device. EASI(+/-) requires no sample workup thus eliminating risks of contamination during sample manipulation and memory effects because of carry over in pumping ESI lines. More importantly, EASI(+/-) is a voltage-free ionization technique therefore eliminating risks of redox processes or duality of ionization mechanisms that can be observed in voltage-assisted processes. Data visualization via typical petroleomic plots confirms the similarity of the compositional information provided by EASI(+/-) compared to ESI(+)/ESI(-). The ambient EASI(+/-) FT-ICR MS method requires no voltage switching in changing the ion polarity mode, offering a workup, heating and voltage-free protocol for petroleomic studies performed at open atmosphere directly on the undisturbed crude oil sample.

  13. Coking of distallate feed with added paraffin wax

    SciTech Connect

    Mimun, K.; Zaitseva, N.P.; Smidovich, E.V.

    1987-09-01

    The effects of adding paraffin wax to fluid and delayed coking distillates on the yield, microstructure, and physicochemical properties of the cokes were investigated. It was established that by adding optimal amounts of wax to a distillate feed with a high stability factor, the coke yield can be increased by 2.5 to 5.8 percent by weight. The wax should be injected into the feedstock between the furnace and chamber in delayed coking units. The addition of wax to the feed in order to increase the stability factor could be used as a method for reducing tube coking in cracking furnaces.

  14. Absorption and distribution of orally administered jojoba wax in mice.

    PubMed

    Yaron, A; Samoiloff, V; Benzioni, A

    1982-03-01

    The liquid wax obtained from the seeds of the arid-land shrub jojoba (Simmondsia chinensis) is finding increasing use in skin treatment preparations. The fate of this wax upon reaching the digestive tract was studied. 14C-Labeled wax was administered intragastrically to mice, and the distribution of the label in the body was determined as a function of time. Most of the wax was excreted, but a small amount was absorbed, as was indicated by the distribution of label in the internal organs and the epididymal fat. The label was incorporated into the body lipids and was found to diminish with time.

  15. Wax lipids signal nest identity in bumblebee colonies.

    PubMed

    Rottler, Ann-Marie; Schulz, Stefan; Ayasse, Manfred

    2013-01-01

    The signalling functions of cuticular lipids, particularly cuticular hydrocarbons, have gained considerable attention in social insect communication. Information transfer between individuals by means of these substances has been examined extensively. However, communication with cuticular lipids is not limited to inter-individual recognition. Cuticular compounds can also have a signalling function in the nest environment. Workers of the bumblebee Bombus terrestris leave cuticular lipid traces, so-called footprints, that mark their nest entrance. In addition, there is evidence that bumblebees sense nesting material to identify their colony. In this study, we examined the signalling potential of bumblebee wax, and tested if bumblebee workers are able to identify their colony with the help of wax scent. Chemical analyses of wax extracts using coupled gas chromatography-mass spectrometry showed that wax from colonies of the bumblebee B. terrestris contained a complex blend of cuticular lipids, dominated by hydrocarbons and wax esters. Comparing the relative compound amounts of wax samples from different colonies, we found that wax scent patterns varied with nest identity. Olfactometer bioassays showed that bumblebees were able to discriminate between wax scents from their own and a foreign colony. Our findings suggest that wax emits characteristic olfactory profiles that are used by workers to recognize their colony.

  16. Chemical composition of Borislav ozocerite

    SciTech Connect

    Batukova, G.I.; Davydov, V.D.; Shcherbik, L.K.; Petrishchev, K.P.; Kolodko, N.P.; Moiseyeva, A.F.

    1983-01-01

    Ozocerite is a natural wax product with wide commercial use. The absence of comprehensive data concerning the chemical composition and structure of ozocerite hinders the production of wax melts with predetermined properties. Slight changes in the chemical composition of wax products, difficult to detect by modern methods of investigation, have a decisive effect on the properties of these products. Individual compounds have not, so far, been identified by present-day physicochemical methods. This paper describes an investigation of the chemical composition of Borislav ozocerite using a method developed to study the composition of Soviet lignite wax. Borislav ozocerite obtained by extraction with BR-70 light petroleum spirit under industrial conditions and with BR-1 light petroleum spirit, under laboratory conditions (samples A and B, respectively) were examined. Physical and chemical properties of Borislav ozocerite were determined. 6 references, 2 figures, 3 tables.

  17. Noninvasive in situ identification and band assignments of some pharmaceutical excipients inside USP vials with FT-near-infrared spectroscopy.

    PubMed

    Ali, Hassan Refat H; Edwards, Howell G M; Scowen, Ian J

    2009-05-01

    For the manufacture of dosage forms all ingredients must be reliably identified. In this paper, the suitability of FT-NIR spectroscopy to identify potassium sorbate, sodium starch glycollate, calcium ascorbate, calcium carbonate, candelilla wax, maltosextrin, monohydrated and anhydrous lactose inside USP vials was investigated. Differentiation between the anhydrous and monohydrated forms of lactose was found to be possible by studying the regions of the near-infrared spectrum corresponding to the combination and first overtone stretching frequencies of water. The results show unequivocally the potential of FT-NIR spectroscopy for rapid, in situ and non-destructive identification of pharmaceutical excipients. PMID:19153058

  18. Fischer-Tropsch Cobalt Catalyst Activation and Handling Through Wax Enclosure Methods

    NASA Technical Reports Server (NTRS)

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

    2016-01-01

    Fischer-Tropsch (F-T) synthesis is considered a gas to liquid process which converts syn-gas, a gaseous mixture of hydrogen and carbon monoxide, into liquids of various hydrocarbon chain length and product distributions. Cobalt based catalysts are used in F-T synthesis and are the focus of this paper. One key concern with handling cobalt based catalysts is that the active form of catalyst is in a reduced state, metallic cobalt, which oxidizes readily in air. In laboratory experiments, the precursor cobalt oxide catalyst is activated in a fixed bed at 350 ?C then transferred into a continuous stirred tank reactor (CSTR) with inert gas. NASA has developed a process which involves the enclosure of active cobalt catalyst in a wax mold to prevent oxidation during storage and handling. This improved method allows for precise catalyst loading and delivery into a CSTR. Preliminary results indicate similar activity levels in the F-T reaction in comparison to the direct injection method. The work in this paper was supported by the NASA Fundamental Aeronautics Subsonics Fixed Wing Project.

  19. Cloning and Characterization of the WAX2 Gene of Arabidopsis Involved in Cuticle Membrane and Wax Production

    PubMed Central

    Chen, Xinbo; Goodwin, S. Mark; Boroff, Virginia L.; Liu, Xionglun; Jenks, Matthew A.

    2003-01-01

    Insertional mutagenesis of Arabidopsis ecotype C24 was used to identify a novel mutant, designated wax2, that had alterations in both cuticle membrane and cuticular waxes. Arabidopsis mutants with altered cuticle membrane have not been reported previously. Compared with the wild type, the cuticle membrane of wax2 stems weighed 20.2% less, and when viewed using electron microscopy, it was 36.4% thicker, less opaque, and structurally disorganized. The total wax amount on wax2 leaves and stems was reduced by >78% and showed proportional deficiencies in the aldehydes, alkanes, secondary alcohols, and ketones, with increased acids, primary alcohols, and esters. Besides altered cuticle membranes, wax2 displayed postgenital fusion between aerial organs (especially in flower buds), reduced fertility under low humidity, increased epidermal permeability, and a reduction in stomatal index on adaxial and abaxial leaf surfaces. Thus, wax2 reveals a potential role for the cuticle as a suppressor of postgenital fusion and epidermal diffusion and as a mediator of both fertility and the development of epidermal architecture (via effects on stomatal index). The cloned WAX2 gene (verified by three independent allelic insertion mutants with identical phenotypes) codes for a predicted 632–amino acid integral membrane protein with a molecular mass of 72.3 kD and a theoretical pI of 8.78. WAX2 has six transmembrane domains, a His-rich diiron binding region at the N-terminal region, and a large soluble C-terminal domain. The N-terminal portion of WAX2 is homologous with members of the sterol desaturase family, whereas the C terminus of WAX2 is most similar to members of the short-chain dehydrogenase/reductase family. WAX2 has 32% identity to CER1, a protein required for wax production but not for cuticle membrane production. Based on these analyses, we predict that WAX2 has a metabolic function associated with both cuticle membrane and wax synthesis. These studies provide new insight

  20. Simulation of four pure conduction paraffin-wax freezing experiments

    SciTech Connect

    Deal, R.; Solomon, A.D.

    1981-01-01

    Four freezing experiments with N-Octadecane paraffin wax are described. Their results are analyzed using a variety of mathematical techniques for conduction phase-change problems. It is concluded, among other things, that the effective thermal conductivity of the solid wax in this case is about 3.5 times the literature value.

  1. Measuring infiltration during paraffin wax processing for histology.

    PubMed

    Allison, R T; Lloyd, D

    1996-09-01

    A method is described to allow monitoring of the penetration of processing fluids into tissue during histological processing. The method is established by evaluating the effect of incorporating dimethyl sulphoxide into paraffin wax and comparing processing times with those for pure paraffin wax.

  2. Gluconeogenesis from storage wax in the cotyledons of jojoba seedlings.

    PubMed

    Moreau, R A; Huang, A H

    1977-08-01

    The cotyledons of jojoba (Simmondsia chinensis) seeds contained 50 to 60% of their weight as intracellular wax esters. During germination there was a gradual decrease in the wax content with a concomitant rise in soluble carbohydrates, suggesting that the wax played the role of a food reserve. Thin layer chromatography revealed that both the fatty alcohol and fatty acid were metabolized. The disappearance of wax was matched with an increase of catalase, a marker enzyme of the gluconeogenic process in other fatty seedlings. Subcellular organelles were isolated by sucrose gradient centrifugation from the cotyledons at the peak stage of germination. The enzymes of the beta oxidation of fatty acid and of the glyoxylate cycle were localized in the glyoxysomes but not in the mitochondria. The glyoxysomes had specific activities of individual enzymes similar to those of the castor bean glyoxysomes. An active alkaline lipase was detected in the wax bodies at the peak stage of germination but not in the ungerminated seeds. No lipase was detected in glyoxysomes or mitochondria. After the wax in the wax bodies had been extracted with diethyl ether, the organelle membrane was isolated and it still retained the alkaline lipase. The gluconeogenesis from wax in the jojoba seedling appears to be similar, but with modification, to that from triglyceride in other fatty seedlings.

  3. Interspecific utilisation of wax in comb building by honeybees

    NASA Astrophysics Data System (ADS)

    Hepburn, H. Randall; Radloff, Sarah E.; Duangphakdee, Orawan; Phaincharoen, Mananya

    2009-06-01

    Beeswaxes of honeybee species share some homologous neutral lipids; but species-specific differences remain. We analysed behavioural variation for wax choice in honeybees, calculated the Euclidean distances for different beeswaxes and assessed the relationship of Euclidean distances to wax choice. We tested the beeswaxes of Apis mellifera capensis, Apis florea, Apis cerana and Apis dorsata and the plant and mineral waxes Japan, candelilla, bayberry and ozokerite as sheets placed in colonies of A. m. capensis, A. florea and A. cerana. A. m. capensis accepted the four beeswaxes but removed Japan and bayberry wax and ignored candelilla and ozokerite. A. cerana colonies accepted the wax of A. cerana, A. florea and A. dorsata but rejected or ignored that of A. m. capensis, the plant and mineral waxes. A. florea colonies accepted A. cerana, A. dorsata and A. florea wax but rejected that of A. m. capensis. The Euclidean distances for the beeswaxes are consistent with currently prevailing phylogenies for Apis. Despite post-speciation chemical differences in the beeswaxes, they remain largely acceptable interspecifically while the plant and mineral waxes are not chemically close enough to beeswax for their acceptance.

  4. Physical characterization of wax/oil crystalline networks.

    PubMed

    Martini, Silvana; Tan, Chin Yiap; Jana, Sarbojeet

    2015-05-01

    The objective of this research was to evaluate the physical properties of different types of wax/oil systems. Olive (OO), corn (CO), soybean (SBO), sunflower (SFO), safflower (SAFO), and canola (CAO) oils were mixed with sunflower oil wax (SFOW), paraffin wax (PW), and beeswax (BW) at different concentrations (1% to 10%). Results from this study show that the physical properties of wax/oil systems is affected not only by the concentration and type of wax used, but also by the type of oil used. In general, wax/oil systems formulated with SFOW generated crystalline networks with high enthalpies (1 to 22 J/g) and high G' values (2 to 6 × 10(6) Pa) compared with the values obtained for BW and PW. SFOW crystalline networks were characterized by needle-like crystals independently of the wax concentrations and type of oil used. BW crystalline networks, however, were characterized by different crystal morphologies (needle-like or spherulites) depending on the wax concentration and type of oil used. PW samples were characterized by a crystalline network formed by needle- and platelet-like crystals. Enthalpy values of BW and PW samples were similar (0.3 to 20 J/g), but BW samples resulted in significantly higher (P < 0.05) G' values in the 5% and 10% samples with values of 3.9 × 10(6) and 6.1 × 10(5) Pa for 10% BW and PW, respectively.

  5. Statistical Optimization of Sustained Release Venlafaxine HCI Wax Matrix Tablet.

    PubMed

    Bhalekar, M R; Madgulkar, A R; Sheladiya, D D; Kshirsagar, S J; Wable, N D; Desale, S S

    2008-01-01

    The purpose of this research was to prepare a sustained release drug delivery system of venlafaxine hydrochloride by using a wax matrix system. The effects of bees wax and carnauba wax on drug release profile was investigated. A 3(2) full factorial design was applied to systemically optimize the drug release profile. Amounts of carnauba wax (X(1)) and bees wax (X(2)) were selected as independent variables and release after 12 h and time required for 50% (t(50)) drug release were selected as dependent variables. A mathematical model was generated for each response parameter. Both waxes retarded release after 12 h and increases the t(50) but bees wax showed significant influence. The drug release pattern for all the formulation combinations was found to be approaching Peppas kinetic model. Suitable combination of two waxes provided fairly good regulated release profile. The response surfaces and contour plots for each response parameter are presented for further interpretation of the results. The optimum formulations were chosen and their predicted results found to be in close agreement with experimental findings.

  6. Interspecific utilisation of wax in comb building by honeybees.

    PubMed

    Hepburn, H Randall; Radloff, Sarah E; Duangphakdee, Orawan; Phaincharoen, Mananya

    2009-06-01

    Beeswaxes of honeybee species share some homologous neutral lipids; but species-specific differences remain. We analysed behavioural variation for wax choice in honeybees, calculated the Euclidean distances for different beeswaxes and assessed the relationship of Euclidean distances to wax choice. We tested the beeswaxes of Apis mellifera capensis, Apis florea, Apis cerana and Apis dorsata and the plant and mineral waxes Japan, candelilla, bayberry and ozokerite as sheets placed in colonies of A. m. capensis, A. florea and A. cerana. A. m. capensis accepted the four beeswaxes but removed Japan and bayberry wax and ignored candelilla and ozokerite. A. cerana colonies accepted the wax of A. cerana, A. florea and A. dorsata but rejected or ignored that of A. m. capensis, the plant and mineral waxes. A. florea colonies accepted A. cerana, A. dorsata and A. florea wax but rejected that of A. m. capensis. The Euclidean distances for the beeswaxes are consistent with currently prevailing phylogenies for Apis. Despite post-speciation chemical differences in the beeswaxes, they remain largely acceptable interspecifically while the plant and mineral waxes are not chemically close enough to beeswax for their acceptance.

  7. Physical characterization of wax/oil crystalline networks.

    PubMed

    Martini, Silvana; Tan, Chin Yiap; Jana, Sarbojeet

    2015-05-01

    The objective of this research was to evaluate the physical properties of different types of wax/oil systems. Olive (OO), corn (CO), soybean (SBO), sunflower (SFO), safflower (SAFO), and canola (CAO) oils were mixed with sunflower oil wax (SFOW), paraffin wax (PW), and beeswax (BW) at different concentrations (1% to 10%). Results from this study show that the physical properties of wax/oil systems is affected not only by the concentration and type of wax used, but also by the type of oil used. In general, wax/oil systems formulated with SFOW generated crystalline networks with high enthalpies (1 to 22 J/g) and high G' values (2 to 6 × 10(6) Pa) compared with the values obtained for BW and PW. SFOW crystalline networks were characterized by needle-like crystals independently of the wax concentrations and type of oil used. BW crystalline networks, however, were characterized by different crystal morphologies (needle-like or spherulites) depending on the wax concentration and type of oil used. PW samples were characterized by a crystalline network formed by needle- and platelet-like crystals. Enthalpy values of BW and PW samples were similar (0.3 to 20 J/g), but BW samples resulted in significantly higher (P < 0.05) G' values in the 5% and 10% samples with values of 3.9 × 10(6) and 6.1 × 10(5) Pa for 10% BW and PW, respectively. PMID:25850679

  8. Crystal morphology of sunflower wax in soybean oil organogel

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While sunflower wax has been recognized as an excellent organogelator for edible oil, the detailed morphology of sunflower wax crystals formed in an edible oil organogel has not been fully understood. In this study, polarized light microscopy, phase contrast microscopy, scanning electron microscopy ...

  9. Process for upgrading wax from Fischer-Tropsch synthesis

    DOEpatents

    Derr, Jr., W. Rodman; Garwood, William E.; Kuo, James C.; Leib, Tiberiu M.; Nace, Donald M.; Tabak, Samuel A.

    1987-01-01

    The waxy liquid phase of an oil suspension of Fischer-Tropsch catalyst containing dissolved wax is separated out and the wax is converted by hydrocracking, dewaxing or by catalytic cracking with a low activity catalyst to provide a highly olefinic product which may be further converted to premium quality gasoline and/or distillate fuel.

  10. Process for upgrading wax from Fischer-Tropsch synthesis

    DOEpatents

    Derr, W.R. Jr.; Garwood, W.E.; Kuo, J.C.; Leib, T.M.; Nace, D.M.; Tabak, S.A.

    1987-08-04

    The waxy liquid phase of an oil suspension of Fischer-Tropsch catalyst containing dissolved wax is separated out and the wax is converted by hydrocracking, dewaxing or by catalytic cracking with a low activity catalyst to provide a highly olefinic product which may be further converted to premium quality gasoline and/or distillate fuel. 2 figs.

  11. Advances in handheld FT-IR instrumentation

    NASA Astrophysics Data System (ADS)

    Arnó, Josep; Cardillo, Len; Judge, Kevin; Frayer, Maxim; Frunzi, Michael; Hetherington, Paul; Levy, Dustin; Oberndorfer, Kyle; Perec, Walter; Sauer, Terry; Stein, John; Zuidema, Eric

    2012-06-01

    FT-IR spectroscopy is the technology of choice to identify solid and liquid phase unknown samples. The challenges of ConOps (Concepts of Operation) in emergency response and military field applications require a significant redesign of the stationary FT-IR bench-top instruments typically used in laboratories. Specifically, field portable units require high levels of resistance against mechanical shock and chemical attack, ease of use in restrictive gear, quick and easy interpretation of results, and reduced size. In the last 20 years, FT-IR instruments have been re-engineered to fit in small suitcases for field portable use and recently further miniaturized for handheld operation. This article introduces the advances resulting from a project designed to overcome the challenges associated with miniaturizing FT-IR instruments. The project team developed a disturbance-corrected permanently aligned cube corner interferometer for improved robustness and optimized opto-mechanical design to maximize optical throughput and signal-to-noise ratios. Thermal management and heat flow were thoroughly modeled and studied to isolate sensitive components from heat sources and provide the widest temperature operation range. Similarly, extensive research on mechanical designs and compensation techniques to protect against shock and vibration will be discussed. A user interface was carefully created for military and emergency response applications to provide actionable information in a visual, intuitive format. Similar to the HazMatID family of products, state-of-the-art algorithms were used to quickly identify the chemical composition of complex samples based on the spectral information. This article includes an overview of the design considerations, tests results, and performance validation of the mechanical ruggedness, spectral, and thermal performance.

  12. Effects of aridity and vegetation on plant-wax δD in modern lake sediments

    NASA Astrophysics Data System (ADS)

    Polissar, Pratigya J.; Freeman, Katherine H.

    2010-10-01

    We analyzed the deuterium composition of individual plant-waxes in lake sediments from 28 watersheds that span a range of precipitation D/H, vegetation types and climates. The apparent isotopic fractionation ( ɛa) between plant-wax n-alkanes and precipitation differs with watershed ecosystem type and structure, and decreases with increasing regional aridity as measured by enrichment of 2H and 18O associated with evaporation of lake waters. The most negative ɛa values represent signatures least affected by aridity; these values were -125 ± 5‰ for tropical evergreen and dry forests, -130‰ for a temperate broadleaf forest, -120 ± 9‰ for the high-altitude tropical páramo (herbs, shrubs and grasses), and -98 ± 6‰ for North American montane gymnosperm forests. Minimum ɛa values reflect ecosystem-dependent differences in leaf water enrichment and soil evaporation. Slopes of lipid/lake water isotopic enrichments differ slightly with ecosystem structure (i.e. open shrublands versus forests) and overall are quite small (slopes = 0-2), indicating low sensitivity of lipid δD variations to aridity compared with coexisting lake waters. This finding provides an approach for reconstructing ancient precipitation signatures based on plant-wax δD measurements and independent proxies for lake water changes with regional aridity. To illustrate this approach, we employ paired plant-wax δD and carbonate-δ 18O measurements on lake sediments to estimate the isotopic composition of Miocene precipitation on the Tibetan plateau.

  13. Self‐Replenishable Anti‐Waxing Organogel Materials†

    PubMed Central

    Yao, Xi; Wu, Shuwang; Chen, Lie; Ju, Jie; Gu, Zhandong; Liu, Mingjie; Jiang, Lei

    2015-01-01

    Abstract Solid deposition, such as the formation of ice on outdoor facilities, the deposition of scale in water reservoirs, the sedimentation of fat, oil, and grease (FOG) in sewer systems, and the precipitation of wax in petroleum pipelines, cause a serious waste of resources and irreversible environmental pollution. Inspired by fish and pitcher plants, we present a self‐replenishable organogel material which shows ultra‐low adhesion to solidified paraffin wax and crude oil by absorption of low‐molar‐mass oil from its crude‐oil environment. Adhesion of wax on the organogel surface was over 500 times lower than adhesion to conventional material surfaces and the wax was found to slide off under the force of gravity. This design concept of a gel with decreased adhesion to wax and oil can be extended to deal with other solid deposition problems. PMID:26083324

  14. Toward in vivo chemical imaging of epicuticular waxes.

    PubMed

    Weissflog, Ina; Vogler, Nadine; Akimov, Denis; Dellith, Andrea; Schachtschabel, Doreen; Svatos, Ales; Boland, Wilhelm; Dietzek, Benjamin; Popp, Jürgen

    2010-10-01

    Epicuticular waxes, which are found on the outer surface of plant cuticles, are difficult to study in vivo. To monitor the growth, development, and structural alterations of epicuticular wax layers, coherent anti-Stokes Raman scattering (CARS) might be used. CARS, as a Raman-based technique, not only provides structural insight but also chemical information by imaging the spatial distribution of Raman-active vibrations. Here, we present a comparative study using CARS and scanning electron microscopy to characterize the structure of epicuticular waxes. The ability of CARS to provide detailed structural information on the biologically important wax layer was detailed on the examples of cherry laurel (Prunus laurocerasus), hoya (Hoya carnosa), and ceriman/Swiss cheese plant (Monstera sp. aff. deliciosa). We anticipate that the work presented will open a doorway for online monitoring of formation and alterations of epicuticular wax layers.

  15. Toward in Vivo Chemical Imaging of Epicuticular Waxes1[C

    PubMed Central

    Weissflog, Ina; Vogler, Nadine; Akimov, Denis; Dellith, Andrea; Schachtschabel, Doreen; Svatos, Ales; Boland, Wilhelm; Dietzek, Benjamin; Popp, Jürgen

    2010-01-01

    Epicuticular waxes, which are found on the outer surface of plant cuticles, are difficult to study in vivo. To monitor the growth, development, and structural alterations of epicuticular wax layers, coherent anti-Stokes Raman scattering (CARS) might be used. CARS, as a Raman-based technique, not only provides structural insight but also chemical information by imaging the spatial distribution of Raman-active vibrations. Here, we present a comparative study using CARS and scanning electron microscopy to characterize the structure of epicuticular waxes. The ability of CARS to provide detailed structural information on the biologically important wax layer was detailed on the examples of cherry laurel (Prunus laurocerasus), hoya (Hoya carnosa), and ceriman/Swiss cheese plant (Monstera sp. aff. deliciosa). We anticipate that the work presented will open a doorway for online monitoring of formation and alterations of epicuticular wax layers. PMID:20709828

  16. Thermostimulable wax@SiO2 core-shell particles.

    PubMed

    Destribats, Mathieu; Schmitt, Véronique; Backov, Rénal

    2010-02-01

    We propose a new synthesis pathway without any sacrificial template to prepare original monodisperse thermoresponsive capsules made of a wax core surrounded by a silica shell. Under heating, the inner wax expands and the shell breaks, leading to the liquid oil release. Such capsules that allow triggered deliverance provoked by an external stimulus belong to the class of smart materials. The process is based on the elaboration of size-controlled emulsions stabilized by particles (Pickering emulsions) exploiting the limited coalescence phenomenon. Then the emulsions are cooled down and the obtained suspensions are mineralized by the hydrolysis and condensation of a monomer at the wax-water interface, leading to the formation of capsules. The shell break and the liquid oil release are provoked by heating above the wax melting temperature. We characterize the obtained materials and examine the effect of processing parameters and heating history. By an appropriate choice of the wax, the temperature of release can easily be tuned. PMID:20099917

  17. Pickering emulsions stabilized by paraffin wax and Laponite clay particles.

    PubMed

    Li, Caifu; Liu, Qian; Mei, Zhen; Wang, Jun; Xu, Jian; Sun, Dejun

    2009-08-01

    Emulsions containing wax in dispersed droplets stabilized by disc-like Laponite clay particles are prepared. Properties of the emulsions prepared at different temperatures are examined using stability, microscopy and droplet-size analysis. At low temperature, the wax crystals in the oil droplets can protrude through the interface, leading to droplet coalescence. But at higher temperatures, the droplet size decreases with wax concentration. Considering the viscosity of the oil phase and the interfacial tension, we conclude that the wax is liquid-like during the high temperature emulsification process, but during cooling wax crystals appear around the oil/water interface and stabilize the droplets. The oil/water ratio has minimal effect on the emulsions between ratios of 3:7 and 7:3. The Laponite is believed to stabilize the emulsions by increasing the viscosity of the continuous phase and also by adsorbing at the oil/water interface, thus providing a physical barrier to coalescence. PMID:19428022

  18. Advantages of catalytically de-waxed lubricant base oils

    SciTech Connect

    Schoonmaker, J.P.; Stiponavic, A.J.

    1996-10-01

    The production of base oils used in the formulation of lubricants involves the vacuum distillation of crude oil followed by a series of processing steps that improve physical and chemical properties including viscosity index and oxidative stability. An important stage in this process is the removal of linear parafins (wax) from the base oil which can crystalize causing poor flow properties at low temperatures. {open_quotes}De-waxing{close_quotes} may be accomplished using a solvent precipitation batch process (solvent de-waxing: SDW) or through a more modern continuous catalytic process (catalytic de-waxing: CDW) which offers many advantages. In general, catalytically de-waxed base oils exhibit improved low temperature fluidity which provides enhanced performance for transmission fluids and other lubricants required to operate efficiently at temperature reaching -40{degrees}C. A discussion of the molecular mechanisms involved in CDW and results of viscometric testing at low temperatures will be presented.

  19. Thermostimulable wax@SiO2 core-shell particles.

    PubMed

    Destribats, Mathieu; Schmitt, Véronique; Backov, Rénal

    2010-02-01

    We propose a new synthesis pathway without any sacrificial template to prepare original monodisperse thermoresponsive capsules made of a wax core surrounded by a silica shell. Under heating, the inner wax expands and the shell breaks, leading to the liquid oil release. Such capsules that allow triggered deliverance provoked by an external stimulus belong to the class of smart materials. The process is based on the elaboration of size-controlled emulsions stabilized by particles (Pickering emulsions) exploiting the limited coalescence phenomenon. Then the emulsions are cooled down and the obtained suspensions are mineralized by the hydrolysis and condensation of a monomer at the wax-water interface, leading to the formation of capsules. The shell break and the liquid oil release are provoked by heating above the wax melting temperature. We characterize the obtained materials and examine the effect of processing parameters and heating history. By an appropriate choice of the wax, the temperature of release can easily be tuned.

  20. Pickering emulsions stabilized by paraffin wax and Laponite clay particles.

    PubMed

    Li, Caifu; Liu, Qian; Mei, Zhen; Wang, Jun; Xu, Jian; Sun, Dejun

    2009-08-01

    Emulsions containing wax in dispersed droplets stabilized by disc-like Laponite clay particles are prepared. Properties of the emulsions prepared at different temperatures are examined using stability, microscopy and droplet-size analysis. At low temperature, the wax crystals in the oil droplets can protrude through the interface, leading to droplet coalescence. But at higher temperatures, the droplet size decreases with wax concentration. Considering the viscosity of the oil phase and the interfacial tension, we conclude that the wax is liquid-like during the high temperature emulsification process, but during cooling wax crystals appear around the oil/water interface and stabilize the droplets. The oil/water ratio has minimal effect on the emulsions between ratios of 3:7 and 7:3. The Laponite is believed to stabilize the emulsions by increasing the viscosity of the continuous phase and also by adsorbing at the oil/water interface, thus providing a physical barrier to coalescence.

  1. [Nondestructive discrimination of waxed apples based on hyperspectral imaging technology].

    PubMed

    Gao, Jun-Feng; Zhang, Hai-Liang; Kong, Wen-Wen; He, Yong

    2013-07-01

    The potential of hyperspectral imaging technology was evaluated for discriminating three types of waxed apples. Three types of apples smeared with fruit wax, with industrial wax, and not waxed respectively were imaged by a hyperspectral imaging system with a spectral range of 308-1 024 nm. ENVI software processing platform was used for extracting hyperspectral image object of diffuse reflection spectral response characteristics. Eighty four of 126 apple samples were selected randomly as calibration set and the rest were prediction set. After different preprocess, the related mathematical models were established by using the partial least squares (PLS), the least squares support vector machine (LS-SVM) and BP neural network methods and so on. The results showed that the model of MSC-SPA-LSSVM was the best to discriminate three kinds of waxed apples with 100%, 100% and 92.86% correct prediction respectively.

  2. Wax perception in honeybees: contact is not necessary.

    PubMed

    Brockmann, Axel; Groh, Claudia; Fröhlich, Birgit

    2003-09-01

    In social insects, much progress has been made in identifying variations in the cuticular signatures of sexes, castes, kin and reproductive status. In contrast to this, we still do not know how the receivers perceive these recognition cues. This study was designed to investigate whether honeybees use contact-chemosensory or olfactory sensilla to perceive wax components. To answer this question in a behavioral assay, we combined classical conditioning of the proboscis extension reaction and a recently established method using zinc sulfate to selectively block antennal contact-chemosensory sensilla. Comparison of the responses to sucrose, wax and geraniol before and after antennal zinc sulfate treatment revealed that the sucrose response is lost after treatment but the responses to wax and geraniol are maintained. As sucrose is perceived by the contact-chemosensory sensilla, the retention of the wax response indicates that contact-chemosensory sensilla are not necessary for wax perception.

  3. Self-Replenishable Anti-Waxing Organogel Materials.

    PubMed

    Yao, Xi; Wu, Shuwang; Chen, Lie; Ju, Jie; Gu, Zhandong; Liu, Mingjie; Wang, Jianjun; Jiang, Lei

    2015-07-27

    Solid deposition, such as the formation of ice on outdoor facilities, the deposition of scale in water reservoirs, the sedimentation of fat, oil, and grease (FOG) in sewer systems, and the precipitation of wax in petroleum pipelines, cause a serious waste of resources and irreversible environmental pollution. Inspired by fish and pitcher plants, we present a self-replenishable organogel material which shows ultra-low adhesion to solidified paraffin wax and crude oil by absorption of low-molar-mass oil from its crude-oil environment. Adhesion of wax on the organogel surface was over 500 times lower than adhesion to conventional material surfaces and the wax was found to slide off under the force of gravity. This design concept of a gel with decreased adhesion to wax and oil can be extended to deal with other solid deposition problems. PMID:26083324

  4. SEPARATION OF FISCHER-TROPSCH WAX FROM CATALYST BY SUPERCRITICAL EXTRACTION

    SciTech Connect

    Patrick C. Joyce; Mark C. Thies

    1999-03-31

    The objective of this research project was to evaluate the potential of supercritical fluid (SCF) extraction for the recovery and fractionation of the wax product from the slurry bubble column (SBC) reactor of the Fischer-Tropsch (F-T) process. The wax, comprised mostly of branched and linear alkanes with a broad molecular weight distribution up to C{sub 100}, is to be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300 C. Aspen Plus{trademark} was used to perform process simulation studies on the proposed extraction process, with Redlich-Kwong-Soave (RKS) being used for the thermodynamic property model. In summary, we have made comprehensive VLE measurements for short alkane + long alkane systems over a wide range of pressures and temperatures, dramatically increasing the amount of high-quality data available for these simple, yet highly relevant systems. In addition, our work has demonstrated that, surprisingly, no current thermodynamic model can adequately predict VLE behavior for these systems. Thus, process simulations (such as those for our proposed SCF extraction process) that incorporate these systems can currently only give results that are qualitative at best. Although significant progress has been made in the past decade, more experimental and theoretical work remain to be done before the phase equilibria of asymmetric alkane mixtures can be predicted with confidence.

  5. Detailed characterization of the substrate specificity of mouse wax synthase.

    PubMed

    Miklaszewska, Magdalena; Kawiński, Adam; Banaś, Antoni

    2013-01-01

    Wax synthases are membrane-associated enzymes catalysing the esterification reaction between fatty acyl-CoA and a long chain fatty alcohol. In living organisms, wax esters function as storage materials or provide protection against harmful environmental influences. In industry, they are used as ingredients for the production of lubricants, pharmaceuticals, and cosmetics. Currently the biological sources of wax esters are limited to jojoba oil. In order to establish a large-scale production of desired wax esters in transgenic high-yielding oilseed plants, enzymes involved in wax esters synthesis from different biological resources should be characterized in detail taking into consideration their substrate specificity. Therefore, this study aims at determining the substrate specificity of one of such enzymes -- the mouse wax synthase. The gene encoding this enzyme was expressed heterologously in Saccharomyces cerevisiae. In the in vitro assays (using microsomal fraction from transgenic yeast), we evaluated the preferences of mouse wax synthase towards a set of combinations of 11 acyl-CoAs with 17 fatty alcohols. The highest activity was observed for 14:0-CoA, 12:0-CoA, and 16:0-CoA in combination with medium chain alcohols (up to 5.2, 3.4, and 3.3 nmol wax esters/min/mg microsomal protein, respectively). Unsaturated alcohols longer than 18°C were better utilized by the enzyme in comparison to the saturated ones. Combinations of all tested alcohols with 20:0-CoA, 22:1-CoA, or Ric-CoA were poorly utilized by the enzyme, and conjugated acyl-CoAs were not utilized at all. Apart from the wax synthase activity, mouse wax synthase also exhibited a very low acyl-CoA:diacylglycerol acyltransferase activity. However, it displayed neither acyl-CoA:monoacylglycerol acyltransferase, nor acyl-CoA:sterol acyltransferase activity.

  6. Multiple plant-wax compounds record differential sources and ecosystem structure in large river catchments

    NASA Astrophysics Data System (ADS)

    Hemingway, Jordon D.; Schefuß, Enno; Dinga, Bienvenu Jean; Pryer, Helena; Galy, Valier V.

    2016-07-01

    The concentrations, distributions, and stable carbon isotopes (δ13C) of plant waxes carried by fluvial suspended sediments contain valuable information about terrestrial ecosystem characteristics. To properly interpret past changes recorded in sedimentary archives it is crucial to understand the sources and variability of exported plant waxes in modern systems on seasonal to inter-annual timescales. To determine such variability, we present concentrations and δ13C compositions of three compound classes (n-alkanes, n-alcohols, n-alkanoic acids) in a 34-month time series of suspended sediments from the outflow of the Congo River. We show that exported plant-dominated n-alkanes (C25-C35) represent a mixture of C3 and C4 end members, each with distinct molecular distributions, as evidenced by an 8.1 ± 0.7‰ (±1σ standard deviation) spread in δ13C values across chain-lengths, and weak correlations between individual homologue concentrations (r = 0.52-0.94). In contrast, plant-dominated n-alcohols (C26-C36) and n-alkanoic acids (C26-C36) exhibit stronger positive correlations (r = 0.70-0.99) between homologue concentrations and depleted δ13C values (individual homologues average ⩽-31.3‰ and -30.8‰, respectively), with lower δ13C variability across chain-lengths (2.6 ± 0.6‰ and 2.0 ± 1.1‰, respectively). All individual plant-wax lipids show little temporal δ13C variability throughout the time-series (1σ ⩽ 0.9‰), indicating that their stable carbon isotopes are not a sensitive tracer for temporal changes in plant-wax source in the Congo basin on seasonal to inter-annual timescales. Carbon-normalized concentrations and relative abundances of n-alcohols (19-58% of total plant-wax lipids) and n-alkanoic acids (26-76%) respond rapidly to seasonal changes in runoff, indicating that they are mostly derived from a recently entrained local source. In contrast, a lack of correlation with discharge and low, stable relative abundances (5-16%) indicate that

  7. Wax control in oil wells using a thermal syphon system

    SciTech Connect

    Hall, E.N.

    1982-05-11

    This invention relates to a system for controlling wax formation in oil wells using a thermal syphon wherein a confined annular space between the production tube and the oil string casing is provided by means of a plug, or ''packer'', installed at a point well below the level at which solid waxes begin to deposit out of the exiting crude oil and a plug, or ''packer'', installed above the point at which waxes would otherwise stop depositing out of the exiting crude oil and thereafter filling the confined annulus with a fluid working medium. The quantity and properties of the fluid working medium are arranged such that the medium is vaporized at the lower extremeties of the confined annulus and condensed on the surfaces of the upper regions of the confined annulus, particularly in the zone of wax deposition. The condensation process warms the production tube sufficiently to prevent formation of adhesive wax deposits or, alternatively, reliquifies a thin film of deposited wax which enables the flowing crude oil to remove the deposited wax. The condensed working medium flows by gravity to the lower part of the confined annulus where it again becomes available for vaporization and subsequent condensation. No external power is used for this circulation which is caused solely by temperature differences between lower and higher levels of the annulus.

  8. WAXS studies of the structural diversity of hemoglobin in solution.

    SciTech Connect

    Makowski, L.; Bardhan, J.; Gore, D.; Lal, J.; Mandava, S.; Park, S.; Rodi, D. J.; Ho, N. T.; Ho, C.; Fischetti, R. F.

    2011-01-01

    Specific ligation states of hemoglobin are, when crystallized, capable of taking on multiple quaternary structures. The relationship between these structures, captured in crystal lattices, and hemoglobin structure in solution remains uncertain. Wide-angle X-ray solution scattering (WAXS) is a sensitive probe of protein structure in solution that can distinguish among similar structures and has the potential to contribute to these issues. We used WAXS to assess the relationships among the structures of human and bovine hemoglobins in different liganded forms in solution. WAXS data readily distinguished among the various forms of hemoglobins. WAXS patterns confirm some of the relationships among hemoglobin structures that have been defined through crystallography and NMR and extend others. For instance, methemoglobin A in solution is, as expected, nearly indistinguishable from HbCO A. Interestingly, for bovine hemoglobin, the differences between deoxy-Hb, methemoglobin and HbCO are smaller than the corresponding differences in human hemoglobin. WAXS data were also used to assess the spatial extent of structural fluctuations of various hemoglobins in solution. Dynamics has been implicated in allosteric control of hemoglobin, and increased dynamics has been associated with lowered oxygen affinity. Consistent with that notion, WAXS patterns indicate that deoxy-Hb A exhibits substantially larger structural fluctuations than HbCO A. Comparisons between the observed WAXS patterns and those predicted on the basis of atomic coordinate sets suggest that the structures of Hb in different liganded forms exhibit clear differences from known crystal structure.

  9. Illustrations of the anatomical wax model collection in the "La Specola" Zoology Museum, Florence.

    PubMed

    Lotti, S; Altobelli, A; Bambi, S; Poggesi, M

    2006-01-01

    Anatomical illustration has evolved through the centuries, first having artistic and educational purposes and later more strictly medical objectives. Between the eleventh and fifteenth centuries, the analytical model (representation of individual parts, organs and systems) gave way to the composite model (description of the human body as a whole). Between the seventeenth and eighteenth centuries, there was a reversal of tendency: initially the anatomist requested the help of artists, but later the artist asked anatomists to check the accuracy of his work. In this way, anatomical illustration reached a high level of precision. This period also saw the creation of the "La Specola" Zoology Museum's collection of anatomical wax models. Initiated in the eighteenth century, it also included a series of contemporary colour illustrations executed by various artists. Most of the illustrations concern human anatomy, while a small number deal with comparative anatomy. These illustrations, each accompanied by one or more explanatory sheets, were produced to help explain the corresponding wax models. The anatomical wax model collection has been well preserved through the centuries, maintaining its ancient splendour, and it is the object of continuing research and restoration interventions.

  10. Effects of temperature on water-in-oil emulsions stabilised solely by wax microparticles.

    PubMed

    Binks, Bernard P; Rocher, Anaïs

    2009-07-01

    The possibility of stabilising oil-water mixtures using wax particles alone is reported. As judged from contact angle measurements, wax particles are hydrophobic and act as effective emulsifiers of water-in-squalane emulsions. Specific differences exist depending on the chemical composition of the particles. The effect of temperature on emulsion stability has been explored in detail. If particles are pre-adsorbed to water drop interfaces by emulsification at room temperature, subsequent increase of temperature leads to a progressive increase in sedimentation and coalescence as particles melt and desorb from interfaces. The temperature range over which this occurs is similar to that of the melting range of the particles alone. If however the particles are melted prior to emulsification, surface-active long chain ester or acid molecules adsorb to freshly created interfaces giving rise to excellent stability to coalescence at high temperatures. Rapid cooling of these latter emulsions enhances their long-term stability as solidification of the molten wax leads to a thickening of the continuous oil phase. PMID:19406414

  11. Effects of temperature on water-in-oil emulsions stabilised solely by wax microparticles.

    PubMed

    Binks, Bernard P; Rocher, Anaïs

    2009-07-01

    The possibility of stabilising oil-water mixtures using wax particles alone is reported. As judged from contact angle measurements, wax particles are hydrophobic and act as effective emulsifiers of water-in-squalane emulsions. Specific differences exist depending on the chemical composition of the particles. The effect of temperature on emulsion stability has been explored in detail. If particles are pre-adsorbed to water drop interfaces by emulsification at room temperature, subsequent increase of temperature leads to a progressive increase in sedimentation and coalescence as particles melt and desorb from interfaces. The temperature range over which this occurs is similar to that of the melting range of the particles alone. If however the particles are melted prior to emulsification, surface-active long chain ester or acid molecules adsorb to freshly created interfaces giving rise to excellent stability to coalescence at high temperatures. Rapid cooling of these latter emulsions enhances their long-term stability as solidification of the molten wax leads to a thickening of the continuous oil phase.

  12. 21 CFR 155.120 - Canned green beans and canned wax beans.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Vegetables § 155.120 Canned green beans and canned wax beans. (a) Identity—(1) Definition. Canned green beans and canned wax beans are the foods prepared from succulent pods of fresh green bean or wax bean plants... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Canned green beans and canned wax beans....

  13. 21 CFR 155.120 - Canned green beans and canned wax beans.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Vegetables § 155.120 Canned green beans and canned wax beans. (a) Identity—(1) Definition. Canned green beans and canned wax beans are the foods prepared from succulent pods of fresh green bean or wax bean plants... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Canned green beans and canned wax beans....

  14. 21 CFR 155.120 - Canned green beans and canned wax beans.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Vegetables § 155.120 Canned green beans and canned wax beans. (a) Identity—(1) Definition. Canned green beans and canned wax beans are the foods prepared from succulent pods of fresh green bean or wax bean plants... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Canned green beans and canned wax beans....

  15. 21 CFR 155.120 - Canned green beans and canned wax beans.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Vegetables § 155.120 Canned green beans and canned wax beans. (a) Identity—(1) Definition. Canned green beans and canned wax beans are the foods prepared from succulent pods of fresh green bean or wax bean plants... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Canned green beans and canned wax beans....

  16. 21 CFR 155.120 - Canned green beans and canned wax beans.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Vegetables § 155.120 Canned green beans and canned wax beans. (a) Identity—(1) Definition. Canned green beans and canned wax beans are the foods prepared from succulent pods of fresh green bean or wax bean plants... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Canned green beans and canned wax beans....

  17. Quantitative trait loci controlling amounts and types of epicuticular waxes in onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural variation exists in onion (Allium cepa L.) for amounts and types of epicuticular waxes on leaves. Wild-type waxy onion possesses copious amounts of these waxes, while the foliage of semi-glossy and glossy phenotypes accumulate significantly less wax. Reduced amounts of epicuticular waxes hav...

  18. Properties of cookies made with natural wax-vegetable oil organogels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organogels prepared with a natural wax and a vegetable oil were examined as alternatives to a commercial margarine in cookie. To investigate effects of wax and vegetable oil on properties of cookie dough and cookies, organogels prepared from four different waxes including sunflower wax, rice bran wa...

  19. Analysis of aliphatic waxes associated with root periderm or exodermis from eleven plant species.

    PubMed

    Kosma, Dylan K; Rice, Adam; Pollard, Mike

    2015-09-01

    Aliphatic waxes can be found in association with suberized tissues, including roots. Non-polar lipids were isolated by rapid solvent extraction of mature regions of intact roots from eleven angiosperms, including both monocots and dicots. The majority of roots analyzed were taproots or tuberous taproots that had undergone secondary growth and thus were covered by a suberized periderm. The exceptions therein were maize (Zea mays L.) and rice (Oryza sativa L.), which present a suberized exodermis. The analysis herein focused on aliphatic waxes, with particular emphasis on alkyl hydroxycinnamates (AHCs). AHCs were widely distributed, absent from only one species, were found in both aerial and subterranean portions of tuberous taproots, and were associated with the fibrous roots of both maize and rice. Most species also contained monoacylglycerols, fatty alcohols and/or free fatty acids. Carrot (Daucus carrota L.) was the outlier, containing only free fatty acids, sterols, and polyacetylenes as identified components. Sterols were the only ubiquitous component across all roots analyzed. Monoacylglycerols of ω-hydroxy fatty acids were present in maize and rice root waxes. For species within the Brassiceae, wax compositions varied between subspecies or varieties and between aerial and subterranean portions of taproots. In addition, reduced forms of photo-oxidation products of ω-hydroxy oleate and its corresponding dicarboxylic acid (10,18-dihydroxy-octadec-8-enoate, 9,18-dihydroxy-octadec-10-enoate and 9-hydroxyoctadec-10-ene-1,18-dioate) were identified as naturally occurring suberin monomers in rutabaga (Brassica napus subsp. rapifera Metzg.) periderm tissues.

  20. Analysis of aliphatic waxes associated with root periderm or exodermis from eleven plant species.

    PubMed

    Kosma, Dylan K; Rice, Adam; Pollard, Mike

    2015-09-01

    Aliphatic waxes can be found in association with suberized tissues, including roots. Non-polar lipids were isolated by rapid solvent extraction of mature regions of intact roots from eleven angiosperms, including both monocots and dicots. The majority of roots analyzed were taproots or tuberous taproots that had undergone secondary growth and thus were covered by a suberized periderm. The exceptions therein were maize (Zea mays L.) and rice (Oryza sativa L.), which present a suberized exodermis. The analysis herein focused on aliphatic waxes, with particular emphasis on alkyl hydroxycinnamates (AHCs). AHCs were widely distributed, absent from only one species, were found in both aerial and subterranean portions of tuberous taproots, and were associated with the fibrous roots of both maize and rice. Most species also contained monoacylglycerols, fatty alcohols and/or free fatty acids. Carrot (Daucus carrota L.) was the outlier, containing only free fatty acids, sterols, and polyacetylenes as identified components. Sterols were the only ubiquitous component across all roots analyzed. Monoacylglycerols of ω-hydroxy fatty acids were present in maize and rice root waxes. For species within the Brassiceae, wax compositions varied between subspecies or varieties and between aerial and subterranean portions of taproots. In addition, reduced forms of photo-oxidation products of ω-hydroxy oleate and its corresponding dicarboxylic acid (10,18-dihydroxy-octadec-8-enoate, 9,18-dihydroxy-octadec-10-enoate and 9-hydroxyoctadec-10-ene-1,18-dioate) were identified as naturally occurring suberin monomers in rutabaga (Brassica napus subsp. rapifera Metzg.) periderm tissues. PMID:26143051

  1. Diesel fuel containing wax oxidates to reduce particulate emissions

    SciTech Connect

    Sprague, H.G.; Sweeney, W.M.

    1980-09-16

    Addition of 0.1 to 1.5 percent by weight of wax oxidates to a diesel fuel is found to reduce the amount of soot and invisible particles produced when the fuel is used in a diesel engine. The wax oxidates act synergistically with fuel-soluble organometallic compounds such as alkyl cyclopentadienyl manganese tricarbonyl complex salts in reducing particulates. The wax oxidates used have a ratio of neutralization number to saponification number below about 0.40 and a saybolt universal viscosity at 210* F. Higher than 1600.

  2. Methyl isobutyl ketone as a solvent for wax deoiling

    SciTech Connect

    Larikov, V.I.; Pereverzev, A.N.; Roshchin, Y.N.; Sokolova, S.P.

    1983-09-01

    The solvency of methyl isobutyl ketone (MIBK) for use in deoiling and cold-fractionation of solid paraffin waxes is investigated by a visual polytherm method in the temperature interval 0-36 C. The capability of MIBK for precipitating solid hydrocarbons from solution was found to be greater than acetone/toluene or MEK/toluene, with only MEK better in this respect than MIBK. The quantity of wax remaining in the filtrate is examined. The critical solution temperatures are investigated and it is shown that MIBK surpasses MEK. The results obtained indicate that MIBK is extremely promising for use in processes of deoiling and cold fractionation of waxes.

  3. WAX ActiveLibrary: a tool to manage information overload.

    PubMed

    Hanka, R; O'Brien, C; Heathfield, H; Buchan, I E

    1999-11-01

    WAX Active-Library (Cambridge Centre for Clinical Informatics) is a knowledge management system that seeks to support doctors' decision making through the provision of electronic books containing a wide range of clinical knowledge and locally based information. WAX has been piloted in several regions in the United Kingdom and formally evaluated in 17 GP surgeries based in Cambridgeshire. The evaluation has provided evidence that WAX Active-Library significantly improves GPs' access to relevant information sources and by increasing appropriate patient management and referrals this might also lead to an improvement in clinical outcomes.

  4. Leaf Epicuticular Waxes of the Eceriferum Mutants in Arabidopsis.

    PubMed Central

    Jenks, M. A.; Tuttle, H. A.; Eigenbrode, S. D.; Feldmann, K. A.

    1995-01-01

    Wild-type Arabidopsis leaf epicuticular wax (EW) occurs as a smooth layer over the epidermal surface, whereas stem EW has a crystalline microstructure. Wild-type EW load was more than 10-fold lower on leaves than on stems. Compared with the EW on wild-type stems, EW on wild-type leaves had a much higher proportion of their total EW load in the form of alkanes and 1-alcohols; a large reduction in secondary alcohols, ketones, and esters; and a chain-length distribution for major EW classes that was skewed toward longer lengths. The eceriferum (cer) mutations often differentially affected leaf and stem EW chemical compositions. For example, the cer2 mutant EW phenotype was expressed on the stem but not on the leaf. Compared to wild type, the amount of primary alcohols on cer9 mutants was reduced on leaves but elevated on stems, whereas an opposite differential effect for primary alcohols was observed on cer16 leaves and stems. Putative functions for CER gene products are discussed. The CER4 and CER6 gene products may be involved in fatty aldehyde reduction and C26 fatty acylcoenzyme A elongation, respectively. CER1, CER8, CER9, and CER16 gene products may be involved in EW substrate transfer. The CER3 gene product may be involved in release of fatty acids from elongase complexes. CER2 gene product may have regulatory functions. PMID:12228482

  5. Cucumis sativus L. WAX2 Plays a Pivotal Role in Wax Biosynthesis, Influencing Pollen Fertility and Plant Biotic and Abiotic Stress Responses.

    PubMed

    Wang, Wenjiao; Liu, Xingwang; Gai, Xinshuang; Ren, Jiaojiao; Liu, Xiaofeng; Cai, Yanling; Wang, Qian; Ren, Huazhong

    2015-07-01

    Cuticular waxes play an important part in protecting plant aerial organs from biotic and abiotic stresses. In previous studies, the biosynthetic pathway of cuticular waxes and relative functional genes has been researched and understood; however, little is known in cucumber (Cucumis sativus L.). In this study, we cloned and characterized an AtWAX2 homolog, CsWAX2, in cucumber and found that it is highly expressed in the epidermis, where waxes are synthesized, while subcellular localization showed that CsWAX2 protein is localized to the endoplasmic reticulum (ER). The transcriptional expression of CsWAX2 was found to be induced by low temperature, drought, salt stress and ABA, while the ectopic expression of CsWAX2 in an Arabidopsis wax2 mutant could partially complement the glossy stem phenotype. Abnormal expression of CsWAX2 in transgenic cucumbers specifically affected both very long chain (VLC) alkanes and cutin biosynthesis. Furthermore, transgenic cucumber plants of CsWAX2 showed significant changes in pollen viability and fruit resistance to water loss and pathogens compared with the wild type. Collectively, these results indicated that CsWAX2 plays a pivotal role in wax biosynthesis, influencing pollen fertility and the plant's response to biotic and abiotic stresses. PMID:26023108

  6. Cucumis sativus L. WAX2 Plays a Pivotal Role in Wax Biosynthesis, Influencing Pollen Fertility and Plant Biotic and Abiotic Stress Responses.

    PubMed

    Wang, Wenjiao; Liu, Xingwang; Gai, Xinshuang; Ren, Jiaojiao; Liu, Xiaofeng; Cai, Yanling; Wang, Qian; Ren, Huazhong

    2015-07-01

    Cuticular waxes play an important part in protecting plant aerial organs from biotic and abiotic stresses. In previous studies, the biosynthetic pathway of cuticular waxes and relative functional genes has been researched and understood; however, little is known in cucumber (Cucumis sativus L.). In this study, we cloned and characterized an AtWAX2 homolog, CsWAX2, in cucumber and found that it is highly expressed in the epidermis, where waxes are synthesized, while subcellular localization showed that CsWAX2 protein is localized to the endoplasmic reticulum (ER). The transcriptional expression of CsWAX2 was found to be induced by low temperature, drought, salt stress and ABA, while the ectopic expression of CsWAX2 in an Arabidopsis wax2 mutant could partially complement the glossy stem phenotype. Abnormal expression of CsWAX2 in transgenic cucumbers specifically affected both very long chain (VLC) alkanes and cutin biosynthesis. Furthermore, transgenic cucumber plants of CsWAX2 showed significant changes in pollen viability and fruit resistance to water loss and pathogens compared with the wild type. Collectively, these results indicated that CsWAX2 plays a pivotal role in wax biosynthesis, influencing pollen fertility and the plant's response to biotic and abiotic stresses.

  7. A thermodynamic model for predicting wax formation in crude oils

    SciTech Connect

    Hansen, J.H.; Fredenslund, A.; Pedersen, K.S.; Renningsen, H.P.

    1988-12-01

    Most crude oils contain high molecular weight components, which at low temperatures may precipitate as a wax phase. This may cause plugging of pipes and numerous other problems. This paper presents a solid-liquid equilibrium based model for the description of wax formation. The model for the Gibbs energy contains a contribution based on Flory's theory of multicomponent polymer solutions and a contribution from a metastable subcooled state which oil mixtures may attain. The latter is formulated in terms of the surface tension of the wax phase. Experimental wax appearance points (temperatures), WAP's, are reported for 17 different stabilized North Sea crude oils. The values predicted by the new model are in very good agreement with the experimental WAP's.

  8. Wax deposition scale-up modeling for waxy crude production lines

    SciTech Connect

    Hsu, J.J.C.; Brubaker, J.P.

    1995-12-01

    A wax deposition scale-up model has been developed to scale-up laboratory wax deposition results for waxy crude production lines. The wax deposition model allows users to predict wax deposition profile along a cold pipeline and predict potential wax problems and pigging frequency. Consideration of the flow turbulence effect significantly increases prediction accuracy. Accurate wax deposition prediction should save capital and operation investments for waxy crude production systems. Many wax deposition models only apply a molecular diffusion mechanism in modeling and neglect shear effect. However, the flow turbulence effect has significant impact on wax deposition and can not be neglected in wax deposition modeling. Wax deposition scale-up parameters including shear rate, shear stress, and Reynolds number have been studied. None of these parameters can be used as a scaler. Critical wax tension concept has been proposed as a scaler. A technique to scale up shear effect and then wax deposition is described. For a given oil and oil temperature, the laboratory wax deposition data can be scaled up by heat flux and flow velocity. The scale-up techniques could be applied to multiphase flow conditions. Examples are presented in this paper to describe profiles of wax deposition and effective inside diameter along North Sea and West Africa subsea pipelines. The difference of wax deposition profiles from stock tank oil and live oil is also presented.

  9. Analysis of paraffin wax oxidates by differential infrared spectrometry

    SciTech Connect

    Nazir, M.

    1985-05-01

    The oxidation products of paraffin waxes are estimated by isolation followed by instrumental techniques which are laborious and time-consuming. Differential infrared spectrometry has been applied to analyze the usual paraffin wax oxidates. The saponification and the solubility problems encountered in these samples were overcome by the addition of crown ethers. The technique is quicker, less time-consuming, and less expensive and only a small sample size is required. 10 references, 2 figures, 1 table.

  10. Preoperative auricular wax pattern duplication for surgical template fabrication.

    PubMed

    Wang, R

    1999-05-01

    Craniofacial implants have been shown to provide excellent stability and retention for auricular prosthodontic rehabilitation. The locations of implant placement are critical to achieve optimal prosthetic results. This article describes a procedure for fabricating a surgical template from a diagnostic wax-up of an ear without destroying the wax pattern. A full-contour template can assist in proper positioning of craniofacial implants, which in turn can complement the prosthetic result.

  11. The use of diagnostic wax-ups in treatment planning.

    PubMed

    Garcia, Lily T; Bohnenkamp, David M

    2003-03-01

    The use of diagnostic wax-ups as diagnostic aids in treatment planning has been presented for use in various situations--from simple patient assessment to more extensive prosthodontic rehabilitation. Requesting a diagnostic wax-up from the dental technician may add to the expense of treatment planning for a patient because of the laboratory fee incurred for this service. The cost is negligible, considering the value of identifying potential treatment obstacles that could affect both treatment outcomes and patient satisfaction.

  12. Nest wax triggers worker reproduction in the bumblebee Bombus terrestris.

    PubMed

    Rottler-Hoermann, Ann-Marie; Schulz, Stefan; Ayasse, Manfred

    2016-01-01

    Social insects are well known for their high level of cooperation. Workers of the primitively eusocial bumblebee Bombus terrestris are able to produce male offspring in the presence of a queen. Nonetheless, they only compete for reproduction, in the so-called competition phase, when the workforce is large enough to support the rearing of reproductives. So far, little is known about the proximate mechanisms underlying the shift between altruism and selfish behaviour in bumblebee workers. In this study, we have examined the influence of chemical cues from the nest wax on the onset of worker reproduction. Chemical analyses of wax extracts have revealed that the patterns and amounts of cuticular lipids change considerably during colony development. These changes in wax scent mirror worker abundance and the presence of fertile workers. In bioassays with queen-right worker groups, wax affects the dominance behaviour and ovarian development of workers. When exposed to wax from a colony in competition phase, workers start to compete for reproduction. We suggest that wax scent enables workers to time their reproduction by providing essential information concerning the social condition of the colony. PMID:26909189

  13. Wax crystallization and aggregation in a model crude oil

    NASA Astrophysics Data System (ADS)

    Vignati, Emanuele; Piazza, Roberto; Visintin, Ruben F. G.; Lapasin, Romano; D'Antona, Paolo; Lockhart, Thomas P.

    2005-11-01

    The high-molecular-weight paraffinic ('wax') fraction separates from crude oils at low temperatures, a process that can lead to a sol-gel transition when the mass of wax solids exceeds 1-2%. Attractive interactions between the micron-size wax solids suspended in the non-polar medium have been suggested to be responsible for gel formation. The present study reports an optically transparent model oil system, based on a mixture of linear and branched paraffins. Rheological measurements and optical microscopy show that the model system reproduces essential features of crude oil gels. Small-angle light scattering studies conducted at temperatures intermediate between the cloud point (58 °C) and sol-gel transition (39 °C) show that phase separation and wax solid aggregation are rapid processes, leading to the formation of dynamically arrested structures well above the sol-gel transition determined rheologically. Analysis of gravity settling effects has provided a rough estimate for the yield stress of the wax particle network formed (greater than 0.7 Pa at 45 °C and 0.07 Pa at 55 °C). Clusters formed by the aggregated wax solids possess a fractal dimension of about 1.8, consistent with diffusion-limited cluster-cluster aggregation.

  14. Nest wax triggers worker reproduction in the bumblebee Bombus terrestris

    PubMed Central

    Rottler-Hoermann, Ann-Marie; Schulz, Stefan; Ayasse, Manfred

    2016-01-01

    Social insects are well known for their high level of cooperation. Workers of the primitively eusocial bumblebee Bombus terrestris are able to produce male offspring in the presence of a queen. Nonetheless, they only compete for reproduction, in the so-called competition phase, when the workforce is large enough to support the rearing of reproductives. So far, little is known about the proximate mechanisms underlying the shift between altruism and selfish behaviour in bumblebee workers. In this study, we have examined the influence of chemical cues from the nest wax on the onset of worker reproduction. Chemical analyses of wax extracts have revealed that the patterns and amounts of cuticular lipids change considerably during colony development. These changes in wax scent mirror worker abundance and the presence of fertile workers. In bioassays with queen-right worker groups, wax affects the dominance behaviour and ovarian development of workers. When exposed to wax from a colony in competition phase, workers start to compete for reproduction. We suggest that wax scent enables workers to time their reproduction by providing essential information concerning the social condition of the colony. PMID:26909189

  15. Differences in Substrate Specificities of Five Bacterial Wax Ester Synthases

    PubMed Central

    Wahlen, Bradley D.; Garner, EmmaLee; Wei, Jiashi; Seefeldt, Lance C.

    2012-01-01

    Wax esters are produced in certain bacteria as a potential carbon and energy storage compound. The final enzyme in the biosynthetic pathway responsible for wax ester production is the bifunctional wax ester synthase/acyl-coenzyme A (acyl-CoA):diacylglycerol acyltransferase (WS/DGAT), which utilizes a range of fatty alcohols and fatty acyl-CoAs to synthesize the corresponding wax ester. We report here the isolation and substrate range characterization for five WS/DGAT enzymes from four different bacteria: Marinobacter aquaeolei VT8, Acinetobacter baylyi, Rhodococcus jostii RHA1, and Psychrobacter cryohalolentis K5. The results from kinetic studies of isolated enzymes reveal a differential activity based on the order of substrate addition and reveal subtle differences between the substrate selectivity of the different enzymes. These in vitro results are compared to the wax ester and triacylglyceride product profiles obtained from each organism grown under neutral lipid accumulating conditions, providing potential insights into the role that the WS/DGAT enzyme plays in determining the final wax ester products that are produced under conditions of nutrient stress in each of these bacteria. Further, the analysis revealed that one enzyme in particular from M. aquaeolei VT8 showed the greatest potential for future study based on rapid purification and significantly higher activity than was found for the other isolated WS/DGAT enzymes. The results provide a framework to test prospective differences between these enzymes for potential biotechnological applications such as high-value petrochemicals and biofuel production. PMID:22685145

  16. Nest wax triggers worker reproduction in the bumblebee Bombus terrestris.

    PubMed

    Rottler-Hoermann, Ann-Marie; Schulz, Stefan; Ayasse, Manfred

    2016-01-01

    Social insects are well known for their high level of cooperation. Workers of the primitively eusocial bumblebee Bombus terrestris are able to produce male offspring in the presence of a queen. Nonetheless, they only compete for reproduction, in the so-called competition phase, when the workforce is large enough to support the rearing of reproductives. So far, little is known about the proximate mechanisms underlying the shift between altruism and selfish behaviour in bumblebee workers. In this study, we have examined the influence of chemical cues from the nest wax on the onset of worker reproduction. Chemical analyses of wax extracts have revealed that the patterns and amounts of cuticular lipids change considerably during colony development. These changes in wax scent mirror worker abundance and the presence of fertile workers. In bioassays with queen-right worker groups, wax affects the dominance behaviour and ovarian development of workers. When exposed to wax from a colony in competition phase, workers start to compete for reproduction. We suggest that wax scent enables workers to time their reproduction by providing essential information concerning the social condition of the colony.

  17. Calculation of the store house worker dose in a lost wax foundry using MCNP-4C.

    PubMed

    Alegría, Natalia; Legarda, Fernando; Herranz, Margarita; Idoeta, Raquel

    2005-01-01

    Lost wax casting is an industrial process which permits the transmutation into metal of models made in wax. The wax model is covered with a silicaceous shell of the required thickness and once this shell is built the set is heated and wax melted. Liquid metal is then cast into the shell replacing the wax. When the metal is cool, the shell is broken away in order to recover the metallic piece. In this process zircon sands are used for the preparation of the silicaceous shell. These sands have varying concentrations of natural radionuclides: 238U, 232Th and 235U together with their progenics. The zircon sand is distributed in bags of 50 kg, and 30 bags are on a pallet, weighing 1,500 kg. The pallets with the bags have dimensions 80 cm x 120 cm x 80 cm, and constitute the radiation source in this case. The only pathway of exposure to workers in the store house is external radiation. In this case there is no dust because the bags are closed and covered by plastic, the store house has a good ventilation rate and so radon accumulation is not possible. The workers do not touch with their hands the bags and consequently skin contamination will not take place. In this study all situations of external irradiation to the workers have been considered; transportation of the pallets from vehicle to store house, lifting the pallets to the shelf, resting of the stock on the shelf, getting down the pallets, and carrying the pallets to production area. Using MCNP-4C exposure situations have been simulated, considering that the source has a homogeneous composition, the minimum stock in the store house is constituted by 7 pallets, and the several distances between pallets and workers when they are at work. The photons flux obtained by MCNP-4C is multiplied by the conversion factor of Flux to Kerma for air by conversion factor to Effective Dose by Kerma unit, and by the number of emitted photons. Those conversion factors are obtained of ICRP 74 table 1 and table 17 respectively. This

  18. Leaf Wax δ13C Varies with Elevation in the Peruvian Andes and Western Amazonia

    NASA Astrophysics Data System (ADS)

    Wu, M. S.; Feakins, S. J.; Ponton, C.; Peters, T.; West, A. J.; Galy, V.; Bentley, L. P.; Salinas, N.; Shenkin, A.; Martin, R.; Asner, G. P.; Malhi, Y.

    2015-12-01

    Plant leaf wax carbon isotopic composition (δ13Cwax) reflects the net isotopic effects associated with diffusion into the leaf, fixation of carbon by Rubisco and biosynthesis of individual leaf wax biochemicals. As declining pCO2 with elevation affects the first two fractionations, we expect to find an isotopic gradient in δ13Cwax, if the fractionation of leaf wax biosynthesis is constant. To test this, we report δ13Cwax values from 500 samples of leaves collected by tree-climbers from the upper canopy from 9 forest-inventory plots spanning a 3.5km elevation transect in the Peruvian Andes and western Amazonia during the CHAMBASA field campaign. These samples provide a unique opportunity to study the relationship between δ13Cwax and pCO2 in diverse species across this remote tropical montane forest and lowland rainforest. The very wet climate throughout (2-5 m rainfall per year) minimizes fractionation effects due to stomatal restrictions (i.e. water use efficiency) that may be an important factor elsewhere. Preliminary results show δ13Cwax values on average increase with elevation by ~1.5‰/km, a trend consistent with bulk plant δ13C in previous studies. The mean epsilon between bulk and C29 n-alkane is -7.3±2.2‰. Inter-sample differences are large on the order of 10‰. Shaded leaves and understory leaves are found to be depleted relative to sunlit leaves, presumably due to a lower photosynthetic rate and use of respired CO2 in the understory. C29 n-alkanes are on average ~2.5‰ more depleted than C30 n-alkanoic acids, indicating fractionation during selective decarboxylation. We further compare results from plants with soil and river sediments to provide insights into how leaf wax signals are archived in soils and exported from the landscape. We find a ~1.4‰/km gradient in forest soils similar to plants. We observe a ~2‰ offset between C29 n-alkane in plant leaves and in soils across the elevation profile, which is likely a signal of degradation

  19. Removal of Wax and Stickies from OCC by Flotation

    SciTech Connect

    M. R. Doshi; J. Dyer

    2000-01-31

    Laboratory research indicates that wax is amenable to removal by froth flotation provided it is free or detached from the fiber. The only effective means, at this time, of maximizing detachment of wax is through the use of low consistency pulping at temperatures above the melting point of wax. Wax removal from WCC through washing, flotation, or a combination of both was approximately 90% in these laboratory studies, indicating that not all of the wax is detached from fibers. These results were summarized in Annual Report 1, December 1, 1997 to November 30, 1998. Pilot trials were conducted in which the authors simulated a conventional OCC repulping process with and without flotation. Additional aggressive washing and water clarification were also examined during the study. The inclusion of flotation in the OCC stock preparation system significantly improved the removal of wax spots and extractable material from the furnish. Based on this study, the authors predict that a compact flotation system with 2 lb surfactant/ton of fiber would improve the OCC pulp quality with regard to wax spots by 60% and would not negatively affect strength properties. Flotation losses would be in the 2-5% range. Two mill trials were conducted during the last quarter of the project. One trial was carried out at Green Bay Packaging, Green Bay, WI, and a second trial was conducted at Menasha Corporation, Otsego, MI. A 250-liter Voith Sulzer Ecocell was used to evaluate the removal of wax and stickies from the OCC processing systems at these two mills. The inclusion of flotation in the OCC stock preparation system significantly improved the removal of wax spots from the furnish. The data indicate that flotation was more effective in removing wax and stickies than reverse cleaners. The mill trials have demonstrated that flotation can be substituted for or replace existing reverse cleaning systems and, in some cases, can replace dispersion systems. In this manner, the use of flotation can

  20. Self assembly of epicuticular waxes on living plant surfaces imaged by atomic force microscopy (AFM).

    PubMed

    Koch, Kerstin; Neinhuis, Christoph; Ensikat, Hans-Jürgen; Barthlott, Wilhelm

    2004-03-01

    The cuticle of terrestrial vascular plants and some bryophytes is covered with a complex mixture of lipids, usually called epicuticular waxes. Self-assembly processes of wax molecules lead to crystalline three-dimensional micro- and nanostructures that emerge from an underlying wax film. This paper presents the first AFM study on wax regeneration on the surfaces of living plants and the very early stages of wax crystal formation at the molecular level. Wax formation was analysed on the leaves of Euphorbia lathyris, Galanthus nivalis, and Ipheion uniflorum. Immediately after wax removal, regeneration of a wax film began, consisting of individual layers of, typically, 3-5 nm thickness. Subsequently, several different stages of crystal growth could be distinguished, and different patterns of wax regeneration as well as considerable variation in regeneration speed were found.

  1. Enhanced expression of EsWAX1 improves drought tolerance with increased accumulation of cuticular wax and ascorbic acid in transgenic Arabidopsis.

    PubMed

    Zhu, Lin; Guo, Jiansheng; Zhu, Jian; Zhou, Cheng

    2014-02-01

    Drought can activate several stress responses in plants, such as stomatal closure, accumulation of cuticular wax and ascorbic acid (AsA), which have been correlated with improvement of drought tolerance. In this study, a novel MYB gene, designed as EsWAX1, was isolated and characterized from Eutrema salsugineum. EsWAX1 contained a full-length open reading frame (ORF) of 1068 bp, which encoding 355 amino acids. Transcript levels of EsWAX1 were quickly inducible by drought stress and ABA treatment, indicating that EsWAX1 may act as a positive regulator in response to drought stress. Ectopic expression of EsWAX1 increased accumulation of cuticular wax via modulating the expression of several wax-related genes, such as CER1, KCS2 and KCR1. Scanning electron microscopy further revealed higher densities of wax crystalline structures on the adaxial surfaces of leaves in transgenic Arabidopsis plants. In addition, the expression of several AsA biosynthetic genes (VTC1, GLDH and MIOX4) was significantly up-regulated in EsWAX1-overexpressing lines and these transgenic plants have approximately 23-27% more total AsA content than WT plants. However, the high-level expression of EsWAX1 severely disrupted plant normal growth and development. To reduce negative effects of EsWAX1 over-expression on plant growth, we generated transgenic Arabidopsis plants expressing EsWAX1 driven by the stress-inducible RD29A promoter. Our data indicated the RD29A::EsWAX1 transgenic plants had greater tolerance to drought stress than wild-type plants. Taken together, the EsWAX1 gene is a potential regulator that may be utilized to improve plant drought tolerance by genetic manipulation.

  2. Is wax equivalent to tissue in electron conformal therapy planning? A Monte Carlo study of material approximation introduced dose difference.

    PubMed

    Zhang, Ray R; Feygelman, Vladimir; Harris, Eleanor R; Rao, Nikhil; Moros, Eduardo G; Zhang, Geoffrey G

    2013-01-07

    With CT-based Monte Carlo (MC) dose calculations, material composition is often assigned based on the standard Hounsfield unit ranges. This is known as the density threshold method. In bolus electron conformal therapy (BolusECT), the bolus material, machineable wax, would be assigned as soft tissue and the electron density is assumed equivalent to soft tissue based on its Hounsfield unit. This study investigates the dose errors introduced by this material assignment. BEAMnrc was used to simulate electron beams from a Trilogy accelerator. SPRRZnrc was used to calculate stopping power ratios (SPR) of tissue to wax, SPR (tissue) (wax), and tissue to water, SPR(tissue) (water), for 6, 9, 12, 15, and 18 MeV electron beams, of which 12 and 15MeV beams are the most commonly used energies in BolusECT. DOSXYZnrc was applied in dose distribution calculations in a tissue phantom with either flat wax slabs of various thicknesses or a wedge-shaped bolus on top. Dose distribution for two clinical cases, a chest wall and a head and neck, were compared with the bolus material treated as wax or tissue. The SPR(tissue) (wax) values for 12 and 15MeV beams are between 0.935 and 0.945, while the SPR(tissue) (water) values are between 0.990 and 0.991. For a 12 MeV beam, the dose in tissue immediately under the bolus is overestimated by 2.5% for a 3 cm bolus thickness if the wax bolus is treated as tissue. For 15 MeV beams, the error is 1.4%. However, in both clinical cases the differences in the PTV DVH is negligible. Due to stopping power differences, dose differences of up to 2.5% are observed in MC simulations if the bolus material is misassigned as tissue in BolusECT dose calculations. However, for boluses thinner than 2 cm that are more likely encountered in practice, the error is within clinical tolerance.

  3. Late Quaternary environmental change in the interior South American tropics: new insight from leaf wax stable isotopes

    NASA Astrophysics Data System (ADS)

    Fornace, Kyrstin L.; Whitney, Bronwen S.; Galy, Valier; Hughen, Konrad A.; Mayle, Francis E.

    2016-03-01

    Stable isotope analysis of leaf waxes in a sediment core from Laguna La Gaiba, a shallow lake located at the Bolivian margin of the Pantanal wetlands, provides new perspective on vegetation and climate change in the lowland interior tropics of South America over the past 40,000 years. The carbon isotopic compositions (δ13C) of long-chain n-alkanes reveal large shifts between C3- and C4-dominated vegetation communities since the last glacial period, consistent with landscape reconstructions generated with pollen data from the same sediment core. Leaf wax δ13C values during the last glacial period reflect an open landscape composed of C4 grasses and C3 herbs from 41-20 ka. A peak in C4 abundance during the Last Glacial Maximum (LGM, ∼21 ka) suggests drier or more seasonal conditions relative to the earlier glacial period, while the development of a C3-dominated forest community after 20 ka points to increased humidity during the last deglaciation. Within the Holocene, large changes in the abundance of C4 vegetation indicate a transition from drier or more seasonal conditions during the early/mid-Holocene to wetter conditions in the late Holocene coincident with increasing austral summer insolation. Strong negative correlations between leaf wax δ13C and δD values over the entire record indicate that the majority of variability in leaf wax δD at this site can be explained by variability in the magnitude of biosynthetic fractionation by different vegetation types rather than changes in meteoric water δD signatures. However, positive δD deviations from the observed δ13C- δD trends are consistent with more enriched source water and drier or more seasonal conditions during the early/mid-Holocene and LGM. Overall, our record adds to evidence of varying influence of glacial boundary conditions and orbital forcing on South American Summer Monsoon precipitation in different regions of the South American tropics. Moreover, the relationships between leaf wax stable

  4. Dogfish egg case structural studies by ATR FT-IR and FT-Raman spectroscopy.

    PubMed

    Iconomidou, Vassiliki A; Georgaka, Martha E; Chryssikos, Georgios D; Gionis, Vassilis; Megalofonou, Persefoni; Hamodrakas, Stavros J

    2007-06-01

    The dogfish egg case is a composite structure that combines mechanical tensile strength, toughness and elasticity with high permeability to small molecules and ions. Presumably, it provides both a protective and a filtering role for the egg/embryo contained within it. In this work, we performed structural studies of the Galeus melastomus egg case at two different stages of the hardening process, utilizing ATR FT-IR and FT-Raman spectroscopy. Based on these data we deduce that: (a) The G. melastomus egg case, in close analogy to that of the related species Scyliorhinus cunicula, is a complex, composite structure which consists mainly of an analogue of collagen IV. This network forming protein appears to have common secondary structural characteristics in the entire egg case. (b) The outermost layer of the non-sclerotized egg case is especially rich in tyrosine, while the innermost layer is rich in polysaccharides, presumably glycosaminoglycans, and lipids. These differences are diminished upon hardening. (c) Disulfide bonds do not appear to play a significant role in cross-linking. However, cross-links involving tyrosine residues appear to sclerotize the egg case. It is proposed that the intensity of the Raman band at ca. 1615 cm(-1), which is due to ring stretching vibrations of Tyr, might be a useful indicator of the sclerotization status of a certain proteinaceous tissue, when tyrosines are involved in sclerotization mechanisms. PMID:17292464

  5. A Novel Pathway for Triacylglycerol Biosynthesis Is Responsible for the Accumulation of Massive Quantities of Glycerolipids in the Surface Wax of Bayberry (Myrica pensylvanica) Fruit[OPEN

    PubMed Central

    Ohlrogge, John B.

    2016-01-01

    Bayberry (Myrica pensylvanica) fruits synthesize an extremely thick and unusual layer of crystalline surface wax that accumulates to 32% of fruit dry weight, the highest reported surface lipid accumulation in plants. The composition is also striking, consisting of completely saturated triacylglycerol, diacylglycerol, and monoacylglycerol with palmitate and myristate acyl chains. To gain insight into the unique properties of Bayberry wax synthesis, we examined the chemical and morphological development of the wax layer, monitored wax biosynthesis through [14C]-radiolabeling, and sequenced the transcriptome. Radiolabeling identified sn-2 monoacylglycerol as an initial glycerolipid intermediate. The kinetics of [14C]-DAG and [14C]-TAG accumulation and the regiospecificity of their [14C]-acyl chains indicated distinct pools of acyl donors and that final TAG assembly occurs outside of cells. The most highly expressed lipid-related genes were associated with production of cutin, whereas transcripts for conventional TAG synthesis were >50-fold less abundant. The biochemical and expression data together indicate that Bayberry surface glycerolipids are synthesized by a pathway for TAG synthesis that is related to cutin biosynthesis. The combination of a unique surface wax and massive accumulation may aid understanding of how plants produce and secrete non-membrane glycerolipids and also how to engineer alternative pathways for lipid production in non-seeds. PMID:26744217

  6. Loss of Abaxial Leaf Epicuticular Wax in Medicago truncatula irg1/palm1 Mutants Results in Reduced Spore Differentiation of Anthracnose and Nonhost Rust Pathogens[W

    PubMed Central

    Uppalapati, Srinivasa Rao; Ishiga, Yasuhiro; Doraiswamy, Vanthana; Bedair, Mohamed; Mittal, Shipra; Chen, Jianghua; Nakashima, Jin; Tang, Yuhong; Tadege, Million; Ratet, Pascal; Chen, Rujin; Schultheiss, Holger; Mysore, Kirankumar S.

    2012-01-01

    To identify genes that confer nonhost resistance to biotrophic fungal pathogens, we did a forward-genetics screen using Medicago truncatula Tnt1 retrotransposon insertion lines. From this screen, we identified an inhibitor of rust germ tube differentation1 (irg1) mutant that failed to promote preinfection structure differentiation of two rust pathogens, Phakopsora pachyrhizi and Puccinia emaculata, and one anthracnose pathogen, Colletotrichum trifolii, on the abaxial leaf surface. Cytological and chemical analyses revealed that the inhibition of rust preinfection structures in irg1 mutants is due to complete loss of the abaxial epicuticular wax crystals and reduced surface hydrophobicity. The composition of waxes on abaxial leaf surface of irg1 mutants had >90% reduction of C30 primary alcohols and a preferential increase of C29 and C31 alkanes compared with the wild type. IRG1 encodes a Cys(2)His(2) zinc finger transcription factor, PALM1, which also controls dissected leaf morphology in M. truncatula. Transcriptome analysis of irg1/palm1 mutants revealed downregulation of eceriferum4, an enzyme implicated in primary alcohol biosynthesis, and MYB96, a major transcription factor that regulates wax biosynthesis. Our results demonstrate that PALM1 plays a role in regulating epicuticular wax metabolism and transport and that epicuticular wax influences spore differentiation of host and nonhost fungal pathogens. PMID:22294617

  7. A Novel Pathway for Triacylglycerol Biosynthesis Is Responsible for the Accumulation of Massive Quantities of Glycerolipids in the Surface Wax of Bayberry (Myrica pensylvanica) Fruit.

    PubMed

    Simpson, Jeffrey P; Ohlrogge, John B

    2016-01-01

    Bayberry (Myrica pensylvanica) fruits synthesize an extremely thick and unusual layer of crystalline surface wax that accumulates to 32% of fruit dry weight, the highest reported surface lipid accumulation in plants. The composition is also striking, consisting of completely saturated triacylglycerol, diacylglycerol, and monoacylglycerol with palmitate and myristate acyl chains. To gain insight into the unique properties of Bayberry wax synthesis, we examined the chemical and morphological development of the wax layer, monitored wax biosynthesis through [(14)C]-radiolabeling, and sequenced the transcriptome. Radiolabeling identified sn-2 monoacylglycerol as an initial glycerolipid intermediate. The kinetics of [(14)C]-DAG and [(14)C]-TAG accumulation and the regiospecificity of their [(14)C]-acyl chains indicated distinct pools of acyl donors and that final TAG assembly occurs outside of cells. The most highly expressed lipid-related genes were associated with production of cutin, whereas transcripts for conventional TAG synthesis were >50-fold less abundant. The biochemical and expression data together indicate that Bayberry surface glycerolipids are synthesized by a pathway for TAG synthesis that is related to cutin biosynthesis. The combination of a unique surface wax and massive accumulation may aid understanding of how plants produce and secrete non-membrane glycerolipids and also how to engineer alternative pathways for lipid production in non-seeds.

  8. Perinaphthenone phototransformation in a model of leaf epicuticular waxes.

    PubMed

    Trivella, Aurélien S; Monadjemi, Shirin; Worrall, David R; Kirkpatrick, Iain; Arzoumanian, Emmanuel; Richard, Claire

    2014-01-01

    Perinaphthenone (1H-phenalen-1-one, PN) is a reference photosensitizer producing singlet oxygen with a quantum yield close to one in a large variety of solvents. It is also the basic structure of a class of phototoxic phytoalexins. In this work, the PN photoreactivity was studied for the first time in a paraffinic wax, used as model of leaf epicuticular waxes. The PN photodegradation was monitored by UV-Vis spectroscopy. The triplet excited state, singlet oxygen and the hydroxyperinaphthenyl radical were detected by diffuse reflectance laser flash photolysis, near infrared phosphorescence and by EPR spectroscopy, respectively. The PN phototransformation was found to be fivefold faster in the wax than in n-heptane under steady-state irradiation. The hydroxyperinaphthenyl radical formation was observed in aerated irradiated paraffin wax while in n-heptane solution the radical was observed only in the absence of oxygen. These results show that under continuous irradiation, PN is much more easily phototransformed in a solid environment than in solution. Several photoproducts were identified, in particular phenalanone, PN dimers, and oxidized PN-alkanes adducts. Finally, when pyrethrum extract is added into the wax along with PN, the hydroxyperinaphthenyl radical concentration was increased by a factor of 2.4. Such photochemical reactions may occur when systemic pesticides enter the plant cuticle.

  9. Calculations aid breaking of wax-plugged lines

    SciTech Connect

    Gilchrist, R.T. Jr.

    1986-08-01

    Manipulation of pressure/volume data helps locate a wax plug in a pipeline, and it may then be possible to clear the line by interception of the plug with a hot tap. Or, in an extreme case, information obtained from the pressure/volume data will allow better assessment of where to replace the pipe. The possibility of a pipeline becoming plugged by paraffin buildup is greatest in winter when cooler temperatures may cause wax to precipitate and plate out on the pipe walls or completely gel in the line. The risk of plugging is also greatest during pigging. This is because passage of the pig may cause a large mass of wax to accumulate by scraping a thin layer of wax from a long length of pipe. This type of plug does not enlarge once the pipeline is stopped up. It has been successfully cleared by tapping the pipeline at a point within the wax blockage and then pumping the plug out in sections.

  10. Spherulitic growth of wax in the presence of kinetic inhibitors

    NASA Astrophysics Data System (ADS)

    Hutter, Jeffrey L.; Smith, Chris; Khmaladze, Alexander

    2001-03-01

    The petroleum industry has developed polymeric additives to prevent the precipitation of wax from diesel fuels in cold climates. These additives affect the crystallization kinetics of wax growth without affecting the thermodynamics. Some additives apparently operate by adsorbing to crystalline surfaces and blocking step flow, though direct evidence is lacking. We have used optical microscopy to study this process in model n-alkane systems with inhibitors added as a 1 wt% impurity. We find that the presence of the polymer dramatically alters the growth morphology of the wax --- rather than the usual plate-like growth, we see forms with all of the attributes of spherulites typical of bulk polymer growth, including radially oriented lamellae and banding. Since models for spherulitic growth postulate lamellar alignment by entropic pressure due to dangling polymer chains, the surface-adsorbed polymers are likely responsible for the similar alignment in wax spherulites. The banding seen in this case, however, results from periodic growth, rather than from the lamellar twisting seen in traditional polymer spherulites. We have modeled this effect as a coupling between the polymer adsorption rate and the growth rate of wax crystals.

  11. Genetic control of cuticular wax compounds in Eucalyptus globulus.

    PubMed

    Gosney, Benjamin J; Potts, Brad M; O'Reilly-Wapstra, Julianne M; Vaillancourt, René E; Fitzgerald, Hugh; Davies, Noel W; Freeman, Jules S

    2016-01-01

    Plant cuticular wax compounds perform functions that are essential for the survival of terrestrial plants. Despite their importance, the genetic control of these compounds is poorly understood outside of model taxa. Here we investigate the genetic basis of variation in cuticular compounds in Eucalyptus globulus using quantitative genetic and quantitative trait loci (QTL) analyses. Quantitative genetic analysis was conducted using 246 open-pollinated progeny from 13 native sub-races throughout the geographic range. QTL analysis was conducted using 112 clonally replicated progeny from an outcross F2 population. Nine compounds exhibited significant genetic variation among sub-races with three exhibiting signals of diversifying selection. Fifty-two QTL were found with co-location of QTL for related compounds commonly observed. Notable among these was the QTL for five wax esters, which co-located with a gene from the KCS family, previously implicated in the biosynthesis of cuticular waxes in Arabidopsis. In combination, the QTL and quantitative genetic analyses suggest the variation and differentiation in cuticular wax compounds within E. globulus has a complex genetic origin. Sub-races exhibited independent latitudinal and longitudinal differentiation in cuticular wax compounds, likely reflecting processes such as historic gene flow and diversifying selection acting upon genes that have diverse functions in distinct biochemical pathways.

  12. SWiFT Software Quality Assurance Plan.

    SciTech Connect

    Berg, Jonathan Charles

    2016-01-01

    This document describes the software development practice areas and processes which contribute to the ability of SWiFT software developers to provide quality software. These processes are designed to satisfy the requirements set forth by the Sandia Software Quality Assurance Program (SSQAP). APPROVALS SWiFT Software Quality Assurance Plan (SAND2016-0765) approved by: Department Manager SWiFT Site Lead Dave Minster (6121) Date Jonathan White (6121) Date SWiFT Controls Engineer Jonathan Berg (6121) Date CHANGE HISTORY Issue Date Originator(s) Description A 2016/01/27 Jon Berg (06121) Initial release of the SWiFT Software Quality Assurance Plan

  13. In vivo chemical and structural analysis of plant cuticular waxes using stimulated Raman scattering microscopy.

    PubMed

    Littlejohn, George R; Mansfield, Jessica C; Parker, David; Lind, Rob; Perfect, Sarah; Seymour, Mark; Smirnoff, Nicholas; Love, John; Moger, Julian

    2015-05-01

    The cuticle is a ubiquitous, predominantly waxy layer on the aerial parts of higher plants that fulfils a number of essential physiological roles, including regulating evapotranspiration, light reflection, and heat tolerance, control of development, and providing an essential barrier between the organism and environmental agents such as chemicals or some pathogens. The structure and composition of the cuticle are closely associated but are typically investigated separately using a combination of structural imaging and biochemical analysis of extracted waxes. Recently, techniques that combine stain-free imaging and biochemical analysis, including Fourier transform infrared spectroscopy microscopy and coherent anti-Stokes Raman spectroscopy microscopy, have been used to investigate the cuticle, but the detection sensitivity is severely limited by the background signals from plant pigments. We present a new method for label-free, in vivo structural and biochemical analysis of plant cuticles based on stimulated Raman scattering (SRS) microscopy. As a proof of principle, we used SRS microscopy to analyze the cuticles from a variety of plants at different times in development. We demonstrate that the SRS virtually eliminates the background interference compared with coherent anti-Stokes Raman spectroscopy imaging and results in label-free, chemically specific confocal images of cuticle architecture with simultaneous characterization of cuticle composition. This innovative use of the SRS spectroscopy may find applications in agrochemical research and development or in studies of wax deposition during leaf development and, as such, represents an important step in the study of higher plant cuticles.

  14. Wax-tear and meibum protein, wax-β-carotene interactions in vitro using infrared spectroscopy.

    PubMed

    Faheem, Samad; Kim, Sung-Hye; Nguyen, Jonathan; Neravetla, Shantanu; Ball, Matthew; Foulks, Gary N; Yappert, Marta C; Borchman, Douglas

    2012-07-01

    Protein-meibum and terpenoids-meibum lipid interactions could be important in the etiology of meibomian gland dysfunction (MGD) and dry eye symptoms. In the current model studies, attenuated total reflectance (ATR) infrared (IR) spectroscopy was used to determine if the terpenoid β-carotene and the major proteins in tears and meibum affect the hydrocarbon chain conformation and carbonyl environment of wax, an abundant component of meibum. The main finding of these studies is that mucin binding to wax disordered slightly the conformation of the hydrocarbon chains of wax and caused the wax carbonyls to become hydrogen bonded or experience a more hydrophilic environment. Lysozyme and lactoglobulin, two proteins shown to bind to monolayers of meibum, did not have such an effect. Keratin and β-carotene did not affect the fluidity (viscosity) or environment of the carbonyl moieties of wax. Based on these results, tetraterpenoids are not likely to influence the structure of meibum in the meibomian glands. In addition, these findings suggest that it is unlikely that keratin blocks meibomian glands by causing the meibum to become more viscous. Among the tear fluid proteins studied, mucin is the most likely to influence the conformation and carbonyl environment of meibum at the tear film surface.

  15. The molecular signatures of Taxodiaceae / Cupressaceae / Taxaceae (TCT) leaf waxes in modern and ancient samples

    NASA Astrophysics Data System (ADS)

    Ho, M.; Zinniker, D.; Green Nylen, N.; Moldowan, J. M.; Denisevich, P.

    2005-12-01

    optimized for the synthesis of C34 and C36 fatty acids. The bimodal distribution of n-alkanes (abundant C25 and C27 and abundant C33 and C35) in some Cupressus species indicates that the expression of this VLCFA elongase may be spatially or temporally limited in some taxa. Examples of fossil TCT leaf waxes have been observed in Pleistocene coastal sediments from California and Washington and in Jurassic coals from the Turpan basin in western China. These wax contributions can be identified by their unique n-alkane and diterpenoid signatures and their relationship with macrofossil and/or microfossil remains tied to members of the TCT complex. The carbon isotopic composition of Pleistocene waxes is consistent with a rainforest or marsh adapted TCT taxon (possibly Thuja plicata), while the isotopic composition of the Jurassic waxes is indicative of a highly water stressed taxon. Unique enzymes for very long chain n-alkane biosynthesis in the core group of TCT taxa listed above may have arisen during the early Mesozoic in a desert or salt marsh adapted species in response to extreme temperatures or water stress.

  16. The proteomics of formalin-fixed wax-embedded tissue.

    PubMed

    Vincenti, David Cilia; Murray, Graeme I

    2013-04-01

    Proteomics, which is the global analysis of protein expression in cells and tissues, has emerged over the last ten to fifteen years as a key set of technologies to improve our understanding of disease processes and to identify new diagnostic, prognostic and predictive disease biomarkers. Whilst most proteomic studies have been conducted on fresh frozen tissue, the continuous improvements in technical procedures for protein extraction and separation, coupled with increasingly powerful bioinformatics, have provided the opportunity for proteomic analysis to be conducted on formalin-fixed wax-embedded tissue. This potential advance should allow proteomic analysis to be performed on the extensive archives of clinically annotated formalin fixed wax embedded tissue blocks stored in pathology departments worldwide. In this review the main techniques and their limitations involved in proteomic analysis of formalin fixed wax embedded tissue will be outlined and examples of their successful application will be indicated.

  17. Fungal contamination of paraffin wax blocks in a pathology archive.

    PubMed

    Müller, K; Ellenberger, C; Aupperle, H; Schmäschke, R; Scheller, R; Wittenbrink, M M; Schoon, H-A

    2011-01-01

    While searching for paraffin wax blocks for research purposes in our archive we detected numerous larval and some dead adult moths. Some wax blocks were riddled with a white-brown crumbling substance. The entire archive was checked and profoundly-infested blocks were separated from unaffected blocks. Mycological and parasitological investigations were performed. Fungi were identified by culture and polymerase chain reaction, which revealed high sequence homology to six different fungal species. The moths were determined to be Nemapogon personellus. A total of 8,484 wax blocks had to be removed from the archive and destroyed. Pathologists should be alerted to the importance of checking the humidity of the air where archival material is stored.

  18. Micro encapsulation in situ with super permeating molten wax

    SciTech Connect

    Carter, E.

    2007-07-01

    A new class of grout material based on molten wax offers a dramatic improvement in permeation grouting performance. This new material makes a perfect in situ containment of buried radioactive waste both feasible and cost effective. This paper describes various ways the material can be used to isolate buried waste in situ. Potential applications described in the paper include buried radioactive waste in deep trenches, deep shafts, Infiltration trenches, and large buried objects. Use of molten wax for retrieval of waste is also discussed. Wax can also be used for retrieval of air sensitive materials or drummed waste. This paper provides an analysis of the methods of application and the expected performance and cost of several potential projects. (authors)

  19. Fungal contamination of paraffin wax blocks in a pathology archive.

    PubMed

    Müller, K; Ellenberger, C; Aupperle, H; Schmäschke, R; Scheller, R; Wittenbrink, M M; Schoon, H-A

    2011-01-01

    While searching for paraffin wax blocks for research purposes in our archive we detected numerous larval and some dead adult moths. Some wax blocks were riddled with a white-brown crumbling substance. The entire archive was checked and profoundly-infested blocks were separated from unaffected blocks. Mycological and parasitological investigations were performed. Fungi were identified by culture and polymerase chain reaction, which revealed high sequence homology to six different fungal species. The moths were determined to be Nemapogon personellus. A total of 8,484 wax blocks had to be removed from the archive and destroyed. Pathologists should be alerted to the importance of checking the humidity of the air where archival material is stored. PMID:21333307

  20. Wax inhibition by comb-like polymers: support of the incorporation-perturbation mechanism from molecular dynamics simulations.

    PubMed

    Jang, Yun Hee; Blanco, Mario; Creek, Jefferson; Tang, Yongchun; Goddard, William A

    2007-11-22

    Deposition of wax on a cold surface is a serious problem in oil production. Progress in developing more effective wax inhibitors has been impeded by the lack of an established mechanism connecting the molecular structure to inhibitor efficiency. Some comb-like polymers having long alkyl side chains are known to decrease the rate of wax formation. Among several possible mechanisms, we investigate here the incorporation-perturbation mechanism. According to this mechanism, the inhibitor molecules in oil are preferentially partitioned (incorporation) toward the wax-rich (amorphous) wax deposits (soft wax), which then serves as a perturbation to slow down the ordering transition of soft amorphous wax into more stable but problematic hard wax crystals. Indeed, molecular dynamics simulations on an effective inhibitor molecule in both the oil phase and in the amorphous wax phase support the idea that the oil-to-wax partition of the inhibitor is energetically favorable. With the inhibitor molecule embedded, the structure of wax crystal is disturbed, significantly decreasing the order and significantly lowering the cohesive energy density relative to that of the pure wax crystal, supporting the slower transition from soft wax to hard wax. Thus, in the presence of an effective wax inhibitor, crystallization (formation of hard wax) is slowed dramatically, so that there is time to flush out the soft wax with a high-pressure flow inside the pipeline. This suggests design principles for developing improved wax inhibitors. PMID:17975910

  1. Late Quaternary climate and environmental changes in a permafrost section near Igarka, Northern Siberia based on leaf wax analyses

    NASA Astrophysics Data System (ADS)

    Schaefer, Imke; Schweri, Lea; Zech, Jana; Tananaev, Nikita; Zech, Roland

    2016-04-01

    Leaf wax biomarkers, such as long chain n-alkanes and n-alkanoic acids, and their carbon isotopic composition are a promising tool for reconstructing past climate and environmental changes and gain more and more attention in paleoresearch. Here we present the results of leaf wax analyses from a permafrost outcrop at the left banks of the Yenisei River near the city of Igarka, Northern Russia. Fluvio-glacial sediments are exposed in the lower part of the outcrop and probably date back to ~60 ka. The upper part consist of aeolian sediments deposited since, overprinted by various pedogenetic processes. First results indicate a continuous contribution of deciduous trees to the vegetation during the last glacial. Compound specific deuterium and radiocarbon analyses are in progress in order to investigate changes in paleoclimate and to establish a robust chronology.

  2. Wetland plant waxes from Olduvai Gorge, Tanzania

    NASA Astrophysics Data System (ADS)

    Tamalavage, A.; Magill, C. R.; Barboni, D.; Ashley, G. M.; Freeman, K. H.

    2013-12-01

    Olduvai Gorge, northern Tanzania, exposes a Plio-Pleistocene sedimentary record that includes lake and lake-margin sediments and fossil remains of ancient plants and early humans. There are rich paleontological and cultural records at Olduvai Gorge that include thousands of vertebrate fossils and stone tools. Previous studies of plant biomarkers in lake sediments from Olduvai Gorge reveal repeated, abrupt changes in landscape dominance by woodland or grassland vegetation during the early Pleistocene, about 1.8 million years ago. However, the reconstruction of wetland vegetation in the past is limited by a dearth of published lipid signatures for modern wetland species. Here, we present lipid and isotopic data for leaf tissues from eight modern plants (i.e., sedge and Typha species) living in wetlands near Olduvai Gorge. Trends in values for molecular and leaf δ13C and average chain length (ACL) of n-alkanes in plant tissues are similar to values for underlying soils. Compound-specific δ13C values for n-alkanes C25 to C33 range between -36.4 to -23.1‰ for C3 plants and -22.3 to -19.5‰ for C4 plants. Fractionation factors between leaf and lipids, ɛ29 and ɛ33, fall within the range reported in the literature, but they differ more widely within a single plant. For C3 plants, the average difference between ɛ29 and ɛ33 is 6.5 ‰, and the difference between ɛ29 and ɛ33 for C4 plants is less than 2‰. Both plant types show a parabolic relationship between chain length and δ13C values, in which C29 typically has the most depleted value, and typically shift by 3-5‰ between alkane homologs. This pattern has not been previously reported, and could be unique for sedge lipids. If so, these data help constrain the application of plant wax biomarkers from sedges for paleo-vegetation reconstruction in paleoclimate studies and at archaeological sites.

  3. Leaf physiological processes strongly affect δH2 values of leaf wax n-alkanes in C3 and C4 grasses.

    NASA Astrophysics Data System (ADS)

    Gamarra, Bruno; Sachse, Dirk; Kahmen, Ansgar

    2013-04-01

    Leaf wax n-alkanes are naturally synthesized saturated hydrocarbons. They are synthesized as part of plant leaf cuticle as a mechanism to prevent water losses. Two of the most important features of n-alkanes are their enormous environmental persistence and terrestrial ubiquity making them a solid and reliable long-term and large-scale biomarker. Their hydrogen isotopic composition (δH2) of leaf wax n-alkanes has been traditionally related to precipitation. Leaf wax n-alkanes and their δH2 values have thus been celebrated as biomarkers to reconstruct hydrological changes. δH2 values of leaf wax n-alkanes are yet to be fully comprehended. They are basically determined by three mechanisms: (1) The δH2 value of the plant source water (2) leaf water evaporative enrichment in H2 and (3) biosynthetic fractionation and depletion in H2during their biosynthesis from leaf water. Out of these three, the exact degree by which the evaporative H2-enrichment of leaf water influences the δH2 values of leaf wax n-alkanes is still unknown. We conducted an experiment where we tested and quantified the effects of leaf water evaporative H2-enrichment on the leaf wax n-alkane δH2 values of different grass species. We grew 12 C3 and C4 grass species under controlled environmental conditions in growth chambers. The plants were exposed to 3 different levels of air relative humidity (45, 65 and 85%). These treatments were to generate different degrees of leaf water H2-enrichment in the plants. The goal of our experiment was to determine by what degree the different levels of leaf water H2-enrichment influence the δH2 values of the different C3 and C4 grass species. Additional measurements of gas exchange, evapotranspiration and leaf length and area accompanied the isotopic analysis in order to explain species variability. Our experiments showed that leaf water evaporative H2-enrichment has a critical impact on leaf wax n-alkane δH2 values of all studied plants. The magnitude was

  4. Cannabis-induced psychosis associated with high potency "wax dabs".

    PubMed

    Pierre, Joseph M; Gandal, Michael; Son, Maya

    2016-04-01

    With mounting evidence that the risk of cannabis-induced psychosis may be related to both dose and potency of tetrahydrocannbinol (THC), increasing reports of psychosis associated with cannabinoids containing greater amounts of THC are anticipated. We report two cases of emergent psychosis after using a concentrated THC extract known as cannabis "wax," "oil," or "dabs" raising serious concerns about its psychotic liability. Although "dabbing" with cannabis wax is becoming increasingly popular in the US for both recreational and "medicinal" intentions, our cases raise serious concerns about its psychotic liability and highlight the importance of understanding this risk by physicians recommending cannabinoids for purported medicinal purposes. PMID:26876313

  5. Cannabis-induced psychosis associated with high potency "wax dabs".

    PubMed

    Pierre, Joseph M; Gandal, Michael; Son, Maya

    2016-04-01

    With mounting evidence that the risk of cannabis-induced psychosis may be related to both dose and potency of tetrahydrocannbinol (THC), increasing reports of psychosis associated with cannabinoids containing greater amounts of THC are anticipated. We report two cases of emergent psychosis after using a concentrated THC extract known as cannabis "wax," "oil," or "dabs" raising serious concerns about its psychotic liability. Although "dabbing" with cannabis wax is becoming increasingly popular in the US for both recreational and "medicinal" intentions, our cases raise serious concerns about its psychotic liability and highlight the importance of understanding this risk by physicians recommending cannabinoids for purported medicinal purposes.

  6. A modified technique for fabricating a mirror image wax pattern for an auricular prosthesis.

    PubMed

    Gajdhar, Shaiq; Gajdhar, Sajda Khan; Salakalakonda, Srikanth Reddy; Vasthare, Abubakkar

    2015-01-01

    This article describes a technique for fabricating a wax pattern for an auricular prosthesis by tracing the shape of a sliced cast of the contralateral ear at an interval of 1-mm and transferring the shape of each 1-mm slice to a similar dimension modeling wax sheet. In this way, slices of modeling wax are obtained, which can be reversed and placed over the previous slice to produce a mirror image wax pattern of the contralateral ear. PMID:25277032

  7. Structural-mechanical model of wax crystal networks—a mesoscale cellular solid approach

    NASA Astrophysics Data System (ADS)

    Miyazaki, Yukihiro; Marangoni, Alejandro G.

    2014-04-01

    Mineral waxes are widely used materials in industrial applications; however, the relationship between structure and mechanical properties is poorly understood. In this work, mineral wax-oil networks were characterized as closed-cell cellular solids, and differences in their mechanical response predicted from structural data. The systems studied included straight-chain paraffin wax (SW)-oil mixtures and polyethylene wax (PW)-oil mixtures. Analysis of cryogenic-SEM images of wax-oil networks allowed for the determination of the length (l) and thickness (t) of the wax cell walls as a function of wax mass fraction (Φ). A linear relationship between t/l and Φ (t/l ˜ Φ 0.89) suggested that wax-oil networks were cellular solids of the closed-cell type. However, the scaling behavior of the elastic modulus with the volume fraction of solids did not agree with theoretical predictions, yielding the same scaling exponent, μ = 0.84, for both waxes. This scaling exponent obtained from mechanical measurements could be predicted from the scaling behavior of the effective wax cell size as a function of wax mass fraction in oil obtained by cryogenic scanning electron microscopy. Microscopy studies allowed us to propose that wax-oil networks are structured as an ensemble of close-packed spherical cells filled with oil, and that it is the links between cells that yield under simple uniaxial compression. Thus, the Young’s moduli for the links between cells in SW and PW wax systems could be estimated as E L (SW) = 2.76 × 109 Pa and E L (PW) = 1.64 × 109 Pa, respectively. The structural parameter responsible for the observed differences in the mechanical strength between the two wax-oil systems is the size of the cells. Polyethylene wax has much smaller cell sizes than the straight chain wax and thus displays a higher Young’s modulus and yield stress.

  8. Clinically based diagnostic wax-up for optimal esthetics: the diagnostic mock-up.

    PubMed

    Simon, Harel; Magne, Pascal

    2008-05-01

    A diagnostic wax-up can enhance the predictability of treatment by modeling the desired result in wax prior to treatment. It is critical to correlate the wax-up to the patient to avoid a result that appears optimal on the casts but does not correspond to the patient's smile. This article reviews the applications and techniques for clinically based diagnostic wax-up, and focuses on the diagnostic mock-up philosophy as a means to obtain predictable esthetics and function.

  9. An additive solution to the problem of wax settling in diesel fuels

    SciTech Connect

    Brown, G.I.; Tack, R.D.; Chandler, J.E

    1988-01-01

    Wax formed in cold diesel fuels can settle, causing fuel storage and distribution problems and unexpected vehicle failures. The extent of these wax settling problems depends upon fuel, storage conditions, and the design of vehicle fuel systems. New Wax Anti-settling Flow Improvers, WAFI, reduce crystal sizes and keep wax dispersed in the fuel. Improved performance of cold fuels treated with WAFI has been demonstrated in storage tests, a diesel fuel rig, and in diesel trucks on a cold climate chassis dynamometer.

  10. Impact of sweet sorghum cuticular waxes (SSCW) on acetone-butanol-ethanol fermentation using Clostridium acetobutylicum ABE1201.

    PubMed

    Cai, Di; Chang, Zhen; Wang, Chengyu; Ren, Wenqiang; Wang, Zheng; Qin, Peiyong; Tan, Tianwei

    2013-12-01

    The effect of cuticular waxes of sweet sorghum stem on acetone-butanol-ethanol (ABE) fermentation process was investigated. About 22.9% of butanol and 25.4% of ABE were decreased with fermentation period extended when SSCW was added. The inhibition of SSCW militate against both acidogenesis and solventogenesis phase, which were inconsistent with the inhibition of lignocellulose hydrolysate. Further studies on the composition of SSCW were performed. Regulations of inhibition with different carbon chain length of main compositions of SSCW on ABE fermentation were also investigated.

  11. Wax-incorporated emulsion gel beads of calcium pectinate for intragastric floating drug delivery.

    PubMed

    Sriamornsak, Pornsak; Asavapichayont, Panida; Nunthanid, Jurairat; Luangtana-Anan, Manee; Limmatvapirat, Sontaya; Piriyaprasarth, Suchada

    2008-01-01

    The purpose of this study was to prepare wax-incorporated pectin-based emulsion gel beads using a modified emulsion-gelation method. The waxes in pectin-olive oil mixtures containing a model drug, metronidazole, were hot-melted, homogenized and then extruded into calcium chloride solution. The beads formed were separated, washed with distilled water and dried for 12 h. The influence of various types and amounts of wax on floating and drug release behavior of emulsion gel beads of calcium pectinate was investigated. The drug-loaded gel beads were found to float on simulated gastric fluid if the sufficient amount of oil was used. Incorporation of wax into the emulsion gel beads affected the drug release. Water-soluble wax (i.e. polyethylene glycol) increased the drug release while other water-insoluble waxes (i.e. glyceryl monostearate, stearyl alcohol, carnauba wax, spermaceti wax and white wax) significantly retarded the drug release. Different waxes had a slight effect on the drug release. However, the increased amount of incorporated wax in the formulations significantly sustained the drug release while the beads remained floating. The results suggest that wax-incorporated emulsion gel beads could be used as a carrier for intragastric floating drug delivery. PMID:18459055

  12. Epicuticular waxes on onion leaves and associated resistance to onion thrips

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural variation exists for amounts and types of epicuticular waxes on onion foliage. Wild-type onion possesses copious amounts of these waxes and is often referred to as “waxy”. The recessively inherited “glossy” phenotype has significantly less wax relative to waxy types and shows resistance to o...

  13. Influence of Conventional and Digital Wax-ups on Axial Tooth Contour.

    PubMed

    Abduo, Jaafar; Bennamoun, Mohammed; Tennant, Marc

    2015-01-01

    The aim of this study was to evaluate the impact of conventional and digital diagnostic wax-up on the axial tooth contour. Dental models of 15 patients were collected. Each model received conventional wax-up and digital wax-up. The conventional wax-up was based on tooth modification with dental wax on actual models. The digital wax-up involved fitting an average tooth form on virtual pretreatment models. Each wax-up model was digitally superimposed on the corresponding pretreatment model. For each modified tooth, analysis planes were extracted at three locations: mesial line angle, midtooth, and distal line angle. The impact of the following variables was evaluated: interarch location (maxilla vs mandible), intra-arch location (anterior vs posterior), tooth category (incisors, canines, premolars, and molars), and tooth location (midtooth vs line angle). The axial contour of the modified teeth increased after each wax-up, and this increase was directly proportional to the distance from the gingival margin. There is a clear tendency for the digital wax-up to cause a greater contour increase than the conventional wax-up. The anterior teeth were associated with a greater tooth contour increase than posterior teeth and the contour of the molars was the least affected. Although the conventional wax-up contour alteration was significantly less than for the digital wax-up, the actual difference was minimal.

  14. Wax-incorporated emulsion gel beads of calcium pectinate for intragastric floating drug delivery.

    PubMed

    Sriamornsak, Pornsak; Asavapichayont, Panida; Nunthanid, Jurairat; Luangtana-Anan, Manee; Limmatvapirat, Sontaya; Piriyaprasarth, Suchada

    2008-01-01

    The purpose of this study was to prepare wax-incorporated pectin-based emulsion gel beads using a modified emulsion-gelation method. The waxes in pectin-olive oil mixtures containing a model drug, metronidazole, were hot-melted, homogenized and then extruded into calcium chloride solution. The beads formed were separated, washed with distilled water and dried for 12 h. The influence of various types and amounts of wax on floating and drug release behavior of emulsion gel beads of calcium pectinate was investigated. The drug-loaded gel beads were found to float on simulated gastric fluid if the sufficient amount of oil was used. Incorporation of wax into the emulsion gel beads affected the drug release. Water-soluble wax (i.e. polyethylene glycol) increased the drug release while other water-insoluble waxes (i.e. glyceryl monostearate, stearyl alcohol, carnauba wax, spermaceti wax and white wax) significantly retarded the drug release. Different waxes had a slight effect on the drug release. However, the increased amount of incorporated wax in the formulations significantly sustained the drug release while the beads remained floating. The results suggest that wax-incorporated emulsion gel beads could be used as a carrier for intragastric floating drug delivery.

  15. Hyperspectral visible-near infrared imaging for the detection of waxed rice

    NASA Astrophysics Data System (ADS)

    Zhao, Mantong

    2014-11-01

    Presently, unscrupulous traders in the market use the industrial wax to wax the rice. The industrial wax is a particularly hazardous substance. Visible-near infrared hyperspectral images (400-1,000 nm) can be used for the detection of the waxed rice and the non-waxed rice. This study was carried out to find effective testing methods based on the visible-near infrared imaging spectrometry to detect whether the rice was waxed or not. An imaging spectroscopy system was assembled to acquire hyperspectral images from 80 grains of waxed rice and 80 grains of non-waxed rice over visible and near infrared spectral region. Spectra of 100 grains of rice were analyzed by principal component analysis (PCA) to extract the information of hyperspectral images. PCA provides an effective compressed representation of the spectral signal of each pixel in the spectral domain. We used PCA to acquire the effective wavelengths from the spectra. Based on the effective wavelengths, the predict models were set up by using partial least squares (PLS) analysis and linear discriminant analysis (LDA). Also, compared with the PLS of 80% for the waxed rice and 86.7% for the non-waxed rice detection rate, LDA gives 93.3% and 96.7% detection rate. The results demonstrated that the LDA could detect the waxed rice better, while illustrating the hyperspectral imaging technique with the visible-near infrared region could be a reliable method for the waxed rice detection.

  16. Leaf waxes, compound-specific D/H and 14C analyses in the Loess Paleosol Sequence Möhlin, Switzerland

    NASA Astrophysics Data System (ADS)

    Wüthrich, Lorenz; Bliedtner, Marcel; Kathrin Schäfer, Imke; Zech, Jana; Gaar, Dorian; Preusser, Frank; Zech, Roland

    2016-04-01

    Leaf waxes, such as long-chain n-alkanes and n-alkanoic acids, and their D/H isotopic composition, are increasingly used for paleoenvironmental and -climate reconstructions. Recent technological innovations now also allow to perform radiocarbon analyses on leaf waxes. For this study, we analyzed leaf waxes and their δD and 14C composition in the 7 m Loess Paleosol Sequence Möhlin, Switzerland. The chain length patterns in the upper part of the profile indicate n-alkane contribution from deciduous trees, while the underlying loess is dominated by inputs from grasses and herbs. Our δD record does not show depleted, glacial values compared to the Holocene, as we had expected in analogy to the Greenland ice core records. Values are most enriched at 1 m depth, i.e. well below the topsoil. Further research is needed to disentangle source effects and evapotranspirative enrichment, before the δD record can be interpreted robustly. Our radiocarbon ages for the leaf waxes are in very good agreement with independent age control based on luminescence ages, corroborating that massive loess accumulation occurred already at 35 ka. Only the uppermost 3 m were deposited during the last glacial maximum.

  17. Environmental controls on the 2H/1H values of terrestrial leaf waxes in the eastern Canadian Arctic

    NASA Astrophysics Data System (ADS)

    Shanahan, Timothy M.; Hughen, Konrad A.; Ampel, Linda; Sauer, Peter E.; Fornace, Kyrstin

    2013-10-01

    The hydrogen isotope composition of plant waxes preserved in lacustrine sediments is a potentially valuable tool for reconstructing paleoenvironmental changes in the Arctic. However, in contrast to the mid- and low-latitudes, significantly less effort has been directed towards understanding the factors controlling D/H fractionation in high latitude plant waxes and the impact of these processes on the interpretation of sedimentary leaf wax δD records. To better understand these processes, we examined the D/H ratios of long chain fatty acids in lake surface sediments spanning a temperature and precipitation gradient on Baffin Island in the eastern Canadian Arctic. D/H ratios of plant waxes increase with increasing temperature and aridity, with values ranging from -240‰ to -160‰ over the study area. Apparent fractionation factors between n-alkanoic acids in Arctic lake sediments and precipitation(εFA-ppt) are less negative than those of mid-latitude lakes and modern plants by 25‰ to 65‰, consistent with n-alkane data from modern Arctic plants (Yang et al., 2011). Furthermore, εFA-ppt values from Arctic lakes become systematically more positive with increasing evaporation, in contrast to mid-latitude sites, which show little to no change in fractionation with aridity. These data are consistent with enhanced water loss and isotope fractionation at higher latitude in the Arctic summer, when continuous sunlight supports increased daily photosynthesis. The dominant control on δDFA variations on Baffin Island is temperature. However, changing εFA-ppt result in steeper δDFA-temperature relationships than observed for modern precipitation. The application of this δDFA-based paleotemperature calibration to existing δDFA records from Baffin Island produces much more realistic changes in late Holocene temperature and highlights the importance of these effects in influencing the interpretation of Arctic δDFA records. A better understanding of the controls on

  18. Integrating Science in Your Classroom: Wax On, Wane Off

    ERIC Educational Resources Information Center

    Cowens, John

    2006-01-01

    The changing figures of the waxing and waning moon are among the most conspicuous of celestial phenomena and were some of the first to be understood. This paper describes a classroom activity designed to teach children about the phases of the moon.

  19. Interior. Apparatus on table by door used for metalplating wax ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior. Apparatus on table by door used for metal-plating wax discs in order to make a steel master for use in mass production of phonograph records. Process used primarily from 1915 to 1928. - Thomas A. Edison Laboratories, Building No. 2, Main Street & Lakeside Avenue, West Orange, Essex County, NJ

  20. Variation for epicuticular waxes and thrips resistance in onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Onion thrips (Thrips tabaci) and thrips-vectored Iris Yellow Spot Virus (IYSV) routinely cause significant losses to the bulb and seed crops of onion. Both pests have become more problematic as global temperatures rise. Natural variation exists in onion for amounts and types of epicuticular waxes on...

  1. Uncovered secret of a Vasseur-Tramond wax model.

    PubMed

    Pastor, J F; Gutiérrez, B; Montes, J M; Ballestriero, R

    2016-01-01

    The technique of anatomical wax modelling reached its heyday in Italy during the 18th century, through a fruitful collaboration between sculptors and anatomists. It soon spread to other countries, and prestigious schools were created in England, France, Spain and Austria. Paris subsequently replaced Italy as the major centre of manufacture, and anatomical waxes were created there from the mid-19th century in workshops such as that of Vasseur-Tramond. This workshop began to sell waxes to European Faculties of Medicine and Schools of Surgery around 1880. Little is known of the technique employed in the creation of such artefacts as this was deemed a professional secret. To gain some insight into the methods of construction, we have studied a Vasseur-Tramond wax model in the Valladolid University Anatomy Museum, Spain, by means of multi-slice computerised tomography and X-ray analysis by means of environmental scanning electron microscopy. Scanning electron microscopy was used to examine the hair. These results have revealed some of the methods used to make these anatomical models and the materials employed.

  2. 75 FR 80843 - Petroleum Wax Candles From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ....2(f)). Background The Commission instituted this review on July 1, 2010 (75 FR 38121) and determined on October 4, 2010 that it would conduct an expedited review (75 FR 63200, October 14, 2010). The... COMMISSION Petroleum Wax Candles From China Determination On the basis of the record \\1\\ developed in...

  3. 75 FR 38121 - Petroleum Wax Candles From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ... from China (51 FR 30686). Following first five-year reviews by Commerce and the Commission, effective... candles from China (64 FR 51514). Following second five-year reviews by Commerce and the Commission... petroleum wax candles from China (70 FR 56890, September 29, 2005). The Commission is now conducting a...

  4. Mathematical modeling of wax deposition in oil pipeline systems

    SciTech Connect

    Svendsen, J.A. . Dept. of Chemical Engineering)

    1993-08-01

    Deposition of wax on the wall of oil pipelines is often regarded as a problem since the tube diameter is reduced. Consequently, more power is needed to force the same amount of oil through the system. A mathematical model for quantitative prediction of wax deposition for each hydrocarbon component has been developed. Each component is characterized by weight fraction, heat of fusion, and melting point temperature. A model explains how a phase transition in the flow from liquid oil to waxy crystals may create a local density gradient and mass flux, which depends on the local temperature gradient. The model predicts that wax deposition can be considerably reduced even when the wall temperature is below the wax appearance point, provided the liquid/solid phase transition, expressed by the change in moles of liquid with temperature, is small at the wall temperature. Deposition as function of time has been obtained as a solution of differential equations derived from the principles of mass and energy conservation and the laws of diffusion.

  5. Lubricant base oil and wax processing. [Glossary included

    SciTech Connect

    Sequeira, A. Jr.

    1994-01-01

    This book provides state-of-the-art information on all processes currently used to manufacture lubricant base oils and waxes. It furnishes helpful lists of conversion factors, construction cost data, and process licensors, as well as a glossary of essential petroleum processing terms.

  6. Epicuticular Wax in Developing Olives (Olea europaea) Is Highly Dependent upon Cultivar and Fruit Ripeness.

    PubMed

    Vichi, Stefania; Cortés-Francisco, Nuria; Caixach, Josep; Barrios, Gonçal; Mateu, Jordi; Ninot, Antonia; Romero, Agustí

    2016-08-01

    The epicuticular wax (EW) layer is located on the surface of most plant organs. It provides the cuticle with most of its properties and is the primary barrier against biotic and abiotic stress. Despite the importance of Olea europaea cultivation, few studies have characterized the EW covering leaves and olives, which could be involved in resistance to both infection and environmental conditions. In the present study, wide-ranging screening was carried out using direct-injection electrospray ionization coupled to high-resolution mass spectrometry to analyze EW in developing olives of nine varieties. The proportions of EW fractions [wax esters (WEs), diacylglycerols, triacylglycerols (TAGs), triterpenic acids, and aldehydes] strongly depended upon the olive cultivar and, in only a few cases, were influenced by the sampling date. The specific compositions of the major fractions, WEs and TAGs, were strictly related to the cultivar, while the degree of unsaturation and chain length of the WEs evolved throughout the 4 weeks prior to the olive turning color. PMID:27403567

  7. The texture, sensory properties and stability of cookies prepared with wax oleogels.

    PubMed

    Yılmaz, Emin; Öğütcü, Mustafa

    2015-04-01

    Shortening is the essential component of high quality baked foods. Its effects on dough structure formation and the desired final product attributes depend mostly on its solid fat content and β' crystalline polymorphs. Saturated and trans fatty acids present in shortening pose some important negative health considerations. Hence, alternative plastic fats with lower or zero quantity of saturated and trans fatty acids are in high demand. Oleogels are gel networks of liquid edible oils with no trans and very low saturated fatty acids. In this study, sunflower wax (SW) and beeswax (BW) oleogels of hazelnut oil were used in cookie preparation against commercial bakery shortening (CBS) as the control, to compare the textural, sensory and stability properties of the cookies. The basic chemical composition, textural properties, and some physical attributes of the cookies were compared. Sensory texture/flavor profile analysis (T/FPA) and consumer hedonic tests were also accomplished. Furthermore, the changes in cookie texture and stability were monitored during 30 day storage at room temperature. It was found out that in almost all properties, the oleogel cookies resembled CBS cookies. T/FPA results present detailed data for literature. Consumer hedonic scores indicated that oleogel cookies were better than CBS cookies and were also well accepted by consumers. Wax oleogels can be used as cookie shortening successfully.

  8. Epicuticular Wax in Developing Olives (Olea europaea) Is Highly Dependent upon Cultivar and Fruit Ripeness.

    PubMed

    Vichi, Stefania; Cortés-Francisco, Nuria; Caixach, Josep; Barrios, Gonçal; Mateu, Jordi; Ninot, Antonia; Romero, Agustí

    2016-08-01

    The epicuticular wax (EW) layer is located on the surface of most plant organs. It provides the cuticle with most of its properties and is the primary barrier against biotic and abiotic stress. Despite the importance of Olea europaea cultivation, few studies have characterized the EW covering leaves and olives, which could be involved in resistance to both infection and environmental conditions. In the present study, wide-ranging screening was carried out using direct-injection electrospray ionization coupled to high-resolution mass spectrometry to analyze EW in developing olives of nine varieties. The proportions of EW fractions [wax esters (WEs), diacylglycerols, triacylglycerols (TAGs), triterpenic acids, and aldehydes] strongly depended upon the olive cultivar and, in only a few cases, were influenced by the sampling date. The specific compositions of the major fractions, WEs and TAGs, were strictly related to the cultivar, while the degree of unsaturation and chain length of the WEs evolved throughout the 4 weeks prior to the olive turning color.

  9. FT Duplication Coordinates Reproductive and Vegetative Growth

    SciTech Connect

    Hsu, Chuan-Yu; Adams, Joshua P.; Kim, Hyejin; No, Kyoungok; Ma, Caiping; Strauss, Steven; Drnevich, Jenny; Wickett, Norman; Vandervelde, Lindsay; Ellis, Jeffrey D.; Rice, Brandon; Gunter, Lee E; Tuskan, Gerald A; Brunner, Amy M.; Page, Grier P.; Carlson, John E.; DePamphilis, Claude; Luthe, Dawn S.; Yuceer, Cetin

    2011-01-01

    Annual plants grow vegetatively at early developmental stages and then transition to the reproductive stage, followed by senescence in the same year. In contrast, after successive years of vegetative growth at early ages, woody perennial shoot meristems begin repeated transitions between vegetative and reproductive growth at sexual maturity. However, it is unknown how these repeated transitions occur without a developmental conflict between vegetative and reproductive growth. We report that functionally diverged paralogs FLOWERING LOCUS T1 (FT1) and FLOWERING LOCUS T2 (FT2), products of whole-genome duplication and homologs of Arabidopsis thaliana gene FLOWERING LOCUS T (FT), coordinate the repeated cycles of vegetative and reproductive growth in woody perennial poplar (Populus spp.). Our manipulative physiological and genetic experiments coupled with field studies, expression profiling, and network analysis reveal that reproductive onset is determined by FT1 in response to winter temperatures, whereas vegetative growth and inhibition of bud set are promoted by FT2 in response to warm temperatures and long days in the growing season. The basis for functional differentiation between FT1 and FT2 appears to be expression pattern shifts, changes in proteins, and divergence in gene regulatory networks. Thus, temporal separation of reproductive onset and vegetative growth into different seasons via FT1 and FT2 provides seasonality and demonstrates the evolution of a complex perennial adaptive trait after genome duplication.

  10. The SHINE Clade of AP2 Domain Transcription Factors Activates Wax Biosynthesis, Alters Cuticle Properties, and Confers Drought Tolerance when Overexpressed in ArabidopsisW⃞

    PubMed Central

    Aharoni, Asaph; Dixit, Shital; Jetter, Reinhard; Thoenes, Eveline; van Arkel, Gert; Pereira, Andy

    2004-01-01

    The interface between plants and the environment plays a dual role as a protective barrier as well as a medium for the exchange of gases, water, and nutrients. The primary aerial plant surfaces are covered by a cuticle, acting as the essential permeability barrier toward the atmosphere. It is a heterogeneous layer composed mainly of lipids, namely cutin and intracuticular wax with epicuticular waxes deposited on the surface. We identified an Arabidopsis thaliana activation tag gain-of-function mutant shine (shn) that displayed a brilliant, shiny green leaf surface with increased cuticular wax compared with the leaves of wild-type plants. The gene responsible for the phenotype encodes one member of a clade of three proteins of undisclosed function, belonging to the plant-specific family of AP2/EREBP transcription factors. Overexpression of all three SHN clade genes conferred a phenotype similar to that of the original shn mutant. Biochemically, such plants were altered in wax composition (very long fatty acid derivatives). Total cuticular wax levels were increased sixfold in shn compared with the wild type, mainly because of a ninefold increase in alkanes that comprised approximately half of the total waxes in the mutant. Chlorophyll leaching assays and fresh weight loss experiments indicated that overexpression of the SHN genes increased cuticle permeability, probably because of changes in its ultrastructure. Likewise, SHN gene overexpression altered leaf and petal epidermal cell structure, trichome number, and branching as well as the stomatal index. Interestingly, SHN overexpressors displayed significant drought tolerance and recovery, probably related to the reduced stomatal density. Expression analysis using promoter-β-glucuronidase fusions of the SHN genes provides evidence for the role of the SHN clade in plant protective layers, such as those formed during abscission, dehiscence, wounding, tissue strengthening, and the cuticle. We propose that these diverse

  11. Low severity upgrading of F-T waxes with solid superacids. Quarterly report, January 1995--March 1995

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1995-04-06

    In this quarter we studied the effect of hydrogen pressure, and of sulfur and nitrogen containing compounds on the isomerization and hydrocracking of n-hexadecane using a Pt/ZrO{sub 2}/SO{sub 4} catalyst. The reactions were carried out at 300{degrees}C and hydrogen pressures between 50 and 500 psig. Increasing hydrogen pressure resulted in increased conversion and increased hydrocracking. Nitrogen containing compounds had a greater inhibiting effect on the conversion of n-hexadecane than sulfur-containing compounds. The reaction of diphenylmethane in air at 25{degrees}C and in the presence of sulfated zirconia was studied as a possible means to characterize the protonic acidity of solid superacids.

  12. Transcutaneous DNA immunization following waxing-based hair depilation

    PubMed Central

    Sloat, Brian R.; Kiguchi, Kaoru; Xiao, Gang; DiGiovanni, John; Maury, Wendy; Cui, Zhengrong

    2011-01-01

    Transcutaneous DNA immunization is an attractive immunization approach. Previously, we reported that transcutaneous immunization by applying plasmid DNA onto a skin area wherein the hair follicles had been induced into growth stage by ‘cold’ waxing-based hair plucking significantly enhanced the resultant immune responses. In the present study, using a plasmid that encodes the Bacillus anthracis protective antigen (PA63) gene fragment, it was shown that the anti-PA63 antibody responses induced by applying the plasmid onto a skin area where the hair was plucked by ‘warm’ waxing were significantly stronger than by ‘cold’ waxing, very likely because the ‘warm’ waxing-based hair depilation significantly i) enhanced the uptake (or retention) of the plasmid in the application area and ii) enhanced the expression of the transfected gene in the follicular and interfollicular epidermis in the skin. The antibody response induced by transcutaneous DNA immunization was hair cycle dependent, because the plasmid needed to be applied within 5 days after the hair plucking to induce a strong antibody response. The antibody responses were not affected by whether the expressed PA63 protein, as an antigen, was secreted or cell surface bound. Finally, this strategy of enhancing the immune responses induced by transcutaneous DNA immunization following ‘warm’ waxing-based hair depilation was not limited to the PA63 as an antigen, because immunization with a plasmid that encodes the HIV-1 env gp160 gene induced a strong anti-gp160 response as well. Transcutaneous DNA immunization by modifying the hair follicle cycle may hold a great promise in inducing strong and functional immune responses. PMID:21907253

  13. Increased production of wax esters in transgenic tobacco plants by expression of a fatty acid reductase:wax synthase gene fusion.

    PubMed

    Aslan, Selcuk; Hofvander, Per; Dutta, Paresh; Sun, Chuanxin; Sitbon, Folke

    2015-12-01

    Wax esters are hydrophobic lipids consisting of a fatty acid moiety linked to a fatty alcohol with an ester bond. Plant-derived wax esters are today of particular concern for their potential as cost-effective and sustainable sources of lubricants. However, this aspect is hampered by the fact that the level of wax esters in plants generally is too low to allow commercial exploitation. To investigate whether wax ester biosynthesis can be increased in plants using transgenic approaches, we have here exploited a fusion between two bacterial genes together encoding a single wax ester-forming enzyme, and targeted the resulting protein to chloroplasts in stably transformed tobacco (Nicotiana benthamiana) plants. Compared to wild-type controls, transgenic plants showed both in leaves and stems a significant increase in the total level of wax esters, being eight-fold at the whole plant level. The profiles of fatty acid methyl ester and fatty alcohol in wax esters were related, and C16 and C18 molecules constituted predominant forms. Strong transformants displayed certain developmental aberrations, such as stunted growth and chlorotic leaves and stems. These negative effects were associated with an accumulation of fatty alcohols, suggesting that an adequate balance between formation and esterification of fatty alcohols is crucial for a high wax ester production. The results show that wax ester engineering in transgenic plants is feasible, and suggest that higher yields may become achieved in the near future.

  14. Leaf water and plant wax hydrogen isotopes in a European sample network

    NASA Astrophysics Data System (ADS)

    Nelson, D. B.; Kahmen, A.

    2014-12-01

    The hydrogen isotopic composition of plant waxes in sediments is now routinely used as a hydroclimate proxy. This application is based largely on empirical calibrations that have demonstrated continental-scale correlations between source water and lipid hydrogen isotope values. But at smaller spatial scales and for individual locations it is increasingly recognized that factors that modify apparent fractionation between source water and leaf lipid hydrogen isotope values must also be considered. Isotopic enrichment of leaf water during transpiration is key among these secondary factors, and is itself sensitive to changes in hydroclimate. Leaf water enrichment also occurs prior to photosynthetic water uptake, and is therefore independent from cellular-level biomarker synthesis. Recent advances in theory have permitted mechanistic models to be developed that can be used to predict the mean leaf water hydrogen and oxygen isotope composition from readily available meteorological variables. This permits global-scale isoscape maps of leaf water isotopic composition and enrichment above source water to be generated, but these models have not been widely validated at continental spatial scales. We have established a network of twenty-one sites across Europe where we are sampling for leaf-, xylem-, and soil-water isotopes (H and O) at approximately 5-week intervals over the summer growing season. We augment the sample set with weekly to monthly precipitation samples and early- and late-season plant wax lipid samples. Collaborators at each site are conducting the sampling, and most sites are members of the FLUXNET tower network that also record high-resolution meteorological data. We present information on the implementation of the network and preliminary results from the 2014 summer season. The complete dataset will be used to track the evolution of water isotopes from source to leaf water and from leaf water to lipid hydrogen across diverse environments. This will provide

  15. DEWAX-mediated transcriptional repression of cuticular wax biosynthesis in Arabidopsis thaliana.

    PubMed

    Suh, Mi Chung; Go, Young Sam

    2014-06-06

    The aerial parts of plants are covered with a cuticular wax layer, which is the first barrier between a plant and its environment. Although cuticular wax deposition increases more in the light than in the dark, little is known about the molecular mechanisms underlying the regulation of cuticular wax biosynthesis. Recently DEWAX (Decrease Wax Biosynthesis) encoding an AP2/ERF transcription factor was found to be preferentially expressed in the epidermis and induced by darkness. Wax analysis of the dewax knockout mutant, wild type, and DEWAX overexpression lines (OX) indicates that DEWAX is a negative regulator of cuticular wax biosynthesis. DEWAX represses the expression of wax biosynthetic genes CER1, LACS2, ACLA2, and ECR via direct interaction with their promoters. Cuticular wax biosynthesis is negatively regulated twice a day by the expression of DEWAX; throughout the night and another for stomata closing. Taken together, it is evident that DEWAX-mediated negative regulation of the wax biosynthetic genes plays role in determining the total wax loads produced in Arabidopsis during daily dark and light cycles. In addition, significantly higher levels of DEWAX transcripts in leaves than stems suggest that DEWAX-mediated transcriptional repression might be involved in the organ-specific regulation of total wax amounts on plant surfaces.

  16. FT-IR spectroscopy of lipoproteins—A comparative study

    NASA Astrophysics Data System (ADS)

    Krilov, Dubravka; Balarin, Maja; Kosović, Marin; Gamulin, Ozren; Brnjas-Kraljević, Jasminka

    2009-08-01

    FT-IR spectra, in the frequency region 4000-600 cm -1, of four major lipoprotein classes: very low density lipoprotein (VLDL), low density lipoprotein (LDL) and two subclasses of high density lipoproteins (HDL 2 and HDL 3) were analyzed to obtain their detailed spectral characterization. Information about the protein domain of particle was obtained from the analysis of amide I band. The procedure of decomposition and curve fitting of this band confirms the data already known about the secondary structure of two different apolipoproteins: apo A-I in HDL 2 and HDL 3 and apo B-100 in LDL and VLDL. For information about the lipid composition and packing of the particular lipoprotein the well expressed lipid bands in the spectra were analyzed. Characterization of spectral details in the FT-IR spectrum of natural lipoprotein is necessary to study the influence of external compounds on its structure.

  17. Seasonal variations in compound-specific leaf-wax lipid δD values and their relationship to environmental factors and plant physiological processes

    NASA Astrophysics Data System (ADS)

    Sachse, D.; Gleixner, G.; Buchmann, N.; Kahmen, A.

    2008-12-01

    Lipids are present in high concentrations in the leaf waxes of deciduous plants and are the final products of plant biosynthesis. Their hydrogen isotopic composition (δD) should therefore provide a time- integrated value of the leaf water used for biosynthesis and in turn the environmental and physiological factors determining leaf water enrichment. Due to the stability of lipids, their stable isotopic composition in soils and sediments could become a powerful tool to asses (paleo)hydrologic conditions. However, the relative importances of plant physiology and climatic influences as well as the timeframe over which the lipid δD value integrates these factors have not been investigated systematically. Here we explore how changes in environmental parameters and plant physiological processes over a growing season are recorded in compound-specific hydrogen isotope ratios of individual leaf-wax lipids. We sampled soil water, leaf water at dawn and midday, water vapor for hydrogen isotopic analysis, leaves for lipid analysis and recorded a number of environmental parameters (temperature, relative humidity, vapor pressure deficit among others) and plant physiological data (stomatal conductance, transpiration, photosynthetic rate) weekly over the two month growing season of wheat grass. We analyze the relative importance of plant physiological processes and environmental factors in determining leaf water enrichment and the leaf wax lipid isotopic composition. The isotopic composition of soil water and leaf water at dawn showed similar trends and increased over the growing season with short-term variations of about 40‰. Leaf wax lipid δD values varied only on the order of 20‰ over the growing season following a similar trend as soil water and leaf water at dawn. We observe a 20‰ decrease in lipid δD values only a week after a significant 40‰ decrease in the soil and leaf water isotopic composition, due to a strong rain event. These results suggest, that leaf-wax

  18. Preparation and characterization of carnauba wax nanostructured lipid carriers containing benzophenone-3.

    PubMed

    Lacerda, S P; Cerize, N N P; Ré, M I

    2011-08-01

    Nanostructured lipid carriers (NLCs) are potential active delivery systems based on mixtures of solid lipids and liquid oil. In this paper, aqueous dispersions of NLCs were prepared by a hot high-pressure homogenization technique using carnauba wax as the solid lipid and isodecyl oleate as the liquid oil. The preparation and stability parameters of benzophenone-3-loaded NLCs have been investigated concerning particle size, zeta potential and loading capacity to encapsulate benzophenone-3, a molecular sunscreen. The current investigation illustrates the effect of the composition of the lipid mixture on the entrapment efficiency, in vitro release and stability of benzophenone-3-loaded in these NLCs. A loading capacity of approximately 5% of benzophenone-3 (m(BZ-3) /m(lipids) ) was characteristic of these systems. PMID:21284656

  19. Wax Ester Analysis of Bats Suffering from White Nose Syndrome in Europe.

    PubMed

    Řezanka, Tomáš; Viden, Ivan; Nováková, Alena; Bandouchová, Hana; Sigler, Karel

    2015-07-01

    The composition of wax esters (WE) in the fur of adult greater mouse-eared bats (Myotis myotis), either healthy or suffering from white nose syndrome (WNS) caused by the psychrophilic fungus Pseudogymnoascus destructans, was investigated by high-resolution mass spectrometry analysis in the positive ion mode. Profiling of lipid classes showed that WE are the most abundant lipid class, followed by cholesterol esters, and other lipid classes, e.g., triacylglycerols and phospholipids. WE abundance in non-polar lipids was gender-related, being higher in males than in females; in individuals suffering from WNS, both male and female, it was higher than in healthy counterparts. WE were dominated by species containing 18:1 fatty acids. Fatty alcohols were fully saturated, dominated by species containing 24, 25, or 26 carbon atoms. Two WE species, 18:1/18:0 and 18:1/20:0, were more abundant in healthy bats than in infected ones. PMID:25975369

  20. A SAXS/WAXS XAFS study of crystallisation in cordierite glass.

    PubMed

    Greaves, G N; Bras, W; Oversluizen, M; Clark, S M

    2003-01-01

    New Cr X-ray absorption fine structure (XAFS) data have been combined with the results of small angle X-ray scattering (SAXS) and wide angle X-ray scattering (WAXS) experiments to probe in detail the crystallisation mechanism in cordierite (Mg2Al4Si5O18) glass doped with 0.34 mol% Cr2O3. By direct comparison with chromo-aluminate spinels (MgCr2xAl2(1 - x)O4) Cr XAFS is used to determine the composition of the devitrified Cr species. This is identified as MgCr(0.18)Al(1.82)O4, which can be directly related to the Cr content in the starting glass and as a result the total crystalline volume in the fully developed ceramic is predicted to be 4%. In situ WAXS not only reveals the presence of the spinel phase but also a silica-rich stuffed quartz phase. This grows independently of the spinel and is probably nucleated from the glass surface. From our knowledge of the compositions of both crystalline phases we are able to deduce that the SAXS contrast between the surrounding glass and the spinel crystallites is 30 times greater than that between the quartz crystallites and the glass matrix, and therefore dominates the measured scattered intensity and the SAXS invariant that is derived from it. As a consequence we are able to show that the spinel crystalline volume fraction inherent in the SAXS is in close agreement with the 4% value obtained from the Cr XAFS. Furthermore in situ SAXS reveals the gradual development of the spinel particle size and shape during heat treatment. This is conducted in the super-cooled region just above the glass transition temperature, Tg. By employing a two-step annealing process nucleation can be separated from growth and from time-resolved SAXS measurements the alumino-chromate nanocrystals are found to be closely monodispersed. Over a total time course of 600 min they grow from rough crystallites to smooth spherical particles of radius 21 +/- 2 nm, with a final density of (1.2 +/- 0.4) x 10(21) m(-3). As the process of ceramic formation

  1. The Developmental Pattern of Tomato Fruit Wax Accumulation and Its Impact on Cuticular Transpiration Barrier Properties: Effects of a Deficiency in a β-Ketoacyl-Coenzyme A Synthase (LeCER6)1[C

    PubMed Central

    Leide, Jana; Hildebrandt, Ulrich; Reussing, Kerstin; Riederer, Markus; Vogg, Gerd

    2007-01-01

    Cuticular waxes play a pivotal role in limiting transpirational water loss across the primary plant surface. The astomatous fruits of the tomato (Lycopersicon esculentum) ‘MicroTom’ and its lecer6 mutant, defective in a β-ketoacyl-coenzyme A synthase, which is involved in very-long-chain fatty acid elongation, were analyzed with respect to cuticular wax load and composition. The developmental course of fruit ripening was followed. Both the ‘MicroTom’ wild type and lecer6 mutant showed similar patterns of quantitative wax accumulation, although exhibiting considerably different water permeances. With the exception of immature green fruits, the lecer6 mutant exhibited about 3- to 8-fold increased water loss per unit time and fruit surface area when compared to the wild type. This was not the case with immature green fruits. The differences in final cuticular barrier properties of tomato fruits in both lines were fully developed already in the mature green to early breaker stage of fruit development. When the qualitative chemical composition of fruit cuticular waxes during fruit ripening was investigated, the deficiency in a β-ketoacyl-coenzyme A synthase in the lecer6 mutant became discernible in the stage of mature green fruits mainly by a distinct decrease in the proportion of n-alkanes of chain lengths > C28 and a concomitant increase in cyclic triterpenoids. This shift in cuticular wax biosynthesis of the lecer6 mutant appears to be responsible for the simultaneously occurring increase of water permeance. Changes in cutin composition were also investigated as a function of developmental stage. This integrative functional approach demonstrates a direct relationship between cuticular transpiration barrier properties and distinct chemical modifications in cuticular wax composition during the course of tomato fruit development. PMID:17468214

  2. Seasonal variation of leaf wax n-alkane production and δ(2)H values from the evergreen oak tree, Quercus agrifolia.

    PubMed

    Sachse, Dirk; Dawson, Todd E; Kahmen, Ansgar

    2015-01-01

    In order to understand the timing of leaf wax synthesis in higher plants, we analysed the variability in leaf wax n-alkane concentration, composition (expressed as average chain length (ACL)), and δ(2)Hwax values as well as plant source water δ(2)H values (xylem and leaf water) in the evergreen tree Quercus agrifolia over a period of 9 months, beginning with leaf flush. We identified three distinct periods of leaf development with the first month following leaf flush being characterized by de novo synthesis and possibly removal of n-alkanes. During the following 3 months, n-alkane concentrations increased sevenfold and δ(2)Hwax and ACL values increased, suggesting this period was the major leaf wax n-alkane formation period. During the remaining 4 months of the experiment, stable values suggest cessation of leaf wax n-alkane formation. We find that n-alkane synthesis in Q. agrifolia takes place over 4 months, substantially longer than that observed for deciduous trees. PMID:25704898

  3. The Effect of Water or Wax-based Binders on the Chemical and Morphological Characteristics of the Margin Ceramic-Framework Interface.

    PubMed

    Güler, Umut; de Queiroz, José Renato Cavalcanti; de Oliveira, Luiz Fernando Cappa; Canay, Senay; Ozcan, Mutlu

    2015-09-01

    This study evaluated the effect of binder choice in mixing ceramic powder on the chemical and morphological features between the margin ceramic-framework interfaces. Titanium and zirconia frameworks (15 x 5 x 0.5 mm3) were veneered with margin ceramics prepared with two different binders, namely a) water/conventional or b) wax-based. For each zirconia framework material, four different margin ceramics were used: a- Creation Zi (Creation Willi Geller International); b- GC Initial Zr (GC America); Triceram (Dentaurum); and d- IPS emax (voclar Vivadent). For the titanium framework, three different margin ceramics were used: a- Creation Ti (Creation Willi Geller International); b- Triceram (Dentaurum); and c- VITA Titaniumkeramik (Vita Zahnfabrik). The chemical composition of the framework-margin ceramic interface was analyzed using Energy Dispersive X-ray Spectroscopy (EDS) and porosity level was quantified within the margin ceramic using an image program (ImageJ) from four random areas (100 x 100 pixels) on each SEM image. EDS analysis showed the presence of Carbon at the margin ceramic-framework interface in the groups where wax-based binder technique was used with the concentration being the highest for the IPS emax ZirCAD group. While IPS system (IPS ZirCAD and IPS Emax) presented higher porosity concentration using wax binder, in the other groups wax-based binder reduced the porosity of margin ceramic, except for Titanium - Triceram combination. PMID:26591248

  4. Cascade synthesis of a gold nanoparticle-network polymer composite

    NASA Astrophysics Data System (ADS)

    Grubjesic, Simonida; Ringstrand, Bryan S.; Jungjohann, Katherine L.; Brombosz, Scott M.; Seifert, Sönke; Firestone, Millicent A.

    2016-01-01

    The multi-step, cascade synthesis of a self-supporting, hierarchically-structured gold nanoparticle hydrogel composite is described. The composite is spontaneously prepared from a non-covalent, lamellar lyotropic mesophase composed of amphiphiles that support the reactive constituents, a mixture of hydroxyl- and acrylate-end-derivatized PEO117-PPO47-PEO117 and [AuCl4]-. The reaction sequence begins with the auto-reduction of aqueous [AuCl4]- by PEO117-PPO47-PEO117 which leads to both the production of Au NPs and the free radical initiated polymerization and crosslinking of the acrylate end-derivatized PEO117-PPO47-PEO117 to yield a network polymer. Optical spectroscopy and TEM monitored the reduction of [AuCl4]-, formation of large aggregated Au NPs and oxidative etching into a final state of dispersed, spherical Au NPs. ATR/FT-IR spectroscopy and thermal analysis confirms acrylate crosslinking to yield the polymer network. X-ray scattering (SAXS and WAXS) monitored the evolution of the multi-lamellar structured mesophase and revealed the presence of semi-crystalline PEO confined within the water layers. The hydrogel could be reversibly swollen without loss of the well-entrained Au NPs with full recovery of composite structure. Optical spectroscopy shows a notable red shift (Δλ ~ 45 nm) in the surface plasmon resonance between swollen and contracted states, demonstrating solvent-mediated modulation of the internal NP packing arrangement.The multi-step, cascade synthesis of a self-supporting, hierarchically-structured gold nanoparticle hydrogel composite is described. The composite is spontaneously prepared from a non-covalent, lamellar lyotropic mesophase composed of amphiphiles that support the reactive constituents, a mixture of hydroxyl- and acrylate-end-derivatized PEO117-PPO47-PEO117 and [AuCl4]-. The reaction sequence begins with the auto-reduction of aqueous [AuCl4]- by PEO117-PPO47-PEO117 which leads to both the production of Au NPs and the free radical

  5. Adhesion force measurements on the two wax layers of the waxy zone in Nepenthes alata pitchers

    PubMed Central

    Gorb, Elena V.; Purtov, Julia; Gorb, Stanislav N.

    2014-01-01

    The wax coverage of the waxy zone in Nepenthes alata pitchers consists of two clearly distinguishable layers, designated the upper and lower wax layers. Since these layers were reported to reduce insect attachment, they were considered to have anti-adhesive properties. However, no reliable adhesion tests have been performed with these wax layers. In this study, pull-off force measurements were carried out on both wax layers of the N. alata pitcher and on two reference polymer surfaces using deformable polydimethylsiloxane half-spheres as probes. To explain the results obtained, roughness measurements were performed on test surfaces. Micro-morphology of both surface samples and probes tested was examined before and after experiments. Pull-off forces measured on the upper wax layer were the lowest among surfaces tested. Here, contamination of probes by wax crystals detached from the pitcher surface was found. This suggests that low insect attachment on the upper wax layer is caused primarily by the breaking off of wax crystals from the upper wax layer, which acts as a separation layer between the insect pad and the pitcher surface. High adhesion forces obtained on the lower wax layer are explained by the high deformability of probes and the particular roughness of the substrate. PMID:24889352

  6. Adhesion force measurements on the two wax layers of the waxy zone in Nepenthes alata pitchers.

    PubMed

    Gorb, Elena V; Purtov, Julia; Gorb, Stanislav N

    2014-06-03

    The wax coverage of the waxy zone in Nepenthes alata pitchers consists of two clearly distinguishable layers, designated the upper and lower wax layers. Since these layers were reported to reduce insect attachment, they were considered to have anti-adhesive properties. However, no reliable adhesion tests have been performed with these wax layers. In this study, pull-off force measurements were carried out on both wax layers of the N. alata pitcher and on two reference polymer surfaces using deformable polydimethylsiloxane half-spheres as probes. To explain the results obtained, roughness measurements were performed on test surfaces. Micro-morphology of both surface samples and probes tested was examined before and after experiments. Pull-off forces measured on the upper wax layer were the lowest among surfaces tested. Here, contamination of probes by wax crystals detached from the pitcher surface was found. This suggests that low insect attachment on the upper wax layer is caused primarily by the breaking off of wax crystals from the upper wax layer, which acts as a separation layer between the insect pad and the pitcher surface. High adhesion forces obtained on the lower wax layer are explained by the high deformability of probes and the particular roughness of the substrate.

  7. Heat transfer enhancement in a paraffin wax thermal storage system

    SciTech Connect

    Eftekhar, J.; Haji-Sheikh, A.; Lou, Y.S.

    1984-08-01

    Heat transfer enhancement in a thermal storage system consisting of vertically arranged fins between a heated and cooled horizontal finned-tube arrangement is reported. The high thermal expansion coefficient and low viscosity of paraffin wax, at temperatures above 50/sup 0/C, are utilized to induce natural convection in the liquid phase even at small thicknesses. The experimental data on the rate of production of liquid as a function of time and temperature of the hot surface is presented. The photographs of the melted zone indicate a naturally buoyant flow induced in the neighborhood of the vertical fins causes a rapid melting of the solid wax and a downdraft along the cooler solid phase surface. The heat transfer coefficient at the interface is calculated from experimentally determined instantaneous locations of the moving boundary.

  8. Solids concentration measurements in molten wax by an ultrasonic technique

    SciTech Connect

    Soong, Y.; Gamwo, I.K.; Blackwell, A.G.; Schehl, R.R.; Zarochak, M.F.

    1994-12-31

    The application of the three-phase slurry reactor system to coal liquefaction processing and chemical industries has recently received considerable attention. To design and efficiently operate a three-phase slurry reactor, the degree of dispersion of the solid (catalyst) in the reactor should be understood. The solids distribution within the reactor greatly affects its performance. An ultrasonic technique is under development for measuring solids concentration in a three-phase slurry reactor. Preliminary measurements have been made on slurries consisting of molten paraffin wax, glass beads, and nitrogen bubbles at 189 C. The data show that the velocity and attenuation of the sound are well-defined functions of the solid and gas concentrations in the molten wax.

  9. In situ nitrogen generation removes wax from flowlines

    SciTech Connect

    Khalil, C.N.

    1996-07-01

    Formation of paraffin (wax) in cold deepwater flowlines is a major problem for offshore operators of such facilities. Petrobras faces this problem continuously in its deepwater operations in the Campos basin, offshore Brazil. Since 1990, through its Petrobras Research Center (CENPES), the company has developed, extensively field tested, and recently commercialized, a novel technique for chemically removing such wax depositions. The process involves mixing and introducing to the line, two inorganic salts and organic solvents. The ensuing chemical reaction--which both generates nitrogen and heats the inside of the blocked flowline--allows the solvent to dissolve and dislodge the buildup, which is then flushed from the line. The process is called the Nitrogen Generation System (SGN). Petrobras/CENPES has recently formed a joint venture with the Brazilian service company Maritima Navegacao e Engenharia Ltda. to offer SGN services worldwide.

  10. Insect attachment on crystalline bioinspired wax surfaces formed by alkanes of varying chain lengths

    PubMed Central

    Böhm, Sandro; Jacky, Nadine; Maier, Louis-Philippe; Dening, Kirstin; Pechook, Sasha; Pokroy, Boaz; Gorb, Stanislav

    2014-01-01

    Summary The impeding effect of plant surfaces covered with three-dimensional wax on attachment and locomotion of insects has been shown previously in numerous experimental studies. The aim of this study was to examine the effect of different parameters of crystalline wax coverage on insect attachment. We performed traction experiments with the beetle Coccinella septempunctata and pull-off force measurements with artificial adhesive systems (tacky polydimethylsiloxane semi-spheres) on bioinspired wax surfaces formed by four alkanes of varying chain lengths (C36H74, C40H82, C44H90, and C50H102). All these highly hydrophobic coatings were composed of crystals having similar morphologies but differing in size and distribution/density, and exhibited different surface roughness. The crystal size (length and thickness) decreased with an increase of the chain length of the alkanes that formed these surfaces, whereas the density of the wax coverage, as well as the surface roughness, showed an opposite relationship. Traction tests demonstrated a significant, up to 30 fold, reduction of insect attachment forces on the wax surfaces when compared with the reference glass sample. Attachment of the beetles to the wax substrates probably relied solely on the performance of adhesive pads. We found no influence of the wax coatings on the subsequent attachment ability of beetles. The obtained data are explained by the reduction of the real contact between the setal tips of the insect adhesive pads and the wax surfaces due to the micro- and nanoscopic roughness introduced by wax crystals. Experiments with polydimethylsiloxane semi-spheres showed much higher forces on wax samples when compared to insect attachment forces measured on these surfaces. We explain these results by the differences in material properties between polydimethylsiloxane probes and tenent setae of C. septempunctata beetles. Among wax surfaces, force experiments showed stronger insect attachment and higher pull

  11. Determination of serotonin released from coffee wax by liquid chromatography.

    PubMed

    Kele, M; Ohmacht, R

    1996-04-12

    A simple hydrolysis and extraction method was developed for the release of serotonin (5-hydroxytryptamine) from a coffee wax sample obtained from decaffeination of coffee beans. The recoverable amount of serotonin was determined by reversed-phase high-performance liquid chromatography with gradient elution and UV detection, using the standard addition method. Different type of basic deactivated chromatographic columns were used for the separation.

  12. Effect of microwave radiation on Jayadhar cotton fibers: WAXS studies

    SciTech Connect

    Niranjana, A. R. Mahesh, S. S. Divakara, S. Somashekar, R.

    2014-04-24

    Thermal effect in the form of micro wave energy on Jayadhar cotton fiber has been investigated. Microstructural parameters have been estimated using wide angle x-ray scattering (WAXS) data and line profile analysis program developed by us. Physical properties like tensile strength are correlated with X-ray results. We observe that the microwave radiation do affect significantly many parameters and we have suggested a multivariate analysis of these parameters to arrive at a significant result.

  13. Anna Morandi's wax self-portrait with brain.

    PubMed

    Messbarger, Rebecca

    2013-01-01

    In her self-portrait in wax, eighteenth-century Bolognese anatomist and anatomical modeler Anna Morandi Manzolini (1714-1774) represented herself in sumptuous aristocratic dress while dissecting a human brain. This essay explores the scientific and symbolic meaning of the vivid self-portrayal in terms of Anna Morandi's lifework at the intersection of art and anatomical science and within the remarkable cultural context of Enlightenment Bologna that fostered her rise to international acclaim. PMID:24041277

  14. Determination of serotonin released from coffee wax by liquid chromatography.

    PubMed

    Kele, M; Ohmacht, R

    1996-04-12

    A simple hydrolysis and extraction method was developed for the release of serotonin (5-hydroxytryptamine) from a coffee wax sample obtained from decaffeination of coffee beans. The recoverable amount of serotonin was determined by reversed-phase high-performance liquid chromatography with gradient elution and UV detection, using the standard addition method. Different type of basic deactivated chromatographic columns were used for the separation. PMID:8680597

  15. Leaf epicuticular waxes as proxies for paleoenvironmental conditions

    NASA Astrophysics Data System (ADS)

    Schaefer, Imke; Zech, Jana; Lanny, Verena; Eglinton, Timothy; Zech, Roland

    2015-04-01

    Long-chain n-alkanes and n-carboxylic acids are essential constituents of leaf waxes and can be used for the reconstruction of the paleovegetation and paleoclimate (e.g. Zech et al. 2013a). However, more research is needed to assess the full potential of these leaf wax biomarkers. Here we present results from a study on a transect from Southern Germany to Sweden. Our resuts show that litter and soils under deciduous trees have a dominance of the C27 n-alkane and the C28 n-carboxylic acid. Conifers are characterized by the dominance of the C29 n-alkane and the C22 and C24 n-carboxylic acids. C31 and C33 n-alkanes and C32 and C34 n-carboxylic acids can be attributed to grasses and herbs. Degradation of both compound classes in paleosols and sediments should be taken into consideration (e.g. Zech et al. 2013b), but the impact of degradation is not yet fully understood. We are now running compound-specific stable isotope analyses on all transect samples to evaluate the potential of the deuterium/hydrogen ratios in leaf waxes as proxy for the hydrological conditions. In addition, we aim at presenting first results of leaf wax biomarker analyses for a last-glacial loess-paleosol sequence from Spain. References Zech M., Krause T., Meszner M. & Faust D. 2013b: Incorrect when uncorrected: Reconstructing vegetation history using n-alkane biomarkers in loess-paleosol sequences: A case study from the Saxonian loess region, Germany. Quaternary International, 296, 108-116. Zech, R., Zech, M., Marković, S., Hambach, U. & Huang Y. 2013a: Humid glacials, arid interglacials? Critical thoughts on pedogenesis and paleoclimate based on multi-proxy analyses of the loess-paleosol sequence Crvenka, Northern Serbia. Palaeogeography, Palaeoclimatology, Palaeoecology, 387, 165-175.

  16. Effect of annealing temperature on optical properties of binary zinc tin oxide nano-composite prepared by sol-gel route using simple precursors: Structural and optical studies by DRS, FT-IR, XRD, FESEM investigations

    NASA Astrophysics Data System (ADS)

    Habibi, Mohammad Hossein; Mardani, Maryam

    2015-02-01

    Binary zinc tin oxide nano-composite was synthesized by a facile sol-gel method using simple precursors from the solutions consisting of zinc acetate, tin(IV) chloride and ethanol. Effect of annealing temperature on optical and structural properties was investigated using X-ray diffraction (XRD), diffuse reflectance spectra (DRS), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). XRD results revealed the existence of the ZnO and SnO2 phases. FESEM results showed that binary zinc tin oxide nano-composites ranges from 56 to 60 nm in diameter at 400 °C and 500 °C annealing temperatures respectively. The optical band gap was increased from 2.72 eV to 3.11 eV with the increasing of the annealing temperature. FTIR results confirmed the presence of zinc oxide and tin oxide and the broad absorption peaks at 3426 and 1602 cm-1 can be ascribed to the vibration of absorptive water, and the absorption peaks at 546, 1038 and 1410 cm-1 are due to the vibration of Zn-O or Sn-O groups in binary zinc tin oxide.

  17. Effect of annealing temperature on optical properties of binary zinc tin oxide nano-composite prepared by sol-gel route using simple precursors: structural and optical studies by DRS, FT-IR, XRD, FESEM investigations.

    PubMed

    Habibi, Mohammad Hossein; Mardani, Maryam

    2015-02-25

    Binary zinc tin oxide nano-composite was synthesized by a facile sol-gel method using simple precursors from the solutions consisting of zinc acetate, tin(IV) chloride and ethanol. Effect of annealing temperature on optical and structural properties was investigated using X-ray diffraction (XRD), diffuse reflectance spectra (DRS), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). XRD results revealed the existence of the ZnO and SnO2 phases. FESEM results showed that binary zinc tin oxide nano-composites ranges from 56 to 60 nm in diameter at 400°C and 500°C annealing temperatures respectively. The optical band gap was increased from 2.72 eV to 3.11 eV with the increasing of the annealing temperature. FTIR results confirmed the presence of zinc oxide and tin oxide and the broad absorption peaks at 3426 and 1602 cm(-1) can be ascribed to the vibration of absorptive water, and the absorption peaks at 546, 1038 and 1410 cm(-1) are due to the vibration of Zn-O or Sn-O groups in binary zinc tin oxide.

  18. Fischer-Tropsch wax characterization and upgrading: Final report

    SciTech Connect

    Shah, P.P.; Sturtevant, G.C.; Gregor, J.H.; Humbach, M.J.; Padrta, F.G.; Steigleder, K.Z.

    1988-06-06

    The characterization and upgrading of Fischer-Tropsch wax was studied. The focus of the program was to maximize the yield of marketable transportation fuels from the Fischer-Tropsch process. The wax was characterized using gel permeation chromatography (GPC), high resolution mass spectrometry (HRMS), infrared spectroscopy (IR), gas chromatography (GC), nuclear magnetic resonance (NMR) and various other physical analyses. Hydrocracking studies conducted in a pilot plant indicate that Fischer-Tropsch wax is an excellent feedstock. A high yield of excellent quality diesel fuel was produced with satisfactory catalyst performance at relatively mild operating conditions. Correlations for predicting key diesel fuel properties were developed and checked against actual laboratory blend data. The blending study was incorporated into an economic evaluation. Finally, it is possible to take advantage of the high quality of the Fischer-Tropsch derived distillate by blending a lower value light cycle oil (produced from a refinery FCC unit) representing a high aromatic and low cetane number. The blended stream meets diesel pool specifications (up to 60 wt % LCO addition). The value added to this blending stream further enhances the upgrading complex return. 22 refs., 39 figs., 48 tabs.

  19. Radiological properties of a wax-gypsum compensator material

    SciTech Connect

    Plessis, F.C.P. du; Willemse, C.A.

    2005-05-01

    In this paper the radiological properties of a compensator material consisting of wax and gypsum is presented. Effective attenuation coefficients (EACs) have been determined from transmission measurements with an ion chamber in a Perspex phantom. Measurements were made at 80 and 100 cm source-to-skin distance (SSD) for beam energies of 6, 8, and 15 MV, for field sizes ranging from narrow beam geometries up to 40x40 cm{sup 2}, and at measurement depths of maximum dose build-up, 5 and 10 cm. A parametrization equation could be constructed to predict the EAC values within 4% uncertainty as a function of field size and depth of measurement. The EAC dependence on off-axis position was also quantified at each beam energy and SSD. It was found that the compensator material reduced the required thickness for compensation by 26% at 8 MV when compared to pure paraffin wax for a 10x10 cm{sup 2} field. Relative surface ionization (RSI) measurements have been made to quantify the effect of scattered electrons from the wax-gypsum compensator. Results indicated that for 80 cm SSD the RSI would exceed 50% for fields larger than 15x15 cm{sup 2}. At 100 cm SSD the RSI values were below 50% for all field sizes used.

  20. Ultrasound assisted manufacturing of paraffin wax nanoemulsions: process optimization.

    PubMed

    Jadhav, A J; Holkar, C R; Karekar, S E; Pinjari, D V; Pandit, A B

    2015-03-01

    This work reports on the process optimization of ultrasound-assisted, paraffin wax in water nanoemulsions, stabilized by modified sodium dodecyl sulfate (SDS). This work focuses on the optimization of major emulsification process variables including sonication time, applied power and surfactant concentration. The effects of these variables were investigated on the basis of mean droplet diameter and stability of the prepared emulsion. It was found that the stable emulsion with droplet diameters about 160.9 nm could be formed with the surfactant concentration of 10 mg/ml and treated at 40% of applied power (power density: 0.61 W/ml) for 15 min. Scanning electron microscopy (SEM) was used to study the morphology of the emulsion droplets. The droplets were solid at room temperature, showing bright spots under polarized light and a spherical shape under SEM. The electrophoretic properties of emulsion droplets showed a negative zeta potential due to the adsorption of head sulfate groups of the SDS surfactant. For the sake of comparison, paraffin wax emulsion was prepared via emulsion inversion point method and was checked its intrinsic stability. Visually, it was found that the emulsion get separated/creamed within 30 min. while the emulsion prepared via ultrasonically is stable for more than 3 months. From this study, it was found that the ultrasound-assisted emulsification process could be successfully used for the preparation of stable paraffin wax nanoemulsions.

  1. A hydrodynamically-induced morphology transition in wax

    NASA Astrophysics Data System (ADS)

    King, , Jr.; Hutter, Jeffrey

    2001-03-01

    The growth of lath-shaped single crystals of wax from bulk solution is well studied and exhibits prototypic step growth. The axes of the linear wax molecules are perpendicular to the growth faces, leading to large, flat plates of wax conformal with the substrate surface. Such coatings are often a problem in pipes that transport petroleum. However, a second, unusual tree-like morphology, composed of twisted crystalline ribbons with a well-defined average distance between branches, can also be induced to grow on a cold substrate. We have studied these growth forms in a system consisting of a cooled silicon surface, with a surface energy controlled by monolayer coatings, immersed in an n-alkane solution. We find that parameters such as the surface energy and supersaturation have little effect on selecting the mode of growth. However, increasing the flow velocity of solution across the surface selects the tree morphology and strongly affects its form. Here, we suggest that the selection mechanism is by preferential delamination of plates, thus selecting the thermodynamically less stable tree form, and discuss the growth mechanism of the tree morphology itself.

  2. Ultrasound assisted manufacturing of paraffin wax nanoemulsions: process optimization.

    PubMed

    Jadhav, A J; Holkar, C R; Karekar, S E; Pinjari, D V; Pandit, A B

    2015-03-01

    This work reports on the process optimization of ultrasound-assisted, paraffin wax in water nanoemulsions, stabilized by modified sodium dodecyl sulfate (SDS). This work focuses on the optimization of major emulsification process variables including sonication time, applied power and surfactant concentration. The effects of these variables were investigated on the basis of mean droplet diameter and stability of the prepared emulsion. It was found that the stable emulsion with droplet diameters about 160.9 nm could be formed with the surfactant concentration of 10 mg/ml and treated at 40% of applied power (power density: 0.61 W/ml) for 15 min. Scanning electron microscopy (SEM) was used to study the morphology of the emulsion droplets. The droplets were solid at room temperature, showing bright spots under polarized light and a spherical shape under SEM. The electrophoretic properties of emulsion droplets showed a negative zeta potential due to the adsorption of head sulfate groups of the SDS surfactant. For the sake of comparison, paraffin wax emulsion was prepared via emulsion inversion point method and was checked its intrinsic stability. Visually, it was found that the emulsion get separated/creamed within 30 min. while the emulsion prepared via ultrasonically is stable for more than 3 months. From this study, it was found that the ultrasound-assisted emulsification process could be successfully used for the preparation of stable paraffin wax nanoemulsions. PMID:25465097

  3. Transient acceleration in f(T) gravity

    NASA Astrophysics Data System (ADS)

    Qi, Jing-Zhao; Yang, Rong-Jia; Zhang, Ming-Jian; Liu, Wen-Biao

    2016-02-01

    Recently an f(T) gravity based on the modification of teleparallel gravity was proposed to explain the accelerated expansion of the universe. We use observational data from type Ia supernovae, baryon acoustic oscillations, and cosmic microwave background to constrain this f(T) theory and reconstruct the effective equation of state and the deceleration parameter. We obtain the best-fit values of parameters and find an interesting result that the constrained f(T) theory allows for the accelerated Hubble expansion to be a transient effect.

  4. Phenotypic Expression in Wheat Revealed Using FT-IR Microspectroscopy

    SciTech Connect

    Brewer, L.; Wetzel, D

    2009-01-01

    Wheat selected for cultivation through the centuries has a glume that is 'soft' instead of 'tough' as naturally occurring. In production, this is desirable because it enables mechanical threshing with efficient separation of kernel from the head of each stalk without damaging the kernel. FT-IR microspectroscopy provides chemically based, objective assessment of genetic expression by measuring the extent of genetic expression. In the Microbeam Molecular Spectroscopy Laboratory, Manhattan, KS, an imaging FT-IR microspectrometer with a detector array focused on the image plane was used to obtain spectral data from dissected glume specimens of nine tough and eleven soft wheat cultivars in a rectangular mapping pattern. With cellulose as the substrate, the extent of lignification is measurable from the ratio of the lignin (1508 cm{sup -1}) baseline adjusted band area to the representative cellulosic (1370 cm{sup -1}) band area. A distinction between soft and tough glumes is obtained in numerical terms. Using a band ratio minimizes variation due to thickness differences. While analyzing mapped sections of glume, care is taken to avoid tabulation of spectral data from vascular bundles. Inclusion of these data would to avoid tabulation of spectral data from vascular bundles. Inclusion of these data would bias the analysis toward the composition of highly lignified vascular bundles. Spatially resolved focal plane array FT-IR microspectroscopy reveals the extent of glume lignification that is coincident with the toughness trait. This enables breeders to rank the degree of lignin expression and discriminate between soft and tough breeding results.

  5. Abiotic condensation synthesis of glyceride lipids and wax esters under simulated hydrothermal conditions.

    PubMed

    Rushdi, Ahmed I; Simoneit, Bernd R T

    2006-04-01

    Precursor compounds for abiotic proto cellular membranes are necessary for the origin of life. Amphipathic compounds such as fatty acids and acyl glycerols are important candidates for micelle/bilayer/vesicle formation. Two sets of experiments were conducted to study dehydration reactions of model lipid precursors in aqueous media to form acyl polyols and wax esters, and to evaluate the stability and reactions of the products at elevated temperatures. In the first set, mixtures of n-nonadecanoic acid and ethylene glycol in water, with and without oxalic acid, were heated at discrete temperatures from 150 ( composite function)C to 300 ( composite function)C for 72 h. The products were typically alkyl alkanoates, ethylene glycolyl alkanoates, ethylene glycolyl bis-alkanoates and alkanols. The condensation products had maximum yields between 150 ( composite function)C and 250 ( composite function)C, and were detectable and thus stable under hydrothermal conditions to temperatures < 300 ( composite function)C. In the second set of experiments, mixtures of n-heptanoic acid and glycerol were heated using the same experimental conditions, with and without oxalic acid, between 100 ( composite function)C and 250 ( composite function)C. The main condensation products were two isomers each of monoacylglycerols and diacylglycerols at all temperatures, as well as minor amounts of the fatty acid anhydride and methyl ester. The yield of glyceryl monoheptanoates generally increased with increasing temperature and glyceryl diheptanoates decreased noticeably with increasing temperature. The results indicate that condensation reactions and abiotic synthesis of organic lipid compounds under hydrothermal conditions occur easily, provided precursor concentrations are sufficiently high. PMID:16642268

  6. Candle and candle wax containing metathesis and metathesis-like products

    DOEpatents

    Murphy, Timothy A; Tupy, Michael J; Abraham, Timothy W; Shafer, Andy

    2014-12-16

    A wax comprises a metathesis product and/or a product that resembles, at least in part, a product which may be formed from a metathesis reaction. The wax may be used to form articles for example, candles (container candles, votive candles, and/or a pillar candles), crayons, fire logs or tarts. The wax commonly includes other components in addition to the metathesis product.

  7. Candle and candle wax containing metathesis and metathesis-like products

    SciTech Connect

    Murphy, Timothy A; Tupy, Michael J; Abraham, Timothy W; Shafer, Andy

    2014-04-01

    A wax comprises a metathesis product and/or a product that resembles, at least in part, a product which may be formed from a metathesis reaction. The wax may be used to form articles, for example, candles (container candles, votive candles, and/or a pillar candles), crayons, fire logs, or tarts. The wax commonly includes other components in addition to the metathesis product.

  8. Partitioning of Water Discharge by Distributary Channels in the Prograding, Wax Lake Delta, Coastal Louisiana, USA

    NASA Astrophysics Data System (ADS)

    Buttles, J.; Mohrig, D.; Nittrouer, J.; McElroy, B.; Baitis, E.; Allison, M.; Paola, C.; Parker, G.; Kim, W.

    2007-12-01

    How water and sediment is routed through distributary networks on river deltas is incompletely known and a topic of much active research. We have undertaken a study to determine the controls on partitioning of water and sediment discharge in distributary channels of the Wax Lake Delta and to connect these transport processes to the land building associated with the growth of islands that separate distributary channels from each other. Here we present first results from the field project that defines how water from the upstream primary channel is partitioned between the first set of five distributary channels. Measurements of water discharge and channel bathymetry were collected using a 22-ft research vessel equipped with an acoustic Doppler velocity profiler, a swath bathymetry profiler and dual differential GPS antennas. Wax Lake Delta is situated at the downstream end of Wax Lake Outlet, a man-made channel that diverts water and sediment from the lower Atchafalaya River, roughly 20 km upstream from Morgan City, LA. The subaerial delta has been building out into Atchafalaya Bay since roughly 1973 with a delta-front advance rate of about 0.27 km/yr. Associated with this growth has been development of a distributary network of channels that continues to evolve as the delta progrades seaward. Measurements collected in May, 2007 define properties of the upstream channel and the first set of five distributary channels. Characteristic width, depth and water discharge for the upstream channel are 420 m, 21.2 m, and 2900 m3/s. Characteristic values for width, depth and water discharge for the five distributary channels are 1) 270 m, 6.7 m, and 310 m3/s, 2) 300 m, 6.5 m, and 350 m3/s, 3) 650 m, 6.8 m, and 820 m3/s, 4) 395 m, 6.5 m, and 560 m3/s, and 5) 440 m, 6.0 m, and 440 m3/s. These data highlight a number of interesting points regarding the initial set of bifurcations. First, the transition from one to five channels is associated with a two-thirds reduction in

  9. Intracuticular wax fixes and restricts strain in leaf and fruit cuticles.

    PubMed

    Khanal, Bishnu Prasad; Grimm, Eckhard; Finger, Sebastian; Blume, Alfred; Knoche, Moritz

    2013-10-01

    This paper investigates the effects of cuticular wax on the release of strain and on the tensile properties of enzymatically isolated cuticular membranes (CMs) taken from leaves of agave (Agave americana), bush lily (Clivia miniata), holly (Ilex aquifolium), and ivy (Hedera helix) and from fruit of apple (Malus × domestica), pear (Pyrus communis), and tomato (Lycopersicon esculentum). Biaxial strain release was quantified as the decrease in CM disc area following wax extraction. Stiffness, maximum strain and maximum force were determined in uniaxial tensile tests using strips of CM and dewaxed CMs (DCMs). Biaxial strain release, stiffness, and maximum strain, but not maximum force, were linearly related to the amount of wax extracted. Apple CM has the most wax and here the effect of wax extraction was substantially accounted for by the embedded cuticular wax. Heating apple CM to 80°C melted some wax constituents and produced an effect similar to, but smaller than, that resulting from wax extraction. Our results indicate that wax 'fixes' strain, effectively converting reversible elastic into irreversible plastic strain. A consequence of 'fixation' is increased cuticular stiffness. PMID:23750808

  10. Chemical Signals from Avocado Surface Wax Trigger Germination and Appressorium Formation in Colletotrichum gloeosporioides.

    PubMed Central

    Podila, G. K.; Rogers, L. M.; Kolattukudy, P. E.

    1993-01-01

    The surface wax of the host, avocado (Persea americana) fruit, induced germination and appressorium formation in the spores of Colletotrichum gloeosporioides. Waxes from nonhost plants did not induce appressorium formation in this fungus, and avocado wax did not induce appressorium formation in most Colletotrichum species that infect other hosts. Bioassays of the thin-layer chromatographic fractions of the avocado wax showed that the fatty alcohol fraction was the main appressorium-inducing component. Testing of authentic n-C8 to n-C32 fatty alcohols revealed that C24 and longer-chain alcohols induced appressorium formation. Gas-liquid chromatography/mass spectrometry analysis of free fatty alcohols revealed that avocado wax contains a high content of very long chains. Waxes from nonhost plants containing an even higher content of the very long-chain alcohols did not induce appressorium formation. Waxes from nonhost plants strongly inhibited appressorium induction by avocado wax. Thus, a favorable balance between appressorium-inducing very long-chain fatty alcohols and the absence of inhibitors allows the fungus to use the host surface wax to trigger germination and differentiation of infection structures in the pathogen. PMID:12231933

  11. Critical Involvement of Environmental Carbon Dioxide Fixation to Drive Wax Ester Fermentation in Euglena

    PubMed Central

    Nishio, Kazuki; Nakazawa, Masami; Nakamoto, Masatoshi; Okazawa, Atsushi; Kanaya, Shigehiko; Arita, Masanori

    2016-01-01

    Accumulation profiles of wax esters in Euglena gracilis Z were studied under several environmental conditions. The highest amount of total wax esters accumulated under hypoxia in the dark, and C28 (myristyl-myristate, C14:0-C14:0) was prevalent among all conditions investigated. The wax ester production was almost completely suppressed under anoxia in the light, and supplying exogenous inorganic carbon sources restored wax ester fermentation, indicating the need for external carbon sources for the wax ester fermentation. 13C-labeling experiments revealed specific isotopic enrichment in the odd-numbered fatty acids derived from wax esters, indicating that the exogenously-supplied CO2 was incorporated into wax esters via the propionyl-CoA pathway through the reverse tricarboxylic acid (TCA) cycle. The addition of 3-mercaptopicolinic acid, a phosphoenolpyruvate carboxykinase (PEPCK) inhibitor, significantly affected the incorporation of 13C into citrate and malate as the biosynthetic intermediates of the odd-numbered fatty acids, suggesting the involvement of PEPCK reaction to drive wax ester fermentation. Additionally, the 13C-enrichment pattern of succinate suggested that the CO2 assimilation might proceed through alternative pathways in addition to the PEPCK reaction. The current results indicate that the mechanisms of anoxic CO2 assimilation are an important target to reinforce wax ester fermentation in Euglena. PMID:27669566

  12. Separating wax from hydrocarbon mixture boiling in the lubricating oil range

    SciTech Connect

    Ryan, D.G.; Cerkanowicz, A.E.; Chimenti, R.J.L.; Mintz, D.J.

    1986-12-09

    A method is described of pretreating a hydrocarbon oil mixture bailing in the lubricating oil range and containing dissolved wax, comprising the steps of reducing the solubility for the wax so as to cause dissolved wax in the oil to form a dispersion of wax particles in the oil mixture and introducing free excess charge which is net unipolar into the oil mixture, whereby wax particle agglomeration and particle size growth occurs. A method is also described wherein a first oil solvent liquid is added to the waxy oil mixture to form an admixture, the admixture is cooled to the cloud point of the admixture in the absence of any introduced free excess charge. Then a second oil solvent liquid is added to the admixture. The second oil solvent liquid a lower solubility for wax than for the admixture, so as to cause the wax to precipitate as wax particles. The free excess charge is introduced into the admixture of waxy oil mixture and first and second oil solvents, to bring about agglomeration and growth of the precipitated wax particles.

  13. Heavy wax distillate as a raw material for the production of solid hydrocarbons

    SciTech Connect

    Gundyrev, R.A.; Fokina, T.V.; Garun, Y.E.; Kazakova, L.P.; Sochevko, T.I.

    1984-07-01

    This article discusses the feasibility of recovering solid hydrocarbons from a heavy wax distillate in order to expand the raw material base for the production of high-melting waxes. The examined distillate has a melting point of 45/sup 0/C, a wax content of 34% by weight, a viscosity (at 100/sup 0/C) of 8.2 mm/sup 2//sec, a molecular weight of 345, a content of paraffinic and naphthenic hydrocarbons of 59.1% by weight, contents of aromatic hydrocarbons (light, medium and heavy) of 8.9%, 5.1%, and 20.4% by weight, respectively, and a content of hydrocarbons forming and not forming urea adducts of 21.8% and 78.2%, respectively. The heavy wax distillate was filtered in a Bogdanov laboratory unit containing a filter press consisting of a crystallizer and a slack wax chamber. The filtration residue from the crystallizer beaker and the slack wax cake from the wax chamber are collected in a preweighed container. It is concluded that the heavy wax distillate can be successfully dewaxed for wax production if it is modified by dilution with a filtrate and the incorporation of a structure modifier.

  14. Process for producing high quality, high molecular weight microcrystalline wax derived from undewaxed bright stock

    SciTech Connect

    Miller, S.J.

    1986-08-26

    A process is described for preparing high molecular weight microcrystalline wax from a hydrocracked, undewaxed bright stock, comprising: (a) contacting the bright stock with hydrogen in the presence of a catalyst having hydrodenitrification activity under conditions effective to reduce the nitrogen content of the stock to produce a substantially nitrogen-free product; (b) contacting the substantially nitrogen-free product with hydrogen in the presence of a catalyst having hydrogenation activity under mild conditions to produce a wax-containing oil; and (c) solvent dewaxing the wax-containing oil to produce high molecular weight microcrystalline wax.

  15. Mutants in Arabidopsis thaliana Altered in Epicuticular Wax and Leaf Morphology.

    PubMed Central

    Jenks, M. A.; Rashotte, A. M.; Tuttle, H. A.; Feldmann, K. A.

    1996-01-01

    We report eight new mutants in Arabidopsis thaliana possessing altered leaf morphology and epicuticular wax. These were isolated from a T-DNA-mutagenized population using a visual screen for altered leaf reflectance, i.e. increased glaucousness or glossiness. The mutants were placed into three distinct classes based on alterations in overall plant morphology: knobhead (knb), bicentifolia (bcf), and wax. The four knb mutants formed callus-like growths in the axillary region of the rosette leaves and apical meristem, the two bcf mutants produced hundreds of narrow leaves, and the two wax mutants had leaves and stems that were more glossy than wild type and organs that fused during early development. Leaves of knb and bcf were more glaucous and abnormally shaped than wild type. Epicuticular wax crystals over knb and bcf leaf surfaces (where none were present on wild type) likely contributed to their more glaucous appearance. In contrast, the glossy appearance of the wax mutants was associated with a reduced epicuticular wax load on both leaves and stems. One representative from each phenotypic class was selected for detailed analyses of epicuticular wax chemistry. All three lines, knb1, bcf1, and wax1, had dramatic alterations in the total amounts and relative proportions of their leaf epicuticular wax constituents. PMID:12226189

  16. Lost-Wax Casting in Ancient China: New Discussion on Old Debates

    NASA Astrophysics Data System (ADS)

    Zhou, Weirong; Huang, Wei

    2015-07-01

    The possible use of lost-wax casting in China has long been a matter of controversy. Based on the study of pertinent ancient texts concerning the technical origins of lost-wax casting in China, direct examination of questioned ancient Chinese bronzes as well as definite lost-wax castings from both overseas and China, and modern production of objects using piece-mold casting, the authors point out their own conceptual ideas about ancient lost-wax casting as follows. First, the lost-wax casting technique does not have its earliest origins in ancient China but rather from the Sumerians in Mesopotamia, where it was predominantly used to cast small human and animal figures (statuettes). Next, some essential characteristics of the lost-wax casting technique can be identified from the point of view of a distortable soft starting model. The locally deformed shape of lost-wax castings is found to be variable. Finally, it is improper to consider the ease of extraction from the mold as the criterion for distinguishing lost-wax casting from piece-mold casting. It is therefore incorrect to conclude that the three-dimensional openwork decorations present on Chinese bronzes from the Spring and Autumn Period, and the Warring States Period, are fabricated using lost-wax castings.

  17. Shape-tunable wax microparticle synthesis via microfluidics and droplet impact.

    PubMed

    Lee, Doojin; Beesabathuni, Shilpa N; Shen, Amy Q

    2015-11-01

    Spherical and non-spherical wax microparticles are generated by employing a facile two-step droplet microfluidic process which consists of the formation of molten wax microdroplets in a flow-focusing microchannel and their subsequent off-chip crystallization and deformation via microdroplet impingement on an immiscible liquid interface. Key parameters on the formation of molten wax microdroplets in a microfluidic channel are the viscosity of the molten wax and the interfacial tension between the dispersed and continuous fluids. A cursory phase diagram of wax morphology transition is depicted depending on the Capillary number and the Stefan number during the impact process. A combination of numerical simulation and analytical modeling is carried out to understand the physics underlying the deformation and crystallization process of the molten wax. The deformation of wax microdroplets is dominated by the viscous and thermal effects rather than the gravitational and buoyancy effects. Non-isothermal crystallization kinetics of the wax illustrates the time dependent thermal effects on the droplet deformation and crystallization. The work presented here will benefit those interested in the design and production criteria of soft non-spherical particles (i.e., alginate gels, wax, and polymer particles) with the aid of time and temperature mediated solidification and off-chip crosslinking.

  18. Shape-tunable wax microparticle synthesis via microfluidics and droplet impact.

    PubMed

    Lee, Doojin; Beesabathuni, Shilpa N; Shen, Amy Q

    2015-11-01

    Spherical and non-spherical wax microparticles are generated by employing a facile two-step droplet microfluidic process which consists of the formation of molten wax microdroplets in a flow-focusing microchannel and their subsequent off-chip crystallization and deformation via microdroplet impingement on an immiscible liquid interface. Key parameters on the formation of molten wax microdroplets in a microfluidic channel are the viscosity of the molten wax and the interfacial tension between the dispersed and continuous fluids. A cursory phase diagram of wax morphology transition is depicted depending on the Capillary number and the Stefan number during the impact process. A combination of numerical simulation and analytical modeling is carried out to understand the physics underlying the deformation and crystallization process of the molten wax. The deformation of wax microdroplets is dominated by the viscous and thermal effects rather than the gravitational and buoyancy effects. Non-isothermal crystallization kinetics of the wax illustrates the time dependent thermal effects on the droplet deformation and crystallization. The work presented here will benefit those interested in the design and production criteria of soft non-spherical particles (i.e., alginate gels, wax, and polymer particles) with the aid of time and temperature mediated solidification and off-chip crosslinking. PMID:26697124

  19. Intracuticular wax fixes and restricts strain in leaf and fruit cuticles.

    PubMed

    Khanal, Bishnu Prasad; Grimm, Eckhard; Finger, Sebastian; Blume, Alfred; Knoche, Moritz

    2013-10-01

    This paper investigates the effects of cuticular wax on the release of strain and on the tensile properties of enzymatically isolated cuticular membranes (CMs) taken from leaves of agave (Agave americana), bush lily (Clivia miniata), holly (Ilex aquifolium), and ivy (Hedera helix) and from fruit of apple (Malus × domestica), pear (Pyrus communis), and tomato (Lycopersicon esculentum). Biaxial strain release was quantified as the decrease in CM disc area following wax extraction. Stiffness, maximum strain and maximum force were determined in uniaxial tensile tests using strips of CM and dewaxed CMs (DCMs). Biaxial strain release, stiffness, and maximum strain, but not maximum force, were linearly related to the amount of wax extracted. Apple CM has the most wax and here the effect of wax extraction was substantially accounted for by the embedded cuticular wax. Heating apple CM to 80°C melted some wax constituents and produced an effect similar to, but smaller than, that resulting from wax extraction. Our results indicate that wax 'fixes' strain, effectively converting reversible elastic into irreversible plastic strain. A consequence of 'fixation' is increased cuticular stiffness.

  20. Method and apparatus for separating wax/water from hydrocarbon mixture boiling in the lubricating oil range

    SciTech Connect

    Mintz, D.J.; Gleason, A.M.

    1986-04-08

    A method is described of separating wax particles and/or water droplets from a hydrocarbon oil mixture boiling in the lubricating oil range, in which mixture the wax/water forms a dispersion. The free excess electric charge which is net unipolar is introduced into the wax/water-containing oil mixture and the charged wax/water-containing oil mixture and at least one collector surface are brought into contact with one another so that the wax/water collects, due to the electrophoretic migration of the wax/water caused by the introduced electric charge, and accumulates on the collector surface(s).

  1. Comparative study for separation of atmospheric humic-like substance (HULIS) by ENVI-18, HLB, XAD-8 and DEAE sorbents: elemental composition, FT-IR, 1H NMR and off-line thermochemolysis with tetramethylammonium hydroxide (TMAH).

    PubMed

    Fan, Xingjun; Song, Jianzhong; Peng, Ping'an

    2013-11-01

    Humic-like substances (HULIS) are significant constituents of aerosols, and the isolation and characterization of HULIS by solid-phase extraction methods are dependent on the sorbents used. In this study, we used the following five methods: ENVI-18, HLB-M, HLB-N, XAD-8 and DEAE, to isolate atmospheric HULIS at an urban site. Then we conducted a comparative investigation of the HULIS chemical characteristics by means of elemental analysis, Fourier transform infrared spectroscopy, (1)H nuclear magnetic resonance spectroscopy and off-line thermochemolysis with tetramethylammonium hydroxide. The results indicate that HULIS isolated using different methods show many similarities in chemical composition and structure. Some differences were however also observed between the five isolated HULIS: HULISHLB-M contains a relatively high content of OCH group, compared to HULISENVI-18 and HULISXAD-8; HULISXAD-8 contains a relatively high content of hydrophobic and aromatic components, compared to HULISENVI-18 and HULISHLB-M; HULISDEAE contains the highest content of aromatic functional groups, as inferred by (1)H NMR spectra, but a great amount of salts generally present in the HULISDEAE and thereby limited the choices for characterizing the materials (i.e., elemental analysis and TMAH thermochemolysis); HULISHLB-N has relatively high levels of H and N, a high N/C atomic ratio, and includes N-containing functional groups, which suggests that it has been altered by 2% ammonia introduced in the eluents. In summary, we found that ENVI-18, HLB-M, and XAD-8 are preferable methods for isolation and characterization of HULIS in atmospheric aerosols. These results also suggest that caution is required when applying DEAE and HLB-N isolating methods for characterizing atmospheric HULIS.

  2. Composites

    NASA Astrophysics Data System (ADS)

    Taylor, John G.

    The Composites market is arguably the most challenging and profitable market for phenolic resins aside from electronics. The variety of products and processes encountered creates the challenges, and the demand for high performance in critical operations brings value. Phenolic composite materials are rendered into a wide range of components to supply a diverse and fragmented commercial base that includes customers in aerospace (Space Shuttle), aircraft (interiors and brakes), mass transit (interiors), defense (blast protection), marine, mine ducting, off-shore (ducts and grating) and infrastructure (architectural) to name a few. For example, phenolic resin is a critical adhesive in the manufacture of honeycomb sandwich panels. Various solvent and water based resins are described along with resin characteristics and the role of metal ions for enhanced thermal stability of the resin used to coat the honeycomb. Featured new developments include pultrusion of phenolic grating, success in RTM/VARTM fabricated parts, new ballistic developments for military vehicles and high char yield carbon-carbon composites along with many others. Additionally, global regional market resin volumes and sales are presented and compared with other thermosetting resin systems.

  3. Method for the determination of natural ester-type gum bases used as food additives via direct analysis of their constituent wax esters using high-temperature GC/MS.

    PubMed

    Tada, Atsuko; Ishizuki, Kyoko; Yamazaki, Takeshi; Sugimoto, Naoki; Akiyama, Hiroshi

    2014-07-01

    Natural ester-type gum bases, which are used worldwide as food additives, mainly consist of wax esters composed of long-chain fatty acids and long-chain fatty alcohols. There are many varieties of ester-type gum bases, and thus a useful method for their discrimination is needed in order to establish official specifications and manage their quality control. Herein is reported a rapid and simple method for the analysis of different ester-type gum bases used as food additives by high-temperature gas chromatography/mass spectrometry (GC/MS). With this method, the constituent wax esters in ester-type gum bases can be detected without hydrolysis and derivatization. The method was applied to the determination of 10 types of gum bases, including beeswax, carnauba wax, lanolin, and jojoba wax, and it was demonstrated that the gum bases derived from identical origins have specific and characteristic total ion chromatogram (TIC) patterns and ester compositions. Food additive gum bases were thus distinguished from one another based on their TIC patterns and then more clearly discriminated using simultaneous monitoring of the fragment ions corresponding to the fatty acid moieties of the individual molecular species of the wax esters. This direct high-temperature GC/MS method was shown to be very useful for the rapid and simple discrimination of varieties of ester-type gum bases used as food additives. PMID:25473499

  4. Method for the determination of natural ester-type gum bases used as food additives via direct analysis of their constituent wax esters using high-temperature GC/MS

    PubMed Central

    Tada, Atsuko; Ishizuki, Kyoko; Yamazaki, Takeshi; Sugimoto, Naoki; Akiyama, Hiroshi

    2014-01-01

    Natural ester-type gum bases, which are used worldwide as food additives, mainly consist of wax esters composed of long-chain fatty acids and long-chain fatty alcohols. There are many varieties of ester-type gum bases, and thus a useful method for their discrimination is needed in order to establish official specifications and manage their quality control. Herein is reported a rapid and simple method for the analysis of different ester-type gum bases used as food additives by high-temperature gas chromatography/mass spectrometry (GC/MS). With this method, the constituent wax esters in ester-type gum bases can be detected without hydrolysis and derivatization. The method was applied to the determination of 10 types of gum bases, including beeswax, carnauba wax, lanolin, and jojoba wax, and it was demonstrated that the gum bases derived from identical origins have specific and characteristic total ion chromatogram (TIC) patterns and ester compositions. Food additive gum bases were thus distinguished from one another based on their TIC patterns and then more clearly discriminated using simultaneous monitoring of the fragment ions corresponding to the fatty acid moieties of the individual molecular species of the wax esters. This direct high-temperature GC/MS method was shown to be very useful for the rapid and simple discrimination of varieties of ester-type gum bases used as food additives. PMID:25473499

  5. Method for the determination of natural ester-type gum bases used as food additives via direct analysis of their constituent wax esters using high-temperature GC/MS.

    PubMed

    Tada, Atsuko; Ishizuki, Kyoko; Yamazaki, Takeshi; Sugimoto, Naoki; Akiyama, Hiroshi

    2014-07-01

    Natural ester-type gum bases, which are used worldwide as food additives, mainly consist of wax esters composed of long-chain fatty acids and long-chain fatty alcohols. There are many varieties of ester-type gum bases, and thus a useful method for their discrimination is needed in order to establish official specifications and manage their quality control. Herein is reported a rapid and simple method for the analysis of different ester-type gum bases used as food additives by high-temperature gas chromatography/mass spectrometry (GC/MS). With this method, the constituent wax esters in ester-type gum bases can be detected without hydrolysis and derivatization. The method was applied to the determination of 10 types of gum bases, including beeswax, carnauba wax, lanolin, and jojoba wax, and it was demonstrated that the gum bases derived from identical origins have specific and characteristic total ion chromatogram (TIC) patterns and ester compositions. Food additive gum bases were thus distinguished from one another based on their TIC patterns and then more clearly discriminated using simultaneous monitoring of the fragment ions corresponding to the fatty acid moieties of the individual molecular species of the wax esters. This direct high-temperature GC/MS method was shown to be very useful for the rapid and simple discrimination of varieties of ester-type gum bases used as food additives.

  6. Comparison of various extraction methods for policosanol from rice bran wax and establishment of chromatographic fingerprint of policosanol.

    PubMed

    Wang, Mei-Fei; Lian, Hong-Zhen; Mao, Li; Zhou, Jing-Ping; Gong, Hui-Juan; Qian, Bao-Yong; Fang, Yan; Li, Jie

    2007-07-11

    A capillary gas chromatographic (GC) method has been developed for the separation and determination of policosanol components extracted from rice bran wax. A Varian CP-sil 8 CB column was employed, and an oven temperature was programmed. Gas chromatography-mass spectrometry (GC-MS) was used to identify the composition of policosanol. Quantitative analysis was carried out by means of hydrogen flame ionization detector (FID) with dinonyl phthalate (DNP) as internal standard. The results indicated that the extract obtained by dry saponification has the highest contents of octacosanol and triacontanol among extracts by all used extraction methods including dry saponification, saponification in alcohol, saponification in water (neutralized and non-neutralized), and transesterification. Meanwhile, the GC-MS fingerprint of policosanol extracted by dry saponification has been established. Euclidean distance similarity calculation showed remarkable consistency of compositions and contents among 12 batches of policosanol from a rice bran wax variety. This protocol provided a rapid and feasible method for quality control of policosanol products.

  7. In Vivo Chemical and Structural Analysis of Plant Cuticular Waxes Using Stimulated Raman Scattering Microscopy1[OPEN

    PubMed Central

    Mansfield, Jessica C.; Perfect, Sarah; Seymour, Mark; Smirnoff, Nicholas; Love, John; Moger, Julian

    2015-01-01

    The cuticle is a ubiquitous, predominantly waxy layer on the aerial parts of higher plants that fulfils a number of essential physiological roles, including regulating evapotranspiration, light reflection, and heat tolerance, control of development, and providing an essential barrier between the organism and environmental agents such as chemicals or some pathogens. The structure and composition of the cuticle are closely associated but are typically investigated separately using a combination of structural imaging and biochemical analysis of extracted waxes. Recently, techniques that combine stain-free imaging and biochemical analysis, including Fourier transform infrared spectroscopy microscopy and coherent anti-Stokes Raman spectroscopy microscopy, have been used to investigate the cuticle, but the detection sensitivity is severely limited by the background signals from plant pigments. We present a new method for label-free, in vivo structural and biochemical analysis of plant cuticles based on stimulated Raman scattering (SRS) microscopy. As a proof of principle, we used SRS microscopy to analyze the cuticles from a variety of plants at different times in development. We demonstrate that the SRS virtually eliminates the background interference compared with coherent anti-Stokes Raman spectroscopy imaging and results in label-free, chemically specific confocal images of cuticle architecture with simultaneous characterization of cuticle composition. This innovative use of the SRS spectroscopy may find applications in agrochemical research and development or in studies of wax deposition during leaf development and, as such, represents an important step in the study of higher plant cuticles. PMID:25783412

  8. Developments in FT-ICR MS instrumentation, ionization techniques, and data interpretation methods for petroleomics.

    PubMed

    Cho, Yunju; Ahmed, Arif; Islam, Annana; Kim, Sunghwan

    2015-01-01

    Because of the increasing importance of heavy and unconventional crude oil as an energy source, there is a growing need for petroleomics: the pursuit of more complete and detailed knowledge of the chemical compositions of crude oil. Crude oil has an extremely complex nature; hence, techniques with ultra-high resolving capabilities, such as Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), are necessary. FT-ICR MS has been successfully applied to the study of heavy and unconventional crude oils such as bitumen and shale oil. However, the analysis of crude oil with FT-ICR MS is not trivial, and it has pushed analysis to the limits of instrumental and methodological capabilities. For example, high-resolution mass spectra of crude oils may contain over 100,000 peaks that require interpretation. To visualize large data sets more effectively, data processing methods such as Kendrick mass defect analysis and statistical analyses have been developed. The successful application of FT-ICR MS to the study of crude oil has been critically dependent on key developments in FT-ICR MS instrumentation and data processing methods. This review offers an introduction to the basic principles, FT-ICR MS instrumentation development, ionization techniques, and data interpretation methods for petroleomics and is intended for readers having no prior experience in this field of study.

  9. Preliminary evaluation of an aqueous wax emulsion for controlled-release coating.

    PubMed

    Walia, P S; Stout, P J; Turton, R

    1998-02-01

    The purpose of this work was to evaluate the use of an aqueous carnauba wax emulsion (Primafresh HS, Johnson Wax) in a spray-coating process. This involved assessing the effectiveness of the wax in sustaining the release of the drug, theophylline. Second, the process by which the drug was released from the wax-coated pellets was modeled. Finally, a method to determine the optimum blend of pellets with different wax thicknesses, in order to yield a zero-order release profile of the drug, was addressed. Nonpareil pellets were loaded with theophylline using a novel powder coating technique. These drug-loaded pellets were then coated with different levels of carnauba wax in a 6-in. diameter Plexiglas fluid bed with a 3.5-in. diameter Wurster partition. Drug release was measured using a spin-filter dissolution device. The study resulted in continuous carnauba wax coatings which showed sustained drug release profile characteristics typical of a barrier-type, diffusion-controlled system. The effect of varying wax thickness on the release profiles was investigated. It was observed that very high wax loadings would be required to achieve long sustained-release times. The diffusion model, developed to predict the release of the drug, showed good agreement with the experimental data. However, the data exhibited an initial lag-time for drug release which could not be predicted a priori based on the wax coating thickness. A method of mixing pellets with different wax thicknesses was proposed as a way to approximate zero-order release. PMID:9532605

  10. Paraffin wax emulsion for increased rainfastness of insecticidal bait to control Rhagoletis pomonella (Diptera: Tephritidae).

    PubMed

    Teixeira, Luís A F; Wise, John C; Gut, Larry J; Isaacs, Rufus

    2009-06-01

    In regions with a humid summer climate, the use of water-soluble bait to control apple maggot is often limited by rainfall. We studied increasing the rainfastness of GF-120 fruit fly bait by adding paraffin wax emulsion. First, we verified that adding 10% wax to a mixture containing 16.7% GF-120 did not reduce the mortality of female apple maggot compared with GF-120 without wax. In addition, we determined that fly mortality caused by GF-120 plus wax subjected to simulated rain was similar to that caused by GF-120 without wax not subjected to rain. Other assays showed that higher fly mortality resulted from increasing the proportion of wax from 10 to 15%, and lower mortality resulted from decreasing GF-120 from 16.7 to 10 or 5%. The availability of spinosad on or near droplets of a mixture consisting of 5, 10, or 15% GF-120 and 15% wax was determined before and after the droplets were subjected to three 15-min periods of simulated rain. We found an initial steep decline in dislodgeable spinosad and smaller decreases after subsequent periods of rain. In a small-plot field trial, fruit infestation by apple maggot in plots treated with a mixture consisting of 16.7% GF-120 and 19.2% wax was less than in plots treated with 16.7% GF-120 without wax but not less than in control plots. Overall, we found that adding paraffin wax emulsion to GF-120 increased rainfastness in laboratory bioassays, and specifically that it retained the active ingredient spinosad. However, our field data suggest that optimal rainfastness requires the development of mixtures with > 19.2% wax, which may preclude application using standard spray equipment.

  11. Preliminary evaluation of an aqueous wax emulsion for controlled-release coating.

    PubMed

    Walia, P S; Stout, P J; Turton, R

    1998-02-01

    The purpose of this work was to evaluate the use of an aqueous carnauba wax emulsion (Primafresh HS, Johnson Wax) in a spray-coating process. This involved assessing the effectiveness of the wax in sustaining the release of the drug, theophylline. Second, the process by which the drug was released from the wax-coated pellets was modeled. Finally, a method to determine the optimum blend of pellets with different wax thicknesses, in order to yield a zero-order release profile of the drug, was addressed. Nonpareil pellets were loaded with theophylline using a novel powder coating technique. These drug-loaded pellets were then coated with different levels of carnauba wax in a 6-in. diameter Plexiglas fluid bed with a 3.5-in. diameter Wurster partition. Drug release was measured using a spin-filter dissolution device. The study resulted in continuous carnauba wax coatings which showed sustained drug release profile characteristics typical of a barrier-type, diffusion-controlled system. The effect of varying wax thickness on the release profiles was investigated. It was observed that very high wax loadings would be required to achieve long sustained-release times. The diffusion model, developed to predict the release of the drug, showed good agreement with the experimental data. However, the data exhibited an initial lag-time for drug release which could not be predicted a priori based on the wax coating thickness. A method of mixing pellets with different wax thicknesses was proposed as a way to approximate zero-order release.

  12. Synthesis of oleyl oleate wax esters in Arabidopsis thaliana and Camelina sativa seed oil.

    PubMed

    Iven, Tim; Hornung, Ellen; Heilmann, Mareike; Feussner, Ivo

    2016-01-01

    Seed oil composed of wax esters with long-chain monoenoic acyl moieties represents a high-value commodity for industry. Such plant-derived sperm oil-like liquid wax esters are biodegradable and can have excellent properties for lubrication. In addition, wax ester oil may represent a superior substrate for biodiesel production. In this study, we demonstrate that the low-input oil seed crop Camelina sativa can serve as a biotechnological platform for environmentally benign wax ester production. Two biosynthetic steps catalysed by a fatty alcohol-forming acyl-CoA reductase (FAR) and a wax ester synthase (WS) are sufficient to achieve wax ester accumulation from acyl-CoA substrates. To produce plant-derived sperm oil-like liquid wax esters, the WS from Mus musculus (MmWS) or Simmondsia chinensis (ScWS) were expressed in combination with the FAR from Mus musculus (MmFAR1) or Marinobacter aquaeolei (MaFAR) in seeds of Arabidopsis thaliana and Camelina sativa. The three analysed enzyme combinations Oleo3:mCherry:MmFAR1∆c/Oleo3:EYFP:MmWS, Oleo3:mCherry:MmFAR1∆c/ScWS and MaFAR/ScWS showed differences in the wax ester molecular species profiles and overall biosynthetic performance. By expressing MaFAR/ScWS in Arabidopsis or Camelina up to 59% or 21% of the seed oil TAGs were replaced by wax esters, respectively. This combination also yielded wax ester molecular species with highest content of monounsaturated acyl moieties. Expression of the enzyme combinations in the Arabidopsis fae1 fad2 mutant background high in oleic acid resulted in wax ester accumulation enriched in oleyl oleate (18:1/18:1 > 60%), suggesting that similar values may be obtained with a Camelina high oleic acid line.

  13. The benefits of Fischer-Tropsch waxes in synthetic petroleum jelly.

    PubMed

    Bekker, M; Louw, N R; Jansen Van Rensburg, V J; Potgieter, J

    2013-02-01

    This article is an introduction and general discussion regarding the use of Fisher-Tropsch wax in petroleum jelly applications. Traditionally, petroleum jelly is prepared from a blend of microwax, paraffin wax and mineral oil that are all derived from crude oil. Sasol Wax has successfully prepared a petroleum jelly based on predominantly to fully synthetic Fisher-Tropsch wax. Sasol Wax was awarded a patent P53898ZP00-29 November 11 for a predominantly to fully synthetic petroleum jelly based on Fisher-Tropsch wax blends. The benefits of Fisher-Tropsch wax discussed in this article include the absence of aromatic compounds and polycyclic aromatic compounds in Fisher-Tropsch wax as well as the sustainable production that is possible with Fisher-Tropsch wax, as opposed to paraffin wax that may be affected by the closure of group I Base Oil plants. This article will be the first in a series of articles from the same authors, and follow-up articles will include solid-state nuclear magnetic resonance and crystallization studies to determine the influence of predominantly synthetic waxes on petroleum jelly network structures compared with more traditional mineral oil-derived petroleum jellies, final product performance and stability of synthetic petroleum jelly used in, for example, personal care lotions or creams. The influence of oxygenated compounds and product safety and rheological properties (including primary skin feel upon application and secondary skin feel after application) of synthetic petroleum jellies compared with traditional mineral oil-derived petroleum jellies are discussed.

  14. Economics of comb wax salvage by the red dwarf honeybee, Apis florea.

    PubMed

    Pirk, Christian W W; Crous, Kendall L; Duangphakdee, Orawan; Radloff, Sarah E; Hepburn, Randall

    2011-04-01

    Colonies of Apis florea, which only abscond a short distance, usually return to salvage old nest wax; but, those colonies, and all other honeybee species which go considerably further, do not. Wax salvage would clearly be counter-productive unless the energy input/energy yield threshold was a profitable one. There are two possible trade-offs in this scenario, the trade-off between the energy expended to recover the wax (recovering hypothesis) as against that of replacing the wax by new secretion (replacing hypothesis). In order to compare the two hypotheses, the fuel costs involved in salvaging wax on one return trip, the average flower handling time, flight time and relative values for substituting the salvaged wax with nectar were calculated. Moreover, the energy value of the wax was determined. Net energy gains for salvaged wax were calculated. The energy value of the salvaged wax was 42.7 J/mg, thus too high to be the limiting factor since salvaging costs are only 642.76 mJ/mg (recovering hypothesis). The recovery costs (642.76 mJ/mg) only fall below the replacement costs for absconding distance below 115 m thus supporting the replacing hypothesis. This energetic trade-off between replacing and recycling plus the small absconding range of A. florea might explain why A. florea is probably the only honeybee species known to salvage wax and it parsimoniously explains the underlying reasons why A. florea only salvages wax from the old nest if the new nesting site is less than 100-200 m away-energetically, it pays off to recycle.

  15. Properties of Cookies Made with Natural Wax-Vegetable Oil Organogels.

    PubMed

    Hwang, Hong-Sik; Singh, Mukti; Lee, Suyong

    2016-05-01

    The aim of this study was to examine the feasibility of cookies in which the conventional margarine is replaced with an organogel of vegetable oil (VO) and natural wax. New cookies from VO organogels contain no trans fats and much less saturated fats than cookies made with a conventional margarine. To understand the effects of different kinds of waxes, organogels were prepared from 4 different waxes including sunflower wax (SW), rice bran wax (RBW), beeswax, and candelilla wax and properties of cookie dough and cookie were evaluated. To investigate the effects of different VOs on the properties of cookies, 3 VOs including olive oil, soybean oil and flaxseed oil representing oils rich in oleic acid (18:1), linoleic acid (18:2), and linolenic acid (18:3), respectively, were used. Both the wax and VO significantly affected properties of organogel such as firmness and melting behavior shown in differential scanning calorimetry. The highest firmness of organogel was observed with SW and flaxseed oil. Properties of dough such as hardness and melting behavior were also significantly affected by wax and VO while trends were somewhat different from those for organogels. SW and RBW provided greatest hardnesses to cookie dough. However, hardness, spread factor, and fracturability of cookie containing the wax-VO organogel were not significantly affected by different waxes and VOs. Several cookies made with wax-VO organogels showed similar properties to cookies made with a commercial margarine. Therefore, this study shows the high feasibility of utilization of the organogel technology in real foods such as cookies rich in unsaturated fats.

  16. The benefits of Fischer-Tropsch waxes in synthetic petroleum jelly.

    PubMed

    Bekker, M; Louw, N R; Jansen Van Rensburg, V J; Potgieter, J

    2013-02-01

    This article is an introduction and general discussion regarding the use of Fisher-Tropsch wax in petroleum jelly applications. Traditionally, petroleum jelly is prepared from a blend of microwax, paraffin wax and mineral oil that are all derived from crude oil. Sasol Wax has successfully prepared a petroleum jelly based on predominantly to fully synthetic Fisher-Tropsch wax. Sasol Wax was awarded a patent P53898ZP00-29 November 11 for a predominantly to fully synthetic petroleum jelly based on Fisher-Tropsch wax blends. The benefits of Fisher-Tropsch wax discussed in this article include the absence of aromatic compounds and polycyclic aromatic compounds in Fisher-Tropsch wax as well as the sustainable production that is possible with Fisher-Tropsch wax, as opposed to paraffin wax that may be affected by the closure of group I Base Oil plants. This article will be the first in a series of articles from the same authors, and follow-up articles will include solid-state nuclear magnetic resonance and crystallization studies to determine the influence of predominantly synthetic waxes on petroleum jelly network structures compared with more traditional mineral oil-derived petroleum jellies, final product performance and stability of synthetic petroleum jelly used in, for example, personal care lotions or creams. The influence of oxygenated compounds and product safety and rheological properties (including primary skin feel upon application and secondary skin feel after application) of synthetic petroleum jellies compared with traditional mineral oil-derived petroleum jellies are discussed. PMID:23050609

  17. Properties of Cookies Made with Natural Wax-Vegetable Oil Organogels.

    PubMed

    Hwang, Hong-Sik; Singh, Mukti; Lee, Suyong

    2016-05-01

    The aim of this study was to examine the feasibility of cookies in which the conventional margarine is replaced with an organogel of vegetable oil (VO) and natural wax. New cookies from VO organogels contain no trans fats and much less saturated fats than cookies made with a conventional margarine. To understand the effects of different kinds of waxes, organogels were prepared from 4 different waxes including sunflower wax (SW), rice bran wax (RBW), beeswax, and candelilla wax and properties of cookie dough and cookie were evaluated. To investigate the effects of different VOs on the properties of cookies, 3 VOs including olive oil, soybean oil and flaxseed oil representing oils rich in oleic acid (18:1), linoleic acid (18:2), and linolenic acid (18:3), respectively, were used. Both the wax and VO significantly affected properties of organogel such as firmness and melting behavior shown in differential scanning calorimetry. The highest firmness of organogel was observed with SW and flaxseed oil. Properties of dough such as hardness and melting behavior were also significantly affected by wax and VO while trends were somewhat different from those for organogels. SW and RBW provided greatest hardnesses to cookie dough. However, hardness, spread factor, and fracturability of cookie containing the wax-VO organogel were not significantly affected by different waxes and VOs. Several cookies made with wax-VO organogels showed similar properties to cookies made with a commercial margarine. Therefore, this study shows the high feasibility of utilization of the organogel technology in real foods such as cookies rich in unsaturated fats. PMID:27027545

  18. Offshore asphaltene and wax deposition: Problems/solutions

    SciTech Connect

    Leontaritis, K.J. |

    1996-05-01

    Many production facilities around the world suffer from either asphaltene or wax deposition. Such problems seriously threaten economic production from many offshore reservoirs due to the high cost of remedial measures. Offshore facilities are especially susceptible to such deposition for a number of reasons. This article presents ideas and methodologies on how to predict, diagnose, prevent, or mitigate problems caused by organic deposition in offshore production facilities. In one facility where these ideas were put to use, despite the debilitating magnitude of the problems, the field has been produced for more than 14 years with minimum environmental impact. Principal conclusions developed are discussed in this paper.

  19. Three Dimensional Morphodynamic and Vegetation Modeling of Wax Lake Delta

    NASA Astrophysics Data System (ADS)

    Khadka, A. K.; Meselhe, E. A.; Sadid, K. M.

    2013-12-01

    The Wax Lake Delta (WLD) is located at the downstream end of the Wax Lake outlet, approximately 13 miles upstream from Morgan City, Louisiana. In 1942 the United States Army Corps of Engineer (USACE) dredged Wax Lake Outlet channel from lower Atchafalaya River to reduce flood stages at Morgan City. The channel diverts 50% of Atchafalaya River water and sediment to WLD. Since 1942, the WLD has been building seaward due to the deposition of sediment at the channel mouth. Growth of this delta supports the concept of land building via river diversions. A process based morphodynamic model (Delft3D) with the ability to predict evolution of river-dominated deltas is used in this study to further our understanding of land-building and delta growth processes. Initial model bathymetry is prepared based on USACE hydrographic survey of 1998 along with LIDAR survey data for over bank areas. Two continuous gauges at Wax Lake outlet near Calumet and Atchafalaya Bay near Eugene Island are used to assign upstream inflow and outflow boundary conditions, respectively. The model is calibrated and validated for Hydrodynamics and Sediment transport through two sets of field observations for flooded and average conditions. Vertical velocity and suspended sediment profiles made in the channels of the WLD in 2000 and 2001 are used for the model calibration and validation. More comprehensive field observations are being gathered as part of an ongoing study funded by the National Science Foundation (FESD-Delta Dynamics Collaboratory). Data include mutli-beam bathymetric data, velocities, sediment, and nutrient concentrations in the channels as well as on top of the islands. The Delft3D morphodynamic model for WLD provides quantitative information regarding water and sediment distribution among the inter-connected channel bifurcations, the exchange of sediment and nutrients between the channels and islands. The model is being used to investigate the rate of land building and delta growth from

  20. WAXS fat subtraction model to estimate differential linear scattering coefficients of fatless breast tissue: Phantom materials evaluation

    SciTech Connect

    Tang, Robert Y.; Laamanen, Curtis McDonald, Nancy; LeClair, Robert J.

    2014-05-15

    Purpose: Develop a method to subtract fat tissue contributions to wide-angle x-ray scatter (WAXS) signals of breast biopsies in order to estimate the differential linear scattering coefficients μ{sub s} of fatless tissue. Cancerous and fibroglandular tissue can then be compared independent of fat content. In this work phantom materials with known compositions were used to test the efficacy of the WAXS subtraction model. Methods: Each sample 5 mm in diameter and 5 mm thick was interrogated by a 50 kV 2.7 mm diameter beam for 3 min. A 25 mm{sup 2} by 1 mm thick CdTe detector allowed measurements of a portion of the θ = 6° scattered field. A scatter technique provided means to estimate the incident spectrum N{sub 0}(E) needed in the calculations of μ{sub s}[x(E, θ)] where x is the momentum transfer argument. Values of μ{sup ¯}{sub s} for composite phantoms consisting of three plastic layers were estimated and compared to the values obtained via the sum μ{sup ¯}{sub s}{sup ∑}(x)=ν{sub 1}μ{sub s1}(x)+ν{sub 2}μ{sub s2}(x)+ν{sub 3}μ{sub s3}(x), where ν{sub i} is the fractional volume of the ith plastic component. Water, polystyrene, and a volume mixture of 0.6 water + 0.4 polystyrene labelled as fibphan were chosen to mimic cancer, fat, and fibroglandular tissue, respectively. A WAXS subtraction model was used to remove the polystyrene signal from tissue composite phantoms so that the μ{sub s} of water and fibphan could be estimated. Although the composite samples were layered, simulations were performed to test the models under nonlayered conditions. Results: The well known μ{sub s} signal of water was reproduced effectively between 0.5 < x < 1.6 nm{sup −1}. The μ{sup ¯}{sub s} obtained for the heterogeneous samples agreed with μ{sup ¯}{sub s}{sup ∑}. Polystyrene signals were subtracted successfully from composite phantoms. The simulations validated the usefulness of the WAXS models for nonlayered biopsies. Conclusions: The methodology to

  1. Detection of starch adulteration in onion powder by FT-NIR and FT-IR spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adulteration of onion powder with cornstarch was identified by Fourier transform near-infrared (FT-NIR) and Fourier transform infrared (FT-IR) spectroscopy. The reflectance spectra of 180 pure and adulterated samples (1–35 wt% starch) were collected and preprocessed to generate calibration and predi...

  2. Composites

    NASA Astrophysics Data System (ADS)

    Chmielewski, M.; Nosewicz, S.; Pietrzak, K.; Rojek, J.; Strojny-Nędza, A.; Mackiewicz, S.; Dutkiewicz, J.

    2014-11-01

    It is commonly known that the properties of sintered materials are strongly related to technological conditions of the densification process. This paper shows the sintering behavior of a NiAl-Al2O3 composite, and its individual components sintered separately. Each kind of material was processed via the powder metallurgy route (hot pressing). The progress of sintering at different stages of the process was tested. Changes in the microstructure were examined using scanning and transmission electron microscopy. Metal-ceramics interface was clean and no additional phases were detected. Correlation between the microstructure, density, and mechanical properties of the sintered materials was analyzed. The values of elastic constants of NiAl/Al2O3 were close to intermetallic ones due to the volume content of the NiAl phase particularly at low densities, where small alumina particles had no impact on the composite's stiffness. The influence of the external pressure of 30 MPa seemed crucial for obtaining satisfactory stiffness for three kinds of the studied materials which were characterized by a high dense microstructure with a low number of isolated spherical pores.

  3. A method to estimate the fractional fat volume within a ROI of a breast biopsy for WAXS applications: Animal tissue evaluation

    SciTech Connect

    Tang, Robert Y.; McDonald, Nancy Laamanen, Curtis; LeClair, Robert J.

    2014-11-01

    Purpose: To develop a method to estimate the mean fractional volume of fat (ν{sup ¯}{sub fat}) within a region of interest (ROI) of a tissue sample for wide-angle x-ray scatter (WAXS) applications. A scatter signal from the ROI was obtained and use of ν{sup ¯}{sub fat} in a WAXS fat subtraction model provided a way to estimate the differential linear scattering coefficient μ{sub s} of the remaining fatless tissue. Methods: The efficacy of the method was tested using animal tissue from a local butcher shop. Formalin fixed samples, 5 mm in diameter 4 mm thick, were prepared. The two main tissue types were fat and meat (fibrous). Pure as well as composite samples consisting of a mixture of the two tissue types were analyzed. For the latter samples, ν{sub fat} for the tissue columns of interest were extracted from corresponding pixels in CCD digital x-ray images using a calibration curve. The means ν{sup ¯}{sub fat} were then calculated for use in a WAXS fat subtraction model. For the WAXS measurements, the samples were interrogated with a 2.7 mm diameter 50 kV beam and the 6° scattered photons were detected with a CdTe detector subtending a solid angle of 7.75 × 10{sup −5} sr. Using the scatter spectrum, an estimate of the incident spectrum, and a scatter model, μ{sub s} was determined for the tissue in the ROI. For the composite samples, a WAXS fat subtraction model was used to estimate the μ{sub s} of the fibrous tissue in the ROI. This signal was compared to μ{sub s} of fibrous tissue obtained using a pure fibrous sample. Results: For chicken and beef composites, ν{sup ¯}{sub fat}=0.33±0.05 and 0.32 ± 0.05, respectively. The subtractions of these fat components from the WAXS composite signals provided estimates of μ{sub s} for chicken and beef fibrous tissue. The differences between the estimates and μ{sub s} of fibrous obtained with a pure sample were calculated as a function of the momentum transfer x. A t-test showed that the mean of the

  4. Production of wax esters in plant seed oils by oleosomal cotargeting of biosynthetic enzymes[S

    PubMed Central

    Heilmann, Mareike; Iven, Tim; Ahmann, Katharina; Hornung, Ellen; Stymne, Sten; Feussner, Ivo

    2012-01-01

    Wax esters are neutral lipids exhibiting desirable properties for lubrication. Natural sources have traditionally been whales. Additionally some plants produce wax esters in their seed oil. Currently there is no biological source available for long chain length monounsaturated wax esters that are most suited for industrial applications. This study aimed to identify enzymatic requirements enabling their production in oilseed plants. Wax esters are generated by the action of fatty acyl-CoA reductase (FAR), generating fatty alcohols and wax synthases (WS) that esterify fatty alcohols and acyl-CoAs to wax esters. Based on their substrate preference, a FAR and a WS from Mus musculus were selected for this study (MmFAR1 and MmWS). MmWS resides in the endoplasmic reticulum (ER), whereas MmFAR1 associates with peroxisomes. The elimination of a targeting signal and the fusion to an oil body protein yielded variants of MmFAR1 and MmWS that were cotargeted and enabled wax ester production when coexpressed in yeast or Arabidopsis. In the fae1 fad2 double mutant, rich in oleate, the cotargeted variants of MmFAR1 and MmWS enabled formation of wax esters containing >65% oleyl-oleate. The data suggest that cotargeting of unusual biosynthetic enzymes can result in functional interplay of heterologous partners in transgenic plants. PMID:22878160

  5. Boiling wax burn in mid-autumn festival in Hong Kong.

    PubMed

    Chan, E S; Chan, E C; Ho, W S; King, W W

    1997-01-01

    An unusual cause of burn, contact with boiling wax by children and adolescents during the annual mid-autumn festival in Hong Kong is presented. 57 patients who suffered from hot wax burn over the period 1986-1996 were admitted to the Burns Unit of the Prince of Wales Hospital. This special burn should be preventable by public education. PMID:9568338

  6. MODELING OF THE FAST ORGANIC EMISSIONS FROM A WOOD-FINISHING PRODUCT -- FLOOR WAX

    EPA Science Inventory

    The paper discusses environmental chamber and full-scale residential house tests conducted to characterize the fast organic emissions from a wood finishing product, floor wax. For the environmental chamber tests, a very small amount (< 5 g/sq m) of the wax was applied to an alumi...

  7. Gelling ability and crystal morphology of sunflower wax in soybean oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant waxes can effectively form organogels with vegetable oils and these organogels have drawn considerable interests as alternatives to solid fats containing trans fats and saturated fats in margarines and spreads. Among them sunflower wax showed the most pronounced gelling ability. In an attempt ...

  8. Comb wax effects on the ontogeny of honey bee nestmate recognition

    PubMed

    Breed; Leger; Pearce; Wang

    1998-01-01

    We addressed the general question of how kin recognition cues develop by investigating cue differentiation between colonies of the honey bee, Apis mellifera. In honey bee colonies, exposure to the wax comb is a critical component of the development of kin recognition cues. In this study, we determined how the cues develop under natural conditions (in swarms), whether the genetic source and age of the wax affect cue ontogeny, and whether exposure to wax, as in normal development, affects preferential feeding among bees within social groups. Cue development in swarms coincided with wax production, rather than with the presence of brood or the emergence of new workers; this finding supported previous observations concerning the importance of wax in cue ontogeny. Effective cue development required a match between the genetic source of the workers attempting to enter the hive, the wax to which they were exposed, and the guards at the hive entrance. The wax must also have been exposed to the hive environment for some time. Cues gained from wax did not mask or override cues used in preferential feeding interactions; this finding supports the contention that two recognition systems, one for nestmate recognition and the other for intra-colonial recognition, are present. The results fit a general model for cue development in nestmate recognition that relies on the use of nesting materials as an intermediary; the evolutionary significance of this model is discussed. Copyright 1998 The Association for the Study of Animal Behaviour.

  9. Genetic mapping and characterization of an epicuticular wax (bloom) gene SbBI, in sorghum bicolor.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genes involved in wax production can have significant potential in enhancing drought tolerance in many crop species. Here, we describe the genetic mapping and characterization of the gene, bloom (Sb Bl), involved in the expression of profuse white fluffy epicuticular wax in sorghum. Genetic mapping...

  10. Evaluation of canola oil oleogels with candelilla wax as an alternative to shortening in baked goods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The oleogels of canola oil with candelilla wax were prepared and utilized as a shortening replacer to produce cookies with a high level of unsaturated fatty acids. The incorporation of candelilla wax (3 and 6% by weight) to canola oil produced the oleogels with solid-like properties. The firmness of...

  11. An in situ method for observing wax crystallization under pipe flow

    NASA Astrophysics Data System (ADS)

    Welch, Sarah E.; Mazzanti, Gianfranco; Steer, Tyrone N.; Stetzer, Mackenzie R.; Kautsky, Sacha P.; Merz, Hugh; Idziak, Stefan H. J.; Sirota, Eric B.

    2003-03-01

    As the phenomenon of wax deposition in crude oil pipelines is of great relevance to the petroleum industry, there has been considerable work on both real and model oil pipeline systems in an effort to gain insight into the deposition process itself. In an effort to develop a truly in situ means of characterizing the formation and evolution of the wax gel layers deposited in model pipeline systems, we have performed x-ray diffraction measurements of wax crystallization in wax-oil mixtures under flow. We conducted a time dependent investigation of the nucleation and growth of wax crystals and the evolution of the resulting wax gel deposit in mixtures of paraffin wax and dodecane under pipe flow through a standard x-ray quartz capillary of diameter 1mm. Our results were compared with those of larger scale, pressure drop experiments[1]. 1. Singh, P., et al., Formation and Aging of Incipient Thin Film Wax-Oil Gels. American Institute of Chemical Engineers Journal, 2000. 46(5): p. 1059-1074.

  12. WIN1, a transcriptional activator of epidermal wax accumulation in Arabidopsis

    PubMed Central

    Broun, Pierre; Poindexter, Patricia; Osborne, Erin; Jiang, Cai-Zhong; Riechmann, José Luis

    2004-01-01

    Epicuticular wax forms a layer of hydrophobic material on plant aerial organs, which constitutes a protective barrier between the plant and its environment. We report here the identification of WIN1, an Arabidopsis thaliana ethylene response factor-type transcription factor, which can activate wax deposition in overexpressing plants. We constitutively expressed WIN1 in transgenic Arabidopsis plants, and found that leaf epidermal wax accumulation was up to 4.5-fold higher in these plants than in control plants. A significant increase was also found in stems. Interestingly, ≈50% of the additional wax could only be released by complete lipid extractions, suggesting that not all of the wax is superficial. Gene expression analysis indicated that a number of genes, such as CER1, KCS1, and CER2, which are known to be involved in wax biosynthesis, were induced in WIN1 overexpressors. This observation indicates that induction of wax accumulation in transgenic plants is probably mediated through an increase in the expression of genes encoding enzymes of the wax biosynthesis pathway. PMID:15070782

  13. Economic Assessment of Supercritical CO2 Extraction of Waxes as Part of a Maize Stover Biorefinery

    PubMed Central

    Attard, Thomas M.; McElroy, Con Robert; Hunt, Andrew J.

    2015-01-01

    To date limited work has focused on assessing the economic viability of scCO2 extraction to obtain waxes as part of a biorefinery. This work estimates the economic costs for wax extraction from maize stover. The cost of manufacture (COM) for maize stover wax extraction was found to be €88.89 per kg of wax, with the fixed capital investment (FCI) and utility costs (CUT) contributing significantly to the COM. However, this value is based solely on scCO2 extraction of waxes and does not take into account the downstream processing of the biomass following extraction. The cost of extracting wax from maize stover can be reduced by utilizing pelletized leaves and combusting the residual biomass to generate electricity. This would lead to an overall cost of €10.87 per kg of wax (based on 27% combustion efficiency for electricity generation) and €4.56 per kg of wax (based on 43% combustion efficiency for electricity generation). A sensitivity analysis study showed that utility costs (cost of electricity) had the greatest effect on the COM. PMID:26263976

  14. Organogels of vegetable oil with plant wax – trans/saturated fat replacements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This featured article reviews recent advances on the development of trans fat-free, low saturated fat food products from organogels formed by a plant wax in a vegetable oil. Plant waxes are of great interest in this research area because they are obtained as by-products during the oil refining proce...

  15. The MYB96 Transcription Factor Regulates Cuticular Wax Biosynthesis under Drought Conditions in Arabidopsis[W

    PubMed Central

    Seo, Pil Joon; Lee, Saet Buyl; Suh, Mi Chung; Park, Mi-Jeong; Go, Young Sam; Park, Chung-Mo

    2011-01-01

    Drought stress activates several defense responses in plants, such as stomatal closure, maintenance of root water uptake, and synthesis of osmoprotectants. Accumulating evidence suggests that deposition of cuticular waxes is also associated with plant responses to cellular dehydration. Yet, how cuticular wax biosynthesis is regulated in response to drought is unknown. We have recently reported that an Arabidopsis thaliana abscisic acid (ABA)–responsive R2R3-type MYB transcription factor, MYB96, promotes drought resistance. Here, we show that transcriptional activation of cuticular wax biosynthesis by MYB96 contributes to drought resistance. Microarray assays showed that a group of wax biosynthetic genes is upregulated in the activation-tagged myb96-1D mutant but downregulated in the MYB96-deficient myb96-1 mutant. Cuticular wax accumulation was altered accordingly in the mutants. In addition, activation of cuticular wax biosynthesis by drought and ABA requires MYB96. By contrast, biosynthesis of cutin monomers was only marginally affected in the mutants. Notably, the MYB96 protein acts as a transcriptional activator of genes encoding very-long-chain fatty acid–condensing enzymes involved in cuticular wax biosynthesis by directly binding to conserved sequence motifs present in the gene promoters. These results demonstrate that ABA-mediated MYB96 activation of cuticular wax biosynthesis serves as a drought resistance mechanism. PMID:21398568

  16. Boiling wax burn in mid-autumn festival in Hong Kong.

    PubMed

    Chan, E S; Chan, E C; Ho, W S; King, W W

    1997-01-01

    An unusual cause of burn, contact with boiling wax by children and adolescents during the annual mid-autumn festival in Hong Kong is presented. 57 patients who suffered from hot wax burn over the period 1986-1996 were admitted to the Burns Unit of the Prince of Wales Hospital. This special burn should be preventable by public education.

  17. Economic Assessment of Supercritical CO2 Extraction of Waxes as Part of a Maize Stover Biorefinery.

    PubMed

    Attard, Thomas M; McElroy, Con Robert; Hunt, Andrew J

    2015-07-31

    To date limited work has focused on assessing the economic viability of scCO2 extraction to obtain waxes as part of a biorefinery. This work estimates the economic costs for wax extraction from maize stover. The cost of manufacture (COM) for maize stover wax extraction was found to be € 88.89 per kg of wax, with the fixed capital investment (FCI) and utility costs (CUT) contributing significantly to the COM. However, this value is based solely on scCO2 extraction of waxes and does not take into account the downstream processing of the biomass following extraction. The cost of extracting wax from maize stover can be reduced by utilizing pelletized leaves and combusting the residual biomass to generate electricity. This would lead to an overall cost of € 10.87 per kg of wax (based on 27% combustion efficiency for electricity generation) and €4.56 per kg of wax (based on 43% combustion efficiency for electricity generation). A sensitivity analysis study showed that utility costs (cost of electricity) had the greatest effect on the COM.

  18. Characterisation of wax works of art by gas chromatographic procedures.

    PubMed

    Regert, M; Langlois, J; Colinart, S

    2005-10-14

    To identify the various natural and synthetic substances used by sculptors at the end of the 19th century, several contemporary reference samples were investigated by high temperature gas chromatography (HT GC) and HT GC-MS. Using specific chromatographic conditions and minimising sample preparation, we could separate, detect and identify a wide range of biomolecular markers covering a great variety of molecular weights and volatilities, with a minimum amount of sample, in a single run. Beeswax, spermaceti, carnauba, candellila and Japan waxes as well as pine resin derivatives, animal fats, paraffin, ozokerite and stearin, used as additives in wax works of art, were chemically investigated. In the case of low volatile compounds, transbutylation was performed. The structure of long-chain esters of spermaceti was elucidated for the first time by HT GC-MS analysis. Such a method was then carried out on 10 samples collected on a statuette of Junon by Antoine-Louis Barye (Louvre Museum, Paris, France) and on a sculpture by Aimé-Jules Dalou (Musée de la Révolution Française, Vizille, France). The analytical results obtained provide new data on the complex recipes elaborated by sculptors at the end of the 19th century.

  19. Hydrocracking and recovering polynuclear aromatic compounds in slop wax stream

    SciTech Connect

    Gruia, A.J.

    1987-10-06

    This patent describes a catalytic hydrocracking process which comprises: (a) introducing a reduced crude into a fractionation zone to produce a vacuum gas oil stream having a propensity to form polynuclear aromatic compounds in a hydrocracking zone and a slop wax stream; (b) contacting the vacuum gas oil stream in a hydrocracking zone with added hydrogen and a metal promoted hydrocracking catalyst at elevated temperature and pressure sufficient to gain a substantial conversion to lower boiling products; (c) partially condensing the hydrocarbon effluent from the hydrocracking zone and separating the same into a low boiling hydrocarbon product stream and an unconverted hydrocarbon stream boiling above about 650/sup 0/F (343/sup 0/C) and containing trace quantities of polynuclear aromatic compounds; and (d) introducing at least a portion of the unconverted hydrocarbon stream containing polynuclear aromatic compounds into the fractionation zone thereby recovering a substantial portion of the polynuclear aromatic compounds in the slop wax stream which significantly minimizes the introduction of the polynuclear aromatic compounds into the hydrocracking zone.

  20. Investigating molecular interactions and surface morphology of wax-doped asphaltenes.

    PubMed

    Pahlavan, Farideh; Mousavi, Masoumeh; Hung, Albert; Fini, Ellie H

    2016-04-01

    The nature and origin of bee-like microstructures (bees) in asphalt binders and their impact on asphalt oxidation have been the subject of extensive discussions in recent years. While several studies refer to the bees as solely surface features, some others consider them to be bulk microcrystalline components that are formed due to co-precipitation of wax and asphaltene molecules. In this study, we use a rigorous theoretical and experimental approach to investigate the interplay of asphalt components (mainly asphaltene and wax) and their impact on bee formation. In the theoretical section, quantum-mechanical calculations using density functional theory (DFT) are used to evaluate the strength of interactions between asphaltene unit sheets in the presence and absence of a wax component, as well as the mutual interactions between asphaltene molecules (monomers and dimers) and paraffin wax. The results of this section reveal that paraffin waxes not only do not reinforce the interaction between the asphaltene unit sheets, they destabilize asphaltene assembly and dimerization. AIM (Atom in Molecules) analysis shows the destabilizing effect of wax on asphaltene assembly as a reduction in the number of cage and bond critical points between asphaltenes. This destabilization effect among interacting systems (asphaltene-asphaltene and wax-asphaltene) does not support the hypothesis that interaction between paraffin waxes and non-wax components, such as asphaltene, is responsible for their co-precipitation and bee formation. To further examine the effect of wax component on asphalt microstructure experimentally, we used atomic force microscopy (AFM) to study the surface morphology of an asphalt sample doped with 1% to 25% paraffin wax. In agreement with the conclusions drawn from the DFT approach, our experiments indicate that paraffin wax tends to crystallize separately and form lamellar paraffin wax crystal inclusions with 10 nm thickness. Moreover, the addition of 3% wax

  1. Investigating molecular interactions and surface morphology of wax-doped asphaltenes.

    PubMed

    Pahlavan, Farideh; Mousavi, Masoumeh; Hung, Albert; Fini, Ellie H

    2016-04-01

    The nature and origin of bee-like microstructures (bees) in asphalt binders and their impact on asphalt oxidation have been the subject of extensive discussions in recent years. While several studies refer to the bees as solely surface features, some others consider them to be bulk microcrystalline components that are formed due to co-precipitation of wax and asphaltene molecules. In this study, we use a rigorous theoretical and experimental approach to investigate the interplay of asphalt components (mainly asphaltene and wax) and their impact on bee formation. In the theoretical section, quantum-mechanical calculations using density functional theory (DFT) are used to evaluate the strength of interactions between asphaltene unit sheets in the presence and absence of a wax component, as well as the mutual interactions between asphaltene molecules (monomers and dimers) and paraffin wax. The results of this section reveal that paraffin waxes not only do not reinforce the interaction between the asphaltene unit sheets, they destabilize asphaltene assembly and dimerization. AIM (Atom in Molecules) analysis shows the destabilizing effect of wax on asphaltene assembly as a reduction in the number of cage and bond critical points between asphaltenes. This destabilization effect among interacting systems (asphaltene-asphaltene and wax-asphaltene) does not support the hypothesis that interaction between paraffin waxes and non-wax components, such as asphaltene, is responsible for their co-precipitation and bee formation. To further examine the effect of wax component on asphalt microstructure experimentally, we used atomic force microscopy (AFM) to study the surface morphology of an asphalt sample doped with 1% to 25% paraffin wax. In agreement with the conclusions drawn from the DFT approach, our experiments indicate that paraffin wax tends to crystallize separately and form lamellar paraffin wax crystal inclusions with 10 nm thickness. Moreover, the addition of 3% wax

  2. How polymer additives reduce the pour point of hydrocarbon solvents containing wax crystals.

    PubMed

    Binks, Bernard P; Fletcher, Paul D I; Roberts, Noel A; Dunkerley, John; Greenfield, Hannah; Mastrangelo, Antonio; Trickett, Kieran

    2015-02-14

    We have investigated how four different pour point depressant (PPD) polymers affect the pour point transition in mixtures of a single pure wax in a solvent. We used either n-eicosane (C20), CH3(CH2)18CH3, n-tetracosane (C24), CH3(CH2)22CH3 or n-hexatriacontane (C36), CH3(CH2)34CH3 as the wax component with either n-heptane or toluene as the solvent component. For all wax-solvent combinations, the measured variation of wax solubility with temperature is well predicted by ideal solution theory. The variation of pour point temperature as a function of the overall wax concentration is quantitatively modelled using the idea that, for each overall wax concentration, the pour point occurs at a temperature at which a critical volume fraction ϕ* of wax crystals has precipitated. Close to the pour point temperature, extraction and examination of the wax crystals show they consist of polydisperse, irregularly-shaped platelets with axial ratios (h/d, where h is the plate thickness and d is the plate long dimension) in the range 0.005-0.05. It is found that the measured ϕ* values corresponding to the pour point transitions are weakly correlated with the wax crystal axial ratios (h/d) for all wax-solvent-PPD polymer combinations. These results indicate that the pour point transition occurs at a volume fraction larger than the value at which the volumes of rotation of the platelet crystals overlap, i.e., 2.5(h/d) < ϕ* < 11(h/d). PPD polymers work, in part, by increasing the wax crystal axial ratio (h/d), thereby increasing ϕ* and reducing the pour point temperature. Since the PPD's ability to modify the wax crystal shape relies on its adsorption to the crystal-solution surface, it is anticipated and observed experimentally that optimum PPD efficacy is correlated with the difference between the wax and the polymer solubility boundary temperatures. This finding and the mechanistic insight gained here provide the basis for a simple and rapid screening test to identify candidate

  3. How polymer additives reduce the pour point of hydrocarbon solvents containing wax crystals.

    PubMed

    Binks, Bernard P; Fletcher, Paul D I; Roberts, Noel A; Dunkerley, John; Greenfield, Hannah; Mastrangelo, Antonio; Trickett, Kieran

    2015-02-14

    We have investigated how four different pour point depressant (PPD) polymers affect the pour point transition in mixtures of a single pure wax in a solvent. We used either n-eicosane (C20), CH3(CH2)18CH3, n-tetracosane (C24), CH3(CH2)22CH3 or n-hexatriacontane (C36), CH3(CH2)34CH3 as the wax component with either n-heptane or toluene as the solvent component. For all wax-solvent combinations, the measured variation of wax solubility with temperature is well predicted by ideal solution theory. The variation of pour point temperature as a function of the overall wax concentration is quantitatively modelled using the idea that, for each overall wax concentration, the pour point occurs at a temperature at which a critical volume fraction ϕ* of wax crystals has precipitated. Close to the pour point temperature, extraction and examination of the wax crystals show they consist of polydisperse, irregularly-shaped platelets with axial ratios (h/d, where h is the plate thickness and d is the plate long dimension) in the range 0.005-0.05. It is found that the measured ϕ* values corresponding to the pour point transitions are weakly correlated with the wax crystal axial ratios (h/d) for all wax-solvent-PPD polymer combinations. These results indicate that the pour point transition occurs at a volume fraction larger than the value at which the volumes of rotation of the platelet crystals overlap, i.e., 2.5(h/d) < ϕ* < 11(h/d). PPD polymers work, in part, by increasing the wax crystal axial ratio (h/d), thereby increasing ϕ* and reducing the pour point temperature. Since the PPD's ability to modify the wax crystal shape relies on its adsorption to the crystal-solution surface, it is anticipated and observed experimentally that optimum PPD efficacy is correlated with the difference between the wax and the polymer solubility boundary temperatures. This finding and the mechanistic insight gained here provide the basis for a simple and rapid screening test to identify candidate

  4. System and method for the mitigation of paraffin wax deposition from crude oil by using ultrasonic waves

    SciTech Connect

    Towler, Brian F.

    2007-09-04

    A method for mitigating the deposition of wax on production tubing walls. The method comprises positioning at least one ultrasonic frequency generating device adjacent the production tubing walls and producing at least one ultrasonic frequency thereby disintegrating the wax and inhibiting the wax from attaching to the production tubing walls. A system for mitigating the deposition of wax on production tubing walls is also provided.

  5. Rapid analysis of 13C in plant-wax n-alkanes for reconstruction of terrestrial vegetation signals from aquatic sediments

    NASA Astrophysics Data System (ADS)

    McDuffee, Kelsey E.; Eglinton, Timothy I.; Sessions, Alex L.; Sylva, Sean; Wagner, Thomas; Hayes, John M.

    2004-10-01

    Long-chain, odd-carbon-numbered C25 to C35n-alkanes are characteristic components of epicuticular waxes produced by terrestrial higher plants. They are delivered to aquatic systems via eolian and fluvial transport and are preserved in underlying sediments. The isotopic compositions of these products can serve as records of past vegetation. We have developed a rapid method for stable carbon isotopic analyses of total plant-wax n-alkanes using a novel, moving-wire system coupled to an isotope-ratio mass spectrometer (MW-irMS). The n-alkane fractions are prepared from sediment samples by (1) saponification and extraction with organic solvents, (2) chromatographic separation using silica gel, (3) isolation of straight-chain carbon skeletons using a zeolite molecular sieve, and (4) oxidation and removal of unsaturated hydrocarbons with RuO4. Short-chain n-alkanes of nonvascular plant origin (wax n-alkanes. The amplitude of the variations was smaller, indicating contributions from non-plant-wax hydrocarbons, but the measurements revealed variations in carbon isotopic composition that are consistent with vegetation zones on the adjacent continent.

  6. Rapid analysis of 13C in plant-wax n-alkanes for reconstruction of terrestrial vegetation signals from aquatic sediments

    NASA Astrophysics Data System (ADS)

    McDuffee, Kelsey E.; Eglinton, Timothy I.; Sessions, Alex L.; Sylva, Sean; Wagner, Thomas; Hayes, John M.

    2004-10-01

    Long-chain, odd-carbon-numbered C25 to C35 n-alkanes are characteristic components of epicuticular waxes produced by terrestrial higher plants. They are delivered to aquatic systems via eolian and fluvial transport and are preserved in underlying sediments. The isotopic compositions of these products can serve as records of past vegetation. We have developed a rapid method for stable carbon isotopic analyses of total plant-wax n-alkanes using a novel, moving-wire system coupled to an isotope-ratio mass spectrometer (MW-irMS). The n-alkane fractions are prepared from sediment samples by (1) saponification and extraction with organic solvents, (2) chromatographic separation using silica gel, (3) isolation of straight-chain carbon skeletons using a zeolite molecular sieve, and (4) oxidation and removal of unsaturated hydrocarbons with RuO4. Short-chain n-alkanes of nonvascular plant origin (wax n-alkanes. The amplitude of the variations was smaller, indicating contributions from non-plant-wax hydrocarbons, but the measurements revealed variations in carbon isotopic composition that are consistent with vegetation zones on the adjacent continent.

  7. Geographically Related Variation in Epicuticular Wax Traits of Pinus nigra Populations from Southern Carpathians and Central Balkans - Taxonomic Considerations.

    PubMed

    Mitić, Zorica S; Zlatković, Bojan K; Jovanović, Snežana Č; Stojanović, Gordana S; Marin, Petar D

    2016-07-01

    The chemical composition of epicuticular waxes of nine populations from three Pinus nigra J. F. Arnold subspecies (namely subsp. nigra, subsp. banatica (Borbás) Novák, and subsp. pallasiana (Lamb.) Holmboe) from Southern Carpathians and central Balkan Peninsula were analyzed using GC/MS and GC/FID chromatography, and multivariate statistical techniques with respect to biogeography and taxonomy. In the needle waxes, four primary alcohols and 14 n-alkanes ranging from C21 to C33 were identified, and the most abundant compounds were the four odd-numbered n-alkanes C27 , C25 , C23 , and C29. Multivariate statistical analyses (CDA and CA) have shown existence of three P. nigra groups and suggested clinal differentiation as a mechanism of genetic variation across a geographic area: the first group consisted of the southernmost populations of subsp. pallasiana from Macedonia, the second consisted of the northernmost subsp. banatica populations from Romania, while all populations in Serbia described as three different subspecies (nigra, banatica, and pallasiana) formed the third group together with subsp. nigra population from Bosnia and Herzegovina. According to simple linear regression, geographic latitude and four bioclimatic parameters were moderately correlated with the contents of epicuticular wax compounds that are important in population discrimination, while stepwise multiple regression showed that latitude participated in most of the regression models for predicting the composition of the epicuticular waxes. These results agree with CDA and CA analysis, and confirmed the possibility of recognition of fine geographic differentiation of the analyzed P. nigra populations. PMID:27273147

  8. FT-IR analysis of phosphorylated protein

    NASA Astrophysics Data System (ADS)

    Ishii, Katsunori; Yoshihashi, Sachiko S.; Chihara, Kunihiro; Awazu, Kunio

    2004-09-01

    Phosphorylation and dephosphorylation, which are the most remarkable posttranslational modifications, are considered to be important chemical reactions that control the activation of proteins. We examine the phosphorylation analysis method by measuring the infrared absorption peak of phosphate group that observed at about 1070cm-1 (9.4μm) with Fourier Transform Infrared Spectrometer (FT-IR). This study indicates that it is possible to identify a phosphorylation by measuring the infrared absorption peak of phosphate group observed at about 1070 cm-1 with FT-IR method. As long as target peptides have the same amino acid sequence, it is possible to identify the phosphorylated sites (threonine, serine and tyrosine).

  9. Direct chemical profiling of olive (Olea europaea) fruit epicuticular waxes by direct electrospray-ultrahigh resolution mass spectrometry.

    PubMed

    Vichi, Stefania; Cortés-Francisco, Nuria; Romero, Agustí; Caixach, Josep

    2015-03-01

    In the present paper, an electrospray ionization (ESI)-Orbitrap method is proposed for the direct chemical profiling of epicuticular wax (EW) from Olea europaea fruit. It constitutes a rapid and efficient tool suitable for a wide-ranging screening of a large number of samples. In a few minutes, the method provides a comprehensive characterization of total EW extracts, based on the molecular formula of their components. Accurate mass measurements are obtained by ultrahigh resolution mass spectrometry, and compositional restrictions are set on the basis of the information available from previous studies of olive EW. By alternating positive and negative ESI modes within the same analysis, complementary results are obtained and a wide range of chemical species is covered. This provides a detailed compositional overview that otherwise would only be available by applying multiple analytical techniques.

  10. Biodegradation of paraffin wax by crude Aspergillus enzyme preparations for potential use in removing paraffin deposits.

    PubMed

    Zhang, Junhui; Xue, Quanhong; Gao, Hui; Wang, Ping

    2015-11-01

    Paraffin deposition problems have plagued the oil industry. Whist mechanical and chemical methods are problematic, microbiological method of paraffin removal is considered an alternative. However, studies have mainly investigated the use of bacteria, with little attention to the potential of fungi. The performance of six Aspergillus isolates to degrade paraffin wax was evaluated under laboratory conditions using solid enzyme preparations. The results showed that all the six enzyme preparations efficiently improved the solubility of paraffin wax in n-hexane and degraded n-alkanes in paraffin wax. The degradation process was accompanied by dynamic production of gases (CO2 and H2 ) and organic acids (oxalate and propionate). The shape of wax crystals markedly changed after enzymatic degradation, with a rough surface and a loose structure. This study indicates that extracellular enzymes from Aspergillus spp. can efficiently degrade paraffin wax. These enzyme preparations have the potential for use in oil wells with paraffin deposition problems.

  11. Biodegradation of paraffin wax by crude Aspergillus enzyme preparations for potential use in removing paraffin deposits.

    PubMed

    Zhang, Junhui; Xue, Quanhong; Gao, Hui; Wang, Ping

    2015-11-01

    Paraffin deposition problems have plagued the oil industry. Whist mechanical and chemical methods are problematic, microbiological method of paraffin removal is considered an alternative. However, studies have mainly investigated the use of bacteria, with little attention to the potential of fungi. The performance of six Aspergillus isolates to degrade paraffin wax was evaluated under laboratory conditions using solid enzyme preparations. The results showed that all the six enzyme preparations efficiently improved the solubility of paraffin wax in n-hexane and degraded n-alkanes in paraffin wax. The degradation process was accompanied by dynamic production of gases (CO2 and H2 ) and organic acids (oxalate and propionate). The shape of wax crystals markedly changed after enzymatic degradation, with a rough surface and a loose structure. This study indicates that extracellular enzymes from Aspergillus spp. can efficiently degrade paraffin wax. These enzyme preparations have the potential for use in oil wells with paraffin deposition problems. PMID:26265455

  12. Quantitative Evaluation of Tissue Surface Adaption of CAD-Designed and 3D Printed Wax Pattern of Maxillary Complete Denture

    PubMed Central

    Chen, Hu; Wang, Han; Lv, Peijun; Wang, Yong; Sun, Yuchun

    2015-01-01

    Objective. To quantitatively evaluate the tissue surface adaption of a maxillary complete denture wax pattern produced by CAD and 3DP. Methods. A standard edentulous maxilla plaster cast model was used, for which a wax pattern of complete denture was designed using CAD software developed in our previous study and printed using a 3D wax printer, while another wax pattern was manufactured by the traditional manual method. The cast model and the two wax patterns were scanned in the 3D scanner as “DataModel,” “DataWaxRP,” and “DataWaxManual.” After setting each wax pattern on the plaster cast, the whole model was scanned for registration. After registration, the deviations of tissue surface between “DataModel” and “DataWaxRP” and between “DataModel” and “DataWaxManual” were measured. The data was analyzed by paired t-test. Results. For both wax patterns produced by the CAD&RP method and the manual method, scanning data of tissue surface and cast surface showed a good fit in the majority. No statistically significant (P > 0.05) difference was observed between the CAD&RP method and the manual method. Conclusions. Wax pattern of maxillary complete denture produced by the CAD&3DP method is comparable with traditional manual method in the adaption to the edentulous cast model. PMID:26583108

  13. Understanding wax screen-printing: a novel patterning process for microfluidic cloth-based analytical devices.

    PubMed

    Liu, Min; Zhang, Chunsun; Liu, Feifei

    2015-09-01

    In this work, we first introduce the fabrication of microfluidic cloth-based analytical devices (μCADs) using a wax screen-printing approach that is suitable for simple, inexpensive, rapid, low-energy-consumption and high-throughput preparation of cloth-based analytical devices. We have carried out a detailed study on the wax screen-printing of μCADs and have obtained some interesting results. Firstly, an analytical model is established for the spreading of molten wax in cloth. Secondly, a new wax screen-printing process has been proposed for fabricating μCADs, where the melting of wax into the cloth is much faster (∼5 s) and the heating temperature is much lower (75 °C). Thirdly, the experimental results show that the patterning effects of the proposed wax screen-printing method depend to a certain extent on types of screens, wax melting temperatures and melting time. Under optimized conditions, the minimum printing width of hydrophobic wax barrier and hydrophilic channel is 100 μm and 1.9 mm, respectively. Importantly, the developed analytical model is also well validated by these experiments. Fourthly, the μCADs fabricated by the presented wax screen-printing method are used to perform a proof-of-concept assay of glucose or protein in artificial urine with rapid high-throughput detection taking place on a 48-chamber cloth-based device and being performed by a visual readout. Overall, the developed cloth-based wax screen-printing and arrayed μCADs should provide a new research direction in the development of advanced sensor arrays for detection of a series of analytes relevant to many diverse applications. PMID:26388382

  14. Understanding wax screen-printing: a novel patterning process for microfluidic cloth-based analytical devices.

    PubMed

    Liu, Min; Zhang, Chunsun; Liu, Feifei

    2015-09-01

    In this work, we first introduce the fabrication of microfluidic cloth-based analytical devices (μCADs) using a wax screen-printing approach that is suitable for simple, inexpensive, rapid, low-energy-consumption and high-throughput preparation of cloth-based analytical devices. We have carried out a detailed study on the wax screen-printing of μCADs and have obtained some interesting results. Firstly, an analytical model is established for the spreading of molten wax in cloth. Secondly, a new wax screen-printing process has been proposed for fabricating μCADs, where the melting of wax into the cloth is much faster (∼5 s) and the heating temperature is much lower (75 °C). Thirdly, the experimental results show that the patterning effects of the proposed wax screen-printing method depend to a certain extent on types of screens, wax melting temperatures and melting time. Under optimized conditions, the minimum printing width of hydrophobic wax barrier and hydrophilic channel is 100 μm and 1.9 mm, respectively. Importantly, the developed analytical model is also well validated by these experiments. Fourthly, the μCADs fabricated by the presented wax screen-printing method are used to perform a proof-of-concept assay of glucose or protein in artificial urine with rapid high-throughput detection taking place on a 48-chamber cloth-based device and being performed by a visual readout. Overall, the developed cloth-based wax screen-printing and arrayed μCADs should provide a new research direction in the development of advanced sensor arrays for detection of a series of analytes relevant to many diverse applications.

  15. Waxing and Waning of Forests: Late Quaternary Biogeography of Lake Malawi, Southeast Africa

    NASA Astrophysics Data System (ADS)

    Ivory, S.; Lézine, A. M.; Vincens, A.; Cohen, A. S.

    2014-12-01

    African ecosystems are at great risk due to climate and land-use change. Despite the status of several of these regions as biodiversity hotspots, long-standing ideas about African ecology and biogeography have been unable to be tested until now due to lack of sufficiently long records. Here, we present the first long, continuous terrestrial record of vegetation from Lake Malawi, East Africa which goes back to the early Late Quaternary, permitting us to investigate changes in physiognomy and forest composition over many transitions. In this record, we observe eight phases of forest expansion and collapse. Although diversity is much greater during forest phases, composition varies little from phase to phase. Very high abundances of afromontane taxa suggest frequent widespread colonization of the lowlands by modern high elevation trees. Although there are clear successional stages within each forest such that turnover is great within a single phase, among forest samples between phases, there is little dissimilarity. Each forest phase is interrupted by rapid decline of arboreal taxa and expansion of semi-arid grasslands or woodlands whose composition varies greatly from phase to phase. The variable composition of the more open phases, all occurring during arid periods, is likely dynamically linked to thresholds in regional hydrology associated with lake level and moisture recycling within the watershed. This vegetation is unlike any found at Malawi today, with assemblages suggesting strong Somali-Masai affinities. Furthermore, nearly all semi-arid assemblages contain small abundances of forest taxa typically growing in areas with wetter edaphic conditions, suggesting that moist lowland gallery forests were present but restricted to waterways during exceptionally arid times. The waxing and waning of forests throughout this interval has important implications for early human biogeography across Africa as well as disturbance regimes that are crucial for the maintenance of

  16. FT 3 Flight Test Cards for Export

    NASA Technical Reports Server (NTRS)

    Marston, Michael L.

    2015-01-01

    These flight test cards will be made available to stakeholders who participated in FT3. NASA entered into the relationship with our stakeholders, including the FAA, to develop requirements that will lead to routine flights of unmanned aircraft systems flying in the national airspace system.

  17. Preparation and characterization of PEG-PPG-PEG copolymer/pregelatinized starch blends for use as resorbable bone hemostatic wax.

    PubMed

    Suwanprateeb, J; Suvannapruk, W; Thammarakcharoen, F; Chokevivat, W; Rukskul, P

    2013-12-01

    In this study, polymer blends between PEG-PPG-PEG copolymer mixtures and pregelatinized starch at various compositions ranging from 0 to 3 % by weight were prepared and evaluated for potential use as novel resorbable bone hemostatic wax. It was found that the prepared samples had sufficient smearability for use as a bone wax. An addition of pregelatinized starch increased the hardness, smoothness and consistency of the texture while decreasing the adherence to glove. Thermal analysis indicated that the heat of fusion slightly decreased with increasing pregelatinized starch content. Compressive stiffness tended to decrease with increasing starch content for concentrations lower than 20 %, but re-increased at higher starch levels. In contrast, adherence deformation increased initially, but then decreased with increasing starch content. This behavior was related to the dependence of softening or reinforcing effect on the level of starch concentration in the samples. Adherence load and energy decreased with the addition of pregelatinized starch implying the decrease in adhesiveness of the samples. Furthermore, increasing the pregelatized starch amount also increased the liquid sealing duration of the samples at both 23 and 37 °C. Cytotoxicity tests against osteoblasts using a MTT assay revealed that the all the prepared samples and their raw materials did not show any cytotoxic potential. Formulations containing pregelatinized starch content between 20 and 30 % were found to show optimized performance. PMID:23955721

  18. High Yield of Wax Ester Synthesized from Cetyl Alcohol and Octanoic Acid by Lipozyme RMIM and Novozym 435

    PubMed Central

    Kuo, Chia-Hung; Chen, Hsin-Hung; Chen, Jiann-Hwa; Liu, Yung-Chuan; Shieh, Chwen-Jen

    2012-01-01

    Wax esters are long-chain esters that have been widely applied in premium lubricants, parting agents, antifoaming agents and cosmetics. In this study, the biocatalytic preparation of a specific wax ester, cetyl octanoate, is performed in n-hexane using two commercial immobilized lipases, i.e., Lipozyme® RMIM (Rhizomucor miehei) and Novozym® 435 (Candida antarctica). Response surface methodology (RSM) and 5-level-4-factor central composite rotatable design (CCRD) are employed to evaluate the effects of reaction time (1–5 h), reaction temperature (45–65 °C), substrate molar ratio (1–3:1), and enzyme amount (10%–50%) on the yield of cetyl octanoate. Using RSM to optimize the reaction, the maximum yields reached 94% and 98% using Lipozyme® RMIM and Novozym® 435, respectively. The optimum conditions for synthesis of cetyl octanoate by both lipases are established and compared. Novozym® 435 proves to be a more efficient biocatalyst than Lipozyme® RMIM. PMID:23109878

  19. Physical behavior of purified and crude wax obtained from sunflower (Helianthus annuus) seed oil refineries and seed hulls.

    PubMed

    Kanya, T C Sindhu; Sankar, K Udaya; Sastry, M C Shamnathaka

    2003-01-01

    The sunflower seed waxes obtained from two sources (i) seed hull as a standard and (ii) crude wax from oil refineries were studied for their crystallization, melting characteristics and morphology of crystals. The results of differential scanning calorimetry of wax obtained from seed hulls showed the melting temperature range of 13.18 degrees C with the onset at 62.32 degrees C, for purified wax, compared to the melting range of 24.73 degrees C with the onset at 42.3 degrees C. for crude wax. The enthalpy of fusion for both waxes were 57.55 mcal/mg and 7.63 mcal/mg, respectively. The DSC melt crystallization temperature range was 15.79 degrees C with the onset of 64.58 degrees C for purified wax and temperature range of 31.45 degrees C with an onset of 57.76 degrees C for crude wax. A similar pattern was observed of wax obtained from the crude wax of oil refineries. The enthalpy of crystallization was -64.27 mcal/mg and -7.67 mcal/mg, respectively. The purified wax obtained from the two sources (i) and (ii) were comparable with completion temperatures of 75.5 degrees C and 75.1 degrees C, respectively. The effect of inhibitor (lecithin) on crystallization of purified wax under light microscope and surface structure by scanning electron microscope were observed. Lecithin at 0.2% inhibited the crystallization but nucleation was unaltered. The wax crystal was inhibited to around 60% of the original size with 0.2% lecithin. It is concluded that the sunflower waxes studied were not comparable in their crystal properties of crude and purified states. Lecithin inhibited the crystallization of sunflower seed wax.

  20. Structural analysis of wheat wax (Triticum aestivum, c.v. 'Naturastar' L.): from the molecular level to three dimensional crystals.

    PubMed

    Koch, K; Barthlott, W; Koch, S; Hommes, A; Wandelt, K; Mamdouh, W; De-Feyter, S; Broekmann, P

    2006-01-01

    In order to elucidate the self assembly process of plant epicuticular waxes, and the molecular arrangement within the crystals, re-crystallisation of wax platelets was studied on biological and non-biological surfaces. Wax platelets were extracted from the leaf blades of wheat (Triticum aestivum L., c.v. 'Naturastar', Poaceae). Waxes were analysed by gas chromatography (GC) and mass spectrometry (MS). Octacosan-1-ol was found to be the most abundant chemical component of the wax mixture (66 m%) and also the determining compound for the shape of the wax platelets. The electron diffraction pattern showed that both the wax mixture and pure octacosan-1-ol are crystalline. The re-crystallisation of the natural wax mixture and the pure octacosan-1-ol were studied by scanning tunnelling microscopy (STM), atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Crystallisation of wheat waxes and pure octacosano-1-ol on the non polar highly ordered pyrolytic graphite (HOPG) led to the formation of platelet structures similar to those found on the plant surface. In contrast, irregular wax morphologies and flat lying plates were formed on glass, silicon, salt crystals (NaCl) and mica surfaces. Movement of wheat wax through isolated Convallaria majalis cuticles led to typical wax platelets of wheat, arranged in the complex patterns typical for C. majalis. STM of pure octacosan-1-ol monolayers on HOPG showed that the arrangement of the molecules strictly followed the hexagonal structure of the substrate crystal. Re-crystallisation of wheat waxes on non-polar crystalline HOPG substrate showed that technical surfaces could be used to generate microstructured, biomimetic surfaces. AFM and SEM studies proved that a template effect of the substrate determined the orientation of the re-grown crystals. These effects of the structure and polarity of the substrate on the morphology of the epicuticular waxes are relevant for

  1. Predicting the Hydrogen Isotope Ratios of Leaf Waxes Across Landscapes

    NASA Astrophysics Data System (ADS)

    Tipple, B. J.; Berke, M. A.; Hambach, B.; Ehleringer, J. R.

    2014-12-01

    Leaf wax n-alkanes 2H/1H ratios are widely used as a proxy of paleoprecipitation in climate reconstruction. While the broad nature of the relationships between n-alkane δ2H values and climate are appreciated on geologic scales, the quantitative details of what this proxy is reflecting remain ambiguous on plant and ecosystem levels. Areas of uncertainty on these smaller scales of importance to geologic interpretations are both the biosynthetic fractionation and the leaf-growth interval that is recorded by the isotope signal. To clarify these details, we designed a series of experiments in which modern plants were grown under controlled and monitored conditions. To determine the biosynthetic fractionation, we analyzed n-alkanes from plant grown hydroponically on isotopically distinct waters and under contrasting and controlled humidities. We observed δ2H values of n-alkane were linearly related to growth water δ2H values, but with slope differences associated with humidity. These findings suggested leaf water were central controls on δ2H values of n-alkane and support a relatively constant biosynthetic fractionation factor between leaf water and n-alkanes. To determine the interval that the leaf wax isotope signal reflects, we studied a species naturally growing on water with a constant δ2H value. Here we found the δ2H values of n-alkanes recorded only a two-week period during leaf flush and did not vary thereafter. These data indicated the δ2H values of n-alkanes record conditions early in the season, rather than integrating over the entire growing season. Using these data, we are beginning to develop geospatial predictions of the δ2H values of n-alkane across landscapes for given climate conditions, plant phenologies, and ecosystems. These emerging modeling tools may be used to assess modern ecosystem dynamics, to estimate weathering of leaf waxes to geologic repositories, and to define and test paleoclimate reconstructions from the δ2H values of n-alkanes.

  2. Removal of wax and stickies from OCC by flotation. Progress report No. 2, April 1--June 30, 1998

    SciTech Connect

    Doshi, M.R.; Dyer, J.; Heise, O.

    1998-08-01

    During the second quarter of the study the authors examined the conditions necessary for repulping a mixture of wax-coated boards that would be conducive to the flotation of detached wax. Also important for the economic viability of a waxed-board repulping process is adequate defibering of the recovered paper. Several methods for the dewaxing of pulped waxed-boards were investigated. The authors have continued to survey the literature to determine what other efforts are being made to ameliorate the impact of waxed boards during the recycling of OCC.

  3. Macrofossil and Leaf Wax Biomarkers Reveal Vegetational and Climate History of Tamarack Pond, Black Rock Forest, Southeastern New York

    NASA Astrophysics Data System (ADS)

    Alt, M.; Peteet, D. M.; Nichols, J. E.

    2014-12-01

    Tamarack Pond (41.39500°N 74.02505°W) is located at an elevation of 1305 ft, within the variable topography (Fig. 3) of Black Rock Forest, a 3830-acre oak (Quercus) dominated forest located in the Hudson Highlands Physiographic Province in southeastern New York State. A 7.2 m core retrieved in 4 m of water with a modified Livingstone piston corer was subsampled at 2 and 4-cm intervals from the base of the core through the early Holocene. The basal date of 16, 200 cal. yr BP on Dryas integrifolia leaves in inorganic clays demonstrates the pond formation in a landscape of sparse tundra with Salix, Daphnia, and craneflies. Subsequent inorganic layers record Dryas, Salix, Alnus, Polytrichum juniperum, Sphagnum, and bryozoan statoblasts. A dramatic shift to 25% organic matter in the pond records Picea needles and the first record of charcoal. Continued increases in LOI in the pond are correlative with the presence of Abies balsamea and Betula papyrifera appears as the boreal forest develops and tundra disappears. A return to colder conditions is suggested with a slight decline in LOI as Betula glandulosa and Larix laricina are present along with the boreal mixture, and a large increase in Daphnia ephippia. A return to warmer conditions ensues with the decline of the boreal conifers and the presence of Tsuga canadensis. Leaf wax data will be presented along with the macrofossil results.

  4. Development of formulations and processes to incorporate wax oleogels in ice cream.

    PubMed

    Zulim Botega, Daniele C; Marangoni, Alejandro G; Smith, Alexandra K; Goff, H Douglas

    2013-12-01

    The objective of this study was to investigate the influence of emulsifiers, waxes, fat concentration, and processing conditions on the application of wax oleogel to replace solid fat content and create optimal fat structure in ice cream. Ice creams with 10% or 15% fat were formulated with rice bran wax (RBW), candelilla wax (CDW), or carnauba wax (CBW) oleogels, containing 10% wax and 90% high-oleic sunflower oil. The ice creams were produced using batch or continuous freezing processes. Transmission electron microscopy (TEM) and cryo-scanning electron microscopy were used to evaluate the microstructure of ice cream and the ultrastructure of oleogel droplets in ice cream mixes. Among the wax oleogels, RBW oleogel had the ability to form and sustain structure in 15% fat ice creams when glycerol monooleate (GMO) was used as the emulsifier. TEM images revealed that the high degree of fat structuring observed in GMO samples was associated with the RBW crystal morphology within the fat droplet, which was characterized by the growth of crystals at the outer edge of the droplet. Continuous freezing improved fat structuring compared to batch freezing. RBW oleogels established better structure compared to CDW or CBW oleogels. These results demonstrate that RBW oleogel has the potential to develop fat structure in ice cream in the presence of GMO and sufficiently high concentrations of oleogel. PMID:24329951

  5. Thermal behavior of gamma-irradiated low-density polyethylene/paraffin wax blend

    NASA Astrophysics Data System (ADS)

    Abdou, Saleh M.; Elnahas, H. H.; El-Zahed, H.; Abdeldaym, A.

    2016-05-01

    The thermal properties of low-density polyethylene (LDPE)/paraffin wax blends were studied using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and melt flow index (MFI). Blends of LDPE/wax in ratios of 100/0, 98/2, 96/4, 94/6, 92/8, 90/10 and 85/15 (w/w) were prepared by melt-mixing at the temperature of 150°C. It was found that increasing the wax content more than 15% leads to phase separation. DSC results showed that for all blends both the melting temperature (Tm) and the melting enthalpy (ΔHm) decrease linearly with an increase in wax content. TGA analysis showed that the thermal stability of all blends decreases linearly with increasing wax content. No clear correlation was observed between the melting point and thermal stability. Horowitz and Metzger method was used to determine the thermal activation energy (Ea). MFI increased exponentially by increasing the wax content. The effect of gamma irradiation on the thermal behavior of the blends was also investigated at different gamma irradiation doses. Significant correlations were found between the thermal parameters (Tm, ΔHm, T5%, Ea and MFI) and the amount of wax content and gamma irradiation.

  6. Fabrication of biofunctionalized microfluidic structures by low-temperature wax bonding.

    PubMed

    Díaz-González, María; Baldi, Antoni

    2012-09-18

    In this work, a new fabrication technology for microfluidics based on the use of wax is described. Microfluidic structures are assembled using wax as both a thermoplastic adhesive layer between two glass substrates and a spacer layer defining the microchannels. Wax patterns with dimensions down to 25 μm are easily produced on glass substrates using specially developed decal-transfer microlithography. A complete microfluidic system is created by bonding the wax patterned layer with an additional glass substrate. On the basis of the special melting behavior of waxes, an effective glass-wax bonding is achieved at 40 °C by applying a soft pressure and without the requirement of any glass pretreatment. Wax bonding provides an effective sealing of the fluidic networks even on nonflat glass substrates (i.e., containing metal electrodes). The mild conditions required for the bonding process enables the fabrication of lab-on-a-chip devices incorporating biomolecules, as is demonstrated with the implementation of a simple heterogeneous immunoassay in a microfluidic device with amperometric detection.

  7. Development of formulations and processes to incorporate wax oleogels in ice cream.

    PubMed

    Zulim Botega, Daniele C; Marangoni, Alejandro G; Smith, Alexandra K; Goff, H Douglas

    2013-12-01

    The objective of this study was to investigate the influence of emulsifiers, waxes, fat concentration, and processing conditions on the application of wax oleogel to replace solid fat content and create optimal fat structure in ice cream. Ice creams with 10% or 15% fat were formulated with rice bran wax (RBW), candelilla wax (CDW), or carnauba wax (CBW) oleogels, containing 10% wax and 90% high-oleic sunflower oil. The ice creams were produced using batch or continuous freezing processes. Transmission electron microscopy (TEM) and cryo-scanning electron microscopy were used to evaluate the microstructure of ice cream and the ultrastructure of oleogel droplets in ice cream mixes. Among the wax oleogels, RBW oleogel had the ability to form and sustain structure in 15% fat ice creams when glycerol monooleate (GMO) was used as the emulsifier. TEM images revealed that the high degree of fat structuring observed in GMO samples was associated with the RBW crystal morphology within the fat droplet, which was characterized by the growth of crystals at the outer edge of the droplet. Continuous freezing improved fat structuring compared to batch freezing. RBW oleogels established better structure compared to CDW or CBW oleogels. These results demonstrate that RBW oleogel has the potential to develop fat structure in ice cream in the presence of GMO and sufficiently high concentrations of oleogel.

  8. Anatomical models and wax Venuses: art masterpieces or scientific craft works?

    PubMed

    Ballestriero, R

    2010-02-01

    The art of wax modelling has an ancient origin but rose to prominence in 14th century Italy with the cult of votive artefacts. With the advent of Neoclassicism this art, now deemed repulsive, continued to survive in a scientific environment, where it flourished in the study of normal and pathological anatomy, obstetrics, zoology and botany. The achievement of having originated the creation of anatomical models in coloured wax must be ascribed to a joint effort undertaken by the Sicilian wax modeller Gaetano Giulio Zumbo and the French surgeon Guillaume Desnoues in the late 17th century. Interest in anatomical wax models spread throughout Europe during the 18th century, first in Bologna with Ercole Lelli, Giovanni Manzolini and Anna Morandi, and then in Florence with Felice Fontana and Clemente Susini. In England, the art of anatomical ceroplastics was brought to London from Florence by the sculptor Joseph Towne. Throughout the centuries many anatomical artists preferred this material due to the remarkable mimetic likeness obtained, far surpassing any other material. Independent of the material used, whether wood, wax or clay, anatomical models were always considered merely craft works confined to hospitals or faculties of medicine and have survived to this day only because of their scientific interest. Italian and English waxes are stylistically different but the remarkable results obtained by Susini and Towne, and the fact that some contemporary artists are again representing anatomical wax bodies in their works, makes the border that formerly separated art and craft indistinguishable. PMID:20002228

  9. Anatomical models and wax Venuses: art masterpieces or scientific craft works?

    PubMed Central

    Ballestriero, R

    2010-01-01

    The art of wax modelling has an ancient origin but rose to prominence in 14th century Italy with the cult of votive artefacts. With the advent of Neoclassicism this art, now deemed repulsive, continued to survive in a scientific environment, where it flourished in the study of normal and pathological anatomy, obstetrics, zoology and botany. The achievement of having originated the creation of anatomical models in coloured wax must be ascribed to a joint effort undertaken by the Sicilian wax modeller Gaetano Giulio Zumbo and the French surgeon Guillaume Desnoues in the late 17th century. Interest in anatomical wax models spread throughout Europe during the 18th century, first in Bologna with Ercole Lelli, Giovanni Manzolini and Anna Morandi, and then in Florence with Felice Fontana and Clemente Susini. In England, the art of anatomical ceroplastics was brought to London from Florence by the sculptor Joseph Towne. Throughout the centuries many anatomical artists preferred this material due to the remarkable mimetic likeness obtained, far surpassing any other material. Independent of the material used, whether wood, wax or clay, anatomical models were always considered merely craft works confined to hospitals or faculties of medicine and have survived to this day only because of their scientific interest. Italian and English waxes are stylistically different but the remarkable results obtained by Susini and Towne, and the fact that some contemporary artists are again representing anatomical wax bodies in their works, makes the border that formerly separated art and craft indistinguishable. PMID:20002228

  10. Altering small and medium alcohol selectivity in the wax ester synthase.

    PubMed

    Barney, Brett M; Ohlert, Janet M; Timler, Jacobe G; Lijewski, Amelia M

    2015-11-01

    The bifunctional wax ester synthase/acyl-coenzyme A:diacylglycerol acyltransferase (WS/DGAT or wax ester synthase) catalyzes the terminal reaction in the bacterial wax ester biosynthetic pathway, utilizing a range of alcohols and fatty acyl-CoAs to synthesize the corresponding wax ester. The wild-type wax ester synthase Maqu_0168 from Marinobacter aquaeolei VT8 exhibits a preference for longer fatty alcohols, while applications with smaller alcohols would yield products with desired biotechnological properties. Small and medium chain length alcohol substrates are much poorer substrates for the native enzyme, which may hinder broad application of the wax ester synthase in many proposed biosynthetic schemes. Developing approaches to improve enzyme activity toward specific smaller alcohol substrates first requires a clear understanding of which amino acids of the primary sequences of these enzymes contribute to substrate specificity in the native enzyme. In this report, we surveyed a range of potential residues and identified the leucine at position 356 and methionine at position 405 in Maqu_0168 as residues that affected selectivity toward small, branched, and aromatic alcohols when substituted with different amino acids. This analysis provides evidence of residues that line the binding site for wax ester synthase, which will aid rational approaches to improve this enzyme with specific substrates.

  11. Profiling candidate genes involved in wax biosynthesis in Arabidopsis thaliana by microarray analysis.

    PubMed

    Costaglioli, Patricia; Joubès, Jérôme; Garcia, Christel; Stef, Marianne; Arveiler, Benoît; Lessire, René; Garbay, Bertrand

    2005-06-01

    Plant epidermal wax forms a hydrophobic layer covering aerial plant organs which constitutes a barrier against uncontrolled water loss and biotic stresses. Wax biosynthesis requires the coordinated activity of a large number of enzymes for the formation of saturated very-long-chain fatty acids and their further transformation in several aliphatic compounds. We found in the available database 282 candidate genes that may play a role in wax synthesis, regulation and transport. To identify the most interesting candidates, we measured the level of expression of 204 genes in the aerial parts of 15-day-old Arabidopsis seedlings by performing microarray experiments. We showed that only 25% of the putative candidates were expressed to significant levels in our samples, thus significantly reducing the number of genes which will be worth studying using reverse genetics to demonstrate their involvement in wax accumulation. We identified a beta-keto acyl-CoA synthase gene, At5g43760, which is co-regulated with the wax gene CER6 in a number of conditions and organs. By contrast, we showed that neither the fatty acyl-CoA reductase genes nor the wax synthase genes were expressed in 15-day-old leaves and stems, raising questions about the identity of the enzymes involved in the acyl-reduction pathway that accounts for 20% of the total wax amount. PMID:15914083

  12. Ridge transform fault spreading pattern in freezing wax.

    PubMed

    Oldenburg, D W; Brune, J N

    1972-10-20

    A laboratory experiment shows that ridge-ridge transform faults, inactive fracture zones, and other features characteristic of spreading oceanic ridges can be produced in a variety of paraffins. Although the resultant pattern depends upon the temperature of the wax and the ratio of spreading rate to surface cooling, the characteristic orthogonal ridge transform fault system is a preferred mode of separation. Symmetric spreading occurs under conditions of no tensile strength across the ridge, and the stability of transform faults is a consequence of their lack of shear strength. The experiment also shows that properties characteristic of oceanic ridges occur under conditions of passive convection where upwelling of material at the ridge crest is a result only of hydrostatic forces in the fluid; that is, the plate separation is caused not by large convective forces beneath the ridge but rather by tensile forces in the plate. PMID:17735477

  13. Formulation of wax oxybenzone microparticles using a factorial approach.

    PubMed

    Gomaa, Y A; Darwish, I A; Boraei, N A; El-Khordagui, L K

    2010-01-01

    Oxybenzone wax microparticles (MPs) were prepared by the hydrophobic congealable disperse phase method. The formulation of oxybenzone-loaded MPs was optimized using a 2⁴ experimental design. Factorial analysis indicated that the main MP characteristics were influenced by initial drug loading, emulsification speed, emulsifier concentration and hydrophilic-lipophilic balance. MPs were spherical with 50.5–88.1 μm size range, 17.8–38.9 drug content in mg/100 mg MPs and 33.1–87.2% oxybenzone release in 1 h. A wide range of sunscreen delivery systems suitable for different formulation purposes were generated which may contribute to the advanced formulation of sunscreen products with improved performance. PMID:20681744

  14. Synchrotron radiation microdiffraction of ballistic molten wax microdrops

    SciTech Connect

    Graceffa, R.; Burghammer, M.; Davies, R. J.; Riekel, C.

    2008-08-15

    Using stroboscopic techniques, diffraction patterns of ballistic paraffin wax microdrops have been observed. The microdrops, generated by a high-temperature ink-jet system, travel through the 1 {mu}m synchrotron radiation beam with a speed of about 1.4 m/s. Diffraction patterns were recorded in flight by a charge couple device with a microchannel plate image intensifier stage, which was activated with the microdrop generation frequency of 1000 Hz during 2 {mu}s. The data show liquid microdrops with a constant temperature up to 8 mm from the ink-jet system capillary exit. The general technique could be adapted for studying fast structural processes, such as protein conformational changes in aqueous microdrops.

  15. Formulation of wax oxybenzone microparticles using a factorial approach.

    PubMed

    Gomaa, Y A; Darwish, I A; Boraei, N A; El-Khordagui, L K

    2010-01-01

    Oxybenzone wax microparticles (MPs) were prepared by the hydrophobic congealable disperse phase method. The formulation of oxybenzone-loaded MPs was optimized using a 2⁴ experimental design. Factorial analysis indicated that the main MP characteristics were influenced by initial drug loading, emulsification speed, emulsifier concentration and hydrophilic-lipophilic balance. MPs were spherical with 50.5–88.1 μm size range, 17.8–38.9 drug content in mg/100 mg MPs and 33.1–87.2% oxybenzone release in 1 h. A wide range of sunscreen delivery systems suitable for different formulation purposes were generated which may contribute to the advanced formulation of sunscreen products with improved performance.

  16. Bubble column apparatus for separating wax from catalyst slurry

    SciTech Connect

    Neathery, James K.; Davis, Burtron H.

    2004-07-13

    Novel methods and devices for production of liquid hydrocarbon products from gaseous reactants are disclosed. In one aspect, a method for separating a liquid hydrocarbon, typically a wax, from a catalyst containing slurry is provided, comprising passing the slurry through at least one downcomer extending from an overhead separation chamber and discharging into the bottom of a slurry bubble column reactor. The downcomer includes a cross-flow filtration element for separating a substantially particle-free liquid hydrocarbon for downstream processing. In another aspect, a method for promoting plug-flow movement in a recirculating slurry bubble column reactor is provided, comprising discharging the recirculating slurry into the reactor through at least one downcomer which terminates near the bottom of the reactor. Devices for accomplishing the above methods are also provided.

  17. Evidence for surfactant solubilization of plant epicuticular wax.

    PubMed

    Tamura, H; Knoche, M; Bukovac, M J

    2001-04-01

    The solubilization of isolated, reconstituted tomato (Lycopersicon esculentum Mill.) fruit and broccoli (Brassica oleracaea var. botrytis L.) leaf epicuticular waxes (ECW) by nonionic octylphenoxypolyethoxy ethanol surfactant (Triton X-100) was demonstrated in a model system by TLC and fluorescence analysis using pyrene as a fluorescent probe. ECW was solubilized at or above the surfactant critical micelle concentration; solubilization increased with an increase in micelle concentration. As shown by the fluorescence quenching of pyrene, surfactant solubilization of the ECW increased rapidly for the first 12 h, then approached a plateau, increased linearly with an increase in temperature (22--32 degrees C), and decreased linearly with the log of the polyoxyethylene chain length (range 5--40 oxyethylenes). These data are discussed in relation to surfactant effects on phytotoxicity and performance of foliar spray application of agrochemicals. PMID:11308330

  18. SERS, FT-Raman and FT-IR studies of dithiocarbamates

    NASA Astrophysics Data System (ADS)

    Mylrajan, M.

    1995-03-01

    Surface-enhanced Raman scattering (SERS) spectra of dimethyl and diehtyldithiocarbamate (DMDTC and DEDTC) ions were obtained with different wavelength excitations in citrate reduced silver sol and compared with FT-Raman and FT-IR spectra. The red wavelength excitation shows large enhancement compared to green excitation. SERS spectra were compared with normal Raman spectra in both solid and solution form and assignments were made.

  19. High-yield preparation of wax esters via lipase-catalyzed esterification using fatty acids and alcohols from crambe and camelina oils.

    PubMed

    Steinke, G; Weitkamp, P; Klein, E; Mukherjee, K D

    2001-02-01

    Fatty acids obtained from seed oils of crambe (Crambe abyssinica) and camelina (Camelina sativa) via alkaline saponification or steam splitting were esterified using lipases as biocatalysts with oleyl alcohol and the alcohols derived from crambe and camelina oils via hydrogenolysis of their methyl esters. Long-chain wax esters were thus obtained in high yields when Novozym 435 (immobilized lipase B from Candida antarctica) and papaya (Carica papaya) latex lipase were used as biocatalysts and vacuum was applied to remove the water formed. The highest conversions to wax esters were obtained with Novozym 435 (> or =95%) after 4-6 h of reaction, whereas with papaya latex lipase such a high degree of conversion was attained after 24 h. Products obtained from stoichiometric amounts of substrates were almost exclusively (>95%) composed of wax esters having compositions approaching that of jojoba (Simmondsia chinensis) oil, especially when crambe fatty acids in combination with camelina alcohols or camelina fatty acids in combination with crambe alcohols were used as substrates.

  20. Characterization and chromosomal organization of Ty1-copia retrotransposons in wax gourd.

    PubMed

    Jiang, Biao; Liu, Wenrui; Peng, Qingwu; He, Xiaoming; Xie, Dasen

    2014-11-01

    Wax gourd (2n=2x=24) is an important vegetable species in Cucurbitaceae. Because it can be stored for a very long period of time, it plays an important role in ensuring the annual supply and regulating off-season supply of the vegetables. However, the availability of genetic information about wax gourd is limited. This study aimed to identify the useful genetic information for wax gourd. The conserved domains of reverse transcriptase (RT) genes of Ty1-copia retrotransposons were isolated from the genome of wax gourd using degenerate oligonucleotide primers. A total of twenty eight RT sequences were obtained, which showed high heterogeneity with the similarity ranging from 47.5% to 94.3%. Sixteen (57.1%) of them were found to be defective, being disrupted by stop codons and/or frameshift mutations. These 28 sequences were divided into five subfamilies. The comparative phylogenetic analysis with other Cucurbitaceae species from GenBank database showed that most retrotransposons derived from the same genus tended to cluster together, although there were a few exceptions. These results indicate that both vertical transmission and horizontal transmission are the sources of Ty1-copia retrotransposons in wax gourd. Fluorescent in situ hybridization (FISH) with Ty1-copia retrotransposon sequences as probes revealed that this kind of retrotransposons had a dispersed genomic organization, physically distributed among all the chromosomes of wax gourd, with clusters in the heterochromatin regions. This is the first report of Ty1-copia retrotransposons in wax gourd, which would be helpful for our understanding about the organization and evolutions of wax gourd genome and also provide valuable information for our utilization of wax gourd retrotransposons. PMID:25108132

  1. Neonate Plutella xylostella responses to surface wax components of a resistant cabbage (Brassica oleracea)

    SciTech Connect

    Eigenbrode, S.D.; Pillai, S.K.

    1998-10-01

    Behavior of neonate Plutella xylostella was observed and quantified during the first 5 min of contact with cabbage surface waxes and surface wax components deposited as a film (60 {micro}g/cm{sup 2}) on glass. The time larvae spent biting was greater and the time walking was less on waxes extracted from the susceptible cabbage variety, Round-Up, than on an insect-resistant glossy-wax breeding line, NY 9472. The waxes of both cabbage types were characterized and some of the compounds present at higher concentrations in the glossy waxes were tested for their deterrent effects on larvae by adding them to the susceptible waxes. Adding a mixture of four n-alkane-1-ols or a mixture of {alpha}- and {beta}-amyrins to wax from susceptible cabbage reduced the number of insects biting and, among those biting, reduced the time biting and increased the time walking in a dose-dependent manner. Among individual n-alkane-1-ols, adding C{sub 24} or C{sub 25} alcohols reduced the number of insects biting but only adding C{sub 25} alcohol reduced the time spent biting among those insects that initiated biting. Adding a mixture of five n-alkanoic acids did not affect biting, but increased the time spent palpating and decreased walking time. Among individual n-alkanoic acids, only adding C{sub 14} significantly increased the time palpating. If the observed responses were gustory, the results indicate that some primary wax components, including specific long-chain alkyl components, have allelochemical activity influencing host acceptance behavior by a lepidopteran larva.

  2. Characterization and chromosomal organization of Ty1-copia retrotransposons in wax gourd.

    PubMed

    Jiang, Biao; Liu, Wenrui; Peng, Qingwu; He, Xiaoming; Xie, Dasen

    2014-11-01

    Wax gourd (2n=2x=24) is an important vegetable species in Cucurbitaceae. Because it can be stored for a very long period of time, it plays an important role in ensuring the annual supply and regulating off-season supply of the vegetables. However, the availability of genetic information about wax gourd is limited. This study aimed to identify the useful genetic information for wax gourd. The conserved domains of reverse transcriptase (RT) genes of Ty1-copia retrotransposons were isolated from the genome of wax gourd using degenerate oligonucleotide primers. A total of twenty eight RT sequences were obtained, which showed high heterogeneity with the similarity ranging from 47.5% to 94.3%. Sixteen (57.1%) of them were found to be defective, being disrupted by stop codons and/or frameshift mutations. These 28 sequences were divided into five subfamilies. The comparative phylogenetic analysis with other Cucurbitaceae species from GenBank database showed that most retrotransposons derived from the same genus tended to cluster together, although there were a few exceptions. These results indicate that both vertical transmission and horizontal transmission are the sources of Ty1-copia retrotransposons in wax gourd. Fluorescent in situ hybridization (FISH) with Ty1-copia retrotransposon sequences as probes revealed that this kind of retrotransposons had a dispersed genomic organization, physically distributed among all the chromosomes of wax gourd, with clusters in the heterochromatin regions. This is the first report of Ty1-copia retrotransposons in wax gourd, which would be helpful for our understanding about the organization and evolutions of wax gourd genome and also provide valuable information for our utilization of wax gourd retrotransposons.

  3. Detection of starch adulteration in onion powder by FT-NIR and FT-IR spectroscopy.

    PubMed

    Lohumi, Santosh; Lee, Sangdae; Lee, Wang-Hee; Kim, Moon S; Mo, Changyeun; Bae, Hanhong; Cho, Byoung-Kwan

    2014-09-24

    Adulteration of onion powder with cornstarch was identified by Fourier transform near-infrared (FT-NIR) and Fourier transform infrared (FT-IR) spectroscopy. The reflectance spectra of 180 pure and adulterated samples (1-35 wt % starch) were collected and preprocessed to generate calibration and prediction sets. A multivariate calibration model of partial least-squares regression (PLSR) was executed on the pretreated spectra to predict the presence of starch. The PLSR model predicted adulteration with an R(p)2 of 0.98 and a standard error of prediction (SEP) of 1.18% for the FT-NIR data and an R(p)2 of 0.90 and SEP of 3.12% for the FT-IR data. Thus, the FT-NIR data were of greater predictive value than the FT-IR data. Principal component analysis on the preprocessed data identified the onion powder in terms of added starch. The first three principal component loadings and β coefficients of the PLSR model revealed starch-related absorption. These methods can be applied to rapidly detect adulteration in other spices.

  4. Detection of metanil yellow contamination in turmeric using FT-Raman and FT-IR spectroscopy

    NASA Astrophysics Data System (ADS)

    Dhakal, Sagar; Chao, Kuanglin; Qin, Jianwei; Kim, Moon; Schmidt, Walter; Chan, Dian

    2016-05-01

    Turmeric is well known for its medicinal value and is often used in Asian cuisine. Economically motivated contamination of turmeric by chemicals such as metanil yellow has been repeatedly reported. Although traditional technologies can detect such contaminants in food, high operational costs and operational complexities have limited their use to the laboratory. This study used Fourier Transform Raman Spectroscopy (FT-Raman) and Fourier Transform - Infrared Spectroscopy (FT-IR) to identify metanil yellow contamination in turmeric powder. Mixtures of metanil yellow in turmeric were prepared at concentrations of 30%, 25%, 20%, 15%, 10%, 5%, 1% and 0.01% (w/w). The FT-Raman and FT-IR spectral signal of pure turmeric powder, pure metanil yellow powder and the 8 sample mixtures were obtained and analyzed independently to identify metanil yellow contamination in turmeric. The results show that FT-Raman spectroscopy and FT-IR spectroscopy can detect metanil yellow mixed with turmeric at concentrations as low as 1% and 5%, respectively, and may be useful for non-destructive detection of adulterated turmeric powder.

  5. Particulate pollutants are capable to 'degrade' epicuticular waxes and to decrease the drought tolerance of Scots pine (Pinus sylvestris L.).

    PubMed

    Burkhardt, Juergen; Pariyar, Shyam

    2014-01-01

    Air pollution causes the amorphous appearance of epicuticular waxes in conifers, usually called wax 'degradation' or 'erosion', which is often correlated with tree damage symptoms, e.g., winter desiccation. Previous investigations concentrated on wax chemistry, with little success. Here, we address the hypothesis that both 'wax degradation' and decreasing drought tolerance of trees may result from physical factors following the deposition of salt particles onto the needles. Pine seedlings were sprayed with dry aerosols or 50 mM solutions of different salts. The needles underwent humidity changes within an environmental scanning electron microscope, causing salt expansion on the surface and into the epistomatal chambers. The development of amorphous wax appearance by deliquescent salts covering tubular wax fibrils was demonstrated. The minimum epidermal conductance of the sprayed pine seedlings increased. Aerosol deposition potentially 'degrades' waxes and decreases tree drought tolerance. These effects have not been adequately considered thus far in air pollution research. PMID:23791043

  6. Soil water stress affects both cuticular wax content and cuticle-related gene expression in young saplings of maritime pine (Pinus pinaster Ait)

    PubMed Central

    2013-01-01

    Background The cuticle is a hydrophobic barrier located at the aerial surface of all terrestrial plants. Recent studies performed on model plants, such as Arabidopsis thaliana, have suggested that the cuticle may be involved in drought stress adaptation, preventing non-stomatal water loss. Although forest trees will face more intense drought stresses (in duration and intensity) with global warming, very few studies on the role of the cuticle in drought stress adaptation in these long-lived organisms have been so far reported. Results This aspect was investigated in a conifer, maritime pine (Pinus pinaster Ait.), in a factorial design with two genetic units (two half-sib families with different growth rates) and two treatments (irrigated vs non-irrigated), in field conditions. Saplings were grown in an open-sided greenhouse and half were irrigated three times per week for two growing seasons. Needles were sampled three times per year for cuticular wax (composition and content) and transcriptome (of 11 genes involved in cuticle biosynthesis) analysis. Non-irrigated saplings (i) had a higher cuticular wax content than irrigated saplings and (ii) overexpressed most of the genes studied. Both these trends were more marked in the faster growing family. Conclusions The higher cuticular wax content observed in the non-irrigated treatment associated with strong modifications in products from the decarbonylation pathway suggest that cuticular wax may be involved in drought stress adaptation in maritime pine. This study provides also a set of promising candidate genes for future forward genetic studies in conifers. PMID:23815794

  7. Identification of an Arabidopsis Fatty Alcohol:Caffeoyl-Coenzyme A Acyltransferase Required for the Synthesis of Alkyl Hydroxycinnamates in Root Waxes1[W][OA

    PubMed Central

    Kosma, Dylan K.; Molina, Isabel; Ohlrogge, John B.; Pollard, Mike

    2012-01-01

    While suberin is an insoluble heteropolymer, a number of soluble lipids can be extracted by rapid chloroform dipping of roots. These extracts include esters of saturated long-chain primary alcohols and hydroxycinnamic acids. Such fatty alcohols and hydroxycinnamic acids are also present in suberin. We demonstrate that alkyl coumarates and caffeates, which are the major components of Arabidopsis (Arabidopsis thaliana) root waxes, are present primarily in taproots. Previously we identified ALIPHATIC SUBERIN FERULOYL TRANSFERASE (At5g41040), a HXXXD-type acyltransferase (BAHD family), responsible for incorporation of ferulate into aliphatic suberin of Arabidopsis. However, aliphatic suberin feruloyl transferase mutants were unaffected in alkyl hydroxycinnamate ester root wax composition. Here we identify a closely related gene, At5g63560, responsible for the synthesis of a subset of alkyl hydroxycinnamate esters, the alkyl caffeates. Transgenic plants harboring PAt5g63560::YFP fusions showed transcriptional activity in suberized tissues. Knockout mutants of At5g63560 were severely reduced in their alkyl caffeate but not alkyl coumarate content. Recombinant At5g63560p had greater acyltransferase activity when presented with caffeoyl-Coenzyme A (CoA) substrate, thus we have named this acyltransferase FATTY ALCOHOL:CAFFEOYL-CoA CAFFEOYL TRANSFERASE. Stress experiments revealed elevated alkyl coumarate content in root waxes of NaCl-treated wild-type and fatty alcohol:caffeoyl-CoA caffeoyl transferase plants. We further demonstrate that FATTY ACYL-CoA REDUCTASEs (FARs) FAR5 (At3g44550), FAR4 (At3g44540), and FAR1 (At5g22500) are required for the synthesis of C18, C20, and C22 alkyl hydroxycinnamates, respectively. Collectively, these results suggest that multiple acyltransferases are utilized for the synthesis of alkyl hydroxycinnamate esters of Arabidopsis root waxes and that FAR1/4/5 provide the fatty alcohols required for alkyl hydroxycinnamate synthesis. PMID:22797656

  8. Identification of an Arabidopsis fatty alcohol:caffeoyl-Coenzyme A acyltransferase required for the synthesis of alkyl hydroxycinnamates in root waxes.

    PubMed

    Kosma, Dylan K; Molina, Isabel; Ohlrogge, John B; Pollard, Mike

    2012-09-01

    While suberin is an insoluble heteropolymer, a number of soluble lipids can be extracted by rapid chloroform dipping of roots. These extracts include esters of saturated long-chain primary alcohols and hydroxycinnamic acids. Such fatty alcohols and hydroxycinnamic acids are also present in suberin. We demonstrate that alkyl coumarates and caffeates, which are the major components of Arabidopsis (Arabidopsis thaliana) root waxes, are present primarily in taproots. Previously we identified ALIPHATIC SUBERIN FERULOYL TRANSFERASE (At5g41040), a HXXXD-type acyltransferase (BAHD family), responsible for incorporation of ferulate into aliphatic suberin of Arabidopsis. However, aliphatic suberin feruloyl transferase mutants were unaffected in alkyl hydroxycinnamate ester root wax composition. Here we identify a closely related gene, At5g63560, responsible for the synthesis of a subset of alkyl hydroxycinnamate esters, the alkyl caffeates. Transgenic plants harboring P(At5g63560)::YFP fusions showed transcriptional activity in suberized tissues. Knockout mutants of At5g63560 were severely reduced in their alkyl caffeate but not alkyl coumarate content. Recombinant At5g63560p had greater acyltransferase activity when presented with caffeoyl-Coenzyme A (CoA) substrate, thus we have named this acyltransferase FATTY ALCOHOL:CAFFEOYL-CoA CAFFEOYL TRANSFERASE. Stress experiments revealed elevated alkyl coumarate content in root waxes of NaCl-treated wild-type and fatty alcohol:caffeoyl-CoA caffeoyl transferase plants. We further demonstrate that FATTY ACYL-CoA REDUCTASEs (FARs) FAR5 (At3g44550), FAR4 (At3g44540), and FAR1 (At5g22500) are required for the synthesis of C18, C20, and C22 alkyl hydroxycinnamates, respectively. Collectively, these results suggest that multiple acyltransferases are utilized for the synthesis of alkyl hydroxycinnamate esters of Arabidopsis root waxes and that FAR1/4/5 provide the fatty alcohols required for alkyl hydroxycinnamate synthesis.

  9. Leaf waxes and compound-specific δD analyses in a Holocene fluvial sediment-paleosol sequence from the upper Alazani River, SE-Georgia

    NASA Astrophysics Data System (ADS)

    Bliedtner, Marcel; von Suchodoletz, Hans; Schäfer, Imke; Zech, Jana; Zielhofer, Christoph; Zech, Roland

    2016-04-01

    Leaf waxes of terrestrial plants are relatively resistant against degradation and serve as valuable biomarkers preserved in various sedimentary archives. Compound-specific D/H analyses on leaf waxes are increasingly used to reconstruct past climate and environmental conditions. Here, we present a n-alkane and compound-specific δD record from a Holocene fluvial sediment-paleosol sequence along the upper Alazani River in eastern Georgia. Generally, such records from fluvial sedimentary archives must be divided into a catchment signal recorded in the fluvial sediment layers and a local in-situ signal recorded in the intercalated paleosols. The n-alkane homologue pattern shows a clear catchment versus in-situ signal. The paleosols are dominated by n-alkanes derived from the local vegetation, mainly grasses throughout the Holocene. The fluvial sediment layers contain leaf waxes derived from the forested catchment, although with relatively high contributions from grasses between 8 and 5 ka, possibly indicating more arid conditions. Because of the well-known altitude-effect on the isotopic composition of precipitation, we had expected more depleted δD values for the fluvial sediment layers, i.e. the catchment-derived samples, and more enriched δD values for the paleosols, i.e. the low altitude, in-situ signal. This is, however, not the case, and we speculate that the altitude effect might be offset by evapo-transpirative enrichment of tree leaf water and leaf waxes. The catchment and in-situ δD records both show a minor trend to more enriched values during the Holocene, while the recent topsoil is most depleted. Interpretation of these isotope records is not straight-forward and requires disentangling the effects of changing vegetation, source signal and local climate.

  10. Tectonic microplates in a wax model of sea-floor spreading

    NASA Astrophysics Data System (ADS)

    Katz, Richard F.; Ragnarsson, Rolf; Bodenschatz, Eberhard

    2005-01-01

    Rotating, growing microplates are observed in a wax analogue model of sea-floor spreading. Wax microplates are kinematically similar to sea-floor tectonic microplates in terms of spreading rate and growth rate. Furthermore, their spiral pseudofault geometry is quantitatively consistent with Schouten's oceanic microplate model. These results suggest that Schouten's edge-driven microplate model captures the kinematics of tectonic microplate evolution on Earth. Based on the wax observations, a theory for the nucleation of overlapping spreading centres, the precursors of tectonic microplates, is developed.

  11. Gamma irradiation testing of montan wax barrier materials for in-situ waste containment

    SciTech Connect

    Soo, P.; Heiser, J.

    1996-02-01

    A scoping study was carried out to quantify the potential use of a montan wax as a barrier material for subsurface use. If it possesses resistance to chemical and structural change, it could be used in a barrier to minimize the migration of contaminants from their storage or disposal locations. Properties that were evaluated included hardness, melting point, molecular weight, and biodegradation as a function of gamma radiation dose. The main emphasis was to quantify the wax`s long-term ability to withstand radiation-induced mechanical, chemical, and microbial degradation.

  12. Struck by lightning: Lichtenberg figures on a 19th-century wax model.

    PubMed

    Wollina, Uwe; Lang, Johanna; Klemm, Eckart; Wollina, Karin; Nowak, Andreas

    2015-01-01

    Wax models in dermatology were used to a large extent until the 1930s as three-dimensional models to illustrate various pathologic conditions and in particular cutaneous signs of disease. As an example, a young woman who was struck by lightning and developed Lichtenberg figures is presented. Lichtenberg figures are a fernlike pattern on skin, characteristic of lightning. Such a wax model housed in the German Hygiene Museum Dresden, Germany, illustrates the significance of wax models and how, even today, they can play an important role in medical education. PMID:25432817

  13. Struck by lightning: Lichtenberg figures on a 19th-century wax model.

    PubMed

    Wollina, Uwe; Lang, Johanna; Klemm, Eckart; Wollina, Karin; Nowak, Andreas

    2015-01-01

    Wax models in dermatology were used to a large extent until the 1930s as three-dimensional models to illustrate various pathologic conditions and in particular cutaneous signs of disease. As an example, a young woman who was struck by lightning and developed Lichtenberg figures is presented. Lichtenberg figures are a fernlike pattern on skin, characteristic of lightning. Such a wax model housed in the German Hygiene Museum Dresden, Germany, illustrates the significance of wax models and how, even today, they can play an important role in medical education.

  14. High-definition Fourier Transform Infrared (FT-IR) spectroscopic imaging of human tissue sections towards improving pathology.

    PubMed

    Sreedhar, Hari; Varma, Vishal K; Nguyen, Peter L; Davidson, Bennett; Akkina, Sanjeev; Guzman, Grace; Setty, Suman; Kajdacsy-Balla, Andre; Walsh, Michael J

    2015-01-01

    High-definition Fourier Transform Infrared (FT-IR) spectroscopic imaging is an emerging approach to obtain detailed images that have associated biochemical information. FT-IR imaging of tissue is based on the principle that different regions of the mid-infrared are absorbed by different chemical bonds (e.g., C=O, C-H, N-H) within cells or tissue that can then be related to the presence and composition of biomolecules (e.g., lipids, DNA, glycogen, protein, collagen). In an FT-IR image, every pixel within the image comprises an entire Infrared (IR) spectrum that can give information on the biochemical status of the cells that can then be exploited for cell-type or disease-type classification. In this paper, we show: how to obtain IR images from human tissues using an FT-IR system, how to modify existing instrumentation to allow for high-definition imaging capabilities, and how to visualize FT-IR images. We then present some applications of FT-IR for pathology using the liver and kidney as examples. FT-IR imaging holds exciting applications in providing a novel route to obtain biochemical information from cells and tissue in an entirely label-free non-perturbing route towards giving new insight into biomolecular changes as part of disease processes. Additionally, this biochemical information can potentially allow for objective and automated analysis of certain aspects of disease diagnosis.

  15. 347. Caltrans, Photographer April 10, 1935 "500 FT. SPANS"; VIEW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    347. Caltrans, Photographer April 10, 1935 "500 FT. SPANS"; VIEW OF THROUGH TRUSS (500 FT. SPANS) UNDER CONSTRUCTION. 7-613 - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  16. 1. Zinc Plant, looking north, down Government Gulch. 610 ft. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Zinc Plant, looking north, down Government Gulch. 610 ft. tall stack replaced original 200 ft. radial brick stack formerly at rear of Cottrell treater. - Sullivan Electrolytic Zinc Plant, Government Gulch, Kellogg, Shoshone County, ID

  17. Purification of a jojoba embryo wax synthase, cloning of its cDNA, and production of high levels of wax in seeds of transgenic arabidopsis.

    PubMed

    Lardizabal, K D; Metz, J G; Sakamoto, T; Hutton, W C; Pollard, M R; Lassner, M W

    2000-03-01

    Wax synthase (WS, fatty acyl-coenzyme A [coA]: fatty alcohol acyltransferase) catalyzes the final step in the synthesis of linear esters (waxes) that accumulate in seeds of jojoba (Simmondsia chinensis). We have characterized and partially purified this enzyme from developing jojoba embryos. A protein whose presence correlated with WS activity during chromatographic fractionation was identified and a cDNA encoding that protein was cloned. Seed-specific expression of the cDNA in transgenic Arabidopsis conferred high levels of WS activity on developing embryos from those plants. The WS sequence has significant homology with several Arabidopsis open reading frames of unknown function. Wax production in jojoba requires, in addition to WS, a fatty acyl-CoA reductase (FAR) and an efficient fatty acid elongase system that forms the substrates preferred by the FAR. We have expressed the jojoba WS cDNA in Arabidopsis in combination with cDNAs encoding the jojoba FAR and a beta-ketoacyl-CoA synthase (a component of fatty acid elongase) from Lunaria annua. (13)C-Nuclear magnetic resonance analysis of pooled whole seeds from transgenic plants indicated that as many as 49% of the oil molecules in the seeds were waxes. Gas chromatography analysis of transmethylated oil from individual seeds suggested that wax levels may represent up to 70% (by weight) of the oil present in those seeds.

  18. MALDI MS sample preparation by using paraffin wax film: systematic study and application for peptide analysis.

    PubMed

    Wang, Junhua; Chen, Ruibing; Ma, Mingming; Li, Lingjun

    2008-01-15

    Recently developed sample preparation techniques employing hydrophobic sample support have improved the detection sensitivity and mass spectral quality of matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). These methods concentrate the samples on target by minimizing the sample area via the solvent repellent effect of the target surface. In the current study, we employed the use of paraffin wax film (Parafilm M) for improved MALDI MS analysis of low-abundance peptide mixtures, including neuronal tissue releasate and protein tryptic digests. This thin film was found to strongly repel polar solvents including water, methanol, and acetonitrile, which enabled the application of a wide range of sample preparation protocols that involved the use of various organic solvents. A "nanoliter-volume deposition" technique employing a capillary column has been used to produce tiny ( approximately 400 microm) matrix spots of 2,5-dihydroxybenzoic acid on the film. By systematically optimizing the sample volume, solvent composition, and film treatment, the Parafilm M substrate in combination with the nanoliter-volume matrix deposition method allowed dilute sample to be concentrated on the film for MALDI MS analysis. Peptide mixtures with nanomolar concentrations have been detected by MALDI time-of-flight and MALDI Fourier transform ion cyclotron resonance mass spectrometers. Overall, the use of Parafilm M enabled improved sensitivity and spectral quality for the analysis of complex peptide mixtures.

  19. Late Glacial vegetation reconstruction based on leaf waxes from the Gemündener Maar, Germany

    NASA Astrophysics Data System (ADS)

    Wüthrich, Lorenz; Lutz, Selina; Zech, Michael; Hepp, Johannes; Sirocko, Frank; Zech, Roland

    2015-04-01

    Lake sediments are valuable archives for the reconstruction of past changes in climate and vegetation. In the present study, we analyse samples from the Gemündener Maar, a lake situated in the western Eiffel, Germany, for their leaf wax composition: In the bottom part of the core, corresponding to the Oldest Dryas (i.e. older than ~15 ka), n-alkanes have a high average chain length (ACL), which points to a vegetation dominated by grass. During the Bölling/Alleröd, a decrease of the ACL can be interpreted as signal of more deciduous trees. During the Younger Dryas (~12.8 to 11.5 ka), the ACL increases again. Trees probably became again less abundant, before finally, the ACL records the return of deciduous trees during the early Holocene. In general, the total concentrations of both, n-alkanes and sugar biomarkers are high enough to measure compound-specific isotopes on n-alkanes (deuterium) and sugars (18-O). Combined, these two isotopes might help to obtain more information about the relative humidity and mean air temperature during the late glacial.

  20. Transient Response of Different Highly Conductive PCM Composites

    NASA Astrophysics Data System (ADS)

    Mahmoud Alhamdo, Mohammed H.; Bdaiwi, Bashar A.; Hasan, Ali H.

    In this work, the thermal conductivity of paraffin wax has been enhanced by employing four different high conductivity additives infiltrated within the PCM. These include the use of Graphite Powder (GP), Copper Particles (CP), Aluminum oxide Particles (AP), and Copper Network (CN). Four different types of pure waxes were selected, tested and compared. Twelve samples of wax/additives composites were prepared by adding different mass ratios of 3, 6 and 9 % of additives by weight in each type of wax. The storage system contains spherical capsules filled with composite PCMs that are packed in an insulated cylindrical storage. Transient temperature based governing equations have been developed and solved numerically by both ANSYS FLUENT 14 code and by numerical implicit time marching model. With progress of time, results showed that the numerical predictions of ANSYS software start to deviate from the experimental observations. The grade-B paraffin was found to be the best one. Results indicate that all the enhancement methods have significant effect on the thermal response of the system. However, the utilization of 6 % additives by weight has been found to provide the best enhancement effect. The developed new-sort CN composite is found to produce the best thermal response due to its good homogeneity with wax and its high conductivity. Results showed that for CN composite with 6 % additives, the charging and discharging time decreased by 26.4 and 30.3 % respectively than that of pure wax and the thermal conductivity enhanced by 2.57 times that of pure wax.