Sample records for cocoa powder

  1. Tolerance for High Flavanol Cocoa Powder in Semisweet Chocolate

    PubMed Central

    Harwood, Meriel L.; Ziegler, Gregory R.; Hayes, John E.

    2013-01-01

    Endogenous polyphenolic compounds in cacao impart both bitter and astringent characteristics to chocolate confections. While an increase in these compounds may be desirable from a health perspective, they are generally incongruent with consumer expectations. Traditionally, chocolate products undergo several processing steps (e.g., fermentation and roasting) that decrease polyphenol content, and thus bitterness. The objective of this study was to estimate group rejection thresholds for increased content of cocoa powder produced from under-fermented cocoa beans in a semisweet chocolate-type confection. The group rejection threshold was equivalent to 80.7% of the non-fat cocoa solids coming from the under-fermented cocoa powder. Contrary to expectations, there were no differences in rejection thresholds when participants were grouped based on their self-reported preference for milk or dark chocolate, indicating that these groups react similarly to an increase in high cocoa flavanol containing cocoa powder. PMID:23792967

  2. Microbiota Dynamics and Diversity at Different Stages of Industrial Processing of Cocoa Beans into Cocoa Powder

    PubMed Central

    Lima, Lídia J. R.; van der Velpen, Vera; Wolkers-Rooijackers, Judith; Kamphuis, Henri J.; Nout, M. J. Rob

    2012-01-01

    We sampled a cocoa powder production line to investigate the impact of processing on the microbial community size and diversity at different stages. Classical microbiological methods were combined with 16S rRNA gene PCR-denaturing gradient gel electrophoresis, coupled with clone library construction, to analyze the samples. Aerobic thermoresistant spores (ThrS) (100°C; 10 min) were also isolated and characterized (identity, genetic diversity, and spore heat resistance), in view of their relevance to the quality of downstream heat-treated cocoa-flavored drinks. In the nibs (broken, shelled cocoa beans), average levels of total aerobic microorganisms (TAM) (4.4 to 5.6 log CFU/g) and aerobic total spores (TS) (80°C; 10 min; 4.3 to 5.5 log CFU/g) were significantly reduced (P < 0.05) as a result of alkalizing, while fungi (4.2 to 4.4 log CFU/g) and Enterobacteriaceae (1.7 to 2.8 log CFU/g) were inactivated to levels below the detection limit, remaining undetectable throughout processing. Roasting further decreased the levels of TAM and TS, but they increased slightly during subsequent processing. Molecular characterization of bacterial communities based on enriched cocoa samples revealed a predominance of members of the Bacillaceae, Pseudomonadaceae, and Enterococcaceae. Eleven species of ThrS were found, but Bacillus licheniformis and the Bacillus subtilis complex were prominent and revealed great genetic heterogeneity. We concluded that the microbiota of cocoa powder resulted from microorganisms that could have been initially present in the nibs, as well as microorganisms that originated during processing. B. subtilis complex members, particularly B. subtilis subsp. subtilis, formed the most heat-resistant spores. Their occurrence in cocoa powder needs to be considered to ensure the stability of derived products, such as ultrahigh-temperature-treated chocolate drinks. PMID:22327588

  3. Gas chromatographic determination and mechanism of formation of D-amino acids occurring in fermented and roasted cocoa beans, cocoa powder, chocolate and cocoa shell

    Microsoft Academic Search

    R. Pätzold; H. Brückner

    2006-01-01

    Summary.  Fermented cocoa beans of various countries of origin (Ivory Coast, Ghana, Sulawesi), cocoa beans roasted under defined conditions\\u000a (100–150?°C; 30–120?min), low and high fat cocoa powder, various brands of chocolate, and cocoa shells were analyzed for their\\u000a contents of free L-and D-amino acids.\\u000a \\u000a Amino acids were isolated from defatted products using a cation exchanger and converted into volatile N(O)-pentafluoropropionyl amino

  4. Potential complementarity of high-flavanol cocoa powder and spirulina for health protection

    Microsoft Academic Search

    Mark F. McCarty; Jorge Barroso-Aranda; Francisco Contreras

    2010-01-01

    Recent studies show that ingestion of flavanol-rich cocoa powder provokes increased endothelial production of nitric oxide - an effect likely mediated by epicatchin - and thus may have considerable potential for promoting vascular health. The Kuna Indians of Panama, who regularly consume large amounts of flavanol-rich cocoa, are virtually free of hypertension and stroke, even though they salt their food.

  5. Potential complementarity of high-flavanol cocoa powder and spirulina for health protection.

    PubMed

    McCarty, Mark F; Barroso-Aranda, Jorge; Contreras, Francisco

    2010-02-01

    Recent studies show that ingestion of flavanol-rich cocoa powder provokes increased endothelial production of nitric oxide - an effect likely mediated by epicatchin - and thus may have considerable potential for promoting vascular health. The Kuna Indians of Panama, who regularly consume large amounts of flavanol-rich cocoa, are virtually free of hypertension and stroke, even though they salt their food. Of potentially complementary merit is the cyanobacterium spirulina, which has been used as a food in certain cultures. Spirulina is exceptionally rich in phycocyanobilin (PCB), which recently has been shown to act as a potent inhibitor of NADPH oxidase; this effect likely rationalizes the broad range of anti-inflammatory, cytoprotective, and anti-atherosclerotic effects which orally administered spirulina has achieved in rodent studies. In light of the central pathogenic role which NADPH oxidase-derived oxidant stress plays in a vast range of disorders, spirulina or PCB-enriched spirulina extracts may have remarkable potential for preserving and restoring health. Joint administration of flavanol-rich cocoa powder and spirulina may have particular merit, inasmuch as cocoa can mask the somewhat disagreeable flavor and odor of spirulina, whereas the antioxidant impact of spirulina could be expected to amplify the bioactivity of the nitric oxide evoked by cocoa flavanols in inflamed endothelium. Moreover, there is reason to suspect that, by optimizing cerebrovascular perfusion while quelling cerebral oxidant stress, cocoa powder and spirulina could collaborate in prevention of senile dementia. Thus, food products featuring ample amounts of both high-flavanol cocoa powder and spirulina may have considerable potential for health promotion, and merit evaluation in rodent studies and clinical trials. PMID:19577379

  6. Effects of long-term administration of a cocoa polyphenolic extract (Acticoa powder) on cognitive performances in aged rats

    Microsoft Academic Search

    Jean-François Bisson; Amine Nejdi; Pascale Rozan; Sophie Hidalgo; Robert Lalonde; Michaël Messaoudi

    2008-01-01

    Numerous studies have indicated that increased vulnerability to oxidative stress may be the main factor involved in functional declines during normal and pathological ageing, and that antioxidant agents, such as polyphenols, may improve or prevent these deficits. We examined whether 1-year administration of a cocoa polyphenolic extract (Acticoa powder), orally delivered at the dose of 24 mg\\/kg per d between

  7. Cocoa Powder Triggers Neuroprotective and Preventive Effects in a Human Alzheimer's Disease Model by Modulating BDNF Signaling Pathway

    PubMed Central

    Cimini, Annamaria; Gentile, Roberta; D'Angelo, Barbara; Benedetti, Elisabetta; Cristiano, Loredana; Avantaggiati, Maria Laura; Giordano, Antonio; Ferri, Claudio; Desideri, Giovambattista

    2014-01-01

    The molecular mechanisms linking A? to the onset of neurotoxicity are still largely unknown, but several lines of evidence point to reactive oxygen species, which are produced even under the effect of nanomolar concentrations of soluble A?-oligomers. The consequent oxidative stress is considered as the mediator of a cascade of degenerative events in many neurological disorders. Epidemiological studies indicate that dietary habits and antioxidants from diet can influence the incidence of neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In the recent years, a number of reviews have reported on neuroprotective effects of polyphenols in cell and animal models. However, the majority of these studies have focused only on the anti-oxidant properties of these compounds and less on the mechanism/s of action at cellular level. In this work we investigated the effect of cocoa polyphenolic extract on a human AD in vitro model. The results obtained, other than confirming the anti-oxidant properties of cocoa, demonstrate that cocoa polyphenols triggers neuroprotection by activating BDNF survival pathway, both on A? plaque treated cells and on A? oligomers treated cells, resulting in the counteraction of neurite dystrophy. On the light of the results obtained the use of cocoa powder as preventive agent for neurodegeneration is further supported. PMID:23554028

  8. Flavan-3-ol fraction from cocoa powder promotes mitochondrial biogenesis in skeletal muscle in mice

    PubMed Central

    2014-01-01

    Background Numerous clinical studies have reported that ingestion of chocolate has reduced risk of metabolic syndrome. In order to elucidate the mechanism, we evaluated the influence of flavan-3-ols derived from cocoa powder on energy metabolism in mice using an indirect calorimetric method. Method The mice were divided into two groups, and administered either distilled water or 50 mg/kg of flavan-3-ol fraction for 2 weeks. At the end of the experimental period, animals were sacrificed after blood pressure and the mean respiratory exchange ratio (RER) over 24 hours were measured. Results The mean respiratory exchange ratio (RER) over 24 hours was reduced significantly in the flavan-3-ols group. The mean blood pressure was significantly decreased in flavan-3-ols treatment group compared with control group. The protein level of carnitine palmitoyltransferase 2 (CPT2) was increased significantly by flavan-3-ols in skeletal muscle, but not in liver. Uncoupling protein (UCP) 1 was increased significantly in brown adipose tissue by flavan-3-ols. The mitochondria copy number in gastrocnemius and soleus muscles and brown adipose tissue were increased significantly by administration of flavan-3-ol fraction. Conclusion These results suggest that flavan-3-ols enhances lipolysis and promotes mitochondrial biogenesis. We conclude that improvement of metabolic syndrome risk factors following ingestion of chocolate may be induced, in part, by the mitochondrial biogenesis-promoting effect of flavan-3-ols. PMID:24708519

  9. Iron bioavailability of cocoa powder as determined by the Hb regeneration efficiency method

    Microsoft Academic Search

    Katsuhiko Yokoi; Aki Konomi; Miki Otagi

    2009-01-01

    Fe deficiency is a public-health problem worldwide, and effective measures for preventing Fe deficiency are needed. The aim of the present study was to determine the bioavailability of Fe in cocoa using the Hb regeneration efficiency (HRE) method. Thirty-five F344\\/N male weanling rats were fed a low-Fe diet for 4 weeks to deplete body Fe stores. Then, four groups of

  10. Use of water activity characteristics enables a simplified approach for defining the reference moisture condition for FDA cocoa powder in-house reference material.

    PubMed

    Cunningham, W C

    2013-10-01

    The Food and Drug Administration uses water activity behavior characteristics when adjusting test portion mass to correct for the moisture condition of its cocoa powder in-house reference material. The cocoa powder's moisture condition, and therefore weight, equilibrates according to the relative humidity (RH) of its surroundings. This process is predictable and defined by an isotherm. The reference values in the certificate of analysis are relative to the material's condition at 30% RH, which is assumed to be mid-range for typical laboratory settings. Since mass variations are relatively small within a 15-50% RH range, the mass may be measured immediately after removing a test portion from a storage bottle and used without correction if a standard uncertainty of 0.7% is acceptable for the mass. If greater accuracy is needed and the laboratory RH is known, a very simple and quick procedure can be used whereby the test portion is left open and exposed to the laboratory air overnight before weighing. After applying a correction, the standard uncertainty for mass measurement drops to 0.3%. PMID:23942587

  11. Quantitative analysis of N-phenylpropenoyl-L-amino acids in roasted coffee and cocoa powder by means of a stable isotope dilution assay.

    PubMed

    Stark, Timo; Justus, Helene; Hofmann, Thomas

    2006-04-19

    Since recent reports on the role of N-phenylpropenoyl-L-amino acids as powerful antioxidants and key contributors to the astringent taste of cocoa nibs, there is an increasing interest in the concentrations of these phytochemicals in plant-derived foods. A versatile analytical method for the accurate quantitative analysis of N-phenylpropenoyl-L-amino acids in plant-derived foods by means of HPLC-MS/MS and synthetic stable isotope labeled N-phenylpropenoyl-L-amino acids as internal standards was developed. By means of the developed stable isotope dilution assay (SIDA), showing recovery rates of 95-102%, 14 N-phenylpropenoyl-L-amino acids were quantified for the first time in cocoa and coffee samples. On the basis of the results of LC-MS/MS experiments as well as cochromatography with the synthetic reference compounds N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-tryptophan, N-[4'-hydroxy-(E)-cinnamoyl]-L-tryptophan, and N-[4'-hydroxy-3'-methoxy-(E)-cinnamoyl]-L-tyrosine, respectively, were detected for the first time in cocoa powder, and (-)-N-[4'-hydroxy-(E)-cinnamoyl]-L-tyrosine, (-)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-tyrosine, N-[4'-hydroxy-3'-methoxy-(E)-cinnamoyl]-L-tyrosine, (+)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-aspartic acid, (+)-N-[4'-hydroxy-(E)-cinnamoyl]-L-aspartic acid, N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-tryptophan, N-[4'-hydroxy-(E)-cinnamoyl]-L-tryptophan, and N-[4'-hydroxy-3'-methoxy-(E)-cinnamoyl]-L-tryptophan, respectively, were detected for the first time in coffee beverages. PMID:16608201

  12. 6.NS Making Hot Cocoa, Variation 1

    NSDL National Science Digital Library

    2012-05-01

    This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: One mug of hot chocolate uses $\\frac23$ cup of cocoa powder. How many mugs can Nelli make with 3 cups of cocoa powder? Solve the problem by drawing a p...

  13. A Comparative Study of Iron Bioavailability from Cocoa Supplemented with Ferric Pyrophosphate or Ferrous Fumarate in Rats

    Microsoft Academic Search

    S. Navas-Carretero; B. Sarriá; A. M. Pérez-Granados; S. Schoppen; M. Izquierdo-Pulido; M. P. Vaquero

    2007-01-01

    Background: Food iron fortification can be a good strategy to prevent iron deficiency. Iron bioavailability from cocoa powder enriched with ferric pyrophosphate encapsulated in liposomes or ferrous fumarate was assessed in rats. Methods: Three groups of rats consumed during 28 days either a control diet or two diets prepared with ferric pyrophosphate- or ferrous fumarate-enriched cocoa powder as the unique

  14. Short term effects of cocoa consumption on blood pressure.

    PubMed

    Alleyne, T; Alleyne, A; Arrindell, D; Balleram, N; Cozier, D; Haywood, R; Humphrey, C; Pran, L; Rampersad, K; Reyes, D; Bahall, S; Holder, R; Ignacio, D

    2014-08-01

    Hypertension, defined as diastolic pressure ? 90 mmHg and systolic pressure ? 140 mmHg, is a major cause of morbidity and mortality among black populations globally. Several studies have shown that prolonged consumption of cocoa or cocoa containing products leads to decreased blood pressure (BP) in hypertensives. In this study, we investigated the flavonoid content of the top selling cocoa/cocoa based products in Trinidad and Tobago and attempted to determine if consumption of cocoa had any immediate impact on blood pressure levels. The flavonoid content of three 100% cocoa powder products and four cocoa based formulas was measured using a modified Folin-Ciocalteu procedure. The brand with the highest flavonoid content, 372 gallic acid equivalents, was selected to evaluate the short-term impact of cocoa consumption on blood pressure. Thirty-six participants comprising nineteen hypertensives and seventeen persons with normal blood pressure had their blood pressure recorded on three separate days using ambulatory blood pressure monitors; the blood pressure was recorded every half hour for eight hours. On the first day, the participants received no intervention but on the second and third days, they received either the intervention (5 g cocoa in 125 ml water) or a placebo, in any order. Statistical analysis conducted using t-test statistic and a 95% confidence interval revealed that whether participants regularly took antihypertensive medication or not, a single intervention of cocoa induced decreases in both the diastolic and systolic BPs that were significant (p = 0.0001). Mean decreases of between 8 mmHg and 18 mmHg were observed. PMID:25429467

  15. Determination of aflatoxins in by-products of industrial processing of cocoa beans

    Microsoft Academic Search

    Marina V. Copetti; Beatriz T. Iamanaka; José Luiz Pereira; Daniel P. Lemes; Felipe Nakano; Marta H. Taniwaki

    2012-01-01

    This study has examined the occurrence of aflatoxins in 168 samples of different fractions obtained during the processing of cocoa in manufacturing plants (shell, nibs, mass, butter, cake and powder) using an optimised methodology for cocoa by-products. The method validation was based on selectivity, linearity, limit of detection and recovery. The method was shown to be adequate for use in

  16. Unsweetened natural cocoa has anti-asthmatic potential.

    PubMed

    Awortwe, C; Asiedu-Gyekye, I J; Nkansah, E; Adjei, S

    2014-01-01

    Unsweetened natural cocoa powder is enriched with nutraceutical abundance of anti-asthmatic compounds theobromine and theophylline. Cocoa powder, which is prepared after removal of the cocoa butter, contains about 1.9% theobromine and 0.21% caffeine. Anecdotal reports indicate that regular consumption of unsweetened natural cocoa powder (UNCP), a common practice in Ghana, West Africa, has the potential to reduce the tendency of asthmatic episodes. In the present paper we studied the effect of regular ingestion of aqueous extract of UNCP on hematological and histopathological changes that occur in ovalbumin (OVA)-sensitized guinea pigs. OVA-sensitized guinea pigs were challenged with aerosolized OVA 1 hour after ingestion of 300 mg/kg (low dose) or 600 mg/kg (high dose) of UNCP for 35 consecutive days. Histopathological and haematological changes in the OVA-sensitized guinea pigs were evaluated. Both negative and positive controls with distilled water and prednisolone, respectively, were used. OVA-sensitized guinea pigs demonstrated concentration-independent reduction in immune response to aerosolized OVA. There were no histo-architectural changes in the bronchiolar smooth muscles of the treated groups. Unsweetened natural cocoa powder has potential anti-asthmatic properties when administered orally at the doses tested. PMID:25004832

  17. Ochratoxin A in cocoa and chocolate sampled in Canada

    PubMed Central

    Turcotte, A.-M.; Scott, P.M.

    2011-01-01

    In order to determine the levels of ochratoxin A (OTA) in cocoa and cocoa products available in Canada, a previously published analytical method, with minor modifications to the extraction and immunoaffinity clean-up and inclusion of an evaporation step, was initially used (Method I). To improve the low method recoveries (46–61%), 40% methanol was then included in the aqueous sodium bicarbonate extraction solvent (pH 7.8) (Method II). Clean-up was on an Ochratest™ immunoaffinity column and OTA was determined by liquid chromatography (LC) with fluorescence detection. Recoveries of OTA from spiked cocoa powder (0.5 and 5 ng g?1) were 75–84%; while recoveries from chocolate were 93–94%. The optimized method was sensitive (limit of quantification (LOQ) = 0.07–0.08 ng g?1), accurate (recovery = 75–94%) and precise (coefficient of variation (CV) < 5%). It is applicable to cocoa and chocolate. Analysis of 32 samples of cocoa powder (16 alkalized and 16 natural) for OTA showed an incidence of 100%, with concentrations ranging from 0.25 to 7.8 ng g?1; in six samples the OTA level exceeded 2 ng g?1, the previously considered European Union limit for cocoa. The frequency of detection of OTA in 28 chocolate samples (21 dark or baking chocolate and seven milk chocolate) was also 100% with concentrations ranging from 0.05 to 1.4 ng g?1; one sample had a level higher than the previously considered European Union limit for chocolate (1 ng g?1). PMID:21623500

  18. Cocoa at the Visual Programming Challenge 1997

    Microsoft Academic Search

    Nikolaus Heger; Allen Cypher; David Canfield Smith

    1998-01-01

    Cocoa is a visual programming language for children. Cocoa attended the Visual Programming Challenge '97 for two reasons: to show that a fairly complex task could be implemented in Cocoa, and to test Cocoa's third-party extensions mechanism. The challenge was to navigate a Lego robot over an arbitrary track of Lego street tiles, and to create a map of the

  19. Methylxanthine composition and consumption patterns of cocoa and chocolate products.

    PubMed

    Shively, C A; Tarka, S M

    1984-01-01

    This chapter has compiled and evaluated the current information on the methylxanthine composition of cocoa and various chocolate foods and beverages, as well as the consumption pattern for these commodities. Although the earliest recorded reference to cacao was in 1502, it was not until 1876 that milk chocolate was invented, an event that formed the backbone of the chocolate industry today. The consumption of cocoa throughout the world has been influenced by a number of factors, and the period of peak consumption occurred during the early to mid-1960s when these factors were highly favorable. The greatest consumption of cocoa in metric tons over the past 10 yr has been in the United States, although the highest per capita consumer during this period was Switzerland. The African continent has been historically the primary producer of raw cocoa, with the Ivory Coast currently being the largest individual supplier. Limited marketing survey data is available for the consumption of methylxanthines in chocolate foods and beverages. In children and teenagers, the major dietary source of caffeine was found to be tea, followed by soft drinks and coffee, respectively. Although chocolate foods and beverages ranked the lowest of these dietary sources to provide caffeine, they do constitute the major source of dietary theobromine. Cacao is the major natural source of the xanthine base theobromine. Small amounts of caffeine are present in the bean along with trace amounts of theophylline. The methylxanthine content of beans varies with the varietal type, and is influenced by the fermentation process. Chocolate liquor is a semifinished product commonly called "baking" or "cooking" chocolate. The average theobromine and caffeine content of liquors has been reported at 1.2% and 0.21%, respectively. Cocoa powder, which is prepared after removal of the cocoa butter, contains about 1.9% theobromine and 0.21% caffeine. Chocolate beverages comprise the most widely studied category of chocolate products. Hot cocoa provides 62 mg/serving of theobromine and 4 mg/serving of caffeine when prepared from commercial instant mixes. Instant cold chocolate milk mixes supply an average of 58 mg/serving of theobromine and 5 mg/serving of caffeine. The methylxanthine content of chocolate foods has received only slight attention in the literature. The methylxanthine content of sweet chocolate ranges from 0.359 to 0.628% for theobromine and 0.017 to 0.125% for caffeine.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:6396642

  20. Seeding effects on solidification behavior of cocoa butter and dark chocolate. I. Kinetics of solidification

    Microsoft Academic Search

    Iwao Hachiya; Tetsuo Koyano; Kiyotaka Sato

    1989-01-01

    Effects of seeding of fat crystals on the crystallization kinetics of cocoa butter and dark chocolate were examined with a\\u000a rotational viscometer. The seed crystals employed were cocoa butter, 1,3-distearoyl-2-oleoylglycerol (SOS), 1,3-dibehenoyl-2-oleoylglycerol\\u000a (BOB) and 1,2,3-tristearoylglycerol (SSS). The seed powders were prepared by pulverization below —50?C, the dimensions being\\u000a in a range from 20–70 ?m. Particular attention was paid to the

  1. Cocoa, chocolate and cardiovascular disease

    PubMed Central

    Galleano, Monica; Oteiza, Patricia I.; Fraga, Cesar G.

    2009-01-01

    A significant body of evidence demonstrates that diets rich in fruit and vegetables promote health, and attenuate, or delay, the onset of various diseases, including cardiovascular disease (CVD), diabetes, certain cancers, and several other age-related degenerative disorders. The concept that moderate chocolate consumption could be part of a healthy diet has gained acceptance in the last years based on the health benefits ascribed to selected cocoa components. Specifically, cocoa as a plant and chocolate as food contain a series of chemicals that can interact with cell and tissue components providing protection against the development and amelioration of pathological conditions. The most relevant effects of cocoa and chocolate have been related to CVD. The mechanisms behind these effects are still under investigation. However the maintenance or restoration of vascular NO production and bioavailability and the antioxidant effects are the mechanisms most consistently supported by experimental data. This review will summarize the most recent research on the cardiovascular effects of cocoa flavanoles and related compounds. PMID:19701098

  2. SOMATIC EMBRYOGENESIS IN VENEZUELAN COCOA CULTIVARS

    Microsoft Academic Search

    Rosalía Velásquez Salazar; Yanet Sandrea; Carmen Betancourt; Jonás Mata; Félix García

    SUMMARY The traditional sexual and asexual methods of cocoa propagation have been widely used in Venezuela and worldwide, however, they have not been successful since plants with undesirable agronomic characteristics are produced. At present, plant regeneration via somatic embryogenesis provides an alternative method for clonally propagating cocoa. Therefore, a protocol was developed in order to use staminode, petal, anther and

  3. Potential value added products from Trinidad and Tobago cocoa

    Microsoft Academic Search

    D. A. Sukha

    This paper provides a brief overview on the range of potential value added products that can be made from cocoa and cocoa by-products both during the primary processing stage as well as with secondary processing. Value added processing of cocoa and cocoa by- products in Trinidad and Tobago could significantly increase the income generating capacity of the industry. In addition

  4. Cacao seeds are a "Super Fruit": A comparative analysis of various fruit powders and products

    PubMed Central

    2011-01-01

    Background Numerous popular media sources have developed lists of "Super Foods" and, more recently, "Super Fruits". Such distinctions often are based on the antioxidant capacity and content of naturally occurring compounds such as polyphenols within those whole fruits or juices of the fruit which may be linked to potential health benefits. Cocoa powder and chocolate are made from an extract of the seeds of the fruit of the Theobroma cacao tree. In this study, we compared cocoa powder and cocoa products to powders and juices derived from fruits commonly considered "Super Fruits". Results Various fruit powders and retail fruit products were obtained and analyzed for antioxidant capacity (ORAC (?M TE/g)), total polyphenol content (TP (mg/g)), and total flavanol content (TF (mg/g)). Among the various powders that were tested, cocoa powder was the most concentrated source of ORAC and TF. Similarly, dark chocolate was a significantly more concentrated source of ORAC and TF than the fruit juices. Conclusions Cocoa powder and dark chocolate had equivalent or significantly greater ORAC, TP, and TF values compared to the other fruit powders and juices tested, respectively. Cacao seeds thus provide nutritive value beyond that derived from their macronutrient composition and appear to meet the popular media's definition of a "Super Fruit". PMID:21299842

  5. In-Situ X-Ray Studies of Cocoa Butter Droplets Undergoing Simulated Spray Freezing

    Microsoft Academic Search

    M. Pore; H. H. Seah; J. W. H. Glover; D. J. Holmes; M. L. Johns; D. I. Wilson; G. D. Moggridge

    2009-01-01

    Spray freezing offers a novel manufacturing route to fine powders with controlled crystalline structures. Here we simulate\\u000a this process by freezing (using a cold dry air flow) suspended 2-mm diameter droplets of cocoa butter such that X-ray diffraction\\u000a observation of the droplet’s evolving crystalline structure is possible in situ. Initially the Form I polymorph is observed\\u000a in the droplets: this

  6. The effects of particle size, fermentation and roasting of cocoa nibs on supercritical fluid extraction of cocoa butter

    Microsoft Academic Search

    E. K. Asep; S. Jinap; T. J. Tan; A. R. Russly; S. Harcharan; S. A. H. Nazimah

    2008-01-01

    The effects of particle size, fermentation, roasting time and roasting temperature of cocoa nibs on cocoa butter extraction using supercritical fluid technology were studied. The effect of particle size was studied using cocoa liquor (D=0.074mm), ground cocoa nib (D=0.25–0.50mm and 1.0–1.2mm) and whole cocoa nibs at 35MPa, 60°C and flow rate of 2ml\\/min using supercritical carbon dioxide (SC-CO2). The effect

  7. Effect of liquid fat on melting point and polymorphic behavior of cocoa butter and a cocoa butter fraction

    Microsoft Academic Search

    N. V. Lovegren; M. S. Gray; R. O. Feuge

    1976-01-01

    The polymorphic behavior of cocoa butter and a high-melting fraction of cocoa butter (CBF) was investigated by differential\\u000a scanning calorimetry. The effect of liquid fat on melting point and polymorphic behavior was established for six mixtures:\\u000a 83.5% cocoa butter and 16.5% of a low-melting fraction of cocoa butter (CBF-LM), 90% cocoa butter and 10% olive oil, and four\\u000a mixtures of

  8. Inclusion of Cocoa as a Dietary Supplement Represses Expression of Inflammatory Proteins in Spinal Trigeminal Nucleus in Response to Chronic Trigeminal Nerve Stimulation

    PubMed Central

    Cady, Ryan J.; Denson, Jennifer E.; Durham, Paul L.

    2013-01-01

    Scope Central sensitization is implicated in the pathology of temporomandibular joint disorder (TMD) and other types of orofacial pain. We investigated the effects of dietary cocoa on expression of proteins involved in the development of central sensitization in the spinal trigeminal nucleus (STN) in response to inflammatory stimulation of trigeminal nerves. Methods and results Male Sprague Dawley rats were fed either a control diet or an isocaloric diet consisting of 10% cocoa powder 14 days prior to bilateral injection of complete Freund’s adjuvant (CFA) into the temporomandibular joint to promote prolonged activation of trigeminal ganglion neurons and glia. While dietary cocoa stimulated basal expression of GLAST and MKP-1 when compared to animals on a normal diet, cocoa suppressed basal calcitonin gene-related peptide levels in the STN. CFA-stimulated levels of protein kinase A, P2X3, P-p38, GFAP, and OX-42, whose elevated levels in the STN are implicated in central sensitization, were repressed to near control levels in animals on a cocoa enriched diet. Similarly, dietary cocoa repressed CFA-stimulated inflammatory cytokine expression. Conclusion Based on our findings, we speculate that cocoa enriched diets could be beneficial as a natural therapeutic option for TMD and other chronic orofacial pain conditions. PMID:23576361

  9. Determination of Flavanols and Procyanidins (DP 1-10) in Cocoa-Based Ingredients and Products by UHPLC: First Action 2013.03.

    PubMed

    Machonis, Philip R; Jones, Matthew A; Kwik-Uribe, Catherine; Dowell, Dawn

    2014-01-01

    Single-laboratory validation data were reviewed by the Expert Review Panel (ERP) of the Stakeholder Panel on Strategic Food Analytical Methods at the AOAC Mid-Year Meeting, March 12-14, 2013, in Rockville, MD. The ERP determined that the data presented met established standard method performance requirements and adopted a method for determination of flavanols and procyanidins (DP 1-10) in cocoa-based ingredients and products by ultra-HPLC as AOAC Official First Action Method 2013.03 on March 14, 2013. The flavanols and procyanidins (DP 1-10) are eluted using a binary gradient (solvents A and B) consisting of 98 + 2 (v/v) acetonitrile-glacial acetic acid (A) and 95 + 3 + 2 (v/v/v) methanol-water-glacial acetic acid (B). The mobile phase is applied to a diol stationary phase. Detection occurs using fluorescence detection. Recovery of flavanols and procyanidins (DP 1-10) from both high- and low-fat matrixes was 98.4-99.8%. Precision was determined for seven different sample types (cocoa extract, cocoa nib, natural cocoa powder, cocoa liquor, alkalized cocoa powder, dark chocolate, and milk chocolate). PMID:25902989

  10. 7 CFR 58.935 - Chocolate and cocoa.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...Agriculture 3 2013-01-01 2013-01-01 false Chocolate and cocoa. 58.935 Section 58.935 Agriculture ...Quality Specifications for Raw Materials § 58.935 Chocolate and cocoa. Such products used as flavor ingredients...

  11. 7 CFR 58.935 - Chocolate and cocoa.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...Agriculture 3 2014-01-01 2014-01-01 false Chocolate and cocoa. 58.935 Section 58.935 Agriculture ...Quality Specifications for Raw Materials § 58.935 Chocolate and cocoa. Such products used as flavor ingredients...

  12. 7 CFR 58.935 - Chocolate and cocoa.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Agriculture 3 2012-01-01 2012-01-01 false Chocolate and cocoa. 58.935 Section 58.935 Agriculture ...Quality Specifications for Raw Materials § 58.935 Chocolate and cocoa. Such products used as flavor ingredients...

  13. Cocoa phytochemicals: recent advances in molecular mechanisms on health.

    PubMed

    Kim, Jiyoung; Kim, Jaekyoon; Shim, Jaesung; Lee, Chang Yong; Lee, Ki Won; Lee, Hyong Joo

    2014-01-01

    Recent reports on cocoa are appealing in that a food commonly consumed for pure pleasure might also bring tangible benefits for human health. Cocoa consumption is correlated with reduced health risks of cardiovascular diseases, hypertension, atherosclerosis, and cancer, and the health-promoting effects of cocoa are mediated by cocoa-driven phytochemicals. Cocoa is rich in procyanidins, theobromine, (-)-epicatechin, catechins, and caffeine. Among the phytochemicals present in consumed cocoa, theobromine is most available in human plasma, followed by caffeine, (-)-epicatechin, catechin, and procyanidins. It has been reported that cocoa phytochemicals specifically modulate or interact with specific molecular targets linked to the pathogenesis of chronic human diseases, including cardiovascular diseases, cancer, neurodegenerative diseases, obesity, diabetes, and skin aging. This review summarizes comprehensive recent findings on the beneficial actions of cocoa-driven phytochemicals in molecular mechanisms of human health. PMID:24580540

  14. 7 CFR 58.935 - Chocolate and cocoa.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Agriculture 3 2011-01-01 2011-01-01 false Chocolate and cocoa. 58.935 Section 58.935 Agriculture ...Quality Specifications for Raw Materials § 58.935 Chocolate and cocoa. Such products used as flavor ingredients...

  15. Accurate determination of genetic identity for a single cacao bean, using molecular markers with a nanofluidic system, ensures cocoa authenticity and traceability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cacao (Theobroma cacao L.) is an important tropical crop since it is the source of cocoa butter and powder for the confectionery industry. Production and marketing of premium high-value fine flavored cacao provide opportunities for cacao growers, the chocolate industry and consumers. The higher far...

  16. Descriptive analysis and external preference mapping of powdered chocolate milk

    Microsoft Academic Search

    Guillermo Hough; Ricardo Sánchez

    1998-01-01

    Appearance, texture and flavor descriptors were developed for powdered chocolate milk. The influence of cocoa and gum concentrations on these descriptors was studied using stepwise multiple regression. Out of a total of 23 descriptors, four were non-significant. For the significant descriptors, the percentage variance explained ranged from 65 to 93%, with an average of 82%. Visual viscosity and oral thickness

  17. The declining cocoa economy and the Atlantic Forest of Southern Bahia, Brazil: Conservation attitudes of cocoa planters

    Microsoft Academic Search

    Keith Alger; Marcellus Caldas

    1994-01-01

    Summary The causes of the degradation of Brazilian Atlantic Forest in the south-eastern cocoa region of the State of Bahia are investigated by means of a survey on cocoa planter's forest conservation attitudes. Large land-owners were found to be responsible for most of the forest clearing that occurred in the past: cocoa prices compensated investment in the expansion of the

  18. The healing power of dogs: Cocoa's story.

    PubMed

    Cangelosi, Pamela R; Embrey, Carolyn N

    2006-01-01

    Animals bring a sense of "at homeness" and even normalcy to people who are hospitalized or live in health care facilities. Illnesses, separation from family, fear, loneliness, and even depression may be lessened for those who receive a therapy dog visit by providing a welcome change in routine and something to look forward to. Individuals are often more active and responsive during and after a visit. Just stroking and petting a dog requires the use of hands and arms, as well as the motions of stretching and turning. Dogs are also unconcerned with age or physical ability; they accept people as they are. This alone causes many to reach out and interact with dogs. Animals provide a focus for conversation and a common interest. As Cocoa's human partner can attest, a pet also makes it easier for strangers to talk. Cocoa is known by so many people at the facilities she visits that residents' family members often stop to talk with "Cocoa's mom" when they meet her in the community, asking questions about how Cocoa is doing. When Cocoa is no longer able to perform her services, many in her community will mourn. Cocoa's story, as well as the limited research literature, supports the positive physical and psychological effects of animals, but continued research on the effect of therapy animals on health outcomes is needed. As advocates for clients, nurses are in key positions to facilitate the inclusion of animals in clients' care. Although not for everyone, including those who react negatively to animals or who are allergic, pet therapy offers important possibilities for providing holistic care that extends not only to clients, but also to family members and staff, and to the pets themselves. PMID:16475440

  19. Characterization of the constituents and antioxidative activity of cocoa tea ( Camellia ptilophylla)

    Microsoft Academic Search

    Li Peng; Xiujuan Wang; Xianggang Shi; Chengren Li; Chuangxing Ye; Xiaohong Song

    2011-01-01

    Three main types of cocoa tea derived from Camellia ptilophylla, white cocoa tea (WCT), green cocoa tea (GCT) and black cocoa tea (BCT) were prepared. A comparison between cocoa tea and commonly consumed tea Biluochun cha (BLC), Longjing cha (Lj), Qimenhong cha (Qmh) and Yinghong 9# (Yh9) was studied. Levels of catechins and purine alkaloids were determined by HPLC. Total

  20. The effectiveness of somatic embryogenesis in eliminating the cocoa swollen shoot virus from infected cocoa trees

    Microsoft Academic Search

    A. K. Quainoo; A. C. Wetten; J. Allainguillaume

    2008-01-01

    Investigations were undertaken on the use of somatic embryogenesis to generate cocoa swollen shoot virus (CSSV) disease free clonal propagules from infected trees. Polymerase chain reaction (PCR) capillary electrophoresis revealed the presence of CSSV in all the callus tissues induced from the CSSV-infected Amelonado cocoa trees (T1, T2 and T4). The virus was transmitted to primary somatic embryos induced from

  1. Deleterious effects of maternal ingestion of cocoa upon fetal ductus arteriosus in late pregnancy

    PubMed Central

    Zielinsky, Paulo; Martignoni, Felipe V.; Vian, Izabele

    2014-01-01

    Cocoa powder has twice more antioxidants than red wine and three times more than green tea. Ten percent of its weight is made up of flavonoids. Cocoa has antioxidant and anti-inflammatory effects by downregulating cyclooxigenase-2 receptors expression in the endothelium and enhancing nitric oxide bioavailability. There are evidences that while polyphenols ingestion have cardioprotective effects in the adult, it may have deleterious effect on the fetus if ingested by the mother on the third trimester of pregnancy, causing intrauterine fetal ductus arteriosus (DA) constriction. Polyphenols present in many foods and their anti-inflammatory and antinociceptive activities have been shown to be as or more powerful than those of indomethacin. These effects are dependent on the inhibition of modulation of the arachidonic acid and the synthesis of prostaglandins, especially E-2, which is responsible for fetal DA patency. So, we hypothesized that this same mechanism is responsible for the harmful effect of polyphenol-rich foods, such as cocoa, upon the fetal DA after maternal intake of such substances in the third trimester of pregnancy, thereby rising the perspective of a note of caution for pregnant women diet. PMID:25566077

  2. The determination of cocoa butter equivalents in chocolate

    Microsoft Academic Search

    F. B. Padley; R. E. Timms

    1980-01-01

    A method of determining cocoa butter equivalents in chocolate and cocoa butter is described. The method relies on a new approach\\u000a for interpreting data obtained by triglyceride gas liquid chromatography (GLC). This technique provides information on the\\u000a composition of a fat according to the carbon number of the triglycerides (Cn). Examination of the data for a wide range of cocoa

  3. Rapid MS method for analysis of cocoa butter TAG

    Microsoft Academic Search

    J.-P. Kurvinen; O. Sjövall; R. Tahvonen; E. Anklam; H. Kallio

    2002-01-01

    Ammonia negative ion CI-MS was applied to analyze the M.W. distribution and regioisomeric structure of TAG in cocoa butter\\u000a and in cocoa butter equivalents. The M.W. distribution results obtained for a reference cocoa butter were consistent with\\u000a corresponding results obtained in an intercomparison study by chromatographic methods. Minor but statistically significant\\u000a differences were observed when proportions of the three major

  4. Cocoa and heart health: a historical review of the science.

    PubMed

    Pucciarelli, Deanna L

    2013-10-01

    The medicinal use of cocoa has a long history dating back almost five hundred years when Hernán Cortés's first experienced the drink in Mesoamerica. Doctors in Europe recommended the beverage to patients in the 1700s, and later American physicians followed suit and prescribed the drink in early America--ca. 1800s. This article delineates the historic trajectory of cocoa consumption, the linkage between cocoa's bioactive-mechanistic properties, paying special attention to nitric oxides role in vasodilation of the arteries, to the current indicators purporting the benefits of cocoa and cardiovascular health. PMID:24077240

  5. Cocoa Polyphenols and Inflammatory Markers of Cardiovascular Disease

    PubMed Central

    Khan, Nasiruddin; Khymenets, Olha; Urpí-Sardà, Mireia; Tulipani, Sara; Garcia-Aloy, Mar; Monagas, María; Mora-Cubillos, Ximena; Llorach, Rafael; Andres-Lacueva, Cristina

    2014-01-01

    Epidemiological studies have demonstrated the beneficial effect of plant-derived food intake in reducing the risk of cardiovascular disease (CVD). The potential bioactivity of cocoa and its polyphenolic components in modulating cardiovascular health is now being studied worldwide and continues to grow at a rapid pace. In fact, the high polyphenol content of cocoa is of particular interest from the nutritional and pharmacological viewpoints. Cocoa polyphenols are shown to possess a range of cardiovascular-protective properties, and can play a meaningful role through modulating different inflammatory markers involved in atherosclerosis. Accumulated evidence on related anti-inflammatory effects of cocoa polyphenols is summarized in the present review. PMID:24566441

  6. Theobromine and the pharmacology of cocoa.

    PubMed

    Smit, Hendrik Jan

    2011-01-01

    The effects of theobromine in man are underresearched, possibly owing to the assumption that it is behaviourally inert. Toxicology research in animals may appear to provide alarming results, but these cannot be extrapolated to humans for a number of reasons. Domestic animals and animals used for racing competitions need to be guarded from chocolate and cocoa-containing foods, including foods containing cocoa husks. Research ought to include caffeine as a comparative agent, and underlying mechanisms need to be further explored. Of all constituents proposed to play a role in our liking for chocolate, caffeine is the most convincing, though a role for theobromine cannot be ruled out. Most other substances are unlikely to exude a psychopharmacological effect owing to extremely low concentrations or the inability to reach the blood-brain barrier, whilst chocolate craving and addiction need to be explained by means of a culturally determined ambivalence towards chocolate. PMID:20859797

  7. Analysis of Cocoa Proanthocyanidins Using Reversed Phase High-Performance Liquid Chromatography and Electrochemical Detection: Application to Studies on the Effect of Alkaline Processing.

    PubMed

    Stanley, Todd H; Smithson, Andrew T; Neilson, Andrew P; Anantheswaran, Ramaswamy C; Lambert, Joshua D

    2015-07-01

    Flavan-3-ols and proanthocyanidins play a key role in the health beneficial effects of cocoa. Here, we developed a new reversed phased high-performance liquid chromatography-electrochemical detection (HPLC-ECD) method for the analysis of flavan-3-ols and proanthocyanidins of degree of polymerization (DP) 2-7. We used this method to examine the effect of alkalization on polyphenol composition of cocoa powder. Treatment of cocoa powder with NaOH (final pH 8.0) at 92 °C for up to 1 h increased catechin content by 40%, but reduced epicatechin and proanthocyanidins by 23-66%. Proanthocyanidin loss could be modeled using a two-phase exponential decay model (R(2) > 0.7 for epicatchin and proanthocyanidins of odd DP). Alkalization resulted in a significant color change and 20% loss of total polyphenols. The present work demonstrates the first use of HPLC-ECD for the detection of proanthocyanidins up to DP 7 and provides an initial predictive model for the effect of alkali treatment on cocoa polyphenols. PMID:26042917

  8. Cocoa and chocolate flavonoids: Implications for cardiovascular health

    Microsoft Academic Search

    Francene M Steinberg; Monica M Bearden; Carl L Keen

    2003-01-01

    This paper offers a review of current scientific research regarding the potential cardiovascular health benefits of flavonoids found in cocoa and chocolate. Recent reports indicate that the main flavonoids found in cocoa, flavan-3-ols and their oligomeric derivatives, procyanidins, have a variety of beneficial actions, including antioxidant protection and modulation of vascular homeostasis. These findings are supported by similar research on

  9. Cocoa Flavanols, Cerebral Blood Flow, Cognition, and Health: Going Forward

    E-print Network

    Pennsylvania, University of

    of CBF using arterial blood water as an endogenous contrast agent. With excellent reproducibility overCocoa Flavanols, Cerebral Blood Flow, Cognition, and Health: Going Forward David F. Dinges, PhD The articles in the issue provide important evidence for the acute effects of cocoa flavanols on the peripheral

  10. Forging New Cocoa Keys: The Impact of Unlocking the Cocoa Bean’s Genome on Pre-harvest Food Safety

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forging New Cocoa Keys: The Impact of Unlocking the Cocoa Bean’s Genome on Pre-harvest Food Safety David N. Kuhn, USDA ARS SHRS, Miami FL Sometimes it's hard to see the value and application of genomics to real world problems. How will sequencing the cacao genome affect West African farmers? Thi...

  11. The neuroprotective effects of cocoa flavanol and its influence on cognitive performance

    PubMed Central

    Nehlig, Astrid

    2013-01-01

    Cocoa powder and chocolate contain numerous substances among which there is a quite large percentage of antioxidant molecules, mainly flavonoids, most abundantly found in the form of epicatechin. These substances display several beneficial actions on the brain. They enter the brain and induce widespread stimulation of brain perfusion. They also provoke angiogenesis, neurogenesis and changes in neuron morphology, mainly in regions involved in learning and memory. Epicatechin improves various aspects of cognition in animals and humans. Chocolate also induces positive effects on mood and is often consumed under emotional stress. In addition, flavonoids preserve cognitive abilities during ageing in rats, lower the risk for developing Alzheimer's disease and decrease the risk of stroke in humans. In addition to their beneficial effects on the vascular system and on cerebral blood flow, flavonoids interact with signalization cascades involving protein and lipid kinases that lead to the inhibition of neuronal death by apoptosis induced by neurotoxicants such as oxygen radicals, and promote neuronal survival and synaptic plasticity. The present review intends to review the data available on the effects of cocoa and chocolate on brain health and cognitive abilities. PMID:22775434

  12. The effectiveness of somatic embryogenesis in eliminating the cocoa swollen shoot virus from infected cocoa trees.

    PubMed

    Quainoo, A K; Wetten, A C; Allainguillaume, J

    2008-04-01

    Investigations were undertaken on the use of somatic embryogenesis to generate cocoa swollen shoot virus (CSSV) disease free clonal propagules from infected trees. Polymerase chain reaction (PCR) capillary electrophoresis revealed the presence of CSSV in all the callus tissues induced from the CSSV-infected Amelonado cocoa trees (T1, T2 and T4). The virus was transmitted to primary somatic embryos induced from the infected callus tissues at the rate of 10 (19%), 18 (14%) and 16 (15%) for T1, T2 and T4, respectively. Virus free primary somatic embryos from the infected callus tissues converted into plantlets tested CSSV negative by PCR/capillary electrophoresis 2 years after weaning. Secondary somatic embryos induced from the CSSV-infected primary somatic embryos revealed the presence of viral fragments at the rate of 4 (4%) and 9 (9%) for T2 and T4, respectively. Real-time PCR revealed 23 of the 24 secondary somatic embryos contained no detectable virus. Based on these findings, it is proposed that progressive elimination of the CSSV in infected cocoa trees occurred from primary embryogenesis to secondary embryogenesis. PMID:18294704

  13. Proc. 2nd COCOA 2008 Parameterized Complexity of Candidate Control

    E-print Network

    Niedermeier, Rolf

    is an ordered preference list containing all candi- dates. To control an election, an external agent. 2nd COCOA 2008 work, we focus on candidate control, that is, either deleting or adding candi- dates

  14. Ecological, economic and social perspectives on cocoa production worldwide

    Microsoft Academic Search

    Margaret Franzen; Monique Borgerhoff Mulder

    2007-01-01

    Cocoa is a crop grown largely by smallholder farmers in the lowland tropics, including parts of Latin America, West Africa,\\u000a and Indonesia. Research suggests that it has the potential to provide biodiversity benefits when grown under certain shade\\u000a conditions, especially when compared with alternative land uses. The primary literature on cocoa production reveals a range\\u000a of objectives for improvement of

  15. Nutrient and antinutrient profiles of raw and fermented cocoa beans

    Microsoft Academic Search

    C. Y. Aremu; M. A. Agiang; J. O. I. Ayatse

    1995-01-01

    Freshly harvested cocoa bean was subjected to natural fermentation for 3, 6, 9 or 12 days. The proximate, mineral, hydrocyanate (HCN), oxalate and theobromine levels in the products were determined and compared with those of raw (unfermented) cocoa. The latter sample had the following composition: protein (N×6.25), 17.5; lipid, 62.9; ash, 4.4; fibre, 5.9; and nitrogen-free extract (NFE), 9.3% dry

  16. Cocoa polyphenols and inflammatory mediators1-4

    Microsoft Academic Search

    Helmut Sies; Tankred Schewe; Christian Heiss; Malte Kelm

    Cocoa products are sources of flavan-3-ols, which have attracted interestregardingcardiovascularhealth.Thisreviewprovidesasur- vey of our research on the effects of cocoa polyphenols on leukotri- ene and nitric oxide (NO) metabolism and on myeloperoxidase- induced modification of LDL. Because intake of flavonoid-rich chocolate by human subjects was reported to decrease the plasma concentrations of proinflammatory cysteinyl leukotrienes, we as- sessedwhethercocoapolyphenolsinhibitedhuman5-lipoxygenase, the key enzyme

  17. Mystery Powders

    NSDL National Science Digital Library

    American Chemical Society

    2000-01-01

    In this activity on page 2 of the PDF, learners conduct chemical tests on certain powders used in cooking. After completing the tests, learners try to figure out the identity of a mystery powder. Learners record their observations on a chart. Note: you will need an adult helper for this activity.

  18. Impact of fermentation, drying, roasting, and Dutch processing on epicatechin and catechin content of cacao beans and cocoa ingredients.

    PubMed

    Payne, Mark J; Hurst, W Jeffrey; Miller, Kenneth B; Rank, Craig; Stuart, David A

    2010-10-13

    Low molecular weight flavan-3-ols are thought to be responsible, in part, for the cardiovascular benefits associated with cocoa powder and dark chocolate. The levels of epicatechin and catechin were determined in raw and conventionally fermented cacao beans and during conventional processing, which included drying, roasting, and Dutch (alkali) processing. Unripe cacao beans had 29% higher levels of epicatechin and the same level of catechin compared to fully ripe beans. Drying had minimal effect on the epicatechin and catechin levels. Substantial decreases (>80%) in catechin and epicatechin levels were observed in fermented versus unfermented beans. When both Ivory Coast and Papua New Guinea beans were subjected to roasting under controlled conditions, there was a distinct loss of epicatechin when bean temperatures exceeded 70 °C. When cacao beans were roasted to 120 °C, the catechin level in beans increased by 696% in unfermented beans, by 650% in Ivory Coast beans, and by 640% in Papua New Guinea fermented beans compared to the same unroasted beans. These results suggest that roasting in excess of 70 °C generates significant amounts of (-)-catechin, probably due to epimerization of (-)-epicatechin. Compared to natural cocoa powders, Dutch processing caused a loss in both epicatechin (up to 98%) and catechin (up to 80%). The epicatechin/catechin ratio is proposed as a useful and sensitive indicator for the processing history of cacao beans. PMID:20843086

  19. Detailed Analysis of the Microbial Population in Malaysian Spontaneous Cocoa Pulp Fermentations

    E-print Network

    Detailed Analysis of the Microbial Population in Malaysian Spontaneous Cocoa Pulp Fermentations), Leuven, Belgium, 3 Barry Callebaut AG, Zurich, Switzerland Abstract The fermentation of cocoa pulp is one involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production

  20. Review of cocoa butter and alternative fats for use in chocolate—Part A. Compositional data

    Microsoft Academic Search

    M. Lipp; E. Anklam

    1998-01-01

    This work reviews the literature on the compositional data of vegetable fats used or proposed as alternatives to cocoa butter in chocolate and confectionery products. Cocoa butter is the only continuous phase in chocolate, thus responsible for the dispersion of all other constituents and for the physical behaviour of chocolate. Unique to cocoa butter is its brittleness at room temperature

  1. Study on distribution of mycotoxins in cocoa beans.

    PubMed

    Raters, M; Matissek, R

    2005-09-01

    Mycotoxins are not homogeneously distributed in foods which come in naturally small units, such as pistachios and peanuts, and may instead be extremely inhomogeneously distributed due to the occurrence of so-called hot spots. Tests conducted on pistachios, for example, show that a mouldy kernel can be so strongly contaminated with mycotoxins that it has a significant impact on the contamination profile of several thousand kernels. This makes a representative sampling of such foodstuffs very important but also a very difficult task. Whether cocoa beans also have a tendency to form so-called mycotoxin hot spots is hitherto unknown.A miniaturised analysis method was used in tests made on several independent batches of cocoa beans and although these tests showed that the mycotoxins ochratoxin A and the aflatoxins are not homogeneously distributed in cocoa, the tested batches revealed no real hot spots. PMID:23605337

  2. The effect of lactic acid bacteria on cocoa bean fermentation.

    PubMed

    Ho, Van Thi Thuy; Zhao, Jian; Fleet, Graham

    2015-07-16

    Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of cocoa pulp by microorganisms is crucial for developing chocolate flavor precursors. Yeasts conduct an alcoholic fermentation within the bean pulp that is essential for the production of good quality beans, giving typical chocolate characters. However, the roles of bacteria such as lactic acid bacteria and acetic acid bacteria in contributing to the quality of cocoa bean and chocolate are not fully understood. Using controlled laboratory fermentations, this study investigated the contribution of lactic acid bacteria to cocoa bean fermentation. Cocoa beans were fermented under conditions where the growth of lactic acid bacteria was restricted by the use of nisin and lysozyme. The resultant microbial ecology, chemistry and chocolate quality of beans from these fermentations were compared with those of indigenous (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii, Kluyveromyces marxianus and Saccharomyces cerevisiae, the lactic acid bacteria Lactobacillus plantarum, Lactobacillus pentosus and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in control fermentations. In fermentations with the presence of nisin and lysozyme, the same species of yeasts and acetic acid bacteria grew but the growth of lactic acid bacteria was prevented or restricted. These beans underwent characteristic alcoholic fermentation where the utilization of sugars and the production of ethanol, organic acids and volatile compounds in the bean pulp and nibs were similar for beans fermented in the presence of lactic acid bacteria. Lactic acid was produced during both fermentations but more so when lactic acid bacteria grew. Beans fermented in the presence or absence of lactic acid bacteria were fully fermented, had similar shell weights and gave acceptable chocolates with no differences in sensory rankings. It was concluded that lactic acid bacteria may not be necessary for successful cocoa fermentation. PMID:25889523

  3. Cocoa Polyphenols and Their Potential Benefits for Human Health

    PubMed Central

    Andújar, I.; Recio, M. C.; Giner, R. M.; Ríos, J. L.

    2012-01-01

    This paper compiles the beneficial effects of cocoa polyphenols on human health, especially with regard to cardiovascular and inflammatory diseases, metabolic disorders, and cancer prevention. Their antioxidant properties may be responsible for many of their pharmacological effects, including the inhibition of lipid peroxidation and the protection of LDL-cholesterol against oxidation, and increase resistance to oxidative stress. The phenolics from cocoa also modify the glycemic response and the lipid profile, decreasing platelet function and inflammation along with diastolic and systolic arterial pressures, which, taken together, may reduce the risk of cardiovascular mortality. Cocoa polyphenols can also modulate intestinal inflammation through the reduction of neutrophil infiltration and expression of different transcription factors, which leads to decreases in the production of proinflammatory enzymes and cytokines. The phenolics from cocoa may thus protect against diseases in which oxidative stress is implicated as a causal or contributing factor, such as cancer. They also have antiproliferative, antimutagenic, and chemoprotective effects, in addition to their anticariogenic effects. PMID:23150750

  4. Development of kairomone based control programs for cocoa pod borer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Cocoa Pod Borer moth presents a unique opportunity to develop host volatile attractants for control strategies for the following reasons. First, knowing what volatiles are critical for host finding by females will allow for development of mass trapping and/or attract and kill strategies to cont...

  5. Price efficiency and speculative trading in cocoa futures markets

    Microsoft Academic Search

    Michele Nardella

    2007-01-01

    In recent years a number of market participants called into question the efficiency of the price discovery mechanism in commodity futures markets. They believe that speculators move commodity futures markets away from their fundamentals by distorting prices and exacerbating volatility. The smoking gun of these allegations is the empirical observation that speculative buying (selling) precedes movements in the cocoa futures

  6. [Design of an HACCP program for a cocoa processing facility].

    PubMed

    López D'Sola, Patrizia; Sandia, María Gabriela; Bou Rached, Lizet; Hernández Serrano, Pilar

    2012-12-01

    The HACCP plan is a food safety management tool used to control physical, chemical and biological hazards associated to food processing through all the processing chain. The aim of this work is to design a HACCP Plan for a Venezuelan cocoa processing facility.The production of safe food products requires that the HACCP system be built upon a solid foundation of prerequisite programs such as Good Manufacturing Practices (GMP) and Sanitation Standard Operating Procedures (SSOP). The existence and effectiveness of these prerequisite programs were previously assessed.Good Agriculture Practices (GAP) audit to cocoa nibs suppliers were performed. To develop the HACCP plan, the five preliminary tasks and the seven HACCP principles were accomplished according to Codex Alimentarius procedures. Three Critical Control Points (CCP) were identified using a decision tree: winnowing (control of ochratoxin A), roasting (Salmonella control) and metallic particles detection. For each CCP, Critical limits were established, the Monitoring procedures, Corrective actions, Procedures for Verification and Documentation concerning all procedures and records appropriate to these principles and their application was established. To implement and maintain a HACCP plan for this processing plant is suggested. Recently OchratoxinA (OTA) has been related to cocoa beans. Although the shell separation from the nib has been reported as an effective measure to control this chemical hazard, ochratoxin prevalence study in cocoa beans produced in the country is recommended, and validate the winnowing step as well PMID:24020255

  7. Characterization of cocoa butter and cocoa butter equivalents by bulk and molecular carbon isotope analyses: implications for vegetable fat quantification in chocolate.

    PubMed

    Spangenberg, J E; Dionisi, F

    2001-09-01

    The fatty acids from cocoa butters of different origins, varieties, and suppliers and a number of cocoa butter equivalents (Illexao 30-61, Illexao 30-71, Illexao 30-96, Choclin, Coberine, Chocosine-Illipé, Chocosine-Shea, Shokao, Akomax, Akonord, and Ertina) were investigated by bulk stable carbon isotope analysis and compound specific isotope analysis. The interpretation is based on principal component analysis combining the fatty acid concentrations and the bulk and molecular isotopic data. The scatterplot of the two first principal components allowed detection of the addition of vegetable fats to cocoa butters. Enrichment in heavy carbon isotope ((13)C) of the bulk cocoa butter and of the individual fatty acids is related to mixing with other vegetable fats and possibly to thermally or oxidatively induced degradation during processing (e.g., drying and roasting of the cocoa beans or deodorization of the pressed fat) or storage. The feasibility of the analytical approach for authenticity assessment is discussed. PMID:11559122

  8. Bioactive and Sensory Properties of Herbal Spirit Enriched with Cocoa ( Theobroma cacao L.) Polyphenolics

    Microsoft Academic Search

    Draženka Komes; Ana Belš?ak-Cvitanovi?; Dunja Horži?; Helena Drmi?; Svjetlana Škrabal; Borislav Mili?evi?

    In the Southeast European and Mediterranean regions, consumption of various alcoholic beverages in the form of plain and aromatized\\u000a spirits and liqueurs is an important part of traditional local gastronomy. Especially herbal spirits and liquors are widely\\u000a spread and consumed. The objective of this study was to evaluate the potential of using cocoa raw materials (cocoa beans,\\u000a cocoa nibs or

  9. Production of cocoa butter-like fat from interesterification of vegetable oils

    Microsoft Academic Search

    M.-K. Chang; G. Abraham; V. T. John

    1990-01-01

    Cocoa butter-like fat was prepared from completely hydrogenated cottonseed and olive oils by enzymatic interesterification.\\u000a The optimum reaction time to produce the major-component of cocoa butter, 1(3)-palmitoyl-3(1)-stearoyl-2-monoolein (POS),\\u000a was 4 hr. The cocoa butter-like fat was isolated from the reaction mixture by two filtration steps. The yield of cocoa butter-like\\u000a fat was 19%, based on the weight of the original

  10. Chocolate/cocoa and human health: a review.

    PubMed

    Latif, R

    2013-03-01

    Chocolate/cocoa has been known for its good taste and proposed health effects for centuries. Earlier, chocolate used to be criticised for its fat content and its consumption was a sin rather than a remedy, associated with acne, caries, obesity, high blood pressure, coronary artery disease and diabetes. Therefore, many physicians tended to warn patients about the potential health hazards of consuming large amounts of chocolate. However, the recent discovery of biologically active phenolic compounds in cocoa has changed this perception and stimulated research on its effects in ageing, oxidative stress, blood pressure regulation, and atherosclerosis. Today, chocolate is lauded for its tremendous antioxidant potential. However, in many studies, contradictory results and concerns about methodological issues have made it hard for health professionals and the public to understand the available evidence on chocolate's effects on health. The purpose of this review is to interpret research done in the last decade on the benefits and risks of chocolate consumption. PMID:23462053

  11. Thermal and compositional properties of cocoa butter during static crystallization

    Microsoft Academic Search

    Paul S. Dimick; Douglas M. Manning

    1987-01-01

    Studies were conducted using differential scanning calorimetry (DSC) and high performance liquid chromatography (HPLC) to\\u000a determine the thermal properties and glyceride composition of cocoa butter crystals formed under static conditions. In addition\\u000a to these studies, visual characterization of the crystallites was obtained with polarized light microscopy (PLM). Crystals\\u000a were formed under controlled static or motionless conditions at formation temperatures of

  12. Mycobiota and mycotoxin producing fungi from cocoa beans.

    PubMed

    Sánchez-Hervás, M; Gil, J V; Bisbal, F; Ramón, D; Martínez-Culebras, P V

    2008-07-31

    The present study reports on the natural mycobiota occurring in cocoa beans, paying special attention to the incidence of fungal species that are potential producers of mycotoxins. The results show that predominant fungi were different species of the genus Aspergillus belonging to section Flavi and Nigri. Of the 214 strains of Aspergillus section Flavi collected from cocoa beans, 120 were identified as A. flavus and 94 as A. tamarii. Of Aspergillus section Nigri 138 strains were isolated, with 132 belonging to A. niger aggregate and 6 to A. carbonarius species. Potential ability to produce aflatoxins (AFs) B1, B2, G1 and G2, cyclopiazonic acid (CPA) and ochratoxin A (OTA) was studied by isolate culture followed by HPLC analysis of these mycotoxins in the culture extracts. Results indicated that 64.1% and 34.2% of the A. flavus strains produced AFs and CPA, respectively. Most of the A. flavus strains presented moderate toxigenicity with mean levels of AFs ranging from 100 ng g(-1) to 1000 ng g(-1). All the CPA-producing strains of A. flavus were highly toxigenic producing >30 microg g(-1) of CPA. Furthermore, 98% of A. tamarii strains produced CPA and over 50% of them were highly CPA toxigenic. With respect to OTA-producing fungi, a high percentage of black aspergilli strains (49.2%) were able to produce OTA. Additionally, most of the OTA-producing isolates were of moderate toxigenicity, producing amounts of OTA from 10 microg g(-1) to 100 microg g(-1). These results indicate that there is a possible risk factor posed by AFs, CPA and OTA contamination of cocoa beans, and consequently, cocoa products. PMID:18539350

  13. Histology of somatic embryogenesis from floral tissues cocoa

    Microsoft Academic Search

    L. Alemanno; M. Berthouly; N. Michaux-Ferrière

    1996-01-01

    Somatic embryogenesis fromTheobroma cacao L. flower buds, as previously reported on five Forastero hybrid genotypes, was tested on several other genotypes, belonging to the three cocoa-tree groups: Forastero, Trinitario and Criollo. The results gave evidence of genotypic efficiencies. Explants were cultivated under two successive conditions: callogenesis and expression media. The morphological and histological responses were different for embryogenic or non-embryogenic

  14. Somatic embryogenesis from flower explants of cocoa (Theobroma cacao L.).

    PubMed

    Silva, J J; Debergh, P

    2001-01-01

    Two types of flower explants, staminoides and petals, were used for in vitro induction of somatic embryos in cocoa. After 14 days in culture, we observed globular structures and callus formation on both types of explants. However, the better results were obtained on staminoides: 98.3% formed callus and 86.2% somatic embryos on Murashige and Skoog (1962) medium supplemented with sucrose, coconut water, 2,4-D, kinetin and agar. PMID:15952427

  15. Occurrence of aflatoxins in oilseeds providing cocoa-butter substitutes.

    PubMed

    Kershaw, S J

    1982-05-01

    Four oilseeds providing cocoa-butter substitutes--shea, pentadecima, illipe, and salseed--when tested as substrates for aflatoxin production by two strains of Aspergillus parasiticus, gave varying levels of aflatoxin. Aflatoxins were found at low levels occurring naturally in moldy shea-nuts, but none of 21 commercial shea-nut samples contained greater than 20 micrograms of aflatoxin B1 per kg. PMID:6808919

  16. Filamentous fungi producing ochratoxin a during cocoa processing in Cameroon.

    PubMed

    Mounjouenpou, Pauline; Gueule, Dominique; Fontana-Tachon, Angélique; Guyot, Bernard; Tondje, Pierre Roger; Guiraud, Joseph-Pierre

    2008-01-31

    Ochratoxin A (OTA) is the main mycotoxin occurring in cocoa. A study was conducted in Cameroon to assess how filamentous fungi and toxigenesis were affected by the type of cocoa post-harvest treatment (boxes or heaps). The filamentous fungi isolated were almost identical when fermentation was carried out in boxes or heaps, with the presence of abundant black Aspergillus filamentous fungi: A. niger and A. carbonarius. Filamentous fungi were more abundant at the end of the harvesting season. Factors affecting bean integrity (poor handling, deferred processing) resulted in a qualitative and quantitative increase in contamination, when the total number of filamentous fungi could reach a maximum value of 5.5+/-1.4x10(7) CFU g(-1) and black Aspergilli a maximum value of 1.42+/-2.2x10(7) CFU g(-1). A toxigenesis study showed that Aspergillus carbonarius was the main OTA-producing strain isolated. Its maximum production could reach 2.77 microg g(-1) on rice medium. Aspergillus niger strains did not always produce OTA and their toxigenesis was much lower. Fermented dried cocoa from poor quality pods was the most contaminated by OTA: up to 48 ng g(-1). PMID:18068845

  17. Use of biogenerated atmospheres of stored commodities for quality preservation and insect control, with particular reference to cocoa beans

    Microsoft Academic Search

    Shlomo Navarro; Tom deBruin; Aurora Ruth Montemayor; Simcha Finkelman; Miriam Rindner; Refael Dias

    Preliminary data for insect control and for quality preservation of stored cocoa beans is presented, as a methyl bromide alternative, by employing a novel approach through the use of biogenerated modified atmospheres. The respiration rates of fermented cocoa beans from Makassar, Sulawesi, Indonesia, were determined under laboratory conditions. Initial insect populations found in these cocoa beans samples consisted of Carpophilus

  18. Chocolate: Modern Science Investigates an Ancient Medicine Cocoa and Wine Polyphenols Modulate Platelet Activation and Function1

    Microsoft Academic Search

    Dietrich Rein; Teresa G. Paglieroni; Debra A. Pearson; Ted Wun; Harold H. Schmitz; Robert Gosselin; Carl L. Keen

    There is speculation that dietary polyphenols can provide cardioprotective effects due to direct antioxidant or antithrombotic mechanisms. We report in vitro and postingestion ex vivo effects of cocoa procya- nidins, a procyanidin-rich cocoa beverage and dealcoholized red wine (DRW) on human platelet activation. In a series of in vitro studies, cocoa procyanidin trimers, pentamers or DRW (3 and 10 mmol\\/L)

  19. Powder treatment process

    DOEpatents

    Weyand, J.D.

    1988-02-09

    Disclosed are: (1) a process comprising spray drying a powder-containing slurry, the slurry containing a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, while reducing the tendency for oxidation of the constituent by including as a liquid constituent of the slurry an organic liquid; (2) a process comprising spray drying a powder-containing slurry, the powder having been pretreated to reduce content of a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, the pretreating comprising heating the powder to react the constituent; and (3) a process comprising reacting ceramic powder, grinding the reacted powder, slurrying the ground powder, spray drying the slurried powder, and blending the dried powder with metal powder. 2 figs.

  20. Powder treatment process

    DOEpatents

    Weyand, John D. (Greensburg, PA)

    1988-01-01

    (1) A process comprising spray drying a powder-containing slurry, the slurry containing a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, while reducing the tendency for oxidation of the constituent by including as a liquid constituent of the slurry an organic liquid; (2) a process comprising spray drying a powder-containing slurry, the powder having been pretreated to reduce content of a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, the pretreating comprising heating the powder to react the constituent; and (3) a process comprising reacting ceramic powder, grinding the reacted powder, slurrying the ground powder, spray drying the slurried powder, and blending the dried powder with metal powder.

  1. Desiccation and Freezing Sensitivity in Recalcitrant Seeds of Tea, Cocoa and Jackfruit

    Microsoft Academic Search

    K. P. S. Chandel; Rekha Chaudhury; J. Radhamani; S. K. Malik

    1995-01-01

    Investigations were undertaken on the desiccation and freezing sensitivity of recalcitrant seeds of three species: tea [Camellia sinensis (L.) O. Kuntze], cocoa (Theobroma cacao L.) and jackfruit (Artocarpus heterophyllus Lamk.). All species showed changes in the physiological characteristics, desiccation and freezing sensitivity of both the seed and the embryonic axes with increasing seed maturity. Fully mature seeds of tea, cocoa

  2. Cardioprotective effects of cocoa: clinical evidence from randomized clinical intervention trials in humans.

    PubMed

    Arranz, Sara; Valderas-Martinez, Palmira; Chiva-Blanch, Gemma; Casas, Rosa; Urpi-Sarda, Mireia; Lamuela-Raventos, Rosa M; Estruch, Ramon

    2013-06-01

    Cocoa is an important source of polyphenols, which comprise 12-18% of its total dry weight. The major phenolic compounds in cocoa and cocoa products are mainly flavonoids such as epicatechin, catechin, and proanthocyanidins. These products contain higher amounts of flavonoids than other polyphenol-rich foods. However, the bioavailability of these compounds depends on other food constituents and their interactions with the food matrix. Many epidemiological and clinical intervention trials have concluded that the ingestion of flavonoids reduces the risk factors of developing cardiovascular disease. This review summarizes the new findings regarding the effects of cocoa and chocolate consumption on cardiovascular risk factors. The mechanisms involved in the cardioprotective effects of cocoa flavonoids include reduction of oxidative stress, inhibition of low-density lipoproteins oxidation and platelet aggregation, vasodilatation of blood vessels, inhibition of the adherence of monocytes to vascular endothelium, promotion of fibrinolysis, and immunomodulatory and anti-inflammatory activity. Scientific evidence supports a cause and effect relationship between consumption of cocoa flavonoids and the maintenance of normal endothelium-dependent vasodilation, which contributes to normal blood flow. However, larger randomized trials are required to definitively establish the impact of cocoa and cocoa products consumption on hard cardiovascular outcomes. PMID:23650217

  3. Anticariogenic effects of polyphenols from plant stimulant beverages (cocoa, coffee, tea)

    Microsoft Academic Search

    Gianmaria F. Ferrazzano; Ivana Amato; Aniello Ingenito; Antonino De Natale; Antonino Pollio

    2009-01-01

    Polyphenols occurring in cocoa, coffee and tea can have a role in the prevention of cariogenic processes, due to their antibacterial action. Cocoa polyphenol pentamers significantly reduce biofilm formation and acid production by Streptococcus mutans and S. sanguinis. In the same way, trigonelline, caffeine and chlorogenic acid occurring in green and roasted coffee interfere with S. mutans adsorption to saliva-coated

  4. Effects of cocoa products\\/dark chocolate on serum lipids: a meta-analysis

    Microsoft Academic Search

    O A Tokede; J M Gaziano; L Djoussé

    2011-01-01

    Cocoa products, which are rich sources of flavonoids, have been shown to reduce blood pressure and the risk of cardiovascular disease. Dark chocolate contains saturated fat and is a source of dietary calories; consequently, it is important to determine whether consumption of dark chocolate adversely affects the blood lipid profile. The objective was to examine the effects of dark chocolate\\/cocoa

  5. Colonial foresters versus agriculturalists: the debate over climate change and cocoa production in the Gold Coast.

    PubMed

    Hodge, Joseph M

    2009-01-01

    This article draws attention to the unfolding debate concerning forest cover loss, climatic change, and declining cocoa production in the Gold Coast (colonial Ghana) during the early twentieth century. It argues that, although desiccationist theory was prevalent, its acceptance among colonial authorities in the Gold Coast was far from hegemonic. There were important dissenting colonial voices, particularly among agriculturalists, who argued that declining cocoa yields were due to plant diseases, most notably cocoa swollen shoot disease. It was based on the latter's non-environmental model of disease transmission, rather than the premises of desiccation science, that the government's postwar "cutting out campaign" of cocoa was predicated. Nevertheless, the foresters' correlation of the deterioration of cocoa areas with fears of desiccation was not without its effects on state practice, providing the rationale for an accelerated program of forest reservations in the 1930s. PMID:19728418

  6. Characterization of Fine Powders

    NASA Astrophysics Data System (ADS)

    Krantz, Matthew; Zhang, Hui; Zhu, Jesse

    Fine powders are used in many applications and across many industries such as powdered paints and pigments, ceramics, petrochemicals, plastics, pharmaceuticals, and bulk and fine chemicals, to name a few. In addition, fine powders must often be handled as a waste by-product, such as ash generated in combustion and gasification processes. In order to correctly design a process and process equipment for application and handling of powders, especially fine powders, it is essential to understand how the powder would behave. Many characterization techniques are available for determining the flow properties of powders; however, care must be taken in selecting the most appropriate technique(s).

  7. The Role of Cocoa as a Cigarette Additive: Opportunities for Product Regulation

    PubMed Central

    Kennedy, Ryan David; Connolly, Gregory N.

    2014-01-01

    Introduction: The 2009 Family Smoking Prevention and Tobacco Control Act prohibited the use of characterizing flavors in cigarettes; however, some of these flavors are still used in cigarettes at varying levels. We reviewed tobacco industry internal documents to investigate the role of one of these flavors, cocoa, with the objective of understanding its relationship to sensory and risk perception, promotion of dependence, and enhancement of attractiveness and acceptability. Methods: We used the Legacy Tobacco Documents Library to identify documents relevant to our research questions. Initial search terms were generated following an examination of published literature on cocoa, other cigarette additives, and sensory and risk perception. Further research questions and search terms were generated based on review of documents generated from the initial search terms. Results: Cocoa is widely applied to cigarettes and has been used by the tobacco industry as an additive since the early 20th century. Cocoa can alter the sensory properties of cigarette smoke, including by providing a more appealing taste and decreasing its harshness. The tobacco industry has experimented with manipulating cocoa levels as a means of achieving sensory properties that appeal to women and youth. Conclusions: Although cocoa is identified as a flavor on tobacco industry Web sites, it may serve other sensory purposes in cigarettes as well. Eliminating cocoa as an additive from tobacco products may affect tobacco product abuse liability by altering smokers’ perceptions of product risk, and decreasing product appeal, especially among vulnerable populations. PMID:24610479

  8. In Vitro Studies on the Antioxidant Property and Inhibition of ?-Amylase, ?-Glucosidase, and Angiotensin I-Converting Enzyme by Polyphenol-Rich Extracts from Cocoa (Theobroma cacao) Bean

    PubMed Central

    Ademosun, Ayokunle O.; Ademiluyi, Adedayo O.; Omojokun, Olasunkanmi S.; Nwanna, Esther E.; Longe, Kuburat O.

    2014-01-01

    Background. This study sought to investigate the antidiabetic and antihypertensive mechanisms of cocoa (Theobroma cacao) bean through inhibition of ?-amylase, ?-glucosidase, angiotensin-1 converting enzyme, and oxidative stress. Methodology. The total phenol and flavonoid contents of the water extractable phytochemicals from the powdered cocoa bean were determined and the effects of the extract on ?-amylase, ?-glucosidase, and angiotensin-1 converting enzyme activities were investigated in vitro. Furthermore, the radicals [1,1-diphenyl-2 picrylhydrazyl (DPPH), 2,2..-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), hydroxyl (OH), and nitric oxide (NO)] scavenging ability and ferric reducing antioxidant property of the extract were assessed. Results. The results revealed that the extract inhibited ?-amylase (1.81 ± 0.22?mg/mL), ?-glucosidase (1.84 ± 0.17?mg/mL), and angiotensin-1 converting enzyme (0.674 ± 0.06?mg/mL [lungs], 1.006 ± 0.08?mg/mL [heart]) activities in a dose-dependent manner and also showed dose-dependent radicals [DPPH (16.94 ± 1.34?mg/mL), NO (6.98 ± 0.886?mg/mL), OH (3.72 ± 0.26?mg/mL), and ABTS (15.7 ± 1.06?mmol/TEAC·g] scavenging ability. Conclusion. The inhibition of ?-amylase, ?-glucosidase, and angiotensin-1 converting enzyme activities by the cocoa bean extract could be part of the possible mechanism by which the extract could manage and/or prevent type-2 diabetes and hypertension. PMID:25295218

  9. Effect of Cocoa Butter and Sunflower Oil Supplementation on Performance, Immunoglobulin, and Antioxidant Vitamin Status of Rats

    PubMed Central

    Ç?nar, Miyase; Yalç?nkaya, ?lkay; Atmaca, Nurgül; Güncüm, Enes

    2014-01-01

    This study investigated the effects of cocoa butter and sunflower oil alone and in combination on performance, some biochemical parameters, immunoglobulin, and antioxidant vitamin status in Wistar rats. Forty-eight male rats were assigned to four groups, consisting of 12 rats with 3 replicates. Control received balanced rat diet without oil, cocoa butter group received 3.5% cocoa butter, sunflower oil group received 3.5% sunflower oil, the last group received 1.75% sunflower oil + 1.75% cocoa butter supplementation in the rat diet for 8 weeks. The total feed consumption in sunflower oil group was statistically lower than in the other groups. The serum creatinine level was decreased in cocoa butter group compared to control. Triglyceride and VLDL cholesterol levels were decreased in only sunflower oil and only cocoa butter groups as compared to control. The level of Ig M was statistically lower in cocoa butter and cocoa butter + sunflower oil groups than in control and sunflower oil groups. There were no statistically important difference in vitamin concentrations among trial groups. It was concluded that the supplementation of cocoa butter in diet decreased Ig M level, while the supplementation of cocoa butter and sunflower oil alone decreased the triglyceride and VLDL cholesterol levels. PMID:25136602

  10. Application of a molecular sensory science approach to alkalized cocoa (Theobroma cacao): structure determination and sensory activity of nonenzymatically C-glycosylated flavan-3-ols.

    PubMed

    Stark, Timo; Hofmann, Thomas

    2006-12-13

    Application of comparative taste dilution analyses on nonalkalized and alkalized cocoa powder revealed the detection of a velvety, smoothly astringent tasting fraction, which was predominantly present in the alkalized sample. LC-MS/MS analysis, 1D- and 2D-NMR, and CD spectroscopy as well as model alkalization reactions led to the unequivocal identification of the velvety, smoothly astringent molecules as a series of catechin- and epicatechin-C-glycopyranosides. Besides the previously reported (-)-epicatechin-8-C-beta-D-galactopyranoside, additional flavan-3-ol-C-glycosides, namely, (-)-epicatechin-8-C-beta-D-glucopyranoside, (-)-catechin-8-C-beta-D-glucopyranoside, (-)-catechin-6-C-beta-D-glucopyranoside, (-)-epicatechin-6-C-beta-D-glucopyranoside, (-)-catechin-8-C-beta-D-galactopyranoside, (-)-catechin-6-C-beta-D-galactopyranoside, (-)-catechin-6-C,8-C-beta-D-diglucopyranoside, (-)-epicatechin-6-C,8-C-beta-D-digalactopyranoside, (-)-catechin-6-C,8-C-beta-D-digalactopyranoside, and epicatechin-6-C,8-C-beta-D-diglucopyranoside, were identified for the first time in cocoa. Most surprisingly, these phenol glycoconjugates were demonstrated by model experiments to be formed via a novel nonenzymatic C-glycosylation of flavan-3-ols. Using the recently developed half-tongue test, human recognition thresholds for the astringent and mouth-drying oral sensation were determined to be between 1.1 and 99.5 micro mol/L (water) depending on the sugar and the intramolecular binding position as well as the aglycone. PMID:17147440

  11. Impact of fermentation, drying, roasting and Dutch processing on flavan-3-ol stereochemistry in cacao beans and cocoa ingredients

    PubMed Central

    2011-01-01

    This paper reports a systematic study of the level of flavan-3-ol monomers during typical processing steps as cacao beans are dried, fermented and roasted and the results of Dutch-processing. Methods have been used that resolve the stereoisomers of epicatechin and catechin. In beans harvested from unripe and ripe cacao pods, we find only (-)-epicatechin and (+)-catechin with (-)-epicatechin being by far the predominant isomer. When beans are fermented there is a large loss of both (-)-epicatechin and (+)-catechin, but also the formation of (-)-catechin. We hypothesize that the heat of fermentation may, in part, be responsible for the formation of this enantiomer. When beans are progressively roasted at conditions described as low, medium and high roast conditions, there is a progressive loss of (-)-epicatechin and (+)-catechin and an increase in (-)-catechin with the higher roast levels. When natural and Dutch-processed cacao powders are analyzed, there is progressive loss of both (-)-epicatechin and (+)-catechin with lesser losses of (-)-catechin. We thus observe that in even lightly Dutch-processed powder, the level of (-)-catechin exceeds the level of (-)-epicatechin. The results indicate that much of the increase in the level of (-)-catechin observed during various processing steps may be the result of heat-related epimerization from (-)-epicatechin. These results are discussed with reference to the reported preferred order of absorption of (-)-epicatechin > (+)-catechin > (-)-catechin. These results are also discussed with respect to the balance that must be struck between the beneficial impact of fermentation and roasting on chocolate flavor and the healthful benefits of chocolate and cocoa powder that result in part from the flavan-3-ol monomers. PMID:21917164

  12. Precision powder feeder

    DOEpatents

    Schlienger, M. Eric (Albuquerque, NM); Schmale, David T. (Albuquerque, NM); Oliver, Michael S. (Sandia Park, NM)

    2001-07-10

    A new class of precision powder feeders is disclosed. These feeders provide a precision flow of a wide range of powdered materials, while remaining robust against jamming or damage. These feeders can be precisely controlled by feedback mechanisms.

  13. 21 CFR 163.150 - Sweet cocoa and vegetable fat coating.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Safe and suitable vegetable derived fats, oils, and stearins other...or usual name of the vegetable derived fat ingredient...sweet cocoa and ___ oil coating”, the blank...name of the specific vegetable fat...

  14. 21 CFR 163.150 - Sweet cocoa and vegetable fat coating.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Safe and suitable vegetable derived fats, oils, and stearins other...or usual name of the vegetable derived fat ingredient...sweet cocoa and ___ oil coating”, the blank...name of the specific vegetable fat...

  15. 21 CFR 163.150 - Sweet cocoa and vegetable fat coating.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Safe and suitable vegetable derived fats, oils, and stearins other...or usual name of the vegetable derived fat ingredient...sweet cocoa and ___ oil coating”, the blank...name of the specific vegetable fat...

  16. 21 CFR 163.150 - Sweet cocoa and vegetable fat coating.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Safe and suitable vegetable derived fats, oils, and stearins other...or usual name of the vegetable derived fat ingredient...sweet cocoa and ___ oil coating”, the blank...name of the specific vegetable fat...

  17. Aluminum powder metallurgy processing

    SciTech Connect

    Flumerfelt, J.F.

    1999-02-12

    The objective of this dissertation is to explore the hypothesis that there is a strong linkage between gas atomization processing conditions, as-atomized aluminum powder characteristics, and the consolidation methodology required to make components from aluminum powder. The hypothesis was tested with pure aluminum powders produced by commercial air atomization, commercial inert gas atomization, and gas atomization reaction synthesis (GARS). A comparison of the GARS aluminum powders with the commercial aluminum powders showed the former to exhibit superior powder characteristics. The powders were compared in terms of size and shape, bulk chemistry, surface oxide chemistry and structure, and oxide film thickness. Minimum explosive concentration measurements assessed the dependence of explosibility hazard on surface area, oxide film thickness, and gas atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization oxidation of aluminum powder. An Al-Ti-Y GARS alloy exposed in ambient air at different temperatures revealed the effect of reactive alloy elements on post-atomization powder oxidation. The pure aluminum powders were consolidated by two different routes, a conventional consolidation process for fabricating aerospace components with aluminum powder and a proposed alternative. The consolidation procedures were compared by evaluating the consolidated microstructures and the corresponding mechanical properties. A low temperature solid state sintering experiment demonstrated that tap densified GARS aluminum powders can form sintering necks between contacting powder particles, unlike the total resistance to sintering of commercial air atomization aluminum powder.

  18. A design of sample survey for estimation of cocoa production in Western Nigeria 

    E-print Network

    Salami, Shakiru Okunola

    1973-01-01

    difficulties and cost. These attempts involve agricultural regions as 'strata', vill'ages as 'primary sampling units p and cocoa operators as 'secondary sampling units' The design enunciated in this thesis takes the f'ollowing factors into consideration: (i... those of yeasant, farmers, The sampling schemes in the area and list frames are identical. The schemes invo1ve the administrative Divisions as primary strata, the villages as primary sampling units, and cocoa orchards as secon- dary sampling units...

  19. Cocoa Flavonoid-Enriched Diet Modulates Systemic and Intestinal Immunoglobulin Synthesis in Adult Lewis Rats

    PubMed Central

    Massot-Cladera, Malen; Franch, Àngels; Castellote, Cristina; Castell, Margarida; Pérez-Cano, Francisco J.

    2013-01-01

    Previous studies have reported that a diet containing 10% cocoa, a rich source of flavonoids, has immunomodulatory effects on rats and, among others effects, is able to attenuate the immunoglobulin (Ig) synthesis in both systemic and intestinal compartments. The purpose of the present study was focused on investigating whether these effects were attributed exclusively to the flavonoid content or to other compounds present in cocoa. To this end, eight-week-old Lewis rats were fed, for two weeks, either a standard diet or three isoenergetic diets containing increasing proportions of cocoa flavonoids from different sources: one with 0.2% polyphenols from conventional defatted cocoa, and two others with 0.4% and 0.8% polyphenols, respectively, from non-fermented cocoa. Diet intake and body weight were monitored and fecal samples were obtained throughout the study to determine fecal pH, IgA, bacteria proportions, and IgA-coated bacteria. Moreover, IgG and IgM concentrations in serum samples collected during the study were quantified. At the end of the dietary intervention no clear changes of serum IgG or IgM concentrations were quantified, showing few effects of cocoa polyphenol diets at the systemic level. However, in the intestine, all cocoa polyphenol-enriched diets attenuated the age-related increase of both fecal IgA and IgA-coated bacteria, as well as the proportion of bacteria in feces. As these effects were not dependent on the dose of polyphenol present in the diets, other compounds and/or the precise polyphenol composition present in cocoa raw material used for the diets could be key factors in this effect. PMID:23966108

  20. Comparative study of commercially available cocoa products in terms of their bioactive composition

    Microsoft Academic Search

    Ana Belš?ak; Draženka Komes; Dunja Horži?; Karin Kova?evi? Gani?; Damir Karlovi?

    2009-01-01

    Recent trends in food marketing suggest that cocoa products, besides being favourite sweets among consumers, also present multiple-benefit foodstuffs, which are becoming objects of increased scientific research, mainly because of their interesting phytochemical composition. UV\\/VIS spectrophotometric and high-performance liquid chromatography (HPLC-PDA) methods were applied in order to compare the composition of polyphenols and methylxanthines in commercial cocoa products affected by

  1. Cocoa extract protects against early alcohol-induced liver injury in the rat

    Microsoft Academic Search

    Stephen E McKim; Akira Konno; Erwin Gäbele; Takehiko Uesugi; Mathias Froh; Helmut Sies; Ronald G Thurman; Gavin E Arteel

    2002-01-01

    Oxidants have been shown to be involved in alcohol-induced liver injury. This study was designed to determine whether cocoa flavonoid extract, composed mostly of epicatechin and epicatechin oligomers, protects against early alcohol-induced liver injury in rats. Male Wistar rats were fed high-fat liquid diets with or without ethanol (10–14g\\/kg per day) and cocoa extract (400mg\\/kg per day) continuously for 4

  2. Isolation and thermal characterization of high-melting seed crystals formed during cocoa butter solidification

    Microsoft Academic Search

    Thomas R. Davis; Paul S. Dimick

    1989-01-01

    Seed crystals which formed during early stages of cocoa butter solidification have been isolated and determined to have extremely\\u000a high melting points. The melting points of the seed crystals generally exceeded 60C, in contrast to cocoa butter, which melts\\u000a between 30–35C. In addition, the melting point of the seed crystals decreased as a function of crystal growth time. Evidence\\u000a suggests

  3. Implication of Bacillus sp. in the production of pectinolytic enzymes during cocoa fermentation

    Microsoft Academic Search

    Honoré G. Ouattara; Ban L. Koffi; Germain T. Karou; Abdourahamane Sangaré; Sebastien L. Niamke; Jacques K. Diopoh

    2008-01-01

    The role of bacilli in cocoa fermentation is not well known. Their potential of production of pectinolytic enzymes during\\u000a this process was evaluated. Bacillus growth was monitored and pectinolytic strains were screened for their use of pectin as sole carbon source. Effects of cocoa\\u000a fermentation parameters susceptible to influence on enzyme production were analysed. Among 98 strains isolated, 90 were

  4. Optimization of cocoa butter analog synthesis variables using neural networks and genetic algorithm.

    PubMed

    Shekarchizadeh, Hajar; Tikani, Reza; Kadivar, Mahdi

    2014-09-01

    Cocoa butter analog was prepared from camel hump fat and tristearin by enzymatic interesterification in supercritical carbon dioxide (SC-CO2) using immobilized Thermomyces lanuginosus lipase (Lipozyme TL IM) as a biocatalyst. Optimal process conditions were determined using neural networks and genetic algorithm optimization. Response surfaces methodology was used to design the experiments to collect data for the neural network modelling. A general regression neural network model was developed to predict the response of triacylglycerol (TAG) distribution of cocoa butter analog from the process pressure, temperature, tristearin/camel hump fat ratio, water content, and incubation time. A genetic algorithm was used to search for a combination of the process variables for production of most similar cocoa butter analog to the corresponding cocoa butter. The combinations of the process variables during genetic algorithm optimization were evaluated using the neural network model. The pressure of 10 MPa; temperature of 40 °C; SSS/CHF ratio of 0.6:1; water content of 13 % (w/w); and incubation time of 4.5 h were found to be the optimum conditions to achieve the most similar cocoa butter analog to the corresponding cocoa butter. PMID:25190869

  5. Biodiversity conservation, ecosystem functioning, and economic incentives under cocoa agroforestry intensification.

    PubMed

    Bisseleua, D H B; Missoup, A D; Vidal, S

    2009-10-01

    World chocolate demand is expected to more than double by 2050. Decisions about how to meet this challenge will have profound effects on tropical rainforests and wild species in cocoa-producing countries. Cocoa, "the chocolate tree," is traditionally produced under a diverse and dense canopy of shade trees that provide habitat for a high diversity of organisms. The current trend to reduce or eliminate shade cover raises concerns about the potential loss of biodiversity. Nevertheless, few studies have assessed the ecological consequences and economic trade-offs under different management options in cocoa plantations. Here we describe the relationships between ant ecology (species richness, community composition, and abundance) and vegetation structure, ecosystem functions, and economic profitability under different land-use management systems in 17 traditional cocoa forest gardens in southern Cameroon. We calculated an index of profitability, based on the net annual income per hectare. We found significant differences associated with the different land-use management systems for species richness and abundance of ants and species richness and density of trees. Ant species richness was significantly higher in floristically and structurally diverse, low-intensity, old cocoa systems than in intensive young systems. Ant species richness was significantly related to tree species richness and density. We found no clear relationship between profitability and biodiversity. Nevertheless, we suggest that improving the income and livelihood of smallholder cocoa farmers will require economic incentives to discourage further intensification and ecologically detrimental loss of shade cover. Certification programs for shade-grown cocoa may provide socioeconomic incentives to slow intensification. PMID:19765036

  6. Shade Tree Diversity, Cocoa Pest Damage, Yield Compensating Inputs and Farmers' Net Returns in West Africa

    PubMed Central

    Daghela Bisseleua, Hervé Bertin; Fotio, Daniel; Yede; Missoup, Alain Didier; Vidal, Stefan

    2013-01-01

    Cocoa agroforests can significantly support biodiversity, yet intensification of farming practices is degrading agroforestry habitats and compromising ecosystem services such as biological pest control. Effective conservation strategies depend on the type of relationship between agricultural matrix, biodiversity and ecosystem services, but to date the shape of this relationship is unknown. We linked shade index calculated from eight vegetation variables, with insect pests and beneficial insects (ants, wasps and spiders) in 20 cocoa agroforests differing in woody and herbaceous vegetation diversity. We measured herbivory and predatory rates, and quantified resulting increases in cocoa yield and net returns. We found that number of spider webs and wasp nests significantly decreased with increasing density of exotic shade tree species. Greater species richness of native shade tree species was associated with a higher number of wasp nests and spider webs while species richness of understory plants did not have a strong impact on these beneficial species. Species richness of ants, wasp nests and spider webs peaked at higher levels of plant species richness. The number of herbivore species (mirid bugs and cocoa pod borers) and the rate of herbivory on cocoa pods decreased with increasing shade index. Shade index was negatively related to yield, with yield significantly higher at shade and herb covers<50%. However, higher inputs in the cocoa farms do not necessarily result in a higher net return. In conclusion, our study shows the importance of a diverse shade canopy in reducing damage caused by cocoa pests. It also highlights the importance of conservation initiatives in tropical agroforestry landscapes. PMID:23520451

  7. Multiple feed powder splitter

    DOEpatents

    Lewis, Gary K. (Los Alamos, NM); Less, Richard M. (Los Alamos, NM)

    2002-01-01

    A device for providing uniform powder flow to the nozzles when creating solid structures using a solid fabrication system such as the directed light fabrication (DLF) process. In the DLF process, gas entrained powders are passed through the focal point of a moving high-power laser light which fuses the particles in the powder to a surface being built up in layers. The invention is a device providing uniform flow of gas entrained powders to the nozzles of the DLF system. The device comprises a series of modular splitters which are slidably interconnected and contain an integral flow control mechanism. The device can take the gas entrained powder from between one to four hoppers and split the flow into eight tubular lines which feed the powder delivery nozzles of the DLF system.

  8. Which Powder is It?

    NSDL National Science Digital Library

    Sciencenter

    2014-08-27

    In this chemistry challenge, learners identify an unknown white powder by comparing it with common household powders. Learners first explore what happens when baking soda, baking powder, and washing soda are mixed with water, vinegar, and PHTH (the indicator phenolphthalein mixed with alcohol and water). Learners then work to identify the unknown based on how it reacts with the known solutions. This is a simplified form of "qualitative analysis," which was historically an important approach chemists used for identifying unknown samples.

  9. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-08-05

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of ternary mixtures consisting of: Ni powder, Cu powder, and Al powder, Ni powder, Cr powder, and Al powder; Ni powder, W powder and Al powder; Ni powder, V powder, and Al powder; Ni powder, Mo powder, and Al powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  10. PRODUCTION OF COCOA BUTTER-LIKE FATS BY THE LIPASE-CATALYZED INTERESTERIFICATION OF PALM OIL AND HYDROGENATED SOYBEAN OIL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cocoa butter-like fats were prepared from refined, bleached and deodorized palm oil (RBD-PO) and fully hydrogenated soy oil (HSO) by enzymatic interesterification at various weight ratios of substrates. The cocoa butter-like fats were isolated from the crude interesterification mixture by fractiona...

  11. Rapid differentiation of Ghana cocoa beans by FT-NIR spectroscopy coupled with multivariate classification.

    PubMed

    Teye, Ernest; Huang, Xingyi; Dai, Huang; Chen, Quansheng

    2013-10-01

    Quick, accurate and reliable technique for discrimination of cocoa beans according to geographical origin is essential for quality control and traceability management. This current study presents the application of Near Infrared Spectroscopy technique and multivariate classification for the differentiation of Ghana cocoa beans. A total of 194 cocoa bean samples from seven cocoa growing regions were used. Principal component analysis (PCA) was used to extract relevant information from the spectral data and this gave visible cluster trends. The performance of four multivariate classification methods: Linear discriminant analysis (LDA), K-nearest neighbors (KNN), Back propagation artificial neural network (BPANN) and Support vector machine (SVM) were compared. The performances of the models were optimized by cross validation. The results revealed that; SVM model was superior to all the mathematical methods with a discrimination rate of 100% in both the training and prediction set after preprocessing with Mean centering (MC). BPANN had a discrimination rate of 99.23% for the training set and 96.88% for prediction set. While LDA model had 96.15% and 90.63% for the training and prediction sets respectively. KNN model had 75.01% for the training set and 72.31% for prediction set. The non-linear classification methods used were superior to the linear ones. Generally, the results revealed that NIR Spectroscopy coupled with SVM model could be used successfully to discriminate cocoa beans according to their geographical origins for effective quality assurance. PMID:23770507

  12. Effect of cocoa products and flavanols on platelet aggregation in humans: a systematic review.

    PubMed

    Peluso, Ilaria; Palmery, Maura; Serafini, Mauro

    2015-07-01

    Previous evidence suggested an active role of cocoa products and flavanols in modulating platelet aggregation. However, cocoa flavanols are characterized by a low bioavailability that can deeply affect their presence in biological fluids and raise questions on their biological effect in humans. We performed a systematic search on Medline, Embase, Cochrane and ProQuest databases, until April 2015, on the effect of cocoa products on platelet aggregation in human intervention studies. We identified 13 interventions, of which only five involved repeated administration. Different effects were observed on the basis of the platelet aggregation test used, whereas neither a longer duration of treatment nor a higher dose was associated with a higher inhibition of platelet aggregation. In conclusion, the reviewed results suggest that consumption of cocoa products in bolus administration positively affects platelet aggregation in both healthy subjects and diseased patients. On the other hand, more evidence is required in order to assess the effect of long-term cocoa product ingestion and to identify the bioactive components involved. PMID:26040467

  13. Cocoa-rich diet ameliorates hepatic insulin resistance by modulating insulin signaling and glucose homeostasis in Zucker diabetic fatty rats.

    PubMed

    Cordero-Herrera, Isabel; Martín, María Ángeles; Escrivá, Fernando; Álvarez, Carmen; Goya, Luis; Ramos, Sonia

    2015-07-01

    Insulin resistance is the primary characteristic of type 2 diabetes and results from insulin signaling defects. Cocoa has been shown to exert anti-diabetic effects by lowering glucose levels. However, the molecular mechanisms responsible for this preventive activity and whether cocoa exerts potential beneficial effects on the insulin signaling pathway in the liver remain largely unknown. Thus, in this study, the potential anti-diabetic properties of cocoa on glucose homeostasis and insulin signaling were evaluated in type 2 diabetic Zucker diabetic fatty (ZDF) rats. Male ZDF rats were fed a control or cocoa-rich diet (10%), and Zucker lean animals received the control diet. ZDF rats supplemented with cocoa (ZDF-Co) showed a significant decrease in body weight gain, glucose and insulin levels, as well as an improved glucose tolerance and insulin resistance. Cocoa-rich diet further ameliorated the hepatic insulin resistance by abolishing the increased serine-phosphorylated levels of the insulin receptor substrate 1 and preventing the inactivation of the glycogen synthase kinase 3/glycogen synthase pathway in the liver of cocoa-fed ZDF rats. The anti-hyperglycemic effect of cocoa appeared to be at least mediated through the decreased levels of hepatic phosphoenolpyruvate carboxykinase and increased values of glucokinase and glucose transporter 2 in the liver of ZDF-Co rats. Moreover, cocoa-rich diet suppressed c-Jun N-terminal kinase and p38 activation caused by insulin resistance. These findings suggest that cocoa has the potential to alleviate both hyperglycemia and hepatic insulin resistance in type 2 diabetic ZDF rats. PMID:25814291

  14. Influence of Cocoa Flavanols and Procyanidins on Free Radical-induced Human Erythrocyte Hemolysis

    PubMed Central

    Zhu, Qin Yan; Schramm, Derek D.; Gross, Heidrun B.; Holt, Roberta R.; Kim, Sun H.; Yamaguchi, Tomoko; Kwik-Uribe, Catherine L.; Keen, Carl L.

    2005-01-01

    Cocoa can be a rich source of antioxidants including the flavan-3-ols, epicatechin and catechin, and their oligomers (procyanidins). While these flavonoids have been reported to reduce the rate of free radical-induced erythrocyte hemolysis in experimental animal models, little is known about their effect on human erythrocyte hemolysis. The major objective of this work was to study the effect of a flavonoid-rich cocoa beverage on the resistance of human erythrocytes to oxidative stress. A second objective was to assess the effects of select purified cocoa flavonoids, epicatechin, catechin, the procyanidin Dimer B2 and one of its major metabolites, 3?-O-methyl epicatechin, on free radical-induced erythrocyte hemolysis in vitro. Peripheral blood was obtained from 8 healthy subjects before and 1, 2, 4 and 8 h after consuming a flavonoid-rich cocoa beverage that provided 0.25 g/kg body weight (BW), 0.375 or 0.50 g/kg BW of cocoa. Plasma flavanol and dimer concentrations were determined for each subject. Erythrocyte hemolysis was evaluated using a controlled peroxidation reaction. Epicatechin, catechin, 3?-O-methyl epicatechin and (-)-epicatechin-(4? > 8)epicatechin (Dimer B2) were detected in the plasma within 1 h after the consumption of the beverage. The susceptibility of erythrocytes to hemolysis was reduced significantly following the consumption of the beverages. The duration of the lag time, which reflects the capacity of cells to buffer free radicals, was increased. Consistent with the above, the purified flavonoids, epicatechin, catechin, Dimer B2 and the metabolite 3?-O-methyl epicatechin, exhibited dose-dependent protection against AAPH-induced erythrocyte hemolysis at concentrations ranging from 2.5 to 20 ?M. Erythrocytes from subjects consuming flavonoid-rich cocoa show reduced susceptibility to free radical-induced hemolysis (p < 0.05). PMID:15712596

  15. Multi-element, multi-compound isotope profiling as a means to distinguish the geographical and varietal origin of fermented cocoa (Theobroma cacao L.) beans.

    PubMed

    Diomande, Didier; Antheaume, Ingrid; Leroux, Maël; Lalande, Julie; Balayssac, Stéphane; Remaud, Gérald S; Tea, Illa

    2015-12-01

    Multi-element stable isotope ratios have been assessed as a means to distinguish between fermented cocoa beans from different geographical and varietal origins. Isotope ratios and percentage composition for C and N were measured in different tissues (cotyledons, shells) and extracts (pure theobromine, defatted cocoa solids, protein, lipids) obtained from fermented cocoa bean samples. Sixty-one samples from 24 different geographical origins covering all four continental areas producing cocoa were analyzed. Treatment of the data with unsupervised (Principal Component Analysis) and supervised (Partial Least Squares Discriminant Analysis) multiparametric statistical methods allowed the cocoa beans from different origins to be distinguished. The most discriminant variables identified as responsible for geographical and varietal differences were the ?(15)N and ?(13)C values of cocoa beans and some extracts and tissues. It can be shown that the isotope ratios are correlated with the altitude and precipitation conditions found in the different cocoa-growing regions. PMID:26041233

  16. Relation of fat bloom in chocolate to polymorphic transition of cocoa butter

    Microsoft Academic Search

    J. Bricknell; R. W. Hartel

    1998-01-01

    A special chocolate with spray-dried sugar (50:50 w\\/w sucrose\\/20 Dextrose Equivalent corn syrup solids) was made to study\\u000a the polymorphic changes in cocoa butter crystals using X-ray diffraction. Anhydrous milk fat (AMF) and high-, middle-, and\\u000a low-melting milk fat fractions were used to replace 2% (w\\/w) of cocoa butter. Chocolates were tempered, and the consistency\\u000a of temper among chocolate samples

  17. Flavor formation and character in cocoa and chocolate: a critical review.

    PubMed

    Afoakwa, Emmanuel Ohene; Paterson, Alistair; Fowler, Mark; Ryan, Angela

    2008-10-01

    Chocolate characters not only originate in flavor precursors present in cocoa beans, but are generated during post-harvest treatments and transformed into desirable odor notes in the manufacturing processes. Complex biochemical modifications of bean constituents are further altered by thermal reactions in roasting and conching and in alkalization. However, the extent to which the inherent bean constituents from the cocoa genotype, environmental factors, post-harvest treatment, and processing technologies influence chocolate flavor formation and relationships with final flavor quality, has not been clear. With increasing speciality niche products in chocolate confectionery, greater understanding of factors contributing to the variations in flavor character would have significant commercial implications. PMID:18788009

  18. Sintering titanium powders

    SciTech Connect

    Gerdemann, Stephen J.; Alman, David E.

    2005-09-01

    Recently, there has been renewed interest in low-cost titanium. Near-net-shape powder metallurgy offers the potential of manufacturing titanium articles without costly and difficult forming and machining operations; hence, processing methods such as conventional press-and-sinter, powder forging and powder injection molding are of interest. The sintering behavior of a variety of commercial and experimental titanium powders was studied. Commercial powders were acquired that were produced different routes: (i) sponge fines from the primary titanium processing; (ii) via the hydride-dehydride process; and (iii) gas atomization. The influence of vacuum sintering time (0.5 to 32 hrs) and temperature (1200, 1275 or 1350°C) on the microstructure (porosity present) of cold pressed powders was studied. The results are discussed in terms of the difference in powder characteristics, with the aim of identify the characteristics required for full density via press-and-sinter processing. Near-net-shape tensile bars were consolidated via cold pressed and sintered. After sintering, a sub-set of the tensile bars was hot-isostatic pressed (HIPed). The microstructure and properties of the bars were compared in the sintered and HIPed conditions.

  19. Compaction of Titanium Powders

    SciTech Connect

    Stephen J. Gerdemann; Paul D. Jablonski

    2010-11-01

    Accurate modeling of powder densification has been an area of active research for more than 60 years. The earliest efforts were focused on linearization of the data because computers were not readily available to assist with curve-fitting methods. In this work, eight different titanium powders (three different sizes of sponge fines <150 ?m, <75 ?m, and < 45 ?m; two different sizes of a hydride-dehydride [HDH] <75 ?m and < 45 ?m; an atomized powder; a commercially pure [CP] Ti powder from International Titanium Powder [ITP]; and a Ti 6 4 alloy powder) were cold pressed in a single-acting die instrumented to collect stress and deformation data during compaction. From these data, the density of each compact was calculated and then plotted as a function of pressure. The results show that densification of all the powders, regardless of particle size, shape, or chemistry, can be modeled accurately as the sum of an initial density plus the sum of a rearrangement term and a work-hardening term. These last two terms are found to be a function of applied pressure and take the form of an exponential rise.

  20. Compaction of Titanium Powders

    SciTech Connect

    Gerdemann, Stephen,J; Jablonski, Paul, J

    2011-05-01

    Accurate modeling of powder densification has been an area of active research for more than 60 years. The earliest efforts were focused on linearization of the data because computers were not readily available to assist with curve-fitting methods. In this work, eight different titanium powders (three different sizes of sponge fines<150 {micro}m,<75 {micro}m, and<45 {micro}m; two different sizes of a hydride-dehydride [HDH]<75 {micro}m and<45 {micro}m; an atomized powder; a commercially pure [CP] Ti powder from International Titanium Powder [ITP]; and a Ti 6 4 alloy powder) were cold pressed in a single-acting die instrumented to collect stress and deformation data during compaction. From these data, the density of each compact was calculated and then plotted as a function of pressure. The results show that densification of all the powders, regardless of particle size, shape, or chemistry, can be modeled accurately as the sum of an initial density plus the sum of a rearrangement term and a work-hardening term. These last two terms are found to be a function of applied pressure and take the form of an exponential rise.

  1. Influence of sugar type on the bioavailability of cocoa flavanols.

    PubMed

    Rodriguez-Mateos, Ana; Oruna-Concha, Maria Jose; Kwik-Uribe, Catherine; Vidal, Alberto; Spencer, Jeremy P E

    2012-12-28

    The beneficial effects of cocoa on vascular function are mediated by the absorption of monomeric flavanols into the circulation from the small intestine. As such, an understanding of the impact of the food matrix on the delivery of flavanols to the circulation is critical in assessing the potential vascular impact of a food. In the present study, we investigated the impact of carbohydrate type on flavanol absorption and metabolism from chocolate. A randomised, double-blind, three-arm cross-over study was conducted, where fifteen volunteers were randomly assigned to either a high-flavanol (266 mg) chocolate containing maltitol, a high-flavanol (251 mg) chocolate with sucrose or a low-flavanol (48 mg) chocolate with sucrose. Test chocolates were matched for micro- and macronutrients, including the alkaloids theobromine and caffeine, and were similar in taste and appearance. Total flavanol absorption was lower after consumption of the maltitol-containing test chocolate compared with following consumption of its sucrose-containing equivalent (P = 0·002). Although the O-methylation pattern observed for absorbed flavanols was unaffected by sugar type, individual levels of unmethylated ( - )-epicatechin metabolites, 3'-O-methyl-epicatechin and 4'-O-methyl-epicatechin metabolites were lower for the maltitol-containing test chocolate compared with the sucrose-containing equivalent. Despite a reduction in the total plasma pool of flavanols, the maximum time (T max) was unaffected. The present data indicate that full assessment of intervention treatments is vital in future intervention trials with flavanols and that carbohydrate content is an important determinant for the optimal delivery of flavanols to the circulation. PMID:22397837

  2. Mystery Powder Investigation

    NSDL National Science Digital Library

    Rachel HallettNjuguna

    2012-07-27

    Students will use their skills as scientists to identify a mystery white powder. This lesson is a hands-on, engaging way to build students' understanding of physical and chemical properties of several common compounds.

  3. Talcum Powder and Cancer

    MedlinePLUS

    ... and risk of endometrial cancer in postmenopausal women. Cancer Causes Control . 2012;23:1673?1680. Gertig DM, Hunter ... Use of talcum powder and endometrial cancer risk. Cancer Causes Control . 2012;2:513?519. Rosenblatt KA, Weiss ...

  4. Gelcasting superalloy powders

    SciTech Connect

    Janney, M.A.

    1995-12-31

    Gelcasting is a process for forming inorganic powders into complex shapes. It was originally developed for ceramic powders. A slurry of powder and a monomer solution is poured in to mold and polymerized in-situ to form gelled parts. Typically, only 2-4 wt % Polymer is used. The process has both aqueous and nonaqueous versions. Gelcasting is a generic process and has been used to produce ceramic parts from over a dozen different ceramic compositions ranging from alumina-based refractories to high-performance silicon nitride. Recently, gelcasting has been applied to forming superalloy powders into complex shapes. This application has posed several challenges not previously encountered in ceramics. In particular, problems were caused by the larger particle size and the higher density of the particles. Additional problems were encountered with binder removal. How these problems were overcome will be described.

  5. POWDER COAT APPLICATIONS

    EPA Science Inventory

    The report discusses an investigation of critical factors that affect the use of powder coatings on the environment, cost, quality, and production. The investigation involved a small business representative working with the National Defense Center for Environmental Excellence (ND...

  6. Hepagene (PowderJect).

    PubMed

    Jones, Taff

    2002-07-01

    Celltech Group (formerly Medeva) developed Hepagene, a recombinant polyvalent vaccine with potential activity against hepatitis B virus infections [353474]. In September 2000, PowderJect acquired the product as part of its acquisition of Celltech's vaccine manufacturing business [381557]. In July 2001, PowderJect reported that evaluation was nearing completion. At this time, the company expected to launch the vaccine in the coming months [443490]. Hepagene is a polyvalent vaccine with S, pre-S1 and pre-S2 hepatitis B epitopes forming the basis of its antigenicity. Additionally, these surface markers have been glycosylated in order to resemble the live virus more closely [254780]. By June 2000, Celltech and PowderJect were evaluating Hepagene, utilizing PowderJect's needle-less injection technology [379536]. In December 1999, Lehman Brothers predicted that the product had a 50% chance of reaching the treatment (rather than prevention) market, with potential peak sales of US $600 million [352078]. PMID:12186276

  7. Interactions among chemical components of Cocoa tea (Camellia ptilophylla Chang), a naturally low caffeine-containing tea species.

    PubMed

    Lin, Xiaorong; Chen, Zhongzheng; Zhang, Yuanyuan; Gao, Xiong; Luo, Wei; Li, Bin

    2014-06-01

    In the 1980s, a novel tea species, Cocoa tea (Camellia ptilophylla Chang), was discovered in Southern China with surprisingly low caffeine content (0.2% by dry weight). Although its health promoting characteristics have been known for a while, a very limited amount of scientific research has been focused on Cocoa tea. Herein, a systematic study on Cocoa tea and its chemical components, interactions and bioactivities was performed. YD tea (Yunnan Daye tea, Camellia sinensis), a tea species with a high caffeine content (5.8% by dry weight), was used as a control. By UV-Vis spectrometry, High Performance Liquid Chromatography (HPLC), and Flame Atomic Absorption Spectrometry (FAAS) for chemical composition analysis, C-2 epimeric isomers of tea catechins and theobromine were found to be the major catechins and methylxanthine in Cocoa tea, respectively. More gallated catechins, methylxanthines, and proteins were detected in Cocoa tea compared with YD tea. Moreover, the tendency of major components in Cocoa tea for precipitation was significantly higher than that in YD tea. Catechins, methylxanthines, proteins, iron, calcium, and copper were presumed to be the origins of molecular interactions in Cocoa tea and YD tea. The interactions between catechins and methylxanthines were highly related to the galloyl moiety in catechins and methyl groups in methylxanthines. In vitro anti-inflammatory activity assays revealed that Cocoa tea was a more potent inhibitor of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated macrophage cells (RAW 264.7) than YD tea. This study constructs a solid phytochemical foundation for further research on the mechanisms of molecular interactions and the integrated functions of Cocoa tea. PMID:24699984

  8. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-08-19

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  9. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-08-26

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  10. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2005-01-25

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  11. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goval, Amit; Williams, Robert K.; Kroeger, Donald M.

    2005-06-07

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  12. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2004-09-28

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  13. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2005-05-10

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  14. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-07-29

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  15. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2004-09-14

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  16. Chocolate and the brain: neurobiological impact of cocoa flavanols on cognition and behavior.

    PubMed

    Sokolov, Alexander N; Pavlova, Marina A; Klosterhalfen, Sibylle; Enck, Paul

    2013-12-01

    Cocoa products and chocolate have recently been recognized as a rich source of flavonoids, mainly flavanols, potent antioxidant and anti-inflammatory agents with established benefits for cardiovascular health but largely unproven effects on neurocognition and behavior. In this review, we focus on neuromodulatory and neuroprotective actions of cocoa flavanols in humans. The absorbed flavonoids penetrate and accumulate in the brain regions involved in learning and memory, especially the hippocampus. The neurobiological actions of flavanols are believed to occur in two major ways: (i) via direct interactions with cellular cascades yielding expression of neuroprotective and neuromodulatory proteins that promote neurogenesis, neuronal function and brain connectivity, and (ii) via blood-flow improvement and angiogenesis in the brain and sensory systems. Protective effects of long-term flavanol consumption on neurocognition and behavior, including age- and disease-related cognitive decline, were shown in animal models of normal aging, dementia, and stroke. A few human observational and intervention studies appear to corroborate these findings. Evidence on more immediate action of cocoa flavanols remains limited and inconclusive, but warrants further research. As an outline for future research on cocoa flavanol impact on human cognition, mood, and behavior, we underscore combination of functional neuroimaging with cognitive and behavioral measures of performance. PMID:23810791

  17. Cancer Protective Properties of Cocoa: A Review of the Epidemiologic Evidence

    Microsoft Academic Search

    Gertraud Maskarinec

    2009-01-01

    Due to their high concentration of catechins and procyanidins, bioactive compounds with distinct properties, cocoa and chocolate products may have beneficial health effects against oxidative stress and chronic inflammation, risk factors for cancer and other chronic diseases. This review focuses on the epidemiologic evidence for protective effects against cancer and overall mortality. The very small number of observational epidemiologic studies

  18. Modelling and experimental evaluation of high-pressure expression of cocoa nibs

    Microsoft Academic Search

    M. J. Venter; N. J. M. Kuipers; A. B. de Haan

    2007-01-01

    The ability of the Shirato model to describe the expression of dry cocoa nibs in a hydraulic press at pressures of 20–80MPa was compared with that of a numerically solved conservation laws model based on mass and momentum balances. Experimental data were used to determine the material constants involved in both models at 40, 80 and 100°C. The Shirato model

  19. Grading of Fermented and Dried Cocoa Beans Using Fungal Contamination, Ergosterol Index and Ochratoxin a Production

    PubMed Central

    Adegoke, G. O.; Varga, J.; Teren, J.

    2009-01-01

    Sixty four samples of cocoa beans replicated in quadruplicates were collected from five warehouses from southwest Nigeria and examined for fungal loads, ergosterol and ochratoxin A The levels of all the variables obtained were further used as indices for cocoa grading into food quality, FoQ (erg < 5 mg/kg; OTA < 1 µg/kg), feed quality, FeQ (erg = 5~10 mg/kg; OTA in the range of 1.1~3.11 µg/kg), Screen for mycotoxin, SFM (erg = 10~20 mg/kg; OTA from 3.12 µg/kg and above) with fuel quality, FuQ having erg > 20 mg/kg and OTA > 6.12 µg/kg. Using these ergosterol indices, 18.75% of the cocoa beans examined was classified with the FoQ, 18.75% with the FuQ while 31.25% was classified with both the FeQ and the SFM, respectively. In conclusion, ergosterol can be used as a rapid index to grade fermented, dried cocoa beans meant for export. PMID:23983536

  20. Tea, Coffee, and Cocoa as Ultraviolet Radiation Protectants for the Beet Armyworm Nucleopolyhedrovirus

    Microsoft Academic Search

    S. EL-SALAMOUNY; D. RANWALA; M. SHAPIRO; B. M. SHEPARD; ROBERT R. FARRAR

    The addition of 1% (wt:vol) aqueous extracts of cocoa (Theobroma cacao L.) (Malvales: Malvaceae), coffee (Coffea arabica L.) (Gentianales: Rubiaceae), and green and black tea (Camellia sinensis L.) (Ericales: Theaceae) provided excellent UV radiation protection for the beet armyworm, Spodoptera exigua (Hubner) (Lepidoptera: Noctuidae), nucleopolyhedrovirus under laboratory con- ditions. Aqueous extracts of coffee, green tea, and black tea at 0.5%

  1. Cocoa procyanidins with different degrees of polymerization possess distinct activities in models of colonic inflammation.

    PubMed

    Bitzer, Zachary T; Glisan, Shannon L; Dorenkott, Melanie R; Goodrich, Katheryn M; Ye, Liyun; O'Keefe, Sean F; Lambert, Joshua D; Neilson, Andrew P

    2015-08-01

    Procyanidins are available in the diet from sources such as cocoa and grapes. Procyanidins are unique in that they are comprised of repeating monomeric units and can exist in various degrees of polymerization. The degree of polymerization plays a role in determining the biological activities of procyanidins. However, generalizations cannot be made regarding the correlation between procyanidin structure and bioactivity because the size-activity relationship appears to be system dependent. Our aim was to screen fractions of procyanidins with differing degrees of polymerization in vitro for anti-inflammatory activities in models of colonic inflammation. Monomeric, oligomeric and polymeric cocoa procyanidin fractions were screened using cell models of disrupted membrane integrity and inflammation in human colon cells. High-molecular-weight polymeric procyanidins were the most effective at preserving membrane integrity and reducing secretion of interleukin-8 in response to inflammatory stimuli. Conversely, oligomeric procyanidins appeared to be the least effective. These results suggest that polymeric cocoa procyanidins may be the most effective for preventing loss of gut barrier function and epithelial inflammation, which are critical steps in the pathogenesis of metabolic endotoxemia, inflammatory bowel disease and colon cancer. Therefore, further investigations of the potential health-protective benefits of cocoa procyanidins with distinct degrees of polymerization, particularly high-molecular-weight procyanidins, are warranted. PMID:25869594

  2. Cocoa Growers' Bulletin No.52 November 2000 APPLICATION OF THE TECHNIQUES OF MOLECULAR BIOLOGY

    E-print Network

    Griffith, Gareth

    process. The most powerful of these tools are those of molecular biology, which permit direct analysis of molecular biology for each of these are described below Phytophthora Pod Rot (PPR), also widely knownCocoa Growers' Bulletin No.52 November 2000 - 46 - APPLICATION OF THE TECHNIQUES OF MOLECULAR

  3. The Cohort for Childhood Origin of Asthma and allergic diseases (COCOA) study: design, rationale and methods

    PubMed Central

    2014-01-01

    Background This paper describes the background, aim, and design of a prospective birth-cohort study in Korea called the COhort for Childhood Origin of Asthma and allergic diseases (COCOA). COCOA objectives are to investigate the individual and interactive effects of genetics, perinatal environment, maternal lifestyle, and psychosocial stress of mother and child on pediatric susceptibility to allergic diseases. Methods/Design The participants in COCOA represents a Korean inner-city population. Recruitment started on 19 November, 2007 and will continue until 31 December, 2015. Recruitment is performed at five medical centers and eight public-health centers for antenatal care located in Seoul. Participating mother-baby pairs are followed from before birth to adolescents. COCOA investigates whether the following five environmental variables contribute causally to the development and natural course of allergic diseases: (1) perinatal indoor factors (i.e. house-dust mite, bacterial endotoxin, tobacco smoking, and particulate matters 2.5 and 10), (2) perinatal outdoor pollutants, (3) maternal prenatal psychosocial stress and the child’s neurodevelopment, (4) perinatal nutrition, and (5) perinatal microbiome. Cord blood and blood samples from the child are used to assess whether the child’s genes and epigenetic changes influence allergic-disease susceptibility. Thus, COCOA aims to investigate the contributions of genetics, epigenetics, and various environmental factors in early life to allergic-disease susceptibility in later life. How these variables interact to shape allergic-disease susceptibility is also a key aim. The COCOA data collection schedule includes 11 routine standardized follow-up assessments of all children at 6 months and every year until 10 years of age, regardless of allergic-disease development. The mothers will complete multiple questionnaires to assess the baseline characteristics, the child’s exposure to environmental factors, maternal pre- and post-natal psychological stress, and the child’s neurodevelopment, nutritional status, and development of allergic and respiratory illnesses. The child’s microbiome, genes, epigenetics, plasma cytokine levels, and neuropsychological status, the microbiome of the residence, and the levels of indoor and outdoor pollutants are measured by standard procedures. Discussion The COCOA study will improve our understanding of how individual genetic or environmental risk factors influence susceptibility to allergic disease and how these variables interact to shape the phenotype of allergic diseases. PMID:24990471

  4. On-farm implementation of a starter culture for improved cocoa bean fermentation and its influence on the flavour of chocolates produced thereof.

    PubMed

    Lefeber, Timothy; Papalexandratou, Zoi; Gobert, William; Camu, Nicholas; De Vuyst, Luc

    2012-06-01

    Cocoa bean fermentations controlled by means of starter cultures were introduced on several farms in two different cocoa-producing regions (West Africa and Southeast Asia). Two starter culture mixtures were tested, namely one composed of Saccharomyces cerevisiae H5S5K23, Lactobacillus fermentum 222, and Acetobacter pasteurianus 386B (three heaps and one box), and another composed of L. fermentum 222 and A. pasteurianus 386B (seven heaps and one box). In all starter culture-added cocoa bean fermentation processes, the inoculated starter culture species were able to outgrow the natural contamination of the cocoa pulp-bean mass and they prevailed during cocoa bean fermentation. The application of both added starter cultures resulted in fermented dry cocoa beans that gave concomitant milk and dark chocolates with a reliable flavour, independent of cocoa-producing region or fermentation method. The addition of the lactic acid bacterium (LAB)/acetic acid bacterium (AAB) starter culture to the fermenting cocoa pulp-bean mass accelerated the cocoa bean fermentation process regarding citric acid conversion and lactic acid production through carbohydrate fermentation. For the production of a standard bulk chocolate, the addition of a yeast/LAB/AAB starter culture was necessary. This enabled an enhanced and consistent ethanol production by yeasts for a successful starter culture-added cocoa bean fermentation process. This study showed possibilities for the use of starter cultures in cocoa bean fermentation processing to achieve a reliably improved fermentation of cocoa pulp-bean mass that can consistently produce high-quality fermented dry cocoa beans and flavourful chocolates produced thereof. PMID:22365351

  5. Development of a quantitative PCR assay for rapid detection of Lactobacillus plantarum and Lactobacillus fermentum in cocoa bean fermentation.

    PubMed

    Schwendimann, Livia; Kauf, Peter; Fieseler, Lars; Gantenbein-Demarchi, Corinne; Miescher Schwenninger, Susanne

    2015-08-01

    To monitor dominant species of lactic acid bacteria during cocoa bean fermentation, i.e. Lactobacillus plantarum and Lactobacillus fermentum, a fast and reliable culture-independent qPCR assay was developed. A modified DNA isolation procedure using a commercial kit followed by two species-specific qPCR assays resulted in 100% sensitivity for L. plantarum and L. fermentum. Kruskal-Wallis and post-hoc analyses of data obtained from experiments with cocoa beans that were artificially spiked with decimal concentrations of L. plantarum and L. fermentum strains allowed the calculation of a regression line suitable for the estimation of both species with a detection limit of 3 to 4Logcells/g cocoa beans. This process was successfully tested for efficacy through the analyses of samples from laboratory-scale cocoa bean fermentations with both the qPCR assay and a culture-dependent method which resulted in comparable results. PMID:26026241

  6. Differences between the content of phenolic compounds in Criollo, Forastero and Trinitario cocoa seed ( Theobroma cacao L.)

    Microsoft Academic Search

    Silke Elwers; Alexis Zambrano; Christina Rohsius; Reinhard Lieberei

    2009-01-01

    Phenolic compounds contribute to the quality of raw cocoa, the basis of all chocolate products. Detailed research is needed\\u000a about the variability of these substances in unprocessed cocoa seed and during seed processing. For the present study, seed\\u000a samples of Upper Amazon Forastero, Lower Amazon Forastero, Nacional, Criollo and Trinitario from different origins were compared\\u000a in order to estimate the

  7. Chemical composition and physical quality characteristics of Ghanaian cocoa beans as affected by pulp pre-conditioning and fermentation

    Microsoft Academic Search

    Emmanuel Ohene Afoakwa; Jennifer Quao; Jemmy Takrama; Agnes Simpson Budu; Firibu Kwesi Saalia

    Investigations were conducted to evaluate the effects of pod storage (as a means of pulp preconditioning) and fermentation\\u000a on the chemical composition and physical characteristics of Ghanaian cocoa beans. A 4?×?2 full factorial design with factors\\u000a as pod storage (0, 7, 14, 21 days) and cocoa treatment (fermented and unfermented) were conducted. Samples were analyzed for\\u000a their chemical composition (moisture, crude

  8. Iowa Powder Atomization Technologies

    SciTech Connect

    None

    2012-01-01

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  9. Powder towpreg process development

    NASA Technical Reports Server (NTRS)

    Baucom, Robert M.; Marchello, Joseph M.

    1991-01-01

    The process for dry powder impregnation of carbon fiber tows being developed at LaRC overcomes many of the difficulties associated with melt, solution, and slurry prepregging. In the process, fluidized powder is deposited on spread tow bundles and fused to the fibers by radiant heating. Impregnated tows have been produced for preform, weaving, and composite materials applications. Design and operating data correlations were developed for scale up of the process to commercial operation. Bench scale single tow experiments at tow speeds up to 50 cm/sec have demonstrated that the process can be controlled to produce weavable towpreg. Samples were woven and molded into preform material of good quality.

  10. Detailed Analysis of the Microbial Population in Malaysian Spontaneous Cocoa Pulp Fermentations Reveals a Core and Variable Microbiota

    PubMed Central

    Mathawan, Melissa; Wittocx, Pieter-Jan; Saels, Veerle; Struyf, Nore; Bernaert, Herwig; Vrancken, Gino; Verstrepen, Kevin J.

    2013-01-01

    The fermentation of cocoa pulp is one of the few remaining large-scale spontaneous microbial processes in today's food industry. The microbiota involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production efficiency and cocoa quality. Despite intensive research in the field, a detailed and comprehensive analysis of the microbiota is still lacking, especially for the expanding Asian production region. Here, we report a large-scale, comprehensive analysis of four spontaneous Malaysian cocoa pulp fermentations across two time points in the harvest season and two fermentation methods. Our results show that the cocoa microbiota consists of a “core” and a “variable” part. The bacterial populations show a remarkable consistency, with only two dominant species, Lactobacillus fermentum and Acetobacter pasteurianus. The fungal diversity is much larger, with four dominant species occurring in all fermentations (“core” yeasts), and a large number of yeasts that only occur in lower numbers and specific fermentations (“variable” yeasts). Despite this diversity, a clear pattern emerges, with early dominance of apiculate yeasts and late dominance of Saccharomyces cerevisiae. Our results provide new insights into the microbial diversity in Malaysian cocoa pulp fermentations and pave the way for the selection of starter cultures to increase efficiency and consistency. PMID:24358116

  11. Detailed analysis of the microbial population in Malaysian spontaneous cocoa pulp fermentations reveals a core and variable microbiota.

    PubMed

    Meersman, Esther; Steensels, Jan; Mathawan, Melissa; Wittocx, Pieter-Jan; Saels, Veerle; Struyf, Nore; Bernaert, Herwig; Vrancken, Gino; Verstrepen, Kevin J

    2013-01-01

    The fermentation of cocoa pulp is one of the few remaining large-scale spontaneous microbial processes in today's food industry. The microbiota involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production efficiency and cocoa quality. Despite intensive research in the field, a detailed and comprehensive analysis of the microbiota is still lacking, especially for the expanding Asian production region. Here, we report a large-scale, comprehensive analysis of four spontaneous Malaysian cocoa pulp fermentations across two time points in the harvest season and two fermentation methods. Our results show that the cocoa microbiota consists of a "core" and a "variable" part. The bacterial populations show a remarkable consistency, with only two dominant species, Lactobacillus fermentum and Acetobacter pasteurianus. The fungal diversity is much larger, with four dominant species occurring in all fermentations ("core" yeasts), and a large number of yeasts that only occur in lower numbers and specific fermentations ("variable" yeasts). Despite this diversity, a clear pattern emerges, with early dominance of apiculate yeasts and late dominance of Saccharomyces cerevisiae. Our results provide new insights into the microbial diversity in Malaysian cocoa pulp fermentations and pave the way for the selection of starter cultures to increase efficiency and consistency. PMID:24358116

  12. Powder Cores s Molypermalloy

    E-print Network

    Software q Current Transformer Design Software q Inductor Design Software q Mag Amp Design Software POWDER.mag-inc.com PRODUCT LITERATURE AND DESIGN SOFTWARE CD CONTAINS q All Product Literature q Common Mode FIlter Design the Proper Core for Saturating Transformers q TWC-S3 Inverter Transformer Core Design and Material Selection

  13. Demystifying Mystery Powders.

    ERIC Educational Resources Information Center

    Kotar, Michael

    1989-01-01

    Describes science activities which use simple chemical tests to distinguish between materials and to determine some of their properties. Explains the water, iodine, heat, acid, baking soda, acid/base indicator, glucose, and sugar tests. Includes activities to enhance chemical testing and a list of suggested powders for use. (RT)

  14. Analysis of cocoa flavanols and procyanidins (DP 1-10) in cocoa-containing ingredients and products by rapid resolution liquid chromatography: single-laboratory validation.

    PubMed

    Machonis, Philip R; Jones, Matthew A; Kwik-Uribe, Catherine

    2014-01-01

    Recently, a multilaboratory validation (MLV) of AOAC Official Method 2012.24 for the determination of cocoa flavanols and procyanidins (CF-CP) in cocoa-based ingredients and products determined that the method was robust, reliable, and transferrable. Due to the complexity of the CF-CP molecules, this method required a run time exceeding 1 h to achieve acceptable separations. To address this issue, a rapid resolution normal phase LC method was developed, and a single-laboratory validation (SLV) study conducted. Flavanols and procyanidins with a degree of polymerization (DP) up to 10 were eluted in 15 min using a binary gradient applied to a diol stationary phase, detected using fluorescence detection, and reported as a total sum of DP 1-10. Quantification was achieved using (-)-epicatechin-based relative response factors for DP 2-10. Spike recovery samples and seven different types of cocoa-based samples were analyzed to evaluate the accuracy, precision, LOD, LOQ, and linearity of the method. The within-day precision of the reported content for the samples was 1.15-5.08%, and overall precision was 3.97-13.61%. Spike-recovery experiments demonstrated recoveries of over 98%. The results of this SLV were compared to those previously obtained in the MLV and found to be consistent. The translation to rapid resolution LC allowed for an 80% reduction in analysis time and solvent usage, while retaining the accuracy and reliability of the original method. The savings in both cost and time of this rapid method make it well-suited for routine laboratory use. PMID:24672873

  15. Cocoa, Hazelnuts, Sterols and Soluble Fiber Cream Reduces Lipids and Inflammation Biomarkers in Hypertensive Patients: A Randomized Controlled Trial

    PubMed Central

    Solà, Rosa; Valls, Rosa M.; Godàs, Gemma; Perez-Busquets, Gloria; Ribalta, Josep; Girona, Josefa; Heras, Mercedes; Cabré, Anna; Castro, Antoni; Domenech, Gema; Torres, Ferran; Masana, Lluís; Anglés, Neus; Reguant, Jordi; Ramírez, Bartolomé; Barriach, Joaquim M.

    2012-01-01

    Background Cocoa, mixed with other food ingredients, intake can have beneficial effects on cardiovascular disease (CVD) biomarkers. We compared the effects of 4 cocoa cream products on some of these biomarkers. Methods and Findings In this multi-centered, randomized, controlled, double-blind, parallel trial, volunteers (n?=?113; age range: 43–65 years) who were pre-hypertensive, stage-1 hypertensive and hypercholesterolemic received one of 4 cocoa cream products (13 g/unit; 1 g cocoa/unit, 6 units/d; 465 Kcal/d) added to a low saturated fat diet for 4 weeks. The groups were: A) (n?=?28), cocoa cream considered as control; B) (n?=?28), cocoa+hazelnut cream (30 g/d hazelnuts); C) (n?=?30), cocoa+hazelnuts+phytosterols (2 g/d); and D) (n?=?27), cocoa+hazelnuts+phytosterols+soluble fiber (20 g/d) the patented “LMN product”. Primary outcome measures were BP, LDL-c, apolipoprotein B-100 (Apo B), ApoB/ApoA ratio, oxidized LDL (oxLDL) and high-sensitive C-reactive protein (hsCRP) determined at baseline and post-cocoa cream product intake. Statistical analysis used was ANCOVA or mixed models (in case of repeated measurements), with baseline observation included as a covariate. After 4 weeks, compared to product A, product C reduced LDL-c by 11.2%, Apo B by 8.1% and ApoB/ApoA ratio by 7.8% (P?=?0.01). LMN decreased LDL-c by 9.2%, Apo B-100 by 8.5%, ApoB/ApoA ratio by 10.5%, hsCRP by 33.4% and oxLDL by 5.9% (P?=?0.01). Surprisingly, even “control” product A reduced systolic BP (?7.89 mmHg; 95%CI: ?11.45 to ?4.3) and diastolic BP (?5.54 mmHg; 95%CI: ?7.79 to ?3.29). The BP reductions were similar with the other 3 products. Limitations of the study are that the trial period was relatively short and that a better “BP control” product would have been preferable. Conclusion The creams (particularly the LMN) have anti-inflammatory and antioxidant effects in addition to lowering LDL-c, Apo B and ApoB/ApoA ratio. Thus, the soluble fiber effects amplified with sterols (as contained in the cocoa creams) provide new dietary therapeutic perspectives. Trial Registration Clinicaltrials.gov NCT00511420 PMID:22383996

  16. Tea, coffee, and cocoa as ultraviolet radiation protectants for the beet armyworm nucleopolyhedrovirus.

    PubMed

    El-Salamouny, S; Ranwala, D; Shapiro, M; Shepard, B M; Farrar, Robert R

    2009-10-01

    The addition of 1% (wt:vol) aqueous extracts of cocoa (Theobroma cacao L.) (Malvales: Malvaceae), coffee (Coffea arabica L.) (Gentianales: Rubiaceae), and green and black tea (Camellia sinensis L.) (Ericales: Theaceae) provided excellent UV radiation protection for the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), nucleopolyhedrovirus under laboratory conditions. Aqueous extracts of coffee, green tea, and black tea at 0.5% provided 85-100% UV protection, whereas cocoa provided 50% UV protection. Epigallocatechin gallate (EGCG), a component of green tea, and caffeine, a component of tea and coffee, also were tested as UV protectants. Both compounds were ineffective when tested alone. When EGCG and caffeine were combined, UV protection increased in a synergistic manner, but <35% of the original virus activity was maintained. This study demonstrated that coffee was comparable to green tea and black tea as a UV protectant. Further studies should be conducted to optimize their use in biopesticide formulations. PMID:19886440

  17. Regular consumption of a cocoa product improves the cardiometabolic profile in healthy and moderately hypercholesterolaemic adults.

    PubMed

    Sarriá, Beatriz; Martínez-López, Sara; Sierra-Cinos, José Luis; García-Diz, Luis; Mateos, Raquel; Bravo, Laura

    2014-01-14

    Cocoa products present great health potential due to their high content of polyphenols, mainly of flavanols. However, the antioxidant, anti-inflammatory and other health effects of regularly consuming cocoa products seem to depend on the intake and health status of the consumer, etc. and need to be further clarified. A randomised, controlled, cross-over, free-living study was carried out in healthy (n 24) and moderately hypercholesterolaemic (>2000 mg/l, n 20) subjects to assess the influence of regularly consuming (4 weeks) two servings (15 g each) of a cocoa product rich in fibre (containing 33·9 % of total dietary fibre (TDF) and 13·9 mg/g of soluble polyphenols) in milk v. consuming only milk (control) on (1) serum lipid and lipoprotein profile, (2) serum malondialdehyde levels, carbonyl groups, ferric reducing/antioxidant power, oxygen radical absorbance capacity and free radical-scavenging capacity, (3) IL-1?, IL-6, TNF-?, IL-10, IL-8, monocyte chemoattractant protein-1, and vascular and intracellular cell adhesion molecule levels, and (4) systolic and diastolic blood pressure and heart rate. Throughout the study, the diet and physical activity of the volunteers, as well as any possible changes in weight or other anthropometric parameters, were also evaluated. The intake of TDF increased (P< 0·001) to the recommended levels. Serum HDL-cholesterol (HDL-C) levels were increased (P< 0·001), whereas glucose (P= 0·029), IL-1? (P= 0·001) and IL-10 (P= 0·001) levels were decreased. The rest of the studied cardiovascular parameters, as well as the anthropometric ones, remained similar. In conclusion, regularly consuming a cocoa product with milk improves cardiovascular health by increasing HDL-C levels and inducing hypoglycaemic and anti-inflammatory effects in healthy and hypercholesterolaemic individuals without causing weight gain. PMID:23823716

  18. A Cocoa Peptide Protects Caenorhabditis elegans from Oxidative Stress and ?-Amyloid Peptide Toxicity

    PubMed Central

    Martorell, Patricia; Bataller, Esther; Llopis, Silvia; Gonzalez, Núria; Álvarez, Beatriz; Montón, Fernando; Ortiz, Pepa; Ramón, Daniel; Genovés, Salvador

    2013-01-01

    Background Cocoa and cocoa-based products contain different compounds with beneficial properties for human health. Polyphenols are the most frequently studied, and display antioxidant properties. Moreover, protein content is a very interesting source of antioxidant bioactive peptides, which can be used therapeutically for the prevention of age-related diseases. Methodology/Principal Findings A bioactive peptide, 13L (DNYDNSAGKWWVT), was obtained from a hydrolyzed cocoa by-product by chromatography. The in vitro inhibition of prolyl endopeptidase (PEP) was used as screening method to select the suitable fraction for peptide identification. Functional analysis of 13L peptide was achieved using the transgenic Caenorhabditis elegans strain CL4176 expressing the human A?1–42 peptide as a pre-clinical in vivo model for Alzheimer's disease. Among the peptides isolated, peptide 13L (1 µg/mL) showed the highest antioxidant activity (P?0.001) in the wild-type strain (N2). Furthermore, 13L produced a significant delay in body paralysis in strain CL4176, especially in the 24–47 h period after A?1–42 peptide induction (P?0.0001). This observation is in accordance with the reduction of A? deposits in CL4176 by western blot. Finally, transcriptomic analysis in wild-type nematodes treated with 13L revealed modulation of the proteosomal and synaptic functions as the main metabolic targets of the peptide. Conclusions/Significance These findings suggest that the cocoa 13L peptide has antioxidant activity and may reduce A? deposition in a C. elegans model of Alzheimer's disease; and therefore has a putative therapeutic potential for prevention of age-related diseases. Further studies in murine models and humans will be essential to analyze the effectiveness of the 13L peptide in higher animals. PMID:23675471

  19. The effect of shear rate, temperature, sugar and emulsifier on the tempering of cocoa butter

    Microsoft Academic Search

    D. Dhonsi; A. G. F. Stapley

    2006-01-01

    The influence of shear rate and temperature on the tempering of different mixtures of cocoa butter, sugar and lecithin has been studied using a concentric cylinder viscometer as a shearing device and using viscosity measurement to monitor crystallization. Shear rates ranging from 1 to 50s?1 were tested at four different isothermal temperatures (13°C, 17°C, 20°C and 23°C). Three different material

  20. Early growth and nutritional response to resource competition in cocoa-shade intercropped systems

    Microsoft Academic Search

    M. E. Isaac; F. Ulzen-Appiah; V. R. Timmer; S. J. Quashie-Sam

    2007-01-01

    Intercropping is often promoted for effective mutualism between species, thus compensating for external inputs. However, for\\u000a optimal farm design resulting in superior production and nutrition, an accurate assessment of plant inter- and intra-specific\\u000a competition is required. In predominant shade tree-cocoa (Theobroma cacao) systems, inconclusive evidence remains on species interactions, limitations to resource availability and subsequent growth\\u000a and nutritional response, particularly

  1. Triglyceride interesterification by lipases. 1. Cocoa butter equivalents from a fraction of palm oil

    Microsoft Academic Search

    Scott Bloomer; Patrick Adlercreutz; Bo Mattiasson

    1990-01-01

    Twelve commercially available triacylglycerol lipase preparations were screened for their suitability as catalysts in the\\u000a interesterification of palm oil mid fraction and ethyl stearate to form a cocoa butter equivalent. Five fungal lipase preparations\\u000a were found to be suitable. The hydrolytic activity of the commercial lipase preparations was tested with sunflower seed oil\\u000a and was independent of their interesterification activity.

  2. Antioxidant and antilisterial activity of olive oil, cocoa and rosemary extract polyphenols

    Microsoft Academic Search

    Marina Bubonja-Sonje; Jasminka Giacometti; Maja Abram

    2011-01-01

    Antibacterial and antioxidant activity of polyphenols from olive oil, cocoa, and rosemary extract was tested. Antimicrobial activity against Listeria strains was assessed using broth dilution and time-kill curve methods. The 2,2-diphenyl-2-picrylhydracyl hydrate (DPPH) radical scavenging method, Folin–Ciocalteu method, and high performance liquid chromatography (HPLC) were used for phenolics identification and determination of antioxidants level. Antibacterial and antioxidant activity of main

  3. Original article Elaboration of a fruit wine from cocoa (Theobroma cacao L.) pulp

    Microsoft Academic Search

    Disney Ribeiro Dias; Rosane Freitas Schwan; Evandro Sena Freire; Rogerio dos Santos Serodio

    2007-01-01

    Summary The objectives of this study were the selection of a strain of Saccharomyces cerevisiae, the elaboration of a fermentative process using cocoa (Theobroma cacao L.) fruit pulp, and the assessment of the acceptance of the elaborated beverage. Three S. cerevisiae strains (CA116, CA1162 and CA1183) were assessed while growing in a fruit pulp medium at different temperatures. The ethanol:biomass

  4. Efficacy of Trichoderma asperellum oil formulations on the control of cocoa black pod disease (Phytophthora megakarya).

    PubMed

    Mbarga, J B; Ten Hoopen, G Martijn; Begoude, A D; Tondje, P R; Kuate, J; Ambang, Z; Amougou, A; Schiffers, B

    2012-01-01

    The objective of this study was therefore to develop a formulation of conidia of T. asperellum with the aim of improving its efficacy. The formulations developed were oily dispersions. It was a combination of solvents consisting of groundnut oil or palm oil with structural agents and emulsifying-dispersing agents. Emulsification tests were carried out and the stability of the emulsions evaluated. The evaluation of the effect of co-formulants on the growth of conidia of T. asperellum was done by reading the optical densities of the formulated samples on multi-plates using a plate reader. The test on detached cocoa pods was done by treating the cocoa pods with selected formulations at 1.10(7) conidia/ml and inoculation of the treated cocoa pods was done 24 hours later with zoospores of P. megakarya at 1.10(5) zoospores/ml. The growth of necrosis on the fruits was measured daily. The screening of co-formulants and emulsification tests ended up with the selection of two formulations. The first composed of conidia of T. asperellum, groundnut oil, Tensiofix NTM and Tensiofix 869. The second differed from the first by utilisation of palm oil as the solvent. These formulations proved stable when diluted in water with 1% and 0.5% of sedimentation respectively after 24 hours. The viability test of the conidia indicated that the different formulations selected did not have a fungitoxic effect. The test on detached cocoa pods showed an improved efficacy of T. asperellum to control the disease. The growth rates of necrosis were 6.29 mm/day, 7.25 mm/day and 31.6 mm/day for treatment with formulation 1, pure conidia and control treated with water respectively. PMID:23878961

  5. Powder characteristics and coating conditions of fresh and reused polyester resins for electrostatic powder coating: powder recycling and loss prevention

    Microsoft Academic Search

    A. W. Lothongkum; R. Nonthapone; K. Seangkiatiyuth; W. Tanthapanichkoon

    2007-01-01

    Powder characteristics and coating conditions are significant factors in electrostatic powder coating. In this work, powder characteristics of the reused polyester resin or recycled powder particles in terms of shape, size, particle size distribution, moisture content, density, flowability, fluidity and chargeability were compared with those of fresh resin or as-received powder to consider powder recycling. The coating conditions for a

  6. Cocoa bean quality assessment by using hyperspectral images and fuzzy logic techniques

    NASA Astrophysics Data System (ADS)

    Soto, Juan; Granda, Guillermo; Prieto, Flavio; Ipanaque, William; Machacuay, Jorge

    2015-04-01

    Nowadays, cocoa bean exportation from Piura-Peru is having a positive international market response due to their inherent high quality. Nevertheless, when using subjective techniques for quality assessment, such as the cut test, a wastefulness of grains is generated, additional to a restriction in the selection as well as improvement approaches in earlier stages for optimizing the quality. Thus, in an attempt to standardize the internal features analyzed by the cut test, for instance, crack formation and internal color changes during the fermentation, this research is submitted as an approach which aims to make use of hyperspectral images, with the purpose of having a quick and accurate analysis. Hyperspectral cube size was reduced by using Principal Component Analysis (PCA). The image generated by principal component PC1 provides enough information to clearly distinguish the internal cracks of the cocoa bean, since the zones where these cracks are, have a negative correlation with PC1. The features taken were processed through a fuzzy block, which is able to describe the cocoa bean quality. Three membership functions were defined in the output: unfermented, partly fermented and well fermented, by using trapezoidal-shaped and triangular-shaped functions. A total of twelve rules were propounded. Furthermore, the bisector method was chosen for the defuzzification. Begin the abstract two lines below author names and addresses.

  7. Influence of Fermentation and Drying Materials on the Contamination of Cocoa Beans by Ochratoxin A

    PubMed Central

    Dano, Sébastien Djédjé; Manda, Pierre; Dembélé, Ardjourma; Abla, Ange Marie-Joseph Kouassi; Bibaud, Joel Henri; Gouet, Julien Zroh; Sika, Charles Bruno Ze Maria

    2013-01-01

    Ochratoxin A (OTA) is a mycotoxin produced mainly by species of Aspergillus and Penicillium. Contamination of food with OTA is a major consumer health hazard. In Côte d’Ivoire, preventing OTA contamination has been the subject of extensive study. The current study was conducted to evaluate the influence of fermentation and drying materials on the OTA content in cocoa. For each test, 7000 intact cocoa pods were collected, split open to remove the beans, fermented using 1 of 3 different materials, sun-dried on 1 of 3 different platform types and stored for 30 days. A total of 22 samples were collected at each stage of post-harvesting operations. The OTA content in the extracted samples was then quantified by high-performance liquid chromatography. OTA was detected in beans at all stages of post-harvesting operations at varying levels: pod-opening (0.025 ± 0.02 mg/kg), fermentation (0.275 ± 0.2 mg/kg), drying (0.569 ± 0.015 mg/kg), and storage (0.558 ± 0.04 mg/kg). No significant relationships between the detected OTA level and the materials used in the fermentation and drying of cocoa were observed. PMID:24287569

  8. Evaluation of high oleic-high stearic sunflower hard stearins for cocoa butter equivalent formulation.

    PubMed

    Bootello, Miguel A; Hartel, Richard W; Garcés, Rafael; Martínez-Force, Enrique; Salas, Joaquín J

    2012-10-01

    Cocoa butter equivalents (CBEs) are produced from vegetable fats by blending palm mid fraction (PMF) and tropical butters coming from shea, mango kernel or kokum fat. In this regard, high oleic-high stearic (HOHS) sunflower hard stearins from solvent fractionation can be used in CBE production since their compositions and physical properties are similar to those found in the above-mentioned tropical butters. In this work, three sunflower hard stearins (SHS) ranging from 65% to 95% of disaturated triacylglycerols and a shea stearin (used as reference) were blended with PMF to evaluate their potential use in CBEs formulation. Isosolid phase diagrams of mixtures of PMF/SHS showed eutectic formation for SHS 65 and SHS 80, but monotectic behaviour with softening effect for SHS 95. Three CBEs from SHS and shea stearin were formulated according to phase behaviour diagrams and solid fat content data at 25 °C. Isosolid phase diagrams of mixtures of these CBEs with cocoa butter showed no eutectic behaviour. Therefore, CBEs elaborated from SHS exhibited full compatibility with cocoa butter. PMID:25005960

  9. Cocoa Enriched Diets Enhance Expression of Phosphatases and Decrease Expression of Inflammatory Molecules in Trigeminal Ganglion Neurons

    PubMed Central

    Cady, Ryan J.; Durham, Paul L.

    2010-01-01

    Activation of trigeminal nerves and release of neuropeptides that promote inflammation are implicated in the underlying pathology of migraine and temporomandibular joint (TMJ) disorders. The overall response of trigeminal nerves to peripheral inflammatory stimuli involves a balance between enzymes that promote inflammation, kinases, and those that restore homeostasis, phosphatases. The goal of this study was to determine the effects of a cocoa-enriched diet on the expression of key inflammatory proteins in trigeminal ganglion neurons under basal and inflammatory conditions. Rats were fed a control diet or an isocaloric diet enriched in cocoa for 14 days prior to an injection of noxious stimuli to cause acute or chronic excitation of trigeminal neurons. In animals fed a cocoa-enriched diet, basal levels of the mitogen-activated kinase (MAP) phosphatases MKP-1 and MKP-3 were elevated in neurons. Importantly, the stimulatory effects of acute or chronic peripheral inflammation on neuronal expression of the MAPK p38 and extracellular signal-regulated kinases (ERK) were significantly repressed in response to cocoa. Similarly, dietary cocoa significantly suppressed basal neuronal expression of calcitonin gene-related peptide (CGRP) as well as stimulated levels of the inducible form of nitric oxide synthase (iNOS), proteins implicated in the underlying pathology of migraine and TMJ disorders. To our knowledge, this is first evidence that a dietary supplement can cause upregulation of MKP, and that cocoa can prevent inflammatory responses in trigeminal ganglion neurons. Furthermore, our data provide evidence that cocoa contains biologically active compounds that would be beneficial in the treatment of migraine and TMJ disorders. PMID:20138852

  10. Processing polymeric powders

    NASA Technical Reports Server (NTRS)

    Throne, James L.

    1989-01-01

    The concept of uniformly and continuously depositing and sinter-fusing nominal 0.1 to 40 microns dimensioned electrostatically charged polymer powder particles onto essentially uniformly spread 5 to 20 micron grounded continuous fiber tow to produce a respoolable thermoplastic composite two-preg was formulated at NASA Langley. The process was reduced to practice under a NASA grant at the University of Akron this spring. The production of tow-preg is called phase 1. The production of ultrafine polymer powders from 5 to 10 percent (wt) polymer solids in solvent is considered. This is phase 0 and is discussed. The production of unitape from multi tow-pregs was also considered. This is phase 2 and is also discussed. And another approach to phase 1, also proposed last summer, was scoped. This is phase 1A and is also discussed.

  11. Fluidised powder as a new target technology

    E-print Network

    McDonald, Kirk

    : scope for a rig #12;Powder jet test plant layout Compressed air supplyVacuum/air powder #12;Powder jet/w solid to air ratio is not good enough!) · How does a dense, dense powder jet behave like? Preliminary tests at Gericke ltd #12;AIR/PRESSURE IN POWDER IN JET GENERATION AIR EXTRACTION POWDER OUT DENSE

  12. Towards the understanding of the cocoa transcriptome: Production and analysis of an exhaustive dataset of ESTs of Theobroma cacao L. generated from various tissues and under various conditions.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Theobroma cacao L., is a tree originated from the tropical rainforest of South America. It is one of the major cash crops for many tropical countries. Cocoa is mainly produced on small holdings, providing resources for 14 million farmers. Disease resistance and cocoa quality improvement are two impo...

  13. The Key to Acetate: Metabolic Fluxes of Acetic Acid Bacteria under Cocoa Pulp Fermentation-Simulating Conditions

    PubMed Central

    Adler, Philipp; Frey, Lasse Jannis; Berger, Antje; Bolten, Christoph Josef; Hansen, Carl Erik

    2014-01-01

    Acetic acid bacteria (AAB) play an important role during cocoa fermentation, as their main product, acetate, is a major driver for the development of the desired cocoa flavors. Here, we investigated the specialized metabolism of these bacteria under cocoa pulp fermentation-simulating conditions. A carefully designed combination of parallel 13C isotope labeling experiments allowed the elucidation of intracellular fluxes in the complex environment of cocoa pulp, when lactate and ethanol were included as primary substrates among undefined ingredients. We demonstrate that AAB exhibit a functionally separated metabolism during coconsumption of two-carbon and three-carbon substrates. Acetate is almost exclusively derived from ethanol, while lactate serves for the formation of acetoin and biomass building blocks. Although this is suboptimal for cellular energetics, this allows maximized growth and conversion rates. The functional separation results from a lack of phosphoenolpyruvate carboxykinase and malic enzymes, typically present in bacteria to interconnect metabolism. In fact, gluconeogenesis is driven by pyruvate phosphate dikinase. Consequently, a balanced ratio of lactate and ethanol is important for the optimum performance of AAB. As lactate and ethanol are individually supplied by lactic acid bacteria and yeasts during the initial phase of cocoa fermentation, respectively, this underlines the importance of a well-balanced microbial consortium for a successful fermentation process. Indeed, AAB performed the best and produced the largest amounts of acetate in mixed culture experiments when lactic acid bacteria and yeasts were both present. PMID:24837393

  14. The key to acetate: metabolic fluxes of acetic acid bacteria under cocoa pulp fermentation-simulating conditions.

    PubMed

    Adler, Philipp; Frey, Lasse Jannis; Berger, Antje; Bolten, Christoph Josef; Hansen, Carl Erik; Wittmann, Christoph

    2014-08-01

    Acetic acid bacteria (AAB) play an important role during cocoa fermentation, as their main product, acetate, is a major driver for the development of the desired cocoa flavors. Here, we investigated the specialized metabolism of these bacteria under cocoa pulp fermentation-simulating conditions. A carefully designed combination of parallel 13C isotope labeling experiments allowed the elucidation of intracellular fluxes in the complex environment of cocoa pulp, when lactate and ethanol were included as primary substrates among undefined ingredients. We demonstrate that AAB exhibit a functionally separated metabolism during coconsumption of two-carbon and three-carbon substrates. Acetate is almost exclusively derived from ethanol, while lactate serves for the formation of acetoin and biomass building blocks. Although this is suboptimal for cellular energetics, this allows maximized growth and conversion rates. The functional separation results from a lack of phosphoenolpyruvate carboxykinase and malic enzymes, typically present in bacteria to interconnect metabolism. In fact, gluconeogenesis is driven by pyruvate phosphate dikinase. Consequently, a balanced ratio of lactate and ethanol is important for the optimum performance of AAB. As lactate and ethanol are individually supplied by lactic acid bacteria and yeasts during the initial phase of cocoa fermentation, respectively, this underlines the importance of a well-balanced microbial consortium for a successful fermentation process. Indeed, AAB performed the best and produced the largest amounts of acetate in mixed culture experiments when lactic acid bacteria and yeasts were both present. PMID:24837393

  15. Sintering of powder mixtures and the growth of ferrous powder metallurgy

    Microsoft Academic Search

    K. S Narasimhan

    2001-01-01

    Advances in the understanding of sintering of powder mixtures contributed significantly to the growth of ferrous powder metallurgy industry. Solid-state sintering and liquid-phase activated sintering play an important role in the sintering of powder mixtures. In this paper, sintering of iron powder with graphite; iron powder with copper and graphite; iron powder with nickel and graphite; iron powder with phosphorus;

  16. Comminution of stainless steel powders

    Microsoft Academic Search

    B. A. Borok; R. P. Schchegoleva; L. S. Golubeva; F. S. Sariadi; E. M. Rabinovich

    1974-01-01

    1.Atmospheric milling in barrel type mixers at a powder-to-ball weight ratio of 1::2 is an effective means of comminuting stainless steel powders produced by the coreduction process. In the work described, milling for 27 h was found to increase the amount of the -0.063-mm fraction from ~15 to ~75% for a Kh18N15 steel powder and from ~24.6 to ~70%for a

  17. Species Diversity, Community Dynamics, and Metabolite Kinetics of the Microbiota Associated with Traditional Ecuadorian Spontaneous Cocoa Bean Fermentations?

    PubMed Central

    Papalexandratou, Zoi; Falony, Gwen; Romanens, Edwina; Jimenez, Juan Carlos; Amores, Freddy; Daniel, Heide-Marie; De Vuyst, Luc

    2011-01-01

    Traditional fermentations of the local Ecuadorian cocoa type Nacional, with its fine flavor, are carried out in boxes and on platforms for a short time. A multiphasic approach, encompassing culture-dependent and -independent microbiological analyses of fermenting cocoa pulp-bean samples, metabolite target analyses of both cocoa pulp and beans, and sensory analysis of chocolates produced from the respective fermented dry beans, was applied for the investigation of the influence of these fermentation practices on the yeast and bacterial species diversity and community dynamics during cocoa bean fermentation. A wide microbial species diversity was found during the first 3 days of all fermentations carried out. The prevailing ethanol-producing yeast species were Pichia kudriavzevii and Pichia manshurica, followed by Saccharomyces cerevisiae. Leuconostoc pseudomesenteroides (glucose and fructose fermenting), Fructobacillus tropaeoli-like (fructose fermenting), and Lactobacillus fermentum (citrate converting, mannitol producing) represented the main lactic acid bacterial species in the fermentations studied, resulting in intensive heterolactate metabolism of the pulp substrates. Tatumella saanichensis and Tatumella punctata were among the members of the family Enterobacteriaceae present during the initial phase of the cocoa bean fermentations and could be responsible for the production of gluconic acid in some cases. Also, a potential new yeast species was isolated, namely, Candida sorbosivorans-like. Acetic acid bacteria, whose main representative was Acetobacter pasteurianus, generally appeared later during fermentation and oxidized ethanol to acetic acid. However, acetic acid bacteria were not always present during the main course of the platform fermentations. All of the data taken together indicated that short box and platform fermentation methods caused incomplete fermentation, which had a serious impact on the quality of the fermented dry cocoa beans. PMID:21926224

  18. Isolation and characterization of 2S cocoa seed albumin storage polypeptide and the corresponding cDNA.

    PubMed

    Kochhar, S; Gartenmann, K; Guilloteau, M; McCarthy, J

    2001-09-01

    The amine pool of cocoa is known to be an essential component for the development of the typical cocoa flavor. To better understand and to produce an intense in vitro cocoa flavor, identification of the polypeptides that are the source of the amine flavor precursor pool is essential. Chromatographic analysis of the polypeptide profile of unfermented cocoa resulted in identification of a novel storage polypeptide of M(r) 8515. The N-terminal sequence of the first 34 residues of the purified polypeptide shows similarity to 2S storage albumins of cotton and Brazil nut and sweet protein, Mabinlin. To identify the corresponding cDNA of the putative cocoa 2S albumin, 18 randomly chosen clones from the cDNA library of immature Theobroma cacao seed mRNA were sequenced, and a full-length cDNA clone encoding a protein harboring the N-terminal sequence of the novel polypeptide was selected. The open reading frame of the clone encodes a polypeptide of M(r) 17125. Comparison of the translated amino acid sequence of the precursor protein or the mature polypeptide against the Swiss-Prot and TrEMBL databases shows high sequence similarity (>52%) and identity (>38%) to many plant 2S albumins. Tryptic peptide mass fingerprinting of the purified polypeptide by high-performance liquid chromatography-electrospray ionization mass spectrometry shows 10 masses that match the expected tryptic peptides of the deduced sequence. Together with the published work on plant 2S albumin processing, the results presented here suggest that post-translational processing yields a 73-residue polypeptide (residue positions 78-150) corresponding to the 9 kDa subunit of the mature cocoa 2S albumin protein. PMID:11559156

  19. The effect of cocoa supplementation on hepatic steatosis, reactive oxygen species and LFABP in a rat model of NASH

    PubMed Central

    2011-01-01

    Background Non alcoholic steatohepatitis is hypothesised to develop via a mechanism involving fat accumulation and oxidative stress. The current study aimed to investigate if an increase in oxidative stress was associated with changes in the expression of liver fatty acid binding protein in a rat model of non alcoholic steatohepatitis and whether cocoa supplementation attenuated those changes. Methods Female Sprague Dawley rats were fed a high fat control diet, a high fat methionine choline deficient diet, or one of four 12.5% cocoa supplementation regimes in combination with the high fat methionine choline deficient diet. Results Liver fatty acid binding protein mRNA and protein levels were reduced in the liver of animals with fatty liver disease when compared to controls. Increased hepatic fat content was accompanied by higher levels of oxidative stress in animals with fatty liver disease when compared to controls. An inverse association was found between the levels of hepatic liver fatty acid binding protein and the level of hepatic oxidative stress in fatty liver disease. Elevated NADPH oxidase protein levels were detected in the liver of animals with increased severity in inflammation and fibrosis. Cocoa supplementation was associated with partial attenuation of these pathological changes, although the severity of liver disease induced by the methionine choline deficient diet prevented complete reversal of any disease associated changes. Red blood cell glutathione was increased by cocoa supplementation, whereas liver glutathione was reduced by cocoa compared to methionine choline deficient diet fed animals. Conclusion These findings suggest a potential role for liver fatty acid binding protein and NADPH oxidase in the development of non alcoholic steatohepatitis. Furthermore, cocoa supplementation may have be of therapeutic benefit in less sever forms of NASH. PMID:22081873

  20. Seeding effects on solidification behavior of cocoa butter and dark chocolate. II. Physical properties of dark chocolate

    Microsoft Academic Search

    Iwao Hachiya; Tetsuo Koyano; Kiyotaka Sato

    1989-01-01

    Demolding property just after solidification, we examined the polymorphism of cocoa butter in seed-solidified dark chocolate\\u000a and fat-bloom stability through two thermocycle tests between 38 and 20°C (38\\/20) and between 32 and 20°C (32\\/20). The seed\\u000a crystals employed are Form VI of cocoa butter,?\\u000a 1 of SOS (1,3-distearoyl-2-oleoyl-glycerol), pseudo-?’ and?\\u000a 2 of BOB (1,3-dibehenoyl-2-oleoylglycerol) and ? of SSS (1,2,3-tristearoylglycerol). The

  1. Core Fluxome and Metafluxome of Lactic Acid Bacteria under Simulated Cocoa Pulp Fermentation Conditions

    PubMed Central

    Adler, Philipp; Bolten, Christoph Josef; Dohnt, Katrin; Hansen, Carl Erik

    2013-01-01

    In the present work, simulated cocoa fermentation was investigated at the level of metabolic pathway fluxes (fluxome) of lactic acid bacteria (LAB), which are typically found in the microbial consortium known to convert nutrients from the cocoa pulp into organic acids. A comprehensive 13C labeling approach allowed to quantify carbon fluxes during simulated cocoa fermentation by (i) parallel 13C studies with [13C6]glucose, [1,2-13C2]glucose, and [13C6]fructose, respectively, (ii) gas chromatography-mass spectrometry (GC/MS) analysis of secreted acetate and lactate, (iii) stoichiometric profiling, and (iv) isotopomer modeling for flux calculation. The study of several strains of L. fermentum and L. plantarum revealed major differences in their fluxes. The L. fermentum strains channeled only a small amount (4 to 6%) of fructose into central metabolism, i.e., the phosphoketolase pathway, whereas only L. fermentum NCC 575 used fructose to form mannitol. In contrast, L. plantarum strains exhibited a high glycolytic flux. All strains differed in acetate flux, which originated from fractions of citrate (25 to 80%) and corresponding amounts of glucose and fructose. Subsequent, metafluxome studies with consortia of different L. fermentum and L. plantarum strains indicated a dominant (96%) contribution of L. fermentum NCC 575 to the overall flux in the microbial community, a scenario that was not observed for the other strains. This highlights the idea that individual LAB strains vary in their metabolic contribution to the overall fermentation process and opens up new routes toward streamlined starter cultures. L. fermentum NCC 575 might be one candidate due to its superior performance in flux activity. PMID:23851099

  2. Occurrence and diversity of yeasts involved in fermentation of West African cocoa beans.

    PubMed

    Jespersen, Lene; Nielsen, Dennis S; Hønholt, Susanne; Jakobsen, Mogens

    2005-02-01

    Samples of cocoa beans were taken on two separate occasions during heap and tray fermentations in Ghana, West Africa. In total 496 yeast isolates were identified by conventional microbiological analyses and by amplification of their ITS1-5.8S rDNA-ITS2 regions. For important species the identifications were confirmed by sequencing of the D1/D2 domain of the 5' end of the large subunit (26S) rDNA. Assimilations of organic acids and other carbon compounds were conducted. For dominant yeasts intraspecies variations were examined by determination of chromosome length polymorphism (CLP) using pulsed-field gel electrophoresis. For the heap fermentations maximum yeast cell counts of 9.1 x 10(7) were reached, whereas maximum yeast counts of 6.0 x 10(6) were reached for the tray fermentations. Candida krusei was found to be the dominant species during heap fermentation, followed by P. membranifaciens, P. kluyveri, Hanseniaspora guilliermondii and Trichosporon asahii, whereas Saccharomyces cerevisiae and P. membranifaciens were found to be the dominant species during tray fermentation followed by low numbers of C. krusei, P. kluyveri, H. guilliermondii and some yeast species of minor importance. For isolates within all dominant species CLP was evident, indicating that several different strains are involved in the fermentations. Isolates of C. krusei, P. membranifaciens, H. guilliermondii, T. asahii and Rhodotorula glutinis could be found on the surface of the cocoa pods and in some cases on the production equipment, whereas the origin of e.g. S. cerevisiae was not indicated by the results obtained. In conclusion, the results obtained show that fermentation of cocoa beans is a very inhomogeneous process with great variations in both yeast counts and species composition. The variations seem to depend especially on the processing procedure, but also the season and the post-harvest storage are likely to influence the yeast counts and the species composition. PMID:15691749

  3. Nanoliposomal Dry Powder Formulations

    PubMed Central

    Patel, Gaurang; Chougule, Mahavir; Singh, Mandip; Misra, Ambikanandan

    2013-01-01

    Liposomal dry powder formulations (DPFs) have proven their superiority over conventional DPFs due to favorably improved pharmacokinetics and pharmacodynamics of entrapped drugs, and thus, reduced local and systemic toxicities. Nanoliposomal DPFs (NLDPFs) provide stable, high aerosolization efficiency to deep lung, prolonged drug release, slow systemic dilution, and avoid macrophage uptake of encapsulated drug by carrier-based delivery of nano-range liposomes. This chapter describes methods of preparation of nanoliposomes (NLs) and NLDPFs, using various techniques, and their characterization with respect to size distribution, flow behavior, in vitro drug release profile, lung deposition, cellular uptake and cytotoxicity, and in vivo pharmacokinetics and pharmacodynamics. Some examples have been detailed for better understanding of the methods of preparation and evaluation of NLDPFs by investigators. PMID:19903555

  4. Mound powder loader, Mod 1

    SciTech Connect

    Gress, A.V. Jr.

    1985-08-21

    At the investigation of Sandia Albuquerque, a semiautomatic powder loader was designed and fabricated for pyrotechnics devices. The basic functions of the system were to load a precise, measured amount of powder into a charge holder and to compact the mixture to a specified density. This report documents the history, rationale, design, and performance of the Mod 1 loader.

  5. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  6. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  7. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  8. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  9. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  10. Synthesis of boron nitride powders

    NASA Astrophysics Data System (ADS)

    Dreissig, Dirk Horst

    2002-09-01

    In the materials science community there is much interest in the development of new, efficient approaches for preparing ceramic powders having properties or performance characteristics not found with powders produced by traditional metallurgical synthesis methods. In this regard, aerosol-based syntheses are finding general acceptance for the preparation of non-metal and metal oxide powders. In contrast, much less effort has been given to aerosol-type syntheses for non-oxide powders despite potentially useful benefits. This dissertation describes the application of two chemical systems in aerosol assisted vapor phase synthesis (AAVS) for the preparation of spherical morphology boron oxynitride, BNxOy, powders that are subsequently converted to spherical morphology boron nitride in a second nitridation step. Chapter 1 describes the AAVS synthesis of BNxOy powders using a reaction of an aqueous boric acid containing aerosol with ammonia at 1000°C. The effect of reactor tube material, total gas flow rate, ammonia concentration, boric acid concentration, and urea addition to the boric acid aerosol on the percent oxygen composition is described. The resulting BNxOy powders contain significant amounts of oxygen that require replacement in a second stage nitridation reaction at elevated temperature under ammonia. The influences of the reaction temperature profile, crucible geometry and transformation additive on final oxygen composition and powder crystallinity are described. Chapter 2 outlines the formation of BNxOy powders from an AAVS reaction between the boron precursor (MeO)3B and ammonia. The formation of the powders is studied as a function of total gas flow rate and ammonia concentration. In all cases the resulting powders contain lower levels of oxygen compared to powders produced from aqueous boric acid aerosols. The conversion of the BNxOy powders in the second stage nitridation reaction with ammonia is examined as a function of crucible geometry, temperature profile and ammonia flow rate. In support of this process, the molecular reaction between (MeO)3B and NH3 was reexamined. The adduct, (MeO)3B·NH3, was isolated and its molecular structure determined by single crystal X-ray diffraction techniques. The results of these studies provide guidance for more detailed studies that should result in industrial scale synthesis of spherical morphology BN which currently is not formed by standard metallurgical syntheses. This new material has potential applications in several areas including the formation of BN loaded organic polymer composites.

  11. A Conceptual Model for Shear-Induced Phase Behavior in Crystallizing Cocoa Butter

    SciTech Connect

    Mazzanti,G.; Guthrie, S.; Marangoni, A.; Idziak, S.

    2007-01-01

    We propose a conceptual model to explain the quantitative data from synchrotron X-ray diffraction experiments on the shear-induced phase behavior of cocoa butter, the main structural component of chocolate. We captured two-dimensional diffraction patterns from cocoa butter at crystallization temperatures of 17.5, 20.0, and 22.5 {sup o}C under shear rates from 45 to 1440 s{sup -1} and under static conditions. From the simultaneous analysis of the integrated intensity, correlation length, lamellar thickness, and crystalline orientation, we postulate a conceptual model to provide an explanation for the distribution of phases II, IV, V, and X and the kinetics of the process. As previously proposed in the literature, we assume that the crystallites grow layer upon layer of slightly different composition. The shear rate and temperature applied define these compositions. Simultaneously, the shear and temperature define the crystalline interface area available for secondary nucleation by promoting segregation and affecting the size distribution of the crystallites. The combination of these factors (composition, area, and size distribution) favors dramatically the early onset of phase V under shear and determines the proportions of phases II, IV, V, and X after the transition. The experimental observations, the methodology used, and the proposed explanation are of fundamental and industrial interest, since the structural properties of crystalline networks are determined by their microstructure and polymorphic crystalline state. Different proportions of the phases will thus result in different characteristics of the final material.

  12. Determination of biogenic amine profiles in conventional and organic cocoa-based products.

    PubMed

    Restuccia, Donatella; Spizzirri, U Gianfranco; Puoci, Francesco; Picci, Nevio

    2015-07-01

    Cocoa contains many compounds such as biogenic amines (BAs), known to influence consumer health. Spermidine, spermidine, putrescine, histamine, tyramine, ?-phenylethylamine, cadaverine and serotonine have been found in several cocoa-based products using HPLC with UV detection after derivatisation with dansyl-chloride. Once optimised in terms of linearity, percentage recovery, LOD, LOQ and repeatability, this method was applied to real samples. Total concentrations of BAs ranged from 5.7 to 79.0 µg g(-)(1) with wide variations depending on the type of sample. BAs present in all samples were in decreasing order: histamine (1.9-38.1 µg g(-)(1)) and tyramine (1.7-31.7 µg g(-)(1)), while putrescine (0.9-32.7 µg g(-)(1)), spermidine (1.0-9.7 µg g(-)(1)) and spermidine (0.6-9.3 µg g(-)(1)) were present in most of the samples. Cadaverine, serotonine and ?-phenylethylamine were present in a few samples at much lower concentrations. Organic samples always contained much lower levels of BAs than their conventional counterparts and, generally speaking, the highest amounts of BAs were found in the most processed products. PMID:25833003

  13. Microencapsulation of Bifidobacterium animalis subsp. lactis and Lactobacillus acidophilus in cocoa butter using spray chilling technology

    PubMed Central

    Pedroso, D.L.; Dogenski, M.; Thomazini, M.; Heinemann, R.J.B.; Favaro-Trindade, C.S.

    2013-01-01

    In the present study, the cells of Bifidobacterium animalis subsp. lactis (BI-01) and Lactobacillus acidophilus (LAC-04) were encapsulated in cocoa butter using spray-chilling technology. Survival assays were conducted to evaluate the resistance of the probiotics to the spray-chilling process, their resistance to the simulated gastric and intestinal fluids (SGF and SIF), and their stability during 90 days of storage. The viability of the cells was not affected by microencapsulation. The free and encapsulated cells of B. animalis subsp. lactis were resistant to both SGF and SIF. The micro-encapsulated cells of L. acidophilus were more resistant to SGF and SIF than the free cells; the viability of the encapsulated cells was enhanced by 67%, while the free cells reached the detection limit of the method (103 CFU/g). The encapsulated probiotics were unstable when they were stored at 20 °C. The population of encapsulated L. acidophilus decreased drastically when they were stored at 7 °C; only 20% of cells were viable after 90 days of storage. The percentage of viable cells of the encapsulated B. animalis subsp.lactis, however, was 72% after the same period of storage. Promising results were obtained when the microparticles were stored at ?18 °C; the freeze granted 90 days of shelf life to the encapsulated cells. These results suggest that the spray-chilling process using cocoa butter as carrier protects L. acidophilus from gastrointestinal fluids. However, the viability of the cells during storage must be improved. PMID:24516445

  14. Removal of heavy metals from acid soil leachate using cocoa shells in a batch counter-current sorption process

    Microsoft Academic Search

    Nathalie Meunier; Jean-François Blais; Rajeshwar Dayal Tyagi

    2004-01-01

    Soil washing is a widely used approach for metal-polluted sites decontamination. Metals solubilized during soil washing have to be extracted from the resulting soil leachates. Cocoa shells (CS) have been identified as a very efficient natural sorbent to remove Pb and other metals from acid soil leachates (ASL). A counter-current sorption process (CCSP) has been defined to reduce the CS

  15. Silica powders for powder evacuated thermal insulating panel and method

    DOEpatents

    Harris, M.T.; Basaran, O.A.; Kollie, T.G.; Weaver, F.J.

    1996-01-02

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm{sup 3} and an external surface area in the range of about 90 to 600 m{sup 2}/g is described. The silica powders are prepared by reacting a tetraalkyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders. 2 figs.

  16. Method for molding ceramic powders

    DOEpatents

    Janney, M.A.

    1990-01-16

    A method for molding ceramic powders comprises forming a slurry mixture including ceramic powder, a dispersant for the metal-containing powder, and a monomer solution. The monomer solution includes at least one multifunctional monomer, a free-radical initiator, and an organic solvent. The slurry mixture is transferred to a mold, and the mold containing the slurry mixture is heated to polymerize and crosslink the monomer and form a firm polymer-solvent gel matrix. The solid product may be removed from the mold and heated to first remove the solvent and subsequently remove the polymer, where after the product may be sintered.

  17. Ceramic powder for sintering materials

    NASA Technical Reports Server (NTRS)

    Akiya, H.; Saito, A.

    1984-01-01

    Surface activity of ceramic powders such as MgO and Al2O3, for use in sintering with sp. emphasis on their particle size, shape, particle size distribution, packing, and coexisting additives and impurities are reviewed.

  18. Luminescence of powdered uranium glasses

    NASA Technical Reports Server (NTRS)

    Eubanks, A. G.; Mcgarrity, J. M.; Silverman, J.

    1974-01-01

    Measurement of cathodoluminescence and photoluminescence efficiencies in powdered borosilicate glasses having different particle size and different uranium content. Excitation with 100 to 350 keV electrons and with 253.7 nm light was found to produce identical absolute radiant exitance spectra in powdered samples. The most efficient glass was one containing 29.4 wt% B2O3, 58.8 wt% SiO2, 9.8 wt% Na2O and 2.0 wt% UO2.

  19. Powder collection apparatus/method

    DOEpatents

    Anderson, Iver E. (Ames, IA); Terpstra, Robert L. (Ames, IA); Moore, Jeffery A. (Ames, IA)

    1994-01-11

    Device for separating and collecting ultrafine atomized powder from the gas stream of a gas atomizing apparatus comprises a housing having an interior wall oriented at an angle relative to horizontal so as to form a downwardly converging, conical expansion chamber, an inlet conduit communicated to the expansion chamber proximate an upper region thereof for receiving the gas stream, and an outlet proximate a lower region of the expansion chamber. The inlet conduit is oriented at a compound inclined angle (with respect to horizontal) selected to promote separation and collection of powder from the gas stream in the expansion chamber. The compound angle comprises a first entrance angle that is greater than the angle of repose of the powder on the housing interior wall such that any powder accumulation in the inlet conduit tends to flow down the wall toward the outlet. The second angle is selected generally equal to the angle of the housing interior wall measured from the same horizontal plane so as to direct the gas stream into the expansion chamber generally tangent to the housing interior wall to establish a downward swirling gas stream flow in the expansion chamber. A powder collection container is communicated to the outlet of the expansion chamber to collect the powder for further processing.

  20. Powder collection apparatus/method

    DOEpatents

    Anderson, I.E.; Terpstra, R.L.; Moore, J.A.

    1994-01-11

    Device for separating and collecting ultrafine atomized powder from the gas stream of a gas atomizing apparatus comprises a housing having an interior wall oriented at an angle relative to horizontal so as to form a downwardly converging, conical expansion chamber, an inlet conduit communicated to the expansion chamber proximate an upper region thereof for receiving the gas stream, and an outlet proximate a lower region of the expansion chamber. The inlet conduit is oriented at a compound inclined angle (with respect to horizontal) selected to promote separation and collection of powder from the gas stream in the expansion chamber. The compound angle comprises a first entrance angle that is greater than the angle of repose of the powder on the housing interior wall such that any powder accumulation in the inlet conduit tends to flow down the wall toward the outlet. The second angle is selected generally equal to the angle of the housing interior wall measured from the same horizontal plane so as to direct the gas stream into the expansion chamber generally tangent to the housing interior wall to establish a downward swirling gas stream flow in the expansion chamber. A powder collection container is communicated to the outlet of the expansion chamber to collect the powder for further processing. 4 figures.

  1. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  2. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  3. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  4. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  5. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  6. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  7. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  8. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  9. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  10. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be— (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  11. Ceramic oxide powders and the formation thereof

    DOEpatents

    Katz, J.L.; Chenghung Hung.

    1993-12-07

    Ceramic oxide powders and a method for their preparation. Ceramic oxide powders are obtained using a flame process whereby two or more precursors of ceramic oxides are introduced into a counterflow diffusion flame burner wherein said precursors are converted into ceramic oxide powders. The morphology, particle size, and crystalline form of the ceramic oxide powders are determined by process conditions. 14 figures.

  12. Ceramic oxide powders and the formation thereof

    DOEpatents

    Katz, Joseph L. (Baltimore, MD); Hung, Cheng-Hung (Baltimore, MD)

    1993-01-01

    Ceramic oxide powders and a method for their preparation. Ceramic oxide powders are obtained using a flame process whereby two or more precursors of ceramic oxides are introduced into a counterflow diffusion flame burner wherein said precursors are converted into ceramic oxide powders. The morphology, particle size, and crystalline form of the ceramic oxide powders are determined by process conditions.

  13. Theobroma cacao L., "The food of the Gods": quality determinants of commercial cocoa beans, with particular reference to the impact of fermentation.

    PubMed

    Lima, Lídia J R; Almeida, M Helena; Nout, M J Rob; Zwietering, Marcel H

    2011-09-01

    The quality of commercial cocoa beans, the principal raw material for chocolate production, relies on the combination of factors that include the type of planting material, the agricultural practices, and the post-harvest processing. Among these, the fermentation of the cocoa beans is still the most relevant since it is the process whereby the precursors of the cocoa flavor arise. The formation of these precursors depends on the activity of different microbial groups on the beans pulp. A comparison of fermentations in different countries showed that a well-defined microbial succession does not always take place and that the role of Bacillus spp. in this process remains unclear. Considering the overriding importance of the fermentation to achieve high quality commercial cocoa beans, we discuss the need of addressing the impact of the farming system, the ripeness state of the pods, and the role of microbial interactions on the fermentation in future research. In addition, the problem of high acidification cocoa beans, aspects dealing with the volatile fraction of the flavor, and the cocoa butter properties, all were identified as critical aspects that need further investigation. The standardization of the microbiological methods and the application of metagenomic approaches would magnify the knowledge in this domain. PMID:21838556

  14. Adding value to cocoa (Theobroma cacao L.) germplasm information with domestication history and admixture mapping.

    PubMed

    Marcano, Maria; Pugh, Tatiana; Cros, Emile; Morales, Sonia; Portillo Páez, Elvis A; Courtois, Brigitte; Glaszmann, Jean Christophe; Engels, Jan M M; Phillips, Wilbert; Astorga, Carlos; Risterucci, Ange Marie; Fouet, Olivier; González, Ventura; Rosenberg, Kai; Vallat, Isabelle; Dagert, Manuel; Lanaud, Claire

    2007-03-01

    A sound understanding of crop history can provide the basis for deriving novel genetic information through admixture mapping. We confirmed this, by using characterization data from an international collection of cocoa, collected 25 years ago, and from a contemporary plantation. We focus on the trees derived from three centuries of admixture between Meso-American Criollo and South American Forastero genomes. In both cacao sets of individuals, linkage disequilibrium extended over long genetic distances along chromosome regions, as expected in populations derived from recent admixture. Based on loose genome scans, genomic regions involved in useful traits were identified. Fifteen genomic regions involved in seed and fruit weight variation were highlighted. They correspond to ten previously identified QTLs and five novel ones. Admixture mapping can help to add value to genetic resources and thus, help to encourage investment in their conservation. PMID:17252253

  15. Analysis of expressed sequence tags (ESTs) from cocoa (Theobroma cacao L) upon infection with Phytophthora megakarya

    PubMed Central

    Naganeeswaran, Sudalaimuthu Asari; Subbian, Elain Apshara; Ramaswamy, Manimekalai

    2012-01-01

    Phytophthora megakarya, the causative agent of cacao black pod disease in West African countries causes an extensive loss of yield. In this study we have analyzed 4 libraries of ESTs derived from Phytophthora megakarya infected cocoa leaf and pod tissues. Totally 6379 redundant sequences were retrieved from ESTtik database and EST processing was performed using seqclean tool. Clustering and assembling using CAP3 generated 3333 non-redundant (907 contigs and 2426 singletons) sequences. The primary sequence analysis of 3333 non-redundant sequences showed that the GC percentage was 42.7 and the sequence length ranged from 101 – 2576 nucleotides. Further, functional analysis (Blast, Interproscan, Gene ontology and KEGG search) were executed and 1230 orthologous genes were annotated. Totally 272 enzymes corresponding to 114 metabolic pathways were identified. Functional annotation revealed that most of the sequences are related to molecular function, stress response and biological processes. The annotated enzymes are aldehyde dehydrogenase (E.C: 1.2.1.3), catalase (E.C: 1.11.1.6), acetyl-CoA C-acetyltransferase (E.C: 2.3.1.9), threonine ammonia-lyase (E.C: 4.3.1.19), acetolactate synthase (E.C: 2.2.1.6), O-methyltransferase (E.C: 2.1.1.68) which play an important role in amino acid biosynthesis and phenyl propanoid biosynthesis. All this information was stored in MySQL database management system to be used in future for reconstruction of biotic stress response pathway in cocoa. PMID:22359437

  16. Identification of Procyanidins in Cocoa ( Theobroma cacao ) and Chocolate Using High-Performance Liquid Chromatography\\/Mass Spectrometry

    Microsoft Academic Search

    John F. Hammerstone; Sheryl A. Lazarus; Alyson E. Mitchell; Robert Rucker; Harold H. Schmitz

    1999-01-01

    Monomeric and oligomeric procyanidins present in cocoa and chocolate were separated and identified using a modified normal-phase high-performance liquid chromatography (HPLC) method coupled with on-line mass spectrometry (MS) analysis using an atmospheric pressure ionization electrospray chamber. The chromatographic separation was achieved using a silica stationary phase in combination with a gradient ascending in polarity. This qualitative report confirms the presence

  17. Apparent metabolisable energy and digestibility of shea (Vitellaria paradoxa) fat, cocoa (Theobroma cacao) fat and soybean oil in broiler chicks.

    PubMed

    Dei, H K; Rose, S P; Mackenzie, A M

    2006-10-01

    1. The objective of this experiment was to determine and compare the apparent lipid digestibility coefficient and apparent metabolisable energy (AME) value of shea nut (Vitellaria paradoxa, Gaertn.) fat in broiler chickens with that of soybean oil and cocoa fat. 2. One hundred and sixty 13-d-old male broiler chicks were used in a randomised complete block design. The fats were added at 30, 60 and 90 g/kg to a basal diet. A tenth dietary treatment was the basal feed with no added fats or oils. The birds were fed on the diets for 8 d and all droppings were collected for the final 4 d. 3. The mean coefficient of apparent lipid digestibility for shea fat (0.58) was similar to that of cocoa fat (0.54) but lower than that of soybean oil (0.95). There was evidence of a lipid x concentration interaction with the 90 g/kg shea fat diet having low lipid digestibility (0.43). 4. There was an interaction between the effects of dietary lipid concentration and test lipid on AME but, at dietary levels of 60 g/kg and below, the AME of shea fat (22.0 MJ/kg DM) and cocoa fat (26.4 MJ/kg DM) was significantly lower than that of soybean oil (39.8 MJ/kg DM). PMID:17050106

  18. Effect of Dietary Cocoa Tea (Camellia ptilophylla) Supplementation on High-Fat Diet-Induced Obesity, Hepatic Steatosis, and Hyperlipidemia in Mice.

    PubMed

    Yang, Xiao Rong; Wat, Elaine; Wang, Yan Ping; Ko, Chun Hay; Koon, Chi Man; Siu, Wing Sum; Gao, Si; Cheung, David Wing Shing; Lau, Clara Bik San; Ye, Chuang Xing; Leung, Ping Chung

    2013-01-01

    Recent studies suggested that green tea has the potential to protect against diet-induced obesity. The presence of caffeine within green tea has caused limitations. Cocoa tea (Camellia ptilophylla) is a naturally decaffeinated tea plant. To determine whether cocoa tea supplementation results in an improvement in high-fat diet-induced obesity, hyperlipidemia and hepatic steatosis, and whether such effects would be comparable to those of green tea extract, we studied six groups (n = 10) of C57BL/6 mice that were fed with (1) normal chow (N); (2) high-fat diet (21% butterfat + 0.15% cholesterol, wt/wt) (HF); (3) a high-fat diet supplemented with 2% green tea extract (HFLG); (4) a high-fat diet supplemented with 4% green tea extract (HFHG); (5) a high-fat diet supplemented with 2% cocoa tea extract (HFLC); and (6) a high-fat diet supplemented with 4% cocoa tea extract (HFHC). From the results, 2% and 4% dietary cocoa tea supplementation caused a dose-dependent decrease in (a) body weight, (b) fat pad mass, (c) liver weight, (d) total liver lipid, (e) liver triglyceride and cholesterol, and (f) plasma lipids (triglyceride and cholesterol). These data indicate that dietary cocoa tea, being naturally decaffeinated, has a beneficial effect on high-fat diet-induced obesity, hepatomegaly, hepatic steatosis, and elevated plasma lipid levels in mice, which are comparable to green tea. The present findings have provided the proof of concept that dietary cocoa tea might be of therapeutic value and could therefore provide a safer and cost effective option for patients with diet-induced metabolic syndrome. PMID:23935682

  19. Polymer quenched prealloyed metal powder

    DOEpatents

    Hajaligol, Mohammad R. (Midlothian, VA); Fleischhauer, Grier (Midlothian, VA); German, Randall M. (State College, PA)

    2001-01-01

    A powder metallurgical process of preparing a sheet from a powder having an intermetallic alloy composition such as an iron, nickel or titanium aluminide. The sheet can be manufactured into electrical resistance heating elements having improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The iron aluminide has an entirely ferritic microstructure which is free of austenite and can include, in weight %, 4 to 32% Al, and optional additions such as .ltoreq.1% Cr, .gtoreq.0.05% Zr .ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Ni, .ltoreq.0.75% C, .ltoreq.0.1% B, .ltoreq.1% submicron oxide particles and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1% rare earth metal, and/or .ltoreq.3 % Cu. The process includes forming a non-densified metal sheet by consolidating a powder having an intermetallic alloy composition such as by roll compaction, tape casting or plasma spraying, forming a cold rolled sheet by cold rolling the non-densified metal sheet so as to increase the density and reduce the thickness thereof and annealing the cold rolled sheet. The powder can be a water, polymer or gas atomized powder which is subjecting to sieving and/or blending with a binder prior to the consolidation step. After the consolidation step, the sheet can be partially sintered. The cold rolling and/or annealing steps can be repeated to achieve the desired sheet thickness and properties. The annealing can be carried out in a vacuum furnace with a vacuum or inert atmosphere. During final annealing, the cold rolled sheet recrystallizes to an average grain size of about 10 to 30 .mu.m. Final stress relief annealing can be carried out in the B2 phase temperature range.

  20. Intradermal needle-free powdered drug injection

    E-print Network

    Liu, John (John Hsiao-Yung)

    2012-01-01

    This thesis presents a new method for needle-free powdered drug injection. The design, construction, and testing of a bench-top helium-powered device capable of delivering powder to controllable depths within the dermis ...

  1. Review: aqueous tape casting of ceramic powders

    Microsoft Academic Search

    D. Hotza; P. Greil

    1995-01-01

    Slurry formulations and processing parameters of the water-based tape casting of ceramic powders are reviewed. Additives include binders, like cellulose ethers, vinyl or acrylic-type polymers; plasticizers, like glycols; and dispersants, like ammonium salts of poly(acrylic acids). Mostly alumina powders have been employed. Hydrophobing of ceramic powders permits the aqueous processing even of water-reactive powders, like aluminium nitride. Non-toxicity and non-inflammability

  2. CCAR1/CoCoA pair-mediated recruitment of the Mediator defines a novel pathway for GATA1 function

    PubMed Central

    Mizuta, Shumpei; Minami, Tomoya; Fujita, Haruka; Kaminaga, Chihiro; Matsui, Keiji; Ishino, Ruri; Fujita, Azusa; Oda, Kasumi; Kawai, Asami; Hasegawa, Natsumi; Urahama, Norinaga; Roeder, Robert G.; Ito, Mitsuhiro

    2015-01-01

    The MED1 subunit of the Mediator transcriptional coregulator complex coactivates GATA1 and induces erythropoiesis. Here, we show the dual mechanism of GATA1- and MED1-mediated transcription. MED1 expression levels in K562 erythroleukemia cells paralleled the levels of GATA1-targeted gene transcription and erythroid differentiation. An N-terminal fragment of MED1, MED1(1–602), which is incapable of interacting with GATA1, enhanced GATA1-targeted gene transcription and erythroid differentiation, and introduction of MED1(1–602) into Med1?/? mouse embryonic fibroblasts (MEFs) partially rescued GATA1-mediated transcription. The C-terminal zinc-finger domain of GATA1 interacts with the MED1(1–602)-interacting coactivator CCAR1, CoCoA, and MED1(681–715). CCAR1 and CoCoA synergistically enhanced GATA1-mediated transcription from the ?-globin promoter in MEFs. Recombinant GATA1, CCAR1, CoCoA, and MED1(1–602) formed a complex in vitro, and GATA1, CCAR1, CoCoA, and MED1 were recruited to the ?-globin promoter in K562 cells during erythroid differentiation. Therefore, in addition to the direct interaction between GATA1 and MED1, CoCoA and CCAR1 appear to relay the GATA1 signal to MED1, and multiple modes of the GATA1-MED1 axis may help to fine-tune GATA1 function during GATA1-mediated homeostasis events. PMID:24245781

  3. Spontaneous organic cocoa bean box fermentations in Brazil are characterized by a restricted species diversity of lactic acid bacteria and acetic acid bacteria.

    PubMed

    Papalexandratou, Zoi; Vrancken, Gino; De Bruyne, Katrien; Vandamme, Peter; De Vuyst, Luc

    2011-10-01

    Spontaneous organic cocoa bean box fermentations were carried out on two different farms in Brazil. Physical parameters, microbial growth, bacterial species diversity [mainly lactic acid bacteria (LAB) and acetic acid bacteria (AAB)], and metabolite kinetics were monitored, and chocolates were produced from the fermented dry cocoa beans. The main end-products of the catabolism of the pulp substrates (glucose, fructose, and citric acid) by yeasts, LAB, and AAB were ethanol, lactic acid, mannitol, and/or acetic acid. Lactobacillus fermentum and Acetobacter pasteurianus were the predominating bacterial species of the fermentations as revealed through (GTG)(5)-PCR fingerprinting of isolates and PCR-DGGE of 16S rRNA gene PCR amplicons of DNA directly extracted from fermentation samples. Fructobacillus pseudoficulneus, Lactobacillus plantarum, and Acetobacter senegalensis were among the prevailing species during the initial phase of the fermentations. Also, three novel LAB species were found. This study emphasized the possible participation of Enterobacteriaceae in the cocoa bean fermentation process. Tatumella ptyseos and Tatumella citrea were the prevailing enterobacterial species in the beginning of the fermentations as revealed by 16S rRNA gene-PCR-DGGE. Finally, it turned out that control over a restricted bacterial species diversity during fermentation through an ideal post-harvest handling of the cocoa beans will allow the production of high-quality cocoa and chocolates produced thereof, independent of the fermentation method or farm. PMID:21839382

  4. 21 CFR 524.1005 - Furazolidone powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Furazolidone powder. 524.1005 Section 524... § 524.1005 Furazolidone powder. (a) Specifications...affected area and apply only enough powder to impart a light yellow color...lacerations, and following firing (heat or electrocautery)....

  5. Agglomeration of Food Powder and Applications

    Microsoft Academic Search

    K. Dhanalakshmi; S. Ghosal; S. Bhattacharya

    2011-01-01

    Agglomeration has many applications in food processing and major applications include easy flow table salt, dispersible milk powder and soup mix, instant chocolate mix, beverage powder, compacted cubes for nutritional-intervention program, health bars using expanded\\/puffed cereals, etc. The main purpose of agglomeration is to improve certain physical properties of food powders such as bulk density, flowability, dispersability, and stability. Agglomerated

  6. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  7. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  8. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  9. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  10. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  11. Effect of Powder Polydispersity on Aerosol Generation

    Microsoft Academic Search

    Nora Y. K. Chew; Hak-Kim Chan

    Purpose. We investigated the effect of primary powder polydispersity on the generation of pharmaceutical powder aerosols, using mannitol and bovine serum albu- min (BSA) as the model compounds. Methods. Primary powders with different polydispersity but comparable physical and mass median aerodynamic diameter (MMAD) were obtained from spray drying. The polydispersity, i.e. the width of the particle size distribution, of the

  12. MESOSCALE SIMULATIONS OF POWDER COMPACTION

    SciTech Connect

    Lomov, Ilya; Fujino, Don; Antoun, Tarabay; Liu, Benjamin [Lawrence Livermore National Laboratory, P. O. Box 808, Livermore CA 94551 (United States)

    2009-12-28

    Mesoscale 3D simulations of shock compaction of metal and ceramic powders have been performed with an Eulerian hydrocode GEODYN. The approach was validated by simulating a well-characterized shock compaction experiment of a porous ductile metal. Simulation results using the Steinberg material model and handbook values for solid 2024 aluminum showed good agreement with experimental compaction curves and wave profiles. Brittle ceramic materials are not as well studied as metals, so a simple material model for solid ceramic (tungsten carbide) has been calibrated to match experimental compaction curves. Direct simulations of gas gun experiments with ceramic powders have been performed and showed good agreement with experimental data. The numerical shock wave profile has same character and thickness as that measured experimentally using VISAR. The numerical results show reshock states above the single-shock Hugoniot line as observed in experiments. We found that for good quantitative agreement with experiments 3D simulations are essential.

  13. Particle adhesion in powder coating

    SciTech Connect

    Mazumder, M.K.; Wankum, D.L.; Knutson, M.; Williams, S. [Univ. of Arkansas, Little Rock, AR (United States); Banerjee, S. [Univ. of Georgia, Athens, GA (United States)

    1996-12-31

    Electrostatic powder coating is a widely used industrial painting process. It has three major advantages: (1) it provides high quality durable finish, (2) the process is environmentally friendly and does not require the use of organic solvents, and (3) it is economically competitive. The adhesion of electrostatically deposited polymer paint particles on the grounded conducting substrate depends upon many parameters: (a) particle size and shape distributions, (b) electrostatic charge distributions, (c) electrical resistivity, (d) dielectric strength of the particles, (e) thickness of the powder film, (f) presence and severity of the back corona, and (g) the conductivity and surface properties of the substrate. The authors present a model on the forces of deposition and adhesion of corona charged particles on conducting substrates.

  14. Analysis of powder diffraction data

    Microsoft Academic Search

    M. J. Cooper

    1982-01-01

    A comparison has been carried out between the results of analyses of several sets of neutron powder diffraction data using three different methods: the Rietveld method (H.M. Rietveld, Acta. Cryst. 2, 151-152 (1967): J. Appl. Cryst. 2, 65-71 (1969), a modification of the Rietveld method to include off-diagonal terms in the weight matrix (C.P. Clarke and J.S. Rollett, Acta. Cryst.

  15. Operationally realistic validation for prediction of cocoa sensory qualities by high-throughput mass spectrometry.

    PubMed

    Wood, Jacqueline E; Allaway, David; Boult, Emma; Scott, Ian M

    2010-07-15

    The potential of analytical chemistry to predict sensory qualities of food materials is a major current theme. Standard practice is cross-validation (CV), where a set of chemical and associated sensory data is partitioned so chemometric models can be developed on training subsets, and validated on held-out subsets. CV demonstrates prediction, but is an unlikely scenario for industrial operations, where concomitant data acquisition for model development and test materials would be unwieldy. We evaluated cocoa materials of diverse provenance, and analyzed on different dates to those used in model development. Liquor extracts were analyzed by flow-injection electrospray-mass spectrometry (FIE-MS), a novel method for sensory quality prediction. FIE-MS enabled prediction of sensory qualities described by trained human panelists. Optimal models came from the Weka data-mining algorithm SimpleLinearRegression, which learns a model for the attribute giving minimal training error, which was (-)-epicatechin. This flavonoid likewise dominated partial least-squares (PLS)-regression models. Refinements of PLS (orthogonal-PLS or orthogonal signal correction) gave poorer generalization to different test sets, as did support vector machines, whose hyperparameters could not be optimized in training to avoid overfitting. In conclusion, if chemometric overfitting is avoided, chemical analysis can predict sensory qualities of food materials under operationally realistic conditions. PMID:20557115

  16. Hard cocoa butter replacers from mango seed fat and palm stearin.

    PubMed

    Jahurul, M H A; Zaidul, I S M; Nik Norulaini, N A; Sahena, F; Abedin, M Z; Mohamed, A; Mohd Omar, A K

    2014-07-01

    The blending effects of mango seed fat (MSF), extracted using supercritical fluid, and palm stearin (PS) to formulate hard cocoa butter replacers (CBRs), were investigated. The triglycerides (TG), thermal properties and solid fat content (SFC) of the formulated blends were determined using different chromatographic and thermal techniques. All the blends had three main TGs; namely, 1,3-dipalmitoyl-2-oleoylglycerol (POP) (8.6-17.7%), 1-palmitoyl-2-oleoyl-3-stearoyl-glycerol (POS) (12.6-19.6%), and 1,3-distearoyl-2-oleoyl-glycerol (SOS) (37.2-31.4%), with SOS being the major component. The melting peak temperatures gradually increased and shifted towards higher temperatures with PS. The crystallization onset temperatures increased, while the offset decreased with PS. The SFC did not drop to 0% at 37.5°C, which was shifted to 0% at and above 40°C for some blends. The studies revealed that CBRs could be prepared by blending MSF and PS, and they could be utilised by chocolate manufacturers in tropical countries. PMID:24518349

  17. Anti-Corrosive Powder Particles

    NASA Technical Reports Server (NTRS)

    Parker, Donald; MacDowell, Louis, III

    2005-01-01

    The National Aeronautics and Space Administration (NASA) seeks partners for a new approach in protecting embedded steel surfaces from corrosion. Corrosion of reinforced steel in concrete structures is a significant problem for NASA structures at Kennedy Space Center (KSC) because of the close proximity of the structures to salt spray from the nearby Atlantic Ocean. In an effort to minimize the damage to such structures, coatings were developed that could be applied as liquids to the external surfaces of a substrate in which the metal structures were embedded. The Metallic Pigment Powder Particle technology was developed by NASA at KSC. This technology combines the metallic materials into a uniform particle. The resultant powder can be sprayed simultaneously with a liquid binder onto the surface of concrete structures with a uniform distribution of the metallic pigment for optimum cathodic protection of the underlying steel in the concrete. Metallic Pigment Powder Particle technology improves upon the performance of an earlier NASA technology Liquid Galvanic Coating (U.S. Patent No. 6,627,065).

  18. Realistic intake of a flavanol-rich soluble cocoa product increases HDL-cholesterol without inducing anthropometric changes in healthy and moderately hypercholesterolemic subjects.

    PubMed

    Martínez-López, Sara; Sarriá, Beatriz; Sierra-Cinos, José Luis; Goya, Luis; Mateos, Raquel; Bravo, Laura

    2014-02-01

    To assess whether antioxidant, anti-inflammatory and other cardio-protective effects attributed to cocoa are achieved when regularly consuming moderate amounts of a flavanol-rich soluble cocoa product, a non-randomized, controlled, crossover, free-living study was carried out in healthy (n = 24; 25.9 ± 5.6 years) and moderately hypercholesterolemic (200-240 mg dL(-1); n = 20; 30.0 ± 10.3 years) volunteers. Participants consumed two servings per day (7.5 g per serving) of a soluble cocoa product (providing 45.3 mg flavanols per day) in milk, which was compared with consuming only milk during a 4 week period. The effects on systolic and diastolic blood pressure and heart rate were determined, as well as on serum lipid and lipoprotein profiles, interleukins (IL)-1?, IL-6, IL-8, IL-10, tumor necrosis factor-? (TNF-?), monocyte chemoattractant protein-1 (MCP-1), vascular (VCAM-1) and intercellular cell adhesion molecules (ICAM-1), serum malondialdehyde (MDA), carbonyl groups (CG), ferric reducing/antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and free radical scavenging capacity (ABTS). During the study, the volunteers' diets and physical activity were also evaluated, as well as any changes in weight, skin folds, circumferences and related anthropometric parameters. Cocoa and certain polyphenol-rich fruits and vegetables and their derivatives were restricted. After consuming the cocoa product positive effects were observed such as an increase in serum HDL-C (p < 0.001) and dietary fiber intake (p = 0.050), whereas IL-10 decreased (p = 0.022). Other cardiovascular-related biomarkers and anthropometric parameters were unaffected. We have therefore concluded that regular consumption of this cocoa product in a Spanish-Mediterranean diet may protect against cardiovascular disease in healthy and hypercholesterolemic subjects without producing any weight gain or other anthropometric changes. PMID:24394704

  19. Phylogenetic Analysis of a Spontaneous Cocoa Bean Fermentation Metagenome Reveals New Insights into Its Bacterial and Fungal Community Diversity

    PubMed Central

    Illeghems, Koen; De Vuyst, Luc; Papalexandratou, Zoi; Weckx, Stefan

    2012-01-01

    This is the first report on the phylogenetic analysis of the community diversity of a single spontaneous cocoa bean box fermentation sample through a metagenomic approach involving 454 pyrosequencing. Several sequence-based and composition-based taxonomic profiling tools were used and evaluated to avoid software-dependent results and their outcome was validated by comparison with previously obtained culture-dependent and culture-independent data. Overall, this approach revealed a wider bacterial (mainly ?-Proteobacteria) and fungal diversity than previously found. Further, the use of a combination of different classification methods, in a software-independent way, helped to understand the actual composition of the microbial ecosystem under study. In addition, bacteriophage-related sequences were found. The bacterial diversity depended partially on the methods used, as composition-based methods predicted a wider diversity than sequence-based methods, and as classification methods based solely on phylogenetic marker genes predicted a more restricted diversity compared with methods that took all reads into account. The metagenomic sequencing analysis identified Hanseniaspora uvarum, Hanseniaspora opuntiae, Saccharomyces cerevisiae, Lactobacillus fermentum, and Acetobacter pasteurianus as the prevailing species. Also, the presence of occasional members of the cocoa bean fermentation process was revealed (such as Erwinia tasmaniensis, Lactobacillus brevis, Lactobacillus casei, Lactobacillus rhamnosus, Lactococcus lactis, Leuconostoc mesenteroides, and Oenococcus oeni). Furthermore, the sequence reads associated with viral communities were of a restricted diversity, dominated by Myoviridae and Siphoviridae, and reflecting Lactobacillus as the dominant host. To conclude, an accurate overview of all members of a cocoa bean fermentation process sample was revealed, indicating the superiority of metagenomic sequencing over previously used techniques. PMID:22666442

  20. Isolation, structure determination, synthesis, and sensory activity of N-phenylpropenoyl-L-amino acids from cocoa (Theobroma cacao).

    PubMed

    Stark, Timo; Hofmann, Thomas

    2005-06-29

    Application of chromatographic separation and taste dilution analyses recently revealed besides procyanidins a series of N-phenylpropenoyl amino acids as the key contributors to the astringent taste of nonfermented cocoa beans as well as roasted cocoa nibs. Because these amides have as yet not been reported as key taste compounds, this paper presents the isolation, structure determination, and sensory activity of these amino acid amides. Besides the previously reported (-)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-3-hydroxy-L-tyrosine (clovamide), (-)-N-[4'-hydroxy-(E)-cinnamoyl]-L-tyrosine (deoxyclovamide), and (-)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-tyrosine, seven additional amides, namely, (+)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-aspartic acid, (+)-N-[4'-hydroxy-(E)-cinnamoyl]-L-aspartic acid, (-)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-glutamic acid, (-)-N-[4'-hydroxy-(E)-cinnamoyl]-L-glutamic acid, (-)-N-[4'-hydroxy-(E)-cinnamoyl]-3-hydroxy-L-tyrosine, (+)-N-[4'-hydroxy-3'-methoxy-(E)-cinnamoyl]-L-aspartic acid, and (+)-N-[(E)-cinnamoyl]-L-aspartic acid, were identified for the first time in cocoa products by means of LC-MS/MS, 1D/2D-NMR, UV-vis, CD spectroscopy, and polarimetry, as well as independent enantiopure synthesis. Using the recently developed half-tongue test, human recognition thresholds for the astringent and mouth-drying oral sensation were determined to be between 26 and 220 micromol/L (water) depending on the amino acid moiety. In addition, exposure to light rapidly converted these [E]-configured N-phenylpropenoyl amino acids into the corresponding [Z]-isomers, thus indicating that analysis of these compounds in food and plant materials needs to be performed very carefully in the absence of light to prevent artifact formation. PMID:15969528

  1. Structures, sensory activity, and dose/response functions of 2,5-diketopiperazines in roasted cocoa nibs (Theobroma cacao).

    PubMed

    Stark, Timo; Hofmann, Thomas

    2005-09-01

    The taste compounds inducing the blood-like, metallic bitter taste sensation reported recently for a dichloromethane extract prepared from roasted cocoa nibs were identified as a series of 25 diketopiperazines by means of HPLC degustation, LC-MS/MS, and independent synthesis. Among these 25 compounds, 13 cis-configured diketopiperazines, namely, cyclo(L-IIe-L-Phe), cyclo(L-Val-L-Leu), cyclo(L-Pro-L-Pro), cyclo(L-IIe-L-Pro), cyclo(L-Val-L-Tyr), cyclo(L-Ala-L-Tyr), cyclo(L-Phe-L-Ser), cyclo(L-Ala-L-IIe), cyclo(L-Leu-L-Phe), cyclo(L-Pro-L-Val), cyclo(L-Pro-L-Thr), cyclo(L-Pro-L-Tyr), and cyclo(L-Val-L-Val) were identified for the first time in cocoa. In addition, the taste recognition thresholds for the metallic as well as the bitter taste of the diketopiperazines were determined, and after quantitative analysis by using two diastereomeric diketopiperazines as the internal standards, the sensory impact of the diketopiperazines was evaluated on the basis of their dose-over-threshold (DoT) factors calculated as the ratio of the concentration and the threshold concentration of a compound. These data revealed DoT factors above 1.0 exclusively for cis-cyclo(L-Pro-L-Val), cis-cyclo(L-Val-L-Leu), cis-cyclo(L-Ala-L-Ile), cis-cyclo(L-Ala-L-Leu), and cis-cyclo(L-Ile-L-Pro), whereas all of the other diketopiperazines were present below their individual bitter taste threshold concentrations and should therefore not contribute to the cocoa taste. Because the DoT factors do not consider the nonlinear relationship between the concentration and gustatory response of an individual compound, we, for the first time, report on the recording of dose/response functions describing the human bitter taste perception of diketopiperazines more precisely. PMID:16131134

  2. Sensory-guided decomposition of roasted cocoa nibs (Theobroma cacao) and structure determination of taste-active polyphenols.

    PubMed

    Stark, Timo; Bareuther, Sabine; Hofmann, Thomas

    2005-06-29

    Sequential application of solvent extraction, gel permeation chromatography, and RP-HPLC in combination with taste dilution analyses, followed by LC-MS and 1D/2D-NMR experiments and thiolytic degradation, revealed that, besides theobromine and caffeine, the flavan-3-ols epicatechin, catechin, procyanidin B-2, procyanidin B-5, procyanidin C-1, [epicatechin-(4beta-->8)](3)-epicatechin, and [epicatechin-(4beta-->8)](4)-epicatechin were among the key compounds contributing to the bitter taste as well as the astringent mouthfeel imparted upon consumption of roasted cocoa. In addition, a series of quercetin, naringenin, luteolin, and apigenin glycopyranosides as well as a family of not previously identified amino acid amides, namely, (+)-N-[4'-hydroxy-(E)-cinnamoyl]-L-aspartic acid, (+)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-aspartic acid, (-)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-glutamic acid, (-)-N-[4'-hydroxy-(E)-cinnamoyl]-L-glutamic acid, (-)-N-[4'-hydroxy-(E)-cinnamoyl]-3-hydroxy-L-tyrosine, (+)-N-[4'-hydroxy-3'-methoxy-(E)-cinnamoyl]-L-aspartic acid, and (+)-N-(E)-cinnamoyl-L-aspartic acid, have been identified as key astringent compounds of roasted cocoa. Furthermore, (-)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-3-hydroxy-l-tyrosine (clovamide), (-)-N-[4'-hydroxy-(E)-cinnamoyl]-L-tyrosine (deoxyclovamide), and (-)-N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-tyrosine, reported previously as antioxidants, have been found as contributors of cocoa's astringent taste. By means of the half-tongue test, the taste thresholds of flavan-3-ols and glycosides have been determined. PMID:15969527

  3. Consumption of cocoa flavanols results in an acute improvement in visual and cognitive functions.

    PubMed

    Field, David T; Williams, Claire M; Butler, Laurie T

    2011-06-01

    Cocoa flavanols (CF) influence physiological processes in ways that suggest their consumption may improve aspects of neural function, and previous studies have found positive influences of CF on cognitive performance. In this preliminary study we investigated whether visual, as well as cognitive, function is influenced by an acute dose of CF in young adults. We employed a randomized, single-blinded, order counterbalanced, crossover design in which 30 healthy adults consumed both dark chocolate containing 720mg CF and a matched quantity of white chocolate, with a one week interval between testing sessions. Visual contrast sensitivity was assessed by reading numbers that became progressively more similar in luminance to their background. Motion sensitivity was assessed firstly by measuring the threshold proportion of coherently moving signal dots that could be detected against a background of random motion, and secondly by determining the minimum time required to detect motion direction in a display containing a high proportion of coherent motion. Cognitive performance was assessed using a visual spatial working memory for location task and a choice reaction time task designed to engage processes of sustained attention and inhibition. Relative to the control condition, CF improved visual contrast sensitivity and reduced the time required to detect motion direction, but had no statistically reliable effect on the minimum proportion of coherent motion that could be detected. In terms of cognitive performance, CF improved spatial memory and performance on some aspects of the choice reaction time task. As well as extending the range of cognitive tasks that are known to be influenced by CF consumption, this is the first report of acute effects of CF on the efficiency of visual function. These acute effects can be explained by increased cerebral blood flow caused by CF, although in the case of contrast sensitivity there may be an additional contribution from CF induced retinal blood flow changes. PMID:21324330

  4. High-cocoa polyphenol-rich chocolate improves blood pressure in patients with diabetes and hypertension

    PubMed Central

    Rostami, Ali; Khalili, Mohammad; Haghighat, Neda; Eghtesadi, Shahryar; Shidfar, Farzad; Heidari, Iraj; Ebrahimpour-Koujan, Soraiya; Eghtesadi, Maryam

    2015-01-01

    BACKGROUND The aim was to examine the effects of high-cocoa polyphenol-rich chocolate on lipid profiles, weight, blood pressure, glycemic control, and inflammation in individuals with Type 2 diabetes and hypertension. METHODS Sixty individuals [32 in dark chocolate group (DCG) and 28 in white chocolate group (WCG)] with Type 2 diabetes on stable medication were enrolled in a randomized, placebo-controlled double-blind study. Subjects were randomized to consume 25 g DCG or WCG for 8 weeks. Changes in weight, blood pressure, glycemic control, lipid profile, and high sensitive C-reactive protein (hsCRP) were measured at the beginning and end of the intervention. This clinical trial was registered at the Iranian registry of clinical trials. RESULTS In DCC group, compared with baseline, serum levels of Apo A-1 (P = 0.045) was increased and fasting blood sugar (FBS) (P = 0.027), hemoglobin A1c (HbA1c) (P = 0.025), Apo B (P = 0.012) and Log of hsCRP (P = 0.043) levels were decreased at the end of study. No changes were seen within the WCG in studied parameters. High polyphenol chocolate consumption compared to white chocolate resulted in significant decrease in of systolic (?5.93 ± 6.25 vs. ?1.07 ± 7.97 mmHg, P = 0.004) and diastolic blood pressure (?6.4 ± 6.25 vs. 0.17 ± 7.9 mmHg, P = 0.002), FBS (?7.84 ± 19.15 vs. 4.00 ± 20.58 mg/dl, P = 0.019) over the course of 8 weeks of daily chocolate consumption neither weight nor body mass index and TG levels altered from baseline. CONCLUSION High polyphenol chocolate is effective in improving TG levels in hypertensive patients with diabetes and decreasing blood pressure and FBS without affecting weight, inflammatory markers, insulin resistance or glycemic control.

  5. Process for the synthesis of iron powder

    DOEpatents

    Welbon, W.W.

    1983-11-08

    A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder. 2 figs.

  6. Process for the synthesis of iron powder

    DOEpatents

    Not Available

    1982-03-06

    A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder.

  7. Powder handling for automated fuel processing

    SciTech Connect

    Frederickson, J.R.; Eschenbaum, R.C.; Goldmann, L.H.

    1989-04-09

    Installation of the Secure Automated Fabrication (SAF) line has been completed. It is located in the Fuel Cycle Plant (FCP) at the Department of Energy's (DOE) Hanford site near Richland, Washington. The SAF line was designed to fabricate advanced reactor fuel pellets and assemble fuel pins by automated, remote operation. This paper describes powder handling equipment and techniques utilized for automated powder processing and powder conditioning systems in this line. 9 figs.

  8. Thixoforming of Stellite Powder Compacts

    NASA Astrophysics Data System (ADS)

    Hogg, S. C.; Atkinson, H. V.; Kapranos, P.

    2007-04-01

    Thixoforming involves processing metallic alloys in the semi-solid state. The process requires the microstructure to be spheroidal when part-solid and part-liquid i.e. to consist of solid spheroids surrounded by liquid. The aim of this work was to investigate whether powder compacts can be used as feedstock for thixoforming and whether the consolidating pressure in the thixoformer can be used to remove porosity from the compact. The powder compacts were made from stellite 6 and stellite 21 alloys, cobalt-based alloys widely used for e.g. manufacturing prostheses. Isothermal heat treatments of small samples in the consolidated state showed the optimum thixoforming temperature to be in the range 1340°C-1350°C for both materials. The alloys were thixoformed into graphite dies and flowed easily to fill the die. Porosity in the thixoformed components was lower than in the starting material. Hardness values at various positions along the radius of the thixoformed demonstrator component were above the specification for both alloys.

  9. Synthesis of mullite powders by acrylamide polymerization.

    SciTech Connect

    Sin, A.; Picciolo, J. J.; Lee, R. H.; Gutierrez-Mora, F.; Goretta, K. C.; Energy Technology; INPG-CNRS

    2001-09-01

    Mullite (3Al{sub 2}O{sub 3} {center_dot} 2SiO{sub 2}) ceramics and composites are widely used. Synthesis of mullite powders, especially those that can be readily sintered, remains a focus of much current research. In support of recent efforts to fabricate mullite fibrous monoliths and to use superplastic flow to join ceramics, we have looked to synthesize reactive mullite powders. Recent advances in application of acrylamide polymers to ceramic synthesis offer promise of obtaining large quantities of high-quality powder at relatively low cost. We report here on synthesis from acrylamide monomers of mullite powders of two interesting particle sizes.

  10. Dendritic microstructure in argon atomized superalloy powders

    NASA Technical Reports Server (NTRS)

    Tewari, S. N.; Kumar, Mahundra

    1986-01-01

    The dendritic microstructure of atomized nickel base superalloy powders (Ni-20 pct Cr, NIMONIC-80A, ASTROALOY, and ZHS6-K) was studied. Prealloyed vacuum induction melted ingots were argon-atomized, the powders were cooled to room temperature, and various powder-size fractions were examined by optical metallography. Linear correlations were obtained for the powder size dependence of the secondary dendrite arm spacing, following the expected d-alpha (R) to the m power dependence on the particle size for all four superalloy compositions. However, the Ni-20 pct Cr alloy, which had much coarser arm spacing as compared to the other three alloys, had a much larger value of m.

  11. Accumulation of a cocoa-butter-like lipid by Yarrowia lipolytica cultivated on agro-industrial residues.

    PubMed

    Papanikolaou, Seraphim; Muniglia, Lionel; Chevalot, Isabelle; Aggelis, George; Marc, Ivan

    2003-02-01

    Yarrowia lipolytica was cultivated on mixtures of saturated free fatty acids (an industrial derivative of animal fat called stearin), technical glycerol (the main by-product of bio-diesel production facilities), and glucose. The utilization of technical glycerol and stearin as co-substrates resulted in higher lipid synthesis and increased citric acid production than the combination of glucose and stearin. The lipids produced contained significant amounts of stearic acid (50-70%, wt/wt) and lower ones of palmitic (15-20%, wt/wt), oleic (7-20%, wt/wt), and linoleic (2-7%, wt/wt) acid. Single-cell oil having a composition similar to cocoa-butter up to 3.4 g/L was produced, whereas in some cases relatively increased citric acid quantities (up to 14 g/L) were excreted into the growth medium. The microorganism presented a high specificity for lauric, myristic, and palmitic acid, while a discrimination for the stearic acid was observed. As a conclusion, microbial metabolism could be directed by using mixtures of inexpensive saturated fats, glycerol, and glucose as co-substrates, in order to accumulate lipids with predetermined composition, e.g., cocoa-butter equivalents. PMID:12520368

  12. The relic Criollo cacao in Belize- genetic diversity and relationship with Trinitario and other cacao clones held in the International Cocoa Genebank, Trinidad

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cacao (Theobroma cacao L.) is native to the South American rainforest but it was domesticated in Mesoamerica. The relic Criollo cocoa in Belize has been well known in the premium chocolate market for its high-quality. Knowledge of genetic diversity in this variety is essential for efficient conserva...

  13. Effect of cocoa and green tea on biomarkers of glucose regulation, oxidative stress, inflammation and hemostasis in obese adults at risk for insulin resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavanols may provide protection against insulin resistance, but little is known about the amounts and types of flavanols that may be efficacious. This study was designed to determine whether cocoa flavanols, over a range of intakes, improve biomarkers of glucose regulation, inflammation and hemost...

  14. Towards the understanding of the cocoa transcriptome: Production and analysis of an exhaustive dataset of ESTs of Theobroma cacao L. generated from various tissues and under various conditions

    Microsoft Academic Search

    Xavier Argout; Olivier Fouet; Patrick Wincker; Karina Gramacho; Thierry Legavre; Xavier Sabau; Ange Marie Risterucci; Corinne Da Silva; Julio Cascardo; Mathilde Allegre; David Kuhn; Joseph Verica; Brigitte Courtois; Gaston Loor; Regis Babin; Olivier Sounigo; Michel Ducamp; Mark J Guiltinan; Manuel Ruiz; Laurence Alemanno; Regina Machado; Wilberth Phillips; Ray Schnell; Martin Gilmour; Eric Rosenquist; David Butler; Siela Maximova; Claire Lanaud

    2008-01-01

    BACKGROUND: Theobroma cacao L., is a tree originated from the tropical rainforest of South America. It is one of the major cash crops for many tropical countries. T. cacao is mainly produced on smallholdings, providing resources for 14 million farmers. Disease resistance and T. cacao quality improvement are two important challenges for all actors of cocoa and chocolate production. T.

  15. The acute and sub-chronic effects of cocoa flavanols on mood, cognitive and cardiovascular health in young healthy adults: a randomized, controlled trial

    PubMed Central

    Massee, Laura A.; Ried, Karin; Pase, Matthew; Travica, Nikolaj; Yoganathan, Jaesshanth; Scholey, Andrew; Macpherson, Helen; Kennedy, Greg; Sali, Avni; Pipingas, Andrew

    2015-01-01

    Cocoa supplementation has been associated with benefits to cardiovascular health. However, cocoa's effects on cognition are less clear. A randomized, placebo-controlled, double-blind clinical trial (n = 40, age M = 24.13 years, SD = 4.47 years) was conducted to investigate the effects of both acute (same-day) and sub-chronic (daily for four-weeks) 250 mg cocoa supplementation on mood and mental fatigue, cognitive performance and cardiovascular functioning in young, healthy adults. Assessment involved repeated 10-min cycles of the Cognitive Demand Battery (CDB) encompassing two serial subtraction tasks (Serial Threes and Sevens), a Rapid Visual Information Processing task, and a mental fatigue scale over the course of half an hour. The Swinburne University Computerized Cognitive Assessment Battery (SUCCAB) was also completed to evaluate cognition. Cardiovascular function included measuring both peripheral and central blood pressure and cerebral blood flow. At the acute time point, consumption of cocoa significantly improved self-reported mental fatigue and performance on the Serial Sevens task in cycle one of the CDB. No other significant effects were found. This trial was registered with the Australian and New Zealand Clinical Trial Registry (Trial ID: ACTRN12613000626763). Accessible via http://www.anzctr.org.au/TrialSearch.aspx?searchTxt=ACTRN12613000626763&ddlSearch=Registered.

  16. Induction and accumulation of caffeine in young, actively growing leaves of cocoa ( Theobroma cacao L.) by wounding or infection with Crinipellis perniciosa

    Microsoft Academic Search

    Madhu Aneja; Thomas Gianfagna

    2001-01-01

    Crinipellis perniciosa, the causal agent of witches' broom disease, attacks young actively growing shoots, flowers and developing fruits of cocoa (Theobroma cacao L.). Infected shoots become fasciated and a profusion of hypertrophic shoots with small leaves develop from the lateral buds. This is followed by desiccation and death of the infected stem and leaves. Infected stem tissue contains significant amounts

  17. Applying meta-pathway analyses through metagenomics to identify the functional properties of the major bacterial communities of a single spontaneous cocoa bean fermentation process sample.

    PubMed

    Illeghems, Koen; Weckx, Stefan; De Vuyst, Luc

    2015-09-01

    A high-resolution functional metagenomic analysis of a representative single sample of a Brazilian spontaneous cocoa bean fermentation process was carried out to gain insight into its bacterial community functioning. By reconstruction of microbial meta-pathways based on metagenomic data, the current knowledge about the metabolic capabilities of bacterial members involved in the cocoa bean fermentation ecosystem was extended. Functional meta-pathway analysis revealed the distribution of the metabolic pathways between the bacterial members involved. The metabolic capabilities of the lactic acid bacteria present were most associated with the heterolactic fermentation and citrate assimilation pathways. The role of Enterobacteriaceae in the conversion of substrates was shown through the use of the mixed-acid fermentation and methylglyoxal detoxification pathways. Furthermore, several other potential functional roles for Enterobacteriaceae were indicated, such as pectinolysis and citrate assimilation. Concerning acetic acid bacteria, metabolic pathways were partially reconstructed, in particular those related to responses toward stress, explaining their metabolic activities during cocoa bean fermentation processes. Further, the in-depth metagenomic analysis unveiled functionalities involved in bacterial competitiveness, such as the occurrence of CRISPRs and potential bacteriocin production. Finally, comparative analysis of the metagenomic data with bacterial genomes of cocoa bean fermentation isolates revealed the applicability of the selected strains as functional starter cultures. PMID:25998815

  18. The Effect of Powder Recycling in Direct Metal Laser Deposition on Powder and Manufactured Part Characteristics

    Microsoft Academic Search

    P. A. Carroll; A. J. Pinkerton; J. Allen; W Syed; H Sezer; P. Brown; G. Ng; L. Li

    A potential way of improving the material efficiency and cost effectiveness of the Direct Metal Laser Deposition (DMLD) process is to take powder that is not utilised in each deposition attempt and re-use it in subsequent attempts (powder recycling). Currently, this is not widely implemented for fear of a detrimental effect on part quality. This study examines how powder recycling,

  19. The preparation and properties of glass powder reinforced epoxy resin

    Microsoft Academic Search

    Haifeng Wang; Wenjue Han; Haibing Tian; Yimin Wang

    2005-01-01

    A sealing composites were prepared by mixing superfine glass powder and epoxy resin. The effect of active agent (stearate) on glass powder size and size distribution and the effect of surface treatment of the glass powder on the microstructure and the mechanical properties of glass powder\\/epoxy composites were investigated. Glass powder size was measured using a laser particle size analyzer.

  20. Slip casting and nitridation of silicon powder

    NASA Technical Reports Server (NTRS)

    Seiko, Y.

    1985-01-01

    Powdered Silicon was slip-cast with a CaSO4 x 0.5H2O mold and nitrided in a N atm. containing 0 or 5 vol. % H at 1000 to 1420 deg. To remove the castings, the modeling faces were coated successively with an aq. salt soap and powdered cellulose containing Na alginate, and thus prevented the sticking problem.

  1. In-line powder coating of pultrusions

    SciTech Connect

    Spoo, K. [Owens-Corning, Granville, OH (United States); Smith, G. [Owens-Corning, Hazleton, PA (United States)

    1996-11-01

    This paper discusses the pros and cons of an in-line powder coating process that applies an acrylic modified polyurethane powder to pultruded window lineals. The system applies the finish to the pultruded part downstream from the pultrusion die. Capital costs, direct costs, and mechanics of the process are discussed.

  2. Electrical Resistivity of Metal Powder Aggregates

    Microsoft Academic Search

    J. M. Montes; F. G. Cuevas; J. Cintas

    2007-01-01

    An equation for calculating the electrical resistivity of a compressed powder mass, consisting of oxide-coated metal particles, has been derived. In addition to the intrinsic interest of the problem, the proposed equation is useful for describing the very early stages of electrical sintering processes. The problem is approached in a new way, relating the actual powder system to an equivalent

  3. Numerical Simulation of Aerated Powder Consolidation1

    E-print Network

    will slowly escape by diffusing through the material. The corresponding uneven gas pressure distribution properties. Over time the excess air diffuses through the powder and eventually escapes through the top systems for the vertical conical bunker. The height of the column of powder of time ¡ is denoted

  4. Process for the synthesis of iron powder

    Microsoft Academic Search

    Welbon

    1983-01-01

    A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide

  5. Autoclave heat treatment for prealloyed powder products

    NASA Technical Reports Server (NTRS)

    Freche, J. C.; Ashbrook, R. L.

    1973-01-01

    Technique could be applied directly to loose powders as part of hot pressing process of forming them to any required shapes. This would eliminate initial extrusion step commonly applied to prealloyed powders, substantially reduce cost of forming operation, and result in optimum properties.

  6. Modeling of microwave heating of metallic powders

    Microsoft Academic Search

    V. D. Buchelnikov; D. V. Louzguine-Luzgin; A. P. Anzulevich; I. V. Bychkov; N. Yoshikawa; M. Sato; A. Inoue

    2008-01-01

    As it is known from the experiment that bulk metallic samples reflect microwaves while powdered samples can absorb such a radiation and be heated efficiently. In the present paper we investigate theoretically the mechanisms of penetration of a layer of metallic powder by microwave radiation and microwave heating of such a system.

  7. Microwave heating of conductive powder materials

    Microsoft Academic Search

    K. I. Rybakov; V. E. Semenov; S. V. Egorov; A. G. Eremeev; I. V. Plotnikov; Yu. V. Bykov

    2006-01-01

    In recent years, a considerable interest has been drawn to microwave heating of powder metals and other electrically conductive materials. In this paper a consistent formulation describing the absorption of microwaves in electrically conductive materials under different microwave heating conditions is developed. A special case when conductive powder particles are surrounded by insulating oxide layers is investigated in detail using

  8. Thermal plasma chemical synthesis of powders

    SciTech Connect

    Vogt, G.J.; Newkirk, L.R.

    1985-01-01

    Thermal plasma processing has been increasingly used to synthesize submicron powders of high-purity ceramics and metals. The high temperatures generated with the plasma provide a vapor phase reaction zone for elements with high boiling points and refractory materials. An overview is presented on the general plasma technology used in synthesis and on the properties of plasma powders.

  9. Modeling nonelectrostatic and electrostatic powder coating

    Microsoft Academic Search

    Shantanu Yousuf; Sheryl A. Barringer

    2007-01-01

    The effect of particle size, density, charge and air velocity on transfer efficiency, evenness and separation of mixtures during powder coating was investigated using modeling and experimentation. Electrostatic and nonelectrostatic coating was tested using 28, 234 and 342?m NaCl and 195?m starch powders. Transfer efficiency increased as particle size, density or charge increased or as air velocity decreased. Evenness increased

  10. Physical and dielectric properties of pharmaceutical powders

    Microsoft Academic Search

    C. M McLoughlin; W. A. M McMinn; T. R. A Magee

    2003-01-01

    The limited availability of published physical and dielectric property data for pharmaceutical powders hinders the design of processing systems, particularly dryers. In this study, the physical properties (solubility and boiling point) and dielectric properties, in terms of temperature rise, dielectric constant, and dielectric loss factor, of selected pharmaceutical powders were measured. The pharmaceutical actives, paracetamol and aspirin, and selected common

  11. Powder Metallurgy Composite Materials Strengthened with Fibers

    Microsoft Academic Search

    Suren G. Agbalyan

    2001-01-01

    The extrusion dynamics of high-strength powder metallurgy composite materials was studied. The extrusion parameters for porous compacts of copper fibers and Cu ? Mo composites were optimized. It was shown that orientation of fibers is possible only when they are sufficiently widely dispersed in the powder matrix and also when the fiber length is much greater than its diameter l

  12. Insolubility of milk powder products A minireview

    E-print Network

    Boyer, Edmond

    of milk, at the beginning of the evaporation process, the whey proteins change their conformationReview Insolubility of milk powder products ­ A minireview Alan J. BALDWIN* Fonterra Research Abstract ­ In this paper, the formation of insolubility in milk powder is described, and the factors

  13. Wet powder seal for gas containment

    DOEpatents

    Stang, Louis G. (Sayville, NY)

    1982-01-01

    A gas seal is formed by a compact layer of an insoluble powder and liquid filling the fine interstices of that layer. The smaller the particle size of the selected powder, such as sand or talc, the finer will be the interstices or capillary spaces in the layer and the greater will be the resulting sealing capacity, i.e., the gas pressure differential which the wet powder layer can withstand. Such wet powder seal is useful in constructing underground gas reservoirs or storage cavities for nuclear wastes as well as stopping leaks in gas mains buried under ground or situated under water. The sealing capacity of the wet powder seal can be augmented by the hydrostatic head of a liquid body established over the seal.

  14. Nanostructured GGG powders via gel combustion

    NASA Astrophysics Data System (ADS)

    Li, Xianxue; Hu, Zhang-Gui; Li, Jiangtao

    2007-03-01

    Polycrystalline nano-sized gadolinium gallium garnet (Gd3Ga5O12, GGG) powders were synthesized via a gel combustion method from a mixed solution of Ga(NO3)3, Gd(NO3)3 and citric acid. The evolution of phase composition and micro-structure of the powders were characterized by X-ray powder diffraction, thermogravimetry/differential thermal analysis and scanning electron microscopy. Well-crystallized, single phase GGG nano-sized powders could be obtained at the calcining temperature as low as 750 °C for 2 h. No any intermediate phases formed during the calcining process. The resulting powders were well dispersed and had a relatively narrow size distribution with an average particle size of approximately 30-50 nm.

  15. Dense silica coatings on ceramic powder particles

    SciTech Connect

    Opitz, J.F.A.; Mayr, W. [Philips GmbH Forschungslaboratorien, Aachen (Germany)

    1995-09-01

    Dense silica coatings on the surface of inorganic powders particles are prepared by the hydrolysis of tetraethoxysilane (TEOS) in alcoholic suspensions. In a first reaction step, the TEOS is pre-hydrolysed in acidic solution and afterwards, a suspension of powder particles in this reaction solution is treated with ammonia which results in a dense silica coating of typically 10 - 100 nm thickness. Different luminescent powders which are used in the manufacture of cathode-ray tubes or fluorescent lamps have been coated by this procedure. The silica coating forms a transparent layer and the suspension properties of the coated powders are determined by the silica layer. The silica coating also protects sulfidic luminescent powders from being attacked by oxidizing agents like dichromate ions which are used in the suspension formulations for TV tube fabrication.

  16. Protein Inhalation Powders: Spray Drying vs Spray Freeze Drying

    Microsoft Academic Search

    Yuh-Fun Maa; Phuong-Anh Nguyen; Theresa Sweeney; Steven J. Shire; Chung C. Hsu

    1999-01-01

    Purpose. To develop a new technique, spray freeze drying, for preparing protein aerosol powders. Also, to compare the spray freeze-dried powders with spray-dried powders in terms of physical properties and aerosol performance.

  17. 21 CFR 524.1005 - Furazolidone aerosol powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...false Furazolidone aerosol powder. 524.1005 Section 524...1005 Furazolidone aerosol powder. (a) Specifications...affected area and apply only enough powder to impart a light yellow color...lacerations, and following firing (heat or electrocautery)....

  18. 21 CFR 524.1005 - Furazolidone aerosol powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...false Furazolidone aerosol powder. 524.1005 Section 524...1005 Furazolidone aerosol powder. (a) Specifications...affected area and apply only enough powder to impart a light yellow color...lacerations, and following firing (heat or electrocautery)....

  19. 21 CFR 524.1005 - Furazolidone aerosol powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...false Furazolidone aerosol powder. 524.1005 Section 524...1005 Furazolidone aerosol powder. (a) Specifications...affected area and apply only enough powder to impart a light yellow color...lacerations, and following firing (heat or electrocautery)....

  20. 30 CFR 75.1101-18 - Dry powder requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Resources 1 2010-07-01 2010-07-01 false Dry powder requirements. 75.1101-18 Section...COAL MINES Fire Protection § 75.1101-18 Dry powder requirements. Each dry powder chemical system shall contain the...

  1. 30 CFR 75.1101-18 - Dry powder requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Resources 1 2011-07-01 2011-07-01 false Dry powder requirements. 75.1101-18 Section...COAL MINES Fire Protection § 75.1101-18 Dry powder requirements. Each dry powder chemical system shall contain the...

  2. EFEITO DE NUTRIENTES COMBINADOS COM INDUTORES DE RESISTÊNCIA NA PROTEÇÃO CONTRA A VASSOURA-DE-BRUXA NO CACAUEIRO Effect of nutrients combined with inducers of resistance on the protection of cocoa seedlings against witches broom

    Microsoft Academic Search

    Iris Lettiere; Socorro Santos da Silva; Mário Lúcio; Vilela de Resende; Pedro Martins; Ribeiro Júnior; João de Cássia; Fabrício Rabelo Camilo; Juliana C. Baptista; Sônia Maria de Lima Salgado

    Aiming at improving the level of induction of resistance in cocoa, various nutrients, acibenzolar-S-methyl (ASM) and their combination were tested on cocoa seedlings, clone SIC-23, 30 days before inoculation. The commercial products Supa-potássio (potassium silicate), Hortifós PK (potassium phosphite) and Broadacre Mn (manganese sulfate) were sprayed at doses of 2.5, 5.0 mL and 10.0 mL per liter of water, combined

  3. Deagglomeration of dry powder pharmaceutical aerosols.

    PubMed

    Voss, Austin; Finlay, Warren H

    2002-11-01

    The effect of turbulence and mechanical impaction on dry powder aerosol deaggregation was tested using a novel powder deagglomeration rig, with fine particle fraction (FPF(ED<5.6 microm)), defined here as particles sized smaller than 5.6 microm, measured using an Anderson inertial impactor. Powder from GlaxoSmithKline Ventodisks was deaggregated either using turbulence generated with a ring of impinging jets, or by impacting the powder on bars of a wire mesh. This deaggregation was compared with deaggregation achieved with the GlaxoSmithKline Diskhaler. The turbulence levels in the test rig and at the exit of the Diskhaler were quantified using laser Doppler velocimetry (LDV). In addition, the Ventodisk powder's auto-adhesion properties were altered by introducing the powder into a high humidity environment (25 degrees C and 25% R.H.) and then deagglomerated by both the rig (using turbulence as the primary deagglomeration mechanism) and the Diskhaler. Fine particle fractions were found to increase from 13 to 24% as the level of turbulence in the rig was increased. However, fine particle fractions found with the Diskhaler were 35%. Turbulence levels found in the rig at the highest jet flow rate were significantly higher than that at the outlet of the Diskhaler, leading to the conclusion that turbulence is not the only method of deaggregation in this inhaler. The humidified powders were significantly more difficult to deaggregate, giving a FPF(ED<5.6 microm) of 9% when using the rig and 15% when using the Diskhaler. Fine particle fractions produced when deagglomerating the powder with the wire meshes were similar to those produced without a mesh, showing that mechanical impaction had little effect. The results underline the utility of having a rig that can explore the ability of a powder to deagglomerate with controlled variations in the deaggregation forces. PMID:12429458

  4. Shock compression response of nanoiron powder compact

    NASA Astrophysics Data System (ADS)

    Dai, Chengda; Eakins, Daniel; Thadhani, Naresh; Liu, J. Ping

    2007-02-01

    The shock compression response of nano-Fe powder (˜25nm) pressed to ˜35% theoretical maximum density was determined based on shock stress and wave velocity measurements using piezoelectric stress gauges. The obtained data show a discontinuity in shock wave velocity plotted against particle velocity and an inflexion in specific volume from compression to expansion with increasing shock stress. It is found that the Hugoniot of 25nm Fe powder cannot be fully described using analytical models that are otherwise capable of predicting the Hugoniot of micron-sized powder or highly porous materials.

  5. Electrical Resistivity of Metal Powder Aggregates

    NASA Astrophysics Data System (ADS)

    Montes, J. M.; Cuevas, F. G.; Cintas, J.

    2007-12-01

    An equation for calculating the electrical resistivity of a compressed powder mass, consisting of oxide-coated metal particles, has been derived. In addition to the intrinsic interest of the problem, the proposed equation is useful for describing the very early stages of electrical sintering processes. The problem is approached in a new way, relating the actual powder system to an equivalent system consisting of deforming spheres in a simple cubic packing, which is much easier to examine. The proposed equation was experimentally verified from measurements of the electrical resistivity for aluminum, bronze, iron, and nickel powders under pressure. The consistency between theoretical predictions and experimental results was reasonably good in all cases.

  6. Microwave heating of conductive powder materials

    NASA Astrophysics Data System (ADS)

    Rybakov, K. I.; Semenov, V. E.; Egorov, S. V.; Eremeev, A. G.; Plotnikov, I. V.; Bykov, Yu. V.

    2006-01-01

    In recent years, a considerable interest has been drawn to microwave heating of powder metals and other electrically conductive materials. In this paper a consistent formulation describing the absorption of microwaves in electrically conductive materials under different microwave heating conditions is developed. A special case when conductive powder particles are surrounded by insulating oxide layers is investigated in detail using the effective-medium approximation. The conditions giving rise to skin effect governed, volumetric, and localized microwave heating are analyzed. Experimental observations of different microwave heating regimes in silicon, iron, and copper powder compacts are in general agreement with the theoretical model.

  7. Pulmonary drug delivery by powder aerosols.

    PubMed

    Yang, Michael Yifei; Chan, John Gar Yan; Chan, Hak-Kim

    2014-11-10

    The efficacy of pharmaceutical aerosols relates to its deposition in the clinically relevant regions of the lungs, which can be assessed by in vivo lung deposition studies. Dry powder formulations are popular as devices are portable and aerosolisation does not require a propellant. Over the years, key advancements in dry powder formulation, device design and our understanding on the mechanics of inhaled pharmaceutical aerosol have opened up new opportunities in treatment of diseases through pulmonary drug delivery. This review covers these advancements and future directions for inhaled dry powder aerosols. PMID:24818765

  8. Analysis of powder diffraction data

    SciTech Connect

    Cooper, M.J.

    1982-01-01

    A comparison has been carried out between the results of analyses of several sets of neutron powder diffraction data using three different methods: the Rietveld method (H.M. Rietveld, Acta. Cryst. 2, 151-152 (1967): J. Appl. Cryst. 2, 65-71 (1969), a modification of the Rietveld method to include off-diagonal terms in the weight matrix (C.P. Clarke and J.S. Rollett, Acta. Cryst. In the press) and the SCRAP method, which involves the estimation of observed Bragg intensities (M.J. Cooper, K.D. Rouse and M. Sakata, Z. Krist. In the press). Two simulations have also been carried out to demonstrate the way in which the results can differ in more extreme cases. This study has confirmed that the values of the estimated standard deviations given by the Rietveld method are not reliable and that, of the methods considered, only the SCRAP method will in general give reliable values for the estimated standard deviations of the structural parameters.

  9. Continuous production of titanium powder

    SciTech Connect

    Gerdemann, Stephen J.; Oden, Laurence L.; White, Jack C.

    1997-01-01

    Although incremental improvements have been made to the Kroll process since its inception in 1948, the process in use today remains essentially the same batch process developed by Dr. Kroll and perfected by the U.S. Bureau of Mines. In this process, titanium tetrachloride (TiCl4) is reduced by magnesium to produce titanium metal. There are two major limitations to the Kroll process: (1) it is a batch process; and (2) the reduction of TiCl4 proceeds so rapidly that the sponge formed is an interlocking dendritic mass with inclusions of magnesium, magnesium salts and titanium subchloride that must undergo several purification steps before the metal is suitable for use. The Albany Research Center (ARC), formerly the U.S. Bureau of Mines, has investigated a new, continuous titanium metal production process in which a titanium powder is produced in a bath of molten salt. In this process, the rate of the reduction reaction was slowed and controlled by diluting the reactants with molten chloride salts. The diluted reactant streams were combined in a continuous stirred tank reactor, operated much like a crystallizer. New titanium metal forms on the already present small Ti particles. When the Ti particles become too large to remain suspended in solution, they fall to the bottom of the reactor and are removed. Initial experiments show promise but problems remain in obtaining the required purity and uniform particle size.

  10. Laminated composite of magnetic alloy powder and ceramic powder and process for making same

    DOEpatents

    Moorhead, Arthur J. (Knoxville, TN); Kim, Hyoun-Ee (Seoul, KR)

    1999-01-01

    A laminated composite structure of alternating metal powder layers, and layers formed of an inorganic bonding media powder, and a method for manufacturing same are discosed. The method includes the steps of assembling in a cavity alternating layers of a metal powder and an inorganic bonding media of a ceramic, glass, and glass-ceramic. Heat, with or without pressure, is applied to the alternating layers until the particles of the metal powder are sintered together and bonded into the laminated composite structure by the layers of sintered inorganic bonding media to form a strong composite structure. The method finds particular application in the manufacture of high performance magnets wherein the metal powder is a magnetic alloy powder.

  11. Effects of milk powders in milk chocolate.

    PubMed

    Liang, B; Hartel, R W

    2004-01-01

    The physical characteristics of milk powders used in chocolate can have significant impact on the processing conditions needed to make that chocolate and the physical and organoleptic properties of the finished product. Four milk powders with different particle characteristics (size, shape, density) and "free" milk fat levels (easily extracted with organic solvent) were evaluated for their effect on the processing conditions and characteristics of chocolates in which they were used. Many aspects of chocolate manufacture and storage (tempering conditions, melt rheology, hardness, bloom stability) were dependent on the level of free milk fat in the milk powder. However, particle characteristics of the milk powder also influenced the physical and sensory properties of the final products. PMID:14765806

  12. Screening and classification of ceramic powders

    NASA Technical Reports Server (NTRS)

    Miwa, S.

    1983-01-01

    A summary is given of the classification technology of ceramic powders. Advantages and disadvantages of the wet and dry screening and classification methods are discussed. Improvements of wind force screening devices are described.

  13. Magnesium Powder Metallurgy: Process and Materials Opportunities

    NASA Astrophysics Data System (ADS)

    Bettles, Colleen J.

    2008-06-01

    The major efforts in magnesium alloy development for automotive applications have concentrated on creep resistant alloys produced by permanent mould and high-pressure die casting routes. While large components, such as crankcases, will never be produced by powder metallurgy, there are smaller components in and around the powertrain which could be fabricated from powder precursors. This article will explore the potential of some of the more recent powder compaction developments, and discuss the alloy development strategies that emerge for magnesium-based components as a consequence of these process developments. In particular, the viability of direct powder extrusion of semi-finished product, using conventional extrusion or equal channel angular processing, combined with T6 heat treatments, will be considered.

  14. Advances in beryllium powder consolidation simulation

    SciTech Connect

    Reardon, B.J.

    1998-12-01

    A fuzzy logic based multiobjective genetic algorithm (GA) is introduced and the algorithm is used to optimize micromechanical densification modeling parameters for warm isopressed beryllium powder, HIPed copper powder and CIPed/sintered and HIPed tantalum powder. In addition to optimizing the main model parameters using the experimental data points as objective functions, the GA provides a quantitative measure of the sensitivity of the model to each parameter, estimates the mean particle size of the powder, and determines the smoothing factors for the transition between stage 1 and stage 2 densification. While the GA does not provide a sensitivity analysis in the strictest sense, and is highly stochastic in nature, this method is reliable and reproducible in optimizing parameters given any size data set and determining the impact on the model of slight variations in each parameter.

  15. The basics of powder lubrication in high-temperature powder-lubricated dampers

    Microsoft Academic Search

    H. Heshmat; J. F. Walton

    1993-01-01

    The objective of this investigation is to develop a novel powder-lubricated rotor bearing system damper concept for use in high-temperature, high-speed rotating machinery such as advanced aircraft gas turbine engines. The approach discussed herein consists of replacing a conventional oil lubrication or frictional damper system with a powder lubrication system that uses the process particulates or externally fed powder lubricant.

  16. [Use of powder metallurgy for development of implants of Co-Cr-Mo alloy powder].

    PubMed

    Dabrowski, J R

    2001-04-01

    This paper discusses the application of powder metallurgy for the development of porous implantation materials. Powders obtained from Co-Cr-Mo alloy with different carbon content by water spraying and grinding, have been investigated. Cold pressing and rotary re-pressing methods were used for compressing the powder. It was found that the sintered materials obtained from water spraying have the most advantageous properties. PMID:11388037

  17. Research of minimum ignition energy for nano Titanium powder and nano Iron powder

    Microsoft Academic Search

    Hong-Chun Wu; Ri-Cheng Chang; Hsiao-Chi Hsiao

    2009-01-01

    Most manufacturing units that process nanoparticles face a threat from fires and explosions. This study examines Ti powders with diameters of 3?m, 8?m, 20?m, 45?m, 35nm, 75nm, and 100nm, and Fe powders with diameters of 150?m, 15nm, 35nm, and 65nm. The goal of our study was to measure the minimum ignition energy (MIE) for each of the above mentioned powders

  18. Fine PMN powders prepared from nitrate solutions

    Microsoft Academic Search

    Y. Yoshikawa

    1994-01-01

    A partial coprecipitation method was developed in order to synthesize lead magnesium niobate Pb(Mg1\\/3Nb(2\\/3))O3 (PMN) powders from nitrate solutions. To obtain a niobium precursor compatible with the chemical routes, peroxo-niobium complex solutions were prepared by dissolving hydrated niobia precipitates in a dilute nitric acid solution with hydrogen peroxide. Fine PMN powders were prepared from these nitrate solutions by two-stage hydrolysis.

  19. Relative flow rates of explosive powders

    SciTech Connect

    Willson, V.P.

    1988-05-31

    A study was performed to determine the relative flow rates of various explosive powders and evaluate their adaptability for use in automated dispensing systems. Results showed that PBX 9407, LX-15, RX-26-BH, and HNAB are potential candidates for use in these systems. It was also shown that powders with graphite and stearate additives generated the least amount of static and were the easiest to handle.

  20. Microemulsion Synthesis of Nanoparticle PZT Powder

    Microsoft Academic Search

    M. Amiriyan; Z. A. Nemati; M. S. Rahmanifar; S. Ramesh; S. Meenaloshini; R. Tolouei

    2011-01-01

    Nanocrystalline lead zirconate titanate (PZT) powders have been synthesized using microemulsion processing route. Microemulsion is one of the major processing techniques to synthesize a nanosize, homogenous, and almost agglomerate free ceramic powders. The ternary microemulsion system is consisted of cyclohexane as the oil phase, Triton X100 as the nonionic surfactant phase, and an aqueous phase containing 0.619 M Pb2+, 0.325

  1. Synthesis and processing of monosized oxide powders

    DOEpatents

    Barringer, E.A.; Fegley, M.B. Jr.; Bowen, H.K.

    1985-09-24

    Uniform-size, high-purity, spherical oxide powders are formed by hydrolysis of alkoxide precursors in dilute alcoholic solutions. Under controlled conditions (concentrations of 0.03 to 0.2 M alkoxide and 0.2 to 1.5 M water, for example) oxide particles on the order of about 0.05 to 0.7 microns can be produced. Methods of doping such powders and forming sinterable compacts are also disclosed. 6 figs.

  2. Synthesis and processing of monosized oxide powders

    DOEpatents

    Barringer, Eric A. (Waltham, MA); Fegley, Jr., M. Bruce (Waban, MA); Bowen, H. Kent (Belmont, MA)

    1985-01-01

    Uniform-size, high-purity, spherical oxide powders are formed by hydrolysis of alkoxide precursors in dilute alcoholic solutions. Under controlled conditions (concentrations of 0.03 to 0.2 M alkoxide and 0.2 to 1.5 M water, for example) oxide particles on the order of about 0.05 to 0.7 micron can be produced. Methods of doping such powders and forming sinterable compacts are also disclosed.

  3. Electrical Resistivity of Metal Powder Aggregates

    Microsoft Academic Search

    J. M. Montes; F. G. Cuevas; J. Cintas

    2007-01-01

    An equation for calculating the electrical resistivity of a compressed powder mass, consisting of oxide-coated metal particles,\\u000a has been derived. In addition to the intrinsic interest of the problem, the proposed equation is useful for describing the\\u000a very early stages of electrical sintering processes. The problem is approached in a new way, relating the actual powder system\\u000a to an equivalent

  4. Adjustable Powder Injector For Vacuum Plasma Sprayer

    NASA Technical Reports Server (NTRS)

    Burns, D. H.; Woodford, W. H.; Mckechnie, T. N.; Mcferrin, D. C.; Davis, W. M.; Beason, G. P., Jr.

    1993-01-01

    Attachment for plasma spray gun provides four degrees of freedom for adjustment of position and orientation at which powder injected externally into plasma flame. Manipulator provides for adjustment of pitch angle of injection tube: set to inject powder at any angle ranging from perpendicular to parallel to cylindrical axis. Scribed lines on extension bar and manipulator indicate pitch angle of extension tube. Collar changed to adapt injector to different gun.

  5. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1994-01-01

    Free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be used

  6. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1994-01-01

    A free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be

  7. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1992-01-01

    Free flowing, conformable powder-like mix of silica particles and a phase change material (p.c.m.) is disclosed. The silica particles have a critical size of about 7.times.10.sup.-3 to about 7.times.10.sup.-2 microns and the pcm must be added to the silica in an amount of 80 wt. % or less pcm per combined weight of silica and pcm. The powder-like mix can

  8. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1993-01-01

    Free flowing, conformable powder-like mix of silica particles and a phase change material (p.c.m.) is disclosed. The silica particles have a critical size of about 7.times.10.sup.-3 to about 7.times.10.sup.-2 microns and the pcm must be added to the silica in an amount of 80 wt. % or less pcm per combined weight of silica and pcm. The powder-like mix can

  9. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1995-01-01

    A free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be

  10. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit (Knoxville, TN); Williams, Robert K. (Knoxville, TN)

    2001-01-01

    A biaxially textured alloy article comprises Ni powder and at least one powder selected from the group consisting of Cr, W, V, Mo, Cu, Al, Ce, YSZ, Y, Rare Earths, (RE), MgO, CeO.sub.2, and Y.sub.2 O.sub.3 ; compacted and heat treated, then rapidly recrystallized to produce a biaxial texture on the article. In some embodiments the alloy article further comprises electromagnetic or electro-optical devices and possesses superconducting properties.

  11. Microemulsion Synthesis of Nanoparticle PZT Powder

    NASA Astrophysics Data System (ADS)

    Amiriyan, M.; Nemati, Z. A.; Rahmanifar, M. S.; Ramesh, S.; Meenaloshini, S.; Tolouei, R.

    2011-01-01

    Nanocrystalline lead zirconate titanate (PZT) powders have been synthesized using microemulsion processing route. Microemulsion is one of the major processing techniques to synthesize a nanosize, homogenous, and almost agglomerate free ceramic powders. The ternary microemulsion system is consisted of cyclohexane as the oil phase, Triton X100 as the nonionic surfactant phase, and an aqueous phase containing 0.619 M Pb2+, 0.325 M Zr4+, and 0.3 M Ti4+, representing a Pb2+: Zr4+: Ti4+ molar ratio of 1:0.52:0.48. The ratio of these cations has been adjusted using Inductively Coupled Plasma (ICP) technique. After coprecipitation of metallic hydroxides by adding ammonia solution in microemulsion system, the PZT precursor was obtained. PZT powders have been prepared upon calcination of precursor at 800° C. Prepared powders was characterised using techniques such as X-ray diffraction, differential thermal analysis, and scanning electron microscopy. The characteristics of microemulsion processed powder is discussed, with emphasis on the presence of nano scaled PZT powder with a composition near to morphotropic phase boundary (MPB) without formation of any intermediate phases.

  12. Ti Multicomponent Alloy Bulks by Powder Metallurgy

    NASA Astrophysics Data System (ADS)

    Zhang, Kuibao; Wen, Guanjun; Dai, Hongchuan; Teng, Yuancheng; Li, Yuxiang

    2014-10-01

    In this study, CrCuFeMnMo0.5Ti multicomponent alloy bulks were prepared by powder metallurgy of mechanical alloying and sintering. A simple body-centered cubic (bcc) solid solution was prepared after 40 h ball milling of the raw CrCuFeMnMo0.5Ti metallic powder. Particles of the alloyed powder are in microsized structures, which are actually a soft agglomeration of lamellar grains with thicknesses less than 1 ?m. Meanwhile, the lamellar granules are consisted of nanosized grains under rigid cold welding. The 80-h ball-milled powder was consolidated by cold pressing and subsequent sintering at 800°C. The observed main phase in the consolidated sample after milling for 80 h is still a bcc solid solution. The solidified sample of 80-h ball-milled powder exhibits a Vickers hardness of 468 HV, which is much higher than 171 HV of the counterpart prepared from the raw metallic powder.

  13. The application of PLC in electrostatic powder sprayer

    Microsoft Academic Search

    Caiqiao Wei; Tianyan Ma; Deping Zhang

    2011-01-01

    In order to prevent the glass from scratching and mildewing in storage and transportation, the anti-mildew powder should be added between the glass. For the demand of the powder spraying , the electrostatic powder sprayer control system based on PLC was developed. Spraying constant powder for the middle -part glass of variable thickness realized by controlling two frequency converters respectively.

  14. Dispersion of alkoxide-hydrolysed zirconia powders in aqueous suspensions

    Microsoft Academic Search

    Kwang-Lung Lin; Huey-Chang Wang

    1989-01-01

    It is always desirable to control the agglomeration of ceramic powders in ceramic processing, as this strongly affects the sintering behaviour [1, 2] of the powders. A recent wet chemical process deserves attention because of the possibility of achieving ultrafine, high-purity monodispersed ceramic powders [3, 4] and the possibility of the powders obtained to yield ultrastructure [5]. During wet chemical

  15. Modelling Dry Powder Inhaler Operation with the Discrete Element

    E-print Network

    Frey, Pascal

    Modelling Dry Powder Inhaler Operation with the Discrete Element Method Robert James Tuley Powder Inhaler Operation with the Discrete Element Method Robert James Tuley Abstract Dry powder inhalers is known about their internal operation: the process of fluidising a powder dose into an inhalation airflow

  16. Lining of light metals with hard powders using shot peening

    Microsoft Academic Search

    Yasunori Harada; Ken-ichiro Mori; Seijiro Maki

    2002-01-01

    A lining of light metals with hard powders using shot peening was carried out. The hard powders are bonded to the surface of the workpieces due to the collision with many shots. To fix the hard powders on the surface of the workpiece, the powder is placed on the uneven surface, and the surface is covered with a pure aluminium

  17. January 2013 BEE CULTURE 23 Revisiting Powdered Sugar For

    E-print Network

    Delaplane, Keith S.

    January 2013 BEE CULTURE 23 Revisiting Powdered Sugar For Varroa Control On Honey Bees (Apis dust bees with powder sugar as a means of removing mites. Dusting with powder sugar was also gaining conducted a study which examined the efficacy of powder sugar and found it did not help in controlling

  18. Spontaneous cocoa bean fermentation carried out in a novel-design stainless steel tank: influence on the dynamics of microbial populations and physical-chemical properties.

    PubMed

    de Melo Pereira, Gilberto Vinícius; Magalhães, Karina Teixeira; de Almeida, Euziclei Gonzaga; da Silva Coelho, Irene; Schwan, Rosane Freitas

    2013-02-01

    Spontaneous cocoa bean fermentations carried out in a novel-design 40-kg-capacity stainless steel tank (SST) was studied in parallel to traditional Brazilian methods of fermentation in wooden boxes (40-kg-capacity wooden boxes (WB1) and 600-kg-capacity wooden boxes (WB2)) using a multiphasic approach that entailed culture-dependent and -independent microbiological analyses of fermenting cocoa bean pulp samples and target metabolite analyses of both cocoa pulp and cotyledons. Both microbiological approaches revealed that the dominant species of major physiological roles were the same for fermentations in SST, relative to boxes. These species consisted of Saccharomyces cerevisiae and Hanseniaspora sp. in the yeast group; Lactobacillus fermentum and L. plantarum in the lactic acid bacteria (LAB) group; Acetobacter tropicalis belonging to the acetic acid bacteria (AAB) group; and Bacillus subtilis in the Bacillaceae family. A greater diversity of bacteria and non-Saccharomyces yeasts was observed in box fermentations. Additionally, a potentially novel AAB belonging to the genus Asaia was isolated during fermentation in WB1. Cluster analysis of the rRNA genes-PCR-DGGE profiles revealed a more complex picture of the box samples, indicating that bacterial and yeast ecology were fermentation-specific processes (wooden boxes vs. SST). The profile of carbohydrate consumption and fermentation products in the pulp and beans showed similar trends during both fermentation processes. However, the yeast-AAB-mediated conversion of carbohydrates into ethanol, and subsequent conversion of ethanol into acetic acid, was achieved with greater efficiency in SST, while temperatures were generally higher during fermentation in wooden boxes. With further refinements, the SST model may be useful in designing novel bioreactors for the optimisation of cocoa fermentation with starter cultures. PMID:23279821

  19. Slip casting nano-particle powders for making transparent ceramics

    DOEpatents

    Kuntz, Joshua D. (Livermore, CA); Soules, Thomas F. (Livermore, CA); Landingham, Richard Lee (Livermore, CA); Hollingsworth, Joel P. (Oakland, CA)

    2011-04-12

    A method of making a transparent ceramic including the steps of providing nano-ceramic powders in a processed or unprocessed form, mixing the powders with de-ionized water, the step of mixing the powders with de-ionized water producing a slurry, sonifing the slurry to completely wet the powder and suspend the powder in the de-ionized water, separating very fine particles from the slurry, molding the slurry, and curing the slurry to produce the transparent ceramic.

  20. Reduction and carburization in iron powder production at the brovary powder metallurgy factory

    Microsoft Academic Search

    A. F. Zhornyak; Yu. I. Timchenko; I. M. Fedorenko

    1968-01-01

    1.Study of the reduction and carburization kinetics in iron powder furnaces exposed and led to the removal of several shortcomings in these units.2.A method has been developed for reducing the charge in porous drip pans made from rolled powders. Trials using this method showed that the porous drip pans improve heat transfer and gas permeability of the charge and so

  1. Polymer powders for selective laser sintering (SLS)

    NASA Astrophysics Data System (ADS)

    Schmid, Manfred; Amado, Antonio; Wegener, Konrad

    2015-05-01

    Selective Laser Sintering (SLS) is close to be accepted as a production technique (Additive Manufacturing). However, one problem limiting employment of SLS for additive manufacturing in a wide-ranging industrial scope is the narrow variety of applicable polymers. The commonly applied SLS powder to date is polyamide 12 (PA 12). PA 12 or ccompounds of PA 12 (dry blends) are approximately 90 % of complete industrial consumption. The remaining small quantity is distributed on polyamide 11 (PA11) and some other `exotic' polymers (TPU, PEBA, P(E)EK). Industry is awaiting commodity polymers like polypropylene (PP) or polyethylene (PE) crucial to open new market segments. But several approaches launching those polymers failed. But what are the reasons for the difficulties in developing new SLS powders? The contribution is to answer this and highlights the combination of intrinsic and extrinsic polymer properties necessary to generate a polymer powder promising for SLS application. Particle shape, powder distribution, thermal, rheological and optical requirements must be considered and only a particularly controlled property combination leads to successful SLS implementation. Thermal behavior, particle shape and -distribution is discussed in detail, although the other properties can't be disregarded for providing new commercially successful SLS powder finally.

  2. Drop penetration into porous powder beds.

    PubMed

    Hapgood, Karen P; Litster, James D; Biggs, Simon R; Howes, Tony

    2002-09-15

    The kinetics of drop penetration were studied by filming single drops of several different fluids (water, PEG200, PEG600, and HPC solutions) as they penetrated into loosely packed beds of glass ballotini, lactose, zinc oxide, and titanium dioxide powders. Measured times ranged from 0.45 to 126 s and depended on the powder particle size, viscosity, surface tensions, and contact angle. The experimental drop penetration times were compared to existing theoretical predictions by M. Denesuk et al. (J. Colloid Interface Sci.158, 114, 1993) and S. Middleman ("Modeling Axisymmetric Flows: Dynamics of Films, Jets, and Drops," Academic Press, San Diego, 1995) but did not agree. Loosely packed powder beds tend to have a heterogeneous bed structure containing large macrovoids which do not participate in liquid flow but are included implicitly in the existing approach to estimating powder pore size. A new two-phase model was proposed where the total volume of the macrovoids was assumed to be the difference between the bed porosity and the tap porosity. A new parameter, the effective porosity epsilon(eff), was defined as the tap porosity multiplied by the fraction of pores that terminate at a macrovoid and are effectively blocked pores. The improved drop penetration model was much more successful at estimating the drop penetration time on all powders and the predicted times were generally within an order of magnitude of the experimental results. PMID:16290866

  3. A hydroxycarbonate route to superconductor precursor powders

    SciTech Connect

    Voigt, J.A.; Bunker, B.C.; Doughty, D.H.; Lamppa, D.L.; Kimball, K.M.

    1987-01-01

    A precipitation process is described for the preparation of powders that can be thermally decomposed to form high critical temperature superconductors such as YBa/sub 2/Cu/sub 3/O/sub 7/. In the process, a cationic solution (a concentrated chloride or nitrate solution) is instantaneously mixed with an anionic solution (a mixture of tetramethylammonium hydroxide and carbonate) to produce a metal-hydroxycarbonate precipitate having the metal stoichiometry of the desired superconducting oxide. The calcining and sintering of the precipitates is critical in controlling the structural integrity and morphology of the superconducting cermaics made from the chem-prep powders, as well as controlling superconducting properties. Under appropriate conditions, high density (>95%) materials that exhibit good superconducting characteristics can be prepared with the chem-prep powders. 6 refs., 3 figs.

  4. Dry powder coating of pharmaceuticals: a review.

    PubMed

    Sauer, Dorothea; Cerea, Matteo; DiNunzio, James; McGinity, James

    2013-12-01

    Over the last half century, film coating technology has evolved significantly in terms of compositions and manufacturing processes, allowing for greater functionality, flexibility and efficiency. Driven by a combination of cost considerations and functionality, a range of dry powder coating technologies have been developed in both academic and industrial settings. These technologies can be generally classified into three major types based on the layer formation process: liquid assisted, thermal adhesion and electrostatic. In addition to specific manufacturing processes that must be implemented to achieve the desired product attributes, many of these techniques also require the use of novel excipients and specific formulations to provide acceptable manufacturability. This review summarizes the current dry powder coating technologies and highlights their industrial applicability with publicly disclosed case studies. Commentary on the future directions of dry powder coating is also provided. PMID:23428881

  5. Nitridation of chromium powder in ammonia atmosphere

    NASA Astrophysics Data System (ADS)

    Li, Ling; Zhen, Qiang; Li, Rong

    2015-03-01

    CrN powder was synthesized by nitriding Cr metal in ammonia gas flow, and its chemical reaction mechanism and nitridation process were studied. Through thermodynamic calculations, the Cr-N-O predominance diagrams were constructed for different temperatures. Chromium nitride formed at 7002-1200°C under relatively higher nitrogen and lower oxygen partial pressures. Phases in the products were then investigated using X-ray diffraction (XRD), and the Cr2N content varied with reaction temperature and holding time. The results indicate that the Cr metal powder nitridation process can be explained by a diffusion model. Further, Cr2N formed as an intermediate product because of an incomplete reaction, which was observed by high-resolution transmission electron microscopy (HRTEM). After nitriding at 1000°C for 20 h, CrN powder with an average grain size of 63 nm was obtained, and the obtained sample was analyzed by using a scanning electron microscope (SEM).

  6. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-10-21

    A strengthened, biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed, compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: Ni, Ag, Ag--Cu, Ag--Pd, Ni--Cu, Ni--V, Ni--Mo, Ni--Al, Ni--Cr--Al, Ni--W--Al, Ni--V--Al, Ni--Mo--Al, Ni--Cu--Al; and at least one fine metal oxide powder; the article having a grain size which is fine and homogeneous; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  7. [Dry powder inhalers in cystic fibrosis].

    PubMed

    Steinkamp, G

    2014-06-01

    Inhaled medications play an important role in the daily treatment of patients with cystic fibrosis (CF). The classic route of administration was nebulisation via jet nebulisers. Respiratory delivery of fluid particles should loosen the viscid respiratory secretions, making airway clearance via cough or physiotherapy more efficient. Until recently, only jet nebulisers allowed to administer high doses of aerosolised antipseudomonal antibiotics. Powder inhalers for the treatment of cystic fibrosis have recently been made available. The newly developed powders and inhalers differ considerably from conventional dry powder inhalers used for the treatment of chronic obstructive airway disease. The present article will review two inhaled antibiotics, i.?e. tobramycin and colistin, and the hyperosmotic agent mannitol, which increases the hydration of the airways. Topics are particle engineering, efficacy and tolerability results from clinical trials, as well as functional and practical aspects related to these new drugs. PMID:24664997

  8. Atomization methods for forming magnet powders

    DOEpatents

    Sellers, Charles H. (Idaho Falls, ID); Branagan, Daniel J. (Idaho Falls, ID); Hyde, Timothy A. (Idaho Falls, ID)

    2000-01-01

    The invention encompasses methods of utilizing atomization, methods for forming magnet powders, methods for forming magnets, and methods for forming bonded magnets. The invention further encompasses methods for simulating atomization conditions. In one aspect, the invention includes an atomization method for forming a magnet powder comprising: a) forming a melt comprising R.sub.2.1 Q.sub.13.9 B.sub.1, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; b) atomizing the melt to form generally spherical alloy powder granules having an internal structure comprising at least one of a substantially amorphous phase or a substantially nanocrystalline phase; and c) heat treating the alloy powder to increase an energy product of the alloy powder; after the heat treatment, the alloy powder comprising an energy product of at least 10 MGOe. In another aspect, the invention includes a magnet comprising R, Q, B, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; the magnet comprising an internal structure comprising R.sub.2.1 Q.sub.13.9 B.sub.1.

  9. Synthesis of ultrafine powders by microwave heating

    DOEpatents

    Meek, T.T.; Sheinberg, H.; Blake, R.D.

    1987-04-24

    A method of synthesizing ultrafine powders using microwaves is described. A water soluble material is dissolved in water and the resulting aqueous solution is exposed to microwaves until the water has dissolved. The resulting material is an ultrafine powder. This method can be used to make Al/sub 2/O/sub 3/, NiO /plus/ Al/sub 2/O/sub 3/ and NiO as well as a number of other materials including GaBa/sub 2/Cu/sub 3/O/sub x/. 1 tab.

  10. Removing Undesired Fine Powder From Silicon Reactor

    NASA Technical Reports Server (NTRS)

    Flagella, Robert N.

    1992-01-01

    Fluidized-bed reactor produces highly pure polycrystalline silicon particles with diameters approximately greater than 400 micrometers. Operates by pyrolysis of silane in reaction zone, which is bed of silicon seed particles fluidized by flow of silane and carrier gas. Above reaction zone, gas mixture flows rapidly enough to entrain silicon powders, but not larger seed and product particles. Entrained particles swept out of reactor. Applicable to other processes such as production of fine metal and ceramic powders where control of sizes of product needed.

  11. Alternative carriers in dry powder inhaler formulations.

    PubMed

    Rahimpour, Yahya; Kouhsoltani, Maryam; Hamishehkar, Hamed

    2014-05-01

    The aerosolization efficiency of a powder is highly dependent on carrier characteristics, such as particle size distribution, shape and surface properties. The main objective in the inhalation field is to achieve a high and reproducible pulmonary deposition. This can be provided by successful carrier selection and careful process optimization for carrier modification. Lactose is the most common and frequently used carrier in dry powder inhaler (DPI) formulations. But lactose shows some limitations in formulation with certain drugs and peptides that prohibit its usage as a carrier in DPI formulations. Here, we criticality review the most important alternative carriers to lactose with merits, demerits and applications in DPI formulations. PMID:24269834

  12. Thermal Oxidation of Aluminum Nitride Powder

    SciTech Connect

    Gu, Zheng; Edgar, James H.; Wang, Chong M.; Coffey, Dorothy

    2006-07-31

    The kinetics of the thermal oxidation of AlN powder in flowing oxygen over temperatures from 800 to 1150 C and the morphology and crystallinity of the resultant oxide were determined. The oxidation of two types of AlN powder was investigated and compared. Complex difference in the oxidation behavior was observed, probably due to their different morphology, particle size, particle size distribution, and residual impurities. Amorphous alumina formed at relatively low oxidation temperatures (800-1000 C), with a linear oxidation rate governed by interfacial reaction. Crystalline alumina formed at higher temperatures (>1000 C), and the oxidation rate was parabolic which suggested an oxidant diffusion controlled process.

  13. Random Laser Action in Semiconductor Powder

    NASA Astrophysics Data System (ADS)

    Cao, H.; Zhao, Y. G.; Ho, S. T.; Seelig, E. W.; Wang, Q. H.; Chang, R. P. H.

    1999-03-01

    We report the first observation of random laser action with coherent feedback in semiconductor powder. Since the scattering mean free path is less than the emission wavelength, recurrent light scattering arises and provides coherent feedback for lasing. Discrete lasing modes have been observed above the threshold. The dependence of the lasing threshold intensity on the excitation volume agrees with the random laser theory. Laser emission from the powder could be observed in all directions. This observation also provides direct evidence for the existence of recurrent scattering of light.

  14. Combustion characteristics of the heat pellet prepared from the Fe powders obtained by spray pyrolysis

    Microsoft Academic Search

    J. H. Kim; H. Y. Koo; S. K. Hong; J. M. Han; H. C. Jang; Y. N. Ko; Y. J. Hong; Y. C. Kang; S. H. Kang; S. B. Cho

    Fe powders for thermal batteries were prepared by reduction of iron oxide powders obtained by spray pyrolysis. The iron oxide powders prepared by spray pyrolysis had fine size, spherical shape and high surface area. The morphologies of the Fe powders were affected by the preparation temperatures of the iron oxide powders. The Fe powders obtained from the iron oxide powders

  15. Magnetic Properties of Amorphous Fe-Si-B Powder Cores Mixed with Pure Iron Powder

    NASA Astrophysics Data System (ADS)

    Kim, Hyeon-Jun; Nam, Seul Ki; Kim, Kyu-Sung; Yoon, Sung Chun; Sohn, Keun-Yong; Kim, Mi-Rae; Sul Song, Yong; Park, Won-Wook

    2012-10-01

    Amorphous Fe-Si-B alloy was prepared by melt-spinning, and then the ribbons were pulverized and ball-milled to make the amorphous powder of ˜25 µm in size. Subsequently those were mixed with pure iron powders with an average particle size of 3 µm, and 1.5 wt % water glass diluted by distilled water at the ratio of 1:2. The powder mixtures were cold compacted at 650 MPa in toroid die, and heat treated at 430-440 °C under a nitrogen atmosphere for 1 h and 30 min, respectively. The soft magnetic properties of powder core were investigated using a B-H analyzer and a flux meter at the frequency range of ˜100 kHz. The microstructure was observed using scanning electron microscope (SEM), and the density of the core was measured using the principle of Archimedes. Based on the experimental results, the amorphous powder mixed with pure iron powder showed the improved powder compactability, which resulted in the increased permeability and the reduced core loss.

  16. Improved Small-Particle Powders for Plasma Spraying

    NASA Technical Reports Server (NTRS)

    Nguyen, QuynhGiao, N.; Miller, Robert A.; Leissler, George W.

    2005-01-01

    Improved small-particle powders and powder-processing conditions have been developed for use in plasma spray deposition of thermal-barrier and environmental barrier coatings. Heretofore, plasma-sprayed coatings have typically ranged in thickness from 125 to 1,800 micrometers. As explained below, the improved powders make it possible to ensure complete coverage of substrates at unprecedently small thicknesses of the order of 25 micrometers. Plasma spraying involves feeding a powder into a hot, high-velocity plasma jet. The individual powder particles melt in the plasma jet as they are propelled towards a substrate, upon which they splat to build up a coating. In some cases, multiple coating layers are required. The size range of the powder particles necessarily dictates the minimum thickness of a coating layer needed to obtain uniform or complete coverage. Heretofore, powder particle sizes have typically ranged from 40 to 70 micrometers; as a result, the minimum thickness of a coating layer for complete coverage has been about 75 micrometers. In some applications, thinner coatings or thinner coating layers are desirable. In principle, one can reduce the minimum complete-coverage thickness of a layer by using smaller powder particles. However, until now, when powder particle sizes have been reduced, the powders have exhibited a tendency to cake, clogging powder feeder mechanisms and feed lines. Hence, the main problem is one of synthesizing smaller-particle powders having desirable flow properties. The problem is solved by use of a process that begins with a spray-drying subprocess to produce spherical powder particles having diameters of less than 30 micrometers. (Spherical-particle powders have the best flow properties.) The powder is then passed several times through a commercial sifter with a mesh to separate particles having diameters less than 15 micrometers. The resulting fine, flowable powder is passed through a commercial fluidized bed powder feeder into a plasma spray jet.

  17. Laboratory Powder Metallurgy Makes Tough Aluminum Sheet

    NASA Technical Reports Server (NTRS)

    Royster, D. M.; Thomas, J. R.; Singleton, O. R.

    1993-01-01

    Aluminum alloy sheet exhibits high tensile and Kahn tear strengths. Rapid solidification of aluminum alloys in powder form and subsequent consolidation and fabrication processes used to tailor parts made of these alloys to satisfy such specific aerospace design requirements as high strength and toughness.

  18. Powder-Metallurgy Process And Product

    NASA Technical Reports Server (NTRS)

    Paris, Henry G.

    1988-01-01

    Rapid-solidification processing yields alloys with improved properties. Study undertaken to extend favorable property combinations of I/M 2XXX alloys through recently developed technique of rapid-solidification processing using powder metallurgy(P/M). Rapid-solidification processing involves impingement of molten metal stream onto rapidly-spinning chill block or through gas medium using gas atomization technique.

  19. Balanced mechanical resonator for powder handling device

    NASA Technical Reports Server (NTRS)

    Sarrazin, Philippe C. (Inventor); Brunner, Will M. (Inventor)

    2012-01-01

    A system incorporating a balanced mechanical resonator and a method for vibration of a sample composed of granular material to generate motion of a powder sample inside the sample holder for obtaining improved analysis statistics, without imparting vibration to the sample holder support.

  20. Sol-Gel Synthesis Of Aluminoborosilicate Powders

    NASA Technical Reports Server (NTRS)

    Bull, Jeffrey; Leiser, Daniel; Selvaduray, Guna

    1992-01-01

    Application of sol-gel process to synthesis of aluminoborosilicate powders shows potential for control of microstructures of materials. Development of materials having enhanced processing characteristics prove advantageous in extending high-temperature endurance of fibrous refractory composite insulation made from ceramic fibers.

  1. Numerical Simulation of Aerated Powder Consolidation 1

    E-print Network

    will slowly escape by diffusing through the material. The corresponding uneven gas pressure distribution properties. Over time the excess air diffuses through the powder and eventually escapes through the top) d d p 2 FIG. 1. Geometry and coordinate systems for the vertical conical bunker. The height

  2. High-Performance Polyimide Powder Coatings

    NASA Technical Reports Server (NTRS)

    Leahy, Jonathan J.

    2014-01-01

    Researchers at NASA's Kennedy Space Center have developed advanced powder coatings for longer-lasting, improved corrosion control. The results of preliminary tests of the coatings and their resistance to salt spray corrosion are very encouraging, and commercial partners are sought for further development.

  3. Magnetic properties of dispersed magnetite powders

    Microsoft Academic Search

    L. G. Parry

    1965-01-01

    Measurements have been made of coercive force, susceptibility, isothermal remanence, thermoremanence and thermal and alternating field demagnetization of annealed magnetite powders in nine size ranges from 1·5 ? to 120 ?. The samples were dispersed in plaster to occupy a few per cent by volume of the specimens and thus to simulate the magnetic properties of rocks. The results are

  4. MODELING MERCURY CONTROL WITH POWDERED ACTIVATED CARBON

    EPA Science Inventory

    The paper presents a mathematical model of total mercury removed from the flue gas at coal-fired plants equipped with powdered activated carbon (PAC) injection for Mercury control. The developed algorithms account for mercury removal by both existing equipment and an added PAC in...

  5. Plated Metal Powders for Electrode Pastes

    NASA Technical Reports Server (NTRS)

    Bickler, D. B.

    1984-01-01

    Metal grains to be sintered precoated with frit metal. Coated metal powders used to make ink-like electrode pastes for printing and sintering electrode-fabrication process. Grains of base metal coated with lowmelting-point--, lead or tin-- by electroless deposition.

  6. Strengthening of face packing surfaces with powders

    Microsoft Academic Search

    N. N. Dorozhkin; V. N. Gimelfarb; L. P. Kashitsyn

    1983-01-01

    The Institute of Problems of Reliability and Life of Machines of the Academy of Sciences of the Belorussian SSR has developed a process of induction coalescing under the action of an activating pressure at the sintering temperature of powder under conditions of accelerated heating and realization of the so-called effect of limited space. Proposed is a method for strengthening the

  7. Screening mail for powders using terahertz technology

    NASA Astrophysics Data System (ADS)

    Kemp, Mike

    2011-11-01

    Following the 2001 Anthrax letter attacks in the USA, there has been a continuing interest in techniques that can detect or identify so-called 'white powder' concealed in envelopes. Electromagnetic waves (wavelengths 100-500 ?m) in the terahertz frequency range penetrate paper and have short enough wavelengths to provide good resolution images; some materials also have spectroscopic signatures in the terahertz region. We report on an experimental study into the use of terahertz imaging and spectroscopy for mail screening. Spectroscopic signatures of target powders were measured and, using a specially designed test rig, a number of imaging methods based on reflection, transmission and scattering were investigated. It was found that, contrary to some previous reports, bacterial spores do not appear to have any strong spectroscopic signatures which would enable them to be identified. Imaging techniques based on reflection imaging and scattering are ineffective in this application, due to the similarities in optical properties between powders of interest and paper. However, transmission imaging using time-of-flight of terahertz pulses was found to be a very simple and sensitive method of detecting small quantities (25 mg) of powder, even in quite thick envelopes. An initial feasibility study indicates that this method could be used as the basis of a practical mail screening system.

  8. Macromolecular powder diffraction : structure solution via molecular.

    SciTech Connect

    Doebbler, J.; Von Dreele, R.; X-Ray Science Division

    2009-01-01

    Macromolecular powder diffraction is a burgeoning technique for protein structure solution - ideally suited for cases where no suitable single crystals are available. Over the past seven years, pioneering work by Von Dreele et al. [1,2] and Margiolaki et al. [3,4] has demonstrated the viability of this approach for several protein structures. Among these initial powder studies, molecular replacement solutions of insulin and turkey lysozyme into alternate space groups were accomplished. Pressing the technique further, Margiolaki et al. [5] executed the first molecular replacement of an unknown protein structure: the SH3 domain of ponsin, using data from a multianalyzer diffractometer. To demonstrate that cross-species molecular replacement using image plate data is also possible, we present the solution of hen egg white lysozyme using the 60% identical human lysozyme (PDB code: 1LZ1) as the search model. Due to the high incidence of overlaps in powder patterns, especially in more complex structures, we have used extracted intensities from five data sets taken at different salt concentrations in a multi-pattern Pawley refinement. The use of image plates severely increases the overlap problem due to lower detector resolution, but radiation damage effects are minimized with shorter exposure times and the fact that the entire pattern is obtained in a single exposure. This image plate solution establishes the robustness of powder molecular replacement resulting from different data collection techniques.

  9. Thin transparent films formed from powdered glass

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Glass film less than five mils thick is formed from powdered glass dispersed in an organic liquid, deposited on a substrate, and fused into place. The thin films can be cut and shaped for contact lenses, optical filters and insulating layers.

  10. Electrohydraulic-impulse pressing of refractory powders

    Microsoft Academic Search

    K. N. Bogoyavlenskii; P. A. Kuznetsov; K. K. Mertens; V. V. Podgornyi; L. V. Kravets; V. M. Yam

    1982-01-01

    Conclusions It was experimentally established that it is possible to use electrohydraulic-impulse pressing to improve the basic physical properties of articles prepared from low-plasticity refractory powders. The advantages of making articles by combined pressing, including static pressing in a rigid mold and final electrohydraulic-impulse pressing were demonstrated.

  11. Cold spray deposition of thermoplastic powder

    Microsoft Academic Search

    Y. Xu; I. M. Hutchings

    2006-01-01

    The cold spray deposition of polyolefin powder has been investigated, at substantially lower velocities (up to ?135 m s?1) than those used in the cold gas dynamic spray (CGDS) process for metals. The particles were accelerated at room temperature in air through a cylindrical nozzle, and were deposited on to polyethylene and aluminium substrates. Fully-dense deposits were formed at temperatures substantially

  12. Problems of powder flow in tabletting processes

    Microsoft Academic Search

    J. A. Hersey

    1965-01-01

    Summary The flow of non-compacted granules in the tablet machine hopper is discussed with relevance to the unit dose of drug, which is required to be dispensed. The various factors used to describe powder flow such as angle of repose, interparticulate cohesion and friction, flow through apertures, bulk density and die fillability are considered. The effects of humidity and of

  13. Surface dose measurement using TLD powder extrapolation

    SciTech Connect

    Rapley, P. [Regional Cancer Care, Thunder Bay Regional Health Sciences Centre, Thunder Bay, Ontario (Canada)]. E-mail: rapleyp@tbh.net

    2006-10-01

    Surface/near-surface dose measurements in therapeutic x-ray beams are important in determining the dose to the dermal and epidermal skin layers during radiation treatment. Accurate determination of the surface dose is a difficult but important task for proper treatment of patients. A new method of measuring surface dose in phantom through extrapolation of readings from various thicknesses of thermoluminescent dosimeter (TLD) powder has been developed and investigated. A device was designed, built, and tested that provides TLD powder thickness variation to a minimum thickness of 0.125 mm. Variations of the technique have been evaluated to optimize precision with consideration of procedural ease. Results of this study indicate that dose measurements (relative to D{sub max}) in regions of steep dose gradient in the beam axis direction are possible with a precision (2 standard deviations [SDs]) as good as {+-} 1.2% using the technique. The dosimeter was developed and evaluated using variation to the experimental method. A clinically practical procedure was determined, resulting in measured surface dose of 20.4 {+-} 2% of the D{sub max} dose for a 10 x 10 cm{sup 2}, 80-cm source-to-surface distance (SSD), Theratron 780 Cobalt-60 ({sup 60}C) beam. Results obtained with TLD powder extrapolation compare favorably to other methods presented in the literature. The TLD powder extrapolation tool has been used clinically at the Northwestern Ontario Regional Cancer Centre (NWORCC) to measure surface dose effects under a number of conditions. Results from these measurements are reported. The method appears to be a simple and economical tool for surface dose measurement, particularly for facilities with TLD powder measurement capabilities.

  14. Metal Powder ProcessingMetal Powder Processing ME 4210: Manufacturing Processes and Engineering

    E-print Network

    Colton, Jonathan S.

    shields Valve inserts, bushings, gears Electrical/electronic Heat treating Joining Lubrication Ag, Au, Mo is called greenp p g compact. (b) Typical tool and die set for compacting a spur gear. Source: Metal Powder

  15. Consolidation of aluminum 6061 powder by equal channel angular extrusion 

    E-print Network

    Pearson, John Montgomery

    1997-01-01

    Equal channel angular extrusion is a promising approach to obtaining full density in powder metallurgy applications. This method can impose large effective deformations through uniform shear strain. Aluminum alloy 6061 powder is used as a test...

  16. Rheological and Thermal Debinding Behaviors in Titanium Powder Injection Molding

    NASA Astrophysics Data System (ADS)

    Park, Seong-Jin; Wu, Yunxin; Heaney, Donald F.; Zou, Xin; Gai, Guosheng; German, Randall M.

    2009-01-01

    Powder injection molding (PIM) is suitable for the fabrication of complex shape titanium and its alloys and has a great potential in many applications. This article deals with the injection molding of hydride-dehydride (HDH) titanium powder, spheroidized HDH titanium powder, and gas-atomized (GA) titanium powder. Rheological and thermal debinding behaviors are compared between feedstocks made from the three powders. Torque and capillary rheometers are used to investigate rheological behavior as it relates to the power-law model of viscosity and moldability index. Thermogravimetric analysis (TGA) was employed to analyze debinding behavior given a master decomposition curve consisting of two sigmoids. Spheroidized HDH Ti powder behaves in a manner similar to GA Ti powder. The analysis of the results in this study indicates the possibility of using a combination of HDH and GA titanium powders for PIM.

  17. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS § 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  18. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS § 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  19. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS § 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  20. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS § 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  1. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS § 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  2. In vitro bioactivity of a biocomposite fabricated from HA and Ti powders by powder metallurgy method

    Microsoft Academic Search

    C. Q. Ning; Y. Zhou

    2002-01-01

    Traditionally, hydroxyapatite was used as a coating material on titanium substrate by various techniques. In the present work, a biocomposite was successfully fabricated from hydroxyapatite and titanium powders by powder metallurgy method. Bioactivity of the composite in a simulated body fluid (SBF) was investigated. Main crystal phases of the as-fabricated composite are found to be Ti2O, CaTiO3, CaO, ?-Ti and

  3. Kinetics of bacterial death by heated dolomite powder slurry

    Microsoft Academic Search

    Jun Sawai; Kyoko Himizu; Osamu Yamamoto

    2005-01-01

    The kinetics of the bactericidal action of dolomite powders heated at 600–1000°C against Escherichia coli and Staphylococcus aureus were investigated. Dolomite powder heated to at least 700°C exhibited bactericidal action, and the process of bacterial death in the heated dolomite powder slurries followed first-order reaction kinetics. The value of the death rate constant (k) increased with dolomite powder concentration, and

  4. High temperature shock consolidation of hard ceramic powders

    NASA Astrophysics Data System (ADS)

    Hokamoto, K.; Tanaka, S.; Fujita, M.; Itoh, S.; Meyers, M. A.; Chen, H.-C.

    1997-02-01

    High-temperature shoch consolidation of hard ceramic powders was used as a means to improve bonding between powders and to decrease the number of cracks generated in the consolidated sample. A converging underwater shock-wave assembly was used for the compaction, and TiB 2, c-BN and their mixed powders were consolidated at various conditions up to 850°C. The positive effects by heating the powders were confirmed by the experiments conducted.

  5. Aero-sol-gel Reactor for Nano-powder Synthesis

    Microsoft Academic Search

    G. Beaucage; J. Hyeon-Lee; D. J. Kohls; S. E. Pratsinis

    1999-01-01

    This paper discusses a new approach to the synthesis of nano-structured oxides where sol-gel reactions are carried out in aerosol droplets. This aero-sol-gel (ASG) reactor allows for manipulation of the structure, chemical composition and surface area of silica powders through variation of process parameters. ASG powders differ in nanostructure from other continuous process powders such as pyrolytic and solution-route powders.

  6. Calculation of laser absorption by metal powders in additive manufacturing.

    PubMed

    Boley, C D; Khairallah, S A; Rubenchik, A M

    2015-03-20

    We have calculated the absorption of laser light by a powder of metal spheres, typical of the powder employed in laser powder-bed fusion additive manufacturing. Using ray-trace simulations, we show that the absorption is significantly larger than its value for normal incidence on a flat surface, due to multiple scattering. We investigate the dependence of absorption on powder content (material, size distribution, and geometry) and on beam size. PMID:25968537

  7. Study on starch- graft-acrylamide\\/mineral powder superabsorbent composite

    Microsoft Academic Search

    Jihuai Wu; Yueling Wei; Jianming Lin; Songbai Lin

    2003-01-01

    A novel starch-graft-acrylamide\\/mineral powder superabsorbent composite with water absorbency about 4000 times is synthesized by graft-copolymerization reaction among acrylamide, potato starch and mineral ultrafinepowder, followed by hydrolysis with sodium hydroxide. It is found that the composite doped with kaolinite powder possess higher water absorbency than those doped with bentonite or sercite powder, since the kaolinite powder can moderately disperse in

  8. Sintering characteristics of highly active UO2 powder

    SciTech Connect

    Saiki, Wataru; Onoue, Takeshi; Hasegawa, Shinichi [Mitsubishi Metal Company, Ibaraki (Japan)] [and others

    1995-12-31

    A highly active UO{sub 2} powder of 5 to 15m{sup 2}/g specific surface area can be obtained by a conversion process we have developed. This powder can be sintered to high density at a lower temperature than conventional powder; thus, the sintering temperature can be lowered in the manufacturing plant. In this study, sintering characteristics of the active powder, such as correlation of density with temperature, grain growth with sintering time, etc., have been evaluated.

  9. Study of Velocity and Materials on Tribocharging of Polymer Powders for Powder Coating Applications

    NASA Technical Reports Server (NTRS)

    Biris, Alex S.; Trigwell, Steve; Sims, Robert A.; Mazumder, Malay K.

    2005-01-01

    Electrostatic powder deposition is widely used in a plethora of industrial-applications ranging from the pharmaceutical and food.industries, to farm equipment and automotive applications. The disadvantages of this technique are possible back corona (pin-like formations) onset and the Faraday penetration limitation (when the powder does not penetrate in some recessed areas). A possible solution to overcome these problems is to use tribochargers to electrostatically charge the powder. Tribocharging, or contact charging while two materials are in contact, is related to the work function difference between the contacting materials and generates bipolarly charged particles. The generation of an ion-free powder cloud by tribocharging with high bipolar charge and an overall charge density of almost zero, provides a better coverage of the recessed areas. In this study, acrylic and epoxy powders were fluidized and charged by passing through stainless steel, copper, aluminum, and polycarbonate static mixers, respectively. The particle velocity was varied to determine its effect on the net charge-to-mass ratio (QIM) acquired by the powders. In general, the Q/M increases rapidly when the velocity was increased from 1.5 to 2.5 m/s, remaining almost constant for higher velocities. Charge separation experiments showed bipolar charging for all chargers.

  10. Substitution of Micron by Nanometer Scale Powders in Magnetorheological Fluids

    NASA Astrophysics Data System (ADS)

    Chaudhuri, A.; Wang, G.; Wereley, N. M.; Tasovksi, Vasil; Radhakrishnan, R.

    The effects of substitution of micron size powder by nanometer size powder in magnetorheological (MR) fluids are investigated in this study. Three MR fluid samples containing iron powder with 45% weight fraction in a carrier fluid were made by Materials Modification Inc. The difference among these three fluids is size of the magnetic particles. The first MR fluid sample contained only micron size iron powder with 10?m particle size. In the second sample, 5% micron iron was substituted with nano powders having 30~40nm mean diameter, while the third sample had 37.5% micron powder and 7.5% nano powder. Rheological tests were conducted on the three samples using a parallel disk rheometer. Highest yield stress was observed in the second MR fluid sample containing 40% micron and 5% nano iron powder. By replacing only 5% micron iron powder with nanoparticles, we achieved substantial increment in yield stress. However, when nano powder content is increased to 7.5%, the yield stress decreases and is lower than that in the all micron MR fluid. Thus, by doping a reasonable percent of nano iron powder in the MR fluid, a substantial change in the rheological characteristics is obtainable. Further investigations of effects of nano iron powder in MR fluids for higher weight fraction MR fluids will be carried out in future.

  11. Engineering Our work is focused on the study of Powder

    E-print Network

    powder transport and burning, electrostatic precipitation and heat transfer. At CCNY, he did researchChemical Engineering Abstract Our work is focused on the study of Powder Mechanics and the ultimate goal is to develop a quantitative description of flows for a wide variety of powders using a continuous

  12. Heating of metallic powders by microwaves: Experiment and theory

    Microsoft Academic Search

    V. D. Buchelnikov; D. V. Louzguine-Luzgin; G. Xie; S. Li; N. Yoshikawa; M. Sato; A. P. Anzulevich; I. V. Bychkov; A. Inoue

    2008-01-01

    It is known that bulk metallic samples reflect microwaves while powdered samples can absorb such radiation and be heated efficiently. In the present work we studied heating mechanisms of metallic powders in a multimode 2.45 GHz microwave applicator. The present paper shows direct evidence of penetration of a layer of metallic powder by microwave radiation and provides theoretical explanation of

  13. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2009-04-01 true Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard § 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  14. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard § 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  15. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard § 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  16. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard § 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  17. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard § 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  18. Free radical interactions between raw materials in dry soup powder.

    PubMed

    Raitio, Riikka; Orlien, Vibeke; Skibsted, Leif H

    2011-12-01

    Interactions at the free radical level were observed between dry ingredients in cauliflower soup powder, prepared by dry mixing of ingredients and rapeseed oil, which may be of importance for quality deterioration of such dry food products. The free radical concentrations of cauliflower soup powder, obtained by electron spin resonance (ESR) spectroscopy, rapidly become smaller during storage (40°C and relative humidity of 75%) than the calculated concentrations of free radicals based on the free radical concentrations of the powder ingredients used to make the soup powder and stored separately under similar conditions. Similarly, free radical concentrations decreased faster when any combination of two powder ingredients (of the three major ingredients of the soup powder) were mixed together and stored at 50°C for 1week than when each powder component was stored separately. Furthermore, yeast extract powder was found to play a key role when free radical interactions between powder ingredients occurred. The incubation of rapeseed oil with powder ingredients at 45°C for 24h, indicated the ability of cauliflower powder to increase the concentration of hydroperoxides in rapeseed oil, while yeast extract powder was found to prevent this hydroperoxide formation. PMID:25212323

  19. Spouting of fine powder from vertically vibrated bed

    Microsoft Academic Search

    S. Harada; H. Li; K. Funatsu; Y. Tomita

    2002-01-01

    Experimental and numerical studies of spouting of powder from vertically vibrated bed are performed. The powder flows out vigorously through a side orifice of the vertically vibrated vessel in which the powder is contained, provided that the vibration acceleration is greater than the gravitational one. The mechanism of the efflux and the relationship between the efflux rate and the vibration

  20. 21 CFR 169.182 - Vanilla-vanillin powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Vanilla-vanillin powder. 169.182 Section 169.182 Food...Dressings and Flavorings § 169.182 Vanilla-vanillin powder. (a) Vanilla-vanillin powder conforms to the definition and...

  1. 21 CFR 169.182 - Vanilla-vanillin powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Vanilla-vanillin powder. 169.182 Section 169.182 Food...Dressings and Flavorings § 169.182 Vanilla-vanillin powder. (a) Vanilla-vanillin powder conforms to the definition and...

  2. 21 CFR 169.182 - Vanilla-vanillin powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Vanilla-vanillin powder. 169.182 Section 169.182 Food...Dressings and Flavorings § 169.182 Vanilla-vanillin powder. (a) Vanilla-vanillin powder conforms to the definition and...

  3. 49 CFR 173.171 - Smokeless powder for small arms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Smokeless powder for small arms. 173.171 Section 173.171 Transportation Other Regulations...Class 1 and Class 7 § 173.171 Smokeless powder for small arms. Powders that have been classed in Division 1.3 or...

  4. 49 CFR 173.171 - Smokeless powder for small arms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Smokeless powder for small arms. 173.171 Section 173.171 Transportation...Class 7 § 173.171 Smokeless powder for small arms. Smokeless powder for small arms which has been classed in Division 1.3...

  5. 49 CFR 173.170 - Black powder for small arms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 false Black powder for small arms. 173.170 Section 173.170 Transportation...and Class 7 § 173.170 Black powder for small arms. Black powder for small arms that has been classed in Division 1.1 may...

  6. 49 CFR 173.170 - Black powder for small arms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 2012-10-01 false Black powder for small arms. 173.170 Section 173.170 Transportation...and Class 7 § 173.170 Black powder for small arms. Black powder for small arms that has been classed in Division 1.1 may...

  7. 49 CFR 173.170 - Black powder for small arms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 false Black powder for small arms. 173.170 Section 173.170 Transportation...and Class 7 § 173.170 Black powder for small arms. Black powder for small arms that has been classed in Division 1.1 may...

  8. 49 CFR 173.171 - Smokeless powder for small arms.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Smokeless powder for small arms. 173.171 Section 173.171 Transportation...Class 7 § 173.171 Smokeless powder for small arms. Smokeless powder for small arms which has been classed in Division 1.3...

  9. 49 CFR 173.171 - Smokeless powder for small arms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Smokeless powder for small arms. 173.171 Section 173.171 Transportation...Class 7 § 173.171 Smokeless powder for small arms. Smokeless powder for small arms which has been classed in Division 1.3...

  10. Barium strontium titanate powders prepared by spray pyrolysis

    Microsoft Academic Search

    G. Brankovi?; Z. Brankovi?; M. S. Góes; C. O. Paiva-Santos; M. Cilense; J. A. Varela; E. Longo

    2005-01-01

    Ultasonic spray pyrolysis (SP) has been investigated for the production of the barium strontium titanate (BST) powders from the polymeric precursors. The processing parameters, such as flux of aerosol and temperature profile inside the furnace, were optimized to obtain single phase BST. The powders were characterized by the methods of X-ray diffraction analysis, SEM, EDS and TEM. The obtained powders

  11. Manufacture and application of high milk protein powder1

    E-print Network

    Boyer, Edmond

    Review Manufacture and application of high milk protein powder1 Vikram V. MISTRY MN-SD Dairy Foods was developed for the production of a high milk protein powder that was rich in both milk proteins, casein with the most lactose, such as skim milk powder, had the most wrinkles. The virtual absence of lactose

  12. Dynamics and Biodiversity of Populations of Lactic Acid Bacteria and Acetic Acid Bacteria Involved in Spontaneous Heap Fermentation of Cocoa Beans in Ghana?

    PubMed Central

    Camu, Nicholas; De Winter, Tom; Verbrugghe, Kristof; Cleenwerck, Ilse; Vandamme, Peter; Takrama, Jemmy S.; Vancanneyt, Marc; De Vuyst, Luc

    2007-01-01

    The Ghanaian cocoa bean heap fermentation process was studied through a multiphasic approach, encompassing both microbiological and metabolite target analyses. A culture-dependent (plating and incubation, followed by repetitive-sequence-based PCR analyses of picked-up colonies) and culture-independent (denaturing gradient gel electrophoresis [DGGE] of 16S rRNA gene amplicons, PCR-DGGE) approach revealed a limited biodiversity and targeted population dynamics of both lactic acid bacteria (LAB) and acetic acid bacteria (AAB) during fermentation. Four main clusters were identified among the LAB isolated: Lactobacillus plantarum, Lactobacillus fermentum, Leuconostoc pseudomesenteroides, and Enterococcus casseliflavus. Other taxa encompassed, for instance, Weissella. Only four clusters were found among the AAB identified: Acetobacter pasteurianus, Acetobacter syzygii-like bacteria, and two small clusters of Acetobacter tropicalis-like bacteria. Particular strains of L. plantarum, L. fermentum, and A. pasteurianus, originating from the environment, were well adapted to the environmental conditions prevailing during Ghanaian cocoa bean heap fermentation and apparently played a significant role in the cocoa bean fermentation process. Yeasts produced ethanol from sugars, and LAB produced lactic acid, acetic acid, ethanol, and mannitol from sugars and/or citrate. Whereas L. plantarum strains were abundant in the beginning of the fermentation, L. fermentum strains converted fructose into mannitol upon prolonged fermentation. A. pasteurianus grew on ethanol, mannitol, and lactate and converted ethanol into acetic acid. A newly proposed Weissella sp., referred to as “Weissella ghanaensis,” was detected through PCR-DGGE analysis in some of the fermentations and was only occasionally picked up through culture-based isolation. Two new species of Acetobacter were found as well, namely, the species tentatively named “Acetobacter senegalensis” (A. tropicalis-like) and “Acetobacter ghanaensis” (A. syzygii-like). PMID:17277227

  13. Complete genome sequence and comparative analysis of Acetobacter pasteurianus 386B, a strain well-adapted to the cocoa bean fermentation ecosystem

    PubMed Central

    2013-01-01

    Background Acetobacter pasteurianus 386B, an acetic acid bacterium originating from a spontaneous cocoa bean heap fermentation, proved to be an ideal functional starter culture for coca bean fermentations. It is able to dominate the fermentation process, thereby resisting high acetic acid concentrations and temperatures. However, the molecular mechanisms underlying its metabolic capabilities and niche adaptations are unknown. In this study, whole-genome sequencing and comparative genome analysis was used to investigate this strain’s mechanisms to dominate the cocoa bean fermentation process. Results The genome sequence of A. pasteurianus 386B is composed of a 2.8-Mb chromosome and seven plasmids. The annotation of 2875 protein-coding sequences revealed important characteristics, including several metabolic pathways, the occurrence of strain-specific genes such as an endopolygalacturonase, and the presence of mechanisms involved in tolerance towards various stress conditions. Furthermore, the low number of transposases in the genome and the absence of complete phage genomes indicate that this strain might be more genetically stable compared with other A. pasteurianus strains, which is an important advantage for the use of this strain as a functional starter culture. Comparative genome analysis with other members of the Acetobacteraceae confirmed the functional properties of A. pasteurianus 386B, such as its thermotolerant nature and unique genetic composition. Conclusions Genome analysis of A. pasteurianus 386B provided detailed insights into the underlying mechanisms of its metabolic features, niche adaptations, and tolerance towards stress conditions. Combination of these data with previous experimental knowledge enabled an integrated, global overview of the functional characteristics of this strain. This knowledge will enable improved fermentation strategies and selection of appropriate acetic acid bacteria strains as functional starter culture for cocoa bean fermentation processes. PMID:23902333

  14. Characterization of pharmaceutical powder inhalers: estimation of energy input for powder dispersion and effect of capsule device configuration

    Microsoft Academic Search

    Nora Y. K. Chew; Hak-Kim Chan; David F. Bagster; Jay Mukhraiya

    2002-01-01

    The present study was aimed to examine (i) the overall energy input (Edispersion) into two capsule-type pharmaceutical powder inhalers, the Dinkihaler® and the Rotahaler®, and (ii) the effect due to the presence of capsule, on powder dispersion using mannitol as a model compound.Powder dispersion was assessed by a liquid impinger with the fine particle fraction (FPF) defined as the wt.%

  15. Weavability of dry polymer powder towpreg

    NASA Technical Reports Server (NTRS)

    Hugh, Maylene K.; Marchello, Joseph M.; Maiden, Janice R.; Johnston, Norman J.

    1993-01-01

    Carbon fiber yarns (3k, 6k, 12k) were impregnated with LARC (tm) thermoplastic polyimide dry powder. Parameters for weaving these yarns were established. Eight-harness satin fabrics were successfully woven from each of the three classes of yarns and consolidated into test specimens to determine mechanical properties. It was observed that for optimum results warp yarns should have flexural rigidities between 10,000 and 100,000 mg-cm. Tow handling minimization, low tensioning, and tow bundle twisting were used to reduce fiber breakage, the separation of filaments, and tow-to-tow abrasion. No apparent effect of tow size or twist was observed on either tension or compression modulus. However, fiber damage and processing costs favor the use of 12k yarn bundles versus 3k or 6k yarn bundles in the weaving of powder-coated towpreg.

  16. Complex hydrides - when powder diffraction needs help.

    PubMed

    Schouwink, Pascal; Cerný, Radovan

    2014-01-01

    'Real life' energy-related materials such as solid-state hydrogen storage compounds or components of electrochemical cells are usually polycrystalline, poorly crystallized, highly reactive and dynamic systems. Powder diffraction at modern high brilliance X-ray sources is the most useful tool to investigate such systems because it is easy, fast and extremely versatile with respect to measurement conditions as well as in situ setups. However, it is in the nature of these systems that they undergo processes that cannot be investigated by diffraction alone. The central role in hydrogen storage materials is played by hydrogen itself, the worst X-ray scatterer in the periodic system. Gas release, the purpose of a hydrogen storage material, is not detected by diffraction. Amorphous components are badly characterized. We want to show how a complementary approach combining different methods allows to overcome limitations imposed on powder diffraction by the sample nature of 'real' hydrogen storage materials. PMID:24801695

  17. Fabricating solid carbon porous electrodes from powders

    DOEpatents

    Kaschmitter, J.L.; Tran, T.D.; Feikert, J.H.; Mayer, S.T.

    1997-06-10

    Fabrication is described for conductive solid porous carbon electrodes for use in batteries, double layer capacitors, fuel cells, capacitive deionization, and waste treatment. Electrodes fabricated from low surface area (<50 m{sup 2}/gm) graphite and cokes exhibit excellent reversible lithium intercalation characteristics, making them ideal for use as anodes in high voltage lithium insertion (lithium-ion) batteries. Electrodes having a higher surface area, fabricated from powdered carbon blacks, such as carbon aerogel powder, carbon aerogel microspheres, activated carbons, etc. yield high conductivity carbon composites with excellent double layer capacity, and can be used in double layer capacitors, or for capacitive deionization and/or waste treatment of liquid streams. By adding metallic catalysts to high surface area carbons, fuel cell electrodes can be produced. 1 fig.

  18. Colloidal characterization of ultrafine silicon carbide and silicon nitride powders

    NASA Technical Reports Server (NTRS)

    Whitman, Pamela K.; Feke, Donald L.

    1986-01-01

    The effects of various powder treatment strategies on the colloid chemistry of aqueous dispersions of silicon carbide and silicon nitride are examined using a surface titration methodology. Pretreatments are used to differentiate between the true surface chemistry of the powders and artifacts resulting from exposure history. Silicon nitride powders require more extensive pretreatment to reveal consistent surface chemistry than do silicon carbide powders. As measured by titration, the degree of proton adsorption from the suspending fluid by pretreated silicon nitride and silicon carbide powders can both be made similar to that of silica.

  19. Low-Flow-Rate Dry-Powder Feeder

    NASA Technical Reports Server (NTRS)

    Ramsey, Keith E.

    1994-01-01

    Apparatus feeds small, precise flow of dry powder through laser beam of optical analyzer, measuring patterns of light created by forward scattering (Fraunhofer diffraction) of laser beam from powder particles. From measurement, statistical distribution of sizes of powder particles computed. Developed for analyzing particle-size distributions of solid-propellant powders. Also adapted to use in pharmaceutical industry, in manufacture of metal powder, and in other applications in which particle-size distributions of materials used to control rates of chemical reactions and/or physical characteristics of processes.

  20. Low-Flow-Rate Dry-Powder Feeder

    NASA Technical Reports Server (NTRS)

    Ramsey, Keith E.

    1994-01-01

    Apparatus feeds small, precise flow of dry powder through laser beam of optical analyzer measuring patterns of light created by forward scattering (Fraunhofer diffraction) of laser beam from powder particles. From this optical measurement, statistical distribution of sizes of powder particles computed. Rates of flow optimized for measurement of particle-size distributions. Developed for analyzing particle-size distributions of solid-propellant powders. Also adapted to pharmaceutical industry, in manufacture of metal powder, and in other applications where particle-size distributions of materials used to control rates of chemical reactions and/or physical characteristics of processes.

  1. The reflection of very cold neutrons from diamond powder nanoparticles

    E-print Network

    V. V. Nesvizhevsky; E. V. Lychagin; A. Yu. Muzychka; A. V. Strelkov; G. Pignol; K. V. Protasov

    2008-05-17

    We study possibility of efficient reflection of very cold neutrons (VCN) from powders of nanoparticles. In particular, we measured the scattering of VCN at a powder of diamond nanoparticles as a function of powder sample thickness, neutron velocity and scattering angle. We observed extremely intense scattering of VCN even off thin powder samples. This agrees qualitatively with the model of independent nanoparticles at rest. We show that this intense scattering would allow us to use nanoparticle powders very efficiently as the very first reflectors for neutrons with energies within a complete VCN range up to $10^{-4}$ eV.

  2. The analysis of powder diffraction data

    Microsoft Academic Search

    M. J. Cooper

    1982-01-01

    A comparison has been carried out between the results of analyses of several sets of neutron powder diffraction data using three different methods: the Rietveld method (H. M. Rietveld, Acta. Cryst. 22, 151–152 (1967): J. Appl. Cryst. 2, 65–71 (1969), a modification of the Rietveld method to include off-diagonal terms in the weight matrix (C. P. Clarke and J. S.

  3. The analysis of powder diffraction data

    Microsoft Academic Search

    M. J. Cooper

    1982-01-01

    A comparison has been carried out between the results of analyses of several sets of neutron powder diffraction data using three different methods: the Rietveld method (H. M. Rietveld, Acta. Cryst. 22, 151-152 (1967): J. Appl. Cryst. 2, 65-71 (1969), a modification of the Rietveld method to include off-diagonal terms in the weight matrix (C. P. Clarke and J. S.

  4. Strengthening of face packing surfaces with powders

    Microsoft Academic Search

    N. N. Dorozhkin; V. N. Gimelfarb; L. P. Kashitsyn

    1983-01-01

    The primary reason for failure of centrifugal pumps used in chemical fiber production plants is failure of the tightness of the rubbing surfaces of the face packing surfaces caused by mechanical-corrosion wear. To increase the life, coatings of Ni-Cr-B-Si selffluxing alloy powders are normally applied to their working surface. A process has been developed for induction coalescing under the action

  5. Substantiating powder metal life methodologies for engines

    Microsoft Academic Search

    P. A. Domas

    1993-01-01

    The application of powder metal (PM) superalloys in aircraft turbine engine rotating components is prompted by performance driven high strength and creep resistance requirements. Fine grain, precipitation strengthened nickel-base alloys such as IN100, Rene'95, and Rene'88DT meet these requirements up to operating temperatures in the 1200-1300F (649-704C) range. In addition to burst and deformation limits, design constraints include durability (fatigue)

  6. Photolytic decomposition of lithium aluminum hydride powder

    Microsoft Academic Search

    P. J. Herley; D. H. Spencer

    1979-01-01

    The ultraviolet photolysis of powdered LiAlHâ has been investigated at room temperature by using pristine material and material subjected to ⁶°Co ..gamma..-ray irradiation. In all sampls, similar shaped pressure vs. time curves are obtained that comprise an initial deceleratory period followed by a constant rate of hydrogen gas evolution. The data curves can be resolved into one saturating-exponential component and

  7. Welding of a powder metallurgy uranium alloy

    Microsoft Academic Search

    R. K. Holbert; M. W. Doughty; G. M. Alexander-Morrison

    1989-01-01

    The interest at the Oak Ridge Y-12 Plant in powder metallurgy (P\\/M) uranium parts is due to the potential cost savings in the fabrication of the material, to achieving a more homogeneous product, and to the reduction of uranium scrap. The joining of P\\/M uranium-6 wt-% niobium (U-6Nb) alloys by the electron beam (EB) welding process results in weld porosity.

  8. Powder specific active dispersion for generation of pharmaceutical aerosols.

    PubMed

    Crowder, T; Hickey, A

    2006-12-11

    Dry powder inhalers are increasingly employed to deliver pharmaceutical aerosols. Efficient mechanisms of particle dispersion are central to their success in disease therapy. Creation of a powder aerosol requires the input of energy to transition the static powder bed into an entrained aerosol. The purpose of this study was to investigate the effects of input of vibrational energy into a powder on aerosol entrainment. Rotating drum characterization of powder flow was performed on lactose and maltodextrin excipients blended with albuterol sulfate. Dispersion experiments were conducted using an entrainment tube and a vibration actuator, vibrational energy input being derived from analysis of powder flow data from rotating drum analysis. Results of analysis of the rotating drum data showed that with increasing rotational speed powders reached a constant state of fluidization with a mean avalanche time dependent on the powder. Dispersion experiments demonstrated that the input of vibrational energy increased the dose emission while the input of frequencies specific to the powders improved the reproducibility. Frequency analysis of the vibration signals indicated that the reproducibility was determined by the bandwidth of the signal. This work suggests that an ability to tailor energy input to match the flow properties of a given powder formulation may significantly improve reproducibility of dose delivery from active dry powder inhalers. PMID:16930884

  9. Whey Protein/Polysaccharide-Stabilized Oil Powders for Topical Application-Release and Transdermal Delivery of Salicylic Acid from Oil Powders Compared to Redispersed Powders.

    PubMed

    Kotzé, Magdalena; Otto, Anja; Jordaan, Anine; du Plessis, Jeanetta

    2015-08-01

    Oil-in-water (o/w) emulsions are commonly converted into solid-like powders in order to improve their physical and chemical stabilities. The aim of this study was to investigate whether whey protein/polysaccharide-stabilized o/w emulsions could be converted into stable oil powders by means of freeze-drying. Moreover, during this study, the effects of pH and polymer type on release and trans(dermal) delivery of salicylic acid, a model drug, from these oil powders were investigated and compared to those of the respective template emulsions and redispersed oil powders. Physical characterization of the various formulations was performed, such as droplet size analysis and oil leakage, and relationships drawn with regards to release and trans(dermal) delivery. The experimental outcomes revealed that the oil powders could be redispersed in water without changing the release characteristics of salicylic acid. pH and polymer type affected the release of salicylic acid from the oil powders, template emulsions, and redispersed powders similarly. Contrary, the transdermal delivery from the oil powders and from their respective redispersed oil powders was differently affected by pH and polymer type. It was hypothesized that the release had been influenced by the electrostatic interactions between salicylic acid and emulsifiers, whereas the transdermal performance could have been determined by the particle or aggregate sizes of the formulations. PMID:25573437

  10. Silicon nitride/silicon carbide composite densified materials prepared using composite powders

    DOEpatents

    Dunmead, S.D.; Weimer, A.W.; Carroll, D.F.; Eisman, G.A.; Cochran, G.A.; Susnitzky, D.W.; Beaman, D.R.; Nilsen, K.J.

    1997-07-01

    Prepare silicon nitride-silicon carbide composite powders by carbothermal reduction of crystalline silica powder, carbon powder and, optionally, crystalline silicon nitride powder. The crystalline silicon carbide portion of the composite powders has a mean number diameter less than about 700 nanometers and contains nitrogen. The composite powders may be used to prepare sintered ceramic bodies and self-reinforced silicon nitride ceramic bodies.

  11. Capabilities and limitations of using powder rheology and permeability to predict dry powder inhaler performance.

    PubMed

    Cordts, Eike; Steckel, Hartwig

    2012-10-01

    Dry powder inhalers play a major role in today's treatment of various respiratory diseases. A lot of effort has been put into the optimization of a device and the appropriate formulation regarding its local lung deposition. However, the complexity and interactions of different factors governing powder dispersion and, therefore, its inhalable fraction challenge research groups around the world. In the current work, binary lactose blends and adhesive ternary powder mixtures containing additional budesonide fines were produced and analyzed with dispersion measurements on the one hand and permeability and aeration measurements conducted with a powder rheometer on the other hand. By comparing the results of the bulk property and dispersion tests, it was expected to gain a better understanding about the effect of excipient fines addition to an adhesive powder mixture. It could be observed that with permeability testing it was possible to clearly differentiate between different amounts of fines within mixtures. However, no correlation between permeability or aeration test values and drug fine particle fraction could be determined for the observed range. Nevertheless, the use of different characterization techniques led to a clearer understanding about the influence of fines addition to an adhesive mixture. It could be demonstrated that after the surface of carrier crystals had been fully saturated, drug particles got incorporated in more stable fines' agglomerates, which resulted in a decrease in fine particle fraction upon dispersion. PMID:22902789

  12. Green tea, cocoa, and red wine polyphenols moderately modulate intestinal inflammation and do not increase high-density lipoprotein (HDL) production.

    PubMed

    Nicod, Nathalie; Chiva-Blanch, Gemma; Giordano, Elena; Dávalos, Alberto; Parker, Robert S; Visioli, Francesco

    2014-03-12

    Although polyphenols are often merely perceived as antioxidants, their biological activities are manifold and include anti-inflammatory actions. A new area of research on polyphenols and health concerns their putative role in cholesterol metabolism, in particular, their high-density lipoprotein-cholesterol (HDL-c)-raising potential. Indeed, some human studies showed that administration of polyphenol-rich foods such as cocoa, green tea, and extra virgin olive oil modulate and increase HDL-c concentrations. This study assessed the effects of polyphenols on intestinal inflammation, using the physiologically relevant Caco-2 Transwell model and using lipopolysaccharide (LPS) to trigger inflammation. This study also investigated the mechanisms of actions behind the proposed HDL-c-increasing effects of polyphenols. The data suggest that polyphenols (at least those from red wine, cocoa, and green tea) administered at a dietary dose moderately modulate intestinal inflammation but do not increase cholesterol secretion by intestinal cells or enhance HDL functionality. Nutraceuticals and supplements provide pharmanutritional doses that might, conversely, produce beneficial effects. PMID:24559192

  13. Dry powder process for preparing uni-tape prepreg from polymer powder coated filamentary towpregs

    NASA Technical Reports Server (NTRS)

    Wilkinson, Steven P. (Inventor); Johnston, Norman J. (Inventor); Marchello, Joseph M. (Inventor)

    1997-01-01

    A process for preparing uni-tape prepreg from polymer powder coated filamentary towpregs is provided. A plurality of polymer powder coated filamentary towpregs are provided. The towpregs are collimated so that each towpreg is parallel. A material is applied to each side of the towpreg to form a sandwich. The sandwich is heated to a temperature wherein the polymer flows and intimately contacts the filaments and pressure is repeatedly applied perpendicularly to the sandwich with a longitudinal oscillating action wherein the filaments move apart and the polymer wets the filaments forming a uni-tape prepreg. The uni-tape prepreg is subsequently cooled.

  14. Large Bore Powder Gun Qualification (U)

    SciTech Connect

    Rabern, Donald A. [Los Alamos National Laboratory; Valdiviez, Robert [Los Alamos National Laboratory

    2012-04-02

    A Large Bore Powder Gun (LBPG) is being designed to enable experimentalists to characterize material behavior outside the capabilities of the NNSS JASPER and LANL TA-55 PF-4 guns. The combination of these three guns will create a capability to conduct impact experiments over a wide range of pressures and shock profiles. The Large Bore Powder Gun will be fielded at the Nevada National Security Site (NNSS) U1a Complex. The Complex is nearly 1000 ft below ground with dedicated drifts for testing, instrumentation, and post-shot entombment. To ensure the reliability, safety, and performance of the LBPG, a qualification plan has been established and documented here. Requirements for the LBPG have been established and documented in WE-14-TR-0065 U A, Large Bore Powder Gun Customer Requirements. The document includes the requirements for the physics experiments, the gun and confinement systems, and operations at NNSS. A detailed description of the requirements is established in that document and is referred to and quoted throughout this document. Two Gun and Confinement Systems will be fielded. The Prototype Gun will be used primarily to characterize the gun and confinement performance and be the primary platform for qualification actions. This gun will also be used to investigate and qualify target and diagnostic modifications through the life of the program (U1a.104 Drift). An identical gun, the Physics Gun, will be fielded for confirmatory and Pu experiments (U1a.102D Drift). Both guns will be qualified for operation. The Gun and Confinement System design will be qualified through analysis, inspection, and testing using the Prototype Gun for the majority of process. The Physics Gun will be qualified through inspection and a limited number of qualification tests to ensure performance and behavior equivalent to the Prototype gun. Figure 1.1 shows the partial configuration of U1a and the locations of the Prototype and Physics Gun/Confinement Systems.

  15. Low-Cobalt Powder-Metallurgy Superalloy

    NASA Technical Reports Server (NTRS)

    Harf, F. H.

    1986-01-01

    Highly-stressed jet-engine parts made with less cobalt. Udimet 700* (or equivalent) is common nickel-based superalloy used in hot sections of jet engines for many years. This alloy, while normally used in wrought condition, also gas-atomized into prealloyed powder-metallurgy (PM) product. Product can be consolidated by hot isostatically pressing (HIPPM condition) and formed into parts such as turbine disk. Such jet-engine disks "see" both high stresses and temperatures to 1,400 degrees F (760 degrees C).

  16. Stuck in traffic: Patterns of powder adhesion.

    PubMed

    Nirmal Thyagu, N; Vasilenko, A; Voyiadjis, A; Glasser, B J; Shinbrot, T

    2012-10-01

    The adhesion of fine particles to surfaces is important for applications ranging from drug delivery to fouling of solar cells. In this letter, we show that powder adhesion can occur in unexpected patterns, concentrating particular grain types in some locations and clearing them from others, and we propose a straightforward traffic model that appears to reproduce many of the behaviors seen. The model predicts different patterns depending on inter-particle cohesion, and we find in both experiment and model that adhesion occurs in three distinct stages. PMID:23085956

  17. Laser production of articles from powders

    DOEpatents

    Lewis, Gary K. (Los Alamos, NM); Milewski, John O. (Santa Fe, NM); Cremers, David A. (Los Alamos, NM); Nemec, Ronald B. (White Rock, NM); Barbe, Michael R. (White Rock, NM)

    1998-01-01

    Method and apparatus for forming articles from materials in particulate form in which the materials are melted by a laser beam and deposited at points along a tool path to form an article of the desired shape and dimensions. Preferably the tool path and other parameters of the deposition process are established using computer-aided design and manufacturing techniques. A controller comprised of a digital computer directs movement of a deposition zone along the tool path and provides control signals to adjust apparatus functions, such as the speed at which a deposition head which delivers the laser beam and powder to the deposition zone moves along the tool path.

  18. Some characteristics of powder silica counters

    NASA Technical Reports Server (NTRS)

    Badhwar, G. D.; Pinsky, L. S.

    1980-01-01

    Following the original idea of Peters, techniques have been developed to fabricate large area powder silica counters with refractive index between 1.06 to 1.12 in thicknesses of 1 cm and 2 cm respectively. The maximum size counter is 25 cm x 25 cm but the technique can be easily extended to 40 cm x 30 cm counters. Techniques have also been developed to dope this counter with the wavelength shifter p-terphenyl uniformly. The results of test runs at the Brookhaven National Laboratory and of laboratory runs using a superconducting magnet spectrometer on their performance are reported.

  19. Laser production of articles from powders

    DOEpatents

    Lewis, G.K.; Milewski, J.O.; Cremers, D.A.; Nemec, R.B.; Barbe, M.R.

    1998-11-17

    Method and apparatus for forming articles from materials in particulate form in which the materials are melted by a laser beam and deposited at points along a tool path to form an article of the desired shape and dimensions. Preferably the tool path and other parameters of the deposition process are established using computer-aided design and manufacturing techniques. A controller comprised of a digital computer directs movement of a deposition zone along the tool path and provides control signals to adjust apparatus functions, such as the speed at which a deposition head which delivers the laser beam and powder to the deposition zone moves along the tool path. 20 figs.

  20. Physical properties of yoghurt powder produced by spray drying.

    PubMed

    Koç, Banu; Sakin-Y?lmazer, Melike; Kaymak-Ertekin, Figen; Balk?r, P?nar

    2014-07-01

    The study is an extension of an optimization study, which was planned to determine the optimum spray drying conditions (the feed, outlet and inlet air temperatures) for producing yoghurt powder. The resulting yoghurt powder at each condition was subjected to the measurement of physical properties, moisture content, and reconstitution properties. All the reconstitution properties of yoghurt powders produced under 20 different spray drying conditions according to CCRD experimental design were affected by the drying outlet temperature only. Furthermore, the bulk (bulk and tapped densities, porosity, flowability, hygroscopicity and degree of caking) and particle properties (particle size distribution, particle density and morphology) of yoghurt powder obtained from optimum spray drying conditions were also determined. The bulk, tapped and particle densities of yoghurt powder were 538, 746 and 1177 kg/m(3), respectively. The mean diameter (D4.3) and the span value of yoghurt powder were 3.053 and 2.487 ?m, respectively. PMID:24966433

  1. Amorphous powders of Al-Hf prepared by mechanical alloying

    SciTech Connect

    Schwarz, R.B.; Hannigan, J.W.; Sheinberg, H.; Tiainen, T.

    1988-01-01

    We synthesized amorphous Al/sub 50/Hf/sub 50/ alloy powder by mechanically alloying an equimolar mixture of crystalline powders of Al and Hf using hexane as a dispersant. We characterized the powder as a function of mechanical-alloying time by scanning electron microscopy, x-ray diffraction, and differential scanning calorimetry. Amorphous Al/sub 50/Hf/sub 50/ powder heated at 10 K s/sup /minus/1/ crystallizes polymorphously at 1003 K into orthorhombic AlHf (CrB-type structure). During mechanical alloying, some hexane decomposes and hydrogen and carbon are incorporated into the amorphous alloy powder. The hydrogen can be removed by annealing the powder by hot pressing at a temperature approximately 30 K below the crystallization temperature. The amorphous compacts have a diamond pyramidal hardness of 1025 DPH. 24 refs., 7 figs., 1 tab.

  2. The preference of protein powders among adult male and females: A protein powder taste study

    Microsoft Academic Search

    Joshua Manter

    2010-01-01

    Protein is essential in one's diet because it is an important component in many organs and tissues throughout the body. Athletes ingest protein in order to stimulate protein synthesis and increase lean muscle mass. In order to assist with obtaining adequate amounts of protein, athletes and bodybuilders purchase supplemental protein in the form of protein powders. Protein metabolism and digestion

  3. Synthesis of Nanocrystalline ?-Al2O3 Powder Using Acetylacetone

    Microsoft Academic Search

    J. Chandradass; Ki Hyeon Kim

    2009-01-01

    Nanocrystalline ?-Al2O3 powders have been prepared by pyrolysis of a complex compound of aluminum with acetylacetone. The volumetric ratio (alumina to acetylacetone) of the starting feedstock has been shown to be a critical factor for the formation of nano ?-Al2O3 powders. The optimum calcinations temperature of the precursor powder for crystallization of nano ?-Al2O3 was found to be 1000°C for

  4. Need for a comparative performance standard for dry powder inhalers.

    PubMed Central

    Richards, R.; Saunders, M.

    1993-01-01

    The efficacy of dry powder inhalers is dependent on the inspiratory flow rate at which they are used. The resistance to airflow through five different dry powder inhaler devices was measured. The devices were shown to vary significantly, with the Turbohaler having the highest resistance. We suggest that the performance of dry powder inhalers should be assessed at comparable pressure drops producing clinically relevant inspiratory flow rates for each device. Images PMID:8296270

  5. Mach stem characterization in Mbar designs using RSR powder

    SciTech Connect

    Staudhammer, K.P.; Johnson, K.A.

    1985-01-01

    Suitable selection of powders can be used as a modeling device for complicated experimental designs. The powder melt zone is clearly defined and the RSR-834 powder is reasonably well behaved. This experiment was with only one composition, size and distribution. However, it is believed that other morphologies, composition, and size distributions could result in a more complete modeling of the compaction process that would enable heuristic calculations of the combined effects of adiabatic temperature rise and entropic heating (strain/deformation).

  6. Effects of pressure on thermal transport in plutonium oxide powder

    Microsoft Academic Search

    P. Bielenberg; F. C. Prenger; D. K. Veirs; J. Jones

    2004-01-01

    Radial temperature profiles in plutonium oxide (PuO) powder were measured in a cylindrical vessel over a pressure range of 0.055 to 334.4 kPa with two different fill gases, helium and argon. The fine PuO powder provides a very uniform self-heating medium amenable to relatively simple mathematical descriptions. At low pressures (<0.1 kPa), the effective thermal conductivity of the powder bed

  7. Modeling density contributions in preceramic polymer\\/ceramic powder systems

    Microsoft Academic Search

    K. B. Schwartz; D. J. Rowcliffe

    1986-01-01

    A model is presented that examines the mixing of ceramic powders with preceramic polymer binders that are converted to ceramic material on pyrolysis. Such polymer\\/powder systems, which have applications in the compaction of both SiC and Si3N4 powders, can be effective in increasing the green density of die-pressed bodies. This model examines the relative importance of various physical parameters of

  8. Size of snow particles in a powder-snow avalanche

    Microsoft Academic Search

    M. Rastello; F. Rastello; H. Bellot; F. Ousset; F. Dufour

    2009-01-01

    The size of the snow particles involved in a powder-snow ava- lanche is a key parameter of the local dynamic of the flow. An experimental device has been realized to collect snow particles within powder-snow avalanches. Snow particles have been cap- tured in the powder-snow part of an avalanche triggered artifi- cially on the experimental test site of the vallee

  9. Ignitability of aluminous coating powders due to electrostatic spark

    Microsoft Academic Search

    Kwangseok Choi; Nobuyasu Sakurai; Kenzo Yanagida; Haruki Itoh

    2010-01-01

    Electrostatic Powder coating which is a surface finishing technique has widely been used in paint industry since its invention in the 1960s. However, so far, insufficient attention has been paid to the powder fires and\\/or explosion hazards caused by electrostatic spark during coating process. This paper is a report of the electrostatic spark ignitability of aluminous coating powders (dry blend-type)

  10. Stratigraphic correlation with X-ray powder patterns

    E-print Network

    Singletary, John B

    1951-01-01

    . Introduction II. Theory anc Technique of Analysis by the Powder Nethod A. :. -Ray Diffraction B. The Recording Geiger Counter Spectrometer . 8 C. Construction and Usc of Soller Collimators. 15 D. Sample Preparation and Procedure for Obtaining Powder... Pattern=. II J. Interpretation of' Results. A. Pr eparation of Logs B. Discuss'on of Logs 23 25 25 33 IV. Conclusions. 36 V. Acknowledgements VI. Bibliography 37 38 STRATIGRAPHIC CORRELATION WITH X-RAY POWDER PATTERNS I. INTROIKCTION...

  11. Mechanical properties of articles formed from powder alloy steels

    Microsoft Academic Search

    T. A. Pumpyanskaya; N. V. Krokhina; E. M. Fainshmidt

    1989-01-01

    1.The plasticity and impact strength of articles formed from powder Ni-Mo-Cu steel using nickel and molybdenum oxides are two times higher than those attained when this same steel is alloyed with metallic powders of nickel and molybdenum.2.The improved mechanical properties of steels formed from partially alloyed iron powder using nickel and molybdenum oxides are explained by the uniformity of the

  12. Injection molding of TiAl alloyed powder

    Microsoft Academic Search

    Kiyotaka Kato; Yoshihiko Nozaki

    1991-01-01

    To realize manufacturing process of near net shape, titanium aluminide powder injection molding was applied to TiAl alloyed powder. TiAl alloyed powder was mixed with the binder consisting of wax and acrylic resin at the content of 45 vol pct. Flow characteristics of this compound was evaluated by extrusion-type flow meter. Then it was injection-molded to the shape of a

  13. Powder River coalbed methane output growing fast

    SciTech Connect

    Petzet, G.A.

    1997-03-10

    Operators expect to complete several hundred wells to Cretaceous Fort Union coals this year in the northeastern Powder River basin. Favorable price and purchaser conditions and workable environmental restrictions have spawned a low cost play that has produced nearly 500 intents to drill since mid-1995. Western Gas Resources Inc., Denver, said the Powder River basin coals were delivering about 28 MMcfd of methane at yearend 1996. Another 35 MMcfd is shut-in waiting on connection and pipeline hookup. The coal is in a 40--90 ft seam 150--600 ft deep. All drilling to date has been within 10--12 miles of and downdip from about 18 large open pits from which sub-bituminous Fort Union coals have been mined. None of the coal companies captures or owns any gas. The dominant operators in the play are Western Gas Resources Inc. and Redstone Resources Inc., both of Denver, who have leased about 80% of the known play area in Wyoming. A half dozen others have smaller positions. The paper discusses Western`s plans, low well costs, understanding coals, tending the wells, and scope of the play.

  14. NanoComposite Stainless Steel Powder Technologies

    SciTech Connect

    DeHoff, R.; Glasgow, C. (MesoCoat, Inc.)

    2012-07-25

    Oak Ridge National Laboratory has been investigating a new class of Fe-based amorphous material stemming from a DARPA, Defense Advanced Research Projects Agency initiative in structural amorphous metals. Further engineering of the original SAM materials such as chemistry modifications and manufacturing processes, has led to the development of a class of Fe based amorphous materials that upon processing, devitrify into a nearly homogeneous distribution of nano sized complex metal carbides and borides. The powder material is produced through the gas atomization process and subsequently utilized by several methods; laser fusing as a coating to existing components or bulk consolidated into new components through various powder metallurgy techniques (vacuum hot pressing, Dynaforge, and hot isostatic pressing). The unique fine scale distribution of microstructural features yields a material with high hardness and wear resistance compared to material produced through conventional processing techniques such as casting while maintaining adequate fracture toughness. Several compositions have been examined including those specifically designed for high hardness and wear resistance and a composition specifically tailored to devitrify into an austenitic matrix (similar to a stainless steel) which poses improved corrosion behavior.

  15. A major advance in powder metallurgy

    NASA Technical Reports Server (NTRS)

    Williams, Brian E.; Stiglich, Jacob J., Jr.; Kaplan, Richard B.; Tuffias, Robert H.

    1991-01-01

    Ultramet has developed a process which promises to significantly increase the mechanical properties of powder metallurgy (PM) parts. Current PM technology uses mixed powders of various constituents prior to compaction. The homogeneity and flaw distribution in PM parts depends on the uniformity of mixing and the maintenance of uniformity during compaction. Conventional PM fabrication processes typically result in non-uniform distribution of the matrix, flaw generation due to particle-particle contact when one of the constituents is a brittle material, and grain growth caused by high temperature, long duration compaction processes. Additionally, a significant amount of matrix material is usually necessary to fill voids and create 100 percent dense parts. In Ultramet's process, each individual particle is coated with the matrix material, and compaction is performed by solid state processing. In this program, Ultramet coated 12-micron tungsten particles with approximately 5 wt percent nickel/iron. After compaction, flexure strengths were measured 50 percent higher than those achieved in conventional liquid phase sintered parts (10 wt percent Ni/Fe). Further results and other material combinations are discussed.

  16. Structural changes during milling of aluminum oxide powders

    NASA Technical Reports Server (NTRS)

    Ziepler, G.

    1984-01-01

    The mechanical activation of four fused corundum powders and a calcined Al2O3 powder was studied. The milled powders were characterized by their structural properties, crystallite size, and lattice distortions. Structural changes during milling, detected by X-ray line broadening analysis, gave information about the enhanced activity of the powders caused by the lattice distortions and by the decreasing crystallite size during milling. The structural changes during milling, under the same milling conditions, can be quite different for the same ceramic material, but with different characteristics in the as received state.

  17. Process for synthesizing compounds from elemental powders and product

    DOEpatents

    Rabin, Barry H. (Idaho Falls, ID); Wright, Richard N. (Idaho Falls, ID)

    1993-01-01

    A process for synthesizing intermetallic compounds from elemental powders. The elemental powders are initially combined in a ratio which approximates the stoichiometric composition of the intermetallic compound. The mixed powders are then formed into a compact which is heat treated at a controlled rate of heating such that an exothermic reaction between the elements is initiated. The heat treatment may be performed under controlled conditions ranging from a vacuum (pressureless sintering) to compression (hot pressing) to produce a desired densification of the intermetallic compound. In a preferred form of the invention, elemental powders of Fe and Al are combined to form aluminide compounds of Fe.sub.3 Al and FeAl.

  18. Controlled powder morphology experiments in megabar 304 stainless steel compaction

    SciTech Connect

    Staudhammer, K.P.; Johnson, K.A.

    1985-01-01

    Experiments with controlled morphology including shape, size, and size distribution were made on 304L stainless steel powders. These experiments involved not only the powder variables but pressure variables of 0.08 to 1.0 Mbar. Also included are measured container strain on the material ranging from 1.5% to 26%. Using a new strain controllable design it was possible to seperate and control, independently, strain and pressure. Results indicate that powder morphology, size distribution, packing density are among the pertinent parameters in predicting compaction of these powders.

  19. Nanocrystalline Rare Earth-doped Gallium Nitride Phosphor Powders

    Microsoft Academic Search

    G. A. Hirata; J. Tao; P. Chen; K. C. Mishra; J. McKittrick

    We report on the fabrication and luminescent properties of rare earth-doped gallium nitride (GaN) phosphor powders. Single phase GaN and GaN:RE3+ powders were prepared by using a novel chemical route. In this work a new method for the synthesis of high purity, single phase doped GaN powders is reported. (Ga1-xREx)N powders are obtained by dissolving metal nitrates (Ga(NO3)3, (RE(NO3)3) in

  20. 21 CFR 866.1640 - Antimicrobial susceptibility test powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Diagnostic Devices § 866.1640 Antimicrobial susceptibility test powder. (a)...

  1. Reducing metal alloy powder costs for use in powder bed fusion additive manufacturing: Improving the economics for production

    NASA Astrophysics Data System (ADS)

    Medina, Fransisco

    Titanium and its associated alloys have been used in industry for over 50 years and have become more popular in the recent decades. Titanium has been most successful in areas where the high strength to weight ratio provides an advantage over aluminum and steels. Other advantages of titanium include biocompatibility and corrosion resistance. Electron Beam Melting (EBM) is an additive manufacturing (AM) technology that has been successfully applied in the manufacturing of titanium components for the aerospace and medical industry with equivalent or better mechanical properties as parts fabricated via more traditional casting and machining methods. As the demand for titanium powder continues to increase, the price also increases. Titanium spheroidized powder from different vendors has a price range from 260/kg-450/kg, other spheroidized alloys such as Niobium can cost as high as $1,200/kg. Alternative titanium powders produced from methods such as the Titanium Hydride-Dehydride (HDH) process and the Armstrong Commercially Pure Titanium (CPTi) process can be fabricated at a fraction of the cost of powders fabricated via gas atomization. The alternative powders can be spheroidized and blended. Current sectors in additive manufacturing such as the medical industry are concerned that there will not be enough spherical powder for production and are seeking other powder options. It is believed the EBM technology can use a blend of spherical and angular powder to build fully dense parts with equal mechanical properties to those produced using traditional powders. Some of the challenges with angular and irregular powders are overcoming the poor flow characteristics and the attainment of the same or better packing densities as spherical powders. The goal of this research is to demonstrate the feasibility of utilizing alternative and lower cost powders in the EBM process. As a result, reducing the cost of the raw material to reduce the overall cost of the product produced with AM. Alternative powders can be made by blending or re-spheroidizing HDH and CPTi powders. Machine modifications were performed to allow the testing and manufacturing with these low cost alternative powders. A comparison was made between alternative powders and gas atomized powders. Powders were compared in terms of morphology and at the microstructural level. Flowability of different powder blends was also measured. Finally, a comparison of parts fabricated from the multiple powder blends and gas atomized powder was made. It has been demonstrated that powder blending can produce fully dense parts in the Arcam system by utilizing the double melt technique or HIPing the built pars. The double melt technique increased the density of the sample part and modified the microstructure into finer martensitic grains. The HIP process can make a part fully dense regardless of what percentage of HDH powder blending is used. The HIP process yielded the same microstructure, regardless of the grain structure it started with. This research allows for the reduction of costs using titanium powders in the EBM system, but can also be implemented with more costly elements and alloys using other metal AM technologies. This includes niobium, tantalum, and nickel-based superalloys for use in various industries.

  2. Temperature dependence improvement of luminance in powder electroluminescent cells by modified BaTiO3 powders

    Microsoft Academic Search

    K. Tanaka; M. Toyoda

    1991-01-01

    Luminance of powder electroluminescent cells varies greatly with ambient temperature. This luminance instability can be improved by designing temperature-dependent impedance of an insulating layer. Attempts were made by using modified BaTiO3 ceramic powders as insulating materials. Luminance change has been suppressed below 8% at 20-70°C by a modified BaTiO3 powder having a negative temperature coefficient of the dielectric constant. Luminance

  3. Comparative study of doped ceria thin-film electrolytes prepared by wet powder spraying with powder synthesized via two techniques

    Microsoft Academic Search

    Huangang Shi; Wei Zhou; Ran Ran; Zongping Shao

    2010-01-01

    Fabrication of dense Sm0.2Ce0.8O1.9 (SDC) thin-film electrolytes by wet powder spraying in combination with high-temperature sintering is investigated. Two powder synthesis techniques, i.e., a hydrothermal synthesis and an EDTA–citrate complexing sol–gel process, were investigated. X-ray diffraction, BET surface area and laser particle size analysis demonstrate there is certain level of aggregation in both powders. However, it is more pronounced in

  4. Minimum ignition energy of nano and micro Ti powder in the presence of inert nano TiO? powder.

    PubMed

    Chunmiao, Yuan; Amyotte, Paul R; Hossain, Md Nur; Li, Chang

    2014-06-15

    The inerting effect of nano-sized TiO2 powder on ignition sensitivity of nano and micro Ti powders was investigated with a Mike 3 apparatus. "A little is not good enough" is also suitable for micro Ti powders mixed with nano-sized solid inertants. MIE of the mixtures did not significantly increase until the TiO2 percentage exceeded 50%. Nano-sized TiO2 powders were ineffective as an inertant when mixed with nano Ti powders, especially at higher dust loadings. Even with 90% nano TiO2 powder, mixtures still showed high ignition sensitivity because the statistic energy was as low as 2.1 mJ. Layer fires induced by ignited but unburned metal particles may occur for micro Ti powders mixed with nano TiO2 powders following a low level dust explosion. Such layer fires could lead to a violent dust explosion after a second dispersion. Thus, additional attention is needed to prevent metallic layer fires even where electric spark potential is low. In the case of nano Ti powder, no layer fires were observed because of less flammable material involved in the mixtures investigated, and faster flame propagation in nanoparticle clouds. PMID:24797905

  5. Nutritional composition of ginger powder prepared using various drying methods.

    PubMed

    Sangwan, A; Kawatra, A; Sehgal, S

    2014-09-01

    A study was undertaken to prepare ginger powder using various drying methods and their nutritional evaluation was carried out. Ginger (Zingiber officinale) was dried using shade, solar, oven and microwave drying methods. All the samples were ground in grinder to make fine powder. Sensory analysis indicated that acceptability of all types of ginger powders were in the range of 'liked very much' to 'liked moderately' by the panelists. The mean score obtained for colour was higher in shade dried ginger powder i.e., 8.20 as compared to oven dried (7.60), solar dried (7.70) and microwave dried ginger powder (7.80). Moisture content ranged from 3.55 % in solar dried ginger powder to 3.78 % in shade dried ginger powder. Slightly higher moisture content was found in shade dried ginger powder. Protein, crude fiber, fat and ash contents ranged from 5.02 to 5.82, 4.97 to 5.61, 0.76 to 0.90 and 3.38 to 3.66 %, respectively. ?-carotene and ascorbic acid content was found maximum in shade dried ginger powder i.e., 0.81 mg/100 g and 3.83 mg/100 g, respectively. Polyphenol content was almost similar in all the samples whereas calcium was slightly higher in the shade dried ginger powder i.e., 69.21 mg/100 g. Results have shown that ginger powder prepared from various drying methods had good sensory and nutritional profile. PMID:25190894

  6. Synthesis and sintering of nanocrystalline hydroxyapatite powders by citric acid sol–gel combustion method

    Microsoft Academic Search

    Yingchao Han; Shipu Li; Xinyu Wang; Xiaoming Chen

    2004-01-01

    The citric acid sol–gel combustion method has been used for the synthesis of nanocrystalline hydroxyapatite (HAP) powder from calcium nitrate, diammonium hydrogen phosphate and citric acid. The phase composition of HAP powder was characterized by X-ray powder diffraction analysis (XRD). The morphology of HAP powder was observed by transmission electron microscope (TEM). The HAP powder has been sintered into microporous

  7. Process for preparing titanium nitride powder

    DOEpatents

    Bamberger, C.E.

    1988-06-17

    A process for making titanium nitride powder by reaction of titanium phosphates with sodium cyanide. The process of this invention may comprise mixing one or more phosphates of Ti with a cyanide salt in the absence of oxygen and heating to a temperature sufficient to cause reaction to occur. In the preferred embodiment the ratio of cyanide salt to Ti should be at least 2 which results in the major Ti-containing product being TiN rather than sodium titanium phosphate byproducts. The process is an improvement over prior processes since the byproducts are water soluble salts of sodium which can easily be removed from the preferred TiN product by washing. 2 tabs.

  8. Structural color painting by rubbing particle powder.

    PubMed

    Park, ChooJin; Koh, Kunsuk; Jeong, Unyong

    2015-01-01

    Structural colors originate from purely physical structures. Scientists have been inspired to mimic the structures found in nature, the realization of these structures still presents a great challenge. We have recently introduced unidirectional rubbing of a dry particle powder on a rubbery surface as a quick, highly reproducible means to fabricate a single crystal monolayer assembly of particles over an unlimited area. This study extends the particle-rubbing process to a novel fine-art painting, structural color painting (SCP). SCP is based on structural coloring with varying iridescence according to the crystal orientation, as controlled by the rubbing direction. This painting technique can be applied on curved surfaces, which enriches the objects to be painted and helps the painter mimic the structures found in nature. It also allows for quick fabrication of complicated particle-assembly patterns, which enables replication of paintings. PMID:25661669

  9. Structural Color Painting by Rubbing Particle Powder

    PubMed Central

    Park, ChooJin; Koh, Kunsuk; Jeong, Unyong

    2015-01-01

    Structural colors originate from purely physical structures. Scientists have been inspired to mimic the structures found in nature, the realization of these structures still presents a great challenge. We have recently introduced unidirectional rubbing of a dry particle powder on a rubbery surface as a quick, highly reproducible means to fabricate a single crystal monolayer assembly of particles over an unlimited area. This study extends the particle-rubbing process to a novel fine-art painting, structural color painting (SCP). SCP is based on structural coloring with varying iridescence according to the crystal orientation, as controlled by the rubbing direction. This painting technique can be applied on curved surfaces, which enriches the objects to be painted and helps the painter mimic the structures found in nature. It also allows for quick fabrication of complicated particle-assembly patterns, which enables replication of paintings. PMID:25661669

  10. Apparatus for producing nanoscale ceramic powders

    DOEpatents

    Helble, Joseph J. (Andover, MA); Moniz, Gary A. (Windham, NH); Morse, Theodore F. (Little Compton, RI)

    1995-09-05

    An apparatus provides high temperature and short residence time conditions for the production of nanoscale ceramic powders. The apparatus includes a confinement structure having a multiple inclined surfaces for confining flame located between the surfaces so as to define a flame zone. A burner system employs one or more burners to provide flame to the flame zone. Each burner is located in the flame zone in close proximity to at least one of the inclined surfaces. A delivery system disposed adjacent the flame zone delivers an aerosol, comprising an organic or carbonaceous carrier material and a ceramic precursor, to the flame zone to expose the aerosol to a temperature sufficient to induce combustion of the carrier material and vaporization and nucleation, or diffusion and oxidation, of the ceramic precursor to form pure, crystalline, narrow size distribution, nanophase ceramic particles.

  11. Apparatus for producing nanoscale ceramic powders

    DOEpatents

    Helble, Joseph J. (Andover, MA); Moniz, Gary A. (Windham, NH); Morse, Theodore F. (Little Compton, RI)

    1997-02-04

    An apparatus provides high temperature and short residence time conditions for the production of nanoscale ceramic powders. The apparatus includes a confinement structure having a multiple inclined surfaces for confining flame located between the surfaces so as to define a flame zone. A burner system employs one or more burners to provide flame to the flame zone. Each burner is located in the flame zone in close proximity to at least one of the inclined surfaces. A delivery system disposed adjacent the flame zone delivers an aerosol, comprising an organic or carbonaceous carrier material and a ceramic precursor, to the flame zone to expose the aerosol to a temperature sufficient to induce combustion of the carrier material and vaporization and nucleation, or diffusion and oxidation, of the ceramic precursor to form pure, crystalline, narrow size distribution, nanophase ceramic particles.

  12. Structural Color Painting by Rubbing Particle Powder

    NASA Astrophysics Data System (ADS)

    Park, Choojin; Koh, Kunsuk; Jeong, Unyong

    2015-02-01

    Structural colors originate from purely physical structures. Scientists have been inspired to mimic the structures found in nature, the realization of these structures still presents a great challenge. We have recently introduced unidirectional rubbing of a dry particle powder on a rubbery surface as a quick, highly reproducible means to fabricate a single crystal monolayer assembly of particles over an unlimited area. This study extends the particle-rubbing process to a novel fine-art painting, structural color painting (SCP). SCP is based on structural coloring with varying iridescence according to the crystal orientation, as controlled by the rubbing direction. This painting technique can be applied on curved surfaces, which enriches the objects to be painted and helps the painter mimic the structures found in nature. It also allows for quick fabrication of complicated particle-assembly patterns, which enables replication of paintings.

  13. Synchrotron X-Ray Powder Diffraction

    NASA Astrophysics Data System (ADS)

    Gozzo, Fabia

    The large breadth of the Synchrotron Radiation X-ray Powder Diffraction (SR-XRPD) technique inevitably requires that we make a certain number of choices in its discussion. Assuming you already have some knowledge of SR and XRPD, we explore the peculiar features that arise from combining them. From the perspective of a beamline scientist, we discuss aspects influencing the beamline optics, diffractometer, detectors and sample environments with attention to details important to perform outstanding SR-XRPD experiments. We begin with a brief overview of SR characteristics and properties and finish with a few SR-XRPD highlights. An extensive literature citation is provided for those who want to delve deeper into those topics that are inevitably not completely covered here.

  14. From Powders to Thermally Sprayed Coatings

    NASA Astrophysics Data System (ADS)

    Fauchais, Pierre; Montavon, Ghislain; Bertrand, Ghislaine

    2010-01-01

    Since the early stages of thermal spray, it has been recognized that the powder composition, size distribution, shape, mass density, mechanical resistance, components distribution for composite particles play a key role in coating microstructure and thermo mechanical properties. The principal characteristics of particles are strongly linked to the manufacturing process. Coatings also depend on the process used to spray particles and spray parameters. Many papers have been devoted to the relationships existing between coating properties and structures at different scales and manufacturing processes. In many conventional spray conditions resulting in micrometric structures, among the different parameters, good powder flow ability, and dense particles are important features. Thermal plasma treatment, especially by RF plasma, of particles, prepared by different manufacturing processes, allows achieving such properties and it is now developed at an industrial scale. Advantages and drawbacks of this process will be discussed. Another point, which will be approached, is the self-propagating high-temperature synthesis, depending very strongly upon the starting composite particle manufacturing. However, as everybody knows, "small is beautiful" and nano- or finely structured coatings are now extensively studied with spraying of: (i) very complex alloys containing multiple elements which exhibit a glass forming capability when cooled-down, their under-cooling temperature being below the glass transition temperature; (ii) conventional micrometer-sized particles (in the 30-90 ?m range) made of agglomerated nanometer-sized particles; (iii) sub-micrometer- or nanometer-sized particles via a suspension in which also, instead of particles, stable sol of nanometer-sized particles can be introduced; and (iv) spray solutions of final material precursor. These different processes using plasma, HVOF or sometimes flame and also cold-gas spray will be discussed together with the production of nanometer-sized particles via the chemical reaction method or by a special type of milling: the cryogenic milling process often referred to as "cryomilling."

  15. Temperature distribution in powder beds during 3D printing

    Microsoft Academic Search

    M. Dressler; M. Röllig; M. Schmidt; A. Maturilli; J. Helbert

    2010-01-01

    Purpose – This purpose of this paper is to report about the temperature distribution in metal and ceramic powder beds during 3D printing. The differing powders are thoroughly characterized in terms of thermal conductivity, thermal diffusivity, emissivity spectra and density. Design\\/methodology\\/approach – The temperature distribution was measured in a 3D printing appliance (Prometal R1) with the help of thin thermocouples

  16. Densification of powder metallurgy billets by a roll consolidation technique

    NASA Technical Reports Server (NTRS)

    Sellman, W. H.; Weinberger, W. R.

    1973-01-01

    Container design is used to convert partially densified powder metallurgy compacts into fully densified slabs in one processing step. Technique improves product yield, lowers costs and yields great flexibility in process scale-up. Technique is applicable to all types of fabricable metallic materials that are produced from powder metallurgy process.

  17. Application of superalloy powder metallurgy for aircraft engines

    NASA Technical Reports Server (NTRS)

    Dreshfield, R. L.; Miner, R. V., Jr.

    1980-01-01

    The results of the Materials for Advanced Turbine Engines (MATE) program initiated by NASA are presented. Mechanical properties comparisons are made for superalloy parts produced by as-HIP powder consolidation and by forging of HIP consolidated billets. The effect of various defects on the mechanical properties of powder parts are shown.

  18. An improved method for shock consolidation of powders

    Microsoft Academic Search

    M. A. MEYERS; S. L. WANG

    1988-01-01

    A technique for shock consolidation of powders was developed. This technique uses the cylindrical geometry with two co-axial tubes. The powder is contained in the internal tube. The external tube is surrounded by the explosive charge, which is detonated at one end; this external tube acts as a flyer tube, impacting the internal tube. This technique generates pressures in the

  19. Modeling resistive heating of powdered uranium dioxide. [Fuel vaporization

    Microsoft Academic Search

    R. M. Train; S. Ishikawa; R. J. Keeth; M. P. Manning

    1974-01-01

    Equations for heat transfer with simultaneous electric power dissipation through five concentric cylindrical annuli were formulated for temperature variation in the radial direction only. The equations were developed to simulate an experimental apparatus for vaporization of powdered uranium dioxide in the center annulus. The effect of varying the power inputs, containment sleeve material, void fraction in the powder, and external

  20. Mystery Powders: An Introduction to Physical and Chemical Properties

    NSDL National Science Digital Library

    Leah Bulver

    In this classroom guided inquiry lesson, students will complete a serious of tests using five different mystery powders. Student will develop hypotheses, make observations, and draw conclusions about what each powder is and the physical and chemical reactions that occur when heat, water, iodine, and vinegar are added to each substance.

  1. Impact of dairy protein powders on biscuit quality

    Microsoft Academic Search

    Eimear Gallagher; Sheila Kenny; Elke K. Arendt

    2005-01-01

    The effects of whey protein concentrate and sodium caseinate (NaCas) on a short dough biscuit formulation were investigated with respect to dough characteristics and final product quality. Dairy powders were added at levels of 5, 10 and 15% of flour weight. Addition of 5 and 10% dairy protein powders reduced dough hardness. Doughs containing 10 and 15% NaCas had significantly

  2. Immunodetection of added glycomacropeptide in milk formulas and milk powders.

    PubMed

    Oancea, Simona; Stoia, Mihaela

    2011-01-01

    The present study aimed the detection of fraudulent manipulation of milk powder with a low cost component--whey powder, by applying the immunochromatographic assay to identify glycomacropeptide. Five commercial milk powder samples of various brands from the national market were analyzed: lactose enriched milk powder type 26, two whole milk powders, vitamin enriched milk powder and full cream milk powder. Our results showed additional whey (1-2%) in 60% of the selected samples after casein removal by precipitation with 20% trichloracetic acid. Another investigated sample--the enriched UHT milk for children aged 4-12 years--proved addition of whey. Other two commercial toddler formula milk powder samples of different brands were used for comparison for the presence of glycomacropeptide. The first sample which was regularly labeled as containing whey protein concentrate was found positive for glycomacropeptide in accordance with the label information, while the second one not containing whey proteins as specified by the product label, was found negative for glycomacropeptide, these two samples being in accordance with the actual legislation. PMID:21717808

  3. ORIGINAL PAPER Fast crystallization of lactose and milk powder

    E-print Network

    Paris-Sud XI, Université de

    °C and 80% relative humidity, but they also found that the proteins and salts in whey and wheyORIGINAL PAPER Fast crystallization of lactose and milk powder in fluidized bed dryer Abstract The rationale of this study has been to produce stabilized dairy powders for longer-term ambient

  4. 21 CFR 520.154c - Bacitracin zinc soluble powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Bacitracin zinc soluble powder. 520.154c Section...ANIMAL DRUGS § 520.154c Bacitracin zinc soluble powder. (a) Specifications...perfringens susceptible to bacitracin zinc. (B) Limitations . Prepare a...

  5. 21 CFR 520.154c - Bacitracin zinc soluble powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Bacitracin zinc soluble powder. 520.154c Section...ANIMAL DRUGS § 520.154c Bacitracin zinc soluble powder. (a) Specifications...perfringens susceptible to bacitracin zinc. (B) Limitations . Prepare a...

  6. 21 CFR 520.154c - Bacitracin zinc soluble powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Bacitracin zinc soluble powder. 520.154c Section...ANIMAL DRUGS § 520.154c Bacitracin zinc soluble powder. (a) Specifications...perfringens susceptible to bacitracin zinc. (B) Limitations. Prepare a...

  7. 21 CFR 520.154c - Bacitracin zinc soluble powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Bacitracin zinc soluble powder. 520.154c Section...ANIMAL DRUGS § 520.154c Bacitracin zinc soluble powder. (a) Specifications...perfringens susceptible to bacitracin zinc. (B) Limitations . Prepare a...

  8. Carbon nanoshells obtained from leaching carbonyl nickel metal powders

    Microsoft Academic Search

    Zbigniew S. Wronski; Graham J. C. Carpenter

    2006-01-01

    Certain carbonyl nickel powders manufactured by the Mond chemical vapour deposition process are coated with a nanometric layer of defected graphitic carbon. Through a simple chemical process of acid leaching of the nickel metal a dry filtrate is obtained, which consists of carbon nanopowder. As imaged in a transmission electron microscope, the powder consists of nanostructured hollow carbon shells, termed

  9. Here are procedures for handling persistent black-powder contamination

    Microsoft Academic Search

    1998-01-01

    Recent research into black powder problems experienced by natural-gas transmission pipelines indicates steps that can be taken to control the material in gas pipelines, gathering systems, and storage facilities. Black powder (the common term for various forms of iron sulfide mixed with contaminants) is the least understood but most prominent contaminant in natural-gas pipelines and compression equipment in pipeline, refinery,

  10. X-ray diffraction investigation of ultrafine boron nitride powders

    SciTech Connect

    Gurov, S.V.; Chukalin, V.I.; Rezchikova, T.V.; Torbov, V.J.; Troitskii, V.N.

    1986-01-01

    This paper presents an x-ray diffraction analysis of ultrafine boron nitride powders of different mean particle sizes. Diffraction spectra of the ultrafine boron nitride powders were obtained using a DRON-1 apparatus. The experimental facts are indicative of a turbostratic character of deformation of the hexagonal lattice of ultrafinely divided boron nitride.

  11. RESEARCH ARTICLES Dry Powder Inhaler Device Influence on Carrier Particle

    E-print Network

    Raman, Venkat

    RESEARCH ARTICLES Dry Powder Inhaler Device Influence on Carrier Particle Performance MARTIN J.com). DOI 10.1002/jps.22824 ABSTRACT: Dry powder inhalers (DPIs) are distinguished from one another the role of carrier particle size and shape on inhaler performance. Two percent (w/w) binary blends

  12. Dry Powder Inhaler Device Influence on Carrier Particle Performance

    E-print Network

    Raman, Venkat

    Dry Powder Inhaler Device Influence on Carrier Particle Performance MARTIN J. DONOVAN,1 SIN HYEN (wileyonlinelibrary.com). DOI 10.1002/jps.22824 ABSTRACT: Dry powder inhalers (DPIs) are distinguished from one the role of carrier particle size and shape on inhaler performance. Two percent (w/w) binary blends

  13. Food powders flowability characterization: theory, methods, and applications.

    PubMed

    Juliano, Pablo; Barbosa-Cánovas, Gustavo V

    2010-01-01

    Characterization of food powders flowability is required for predicting powder flow from hoppers in small-scale systems such as vending machines or at the industrial scale from storage silos or bins dispensing into powder mixing systems or packaging machines. This review covers conventional and new methods used to measure flowability in food powders. The method developed by Jenike (1964) for determining hopper outlet diameter and hopper angle has become a standard for the design of bins and is regarded as a standard method to characterize flowability. Moreover, there are a number of shear cells that can be used to determine failure properties defined by Jenike's theory. Other classic methods (compression, angle of repose) and nonconventional methods (Hall flowmeter, Johanson Indicizer, Hosokawa powder tester, tensile strength tester, powder rheometer), used mainly for the characterization of food powder cohesiveness, are described. The effect of some factors preventing flow, such as water content, temperature, time consolidation, particle composition and size distribution, is summarized for the characterization of specific food powders with conventional and other methods. Whereas time-consuming standard methods established for hopper design provide flow properties, there is yet little comparative evidence demonstrating that other rapid methods may provide similar flow prediction. PMID:22129336

  14. High-porosity powder-fiber composite materials

    Microsoft Academic Search

    A. G. Kostornov; N. E. Fedorova; L. I. Chernyshev

    1983-01-01

    The feasibility is demonstrated of substantially reducing volume changes during the sintering of high-porosity materials by the addition of fibers to a powder mixture. The mechanism of sintering of powder-fiber composites containing more than 25% of fibers is similar to the mechanism of sintering of pure fiber materials. The mechanical properties of permeable composite materials are determined by the fiber

  15. Mathematical modeling of powder paint particle trajectories in electrostatic painting

    Microsoft Academic Search

    F. Sharmene Ali; Terence E. Base; Ion I. Inculet

    2000-01-01

    The trajectories of charged powder particles in an electrostatic powder coating system were modeled considering electrical and fluid forces. The mathematical model employed an iterative technique wherein the charge simulation method was used to compute the electric field strength and the method of characteristics was used to compute the charge density in the gun-to-target region. The fluid flow between the

  16. Maximum electrostatic charge of powder in pipe flow

    Microsoft Academic Search

    Tatsushi Matsuyama; Hideo Yamamoto

    2010-01-01

    In dry powder process, particles collide against each other and onto wall, and normally, electrostatic charge is generated. Such a process is called trioelectrification or tribo-\\/contact-\\/impact-charging of particles. In this paper, the amount of maximum (or saturated or equilibrium) charge on a particle in a powder flow of a pneumatic conveyer with a metal pipe was discussed. A theoretical discussion

  17. Mechanical etching of micro pockets by powder blasting

    Microsoft Academic Search

    D. S. Park; T. I. Seo; M. W. Cho

    2005-01-01

    The main objective of this research is to develop a mechanical etching technique to produce micro mould dies having micro pockets of hundreds of µm. A powder blasting technique is applied to stainless steel plates based on predefined process conditions. This paper describes the performance of a powder blasting technique and the effect of the number of nozzle scanning times

  18. 84. BUILDING NO. 561, LOOKING SOUTHEAST AT CANNON POWDER BLENDER ...

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

    84. BUILDING NO. 561, LOOKING SOUTHEAST AT CANNON POWDER BLENDER FROM ACROSS PICATINNY LAKE. LOUVERED WALL FACING LAKE WAS DESIGNED TO RELIEVE BLASTS AND DIRECT THEM TOWARD LAKE IF THEY OCCURRED. - Picatinny Arsenal, 500 Area, Powder Factory & Power House, State Route 15 near I-80, Dover, Morris County, NJ

  19. Consolidation of amorphous oxide powders using spark plasma sintering

    Microsoft Academic Search

    Daniela Marisa Fredrick

    2009-01-01

    The objective of this study is to synthesize amorphous oxide powders and sinter the systems close to or at theoretical density for optical transparency while retaining the amorphous structure using the Spark Plasma Sintering (SPS) method. In addition, the parameters that govern the formation of these systems were investigated. The main powder processing techniques are sol-gel, flame-spaying and spherodizing. The

  20. THERMAL CONDUCTIVITY OF POWDER INSULATIONS FOR CRYOGENIC STORAGE

    E-print Network

    Chang, Ho-Myung

    THERMAL CONDUCTIVITY OF POWDER INSULATIONS FOR CRYOGENIC STORAGE VESSELS Y. S. Choi1 '3 , M. N), powder insulation, and foam insulation, are used in the cryogenic storage vessels. Among CP823, Advances in Cjyogenie Engineering: Transactions of the Cryogenic Engineering Conference - CEC, Vol. 51, edited by J. G

  1. Novelties in physics of explosive welding and powder compaction

    Microsoft Academic Search

    I. Plaksin; J. Campos; J. Ribeiro; R. Mendes; J. Direito; D. Braga; R. Pruemmer

    2003-01-01

    Widely known technologies of explosive (X) welding and explosive (X) powder compaction are based on applications of porous composite solid or liquid explosives. Recent results on dynamics of X-welding and X-powder compaction are presented and discussed in this paper in the conceptual context of an orderly oscillating detonation wave (DW), a synergetic phenomenon observed in detonation of all classes of

  2. Mathematical modeling of powder-snow avalanche flows

    E-print Network

    Mathematical modeling of powder-snow avalanche flows Denys Dutykh a, aLAMA, UMR 5127 CNRS´e de Savoie, 73376 Le Bourget-du-Lac Cedex, France Abstract Powder-snow avalanches are violent natural. In this study we present a novel model for the simulation of avalanches in the aerosol regime. The second scope

  3. Dispersion of carbon nanotubes (CNTs) in aluminum powder

    Microsoft Academic Search

    A. Esawi; K. Morsi

    2007-01-01

    In the present work, we use mechanical alloying (MA) for the first time to generate a homogenous distribution of 2wt% CNT within Al powders. The effect of milling time (up to 48h) on the morphological development of the powders and dispersion of CNTs was investigated. The results show that the technique is effective in dispersing the nanotubes within the soft

  4. NOTES AND COMMENTS Revisiting powdered sugar for varroa control on

    E-print Network

    Delaplane, Keith S.

    NOTES AND COMMENTS Revisiting powdered sugar for varroa control on honey bees (Apis mellifera L, accepted for publication 1 September 2012. Keywords: Varroa destructor, IPM, powdered sugar, dusts Journal sugar has been examined as a remedial control for Varroa destructor Anderson and Trueman (varroa). Two

  5. Rapid flow cytometry analysis of antimicrobial properties of nettle powder and cranberry powder

    NASA Astrophysics Data System (ADS)

    Hattuniemi, Maarit; Korhonen, Johanna; Jaakkola, Mari; Räty, Jarkko; Virtanen, Vesa

    2010-11-01

    Both nettle (Urtica dioica) and cranberry (Vaccinium oxycoccus) are widely known to have good influence on health. The aim of this study was to investigate antimicrobial properties of nettle powder and cranberry powder against Escherichia coli (E. coli) and monitor the growth of the bacteria by a rapid flow cytometry (FCM) method. For FCM measurements samples were stained with fluorescent dyes. The inhibitory effects of plant material on growth of E. coli were estimated by comparing the results of control sample (E. coli) to E. coli samples with plant material. FCM offers both a brilliant tool to investigate the kinetics of the growth of bacterium, since subsamples can be taken from the same liquid medium during the growing period and with fluorescent dyes a rapid method to investigate viability of the bacterium.

  6. Whole Genome Sequencing and Analysis of Plant Growth Promoting Bacteria Isolated from the Rhizosphere of Plantation Crops Coconut, Cocoa and Arecanut

    PubMed Central

    Thomas, George V.; Manikandan, Vinu; Gajewski, John; Thomas, George; Seshagiri, Somasekar; Schuster, Stephan C.

    2014-01-01

    Coconut, cocoa and arecanut are commercial plantation crops that play a vital role in the Indian economy while sustaining the livelihood of more than 10 million Indians. According to 2012 Food and Agricultural organization's report, India is the third largest producer of coconut and it dominates the production of arecanut worldwide. In this study, three Plant Growth Promoting Rhizobacteria (PGPR) from coconut (CPCRI-1), cocoa (CPCRI-2) and arecanut (CPCRI-3) characterized for the PGP activities have been sequenced. The draft genome sizes were 4.7 Mb (56% GC), 5.9 Mb (63.6% GC) and 5.1 Mb (54.8% GB) for CPCRI-1, CPCRI-2, CPCRI-3, respectively. These genomes encoded 4056 (CPCRI-1), 4637 (CPCRI-2) and 4286 (CPCRI-3) protein-coding genes. Phylogenetic analysis revealed that both CPCRI-1 and CPCRI-3 belonged to Enterobacteriaceae family, while, CPCRI-2 was a Pseudomonadaceae family member. Functional annotation of the genes predicted that all three bacteria encoded genes needed for mineral phosphate solubilization, siderophores, acetoin, butanediol, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, chitinase, phenazine, 4-hydroxybenzoate, trehalose and quorum sensing molecules supportive of the plant growth promoting traits observed in the course of their isolation and characterization. Additionally, in all the three CPCRI PGPRs, we identified genes involved in synthesis of hydrogen sulfide (H2S), which recently has been proposed to aid plant growth. The PGPRs also carried genes for central carbohydrate metabolism indicating that the bacteria can efficiently utilize the root exudates and other organic materials as energy source. Genes for production of peroxidases, catalases and superoxide dismutases that confer resistance to oxidative stresses in plants were identified. Besides these, genes for heat shock tolerance, cold shock tolerance and glycine-betaine production that enable bacteria to survive abiotic stress were also identified. PMID:25162593

  7. Compressibility and compactibility of powdered polymers: poly(vinyl chloride) powders

    Microsoft Academic Search

    Anne-France Rime; Danielle Massuelle; Frank Kubel; Hans-Rudolf Hagemann; Eric Doelker

    1997-01-01

    The present investigation is concerned with the possible effects of material-related properties (molecular mass, glass transition and melting temperatures, crystallinity, tacticity) and particle-related properties (shape, size, specific surface area) on the compression characteristics of the chosen model polymer powder: poly(vinyl chloride) (PVC). Four grades were selected known in literature for providing compacts of varied mechanical strength. The compression characteristics were

  8. Understanding the strength of hot-pressed nanostructured powder compacts

    SciTech Connect

    Rawers, J.C. [Dept. of Energy, Albany, OR (United States). Albany Research Center] [Dept. of Energy, Albany, OR (United States). Albany Research Center; Harlow, D.G. [Lehigh Univ., Bethlehem, PA (United States)] [Lehigh Univ., Bethlehem, PA (United States)

    1999-02-01

    Attrition-milled nanostructured powders were hot pressed, and macroscopic properties of density, hardness, grain size, and strength were measured. No correlation was found between processing conditions (temperature and time) used in this study and compact properties, nor was a correlation found between the tensile (or failure) stress and density, hardness, or grain size. Variations of compact properties of unmilled powder were similar to that of milled powders. Tensile data were not well fitted to a Gaussian distribution but were well fitted to a two-parameter Weibull distribution. Thus, although the milled powder compacts had an average tensile strength greater than the unmilled powder compacts, all sample compositions fit a distribution with zero as a possible minimal stress level. Weibull analysis suggests that the tensile and compression strength is controlled by the presence of fine cracks, which may limit future engineering applications. Efforts to eliminate these cracks during hot pressing were unsuccessful.

  9. Powder wettability at a static air-water interface.

    PubMed

    Dupas, Julien; Forny, Laurent; Ramaioli, Marco

    2015-06-15

    The reconstitution of a beverage from a dehydrated powder involves several physical mechanisms that determine the practical difficulty to obtain a homogeneous drink in a convenient way and within an acceptable time for the preparation of a beverage. When pouring powder onto static water, the first hurdle to overcome is the air-water interface. We propose a model to predict the percentage of powder crossing the interface in 45 s, namely the duration relevant for this application. We highlight theoretically the determinant role of the contact angle and of the particle size distribution. We validate experimentally the model for single spheres and use it to predict the wettability performance of commercial food powders for different contact angles and particles sizes. A good agreement is obtained when comparing the predictions and the wettability of the tested powders. PMID:25721855

  10. Indentation test for free-flowable powder excipients.

    PubMed

    Zatloukal, Zdenek; Sklubalová, Zdenka

    2008-01-01

    Indentation of a sphere into nonconsolidated powder excipients is a suitable complementary method for the evaluation of flow properties of the free-flowable noncohesive powders. To use the standard penetrometry method to indentation of nonconsolidated powder layer by a glass sphere of 16 mm in diameter, the suitable geometry of the measurement container is required to prevent undesirable moving in a direction opposite to that in which the indenting sphere moves. Thus, the powder indentation by a sphere seems to be similar to indentation by the Brinell hardness tester. In this work, the depth of indentation was measured for five pharmaceutical powder excipients: sodium chloride, sodium citrate, potassium citrate, sorbitol, and boric acid with the three size fractions in the range of 0.315-0.630 mm. To express powder flowability, the uniform mass and/or volume flow rate from the 10-mm cylindrical outlet of the cylindrical testing hopper was used. The relationships between the powder flow rate and its bulk density and/or the different characteristics of indentation were modeled by using linear regression. Out of the indentation characteristics, the mass of indentation calculated as the multiple of the volume of indentation and the powder bulk density could be recommended to estimate the powder mass flow rate due to the linear regression with the coefficient of determination equal to 0.973 and the accuracy of 4.3%. In conclusion, the indentation by the sphere could be recommended as a quick simple method for the comparison of flow properties of the nonconsolidated, noncohesive powder excipients. PMID:18300103

  11. 30 CFR 75.1101-14 - Installation of dry powder chemical systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Self-contained dry powder chemical systems shall be...components of each dry powder chemical system shall be a type...or Factory Mutual Engineering Corp. (c) The components of each dry powder chemical system shall be...

  12. Multi-scale current activated tip-based sintering of powder-based materials

    E-print Network

    El Desouky, Ahmed Mohamed

    2012-01-01

    in turn conducts heat to the powder) which is responsibleoxide powders where the electric current is used to heat upheat conduction. Since all the materials used in this dissertation were electrically conducting metallic powders,

  13. 30 CFR 75.1101-15 - Construction of dry powder chemical systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 2011-07-01 false Construction of dry powder chemical systems. 75.1101-15...Protection § 75.1101-15 Construction of dry powder chemical systems. (a) Each self-contained dry powder system shall be equipped with...

  14. 30 CFR 75.1101-17 - Sealing of dry powder chemical systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Sealing of dry powder chemical systems. 75.1101-17 Section... Fire Protection § 75.1101-17 Sealing of dry powder chemical systems. Each dry powder chemical system shall be adequately...

  15. 30 CFR 75.1101-13 - Dry powder chemical systems; general.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 2011-07-01 2011-07-01 false Dry powder chemical systems; general. 75...MINES Fire Protection § 75.1101-13 Dry powder chemical systems; general. Self-contained dry powder chemical systems may be installed...

  16. 30 CFR 75.1101-13 - Dry powder chemical systems; general.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 2010-07-01 false Dry powder chemical systems; general. 75...MINES Fire Protection § 75.1101-13 Dry powder chemical systems; general. Self-contained dry powder chemical systems may be installed...

  17. 30 CFR 75.1101-14 - Installation of dry powder chemical systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Self-contained dry powder chemical systems shall be...components of each dry powder chemical system shall be a type...or Factory Mutual Engineering Corp. (c) The components of each dry powder chemical system shall be...

  18. Homogeneous Precipitation of Nickel Hydroxide Powders

    SciTech Connect

    Bora Mavis

    2003-12-12

    Precipitation and characterization of nickel hydroxide powders were investigated. A comprehensive precipitation model incorporating the metal ion hydrolysis, complexation and precipitation reactions was developed for the production of the powders with urea precipitation method. Model predictions on Ni{sup 2+} precipitation rate were confirmed with precipitation experiments carried out at 90 C. Experimental data and model predictions were in remarkable agreement. Uncertainty in the solubility product data of nickel hydroxides was found to be the large contributor to the error. There were demonstrable compositional variations across the particle cross-sections and the growth mechanism was determined to be the aggregation of primary crystallites. This implied that there is a change in the intercalate chemistry of the primary crystallites with digestion time. Predicted changes in the concentrations of simple and complex ions in the solution support the proposed mechanism. The comprehensive set of hydrolysis reactions used in the model described above allows the investigation of other systems provided that accurate reaction constants are available. the fact that transition metal ions like Ni{sup 2+} form strong complexes with ammonia presents a challenge in the full recovery of the Ni{sup 2+}. On the other hand, presence of Al{sup 3+} facilitates the complete precipitation of Ni{sup 2+} in about 3 hours of digestion. A challenge in their predictive modeling studies had been the fact that simultaneous incorporation of more than one metal ion necessitates a different approach than just using the equilibrium constants of hydrolysis, complexation and precipitation reactions. Another limitation of using equilibrium constants is that the nucleation stage of digestion, which is controlled mainly by kinetics, is not fully justified. A new program released by IBM Almaden Research Center (Chemical Kinetics Simulator{trademark}, Version 1.01) lets the user change the order of kinetic components of a reaction which was set to stoichiometric constant with which the species appear in the reaction in KINSIM by default. For instance, in the case of LDH precipitation, the new program allows to change the order of species in the reactions associated with Al{sup 3+} and let the Ni{sup 2+} reactions take over. This could be carried on iteratively until a good fit between the experimental data and the predictions were observed. However for such studies availability of accurate equilibrium constants (especially for the solubility products for the solid phase) is a prerequisite.

  19. A comparison of the sintering of various titanium powders

    SciTech Connect

    Gerdemann, Stephen J.; Alman, David E.

    2005-02-01

    Recently, there has been renewed interest in low-cost titanium. Near-net-shape powder metallurgy offers the potential of manufacturing titanium articles without costly and difficult forming and machining operations; hence, processing methods such as conventional press- and-sinter, powder forging and powder injection molding are of interest. The sintering behavior of a variety of commercial and experimental titanium powders was studied. Commercial powders were acquired that were produced different routes: (i) sponge fines from the primary titanium processing; (ii) via the hydride-dehydride process; and (iii) gas atomization. The influence of vacuum sintering time (0.5 to 32 hrs) and temperature (1200, 1275 or 1350°C) on the microstructure (porosity present) of cold pressed powders was studied. The results are discussed in terms of the difference in powder characteristics; with the aim of identify the characteristics required for full density via press-and-sinter processing. Near-net-shape tensile bars were consolidated via cold pressed and sintered. After sintering, a sub-set of the tensile bars was hot-isostatic pressed (HIPed). The microstructure and properties of the bars were compared in the sintered and HIPed conditions.

  20. rf plasma synthesis of ultrafine, ultrapure silicon carbide powder

    SciTech Connect

    Hollabaugh, C.M.; Hull, D.E.; Newkirk, L.R.; Petrovic, J.J.

    1983-01-01

    Ultrafine, ultrapure silicon carbide powder has been produced by reaction of silane and methane in a high temperature rf plasma. Preliminary studies include the effect of gas composition and of powder (plasma temperature) on the stoichiometry of the powder. The carbon-to-silicon ratio of the powder was varied from 1.0 to 1.9 by changing the process conditions. The powder has a BET surface area of 101 m/sup 2//g, which is equivalent to a particle diameter of 18.5 nm. A particle size in the range of 10 to 20 nm was measured by transmission electron microscopy. X-ray diffraction results indicate a domain size of 7.5 nm and a crystal structure of beta (cubic) silicon carbide. Spectrographic analysis shows that metallic impurities are lower than high quality grade commercial powder. Because of the high surface area, the powder must be stored and processed in an inert atmosphere to prevent severe contamination with oxygen.