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Sieves
Kinds of Sieves Terms modified by Sieves Selected AbstractsMilk Protein Analysis Using a Micro Fabricated Sieve: A Promising PossibilityJOURNAL OF FOOD SCIENCE, Issue 3 2001C.S. Rao ABSTRACT: In cheese making, proteins present in the micellar phase, i.e., ,, ,, ,, , casein and their variants, determine the yield and properties of the final product (Walsh and others 1995). The current milk prices are based on solid components, that is, fat, total protein and other solids. However, the cheese yields are extremely sensitive to variations in protein sub-components. Thus, total protein content, although a simple measure of yield, is not the most accurate one. In the future, the food industry might require simple tools to analyze protein components in a given sample of milk. Two features of such a tool, portability and accuracy, would be invaluable. In this article, a protocol for design of a micro-scale sieve for the separation of proteins is conceived. [source] Pores in the Sieve and Channels in the Wall: Control of Paracellular Permeability by Junctional Proteins in Endothelial CellsMICROCIRCULATION, Issue 3 2001GIANFRANCO BAZZONI ABSTRACT Exchange of solutes and ions between the luminal and abluminal compartments of the circulation is critically dependent on the barrier properties of the vascular endothelium. Transport of solutes and fluids occurs along the transcellular and paracellular pathways that are mediated by intracellular vesicles and intercellular junctions, respectively. Although the ability of endothelial cells to dynamically regulate permeability has long been recognized, the precise mechanism and the signaling pathways involved have not been fully elucidated. Finally, current definition of the complex molecular composition of intercellular junctions is expected to explain the difference in permeability between diverse segments of the circulation and possibly to highlight the existence of specific junctional channels. The properties of junctional adhesion molecule-1 (JAM-1) and vascular endothelial cadherin (VE-cadherin), two transmembrane components of interendothelial junctions, are described in detail. [source] Innentitelbild: Ionothermal Synthesis of an Aluminophosphate Molecular Sieve with 20-Ring Pore Openings (Angew. Chem.ANGEWANDTE CHEMIE, Issue 31 201031/2010) Das kristalline Aluminophosphat-Molekularsieb mit den bislang größten Porenöffnungen (20MR), DNL-1, wurde synthetisiert. In ihrer Zuschrift auf S. 5495,ff. beschreiben Z. Tian et,al. die Ionothermalsynthese von DNL-1 und dessen Strukturbestätigung durch Rietveld-Verfeinerung der PXRD- und NMR-Analyse. Anders als das Zeolithanalogon von Gallophosphat, Cloverit, ist DNL-1 ausgezeichnet stabil, was einen Einsatz für Trennungen, Katalysen und zur Gasspeicherung möglich machen könnte. [source] Ionothermal Synthesis of an Aluminophosphate Molecular Sieve with 20-Ring Pore Openings,ANGEWANDTE CHEMIE, Issue 31 2010Ying Wei Aufnahmebereit: Das erste Aluminophosphat-Molekularsieb mit 20-gliedrigen Porenöffnungen wurde durch Ionothermalsynthese in Gegenwart zweier Strukturbildner erhalten (siehe Bild; H,weiß, C,türkis, N,blau). Das Material verfügt über ein viel stabileres -CLO-Gerüst als sein GaPO4 -Analogon Cloverit, was Anwendungsmöglichkeiten in Trennverfahren, Katalyse und Gasspeicherung eröffnen könnte. [source] A Rational Approach to the Ionothermal Synthesis of an AlPO4 Molecular Sieve with an LTA-Type Framework,ANGEWANDTE CHEMIE, Issue 27 2010Gesunde Struktur: Bei der Synthese eines AlPO4 -LTA-Zeoliths in ionischen Flüssigkeiten fungieren 1-Benzyl-3-methylimidazolium-, Tetramethylammonium- und Fluoridionen als Strukturbildner für die ,-Käfige, Sodalith-Käfige und würfelförmigen Baueinheiten (siehe Bild; C,grau, N,blau, O,rot, Al und P,pink, F grün). Selektives Entfernen der 1-Benzyl-3-methylimidazolium-Ionen ergab ein stabiles AlPO4 -LTA-Molekularsieb. [source] ChemInform Abstract: Double Michael Addition of Dithiols to Acetylenic Carbonyl Compounds under the Influence of Molecular Sieve and Dimethyl Sulfoxide.CHEMINFORM, Issue 17 2010Tomoko Kakinuma Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Molecular Sieve (MS 4A) Promoted Cyclocondensation of Hindered, Aromatic Nitrile Oxides and Cyclic Diketones under Mild Conditions.CHEMINFORM, Issue 2 2004Tomoo Matsuura Abstract For Abstract see ChemInform Abstract in Full Text. [source] Efficient Synthesis of ,-Glycosphingolipids by Reaction of Stannylceramides with Glycosyl Iodides Promoted by TBAI/AW 300 Molecular SievesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 2 2010José Antonio Morales-Serna No abstract is available for this article. [source] Efficient Synthesis of ,-Glycosphingolipids by Reaction of Stannylceramides with Glycosyl Iodides Promoted by TBAI/AW 300 Molecular SievesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 23 2009José Antonio Morales-Serna Abstract TBAI and acid-washed molecular sieves efficiently promoted the glycosylation of stannylceramides with glycosyl iodides. This direct glycosylation reaction reduces the overall number of synthetic steps and provides rapid access to ,-glycosphingolipids such as GalCer, ,-lactosylceramide, and iGB3 in good yield and with complete chemo- and stereoselectivity. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] ChemInform Abstract: Synthesis of Methyl 2-Methylazulene-3-carboxylate in the Presence of Molecular Sieves and Reaction with N-Bromosuccinimide.CHEMINFORM, Issue 31 2008Dao-Lin Wang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Preparation of Deuterium Labelled Organophosphonium Salts (Wittig Salts) under Hydrothermal Condition Catalyzed by Molecular Sieves.CHEMINFORM, Issue 49 2004Mitsuru Yamamoto Abstract For Abstract see ChemInform Abstract in Full Text. [source] Heterogeneous Catalytic Transfer Hydrogenation of Aromatic Nitro and Carbonyl Compounds over Cobalt(II) Substituted Hexagonal Mesoporous Aluminophosphate Molecular Sieves.CHEMINFORM, Issue 6 2003Susanta K. Mohapatra Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Critical Importance of Molecular Sieves in Titanium(IV),Calix[4]arene Catalyzed Epoxidation of Allylic Alcohols.CHEMINFORM, Issue 23 2001Antonio Massa Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Synthesis of Phenazine 5,10-Dioxides from Benzofuroxan Catalyzed by Molecular Sieves.CHEMINFORM, Issue 6 2001Tohru Takabatake Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Automated egg-collecting and pupa-separator system for medfly mass-rearing facilitiesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2008Ivan Morávek Abstract The new automated egg-collecting system and pupa-separator device described here substantially reduces labour during medfly [Ceratitis capitata (Wiedemann) (Diptera: Tephritidae)] mass production. The egg-collecting system gathers eggs dropping from the cage's oviposition net into a continuous stream of water, after which they accumulate in an egg-collecting sieve. The system provides an optimal environment for eggs, keeping them in a slow stream of well-oxygenated water. A pupa separator was designed to enable the separation of pupae from the pupation medium by sucking off the medium through a slowly moving sieving belt. The smaller particles of pupation medium are removed by a vacuum cleaner located under the circular sieving belt, and the pupae are collected in a collecting box. Quality control tests of the eggs collected and pupae separated have shown that neither system has a negative effect on the quality of the eggs or the pupae. [source] Towards a platform for the metabonomic profiling of different strains of Drosophila melanogaster using liquid chromatography,Fourier transform mass spectrometryFEBS JOURNAL, Issue 22 2009Muhammad A. Kamleh A platform based on hydrophilic interaction chromatography in combination with Fourier transform mass spectrometry was developed in order to carry out metabonomics of Drosophila melanogaster strains. The method was able to detect , 230 metabolites, mainly in the positive ion mode, after checking to eliminate false positives caused by isotope peaks, adducts and fragment ions. Two wild-type strains, Canton S and Oregon R, were studied, plus two mutant strains, Maroon Like and Chocolate. In order to observe the differential expression of metabolites, liquid chromatography-mass spectrometry analyses of the different strains were compared using sieve 1.2 software to extract metabolic differences. The output from sieve was searched against a metabolite database using an Excel-based macro written in-house. Metabolic differences were observed between the wild-type strains, and also between both Chocolate and Maroon Like compared with Oregon R. It was established that a metabonomic approach could produce results leading to the generation of new hypotheses. In addition, the structure of a new class of lipid with a histidine head group, found in all of the strains of flies, but lower in Maroon Like, was elucidated. [source] Magnetic Multi-Functional Nano Composites for Environmental ApplicationsADVANCED FUNCTIONAL MATERIALS, Issue 8 2009Jie Dong Abstract A novel concept is proposed to synthesize a new class of composites featuring magnetic, molecular sieve and metallic nanoparticle properties. These multi-functional materials have potential applications as recyclable catalysts, disinfectants and sorbents. The magnetic property enables effective separation of the spent composites from complex multiphase systems for regeneration and recycle, safe disposal of the waste and/or recovery of loaded valuable species. The zeolite molecular sieve provides a matrix which supports a remarkably new, simple, efficient and economical method to make stable, supported silver nanoparticles by silver ion exchange and controlled thermal reduction. The silver nanoparticles generated in this way have excellent properties such as high reactivity and good thermal stability without aggregation, which act as nano reactors for desired functionality in a wide range of applications. Magnetic component (Fe3O4), molecular sieve matrix (zeolite) and silver nanoparticles generated by ion exchange followed by controlled reduction, together form this unique novel composite with designed functions. It represents a practically operational, economical, sustainable and environmentally friendly new advanced functional material. This paper focuses on the novel synthesis and characterization of the composite, with an example of applications as sorbents for the removal of vapor-phase mercury from the flue gas of coal-fired power plants. [source] Hydrothermal Synthesis of Structure- and Shape-Controlled Manganese Oxide Octahedral Molecular Sieve NanomaterialsADVANCED FUNCTIONAL MATERIALS, Issue 9 2006W.-N. Li Abstract Highly uniform single-crystal Na-OMS-2 (OMS: octahedral molecular sieve), pyrolusite, and ,-MnO2 nanostructures with an interesting 3D urchinlike morphology have been successfully prepared using a hydrothermal method based on a mild and direct reaction between sodium dichromate and manganese sulfate. The crystal phases, shapes, and tunnel sizes of the manganese dioxide nanostructures can be tailored. Reaction temperature, concentrations of the reactants, and acidity of the solution play important roles in controlling the synthesis of these manganese dioxides. Field-emission scanning electron microscopy and transmission electron microscopy (TEM) studies show that the nanomaterials obtained are constructed of self-assembled nanorods. X-ray diffraction and TEM results indicate that the constituent manganese dioxide particles are single-crystalline materials. Energy dispersive X-ray analysis and magnetic studies imply that chromium cations may be incorporated into the framework and/or tunnels of the manganese dioxides. A mechanism for the growth of manganese dioxides with urchinlike architectures is proposed. [source] Direct Synthesis of Highly Stable Mesoporous Molecular Sieves Containing Zeolite Building Units,ADVANCED FUNCTIONAL MATERIALS, Issue 2 2005A. Sakthivel Abstract A novel, one-step synthesis of a highly stable mesoporous molecular sieve (MMS-H), which has a structure analogous to MCM-48 but which contains zeolite building units, is reported. A variety of experimental techniques,X-ray diffraction (XRD), N2 adsorption/desorption, transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, hyperpolarized 129Xe,NMR, and solid-state 27Al and 31P,magic-angle spinning (MAS) NMR spectroscopies,have been used to characterize the framework structure, porosity, and acidity of this novel mesoporous/microporous composite material, which is also found to possess superior thermal, hydrothermal, steam, and mechanical stabilities. [source] A convenient synthesis of oxazolidinone derivatives linezolid and eperezolid from (S)-glyceraldehyde acetonideHETEROATOM CHEMISTRY, Issue 3 2008Guangyu Xu A new convenient method for the synthesis of oxazolidinone antibacterials Linezolid and Eperezolid from readily available (S)-glyceraldehyde acetonide was developed. The key steps include reductive amination of arylamine and (S)-glyceraldehyde acetonide in the presence of NaBH4 and 4 Å sieve, followed by hydrolysis and regioselective cyclization. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:316,319, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20435 [source] Spatial patterns of benthic diversity: is there a latitudinal gradient along the Norwegian continental shelf?JOURNAL OF ANIMAL ECOLOGY, Issue 3 2002Karie. Summary 1We examined data on soft-sediment macrobenthos (organisms retained on a 1-mm sieve) from a transect of c. 1960 km along the Norwegian continental shelf (56,71°N), covering a range of water depths (65,434 m) and varying sediment properties. 2A total of 809 species was recorded from 101 sites. Of these, 36% were restricted to one or two sites, and 29% were represented by one or two individuals. No species spanned the entire transect. Polychaetes were the dominant taxonomic group, followed by crustaceans, molluscs and echinoderms. 3Alpha diversity (sample species richness) was highly variable (35,148 species) but showed no evidence of a relationship to latitude or other environmental variables. 4Beta diversity was measured as Whittaker's ,W, the number of shared species, complementarity (biotic distinctness) and Bray,Curtis similarity, and there was no evidence of a latitudinal trend on the shelf. Beta diversity increased with the level of environmental variability, and was highest in the southern-central area, followed by the most northern area. Change in environmental variables had a stronger effect on beta diversity than spatial distance between sites. 5Gamma diversity was computed by pooling samples over large areas. There was no convincing evidence of a latitudinal cline in gamma diversity, but gamma diversity increased with the level of environmental heterogeneity. Mean alpha diversity and gamma diversity were not significantly correlated. Whereas mean complementarity and mean Bray,Curtis similarity were related to gamma diversity, ,W was not. [source] Structure determination of diclofenac in a diclofenac-containing chitosan matrix using conventional X-ray powder diffraction dataJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 2 2004Nongnuj Muangsin The structure determination of diclofenac embedded in a diclofenac-containing chitosan matrix using conventional X-ray powder diffraction data is demonstrated. It reveals that sodium diclofenac, the starting material in the preparation of a controlled-release diclofenac-containing chitosan matrix, changes to diclofenac acid in space group C2/c in the matrix. Simple methods were employed for handling the sample to obtain X-ray powder diffraction data of sufficiently high quality for the determination of the crystal structure of diclofenac embedded in chitosan. These involved grinding and sieving several times through a micro-mesh sieve to obtain a suitable particle size and a uniformly spherical particle shape. A traditional technique for structure solution from X-ray powder diffraction data was applied. The X-ray diffraction intensities were extracted using Le Bail's method. The structure was solved by direct methods from the extracted powder data and refined using the Rietveld method. For comparison, the single-crystal structure of the same drug was also determined. The result shows that the crystal structure solved from conventional X-ray powder diffraction data is in good agreement with that of the single crystal. The deviations of the differences in bond lengths and angles are of the order of 0.030,Å and 0.639°, respectively. [source] Properties and application of poly(methacrylic acid- co -dodecyl methacrylate- cl - N,N -methylene bisacrylamide) hydrogel immobilized Bacillus cereus MTCC 8372 lipase for the synthesis of geranyl acetateJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2008Madan Lal Verma Abstract A range of fatty acid esters is now being produced commercially with immobilized microbial lipases (glycerol ester hydrolases; EC) in nonaqueous solvents. In this study, a synthetic hydrogel was prepared by the copolymerization of methacrylic acid and dodecyl methacrylate in the presence of a crosslinker, N,N -methylene bisacrylamide. A purified alkaline thermotolerant bacterial lipase from Bacilluscereus MTCC 8372 was immobilized on a poly(methacrylic acid- co -dodecyl methacrylate- cl - N,N -methylene bisacrylamide) hydrogel by an adsorption method. The hydrogel showed a 95% binding efficiency for the lipase. The bound lipase was evaluated for its hydrolytic potential toward various p -nitrophenyl acyl esters with various C chain lengths. The bound lipase showed optimal hydrolytic activity toward p -nitrophenyl palmitate at a pH of 8.5 and a temperature of 55°C. The hydrolytic activity of the hydrogel-bound lipase was enhanced by Hg2+, Fe3+, and NH ions at a concentration of 1 mM. The hydrogel-bound lipase was used to synthesize geranyl acetate from geraniol and acetic acid in n -heptane. The optimization of the reaction conditions, such as catalyst loading, effect of substrate concentration, solvent (n -pentane, n -hexane, n -heptane, n -octane, and n -nonane), reaction time, temperature, molecular sieve (3 Å × 1.5 mm) and scale up (at 50-mL level), was studied. The immobilized lipase (25 mg/mL) was used to perform an esterification in n -alkane(s) that resulted in the synthesis of approximately 82.8 mM geranyl acetate at 55°C in n -heptane under continuous shaking (160 rpm) after 15 h when geraniol and acetic acid were used in a ratio of 100 : 100 mM. The addition of a molecular sieve (3 Å × 1.5 mm) to the reaction system at a concentration of 40 mg/mL in reaction volume (2 mL) resulted in an increase in the conversion of reactants into geranyl acetate (90.0 mM). During the repetitive esterification under optimum conditions, the hydrogel-bound lipase produced ester (37.0 mM) after the eighth cycle of reuse. When the reaction volume was scaled up to 50 mL, the ester synthesized was 58.7 mM under optimized conditions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Properties of poly(AAc- co -HPMA- cl -EGDMA) hydrogel-bound lipase of Pseudomonas aeruginosa MTCC-4713 and its use in synthesis of methyl acrylateJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2007Shamsher Singh Kanwar Abstract Microbial lipases (E.C. 3.1.1.3) are preferred biocatalysts for the synthesis of esters in organic solvents. Various extracellular thermoalkaliphilic lipases have been reported from Pseudomonas sp. In the present study, a purified alkaline thermoalkalophilic extracellular lipase of Pseudomonas aeruginosa MTCC-4713 was efficiently immobilized onto a synthetic poly(AAc- co -HPMA- cl -EGDMA) hydrogel by adsorption and the bound lipase was evaluated for its hydrolytic potential towards various p -nitrophenyl acyl esters varying in their C-chain lengths. The bound lipase showed optimal hydrolytic activity towards p -nitrophenyl palmitate (p -NPP) at pH 8.5 and temperature 45°C. The hydrolytic activity of the hydrogel-bound lipase was markedly enhanced by the presence of Hg2+, Fe3+, and NH salt ions in that order. The hydrogel-immobilized lipase (25 mg) was used to perform esterification in various n -alkane(s) that resulted in , 84.9 mM of methyl acrylate at 45°C in n -heptane under shaking (120 rpm) after 6 h, when methanol and acrylic acid were used in a ratio of 100 mM:100 mM, respectively. Addition of a molecular sieve (3Å × 1.5 mm) to the reaction system at a concentration of 100 mg/reaction vol (1 mL) resulted in a moderate enhancement in conversion of reactants into methyl acrylate (85.6 mM). During the repetitive esterification under optimum conditions, the hydrogel-bound lipase produced 71.3 mM of ester after 10th cycle of reuse. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 183,191, 2007 [source] Reliable production of highly concentrated bioethanol by a conjunction of pervaporation using a silicone rubber sheet-covered silicalite membrane with adsorption processJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2004Toru Ikegami Abstract For the production of highly concentrated bioethanol by pervaporation using an ethanol-permselective silicalite membrane, pervaporation performance was investigated using a silicalite membrane entirely covered with a silicone rubber sheet to prevent direct contact with acidic compounds. By using a resistance model for membrane permeation, the separation factor of the covered silicalite membrane towards ethanol can be estimated from the individual pervaporation performances of the silicalite membrane and the silicone rubber sheet. No decrease in the ethanol concentration through the silicone rubber sheet-covered membrane was caused when ethanol solutions containing succinic acid were supplied. By directly passing the permeate-enriched ethanol vapor mixed with water vapor through a dehydration column packed with a molecular sieve of pore size 0.3 nm, highly concentrated bioethanol up to 97% (w/w), greater than the azeotropic point in the ethanol/water binary systems, can be obtained from 9% (w/w) fermentation broth. Copyright © 2004 Society of Chemical Industry [source] DEVELOPMENT OF A ROTARY PULVERIZER FOR CASSAVA CAKE IN GARI PRODUCTIONJOURNAL OF FOOD PROCESS ENGINEERING, Issue 6 2008L.A. SANNI ABSTRACT The use of a raffia sieve for pulverizing and sifting cassava cake during gari processing is slow, unhygienic and hazardous. A rotary brush and screen mechanism was developed for the pulverization of cassava cake with a view to eliminate the above-mentioned limitations of the existing methods. Machine performance was measured by comparing the product from the raffia sieve with that from a rotary sifter. The 5-mm screen aperture gave a gari of about the same bulk density with that of the raffia sieve. Although the throughput of the rotary sifter using a 5-mm sieve (227.71 kg/h) was lower than that of a 7-mm sieve (350 kg/h), the uniformity coefficient of 1.72 using the 5-mm sieve compared favorably with that of the raffia sieve. The pulverizing efficiency was higher (81.2%), with the 5-mm sieve than with the 7-mm sieve. The higher pulverizing efficiency of the machine reduces the drudgery associated with the pulverization of pressed cassava cake and improves productivity. PRACTICAL APPLICATIONS This research reduces the drudgery and hazard associated with the pulverization and sifting of cassava cake during gari processing in rural West Africa, where the bulk of the world's gari is being processed manually. [source] OCCURRENCE OF LISTERIA SPECIES IN THE PROCESSING STAGES OF FROZEN PEPPERJOURNAL OF FOOD SAFETY, Issue 2 2007SOLMAZ LEE ABSTRACT The occurrence of Listeria monocytogenes and other Listeria spp. in a frozen vegetable processing factory was investigated. From May to October 2002, four separate visits were made to the plant and during all of these visits, a total of 216 samples were collected at different stages of the cube and strip pepper processing line. Additionally, 28 swabs were taken from equipment and food-related contact surfaces. The cube and strip pepper processing lines include raw materials, washing, conveyor belt, scalding, cutting, sieving (drying), and the interior sieve of individually quick frozen (IQF), IQF and finished products. Swab samples were taken from the scalding tank, cooling tank, conveyor belt to IQF, interior part of IQF, mixing shovel of IQF, transport saddles and packaging materials. No Listeria spp. were isolated from the strip pepper processing stages, however, 26 out of 108 (24.1%) samples taken from the cube pepper processing stages were found to be contaminated with Listeria spp. Among these isolates, L. monocytogenes was not identified; however, Listeria welshimeri, Listeria innocua and Listeria ivanovii species were identified in 15, 6 and 5 of the tested samples, respectively. L. welshimeri and L. ivanovii were also isolated from three swab samples. These indicate that even though L. monocytogenes was not isolated, the presence of other Listeria species, particularly L. innocua, in the processing line would be an important criterion for eventual L. monocytogenes contaminations. Thus, periodic controls and application of general hygiene and sanitation principles are necessary in the prevention of possible contaminations. [source] Milk Protein Analysis Using a Micro Fabricated Sieve: A Promising PossibilityJOURNAL OF FOOD SCIENCE, Issue 3 2001C.S. Rao ABSTRACT: In cheese making, proteins present in the micellar phase, i.e., ,, ,, ,, , casein and their variants, determine the yield and properties of the final product (Walsh and others 1995). The current milk prices are based on solid components, that is, fat, total protein and other solids. However, the cheese yields are extremely sensitive to variations in protein sub-components. Thus, total protein content, although a simple measure of yield, is not the most accurate one. In the future, the food industry might require simple tools to analyze protein components in a given sample of milk. Two features of such a tool, portability and accuracy, would be invaluable. In this article, a protocol for design of a micro-scale sieve for the separation of proteins is conceived. [source] Location of Caspase 3-like Protease in the Development of Sieve Element and Tracheary Element of Stem in Cucurbita moschataJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 12 2008Xia Hao Abstract The casepase is considered to regulate the process of programmed cell death in the development of organisms. In this study, caspase 3-like protease was detected by immunohistochemistry and immunoelectron microscopy during the development of sieve element and tracheary element of stem in Cucurbita moschata Duch. Antibody with brown color (under light microscopy) and gold particles (under transmission electron microscopy) for detecting caspase 3-like protease was mainly displayed in inner phloem, external phloem and xylem in the region close to procambium. From the results it was considered that caspase 3-like protease did exist in vascular elements and played different roles during the development of sieve and tracheary elements, and different types of programmed cell death might be carried out. The caspase 3-like protease mainly participated in making cytoplasmic streaming cease and in degrading P-protein bodies; however, it rarely participated in the function for signal transferring in the developmental sieve element. However, it might induce calcium accumulation for rupturing the tonoplast in the signal of PCD in the developmental tracheary element. [source] Separation of mono- and dibranched hydrocarbons on silicaliteAICHE JOURNAL, Issue 9 2002E. Jolimaitre Breakthrough curves for mixtures of C5 and C6 hydrocarbons with different degrees of branching were obtained experimentally on a silicalite molecular sieve by fixed-bed experiments. The kinetic separation of di- from monobranched hydrocarbons was feasible on this type of zeolite: dimethyl molecules enter silicalite crystals very slowly, whereas monomethyl molecules are quickly adsorbed. Experimental results were compared to a theoretical isothermal model, considering the variation of diffusivity with concentration according to the Maxwell,Stefan theory. The parameters of the model (adsorption equilibria and diffusivities) were determined from single-component breakthrough curves. Experimental curves were generally well represented by the model, but the variation of diffusivity with concentration, as predicted by the Maxwell,Stefan theory, did not significantly improve the model prediction of experimental breakthrough curves by using a mean value of diffusivity. [source] | ||||||||||||||||||||||||||||||||||||||||