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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal of atmospheric chemistry 24 (1996), S. 211-239 
    ISSN: 1573-0662
    Keywords: air pollution ; field study ; modelling ; atmospheric chemistry ; troposphere ; clouds ; nitrogen compounds ; NO x ; NO3 ; N2O5 ; NO3 - ; NO2 - ; HNO3 ; HNO2
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Four case studies are described, from a three-site field experiment in October/November 1991 using the Great Dun Fell flow-through reactor hill cap cloud in rural Northern England. Measurements of total odd-nitrogen nitrogen oxides (NO y ) made on either side of the hill, before and after the air flowed through the cloud, showed that 10 to 50% of the NO y , called NO z , was neither NO nor NO2. This NO z failed to exhibit a diurnal variation and was often higher after passage through cloud than before. No evidence of conversion of NO z to NO3 - in cloud was found. A simple box model of gas-phase chemistry in air before it reached the cloud, including scavenging of NO3 and N2O5 by aerosol of surface area proportional to the NO2 mixing ratio, shows that NO3 and N2O5 may build up in the boundary layer by night only if stable stratification insulates the air from emissions of NO. This may explain the lack of evidence for N2O5 forming NO3 - in cloud under well-mixed conditions in 1991, in contrast with observations under stably stratified conditions during previous experiments when evidence of N2O5 was found. Inside the cloud, some variations in the calculated total atmospheric loading of HNO2 and the cloud liquid water content were related to each other. Also, indications of conversion of NO x to NO z were found. To explain these observations, scavenging of NO x and HNO2 by cloud droplets and/or aqueous-phase oxidation of NO2 - by nitrate radicals are considered. When cloud acidity was being produced by aqueous-phase oxidation of NO x or SO2, NO3 - which had entered the cloud as aerosol particles was liberated as HNO3 vapour. When no aqueous-phase production of acidity was occurring, the reverse, conversion of scavenged HNO3 to particulate NO3 -, was observed.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of atmospheric chemistry 29 (1998), S. 299-314 
    ISSN: 1573-0662
    Keywords: rate constant ; temperaturedependence ; troposphere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Accurate values for the rate and temperature dependence of the reaction NO + O3 → NO2 + O2 are important in the chemical modelling of photochemical processes in the atmosphere. Previous measurements have been made at low total pressures and/or with very large mixing ratios relative to those observed in the atmosphere. In this study the reaction rate has been measured using a novel approach under tropospheric conditions of temperature and pressure, and at tens of ppb (mixing ratios of 1 in 108) between 263 and 328 K. The resultant Arrhenius expression (k=Ae-Ea/RT) gives a larger activation energy (Ea/R=1670 ± 100) than the recommended literature value (Ea/R=1400 ± 200), and a larger pre-exponential factor (A=5.1 ± 1.6 × 10-12 cf. recommended A=2.0 × 10-12), but the second-order rate constant at 298 K (1.90 × 10-14 molecules cm-3 s-1 ± 10%) is similar to the recommended value. The results confirm a lack of pressure dependence of the reaction, but were made over too small a range in temperature to address the issue of curvature of the simple Arrhenius expression.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of the American Chemical Society 81 (1959), S. 3151-3152 
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 50 (1985), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Restructured beef products (18 – 20% fat) were formulated and pasteurized to provide storage stability at 4.4°C. An optimal formulation was determined with a full factorial experiment having 4 levels of whey and rennet-treated sodium caseinate blend and 3 levels of texturized soy protein. Response surfaces for product yield, fat retention and bind strength were calculated utilizing regression procedures. Maximum product yield of 92% was predicted by the optimization and subsequently achieved. An observed fat retention of 92% was lower than the predicted value. Over 16 wk of storage at 4.4°C, no aerobic or anaerobic bacterial growth was observed and TBA values remained very low.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 39 (1974), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 56 (1991), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Sodium lactate was added to fresh pork sausage to determine its effect on refrigerated storage of chubs and retail display of patties. An additional treatment evaluated effects of sodium lactate in fresh sausage with added textured soy concentrate. In fresh sausage stored as 454g chubs, surface discoloration was reduced (P〈0.01) and off-odor development abated (P〈0.01) with addition of sodium lactate. The lag phase of microbial growth was extended from 10 to 20 days with sodium lactate. Under retail conditions, sodium lactate did not affect lean color (P〉0.01) but resulted in more rapid surface discoloration (P〈0.01). Presence of textured soy concentrate decreased (P〈0.01) effectiveness of sodium lactate against microorganisms.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 51 (1986), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The effects of electrical stimulation, kidney fat removal time, tenderloin removal time, and storage and packaging treatment on tenderness and retail display characteristics of beef tenderloin steaks were studied. Electrical stimulation increased overall desirability scores on days 2 through 4 of retail display. Steaks from sides that had kidney and pelvic fat removed prior to chilling had higher Warner-Bratzler shear force values, darker muscle color and higher retail evaluations for overall desirability on days 2 through 4 of display than did steaks from conventionally dressed sides. Tenderloin steaks that were vacuum packaged and stored 14 days had higher bacterial counts, more uniform lean color and less visual purge in the retail package than did steaks retail displayed immediately after tenderloin removal.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 43 (1978), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Effects of a calcium alginate coating on retail beef pieces and steaks were studied. Microbiological analyses were performed on beef pieces following treatments with: (1) a calcium alginate coating; (2) a 200 ppm HOCl solution; (3) a combination of 1 and 2; (4) a coliform inoculation and/or (5) no treatment (control). Each sample was wrapped in a polyvinyl chloride (PVC) film and stored at 5°C for up to 7 days. The rate of microbial growth for total and coliform counts on the meat was not significantly different with coated and uncoated meat samples. The HOCl treated meat had significantly lower total microbial counts and coliform populations when compared to either the calcium alginate or the HOCl-calcium alginate treated meat. Acceptance of the calcium alginate film involved retail display and organoleptic evaluations of 40 2.54 cm thick beef steaks. Steaks that received the calcium alginate coating were significantly lower in shrinkage loss, drip and degree of off-odor detected through 96 hr storage when compared to the uncoated steaks. The coating significantly prolonged muscle color through 96 hr storage. No significant differences were observed between treatments for appearance, surface discoloration, flavor, juiciness, tenderness, overall acceptability or cooking loss.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    ISSN: 1365-2036
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background : Ciprofloxacin is effective in perianal Crohn's disease but after treatment discontinuation symptoms reoccur. Infliximab is effective but requires maintenance therapy.Aim : To evaluate the effect of combined ciprofloxacin and infliximab in perianal Crohn's disease.Methods : A double-blind placebo-controlled study was conducted. Patients were randomly assigned to receive 500-mg ciprofloxacin twice daily or a placebo for 12 weeks. All patients received 5-mg/kg infliximab in week 6, 8 and 12 and were followed for 18 weeks. Primary end-point was clinical response, defined as a 50% or greater reduction from baseline in the number of draining fistulae. Secondary end-points were the change in Perianal Disease Activity Index and hydrogen peroxide enhanced three-dimensional endoanal ultrasonography findings. Analysis was by intention-to-treat.Results : Twenty-four patients were included but two discontinued treatment. At week 18, response was 73% (eight of 11) in the ciprofloxacin group and 39% (five of 13) in the placebo group (P = 0.12). Using logistic regression analysis patients treated with ciprofloxacin tended to respond better (OR = 2.37, CI: 0.94–5.98, P = 0.07). The Perianal Disease Activity Index score only improved (P = 0.008) in the ciprofloxacin group. Three-dimensional endoanal ultrasonography improved in three patients with a clinical response.Conclusions : A combination of ciprofloxacin and infliximab tended to be more effective than infliximab alone.
    Type of Medium: Electronic Resource
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