scholarly journals Chemical Composition and Variation in Mean Values of Selected Crop Residues Fermented with Local Alkali Sources and Rumen Filtrate

2016 ◽  
Vol 46 (6) ◽  
pp. 35-44
Keyword(s):  
Chemical Composition ◽  
Crop Residues ◽  
Mean Values

A Statistical Investigation on Particle to Particle Variation of Fly Ash Using SEM-AIA-EDAX Technique.

1989 ◽  
Vol 178 ◽  
Author(s):  
L. E. Barta ◽  
G. VÁmos ◽  
M. A. Toqan ◽  
J. D. Teare ◽  
J. M. BeÉr ◽  
...  
Keyword(s):  
Fly Ash ◽  
Chemical Composition ◽  
Random Variables ◽  
Statistical Investigation ◽  
Distribution Functions ◽  
Mineral Matter ◽  
Size Distributions ◽  
Bulk Analysis ◽  
Mean Values ◽  
Particle Properties

AbstractDue to the particle to particle variation of coal mineral properties and random coalescence of mineral particles during coal burnout, fly ash particle properties change from particle to particle. The variations of particle properties (e.g. SiO2 content, viscosity) can be mathematically described by random variables. Since bulk analysis of fly ash gives only the mean values of chosen random variables, it is considered insufficient to describe the fly ash behavior either in boiler slagging/fouling or in different concrete structures. SEM-AIA-EDAX technique was used to supply raw data for estimating the distribution functions of particle size and chemical compounds in Texas lignite minerals and fly ash and Eagle Butte fly ash. To determine the volume based size distributions of these samples from their area-based size distributions, Abelian transformation was used. To estimate the distribution functions of CaO and SiO2 contents of the samples, particle area fractions were used. The confidence limits were also calculated for the estimated parameters. By determining the distribution functions of particle viscosity and chemical composition, it was shown that in the case of Texas lignite the coal burnout does not cause significant changes in the mineral matter properties. It was observed that the properties of fly ash depended solely on the mineral matter properties. However, in the Eagle Butte case the coal burnout has a major effect on the fly ash size distribution and its chemical composition.

scholarly journals Survey on the chemical composition of several tropical wood species

2019 ◽  
Vol 342 ◽  
Author(s):  
Jean Gérard ◽  
Sébastien Paradis ◽  
Bernard Thibaut
Keyword(s):  
Chemical Composition ◽  
Lignin Content ◽  
Silica Content ◽  
Ash Content ◽  
Hot Water ◽  
Mean Values ◽  
High Silica Content ◽  
Distribution Of Values ◽  
High Silica ◽  
Very High

Variability in the chemical composition of 614 species is described in a database containing measurements of wood polymers (cellulose, lignin and pentosan), as well as overall extraneous components (ethanol-benzene, or hot water extracts and ash, with a focus on silica content). These measurements were taken between 1945 and 1990 using the same standard protocol. In all, 1,194 trees belonging to 614 species, 358 genera and 89 families were measured. At species level, variability (quantified by the coefficient of variation) was rather high for density (27%), much lower for lignin and cellulose (14% and 10%) and much higher for ethanol/benzene extractives, hot water extractives and ash content (81%, 60% and 76%). Considering trees with at least five different specimens, and species with at least 10 different trees, it was possible to investigate within-tree and within-species variability. Large differences were found between trees of a given species for extraneous components, and more than one tree should be needed per species. For density, lignin, pentosan and cellulose, the distribution of values was nearly symmetrical, with mean values of 720 kg/m3 for density, 29.1% for lignin, 15.8% for pentosan, and 42.4% for cellulose. There were clear differences between species for lignin content. For extraneous components, the distribution was very dissymmetrical, with a minority of woods rich in this component composing the high value tail. A high value for any extraneous component, even in only one tree, is sufficient to classify the species in respect of that component. Siliceous woods identified by silica bodies in anatomy have a very high silica content and only those species deserve a silica study.

scholarly journals Modelling the impacts of iodine chemistry on the northern Indian Ocean marine boundary layer

2021 ◽  
Vol 21 (11) ◽  
pp. 8437-8454
Author(s):  
Anoop S. Mahajan ◽  
Qinyi Li ◽  
Swaleha Inamdar ◽  
Kirpa Ram ◽  
Alba Badia ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Chemical Composition ◽  
Indian Ocean ◽  
Marine Boundary Layer ◽  
Indian Subcontinent ◽  
Winter Period ◽  
Monsoon Period ◽  
Mean Values ◽  
Iodine Chemistry ◽  
Inorganic Iodine

Abstract. Recent observations have shown the ubiquitous presence of iodine oxide (IO) in the Indian Ocean marine boundary layer (MBL). In this study, we use the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem version 3.7.1), including halogen (Br, Cl, and I) sources and chemistry, to quantify the impacts of the observed levels of iodine on the chemical composition of the MBL. The model results show that emissions of inorganic iodine species resulting from the deposition of ozone (O3) on the sea surface are needed to reproduce the observed levels of IO, although the current parameterizations overestimate the atmospheric concentrations. After reducing the inorganic emissions by 40 %, a reasonable match with cruise-based observations is found, with the model predicting values between 0.1 and 1.2 pptv across the model domain MBL. A strong seasonal variation is also observed, with lower iodine concentrations predicted during the monsoon period, when clean oceanic air advects towards the Indian subcontinent, and higher iodine concentrations predicted during the winter period, when polluted air from the Indian subcontinent increases the ozone concentrations in the remote MBL. The results show that significant changes are caused by the inclusion of iodine chemistry, with iodine-catalysed reactions leading to regional changes of up to 25 % in O3, 50 % in nitrogen oxides (NO and NO2), 15 % in hydroxyl radicals (OH), 25 % in hydroperoxyl radicals (HO2), and up to a 50 % change in the nitrate radical (NO3), with lower mean values across the domain. Most of the large relative changes are observed in the open-ocean MBL, although iodine chemistry also affects the chemical composition in the coastal environment and over the Indian subcontinent. These results show the importance of including iodine chemistry in modelling the atmosphere in this region.

Yogurt — A Compositional Survey in the Greater Lansing Area1

1979 ◽  
Vol 42 (5) ◽  
pp. 424-426 ◽  
Author(s):  
M. L. RICHMOND ◽  
R. C. CHANDAN ◽  
C. M. STINE
Keyword(s):  
Standard Deviation ◽  
Chemical Composition ◽  
Product Category ◽  
Low Fat ◽  
Mean Values ◽  
Total Solids ◽  
Composition Control

Prompted by numerous consumer inquiries and several reports in the literature, this survey was undertaken to monitor the composition of yogurt in the mid-Michigan market. Forty-seven samples representing six brands were analyzed. Mean values ± standard deviation for the content of protein (Kjeldahl), fat (Mojonnier) and total solids (Mojonnier), pH and net weights were measured. The data are presented by product category, i.e. low-fat flavored, low-fat plain, full-fat flavored, full-fat plain, and cumulated for all samples. Wide variations in chemical composition were observed between and within brands surveyed. Mean values for all flavored samples surveyed (N = 42) were 4.34% protein, 2.34% fat, 25.88% total solids and 4.01 pH. Corresponding values for all plain samples surveyed were 5.68, 2.86, 16.90 and 4.23, respectively. The data show that 25% of all samples analyzed were greater than 6.6% overweight while 10.6% of the yogurts surveyed weighed less than the declared container net weight. Caloric values for flavored yogurts ranged widely. Mean caloric values for flavored, low-fat and full-fat brands were 106 and 121 cal/100 g, respectively. In general, the results indicate that commercial yogurt would benefit from closer composition control.

scholarly journals Praćenje mikrobiološke kvalitete i promjena kemijskog sastava mlijeka kobila primjenom različitih analitičkih metoda

2019 ◽  
Vol 69 (2) ◽  
pp. 138-146
Author(s):  
Ana Končurat ◽  
Lidija Kozačinski ◽  
Miroslav Benić ◽  
Marija Sedak ◽  
Tomislav Sukalić ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Milk Fat ◽  
Microbiological Quality ◽  
Bacterial Count ◽  
Total Bacterial Count ◽  
Lactation Period ◽  
Ir Spectrometry ◽  
Mean Values ◽  
Instrumental Methods ◽  
Coagulase Positive Staphylococci

In this study the quality of Croatian coldblooded mare’s milk during six months lactation period was investigated. Samples of milk were collected throughout six month’s lactation, from 22 mares and included three consecutive lactations. Physicochemical properties (pH, °SH, density) and chemical composition of raw mare milk have been studied. Fat, lactose, protein and solid non fat contents were analysed by infrared spectrophotometry and by conventional methods. Somatic cell count and microbiological parametres such as the total bacterial count, Enterobacteriaceae, coagulase positive staphylococci as well as presence of pathogens, Salmonella species and Listeria monocytogenes were also researched. Results are presented as comparison of standard and instrumental methods for chemical analysis (fat, protein, solid non fat, lactose). The mean values are presented as trends during lactation. Results were analysed by Stata 10.0. For results obtained by using different methods there were significant differences between methods for milk fat on 10th day, lactose content on 10th and 60th day, and total solids non fat on 60th day of lactation. Values of milk fat, protein, lactose and solids non fat obtained on the 40th, 60th, 120th and 180th days of lactation by IR spectrometry were compared with the value obtained on the 10th day of lactation by the same method (IR spectrometry). Milk of the Croatian coldblooded mares showed stabile chemical composition for all ingredients except lactose (p=0.0001), and high microbiological quality throughout the lactation period.

Assessing the Effect of Co-composting Technique to Generate Quality Manure Out of Water Hyacinth (Eichhornia crassipes)

2017 ◽  
Vol 104 (4 - 6) ◽  
Author(s):  
Prithiv Raj V ◽  
◽  
Ilakiya T ◽  
Nivedha P ◽  
Shahaya Sharmila A ◽  
...  
Keyword(s):  
Water Hyacinth ◽  
Eichhornia Crassipes ◽  
Crop Residues ◽  
Germination Percentage ◽  
Cow Dung ◽  
Aquatic Weed ◽  
Fungal Culture ◽  
Organic Substrates ◽  
Total N ◽  
Mean Values

An experiment was conducted during 2016-2017 to assess the efficacy of co-composting technique for generating quality manure out of the noxious aquatic weed, water hyacinth (Eichhornia crassipes). Locally available organic substrates viz., crop residues and cow dung were mixed with water hyacinth and co-inoculated with the fungal culture, Pleurotus djamor @ 0.05% and the earth worm, Eudrillus eugineae @ 0.2%. The treatment encompassing water hyacinth + crop residue + cow dung (1:1:1) along with P. djamor and E.eugineae showed higher mean values of total “N” (0.93%), “P” (1.00%), “K” (1.10%) content of manure, germination percentage (100 % each) and vigour index of 13.90 and 12.85, respectively for cluster bean and tomato ; whereas, water hyacinth + crop residues (1:1) without the bio-inoculants recorded higher mean total organic carbon of 40.85 %.

scholarly journals Infrared or ultrasonic milk analysis can affect its results?

2019 ◽  
Vol 49 (7) ◽  
Author(s):  
Guilherme Augusto Manske ◽  
Elisandra Rigo ◽  
Fábio José Gomes ◽  
Ana Luiza Bachmann Schogor
Keyword(s):  
Chemical Composition ◽  
Low Cost ◽  
Raw Milk ◽  
Physicochemical Analysis ◽  
Milk Analysis ◽  
Ultrasonic Spectroscopy ◽  
Mean Values ◽  
Brazilian Legislation ◽  
Standard Procedures ◽  
Significant Difference

ABSTRACT: Constant monitoring of milk quality by the processing industries demands the use of methodologies that add agility and low-cost analysis, such as the use of electronic equipment based on infrared or ultrasonic spectroscopy. In the present study, quality of raw milk received by dairy farms from western region of Santa Catarina state, Brazil, was evaluated throughout two methodologies of analysis of chemical composition and compared, being that both equipment used standard procedures for calibration, considering as reference data from the classic analytical methods recommended in Brazilian legislation. Milk samples from 45 producers were analyzed for SCC, TBC and physicochemical analysis, performed at dairy’s laboratory and at the official laboratory. Infrared and ultrasound methodologies for chemical composition of fat, protein and lactose were compared and correlated. The comparison of the methods showed that there was no significant difference for the mean values of fat (P=0.06); however, they presented significant difference for protein (P=0.001), higher for IR (3.23 vs. 3.33), and lactose (P<0.0001), higher for US (4.47 vs. 4.83). Correlation was positive and significant for fat (r=0.73, P<0.0001), protein (r=0.47, P=0.001) and lactose (r=0.51, P=0.0003). Considering the minimal composition required, TBC and SCC levels, 95.5%, 84.1% and 64.4% of the milk producers met the current Brazilian legislation, respectively. It was concluded that the methodologies have affected results, which may have been influenced by the correction factor used for equipment calibration, specifically for analyzed samples during the study period.

The Study of the Complex Mechanical Properties of Rolled Bars of VT6 Alloy as a Function of Chemical Composition and Structure Type

2020 ◽  
Vol 989 ◽  
pp. 283-289
Author(s):  
Yu.B. Egorova ◽  
L.V. Davydenko ◽  
I.M. Mamonov
Keyword(s):  
Mechanical Properties ◽  
Chemical Composition ◽  
Statistical Tests ◽  
Structure Type ◽  
Strength Properties ◽  
Alloying Elements ◽  
Mean Values ◽  
Composition And Structure ◽  
Composition Structure ◽  
The Stability

This paper presents the results of statistical tests, carried out to identify the mechanical properties of Ø 16-150 mm VT6 titanium alloy bars, as a function of their post-annealing chemical composition and structure. It is shown that the high variation of mechanical properties may be, due to fluctuations in the grade composition and structure type. 50% to 60% of variations in strength properties are due to composition + structure co-effects. To improve the stability of such properties, the paper identifies maximum permissible total fluctuations in the chemical composition in terms of aluminum/molybdenum equivalents of alloying elements and impurities. The research team has fitted the regression dependencies for evaluating the mean values of the mechanical properties of Ø 16-60 mm VT6 bars, as a function of the structure type and aluminum/molybdenum equivalents of the alloying elements and impurities.

EFFECT OF SULPHUR DIOXIDE AND AMMONIA ON CHEMICAL COMPOSITION AND IN VITRO DIGESTIBILITY OF CORN STOVER AND BARLEY STRAW

1989 ◽  
Vol 69 (4) ◽  
pp. 963-972 ◽  
Author(s):  
E. INNOCENTI ◽  
D. N. MOWAT ◽  
I. B. MANDELL
Keyword(s):  
Chemical Composition ◽  
Corn Stover ◽  
Sulphur Dioxide ◽  
Crop Residues ◽  
Treatment Time ◽  
Lignin Content ◽  
Temperature Treatment ◽  
Barley Straw ◽  
In Vitro Digestibility

The effects of temperature, treatment time and levels of SO2 and NH3 on the in vitro digestibility and chemical composition of corn stover and barley straw were evaluated. Sulphur dioxide improved (P > 0.05) in vitro dry matter digestibility (IVDMD) and in vitro cell wall digestibility (IVCWD) of corn stover when treated at 70 °C for 24 h. However, high SO2 levels (4 and 6%) at higher temperature (90 °C) and for a longer time (72 h) reduced (P < 0.05) IVDMD and IVCWD and increased (P < 0.05) lignin content. When barley straw was treated with SO2 at 70 °C, IVDMD and IVCWD were greater (P < 0.05) when the treatment was carried out for 72 h than for 24 h. The improvement in in vitro digestibilities with SO2 was associated with solubilization of large amounts of hemicellulose. Ammonia treatment at 70 °C for 24 h reduced (P < 0.05) hemicellulose content and increased (P < 0.05) IVDMD and IVCWD as well as apparent lignin content. Suphuration enhanced the effect of ammoniation on IVDMD and IVCWD and reduced lignin content, but did not further reduce hemicellulose over NH3 alone in both crop residues. Improvements in in vitro digestibilities obtained with NH3 treatment followed by SO2 were associated with reductions of hemicellulose and lignin. Sulphur dioxide and NH3 treatment at 70 °C for 24 h produced a greater improvement in IVDMD and IVCWD in barley straw than in corn stover. Treatment with SO2 following ammoniation further increased (P < 0.05) NH3-N and sulphur contents of corn stover. Key words: Chemical treatment, sulphur dioxide, ammonia, corn stover, barley straw, chemical composition, in vitro digestibility

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