RATIONALE FOR THE NECESSITY OF JOINT USE OF SAMPLE WEIGHT AND BATCH COMPOSITION VARIATION METHODS IN ROUTINE ASSAY ANALYSIS

Author(s):  
V.A. Shvetsov ◽  
◽  
V.P. Chicheva ◽  
O.A. Belavina ◽  
◽  
...  
2018 ◽  
Vol 9 (2) ◽  
pp. 67-73
Author(s):  
M Zainul Arifin

This research was conducted to determine the value of the highest compressive strength from the ratio of normal concrete to normal concrete plus additive types of Sika Cim with a composition variation of 0.25%, 0.50%, 0.75%, 1.00%, 1.25%, 1 , 50% and 1.75% of the weight of cement besides that in this study also aims to find the highest tensile strength from the ratio of normal concrete to normal concrete in the mixture of sika cim composition at the highest compressive strength above and after that added fiber wire with a size diameter of 1 mm in length 100 mm with a ratio of 1% of material weight. The concrete mix plan was calculated using the ASTM method, the matrial composition of the normal concrete mixture as follows, 314 kg / m3 cement, 789 kg / m3 sand, 1125 kg / m3 gravel and 189 liters / m3 of water at 10 cm slump, then normal concrete added variations of the composition of sika cim 0.25%, 0.50%, 0.75%, 1.00%, 1.25%, 1.5%, 1.75% by weight of cement and fiber, the tests carried out were compressive strength of concrete and tensile strength of concrete, normal maintenance is soaked in fresh water for 28 days at 30oC. From the test results it was found that the normal concrete compressive strength at the age of 28 days was fc1 30 Mpa, the variation in the addition of the sika cim additive type mineral was achieved in composition 0.75% of the cement weight of fc1 40.2 Mpa 30C. Besides that the tensile strength test results were 28 days old with the addition of 1% fiber wire mineral to the weight of the material at a curing temperature of 30oC of 7.5%.


1963 ◽  
Vol 44 (1) ◽  
pp. 47-66 ◽  
Author(s):  
W. Nocke ◽  
H. Breuer

ABSTRACT A method for the chemical determination of 16-epi-oestriol in the urine of nonpregnant women with a qualitative sensitivity of less than 0.5 μg/24 h is described. The separation of 16-epi-oestriol and oestriol is accomplished by converting 16-epi-oestriol into its acetonide, a reaction which is stereoselective for cis-glycols and therefore not undergone by oestriol as a trans-glycol. Following partition between chloroform and aqueous alkali, the acetonide of 16-epi-oestriol is completely separated with the organic layer whereas oestriol as a strong phenol remains in the alkaline phase. 16-epi-oestriol is chromatographed on alumina as the acetonide and determined as a Kober chromogen. This procedure can easily be incorporated into the method of Brown et al. (1957 b) thus making possible the simultaneous routine assay of oestradiol-17β, oestrone, oestriol and 16-epi-oestriol from one sample of urine. The specificity of the method was established by separation of 16-epi-oestriol from nonpregnancy urine as the acetonide, hydrolysis of the acetonide by phosphoric acid, isolation of the free compound by microsublimation and identification by micro melting point, colour reactions and chromatography. The accuracy of the method is given by a mean recovery of 64% for pure crystalline 16-epi-oestriol when added to hydrolysed urine in 5–10 μg amounts. The precision is given by s = 0.24 μg/24 h. For the duplicate determination of 16-epi-oestriol the qualitative sensitivity is 0.44 μg/24 h, the maximum percentage error being ± 100% The quantitative sensitivity (±25% error) is 1.7 μg/24 h.


2020 ◽  
Vol 16 ◽  
Author(s):  
Wan Haslindawani Wan Mahmood ◽  
Md Asiful Islam ◽  
Mimi Azreen Abdullah ◽  
Noor Haslina Mohd Noor ◽  
Indhira Subbiah ◽  
...  

Background: Prevalence and the risk of common antiphospholipid antibodies (aPLs) such as lupus anticoagulant (LA), anticardiolipin (aCL) and anti-β2-glycoprotein I (β2-GPI) antibodies in preeclampsia is a matter of debate. Recently, interests have expanded in evaluating the risks of presenting non-classic aPLs in preeclampsia patients. Objective: The objective of this case-control study was to evaluate some haematological parameters besides assessing the presence of anti-annexin A5 and antiphosphatidylinositol (aPI) antibodies in preeclampsia patients compared to nonpreeclampsia subjects. Methods: From two hospitals in Malaysia, a total of 84 subjects were recruited in this case-control study including 42 preeclampsia and 42 age-matched non-preeclampsia subjects. Some haematological parameters [i.e., haemoglobin, total white blood cell, platelet, prothrombin time and activated partial thromboplastin time (APTT)] were assessed besides screening for anti-annexin A5 and aPI antibodies. Results: Among the haematological parameters, APTT was significantly high in mild preeclampsia when compared to severe preeclampsia subjects (p=0.007). IgG anti-annexin A5 antibody was detected in a single preeclampsia subject only (2.4%) and none in non-preeclampsia subjects. Conclusion: Because of the low prevalence, non-classic aPLs should not be considered as a risk factor in developing preeclampsia and not justifiable to consider as a routine assay in pregnant women.


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4565
Author(s):  
Sergiu Pădureţ

The textural properties of butter are influenced by its fat content and implicitly by the fatty acids composition. The impact of butter’s chemical composition variation was studied in accordance with texture and color properties. From 37 fatty acids examined, only 18 were quantified in the analyzed butter fat samples, and approximately 69.120% were saturated, 25.482% were monounsaturated, and 5.301% were polyunsaturated. The butter samples’ viscosity ranged between 0.24 and 2.12 N, while the adhesiveness ranged between 0.286 to 18.19 N·mm. The principal component analysis (PCA) separated the butter samples based on texture parameters, fatty acids concentration, and fat content, which were in contrast with water content. Of the measured color parameters, the yellowness b* color parameter is a relevant indicator that differentiated the analyzed sample into seven statistical groups; the ANOVA statistics highlighted this difference at a level of p < 0.001.


Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2225
Author(s):  
Aleksandra Kotarska ◽  
Tomasz Poloczek ◽  
Damian Janicki

The article presents research in the field of laser cladding of metal-matrix composite (MMC) coatings. Nickel-based superalloys show attractive properties including high tensile strength, fatigue resistance, high-temperature corrosion resistance and toughness, which makes them widely used in the industry. Due to the insufficient wear resistance of nickel-based superalloys, many scientists are investigating the possibility of producing nickel-based superalloys matrix composites. For this study, the powder mixtures of Inconel 625 superalloy with 10, 20 and 40 vol.% of TiC particles were used to produce MMC coatings by laser cladding. The titanium carbides were chosen as reinforcing material due to high thermal stability and hardness. The multi-run coatings were tested using penetrant testing, macroscopic and microscopic observations, microhardness measurements and solid particle erosive test according to ASTM G76-04 standard. The TiC particles partially dissolved in the structure during the laser cladding process, which resulted in titanium and carbon enrichment of the matrix and the occurrence of precipitates formation in the structure. The process parameters and coatings chemical composition variation had an influence on coatings average hardness and erosion rates.


Author(s):  
Anastasia Chrysovalantou Chatziioannou ◽  
Eric Benjamins ◽  
Linette Pellis ◽  
Alfred Haandrikman ◽  
Lubbert Dijkhuizen ◽  
...  

1991 ◽  
Vol 71 (2) ◽  
pp. 469-480 ◽  
Author(s):  
J. M. Bell ◽  
M. O. Keith

Canola samples of whole seed, press cake and commercial meal (CM) were collected from seven canola-crushing plants in Western Canada over 4 successive weeks to assess nutrient and glucosinolate content and variability. The CM data are described in this report. The mean concentrations in CM (dry matter (DM) basis) were: in %, crude protein (N × 6.25) 41.85; ether extract 3.92; crude fiber 13.13; neutral detergent fiber 23.54; acid detergent fiber 19.09; and in MJ kg−1, gross energy 20.36. The mean mineral concentrations were, in percent, calcium 0.70; magnesium 0.57; phosphorus 1.13; potassium 1.35; sulfur 0.94; and in μg g−1, copper 6.34; iron 157; manganese 54.7; molybdenum 1.5; selenium 1.22; zinc 75.8. Total aliphatic glucosinolate concentrations (oil-free DM basis) ranged from 6.26 to 28.42 μmol g−1 for different plants, mean 16.20; indolyl glucosinolate concentrations were from 0.56 to 9.49 μmol g−1. Small and variable amounts of allyl and hydroxybenzyl glucosinolates due to weed seed contamination were found. Myrosinase activity (thioglucoside glucohydrolase EC 3.2.3.1) averaged 0.15% of that in the corresponding canola seed. Differences among crushing plants were due mainly to regional environmental factors, cultivars used and, for lysine and glucosinolates, processing conditions mainly in the desolventizer toaster stage. Key words: Canola, meal, composition, variation, regional, Western Canada


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