Vario el 2

Manufactured by Elementar

Sourced in Germany

The Vario EL II is an elemental analyzer that determines the content of carbon, hydrogen, nitrogen, and sulfur in a wide range of solid and liquid samples. It operates based on the principle of high-temperature combustion and provides rapid and precise elemental analysis.

Automatically generated - may contain errors

Lab products found in correlation

Vario max, by Elementar (1 mentions) Sulphanilic acid, by Merck Group (1 mentions) Sulfuric acid, by Carl Roth (1 mentions) Vario max cn, by Elementar (1 mentions) Vario toc cube, by Elementar (1 mentions)

Spelling variants of this product

Vario EL (64 citations)

6 protocols using vario el 2

Assessing Biochar Carbon Stability

Check if the same lab product or an alternative is used in the 5 most similar protocols

Two methods (H₂O₂ and K₂Cr₂O₇ oxidation treatments) were used to assess the chemical stability of C in biochar according to the method described by a previous study [11 (link)]. Briefly, a certain amount of biochar containing 0.10 g C was put into a glass test tube, and then, 7 mL of 5% H₂O₂ or 40 mL of 0.1 M K₂Cr₂O₇/2 M H₂SO₄ solution was added. These glass test tubes were heated in an air oven and held at 80 °C for 48 h and at 55 °C for 60 h. After oxidation, the samples were washed with deionized water. The weight of residue was recorded after oven-drying at 105 °C for 6 h, and its C content was also determined using an elemental analyzer (Vario ELII, Elementar, Hanau, Germany). The chemical stability of C was expressed as the remaining ratio of C after chemical oxidation.

where W_i and W_f are the weights (g) of sample before and after oxidation treatment, respectively; C_i and C_f are the initial and final C contents (%) of the sample, respectively.
The TGA of biochar in N₂ and air atmosphere was used to assess the thermal and oxidation stability, respectively, in which the biochar was heated from room temperature to 800 °C at 10 °C per min.

Bai T., Ma W., Li W., Jiang J., Chen J., Cao R., Yang W., Dong D., Liu T, & Xu Y. (2023). Effect of Different Phosphates on Pyrolysis Temperature-Dependent Carbon Sequestration and Phosphorus Release Performance in Biochar. Molecules, 28(9), 3950.

+ Open protocol

+ Expand

Soil Sampling and Characterization Protocol

Check if the same lab product or an alternative is used in the 5 most similar protocols

Soil samples were stored at 4°C prior to processing. Coarse stones of a diameter >4 mm and roots of a diameter >1 mm were removed from the samples prior to drying at 40°C. Stone and root samples were air-dried separately. Then, soil samples were sieved to <2 mm. Particles >2 mm were combined with the coarse stones. Dry weights of roots and combined stone fractions were determined. Total C and N concentrations in <2 mm soil separates were determined using dry combustion at 1100°C (VarioMax, Elementar Analysensysteme GmbH, Hanau, Germany). Carbonate C was determined after dry combustion of the samples heated in a muffle furnace at 450°C for 16 h. Organic C was calculated as the difference between total and carbonate C. Litter layer samples were dried at 70°C, shredded, and a subsample further homogenized using a ball mill. Total C and N concentrations were determined using dry combustion (Vario EL II, Elementar Analysensysteme GmbH, Hanau, Germany). Nitrogen concentrations reflect total (organic plus inorganic) N (TN). Bulk density was determined based on the dry mass of total soil material of each depth increment. Accordingly, bulk density, fine earth material (<2 mm), and OC concentrations were measured on the same samples.

Schrumpf M., Kaiser K, & Schulze E.D. (2014). Soil Organic Carbon and Total Nitrogen Gains in an Old Growth Deciduous Forest in Germany. PLoS ONE, 9(2), e89364.

+ Open protocol

+ Expand

Quantitative Analysis of Volatile Fatty Acids

Check if the same lab product or an alternative is used in the 5 most similar protocols

For determination of total volatile fatty acids (VFA) content and ratio of VFAs and alkalinity (VFA/TAC), samples were centrifuged for 15 min and 4,696 × g at 4 °C. 10 mL of the liquid phase were then titrated with 0.05 M sulfuric acid (Carl Roth GmbH, Karlsruhe, Germany) to pH values of 5.00, 4.40, 4.30 and 4.00. VFA as well as VFA/TAC were measured in triplicates and calculated as described elsewhere⁴⁶. Composition of VFA was analyzed by atres Analytik (München, Germany) using an in-house gaschromatographic approach. Contents of following VFAs were measured: acetic acid, propionic acid, isobutyric acid, butyric acid, isovaleric acid, valeric acid, hexanoic acid and heptanoic acid.
For analyzing elemental composition (C, N, S) samples were dried at 50 °C for 48 h. Afterwards samples were grinded using mortar and pestle. 10 mg of each sample were oxidized in the combustion tube of the elemental analyzer Vario EL II (Elementar Analysensysteme GmbH, Langenselbold, Germany) at 1,150 °C according to manufacturer’s instructions. Sulphanilic acid (Sigma-Aldrich Chemie GmbH, Taufkirchen, Germany) was used as standard. All analyses were performed in triplicate measurements.

Buettner C., von Bergen M., Jehmlich N, & Noll M. (2019). Pseudomonas spp. are key players in agricultural biogas substrate degradation. Scientific Reports, 9, 12871.

+ Open protocol

+ Expand

Elemental Analysis of Plant Tissues

Check if the same lab product or an alternative is used in the 5 most similar protocols

Roots were washed in hand-hot water to remove attached soil particles and other material, rinsed with deionised water and transferred into paper bags. Leave, fine root, and soil samples were dried at 60°C for 72 h. First- and second-order roots of each root sample were cut off with scissors and used for analyses (after Pregitzer et al., 2002 ). Fine roots were ground manually, leaves (without petiole and rachis) and soil were ground with a ball mill (Cornelissen et al., 2003 ), subsequently dried for another 24 h, and transferred into tin capsules for C and N analyses. Analyses were performed using an elemental analyser (Vario EL II, Elementar Analysensysteme GmbH, Hanau, Germany). C and N concentration is given as relative mass proportion of the element (in %) per sample mass. C:N ratio was calculated from C and N mass proportions.

Ferlian O., Wirth C, & Eisenhauer N. (2017). Leaf and root C-to-N ratios are poor predictors of soil microbial biomass C and respiration across 32 tree species. Pedobiologia, 65, 16-23-.

+ Open protocol

+ Expand

Faecal Output in Unmedicated Rams

Check if the same lab product or an alternative is used in the 5 most similar protocols

Five Suffolk and White Dorper rams with an average weight of 115.95 ± 14.82 kg and daily faecal production of 3.63 ± 0.80 kg were kept in slatted sheepfolds without receiving any drug treatment for 10 months. They were fed a diet composed of 44.3% concentrate and 55.7% roughage (ryegrass (Lolium multiflorum Lam.) hay), following the nutrient requirements established by the NRC [31 ]. The diet was provided twice a day ad libitum, with a 10% daily leftover not to limit feed intake. Canvas bags were used for the total collection of faeces for 24 h.
The amount of faeces collected in 24 h was oven dried at 65°C for 72 h, ground, sieved through a 2 mm sieve, and stored in polyethylene plastic bags in the dark. The samples contained 33% dry matter, 1.7% N, and 37.9% C on a DM basis. The C and N analyses were performed using the Vario EL II element analyzer (Elementar Analysensysteme GmbH, Hanau, Germany).

Gilaverte Hentz S., Reyes Reyes F.G., Kaschuk G., Bittencourt de Oliveira L., Machado Fernandes M.A, & Gomes Monteiro A.L. (2024). Does Faeces Excreted by Moxidectin-Treated Sheep Impact Coprophagous Insects and the Activity of Soil Microbiota in Subtropical Pastures?. Scientifica, 2024, 1960065.

+ Open protocol

+ Expand

Soil Organic Carbon and Microbial Biomass Measurement

Check if the same lab product or an alternative is used in the 5 most similar protocols

A 6 g subsample of fresh mineral soil was extracted with 30 ml of 0.05M K₂SO₄ within 24 h of soil sampling. Another 6 g subsample was fumigated with CHCl₃ for 24 h in vacuum to release the nutrients from the microbial biomass (fumigation-extraction method; Jenkinson and Powlson, 1976 (link)), after which the soil was also extracted with 0.05 M K₂SO₄ as above. Dissolved organic C (DOC) in fumigated and non-fumigated K₂SO₄ extracts was determined with a vario TOC cube (Elementar Analysensysteme GmbH, Hanau) and microbial C (C_micro) was determined from the difference of DOC between fumigated and non-fumigated subsamples. We were only interested in relative differences among treatments, so the concentrations in the microbial fraction presented here were not corrected for extraction efficiency.
Total soil inorganic C, organic C (SOC), total soil N (TN), total litter C, and total litter N were determined from dry and homogenized soil and litter samples by dry combustion with an Elemental Analyzer (VarioMax CN, Elementar Analysensysteme GmbH, Hanau, Germany for soil samples and Vario EL II, Elementar Analysensysteme GmbH, Hanau, Germany for litter samples). C:N ratios of soil (C:N_soil) and leaf litter (C:N_soil) were calculated on a mass basis. The relative accessibility of the DOC pool was calculated as its ratio to the SOC pool. All fractions are presented relative to dry mass.

Marañón-Jiménez S., Radujković D., Verbruggen E., Grau O., Cuntz M., Peñuelas J., Richter A., Schrumpf M, & Rebmann C. (2021). Shifts in the Abundances of Saprotrophic and Ectomycorrhizal Fungi With Altered Leaf Litter Inputs. Frontiers in Plant Science, 12, 682142.

+ Open protocol

+ Expand

About PubCompare

Our mission is to provide scientists with the largest repository of trustworthy protocols and intelligent analytical tools, thereby offering them extensive information to design robust protocols aimed at minimizing the risk of failures.

We believe that the most crucial aspect is to grant scientists access to a wide range of reliable sources and new useful tools that surpass human capabilities.

However, we trust in allowing scientists to determine how to construct their own protocols based on this information, as they are the experts in their field.

Ready to get started?

Revolutionizing how scientists
search and build protocols!