Feasibility of using of accelerated test methods for determination of frost-resistance for concrete

The article presents the results of studies of innovative materials in the field of testing frost resistance. In fact, present accelerated methods for the determination of concrete frost resistance have high labour consuming and low effectiveness. Moreover there is no such accelerated methods which can be sufficiently applicable fro different innovative concretes, for example, concretes with SAP or self-compacting concrete and so on. Therefore, it is highly important to investigate new accelerated test method with high operability, efficiency and sufficient precision. Previously, two new methods were developed. The main purpose of the research is to compare these methods by evaluation of their technology and accuracy and, consequently, to identify the more sustain and efficient one. First method is based on estimation of energy release due to mechanical fracture and thermo cycling. Second method consists of the calculation value z (relation between relative decreasing of strength and relative strain in the direction perpendicular to compression) and replacement of thermo cycles by mechanical cycles. Both methods have high operability and do not take a lot of time, in was tested on the 10 specimens made of concrete and results were compared with values derived by standard method.

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MicroVal: A European Approach to the Certification of New Microbiological Methods

Journal of Food Protection ◽

10.4315/0362-028x-61.11.1579 ◽

1998 ◽

Vol 61 (11) ◽

pp. 1579-1582 ◽

Cited By ~ 2

Author(s):

ROY P. BETTS ◽

IRENE M. F. RENTENAAR

Keyword(s):

Method Validation ◽

Limit Of Detection ◽

Collaborative Study ◽

Reference Method ◽

Test Methods ◽

International Standards ◽

Test Method ◽

Eu Member States ◽

New Methods ◽

Microbiological Methods

In recent years, food microbiologists have seen the development of a range of nonstandard methods designed to enumerate or determine the presence of various microorganisms in food products. Generally the new methods are designed to give the microbiologist advantages, such as greater automation or faster results, over standard conventional methods. The new methods, however, have often not been thoroughly tested to give the end user confidence in the results. In order to generate data to show that new methods give results that are comparable with standard methods, they must be validated. A number of validation schemes have been developed in various countries throughout the world. There has not, however, been an acceptable scheme recognized throughout Europe. The MicroVal project has been involved in the development of a European microbiological method validation and certification scheme; it involves 21 partners from 7 EU member States. New methods that are tested by the MicroVal system will undergo initial testing in a single expert laboratory, to establish the test's specificity, limit of detection, relative accuracy, sensitivity, and linearity. This testing will be followed by a collaborative study in a minimum of eight laboratories, which will be used to determine the test precision, repeatability, and reproducibility. All results will be assessed by two expert reviewers who will recommend or reject the test. Tests that are recommended will be finally accepted by a MicroVal committee. The committee will pass its comments to one of several certification bodies (working together through a memorandum of understanding) who will certify that the new method gives results that are equivalent to the reference method used throughout the validation work. The technical rules that describe the work required to certify a method are currently being considered by the European Committee for Standardization (CEN), with the objective that the rules will become a CEN standard for the certification of new test methods. When this objective has been achieved the rules will become an International Standards Organization (ISO) standard for new test method validation.

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ACCELERATED TEST METHOD FOR DETERMINATION OF ODOR CONTROL DEVICES

Annals of the New York Academy of Sciences ◽

10.1111/j.1749-6632.1964.tb45093.x ◽

1964 ◽

Vol 116 (2 Recent Advanc) ◽

pp. 613-620 ◽

Cited By ~ 1

Author(s):

L. J. Czerwonka ◽

R. J. Boylan ◽

D. J. Gonzalez

Keyword(s):

Test Method ◽

Odor Control ◽

Accelerated Test ◽

Control Devices

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Study on the Bearing Capacity Test for the Saline Soil Soft Ground

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.587-589.947 ◽

2014 ◽

Vol 587-589 ◽

pp. 947-951

Author(s):

Jun Yong Liu ◽

Liu Jun Zhang

Keyword(s):

Bearing Capacity ◽

Saline Soil ◽

Test Methods ◽

Test Method ◽

Soft Ground ◽

Characteristic Value ◽

Soft Foundation

The test methods provided by current related "specifications" do not apply to saline soil soft foundation bearing capacity test. Through discussing the limitations of the related specifications and based on the experience on saline soil soft ground capacity test, the paper made some improvements of test on such aspects: conditions of loading and stopping load, determination of the characteristic value of the ground bearing capacity and evaluation, the paper also put forward the saline soil soft ground capacity test method.

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Analysis of Vitamin A in Multivitamin Products

The Bulletin of the Scientific Centre for Expert Evaluation of Medicinal Products ◽

10.30895/1991-2919-2021-11-174-184 ◽

2021 ◽

Vol 11 (3) ◽

pp. 174-184

Author(s):

A. S. Alekseeva ◽

T. B. Shemeryankina ◽

M. N. Lyakina ◽

M. S. Smirnova ◽

E. P. Fedorova ◽

...

Keyword(s):

Vitamin A ◽

High Performance ◽

Beta Carotene ◽

Test Methods ◽

Retinyl Palmitate ◽

Test Method ◽

Medicinal Products ◽

Retinyl Acetate ◽

Preliminary Purification

Vitamin A is present in multivitamin products mainly in the form of retinol esters: retinyl acetate, retinyl palmitate, and beta carotene—retinol precursor (dimer) found in plants, which is capable of converting into retinol in liver cells. Retinol is determined in medicinal products primarily by high performance liquid chromatography (HPLC), with preliminary purification and vitamin isolation by liquid-liquid extraction. However, scientific literature also describes other methods of sample preparation and analysis of such compounds. An important issue is differentiation of vitamin A from other fat-soluble vitamins often included as components in multivitamin products. The aim of the study was to analyse and summarise data on current methods used for determination of vitamin A and its derivatives in medicinal products. The authors analysed the range of vitamin A products authorised in the Russian Federation, and the test methods described in their product specification files. The study demonstrated that the test method most often used for determination of retinol esters was HPLC with isocratic elution mode using octadecylsilyl packing in the reverse-phase mode, and, less frequently, aminopropylsilyl packing in the normal phase mode. Determination of beta carotene in medicinal products is most often performed using spectrophotometry.

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The modern methods of pin-type bearing test of metallic materials

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2019-85-7-41-49 ◽

2019 ◽

Vol 85 (7) ◽

pp. 41-49

Author(s):

Yaroslava V. Sulimina ◽

Nikolay O. Yakovlev ◽

Vladimir S. Erasov ◽

Aleksey Yu. Ampilogov ◽

Andrey N. Polyakov ◽

...

Keyword(s):

Elastic Modulus ◽

Test Procedure ◽

Test Methods ◽

Test Method ◽

Strength Characteristics ◽

Metallic Materials ◽

Bearing Strength ◽

Bearing Stress ◽

The Impact

The special features of various bearing deformation measurements for pin-type bearing tests of metallic materials are considered along with their impact on the magnitude of the «bearing elastic modulus» and bearing stress. These bearing test methods are present in ASTM and various institutional standards, though no state standard (GOST, GOST R) is currently available for bearing test method of metallic materials. Analysis of additional deformations which arise in determining the degree of hole bearing deformation is carried out. A set of sources of additional deformations is shown to be characteristic for each test procedure and is attributed to the design features of the device, the site and a way of mounting the extensometer. Additional deformations can be both tensile and compressive. It is shown that the impact of additional deformations on the «bearing elastic modulus» is limited to 14% for different procedures. No difference between the methods is revealed with regard to determination of the strength characteristics. At the same time the dispersion decreases with increase in plastic deformation and for bearing deformation about 4% the variation coefficient for all methods is no more than 1%. Advantages and shortcomings of the bearing test methods which affect the reproducibility of the results are considered. The effect of the specimen geometry on the bearing characteristics is considered. It is shown that increase both in the distance from the edge of the bearing specimen to the center of the hole for 1163T, VT6ch, 30KhGSA alloys and residual bearing deformation up to 6%, increase bearing strength characteristics.

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