scholarly journals Particle separation from road runoff by a decentralised lamella system – laboratory tests and experiences in the field

2017 ◽  
Vol 75 (9) ◽  
pp. 2056-2063 ◽  
Author(s):  
J. Fettig ◽  
V. Pick ◽  
H. Liebe
Keyword(s):  
Laboratory Tests ◽  
Separation Efficiency ◽  
Particle Separation ◽  
Field Studies ◽  
Test Methods ◽  
Road Runoff ◽  
Test Procedures ◽  
Mineral Particles ◽  
Settling Behaviour ◽  
Organic Particles

A new decentralised settling system based on the principle of lamella separation was developed for the treatment of road runoff. Two different laboratory test methods, the DIBt (Deutsches Institut für Bautechnik) procedure and our own approach, were applied in order to evaluate the efficiency of the system based on the separation of fine mineral particles and a mixture of mineral and organic particles, respectively. Overall efficiencies (88% after DIBt and 61% according to our own method) were comparable to results obtained for commercial systems. The lamella system was then applied in the field for 1 year to treat runoff from a road area of 420 m2. The amount of solids separated that was calculated from a mass balance (10.1 kg) was consistent with the amount of sediments measured (8.6 kg). However, the average separation efficiency was only 30% in the field study. This is related to the size and composition of the particles in runoff, which are not represented well by the material used for the test procedures. It is concluded that the test methods should be improved, and that more field studies are needed in order to obtain a better understanding of the settling behaviour of particles in road runoff.

The Choice of Test Methods in Site Investigations

1986 ◽  
Vol 2 (1) ◽  
pp. 289-297 ◽  
Author(s):  
A. Marsland
Keyword(s):  
Laboratory Tests ◽  
Test Methods ◽  
Careful Consideration ◽  
Engineering Properties ◽  
Soil Parameters ◽  
Test Procedures ◽  
Site Investigations ◽  
Soil Fabric ◽  
Design Requirements

AbstractThe appropriate choice of sampling methods, laboratory tests and in situ tests depends upon the type of structure or earthwork being considered, the nature of the ground influenced by the construction and the required accuracy of the prediction. To obtain optimum results requires considerable experience of the design requirements and potential construction problems as well as the test methods and their range of application. Some methods are particularly useful for obtaining continuous profiles and giving a rough indication of the engineering properties while others are designed to provide more basic soil parameters. The results obtained may be sensitive to changes in equipment details, test procedures and methods of interpretation.When empirical relationships are invoked, care is necessary to ensure that identical equipment and procedures have been used and that the correlations have been obtained in similar soils. The degree to which the volumes of soil tested are representative of the soil in the mass is important. Factors such as the orientation of the maximum stresses applied during the tests relative to the directions of the macro fabric features, the degree of stress anisotropy, the directions of the stresses applied to the structure and the effects of disturbance during sampling and insertion of in situ devices need careful consideration.Test data from the most appropriate in situ and laboratory tests should be integrated with soil fabric studies in order to produce the best overall assessments.

Reliability of Laboratory Tests for the Control of Oral Anticoagulation

1974 ◽  
Vol 32 (02/03) ◽  
pp. 483-491
Author(s):  
E. A Loeliger ◽  
M. J Boekhout-Mussert ◽  
L. P van Halem-Visser ◽  
J. D. E Habbema ◽  
H de Jonge
Keyword(s):  
Human Brain ◽  
Laboratory Tests ◽  
Test Procedure ◽  
Rabbit Brain ◽  
Normal Range ◽  
Test Procedures ◽  
Discrimination Power ◽  
Power Of The Test ◽  
Assay Procedure ◽  
Low Sensitivity

SummaryThe present study concerned the reproducibility of the so-called prothrombin time as assessed with a series of more commonly used modifications of the Quick’s onestage assay procedure, i.e. the British comparative reagent, homemade human brain thromboplastin, Simplastin, Simplastin A, and Thrombotest. All five procedures were tested manually on pooled lyophilized normal and patients’ plasmas. In addition, Simplastin A and Thrombotest were investigated semiautomatically on individual freshly prepared patients’ plasmas. From the results obtained, the following conclusions may be drawn :The reproducibility of results obtained with manual reading on lyophilized plasmas is satisfactory for all five test procedures. For Simplastin, the reproducibility of values in the range of insufficient anticoagulation is relatively low due to the low discrimination power of the test procedure in the near-normal range (so-called low sensitivity of rabbit brain thromboplastins). The reproducibility of Thrombotest excels as a consequence of its particularly easily discerned coagulation endpoint.The reproducibility of Thrombotest, when tested on freshly prepared plasmas using Schnitger’s semiautomatic coagulometer (a fibrinometer-liJce apparatus), is no longer superior to that of Simplastin A.The constant of proportionality between the coagulation times formed with Simplastin A and Thrombotest was estimated at 0.64.Reconstituted Thrombotest is stable for 24 hours when stored at 4° C, whereas reconstituted Simplastin A is not.The Simplastin A method and Thrombotest seem to be equally sensitive to “activation” of blood coagulation upon storage.

Oxygen transfer in gravity flow sewers

1995 ◽  
Vol 31 (7) ◽  
pp. 127-135 ◽  
Author(s):  
P. Balmér ◽  
M. Tagizadeh-Nasser
Keyword(s):  
Energy Dissipation ◽  
Oxygen Transfer ◽  
Laboratory Tests ◽  
Field Studies ◽  
Gravity Flow ◽  
Clean Water

Oxygen transfer to water in gravity flow pipes has been studied in a 24 m long, 0.225 m diameter sewer. Laboratory tests were conducted where the slope and flow in the sewer could be varied independently. The clean water reaeration test was used to determine the oxygen transfer. The KL value for the oxygen transfer was found to be a function of energy dissipation and mean hydraulic depth. The results are discussed in relation to oxygen transfer determinations in flumes and field studies of oxygen transfer in sewers.

The fate of detergent surfactants in sewer systems

1995 ◽  
Vol 31 (7) ◽  
pp. 321-328 ◽  
Author(s):  
E. Matthijs ◽  
G. Debaere ◽  
N. Itrich ◽  
P. Masscheleyn ◽  
A. Rottiers ◽  
...  
Keyword(s):  
Fatty Alcohol ◽  
Half Life ◽  
Laboratory Tests ◽  
Field Experiments ◽  
Sewage Treatment ◽  
Field Studies ◽  
Municipal Sewage ◽  
Alcohol Ethoxylate ◽  
Rapid Reduction ◽  
Laboratory Findings

The fate of detergent surfactants in the sewer can be studied both in laboratory tests and in field experiments. The laboratory studies can be used to determine the rate of disappearance of a test molecule as a function of residence time and estimate its half-life in a given habitat. In addition, important information can be obtained on the mechanism of degradation. Field studies can determine the actual environmental concentrations of surfactants in raw sewage which can then be compared with the expected concentration based on consumption volumes. The difference between the measured and predicted concentration provides an estimate for the disappearance of the test chemical during its travel in the sewer and confirms the results of the laboratory tests. This paper focuses on the fate of a number of important representative anionic, nonionic and cationic surfactants, in the sewer. The results of laboratory die-away studies showed that, in general, the half-life for disappearance in the sewer was in the order of hours for Fatty Alcohol Ethoxylate (AE), Fatty Alcohol Ethoxy Sulphate (AES) and Di-Ethyl-Ester Di-methyl-Ammonium Chloride (DEEDMAC). These laboratory findings for AES were confirmed by monitoring actual raw sewage reaching municipal sewage treatment plants. In addition, a field study demonstrated that the concentration of glucose amides (GA) is considerably reduced during its travel in the sewer. These complementary laboratory and field studies provide key information for the safety assessment of surfactants. They demonstrate that the concentration of surfactants can be significantly reduced in the sewer resulting in a rapid reduction of the environmental loading, which is particularly important in environmental situations where inadequate or no sewage treatment exists.

scholarly journals Quantitative determination of tolfenamic acid and its pharmaceutical formulation using FTIR and UV spectrometry

2013 ◽  
Vol 11 (9) ◽  
pp. 1533-1541 ◽  
Author(s):  
Sofia Ahmed ◽  
Muhammad Sheraz ◽  
Ceyla Yorucu ◽  
Ihtesham Rehman
Keyword(s):  
Uv Spectroscopy ◽  
Peak Height ◽  
Test Methods ◽  
Tolfenamic Acid ◽  
Test Procedures ◽  
Titration Method ◽  
Uv Spectrometry ◽  
Analytical Wavelength ◽  
Ft Ir ◽  
Tablet Dosage

AbstractAbstract The quantitative analysis of Tolfenamic Acid (TA) both as a pure compound and in tablet dosage form has been carried out using FT-IR and UV spectroscopy. In the FT-IR method, a number of characteristic absorption peaks were examined that could be used for analytical purpose. The analysis was carried out by preparing calibration curves of peak height/area versus TA content using two points baseline correction with fixed location, and the data was also analyzed through PLS regression model. In the UV method, ethanolic solutions of the drug were analyzed at 288 nm (λmax) using 480 as the value of A (1%, 1 cm) at the analytical wavelength. The results have been compared statistically for recovery, precision, accuracy and linearity with the British Pharmacopoeial titration method that showed good validity of both test procedures. The two test methods exhibited good recovery of TA with an accuracy of 99.75–100.83% and 99.53–100.11% by FTIR spectrometry for peak height and area respectively and 100.21% for UV method. However, UV spectrometry was found to be more accurate and precise on the basis of statistical evaluation and hence can be employed in the quality control of TA in pharmaceuticals as an alternative to the titration method. Graphical abstract

A New Approach to Fit Bearing Performance to Advanced Gas Engine Technology

2002 ◽  
Author(s):  
Thomas Rumpf ◽  
Johannes Humer ◽  
Elisabeth Schneiderbauer ◽  
Michael Putz
Keyword(s):  
Life Time ◽  
Test Methods ◽  
Hydrodynamic Performance ◽  
Test Procedures ◽  
Gas Engine ◽  
Simulation Tools ◽  
Bearing Materials ◽  
Engine Components ◽  
Long Term Behavior

Gas engines get an increasing market share compared to four stroke engines, especially in the field of energy systems. Under these special firing conditions engine components are stressed differently than in traditional diesel engines. This particularly is the case for bearings. In order to supplement the knowledge base for bearing performance under these aggravated conditions, special test methods have been developed to find out reasons for premature bearing failure characteristics. In combination with experience from the long term behavior of different bearing types in different gas engine applications, this data allows the development of improved bearing materials as well as bearing designs. Using this knowledge in combination with advanced simulation tools, a bearing supplier can offer assistance to select adequate bearing designs, give a life time prediction and in case of unexpected phenomena, redesign recommendations. The paper presents reasons and influences for life time limitations as well as different risk factors for available bearing types and situations. Based on field experience and data from the advanced bearing test procedures, values for bearing performance are given. Data for hydrodynamic performance, tribological properties and emergency running behavior, cavitation resistance, wear resistance and last, but not least corrosion resistance against active sulfur and halogens will be given for traditional and newly developed bearing materials. A short view into the future will finish the presentation.

Cyclic Flow Experiments of a Fine Particle Separation Hydrocyclone

2007 ◽  
Author(s):  
Lixin Zhao ◽  
Minghu Jiang
Keyword(s):  
Flow Condition ◽  
Fine Particle ◽  
Fine Particles ◽  
Separation Efficiency ◽  
Amplitude Ratio ◽  
Particle Separation ◽  
Separation Performance ◽  
Period Ratio ◽  
Cyclic Flow ◽  
Signal Type

Basic separating principle of hydrocyclones and the cyclic experimental research facilities are introduced. The difficulty of separating fine particle is described. Based on a solid-liquid hydrocyclone used for separating fine particles, effect of cyclic flow condition on hydrocyclone’s performance is studied. Effects of cyclic period ratio, cyclic flowrate amplitude ratio, Reynolds number, gas liquid ratio, and the cyclical signal type on the hydrocyclone’s fine particle separation performance, especially on relative overflow purifying rate were studied in detail. The results show that the separation efficiency of the hydrocyclone operated under cyclic flow condition can be higher than that in steady condition, when the cyclic period ratio is about 0.68 and the cyclic flowrate amplitude ratio is about 2%. Rectangular wave seems to be the best cyclic signal for enhancing the hydrocyclone’s separation efficiency. The cyclical change of flowrate leads to the increasing of hydrocyclone’s energy consumption to some extent, while the increasing amount is very less, which is no more than 3% in general.

Methods to Evaluate Cleaners and Sanitizers

1982 ◽  
Vol 45 (13) ◽  
pp. 1257-1260 ◽  
Author(s):  
DALE L. SCHEUSNER
Keyword(s):  
Test Methods ◽  
Test Method ◽  
Test Results ◽  
Standard Laboratory ◽  
Test Procedures ◽  
Laboratory Methods ◽  
Product Use ◽  
Cellulose Sponge ◽  
Equivalent Test ◽  
Recovery Methods

Methods to evaluate germicides can be grouped into three categories: standard laboratory tests, in-use tests and simulated-use tests. Standard laboratory methods, such as the Available Chlorine Germicidal Equivalent test, are specifically defined for reproducibility in any laboratory by any operator, but the test results often lack relevance to actual product-use conditions. In-use test methods are relevant to product-use; however, in-use test procedures do not permit proper controls to be included in the organism recovery methods. Contact plates give an estimate of organism numbers which is only 25% of the theoretical number of organisms present. Organism recovery using a swab, cellulose sponge or tube sampler give estimates of organisms ranging from 91 to 111% of theoretical. The tube sampler is a 1-in. length of flexible tubing having a 1-in. interior diameter and a smooth end, which can make a water-tight seal on a flat surface. Simulated use testing yields data which are relevant to actual product-use. A cafeteria tray is soiled, inoculated and cleaned in a manner to simulate actual product-use. This test method permits the necessary controls to be used. Tray-test reproducibility is as good as that of the other recovery methods tested and organism recovery is quantitative. The tray test provides a means for determining biological cleaning where the effect of both cleaning and germicidal activity are measured together.

SHORELINE CLEANSING BY INTERACTIONS BETWEEN OIL AND FINE MINERAL PARTICLES

1995 ◽  
Vol 1995 (1) ◽  
pp. 219-227 ◽  
Author(s):  
James R. Bragg ◽  
Edward H. Owens
Keyword(s):  
Potential Role ◽  
Sea Water ◽  
Field Studies ◽  
Low Energy ◽  
Oil Removal ◽  
Oil Droplets ◽  
Mineral Particles ◽  
Treatment Techniques ◽  
Oil In Water ◽  
Flocculation Process

ABSTRACT Interactions of fine mineral particles with oil stranded on shorelines following spills has been shown to be an important natural cleansing process, capable of accelerating oil removal in most environments, and particularly in low energy environments where wave action and abrasion are negligible. This process involves formation of solids-stabilized oil-in-water emulsions by flocculation of micron-sized mineral fines with oil droplets in the presence of water containing ions (such as sea water). Once flocculated, the oil droplets do not coalesce, and the oil no longer adheres strongly to shoreline sediments, facilitating its removal and dispersion by waves and tidal currents. The importance of the flocculation process to the rate of oil removal from sediments, the conditions needed for the process to occur, and the properties of the resulting floe have been studied in detail for the Exxon Valdez spill. Its potential role in shoreline cleansing also has been studied for other recent spills: Metula (1974, Chile), Arrow (1970, Nova Scotia), BIOS test spill (1981, Cape Hatt, Northwest Territories), Nosac Forest (1993, Tacoma, Washington), and Fred Bouchard (1993, Tampa, Florida). This paper summarizes the various laboratory and field studies and discusses the findings within the contexts of natural shoreline cleansing, and the use of certain treatment techniques.

Methods to Determine Low-Constraint Fracture Toughness: Review and Progress

2016 ◽  
Author(s):  
Xian-Kui Zhu
Keyword(s):  
Fracture Toughness ◽  
Test Methods ◽  
Standard Test ◽  
Initiation Toughness ◽  
Fracture Toughness Test ◽  
Crack Tip Opening Displacement ◽  
Test Procedures ◽  
Opening Displacement ◽  
Resistance Curves ◽  
Low Constraint

Fracture toughness is often described by the J-integral or crack-tip opening displacement (CTOD) for ductile materials. ASTM, BSI and ISO have developed their own standard test methods for measuring fracture initiation toughness and resistance curves in terms of the J and CTOD using bending dominant specimens in high constraint conditions. However, most actual cracks are in low constraint conditions, and the standard resistance curves may be overly conservative. To obtain more realistic fracture toughness for actual cracks in low-constraint conditions, different fracture test methods have been developed in the past decades. To facilitate understanding and use the test standards, this paper presents a critical review on commonly used fracture toughness test methods using standard and non-standard specimens in reference to the fracture parameters J and CTOD, including (1) ASTM, BSI and ISO standard test methods, (2) constraint correction methods for formulating a constraint-dependent resistance curve, and (3) direct test methods using the single edge-notched tension (SENT) specimen. This review discusses basic concepts, basic methods, estimation equations, test procedures, historical efforts and recent progresses.

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