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While offering great promise for the future, the use of telematics in goods transport has so far been the focus of little research, although the many applications ranging from logistics to computer aids for drivers and electronic data interchange (EDI) will radically change freight transport markets. International specialists at Round Table 78 compare notes on such vital issues as: the strategies adopted in the sector; forms of standardization called for; productivity gains and the obstacles involved.
Experience has shown that there is a very close relationship between the geographical distribution of activities and the location of transport infrastructures, a relationship that is becoming evident again today as high-speed railway lines are built or enter the planning stage. This report seeks to determine what influence these lines will have on the regions served, particularly in the light of experience with the TGV Sud-Est in France.
The test method described in this Test Guideline, is intended to define the lethal and sub-lethal effects of chemicals on the early life stages of the species tested.
The early-life stages of fish are exposed to ,at least, five concentrations of the test substance dissolved in water, preferably under flow-through conditions, or where appropriate, semi-static conditions. The test starts with placing fertilised eggs (at least 60) in the test chambers and continues at least until all the control fishes are free-feeding. Lethal and sub-lethal effects are assessed and compared with control values to determine the lowest observed effect concentration and the no observed effect concentration. The study report should include measurement of the concentrations of the test substance in water at regular intervals (five at least), the dissolved oxygen, pH, total hardness and salinity, fish weight and length, as well as the observations of abnormal appearance, abnormal behaviour, hatching and survival.
This Test Guideline describes six methods that permit the screening of chemicals for ready biodegradability in an aerobic aqueous medium. The methods are: the DOC Die-Away, the CO2 Evolution (Modified Sturm Test), the MITI (I) (Ministry of International Trade and Industry, Japan), the Closed Bottle, the Modified OECD Screening and the Manometric Respirometry.
A solution, or suspension, of the test substance, well determined/described, in a mineral medium is inoculated and incubated under aerobic conditions in the dark or in diffuse light. The running parallel blanks with inoculum but without test substance permits to determined the endogenous activity of the inoculum. A reference compound (aniline, sodium acetate or sodium benzoate) is run in parallel to check the operation of the procedures. Normally, the test lasts for 28 days. At least two flasks or vessels containing the test substance plus inoculum, and at least two flasks or vessels containing inoculum only should be used; single vessels are sufficient for the reference compound. In general, degradation is followed by the determination of parameters such as DOC, CO2 production and oxygen uptake. The pass levels for ready biodegradability are 70% removal of DOC and 60% of ThOD or ThCO2 production for respirometric methods. These pass values have to be reached in a 10-d window within the 28-d period of the test.
This Test Guideline describes the Zahn-Wellens/EMPA Test. It is used to determine inherent biodegradability.
A mixture containing the non-volatile and water soluble test substance, mineral nutrients and a relatively large amount of activated sludge in aqueous medium is agitated and aerated at 20-25°C in the dark or in diffuse light, for up to 28 days. Blank controls, containing activated sludge and mineral nutrients but no test substance, are run in parallel. The functional capability of the activated sludge is tested using a reference compound (ethylene glycol, diethylene glycol, lauryl sulfonate or aniline). In a typical run 1 or 2 vessels for the test suspension and for the inoculum blank, 1 for procedure control are used. The biodegradation process is monitored by determination of DOC, Dissolved Organic Carbon, (or COD, Chemical Oxygen Demand) in filtered samples, taken at daily or other time intervals. It is mandatory to follow DOC in the test suspension and inoculum blanks in parallel. The ratio of eliminated DOC (or COD), corrected for the blank, after each time interval, to the initial DOC value is expressed as the percentage biodegradation at the sampling time. The percentage biodegradation is plotted against time to give the biodegradation curve. The test is considered valid if the procedural control shows the removal of the reference compound by at least 70% within 14d and if DOC (or COD) in the test suspension is removed relatively gradually over days or weeks, since this indicates biodegradation.
This Test Guideline describes two methods for biodegradability in seawater.
The shake flask method consists on dissolution of a pre-determined amount of the test substance in the test medium to yield a concentration of 5-40 mg/l dissolved organic carbon (DOC). Five flasks, at least, should be used: two for the test suspension, two for the blank and one for procedure control. The solution of the test substance in the test medium is incubated, under agitation in the dark or in diffuse light under aerobic conditions, at a fixed temperature which will normally be within the range 15-20°C. The recommended maximum test duration is about 60 days. Degradation is followed by DOC measurements (ultimate degradation) and, in some cases, by specific analysis (primary degradation). The closed bottle method consists on dissolution of a pre-determined amount of the test substance in the test medium in a concentration of usually 2-10 mg/l (one or more concentrations may be used).The solution is kept in a filled closed bottle in the dark in a constant temperature bath or enclosure controlled within a range of 15-20°C. The degradation is followed by oxygen analyses over a 28-day period but if the blank biological oxygen demand value remains within the 30 per cent limit, the test could be prolonged. Twenty-four bottles at least are used (8 for test substance, 8 for reference compound and 8 for sweater plus nutriment). All analyses are performed on duplicate bottles. Four determinations of dissolved oxygen, at least, are performed (day 0, 5, 15 and 28) using a chemical or electrochemical method.
Analysts and policy makers have made increasing use of patent indicators to analyse the rate and direction of technological activity. The Patents Manual, issued in 1994, provides information on how patent data can be used as indicators, and also shows how these can be linked to other statistics on science, technology and economic activity (R&D, scientific publications, trade, production, etc.).
As the countries of Central and Eastern Europe undergo radical economic upheavals, the question of pan-European transport is brought very sharply into focus. The transport system cannot be viewed simply in terms of the volume of traffic moving from one particular place to another but must be seen as a whole both theoretically and pragmatically in terms of specific projects. What infrastructure is to be selected? Which method of organising transport "markets" is to be preferred? How can needs logically dictated by urgency -- catering to expanding traffic flows despite inadequate transport networks -- be reconciled with such longer-term imperatives as environmental protection or integrating Central and Eastern Europe into a vast area of cultural and economic relations? Specialists attending Round Table 95 addressed all of these issues and tried to discern realistic boundaries for what can be accomplished today.
The Frascati Manual, issued in 1994, is the basic international source of methodology for collecting and using research and development statistics. This fifth edition reflects recent changes in the structure of national science and technology systems and revisions in standard international classifications.
This Test Guideline lists methods for determining the density of liquids and solids, giving only a very succinct description of them. The density of a substance is the quotient of its mass and its volume and is expressed in kg/m3.
Several methods are for liquid substance only: hydrometer, immersed body method (both are buoyancy methods) and oscillating densitometer. These methods are applicable to liquids with a dynamic viscosity below 5 Pa s for hydrometer and oscillating densitometer and below 20 Pa s for immersed body method. The method for solids only is the air comparison pycnometer. The volume of a sample of the solid is measured in air or in an inert gas in a calibrated cylinder of variable volume. After concluding the volume measurement, the sample is weighed. The methods for liquids and solids are the hydrostatic balance (a buoyancy method) and the pycnometer. The dynamic viscosity of liquids to be investigated should not exceed 5 Pa s for hydrostatic balance, and should not be above 500 Pa s for pycnometer.
The test substance is administered in graduated doses to several groups of males and females.
Males should be dosed for a minimum of four weeks. Females should be dosed throughout the study, so approximately 54 days. This Test Guideline is designed for use with the rat. It is recommended that each group be started with at least 10 animals of each sex. Generally, at least three test groups and a control group should be used. Dose levels may be based on information from acute toxicity tests or on results from repeated dose studies. The test substance is administered orally and daily. The limit test corresponds to one dose level of at least 1000 mg/kg body weight. The results of this study include measurements (weighing, food/water consumption) and daily and detailed observations, preferably each day at the same time, as well as gross necropsy and histopathology. The findings of this toxicity study should be evaluated in terms of the observed effects, necropsy and microscopic findings. Because of the short period of treatment of the male, the histopathology of the testis and epididymus must be considered along with the fertility data, when assessing male reproductive effects.
This Test Guideline is used in the assessment and evaluation of the toxic effects of organophosporus substances.
Daily doses of the test substance are administered orally (preferably by gavage or administration of gelatin capsules) to domestic laying hens (aged 8 to 12 months) for 28 days. The animals are observed at least daily until 14 days after the last dose. Biochemical measurements are undertaken on hens randomly selected from each group after the last dose. Two weeks after the last dose, the remainder of the hens are killed and histopathological examination is undertaken. The treatment group should contain at least 12 hens. Generally, at least three treatment groups should be used. The highest dose level should be chosen with the aim of inducing toxic effects; thereafter a descending sequence of dose levels should be selected. A limit test may be performed if no effects would be expected at a dose of 1000 mg/kg bw/d. The results of this study include weighing at least once a week, biochemistry (neuropathy target esterase, acetylcholinesterase) and, at least, and detailed observations, as well as gross necropsy and histopathology. The findings of this study should be evaluated in terms of the incidence, severity, and correlation of behavioral, biochemical and histopathological effects and any other observed effects in each of the treated and control groups.
This Test Guidelines describes several methods and devices to determine the temperature or temperature range of the phase transition from the solid to the liquid state or from the liquid to the solid state.
The melting point is defined as the temperature at which the phase transition from the solid to the liquid state at atmospheric pressure takes place. It is considerably affected by impurities. The selection of a particular method depends mainly on the state of physical aggregation of the sample and on whether or not the substance can be pulverized easily, with difficulty, or not at all. The methods are: the capillary/liquid bath, the capillary/metal block, the Kofler hot bar, the melt microscope, the differential thermal analysis and differential scanning calorimetry, the freezing temperature and the pour point.
This Test Guideline describes a method to determine experimentally Pow values in the range log Pow between -2 and 4 (occasionally up to 5). This method can not be used with surface-active materials. The partition coefficient is defined as the ratio of the equilibrium concentrations of a dissolved substance in a two-phase system consisting of two largely immiscible solvents.
The test should be done at a temperature in the range 20 to 25°C, kept constant at ± 1°. There are three runs with different volumes ratio of n-octanol to water. Duplicate vessels containing accurately measured amounts of the two solvents and stock solution are used in all three runs. After agitation the separation of the two phases, in general, is achieved by centrifugation. It is necessary to determine the concentrations of the test substance in both phases. Analytical methods which may be appropriate are: photometry, gas chromatography and high performance liquid chromatography. The total quantity of substance present in both phases should be calculated and compared with the quantity originally introduced. A Pow value is calculated from the data of each run. The six log Pow values should fall within a range of ± 0.3 units.
This Test Guideline describes methods to determine the surface tension (in N/m) of aqueous solutions. The methods are based on the measurement of the force which it is necessary to exert vertically on a stirrup or ring, in contact with the surface of the liquid, in order to separate it from the surface, or on a plate, with an edge in contact with the surface, in order to draw up the film that has formed.
There are four different methods: the plate method, the stirrup method, the ring method and the OECD harmonized ring method. They are described in detail in the ISO Standard 304-1985. The methods described are applicable to aqueous solutions of most substances regardless of their degree of purity. The concentration should be 90% of the saturation solubility, but must below 1g/l. This shall therefore be carried out under a protective cover to avoid interference at 20°C approximately. The ring is immersed below the surface of the solution. Then the table top, where the measurement vessel is placed, is lowered gradually and evenly at a rate of approximately 0.5 cm/min to detach the ring from the surface until the maximum force is reached. The force is read on the tensiometer. After completing the first measurement, measurements are repeated until a constant surface tension value is reached.The test substance is administered orally in a single dose to domestic hens. The animals are observed for 21 days, then the remainder of the hens are killed and histopathological examination is undertaken.
The young adult domestic laying hen (Gallus gallus domesticus), aged 8 to 12 months, is recommended. The single dosing with the test substance should normally be by the oral route using gavage, gelatine capsules, or a comparable method. The treatment group should contain, at least 12 hens, and the positive control group at least 6 hens. The objective of the preliminary study is to maximize the main study dose. The limit test corresponds to one dose level of at least 2000 mg/kg body weight/day. The dose level of the main study should be high as possible taking into account the results of preliminary study and the maximum dose level (2000 mg/kg bw/d). The results of this study include measurements (weighing), biochemistry (neuropathy target esterase) and, at least, daily and detailed observations, as well as gross necropsy and histopathology. The findings of this study should be evaluated in terms of the incidence, severity, and correlation of behavioral, biochemical and histopathological effects and any other observed effects in the treated and control groups.
This Test Guideline describes methods to determine the water solubility of test substances. The water solubility of a substance is the saturation mass concentration of the substance in water at a given temperature. This guideline addresses the determination of the solubility in water of essentially pure substances which are stable in water and not volatile. Before determining water solubility, it is useful to have some preliminary information on the substance, like structural formula, vapour pressure, dissociation constant and hydrolysis as a function of pH.
The column elution method and the flask method which cover respectively solubilities below and above 10-2 g/l are described. The test is preferably run at 20 ± 0,5 °C. A simple preliminary test is allowed to determine approximately the appropriate amount of sample to be used in the final test, as well as the time necessary to achieve saturation.