Diferencias observadas en la diferenciación neuronal y astroglial entre las NSC de

6 Discusión

6.3 Diferencias observadas en la diferenciación neuronal y astroglial entre las NSC de

additives Material(s) (usually chemical products) added to change the existing properties of, or impart new characteristics to, aviation fuels (e.g. fuel system icing inhibitor (FSII), static dissipater additive (SDA) etc.).

adventitious materials

solid or liquid contaminants that can be picked up by aviation fuels during storage and handling (including in refineries), and distribution. Examples are rust, dirt, free (undissolved) water, salt and microbiological growth. Unlike incidental materials (see

below), which are homogeneous, adventitious materials are heterogeneous, and can be removed from aviation fuels by appropriate settling and filtration/separation.

approved additives Additives that have been approved for use in aviation fuels.

NOTE: Fuel additives can only be listed in fuel specifications after they have been approved by the aircraft and engine OEMs following evaluation under ASTM D4054 Standard practice for qualification and approval of new aviation turbine fuels and fuel additives.

Ap pearanc e Check A field check to confirm the acceptability of the fuel (i.e. the correct colour and that it is visually clear, bright and free from particulate matter and undissolved water at ambient

temperature).

Au th oris ed signatory

See Annex B.

banking system (pipeline)

A process of delivering fuel complying with the reference

specification, which is of the same volume as that received by the pipeline operator, but not necessarily the same batch. Note: Such systems are not necessarily fungible.

batch; batched material

an identifiable quantity, produced at a refinery, tested and

identified as a single entity. If product from two or more batches is mixed within or downstream of the refinery, it is tested and re-identified as a new batch. (See also certified material)

batch tank A tank in a refinery or supply installation in which fuel can be batched.

bio component Material derived from plant or animal sources, used as a blending component to produce biofuel; most commonly biodiesel fuel with Fatty Acid Methyl Esters (FAME) or gasoline with ethanol. Not to be confused with biojet

biojet Synthetic jet fuel blend containing synthetic hydrocarbons

produced by hydroprocessing of materials derived from plant or animal sources (e.g. HEFA). Note: “biojet” is more of a marketing term than an accepted technical definition.

bonding The physical connection of two metal objects by an electrical conductor that equalises the charge or electrical potential

between the two objects. Example: connecting a bonding cable between a bridger/RTW and the loading rack before filling.

bottom sample A sample obtained from the material on the bottom surface of a tank or container at its lowest point (Note: this has to be drawn using a dedicated bottom sampler; it cannot be drawn using a conventional sampler).

bridger Road tank truck used to supply aviation fuel from one storage area to another, such as refinery to terminal or terminal to airport.

calibration Set of operations which establish, under specified conditions, the relationship between the values indicated by a measuring device and the corresponding known values obtained using a traceable reference measurement standard with a defined measurement uncertainty.

cathodic protection or cathodically protected

A method of preventing or reducing corrosion to a metal surface (by using an impressed direct current or attaching sacrificial anodes).

Certif icate of An aly sis(CoA)

A document which shows the applicable specification

requirements of the product tested, the date, the test methods followed and the test results. It also includes the quantity of the batch, the batch number, the number of the tank containing the product and references of the RCQs of the different batches comingled in the batch being certified by t he CoA (traceability).

The CoA is required to be signed by designated personnel. Note:

CoAs are valid for 180 days (or 12 months for drummed stocks).

A CoA is raised whenever a full specification test is performed downstream of the original refinery tanks.

Certif icate of Quality (CoQ)

See Refinery Certif icate of Quality (RCQ)

certified material Defined quantity of fuel that has been batched, tested and where a certificate (Refinery Certificate of Quality (RCQ), Certificate of Analysis (CoA) or Recertification Test Certificate (RTC)) has been

issued.

chemical water detector

A device used to confirm the presence of free or suspended water in jet fuel (e.g. Hydrokit, Shell Water Detector etc.).

Chemical water detectors are designed to give a positive

indication of water in fuel at concentrations of above 30 parts per million.

clay t reater A treater that uses the medium of a special Attapulgus clay, either in bulk or in replaceable cartridges, to adsorb and pick up surface active agents, colour bodies and very fine particles in the fuel, not otherwise removable. (Clay treaters are sometimes erroneously referred to as clay filters)

colour In aviation gasolines, colour relates to the appearance of the product compared with the expected colour, e.g. Avgas Grade 100LL is dyed blue and therefore is checked against this known standard for product identification.

For jet fuel, Saybolt colour, a defined quality parameter, is tested using ASTM D156. Saybolt colour detects depth of colour, not tint.

comingle, comingling

The mixing of the same product grade from two or more different sources or batches.

compartment A liquid-tight division in a cargo tank.

competent person A person who has documented capabilities and has the experience in the relevant areas.

contaminated fuel Fuel that has been contaminated by adventitious or incidental materials in excess of specified limits, or by mixture with other fuels.

contamination Foreign matter, solid or liquid, which gets into any aviation product, e.g., water, rust, dirt, another product grade, etc. (See also adventitious and incidental material).

Control Check The Control Check consists of an Ap pearance Check plus density determination.

copper strip corrosion test

An analytical test to assess the relative degree of corrosivity of a fuel.

custody transfer An event where fuel passes from one entity/operator to another.

Custody transfer poi nt (CTP)

The point where responsibility for fuel quality changes from one party to another, e.g. a defined point between a terminal

transferring fuel to a pipeline operator, or from the pipeline operator to a receiving terminal. The CTP has to be agreed between the parties involved.

dedicated The use of equipment for carrying and storing only a single grade of product. For tanks, vessels, tank trucks, tank containers and rail cars, dedicated means that at least the previous two cargoes have been the same product as the one being loaded/stored and change of grade procedures have been followed. See

segregated.

diff erential pressure The difference in pressure readings between the inlet and outlet sides of a filter vessel. Often referred to as Delta P, DP or ∆P.

dipstick A graduated rod or stick that is inserted into a tank to measure the amount of product in the tank.

direct delivery Where a storage installation delivers directly to an airport facility, via e.g. a dedicated truck, rail, pipeline or barge system (cf . indirect delivery)

distillation The process of separating the components of a liquid mixture by boiling the liquid and then recondensing the resulting vapour.

drain line sample Samples obtained from the water draw-off or drain point of a storage tank, vehicle tank or filter vessel.

Existent gum a non-volatile residue left following evaporation of the fuel.

FAME Fatty Acid Methyl Ester, derived from plant or animal materials, used as a blending component to produce biodiesel. May be present at ppm levels in jet fuel as an Incidental Material.

fast flush Refers to an effective water draw-off from storage tanks.

filter/coalescer element

An element that contains a porous media through which fuel is passed to remove free water by causing very small droplets of water to form larger drops (coalesce) which separate from fuel by gravity. Typically made from fibre-glass. Coalescers also contain pleated filter media for the removal of fine particulate matter.

filt er elements Generic term given to ‘disposable’ separation media installed in filter vessels (i.e. filter/coalescers, separators and microfilters) in order to remove suspended water and particulate matter.

filt er membrane test See Millipore.

filter/water separator

A vessel that contains filter/coalescer elements to remove solid particulate matter and to coalesce fine water droplets, and separator elements to prevent coalesced water droplets from passing downstream of the vessel. Free water from the fuel collects in the sump of the vessel from where it has to be periodically drained.

flash point The lowest temperature at which a liquid or a solid gives off enough vapour to form a flammable air vapour mixture near its surface.

floating suction Suction pipe that floats on the top of liquid in a tank permitting product withdrawal from the top layer of liquid, which directionally is the cleanest and driest fuel in the tank at the time.

free water Any undissolved water in fuel; generally in finely dispersed

droplets that may cause cloudiness and may settle due to gravity, and form a defined layer at the bottom of a container, or in larger quantities as bulk water.

freezing point the fuel temperature at which solid hydrocarbon crystals, formed on cooling, disappear when the temperature of the fuel is allowed to rise under speciﬁed conditions of test. Sometimes referred to as “freeze point”.

Note: This is an aviation-specific definition. The ‘normal’ definition is the temperature at which a liquid becomes a solid, at normal atmospheric pressure.

fuel system icing inhibitor (FSII)

Approved chemical added to fuel to prevent formation of ice crystals in fuel upon cooling.

fungible pipeline system

Fungible pipeline systems are those that transport products co-mingled with other quantities of product meeting the same product specification.

gravimetric test A membrane filtration test using two pre-weighed filter

membranes to allow a quantitative assessment of particulate in the fuel.

hazardo us area classification

A system of classification for equipment to determine requirements for equipment operation in the presence of

flammable vapours etc. e.g. in Europe ATEX. (See intrinsically safe.)

Hydrokit A ‘go-no-go’ test using a chemical powder to detect greater than about 30 ppm free water in jet fuel.

incident An occurrence which affects or could affect the safety of operations.

incid ental materials Chemicals and compositions that can occur in aviation fuels as a result of refinery production, processing, distribution, or storage.

Examples are refinery process chemicals, FAME (biodiesel), and copper or other metals in soluble form. They differ from

adventitious materials (see above) in that, once in the fuel, they are homogeneous and cannot be easily removed. In refinery processing (and in multi-product distribution systems),

contamination of aviation fuel with trace levels of incidental materials is unavoidable from a practical point of view.

indirect delivery Where a refinery or terminal delivers to an intermediate storage installation (cf . direct delivery).

inspector/surveyor A trained, competent person who conducts inspections, surveys or examinations of fuel movements to assess, monitor and report on their quality and quantity.

interface cut A procedure used to isolate or segregate one product from another at the receiving end of a non-dedicated pipeline, as the products go into tankage.

intermediate terminal/storage

A storage terminal or plant situated between the supplying refinery and the airport operating storage. Also includes receipt storage at an airport from which fuel is transferred to airport operating tanks.

inter-product contamination

(cross-contamination)

Another type of fuel contaminating aviation fuel in sufficient quantity to cause measurable effects on the properties of that aviation fuel, or to cause measurable contamination with

incidental materials. For example, a small volume of gasoline in jet fuel can significantly lower its flash point, while contamination

with diesel fuel can raise its freezing point. Contamination with biodiesel can raise the FAME content in jet fuel over the

acceptable limit.

intrinsically safe Equipment and wiring that is incapable of releasing sufficient electrical or thermal energy under normal or abnormal conditions to cause ignition of a flammable atmosphere in its most easily ignited concentration. See hazardous area classific ation.

ISO tank c ontainer A steel container (usually cylindrical with hemispherical ends) installed within a standard ISO frame (normal dimensions 20 x 8 x 8.5 feet), used for the transport of bulk liquids. Most common tank capacity is 25,000L (6,600 USG)

isolation A physical means of separating equipment containing different grades of fuel or certified and uncertified aviation fuel grades.

(See segregation.)

leak Any loss of fuel due to a defect in the storage, piping, or delivery system.

line sample A sample obtained from a line sampling point, drawn while the product is flowing. Not to be confused with Running sample.

low point -(designated)

A drain point in a pipeline where significant quantities of

particulate/water would accumulate if the position was not flushed on a regular basis.

Note: The frequency of flushing should be determined by documented experience. Where pipelines are in turbulent flow conditions, it is unlikely that significant quantities of

particulate/water will accumulate (it is recommended to operate pipelines as close as possible to the nominal flow rate).

lower sample A sample obtained from the middle depth of the lower third of the tank contents

Manufacture/

manufacturer

The word “manufacture” normally applies to the refinery

production of aviation fuels from conventional sources (crude oil, natural gas liquid condensates, heavy oil, shale oil and t ar sands) using conventional refinery processes (see chapter 6). In the context of ASTM D7566, the word “manufacture” is used to refer to the blending of synthetic and conventional fuel components to produce a synthetic fuel blend (also referred to as semi-synthetic jet fuel). (See chapter 11)

master meter A certified accurate meter used to check flow meters on dispensing equipment or fixed facilities.

Mesh strainer A woven metal filter. Coarse strainers are used in pipework to protect pumps, meters, etc. from debris within the pipe that could damage them. Fine mesh strainers are used for product quality purposes to filter out rust, pipescale, etc. from the fuel.

Microfilter, (micronic filter)

A filter specifically designed to remove only dirt particles from a fuel stream. Typically used upstream of Filter/water Separators (FWS) in high dirt environments to prolong life of the FWS elements.

microfiltration Filtration systems that comply with the requirements of EI 1581 5^th edition, EI 1583 6^th edition or EI 1590 2^nd edition.

Micro-separometer (MSEP)

A test method for determining water separation characteristics of jet fuel.

middle sample A sample obtained from the middle depth of the tank contents Millipore A test for solid contaminant in a sample of fuel that is passed

through a filter membrane, which is then weighed (Gravimetric Test), or matched to a colour standard (Colorimetric Test) to determine the degree of contamination.

multiple-tank

composite sample (ships, barges, etc)

A mixture of individual Composite Samples from several

compartments each of which contains the same grade of product.

The mixture is blended in proportion to the volume of material in each compartment.

multi-product pipeline (MPPL)

Pipeline system transporting different qualities of product,

corresponding to different specifications, with or without physical separation between products

non-dedicated A system of tankage, pipes, vehicles, etc., in which more than one product or grade of product can or does flow through the same system; single valve isolation is considered non-dedicated.

Also referred to as a multi-product system.

non-fungible system (pipeline)

When the original identity of each batch will be maintained and the parcels transported in a segregated manner

parcel Discrete defined volume of fuel in a pipeline

particulates Solid contaminants found in Jet fuel (i.e., dirt, rust, sand, fibres, microbial growth); see also adventitious materials

Periodi c Test A selected set of tests carried out on samples of static stock after 6 months to confirm that fuel meets the relevant specification and that the quality of the fuel has not changed significantly since the last test was carried out. The Periodic Test is the same as a Recertification Test with the addition of a thermal stability test requirement.

Positive segregation A means of providing more effective isolation than that provided by single valve separation (which can leak). Examples are double block and bleed valve; spectacle blinds, spades or equivalent; or removable distance pieces like spools or flanges. See also

segregation

POZ-T A chemical water detector and dirt contamination device

produced in Russia and approved by JIG/IATA for use. Similar to Hydrokit and Shell Water Detector, but with an additional dirt contamination indicator.

pressure, operating The pressure against a pump’s maximum no-flow head, existing in a system under flowing conditions or static conditions but excluding surge pressures.

pressure, test The pressure at which a system or a component of the system is tested to verify its integrity.

prover tank A volumetrically calibrated tank used to prove the accuracy of the meters. Also called meter proving tank or calibration tank.

qualification Demonstrated skill, documented training, demonstrated

knowledge, and experience required for personnel to properly perform the duties of a specific job.

rebatching The process of comingling different batches in a single volume and retesting as a single entity.

Recertifi cation Test A selected set of tests carried out on fuel supplied during or after certain types of movement, to verify that the fuel has not been contaminated and that the quality of the fuel concerned has not otherwise changed. Samples tested are required to remain within the specification limits. Test results for specified critical properties are also required to be within maximum variances of the previous analysis of the same fuel batch. Implicit in the definition of

Recertification Test is the comparison of the results with those on the original RCQ or CoA.

reconciliation Comparison of the quantity of additive used with the volume of fuel additivated to verify the dosage rate.

Refinery Certif icate of Quality (RCQ) (Certificate of Quality (CoQ))

A document which shows the applicable specification

requirements for the products being tested, the date, the test method and the test results. It also includes the amount and type of additives used, the quantity of the batch, the batch number and the number of the tank containing the product. The RCQ is

required to be signed by designated personnel. Note: RCQs are valid for 180 days (or 12 months for drummed stocks). A RCQ is raised whenever full certification tests are performed at a refinery.

Note: sometimes also referred to as Refinery Batch Test Certificate.

relaxation time The time required to allow any build-up of static electricity within the fuel to dissipate. This is calculated by including volumetric capacity in a fuel handling system, which increases the residence time (downstream of any charge generating equipment such as filters) for the purpose of dissipating, or losing, static electricity charge, before the fuel discharges from the fuel system into a tank, truck or aircraft.

Release Certi fic ate A document that supports any transfer of aviation fuel, confirming compliance with the applicable specification and containing, as a minimum: reference to batch number or other unique identifier (e.g. tank number, date and time), test report number (last full certification - RCQ or CoA or re-certification test on this batch), date and time of release, certified batch density, quantity of fuel (this may be added subsequently for pipeline transfers),

compliance with the visual appearance requirement (and

conductivity if SDA is present), grade of fuel and specification, signature of releasing authority.

rundown tank A tank in a refinery receiving product direct from a processing

In document Generación de iPSC como modelo de estudio de enfermedades mitocondriales causadas por mutaciones en GFM1 y POLG (página 146-153)