1、BRITISH STANDARD BS EN ISO 1741:1995 Dextrose Determination of loss inmass on drying Vacuum oven method The European Standard EN ISO1741:1994 has the status of a BritishStandard UDC 664.162:543.81BSENISO1741:1995 This British Standard, was published underthe authority of the Standards Board and come
2、sintoeffect on 15January1995 BSI 01-2000 The following BSI reference relateto the work on this standard: Draft announced in BSINews, March1993 ISBN 0 580 23176 3 Cooperating organizations The European Committee for Standardization(CEN), under whose supervision this European Standard was prepared, co
3、mprises the national standards organizations of the following countries: Austria Oesterreichisches Normungsinstitut Belgium Institut belge de normalisation Denmark Dansk Standard Finland Suomen Standardisoimisliito, r.y. France Association franaise de normalisation Germany Deutsches Institut fr Norm
4、ung e.V. Greece Hellenic Organization for Standardization Iceland Technological Institute of Iceland Ireland National Standards Authority of Ireland Italy Ente Nazionale Italiano di Unificazione Luxembourg Inspection du Travail et des Mines Netherlands Nederlands Normalisatie-instituut Norway Norges
5、 Standardiseringsforbund Portugal Instituto Portugus da Qualidade Spain Asociacin Espaola de Normalizacin y Certificacin Sweden Standardiseringskommissionen i Sverige Switzerland Association suisse de normalisation UnitedKingdom British Standards Institution Amendments issued since publication Amd.
6、No. Date CommentsBSENISO1741:1995 BSI 01-2000 i Contents Page Cooperating organizations Inside front cover National foreword ii Foreword 2 1 Scope and field of application 3 2 Principle 3 3 Apparatus 3 4 Procedure 3 5 Expression of results 3 6 Test report 3BSENISO1741:1995 ii BSI 01-2000 National fo
7、reword This BritishStandard has been prepared under the direction of the BSI Standards Board and is the English language version of EN ISO1741:1994 Dextrose Determination of loss in mass on drying Vacuum oven method, published by the European Committee for Standardization(CEN). It is identical with
8、ISO1741:1980 Dextrose Determination of loss in mass on drying Vaccum oven method, published by the International Organization for Standardization(ISO). This BritishStandard has been produced to fulfil BSIs obligation to publish all approved European Standards but, because of the absence of interest
9、in the UK in the subject concerned, there has been no UK participation in the preparation of EN ISO1741. Any queries relating to the EN should be directed to BSI. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for
10、 their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theEN ISO title page, pages2 and3 and a back cover. This standard has been updated (s
11、ee copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO1741 August1994 UDC 664.162:543.81 Descriptors: Carbohydrates, glucose, tests, determination, mass losses, dehy
12、dration analysis, stoves(chemistry), low pressure tests English version Dextrose Determination of loss in mass on drying Vacuum oven method (ISO1741:1980) Dextrose cristallis Dtermination de la perte de masse la dessiccation Mthode partuvage sous pression rduite (ISO1741:1980) Dextrose Bestimmung de
13、s Masseverlustes durch Trocknen Vakuumschrank-Verfahren (ISO1741:1980) This European Standard was approved by CEN on1994-08-22. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard
14、 without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions(English, French, German). A version in any other langua
15、ge made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland,
16、Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland andUnited Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1994 Copyright reserved to CEN members Ref
17、.No.ENISO1741:1994EENISO1741:1994 BSI 01-2000 2 Foreword The text of the International Standard ISO1741:1980, prepared by ISO/TC93, Starch, was submitted to the formal vote and was approved by CEN as EN ISO1741:1994 on1994-08-22 without any modifications. This European Standard shall be given the st
18、atus of a national standard, either by publication of and identical text or by endorsement, at the latest by February1995, and conflicting national standards shall be withdrawn at the latest by February1995. According to the CEN/CENELEC Internal Regulations, the following countries are bound to impl
19、ement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, United Kingdom.ENISO1741:1994 BSI 01-2000 3 1 Scope and field of application This International Standard specifie
20、s a vacuum oven method for the determination of the loss in mass on drying of dextrose. The method is applicable to anhydrous dextrose andto dextrose monohydrate. 2 Principle Drying of the test portion in a vacuum oven at100 C, at a pressure not exceeding135mbar 1) . 3 Apparatus 3.1 Analytical balan
21、ce 3.2 Dish, of metal(inert under the test conditions) or of glass, of diameter approximately50mm, provided with a closely fitting lid. 3.3 Electrically heated vacuum oven, capable of being maintained at100 1 C, equipped with a calibrated thermometer and an absolute pressure gauge. The drying oven s
22、hall provide uniform heat distribution and shall maintain the reduced pressure for several hours after the vacuum pumpisturned off. The oven shelves shall be soconstructed and fitted as to ensure good heat transfer to the dishes. 3.4 Vacuum pump, suitable for reducing the pressure in the oven to135m
23、bar or less. 3.5 Drying train, consisting of a drying column filled with dried silica gel; the column is connected in series to a gas scrubber containing concentrated sulphuric acid, which is in turn connected to the air inlet of the drying oven. 3.6 Desiccator, containing an efficient desiccant. 4
24、Procedure 4.1 Preparation of the test sample Mix the sample thoroughly and rapidly by stirring with a spatula in the sample container. If the sample container is too small for this purpose, transfer the entire sample to another pre-dried container of a suitable size to facilitate mixing. 4.2 Prepara
25、tion of the dish Place the open dish(3.2) and its lid in the oven(3.3), controlled at100 C for1h. Allow to cool to room temperature in the desiccator(3.6) and weigh to the nearest0,0002g. 4.3 Test portion Place about10g of anhydrous dextrose or about5g of dextrose monohydrate, in the dish(3.2), fit
26、the lid and weigh to the nearest0,0002g. 4.4 Determination Place the covered dish(3.2) containing the test portion(4.3) in the oven(3.3) maintained at100 1 C, remove the lid and leave it in the oven. Leave at the test temperature for4h, maintaining the pressure in the oven at not more than135mbar. D
27、uring drying, draw a slow stream of air through the drying train(3.5) into the oven. After4h, shut off the vacuum pump(3.4) and allow air to slowly enter the oven through the drying train until atmospheric pressure is obtained. Before withdrawing the dish from the oven, fit the cover. Place the cove
28、red dish in the desiccator (3.6), allow to cool to room temperature, and weigh to the nearest0,0002g. Do not put more than four dishes in the desiccator(3.6) at the same time. Carry out two determinations on the same test sample(4.1). NOTEIf, during or after the test, the material develops a more or
29、 less pronounced yellow colour, repeat the test at a lower temperature, and state this in the test report. 5 Expression of results The loss in mass on drying, expressed as a percentage by mass of the product as received, is equal to where m 0 is the mass, in grams, of the dish and cover(4.2); m 1 is
30、 the mass, in grams, of the dish and cover and the test portion before drying(4.3); m 2 is the mass, in grams, of the dish and cover and the test portion after drying(4.4). Take as the result the arithmetic mean of the two determinations. 6 Test report The test report shall indicate the method used
31、and the result obtained. It shall also mention all operating conditions not specified in this International Standard, or regarded as optional, as well as any circumstances that may have influenced the result. The report shall include all details required for complete identification of the sample. 1)
32、 1mbar=0,1kPa m 1 m 2 () 100 m 1 m 0 -BS ENISO 1741:1995 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incor
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