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@ha91
  • Việt Nam
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  • 05/11/15 09:35:33
    MỌI NGƯỜI GIÚP MÌNH DỊCH ĐOẠN TIẾNG ANH NÀY VỚI Ạ! CẢM ƠN NHIỀU!!!!!!!!!!
    Colorimeter specifications—The instrument consists of a light-proof box with a dull black interior, illuminated by a 100-wattblue frosted electric lightbulb.
    A block of magnesia is placed in the instrument at the proper angle to reflect the light from the electric bulb verticallyupward through the color tube and color glasses. The block must be free from oil and dirt and positioned to give equal illuminationto both...
    MỌI NGƯỜI GIÚP MÌNH DỊCH ĐOẠN TIẾNG ANH NÀY VỚI Ạ! CẢM ƠN NHIỀU!!!!!!!!!!
    Colorimeter specifications—The instrument consists of a light-proof box with a dull black interior, illuminated by a 100-wattblue frosted electric lightbulb.
    A block of magnesia is placed in the instrument at the proper angle to reflect the light from the electric bulb verticallyupward through the color tube and color glasses. The block must be free from oil and dirt and positioned to give equal illuminationto both sides of the viewing field.
    An eye piece finished with a dull black interior is fitted over (outside) the rectangular top of the tube holder so that thelight passes through the color tube and color glasses. Eye pieces with split fields are not permitted.
    The tube holder (2.54 cm i.d. or 1 in. ) is fitted with 30.2 mm (13⁄
    16 in.) i.d. rings at the bottom. One ring is to retainthe color tube containing the oil test sample, and the other is to permit an equal amount of light to reach the color glasses.
    2. Colorimeters—The following colorimeters have been found to be acceptable for use in this method:
    (a) The Wesson colorimeter, constructed as shown in Figure 1.
    (b) The Stevenson colorimeter conforms to the specifications noted in Apparatus, 1 for the Wesson colorimeter and may beused in this method (see References, 1).
    (c) The Lovibond Tintometer model AF 710 (Notes, 1) conforms to the specifications noted in Apparatus, 1 and may beused in this method when operated according to the manufacturer’s instructions. Any subsequent improved model(s), using the same optical principles as the AF 710, may also be used in this method.
    3. Color cabinet—The colorimeter is maintained in a booth or cabinet, not less than 102 cm wide × 76 cm deep (40 in. wide
    × 30 in. deep). The booth or cabinet is closed so that no external light can enter. The inside of the booth is painted a dull, neutral gray of Munsell value 4/.
    The booth or cabinet is indirectly illuminated by means of a bulb and fixture mounted 122 cm (48 in.) above the colorimeterin such a way that no direct light rays strike the colorimeter or the eye of the observer. The level of illumination of the booth (at the top of the box of the colorimeter) should be not less than 1 nor more than 5 foot candles.

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  • 05/11/15 09:27:40
  • Em đang cần dịch tiêu chuẩn AOCS. Anh chị nào giúp em dịch đoạn này ạ. Thanks mọi người nhiều!!!!!!!
    Crude, raw and refined oil test samples must be treated with 0.5 g of diatomaceous earth (filter aid) per 300 g of oil. Add the
    diatomaceous earth to the oil and agitate for 2.5 min at 250 rpm at room temperature (or at no more than 10°C above the
    melting point of the test sample, if it is necessary to maintain the test sample in the liquid state), and filter the test sample
    through...
    Em đang cần dịch tiêu chuẩn AOCS. Anh chị nào giúp em dịch đoạn này ạ. Thanks mọi người nhiều!!!!!!!
    Crude, raw and refined oil test samples must be treated with 0.5 g of diatomaceous earth (filter aid) per 300 g of oil. Add the
    diatomaceous earth to the oil and agitate for 2.5 min at 250 rpm at room temperature (or at no more than 10°C above the
    melting point of the test sample, if it is necessary to maintain the test sample in the liquid state), and filter the test sample
    through an appropriate filter paper (Apparatus, 6). Oils that have been bleached in the laboratory in accordance with AOCS
    Official Methods Cc 8a-52, Cc 8b-52 or CC 8d-55 normally are sufficiently clear for the color determination. Suspended
    material, even if of colloidal size, will cause light scattering. If the test portion is not absolutely clear, treat with diatomaceous
    earth (filter aid) as noted, and filter before proceeding with the color determination.
    2. Adjust the temperature of the test portion to 25–35°C, and fill the color tube to the desired mark. If the test portion is not
    completely liquid at 25–35°C, heat to a temperature of not more than 10°C above the melting point of the test portion.
    3. Place the tube containing the test portion in the colorimeter and place along side of it such red and yellow glasses [see paragraphs
    (a-e) immediately following and Notes, 2] as are necessary to match the color of the oil, observing the test portion of
    the oil and the glasses through the eyepiece.
    (a) Crude and raw oil color—For crude oils of the coconut type, read the color using the proper ratio of yellow to red listed
    below:
    Up to 3.9 red use 6 yellow to 1 red
    4.0 to 4.9 red use 25 yellow to 1 red
    5.0 to 5.9 red use 30 yellow to 1 red
    6.0 to 6.9 red use 35 yellow to 1 red
    7.0 to 7.9 red use 40 yellow to 1 red
    8.0 to 10.9 red use 50 yellow to 1 red
    11.0 to 14.9 red use 70 yellow to 1 red
    15.0 to 19.9 red use 100 yellow to 1 red
    Above 20.0 red use 150 yellow to 1 red
    If the above ratios fail to give a satisfactory match, this fact should be noted and a second reading made using the
    amount of yellow color required for a good match. Report both readings.
    (b) Raw inedible oils—For raw inedible oils (such as tallows, greases, fatty acids, etc.), use the ratios of yellow to red listed
    below:
    Up to 3.5 red use 10 yellow to 1 red
    3.5 to 5.0 red use 35 yellow to 1 red
    Above 5.0 red use 70 yellow to 1 red
    (c) Dark oils—If the color of the oil or fat test sample exceeds 40.0 red when using the regular 133.35 mm column, fill
    another tube to the 25.4 mm mark and read the color under the same conditions as described for the longer column.
    Report the height of the column used, because it is assumed that any color result in which the column height is not
    designated has been determined on a 133.35 mm column.
    (d) Refined oils—For determining refined oil color, use only one yellow glass; 35 yellow for refined cottonseed and refined
    peanut oils, 70 yellow for refined soybean oil. Use not more than two red glasses up to and including 13.0 red, and not
    more than three red glasses above 13.0 red.
    (e) Refined and bleached oils—For refined and bleached oils, the ratios of yellow to red to be used in determining color are
    as follows, except where trading rules specify the yellow and/or red to be used in classifying particular grades:
    Cottonseed, peanut and corn oils—
    Up to 3.5 red use 10 yellow to 1 red
    Above 3.5 red use 35 yellow to 1 red
    Coconut and palm kernel oils—
    Up to 3.9 red use 6 yellow to 1 red
    Above 3.9 red use 10 yellow to 1 red
    Soybean oil—
    Up to 3.5 red use 10 yellow to 1 red
    Above 3.5 red use 70 yellow to 1 red
    Tallows, greases, fatty acids, etc.—
    Up to 3.5 red use 10 yellow to 1 red
    3.5 to 5.0 red use 35 yellow to 1 red
    Above 5.0 red use 70 yellow to 1 red

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    Xem thêm 4 bình luận
    • Năng Lê
      0 · 05/11/15 09:56:27
    • Cuttle
      0 · 05/11/15 09:57:20
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