针对您的滴定应用，您可以在 BRAND 找到带有 Schellbach 标记条的滴定管处、棕色玻璃滴定管、紧凑型滴定管和 Bang 型微量滴定管。欢迎了解更多关于我们的实验室 A 级和 B 级滴定管的信息。
BLAUBRAND® Schellbach Stripe 标记: 主刻度为环形。读取标记条的接触点。SILBERBRAND Schellbach Stripe 标记条: 主刻度为短刻度。读取标记条的接 触点。SILBERBRAND: 主刻度为短刻度。 读取标凹液面的最 低点。
滴定管与自动回零滴定管都是(TD, Ex)校准。 等待时间：BLAUBRAND® — 等待时间30秒。SILBERBRAND — 无等待时间。(注：通常滴定时并不需要等待时间（参见DIN EN ISO 385)。所有BLAUBRAND® 滴定管与自动回零滴定管都随原厂包装提供批号以及批次认证证书。根据要求，也可提供个体检验证书、USP个体检验证书或DAkkS校准证书
PTFE阀芯 操作紧致顺滑，无需润滑，因此不会在滴定管上残留凡士林。阀芯可更换。密封紧致且无阻力 只需轻轻旋转即可关闭滴定阀。高精度滴定头 精准地逐滴控制。液滴大小一致 — 从第一滴至最后一滴。液流断开精确不会粘附于边缘。
Class A and AS refer always to highest quality grade in accord to the respective standards and 'S' stands for swift delivery only used for volumetric instruments calibrated to deliver, pipettes and burettes (TD, Ex). For volumetric instruments calibrated to contain (TC, In) a swift delivery is not necessary and therefore not defined in the respective standards.
In case no Schellbach stripe is imprinted the volume of a concave meniscus has to be read at the lowest point of the liquid level. Here the lowest point of the meniscus has to touch the upper edge of the graduation mark. For parallax-free adjustment of the meniscus, the burette is held upright and the observer's eye must be at the same height as the meniscus. In this position the ring mark will appear as a line. The meniscus will appear darker and more easily readable in front of a light background if a piece of dark paper is held behind the instrument immediately beneath the ring or graduation mark.
No. Even with a slightly broken tip two effects are obtainable: First, the risk of injury to yourself increases. Second, the flow rate changes through the broken tip so that volumes are false and measure uncertainties increase.
Some burettes contain subdivision marks or a kind of glass which are not prescribed in DIN EN ISO 385. Subsequently these burettes do not meet all specifications of the standard, but they meet the error limits according to class B of DIN EN ISO 385.
Squeeze bottle for rapid filling, wait for automatic zeroing, and titrate rough by releasing the micrometer screw and pressing the button, or titrate fine by using the micrometer screw. If these burettes are not in use for longer periods they should be drained and the tubing pressure should be released by opening the stopcock.
PTFE valve spindles operate smoothly without any lubrication. Glass keys should be lubricated very slight to operate smoothly.
The abbreviation Boro 3.3 or 5.4 represents the designated borosilicate glass type 3.3 or 5.4, which is used for manufacturing amber burettes.
No. Typically, the volume used in a titration is less than nominal volume, and the standard solution is added dropwise when close to the color change to avoid overtitration. In practice the time required for this dropwise addition is the same or even longer than the established waiting time of class AS burets.
Attach rubber bellows on glass bottle of modular automatic burette, squeeze rubber bellows for filling, wait for automatic zeroing, and titrate by opening the stopcock.
