Many of the performance of detection and analysis instruments are exceptionally sensitive, can determine nanograms of substances detection analyzer even in many laboratories has become a standard testing experimental instrument, syringe filter in the drinking water trace detection and analysis of the role can not be ignored, so how to achieve?
The micro syringe filter is a disposable filter device with a microporous filter membrane between two filter Chambers made of high purity thermoplastics without binder. In the detection and analysis of drinking water metal elements, the microporous membrane can be made of several different materials, such as polyester fiber, cellulose acetate and regenerated cellulose.
The current national standard recommends that the diameter of the pore for filtering insoluble solids is 0.45 micron.In addition to PES polyester fiber with aperture of 0.45 micron and CA regenerated cellulose material filter membrane, RC cellulose acetate filter membrane with aperture of 0.2 micron was also used in the experiment.The filter material can be either polypropylene or acrylic acid copolymer mixture.During the production of the injection-type filter, all parts are automatically inspected in accordance with the standard and the welding quality, pressure resistance and flow performance are finally tested by the quality assurance department.
Why the filter distinction?
1. Subarachnoid injection has high requirements, while epidural injection has lower requirements;
2. The adsorption capacity of fine particles in the liquid on the filter paper is poor, mainly by blocking to filter;In addition to the particles in the air being blocked, the ability to absorb filter paper is also higher.Thus, although the filtration capacity of the filter varies, the filtered liquid and gas may be equally clean.
Why do you have to use a liquid filter?
Because when opening ampoules, the liquid medicine is generally contaminated by glass debris.There's video on the web, and it's very clear with high-speed cameras.
How to use filters correctly?
Liquid filter must be one-way use! Syringe has suction, injection 2 kinds of operation, the filter also has suction filtering, syringe filtering 2 kinds of usage.The filter paper of the filter has two surfaces: suction filter surface and syringe filter surface.If suction is also used, injection is also used, the filter loses its effect.
1. Waist hemp with a blue liquid filter, when the drug is used, when the injection to remove, so easy to use.Because the filter has screw mouth, and lumbar hemp needle connection is not convenient;
2. The epidural with a yellow air filter, inhalation or gas injection can be used, clean the environment without also can.Now that epidural gas injection is not advocated, the filter should be in the near future;
3. The epidural catheter should be connected with a filter, and a blue liquid filter should be used.Unfortunately, the only liquid filter in the lumbago combined anaesthesia bag has been used in the lumbago anesthesia (used when inhaling the drug), can not be used again. A yellow air filter is better than none.I wish I had a liquid filter in the anesthetic bag.
Is the filter one-way? Isn't. Why does it sometimes feel like it's one-way? It's just an illusion.
There are several phenomena:
1. If the suction air, no matter inhaling or injection, the resistance is the same;
2. If only the liquid is pumped, the resistance remains the same whether the drug is inhaled or injected;
3. If the air is sucked after the absorption of the liquid, the resistance will be large first and then small when the air passes through the filter paper;
4. If the liquid is inhaled again, the resistance will become great when the liquid reaches the filter paper (it seems that the filter is one-way at this time), and the resistance will return to the normal size after the liquid passes through the filter paper.
Why is there a one-way phenomenon? This is because there are a lot of tiny bubbles in the filter paper, causing the gas plug to block the filter. After the gas plug is removed, the filter returns to normal.