" article about ultraviolet water disinfection. Earlier, we talked mainly about water disinfection using ultrafiltration (a type of membrane water filtration). And, touching on the topic of ultraviolet sterilization, they spoke about it not very well (they say it is not as economical and beautiful as ultrafiltration). However, nevertheless, most sterilization systems today are based on ultraviolet light. We will talk about the reasons for this phenomenon.

About ultraviolet disinfection of water, it is worth starting a conversation with the basics - with ultraviolet radiation as such. Ultraviolet radiation is a type of electromagnetic radiation (like visible light) that lies between the violet border of visible light and X-rays. That is, ultraviolet radiation has a fairly wide range.

In the picture, this range (namely, wavelengths from 400 to 10 nm) can be demonstrated as follows:

Accordingly, the question arises - what is so bactericidal in ultraviolet radiation? After all, purple light is harmless (it seems). And X-ray radiation is associated with gamma particles and a nuclear explosion ... We do not kill bacteria with radiation, do we?

Well, let's answer this question.

But first, a note about the units of measurement of ultraviolet radiation - nanometers:

Nanometer (nm, nm) is a unit of length in the metric system, equal to one billionth of a meter (i.e. 10−9 meters).

So, many have heard that radio waves come in different lengths - meter, kilometer, centimeter. So, we can say that ultraviolet radiation is nanometer radio waves. By itself, ultraviolet radiation can be divided into several groups. So, this is:

1. Near ultraviolet (UV-A): wavelengths 400-315 nm
2. Medium ultraviolet (UV-B) - wavelengths 314-280 nm.
3. Far - wavelengths (UV-C): 280-100 nm
4. Extreme ultraviolet. Wavelengths 100-10 nm.

The near ultraviolet range is often referred to as "black light" because it is not recognizable by the human eye, but when reflected from some materials, the spectrum goes into the visible radiation region. For the far and extreme range, the term "vacuum" is often used, in view of the fact that waves in this range are strongly absorbed by the Earth's atmosphere.

An interesting fact that is not related to our topic:

Ultraviolet radiation is practically imperceptible to the human eye, but with intense exposure it causes a typical radiation injury (retinal burn). Soft ultraviolet (300-380 nm) is perceived by the retina as a weak violet or grayish-blue light, but is almost completely retained by the lens, especially in middle-aged and elderly people. Patients implanted with early artificial lenses began to see ultraviolet light; modern samples of artificial lenses do not let ultraviolet through.

So back to ultraviolet disinfection of water.

Radiation with a wavelength of 320-400 nm ( near ultraviolet) reacts with oxygen dissolved in water to produce highly reactive oxygen species (oxygen free radicals and hydrogen peroxide) that can destroy pathogenic organisms. In addition, it has been found that sunlight is detrimental to microorganisms contained in drinking water, in particular because ultraviolet radiation ( medium ultraviolet) directly affects the metabolism and destroys the cellular structure of bacteria.

It has been found that at a water temperature of about 30 °C (86 °F) and a solar radiation threshold of at least 500 W/m2 (full spectrum), about 6 hours of exposure is required to achieve an effect. This corresponds to approximately 6 hours of processing at mid-latitudes on a sunny summer day.

So, the near ultraviolet is the "safe" ultraviolet, to which we are all quite accustomed. This ultraviolet gives us a tan, vitamin D and can cause sunburn. Medium ultraviolet can disinfect water, but this requires at least 6 hours of exposure to the sun.

So something else is needed to disinfect water on an industrial scale - far ultraviolet. So, for disinfection of water on an industrial scale, manufacturers try to ensure that at least 86% of the radiation falls on a wavelength of 254 nm. That is, in the middle of the far ultraviolet. The reason for this is that ultraviolet with a given wavelength passes well through many substances (for example, through the shells of bacteria) and is absorbed by the DNA and RNA molecules themselves of bacteria. Well, the absorption of ultraviolet radiation in large doses leads to impaired functioning.

In the case of bacteria, DNA-RNA synthesis is disrupted (UV radiation at these wavelengths causes thymine dimerization in DNA molecules), which leads to the accumulation of mutations and, in turn, leads to a slowdown in the rate of reproduction of bacteria and their extinction. What we need!

Highlights of the use of ultraviolet water disinfection.

Size and type of organism. Theoretically, ultraviolet radiation can kill viruses, bacteria, fungi and protozoa. In practice, large organisms such as protozoa may require a higher dose of radiation. Much also depends on the type of organism: some bacteria are more resistant to radiation than others.

UV lamp power. The amount of ultraviolet produced directly depends on the power of the lamp itself. The more powerful the lamp, the more UV it produces. Unfortunately, the ability of lamps to produce UV rays decreases over time, so lamps need to be replaced every 4-6 months. The optimal temperature for producing ultraviolet light is from 40 to 43 "C. In a colder environment, the productivity of sterilizers decreases.

Penetrating power of ultraviolet radiation. Ultraviolet rays are able to penetrate through water. However, the greater the density of water, the lower their penetrating power. If UV rays are not able to penetrate to depth (through water), then there is little sense from them. muddy water also reduce the productivity of the plant. UV sterilizers should be placed after water filters. Otherwise, bacteria, simply put, hide in the shadows cast by mechanical impurities. And calmly wait for the cessation of exposure to ultraviolet radiation.

There is also a moment salinity: in fresh water the penetrating power of UV rays is higher than in salt water. That is, the higher the salt content in your water, the worse the UV lamp will work.

And finally, important cleanliness of the lamp and its shell. If the lamp or shell is covered with limescale, it will simply block the radiation. And he begins to cover the lamp in hard water from the moment it is turned on. Therefore, the lamp must be regularly cleaned of limescale with citric acid.

In addition, this means that the UV lamp when replacing IT IS FORBIDDEN grab the glass with your hands. Left fingerprints reduce the effect of ultraviolet disinfection of water.

Working hours sterilizer. How more water exposed to UV radiation, the more harmful microorganisms die. The contact time is also often referred to as the "hold" time. The holding time depends on the water flow. The lower the flow rate, the more time contact. The length of the lamp also has an effect. With a long lamp, the time of contact of water with the sterilizer increases.

Processed water temperature. UV rays travel best in 40-43"C water. So if you're sterilizing ice water straight from the well - this is not the same as if you decide to sterilize already heated water.

• the lamp must be clean;
• water must be clear;
• it is necessary to disinfect soft water (so that there is no limescale);
• there should be no dissolved iron in the water (so that the turbidity of the water does not decrease);
• water should be warm;
• the lamp should be as long as possible;
• the water velocity should be as low as possible
• the lamp must be changed regularly (since the longer the lamp works, the worse it emits ultraviolet radiation);
• the lamp should be as powerful as possible;
• water should be as salty as possible;
• there should be no bacteria in the water 🙂

So even if your funds allow you to install only a tiny UV lamp on the faucet drinking water- it's not scary, because you know how to increase the efficiency of water disinfection with this lamp.

By the way, we said earlier that ultraviolet water sterilizers are more common than the less whimsical and less expensive ultrafiltration membrane to operate. The reason for this phenomenon is the price of the issue. UV lamps are cheaper - especially if their cost does not include the cost (in order to prevent the formation of limescale) and mechanical water treatment.

Thus, ultraviolet water disinfection is a good option to protect against a variety of bacteria.

According to http://www.zooclub.ru/aqua/233.shtml and Wikipedia

Would you like to surprise your friends or guests on house party? Now, in order to do this, it will not take almost any effort. Magic UFO Magic UFO will do all the work for you, allowing you to captivate the attention of everyone around you with your fantastic telekinesis abilities! The mystical UFO of bright silvery color hovering among the guests will not leave indifferent either adults or children, forcing them to follow the movements of your hands as if spellbound.

This magical device does not require batteries or a remote control. The Magic UFO makes absolutely no sound during its flight. It is very easy to operate and suitable even for children aged 8-9 years. It is enough to throw the UFO into the air like a Frisbee, spin it in the air or take it with your fingers from above and spin it like a top, after which the toy will take on a state of flight, the direction of which you can control from a distance!

But, like all magic tricks in the world, the flight of a magical UFO is nothing but an illusion. In addition to the Magic UFO itself, the package also includes a cardboard spool with 15 thin threads wound around it, made of a special Pixie Silk material and woven into a single large thread. Both ends of this large thread are attached to the spool with a small piece of plasticine. Threads-fishing lines and plasticine are integral parts of the magical UFO, without which its flight is simply impossible. Therefore, be careful and in no case do not lose the spool of plasticine and do not tangle the threads with each other.

Now let's take a closer look at the process of preparing your UFO for its use:

1) Gently unwind the large thread, consisting of 15 strings, into one straight line.

2) Pull out one line from the large thread, you will need it to play with the Magic UFO. The rest of the threads are spare.

3) Separate a small part from a piece of plasticine and roll a small ball out of it, about 4 mm in diameter.

4) Wrap one end of the thread around the plasticine ball, making 4-5 turns, then flatten the ball with your fingers, fastening the thread to the plasticine as well as possible.

5) Place the end of the thread with plasticine under the upper shiny part of the Magic UFO, in the center of which there is a special slot, ending with a small round hole in the middle of the toy, through which you need to bring the thread up.

6) Fasten the other end of the fishing line to your clothes, for example, on the top button of your shirt, tying the thread to it with two knots. You can also fasten the thread to a pin and then also attach it to your clothes. After that, the UFO will hang right in front of you on an invisible thread-line.

7) Move the thread away from you with one hand, passing it between your index finger and thumb. Grab the top of the Magic UFO with your other hand and spin it like a top.

8) After the toy begins to rotate, move the thread away from you and bring it closer, imperceptibly shifting it from one hand to the other.

A few workouts will be enough to learn how to operate the Magic UFO like a real master from popular videos on the Internet. Conquer your friends, relatives and people just unfamiliar with the magic of your hands by ordering a Magic UFO toy right now!

A wide variety of UV lamp options are available on the market today. This allows buyers to focus on the relatively low cost of such goods. Despite the availability, it is always necessary to be interested in the power indicators and additional features of the purchased devices. for home use can be collected independently if there is no desire to part with money.

Ultraviolet

Segments of the electromagnetic spectrum of high energy power are called ultraviolet. Exist different types radiation. The ultraviolet spectrum is divided into three main groups according to wavelength. UVC rays pose a danger to living beings, the wavelength range is 180-290 nm. UVB - vital for reptiles, medium range - 290-320 nm. UVA - long wave, 320-400 nm.

Varieties of ultraviolet lamps

UV lighting elements vary in length, spectrum, power, and shape. They are available in the form of tubes, incandescent lamps or metal vapor lighting fixtures. Due to the variety of characteristics, the list of possibilities for using ultraviolet sources is expanding. All devices have a different working distance. The length of the product always corresponds to its power.

Creating an ultraviolet lamp

DRL 250 consists of several shells. External protective layer does not pass ultraviolet. This shell must be carefully broken so that the inner part is not damaged. For example, you can wrap a light bulb in a wet rag and clamp it in a vise. The outer shell will burst, unable to withstand the pressure. What is found inside is treated with an alcohol-based solution.

A 30W bactericidal lamp in a store costs from 300 rubles, and a 250W DRL-250 lamp costs only 100. A larger volume is being processed. Such an ultraviolet lamp for home use is cheaper and more efficient.

Another cleaning lamp

To achieve the same goals, you can resort to another solution. A non-polar high voltage capacitor can be used as a current limiter. You also need to turn it on sequentially. As protective coating you can use a cut bottle. The ultraviolet home lamp is fixed in its upper part. The gap between the walls and the plinth is filled with electrical tape. The remarkable ultra-violet emitter is ready for high-quality sanitary processing of rooms.

In addition to cleaning basements, such lamps can be used to create artificial lighting. cultivated plants. Just before use, be sure to find out about all the conditions and possible consequences use of this type of device for such purposes. Plants need to be fed according to correct proportions, formed by optimal indicators of light intensity and duration.

From the history of DRL-250

DRL-250 burners were used in the processing of memory chips for erasing them. Electric kettle Soviet-made was used as ballast. The process of boiling water in a filled container was used as a reference to determine the completion of the chip erasing procedure. The kettle was used as a timer, while the erasing device was an ordinary ultraviolet lamp. Reviews of experts agree that when as a ballast, the destruction of the electrodes occurs. For this reason, industrial designs are characterized by inductance. Among them there are no capacitive devices.

Conclusion

Ease of use, efficiency and, of course, affordability are typical of today's modern UV lamps. They can be used at home, as well as in various areas of medical practice. Discoveries of the polymerization properties of lacquer have even led to the widespread use of ultraviolet in beauty salons today. Such a device is easy to assemble yourself.

The use of ultraviolet emitters must be authorized by doctors. These items are still medical equipment. Many people may have contraindications to exposure to ultraviolet rays. The operating instructions and the permitted operating mode must always be observed. UV lamps are recommended to buy only in specialty stores, because the characteristics of this type of products define them in the category of medical equipment. The safety and reliability of lighting fixtures can only be guaranteed when purchased from specialized stores.

You may be familiar with the new my mystery ufo . This is a rotating mysterious disk, which is controlled by the power of thought and magnetism. Below is an instruction for such a thing and surprise your friends without paying at least 600 rubles for it (at least my mystery ufo costs so much).

For those who do not know what my mystery ufo is, video:

First you need to download here with instructions and materials, it weighs 1.6Mb.

It has two pages on which the elements my mystery ufo to be printed and cut:

The third page, a page of instructions on what to do and what to do in what order:

Briefly about what needs to be done:

2. Print out (on thick paper)

3. Cut along the contour

4. Glue or staple the parts, according to the instructions

5. In the center we make a thin hole (you can use a needle)

6. We fix one end of the fishing line with a knot on the disk, and the other behind the ear or behind the collar with a knot.

Clickable:

And a video instruction on how to use my mystery ufo:

Such a toy-trinket, surprise everyone with it to your friends, just don’t tell anyone what you found how to do on the site website!

For the inquisitive, an article on how to make a burner at home

An amazing toy based on the energy of the human body. Keeps in the air due to torsion around its axis and due to magnetic field created by man. (Extract from the manufacturer's website).

Everything works on statics and a human magnetic field and costs about ten US dollars, but on our website you can download the drawing absolutely free.

Download…

We have unraveled the secret of the flying saucer and now thanks to our website you can make this wonderful toy yourself.

What you should end up with:

To make you will need:

Download (free) drawing from the link. Printer, preferably color, three sheets thick paper A4 format, scissors, glue or a stapler, a sewing needle or an awl (pierce a hole for the fishing line) and 1.5 m of the thinnest fishing line.

Operating principle:

The principle of operation is outrageously simple. One end of the fishing line is attached to the toy, the other end behind your ear can be glued with a small piece of adhesive tape or a loop can be made. The main condition is that the fishing line is thin and barely noticeable. The length of the fishing line should be such that, tilting its head slightly, the toy hangs about 50-60 centimeters.

Then, in this position, take the toy by the edges with your hands and unwind it clockwise. Quickly intercept the line in the middle by inserting it between the large and index fingers left hand. Moving up and down the line with your hand while the toy is rotating, an illusion of floating in the air is created. The rest is a matter of technique and long training. Download…

And in conclusion, for those who are too lazy to make anything, you have a second option to get this wonderful handmade UFO ...

Buy My Mystery UFO on our website:

The administration of our site can order a flying saucer for you at the lowest price from our Chinese partners. The toy is not much different from the American original, except perhaps at a lower price.

Product photo:

Price:
1 PC. - 300 rubles.
2 pcs. - 500 rubles.

Delivery in Russia for free! When buying 2 pieces, indicate the quantity in the comments and change the amount in the payment field to 500 rubles. We'll send two. If it is needed large quantity there will be a discount. Contact the administration.

Important! Be sure to indicate your First Name, Last Name and Patronymic, also indicate your postal code and address. Please check your details before paying. Delivery time 15-35 days. After payment, you will receive an email with a notification and a tracking number.

Ask questions in the comments, we will definitely answer.