Ir Definition and 229 Threads

How can you determine the ratio of the keto tautomer of a compound to its enol form? I know which functional groups are associated with which but I have no idea how you'd use an IR spectrum for quantitative analysis like this.

Homework Statement A piece of solid Iron contains 2.5moles of atoms. Whats its mass? suppose one atom in 10^12 were missing one electron, what would be the net charge of the iron? Homework Equations The Attempt at a Solution atomic mass 192.22u so mass should be 2.5*192.22 =...

I keep seeing references to UV and IR in references to string theory and quantum gravity. This seems to come up in discussions of renormalization especially. Can someone please explicitly explain the term? Google doesn't seem to help here. There are way too many references. I have tried...

Unfortunately I have not been able to find anything reasonable online. I'd like an in depth all-inclusive explanation of IR transmitters and receivers, from a physical standpoint. I would also be glad to learn whatever else is included in the reading material, if anything. I have basic...

Hi, I'm trying to design a system which will be able to detect a hot object on a cold surface. The downside is the temperature difference is only 1 degree celcius and I'd like to use IR from a distance of about 10cm (further away preferred if possible). Does anyone with any experience of...

Quantum level working of IR sensor... There are datasheets of IR sensors like the TSOP1738 that conveniently tell me that when I make an IR LED flash at 38Khz, a current is produced. However, i would like to know what happens on an atomic level. Is it just a matter of electron promotion...

Say I want to monitor the interface of an electrochemical cell via IR spectroscopy. If H2 gas is generated, there must be a characteristic IR signature to this event. How can I figure out what this is? Are there calculations for this? I'm sure this is in the literature somewhere, but I...

Hi Why does a bond stretch or vibration have to cause a change in dipole moment to be IR active? Presumably all vibrational modes depend on energy aborption to occur whether they cause a change in dipole or not. I'm presuming that only those vibrational modes that cause a dipole change are...

My bedroom AC has a remote. I would like to make an ultra-simple circuit to duplicate just the ON button. I want to leave the real remote on the nightstand and still be able to turn my AC on from downstairs (I do have line-of-sight). I guess step 1 will be to detext what the remote is sending...

Hi Does anyone know why acetic anhydride has 2 IR bands at 1760 and 1820? If you look it up in a table it says they are due to the 2 carbonyl groups in an anhydride. But this is what I want to know: 1) What specifically is causing the peaks? Is it asymmetric stretching of the carbonyl...

My stereo remote has begun exhibiting strange behaviour. If I use the Power button to turn it on (or off), it will continue to do so for as much as 30 seconds. i.e.: - I point the remote at the stereo and press Power, stereo turns on (the on/off cycle on my stereo takes a good 4-5 seconds)...

Hello all! I'm a sales rep here at << company name removed by moderator>>, we manufacture conformal coating/curing systems. Normally, i'd just ask one of our engineers this question, but production as been shut down for the week as we move to a new facility, so I am out of contact. A...

Using the IR full scan, I have to determine the formula and the structure of the compound. I have attached the scans. Looking at the IR scan, I see that I have an NH and a CH. So is my compound CH2N?? I also have a mass spec output for an unknown organic compound. I have to determine the...

So, I was playing around with remote controls last night and realized that, under the right conditions, I could see a very faint, blinking red glow from the LED that transmits signals to the TV when I held down a button. Looking this up, it appears that most such LED's shine at 940 nm, which is...

Greetings all! I am doing this experiment with my son: http://www.ehow.com/how_2092756_make-infrared-goggles.html" Since IR is a segment of the EM spectrum that human eyes cannot see, how is it that this experiment works? To clarify my question further, since visible light and IR are...

Hey all. I am building an IR modulator but seem to have a small kink in the design. Here is my schematic: Here is a picture of the oscilloscope, connected between ground and the output of the TL555 timer and the output of the second transistor (the output pulse going into the LED's)...

Is there a way to change visible light like the light coming out of the screen you're reading into infrared or any other invisible light and then take that and change it back somewhere else? What I'm what I'm trying to do is make a computer screen or maybe a T.V screen visible to only those who...

Is it be possible to produce from the Intensity return of reflective IR laser the true color of the object causing the reflection of the laser? My though is that surfaces of the same material, but of different colors would cause slight changes in wave length of the laser light. These changes...

Homework Statement Compute the solar irradiance in the near IR range (0.7 - 1.5 microns) at the top of the atmosphere over Denver at noon on August 23rd, and assume that 37 per cent of the solar spectrum is in this range. Homework Equations Equations? I=ScosZ where Z is the azimuth...

1. Compare and interpret the infared spectra of 4-methylcyclohexene and 4-methylcyclohexanol. 2. Identify the C-H out-of-plane bending vibrations in the infared spectrum of 4-methylcyclohexene. What structural information can be obtained from these bands?

Hi guys! I'm a beginning EE students, and haven't taken many courses yet (haven't even covered transistors in my circuits class yet-- we're up to diodes, woo!). For a "for fun" project, I've been messing around with the Arduino microcontroller...

I need a list(data numbers) of short range IR emitter and detector(not very expensive) which can be used as a break beam sensor.. I also like to know what is the specific IC number which is used to tune the IR emitter's frequency which matches with the detectors receiving frequency. I have heard...

Why does a hot object emit Infra red light. How are photons are emitted from it?

Homework Statement Im having a real problem trying to imagine what happens inside the machine can anyone help? I thought that at the interferometer a beam is split into two and then recombined with a path difference to introduce interference. Because the IR source is broadband would all of the...

As aforementioned, I have a L14F1 phototransistor. I am using this in a DC circuit. A stupid question it is. Please take it seriously however. Read carefully; I repeat: how do I make a switch in a DC circuit using a L14F1 (3-pin) phototransistor? And coming to why I don't use a 2-pin...

Where can i get the datasheet? thanks.

Hi all out there. I had recently salvaged an IR bulb from a TV remote (universal). The component I am in search for is an IR switch, that is, completes a circuit only when a signal from an IR LED is received. Could this also otherwise be made with common household stuff? I know that I may get...

At my business we are beginning the design of gas detection systems using IR. My question is what are the benefits of operating solid state IR sources in a pulsed mode?

Homework Statement What is the energy (in kJ/mol) of infrared radiation that has a frequency of 1.614 x 107 MHz? Homework Equations E = nhv The Attempt at a Solution 3 x 6.63 x 10^-34 (J x s) multiplied by 1.614 x 10^7 (MHz) multiplied by (10^6 Hz/1 MHz) multiplied by (1 kJ/ 1000J) =...

Hi, I have 2 questions here and hope some experts can answer them. Question 1: How to improve the signal distance of the IR led?What parameters in the datasheet that we should look into? I have purchased few IR leds but all of them can't shoot more than 3 metres. I noticed increasing...

Hi all, I was struggling in solving this question which is a part of a practice exam, and I need you to be patient with me and teach me step by step how to figure out the structure and how to read and analyze the spectra. I attached the two 1H NMR & IR spectra so you will be able to know...

Homework Statement When a 9.0V - battery is temporarily short-circuited, a 400mA- current flows. What is the internal resistance of the battery? Ans :R_int = 9/(400*10^-3) Can someone explain why this is the answer, I understand its just V/I, but what exactly does this mean? I am...

I am trying to find a gas or liquid that likes to absorb the lower portion of the IR sperctrum (700–1400nm) but let's visible light pass (380-750nm). It can be a liquid or gas because it is going in a sealed container. I know that water absorbs infrared to a certain extent and that's why the...

I am trying to make burglar alarm which is to be triggred whenever someone crosses the IR beam emmited by a IR transmitter circuit. I will place the transmitter in one side of the corridor and reciever on the other site. I want to use TSOP1556 in the reciever module. So any help will be greatly...

These questions relate to an IR Light curtain i am trying to build. The light curtain is going to be used to cut the power to an electrical testing bench when any of the curtains IR light beams are broken. The project will consist of IR transmitters ( IR LED's(zd1946)- data...

Quoting from wikipedia I understand what symmetrical and antisymmetrical stretching come from and the number of vibrational mode(s) can be predicted basing on the concept of degree of freedom. However, for scissoring, rocking, wagging and twisting, are they considered as bending...

question is why speak about IR (short momentum) and UV (short distances) divergences ? in fact if we define \epsilon = 1/\Lambda then both integrals \int_{\epsilon}^{\infty}x^{-k}dx and the \int_{0}^{\Lambda}x^{k-2}dx have the same rate of divergence \Lambda ^{k-1} as...

hey guys I'm trying to build a 38khz transmitter that works about 5m(at least) but its unsuccessful.currently I'm using this circuit. but it can't use more than 50cm. i have no idea how to increase rage. equation is f=1/(0.8*R1*C1) I have some NE555 and a 9V battery some transistors and...

hello i was wandering can i use simple multivibrator circuit to generate 38khz signal to use as a IR transmitter for TSOP1738? i did some readings and calculations and came up with resistor and transistor values that gives 38khz. but since i don't have a oscilloscope i don't know whether...

I am taking my second semester of organic this summer. We are working on IR Spectroscopy and mass spectrometry in class. Is there anywhere that anyone knows about that may put it all together? Or can anyone maybe give me some tips on how to remember all of the main functional groups? I am...

i need help in determining thickness of thin film created by pouring volatime solvent with solute using HATR technique also would like to know how experimental design can be set with HATR technique quantification purpose.

can anybody tell me the difference (terms of specific application) b/w the AR coatings and Interference filters?

Hello all, quick question because this circuit doesn't seem to be working at all... I bought a few IR LEDs to attempt a few of the projects located http://johnnylee.net/projects/wii/" and for some obscure reason none of them are working. I hooked a AAA cell (multimeter rates it at 1.2 V) to a...

Hello I'm currently studying the reaction of anisole with hexacarbonylchromium, and experiment shows the displacement of 2 of the carbonyl ligands with the anisole group, forming a 2-η ligand with the chromium ion. After refluxing to obtain the crystals, IR and nmr spectra of the sample...

Is anybody can give me a detailed explanation or reference why the small bandgap IR detectors (eg. InSb photodetecotr) need to work in the cryogenic temperature? In addition, anybody knows what is carrier capture time? Since some article said the photodetector detectivity is proportional to...

COMSOL RF module: urgent Hi i am a new user to comsol RF module. Actually I a want to model the heating of a material using IR waves... can i use the RF module (which illustrates microwave heating as an example) to model the IR heating...do we have options to change the frequency of wave from...

perhaps is a dumb quetion but, given a IR divergent integral (diverges whenever x tends to 0) \int_{0}^{\infty} \frac{dx}{x^{3}} then using a simple change of variables x=1/u the IR integral becomes an UV divergent integral \int_{0}^{\infty} udu which is an UV divergent...

Here is something that I see every spring, when the sun gets higher in the sky and the temps moderate. Notice the depressions under the raspberry canes... The sun heats up the canes, both above and below (reflection from the snow) and the canes re-radiate IR, melting the snow below them, even...

I'm having problems measuring the temperature of a steel surface with varying emissivity with a pyrometer. So I thought one way to overcome the varying emissivity is to paint the surface with a paint that has a high uniform emissivity in the IR region. The paint should: Have high...

Hi, I'm trying to think up a way to shift IR rays into visible light spectrum so that the human eye can effectively see the IR image. Is it possible to do such a feat with something as simple as goggles made from a special material (e.g. anti-stokes pigments)?? If not possible with such...