Ask for help What does it mean to not be able to lock the field in MRI

Ask the tester to shim the standard first, and then test your sample after it is homogenized. Do you mean to use deuterium water to shim the field first, and then test it after it is homogenized? Guyunjing (contact ta) went directly to the MRI.

The teacher asked, hahaha guyunjing (contact ta in the station) to divide your sample into purity, the amount given is enough, it's OK! Zhaobinglty (contact ta) locks the field for the following reasons: 1. Make sure that you have a deuterated solvent in the sample tube (even if you use ordinary solvent to dissolve, adding 2 drops of deuterated solvent should also be able to lock the field and conduct testing) 2. The lock file of the instrument is disordered (let the tester re-debug).

I've also had cases where I couldn't lock the lock, but I've only encountered chloroform.

When used as a solvent, heavy water.

It's the first time I've heard of it. Although the current instruments are very advanced, there are still many problems, and you will often encounter the above situation when doing temperature change experiments. Yangjiaoap (station contact ta) sometimes has too many samples, which can also cause this situation, which I have encountered before.

celan (site contact ta) originally posted by zxyhbu at 2011-03-20 16:07:38:

Divide your sample into purification, the amount given is enough, and it's OK! This opinion is debatable.

The impossibility of locking the field in the NMR means that the magnetic field of the NMR instrument cannot be stably maintained in a high vacuum.

The rear seat cannot be locked, which may be caused by the circlip problem of the rear seat locking of the car, and it is recommended to check whether it needs to be replaced.

Or if you can't keep it, you should go and change the lock.

It may be a problem with the buttons, and then it is the way in which the landlord built the answering machine, whether it is welded by the hole board or the breadboard plugged in.

Answer: (14 points in total).

14 Keep looking back Stay for a moment, flash into the door, and don't look back Loneliness (or loneliness, loss) (3 points in total.) 1 point per empty, the meaning is close)

15 Sample Answer: Write about the child's timidity and attachment to the mother on the first day of elementary school, showing the mother's concern for the young child, paving the way for the son to grow up and become independent and drifting away in the later text, and also to lead to the father who grew old and left in the later text. (4 points in total.)

1 point for each point, the meaning is close)

16 Sample Answer: In the text, "eye" has two meanings, one is to see my son's back as he grows up: I watched my son go to an elementary school classroom, go to the United States to go through customs, and go to college to get on the bus.

expressed his concern and reluctance for his son and the loneliness that he could not let go of in the face of his son's growth. One is the back of watching my father grow old and move away: I watched my father send me to the university and leave, my father entered the ward, and finally entered the crematorium.

expresses the pain that cannot be saved in the face of his father's aging. (7 points in total, 2 points for meaning, 4 points for combined text, 1 point for language fluency).

Still have questions.

If you don't understand, please ask.

There will be a gap when the wire EDM machine lock is locked, what is going on? What to do? The three core parts of the wire EDM machine are the bed, the screw and the guide rail. This problem is the detail of the lead screw.

Wire cutting machine tools, generally using computer program control, when we lock the XY axis drive of the machine tool in the processing interface of the operating system, this soft switch can lock the mechanical part of the machine tool in time. Operators who have done wire cutting generally have this experience. When we locked the shaft, we found that the handwheels of the x-axis and y-axis could still shake slightly.

It's what we usually call a gap.

There is a gap in the handwheel, which is generally normal as long as it does not exceed a certain range. In the old Ningbo wire cutting machine before, the crank of each handwheel was 2mm in one circle, but now it is rare, and most of them are 4mm in one circle. Each tick, each square, represents the millimeter.

This is allowed if the gap between the backs and forth does not exceed half a scale.

Reason: Because the lock is rusty and inflexible.

Solution: 1. Wipe the lock surface with a dry cloth.

Soybean oil. Sewing machine oil or sesame oil.

Drop into the keyhole, put a few drops of oil in the keyhole, insert the key into the keyhole, slowly twitch back and forth a few times until it feels smooth, and turn the key to open the key.

After the lock is opened, put a few drops of oil in time, wipe again with a dry cloth and keep it.

2. If there is no oil for the time being, you can use soap or pencil shavings instead, but the effect is slightly similar.

Pour some kerosene into the keyhole.

Because it has the function of dissolving rust and rust dissolving agent (or WD-40), which is the same squeeze spray (with a thin tube to avoid scattering) used to kill mosquitoes, and then sprayed onto the keyhole. Once the rust is dissolved, throw away some of the pencil foam and it will open again.

Reason: Because the lock is rusted and inflexible, the solution: add oil or other lubricating oil at the lock activity to solve this problem.

As shown in the figure below:

1. The buckle is short of oil, 2 cylinders are broken, 3 cylinders are misplaced, and the locks are broken, and they can be locked until they can't be opened.

The buckle is not right, or it has been deformed! Change the lock or fix it.