Chapter 70: 2 tests

　　 "Why don't you write a review?" Xu Qiu wondered: "Wu Feifei and Duan Yunke both posted a review."
　　 "I want to write too, but my strength doesn't allow it," Chen Wanqing sighed:
　　 "If I write it and publish a Chinese core journal, it is estimated that the English version can only be published in the second-district periodical.
　　 Mainly because Mr. Wei has relatively high requirements for the review, usually it is sent to the first district. He thinks it is better not to write a second district review.
　　 "Dare to ask Senior Sister, have you passed the sixth grade?" Xu Qiu said.
　　 "Of course, I have requirements for English scores in Ph.D. For example, my requirement for a year is 450 points or more in CET-6. I just hit the line, 455 points," Chen Wanqing said:
　　 "I heard that it has risen to 480 points this year. The threshold will definitely be higher and higher in the future. Fortunately, I came early.
　　 By the way, have you prepared the samples for XRD and SEM? You have to test this afternoon. "
　　 "I almost forgot, I haven't prepared yet, how do I prepare the samples?" Xu Qiu said.
　　"The XRD sample is normally coated on the glass sheet, and then in order to prevent the film from deteriorating, it needs to be vacuum sealed and the package is opened before the test.
　　 The SEM sample is also coated on a glass sheet. Use a glass knife to cut the glass sheet from its back, and then break it into two halves to test the section.
　　It is like an organic thin film SEM sample. It needs to be quenched with liquid nitrogen to fix the thin film before breaking. If the perovskite is not used, the sample can be prepared directly. "
　　 The preparation methods of these two samples are relatively simple, Xu Qiu only took less than half an hour to complete.
　　 Among them, the equipment used for vacuum sealing is an electric heating vacuum sealing machine purchased by TB.
　　 Midway, Chen Wanqing went downstairs to make an appointment for the SEM test at 2:30.
　　…………
　　 At about 1:20 in the afternoon, the two went to test XRD as scheduled and came to Room 104 on the second floor of the material.
　　 Teacher Xu Hui is in charge of the instrument, and she also manages the AFM.
　　 Xu Qiu knew her. She was one of the teachers in the "Material Chemistry Experiment" course, but the other party didn't seem to remember him.
　　 They were the first batch of people to test in the afternoon, and no one was testing before.
　　 Therefore, after Chen Wanqing greeted Mr. Xu Hui, he went directly to the test room, installed samples, and prepared for the test.
　　 She asked Feifei Wu about the XRD peak position of the perovskite material in advance, usually between 0-30 degrees, so she set the test angle to 1-30 degrees.
　　 This is because the signal strength between 0-1 degrees is too strong. In order to prevent the detection limit of the detector from being exceeded, the test starts from 1 degree.
　　 XRD equipment only occupies a few square meters, there is a protective cover outside, and the "Beware of Ionizing Radiation" sign is posted on the instrument.
　　 Seeing the equipment here, Xu Qiu said with emotion:
　　 "Compared to the size of the synchrotron radiation source of Magic City, the equipment here is a bit too small."
　　 "Of course, ordinary XRD can only detect small molecule materials with high crystallinity." Chen Wanqing said:
　　"On the light source side, because the brightness of X-rays is more than 100 million times that of this side, even organic polymer materials with only weak crystallization properties can detect their crystallization information."
　　 Xu Qiu nodded, he suddenly had an idea.
　　The simulation laboratory currently has only one laboratory on the first floor of the material 216.
　　 After being upgraded to level 2, its volume has increased to 1,000 cubic meters, which is 10 times larger, and there is still a lot of space to use.
　　 "System, can this XRD instrument be copied into the simulation laboratory?"
　　【Yes. The copy was successful. 】
　　 Xu Qiu discovered that a new room was opened in the simulation laboratory. It is the current room 104, and the XRD instrument is also in it.
　　 can be copied as expected, Xu Qiu thought:
　　 In this case, after copying all available instruments to the simulation laboratory, with the acceleration function, the experiment progress can take off.
　　 Now that the instrument has been copied, it is natural to copy the skills.
　　 Although the senior sister also has XRD skills, she must not be as proficient as Xu Hui.
　　 "The system records Xu Hui's X-ray diffractometer and atomic force microscope skills."
　　【Record successfully. 】
　　 Xu Qiu checked his proficiency, and it turned out that Mr. Xu Hui’s two skills were above 0% of the fifth level.
　　 After fixing these, Xu Qiu turned his attention back to reality.
　　The test result of the first sample has been released. The sample has three peaks at 7 degrees, 14 degrees, and 21 degrees.
　　 After testing the remaining three samples, it took just about half an hour.
　　 Copying data is a bit more complicated.
　　Usually, the computers of these large instruments and equipment are neither connected to the Internet nor directly plugged into the U disk to prevent viruses.
　　 It is necessary to share the folder to another computer through the network neighborhood to copy the data files.
　　 The two took the data, registered for the experiment, greeted Teacher Xu Hui, and left.
　　…………
　　 Back to the first floor of the material, Xu Qiu processed the XRD data that he had just received. After making the picture, he went to test the SEM with the school sister.
　　 came to the door of the SEM room, Xu Qiu saw that the door was covered with traces of time, and said:
　　 "This door looks so old, this electron microscope has been bought for many years."
　　 "It should be more than ten years," Chen Wanqing said: "So the images taken with it are sometimes blurry. It is estimated that this electron microscope will be retired in a few years."
　　 "But we just measure the thickness~EbookFREE.me~ and we don't have too high requirements. If you want to pursue the quality of the picture, you can go to the chemistry department to rub the equipment. They seem to have just replaced a new SEM instrument two years ago."
　　 After Xu Qiu knocked on the door, the two of them entered the room and suddenly came across with a chill.
　　 "Huh, it's cold." Xu Qiu shivered.
　　 "Yes, the operating temperature of SEM instruments is generally around 20 degrees, so in summer, the air conditioner needs to be turned on to the lowest level, and liquid nitrogen will be used later, and the temperature will be lowered." Chen Wanqing explained.
　　 Xu Qiu nodded and began to observe the SEM equipment.
　　 Although the door here is broken, the equipment is well maintained from the outside.
　　 A sample compartment is placed on an anti-vibration platform, and then an operating computer is connected, and an old teacher is sitting next to the computer.
　　 "Ms. Hu, let's take a cross-sectional SEM to measure the thickness of the sample," Chen Wanqing handed over the petri dish containing the sample.
　　 "This is a sample."
After 　　, Teacher Hu was operating the whole process, and Xu Qiu and Chen Wanqing sat and watched.
　　Because it is only to test the thickness of the sample, it is relatively simple. You only need to find the position of the film and glass, zoom in, place it in the center of the screen, and then take a picture.
　　 Teacher Hu will check with Chen Wanqing before taking a picture.
　　 Xu Qiu made five FAPbCl3 film samples at different concentrations, and finally got five pictures.
　　 From the computer window, you can see a bright perovskite film.
　　Through the software, Mr. Hu calculated the film thickness of each sample and marked it on the picture.
　　 Among them, the sample film thickness under optimal conditions is about 28 nanometers.
Before 　　 left, Xu Qiu also copied this laboratory and Mr. Hu's SEM skills.