Phase separation dynamics analyzer is designed for laboratory immersion precipitation polymer membrane system during the design of sedimentation velocity measurements of optical instruments, the use of high-quality, high-precision optical design, high sensitivity of the measurement apparatus, showing the value of visual stability, operation simple, easy maintenance.。
Immersion precipitation phase inversion in the membrane process, the use of phase separation kinetics measured transmission through the membrane of the light intensity changes over time can be separated from the starting time and completion time, so different membrane system under the conditions of precipitation speed, is conducive to the process of film-forming kinetics. Experimental transmission of the principle is that when the casting film immersion coagulation bath, the casting solution as a result of liquid-liquid phase or liquid-solid phase precipitation occurs, then the transmitted light through the film strength of the casting solution with the precipitation weakened. Light intensity began to decrease the time for the beginning of phase separation time,。
Light intensity to a stable value of the view that the completion of phase separation.。
Specific light source to direct transmission of the polymer in the coagulation bath liquid, the detector perpendicular to the incident light axis in the direction of acceptance of the transmitted light through the membrane, and then by the signal amplifier, the signal into data, and finally by the computer data acquisition, data acquisition rate of 100 / s, and data into the worksheet at the same time given the intensity of transmitted light (transmittance) curve changes over time, that is, the formation of membrane permeability curve light. In the film formation process, the light transmission rate with the time gradually weakened.。
Measurement, including some of the major light source, sedimentation tanks, testing components. Specially designed light source is a specific light source, including the coagulation bath sedimentation tank, inlet, outlet and overflow pipes, testing components, including the probe, the signal amplifier.。
Characteristics:。
1, apparatus, using 90 ° transmitted light measurement;。
2, apparatus of the appearance of the use of streamline design, elegant appearance;。
3, apparatus is simple, intuitive graphics, high precision, good stability;。
4, apparatus is equipped with heating device coagulant, can be different when the coagulation bath temperature during the film formation speed of the changes in precipitation;。
5, coagulation bath using corrosion-resistant material, can solve the coagulation bath in this issue containing corrosive solvents;。
6, apparatus membrane by scraping with a glass plate by the optical cold working (grinding, polishing), to ensure the accuracy of the measurement apparatus;。
7, apparatus maintenance is simple, good reliability.。
Usage:
1, the installation of data processing software。
For this software installed on the WIN98 or XP or later system, run the installation program will automatically install to your computer system.。
After installation the database must be set up BDE, BDE buffer zone will be set to 4096K, see details in the installation directory "BDE buffer zone set up that" paper.。
2, parameter setting。
Running software click on the "set up and maintenance" to enter the settings menu.。
Serial port settings: Please set up the computer and devices connected to serial number;。
Error adjustment: general is set to 1;。
Test time: up to 15 minutes, set up after the completion of the "Save" button;。
3, test
Test Method 1:
Membrane test equipment ready by the "Acquisition" button, then click the main interface of the "immediate test" button, the system will be tested immediately, when the inlet valve should be open water, set time, the system will be automatically stop the test and save the data. Preservation of data and then a device must be the "Acquisition" button, cutting off communications, the end of the test. If you would like to drop the suspension of the test, click the main interface of the "Stop Test" button, the system will automatically stop the test and save the data. Preservation of data and then a device must be the "Acquisition" button, cutting off communications, the end of the test.。
Test Method 2:
Membrane in place to test the main interface, click the "Start Monitoring" button, when the main interface at the bottom right corner of the indicator light flashes red and green, press the device's "collect" button and open the water inlet valve, the system automatically tests. End with the stop method with the test method 1.。
4, data-processing records。
In the main interface, click on the "history view" can view the data recorded for each test.。
Naming test records:。
In the "total record test" to select records to be named, and then note the following file name box and then "√".。
To delete records:。
To delete a record selected in accordance with "-" keys.。
Export TXT file:。
To export records selected by the "Export TXT file", the system prompted to enter the file name, enter after the export has finished.。
手机信号 -90 dBm 为较差,刚好在移动规定的城市信号最低标准边缘(农村最低为-94 dBm),一般-60多到-70左右为强,如果信号极差,则常看到-100dBm以下的值,例如:-110dBm。
您好,local是建立局部坐标系的命令,坐标系号为12,L应该是你之前定义的一个参数,剩下的记不太清楚了,关于apdl命令流建议去查帮助文档,帮助文档解释的最清楚和明白,谢谢。。。
很高兴回答你的问题。
在C语言中使用ACSII表示字母的,A-Z的ASCII码是顺序的,也就是B比A大一,C比B大一。这样的话Z-A=25。所以需要表示的时候就是想要转换的字母减去A,再加一。比如输入了B:
char x=‘B’;
int i='B'-'A‘+1;
这样i的值就是2,输出就可以了。
希望对你有帮助。
上面说第二种是正确的请注意。
两种都不可以。你光声明的话可能编译器不会报错,
但是,你赋值试试就知道了
例如:
const int n = 10; 。
int a[n] = {0}; 。
不相信的可以自己试试。
测试环境Dev-C++(gcc) 。
有错误variable-sized object may not be initialized 。
意思是,变量大小的对象不能被初始化。
究其原因,请大家参考下面提供的const限定符的具体意义,
const只是限定该函数不可被修改。并不是真正意义上的常量。
宏定义不失为一种方法。不然就malloc、free或者new、delete。
解说完毕。
另:引用一篇文章里的:
关键字const有什么含意?
我只要一听到被面试者说:"const意味着常数",我就知道我正在和一个业余者打交道。去年Dan Saks已经在他的文章里完全概括了const 的所有用法,因此ESP(译者:Embedded Systems Programming)的每一位读者应该非常熟悉const能做什么和不能做什么. 如果你从没有读到那篇文章,只要能说出const意味着"只读"就可以了。尽管这个答案不是完全的答案,但我接受它作为一个正确的答案。(如果你想知道更详细的答案,仔细读一下Saks的文章吧。) 。
建议看一下http://linux.chinaitlab.com/c/713810_2.html。
**补充一下。我说的是C语言。不是C++。
C++的话第一种是错误的,第二种正确。