A kind of differential scanning calorimeter of compatible visualization function
Technical field
The present invention relates to a kind of differential scanning calorimeter of compatible visualization function.
Background technology
Heat stream when differential scanning calorimeter (DSC) can be measured sample and varies with temperature phase transformation in the process.When sample generation crystallization, heat flow curve demonstrates corresponding exothermic peak, and when sample melted, heat flow curve then demonstrated corresponding absorption peak.Can extrapolate sample from the area at these peaks absorbs or liberated heat when changing mutually.However, differential scanning calorimeter can only reflect total heat that sample discharges or absorbs in quantity in the phase transition process, and can not provide the details of the structural change of sample own.
Microscope is a kind of material microstructure research Observations Means commonly used that is used for, such as macromolecular material, and aqueous solution, cell or biological tissue.By microscopic examination, can obtain the transient state information of sample micromechanism very intuitively, such as the poroid distribution of material, the crystallization behavior of solution, cell volume or shape or the like.
DSC and microscope can be used to investigate the response condition of material to temperature as the effective means of a pair of complementarity, more comprehensive result of study is provided.Yet, using this two kinds of methods independently, need test separately sample, because the difference of test environment often causes can not get very two kinds of data results of coupling, thereby limited comprehensive research to material temperature characteristic.
Summary of the invention
At the deficiencies in the prior art, the purpose of this invention is to provide in a kind of heat stream when measuring the sample phase transformation differential scanning calorimeter of compatible visualization function that can the structural change of test sample own.
For achieving the above object, technical scheme of the present invention is: a kind of differential scanning calorimeter of compatible visualization function, comprise the worktable that is provided with sample cell and reference cell, be located at and be used to carry sample in the sample cell and transmit the first hot-fluid detection part of heat flux with sample, be located at and be used to carry reference substance in the reference cell and transmit the second hot-fluid detection part of heat flux with reference substance, the temperature control equipment that respectively two hot-fluid detection parts is heated up and lower the temperature and control, the moisture recorder that is connected with two hot-fluid detection parts by thermocouple wire respectively, also comprise microscope image pick-up system and image capturing system, this microscope image pick-up system is by being located at sample viewing window on the sample cell sample micromechanism is observed and by image capturing system the sample microstructure change being carried out acquisition and recording.
This sample viewing window comprises the topped hole of being located at the sample cell top, be located at the hole, bottom of sample cell bottom and be located at through hole on the first hot-fluid detection part, topped hole, hole, bottom and through hole form a linear pattern transmitted light path, also be provided with a Polarizer or optical filter between sample and the topped hole, this microscope image pick-up system comprises the microscope image pick-up head of being located at the topped hole top and the microscope light source of being located at below, hole, bottom.
This hot-fluid detection part comprises the sample stage that is used to carry sample or reference substance, be located under the sample stage and the temperature sensor plate that is connected with thermocouple wire, be located at the hot-fluid road under the temperature sensor plate and whole parts are fixed in the fixed base plate of sample cell or reference cell, and this sample stage, temperature sensor plate, hot-fluid road and fixed base plate are formed with this through hole from top to down.
This sample stage is in the form of annular discs, and the hot-fluid road is a cylindrical-shaped structure, and this sample stage and hot-fluid road be axially symmetric structure, and this fixed base plate is rectangular shape.
This hot-fluid detection part adopts that stainless steel material is one-body molded to be made.
This sample is by being loaded into first sample cavity and being carried on the sample stage of the first hot-fluid detection part, this reference substance is by being loaded into second sample cavity and being carried on the sample stage of the second hot-fluid detection part, and this first, second sample cavity is that two transparent glass sheets and centre thereof sandwich the hollow cavity that the ring stainless steel film is made.
This temperature control equipment comprises that the liquid nitrogen refrigerating unit that two hot-fluid detection parts are lowered the temperature, the heat resistance type heating unit that two hot-fluid detection parts are heated up reach the temperature controller that is connected with the heat resistance type heating unit.
This heat resistance type heating unit is a heating element of being located at worktable bottom, and the liquid nitrogen refrigerating unit comprises Dewar flask, be loaded on the refrigeration source liquid nitrogen in the Dewar flask and an end is plugged in the Dewar flask and the other end is connected bottom worktable heat-conducting plate.
This image capturing system is connected to the data collection station machine, and this image capturing system viewed sample message of camera system that adjusts the telescope to one's eyes carries out collection analysis, carries out analyzing and processing by the data collection station machine again.
The present invention compared with prior art has following advantage and beneficial effect:
(1) strengthened the DSC function,, carried out visual observation when making DSC carry out heat flow measurement, overcome the deficiency that common DSC only is used as thermometric analysis sample by the view window of sample cell.
(2) element in the incorporate pond, assembling is simple, and temperature-responsive is good, has avoided causing when assembling because of different elements the thermal resistance that increases.
(3) operating temperature is low, need not compressor cooling, saves the energy.
(4) convenient directly perceived, simple to operate, the measurement stability height.
The present invention can realize a kind of heat flow flux type differential scanning calorimeter of compatible microexamination, and volume is little, and compact conformation is economical and practical.
Description of drawings
Fig. 1 is the structure cut-open view of the differential scanning calorimeter of the compatible visualization function of the present invention;
Fig. 2 is the fundamental diagram of the differential scanning calorimeter of the compatible visualization function of the present invention.
Embodiment
Below in conjunction with accompanying drawing the present invention is described in detail.
As shown in Figures 1 and 2, a kind of differential scanning calorimeter of compatible visualization function, comprise the DSC worktable 1 that is provided with sample cell 2 and reference cell 3, be located at and be used to carry sample in the sample cell 2 and transmit the first hot-fluid detection part 6a of heat flux with sample, be located at and be used to carry reference substance in the reference cell 3 and transmit the second hot-fluid detection part 6b of heat flux with reference substance, respectively to two hot-fluid detection part 6a, the temperature control equipment that 6b heats up and lowers the temperature and control, respectively by thermocouple wire 5a, 5b and two hot-fluid detection part 6a, the moisture recorder 18 that 6b connects, also comprise microscope image pick-up system and image capturing system 16, this microscope image pick-up system observes the sample micromechanism and surrounds and watches structural change by 16 pairs of samples of image capturing system and carry out acquisition and recording by the sample viewing window of being located on the sample cell 2.
This differential scanning calorimeter and microscope image pick-up system support are used, and sample is carried out hot-fluid test and micromechanism observation, finish real time image collection by data acquisition system (DAS).This worktable 1 is for copper product makes, and sample cell 2 is the hollow structure of worktable 1 inner two symmetries with reference cell 3.Sample cell 2 can be designed to difformity as required with the size and the size of reference cell 3, as cylindric or rectangular-shaped.
Thermocouple wire 5a, 5b include copper cash and constantan line, wherein the differential thermocouple that is connected to form a copper constantan-copper 4 of first copper cash, hot-fluid detection part 6a, constantan line, hot-fluid detection part 6b and second copper cash.Two copper wire access moisture recorder 18 with differential thermocouple collect the thermoelectromotive force that is equivalent to temperature difference between sample and the reference substance, convert heat flow signal output then to.Simultaneously, by 0 ℃ cold spot circuit (figure does not show), cut-in temperature registering instrument 18 after thermoelectromotive force-temperature transition, is exported the temperature of sample and reference substance respectively for thermocouple wire 5a, 5b.
This sample viewing window comprises the topped hole of being located at sample cell 2 tops, be located at the hole, bottom of sample cell bottom and be located at through hole on the first hot-fluid detection part, topped hole, hole, bottom and through hole form a linear pattern transmitted light path, also be provided with a Polarizer or optical filter 7 between sample and the topped hole, this microscope image pick-up system comprises the microscope image pick-up head 8 of being located at the topped hole top and the microscope light source 9 of being located at below, hole, bottom.
This hot- fluid detection part 6a, 6b comprise the sample stage that is used to carry sample or reference substance, be located under the sample stage and the temperature sensor plate that is connected with thermocouple wire 5a, 5b, be located at the hot-fluid road under the temperature sensor plate and whole parts are fixed in the fixed base plate of sample cell 2 or reference cell 3, and this sample stage, temperature sensor plate, hot-fluid road and fixed base plate are formed with this through hole from top to down.Wherein, thermocouple wire 5a, 5b can be fixed in the temperature sensor plate by welding manner, and fixed base plate is by on the bottom that is bolted to sample cell 2 or reference cell 3.
This sample stage is in the form of annular discs, and the hot-fluid road is a cylindrical-shaped structure, and this sample stage and hot-fluid road be axially symmetric structure, the Temperature Distribution when complete axisymmetric structure can alleviate hot-fluid and flows into sample stage.Fixed base plate adopts thin rectangular shape, is convenient to whole parts are fixed on sample cell or the reference cell.Hot-fluid flows to sample stage from the bottom of sample cell or reference cell through the hot-fluid road, thereby realizes the freezing of sample or reference substance or heating.
Hot- fluid detection part 6a, 6b adopt incorporate structural design, on the one hand for easy to assembly, and on the other hand also for fear of because of assembling the thermal contact resistance that different parts cause, thus the inflow of influence heat.The stainless steel material that the material selection of hot-fluid detection part is suitable lower than copper pyroconductivity.
This sample is by being loaded into the first sample cavity 14a and being carried on the sample stage of the first hot-fluid detection part 6a, this reference substance is by being loaded into the second sample cavity 14b and being carried on the sample stage of the second hot-fluid detection part 6b, and this first, second sample cavity 14a, 14b are that two transparent glass sheets and centre thereof sandwich the hollow cavity that the ring stainless steel film is made.This hollow cavity allows transmitted light to pass through, and is convenient to sample is observed.Sample cavity adopts clear glass to make, when light when send DSC worktable 1 bottom, can observe the inner structure of current specimen by microscope image pick-up head 8.
This temperature control equipment comprises that the liquid nitrogen refrigerating unit that two hot- fluid detection part 6a, 6b are lowered the temperature, the heat resistance type heating unit that two hot- fluid detection part 6a, 6b are heated up reach the temperature controller 19 that is connected with liquid heat resistance type heating unit.
This heat resistance type heating unit is a heating element 13 of being located at worktable 1 bottom, and the liquid nitrogen refrigerating unit comprises Dewar flask 11, be loaded on refrigeration source 12 in the Dewar flask 11 and an end is plugged in the Dewar flask 11 and the other end is connected with worktable 1 bottom heat-conducting plate 10.
This image capturing system 16 is connected to data collection station machine 17, and this image capturing system 16 viewed sample message of camera system that adjusts the telescope to one's eyes carries out collection analysis, carries out analyzing and processing by data collection station machine 17 again.
The principle of work of present embodiment is described below in conjunction with Fig. 1 and Fig. 2.Before sample is measured, at first sample is placed in the first sample cavity 14a and be put on the sample stage of the first hot-fluid detection part 6a, place reference substance in the second sample cavity 14b and be put on the sample stage of the second hot-fluid detection part 6b, begin to measure according to temperature program(me) then.Temperature controller 19 is freezing according to heating of instruction control heat resistance type heating unit or liquid nitrogen refrigerating unit.At this moment, hot-fluid is delivered on sample or the reference substance by fixed base plate, hot-fluid road at last from the bottom of worktable 1.In carrying out the process of temperature program(me), if sample undergoes phase transition and discharges or when absorbing heat, then the temperature of sample stage will change, and at this moment can read this variation on moisture recorder 18.Gather the inner structure of current specimen simultaneously by image capturing system, material temperature characteristic is done comprehensive research thereby greatly facilitate.
In addition, the refrigeration source liquid nitrogen can add inlet 20 free supplies by the liquid nitrogen of Dewar flask in test process.The addition of liquid nitrogen can be regulated according to the flexible in size of rate of temperature fall.When needs fast during rate of temperature fall, in Dewar flask 11, add more liquid nitrogen, by increasing the contact area between liquid nitrogen and the heat-conducting plate 10, realize fast rate of temperature fall.When the slower rate of temperature fall of needs, then reduce the addition of liquid nitrogen.When only needing to heat up, then do not need liquid nitrogen, only regulate heating element and carry out heating process by temperature controller 19.When carrying out the constant rate of speed cooling or heating up, 19 of temperature controllers according to the temperature signal that receives, are regulated heating power according to instruction automatically, to realize the freezing or heating to the sample constant speed.
When sample is tested, also need charging into nitrogen 15 in the sample cell as blanket gas.When probe temperature was lower than 0 ℃, nitrogen can also be used to stop the watch window frosting, and the light path when effectively protecting sample to observe is unobstructed.