CN102247901B - Measuring flask used for preparation of volatile standard solution and application method thereof - Google Patents

Measuring flask used for preparation of volatile standard solution and application method thereof Download PDF

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CN102247901B
CN102247901B CN 201110093111 CN201110093111A CN102247901B CN 102247901 B CN102247901 B CN 102247901B CN 201110093111 CN201110093111 CN 201110093111 CN 201110093111 A CN201110093111 A CN 201110093111A CN 102247901 B CN102247901 B CN 102247901B
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volumetric flask
syringe
silica gel
bottle cap
gel sealing
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CN102247901A (en
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刘跟生
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State Grid Corp of China SGCC
Electric Power Research Institute of State Grid Shandong Electric Power Co Ltd
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State Grid Corp of China SGCC
Electric Power Research Institute of State Grid Shandong Electric Power Co Ltd
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Abstract

The invention relates to a measuring flask used for preparation of a volatile standard solution and an application method thereof. The measuring flask provided by the invention can prevent solute from volatilizing in a preparation process of the volatile standard solution, thus accuracy of the prepared standard solution is guaranteed, the problem that positive pressure and negative pressure exist in a volumetric flask in a solution preparation and suction process is solved, and the solution can be ensured to be easily injected and sucked in the standard solution preparation and suction process. The measuring flask comprises the volumetric flask, the neck of the volumetric flask is provided with an external thread which is matched with a screw thread of a cap; a silicone sealing gasket is arranged between the neck and the cap; and a central hole and a side hole are arranged on the cap.

Description

The measuring bottle and the using method thereof that are used for the preparation of volatility standard liquid
Technical field:
The present invention relates to the glass measurement instrument used a kind of assay laboratory, relate in particular to a kind of measuring bottle and using method thereof for the preparation of volatility standard liquid.
Background technology:
At present, the laboratory is when preparation volatility standard liquid, and employed solute and solvent in most cases have volatility.In process for preparation, volumetric flask adds solute and solvent under uncovered state, because solute and solvent have volatility, can cause the continuous volatilization of solute and solvent in operating process, thereby cause the concentration of standard solution of preparation inaccurate.
Chinese patent 200710021281 has provided a kind of for volatility titer preparation, special-purpose measuring bottle and the using method thereof of stocking, and it is made up of screw cap, silica gel sealing pad, T type silica gel sealing plug, volumetric flask.Its using method is:
After choosing the volumetric flask of respective volume, with the bottleneck of T type silica gel sealing plug plug at volumetric flask, in the ratio requirement according to predetermined compound concentration, each component is prepared in the liquid injection capacity bottle as transfer tool with syringe, method for implanting is: the micro-sampling pin of syringe is passed T type silica gel sealing plug, draw respectively with syringe in the preparation liquid and injection capacity bottle of various components, prepare and screw with threaded cap immediately after qualified, can store.When need using the volatility titer in the volumetric flask, the screw cap of outwarding winding, the silica gel sealing pad leaves bottleneck with screw cap, and T type silica gel sealing plug is still filled in the bottleneck at volumetric flask, the pin of syringe is passed T type silica gel sealing plug draw mark liquid in the volumetric flask.
Its shortcoming is mainly as follows:
The accuracy of standard liquid preparation is the basis that standard liquid stores, foregoing invention only seals at the capacity bottleneck with T type silica gel sealing padding when preparing standard solution, if the plug that assurance T type silica gel sealing pad can be firm need have enough silicon gel part to fill in the capacity bottleneck at the capacity bottleneck.When the standard liquid in the capacity is shaken up, need volumetric flask be inverted according to the strictness operation, attention then, repeatedly for several times, could be with the standard liquid mixing.And the permeability of part volatility organic solution is stronger, and the space between T type silica gel sealing pad and the volumetric flask wall may cause part organic solution to be infiltrated, thereby causes the concentration of standard solution prepared inaccurate.
During preparing standard solution, when syringe is extracted from T type silica gel sealing pad, since T type silica gel sealing pad and volumetric flask fix and all to realize by the tension force of T type silica gel sealing pad bottom, when extracting syringe, in order to guarantee that T type silica gel sealing pad is not pulled out, need pin T type silica gel sealing pad with hand, and then syringe is extracted, increase the inconvenience of operating process.If T type silica gel sealing pad might be extracted from the volumetric flask mouth because of carelessness in the operation, all that has been achieved is spoiled thereby cause seal operation.
Therefore when preparing standard solution, rely on T type silica gel sealing pad to seal merely and have certain defective.
In its using method " the micro-sampling pin of syringe is passed T type silica gel sealing plug, draw respectively with syringe in the preparation liquid and injection capacity bottle of various components, prepare screw with threaded cap immediately after qualified ".The using method statement is indeterminate, not the process of sake of clarity standard liquid preparation.In this process for preparation, except adding solute, also need to add the solvent constant volume.As if earlier solute being punctured in the T type silica gel sealing pad injection capacity bottle with micro syringe, puncture T type silica gel sealing pad with syringe then solvent is injected in the bottle, then because the excessive interior malleation of volumetric flask that causes of the volume of solvent is excessive, can't inject.If earlier certain solvent is injected in the bottle, build T type silica gel sealing pad then, puncture T type silica gel sealing pad with in the solute injection capacity bottle with syringe again, when the solute volume that injects is big, may can't inject because the excessive interior malleation of volumetric flask that causes of the solute volume that injects is excessive.
Draw in the method for standard liquid and " when needing to use the volatility titer in the volumetric flask; decontrol screw cap; the silica gel sealing pad leaves bottleneck with screw cap, and T type silica gel sealing plug is still filled in the bottleneck at volumetric flask, the pin of syringe to be passed T type silica gel sealing plug draw mark liquid in the volumetric flask." in the method, if when drawing the solution of large volume with syringe, then since in the volumetric flask negative pressure excessive, cause normally sucking-off of solution.
Summary of the invention:
In order effectively to address the above problem, the invention provides a kind of measuring bottle and using method thereof for the preparation of volatility standard liquid.Measuring bottle of the present invention can prevent the volatilization of solute in the volatility standard liquid process for preparation, thereby guarantee the accuracy of preparing standard solution, and solved the malleation and the negative pressure problem that exist in the volumetric flask in solution preparation and the suction process, guaranteed that solution can easily inject and draw in standard liquid preparation and the suction process.
For achieving the above object, the present invention adopts following technical scheme:
A kind of measuring bottle for the preparation of volatility standard liquid, it comprises volumetric flask, the volumetric flask bottleneck is provided with external screw thread, with the bottle cap threaded engagement; Be provided with the silica gel sealing pad between bottleneck and bottle cap; Be provided with medium pore and side opening at bottle cap.
Described volumetric flask is provided with graduation mark.
A kind of using method for volatility standard liquid preparation measuring bottle, when preparation volatility standard liquid, choose the volumetric flask of respective volume, do not cover at volumetric flask under the state of bottle cap, certain amount of solvent is moved in the volumetric flask, and the solvent volume that assurance has just added and solute volume sum to be added are near the volumetric flask graduation mark; The silica gel sealing pad is fixed in the interior top of chamber of bottle cap, and bottle cap is rotated with on the external screw thread of volumetric flask bottleneck by screw thread; Get a syringe needle, syringe needle is punctured the silica gel sealing pad by the side opening on the bottle cap, syringe needle enters in the volumetric flask; The syringe of measuring solute is punctured the silica gel sealing pad by the medium pore on the bottle cap, and syringe needle enters in the volumetric flask, and the assurance needle tip is annihilated by the liquid in the volumetric flask, slowly with in the liquid injection capacity bottle in the syringe; The needle and syringe head is extracted; The pin hole that the syringe of rinsing and draw solvent well is stayed along the silica gel sealing pad by the medium pore on the bottle cap penetrates in the volumetric flask, and the liquid of syringe needle this moment in can not the contact capacity bottle is slowly released the solvent in the syringe, is settled to scale; Syringe is extracted, and standard liquid shakes up.
When drawing the volatility standard liquid, get a syringe needle, the pin hole that syringe needle is stayed along the silica gel sealing pad by the side opening on the bottle cap penetrates in the volumetric flask; The pin hole that syringe is stayed along the silica gel sealing pad by the medium pore on the bottle cap penetrates in the volumetric flask, draws a certain amount of standard liquid; The needle and syringe head is extracted.
The present invention is used for the measuring bottle of volatility standard liquid preparation, formed by screw cap, silica gel sealing pad, volumetric flask with two holes, bottleneck at volumetric flask is established external screw thread, bottle at volumetric flask is provided with containing mark line accurately, be convenient to the volume of accurate constant volume solution, the silica gel sealing pad is arranged on the inner chamber end face of bottle cap, and bottle cap is rotated with on the external thread of bottleneck of volumetric flask by screw thread.The central authorities that a hole of bottle cap is positioned at bottle cap are as medium pore, the another one hole between medium pore and bottle cap edge as side opening.
Bottle cap and silica gel sealing pad with two holes is the key component of whole measuring bottle in the present invention, seals bottleneck by bottle cap and silica gel sealing pad, guarantees that the entire capacity bottle is in sealing state, avoids the volatilization of solute and solvent when preparation and absorption standard liquid.And the sealing of volumetric flask is realized that by the screw thread of threaded bottle cap and capacity bottleneck therefore, whole seal process is very fastening, the problem that the silica gel sealing pad comes off can not occur in the layoutprocedure of standard liquid.Directly contact the most effective contact area that has reduced silica gel sealing pad and volatile organic solvent with the volatility standard liquid by the silica gel sealing pad.In the process of preparing standard solution, the puncturing hole that forms by two hole puncture silica gel sealing pads on the bottle cap is more small, and the volatilization that can not cause the volatility standard liquid in the process is prepared and measured to the meeting auto-closing at the standard liquid of short time.
In the process for preparation of volatility standard liquid, when injecting the solute of larger volume, syringe is inserted medium pore, then syringe needle is inserted in the volumetric flask by side opening, the inside and outside pressure of guaranteed capacity bottle equates, thereby can be easy to inject quantitative solute.And in the injection process be annihilated by solvent in the tip of syringe needle, even there is a spot of volatilization also only to be the volatilization of solvent, thereby reduced the loss of solute to greatest extent.
Measuring in the process of volatility standard liquid, when measuring the standard liquid of larger volume, syringe is inserted medium pore, then syringe needle is inserted in the volumetric flask by side opening, the inside and outside pressure of guaranteed capacity bottle equates, thereby can be easy to draw quantitative standards solution.
Because the bottleneck of volumetric flask is fixed by bottle cap and silica gel sealing pad, in the process for preparation of volatility standard liquid, reduced to greatest extent join the devolatilization of solution.Because the contact volatile solvent soln of silica gel sealing pad minimum area, thereby guaranteed that to greatest extent the silica gel sealing pad contacts the loss that causes with volatile solvent soln.In the suction process of volatility standard liquid, be provided with the side opening on the screw cap, equate by inserting the pressure of syringe needle inside and outside can the guaranteed capacity bottle, inject or draw the interior malleation of volumetric flask or the bigger problem of negative pressure that larger volume solution may cause thereby solved, thereby but in volumetric flask, inject draw solution more easily.
Description of drawings:
Fig. 1 is the structural representation of measuring bottle of the present invention;
Fig. 2 is measuring bottle preparation volatility standard liquid of the present invention and the schematic diagram of drawing standard liquid.
Fig. 3 is medium pore and the side opening schematic diagram of measuring bottle screw cap of the present invention;
Among the figure: the 1-bottle cap; The 2-medium pore; The 3-side opening; 4-silica gel sealing pad; The 5-external screw thread; The 6-graduation mark; The 7-volumetric flask; The 8-syringe needle; The 9-syringe.
Specific implementation method:
The present invention will be further described below in conjunction with accompanying drawing and embodiment.
Among Fig. 1, Fig. 2, Fig. 3, the measuring bottle that is used for the preparation of volatility standard liquid, formed by bottle cap 1, silica gel sealing pad 4, volumetric flask 7 with two holes, establish external screw thread 5 at the bottleneck of volumetric flask 7, bottle at volumetric flask 7 is provided with containing mark line 6 accurately, silica gel sealing pad 4 is arranged on the interior top of chamber of bottle cap 1, and bottle cap 1 is rotated with on the external thread of bottleneck 5 of volumetric flask 6 by screw thread.
The using method of above-mentioned measuring bottle is as follows:
During preparation volatility standard liquid, choose the volumetric flask 7 of respective volume, do not cover at volumetric flask 7 under the state of bottle cap 1, certain amount of solvent is moved in the volumetric flask 7, the solvent volume that assurance has just added and solute volume sum to be added are near volumetric flask 7 graduation marks 6.Silica gel sealing pad 4 is fixed in the interior top of chamber of bottle cap 1, and bottle cap 1 is rotated with external thread of bottleneck 5 at volumetric flask 7 by screw thread.Get a syringe needle 8, syringe needle 8 is punctured the silica gel sealing pad by the side opening 3 on the screw cap, syringe needle enters in the measuring bottle.The syringe 9 of measuring solute is punctured silica gel sealing pad 4 by the medium pore 2 on the screw cap, and syringe needle enters in the volumetric flask 7, is annihilated by the liquid in the volumetric flask 7 in assurance syringe needle 8 tips, slowly with in the liquid injection capacity bottle 7 in the syringe 9.Syringe 9 and syringe needle 8 are extracted.The pin hole that the syringe 9 of rinsing and draw solvent well is stayed along silica gel sealing pad 4 by the medium pore 2 on the bottle cap 1 penetrates in the volumetric flask 7, this moment syringe needle 8 can not the contact capacity bottle liquid in 7, slowly the solvents in the syringe 9 are released, be settled to scale.Syringe 9 is extracted, and standard liquid shakes up.
When drawing the volatility standard liquid, get a syringe needle 8, syringe needle 8 is penetrated in the volumetric flask 7 by the pin hole that the side opening 3 on the bottle cap stays along silica gel sealing pad 4.Syringe 9 is penetrated in the volumetric flask 7 by the pin hole that the medium pore 2 on the bottle cap 1 stays along silica gel sealing pad 4, draw a certain amount of standard liquid.Syringe 9 and syringe needle 8 are extracted.

Claims (3)

1. a measuring bottle that is used for the preparation of volatility standard liquid is characterized in that it comprises volumetric flask, and the volumetric flask bottleneck is provided with external screw thread, with the bottle cap threaded engagement; Be provided with the silica gel sealing pad between bottleneck and bottle cap; Be provided with medium pore and side opening at bottle cap; Described volumetric flask is provided with graduation mark;
The silica gel sealing pad is arranged on the interior top of chamber of bottle cap.
2. the described using method for volatility standard liquid preparation measuring bottle of a claim 1, it is characterized in that, when preparation volatility standard liquid, choose the volumetric flask of respective volume, do not cover at volumetric flask under the state of bottle cap, certain amount of solvent is moved in the volumetric flask, and the solvent volume that assurance has just added and solute volume sum to be added are near the volumetric flask graduation mark; The silica gel sealing pad is fixed in the interior top of chamber of bottle cap, and bottle cap is rotated with on the external screw thread of volumetric flask bottleneck by screw thread; Get a syringe needle by side opening, will by the side opening on the bottle cap silica gel sealing pad be punctured by the syringe needle of side opening, the syringe needle by side opening enters in the volumetric flask; The syringe of measuring solute is punctured the silica gel sealing pad by the medium pore on the bottle cap, syringe needle by medium pore enters in the volumetric flask, assurance is annihilated by the liquid in the volumetric flask by the needle tip of medium pore, slowly with in the liquid injection capacity bottle in the syringe; With syringe and extracting by the syringe needle of medium pore; The pin hole that the syringe of rinsing and draw solvent well is stayed along the silica gel sealing pad by the medium pore on the bottle cap penetrates in the volumetric flask, this moment, the syringe needle by medium pore can not the interior liquid of contact capacity bottle, slowly the solvent in the syringe is released, be settled to scale; Syringe is extracted, and standard liquid shakes up.
3. the using method for volatility standard liquid preparation measuring bottle as claimed in claim 2, it is characterized in that, when drawing the volatility standard liquid, get a syringe needle by side opening, the pin hole that will stay along the silica gel sealing pad by the side opening on the bottle cap by the syringe needle of side opening penetrates in the volumetric flask; The pin hole that syringe is stayed along the silica gel sealing pad by the medium pore on the bottle cap penetrates in the volumetric flask, draws a certain amount of standard liquid; With syringe and extracting by the syringe needle of medium pore.
CN 201110093111 2011-04-14 2011-04-14 Measuring flask used for preparation of volatile standard solution and application method thereof Active CN102247901B (en)

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CN103170379A (en) * 2011-12-26 2013-06-26 合肥杰事杰新材料股份有限公司 Opening reactor
CN103728164B (en) * 2012-10-16 2016-03-30 辽宁奥克化学股份有限公司 The method of preparation epoxy compound standard solution and the method for mensuration epoxy compound substrate concentration
CN106769369B (en) * 2016-12-07 2019-06-04 中国计量科学研究院 Prepare container, the device and method of the organic mixed solution standard substance of volatility
CN113466011A (en) * 2021-07-26 2021-10-01 江苏省疾病预防控制中心(江苏省公共卫生研究院) Preparation method of microporous filter membrane quality control sample and quality control sample
CN114264535A (en) * 2021-11-29 2022-04-01 曼哈格检测技术股份有限公司 Method for preparing solution of volatile solute

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CN2548807Y (en) * 2002-05-29 2003-05-07 季忠伟 Rapid-blotting ink bottle
CN2745648Y (en) * 2004-11-10 2005-12-14 浙江大学 Standard solution reagent bottle
CN1631541A (en) * 2004-11-10 2005-06-29 浙江大学 Standard solution reagent bottle
CN100496750C (en) * 2007-04-15 2009-06-10 夏卫文 Special measuring flask for preparing and storing volatile standard liquid and using method thereof
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