本文選題：類丁二炔 + 吸收劑量��； 參考：《中國(guó)工程物理研究院》2015年碩士論文

【摘要】：劑量控制是核技術(shù)應(yīng)用中輻照質(zhì)量控制的一個(gè)關(guān)鍵因素,需要通過(guò)精確的方法進(jìn)行測(cè)量,以保證受輻照物質(zhì)的吸收劑量滿足要求。在輻射加工過(guò)程、核電機(jī)組內(nèi)、腫瘤的放射治療和一些特殊狹小異形環(huán)境的科學(xué)實(shí)驗(yàn)中需要進(jìn)行三維空間的劑量標(biāo)定,這就要求劑量計(jì)具有三維、高精度、靈敏和可塑的特性。目前常用的輻射劑量計(jì)主要包括量熱計(jì)、電離室劑量計(jì)、硫酸亞鐵(Fricke)劑量計(jì)、自由基劑量計(jì)和薄膜劑量計(jì)等。相比之下,凝膠劑量計(jì)具有體積小、制備簡(jiǎn)單、測(cè)試方便等優(yōu)點(diǎn),并且能夠在特殊的狹小異形環(huán)境中進(jìn)行三維空間的劑量測(cè)定。類丁二炔受到電離輻照后會(huì)發(fā)生輻射聚合反應(yīng),產(chǎn)生明顯的顏色變化。由于其吸光度響應(yīng)與吸收劑量相關(guān),因此可以利用類丁二炔受輻照前后的吸光度變化來(lái)表征吸收劑量。根據(jù)這一特性,可以將類丁二炔與凝膠載體相結(jié)合制備出含類丁二炔的凝膠復(fù)合材料,用于三維空間劑量分布的測(cè)定。本文中使用的類丁二炔為10,12-二十五碳二炔酸,通過(guò)旋轉(zhuǎn)蒸發(fā)儀蒸干成膜,加入去離子水后超聲,自組裝形成囊泡溶液。將其固載于選取的凝膠載體之中,制備成具有輻射變色響應(yīng)特性的凝膠復(fù)合材料。利用60Co-γγ輻射源對(duì)類丁二炔和凝膠復(fù)合材料進(jìn)行輻照實(shí)驗(yàn),詳細(xì)研究了類丁二炔輻射反應(yīng)機(jī)理和類丁二炔復(fù)合材料的劑量響應(yīng)、劑量率效應(yīng)、輻射后效應(yīng)和溫度效應(yīng)。為避免高劑量率γ輻照源的準(zhǔn)直性較差帶來(lái)的誤差影響,利用電子加速器考察了類丁二炔囊泡在凝膠體系中的擴(kuò)散效應(yīng)。最終本論文得出以下結(jié)論：1.瓊脂糖和丙烯酰胺兩種凝膠體系經(jīng)γ輻照后的力學(xué)性能和化學(xué)性質(zhì)均有所改變。瓊脂糖凝膠在輻照過(guò)程中出現(xiàn)一定程度的降解,力學(xué)性能隨吸收劑量的增加而降低,體系經(jīng)輻照后出現(xiàn)羰基,并生成少量的無(wú)害氣體。丙烯酰胺凝膠在輻照過(guò)程中發(fā)生二次交聯(lián),隨著吸收劑量的繼續(xù)增加,5 k Gy之后發(fā)生降解,其化學(xué)結(jié)構(gòu)穩(wěn)定,經(jīng)輻照后沒(méi)有新的官能團(tuán)產(chǎn)生,輻照后產(chǎn)生極少量的無(wú)害氣體。2.通過(guò)對(duì)類丁二炔囊泡的輻射變色機(jī)理研究發(fā)現(xiàn),類丁二炔囊泡體系經(jīng)γ射線輻照后,體系中水輻解產(chǎn)生的·H或·OH等自由基引發(fā)類丁二炔單體聚合,分子結(jié)構(gòu)由C≡C-C≡C的π-π共軛逐漸轉(zhuǎn)變?yōu)閇C≡C-C=C]n的大π鍵共軛結(jié)構(gòu)從而顯色。類丁二炔囊泡體系經(jīng)γ輻照后主吸收峰位于660 nm左右,吸光度隨吸收劑量增大而增大；拉曼光譜的特征吸收峰向低波數(shù)移動(dòng)同樣可歸因于隨吸收劑量的增大,共軛體系變大,導(dǎo)致分子振動(dòng)能級(jí)降低。3.以瓊脂糖凝膠為載體和丙烯酰胺凝膠為載體的類丁二炔凝膠復(fù)合材料分別在500～2000 Gy和50～2000 Gy的吸收劑量范圍內(nèi)具有良好的線性響應(yīng)；兩種復(fù)合材料總吸收劑量相同的情況下吸收劑量響應(yīng)與所研究的劑量率范圍(0.1～40 Gy/min)無(wú)關(guān)；樣品輻射后效應(yīng)不明顯,輻照后24 h體系吸光度基本不變；同時(shí)兩種凝膠復(fù)合材料的劑量響應(yīng)不受分次輻照的影響,隨溫度變化有一定程度波動(dòng)。4.經(jīng)準(zhǔn)直的電子束輻照,復(fù)合材料的變色范圍隨時(shí)間的推移無(wú)明顯變化。由于類丁二炔囊泡被固載于凝膠體系之中沒(méi)有出現(xiàn)擴(kuò)散現(xiàn)象,因此類丁二炔凝膠復(fù)合材料可以精確記載三維空間的劑量分布信息。5.本論文首次成功制備了以類丁二炔囊泡作為顯色劑的凝膠復(fù)合材料。在三維空間對(duì)γ射線具有良好的線性響應(yīng),為凝膠劑量計(jì)的進(jìn)一步發(fā)展提供了可參考的新方向。
[Abstract]:Dose control is a key factor in the radiation quality control of nuclear technology applications. It needs to be measured by a precise method to ensure that the absorbed dose of the irradiated material meets the requirements. In the radiation processing process, the three dimensional space needs to be carried out in the scientific experiments of the nuclear motor group, tumor radiation therapy and some special narrow and heteromorphic environments. Dose calibration, which requires the dosimeter to have three dimensional, high precision, sensitive and plastic characteristics. The current radiation dosimeters mainly include calorimeter, ionization chamber dosimeter, Fricke dosimeter, free radical dosimeter and thin film dosimeter. In contrast, the gel dosimeter is small in volume, simple in preparation and convenient in testing. It can be used to measure the dose of three-dimensional space in a special narrow and special-shaped environment. The radiation polymerization of the two alkyne can occur after ionizing radiation, which produces obvious color changes. As the absorbance response is related to the absorbed dose, the absorption of the butyrate two acetylene can be used to characterize the absorption of the absorbance before and after irradiation. According to this characteristic, the two alkynes of butyl two can be combined with gelatin carrier to prepare the gel composite containing two alkyne, which is used for the determination of the dose distribution in three-dimensional space. The dicyne two acetylene is used in this paper, which is twenty-five carbon and two alkynic acid, and is steamed by a rotary evaporator to form a film, adding deionized water after ultrasonic and self assembling to form a capsule. A gel composite was prepared in a selected gel carrier and prepared into a selected gel carrier. The 60Co- gamma ray radiation source was used to irradiate the two alkyne and gel composite materials. The radiation reaction mechanism of the butylene two acetylene and the dose response and dose rate effect of the butylene two alkyne composite were studied in detail. Post radiation effect and temperature effect. In order to avoid the error caused by the poor collimation of high dose rate gamma radiation source, the diffusion effect of two alkyne vesicles in the gel system was investigated by electron accelerator. Finally, the following conclusion was drawn: 1. the mechanical properties of two kinds of agarose and acrylamide gel systems after gamma irradiation. The chemical properties of the agarose gel were degraded to a certain extent. The mechanical properties of the gel decreased with the increase of the absorption dose. The carbonyl group appeared after irradiation and produced a small amount of harmless gas. The acrylamide gel occurred two times in the irradiation process, followed by the continued increase of the absorbed dose, after 5 K Gy. The chemical structure is stable, and the chemical structure is stable. After irradiation, no new functional group is produced. After irradiation, a very small amount of harmless gas.2. is produced through the study of the mechanism of radiation discoloration of the two alkyne vesicles. After gamma ray irradiation, the two alkyne vesicles in the system are irradiated by radiolysis. The free radical initiating two alkyne monomers, such as H or. The molecular structure is transformed from the pi - pi conjugation of C C-C C to the large pi bond structure of [C C-C=C]n. The absorption peak of the two alkyne vesicle system is about 660 nm, and the absorbance increases with the absorption dose, and the absorption peak of the Raman spectrum is also attributable to the absorption dose. With the increase of the conjugated system, the molecular vibration energy level is reduced by.3., and the two alkyne gel composites with agarose gel as the carrier and the acrylamide gel as carrier have good linear response in the range of 500~2000 Gy and 50~2000 Gy, respectively. The two composite materials have the same total absorption dose. The dose response has nothing to do with the dose rate range (0.1 ~ 40 Gy/min). The effect of the sample after radiation is not obvious. The absorbance of the 24 h system after irradiation is basically unchanged. At the same time, the dose response of the two gel composites is not affected by the fractional irradiation, and the.4. is irradiated by the collimated electron beam with a certain range of temperature variation. The color change range has no obvious change with time. As the two alkyne vesicles are immobilized in the gel system, there is no diffusion in the gel system. Therefore, the dosing two alkyne gel composites can accurately record the dose distribution information of the three-dimensional space.5. in this paper, the gel composite of the two alkyne vesicles is prepared for the first time in this paper. The material has good linear response to gamma rays in three dimensional space. It provides a new direction for further development of gel dosimeter.

【學(xué)位授予單位】：中國(guó)工程物理研究院
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TQ427.26;TB33

【共引文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 曹鴻斌;體部伽瑪?shù)兜膭┝繉W(xué)研究[D];清華大學(xué);2013年

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本文編號(hào)：1862779