ZnO/Cu/ZnO (ZCZ) thin films were deposited at room temperature on a glass substrate using direct current (DC) and radio frequency (RF, 13.56 MHz) magnetron sputtering and then the effect of post-deposition electron irradiation on the structural, optical, electrical and transparent heater properties of the films were considered. ZCZ films that were electron beam irradiated at 500 eV showed an increase in the grain sizes of their ZnO(102) and (201) planes to 15.17 nm and 11.51 nm, respectively, from grain sizes of 13.50 nm and 10.60 nm observed in the as deposited films. In addition, the film’s optical and electrical properties also depended on the electron irradiation energies. The highest opto-electrical performance was observed in films electron irradiated at 500 eV. In a heat radiation test, when a bias voltage of 18 V was applied to the film that had been electron irradiated at 500 eV, its steady state temperature was about 90.5 °C. In a repetition test, it reached the steady state temperature within 60 s at all bias voltages.

This study investigated durian (Durio zibethinus) peels to produce powdered activated carbon (DPAC). The influence of process variables such as carbonization temperature, activation time, contact time, CO2 flow rate, and adsorption dosage was optimized using response surface methodology (RSM). A six-factor and two levels Box–Behnken design (BBD) was used to optimize the parameters. The independent variables were activation temperature (°C), duration (min), CO2 flow rate during the activation process (L/min), irradiation of adsorbent (kGy), irradiation duration (min), and adsorbent dosage (g) while phenol removal (mg/L) was the dependent variable (response). Following the observed correlation coefficient values, the design was fitted to a quadratic model (R2 = 0.9896). The optimal removal efficiency (97.25%) was observed at an activation temperature of 900 °C, activation time of 30 min, CO2 flow rate of 0.05 L/min, irradiation dose of 100 kGy, contact time of 35 min and adsorption dosage of 0.75 g. The optimal DPAC showed a BET surface of 281.33 m2/ g. The removal efficiency was later compared with a commercially available activated carbon which shows a 98.56% phenol removal. The results show that the durian peel could be an effective precursor for making activated carbon for phenol removal, and irradiation can significantly enhance surface activation.

Individual multi-walled carbon nanotubes (MWCNTs) were exposed to the electron beam of 200 kV energy and high resolution transmission electron micrographs were recorded at several time intervals. Interestingly, the nucleation of diamond nanoparticles with in the highly disordered MWCNT matrix upon electron-irradiation is observed. This happens without any assistance of high pressures and temperatures. High pressure X-ray diffraction experiments were performed on core/shell structures which suggest that even the closed structures of carbon resist any inward pressure, thereby ruling out the possibility of a hypothetical internal pressure under the electron irradiation conditions. Our experiments suggest that the transformation of graphitic carbon into diamond in the size window of a few nanometers is possible due to the stability of the diamond and a selective dissolution effect of 200 kV electrons on graphite. A mechanism for the same is proposed.

Polyacrylonitrile (PAN)-based carbon fibers (CFs) and their composites, CF-reinforced plastics, have garnered significant interest as promising structural materials owing to their excellent properties and lightweight. Therefore, various processing technologies for fabricating these advanced materials using thermal energy have been intensively investigated and developed. In most cases, these thermal energy-based processes (heat treatment) are energy and time consuming due to the inefficient energy transfer from the source to materials. Meanwhile, advanced processing technologies that directly transfer energy to materials, such as radiation processing, have been developed and applied in several industrial sectors since the 1960s. Herein, general aspects of radiation processing and several key parameters for electron-beam (e-beam) processing are introduced, followed by a review of our previous studies pertaining to the preparation of low-cost CFs using specific and textile-grade PAN fibers and improvements in the mechanical and thermal properties of CF-reinforced thermoplastics afforded by e-beam irradiation. Radiation processing using e-beam irradiation is anticipated to be a promising method for fabricating advanced carbon materials and their composites.

감자뿔나방은 감자에 대한 검역 해충으로 알려져 있다. 본 연구는 전자빔 조사가 감자뿔나방의 발육 및 생식, 그리고 DNA 손상에 미치는 영향을 비교하고 억제선량을 조사하였다. 전자빔을 알(0-12시간 이내), 유충(3령과 5령), 번데기(용화 1일 이내), 그리고 성충(우화 1일 이내)에 선량을 증가시키면서 조사하였다. 전자빔 150 Gy는 알의 부화와 부화된 유충의 용화를 완전히 억제하였다. 조사된 알의 부화율은 19.3%였지만, 성충 우화는 완전히 억제되었다. 3령과 5령 유충에 100 Gy를 조사하였을 때, 성충의 우화와 생식은 완전히 억제되었다. 번데기와 성충에 각각 300 Gy와 400 Gy를 조사하였을 때, F1세대의 부화율이 억제되었다. 전자빔에 대한 감자뿔나방 성충의 DNA 손상 정도를 alkaline comet assay으로 분석하였으며, 전자빔 조사가 선량 의존적으로 감자뿔나방의 DNA 손상 정도를 증가시켰다. 이러한 결과는 감자뿔나방에 대한 식물 검역 처리법으로 전자빔 150 Gy를 권장할 수 있다. 하지만, 감자뿔나방을 방제하기 위해 전자빔을 현장에 적용하기 위해서는 추가적인 연구가 필요할 것으로 사료된다.

본 연구는 감마선 및 전자선 조사에 의한 닭고기 원료 사료 내에 존재하는 주요 위해 미생물을 비열처리 살균 효과를 검증하기 위하여 진행되었다. 일반세균, E. coli 및 Salmonella의 위해 미생물을 분쇄 닭고기 원료사료에 접종 후 3, 5, 7, 10 kGy의 전자선과 감마선으로 조사하였다. 전자선과 감마선 모두 3 kGy의 조사 시 시험된 미생물을 검출 한계 이하로 사멸시켜 분쇄 육류 원료 사료의 경우 3 kGy의 흡수선량이 충분한 비열 살균 조건임을 보여주었다. 방사선 조사에 의한 원료 사료의 품질 지표 변화를 알아보기 위하여 분쇄 닭고기의 조사 처리 후 pH 변화, 색도 측정, 전자코 이취 분석을 수행하였다. pH와 색도의 경우 감마선 및 전자선 조사에 의해 유의미하게 변화하지 않는 것으로 나타났다. 전자코 이취 시험의 경우 감마선 조사의 경우 3 kGy의 저선량 조사부터 이취가 발생되기 시작하였으며 10 kGy 조사 시 급격하게 이취의 정도가 증가하는 것으로 나타났다. 전자선 조사 역시 3 kGy의 조사부터 이취가 발생하였으며 5 kGy의 선량 이후 흡수선량이 증가함에 따라 이취가 점진적으로 증가하였다. 본 연구 결과 3 kGy의 저선량에서도 닭고기를 원료로한 펫푸드의 비열 살균 효과를 충분하게 이루어짐을 확인하였고 품질 지표에도 부정적인 영향을 주지 않는 것으로 나타났다. 이러한 비열처리 펫푸드의 살균 기술 개발은 국내 펫푸드 시장의 활성화와 반려 동물의 복지 향상에 기여할 것으로 기대된다.

A carbon fiber reinforced thermoplastic (CFRTP) was irradiated with a high energy electron-beam. As a result, the tensile strength of high-density polyethylene (HDPE)-based CFRTPs was significantly improved by gradually increasing the electron-beam dose. It was confirmed that the adhesion between CF and HDPE was improved and the surface properties of CF and HDPE were readily modified by electron-beam. It was verified from spectroscopic analysis that various oxygencontaining functional groups were formed on the surface of CF and HDPE by irradiation and we believe that strong attractive interactions took place among these functional groups at the interface of CFs and HDPE. Finally, it was conclusive that electron-beam irradiation provided two main effects on CFRTPs. One was cross-linking of thermoplastic resin for efficient load transfer from resin to CF and the other was formation of surface functional group and attractive interaction of these functional groups at the interface of fiber and matrix. These two effects showed synergetic contribution to enhance the mechanical properties of CFRTP.

호박꽃과실파리(Zeugodacus scutellata)는 국내 자생종으로 국제적으로는 검역 대상 과실파리 중 하나로 분류되고 있다. 불임충방사기술 (sterile insect release technique (SIT))은 검역 대상 과실파리를 박멸하는 데 이용되어 왔다. 본 연구는 호박꽃과실파리를 대상으로 불임충 제조 기술을 개발하여 SIT 기술로 이 해충에 대한 방제 가능성을 분석하였다. 이에 앞서 먼저 형광현미경 기술로 호박꽃과실파리의 생식관련 기관을 관찰하였다. 다영양실형 난소소관을 갖는 1 쌍의 난소는 약 100 개의 난포를 발달시키며, 각 난포는 난모세포와 영양세포를 지니며 난포세포가 둘러싸는 구조를 지닌다. 난소 발육은 우화 후 10 일이 지나 발육을 시작하고 우화 후 20 일이 되면 난각을 가지고 있는 난모세포를 발달시켰다. 수컷의 경우 성숙된 정소가 우화 직후에 관찰되었으며 수정관에는 운동성이 있는 정자로 채워져 있었다. 불임 수컷을 제조하기 위해 다양한 선량(0~1,000 Gy)의 전자빔을 3~5 일 경과된 번데기에 조사하였다. 200 Gy 세기 전자빔으로 번데기에 조사하면 무처리와 차이 없이 성충으로 발육하였고 이후 정상 암컷과 교미행동을 보였다. 비록 이들 처리 수컷의 교미는 무처리 수컷과 비교하여 큰 차이 없는 산란력을 보였지만 산란된 알들은 부화하지 못했다. 다음으로 200 Gy 조사로 형성된 불임 수컷을 정상 암컷과 수컷이 함께 있는 장소에 방사하였다. 이때 불임충 수컷은 정상 수컷에 비해 9 배 많은 수로 방사하였다. 이러한 불임충 처리는 차세대 부화율을 현격하게 감소시켰다. 이상의 결과는 200 Gy 세기의 전자빔 으로 호박꽃과실파리의 불임충을 제조할 수 있고, 이렇게 형성된 불임충은 SIT 방제에 적용할 수 있다는 것을 제시하고 있다.

Cymbidium flower is mainly grown for exportation to China and Japan, but detection of a few pests including the cotton aphid, Aphis gossypii (Hemiptera: Aphidae), necessitated post-harvest treatment for casual exportation. Thus, we irradiated electron beam to cotton aphids occurring in cymbidium to establish post-harvest method for casual exportation of the flowers. For cymbidium, six categories of product quality were examined after eight different doses were irradiated (100, 200, 300, 400, 500, 600, 800 and 1,000 Gy). One thousand Gy to cymbidium caused an extreme deterioration only in vase life in both colors compared to control (0 Gy). In the case of cotton aphids, adult longevity decreased from 11.23 (100 Gy) to 4.70 (400 Gy) when four different doses were irradiated (100, 200, 300, and 400 Gy), with control being an average of 20.89 days. The numbers of total first instar nymph produced per adult was not significantly differed among five doses (2.21 ~ 2.74 individuals), but was substantially lower compared to control (an average of 51.46; P < 0.0001). Live F1 nymphs did not develope to adults at all five doses, except for a single nymph at 100 Gy, which was dead right after emergence. The results of probit analysis indicated that majority of adults required 3.33 ~ 7.55 days for 90% mortality at 200 Gy and higher, but at 100 Gy it required 41.56 days. Therefore, higher than 100 Gy might be required for complete control of adult cotton aphids and their F1.

The effect of the ionization energy on the common house mosquito, Culex pipiens, pupa was investigated as the hatching rate, longevity and detoxification enzyme activity. The longevity of adult emerging in the pupa decreased depending on the exposure dose of Gray (Gy) in Cx. pipiens. The hatching rate of the F1 generation egg derived from Cx. pipiens pupa treated up to 70 Gy did not show any difference with the control, but the eggs did not hatch 100% at 120 Gy exposure. These results showed that Cx. pipiens was sterilized at 120 Gy. Several detoxifying enzyme (GST, non-specific esterase and MFO) activity of Cx. pipiens adult emerged from pupa irradiated with 120 Gy was investigated. The difference in activity was observed in female than in male irradiated with electron beam. As a result, electron beam irradiation seems to affect enzyme activity as well as induce infertility of Cx. pipiens.

The effects of electron beam(EB) irradiation on the electrical and optical properties of InGaZnO(IGZO) thin films fabricated using a sol-gel process were investigated. As the EB dose increased, the electrical characteristic of the IGZO TFTs changed from semiconductor to conductor, and the threshold voltage values shifted to the negative direction. X-ray photoelectron spectroscopy analysis of the O 1s core level showed that the relative area of oxygen vacancies increased from 14.68 to 19.08 % as the EB dose increased from 0 to 1.5 × 1016 electrons/cm2. In addition, spectroscopic ellipsometer analysis showed that the optical band gap varied from 3.39 to 3.46 eV with increasing EB dose. From the result of band alignment, it was confirmed that the Fermi level(EF) of the sample irradiated with 1.5 × 1016 electrons/cm2 was located at the closest position to the conduction band minimum(CBM) due to the increase of electron carrier concentration

The effect of electron beam (EB) irradiation on the electrical properties of Zn-Sn-O (ZTO) thin films fabricated using a sol-gel process was investigated. As the EB dose increased, the saturation mobility of ZTO thin film transistors (TFTs) was found to slightly decrease, and the subthreshold swing and on/off ratio degenerated. X-ray photoelectron spectroscopy analysis of the O 1s core level showed that the relative area of oxygen vacancies (VO) increased from 10.35 to 12.56 % as the EB dose increased from 0 to 7.5 × 1016 electrons/cm2. Also, spectroscopic ellipsometry analysis showed that the optical band gap varied from 3.53 to 3.96 eV with increasing EB dose. From the results of the electrical property and XPS analyses of the ZTO TFTs, it was found that the electrical characteristic of the ZTO thin films changed from semiconductor to conductor with increasing EB dose. It is thought that the electrical property change is due to the formation of defect sites like oxygen vacancies.

Monochamus saltuarius is one of the insect vector of pine wilt disease with Monochamus alternatus. The present study aimed to investigate the dose to induce sterile and the effect of sterility according to the gender of M. saltuarius. As the electron beam irradiation dose increased, the hatchability, adult eclosion rate and longevity of the former mid and late maturation feeding stage of adults was slightly reduced. However, there was no difference between these two adults. In addition, female adults were more sensitive to the electron beam than the male adults. Hatchability of the F1 generation of ♂T × ♀N o r♀T × ♂N (T: 200 Gy electron beam irradiation, N: 0 Gy) was completely suppressed. As electron beam irradiation dose increased, the fecundity of female adults were slightly decreased. Results by comet assay showed that electron beam irradiation induced as dose increased DNA damage in M. saltuarius adults. These results suggest that SIT using electron beam may be useful for control of M. saltuarius.

Monochamus alternatus is one of the insect vector of pine wilt disease with Monochamus saltuarius. The present study aimed to investigate the dose to induce sterile and the effect of sterility according to the gender of M. alternatus. As the electron beam irradiation dose increased, the longevity of the mid and late maturation feeding stage of adults was slightly reduced. However, there was no difference between these two adults. In addition, female adults were more sensitive to the electron beam than the male adults. Hatchability of the F1 generation of ♂T×♀N or ♀T×♂N (T: 200 Gy electron beam irradiation, N: 0 Gy) was completely suppressed. As electron beam irradiation dose increased, the fecundity of female adults were slightly decreased. Results by comet assay showed that electron beam irradiation induced as dose increased DNA damage in M. alternatus adults. These results suggest that SIT using electron beam may be useful for control of M. alternatus.

Ionizing irradiation can be used as an alternative to chemical fumigants for disinfestation of cut flowers, agricultural products, seeds, foods, medical products, and spices. In this study, we investigated the effect of electron beam irradiation on reproduction and development in Spodoptera litura. When irradiated to the adults, there was no difference in fecundity. However, egg hatching was considerably decreased. When irradiated to the pupae, fecundity was decreased as dose increased and wing deformity of newly emerged adults was increased as time passed. When irradiated to the larvae, developmental period and pupa deformity was significantly increased. In order to investigate the molecular mechanism of sterility and abnormal development, we performed quantitative real-time PCR and SDS-PAGE.

In order to study the impact of atmosphere during electron beam irradiation (EBI) of polyacrylonitrile (PAN) precursor fibers, the latter were stabilized by EBI in both air and oxygen atmospheres. Gel-fraction determination indicated that EBI-stabilization under an oxygen atmosphere leads to an enhanced cyclization in the PAN fibers. In the Fourier-transform infrared spectroscopy analysis, the PAN fibers stabilized by EBI under an oxygen atmosphere exhibited a greater decrease in the peak intensity at 2244 cm-1 (C≡N vibration) and a greater increase in the peak intensity at 1628 cm-1 (C=N absorption) than the corresponding PAN fibers stabilized under an air atmosphere. From the X-ray diffraction analysis it was found that oxygen uptake in PAN fibers leads to an increase in the amorphous region, produced by cyclization.

In this study, enhanced cation exchange capacity of polystyrene (PS) electrospun fibers by electron beam irradiation was investigated. PS spinning solutions were prepared by dissolving 25 wt% PS in 75 wt% mixed solvents (dimethylacetamide (DMAc)/tetrahydrofuran (THF)) at the ratio of 33/67% v/v with divinylbenzene (DVB; 0, 1, 2 phr)　as crosslink agent. The PS electrospun fibers were carried out at doses of 0 (control), 100 and 200 kGy. The ion exchange capacity (IEC) of PS electrospun fibers depend on the DVB concentration and irradiation dose. The PS electrospun fiber with DVB 1 phr at dose of 150 kGy showed the maximum IEC of 4.670 mmol/g.