The toxicity of materials derived from seed of Pongamia pinnata Pierre toward to third instar larvae of Aedes aegypti and Culex pipiens pallens was examined using direct contact bioassay. Results were compared with those of the currently used insecticides: fenthion and temephos. The active principles of Pongamia pinnata were identified as the karanjin (1), pongamone (2), palmitic acid (3) and karanjachromene (4), by spectroscopic analysis. Based on 24h LC50 values, karanjin (14.61 and 16.13 ppm) was the most toxic compound but less effective than fenthion (0.0031 and 0.068 ppm) and temephos (0.016 and 0.056 ppm) against Ae. aegypti and Cx p. pallens. Moderate toxicity was produced by pongamone (34.50 and 39.53 ppm), palmitic acid (36.93 and 42.96 ppm), and karanjachromene (43.05 and 48.95 ppm). P. pinnata seed derived materials, particularly karanjin, merit further study as potential mosquito larvicides for the control of mosquito populations in light of global efforts to reduce the level of highly toxic synthetic larvicides in the aquatic environment

The vapor phase repellency and toxicity of Zanthoxylum piperitum pericarp steam distillate (ZP-SD), Z. armatum seed oil (ZA-SO), and their 29 constituents to the adult female stable fly, Stomoxys calcitrans (Diptera: Muscidae), were examined using filter paper fumigation bioassay. Results were compared with those of the currently used repellent: DEET. Both of ZP-SD and ZA-SO exhibited vapor phase repellency and toxicity to female flies at 5 to 40 mg/filter paper (0.23 to 1.82 mg/cm3 air) during a 120-min exposure, whereas DEET exhibited neither repellency nor toxicity to the stable fly. At 5 mg/filter paper, vapor phase of ZP-SD and ZA-SO repelled 50 to 67% and 61 to 51% flies, respectively, to control area during 30 to 120 min. At 40 mg/filter paper, vapor phase of ZP-SD and ZA-SO caused 100% and 81% mortality, respectively, after 120 min of exposure. Among the tested volatile constituents, cuminaldehyde was the strongest repellent and toxic compound to the fly and was four times more toxic than ZP-SD and ZA-SO. Cuminaldehyde vapor phase repelled 62% flies to control area after 30 min at 2.5 mg/filter paper and caused 100% mortality after 120 min at 10 mg/filter paper. Based on the structure-activity relationships, the toxicity and repellency of constituents having aldehyde moiety were better than those of alcohol or ether one. Overall, ZP-SD, ZA-SO, and their bioactive constituents could be useful as potential vapor repellents to control stable fly population.

The toxicity of materials derived from rhizome of Cnidium officinale Makino to adults from B and Q biotype of Bemisia tabaci was examined using a leaf-dipping bioassay. Results were compared with those of two currently used insecticides: acetamiprid and thiamethoxam. The active principles of C. officinale rhizome were identified as butylidenephthalide (1), ligustilide (2), and 3-butylphthalide (3) by spectroscopic analysis. These compounds exhibited 100% mortality against both B and Q biotype adults at 2.5 mg/ml. At a concentration of 1.25 mg/ml, butylidenephthalide produced 88 and 92% mortality against B and Q biotype adults, respectively. 3-butylphthalide showed 100 and 89% mortality against B and Q type adults, respectively. Ligustilide exhibited 97 and 100% mortality against B and Q type adults, respectively. The toxicity of these compounds to B type adults was almost equal to that of thiamethoxam and acetamiprid, whereas two insecticides exhibited 40% mortality to Q biotype. C. officinale rhizome-derived materials merit further study as potential insecticides for the control of B. tabaci populations due to global efforts to reduce the level of highly toxic synthetic pesticides.

We investigated the effect of diameter and content of carbon nanotubes (CNTs) on the physical properties of styrenebutadiene rubber (SBR)/CNTs nanocomposites. CNTs-reinforced SBR nanocomposites were prepared by the melt mixing process. CNTs with different diameters were synthesized by the chemical vapor deposition method (CVD). In this work, the mechanical property and other physical properties of SBR/CNTS nanocomposites were discussed as a function of the content and diameter of CNTs.

전해제련 공정은 악티늄족 원소를 동시에 회수하는 공정으로써, Pyroprocessing의 핵확산 저항성을 보장 하는 중요한 공정이다. 공학규모의 전해제련 장치를 설계하기 위한 기본 도구를 개발하기 위해서 실험실 규 모의 장치에 대한 열전달 해석을 수행하였다. 열전달 해석을 수치 해석적으로 계산하기 위해 ANSYS CXF 상 용 코드를 사용하였다. 열전달 해석 결과, 가열부의 길이가 수직으로 용융염의 높이보다 약 3배 이상이 되었 을 때, 용융염의 온도를 일정하게 유지할 수 있었으며, 냉각부의 길이는 그 영향이 미비하였다. 전해조 덮개아래의 아르곤 가스의 온도는 냉각 판의 개수에 따라 감소하였으며, 5개 이상 설치 할 경우 250 ℃ 이하로 유 지할 수 있음을 보였다. 이러한 계산 결과는 실제 실험 장치에서 측정된 장치 내부 온도 분포와 경향성이 일 치하는 것을 볼 수 있었다. 본 연구에서 해석된 전해제련 장치의 열 분포 특성은 공학규모 장치의 설계를 위 해 중요한 자료로 사용 될 수 있을 것이다.

The fuel test loop consisted an in-pile test section (IPS) and an out-pile system (OPS) is an nuclear fuel irradiation test facility installed in HANARO and its operating temperature and pressure are similar to those of commercial nuclear power plant’s. Penetration pipe connecting the IPS and OPS at the reactor concrete wall is supported by pool-wall pipe support. The existing pool-wall pipe support established in the HANARO have insulations even thought the leak tightness is not ensured. So, the need for an isolation of the insulations from the HANARO cooling water makes the existing pool-wall pipe support newly designed. In this study a structural evaluation for the pool-wall pipe support in accordance with the 2001 ASME B&PV Section III NF is implemented. The most critical primary and secondary stress intensities occur at the modified connection area of the main cooling water pipe and plate ring, but those values are less than the allowable stress. It is concluded that the existing pool-wall pipe support could be modified to a newly designed shape having an isolated insulation from a HANARO cooling water.

The toxicity of Cyperus rotundus rhizome steam distillate constituents and their related compounds to adult females and males of the susceptible KS-BG strain and field-collected SR-BG and DR-BG colonies of Blattella germanica (L.) was examined using residual contact + fumigant and vapor-phase mortality bioassays. Results were compared with those of three organophosphorus (chlorpyrifos, dichlorvos, and fenitrothion), three carbamate (bendiocarb, dioxacarb, and propoxur), and three pyrethroid insecticides (bifenthrin, cypermethrin, and deltamethrin). In contact + fumigant mortality bioassay, p-cymene (LC50, 0.33 mg/cm2) was the most toxic terpenoid, followed by o-cymene, m-cymene, β-pinene, 1,8-cineole, and α-pinene, (LC50, 0.44–0.92 mg/cm2) against female B. germanica. These terpenoids were less toxic than the insecticides tested. Females were 3.1–3.6 times more tolerant than males to three cymene compounds. The toxicity of these monoterpenoids were almost identical against females from either of the three strains, even though the SR-BG and DR-BG females exhibited resistance to bifenthrin [resistance ratio (RR), 96 and 17], cypermethrin (RR, 67), deltamethrin (97 and 66), dioxacarb (19 and 22), and propoxur (24 and 32). In vapor-phase mortality bioassay, these monoterpenoids were effective in closed but not in open containers, indicating that the effect of these compounds was largely a result of vapor action. C. rotundus rhizome steam distillate and its constituents merit further study as potential insecticides for the control of insecticide-resistant B. germanica populations as fumigants with contact action.

The toxicity of 10 plant essential oils to adults of acaricide-susceptible, chlorfenapyr-resistant (CRT-53), fenpropathrin-resistant (FRT-53), pyridaben-resistant (PRT-53), and abamectin-resistant (ART-53) strains of Tetranychus urticae Koch and to female Neoseiulus californicus McGregor was examined using spray or vapor-phase mortality bioassays. In bioassay with the susceptible adults, strong toxicity was produced by lemon eucalyptus, peppermint, citronella Java, thyme red, caraway seed, pennyroyal, and clove leaf essential oils (LC50, 0.0193-0.0327 mg/cm3). The toxicity of these essential oils was almost identical against adults from either of the susceptible and resistant strains, even though CRT-53, FRT-53, PRT-53, and ART-53 adults exhibited high levels of resistance to chlorfenapyr [resistanc ratio (RR), >9140], fenpropathrin (RR, 94), pyridaben (RR, >390), and abamectin (RR,85), respectively. Against female N. californicus was 1.0 to 1.9 times more tolerant than T. urticae to the test essential oils. Thus, these essential oils merit further study as potential acaricides for the control of acaricide-resistant T. urticae populations as fumigants because of their lower toxicity to N. californicus.

The toxicity of materials derived from root of Asiasarum heterotropoides against early third instar larvae from susceptible Culex pipiens pallens, Aedes aegypti, and Ochlerotatus togoi was examined using direct contact mortality bioassays. Results were compared with those following the treatment with two currently used mosquito larvicides, temephos and fenthion. The bioactive principles of A. heterotropoides root were identified as asarinin, asarone, methyleugenol, pellitorine, and pentadecane by spectroscopic analysis. As judged by 24 h LC50 values, pellitorine (2.08-2.38 ppm) was the most toxic compound, followed by asarinin (10.49-16.49 ppm) and asarone (22.38-26.99 ppm). These compounds were less toxic than either temephos (0.16-0.20) or fenthion (LC50, 0.23-0.29). Weak activity was produced by methyleugenol (53.30-58.52 ppm) and pentadecane (96.71-99.19 ppm). A. heterotropoides root-derived materials, particularly pellitorine, merit further study as potential mosquito larvicides for protection from humans and domestic animals from vector-borne diseases and nuisance caused by mosquitoes.

The toxicity of melissa and savory essential oil constituents against adult Bemisia tabaci was examined using vapor-phase toxicity bioassay. Results were compared with those following the treatment with currently used insecticide dichlorvos. As judged by 24 h LC50 values, thymol (0.59×10-3 mg/cm3) was the most toxic constituent, followed by cavacrol (0.60×10-3 mg/cm3). These compounds were slightly less toxic than dichlorvos (LC50, 0.20×10-3 mg/cm3). Strong activity was also obtained from borneol (LC50, 1.06×10-3 mg/cm3), α-terpineol (1.22×10-3 mg/cm3), geraniol (1.23×10-3 mg/cm3), linalool (1.33×10-3 mg/cm3), lavendulol (1.44×10-3 mg/cm3), nerol (1.52×10-3 mg/cm3), β-citronellol (1.81×10-3 mg/cm3), terpinene-4-ol (1.87×10-3 mg/cm3), 1-octen-3-ol (2.06×10-3 mg/cm3), and citral (2.34×10-3 mg/cm3). The melissa and savory essential oil-derived compounds, particularly thymol and carvacrol, merit further study as potential insecticides for the control of B. tabaci.

The toxicity of materials derived from dried fruit of Cnidium monnieri against early third instar larvae of Culex pipiens pallens was examined using direct contact mortality bioassay. Results were compared with those of currently used mosquito larvicide, temephos. The bioactive principle was identified as xanthotoxol by spectroscopic analysis. As judged by 24 h LD50 value, xanthotoxol was highly effective (4.40 ppm), although this compound was less toxic than temephos (0.16 ppm). C. monnieri fruit-derived materials, particularly xanthotoxol, merit further study as potential mosquito larvicides for protection from humans and domestic animals from vector-borne diseases and nuisance caused by mosquitoes.

The toxicity of Kaempferia galanga rhizome materials and constituents against Meloidogyne incognita second‐stage juveniles (J2) and eggs were examined. The active principles of K. galanga rhizome were identified as the phenylpropanoids ethyl (E)‐cinnamate (EC, 1) and ethyl (E)‐p‐methoxycinnamate (EMC, 2) by spectroscopic analysis. Results were compared with those of carbofuran, fosthiazate, and metam‐sodium. In direct‐contact mortality bioassay, EC (LC50, 0.037 mg/ml) was the most toxic constituent, followed by EMC (0.041 mg/ml). EC was more effective than carbofuran (LC50, 0.092 mg/ml) but less active than fosthiazate (0.002 mg/ml). EC, egg hatch was inhibited 100, 93, and 87% at 125, 62.5, and 31.25 μg/ml, respectively. EMC caused 100, 81, and 75% inhibition of egg hatch at 125, 62.5, and 31.25 μg/ml, respectively. The inhibition of two phenylpropanoids were similar or more inhibition to that of either carbofuran or metam‐sodium but was lower than that of fosthiazate. In contact + fumigant mortality bioassay, EC and EMC treatments resulted in 86 and c 73% mortality at 0.5 and 0.125 mg/g soil, respectively. The lethality of these phenylpropanoids was almost similar to that of either carbofuran or metam‐sodium but was lower than that of fosthiazate. In vapor‐phase mortality bioassay, EC and EMC were more effective in closed container than open containers, indicating that the mode of delivery of these compounds was, in part, a result of vapor action. K. galanga rhizome‐derived materials, merit further study as potential nematicides and hatching inhibitors for the control of M. incognita populations.

One hundred seven plant essential oils were tested for insecticidal activities against Bemisia tabaci B and Q biotype adults, using the fumigation and direct spray methods. In the fumigation assay with the Q biotype adults, garlic oil was the most toxic (1.5×10-3 μl/cm3) on the basis of the LC50 value. Clove leaf, thyme, oregano (origanum), clove bud, savory, cinnamon bark, dabana, vetiver haiti and catnip essential oils also gave potent toxicity with the range of 1.7 to 4.5×10-3 μl/cm3 of LC50 values. These essential oils showed similar strong toxicity against B biotype. Based on the results obtained from fumigation test, nine plant essential oils were selected for the direct spray application at three concentrations (0.5, 0.1 and 0.02%). A litter difference was obtained between B and Q types in mortality to the tested oils. At the 0.5% concentration, they gave considerable mortality of 76 to 100%. At 0.1%, only garlic essential oil produced 96 to 100% mortality, but the others showed less than 76% mortality. Several plant essential oils appear to be candidates for the control of B. tabaci.

The larvicidal activity of materials from Ostericum koreanum (Apiaceae) root against late 3rd or early 4th instar larvae of Aedes aegypti and Culex pipiens pallens was examined using standard WHO technique under laboratory conditions. Results were compared with those of temephos. The biologically active constituents of O. koreanum root were characterized as four coumarines; isoimperatorin (I), osthol (II), oxypeucedanin (III) and imperatorin (IV) by spectroscopic analysis, including EI-MS, LC-MS, 1H NMR and 13C NMR spectroscopy. On the basis of 24-hr LC50 values, osthol among these four coumarines was the most toxic against Ae. aegypti (1.97 ppm) and Cx. pipiens pallens (1.87 ppm) larvae, but its activity was less than temephos (0.0047 and 0.013 ppm, respectively). LC50 values of isoimperatorin, oxypeucedanin and imperatorin derived from O. koreanum root against Ae. aegypti larvae were 2.46, 6.92 and 2.17 ppm, and against Cx. pipiens pallens larvae, were 1.99, 5.04 and 3.68 ppm. The results indicate that both materials and coumarines from O. koreanum root have potential to be used for mosquito control.

The acetylcholinesterase (AChE) inhibition of 12 plant-derived insecticidal compounds (anethol, anisaldehyde, 3-carene, 1,8-cineol, ethyl-cinnamate, linalool, magnolol, ethyl-p-methoxycinnamate, p-methoxycinamic acid, safrol, terpinen-4-ol, and α-terpineol) towards adult mosquitoes were examined by using Ellman method. Result were compared with those of dichlorvos, a potent AChE inhibitor. 3-Carene strongly inhibited AChE (IC50, 5.78×10-4 M), although the inhibition of the compound was lower than dichlorvos (IC50, 1.45×10-4 M). These results indicate that 3-carene acts as an AChE inhibitor, although an involvement of other insecticidal mechanism(s) might not be ruled out.

We recently described a novel animal model of trigeminal neuropathic pain following compression of the trigeminal ganglion (Ahn et al., 2009). In our present study, we adapted this model using male Sprague-Dawley rats weighing between 250-260 g and then analyzed the behavioral responses of these animals following modified chronic compression of the trigeminal ganglion. Under anesthesia, the rats were mounted onto a stereotaxic frame and a 4% agar solution (10μL) was injected in each case on the dorsal surface of the trigeminal ganglion to achieve compression without causing injury. In the control group, the rats received a sham operation without agar injection. Air-puff, acetone, and heat tests were performed at 3 days before and at 3, 7, 10, 14, 17, 21, 24, 30, 40, 55, and 70 days after surgery. Compression of the trigeminal ganglion produced nociceptive behavior in the trigeminal territory. Mechanical allodynia was established within 3 days and recovered to preoperative levels at approximately 60 days following compression. Mechanical hyperalgesia was also observed at 7 days after compression and persisted until the postoperative day 40. Cold hypersensitivity was established within 3 days after compression and lasted beyond postoperative day 55. In contrast, compression of the trigeminal ganglion did not produce any significant thermal hypersensitivity when compared with the sham operated group. These findings suggest that compression of the trigeminal ganglion without any injury produces prolonged nociceptive behavior and that our rat model is a useful system for further analysis of trigeminal neuralgia.

The toxicity of Kaempferia galanga rhizome-derived methanol extract (RME), powder (RP) and steam distillate (RSD) to Meloidogyne incognita second-stage juveniles (J2) and eggs and their effects on Lycopersicon esculentum germination and growth were examined in vitro and in pot experiments. Results were compared with those of three nematicides. In contact+fumigant bioassays with J2, RME applied at 1, 0.5 and 0.25mg/g soil exhibited 92, 88, and 73% mortality, respectively. The lethality of RME was almost similar to that of carbofuran but lower than that of either fosthiazate or metam-sodium. RSD and RP were less active than RME. In vapor-phase mortality bioassayswith J2, the test materials were effective in closed container than in open one, indicating that mode of delivery was, in part, a result of vapor action. RME, RSD, and fosthiazate treatments resulted in 91, 100, and 95% inhibition of egg hatch at 250μg/ml and 82, 88, and 81% inhibition of egg hatch at 100μg/ml, respectively. In filter-paper bioassays with L. esculentum seed at 8.8μg/cm2, RME and RP did not cause germination inhibition, while RSD and fosthiazate treatments resulted in 84 and 13% germination inhibition. In pot tests, RME and RSD applied at 8mg/g soil reduced galling caused by M. incognita significantly and fosthiazate at 0.02mg/g soil reduced galling completely. Rhizome materials did not cause any adverse effect on growth of L. esculentum, while fosthiazate application caused significantly reduced root weight. K. galanga rhizome-derived materials, particularly methanol extract, merit further study as potential nematicides and hatching inhibitors for the control of M. incognita populations as fumigants with contact action.

The toxicity of Asarum heterotropoides root steam distillate compounds to third instar larvae of Culex pipiens pallens, Aedes aegypti, and Ochlerotatus togoi (formerly Aedes togoi) was examined using a direct contact mortality bioassay. Results were compared with those following the treatment with fenthion and temephos. A. heterotropoides root steam distillate exhibited good larvicidal activity (21.07-27.64 ppm), based on LC50 values. Potent activity was produced by safrole (LC50, 8.22-16.10 ppm), terpinolene (11.85-15.32 ppm), -terpinene (12.64-17.11 ppm), (–)-β-pinene (12.87-18.03 ppm), (+)-limonene (13.26-24.47 ppm), 3-carene (13.83-19.19 ppm), and α-phellandrene (13.84-23.08 ppm), although the larvicidal activity of these compounds was less toxic than either fenthion (LC50, 0.023-0.029) or temephos (0.016-0.020). A. heterotropoides root steam distillate and its constituents described merit further study as potential mosquito larvicides for protection from humans and domestic animals from vector-borne diseases and nuisance caused by mosquitoes.