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Synthesis of new moth-proofing agents is necessary to overcome the damage caused by clothes moths and carpet beetles to hosiery and upholstery. In the present paper substituted benzyl 2-methyl-2-phenylpropyl ethers were synthesised and evaluated for moth-proofing activity. Two compounds were found to provide protection against larvae of Anthrenus fasciatus at levels of 1.0 and 10 g kg−1 respectively. The introduction of a methyl group in the para position of the benzene ring attached to C2 of the 2-methylpropyl chain (ring A) increased moth-proofing activity. The introduction of a phenoxy ring at the meta position of the benzyl nucleus (ring B) also increased activity, while the presence of a nitro group on the benzyl nucleus (ring B) decreased activity. © 1999 Society of Chemical Industry 相似文献
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光唇鱼与凡纳对虾池塘混养技术初探 总被引：1，自引：0，他引：1
在一口面积0．347hm2,水深2m的池塘放养体长2～4em的光唇鱼苗28000尾和体长0．8～1．0cm的凡纳对虾（俗称南美白对虾）虾苗100×10^4尾（分别在5月中旬和8月下旬2次投放,各投50×10^4尾）,经215d的饲养,收获商品光唇鱼295．3kg,折合产量851．0kg／hm2,成活率59％;两季对虾产... 相似文献
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暗纹东方鲀饲料中豆粕替代鱼粉的营养生理效应及其与大豆抗原蛋白的相关性 总被引：3，自引：1，他引：2
选择体质量为(39.84±3.09)g暗纹东方鲀,分为8组,分别饲喂等氮等能的高鱼粉组、低鱼粉组、低鱼粉发酵豆粕组、低鱼粉豆粕组4组实用饲料和添加大豆抗原蛋白的半纯化饲料(大豆抗原蛋白含量分别为0%、5%、8%和12.5%),进行为期两个月的生长实验,探讨大豆抗原蛋白对暗纹东方鲀生长和生理生化的影响。结果显示,用发酵豆粕替代部分鱼粉的低鱼粉发酵豆粕组生长性能显著优于低鱼粉组,用豆粕替代部分鱼粉的低鱼粉豆粕组与低鱼粉组无显著差异。半纯化饲料中随着大豆抗原蛋白含量增加,生长率呈现先增后降趋势;实用饲料和半纯化饲料对肌肉组成有不同程度的影响;在肝脏丙二醛、总抗氧化能力和血清丙二醛指标中,低鱼粉豆粕组显著高于低鱼粉组,低鱼粉发酵豆粕组则与低鱼粉组无显著性差异,半纯化饲料系列在8%组出现峰值,显著高于其他组。低鱼粉豆粕组血清谷草转氨酶活性显著高于低鱼粉组,低鱼粉发酵豆粕组与低鱼粉组相比无显著性差异,半纯化饲料组谷草转氨酶和谷丙转氨酶呈现先增后减趋势。研究表明,与豆粕替代鱼粉相比,用发酵豆粕替代鱼粉更能促进鱼体生长;大豆抗原蛋白是影响豆粕替代鱼粉效果的重要因素,但对生长、抗氧化性能和生理生化指标的影响则因大豆抗原蛋白的含量与单独存在与否而异。 相似文献
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东海条石鲷仔鱼耳石日轮与生长的关系 总被引：2，自引：1，他引：1
2009年4月15日-5月5日在浙江省舟山水产研究所条石鲷(Oplegnathus fasciatus)人工繁殖期间,逐日选择胚胎和仔鱼样本,连续解剖观察发育后期胚胎和前期仔鱼,光镜观察仔鱼矢耳石和微耳石的形态、日轮数,测定其直径,研究条石鲷的耳石日轮和生长。结果表明,受精后约26h,条石鲷胚胎听囊内出现1对矢耳石和1对微耳石;仔鱼孵出第2天形成第1个轮纹,之后每天形成1轮,孵化后天数(N)和矢耳石日轮数(D)的关系为N=D+1;在第8天左右,矢耳石上出现第2条明显的标记轮,为初次摄食轮。仔鱼耳石长径(rs,μm)与鱼体体长(L,mm)呈线性相关,其关系式为rs=18.146L-44.436;矢耳石长径rs与微耳石长径rl之间存在线性相关,其关系式为rs=0.6125rl+1.9882。根据结果确认,矢耳石轮纹可作为条石鲷仔鱼日龄的判别依据。 相似文献
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条石鲷仔鱼饥饿试验及不可逆点的确定 总被引：3，自引：0，他引：3
在盐度29、水温22~24℃的条件下,进行了条石鲷仔鱼饥饿试验和不可逆点(PNR)的确定;观察了饥饿条件下条石鲷初孵仔鱼、3、6、9、12、15日龄的存活、生长、卵黄囊与油球利用和游泳行为的变化。结果表明:饥饿会延缓初孵仔鱼对油球的利用。随着饥饿时间的延长,仔鱼的生长与正常条件下仔鱼差异显著(P<0.05)。条石鲷仔鱼从初次摄食到PNR期为2.5~3 d,这个耐受饥饿的时间临界点在孵化后的5~5.5 d。在饥饿的条件下初孵仔鱼、3、6、9、12、15日龄仔鱼的全部死亡时间分别为6.5、6、5、4、65、d;后5个日龄仔鱼半数死亡时间分别为4、3.5、3.5、3.5、3.5 d。说明9日龄是条石鲷早期发育中最为敏感的阶段。饥饿仔鱼体长较短,头大且体瘦,长期饥饿后脑后部下陷。饥饿仔鱼表层集群游动觅食,缓慢游动反应迟钝,静伏底。 相似文献
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A two‐factor experiment incorporating two photoperiods (16 L:8 D and 24 L:0 D) and four feeding intervals (6, 9, 12 and 24 h) was carried out to determine the most efficient feeding interval and photoperiod for striped knifejaw, Oplegnathus fasciatus. Fish were fed a commercial diet to apparent satiation for 10 weeks. Blood was collected to measure the stress indicators. Both the photoperiod and the feeding intervals had a significant effect on the growth performance of striped knifejaw; however, their interaction did not produce any significant effect. The final body weight, weight gain (%) and feed intake at 6‐, 9‐ and 12‐h feeding intervals under 16 L:8 D were significantly higher than those at the 24‐h interval irrespective of the photoperiod (P<0.05). The specific growth rate at 6, 9 and 12 h intervals of the 16 L:8 D photoperiod was significantly higher than that of the other feeding intervals, except at 12 h of the 24 L:0 D photoperiod (P<0.05). At the end of the experiment, there were no significant differences in the plasma levels of cortisol, glucose and total protein observed in fish exposed to different photoperiods compared with the initial levels. The results suggested that a combination of a 16 L:8 D photoperiod and either of 6‐, 9‐ or 12‐h intervals can be used to stimulate the growth performance in striped knifejaw. 相似文献
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Caio P Fernandes Alexandre Xavier João Pedro Furtado Pacheco Marcelo Guerra Santos Rodrigo Mexas Norman A Ratcliffe Marcelo Salabert Gonzalez Cícero Brasileiro Mello Leandro Rocha Denise Feder 《Pest management science》2013,69(2):292-301
BACKGROUND: Studies were carried out to evaluate the effects of Manilkara subsericea extracts and triterpenes on the development of two species of agricultural pest insects, Oncopelus fasciatus and Dysdercus peruvianus. RESULTS: All treatments of insects with M. subsericea extracts induced mortality, delayed development and inhibited moulting. Some extracts assayed (FH, FB and FD in D. peruvianus, and FH, FB and FEA in O. fasciatus) also produced body deformities in the few adults that emerged. Other extracts (FH, FEA, FB, FD and LET in both insects), however, induced either permanent (overaged) or extranumerary nymphs, both of which were unable to achieve the adult stage and reproductive status. The insects were also treated with triterpenes (α‐ and β‐amyrin acetates) which showed high lethality at 30 days after treatment and delayed the intermoult period so that overaged nymphs were detected. CONCLUSION: The results indicate that extracts and triterpenes from Manilkara subsericea act as potent growth inhibitors of phytophagous hemipteran nymphs. It is also concluded that the mixture of several different molecules in the extracts used produces synergic effects that do not occur after using the triterpenes (PFT) alone. These secondary metabolites in the M. subsericea extracts can potentially be used in integrated control programmes against crop pests. Copyright © 2012 Society of Chemical Industry 相似文献
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条石鲷早期发育阶段消化系统组织学研究 总被引：1，自引：0，他引：1
【目的】研究条石鲷Oplegnathus fasciantus从初孵仔鱼到幼鱼这一发育阶段消化系统的形态学变化和组织结构特征.【方法】利用形态学和连续组织切片技术,对出膜后0~35日龄的条石鲷各期仔、稚、幼鱼的消化系统进行了观察和研究.【结果和结论】在水温24~27℃,盐度29~30,p H 7.4~8.2的条件下,初孵仔鱼(0日龄仔鱼)消化道仅是一条位于卵黄囊后的尚未分化的细管状结构,卵黄囊体积较大,H-E染色呈淡红色.随着条石鲷的生长发育,其消化系统也在逐渐成熟和完善,条石鲷消化系统的发育完善要经过3个阶段,第1阶段是0~3日龄,消化道几乎未分化;第2个阶段为4~18日龄,消化系统初步发育成型,具备了基本的摄食、消化和吸收功能;第3阶段为19~35日龄,形成胃腺和幽门盲囊,消化系统发育完善,具备成鱼的结构. 相似文献
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