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北缘地区温州蜜柑不同栽植方式和蜜度的效应研究
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作者 黄复瑞 《江西柑桔科技》 1990年第3期17-19,共3页
关键词 温州 栽培 蜜度 效应
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播期、密度和氮肥对小麦白粉病定量效应的研究 被引量:3
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作者 高智谋 檀根甲 +2 位作者 徐成勇 马夫柱 李自业 《安徽农业大学学报》 CAS CSCD 1993年第1期18-24,共7页
本文研究了播期、密度和氮肥对小麦白粉病及产量的定量效应,组建了病情指数及产量回归数学模型,并对其进行了检验和解析,结果表明:两回归模型均在0.01水平上显著,且拟合较好;三个因子对白粉病病指的影响为:播期>氮肥>密度,对产量... 本文研究了播期、密度和氮肥对小麦白粉病及产量的定量效应,组建了病情指数及产量回归数学模型,并对其进行了检验和解析,结果表明:两回归模型均在0.01水平上显著,且拟合较好;三个因子对白粉病病指的影响为:播期>氮肥>密度,对产量的影响为:播期>密度>氮肥;播期与氮肥互作对病指的影响达到0.05显著水平,播期与密度互作对病指及产量的影响分别在0.1和0.05水平上显著;早播稀植低氮措施组合有利于控制小麦白粉病,减少产量损失。最后对回归模型进行了仿真优化,提出了控病增产的栽培措施决策方案。 展开更多
关键词 小麦 白粉病 播期 蜜度 施肥 氮肥
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青蛤受精卵和幼虫密度对孵化和生长的影响 被引量:4
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作者 周琳 于业绍 +1 位作者 陆平 杨世俊 《海洋渔业》 CSCD 北大核心 1999年第4期157-159,共3页
本文报道了青蛤受精卵密度对孵化的影响和青蛤幼虫培养密度对生长的影响。受精卵密度在26个/ml、30个/ml、38个/ml、44个/ml、53个/ml时,孵化率在87.8~89.9%之间;受精卵密度为53个/ml时,幼虫畸形率较高。实验发现,幼虫的培养密度应控... 本文报道了青蛤受精卵密度对孵化的影响和青蛤幼虫培养密度对生长的影响。受精卵密度在26个/ml、30个/ml、38个/ml、44个/ml、53个/ml时,孵化率在87.8~89.9%之间;受精卵密度为53个/ml时,幼虫畸形率较高。实验发现,幼虫的培养密度应控制在6~11个/ml,幼虫变态后,减少培养密度,可以提高幼虫成活率。 展开更多
关键词 青蛤 蜜度 孵化 生长 受精卵 幼虫 育苗 贝类
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苹果黄始叶螨种群密度调查法研究
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作者 蔡如希 单虹丽 《西南农业大学学报(自然科学版)》 CSCD 1993年第4期339-342,共4页
运用零频率估计法估计苹果黄始叶螨种群密度与相应估计密度和实际密度值,吻合较好,二者差异不显著,平均误差小于0.2,精度 D 大于80%.Kuno 序贯抽样法在种群密度欠(2头/叶)、抽样数小时,可省时、省工作量.反之当种群密度小(1头/叶)时,则... 运用零频率估计法估计苹果黄始叶螨种群密度与相应估计密度和实际密度值,吻合较好,二者差异不显著,平均误差小于0.2,精度 D 大于80%.Kuno 序贯抽样法在种群密度欠(2头/叶)、抽样数小时,可省时、省工作量.反之当种群密度小(1头/叶)时,则抽样数大,与常规调查统计法相似. 展开更多
关键词 苹果红蜘蛛 种群蜜度 苹果
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关于提高杉木林分密度控制图整体精度的探讨 被引量:2
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作者 谢利玉 《中南林业调查规划》 1992年第1期43-48,共6页
林分密度控制图是利用数学模型研究密度与各测树因子之间的相互关系。文中通过二次回归法与Marquardt迭代法求解模型参数的比较,对五个等上层高线及三个等胸径模型进行了优化分析,结果表明:等上层高线以1/M=b_1H^(b_2)+b_3H^(b_4)/N与M=... 林分密度控制图是利用数学模型研究密度与各测树因子之间的相互关系。文中通过二次回归法与Marquardt迭代法求解模型参数的比较,对五个等上层高线及三个等胸径模型进行了优化分析,结果表明:等上层高线以1/M=b_1H^(b_2)+b_3H^(b_4)/N与M=b_1H^(b_2)N-b_3H^(b_4)N^2加权得到的组合模型为最优,等胸径线以与蓄积有关的模型M=b_1D^(b_2)N^(b_3)D^(b_4)为最佳。此外,通过对最大密度表的导算,编制了最大密度线并增加了一组等密度指数线。最后建议采用系数加权法提高蓄积估计精度。 展开更多
关键词 杉木 林分蜜度 控制图 整体精
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籽粒苋不同种植密度及不同种植时间产量对比试验
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作者 郑自轩 胡伯诚 张碧玉 《饲料研究》 CAS 北大核心 1991年第9期28-28,共1页
美国籽粒苋是美国菇代尔有机园艺场和农业研究中心从世界各地500多个籽粒苋品种中筛选出来的优质粮、饲、菜、观赏兼用的高蛋白植物,我县1986年从中国农科院引进,经过四年的试点、推广,每年3月上旬至8月上旬均可播种.为了提高籽粒苋的... 美国籽粒苋是美国菇代尔有机园艺场和农业研究中心从世界各地500多个籽粒苋品种中筛选出来的优质粮、饲、菜、观赏兼用的高蛋白植物,我县1986年从中国农科院引进,经过四年的试点、推广,每年3月上旬至8月上旬均可播种.为了提高籽粒苋的亩产量,取得更好的经济效益和社会效益。 展开更多
关键词 籽粒苋 种植蜜度 产量
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武术中长拳运动员训练强度和密度的研究——人体运动供能理论的运用
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作者 王玉珍 《湖北科技学院学报》 1992年第3期244-246,共3页
本文运用运动生理学的供能理论,对长拳运动员在训练过程中的肌肉活动的能量来源,应急能量、有氧能量进行分析,研究长拳运动员训练的强度和密度的特点.
关键词 供能 能源系统 蜜度
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蜂蜜掺假的特点及鉴别方法
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作者 张淑娟 《监督与选择》 1991年第3期26-27,共2页
关键词 质量检验 掺假类型 液粘稠
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Effect of Apis mellifera on community composition of local pollinator bees and their pollination network in Qinling Mountains and surrounding areas
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作者 Cheng'en ZHONG Qingle XIE +1 位作者 Yaoyao SI Yalin ZHANG 《Entomotaxonomia》 CSCD 2024年第3期167-205,共39页
The Qinling Mountains, known for their rich vegetation and diverse pollinating insects, have seen a significant decline in bee species richness and abundance over recent decades, largely due to the introduction and sp... The Qinling Mountains, known for their rich vegetation and diverse pollinating insects, have seen a significant decline in bee species richness and abundance over recent decades, largely due to the introduction and spread of Apis mellifera. This decline has caused cascading effects on the region's community structure and ecosystem stability. To improve the protection of native bees in the natural and agricultural landscape of the Qinling Mountains and its surrounding areas, we investigated 33 sampling sites within three habitats: forest, forest-agriculture ecotones, and farmland. Using a generalized linear mixing model, t-test, and other data analysis methods, we explored the impact of Apis mellifera on local pollinator bee richness, abundance, and the pollination network in different habitats in these regional areas. The results show that(1)Apis mellifera significantly negatively affects the abundance and richness of wild pollinator bees,while Apis cerana abundance is also affected by beekeeping conditions.(2)There are significant negative effects of Apis mellifera on the community structure of pollinator bees in the Qinling Mountains and its surrounding areas: the Shannon-Wiener diversity index, Pielou evenness index, and Margalef richness index of bee communities at sites with Apis mellifera influence were significantly lower than those at sites without Apis mellifera influence.(3)The underlying driver of this effect is the monopolization of flowering resources by Apis mellifera. This species tends to visit flowering plants with large nectar sources, which constitute a significant portion of the local plant community. By maintaining a dominant role in the bee-plant pollination network, Apis mellifera competitively displaces native pollinator bees, reducing their access to floral resources. This ultimately leads to a reduction in local bee-plant interactions, decreasing the complexity and stability of the pollination network. These findings highlight the need for targeted conservation efforts to protect native pollinator species and maintain the ecological balance in the Qinling Mountains. 展开更多
关键词 Apis mellifera Pollinator bees Species richness ABUNDANCE Interaction networks
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棉长管蚜和棉蚜对受蚜虫取食胁迫棉花植株的选择行为 被引量:3
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作者 闫文静 王俊刚 +1 位作者 张玉栋 吴娜 《新疆农业科学》 CAS CSCD 北大核心 2019年第1期52-60,共9页
【目的】研究棉长管蚜和棉蚜对其胁迫棉花的选择行为。【方法】以无翅棉长管蚜和棉蚜成蚜为研究对象,测定棉长管蚜和棉蚜对种群密度和不同时间蚜虫胁迫的棉花行为反应。【结果】不同种群密度棉长管蚜取食胁迫下,棉长管蚜对低密度取食胁... 【目的】研究棉长管蚜和棉蚜对其胁迫棉花的选择行为。【方法】以无翅棉长管蚜和棉蚜成蚜为研究对象,测定棉长管蚜和棉蚜对种群密度和不同时间蚜虫胁迫的棉花行为反应。【结果】不同种群密度棉长管蚜取食胁迫下,棉长管蚜对低密度取食胁迫的棉花与健康植株选择性上不存在差异性,而高密度则存在显著差异;棉蚜对高密度棉长管蚜取食胁迫选择性上存在显著差异。不同种群密度棉蚜取食胁迫下,棉长管蚜对被取食胁迫棉花与健康植株的选择性上不存在差异性,棉长管蚜能够适应棉蚜为害的棉花;而棉蚜对高密度棉长管蚜和棉蚜取食的棉花与健康植株选择性上存在显著差异,取食胁迫密度越高则选择差异性越大。随着棉长管蚜取食胁迫棉花时间的延长,棉长管蚜对短时间取食胁迫的棉花选择性上不存在差异性,而在取食胁迫3、5 d的棉花上存在显著差异;取食棉蚜仅在取食胁迫5 d的棉花上存在显著差异。棉蚜取食胁迫棉花不同时间后,不同受害程度棉花对后期棉长管蚜的寄主选择性不存在显著性差异。【结论】棉花蚜虫取食偏向选择健康植株,易造成田间扩散,导致棉花受害。棉长管蚜能够适应棉蚜为害的棉花,且与棉蚜长期在田间共存。 展开更多
关键词 棉长管蚜 棉蚜 棉花 取食胁迫 种群蜜度 行为反应
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Comparisons of Nectar Quantity and Sugar Concentration of Pomegranate Blossom in a Day 被引量:1
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作者 余玉生 卢焕仙 +2 位作者 宋文菲 张祖芸 张学文 《Agricultural Science & Technology》 CAS 2013年第1期69-71,共3页
[Objective] The aim was to research the rules of nectar quantity and sugar concentration of perfect and staminate flowers in a day. [Method] Based on nine Tianguang Yan pomegranate trees, nectar quantity and sugar con... [Objective] The aim was to research the rules of nectar quantity and sugar concentration of perfect and staminate flowers in a day. [Method] Based on nine Tianguang Yan pomegranate trees, nectar quantity and sugar concentration of per- fect and staminate flowers were measured and analyzed in morning and afternoon. [Result] Average nectar quantity and sugar concentration differed insignificantly in morning and afternoon of perfect flowers, which could also be applied to staminate flowers. However, average nectar quantity of perfect flower was 64.09 μI and of staminate flower was 44.07 μl. It is obvious that the two were of extremely signifi- cant differences (t=4.642, P〈0.01), and the former was significantly higher by 45,43%. On the other hand, average sugar concentration of perfect flower was 48.44% and of staminate flower was 37.16%. The two were of extremely significant differences and the former is higher by 30.36%, compared with the latter. These suggested that nectar quantity and sugar concentration would maintain unchanged in different periods for a day, if nectars are not consumed by pollinators, such as bees and butterflies. In the same period, nectar quantity and sugar concentration of per- fect flowers were higher than those of staminate flowers. [Conclusion] The research provides references for benefits increase of bee farmers and fruit farmers, as well as exploration of bee pollination. 展开更多
关键词 Quantity of secreted nectar Sugar concentration MEASUREMENT Com- parisons
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Synergistic Effects of Nitric Oxide and Harvest Maturity on Quality of Honey Peach during Cold Storage
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作者 胡花丽 李鹏霞 +1 位作者 王毓宁 李志强 《Agricultural Science & Technology》 CAS 2013年第4期549-553,共5页
In this study, peaches of cv. 'Sui Yuan' with different maturities were treated with 0.05 mM sodium nitroprusside (SNP), a nitric oxide donor, for 5 min, at 28℃, and then stored at 0-1.5℃ for 30 days. Untreated ... In this study, peaches of cv. 'Sui Yuan' with different maturities were treated with 0.05 mM sodium nitroprusside (SNP), a nitric oxide donor, for 5 min, at 28℃, and then stored at 0-1.5℃ for 30 days. Untreated fruits stored under the same conditions were used as control fruits in the experiment. The browning level, activities of polyphenol oxidase (PPO), peroxydase (POD) and superoxide dismutase (SOD), and quality parameters (firmness, titratable acid, total soluble solids and total sugar) were analyzed. The results showed that the firmness of SNP-treated fruit at different stage of maturity were higher than that of the control fruit after storage for 30 days. However, no significant effect was found on total soluble solid content. The titratable acid content of low maturity fruit was higher in SNP-treated one than that of the control, but the titratable acid content of high maturity fruit treated by SNP was lower than that of the control on 10th and 30th day. In addition, the combination of SNP treatment and high maturity resulted in higher activities of SOD, lower activity of PPO and POD, lower browning level. Therefore, the combination of high maturity and SNP treatment might be a useful method to well maintain honey peach fruit quality during cold storage. 展开更多
关键词 Honey peach Harvest maturity Sodium nitroprusside treatment QUALITY
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Analysis of Flavone Content in Honey of Pomegranate Flowers
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作者 卢焕仙 梁铖 +4 位作者 张学文 赵洪木 余玉生 宋文菲 王艳辉 《Agricultural Science & Technology》 CAS 2013年第1期166-168,共3页
[Objective] The aim was to analyze content of flavones in honey of pomegranate flowers. [Method] Contents of total flavones in 24 honey samples of pomegranate flowers from Mengzi City in 2011 and 2012 were measured as... [Objective] The aim was to analyze content of flavones in honey of pomegranate flowers. [Method] Contents of total flavones in 24 honey samples of pomegranate flowers from Mengzi City in 2011 and 2012 were measured as per- spectrophotometry method with acetone as an extractant and rutin as a control. [Result] The average content of flavones in honey of pomegranate flowers was at (2.36±1.36)mg/100 g in 2011 and significantly higher than that in 2012 at (1.71± 0.53)mg/100 g. Analysis was conducted on flavones content in different batches and the results indicated that content of flavones in honey in different batches changed from increasing to decreasing, namely, the content was maximal in peak flowering stage, followed by late flowering stage and initial flowering stage. [Conclusion] The research provides references for development, use and function exploration of the honey of pomegranate flowers. 展开更多
关键词 EXTRACT Honey in pomegranate flowers Total flavones Spectrophotome- try ANTHESIS
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核桃无性系早实丰产技术研究
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作者 余光英 胡国珍 李忠洪 《贵州林业科技》 1992年第3期1-7,共7页
利用当地核桃(Jaglans sigillata)复选优株和新疆早实核桃(J.ragia)的嫁接苗,进行栽植密度、施肥量、品种(含树种)三因子试验。结果表明,当地晚实核桃嫁接苗第2年便有少数植株开花挂果,第5年全部结果。早实核桃第2年全都结果。3年生部... 利用当地核桃(Jaglans sigillata)复选优株和新疆早实核桃(J.ragia)的嫁接苗,进行栽植密度、施肥量、品种(含树种)三因子试验。结果表明,当地晚实核桃嫁接苗第2年便有少数植株开花挂果,第5年全部结果。早实核桃第2年全都结果。3年生部分单株结果300多个、8年生产坚果892.5kg/ha。早期丰产密度以4m×4m为宜;幼树施肥氮,磷比以1:1配适量有机肥为好。采用良种核桃嫁接苗、合理密植和科学管理,都可使核桃早期丰产。 展开更多
关键词 核桃 早实丰产 无性繁殖 蜜度
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Kinetics of Reductive Leaching of Low-grade Pyrolusite with Molasses Alcohol Wastewater in H_2SO_4 被引量:17
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作者 粟海锋 刘怀坤 +2 位作者 王凡 吕小艳 文衍宣 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第5期730-735,共6页
The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the e... The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the effects of reaction parameters on leaching rate. The leaching rate increases with reaction temperature, concentrations of H 2 SO 4 and organic matter in molasses alcohol wastewater increase and ore particle size decreases. The leaching process follows the kinetics of a shrinking core model and the apparent activation energy is 57.5 kJ·mol –1 . The experimental results indicate a reaction order of 0.52 for H2SO4 concentration and 0.90 for chemical oxygen demand (COD) of molasses alcohol wastewater. It is concluded that the reductive leaching of pyrolusite with molasses alcohol wastewater is controlled by the diffusion through the ash/inert layer composed of the associated minerals. 展开更多
关键词 PYROLUSITE molasses alcohol wastewater reductive leaching KINETICS
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Optical Density and Antimicrobial Characteristics of Georgian Propolis
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作者 Ketevani Gabunia 《Journal of Pharmacy and Pharmacology》 2016年第3期146-150,共5页
Apiotherapy has been applied by Georgian people since time immemorial. Treatment with bee products in Georgia has been described in popular writings. Among bee products, honey and propolis are of most particular inter... Apiotherapy has been applied by Georgian people since time immemorial. Treatment with bee products in Georgia has been described in popular writings. Among bee products, honey and propolis are of most particular interest. Propolis is characterized by antimicrobial, antiviral, antioxidant, anticarcinogenic and analgesic properties. We have studied relationship between optical density and antimicrobial properties. Almost all samples of Georgian propolis are characterized by high optical density and antimicrobial activity. Studies have discovered that optical density was high in the samples of spring season. The maximal absorption values have been observed at a wavelength of 290-310 nm that is characteristic of flavonoids. Also, the sample with a relatively low optical density (Baghdati district) has exhibited antimicrobial activity that is conditioned not by polyphenols, but flavonoids. 展开更多
关键词 PROPOLIS FLAVONOIDS flavonones optical density antimicrobial activity.
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Sweet false stalk crusher
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作者 ZHANG Changcong WANG Qishen ZHANG Yan 《International English Education Research》 2016年第2期3-4,共2页
After finishing picking the banana, how to tackle banana pesudostem has long been a thorny problem. According to banana pesudostem's characteristics of more crassitude stem, high moisture content and heavy fiber dens... After finishing picking the banana, how to tackle banana pesudostem has long been a thorny problem. According to banana pesudostem's characteristics of more crassitude stem, high moisture content and heavy fiber density, this paper proposes a efficient, energy-saving and low-loss device for crushing banana pesudostems and returning field. 展开更多
关键词 STALK CRUSHING DEHYDRATION remming field
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The Effects of Temperature and Humidity around the Beehives on the Distribution of Nosema ceranae, and also Geographical and Seasonal Activity of the Infection in the Eastern Black Sea Region of Turkey.
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作者 Onur Tosun Mustafa Yaman 《Journal of Environmental Science and Engineering(B)》 2016年第11期513-522,共10页
20 localities were randomly selected in Eastern Black Sea Region of Turkey and samples were collected from around the beehives from April to September. Total of 4,640 dead adult worker bees were examined during the st... 20 localities were randomly selected in Eastern Black Sea Region of Turkey and samples were collected from around the beehives from April to September. Total of 4,640 dead adult worker bees were examined during the study. Total infection rate in worker bees was 21.23%. Nosema ceranae was identified in all localities with molecular techniques. Temperature and humidity values were measured from around the beehives during field studies. The infection rate ofN. ceranae increased proportionally with increasing temperature and humidity factors. Humidity was more effective than temperature on the infection rate ofN. ceranae. The seasonal activity ofN. ceranae was studied. The highest infection rates were observed in June and July. N. ceranae infection rate was higher in localities that were in low-altitude than in localities that were in high-altitude. 展开更多
关键词 Temperature humidity geographical distribution Nosema ceranae Apis mellifera Turkey.
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Highly Effective Detection of Amitraz in Honey by Using Surface-Enhanced Raman Scattering Spectroscopy Coupled with Chemometric Methods 被引量:1
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作者 Xin-ming Nie Jing Wang +4 位作者 Xun Wang Ya-ping Tian Si Chen Zhou-yang Long Cheng-hua Zong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第4期444-450,I0002,共8页
As an effective and universal acaricide, amitraz is widely used on beehives against varroasis caused by the mite Varroa jacobsoni. Its residues in honey pose a great danger to human health. In this study, a sensitive,... As an effective and universal acaricide, amitraz is widely used on beehives against varroasis caused by the mite Varroa jacobsoni. Its residues in honey pose a great danger to human health. In this study, a sensitive, rapid, and environmentally friendly surface-enhanced Raman spectroscopy method (SERS) was developed for the determination of trace amount of amitraz in honey with the use of silver nanorod (AgNR) array substrate. The AgNR array substrate fabricated by an oblique angle deposition technique exhibited an excellent SERS activity with an enhancement factor of -10^7. Density function theory was employed to assign the characteristic peak of amitraz. The detection of amitraz was further explored and amitraz in honey at concentrations as low as 0.08 mg/kg can be identified. Specifically, partial least square regression analysis was employed to correlate the SERS spectra in full-wavelength with Camitraz to afford a multiple-quantitative amitraz predicting model. Preliminary results show that the predicted concentrations of amitraz in honey samples are in good agreement with their real concentrations. Compared with the conventional univariate quantitative model based on single peak’s intensity, the proposed multiple-quantitative predicting model integrates all the characteristic peaks of amitraz, thus offering an improved detecting accuracy and anti-interference ability. 展开更多
关键词 AMITRAZ surface-enhanced Raman spectroscopy method Oblique angle deposition HONEY DETECTION SENSING Ag nanorod Density function theory Partial least squares regression
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绿壳蛋鸡育雏育成期饲养管理技术
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作者 熊国远 《养禽与禽病防治》 2000年第11期18-19,共2页
关键词 绿壳蛋鸡 育雏期 育成期 饲养管理 饲养蜜度
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