火腿肠饵料对红火蚁引诱效果的对比研究

从火腿肠种类、诱饵放置距离、诱集时间3方面,对比研究12种火腿肠饵料对红火蚁的引诱效果。结果表明,猪肉以及脂类物质含量较高的蘑菇风味香肠、孜然风味香肠、特级火腿肠和盐水方腿香肠对红火蚁诱集效果最好,鸡肉火腿肠、玉米热狗肠、椰果烤香肠、原味烤香肠和香辣烤香肠对红火蚁工蚁的引诱效果次之,鱼肉肠、芝士鳕鱼肠和原味鳕鱼肠对红火蚁诱集效果相对较差。在试验设置距离范围内,距蚁巢20 cm和30 cm处各种火腿肠饵料的引诱效果最强,之后随着距离的增大引诱效果呈现下降趋势。蘑菇风味香肠、孜然风味香肠、特级火腿肠和盐水方腿香肠对红火蚁的持续诱集时间短于鱼肉肠、芝士鳕鱼肠和原味鳕鱼肠等,但最大召集红火蚁量高于后者,且能较快达到最大召集量。综上,猪肉以及脂类物质较多且肉香味浓郁的蘑菇风味香肠、孜然风味香肠、特级火腿肠和盐水方腿香肠对红火蚁引诱效果最好,诱集范围广,召集速度快,可优先选作红火蚁疫情调查与监测的诱饵。     

惠州市主要体育场馆红火蚁疫情及防控效果初报

调查了惠州市奥林匹克体育馆、金山湖体育馆等周边绿化区红火蚁疫情,并进行防控处理。调查表明,奥林匹克体育场与体育人才训练基地红火蚁疫情达到五级,属于严重危害区;金山湖游泳跳水馆红火蚁达到四级,属于中度危害区;金山湖体育馆红火蚁疫情为三级,属于轻度危害区。同时,采用诱饵法对防控效果进行了监测,随着施药时间的增长,防控效果愈高。药后7 d,红火蚁蚁丘减退率为77.9%~82.0%,工蚁诱集量减退率为60.0%~88.0%;药后15 d,蚁丘减退率上升至88.3%~91.0%,工蚁诱集量减退率高达88.6%~90.0%。药后40 d监测,防控效果均达100%,完全消除了红火蚁的蚁害威胁。     

不同饵料对红火蚁的引诱作用比较

测定不同饵料、不同香肠、不同时长对红火蚁的诱集作用。结果表明,不同饵料中火腿肠对红火蚁的诱集作用最强,红糖最低;不同香肠中以甜玉米香肠的引诱效果最佳,每瓶平均诱集工蚁为554.5头;诱集时长在30 min时工蚁诱集数达到最大,平均每瓶为508头。     

惠州仲恺高新区红火蚁疫情调查及防控

采用红火蚁克星─Ⅳ型诱杀饵剂对惠州市仲恺高新区及其周边绿化区的红火蚁进行了疫情调查和防控,处理结果表明:2个小区红火蚁疫情达到Ⅴ级,属于严重危害区;另有5个小区红火蚁达到Ⅳ级,属于中度危害区。施药后5 d,蚁丘周围开始出现死蚁,随着施药时间的延长,防控效果愈高。施药后7 d,红火蚁蚁丘的减退率为20.31%～33.33%,工蚁的诱集量减退率为46.28%～78.72%。15 d后,蚁丘减退率上升至49.41%～80.00%,工蚁诱集量减退率为79.55%～92.34%。药后30 d的工蚁平均减退率、蚁巢平均减退率分别为93.08%、88.64%。施药后6个月,工蚁平均减退率为99.01%,蚁巢平均减退率为98.04%,显著地消除了红火蚁的蚁害威胁。     

不同放置方式的诱饵对红火蚁的诱集作用比较

以诱饵诱集时间、工蚁诱集数、工蚁逃逸率3个指标评价了竹签 火腿肠片、标本瓶 火腿肠片2种诱饵诱集技术的监测效果.结果表明:竹签 火腿肠片的方式在25 min内工蚁诱集数达到最大,而标本瓶 火腿肠片的方式仅需要15 min,工蚁诱集数在达到最大值之后逐渐趋于稳定;2种诱集方式在30 min内工蚁诱集数差异不显著,工蚁逃逸率差异显著;从诱饵诱集率、工蚁诱集数2个方面综合考虑高、低密度诱饵数下的5种投放方式,得出"Z"字形是诱饵的最适合投放方式.     

广东红火蚁多个生境中诱饵对蚂蚁诱集作用比较

研究了荔枝园、荒草地和绿化带3种红火蚁Solenopsis invicta入侵生境中火腿肠、沙丁鱼、黄粉虫和蜂蜜4种诱饵及其组合对蚂蚁的引诱作用.结果表明,火腿肠、火腿肠 蜂蜜、沙丁鱼 蜂蜜这3种诱饵不仅能诱到较多的蚂蚁种类,也能诱到较多的蚂蚁数量;红火蚁对火腿肠的趋性最强,而火腿肠诱集其他蚂蚁的数量最少;通过对3种生境中不同诱饵诱集其他蚂蚁数量占所诱蚂蚁总数的百分比的分析发现,蜂蜜和加蜂蜜的诱饵诱集其他蚂蚁的数量最多;综合多方面的因素,在红火蚁发生区进行蚂蚁群落调查,火腿肠 蜂蜜和沙丁鱼 蜂蜜是最好的诱饵选择.     

冬季红火蚁蚁群结构特点

调查研究了冬季红火蚁Soenopsis invicta蚁群结构特点.结果表明,冬季红火蚁蚁群中职蚁占96.3%,职蚁中工蚁比例高达98.7%;幼蚁以幼虫为主,约占60%.1 cm2有效蚁丘表面基部面积和1 cm3蚁丘体积平均蚂蚁数量分别为287和24头.蚁群数量和不同品级数量随有效蚁丘表面基部面积、蚁丘体积间变化而变化,表现出较强规律.建立了蚁群总数、各品级数量和有效蚁丘表面基部面积、蚁丘体积间的14个模型.提出了推测单位面积上冬季蚁群数量的方法.     

一种新型监测诱饵对红火蚁的诱集效果分析

红火蚁(Solenopsis invicta Buren)是我国最具危险的外来入侵生物之一，对农林业生产、人畜健康、公共安全、生物多样性等均具有严重影响。根据国际上红火蚁防控经验来看，化学防治手段较为成熟，但关键问题还是如何早期发现红火蚁，而诱饵诱集是早发现红火蚁的一种高效方法。本文介绍了一种新型的红火蚁监测诱饵，并比较分析了该新型诱饵与市售火腿肠在诱集效果上的差异。结果表明，两种诱饵在5 min时已经诱集到红火蚁，两者之间的红火蚁数量差异不显著，而在15 min时，诱饵诱集到的红火蚁数量显著多于火腿肠；室外试验发现，新型诱饵与火腿肠的诱集效果无显著差异。鉴于新型诱饵的野外保鲜性、使用成本及操作便利等特点，我们认为新型诱饵更适用于红火蚁的监测调查。     

多杀菌素饵剂防治红火蚁田间药效试验初报

红火蚁是重要的危险性入侵害虫,目前国内尚没有相关防治药剂登记使用。为了明确0.015%多杀菌素毒饵颗粒剂对红火蚁的防治效果,试验评价了单蚁巢撒施毒饵的田间防效。试验结果表明,多杀菌素饵剂对红火蚁工蚁具有较强的诱食作用,药剂被带入蚁巢后,通过交哺作用,导致蚁后、幼蚁及其他工蚁死亡,药后25天蚁丘和蚁口减退率分别达到92.00%和92.39%,对红火蚁具有较好的田间防除效果,是一种安全、高效的红火蚁防治药剂。     

5种杀虫剂处理红火蚁工蚁活动性研究

采用刻度图示法评价5种杀虫剂处理红火蚁活动蚁巢对工蚁活动程度的影响,结果表明,红蚁净施药1d后工蚁活动性略减弱,但仍处于较高水平,且变化较小;绿爽处理后工蚁活动性显著下降,5～6 d后降至最低,之后呈上升趋势;红火蚁克星、灭蚁净、晔康3种药剂处理蚁巢后工蚁活动性随时间延长不断减弱,第9d下降至很低.建立了红火蚁工蚁活动性指数与杀虫剂处理后时间之间的多个多项式理论模型.考察了红火蚁克星使用剂量与红火蚁活动性关系,得出合适的使用剂量为15～25 g/蚁巢.     

Discovery of sodium in the atmosphere of mercury

The spectrum of Mercury at the Fraunhofer sodium D lines shows strong emission features that are attributed to resonant scattering of sunlight from sodium vapor in the atmosphere of the planet. The total column abundance of sodium was estimated to be 8.1 x 10(11) atoms per square centimeter, which corresponds to a surface density at the subsolar point of about 1.5 x 10(5) atoms per cubic centimeter. The most abundant atmospheric species found by the Mariner 10 mission to Mercury was helium, with a surface density of 4.5 x 10(3) atoms per cubic centimeter. It now appears that sodium vapor is a major constituent of Mercury's atmosphere.     

Oceanic electric fields: perception by american eels?

American eels, long-distance migrating fish, consistently exhibited conditioned cardiac deceleration responses to electric fields as small as 0.167 x 10(-2) microampere per square centimeter in water of resistivity 4000 ohm centimeters (6.7 microvolts per centimeter) and 400 ohm centimeters (0.67 microvolt per centimeter). Fewer responses were shown at this current density (0.167 x 10(-2) microampere per square centimeter) in more saline water (40 ohm centimeters, 0.067 microvolt per centimeter) and at a lower current density (0.167 x 10(-3) microampere per square centimeter) in fresh water. Thus, eels have sufficient sensitivity to utilize geoelectric information for orientation.     

Surface oxidation: a major sink for water on Mars

Surface oxidation irreversibly removes both oxygen and hydrogen from the martian atmosphere at a rate of 10(8) to 10(11) per square centimeter per second. This rate corresponds to a net loss of 10(25) to 10(28) per square centimeter (10(2) to 10(5) grams per square centimeter) of H(2)O, if it is assumed that the loss rate is uniform over geologic time. Heretofore, exospheric escape was considered to be the principal irreversible sink for H(2)O, but the loss rate was estimated to be only 10(8) per square centimeter per second. It is possible that surface oxidation may have had a minor effect on the supply of H(2)O in the regolith and polar caps.     

Density of the Lunar Atmosphere

The minimum possible density of the lunar atmosphere at the surface is shown to be essentially the value for the interplanetary medium. This value, when combined with the observed maximum, places the particle density between 10(3) and 10(6) per cubic centimeter, while the electron density must be about 10(3) to 10(4) per cubic centimeter. These results are markedly different from those recently obtained by Firsoff.     

A conducting polymer film stronger than aluminum

Polythiophene (Pth) was electrochemically deposited onto stainless steel substrate from freshly distilled boron fluoride-ethyl ether containing 10 millimoles of thiophene per liter. The free-standing Pth film obtained at an applied potential of 1.3 volts (versus Ag/AgCl) had a conductivity of 48.7 siemens per centimeter. Its tensile strength (1200 to 1300 kilograms per square centimeter) was greater than that of aluminium (1000 to 1100 kilograms per square centimeter). This Pth film behaves like a metal sheet and can be easily cut into various structures with a knife or a pair of scissors.     

Use of taylor-aris dispersion for measurement of a solute diffusion coefficient in thin capillaries

A method for the fast measurement of the diffusion coefficients of both small and large molecules in thin capillaries is reported. The method relies on Taylor-Aris dispersion theory and uses standard instrumentation for capillary zone electrophoresis. With this equipment, which consists of thin capillaries (50 to 100 micrometers in inner diameter), an injection system, detector ports, and computer data acquisition, a sample plug is pumped through the capillary at known velocity and the peak dispersion coefficient (D(*)) is measured. With the experimentally measured values of D(*) and flow velocity, and knowledge of the inner diameter of the capillary, the molecular diffusion coefficient (D) can be rapidly derived. For example, for ovalbumin a D value of 0.759 x 10(-6) square centimeter per second is found versus a tabulated value of 0.776 x 10(-6) square centimeter per second (error, 2 percent). For hemoglobin a D value of 0.676 x 10(-6) square centimeter per second is obtained versus a literature value of 0.690 x 10(-6) square centimeter per second (error, 1.5 percent).     

不同埋干深度对1年生楸树生长和生物量的影响

[目的]研究4种埋干深度对1年生豫楸1号生长和生物量的影响。[方法]埋干深度设计4种处理(10、20、30和40 cm),各处理分别选3株平均木,调查其一级侧枝的数量、长度和粗度,测量其胸径、树高及地上和地下生物量。[结果]4种埋干深度间,1年生楸树的侧枝数量、长度和粗度差异不显著,供试材料以埋干10 cm的平均枝条数和平均枝条粗度最大,埋干30 cm的平均枝条长度最大。各处理间胸径和树高总体随埋干深度的增大而变小,胸径差异呈显著性,树高差异不显著。地上生物量、茎生物量和枝生物量差异处理间达极显著,根生物量间差异显著,地上生物量和根生物量均随埋干深度的增加而减小。[结论]4种埋干深度对参试豫楸1号的胸径和生物量有不同程度的影响,埋干10 cm时,参试材料的胸径和生物量相对最大。     

Epitaxial cubic gadolinium oxide as a dielectric for gallium arsenide passivation

Epitaxial growth of single-crystal gadolinium oxide dielectric thin films on gallium arsenide is reported. The gadolinium oxide film has a cubic structure isomorphic to manganese oxide and is (110)-oriented in single domain on the (100) gallium arsenide surface. The gadolinium oxide film has a dielectric constant of approximately 10, with low leakage current densities of about 10(-9) to 10(-10) amperes per square centimeter at zero bias. Typical breakdown field is 4 megavolts per centimeter for an oxide film 185 angstroms thick and 10 megavolts per centimeter for an oxide 45 angstroms thick. Both accumulation and inversion layers were observed in the gadolinium oxide-gallium arsenide metal oxide semiconductor diodes, using capacitance-voltage measurements. The ability to grow thin single-crystal oxide films on gallium arsenide with a low interfacial density of states has great potential impact on the electronic industry of compound semiconductors.     

Venus: density of upper atmosphere from measurements of drag on pioneer orbiter

Measurements of the changes in orbital period of the Pioneer Venus orbiter have yielded estimates of the density of the upper atmosphere of Venus at altitudes in the range from 150 to 200 kilometers. At the lower limit of this range, the density on the dayside of the terminator exhibits a temporal variation of amplitude near 4 x 10(-14) gram per cubic centimeter aboult a mean of approximately 1.4 x 10(-13) gram per cubic centimeter. The variation appears oscillatory, with a 4- to 5-day period, but barely one cycle was observed. The density on the nightside of the terminator, sampled inthe same 150-kilometer altitude range, fluctuates about a smaller mean of approximately 4 x 10(-14) gram per cubic centimeter. The density between the altitudes of 150 and 200 kilometers, sampled only on the dayside of the terminator, imply a scale height of between 15 and 20 kilometers. The interpretation of this estimate is uncertain, however, in view of the measurements at the different altitudes having been made at different times and, hence, at different values of solar phase.     

Rapid formation of sulfuric acid particles at near-atmospheric conditions

We investigated the formation of new particles in a laboratory study, starting from H2SO4 produced in situ through the reaction of OH radicals with SO2. Newly formed particles were observed for H2SO4 concentrations above 7 x 10(6) per cubic centimeter. At 293 kelvin, a rough estimate yielded a nucleation rate of 0.3 to 0.4 particles per cubic centimeter per second for approximately 10(7) particles per cubic centimeter of H2SO4 (particle size >/= 3 nanometers). These findings are in agreement with observations from the atmosphere. The results demonstrate that under laboratory conditions similar to the atmosphere, particle formation occurs at atmospheric H2SO4 concentration levels.