稀土微肥在平菇生产中的应用研究

稀土微肥在农业上的应用多有报道。本文通过试验研究,获得最佳使用量为每50公斤干料加入18克稀土微肥,对平菇的生产有显著的增产效果。     

Intranuclear localization of mercury in vivo

Purified nuclei isolated from mice challenged with nonlethal levels of mercury chloride (10-(3)M) in drinking water for 4 to 7 weeks (experimental) and from animals given deionized water (control) were fractionated and the subsequent fractions were analyzed for mercury by flameless atomic absorption. Control (active) euchromatin contained 1.75 +/- 0.53 micrograms of mercury per milligram of DNA. There was a 12- to 15-fold enrichment of mercury in the euchromatin fraction of challenged animals. Mercury was not detected in control (inactive) heterochromatin, and only trace levels (parts per billion) appeared in experimental heterochromatin. It seems likely that mercury can be incorporated into chromatin as a metal-protein complex, but the possibility of protein-mercury-DNA or mercury-DNA complexes within euchromatin cannot be excluded.     

流动注射-冷原子吸收法测定大百合中的痕量汞

探讨了流动注射还原气化-冷原子吸收光谱法测定微量汞的最佳条件,建立了大百合中痕量汞的流动注射还原气化-冷原子吸收光谱分析方法,并对检测条件进行了优化。结果表明,该方法操作简便、快速、灵敏度和自动化程度高,测定汞的线性范围为O～80μg/L,相对标准偏差小于3．0％,加标回收率为95％～106％。     

微量元素水溶肥料对大豆生物学性状及产量的影响

以大豆品种高丰1号为试材,采用田间试验方法研究了微量元素水溶肥料对大豆生物学性状及产量的影响。结果表明：微量元素水溶肥料对植株密度、单株分枝数、单株有效荚数、百粒重、单荚粒数都有显著影响。分别比常规对照和清水对照增产7.0%、23.8%,达到了显著和极显著差异,可进一步示范应用。     

Mercury vapor concentrations inside buildings

The concentrations of elemental gaseous mercury in several homes, offices, and laboratories in the Dallas area have been measured. The values are substantially higher than the ambient natural background concentration, about 3 nanograms of mercury per cubic meter of air in San Francisco, Dallas, and Washington, D.C.     

El chichon: composition of plume gases and particles

Aircraft measurements were made of trace gases, atmospheric particles, and condensed acid volatiles in the plume of El Chichón volcano, Chiapas, Mexico, in November 1982. Hydrogen sulfide was the primary gaseous sulfur species in the plume at the time of collection. Concentrations of 28 elements were determined by neutron activation analysis of particulate material from the plume. Rates of trace element emission to the atmosphere for each species were estimated by normlization to the simultaneously determined total sulfur emission rate. The volatile elements sulfur, chlorine, arsenic, selenium, bromine, antimony, iodine, tungsten, and mercury were enriched relative to bulk pyroclastic material by factors of 60 to 20,000. Arsenic, antimony, and selenium were associated predominantly with small (>/= 3 micrometer) particles. Calcium and sodium were present almost exclusively on larger particles and aluminum and manganese were bimodally distributed. Ashladen particulate material injected into the stratosphere during the early violent eruptions was enriched by factors of 10 to 30 relative to ash in some of the same elements observed in the quiescent plume.     

Ethyl mercury p-toluene sulfonanilide: lethal and reproductive effects on pheasants

Ethyl mercury p-toluene sulfonanilide (active ingredient of Ceresan M) at a dietary concentration of 30 parts per million (12.5 parts of mercury per million) was lethal to adult ring-necked pheasants. Egg production and survival of third-week embryos were sharply reduced when breeders were maintained on feed containing 10 parts of this compound per million (4.2 parts of mercury per million).     

快速检测痕量汞的光电型传感方法的建立

为建立一种检测痕量汞的光电型传感方法,利用汞抑制葡萄糖氧化酶体系(即葡萄糖氧化酶—辣根过氧化物酶-葡萄糖-邻联甲苯胺—偶联反应体系)生成蓝色产物的原理,将Glu与OT固定化制成试纸条,插入自制的便携式光电型传感器,绘制出汞离子溶液浓度与对应的反射光强度值的标准曲线。实验结果表明,当汞溶液的浓度范围分别处于0.010～0.050mmoL/L时,光反射强度值与汞浓度皆呈现良好线性关系。经优化检测条件,汞溶液与双酶孵育的最佳时间为1h。该方法测定汞的检出限为1.0×10-4 mmol/L,检测时间分别为5min。由此可知,此方法检测汞快速、简便,有望实现对样品中汞含量的现场检测。     

土壤中汞的检测-氢化物发生原子荧光法

采用盐酸—硝酸消化—原子荧光光谱法检测土壤样品中汞的含量,选择了仪器工作参数;研究了载气流速、硼氢化钾浓度等测试条件对检测的影响;分析了土壤标准样。结果表明:原子荧光法具有数据准确、精密度高、简便、高效、适用性强的特点,可用于土壤中微量汞的检测。     

基体改进剂对重楼中砷·汞含量测定的影响

[目的]探讨重楼中微量元素砷、汞含量的测定方法,为重楼药材毒副作用评价体系提供参考。[方法]采用石墨炉原子吸收光谱法（GFAAS）,通过对基体改进剂硝酸镍、氯化钯的用量,酸性介质,灰化温度,原子化温度等试验参数进行优化,探索了基体改进剂对重楼中砷、汞含量测定的影响。[结果]加入硝酸镍、氯化钯不仅能提高砷、汞的灰化温度和原子化温度,还能提高测定的灵敏度和精密度,且重现性好。[结论]加入基体改进剂的方法快速、可靠,为重楼中砷、汞含量测定提供了一种简便有效的方法。     

Environmental mercury: rapid determination in water at nanogram levels

Mercury compounds and free mercury are determined by emission spectrophotometry in a radiofrequency helium plasma. The method is simple, rapid, directly applicable to environmental water samples, and subject to few interferences. The useful working range is 10 nanograms to 10 micrograms, or 1 part per billion to 1 part per million in 10 milliliters of sample. The limit of detection is about 2 nanograms.     

叶面肥和表面活性剂对辣椒表皮百菌清的光化学降解的影响

[目的]探究叶面肥和表面活性剂对辣椒表皮百菌清的光化学降解的影响。[方法]以高压汞灯为光源,在辣椒表面定量添加百菌清,研究叶面肥(叶面微肥和叶面氮肥)和3种不同类型的表面活性剂(十二烷基苯磺酸钠、吐温-80和十六烷基三甲基溴化铵)对百菌清在辣椒表皮光化学降解的影响。[结果]在高压汞灯下,按推荐剂量添加的叶面微肥和叶面氮肥对百菌清的光化学降解都有强烈的光猝灭作用,光猝灭率分别为89.5%和174.6%。添加十二烷基苯磺酸钠和吐温-80对百菌清的光化学降解均具有光敏作用,光解半衰期T1/2分别为2.23和4.30 h;添加十六烷基三甲基溴化铵对百菌清的光化学降解具有光猝灭作用,光解半衰期T1/2为7.10 h。[结论]为实际农业生产选择肥料农药及研究百菌清在环境中转化及归趋提供了理论依据。     

协同催化光度法测定环境水样中痕量汞研究

研究在酸性介质中,超痕量汞能催化溴酸钾和过氧化氢协同氧化偶氮胂Ⅰ褪色,褪色程度与汞的含量在一定范围内呈线性关系。结果表明,方法检出限为7.26×10-10 g.mL-1,褪色程度与汞的含量在0～6.5μg.mL-1范围内符合比耳定律,建立了测定痕量汞的催化分光光度法。该方法测定环境废水中痕量汞的含量,结果满意。     

A budget for continental growth and denudation

Oceanic crustal material on a global scale is re-created every 110 million years. From the data presented it is inferred that potential sialic material is formed at a rate of about 1.35 cubic kilometers per year, including hemipelagic volcanic sediments that accumulate at a rate of about 0.05 cubic kilometer per year. It is estimated that the influx of 1.65 cubic kilometers per year of terrigenous and biogenic sediment is deposited on the deep ocean, and this represents continental denudation. Because all this material is brought into a subduction zone, continental accretion rates, which could include all this material, may be as high as 3.0 cubic kilometers per year with a potential net growth for continents of 1.35 cubic kilometers per year.     

AFS法快速测定茶叶中Hg、As和Se的方法研究

[目的]为AFS法测定茶叶微量元素的推广与应用提供理论依据。[方法]准确称取研磨碎的各种茶叶粉末1.00 g,用10 ml混合酸(HNO3-HClO4)预处理,用电热板加热消解和烘箱加热消解两种不同的方法消解茶叶,用连续流动进样-氢化物发生原子吸收荧光光谱法(AFS)同时测定茶叶中有害元素As、Hg和有益元素Se。并对消解温度、消解试剂用量、消解程序设计、消解时间等消解条件进行优化。[结果]在测试样品中添加适量的Hg、As和Se标准溶液,按样品测定的全过程进行测定时,As的回收率为113.3%,Hg的回收率为115.0%,Se的回收率为92.5%。[结论]AFS法可满足同时测定茶叶中Hg、AsS、e等多种微量元素的需要,且测定的精密度与准确度都较高,快捷简便,有助于推广。     

Mercury compounds reduce photosynthesis by plankton

Concentrations of organomercurial fungicides as low as 0.1 part per billion in water reduced photosynthesis and growth in laboratory cultures of one species of marine diatom and several natural phytoplankton communities from Florida lakes. The acute toxicity of mercury compounds to phytoplankton is dependent on the chemical nature of the mercury compound and on cell concentrations.     

改性生物炭对汞污染土壤绿豆生长及汞含量的影响

为了探究改性生物炭对于汞污染地区植株生长的影响,通过盆栽试验研究了施用不同比例改性生物炭对于汞污染土壤绿豆生物量、汞含量、微量元素和酶活性的影响。试验共设4个处理：不施加改性生物炭(CK);施加0.67%土质量的改性生物炭(C-10);施加2.00%土质量的生物炭(C-30);施加3.33%土质量的改性生物炭(C-50)。结果表明：施加改性生物炭后绿豆各器官生物量均有不同程度的增加,其中以C-30处理效果最佳,根、茎、叶、果实的干生物量增幅分别达到7.04%、40.86%、33.33%和52.76%;各器官汞含量显著降低,其中以C-50处理效果最佳,根、茎、叶、果实中的汞含量降幅分别达到74.34%、86.02%、70.66%和84.93%;C-30和C-50处理果实汞含量分别降低了83.56%与84.93%,远低于国标食品中总汞限量标准0.020mg·kg^-1,达到可食用标准;C-30处理较为显著的促进了植株的生长发育,提高了可食用部分的品质与微量元素含量;施加生物炭后叶片酶活性表现出低促高抑的趋势,过氧化物酶(POD)和过氧化氢酶(CAT)的酶活性均在C-30...     

Mercury monitor for ambient air

An isotope-shift, Zeeman-effect atomic absorption spectrometer has been demonstrated to have sufficient sensitivity to continuously monitor the total mercury content of ambient air. At present, the minimum total mercury concentration detectable with this device is 0.2 microgram per cubic meter of air-one fifth of the proposed federal guideline. This is the first technique which responds to both mercury vapor and mercury in particulates available for continuous monitoring at this concentration.     

Fossil fuels as a source of mercury pollution

The upper limit of the quantity of mercury released by weathering processes is approximately 230 metric tons per year. The quantity of mercury released by burning of coal is estimated to be of the order of 3000 tons per year, a quantity comparable to that emitted as waste from industrial processes.     

氢化物-原子荧光法测定5种补益中药中的汞·砷·铋

[目的]建立常用的5种补益中药——党参、黄芪、当归、龙眼肉、拘杞子中Hg、As和Bi 3种痕量有害元素含量分析的方法。[方法]采用氢化物-原子荧光法测定党参、黄芪、当归、枸杞子、龙眼肉5种补益中药中Hg、As和Bi的含量。[结果]采用湿法消化样品,以硫脲-KBH4-HCl为反应测定体系,在最佳测定条件下,检出限分别为Hg0．15μg/L、As 0．18μg/L、Bi 0．12μg/L。线性范围分别为№0～25．0μg/L、As 0—120．0μg/L、Bi 0～20．0μg/L,加标回收率在96．5％～104．5％。[结论]该法可同时快速、简便、准确地测定5种补益中药中Hg、As和Bi的含量。