山西孙家庄中酸性杂岩体及其邻近地区的找矿远景评价

通过“面型”岩石测量和多子样剖面岩石测量,对山西孙家庄中酸性杂岩体作出找矿远景评价,并对其邻近地段进行矿化追踪。确定该岩体的主要指示元素和伴生元素,圈出以Cu为主的斑岩矿化多元素组合异常,在Cu异常浓集中心发现斑岩矿化。孙家庄岩体周围地区,存在斑岩型矿化—接触交代矿化—热液多金属矿化的环带状分布模式。     

Measurements of Reaction Coefficients of NO2 and HONO on Aerosol Particles

The reaction coefficients of nitrogen dioxide and nitrous acid with monodisperse sodium chloride and ammonium sulphate aerosols have been measured in a flow reactor at atmospheric pressure. These experiments were performed at relative humidities above and below the deliquescence points of both aerosols (r.h. 50 and 85%) at 279 K. The results for NO₂ afford a reaction coefficient in the range (2.8–10) × 10^-4 and for HONO, (2.8–4.6) × 10^-3. For both species, there appears to be an enhancement of the reaction coefficient on sodium chloride aerosol at 50% r.h. The results are compared with reaction coefficients determined by other experimental methods. A good agreement is found for both gases between this method and the coated denuder method previously developed in our research laboratories (Msibi et al., 1993) and with the majority of other published data for NO₂. In the case of HONO, our estimate of reaction coefficient is smaller than, or at the lower limits of the ranges reported by other published studies.     

Fast Oxidation Reaction of Nitrite by Dissolved Oxygen in the Freezing Process in the Tropospheric Aqueous Phase

Nitrite oxidation in the tropospheric aqueous phase by freezing was evaluated by freezing a field sample. Nitrite oxidation by dissolved oxygen in the freezing process is much faster than by other oxidation processes, such as reactions with ozone, hydrogen peroxide or dissolved oxygen in an aqueous solution at pHs 3 to –6. At pH 4.5 and 25°C, the lifetime of nitrite in the aqueous phase is ca. 1 hr in oxidation by ozone (6×10^-10 mol dm^-3), ca. 10 hr in oxidation by H₂O₂ (2×10^-4 mol dm^-3), and 7.5 hr (Fischer and Warneck, 1996) in photodissociation at midday in summer. Under the same conditions at a temperature below 0°C, the lifetime of nitrite in the freezing process is estimated as ca. 2 sec when the droplets are frozen within a second. The reaction by freezing is affected by the presence of salts, such as NaCl or KCl, or orgnaic compounds, such as methanol or acetone. The results of freezing a field rain or fog sample showed that nitrite oxidation proceeds below pH 6, and the conversion ratio of nitrate from nitrite increases with decreasing pH. The oxidation of nitrite by freezing was also observed in freezing fog particles generated by an ultrasonic humidifier. The ratios of the concentrations of ions in the winter sample to those in the summer sample (or those in the fog sample) were almost the same values. However, the concentration of nitrite in the winter sample was lower than that estimated by the ratios of other ions. From the present study, it seems that the freezing process plays an important role in the nitrite sink process in the tropospheric aqueous phase.     

环境因子对2种南极绿藻脂肪含量和脂肪酸组成的影响

通过气相色谱方法对南极冰藻的脂肪酸进行了分析,发现环境因素对2种绿藻总脂含量有一定的影响：(1)温度对Pymmixtomonas sp,总脂含量影响不大,一般为8．3％～8．9％,Chlorophyceae L-4在2℃时的总脂含量最高为10.33％;(2)光强显著地影响这2种绿藻脂肪在细胞内的积累。随着光强由限制生长的39 lx增加到3900 lx,2种绿藻的脂肪酸含量降低：(3)盐度的提高有利于2种绿藻脂肪的积累;(4)营养盐的限制也利于2种绿藻脂肪的积累。在氮源缺乏条件下,Pyramidomonas sp,和Chlorophyceae L-4细胞内脂肪大量积累,含量分别是以NH4Cl为氮源的2．2和3.2倍。环境因素对2种绿藻脂肪酸组成和含量的影响不同,其脂肪含量的改变反映了南极冰藻生长的改变。环境因子能够影响这2种绿藻的脂肪含量,同样也影响到它们的生长。在适合南极冰藻生长的条件下,脂肪酸积累降低;反之,在南极冰藻生长受到限制的条件下,脂肪合成增加。这表明2种绿藻的脂肪含量随生存环境的变化而变化。环境因子同样影响到2种绿藻的脂肪酸组成,尤其是不饱和脂肪酸的组成和含量,但组成和其生长不存在相关性。环境因子(温度、光强、盐度和营养盐)对2种绿藻脂肪酸的测定结果表明,在2种绿藻中,多不饱和脂肪酸的含量高于单不饱和脂肪酸和饱和脂肪酸。因此。这2种绿藻可望为多不饱和脂肪酸的开发利用提供藻种资源。     

火山沉积岩及其矿床研究中伽马测井曲线解释的误区

根据酸性凝灰岩和酸性火山事件粘土岩的自然伽马测井曲线,对当前流传的"沉积岩层的放射性强度(或放射性核素的含量)随泥质含量的增加而增高"的概念和用自然伽马值及经验公式求泥质含量提出质凝。酸性凝灰岩的自然伽马曲线有高异常响应,若解释为泥岩显然是误解,故将沉积岩伽马曲线高异常一律解释为泥岩是片面的。各类火山事件粘土岩的伽马值相差悬殊,但其泥质含量几乎相等,用它们的伽马值计算泥质含量误差甚大。最后对铝土矿层的伽马曲线稍加解释,指出核测井应用的远景。     

低温条件下有机酸对铁、铜的淋滤实验研究

水／岩作用实验研究表明，在低温条件下柠檬酸、草酸和酒石酸对岩石中的铁、铜都有很高的淋滤率。这表明，在表生地质作用过程中有机酸对成矿元素有很强的活化能力。实验研究同时发现，有机酸对成矿元素的活化能力受其分解温度的限制，由于大部分有机酸的分解温度都在２５０℃以下，因而有机酸对成矿元素的活化仅限于低温条件。本次研究还显示，判断一种岩石能否成为矿源层，不能简单的以其中成矿元素的含量高低作为标准，其中更关键的因素是元素在岩石中的存在形式，如果成矿元素在岩石中难以活化的形式存在，那么含量再高也无法提供成矿物质     

Limnology of Opal Lake

Opal Lake, a cold, acid lake on the central volcanic plateau of the North Island, New Zealand, had an average pH of 4.3 and was highly eutrophic. The biota was less diverse than in neighbouring near‐neutral waters. Macrophytes were rare; phytoplankton were mainly represented by the Chlorophyceae, and there were only 4 zooplankton species. The mean standing crop of macroinvertebrates was 6240 per square metre; this was higher than in other eutrophic lakes in the region and comprised more than 98% chironomid larvae represented by 4 species. Molluscs were absent. The fauna was more diverse than in more acid lakes of the .central volcanic plateau.     

中华哲水蚤(Calanus sinicus)个体核酸含量及其对生长状况的指示作用

采用荧光染色法对黄、东海春、秋季中华哲水蚤(Calanus sinicus)个体核酸含量进行了研究,初步探讨了RNA∶DNA比对中华哲水蚤生长状况的指示作用。结果表明,中华哲水蚤在饥饿培养24h后RNA∶DNA比值显著降低;雄性个体RNA含量和RNA∶DNA比值显著低于雌体和C5期幼体;春、秋季(2009年5月和2010年11月)个体RNA含量和RNA∶DNA比值存在显著的空间变化,两者最高值均出现在近岸;两个月份DNA含量相对稳定,在2.5—3.5μg/ind之间;个体RNA含量和RNA:DNA比值与叶绿素之间显著正相关,说明饵料是中华哲水蚤的生长过程中重要的影响因素。     

敞开酸溶-电感耦合等离子体发射光谱法测定石煤钒矿中钒铁铝磷

石煤钒矿资源的勘探、研究和利用均需对其成分进行准确的分析测试,其中钒、铁、铝、磷等主要成分的测定尚未建立标准方法,当前所用的分析测试方法各有不足。采用碱熔电感耦合等离子体发射光谱法(ICP-OES)测定石煤钒矿样品时,高浓度的可溶性盐会导致高背景,干扰测定。酸溶法可避免上述问题,但由于常规的氢氟酸-盐酸-硝酸-高氯酸四酸体系不能消除碳和有机质对样品的吸附和包裹,待测成分无法完全释放,需先将样品高温灼烧除碳,过程繁琐。本文采用少量硫酸加四酸的五酸体系处理样品,电热板加热,盐酸浸提,利用硫酸的强氧化性将样品中大量的碳氧化成二氧化碳,免却了灼烧除碳流程,消除了含碳物质对样品的吸附和包裹,显著增强了消解效果。由此建立了ICP-OES测定石煤钒中钒、铁、铝、磷的分析方法,在称样量为0.1g、浓硫酸加入量为0.30mL时,样品消解率达到99%以上。方法检出限为17~51mg/kg,相对标准偏差(RSD, n=11)在1.7%~5.1%之间;相对误差为-4.6%~2.7%。该方法背景低、测定结果准确,可满足石煤钒矿石样品的检测要求。