Invader amphipods Gmelinoides fasciatus (Stebbing, 1899) inhabiting distant waterbodies demonstrate differences in tolerance and energy metabolism under elevated temperatures

Gmelinoides fasciatus is a successful invasive amphipod (Amphipoda, Crustacea) that dispersed from Lake Baikal to various waterbodies. Here we studied whether Baikal conditions are optimal for G. fasciatus in terms of thermotolerance and investigated lethal temperatures, 70 kDa heat shock protein level, energy metabolism, and antioxidant defense of animals from three geographically distant waterbodies under changing temperatures. We used acute heat exposure to 28 °C to assess the median lethal times and gradual temperature increase from 6 °C to determine the lethal temperatures. Mortality under heat shock was explainable by the baseline content of Hsp70 that correlated with thermal history. But it was not the case under gradual temperature increase where Hsp70 levels became similar and the mortality pattern changed. The most thermotolerant amphipods from the Gulf of Finland demonstrated a higher amount of free glucose during the temperature increase that may be related to the higher salinity of this waterbody and less energy required for ion regulation. Even though concentrations of major physiological ions in Lake Baikal are lower than in Lake Ladoga, G. fasciatus from Ladoga was slightly more sensitive to the gradual temperature increase. This difference could be explained by the influence of high levels of humic and other potentially toxic substances in Lake Ladoga indicated by increased activities of catalase and glutathione S-transferase. Importantly, all G. fasciatus populations accumulated relatively low levels of lactate during the temperature increase, which may reflect the ability of this invasive species to effectively maintain aerobic metabolism under various conditions.     

影响聚合物段塞流变性因素的研究

本文针对我国表面活性剂/聚合物驱油的实际,研究了石油磺酸盐(PS)、正丁醇(R_4OH)和矿化水对水解聚丙烯酰胺(HPAM)溶液流变性的影响。结果表明,PS对HPAM溶液流变性的影响与介质的矿化度有关:非矿化水介质中,PS对HPAM溶液性质的影响类似于无机盐,能降低HPAM溶液的表现粘度(η_α)和稠度系数(k);当系统中含有一定浓度矿化水时,PS却能升高系统的η_α和k值,降低流型指数(n),使系统的非牛顿性增强。在含有PS和矿化水的HPAM系统中加入R_4OH,系统的η_α和k值会有所增加。     

基于粒子群优化RBF神经网络原油含水率预测

原油含水率预测对于确定油井水、油层位以及估计原油产量有着非常重要意义。BP神经网络是最近常用的原油含水率预测方法,然而,由于BP神经网络存在容易陷入局部极小值、收敛速度慢等问题,影响了其预测的实用性和准确性,对此,提出基于粒子群优化RBF神经网络(PSO-RBFNN)的原油含水率预测方法,粒子群优化算法用于RBF神经网络参数优化。在分析原油含水率预测的影响因素基础上,建立粒子群优化RBF神经网络的原油含水率预测模型。实验结果表明,在原油含水率预测中,基于粒子群优化RBF神经网络比BP神经网络有着更高的预测精度。     

Gamma-ray remote sensing of aeolian salt sources in the Murray-Darling Basin, Australia

This paper presents a new technique for mapping regional salt sources that has major implications for salinity management in southeastern Australia. This was achieved by analyzing a regional mosaic of airborne gamma-ray emission derivatives and verified by existing airborne electromagnetic and drilling data. A significant correlation was found between aeolian (windblown) materials, upland salts and gamma-ray signatures. This is consistent with the conceptual model that much of the salt in the upland areas of the Murray-Darling Basin is sourced from deposited aeolian materials that have been derived from deflationary events in salt-bearing landscapes in the western arid part of the basin. From gamma-ray emissions, and based on an observed relationship with borehole salinity, concentrated aeolian salt source deposits contained about 0.7% potassium and 10 ppm thorium. Using this signature on normalized data, an Euclidean distance algorithm provided mapping and information relating to salt-mobility pathways over a wide region. The resulting gamma-ray salt source model (GSM) facilitates focussed management of salinity infiltration zones in catchments across the basin.     

Effect of different substrate concentrations and salinity on hydrogen production from mariculture organic waste (MOW)

In this paper, the influence of substrate concentrations and salinity on hydrogen production from mariculture organic waste (MOW) at mesophilic condition in batch reactors was determined. It was found that the hydrogen yield and hydrogen content were influenced by the initial substrate concentrations and salinity. The optimum concentration for hydrogen production was 20 g/L. The salinity could produce inhibit effect for hydrogen production. The low hydrogen content was detected at high salinity condition. The nutrients changing and metabolites composition could also be significantly influenced by the salinity. The releasing of carbohydrate from MOW could be easily used for hydrogen production, and protein could be accumulated and assimilated during the hydrogen fermentation. The enhancing of salinity was disadvantage for total metabolites accumulation.     

Nonionic surfactants from poly(ethylene terephthalate) waste: II. Effect of temperature,salinity, pH-value,and solvents on the demulsification efficiency

The effect of temperature, NaCl concentration (salinity), pH-value, and solvents on the demulsification efficiency of the demulsifiers synthesized from poly(ethylene terephthalate) waste [polyoxyethylenated glycolized product of PET (POGP)] in breaking synthetic water-in-benzene emulsions stabilized by petroleum asphaltenes have been investigated. The demulsification efficiency of the studied polymeric surfactants was found to increase as the temperature was raised and the salinity of the aqueous phase decreased. Neutral pH-value of the aqueous phase of the emulsion was found to be the optimum value causing maximum demulsification efficiency. Water and 1, 2 propylene glycol were found to be the best solvents for the prepared demulsifiers offering maximum demulsification efficacy.     

On the issue of limiting nutrient and predictions of cyanobacteria in aquatic systems

This study aims at bridging the gap between freshwater and marine eutrophication studies by presenting (1) a cross-system analysis of the relationship between chlorophyll and the total nitrogen (TN) to total phosphorus (TP) ratio (2) a general model to predict concentrations of cyanobacteria from data on TP, the TN/TP ratio, salinity and temperature, and (3) a general trophic level classification for aquatic systems based on chlorophyll classes (for oligo-, meso-, eu- and hypertrophic systems). The data compiled in this study concerns more than 500 lakes and coastal areas covering a very wide domain in terms of nutrient concentrations and salinity. There was no simple relationship between the TN/TP ratio and empirical chlorophyll concentrations or concentrations of cyanobacteria. Variations in TP rather than TN generally seem to be more important to predict variations among systems in chlorophyll-a and cyanobacteria. Different "bioavailable" forms of the nutrients (DIN, DIP, phosphate, nitrate, etc.) have been shown to have very high coefficients of variation (CV), which means that many samples are needed to obtain reliable empirical data which are necessary in models aiming for high predictive power and practical usefulness.     

SIM—1气举井固体缓蚀剂的研究与应用

高矿化度的弱酸性采出水中的CO2引起了文东油田高含水气举采油井生产管柱的严重腐蚀,研制了固体状缓释性酰胺咪唑啉缓蚀剂SIM－1（有效成分75％）,简要介绍了制备过程。室内评价表明：①直径40mm、长400mm的园柱体60℃时在油田采出水中的溶解时间,在静止水中大于15天,在流动水中大于5天。②在60℃的常压CO2饱和3％NaCl溶液中,50－100mg/L的SIM－1可有效地保护A3、N80和J55钢材。③SIM－1与油基清蜡剂配伍。④电化学测试表明SIM－1为控制阳极过程为主的混合型蚀 剂。在文东油11口气举井试用,SIM－1缓蚀剂投入井底,使其在采出液中浓度维持在100mg/L左右,投加周期为21－35天。第一周期末,井口采出水含铁平均由193mg/L降到76.9mg／L,对N80钢的腐蚀速度平均由0.7892mm/a降到0.02162mm/a,井筒挂环腐蚀速率（一口井）由0.8944mm/a降到0.07300mm/a。     

气藏凝析水引起的地层水矿化度淡化问题——以四川盆地新场气田须二段气藏为例

前人据研究成果提出了高温高压气藏地层水矿化度变化较大的认识,由此有可能得出与实际情况不一致的结论,其主要原因是忽视了低矿化度凝析水的影响。为此,利用四川盆地新场气田须家河组二段气藏投产以来获得的产出水样矿化度资料,研究了不同水气比阶段的井口水样矿化度特征,认为井口产出水样矿化度明显受到了凝析水淡化的影响,气藏井口产出水可以划分为凝析水、地层水及其两者的混合水。研究结果表明：①井口产出水矿化度随气井水气比增大而增高,由低矿化度凝析水向高矿化度地层水转变;②当气井水气比小于0.1 m³/10⁴ m³时,井口产出水为矿化度小于1 g/L的凝析水;③当水气比为0.1～0.8 m³/10⁴ m³时,水样矿化度介于凝析水和地层水之间,水样以混合水为主;④气井水气比大于等于0.8 m³/10⁴ m³时,水样最接近于地层水矿化度,凝析水对水样矿化度的影响可以忽略;⑤在排除凝析水淡化影响后,单一气藏地层水矿化度差异不大,新场气田须二段气藏变化范围在93.47～120.05 g/L之间。     

Development of GIS-Based Model to Estimate Relative Reductions in Crop Yield due to Salinity and Waterlogging

A model is introduced that utilizes geographic information systems (GIS) to predict relative reductions in crop yield due to salinity and waterlogging at a field-scale by incorporating spatially and temporally variable crop, climatic, and irrigation data to simulate crop yields. This model utilizes soil and water data commonly collected in field-scale studies. The model’s algorithms are integrated into a GIS (ARCVIEW 3.2) as an extension. The result is a model that does not require extraordinary data collection but will provide practical insight into the spatial effects of salinity and waterlogging on crop yields.