钙钛矿（ABX3）型结构畸变的几何描述及其应用

本文讨论了钙钛矿型 (ABX3型 )化合物的容忍因子 (tolerance factor)、八面体扭转 (octahedraltilting)和体积参数 (global param eterization method,缩写为 GPM)等几何参数与钙钛矿型结构及其畸变结构之间的关系 ,并在此基础上对钙钛矿 Yb Ni O3的晶体结构以及钙钛矿 Mg Si O3和 Sc Al O3在压力下的结构变化分别进行了理论预测。预测结果与实验结果基本一致     

Multi-Objective Fuzzy Optimum Design Based on Reliability for Offshore Jacket Platforms

In consideration of the fuzzy constraint boundary and through analysis of structural reliability, a model of structural fuzzy optimum design is established based on reliability for offshore jacket platforms. According to the characteristics of offshore jacket platforms, the tolerance coefficient of the constraint boundary is determined with the fuzzy optimization method. The optimum level cut set which is the intersection of the fuzzy constraint set and fuzzy objective set, is determined with the bound search method, and then the fuzzy optimum solution to the fuzzy optimization problem is obtained. The central offshore platform SZ36-1 is designed with the fuzzy optimum model based on reliability; the results are compared with those from deterministic optimum design and fuzzy optimum design. The tendency of design variables in the above three methods and its reasons are analyzed. The results of an example show that the fuzzy optimum design based on reliability is stable and reliable.     

Assessing the potential for satellite image monitoring of seagrass thermal dynamics: for inter- and shallow sub-tidal seagrasses in the inshore Great Barrier Reef World Heritage Area,Australia

Seagrass meadows are at increasing risk of thermal stress and recent work has shown that water temperature around seagrass meadows could be used as an indicator for seagrass condition. Satellite thermal data have not been linked to the thermal properties of seagrass meadows. This work assessed the covariation between 20 in situ average daily temperature logger measurement sites in tropical seagrass meadows and satellite derived daytime SST (sea surface temperature) from the daytime MODIS and Landsat sensors along the Great Barrier Reef coast in Australia. Statistically significant (R²?=?0.787–0.939) positive covariations were found between in situ seagrass logger temperatures and MODIS SST temperature and Landsat sensor temperatures at all sites along the reef. The MODIS SST were consistently higher than in situ temperature at the majority of the sites, possibly due to the sensor’s larger pixel size and location offset from field sites. Landsat thermal data were lower than field-measured SST, due to differences in measurement scales and times. When refined significantly and tested over larger areas, this approach could be used to monitor seagrass health over large (10⁶?km²) areas in a similar manner to using satellite SST for predicting thermal stress for corals.     

咸水灌溉对黄河蜜瓜产量和品质的影响

分析了不同矿化度(0.8 g·L^-1、2 g·L^-1和5 g·L^-1)灌溉水灌溉对黄河蜜瓜产量、作物抗性和果实品质的影响.结果表明:随着灌溉水矿化度的增加,作物耗水量逐渐降低,间苗后第49天之前耗水量明显降低,但随着高矿化度水持续使用,耗水量在定植后第49天有所增加;作物叶面积指数和叶面积持续时间不断降低;果实上市产量不断降低,但果实个数没有明显变化;收获指数不断增加;果实的可溶物总量明显增加;单个果实的种子数量明显增加;果实形状指数明显增加,灌溉水矿化度越高瓜形越接近球形.土壤电导率超过2.7 dS·m^-1时每增加单位土壤电导率作物总产量降低12.7%.     

热休克蛋白研究进展

热休克蛋白是生物体在不利环境因素刺激下应激合成的一族进化上高度保守的蛋白质。综述了热休克蛋白在热休克因子和热休克元件调节下的基因表达调控,并讨论了热休克蛋白的生物学功能和它们在海洋生物养殖方面潜在的应用意义。     

马铃薯不同品种耐盐性差异初步研究

马铃薯是世界上一种重要的粮食作物。本项试验目的是为了就6个马铃薯品种对盐胁迫的生长反应和耐盐性差异进行比较研究。根据试验结果, 马铃薯是一种对盐分很敏感的作物, 高盐分(EC12.0ds/m)处理使植株高度、生物量、产量严重下降, 而低盐分(EC4.0dS/m)和中盐分(EC8.0ds/m)处理则由于品种的不同各显示出差异。由产量和生物量确定6个品种的耐盐顺序为: V-3>Mariva>Piratini>CFC-69.1>CEW-69.1>Muziranzara, V-3和Mariva推荐为进一步实验品种。     

赤潮藻类温度生态幅的定量表达模型研究赤潮藻类温度生态幅的定量表达模型研究

首先在Moisan的温度和比生长率关系基础上,依据Shelford耐受性定律,建立了赤潮藻类温度生态幅(最适温度、适温范围、耐受范围)的定量表达模型。同时,依据此模型可定量导出赤潮藻类的生物学零度。其次,结合实验培养数据,建立了东海原甲藻比生长率的温度响应模式,并利用研究结果定量得到该藻种的温度生态幅,这与已有的实验研究和现场监测结果有较好的一致性。     

Fate of the Black Sea Acartia clausi and Acartia tonsa (Copepoda) penetrating into the Marmara Sea through the Bosphorus

In October 2005 spatial distribution of live and dead Acartia clausi and Acartia tonsa was studied in the Black and Marmara Seas and near the Marmara Sea inlet of the Bosphorus, in order to understand their fate upon transportation between two seas. The morphometric characteristics in both species from all studied areas, and the decreased abundance of A. clausi and A. tonsa from the Black Sea towards the Marmara Sea indicate that the Marmara Sea Acartia populations are formed by recruitment from the Black Sea. We observed mass mortality of A. clausi in the Marmara Sea near the Prince Islands. The majority of carcasses (66% of total A. clausi numbers in the Marmara Sea) were found in the salinity gradient layer.     

High-sediment tolerance in the reef coral Turbinaria mesenterina from the inner Great Barrier Reef lagoon (Australia)

Sedimentation is an important stressor on coral reefs subjected to run-off, dredging and resuspension events. Reefs with a history of high-sediment loads tend to be dominated by a few tolerant coral species. A key question is whether such species live close to their tolerance thresholds or near their niche optima. Here, we analyse experimentally the sediment tolerance of a spatially dominant coral, Turbinaria mesenterina (Dendrophylliidae), at nearshore reefs in the central Great Barrier Reef lagoon. Testing was conducted in a 5-week tank experiment under manipulated sediment loading and flow conditions. Physiological stress was assessed based on the behaviour of three key response variables: skeletal growth rate, energy reserves (lipid content) and photosynthetic performance. Because sediment effects are likely to vary between flow regimes, sediment and flow responses were tested using a full factorial design. Sediment loads greater than 110 mg cm⁻² had no effect on any of the physiological variables, regardless of flow (0.7–24 cm s⁻¹). Turbinaria mesenterina is thus tolerant to sediment loads an order of magnitude higher than most severe sediment conditions in situ. Likely mechanisms for such tolerance are that: (1) colonies covered in sediment (60–120 μm) in low-flow were able to clear themselves rapidly (within 4–5 h); and (2) sediment provides a source of food. These results suggest that intensified sediment regimes on coastal reefs may shift coral communities towards dominance by a few well-adapted species.     

芽孢对提高好氧颗粒污泥环境耐受力的作用

为研究好氧颗粒污泥中大量存在的芽孢对其环境耐受力的作用,将好氧颗粒污泥经过低温无营养、高温高压、冷冻和紫外线处理后,监测其活性恢复过程中2,6-吡啶二羧酸根(dpa)的释放、比耗氧速率(SOUR)和以还原2,3,5-氯化三苯基四氮唑(TTC)为标志的脱氢酶的活性变化.实验结果显示,好氧颗粒污泥中大量存在的芽孢在不良环境条件下处于休眠状态,环境条件改善后能迅速转化为繁殖体细胞,进行正常的代谢活动.作为潜在的生命力,好氧颗粒污泥对不良环境的耐受力增强.芽孢是好氧颗粒污泥不容忽视的重要组分.