2009年罗源湾表层海水DIN与TN及PO4-P与TP浓度换算系数的研究

为解决海湾入海污染物总量控制中氮磷污染源强统计指标与海水水质标准因子不同的问题,本研究以罗源湾为例,采用现场调查取样和实验室分析结合的方法,通过分析罗源湾表层海水中的CDIN/CTN和CPO4-P/CTP的比值,将海水中DIN与PO4-P浓度的标准值转换成TN与TP的浓度.研究结果表明2009年罗源湾表层海水中的CDIN/CTN和CPO4-P/CTP的比值范围分别为0.12～0.97和0.16～0.91;其中夏季最低,CDIN/CTN和CPO4-P/CTP的比值平均为0.23和0.41,CDIN/CTN比值平面分布上呈湾顶和湾中部低、湾口高的分布趋势,CPO4-P/CTP比值平面分布上呈湾顶至湾口逐步递增的变化趋势;冬季最高,CDIN/CTN和CPO4-P/CTP的比值平均为0.67和0.68,CDIN/CTN比值平面分布上呈湾顶和湾口低、湾中部高的分布趋势,CPO4-P/CTP比值平面分布则相反;年均DIN和TN的浓度换算系数为0.48,PO4-P和TP的浓度换算系数为0.55;与其他海域相比,河口型海湾比值总体较高,沿岸海湾高于近海海域.     

Seasonal radiocarbon reservoir ages for the 17th century James River,Virginia estuary

This study utilizes a combined stable isotope and ¹⁴C dating approach to determine the radiocarbon reservoir age correction, ΔR, for the James River, Virginia estuary from 17th century Crassostrea virginica shells of known collection dates. ΔR, which can vary spatially and temporally, is a locality-specific adjustment applied to the global ocean reservoir, R, to further account for the offset between the atmospheric and marine ¹⁴C calibration curves. To assess the temporal variability in ΔR, continuous δ¹⁸O sampling along the oyster shell hinge provides a seasonal record throughout the oyster's life. This is then used to identify sampling locations for ¹⁴C measurements based on calcite precipitated during the Summer (>19 °C) and Fall through Spring (F-Sp, <15 °C) months. The resulting seasonal ΔR values range from −151 ± 46 to +109 ± 55 ¹⁴C years (260 years) due to changes in the contribution and age of dissolved inorganic carbon (DIC) from marine and freshwater sources in the James River estuary. The F-Sp samples display a larger ΔR range than the Summer samples, as do the shells precipitated during drought conditions (1606–1612) when compared to shells from the remainder of the 17th century. The largest intrashell ΔR variability, 195 ¹⁴C years, is similarly found in a drought shell and is attributed to variability caused by the extreme regional 1606–1612 drought. Early land use changes related to European development and farming practices also altered the age of DIC in the James River estuary. We estimate that the soil inorganic carbon (SIC) contributing to freshwater DIC ranged from 0 to ∼1800 years old and reflected both the drought and land use changes that occurred during the 17th century. Using only the Summer samples, which represent the majority of shell calcite, we obtain a mean ΔR = −32 ± 11 ¹⁴C years (1σ) for 17th century James River estuary ΔR at the very onset of European colonization. Employing a seasonally resolved sampling method will provide the greatest constraint on ¹⁴C measurements in an estuarine environment where multiple carbon sources can fluctuate on seasonal timescales and as a result of large scale environmental change.     

龙滩水库溶解无机碳来源及变化特征

河流在碳的运输过程中扮演着重要角色。为探究河流筑坝拦截后龙滩水库溶解无机碳(DIC)的来源和变化特征,于2016年7月和2017年1月采集水样,然后分析了河水DIC及其碳稳定同位素(δ13C)值。研究结果表明:(1)δ13CDIC值具有显著的时空差异,表明两个季节影响DIC的主要因素和DIC的来源并不相同。雨季,DIC及其δ13C主要分布在2.04~4.12 mmol·L^-1和-5.52‰^-2.87‰的范围内;旱季,水体DIC为3.33~4.61 mmol·L^-1,而δ13CDIC显著低于雨季为-15.90‰^-9.12‰。雨季,稀释效应显著降低了DIC浓度,由于水体热分层使得DIC在水柱剖面上差异显著,而旱季由于混合作用的影响,在剖面上差异较低。(2)在雨季,河流δ13CDIC较旱季明显偏正,碳酸盐岩的强烈风化输入大量HCO3-是DIC的主要来源。在旱季,DIC和δ13CDIC成反比关系,δ13CDIC在旱季变得更低,其大部分的DIC来自于土壤CO2输入和原位有机呼吸作用。旱季水体热分层消失,混合作用使得底部具有较低δ13C值的含碳水体上涌,并与表水层混合导致其δ13CDIC值低于雨季。这种季节性模式与自然河流不同,而是与湖泊的季节变化特征更为类似,说明河流拦截蓄水后逐渐湖沼化,并显著影响了DIC的循环。     

钦州湾磷营养状态与浮游植物的碱性磷酸酶活性分析

碱性磷酸酶(Alkaline phosphatase,AP)是浮游植物在磷胁迫的情况下诱导表达的一种酶,其作用是能够将溶解有机磷(Dissolved organic phosphate,DOP)水解成浮游植物可以直接利用的正磷酸盐形式,因此碱性磷酸酶活性(Alkaline phosphatase activity,APA)可用来指示海区浮游植物的磷胁迫状态。本研究以2015-2016年钦州湾4个航次(春季、夏季、秋季、冬季)的调查资料为依据,研究了钦州湾海域表层无机及有机磷的空间分布特征、APA的分布及其与磷营养之间的调控关系。调查期间,钦州湾海域春季、夏、秋、冬的单位叶绿素APA的平均值分别为20.42±5.32 nmol/μg Chl a/h,138.17±94.32 nmol/μg Chl a/h,142.60±72.60 nmol/μg Chl a/h和29.48±18.52 nmol/μg Chl a/h。经分析,APA与无机磷之间存在显著的负相关(P0.05),与N/P呈极显著负相关(P0.01),该海区APA可以反映钦州湾浮游植物的磷胁迫水平。海区氮磷比平均值在除春季外的三个季节均高于35,存在潜在的磷限制,浮游植物在夏季和秋季遭受较严重的磷胁迫。夏季和秋季浮游植物大量表达AP,由此推测DOP可能在钦州湾浮游植物生物量的维持甚至赤潮发生期间的磷补给上起着重要作用。     

Hashin Failure Theory Based Damage Assessment Methodology of Composite Tidal Turbine Blades and Implications for the Blade Design

A damage assessment methodology based on the Hashin failure theory for glass fiber reinforced polymer (GFRP) composite blade is proposed. The typical failure mechanisms including the fiber tension/compression and matrix tension/compression are considered to describe the damage behaviors. To give the flapwise and edgewise loading along the blade span, the Blade Element Momentum Theory (BEMT) is adopted. In conjunction with the hydrodynamic analysis, the structural analysis of the composite blade is cooperatively performed with the Hashin damage model. The damage characteristics of the composite blade, under normal and extreme operational conditions, are comparatively analyzed. Numerical results demonstrate that the matrix tension damage is the most significant failure mode which occurs in the mid-span of the blade. The blade internal configurations including the box-beam, I-beam, left-C beam and right-C beam are compared and analyzed. The GFRP and carbon fiber reinforced polymer (CFRP) are considered and combined. Numerical results show that the I-beam is the best structural type. The structural performance of composite tidal turbine blades could be improved by combining the GFRP and CFRP structure considering the damage and cost-effectiveness synthetically.     

基于切向超滤技术的胶体有机碳和无机氮分离及物源初探

利用切向超滤技术对九龙江口天然水体中胶体相(1 kDa～0. 45μm)、真溶解相(1 kDa)和"溶解相"(0. 45μm)的溶解有机碳和无机氮进行了分离与提取,初步探讨了水环境因子对其理化特性的影响机制,进而探讨了它们的来源和转化.结果表明,切向超滤过程的膜空白和质量平衡符合技术要求;溶解有机碳、亚硝酸盐氮、氨氮、硝酸盐氮和无机氮存在形式以真溶液相(1 kDa)为主,其在胶体相中的质量浓度分别为0. 207～0. 810 mg/dm3、0. 001～1. 870μg/dm3、ND～2. 08μg/dm3、0. 62～79. 30μg/dm3和1. 07～81. 10μg/dm3;胶体态溶解有机碳(COC)含量主要受陆源输入控制.     

温度与溶解态有机磷源对中肋骨条藻生长的影响

为探讨温度与溶解态有机磷（Dissolved organic phosphorus,DOP）对浮游植物生长的共同影响,本文以中肋骨条藻为研究对象,选取含有C-O-P键的三磷酸腺苷（Adenosine triphosphate,ATP）、甘油磷酸钠（Sodium glycerophosphate,SG-P）、6-磷酸葡萄糖（Glucose 6-phosphate,G-6-P）和含有C-P键的草甘膦（Glyphosate,G-P）为不同类型的DOP,检测了4种温度条件下（20、23、26、29℃）藻细胞的生长状况以及培养液中总溶解态磷（Total dissolved phosphorus,TDP）、溶解态无机磷（Dissolved inorganic phosphorus,DIP）浓度与藻细胞内碱性磷酸酶（Alkaline phosphatase,AP）的变化。研究结果表明：含有C-O-P键的ATP、SG-P和G-6-P均能较好地维持中肋骨条藻的生长,并且升温可进一步促进各组藻细胞的生长,最大藻细胞密度分别达到176.7×10⁴、218.8×10⁴和178×10⁴ cell/mL;此外升温还可加速ATP、SG-P和G-6-P组培养液中TDP浓度的下降,以及ATP组培养液中DIP浓度的升高;但各组藻细胞内AP活性在不同温度条件下均处于较低水平（< 10 fmol pNP/（cell· h））。与含有C-O-P键的DOP相比,G-P组的藻细胞在各温度条件下生长密度均较低,最大藻细胞密度仅为40.7×10⁴ cell/mL;但其藻细胞内AP活性显著高于ATP、SG-P和G-6-P组[最高达83 fmol pNP/（cell·h）]且随温度升高而降低。以上结果表明,不同类型DOP会显著影响中肋骨条藻的生长,其中ATP、SG-P和G-6-P能更为有效地被中肋骨条藻生长所利用,并且温度升高（20~29℃）是促进3种DOP条件下中肋骨条藻生长的重要环境因素,但该效应可能并不依赖于AP活性。     

矿物材料学的几个基本问题

１　矿物材料发展的概况矿物材料是由矿物组成的无机非金属材料,有时也称硅酸盐材料;它是利用天然和人造的矿物为原料,经过一定的生产工艺直接利用或加工成具有一定物理化学性能的非金属材料。广义者也包括金属材料。当代材料研究的主要对象是无机非金属材料。我国生产非金属材料和原料的工业,改革开放前是一个处于技术落后、装备不足、队伍拼凑、人才不足的部门。改革开放才使之焕发青春,有了长足的发展。长期以来,我国一直强调金属材料,大力发展冶金工业,“以钢为纲”、“大打钢铁之仗”是长期强调发展冶金工业的口号。在人类已进…     

基于聚二甲基硅氧烷胶与Zn-Al型水滑石复合膜为离子载体的溶解无机碳电极及其性能标定

深海探测溶解无机碳含量异常,可以为寻找热液口提供一个很好的证据。本文设计的基于自制的聚二甲基硅氧烷胶与Zn-Al型水滑石复合膜为离子载体的溶解无机碳探测电极属于电势型电极,适用于对深海中溶解无机碳的测量,具有体积微小、便于与pH、盐度、温度、氧化还原电位等多种传感器集成在同一探头腔内,实施在线探测等优点。实验室条件下,将该溶解无机碳探测电极与银/氯化银参比电极分别接在Keithley 6517A高阻抗电位计输入端进行测试,测试结果表明：该电极对不同浓度的碳酸氢钠溶液具有良好的响应信号,响应时间大约在30s—1 min,检测限在10－1—10－4mol?L–1。     

Correcting the errors from variable sea salt retention and water of hydration in loss on ignition analysis: Implications for studies of estuarine and coastal waters

The standard technique of determining the concentrations of total suspended solids (TSSs), particulate inorganic matter (PIM), and particulate organic matter (POM) by filtration with glass fiber filters is subject to an error or bias from sea salt plus water of hydration retention, when applied to saline waters. The sea salt plus water of hydration retention by the filters occurs even after washing the filter with 300 ml of deionized water, a greater volume than any wash recommended in the literature. We determined that the mass retention on a glass fiber filter, at a given salinity, is essentially constant, no matter the volume of seawater passed through the filter. We also determined that the sea salt plus water of hydration retention on glass fiber filters is directly proportional to the salinity of the seawater filtered. Sea salt plus water of hydration retention causes an overestimate of TSS; sea salt retention causes an overestimate of PIM; volatilization of water of hydration causes an overestimate of POM. Thus a correction curve is required for sea salt and water of hydration errors in the determination of TSS and PIM. Corrected POM comes from the difference between the two. Also, filter blanks (procedural control filters), run with deionized (DI) water rather than the seawater sample, are required to correct for possible filter mass loss during the analysis. We demonstrate correction curves for sea salt plus water of hydration retention for Whatman GF/F filters, 47 mm diameter, utilizing the methods of the APHA Manual, Standard Methods for the Examination of Water and Wastewater. Application of other glass fiber filter types or an analytical technique differing significantly from that employed here requires a different correction curve for retention of sea salt and water of hydration. These methods can be used to reanalyze older data on PIM, POM, and TSS.We apply these corrections to PIM and POM data from the northern Gulf of Mexico and examine the interactions of these filter corrections with corrections for structural water volatilization from suspended clay minerals in the determinations of PIM and POM. We analyze published data on PIM and POM determinations and their application to remote sensing. We conclude that sea salt and water of hydration retention on filters has an adverse effect on remote-sensing algorithms inverting radiance reflectance to estimate concentrations of suspended matter.