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1.
研究了罗源湾海带栽培期间3-5月的水质状况,以及室内海带个体对养殖废水的净化作用.结果表明:大面积海带栽培可改善罗源湾的水质状况,降低无机氮磷含量.3-5月海带栽培区的总无机氮(DIN)的降低率分别达到25.48%、19.62%、44.65%,总无机磷(DIP)的降低率分别为20.17%、32.00%、38.72%.在7 d实验期间,海带个体对养殖废水的净化效果明显,DIN的去除率可达98%以上.海带在养殖废水中能正常生长,保持一定的日增长率,鲜质量及叶片长有所增加.  相似文献   

2.
研究了孔石莼对不同浓度养殖废水的水质净化效果.结果表明,孔石莼对水体中氮、磷营养盐的清除效果明显:对NO3--N、NO2--N、NH4+-N、pO43--P移除率分别可达99.8%、99.6%、95.9%、98.7%;对总无机氮的移除率可达98.6%.孔石莼在吸收氨氮同时对硝态氮和亚硝态氮也有吸收,但NH4+-N的吸收大部分在第1天完成,而NO3--N和NO2--N的大部分吸收需要2d或3d完成.孔石莼在养殖废水中生长良好,鲜质量逐日增加,日生长率均较大.  相似文献   

3.
研究了孔石莼对不同浓度养殖废水的水质净化效果.结果表明,孔石莼对水体中氮、磷营养盐的清除效果明显:对NO3--N、NO2--N、NH4+-N、PO43--P移除率分别可达99.8%、99.6%、95.9%、98.7%;对总无机氮的移除率可达98.6%.孔石莼在吸收氨氮同时对硝态氮和亚硝态氮也有吸收,但NH4+-N的吸收大部分在第1天完成,而NO3--N和NO2--N的大部分吸收需要2 d或3 d完成.孔石莼在养殖废水中生长良好,鲜质量逐日增加,日生长率均较大.  相似文献   

4.
于2003年7月23~29日台风发生期间在广西海洋研究所对虾工厂化养殖基地现场测定养殖水温、pH值和化学耗氧量(COD),采样分析养殖水体的无机氮(DIN)、无机磷(DIP)及叶绿素a(chl.a)含量,并对水温、pH值、COD、DIN、DIP、chl.a间进行相关性分析,研究封闭式工厂化虾养殖生态系中环境因子的变化状况及其影响因素.结果表明:台风气候对该生态系中的水环境因子影响较大,一方面既导致了浮游植物的快速削减,也导致了pH值的明显下降;另一方面又导致了COD的显著增加和DIN、DIP的明显上升.台风期间养成密度大的养殖池中,环境因子之间多具有显著的相关性;养成密度小的养殖池中,环境因子之间的相关性较差.显然,虾池生态系中水环境功能的优劣对对虾的养成质量及抵抗自然灾害具有至关重要的作用,而虾池有机物的及时清除以及水环境因子的适时调控也是重要的一环.  相似文献   

5.
根据福建省生态环境厅发布的2015—2019年近岸海域海水水质监测数据,研究了该海域活性磷酸盐(PO43--P)和无机氮(DIN)的时空分布特征.结果表明,河流径流对闽三角海域营养盐含量的影响存在明显的季节变化特征,表现为枯水期最高,平水期最低的特点;空间分布上呈现出近岸高,向外海逐渐降低的特征,这5年期间营养盐含量呈...  相似文献   

6.
林吓宁 《科技资讯》2014,12(16):231-232
以2013年福建省三沙湾白马港海域的现场调查资料为基础,对该海域叶绿素a和初级生产力的季节分布特征进行了分析和探讨,并对比福建省其它海湾海域(罗源湾、湄洲湾、围头湾)叶绿素a和初级生产力的调查资料。研究结果表明:该海域叶绿素a和初级生产力含量符合春季大于秋季的趋势;该海域叶绿素a和初级生产力含量比福建省其它海湾海域(罗源湾、湄洲湾、围头湾)低;另外,该海域水质中无机氮、磷酸盐含量已达到水体富营养化指标,因此,三沙湾白马港海水水质状况应得到重视。  相似文献   

7.
焦化废水混凝深度处理研究   总被引:3,自引:0,他引:3  
焦化废水来自于炼焦、煤气净化及焦化产品回收过程中产生的废水,其成分复杂多变,属于难处理的工业废水.经生物处理后的焦化废水很难达到相关标准的要求,因此采用混凝法对焦化废水进一步进行深度处理.实验选择了几种混凝剂如聚合硫酸铁(PFS)、硫酸铝(Al2(SO4)3)及聚丙烯酰胺PAM.通过实验确定各种混凝剂处理焦化废水的最佳pH值、最佳投加量、并确定无机混凝剂、有机絮凝剂配合使用时的最佳实验条件.结果表明:不同混凝剂适用的pH值各不相同,最佳的混凝处理条件是PFS和PAM组合,其能进一步去除色度、CODCr,提高出水水质.  相似文献   

8.
以海水养殖废水为培养基质,在膜-光生物反应器(membrane photobioreactor,MPBR)中进行微藻的连续进出水培养,对微藻的生长情况和废水中氮磷营养盐的去除效果进行了研究。首先,将小球藻和衣藻接种于海水养殖废水中进行批次培养,两种微藻均表现出对海水养殖废水较好的适应性,实现了较快生长,比生长速率分别为0.29和0.26 d~(-1)。之后,将小球藻和衣藻分别接种到水力停留时间为1.0 d的MPBR中进行为期32 d的连续进出水培养。小球藻和衣藻的生物量生产速率分别为37.9和32.4 mg·L~(-1)·d~(-1),分别是批次培养中微藻指数生长阶段生物量生产速率的3.4倍和3.6倍。同时MPBR也实现了对海水养殖废水中氮磷营养盐的高效去除,小球藻MPBR和衣藻MPBR在稳定运行阶段对溶解性无机氮(DIN)的平均去除率分别达到93.9%和93.6%,其对溶解性无机磷(DIP)的平均去除率分别达到98.8%和99.0%。可见采用膜法连续培养方法既实现了光生物反应器内微藻的高效培养,同时也实现了对进水中氮磷营养盐的高效去除,另外废水在处理过程中的停留时间相比于传统批次培养得到了极大的缩短,这些都将有利于促进微藻培养方法在水产养殖业的废水处理和循环使用中发挥更大的作用。  相似文献   

9.
哑铃湾网箱养殖区底层水营养盐的分布与评价   总被引:4,自引:0,他引:4  
根据2002年4月至2003年1月在哑铃湾网箱养殖区水化学的现场调查,分析了网箱区和对照点底层海水中溶解无机氮磷的含量差异和季节变化特征,讨论了溶解态无机氮磷与环境因子的线性相关性,并对哑铃湾网箱养殖区底层海水的富营养化水平进行评价.结果表明:哑铃湾网箱养殖对底层海水pH值、DO、COD、NO-2-N 和NO-3-N的影响不明显,对NH 4-N、DIN和PO3-4-P的影响相对较大,短期养殖的影响较小,长期养殖的影响明显.溶解无机氮磷原子比值降低,使该海区营养盐结构的改变,对赤潮发生带来一定风险.季节上春、秋季的影响更明显.哑铃湾养殖区底层海水在春、秋两季已达到富营养化水平,养殖期越长,富营养化程度越高.  相似文献   

10.
2021年10月(秋季)对廉州湾近岸海域进行现场调查,分析廉州湾营养盐的分布特征,并利用富营养化指数和有机污染指数对该海域海水水质进行等级划分与评价。结果显示:秋季廉州湾海域的溶解态无机氮(DIN)浓度为0.149-1.587 mg/L,均值为0.493 mg/L;溶解态无机磷(DIP)浓度为0.010-0.084 mg/L,均值为0.033 mg/L;化学需氧量(COD)浓度为0.89-3.27 mg/L,均值为1.47 mg/L。DIN呈现近岸高、中部低的分布;DIP由湾内至湾外呈递减趋势,梯度分布明显,受河流输入影响显著。调查区域的富营养化指数为0.48-76.25,均值为12.23,大多数站位的水质状况属于轻度至中度富营养水平,严重富营养化主要出现在南流江口附近的站位;有机污染指数为-0.15-7.20,均值为1.80,研究区域50%的水质受到不同程度污染,南流江水质污染最严重,属于严重污染水域。总体来看,河流输入的陆源污染和人类对廉州湾海域的开发利用,是廉州湾海域富营养化和有机污染程度高的主要原因。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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