不同模式对虾养殖水体中硝酸盐和亚硝酸盐的变化特征及其影响因素

于2001年10月15～19日在广西海洋研究所曲湾养殖基地,选择养殖南美白对虾(Penaeus vannamei)的8个封闭式的工厂化养殖池和4个开放式的水泥底普通养殖池,连续5d取样分析不同模式、不同密度、不同面积养殖水体中硝酸盐和亚硝酸盐的变化及其与环境因子之间的关系。结果表明,工厂化养殖水体中,硝酸盐和亚硝酸盐含量显著偏高,平均值分别为11．31mg／L和4．70mg／L;硝酸盐和亚硝酸盐含量随时间增加而升高,随养殖面积增大而下降。普通养殖水体中,硝酸盐和亚硝酸盐含量显著偏低,平均值分别为0．017mg／L和0．060mg／L,硝酸盐和亚硝酸盐含量在时间变化上无明显规律性。养殖水体中硝酸盐和亚硝酸盐含量与COD呈显著的正相关,与叶绿素a含量呈显著负相关关系,突出体现化学作用的输入影响及生物吸收的输出影响。     

台风对封闭式工厂化虾池生态系统中水环境因子的影响

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.     

关于指数丢番图方程x2+by=cz

设m是偶数，r是奇数；又设Ur、Vr是适合Vr＋Ur√-1=（m＋√-1）^r的整数．笔者证明了：当a=｜Vr｜，b=｜Ur｜，c=m^2＋1，r=3（mod4），m〉r／π且m是2的方幂时，指数丢番图方程仅有正整数解．     

大规格凡纳滨对虾健康养殖试验

为寻找出一条适合广西北海地区高产、稳产、高效益、可持续发展的大规格对虾养殖模式,通过凡纳滨对虾（Litopenaeus vanmamei）无公害健康养殖试验,获得了显著效果。养殖池1口,面积0．2hm^2,放养虾苗的体长0．8～1．0cm,共8万尾。经136d养殖,获对虾1403．7kg,平均7018．5kg／hm^2,规格37．4尾／kg,成活率65．6％。产值44918元,扣除生产成本25854元,获利19064元,平均每公顷获利95322元。     

凡纳滨对虾养殖早期水体中氮磷营养盐变化规律研究

为探讨凡纳滨对虾养殖早期水体中主要营养盐含量及其变化,测定了对虾池水体中的氨氮、硝酸盐、亚硝酸和磷酸盐。结果显示,氨氮浓度变化范围：0．3-0．02mg／L,硝酸盐浓度变化范围：0．29-8．68mg／L,亚硝酸盐浓度变化范围：0．15-8．50mg/L,磷酸盐浓度变化范围：004-1．10mg／L。在养殖早期水体中,氨氮浓度呈波动变化,硝酸盐、亚硝酸盐和磷酸盐含量相对稳定。     

标准型绝对值函数的分段函数形式及应用

获得了化标准型函数 y=｜｜x｜-a｜=y=｜…｜｜x｜-a｜…-a｜（a〉0,n∈N）分段函数的一般解析式，举例说明了化标准型绝对值函数为分段函数形式的数学应用。     

乌龙茶覆盖遮荫技术的研究

进行了夏季乌龙茶园不同遮荫度遮荫的生态生理生化效应及其对茶树生长、产量和品质的影响研究．结果表明：与不遮荫的对照处理相比，遮荫后，(1)树冠层的白昼平均温度、日极端最高温度和温度日较差分别下降了1．47～4．29℃、3．95～7．26℃和3．33～8．44℃；白昼平均相对湿度、日极端最低相对湿度分别增加了4．31％～12．31％和3．27％～12．62％，相对湿度日较差减少了3．58％～12．94％．(2)夏、暑梢1芽3叶含水率分别增加了4．57％～6．47％和2．24％～2．78％．(3)夏、暑梢叶绿素总量分别增加了0．5983～0．7019mg／dm^2和0．3480～0．6050mg／dm^2．增幅达41．70%～48．92％和52．38％～91．06％；叶绿素a增加38．96％～47．25％和50．94％～72．52％；叶绿素b增加了43．83％～54．58％和67．98％～155．81％；叶绿素a、b比值下降了0．1042～0．1868和1．10～3．54．(4)茶叶中茶多酚和咖啡碱含量明显降低，氨基酸含量明显提高，粗纤维含量显减少．儿茶素组份得以优化．(5)适度遮荫有利于提高夏暑茶的产量和品质．     

带有临界Sobolev和Hardy项的半线性椭圆方程的解（I）

设Ω包含R^N是有界光滑区域，0 ∈Ω ,N≥3,2^＊：=2N/N-2,0≤s〈2,2^＊（s）：=2（N-s）/N-2,2〈r〈2^＊（s）．对于满足一定条件的参数λ和μ，证明了带Diriehlet边界条件的奇异椭圆问题-△u-μu/｜x｜^2=｜u｜^2＋-2u＋λ｜u｜^r-2/｜x｜^1u的一些重要性质．     

一类带有Hardy项和Sobolev—Hardy临界指数椭圆方程的非平凡解

研究了一类带有Hardy项和Sobolev—Hardy临界指数的椭圆方程{-△u-u＋h（x）/｜x｜2u=｜u｜2·（s）-2/｜x｜s u＋λ｜u｜q-2 u,x∈Ω; u=0,x∈ Ω。通过运用变分方法和精确估计得到了非平凡解u∈D 1,2（Ω）的存在性．其中：Ω R N（N≥3）是一个有界光滑区域,0∈Ω,λ〉0,u∈R,0≤s〈2．     

一类p-Laplace发展方程解的存在性

研究了一类p—Laplace发展方程ut=div（｜▽u｜^p-2▽u）＋au∫Ωu^q（x,t）dx在一个有界域Ω R^N（N〉2）解的存在性,其中Δp=div（｜▽u｜^p-2▽u）,P〉1,r,q〉0．证明了当r,q≥1时,方程的解唯一存在;而在r〈1或者q〈1时局部解存在,但唯一性未必成立．     

Markedness and its Interpretation in Language Use

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Design and analysis of generic LBS application developing platform

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

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.     

On Tragic Consciousness In The Works By Ernest Hemingway

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.