氮饥饿细基江蓠繁枝变型和孔石莼氨氮的吸收动力学特征

以氮饥饿海藻为材料,采用多瓶法和干扰法相结合的技术,测定两种海藻在不同起始浓度下不同时间间隔内的NH₄+吸收率,对不同阶段的吸收率进行非线性回归分析,结果表明它们均符合饱和吸收动力学特征.最大吸收率和半饱和常数均随着吸收时间的延长而降低.在整个吸收过程中,吸收曲线的初始斜率变化不大,这表明在低浓度下的吸收率不受短时间快吸收的影响而保持相对的稳定.同时两种海藻相比,在相应时间内的吸收动力学参数不同,孔石莼的最大吸收率、半饱和常数和初始斜率均大于细基江蓠繁枝变型.处于氮饥饿状态的两种海藻对NH₄+-N的吸收存在以下3个时相:(1)起始短期的快吸收阶段;(2)内部营养盐浓度控制的吸收阶段;(3)外界营养盐浓度控制的吸收阶段.     

温度、体重和摄食水平对花尾胡椒鲷幼鱼粪便比能值及吸收率的影响

鱼类没有消化的食物通过粪便而排出体外.没有消化的食物、黏液、消化道脱落细胞、代谢酶以及细菌等就组成了鱼类的粪便.排粪后所保留的食物能可以通过吸收率来估算,其计算式为:A=C-FC/C×100%,式中A(吸收率)以百分数表示;C(摄食量)等于摄入的食物质量乘以食物比能值;F(粪便排出量)等于排出的粪便质量乘以粪便比能值.吸收率在营养学上又称为消化率.粪便比能值的测定在计算吸收率时是非常必要的,但在以往对鱼类吸收率的研究[1～6]中,由于粪便收集的困难及粪便的样品量通常很少,均没有对不同条件下鱼类所排出粪便的比能值进行单独的测定.     

海水营养盐自动测定研究——Ⅲ.磷酸盐和硅酸盐的反流动注射分析

采用因子设计和单纯形优化对反流动注射分析测定海水中的PO₄3和SiO₃2进行了条件优化选择.设计的分析线路可以实现PO₄3、SiO₃2连续测定.样品测定速度为30个/h.PO₄3的测定存在明显的盐效应.SiO₃2的测定没有盐效应.彼此之间的干扰可以忽略.对实际样品测定并与规范法对比,二者结果基本一致.     

东海原甲藻吸收光谱特性分析

以东海原甲藻为研究对象,通过室内和室外的一系列培养实验.通过对不同生长时期其光吸收特性的变化和不同光强对其光吸收特性的影响进行研究,分析东海原甲藻先吸收特性研究及其爆发的可能机制.结果表明在培养的不同时期东海原甲藻光吸收特性差异明显,在不同光强条件下,当遮光率为77.7%时,最适于东海原甲藻生长.     

一种基于金属开口谐振环和杆阵列的左手材料宽带吸收器

用数值仿真在微波X波段研究了金属开口谐振环和杆阵列这一最基本的谐振结构.通过合理的参数调节,这种结构在10.91 GHz附近可以表现出高达98%的吸收率,并且半高峰宽达到3.5 GHz.用散射参量提取法计算其有效电磁参数,发现在谐振频率附近其介电常数、磁导率和折射率的实部均为负值.相比于传统的左手材料,这种结构的电磁参数在谐振区域均具有较大的虚部,是形成高吸收率的根本原因.本文的左手材料吸收器在电磁加热、电磁隐身等领域具有许多潜在的应用.     

原子吸收光谱仪用于沉积物中锡分析的方法研究

１９９４－１９９６年间,利用原子吸收光谱仪,对沉积物中有机锡和总锡的石墨炉原子吸收分析方法进行了优化,探讨了分析过程中的仪器条件和改进剂类型。优化后方法的检出限为 ２．４５μｇ／Ｌ（ＴＰＴ－锡）,特征浓度（相当于产生 １％净吸收或 ０．００４ ４吸光度的待测元素浓度）为４８２μｇ／Ｌ（ＴＰＴ－锡）。在这一条件下,采用盐酸酸化－正己烷萃取－氢氧化钠回洗－硝酸氧化的预处理方法,可以使沉积物样品中三苯基氯化锡（Ｔｒｉｐｈｅｎｙｌｔｉｎ, ＴＰＴ）的检出限达到４１ｎｇ／ｇ（ＴＰＴ－锡）,回收率为 １０６％。应用这一方法对野外模拟实验和黄岛电厂出水口的沉积物样品进行了分析,结果表明,这一方法能够满足对沉积物样品中锡进行分析的要求。     

光纤化学/生物传感技术在海洋环境监测中的应用

本文通过光纤溶解氧、 p H、湿度等化学传感探头及发光菌水质毒性监测生物传感探头的研制 ,开发出了一类能用于环境监测的新型传感器。本文的创新之处在于传感探头的设计与包装 ,以及数种可逆性、选择性、稳定性、使用寿命、响应时间、灵敏度等响应特性具佳的化学及生物传感膜的配方和制作技术。利用这些技术 ,通过对光纤探头的设计与包装 ,可以实现在现场及实验室模拟条件下对样品的选择性检测。研制的传感器能广泛应用于海洋污染调查、内河水质评价、水产养殖、工矿企业水气排污自检等诸多方面。     

海面环境下舰船目标的RCS测试建模分析

在分析国内外海面环境下舰船目标电磁散射特性测试建模技术研究现状和海面环境下舰船目标电磁散射特点的基础上,提出了一种"半确定性"的海面环境下舰船目标的电磁散射特性建模仿真计算方法.该方法可以在不具备外场全尺寸测试或造浪条件下电磁缩比试验条件时,以一定的置信度获取海面舰船的耦合电磁散射特性,为研究海面舰船雷达隐身设计验证提...     

一种胶体光子晶体修饰的光纤

设计了一种胶体光子晶体修饰的光纤. 采用恒温快速蒸发法直接在经切割刀处理后的光纤端面生长胶体晶体,再与另一根切割后的光纤在毛细玻璃管中完成对接,制备成胶体光子晶体修饰的光纤. 用扫描电子显微镜和光谱分析仪对样品的形貌、结构以及光学特性进行分析. 实验结果表明,粒径为640 nm、体积分数约为0.5%的SiO₂胶体微球溶液在60 ℃的情况下沉积,大约12 h后可得到质量较高的胶体光子晶体. 在SEM下,观察到端面的胶体晶体为面心立方(fcc)结构. 透射光谱证明,该结构在(111)面上     

深水滑翔机器人耐压壳体结构优化设计

针对深水滑翔机器人耐压壳体在深水中压缩变形和海水密度随水深增大而变化等因素造成驱动浮力变化问题,利用压缩变形和密度变化对驱动浮力影响的互补特性,归纳了载体耐压壳体结构优化设计方法.保证耐压壳体抗压条件和质量最小前提下采用结构优化设计方法,降低耐压壳体压缩变形和海水密度变化对驱动浮力的影响,提高系统能源的利用率.     

中国拟鸡冠菜属的一个新种

对1958年4月采自西沙群岛永兴岛的红翎菜科麒麟菜族标本AST 58-4195号、AST 58—4154A号和AST 58-4158号进行切片与染色的分类研究。将其与该科中相近的麒麟菜属、琼枝藻属和卡帕藻属的不同种一起，进行了营养体的外部形态和内部构造，尤其是囊果的形态与切面特征的详细比较、研究和鉴定。结果表明，这些标本是我国目前尚未报道的红翎菜科拟鸡冠菜属的一个新种：具花拟鸡冠菜Meristiella florigia sp．nov．。     

日本新糠虾消化系统组织学研究

对日本新糠虾消化系统进行了组织学观察。日本新糠虾消化道可分为三大部分：前肠、中肠和后肠,组织结构由内向外均分为粘膜层、粘膜下层、肌层和外膜4层。其中,前肠由口、食道、胃等组成;中肠有中肠前盲囊和中肠腺等附属结构。中肠腺腺管上皮细胞由4种类型细胞组成,分别称为胚细胞（E细胞）、纤维细胞（F细胞）、吸收细胞（R细胞）和泡状细胞（B细胞）。     

基于图像分层搜索的地形轮廓匹配算法设计

应用图像分层搜索序贯判决算法,进行海底地形轮廓匹配（TERCOM）算法设计。建立了上下两层同时匹配的比较控制逻辑,既提高了匹配速度,又减少了误匹配,增强了地形二维匹配的健壮性。应用实际海图原始数据进行仿真。结果表明,该算法在保持匹配速度的同时具有较高的匹配精度和抗差特性。     

Hydrothermal mineralization along submarine rift zones,Hawaii

This is the first article to describe mineralization of midplate submarine rift zones and hydrothermal manganese oxide mineralization of midplate volcanic edifices. Hydrothermal Mn oxides were recovered from submarine extensions of two Hawaiian rift zones, along Haleakala and Puna Ridges. These Mn oxides form two types of deposits, metallic stratiform layers in volcaniclastic rocks and cement for clastic rocks; both deposit types are composed of todorokite and bimessite. Thin Fe‐Mn crusts that coat some rocks formed by a combination of hydrogenetic and hydrothermal processes and are composed of δ‐MnO₂. The stratiform layers have high Mn contents (mean 40%) and a large fractionation between Mn and Fe (Fe/Mn = 0.04). Unlike most other hydrothermal Mn oxide deposits, those from Hawaiian rift zones are enriched in the trace metals Zn, Co, Ba, Mo, Sr, V, and especially Ni (mean 0.16%). Metals are derived from three sources: mafic and ultramafic rocks leached by circulating hydrothermal fluids, clastic material (in Mn‐cemented sandstone), and seawater that mixed with the hydrothermal fluids. Mineralization on Haleakala Ridge occurred sometime during the past 200 to 400 ka, when the summit was at a water depth of more than 1,000 m. Hydrothermal circulation was probably driven by heat produced by intrusion of dikces, magma reservoirs, and flow of magma through axial and lateral conduits. The supply of seawater to ridge interiors must be extensive because of their high porosity and permeability. Precipitation of Mn oxide below the seafloor is indicated by its occurrence as cement, growth textures that show mineralizing fluids were introduced from below, and pervasive replacement of original matrix of clastic rocks.     

Full waveform inversion of field sonar returns for a visco-acousticEarth; a comparison of linearized and fully nonlinear methods

The techniques of linearized least squares inversion (LLSI) and simulated annealing (SA) are both used to invert a series of synthetic and real normal-incidence, geo-acoustic sonar returns for estimates of impedance versus two-way travel time in the top several meters of ocean floor sediment. The objective is to determine the better (faster, more accurate) method for inverting this class of data. LLSI uses an over parameterized earth, i.e., one composed of layers whose thickness corresponds to a travel time equal to the sample interval. This makes the inverse problem quite large, but also makes it nearly linear. SA uses a more efficient parameterization, one whose layers have variable thickness as well as variable impedance. Because of the relatively narrow frequency band (~1 octave at 20 dB down from the peak) the time domain signal is oscillatory and inversion for layer thickness is nonlinear. Results show greater time efficiency in solving the large linear problem (LLSI) than in solving the small nonlinear problem (SA). However, in both cases almost all of the waveform energy was modeled, indicating that essentially all the information in the data had been successfully recovered. The inversions are applied to 10-20 kHz field data acquired offshore Florida, and several techniques are employed to enhance the effectiveness of each inversion method     

海南新纪录种东方蜈蚣藻(红藻门)的形态学观察和rbcL 基因序列分析

通过形态结构观察、生殖器官的发育和rbcL序列分析相结合的方法,发现了分布于海南省陵水新村的东方蜈蚣藻(Grateloupia orientalis S.-M.Lin et H.-Y.Liang)为海南新纪录种,该物种具有以下特征:藻体质地凝胶状或软骨质;皮层外部由5～6层念珠状的细胞构成,内部由1～2层星形细胞构成;生殖枝丛由两个分枝组成;果孢子囊分布在除藻体基部外的皮层内.     

泥螺生殖系统的组织学研究

随机选取不同发育阶段的泥螺 ,活体解剖 ,取出其生殖系统 ,切成若干小段 ,按常规组织学方法制成切片 ,光学显微镜观察并拍照 ,对其生殖系统的组织学进行研究。结果表明 ,泥螺生殖系统由生殖器本部 ,交媾器和卵精沟三部分组成。生殖器本部包括两性腺、两性管、精囊、蛋白腺、粘液腺、缠卵腺、交媾囊、摄护腺。卵巢位于两性腺周围 ,精巢位于中间 ,并先熟先形成精子。生殖细胞成熟后经由单层上皮细胞组织的两性管排出 ,两性管末端的交媾囊为精卵受精的部位。交媾囊一侧的蛋白腺、粘液腺分别分泌蛋白质及粘液包围卵。交媾器包括刺激器与阴茎两部分 ,两者均由多层肌肉细胞组成。外卵精沟由皮肤凹陷而成 ,沟壁具纤毛。     

Vertical impedance of tapered piles considering the vertical reaction of surrounding soil and construction disturbance

The pile–soil system is divided into layers of sufficient number such that the shear stiffness at the pile–soil interface can be determined based on the complex stiffness transfer method. The vertical reaction of surrounding soil on the annular projections at the interface of adjacent pile segments is simplified using Voigt model, whose spring and damping coefficients are derived afterward, allowing an amended impedance function transfer method to be proposed. Using the amended impedance function transfer method, the dynamic equilibrium equation of the pile is solved to give an analytical solution for the impedance function at the pile top. By comparing the solution proposed in this paper with other solutions, the superiority of the bearing capacity of a tapered pile is further confirmed. A parameter study is then conducted to give insight into the coupled interaction of the vertical reaction of the surrounding soil with construction disturbance in the low-frequency range concerned in the seismic design of the pile foundations.     

Axisymmetric viscoelastic response of flexible pipes in time domain

The challenges for determining the mechanical behavior of flexible pipes mainly arise from highly non-linear geometrical and material properties and complex contact interaction conditions between and within layers components. This paper develops an innovative model to investigate the linear viscoelastic behavior of flexible pipes under axisymmetric loads in time domain. The model is derived from an equivalent linear elastic axisymmetric model by invoking the elastic-viscoelastic correspondence principle. Analytical formulations that describe the behavior of the metallic helical layers based on a combination of differential geometry concepts and Clebsch–Kirchhoff equilibrium equations for initially curved slender elastic rods are presented. The elastic response of the homogenous polymeric cylindrical layers is also presented. The assemblage of both types of governing algebraic equations that approximate analytical solutions for force and moment distributions, deformations in each layer, as well as contact pressure between near layers, taking time-dependent characteristics of polymeric layers into account are provided and it is clear that the relationship between axial force and elongation is non-linear and encompasses a hysteretic response. Besides, the creep behavior in axial direction can also be found. Some insights into the differences in the behavior for several loading conditions are discussed by considering variable frequencies.