中国对虾(Penaeus chinensis)四倍体诱导研究

利用光控和行为学原理,控制中国对虾在适当时候产卵,在一定的时刻以温度休克和细胞松弛素的方法诱导受精卵发育成为四倍体。作者发展了对虾染色体制备技术,以中肠和触角腺、精巢为材料,从后期幼体直到8～9cm左右次成虾均获得较好的分裂中相。染色体倍性检测结果表明,最好的四倍体诱导成功率达66.7％。共获得10cm左右的实验对虾几千尾。初步观察表明,四倍体中国对虾具有一定的生长优势。     

一个南海热带气旋发展的环流特征分析

本文用ECMWF2.5×2.5网格点资料通过一个例子,对有利于南海热带气旋发展的环流场作了详细的分析,发现几点事实:(1)扰动在风的垂直切变较大的环境中仍可发展。(2)扰动位于中、低空西南急流左侧,高空南支东风急流右侧时,有利发展。(3)中,低空西南急流形成了扰动环流的强风潮,强风潮从扰动南侧入角,并包围扰动的东半圆。(4)扰动中、低层的入流和高层的外流呈现严重的不对称性。(5)当扰动发展到一定强度时,对南海热带季风环流圈的加强起到正反馈作用。     

济州岛附近海域表层沉积物中的颗石及其古海洋学

对济州岛附近海域表层沉积物中的颗石进行研究,共发现40个种。根据对颗石进行多元统计分析的结果,可将本区划为两个环境区、两个颗石组合。提出海流是控制本区颗石分布的主要因素。     

海藻硫酸多糖911对小鼠脾淋巴细胞增殖反应及对细胞产生IL—2作用的影响

本文以~3H—TdR掺入法观察911对小鼠脾淋巴细胞增殖反应的影响并用CTLL细胞检测了其对IL—2的作用。体外实验结果表明,911对小鼠脾淋巴细胞增殖反应有明显的增强作用,以0.5μg/ml的浓度效果最为明显,相对增殖指数RPI可达200％;体内实验则以5mg/kg体重ip,连续7d效果最好,相对增殖指数RPI可达176％;911用药组小鼠IL—2的产生量均高于对照组,以5mg/kg和10mg/kg效果最好。以上实验证明,这一多糖是一种有希望的新免疫调节药物。     

黄海陆架表层水温的低频振动

本文在对位于黄海南部陆架上的朝连岛站30年水温资料进行分析时发现,该站的表层水温有周期大于20个月的低频振动,其中以准两年周期和6年周期最显著。陆架水温的这种低频振动是对东亚季风异常的响应。这种低频振动在冬季与渤海冰情的变化同步;在夏季与黄海底层冷水团的强弱相关。同时,这种低频振动在对马暖流上也有一定的反映。     

Sediment–water interactions of natural oestrogens under estuarine conditions

The natural human female hormones oestrone and 17β-oestradiol have been implicated in the disruption of endocrine systems in some wildlife adjacent to sewage effluents. The sorption behaviour of these two compounds under estuarine conditions was studied by spiking either 2.55 μg of oestrone or 2.65 μg of 17β-oestradiol in kinetic experiments. In equilibrium experiments, 3 ng of oestrone or 3.2 ng of 17β-oestradiol was added in each of the centrifuge tubes. Sorption onto sediment particles was relatively slow, with sorption equilibrium being reached in about 70 and 170 h for oestrone and 17β-oestradiol, respectively. The effects of a variety of environmental parameters on sorption were studied including salinity, sediment concentration (SC), the presence of a third phase, particle size and, also, surfactant concentrations. Results show that although salinity did not induce any statistically significant effect on the sorption of 17β-oestradiol, it did statistically enhance the sorption of oestrone, and a salting constant of 0.3 l mol⁻¹ was derived. The partition coefficient for both compounds decreased with increasing sediment concentration, a phenomenon that has been widely reported and attributed to the presence of colloids (which could enhance dissolved concentrations). In this paper, the true partition coefficients for sediment particles (K_p^true) and colloidal particles (K_c^true) have been calculated, and a K_p^true value of 141 and 102 ml g⁻¹ was obtained for oestrone and 17β-oestradiol, respectively. In addition, K_c^true values for oestrone (222×10² ml g⁻¹) and 17β-oestradiol (135×10² ml g⁻¹) were two orders of magnitude higher than their respective K_p^true values, suggesting that the colloidal particles are significantly stronger sorbents for natural oestrogens than sediment particles. Particles of different sizes were found to have different partition coefficients due to the strong relationships between partition coefficients for the two compounds and particulate organic carbon (POC) contents and specific surface areas (SSAs). The presence of a surfactant was shown to reduce the partition coefficients for the two compounds, although its concentrations being used were higher than those normally found in the natural environment.     

光照强度对海洋微藻脂肪含量及脂肪酸组成影响的研究

近年来，海洋微藻脂肪酸组成的研究及其应用越来越受到国内外科学家的重视。高度不饱和脂肪酸(PUFA)，特别是长链的n-3 PUFA，如二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)对海洋动物和人类都具有营养学和医学上的价值。在海洋微藻的培养过程中，光照强度是海洋微藻生长的条件之一，光线的明与暗，光度的强与弱，不仅对微藻的生长速率、产量有影响，而且对其脂肪含量和脂肪酸的组成也有影响(Teshima et al.，1983；Thompson et al.，1990； Renaud et al., 1991)。 作者在以往研究的基础上，选择了3种有代表性的海洋微藻：(1)小球藻Chlorella sp-2(李荷芳等，1999)，此藻脂肪酸中EPA含量高、且不含DHA；(2)球等鞭金藻(Isochrysis galbana)，该藻DHA含量较高，但几乎不含EPA；(3)前沟藻(Amphidinium sp.)的EPA、DHA含量均高。将以上3种微藻作为原料，在不同的光照强度下进行培养，测定并分析藻体中的脂肪含量和脂肪酸组成的变化，从而了解光强对海洋微藻脂肪含量及其脂肪酸组成的影响。     

Analysis of radial movement of an unconfined leaky aquifer due to well pumping and injection

Radial movement of an unconfined leaky aquifer was studied with respect to hydraulic forces that are induced by well recharge and discharge. New analytic solutions in the velocity and displacement fields were found and applied to describe transient movement in an unconfined leaky aquifer. Linear momentum and mass balance of saturated porous sediments, the Darcy-Gersevanov law, and the analytic solution of hydraulic drawdown for unsteady flow within the unconfined leaky aquifer were introduced to find the new solutions. Analytic results indicate that the nonlinear relation between the initial hydraulic head (h₀) and the well function has an insignificant effect on the aquifer transient movement when the drawdown s<0.02h ₀. When the well function is simplified with different assumptions and pumping conditions, the new solutions correspondingly reduce to cases that are similar to the Hantush-Jacob, Muskat, and Theis transient movement of a confined leaky aquifer. It was found that large leakance is important in slowing radial movement and reducing aquifer deformation. Flow velocity in the aquifer is more responsive to leakance than to cumulative displacement within the aquifer. The zones and boundary with tensile stress can be located using the same approach applied to a confined aquifer for risk assessment of earth fissuring.

---

Résumé Le mouvement radial dans un aquifère semi-perméable libre a été étudié en considérant les forces hydrauliques induites par la recharge et le prélèvement au niveau d’un puits. De nouvelles solutions analytiques des champs de vitesse et de déplacement ont été trouvées et appliquées pour décrire le mouvement transitoire dans un aquifère semi-perméable libre. Pour trouver les nouvelles solutions, le moment linéaire et le bilan de masse dans les sédiments poreux saturés, la loi de Darcy-Gersevanov, et la solution analytique du rabattement hydraulique pour un écoulement transitoire dans un aquifère semi-perméable libre sont pris en compte. Les résultats analytiques montrent que la relation non-linéaire entre le potentiel hydraulique initial (h₀) et la fonction de puits a un effet insignifiant sur le mouvement transitoire de l’aquifère quand le rabattements s <0.02h₀. Si la fonction de puits est simplifiée en tenant compte de différentes hypothèses et conditions de pompage, les nouvelles solutions se réduisent en conséquence à des cas similaires au mouvement transitoire dans un aquifère semi-perméable captif selon Hantush-Jacob, Muskat, et Theis. Il s’est avéré qu’une drainance élevée est importante pour le ralentissement du mouvement radial et la réduction de la déformation de l’aquifère. La vitesse d’écoulement dans l’aquifère est plus sensible à la drainance qu’au déplacement cumulé dans l’aquifère. Les zones et la frontière présentant des contraintes de traction peuvent être localisées en utilisant la même approche appliquée à un aquifère captif pour l’évaluation des risques de fissuration du sol.

---

Resumen Se ha estudiado el movimiento radial en un acuífero no confinado con fuga en relación a las fuerzas hidráulicas que son inducidas por la descarga y recarga del pozo. Se encontraron nuevas soluciones analíticas en los campos de desplazamiento y velocidad, las cuales se aplicaron para describir el movimiento transitorio en un acuífero no confinado con fuga. Se han introducido cálculos de balance de masa y momentum lineal de los sedimentos porosos saturados, la Ley Darcy-Gersevanov, y la solución analítica de descenso hidráulico para flujo sin régimen permanente dentro del acuífero no confinado con goteo para encontrar las nuevas soluciones. Los resultados analíticos indican que la relación no lineal entre la presión hidráulica inicial (h₀) y la función del pozo tiene efecto insignificante en el movimiento transitorio del acuífero cuando el descenso s < 0.02h₀. Cuando se simplifica la función del pozo en base a diferentes supuestos y condiciones de bombeo se reducen las nuevas soluciones a casos que son similares a el movimiento transitorio Hantush-Jacob, Muskat, y Theis de un acuífero confinado con goteo. Se encontró que las fugas grandes son importantes en la disminución del movimiento radial y en la reducción de la deformación del acuífero. La velocidad de flujo en el acuífero responde más a las fugas que al desplazamiento acumulativo dentro del acuífero. Pueden localizarse zonas y límites con esfuerzos tensionales usando el mismo enfoque aplicado a acuíferos confinados para evaluación de riesgo de generación de fracturas en el terreno.

---

     

In situ investigation into fracture and subsidence of overburden strata for solid backfill mining

Controlling the subsidence of overburden strata is the main objective for backfill mining technology. In order to understand the controlling effect of filling body, a detection scheme with three direction boreholes was designed in the tailgate of T₃290 mining face in Tangshan Coal Mine to monitor the fracture developing process of overburden strata. In addition, a few displacement and stress sensors used for monitoring the roof subsidence and filling body stress were arranged behind the longwall face to monitor and record the force and deformation of gangue. The field investigation shows that the solid backfill mining technology can effectively reduce the fracture of overburden strata, i.e., the fracture height and the damage degree. The subsidence of overburden strata is mainly caused by the subsidence of roof which is divided into four stages: roof subsidence stage of mining face, rapid subsidence stage of gob roof, relatively stable stage, and long-term rheological stage. The gauge plays an essential role in slowing down the subsidence in each stage of the overburden subsidence, especially the relatively stable stage.     

Time and frequency domains response analyses of April 2015 Greece’s earthquake in the Nile Delta based on GNSS-PPP

Earthquake response characteristic and sensitivity of 1-Hz Global Navigation Satellite System - precise point positioning (GNSS-PPP) for a seismic response in time and frequency domains are the main objectives of this study. The Delta and Cairo areas, Egypt, experiencing the shock of the Greece earthquake occurring on April 16, 2015 (18:50 hours), is presented in this study. The results of this study reveal that the seismic wave effect is very small and can be neglected inside the Delta region and the strong motion occurred in an upward direction for the whole monitoring area. Furthermore, the time-frequency analysis illustrates the ability of the time and frequency domains to use and analyze the surface motion based on a 1-Hz sampling frequency and to detect the small- and high-strength motions of seismic waves.