Holocene permafrost history and cryostratigraphy in the High‐Arctic Adventdalen Valley,central Svalbard

This paper presents the history and cryostratigraphy of the upper permafrost in the High‐Arctic Adventdalen Valley, central Svalbard. Nineteen frozen sediment cores, up to 10.7 m long, obtained at five periglacial landforms, were analysed for cryostructures, ice, carbon and solute contents, and grain‐size distribution, and were ¹⁴C‐ and OSL‐dated. Spatial variability in ice and carbon contents is closely related to the sedimentary history and mode of permafrost aggradation. In the valley bottom, saline epigenetic permafrost with pore ice down to depths of 10.7 m depth formed in deltaic sediments since the mid‐Holocene; cryopegs were encountered below 6 m. In the top 1 to 5 m, syngenetic and quasi‐syngenetic permafrost with microlenticular, lenticular, suspended and organic‐matrix cryostructures developed due to loess and alluvial sedimentation since the colder late Holocene, which resulted in the burial of organic material. At the transition between deltaic sediments and loess, massive ice bodies occurred. A pingo developed where the deltaic sediments reached the surface. On hillslopes, suspended cryostructure on solifluction sheets indicates quasi‐syngenetic permafrost aggradation; lobes, in contrast, were ice‐poor. Suspended cryostructure in eluvial deposits reflects epigenetic or quasi‐syngenetic permafrost formation on a weathered bedrock plateau. Landform‐scale spatial variations in ground ice and carbon relate to variations in slope, sedimentation rate, moisture conditions and stratigraphy. Although the study reveals close links between Holocene landscape evolution and permafrost history, our results emphasize a large uncertainty in using terrain surface indicators to infer ground‐ice contents and upscale from core to landform scale in mountainous permafrost landscapes.     

FEASIBLE STUDY ON THE INTEGRATION SYSTEM FOR THE SPACE MONITORING OF MAJOR EARTHQUAKES AND VOLCANOES IN TERRESTRIAL LAND

With the rapid development of space technology, earth observation technology and sky observatory technolo-gy, they have played a more and more important part in monitoring and predicting of earthquakes and volcanoes in the terres-trial land. In recent years, the related agencies have done the experiments and researches on monitoring and predicting ofearthquakes and volcanoes in the forewarning period by means of many approaches, such as satellite thermal infrared re-mote sensing (TIRS), Global Positioning System (GPS), differential interferometric synthesis aperture radar (D-INSAR),astronomical time-latitude residual anomaly, and Geographic Information Systems (GIS), etc. A quite large number of re-search foundation has been built in the fundamental theories and application methods. The experiments and researcheshave shown that these technology is efficient methods for high frequency crust movement. If the existed separate scientificforces and results are possibly assembled together to form a more complete integration monitoring system with the combina-tion of space, sky observation, ground, deep geology and macro anomaly, it will come into a new stage of monitoring andpredicting of earthquakes and volcanic eruptions.     

The brine shrimp (Artemia parthenogenetica) as encapsulation organism for prophylactic chemotherapy of fish and prawn

Brine shrimp (Artemia parthenogenetica) which had ingested three water-insoluble antibacterial drugs i.e. sulfadiazine(SD), oxytetracycline (OTC) and erythromycin estolate (ERY-Es) were fed toTilapia and Mysis IIIof Penaeus orientalis K. The drug contents in the predators were then determined. After administration of drugs toTilapia and Mysis III, through the bio-encapsulation of the brine shrimp, efficacious therapeutical concentration of OTC and ERY-Es (but not SD) in the predators could be reached and maintained for more than 8 hours.     

星风吸积引起的钡星重元素超丰

首先指出目前星风吸积模型中理论上的不自洽，考虑到δｒ≠０，重新推导轨道参量变化方程，消去了理论上的不自洽．提出一个新模型：首次将星风吸积同内禀ＡＧＢ星核合成模型结合起来计算钡（Ｂａ）星的重元素超丰，并将计算结果与观测值进行了比较．各参量按标准情况取值时，计算结果不太理想．取Ｂｏｎｄｉｈｏｙｌｅ吸积率的０．５倍或取较大的星风速率时，对于较长轨道周期（Ｐ＞１０００天）的Ｂａ星，计算结果与观测值基本符合；而较短轨道周期（Ｐ＜６００天）的Ｂａ星，其重元素超丰机制可能是盘吸积     

STRESS CORROSION CRACKING OF AISI 321 STAINLESS STEEL IN ACIDIC SEAWATER

ImooUonONSCCisoneofthemosttwortantcausoffailureofstaiuleSsstalequipmentandfacilitieS.Studiesonunh0refacilitiesshowedthatanaddicchloridesolutionfilmcouldbefo~onthescheeofstalandthatstaiuleSSstalisinaCtivedissolutionstateinaedicchloridesolutionopinetal.,l99O;Gnanamoorthyetal.,l99O).ltisgenerallythoughtxthatSCCcannotoimrwhenthematerialisinaCtiveanodicdissolutionstate,soitsomcewithresultingcasualties(0ldfieldetal.,l99O)arousedattentiont0it.SomeSCCmeCanisrnsproposedpeuang,l988,Newmanctal.,…     

Protective effect of topically applied polypeptide from Chlamys farreri against ultraviolet radiation-induced chronic skin damage in guinea pig

Polypeptide fromChlamys farreri (PCF), a topical polypeptide isolated fromChlamys farreri, was used in this experiment aimed to investigate the photoprotective effect of PCF against chronic skin damage induced by ultraviolet A (UVA) and ultraviolet B (UVB) radiation. The chronic ultraviolet-irradiated guinea pig model was established, and visible changes in the skin including wrinkling, sagging and erythema were observed. Malondialdehyde (MDA) and antioxidant enzymes including superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) in the dorsal skin were determined using biochemical methods. The results showed: (1) PCF (5 % and 20%) could greatly protect the dorsal skin of guinea pig against wrinkling, sagging and erythema induced by UV radiation in a concentration-dependent manner. (2) PCF could reduce MDA formation in the dorsal skin caused by UV irradiation, while increasing the activities of SOD and GSH-px. (3) The differences among the PCF groups and UV model group were significant (P<0.05,P<0.01). These results indicated that topical application, of PCF provided broad solar UV spectrum photoprotection; and that the antioxidant property of PCF might play a role in photoprotection. Project No. 39970638 supported by the NSFC, and the Science and Technology Bureau of Qingdao (No. 2001-28-50).     

测定天琴RR变星金属丰度的方法

银晕中天琴RR变星金属丰度的测定对于研究银河系晕的形成和演化具有重要的意义．在当前的技术条件下,高分辨光谱的方法难以测量银晕中较暗的天琴RR变星的金属丰度．高分辨光谱测定金属丰度的方法对恒星大气模型的依赖性较高,而恒星脉动引起的复杂大气状况对于建立正确的大气模型本身就是挑战．△S光谱方法、Caby测光方法和光变曲线的参数方法则弥补了高分辨光谱方法的不足,将能测量更远距离上的天琴RR变星的金属丰度．着重介绍了这3种方法发展的历史、具体的观测流程以及需要注意的问题。通过比较这3种方法的优劣,为实际观测时方法的选用提供借鉴。     

Application of Grain Size Analysis to Study Sedimentary Environment of Sand Dune in the Vicinity of Tumen River

The dunes in estuary of Tumen River in China lie to the area between the Jiushaping and Fangchuan in the left bank of Tumen River (Fig.1). The dis-tance is about 15～20 km between the dunes and the coast. It ranges from China to D. P. R. Korea and Russia. The range of the height of dunes is about 15～20 m and the width is 100～200 m. By the re-connaissance, we protracted 9 section planes of the dunes and collected 40 sand samples of the dunes, and identified the sedimentary environment …     

类太阳色球活动星εEri磁场的观测研究

本文给出１９９３—１９９４年期间，用云南天文台１米望远镜折轴摄谱仪观测获得类太阳色球活动星。εＥｒｉ的５个波段高分辨、高信噪比光谱，运用两种不同方法：谱线轮廓塞曼致宽分析和多重线统计分析法成功地测定了εＥｒｉ的表面磁场强度和磁场的覆盖因子，并对这两种磁场测定方法作了简单的讨论．