THE HISTORICAL CLIMATIC RECORDS IN ICE CORES FROM THE SURFACE LAYER OF WILKES LAND, ANTARCTICA

The information preserved in the surface layer of the Antarctic ice sheet is so abundant and detailed that in the areas with a high accumulation rate the annual climatic changes in the past can be distinguished. After conducting an investigation into the stratigraphical features of ice cores from two typical shallow boreholes in the Wilkes Land, one inland and another near the margin, analyzing δ(~18)O and the gross β radioactivity in the cores, as well as anslyzing the power spectra of δ~(18)O, the authors present some important assessments on the climatic information in the past several decades therein such as the annual mean temperature and precipitation, and suggest that there is a period of 11 years with which the climate changes cyclically in East Antactica. Such a studying method will be of value in both theory and practice to the inland Antarctica, where direct meteorological observation is deficient.     

THE COMPARISON OF LANZHOU LOESS PROFILE WITH VOSTOK ICE CORE IN ANTARCTICA OVER THE LAST GLACIATION CYCLE

Loess near Lanzhou in the late Pleistocene is very sensitive to climatic fluctuations. The Beiyuan terrace profile in Linxia City, of which the curve of susceptibility tallies with the trend of isotopic curves of Vostok 2083 m ice core in Antarctica, is 35m thick. There are five layers of paleosols under Malan loess(L_1). Upper three layers (S_(1-a),S(1-b)and S_(1-c) correspond to three warm stages in last interglaciation, Interstadial of Last Glacial (C stage in Antarctic ice core)was clearly recorded in the Beiyuan profile, in which three layers of paleosols and two of loess were formed. The lowest section of the profile belongs to penultimate glaciation, in which fossils of cold-drought-resistant mammal and mollusc have been discovered.     

AN ENORMOUS THRUST NAPPE AND EXTENSIONAL METAMORPHIC CORE COMPLEX NEWLY DISCOVERED IN SINO-MONGOLIAN BOUNDARY AREA

An enormous thrust nappe and a metamorphic core complex of extensional origin have been recently discovered within the Hercynian-Indosinian orogen of Inner Mongolia. Both features are of the Mesozoic age, but the former is older. The thrust nappe strikes WNW-ESE and Proterozoic dolomite was thrust southwards atop strata ranging from the Cambrian to the Triassic in age. The visible displacement of the thrust is ca. 70 km and the deduced one is over 140 km. The metamorphic core complex (mainly mylonites) extends in an N-E direction, forming itself into a dome geometry and lying under an extensional detachment fault. The mylonitic foliation dips gently and the stretching mineral lineation, as a whole, plunges SSE. Various shear sense markers show a normal-sense shear movement. Some significant problems atise from the coexistence of nappe and extensional structures at a postoro-genic stage.     

钢铁及其合金中铬含量测定结果的不确定度评定

对用GB／T223、11—1991《过硫酸铵氧化容量法测定铬量》的方法测定钢铁及合金中铬含量测量结果的不确定度进行了评定。对样品测量过程中的不确定度分量进行了分析和量化,求得铬含量测定结果的标准不确定度和扩展不确定度分别为0．06％和0．12％。     

J-聚集体生成中阴离子菁与外加盐反离子相互作用的量热与电化学活度测量

用量热和反离子活度测量法研究了阴离子菁(Ⅰ)在DMF-水(35%DMF,V/V)中生成J-聚集体时,染料与外加盐反离子之间的相互作用。当外加盐为CdCl_2或LaCl_3时,由量热曲线获得J-聚集焓△H_9,分别为-42.6,-42.0kJ·mol~(-1),染料(Ⅰ)束缚的Cd~(2 ),La~(3 )量与染料量之比分别为0.48:1和0.31:1。由反离子活度的电化学活度测量获得束缚的Cd~(2 )离子量与染料量之比为0.47:1,这些结果表明J-聚集体中,染料与其反离子形成了盐型的总体。     

CONCENTRATION, SOURCE OF MANGANESE AND IRON IN FERROMANGANESE NODULES AND THE RELATIONSHIP BETWEEN NODULES AND SEDIMENTARY ENVIRONMENTS IN NORTH PACIFIC REGION

The concentration, source of manganese and iron in ferromanganese nodules and therelation between nodules and sedimentary environments are discussed in detail by asynthetical study on chemical information of ferromanganese nodules and correspondingsediment, pore water and geological, biological (bacteria) information in 26 stations fromthe North Pacific region (7- 13°N, 178- 165°W). The result shows that (i) the concen-tration and distribution characteristics of magnese and iron in ferromanganese nod-ules differ in different types of nodules, however, the concentration decreases with theincrease in grain sizes of nodules; (ii) the source of iron in different types of nodulesis basically the same, i. e. the slow sedimentation of overlying water; (iii) manganesein nodules comes mainly from the diffusion of Mn~(2+) in the pore water, and Mn~(2+) fromthe reduction of Mn~(4+) in sediments by the medium of bacteria. As the distribution of bac-teria is believed to be strongly affected by the sedimentary envi     

蛇笼树脂的合成及其对腈纶纺丝浴液杂质的分离

蛇笼树脂的合成及其对腈纶纺丝浴液杂质的分离朱常英，晏良增，李连荣，左榘（南开大学化学系天津３０００７１）关键词蛇笼树脂，离子阻滞，功能基配对率，腈纶纺丝浴液蛇笼树脂又叫蛇笼聚电解质或延迟离子交换树脂Ｉ‘］．它的概念和名称是首先由ｉｉｉｔｅｈ等人提出来...     

PRELIMINARY RESEARCHES ON LICHENOMETRIC CHRONOLOGY OF HOLOCENE GLACIAL FLUCTUATIONS AND ON OTHER TOPICS IN THE HEADWATER OF URUMQI RIVER, TIAN-SHAN MOUNTAINS

This paper introduced briefly the research results on lichenometry of the Holoceneglacial fluctuations in the headwater of the Urumqi River, in the central TianshanMountains and discussed the histories of the Holocene glaciers and the climate. It isconsidered that lichenometry is one applicable method for dating the mid- and late-Holocene deposits in the cold and mountainous regions. Rhizocarpon geographicum (L.)DCand Xanthoria elegans (Link.) Th. Fr. could be used for dating the deposits of about 4500and 500 a B.P. respectively. There existed at least four periods of glacial advances whichoccurred before about 5700, 4100, 2800 and 403- 74 a B. P. respectively with the firstperiod the longest. Little Ice Age includes three stages of glacial advances which endedbefore about 403, 208 and 74 a B. P. respectively with the second stage the maximum.During the general Holocene warming processes, there existed at least four cold peri-ods which ended before about 5700, 4100, 2800 and 420- 91 a B.P. respectively,     

ALGAL, SPORES AND POLLEN ASSEMBLAGES FROM LATE PLEISTOCENE IN THE EAST PART OF THE CHINA SEA AND THEIR PALEOENVIRONMENTS

The paper deals with fossil spores, pollen and algae from the sediments of 70,00-12,000a B. P. in the eastern sea area of China, distinguishing three spores, pollen and algal zones. Zone Ⅰ indicates that the climate was cold, the sea level was lower, the continental shelf of theDonghai Sea (the East China Sea)was exposed as the plain with various grasses thickened and manylakes andswamps dotted in which lived abundant freshwater algae of Pediastrum, Zygnema, etc.The hills in the continental margin were covered by the dark coniferous forests of Abies, Piceaand Pinus. The climate of Zone Ⅱ was warm, resulting in the sea level rising and the con-tinental shelf submerged as neritic environment with a variety of diatoms, dinoflagllate andDictyocha. The vegetation of the hills in the continental margin became mixed forests ofconiferous and broad-leaf trees mainly composed of Pinus and Quercus. Zone Ⅲ indicatesthat the climate became cold again and the continental shelf was exposed as plain with thesame lan     

用铜物理显影的多级放大成像过程Ⅲ.影像中铜和银的分布及明胶对Au3+的还原

本文研究了铜物理显影后影像中铜和银的分布以及在非影像区明胶对Au³⁺的还原作用。铜含量随着影像深度的增加而增加,银含量却随着深度的增加而减少。Ag3d结合能向低值位移说明影像内部的银处于单原子和多原子的混合状态,但是影像表面的银却为单原子状态,如果铜物理显影进行得足够长,铜最终会将银全部遮盖。在这以后的铜物理显影是铜的自催化过程,样片浸入氯金酸溶液中后,非影像区中吸收的氯金酸量大大高于影像区,因而铜的沉积速度在非影像区也比影像区大得多。明胶能还原Au³⁺.还原过程可分为两步:第一步由Au³⁺还原成Au⁺,这一步在室温下是快反应;第二步由Au⁺还原成金,这个反应比较慢,Au⁺和Au在物理显影中可作为催化核,使铜在非影像区沉积。     

两亲两嵌段共聚物PS-b-PAA合成及其在溶液中的形态和纳米聚集结构形成

采用了ATRP方法合成了由苯乙烯及丙烯酸组成的两亲两嵌段共聚物PS b PAA ,对它们的结构组成进行了详细表征 .用荧光探针方法以二甲基氨基黄酮类化合物为探针测定了这类两亲高分子化合物的类胶束形成时的临界浓度 .并对它们所形成的特殊胶束形态通过电镜观察 ,清楚的看到在纳米线条形成过程中由纳米小球向纳米线的转变     

RAMAN SPECTROSCOPY OF C,H,L AND LL CHONDRITES AND ITS SIGNIFICANCE IN EXPLORING THE FORMATION ENVIRONMENTS OF METEORITES AND THEIR TAXONOMY

The comparison of Raman spectra of the chondrites (C, H, L, LL) has confirmed thatthere exist two types of meteorite carbon: one is the primary carbon present in carbonaceouschondrites (c) and the other is the secondary carbon contained in ordinary chondrites (H, L,LL). The parameter of order (I_G/I_D intensity ratio, similarly hereinafter) of primary car-bon tends to decrease with increasing petrologic type and it can reflect the temperature ofdust carrier at the time plasma gases in the early nebula were condensed to form primarycarbonaceous material and the hydrogen content in primary carbonaceous material. This kindof primary carbonaceous material maybe has not experienced late stage thermometamorphismwithin the parent body of chondrites, indicating that the carbonaceous chondrites wereformed and retained in the low temperature region of the solar system. The parameter oforder of the secondary carbon tends to increase with increasing petrologic type and it can re-flect the degree of graphitization o     

DISTINGUISHING OF TWO VOLCANIC ROCK SERIES IN THE LANCANG GROUP, YUNNAN PROVINCE, SW CHINA AND ITS GEOLOGICAL IMPLICATION

The detailed study on petrochemistry and geochemistry shows that meta-volcanics from Huimin and meta-basalts from Suyi belong, respectively, to different volcanic series. The former is of non-alkalic volcanic series and the latter is of straddle A-type alkslic series. Based on their geochemical characteristics of REE, LIL, HFS and Nd, Sr isotope elements, we suggest that Huimin volcanics were formed in an island arc setting and Suyi basalts were formed in a back-continental arc extensive setting. These two volcanic series have not petrogenic relationship.     

INTRODUCTION, EXPRESSION AND REGENE-RATION OF THE TiT-DNA GENES IN CULTURED CELLS FROM Hyoscyamus muticus +Nicotiana tabacum SOMATIC HYBRIDS

After the cultured cells from Hyoscyamus muticus + Nicotiana tabacum somatic hybridswere cocultivated with different virulent strains of Agrobacterium tumefaciens harboringoctopine- type Ti plasmid or nopaline- type Ti plasmid using the transformation procedurein vitro developed in the present investigation, the TiT- DNA genes were introducedinto the host cells. The onc genes and ocs or nos genes located on TiT- DNA were expres-sed in transformed colonies derived from the cocultivated cells. Although the platingefficiencies of recipient cells were reduced by the agrobacterial treatment, the frequenciesof phytohormone autotrophy ranged from 33.9 to 76 .8% in the cells infected with viru-lent strains in hormone- free conditions, and the frequencies of opine synthase activityamounted to 9.7- 47 .5%. Teratomatous shoots were regenerated from the transformed col-onies. During the course of culture the shoots were no longer to lengthen when theygrew up to 1 -3 cm in length, and they could not be rooted. Follo