Trials and tribulations of playing the devil’s advocate

Beginning with his student days at school and college, the author describes his training at Cambridge with special emphasis on his mentor Fred Hoyle. His early experience of participating in a controversy at Cambridge played a major role in giving him the confidence to defend his scientific ideas. All through his later life he chose areas that were not part of mainstream research. These included the steady state theory and later the quasi steady state cosmology, action at a distance, noncosmological redshifts, quantum conformal cosmology, etc. After being a founding member of the Institute of Theoretical Astronomy(IOTA) at Cambridge, the author joined the Tata Institute of Fundamental Research(TIFR) in Mumbai and later moved to Pune to set up the Inter-University Centre for Astronomy and Astrophysics(IUCAA). He briefly reviews his own work and ends by pointing out the difficulties a non-conformist scientist faces in his professional life. In the conclusion, he mentions his interests in science popularization and science fiction for which he has won awards and appreciation, including UNESCO’s Kalinga Prize.     

巨早型星系的近红外谱合成

在8000至8670的波长范围内,利用一个由144颗恒星光谱组成的光谱厍,我们对57个巨椭圆和S0星系(M_B<-21)的光谱和它们的平均光谱进行了光谱合成.这个光谐库包括了光谱型为G,K和M的巨星和矮星,它具有的金属丰度[Fe/H]覆盖了-0.1到-0.5的范围,表面重力log g为1.0至5.0.光谱合成的结果表明:巨椭圆和S0星系的金属丰度约为太阳的一倍半;有效表面重力分布在3.2—4.1的范围内;矮星在8400附近光的贡献可与巨星相比较.     

DETERMINANTS OF STRUCTURE IN AQUATIC NON-PELAGIC PROTOZOAN COMMUNITIES

Although microbes have traditionally been used as models for testing ecological theory, research on the organization of these communities has largely been isolated from other areas of community ecology. Early studies indicated that microbial populations can form dynamic, interacting assemblages. Observations of distributional patterns suggest that certain deterministic forces regulate community structure. It appears that protozoans are tolerant of a wide range of environmental conditions although evidence for this is largely based on gross environmental analyses. Laboratory studies have suggested the importance of negative and positive biotic interactions in determining community membership, but little field evidence for this exists. The importance of transport processes in controlling community composition is being increasingly recognized. All three types of processes likely act to regulate the colonization and successional dynamics of these communities. A simple model is presented to promote the devel     

Validation of Foreground Emission Model using GALEX Medium Observations

The study of diffuse ultraviolet(UV) background radiation is vital in the investigation of stellar and galactic evolution. Space-based UV observations are comprised of both foreground and background radiations. The foreground emission in an observation is a result of solar contamination in the direction of observation. In our previous work, we modeled airglow(one of the major constituents of the foreground emission) as a function of10.7 cm Solar Flux and Sun Angle with great accuracy using GALEX...     

主动-被动式雷达探测雷暴源

宽波段主动－被动式雷达探测雷暴云是获得云中电状态信息的新手段,它不仅可用来确定雷暴前期大气电的发展程度,还可确定威胁飞机 (或飞行器等 )的雷暴云危险程度。在雷暴期间可确定不同尺度雷电产生的时刻和部位以及它们维持的时间。根据当时得到的资料可确定雷电活动的时空状态,并可预测雷电发展的趋势。 随着人类在空中活动的不断增多,飞机尺度和飞行速度的明显增大,飞机遭受意外雷击的飞行事故也相应增多。不仅产生过非雷暴云对邻近飞机的雷击,甚至在冬季也产生过雷击现象。这些现象产生原因与常规气象探测手段不能足够客观地评价…     

科拉超深孔下部层位独特的矿物组合

科拉超深钻在科拉群的角闪岩中打到了铁矿层和磁铁矿-钛铁矿矿石,与变质的超镁铁质岩伴生的铜-镍硫化物矿化,以及退化变质带中的低温热液铜-铅硫化物矿化,在9.5—11公里处还见到了自然金。在9.5—11公里深处,有约430米长的岩心金的含量比较高,个别超过1ppm,最高达6.7ppm,岩心的矿物学研究表明,自然金中含有大约25%的银,自然金在黑云母、普通角闪石和斜长石中呈小于10μm 的不规则的碎片和细粒,虽然金矿化在空间上与叠加在黑云母-角闪石片麻岩上的退化变质带相一致,但是,浸染状的金与变质母岩的绿泥石化、绢云母化和绿帘石化没有直接的联系。     

Anabar地盾多相变质岩中石英的显微构造与流动应力:太古宙褶皱流动与元古宙板间滑动

Anabat地盾是西伯利亚地台结晶基底的北部外露,由两种主要变质杂岩构成。2.7Ga的太古宙Anabar麻粒岩杂岩含有火山成因的紫苏斜长片麻岩和变基性岩,在某些地段含有石榴片麻岩(变杂砂岩)和变质碳酸盐岩。这些岩石遭受褶皱变形形成狭窄线型,有时呈龙骨状的褶皱,这些褶皱带宽1～5km,长10～25km,走向NW-N,倾向E-NE构成一组均匀褶皱组合,表明了由E-NE向W-NW向的区域挤压作用。 1.9Ga的元古宙Lamujka杂岩占据了地台区面积约五分之一,这是由10～30km宽的断层带对麻岩的转变而成的。最初阶段形成了角闪岩相变余麻粒岩;第二阶段形成混     

国外的辐射井

前言国际地下水协会于1969年出版了美国威廉、维·卡尔(william·v·karr)所著的“地下水一提取及设计方法”一书。该书介绍了提取地下水的各种方法,着重介绍的是辐射井。该井的钢筋混凝土井筒用沉井法     

S—型花岗岩及其在北美西南部可能缺失

已经被用来(而且目前仍在继续使用)标定澳大利亚东南部的Lachlan褶皱带(LFB)中S-型花岗岩的一些标准在本文中又做了评述,而且与北美西南部的各种过铝花岗岩进行了比较。根据一些不充分的资料,其中的某些花岗岩已被归类为S-型花岗岩。实际上在LFB中所有的体积巨大的S-型花岗岩是近地表的岩基花岗岩,它们通常与S-型火山岩组合在一起,而不与区域变质岩和混合岩相伴生。这些花岗岩强烈地过铝,堇青石的存在则为一证据。含有原生白云母的花岗岩是很少见的。由于在沉积源岩的形成过程中化学风化作用的结果,所有这类花岗岩是低Na、Ca和Sr的。北美西南部不同时代的过铝花岗岩则有明显的差异。这些花岗岩很少含有堇青石(在LFB中,为S-型花岗岩的一个标志矿物),但是其中的某些花岗岩具有进一步演化的特点,以致结晶出富含Fe—Mn的石榴石。这些花岗岩主要是二云母花岗岩,与LFB中大多数过铝花岗岩相比,其结晶作用发生在水(?)度较高及深度更深的环境下。含堇青石的火山岩(S-型)至今未见报导。北美西南的过铝花岗岩总体上来讲是高Na的。这些岩石的某些具有奥长花岗岩的亲缘性,其母岩浆似乎很象是从遭受过改造的玄武质岩石经部分熔融而产生的。局部出现的某些过铝花岗岩(边缘至准铝型)可能是由于高层位的I-型花岗岩混染所造成的。这些岩石不是S-型花岗岩。到目前为止,仍没有提供充分的证据来证实北美西南部过铝花岗岩是S-型花岗岩。