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1.
We clarify the way in which cosmological perturbations of quantum origin, produced during inflation, assume classical properties. Two features play an important role in this process: First, the dynamics of fluctuations which are presently on large cosmological scales leads to a very peculiar state (highly squeezed) that is indistinguishable, in a precise sense, from a classical stochastic process. This holds for almost all initial quantum states. Second, the process of decoherence by interaction with the environment distinguishes the field amplitude basis as the robust pointer basis. We discuss in detail the interplay between these features and use simple analogies such as the free quantum particle to illustrate the main conceptual issues.  相似文献   
2.
从雍正视永明延寿为历代禅德之最,视永明延寿为心心相印者,极为重视永明延寿著作之刊刻流布及以永明延寿思想为其评判的标准与依据等方面,可以见出雍正皇帝与延寿禅师在禅学思想上的密切联系。进而根据清初社会状况及佛教尤其是禅宗演变的大背景,就雍正对永明延寿禅师的极力推崇与高度评价的原因及影响作出系统分析。  相似文献   
3.
Historical perspectives for the chemistry of diene complexes of early transition metals developed at Osaka University in the period after 1970s were reviewed briefly and personally. Preparative chemistry of this field commenced from the magnesium-diene 1:1 compounds and quickly extended to almost all the early transition metals. By the studies operated together with other researchers, unique features of these diene complexes, especially their bonding and structure, selective reactions, and catalysis performances are described.  相似文献   
4.
清末民初,伴随着中国文化及乡村教育现代化的步伐,中国乡村社会曾兴起一股"废庙兴学"之风。其最初只是一种有知之士个人在民间的自发行为;清末新政将其作为教育改革的重要内容,在全国广泛推行(实际上只是部分地区执行);民国初年,"废庙兴学"进入了一个高潮期,对推进乡村教育发挥了一定作用,但遇到了宗教文化和乡村传统势力等重重阻力。"废庙兴学"是一个多面体,它既有促进国民教育、提高民众教育程度的积极作用,又扩大了我国民间宗教文化自身的影响,加强了宗教文化的发展与壮大;也可能成为激化民众社会矛盾、危害国民教育的有效实施,其消极影响不可低估。  相似文献   
5.
野外调查和室内分析表明,牛头山地区陆良组、牛头山组应属下震旦统,其沉积相类型自下而上可划分为辫状河相、河口湾相、浅海相、滨海相、浅海相及三角洲相。“牛头山古陆”在早震旦世是不存在的。牛头山地区当时为被动大陆边缘。  相似文献   
6.
检测早孕蜕膜中淋巴细胞抗原的表达。以几种抗淋巴细胞表面标志的单克隆抗体,采用花环标记、碱磷酶抗碱磷酶(APAAP)法,对23例早孕蜕膜组织中的淋巴细胞进行测定。早孕蜕膜淋巴细胞中CD3+、CD4+、CD16+及B细胞百分率(x±s)分别为29.52±6.80%、23.60±4.80%、20.91±4.06%、1.07±1.00%、7.81±2.56%,CD4/CD8为1.2±0.2,CD3-淋巴细胞呈大颗粒淋巴细胞(LGL)形态。早孕蜕膜中存在较多CD3-、CD16-形态呈LGL的NK细胞,CD4+细胞与CD8+细胞的比值较正常外周血明显降低。  相似文献   
7.
SPORES AND POLLEN IN CRUDE OILS AND PETROLEUM SOURCE OF TARIM BASIN   总被引:1,自引:0,他引:1  
One hundred and forty-seven species of spores and pollen referred to 77 genera found in the crudeoil samples taken from four petroliferous provinces of the Tarim Basin of Xinjiang Provincehave been studied in this paper. By means of these spore and pollen fossils, the geological ages anddistribution of the petroleum source rocks of the basin are judged. Also, the principles and methodsto judge the petroleum source of a petroleum province by spore/pollen and other microfossils in crudeoils are explained.  相似文献   
8.
This paper reports two subjects. It describes LC-GC transfer by partially concurrent eluent evaporation at a greatly accelerated rate, as required for optimal compatibility with 2–3 mm i.d. LC columns and LC flow rates up to some 500 μl/min. Evaporation rates around 200 μl/min were obtained using a 0.53 mm. i.d. uncoated pre-column and an early vapor exit. A stationary-phasecoated “retaining” pre-column was used for preventing escape of volatile solutes through the vapor exit. The technique was used for the detection of food irradiation by analyzing selected radiolysis products of triglycerides, namely alkanes/alkanes and aldehydes. Extracted fat of chicken, hazel-nuts, and soup mixes was injected in LO and the relevant fractions were transferred on-line to GC. For chicken and nuts, detection of irradiation was possible down to doses below 0.5 kGy. Detection limits were higher for soup mixes due to interfering peaks.  相似文献   
9.
The reaction of Cp2Zr(L)(η2-Me3SiC2) (L = THF, py) with equimolar amounts of H2C = CMe-CHO at room temperature depends strongly on the ligands L and the solvents that are used. With L = THF, in the THF solution the insertion product 1 was isolated, whereas by conducting the reaction in n-hexane solution an alkyne substitution with 1,4-coordination of the methacrolein takes place and the binuclear complex [ 2 was obtained. In conttrast, with L = py (a stronger ligand) only a 1:1 ratio of 1 and 2 was observed in both THF and in n-hexane. At 50°C complex 1 was converted into 2 and the alkyne was eliminated quantitatively.

Complexes 1 and 2 were characterized by IR and NMR spectroscopical measurements and 1 by an additional X-ray structure determination.  相似文献   

10.
A new species of Gobiconodon is found from the Yixian Formation of western Liaonlng, China. The new taxa,G zofiae sp. nov., has a confluent opening for branches Ⅱand Ⅲ of the trigeminal nerve on the anterior lamina of the petrosal. G zofiae sp. nov. is similar to Repenomamus in having an ossified Meckel‘s cartilage connecting the lower jaws and ear region. The new species, with enlarged I^1/I1, posteriorly located infraorbital foramen and four mental foramina,distinctly differs from the other species of Gobiconodon. The new material indicates that Gobiconodon has four, not five,upper molariforms. The presence of Gobiconodon in Jchol Biota makes it possible to correlate Jehol Biota with faunas in eastern Asia and North America, and suggests the age of the Yixian Formation to be Early Cretaceous.  相似文献   
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