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1.
The West-East pipeline project attracted the attention from all over the world for its long distance, huge diameter, complex geographic conditions, and diversified welding techniques being applied. In this paper the detail welding process and procedures used in the project are discussed and the distinguished achievements on welding techniques of China pipeline construction are described.  相似文献   

2.
华莹 《科技信息》2012,(30):186-187
Of Time and the River is a famous novel written by American novelist–Thomas Wolfe who was a major American novelist of the early 20th century.His books are well received among Chinese readers.In the novel—Of Time and the River,we can find Wolfe’s frequent use of long sentences.In this paper,the skills of translating long sentences and the ways of analyzing sentence structures are discussed by several examples selected from the novel.Based on my own translation,we can find the importance of sentence structure analysis in translating long sentences.  相似文献   

3.
The Liuqu Conglomerate, situated to the south of Yarlung Tsangbo Suture Zone (YTSZ), is a suit of molasse formed in a foreland basin of the Himalayan orogenic belt after the collision between the two plates of the Indian and Eurasion. It is of great significance in constraining the younger limit time of the collision of the two plates and providing stratigraphic evidence to reveal the post?collisional tectonic evolution and uplifting history of the Tibet plateau. However, the age of this molasse suit and its correlation to other synchronous strata distributed in southern Tibet have been in great disputes for a long time. Especially in recent years, argues on its ages are growing violently with the recognition of the great sedimentary tectonic significances of this molasse. During the field work carried out recently on this molasse suit, a lot of plant fossils were found preserved in fairly good conditions in the upper part of this strata, which is of great help in determining its age. By identification, the assemblage of the plant fossils belongs to a tropic to subtropic flora developed in the southern margin of the Northern Hemisphere supercontinent during the Middle to Later Eocene, which can provide good constraint on its formation age. This paper is to give a brief introduction of the plant assemblage and its age, and to discuss their tectonic significances.  相似文献   

4.
Through the numerical modeling of temperature field for Blast Furnace (BF) lining and stave coolers, it can tell designers how to design a cooler which the hot surface temperature is less than its critical temperature under very high heat flux. Applying low heat resistance lining and staves cooler to BF is good for a layer of slag skull frozen on the hot surface of cooling stave. As long as the slag skull can stand, the furnace wall is stable and the heat loss of furnace does not increase. This is the basic principle for designing long campaignship BF.  相似文献   

5.
In order to obtain rice monotelosomic, the progeny of 24 telotrisomics, derived from an indica rice variety, Zhongxian 3037, were screened. The variants that differed morphologically from the diploids and the original primary trisomics as well as the telotrisomics were collected for cytological identification. The variants with 24 chromosomes were selected according to the prometaphase chromosomes. From these variants, three monotelosomies with one chromosome arm deletion in each were verified by fluorescence in situ hybridization (FISH) using a rice centromeric BAC clone of 17p22 as a marker probe. The three monotelosomics were derived from telotrisomic 1S, 4L and 11L, respectively. Further identification was conducted on the prometaphase or pachytene chromosomes of the three variants, which were probed with the same centromeric BAC clone together with the corresponding chromosome arm specific makers, a0059H02 (on the short arm of chromosome 1), a0034E24 (on the long arm of chromosome 4), and a0071H11 (on the long arm of chromosome 11). The results indicated that the telocentric chromosomes in the three monotelosom. ics were derived from their respective corresponding telotrisomics. According to the telocentric chromosomes of the variants, they were monotelosomic 1S (one long arm of chromosome 1 was lost), monotelosomic 4L (one short arm of chromosome 4 was lost) and monotelosomic 11L (one short arm of chromosome 11 was lost), respectively.  相似文献   

6.
Chang'E-3 landed on the east of Sinus Iridum area on December 14, 2013, performing China's first successful soft landing on the lunar surface. We present the results on precision orbit determination and positioning of the lander and the rover. We and methods used to achieve period December 2-21, 2014. describe the data, modeling, position knowledge over the In addition to the radiometric X-band range and Doppler tracking data, delta differential one-way ranging data are also used in the calculation, which show that they strongly improve the accuracy of the orbit reconstruction. Total position overlap differences are about 20 and 30m for the 100km × 100km and 100 kmx 15 km lunar orbit, respectively, increased by ,- 50 % with respect to CE-2 and at the same level as other lunar spacecrafts of recent era such as SELENE and lunar reconnaissance orbiter (LRO). The position error of the soft landing trajectory is less than 100 m. A kinematic statistical method is applied to determine the position of the lander and relative position of the rover with respect to the lander. The position difference of the lander is better than 50 m compared to LRO photograph result. Compared with the delta very long baseline interferometry (VLBI) group delay between the lander and the rover, the delta VLBI phase delay can improve the relative position of the rover from ~ 1,000 to ~1 m.  相似文献   

7.
The Great Gatsby is considered as F.Scott Fitzgerald's most important book.This paper will concentrate on the symbolic meaning of Gatsby's tragedy-the end of the mythical American dream.Gatsby's personal experience approximates the whole of the American dream.This paper gives a detailed analysis on the formation of his dream,his great efforts in realizing his dream and his disillusionment.  相似文献   

8.
Some notes on sustainable development and scientific outlook on development were given. It is addressed that the mission of higher education to contribute to sustainable development should be reinforced and further expanded. The present situation of China's higher education and the improvements required were analyzed. Two modes of thinking (reductionism and holism) and the relationship between the mode of thinking and the mode of development were discussed. The change in the mode of thinking is the key point for Chinese higher education, and more intensive reform of teaching affairs is necessary. A proposal of the revision of China's Higher Education Act and University Constitutions was put forward.  相似文献   

9.
It has been long discussed already about the characteristics of the recent earthquake of the Xiamen-Jinmen district. However,attention should be paid to that a large shock unexpected before such as the 1999 Chi-Chi earthquake in Taiwan west plain would take place in this area and its neighborhood, affecting the stability of the construction during the long duration after completion and usage of the future Xiaman-Jinmen Bridge. The probability of such case should be considered from studying the earthquake mechanism of the surrounding regions: The Taiwan Strait basin, Taiwan region (Taiwan island) and Fujian coastal region respectively. In this paper the features of earthquakes which occurred and will occur in any one of these three districts and then their influences on the construction of the future XiamenJinmen Bridge are described and discussed.  相似文献   

10.
The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The major species of iron on the surface were oxides, sulfate, silicate,FeOOH and minor part sorbed on SiO2/Al2O3. Sulfate is the dominant species of sulfur on the surface. SiO2 and Al2O3 are the main components of Si and Al on the surface respectively.One of the most important findings was that the Fe(Ⅱ) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 20, 2002, while Fe2(SO4)3,one of the Fe(Ⅲ) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe enriched on the surface of aerosol particles. Fe(Ⅱ) accounted for 1.3%-5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to support the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.  相似文献   

11.
Gatsby’s dream is a typical American Dream.His failure signified the decay of the American post-war spirit.His death belled the alarm for the other disillusioned people from fantasy dreams and set them to reconsider the social reality.This thesis would discuss the collapse of the Gatsby’s dream and that of American dream based on the book plot and the background of 1920s.  相似文献   

12.
The propagation of HF waves in IAR can produce many nonlinear effects, including the modulation effect of IAR on HF waves and the Doppler effect. To start with the dependence of the ionospheric electron temperature varia-tions on the Alfven resonant field, We discuss the mechanism of the modulation effect and lucubrate possible reasons for the Doppler effect. The results show that the Alfven resonant field can have an observable modulation effect on HF waves while its mechanism is quite different from that of Schumann resonant field on HF waves. The depth of modulation of IAR on HF waves has a quasi-quadratic relation with the Alfven field, which directly inspires the formation of cross-spectrum between ULF waves and HF waves and results in spectral peaks at some gyro-frequencies of IAR. With respect to the Doppler effect during the propagation of HF waves in IAR, it is mainly caused by the motion of the high-speed flyer and the drifting electrons and the frequency shift from the phase vari-ation of the reflected waves can be neglected when the frequency of HF incident wave is high enough.  相似文献   

13.
Dust-storm is a kind of severe weather, which has comprehensive and significant impacts on socioeconomic development and people‘s livelihood. Enhancing the abihties of dust-storm monitoring, predicting and service will be of great benefit and the important significance to China and its people. At present, the comprehensive operation on dust-storm monitoring, predicting and service is still in a preliminary phase, the abilities of operation can‘ t meet the needs of implementing the real-time and quantitative monitoring and providing the efficient service. The implementation of the project of dust-storm monitoring, predicting and service system will greatly improve the service ability and level for tile sustainable development and make a greater contribution to build the better-off society. The first phase project mainly involves monitoring subsystem, predicting, warning and service subsystem; communications and transmission subsystem, etc. In the first phase construction a series of major measures should be taken to address project overall benefits, such as making better use of current monitoring resource, taking into account the standards of data format and project integrative and extensive abilities and so on.  相似文献   

14.
The relics of ancient rice have been regarded as the most important objective evidence of the origina- tion and spread of rice cultivation.Based on the records of 280 rice relics sites and the rice cropping regionalization as well as the distribution map of paddy soils,the current study compiled the temporal and spatial distribution map of ancient rice distribution in China.The map shows that the distribution of ancient rice is spatially extensive and meantime comparatively concentrated,temporarily covering a long and relatively continuous time-span.The rice relics in the Central China double and single rice cropping regions are among the earliest and the most abundant ones,possessing continuity in time sequence.Combined with the discovery of ancient rice and paddy filed relics,soil micromorphology, pollen combination and element geochemistry,it is suggested that Central China was the origin center of rice cultivation in China.Rice had been spread to the rest part of China in three major waves,also to the East Asian part like Korea and Japan.The temporal and spatial distribution of ancient rice reflects the past environmental change,which is also meaningful to the current rice regionalization and plan- ning as well as food security in China.  相似文献   

15.
Based on the five-year long dynamic tracking and investigation of the peasant households of the Lishu village, the influences by small town construction on the economy and employment of the original peasant households are discussed. On the one hand, small town construction plays a positive role in adjustment of the industrial structure of the original peasant households and in the transfer of their employment towards non-agricultural industries. On the other hand the economic growth of the original peasant households is not so well sustainable, and is so fluctuating. Moreover,the unbalance of income distribution of the said households has been furthered, and small town construction has made the existing labor surplus of the original peasant households more serious, particularly the women labor surplus.  相似文献   

16.
17.
The air-flow's states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bulked continuous filament (BCF)),and the effect of air-flow on the process and quality of chemical fiber is studied,and the action of mechanics and heat on the bulked continuous filament are calculated.  相似文献   

18.
Based on the analysis of carbonate content and loss on ignition for a long sediment core (737 m in length) drilled in Heqing, the orbital scale evolution of the Southwest Monsoon is revealed, by using overlapped spectral analysis and filter methods. It is shown that the obliquity cycle and precession cycle are the key factors for the Southwest Monsoon evolution and that the change of the global ice volume and the uplift of the Qinghai-Tibetan Plateau also impose great influences on it.  相似文献   

19.
Palynological studies on the Vitab?ck Clay help resolve the position of the Jurassic-Cretaceous boundary in southern Sweden. Well-preserved assemblages of terrestrial pollen and spores, together with abundant algae (Botryococcus), and for the first time, dinoflagellates have been identified in the Vitab?ck Clay. A Berriasian age is corroborated for the Vitab?ck Clay based on the palynological data; the Jurassic-Cretaceous boundary being placed around the contact of this unit with the underlying “Nytorp Sand”. The terrestrial vegetation was dominated by coniferous forest with an understorey of ferns in a warm, temperate climate. The palynoflora shows compositional similarities to the Northern Chinese Floral Province and especially the Jehol Group. The majority of the Vitab?ck Clay represents a moderate-to low-energy paralic succession. However, the basal part of the unit incorporates anomalously coarse material of mixed terrestrial and marine origin. This sedimentary package is herein interpreted to represent tsunami deposits and is similar to coeval tsunami-related deposits in France.  相似文献   

20.
In Toni Morrison's works ,there seems to be an eternal theme——the cruelty of black American peoples' fate and the conflict between black culture and white culture. Black culture is in an inferior position for a long time. In Morrison's opinion,the blacks can only survive in the white -dominated world on condition that they hold their own cultural root. And on the other hand,there is another way people should seek,which is to realize tolerance and compatibility of the two cultures. In this speech,Morrison again expounded the relation between the two cultures and expressed her wish that black culture could be admitted and respected by the white people.  相似文献   

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