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“罗斯”名称的起源与古罗斯国家的形成 被引量:5
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作者 齐嘉 曹维安 《历史研究》 CSSCI 北大核心 2012年第3期111-125,191-192,共15页
俄国史学界对"罗斯"名称起源与古罗斯国家的形成问题长期存在争论。考古资料证明,沃尔霍夫—第聂伯河水道和伏尔加河水道所有关键商站的物质文化遗存本身都带有斯堪的纳维亚的遗迹;东欧平原的自然地理环境及其四邻关系决定了... 俄国史学界对"罗斯"名称起源与古罗斯国家的形成问题长期存在争论。考古资料证明,沃尔霍夫—第聂伯河水道和伏尔加河水道所有关键商站的物质文化遗存本身都带有斯堪的纳维亚的遗迹;东欧平原的自然地理环境及其四邻关系决定了东斯拉夫人最初的社会组织形式和国家形成模式;东斯拉夫人在古罗斯国家的形成过程中起到了奠基作用,他们只有等待机遇和外部动力才能建立古罗斯国家,这种机遇就是与拜占庭帝国广泛的国际商贸活动,外部动力则是来自斯堪的纳维亚的瓦良格人。 展开更多
关键词 “罗斯” 瓦良格人 东斯拉夫人 东欧平原 罗斯国家
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Some Notable Chinese in Dublin in the Mid-Twentieth Century
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作者 Kevin MACKEOWN 《Chinese Annals of History of Science and Technology》 2024年第1期78-96,共19页
The careers of three Chinese physicists,Hu Ning,Ma Shijun,and Peng Huanwu at the Dublin Institute for Advance Studies in the 1940s,and later,are described.A brief history of the foundation and operations of the instit... The careers of three Chinese physicists,Hu Ning,Ma Shijun,and Peng Huanwu at the Dublin Institute for Advance Studies in the 1940s,and later,are described.A brief history of the foundation and operations of the institute,as well as the roles in it of Erwin Schrodinger,Walter Heitler,Max Born,and others are included.Some details are given of the works carried out there.The three men's post-institute careers are described,Ma eventually in Australia,and Hu and Peng in the People's Republic of China where they became distinguished leaders of theoretical physics research. 展开更多
关键词 Dublin Institute for Advanced Studies Eamon de Valera Erwin Schrodinger Paul Dirac Max Born Walter Heitle
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The role of wild goose(Anser) populations of Russia and theTibet Plateau in the spread of the avian influenza virus 被引量:2
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作者 Mariya V.SIVAY Nikita Y.SILKO +5 位作者 Kirill A.SHARSHOV Aleksander V.PROKUDIN 李来兴 杨敏 操胜 Aleksander M.SHESTOPALOV 《Chinese Birds》 2011年第3期140-146,共7页
Wild birds of the orders Anseriformes and Charadriiformes represent a natural reservoir of low pathogenic avian influenza(LPAI) viruses(family Orthomyxoviridae).Wild geese(order Anseriformes)relating to waterfowls und... Wild birds of the orders Anseriformes and Charadriiformes represent a natural reservoir of low pathogenic avian influenza(LPAI) viruses(family Orthomyxoviridae).Wild geese(order Anseriformes)relating to waterfowls undertake extensive migration flights reaching thousands of kilometers.Isolation of the avian influenza virus(AIV) from wild geese is quite low or absent.The aims of this study are to monitor the AIV in different wild goose species,nesting on Russian territory and the Tibet Plateau and to analyze the derived data for the purpose of determining the role of these wild bird species in spreading pathogens.In our study 3245 samples from nine wild goose species in nine regions of Russia and on the territory of the Tibet Plateau(the Xizang Autonomous Region) were tested and no AIV were detected.Our study shows the non-essential role of wild geese in the spread of the AIV over long distances and reaches theconclusion that geese are probably not natural reservoirs for the primary viruses.However,further inquiry of AIV in wild goose populations is required.Studies of wild geese and AIV ecology will allow us to obtainmore information about pathogen-host relationships and to make arrangements for the maintenance ofwild goose populations. 展开更多
关键词 avian influenza virus wild geese RUSSIA Tibet Plateau
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Sirolimus inhibits growth of human hepatoma cells alone or combined with tacrolimus, while tacrolimus promotes cell growth 被引量:14
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作者 Guido Schumacher Marijke Oidtmann +6 位作者 Anne Rueggeberg Dietmar Jacob Sven Jonas Jan M. Langrehr Ruth Neuhaus Marcus Bahra Peter Neuhaus 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第10期1420-1425,共6页
AIM: Standard immunosuppression after organ transplantation stimulates tumor growth. Sirolimus has a strong antiproliferative and a tumor inhibiting effect. The purpose is to assess the effect on tumor growth of the i... AIM: Standard immunosuppression after organ transplantation stimulates tumor growth. Sirolimus has a strong antiproliferative and a tumor inhibiting effect. The purpose is to assess the effect on tumor growth of the immunosuppressive compounds sirolimus and tacrolimus alone and in combination on cells of human hepatocellular carcinoma.METHODS: We used the human cell lines SK-Hep 1 and Hep 3B derived from hepatocellular carcinoma. Proliferation analyses after treatment with sirolimus, tacrolimus, or the combination of both were performed. FACS analyses were done to reveal cell cycle changes and apoptotic cell death. The expression of apoptosis-related proteins was estimated by Western blots.RESULTS: Sirolimus alone or combined with tacrolimus inhibited the growth of both cell lines after 5 d by up to 35% in SK-Hep 1 cells, and by up to 68% in Hep 3B cells at 25 ng/mL. Tacrolimus alone stimulated the growth by 12% after 5 ng/mL and by 25% after 25 ng/mL in Hep 3B cells. We found an increase of apoptotic Hep 3B cells from 6 to 16%, and a G1-arrest in SK-Hep 1 cells with an increase of cells from 61 to 82%, when sirolimus and tacrolimus were combined. Bcl-2 was down-regulated in Hep 3B, but not in SK-Hep 1 cells after combined treatment.CONCLUSION: Sirolimus appears to inhibit the growth of hepatocellular carcinoma cells alone and in combination with tacrolimus. Sirolimus seems to inhibit the growth stimulation of tacrolimus. 展开更多
关键词 SIROLIMUS TACROLIMUS Hepatocellular carcinoma Growth inhibition Apoptosis SK-Hep 1 HEP3B
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Effect of the Zagros Mountains on the Spatial Distribution of Precipitation 被引量:3
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作者 Bohloul Alijani 《Journal of Mountain Science》 SCIE CSCD 2008年第3期218-231,共14页
In order to examine the effect of the Zagros Mountains on precipitation, first, the annual and Seasonal rainfall indices (rain days frequency, rain amount, daily rainfall intensity, and heavy rains) from 43 stations... In order to examine the effect of the Zagros Mountains on precipitation, first, the annual and Seasonal rainfall indices (rain days frequency, rain amount, daily rainfall intensity, and heavy rains) from 43 stations in 1995 - 2004 between the 30° N to 35° N parallels over the mountain range were analyzed. Second, the effect of the Zagros Mountains was studied through the computation of the spatial correlations between the precipitation parameters and the topographic indices (station site elevation, station mean elevation within a radius of 2.5 km, mean elevation of 9 blocks along each of the eight Cartesian directions, and the elevation differences of these 9 blocks from the station mean elevation). The results showed that in the cold season the maximal rainfall occurs on the upper range of west slope, while in warm season it spreads over the study area. The correlations between precipitation and elevation indices were positive on the north of the stations and negative on the south of the stations, that is, the higher elevations of the stations to the north force the uplifting of the moist air masses and increase rainfall at the stations, while the lower elevations to their south lead the movement of the moist air masses to the stations. This is due to the fact that these stations or slopes are exposed to the moist air masses coming from the Mediterranean Sea and the Persian Gulf. The heavy rain days and the summer sporadic rain events do not show significant correlations with the topographic indices. The findings indicate that the Zagros Mountains intensify the cold period frontal rains especially over the west slope and block the moist air masses from entering the interior parts of the country. Moreover, these mountains play a secondary role in creating rain days. But they are very important in the production of precipitation in the area. Therefore, their absence will decrease the amount of rainfall to their west and, in return, expand the dry climates of their west and east. 展开更多
关键词 Zagros Mountains spatial distribution of rainfall relationship between topography and precipitation Iran
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Rossby waves with linear topography in barotropic fluids 被引量:2
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作者 杨联贵 达朝究 +3 位作者 宋建 张会琴 杨红丽 侯一筠 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第3期334-338,共5页
Rossby waves are the most important waves in the atmosphere and ocean,and are parts of a large-scale system in fluid.The theory and observation show that,they satisfy quasi-geostrophic and quasi-static equilibrium app... Rossby waves are the most important waves in the atmosphere and ocean,and are parts of a large-scale system in fluid.The theory and observation show that,they satisfy quasi-geostrophic and quasi-static equilibrium approximations.In this paper,solitary Rossby waves induced by linear topography in barotropic fluids with a shear flow are studied.In order to simplify the problem,the topography is taken as a linear function of latitude variable y,then employing a weakly nonlinear method and a perturbation method,a KdV(Korteweg-de Vries) equation describing evolution of the amplitude of solitary Rossby waves induced by linear topography is derived.The results show that the variation of linear topography can induce the solitary Rossby waves in barotropic fluids with a shear flow,and extend the classical geophysical theory of fluid dynamics. 展开更多
关键词 nonlinear Rossby waves KdV equation topography effect perturbation method
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Distribution and diversity of microbial communities in meromictic soda Lake Doroninskoe(Transbaikalia,Russia) during winter 被引量:3
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作者 Evgeniya MATYUGINA Natalia BELKOVA 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第6期1378-1390,共13页
Meromictic soda and saline lakes are unique ecosystems characterized by the stability of physical,chemical and biological parameters,and they are distributed all over the world.Lakes located in regions with average an... Meromictic soda and saline lakes are unique ecosystems characterized by the stability of physical,chemical and biological parameters,and they are distributed all over the world.Lakes located in regions with average annual negative air temperature are of particular interest because of the presence of two periods with intensive and dynamic processes:the so-called biological summer and the long ice season with the biological spring.Soda Lake Doroninskoe is located in Eastern Transbaikalia(51°14′N,112°14′E) in the permafrost zone in an extreme continental climate,and is covered by ice for seven months per year.The structure and diversity of the microbial communities throughout the water column of the lake was studied by 16 S r RNA gene amplicon metasequencing.Different species with specific functions were found to dominate at different depths.Metabolically flexible bacteria with a capacity to switch between anoxygenic photosynthesis and aerobic chemotrophic metabolism dominate in soda Lake Doroninskoe. 展开更多
关键词 bacterial diversity soda lake MEROMIXIS Lake Doroninskoe 16S rRNA genes high-throughput amplicon sequencing
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Variation of Alkaline Phosphatase Activity in Sediments of Shrimp Culture Ponds and Its Relationship with the Contents of C,N and P 被引量:2
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作者 SUYuepeng MAShen DONGShuanglin 《Journal of Ocean University of China》 SCIE CAS 2005年第1期75-79,共5页
Nine enclosures (5 m x 5 m) were built in a Fenneropenaeus chinensis culture pond of Rushan Gulf in April, 2001. The probiotics and BIO ENERGIZER solution were applied for disparate treatments. Variations of alkaline ... Nine enclosures (5 m x 5 m) were built in a Fenneropenaeus chinensis culture pond of Rushan Gulf in April, 2001. The probiotics and BIO ENERGIZER solution were applied for disparate treatments. Variations of alkaline phosphatase ac- tivity (APA) and its relationship with the contents of C, N and P in sediments were studied. Results show that APA of sedi- ments increases from 3.096 nmolg-1min-1 to 5.407 nmol g-1min-1 in culture period; the bacteria biomass is not the only factor to determine APA; the contents of total P and total organic carbon have a significant positive correlation with APA, while that of total nitrogen has a negative correlation. In addition, the contents of inorganic P and organic P are not regular with APA. By comparison, TOC shows a more significant coherence with APA, meaning that organic pollution in sediments af- fects APA remarkably. 展开更多
关键词 APA N C P SEDIMENTS fenneropenaeus chinensis
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Metabolic Changes in Rats with Photochemically Induced Cerebral Infarction and the Effects of Batroxobin:A Study by Magnetic Resonance Imaging,~1H-and ^(31)p-Magnetic Resonance Spectroscopy 被引量:6
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作者 管兴志 吴卫平 +6 位作者 匡培根 匡培梓 高杨 管林初 李丽云 毛希安 刘买利 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2001年第1期59-67,共9页
Metabolic changes in rats with photochemically induced cerebral infarction and the effects of batroxobin were investigated 1, 3, 5 and 7 days after infarction by means of magnetic resonance imaging (MRI), 1H- and 31P-... Metabolic changes in rats with photochemically induced cerebral infarction and the effects of batroxobin were investigated 1, 3, 5 and 7 days after infarction by means of magnetic resonance imaging (MRI), 1H- and 31P-magnetic resonance spectroscopy (MRS). A region of T2 hyperintensity was observed in left temporal neocortex in infarction group and batroxobin group 1, 3, 5 and 7 days after infarction. The volume of the region gradually decreased from 1 day to 7 days after infarction. The ratio of NAA/Cho + Cr in the region of T2 hyperintensity in the infarction group was significantly lower than that in the corresponding region in the sham-operated group 3, 5 and 7 days after infarction respectively (P 展开更多
关键词 Animals Aspartic Acid BATROXOBIN Cerebral Infarction Magnetic Resonance Imaging Male PHOTOCHEMISTRY Photosensitizing Agents Random Allocation RATS Rats Sprague-Dawley Rose Bengal
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Periodic Structures of Rossby Wave under Influence of Dissipation 被引量:2
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作者 CHEN Zhe LI Chong-Yin FU Zun-Tao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期35-40,共6页
A simple barotropic potential vorticity equation with the influence of dissipation is applied to investigate the nonlinear Rossby wave in a shear flow in the tropical atmophere. By the reduetive perturbation method, w... A simple barotropic potential vorticity equation with the influence of dissipation is applied to investigate the nonlinear Rossby wave in a shear flow in the tropical atmophere. By the reduetive perturbation method, we derive the rotational KdV (rKdV for short) equation. And then, with the help of Jaeobi elliptie functions, we obtain various periodic structures for these Rossby waves. It is shown that dissipation is very important for these periodic structures of rational form. 展开更多
关键词 rKdV equation elliptic equation Jacobi elliptic function periodic structure rational form
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Prevalence of lactase persistent/non-persistent genotypes and milk consumption in a young population in north-west Russia 被引量:2
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作者 Yulia Khabarova Suvi Torniainen +3 位作者 Hanna Nurmi Irma Jrvel Mauri Isokoski Kari Mattila 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第15期1849-1853,共5页
AIM: TO estimate the prevalence of the lactase non-persistent genotype (C/C-23910) in a northern Russian population in accordance with ethnicity, and to evaluate self-reported milk consumption depending on lactase ... AIM: TO estimate the prevalence of the lactase non-persistent genotype (C/C-23910) in a northern Russian population in accordance with ethnicity, and to evaluate self-reported milk consumption depending on lactase activity. METHODS: Blood samples for genotyping lactase activity, defining the C/T-13910 variant by polymerase chain reaction, and direct sequencing were taken from 231 medical students of Russian origin aged 17-26 years. We analyzed milk product consumption by questionnaire which was specially designed for the estimation of milk consumption and abdominal complaints. RESULTS: We found that the prevalence of the C/C-13190 genotype in the northern Russian population was 35.6%. The other genotypes nearby C/T-13910 and associated with lactase activity were not present in the study population. The consumption of milk among people with the non-persistent genotype tended to be lower than among the lactose tolerant subjects, but was not statistically significant. CONCLUSION: An investigation of the lactase persistent genotype in a northern Russian population has not been performed before, The genotype did not affect the consumption of milk products in this population which could be explained by low consumption of milk products among the entire study population. 展开更多
关键词 C/C-13910 genotype Hypolactasia Lactasepersistence/non-persistence Lactose malabsorption Milk consumption North-west Russia
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Two-Dimensional Rossby Waves: Exact Solutions to Petviashvili Equation 被引量:1
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作者 ZHAO Qiang ZHAO Yuan LIU Shi-Kuo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期414-416,共3页
The two-dimensional (2D) nonlinear Rossby waves described by the Petviashvili equation, which has been invoked as an ageostrophic extension of the barotropic quasi-geostrophic potential vorticity equation, can be in... The two-dimensional (2D) nonlinear Rossby waves described by the Petviashvili equation, which has been invoked as an ageostrophic extension of the barotropic quasi-geostrophic potential vorticity equation, can be investigated through the exact periodic-wave solutions for the Petviashvili equation, while the exact analytical periodic-wave solutions to the Petviashvili equation are obtained by using the Jacobi elliptic function expansion method. It is shown that periodicwave 2D Rossby solutions can be obtained by this method, and in the limit cases, the 213 Rossby soliton solutions are also obtained. 展开更多
关键词 Petviashvili equation 2D Rossby waves Jacobi elliptic function
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An analysis of new generation coal gasification projects 被引量:6
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作者 Kreynin Efim Vulfovich 《International Journal of Mining Science and Technology》 SCIE EI 2012年第4期509-515,共7页
The global trends of increasing oil and gas costs have compelled coal possessing countries to start long term underground coal gasification (UCG) projects. These enhance national energy security and are among the cl... The global trends of increasing oil and gas costs have compelled coal possessing countries to start long term underground coal gasification (UCG) projects. These enhance national energy security and are among the cleanest, ecologically safest coal utilization technologies. This paper delineates the major characteristics of such technologies and analyzes technical solutions. Highlighting the desire to develop large scale industrial UCG plants, pilot level projects are presented using a new UCG method developed in Russia by Joint Stock Company Gazprom Promgaz. This method is distinct for its high controllability, stability, and energy efficiency. New, efficient technical solutions have been developed over the last 10-15 years and are patented in Russia. They guarantee controllability and stability of UCG gas produc- tion. Over one hundred iniection and gas production wells have been operated simultaneously. 展开更多
关键词 Underground coal gasification (UCG)UCC technology of the new generationStability and controllabilityClean coal technology
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Equatorward shift of annual Rossby waves in the Equatorial Pacific Ocean 被引量:1
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作者 马晓 孙澈 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第1期212-218,共7页
Annual Rossby wave is a key component of the ENSO phenomenon in the equatorial Pacific Ocean. Due to the paucity and seasonal bias in historical hydrographic data,previous studies on equatorial Rossby waves only gave ... Annual Rossby wave is a key component of the ENSO phenomenon in the equatorial Pacific Ocean. Due to the paucity and seasonal bias in historical hydrographic data,previous studies on equatorial Rossby waves only gave qualitative description. The accumulation of Argo measurements in recent years has greatly alleviated the data problem. In this study,seasonal variation of the equatorial Pacific Ocean is examined with annual harmonic analysis of Argo gridded data. Results show that strong seasonal signal is present in the western equatorial Pacific and explains more than 50% of the thermal variance below 500 m. Lag-correlation tracing further shows that this sub-thermocline seasonal signal originates from the eastern equatorial Pacific via downward and southwestward propagation of annual Rossby waves. Possible mechanisms for the equatorward shift of Rossby wave path are also discussed. 展开更多
关键词 equatorial Pacific annual Rossby wave equatorward shift Argo profiles MOAA-GPV gridded data
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Close relationship between the East Asian westerly jet and Russian far East surface air temperature in summer 被引量:1
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作者 LIN Xiao-Zhen LI Chao-Fan +1 位作者 LIN Zhong-Da LU Ri-Yu 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第3期282-286,共5页
The interannual variability of the east asian upper-tropospheric westerly jet(EAJ) in summer is characterized by the meridional displacement of its axis, or a seesaw pattern of zonal wind anomalies between the north... The interannual variability of the east asian upper-tropospheric westerly jet(EAJ) in summer is characterized by the meridional displacement of its axis, or a seesaw pattern of zonal wind anomalies between the northern and southern flanks of the EAJ. This study reveals a close relationship between the surface air temperature in the russian far east and the northern flank of the EAJ. Related to a warmer surface in the russian far east, the westerly decelerates in the northern flank of the EAJ. The relationship can be explained by a positive feedback mechanism between the surface air temperature in the russian far east and the overhead circulation: the anticyclonic circulation anomaly related to a weakened westerly in the northern flank of the EAJ induces surface warming in the russian far east and the warmer surface can in turn act as a heat source and induces a local anticyclonic circulation anomaly in the upper troposphere, therefore decelerating the westerly in the northern flank of the EAJ. The result implies that a better description of the summer surface condition in the russian far east may benefit seasonal forecasts of the EAJ and, subsequently, east asian summer climate. 展开更多
关键词 East Asian westerly jet surface air temperature Russian far East
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Recent advances on study of hadrosaurid dinosaurs in Heilongjiang(Amur) River area between China and Russia 被引量:3
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作者 Pascal Godefroit Pascaline Lauters +7 位作者 Jimmy Van Itterbeeck Yuri L. Bolotsky DONG Zhiming JIN Liyong WU Wenhao Ivan Y. Bolotsky HAI Shulin YU Tingxiang 《Global Geology》 2011年第3期160-191,共32页
Four main dinosaur-bearing sites have been investigated in latest Cretaceous deposits from the Amur/Heilongjiang Region : Jiayin and Wulaga in China ( Yuliangze Formation), Blagoveschensk and Kundur in Russia (Udu... Four main dinosaur-bearing sites have been investigated in latest Cretaceous deposits from the Amur/Heilongjiang Region : Jiayin and Wulaga in China ( Yuliangze Formation), Blagoveschensk and Kundur in Russia (Udurchukan Formation). More than 90% of the bones discovered in these localities belong to hollow-crested lambeosaurine hadrosaurids: Charonosaurus fiayinensis at Jiayin, Amurosaurus riabinini at Blagoveschensk, Olorotitan arharensis at Kundur, and Sahaliyania elunchunorum at Wulaga. Flat-headed hadrosaurine hadrosaurids are much less numerous, but appear well diversified as well: Kerberosaurus manakini at Blagoveschensk, Wulagasaurus dongi at Wulaga, and a new genus at Kundur. Theropods are represented by shed teeth and isolated bones; isolated scutes and teeth discovered at Kundur are tentatively attributed to nodosaurids. Palynological studies suggest that these sites are probably synchronous with the Lancian' vertebrate localities of western North America, which represent the youngest dinosaur faunas in this area. However, the latest Cretaceous dinosaur assemblages are completely different in the Amur/Heilongjiang region (lambeosaurines abundant, ceratopsids absent) and in western North America (ceratopsids abundant, lainbeosaurines extremely rare or absent). This probably reflects some kind of geographical barrier between both areas by Maastrichtian time rather than strong differences in palaeoecological conditions. 展开更多
关键词 Heilongjiang Province Amur Region Late Cretaceous dinosaurs HADROSAURIDAE PALAEOBIOGEOGRAPHY
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Pulling Vs. Pushing:Effect of Climatic Factors on Periodical Fluctuation of Russian and South Korean Tourist Demand in Hainan Island,China 被引量:1
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作者 CHEN Fan LIU Jun GE Quansheng 《Chinese Geographical Science》 SCIE CSCD 2017年第4期648-659,共12页
While climate is an important factor attracting tourists to certain destinations,it can also motivate people residing in a country with a harsh climate to move to another location.By applying X-12 decompositions and a... While climate is an important factor attracting tourists to certain destinations,it can also motivate people residing in a country with a harsh climate to move to another location.By applying X-12 decompositions and a panel data regression analysis,this study analyzes the pull and push effects of climatic seasonal factors between destination(Hainan Island,China) and source countries(Russia and South Korea).The findings show that climatic seasonal factors have significant pulling and pushing effects on seasonal patterns of tourism demand,with temperature being the main factor.Furthermore,the number of paid vacation days in the source country affects that country's sensitivity to climatic seasonal factors;countries with a higher numbers of paid vacation days are more sensitive to climatic conditions.Lastly,future global warming may causes the aforementioned pull and push effects to abate,which will have an unavoidable influence on tourism industries. 展开更多
关键词 seasonality climate tourism demand Hainan Island China
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Interpretation of Robert Frost's "Mending Wall" 被引量:1
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作者 ZHAO Xin-li 《Sino-US English Teaching》 2007年第6期71-74,共4页
Robert Frost is skillful at adopting symbolism and images in his poems. "Mending Wall", one of Frost's well-known poems, had been analyzed in different approaches, such as psychoanalytical approach, social approach... Robert Frost is skillful at adopting symbolism and images in his poems. "Mending Wall", one of Frost's well-known poems, had been analyzed in different approaches, such as psychoanalytical approach, social approach and structural approaches, etc. By exploring the symbol and images applied in "Mending Wall", it draws the conclusion that "the wall", symbolizing convention, is set as a barrier in human communication. 展开更多
关键词 SYMBOL IMAGE "Mending Wall" CONVENTION
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Effects of Temperature, Relative Humidity and Moisture Content on Seed Longevity of Shrubby Russian Thistle ( Salsola vermiculata L,) 被引量:1
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作者 Abdoul Aziz Niane Paul Christiaan Struik Zewdie Bishaw 《Journal of Agricultural Science and Technology(B)》 2013年第9期623-634,共12页
Salsola vermiculata is a highly palatable shrub and widely used in rangeland rehabilitation programs, but has short seed longevity. To identify the most cost effective storage method for S. vermiculata, experiments we... Salsola vermiculata is a highly palatable shrub and widely used in rangeland rehabilitation programs, but has short seed longevity. To identify the most cost effective storage method for S. vermiculata, experiments were carried out to test the effects of fruit bracts (wings), temperature regimes, seed moisture and packaging methods on storage life. Seed samples were removed from storage at monthly intervals for testing and towards the end of the experiments samples were transferred from hermetic to ambient storage conditions and tested for germination. Experiment 1 continued for 1,140 days, Experiment 2 for 720 days. For de-winged seed, high moisture content increased seed longevity, suggesting that desiccation susceptibility is one of the causes of limited longevity in this species. Most longevity regression lines of winged seeds had negative intercepts suggesting increase in germination resulting from gradual dormancy-breaking. Drying and packaging alone increased longevity by 7.6 and 3.8 times in Experiments 1 and 2, respectively. Samples kept at lower temperature and lower moisture treatments survived longer under ambient conditions. Increased longevity by drying and vacuum packaging alone can provide simple, cost effective and environmentally friendly options for rangeland rehabilitation programs. 展开更多
关键词 Salsola vermiculata L. seed storage vacuum packaging seed longevity probit analysis.
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Water Chemistry and Hydrometeorology in a Glacierized Catchment in the Polar Urals,Russia 被引量:2
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作者 STACHNIK Lukasz WALACH Piotr +3 位作者 UZAROWICZ Lukasz YDE Jacob C. TOSHEVA Zornitza WRONSKA-WALACH Dominika 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1097-1111,共15页
This study aims to determine the relationships between local meteorological conditions,proglacial river discharge and biogeochemical processes operating in a periglacial basin located in the Polar Ural mountain range,... This study aims to determine the relationships between local meteorological conditions,proglacial river discharge and biogeochemical processes operating in a periglacial basin located in the Polar Ural mountain range, Russia. Fieldwork was conducted in the catchment of Obruchev Glacier(13 km2) during the summer peak flow period in 2008. River discharge was dominated by snowmelt and changed from 3300 l s-1 to less than 1000 l s-1. The mean daily air temperatures of stations situated in the mountain tundra and near Obruchev Glacier from July 11 th to August 1st 2008 were 14.4°C and 10.3°C, respectively. The glacial river had low total dissolved solids varying from 4.5 to 9 mg l-1 and coefficients of correlation between Na+ and Cl-, K+ and Cl-, as well as NH4+ and Cl- were 0.94, 0.90 and 0.84, respectively. Rainfall events affected the snowmelt initiation and provided an essential part of the discharge during the intense snowmelt period, which occurred from July 11 th to July 18 th 2008. Data showed that Na+ and K+ in the surface water derived from snowmelt rather than chemical weathering of silicates. Also, it was obtained that NO3- derived from the melting snowpack, whereas ammonification occurring under the snowpacks was the primary source for NH4+. 展开更多
关键词 Polar Urals River discharge Nitrate Chemical weathering Periglacial basin Glacier
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