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1.
The World Year of Physics (2005) is an international celebration to commemorate the 100th anniversary of Einstein’s “Annus Mirabilis.” The United Nations has officially declared 2005 as the International Year of Physics. However, the impact of Einstein’s ideas was not restricted to physics. Among numerous other disciplines, Einstein also made significant and specific contributions to Earth Sciences. His geosciences-related letters, comments, and scientific articles are dispersed, not easily accessible, and are poorly known. The present review attempts to integrate them as a tribute to Einstein in commemoration of this centenary. These contributions can be classified into three basic areas: geodynamics, geological (planetary) catastrophism, and fluvial geomorphology. Regarding geodynamics, Einstein essentially supported Hapgood’s very controversial theory called Earth Crust Displacement. With respect to geological (planetary) catastrophism, it is shown how the ideas of Einstein about Velikovsky’s proposals evolved from 1946 to 1955. Finally, in relation to fluvial geodynamics, the review incorporates the elegant work in which Einstein explains the formation of meandering rivers. A general analysis of his contributions is also carried out from today’s perspective. Given the interdisciplinarity and implications of Einstein’s achievements to multiple fields of knowledge, we propose that the year 2005 serve, rather than to confine his universal figure within a specific scientific area, to broaden it for a better appreciation of this brilliant scientist in all of his dimensions.  相似文献   

2.
HUMANS are undoubtedly the most dominant species the Earth has ever known. In just a few thousand years we have swallowed up more than a third of the planet's land for our cities, farmland and pastures. By some estimates, we now commandeer 40 per cent of all its productivity. And we're leaving quite a mess behind: ploughed-up prairies, razed forests, drained aquifers, nuclear waste, chemical pollution, invasive species, mass extinctions and now the looming spectre of climate change. If they could, the other species we share Earth with would surely vote us off the planet.Now just suppose they got their wish. Imagine that all the people on Earth - all 6.5 billion of us and counting - could be spirited away tomorrow, transported to a re-education camp in a far-off galaxy. (Let's not invoke the mother of all plagues to wipe  相似文献   

3.
IntroductionChlorophenolsarerankedhighamongpollutantsintheenvironmentowingtotheirhightoxicity ,strongstench ,andhighsolubilityinwater.Asfarasmono chlorophenolsareconcerned ,therearethreeisomers:ortho ,para andmeta .Itwasreportedthattheisomershavesimilartoxi…  相似文献   

4.
49171058D012249171057D012249171059D012449171砚双)D012549171061D012549171062D012549101015DO125A quantitative researeh on the anthroPologlcal eflb=t 5 in the Pro溉5 ofsandyland desertilicationYang GenshengLanZhou Institute of Desert Researell,Chinese Academy of Scien璐 1992.01一1995.12Research of thet心tment dlr。沈ion of the叨一vironrnent in the land develo卜ment一taking the large and the smalX止gkai lakes as examplesZhang DajunHeilongj边ng Scient饭e Researcn Institute of Env加nmental…  相似文献   

5.
CharacteristicsofchangeofhumicsubstanceinsoilindegradedgraslandsShengXuebinResearchCenterforEcoEnvironmentalSciences,Chinese...  相似文献   

6.
The reaction mechanism of 3-chlorophenol with OH, H in aqueous solution was studied by transient technology.The 3-chlorophenol aqueous solutions have been saturated with air or N2 previously.Under alkaline condition,the reaction of OH radical with 3-chlorophenol produces 3-chlorinated phenoxyl radical ,with the absorption peaks at 400 nm and 417nm.Under neutral condition,the reaction of OH radical with 3-chlorophenol produces OH-adduct with the maximal absorption at about 340 nm.And in acid solution,the reaction of H with 3-chlorophenol produces H-adduct with the maximal absorption at about 320nm.3-chlorophenol is compared with 4-and 2-chlorophenols from the free radical pathways.The results show that the positions of chlorine on the aromatic ring strongly influence the dehalogenation and degradation process.  相似文献   

7.
Biodegradation of mixture of VOC''''s in a biofilter   总被引:3,自引:0,他引:3  
IntroductionDeterioratingatmosphericairqualityhasresultinginmorestringentregulationsarebeingenforcedtocontrolairpollutants .Volatileorganiccompounds(VOCs)areamongthenewclassofaircontaminantsgeneratedfromavarietyofindustrialsources .Effortstocontroltheemis…  相似文献   

8.
1 IncreasingenvironmentalproblemscallfortechnologicalsolutionsWiththerapideconomicgrowthinthepasttwodecades,allthemajorenvironmentalproblemsofworldwideconcernhaveappearedinChinainonewayoranother.Theyaremainlyreflectedinsoilerosion,desertification,bi…  相似文献   

9.
Continuous measurements of the methane flux from rice fields in Hangzhou,eastern China,arid Leshan,Sichuan Province,were carried out for 3 years.The results show that the methane flux from rice fields has a strong diurnal variation which may be explained by the soil temperature effects and rice plant growing activities,and that the day-mean flux has a large seasonal variation which may be related to soil temperature and the availability of organic substrate in the soil.An overall sources of methane for China are estimated while the rice fields are major sources,and the sewage tmatment is an important source of methane in China that has not been measure.Sewage in China is often treated in cesspools,which are similar to the biogas pits.However,no methane is recovered from such cesspools.We estimate that the total flux of methane from such sources may be of the oidcr of 10 Tg/a.The total emissions of methane from sources in China are estmmted to be about 40±lOTg/a.  相似文献   

10.
49201015D0123The researeh about the theory and methodology of the grey modelling,P lanning and assessment of the regional water environmental qualityZeng GuangmingHunan University 1993.01一1995.1249201016D0125The last interglaelal loess reeord in Lanzhou and Wudu areas and theglobal elimate ehangesDai XuerongLanzhou University 1993.01一1995.1249271062DO 1 23Studies on thePollution totalwater environmental eaPaeityemission eontrol for rivers inreg ionalization and the waterChinaWang Hua…  相似文献   

11.
EnvironmentalgeochemicalfeaturesofarsenicinsoilinChinaWengHuanxin,LiuYunfengDepartmentofEarthSciences,ZhejiangUniversity,Hang...  相似文献   

12.
The impacts of petroleum contamination on the litter decomposition of shrub–grass land would directly influence nutrient cycling, and the stability and function of ecosystem. Ten common shrub and grass species from Yujiaping oil deposits were studied. Litters from these species were placed into litterbags and buried in petroleum-contaminated soil with 3 levels of contamination (slight, moderate and serious pollution with petroleum concentrations of 15, 30 and 45 g/kg, respectively). A decomposition experiment was then conducted in the lab to investigate the impacts of petroleum contamination on litter decomposition rates. Slight pollution did not inhibit the decomposition of any litters and significantly promoted the litter decomposition of Hippophae rhamnoides, Caragana korshinskii, Amorpha fruticosa, Ziziphus jujuba var. spinosa, Periploca sepium, Medicago sativa and Bothriochloa ischaemum. Moderate pollution significantly inhibited litter decomposition of M. sativa, Coronilla varia, Artemisia vestita and Trrifolium repens and significantly promoted the litter decomposition of C. korshinskii, Z. jujuba var. spinosa and P. sepium. Serious pollution significantly inhibited the litter decomposition of H. rhamnoides, A. fruticosa, B. ischaemum and A. vestita and significantly promoted the litter decomposition of Z. jujuba var. spinosa, P. sepium and M. sativa. In addition, the impacts of petroleum contamination did not exhibit a uniform increase or decrease as petroleum concentration increased. Inhibitory effects of petroleum on litter decomposition may hinder the substance cycling and result in the degradation of plant communities in contaminated areas.  相似文献   

13.
This study investigated the electrokinetic(EK)behavior of multiple chlorobenzenes,including 1,2,3,4-tetrachlorobenzene(TeCB), 1,2,4,5-tetrachlorobenzene(i-TeCB),and 1,2,3-trichlorobenzene(TCB)in contaminated clayed soils.The effect ofβ-cyclodextrin(β- CD)on the EK removal of the chlorobenzenes was studied.The largest removal was obtained when Na_2CO_3/NaHCO_3 buffer was used as anodic purging solution withoutβ-CD.The removal efficiencies were related to the aqueous solubilities of chlorobenzenes. With the same cumulative electroosmotic flow,greater solubility led to higher removal efficiency.The addition ofβ-CD inhibited the EK removal efficiency of all chlorobenzenes.The inhibition increased with the increase ofβ-CD concentration.With the sameβ-CD concentration,the inhibition increased with the rise of electric potential.It was found that the inclusion compounds betweenβ-CD and chlorobenzenzes were less soluble than chlorobenzenes.The formation of the less soluble inclusion compounds reduced the aqueous solubility of chlorobenzenes and led to the partial immobilization of the chlorobenzenes that desorbed from soil.It was feasible to use the EK technology to remove ehlorobenzenes in contaminated soils using water as the anodic flushing solution.The addition ofβ-CD was not recommended for the EK removal of chlorobenzenes.  相似文献   

14.
Gas chromatography with ambient temperature injection and frozen-trapped techniques was used to determine the atmospheric concentrations of halocarbons over Beijing. Halogenated compounds such as CFC-11, CFC-12, CHCl_3, CCl_4, CH_3CCl_3, CHCl =CCl_2, and CCl_2=CCl_2 were measured and their concentrations are 109±8, 234±13, 47±22, 97±24, 88±29, 11±1 and 17±3 (pptv), respectively.  相似文献   

15.
The crystal growth of hydroxyapatite (HAP) seeds in presence of the abnormal collagen secreted by the chondrocyte grown in media containing free radical sources or fulvic acid and the type II collagen (pig cartilage) damaged by · OH and fulvic acid(FA) from potable water in endemic region of Kaschin-Beck disease (KBD) was studied. The results showed that in the former case, the abnormal collagen rich in type I collagen promoted mineralization in contrast with the type n collagen. The oxidatively damaged type II collagen became less inhibitive or even promotive. In all cases, the reaction followed a second order kinetics. The powder X-diffraction analysis and SEM observation indicated that the damaged type II collagen lowers the crystalinity in the beginning and made the final crystal more agglomerated. All the results showed that the abnormal and the damaged cartilage matrix affected the bimineralization and was likely to have played an important role in the development of KBD.  相似文献   

16.
IntroductionHealthhazardsfrommercuryintheenvironmenthavecausedrestrictionsintheuseofmercuryandastrictercontrolofthereleaseofmercuryfromindustrialandotheruses.Butatthesametimethesesourcesofmercuryhavebeensubjectedtoregulation ,twonewsourceshaveappeared …  相似文献   

17.
The degradation of pesticide 1-(2-chlorobenzoyl)-3-(4-chlorophenyl)urea(CCU)in water and its accumulation and metabolism in fish were studied using HPLC method.The results of acute toxicity of both CCU and its naetabolites were also reported.The research demonstrated that CCU degraded quickly in aerobic aquatic environment and primary metabolites of CCU were 4-chlorophenyl urea and orthochlorobenzoic acid.Microorganisms play an important role for the degradation of CCU in water.Both the parents compound and its metabolites were not lethal to fish in tested concentration.The accumulation of CCU in fish was sunilar to that of dillubenzuron.The esterase in fish liver which could metabolized CCU was identified.The primary enzymatic degradation products of CCU is the same as that in water.  相似文献   

18.
全球范围内的洋中脊玄武岩 (MORB)玻璃及气泡具有均一的CO2 /3He比率(CO2 摩尔数与3He摩尔数之比 ) ,为 ( 2~ 7)× 1 0 9,这表明通过洋中脊体系释放的幔源气体具有基本恒定的CO2 /3He比率。地幔脱气的机理研究表明 ,MORB中的该比率反映的是初始MORB岩浆的挥发份特征 ,而气泡在MORB岩浆中的成核、生长和上升的活动过程所造成的CO2 -3He的分离是很有限的 ,这说明幔源气体具有特征的CO2 /3He比率。匈牙利潘诺尼亚盆地等一系列的研究实例表明 ,幔源气体的CO2 /3He比率特征能够可靠地估计地幔脱气的通量 ,并为大陆地区构造拉张背景下的地幔脱气研究提供了一个可靠的约束条件。  相似文献   

19.
20.
1 Determinationoftotalmercuryandspeciationofmercurycompoundsinatmosphere1.1 DeterminationoftotalmercuryAsamplingtrainconsistingofafiltertoretain particulatephasemercuryfollowedbyanabsorbenttrapwhichretainstotalgaseousmercuryisusedfordeterminationoftota…  相似文献   

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