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1.
THECHARACTERISTIC,DISTRIBUTIONANDCAUSINGFACTORCOFTHEDISABLEDINHENANPROVINCE¥LinFurui(林富瑞)(HenanAcademyofSciencs,Zhengzhou4500...  相似文献   

2.
于希贤,沙露茵THEBRILLIANTGEOGRAPHEROFMINGDYNASTY,XUHONGZUANDHISCONTRIBUTIONSTOSCIENCE¥YuXixian(DepartmentofGeography,PekingUniversi...  相似文献   

3.
INFLUENCEOFSEA-AIRINTERACTIONONTHEDISCHARGEOFFLOODSEASONINTHEUPPERREACHESOFTHECHANGJIANGRIVERZhangXinping(章新平)(LanzhouInstitu...  相似文献   

4.
PRESENTSITUATION,FEATUREANDDEVELOPMENTAL IDEASOFBORDEROPENINGINXINJIANGXieXiangfang(谢香方);LiChunhua(李春华)(XinjiangInstituteofGe...  相似文献   

5.
ENVIRONMENTGEOLOGICISSUESANDSTUDYCOUNTERMEASURESABOUTCITYCONSTRUCTIONOFCHINAWuHeng(GuangxiuniversityNanning)〔Abstract〕Thestud...  相似文献   

6.
FEATURESOFSUBMARINESEDIMENTARYDIKEGROUPSINGUANGXIANDITSFORMINGMECHANISMZhangJiyan(GuangxiRegionalGeologicalSurveyingInstitute...  相似文献   

7.
THECALCULATIONOFADDITIONALSTRESSCAUSEDBYCONSTRUCTIONOFCASTINSITUPILEWITHDRIVENCASINGINSOILZhouDong(GuilinInstituteofTechnolog...  相似文献   

8.
REGULARITIES,CONDITIONSANDTHECOMPREHENSIVEPROSPECTINGMODELOFMICROGRAINED-DISSEMINATEDGOLDDEPOSITSINNORTHWESTERNGUANGXI①WangJi...  相似文献   

9.
REGULARITYANDESTIMATIONOFMETHANEEMISSIONFROMMARSHLANDINTHESANJIANGPLAIN①CuiBaoshan(崔保山)MaXuehui(马学慧)ChangchunInstituteofGeogr...  相似文献   

10.
THE NOMENCLATURE OF THE SOUTH CHINA SEA ISLANDS IN ANCIENT CHINA   总被引:1,自引:0,他引:1  
THENOMENCLATUREOFTHESOUTHCHINASEAISLANDSINANCIENTCHINA¥LiuNanwei(刘南威)(DepartmentofGeography,SouthChinaNormalUniversity,Guangz...  相似文献   

11.
The contents of nearly forty-elements in surface sediments in Jiaozhou Bay were determined using a Neutron Activation Analysis Technique(Grancini,et al.,1976;Li Peiquan et al.,1985,1986;Li Xiuxia etal.,1986).This paper's detailed discussion on only nine elements(Fe,Mn,Co,Cr,Sc,As,Sb,Zn andV)includes their distributions,concentrations,correlationships,material sources,background,etc.Based on Zavaristski's classification method,Fe,Mn,Co Cr and V belong to the second group;As and Sb to theeighth groups:Sc and Zn to the third and sixth groups.It was found that their notably good correla-tionship is mainly due to the similarity of their ionic structures and that their variation is controlled by theFe content(except Mn).The source of sediments is mainly terristrial material,and the composition ofsediment is similar to that of shale and shale+clay.The contents for a large number of ele-ments are within the scope of the background level,but there still is pollution of Zn and Cr,at least in a few stations.  相似文献   

12.
氟、氯、溴、碘等卤族元素与人体健康的关系   总被引:1,自引:0,他引:1  
卤族元素是人体的必需元素,正常情况下成人摄入量不超过F4 mg/d、C11.7~5.1g/d、I 100~200μg/d;少年不超过F 3 mg/d,儿童I1μg/kg-d,婴儿Cl0.3~1.2 g/d.过量摄入或缺乏卤族元素,都可能导致疾病的发生.而F含量0.5~1.0mg/L、C1<50mg/L、Br>100μg/L、I 10~100μg/L的饮用地下水,有利于人体健康.  相似文献   

13.
A study was conducted on Cu, Zn, Cd, Fe, Co and Ni levels in Saanich Inlet anoxic seawater. Data on the concentration of these trace metals and H2S, and other oceanographic parameters were obtained in four cruises. Equilibrium models are presented together with in situ data. The results strongly support the assumption that the solubilities of Cu, Zn, Cd, Fe, Co and Ni are controlled by bisulfide and/or polysulfide complexes. The species of Cu, Zn, Cd and Ni are shown to be Cu(S4) 2 3− and Cu(Sn4S5)3−, Zn(HS) 2 0 and ZnHS 2 , Cd(HS) 2 0 and Ni(HS) 2 0 , respectively. The solid species controlling Fe2+ and Co2+ are respectively the pyrohotites FeS and CoS. The data illustrates that thermodynamic equilibrium has been established in the H2S-controlled seawater of Saanich Inlet, and that equilibrium has not been established in the H2S−O2-coexisted seawater of Saanich Inlet. The lack of equilibrium in the H2S−O2-coexisted seawater is a result of the flushing or mixing of oxygenated seawater with anoxic water. The new species of trace metals are still in the processes of reduction and precipitation. Contribution No. 1428 from Institute of Oceanology, Academia Sinica  相似文献   

14.
Monthly investigatiom were made on the population of Chinese freshwater crab, Sinopotamon yangteskiense Bott, 1967 from April, 1984 to Match, 1985. The data on 4413 specimens show that the growth was affected mainly by temperature. During the April to November growth period, the crabs' major development occured from June through October. One year was required for a fine white oocyte to develop into a mature egg. The reproduction period was June-October. Females bearing eggs were taken from June-August, and crabs with young were found from July-October. The females reproduced once a year but could for more than one year. The number of eggs carried by a female varied greatly according to the size of the crab, ranging from 30 to 100 eggs. New-bom crabs become mature after 1-2 yeats. The sex ratio was approximately 1:1 in the overall population. However, the larger crabs are predominantly male. The age distribution of S. yangtsekinese was estimated from size frequency histograms. There were more adult crabs  相似文献   

15.
Aquaculture production efficiency may increase by using feed additives. This study investigated the effects of different dietary additives [w/w: 2% small peptides, 0.01% probiotics( Bacillus licheniformis) and 0.2% prebiotics(inulin)] on growth performance, digestive enzyme activities, and oxidative stress in juvenile Epinephelus coioides reared in artificial seawater of two salt concentrations(13.5 vs. 28.5). Weight gain rate was significantly higher in fish fed the diet supplemented with small peptides, B. licheniformis, inulin, or synbiotics than that in fish fed the basal diet; the greatest weight gain rate was found in fish fed the small peptide treatment [56.0% higher than basal diet]. Higher feed efficiency was detected in fish fed the diet supplemented with small peptides than that of fish in the other dietary treatments. Total protease activity in the stomach and intestines was highest in fish fed the small peptide-treated diet, whereas lipase activity was highest in those fed synbiotics(combination of Bacillus licheniformis and inulin) than that in fish fed the other treatments. Antioxidant enzyme(total superoxide dismutase and catalase) activities and hepatic malondialdehyde content were higher in fish receiving the dietary supplements and maintained in artificial seawater containing 13.5 salinity compared with those in the control(28.5). Hepatic catalase activity in grouper fed the diets with small peptides or synbiotics decreased significantly compared with that in control fish. Overall, the three types of additives improved growth rate of juvenile grouper and digestive enzymes activities to varying degrees but did not effectively improve antioxidant capacity under low-salinity stress conditions.  相似文献   

16.
这里所指示的大气圈、水圈、岩石圈、生物圈以及人类的作用千变万化,从而对人类的生存造成巨大影响,构成了一个复杂的生态环境,讨论这些问题,对人类生存至关重要。  相似文献   

17.
Monthly investigations were mae on the population of Chinese freshwater crab,Sinopotamon yangtsekiense Bott, 1967 from April, 1984 to March, 1985. The data on 4413 specimens show that the growth was affected mainly by temperature. During the April to November growth period, the crabs' major development occurred from June through October. One year was required for a fine white oocyte to develop into a mature egg. The reproduction period was June–October. Females bearing eggs were taken from June–August, and crabs with young were found from July–October. The females reproduced once a year but could for more than one year. The number of eggs carried by a female varied greatly according to the size of the crab, ranging from 30 to 100 eggs. New-born crabs become mature after 1–2 years. The sex ratio was approximately 1∶1 in the overall population. However, the larger crabs are predominantly male. The age distribution ofS. yangtsekinese was estimated from size frequency histograms. There were more adult crabs (over 70%) from June to October and more immature crabs (over 50%) from November to May.  相似文献   

18.
Potassium, sodium, magnesium and iodine requirements of shrimp, Penaeus chinensis were studied.Orthogonal design was employed in this experiment. The composition of the basal diet consisted of fishmeal, peanut cake, corn meal, soybean cake, wheat bran, vitamin mix and mineral mix, and supple-mentations of potassium, sodium, magnesium and iodine in the basal diet were made according to theL_9(3~4) orthogonal table. The results indicatal that iodine supplementation improved growth of the shrimpsignificantly and raised survival very significanly, iodine requirement of the shrimp was 0.003%, sodiumrequirement was 0.87% or less; and that 1.1-1.3% potassium and 0.18-0.38% magnesium in the dietwere proper nutrition supplements for the shrimp.  相似文献   

19.
A study was conducted on Cu, Zn, Cd, Fe, Co and Ni levels in Saanich Inlet anoxic seawaler. Data on the concentrations of these trace metals and H2S, and other oceanographic parameters were obtained in four cruisesEquilibrium models are presented together with in situ data. The" results strongly support the assumption that the solubilities of Cu, Zn, Cd, Fe, Co and Ni are controlled by bisulfide and /or polysulfide complexes. The species of Cu, Zn, Cd and Ni are shown to be Cu(S4)23- and Cu(S4S5)3-, Zn(HS)20 and ZnHS2-, Cd(HS)20 and Ni(HS)20 respectively. The solid species controlling Fe2 + and Co2+ are respectively the pyrohotites FeS and CoS. The data illustrates that thermodynamic equilibrium has been established in the H2S-controlled seawater of Saanich Inlet, and that equilibrium has not been established in the H2S-O2-coexisted seawater of Saanich Inlet. The lack of equilibrium in the H2S-O2-coexisted seawater is a result of the flushing or mixing of oxygenated seawater with anoxic water. The new s  相似文献   

20.
Potassium, sodium, magnesium and iodine requirements of shrimp,Penaeus chinensis were studied. Orthogonal design was employed in this experiment. The composition of the basal diet consisted of fish meal, peanut cake, corn meal, soybean cake, wheat bran, vitamin mix and mineral mix, and supplementations of potassium, sodium, magnesium and iodine in the basal diet were made according to the L9(34) orthogonal table. The results indicated that iodine supplementation improved growth of the shrimp significantly and raised survival very significantly, iodine requirement of the shrimp was 0.003%; sodium requirement was 0.87% or less; and that 1.1–1.3% potassium and 0.18–0.38% magnesium in the diet were proper nutrition supplements for the shrimp. Contribution No. 2342 from the Institute of Oceanology, Chinese Academy of Sciences.  相似文献   

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