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动态监测血清降钙素原水平在ICU老年重症肺炎患者的临床意义 被引量:4
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作者 李忠河 《中国卫生产业》 2014年第28期158-159,共2页
目的探讨血清降钙素水平在ICU老年重症肺炎患者的临床意义。方法设立四个组别,重症肺部感染患者(重症组)49例,非重症肺部感染患者(非重症组)32例,除外感染性疾病的患者(非感染组)32例,体检健康者(健康组)32例,分别对于这些患者进行血清... 目的探讨血清降钙素水平在ICU老年重症肺炎患者的临床意义。方法设立四个组别,重症肺部感染患者(重症组)49例,非重症肺部感染患者(非重症组)32例,除外感染性疾病的患者(非感染组)32例,体检健康者(健康组)32例,分别对于这些患者进行血清降钙素原、白细胞计数、超敏C反应蛋白进行测定及比较分析。结果血清降钙素原在重症组与非重症组、非感染组、健康组之间的差异比较明显(P<0.05),具有统计学意义。结论血清降钙素原水平与肺炎患者的患病程度有关,通过对血清降钙素原实施动态监测,有利于我们观察老年肺部感染的程度,是我们预测和识别老年人重症肺部感染的辅助诊断指标。 展开更多
关键词 监测 血清降钙素 原水平 老年重症肺炎患者
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Analysis of the Groundwater System Change and Driving Factors in Songnen Plain in Jilin Province 被引量:1
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作者 郭晓东 张晶 +2 位作者 田辉 朱威 张梅桂 《Agricultural Science & Technology》 CAS 2011年第5期741-744,共4页
[Objective] The aim was to provide theoretical basis for the study of underground water dynamic changes in Songnen Plain in Jilin Province.[Method] The dynamic changes and driving factors for the underground water in ... [Objective] The aim was to provide theoretical basis for the study of underground water dynamic changes in Songnen Plain in Jilin Province.[Method] The dynamic changes and driving factors for the underground water in Songnen Plain in Jilin Province was expounded.[Result] Since 1960s,the temperature in the Songnen Plain in Jilin Province increased gradually.The average temperature increased 2℃;precipitation reduced gradually.Especially,the trend of precipitation reduction in west area was more distinct;in the meantime,the development of underground water augmented gradually and reached 2 800 million m3 in 2008.Driven by many factors,regional underground water level had distinct changes.Potential water position reduced greatly in northwest fan-shaped area.The one in other places were stable and even increased in certain parts;confined water position decreased quickly in general and it increased in certain parts.[Conclusion] The general deterioration trend of underground water environment was inevitable.But,the deterioration process can be eased through scientific planning and regional underground water resources so as to realize sustainable utilization of regional underground water resources. 展开更多
关键词 Songnen Plain Groundwater dynamic Drive factor
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Survey of breeding populations of the Red-Crowned Crane (Grus japonensis) in the Songnen Plain,northeastern China 被引量:2
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作者 钱法文 江红星 +4 位作者 于国海 于有忠 杨军 逄士良 朴仁珠 《Chinese Birds》 2012年第3期217-224,共8页
With the support of the UNEP/GEF Siberian Crane Wetland Project,a five-year field survey of breeding waterbirds was conducted in four nature reserves - Zhalong,Keerqin,Xianghai and Momoge National Nature Reserves in t... With the support of the UNEP/GEF Siberian Crane Wetland Project,a five-year field survey of breeding waterbirds was conducted in four nature reserves - Zhalong,Keerqin,Xianghai and Momoge National Nature Reserves in the Songnen Plain for the period from May 2004 to August 2008.The purpose of the survey was to improve our understanding of the distribution and populations of breeding waterbirds in this area.The Red-crowned Crane (Grus japonensis) was the most important target species.Our survey results confirm that the Zhalong wetland is the largest breeding ground for the Red-crowned cranes in the Songnen Plain.Over 90% of the breeding birds were found in Zhalong,with numbers fluctuating from 112 to 275 over the years.Reed (Phragmites australis) is the most important plant species associated with breeding locations of this bird species.Water supply to the wetland can relieve pressure from deterioration of wetland habitats for the breeding of Red-crowned cranes.However,a sound scientific basis for the water supply mechanism is the key to better management of their habitat and a prerequisite for ensuring the breeding success of the Red-crowned Crane. 展开更多
关键词 breeding location Songnen Plain Zhalong Phragmites australis water supply
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Soil Properties and Yield of Jerusalem Artichoke(Helianthus tuberosus L.)with Seawater Irrigation in North China Plain 被引量:9
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作者 ZHAO Geng-Mao LIU Zhao-Pu CHEN Ming-Da GUO Shi-Wei 《Pedosphere》 SCIE CAS CSCD 2008年第2期195-202,共8页
Irrigation with various dilutions of seawater can act as an alternate water resource and thus plays an important role in saving freshwater resources as well as promoting agriculture in the coastal semi-arid areas of t... Irrigation with various dilutions of seawater can act as an alternate water resource and thus plays an important role in saving freshwater resources as well as promoting agriculture in the coastal semi-arid areas of the North China Plain. Jerusalem artichoke (Helianthus tuberosus L.) grown in a field experiment was irrigated with seawater diluted with freshwater from 2001 to 2003 to determine the feasibility of seawater irrigation in the Laizhou area. For treatments of CK (non-irrigation) along with seawater concentrations of 25%, 50%, and 75%, total dissolved solid (TDS) in the non-irrigated soil significantly increased (P ≤ 0.05) in both 2002 and 2003 and was 1.3 times higher in 2003 than in 2001. In the 25% and 50% seawater concentration treatments, TDS in 2001 was significantly greater (P ≤ 0.05) than CK; however, TDS in these two treatments decreased by 34.9% and 40.1%, respectively, in 2003 compared with 2001. The sodium adsorption ratio (SAR) remained below 10 mmol^1/2 L^-1/2, indicating that alkalization was low with seawater irrigation. In 2001 and 2002, compared to CK and the irrigation treatment with 75% seawater, irrigation with 25% and 50% seawater increased the yields of Jerusalem .artichoke. This meant that Jerusalem artichoke could be safely grown in salt-affected land of Laizhou area with 25% and 50% seawater irrigation. 展开更多
关键词 Jerusalem artichoke North China Plain SAR seawater irrigation soil total dissolved solids
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Effect of lamivudinein in BeAg-positive chronic hepatitis B: Discordant effect on HBeAg and HBV DNA according to pretreatment ALT level 被引量:5
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作者 Tomoko Kurihara Fumio Imazeki +4 位作者 Osamu Yokosuka Kenichi Fukai Tatsuo Kanda Shigenobu Kawai Hiromitsu Saisho 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第22期3346-3350,共5页
AM: To clarify differences in antiviral effect of the drug in patients with different ALT levels, we examined the changes in HBV markers in patients with high or low ALT levels with or without lamivudine treatment. ME... AM: To clarify differences in antiviral effect of the drug in patients with different ALT levels, we examined the changes in HBV markers in patients with high or low ALT levels with or without lamivudine treatment. METHODS: Thirty-seven HBeAg-positive patients were studied. Ten patients with ALT levels higher than 200 IU/L (group 1) and 8 patients with ALT below 200 IU/L (group 2) were treated orally with 100 mg/d of lamivudine. As untreated control, 9 patients with ALT above 200 IU/L (group 3) and 10 patients with ALT below 200 IU/L (group 4) were examined. ALT level, HBeAg/HBeAb status, and HBV DNA level were examined monthly for 11.9±0.4 mo. RESULTS: The ALT level normalized in all 10 patients of group 1, 7/8 of group 2, 4/9 of group 3, and 1/10 of group 4 within 6 mo (groups 1 vs2, P= NS; groups 1 vs 3, P= 0.002; groups 1 vs4, P<0.0001). HBV DNA fell below the detection limit in all 10 patients of group 1, 7/8 of group 2, 0/9 of group 3, and 0/10 of group 4 within 6 mo (groups 1 vs 2, P - NS). HBeAg became seronegative in 7/10 patients of group 1, 1/8 of group 2, 3/9 of group 3, and 0/10 of group 4 within 12 mo (groups 1 vs2, P= 0.02; groups 1 vs 3, P= NS). CONCLUSION: Our data suggest that HBeAg-positive patients with higher ALT levels can be considered good candidates for lamivudine therapy, probably because lamivudine accelerates the natural seroconversion of HBeAg, accompanied by HBV DNA loss, in these patients. 展开更多
关键词 LAMIVUDINE Chronic hepatitis B HBEAG HBV DNA ALT
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Shallow groundwater dynamics in North China Plain 被引量:5
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作者 王仕琴 宋献方 +3 位作者 王勤学 肖国强 刘昌明 柳鉴容 《Journal of Geographical Sciences》 SCIE CSCD 2009年第2期175-188,共14页
The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North China Plain(NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU... The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North China Plain(NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU II of Japan.The automatic groundwater sensors were installed for the corporation project between China and Japan.Combined with the monitoring results from 2004 to 2006 with the major factors affecting the dynamic patterns of groundwater, such as topography and landform, depth of groundwater level, exploitation or discharge extent, rivers and lakes, the dynamic regions of NCP groundwater were gotten.According to the dynamic features of groundwater in NCP, six dynamic patterns of groundwater level were identified, including discharge pattern in the piedmont plain, lateral recharge-runoff-discharge pattern in the piedmont plain, recharge-discharge pattern in the central channel zone, precipitation infiltration-evaporation pattern in the shallow groundwater region of the central plain, lateral recharge-evaporation pattern in the recharge-affected area along the Yellow River and infiltration-discharge-evaporation pattern in the littoral plain.Based on this, the groundwater fluctuation features of various dynamic patterns were interpreted and the influencing factors of different dynamic patterns were compared. 展开更多
关键词 North China Plain shallow groundwater dynamic region dynamic feature of groundwater
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Unexplained liver laceration after metastasis radiofrequency ablation 被引量:3
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作者 Esther Ua Javier Trueba Jose Manuel Montes 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第40期5103-5105,共3页
Many studies have established the role of radiofrequency (RF) ablation as a minimally invasive treatment for liver metastases. Although relatively safe, several complications have been reported with the increased use ... Many studies have established the role of radiofrequency (RF) ablation as a minimally invasive treatment for liver metastases. Although relatively safe, several complications have been reported with the increased use of RF ablation. We describe here a case of unexplained liver laceration after a RF procedure. A woman who presented a solitary metachronous liver metastasis underwent RF ablation treatment for this lesion. Six hours later the patient displayed fatigue and pallor. Emergency blood tests showed a haemoglobin level of < 7 g/dL and markedly elevated transaminase levels. A computed tomography examination revealed two areas of liver laceration with haematoma, one of them following the path of the needle and the other leading away from the f irst. Following a blood transfusion, the patient was haemodynamically stable and completely recovered 24 h later. The patient remained in bed for 1 wk. No surgical intervention was required, and she was discharged 1 wk later. 展开更多
关键词 Colon cancer Liver haemorrhage Liver laceration Liver metastases Radiofrequency ablation
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High Accuracy Calculation for Excited-State Energies of H Atoms in a Magnetic Field 被引量:3
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作者 ZHAO Li-Bo DU Meng-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第8期339-345,共7页
Using the recently developed finite-basis-set method with B splines, excited states of H atoms in a magnetic field have been calculated. Energy levels are presented for the ten excited states, 2so, 3d'0, 3po, 3p-1, 3... Using the recently developed finite-basis-set method with B splines, excited states of H atoms in a magnetic field have been calculated. Energy levels are presented for the ten excited states, 2so, 3d'0, 3po, 3p-1, 3d_1, 4d-1, 3d-2, 4d-2, 4f-2 , and 5f-2 as a function of magnetic field strengths with a range from zero up to 2.35 × 10^6 T. The obtained results are compared with available high accuracy theoretical data reported in the literature and found to be in excellent agreement. The comparison also shows that the current method can produce energy levels with an accuracy higher than the existing high accuracy method [Phys. Rev. A 54 (1996) 287]. Here high accuracy energy levels are for the first time reported for the 3d'0, 4d-1, 4d-2, 4f-2, and 5f-2 states. 展开更多
关键词 H atoms strong magnetic fields white dwarf stars
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Fruit shape detection by level set 被引量:2
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作者 GUI Jiang-sheng RAO Xiu-qin YING Yi-bin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第8期1232-1236,共5页
A novel approach for fruit shape detection in RGB space was proposed,which was based on fast level set and Chan-Vese model named as Modified Chan-Vese model(MCV) . This new algorithm is fast and suitable for fruit sor... A novel approach for fruit shape detection in RGB space was proposed,which was based on fast level set and Chan-Vese model named as Modified Chan-Vese model(MCV) . This new algorithm is fast and suitable for fruit sorting because it does not need re-initializing. MCV has three advantages compared to the traditional methods. First,it provides a unified frame-work for detecting fruit shape boundary,and does not need any preprocessing even though the raw image is noisy or blurred. Second,if the fruit has different colors at the edges,it can detect perfect boundary. Third,it processed directly in color space without any transformations that may lose much information. The proposed method has been applied to fruit shape detection with promising result. 展开更多
关键词 Machine vision Shape detection Level set Fruit sorting
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Groundwater Contamination with NO_3-N in a Wheat-Corn Cropping System in the North China Plain 被引量:20
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作者 ZHAO Bing-Zi ZHANG Jia-Bao +3 位作者 M. FLURY ZHU An-Ning JIANG Qi-Ao BI Jin-Wei 《Pedosphere》 SCIE CAS CSCD 2007年第6期721-731,共11页
The North China Plain,where summer corn(Zea mays L.)and winter wheat(Triticum aestivum L.)are the major crops grown,is a major agricultural area in China.Permeable soils make the region susceptible to groundwater poll... The North China Plain,where summer corn(Zea mays L.)and winter wheat(Triticum aestivum L.)are the major crops grown,is a major agricultural area in China.Permeable soils make the region susceptible to groundwater pollution by NO_3-N,which is applied to fields in large amounts of more than 400 kg NO_3-N ha^(-1)as fertilizer.A field experiment was established in 2002 to examine the relationship among N fertilization rate,soil NO_3-N,and NO_3-N groundwater contamination.Two adjacent fields were fertilized with local farmers' N fertilization rate(LN)and double the normal application rate(HN),respectively,and managed under otherwise identical conditions.The fields were under a traditional summer corn/winter wheat rotation.Over a 22-month period,we monitored NO_3-N concentrations in both bulk soil and soil pore water in 20-40 cm increments up to 180 cm depth.We also monitored NO_3-N concentrations in groundwater and the depth of the groundwater table.No significant differences in soil NO_3-N were observed between the LN and HN treatment.We identified NO_3-N plumes moving downward through the soil profile.The HN treatment resulted in significantly higher groundwater NO_3-N,relative to the LN treatment,with groundwater NO_3-N consistently exceeding the maximum safe level of 10 mg L^(-1),but groundwater NO_3-N above the maximum safe level was also observed in the LN treatment after heavy rain.Heavy rain in June,July,and August 2003 caused increased NO_3-N leaching through the soil and elevated NO_3-N concentrations in the groundwater.Concurrent rise of the groundwater table into NO_3-N- rich soil layers also contributed to the increased NO_3-N concentrations in the groundwater.Our results indicate that under conditions of average rainfall,soil NO_3-N was accumulated in the soil profile.The subsequent significantly higher- than-average rainfalls continuously flushed the soil NO_3-N into deeper layers and raised the groundwater table,which caused continuous groundwater contamination with NO_3-N.The results suggest that under common farming practices in the North China Plain,groundwater contamination with NO_3-N was likely,especially during heavy rainfalls,and the degree of groundwater contamination appeared to be proportional to the N application rates.Decreasing fertilization rates, splitting fertilizer inputs,and optimizing irrigation scheduling had potential to reduce groundwater NO_3-N contamination. 展开更多
关键词 field experiment groundwater contamination NO3-N wheat-corn cropping system
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Water Resource Management in the Intermountain Izeh Plain,Southwest of Iran 被引量:1
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作者 Kalantari.N Pawar.N.J Keshavarzi.M.R 《Journal of Mountain Science》 SCIE CSCD 2009年第1期25-41,共17页
Ever growing demand for water for agricultural activities in the Izeh Plain has enhanced the use of groundwater. Due to enormous groundwater abstraction since 1985, the overall static water level has receded by more t... Ever growing demand for water for agricultural activities in the Izeh Plain has enhanced the use of groundwater. Due to enormous groundwater abstraction since 1985, the overall static water level has receded by more than 5 meters reflecting that the aquifer is under stress condition. As a result, interest is focused on application of artificial recharge as an option for groundwater management to augment water supply in this area. Therefore, in the present investigations, suitable sites for artificial recharge were selected by an integrated surface and sub-surface assessment of the area. On the basis of the data collected from four target points, it was realized that the selected sites for artificial recharge could not meet water demand of the area. In this study attention was also paid to utilization of the existing Miangran Lake water as an alternative to combat water shortage for irrigation. The study further indicated that the available Miangran Lake water could be used for irrigation of the reclaimed agricultural land and enabling to convert 20o0 hectares of rain-fed land into irrigation. The total cost to utilize lake water is US$ 2,756,729 and it was estimated that the project could recoup the investment within 5 years which is quite reasonable in this water scarcity prone area. 展开更多
关键词 Artificial recharge STREAM MiangranLake GROUNDWATER Izeh Plain
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Fuzzy Synthetic Evaluation of Water Quality of Naoli River Using Parameter Correlation Analysis 被引量:14
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作者 WANG Jianhua LU Xianguo +1 位作者 TIAN Jinghan JIANG Ming 《Chinese Geographical Science》 SCIE CSCD 2008年第4期361-368,共8页
In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang ... In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang Plain, Northeast China. The basic principle of the PCA is that the pairs of parameters which are highly correlated and linear with each other would contribute the same information to an assessment and one of them should be eliminated. The method of the PCA is that a correlation relationship among candidate parameters is examined before the FSE. If there is an apparent nonlinear or curvilinear relationship between two parameters, then both will be retained; if the correlation is significant (p<0.01), and the scatter plot suggests a linear relationship, then one of them will be deleted. However, which one will be deleted? For solving this problem, a sensitivity test was conducted and the higher sensitivity parameters remained. The results indicate that the original data should be preprocessed through the PCA for redundancy and variability. The study shows that introducing the PCA into the FSE can simplify the FSE calculation process greatly, while the results have not been changed much. 展开更多
关键词 Parameter Correlation Analysis (PCA) Fuzzy Synthetic Evaluation (FSE) surface water quality Naoli River Sanjiang Plain
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Evaluation of nitrate source in groundwater of southern part of North China Plain based on multi-isotope 被引量:1
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作者 方晶晶 周爱国 +4 位作者 马传明 刘存富 蔡鹤生 甘义群 刘运德 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期610-618,共9页
Nitrate pollution in groundwater is a serious water quality problem that increases the risk of developing various cancers.Groundwater is the most important water resource and supports a population of 5 million in Anya... Nitrate pollution in groundwater is a serious water quality problem that increases the risk of developing various cancers.Groundwater is the most important water resource and supports a population of 5 million in Anyang area of the southern part of the North China Plain. Determining the source of nitrate pollution is the challenge in hydrology area due to the complex processes of migration and transformation. A new method is presented to determine the source of nitrogen pollution by combining the composition characteristics of stable carbon isotope in dissolved organic carbon in groundwater. The source of groundwater nitrate is dominated by agricultural fertilizers, as well as manure and wastewater. Mineralization, nitrification and mixing processes occur in the groundwater recharge area, whereas the confined groundwater area is dominated by denitrification processes. 展开更多
关键词 δ^12NNO3 δ^18ONO3 δ^13CDOC esophageal cancer GROUNDWATER
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Subluminal and Superluminal Phenomena in a Four-Level Atom 被引量:1
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作者 HAN Ding-An ZENG Ya-Guang CAO Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期197-200,共4页
In a four-level atomic system, we investigate the light pulse propagation properties interacting with only one laser field. It is shown that in the steady state, the group velocity of the light pulse can be changed fr... In a four-level atomic system, we investigate the light pulse propagation properties interacting with only one laser field. It is shown that in the steady state, the group velocity of the light pulse can be changed from subluminal to superluminal by varying the field detuning. Meanwhile, the effects of the field intensity on the group velocity are also shown. At last, with special parameters, the analytical solution for the group index is also obtained. 展开更多
关键词 SUPERLUMINAL SUBLUMINAL
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Could It Happen: Global Warming Leads to the Extinction of Mankind? 被引量:1
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作者 Jan-Erik Lane 《Management Studies》 2017年第6期545-554,共10页
The upcoming COP23 at Bonn of the UN and its UNFCCC must outline how its COP21 objectives are to be promoted by means of concrete international and national management. Only a massive replacement of fossil fuels and w... The upcoming COP23 at Bonn of the UN and its UNFCCC must outline how its COP21 objectives are to be promoted by means of concrete international and national management. Only a massive replacement of fossil fuels and wood coal by solar power parks, can wind power and atomic power save mankind from the grave threats of global warming. This paper presents a tentative estimation of what is involved with regard to the fulfilment of COP21 's GOAL II--decarbonisation to 30-40 per cent of 2005 level of emissions. 展开更多
关键词 decarbonisation the UNFCCC's COP21 Goals I II LII implementation gap game strategies commonpool regime (CPR) defection
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Some Problems of Irrigation Water Management in Lower Cheliff Plain (Algeria) 被引量:1
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作者 Abdelhamid BradaI Abdelkader Douaoui Tarik Hartani 《Journal of Environmental Science and Engineering(A)》 2012年第3期271-278,共8页
In the Lower Cheliff Plain (northwestern of Algeria), the waters resources are limited; the adoption of a rational approach in the management of irrigation water in the irrigated perimeter poses an inequality in the... In the Lower Cheliff Plain (northwestern of Algeria), the waters resources are limited; the adoption of a rational approach in the management of irrigation water in the irrigated perimeter poses an inequality in the balance between supply and demand. The two surface water resources, Gargar and Merdjet Sidi Abed dams, do not satisfy the requirements of agriculture water. According to the National Office of the Irrigation and Drainage data, the quantity of allocated water is never distributed; the difference between allocated water and drop water can also exceed 20%, and then, another problem of management is that the water losses in the distribution can reach 20% again. The shortage irrigation water resource allocated has constrained the farmers to use groundwater. The chemical analysis of 56 simples to this water showed a significant chemical diversity in the compositions. There is a high salinity risk (C3 class) or very high risk (C4 class) of soil salinisation. A space chart distribution to the EC water probability to exceed 2.25 dS/m interpolated by the indicator kriging method showed that 78% of the groundwater surface presents a significant probability to exceed this limit. The average value of the SAR (sodium adsorption ratio) is lower than 10 that indicates a moderate risk of sodisation. This observation is in contradiction with the high values of the SAR measured in the soil solution. The approach of residual alkalinity (RSC) shows that a good number of drillings analyzed presents a positive sign RSC (RSC 〉 0). This water presents a real danger of sodisation. They have a low salinity, which, for a farmer, does not present any danger. 展开更多
关键词 Management water irrigation GROUNDWATER water quality.
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Response of Regeneration Diversity of Carex Lasiocarpa Community to Different Water Levels in Sanjiang Plain,China 被引量:5
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作者 WANG Li SONG Changchun +1 位作者 HU Jinmin YANG Tao 《Chinese Geographical Science》 SCIE CSCD 2010年第1期37-42,共6页
The species diversity at the regeneration stage, inflenced by different water levels, is important for community composition in the later growing season.Regeneration diversity of Carex lasiocarpa community under diffe... The species diversity at the regeneration stage, inflenced by different water levels, is important for community composition in the later growing season.Regeneration diversity of Carex lasiocarpa community under different water levels was studied at two stages, recruitment and adult, in the Sanjiang Plain, Heilongjiang Province, China.The results showed that, at the two growing stages, important value of C.lasiocarpa population and species richness of the community decreased with the increasing water level, while the Simpson and Shannon-Wiener diversity indexes and Pielou evenness index increased.Under different water levels, community diversities were higher at the recruitment stage, while population important values of C.lasiocarpa were higher at the adult stage.Indexes in vegetation evaluation must be chosen prudentially for successful restoration and effective management of wetlands, and especially for wetland restoration, the optimal time should be selected according to the restoration objectives and costs. 展开更多
关键词 water level population dominance species diversity marsh wetland Sanjiang Plain
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Change of ancient hydrology net in Northeast China Plain
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作者 Hui QU Yu CHU +2 位作者 Fenglong ZHANG Full QI Xiangkui YANG 《Global Geology》 2006年第2期253-257,共5页
Comparing with lithofacies palaeogeography of several great plains,the authors analyzed four great plains in Quaternary diastrophism,the sedimentary facies,sedimentary environment and their evolution from the independ... Comparing with lithofacies palaeogeography of several great plains,the authors analyzed four great plains in Quaternary diastrophism,the sedimentary facies,sedimentary environment and their evolution from the independent embryonic and river system of ancient Heilongjiang finally to the Halar highland,Songnen Plain,Sanjiang Plain,the Xingkai Lake Plain and various river systems,collected the unification outside the system of Heilongjiang River to release into the sea,south ancient Xialiao River finally piracy Dongliao River,Xialiao River had released into the sea the ancient water law vicissitude and the evolved rule. 展开更多
关键词 Northeast Plain ancient hydrology net CHANGE
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Assessment of Groundwater Pollution Potential through GIS Technique: A Case Study for Pelly-Mianrudan Plain, Lali Urban District, Iran 被引量:1
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作者 M. Chitsazan Z. Rahimi Y. Mirzaee 《Journal of Environmental Science and Engineering》 2011年第10期1350-1362,共13页
Considering the low average rainfall in the country and the importance of groundwater as a water supply source for drinking and agricultural water sections, water quality condition of groundwater must be controlled an... Considering the low average rainfall in the country and the importance of groundwater as a water supply source for drinking and agricultural water sections, water quality condition of groundwater must be controlled and prevented from any contamination. Identifying the vulnerable areas to pollution is one way of prevention. Many models have been offered for this purpose. In this study, a numerical rating scheme, called DRASTIC has been used for evaluating potential for groundwater pollution in pelly-mianrudan plain that is located in northern Lalli city in Khuzestan province. Resulted map obtained in GIS environment shows that the study area has DRASTIC index of 71-150 that is divided to five vulnerable zones namely no significance, very low, low, low to moderate, moderate to high. Maximum groundwater vulnerability correspondent low to medium zone that approximately covers 45 percentage of the study area and other parts on the northwest and center of the study area has high vulnerability. The sensitivity analysis showed that correlation DRASTIC index with net Recharge (0.68) and Impact of vadose zone media (0.63) parameters is more than other parameters in the study pelly-mianrudan area. The statistical analysis confirms that parameter soil media and topography are the most sensitive to contamination, followed in importance by parameters aquifer medium, vadose zone, recharge, hydraulic conductivity and depth to water. 展开更多
关键词 Aquifer vulnerability DRASTIC model geographical information system pelly-mianrudan plain sensitivity analysis.
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New Levels of the Pr Atom with Almost Similar Energies
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作者 Zaheer Uddin Imran Siddiqui +3 位作者 Shamim Khan B. Gamper Esam H.Abdul-Hafidh L. Windholz 《Journal of Physical Science and Application》 2012年第4期88-94,共7页
A Fourier transform (FT) spectrum of praseodymium (Pr) extending from UV to IR was investigated. Hyperfine (hf) structures of unclassified lines with sufficiently high signal to noise ratio (SNR) were analyzed... A Fourier transform (FT) spectrum of praseodymium (Pr) extending from UV to IR was investigated. Hyperfine (hf) structures of unclassified lines with sufficiently high signal to noise ratio (SNR) were analyzed and some new levels were found. We present these new levels in this work. Some of the new levels have energies almost equal to the energies of already known or other new levels, distinguished either by different values of angular momentum J or by their parity. 展开更多
关键词 Hyperfine structure PRASEODYMIUM fourier spectrum.
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