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Features and factors of radium isotopes in Tianjin’s typical estuaries
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作者 Zhe Zhang Yingchun Dong +3 位作者 Lixin Yi Xin Hao Yajie Zheng Tianxue Lü 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期134-146,共13页
In order to characterize the features of radium isotopes in estuaries of Tianjin,a continuous survey and sampling of typical estuaries were conducted from 2013 to 2017 in this study.The activities of natural radioacti... In order to characterize the features of radium isotopes in estuaries of Tianjin,a continuous survey and sampling of typical estuaries were conducted from 2013 to 2017 in this study.The activities of natural radioactive radium isotopes(^(223)Ra,^(224)Ra,and ^(228)Ra)in groundwater and surface water were measured by the radium-delayed coincidence counting(RaDeCC)system.The non-conservative behavior of the radium isotopes was investigated under hydrogeochemical conditions and urbanization.The results indicated that in terms of horizontal distribution,the activities of radium in groundwater(Hangu,Tanggu,and Dagang)showed an upward trend from north to south and demonstrated a higher figure than surface water(Haihe River and Duliujian River).Concerning the vertical distribution,the activitives of radium at a 15 m burial depth was higher than that at a 30 m burial depth in all measurements.The activities of radium isotopes in the study area increased with the increase of total dissolved solids,and their desorption behavior on Fe-Mn oxides was constrained by the redox intensity.Different hydrogeological conditions resulted in variations in the vertical profile of radium activities.The activity of radium was regulated by seasonal variation and precipitation in groundwater and surface water.In addition,the rapid urbanization has caused a significant impact on the features of radium isotopes in typical estuaries of Tianjin.Meanwhile,radium isotopes can be applied to reflect the impact of urbanization on surface watergroundwater systems.Clarifying and cleverly utilizing the relationship between behavior of radium isotopes and urbanization will promote the development of the Tianjin Binhai New Area in a healthy way. 展开更多
关键词 ESTUARY radium isotope total dissolved solids ionic strength URBANIZATION
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Simulation of transport mechanism of radium isotopes in aquifer on the southern coast of Laizhou Bay
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作者 Yancheng Wang Guangquan Chen +7 位作者 Hongjun Yu Xingyong Xu Yinqiao Zou Wenqing Zhao Weitao Han Wenzhe Lyu Zhen Cui Runtian Ding 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期40-48,共9页
Naturally occurring radium(^(223)Ra,^(224)Ra,^(226)Ra,and^(228)Ra)isotopes have been widely applied as geochemical tracers in marine environments,especially when estimating the submarine groundwater discharge(SGD).In ... Naturally occurring radium(^(223)Ra,^(224)Ra,^(226)Ra,and^(228)Ra)isotopes have been widely applied as geochemical tracers in marine environments,especially when estimating the submarine groundwater discharge(SGD).In this sense,the influencing factors and transport mechanism of radium isotope activity in aquifers can be key information for SGD estimation.This work evaluates the adsorption/desorption behavior of^(224)Ra and^(226)Ra in the solid-liquid phase through a leaching experiment and analysis of field data.The results suggested that radium isotope activity was positively correlated with salinity and grain size,in the case of abundant sediments.Through ion analysis,we found that the ions(Na^(+),Ca^(2+),Mg^(2+),and Ba^(2+))exchanged with radium isotopes in the process of transport.A 1-D reactive transport model was established to simulate the transport process of radium isotope in aquifers.The model successfully simulated the variation of radium isotope desorption activity with salinity and was subsequently verified in the field.This study contributes to the understanding of the geochemical behavior of radium isotopes in aquifers and provides guidance for selecting a suitable groundwater endmember in SGD estimation. 展开更多
关键词 radium adsorption/desorption behavior leaching experiment reactive transport model coastal aquifer Laizhou Bay
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Using radium isotopes to evaluate the uncertainty of submarine groundwater discharge in the northeast and entirety of Daya Bay
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作者 Hequan Gu Feng Zhao +6 位作者 Zhixin Ni Meigui Wu Li Zhao Aicui Dang Dongmei Li Minxia Zhang Qin Hu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期24-31,共8页
Submarine groundwater discharge(SGD),which can be traced using naturally occurring radium isotopes,has been recognized as a significant nutrient source and land-ocean interaction passage for the coastal waters of the ... Submarine groundwater discharge(SGD),which can be traced using naturally occurring radium isotopes,has been recognized as a significant nutrient source and land-ocean interaction passage for the coastal waters of the Daya Bay,China.However,uncertainties in assessing SGD fluxes must still be discussed in detail.In this study,we attempted to utilize the Monte Carlo method to evaluate the uncertainties of radium-derived SGD flux in the northeast and entirety of the Daya Bay.The results show that the uncertainties of the SGD estimate in the northeast bay are very sensitive to variations in excess radium inventories as well as radium inputs from bottom sediments,while the uncertainties of the SGD estimate for the entire bay are strongly affected by fluctuations in radium inputs from bottom sediments and radium end-members of SGD.This study will help to distinguish the key factors controlling the accuracy of SGD estimates in similar coastal waters. 展开更多
关键词 submarine groundwater discharge(SGD) radium isotopes Monte-Carlo method Daya Bay uncertainty analysis
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Distinguishing the main components of submarine groundwater and estimating the corresponding fluxes based on radium tracing method—taking the Maowei Sea for example
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作者 Linwei Li Jinzhou Du +1 位作者 Xilong Wang Yanling Lao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期1-23,共23页
Submarine groundwater discharge(SGD)is an important part in the land-sea interactions,which mainly contains three components:submarine fresh groundwater discharge(SFGD),tidal flat recirculated saline groundwater disch... Submarine groundwater discharge(SGD)is an important part in the land-sea interactions,which mainly contains three components:submarine fresh groundwater discharge(SFGD),tidal flat recirculated saline groundwater discharge(tidal flat RSGD)and subtidal recirculated saline groundwater discharge(subtidal RSGD).In order to make a more accurate assessment of the impact of SGD on coastal ecological environment,it is necessary to distinguish the main components of SGD.In this study,the Maowei Sea,located in the northern part of the Beibu Gulf,was selected as the study area.Based on the radium(Ra)tracing method,we present a new analytical method for distinguishing the three main components of SGD in this area combined with field data.The average daily flow along the coastline of the Maowei Sea of tidal flat RSGD was slightly higher than that of SFGD,and both two were on the magnitude of 1×10^(5)m^(3)/d.The average daily flow for the subtidal RSGD of the entire subtidal zone of the Maowei Sea reached to the magnitude of 1×10^(6)-1×10^(7)m^(3)/d.The long-term variation trend of terrestrial SGD is a valuable information for the study of the influence of terrigenous material on the coastal ecological environment.Based on the results of four sampling periods,it is found that the fluxes of SFGD and tidal flat RSGD in the Maowei Sea had good linear correlation with the net precipitation.As an example,January 2015 to August 2022 were selected as the study periods,and the variation trends of SFGD and tidal flat RSGD were calculated by linear function with net precipitation as the independent variable.The results showed that the flux of tidal flat RSGD was slightly higher than that of SFGD,and the difference between the two is larger in flood season while smaller in dry season.In general,in the coastal range of China,the total SGD flux in the Maowei Sea area is at a high level,and the SFGD flux is at a medium level. 展开更多
关键词 submarine groundwater discharge bottom sediment radium tracing method offshore transport long-term monitoring
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Using radium isotopes to quantify submarine groundwater discharge at different scales in the Huanghe River Estuary,China
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作者 Haowei Xu Disong Yang +6 位作者 Xiaoyi Guo Maosheng Gao Guangquan Chen Diansheng Ji Shengtao Chen Huaming Yu Bochao Xu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期32-39,共8页
As an important land-ocean interaction process,submarine groundwater discharge(SGD)is composed of multiple dynamical processes at different scales and plays an important role in the study of coastal ocean geochemical ... As an important land-ocean interaction process,submarine groundwater discharge(SGD)is composed of multiple dynamical processes at different scales and plays an important role in the study of coastal ocean geochemical budgets.However,most of the existing studies focus on the quantification of the total groundwater discharge,few studies are about the differentiation and quantification of groundwater discharge processes at different scales(i.e.,short-scale SGD and long-scale SGD).As a world-class river,the Huanghe River is highly turbid and heavily regulated by humans.These natural and anthropogenic factors have a significant impact on groundwater discharge processes in the Huanghe River Estuary(HRE).In this study,the distribution patterns of the natural geochemical tracer radium isotopes(^(224)Ra and^(223)Ra)and other hydrological parameters in the HRE were investigated during four cruises.By solving the mass balance of^(224)Ra and^(223)Ra in the HRE,the long-scale SGD flux was quantified as 0.01−0.19 m/d,and the short-scale SGD flux was 0.03−0.04 m/d.The rate of short-scale SGD remained essentially constant among seasons,while the rate of long-scale SGD varied considerably at different periods and showed a synchronous trend with the variation of river discharge.The results of this study are significant for understanding the SGD dynamics in the HRE and the contribution of SGD to the ocean geochemical budgets. 展开更多
关键词 radium isotopes submarine groundwater discharge Huanghe River Estuary
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Optimization of enrichment and pretreatment of low-activity radium isotopes in the open ocean
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作者 Guiyuan Dai Guizhi Wang +2 位作者 Qing Li Weizhen Jiang Fei Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期171-177,共7页
In the open ocean,radium isotopes are useful tracers of residence time and water-mass mixing.However,limited by the measurement resolution of commonly used gamma counters,the low activity of radium in the open ocean m... In the open ocean,radium isotopes are useful tracers of residence time and water-mass mixing.However,limited by the measurement resolution of commonly used gamma counters,the low activity of radium in the open ocean makes it necessary to enrich radium from large volumes of seawater and pretreat radium-enriched carriers prior to measurements.The commonly applied method of radium enrichment and pretreatment,however,has limitations of uneven coating of MnO_(2)on cartridges,relatively expensive cartridges,time-consuming issues during cartridge-ashing,ash loss during transfer,and changes of gamma counters efficiency caused by different ash weights.To address these issues,in this study we optimized the enrichment and pretreatment of low-activity radium prior to measurements.Firstly,we replaced commonly used acrylic cartridges with cheaper polypropylene cartridges,which took 6 h to be ashed,42 h shorter than for acrylic cartridges.Secondly,MnO_(2)-coated cartridges were prepared with a circulating hot acidic KMnO_(4)solution to ensure homogeneous coating.The radium extraction efficiency of this MnO_(2)-coated cartridge was 20%-61%higher than that prepared by directly immersing cartridges in the solution.The radium delayed coincidence counter efficiency for MnO_(2)-coated cartridge was stable with a moisture content of 0.05-1.Lastly,after ashing cartridges,instead of directly transferring the ash to a measurement vial,a mixture of hydroxylamine hydrochloride and hydrochloric acid was used to completely leach the ash for long-lived radium,followed by coprecipitation by BaSO_(4),to avoid potential loss of ash during transfer and variations in measurement geometry due to different ash weights.And the recovery of long-lived radium pretreatment was 94%-102%,which improved by 11%compared with the common method.In addition,the radium extraction efficiency of the MnO_(2)-coated cartridge varied from 3%to 4%within the in situ pump working flow rate of 4-7 L/min,which fell within the measurement errors. 展开更多
关键词 radium isotopes MnO_(2)-coated cartridge enrichment of Ra pretreatment of MnO_(2)-coated cartridges RaDeCC efficiency extraction efficiency
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Prostate Cancer, Castration-Resistant Prostate Cancer (CRPC), Radium-223 Dichloride Injection for Bone Metastasized Prostate Cancer
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作者 Chamini Kumari Hemathilaka Wijelath Achchillage Chuanchuan Ren 《Journal of Cancer Therapy》 2023年第11期429-442,共14页
Purpose: The purpose of this paper is to discuss the most important facts about prostate cancer, its treatments and efficacy, the type of prostate cancer that does not improve with hormonal therapy (Castration-Resista... Purpose: The purpose of this paper is to discuss the most important facts about prostate cancer, its treatments and efficacy, the type of prostate cancer that does not improve with hormonal therapy (Castration-Resistant Prostate Cancer-CRPC), and the recently approved Radium-223 dichloride targeted therapy for CRPC that has metastasized to bones. Prostate cancer is the third most common malignancy diagnosed worldwide and the most common malignant disease in men. Also, the incidence of prostate cancer varies between regions. So it’s important to have a proper understanding of all above points to prevent the further development and spread of cancer and improve the cure rate. Design: The paper begins by discussing what prostate cancer is, the risk factors, clinical manifestations, and the treatments for prostate cancer. It covers the clinical manifestations, pathology, screening (cancer biomarker Prostate Specific Antigen, Digital Rectal Examination—DRE, prostate biopsy, and imaging) and treatments for prostate cancer. The paper then delves into the main treatment methods for prostate cancer, including how Castration-Resistant Prostate Cancer (CRPC) differs from normal prostate cancer after hormone suppression therapy. Additionally, it discusses the effectiveness of the recently introduced Radium-223 dichloride injection as a radiation-targeted therapy for treating CRPC that has metastasized to bones. This section covers the properties of radium-223 dichloride injection, its pharmacokinetics, pharmacodynamics, absorption and volume of distribution, half-life, metabolism, route of elimination, clearance, toxicity, adverse effects, and mechanism of action at the tumor site. It also discusses preclinical studies related to radium-223 dichloride injection and its effectiveness in treating CRPC patients with bone metastasis. Conclusion: Prostate cancer is a common cancer that can be treated with surgery or hormonal therapy. However, if the cancer progresses despite hormonal therapy, Radium-223 dichloride injection can be used as a radiation target therapy to treat patients with CRPC and symptomatic bone metastases. This treatment kills tumor cells in bones and reduces associated pain with minimal damage to surrounding normal tissue. However, the metastatic disease cannot be cured and can only offer palliation for the patient. Suggestions: Based on the facts, Radium-223 target therapy is effective in treating and providing palliation for cancers. It is suggested to further develop the usage of radiation target therapy and to test the safety and efficacy of more than 6 injections of Radium-223 dichloride and its combination with currently used chemotherapy drugs for bone metastasized CRPC. This paper aims to contribute to future research designs related to cancer therapies using radiation and to design new studies and practical implementations, especially regarding the usage of radium-223 dichloride. 展开更多
关键词 Prostate Cancer Castration-Resistant Prostate Cancer radium-223 Dichloride
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Quantification of submarine groundwater discharge(SGD) using radon,radium tracers and nutrient inputs in Punnakayal, south coast of India 被引量:3
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作者 S.Selvam P.Muthukumar +5 位作者 Sruthy Sajeev S.Venkatramanan S.Y.Chung K.Brindha D.S.Suresh Babu R.Murugan 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第1期29-38,共10页
The present study focused on the estimation of submarine groundwater discharge(SGD)and the effects of nutrient fluxes due to the SGD process.The parameters of SGD such as magnitude,character,and nutrient flux in Punna... The present study focused on the estimation of submarine groundwater discharge(SGD)and the effects of nutrient fluxes due to the SGD process.The parameters of SGD such as magnitude,character,and nutrient flux in Punnakayal region of South East coast of India were evaluated using multiple tracers of groundwater inputs in 2019.It was found that the elevated values for the tracers in the study area,displayed a gradational change in the values as move from estuarine part to the offshore.Simultaneous occurrence of fresh and saline SGD is observed on the study sites.Also,indicated that the SGD fluxes ranged from 0.04 to 0.12 m^3 m^-2d^-1 at the estuary and0.03-0.15 m^3 m^-2d^-1at the groundwater site.A substantially increased value for 222 Rn activities is distinguished in the estuary to values over 312 dpm L^-1.Nutrient embellishments were generally greatest at locations with substantial meteoric elements in groundwater;however,the recirculation of saltwater through the geological formation could provide a way of transferring terrestrially-derived nutrients to the coastal zone at many places. 展开更多
关键词 SGD RADON radium NUTRIENTS Coastal zone Box model
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Estimating submarine groundwater discharge and associated nutrient inputs into Daya Bay during spring using radium isotopes 被引量:1
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作者 Jing-yan Gao Xue-jing Wang +1 位作者 Yan Zhang Hai-long Li 《Water Science and Engineering》 EI CAS CSCD 2018年第2期120-130,共11页
Daya Bay, a semi-enclosed bay in the South China Sea, is well known for its aquaculture, agriculture, and tourism. In recent years, many environmental problems have emerged, such as the frequent(almost yearly) occurre... Daya Bay, a semi-enclosed bay in the South China Sea, is well known for its aquaculture, agriculture, and tourism. In recent years, many environmental problems have emerged, such as the frequent(almost yearly) occurrence of harmful algal blooms and red tides. Therefore,investigations of submarine groundwater discharge(SGD) and associated nutrient inputs to this bay have important theoretical and practical significance to the protection of the ecological system. Such a study was conducted using short-lived radium isotopes ^(223)Ra and ^(224)Ra. The estimated SGD fluxes were 2.89 × 10~7 m^3/d and 3.05 × 10~7 m^3/d based on ^(223)Ra and ^(224)Ra, respectively. The average SGD flux was about 35 times greater than that of all the local rivers. The SGD-associated dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphorus(DIP)fluxes ranged from 1.95 × 10~6 to 2.06 × 10~6 mol/d and from 5.72 × 10~4 to 6.04 × 10~4 mol/d, respectively. The average ratio of DIN to DIP fluxes in SGD was 34, much higher than that in local rivers(about 6.46), and about twice as large as the Redfield ratio(16). Our results indicate that SGD is a significant source of nutrients to the bay and may cause frequent occurrence of harmful algal blooms. This study provides baseline data for evaluating potential environmental effects due to urbanization and economic growth in this region. 展开更多
关键词 Submarine groundwater discharge(SGD) radium ISOTOPES radium mass balance model SGD-associated nutrient FLUXES DAYA Bay
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Evaluation of shallow groundwater discharge fluxes and nutrient fluxes in the west of Qinghai Lake using radium isotopes 被引量:1
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作者 KONG Fancui SHA Zhanjiang +1 位作者 SU Weigang YU Chenguang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期145-148,共4页
We collected 14 samples and 9 samples for surface water in Quan bay and the north bay of Qinglai Lake respectively,as well as 11 samples for groundwater and 3 samples for river water.First the water samples were filte... We collected 14 samples and 9 samples for surface water in Quan bay and the north bay of Qinglai Lake respectively,as well as 11 samples for groundwater and 3 samples for river water.First the water samples were filtered through a 展开更多
关键词 Qinghai Lake radium isotopes shallow groundwater SGD
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Radium-traced nutrient outwelling from the Subei Shoal to the Yellow Sea:Fluxes and environmental implication 被引量:1
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作者 Jian’an Liu Dongyan Liu Jinzhou Du 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第6期12-21,共10页
The Subei Shoal is the largest sandy ridge in the southern Yellow Sea and is important source for nutrient loading to the sea.Here,the nutrient fluxes in the Subei Shoal associated with eddy diffusion and submarine gr... The Subei Shoal is the largest sandy ridge in the southern Yellow Sea and is important source for nutrient loading to the sea.Here,the nutrient fluxes in the Subei Shoal associated with eddy diffusion and submarine groundwater discharge(SGD)were assessed to understand their impacts on the nutrient budget in the Yellow Sea.Based on the analysis of 223 Ra and 224 Ra in the field observation,the offshore eddy diffusivity mixing coefficient and SGD were estimated to be 2.3×10^(8)cm^(2)/s and 2.6×10^(9)m^(3)/d(16 cm/d),respectively,in the Subei Shoal.Combined the significant offshore decreasing gradients of nutrient in seawater of the Subei Shoal,the spatially integrated nutrient outwelling fluxes to the Yellow Sea were 262-1465μmol/(m^(2)·d)for DIN,5.2-21μmol/(m^(2)·d)for DIP and711-913μmol/(m^(2)·d)for DSi.Compared to the riverine input,atmospheric deposition and mariculture,nutrient outwelling from the Subei Shoal might play an important role in nutrient budget of the Yellow Sea.These nutrient fluxes could provide 4.1%-23%N and 1.3%-5.3%P requirements for the primary productivity,and the deviated DIN/DIP ratios have the potential to affect the growth of phytoplankton in the marine ecosystem of the Yellow Sea. 展开更多
关键词 nutrient outwelling eddy diffusion submarine groundwater discharge radium isotopes Subei Shoal Yellow Sea
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Submarine groundwater discharge and associated nutrient fluxes in the Greater Bay Area, China revealed by radium and stable isotopes 被引量:1
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作者 Qianqian Wang Xuejing Wang +4 位作者 Kai Xiao Yan Zhang Manhua Luo Chunmiao Zheng Hailong Li 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第5期397-410,共14页
The estuary-bay system is a common and complex coastal environment.However,quantifying submarine groundwater discharge(SGD)and associated nutrient fluxes in the complex coastal environment is challenging due to more d... The estuary-bay system is a common and complex coastal environment.However,quantifying submarine groundwater discharge(SGD)and associated nutrient fluxes in the complex coastal environment is challenging due to more dynamic and complicated riverine discharge,ocean processes and human activities.In this study,SGD and SFGD(submarine fresh groundwater discharge)fluxes were evaluated by combining stable and radium isotopes in the Guangdong-Hong Kong-Macao Greater Bay Area(GBA),a typical estuary-bay system.We first built a spatially distributed radium mass balance model to quantify SGD fluxes in coastal areas of GBA integrating the Pearl River Estuary(PRE),bays and shelf.We then used the stable water isotope(d2 H and d18O)end-member mixing model to distinguish submarine fresh groundwater discharge(SFGD)from SGD.Based on the 228Ra mass balance,the estimated SGD fluxes in the PRE,adjacent bay,and shelf areas were(6.14±2.74)×10^(8) m^(3) d^(-1),(3.00±1.11)×10^(7) m^(3) d^(-1),and(5.00±5.64)×10^(8) m^(3) d^(-1),respectively.Results showed that the largest area-averaged SGD was in the PRE,followed by that in the adjacent shelf and the bay.These differences may be mainly influenced by ocean forces,urbanization and benthic topographies controlling the variability of groundwater pathways.Further,the three end-member mixing model of ^(228)Ra and salinity was developed to confirm the validity of the estimated SGD using the Ra mass balance model.In the two models,groundwater endmember and water apparent age estimation were the main sources of uncertainty in SGD.The estimated SFGD flux was(1.39±0.76)108 m^(3) d^(-1),which accounted for approximately 12%of the total SGD.Combining stable and radium isotopes was a useful method to estimate groundwater discharge.Moreover,the estimated SGD associated dissolved inorganic nitrogen(DIN)flux was one order of magnitude higher than other DIN sources.SGD was considered to be a significant contributor to the DIN loading to the GBA.The findings of this study are expected to provide valuable information on coastal groundwater management and environmental protection of the GBA and similar coastal areas elsewhere. 展开更多
关键词 radium isotopes Stable isotopes Submarine fresh groundwater discharge NUTRIENTS Coastal aquifers Pearl River estuary
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Radium and Uranium Concentrations Measurements in Vegetables Samples of Iraq 被引量:1
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作者 Abdalsattar Kareem Hashim Laith Ahmed Najam 《Detection》 2015年第4期21-28,共8页
In the present study twenty-two vegetable samples were collected from Iraqi market. Sealed can technique using CR-39 plastic track detector strippable has been used in order to measure radium and uranium concentration... In the present study twenty-two vegetable samples were collected from Iraqi market. Sealed can technique using CR-39 plastic track detector strippable has been used in order to measure radium and uranium concentrations. Etching was done with 6.25 N NaOH and optical microscope was used with the purpose of counting of alpha particle tracks. The values of effective radium content are found to range from 0.074 Bq/ kg to 0.566 Bq/ kg with the mean value of 0.317 Bq/kg. The values of uranium concentrations are found to range from 0.081 ppm to 0.615 ppm with the mean value of 0.345 ppm. Positive correlation has been observed between radium concentration and uranium concentrations in vegetable samples. Measurements of radium and uranium concentrations in vegetables are important from the health protection point of view, so simple and reliable analytical methods must be available. 展开更多
关键词 radium URANIUM Can Technique CR-39 Detectors VEGETABLES IRAQI MARKETS
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Radium-223 in metastatic castration resistant prostate cancer 被引量:1
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作者 Winston Vuong Oliver Sartor Sumanta K Pal 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第3期348-353,共6页
In 2004, docetaxel was approved for the treatment of metastatic castration-resistant prostate cancer (mCRPC). For the next several years, there was a lull in drug approvals. However, from 2010 onwards, 5 additional ... In 2004, docetaxel was approved for the treatment of metastatic castration-resistant prostate cancer (mCRPC). For the next several years, there was a lull in drug approvals. However, from 2010 onwards, 5 additional therapies have been approved on the basis of showing a survival benefit in phase III studies. These agents include sipuleuceI-T, cabazitaxel, abiraterone, enzalutamide and (most recently) radium-223. Amongst radiopharmaceuticals currently used for advanced prostate cancer (e.g. samarium-153 and strontium-89), radium-223 possesses several unique properties. As an alpha-emitting compound, the agent produces a high-energy output over a short range, facilitating selective destruction of tissue within the bone in the region of osteoblastic lesions while sparing surrounding normal tissue. The current review will outline biological rationale for radium-223 and also provide an overview of preclinical and clinical development of the agent. Rational sequencing of radium-223 and combinations, in the increasingly complex landscape of mCRPC will be discussed, along with factors influencing clinical implementation. 展开更多
关键词 alpharadin bone metastases metastatic castration-resistant prostate cancer RADIOPHARMACEUTICALS radium-223 Xofigo
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Radium isotopes assess water mixing processes and its application in the Zhujiang River estuary
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作者 郭肖伊 许博超 +6 位作者 于志刚 李秀芹 南海明 简慧敏 江雪艳 刁少波 高茂生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第5期1108-1116,共9页
Radium (Ra) isotopes are useful for tracing water mass transport and examining estuarine hydrological dynamics. In this study, several hydrological parameters, nutrients, ehlorophyll-a (ehl-a), suspended particula... Radium (Ra) isotopes are useful for tracing water mass transport and examining estuarine hydrological dynamics. In this study, several hydrological parameters, nutrients, ehlorophyll-a (ehl-a), suspended particulate matter (SPM) and Ra isotopes (223Ra, 224Ra and 226Ra) of surface waters of the Zhujiang (Pearl) River estuary (ZRE) were measured. This was done for both winter (December) and summer (July) seasons, to quantitatively understand the seasonal characteristics of river plume flow rate and trajectories, as well as the ecological response. The results show that Ra concentrations in summer were higher than in winter, especially Z24Ra (about 2-5 times higher). The spatial distribution of three Ra isotopes and relative Ra water ages indicated that river water mainly flushed out of ZRE through the western side in winter, where the water transport was about 5 days faster than in the eastern zone. In summer, diluted river water expended to the east side, resulting in fairly similar water ages for both sides of the river mouth. Although nutrients were higher during the summer season, lower chl-a concentrations indicated that reduced primary production might be caused by high SPM (low light penetration). The results obtained from this study will provide knowledge needed for effectively developing and managing the ZRE. 展开更多
关键词 Zhujiang River estuary radium isotopes water ages NUTRIENTS
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Radium Isotopes in an Oil-Field Produced Lake near Baku, Azerbaijan
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作者 Famil Yusif Humbatov Bahruz Allahverdi Suleymanov +2 位作者 Majid Mirza Ahmedov Majid Mirza Ahmedov Valeh Saleh Balayev 《Journal of Environmental Protection》 2016年第9期1149-1156,共9页
An assessment of radiologically enhanced residual materials generated during oil and gas production in near Baku, Azerbaijan, was conducted. Distribution of the <sup>228</sup>Ra/<sup>226</sup>R... An assessment of radiologically enhanced residual materials generated during oil and gas production in near Baku, Azerbaijan, was conducted. Distribution of the <sup>228</sup>Ra/<sup>226</sup>Ra Activity Ratio (AR) with depth in a sediment core from radium lake was examined. The dashed line represented ingrowth assuming that <sup>228</sup>Ra was below equilibrium with <sup>232</sup>Th in the young sediments near the top and reached equilibrium at a depth around 10 cm. In this study the radium isotopic data are used to provide estimates of the age of formation of the radiobarite contaminant and age of oil field lake. The results indicate that, the upper two layers in the core (up to 4 cm) contain fallout <sup>137</sup>Cs so at least these layers are no older than about 40 yrs. Formation waters that are sent to disposal ponds may consist of accumulated heavy hydrocarbons, paraffin, inorganic solids, and heavy emulsions. We report here results of chemical and radiochemical measurements from formation waters separated from oil pumped from approximately 700 m below ground near Baku, Azerbaijan. Our results also include data from a formation water storage pond (“radium lake”) where the waters are temporarily stored after oil is separated and then eventually disposed of by pumping into the Caspian Sea. We also analyzed the associated sediment for radiochemical components. Our study was intended to investigate how radium fractionated between the pond water and sediments. 展开更多
关键词 Oil Industry Formation Water SEDIMENTS radium Isotopes NORM AZERBAIJAN
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Zou Hengyu, China's No.1 Maker of Radium Emanated Leather Products
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《China's Foreign Trade》 2001年第9期12-13,共2页
关键词 AS China’s No.1 Maker of radium Emanated Leather Products Zou Hengyu
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M-Audio Radium 49全功能MIDI键盘
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作者 小柯 《乐器》 2004年第12期88-89,共2页
Radium49(中译名镭)是一种全新形式的MIDI控制键盘,是为迎合当今电脑音乐制作的最新发展潮流而设计的产品,除MIDI琴键外,它还可以同时对你音乐软件上的16个参数进行实时调控,并提供了内置的USB接口可与电脑直接相连。
关键词 radium49 MIDI键盘 技术指标 音乐软件 USB接口 功能
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Determination of Radium-226 in Rock Samples by Liquid Scintillation Counter
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作者 W. M. Abdellah 《Open Journal of Applied Sciences》 2019年第4期270-284,共15页
The present work examines the validity of using barium as a carrier for radium-226 determination and optimizes the amount added during the radiochemical separation from rock samples. The activity concentration of Ra-2... The present work examines the validity of using barium as a carrier for radium-226 determination and optimizes the amount added during the radiochemical separation from rock samples. The activity concentration of Ra-226 is determined in rock samples by liquid scintillation spectrometer via its short-lived daughters after the radiochemical separation. The activity of Ra-226 was calculated based on the counts measured in a window set for Po-214 peak. The activity measured by Liquid Scintillation Counter, LSC using Pulse Shape Analysis, PSA. Ba-133 was used for chemical yield. The applied method was tested using a Certified Reference Material, CRM ore number-Dl-1a which shows a good agreement with the certified values. The applied method for measuring Ra-226 has been adapted to be used in rocks such as monazite. The average activity for Ra-226 in rock samples collected from the commercial grade Egyptian monazite was 13.85 ± 2.05 Bq/g with a detection limit 9.58 mBq/g. The optimum conditions have been established during the present work such as precision, cost and time preparation which makes the method useful for radio chemists and the decision makers. 展开更多
关键词 LIQUID Scintillation COUNTER SPECTROMETRY ROCK MONAZITE radium-226
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Analysis of Radium Isotopes in Surface Waters nearby a Phosphate Mining with NORM at Santa Quiteria,Brazil
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作者 Wagner de S.Pereira Alphonse Kelecom Juliana R.de S.Pereira 《Journal of Environmental Protection》 2014年第3期193-199,共7页
The radium isotopes 226Ra and 228Ra were analyzed in surface water at six points in the neighborhood of a mine of phosphate, associated with uranium, in the region of Santa Quitéria, state of Ceará, Brazil. ... The radium isotopes 226Ra and 228Ra were analyzed in surface water at six points in the neighborhood of a mine of phosphate, associated with uranium, in the region of Santa Quitéria, state of Ceará, Brazil. Water samples were collected during twenty months, filtered and the concentrations of activity determined in the soluble and particulate phases. The results were analyzed using the Principal Component Analysis (PCA) for ordination of environmental data, and also by ANOVA, Tukey and Z tests to compare sets of data considering the radionuclides, the two analyzed phases and the six collecting points. The PCA identified four groups that included all collecting points, using aggregation features such as radionuclide and analyzed phase. The first group is composed by the samples of 226Ra in the soluble phase;the second group by samples of 226Ra in the particulate phase;the third one by 228Ra in the soluble phase, and finally, the fourth group by 228Ra in the particulate phase. This last group has two discrepant points (01 and 06). Statistical analysis identified differences between the concentrations of activity of radionuclides (228Ra higher than 226Ra) and in analyzed phases (soluble phase higher than the particulate one) but showed no differences between sampled points. 展开更多
关键词 RADIOECOLOGY Environmental Radioprotection NORM Mining radium Isotopes PCA
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