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高放废液中微量Am的放化分析
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作者 陈耀中 谈炳美 林漳基 《原子能科学技术》 EI CAS CSCD 北大核心 1992年第3期80-85,共6页
为了对后处理厂储存的高放废液(1AW)进一步处理处置,需要对废液组分进行分析。Am是重要的α放射体之一,因此,要求对废液中Am含量进行测定。高放废液中,除了Am之外,还有U、Np、Pu、裂片元素以及大量的无机盐,Am的含量极低,必须先进行Am... 为了对后处理厂储存的高放废液(1AW)进一步处理处置,需要对废液组分进行分析。Am是重要的α放射体之一,因此,要求对废液中Am含量进行测定。高放废液中,除了Am之外,还有U、Np、Pu、裂片元素以及大量的无机盐,Am的含量极低,必须先进行Am的放化分离。我们曾相继报道过有关Am的纯化工作,本文着重介绍Am的分离纯化程序。 展开更多
关键词 高效废液 放化分析
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肿瘤受体显像剂^(99)Tc^m-octreotide的放化纯度分析 被引量:2
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作者 王叙馥 左书耀 +3 位作者 邵文博 王国明 孙建文 张勤 《同位素》 CAS 2003年第1期26-29,共4页
采用高压液相色谱分析(HPLC)和双层析结合银染色两种方法,对新型肿瘤受体显像剂^(99)Tc^m-oc-treotide的放化纯度进行分析。结果表明,双层析法结合银染色可以准确、有效地分离^(99)Tc^m-octreotide及其它放射性组分,可以较精确地计算出... 采用高压液相色谱分析(HPLC)和双层析结合银染色两种方法,对新型肿瘤受体显像剂^(99)Tc^m-oc-treotide的放化纯度进行分析。结果表明,双层析法结合银染色可以准确、有效地分离^(99)Tc^m-octreotide及其它放射性组分,可以较精确地计算出显像剂的放化纯度。为Octreotide及其它多肽类显像剂的放化纯度测定提供了一种简捷、准确的新手段。 展开更多
关键词 肿瘤受体显像剂 纯度分析 高压液相色谱分析 银染色 双层析 奥曲肽 肿瘤定位
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用Ge(Li)γ-谱仪和组分离相结合的方法对两个岩石标准参考物质DZ∑-1,DZ∑-2的多元素中子活化分析 被引量:2
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作者 陈保观 袁玲 方朝萌 《岩矿测试》 CAS 1983年第3期219-221,I0007,共4页
本工作参照Johansen等人分离Fe,Co的优点,以阴离子交换和反相色层法有效地除去Cr,Fe,Co,Sc放射性核素的干扰、用国际标样验证了方法的可靠性。仪器及试剂γ—射线谱仪:仪器中子活化分析,测量系统是由一个70cm^(3)同轴Ge(Li)探测器,对^(6... 本工作参照Johansen等人分离Fe,Co的优点,以阴离子交换和反相色层法有效地除去Cr,Fe,Co,Sc放射性核素的干扰、用国际标样验证了方法的可靠性。仪器及试剂γ—射线谱仪:仪器中子活化分析,测量系统是由一个70cm^(3)同轴Ge(Li)探测器,对^(60)Co1332KeV峰的分辨率为3.5KeV,峰康比为20∶1和一台Laben—4096多道分析器组成,放化中子活化分析,测量系统是由一个130cm^(3),CANBERRA同轴Ge(Li)探测器,对Co 1332KeV峰的分辨率为1.9KeV和一台SCORPIO—3000多道计算机组成,对Co 1332KeV峰的峰康比为48∶1,相对探测效率为30%,两台谱仪系统刻度每道为0.5KeV。 展开更多
关键词 中子活分析 仪器中子活分析 标准参考物质 反相色层 阴离子交换 多道分析 射性核素 测量系统
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大面积低水平α放射性能谱源的制备和样品的测定方法 被引量:8
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作者 李树棠 杨大亭 +1 位作者 刘玉莲 夏益华 《核化学与放射化学》 CAS CSCD 北大核心 1989年第3期149-155,共7页
本文叙述了1400cm^2的α放射性能谱源制备工艺流程和样品中α核素的测定方法。通过样品处理,用超声波粉碎,在真空干燥箱中制成大面积源。湿颗粒度≤1μm,不均匀性<9.5%。牢固性满足要求,源分辨率为70keV(对70μg/cm^2,^(241)Am),制... 本文叙述了1400cm^2的α放射性能谱源制备工艺流程和样品中α核素的测定方法。通过样品处理,用超声波粉碎,在真空干燥箱中制成大面积源。湿颗粒度≤1μm,不均匀性<9.5%。牢固性满足要求,源分辨率为70keV(对70μg/cm^2,^(241)Am),制源流程半机械化。8小时可作一个样品。 样品在大面积α屏栅电离室中测量,绘成谱图,计算α核素的比活度,全程回收率为99.1±4.6%,方法下限为6.7×10^(-4)Bq/g(固体)。还测定了7种样品中α核素的谱图和比活度,并用IAEA标准参考物质进行比对。 展开更多
关键词 α核素 射源 放化分析
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堆芯混凝土样品中^(63)Ni的分析测量
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作者 王萍 但贵萍 +2 位作者 谭昭怡 苏容波 杜良 《核化学与放射化学》 CAS CSCD 北大核心 2015年第6期457-462,共6页
为建立堆芯混凝土材料中^(63)Ni活度测量的方法,进行了溶样方法的确定、淋洗曲线的绘制、液闪测量效率的确定、回收率实验、去污实验及空白实验等方面的研究工作。混凝土样品磨至粒径小于0.074mm,用混合酸(V(HNO_3)∶V(HClO_4)∶V(HF)=3... 为建立堆芯混凝土材料中^(63)Ni活度测量的方法,进行了溶样方法的确定、淋洗曲线的绘制、液闪测量效率的确定、回收率实验、去污实验及空白实验等方面的研究工作。混凝土样品磨至粒径小于0.074mm,用混合酸(V(HNO_3)∶V(HClO_4)∶V(HF)=3∶2∶1)进行溶解,再通过阴离子交换分离、氢氧化物沉淀及萃取和反萃等样品纯化程序去除杂质离子后,用液体闪烁能谱仪测量其中^(63)Ni的活度。该方法的化学回收率为73.05%,放化回收率为71.99%,通过空白实验得出计数的标准偏差为0.200/s,相对标准偏差为12.8%(n=12),方法检出限为3.596Bq/g。该方法可应用于堆内混凝土材料及非堆材料中63 Ni的常规监测及应急监测。 展开更多
关键词 混凝土 放化分析 63Ni 液闪测量
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食品中^(241)Am标准分析程序
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作者 刘庆芬 刘书田 +2 位作者 潘竞舜 杨大亭 诸洪达 《中国辐射卫生》 北大核心 2005年第4期244-246,共3页
目的介绍《食品中241Am测定》标准分析程序实验验证依据。方法根据标准分析流程进行全流程回收率、方法检测下限和去污试验;结果全程回收率76.26±4.1%,最小可探测下限为3.4×10-5Bq/g灰,方法对Po的去污系数(DF)大于103,对U、Th... 目的介绍《食品中241Am测定》标准分析程序实验验证依据。方法根据标准分析流程进行全流程回收率、方法检测下限和去污试验;结果全程回收率76.26±4.1%,最小可探测下限为3.4×10-5Bq/g灰,方法对Po的去污系数(DF)大于103,对U、Th、Pu的DF均大于102,对237Np的DF大于60。结论全程回收率高且稳定,方法最小可探测下限可满足对食品中241Am限制量监测的要求,用243Am标准溶液和241Am标准参考物质全程验证实验结果表明符合很好。 展开更多
关键词 食品检验 放化分析 电沉积 α能谱
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天津市气溶胶中210Po的分析研究
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作者 刘大江 《绿色环保建材》 2021年第1期37-38,共2页
目的:调查研究2019年天津市空气中210Po的活度浓度水平,为天津市辐射环境监测和辐射应急监测提供数据支持;方法:参照《水中钋-210的分析方法》(HJ 813—2016),通过以209Po为示踪剂、气溶胶强酸消解、银片自沉积地放化分析方法制备样品源... 目的:调查研究2019年天津市空气中210Po的活度浓度水平,为天津市辐射环境监测和辐射应急监测提供数据支持;方法:参照《水中钋-210的分析方法》(HJ 813—2016),通过以209Po为示踪剂、气溶胶强酸消解、银片自沉积地放化分析方法制备样品源,并采用α能谱仪测量,开展对环境气溶胶中210Po的定性定量分析;[结果]2019年天津市气溶胶中210Po的活度浓度范围在0.27mBq/m^(3)~0.88mBq/m^(3)之间,平均值0.49mBq/m^(3);结论:天津市环境气溶胶中的210Po活度浓度水平整体表现为冬季较高,夏季较低,可能受到天津市空气中总悬浮颗粒物浓度变化的影响。 展开更多
关键词 气溶胶 210Po 放化分析 活度浓度
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Estimate of China's energy carbon emissions peak and analysis on electric power carbon emissions 被引量:7
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作者 WANG Zhi-Xuan ZHANG Jing-Jie +2 位作者 PAN Li YANG Fan SHI Li-Na 《Advances in Climate Change Research》 SCIE 2014年第4期181-188,共8页
China's energy carbon emissions are projected to peak in 2030 with approximately 110% of its 2020 level under the following conditions: 1) China's gross primary energy consumption is 5 Gtce in 2020 and 6 Gtce in 2... China's energy carbon emissions are projected to peak in 2030 with approximately 110% of its 2020 level under the following conditions: 1) China's gross primary energy consumption is 5 Gtce in 2020 and 6 Gtce in 2030; 2) coal's share of the energy consumption is 61% in 2020 and 55% in 2030; 3) non-fossil energy's share increases from 15% in 2020 to 20% in 2030; 4) through 2030, China's GDP grows at an average annual rate of 6%; 5) the annual energy consumption elasticity coefficient is 0.30 in average; and 6) the annual growth rate of energy consumption steadily reduces to within 1%. China's electricity generating capacity would be 1,990 GW, with 8,600 TW h of power generation output in 2020. Of that output 66% would be from coal, 5% from gas, and 29% from non-fossil energy. By 2030, electricity generating capacity would reach 3,170 GW with 11,900 TW h of power generation output. Of that output, 56% would be from coal, 6% from gas, and 37% from non-fossil energy. From 2020 to 2030, CO2 emissions from electric power would relatively fall by 0.2 Gt due to lower coal consumption, and rela- tively fall by nearly 0.3 Gt with the installation of more coal-fired cogeneration units. During 2020--2030, the portion of carbon emissions from electric power in China's energy consumption is projected to increase by 3.4 percentage points. Although the carbon emissions from electric power would keep increasing to 118% of the 2020 level in 2030, the electric power industry would continue to play a decisive role in achieving the goal of increase in non-fossil energy use. This study proposes countermeasures and recommendations to control carbon emissions peak, including energy system optimization, green-coal-fired electricity generation, and demand side management. 展开更多
关键词 Energy consumption Growth rate Carbon emissions peak Electric power development
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Pancreatic cancer–Adjuvant therapy
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作者 Asma Sultana John Neoptolemos Paula Ghaneh 《The Chinese-German Journal of Clinical Oncology》 CAS 2007年第2期170-175,共6页
Pancreatic cancer ranks tenth in terms of newly diagnosed cases, but just 10%–15% of these patients can undergo resection. Survival after curative surgery is dismal, as recurrences occur either locally or in the live... Pancreatic cancer ranks tenth in terms of newly diagnosed cases, but just 10%–15% of these patients can undergo resection. Survival after curative surgery is dismal, as recurrences occur either locally or in the liver. Adjuvant treatment with either chemotherapy or chemoradiation (with or without maintenance chemotherapy) has been employed, to improve the poor prognosis. Justification for the use of chemoradiation, with follow on chemotherapy, is based on the results of an underpowered 1987 GITSG study, which closed prematurely and compared intervention to observation. There has been no survival advantage demonstrated in the one randomized controlled trial that examined chemoradiation compared to chemotherapy. There is a clear cut survival advantage however with chemotherapy compared to observation, based on the results from two large randomized controlled trials, and supported by an individual patient data meta-analysis. The standard of care for adjuvant therapy based on level I evidence (from the ESPAC-1 trial) is post operative chemotherapy using 5-Fluorouracil with folinic acid providing a best estimate of 29% five years survival. 展开更多
关键词 pancreas cancer CHEMOTHERAPY CHEMORADIATION adjuvant treatment META-ANALYSIS
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Empirically Analysis of the CO_2 Emissions Embodied in Exports of China 被引量:1
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作者 Zhu Qirong 《Chinese Journal of Population,Resources and Environment》 2011年第3期86-96,共11页
In this paper,using the input-output model,the author first calculated the CO 2 emissions embodied in exports of China in 2002 and 2007.Then,the author empirically analyzed problems existing in the composition of expo... In this paper,using the input-output model,the author first calculated the CO 2 emissions embodied in exports of China in 2002 and 2007.Then,the author empirically analyzed problems existing in the composition of exported products and analyzed its possible reasons.The research results of this paper are as follows:Since China's entry into WTO,the CO 2 emissions embodied in exports of China have been increasing rapidly;the value of exported products of high-carbon emissions industries accounts for a relatively higher proportion to China's total exports value because China's carbon intensive products have a certain competitive advantage.Additionally,this paper has put forward relevant suggestions based on these results. 展开更多
关键词 EXPORTS CO2 emissions carbon intensive prod-ucts inputoutput model
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Emission Characteristics of Volatile Organic Compounds from Automobile Coating Industry in Chongqing City
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作者 Zhou Zhi'en Fang Weikai +2 位作者 Luo Qian Wang Xiaochen Wu Liping 《Journal of Environmental Science and Engineering(B)》 2017年第11期543-552,共10页
To fully analyze emission characteristics of VOCs (Volatile Organic Compounds) from automobile coating industry in Chongqing city, related enterprises in the city were investigated in detail. The results show that t... To fully analyze emission characteristics of VOCs (Volatile Organic Compounds) from automobile coating industry in Chongqing city, related enterprises in the city were investigated in detail. The results show that the emission of VOCs from the automobile industry in Chongqing city was approximately 20,000 t in 2012, and the contribution rate of automobile coating was 83%. Most VOCs discharged from automobile coating industry were mainly from the use of coatings, diluents, curing agents and other materials containing VOCs. During the process of automobile coating, VOCs were mainly produced during the processes of spraying and drying. Besides, VOCs are partly produced during the processes of mixing paint, gluing, waxing and repairing. The major ingredients of VOCs discharged during the process of automobile coating were methylbenzene, dimethylbenzene, trimethylbenzene, cumene, ethyl acetate, butyl alcohol, n-butyl alcohol, isobutyl alcohol, formaldehyde, butanone, acetone, cyclohexanone and methyl ethyl ketone. Besides, the ingredients of naphtha and aromatic hydrocarbon in VOCs need to be determined. The maximum OFP (Ozone Formation Potential) of the above pollutants by the typical enterprises was 900-1,300 mg/m^3. The production of SOA (Secondary Organic Aerosol) was 3,636-11,073 t/a, which didn’t include the contribution of aldehydes, ketones, ethers and esters to SOA. This research could provide scientific reference for the establishment of emission standard, control technology and management methods of VOCs from automobile coating industry that accord with economic and social development in Chongqing city. 展开更多
关键词 Automobile coating VOCs environmental impact OZONE SOA.
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Analysis of Potential for HFC-23 Emission Reduction in China's Fluorine Chemical Industry
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作者 LIN Hui CUI Yong-Li YANG Li-Rong 《Advances in Climate Change Research》 SCIE 2013年第4期260-266,共7页
China is one of the major producers of chlorodifluoromethane(HCFC-22)in the world.A large amount of fluoroform(HFC-23)is emitted during the production of HCFC-22.Emission factors of HFC-23 were calculated in accordanc... China is one of the major producers of chlorodifluoromethane(HCFC-22)in the world.A large amount of fluoroform(HFC-23)is emitted during the production of HCFC-22.Emission factors of HFC-23 were calculated in accordance with the monitoring reports of eleven HFC-23 clean development mechanism(CDM)projects in China and the HFC-23emissions in 2000–2010 as well as that in 2011–2020 were estimated and projected,respectively.It is expected that,by the end of 2020,emissions of HFC-23 in China will be as much as 230 Mt CO2-eq.If HCFC-22 producers voluntarily reduced HFC-23 emissions,it would contribute 3.2%–3.6%to the national CO2emission reduction target for 2020. 展开更多
关键词 greenhouse gas HFC-23 potential for emission reduction
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A Review of Energy Efficiency in Data Processing Centers
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作者 C. Redondo A. Fern/mdez 《Journal of Energy and Power Engineering》 2011年第4期361-372,共12页
This article explores, through a case study, measures of energy efficiency in data processing centers. An analysis of this case demonstrates how the design criteria could improve the rate of consumption in IT centers,... This article explores, through a case study, measures of energy efficiency in data processing centers. An analysis of this case demonstrates how the design criteria could improve the rate of consumption in IT centers, which is currently the second most contaminating industry on the planet, and is the responsible for 2% of CO2 emissions, surpassed only by the aeronautical industry. The present and future situation of IT center energy consumption and associated environmental effects is analyzed, and also looks at how state-of-the-art technology, correctly implemented, could ensure significant rationalization of data processing center energy consumption. The article will examine optimization techniques, specific problems and case studies. 展开更多
关键词 Energy management data processing centers energy efficiency.
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Analysis of the Clean Development Mechanism Considering the Environmental Co-benefits of Reducing Air Pollutants in China
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作者 Jianguo Liang Akinobu Murata +1 位作者 Koji Tokimatsu Yohji Uchiyama 《Journal of Energy and Power Engineering》 2014年第2期244-256,共13页
An electricity generation planning model of the six major Chinese power grids was developed based on the General Algebraic Modeling System to evaluate and analyze the CDM (clean development mechanism), including con... An electricity generation planning model of the six major Chinese power grids was developed based on the General Algebraic Modeling System to evaluate and analyze the CDM (clean development mechanism), including consideration of the environmental co-benefits of reductions in air pollutants (SO~, NO~ and particulate matter) achieved by advanced electricity generation technologies incorporating CCS (carbon capture and storage). An objective function was developed that included revenue from sales of electric power, total system cost, the cost of CO2 transport and storage, and emissions reduction co-benefits for SOx, NO~, and particulate matter. The objective function was minimized using an optimization model. We also developed a method for evaluating and analyzing the potential for transferring advanced power generation technologies into the Chinese power system through the CDM. We found that: (1) thermal power generation is predominant in the Chinese electricity system and will remain so for a long time; (2) advanced thermal plants are being installed as a result of the CDM, which contribute to decreasing emissions of CO2 and other air pollutants; and (3) CCS projects have significant potential to reduce substantial and sustained CO2 emissions from the Chinese power and industrial sectors. 展开更多
关键词 Generation planning model carbon capture and storage CO-BENEFITS advanced power generation CDM activities.
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Role of adjuvant(chemo)radiotherapy for resected extrahepatic cholangiocarcinoma:a meta-analysis 被引量:2
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作者 Xin-qi SHI Jing-yu ZHANG +2 位作者 Hua TIAN Ling-na TANG Ai-lin LI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2020年第7期549-559,共11页
Background:Adjuvant(chemo)radiotherapy(A(C)RT)may be an important supplement to surgery for extrahepatic cholangiocarcinoma(EHCC).However,whether all patients would achieve benefits from A(C)RT and which adjuvant regi... Background:Adjuvant(chemo)radiotherapy(A(C)RT)may be an important supplement to surgery for extrahepatic cholangiocarcinoma(EHCC).However,whether all patients would achieve benefits from A(C)RT and which adjuvant regimen,adjuvant radiotherapy(ART)or adjuvant chemoradiotherapy(ACRT),would be preferred,are still undetermined.The low incidence of EHCC makes it difficult to carry out randomized controlled trials(RCTs);therefore,almost all clinical studies on radiotherapy are retrospective.We have conducted a meta-analysis of these retrospective studies.Methods:We conducted a meta-analysis of current retrospective studies using PubMed,Embase,and ClinicalTrials databases.All studies published in English that were related to A(C)RT and which analyzed overall survival(OS),disease-free survival(DFS),or locoregional recurrence-free survival(LRFS)were included.Estimated hazard ratios(HRs)were calculated for OS,DFS,and LRFS.Results:Data from eight studies including 685 patients were included.Our analysis showed that A(C)RT significantly improved OS(HR 0.69,95%confidence interval(CI)0.48–0.97,P=0.03),DFS(HR 0.60,95%CI 0.47–0.76,P<0.0001),and LRFS(HR 0.27,95%CI 0.17–0.41,P<0.00001)of EHCC overall.In subgroups,patients with microscopically positive resection margin(R1)could achieve a benefit from A(C)RT(HR 0.44,95%CI 0.27–0.72,P=0.001).No statistically OS difference was observed in negative resection margin(R0)subgroup(HR 0.98,95%CI 0.30–3.19,P=0.98).Significant OS benefit was found in patients who received concurrent ACRT(HR 0.40,95%CI 0.26–0.62,P<0.0001),while the result of ART without chemotherapy showed no significant benefit(HR 1.14,95%CI 0.29–4.50,P=0.85).In the distal cholangiocarcinoma subgroup,no significant difference was seen when ACRT and ART were included(HR 0.61,95%CI 0.14–2.72,P=0.52),but a significant difference was seen ewOshSpe,enDc iaFanlSla,yl yianzn iddn igsL ttRahlF ep Sca iotinne cEnutHrsr.C eCnt pAaCtieRnTt so,nelys p(eHcRi a0 ll.y2 i9 n,t9 h5 o%s eC Iw i0 t.h13 R–10 r.e6 s4 e,cPti=o0 n.0 m0 a2 r).g iCnso.n AclCusRioT nms:aAy(bCe)RsTu pmeraiyo ri tmop rAoRvTe . 展开更多
关键词 Adjuvant(chemo)radiotherapy Extrahepatic cholangiocarcinoma META-ANALYSIS Disease-free survival Overall survival
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Performance analysis for power generating system by using matrix method 被引量:2
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作者 Kanji OSHIMA Yohji UCHIYAMA 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第7期1689-1696,共8页
We verified that the matrix method, a process analysis method used mainly for life cycle inventory analysis, has several advantages in the analysis of power systems, which have recently become more complex to enhance ... We verified that the matrix method, a process analysis method used mainly for life cycle inventory analysis, has several advantages in the analysis of power systems, which have recently become more complex to enhance efficiency and to reduce C02 emissions. While designing a conceptual thermodynamic model of a complex power system, the matrix method provides a definite procedure and facilitates calculations, even if there is a recttrsive loop between the upstream and downstream processes. Similarly, in the case of partial modification to the constructed model, the matrix method can potentially reduce the time and effort required to calculate the thermodynamic balances, even if the constructed model is designed by others. In this study, we obtained mass flow and energy balances of example model power systems by the matrix method from the common thermodynamic conditions including temperatures and pressures which are set on the basis of an existing industrial steam power system. While analyzing the environmental impact of complex multiproduct power systems, such as carbon emissions, the matrix method can be used to easily derive the environmental impact of each final product. We could verify the efficacy of the matrix method in accurately deriving that of an example model power system. 展开更多
关键词 power system matrix method EFFICIENCY environmental impact hybrid power generation conceptual design
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