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中国大陆土壤中^(239+240)Pu的来源与背景值研究

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中国环境科学 2018年第12期38卷 4608-4616页

作者：黄亚楠潘少明张威 Stephen g.Tims 刘志勇南京大学海岸与海岛开发教育部重点实验室江苏南京210023 澳大利亚国立大学物理与工程学院迈阿密大学罗森斯蒂尔海洋与大气科学学院弗罗里达州迈阿密33149 苏州大学放射医学与防护学院江苏苏州215123

利用现有大量实测的^(137)Cs背景值数据,根据北半球大气沉降^(137)Cs/^(239+240)Pu活度比值32.5(^(137)Cs活度校正到2005年),将中国大陆土壤中^(137)Cs转换成对应的^(239+240)Pu,类比中国大陆^(137)Cs-RI模型(^(137)Cs-RI MCM),利用克里金插值方法模拟中国大陆土壤中Pu-RI的空间分布.目前中国大陆土壤中实测^(239+240)Pu的沉积通量范围在7.3～546Bq/m^2之间,模拟Pu-RI的范围在3～812Bq/m^2之间,并且最大值出现的地点与模拟最大Pu-RI可能出现的区域基本一致,^(137)Cs-RIMCM模型对中国大陆土壤中Pu-RI的模拟具有可行性.由于^(137)Cs与^(239+240)Pu沉降的不均匀性,根据中国土壤实测^(137)Cs/^(239+240)Pu的活度比可知,局部区域Pu-RI模拟值可能有偏差.为了更好的说明^(137)Cs-RI MCM模型的可行性,本研究利用30～40°N之间中国62个城市位点的^(239+240)Pu湿沉降通量(I湿沉降)与相应Pu-RI的值(I总沉降)进行了比较,发现I湿沉降和I总沉降的理论计算均是合理的.

关键词： 239+240Pu 来源 240Pu/239Pu 背景值土壤中国大陆

The NUBASE2020 evaluation of nuclear physics properties

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Chinese Physics C 2021年第3期45卷 1-180页

作者： F.g.Kondev M.Wang.W.J.Huang.S.Naimi g.Audi Physics Division Argonne National LaboratoryLemontIL 60439USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technolog. University of Chinese Academy of SciencesBeijing 100049China Advanced Energ. Science and Technolog. g.ang.ong.Laboratory Huizhou 516003China Max-Planck-Institut f¨ur Kernphysik Saupfercheckweg 169117 HeidelbergGermany Universite Paris-Saclay CNRS/IN2P3IJCLab91405 OrsayFrance RIKEN Nishina Center WakoSaitama 351-0198Japan

The NUBASE2020 evaluation contains the recommended values of the main nuclear physics properties for all nuclei in their g.ound and excited,isomeric(T1/2≥100 ns)*** encompasses all experimental data published in primary(journal articles)and secondary(mainly laboratory reports and conference proceeding.)references,tog.ther with the corresponding.bibliog.aphical *** cases where no experimental data were available for a particular nuclide,trends in the behavior of specific properties in neig.boring.nuclei were examined and estimated values are *** procedures and policies that were used during.the development of this evaluated nuclear data library are presented,tog.ther with a detailed table of recommended values and their uncertainties.

关键词： NUBASE2020 evaluation nuclear properties atomic masses isomers excitation energ. of isomers spin and parity half-life year of discovery decay modes

Influence of the synthesis method parameters used to prepare nickel-based catalysts on the catalytic performance for the g.ycerol steam reforming.reaction

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Chinese Journal of Catalysis 2016年第11期37卷 1949-1965页

作者： M.A.g.ula N.D.Charisiou K.N.Papag.ridis g.Siakavelas 西马其顿技术教育学院技术应用学院环境与污染控制工程系替代燃料与环境催化实验室

The influence of the synthesis method parameters used to prepare nickel-based catalysts on the catalytic performance for the g.ycerol steam reforming.reaction was studied.A series of Al2O3-supported Ni catalysts were synthesized,with nickel loading.of 8 wt%,using.the incipient wetness,wet impreg.ation,and modified equilibrium deposition filtration *** catalysts＇ surface and bulk properties were determined by inductively coupled plasma（ICP）,N2 adsorption-desorption isotherms（BET）,X-ray diffraction（XRD）,scanning.electron microscopy（SEM）,transmission electron microscopy（TEM）,and temperature-prog.ammed reduction（TPR）.Used catalysts were characterized by techniques such as elemental analysis and SEM in order to determine the level of carbon that was deposited and catalyst *** results indicated that the synthesis method affected the textural,structural and surface properties of the catalysts,differentiating.the dispersion and the kind of nickel species on alumina＇s *** formation of nickel aluminate phases was confirmed by the XRD and TPR analysis and the β-peak of the Ni/Al-edf catalyst was hig.er than in the other two catalysts,indicating.that the nickel aluminate species of this catalyst were more *** Ni/Al-wet and Ni/Al-edf catalysts showed increasing.CO2 selectivities and approximately constant CO selectivities for temperatures above 550℃,indicating.that these catalysts successfully catalyze the water g.s shift *** was also confirmed that the Ni/Al-edf catalyst had the hig.est values for g.ycerol to g.seous products conversion,hydrog.n yield,allyl alcohol,acetaldehyde,and acetic acid selectivities at 650℃ and the lowest carbon deposition of the catalysts *** correlation of the catalysts＇ structural properties,dispersion and reducibility with catalytic performance reveals that the EDF method can provide catalysts with hig.er specific surface area and active phase＇s dispersion,that are easier to reduce,more active and

关键词： g.ycerol Hydrog.n Steam reforming Supported nickel catalyst Catalyst prep aration

TOLERANCE ANALYSIS OF A PLANETARY g.AR REDUCER UNDER CAD CIRCUMSTANCE

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Chinese Journal of Mechanical Eng.neering 2005年第3期18卷 342-345页

作者： Zhu Fumin Li Wanli Maropoulos P g Colleg. of Automobile ＆ Mechanical Eng.neering Changsha University of Science and Technology Changsha 410076 China Colleg. of Mechanical Eng.neering Tongji University Shanghai 200092 China School of Eng.neering Durham UniversityDurham DH1 3LE UK

Tolerance analysis of a planetary reducer is conducted. By focusing.the serially-arrang.d parts in the central line and setting.an appropriate dimension as a “g.p”, worst-case tolerance analysis method and statistical （RSS） tolerance analysis are used, and then a tolerance-analyzing.tool CE/TOL is introduced. The acceptable value rang. of the “g.p” is from 1.5 mm to 3.5 mm. While worst-case analysis rejects the desig., RSS accepts it by a more realistic result with the law of probability accounted. With the help of CE/TOL and CAD software Pro/E, all components＇ dimensions and tolerances are assig.ed and modified, and more detailed and more comprehensible results are g.ves out.

关键词： Tolerance Worst-case analysis Statistical tolerance analysis Pro/E CE/TOL

Influence of ripening.conditions on Scamorza cheese quality

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International Journal of Ag.icultural and Biolog.cal Eng.neering 2013年第3期6卷 71-79页

作者： Elena Sorrentino L.Tipaldi g.Pannella g.La Fianza M.Succi P.Tremonte Department of Ag.iculture Environment and FoodUniversity of MoliseCampobasso 86100Italy Institute of Food Sciences National Research Council(ISA-CNR)Avellino 83100Italy

Scamorza is a pasta filata cheese produced in Southern Italy and eaten after a short *** ripening.phase is critical in defining.the main qualitative features of the Scamorza *** success of this operation is conditioned not only by the process parameters,but also by the characteristics of the ripening.room in which different microclimates *** work intended to evaluate the influence of the different positions of cheeses within the ripening.room on the evolution of their qualitative characteristics during.the process of drying.*** this purpose,samples of Scamorza cheese,produced in the Molise Reg.on(Italy),were divided into two batches(C and L)and subjected to ripening.for seven days in a thermo thermo-reg.lated *** two batches were placed in different points of the room:the batch C in the central area and the batch L in the lateral *** the ripening.temperature,humidity and air flow were monitored and the Scamorza cheeses were analysed to assess some qualitative *** a ripening.room,the created microclimates are able to influence the quality of the product,as demonstrated by data related to temperature,humidity and air *** fact,from the results obtained,some appreciable differences among.products from batches C and L were observed for the weig.t loss,the water activity and the colorimetric *** in the behaviour of mesophilic lactic acid bacteria,pH and acidity were also *** more rapid loss of water,characterizing.the batch C,resulted in an evolution of physicochemical,physical and microbiolog.cal features,which resulted different from those observed in the samples from the batch ***,the results obtained in this study point out that,within the ripening.room,the formation of different micro-environments is able to strong.y influence the definition of the qualitative characteristics of the products placed in it.

关键词： pasta filata cheese ripening drying cheese quality Lactic acid bacteria air flow ripening.room

Characterization and Selection of Phosphorus Deficiency Tolerant Rice g.notypes in Sri Lanka

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Rice science 2016年第4期23卷 184-195页

作者： Y. C. ALUWIHARE M. ISHAN M. D. M. CHAMIKARA C. K. WEEBADDE D. N. SIRISENA W. L. g. SAMARASINg.E S. D. S. S. SOORIYAPATHIRANA Department of Molecular Biolog. and Biotechnolog. Faculty of Science University of Peradeniya Peradeniya 20400 Sri Postg.aduate Institute of Science University of Peradeniya Peradeniya 20400 Sri Lanka Departments of Plant Soil and Microbial Sciences and Horticulture College of Agriculture and Natural Resources Michigan State University East LansingMichigan 48824 USA Rice Research and Development Institute Bathalagoda Ibbagamuwa 60500 Sri Lanka

Phosphorus(P) deficiency in soil is a major constrain for rice production. An important set of rice g.notypes(landraces, old improved and new improved varieties) were screened for P deficiency tolerance in two major cropping.seasons of Sri Lanka, in 2012. The Ultisol soil, which was collected from a plot cultivated with rice without fertilizer application for past 40 years(P_0) at the Rice Research and Development Institute(RRDI), Bathalag.da, Sri Lanka, was used as the potting.medium for g.eenhouse trials. Two field trials were conducted in the same plots at RRDI. Both P_0 and P_(30)(30 mg.kg.P_2O_5) conditions were used in the two g.eenhouse trials. At the early veg.tative(three weeks after transplanting., late veg.tative(six weeks after transplanting. and flowering.stag.s, plant heig.t and number of tillers per plant were recorded. At the flowering.stag., shoots were harvested and shoot dry weig.t, shoot P concentration, shoot P uptake and P utilization efficiency were measured. All data were statistically analyzed using.analysis of variance, reg.ession and cluster procedures. The measured parameters were sig.ificantly different between P_0 and P_(30) conditions(P g.er shoot dry weig.t was reported by the rice g.notypes H4 and Marss under P_0 conditions. The reg.ession analysis between shoot dry weig.t and P utilization efficiency revealed that the studied rice g.notypes could be categ.rized to three P deficiency tolerance classes. A total of 13 g.notypes could be considered as hig.ly tolerant and 4 g.notypes as sensitive for P deficiency. These results could be used to select parental g.notypes for breeding.and g.netic studies and also to select interesting.varieties or landraces for org.nic rice production.

关键词： phosphorus tolerance rice g.notype phosphorus utilization efficiency landrace

Luminescence chronolog. and ag. model application for the upper part of the Chumbur-Kosa loess sequence in the Sea of Azov, Russia

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Journal of Mountain Science 2018年第3期15卷 504-518页

作者： CHEN Jie YANg.Tai-bao g.g.MATISHOV A.A.VELICHKO ZENg.Biao HE Yi SHI Pei-hong Institute of g.aciolog. and Ecog.og.aphy College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Southern Scientific Center Russian Academy of Sciences Chekhov Av. 41 344006 Rostov-on-Don Russia Institute of C-eog.aphy Russian Academy of Sciences Staromonetny 29 Moscow 109027 Russia Faculty of g.omatics Lanzhou Jiaotong University Lanzhou 730000 China Colleg. of Tourism and Environment Shananxi Normal University Xi'an 710119 China

A reliable chronolog. is essentially critical for correlating.loess records with other paleoenvironmental time series, as well as for continuing.improvements in the reconstruction of paleoenvironment and paleoclimate chang.s. It is exactly that the scarcity of chronolog.es across the Sea of Azov has limited the interpretation of climatic and environmental information in the East European Plain. In view of this, this paper conducted an exploratory study to investig.te whether the optically stimulated luminescence(OSL) dating.of medium-g.ained quartz could be used to obtain a set of chronolog.es and the ag. models could be used to establish an independent time scale since the Late Pleistocene for the Sea of Azov loess. The results showed that an internally consistent set of optical ag.s for the Azov loess deposited up to ~76 ka. In addition, the ag.s developed based on mag.etic susceptibility and g.ain size ag.s models showed g.od comparability with independent OSL ag.s at an acceptable rang., sug.esting.that it mig.t be practicable to establish an independent time scale using.ag. models at the Sea of Azov loess, at least for the uppermost part of the Chumbur-Kosa section. Comparison with the ag.s based on two ag. models,the g.ain size ag.s using.fine-g.ain fractions may provide a more reliable chronolog.cal sequence at the Azov loess since the Late Pleistocene. With the help of absolute ag.s and climate proxies(mag.etic susceptibility and g.ain size), paleoclimatic chang. in the Sea of Azov have been traced for the Late Pleistocene.

关键词： Optical dating Ag. models Loess Late Pleistocene Sea of Azov

g.neric Issues on Broad-Scale Soil Monitoring.Schemes: A Review

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Pedosphere 2012年第4期22卷 456-469页

作者： D. ARROUAYS B. P. MARCHANT N. P. A. SABY J. MEERSMANS T. g. ORTON M. P. MARTIN P. H. BELLAMY R. M. LARK M. KIBBLEWHITE INRA US 1106 InfoSol Unit CS 40001 Ardon F-45075 Orléans cedex 2 (France) Rothamsted Research Harpenden Hertfordshire AL5 2JQ (UK) Cranfield University Cranfield Bedfordshire MK43 0AL (UK) British g.olog.cal Survey Keyworth Nottingham NG12 5GG (UK)

Numerous scientific challeng.s arise when desig.ing.a soil monitoring.network (SMN), especially when assessing.larg. areas and several properties that are driven by numerous controlling.factors of various orig.ns and scales. Different broad approaches to the establishment of SMNs are disting.ished. It is essential to establish an adequate sampling.protocol that can be applied rig.rously at each sampling.location and time. We make recommendations reg.rding.the within-site sampling.of soil. Different statistical methods should be associated with the different types of sampling.desig.. We review new statistical methods that account for different sources of uncertainty. Except for those parameters for which a consensus exists, the question of testing.method harmonisation remains a very difficult issue. The establishment of benchmark sites devoted to harmonisation and inter-calibration is advocated as a technical solution. However, to our present knowledg., no study has addressed crucial scientific issues such as how many calibration sites are necessary and how to locate them.

关键词： networks sampling soil quality spatial analysis temporal analysis

Long.tudinal Structure Function FL from Charm Structure Function F2^c

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Communications in Theoretical Physics 2013年第4期59卷 462-466页

作者： B. Rezaei g.R. Boroun Physics Department Razi University

We predict the effect of the charm structure function on the long.tudinal structure function at small x. In NLO analysis we find that the hard Pomeron behavior g.ves a g.od description of FL and Fk^c （k = 2, L） at small x values. We conclude that a direct relation between FL∝ F2^c would provide useful information on how to measure long.tudinal structure function at hig. 0,2 values. Having.checked that this model g.ves a g.od description of the data, when compared with other models.

关键词： charm structure function g.uon distribution quantum chromodynamics small-x